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Sample records for cells pathologic mechanism

  1. Pathologic pancreatic endocrine cell hyperplasia

    Institute of Scientific and Technical Information of China (English)

    Debra Ouyang; Deepti Dhall; Run Yu

    2011-01-01

    Pathologic hyperplasia of various pancreatic endocrine cells is rare but has been long known. β cell hyperplasia contributes to persistent hyperinsulinemic hypoglycemia of infancy, which is commonly caused by mutations in the islet ATP-sensitive potassium channel, and to noninsulinoma pancreatogenous hypoglycemia in adults,which may or may not be associated with bariatric surgery.α cell hyperplasia may cause glucagonoma syndrome or induce pancreatic neuroendocrine tumors. An inactivating mutation of the glucagon receptor causes α cell hyperplasia and asymptomatic hyperglucagonemia.Pancreatic polypeptide cell hyperplasia has been described without a clearly-characterized clinical syndrome and hyperplasia of other endocrine cells inside the pancreas has not been reported to our knowledge.Based on morphological evidence, the main pathogenetic mechanism for pancreatic endocrine cell hyperplasia is increased endocrine cell neogenesis from exocrine ductal epithelium. Pancreatic endocrine cell hyperplasia should be considered in the diagnosis and management of hypoglycemia, elevated islet hormone levels,and pancreatic neuroendocrine tumors. Further studies of pathologic pancreatic endocrine cell hyperplasia will likely yield insights into the pathogenesis and treatment of diabetes and pancreatic neuroendocrine tumors.

  2. [Vascular Calcification - Pathological Mechanism and Clinical Application - . Role of vascular smooth muscle cells in vascular calcification].

    Science.gov (United States)

    Kurabayashi, Masahiko

    2015-05-01

    Vascular calcification is commonly seen with aging, chronic kidney disese (CKD), diabetes, and atherosclerosis, and is closely associated with cardiovascular morbidity and mortality. Vascular calcification has long been regarded as the final stage of degeneration and necrosis of arterial wall and a passive, unregulated process. However, it is now known to be an active and tightly regulated process involved with phenotypic transition of vascular smooth muscle cells (VSMC) that resembles bone mineralization. Briefly, calcium deposits of atherosclerotic plaque consist of hydroxyapatite and may appear identical to fully formed lamellar bone. By using a genetic fate mapping strategy, VSMC of the vascular media give rise to the majority of the osteochondrogenic precursor- and chondrocyte-like cells observed in the calcified arterial media of MGP (- / -) mice. Osteogenic differentiation of VSMC is characterized by the expression of bone-related molecules including bone morphogenetic protein (BMP) -2, Msx2 and osteopontin, which are produced by osteoblasts and chondrocytes. Our recent findings are that (i) Runx2 and Notch1 induce osteogenic differentiation, and (ii) advanced glycation end-product (AGE) /receptor for AGE (RAGE) and palmitic acid promote osteogenic differentiation of VSMC. To understand of the molecular mechanisms of vascular calcification is now under intensive research area.

  3. Myoepithelial cells in pathology

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    N Balachander

    2015-01-01

    Full Text Available Myoepithelial cells are a normal constituent of the salivary acini and ducts and are found between the epithelial cells and the basement membrane. Microscopically myoepithelial cells are thin and spindle-shaped and ultrastructurally they possess a number of Cytoplasmic processes that extend between and over the acinar and ductal-lining cells, and they show features of both smooth muscle and epithelium. They play a vital role during expulsion of saliva and regulates the electrolytic exchange. They also perform as tumor suppressors and are considered to play a very important role in differentiation of various salivary gland tumors and help in the diagnosis of tumors. Neoplastic myoepithelial cells in both benign and malignant tumors can take numerous forms including epithelioid, plasmacytoid, spindle and clear cell variant, and this variability largely accounts for difficulties in histopathological diagnosis.

  4. Synaptic Contacts Enhance Cell-to-Cell Tau Pathology Propagation

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    Sara Calafate

    2015-05-01

    Full Text Available Accumulation of insoluble Tau protein aggregates and stereotypical propagation of Tau pathology through the brain are common hallmarks of tauopathies, including Alzheimer’s disease (AD. Propagation of Tau pathology appears to occur along connected neurons, but whether synaptic contacts between neurons are facilitating propagation has not been demonstrated. Using quantitative in vitro models, we demonstrate that, in parallel to non-synaptic mechanisms, synapses, but not merely the close distance between the cells, enhance the propagation of Tau pathology between acceptor hippocampal neurons and Tau donor cells. Similarly, in an artificial neuronal network using microfluidic devices, synapses and synaptic activity are promoting neuronal Tau pathology propagation in parallel to the non-synaptic mechanisms. Our work indicates that the physical presence of synaptic contacts between neurons facilitate Tau pathology propagation. These findings can have implications for synaptic repair therapies, which may turn out to have adverse effects by promoting propagation of Tau pathology.

  5. Synaptic Contacts Enhance Cell-to-Cell Tau Pathology Propagation.

    Science.gov (United States)

    Calafate, Sara; Buist, Arjan; Miskiewicz, Katarzyna; Vijayan, Vinoy; Daneels, Guy; de Strooper, Bart; de Wit, Joris; Verstreken, Patrik; Moechars, Diederik

    2015-05-26

    Accumulation of insoluble Tau protein aggregates and stereotypical propagation of Tau pathology through the brain are common hallmarks of tauopathies, including Alzheimer's disease (AD). Propagation of Tau pathology appears to occur along connected neurons, but whether synaptic contacts between neurons are facilitating propagation has not been demonstrated. Using quantitative in vitro models, we demonstrate that, in parallel to non-synaptic mechanisms, synapses, but not merely the close distance between the cells, enhance the propagation of Tau pathology between acceptor hippocampal neurons and Tau donor cells. Similarly, in an artificial neuronal network using microfluidic devices, synapses and synaptic activity are promoting neuronal Tau pathology propagation in parallel to the non-synaptic mechanisms. Our work indicates that the physical presence of synaptic contacts between neurons facilitate Tau pathology propagation. These findings can have implications for synaptic repair therapies, which may turn out to have adverse effects by promoting propagation of Tau pathology.

  6. Power loss mechanisms in pathological tracheas.

    Science.gov (United States)

    Bates, A J; Comerford, A; Cetto, R; Schroter, R C; Tolley, N S; Doorly, D J

    2016-07-26

    The effort required to inhale a breath of air is a critically important measure in assessing airway function. Although the contribution of the trachea to the total flow resistance of the airways is generally modest, pathological alterations in tracheal geometry can have a significant negative effect. This study investigates the mechanisms of flow energy loss in a healthy trachea and in four geometries affected by retrosternal goitre which can cause significant distortions of tracheal geometry including constriction and deviation with abnormal curvature. By separating out the component of energy loss related to the wall shear (frictional loss), striking differences are found between the patterns of energy dissipation in the normal and pathological tracheas. Furthermore the ratio of frictional to total loss is dramatically reduced in the pathological geometries. PMID:26686396

  7. The "Shaken Baby" syndrome: pathology and mechanisms.

    Science.gov (United States)

    Squier, Waney

    2011-11-01

    The "Shaken Baby" syndrome (SBS) is the subject of intense controversy; the diagnosis has in the past depended on the triad of subdural haemorrhage (SDH), retinal haemorrhage and encephalopathy. While there is no doubt that infants do suffer abusive injury at the hands of their carers and that impact can cause catastrophic intracranial damage, research has repeatedly undermined the hypothesis that shaking per se can cause this triad. The term non-accidental head injury has therefore been widely adopted. This review will focus on the pathology and mechanisms of the three physiologically associated findings which constitute the "triad" and are seen in infants suffering from a wide range of non-traumatic as well as traumatic conditions. "Sub" dural bleeding in fact originates within the deep layers of the dura. The potential sources of SDH include: the bridging veins, small vessels within the dura itself, a granulating haemorrhagic membrane and ruptured intracranial aneurysm. Most neuropathologists do not routinely examine eyes, but the significance of this second arm of the triad in the diagnosis of Shaken Baby syndrome is such that it merits consideration in the context of this review. While retinal haemorrhage can be seen clinically, dural and subarachnoid optic nerve sheath haemorrhage is usually seen exclusively by the pathologist and only rarely described by the neuroradiologist. The term encephalopathy is used loosely in the context of SBS. It may encompass anything from vomiting, irritability, feeding difficulties or floppiness to seizures, apnoea and fulminant brain swelling. The spectrum of brain pathology associated with retinal and subdural bleeding from a variety of causes is described. The most important cerebral pathology is swelling and hypoxic-ischaemic injury. Mechanical shearing injury is rare and contusions, the hallmark of adult traumatic brain damage, are vanishingly rare in infants under 1 year of age. Clefts and haemorrhages in the immediate

  8. Immunohistochemistry of Programmed Cell Death in Archival Human Pathology Specimens

    OpenAIRE

    Takami Matsuyama; Yoshito Eizuru; Takuro Kanekura; Yoshifumi Kawano; Shuji Izumo; Xinshan Jia; Katsuyuki Aozasa; Taku Nagai; Jia Wang; Kazuhisa Hasui

    2012-01-01

    Immunohistochemistry (IHC) for detecting key signal molecules involved in programmed cell death (PCD) in archival human pathology specimens is fairly well established. Detection of cleaved caspase-3 in lymphocytes in rheumatoid arthritis (RA) and gastric surface foveolar glandular epithelia but not in synoviocytes in RA, gastric fundic glandular epithelia, or nasal NK/T-cell lymphoma (NKTCL) cells suggests anti-apoptotic mechanisms in cell differentiation and in oncogenesis such as the induct...

  9. Neuronal trafficking: basic mechanisms and ALS pathology

    NARCIS (Netherlands)

    Kuijpers, M.

    2014-01-01

    A cell is divided into different compartments and organelles, which enables the cell to create specialized environments for specific functions. To perform these functions, organelles need a unique composition of proteins and lipids. By actively controlling the trafficking of proteins and membrane li

  10. Synaptic Contacts Enhance Cell-to-Cell Tau Pathology Propagation

    OpenAIRE

    Sara Calafate; Arjan Buist; Katarzyna Miskiewicz; Vinoy Vijayan; Guy Daneels; Bart de Strooper; Joris de Wit; Patrik Verstreken; Diederik Moechars

    2015-01-01

    Accumulation of insoluble Tau protein aggregates and stereotypical propagation of Tau pathology through the brain are common hallmarks of tauopathies, including Alzheimer’s disease (AD). Propagation of Tau pathology appears to occur along connected neurons, but whether synaptic contacts between neurons are facilitating propagation has not been demonstrated. Using quantitative in vitro models, we demonstrate that, in parallel to non-synaptic mechanisms, synapses, but not merely the close dista...

  11. Immunohistochemistry of Programmed Cell Death in Archival Human Pathology Specimens

    Directory of Open Access Journals (Sweden)

    Takami Matsuyama

    2012-05-01

    Full Text Available Immunohistochemistry (IHC for detecting key signal molecules involved in programmed cell death (PCD in archival human pathology specimens is fairly well established. Detection of cleaved caspase-3 in lymphocytes in rheumatoid arthritis (RA and gastric surface foveolar glandular epithelia but not in synoviocytes in RA, gastric fundic glandular epithelia, or nasal NK/T-cell lymphoma (NKTCL cells suggests anti-apoptotic mechanisms in cell differentiation and in oncogenesis such as the induction of survivin. Enzymatically pretreated and ultra-super sensitive detection of beclin-1 in synoviocytes in RA and gastric fundic glandular epithelia suggests enhanced autophagy. The deposition of beclin-1 in fibrinoid necrosis in RA and expression of beclin-1 in detached gastric fundic glandular cells suggest that enhanced autophagy undergoes autophagic cell death (ACD. NKTCL exhibited enhanced autophagy through LC3 labeling and showed densely LC3 labeled cell-debris in regions of peculiar necrosis without deposition of beclin-1, indicating massive ACD in NKTCL and the alternative pathway enhancing autophagy following autophagic vesicle nucleation. Autophagy progression was monitored by labeling aggregated mitochondria and cathepsin D. The cell-debris in massive ACD in NKTCL were positive for 8-hydroxydeoxyguanosine, suggesting DNA oxidation occurred in ACD. Immunohistochemical autophagy and PCD analysis in archival human pathology specimens may offer new insights into autophagy in humans.

  12. The mechanism of pathological changes of intraventricular hemorrhage in dogs

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    Dai Jiong

    2009-12-01

    Full Text Available Background : Intraventricular hemorrhage (IVH is an independent risk factor for both morbidity and mortality in patients with intracerebral hemorrhage and subarchnoid hemorrhage. The pathophysiological mechanisms by which blood within the ventricles causes brain damage are still poorly understood. Settings and Design : We developed a canine (dog model with long-term survival. Aims : To study the mechanisms of pathological changes associated with IVH. Materials and Methods : The neurological status, cranial computed tomographic findings, and the pathological changes were studied in the dogs with IVH and also in the control dogs, intraventiricular saline injection. Results : In all the dogs in the control group there were no abnormalities in all the three parameters studied. The dogs in the IVH group developed neurological deficits after the blood injection. There was linear relationship between the ventricular volume and blood clot volume in the first week. After the first week, there was progressive enlargement of the ventricular volume, while the clots continued to shrink. There was complete lysis of the clots within 4 weeks. Pathological studies showed distruction of the ependymal lining of the ventricular system, subependymal gliosis and ischemia of the neurons in the subependymal areas, prominently around the aqueduct. Conclusion : Ventricular dilation was the prominent feature following intraventricular injection of the blood. The other pathological features included disruption of ependymal lining, subependymal gliosis, and ischemic necrosis of neurons in the periventricular tissue of the third ventricle, aqueduct, and the fourth ventricle. These pathological may have some role in the ventricular dilatation following IVH.

  13. The mechanism of pathological changes of intraventricular hemorrhage in dogs

    OpenAIRE

    Dai Jiong; Li Shanquan; Li Xiaoxiong; Xiong Wenhao; Qiu Yongming

    2009-01-01

    Background : Intraventricular hemorrhage (IVH) is an independent risk factor for both morbidity and mortality in patients with intracerebral hemorrhage and subarchnoid hemorrhage. The pathophysiological mechanisms by which blood within the ventricles causes brain damage are still poorly understood. Settings and Design : We developed a canine (dog) model with long-term survival. Aims : To study the mechanisms of pathological changes associated with IVH. Materials and Methods : The neurologi...

  14. A classification of the mechanisms producing pathological tissue changes.

    Science.gov (United States)

    Grippo, John O; Oh, Daniel S

    2013-05-01

    The objectives are to present a classification of mechanisms which can produce pathological changes in body tissues and fluids, as well as to clarify and define the term biocorrosion, which has had a singular use in engineering. Considering the emerging field of biomedical engineering, it is essential to use precise definitions in the lexicons of engineering, bioengineering and related sciences such as medicine, dentistry and veterinary medicine. The mechanisms of stress, friction and biocorrosion and their pathological effects on tissues are described. Biocorrosion refers to the chemical, biochemical and electrochemical changes by degradation or induced growth of living body tissues and fluids. Various agents which can affect living tissues causing biocorrosion are enumerated which support the necessity and justify the use of this encompassing and more precise definition of biocorrosion. A distinction is made between the mechanisms of corrosion and biocorrosion.

  15. Omnis cellula e cellula revisited: cell biology as the foundation of pathology.

    Science.gov (United States)

    Wright, Nicholas A; Poulsom, Richard

    2012-01-01

    This 2012 Annual Review Issue of The Journal of Pathology argues strongly that cell biology, in its many disciplines, underpins the foundation of our understanding of the mechanisms of disease-the holy grail of pathology. Our increasing knowledge of the human genome will not be enough to attain this goal without parallel developments in our comprehension of the results, at the cellular level, of these genetic changes. In the end, it is cell biology and cell biologists who will deliver this mission.

  16. Cell Biology and Pathology of Podocytes

    Science.gov (United States)

    Greka, Anna; Mundel, Peter

    2013-01-01

    As an integral member of the filtration barrier in the kidney glomerulus, the podocyte is in a unique geographical position: It is exposed to chemical signals from the urinary space (Bowman’s capsule), it receives and transmits chemical and mechanical signals to/from the glomerular basement membrane upon which it elaborates, and it receives chemical and mechanical signals from the vascular space with which it also communicates. As with every cell, the ability of the podocyte to receive signals from the surrounding environment and to translate them to the intracellular milieu is dependent largely on molecules residing on the cell membrane. These molecules are the first-line soldiers in the ongoing battle to sense the environment, to respond to friendly signals, and to defend against injurious foes. In this review, we take a membrane biologist’s view of the podocyte, examining the many membrane receptors, channels, and other signaling molecules that have been implicated in podocyte biology. Although we attempt to be comprehensive, our goal is not to capture every membrane-mediated pathway but rather to emphasize that this approach may be fruitful in understanding the podocyte and its unique properties. PMID:22054238

  17. Stem cell applications for pathologies of the urinary bladder

    Institute of Scientific and Technical Information of China (English)

    2015-01-01

    New stem cell based therapies are undergoing intenseresearch and are widely investigated in clinical fieldsincluding the urinary system. The urinary bladderperforms critical complex functions that rely on its highlycoordinated anatomical composition and multiplex ofregulatory mechanisms. Bladder pathologies resulting insevere dysfunction are common clinical encounter andoften cause significant impairment of patient's quality oflife. Current surgical and medical interventions to correcturinary dysfunction or to replace an absent or defectivebladder are sub-optimal and are associated with notablecomplications. As a result, stem cell based therapiesfor the urinary bladder are hoped to offer new venuesthat could make up for limitations of existing therapies.In this article, we review research efforts that describethe use of different types of stem cells in bladderreconstruction, urinary incontinence and retentiondisorders. In particular, stress urinary incontinence hasbeen a popular target for stem cell based therapiesin reported clinical trials. Furthermore, we discuss therelevance of the cancer stem cell hypothesis to thedevelopment of bladder cancer. A key subject thatshould not be overlooked is the safety and quality ofstem cell based therapies introduced to human subjectseither in a research or a clinical context.

  18. MECHANISM OF PATHOLOGICAL CHANGES OF INTRAVENTRICULAR HEMORRHAGE IN DOGS

    Institute of Scientific and Technical Information of China (English)

    戴炯; 李善泉; 李骁雄; 徐斌斌; 熊文浩; 王勇; 张晓华; 沈加林

    2004-01-01

    Objective To probe the mechanism of pathological changes of intraventricular hemorrhage (IVH). Methods The evaluation of neurological status, serial CT scans and pathological examination were ap plied on the canine model of lVH. The ventricular volume and blood clot volume were measured based on the CT images. Results The normal adult canine ventricle tend to be slitlike. After injection, the ventricle was obviously dilated by the blood clot. The linear regression of ventricular volume against blood clot volume was significant in the first week. From then on, however, while the clots continued to shrink, the ventricular volume showed progressive enlargement. The clots were lysed completely within 3 to 4 weeks. The linear regression of the degree of ventricular dilatation against the first clot volume was also significant. In the pathological examination, we found the ependymal lining of ventricular system was destroyed and neurons in the subependymal areas developed acidophil necrosis, which was prominent around Sylvian aqueduct. Conclusion Hemorrhagic ventricular dilatation(HVD) is a prominent feature of IVH and also is a strong indicator for poor prognosis. lschemic changes of periventricular neurons in some important structures may be the most direct cause for poor outcome of IVH. It may be induced by periventricular vascular structures compressed by HVD, increased intracranial pressure ,cerebral vasospasm and others.

  19. Pathological Consequence of Misguided Dendritic Cell Differentiation in Histiocytic Diseases

    OpenAIRE

    Berres, Marie-Luise; Allen, Carl E.; Merad, Miriam

    2013-01-01

    Histiocytic disorders represent a group of complex pathologies characterized by the accumulation of histiocytes, an old term for tissue-resident macrophages and dendritic cells. Langerhans cell histiocytosis is the most frequent of histiocytosis in humans and has been thought to arise from the abnormal accumulation of epidermal dendritic cells called Langerhans cells. In this chapter, we discuss the origin and differentiation of Langerhans cells and dendritic cells and present accumulated evi...

  20. Pathological modifications of plant stem cell destiny

    Science.gov (United States)

    In higher plants, the shoot apex contains undifferentiated stem cells that give rise to various tissues and organs. The fate of these stem cells determines the pattern of plant growth as well as reproduction; and such fate is genetically preprogrammed. We found that a bacterial infection can derai...

  1. Radiation-Induced Heart Disease: Pathologic Abnormalities and Putative Mechanisms

    Directory of Open Access Journals (Sweden)

    Neil K Taunk

    2015-02-01

    Full Text Available Breast cancer is a common diagnosis in women. Breast radiation has become a critical in managing patients who receive breast conserving surgery, or have certain high-risk features after mastectomy. Most patients have an excellent prognosis, therefore understanding the late effects of radiation to the chest is important. Radiation induced heart disease (RIHD comprises a spectrum of cardiac pathology including myocardial fibrosis and cardiomyopathy, coronary artery disease, valvular disease, pericardial disease, and arrhythmias. Tissue fibrosis is a common mediator in RIHD. Multiple pathways converge with both acute and chronic cellular, molecular, and genetic changes to result in fibrosis. In this article, we review the pathophysiology of cardiac disease related to radiation therapy to the chest. Our understanding of these mechanisms has improved substantially, but much work remains to further refine radiation delivery techniques and develop therapeutics to battle late effects of radiation.

  2. [Molecular pathology of plasma cell neoplasms].

    Science.gov (United States)

    Fend, F

    2010-10-01

    Plasma cell myeloma (PCM) and related immunosecretory disorders are a group of B-cell proliferations with a wide clinical and prognostic spectrum, characterized by the production of monoclonal immunoglobulin by immortalized plasma cells. Recent years have seen an explosion in knowledge on the genetic basis and biology of these diseases, followed by improved clinical risk stratification and the introduction of novel therapeutic concepts, such as treatment with proteasome inhibitors or immunomodulatory substances. PCM is a common malignancy, accounting for approximately 10% of all hematological neoplasms. There is good evidence to support a multistep transformation process in plasma cell neoplasms, which corresponds to clinically discernible disease stages. Monoclonal gammopathy of unknown significance is a common asymptomatic precursor lesion for PCM which carries an approximately 1% annual risk for progression. Terminal disease stages are characterized by increasing genetic complexity and independence from bone marrow stromal cells and show a rapidly increasing tumour load with severe clinical symptoms. Modern diagnostics of plasma cell neoplasms require inclusion of clinical, morphological, immunophenotypical and cytogenetic features to allow for individual risk assessment and therapy planning. PMID:20852863

  3. Mechanics rules cell biology

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    Wang James HC

    2010-07-01

    Full Text Available Abstract Cells in the musculoskeletal system are subjected to various mechanical forces in vivo. Years of research have shown that these mechanical forces, including tension and compression, greatly influence various cellular functions such as gene expression, cell proliferation and differentiation, and secretion of matrix proteins. Cells also use mechanotransduction mechanisms to convert mechanical signals into a cascade of cellular and molecular events. This mini-review provides an overview of cell mechanobiology to highlight the notion that mechanics, mainly in the form of mechanical forces, dictates cell behaviors in terms of both cellular mechanobiological responses and mechanotransduction.

  4. Physiological Function and Pathological Mechanisms of Liver Sinusoidal Endothelial Cell%肝窦内皮细胞生理功能及病理过程的分子机制

    Institute of Scientific and Technical Information of China (English)

    劳远翔; 贺福初; 姜颖

    2012-01-01

    Liver sinusoidal endothelial cell ( LSEC ) is a main population of liver non-parenchymal cells. LSEC has a number of important functions, such as filtration, phagocytosis, antigen presentation, immune tolerance. When liver is invaded by a variety of pathogens, LSECs lose fenestrations and form an underlying basement membrane, which are the characteristics of continuous endothelial cells, this process was called capillarization. LSEC capillarization is a complex life activity induced by several factors, and exists in the early stage of diverse liver diseases, thus attracted much attention on such a study. Herein, the research progress in the studies on the physiological function of LSEC and the molecular mechanisms of sinusoidal endothelial cell pathology were introduced in detail. First, the function of LSEC was summarized. Second, in addition to studies on the mechanisms of sinusoidal capillarization, the roles of sinusoidal capillarization in the mechanisms of diverse liver diseases were also showed. Finally, It would hopeful that this review can help to promote the studies on sinusoidal endothelial cells.%肝窦内皮细胞(liver sinusoidal endothelial cell,LSEC)是肝非实质细胞的主要细胞群,具有物质转运、吞噬、抗原提呈、免疫耐受等功能.肝在遭到多种病原侵袭时,肝窦内皮细胞窗孔逐渐减少或消失,内皮下基膜形成,产生类似于连续型毛细血管的结构,这一过程称为肝窦毛细血管化.它由多种因素引起,其过程极复杂,在多种肝病的发病前期阶段均有出现,近年来受到广泛关注.而目前关于肝窦内皮细胞的生理功能及病理机制研究方面的系统总结仍少有报道.本文对肝窦内皮细胞的生理功能及肝窦病理机制作一较为全面的综述.除了阐述肝窦毛细血管化自身分子机制的研究进展外,还重点介绍了肝窦毛细血管化参与肝多种疾病发病过程的作用机制.此外,对肝窦内皮细胞相关的研究

  5. Deoxynivalenol-Induced Proinflammatory Gene Expression: Mechanisms and Pathological Sequelae

    Directory of Open Access Journals (Sweden)

    James J. Pestka

    2010-06-01

    Full Text Available The trichothecene mycotoxin deoxynivalenol (DON is commonly encountered in human cereal foods throughout the world as a result of infestation of grains in the field and in storage by the fungus Fusarium. Significant questions remain regarding the risks posed to humans from acute and chronic DON ingestion, and how to manage these risks without imperiling access to nutritionally important food commodities. Modulation of the innate immune system appears particularly critical to DON’s toxic effects. Specifically, DON induces activation of mitogen-activated protein kinases (MAPKs in macrophages and monocytes, which mediate robust induction of proinflammatory gene expression—effects that can be recapitulated in intact animals. The initiating mechanisms for DON-induced ribotoxic stress response appear to involve the (1 activation of constitutive protein kinases on the damaged ribosome and (2 autophagy of the chaperone GRP78 with consequent activation of the ER stress response. Pathological sequelae resulting from chronic low dose exposure include anorexia, impaired weight gain, growth hormone dysregulation and aberrant IgA production whereas acute high dose exposure evokes gastroenteritis, emesis and a shock-like syndrome. Taken together, the capacity of DON to evoke ribotoxic stress in mononuclear phagocytes contributes significantly to its acute and chronic toxic effects in vivo. It is anticipated that these investigations will enable the identification of robust biomarkers of effect that will be applicable to epidemiological studies of the human health effects of this common mycotoxin.

  6. Physiological and pathological factors and mechanisms in the process of root resorption in primary teeth

    Directory of Open Access Journals (Sweden)

    Bianca Zimmermann Santos

    2010-07-01

    Full Text Available Introduction: Tooth resorption is essential in the process of root resorption in primary teeth. However, pathological root resorption, mainly the inflammatory one, is a consequence and/or complication of several clinical conditions, such as dental trauma and periapical inflammatory lesions from dental caries, thus becoming a common cause of tooth loss. Objective: To present and discuss a literature review regarding the mechanisms of physiological and inflammatory pathological root resorption in primary teeth, emphasizing their biochemical and cellular events. Literature review: The odontoclasts cells are responsible for resorption of dental tissues, and they are influenced by several stimuli and molecular signals derived from cytokines, neuropeptides, hormones and degradation products released when tissue is injured. However, so far it is not clear what leads to the differentiation of the precursor cells of odontoclasts, what gives them the signal to start the resorption in a specific place and time (especially in primary teeth and why they are activated in some pathological conditions,but not in others.Conclusion: The knowledge regarding molecular mechanisms and factors that regulate the process of root resorption is still meager.Research in this area is of great relevance,since new knowledge about the molecular pathway(s involved in root resorption may allow the development of different therapies, more biological ones, in order to control or prevent resorption, thus preventing tooth loss and its consequences.

  7. Molecular modifiers reveal a mechanism of pathological crystal growth inhibition

    Science.gov (United States)

    Chung, Jihae; Granja, Ignacio; Taylor, Michael G.; Mpourmpakis, Giannis; Asplin, John R.; Rimer, Jeffrey D.

    2016-08-01

    Crystalline materials are crucial to the function of living organisms, in the shells of molluscs, the matrix of bone, the teeth of sea urchins, and the exoskeletons of coccoliths. However, pathological biomineralization can be an undesirable crystallization process associated with human diseases. The crystal growth of biogenic, natural and synthetic materials may be regulated by the action of modifiers, most commonly inhibitors, which range from small ions and molecules to large macromolecules. Inhibitors adsorb on crystal surfaces and impede the addition of solute, thereby reducing the rate of growth. Complex inhibitor-crystal interactions in biomineralization are often not well elucidated. Here we show that two molecular inhibitors of calcium oxalate monohydrate crystallization—citrate and hydroxycitrate—exhibit a mechanism that differs from classical theory in that inhibitor adsorption on crystal surfaces induces dissolution of the crystal under specific conditions rather than a reduced rate of crystal growth. This phenomenon occurs even in supersaturated solutions where inhibitor concentration is three orders of magnitude less than that of the solute. The results of bulk crystallization, in situ atomic force microscopy, and density functional theory studies are qualitatively consistent with a hypothesis that inhibitor-crystal interactions impart localized strain to the crystal lattice and that oxalate and calcium ions are released into solution to alleviate this strain. Calcium oxalate monohydrate is the principal component of human kidney stones and citrate is an often-used therapy, but hydroxycitrate is not. For hydroxycitrate to function as a kidney stone treatment, it must be excreted in urine. We report that hydroxycitrate ingested by non-stone-forming humans at an often-recommended dose leads to substantial urinary excretion. In vitro assays using human urine reveal that the molecular modifier hydroxycitrate is as effective an inhibitor of nucleation

  8. Molecular modifiers reveal a mechanism of pathological crystal growth inhibition

    Science.gov (United States)

    Chung, Jihae; Granja, Ignacio; Taylor, Michael G.; Mpourmpakis, Giannis; Asplin, John R.; Rimer, Jeffrey D.

    2016-08-01

    Crystalline materials are crucial to the function of living organisms, in the shells of molluscs, the matrix of bone, the teeth of sea urchins, and the exoskeletons of coccoliths. However, pathological biomineralization can be an undesirable crystallization process associated with human diseases. The crystal growth of biogenic, natural and synthetic materials may be regulated by the action of modifiers, most commonly inhibitors, which range from small ions and molecules to large macromolecules. Inhibitors adsorb on crystal surfaces and impede the addition of solute, thereby reducing the rate of growth. Complex inhibitor–crystal interactions in biomineralization are often not well elucidated. Here we show that two molecular inhibitors of calcium oxalate monohydrate crystallization—citrate and hydroxycitrate—exhibit a mechanism that differs from classical theory in that inhibitor adsorption on crystal surfaces induces dissolution of the crystal under specific conditions rather than a reduced rate of crystal growth. This phenomenon occurs even in supersaturated solutions where inhibitor concentration is three orders of magnitude less than that of the solute. The results of bulk crystallization, in situ atomic force microscopy, and density functional theory studies are qualitatively consistent with a hypothesis that inhibitor–crystal interactions impart localized strain to the crystal lattice and that oxalate and calcium ions are released into solution to alleviate this strain. Calcium oxalate monohydrate is the principal component of human kidney stones and citrate is an often-used therapy, but hydroxycitrate is not. For hydroxycitrate to function as a kidney stone treatment, it must be excreted in urine. We report that hydroxycitrate ingested by non-stone-forming humans at an often-recommended dose leads to substantial urinary excretion. In vitro assays using human urine reveal that the molecular modifier hydroxycitrate is as effective an inhibitor of

  9. Parkinson disease: from pathology to molecular disease mechanisms.

    Science.gov (United States)

    Dexter, David T; Jenner, Peter

    2013-09-01

    Parkinson disease (PD) is a complex neurodegenerative disorder with both motor and nonmotor symptoms owing to a spreading process of neuronal loss in the brain. At present, only symptomatic treatment exists and nothing can be done to halt the degenerative process, as its cause remains unclear. Risk factors such as aging, genetic susceptibility, and environmental factors all play a role in the onset of the pathogenic process but how these interlink to cause neuronal loss is not known. There have been major advances in the understanding of mechanisms that contribute to nigral dopaminergic cell death, including mitochondrial dysfunction, oxidative stress, altered protein handling, and inflammation. However, it is not known if the same processes are responsible for neuronal loss in nondopaminergic brain regions. Many of the known mechanisms of cell death are mirrored in toxin-based models of PD, but neuronal loss is rapid and not progressive and limited to dopaminergic cells, and drugs that protect against toxin-induced cell death have not translated into neuroprotective therapies in humans. Gene mutations identified in rare familial forms of PD encode proteins whose functions overlap widely with the known molecular pathways in sporadic disease and these have again expanded our knowledge of the neurodegenerative process but again have so far failed to yield effective models of sporadic disease when translated into animals. We seem to be missing some key parts of the jigsaw, the trigger event starting many years earlier in the disease process, and what we are looking at now is merely part of a downstream process that is the end stage of neuronal death.

  10. Natural killer T (NKT cells accelerate Shiga toxin type 2 (Stx2 pathology in mice

    Directory of Open Access Journals (Sweden)

    Fumiko eObata

    2015-04-01

    Full Text Available Shiga toxin-producing Escherichia coli (STEC is a leading cause of childhood renal disease He-molytic Uremic Syndrome (HUS. The involvement of renal cytokines and chemokines is sus-pected to play a critical role in disease progression. In current article, we tested the hypothesis that NKT cells are involved in Stx2-induced pathology in vivo. To address this hypothesis we compared Stx2 toxicity in WT and CD1 knockout (KO mice. In CD1KO mice, which lack nat-ural killer T (NKT cells, Stx2-induced pathologies such as weight loss, renal failure, and death were delayed. In WT mice, Stx2-specific selective increase in urinary albumin occurs in later time points, and this was also delayed in NKT cell deficient mice. NKT cell-associated cytokines such as IL-2, IL-4, IFN-γ and IL-17 were detected in kidney lysates of Stx2-injected WT mice with the peak around 36 h after Stx2 injection. In CD1KO, there was a delay in the kinetics, and increases in these cytokines were observed 60 h post Stx2 injection. These data suggest that NKT cells accelerate Stx2-induced pathology in mouse kidneys. To determine the mechanism by which NKT cells promote Stx2-associated disease, in vitro studies were performed using murine renal cells. We found that murine glomerular endothelial cells and podocytes express functional CD1d molecules and can present exogenous antigen to NKT cells. Moreover, we observed the direct interaction between Stx2 and the receptor Gb3 on the surface of mouse renal cells by 3D STORM-TIRF which provides single molecule imaging. Collectively, these data suggest that Stx2 binds to Gb3 on renal cells and leads to aberrant CD1d-mediated NKT cell activation. Therefore, strategies targeting NKT cells could have a significant impact on Stx2-associated renal pathology in STEC disease.

  11. Mechanical plasticity of cells

    Science.gov (United States)

    Bonakdar, Navid; Gerum, Richard; Kuhn, Michael; Spörrer, Marina; Lippert, Anna; Schneider, Werner; Aifantis, Katerina E.; Fabry, Ben

    2016-10-01

    Under mechanical loading, most living cells show a viscoelastic deformation that follows a power law in time. After removal of the mechanical load, the cell shape recovers only incompletely to its original undeformed configuration. Here, we show that incomplete shape recovery is due to an additive plastic deformation that displays the same power-law dynamics as the fully reversible viscoelastic deformation response. Moreover, the plastic deformation is a constant fraction of the total cell deformation and originates from bond ruptures within the cytoskeleton. A simple extension of the prevailing viscoelastic power-law response theory with a plastic element correctly predicts the cell behaviour under cyclic loading. Our findings show that plastic energy dissipation during cell deformation is tightly linked to elastic cytoskeletal stresses, which suggests the existence of an adaptive mechanism that protects the cell against mechanical damage.

  12. A microglial hypothesis of globoid cell leukodystrophy pathology.

    Science.gov (United States)

    Nicaise, Alexandra M; Bongarzone, Ernesto R; Crocker, Stephen J

    2016-11-01

    Globoid cell leukodystrophy (GLD), also known as Krabbe's disease, is a fatal demyelinating disease accompanied by the formation of giant, multinucleated cells called globoid cells. Previously believed to be a byproduct of inflammation, these cells can be found early in disease before evidence of any damage. The precise mechanism by which these globoid cells cause oligodendrocyte dysfunction is not completely understood, nor is their cell type defined. This Review outlines the idea that microglial cells are transformed into an unknown and undefined novel M3 phenotype in GLD, which is cytotoxic to oligodendrocytes, leading to disease progression. © 2016 Wiley Periodicals, Inc. PMID:27638591

  13. Pathological cyclic strain-induced apoptosis in human periodontal ligament cells through the RhoGDIα/caspase-3/PARP pathway.

    Directory of Open Access Journals (Sweden)

    Li Wang

    Full Text Available AIM: Human periodontal ligament (PDL cells incur changes in morphology and express proteins in response to cyclic strain. However, it is not clear whether cyclic strain, especially excessive cyclic strain, induces PDL cell apoptosis and if so, what mechanism(s are responsible. The aim of the present study was to elucidate the molecular mechanisms by which pathological levels of cyclic strain induce human PDL cell apoptosis. MATERIALS AND METHODS: Human PDL cells were obtained from healthy premolar tissue. After three to five passages in culture, the cells were subjected to 20% cyclic strain at a frequency of 0.1 Hz for 6 or 24 h using an FX-5000T system. Morphological changes of the cells were assessed by inverted phase-contrast microscopy, and apoptosis was detected by fluorescein isothiocyanate (FITC-conjugated annexin V and propidium iodide staining followed by flow cytometry. Protein expression was evaluated by Western blot analysis. RESULTS: The number of apoptotic human PDL cells increased in a time-dependent manner in response to pathological cyclic strain. The stretched cells were oriented parallel to each another with their long axes perpendicular to the strain force vector. Cleaved caspase-3 and poly-ADP-ribose polymerase (PARP protein levels increased in response to pathological cyclic strain over time, while Rho GDP dissociation inhibitor alpha (RhoGDIα decreased. Furthermore, knock-down of RhoGDIα by targeted siRNA transfection increased stretch-induced apoptosis and upregulated cleaved caspase-3 and PARP protein levels. Inhibition of caspase-3 prevented stretch-induced apoptosis, but did not change RhoGDIα protein levels. CONCLUSION: The overall results suggest that pathological-level cyclic strain not only influenced morphology but also induced apoptosis in human PDL cells through the RhoGDIα/caspase-3/PARP pathway. Our findings provide novel insight into the mechanism of apoptosis induced by pathological cyclic strain in

  14. The Pathology of T Cells in Systemic Lupus Erythematosus

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    Anselm Mak

    2014-01-01

    Full Text Available Systemic lupus erythematosus (SLE is characterized by the production of a wide array of autoantibodies. Thus, the condition was traditionally classified as a “B-cell disease”. Compelling evidence has however shown that without the assistance of the helper T lymphocytes, it is indeed difficult for the “helpless” B cells to become functional enough to trigger SLE-related inflammation. T cells have been recognized to be crucial in the pathogenicity of SLE through their capabilities to communicate with and offer enormous help to B cells for driving autoantibody production. Recently, a number of phenotypic and functional alterations which increase the propensity to trigger lupus-related inflammation have been identified in lupus T cells. Here, potential mechanisms involving alterations in T-cell receptor expressions, postreceptor downstream signalling, epigenetics, and oxidative stress which favour activation of lupus T cells will be discussed. Additionally, how regulatory CD4+, CD8+, and γδ T cells tune down lupus-related inflammation will be highlighted. Lastly, while currently available outcomes of clinical trials evaluating therapeutic agents which manipulate the T cells such as calcineurin inhibitors indicate that they are at least as efficacious and safe as conventional immunosuppressants in treating lupus glomerulonephritis, larger clinical trials are undoubtedly required to validate these as-yet favourable findings.

  15. The mechanics of cell protrusion

    Science.gov (United States)

    Danuser, Gaudenz

    2006-03-01

    The protrusion of the cell edge is the first step in a cycle of molecular processes that drive cell movements during development, immune responses, wound healing and many other physiological functions. It is also the earliest pathological event observed during metastasis of cancer. Textbook models associate protrusion with the assembly of an actin polymer network subadjacent to the cell plasma membrane. However, for this process to be transformed into edge advancement, polymerization-induced forces need to be balanced by adhesion complexes that link the actin network to the extracellular domain. Also, the effectiveness of network assembly in mediating forward movement of the cell edge depends on how contraction forces pull the network in the cell front retrogradly towards the cell center. Thus, what is observed in a microscope as cell protrusion reflects the kinematic output of at least three space- and time-modulated mechanisms of force generation. The coordination of these machineries is thought to be regulated by a complex network of mechano-chemical signals. Our goal is to establish the contributions of each those mechanisms and their control by reconstructing the spatiotemporal distribution of intracellular forces via inverse dynamics and molecular intervention with the relevant signalling pathways. To this end, we have developed quantitative Fluorescent Speckle Microscopy (qFSM) which provides high-resolution spatiotemporal measurements of actin network deformation and material properties in migrating cells. In addition, qFSM delivers maps of cytoskeleton assembly and disassembly, so that we can infer the plasticity of the material in situ. Together, this data allows us to deduce intracellular force distributions from the constitutive laws of strain and stress in the actin polymer network. Using this approach we discovered that unperturbed cells protrude in a dynamic steady state where periodic patterns of network assembly, adhesion formation, and

  16. Mechanical shielded hot cell

    International Nuclear Information System (INIS)

    A plan to erect a mechanical shielded hot cell in the process hall of the Radiochemical Laboratory at Inchas is described. The hot cell is designed for safe handling of spent fuel bundles, from the Inchas reactor, and for dismantling and cutting the fuel rods in preparation for subsequent treatment. The biological shielding allows for the safe handling of a total radioactivity level up to 10,000 MeV-Ci. The hot cell consists of an α-tight stainless-steel box, connected to a γ-shielded SAS, through an air-lock containing a movable carriage. The α-box is tightly connected with six dry-storage cavities for adequate storage of the spent fuel bundles. Both the α-box, with the dry-storage cavities, and the SAS are surrounded by 200-mm thick biological lead shielding. The α-box is equipped with two master-slave manipulators, a lead-glass window, a monorail crane and Padirac and Minirag systems. The SAS is equipped with a lead-glass window, tong manipulator, a shielded pit and a mechanism for the entry of the spent fuel bundle. The hot cell is served by adequate ventilation and monitoring systems. (author)

  17. Glioma-initiating cells and molecular pathology: implications for therapy.

    Science.gov (United States)

    Natsume, Atsushi; Kinjo, Sayano; Yuki, Kanako; Kato, Takenori; Ohno, Masasuke; Motomura, Kazuya; Iwami, Kenichiro; Wakabayashi, Toshihiko

    2011-02-01

    There is now compelling evidence that gliomas harbor a small population of cells, termed glioma-initiating cells (GICs), characterized by their ability to undergo self-renewal and initiate tumorigenesis. The development of therapeutic strategies targeted toward GIC signaling may improve the treatment of malignant gliomas. The characterization of GICs provides a clue to elucidating histological heterogeneity and treatment failure. The role of the stem cell marker CD133 in the initiation and progression of brain tumors is still uncertain. Here, we review some of the signaling mechanisms involved in GIC biology, such as phosphatase and tensin homolog (PTEN), sonic hedgehog, Notch, and WNT signaling pathways, maternal embryonic leucine-zipper kinase (MELK), BMI1, and Janus kinase signal transducer and activator of transcription (JAK-STAT) signaling. In addition, we discuss the role of microRNAs in GICs by focusing on microRNA-21 regulation by type I interferon.

  18. Molecular Pathology of Adult T-Cell Leukemia/Lymphoma.

    Science.gov (United States)

    Ohshima, Koichi

    2015-01-01

    , the chronic cases with cell cycle deregulation and disruption of immunosurveillance mechanism were associated with faster progression to acute ATLL. Immune evasion, microenvironment, and genetic alteration are therefore important in the multi-step progression of ATLL lymphomagenesis. PMID:26550829

  19. Structure-mechanism-based engineering of chemical regulators targeting distinct pathological factors in Alzheimer's disease

    Science.gov (United States)

    Beck, Michael W.; Derrick, Jeffrey S.; Kerr, Richard A.; Oh, Shin Bi; Cho, Woo Jong; Lee, Shin Jung C.; Ji, Yonghwan; Han, Jiyeon; Tehrani, Zahra Aliakbar; Suh, Nayoung; Kim, Sujeong; Larsen, Scott D.; Kim, Kwang S.; Lee, Joo-Yong; Ruotolo, Brandon T.; Lim, Mi Hee

    2016-10-01

    The absence of effective therapeutics against Alzheimer's disease (AD) is a result of the limited understanding of its multifaceted aetiology. Because of the lack of chemical tools to identify pathological factors, investigations into AD pathogenesis have also been insubstantial. Here we report chemical regulators that demonstrate distinct specificity towards targets linked to AD pathology, including metals, amyloid-β (Aβ), metal-Aβ, reactive oxygen species, and free organic radicals. We obtained these chemical regulators through a rational structure-mechanism-based design strategy. We performed structural variations of small molecules for fine-tuning their electronic properties, such as ionization potentials and mechanistic pathways for reactivity towards different targets. We established in vitro and/or in vivo efficacies of the regulators for modulating their targets' reactivities, ameliorating toxicity, reducing amyloid pathology, and improving cognitive deficits. Our chemical tools show promise for deciphering AD pathogenesis and discovering effective drugs.

  20. Transplantation of human amniotic epithelial cells repairs brachial plexus injury:pathological and biomechanical analyses

    Institute of Scientific and Technical Information of China (English)

    Qi Yang; Min Luo; Peng Li; Hai Jin

    2014-01-01

    A brachial plexus injury model was established in rabbits by stretching the C6 nerve root. Imme-diately after the stretching, a suspension of human amniotic epithelial cells was injected into the injured brachial plexus. The results of tensile mechanical testing of the brachial plexus showed that the tensile elastic limit strain, elastic limit stress, maximum stress, and maximum strain of the injured brachial plexuses were signiifcantly increased at 24 weeks after the injection. The treat-ment clearly improved the pathological morphology of the injured brachial plexus nerve, as seen by hematoxylin eosin staining, and the functions of the rabbit forepaw were restored. These data indicate that the injection of human amniotic epithelial cells contributed to the repair of brachial plexus injury, and that this technique may transform into current clinical treatment strategies.

  1. Design of CMOS Based Image Sensor with Cantilever Mechanism for Smart Pathological Detection with Opto-Mechanical System

    Directory of Open Access Journals (Sweden)

    Rajeshlaik

    2012-06-01

    Full Text Available patient immobilized on slide under the microscope is extracted with imaging device. Similar kind of setup is designed to detect object with analog transducer circuit system which the mines worker use torchlight over the helmet underground with 4.5 volt of light, with 1 watt bulb is sufficient our Eye can recognize the object, but with CFL it is more brighter in dark condition to detect the object. Here the biomechanical action of the miners Eye & brain coordination inside the mining region where it is very dark to focus the object, the inverter like headlight operates in this condition and helps him to work smoothly for his neural coordination works in balanced. Focal length inversely proportional to the magnification is required to clearly visualize any object, Physically when we see any object we move nearer or far-away and maintain the distance from the object, if any person cannot clearly identify they wear glass of varying power as per their disorder, Electronic CMOS Biosensor with signal conditioning OPAMP gives the strong power to the eye to visualize the image under the microscope converting the charge of APS into the voltage amplified in a nano-second time response. The inverting action of the Eye with 01,which is simulated for Photo-sensor circuit, with equivalent silicon-on-chip based CMOS combination. Thus the detection of cancer cells is very cheap and efficient way in pathological laboratory with CMOS microscope. Comparative studies makes the efficient detection of morphological features of gross tissue section of tumor Cells clearly detected when magnified under 40 x,with CMOS biosensor phototransistor. Patient requires to check his or her body weight, prior to pathological check up, therefore the weighing machine is the very important piezo convertor of mechanical energy of the body into weight and when the smart nano-mechanical cantilever sensor chip integrates with this machine the signal will be more fast .The PH paper as a

  2. Bone marrow-derived cells are differentially involved in pathological and physiological retinal angiogenesis in mice

    International Nuclear Information System (INIS)

    Purpose: Bone marrow-derived cells have been shown to play roles in angiogenesis. Although these cells have been shown to promote angiogenesis, it is not yet clear whether these cells affect all types of angiogenesis. This study investigated the involvement of bone marrow-derived cells in pathological and physiological angiogenesis in the murine retina. Materials and methods: The oxygen-induced retinopathy (OIR) model was used as a retinal angiogenesis model in newborn mice. To block the influence of bone marrow-derived cells, the mice were irradiated with a 4-Gy dose of radiation from a 137Cs source. Irradiation was performed in four different conditions with radio dense 2-cm thick lead disks; (1) H group, the head were covered with these discs to protect the eyes from radiation; (2) A group, all of the body was covered with these discs; (3) N group, mice were completely unshielded; (4) C group, mice were put in the irradiator but were not irradiated. On P17, the retinal areas showing pathological and physiological retinal angiogenesis were measured and compared to the retinas of nonirradiated mice. Results: Although irradiation induced leukocyte depletion, it did not affect the number of other cell types or body weight. Retinal nonperfusion areas were significantly larger in irradiated mice than in control mice (P < 0.05), indicating that physiological angiogenesis was impaired. However, the formation of tuft-like angiogenesis processes was more prominent in the irradiated mice (P < 0.05), indicating that pathological angiogenesis was intact. Conclusions: Bone marrow-derived cells seem to be differentially involved in the formation of physiological and pathological retinal vessels. Pathological angiogenesis in the murine retina does not require functional bone marrow-derived cells, but these cells are important for the formation of physiological vessels. Our results add a new insight into the pathology of retinal angiogenesis and bolster the hypothesis that bone

  3. Placental vascular pathology and increased thrombin generation as mechanisms of disease in obstetrical syndromes

    Directory of Open Access Journals (Sweden)

    Salvatore Andrea Mastrolia

    2014-11-01

    Full Text Available Obstetrical complications including preeclampsia, fetal growth restriction, preterm labor, preterm prelabor rupture of membranes and fetal demise are all the clinical endpoint of several underlying mechanisms (i.e., infection, inflammation, thrombosis, endocrine disorder, immunologic rejection, genetic, and environmental, therefore, they may be regarded as syndromes. Placental vascular pathology and increased thrombin generation were reported in all of these obstetrical syndromes. Moreover, elevated concentrations of thrombin-anti thrombin III complexes and changes in the coagulation as well as anticoagulation factors can be detected in the maternal circulation prior to the clinical development of the disease in some of these syndromes. In this review, we will assess the changes in the hemostatic system during normal and complicated pregnancy in maternal blood, maternal–fetal interface and amniotic fluid, and describe the contribution of thrombosis and vascular pathology to the development of the great obstetrical syndromes.

  4. Mechanically facilitated cell-cell electrofusion.

    OpenAIRE

    Jaroszeski, M. J.; Gilbert, R.; Fallon, P.G.; Heller, R

    1994-01-01

    Apparatus and methods were developed to enable mechanically facilitated cell-cell electrofusion to be performed. The apparatus and methods mechanically place cells in contact before fusion. The key component of this fusion system was a newly developed fusion chamber. The chamber was composed of two functionally identical electrodes that were housed in a multi-layer structure. The layers functioned as support for the electrodes. They also allowed adjustment of the distance between opposing ele...

  5. Cell mechanics as a marker for diseases: Biomedical applications of AFM

    Science.gov (United States)

    Rianna, Carmela; Radmacher, Manfred

    2016-08-01

    Many diseases are related to changes in cell mechanics. Atomic Force Microscopy (AFM) is one of the most suitable techniques allowing the investigation of both topography and mechanical properties of adherent cells with high spatial resolution under physiological conditions. Over the years the use of this technique in medical and clinical applications has largely increased, resulting in the notion of cell mechanics as a biomarker to discriminate between different physiological and pathological states of cells. Cell mechanics has proven to be a biophysical fingerprint able discerning between cell phenotypes, unraveling processes in aging or diseases, or even detecting and diagnosing cellular pathologies. We will review in this report some of the works on cell mechanics investigated by AFM with clinical and medical relevance in order to clarify the state of research in this field and to highlight the role of cell mechanics in the study of pathologies, focusing on cancer, blood and cardiovascular diseases.

  6. Innate lymphoid cells drive interleukin-23-dependent innate intestinal pathology

    OpenAIRE

    Buonocore, Sofia; Ahern, Philip P.; Uhlig, Holm H; Ivanov, Ivaylo I.; Dan R. Littman; Maloy, Kevin J.; Powrie, Fiona

    2010-01-01

    The key role of IL-23 in the pathogenesis of autoimmune and chronic inflammatory disorders is supported by the identification of IL-23R susceptibility alleles associated with IBD, psoriasis and ankylosing spondylitis. IL-23 driven inflammation has primarily been linked to the actions of Th17 cells 1 . Somewhat overlooked, IL-23 also has inflammatory effects on innate immune cells 2 and can drive T cell- independent colitis. However the downstream cellular and molecular pathways involved in th...

  7. Injurious mechanical ventilation in the normal lung causes a progressive pathologic change in dynamic alveolar mechanics

    OpenAIRE

    Pavone, Lucio A; Albert, Scott; Carney, David; Gatto, Louis A; Halter, Jeffrey M; Nieman, Gary F.

    2007-01-01

    Introduction Acute respiratory distress syndrome causes a heterogeneous lung injury, and without protective mechanical ventilation a secondary ventilator-induced lung injury can occur. To ventilate noncompliant lung regions, high inflation pressures are required to 'pop open' the injured alveoli. The temporal impact, however, of these elevated pressures on normal alveolar mechanics (that is, the dynamic change in alveolar size and shape during ventilation) is unknown. In the present study we ...

  8. Cancer stem cell: fundamental experimental pathological concepts and updates.

    Science.gov (United States)

    Islam, Farhadul; Qiao, Bin; Smith, Robert A; Gopalan, Vinod; Lam, Alfred K-Y

    2015-04-01

    Cancer stem cells (CSCs) are a subset of cancer cells which play a key role in predicting the biological aggressiveness of cancer due to its ability of self-renewal and multi-lineage differentiation (stemness). The CSC model is a dynamic one with a functional subpopulation of cancer cells rather than a stable cell population responsible for tumour regeneration. Hypotheses regarding the origins of CSCs include (1) malignant transformation of normal stem cells; (2) mature cancer cell de-differentiation with epithelial-mesenchymal transition and (3) induced pluripotent cancer cells. Surprisingly, the cancer stem cell hypothesis originated in the late nineteenth century and the existence of haematopoietic stem cells was demonstrated a century later, demonstrating that the concept was possible. In the last decade, CSCs have been identified and isolated in different cancers. The hallmark traits of CSCs include their heterogeneity, interaction with microenvironments and plasticity. Understanding these basic concepts of CSCs is important for translational applications using CSCs in the management of patients with cancer. PMID:25659759

  9. Tumor necrosis factor alpha production from CD8+ T cells mediates oviduct pathological sequelae following primary genital Chlamydia muridarum infection.

    Science.gov (United States)

    Murthy, Ashlesh K; Li, Weidang; Chaganty, Bharat K R; Kamalakaran, Sangamithra; Guentzel, M Neal; Seshu, J; Forsthuber, Thomas G; Zhong, Guangming; Arulanandam, Bernard P

    2011-07-01

    The immunopathogenesis of Chlamydia trachomatis-induced oviduct pathological sequelae is not well understood. Mice genetically deficient in perforin (perforin(-/-) mice) or tumor necrosis factor alpha (TNF-α) production (TNF-α(-/-) mice) displayed comparable vaginal chlamydial clearance rates but significantly reduced oviduct pathology (hydrosalpinx) compared to that of wild-type mice. Since both perforin and TNF-α are effector mechanisms of CD8(+) T cells, we evaluated the role of CD8(+) T cells during genital Chlamydia muridarum infection and oviduct sequelae. Following vaginal chlamydial challenge, (i) mice deficient in TAP I (and therefore the major histocompatibility complex [MHC] I pathway and CD8(+) T cells), (ii) wild-type mice depleted of CD8(+) T cells, and (iii) mice genetically deficient in CD8 (CD8(-/-) mice) all displayed similar levels of vaginal chlamydial clearance but significantly reduced hydrosalpinx, compared to those of wild-type C57BL/6 mice, suggesting a role for CD8(+) T cells in chlamydial pathogenesis. Repletion of CD8(-/-) mice with wild-type or perforin(-/-), but not TNF-α(-/-), CD8(+) T cells at the time of challenge restored hydrosalpinx to levels observed in wild-type C57BL/6 mice, suggesting that TNF-α production from CD8(+) T cells is important for pathogenesis. Additionally, repletion of TNF-α(-/-) mice with TNF-α(+/+) CD8(+) T cells significantly enhanced the incidence of hydrosalpinx and oviduct dilatation compared to those of TNF-α(-/-) mice but not to the levels found in wild-type mice, suggesting that TNF-α production from CD8(+) T cells and non-CD8(+) cells cooperates to induce optimal oviduct pathology following genital chlamydial infection. These results provide compelling new evidence supporting the contribution of CD8(+) T cells and TNF-α production to Chlamydia-induced reproductive tract sequelae.

  10. Complete pathological resolution of pulmonary Langerhans cell histiocytosis

    OpenAIRE

    Ninaber, Maarten; Dik, Hans; Peters, Elke

    2014-01-01

    Cigarette smoking is a major risk factor for pulmonary Langerhans cell histiocytosis (pLCH) and lung cancer. Resolution of pLCH may occur spontaneously, after smoking cessation or other interventions. However, despite clinicoradiological resolution, residual pulmonary Langerhans cells may be present and may lead to recurrent disease. We report the first case of pLCH with a complete histological resolution.

  11. B-Cell Pathology in Juvenile Idiopathic Arthritis

    Directory of Open Access Journals (Sweden)

    V. Wiegering

    2010-01-01

    Full Text Available Juvenile Idiopathic Arthritis (JIA is the most common cause of chronic arthritis in childhood and adolescents and encompasses a heterogeneous group of different diseases. Due to the promising results of B-cell depleting therapies in rheumatoid arthritis the role of B-cells in autoimmune diseases has to be discussed in a new context. Additionally, experiments in mouse models have shed new light on the antibody-independent role of B-cells in the development of autoimmune diseases. In this review we will discuss the importance of B-cells in the pathogenesis of JIA appraising the question for an immunological basis of B-cell targeted therapy in JIA.

  12. Musculoskeletal Pathology.

    Science.gov (United States)

    Peat, Frances J; Kawcak, Christopher E

    2015-08-01

    The current understanding of pathology as it relates to common diseases of the equine musculoskeletal system is reviewed. Conditions are organized under the fundamental categories of developmental, exercise-induced, infectious, and miscellaneous pathology. The overview of developmental pathology incorporates the new classification system of juvenile osteochondral conditions. Discussion of exercise-induced pathology emphasizes increased understanding of the contribution of cumulative microdamage caused by repetitive cyclic loading. Miscellaneous musculoskeletal pathology focuses on laminitis, which current knowledge indicates should be regarded as a clinical syndrome with a variety of possible distinct mechanisms of structural failure that are outlined in this overview. PMID:26037607

  13. Application of non-small cell lung cancer pleural effusion cell blocks in molecular pathological detection

    Institute of Scientific and Technical Information of China (English)

    Ying Zhang; Nan Jiang; Dongdong Qian; Xiangzhou Li; Yu Zhou; Jia Mei; Xiaohui Cao

    2014-01-01

    Objective:The tumor tissues used in molecular pathological detection were usual y obtained by surgery, which would cause trauma and may not be suitable for the terminal cancer patients. This paper evaluated the value of the non-smal celllung cancer (NSCLC) pleural ef usion cellblocks as tumor tissues replacement materials in the application of molecular pathological detection. Methods: Tumor cells were made into cellblocks through stratified centrifugal from 30 NSCLC pa-tients with the pleural ef usion. The immunohistochemistry, fluorescence in situ hybridization (FISH) and gene sequencing methods were employed in our experiments. Results:The tumor cells of cellblock section were rich and could keep part of histological structure. Immunohistochemistry staining could assist diagnosis and tumor parting. Epidermal growth factor receptor (EGFR) FISH-positive was found in 33.33%of the group, high polysomy in 6 cases, amplification in 4 cases. EGFR gene mutations were found in 8 cases of 30 samples, with an incidence of 26.67%, 6 cases were detected in the exon 19, and 2 cases were detected in the exon 21. Conclusion:The NSCLC pleural ef usion cellblocks are useful for the diagnosis and determining the primary source of tumor, instructed targeted therapy.

  14. An overview of multiphase cartilage mechanical modelling and its role in understanding function and pathology.

    Science.gov (United States)

    Klika, Václav; Gaffney, Eamonn A; Chen, Ying-Chun; Brown, Cameron P

    2016-09-01

    There is a long history of mathematical and computational modelling with the objective of understanding the mechanisms governing cartilage׳s remarkable mechanical performance. Nonetheless, despite sophisticated modelling development, simulations of cartilage have consistently lagged behind structural knowledge and thus the relationship between structure and function in cartilage is not fully understood. However, in the most recent generation of studies, there is an emerging confluence between our structural knowledge and the structure represented in cartilage modelling. This raises the prospect of further refinement in our understanding of cartilage function and also the initiation of an engineering-level understanding for how structural degradation and ageing relates to cartilage dysfunction and pathology, as well as informing the potential design of prospective interventions. Aimed at researchers entering the field of cartilage modelling, we thus review the basic principles of cartilage models, discussing the underlying physics and assumptions in relatively simple settings, whilst presenting the derivation of relatively parsimonious multiphase cartilage models consistent with our discussions. We proceed to consider modern developments that start aligning the structure captured in the models with observed complexities. This emphasises the challenges associated with constitutive relations, boundary conditions, parameter estimation and validation in cartilage modelling programmes. Consequently, we further detail how both experimental interrogations and modelling developments can be utilised to investigate and reduce such difficulties before summarising how cartilage modelling initiatives may improve our understanding of cartilage ageing, pathology and intervention. PMID:27195911

  15. A review of novel optical imaging strategies of the stroke pathology and stem cell therapy in stroke

    Directory of Open Access Journals (Sweden)

    Markus eAswendt

    2014-08-01

    Full Text Available Transplanted stem cells can induce and enhance functional recovery in experimental stroke. Invasive analysis has been extensively used to provide detailed cellular and molecular characterization of the stroke pathology and engrafted stem cells. But post mortem analysis is not appropriate to reveal the time scale of the dynamic interplay between the cell graft, the ischemic lesion and the endogenous repair mechanisms. This review describes non-invasive imaging techniques which have been developed to provide complementary in vivo information. Recent advances were made in analyzing simultaneously different aspects of the cell graft (e.g. number of cells, viability state and cell fate, the ischemic lesion (e.g. blood brain barrier consistency, hypoxic and necrotic areas and the neuronal and vascular network. We focus on optical methods, which permit simple animal preparation, repetitive experimental conditions, relatively medium-cost instrumentation and are performed under mild anesthesia, thus nearly under physiological conditions. A selection of recent examples of optical intrinsic imaging, fluorescence imaging (FLI and bioluminescence imaging (BLI to characterize the stroke pathology and engrafted stem cells are discussed. Special attention is paid to novel optimal reporter genes/probes for genetic labeling and tracking of stem cells and appropriate transgenic animal models. Requirements, advantages and limitations of these imaging platforms are critically discussed and placed into the context of other non-invasive techniques, e.g. magnetic resonance imaging (MRI and positron emission tomography (PET, which can be joined with optical imaging in multimodal approaches.

  16. Mediastinal germ cell tumors: a radiologic-pathologic review

    Energy Technology Data Exchange (ETDEWEB)

    Drevelegas, A. [Dept. of Radiology, Aristoteles Univ., Thessaloniki (Greece); Palladas, P. [Dept. of Radiology, G. Papanicolaou Hospital, Thessaloniki (Greece); Scordalaki, A. [Dept. of Pathology, G. Papanicolaou Hospital, Thessaloniki (Greece)

    2001-10-01

    Germ cell tumors of the mediastinum are histologically identical to those found in the testes and ovaries. Early diagnosis and treatment improve the survival rate. Imaging studies of teratoma demonstrate a rounded, often lobulated heterogeneous mass containing soft tissue elements with fluid and fat attenuation. Calcification is present in 20-43% of cases. Seminomas are large masses of homogeneous soft tissue attenuation. Malignant nonseminomatous germ cell tumors are heterogeneous tumors with irregular borders due to invasion of adjacent structures. CT shows the location and extent of the tumors as well as intrinsic elements including soft tissue, fat, fluid, and calcification. CT is the modality of choice for the diagnostic evaluation of these tumors. MRI reveals masses of heterogeneous signal intensity, is more sensitive in depicting infiltration of the adjacent structures by fat plane obliteration, and is performed as an ancillary study. (orig.)

  17. Comparison of prefrontal cell pathology between depression and alcohol dependence

    OpenAIRE

    Miguel-Hidalgo, José J.; Rajkowska, Grazyna

    2003-01-01

    Chronic alcohol abuse is often co-morbid with depression symptoms and in many cases it appears to induce major depressive disorder. Structural and functional neuroimaging has provided evidence supporting some degree of neuropathological convergence of alcoholism and mood disorders. In order to understand the cellular neuropathology of alcohol dependence and mood disorders, postmortem morphometric studies have tested the possibility of alterations in the number and size of cells in the prefron...

  18. Gene Expression Analysis of Human Vascular Endothelial Cells Treated by Ouabain in Pathological Concentration

    Institute of Scientific and Technical Information of China (English)

    任延平; 吕卓人

    2004-01-01

    Objectives To study the gene expression of human vascular endothelial cells (HUVEC) treated by ouabain in pathological concentration. Methods The response of endothelial cells to ouabain of 1.8 nmol/L was explored with a complementary DNA microarray representing 8 464 different human genes. Results The results of mRNA profiles analysis indicated that 129 of the genes were differently expressed, 26 were upregulated. Conclusions The pathological role of ouabain on HUVEC may be involved in the controlling of DNA transcription、protein translation、 metabolism and signal transduction.

  19. Pathological mechanisms of alcohol-induced hepatic portal hypertension in early stage fibrosis rat model

    Institute of Scientific and Technical Information of China (English)

    Jian Li; Jian-Zhao Niu; Ji-Feng Wang; Yu Li; Xiao-Hua Tao

    2005-01-01

    AIM: To study the role of hepatic sinusoidal capillarization and perisinusoidal fibrosis in rats with alcohol-induced portal hypertension and to discuss the pathological mechanisms of alcohol-induced hepatic portal hypertension.METHODS: Fifty SD rats were divided into control group (n=20) and model group (n=30). Alcoholic liver fibrosis rat model was induced by intragastric infusion of a mixture containing alcohol, corn oil and pyrazole (1 000:250:3). Fifteen rats in each group were killed at wk 16. The diameter and pressure of portal vein were measured. Plasma hyaluronic acid (HA), type Ⅳ collagen (CoⅣ) and laminin (LN) were determined by radioimmunoassay. Liver tissue was fixed in formalin (10%) and 6-μm thick sectiors were routinely stained with Mallory and Sirius Red. Liver tissue was treated with rabbit polyclonal antibody against LN and ColⅣ. Hepatic non-parenchymal cells were isolated,total protein was extracted and separated by SDS-PAGE.MMP-2 and TIMP-1 protein expression was estimated by Western blotting.RESULTS: The diameter (2.207 ± 0.096 vs 1.528 ± 0.054 mm, P<0.01) and pressure (11.014±0.395 vs 8.533±0.274 mmHg, P<0.01) of portal vein were significantly higher in model group than those in the control group. Plasma HA (129.97±16.10 vs 73.09±2.38 ng/mL, P<0.01), ColⅣ (210.49±4.36 vs 89.65±4.42 ng/mL, P<0.01) and LN (105.00±7.29 vs 55.70±4.32 ng/mL, P<0.01) were upregulated in model group. Abundant collagen deposited around the central vein of lobules, hepatic sinusoids and hepatocytes in model group. ColⅠ and ColⅢ increased remarkably and perisinusoids were almost surrounded by ColⅢ.Immunohistochemical staining showed that ColⅣ protein level (0.130±0.007 vs 0.032±0.004, P<0.01) and LN protein level (0.152±0.005 vs 0.029±0.005, P<0.01)were up-regulated remarkably in model group. MMP-2 protein expression (2.306±1.089 vs 0.612±0.081,P<0.01) and TIMP-1 protein expression (3.015±1.364 vs 0.446±0.009, P<0

  20. Langerhans' cell histiocytosis: pathology, imaging and treatment of skeletal involvement

    International Nuclear Information System (INIS)

    Langerhans' cell histiocytosis (LCH) is manifested in a variety of ways, the most common being the eosinophilic granuloma, a localized, often solitary bone lesion that occurs predominantly in the pediatric age group. The hallmark of LCH is the proliferation and accumulation of a specific histiocyte: the Langerhans' cell. In bone this may cause pain and adjacent soft-tissue swelling, but some lesions are asymptomatic. LCH can involve any bone, but most lesions occur in the skull (especially the calvarium and temporal bones), the pelvis, spine, mandible, ribs, and tubular bones. Imaging diagnosis of the disease in bone is first based on the plain radiographic appearance, which is usually a central destructive, aggressive-looking lesion. In the skull, the lesions develop in the diploic space, are lytic, and their edges may be beveled, scalloped or confluent (geographic), or show a ''button sequestrum.'' Vertebral body involvement usually causes collapse, resulting in vertebra plana. With significant recent improvements in the quality of gamma cameras, imaging techniques, and in studying children, bone scintigraphy at diagnosis and on follow-up usually reveals the sites of active disease, especially when the involvement is polyostotic. CT and MR imaging are very useful in providing detailed cross-sectional anatomic detail of the involved bone, including the bone marrow and the adjacent soft tissues. CT is better suited for demonstrating bone detail and MR imaging for bone marrow and soft-tissue involvement. (orig.)

  1. Endotoxin-induced basal respiration alterations of renal HK-2 cells: A sign of pathologic metabolism down-regulation

    Energy Technology Data Exchange (ETDEWEB)

    Quoilin, C., E-mail: cquoilin@ulg.ac.be [Laboratory of Biomedical Spectroscopy, Department of Physics, University of Liege, 4000 Liege (Belgium); Mouithys-Mickalad, A. [Center of Oxygen Research and Development, Department of Chemistry, University of Liege, 4000 Liege (Belgium); Duranteau, J. [Department of Anaesthesia and Surgical ICU, CHU Bicetre, University Paris XI Sud, 94275 Le Kremlin Bicetre (France); Gallez, B. [Biomedical Magnetic Resonance Group, Louvain Drug Research Institute, Universite catholique de Louvain, 1200 Brussels (Belgium); Hoebeke, M. [Laboratory of Biomedical Spectroscopy, Department of Physics, University of Liege, 4000 Liege (Belgium)

    2012-06-29

    Highlights: Black-Right-Pointing-Pointer A HK-2 cells model of inflammation-induced acute kidney injury. Black-Right-Pointing-Pointer Two oximetry methods: high resolution respirometry and ESR spectroscopy. Black-Right-Pointing-Pointer Oxygen consumption rates of renal cells decrease when treated with LPS. Black-Right-Pointing-Pointer Cells do not recover normal respiration when the LPS treatment is removed. Black-Right-Pointing-Pointer This basal respiration alteration is a sign of pathologic metabolism down-regulation. -- Abstract: To study the mechanism of oxygen regulation in inflammation-induced acute kidney injury, we investigate the effects of a bacterial endotoxin (lipopolysaccharide, LPS) on the basal respiration of proximal tubular epithelial cells (HK-2) both by high-resolution respirometry and electron spin resonance spectroscopy. These two complementary methods have shown that HK-2 cells exhibit a decreased oxygen consumption rate when treated with LPS. Surprisingly, this cellular respiration alteration persists even after the stress factor was removed. We suggested that this irreversible decrease in renal oxygen consumption after LPS challenge is related to a pathologic metabolic down-regulation such as a lack of oxygen utilization by cells.

  2. Endotoxin-induced basal respiration alterations of renal HK-2 cells: A sign of pathologic metabolism down-regulation

    International Nuclear Information System (INIS)

    Highlights: ► A HK-2 cells model of inflammation-induced acute kidney injury. ► Two oximetry methods: high resolution respirometry and ESR spectroscopy. ► Oxygen consumption rates of renal cells decrease when treated with LPS. ► Cells do not recover normal respiration when the LPS treatment is removed. ► This basal respiration alteration is a sign of pathologic metabolism down-regulation. -- Abstract: To study the mechanism of oxygen regulation in inflammation-induced acute kidney injury, we investigate the effects of a bacterial endotoxin (lipopolysaccharide, LPS) on the basal respiration of proximal tubular epithelial cells (HK-2) both by high-resolution respirometry and electron spin resonance spectroscopy. These two complementary methods have shown that HK-2 cells exhibit a decreased oxygen consumption rate when treated with LPS. Surprisingly, this cellular respiration alteration persists even after the stress factor was removed. We suggested that this irreversible decrease in renal oxygen consumption after LPS challenge is related to a pathologic metabolic down-regulation such as a lack of oxygen utilization by cells.

  3. Molecular pathology of mismatch repair deficient tumours with emphasis on immune escape mechanisms

    OpenAIRE

    Dierssen, Jan Willem Frederik

    2010-01-01

    This thesis describes molecular methods to distinguish separate colon tumour entities. Furthermore, it shows that distinct immune escape mechanisms, in particular distinct mechanisms of corrupting the HLA system, are operational in subsets of colon tumours. The apparent necessity of some colon tumours to circumvent the immune system might underscore the potential of immune based therapy approaches. Alternatively, it may suggest that such therapies will only lead to selection of tumour cells w...

  4. Characterization of T cell clones from chagasic patients: predominance of CD8 surface phenotype in clones from patients with pathology

    Directory of Open Access Journals (Sweden)

    Washington R. Cuna

    1995-08-01

    Full Text Available Human Chagas' disease, caused by the protozoan Trypanosoma cruzi, is associated with pathological processes whose mechanisms are not known. To address this question, T cell lines were developed from chronic chagasic patients peripheral blood mononuclear cells (PBMC and cloned. These T cell clones (TCC were analyzed phenotypically with monoclonal antibodies by the use of a fluorescence microscope. The surface phenotype of the TCC from the asymptomatic patient were predominantly CD4 positive (86%. On the contrary, the surface phenotype CD8 was predominant in the TCC from the patients suffering from cardiomegaly with right bundle branch block (83%, bradycardia with megacolon (75 % and bradycardia (75%. Future studies will be developed in order to identify the antigens eliciting these T cell subpopulations.

  5. Review: Animal Models of Diabetes Mellitus: Pathology and Mechanism of Some Diabetogenics

    Directory of Open Access Journals (Sweden)

    AGUNG ENDRO NUGROHO

    2006-10-01

    Full Text Available Animal models of diabetes mellitus were made and used in laboratorium according to the pathology of diabetic patient and its complications. Animal models of diabetes mellitus were designed by two methods: induced method such as pancreatectomy, chemicals (diabetogenic, viruses, and spontaneous method such BB (bio breeding rats and NOD (non-obese diabetic mice.The techniques of animal models of diabetes mellitus frequently used in the research were usage of diabetogenic such as alloxan and streptozotocin. Alloxan and its reduction metabolite (dialuric acid establish a redox cycle and form superoxide radicals, and they undergo dismutation to hydrogen peroxide. By Fenton reaction, the formation of reactive hydroxyl radicals was stimulated. These radicals with high concentration of cytosolic calcium cause rapid destruction of β cells. Besides, streptozotocin enters the β cell through a glucose transporter (GLUT2, and stimulates superoxide radicals, hydrogen peroxide and hydroxyl radicals which in turn causes rapid destruction of β cells. Streptozotocin also releases toxic amounts of nitric oxide that inhibits aconitase activity and contributes in DNA damage.

  6. On tensegrity in cell mechanics.

    Science.gov (United States)

    Volokh, K Y

    2011-09-01

    All models are wrong, but some are useful. This famous saying mirrors the situation in cell mechanics as well. It looks like no particular model of the cell deformability can be unconditionally preferred over others and different models reveal different aspects of the mechanical behavior of living cells. The purpose of the present work is to discuss the so-called tensegrity models of the cell cytoskeleton. It seems that the role of the cytoskeleton in the overall mechanical response of the cell was not appreciated until Donald Ingber put a strong emphasis on it. It was fortunate that Ingber linked the cytoskeletal structure to the fascinating art of tensegrity architecture. This link sparked interest and argument among biologists, physicists, mathematicians, and engineers. At some point the enthusiasm regarding tensegrity perhaps became overwhelming and as a reaction to that some skepticism built up. To demystify Ingber's ideas the present work aims at pinpointing the meaning of tensegrity and its role in our understanding of the importance of the cytoskeleton for the cell deformability and motility. It should be noted also that this paper emphasizes basic ideas rather than carefully follows the chronology of the development of tensegrity models. The latter can be found in the comprehensive review by Dimitrije Stamenovic (2006) to which the present work is complementary. PMID:21977516

  7. Optical diagnostics of tumour cells at different stages of pathology development

    Energy Technology Data Exchange (ETDEWEB)

    Shcheglova, L S; Maryakhina, V S [Orenburg State University, Orenburg (Russian Federation); Abramova, L L [Orenburg State Agrarian University, Orenburg (Russian Federation)

    2013-11-30

    The differences in optical and biophysical properties between the cells of mammary gland tumour extracted from tumours of different diameter are described. It is shown that the spectral and spectrokinetic properties of fluorescent probes in the cells extracted from the tumours 1 – 3 cm in diameter are essentially different. Thus, the extinction coefficient of rhodamine 6G gradually increases with the pathology development. At the same time the rate of interaction of the triplet states of molecular probes with the oxygen, diluted in the tumour cells cytoplasm, decreases with the growth of the tumour capsule diameter. The observed regularities can be due to the changes in the cell structure, biochemical and biophysical properties. The reported data may be useful for developing optical methods of diagnostics of biotissue pathological conditions. (optical methods in biology and medicine)

  8. Balancing immune protection and immune pathology by CD8+ T cell responses to influenza infection

    Directory of Open Access Journals (Sweden)

    Susu eDuan

    2016-02-01

    Full Text Available Influenza A virus (IAV is a significant human pathogen causing annual epidemics and periodic pandemics. CD8+ cytotoxic T lymphocyte (CTL-mediated immunity contributes to clearance of virus-infected cells; CTL immunity targeting the conserved internal proteins of IAVs is a key protection mechanism when neutralizing antibodies are absent during heterosubtypic IAV infection. However, CTL infiltration into the airways, their cytotoxicity, and the effects of produced pro-inflammatory cytokines can cause severe lung tissue injury, thereby contributing to immunopathology. Studies have discovered complicated and exquisite stimulatory and inhibitory mechanisms that regulate CTL magnitude and effector activities during IAV infection. Here, we review the state of knowledge on the roles of IAV-specific CTLs in immune protection and immunopathology during IAV infection in animal models, highlighting the key findings of various requirements and constraints regulating the balance of immune protection and pathology involved in CTL immunity. We also discuss the evidence of cross-reactive CTL immunity as a positive correlate of cross-subtype protection during secondary IAV infection in both animal and human studies. We argue that the effects of CTL immunity on protection and immunopathology depend on multiple layers of host and viral factors, including complex host mechanisms to regulate CTL magnitude and effector activity, the pathogenic nature of the IAV, the innate response milieu, and the host historical immune context of influenza infection. Future efforts are needed to further understand these key host and viral factors, especially to differentiate those that constrain optimally effective CTL anti-viral immunity from those necessary to restrain CTL-mediated nonspecific immunopathology in the various contexts of IAV infection, in order to develop better vaccination and therapeutic strategies for modifying protective CTL immunity.

  9. Inhibitory effect of human telomerase antisense oligodeoxyribonucleotides on the growth of gastric cancer cell lines in variant tumor pathological subtype

    Institute of Scientific and Technical Information of China (English)

    Jing Ye; Yun-Lin Wu; Shu Zhang; Zi Chen; Li-Xia Guo; Ruo-Yu Zhou; Hong Xie

    2005-01-01

    AIM: To investigate the inhibitory effect of specialized human telomerase antisense oligodeoxyribonucleotides on the growth of well (MKN-28), moderately (SGC-7901)and poorly (MKN-45) differentiated gastric cancer cell lines under specific conditions and its inhibition mechanism,and to observe the correlation between the growth inhibition ratio and the tumor pathologic subtype of gastric cancer cells.METHODS: Telomerase activity in three gastric cancer cell lines of variant tumor pathologic subtype was determined by modified TRAP assay before and after the specialized human telomerase antisense oligodeoxyribonucleotides were dealt with under specific conditions. Effect of antisense oligomer under specific conditions of the growth and viability of gastric cancer cell lines was explored by using trypan blue dye exclusion assay, and cell apoptosis was detected by cell morphology observation, flow cytometry and TUNEL assay.RESULTS: Telomerase activity was detected in well,moderately and poorly differentiated gastric cancer cell lines (the quantification expression of telomerase activity was 43.7TPG, 56.5TPG, 76.7TPG, respectively).Telomerase activity was controlled to 30.2TPG, 36.3TPG and 35.2TPG for MKN-28, SGC-7901 and MKN-45 cell lines respectively after treatment with human telomerase antisense oligomers at the concentration of 5 μmol/L, and was entirely inhibited at 10 μmol/L, against the template region of telomerase RNA component, whereas no inhibition effect was detected in missense oligomers (P<0.05). After treatment with antisense oligomers at different concentrations under specific conditions for 96 h, significant growth inhibition effects were found in MKN-45 and SGC-7901gastric cancer cell lines (the inhibition ratio was 40.89%and 71.28%), but not in MKN-28 cell lines (15.86%). The ratio of inactive SGC-7901 cells increased according to the prolongation of treatment from 48 to 96 h. Missense oligomers could not lead to the same effect (P<0

  10. Cell Interactomics and Carcinogenetic Mechanisms

    CERN Document Server

    Baianu, IC; Report to the Institute of Genomics

    2004-01-01

    Single cell interactomics in simpler organisms, as well as somatic cell interactomics in multicellular organisms, involve biomolecular interactions in complex signalling pathways that were recently represented in modular terms by quantum automata with ‘reversible behavior’ representing normal cell cycling and division. Other implications of such quantum automata, modular modeling of signaling pathways and cell differentiation during development are in the fields of neural plasticity and brain development leading to quantum-weave dynamic patterns and specific molecular processes underlying extensive memory, learning, anticipation mechanisms and the emergence of human consciousness during the early brain development in children. Cell interactomics is here represented for the first time as a mixture of ‘classical’ states that determine molecular dynamics subject to Boltzmann statistics and ‘steady-state’, metabolic (multi-stable) manifolds, together with ‘configuration’ spaces of metastable quant...

  11. Physiological and pathological role of local and immigrating colonic stem cells

    Institute of Scientific and Technical Information of China (English)

    Ferenc Sipos; Gábor Valcz; Béla Molnár

    2012-01-01

    The latest avenue of research is revealing the existence of and role for the colonic stem cells in the physiological renewal of the mucosa and in pathological circumstances where they have both positive and negative effects. In the case of human colon, different levels of stem cell compartments exist. First, the crypt epithelial stem cells, which have a role in the normal crypt epithelial cell dynamics and in colorectal carcinogenesis. Close to the crypts, the second layer of stem cells can be found; the local subepithelial stem cell niche, including the pericryptic subepithelial myofibroblasts that regulate the epithelial cell differentiation and have a crucial role in cancer progression and chronic inflammation-related fibrosis. The third level of stem cell compartment is the immigrating bone-marrow-derived stem cells, which have an important role in wound healing after severe mucosal inflammation, but are also involved in cancer invasion. This paper focuses on stem cell biology in the context of physiological and pathological processes in the human colon.

  12. Plasmacytoid Transitional Cell Carcinoma of Bladder: A Clinico-pathological Study and Review of Literatures

    Institute of Scientific and Technical Information of China (English)

    FENG Xiaoli; ZHANG Hongtu; SUN Yuntian; LIU Xiuyun

    2006-01-01

    Objective: To study the pathologic features of plasmacytoid transitional cell carcinoma of the bladder, and to analyze the diagnostic features, criteria for differential diagnosis and the clinical significance of the tumor. Methods: Two cases of bladder plasmacytoid transitional cell carcinoma were studied. Routine paraffin sections with HE staining, Pap smear and immunohistochemistry by S-P method were observed under a light microscope. Pathological and clinical data were analyzed by comparison with early reported cases in literatures. Results: A characteristic feature of this tumor was of deep invasion in the lamina propria and/or muscularis propria, in addition to the component of carcinoma in situ in the mucosa, when tumors were diagnosed. The histological pattern and cytological features showed similarity to a plasmacytoid tumor. The tumor cells were strongly positive for AE1/AE3, CEA and CK18. The prognosis appeared to be worse than ordinary transitional cell carcinoma. Conclusion: The plasmacytoid transitional cell carcinoma of bladder is rare but has typical pathological, immunohistological and clinical features. Pathologists should be aware of this kind of primary tumor of bladder.

  13. CDKN3 expression is negatively associated with pathological tumor stage and CDKN3 inhibition promotes cell survival in hepatocellular carcinoma.

    Science.gov (United States)

    Dai, Wei; Miao, Huilai; Fang, Shuo; Fang, Tao; Chen, Nianping; Li, Mingyi

    2016-08-01

    Aberrant expression of CDKN3 may be involved in carcinogenesis of liver cancer. The effect of CDKN3 on tumorigenesis and the molecular mechanisms involved have not been fully elucidated. Immunohistochemistry was performed to detect CDKN3 expression levels in tumor tissues. CDKN3 siRNA was used to knockdown CDKN3 in QGY7701 hepatocellular carcinoma (HCC) cells. Colony formation assay was used to measure the clonogenic capacity of the tumor cells. Cell viability was determined by MTT assay. Logistic regression was performed to analyze the association between CDKN3 expression level and the HCC clinical pathology index. The CDKN3 expression level was significantly decreased in HCC tumor tissues compared with normal liver tissue and liver cirrhosis tissue. Additionally, CDKN3 expression was negatively‑associated with the pathological stage of the tumor. Inhibition of CKDN3 promoted the clonogenic capacity and chemotherapeutic tolerance in HCC tissues compared with controls. Knockdown of CDKN3 resulted in downregulation of p53 and p21 protein levels, whereas, AKT serine/threonine kinase 1 expression was upregulated. Thus, CDKN3 expression may reduce the survival of tumor cells and alter the sensitivity to therapeutic agents via the AKT/P53/P21 signaling pathway. Therefore, CDKN3 may be involved in tumor differentiation and self-renewal. PMID:27314282

  14. Molecular mechanisms promoting the pathogenesis of Schwann cell neoplasms

    OpenAIRE

    Carroll, Steven L.

    2011-01-01

    Neurofibromas, schwannomas and malignant peripheral nerve sheath tumors (MPNSTs) all arise from the Schwann cell lineage. Despite their common origin, these tumor types have distinct pathologies and clinical behaviors; a growing body of evidence indicates that they also arise via distinct pathogenic mechanisms. Identification of the genes that are mutated in genetic diseases characterized by the development of either neurofibromas and MPNSTs [neurofibromatosis type 1 (NF1)] or schwannomas [ne...

  15. Nuclear Mechanics and Stem Cell Differentiation.

    Science.gov (United States)

    Mao, Xinjian; Gavara, Nuria; Song, Guanbin

    2015-12-01

    Stem cells are characterized by their self-renewal and multi-lineage differentiation potential. Stem cell differentiation is a prerequisite for the application of stem cells in regenerative medicine and clinical therapy. In addition to chemical stimulation, mechanical cues play a significant role in regulating stem cell differentiation. The integrity of mechanical sensors is necessary for the ability of cells to respond to mechanical signals. The nucleus, the largest and stiffest cellular organelle, interacts with the cytoskeleton as a key mediator of cell mechanics. Nuclear mechanics are involved in the complicated interactions of lamins, chromatin and nucleoskeleton-related proteins. Thus, stem cell differentiation is intimately associated with nuclear mechanics due to its indispensable role in mechanotransduction and mechanical response. This paper reviews several main contributions of nuclear mechanics, highlights the hallmarks of the nuclear mechanics of stem cells, and provides insight into the relationship between nuclear mechanics and stem cell differentiation, which may guide clinical applications in the future.

  16. System in biology leading to cell pathology: stable protein-protein interactions after covalent modifications by small molecules or in transgenic cells

    Directory of Open Access Journals (Sweden)

    Malina Halina Z

    2011-01-01

    Full Text Available Abstract Background The physiological processes in the cell are regulated by reversible, electrostatic protein-protein interactions. Apoptosis is such a regulated process, which is critically important in tissue homeostasis and development and leads to complete disintegration of the cell. Pathological apoptosis, a process similar to apoptosis, is associated with aging and infection. The current study shows that pathological apoptosis is a process caused by the covalent interactions between the signaling proteins, and a characteristic of this pathological network is the covalent binding of calmodulin to regulatory sequences. Results Small molecules able to bind covalently to the amino group of lysine, histidine, arginine, or glutamine modify the regulatory sequences of the proteins. The present study analyzed the interaction of calmodulin with the BH3 sequence of Bax, and the calmodulin-binding sequence of myristoylated alanine-rich C-kinase substrate in the presence of xanthurenic acid in primary retinal epithelium cell cultures and murine epithelial fibroblast cell lines transformed with SV40 (wild type [WT], Bid knockout [Bid-/-], and Bax-/-/Bak-/- double knockout [DKO]. Cell death was observed to be associated with the covalent binding of calmodulin, in parallel, to the regulatory sequences of proteins. Xanthurenic acid is known to activate caspase-3 in primary cell cultures, and the results showed that this activation is also observed in WT and Bid-/- cells, but not in DKO cells. However, DKO cells were not protected against death, but high rates of cell death occurred by detachment. Conclusions The results showed that small molecules modify the basic amino acids in the regulatory sequences of proteins leading to covalent interactions between the modified sequences (e.g., calmodulin to calmodulin-binding sites. The formation of these polymers (aggregates leads to an unregulated and, consequently, pathological protein network. The results

  17. Cancer Stem Cells in Primary Liver Cancers: Pathological Concepts and Imaging Findings

    Energy Technology Data Exchange (ETDEWEB)

    Joo, Ijin [Department of Radiology, Seoul National University Hospital, Seoul 110-744 (Korea, Republic of); Kim, Haeryoung [Department of Pathology, Seoul National University Bundang Hospital, Seongnam 463-707 (Korea, Republic of); Lee, Jeong Min [Department of Radiology, Seoul National University Hospital, Seoul 110-744 (Korea, Republic of)

    2015-11-01

    There is accumulating evidence that cancer stem cells (CSCs) play an integral role in the initiation of hepatocarcinogenesis and the maintaining of tumor growth. Liver CSCs derived from hepatic stem/progenitor cells have the potential to differentiate into either hepatocytes or cholangiocytes. Primary liver cancers originating from CSCs constitute a heterogeneous histopathologic spectrum, including hepatocellular carcinoma, combined hepatocellular-cholangiocarcinoma, and intrahepatic cholangiocarcinoma with various radiologic manifestations. In this article, we reviewed the recent concepts of CSCs in the development of primary liver cancers, focusing on their pathological and radiological findings. Awareness of the pathological concepts and imaging findings of primary liver cancers with features of CSCs is critical for accurate diagnosis, prediction of outcome, and appropriate treatment options for patients.

  18. Cancer Stem Cells in Primary Liver Cancers: Pathological Concepts and Imaging Findings

    International Nuclear Information System (INIS)

    There is accumulating evidence that cancer stem cells (CSCs) play an integral role in the initiation of hepatocarcinogenesis and the maintaining of tumor growth. Liver CSCs derived from hepatic stem/progenitor cells have the potential to differentiate into either hepatocytes or cholangiocytes. Primary liver cancers originating from CSCs constitute a heterogeneous histopathologic spectrum, including hepatocellular carcinoma, combined hepatocellular-cholangiocarcinoma, and intrahepatic cholangiocarcinoma with various radiologic manifestations. In this article, we reviewed the recent concepts of CSCs in the development of primary liver cancers, focusing on their pathological and radiological findings. Awareness of the pathological concepts and imaging findings of primary liver cancers with features of CSCs is critical for accurate diagnosis, prediction of outcome, and appropriate treatment options for patients

  19. Development and function of protective and pathologic memory CD4 T cells

    Directory of Open Access Journals (Sweden)

    Megan KL Macleod

    2015-09-01

    Full Text Available IImmunological memory is one of the defining features of the adaptive immune system. As key orchestrators and mediators of immunity, CD4 T cells are central to the vast majority of adaptive immune responses. Generated following an immune response, memory CD4 T cells retain pertinent information about their activation environment enabling them to make rapid effector responses upon reactivation. These responses can either benefit the host by hastening the control of pathogens or cause damaging immunopathology. Here, we will discuss the diversity of the memory CD4 T cell pool, the signals that influence the transition of activated T cells into that pool, and highlight how activation requirements differ between naïve and memory CD4 T cells. A greater understanding of these factors has the potential to aid the design of more effective vaccines and to improve regulation of pathologic CD4 T cells, such as in the context of autoimmunity and allergy.

  20. A46, a Benzothiophene Derived Compound, Suppresses Jak2-Mediated Pathologic Cell Growth

    OpenAIRE

    Majumder, Anurima; Magis, Andrew T.; Park, Sung O.; Figueroa, Nicholas C.; Baskin, Rebekah; Kirabo, Annet; Robert W Allan; Zhao, Zhizhuang Joe; Bisht, Kirpal S.; Keserű, György M.; Sayeski, Peter P.

    2011-01-01

    Hyperkinetic Jak2 tyrosine kinase signaling has been implicated in several hematological disorders including the myeloproliferative neoplasms (MPNs). Effective Jak2 inhibitors can thus have significant therapeutic potential. Here, using structure based virtual screening, we identified a benzothiophene derived Jak2 inhibitor named A46. We hypothesized that this compound would inhibit Jak2-V617F mediated pathologic cell growth. To test this, A46 was analyzed for its ability to i) inhibit recomb...

  1. Blockade of pathological retinal ganglion cell hyperactivity improves optogenetically evoked light responses in rd1 mice

    OpenAIRE

    John Martin Barrett; Patrick Degenaar

    2015-01-01

    Retinitis pigmentosa (RP) is a progressive retinal dystrophy that causes visual impairment and eventual blindness. Retinal prostheses are the best currently available vision-restoring treatment for RP, but only restore crude vision. One possible contributing factor to the poor quality of vision achieved with prosthetic devices is the pathological retinal ganglion cell (RGC) hyperactivity that occurs in photoreceptor dystrophic disorders. Gap junction blockade with meclofenamic acid (MFA) was ...

  2. Pathological factors, behavior, and histological prognostic risk groups in subtypes of penile squamous cell carcinomas (SCC).

    Science.gov (United States)

    Sanchez, Diego F; Soares, Fernando; Alvarado-Cabrero, Isabel; Cañete, Sofía; Fernández-Nestosa, María José; Rodríguez, Ingrid M; Barreto, José; Cubilla, Antonio L

    2015-05-01

    Pathologists' contribution in the determination of prognosis in invasive penile squamous cell carcinoma is crucial. The TNM staging system is based on the identification of pathological data. There are multiple pathologically based factors believed to be important in relation to the rates of regional inguinal lymph node and specific cancer death. Among them are tumor site, size, histological subtypes, thickness or anatomical level of invasion, tumor front, and vascular or perineural invasion. The identification of these factors determines the prognostic profile of patients with penile cancer. These factors are used for the construction of pathological risk groups, prognostic index, or nomograms and are helpful in the prediction of nodal metastasis or patients' outcome. This review will describe in detail the influential pathological prognostic factors present in each tumor category emphasizing the impact of especial histological subtypes in tumor spread and final outcome. There are few studies comprehensibly addressing the relation of tumor morphology and prognosis according to histological types. We are summarizing findings of prognostic factors in 3 different series for the most common types and individual series in more recently described tumor entities. We had found a broad correlation of special subtypes of penile squamous cell carcinomas that made regional nodal status and final outcome predictable according to histological features of the tumor. These findings permitted grouping special subtypes of squamous cell carcinomas into prognosis risk groups of low, intermediate, and high. In the first category of excellent prognoses are the usual grade I, verrucous, papillary NOS, pseudohyperplastic and cuniculatum carcinomas. In the second group, there are the grade II usual, mixed and warty carcinomas. The third category of tumors, with the worst prognosis is composed of high grade usual, basaloid, warty-basaloid, papillary basaloid, and sarcomatoid carcinomas. We

  3. Prognostic implications of cell kinetics, histopathology and pathologic stage in non-Hodgkin's lymphomas.

    Science.gov (United States)

    Silvestrini, R; Costa, A; Giardini, R; Boracchi, P; Del Bino, G; Marubini, E; Rilke, F

    1989-01-01

    Cell kinetics ([3H]-thymidine labelling index, [3H]-Thy LI) were determined on pathologic lymph nodes from 175 untreated adult patients. [3H]-Thy LI significantly differed in low-grade and high-grade malignancy groups according to the Kiel classification (median values, 1.8 per cent and 10.4 per cent, respectively) and in low, intermediate, high grade according to the Working Formulation (median values: 1.7 per cent, 4.8 per cent and 14.2 per cent, respectively) but was unrelated to pathologic stage or patient's age. Cell kinetics, histopathology, pathologic stage and patient's age were significant discriminants of 6-year survival. Multivariate analysis was performed by Cox's proportional hazard model to investigate the role of [3H]-Thy LI after making allowance for the other prognostic factors. When [3H]-Thy LI was added to the model, a large increase (chi square = 29.94) contributed by the cell kinetic variable in identifying patients at different risk was revealed.

  4. Morphological and pathologic changes of experimental chronic atrophic gastritis (CAG) and the regulating mechanism of protein expression in rats

    Institute of Scientific and Technical Information of China (English)

    WANG Liang-jing; CHEN Shu-jie; CHEN Zhe; CAI Jian-ting; SI Jian-min

    2006-01-01

    Objective: To study the pathologic change and molecular regulation in cell proliferation and apoptosis of gastric mucosa in rats with chronic atrophic gastritis (CAG), and evaluate the possible mechanisms. Methods: Rats were administered with 60% alcohol or 2% salicylate sodium, 20 mmol/L deoxycholate sodium and 0.1% ammonia water to establish chronic atrophic gastritis (CAG) models. The gastric specimens were prepared for microscopic view with hematoxylin and eosin (H-E)and alcian blue (A-B) stain. The number of infiltrated inflammatory cells, the thickness of the mucosa gland layer (μm) and the number of gastric glands were calculated. The damage of barrier in mucosa with erosion or ulceration, and the thickness of mucin were examined by scanned electron microscope (SEM). The levels of PGE2, EGF (epiderminal growth factor) and gastrin in the serum were measured with radioimmunoassay or ELISA method. The immunohistochemistry method was used to observe the number of G cells, the expression of protein of EGFR (EGF receptor), C-erbB-2, p53, p16 and bcl-2 in gastric tissue. Results:Under SEM observation, the gastric mucosa was diffused erosion or ulceration and the thickness of mucin was decreased. Compared with normal rats, the grade of inflammatory cell infiltration in CAG rats was elevated, whereas the thickness and number of gastric gland were significantly lower (P<0.05). Compared with normal level of (0.61+0.28) μg/L, EGF in CAG (2.2±0.83) μg/L was significantly higher (P<0.05). The levels of PGE2 and gastrin in serum were significantly lower in CAG rats than that in normal rats (P<0.05). Immunohistochemistry detection showed that the number of G cell in antrum was lower in CAG group (P<0.05). Immuno-stain showed EGFR protein expression in the basal and bilateral membrane, and the cytoplasma in atrophic gastric gland, while negative expression was observed in normal gastric epithelial cells. Positive staining of p53 and p16 protein was localized in

  5. Pathologic bladder microenvironment attenuates smooth muscle differentiation of skin derived precursor cells: implications for tissue regeneration.

    Directory of Open Access Journals (Sweden)

    Cornelia Tolg

    Full Text Available Smooth muscle cell containing organs (bladder, heart, blood vessels are damaged by a variety of pathological conditions necessitating surgery or organ replacement. Currently, regeneration of contractile tissues is hampered by lack of functional smooth muscle cells. Multipotent skin derived progenitor cells (SKPs can easily be isolated from adult skin and can be differentiated in vitro into contractile smooth muscle cells by exposure to FBS. Here we demonstrate an inhibitory effect of a pathologic contractile organ microenvironment on smooth muscle cell differentiation of SKPs. In vivo, urinary bladder strain induces microenvironmental changes leading to de-differentiation of fully differentiated bladder smooth muscle cells. Co-culture of SKPs with organoids isolated from ex vivo stretched bladders or exposure of SKPs to diffusible factors released by stretched bladders (e.g. bFGF suppresses expression of smooth muscle markers (alpha SMactin, calponin, myocardin, myosin heavy chain as demonstrated by qPCR and immunofluorescent staining. Rapamycin, an inhibitor of mTOR signalling, previously observed to prevent bladder strain induced de-differentiation of fully differentiated smooth muscle cells in vitro, inhibits FBS-induced smooth muscle cell differentiation of undifferentiated SKPs. These results suggest that intended precursor cell differentiation may be paradoxically suppressed by the disease context for which regeneration may be required. Organ-specific microenvironment contexts, particularly prevailing disease, may play a significant role in modulating or attenuating an intended stem cell phenotypic fate, possibly explaining the variable and inefficient differentiation of stem cell constructs in in vivo settings. These observations must be considered in drafting any regeneration strategies.

  6. Determinants of pathologic mineralization.

    Science.gov (United States)

    Kirsch, Thorsten

    2008-01-01

    Physiologic mineralization is necessary for the formation of skeletal tissues and for their appropriate functions during adulthood. Mineralization has to be controlled and restricted to specific regions. If the mineralization process occurs in regions that normally do not mineralize, there can be severe consequences (pathologic or ectopic mineralization). Recent findings have indicated that physiologic and pathologic mineralization events are initiated by matrix vesicles, membrane-enclosed particles released from the plasma membranes of mineralization-competent cells. The understanding of how these vesicles are released from the plasma membrane and initiate the mineralization process may provide novel therapeutic strategies to prevent pathologic mineralization. In addition, other regulators (activators and inhibitors) of physiologic mineralization have been identified and characterized, and there is evidence that the same factors also contribute to the regulation of pathologic mineralization. Finally, programmed cell death (apoptosis) may be a contributor to physiologic mineralization and if occurring after tissue injury may induce pathologic mineralization and mineralization-related differentiation events in the injured and surrounding areas. This review describes how the understanding of mechanisms and factors regulating physiologic mineralization can be used to develop new therapeutic strategies to prevent pathologic or ectopic mineralization events.

  7. Cell mechanics in biomedical cavitation

    Science.gov (United States)

    Wang, Qianxi; Manmi, Kawa; Liu, Kuo-Kang

    2015-01-01

    Studies on the deformation behaviours of cellular entities, such as coated microbubbles and liposomes subject to a cavitation flow, become increasingly important for the advancement of ultrasonic imaging and drug delivery. Numerical simulations for bubble dynamics of ultrasound contrast agents based on the boundary integral method are presented in this work. The effects of the encapsulating shell are estimated by adapting Hoff's model used for thin-shell contrast agents. The viscosity effects are estimated by including the normal viscous stress in the boundary condition. In parallel, mechanical models of cell membranes and liposomes as well as state-of-the-art techniques for quantitative measurement of viscoelasticity for a single cell or coated microbubbles are reviewed. The future developments regarding modelling and measurement of the material properties of the cellular entities for cutting-edge biomedical applications are also discussed. PMID:26442142

  8. Alteration of chaperonin60 and pancreatic enzyme in pancreatic acinar cell under pathological condition

    Institute of Scientific and Technical Information of China (English)

    Yong-Yu Li; Moise Bendayan

    2005-01-01

    AIM: To investigate the changes of chaperonin60 (Cpn60)and pancreatic enzymes in pancreatic acinar cells, and to explore their roles in the development of experimental diabetes and acute pancreatitis (AP).METHODS: Two different pathological models were replicated in Sprague-Dawley rats: streptozotocininduced diabetes and sodium deoxycholate-induced AP. The contents of Cpn60 and pancreatic enzymes in different compartments of the acinar cells were measured by quantitative immunocytochemistry.RESULTS: The levels of Cpn60 significantly increased in diabetes, but decreased in AP, especially in the zymogen granules of the pancreatic acinar cells. The elevation of Cpn60 was accompanied with the increased levels of pancreatic lipase and chymotrypsinogen in diabetes.However, a decreased Cpn60 level was accompanied by high levels of lipase and chymotrypsinogen in AP.The amylase level was markedly reduced in both the pathological conditions.CONCLUSION: The equilibrium between Cpn60 and pancreatic enzymes in the acinar cells breaks in AP, and Cpn60 content decreases, suggesting an insufficient chaperone capacity. This may promote the aggregation and autoactivation of the premature enzymes in the pancreatic acinar cells and play roles in the development of AP.

  9. Biopsy-verified bronchiolitis obliterans and other noninfectious lung pathologies after allogeneic hematopoietic stem cell transplantation

    DEFF Research Database (Denmark)

    Uhlving, Hilde Hylland; Andersen, Claus B; Christensen, Ib Jarle;

    2015-01-01

    Bronchiolitis obliterans (BO) is a serious complication of allogeneic hematopoietic stem cell transplantation (HSCT). Lung biopsy is the gold standard for diagnosis. This study describes the course of BO and assesses the congruity between biopsy-verified BO and a modified version of the National...... Institutes of Health's consensus criteria for BO syndrome (BOS) based exclusively on noninvasive measures. We included 44 patients transplanted between 2000 and 2010 who underwent lung biopsy for suspected BO. Of those, 23 were diagnosed with BO and 21 presented other noninfectious pulmonary pathologies......, such as cryptogenic organizing pneumonia, diffuse alveolar damage, interstitial pneumonia, and nonspecific interstitial fibrosis. Compared with patients with other noninfectious pulmonary pathologies, BO patients had significantly lower values of forced expiratory volume in 1 second (FEV1), FEV1/forced vital capacity...

  10. Blimp-1-Dependent IL-10 Production by Tr1 Cells Regulates TNF-Mediated Tissue Pathology

    Science.gov (United States)

    Montes de Oca, Marcela; Kumar, Rajiv; de Labastida Rivera, Fabian; Amante, Fiona H; Sheel, Meru; Faleiro, Rebecca J.; Bunn, Patrick T.; Best, Shannon E.; Beattie, Lynette; Ng, Susanna S.; Edwards, Chelsea L.; Muller, Werner; Cretney, Erika; Nutt, Stephen L.; Smyth, Mark J.; Haque, Ashraful; Hill, Geoffrey R.; Sundar, Shyam; Kallies, Axel; Engwerda, Christian R.

    2016-01-01

    Tumor necrosis factor (TNF) is critical for controlling many intracellular infections, but can also contribute to inflammation. It can promote the destruction of important cell populations and trigger dramatic tissue remodeling following establishment of chronic disease. Therefore, a better understanding of TNF regulation is needed to allow pathogen control without causing or exacerbating disease. IL-10 is an important regulatory cytokine with broad activities, including the suppression of inflammation. IL-10 is produced by different immune cells; however, its regulation and function appears to be cell-specific and context-dependent. Recently, IL-10 produced by Th1 (Tr1) cells was shown to protect host tissues from inflammation induced following infection. Here, we identify a novel pathway of TNF regulation by IL-10 from Tr1 cells during parasitic infection. We report elevated Blimp-1 mRNA levels in CD4+ T cells from visceral leishmaniasis (VL) patients, and demonstrate IL-12 was essential for Blimp-1 expression and Tr1 cell development in experimental VL. Critically, we show Blimp-1-dependent IL-10 production by Tr1 cells prevents tissue damage caused by IFNγ-dependent TNF production. Therefore, we identify Blimp-1-dependent IL-10 produced by Tr1 cells as a key regulator of TNF-mediated pathology and identify Tr1 cells as potential therapeutic tools to control inflammation. PMID:26765224

  11. Coincident expression of the chemokine receptors CCR6 and CCR7 by pathologic Langerhans cells in Langerhans cell histiocytosis.

    Science.gov (United States)

    Fleming, Mark D; Pinkus, Jack L; Fournier, Marcia V; Alexander, Sarah W; Tam, Carmen; Loda, Massimo; Sallan, Stephen E; Nichols, Kim E; Carpentieri, David F; Pinkus, Geraldine S; Rollins, Barrett J

    2003-04-01

    It has been suggested that a switch in chemokine receptor expression underlies Langerhans cell migration from skin to lymphoid tissue. Activated cells are thought to down-regulate CCR6, whose ligand macrophage inflammatory protein-3 alpha (MIP-3 alpha)/CCL20 is expressed in skin, and up-regulate CCR7, whose ligands are in lymphoid tissues. In Langerhans cell histiocytosis (LCH), pathologic Langerhans cells (LCs) accumulate in several tissues, including skin, bone, and lymphoid organs. We have examined 24 LCH cases and find that pathologic LCs expressed CCR6 and CCR7 coincidentally in all cases. Furthermore, MIP-3 alpha/CCL20 is expressed by keratinocytes in involved skin and by macrophages and osteoblasts in involved bone. Expression of CCR6 by pathologic LCs may contribute to their accumulation in nonlymphoid organs such as skin and bone, whereas CCR7 expression may direct them to lymphoid tissue. Histiocytes in Rosai-Dorfman disease and hemophagocytic syndrome also coexpressed CCR6 and CCR7, suggesting that this may be a general attribute of abnormal histiocytes.

  12. Cell mechanics of alveolar epithelial cells (AECs) and macrophages (AMs).

    OpenAIRE

    Féréol, Sophie; Fodil, Redouane; Pelle, Gabriel; Louis, Bruno; Isabey, Daniel

    2008-01-01

    Cell mechanics provides an integrated view of many biological phenomena which are intimately related to cell structure and function. Because breathing constitutes a sustained motion synonymous with life, pulmonary cells are normally designed to support permanent cyclic stretch without breaking, while receiving mechanical cues from their environment. The authors study the mechanical responses of alveolar cells, namely epithelial cells and macrophages, exposed to well-controlled mechanical stre...

  13. Extracellular Membrane Vesicles as Vehicles for Brain Cell-to-Cell Interactions in Physiological as well as Pathological Conditions

    Directory of Open Access Journals (Sweden)

    Gabriella Schiera

    2015-01-01

    Full Text Available Extracellular vesicles are involved in a great variety of physiological events occurring in the nervous system, such as cross talk among neurons and glial cells in synapse development and function, integrated neuronal plasticity, neuronal-glial metabolic exchanges, and synthesis and dynamic renewal of myelin. Many of these EV-mediated processes depend on the exchange of proteins, mRNAs, and noncoding RNAs, including miRNAs, which occurs among glial and neuronal cells. In addition, production and exchange of EVs can be modified under pathological conditions, such as brain cancer and neurodegeneration. Like other cancer cells, brain tumours can use EVs to secrete factors, which allow escaping from immune surveillance, and to transfer molecules into the surrounding cells, thus transforming their phenotype. Moreover, EVs can function as a way to discard material dangerous to cancer cells, such as differentiation-inducing proteins, and even drugs. Intriguingly, EVs seem to be also involved in spreading through the brain of aggregated proteins, such as prions and aggregated tau protein. Finally, EVs can carry useful biomarkers for the early diagnosis of diseases. Herein we summarize possible roles of EVs in brain physiological functions and discuss their involvement in the horizontal spreading, from cell to cell, of both cancer and neurodegenerative pathologies.

  14. Clinical and surgical-pathological staging in early non-small cell lung cancer

    Directory of Open Access Journals (Sweden)

    Ioannis Koukis

    2013-12-01

    Full Text Available Staging is of the utmost importance in the evaluation of a patient with non-small cell lung cancer (NSCLC because it defines the actual extent of the disease. Accurate staging allows multidisciplinary oncology teams to plan the best surgical or medical treatment and to predict patient prognosis. Based on the recommendation of the International Association for the Study of Lung Cancer (IASLC, a tumor, node, and metastases (TNM staging system is currently used for NSCLC. Clinical staging (c-TNM is achieved via non-invasive modalities such as examination of case history, clinical assessment and radiological tests. Pathological staging (p-TNM is based on histological examination of tissue specimens obtained with the aid of invasive techniques, either non-surgical or during the intervention. This review is a critical evaluation of the roles of current pre-operative staging modalities, both invasive and non-invasive. In particular, it focuses on new techniques and their role in providing accurate confirmation of patient TNM status. It also evaluates the surgical-pathological staging modalities used to obtain the true-pathological staging for NSCLC.

  15. Dynamics of the mammalian cell cycle in physiological and pathological conditions.

    Science.gov (United States)

    Gérard, Claude; Goldbeter, Albert

    2016-01-01

    A network of cyclin-dependent kinases (Cdks) controls progression along the successive phases G1, S, G2, and M of the mammalian cell cycle. Deregulations in the expression of molecular components in this network often lead to abusive cell proliferation and cancer. Given the complex nature of the Cdk network, it is fruitful to resort to computational models to grasp its dynamical properties. Investigated by means of bifurcation diagrams, a detailed computational model for the Cdk network shows how the balance between quiescence and proliferation is affected by activators (oncogenes) and inhibitors (tumor suppressors) of cell cycle progression, as well as by growth factors and other external factors such as the extracellular matrix (ECM) and cell contact inhibition. Suprathreshold changes in all these factors can trigger a switch in the dynamical behavior of the network corresponding to a bifurcation between a stable steady state, associated with cell cycle arrest, and sustained oscillations of the various cyclin/Cdk complexes, corresponding to cell proliferation. The model for the Cdk network accounts for the dependence or independence of cell proliferation on serum and/or cell anchorage to the ECM. Such computational approach provides an integrated view of the control of cell proliferation in physiological or pathological conditions. Whether the balance is tilted toward cell cycle arrest or cell proliferation depends on the direction in which the threshold associated with the bifurcation is passed once the cell integrates the multiple signals, internal or external to the Cdk network, that promote or impede progression in the cell cycle. PMID:26613368

  16. Endothelial precursor cell-based therapy to target the pathologic angiogenesis and compensate tumor hypoxia.

    Science.gov (United States)

    Collet, Guillaume; Szade, Krzysztof; Nowak, Witold; Klimkiewicz, Krzysztof; El Hafny-Rahbi, Bouchra; Szczepanek, Karol; Sugiyama, Daisuke; Weglarczyk, Kazimierz; Foucault-Collet, Alexandra; Guichard, Alan; Mazan, Andrzej; Nadim, Mahdi; Fasani, Fabienne; Lamerant-Fayel, Nathalie; Grillon, Catherine; Petoud, Stéphane; Beloeil, Jean-Claude; Jozkowicz, Alicja; Dulak, Jozef; Kieda, Claudine

    2016-01-28

    Hypoxia-inducing pathologies as cancer develop pathologic and inefficient angiogenesis which rules tumor facilitating microenvironment, a key target for therapy. As such, the putative ability of endothelial precursor cells (EPCs) to specifically home to hypoxic sites of neovascularization prompted to design optimized, site-specific, cell-mediated, drug-/gene-targeting approach. Thus, EPC lines were established from aorta-gonad-mesonephros (AGM) of murine 10.5 dpc and 11.5 dpc embryo when endothelial repertoire is completed. Lines representing early endothelial differentiation steps were selected: MAgEC10.5 and MagEC11.5. Distinct in maturation, they differently express VEGF receptors, VE-cadherin and chemokine/receptors. MAgEC11.5, more differentiated than MAgEC 10.5, displayed faster angiogenesis in vitro, different response to hypoxia and chemokines. Both MAgEC lines cooperated to tube-like formation with mature endothelial cells and invaded tumor spheroids through a vasculogenesis-like process. In vivo, both MAgEC-formed vessels established blood flow. Intravenously injected, both MAgECs invaded Matrigel(TM)-plugs and targeted tumors. Here we show that EPCs (MAgEC11.5) target tumor angiogenesis and allow local overexpression of hypoxia-driven soluble VEGF-receptor2 enabling drastic tumor growth reduction. We propose that such EPCs, able to target tumor angiogenesis, could act as therapeutic gene vehicles to inhibit tumor growth by vessel normalization resulting from tumor hypoxia alleviation. PMID:26577811

  17. Acinar Cell Cyst adenoma (Acinar Cystic Transformation) of the Pancreas: the Radiologic-Pathologic Features

    Energy Technology Data Exchange (ETDEWEB)

    Gumus, Mehmet; Algin, Oktay; Gundogdu, Haldun [Ataturk Training and Research Hospital, Ankara (Turkmenistan); Ugras, Serdar [Selcuk University, Selcuklu Medical Faculty, Konya (Turkmenistan)

    2011-02-15

    Acinar cystic transformation of the pancreas is also known as acinar cell cystadenoma (ACC), and this is an extremely rare benign lesion that was first described in April 2002. We report here on a case of a previously asymptomatic patient with pancreatic ACC and this was diagnosed by computed tomography (CT) and magnetic resonance imaging (MRI). To the best of our knowledge, there is no previous report concerning the CT or MRI features of ACC in the medical literature. We present here the CT, MRI and pathological findings of pancreatic ACC

  18. Bioluminescence imaging of β cells and intrahepatic insulin gene activity under normal and pathological conditions.

    Directory of Open Access Journals (Sweden)

    Tokio Katsumata

    Full Text Available In diabetes research, bioluminescence imaging (BLI has been applied in studies of β-cell impairment, development, and islet transplantation. To develop a mouse model that enables noninvasive imaging of β cells, we generated a bacterial artificial chromosome (BAC transgenic mouse in which a mouse 200-kbp genomic fragment comprising the insulin I gene drives luciferase expression (Ins1-luc BAC transgenic mouse. BLI of mice was performed using the IVIS Spectrum system after intraperitoneal injection of luciferin, and the bioluminescence signal from the pancreatic region analyzed. When compared with MIP-Luc-VU mice [FVB/N-Tg(Ins1-lucVUPwrs/J] expressing luciferase under the control of the 9.2-kbp mouse insulin I promoter (MIP, the bioluminescence emission from Ins1-luc BAC transgenic mice was enhanced approximately 4-fold. Streptozotocin-treated Ins1-luc BAC transgenic mice developed severe diabetes concomitant with a sharp decline in the BLI signal intensity in the pancreas. Conversely, mice fed a high-fat diet for 8 weeks showed an increase in the signal, reflecting a decrease or increase in the β-cell mass. Although the bioluminescence intensity of the islets correlated well with the number of isolated islets in vitro, the intensity obtained from a living mouse in vivo did not necessarily reflect an absolute quantification of the β-cell mass under pathological conditions. On the other hand, adenovirus-mediated gene transduction of β-cell-related transcription factors in Ins1-luc BAC transgenic mice generated luminescence from the hepatic region for more than 1 week. These results demonstrate that BLI in Ins1-luc BAC transgenic mice provides a noninvasive method of imaging islet β cells and extrapancreatic activity of the insulin gene in the liver under normal and pathological conditions.

  19. Evidence from Human and Animal Studies: Pathological Roles of CD8+ T Cells in Autoimmune Peripheral Neuropathies

    Science.gov (United States)

    Yang, Mu; Peyret, Corentin; Shi, Xiang Qun; Siron, Nicolas; Jang, Jeong Ho; Wu, Sonia; Fournier, Sylvie; Zhang, Ji

    2015-01-01

    Autoimmune peripheral neuropathies such as Guillain-Barre Syndrome (GBS) and chronic inflammatory demyelinating polyneuropathy (CIDP) affect millions of people worldwide. Despite significant advances in understanding the pathology, the molecular and cellular mechanisms of immune-mediated neuropathies remain elusive. T lymphocytes definitely play an important role in disease pathogenesis and CD4+ T cells have been the main area of research for decades. This is partly due to the fact that the most frequent animal model to study autoimmune peripheral neuropathy is experimental allergic neuritis (EAN). As it is induced commonly by immunization with peripheral nerve proteins, EAN is driven mainly by CD4+ T cells. However, similarly to what has been reported for patients suffering from multiple sclerosis, a significant body of evidence indicates that CD8+ T cells may play a pathogenic role in GBS and CIDP disease development and/or progression. Here, we summarize clinical studies pertaining to the presence and potential role of CD8+ T cells in autoimmune peripheral neuropathies. We also discuss the findings from our most recent studies using a transgenic mouse line (L31 mice) in which the T cell co-stimulator molecule B7.2 (CD86) is constitutively expressed in antigen presenting cells of the nervous tissues. L31 mice spontaneously develop peripheral neuropathy, and CD8+ T cells are found accumulating in peripheral nerves of symptomatic animals. Interestingly, depletion of CD4+ T cells accelerates disease onset and increases disease prevalence. Finally, we point out some unanswered questions for future research to dissect the critical roles of CD8+ T cells in autoimmune peripheral neuropathies. PMID:26528293

  20. Evidence from human and animal studies: Pathological roles of CD8+ T cells in autoimmune peripheral neuropathies

    Directory of Open Access Journals (Sweden)

    Mu eYang

    2015-10-01

    Full Text Available Autoimmune peripheral neuropathies such as Guillain Barre Syndrome (GBS and chronic inflammatory demyelinating polyneuropathy (CIDP affect millions of people worldwide. Despite significant advances in understanding the pathology, the molecular and cellular mechanisms of immune-mediated neuropathies remain elusive. T lymphocytes definitely play an important role in disease pathogenesis and CD4+ T cells have been the main area of research for decades. This is partly due to the fact that the most frequent animal model to study autoimmune peripheral neuropathy is experimental allergic neuritis (EAN. As it is induced commonly by immunization with peripheral nerve proteins, EAN is driven mainly by CD4+ T cells. However, similarly to what has been reported for patients suffering from multiple sclerosis, a significant body of evidence indicate that CD8+ T cells may play a pathogenic role in GBS and CIDP disease development and/or progression. Here, we summarize clinical studies pertaining to the presence and potential role of CD8+ T cells in autoimmune peripheral neuropathy. We also discuss the findings from our most recent studies using a transgenic mouse line (L31 mice in which the T cell co-stimulator molecule B7.2 (CD86 is constitutively expressed in antigen presenting cells of the nervous tissues. L31 mice spontaneously develop peripheral neuropathy, and CD8+ T cells are found accumulating in peripheral nerves of symptomatic animals. Interestingly, depletion of CD4+ T cells accelerates disease onset and increases disease prevalence. Finally, we point out some unanswered questions for future research to dissect the critical roles of CD8+ T cells in autoimmune peripheral neuropathies.

  1. Alzheimer's Disease: Mechanism and Approach to Cell Therapy.

    Science.gov (United States)

    Amemori, Takashi; Jendelova, Pavla; Ruzicka, Jiri; Urdzikova, Lucia Machova; Sykova, Eva

    2015-11-04

    Alzheimer's disease (AD) is the most common form of dementia. The risk of AD increases with age. Although two of the main pathological features of AD, amyloid plaques and neurofibrillary tangles, were already recognized by Alois Alzheimer at the beginning of the 20th century, the pathogenesis of the disease remains unsettled. Therapeutic approaches targeting plaques or tangles have not yet resulted in satisfactory improvements in AD treatment. This may, in part, be due to early-onset and late-onset AD pathogenesis being underpinned by different mechanisms. Most animal models of AD are generated from gene mutations involved in early onset familial AD, accounting for only 1% of all cases, which may consequently complicate our understanding of AD mechanisms. In this article, the authors discuss the pathogenesis of AD according to the two main neuropathologies, including senescence-related mechanisms and possible treatments using stem cells, namely mesenchymal and neural stem cells.

  2. Ouabain at pathological concentrations might induce damage in human vascular endothelial cells

    Institute of Scientific and Technical Information of China (English)

    Yan-ping REN; Ruo-wen HUANG; Zhuo-ren L(U)

    2006-01-01

    Aim: To examine the time- and dose-dependent effects of ouabain on human umbilical vein endothelial cells (HUVEC) in vivo, and the changes in aortic endothelium and the different expression levels of Kv4.2 in vitro. Methods: The proliferation of HUVEC and cell death were determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay, the incorporation of [3H]TdR,trypan blue staining, and lactate dehydrogenase (LDH) release. The response of endothelial cells to ouabain was explored with a complementary DNA microarray and a candidate gene was found. "Ouabain-sensitive" hypertensive rats were established by chronic administration of ouabain. Changes in the aortic endothelium were observed by electron microscopy, and the expression level of Ky4.2 in different animals was studied by using real-time quantitative reverse transcription-polymerase chain reaction (RT-PCR). Results: Ouabain stimulated the proliferation of HUVEC at physiological concentrations (0.3-0.9 nmol/L). Ouabain at pathological concentrations (0.9-1.8 nmol/L) inhibited proliferation and induced cell death, mRNA profile analysis indicated that 340 genes were differentially expressed after ouabain treatment: 145 were upregulated, of which 6 were upregulated significantly, including KCND2 (encoding the potassium voltagegated channel shal-related subfamily member 2). The upregulated genes were mainly related to cell metabolism and transcription. In ouabain-sensitive hypertensive rats, the aortic endothelium was damaged and Kv4.2 (coded by KCND2)was over-expressed. Conclusion: The physiological role of ouabain in HUVEC might involve the control of growth and metabolism. Ouabain at pathological concentrations might affect the structure and function of the vascular endothelium by modification of expression of the KCND2 gene, and participate vascular remodeling in hypertension.

  3. LABILE IRON IN CELLS AND BODY FLUIDS . Physiology, Pathology and Pharmacology

    Directory of Open Access Journals (Sweden)

    Zvi Ioav Cabantchik

    2014-03-01

    Full Text Available In living systems iron appears predominantly associated with proteins, but can also be detected in forms referred as labile iron, which denotes the combined redox properties of iron and its amenability to exchange between ligands, including chelators. The labile cell iron (LCI composition varies with metal concentration and substances with chelating groups but also with pH and the redox potential. Although physiologically in the lower µM range, LCI plays a key role in cell iron economy as cross-roads of metabolic pathways. LCI levels are continually regulated by an iron-responsive machinery that balances iron uptake versus deposition into ferritin. However, LCI rises aberrantly in some cell types due to faulty cell utilization pathways or infiltration by pathological iron forms that are found in hemosiderotic plasma. As LCI attains pathological levels, it can catalyze reactive O species (ROS formation that, at particular threshold, can surpass cellular anti-oxidant capacities and seriously damage its constituents. While in normal plasma and interstitial fluids, virtually all iron is securely carried by circulating transferrin (that renders iron essentially non-labile, in systemic iron overload (IO, the total plasma iron binding capacity is often surpassed by a massive iron influx from hyperabsorptive gut or from erythrocyte overburdened spleen and/or liver. As plasma transferrin approaches iron saturation, labile plasma iron (LPI emerges in forms that can infiltrate cells by unregulated routes and raise LCI to toxic levels. Despite the limited knowledge available on LPI speciation in different types and degrees of iron overload, LPI measurements can be and are in fact used for identifying systemic IO and for initiating/adjusting chelation regimens to attain full-day LPI protection. A recent application of labile iron assay is the detection of labile components in iv iron formulations per se as well as in plasma (LPI following parenteral iron

  4. Small cell neuroendocrine tumour of the endometrium and the importance of pathologic diagnosis.

    Science.gov (United States)

    Estruch, Adriana; Minig, Lucas; Illueca, Carmen; Romero, Ignacio; Guinot, Jose Luis; Poveda, Andrés

    2016-01-01

    Small cell carcinoma of the endometrium is a very rare entity. They are very aggressive tumours, with a poor prognosis. They represent a clinical challenge because of a lack of a standardised treatment. We see here a case of a 67-year-old woman with a history of a lobular breast carcinoma, diagnosed in 2002. After presenting with postmenopausal vaginal bleeding in October 2014, she underwent a hysteroscopy-guided biopsy which revealed a metastasis of breast carcinoma. A hysterectomy and bilateral oophorectomy was performed because of uncontrolled uterine bleeding. The pathologic diagnosis was small cell carcinoma (SCC) of the endometrium. A surgical complete cytoreduction was achieved after the case being presented in a multidisciplinary tumour board. Pathologic results revealed metastasis from peritoneal implants of SCC on the endometrium, and metastasis in pelvic and para-aortic lymph nodes from serous carcinoma of the endometrium. A total of four cycles of adjuvant chemotherapy based on cisplatin (80mg/m² day one) and etoposide (100mg/m² day one, two, three) every 21 days was given. The patient experienced persistent disease and died 17 months after the diagnosis. SCC of the endometrium is a very rare and aggressive disease that requires an individualised multidisciplinary management. PMID:27610194

  5. Molecular Mechanisms of Glutamine Synthetase Mutations that Lead to Clinically Relevant Pathologies.

    Science.gov (United States)

    Frieg, Benedikt; Görg, Boris; Homeyer, Nadine; Keitel, Verena; Häussinger, Dieter; Gohlke, Holger

    2016-02-01

    Glutamine synthetase (GS) catalyzes ATP-dependent ligation of ammonia and glutamate to glutamine. Two mutations of human GS (R324C and R341C) were connected to congenital glutamine deficiency with severe brain malformations resulting in neonatal death. Another GS mutation (R324S) was identified in a neurologically compromised patient. However, the molecular mechanisms underlying the impairment of GS activity by these mutations have remained elusive. Molecular dynamics simulations, free energy calculations, and rigidity analyses suggest that all three mutations influence the first step of GS catalytic cycle. The R324S and R324C mutations deteriorate GS catalytic activity due to loss of direct interactions with ATP. As to R324S, indirect, water-mediated interactions reduce this effect, which may explain the suggested higher GS residual activity. The R341C mutation weakens ATP binding by destabilizing the interacting residue R340 in the apo state of GS. Additionally, the mutation is predicted to result in a significant destabilization of helix H8, which should negatively affect glutamate binding. This prediction was tested in HEK293 cells overexpressing GS by dot-blot analysis: Structural stability of H8 was impaired through mutation of amino acids interacting with R341, as indicated by a loss of masking of an epitope in the glutamate binding pocket for a monoclonal anti-GS antibody by L-methionine-S-sulfoximine; in contrast, cells transfected with wild type GS showed the masking. Our analyses reveal complex molecular effects underlying impaired GS catalytic activity in three clinically relevant mutants. Our findings could stimulate the development of ATP binding-enhancing molecules by which the R324S mutant can be repaired extrinsically.

  6. Molecular Mechanisms of Glutamine Synthetase Mutations that Lead to Clinically Relevant Pathologies.

    Directory of Open Access Journals (Sweden)

    Benedikt Frieg

    2016-02-01

    Full Text Available Glutamine synthetase (GS catalyzes ATP-dependent ligation of ammonia and glutamate to glutamine. Two mutations of human GS (R324C and R341C were connected to congenital glutamine deficiency with severe brain malformations resulting in neonatal death. Another GS mutation (R324S was identified in a neurologically compromised patient. However, the molecular mechanisms underlying the impairment of GS activity by these mutations have remained elusive. Molecular dynamics simulations, free energy calculations, and rigidity analyses suggest that all three mutations influence the first step of GS catalytic cycle. The R324S and R324C mutations deteriorate GS catalytic activity due to loss of direct interactions with ATP. As to R324S, indirect, water-mediated interactions reduce this effect, which may explain the suggested higher GS residual activity. The R341C mutation weakens ATP binding by destabilizing the interacting residue R340 in the apo state of GS. Additionally, the mutation is predicted to result in a significant destabilization of helix H8, which should negatively affect glutamate binding. This prediction was tested in HEK293 cells overexpressing GS by dot-blot analysis: Structural stability of H8 was impaired through mutation of amino acids interacting with R341, as indicated by a loss of masking of an epitope in the glutamate binding pocket for a monoclonal anti-GS antibody by L-methionine-S-sulfoximine; in contrast, cells transfected with wild type GS showed the masking. Our analyses reveal complex molecular effects underlying impaired GS catalytic activity in three clinically relevant mutants. Our findings could stimulate the development of ATP binding-enhancing molecules by which the R324S mutant can be repaired extrinsically.

  7. Correlation between apparent diffusion coefficient value and pathological grading in pT1b clear cell renal cell carcinoma

    International Nuclear Information System (INIS)

    Objective: To evaluate the correlation of ADC values on 3.0 T MR with the pathological grades in pT1b clear cell renal cell carcinoma (CCRCC). Methods: Conventional MR images, ADC values and Fuhrman pathological grading of pT1b CCRCC were performed in 30 patients. Grade Ⅰ and Ⅱ were defined as low-grade group; grade Ⅲ and Ⅳ were defined as high-grade group. The differences of ADC values among four different pathologic grades were compared with a one-way analysis of variance. The comparison of ADC values of two different grade groups was performed with t test, and the ROC curve was performed to evaluate the diagnostic efficacy of ADC value. Correlation between pathological grading and ADC values was assessed with Spearman rank correlation analysis. Results: (1) The mean ADC value of grading Ⅰ (10 patients), Ⅱ (8 patients), Ⅲ (7 patients), Ⅳ (5 patients) was (0.94 ± 0.11) ×10-3 mm2/s, (0.82 ±0.13) × 10-3 mm2/s,(0.68 ±0.09) × 10-3 mm2/s, (0.59 ±0.03) × 10-3 mm2/s, respectively. Significant differences of ADC values among the four grades were present (F=16.422, P=0.000). (2) The mean ADC value of the low-grade group was significantly higher than that of the high-grade group (t=5.738, P=0.000). Sensitivity and specificity of diagnosing the low-grade group was 88.9% and 83.3% respectively. There was a negative correlation between pathological grading and ADC value (r=-0.807, P<0.05). Conclusions: The ADC values of pT1b CCRCC have close correlation with pathological grading. They can be used to predict the degree of tumor malignancy preoperatively and guide surgical planning. (authors)

  8. Glioma grading using cell nuclei morphologic features in digital pathology images

    Science.gov (United States)

    Reza, Syed M. S.; Iftekharuddin, Khan M.

    2016-03-01

    This work proposes a computationally efficient cell nuclei morphologic feature analysis technique to characterize the brain gliomas in tissue slide images. In this work, our contributions are two-fold: 1) obtain an optimized cell nuclei segmentation method based on the pros and cons of the existing techniques in literature, 2) extract representative features by k-mean clustering of nuclei morphologic features to include area, perimeter, eccentricity, and major axis length. This clustering based representative feature extraction avoids shortcomings of extensive tile [1] [2] and nuclear score [3] based methods for brain glioma grading in pathology images. Multilayer perceptron (MLP) is used to classify extracted features into two tumor types: glioblastoma multiforme (GBM) and low grade glioma (LGG). Quantitative scores such as precision, recall, and accuracy are obtained using 66 clinical patients' images from The Cancer Genome Atlas (TCGA) [4] dataset. On an average ~94% accuracy from 10 fold crossvalidation confirms the efficacy of the proposed method.

  9. Mechanical communication in cardiac cell synchronized beating

    Science.gov (United States)

    Nitsan, Ido; Drori, Stavit; Lewis, Yair E.; Cohen, Shlomi; Tzlil, Shelly

    2016-05-01

    Cell-cell communication, which enables cells to coordinate their activity and is essential for growth, development and function, is usually ascribed a chemical or electrical origin. However, cells can exert forces and respond to environment elasticity and to mechanical deformations created by their neighbours. The extent to which this mechanosensing ability facilitates intercellular communication remains unclear. Here we demonstrate mechanical communication between cells directly for the first time, providing evidence for a long-range interaction that induces long-lasting alterations in interacting cells. We show that an isolated cardiac cell can be trained to beat at a given frequency by mechanically stimulating the underlying substrate. Deformations are induced using an oscillatory mechanical probe that mimics the deformations generated by a beating neighbouring cardiac cell. Unlike electrical field stimulation, the probe-induced beating rate is maintained by the cell for an hour after the stimulation stops, implying that long-term modifications occur within the cell. These long-term alterations provide a mechanism for cells that communicate mechanically to be less variable in their electromechanical delay. Mechanical coupling between cells therefore ensures that the final outcome of action potential pacing is synchronized beating. We further show that the contractile machinery is essential for mechanical communication.

  10. Molecular Mechanisms of Cell-cell Recognition

    Institute of Scientific and Technical Information of China (English)

    WANG Jia-Huai

    2004-01-01

    Cell-cell recognition is the key for multicellular organisms to survive. This recognition critically depends on protein-protein interactions from opposing cell surfaces. Recent structural investigations reveal unique features of these cell surface receptors and how they interact. These interactions are specific, but usually relatively weak, with more hydrophilic forces involved in binding. The receptors appear to have specialized ways to present their key interacting elements for ligand-binding from the cell surface. Cell-cell contacts are multivalent. A large group of cell surface molecules are engaged in interactions. Characteristic weak interactions make possible for each individual molecule pair within the group to constantly associate-dissociate-reassociate, such that the cell-cell recognition becomes a dynamic process. The immunological synapse is a good example for immune receptors to be orchestrated in performing immunological function in a collective fashion.

  11. Columnar cell lesions of the canine mammary gland: pathological features and immunophenotypic analysis

    Directory of Open Access Journals (Sweden)

    Cassali Geovanni D

    2010-02-01

    Full Text Available Abstract Background It has been suggested that columnar cell lesions indicate an alteration of the human mammary gland involved in the development of breast cancer. They have not previously been described in canine mammary gland. The aim of this paper is describe the morphologic spectrum of columnar cell lesions in canine mammary gland specimens and their association with other breast lesions. Methods A total of 126 lesions were subjected to a comprehensive morphological review based upon the human breast classification system for columnar cell lesions. The presence of preinvasive (epithelial hyperplasia and in situ carcinoma and invasive lesions was determined and immunophenotypic analysis (estrogen receptor (ER, progesterone receptor (PgR, high molecular weight cytokeratin (34βE-12, E-cadherin, Ki-67, HER-2 and P53 was perfomed. Results Columnar cell lesions were identified in 67 (53.1% of the 126 canine mammary glands with intraepithelial alterations. They were observed in the terminal duct lobular units and characterized at dilated acini may be lined by several layers of columnar epithelial cells with elongated nuclei. Of the columnar cell lesions identified, 41 (61.2% were without and 26 (38.8% with atypia. Association with ductal hyperplasia was observed in 45/67 (67.1%. Sixty (89.5% of the columnar cell lesions coexisted with neoplastic lesions (20 in situ carcinomas, 19 invasive carcinomas and 21 benign tumors. The columnar cells were ER, PgR and E-cadherin positive but negative for cytokeratin 34βE-12, HER-2 and P53. The proliferation rate as measured by Ki-67 appeared higher in the lesions analyzed than in normal TDLUs. Conclusions Columnar cell lesions in canine mammary gland are pathologically and immunophenotypically similar to those in human breast. This may suggest that dogs are a suitable model for the comparative study of noninvasive breast lesions.

  12. Cell mechanics as a marker for diseases: Biomedical applications of AFM

    Science.gov (United States)

    Rianna, Carmela; Radmacher, Manfred

    2016-08-01

    Many diseases are related to changes in cell mechanics. Atomic Force Microscopy (AFM) is one of the most suitable techniques allowing the investigation of both topography and mechanical properties of adherent cells with high spatial resolution under physiological conditions. Over the years the use of this technique in medical and clinical applications has largely increased, resulting in the notion of cell mechanics as a biomarker to discriminate between different physiological and pathological states of cells. Cell mechanics has proven to be a biophysical fingerprint able discerning between cell phenotypes, unraveling processes in aging or diseases, or even detecting and diagnosing cellular pathologies. We will review in this report some of the works on cell mechanics investigated by AFM with clinical and medical relevance in order to clarify the state of research in this field and to highlight the role of cell mechanics in the study of pathologies, focusing on cancer, blood and cardiovascular diseases. At the request of all authors of the paper, and with the agreement of the Proceedings Editor, an updated version of this article was published on 26 September 2016. The original version supplied to AIP Publishing contained blurred figures introduced during the PDF conversion process. Moreover, Equations (5), (6), and (7) were not correctly cited in the text. These errors have been corrected in the updated and republished article.

  13. Central nervous system lesions in adult T-cell leukaemia: MRI and pathology

    Energy Technology Data Exchange (ETDEWEB)

    Kitajima, M.; Korogi, Y.; Shigematsu, Y.; Liang, L.; Takahashi, M. [Department of Radiology, Kumamoto University School of Medicine, Honjo, Kumamoto (Japan); Matsuoka, M. [Second Division of Internal Medicine, Kumamoto University School of Medicine, Honjo, Kumamoto (Japan); Yamamoto, T. [Department of Pathology, Kumamoto University School of Medicine, Honjo, Kumamoto (Japan); Jhono, M. [Department of Dermatology, Kumamoto University School of Medicine, Honjo, Kumamoto (Japan); Eto, K. [The National Institute for Minamata Disease, Minamata (Japan)

    2002-07-01

    Adult T-cell leukaemia (ATL) is a T-cell lymphoid neoplasm caused by human T-cell leukaemia virus type I (HTLV-I). Radiological findings in central nervous system (CNS) involvement have not been well characterised. We reviewed the MRI of 18 patients with ATL who developed new neurological symptoms or signs, and pathology specimens from a 53-year-old woman who died of ATL. MRI findings were divided into three categories: definite, probable, and other abnormal. Definite and probable findings were defined as ATL-related. The characteristic findings were multiple parenchymal masses with or without contrast enhancement adjacent to cerebrospinal fluid (CSF) spaced and the deep grey matter of both cerebral hemispheres, plus leptomeningeal lesion. One patient had both cerebral and spinal cord lesions. Other abnormal findings in eight patients included one case of leukoencephalopathy caused by methotrexate. The histology findings consisted of clusters of tumour cells along perivascular spaces, and scattered infiltration of the parenchyma, with nests of tumour cells. Leptomeningeal infiltration by tumour spread into the parenchyma and secondary degeneration of the neuronal tracts was observed. MRI was useful for detecting CNS invasion by ATL and differentiating it from other abnormalities. The MRI findings seemed to correlate well with the histological changes. (orig.)

  14. Key Physical Mechanisms in Nanostructured Solar Cells

    Energy Technology Data Exchange (ETDEWEB)

    Dr Stephan Bremner

    2010-07-21

    The objective of the project was to study both theoretically and experimentally the excitation, recombination and transport properties required for nanostructured solar cells to deliver energy conversion efficiencies well in excess of conventional limits. These objectives were met by concentrating on three key areas, namely, investigation of physical mechanisms present in nanostructured solar cells, characterization of loss mechanisms in nanostructured solar cells and determining the properties required of nanostructured solar cells in order to achieve high efficiency and the design implications.

  15. Uphill running improves rat Achilles tendon tissue mechanical properties and alters gene expression without inducing pathological changes

    DEFF Research Database (Denmark)

    Heinemeier, K M; Skovgaard, D; Bayer, M L;

    2012-01-01

    a previously proposed rat model for Achilles tendon overuse. Ten adult male Sprague-Dawley rats ran on a treadmill with 10° incline, 1 h/day, 5 days/wk (17-20 m/min) for 12 wk and were compared with 12 control rats. Histological, mechanical, and gene-expression changes were measured on the Achilles tendons...... after the intervention, and local tendon glucose-uptake was measured before and after the intervention with positron emission tomography. No differences were detected between runners and controls in tissue histology or in glucose uptake, indicating that tendon pathology was not induced. Greater tendon...

  16. Active cell mechanics: Measurement and theory.

    Science.gov (United States)

    Ahmed, Wylie W; Fodor, Étienne; Betz, Timo

    2015-11-01

    Living cells are active mechanical systems that are able to generate forces. Their structure and shape are primarily determined by biopolymer filaments and molecular motors that form the cytoskeleton. Active force generation requires constant consumption of energy to maintain the nonequilibrium activity to drive organization and transport processes necessary for their function. To understand this activity it is necessary to develop new approaches to probe the underlying physical processes. Active cell mechanics incorporates active molecular-scale force generation into the traditional framework of mechanics of materials. This review highlights recent experimental and theoretical developments towards understanding active cell mechanics. We focus primarily on intracellular mechanical measurements and theoretical advances utilizing the Langevin framework. These developing approaches allow a quantitative understanding of nonequilibrium mechanical activity in living cells. This article is part of a Special Issue entitled: Mechanobiology.

  17. Molecular biological mechanism II. Molecular mechanisms of cell cycle regulation

    International Nuclear Information System (INIS)

    The cell cycle in eukaryotes is regulated by central cell cycle controlling protein kinase complexes. These protein kinase complexes consist of a catalytic subunit from the cyclin-dependent protein kinase family (CDK), and a regulatory subunit from the cyclin family. Cyclins are characterised by their periodic cell cycle related synthesis and destruction. Each cell cycle phase is characterised by a specific set of CDKs and cyclins. The activity of CDK/cyclin complexes is mainly regulated on four levels. It is controlled by specific phosphorylation steps, the synthesis and destruction of cyclins, the binding of specific inhibitor proteins, and by active control of their intracellular localisation. At several critical points within the cell cycle, named checkpoints, the integrity of the cellular genome is monitored. If damage to the genome or an unfinished prior cell cycle phase is detected, the cell cycle progression is stopped. These cell cycle blocks are of great importance to secure survival of cells. Their primary importance is to prevent the manifestation and heritable passage of a mutated genome to daughter cells. Damage sensing, DNA repair, cell cycle control and apoptosis are closely linked cellular defence mechanisms to secure genome integrity. Disregulation in one of these defence mechanisms are potentially correlated with an increased cancer risk and therefore in at least some cases with an increased radiation sensitivity. (orig.)

  18. Adrenomedullin promotes differentiation of oligodendrocyte precursor cells into myelin-basic-protein expressing oligodendrocytes under pathological conditions in vitro

    OpenAIRE

    Takakuni Maki; Yoko Takahashi; Nobukazu Miyamoto; Liang, Anna C.; Masafumi Ihara; Eng H Lo; Ken Arai

    2015-01-01

    Oligodendrocytes, which are the main cell type in cerebral white matter, are generated from their precursor cells (oligodendrocyte precursor cells: OPCs). However, the differentiation from OPCs to oligodendrocytes is disturbed under stressed conditions. Therefore, drugs that can improve oligodendrocyte regeneration may be effective for white matter-related diseases. Here we show that a vasoactive peptide adrenomedullin (AM) promotes the in vitro differentiation of OPCs under pathological cond...

  19. Electrodeformation for single cell mechanical characterization

    Science.gov (United States)

    Chen, Jian; Abdelgawad, Mohamed; Yu, Liming; Shakiba, Nika; Chien, Wei-Yin; Lu, Zhe; Geddie, William R.; Jewett, Michael A. S.; Sun, Yu

    2011-05-01

    This paper presents the use of electrodeformation as a method for single cell mechanical characterization in which mechanical properties of SiHa and ME180 cells (two cervical cancer cell lines) were quantified. Cells were directly placed between two microelectrodes with a rectangular ac electric field applied, and cell deformation was recorded under certain experimental conditions. Numerical simulations were performed to model cell electrodeformation based on the Maxwell stress tensor formulation. In these simulations, effects of cell electrical property variations on their electrodeformed behavior were investigated. By comparing the measured morphological changes with those obtained from numerical simulations, we were able to quantify Young's modulus of SiHa cells (601 ± 183 Pa) and ME180 cells (1463 ± 649 Pa). These values were consistent with Young's modulus values (SiHa: 400 ± 290 Pa and ME180: 1070 ± 580 Pa) obtained from conventional micropipette aspiration.

  20. Fluorescence imaging to localize head and neck squamous cell carcinoma for enhanced pathological assessment.

    Science.gov (United States)

    Warram, Jason M; de Boer, Esther; van Dam, Gooitzen M; Moore, Lindsay S; Bevans, Stephanie L; Walsh, Erika M; Young, Erik S; Carroll, William R; Stevens, Todd M; Rosenthal, Eben L

    2016-04-01

    Accurately identifying close or positive margins in real-time permits re-excision during surgical procedures. Intraoperative assessment of margins via gross examination and frozen section is a widely used tool to assist the surgeon in achieving complete resection. While this methodology permits diagnosis of freshly resected tissue, the process is fraught with misinterpretation and sampling errors. During fluorescence-guided surgery, an exogenous fluorescent agent specific for the target disease is imaged in order to navigate the surgical excision. As this technique quickly advances into the clinic, we hypothesize that the disease-specific fluorescence inherently contained within the resected tissues can be used to guide histopathological assessment. To evaluate the feasibility of fluorescence-guided pathology, we evaluated head and neck squamous cell carcinoma tumour specimens and margins resected from animals and patients after systemic injection of cetuximab-IRDye800CW. In a preclinical model of luciferase-positive tumour resection using bioluminescence as the gold standard, fluorescence assessment determined by closed-field fluorescence imaging of fresh resected margins accurately predicted the presence of disease in 33/39 positive margins yielding an overall sensitivity of 85%, specificity of 95%, positive predictive value (PPV) of 94%, and a negative predictive value (NPV) of 87%, which was superior to both surgical assessment (54%, 61%, 57%, and 58%) and pathological assessment (49%, 95%, 91%, and 66%), respectively. When the power of the technique was evaluated using human-derived tumour tissues, as little as 0.5mg (1mm(3)) of tumour tissue was identified (tumour-to-background-ratio:5.2). When the sensitivity/specificity of fluorescence-guided pathology was determined using traditional histological assessment as the gold standard in human tissues obtained during fluorescence-guided surgery, the technique was highly accurate with a sensitivity of 91

  1. Blockade of pathological retinal ganglion cell hyperactivity improves optogenetically evoked light responses in rd1 mice

    Directory of Open Access Journals (Sweden)

    John Martin Barrett

    2015-08-01

    Full Text Available Retinitis pigmentosa (RP is a progressive retinal dystrophy that causes visual impairment and eventual blindness. Retinal prostheses are the best currently available vision-restoring treatment for RP, but only restore crude vision. One possible contributing factor to the poor quality of vision achieved with prosthetic devices is the pathological retinal ganglion cell (RGC hyperactivity that occurs in photoreceptor dystrophic disorders. Gap junction blockade with meclofenamic acid (MFA was recently shown to diminish RGC hyperactivity and improve the signal-to-noise ratio (SNR of RGC responses to light flashes and electrical stimulation in the rd10 mouse model of RP. We sought to extend these results to spatiotemporally patterned optogenetic stimulation in the faster-degenerating rd1 model and compare the effectiveness of a number of drugs known to disrupt rd1 hyperactivity.We crossed rd1 mice with a transgenic mouse line expressing the light-sensitive cation channel channelrhodopsin2 (ChR2 in RGCs, allowing them to be stimulated directly using high-intensity blue light. We used 60-channel ITO multielectrode arrays to record ChR2-mediated RGC responses from wholemount, ex-vivo retinas to full-field and patterned stimuli before and after application of MFA, 18-ß-glycyrrhetinic acid (18BGA, another gap junction blocker or flupirtine (Flu, a Kv7 potassium channel opener. All three drugs decreased spontaneous RGC firing, but 18BGA and Flu also decreased the sensitivity of RGCs to optogenetic stimulation. Nevertheless, all three drugs improved the SNR of ChR2-mediated responses. MFA also made it easier to discern motion direction of a moving bar from RGC population responses.Our results support the hypothesis that reduction of pathological RGC spontaneous activity characteristic in retinal degenerative disorders may improve the quality of visual responses in retinal prostheses and they provide insights into how best to achieve this for optogenetic

  2. Blockade of pathological retinal ganglion cell hyperactivity improves optogenetically evoked light responses in rd1 mice.

    Science.gov (United States)

    Barrett, John M; Degenaar, Patrick; Sernagor, Evelyne

    2015-01-01

    Retinitis pigmentosa (RP) is a progressive retinal dystrophy that causes visual impairment and eventual blindness. Retinal prostheses are the best currently available vision-restoring treatment for RP, but only restore crude vision. One possible contributing factor to the poor quality of vision achieved with prosthetic devices is the pathological retinal ganglion cell (RGC) hyperactivity that occurs in photoreceptor dystrophic disorders. Gap junction blockade with meclofenamic acid (MFA) was recently shown to diminish RGC hyperactivity and improve the signal-to-noise ratio (SNR) of RGC responses to light flashes and electrical stimulation in the rd10 mouse model of RP. We sought to extend these results to spatiotemporally patterned optogenetic stimulation in the faster-degenerating rd1 model and compare the effectiveness of a number of drugs known to disrupt rd1 hyperactivity. We crossed rd1 mice with a transgenic mouse line expressing the light-sensitive cation channel channelrhodopsin2 (ChR2) in RGCs, allowing them to be stimulated directly using high-intensity blue light. We used 60-channel ITO multielectrode arrays to record ChR2-mediated RGC responses from wholemount, ex-vivo retinas to full-field and patterned stimuli before and after application of MFA, 18-β-glycyrrhetinic acid (18BGA, another gap junction blocker) or flupirtine (Flu, a Kv7 potassium channel opener). All three drugs decreased spontaneous RGC firing, but 18BGA and Flu also decreased the sensitivity of RGCs to optogenetic stimulation. Nevertheless, all three drugs improved the SNR of ChR2-mediated responses. MFA also made it easier to discern motion direction of a moving bar from RGC population responses. Our results support the hypothesis that reduction of pathological RGC spontaneous activity characteristic in retinal degenerative disorders may improve the quality of visual responses in retinal prostheses and they provide insights into how best to achieve this for optogenetic prostheses

  3. Overexpression of the IGF-II/M6P receptor in mouse fibroblast cell lines differentially alters expression profiles of genes involved in Alzheimer's disease-related pathology.

    Directory of Open Access Journals (Sweden)

    Yanlin Wang

    Full Text Available Alzheimer's disease (AD is the most common type of senile dementia affecting elderly people. The processing of amyloid precursor protein (APP leading to the generation of β-amyloid (Aβ peptide contributes to neurodegeneration and development of AD pathology. The endocytic trafficking pathway, which comprises of the endosomes and lysosomes, acts as an important site for Aβ generation, and endocytic dysfunction has been linked to increased Aβ production and loss of neurons in AD brains. Since insulin-like growth factor-II (IGF-II receptor plays a critical role in the transport of lysosomal enzymes from the trans-Golgi network to endosomes, it is likely that the receptor may have a role in regulating Aβ metabolism in AD pathology. However, very little is known on how altered levels of the IGF-II receptor can influence the expression/function of various molecules involved in AD pathology. To address this issue, we evaluated the expression profiles of 87 selected genes related to AD pathology in mouse fibroblast MS cells that are deficient in murine IGF-II receptor and corresponding MS9II cells overexpressing ∼ 500 times the human IGF-II receptors. Our results reveal that an elevation in IGF-II receptor levels alters the expression profiles of a number of genes including APP as well as enzymes regulating Aβ production, degradation and clearance mechanisms. Additionally, it influences the expression of various lysosomal enzymes and protein kinases that are involved in Aβ toxicity. IGF-II receptor overexpression also alters expression of several genes involved in intracellular signalling as well as cholesterol metabolism, which play a critical role in AD pathology. The altered gene profiles observed in this study closely match with the corresponding protein levels, with a few exceptions. These results, taken together, suggest that an elevation in IGF-II receptor levels can influence the expression profiles of transcripts as well as proteins

  4. Gastrointestinal B-cell lymphomas: From understanding B-cell physiology to classification and molecular pathology.

    Science.gov (United States)

    Sagaert, Xavier; Tousseyn, Thomas; Yantiss, Rhonda K

    2012-12-15

    The gut is the most common extranodal site where lymphomas arise. Although all histological lymphoma types may develop in the gut, small and large B-cell lymphomas predominate. The sometimes unexpected finding of a lymphoid lesion in an endoscopic biopsy of the gut may challenge both the clinician (who is not always familiar with lymphoma pathogenesis) and the pathologist (who will often be hampered in his/her diagnostic skill by the limited amount of available tissue). Moreover, the past 2 decades have spawned an avalanche of new data that encompasses both the function of the reactive B-cell as well as the pathogenic pathways that lead to its neoplastic counterpart, the B-cell lymphoma. Therefore, this review aims to offer clinicians an overview of B-cell lymphomas in the gut, and their pertinent molecular features that have led to new insights regarding lymphomagenesis. It addresses the question as how to incorporate all presently available information on normal and neoplastic B-cell differentiation, and how this knowledge can be applied in daily clinical practice (e.g., diagnostic tools, prognostic biomarkers or therapeutic targets) to optimalise the managment of this heterogeneous group of neoplasms. PMID:23443141

  5. Nondrowning Asphyxia in Veterinary Forensic Pathology: Suffocation, Strangulation, and Mechanical Asphyxia.

    Science.gov (United States)

    McEwen, B J

    2016-09-01

    Asphyxia in a forensic context refers to death by rapid cerebral anoxia or hypoxia due to accidental or nonaccidental injury. Death due to nondrowning asphyxia can occur with strangulation, suffocation, and mechanical asphyxia, each of which is categorized based on the mechanism of injury. Individuals dying due to various types of asphyxia may or may not have lesions, and even those lesions that are present may be due to other causes. The interpretation or opinion that death was due to asphyxia requires definitive and compelling evidence from the postmortem examination, death scene, and/or history. Beyond the postmortem examination, pathologists may be faced with questions of forensic importance that revolve around the behavioral and physiological responses in animals subjected to strangulation, suffocation, or mechanical asphyxia to determine if the animal suffered. While there is no prescriptive answer to these questions, it is apparent that, because of physiological and anatomical differences between humans and animals, for some mechanisms of asphyxia, consciousness is maintained for longer periods and the onset of death is later in animals than that described for people. Veterinary pathologists must be cognizant that direct extrapolation from the medical forensic literature to animals may be incorrect. This article reviews the terminology, classification, mechanisms, and lesions associated with asphyxial deaths in companion animals and highlights significant comparative differences of the response to various types of asphyxia in animals and people. PMID:27084399

  6. Predicting non-small cell lung cancer prognosis by fully automated microscopic pathology image features

    Science.gov (United States)

    Yu, Kun-Hsing; Zhang, Ce; Berry, Gerald J.; Altman, Russ B.; Ré, Christopher; Rubin, Daniel L.; Snyder, Michael

    2016-01-01

    Lung cancer is the most prevalent cancer worldwide, and histopathological assessment is indispensable for its diagnosis. However, human evaluation of pathology slides cannot accurately predict patients' prognoses. In this study, we obtain 2,186 haematoxylin and eosin stained histopathology whole-slide images of lung adenocarcinoma and squamous cell carcinoma patients from The Cancer Genome Atlas (TCGA), and 294 additional images from Stanford Tissue Microarray (TMA) Database. We extract 9,879 quantitative image features and use regularized machine-learning methods to select the top features and to distinguish shorter-term survivors from longer-term survivors with stage I adenocarcinoma (P<0.003) or squamous cell carcinoma (P=0.023) in the TCGA data set. We validate the survival prediction framework with the TMA cohort (P<0.036 for both tumour types). Our results suggest that automatically derived image features can predict the prognosis of lung cancer patients and thereby contribute to precision oncology. Our methods are extensible to histopathology images of other organs. PMID:27527408

  7. Cancer Cell Fusion: Mechanisms Slowly Unravel

    Science.gov (United States)

    Noubissi, Felicite K.; Ogle, Brenda M.

    2016-01-01

    Although molecular mechanisms and signaling pathways driving invasion and metastasis have been studied for many years, the origin of the population of metastatic cells within the primary tumor is still not well understood. About a century ago, Aichel proposed that cancer cell fusion was a mechanism of cancer metastasis. This hypothesis gained some support over the years, and recently became the focus of many studies that revealed increasing evidence pointing to the possibility that cancer cell fusion probably gives rise to the metastatic phenotype by generating widespread genetic and epigenetic diversity, leading to the emergence of critical populations needed to evolve resistance to the treatment and development of metastasis. In this review, we will discuss the clinical relevance of cancer cell fusion, describe emerging mechanisms of cancer cell fusion, address why inhibiting cancer cell fusion could represent a critical line of attack to limit drug resistance and to prevent metastasis, and suggest one new modality for doing so. PMID:27657058

  8. T cell migration, search strategies and mechanisms.

    Science.gov (United States)

    Krummel, Matthew F; Bartumeus, Frederic; Gérard, Audrey

    2016-03-01

    T cell migration is essential for T cell responses; it allows for the detection of cognate antigen at the surface of antigen-presenting cells and for interactions with other cells involved in the immune response. Although appearing random, growing evidence suggests that T cell motility patterns are strategic and governed by mechanisms that are optimized for both the activation stage of the cell and for environment-specific cues. In this Opinion article, we discuss how the combined effects of T cell-intrinsic and -extrinsic forces influence T cell motility patterns in the context of highly complex tissues that are filled with other cells involved in parallel motility. In particular, we examine how insights from 'search theory' can be used to describe T cell movement across an 'exploitation-exploration trade-off' in the context of activation versus effector function and lymph nodes versus peripheral tissues. PMID:26852928

  9. Mechanisms of cell propulsion by active stresses

    Energy Technology Data Exchange (ETDEWEB)

    Carlsson, A E, E-mail: aec@wustl.edu [Department of Physics, Washington University, Campus Box 1105, One Brookings Drive, St. Louis, MO 63130 (United States)

    2011-07-15

    The mechanisms by which cytoskeletal flows and cell-substrate interactions interact to generate cell motion are explored by using a simplified model of the cytoskeleton as a viscous gel containing active stresses. This model yields explicit general results relating cell speed and traction forces to the distributions of active stress and cell-substrate friction. It is found that (i) the cell velocity is given by a function that quantifies the asymmetry of the active-stress distribution, (ii) gradients in cell-substrate friction can induce motion even when the active stresses are symmetrically distributed, (iii) the traction-force dipole is enhanced by protrusive stresses near the cell edges or contractile stresses near the center of the cell and (iv) the cell velocity depends biphasically on the cell-substrate adhesion strength if active stress is enhanced by adhesion. Specific experimental tests of the calculated dependences are proposed.

  10. Early Biomarkers in 1H Nuclear Magnetic Resonance Spectroscopy of Striatal Pathological Mechanisms after Acute Carbon Monoxide Poisoning in Rats

    Institute of Scientific and Technical Information of China (English)

    GUAN Li; LI Zong Yang; ZHANG Yan Lin; CONG Cui Cui; ZHAO Jin Yuan

    2015-01-01

    Objective In vivo Proton Magnetic Resonance Spectroscopy (1H-MRS) can be used to evaluate the levels of specific neurochemical biomarkers of pathological mechanisms in the brain. Methods We conducted T2-Weighted Magnetic Resonance Imaging (MRI) and 1H-MRS with a 3.0-Tesla animal MRI system to investigate the early microstructural and metabolic profiles in vivo in the striatum of rats following carbon monoxide (CO) poisoning. Results Compared to baseline, we found significant cortical surface deformation, cerebral edema changes, which were indicated by the unclear gray/white matter border, and lateral ventricular volume changes in the brain. A significant reduction in the metabolite to total creatine (Cr) ratios of N-acetylaspartate (NAA) was observed as early as 1 h after the last CO administration, while the lactate (Lac) levels increased marginally. Both the Lac/Cr and NAA/Cr ratios leveled off at 6 h and showed no subsequent significant changes. In addition, compared to the control, the choline (Cho)/Cr ratio was slightly reduced in the early stages and significantly increased after 6 h. In addition, a pathological examination revealed mild cerebral edema on cessation of the insult and more severe cerebral injury after additional CO poisoning. Conclusion The present study demonstrated that 1H-MRS of the brain identified early metabolic changes after CO poisoning. Notably, the relationship between the increased Cho/Cr ratio in the striatum and delayed neuropsychologic sequelae requires further research.

  11. Gastrointestinal B-cell lymphomas: From understanding B-cell physiology to classification and molecular pathology

    OpenAIRE

    2012-01-01

    The gut is the most common extranodal site where lymphomas arise. Although all histological lymphoma types may develop in the gut, small and large B-cell lymphomas predominate. The sometimes unexpected finding of a lymphoid lesion in an endoscopic biopsy of the gut may challenge both the clinician (who is not always familiar with lymphoma pathogenesis) and the pathologist (who will often be hampered in his/her diagnostic skill by the limited amount of available tissue). Moreover, the past 2 d...

  12. Pathologic characteristics of resected squamous cell carcinoma of the trachea: prognostic factors based on an analysis of 59 cases.

    NARCIS (Netherlands)

    Honings, J.; Gaissert, H.A.; Ruangchira-Urai, R.; Wain, J.C.; Wright, C.D.; Mathisen, D.J.; Mark, E.J.

    2009-01-01

    While squamous cell carcinoma (SCC) is the most common tracheal malignancy, few reports describe the pathologic considerations that may guide intraoperative decisions and prognostic assessment. We reviewed 59 tracheal SCC treated between 1985 and 2008 by segmental resection of the trachea, including

  13. Identification of the cellular mechanisms undelying the contribution of stress and glucocorticoids to Alzheimer's disease pathology

    OpenAIRE

    Sotiropoulos, Ioannis

    2006-01-01

    Clinical evidence suggests the involvement of stress and glucocorticoids (GC) in the etiopathogenesis of Alzheimer’s disease (AD), a disease marked by severe memory impairments as well as alterations in mood and emotional state. The experiments described in this dissertation represent an attempt to establish the cellular mechanisms through which stress and GC may impact on the development of AD. These studies focused on the hippocampus and prefrontal cortex (PFC), brain areas that are severel...

  14. BASEBALL THROWING MECHANICS AS THEY RELATE TO PATHOLOGY AND PERFORMANCE - A REVIEW

    OpenAIRE

    Rod Whiteley

    2007-01-01

    It is a commonly held perception amongst biomechanists, sports medicine practitioners, baseball coaches and players, that an individual baseball player's style of throwing or pitching influences their performance and susceptibility to injury. With the results of a series of focus groups with baseball managers and pitching coaches in mind, the available scientific literature was reviewed regarding the contribution of individual aspects of pitching and throwing mechanics to potential for injury...

  15. Molecular mechanisms of fibroblast growth factor signaling in physiology and pathology.

    Science.gov (United States)

    Belov, Artur A; Mohammadi, Moosa

    2013-06-01

    Fibroblast growth factors (FGFs) signal in a paracrine or endocrine fashion to mediate a myriad of biological activities, ranging from issuing developmental cues, maintaining tissue homeostasis, and regulating metabolic processes. FGFs carry out their diverse functions by binding and dimerizing FGF receptors (FGFRs) in a heparan sulfate (HS) cofactor- or Klotho coreceptor-assisted manner. The accumulated wealth of structural and biophysical data in the past decade has transformed our understanding of the mechanism of FGF signaling in human health and development, and has provided novel concepts in receptor tyrosine kinase (RTK) signaling. Among these contributions are the elucidation of HS-assisted receptor dimerization, delineation of the molecular determinants of ligand-receptor specificity, tyrosine kinase regulation, receptor cis-autoinhibition, and tyrosine trans-autophosphorylation. These structural studies have also revealed how disease-associated mutations highjack the physiological mechanisms of FGFR regulation to contribute to human diseases. In this paper, we will discuss the structurally and biophysically derived mechanisms of FGF signaling, and how the insights gained may guide the development of therapies for treatment of a diverse array of human diseases. PMID:23732477

  16. Famotidine suppresses osteogenic differentiation of tendon cells in vitro and pathological calcification of tendon in vivo.

    Science.gov (United States)

    Yamamoto, Kenichi; Hojo, Hironori; Koshima, Isao; Chung, Ung-il; Ohba, Shinsuke

    2012-12-01

    Heterotopic ossification or calcification follows any type of musculoskeletal trauma and is known to occur after arthroplasties of hip, knee, shoulder, or elbow; fractures; joint dislocations; or tendon ruptures. Histamine receptor H2 (Hrh2) has been shown to be effective for reducing pain and decreasing calcification in patients with calcifying tendinitis, which suggested that H2 blockers were effective for the treatment of tendon ossification or calcification. However, the detailed mechanisms of its action on tendon remain to be clarified. We investigated the mechanisms underlying H2 blocker-mediated suppression of tendon calcification, with a focus on the direct action of the drug on tendon cells. Famotidine treatment suppressed the mRNA expressions of Col10a1 and osteocalcin, ossification markers, in a tendon-derived cell line TT-D6, as well as a preosteoblastic one MC3T3-E1. Both of the cell lines expressed Hrh2; histamine treatment induced osteocalcin expression in these cells. Famotidine administration suppressed calcification in the Achilles tendon of ttw mice, a mouse model of ectopic ossification. These data suggest that famotidine inhibits osteogenic differentiation of tendon cells in vitro, and this inhibition may underlie the anti-calcification effects of the drug in vivo. This study points to the use of H2 blockers as a promising strategy for treating heterotopic ossification or calcification in tendon, and provides evidence in support of the clinical use of famotidine.

  17. Oxyphil Cell Parathyroid Adenomas Causing Primary Hyperparathyroidism: a Clinico-Pathological Correlation.

    Science.gov (United States)

    Howson, Pamela; Kruijff, Schelto; Aniss, Ahmad; Pennington, Thomas; Gill, Anthony J; Dodds, Tristan; Delbridge, Leigh W; Sidhu, Stan B; Sywak, Mark S

    2015-09-01

    Oxyphil cell parathyroid adenomas (OPA) are considered to be an uncommon cause of primary hyperparathyroidism (PHPT), and were historically thought to be clinically silent. It has been our clinical impression that these adenomas present more often than previously thought and may manifest a more severe form of primary hyperparathyroidism than classical adenoma. The aim of this study was to describe the incidence and clinical presentation of OPA. An observational case-control study was undertaken. The study group comprised patients undergoing parathyroidectomy for PHPT where the final pathology confirmed OPA. The controls were made up of an age- and sex-matched group of patients having parathyroidectomy in the same time period where the final pathology confirmed a classical or non-oxyphil adenoma. OPA were defined as parathyroid tumours containing >75% oxyphilic cells. The OPA cases were obtained by reviewing all histopathology slides over an 11-year period (2002-12) where the reports contained the words 'oxyphil' or 'oxyphilic' parathyroid adenomas. These were then reviewed by two independent pathologists to confirm a diagnosis of OPA. The primary outcome measures were preoperative serum calcium and parathyroid hormone (PTH) levels. Secondary outcome measures were symptoms at presentation, accuracy of preoperative localization studies, parathyroid gland weight following surgery, and type of surgery undertaken. In the period 2002-2012, 2739 patients underwent surgery for PHPT. Following pathological review, 91 cases were confirmed as being OPA and formed the study group. A control group (n = 91) from the same period was selected following matching on the basis of age at presentation and sex. OPA were associated with higher preoperative serum calcium (10.84 versus 10.48 mg/dL, p < 0.001) and parathyroid hormone (139 versus 64 ng/L, p < 0.001). At presentation, a lower proportion of OPA cases had asymptomatic disease (15 versus 29%, p = 0.03). There was

  18. Mechanisms of DNA uptake by cells

    Energy Technology Data Exchange (ETDEWEB)

    Lacks, S.A.

    1977-01-01

    Three categories of cellular uptake of DNA can be distinguished. First, in the highly transformable bacteria, such as Diplococcus pneumoniae, Haemophilus influenzae and Bacillus subtilis, elaborate mechanisms of DNA transport have evolved, presumably for the purpose of genetic exchange. These mechanisms can introduce substantial amounts of DNA into the cell. Second, methods have been devised for the forced introduction of DNA by manipulation of bacterial cells under nonphysiological conditions. By such means small but significant amounts of DNA have been introduced into various bacteria, including Escherichia coli. Third, mammalian cells are able to take up biologically active DNA. This has been most clearly demonstrated with viral DNA, although the mechanism of uptake is not well understood. The intention, here, is to survey current understanding of the various mechanisms of DNA uptake. A review of experience with the bacterial systems may throw some light on the mammalian system and lead to suggestions for enhancing DNA uptake by mammalian cells.

  19. Peripheral nerve pathology, including aberrant Schwann cell differentiation, is ameliorated by doxycycline in a laminin-α2-deficient mouse model of congenital muscular dystrophy

    OpenAIRE

    Homma, Sachiko; Beermann, Mary Lou; Miller, Jeffrey Boone

    2011-01-01

    The most common form of childhood congenital muscular dystrophy, Type 1A (MDC1A), is caused by mutations in the human LAMA2 gene that encodes the laminin-α2 subunit. In addition to skeletal muscle deficits, MDC1A patients typically show a loss of peripheral nerve function. To identify the mechanisms underlying this loss of nerve function, we have examined pathology and cell differentiation in sciatic nerves and ventral roots of the laminin-α2-deficient (Lama2−/−) mice, which are models for MD...

  20. Desmoplastic Small Round Cell Tumor of the Kidney: AIRP Best Cases in Radiologic-Pathologic Correlation.

    Science.gov (United States)

    Walton, William J; Flores, Raina R

    2016-01-01

    Editor's Note.-RadioGraphics continues to publish radiologic-pathologic case material selected from the American Institute for Radiologic Pathology (AIRP) "best case" presentations. The AIRP conducts a 4-week Radiologic Pathology Correlation Course, which is offered five times per year. On the penultimate day of the course, the best case presentation is held at the American Film Institute Silver Theater and Cultural Center in Silver Spring, Md. The AIRP faculty identifies the best cases, from each organ system, brought by the resident attendees. One or more of the best cases from each of the five courses are then solicited for publication in RadioGraphics. These cases emphasize the importance of radiologic-pathologic correlation in the imaging evaluation and diagnosis of diseases encountered at the institute and its predecessor, the Armed Forces Institute of Pathology (AFIP).

  1. Adrenergic mechanism responsible for pathological alteration in gastric mucosal blood flow in rats with ulcer bleeding

    Science.gov (United States)

    Semyachkina-Glushkovskaya, O. V.; Pavlov, A. N.; Semyachkin-Glushkovskiy, I. A.; Gekalyuk, A. S.; Ulanova, M. V.; Lychagov, V. V.; Tuchin, V. V.

    2014-09-01

    The adrenergic system plays an important role in regulation of central and peripheral circulation in normal state and during hemorrhage. Because the impaired gastric mucosal blood flow (GMBF) is the major cause of gastroduodenal lesions, including ulcer bleeding (UB), we studied the adrenergic mechanism responsible for regulation of GMBF in rats with a model of stress-induced UB (SUB) using the laser Doppler flowmetry (LDF). First, we examined the effect of adrenaline on GMBF in rats under normal state and during UB. In all healthy animals the submucosal adrenaline injection caused a decrease in local GMBF. During UB the submucosal injection of adrenaline was accompanied by less pronounced GMBF suppression in 30,3% rats with SUB vs. healthy ones. In 69,7% rats with SUB we observed the increase in local GMBF after submucosal injection of adrenaline. Second, we studied the sensitivity of gastric β2-adrenoreceptors and the activity of two factors which are involved in β2-adrenomediated vasorelaxation-KATP -channels and NO. The effects of submucosal injection of isoproterenol, ICI118551 and glybenclamide on GMBF as well as NO levels in gastric tissue were significantly elevated in rats with SUB vs. healthy rats. Thus, our results indicate that high activation of gastric β2-adrenoreceptors associated with the increased vascular KATP -channels activity and elevated NO production is the important adrenergic mechanism implicated in the pathogenesis of UB.

  2. Nanodiamond internalization in cells and the cell uptake mechanism

    International Nuclear Information System (INIS)

    Cell type-dependent penetration of nanodiamond in living cells is one of the important factors for using nanodiamond as cellular markers/labels, for drug delivery as well as for other biomedical applications. In this work, internalization of 100 nm nanodiamonds by A549 lung human adenocarcinoma cell, Beas-2b non-tumorigenic human bronchial epithelial cell, and HFL-1 fibroblast-like human fetal lung cell is studied and compared. The penetration of nanodiamond into the cells was observed using confocal fluorescence imaging and Raman imaging methods. Visualization of the nanodiamond in cells allows comparison of the internalization for diamond nanoparticles in cancer A549 cell, non-cancer HFL-1, and Beas-2b cells. The dose-dependent and time-dependent behavior of nanodiamond uptake is observed in both cancer as well as non-cancer cells. The mechanism of nanodiamond uptake by cancer and non-cancer cells is analyzed by blocking different pathways. The uptake of nanodiamond in both cancer and non-cancer cells was found predominantly via clathrin-dependent endocytosis. In spite of observed similarity in the uptake mechanism for cancer and non-cancer cells, the nanodiamond uptake for cancer cell quantitatively exceeds the uptake for non-cancer cells, for the studied cell lines. The observed difference in internalization of nanodiamond by cancer and non-cancer cells is discussed

  3. Nanodiamond internalization in cells and the cell uptake mechanism

    Energy Technology Data Exchange (ETDEWEB)

    Perevedentseva, E. [National Dong Hwa University, Department of Physics (China); Hong, S.-F.; Huang, K.-J. [National Dong Hwa University, Department of Life Sciences (China); Chiang, I.-T.; Lee, C.-Y. [National Dong Hwa University, Department of Physics (China); Tseng, Y.-T. [National Dong Hwa University, Department of Life Sciences (China); Cheng, C.-L., E-mail: clcheng@mail.ndhu.edu.tw [National Dong Hwa University, Department of Physics (China)

    2013-08-15

    Cell type-dependent penetration of nanodiamond in living cells is one of the important factors for using nanodiamond as cellular markers/labels, for drug delivery as well as for other biomedical applications. In this work, internalization of 100 nm nanodiamonds by A549 lung human adenocarcinoma cell, Beas-2b non-tumorigenic human bronchial epithelial cell, and HFL-1 fibroblast-like human fetal lung cell is studied and compared. The penetration of nanodiamond into the cells was observed using confocal fluorescence imaging and Raman imaging methods. Visualization of the nanodiamond in cells allows comparison of the internalization for diamond nanoparticles in cancer A549 cell, non-cancer HFL-1, and Beas-2b cells. The dose-dependent and time-dependent behavior of nanodiamond uptake is observed in both cancer as well as non-cancer cells. The mechanism of nanodiamond uptake by cancer and non-cancer cells is analyzed by blocking different pathways. The uptake of nanodiamond in both cancer and non-cancer cells was found predominantly via clathrin-dependent endocytosis. In spite of observed similarity in the uptake mechanism for cancer and non-cancer cells, the nanodiamond uptake for cancer cell quantitatively exceeds the uptake for non-cancer cells, for the studied cell lines. The observed difference in internalization of nanodiamond by cancer and non-cancer cells is discussed.

  4. Pathology of human plaque vulnerability: mechanisms and consequences of intraplaque haemorrhages.

    Science.gov (United States)

    Michel, Jean-Baptiste; Martin-Ventura, José Luis; Nicoletti, Antonino; Ho-Tin-Noé, Benoit

    2014-06-01

    Atherothrombotic diseases are still major causes of inability and mortality and fighting atherothrombosis remains a public health priority. The involvement of repeated intraplaque haemorrhages (IPH) in the evolution of atherothrombotic lesions towards complications was proposed as early as 1936. This important topic has been recently revisited and reviewed. Histological observations have been corroborated by magnetic resonance imaging (MRI) of human carotid atheroma, identifying IPH as the main determinant of plaque evolution towards rupture. Beside the intimal integration of asymptomatic luminal coagulum, inward sprouting of neovessels from the adventitia towards the plaque, is one source of IPH in human atheroma. We recently described that directed neo-angiogenesis from the adventitia towards the plaque, across the media, is initiated by lipid mediators generated by the plaque on the luminal side, outwardly convected to the medial VSMCs. Subsequent stimulation of VSMC PPAR-γ receptors induces VEGF expression which causes centripetal sprouting of adventitial vessels. However, this neovascularization is considered to be immature and highly susceptible to leakage. The main cellular components of IPH are Red Blood Cells (RBCs), which with their haemoglobin content and their cell membrane components, particularly enriched in unesterified cholesterol, participate in both the oxidative process and cholesterol accumulation. The presence of iron, glycophorin A and ceroids provides evidence of RBCs. IPH also convey blood leukocytes and platelets and are sites prone to weak pathogen contamination. Therefore prevention and treatment of the biological consequences of IPH pave the way to innovative preventive strategies and improved therapeutic options in human atherothrombotic diseases. PMID:24726899

  5. Quantitative & qualitative analysis of endothelial cells of donor cornea before & after penetrating keratoplasty in different pathological conditions

    Directory of Open Access Journals (Sweden)

    Aruna K.R. Gupta

    2016-01-01

    Full Text Available Background & objectives: Endothelial cells of the donor cornea are known to be affected quantitatively and qualitatively in different pathological conditions after penetrating keratoplasty (PK and this has direct effect on the clarity of vision obtained after PK. This study was undertaken to analyze the qualitative and quantitative changes in donor endothelial cells before and after PK in different pathological conditions. Methods: A prospective investigational analysis of 100 consecutive donor corneas used for penetrating keratoplasty between June 2006 and June 2008, was conducted. The patients were evaluated on the first day, at the end of first week, first month, third and six months and one year. Results: A decrease was observed in endothelial cell count in all pathological conditions. After one year of follow up the loss was 33.1 per cent in corneal opacity, 45.9 per cent in acute infective keratitis (AIK, 58.5 per cent in regrafts, 28.5 per cent in pseudophakic bullous keratopathy (PBK, 37 per cent in descemetocele, 27 per cent in keratoconus and 35.5 per cent in aphakic bullous keratopathy (ABK cases. Interpretation & conclusions: The endothelial cell loss was highest in regraft cases which was significant (P<0.05, while the least endothelial cell loss was seen in keratoconus cases. The cell loss was associated with increase in coefficient of variation (CV, i.e. polymegathism and pleomorphism. Inspite of this polymegathism and pleomorphism, the clarity of the graft was maintained.

  6. Environmental properties set cell mechanics and morphology

    Science.gov (United States)

    Janmey, Paul

    2012-02-01

    Many cell types are sensitive to mechanical signals that are produced either by application of exogenous force to their surfaces, or by the resistance that their surroundings place on forces generated by the cells themselves. Cell morphology, motility, proliferation, and protein expression all change in response to substrate stiffness. Changing the elastic moduli of substrates alters the formation of focal adhesions, the assembly of actin filaments into bundles, and the stability of intermediate filaments. The range of stiffness over which different primary cell types respond can vary over a wide range and generally reflects the elastic modulus of the tissue from which these cells were isolated. Mechanosensing depends on the type of adhesion receptor by which the cell binds, and therefore on both the molecular composition of the extracellular matrix and the nature of its link to the cytoskeleton. Many cell types can alter their own stiffness to match that of the substrate to which they adhere. The maximal elastic modulus that cells such as fibroblasts can attain is similar to that of crosslinked actin networks at the concentrations in the cell cortex. The precise mechanisms of mechanosensing are not well defined, but they presumably require an elastic connection between cell and substrate, mediated by transmembrane proteins. The viscoelastic properties of different extracellular matrices and cytoskeletal elements strongly influence the response of cells to mechanical signals, and the unusual non-linear elasticity of many biopolymer gels, characterized by strain-stiffening, leads to novel mechanisms by which cells alter their stiffness by engagement of molecular motors that produce internal stresses. Cell cortical elasticity is dominated by cytoskeletal polymer networks and can be modulated by internal tension. Simultaneous control of substrate stiffness and adhesive patterns suggests that stiffness sensing occurs on a length scale much larger than single molecular

  7. Polymer microlenses for quantifying cell sheet mechanics.

    Science.gov (United States)

    Miquelard-Garnier, Guillaume; Zimberlin, Jessica A; Sikora, Christian B; Wadsworth, Patricia; Crosby, Alfred

    2010-01-01

    Mechanical interactions between individual cells and their substrate have been studied extensively over the past decade; however, understanding how these interactions change as cells interact with neighboring cells in the development of a cell sheet, or early stage tissue, is less developed. We use a recently developed experimental technique for quantifying the mechanics of confluent cell sheets. Living cells are cultured on a thin film of polystyrene [PS], which is attached to a patterned substrate of crosslinked poly(dimethyl siloxane) [PDMS] microwells. As cells attach to the substrate and begin to form a sheet, they apply sufficient contractile force to buckle the PS film over individual microwells to form a microlens array. The curvature for each microlens is measured by confocal microscopy and can be related to the strain and stress applied by the cell sheet using simple mechanical analysis for the buckling of thin films. We demonstrate that this technique can provide insight into the important materials properties and length scales that govern cell sheet responses, especially the role of stiffness of the substrate. We show that intercellular forces can lead to significantly different behaviors than the ones observed for individual cells, where focal adhesion is the relevant parameter.

  8. Allosuppressor- and allohelper-T cells in acute and chronic graft-vs. -host (GVH) disease. III. Different Lyt subsets of donor T cells induce different pathological syndromes

    Energy Technology Data Exchange (ETDEWEB)

    Rolink, A.G.; Gleichmann, E.

    1983-08-01

    Previous work from this laboratory has led to the hypothesis that the stimulatory pathological symptoms of chronic graft-vs.-host disease (GVHD) are caused by alloreactive donor T helper (TH) cells, whereas the suppressive pathological symptoms of acute GVHD are caused by alloreactive T suppressor (TS) cells of the donor. We analyzed the Lyt phenotypes of B10 donor T cells required for the induction of either acute or chronic GVHD in H-2-different (B10 X DBA/2)F1 recipients. When nonirradiated F1 mice were used as the recipients, we found unseparated B10 T cells induced only a moderate formation of systemic lupus erythematosus (SLE)-like autoantibodies, but a high percentage of lethal GVHD (LGVHD). In contrast, Lyt-1+2- donor T cells were unable to induce LGVHD in these recipients but were capable of inducing a vigorous formation of SLE-like autoantibodies and severe immune-complex glomerulonephritis. Lyt-1-2+ T cells were incapable of inducing either acute or chronic GVHD. The sensitivity and accuracy of the GVH system were increased by using irradiated F1 mice as recipients and then comparing donor-cell inocula that contained similar numbers of T lymphocytes. Donor-cell inocula were used that had been tested for their allohelper and allosuppressor effects on F1 B cells in vitro. In the irradiated F1 recipients unseparated donor T cells were superior to T cell subsets in inducing LGVHD. In contrast Lyt-1+2- T cells, but neither unseparated T cells nor Lyt-1-2+ T cells, were capable of inducing a vigorous formation of SLE-like auto-antibodies. We conclude that the stimulatory pathological symptoms of chronic GVHD are caused by Lyt-1+2- allohelper T cells. In contrast, the development of the suppressive pathological symptoms of acute GVHD appears to involve alloreactive Lyt-1+2+ T suppressor cells.

  9. Physiological, pathological, and engineered cell identity reprogramming in the central nervous system.

    Science.gov (United States)

    Smith, Derek K; Wang, Lei-Lei; Zhang, Chun-Li

    2016-07-01

    Multipotent neural stem cells persist in restricted regions of the adult mammalian central nervous system. These proliferative cells differentiate into diverse neuron subtypes to maintain neural homeostasis. This endogenous process can be reprogrammed as a compensatory response to physiological cues, traumatic injury, and neurodegeneration. In addition to innate neurogenesis, recent research has demonstrated that new neurons can be engineered via cell identity reprogramming in non-neurogenic regions of the adult central nervous system. A comprehensive understanding of these reprogramming mechanisms will be essential to the development of therapeutic neural regeneration strategies that aim to improve functional recovery after injury and neurodegeneration. WIREs Dev Biol 2016, 5:499-517. doi: 10.1002/wdev.234 For further resources related to this article, please visit the WIREs website. PMID:27258392

  10. The Mechanics of Mitotic Cell Rounding

    OpenAIRE

    Stewart, Martin

    2012-01-01

    During mitosis, adherent animal cells undergo a drastic shape change, from essentially flat to round, in a process known as mitotic cell rounding (MCR). The aim of this thesis was to critically examine the physical and biological basis of MCR. The experimental part of this thesis employed a combined optical microscope-atomic force microscope (AFM) setup in conjunction with flat tipless cantilevers to analyze cell mechanics, shape and volume. To this end, two AFM assays were developed: the ...

  11. Investigating cell mechanics with atomic force microscopy.

    Science.gov (United States)

    Haase, Kristina; Pelling, Andrew E

    2015-03-01

    Transmission of mechanical force is crucial for normal cell development and functioning. However, the process of mechanotransduction cannot be studied in isolation from cell mechanics. Thus, in order to understand how cells 'feel', we must first understand how they deform and recover from physical perturbations. Owing to its versatility, atomic force microscopy (AFM) has become a popular tool to study intrinsic cellular mechanical properties. Used to directly manipulate and examine whole and subcellular reactions, AFM allows for top-down and reconstitutive approaches to mechanical characterization. These studies show that the responses of cells and their components are complex, and largely depend on the magnitude and time scale of loading. In this review, we generally describe the mechanotransductive process through discussion of well-known mechanosensors. We then focus on discussion of recent examples where AFM is used to specifically probe the elastic and inelastic responses of single cells undergoing deformation. We present a brief overview of classical and current models often used to characterize observed cellular phenomena in response to force. Both simple mechanistic models and complex nonlinear models have been used to describe the observed cellular behaviours, however a unifying description of cell mechanics has not yet been resolved. PMID:25589563

  12. Effect of bone marrow derived mesenchymal stem cells on lung pathology and inflammation in ovalbumin-induced asthma in mouse

    Directory of Open Access Journals (Sweden)

    Maryam Mohammadian

    2016-01-01

    Full Text Available Objective(s:Bone marrow-derived mesenchymal stem cells (BMSCs have attracted significant interest to treat asthma and its complication. In this study, the effects of BMSCs on lung pathology and inflammation in an ovalbumin-induced asthma model in mouse were examined. Materials and Methods:BALB/c mice were divided into three groups: control group (animals were not sensitized, asthma group (animals were sensitized by ovalbumin, asthma+BMSC group (animals were sensitized by ovalbumin and treated with BMSCs. BMSCs were isolated and characterized and then labeled with Bromodeoxyuridine (BrdU. After that the cells transferred into asthmatic mice. Histopathological changes of the airways, BMSCs migration and total and differential white blood cell (WBC count in bronchoalveolar lavage (BAL fluid were evaluated. Results:A large number of BrdU-BMSCs were found in the lungs of mice treated with BMSCs. The histopathological changes, BAL total WBC counts and the percentage of neutrophils and eosinophils were increased in asthma group compared to the control group. Treatment with BMSCs significantly decreased airway pathological indices, inflammatory cell infiltration, and also goblet cell hyperplasia. Conclusion:The results of this study revealed that BMSCs therapy significantly suppressed the lung pathology and inflammation in the ovalbumin induced asthma model in mouse.

  13. The role of biofluid mechanics in the assessment of clinical and pathological observations: sixth International Bio-Fluid Mechanics Symposium and Workshop, March 28-30, 2008 Pasadena, California

    NARCIS (Netherlands)

    M. Siebes; Y. Ventikos

    2010-01-01

    Biofluid mechanics is increasingly applied in support of diagnosis and decision-making for treatment of clinical pathologies. Exploring the relationship between blood flow phenomena and pathophysiological observations is enhanced by continuing advances in the imaging modalities, measurement techniqu

  14. The cytokines interleukin 27 and interferon-γ promote distinct Treg cell populations required to limit infection-induced pathology.

    Science.gov (United States)

    Hall, Aisling O'Hara; Beiting, Daniel P; Tato, Cristina; John, Beena; Oldenhove, Guillaume; Lombana, Claudia Gonzalez; Pritchard, Gretchen Harms; Silver, Jonathan S; Bouladoux, Nicolas; Stumhofer, Jason S; Harris, Tajie H; Grainger, John; Wojno, Elia D Tait; Wagage, Sagie; Roos, David S; Scott, Philip; Turka, Laurence A; Cherry, Sara; Reiner, Steven L; Cua, Daniel; Belkaid, Yasmine; Elloso, M Merle; Hunter, Christopher A

    2012-09-21

    Interferon-γ (IFN-γ) promotes a population of T-bet(+) CXCR3(+) regulatory T (Treg) cells that limit T helper 1 (Th1) cell-mediated pathology. Our studies demonstrate that interleukin-27 (IL-27) also promoted expression of T-bet and CXCR3 in Treg cells. During infection with Toxoplasma gondii, a similar population emerged that limited T cell responses and was dependent on IFN-γ in the periphery but on IL-27 at mucosal sites. Transfer of Treg cells ameliorated the infection-induced pathology observed in Il27(-/-) mice, and this was dependent on their ability to produce IL-10. Microarray analysis revealed that Treg cells exposed to either IFN-γ or IL-27 have distinct transcriptional profiles. Thus, IFN-γ and IL-27 have different roles in Treg cell biology and IL-27 is a key cytokine that promotes the development of Treg cells specialized to control Th1 cell-mediated immunity at local sites of inflammation.

  15. [Key molecular mechanisms associated with cell malignant transformation in acute myeloid leukemia].

    Science.gov (United States)

    Orlova, N N; Lebedev, T D; Spirin, P V; Prassolov, V S

    2016-01-01

    Cancer, along with cardiovascular disorders, is one of the most important problems of healthcare. Pathologies of the hematopoietic system are the most prevalent in patients under 30 years of age, including acute myeloid leukemia (AML), which is widespread and difficult to treat. The review considers the mechanisms that play a significant role in AML cell malignant transformation and shows the contributions of certain genes to both remission and resistance of AML cells to various treatments.

  16. Pathological mechanism for delayed hyperenhancement of chronic scarred myocardium in contrast agent enhanced magnetic resonance imaging.

    Directory of Open Access Journals (Sweden)

    Jian Wang

    Full Text Available OBJECTIVES: To evaluate possible mechanism for delayed hyperenhancement of scarred myocardium by investigating the relationship of contrast agent (CA first pass and delayed enhancement patterns with histopathological changes. MATERIALS AND METHODS: Eighteen pigs underwent 4 weeks ligation of 1 or 2 diagonal coronary arteries to induce chronic infarction. The hearts were then removed and perfused in a Langendorff apparatus. The hearts firstly experienced phosphorus 31 MR spectroscopy. The hearts in group I (n = 9 and II (n = 9 then received the bolus injection of Gadolinium diethylenetriamine pentaacetic acid (0.05 mmol/kg and gadolinium-based macromolecular agent (P792, 15 µmol/kg, respectively. First pass T2* MRI was acquired using a gradient echo sequence. Delayed enhanced T1 MRI was acquired with an inversion recovery sequence. Masson's trichrome and anti- von Willebrand Factor (vWF staining were performed for infarct characterization. RESULTS: Wash-in of both kinds of CA caused the sharp and dramatic T2* signal decrease of scarred myocardium similar to that of normal myocardium. Myocardial blood flow and microvessel density were significantly recovered in 4-week-old scar tissue. Steady state distribution volume (ΔR1 relaxation rate of Gd-DTPA was markedly higher in scarred myocardium than in normal myocardium, whereas ΔR1 relaxation rate of P792 did not differ significantly between scarred and normal myocardium. The ratio of extracellular volume to the total water volume was significantly greater in scarred myocardium than in normal myocardium. Scarred myocardium contained massive residual capillaries and dilated vessels. Histological stains indicated the extensively discrete matrix deposition and lack of cellular structure in scarred myocardium. CONCLUSIONS: Collateral circulation formation and residual vessel effectively delivered CA into scarred myocardium. However, residual vessel without abnormal hyperpermeability allowed Gd

  17. Mast Cell-Mediated Mechanisms of Nociception

    Science.gov (United States)

    Aich, Anupam; Afrin, Lawrence B.; Gupta, Kalpna

    2015-01-01

    Mast cells are tissue-resident immune cells that release immuno-modulators, chemo-attractants, vasoactive compounds, neuropeptides and growth factors in response to allergens and pathogens constituting a first line of host defense. The neuroimmune interface of immune cells modulating synaptic responses has been of increasing interest, and mast cells have been proposed as key players in orchestrating inflammation-associated pain pathobiology due to their proximity to both vasculature and nerve fibers. Molecular underpinnings of mast cell-mediated pain can be disease-specific. Understanding such mechanisms is critical for developing disease-specific targeted therapeutics to improve analgesic outcomes. We review molecular mechanisms that may contribute to nociception in a disease-specific manner. PMID:26690128

  18. Curcumin in Cell Death Processes: A Challenge for CAM of Age-Related Pathologies

    Directory of Open Access Journals (Sweden)

    S. Salvioli

    2007-01-01

    Full Text Available Curcumin, the yellow pigment from the rhizoma of Curcuma longa, is a widely studied phytochemical which has a variety of biological activities: anti-inflammatory and anti-oxidative. In this review we discuss the biological mechanisms and possible clinical effects of curcumin treatment on cancer therapy, and neurodegenerative diseases such as Alzheimer's Disease, with particular attention to the cell death processes induced by curcumin. Since oxidative stress and inflammation are major determinants of the aging process, we also argue that curcumin can have a more general effect that slows down the rate of aging. Finally, the effects of curcumin can be described as xenohormetic, since it activates a sort of stress response in mammalian cells.

  19. A systems model for immune cell interactions unravels the mechanism of inflammation in human skin.

    Directory of Open Access Journals (Sweden)

    Najl V Valeyev

    Full Text Available Inflammation is characterized by altered cytokine levels produced by cell populations in a highly interdependent manner. To elucidate the mechanism of an inflammatory reaction, we have developed a mathematical model for immune cell interactions via the specific, dose-dependent cytokine production rates of cell populations. The model describes the criteria required for normal and pathological immune system responses and suggests that alterations in the cytokine production rates can lead to various stable levels which manifest themselves in different disease phenotypes. The model predicts that pairs of interacting immune cell populations can maintain homeostatic and elevated extracellular cytokine concentration levels, enabling them to operate as an immune system switch. The concept described here is developed in the context of psoriasis, an immune-mediated disease, but it can also offer mechanistic insights into other inflammatory pathologies as it explains how interactions between immune cell populations can lead to disease phenotypes.

  20. Mechanical regulation of mesenchymal stem cell differentiation.

    Science.gov (United States)

    Steward, Andrew J; Kelly, Daniel J

    2015-12-01

    Biophysical cues play a key role in directing the lineage commitment of mesenchymal stem cells or multipotent stromal cells (MSCs), but the mechanotransductive mechanisms at play are still not fully understood. This review article first describes the roles of both substrate mechanics (e.g. stiffness and topography) and extrinsic mechanical cues (e.g. fluid flow, compression, hydrostatic pressure, tension) on the differentiation of MSCs. A specific focus is placed on the role of such factors in regulating the osteogenic, chondrogenic, myogenic and adipogenic differentiation of MSCs. Next, the article focuses on the cellular components, specifically integrins, ion channels, focal adhesions and the cytoskeleton, hypothesized to be involved in MSC mechanotransduction. This review aims to illustrate the strides that have been made in elucidating how MSCs sense and respond to their mechanical environment, and also to identify areas where further research is needed.

  1. Mechanisms of cell transformation induced by polyomavirus

    Directory of Open Access Journals (Sweden)

    M.L.S. Oliveira

    1999-07-01

    Full Text Available Polyomavirus is a DNA tumor virus that induces a variety of tumors in mice. Its genome encodes three proteins, namely large T (LT, middle T (MT, and small T (ST antigens, that have been implicated in cell transformation and tumorigenesis. LT is associated with cell immortalization, whereas MT plays an essential role in cell transformation by binding to and activating several cytoplasmic proteins that participate in growth factor-induced mitogenic signal transduction to the nucleus. The use of different MT mutants has led to the identification of MT-binding proteins as well as analysis of their importance during cell transformation. Studying the molecular mechanisms of cell transformation by MT has contributed to a better understanding of cell cycle regulation and growth control.

  2. ETosis: A Microbicidal Mechanism beyond Cell Death

    Directory of Open Access Journals (Sweden)

    Anderson B. Guimarães-Costa

    2012-01-01

    Full Text Available Netosis is a recently described type of neutrophil death occurring with the release to the extracellular milieu of a lattice composed of DNA associated with histones and granular and cytoplasmic proteins. These webs, initially named neutrophil extracellular traps (NETs, ensnare and kill microorganisms. Similarly, other cell types, such as eosinophils, mast cells, and macrophages, can also dye by this mechanism; thus, it was renamed as ETosis, meaning death with release of extracellular traps (ETs. Here, we review the mechanism of NETosis/etosis, emphasizing its role in diseases caused by protozoan parasites, fungi, and viruses.

  3. NKG2D Mediates NK Cell Hyperresponsiveness and Influenza-Induced Pathologies in a Mouse Model of COPD

    OpenAIRE

    Wortham, Brian W.; Eppert, Bryan L.; Motz, Greg T.; Flury, Jennifer L.; Orozco-Levi, Mauricio; Hoebe, Kasper; Panos, Ralph J.; Maxfield, Melissa; Glasser, Stephan W.; Senft, Albert P; Raulet, David H.; Borchers, Michael T.

    2012-01-01

    Chronic obstructive pulmonary disease (COPD) is characterized by peribronchial and perivascular inflammation and largely irreversible airflow obstruction. Acute disease exacerbations, due frequently to viral infections, lead to enhanced disease symptoms and contribute to long-term progression of COPD pathology. Previously, we demonstrated that NK cells from cigarette smoke (CS)-exposed mice exhibit enhanced effector functions in response to stimulating cytokines or toll-like receptor ligands....

  4. Relevance of EGFR gene mutation with pathological features and prognosis in patients with non-small-cell lung carcinoma

    Institute of Scientific and Technical Information of China (English)

    Cheng-De; Wang; Xin-Rong; Wang; Chao-Yang; Wang; Yi-Jun; Tang; Ming-Wen; Hao

    2015-01-01

    Objective:To study the relevance of EGFR gene mutation with pathological features and prognosis in patients with non-small-cell lung carcinoma.Methods:A total of 297 patients from July 2009 to May 2013 were chosen as objects.EGFR gene mutation were detected with fluorescence quantitative PCR.Relevance of EGFR gene mutation with clinical and pathological features was analyzed,and the prognosis of EGFR- mutant-patients and that of EGFR- wide type-patients was compared.Results:In 297 patients.136(45.79%) showed EGFR gene mutation.EGFR gene mutation had no significant relevance with age.gender,smoking history,family history of cancer and clinical stage(P>0.05);there was significant relevance between EGFR gene mutation and blood type,pathologic types,differentiation and diameter of cancer(P<0.05).The difference between prognosis of EGFR- mutant-patients and that of EGFR- wide type-patients was statistical significance(P<0.05).Conclusions:EGFR gene mutation has significant relevance with pathological features,the prognosis of EGFRmutant-paticnts is better than that of EGFR- wide type-patients.

  5. Relevance ofEGFR gene mutation with pathological features and prognosis in patients with non-small-cell lung carcinoma

    Institute of Scientific and Technical Information of China (English)

    Cheng-De Wang; Xin-Rong Wang; Chao-Yang Wang; Yi-Jun Tang; Ming-Wen Hao

    2015-01-01

    Objective:To study the relevance ofEGFR gene mutation with pathological features and prognosis in patients with non-small-cell lung carcinoma.Methods: A total of 297 patients from July 2009 to May 2013 were chosen as objects.EGFRgene mutation were detected with fluorescence quantitative PCR. Relevance ofEGFR gene mutation with clinical and pathological features was analyzed, and the prognosis of EGFR- mutant-patients and that of EGFR- wide type-patients was compared.Results:In 297 patients, 136 (45.79%) showed EGFR gene mutation.EGFR gene mutation had no significant relevance with age, gender, smoking history, family history of cancer and clinical stage (P>0.05); there was significant relevance betweenEGFR gene mutation and blood type, pathologic types, differentiation and diameter of cancer (P<0.05). The difference between prognosis of EGFR- mutant-patients and that of EGFR- wide type-patients was statistical significance (P<0.05).Conclusions:EGFR gene mutation has significant relevance with pathological features, the prognosis of EGFR- mutant-patients is better than that of EGFR- wide type-patients.

  6. α-Synuclein: Experimental Pathology.

    Science.gov (United States)

    Hasegawa, Masato; Nonaka, Takashi; Masuda-Suzukake, Masami

    2016-01-01

    α-Synuclein, which is present as a small, soluble, cytosolic protein in healthy subjects, is converted to amyloid-like fibrils in diseases such as Parkinson's disease (PD), dementia with Lewy bodies (DLB), and multiple system atrophy (MSA). Bulk synthesis of purified α-synuclein has made it more convenient to study the nature of the normal protein and the mechanism of its conversion to an abnormal form in vitro and in vivo. Synthetic α-synuclein fibrils and pathological α-synuclein from diseased brains can act as triggers to convert normal α-synuclein to an abnormal form via prion-like mechanisms. In this article, we describe the experimental pathologies of α-synuclein both in vitro and in vivo in human and animal models. Prion-like spreading of abnormal α-synuclein from cell to cell can account for the progression of these α-synucleinopathies. PMID:27481772

  7. Cell Mechanosensitivity: Mechanical Properties and Interaction with Gravitational Field

    Directory of Open Access Journals (Sweden)

    I. V. Ogneva

    2013-01-01

    Full Text Available This paper addressed the possible mechanisms of primary reception of a mechanical stimulus by different cells. Data concerning the stiffness of muscle and nonmuscle cells as measured by atomic force microscopy are provided. The changes in the mechanical properties of cells that occur under changed external mechanical tension are presented, and the initial stages of mechanical signal transduction are considered. The possible mechanism of perception of different external mechanical signals by cells is suggested.

  8. Mechanically activated artificial cell by using microfluidics.

    Science.gov (United States)

    Ho, Kenneth K Y; Lee, Lap Man; Liu, Allen P

    2016-01-01

    All living organisms sense mechanical forces. Engineering mechanosensitive artificial cell through bottom-up in vitro reconstitution offers a way to understand how mixtures of macromolecules assemble and organize into a complex system that responds to forces. We use stable double emulsion droplets (aqueous/oil/aqueous) to prototype mechanosensitive artificial cells. In order to demonstrate mechanosensation in artificial cells, we develop a novel microfluidic device that is capable of trapping double emulsions into designated chambers, followed by compression and aspiration in a parallel manner. The microfluidic device is fabricated using multilayer soft lithography technology, and consists of a control layer and a deformable flow channel. Deflections of the PDMS membrane above the main microfluidic flow channels and trapping chamber array are independently regulated pneumatically by two sets of integrated microfluidic valves. We successfully compress and aspirate the double emulsions, which result in transient increase and permanent decrease in oil thickness, respectively. Finally, we demonstrate the influx of calcium ions as a response of our mechanically activated artificial cell through thinning of oil. The development of a microfluidic device to mechanically activate artificial cells creates new opportunities in force-activated synthetic biology.

  9. Mechanically activated artificial cell by using microfluidics

    Science.gov (United States)

    Ho, Kenneth K. Y.; Lee, Lap Man; Liu, Allen P.

    2016-01-01

    All living organisms sense mechanical forces. Engineering mechanosensitive artificial cell through bottom-up in vitro reconstitution offers a way to understand how mixtures of macromolecules assemble and organize into a complex system that responds to forces. We use stable double emulsion droplets (aqueous/oil/aqueous) to prototype mechanosensitive artificial cells. In order to demonstrate mechanosensation in artificial cells, we develop a novel microfluidic device that is capable of trapping double emulsions into designated chambers, followed by compression and aspiration in a parallel manner. The microfluidic device is fabricated using multilayer soft lithography technology, and consists of a control layer and a deformable flow channel. Deflections of the PDMS membrane above the main microfluidic flow channels and trapping chamber array are independently regulated pneumatically by two sets of integrated microfluidic valves. We successfully compress and aspirate the double emulsions, which result in transient increase and permanent decrease in oil thickness, respectively. Finally, we demonstrate the influx of calcium ions as a response of our mechanically activated artificial cell through thinning of oil. The development of a microfluidic device to mechanically activate artificial cells creates new opportunities in force-activated synthetic biology. PMID:27610921

  10. Myofiber-specific TEAD1 overexpression drives satellite cell hyperplasia and counters pathological effects of dystrophin deficiency

    Science.gov (United States)

    Southard, Sheryl; Kim, Ju-Ryoung; Low, SiewHui; Tsika, Richard W; Lepper, Christoph

    2016-01-01

    When unperturbed, somatic stem cells are poised to affect immediate tissue restoration upon trauma. Yet, little is known regarding the mechanistic basis controlling initial and homeostatic ‘scaling’ of stem cell pool sizes relative to their target tissues for effective regeneration. Here, we show that TEAD1-expressing skeletal muscle of transgenic mice features a dramatic hyperplasia of muscle stem cells (i.e. satellite cells, SCs) but surprisingly without affecting muscle tissue size. Super-numeral SCs attain a ‘normal’ quiescent state, accelerate regeneration, and maintain regenerative capacity over several injury-induced regeneration bouts. In dystrophic muscle, the TEAD1 transgene also ameliorated the pathology. We further demonstrate that hyperplastic SCs accumulate non-cell-autonomously via signal(s) from the TEAD1-expressing myofiber, suggesting that myofiber-specific TEAD1 overexpression activates a physiological signaling pathway(s) that determines initial and homeostatic SC pool size. We propose that TEAD1 and its downstream effectors are medically relevant targets for enhancing muscle regeneration and ameliorating muscle pathology. DOI: http://dx.doi.org/10.7554/eLife.15461.001 PMID:27725085

  11. Pathological stage after neoadjuvant chemoradiation and esophagectomy superiorly predicts survival in patients with esophageal squamous cell carcinoma

    International Nuclear Information System (INIS)

    Background and purpose: To assess the usefulness of pathological stage according to the 7th edition of the Union for International Cancer Control–American Joint Committee on Cancer (UICC–AJCC) as a prognostic tool in patients undergoing neoadjuvant chemoradiation followed by esophagectomy (trimodality therapy, TMT) for locally advanced esophageal squamous cell carcinoma. Material and methods: One hundred twenty-five eligible patients completing TMT were enrolled for analysis. The clinical (cTNM7) and pathological (ypTNM7) stage groups of their tumors were prospectively classified, and re-grouped by the 6th edition (ypTNM6). Survival was analyzed using the Kaplan–Meier method. The Cox proportional hazard model and the Akaike information criterion (AIC) were used to compare the performance of staging systems. Results: With a median follow-up of 24.6 months, 54 patients (43.2%) died. Forty patients (32%) achieved pathological complete remission (pCR). The median survival was 31.8 months. On multivariate analysis, ypTNM7 (but not pCR or pN) was the only independent factor affecting overall survival (p < 0.001). The ypTNM7 was superior to cTNM7 or ypTNM6 in predicting both overall and recurrence-free survival after TMT based on AIC values and Cox proportional hazard model analysis. Conclusions: In patients with locally advanced esophageal squamous cell carcinoma undergoing TMT, ypTNM7 is the best predictor of survival

  12. Pathological Role of Tonsillar B Cells in IgA Nephropathy

    Directory of Open Access Journals (Sweden)

    Yusuke Suzuki

    2011-01-01

    Full Text Available Although impaired immune regulation along the mucosa-bone marrow axis has been postulated to play an important role, the pathogenesis of IgA nephropathy (IgAN is unknown; thus, no disease-specific therapy for this disease exists. The therapeutic efficacy of tonsillectomy or tonsillectomy in combination with steroid pulse therapy for IgAN has been discussed. Although randomized control trials for these therapies are ongoing in Japan, the scientific rationale for these therapies remains obscure. It is now widely accepted that abnormally glycosylated IgA1 and its related immune complex (IC are probably key molecules for the pathogenesis, and are thus considered possible noninvasive biomarkers for this disease. Emerging evidence indicates that B cells in mucosal infections, particularly in tonsillitis, may produce the nephritogenic IgA. In this paper, we briefly summarize characteristics of the nephritogenic IgA/IgA IC, responsible B cells, and underlying mechanisms. This clinical and experimental information may provide important clues for a therapeutic rationale.

  13. An historical perspective on cell mechanics.

    Science.gov (United States)

    Pelling, Andrew E; Horton, Michael A

    2008-04-01

    The physical properties of the protoplasm have long been of interest, and today, several intricate methods, including atomic force microscopy, have been employed in studies of cellular mechanics. However, many current concepts and experimental approaches actually have their beginnings over 300 years ago. Unfortunately, these pioneering studies have been all but forgotten. In this paper, we have reviewed some of the early literature on cellular mechanics to place modern work within an historical framework. It is clear that with current nanoscience approaches, modern experiments employing cell indentation, manipulation, particle rheology and micro- or nano-needle poking are now quantifying mechanical properties which were only qualitatively described 100 years ago. Aside from the variety of approaches our predecessors have employed to understand cellular mechanics, we feel an understanding of the past will help to propel nanoscience into the future. As nanophysiology and nanomedicine are developing, we as a community should take time to consider the early roots of these fields. PMID:18064487

  14. Ultrastructural changes in aster yellows phytoplasma affected Limonium sinuatum Mill. plants II. Pathology of cortex parenchyma cells

    Directory of Open Access Journals (Sweden)

    Anna Rudzińska-Langwald

    2014-02-01

    Full Text Available In Limonium sinuatum Mill, plants with severe symptoms of aster yellows infection phytoplasmas were present not only in the phloem but also in some cortex parenchymas cells. These parenchyma cells were situated at some distance from the conducting bundles. The phytoplasmas were observed directly in parenchyma cells cytoplasm. The number of phytoplasmas present in each selected cell varies. The cells with a small number of phytoplasmas show little pathological changes compared with the unaffected cells of the same zone of the stem as well with the cells of healthy plants. The cells filled with a number of phytoplasmas had their protoplast very much changed. The vacuole was reduced and in the cytoplasm a reduction of the number of ribosomes was noted and regions of homogenous structure appeared. Mitochondria were moved in the direction of the tonoplast and plasma membrane. Compared to the cells unaffected by phytoplasma, the mitochondria were smaller and had an enlarged cristae internal space. The chloroplasts from affected cells had a very significant reduction in size and the tylacoids system had disappeared. The role of these changes for creating phytoplasma friendly enviroment is discused.

  15. Pathological Mobilization and Activities of Dendritic Cells in Tumor-Bearing Hosts: Challenges and Opportunities for Immunotherapy of Cancer

    Science.gov (United States)

    Tesone, Amelia J.; Svoronos, Nikolaos; Allegrezza, Michael J.; Conejo-Garcia, Jose R.

    2013-01-01

    A common characteristic of solid tumors is the pathological recruitment of immunosuppressive myeloid cells, which in certain tumors includes dendritic cells (DCs). DCs are of particular interest in the field of cancer immunotherapy because they induce potent and highly specific anti-tumor immune responses, particularly in the early phase of tumorigenesis. However, as tumors progress, these cells can be transformed into regulatory cells that contribute to an immunosuppressive microenvironment favoring tumor growth. Therefore, controlling DC phenotype has the potential to elicit effective anti-tumor responses while simultaneously weakening the tumor’s ability to protect itself from immune attack. This review focuses on the dual nature of DCs in the tumor microenvironment, the regulation of DC phenotype, and the prospect of modifying DCs in situ as a novel immunotherapeutic approach. PMID:24339824

  16. Mechanics and polarity in cell motility

    Science.gov (United States)

    Ambrosi, D.; Zanzottera, A.

    2016-09-01

    The motility of a fish keratocyte on a flat substrate exhibits two distinct regimes: the non-migrating and the migrating one. In both configurations the shape is fixed in time and, when the cell is moving, the velocity is constant in magnitude and direction. Transition from a stable configuration to the other one can be produced by a mechanical or chemotactic perturbation. In order to point out the mechanical nature of such a bistable behaviour, we focus on the actin dynamics inside the cell using a minimal mathematical model. While the protein diffusion, recruitment and segregation govern the polarization process, we show that the free actin mass balance, driven by diffusion, and the polymerized actin retrograde flow, regulated by the active stress, are sufficient ingredients to account for the motile bistability. The length and velocity of the cell are predicted on the basis of the parameters of the substrate and of the cell itself. The key physical ingredient of the theory is the exchange among actin phases at the edges of the cell, that plays a central role both in kinematics and in dynamics.

  17. An Important Method in the Investigation of Vascular Pathologies: Endothelial Cell Culture

    Directory of Open Access Journals (Sweden)

    Yusufhan Yazır

    2012-12-01

    Full Text Available Endothelial cells line the interior surface of blood vessels and form an interface between circulating blood in the lumen and the rest of the vessel wall. Endothelial cells are involved in many aspects of vascular biology, including barrier function, vasoconstriction, coagulation and inflamation. The endothelial cells in different organs have different functions and surface phenotype. These cells express prostoglandin-I2, platelet activating factor, collagen, endothelin-1, laminin, fibronectin and growth factors including platelet derived growth factor, fibroblast growth factor. İn the cell culture, cells can be isolated, maintened and proliferate in the laboratory conditions. The techniques of the cell culture have allowed scientists to use the cells in vitro for experimental studies, such as the production of vaccine, antibody and enzime, drug research, cell-cell interactions. Human umbilical vein endothelial cell is a good source for endothelial cell, because it is cheaper, easy to find and has the basic features of the normal endothelial cells.

  18. Cell shape, cytoskeletal mechanics, and cell cycle control in angiogenesis

    Science.gov (United States)

    Ingber, D. E.; Prusty, D.; Sun, Z.; Betensky, H.; Wang, N.

    1995-01-01

    Capillary endothelial cells can be switched between growth and differentiation by altering cell-extracellular matrix interactions and thereby, modulating cell shape. Studies were carried out to determine when cell shape exerts its growth-regulatory influence during cell cycle progression and to explore the role of cytoskeletal structure and mechanics in this control mechanism. When G0-synchronized cells were cultured in basic fibroblast growth factor (FGF)-containing defined medium on dishes coated with increasing densities of fibronectin or a synthetic integrin ligand (RGD-containing peptide), cell spreading, nuclear extension, and DNA synthesis all increased in parallel. To determine the minimum time cells must be adherent and spread on extracellular matrix (ECM) to gain entry into S phase, cells were removed with trypsin or induced to retract using cytochalasin D at different times after plating. Both approaches revealed that cells must remain extended for approximately 12-15 h and hence, most of G1, in order to enter S phase. After this restriction point was passed, normally 'anchorage-dependent' endothelial cells turned on DNA synthesis even when round and in suspension. The importance of actin-containing microfilaments in shape-dependent growth control was confirmed by culturing cells in the presence of cytochalasin D (25-1000 ng ml-1): dose-dependent inhibition of cell spreading, nuclear extension, and DNA synthesis resulted. In contrast, induction of microtubule disassembly using nocodazole had little effect on cell or nuclear spreading and only partially inhibited DNA synthesis. Interestingly, combination of nocodazole with a suboptimal dose of cytochalasin D (100 ng ml-1) resulted in potent inhibition of both spreading and growth, suggesting that microtubules are redundant structural elements which can provide critical load-bearing functions when microfilaments are partially compromised. Similar synergism between nocodazole and cytochalasin D was observed

  19. Cell Mechanosensitivity: Mechanical Properties and Interaction with Gravitational Field

    OpenAIRE

    I. V. Ogneva

    2013-01-01

    This paper addressed the possible mechanisms of primary reception of a mechanical stimulus by different cells. Data concerning the stiffness of muscle and nonmuscle cells as measured by atomic force microscopy are provided. The changes in the mechanical properties of cells that occur under changed external mechanical tension are presented, and the initial stages of mechanical signal transduction are considered. The possible mechanism of perception of different external mechanical signals by c...

  20. 18-F fluorodeoxyglucose uptake in positron emission tomography as a pathological grade predictor for renal clear cell carcinomas

    Energy Technology Data Exchange (ETDEWEB)

    Noda, Yoshifumi; Goshima, Satoshi; Kondo, Hiroshi; Watanabe, Haruo; Kawada, Hiroshi; Kawai, Nobuyuki; Tanahashi, Yukichi [Gifu University Hospital, Department of Radiology, Gifu (Japan); Kanematsu, Masayuki [Gifu University Hospital, Department of Radiology, Gifu (Japan); Gifu University Hospital, Department of Radiology Services, Gifu (Japan); Suzui, Natsuko [Gifu University Hospital, Department of Pathology, Gifu (Japan); Hirose, Yoshinobu [Osaka Medical College, Department of Pathology, Osaka (Japan); Matsunaga, Kengo [Kizawa Memorial Hospital, Department of Pathology, Minokamo (Japan); Nishibori, Hironori [Kizawa Memorial Hospital, Department of Radiology, Minokamo (Japan); Bae, Kyongtae T. [University of Pittsburgh Medical Center, Department of Radiology, Pittsburgh, PA (United States)

    2015-10-15

    To evaluate the usefulness of Fluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography (18-F FDG-PET/CT) in the prediction of Fuhrman pathological grades of renal clear cell carcinoma (cRCC). This retrospective study was approved by our institutional review board, and written informed consent was waived. Thirty-one patients with pathologically proven cRCC underwent 18-F FDG-PET/CT for tumour staging. Maximum standardized uptake value of cRCC (tumour SUV{sub max}) and mean SUV of the liver and spleen (liver and spleen SUV{sub mean}) were measured by two independent observers. Tumour SUV{sub max}, tumour-to-liver SUV ratio, and tumour-to-spleen SUV ratio were correlated with the pathological grades. Logistic analysis demonstrated that only the tumour-to-liver SUV ratio was a significant parameter for differentiating high-grade (Fuhrman grades 3 and 4) tumours from low-grade (Fuhrman grades 1 and 2) tumours (P = 0.007 and 0.010 for observers 1 and 2, respectively). Sensitivity, specificity, and positive and negative predictive values for detecting tumours of Fuhrman grades 3 and 4 were 64, 100, 100, and 77 %, respectively, for observer 1, and 79, 88, 85, and 83 %, respectively, for observer 2. The tumour-to-liver SUV ratio with 18-F FDG-PET/CT appeared to be a valuable imaging biomarker in the prediction of high-grade cRCC. (orig.)

  1. Mechanical properties of hepatocellular carcinoma cells

    Institute of Scientific and Technical Information of China (English)

    Gang Zhang; Mian Long; Zhe-Zhi Wu; Wei-Qun Yu

    2002-01-01

    of hepatocytes generallyincreased or tended to increase while those of HCC cellsdecreased. HTC cells with 72.1% ofG1 phase and 98. 9 % ofS phase were achieved and high K1, k2 value and low μvalue were the general characlteristics of HTC cells. G1phase cells had higher K1 value and lower tμ value than Sphase cells had, and G1 phase HTC cells had strongeradhesive forces [(275.9±232.8) x 10-10N] than S phase cells[(161.2± 120.4) x l0-10N, P<0.001).CONCLUSION: The difference in both the pattern and themagnitude of the effect of cytoskeletal perturbing agent onthe viscoelastic properties between HCC cells andhepatocytes may reflect differencss in the state of thecytusieleton structure and function and in the sensitivity toperturbing agent treatment between trinse two types of cells.Change in the viscoelastic properties of cancer cells mayaffect significantly tumor cell invasion and metastasis as wellas interactions between tumor cells and their micro-mechanical environments.

  2. [Basal cell carcinoma of the skin--biological behaviour of the tumor and a review of the most important molecular predictors of disease progression in pathological practice].

    Science.gov (United States)

    Bartos, V; Adamicová, K; Kullová, M; Péc, M

    2011-01-01

    Basal cell carcinoma of the skin is currently the most frequent malignancy in human population. Basal cell carcinoma represents a heterogeneous group of tumors with a variable clinical and morphological picture. Based on its biological behaviour, we generally differentiate between indolent (superficial and nodular) and aggressive type (infiltrative, micronodular, and metatypical) of basal cell carcinoma. Because of the different biological characteristics of these tumors, it is questionable whether they are a part of a continuous spectrum of carcinogenesis, starting with indolent and ending with aggressive forms, or they represent separate developmental lines. In the current clinical practice, there is an increasing demand for identification of tumors that are prognostically more adverse and their impact on the overall health status of patients is more serious. Recent advances in pathology and molecular medicine allow identification of various biomarkers from tumor tissue that are significantly involved in the mechanisms of malignant cell transformation. Detection of these biomarkers is of great importance in predicting further clinical behaviour of the cancer. The authors of the paper present basic information about biological behaviour of cutaneous basal cell carcinoma and provide an overview of the most important biomarkers that influence the clinical outcome and disease progression and are detectable through a routine biopsy tissue examination. It is now necessary to search for novel histological and molecular parameters that, in the future, could have a prognostic value in diagnostic and therapeutic process of this disorder. PMID:21542271

  3. Molecular Pathways Regulating Macrovascular Pathology and Vascular Smooth Muscle Cells Phenotype in Type 2 Diabetes

    Directory of Open Access Journals (Sweden)

    Sara Casella

    2015-10-01

    Full Text Available Type 2 diabetes mellitus (T2DM is a disease reaching a pandemic proportion in developed countries and a major risk factor for almost all cardiovascular diseases and their adverse clinical manifestations. T2DM leads to several macrovascular and microvascular alterations that influence the progression of cardiovascular diseases. Vascular smooth muscle cells (VSMCs are fundamental players in macrovascular alterations of T2DM patients. VSMCs display phenotypic and functional alterations that reflect an altered intracellular biomolecular scenario of great vessels of T2DM patients. Hyperglycemia itself and through intraparietal accumulation of advanced glycation-end products (AGEs activate different pathways, in particular nuclear factor-κB and MAPKs, while insulin and insulin growth-factor receptors (IGFR are implicated in the activation of Akt and extracellular-signal-regulated kinases (ERK 1/2. Nuclear factor-κB is also responsible of increased susceptibility of VSMCs to pro-apoptotic stimuli. Down-regulation of insulin growth-factor 1 receptors (IGFR-1R activity in diabetic vessels also influences negatively miR-133a levels, so increasing apoptotic susceptibility of VSMCs. Alterations of those bimolecular pathways and related genes associate to the prevalence of a synthetic phenotype of VSMCs induces extracellular matrix alterations of great vessels. A better knowledge of those biomolecular pathways and related genes in VSMCs will help to understand the mechanisms leading to macrovascular alterations in T2DM patients and to suggest new targeted therapies.

  4. Novel optical methodologies in studying mechanical signal transduction in mammalian cells

    Science.gov (United States)

    Stamatas, G. N.; McIntire, L. V.

    1999-01-01

    For the last 3 decades evidence has been accumulating that some types of mammalian cells respond to their mechanically active environment by altering their morphology, growth rate, and metabolism. The study of such responses is very important in understanding, physiological and pathological conditions ranging from bone formation to atherosclerosis. Obtaining this knowledge has been the goal for an active research area in bioengineering termed cell mechanotransduction. The advancement of optical methodologies used in cell biology research has given the tools to elucidate cellular mechanisms that would otherwise be impossible to visualize. Combined with molecular biology techniques, they give engineers invaluable tools in understanding the chemical pathways involved in mechanotransduction. Herein we briefly review the current knowledge on mechanical signal transduction in mammalian cells, focusing on the application of novel optical techniques in the ongoing research.

  5. Quantitation and renewal of alveolar and bronchiolar cell populations of rat lungs. Changes during some pathological processes

    International Nuclear Information System (INIS)

    The various cells of alveolar and bronchiolar tissues of rat lungs were studied qualitatively and quantitatively. In physiological conditions, the renewal rate of the cell populations is low and the frequency of the various cell types is constant. This stability, especially at the level of the alveolar tissue, was also found during the latency period and the development of radiation-induced lung cancers. A particular cellular population was demonstrated: marginated leukocyte pool at the level of the pulmonary circulation. This pool was different both qualitatively and quantitatively from the leukocytes of the systemic circulation and, in physiological conditions, behaved as a cellular reservoir of monocytes chiefly re-distributed according to the body needs. In pathological conditions, its fast migration contributed to the defence of the alveolar medium. A quantitative study of the renewal of alveolar macrophages showed that under 1 p. cent of the marginated leukocyte pool is used daily to keep up this population. This fraction undergoes a maturation stage by cellular division within the endoalveolar medium. In some pathological conditions, this division can be completely inhibited

  6. Adrenomedullin promotes differentiation of oligodendrocyte precursor cells into myelin-basic-protein expressing oligodendrocytes under pathological conditions in vitro.

    Science.gov (United States)

    Maki, Takakuni; Takahashi, Yoko; Miyamoto, Nobukazu; Liang, Anna C; Ihara, Masafumi; Lo, Eng H; Arai, Ken

    2015-07-01

    Oligodendrocytes, which are the main cell type in cerebral white matter, are generated from their precursor cells (oligodendrocyte precursor cells: OPCs). However, the differentiation from OPCs to oligodendrocytes is disturbed under stressed conditions. Therefore, drugs that can improve oligodendrocyte regeneration may be effective for white matter-related diseases. Here we show that a vasoactive peptide adrenomedullin (AM) promotes the in vitro differentiation of OPCs under pathological conditions. Primary OPCs were prepared from neonatal rat brains, and differentiated into myelin-basic-protein expressing oligodendrocytes over time. This in vitro OPC differentiation was inhibited by prolonged chemical hypoxic stress induced by non-lethal CoCl(2) treatment. However, AM promoted the OPC differentiation under the hypoxic stress conditions, and the AM receptor antagonist AM(22-52) canceled the AM-induced OPC differentiation. In addition, AM treatment increased the phosphorylation level of Akt in OPC cultures, and correspondingly, the PI3K/Akt inhibitor LY294002 blocked the AM-induced OPC differentiation. Taken together, AM treatment rescued OPC maturation under pathological conditions via an AM-receptor-PI3K/Akt pathway. Oligodendrocytes play critical roles in white matter by forming myelin sheath. Therefore, AM signaling may be a promising therapeutic target to boost oligodendrocyte regeneration in CNS disorders.

  7. Adrenomedullin promotes differentiation of oligodendrocyte precursor cells into myelin-basic-protein expressing oligodendrocytes under pathological conditions in vitro

    Directory of Open Access Journals (Sweden)

    Takakuni Maki

    2015-07-01

    Full Text Available Oligodendrocytes, which are the main cell type in cerebral white matter, are generated from their precursor cells (oligodendrocyte precursor cells: OPCs. However, the differentiation from OPCs to oligodendrocytes is disturbed under stressed conditions. Therefore, drugs that can improve oligodendrocyte regeneration may be effective for white matter-related diseases. Here we show that a vasoactive peptide adrenomedullin (AM promotes the in vitro differentiation of OPCs under pathological conditions. Primary OPCs were prepared from neonatal rat brains, and differentiated into myelin-basic-protein expressing oligodendrocytes over time. This in vitro OPC differentiation was inhibited by prolonged chemical hypoxic stress induced by non-lethal CoCl2 treatment. However, AM promoted the OPC differentiation under the hypoxic stress conditions, and the AM receptor antagonist AM22–52 canceled the AM-induced OPC differentiation. In addition, AM treatment increased the phosphorylation level of Akt in OPC cultures, and correspondingly, the PI3K/Akt inhibitor LY294002 blocked the AM-induced OPC differentiation. Taken together, AM treatment rescued OPC maturation under pathological conditions via an AM-receptor-PI3K/Akt pathway. Oligodendrocytes play critical roles in white matter by forming myelin sheath. Therefore, AM signaling may be a promising therapeutic target to boost oligodendrocyte regeneration in CNS disorders.

  8. Adrenomedullin promotes differentiation of oligodendrocyte precursor cells into myelin-basic-protein expressing oligodendrocytes under pathological conditions in vitro.

    Science.gov (United States)

    Maki, Takakuni; Takahashi, Yoko; Miyamoto, Nobukazu; Liang, Anna C; Ihara, Masafumi; Lo, Eng H; Arai, Ken

    2015-07-01

    Oligodendrocytes, which are the main cell type in cerebral white matter, are generated from their precursor cells (oligodendrocyte precursor cells: OPCs). However, the differentiation from OPCs to oligodendrocytes is disturbed under stressed conditions. Therefore, drugs that can improve oligodendrocyte regeneration may be effective for white matter-related diseases. Here we show that a vasoactive peptide adrenomedullin (AM) promotes the in vitro differentiation of OPCs under pathological conditions. Primary OPCs were prepared from neonatal rat brains, and differentiated into myelin-basic-protein expressing oligodendrocytes over time. This in vitro OPC differentiation was inhibited by prolonged chemical hypoxic stress induced by non-lethal CoCl(2) treatment. However, AM promoted the OPC differentiation under the hypoxic stress conditions, and the AM receptor antagonist AM(22-52) canceled the AM-induced OPC differentiation. In addition, AM treatment increased the phosphorylation level of Akt in OPC cultures, and correspondingly, the PI3K/Akt inhibitor LY294002 blocked the AM-induced OPC differentiation. Taken together, AM treatment rescued OPC maturation under pathological conditions via an AM-receptor-PI3K/Akt pathway. Oligodendrocytes play critical roles in white matter by forming myelin sheath. Therefore, AM signaling may be a promising therapeutic target to boost oligodendrocyte regeneration in CNS disorders. PMID:26002630

  9. Efficient Assessment of Developmental, Surgical and Pathological Lymphangiogenesis Using a Lymphatic Reporter Mouse and Its Embryonic Stem Cells

    Science.gov (United States)

    Jung, Wonhyuek; Seong, Young Jin; Park, Eunkyung; Bramos, Athanasios; Kim, Kyu Eui; Lee, Sunju; Daghlian, George; Seo, Jung In; Choi, Inho; Choi, In-Seon; Koh, Chester J.; Kobielak, Agnieszka; Ying, Qi-Long; Johnson, Maxwell; Gardner, Daniel; Wong, Alex K.; Choi, Dongwon; Hong, Young-Kwon

    2016-01-01

    Several lymphatic reporter mouse lines have recently been developed to significantly improve imaging of lymphatic vessels. Nonetheless, the usage of direct visualization of lymphatic vessels has not been fully explored and documented. Here, we characterized a new Prox1-tdTomato transgenic lymphatic reporter mouse line, and demonstrated how this animal tool enables the researchers to efficiently assess developmental, surgical and pathological lymphangiogenesis by direct visualization of lymphatic vessels. Moreover, we have derived embryonic stem cells from this reporter line, and successfully differentiated them into lymphatic vessels in vivo. In conclusion, these experimental tools and techniques will help advance lymphatic research. PMID:27280889

  10. CT features on increased cerebral vascular density and its pathological mechanism in patients with cyanotic congenital disease

    International Nuclear Information System (INIS)

    Objective: To investigate CT features on increased cerebral vascular density and its pathological mechanism in patients with cyanotic congenital heart disease (CCHD). Methods: Preoperative brain CT scan and clinical data in 82 patients suffering from CCHD were analyzed. According to the increased levels of vascular density, patients were divided into 4 groups: normal, mild, moderate and severe. Relationships between the increased levels of vascular density and Hb, RBC, HCT, as well as the degree of cyanosis,were studied. AVONA was carried out to test blood CT value of cerebral sinuses, Hb, RBC and HCT in different groups. Descriptive analysis and linear regression were adopted to study the correlation between blood CT value and Hb concentration. The relationship of increased vascular density to degrees of cyanosis was analysed by Spearman. Results: Among 82 patients, 12 patients (14.6%) were found in the group of normal vascular density and 70 patients (85.4%) in the increased vascular density group. Among 70 patients with increased vascular density, 22 patients (26.8% ) with (55.4 ± 2.6) HU, (169 ±6)g/L of Hb, (5.8 ±0.3) × 1012/L of RBC and 0.51 ±0.03 of HCT, 29 patients (35.4%) with (61.3 ± 2.9) HU, (209 ± 15 ) g/L, (7.1 ± 0.4) × 1012/L, 0.66 ± 0.06 and 19 patients (23.2%) with (68.8 ± 4.2) HU, (242 ± 23) g/L, (8.3 ± 0.9) × 1012/L, 0.78 ± 0.08 were observed in the mild,moderate and severe group,respectively. There were significant differences in distribution of blood CT value (HU), Hb, RBC and HCT in different groups (F=163.263, 134.703, 120.974, 136.541; P<0.01). Blood CT value was positively correlated with Hb concentration (r=0.98, P<0.01). Vascular density was also positively correlated with the degree of cyanosis (r=0.86, P<0.01). Conclusions: Cerebral vascular density of patients suffering from CCHD presented different levels of increases based on CT scan results due to rise of RBC stimulated by anoxia. The increased level of vascular density

  11. Epidermal stem cells - role in normal, wounded and pathological psoriatic and cancer skin

    DEFF Research Database (Denmark)

    Kamstrup, M.; Faurschou, A.; Gniadecki, R.;

    2008-01-01

    In this review we focus on epidermal stem cells in the normal regeneration of the skin as well as in wounded and psoriatic skin. Furthermore, we discuss current data supporting the idea of cancer stem cells in the pathogenesis of skin carcinoma and malignant melanoma. Epidermal stem cells present...... or transit amplifying cells constitute a primary pathogenetic factor in the epidermal hyperproliferation seen in psoriasis. In cutaneous malignancies mounting evidence supports a stem cell origin in skin carcinoma and malignant melanoma and a possible existence of cancer stem cells Udgivelsesdato: 2008/5...

  12. Osler's pathology.

    Science.gov (United States)

    Pai, S A

    2000-12-01

    Sir William Osler, one of the giants of clinical medicine, had his initial training as a pathologist. He was one of the physicians responsible for the impact that autopsies have had on medicine. He also contributed to the development of laboratory medicine. Osler made significant discoveries in anatomic pathology and hematology. His expertise was restricted not just to human pathology, but also to veterinary pathology. His mentors played a fundamental role in his achievements in academics.

  13. Analysis of Alterations in Morphologic Characteristics of Mesenchymal Stem Cells by Mechanical Stimulation during Differentiation into Smooth Muscle Cells

    Directory of Open Access Journals (Sweden)

    Mohammad Ali Shokrgozar

    2010-01-01

    Full Text Available Objective: Mesenchymal stem cells (MSCs can be expanded and differentiated intomany mature cell types including smooth muscle cells (SMCs. In addition to growth factor,cyclic stretch contributes to differentiation of stem cells. Mechanical stimuli are criticalto morphological changes, development, regeneration, differentiation and pathology ofmesenchymal tissues. The aim of this study is to investigate effects of cyclic stretch withdiffering amplitudes on morphology and differentiation of mesenchymal stem cells.Materials and Methods: Mesenchymal stem cells are extracted from human bone marrow.Cells are cultured on silicone membrane and exposed to cyclic stretch by a custommade device. Cellular images are captured before and after tests. Effects of 5% and 15%uniaxial strain with 1Hz frequency and 1-8 hour durations on morphology of human mesenchymalstem cells are investigated. It is assumed that environmental factors such asmechanical loading regulate MSCs differentiation to SMCs. Fractal analysis is used toquantify alterations in cellular morphology. An image processing method with a designedcode is used for evaluation of fractal dimension parameter.Results: Results demonstrate statistically significant change in cell morphology due tomechanical stretch. By elevation of strain amplitude and number of load cycles, fractaldimensions of cell images decrease. Such decrease is equivalent to alignment of cells bymechanical stimulus. Cells are differentiated to SMCs purely by cyclic stretch. The initiationand rate of differentiation depend on mechanical conditions.Conclusion: To produce functional SMCs for engineered tissues, MSCs can be exposed to uniaxialcyclic stretch. The functionality of differentiated SMCs depends on loading conditions.

  14. Particle-rich cytoplasmic structure (PaCS): identification, natural history, role in cell biology and pathology.

    Science.gov (United States)

    Solcia, Enrico; Sommi, Patrizia; Necchi, Vittorio; Vitali, Agostina; Manca, Rachele; Ricci, Vittorio

    2014-09-22

    Cytoplasmic structures showing a selective concentration of both polyubiquitinated proteins and proteasome have been described in various epithelial, hematopoietic, mesenchymal and neural cells in vitro or in fetal tissues, as well as in chronically-infected, mutated preneoplastic and neoplastic tissues. These cytoplasmic structures differ from other ubiquitin-reactive cytoplasmic bodies, like sequestosomes, aggresome-like-induced structures in dendritic cells (DALIS)/non-dendritic cells (ALIS) and aggresomes in showing distinctive ultrastructural organization (particle-rich cytoplasmic structure or PaCS), a cytochemical pattern and a functional profile. Their formation can be induced in vitro in dendritic or natural killer cells by trophic factors and interleukin treatment. They originate in close connection with ribosomes, while, as a result of their growth, the cytoskeleton and other surrounding organelles are usually dislocated outside their core. Interestingly, these particulate cytoplasmic structures are often found to fill cytoplasmic blebs forming proteasome- and polyubiquitinated protein-discharging vesicles, called ectosomes, which are found to detach from the cell and freely float in the extracellular space. To clearly point out the importance of the polyubiquitinated proteins and proteasome containing cytoplasmic structures, their role in cell biology and pathology has been carefully analyzed.

  15. Pathological clavicular fracture as ifrst presentation of renal cell carcinoma:a case report and literature review

    Institute of Scientific and Technical Information of China (English)

    Yan Kong; Jin Wang; Huan Li; Peng Guo; Jian-Fa Xu; He-Lin Feng

    2015-01-01

    Renal cell carcinoma (RCC) accounts for approximately 3%of all cancer cases. RCCs usually metastasize to the lungs, bones, liver, or brain. Only<1%of patients with bone metastases manifested clavicular RCC metastases. hTus, clavicular metastasis as the initial presentation of RCC is extremely rare. We report a patient with RCC metastasis to the letf clavicle, which was ifrst presented with pain caused by a pathological fracture. Magnetic resonance image revealed a renal tumor, and technetium-99m–methylene diphosphonate bone scintigraphy showed multiple osseous metastases. The patient eventually underwent surgery to remove the lateral end of the letf clavicle and right kidney. Histopathology revealed renal tumor and clear cell carcinoma in the clavicle. Finally, we review 17 cases of clavicular metastases originating from different malignancies.

  16. Reversibility of the Pathological Changes in the Follicular Dendritic Cell Network with Treatment of HIV-1 Infection

    Science.gov (United States)

    Zhang, Zhi-Qiang; Schuler, Troy; Cavert, Winston; Notermans, Daan W.; Gebhard, Kristin; Henry, Keith; Havlir, Diane V.; Gunthard, Huldrych F.; Wong, Joseph K.; Little, Susan; Feinberg, Mark B.; Polis, Michael A.; Schrager, Lewis K.; Schacker, Timothy W.; Richman, Douglas D.; Corey, Lawrence; Danner, Sven A.; Haase, Ashley T.

    1999-04-01

    Over the course of HIV-1 infection, the lymphoid follicles where the humoral immune response is generated initially increase in size and number and then progressively involute. In advanced disease, the network of the processes of follicular dendritic cells (FDCs) that serve as antigen respositories and anatomical substrate for B and T cells and antigen to interact is destroyed, contributing to the breakdown of the immune system. Because destruction of FDCs is associated with deposition of HIV-1, and much of the virus can be cleared from the network with antiretroviral therapy, we investigated the reversibility of damage. We measured the immunohistochemically stainable FDC compartment by quantitative image analysis, and we documented changes in this compartment at different stages of disease. We show that treatment, initiated even at advanced stages of HIV-1 disease, can slowly reverse pathological changes in the FDC network.

  17. 病理性赌博的发生机制研究综述%A Review on the Mechanism of Pathological Gambling

    Institute of Scientific and Technical Information of China (English)

    叶绿; 马红宇; 史文文; 李娜; 王斌

    2013-01-01

    Pathological gambling refers to a gambling behavior conducted by the individuals who can't control the impulse and then addict to gamble,which adversely affects individuals,families and society.On the basis of referring to relevant literatures,it was found that the mechanism of pathological gambling may be attributed to the interaction of three factors,including biologic,psychological and social facets.Future research should pay attention to the building of the causal model of pathological gambling,and strengthening the study of pathological gambling intervention and prevention.%病理性赌博是指个体难以控制赌博冲动,使其持久地沉溺于赌博中,以致个人、家庭和社会受到不良影响的赌博行为.本研究在参阅病理性赌博和其它行为成瘾相关文献的基础上,对病理性赌博的发生机制进行探讨,指出其是生物、心理和社会因素共同作用的结果.未来研究应注重构建病理性赌博的成因模型、加强病理性赌博的干预和预防研究.

  18. Concurrent sickle cell anemia and alpha-thalassemia. Effect on pathological properties of sickle erythrocytes.

    OpenAIRE

    Embury, S H; Clark, M R; Monroy, G; Mohandas, N

    1984-01-01

    The concurrence of sickle cell anemia and alpha-thalassemia results in less severe hemolytic anemia apparently as a result of reduced intraerythrocytic concentration of hemoglobin S and its retarded polymerization. We have evaluated the effect of alpha-globin gene number on several interrelated properties of sickle erythrocytes (RBC) that are expected to correlate with the hemolytic and rheologic consequences of sickle cell disease. The irreversibly sickled cell number, proportion of very den...

  19. Combination of fluid and solid mechanical stresses contribute to cell death and detachment in a microfluidic alveolar model.

    Science.gov (United States)

    Douville, Nicholas J; Zamankhan, Parsa; Tung, Yi-Chung; Li, Ran; Vaughan, Benjamin L; Tai, Cheng-Feng; White, Joshua; Christensen, Paul J; Grotberg, James B; Takayama, Shuichi

    2011-02-21

    Studies using this micro-system demonstrated significant morphological differences between alveolar epithelial cells (transformed human alveolar epithelial cell line, A549 and primary murine alveolar epithelial cells, AECs) exposed to combination of solid mechanical and surface-tension stresses (cyclic propagation of air-liquid interface and wall stretch) compared to cell populations exposed solely to cyclic stretch. We have also measured significant differences in both cell death and cell detachment rates in cell monolayers experiencing combination of stresses. This research describes new tools for studying the combined effects of fluid mechanical and solid mechanical stress on alveolar cells. It also highlights the role that surface tension forces may play in the development of clinical pathology, especially under conditions of surfactant dysfunction. The results support the need for further research and improved understanding on techniques to reduce and eliminate fluid stresses in clinical settings. PMID:21152526

  20. Dynamic simulation of red blood cell metabolism and its application to the analysis of a pathological condition

    Directory of Open Access Journals (Sweden)

    Kinoshita Ayako

    2005-05-01

    Full Text Available Abstract Background Cell simulation, which aims to predict the complex and dynamic behavior of living cells, is becoming a valuable tool. In silico models of human red blood cell (RBC metabolism have been developed by several laboratories. An RBC model using the E-Cell simulation system has been developed. This prototype model consists of three major metabolic pathways, namely, the glycolytic pathway, the pentose phosphate pathway and the nucleotide metabolic pathway. Like the previous model by Joshi and Palsson, it also models physical effects such as osmotic balance. This model was used here to reconstruct the pathology arising from hereditary glucose-6-phosphate dehydrogenase (G6PD deficiency, which is the most common deficiency in human RBC. Results Since the prototype model could not reproduce the state of G6PD deficiency, the model was modified to include a pathway for de novo glutathione synthesis and a glutathione disulfide (GSSG export system. The de novo glutathione (GSH synthesis pathway was found to compensate partially for the lowered GSH concentrations resulting from G6PD deficiency, with the result that GSSG could be maintained at a very low concentration due to the active export system. Conclusion The results of the simulation were consistent with the estimated situation of real G6PD-deficient cells. These results suggest that the de novo glutathione synthesis pathway and the GSSG export system play an important role in alleviating the consequences of G6PD deficiency.

  1. Mechanical behavior of open cell aluminum foams

    Science.gov (United States)

    Zhou, Jikou

    Open cell metallic foams are relatively new materials with increasingly applications due to their attractive combinations of physical, chemical, mechanical and optical properties. Since plastic deformation in the struts involves dislocation motion, dislocation slip bands are used to track the initiation/propagation and locations of plastic deformation in individual struts. We find that the onset of plastic deformation in struts is far beyond the observable strut/cell shape changes, and both plastic bending and buckling are strut deformation modes. To measure the strut mechanical properties, an existing micro-scale tensile tester was updated to test the individual struts extracted from foams using electro-discharged machining. The micro-tensile testing results show that the foam struts are typically more ductile and one time stronger than the corresponding fully dense alloy. To integrate the measured strut and foam properties, a four-strut structure unit is identified as a structural representative of the open cell foam structure. Based on the observed strut deformation modes, mechanics analysis is performed on the structure unit to predict the foam stiffness and strength. The predictions are in good agreement with the measured data, suggesting the significance of the studies on the foam strut properties and deformation. This model also predicts the bounds of the foam strengths. Under cyclic compression, foams fail due to damage accumulation in individual struts, in which surface cracks initiate and grow. At low stress levels, surface cracks are formed in multiple struts that are distributed across the foam block. This results in an abrupt strain jump due to the crush of foam block, upon foam failure. To meet applications requirements, open cell aluminum foams are usually annealed or strengthened. The studies are carried out in the foams in the as-fabricated (F), annealed (O) and T6-strengthed (T6) conditions. We find that annealing and T6 strengthening

  2. Cerebral transplantation of encapsulated mesenchymal stem cells improves cellular pathology after experimental traumatic brain injury

    DEFF Research Database (Denmark)

    Heile, Anna M B; Wallrapp, Christine; Klinge, Petra M;

    2009-01-01

    PURPOSE: "Naked" human mesenchymal stem cells (MSC) are neuro-protective in experimental brain injury (TBI). In a controlled cortical impact (CCI) rat model, we investigated whether encapsulated MSC (eMSC) act similarly, and whether efficacy is augmented using cells transfected to produce the neu...

  3. Clinical and pathological features of testicular diffuse large B-cell lymphoma : a heterogeneous disease

    NARCIS (Netherlands)

    Kuper-Hommel, Marion J. J.; Janssen-Heijnen, Maryska L. G.; Vreugdenhil, Gerard; Krol, Augustinus D. G.; Kluin-Nelemans, Hanneke C.; Coebergh, Jan-Willem W.; van Krieken, J. Han J. M.

    2012-01-01

    Most testicular lymphomas are of diffuse large B-cell (DLBCL) type with an outcome inferior to nodal DLBCL. Within an apparently homogeneous group of testicular DLBCLs, small cell components, plasmacytoid differentiation and lymphoepithelial lesions (LELs), features of extranodal marginal zone lymph

  4. Tissue microarrays in pathological examination of apoptotic acinar cells induced by dexamethasone in the pancreas of rats with severe acute pancreatitis

    Institute of Scientific and Technical Information of China (English)

    Xi-Ping Zhang; Hua Tian; Bei Lu; Li Chen; Ru-Jun Xu; Ke-Yi Wang; Zhi-Wei Wang; Qi-Hui Cheng; Hai-Ping Shen

    2007-01-01

    BACKGROUND:The good therapeutic effects of large dose of dexamethasone on severe acute pancreatitis (SAP) patients have been proved. This study was designed to investigate the inlfuence of dexamethasone on apoptosis of acinar cells in the pancreas of rats with SAP and the protein expression of the apoptosis-regulating genes Bax and Bcl-2. METHODS: Ninety Sprague-Dawley rats with SAP were randomly divided into a model group and a dexamethasone treated group (45 rats in each group), and another 45 rats formed the sham operation group. Survival rates were calculated and gross pathological changes in the pancreas of each group were observed under a light microscope 3, 6 and 12 hours after operation. Tissue microarray technology was applied to prepare pancreatic tissue sections. The changes in Bax and Bcl-2 protein expression levels of pancreatic tissues from each group were assessed by immunohistochemical staining, and TUNEL staining was used to evaluate changes in apoptosis index. RESULTS: The model and treated groups did not differ in mortality at each time point. The pathological score for the pancreas in the treated group was signiifcantly lower than that in the model group at 3 and 6 hours. The positive rates of Bax protein expression in the head and tail of the pancreas in the treated group at all time points were all markedly higher than those of the model group. The positive rate of Bcl-2 protein expression in the head of the pancreas in the treated group was signiifcantly higher than that of the model group at 3 hours. TUNEL staining showed that the pancreas head and tail apoptosis indices of the treated group were markedly higher than those of the model group after 6 hours. CONCLUSIONS: Apoptosis may be a protective response to pancreatic cell injury. The mechanism of action of dexamethasone in treating SAP may be related to the apoptosis of acinar cells in the pancreas induced by apoptosis-regulating genes such as Bax and Bcl-2. The advantages of tissue

  5. [Mast cells, their adenosine receptors and reactive oxygen species in chronic inflammatory pathologies of childhood].

    Science.gov (United States)

    Renke, Joanna; Popadiuk, Stefan; Wozniak, Michał; Szlagatys-Sidorkiewicz, Agnieszka; Hansdorfer-Korzon, Rita

    2006-01-01

    Mast cells were described by Erhlich at the end of XIX-th century. Their role was deeply investigated in asthma and allergy. The massive degranulation of mast cells in allergy can lead to anaphylactic shock. Recently, mast cells have been recognized again as a very interesting topic for investigation, due to their possible role in chronic inflammation. Moreover, through adenosine receptors, mast cells can be activated or inactivated. That is why these cells are regarded as a potential target of new drugs. It has been reported, that mast cells generate intracellular reactive oxygen species (ROS) in response to stimulation with divergent physiologically relevant stimulants. The intensification of ROS production may be measured by the level of carbonyl groups, as a marker of protein peroxidation. However, the role of mast cells in other than asthma diseases with chronic inflammation needs further investigation. It was found out that the information about mast cell distribution in colonic mucosa may serve as help in differentiation between inflammatory bowel disease and collagenous colitis. Moreover, its accumulation in focal active gastritis was confirmed in patients with Crohn's disease. An important role in regulation of inflammatory process seems to be reserved for adenosine receptors present on mastocytes. The activation of mast cells through the adenosine receptor is connected with 11-8 release, which stimulate the migration of leukocytes and oxidation reactions. The detection of mast cells in tissues should not be limited only to the simple histologic examination. It should be completed by the detection of products of degranulation, e.g. tryptase. This is the way to find out their actual function and state of activation. PMID:17203808

  6. Ovarian Germline Stem Cells (OGSCs and the Hippo Signaling Pathway Association with Physiological and Pathological Ovarian Aging in Mice

    Directory of Open Access Journals (Sweden)

    Jia Li

    2015-07-01

    Full Text Available Background: The Hippo signaling pathway plays fundamental roles in stem cell maintenance in a variety of tissues and has thus implications for stem cell biology. Key components of this recently discovered pathway have been shown to be associated with primordial follicle activation. However, whether the Hippo signaling pathway plays a role in the development of Ovarian Germline Stem Cells (OGSCs during physiological and pathological ovarian aging in mice is unknown. Methods: Mice at the age of 7 days (7D, or of 2, 10, or 20 months (2M, 10M, 20M and mice at 2M treated with TPT and CY/BUS drugs were selected as physiological and pathological ovarian aging models, respectively. Immunohistochemistry was used to assess the development of follicles, and the co-localization of genes characteristic of OGSCs with MST1, LATS2 and YAP1 was assessed by immunofluorescence, western blotting and real-time PCR methods. Results: The Hippo signal pathway and MVH/OCT4 genes were co-expressed in the mouse ovarian cortex. The level and co-localization of LATS2, MST1, MVH, and OCT4 were significantly decreased with increased age, but YAP1 was more prevalent in the mouse ovarian cortex of 2M mice than 7D mice and was not observed in 20M mice. Furthermore, YAP1, MVH, and OCT4 were gradually decreased after TPT and CY/BUS treatment, and LATS2 mRNA and protein up-regulation persisted in TPT- and CY/BUS-treated mice. However, the expression of MST1 was lower in the TPT and CY/BUS groups compared with the control group. In addition, pYAP1 protein showed the highest expression in the ovarian cortexes of 7D mice compared with 20M mice, and the value of pYAP1/YAP1 decreased from 7D to 20M. Moreover, pYAP1 decreased in the TPT- and CY/BUS-treated groups, but the value of pYAP1/YAP1 increased in these groups. Conclusion: Taken together, our results show that the Hippo signaling pathway is associated with the changes that take place in OGSCs during physiological and pathological

  7. Pathological Assessment of Rectal Cancer after Neoadjuvant Chemoradiotherapy: Distribution of Residual Cancer Cells and Accuracy of Biopsy

    Science.gov (United States)

    Xiao, Lin; Yu, Xin; Deng, Wenjing; Feng, Huixia; Chang, Hui; Xiao, Weiwei; Zhang, Huizhong; Xi, Shaoyan; Liu, Mengzhong; Zhu, Yujia; Gao, Yuanhong

    2016-01-01

    We investigated the distribution of residual cancer cells (RCCs) within different layers of the bowel wall in surgical specimens and the value of biopsies of primary rectal lesion after preoperative volumetric modulated arc therapy (VMAT) with concurrent chemotherapy in patients with rectal cancer. Between April 2011 and April 2013, 178 patients with rectal cancer who received preoperative VMAT, concurrent chemotherapy, and surgery were evaluated; 79 of the patients received a biopsy of the primary lesion after chemoradiotherapy and prior to surgery. The distribution of RCCs in the surgical specimens and the sensitivity and specificity of the biopsy of primary rectal lesions for pathological response were evaluated. Fifty-two patients had a complete pathological response in the bowel wall. Of the 120 patients with ypT2-4, the rate of detection of RCCs in the mucosa, submucosa, and muscularis propria was 20%, 36.7%, 69.2%, respectively. The sensitivity and specificity of biopsies of primary rectal lesions was 12.9% and 94.1%, respectively. After chemoradiotherapy, the RCCs were primarily located in the deeper layers of the bowel wall, and the biopsy results for primary rectal lesions were unreliable due to poor sensitivity. PMID:27721486

  8. Pathological study of breast cancer by method postneaadyuvancia RCB (residual tumor burden) associated with cell proliferation index report preliminary data

    International Nuclear Information System (INIS)

    Full text: Introduction: The evaluation of residual disease increases prognostic information postneaadyuvancia and obtained by the study of pathological response. Using method index residual tumor burden (RCB)developed at M D Anderson where from morphological parameters (Size of the tumor bed, residual percentage of invasive carcinoma, carcinoma in situ percentage residual metastatic nodes number and size of largest metastasis)the index is calculated. Proliferation index represents an independent predictor of response to particular drugs. A high rate of cell proliferation after chemotherapy is linked with a poor survival We compared the results of both indices Material and Methods: We applied method residual tumor burden index (RCB)in 30 patients operated breast carcinoma after neoadjuvant therapy. Documentation was performed digital macroscopic bed residual tumor, printing and bulk sampling mapping performed on serially reading sheets histological double-blind by two pathologists using graphical illustrations of the percentage of cellularity neoplastic. The application of the formula classified as: RCB 0, complete pathological response (Rpc), RCB I, minimal residual disease, moderate residual disease RCB II, III RBC extensive disease residual. We immunohistochemical proliferation index (PI)with K i 67 in 14 cases (RCB II and III) with double-blinded histological evaluation by performing a percentage of stained nuclei in the greater staining sector thereof and with a cutoff of 14% of stained nuclei. Results: The size of the residual tumor bed was between 4x3mm and 110x60mm. Percentages cellularity invasive component between 0 and 86%, carcinoma in situ between 0 and 30 %. RCB case 0, RCB I a case, RCB RCB II and III seventeen cases eleven cases. Proliferation index was between 1% to 90 %, greater than 14 % in 29% of III and 21% RCB RCB II. Less than 14% was seen in 29% of RCB II and 7% RCB III In six cases there was variation in the rate of pre and post neoadjuvant

  9. Dendritic cell biology in human cytomegalovirus infection and the clinical consequences for host immunity and pathology

    OpenAIRE

    Gredmark-Russ, Sara; Söderberg-Nauclér, Cecilia

    2012-01-01

    Human cytomegalovirus (HCMV), a member of the herpesvirus family, establishes life-long persistence and latency after primary infection and can be reactivated later in life. In immunosuppressed patients, it is an important pathogen that can cause severe disease. HCMV is also thought to play a causative role in inflammatory diseases and cancer. The virus can infect different immune cells, including dendritic cells (DCs) and can take advantage of host immune functions to avoid immune recognitio...

  10. ROADS LESS TRAVELLED: SEXUAL DIMORPHISM AND MAST CELL CONTRIBUTIONS TO MIGRAINE PATHOLOGY

    Directory of Open Access Journals (Sweden)

    Andrea Ivonne Loewendorf

    2016-04-01

    Full Text Available Migraine is a common, little understood, and debilitating disease. It is much more prominent in women than in men (~2/3 are women but the reasons for female preponderance are not clear. Migraineurs frequently experience severe comorbidities such as allergies, depression, irritable bowel syndrome and others; many of the comorbities are more common in females. Current treatments for migraine are not gender-specific, and rarely are migraine and its comorbidities considered and treated by the same specialist. Thus, migraine treatments represent a huge unmet medical need, which will only be addressed with greater understanding of its underlying pathophysiology. We discuss the current knowledge about sex differences in migraine and its comorbidities, and focus in on the potential role of mast cells in both. Sex-based differences in pain recognition and drug responses, fluid balance, and the blood brain barrier are recognized but their impact on migraine is not well studied. Further, mast cells are well recognized for their prominent role in allergies but much less is known about their contributions to pain pathways in general and migraine specifically. Mast cell-neuron bidirectional communication uniquely positions these cells as potential initiators and/or perpetuators of pain. Mast cells can secrete nociceptor sensitizing and activating agents such as serotonin, prostaglandins, histamine and proteolytic enzymes that can also activate the pain-mediating transient receptor potential vanilloid (TRPV channels. Mast cells express receptors for both estrogen and progesterone that induce degranulation upon binding. Further, environmental estrogens such as Bisphenol A activate mast cells in preclinical models but their impact on pain pathways or migraine is understudied. We hope that this discussion will encourage scientists and physicians alike to bridge the knowledge gaps linking sex, mast cells and migraine to develop better, more comprehensive

  11. A microfluidic platform for systems pathology: multiparameter single-cell signaling measurements of clinical brain tumor specimens.

    Science.gov (United States)

    Sun, Jing; Masterman-Smith, Michael D; Graham, Nicholas A; Jiao, Jing; Mottahedeh, Jack; Laks, Dan R; Ohashi, Minori; DeJesus, Jason; Kamei, Ken-ichiro; Lee, Ki-Bum; Wang, Hao; Yu, Zeta T F; Lu, Yi-Tsung; Hou, Shuang; Li, Keyu; Liu, Max; Zhang, Nangang; Wang, Shutao; Angenieux, Brigitte; Panosyan, Eduard; Samuels, Eric R; Park, Jun; Williams, Dirk; Konkankit, Vera; Nathanson, David; van Dam, R Michael; Phelps, Michael E; Wu, Hong; Liau, Linda M; Mischel, Paul S; Lazareff, Jorge A; Kornblum, Harley I; Yong, William H; Graeber, Thomas G; Tseng, Hsian-Rong

    2010-08-01

    The clinical practice of oncology is being transformed by molecular diagnostics that will enable predictive and personalized medicine. Current technologies for quantitation of the cancer proteome are either qualitative (e.g., immunohistochemistry) or require large sample sizes (e.g., flow cytometry). Here, we report a microfluidic platform-microfluidic image cytometry (MIC)-capable of quantitative, single-cell proteomic analysis of multiple signaling molecules using only 1,000 to 2,800 cells. Using cultured cell lines, we show simultaneous measurement of four critical signaling proteins (EGFR, PTEN, phospho-Akt, and phospho-S6) within the oncogenic phosphoinositide 3-kinase (PI3K)/Akt/mammalian target of rapamycin (mTOR) signaling pathway. To show the clinical application of the MIC platform to solid tumors, we analyzed a panel of 19 human brain tumor biopsies, including glioblastomas. Our MIC measurements were validated by clinical immunohistochemistry and confirmed the striking intertumoral and intratumoral heterogeneity characteristic of glioblastoma. To interpret the multiparameter, single-cell MIC measurements, we adapted bioinformatic methods including self-organizing maps that stratify patients into clusters that predict tumor progression and patient survival. Together with bioinformatic analysis, the MIC platform represents a robust, enabling in vitro molecular diagnostic technology for systems pathology analysis and personalized medicine. PMID:20631065

  12. Nanoparticle-Based and Bioengineered Probes and Sensors to Detect Physiological and Pathological Biomarkers in Neural Cells.

    Science.gov (United States)

    Maysinger, Dusica; Ji, Jeff; Hutter, Eliza; Cooper, Elis

    2015-01-01

    Nanotechnology, a rapidly evolving field, provides simple and practical tools to investigate the nervous system in health and disease. Among these tools are nanoparticle-based probes and sensors that detect biochemical and physiological properties of neurons and glia, and generate signals proportionate to physical, chemical, and/or electrical changes in these cells. In this context, quantum dots (QDs), carbon-based structures (C-dots, grapheme, and nanodiamonds) and gold nanoparticles are the most commonly used nanostructures. They can detect and measure enzymatic activities of proteases (metalloproteinases, caspases), ions, metabolites, and other biomolecules under physiological or pathological conditions in neural cells. Here, we provide some examples of nanoparticle-based and genetically engineered probes and sensors that are used to reveal changes in protease activities and calcium ion concentrations. Although significant progress in developing these tools has been made for probing neural cells, several challenges remain. We review many common hurdles in sensor development, while highlighting certain advances. In the end, we propose some future directions and ideas for developing practical tools for neural cell investigations, based on the maxim "Measure what is measurable, and make measurable what is not so" (Galileo Galilei). PMID:26733793

  13. Nanoparticle-Based and Bioengineered Probes and Sensors to Detect Physiological and Pathological Biomarkers in Neural Cells.

    Science.gov (United States)

    Maysinger, Dusica; Ji, Jeff; Hutter, Eliza; Cooper, Elis

    2015-01-01

    Nanotechnology, a rapidly evolving field, provides simple and practical tools to investigate the nervous system in health and disease. Among these tools are nanoparticle-based probes and sensors that detect biochemical and physiological properties of neurons and glia, and generate signals proportionate to physical, chemical, and/or electrical changes in these cells. In this context, quantum dots (QDs), carbon-based structures (C-dots, grapheme, and nanodiamonds) and gold nanoparticles are the most commonly used nanostructures. They can detect and measure enzymatic activities of proteases (metalloproteinases, caspases), ions, metabolites, and other biomolecules under physiological or pathological conditions in neural cells. Here, we provide some examples of nanoparticle-based and genetically engineered probes and sensors that are used to reveal changes in protease activities and calcium ion concentrations. Although significant progress in developing these tools has been made for probing neural cells, several challenges remain. We review many common hurdles in sensor development, while highlighting certain advances. In the end, we propose some future directions and ideas for developing practical tools for neural cell investigations, based on the maxim "Measure what is measurable, and make measurable what is not so" (Galileo Galilei).

  14. Nanoparticle-based and bioengineered probes and sensors to detect physiological and pathological biomarkers in neural cells

    Directory of Open Access Journals (Sweden)

    Dusica eMaysinger

    2015-12-01

    Full Text Available Nanotechnology, a rapidly evolving field, provides simple and practical tools to investigate the nervous system in health and disease. Among these tools are nanoparticle-based probes and sensors that detect biochemical and physiological properties of neurons and glia, and generate signals proportionate to physical, chemical, and/or electrical changes in these cells. In this context, quantum dots (QDs, carbon-based structures (C-dots, graphene and nanodiamonds and gold nanoparticles are the most commonly used nanostructures. They can detect and measure enzymatic activities of proteases (metalloproteinases, caspases, ions, metabolites, and other biomolecules under physiological or pathological conditions in neural cells. Here, we provide some examples of nanoparticle-based and genetically engineered probes and sensors that are used to reveal changes in protease activities and calcium ion concentrations. Although significant progress in developing these tools has been made for probing neural cells, several challenges remain. We review many common hurdles in sensor development, while highlighting certain advances. In the end, we propose some future directions and ideas for developing practical tools for neural cell investigations, based on the maxim Measure what is measurable, and make measurable what is not so (Galileo Galilei.

  15. Attenuation of natural killer cell functions by capsaicin through a direct and TRPV1-independent mechanism.

    Science.gov (United States)

    Kim, Hun Sik; Kwon, Hyung-Joon; Kim, Gye Eun; Cho, Mi-Hyang; Yoon, Seung-Yong; Davies, Alexander J; Oh, Seog Bae; Lee, Heuiran; Cho, Young Keol; Joo, Chul Hyun; Kwon, Seog Woon; Kim, Sun Chang; Kim, Yoo Kyum

    2014-07-01

    The assessment of the biological activity of capsaicin, the compound responsible for the spicy flavor of chili pepper, produced controversial results, showing either carcinogenicity or cancer prevention. The innate immune system plays a pivotal role in cancer pathology and prevention; yet, the effect of capsaicin on natural killer (NK) cells, which function in cancer surveillance, is unclear. This study found that capsaicin inhibited NK cell-mediated cytotoxicity and cytokine production (interferon-γ and tumor necrosis factor-α). Capsaicin impaired the cytotoxicity of NK cells, thereby inhibiting lysis of standard target cells and gastric cancer cells by modulating calcium mobilization in NK cells. Capsaicin also induced apoptosis in gastric cancer cells, but that effect required higher concentrations and longer exposure times than those required to trigger NK cell dysfunction. Furthermore, capsaicin inhibited the cytotoxicity of isolated NK cells and of an NK cell line, suggesting a direct effect on NK cells. Antagonists of transient receptor potential vanilloid subfamily member 1 (TRPV1), a cognate capsaicin receptor, or deficiency in TRPV1 expression failed to prevent the defects induced by capsaicin in NK cells expressing functional TRPV1. Thus, the mechanism of action of capsaicin on NK cells is largely independent of TRPV1. Taken together, capsaicin may have chemotherapeutic potential but may impair NK cell function, which plays a central role in tumor surveillance. PMID:24743513

  16. Intracellular lipid in papillary renal cell carcinoma (pRCC): T2 weighted (T2W) MRI and pathologic correlation

    Energy Technology Data Exchange (ETDEWEB)

    Schieda, Nicola; Van der Pol, Christian B.; Moosavi, Bardia; McInnes, Matthew D.F. [The Ottawa Hospital, The University of Ottawa, Department of Medical Imaging, Ottawa, Ontario (Canada); Mai, Kien T.; Flood, Trevor A. [The Ottawa Hospital, The University of Ottawa, Department of Anatomical Pathology, Ottawa, Ontario (Canada)

    2015-07-15

    To evaluate if pRCCs demonstrate intracellular lipid (i-lipid) at chemical-shift (CS) MRI, and assess T2W-MRI and pathologic characteristics. Sixty-two patients with a pRCC diagnosis underwent MRI over 11 years (IRB-approved). Two radiologists independently assessed for presence of i-lipid on CS-MRI and homogeneity on T2W-MRI. Inter-observer agreement was assessed via an intraclass correlation and results were compared using the Chi-square test. Discordant cases were reviewed to establish consensus. T2W SI-ratios (SI.tumor/SI.kidney) and CS-SI index were compared using independent t-tests and Spearman correlation. Two pathologists re-evaluated the histopathology. Nine of the 62 pRCCs (14.5 %) demonstrated i-lipid; agreement was moderate (ICC = 0.63). Pathology review depicted clear cells in four tumours and foamy histiocytes in five tumours. 25.8-35.4 % (ICC = 0.65) of tumours were homogeneous on T2W-MRI. No pRCC with i-lipid was considered homogeneous (p = 0.01-0.04). Overall, T2W SI-ratio and CS-SI index were 0.89 (±0.29) and -3.63 % (-7.27 to 11.42). pRCC with i-lipid had significantly higher T2W SI-ratio (p = 0.003). There was a correlation between the CS-SI index and T2W SI-ratio, (r = 0.44, p < 0.001). Intracellular lipid is uncommonly detected in pRCCs due to clear cell changes and foamy histiocytes. These tumours are associated with heterogeneously-increased SI in T2W-MRI. (orig.)

  17. Of Amoebae and Men: Extracellular DNA Traps as an Ancient Cell-Intrinsic Defense Mechanism

    Science.gov (United States)

    Zhang, Xuezhi; Soldati, Thierry

    2016-01-01

    Since the discovery of the formation of DNA-based extracellular traps (ETs) by neutrophils as an innate immune defense mechanism (1), hundreds of articles describe the involvement of ETs in physiological and pathological human and animal conditions [reviewed in Ref. (2), and the previous Frontiers Research Topic on NETosis: http://www.frontiersin.org/books/NETosis_At_the_Intersection_of_Cell_Biology_Microbiology_and_Immunology/195]. Interestingly, a few reports reveal that ETs can be formed by immune cells of more ancient organisms, as far back as the common ancestor of vertebrates and invertebrates (3). Recently, we reported that the Sentinel cells of the multicellular slug of the social amoeba Dictyostelium discoideum also produce ETs to trap and kill slug-invading bacteria [see Box 1; and Figure 1 Ref. (4)]. This is a strong evidence that DNA-based cell-intrinsic defense mechanisms emerged much earlier than thought, about 1.3 billion years ago. Amazingly, using extrusion of DNA as a weapon to capture and kill uningestable microbes has its rationale. During the emergence of multicellularity, a primitive innate immune system developed in the form of a dedicated set of specialized phagocytic cells. This professionalization of immunity allowed the evolution of sophisticated defense mechanisms including the sacrifice of a small set of cells by a mechanism related to NETosis. This altruistic behavior likely emerged in steps, starting from the release of “dispensable” mitochondrial DNA by D. discoideum Sentinel cells. Grounded in this realization, one can anticipate that in the near future, many more examples of the invention and fine-tuning of ETs by early metazoan ancestors will be identified. Consequently, it can be expected that this more complete picture of the evolution of ETs will impact our views of the involvement and pathologies linked to ETs in human and animals. PMID:27458458

  18. Matter, metaphors, and mechanisms: rethinking cell theories.

    Science.gov (United States)

    Müller-Strahl, Gerhard

    2014-12-01

    This study analyzes the logical structure of classical cell theory (CCT) by pointing out that CCT conceives the properties of organic cellular matter as supervenient to successively emerging states of quasi-crystalline atoms. This concept supports the design of a metaphorical space the intelligible components of which display an explanatory structure in accordance with the contemporary complex-systems approach of mechanisms. These findings support the thesis of an explanatory turn within the life-sciences due to a conflict between anti-classificatory (Buffon), analogous (Wolff, Reil, Weber), and causal-mechanical (Kepler) strategies of explanation. The continuous process underlying these diverse discontinuities is taken to be the immanent process of objectifying scientific concepts for the need of explanation. This process repeatedly provides concepts which are identified as nomadic concepts. The meta-analysis of their interactions reveals that concepts of matter are obtained by idealizations which entertain one process with three dimensions: atomization originating from empirical classificatory regularities (classification) and aiming at an explanation of changing phenomena (dynamization). These dimensions are successfully incorporated into the explanatory scheme of CCT. The migrations of a second group of nomadic concepts beyond this historical point of transition are made responsible for blurring the explanatory turn.

  19. THz spectroscopy of whole blood, plasma and cells in mice of SHR line with various pathology

    Science.gov (United States)

    Panchenko, A.; Tyndyk, M.; Smolyanskaya, O.; Sulatskiy, M.; Kravtsenyuk, O.; Balbekin, N.; Khodzitsky, M.

    2016-08-01

    This paper is devoted to studying of optical properties of whole blood and blood plasma in SHR mice grafted Ehrlich's carcinoma and mice with chronic inflammation at the terahertz frequency range. Additionally physiological saline solution suspension of ascites Ehrlich's carcinoma cells was explored.

  20. Micro and Nano-scale Technologies for Cell Mechanics

    OpenAIRE

    Mustafa Unal; Yunus Alapan; Hao Jia; Adrienn G. Varga; Keith Angelino; Mahmut Aslan; Ismail Sayin; Chanjuan Han; Yanxia Jiang; Zhehao Zhang; Gurkan, Umut A.

    2014-01-01

    Cell mechanics is a multidisciplinary field that bridges cell biology, fundamental mechanics, and micro and nanotechnology, which synergize to help us better understand the intricacies and the complex nature of cells in their native environment. With recent advances in nanotechnology, microfabrication methods and micro-electro-mechanical-systems (MEMS), we are now well situated to tap into the complex micro world of cells. The field that brings biology and MEMS togethe...

  1. Single cell mechanics: stress stiffening and kinematic hardening

    CERN Document Server

    Fernández, Pablo

    2007-01-01

    Cell mechanical properties are fundamental to the organism but remain poorly understood. We report a comprehensive phenomenological framework for the nonlinear rheology of single fibroblast cells: a superposition of elastic stiffening and viscoplastic kinematic hardening. Our results show, that in spite of cell complexity its mechanical properties can be cast into simple, well-defined rules, which provide mechanical cell strength and robustness via control of crosslink slippage.

  2. Single cell mechanics: stress stiffening and kinematic hardening.

    Science.gov (United States)

    Fernández, Pablo; Ott, Albrecht

    2008-06-13

    Cell mechanical properties are fundamental to the organism but remain poorly understood. We report a comprehensive phenomenological framework for the complex rheology of single fibroblast cells: a superposition of elastic stiffening and viscoplastic kinematic hardening. Despite the complexity of the living cell, its mechanical properties can be cast into simple, well-defined rules. Our results reveal the key role of crosslink slippage in determining mechanical cell strength and robustness. PMID:18643547

  3. Application of Molecular Pathology in Endocrine Pathology.

    Science.gov (United States)

    Linke, Ebru Serinsoz; Tezel, Gaye Güler

    2015-01-01

    Rapid growth in knowledge of cell and molecular biology led to the increased usage of molecular techniques in anatomical pathology. This is also due to the advances achieved in the techniques introduced in the last few years which are less laborious as compared to the techniques used at the beginning of the "molecular era". The initial assays were also very expensive and were not performed except for selected centers. Moreover, the clinicians were not sure how to make use of the accumulating molecular information. That situation has also changed and molecular techniques are being performed in a wide variety of medical settings which also has a reflection on the endocrine system pathology among other organ systems. This review will provide an update of genetic changes observed in different endocrine system pathologies and their diagnostic, therapeutic and prognostic values.

  4. Common mechanisms linking connexin43 to neural progenitor cell migration and glioma invasion.

    Science.gov (United States)

    Naus, Christian C; Aftab, Qurratulain; Sin, Wun Chey

    2016-02-01

    Cell migration is critical for cell differentiation, tissue formation and organ development. Several mechanisms come to play in the process of cell migration, orchestrating changes in cell polarity, adhesion, process extension and motility. Recent findings have shown that gap junctions, and specifically connexin43 (Cx43), can play a significant role in these processes, impacting adhesion and cytoskeletal rearrangements. Thus Cx43 within a cell regulates its motility and migration via intracellular signaling. Furthermore, Cx43 in the host cells can impact the degree of cellular migration through that tissue. Similarities in these connexin-based processes account for both neural progenitor migration in the developing brain, and for glioma cell invasion in the mature brain. In both cases, Cx43 in the tissue ("soil") in which cells ("seeds") exist facilitates their migration and, for glioma cells, tissue invasion. Cx43 mediates these effects through channel- and non-channel-dependent mechanisms which have similarities in both paradigms of cell migration. This provides insight into developmental processes and pathological situations, as well as possible therapeutic approaches regarding specific functional domains of gap junction proteins.

  5. Clinical-Pathological Parameters as Prognostic Indicators in Oral Squamous Cell

    Directory of Open Access Journals (Sweden)

    Raimundo Fernandes de ARAÚJO JÚNIOR

    2006-08-01

    Full Text Available Objective: To correlate the TNM classification and histological scores of malignancy, and these parameters with the prognosis in 38 cases of squamous cell carcinoma oral. Method: The cases were selected from the files of "Dr. Luiz Antônio" Cancer Hospital, Natal, RN, Brazil. After analysis of the patients' records, the data concerning TNM classification and prognosis (in a 5-year-follow-up were obtained. All cases were classified according to the histological malignancy grading system proposed by Bryne (1998. Results: There was correlation between histological scores of malignancy and prognosis and TNM classification with prognosis. Conclusion: It was concluded that TNM classification and histological malignancy grading are important prognostic indicators the squamous cell carcinoma oral.

  6. Sox17 regulates insulin secretion in the normal and pathologic mouse β cell.

    Directory of Open Access Journals (Sweden)

    Diva Jonatan

    Full Text Available SOX17 is a key transcriptional regulator that can act by regulating other transcription factors including HNF1β and FOXA2, which are known to regulate postnatal β cell function. Given this, we investigated the role of SOX17 in the developing and postnatal pancreas and found a novel role for SOX17 in regulating insulin secretion. Deletion of the Sox17 gene in the pancreas (Sox17-paLOF had no observable impact on pancreas development. However, Sox17-paLOF mice had higher islet proinsulin protein content, abnormal trafficking of proinsulin, and dilated secretory organelles suggesting that Sox17-paLOF adult mice are prediabetic. Consistant with this, Sox17-paLOF mice were more susceptible to aged-related and high fat diet-induced hyperglycemia and diabetes. Overexpression of Sox17 in mature β cells using Ins2-rtTA driver mice resulted in precocious secretion of proinsulin. Transcriptionally, SOX17 appears to broadly regulate secretory networks since a 24-hour pulse of SOX17 expression resulted in global transcriptional changes in factors that regulate hormone transport and secretion. Lastly, transient SOX17 overexpression was able to reverse the insulin secretory defects observed in MODY4 animals and restored euglycemia. Together, these data demonstrate a critical new role for SOX17 in regulating insulin trafficking and secretion and that modulation of Sox17-regulated pathways might be used therapeutically to improve cell function in the context of diabetes.

  7. Clinical and Pathological Complete Remission in a Patient With Metastatic Renal Cell Carcinoma (mRCC Treated With Sunitinib: Is mRCC Curable With Targeted Therapy?

    Directory of Open Access Journals (Sweden)

    Amishi Y. Shah

    2015-03-01

    Full Text Available We report a patient with metastatic clear-cell renal cell carcinoma (mRCC who presented with primary tumor in situ in the left kidney and metastases to bone, liver, lungs, and brain. After over 5 years of sunitinib therapy and subsequent cytoreductive left nephrectomy, the patient achieved radiographic complete response (CR and had pathologic CR in the nephrectomy specimen. Durable clinical and pathological CRs are possible with targeted agents, even with primary tumor in situ and widely disseminated metastases. Ongoing research will define the optimal duration of systemic therapy in exceptional responders and identify the molecular determinants of response and resistance.

  8. Cell mechanics and mechanotransduction: pathways, probes, and physiology.

    Science.gov (United States)

    Huang, Hayden; Kamm, Roger D; Lee, Richard T

    2004-07-01

    Cells face not only a complex biochemical environment but also a diverse biomechanical environment. How cells respond to variations in mechanical forces is critical in homeostasis and many diseases. The mechanisms by which mechanical forces lead to eventual biochemical and molecular responses remain undefined, and unraveling this mystery will undoubtedly provide new insight into strengthening bone, growing cartilage, improving cardiac contractility, and constructing tissues for artificial organs. In this article we review the physical bases underlying the mechanotransduction process, techniques used to apply controlled mechanical stresses on living cells and tissues to probe mechanotransduction, and some of the important lessons that we are learning from mechanical stimulation of cells with precisely controlled forces.

  9. Aggregates of mutant CFTR fragments in airway epithelial cells of CF lungs: new pathologic observations.

    Science.gov (United States)

    Du, Kai; Karp, Philip H; Ackerley, Cameron; Zabner, Joseph; Keshavjee, Shaf; Cutz, Ernest; Yeger, Herman

    2015-03-01

    Cystic fibrosis (CF) is caused by a mutation in the CF transmembrane conductance regulator (CFTR) gene resulting in a loss of Cl(-) channel function, disrupting ion and fluid homeostasis, leading to severe lung disease with airway obstruction due to mucus plugging and inflammation. The most common CFTR mutation, F508del, occurs in 90% of patients causing the mutant CFTR protein to misfold and trigger an endoplasmic reticulum based recycling response. Despite extensive research into the pathobiology of CF lung disease, little attention has been paid to the cellular changes accounting for the pathogenesis of CF lung disease. Here we report a novel finding of intracellular retention and accumulation of a cleaved fragment of F508del CFTR in concert with autophagic like phagolysosomes in the airway epithelium of patients with F508del CFTR. Aggregates consisting of poly-ubiquitinylated fragments of only the N-terminal domain of F508del CFTR but not the full-length molecule accumulate to appreciable levels. Importantly, these undegraded intracytoplasmic aggregates representing the NT-NBD1 domain of F508del CFTR were found in ciliated, in basal, and in pulmonary neuroendocrine cells. Aggregates were found in both native lung tissues and ex-vivo primary cultures of bronchial epithelial cells from CF donors, but not in normal control lungs. Our findings present a new, heretofore, unrecognized innate CF gene related cell defect and a potential contributing factor to the pathogenesis of CF lung disease. Mutant CFTR intracytoplasmic aggregates could be analogous to the accumulation of misfolded proteins in other degenerative disorders and in pulmonary "conformational protein-associated" diseases. Consequently, potential alterations to the functional integrity of airway epithelium and regenerative capacity may represent a critical new element in the pathogenesis of CF lung disease.

  10. Whirler Mutant Hair Cells Have Less Severe Pathology than Shaker 2 or Double Mutants

    OpenAIRE

    Mustapha, Mirna; Lisa A. Beyer; Izumikawa, Masahiko; Swiderski, Donald L.; Dolan, David F.; Raphael, Yehoash; Camper, Sally A.

    2007-01-01

    MYOSIN XV is a motor protein that interacts with the PDZ domain-containing protein WHIRLIN and transports WHIRLIN to the tips of the stereocilia. Shaker 2 (sh2) mice have a mutation in the motor domain of MYOSIN XV and exhibit congenital deafness and circling behavior, probably because of abnormally short stereocilia. Whirler (wi) mice have a similar phenotype caused by a deletion in the third PDZ domain of WHIRLIN. We compared the morphology of Whrnwi/wi and Myo15sh2/sh2 sensory hair cells a...

  11. Time to Relax: Mechanical Stress Release Guides Stem Cell Responses.

    Science.gov (United States)

    Sommerfeld, Sven D; Elisseeff, Jennifer H

    2016-02-01

    Stem cells integrate spatiotemporal cues, including the mechanical properties of their microenvironment, into their fate decisions. Chaudhuri et al. (2015) show that the ability of the extracellular matrix to dissipate cell-induced forces, referred to as stress-relaxation, is a key mechanical signal influencing stem cell fate and function. PMID:26849301

  12. Neural Stem Cell Gene Therapy Ameliorates Pathology and Function in a Mouse Model of Globoid Cell Leukodystrophy

    OpenAIRE

    Neri, Margherita; Ricca, Alessandra; di Girolamo, Ilaria; Alcala'-Franco, Beatriz; Cavazzin, Chiara; Orlacchio, Aldo; Martino, Sabata; Naldini, Luigi; Gritti, Angela

    2011-01-01

    Murine neural stem cells (mNSCs), either naive or genetically modified to express supranormal levels of β-galactocerebrosidase (GALC), were transplanted into the brain of Twitcher mice, a murine model of globoid cell leukodystrophy, a severe sphingolipidosis. Cells engrafted long-term into the host cytoarchitecture, producing functional GALC. Levels of enzyme activity in brain and spinal cord tissues were enhanced when GALC-overexpressing NSC were used. Enzymatic correction correlated with re...

  13. Pro-angiogenic Hematopoietic Progenitor Cells and Endothelial Colony Forming Cells in Pathological Angiogenesis of Bronchial and Pulmonary Circulation

    OpenAIRE

    Duong, Heng; Erzurum, Serpil; Asosingh, Kewal

    2011-01-01

    Dysregulation of angiogenesis is a common feature of many disease processes. Vascular remodeling is believed to depend on the participation of endothelial progenitor cells, but the identification of endothelial progenitors in postnatal neovascularization remains elusive. Current understanding posits a role for circulating pro-angiogenic hematopoietic cells, which interact with local endothelial cells to establish an environment that favors angiogenesis in physiologic and pathophysiologic resp...

  14. Langerhans' cell histiocytosis: pathology, imaging and treatment of skeletal involvement

    Energy Technology Data Exchange (ETDEWEB)

    Azouz, E. Michel [University of Miami, Pediatric Radiology Section, Department of Radiology, Miami, FL (United States); Saigal, Gaurav [McGill University, Department of Medical Imaging, Quebec (Canada); Rodriguez, Maria M. [University of Miami, Department of Pathology, Miami, FL (United States); Podda, Antonello [University of Miami, Division of Pediatric Hematology/Oncology, Miami, FL (United States)

    2005-02-01

    Langerhans' cell histiocytosis (LCH) is manifested in a variety of ways, the most common being the eosinophilic granuloma, a localized, often solitary bone lesion that occurs predominantly in the pediatric age group. The hallmark of LCH is the proliferation and accumulation of a specific histiocyte: the Langerhans' cell. In bone this may cause pain and adjacent soft-tissue swelling, but some lesions are asymptomatic. LCH can involve any bone, but most lesions occur in the skull (especially the calvarium and temporal bones), the pelvis, spine, mandible, ribs, and tubular bones. Imaging diagnosis of the disease in bone is first based on the plain radiographic appearance, which is usually a central destructive, aggressive-looking lesion. In the skull, the lesions develop in the diploic space, are lytic, and their edges may be beveled, scalloped or confluent (geographic), or show a ''button sequestrum.'' Vertebral body involvement usually causes collapse, resulting in vertebra plana. With significant recent improvements in the quality of gamma cameras, imaging techniques, and in studying children, bone scintigraphy at diagnosis and on follow-up usually reveals the sites of active disease, especially when the involvement is polyostotic. CT and MR imaging are very useful in providing detailed cross-sectional anatomic detail of the involved bone, including the bone marrow and the adjacent soft tissues. CT is better suited for demonstrating bone detail and MR imaging for bone marrow and soft-tissue involvement. (orig.)

  15. The Role of RhoJ in Endothelial Cell Biology and Tumor Pathology

    Science.gov (United States)

    Shi, Ting-Ting; Li, Gang

    2016-01-01

    Background. RhoJ, an endothelially expressed member of Cdc42 (cell division cycle 42) subfamily of Rho GTPase, plays an important role in endocytic pathway, adipocyte differentiation, endothelial motility, tube formation, and focal adhesion. RhoJ is a selective and effective therapeutic target in tumor tissues or retinopathy. Methods. A systematic review was related to “small Rho GTPase” or “RhoJ” with “endothelial motility, tube formation and focal adhesion” and “tumor therapy”. This led to many cross-references involving RhoJ and these data have been incorporated into the following study. Results. We have grouped the role of RhoJ according to three main effects: RhoJ regulates endocytic pathway and adipocyte differentiation in early studies, and RhoJ shows an important role in endothelial cell biology; furthermore, RhoJ blockade serves as a target in tumor vasculature and enhances the effects of anticancer drug. Conclusions. More research is necessary to understand the role of RhoJ in many aspects, on the basis of current knowledge of the role of RhoJ blockade in tumor vessels, there are opportunities for the therapy of tumor, and RhoJ is expressed outside tumour vasculature and is involved in wound healing. Taking advantage of the opportunities could result in a development in tumor therapy. PMID:27556037

  16. Clinico-pathological impact of cytogenetic subgroups in B-cell chronic lymphocytic leukemia: Experience from India

    Directory of Open Access Journals (Sweden)

    PS Kadam Amare

    2013-01-01

    Full Text Available Background: The present study of 238 B-cell Chronic Lymphocytic Leukemia (B-CLL patients were undertaken to seek the prevalence and to evaluate clinico-pathological significance of recurrent genetic abnormalities such as del(13q14.3, trisomy 12, del(11q22.3 (ATM, TP53 deletion, del(6q21 and IgH translocation/deletion. Materials and Methods: We applied interphase - fluorescence in situ hybridization (FISH on total 238 cases of B-CLL. Results: Our study disclosed 69% of patients with genetic aberrations such as 13q deletion (63%, trisomy 12 (28%, 11q deletion (18%, 6q21 deletion (11% with comparatively higher frequency of TP53 deletion (22%. Deletion 13q displayed as a most frequent sole abnormality. In group with coexistence of ≥2 aberrations, 13q deletion was a major clone indicating del(13q as a primary event followed by 11q deletion, TP53 deletion, trisomy 12, 6q deletion as secondary progressive events. In comparison with del(13q, trisomy 12, group with coexistence of ≥2 aberrations associated with poor risk factors such as hyperleukocytosis, advanced stage, and multiple nodes involvement. In a separate study of 116 patients, analysis of IgH abnormalities revealed either partial deletion (24% or translocation (5% and were associated with del(13q, trisomy 12, TP53 and ATM deletion. Two of 7 cases had t(14;18, one case had t(8;14, and four cases had other variant IgH translocation t(?;14. Conclusion: Detail characterization and clinical impact are necessary to ensure that IgH translocation positive CLL is a distinct pathological entity. Our data suggests that CLL with various cytogenetic subsets, group with coexistence of ≥2 aberrations seems to be a complex cytogenetic subset, needs more attention to understand biological significance and to seek clinical impact for better management of disease.

  17. Oral squamous cell carcinoma: clinicopathological features from 346 cases from a single Oral Pathology service during an 8-year period

    Directory of Open Access Journals (Sweden)

    Fabio Ramoa Pires

    2013-09-01

    Full Text Available Epidemiological data from oral squamous cell carcinoma (OSCC is mostly derived from North American, European and East Asian populations. OBJECTIVE: The aim of this study was to report the demographic and clinicopathological features from OSCC diagnosed in an Oral Pathology service in southeastern Brazil in an 8-year period. MATERIAL AND METHODS: All OSCC diagnosed from 2005 to 2012 were reviewed, including histological analysis of all hematoxylin and eosin stained slides and review of all demographic and clinical information from the laboratory records. RESULTS: A total of 346 OSCC was retrieved and males represented 67% of the sample. Mean age of the patients was 62.3 years-old and females were affected a decade older than males (p<0.001. Mean time of complaint with the tumors was 10 months and site distribution showed that the border of the tongue (37%, alveolar mucosa/gingiva (20% and floor of mouth/ventral tongue (19% were the most common affected sites. Mean size of the tumors was 3.4 cm, with no differences for males and females (p=0.091 and males reported both tobacco and alcohol consumption more frequently than females. Histological grade of the tumors revealed that 27%, 40% and 21% of the tumors were, respectively, classified as well-, moderately- and poorly-differentiated OSCC, 26 cases (7.5% were microinvasive OSCC and 17 cases were OSCC variants. OSCC in males mostly affected the border of tongue, floor of mouth/ventral tongue and alveolar mucosa/gingival, while they were more frequent on the border of tongue, alveolar mucosa/gingival and buccal mucosa/buccal sulcus in females (p=0.004. CONCLUSIONS: The present data reflect the epidemiological characteristics of OSCC diagnosed in a public Oral Pathology laboratory in southeastern Brazil and have highlighted several differences in clinicopathological features when comparing male and female OSCC-affected patients.

  18. Diffuse large B-Cell lymphoma: a clinico- pathologic and prognostic study on 1470 biopsy specimens

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    Sadighi S

    2009-11-01

    Full Text Available "n Normal 0 false false false EN-US X-NONE AR-SA MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:Arial; mso-bidi-theme-font:minor-bidi;} Background: Diffuse large B Cell lymphoma (DLBCL is the most common subtype of non-Hogkin lymphoma (NHL. We performed a retrospective study of patients with de novo DLBCL treated in the Medical Oncology department of Cancer Institute of Iran, Tehran to assess the clinicopathologic and immunohistochemistry correlation and prognosis of the patients. "n"nMethods: World Health Organization (WHO classification was used to reexamine 1470 biopsy specimens related to the years 1985-2006. After excluding five cases of T Cell large cell lymphoma, 50 Patients diagnosed as DLBCL. "n"nResults: Median age of the patients was 45.5(20-85 years: 60% were male and 30% had primary extranodal disease. The most common extranodal sites were bone, gastrointestinal tract and Head and neck areas. The most common stages were stage II (32%, stage III (32%, stage IV (20% and stage I (16% retrospectively and 33% had B-symptoms. All of The Patients received chemotherapy (83% CHOP regimen and 46% treated by radiotherapy after chemotherapy. With a mean follow up time of 32 months, median survival time was 34 (95% CI 24-40 months. Prognostic factors for survival were tumor stage, B-symptoms and early relapse (less than 6 months."n"nConclusions: Our

  19. Risk factors of brain metastases in completely resected pathological stage IIIA-N2 non-small cell lung cancer

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    Ding Xiao

    2012-07-01

    Full Text Available Abstract Background Brain metastases (BM is one of the most common failures of locally advanced non-small cell lung cancer (LA-NSCLC after combined-modality therapy. The outcome of trials on prophylactic cranial irradiation (PCI has prompted us to identify the highest-risk subset most likely to benefit from PCI. Focusing on patients with completely resected pathological stage IIIA-N2 (pIIIA-N2 NSCLC, we aimed to assess risk factors of BM and to define the highest-risk subset. Methods Between 2003 and 2005, the records of 217 consecutive patients with pIIIA-N2 NSCLC in our institution were reviewed. The cumulative incidence of BM was estimated using the Kaplan–Meier method, and differences between the groups were analyzed using log-rank test. Multivariate Cox regression analysis was applied to assess risk factors of BM. Results Fifty-three (24.4 % patients developed BM at some point during their clinical course. On multivariate analysis, non-squamous cell cancer (relative risk [RR]: 4.13, 95 % CI: 1.86–9.19; P = 0.001 and the ratio of metastatic to examined nodes or lymph node ratio (LNR ≥ 30 % (RR: 3.33, 95 % CI: 1.79–6.18; P = 0.000 were found to be associated with an increased risk of BM. In patients with non-squamous cell cancer and LNR ≥ 30 %, the 5-year actuarial risk of BM was 57.3 %. Conclusions In NSCLC, patients with completely resected pIIIA-N2 non-squamous cell cancer and LNR ≥ 30 % are at the highest risk for BM, and are most likely to benefit from PCI. Further studies are warranted to investigate the effect of PCI on this subset of patients.

  20. Digital pathology

    CERN Document Server

    Sucaet, Yves

    2014-01-01

    Digital pathology has experienced exponential growth, in terms of its technology and applications, since its inception just over a decade ago. Though it has yet to be approved for primary diagnostics, its values as a teaching tool, facilitator of second opinions and quality assurance reviews and research are becoming, if not already, undeniable. It also offers the hope of providing pathology consultant and educational services to under-served areas, including regions of the world that could not possibly sustain this level of services otherwise. And this is just the beginning, as its adoption b

  1. Roads Less Traveled: Sexual Dimorphism and Mast Cell Contributions to Migraine Pathology.

    Science.gov (United States)

    Loewendorf, Andrea I; Matynia, Anna; Saribekyan, Hakob; Gross, Noah; Csete, Marie; Harrington, Mike

    2016-01-01

    Migraine is a common, little understood, and debilitating disease. It is much more prominent in women than in men (~2/3 are women) but the reasons for female preponderance are not clear. Migraineurs frequently experience severe comorbidities, such as allergies, depression, irritable bowel syndrome, and others; many of the comorbidities are more common in females. Current treatments for migraine are not gender specific, and rarely are migraine and its comorbidities considered and treated by the same specialist. Thus, migraine treatments represent a huge unmet medical need, which will only be addressed with greater understanding of its underlying pathophysiology. We discuss the current knowledge about sex differences in migraine and its comorbidities, and focus on the potential role of mast cells (MCs) in both. Sex-based differences in pain recognition and drug responses, fluid balance, and the blood-brain barrier are recognized but their impact on migraine is not well studied. Furthermore, MCs are well recognized for their prominent role in allergies but much less is known about their contributions to pain pathways in general and migraine specifically. MC-neuron bidirectional communication uniquely positions these cells as potential initiators and/or perpetuators of pain. MCs can secrete nociceptor sensitizing and activating agents, such as serotonin, prostaglandins, histamine, and proteolytic enzymes that can also activate the pain-mediating transient receptor potential vanilloid channels. MCs express receptors for both estrogen and progesterone that induce degranulation upon binding. Furthermore, environmental estrogens, such as Bisphenol A, activate MCs in preclinical models but their impact on pain pathways or migraine is understudied. We hope that this discussion will encourage scientists and physicians alike to bridge the knowledge gaps linking sex, MCs, and migraine to develop better, more comprehensive treatments for migraine patients. PMID:27148260

  2. Cell Junction Pathology of Neural Stem Cells Is Associated With Ventricular Zone Disruption, Hydrocephalus, and Abnormal Neurogenesis

    NARCIS (Netherlands)

    Montserrat Guerra, Maria; Henzi, Roberto; Ortloff, Alexander; Lichtin, Nicole; Vio, Karin; Jimenez, Antonio J.; Dolores Dominguez-Pinos, Maria; Gonzalez, Cesar; Clara Jara, Maria; Hinostroza, Fernando; Rodriguez, Sara; Jara, Maryoris; Ortega, Eduardo; Guerra, Francisco; Sival, Deborah A.; den Dunnen, Wilfred F. A.; Perez-Figares, Jose M.; McAllister, James P.; Johanson, Conrad E.; Rodriguez, Esteban M.

    2015-01-01

    Fetal-onset hydrocephalus affects 1 to 3 per 1,000 live births. It is not only a disorder of cerebrospinal fluid dynamics but also a brain disorder that corrective surgery does not ameliorate. We hypothesized that cell junction abnormalities of neural stem cells (NSCs) lead to the inseparable phenom

  3. Mechanical tension drives cell membrane fusion

    OpenAIRE

    Kim, Ji Hoon; Ren, Yixin; Ng, Win Pin; Li, Shuo; Son, Sungmin; Kee, Yee-Seir; Zhang, Shiliang; Zhang, Guofeng; Fletcher, Daniel A.; Robinson, Douglas N.; Chen, Elizabeth H.

    2015-01-01

    Membrane fusion is an energy-consuming process that requires tight juxtaposition of two lipid bilayers. Little is known about how cells overcome energy barriers to bring their membranes together for fusion. Previously, we have shown that cell-cell fusion is an asymmetric process in which an “attacking” cell drills finger-like protrusions into the “receiving” cell to promote cell fusion. Here we show that the receiving cell mounts a Myosin II (MyoII)-mediated mechanosensory response to its inv...

  4. Mechanism for collective cell alignment in Myxococcus xanthus bacteria

    CERN Document Server

    Balagam, Rajesh

    2015-01-01

    M. xanthus cells self-organize into clusters, aligned cell groups, at various stages of its lifecycle. Formation of these clusters is crucial for complex dynamic multi-cellular behavior of these bacteria. However the mechanism underlying the cell alignment and clustering is not fully understood. Motivated by studies of clustering in self-propelled rods, we hypothesized that M. xanthus cells can align and form clusters through pure mechanical interactions among cells and between cells and substrate. We test this hypothesis using an agent-based simulation framework where each agent is based on biophysical model of individual M. xanthus cell. We show that model agents, under realistic cell flexibility values, can align and form cell clusters but only when periodic reversals of cell directions are suppressed. However, by extending our model to introduce observed ability of cells to lay and follow slime trails, we show that effective trail following leads to clusters in reversing cells. Furthermore, we conclude th...

  5. Protective mechanism against cancer found in progeria patient cells

    Science.gov (United States)

    NCI scientists have studied cells of patients with an extremely rare genetic disease that is characterized by drastic premature aging and discovered a new protective cellular mechanism against cancer. They found that cells from patients with Hutchinson Gi

  6. New mechanism for neural stem cell maintenance in early embryos

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    @@ Teamning up with co-workers from Japan, UK and US,CAS biochemists have revealed a novel mechanism for maintaining neural stem cells in early embryos. Their work was published on the 6 August issue of Cell Development.

  7. Cell cycle control, checkpoint mechanisms, and genotoxic stress.

    OpenAIRE

    R.E. Shackelford; Kaufmann, W K; Paules, R S

    1999-01-01

    The ability of cells to maintain genomic integrity is vital for cell survival and proliferation. Lack of fidelity in DNA replication and maintenance can result in deleterious mutations leading to cell death or, in multicellular organisms, cancer. The purpose of this review is to discuss the known signal transduction pathways that regulate cell cycle progression and the mechanisms cells employ to insure DNA stability in the face of genotoxic stress. In particular, we focus on mammalian cell cy...

  8. Structures and molecular mechanisms for common 15q13.3 microduplications involving CHRNA7: benign or pathological?

    Science.gov (United States)

    Szafranski, Przemyslaw; Schaaf, Christian P; Person, Richard E; Gibson, Ian B; Xia, Zhilian; Mahadevan, Sangeetha; Wiszniewska, Joanna; Bacino, Carlos A; Lalani, Seema; Potocki, Lorraine; Kang, Sung-Hae; Patel, Ankita; Cheung, Sau Wai; Probst, Frank J; Graham, Brett H; Shinawi, Marwan; Beaudet, Arthur L; Stankiewicz, Pawel

    2010-07-01

    We have investigated four approximately 1.6-Mb microduplications and 55 smaller 350-680-kb microduplications at 15q13.2-q13.3 involving the CHRNA7 gene that were detected by clinical microarray analysis. Applying high-resolution array-CGH, we mapped all 118 chromosomal breakpoints of these microduplications. We also sequenced 26 small microduplication breakpoints that were clustering at hotspots of nonallelic homologous recombination (NAHR). All four large microduplications likely arose by NAHR between BP4 and BP5 LCRs, and 54 small microduplications arose by NAHR between two CHRNA7-LCR copies. We identified two classes of approximately 1.6-Mb microduplications and five classes of small microduplications differing in duplication size, and show that they duplicate the entire CHRNA7. We propose that size differences among small microduplications result from preexisting heterogeneity of the common BP4-BP5 inversion. Clinical data and family histories of 11 patients with small microduplications involving CHRNA7 suggest that these microduplications might be associated with developmental delay/mental retardation, muscular hypotonia, and a variety of neuropsychiatric disorders. However, we conclude that these microduplications and their associated potential for increased dosage of the CHRNA7-encoded alpha 7 subunit of nicotinic acetylcholine receptors are of uncertain clinical significance at present. Nevertheless, if they prove to have a pathological effects, their high frequency could make them a common risk factor for many neurobehavioral disorders.

  9. Generating and characterizing the mechanical properties of cell-derived matrices using atomic force microscopy.

    Science.gov (United States)

    Tello, Marta; Spenlé, Caroline; Hemmerlé, Joseph; Mercier, Luc; Fabre, Roxane; Allio, Guillaume; Simon-Assmann, Patricia; Goetz, Jacky G

    2016-02-01

    Mechanical interaction between cells and their surrounding extracellular matrix (ECM) controls key processes such as proliferation, differentiation and motility. For many years, two-dimensional (2D) models were used to better understand the interactions between cells and their surrounding ECM. More recently, variation of the mechanical properties of tissues has been reported to play a major role in physiological and pathological scenarios such as cancer progression. The 3D architecture of the ECM finely tunes cellular behavior to perform physiologically relevant tasks. Technical limitations prevented scientists from obtaining accurate assessment of the mechanical properties of physiologically realistic matrices. There is therefore a need for combining the production of high-quality cell-derived 3D matrices (CDMs) and the characterization of their topographical and mechanical properties. Here, we describe methods that allow to accurately measure the young modulus of matrices produced by various cellular types. In the first part, we will describe and review several protocols for generating CDMs matrices from endothelial, epithelial, fibroblastic, muscle and mesenchymal stem cells. We will discuss tools allowing the characterization of the topographical details as well as of the protein content of such CDMs. In a second part, we will report the methodologies that can be used, based on atomic force microscopy, to accurately evaluate the stiffness properties of the CDMs through the quantification of their young modulus. Altogether, such methodologies allow characterizing the stiffness and topography of matrices deposited by the cells, which is key for the understanding of cellular behavior in physiological conditions.

  10. Nanoscale Mechanical Stimulation of Human Mesenchymal Stem Cells

    Directory of Open Access Journals (Sweden)

    H Nikukar

    2014-05-01

    We observed significant responses after 1 and 2-week stimulations in cell number, cell shapes and phenotypical markers. Microarray was performed for all groups. Cell count showed normal cell growth with stimulation. However, cell surface area, cell perimeter, and arboration after 1-week stimulation showed significant increases. Immunofluorescent studies have showed significant increase in osteocalcin production after stimulation. Conclusions: Nanoscale mechanical vibration showed significant changes in human mesenchymal stem cell behaviours. Cell morphology changed to become more polygonal and increased expression of the osteoblast markers were noted. These findings with gene regulation changes suggesting nanoscale mechanostimulation has stimulated osteoblastogenesis.  Keywords:  Mesenchymal, Nanoscale, Stem Cells.

  11. Analysis of Pathological Diagnosis of Renal Clear Cell Carcinoma%肾脏透明细胞癌的病理诊断分析

    Institute of Scientific and Technical Information of China (English)

    杜晓敏

    2015-01-01

    Objective To investigate the pathological diagnosis of renal clear cell carcinoma. Methods The 163 patients were re-garded as research subjects, which pathological diagnosis of renal clear cell carcinoma in Pathology from 2011 January to 2014 June, and the pathological data were retrospectively analyzed. Results In 163 patients, renal clear cell carcinoma grade I 56 cases, accounting for 34.4%, renal cell carcinoma 43 cases, accounting for 26.4%, clear cell renal III 35 cases, accounting for 21.5%, re-nal clear cell carcinoma grade IV 29 cases, accounting for 17.7%. Under microscope, tumor cells larger, circular or polygonal, abundant cytoplasm, transparent, full of interstitial capillaries and sinuses. Conclusion The pathological diagnosis was observed under microscope in tissue structure and cell lesion characteristics and disease diagnosis made, Renal clear cell carcinoma is the most common malignant tumor, renal cell carcinoma with good prognosis, early pathological diagnosis analysis, can greatly improve the quality of life of the patients.%目的:探讨肾脏透明细胞癌的病理诊断分析。方法整群选取2011年1月-2014年6月在该病理科进行肾脏透明细胞癌的病理诊断的163例患者作为研究对象,并对其病理资料进行回顾性分析。结果163例患者中,肾透明细胞癌玉级56例,占34.4%,肾透明细胞癌Ⅱ级43例,占26.4%,肾透明细胞芋级35例,占21.5%,肾透明细胞癌Ⅳ级29例,占17.7%。镜下可见肿瘤细胞体积较大,圆形或多边形,胞质丰富,透明状,间质富有毛细血管和血窦。结论病理诊断是在镜下观察组织结构和细胞病变特征而做出的疾病诊断,肾脏透明细胞癌是肾癌中最常见的恶性肿瘤,预后较好,及早进行病理诊断分析,可以大大的提高患者的生活质量。

  12. B-cell and T-cell lymphomas of the breast: clinical--pathological features of 53 cases.

    Science.gov (United States)

    Gualco, Gabriela; Bacchi, Carlos E

    2008-10-01

    Breast involvement by non-Hodgkin lymphomas is rare. We studied the morphological, immunophenotypical, and clinical features of 53 cases of malignant lymphomas involving the breast in a population of Brazilian patients. Most of the cases were of B-cell phenotype. Four of the patients with primary breast lymphomas had T-cell lymphomas, 3 had CD30-positive anaplastic large cell lymphomas, and 1 had panniculitis-like T-cell lymphoma. Most patients presented with an incidental breast mass. Secondary breast lymphoma was seen in 19 patients and most commonly occurred as part of widespread nodal disease. Two patients presented with bilateral breast involvement. The most prevalent histological subtype was also diffuse large B-cell lymphoma, followed by follicular lymphoma. This study shows that the broad morphological and immunophenotypical spectrum of malignant lymphoma of the breast occurring in a large series of Brazilian patients has many similarities with that seen in Western countries, with a higher proportion of high-grade lymphomas in both primary and secondary cases.

  13. Mechanical Stress Promotes Cisplatin-Induced Hepatocellular Carcinoma Cell Death

    Directory of Open Access Journals (Sweden)

    Laila Ziko

    2015-01-01

    Full Text Available Cisplatin (CisPt is a commonly used platinum-based chemotherapeutic agent. Its efficacy is limited due to drug resistance and multiple side effects, thereby warranting a new approach to improving the pharmacological effect of CisPt. A newly developed mathematical hypothesis suggested that mechanical loading, when coupled with a chemotherapeutic drug such as CisPt and immune cells, would boost tumor cell death. The current study investigated the aforementioned mathematical hypothesis by exposing human hepatocellular liver carcinoma (HepG2 cells to CisPt, peripheral blood mononuclear cells, and mechanical stress individually and in combination. HepG2 cells were also treated with a mixture of CisPt and carnosine with and without mechanical stress to examine one possible mechanism employed by mechanical stress to enhance CisPt effects. Carnosine is a dipeptide that reportedly sequesters platinum-based drugs away from their pharmacological target-site. Mechanical stress was achieved using an orbital shaker that produced 300 rpm with a horizontal circular motion. Our results demonstrated that mechanical stress promoted CisPt-induced death of HepG2 cells (~35% more cell death. Moreover, results showed that CisPt-induced death was compromised when CisPt was left to mix with carnosine 24 hours preceding treatment. Mechanical stress, however, ameliorated cell death (20% more cell death.

  14. [Clinical pathology].

    Science.gov (United States)

    Dimitrijević, Jovan

    2006-05-01

    This work describes the basic elements of pathology used in clinical practice. Pathology plays an important role in clinical and scientific work, but only a few areas of pathology will be covered. Although the contribution of oncological and surgical pathology to therapy is the most well known, the cases chosen here will involve infectious pathology, diseases of the kidney and the liver, autoimmune diseases, as well as organ transplantation. Especially important is the description of methods that enable more accurate morphological diagnoses, such as histochemistry, immunohistochemistry, immunofluorescence, and electronic microscopy. Previous experience and joint work with clinical doctors have enabled the definition of significant morphological elements as well as of essential methods of pathohistological diagnosis. Besides, as is often the case, although disease symptoms are difficult to discern and biochemical results do not show significant changes compared to normal values, the results of biopsy come as a surprise to clinical doctors. For example, in virus hepatitis B involving so-called asymptomatic HBsAg carriers, we discovered every morphological form of hepatitis, from minimal lesions to chronic, persistent, and active hepatitis. With hepatitis C, certain morphological lesions point to the etiopathogenesis of this disease and thus help to confirm the diagnosis and to instigate therapy on time. Another significant experience involves kidney biopsies in cases when clinical findings are asymptomatic. Often, in such cases, morphological findings point to glomerulonephritis and glomerulopathy at different stages. Timely and subtle morphological diagnostics offer a more precise explanation for the pathological injury of tissues than other diagnostic methods. In this way, by adopting new methods, the work of pathologists is included more and more in everyday clinical practice. The inclusion of pathologists in a transplantation team makes sure a proper selection of

  15. Pineal Diffuse Large B-Cell Lymphoma Concomitant With Pituitary Prolactinoma: Possible Correlation Between 2 Distinguished Pathologies: A Case Report.

    Science.gov (United States)

    Kim, Yeong-Jin; Kim, Hee Kyung; Yang, Deok-Hwan; Jung, Shin; Noh, Myung-Giun; Lee, Jae-Hyuk; Lee, Kyung-Hwa; Moon, Kyung-Sub

    2016-02-01

    This is the first reported case of pineal lymphoma with concomitant prolactin-producing pituitary adenoma.A 51-year-old male experienced worsening headaches accompanied by nausea, diplopia, and memory loss for 1 month. Cranial nerve examination revealed bilateral upward gaze limitation with convergence impairment, which is known as Parinaud syndrome. Magnetic resonance images revealed a mass in the pineal gland with a coexisting mass within the enlarged sella fossa. Hormone analysis revealed hyperprolactinemia. The pineal mass was removed without injuring the hypothalamus, brain stem, or any neighboring vessels. Pathology examination confirmed the diagnosis of diffuse large B-cell lymphoma (DLBCL) involving the pineal gland. After further studies, the pineal lymphoma was determined to be a secondary tumor from a gastric primary tumor. The patient died 6 months after diagnosis due to systemic progression of DLBCL.Although the mechanistic link between hyperprolactinemia and lymphoma progression has not been clarified on a clinical basis, high prolactin levels may contribute to the rapid progression and therapeutic resistance of the lymphoma. PMID:26937937

  16. Pineal Diffuse Large B-Cell Lymphoma Concomitant With Pituitary Prolactinoma: Possible Correlation Between 2 Distinguished Pathologies

    Science.gov (United States)

    Kim, Yeong-Jin; Kim, Hee Kyung; Yang, Deok-Hwan; Jung, Shin; Noh, Myung-Giun; Lee, Jae-Hyuk; Lee, Kyung-Hwa; Moon, Kyung-Sub

    2016-01-01

    Abstract This is the first reported case of pineal lymphoma with concomitant prolactin-producing pituitary adenoma. A 51-year-old male experienced worsening headaches accompanied by nausea, diplopia, and memory loss for 1 month. Cranial nerve examination revealed bilateral upward gaze limitation with convergence impairment, which is known as Parinaud syndrome. Magnetic resonance images revealed a mass in the pineal gland with a coexisting mass within the enlarged sella fossa. Hormone analysis revealed hyperprolactinemia. The pineal mass was removed without injuring the hypothalamus, brain stem, or any neighboring vessels. Pathology examination confirmed the diagnosis of diffuse large B-cell lymphoma (DLBCL) involving the pineal gland. After further studies, the pineal lymphoma was determined to be a secondary tumor from a gastric primary tumor. The patient died 6 months after diagnosis due to systemic progression of DLBCL. Although the mechanistic link between hyperprolactinemia and lymphoma progression has not been clarified on a clinical basis, high prolactin levels may contribute to the rapid progression and therapeutic resistance of the lymphoma. PMID:26937937

  17. Resveratrol Protects against High-Fat Diet Induced Renal Pathological Damage and Cell Senescence by Activating SIRT1.

    Science.gov (United States)

    Zhang, Nannan; Li, Zhongchi; Xu, Kang; Wang, Yanying; Wang, Zhao

    2016-01-01

    Obesity-related renal diseases have been a worldwide issue. Effective strategy that prevents high fat-diet induced renal damage is of great significance. Resveratrol, a natural plant polyphenol, is famous for its antioxidant activity, cardioprotective effects and anticancer properties. However whether resveratrol can play a role in the treatment of renal diseases is unknown. In this study, we added resveratrol in normal glucose or high glucose medium and provide evidences that resveratrol protects against high-glucose triggered oxidative stress and cell senescence. Moreover, mice were fed with standard diet, standard diet plus resveratrol, high-fat diet or high-fat diet plus resveratrol for 3 months, and results show that resveratrol treatment prevents high-fat diet induced renal pathological damage by activating SIRT1, a key member in the mammalian sirtuin family that response to calorie restriction life-extension method. This research confirms the potential role of resveratrol in the treatment of renal diseases and may provide an effective and convenient method to mimic the beneficial effects of calorie restriction. PMID:27582325

  18. Pineal Diffuse Large B-Cell Lymphoma Concomitant With Pituitary Prolactinoma: Possible Correlation Between 2 Distinguished Pathologies: A Case Report.

    Science.gov (United States)

    Kim, Yeong-Jin; Kim, Hee Kyung; Yang, Deok-Hwan; Jung, Shin; Noh, Myung-Giun; Lee, Jae-Hyuk; Lee, Kyung-Hwa; Moon, Kyung-Sub

    2016-02-01

    This is the first reported case of pineal lymphoma with concomitant prolactin-producing pituitary adenoma.A 51-year-old male experienced worsening headaches accompanied by nausea, diplopia, and memory loss for 1 month. Cranial nerve examination revealed bilateral upward gaze limitation with convergence impairment, which is known as Parinaud syndrome. Magnetic resonance images revealed a mass in the pineal gland with a coexisting mass within the enlarged sella fossa. Hormone analysis revealed hyperprolactinemia. The pineal mass was removed without injuring the hypothalamus, brain stem, or any neighboring vessels. Pathology examination confirmed the diagnosis of diffuse large B-cell lymphoma (DLBCL) involving the pineal gland. After further studies, the pineal lymphoma was determined to be a secondary tumor from a gastric primary tumor. The patient died 6 months after diagnosis due to systemic progression of DLBCL.Although the mechanistic link between hyperprolactinemia and lymphoma progression has not been clarified on a clinical basis, high prolactin levels may contribute to the rapid progression and therapeutic resistance of the lymphoma.

  19. The Use of Human Adipose-Derived Stem Cells in the Treatment of Physiological and Pathological Vulvar Dystrophies

    Directory of Open Access Journals (Sweden)

    Maria Giuseppina Onesti

    2016-01-01

    Full Text Available “Vulvar dystrophy” is characterized by chronic alterations of vulvar trophism, occurring in both physiological (menopause and pathological (lichen sclerosus, vulvar graft-versus-host disease conditions. Associated symptoms are itching, burning, dyspareunia and vaginal dryness. Current treatments often do not imply a complete remission of symptoms. Adipose-Derived Stem Cells (ADSCs injection represents a valid alternative therapy to enhance trophism and tone of dystrophic tissues. We evaluated efficacy of ADSCs-based therapy in the dystrophic areas. From February to April 2013 we enrolled 8 patients with vulvar dystrophy. A biopsy specimen was performed before and after treatment. Digital photographs were taken at baseline and during the follow-up. Pain was detected with Visual Analogue Scale and sexual function was evaluated with Female Sexual Function Index. All patients received 2 treatments in 3 months. Follow-up was at 1 week , 1 and 3 months, and 1 and 2 years. We obtained a significant vulvar trophism enhancement in all patients, who reported pain reduction and sexual function improvement. Objective exam with speculum was easy to perform after treatment. We believe ADSCs-based therapy finds its application in the treatment of vulvar dystrophies, since ADSCs could induce increased vascularization due to their angiogenic properties and tissue trophism improvement thanks to their eutrophic effect.

  20. Prognostic significance of telomeric repeat length alterations in pathological stage I-IIIA non-small cell lung cancer.

    Science.gov (United States)

    Hirashima, T; Komiya, T; Nitta, T; Takada, Y; Kobayashi, M; Masuda, N; Matui, K; Takada, M; Kikui, M; Yasumitu, T; Ohno, A; Nakagawa, K; Fukuoka, M; Kawase, I

    2000-01-01

    This study was performed to evaluate the prognostic significance of alteration in telomere length in pathological stage (p-stage) I-IIIA non-small cell lung cancer (NSCLC). Paired cancer and normal lung tissues were obtained from 72 patients with histologically confirmed p-stage I-IIIA NSCLC. Terminal restriction fragment (TRF) length, which indicates telomere length, was measured by Southern blot analysis. Tumor telomerase activity was also assayed by non-radioactive PCR-ELISA in 55 patients. TRF length (mean +/- SD) in normal tissue was 6.2 +/- 1.1 Kb. Therefore, upper and lower limits of normal range in TRF length was set at 8.4 (mean + 2SD) Kb and 4.0 (mean-2SD) Kb, respectively. A tumor showing TRF length over normal range was defined as positive for the alteration. In 72 patients, 25 (34.7%) with alteration in TRF length had significantly shorter survival durations than those of the others. Telomerase activity did not correlate with survival duration. In multivariate analysis, alteration in TRF length (P = 0.0033) was second to p-stage (P = 0.0004) in importance among the various parameters.

  1. The Interplay between Cell Wall Mechanical Properties and the Cell Cycle in Staphylococcus aureus

    OpenAIRE

    Bailey, Richard G.; Turner, Robert D.; Mullin, Nic; Clarke, Nigel,; Foster, Simon J.; Hobbs, Jamie K.

    2014-01-01

    The nanoscale mechanical properties of live Staphylococcus aureus cells during different phases of growth were studied by atomic force microscopy. Indentation to different depths provided access to both local cell wall mechanical properties and whole-cell properties, including a component related to cell turgor pressure. Local cell wall properties were found to change in a characteristic manner throughout the division cycle. Splitting of the cell into two daughter cells followed a local softe...

  2. Derivation of cochlear cells from pathological or isogenic human iPSCs for modeling hereditary hearing loss

    OpenAIRE

    Czajkowski, Amandine; Grobarczyk, Benjamin; Hanon, Kevin; Lefebvre, Philippe; Delacroix, Laurence; Malgrange, Brigitte

    2016-01-01

    Alström Syndrome (AS) is a human autosomal recessive genetic disorder characterized by numerous clinical symptoms including deafness. AS is caused by mutations in the ALMS1 gene encoding for ALMS1 protein expressed at the basal body and implicated in ciliogenesis, cell cycle and proliferation (Jagger et al., 2011; Zulato et al., 2011 & Shenje et al., 2014). We are interesting in understanding the unknown mechanisms involving this protein in the genetic deafness of AS patients. To develop a m...

  3. Abnormal Calcium Handling Properties Underlie Familial Hypertrophic Cardiomyopathy Pathology in Patient-Specific Induced Pluripotent Stem Cells

    OpenAIRE

    Lan, Feng; Lee, Andrew S.; Liang, Ping; Sanchez-Freire, Veronica; Nguyen, Patricia K; Wang, Li; Han, Leng; Yen, Michelle; Wang, Yongming; Sun, Ning; Abilez, Oscar J.; Hu, Shijun; Ebert, Antje D.; Navarrete, Enrique G.; Simmons, Chelsey S.

    2013-01-01

    Familial hypertrophic cardiomyopathy (HCM) is a prevalent hereditary cardiac disorder linked to arrhythmia and sudden cardiac death. While the causes of HCM have been identified as genetic mutations in the cardiac sarcomere, the pathways by which sarcomeric mutations engender myocyte hypertrophy and electrophysiological abnormalities are not understood. To elucidate the mechanisms underlying HCM development, we generated patient-specific induced pluripotent stem cell cardiomyocytes (iPSC-CMs)...

  4. The pathological changes of inflammatory cells,smooth muscle cell and neo-vessels in the vulnerable carotid atherosclerosis plaque

    Institute of Scientific and Technical Information of China (English)

    吕鹤

    2006-01-01

    Objective To study the inflammation, smooth muscle cells and neovessels change in the vulnerable carotid atherosclerosis plaque. Methods 6 male patients, aged between 66~73 years old, had the history of stroke or transient cerebral ischemic attacks of internal carotid artery system in a few days to 5 months. MRI and DSA re-

  5. Mechanical properties of normal versus cancerous breast cells.

    Science.gov (United States)

    Smelser, Amanda M; Macosko, Jed C; O'Dell, Adam P; Smyre, Scott; Bonin, Keith; Holzwarth, George

    2015-11-01

    A cell's mechanical properties are important in determining its adhesion, migration, and response to the mechanical properties of its microenvironment and may help explain behavioral differences between normal and cancerous cells. Using fluorescently labeled peroxisomes as microrheological probes, the interior mechanical properties of normal breast cells were compared to a metastatic breast cell line, MDA-MB-231. To estimate the mechanical properties of cell cytoplasms from the motions of their peroxisomes, it was necessary to reduce the contribution of active cytoskeletal motions to peroxisome motion. This was done by treating the cells with blebbistatin, to inhibit myosin II, or with sodium azide and 2-deoxy-D-glucose, to reduce intracellular ATP. Using either treatment, the peroxisomes exhibited normal diffusion or subdiffusion, and their mean squared displacements (MSDs) showed that the MDA-MB-231 cells were significantly softer than normal cells. For these two cell types, peroxisome MSDs in treated and untreated cells converged at high frequencies, indicating that cytoskeletal structure was not altered by the drug treatment. The MSDs from ATP-depleted cells were analyzed by the generalized Stokes-Einstein relation to estimate the interior viscoelastic modulus G* and its components, the elastic shear modulus G' and viscous shear modulus G", at angular frequencies between 0.126 and 628 rad/s. These moduli are the material coefficients that enter into stress-strain relations and relaxation times in quantitative mechanical models such as the poroelastic model of the interior regions of cancerous and non-cancerous cells. PMID:25929519

  6. Cellular pressure and volume regulation and implications for cell mechanics.

    Science.gov (United States)

    Jiang, Hongyuan; Sun, Sean X

    2013-08-01

    In eukaryotic cells, small changes in cell volume can serve as important signals for cell proliferation, death, and migration. Volume and shape regulation also directly impacts the mechanics of cells and tissues. Here, we develop a mathematical model of cellular volume and pressure regulation, incorporating essential elements such as water permeation, mechanosensitive channels, active ion pumps, and active stresses in the cortex. The model can fully explain recent experimental data, and it predicts cellular volume and pressure for several models of cell cortical mechanics. Moreover, we show that when cells are subjected to an externally applied load, such as in an atomic force microscopy indentation experiment, active regulation of volume and pressure leads to a complex cellular response. Instead of the passive mechanics of the cortex, the observed cell stiffness depends on several factors working together. This provides a mathematical explanation of rate-dependent response of cells under force. PMID:23931309

  7. Cell Death Mechanisms Induced by Cytotoxic Lymphocytes

    Institute of Scientific and Technical Information of China (English)

    Ch(a)vez-Gal(a)n L; Arenas-Del Angel MC; Zenteno E; Ch(a)vez R; Lascurain R

    2009-01-01

    One of the functions of the immune system is to recognize and destroy abnormal or infected cells to maintain homeostasis. This is accomplished by cytotoxic lymphocytes. Cytotoxicity is a highly organized multifactor process. Here, we reviewed the apoptosis pathways induced by the two main cytotoxic lymphocyte subsets, natural killer (NK) cells and CD8+T cells. In base to recent experimental evidence, we reviewed NK receptors involved in recognition of target-cell, as well as lytic molecules such as perforin, granzymes-A and -B, and granulysin. In addition, we reviewed the Fas-FasL intercellular linkage mediated pathway, and briefly the cross-linking of tumor necrosis factor (TNF) and TNF receptor pathway. We discussed three models of possible molecular interaction between lyric molecules from effector cytotoxic cells and target-cell membrane to induction of apoptosis.

  8. Lymphoid Cell-Glioma Cell Interaction Enhances Cell Coat Production by Human Gliomas: Novel Suppressor Mechanism

    Science.gov (United States)

    Dick, Steven J.; Macchi, Beatrice; Papazoglou, Savvas; Oldfield, Edward H.; Kornblith, Paul L.; Smith, Barry H.; Gately, Maurice K.

    1983-05-01

    Certain human glioma lines produce mucopolysaccharide coats that impair the generation of cytolytic lymphocytes in response to these lines in vitro. Coat production is substantially enhanced by the interaction of glioma cells with a macromolecular factor released by human peripheral blood mononuclear cells in culture. This interaction thus constitutes an unusual mechanism by which inflammatory cells may nonspecifically suppress the cellular immune response to at least one class of solid tumors in humans.

  9. Cell death signalling mechanisms in heart failure

    OpenAIRE

    Mughal, Wajihah; Kirshenbaum, Lorrie A.

    2011-01-01

    In 2003, cardiovascular disease was the most costly disease in Canada, and it is still on the rise. The loss of properly functioning cardiomyocytes leads to cardiac impairment, which is a consequence of heart failure. Therefore, understanding the pathways of cell death (necrosis and apoptosis) has potential implications for the development of therapeutic strategies. In addition, the role of B-cell lymphoma-2 family members is discussed and the importance of mitochondria in directing cell deat...

  10. Fluoride inhibits the response of bone cells to mechanical loading

    NARCIS (Netherlands)

    H.M.E. Willems; E.G.H.M. van den Heuvel; S. Castelein; J. Keverling Buisman; A.L.J.J. Bronckers; A.D. Bakker; J. Klein-Nulend

    2011-01-01

    The response of bone cells to mechanical loading is mediated by the cytoskeleton. Since the bone anabolic agent fluoride disrupts the cytoskeleton, we investigated whether fluoride affects the response of bone cells to mechanical loading, and whether this is cytoskeleton mediated. The mechano-respon

  11. Parkinson's disease: Studies on the pathology of the disease and the mechanism of action of the neurotoxin MPTP

    Energy Technology Data Exchange (ETDEWEB)

    D' Amato, R.J.

    1988-01-01

    In humans and animals, exposure to 1-methyl-4-phenyl-1,2,3,6-tetra-hydropyridine (MPTP) causes certain clinical, pathological, and neurochemical features of Parkinson's disease (PD). MPTP is metabolized in the brain by monoamine oxidase (MAOb) to 1-methyl-4-phenylpyridine (MPP{sup +}), which is selectively accumulated and concentrated by high affinity uptake mechanisms into catecholamine neurons. We have demonstrated high affinity binding of MPP{sup +} to neuromelanin which may result in a toxic intraneuronal sequestration of MPP{sup +}. The involvement of neuromelanin is further supported by the demonstration that monkeys pretreated with chloroquine prior to the administration of MPTP are protected from MPTP induced neurotoxicity. Decreases in serotonin levels have been reported in the brains and spinal fluid of patients with both Parkinson's and Alzheimer's disease. In an effort to investigate the pathology of serotonin neurons in postmortem brain tissue from Parkinson's and Alzheimer's patients, ({sup 3}H)citalopram was characterized as a means of labeling serotonin uptake sites present on serotonin terminals.

  12. Expression of Yes-associated protein in non-small cell lung cancer and its relationship with clinical pathological factors

    Institute of Scientific and Technical Information of China (English)

    SU Li-li; MA Wei-xia; YUAN Jian-feng; SHAO Yang; XIAO Wei; JIANG Shu-juan

    2012-01-01

    Background Yes-associated protein(YAP)plays an important role in signal transduction and gene transcription regulation in normal cells,with elevated and over-expressed YAP levels observed in various malignant tumors.The aim of this study was to investigate the expression of YAP in non-small cell lung cancer(NSCLC),and to study the possible relationship of YAP expression with the occurrence and development of NSCLC.Methods YAP expression was assessed in 40 cases of NSCLC tumor tissues by immunohistochemistry,and their protein and mRNA levels were evaluated through Western blotting and reverse transcription-polymerase chain reaction(PCR),respectively.Normal lung tissues obtained from the same patient were used as control.Statistical analysis was performed to correlate the YAP expression to clinical pathological factors,such as tumor type,stage and grade.Results YAP-positive expression was found in 28(70%)of the 40 cases of NSCLC,which included 10 cases of squamous cell carcinoma(25%),17 cases of adenocarcinoma(42.5%)and 1 case of squamous adenocarcinoma(2.5%).In the 28 YAP-positive cases,19 cases showed lymph node metastasis and were classified in TNM stage Ⅱ+Ⅲ(47.5%);the other nine cases showed no lymph node metastasis(22.5%)and were classified in the TNM stage Ⅰ.There was no relationship between YAP expression and patients'age,gender or tumor histological grades.However,YAP showed significant over expression in late period of T stage(P=0.012),TNM stage(P=0.039),and lymph node metastasis(P=0.013),respectively.Notably,YAP-positive expression was significantly higher in adenocarcinoma than that in squamous cell carcinoma(P=0.041).Conclusions Over-expression of YAP was associated with NSCLC,especially lung adenocarcinoma.The high YAP expression in late period of tumor stage and lymph node metastasis may indicate that YAP expression could be an early marker for NSCLC tumorigenesis.

  13. Treatment Resistance Mechanisms of Malignant Glioma Tumor Stem Cells

    International Nuclear Information System (INIS)

    Malignant gliomas are highly lethal because of their resistance to conventional treatments. Recent evidence suggests that a minor subpopulation of cells with stem cell properties reside within these tumors. These tumor stem cells are more resistant to radiation and chemotherapies than their counterpart differentiated tumor cells and may underlie the persistence and recurrence of tumors following treatment. The various mechanisms by which tumor stem cells avoid or repair the damaging effects of cancer therapies are discussed

  14. Treatment Resistance Mechanisms of Malignant Glioma Tumor Stem Cells

    Energy Technology Data Exchange (ETDEWEB)

    Schmalz, Philip G.R. [Surgical and Molecular Neuro-Oncology Unit, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892 (United States); Howard Hughes Medical Institute, National Institutes of Health Research Scholars Program, Bethesda, MD 20892 (United States); Shen, Michael J.; Park, John K., E-mail: parkjk@ninds.nih.gov [Surgical and Molecular Neuro-Oncology Unit, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892 (United States)

    2011-02-10

    Malignant gliomas are highly lethal because of their resistance to conventional treatments. Recent evidence suggests that a minor subpopulation of cells with stem cell properties reside within these tumors. These tumor stem cells are more resistant to radiation and chemotherapies than their counterpart differentiated tumor cells and may underlie the persistence and recurrence of tumors following treatment. The various mechanisms by which tumor stem cells avoid or repair the damaging effects of cancer therapies are discussed.

  15. Combined gene/cell therapies provide long-term and pervasive rescue of multiple pathological symptoms in a murine model of globoid cell leukodystrophy.

    Science.gov (United States)

    Ricca, Alessandra; Rufo, Nicole; Ungari, Silvia; Morena, Francesco; Martino, Sabata; Kulik, Wilem; Alberizzi, Valeria; Bolino, Alessandra; Bianchi, Francesca; Del Carro, Ubaldo; Biffi, Alessandra; Gritti, Angela

    2015-06-15

    Globoid cell leukodystrophy (GLD) is a lysosomal storage disease caused by deficient activity of β-galactocerebrosidase (GALC). The infantile forms manifest with rapid and progressive central and peripheral demyelination, which represent a major hurdle for any treatment approach. We demonstrate here that neonatal lentiviral vector-mediated intracerebral gene therapy (IC GT) or transplantation of GALC-overexpressing neural stem cells (NSC) synergize with bone marrow transplant (BMT) providing dramatic extension of lifespan and global clinical-pathological rescue in a relevant GLD murine model. We show that timely and long-lasting delivery of functional GALC in affected tissues ensured by the exclusive complementary mode of action of the treatments underlies the outstanding benefit. In particular, the contribution of neural stem cell transplantation and IC GT during the early asymptomatic stage of the disease is instrumental to enhance long-term advantage upon BMT. We clarify the input of central nervous system, peripheral nervous system and periphery to the disease, and the relative contribution of treatments to the final therapeutic outcome, with important implications for treatment strategies to be tried in human patients. This study gives proof-of-concept of efficacy, tolerability and clinical relevance of the combined gene/cell therapies proposed here, which may constitute a feasible and effective therapeutic opportunity for children affected by GLD. PMID:25749991

  16. Engineering three-dimensional cell mechanical microenvironment with hydrogels.

    Science.gov (United States)

    Huang, Guoyou; Wang, Lin; Wang, Shuqi; Han, Yulong; Wu, Jinhui; Zhang, Qiancheng; Xu, Feng; Lu, Tian Jian

    2012-12-01

    Cell mechanical microenvironment (CMM) significantly affects cell behaviors such as spreading, migration, proliferation and differentiation. However, most studies on cell response to mechanical stimulation are based on two-dimensional (2D) planar substrates, which cannot mimic native three-dimensional (3D) CMM. Accumulating evidence has shown that there is a significant difference in cell behavior in 2D and 3D microenvironments. Among the materials used for engineering 3D CMM, hydrogels have gained increasing attention due to their tunable properties (e.g. chemical and mechanical properties). In this paper, we provide an overview of recent advances in engineering hydrogel-based 3D CMM. Effects of mechanical cues (e.g. hydrogel stiffness and externally induced stress/strain in hydrogels) on cell behaviors are described. A variety of approaches to load mechanical stimuli in 3D hydrogel-based constructs are also discussed.

  17. Non-invasive in Situ Simultaneous Measurement of Multi-parameter Mechanical Properties of Red Blood Cell Membrane

    Institute of Scientific and Technical Information of China (English)

    Jing LI; Yao-Xiong HUANG; Tao JI; Mei TU; Xuan MAO; Wen-Xin CHEN; Guang-Wei CHEN

    2005-01-01

    The purpose of this study was to develop a new dynamic image analyzing technique that will give us the ability to measure the viscoelastic parameters of individual living red blood cells non-invasively, in situ and in real time. With this technique, the bending modulus Kc, the shear elasticityμ and their ratio ε were measured under different temperatures, oxygen partial pressures and osmotic pressures. The results not only show the effects of external conditions on mechanical properties of cell membranes including deformability,flexibility, adhesive ability and plasticity, but also demonstrate that the technique can be used to measure cell membrane parameters continuously under several physiological and pathological conditions.

  18. Mechanisms of regulating cell topology in proliferating epithelia: impact of division plane, mechanical forces, and cell memory.

    Directory of Open Access Journals (Sweden)

    Yingzi Li

    Full Text Available Regulation of cell growth and cell division has a fundamental role in tissue formation, organ development, and cancer progression. Remarkable similarities in the topological distributions were found in a variety of proliferating epithelia in both animals and plants. At the same time, there are species with significantly varied frequency of hexagonal cells. Moreover, local topology has been shown to be disturbed on the boundary between proliferating and quiescent cells, where cells have fewer sides than natural proliferating epithelia. The mechanisms of regulating these topological changes remain poorly understood. In this study, we use a mechanical model to examine the effects of orientation of division plane, differential proliferation, and mechanical forces on animal epithelial cells. We find that regardless of orientation of division plane, our model can reproduce the commonly observed topological distributions of cells in natural proliferating animal epithelia with the consideration of cell rearrangements. In addition, with different schemes of division plane, we are able to generate different frequency of hexagonal cells, which is consistent with experimental observations. In proliferating cells interfacing quiescent cells, our results show that differential proliferation alone is insufficient to reproduce the local changes in cell topology. Rather, increased tension on the boundary, in conjunction with differential proliferation, can reproduce the observed topological changes. We conclude that both division plane orientation and mechanical forces play important roles in cell topology in animal proliferating epithelia. Moreover, cell memory is also essential for generating specific topological distributions.

  19. Mechanisms of regulating cell topology in proliferating epithelia: impact of division plane, mechanical forces, and cell memory.

    Science.gov (United States)

    Li, Yingzi; Naveed, Hammad; Kachalo, Sema; Xu, Lisa X; Liang, Jie

    2012-01-01

    Regulation of cell growth and cell division has a fundamental role in tissue formation, organ development, and cancer progression. Remarkable similarities in the topological distributions were found in a variety of proliferating epithelia in both animals and plants. At the same time, there are species with significantly varied frequency of hexagonal cells. Moreover, local topology has been shown to be disturbed on the boundary between proliferating and quiescent cells, where cells have fewer sides than natural proliferating epithelia. The mechanisms of regulating these topological changes remain poorly understood. In this study, we use a mechanical model to examine the effects of orientation of division plane, differential proliferation, and mechanical forces on animal epithelial cells. We find that regardless of orientation of division plane, our model can reproduce the commonly observed topological distributions of cells in natural proliferating animal epithelia with the consideration of cell rearrangements. In addition, with different schemes of division plane, we are able to generate different frequency of hexagonal cells, which is consistent with experimental observations. In proliferating cells interfacing quiescent cells, our results show that differential proliferation alone is insufficient to reproduce the local changes in cell topology. Rather, increased tension on the boundary, in conjunction with differential proliferation, can reproduce the observed topological changes. We conclude that both division plane orientation and mechanical forces play important roles in cell topology in animal proliferating epithelia. Moreover, cell memory is also essential for generating specific topological distributions.

  20. Do mechanical strain and TNF-α interact to amplify pro-inflammatory cytokine production in human annulus fibrosus cells?

    Science.gov (United States)

    Likhitpanichkul, Morakot; Torre, Olivia M; Gruen, Jadry; Walter, Benjamin A; Hecht, Andrew C; Iatridis, James C

    2016-05-01

    During intervertebral disc (IVD) injury and degeneration, annulus fibrosus (AF) cells experience large mechanical strains in a pro-inflammatory milieu. We hypothesized that TNF-α, an initiator of IVD inflammation, modifies AF cell mechanobiology via cytoskeletal changes, and interacts with mechanical strain to enhance pro-inflammatory cytokine production. Human AF cells (N=5, Thompson grades 2-4) were stretched uniaxially on collagen-I coated chambers to 0%, 5% (physiological) or 15% (pathologic) strains at 0.5Hz for 24h under hypoxic conditions with or without TNF-α (10ng/mL). AF cells were treated with anti-TNF-α and anti-IL-6. ELISA assessed IL-1β, IL-6, and IL-8 production and immunocytochemistry measured F-actin, vinculin and α-tubulin in AF cells. TNF-α significantly increased AF cell pro-inflammatory cytokine production compared to basal conditions (IL-1β:2.0±1.4-84.0±77.3, IL-6:10.6±9.9-280.9±214.1, IL-8:23.9±26.0-5125.1±4170.8pg/ml for basal and TNF-α treatment, respectively) as expected, but mechanical strain did not. Pathologic strain in combination with TNF-α increased IL-1β, and IL-8 but not IL-6 production of AF cells. TNF-α treatment altered F-actin and α-tubulin in AF cells, suggestive of altered cytoskeletal stiffness. Anti-TNF-α (infliximab) significantly inhibited pro-inflammatory cytokine production while anti-IL-6 (atlizumab) did not. In conclusion, TNF-α altered AF cell mechanobiology with cytoskeletal remodeling that potentially sensitized AF cells to mechanical strain and increased TNF-α-induced pro-inflammatory cytokine production. Results suggest an interaction between TNF-α and mechanical strain and future mechanistic studies are required to validate these observations.

  1. Down-regulation of adipogenesis of mesenchymal stem cells by oscillating high-gradient magnetic fields and mechanical vibration

    Science.gov (United States)

    Zablotskii, V.; Lunov, O.; Novotná, B.; Churpita, O.; Trošan, P.; HoláÅ, V.; Syková, E.; Dejneka, A.; Kubinová, Š.

    2014-09-01

    Nowadays, the focus in medicine on molecular genetics has resulted in a disregard for the physical basis of treatment even though many diseases originate from changes in cellular mechanics. Perturbations of the cellular nanomechanics promote pathologies, including cardiovascular disease and cancer. Furthermore, whilst the biological and therapeutic effects of magnetic fields are a well-established fact, to date the underlying mechanisms remain obscure. Here, we show that oscillating high-gradient magnetic field (HGMF) and mechanical vibration affect adipogenic differentiation of mesenchymal stem cells by the transmission of mechanical stress to the cell cytoskeleton, resulting in F-actin remodelling and subsequent down-regulation of adipogenic genes adiponectin, PPARγ, and AP2. Our findings propose an insight into the regulation of cellular nanomechanics, and provide a basis for better controlled down-regulation of stem cell adipogenesis by HGMF, which may facilitate the development of challenging therapeutic strategies suitable for the remote control of biological systems.

  2. [Researches on mechanism of cell toxicity caused by niclosamide].

    Science.gov (United States)

    Xu, Ying; Dai, Jian-rong

    2015-02-01

    Niclosamide is the most commonly used molluscicide. Along with a lot of application of niclosamide, more and more scientists studied its toxic effects to aquatic organisms as well as the related cell toxicity mechanism. This paper summarizes the toxicity on cell, organelle, enzyme, cell signaling pathway, and genetic material caused by niclosamide, and puts forward the future research direction. PMID:26094434

  3. Pathological Propagation through Cell-to-Cell Transmission of Non-Prion Protein Aggregates in Neurodegenerative Disorders

    Science.gov (United States)

    Lee, Seung-Jae; Desplats, Paula; Sigurdson, Christina; Tsigelny, Igor; Masliah, Eliezer

    2016-01-01

    Neurodegenerative disorders such as Alzheimer's Disease, Parkinson's Disease, fronto-temporal dementia, Huntington's Disease and Creutzfeldt-Jakob Disease (CJD) are characterized by progressive accumulation of protein aggregates in selected brain regions. Protein misfolding and templated assembly into aggregates might result from an imbalance between protein synthesis, aggregation and clearance. While protein misfolding and aggregation occur in most neurodegenerative disorders, the concept of spreading and infectivity of aggregates in the CNS has been reserved to prion diseases such as CJD and bovine spongiform encephalopathy. Emerging evidence suggests that prion-like spreading may occur in other neurodegenerative disorders, taking place with secreted proteins, such as amyloid-β,) and cytosolic proteins, such as tau, huntingtin and α-synuclein. Underlying molecular mechanisms and therapeutic implications are discussed. PMID:21045796

  4. Cardamonin, a Novel Antagonist of hTRPA1 Cation Channel, Reveals Therapeutic Mechanism of Pathological Pain

    Directory of Open Access Journals (Sweden)

    Shifeng Wang

    2016-08-01

    Full Text Available The increasing demand for safe and effective treatments of chronic pain has promoted the investigation of novel analgesic drugs. Some herbals have been known to be able to relieve pain, while the chemical basis and target involved in this process remained to be clarified. The current study aimed to find anti-nociceptive candidates targeting transient receptor potential ankyrin 1 (TRPA1, a receptor that implicates in hyperalgesia and neurogenic inflammation. In the current study, 156 chemicals were tested for blocking HEK293/TRPA1 ion channel by calcium-influx assay. Docking study was conducted to predict the binding modes of hit compound with TRPA1 using Discovery Studio. Cytotoxicity in HEK293 was conducted by Cell Titer-Glo assay. Additionally, cardiotoxicity was assessed via xCELLigence RTCA system. We uncovered that cardamonin selectively blocked TRPA1 activation while did not interact with TRPV1 nor TRPV4 channel. A concentration-dependent inhibitory effect was observed with IC50 of 454 nM. Docking analysis of cardamonin demonstrated a compatible interaction with A-967079-binding site of TRPA1. Meanwhile, cardamonin did not significantly reduce HEK293 cell viability, nor did it impair cardiomyocyte constriction. Our data suggest that cardamonin is a selective TRPA1 antagonist, providing novel insight into the target of its anti-nociceptive activity.

  5. ROS, Cell Senescence, and Novel Molecular Mechanisms in Aging and Age-Related Diseases

    Directory of Open Access Journals (Sweden)

    Pierpaola Davalli

    2016-01-01

    Full Text Available The aging process worsens the human body functions at multiple levels, thus causing its gradual decrease to resist stress, damage, and disease. Besides changes in gene expression and metabolic control, the aging rate has been associated with the production of high levels of Reactive Oxygen Species (ROS and/or Reactive Nitrosative Species (RNS. Specific increases of ROS level have been demonstrated as potentially critical for induction and maintenance of cell senescence process. Causal connection between ROS, aging, age-related pathologies, and cell senescence is studied intensely. Senescent cells have been proposed as a target for interventions to delay the aging and its related diseases or to improve the diseases treatment. Therapeutic interventions towards senescent cells might allow restoring the health and curing the diseases that share basal processes, rather than curing each disease in separate and symptomatic way. Here, we review observations on ROS ability of inducing cell senescence through novel mechanisms that underpin aging processes. Particular emphasis is addressed to the novel mechanisms of ROS involvement in epigenetic regulation of cell senescence and aging, with the aim to individuate specific pathways, which might promote healthy lifespan and improve aging.

  6. Modeling the mechanics of cells in the cell-spreading process driven by traction forces.

    Science.gov (United States)

    Fang, Yuqiang; Lai, King W C

    2016-04-01

    Mechanical properties of cells and their mechanical interaction with the extracellular environments are main factors influencing cellular function, thus indicating the progression of cells in different disease states. By considering the mechanical interactions between cell adhesion molecules and the extracellular environment, we developed a cell mechanical model that can characterize the mechanical changes in cells during cell spreading. A cell model was established that consisted of various main subcellular components, including cortical cytoskeleton, nuclear envelope, actin filaments, intermediate filaments, and microtubules. We demonstrated the structural changes in subcellular components and the changes in spreading areas during cell spreading driven by traction forces. The simulation of nanoindentation tests was conducted by integrating the indenting force to the cell model. The force-indentation curve of the cells at different spreading states was simulated, and the results showed that cell stiffness increased with increasing traction forces, which were consistent with the experimental results. The proposed cell mechanical model provides a strategy to investigate the mechanical interactions of cells with the extracellular environments through the adhesion molecules and to reveal the cell mechanical properties at the subcellular level as cells shift from the suspended state to the adherent state. PMID:27176326

  7. Mechanisms of daughter cell-size control during cell division.

    Science.gov (United States)

    Kiyomitsu, Tomomi

    2015-05-01

    Daughter cell size is tightly regulated during cell division. In animal cells, the position of the anaphase spindle specifies the cell cleavage site to dictate the relative size of the daughter cells. Although spindle orientation is regulated by dynein-dependent cortical pulling forces exerted on astral microtubules in many cell types, it was unclear how these forces are precisely regulated to center or displace the spindle. Recently, intrinsic signals derived from chromosomes or spindle poles have been demonstrated to regulate dynein-dependent pulling forces in symmetrically dividing cells. Unexpectedly, myosin-dependent contractile forces have also been shown to control spindle position by altering the cellular boundaries during anaphase. In this review, I discuss how dynein- and myosin-dependent forces are coordinately regulated to control daughter cell size. PMID:25548067

  8. Molecular mechanisms of bortezomib resistant adenocarcinoma cells.

    Directory of Open Access Journals (Sweden)

    Erika Suzuki

    Full Text Available Bortezomib (Velcade™ is a reversible proteasome inhibitor that is approved for the treatment of multiple myeloma (MM. Despite its demonstrated clinical success, some patients are deprived of treatment due to primary refractoriness or development of resistance during therapy. To investigate the role of the duration of proteasome inhibition in the anti-tumor response of bortezomib, we established clonal isolates of HT-29 adenocarcinoma cells adapted to continuous exposure of bortezomib. These cells were ~30-fold resistant to bortezomib. Two novel and distinct mutations in the β5 subunit, Cys63Phe, located distal to the binding site in a helix critical for drug binding, and Arg24Cys, found in the propeptide region were found in all resistant clones. The latter mutation is a natural variant found to be elevated in frequency in patients with MM. Proteasome activity and levels of both the constitutive and immunoproteasome were increased in resistant cells, which correlated to an increase in subunit gene expression. These changes correlated with a more rapid recovery of proteasome activity following brief exposure to bortezomib. Increased recovery rate was not due to increased proteasome turnover as similar findings were seen in cells co-treated with cycloheximide. When we exposed resistant cells to the irreversible proteasome inhibitor carfilzomib we noted a slower rate of recovery of proteasome activity as compared to bortezomib in both parental and resistant cells. Importantly, carfilzomib maintained its cytotoxic potential in the bortezomib resistant cell lines. Therefore, resistance to bortezomib, can be overcome with irreversible inhibitors, suggesting prolonged proteasome inhibition induces a more potent anti-tumor response.

  9. Mechanical property quantification of endothelial cells using scanning acoustic microscopy

    Science.gov (United States)

    Shelke, A.; Brand, S.; Kundu, T.; Bereiter-Hahn, J.; Blase, C.

    2012-04-01

    The mechanical properties of cells reflect dynamic changes of cellular organization which occur during physiologic activities like cell movement, cell volume regulation or cell division. Thus the study of cell mechanical properties can yield important information for understanding these physiologic activities. Endothelial cells form the thin inner lining of blood vessels in the cardiovascular system and are thus exposed to shear stress as well as tensile stress caused by the pulsatile blood flow. Endothelial dysfunction might occur due to reduced resistance to mechanical stress and is an initial step in the development of cardiovascular disease like, e.g., atherosclerosis. Therefore we investigated the mechanical properties of primary human endothelial cells (HUVEC) of different age using scanning acoustic microscopy at 1.2 GHz. The HUVECs are classified as young (tD 90 h) cells depending upon the generation time for the population doubling of the culture (tD). Longitudinal sound velocity and geometrical properties of cells (thickness) were determined using the material signature curve V(z) method for variable culture condition along spatial coordinates. The plane wave technique with normal incidence is assumed to solve two-dimensional wave equation. The size of the cells is modeled using multilayered (solid-fluid) system. The propagation of transversal wave and surface acoustic wave are neglected in soft matter analysis. The biomechanical properties of HUVEC cells are quantified in an age dependent manner.

  10. The Mechanisms of Plant Cell Wall Deconstruction during Enzymatic Hydrolysis

    OpenAIRE

    Thygesen, Lisbeth G; Thybring, Emil E.; Johansen, Katja S.; Claus Felby

    2014-01-01

    Mechanical agitation during enzymatic hydrolysis of insoluble plant biomass at high dry matter contents is indispensable for the initial liquefaction step in biorefining. It is known that particle size reduction is an important part of liquefaction, but the mechanisms involved are poorly understood. Here we put forward a simple model based on mechanical principles capable of capturing the result of the interaction between mechanical forces and cell wall weakening via hydrolysis of glucosidic ...

  11. Macrophages in Langerhans cell histiocytosis are differentiated toward M2 phenotype: their possible involvement in pathological processes.

    Science.gov (United States)

    Ohnishi, Koji; Komohara, Yoshihiro; Sakashita, Naomi; Iyama, Ken-Ichi; Murayama, Toshihiko; Takeya, Motohiro

    2010-01-01

    Although numerous macrophages are found in the lesions of Langerhans cell histiocytosis (LCH), their activation phenotypes and their roles in the disease process have not been clarified. Paraffin-embedded LCH samples were examined on immunohistochemistry and it was found that CD163 can be used to distinguish infiltrated macrophages from neoplastic Langerhans cells (LC). The number of CD163-positve macrophages was positively correlated with the number of multinucleated giant cells (MGC), indicating that most MGC are derived from infiltrated macrophages. A significant number of CD163-positive macrophages were positive for interleukin (IL)-10 and phospho-signal transducer and activator of transcription-3 (pSTAT3), an IL-10-induced signal transduction molecule. This indicates that these macrophages are polarized to anti-inflammatory macrophages of M2 phenotype. Tumor-derived macrophage-colony-stimulating factor (M-CSF) was considered to responsible for inducing M2 differentiation of infiltrated macrophages. The number of CD163-positive macrophages in different cases of LCH varied, and interestingly the density of CD163-positive macrophages was inversely correlated with the Ki-67-positivity of LC. Although the underlying mechanism is not fully elucidated, macrophage-derived IL-10 was considered to be involved in the suppression of tumor cell proliferation via activation of STAT3. PMID:20055949

  12. Mechanism of cell alignment in groups of Myxococcus xanthus bacteria

    Science.gov (United States)

    Balgam, Rajesh; Igoshin, Oleg

    2015-03-01

    Myxococcus xanthus is a model for studying self-organization in bacteria. These flexible cylindrical bacteria move along. In groups, M. xanthus cells align themselves into dynamic cell clusters but the mechanism underlying their formation is unknown. It has been shown that steric interactions can cause alignment in self-propelled hard rods but it is not clear how flexibility and reversals affect the alignment and cluster formation. We have investigated cell alignment process using our biophysical model of M. xanthus cell in an agent-based simulation framework under realistic cell flexibility values. We observed that flexible model cells can form aligned cell clusters when reversals are suppressed but these clusters disappeared when reversals frequency becomes similar to the observed value. However, M. xanthus cells follow slime (polysaccharide gel like material) trails left by other cells and we show that implementing this into our model rescues cell clustering for reversing cells. Our results show that slime following along with periodic cell reversals act as positive feedback to reinforce existing slime trails and recruit more cells. Furthermore, we have observed that mechanical cell alignment combined with slime following is sufficient to explain the distinct clustering patterns of reversing and non-reversing cells as observed in recent experiments. This work is supported by NSF MCB 0845919 and 1411780.

  13. Cellular Pressure and Volume Regulation and Implications for Cell Mechanics

    OpenAIRE

    Jiang, Hongyuan; Sun, Sean X.

    2013-01-01

    In eukaryotic cells, small changes in cell volume can serve as important signals for cell proliferation, death, and migration. Volume and shape regulation also directly impacts the mechanics of cells and tissues. Here, we develop a mathematical model of cellular volume and pressure regulation, incorporating essential elements such as water permeation, mechanosensitive channels, active ion pumps, and active stresses in the cortex. The model can fully explain recent experimental data, and it pr...

  14. Pathological relationships involving iron and myelin may constitute a shared mechanism linking various rare and common brain diseases

    Science.gov (United States)

    Heidari, Moones; Gerami, Sam H.; Bassett, Brianna; Graham, Ross M.; Chua, Anita C.G.; Aryal, Ritambhara; House, Michael J.; Collingwood, Joanna F.; Bettencourt, Conceição; Houlden, Henry; Ryten, Mina; Olynyk, John K.; Trinder, Debbie; Johnstone, Daniel M.; Milward, Elizabeth A.

    2016-01-01

    ABSTRACT We previously demonstrated elevated brain iron levels in myelinated structures and associated cells in a hemochromatosis Hfe−/−xTfr2mut mouse model. This was accompanied by altered expression of a group of myelin-related genes, including a suite of genes causatively linked to the rare disease family ‘neurodegeneration with brain iron accumulation’ (NBIA). Expanded data mining and ontological analyses have now identified additional myelin-related transcriptome changes in response to brain iron loading. Concordance between the mouse transcriptome changes and human myelin-related gene expression networks in normal and NBIA basal ganglia testifies to potential clinical relevance. These analyses implicate, among others, genes linked to various rare central hypomyelinating leukodystrophies and peripheral neuropathies including Pelizaeus-Merzbacher-like disease and Charcot-Marie-Tooth disease as well as genes linked to other rare neurological diseases such as Niemann-Pick disease. The findings may help understand interrelationships of iron and myelin in more common conditions such as hemochromatosis, multiple sclerosis and various psychiatric disorders. PMID:27500074

  15. Mechanism for Collective Cell Alignment in Myxococcus xanthus Bacteria.

    Directory of Open Access Journals (Sweden)

    Rajesh Balagam

    2015-08-01

    Full Text Available Myxococcus xanthus cells self-organize into aligned groups, clusters, at various stages of their lifecycle. Formation of these clusters is crucial for the complex dynamic multi-cellular behavior of these bacteria. However, the mechanism underlying the cell alignment and clustering is not fully understood. Motivated by studies of clustering in self-propelled rods, we hypothesized that M. xanthus cells can align and form clusters through pure mechanical interactions among cells and between cells and substrate. We test this hypothesis using an agent-based simulation framework in which each agent is based on the biophysical model of an individual M. xanthus cell. We show that model agents, under realistic cell flexibility values, can align and form cell clusters but only when periodic reversals of cell directions are suppressed. However, by extending our model to introduce the observed ability of cells to deposit and follow slime trails, we show that effective trail-following leads to clusters in reversing cells. Furthermore, we conclude that mechanical cell alignment combined with slime-trail-following is sufficient to explain the distinct clustering behaviors observed for wild-type and non-reversing M. xanthus mutants in recent experiments. Our results are robust to variation in model parameters, match the experimentally observed trends and can be applied to understand surface motility patterns of other bacterial species.

  16. Clinico-pathological correlation of E-cadherin expression at the invasive tumor front of Indian oral squamous cell carcinomas: An immunohistochemical study

    Science.gov (United States)

    Mehendiratta, Monica; Solomon, Monica Charlotte; Boaz, Karen; Guddattu, Vasudeva; Mohindra, Aashima

    2014-01-01

    Background: Recent studies have indicated that although malignant cells at the invasive tumor front, bare morphological resemblance to the cells at central portion of the tumor, their molecular character differs significantly. E-cadherin is a cell-cell adhesion molecule that connects epithelial cells. This study attempts to correlate the E-cadherin expression at the invasive tumor front with tumor differentiation along with its clinico-pathological parameters. Materials and Methods: Immunohistochemical staining with E-cadherin was carried out on archival cases of primary oral squamous cell carcinomas (n = 30). The E-cadherin expression at the invasive tumor front was analyzed and was linked to clinico-pathological parameters including patient prognosis. Results: The downregulation of E-cadherin expression at the invasive tumor edge when compared with patient's prognosis yielded a significant correlation (P = 0.041) but its correlation with the degree of differentiation determined was not significant (P = 0.27). Also, its association with tumor size and lymph node status was negative. Conclusions: Loss of E-cadherin expression at the invasive tumor front is an important event in the progression of oral squamous cell carcinomas. Tumors with a loss of expression of E-cadherin are those which had a poor prognosis PMID:25328302

  17. Cytotoxinic Mechanism of Hydroxyapatite Nanoparticles on Human Hepatoma Cell Lines

    Institute of Scientific and Technical Information of China (English)

    CAO Xian-ying; QI Zhi-tao; DAI Hong-lian; YAN Yu-hua; LI Shi-pu

    2003-01-01

    Stable and single-dispersed HAP nanoparticles were synthesized with chemical method assisted by ultrasonic treatment.HAP nanoparticles were surveyed by AFM and Zataplus.The effect on the Bel-7402 human hepatoma cell lines treated with HAP nanoparticles was investigated by the MTT methods and observation of morphology,and the mechanism was studied in changes of cell cycle and ultrastructure.The result shows that inhibition of HAP nanoparticles on the Bel-7402 human hepatoma cell lines is obviously in vitro.HAP nanoparticles the entered cancer cytoplasm,and cell proliferation is stopped at G1 phase of cell cycle,thus,cancer cells die directly.

  18. Ki-67 as a prognostic marker in mantle cell lymphoma-consensus guidelines of the pathology panel of the European MCL Network

    DEFF Research Database (Denmark)

    Klapper, W.; Hoster, E.; Determann, O.;

    2009-01-01

    powerful prognostic biomarker. The pathology panel of the European MCL Network evaluated methods to assess the Ki-67 index including stringent counting, digital image analysis, and estimation by eyeballing. Counting of 2 x 500 lymphoma cells is the gold standard to assess the Ki-67 index since this value.......37 for two methods of digital image analysis, respectively). Counting a reduced number of lymphoma cells (2 x 100 cells) showed high interobserver agreement (CCC = 0.74). Pitfalls of the Ki-67 index are discussed and guidelines and recommendations for assessing the Ki-67 index in MCL are given Udgivelsesdato......Mantle cell lymphoma (MCL) has a heterogeneous clinical course and is mainly an aggressive B cell non-Hodgkin lymphoma; however, there are some indolent cases The Ki-67 index, defined by the percentage of Ki-67-positive lymphoma cells on histopathological slides, has been shown to be a very...

  19. Pathologic and Protective Roles for Microglial Subsets and Bone Marrow- and Blood-Derived Myeloid Cells in Central Nervous System Inflammation

    DEFF Research Database (Denmark)

    Wlodarczyk, Agnieszka; Cédile, Oriane; Jensen, Kirstine Nolling;

    2015-01-01

    and also immunoregulation and regenerative processes. Better understanding and characterization of myeloid cell heterogeneity is essential for future development of treatments controlling inflammation and inducing neuroprotection and neuroregeneration in diseased CNS. Here, we describe and compare three......Inflammation is a series of processes designed for eventual clearance of pathogens and repair of damaged tissue. In the context of autoimmune recognition, inflammatory processes are usually considered to be pathological. This is also true for inflammatory responses in the central nervous system...

  20. Dynamic monitoring of cell mechanical properties using profile microindentation

    Science.gov (United States)

    Guillou, L.; Babataheri, A.; Puech, P.-H.; Barakat, A. I.; Husson, J.

    2016-02-01

    We have developed a simple and relatively inexpensive system to visualize adherent cells in profile while measuring their mechanical properties using microindentation. The setup allows simultaneous control of cell microenvironment by introducing a micropipette for the delivery of soluble factors or other cell types. We validate this technique against atomic force microscopy measurements and, as a proof of concept, measure the viscoelastic properties of vascular endothelial cells in terms of an apparent stiffness and a dimensionless parameter that describes stress relaxation. Furthermore, we use this technique to monitor the time evolution of these mechanical properties as the cells’ actin is depolymerized using cytochalasin-D.

  1. Mechanopathology of red blood cell diseases—Why mechanics matters

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    During the onset of a disease a cell may experience alterations in both the composition and organization of its cellular and molecular structures.These alterations may eventually lead to changes in its geometrical and mechanical properties such as cell size and shape,deformability and adhesion.As such,knowing how diseased cells respond to mechanical forces can reveal ways by which they differ from healthy ones.Here,we will present biomechanistic insights into red blood cell related diseases that manifest...

  2. The relationship between Interleukin 18 expression in laryngeal squamous cell carcinoma and clinical pathology as well as the effect of cetuximab on its expression

    Institute of Scientific and Technical Information of China (English)

    Xiu-Ping Liao; Nian Lyu; Sen-Lan Long

    2015-01-01

    Objective:To explore the relationship between Interleukin 18 (IL-18) expression in laryngeal squamous cell carcinoma and clinical pathology as well as the effect of cetuximab on its expression.Methods:40 cases of patients with laryngeal squamous cell carcinoma from January 2010 to June 2014 were chosen as the research group; 40 cases of patients with vocal cord polyp and 40 healthy volunteers were chosen as the control group. Statistical analysis was carried out on clinical pathology of laryngeal squamous cell carcinoma. IL-18, IFN-γ, TNF-αand IL-6 levels in peripheral blood mononuclear cells before and after cetuximab application were detected.Results:Detected IL-18 values of laryngeal squamous cell carcinoma group were higher than those of adjacent cancer tissue and vocal cord polyps; IL-18 positive rate (75.0%) of laryngeal squamous cell carcinoma group was higher than that of adjacent cancer tissue (47.5%) and polyp tissue (37.5%); IL-18 expressions of laryngeal squamous cell carcinoma group were related to primary lesion staging, differentiation degree and lymph node metastasis; before cetuximab application, IL-18 levels were significantly higher than those of the control group, and after cetuximab application, IL-18 levels significantly decreased than before. Differences were statistically significant; after cetuximab application, IFN-γ, TNF-αand IL-6 levels in PBMCs supernatant of patients with laryngeal squamous cell carcinoma were significantly lower than before. Differences were statistically significant.Conclusion:IL-18 can be highly expressed in laryngeal squamous cell carcinoma; IL-18 expression is involved in the occurrence and progress of laryngeal squamous cell carcinoma; IL-18 is possible to be involved in the occurrence and progress of laryngeal squamous cell carcinoma through regulating expressions of IFN-γ, TNF-α and IL-6, etc; IL-18 can be used as a target of laryngeal squamous cell carcinoma treatment, and cetuximab can inhibit IL-18

  3. Pathological gambling.

    Science.gov (United States)

    Hollander, E; Buchalter, A J; DeCaria, C M

    2000-09-01

    With increasing access to gambling facilities through casinos, the Internet, and other venues, PG is a rapidly emerging mental health concern. This impulse-control disorder tends to be comorbid with a wide range of other disorders and is reportedly associated with a high rate of suicide. For most gamblers, gambling is a form of entertainment, but for many individuals, the activity leads to far-reaching disruption of family and work. The personal and societal financial ramifications are severe, and many individuals with PG end up in the criminal justice system. An understanding of the neurobiology of PG is beginning to surface. 5-HT is linked to behavioral initiation and disinhibition, which are important in the onset of the gambling cycle and the difficulty in ceasing the behavior. Norepinephrine is associated with the arousal and risk taking in patients with PG. Dopamine is linked to positive and negative reward, the addictive component of this disorder. Effective treatment strategies for pathological gamblers are emerging. Potentially useful pharmacologic agents include SRIs (clomipramine and fluvoxamine), mood stabilizers for pathological gamblers with comorbid bipolar disorders (lithium), and naltrexone. Cognitive-behavioral psychotherapies offer promising results in the treatment of patients with this disorder. To devise prevention and early-intervention programs, research is needed to identify specific features of the individuals at risk for gambling problems. Education targeting vulnerable youth that show early signs of gambling behavior may be worthwhile and should be investigated further. Funding is necessary to support these endeavors, so perhaps a portion of tax revenues generated from the gambling industry should go toward specialized treatment facilities, educational efforts, and research into the neurobiology and treatment of PG. PMID:10986732

  4. Effects of estrogen on diverse stem cells and relevant intracellular mechanisms

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Sexual dimorphism definitely exists in the pathogenesis of a variety of cardiovascular,neurodegenerative and bone metabolism disorders.Estrogen affects the healing of ischemic myocardium partially through paracrine growth hormone production by bone marrow mesenchymal stem cells(MSCs) and facilitation on mobilization of endothelial progenitors cells(EPCs) to the ischemic myocardium.Estrogen can also inhibit the proliferation of the cardiac fibroblasts.Therefore,estrogen effectively enhances the neovascularization at the ischemic border zone and limits pathological myocardial remodeling.Moreover,estrogen increases proliferation of embryonic neural stem cells and accelerates differentiation of neurons during neurogenesis,suggesting a possible role of estrogen in transplantation of neural stem cells as a therapeutic approach for neurodegenerative diseases.Finally,estrogen can modulate osteogenic progenitors and osteoclasts,preventing the osteoporosis.In general,estrogen offers significant benefits on diverse stem/progenitor cell populations.A great understanding of estrogens on these cells and relevant intracellular mechanisms will allow modulation of the potent stem cells directly for the ultimate clinical applications.

  5. Mechanical downstream processing of Single Cell Oils

    OpenAIRE

    De Coninck, Maarten; Van Hecke, Renaat; Deprez, Koen; De Baerdemaeker, Josse

    2011-01-01

    During the last years, the third generation of bio fuels has been arousing more and more interest. Under certain conditions some micro organisms: yeasts, algae, fungi and bacteria, can accumulate up to 50% oil (based on dry weight). These so-called ‘Single cell oils’ (SCO) are well known in this context. Nowadays, harvesting and recovery of interesting products from microalgae is one of the most problematic areas of algal biofuel production technology. The traditional downstream process,...

  6. Bacterial cell curvature through mechanical control of cell growth

    DEFF Research Database (Denmark)

    Cabeen, M.; Charbon, Godefroid; Vollmer, W.;

    2009-01-01

    The cytoskeleton is a key regulator of cell morphogenesis. Crescentin, a bacterial intermediate filament-like protein, is required for the curved shape of Caulobacter crescentus and localizes to the inner cell curvature. Here, we show that crescentin forms a single filamentous structure...

  7. Exosomes in liver pathology.

    Science.gov (United States)

    Sato, Keisaku; Meng, Fanyin; Glaser, Shannon; Alpini, Gianfranco

    2016-07-01

    Exosomes are small (∼100nm) membrane-bound extracellular vesicles released by various types of cells into biological fluids. They contain proteins, mRNAs and miRNAs as cargo. Different cell types can take up exosomes by endocytosis and the cargo contained within them can be transferred horizontally to these recipient cells. Exosomal proteins and miRNAs can be functional and regulate physiological cell events modifying the microenvironment in target cells, a key event of liver pathology. Exosome-mediated cell-cell communication can alter tumor growth, cell migration, antiviral infection and hepatocyte regeneration, indicating that exosomes have great potential for development as diagnostic or therapeutic tools. Analyses of circulating total or exosomal miRNAs have identified a large number of candidate miRNAs that are regulated in liver diseases, and the diagnostic testing using single or multiple miRNAs shows good sensitivity and specificity. Some candidate miRNAs have been identified to play an important role in various liver disorders. This review summarizes recent findings on the role of extracellular vesicles in liver diseases and their diagnostic and therapeutic potential, mainly focusing on exosomes but also includes microvesicles in liver pathology. PMID:26988731

  8. A simple polymeric model describes cell nuclear mechanical response

    Science.gov (United States)

    Banigan, Edward; Stephens, Andrew; Marko, John

    The cell nucleus must continually resist inter- and intracellular mechanical forces, and proper mechanical response is essential to basic cell biological functions as diverse as migration, differentiation, and gene regulation. Experiments probing nuclear mechanics reveal that the nucleus stiffens under strain, leading to two characteristic regimes of force response. This behavior depends sensitively on the intermediate filament protein lamin A, which comprises the outer layer of the nucleus, and the properties of the chromatin interior. To understand these mechanics, we study a simulation model of a polymeric shell encapsulating a semiflexible polymer. This minimalistic model qualitatively captures the typical experimental nuclear force-extension relation and observed nuclear morphologies. Using a Flory-like theory, we explain the simulation results and mathematically estimate the force-extension relation. The model and experiments suggest that chromatin organization is a dominant contributor to nuclear mechanics, while the lamina protects cell nuclei from large deformations.

  9. The Signaling Mechanisms Underlying Cell Polarity and Chemotaxis

    OpenAIRE

    Wang, Fei

    2009-01-01

    Chemotaxis—the directed movement of cells in a gradient of chemoattractant—is essential for neutrophils to crawl to sites of inflammation and infection and for Dictyostelium discoideum (D. discoideum) to aggregate during morphogenesis. Chemoattractant-induced activation of spatially localized cellular signals causes cells to polarize and move toward the highest concentration of the chemoattractant. Extensive studies have been devoted to achieving a better understanding of the mechanism(s) use...

  10. Spectroscopic investigation of local mechanical impedance of living cells

    CERN Document Server

    Costa, Luca; Benseny-Cases, Núria; Mayeaux, Véronique; Chevrier, Joël; Comin, Fabio

    2013-01-01

    The mechanical properties of PC12 living cells have been studied at the nanoscale with a Force Feedback Microscope using two experimental approaches. Firstly, the local mechanical impedance of the cell membrane has been mapped simultaneously to the cell morphology at constant force. As the force of the interaction is gradually increased, we observed the appearance of the sub-membrane cytoskeleton. We shall compare the results obtained with this method with the measurement of other existing techniques. Secondly, a spectroscopic investigation has been performed varying the indentation of the tip in the cell membrane and consequently the force applied on it. In contrast with conventional dynamic atomic force microscopy techniques, here the small oscillation amplitude of the tip is not necessarily imposed at the cantilever first eigenmode. This allows the user to arbitrarily choose the excitation frequency in developing spectroscopic AFM techniques. The mechanical response of the PC12 cell membrane is found to be...

  11. Mechanisms of renin release from juxtaglomerular cells

    DEFF Research Database (Denmark)

    Skøtt, O; Salomonsson, Max; Sellerup Persson, Anja;

    1991-01-01

    In microdissected, nonperfused afferent arterioles changes in intravascular pressure did not affect renin secretion. On the contrary, renin release from isolated afferent arterioles perfused in a free-flow system has been reported to be sensitive to simultaneous changes in luminal pressure and flow....... Hence local blood flow may be involved in the baroreceptor control of renin release. If flow is sensed, the sensor is likely to be located near the endothelial cell layer, where ion channels have been shown to be influenced by variations in shear stress....

  12. Fibronectin matrix polymerization regulates smooth muscle cell phenotype through a Rac1 dependent mechanism.

    Directory of Open Access Journals (Sweden)

    Feng Shi

    Full Text Available Smooth muscle cells are maintained in a differentiated state in the vessel wall, but can be modulated to a synthetic phenotype following injury. Smooth muscle phenotypic modulation is thought to play an important role in the pathology of vascular occlusive diseases. Phenotypically modulated smooth muscle cells exhibit increased proliferative and migratory properties that accompany the downregulation of smooth muscle cell marker proteins. Extracellular matrix proteins, including fibronectin, can regulate the smooth muscle phenotype when used as adhesive substrates. However, cells produce and organize a 3-dimensional fibrillar extracellular matrix, which can affect cell behavior in distinct ways from the protomeric 2-dimensional matrix proteins that are used as adhesive substrates. We previously showed that the deposition/polymerization of fibronectin into the extracellular matrix can regulate the deposition and organization of other extracellular matrix molecules in vitro. Further, our published data show that the presence of a fibronectin polymerization inhibitor results in increased expression of smooth muscle cell differentiation proteins and inhibits vascular remodeling in vivo. In this manuscript, we used an in vitro cell culture system to determine the mechanism by which fibronectin polymerization affects smooth muscle phenotypic modulation. Our data show that fibronectin polymerization decreases the mRNA levels of multiple smooth muscle differentiation genes, and downregulates the levels of smooth muscle α-actin and calponin proteins by a Rac1-dependent mechanism. The expression of smooth muscle genes is transcriptionally regulated by fibronectin polymerization, as evidenced by the increased activity of luciferase reporter constructs in the presence of a fibronectin polymerization inhibitor. Fibronectin polymerization also promotes smooth muscle cell growth, and decreases the levels of actin stress fibers. These data define a Rac1

  13. Northwestern profiling of potential translation-regulatory proteins in human breast epithelial cells and malignant breast tissues: evidence for pathological activation of the IGF1R IRES.

    Science.gov (United States)

    Blume, Scott W; Jackson, Nateka L; Frost, Andra R; Grizzle, William E; Shcherbakov, Oleg D; Choi, Hyoungsoo; Meng, Zheng

    2010-06-01

    Genes involved in the control of cell proliferation and survival (those genes most important to cancer pathogenesis) are often specifically regulated at the translational level, through RNA-protein interactions involving the 5'-untranslated region of the mRNA. IGF1R is a proto-oncogene strongly implicated in human breast cancer, promoting survival and proliferation of tumor cells, as well as metastasis and chemoresistance. Our lab has focused on the molecular mechanisms regulating IGF1R expression at the translational level. We previously discovered an internal ribosome entry site (IRES) within the 5'-untranslated region of the human IGF1R mRNA, and identified and functionally characterized two individual RNA-binding proteins, HuR and hnRNP C, which bind the IGF1R 5'-UTR and differentially regulate IRES activity. Here we have developed and implemented a high-resolution northwestern profiling strategy to characterize, as a group, the full spectrum of sequence-specific RNA-binding proteins potentially regulating IGF1R translational efficiency through interaction with the 5'-untranslated sequence. The putative IGF1R IRES trans-activating factors (ITAFs) are a heterogeneous group of RNA-binding proteins including hnRNPs originating in the nucleus as well as factors tightly associated with ribosomes in the cytoplasm. The IGF1R ITAFs can be categorized into three distinct groups: (a) high molecular weight external ITAFs, which likely modulate the overall conformation of the 5'-untranslated region of the IGF1R mRNA and thereby the accessibility of the core functional IRES; (b) low molecular weight external ITAFs, which may function as general chaperones to unwind the RNA, and (c) internal ITAFs which may directly facilitate or inhibit the fundamental process of ribosome recruitment to the IRES. We observe dramatic changes in the northwestern profile of non-malignant breast cells downregulating IGF1R expression in association with acinar differentiation in 3-D culture

  14. Low to intermediate grade salivary duct carcinoma associated with osteoclast like-giant cell tumor of parotid gland: A rare case with distinct pathological features

    Directory of Open Access Journals (Sweden)

    Sunil Pasricha

    2013-01-01

    Full Text Available Osteoclast like-giant cell tumor of the salivary gland is an extremely rare tumor with distinct pathological features and unknown histogenesis. The neoplastic nature of these tumors in itself is questionable. We present the twentieth case in English literature of primary osteoclast like-giant cell tumor with accompanying low to intermediate grade salivary duct carcinoma of parotid gland, metastasizing to the ipsilateral cervical lymph node. As far as we know this is the second case with lymph node metastasis. Due to the rarity of the tumor its exact biological course is uncertain. We present and discuss this rare case with special emphasis on the histology, immunohistochemistry, and histogenesis.

  15. Investigation of temperature effect on cell mechanics by optofluidic microchips.

    Science.gov (United States)

    Yang, Tie; Nava, Giovanni; Minzioni, Paolo; Veglione, Manuela; Bragheri, Francesca; Lelii, Francesca Demetra; Vazquez, Rebeca Martinez; Osellame, Roberto; Cristiani, Ilaria

    2015-08-01

    Here we present the results of a study concerning the effect of temperature on cell mechanical properties. Two different optofluidic microchips with external temperature control are used to investigate the temperature-induced changes of highly metastatic human melanoma cells (A375MC2) in the range of ~0 - 35 °C. By means of an integrated optical stretcher, we observe that cells' optical deformability is strongly enhanced by increasing cell and buffer-fluid temperature. This finding is supported by the results obtained from a second device, which probes the cells' ability to be squeezed through a constriction. Measured data demonstrate a marked dependence of cell mechanical properties on temperature, thus highlighting the importance of including a proper temperature-control system in the experimental apparatus.

  16. Stress relaxation microscopy (STREM): Imaging mechanical force decay in cells

    CERN Document Server

    Moreno-Flores, Susana; Vivanco, Maria dM; Toca-Herrera, Jose Luis

    2009-01-01

    We have developed a novel scanning probe-based methodology to study cell biomechanics. The time dependence of the force exerted by the cell surface on a scanning probe at constant local deformation has been used to extract local relaxational responses. The generalized Maxwell viscoelastic model that accounts for multi relaxations fully describes the mechanical behaviour of the cell surface that exhibits a bimodal relaxation. Within the range of tested forces (0.1-4 nN) a slow and a fast relaxation with characteristic times of 0.1 and 1s have been detected and assigned to rearrangements in the cell membrane and cytoskeleton cortex, respectively. Relaxation time mapping allows to simultaneously detect non-uniformities in membrane and cytoskeletal mechanical behaviour and can be used as both identifying and diagnosing tools for cell type and cell disease.

  17. Mechanism of regulation of stem cell differentiation by matrix stiffness.

    Science.gov (United States)

    Lv, Hongwei; Li, Lisha; Sun, Meiyu; Zhang, Yin; Chen, Li; Rong, Yue; Li, Yulin

    2015-05-27

    Stem cell behaviors are regulated by multiple microenvironmental cues. As an external signal, mechanical stiffness of the extracellular matrix is capable of governing stem cell fate determination, but how this biophysical cue is translated into intracellular signaling remains elusive. Here, we elucidate mechanisms by which stem cells respond to microenvironmental stiffness through the dynamics of the cytoskeletal network, leading to changes in gene expression via biophysical transduction signaling pathways in two-dimensional culture. Furthermore, a putative rapid shift from original mechanosensing to de novo cell-derived matrix sensing in more physiologically relevant three-dimensional culture is pointed out. A comprehensive understanding of stem cell responses to this stimulus is essential for designing biomaterials that mimic the physiological environment and advancing stem cell-based clinical applications for tissue engineering.

  18. α-Synuclein vaccination modulates regulatory T cell activation and microglia in the absence of brain pathology

    DEFF Research Database (Denmark)

    Christiansen, Josefine R; Olesen, Mads N; Otzen, Daniel E;

    2016-01-01

    BACKGROUND: Passive and active immunization with α-synuclein has been shown to be neuroprotective in animal models of Parkinson's disease. We have previously shown that vaccination with α-synuclein, long before α-synuclein-induced brain pathology, prevents striatal degeneration by inducing regula...

  19. Long-term follow-up of post hematopoietic stem cell transplantation for Hurler syndrome: Clinical, biochemical, and pathological improvements

    Directory of Open Access Journals (Sweden)

    Eriko Yasuda

    2015-03-01

    In conclusion, this long-term post-HSCT observation should shed light on a new aspect of therapeutic effect associated with skeletal pathology and GAG levels as a biomarker, indicating that HSCT is a primary choice at an early stage for not only CNS but also skeletal system in combination of appropriate surgical procedures.

  20. Microchimerism in Endocrine Pathology

    OpenAIRE

    Rust, Daniel W.; Bianchi, Diana W.

    2009-01-01

    Chimerism in an individual refers to the coexistence of cells arising from two distinct organisms. It can arise iatrogenically via transplant or blood transfusion, and physiologically via twin to twin transfer, or from trafficking between mother and fetus during pregnancy. Many of the diseases associated with microchimerism affect the endocrine system (e.g., autoimmune thyroid disease and diabetes mellitus type 1). Microchimerism is relevant to endocrine pathology because (a) it is associated...

  1. Immunomodulatory functions of mesenchymal stem cells and possible mechanisms.

    Science.gov (United States)

    Wang, Qing; Ding, Gang; Xu, Xin

    2016-09-01

    In addition to their well-studied self-renewal capabilities and multipotent differentiation properties, mesenchymal stem cells (MSCs) have been reported to possess profound immunomodulatory functions both in vitro and in vivo. More and more studies have shown that MSCs are capable of interacting closely with almost all subsets of immune cells, such as T cells, B cells, dendritic cells, natural killer cells, macrophages, and neutrophils etc. The immunomodulatory property of MSCs may shed light on the treatment of a variety of autoimmune and inflammation-related diseases. In this article, we will review the studies on the immunomodulatory and anti-inflammatory functions of MSCs and the mechanisms responsible for the interaction between immune cells and MSCs, which could improve the development of promising approaches for cell-mediated immune therapies. PMID:26932157

  2. T-cell regulatory mechanisms in specific immunotherapy.

    Science.gov (United States)

    Jutel, Marek; Akdis, Cezmi A

    2008-01-01

    Allergen-specific immunotherapy (SIT) is the only treatment which leads to a lifelong tolerance against previously disease-causing allergens due to restoration of normal immunity against allergens. The description of T-regulatory (Treg) cells being involved in prevention of sensitization to allergens has led to great interest whether they represent a major target for allergen-SIT and whether it would be possible to manipulate Treg cells to increase its efficacy. Activationinduced cell death, anergy and/or immune response modulation by Treg cells are essential mechanisms of peripheral T-cell tolerance. There is growing evidence that anergy, tolerance and active suppression are not entirely distinct, but rather represent linked mechanisms possibly involving the same cells and multiple suppressor mechanisms. Skewing of allergen-specific effector T cells to Treg cells appears as a crucial event in the control of healthy immune response to allergens and successful allergen-SIT. The Treg cell response is characterized by abolished allergen- induced specific T-cell proliferation and suppressed Thelper (Th)1- and Th2-type cytokine secretion. In addition, mediators of allergic inflammation that trigger cAMP-associated G-protein-coupled receptors, such as histamine receptor-2, may contribute to peripheral tolerance mechanisms. The increased levels of interleukin-10 and transforming growth factor-Beta that are produced by Treg cells potently suppress IgE production, while simultaneously increasing production of non-inflammatory isotypes IgG4 and IgA, respectively. In addition, Treg cells directly or indirectly suppress effector cells of allergic inflammation such as mast cells, basophils and eosinophils. In conclusion, peripheral tolerance to allergens is controlled by multiple active suppression mechanisms. It is associated with regulation of antibody isotypes and effector cells to the direction of a healthy immune response. By the application of the recent knowledge in Treg

  3. A Comprehensive Review of Optical Stretcher for Cell Mechanical Characterization at Single-Cell Level

    Directory of Open Access Journals (Sweden)

    Tie Yang

    2016-05-01

    Full Text Available This paper presents a comprehensive review of the development of the optical stretcher, a powerful optofluidic device for single cell mechanical study by using optical force induced cell stretching. The different techniques and the different materials for the fabrication of the optical stretcher are first summarized. A short description of the optical-stretching mechanism is then given, highlighting the optical force calculation and the cell optical deformability characterization. Subsequently, the implementations of the optical stretcher in various cell-mechanics studies are shown on different types of cells. Afterwards, two new advancements on optical stretcher applications are also introduced: the active cell sorting based on cell mechanical characterization and the temperature effect on cell stretching measurement from laser-induced heating. Two examples of new functionalities developed with the optical stretcher are also included. Finally, the current major limitation and the future development possibilities are discussed.

  4. Mechanism of heavy ion radiation-induced cancer cell death

    International Nuclear Information System (INIS)

    We previously reported that the carbon beam triggers apoptosis in radio-resistant cancer cell lines via extracellular signal-regulated kinase (ERK)- and mitochondrial Bcl-2 family protein-dependant mechanism. Here, we further examined the further apoptosis-inducing mechanism of carbon beam in two glioma cell lines (T98G, U251). ERK1/2 knockdown experiments revealed that ERK regulates this apoptosis-inducing machinery upstream of mitochondria. Furthermore, we also found that both T98G cell and U251 cell stably expressing dominant-negative ERK2 suppress cell death induced by carbon beam irradiation. We also found proapoptotic PUMA and antiapoptotic Bcl-2 dynamically chang their expression levels corresponding to ERK activation after CB irradiation in U251 cell, and knockdown of PUMA decreased CB-induced U251 cell death. These data suggest that kinase action of ERK is essential for CB-induced glioma cell death, and proapoptotic PUMA and antiapoptotic Bcl-2 might be downstream targets of ERK in CB-induced glioma cell death mechanism. (author)

  5. Mechanisms of Organelle Inheritance in Dividing Plant Cells

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Organelles form essential compartments of all eukaryotic cells. Mechanisms that ensure the unbiased inheritance of organelles during cell division are therefore necessary to maintain the viability of future cell generations. Although inheritance of organelles represents a fundamental component of the cell cycle, surprisingly little is known about the underlying mechanisms that facilitate unbiased organelle inheritance. Evidence from a select number of studies, however,indicates that ordered organelle inheritance strategies exist in dividing cells of higher plants. The basic requirement for unbiased organelle inheritance is the duplication of organelle volume and distribution of the resulting organelle populations in a manner that facilitates unbiased partitioning of the organelle population to each daughter cell. Often, partitioning strategies are specific to the organelle, being influenced by the functional requirements of the organelle and whether the cells are mitotically active or re-entering into the cell cycle. Organelle partitioning mechanisms frequently depend on interactions with either the actin or microtubule cytoskeleton. In this focused review, we attempt to summarize key findings regarding organelle partitioning strategies in dividing cells of higher plants. We particularly concentrate on the role of the cytoskeleton in mediating unbiased organelle partitioning.

  6. Preclinical models for in vitro mechanical loading of bone-derived cells.

    Science.gov (United States)

    Michael Delaine-Smith, Robin; Javaheri, Behzad; Helen Edwards, Jennifer; Vazquez, Marisol; Rumney, Robin Mark Howard

    2015-01-01

    It is well established that bone responds to mechanical stimuli whereby physical forces are translated into chemical signals between cells, via mechanotransduction. It is difficult however to study the precise cellular and molecular responses using in vivo systems. In vitro loading models, which aim to replicate forces found within the bone microenvironment, make the underlying processes of mechanotransduction accessible to the researcher. Direct measurements in vivo and predictive modeling have been used to define these forces in normal physiological and pathological states. The types of mechanical stimuli present in the bone include vibration, fluid shear, substrate deformation and compressive loading, which can all be applied in vitro to monolayer and three-dimensional (3D) cultures. In monolayer, vibration can be readily applied to cultures via a low-magnitude, high-frequency loading rig. Fluid shear can be applied to cultures in multiwell plates via a simple rocking platform to engender gravitational fluid movement or via a pump to cells attached to a slide within a parallel-plate flow chamber, which may be micropatterned for use with osteocytes. Substrate strain can be applied via the vacuum-driven FlexCell system or via a four-point loading jig. 3D cultures better replicate the bone microenvironment and can also be subjected to the same forms of mechanical stimuli as monolayer, including vibration, fluid shear via perfusion flow, strain or compression. 3D cocultures that more closely replicate the bone microenvironment can be used to study the collective response of several cell types to loading. This technical review summarizes the methods for applying mechanical stimuli to bone cells in vitro. PMID:26331007

  7. Next-Generation Pathology.

    Science.gov (United States)

    Caie, Peter D; Harrison, David J

    2016-01-01

    The field of pathology is rapidly transforming from a semiquantitative and empirical science toward a big data discipline. Large data sets from across multiple omics fields may now be extracted from a patient's tissue sample. Tissue is, however, complex, heterogeneous, and prone to artifact. A reductionist view of tissue and disease progression, which does not take this complexity into account, may lead to single biomarkers failing in clinical trials. The integration of standardized multi-omics big data and the retention of valuable information on spatial heterogeneity are imperative to model complex disease mechanisms. Mathematical modeling through systems pathology approaches is the ideal medium to distill the significant information from these large, multi-parametric, and hierarchical data sets. Systems pathology may also predict the dynamical response of disease progression or response to therapy regimens from a static tissue sample. Next-generation pathology will incorporate big data with systems medicine in order to personalize clinical practice for both prognostic and predictive patient care.

  8. Mechanisms of radiation-induced neoplastic cell transformation

    Energy Technology Data Exchange (ETDEWEB)

    Yang, T.C.H.; Tobias, C.A.

    1984-04-01

    Studies with cultured mammalian cells demonstrated clearly that radiation can transform cells directly and can enhance the cell transformation by oncogenic DNA viruses. In general, high-LET heavy-ion radiation can be more effective than X and gamma rays in inducing neoplastic cell transformation. Various experimental results indicate that radiation-induced DNA damage, most likely double-strand breaks, is important for both the initiation of cell transformation and for the enhancement of viral transformation. Some of the transformation and enhancement lesions can be repaired properly in the cell, and the amount of irrepairable lesions produced by a given dose depends on the quality of radiation. An inhibition of repair processes with chemical agents can increase the transformation frequency of cells exposed to radiation and/or oncogenic viruses, suggesting that repair mechanisms may play an important role in the radiation transformation. The progression of radiation-transformed cells appears to be a long and complicated process that can be modulated by some nonmutagenic chemical agents, e.g., DMSO. Normal cells can inhibit the expression of transforming properties of tumorigenic cells through an as yet unknown mechanism. The progression and expression of transformation may involve some epigenetic changes in the irradiated cells. 38 references, 15 figures, 1 table.

  9. Mechanosensitive subcellular rheostasis drives emergent single-cell mechanical homeostasis

    Science.gov (United States)

    Weng, Shinuo; Shao, Yue; Chen, Weiqiang; Fu, Jianping

    2016-09-01

    Mechanical homeostasis--a fundamental process by which cells maintain stable states under environmental perturbations--is regulated by two subcellular mechanotransducers: cytoskeleton tension and integrin-mediated focal adhesions (FAs). Here, we show that single-cell mechanical homeostasis is collectively driven by the distinct, graduated dynamics (rheostasis) of subcellular cytoskeleton tension and FAs. Such rheostasis involves a mechanosensitive pattern wherein ground states of cytoskeleton tension and FA determine their distinct reactive paths through either relaxation or reinforcement. Pharmacological perturbations of the cytoskeleton and molecularly modulated integrin catch-slip bonds biased the rheostasis and induced non-homeostasis of FAs, but not of cytoskeleton tension, suggesting a unique sensitivity of FAs in regulating homeostasis. Theoretical modelling revealed myosin-mediated cytoskeleton contractility and catch-slip-bond-like behaviours in FAs and the cytoskeleton as sufficient and necessary mechanisms for quantitatively recapitulating mechanosensitive rheostasis. Our findings highlight the previously underappreciated physical nature of the mechanical homeostasis of cells.

  10. Measurement of red blood cell mechanics during morphological changes

    Science.gov (United States)

    Popescu, Gabriel; Park, Yongkeun; Best, Catherine; Dasari, Ramachandra; Feld, Michael; Kuriabova, Tatiana; Henle, Mark; Levine, Alex

    2010-03-01

    The human red blood cell (RBC) membrane, a fluid lipid bilayer tethered to an elastic 2D spectrin network, provides the principal control of the cell's morphology and mechanics. These properties, in turn, influence the ability of RBCs to transport oxygen in circulation. Current mechanical measurements of RBCs rely on external loads. Here we apply a Noncontact optical interferometric technique to quantify the thermal fluctuations of RBC membranes with 3 nm accuracy over a broad range of spatial and temporal frequencies. Combining this technique with a new mathematical model describing RBC membrane undulations, we measure the mechanical changes of RBCs as they undergo a transition from the normal discoid shape to the abnormal echinocyte and spherical shapes. These measurements indicate that, coincident with this morphological transition, there is a significant increase in the membrane's shear and bending moduli. This mechanical transition can alter cell circulation and impede oxygen delivery.

  11. Diverse Physiological Roles of Calcitonin Gene-Related Peptide in Migraine Pathology: Modulation of Neuronal-Glial-Immune Cells to Promote Peripheral and Central Sensitization.

    Science.gov (United States)

    Durham, Paul L

    2016-08-01

    The neuropeptide calcitonin gene-related peptide (CGRP) is implicated in the underlying pathology of migraine by promoting the development of a sensitized state of primary and secondary nociceptive neurons. The ability of CGRP to initiate and maintain peripheral and central sensitization is mediated by modulation of neuronal, glial, and immune cells in the trigeminal nociceptive signaling pathway. There is accumulating evidence to support a key role of CGRP in promoting cross excitation within the trigeminal ganglion that may help to explain the high co-morbidity of migraine with rhinosinusitis and temporomandibular joint disorder. In addition, there is emerging evidence that CGRP facilitates and sustains a hyperresponsive neuronal state in migraineurs mediated by reported risk factors such as stress and anxiety. In this review, the significant role of CGRP as a modulator of the trigeminal system will be discussed to provide a better understanding of the underlying pathology associated with the migraine phenotype. PMID:27334137

  12. Investigation of the Biochemical Mechanism for Cell-Substrate Mechanical Sensing

    Science.gov (United States)

    Ricotta, Vincent Anthony

    Advancements in stem cell biology and materials science have enabled the development of new treatments for tissue repair. Dental pulp stem cells (DPSCs), which are highly proliferative and can be induced to differentiate along several mesenchymal cell lineages, offer the possibility for pulpal regeneration and treatment of injured dentition. Polybutadiene (PB) may be used as a substrate for these cells. This elastomer can be spun casted into films of different thicknesses with different moduli. DPSCs grown on PB films, which are relatively hard (less than 1500 A thick), biomineralize depositing crystalline calcium phosphate without a requirement for the typical induction factor, dexamethasone (Dex). The moduli of cells track with the moduli of the surface suggesting that mechanics controls mineralization. The purpose of this study was to determine whether the major effect of Dex on biomineralization is the result of its ability to alter cell mechanics or its ability to induce osteogenesis/odontogenesis. DPSCs sense substrate mechanics through the focal adhesions, whose function is in part regulated by the Ras homolog gene (Rho) and its downstream effectors Rho associated kinases (ROCKs). ROCKs control actin filament polymerization and interactions with myosin light chain. Because cells sense substrate mechanics through focal adhesion proteins whose function is regulated by ROCKs, the impact of a ROCK inhibitor, Y-27632, was monitored. Blocking this pathway with Y-27632 suppressed the ability of DPSCs to sense the PB substrate. The cell modulus, plasma membrane stiffness, and cytosol stiffness were all lowered and biomineralization was suppressed in all cultures independent of substrate modulus or the presence of Dex. In other words, the inability of DPSCs to sense mechanical cues suppressed their ability to promote mineralization. On the other hand the expression of osteogenic/odontogenic markers (alkaline phosphatase and osteocalcin) was enhanced, perhaps due to Y

  13. Expression patterns of DLK1 and INSL3 identify stages of Leydig cell differentiation during normal development and in testicular pathologies, including testicular cancer and Klinefelter syndrome

    DEFF Research Database (Denmark)

    Lottrup, G; Nielsen, J E; Maroun, L L;

    2014-01-01

    STUDY QUESTION: What is the differentiation stage of human testicular interstitial cells, in particular Leydig cells (LC), within micronodules found in patients with infertility, testicular cancer and Klinefelter syndrome? SUMMARY ANSWER: The Leydig- and peritubular-cell populations in testes with......, are impaired in adult men with testicular pathologies including testis cancer and Klinefelter syndrome. STUDY FUNDING/COMPETING INTERESTS: This work was funded by Rigshospitalet's research funds, the Danish Cancer Society and Kirsten and Freddy Johansen's foundation. The authors have no conflicts of...... specimens and in 58 adult testis samples from patients with testicular germ cell tumours, including precursor carcinoma in situ (CIS), infertility or Klinefelter syndrome. PARTICIPANTS/MATERIALS, SETTING, METHODS: The expression patterns of DLK1, INSL3, chicken ovalbumin upstream promoter transcription...

  14. Human embryonic stem cell-derived pancreatic endoderm alleviates diabetic pathology and improves reproductive outcome in C57BL/KsJ-Lep(db/+) gestational diabetes mellitus mice.

    Science.gov (United States)

    Xing, Baoheng; Wang, Lili; Li, Qin; Cao, Yalei; Dong, Xiujuan; Liang, Jun; Wu, Xiaohua

    2015-07-01

    Gestational diabetes mellitus is a condition commonly encountered during mid to late pregnancy with pathologic manifestations including hyperglycemia, hyperinsulinemia, insulin resistance, and fetal maldevelopment. The cause of gestational diabetes mellitus can be attributed to both genetic and environmental factors, hence complicating its diagnosis and treatment. Pancreatic progenitors derived from human embryonic stem cells were shown to be able to effectively treat diabetes in mice. In this study, we have developed a system of treating diabetes using human embryonic stem cell-derived pancreatic endoderm in a mouse model of gestational diabetes mellitus. Human embryonic stem cells were differentiated in vitro into pancreatic endoderm, which were then transplanted into db/+ mice suffering from gestational diabetes mellitus. The transplant greatly improved glucose metabolism and reproductive outcome of the females compared with the control groups. Our findings support the feasibility of using differentiated human embryonic stem cells for treating gestational diabetes mellitus patients.

  15. Clinical and experimental pathology of Moyamoya disease

    Institute of Scientific and Technical Information of China (English)

    饶明俐; 张海鸥; 刘群; 张淑琴; 胡林森; 邓方

    2003-01-01

    Objective To investigate the etiology, pathology, and mechanism of pathogenesis of Moyamoya disease.Methods A total of 15 human autopsies were analyzed. In addition, in order to create an animal model of the disease, 21 Japanese rabbits were divided randomly into two groups and subjected to injections of horse serum either intravenously or locally in the area of the sympathetic ganglia. Pathological and immunohistochemical characteristics were observed.Results The pathological features of the autopsies and the animal models both involved intima hyperplasia and stenosis or even occlusion of the lumen in the terminal ends of the internal carotid artery and the anterior and middle cerebral arteries. Disconnections or even breakages of the inner layer of the lumen were also observed, without an obvious inflammatory response. Hyperplasic smooth muscle cells of the medial membrane had extended inward through broken portions of the internal elastic lamina, with intima cell hyperplasia resulting in lumen stenosis. The hyperplastic vascular walls were positive for IgG and IgM.Conclusions The etiology of Moyamoya disease may involve allergic angiitis. A possible mechanism is that proximal portions of the circle of Willis first develop chronic stenosis or occlusion, leading to compensatory small vessel proliferation, which perforates into the cerebral parenchyma.

  16. Mechanism of Suppression on Proliferation of QGY Cell by Oxaliplatin

    Institute of Scientific and Technical Information of China (English)

    HE Song; ZUO Guo-qing; ZHANG Yan; TANG Wei-xue; LIU Chang-an

    2007-01-01

    Objective: To observe the effects of oxaliplatin(L-OHP) on proliferation of human hepatoma cell line QGY in vitro and to investigate the mechanism. Methods: The inhibition of proliferation in QGY cell was assayed by MTT-test. Morphologic changes were observed under light microscope and electronic microscope. Distribution of cell cycle and apoptosis were analyzed using flow cytometry. The expressions of cell cycle proteins and apoptosis-associated proteins were detected with immuno-histochemical technique. Results: Oxaliplatin could inhibit the proliferation of QGY cells and the inhibition depended on the exposure time and dose. The cells showed morphologic changes of the early stage of apoptosis under the light microscope: the shrunk round cells, condensed cytoplasma and pycnosis of nucleus. Apoptotic cells and apoptotic body could be found under the transmission electronic microscope. The analysis of cell cycle indicated that oxaliplatin blocked cells at S and G2/M phases and the cells of G0/Gl phase reduced. When treated with oxaliplatin for 72h, the expressions of cyclin A and Bax were up-regulated, mutant type P53, Bcl-2 and Myc were down-regulated, and Fas was not changed. Conclusion: Oxaliplatin could inhibit the proliferation of the hepatoma cell lines. Cells were blocked at S and G2/M phases. The apoptosis was related to the up-regulation of Bax and down-regulation of mutant type P53, Bcl-2 and Myc. Oxaliplatin could not induce apoptosis through the Fas pathway.

  17. Stability and degradation mechanisms in organic solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Ecker, Bernhard

    2012-04-26

    This thesis deals with stability improvements and the investigation of degradation mechanisms in organic solar cells. Organic solar cells have been in the focus of extensive academic research for over almost two decades and are currently entering the market in small scale applications. For successful large scale applications, next to the improvement of the power conversion efficiency, the stability of organic solar cells has to be increased. This thesis is dedicated to the investigation of novel materials and architectures to study stability-related issues and degradation mechanisms in order to contribute to the basic understanding of the working principles of organic solar cells. Here, impedance spectroscopy, a frequency domain technique, is used to gain information about stability and degradation mechanisms in organic solar cells. In combination with systematic variations in the preparation of solar cells, impedance spectroscopy gives the possibility to differentiate between interface and bulk dominated effects. Additionally, impedance spectroscopy gives access to the dielectric properties of the device, such as capacitance. This offers among other things the opportunity to probe the charge carrier concentration and the density of states. Another powerful way of evaluation is the combination of experimentally obtained impedance spectra with equivalent circuit modelling. The thesis presents results on novel materials and solar cell architectures for efficient hole and electron extraction. This indicates the importance of knowledge over interlayers and interfaces for improving both the efficiency and stability of organic solar cells.

  18. The Mechanisms of Plant Cell Wall Deconstruction during Enzymatic Hydrolysis

    DEFF Research Database (Denmark)

    Thygesen, Lisbeth Garbrecht; E. Thybring, Emil; Johansen, Katja Salomon;

    2014-01-01

    Mechanical agitation during enzymatic hydrolysis of insoluble plant biomass at high dry matter contents is indispensable for the initial liquefaction step in biorefining. It is known that particle size reduction is an important part of liquefaction, but the mechanisms involved are poorly understood....... Here we put forward a simple model based on mechanical principles capable of capturing the result of the interaction between mechanical forces and cell wall weakening via hydrolysis of glucosidic bonds. This study illustrates that basic material science insights are relevant also within biochemistry...

  19. Mechanisms of pancreatic beta-cell growth and regeneration

    DEFF Research Database (Denmark)

    Nielsen, Jens Høiriis

    1989-01-01

    Information about the mechanism of beta-cell growth and regeneration may be obtained by studies of insulinoma cells. In the present study the growth and function of the rat insulinoma cell lines RINm5F and 5AH were evaluated by addition of serum, hormones, and growth factors. It was found...... that transferrin is the only obligatory factor whereas growth hormone, epidermal growth factor, fibroblast growth factor, and TRH had modulating effects. A heat-labile heparin binding serum factor which stimulated thymidine incorporation but not cell proliferation was demonstrated in human serum. Measurements...... of insulin mRNA content showed that the insulinoma cells only contained about 2% of that of normal rat beta-cells. These results are discussed in relation to the role of growth factors, oncogenes, and differentiation in the growth and regeneration of beta-cells....

  20. Bone marrow pathology in dogs and cats with non-regenerative immune-mediated haemolytic anaemia and pure red cell aplasia.

    Science.gov (United States)

    Weiss, D J

    2008-01-01

    Many dogs and cats with immune-mediated haemolytic anaemia (IMHA) lack a bone marrow erythroid regenerative response. To better understand the failure of the bone marrow to respond to the anaemia, bone marrow pathology associated with non-regenerative IMHA and pure red cell aplasia (PRCA) was reviewed. Eighty-two affected dogs and 57 affected cats were identified from a population presenting to a referral hospital over a 10-year period. Fifty-five dogs had non-regenerative IMHA (38 had bone marrow erythroid hyperplasia and 17 had erythroid maturation arrest) and 27 had pure red cell aplasia (PRCA). Twenty-eight cats had non-regenerative IMHA (24 had erythroid hyperplasia and 4 had erythroid maturation arrest) and 29 had PRCA. A variety of pathological changes were observed in bone marrow aspirates and core biopsy specimens taken from these animals. These changes included dysmyelopoiesis, myelonecrosis, myelofibrosis, interstitial oedema, haemorrhage, acute inflammation, haemophagocytic syndrome, lymphocyte aggregation, and lymphocyte or plasma cell hyperplasia. In both dogs and cats, dysmyelopoiesis, myelonecrosis, myelofibrosis, interstitial oedema, haemorrhage, acute inflammation and haemophagocytic syndrome were primarily noted in bone marrow specimens where there was evidence of erythroid hyperplasia. These animals were also more often neutropenic and thrombocytopenic, and had decreased 60 day survival when compared with dogs or cats with non-regenerative anaemia associated with erythroid maturation arrest or PRCA. Therefore, the pathogenesis of the non-regenerative anaemia in non-regenerative IMHA may involve both antibody-mediated destruction of bone marrow precursor cells and pathological events within the bone marrow that result in ineffective erythropoiesis.

  1. Parasite antigen-specific, IL-4-, TGFβ- and IL-1- dependent expansion of Th9 cells is associated with clinical pathology in human lymphatic filariasis

    Science.gov (United States)

    Anuradha, Rajamanickam; George, Parakkal Jovvian; Hanna, Luke E.; Chandrasekaran, Vedachalam; Kumaran, Paul; Nutman, Thomas B.; Babu, Subash

    2013-01-01

    Th9 cells are a subset of CD4+ T cells, shown to be important in allergy, autoimmunity and anti-tumor responses. However, their role in human infectious diseases has not been explored in detail. We identified a population of IL-9 and IL-10 co-expressing cells (lacking IL-4 expression) in normal individuals that respond to antigenic and mitogenic stimulation but are distinct from IL-9+ Th2 cells. We also demonstrate that these Th9 cells exhibit antigen –specific expansion in a chronic helminth infection (lymphatic filariasis). Comparison of Th9 responses reveals that individuals with pathology associated with filarial infection exhibit significantly expanded frequencies of filarial antigen induced Th9 cells but not of IL9+Th2 cells in comparison to filarial-infected individuals without associated disease. Moreover, the per cell production of IL-9 is significantly higher in Th9 cells compared to IL9+Th2 cells, indicating that the Th9 cells are the predominant CD4+ T cell subset producing IL-9 in the context of human infection. This expansion was reflected in elevated antigen stimulated IL-9 cytokine levels in whole blood culture supernatants. Finally, the frequencies of Th9 cells correlated positively with the severity of lymphedema (and presumed inflammation) in filarial diseased individuals. This expansion of Th9 cells was dependent on IL-4, TGFβ and IL-1 in vitro. We have therefore a identified an important human CD4+ T cell subpopulation co – expressing IL-9 and IL-10 but not IL-4 that is whose expansion is associated with disease in chronic lymphatic filariasis and could potentially play an important role in the pathogenesis of other inflammatory disorders. PMID:23913964

  2. Matrix metalloproteinase activity and glycosaminoglycans in chronic venous disease: the linkage among cell biology, pathology and translational research

    OpenAIRE

    Mannello, Ferdinando; Raffetto, Joseph D.

    2010-01-01

    Primary chronic venous disease (CVD) is an inflammatory pathology involving an erratic structural remodeling in the venous well leading to vascular incompetence and the development of varicose vein, characterized by altered collagen and elastin content. In the early steps of varicose vein formation is crucial the role of MMP/TIMP balance, implicated in both ECM and vascular degradation during inflammation processes in early and late stages of venous diseases. Although several pharmacological ...

  3. The epithelial cell adhesion molecule (Ep-CAM) as a morphoregulatory molecule is a tool in surgical pathology.

    NARCIS (Netherlands)

    Winter, M.J.; Nagtegaal, I.D.; Krieken, J.H.J.M. van; Litvinov, S.V.

    2003-01-01

    Cell adhesion receptors (CAMs) are actively involved in regulating various cell processes, including growth, differentiation, and cell death. Therefore, CAMs represent a large group of morphoregulating molecules, mediating cross-talk between cells and of cells with their environment. From this persp

  4. Mechanical memory and dosing influence stem cell fate

    Science.gov (United States)

    Yang, Chun; Tibbitt, Mark W.; Basta, Lena; Anseth, Kristi S.

    2014-06-01

    We investigated whether stem cells remember past physical signals and whether these can be exploited to dose cells mechanically. We found that the activation of the Yes-associated protein (YAP) and transcriptional coactivator with PDZ-binding domain (TAZ) as well as the pre-osteogenic transcription factor RUNX2 in human mesenchymal stem cells (hMSCs) cultured on soft poly(ethylene glycol) (PEG) hydrogels (Young’s modulus E ~ 2 kPa) depended on previous culture time on stiff tissue culture polystyrene (TCPS; E ~ 3 GPa). In addition, mechanical dosing of hMSCs cultured on initially stiff (E ~ 10 kPa) and then soft (E ~ 2 kPa) phototunable PEG hydrogels resulted in either reversible or—above a threshold mechanical dose—irreversible activation of YAP/TAZ and RUNX2. We also found that increased mechanical dosing on supraphysiologically stiff TCPS biases hMSCs towards osteogenic differentiation. We conclude that stem cells possess mechanical memory—with YAP/TAZ acting as an intracellular mechanical rheostat—that stores information from past physical environments and influences the cells’ fate.

  5. Cell death induced by mechanical compression on engineered muscle results from a gradual physiological mechanism.

    Science.gov (United States)

    Wu, Yabin; van der Schaft, Daisy W J; Baaijens, Frank P; Oomens, Cees W J

    2016-05-01

    Deep tissue injury (DTI), a type of pressure ulcer, arises in the muscle layers adjacent to bony prominences due to sustained mechanical loading. DTI presents a serious problem in the clinic, as it is often not visible until reaching an advanced stage. One of the causes can be direct mechanical deformation of the muscle tissue and cell. The mechanism of cell death induced by mechanical compression was studied using bio-artificial skeletal muscle tissues. Compression was applied by placing weights on top of the constructs. The morphological changes of the cytoskeleton and the phosphorylation of mitogen-activated protein kinases (MAPK) under compression were investigated. Moreover, inhibitors for each of the three major MAPK groups, p38, ERK, and JNK, were applied separately to look at their roles in the compression caused apoptosis and necrosis. The present study for the first time showed that direct mechanical compression activates MAPK phosphorylation. Compression also leads to a gradual destruction of the cytoskeleton. The percentage apoptosis is strongly reduced by p38 and JNK inhibitors down to the level of the unloaded group. This phenomenon could be observed up to 24h after initiation of compression. Therefore, cell death in bio-artificial muscle tissue caused by mechanical compression is primarily caused by a physiological mechanism, rather than through a physical mechanism which kills the cell directly. These findings reveal insight of muscle cell death under mechanical compression. Moreover, the result indicates a potential clinical solution to prevent DTI by pre-treating with p38 or/and JNK inhibitors. PMID:26961799

  6. Cell mechanics and immune system link up to fight infections

    Science.gov (United States)

    Ekpenyong, Andrew; Man, Si Ming; Tourlomousis, Panagiotis; Achouri, Sarra; Cammarota, Eugenia; Hughes, Katherine; Rizzo, Alessandro; Ng, Gilbert; Guck, Jochen; Bryant, Clare

    2015-03-01

    Infectious diseases, in which pathogens invade and colonize host cells, are responsible for one third of all mortality worldwide. Host cells use special proteins (immunoproteins) and other molecules to fight viral and bacterial invaders. The mechanisms by which immunoproteins enable cells to reduce bacterial loads and survive infections remain unclear. Moreover, during infections, some immunoproteins are known to alter the cytoskeleton, the structure that largely determines cellular mechanical properties. We therefore used an optical stretcher to measure the mechanical properties of primary immune cells (bone marrow derived macrophages) during bacterial infection. We found that macrophages become stiffer upon infection. Remarkably, macrophages lacking the immunoprotein, NLR-C4, lost the stiffening response to infection. This in vitro result correlates with our in vivo data whereby mice lacking NLR-C4 have more lesions and hence increased bacterial distribution and spread. Thus, the immune-protein-dependent increase in cell stiffness in response to bacterial infection (in vitro result) seems to have a functional role in the system level fight against pathogens (in vivo result). We will discuss how this functional link between cell mechanical properties and innate immunity, effected by actin polymerization, reduces the spread of infection.

  7. Laminin production by human endometrial stromal cells relates to the cyclic and pathologic state of the endometrium

    DEFF Research Database (Denmark)

    Faber, M; Wewer, U M; Berthelsen, J G;

    1986-01-01

    . However, commencing with the secretory phase, stromal cells accumulated distinct cytoplasmic and pericellular laminin-immunoreactive material. The maximal amount of stromal cell-associated laminin was observed in predecidual cells of the late secretory phase. Thus, laminin immunostaining discriminates...

  8. Mechanisms of mesenchymal stem/stromal cell function.

    Science.gov (United States)

    Spees, Jeffrey L; Lee, Ryang Hwa; Gregory, Carl A

    2016-01-01

    The past decade has seen an explosion of research directed toward better understanding of the mechanisms of mesenchymal stem/stromal cell (MSC) function during rescue and repair of injured organs and tissues. In addition to delineating cell-cell signaling and molecular controls for MSC differentiation, the field has made particular progress in defining several other mechanisms through which administered MSCs can promote tissue rescue/repair. These include: 1) paracrine activity that involves secretion of proteins/peptides and hormones; 2) transfer of mitochondria by way of tunneling nanotubes or microvesicles; and 3) transfer of exosomes or microvesicles containing RNA and other molecules. Improved understanding of MSC function holds great promise for the application of cell therapy and also for the development of powerful cell-derived therapeutics for regenerative medicine. Focusing on these three mechanisms, we discuss MSC-mediated effects on immune cell responses, cell survival, and fibrosis and review recent progress with MSC-based or MSC-derived therapeutics. PMID:27581859

  9. Membrane curvature in cell biology: An integration of molecular mechanisms.

    Science.gov (United States)

    Jarsch, Iris K; Daste, Frederic; Gallop, Jennifer L

    2016-08-15

    Curving biological membranes establishes the complex architecture of the cell and mediates membrane traffic to control flux through subcellular compartments. Common molecular mechanisms for bending membranes are evident in different cell biological contexts across eukaryotic phyla. These mechanisms can be intrinsic to the membrane bilayer (either the lipid or protein components) or can be brought about by extrinsic factors, including the cytoskeleton. Here, we review examples of membrane curvature generation in animals, fungi, and plants. We showcase the molecular mechanisms involved and how they collaborate and go on to highlight contexts of curvature that are exciting areas of future research. Lessons from how membranes are bent in yeast and mammals give hints as to the molecular mechanisms we expect to see used by plants and protists.

  10. Mechanism of T cell regulation by microRNAs

    International Nuclear Information System (INIS)

    MicroRNAs (miRNAs) are small, non-coding single-stranded RNAs that can modulate target gene expression at post-transcriptional level and participate in cell proliferation, differentiation, and apoptosis. T cells have important functions in acquired immune response; miRNAs regulate this immune response by targeting the mRNAs of genes involved in T cell development, proliferation, differentiation, and function. For instance, miR-181 family members function in progression by targeting Bcl2 and CD69, among others. MiR-17 to miR-92 clusters function by binding to CREB1, PTEN, and Bim. Considering that the suppression of T cell-mediated immune responses against tumor cells is involved in cancer progression, we should investigate the mechanism by which miRNA regulates T cells to develop new approaches for cancer treatment

  11. Mechanism of vaso-occlusion in sickle cell anemia

    Science.gov (United States)

    Lei, Huan; Karniadakis, George

    2012-11-01

    Vaso-occlusion crisis is one of the key hallmark of sickle cell anemia. While early studies suggested that the crisis is caused by blockage of a single elongated cell, recent experimental investigations indicate that vaso-occlusion is a complex process triggered by adhesive interactions among different cell groups in multiple stages. Based on dissipative particle dynamics, a multi-scale model for the sickle red blood cells (SS-RBCs), accounting for diversity in both shapes and cell rigidities, is developed to investigate the mechanism of vaso-occlusion crisis. Using this model, the adhesive dynamics of single SS-RBC was investigated in arterioles. Simulation results indicate that the different cell groups (deformable SS2 RBCs, rigid SS4 RBCs, leukocytes, etc.) exhibit heterogeneous adhesive behavior due to the different cell morphologies and membrane rigidities. We further simulate the tube flow of SS-RBC suspensions with different cell fractions. The more adhesive SS2 cells interact with the vascular endothelium and further trap rigid SS4 cells, resulting in vaso-occlusion in vessels less than 15 μm . Under inflammation, adherent leukocytes may also trap SS4 cells, resulting in vaso-occlusion in even larger vessels. This work was supported by the NSF grant CBET-0852948 and the NIH grant R01HL094270.

  12. Transdifferentiation of pancreatic α-cells into insulinsecreting cells: From experimental models to underlying mechanisms

    Institute of Scientific and Technical Information of China (English)

    Jieli; Lu; Rami; Jaafer; Rémy; Bonnavion; Philippe; Bertolino; Chang-Xian; Zhang

    2014-01-01

    Pancreatic insulin-secreting β-cells are essential regulators of glucose metabolism. New strategies are cur-rently being investigated to create insulin-producing β cells to replace deficient β cells, including the differentiation of either stem or progenitor cells, and the newly uncovered transdifferentiation of mature non-β islet cell types. However, in order to correctly drive any cell to adopt a new β-cell fate, a better understanding of the in vivo mechanisms involved in the plasticity and biology of islet cells is urgently required. Here, we review the recent studies reporting the phenomenon of transdifferentiation of α cells into β cells by focusing on the major candidates and contexts revealed to be involved in adult β-cell regeneration through this process. The possible underlying mechanisms of transdifferentiation and the interactions between several key factors involved in the process are also addressed. We propose that it is of importance to further study the molecular and cellular mechanisms underlying α- to β-cell transdifferentiation, in order to make β-cell regeneration from α cells a relevant and realizable strategy for developing cell-replacement therapy.

  13. Mechanisms underlying KCNQ1channel cell volume sensitivity

    DEFF Research Database (Denmark)

    Hammami, Sofia

    to the process of cell volume adjustments. A great diversity of potassium channels being members of either the 6TM, 4 TM or 2 TM K+ channel gene family have been shown to be strictly regulated by small, fast changes in cell volume. However, the precise mechanism underlying the K+ channel sensitivity to cell...... volume alterations is not yet fully understood. The KCNQ1 channel belonging to the voltage gated KCNQ family is considered a precise sensor of volume changes. The goal of this thesis was to elucidate the mechanism that induces cell volume sensitivity. Until now, a number of investigators have implicitly...... current. It is debated whether this increase in macroscopic current upon expression of KCNQ1 with KCNE1 is due to an increase in ion channel conductance (¿), the open state probability (Po) or an increase in the number of channels in the plasma membrane (N). The latter was quantified by measuring...

  14. Cell volume homeostatic mechanisms: effectors and signalling pathways

    DEFF Research Database (Denmark)

    Hoffmann, E K; Pedersen, Stine Helene Falsig

    2011-01-01

    the historical context of studies of cell volume regulation, focusing on the lineage started by Krogh, Bodil Schmidt-Nielsen, Hans-Henrik Ussing, and their students. The early work was focused on understanding the functional behaviour, kinetics and thermodynamics of the volume-regulatory ion transport......Cell volume homeostasis and its fine-tuning to the specific physiological context at any given moment are processes fundamental to normal cell function. The understanding of cell volume regulation owes much to August Krogh, yet has advanced greatly over the last decades. In this review, we outline...... mechanisms. Later work addressed the mechanisms through which cellular signalling pathways regulate the volume regulatory effectors or flux pathways. These studies were facilitated by the molecular identification of most of the relevant channels and transporters, and more recently also by the increased...

  15. The molecular mechanism of embryonic stem cell pluripotency maintenance

    Institute of Scientific and Technical Information of China (English)

    WANG Qingzhong; LIU Yixun; HAN Chunsheng

    2005-01-01

    In vitro cultured embryonic stem (ES) cells are derived from the inner cell mass (ICM) of pre-implantation embryos, and are capable of giving rise to all cell and tissue types of the three germ layers upon being injected back into blastocysts. These cells are therefore said to possess pluripotency that can be maintained infinitely in culture under optimal conditions. Such pluripotency maintenance is believed to be due to the symmetrical cleavage of the cells in an undifferentiated state. The pluripotency of ES cells is the basis for their various practical and potential applications. ES cells can be used as donor cells to generate knockout or transgenic animals, as in vitro models of mammalian development, and as cell resources for cell therapy in regenerative medicine. The further success in these applications, particularly in the last two, is dependent on the establishment of a culture system with components in the medium clearly defined and the subsequent procedures for controlled differentiation of the cells into specific lineages. In turn, elucidating the molecular mechanism for pluripotency maintenance of ES cells is the prerequisite. This paper summarizes the recent progresses in this area, focusing mainly on the LIF/STAT3, BMPs/Smads, canonical Wnt, TGFβ/activin/nodal, PI3K and FGF signaling pathways and the genes such as oct4, nanog that are crucial in ES cell pluripotency maintenance. The regulatory systems of pluripotency maintenance in both mouse and human ES cells are also discussed. We believe that the cross-talkings between these signaling pathways, as well as the regulatory system underlying pluripotency maintenance will be the main focus in the area of ES cell researches in the future.

  16. Molecular mechanisms of TRAIL-induced apoptosis of cancer cells

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    @@Tumor Necrosis Factor-related Apoptosis-inducing Ligand (TRAIL) is a recently identified member of the tumor necrosis factor (TNF) family[1]. Numerous studies indicate that TRAIL can induce apoptosis of cancer cells but not of normal cells, pointing to the possibility of de-veloping TRAIL into a cancer drug[2-4]. This review will summary the molecular mechanisms of TRAIL-induced apoptosis and discuss the questions to be resolved in this field.

  17. Fuel starvation. Irreversible degradation mechanisms in PEM fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    Rangel, Carmen M.; Silva, R.A.; Travassos, M.A.; Paiva, T.I.; Fernandes, V.R. [LNEG, National Laboratory for Energy and Geology, Lisboa (Portugal). UPCH Fuel Cells and Hydrogen Unit

    2010-07-01

    PEM fuel cell operates under very aggressive conditions in both anode and cathode. Failure modes and mechanism in PEM fuel cells include those related to thermal, chemical or mechanical issues that may constrain stability, power and lifetime. In this work, the case of fuel starvation is examined. The anode potential may rise to levels compatible with the oxidization of water. If water is not available, oxidation of the carbon support will accelerate catalyst sintering. Diagnostics methods used for in-situ and ex-situ analysis of PEM fuel cells are selected in order to better categorize irreversible changes of the cell. Electrochemical Impedance Spectroscopy (EIS) is found instrumental in the identification of fuel cell flooding conditions and membrane dehydration associated to mass transport limitations / reactant starvation and protonic conductivity decrease, respectively. Furthermore, it indicates that water electrolysis might happen at the anode. Cross sections of the membrane catalyst and gas diffusion layers examined by scanning electron microscopy indicate electrode thickness reduction as a result of reactions taking place during hydrogen starvation. Catalyst particles are found to migrate outwards and located on carbon backings. Membrane degradation in fuel cell environment is analyzed in terms of the mechanism for fluoride release which is considered an early predictor of membrane degradation. (orig.)

  18. Genetic and Epigenetic Mechanisms That Maintain Hematopoietic Stem Cell Function

    Directory of Open Access Journals (Sweden)

    Christian Kosan

    2016-01-01

    Full Text Available All hematopoiesis cells develop from multipotent progenitor cells. Hematopoietic stem cells (HSC have the ability to develop into all blood lineages but also maintain their stemness. Different molecular mechanisms have been identified that are crucial for regulating quiescence and self-renewal to maintain the stem cell pool and for inducing proliferation and lineage differentiation. The stem cell niche provides the microenvironment to keep HSC in a quiescent state. Furthermore, several transcription factors and epigenetic modifiers are involved in this process. These create modifications that regulate the cell fate in a more or less reversible and dynamic way and contribute to HSC homeostasis. In addition, HSC respond in a unique way to DNA damage. These mechanisms also contribute to the regulation of HSC function and are essential to ensure viability after DNA damage. How HSC maintain their quiescent stage during the entire life is still matter of ongoing research. Here we will focus on the molecular mechanisms that regulate HSC function.

  19. Mechanical Response of Single Plant Cells to Cell Poking: A Numerical Simulation Model

    Institute of Scientific and Technical Information of China (English)

    Rong Wang; Qun-Ying Jiao; De-Qiang Wei

    2006-01-01

    Cell poking is an experimental technique that is widely used to study the mechanical properties of plant cells. A full understanding of the mechanical responses of plant cells to poking force is helpful for experimental work. The aim of this study was to numerically investigate the stress distribution of the cell wall,cell turgor, and deformation of plant cells in response to applied poking force. Furthermore, the locations damaged during poking were analyzed. The model simulates cell poking, with the cell treated as a spherical,homogeneous, isotropic elastic membrane, filled with incompressible, highly viscous liquid. Equilibrium equations for the contact region and the non-contact regions were determined by using membrane theory.The boundary conditions and continuity conditions for the solution of the problem were found. The forcedeformation curve, turgor pressure and tension of the cell wall under cell poking conditions were obtained.The tension of the cell wall circumference was larger than that of the meridian. In general, maximal stress occurred at the equator around. When cell deformation increased to a certain level, the tension at the poker tip exceeded that of the equator. Breakage of the cell wall may start from the equator or the poker tip,depending on the deformation. A nonlinear model is suitable for estimating turgor, stress, and stiffness,and numerical simulation is a powerful method for determining plant cell mechanical properties.

  20. 基底细胞癌的病理诊断分析及预后%Pathological Diagnosis and Prognostic of Basal Cell Carcinoma

    Institute of Scientific and Technical Information of China (English)

    杜晓敏

    2015-01-01

    目的:探讨基底细胞癌的病理诊断分析及预后。方法整群选取2010年10月—2014年5月在该病理科进行基底细胞癌的病理诊断的74例患者作为研究对象,并对其病理资料进行回顾性分析。结果74例基底细胞癌患者中,眶周部23例,占31.1%,峡部5例,占6.8%,额部9例,占12.2%,颧骨部7例,占9.4%,鼻翼部19例,占25.6%,上唇部6例,占8.1%,下颌部3例,占4.1%,背部2例,占2.7%。镜下可见瘤细胞团块状或巢状排列,细胞核大小不一,排列密集紊乱,胞浆少淡染,瘤细胞巢周围裂隙形成,间质慢性炎细胞浸润。结论基底细胞癌是皮肤科最常见的恶性肿瘤之一,及早进行病理诊断和治疗,预后较好,可以明显的提高患者的生命质量。%Objective To investigate the pathological diagnosis and the prognosis of basal cell carcinoma. Methods 74 patients who underwent pathological diagnosis of basal cell carcinoma in our hospital from October 2010 to May 2014 in the Department of Pathology of our hospital were selected as the research object and their pathological data were retrospectively analyzed. Results In all the 74 patients, basal cell carcinoma in periorbital region was found in 23 cases, accounting for 31.1%; in isthmus in 5 cases, accounting for 6.8%; in forehead in 9 cases, accounting for 12.2%, in the zygomatic in 7 cases, accounting for 9.4%, in alae nasi in 19 cases, accounting for 25.6%, in upper lip in 6 cases, accounting for 8.1%, in lower jaw in 3 cases, accounting for 4.1% and in back in 2 cases, accounted for 2.7%. Under the microscope, the tumor cells, of which the nucleus of difference size were ar-ranged dense and irregular, and of which the scanty cytoplasm was slightly stained, distributed in the form of round or spindle and of nest. Interstitial chronic inflammatory cell infiltration was developed in the fracture around tumor cells. Conclusion Basal cell carcinoma is one of

  1. NKG2D mediates NK cell hyperresponsiveness and influenza-induced pathologies in a mouse model of chronic obstructive pulmonary disease.

    Science.gov (United States)

    Wortham, Brian W; Eppert, Bryan L; Motz, Greg T; Flury, Jennifer L; Orozco-Levi, Mauricio; Hoebe, Kasper; Panos, Ralph J; Maxfield, Melissa; Glasser, Stephan W; Senft, Albert P; Raulet, David H; Borchers, Michael T

    2012-05-01

    Chronic obstructive pulmonary disease (COPD) is characterized by peribronchial and perivascular inflammation and largely irreversible airflow obstruction. Acute disease exacerbations, due frequently to viral infections, lead to enhanced disease symptoms and contribute to long-term progression of COPD pathology. Previously, we demonstrated that NK cells from cigarette smoke (CS)-exposed mice exhibit enhanced effector functions in response to stimulating cytokines or TLR ligands. In this article, we show that the activating receptor NKG2D is a key mediator for CS-stimulated NK cell hyperresponsiveness, because CS-exposed NKG2D-deficient mice (Klrk1(-/-)) did not exhibit enhanced effector functions as assessed by cytokine responsiveness. NK cell cytotoxicity against MHC class I-deficient targets was not affected in a COPD model. However, NK cells from CS-exposed mice exhibit greater cytotoxic activity toward cells that express the NKG2D ligand RAET1ε. We also demonstrate that NKG2D-deficient mice exhibit diminished airway damage and reduced inflammation in a model of viral COPD exacerbation, which do not affect viral clearance. Furthermore, adoptive transfer of NKG2D(+) NK cells into CS-exposed, influenza-infected NKG2D-deficient mice recapitulated the phenotypes observed in CS-exposed, influenza-infected wild-type mice. Our findings indicate that NKG2D stimulation during long-term CS exposure is a central pathway in the development of NK cell hyperresponsiveness and influenza-mediated exacerbations of COPD. PMID:22467655

  2. Bithionol inhibits ovarian cancer cell growth In Vitro - studies on mechanism(s) of action

    International Nuclear Information System (INIS)

    Drug resistance is a cause of ovarian cancer recurrence and low overall survival rates. There is a need for more effective treatment approaches because the development of new drug is expensive and time consuming. Alternatively, the concept of ‘drug repurposing’ is promising. We focused on Bithionol (BT), a clinically approved anti-parasitic drug as an anti-ovarian cancer drug. BT has previously been shown to inhibit solid tumor growth in several preclinical cancer models. A better understanding of the anti-tumor effects and mechanism(s) of action of BT in ovarian cancer cells is essential for further exploring its therapeutic potential against ovarian cancer. The cytotoxic effects of BT against a panel of ovarian cancer cell lines were determined by Presto Blue cell viability assay. Markers of apoptosis such as caspases 3/7, cPARP induction, nuclear condensation and mitochondrial transmembrane depolarization were assessed using microscopic, FACS and immunoblotting methods. Mechanism(s) of action of BT such as cell cycle arrest, reactive oxygen species (ROS) generation, autotaxin (ATX) inhibition and effects on MAPK and NF-kB signalling were determined by FACS analysis, immunoblotting and colorimetric methods. BT caused dose dependent cytotoxicity against all ovarian cancer cell lines tested with IC50 values ranging from 19 μM – 60 μM. Cisplatin-resistant variants of A2780 and IGROV-1 have shown almost similar IC50 values compared to their sensitive counterparts. Apoptotic cell death was shown by expression of caspases 3/7, cPARP, loss of mitochondrial potential, nuclear condensation, and up-regulation of p38 and reduced expression of pAkt, pNF-κB, pIκBα, XIAP, bcl-2 and bcl-xl. BT treatment resulted in cell cycle arrest at G1/M phase and increased ROS generation. Treatment with ascorbic acid resulted in partial restoration of cell viability. In addition, dose and time dependent inhibition of ATX was observed. BT exhibits cytotoxic effects on various

  3. Giant Glial Cell: New Insight Through Mechanism-Based Modeling

    DEFF Research Database (Denmark)

    Postnov, D. E.; Ryazanova, L. S.; Brazhe, Nadezda;

    2008-01-01

    The paper describes a detailed mechanism-based model of a tripartite synapse consisting of P- and R-neurons together with a giant glial cell in the ganglia of the medical leech (Hirudo medicinalis), which is a useful object for experimental studies in situ. We describe the two main pathways of th...

  4. Cell Mechanisms of Bone Tissue Loss Under Space Flight Conditions

    Science.gov (United States)

    Rodionova, Natalia

    Investigations on the space biosatellites has shown that the bone skeleton is one of the most im-portant targets of the effect space flight factors on the organism. Bone tissue cells were studied by electron microscopy in biosamples of rats' long bones flown on the board american station "SLS-2" and in experiments with modelling of microgravity ("tail suspension" method) with using autoradiography. The analysis of data permits to suppose that the processes of remod-eling in bone tissue at microgravity include the following succession of cell-to-cell interactions. Osteocytes as mechanosensory cells are first who respond to a changing "mechanical field". The next stage is intensification of osteolytic processes in osteocytes, leading to a volume en-largement of the osteocytic lacunae and removal of the "excess bone". Then mechanical signals have been transmitted through a system of canals and processes of the osteocytic syncitium to certain superficial bone zones and are perceived by osteoblasts and bone-lining cells (superficial osteocytes), as well as by the bone-marrow stromal cells. The sensitivity of stromal cells, pre-osteoblasts and osteoblasts, under microgravity was shown in a number of works. As a response to microgravity, the system of stromal cells -preosteoblasts -osteoblasts displays retardation of proliferation, differentiation and specific functions of osteogenetic cells. This is supported by the 3H-thymidine studies of the dynamics of differentiation of osteogenetic cells in remodeling zones. But unloading is not adequate and in part of the osteocytes are apoptotic changes as shown by our electron microscopic investigations. An osteocytic apoptosis can play the role in attraction the osteoclasts and in regulation of bone remodeling. The apoptotic bodies with a liquid flow through a system of canals are transferred to the bone surface, where they fulfil the role of haemoattractants for monocytes come here and form osteoclasts. The osteoclasts destroy

  5. Molecule mechanism of stem cells in Arabidopsis thaliana

    Directory of Open Access Journals (Sweden)

    Wenjin Zhang

    2014-01-01

    Full Text Available Plants possess the ability to continually produce new tissues and organs throughout their life. Unlike animals, plants are exposed to extreme variations in environmental conditions over the course of their lives. The vitality of plants is so powerful that they can survive several hundreds of years or even more making it an amazing miracle that comes from plant stem cells. The stem cells continue to divide to renew themselves and provide cells for the formation of leaves, stems, and flowers. Stem cells are not only quiescent but also immortal, pluripotent and homeostatic. Stem cells are the magic cells that repair tissues and regenerate organs. During the past decade, scholars around the world have paid more and more attention toward plant stem cells. At present, the major challenge is in relating molecule action mechanism to root apical meristem, shoot apical meristem and vascular system. The coordination between stem cells maintenance and differentiation is critical for normal plant growth and development. Elements such as phytohormones, transcription factors and some other known or unknown genes cooperate to balance this process. In this review, Arabidopsis thaliana as a pioneer system, we highlight recent developments in molecule modulating, illustrating how plant stem cells generate new mechanistic insights into the regulation of plants growth and development.

  6. Retinal Angiogenesis Effects of TGF-β1 and Paracrine Factors Secreted From Human Placental Stem Cells in Response to a Pathological Environment.

    Science.gov (United States)

    Kim, Kyung-Sul; Park, Ji-Min; Kong, TaeHo; Kim, Chul; Bae, Sang-Hun; Kim, Han Wool; Moon, Jisook

    2016-01-01

    Abnormal angiogenesis is a primary cause of many eye diseases, including diabetic retinopathy, age-related macular degeneration, and retinopathy of prematurity. Mesenchymal stem cells (MSCs) are currently being investigated as a treatment for several such retinal diseases based on their neuroprotective and angiogenic potentials. In this study, we evaluated the role of systemically injected human placental amniotic membrane-derived MSCs (AMSCs) on pathological neovascularization of proliferative retinopathy. We determined that AMSCs secrete higher levels of transforming growth factor-β (TGF-β1) than other MSCs, and the secreted TGF-β1 directly suppresses the proliferation of endothelial cells under pathological conditions in vitro. Moreover, in a mouse model of oxygen-induced retinopathy, intraperitoneally injected AMSCs migrated into the retina and suppressed excessive neovascularization of the vasculature via expression of TGF-β1, and the antineovascular effect of AMSCs was blocked by treatment with TGF-β1 siRNA. These findings are the first to demonstrate that TGF-β1 secreted from AMSCs is one of the key factors to suppress retinal neovascularization in proliferative retinopathy and further elucidate the therapeutic function of AMSCs for the treatment of retinal neovascular diseases.

  7. Mechanical properties of plant cell walls probed by relaxation spectra

    DEFF Research Database (Denmark)

    Hansen, Steen Laugesen; Ray, Peter Martin; Karlsson, Anders Ola;

    2011-01-01

    type. This may be due to the plant’s ability to compensate for the wall modification or because the biophysical method that is often employed, determination of simple elastic modulus and breakstrength, lacks the resolving power necessary for detecting subtle mechanical phenotypes. Here, we apply...... a method, determination of relaxation spectra, which probes, and can separate, the viscoelastic properties of different cell wall components (i.e. those properties that depend on the elastic behavior of load-bearing wall polymers combined with viscous interactions between them). A computer program, Bayes......Relax, that deduces relaxation spectra from appropriate rheological measurements is presented and made accessible through a Web interface. BayesRelax models the cell wall as a continuum of relaxing elements, and the ability of the method to resolve small differences in cell wall mechanical properties is demonstrated...

  8. Chemo-mechanical control of neural stem cell differentiation

    Science.gov (United States)

    Geishecker, Emily R.

    Cellular processes such as adhesion, proliferation, and differentiation are controlled in part by cell interactions with the microenvironment. Cells can sense and respond to a variety of stimuli, including soluble and insoluble factors (such as proteins and small molecules) and externally applied mechanical stresses. Mechanical properties of the environment, such as substrate stiffness, have also been suggested to play an important role in cell processes. The roles of both biochemical and mechanical signaling in fate modification of stem cells have been explored independently. However, very few studies have been performed to study well-controlled chemo-mechanotransduction. The objective of this work is to design, synthesize, and characterize a chemo-mechanical substrate to encourage neuronal differentiation of C17.2 neural stem cells. In Chapter 2, Polyacrylamide (PA) gels of varying stiffnesses are functionalized with differing amounts of whole collagen to investigate the role of protein concentration in combination with substrate stiffness. As expected, neurons on the softest substrate were more in number and neuronal morphology than those on stiffer substrates. Neurons appeared locally aligned with an expansive network of neurites. Additional experiments would allow for statistical analysis to determine if and how collagen density impacts C17.2 differentiation in combination with substrate stiffness. Due to difficulties associated with whole protein approaches, a similar platform was developed using mixed adhesive peptides, derived from fibronectin and laminin, and is presented in Chapter 3. The matrix elasticity and peptide concentration can be individually modulated to systematically probe the effects of chemo-mechanical signaling on differentiation of C17.2 cells. Polyacrylamide gel stiffness was confirmed using rheological techniques and found to support values published by Yeung et al. [1]. Cellular growth and differentiation were assessed by cell counts

  9. Interferon Regulator Factor 8 (IRF8 Limits Ocular Pathology during HSV-1 Infection by Restraining the Activation and Expansion of CD8+ T Cells.

    Directory of Open Access Journals (Sweden)

    Lin Sun

    Full Text Available Interferon Regulatory Factor-8 (IRF8 is constitutively expressed in monocytes and B cell lineages and plays important roles in immunity to pathogens and cancer. Although IRF8 expression is induced in activated T cells, the functional relevance of IRF8 in T cell-mediated immunity is not well understood. In this study, we used mice with targeted deletion of Irf8 in T-cells (IRF8KO to investigate the role of IRF8 in T cell-mediated responses during herpes simplex virus 1 (HSV-1 infection of the eye. In contrast to wild type mice, HSV-1-infected IRF8KO mice mounted a more robust anti-HSV-1 immune response, which included marked expansion of HSV-1-specific CD8+ T cells, increased infiltration of inflammatory cells into the cornea and trigeminal ganglia (TG and enhanced elimination of virus within the trigeminal ganglion. However, the consequence of the enhanced immunological response was the development of ocular inflammation, limbitis, and neutrophilic infiltration into the cornea of HSV-1-infected IRF8KO mice. Surprisingly, we observed a marked increase in virus-specific memory precursor effector cells (MPEC in IRF8KO mice, suggesting that IRF8 might play a role in regulating the differentiation of effector CD8+ T cells to the memory phenotype. Together, our data suggest that IRF8 might play a role in restraining excess lymphocyte proliferation. Thus, modulating IRF8 levels in T cells can be exploited therapeutically to prevent immune-mediated ocular pathology during autoimmune and infectious diseases of the eye.

  10. Interferon Regulator Factor 8 (IRF8) Limits Ocular Pathology during HSV-1 Infection by Restraining the Activation and Expansion of CD8+ T Cells

    Science.gov (United States)

    Yu, Cheng-Rong; He, Chang; Mahdi, Rashid M.; Chan, Chi-Chao; Wang, Hongsheng; Morse, Herbert C.; Egwuagu, Charles E.

    2016-01-01

    Interferon Regulatory Factor-8 (IRF8) is constitutively expressed in monocytes and B cell lineages and plays important roles in immunity to pathogens and cancer. Although IRF8 expression is induced in activated T cells, the functional relevance of IRF8 in T cell-mediated immunity is not well understood. In this study, we used mice with targeted deletion of Irf8 in T-cells (IRF8KO) to investigate the role of IRF8 in T cell-mediated responses during herpes simplex virus 1 (HSV-1) infection of the eye. In contrast to wild type mice, HSV-1-infected IRF8KO mice mounted a more robust anti-HSV-1 immune response, which included marked expansion of HSV-1-specific CD8+ T cells, increased infiltration of inflammatory cells into the cornea and trigeminal ganglia (TG) and enhanced elimination of virus within the trigeminal ganglion. However, the consequence of the enhanced immunological response was the development of ocular inflammation, limbitis, and neutrophilic infiltration into the cornea of HSV-1-infected IRF8KO mice. Surprisingly, we observed a marked increase in virus-specific memory precursor effector cells (MPEC) in IRF8KO mice, suggesting that IRF8 might play a role in regulating the differentiation of effector CD8+ T cells to the memory phenotype. Together, our data suggest that IRF8 might play a role in restraining excess lymphocyte proliferation. Thus, modulating IRF8 levels in T cells can be exploited therapeutically to prevent immune-mediated ocular pathology during autoimmune and infectious diseases of the eye. PMID:27171004

  11. Notch1-Dll4 signalling and mechanical force regulate leader cell formation during collective cell migration.

    Science.gov (United States)

    Riahi, Reza; Sun, Jian; Wang, Shue; Long, Min; Zhang, Donna D; Wong, Pak Kin

    2015-03-13

    At the onset of collective cell migration, a subset of cells within an initially homogenous population acquires a distinct 'leader' phenotype with characteristic morphology and motility. However, the factors driving the leader cell formation as well as the mechanisms regulating leader cell density during the migration process remain to be determined. Here we use single-cell gene expression analysis and computational modelling to show that the leader cell identity is dynamically regulated by Dll4 signalling through both Notch1 and cellular stress in a migrating epithelium. Time-lapse microscopy reveals that Dll4 is induced in leader cells after the creation of the cell-free region and leader cells are regulated via Notch1-Dll4 lateral inhibition. Furthermore, mechanical stress inhibits Dll4 expression and leader cell formation in the monolayer. Collectively, our findings suggest that a reduction of mechanical force near the boundary promotes Notch1-Dll4 signalling to dynamically regulate the density of leader cells during collective cell migration.

  12. Cell death mechanisms vary with photodynamic therapy dose and photosensitizer

    Science.gov (United States)

    He, Jin; Oleinick, Nancy L.

    1995-03-01

    Mouse lymphoma L5178Y-R cells respond to photodynamic therapy (PDT) by undergoing rapid apoptosis, which is induced by PDT-activated signal transduction initiating in the damaged cellular membranes. To relate the level of PDT damage and photosensitizer to the mechanism of cell death, apoptosis has been detected by agarose gel electrophoresis of fragmented DNA and quantified by flow cytometry of cells after staining with Hoechst33342 and propidium iodide, a technique which can distinguish between live, apoptotic, and necrotic cells. When the silicon phthalocyanine Pc 4 or Pc 12 served as photosensitizer, lethal doses (as defined by clonogenic assay) of PDT induced apoptosis in essentially all cells, whereas supralethal doses prevented the characteristic degradation of DNA into oligonucleosomal fragments. In contrast with aluminum phthalocyanine (AlPc) cells died by apoptosis after all doses studied. It appears that high PDT doses with Pc 4 or Pc 12 damage enzymes needed to carry out the program of apoptosis; the absence of this effect with AlPc suggests either a different intracellular location or different photocytotoxic mechanism for the two photosensitizers.

  13. Tensegrity finite element models of mechanical tests of individual cells.

    Science.gov (United States)

    Bursa, Jiri; Lebis, Radek; Holata, Jakub

    2012-01-01

    A three-dimensional finite element model of a vascular smooth muscle cell is based on models published recently; it comprehends elements representing cell membrane, cytoplasm and nucleus, and a complex tensegrity structure representing the cytoskeleton. In contrast to previous models of eucaryotic cells, this tensegrity structure consists of several parts. Its external and internal parts number 30 struts, 60 cables each, and their nodes are interconnected by 30 radial members; these parts represent cortical, nuclear and deep cytoskeletons, respectively. This arrangement enables us to simulate load transmission from the extracellular space to the nucleus or centrosome via membrane receptors (focal adhesions); the ability of the model was tested by simulation of some mechanical tests with isolated vascular smooth muscle cells. Although material properties of components defined on the basis of the mechanical tests are ambiguous, modelling of different types of tests has shown the ability of the model to simulate substantial global features of cell behaviour, e.g. "action at a distance effect" or the global load-deformation response of the cell under various types of loading. Based on computational simulations, the authors offer a hypothesis explaining the scatter of experimental results of indentation tests. PMID:22508025

  14. Molecular mechanisms underlying progesterone-enhanced breast cancer cell migration.

    Science.gov (United States)

    Wang, Hui-Chen; Lee, Wen-Sen

    2016-01-01

    Progesterone (P4) was demonstrated to inhibit migration in vascular smooth muscle cells (VSMCs), but to enhance migration in T47D breast cancer cells. To investigate the mechanism responsible for this switch in P4 action, we examined the signaling pathway responsible for the P4-induced migration enhancement in breast cancer cell lines, T47D and MCF-7. Here, we demonstrated that P4 activated the cSrc/AKT signaling pathway, subsequently inducing RSK1 activation, which in turn increased phosphorylation of p27 at T198 and formation of the p27pT198-RhoA complex in the cytosol, thereby preventing RhoA degradation, and eventually enhanced migration in T47D cells. These findings were confirmed in the P4-treated MCF-7. Comparing the P4-induced molecular events in between breast cancer cells and VSMCs, we found that P4 increased p27 phosphorylation at T198 in breast cancer cells through RSK1 activation, while P4 increased p27 phosphorlation at Ser10 in VSMCs through KIS activation. P27pT198 formed the complex with RhoA and prevented RhoA degradation in T47D cells, whereas p-p27Ser10 formed the complex with RhoA and caused RhoA degradation in VSMCs. The results of this study highlight the molecular mechanism underlying P4-enhanced breast cancer cell migration, and suggest that RSK1 activation is responsible for the P4-induced migration enhancement in breast cancer cells. PMID:27510838

  15. Effects and mechanisms of silibinin on human hepatoma cell lines

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    AIM: To investigate in vitro effects and mechanisms of silibinin on hepatocellular carcinoma (HCC) cell growth. METHODS: Human HCC cell lines were treated with different doses of silibinin. The effects of silibinin on HCC cell growth and proliferation, apoptosis, cell cycle progression, histone acetylation, and other related signal transductions were systematically examined. RESULTS: We demonstrated that silibinin significantly reduced the growth of HUH7, HepG2, Hep3B, and PLC/PRF/5 human hepatoma cells. Silibinin-reduced HuH7 cell growth was associated with significantly upregulated p21/CDK4 and p27/CDK4 complexes, downregulated Rb-phosphorylation and E2F1/DP1 complex. Silibinin promoted apoptosis of HuH7 cells that was associated with down-regulated survivin and upregulated activated caspase-3 and -9. Silibinin's anti angiogenic effects were indicated by down-regulated metalloproteinase-2 (MMP2) and CD34. We found that silibinin-reduced growth of HuH7 cells was associated with increased activity of phosphatase and tensin homolog deleted on chromosome ten (PTEN) and decreased p-Akt production, indicating the role of PTEN/ PI3K/Akt pathway in silibinin-mediated anti-HCC effects. We also demonstrated that silibinin increased acetylation of histone H3 and H4 (AC-H3 and AC-H4), indicating a possible role of altered histone acetylation in silibininreduced HCC cell proliferation.CONCLUSION: Our results defined silibinin's in vitro anti-HCC effects and possible mechanisms, and provided a rationale to further test silibinin for HCC chemoprevention.

  16. Primary and secondary T-cell lymphomas of the breast: clinico-pathologic features of 11 cases.

    Science.gov (United States)

    Gualco, Gabriela; Chioato, Lucimara; Harrington, William J; Weiss, Lawrence M; Bacchi, Carlos E

    2009-07-01

    Breast involvement by non-Hodgkin lymphomas is rare, and exceptional for T-cell lymphomas; we studied the morphologic, immunophenotypic, and clinical features of 11 patients with T-cell non-Hodgkin lymphomas involving the breast. Four cases fulfilled the definition criteria for primary breast lymphomas, 3 females and 1 male, with a median age of 51 years. One primary breast lymphomas was T-cell lymphoma unspecified, other was subcutaneous panniculitis-like T-cell lymphoma, and 2 cases were anaplastic large cell lymphomas. One of the anaplastic large cell lymphoma cases was found surrounding a silicone breast implant and presented as clinically as mastitis; whereas the other case occurred in a man. T-cell lymphoma secondarily involved the breast in 7 patients, all women and 1 bilateral, with a median age of 29 years. These secondary breast lymphomas occurred as part of widespread nodal or leukemic disease. Three patients had adult T-cell leukemia/lymphoma, including the patient with bilateral lesions, 3 others had precursor T-lymphoblastic lymphoma/leukemia, and the other presented with a peripheral-T-cell lymphoma non otherwise specified type. Breast T-cell lymphomas are very infrequent and are morphologically and clinically heterogeneous.

  17. Mechanisms and chemical induction of aneuploidy in rodent germ cells

    Energy Technology Data Exchange (ETDEWEB)

    Mailhes, J B; Marchetti, F

    2004-10-15

    The objective of this review is to suggest that the advances being made in our understanding of the molecular events surrounding chromosome segregation in non-mammalian and somatic cell models be considered when designing experiments for studying aneuploidy in mammalian germ cells. Accurate chromosome segregation requires the temporal control and unique interactions among a vast array of proteins and cellular organelles. Abnormal function and temporal disarray among these, and others to be inidentified, biochemical reactions and cellular organelles have the potential for predisposing cells to aneuploidy. Although numerous studies have demonstrated that certain chemicals (mainly those that alter microtubule function) can induce aneuploidy in mammalian germ cells, it seems relevant to point out that such data can be influenced by gender, meiotic stage, and time of cell-fixation post-treatment. Additionally, a consensus has not been reached regarding which of several germ cell aneuploidy assays most accurately reflects the human condition. More recent studies have shown that certain kinase, phosphatase, proteasome, and topoisomerase inhibitors can also induce aneuploidy in rodent germ cells. We suggest that molecular approaches be prudently incorporated into mammalian germ cell aneuploidy research in order to eventually understand the causes and mechanisms of human aneuploidy. Such an enormous undertaking would benefit from collaboration among scientists representing several disciplines.

  18. Ultrastructural characteristics of novel epithelial cell types identified in human pathologic liver specimens with chronic ductular reaction.

    OpenAIRE

    Vos, R.; Desmet, V

    1992-01-01

    Previous immunohistochemical studies on human liver biopsies with chronic ductular reaction revealed the presence of "small cells" with bile-duct type cytokeratin profile in the periportal area. This study identified similar cells by electron microscopy. The authors studied 13 human liver specimens with various liver diseases, but all characterized by chronic ductular reaction. In all specimens, variable numbers of "small cells" with common epithelial characteristics were identified in the pe...

  19. Hip-spine syndrome:pathological base and biomechanics mechanism%髋-腰综合征病理基础及生物力学机制

    Institute of Scientific and Technical Information of China (English)

    王强; 赵文杰; 张斌; 戴闽

    2015-01-01

    背景:研究发现,髋关节骨性关节炎患者全髋关节置换后下腰痛的症状得到一定缓解,提示下肢力线的改变对于腰痛症状具有明显的影响。目的:就髋-腰综合征的病理基础与生物力学机制进行综述并予以分析。方法:计算机检索1976年1月至2015年3月PubMed数据库、中国期刊全文数据库的相关文章,英文检索词“low back pain,hip-spine syndrome,hip osteoarthritis,total hip replacement,biomechanics,balance parameters”;中文检索词“下腰痛,髋-腰综合征,髋骨关节炎,髋关节置换,生物力学,平衡参数”。排除重复性研究及部分相关性较低的基础类文章。结果与结论:共计检索出145篇中英文文献,最终选择62篇文献进行综述。在病理生理中,肿瘤坏死因子α、白细胞介素1β和基质金属蛋白酶等对髋-腰综合征的发生发展起着十分重要的作用。而生物力学中,脊柱-骨盆-下肢平衡代偿过程成为髋-腰综合征的主要力学机制,其平衡参数可为髋-腰综合征的诊断,治疗及术后评估提供依据。%BACKGROUND:Low back pain in patients with hip osteoarthritis can be relieved to some extent after total hip arthroplasty, indicating the changes in limb line of force have obvious effects on low back pain. OBJECTIVE:To review and analysis the pathological base and biomechanics mechanism of hip-spine syndrome. METHODS: We retrieved PubMed database and China National Knowledge Infrastructure for related articles published from January 1976 to March 2015. The key words were “low back pain, hip-spine syndrome, hip osteoarthritis, total hip replacement, biomechanics, balance parameters” in English and Chinese, respectively. Repeated studies and unrelated articles were excluded. RESULTS AND CONCLUSION:A total of 145 articles were retrieved, and finaly 62 articles were enroled in result analysis. In the pathophysiology, tumor necrosis

  20. Regulatory mechanisms of apoptosis in regularly dividing cells

    Directory of Open Access Journals (Sweden)

    Ribal S Darwish

    2010-08-01

    Full Text Available Ribal S DarwishDepartment of Anesthesiology, Division of Critical Care Medicine, University of Maryland Medical Center, Baltimore, Maryland, USAAbstract: The balance between cell survival and death is essential for normal development and homeostasis of organisms. Apoptosis is a distinct type of cell death with ultrastructural features that are consistent with an active, inherently controlled process. Abnormalities and ­dysregulation of apoptosis contribute to the pathophysiology of multiple disease processes. Apoptosis is strictly regulated by several positive and negative feedback mechanisms that regulate cell death and determine the final outcome after cell exposure to apoptotic stimuli. Mitochondria and caspases are central components of the regulatory mechanisms of ­apoptosis. Recently, noncaspase pathways of apoptosis have been explored through the studies of ­apoptosis-inducing factor and endonuclease G. Multiple difficulties in the apoptosis research relate to apoptosis detection and imaging. This article reviews current understanding of the regulatory mechanisms of apoptosis.Keywords: caspases, apoptosis-inducing factor, apoptosis inhibitory proteins, cytochrome c, mitochondria 

  1. Tracking the mechanical dynamics of human embryonic stem cell chromatin

    Directory of Open Access Journals (Sweden)

    Hinde Elizabeth

    2012-12-01

    Full Text Available Abstract Background A plastic chromatin structure has emerged as fundamental to the self-renewal and pluripotent capacity of embryonic stem (ES cells. Direct measurement of chromatin dynamics in vivo is, however, challenging as high spatiotemporal resolution is required. Here, we present a new tracking-based method which can detect high frequency chromatin movement and quantify the mechanical dynamics of chromatin in live cells. Results We use this method to study how the mechanical properties of chromatin movement in human embryonic stem cells (hESCs are modulated spatiotemporally during differentiation into cardiomyocytes (CM. Notably, we find that pluripotency is associated with a highly discrete, energy-dependent frequency of chromatin movement that we refer to as a ‘breathing’ state. We find that this ‘breathing’ state is strictly dependent on the metabolic state of the cell and is progressively silenced during differentiation. Conclusions We thus propose that the measured chromatin high frequency movements in hESCs may represent a hallmark of pluripotency and serve as a mechanism to maintain the genome in a transcriptionally accessible state. This is a result that could not have been observed without the high spatial and temporal resolution provided by this novel tracking method.

  2. Quantification of stromal vascular cell mechanics with a linear cell monolayer rheometer

    Energy Technology Data Exchange (ETDEWEB)

    Elkins, Claire M., E-mail: cma9@stanford.edu; Fuller, Gerald G. [Department of Chemical Engineering, Stanford University, Stanford, California 94305 (United States); Shen, Wen-Jun; Khor, Victor K.; Kraemer, Fredric B. [Division of Endocrinology, Gerontology and Metabolism, Stanford University, Stanford, California 94305 and Veterans Affairs Palo Alto Health Care System, Palo Alto, California 94304 (United States)

    2015-01-15

    Over the past few decades researchers have developed a variety of methods for measuring the mechanical properties of whole cells, including traction force microscopy, atomic force microscopy (AFM), and single-cell tensile testing. Though each of these techniques provides insight into cell mechanics, most also involve some nonideal conditions for acquiring live cell data, such as probing only one portion of a cell at a time, or placing the cell in a nonrepresentative geometry during testing. In the present work, we describe the development of a linear cell monolayer rheometer (LCMR) and its application to measure the mechanics of a live, confluent monolayer of stromal vascular cells. In the LCMR, a monolayer of cells is contacted on both top and bottom by two collagen-coated plates and allowed to adhere. The top plate then shears the monolayer by stepping forward to induce a predetermined step strain, while a force transducer attached to the top plate collects stress information. The stress and strain data are then used to determine the maximum relaxation modulus recorded after step-strain, G{sub r}{sup 0}, referred to as the zero-time relaxation modulus of the cell monolayer. The present study validates the ability of the LCMR to quantify cell mechanics by measuring the change in G{sub r}{sup 0} of a confluent cell monolayer upon the selective inhibition of three major cytoskeletal components (actin microfilaments, vimentin intermediate filaments, and microtubules). The LCMR results indicate that both actin- and vimentin-deficient cells had ∼50% lower G{sub r}{sup 0} values than wild-type, whereas tubulin deficiency resulted in ∼100% higher G{sub r}{sup 0} values. These findings constitute the first use of a cell monolayer rheometer to quantitatively distinguish the roles of different cytoskeletal elements in maintaining cell stiffness and structure. Significantly, they are consistent with results obtained using single-cell mechanical testing methods

  3. Preventing effect of L-type calcium channel blockade on electrophysiological alterations in dentate gyrus granule cells induced by entorhinal amyloid pathology.

    Directory of Open Access Journals (Sweden)

    Hamid Gholami Pourbadie

    Full Text Available The entorhinal cortex (EC is one of the earliest affected brain regions in Alzheimer's disease (AD. EC-amyloid pathology induces synaptic failure in the dentate gyrus (DG with resultant behavioral impairment, but there is little known about its impact on neuronal properties in the DG. It is believed that calcium dyshomeostasis plays a pivotal role in the etiology of AD. Here, the effect of the EC amyloid pathogenesis on cellular properties of DG granule cells and also possible neuroprotective role of L-type calcium channel blockers (CCBs, nimodipine and isradipine, were investigated. The amyloid beta (Aβ 1-42 was injected bilaterally into the EC of male rats and one week later, electrophysiological properties of DG granule cells were assessed. Voltage clamp recording revealed appearance of giant sIPSC in combination with a decrease in sEPSC frequency which was partially reversed by CCBs in granule cells from Aβ treated rats. EC amyloid pathogenesis induced a significant reduction of input resistance (Rin accompanied by a profound decreased excitability in the DG granule cells. However, daily administration of CCBs, isradipine or nimodipine (i.c.v. for 6 days, almost preserved the normal excitability against Aβ. In conclusion, lower tendency to fire AP along with reduced Rin suggest that DG granule cells might undergo an alteration in the membrane ion channel activities which finally lead to the behavioral deficits observed in animal models and patients with early-stage Alzheimer's disease.

  4. Mechanical behaviour of PEM fuel cell catalyst layers during regular cell operation

    Directory of Open Access Journals (Sweden)

    Maher A.R. Sadiq Al-Baghdadi

    2010-11-01

    Full Text Available Damage mechanisms in a proton exchange membrane fuel cell are accelerated by mechanical stresses arising during fuel cell assembly (bolt assembling, and the stresses arise during fuel cell running, because it consists of the materials with different thermal expansion and swelling coefficients. Therefore, in order to acquire a complete understanding of the mechanical behaviour of the catalyst layers during regular cell operation, mechanical response under steady-state hygro-thermal stresses should be studied under real cell operating conditions and in real cell geometry (three-dimensional. In this work, full three-dimensional, non-isothermal computational fluid dynamics model of a PEM fuel cell has been developed to investigate the behaviour of the cathode and anode catalyst layers during the cell operation. A unique feature of the present model is to incorporate the effect of hygro and thermal stresses into actual three-dimensional fuel cell model. In addition, the temperature and humidity dependent material properties are utilize in the simulation for the membrane. The model is shown to be able to understand the many interacting, complex electrochemical, transport phenomena, and deformation that have limited experimental data.

  5. The Danish Pathology Register

    DEFF Research Database (Denmark)

    Bjerregaard, Beth; Larsen, Ole B

    2011-01-01

    The National Board of Health, Denmark in 1997 published guidelines for reporting of pathology data and the Danish Pathology Register (DPR) was established.......The National Board of Health, Denmark in 1997 published guidelines for reporting of pathology data and the Danish Pathology Register (DPR) was established....

  6. Role of Ink4a/Arf Locus in Beta Cell Mass Expansion under Physiological and Pathological Conditions

    Science.gov (United States)

    Salas, Elisabet; Rabhi, Nabil; Froguel, Philippe; Annicotte, Jean-Sébastien

    2014-01-01

    The ARF/INK4A (Cdkn2a) locus includes the linked tumour suppressor genes p16INK4a and p14ARF (p19ARF in mice) that trigger the antiproliferative activities of both RB and p53. With beta cell self-replication being the primary source for new beta cell generation in adult animals, the network by which beta cell replication could be increased to enhance beta cell mass and function is one of the approaches in diabetes research. In this review, we show a general view of the regulation points at transcriptional and posttranslational levels of Cdkn2a locus. We describe the molecular pathways and functions of Cdkn2a in beta cell cycle regulation. Given that aging reveals increased p16Ink4a levels in the pancreas that inhibit the proliferation of beta cells and decrease their ability to respond to injury, we show the state of the art about the role of this locus in beta cell senescence and diabetes development. Additionally, we focus on two approaches in beta cell regeneration strategies that rely on Cdkn2a locus negative regulation: long noncoding RNAs and betatrophin. PMID:24672805

  7. Role of Ink4a/Arf Locus in Beta Cell Mass Expansion under Physiological and Pathological Conditions

    Directory of Open Access Journals (Sweden)

    Elisabet Salas

    2014-01-01

    Full Text Available The ARF/INK4A (Cdkn2a locus includes the linked tumour suppressor genes p16INK4a and p14ARF (p19ARF in mice that trigger the antiproliferative activities of both RB and p53. With beta cell self-replication being the primary source for new beta cell generation in adult animals, the network by which beta cell replication could be increased to enhance beta cell mass and function is one of the approaches in diabetes research. In this review, we show a general view of the regulation points at transcriptional and posttranslational levels of Cdkn2a locus. We describe the molecular pathways and functions of Cdkn2a in beta cell cycle regulation. Given that aging reveals increased p16Ink4a levels in the pancreas that inhibit the proliferation of beta cells and decrease their ability to respond to injury, we show the state of the art about the role of this locus in beta cell senescence and diabetes development. Additionally, we focus on two approaches in beta cell regeneration strategies that rely on Cdkn2a locus negative regulation: long noncoding RNAs and betatrophin.

  8. Investigating cell death mechanisms in Amyotrophic lateral sclerosis using transcriptomics

    Directory of Open Access Journals (Sweden)

    Paul Roy Heath

    2013-12-01

    Full Text Available Amyotrophic lateral sclerosis is a motor neuron disease characterised by degeneration and loss of upper and lower motor neurons from the motor cortex, brainstem and spinal cord although evidence is suggesting that there is further involvement of other cell types in the surrounding tissue. Transcriptomic analysis by gene expression profiling using microarray technology has enabled the determination of patterns of cell death in the degenerating tissues. This work has examined gene expression at the level of the tissue and individual cell types in both sporadic and familial forms of the disease. In addition, further studies have examined the differential vulnerability of neuronal cells in different regions of the central nervous system. Model systems have also provided further information to help unravel the mechanisms that lead to death of the motor neurons in disease and also provided novel insights. In this review we shall describe the methods that have been used in these investigations and describe how they have contributed to our knowledge of the cell death mechanisms in ALS.

  9. Pathologic assessment of myocardial cell necrosis and apoptosis after ischemia and reperfusion with molecular and morphological markers.

    Science.gov (United States)

    Takashi, E; Ashraf, M

    2000-02-01

    The present work illustrates the critical subcellular changes in the rat heart after 10-30 min of left coronary artery (LCA) occlusion and 120 min of reperfusion with a combination of several staining techniques. Triphenyltetrazolium chloride (TTC) to detect non-injured myocytes, horseradish peroxidase (HRP) and terminal deoxynucleotide nick-end labeling (TUNEL) to detect necrotic and apoptotic cells were employed and electron microscopy (EM) was used to validate these changes. After 20 min of LCA occlusion, myocytes began to undergo necrosis whilst after 10 min occlusion, no myocyte underwent irreversible cell injury in the risk area. After 30 min of LCA occlusion and 120 min reperfusion, 36.3, 26.6 and 25% cells were normal, necrotic, and reversibly injured, respectively; the remaining 12.8% cells were apoptotic. Necrotic cells were strongly positive with HRP and negative for TTC and TUNEL. TUNEL-positive or apoptotic cells were slightly HRP-positive, indicating altered cell membrane permeability. Reversibly-injured myocytes were TTC-, HRP- and TUNEL-negative. These changes were more accurately defined in the 100- microm thick sections than in the traditional slices. It is concluded that: (1) TTC-staining of 100- microm thick sections is far superior and accurate for the detection of ischemic changes with shorter period of ischemia (10 min); (2) the combination of TTC-staining, HRP reaction and TUNEL method is excellent for demarcation of early ischemic changes; (3) TTC-negativity in ischemia less than 20 min does not indicate necrosis but only represents reversible changes; (4) the apoptosis is absent in early ischemia of 20 min with or without reperfusion at a time when sufficient ATP is present, and appears only after 30 min of coronary ligation and reperfusion; and (5) the apoptotic cells lose membrane integrity accompanied by decreased glycocalyx thickness and cell swelling as opposed to commonly known characteristics of apoptotic cells. PMID:10722798

  10. Mechanical-Electrochemical-Thermal Simulation of Lithium-Ion Cells

    Energy Technology Data Exchange (ETDEWEB)

    Santhanagopalan, Shriram; Zhang, Chao; Sprague, Michael A.; Pesaran, Ahmad

    2016-06-01

    Models capture the force response for single-cell and cell-string levels to within 15%-20% accuracy and predict the location for the origin of failure based on the deformation data from the experiments. At the module level, there is some discrepancy due to poor mechanical characterization of the packaging material between the cells. The thermal response (location and value of maximum temperature) agrees qualitatively with experimental data. In general, the X-plane results agree with model predictions to within 20% (pending faulty thermocouples, etc.); the Z-plane results show a bigger variability both between the models and test-results, as well as among multiple repeats of the tests. The models are able to capture the timing and sequence in voltage drop observed in the multi-cell experiments; the shapes of the current and temperature profiles need more work to better characterize propagation. The cells within packaging experience about 60% less force under identical impact test conditions, so the packaging on the test articles is robust. However, under slow-crush simulations, the maximum deformation of the cell strings with packaging is about twice that of cell strings without packaging.

  11. On the Mechanism of Light Transmission by Muller Cells

    CERN Document Server

    Makarov, Vladimir; Khmelinskii, Igor; Inyushin, Mikhail

    2015-01-01

    We report that Muller cells contain bundles of long specialized intermediate filaments about 10 nm in diameter; most likely, these filaments are the channels providing light transmission to photoreceptor cells in mammalian and avian retinas. We interpret transmission of light in such channels using the notions of quantum confinement, describing energy transport in structures with electro-conductive walls and diameter much smaller than the wavelength of the respective photons. Model calculations produce photon transmission efficiency in such channels exceeding 0.8, in optimized geometry. We infer that protein molecules make up the channels, proposing a qualitative mechanism of light transmission by such structures.

  12. Mechanism of yeast cell photoinactivation by visible light

    International Nuclear Information System (INIS)

    The nature of inactivation of visible light without sensitizers added to the cells has been investigated. In particular, the problem on the nature of intracellular sensitizers has been studied. Visible light is shown to inactivate the cells only in the presence of oxygen, that gives evidence that the process of photoinactivation is carried out according a photodynamic mechanism with participation of the endogenic sensitizer. The pigment - sensitizer is identified as the protoporphyrin on the basis of comparison of data obtained for the absorption spectrum structure and pigment fluorescence with the literature data on the spectral properties of porphyrin compounds

  13. Degeneration and regeneration of the olfactory epithelium following inhalation exposure to methyl bromide: pathology, cell kinetics, and olfactory function.

    Science.gov (United States)

    Hurtt, M E; Thomas, D A; Working, P K; Monticello, T M; Morgan, K T

    1988-06-30

    The effects of acute inhalation exposure to methyl bromide (MeBr) on the olfactory epithelium of male F-344 rats was investigated by morphologic examination of animals killed at varying timepoints during and following exposure to 200 ppm MeBr 6 hr/day for 5 days. Cell replication rate and histopathology were used to assess the kinetics of repair. In addition, olfactory function, using the buried food pellet test, was assessed and the result compared with morphological recovery. Extensive destruction of the olfactory epithelium was evident in animals killed directly after a single 6-hr exposure to MeBr. Histologic features of these lesions indicate that the primary, or most severe, effect of MeBr exposure was on the sustentacular cells and mature sensory cells; basal cells were generally unaffected. By Day 3, despite continued exposure, there was replacement of the olfactory epithelium by a squamous cell layer that increased in thickness and basophilic cytoplasmic staining over the next 2 days of exposure. One week postexposure, the epithelial region was covered by a layer of polyhedral, basophilic cells, and from 2 to 10 weeks postexposure, the epithelium exhibited progressive reorganization to reform the original olfactory epithelium pattern. By Week 10, 75-80% of the olfactory epithelium appeared morphologically normal. Cell replication showed a single peak of olfactory epithelial cell proliferation at Day 3 of exposure, with a labeling index of 14.5% compared to 0.7% in controls. Cell replication rates returned gradually to control levels by Week 10 postexposure. Behavioral tests of olfactory function in animals after a single 6-hr exposure to 200 ppm MeBr demonstrated a loss of the sense of smell, with recovery of this function by Day 6. Exposure to 90 ppm caused no observable effect on olfactory function or morphology. These findings demonstrate that the olfactory mucosa is highly sensitive to the toxic effects of MeBr and that olfactory epithelial cell

  14. Mechanisms of Dendritic Cell Lysosomal Killing of Cryptococcus

    Science.gov (United States)

    Hole, Camaron R.; Bui, Hoang; Wormley, Floyd L.; Wozniak, Karen L.

    2012-10-01

    Cryptococcus neoformans is an opportunistic pulmonary fungal pathogen that disseminates to the CNS causing fatal meningitis in immunocompromised patients. Dendritic cells (DCs) phagocytose C. neoformans following inhalation. Following uptake, cryptococci translocate to the DC lysosomal compartment and are killed by oxidative and non-oxidative mechanisms. DC lysosomal extracts kill cryptococci in vitro; however, the means of antifungal activity remain unknown. Our studies determined non-oxidative antifungal activity by DC lysosomal extract. We examined DC lysosomal killing of cryptococcal strains, anti-fungal activity of purified lysosomal enzymes, and mechanisms of killing against C. neoformans. Results confirmed DC lysosome fungicidal activity against all cryptococcal serotypes. Purified lysosomal enzymes, specifically cathepsin B, inhibited cryptococcal growth. Interestingly, cathepsin B combined with its enzymatic inhibitors led to enhanced cryptococcal killing. Electron microscopy revealed structural changes and ruptured cryptococcal cell walls following treatment. Finally, additional studies demonstrated that osmotic lysis was responsible for cryptococcal death.

  15. Fatigue and Mechanical Damage Propagation in Automotive PEM Fuel Cells

    Science.gov (United States)

    Banan, Roshanak

    Polymer electrolyte membrane (PEM) fuel cells are generally exposed to high magnitude road-induced vibrations and impact loads, frequent humidity-temperature loading cycles, and freeze/thaw stresses when employed in automotive applications. The resultant mechanical stresses can play a significant role in the evolution of mechanical defects in the membrane electrode assembly (MEA). The focus of this research is to investigate fatigue challenges due to humidity-temperature (hygrothermal) cycles and vibrations and their effects on damage evolution in PEM fuel cells. To achieve this goal, this thesis is divided into three parts that provide insight into damage propagation in the MEA under i) hygrothermal cycles, ii) external applied vibrations, and iii) a combination of both to simulate realistic automotive conditions. A finite element damage model based on cohesive zone theory was developed to simulate the propagation of micro-scale defects (cracks and delaminations) in the MEA under fuel cell operating conditions. It was found that the micro-defects can propagate to critical states under start-up and shut-down cycles, prior to reaching the desired lifespan of the fuel cell. The simultaneous presence of hygrothermal cycles and vibrations severely intensified damage propagation and resulted in considerably large defects within 75% of the fuel cell life expectancy. However, the order of generated damage was found to be larger under hygrothermal cycles than vibrations. Under hygrothermal cycles, membrane crack propagation was more severe compared to delamination propagation. Conversely, the degrading influence of vibrations was more significant on delaminations. The presence of an anode/cathode channel offset under the combined loadings lead to a 2.5-fold increase in the delamination length compared to the aligned-channel case. The developed model can be used to investigate the damage behaviour of current materials employed in fuel cells as well as to evaluate the

  16. Cell-Autonomous Effector Mechanisms against Mycobacterium tuberculosis

    OpenAIRE

    MacMicking, John D.

    2014-01-01

    Few pathogens run the gauntlet of sterilizing immunity like Mycobacterium tuberculosis (Mtb). This organism infects mononuclear phagocytes and is also ingested by neutrophils, both of which possess an arsenal of cell-intrinsic effector mechanisms capable of eliminating it. Here Mtb encounters acid, oxidants, nitrosylating agents, and redox congeners, often exuberantly delivered under low oxygen tension. Further pressure is applied by withholding divalent Fe2+, Mn2+, Cu2+, and Zn2+, as well as...

  17. Cell model for efficient simulation of wave propagation in human ventricular tissue under normal and pathological conditions

    Energy Technology Data Exchange (ETDEWEB)

    Tusscher, K H W J Ten; Panfilov, A V [Department of Theoretical Biology, Utrecht University, Padualaan 8, 3584 CH Utrecht (Netherlands)

    2006-12-07

    In this paper, we formulate a model for human ventricular cells that is efficient enough for whole organ arrhythmia simulations yet detailed enough to capture the effects of cell level processes such as current blocks and channelopathies. The model is obtained from our detailed human ventricular cell model by using mathematical techniques to reduce the number of variables from 19 to nine. We carefully compare our full and reduced model at the single cell, cable and 2D tissue level and show that the reduced model has a very similar behaviour. Importantly, the new model correctly produces the effects of current blocks and channelopathies on AP and spiral wave behaviour, processes at the core of current day arrhythmia research. The new model is well over four times more efficient than the full model. We conclude that the new model can be used for efficient simulations of the effects of current changes on arrhythmias in the human heart.

  18. A microfluidic platform for systems pathology: multiparameter single-cell signaling measurements of clinical brain tumor specimens

    OpenAIRE

    Sun, Jing; Masterman-Smith, Michael; Graham, Nicholas A; Jiao, Jing; Mottahedeh, Jack; Laks, Dan R.; Ohashi, Minori; DeJesus, Jason; Kamei, Ken-ichiro; Lee, Ki-Bum; Wang, Hao; Yu, Zeta T.F.; Lu, Yi-Tsung; Hou, Shuang; Li,Keyu

    2010-01-01

    The clinical practice of oncology is being transformed by molecular diagnostics that will enable predictive and personalized medicine. Current technologies for quantitation of the cancer proteome are either qualitative (e.g., immunohistochemistry) or require large sample sizes (e.g., flow cytometry). Here, we report a microfluidic platform, Microfluidic Image Cytometry (MIC), capable of quantitative, single-cell proteomic analysis of multiple signaling molecules using only 1,000-2,800 cells. ...

  19. A Case of Successful Remission of Extensive Primary Gastric Diffuse Large B Cell Lymphoma: Radiologic, Endoscopic and Pathologic Evidence

    Directory of Open Access Journals (Sweden)

    Mike M. Bismar

    2014-04-01

    Full Text Available Though rare amongst stomach neoplasms, primary gastric diffuse large B cell lymphoma is one of the commonest extranodal non-Hodgkin lymphomas. If left untreated, it can have a devastating progression and life-threatening consequences. We present the case of a successfully treated large antral ulcer confirmed to be large B cell lymphoma as evidenced by radiologic, endoscopic and histopathologic findings. A brief discussion about the types of gastric lymphoma, their Helicobacter pylori relation and therapeutic modalities follows.

  20. Bystander responses in cells models; targets, dosimetry and mechanisms

    International Nuclear Information System (INIS)

    The use of microbeam approaches has been a major advance in probing the relevance of bystander responses in cell and tissue models. Our own studies at the Gray Cancer Institute have used both a charged particle microbeam, producing protons and helium ions and a soft X-ray microprobe, delivering focused carbon-K, aluminium-K and titanium-K soft X-rays. Using these techniques we have been able to build up a comprehensive picture of the underlying differences between bystander responses and direct effects in cell and tissue-like models. What is now clear is that bystander dose-response relationships, the underlying mechanisms of action and the targets involved are not the same as those observed for direct irradiation of DNA in the nucleus. Our recent studies have shown bystander responses induced in human or hamster cells even when radiation is deposited away from the nucleus in cytoplasmic targets either after charged particle or soft X-ray exposure. Importantly, the level of bystander effect, measured as cell killing was similar to that observed when the same amount of energy was deposited but targeted to the nucleus. In other studies, we have shown that underlying determination of the level of response is the energy deposited in a single cell rather than the number of cells hit. Also the overall response at low doses may be dominated by bystander signaling. These observations have significance for our understanding of radiation risk at low doses including those of environmental exposures and the applicability of the Linear Non Threshold model. The realization that cell to cell signaling is important for radiation response may also open up new therapeutic opportunities to either improve tumor cell kill or protect normal tissues if the pathways underpinning bystander signaling can be elucidated and controlled

  1. Role of ROBO4 Signalling in Developmental and Pathological Angiogenesis

    Directory of Open Access Journals (Sweden)

    Suresh Singh Yadav

    2014-01-01

    Full Text Available Transmembrane roundabout receptor family members (ROBO1–ROBO4 principally orchestrate the neuronal guidance mechanism of the nervous system. Secreted glycoprotein SLITs are the most appreciated ligands for ROBOs. Recently identified ROBO4 is the key mediator of SLIT-ROBO mediated developmental and pathological angiogenesis. Although SLIT2 has been shown to interact with ROBO4 as ligand, it remains an open question whether this protein is the physiologic partner of ROBO4. The purpose of this review is to summarise how reliable SLIT2 as ligand for ROBO4 is, if not what the other possible mechanisms demonstrated till date for ROBO4 mediated developmental and pathological angiogenesis are. We conclude that ROBO4 is expressed specially in vascular endothelial cells and maintains the vascular integrity via either SLIT2 dependent or SLIT2 independent manner. On the contrary, it promotes the pathological angiogenesis by involving different signalling arm(s/unknown ligand(s. This review explores the interactions SLIT2/ROBO1, SLIT2/ROBO1–ROBO4, ROBO1/ROBO4, and ROBO4/UNC5B which can be promising and potential therapeutic targets for developmental angiogenesis defects and pathological angiogenesis. Finally we have reviewed the ROBO4 signalling pathways and made an effort to elaborate the insight of this signalling as therapeutic target of pathological angiogenesis.

  2. Regenerating medicine related to the stem-cells and its mechanisms of action from adults cells

    International Nuclear Information System (INIS)

    Regenerating medicine is a branch of Medicine very developed in past years. Advances in this field have been closely linked with the new knowledge achieved on stem-cells and its ability to become in cells of different tissues. This type of medicine is based on the behaviors adopted by organism to substitute those damaged cells by the healthy ones by different processes in specific tissues. Therapeutic measures used may include the stem-cell transplantation, the use of soluble molecules, genic therapy and tissues engineering. Nowadays, the more used method is the adult stem-cells. However, is not well known the mechanisms by which the transplanted cells could to improve or to promote the tissue regeneration. To explain these mechanisms some hypotheses has been proposed including the cellular trans-differentiation, cells fusion, and the effects secondaries to cells release by cells of different soluble molecules with specific actions; in addition to the autocrine and paracrine effects that may have these soluble factors, it is suggested too the existence of a telecrine action. It is probable that more than one of these mechanisms be executed

  3. Paracrine Mechanisms of Mesenchymal Stem Cells in Tissue Repair.

    Science.gov (United States)

    Gnecchi, Massimiliano; Danieli, Patrizia; Malpasso, Giuseppe; Ciuffreda, Maria Chiara

    2016-01-01

    Tissue regeneration from transplanted mesenchymal stromal cells (MSC) either through transdifferentiation or cell fusion was originally proposed as the principal mechanism underlying their therapeutic action. However, several studies have now shown that both these mechanisms are very inefficient. The low MSC engraftment rate documented in injured areas also refutes the hypothesis that MSC repair tissue damage by replacing cell loss with newly differentiated cells. Indeed, despite evidence of preferential homing of MSC to the site of myocardial ischemia, exogenously administered MSC show poor survival and do not persist in the infarcted area. Therefore, it has been proposed that the functional benefits observed after MSC transplantation in experimental models of tissue injury might be related to the secretion of soluble factors acting in a paracrine fashion. This hypothesis is supported by pre-clinical studies demonstrating equal or even improved organ function upon infusion of MSC-derived conditioned medium (MSC-CM) compared with MSC transplantation. Identifying key MSC-secreted factors and their functional role seems a reasonable approach for a rational design of nextgeneration MSC-based therapeutics. Here, we summarize the major findings regarding both different MSC-mediated paracrine actions and the identification of paracrine mediators. PMID:27236669

  4. Obstructive renal injury: from fluid mechanics to molecular cell biology

    Directory of Open Access Journals (Sweden)

    Alvaro C Ucero

    2010-04-01

    Full Text Available Alvaro C Ucero1,*, Sara Gonçalves2,*, Alberto Benito-Martin1, Beatriz Santamaría1, Adrian M Ramos1, Sergio Berzal1, Marta Ruiz-Ortega1, Jesus Egido1, Alberto Ortiz11Fundación Jiménez Díaz, Universidad Autónoma de Madrid, Fundación Renal Iñigo Alvarez de Toledo, Madrid, Spain; 2Nefrologia e Transplantação Renal, Hospital de Santa Maria EPE, Lisbon, Portugal *Both authors contributed equally to the manuscriptAbstract: Urinary tract obstruction is a frequent cause of renal impairment. The physiopathology of obstructive nephropathy has long been viewed as a mere mechanical problem. However, recent advances in cell and systems biology have disclosed a complex physiopathology involving a high number of molecular mediators of injury that lead to cellular processes of apoptotic cell death, cell injury leading to inflammation and resultant fibrosis. Functional studies in animal models of ureteral obstruction using a variety of techniques that include genetically modified animals have disclosed an important role for the renin-angiotensin system, transforming growth factor-β1 (TGF-β1 and other mediators of inflammation in this process. In addition, high throughput techniques such as proteomics and transcriptomics have identified potential biomarkers that may guide clinical decision-making.Keywords: urinary tract obstruction, renal injury, fluid mechanics, molecular cell biology

  5. Cell Patterning for Liver Tissue Engineering via Dielectrophoretic Mechanisms

    Directory of Open Access Journals (Sweden)

    Wan Nurlina Wan Yahya

    2014-07-01

    Full Text Available Liver transplantation is the most common treatment for patients with end-stage liver failure. However, liver transplantation is greatly limited by a shortage of donors. Liver tissue engineering may offer an alternative by providing an implantable engineered liver. Currently, diverse types of engineering approaches for in vitro liver cell culture are available, including scaffold-based methods, microfluidic platforms, and micropatterning techniques. Active cell patterning via dielectrophoretic (DEP force showed some advantages over other methods, including high speed, ease of handling, high precision and being label-free. This article summarizes liver function and regenerative mechanisms for better understanding in developing engineered liver. We then review recent advances in liver tissue engineering techniques and focus on DEP-based cell patterning, including microelectrode design and patterning configuration.

  6. Analysis of loss mechanisms in polycrystalline thin film solar cells

    Science.gov (United States)

    Sites, J. R.

    1990-08-01

    Our goal for thin-film polycrystalline solar cell analysis was to increase the useful information extracted from relatively straightforward electrical measurements. The strategy was to (1) systematize measurements and reporting, (2) organize results in terms of quantitative values for individual sources of current and voltage loss, and (3) evaluate possible analytical techniques to enhance precision and avoid pitfalls, and (4) insist on a viable physical explanation of each loss mechanism. Current-voltage, quantum efficiency, and capacitance measurements on CuInSe2 and CdTe solar cells from a variety of sources have been analyzed. In many cases losses were identified that may be lessened relatively easily. However, the operating voltage loss due to excessive forward recombination current throughout the depletion region remains the primary obstacle to efficiencies competitive with single crystal cells.

  7. Analysis of loss mechanisms in polycrystalline thin film solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Sites, J.R. (Colorado State Univ., Fort Collins, CO (USA))

    1990-08-01

    Our goal for thin-film polycrystalline solar cell analysis was to increase the useful information extracted from relatively straightforward electrical measurements. The strategy was to (1) systematize measurements and reporting, (2) organize results in terms of quantitative values for individual sources of current and voltage loss, and (3) evaluate possible analytical techniques to enhance precision and avoid pitfalls, and (4) insist on a viable physical explanation of each loss mechanism. Current-voltage, quantum efficiency, and capacitance measurements on CuInSe{sub 2} and CdTe solar cells from a variety of sources have been analyzed. In many cases losses were identified that may be lessened relatively easily. However, the operating voltage loss due to excessive forward recombination current throughout the depletion region remains the primary obstacle to efficiencies competitive with single crystal cells. 1 tab., 4 figs., 26 refs.

  8. Cell Biological Mechanisms of Multidrug Resistance in Tumors

    Science.gov (United States)

    Simon, Sanford M.; Schindler, Melvin

    1994-04-01

    Multidrug resistance (MDR) is a generic term for the variety of strategies tumor cells use to evade the cytotoxic effects of anticancer drugs. MDR is characterized by a decreased sensitivity of tumor cells not only to the drug employed for chemotherapy but also to a broad spectrum of drugs with neither obvious structural homology nor common targets. This pleotropic resistance is one of the major obstacles to the successful treatment of tumors. MDR may result from structural or functional changes at the plasma membrane or within the cytoplasm, cellular compartments, or nucleus. Molecular mechanisms of MDR are discussed in terms of modifications in detoxification and DNA repair pathways, changes in cellular sites of drug sequestration, decreases in drug-target affinity, synthesis of specific drug inhibitors within cells, altered or inappropriate targeting of proteins, and accelerated removal or secretion of drugs.

  9. Glomerulonephritis associated with marginal zone B-cell lymphoma: clinical, pathological characteristics of renal injury and treatment (clinical cases

    Directory of Open Access Journals (Sweden)

    B. T. Dzhumabaeva

    2015-12-01

    Full Text Available Glomerulonephritis associated with marginal zone B-cell lymphoma at the onset of disease is rarely diagnosed. In this article we reported two patient of the extranodal marginal zone B-cell lymphoma with kidney damage. The first patient with the extranodal marginal zone B-cell lymphoma involved the stomach, lymph nodes, bone marrow and associated with mesangioproliferative glomerulonephritis and renal failure. The second patient with the splenic form of marginal zone B-cell lymphoma associated with fibrillary glomerulonephritis and hepatitis C and involve the lymph nodes, liver, bone marrow, and synthesis monoclonal immunoglobulin (IgMκ, cryoglobulin type II. Glomerulonephritis of the both cases were established on the renal biopsies by the morphological investigation, immunofluorescence, and electron microscopy.Both patients received therapy with bendamustine and rituximab, which has resulted in complete remission for lymphatic tumors and improve of kidney function. Overall and event-free survival in the first case corresponds to 21 and 16 months, the second 29 and 20, respectively.These cases illustrates that the kidney may be initially involved by extranodal marginal zone B-cell lymphoma, and the need for expanded investigation of the possible dissemination. Combination of bendamustine and rituximab were effective and safety treatment in these cases.

  10. Age related changes in pancreatic beta cells: A putative extra-cerebral site of Alzheimer’s pathology

    Science.gov (United States)

    Maj, Magdalena; Ilhan, Aysegul; Neziri, Dashurie; Gartner, Wolfgang; Berggard, Tord; Attems, Johannes; Base, Wolfgang; Wagner, Ludwig

    2011-01-01

    Frequent concomitant manifestation of type 2 diabetes mellitus (T2DM) and Alzheimer’s disease (AD) has been recently demonstrated by epidemiological studies. This might be due to functional similarities between β-cells and neurons, such as secretion on demand of highly specific molecules in a tightly controlled fashion. An additional similarity represents the age-related alteration of hyperphosphorylated tau in AD patients. Similarly, alterations have been identified in β-cells of T2DM patients. The islet amyloid polypeptide has been associated with β-cell apoptosis. As a consequence of increasing age, the accumulation of highly modified proteins together with decreased regenerative potential might lead to increasing rates of apoptosis. Moreover, reduction of β-cell replication capabilities results in reduction of β-cell mass in mammals, simultaneously with impaired glucose tolerance. The new challenge is to learn much more about age-related protein modifications. This can lead to new treatment strategies for reducing the incidence of T2DM and AD. PMID:21537460

  11. Chorein Sensitivity of Actin Polymerization, Cell Shape and Mechanical Stiffness of Vascular Endothelial Cells

    Directory of Open Access Journals (Sweden)

    Ioana Alesutan

    2013-09-01

    Full Text Available Background/Aims: Endothelial cell stiffness plays a key role in endothelium-dependent control of vascular tone and arterial blood pressure. Actin polymerization and distribution of microfilaments is essential for mechanical cell stiffness. Chorein, a protein encoded by the VPS13A gene, defective in chorea-acanthocytosis (ChAc, is involved in neuronal cell survival as well as cortical actin polymerization of erythrocytes and blood platelets. Chorein is expressed in a wide variety of further cells, yet nothing is known about the impact of chorein on cells other than neurons, erythrocytes and platelets. The present study explored whether chorein is expressed in human umbilical vein endothelial cells (HUVECs and addressed the putative role of chorein in the regulation of cytoskeletal architecture, stiffness and survival of those cells. Methods: In HUVECs with or without silencing of the VPS13A gene, VPS13A mRNA expression was determined utilizing quantitative RT-PCR, cytoskeletal organization visualized by confocal microscopy, G/F actin ratio and phosphorylation status of focal adhesion kinase quantified by western blotting, cell death determined by flow cytometry, mechanical properties studied by atomic force microscopy (AFM and cell morphology analysed by scanning ion conductance microscopy (SICM. Results: VPS13A mRNA expression was detectable in HUVECs. Silencing of the VPS13A gene attenuated the filamentous actin network, decreased the ratio of soluble G-actin over filamentous F-actin, reduced cell stiffness and changed cell morphology as compared to HUVECs silenced with negative control siRNA. These effects were paralleled by a significant decrease in FAK phosphorylation following VPS13A silencing. Moreover, silencing of the VPS13A gene increased caspase 3 activity and induced necrosis in HUVECs. Conclusions: Chorein is a novel regulator of cytoskeletal architecture, cell shape, mechanical stiffness and survival of vascular endothelial cells.

  12. Cell-structure and mechanical properties of closed-cell aluminum foam

    Institute of Scientific and Technical Information of China (English)

    ZHOU Yun(周芸); ZUO Xiao-qing(左孝青); SUN Jia-lin(孙加林); S.R.Nutt

    2004-01-01

    The density, cell size and structure of closed-cell aluminum foam were measured by optical microscopy and image analysis. The properties and the mechanism of compressive deformation that occur in closed-cell aluminum foam were measured and discussed. The results show that the cell size of foam with density of 0.37 mg/m3 is distributed in the range of 0.5 - 4.0 mm. The cell size of foam with density of 0.33 mg/m3 is distributed in the range of 0.5 - 5.0 mm. The cell wall thickness of both types is 0.1 - 0.3 mm. The closed-cell aluminum foam almost belongs to isotropic one, with a variation of ±15% in elastic modulus and yield strength in longitudinal and transverse direction. Under compressive loading, foam materials show inhomogeneous macroscopic deformation. The site of the onset of local plastic deformation depends on the cell structure. The shape of cell is more important than size in determining the yielding susceptibility of the cells. At early stage of deformation,the deformation is localized in narrow bands having width of one cell's diameter, and outside the bands the cell still remains the original shape. The cells within bands experience large permanent deformation. The band normals are usually within 20° of the loading axis.

  13. Pulmonary langerhans cell histiocytosis in adults: high-resolution CT - pathology comparisons and evolutional changes at CT

    International Nuclear Information System (INIS)

    To compare high-resolution (HR) CT and histopathological findings and to evaluate serial CT findings in pulmonary Langerhans cell histiocytosis (PLCH). We reviewed CT of lung lesions in 27 adults (M:F = 20:7, mean age, 41 ± 12.3 years) with PLCH. After evaluating lung abnormalities including nodules, micronodules, thick-walled, thin-walled, and bizarre-shaped cysts and reticulation, observers compared CT findings obtained at lung biopsy sites with histopathological findings. The final CT was compared with the initial CT to determine disease extent changes. The most frequently observed patterns of lung abnormalities were micronodules (n = 24, 89%), thick-walled (n = 22, 82%), and thin-walled (n = 22, 82%) cysts. Even thin-walled and bizarre cysts harboured active inflammatory Langerhans cell sheets and eosinophils in their walls. In thin-walled cysts, we noted pericystic inflammatory cell infiltrations along the alveolar walls, as well as pericystic emphysema. Thin-walled or bizarre cysts demonstrated a tendency to coalesce with surrounding cysts via their cystic wall destruction. Fourteen (52%) patients showed improvement and nine (33%) showed progressing disease. More than half of patients with pulmonary PLCH show improvement at follow-up CT. Even thin-walled cysts harbour active inflammatory cells on histopathology and exhibit improvement at follow-up CT. (orig.)

  14. Glycosylation of type II collagen is of major importance for T cell tolerance and pathology in collagen-induced arthritis

    DEFF Research Database (Denmark)

    Bäcklund, Johan; Treschow, Alexandra; Bockermann, Robert;

    2002-01-01

    Type II collagen (CII) is a candidate cartilage-specific autoantigen, which can become post-translationally modified by hydroxylation and glycosylation. T cell recognition of CII is essential for the development of murine collagen-induced arthritis (CIA) and also occurs in rheumatoid arthritis (RA...

  15. Pulmonary langerhans cell histiocytosis in adults: high-resolution CT - pathology comparisons and evolutional changes at CT

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hyo Jin; Lee, Ho Yun; Kim, Tae Sung [Sungkyunkwan University School of Medicine, Department of Radiology and Center for Imaging Science, Samsung Medical Center, Seoul (Korea, Republic of); Lee, Kyung Soo [Sungkyunkwan University School of Medicine, Department of Radiology and Center for Imaging Science, Samsung Medical Center, Seoul (Korea, Republic of); Samsung Medical Center, Department of Radiology, Seoul (Korea, Republic of); Johkoh, Takeshi [Kinki Central Hospital of Mutual Aid Association of Public School Teachers, Department of Radiology, Hyoko (Japan); Tomiyama, Noriyuki [Osaka University Graduate School of Medicine, Department of Radiology, Osaka (Japan); Han, Joungho [Sungkyunkwan University School of Medicine, Department of Pathology, Samsung Medical Center, Seoul (Korea, Republic of)

    2011-07-15

    To compare high-resolution (HR) CT and histopathological findings and to evaluate serial CT findings in pulmonary Langerhans cell histiocytosis (PLCH). We reviewed CT of lung lesions in 27 adults (M:F = 20:7, mean age, 41 {+-} 12.3 years) with PLCH. After evaluating lung abnormalities including nodules, micronodules, thick-walled, thin-walled, and bizarre-shaped cysts and reticulation, observers compared CT findings obtained at lung biopsy sites with histopathological findings. The final CT was compared with the initial CT to determine disease extent changes. The most frequently observed patterns of lung abnormalities were micronodules (n = 24, 89%), thick-walled (n = 22, 82%), and thin-walled (n = 22, 82%) cysts. Even thin-walled and bizarre cysts harboured active inflammatory Langerhans cell sheets and eosinophils in their walls. In thin-walled cysts, we noted pericystic inflammatory cell infiltrations along the alveolar walls, as well as pericystic emphysema. Thin-walled or bizarre cysts demonstrated a tendency to coalesce with surrounding cysts via their cystic wall destruction. Fourteen (52%) patients showed improvement and nine (33%) showed progressing disease. More than half of patients with pulmonary PLCH show improvement at follow-up CT. Even thin-walled cysts harbour active inflammatory cells on histopathology and exhibit improvement at follow-up CT. (orig.)

  16. [Systemic immunological response in children with chronic gingivitis and gastro-intestinal pathology].

    Science.gov (United States)

    Romanenko, E G

    2014-01-01

    Study of the immune system mechanisms in chronic catarrhal gingivitis in children with gastrointestinal pathology was performed in 102 children (49 with chronic gastritis and duodenitis and 53 with no signs of gastrointestinal pathology). Forty-eight children with healthy periodontium constituted control group. Generalized chronic catarrhal gingivitis in children with gastroduodenal pathology is characterized by intense humoral response by simultaneous T-cell immunity suppression. Detection of high serum titers of circulating immune complexes in patients with chronic catarrhal gingivitis suggests a role of immune response in the pathogenesis of periodontal disease increases with concomitant diseases of the upper gastrointestinal tract.

  17. Renal clear cell carcinoma metastasis to salivary glands - a series of 9 cases: clinico-pathological study.

    Science.gov (United States)

    Majewska, H; Skálová, A; Radecka, K; Stodulski, D; Hyrcza, M; Stankiewicz, C; Biernat, W

    2016-03-01

    Metastatic tumors involving salivary glands arising from the non-head and neck area are very rare. Renal cell carcinoma (RCC) is known for its high propensity for metastasis to unusual localizations. RCC metastasis to the maxillofacial area is an uncommon event (16%), but metastasis to salivary glands is extremely rare. We report a series of 9 such cases retrieved from two institutions. The group included 6 females and 3 males. The age at diagnosis ranged from 60 to 97 years (mean 72.6 years). The tumors involved the parotid gland in 7 cases, and the submandibular and small salivary gland of the oral cavity in 1 case each. The size of tumors ranged from 0.4 to 5 cm. Total parotidectomy with selective neck dissection was performed in 4 cases, while superficial parotidectomy was performed in 1 case and simple resection in 3 cases. Histologically, all the tumors were clear cell renal cell carcinomas, and therefore the differential diagnosis mainly included clear cell variants of salivary gland carcinomas. The parotid gland was the initial manifestation of renal malignancy in 4 of the cases, while in the remaining 5 cases a history of RCC had been known. The salivary gland involvement developed from 11 months to 13 years after the time of diagnosis of the primary tumor. In 2 cases it was the first site of dissemination. Pathologists need to maintain a high index of suspicion for the possibility of metastasis when confronted with oncocytic or clear cell neoplasms developing in salivary glands. RCC, although rare, should be included in this differential diagnosis. PMID:27179273

  18. Synergistically increased ILC2 and Th9 cells in lung tissue jointly promote the pathological process of asthma in mice.

    Science.gov (United States)

    Ying, Xinyu; Su, Zhaoliang; Bie, Qingli; Zhang, Pan; Yang, Huijian; Wu, Yumin; Xu, Yunyun; Wu, Jing; Zhang, Mengying; Wang, Shengjun; Xu, Huaxi

    2016-06-01

    In recent years, T helper (Th) 9 cells have been demonstrated to be key mediators in immune responses in asthmatic lungs, and innate lymphoid cells 2 (ILC2s) have been described as a novel type of innate immunocyte with the ability to enhance immunoglobulin E (IgE) production. However, the interaction between ILC2s and Th9 cells in the pulmonary system of a mouse model of asthma remains to be elucidated. In the present study, the response state of lung tissue with regards to Th9 and ILC2s in a mouse model of asthma was investigated by detecting Th9‑ and ILC2‑associated cytokine receptors. The present study also investigated the association between the expression levels of the cytokine receptors in lung tissue samples and the IgE levels in sera samples from mouse models of asthma. Results from the present study demonstrated that the frequency of ILC2s and Th9 cells was significantly increased in the lung tissue samples, indicating that a Th2-type immune response had occurred. In addition, high mRNA expression levels of RAR‑related orphan receptor α, interleukin 1 receptor‑like 1, transcription factor PU.1 and interleukin (IL)‑9 were observed. Furthermore, IL‑5Rα, IL‑13Rα2 and high‑affinity IgE receptor were increased in mouse models of asthma, and a positive association was observed between the expression levels of ILC2‑ or Th9‑associated receptors in tissue samples and IgE levels in the sera. This indicated that ILC2s and Th9 were in a state of polarization and may promote each other in the lung tissue of mouse models of asthma, and that the lung tissue was responding to the two types of cells via increased expression of receptors. PMID:27109139

  19. A kinetic mechanism for cell sorting based on local variations in cell motility

    Science.gov (United States)

    Strandkvist, Charlotte; Juul, Jeppe; Baum, Buzz; Kabla, Alexandre J.; Duke, Tom

    2014-01-01

    Our current understanding of cell sorting relies on physical difference, either in the interfacial properties or motile force, between cell types. But is such asymmetry a prerequisite for cell sorting? We test this using a minimal model in which the two cell populations are identical with respect to their physical properties and differences in motility arise solely from how cells interact with their surroundings. The model resembles the Schelling model used in social sciences to study segregation phenomena at the scale of societies. Our results demonstrate that segregation can emerge solely from cell motility being a dynamic property that changes in response to the local environment of the cell, but that additional mechanisms are necessary to reproduce the envelopment behaviour observed in vitro. The time course of segregation follows a power law, in agreement with the scaling reported from experiment and in other models of motility-driven segregation. PMID:25485079

  20. Probing mechanical principles of cell-nanomaterial interactions

    Science.gov (United States)

    Gao, Huajian

    2014-01-01

    With the rapid development of nanotechnology, various types of nanoparticles, nanowires, nanofibers, nanotubes, and atomically thin plates and sheets have emerged as candidates for an ever increasing list of potential applications for next generation electronics, microchips, composites, barrier coatings, biosensors, drug delivery, and energy harvesting and conversion systems. There is now an urgent societal need to understand both beneficial and hazardous effects of nanotechnology which is projected to produce and release thousands of tons of nanomaterials into the environment in the coming decades. This paper aims to present an overview of some recent studies conducted at Brown University on the mechanics of cell-nanomaterial interactions, including the modeling of nanoparticles entering cells by receptor-mediated endocytosis and coarse-grained molecular dynamics simulations of nanoparticles interacting with cell membranes. The discussions will be organized around the following questions: Why and how does cellular uptake of nanoparticles depend on particle size, shape, elasticity and surface structure? In particular, we will discuss the effect of nanoparticle size on receptor-mediated endocytosis, the effect of elastic stiffness on cell-particle interactions, how high aspect ratio nanomaterials such as carbon nanotubes and graphenes enter cells and how different geometrical patterns of ligands on a nanoparticle can be designed to control the rate of particle uptake.

  1. Probing mechanical properties of living cells by magnetopneumography.

    Science.gov (United States)

    Möller, W; Takenaka, S; Rust, M; Stahlhofen, W; Heyder, J

    1997-01-01

    Magnetopneumography (MPG) has been used to study long-term particle clearance from human lungs as well as cellular motility of pulmonary macrophages (PMs). This study describes an extension of the method enabling the measurement of mechanical properties of PM cells in vivo. Ferromagnetic microparticles are inhaled and then retained in the alveolar region of the lungs, where they are phagocytized within hours by PMs. The magnetic particles can be rotated in weak magnetic fields, and the response to this twisting shear (force) is detected as a macroscopic magnetic field producing a measure of cytoskeletal mechanics. Cytoplasmic viscosity is very high compared with that of water and is strongly non-Newtonian. Under rotational stresses from 0.4 to 6.4 Pa, it acts like a pseudoplastic fluid showing a characteristic shear rate dependence. The viscosity as well as the stiffness of the cytoskeleton increases with increasing shear stress as seems typical for living tissue and evidence for an intact cytoskeletal matrix. The particle recoil as measured by the amount of recoverable strain following a short twisting force describes a cytoplasmic elasticity that depends on both level and duration of stress. These investigations on the mechanical properties of living human cells are promising and should lead to better understanding of cellular dysfunction in disease as well as pathways for drug administration. PMID:10174196

  2. The mechanism of gene targeting in human somatic cells.

    Directory of Open Access Journals (Sweden)

    Yinan Kan

    2014-04-01

    Full Text Available Gene targeting in human somatic cells is of importance because it can be used to either delineate the loss-of-function phenotype of a gene or correct a mutated gene back to wild-type. Both of these outcomes require a form of DNA double-strand break (DSB repair known as homologous recombination (HR. The mechanism of HR leading to gene targeting, however, is not well understood in human cells. Here, we demonstrate that a two-end, ends-out HR intermediate is valid for human gene targeting. Furthermore, the resolution step of this intermediate occurs via the classic DSB repair model of HR while synthesis-dependent strand annealing and Holliday Junction dissolution are, at best, minor pathways. Moreover, and in contrast to other systems, the positions of Holliday Junction resolution are evenly distributed along the homology arms of the targeting vector. Most unexpectedly, we demonstrate that when a meganuclease is used to introduce a chromosomal DSB to augment gene targeting, the mechanism of gene targeting is inverted to an ends-in process. Finally, we demonstrate that the anti-recombination activity of mismatch repair is a significant impediment to gene targeting. These observations significantly advance our understanding of HR and gene targeting in human cells.

  3. Metastatic non-small-cell lung cancer: consensus on pathology and molecular tests, first-line, second-line, and third-line therapy: 1st ESMO Consensus Conference in Lung Cancer; Lugano 2010

    DEFF Research Database (Denmark)

    Felip, E; Gridelli, C; Baas, P;

    2011-01-01

    the conference, the expert panel prepared clinically relevant questions concerning five areas: early and locally advanced non-small-cell lung cancer (NSCLC), first-line metastatic NSCLC, second-/third-line NSCLC, NSCLC pathology and molecular testing, and small-cell lung cancer to be addressed through discussion......The 1st ESMO Consensus Conference on lung cancer was held in Lugano, Switzerland on 21 and 22 May 2010 with the participation of a multidisciplinary panel of leading professionals in pathology and molecular diagnostics, medical oncology, surgical oncology and radiation oncology. Before...

  4. Enterocolitis induced by autoimmune targeting of enteric glial cells: A possible mechanism in Crohn's disease?

    Science.gov (United States)

    Cornet, Anne; Savidge, Tor C.; Cabarrocas, Julie; Deng, Wen-Lin; Colombel, Jean-Frederic; Lassmann, Hans; Desreumaux, Pierre; Liblau, Roland S.

    2001-11-01

    Early pathological manifestations of Crohn's disease (CD) include vascular disruption, T cell infiltration of nerve plexi, neuronal degeneration, and induction of T helper 1 cytokine responses. This study demonstrates that disruption of the enteric glial cell network in CD patients represents another early pathological feature that may be modeled after CD8+ T cell-mediated autoimmune targeting of enteric glia in double transgenic mice. Mice expressing a viral neoself antigen in astrocytes and enteric glia were crossed with specific T cell receptor transgenic mice, resulting in apoptotic depletion of enteric glia to levels comparable in CD patients. Intestinal and mesenteric T cell infiltration, vasculitis, T helper 1 cytokine production, and fulminant bowel inflammation were characteristic hallmarks of disease progression. Immune-mediated damage to enteric glia therefore may participate in the initiation and/or the progression of human inflammatory bowel disease.

  5. Pathological Plasticity in Fragile X Syndrome

    Directory of Open Access Journals (Sweden)

    Brandon S. Martin

    2012-01-01

    Full Text Available Deficits in neuronal plasticity are common hallmarks of many neurodevelopmental disorders. In the case of fragile-X syndrome (FXS, disruption in the function of a single gene, FMR1, results in a variety of neurological consequences directly related to problems with the development, maintenance, and capacity of plastic neuronal networks. In this paper, we discuss current research illustrating the mechanisms underlying plasticity deficits in FXS. These processes include synaptic, cell intrinsic, and homeostatic mechanisms both dependent on and independent of abnormal metabotropic glutamate receptor transmission. We place particular emphasis on how identified deficits may play a role in developmental critical periods to produce neuronal networks with permanently decreased capacity to dynamically respond to changes in activity central to learning, memory, and cognition in patients with FXS. Characterizing early developmental deficits in plasticity is fundamental to develop therapies that not only treat symptoms but also minimize the developmental pathology of the disease.

  6. Analyses of CD20 Monoclonal Antibody–Mediated Tumor Cell Killing Mechanisms: Rational Design of Dosing Strategies

    Science.gov (United States)

    Lindorfer, Margaret A.

    2014-01-01

    Since approval of rituximab for treatment of B cell non-Hodgkin lymphoma, development of monoclonal antibodies (mAbs) for cancer treatment and elucidation of their cytotoxic mechanisms have been subject to intense investigations. Compelling evidence indicates that rituximab and another CD20 mAb, ofatumumab, must use the body’s cellular and humoral immune effector functions to kill malignant cells. Other U.S. Food and Drug Administration–approved mAbs, including obinutuzumab, cetuximab, and trastuzumab, require, in part, these effector mechanisms to eliminate tumor cells. Although gram quantities of mAbs can be administered to patients, our investigations of CD20 mAb-based therapies for chronic lymphocytic leukemia (CLL), including correlative measurements in clinical trials and studies with primary cells and cell lines, indicate that effector mechanisms necessary for mAb activity can be saturated or exhausted if tumor burdens are high, thus substantially compromising the efficacy of high-dose mAb therapy. Under these conditions, another reaction (trogocytosis) predominates in which bound CD20 mAb and CD20 are removed from targeted cells by effector cells that express Fcγ receptors, thereby allowing malignant cells to escape unharmed and continue to promote disease pathology. To address this problem, we propose that a low-dose strategy, based on administering 30–50 mg of CD20 mAb three times per week, may be far more effective for CLL than standard dosing because it will minimize effector function saturation and reduce trogocytosis. This approach may have general applicability to other mAbs that use immune effector functions, and could be formulated into a subcutaneous treatment strategy that would be more accessible and possibly more efficacious for patients. PMID:24944188

  7. Genetic aberrations in small B-cell lymphomas and leukemias: molecular pathology, clinical relevance and therapeutic targets.

    Science.gov (United States)

    Bogusz, Agata M; Bagg, Adam

    2016-09-01

    Small B-cell lymphomas and leukemias (SBCLs) are a clinically, morphologically, immunophenotypically and genetically heterogeneous group of clonal lymphoid neoplasms, including entities such as chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL), mantle cell lymphoma (MCL), follicular lymphoma (FL), lymphoplasmacytic lymphoma (LPL), marginal zone lymphoma (MZL) and hairy cell leukemia (HCL). The pathogenesis of some of these lymphoid malignancies is characterized by distinct translocations, for example t(11;14) in the majority of cases of MCL and t(14;18) in most cases of FL, whereas other entities are associated with a variety of recurrent but nonspecific numeric chromosomal abnormalities, as exemplified by del(13q14), del(11q22), and +12 in CLL, and yet others such as LPL and HCL that lack recurrent or specific cytogenetic aberrations. The recent surge in next generation sequencing (NGS) technology has shed more light on the genetic landscape of SBCLs through characterization of numerous driver mutations including SF3B1 and NOTCH1 in CLL, ATM and CCND1 in MCL, KMT2D and EPHA7 in FL, MYD88 (L265P) in LPL, KLF2 and NOTCH2 in splenic MZL (SMZL) and BRAF (V600E) in HCL. The identification of distinct genetic lesions not only provides greater insight into the molecular pathogenesis of these disorders but also identifies potential valuable biomarkers for prognostic stratification, as well as specific targets for directed therapy. This review discusses the well-established and recently identified molecular lesions underlying the pathogenesis of SBCLs, highlights their clinical relevance and summarizes novel targeted therapies. PMID:27121112

  8. Proteome-wide analysis of SUMO2 targets in response to pathological DNA replication stress in human cells

    DEFF Research Database (Denmark)

    Bursomanno, Sara; Beli, Petra; Khan, Asif M;

    2015-01-01

    subfamily. SUMO2/3, in contrast to SUMO1, are predominantly involved in the cellular response to certain stresses, including heat shock. Substantial evidence from studies in yeast has shown that SUMOylation plays an important role in the regulation of DNA replication and repair. Here, we report a proteomic...... analysis of proteins modified by SUMO2 in response to DNA replication stress in S phase in human cells. We have identified a panel of 22 SUMO2 targets with increased SUMOylation during DNA replication stress, many of which play key functions within the DNA replication machinery and/or in the cellular...

  9. Xenotransplantation of microencaps bovine chromaffin cells into hemiparkinsonian monkeys:a analyses of behaviour,biochemistry and pathology

    Institute of Scientific and Technical Information of China (English)

    XUE Y. L.; WANG L. N.; WANG Z. F.; ZHONG D. G.; LI X. J.; CUI X.; MA X. J.; ZHU Ming-wei; SUN A. M.

    2001-01-01

    @@ This study examines the effects of xenografts of microencapsulated bovine chromaffin cells (BCCs) on the rotational behavior of hemiparkinsonian monkey recipients. In addition, it determines the content of monoamine neurotransmitters and their major metabolites in the neostriatum in hemiparkinsonian monkeys. The hemiparkinsonian model in monkeys was induced by a unilateral intracarotid injection of methyl-phenyl-tetrahydropyridine (MPTP). Unencapsulated BCCs (n = 2), BCCs microencapsulated (n= 6) in alginate-polylysine-alginate (APA) membranes as well as empty microencapsules (n = 1) were grafted into the neostriatum of the hemiparkinsonian monkeys.

  10. Regulatory mechanism of radiation-induced cancer cell death by the change of cell cycle

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Soo Jin; Jeong, Min Ho; Jang, Ji Yeon [College of Medicine, Donga Univ., Pusan (Korea, Republic of)

    2003-09-01

    cycle regulatory activites. In this study, we present a unique and reproducible model in which for investigating the mechanisms of various, radiation-induced, cancer cell death patterns. Further evaluation by using this model will provide a potent target for a new strategy of radiotherapy.

  11. Time-dependent Mechanisms in Beta-cell Glucose Sensing

    OpenAIRE

    Vagn Korsgaard, Thomas; Colding-Jørgensen, Morten

    2006-01-01

    The relation between plasma glucose and insulin release from pancreatic beta-cells is not stationary in the sense that a given glucose concentration leads to a specific rate of insulin secretion. A number of time-dependent mechanisms appear to exist that modify insulin release both on a short and a longer time scale. Typically, two phases are described. The first phase, lasting up to 10 min, is a pulse of insulin release in response to fast changes in glucose concentration. The second phase i...

  12. Mitochondrial and Cell Death Mechanisms in Neurodegenerative Diseases

    Directory of Open Access Journals (Sweden)

    Lee J. Martin

    2010-03-01

    Full Text Available Alzheimer’s disease (AD, Parkinson’s disease (PD and amyotrophic lateral sclerosis (ALS are the most common human adult-onset neurodegenerative diseases. They are characterized by prominent age-related neurodegeneration in selectively vulnerable neural systems. Some forms of AD, PD, and ALS are inherited, and genes causing these diseases have been identified. Nevertheless, the mechanisms of the neuronal cell death are unresolved. Morphological, biochemical, genetic, as well as cell and animal model studies reveal that mitochondria could have roles in this neurodegeneration. The functions and properties of mitochondria might render subsets of selectively vulnerable neurons intrinsically susceptible to cellular aging and stress and overlying genetic variations, triggering neurodegeneration according to a cell death matrix theory. In AD, alterations in enzymes involved in oxidative phosphorylation, oxidative damage, and mitochondrial binding of Aβ and amyloid precursor protein have been reported. In PD, mutations in putative mitochondrial proteins have been identified and mitochondrial DNA mutations have been found in neurons in the substantia nigra. In ALS, changes occur in mitochondrial respiratory chain enzymes and mitochondrial cell death proteins. Transgenic mouse models of human neurodegenerative disease are beginning to reveal possible principles governing the biology of selective neuronal vulnerability that implicate mitochondria and the mitochondrial permeability transition pore. This review summarizes how mitochondrial pathobiology might contribute to neuronal death in AD, PD, and ALS and could serve as a target for drug therapy.

  13. Mechanism study of electrochemical oxidation in the terylene diaphragm cell

    Institute of Scientific and Technical Information of China (English)

    YU Xiu-juan; WANG Hui; SUN De-zhi; SONG Lai-wen; WU Lan

    2006-01-01

    By using a self-made carbon/polytetrafluoroethylene (C/PTFE) O2-fed as cathode and Ti/IrO2/RuO2 as anode, the effects of electrochemical oxidation of phenol and the coal-gas wastewater containing phenol were studied. The terylene diaphragm which kept pH>12 in cathodic compartment and pH<1 in the anodic compartment was selected in the experiment in comparison with the other ctron spin resonance spectrum(ESR) and the fluorescence spectra. Compared with pH, the accumulated H2O2 and the COD removal of the no-diaphragm cell, the mechanism of electrochemical oxidation in the terylene diaphragm cell was supposed. The degradation of by oxygen reduction at the cathode. The mineralization of phenol in the diaphragm cell was better than that in the no-diaphragm cell.When the coal-gas wastewater was treated by the electrolysis system with terylene diaphragm, the average removal efficiency of the volatile phenol and COD were 100% and 79.6%, respectively.

  14. Mechanism of multidrug resistance of human small cell lung cancer cell line H446/VP

    Institute of Scientific and Technical Information of China (English)

    WANG Yan-ling; YAN Yun-li; ZHOU Na-jing; HAN Shuo; ZHAO Jun-xia; CAO Cui-li; Lü Yu-hong

    2010-01-01

    Background Small cell lung cancer (SCLC) is the most aggressive form of lung cancer. This study aimed to investigate the mechanism of human small cell lung cancer cell line resistance to etoposide (VP-16), H446/VP.Methods The cell viability was measured by M∏ assay. Immunocytochemistry, reverse transcription-polymerase chain reaction (RT-PCR) and Western blotting methods were used to detect the multidrug resistance gene (MDR1), bcl-2, bax and the topoisomerase Ⅱ (Topo Ⅱ) expressions in H446 and H446/VP cells after treated with or without VP-16.Results The 50% inhibition concentration (IC50) of VP-16 on H446 cells was 49 mg/L, and 836 mg/L was for H446/VP cells. The expressions of MDR1 and bcl-2 were up-regulated, while the amounts of bax and Topo Ⅱ were reduced in H446/VP cells. After treated with 49 mg/L of VP-16, it showed that the drug could significantly inhibit bcl-2 and Topo Ⅱ expressions, and increase bax expression in H446 cells compared with that of H446/VP cells.Conclusions The H446/VP cell was stably resistant to VP-16. The decreased expression of Topo Ⅱ was correlated with the H446/VP multidrug resistance. The elevated expressions of MDR1, and the altered apoptotic pathways also played an important role in VP-16 induced multidrug resistance of SCLC.

  15. Molecular Mechanisms of Microcystin Toxicity in Animal Cells

    Directory of Open Access Journals (Sweden)

    Alexandre Campos

    2010-01-01

    Full Text Available Microcystins (MC are potent hepatotoxins produced by the cyanobacteria of the genera Planktothrix, Microcystis, Aphanizomenon, Nostoc and Anabaena. These cyclic heptapeptides have strong affinity to serine/threonine protein phosphatases (PPs thereby acting as an inhibitor of this group of enzymes. Through this interaction a cascade of events responsible for the MC cytotoxic and genotoxic effects in animal cells may take place. Moreover MC induces oxidative stress in animal cells and together with the inhibition of PPs, this pathway is considered to be one of the main mechanisms of MC toxicity. In recent years new insights on the key enzymes involved in the signal-transduction and toxicity have been reported demonstrating the complexity of the interaction of these toxins with animal cells. Key proteins involved in MC up-take, biotransformation and excretion have been identified, demonstrating the ability of aquatic animals to metabolize and excrete the toxin. MC have shown to interact with the mitochondria. The consequences are the dysfunction of the organelle, induction of reactive oxygen species (ROS and cell apoptosis. MC activity leads to the differential expression/activity of transcriptional factors and protein kinases involved in the pathways of cellular differentiation, proliferation and tumor promotion activity. This activity may result from the direct inhibition of the protein phosphatases PP1 and PP2A. This review aims to summarize the increasing data regarding the molecular mechanisms of MC toxicity in animal systems, reporting for direct MC interacting proteins and key enzymes in the process of toxicity biotransformation/excretion of these cyclic peptides.

  16. Novel CD47: SIRPα dependent mechanism for the activation of STAT3 in antigen-presenting cell.

    Directory of Open Access Journals (Sweden)

    Natan Toledano

    Full Text Available Cell surface CD47 interacts with its receptor, signal-regulatory-protein α (SIRPα that is expressed predominantly on macrophages, to inhibit phagocytosis of normal, healthy cells. This "don't eat me" signal is mediated through tyrosine phosphorylation of SIRPα at the cytoplasmic ITIM motifs and the recruitment of the phosphatase, SHP-1. We previously revealed a novel mechanism for the activation of the STAT3 pathway and the regulation of human APC maturation and function that is based on cell:cell interaction. In this study, we present evidence supporting the notion that CD47:SIRPα serves as a cell surface receptor: ligand pair involved in this contact-dependent STAT3 activation and regulation of APC maturation. We show that upon co-culturing APC with various primary and tumor cell lines STAT3 phosphorylation and IL-10 expression are induced, and such regulation could be suppressed by specific CD47 siRNAs and shRNAs. Significantly, >50% reduction in CD47 expression abolished the contact-dependent inhibition of T cell activation. Furthermore, co-immunoprecipitation experiments revealed a physical association between SIRPα and STAT3. Thus, we suggest that in addition to signaling through the ITIM-SHP-1 complex that transmit an anti-phagocytotic, CD47:SIRPα also triggers STAT3 signaling that is linked to an immature APC phenotype and peripheral tolerance under steady state and pathological conditions.

  17. Multifocal Langerhans cell histiocytosis in an adult with a pathological fracture of the mandible and spontaneous malunion: A case report

    Science.gov (United States)

    SHI, SAILANG; LIU, YANMING; FU, TAO; LI, XIUZHEN; ZHAO, SHIFANG

    2014-01-01

    Langerhans cell histiocytosis (LCH) is rare in the adult population and even rarer with jaw involvement. The current study presents the case of a 39-year-old male who complained of recurrent pain, swelling of the gingiva and an occasional pus-like discharge in the right mandible for one year. The patient was previously prescribed antibiotics, but this did not resolve the problem. An initial panoramic radiograph showed an osteolytic lesion and bone fracture in the right mandible. Eight months later, a new radiograph showed the spontaneous malunion of the fractured mandible. The patient was eventually diagnosed with Langerhans cell histiocytosis by histopathology and immunohistochemistry. Further lesions were found in the ribs and ilium by nuclear bone scanning. The patient was subsequently treated with systemic chemotherapy, and the lesions are currently effectively being controlled. This study is the first to show that spontaneous intralesional bone regeneration may lead to reunification of the mandible fracture caused by LCH in an adult. PMID:25120660

  18. Residual lymph node status is an independent prognostic factor in esophageal squamous cell Carcinoma with pathologic T0 after preoperative radiotherapy

    International Nuclear Information System (INIS)

    To evaluate the prognostic factors affecting survival in esophageal squamous cell Carcinoma (ESCC) patients with pathologic T0 (ypT0) underwent preoperative radiotherapy. Two hundred and ninety-six patients with ESCC who had received preoperative radiotherapy from 1980 to 2007 were retrospectively analyzed. One hundred patients were ypT0 after preoperative radiotherapy. Univariate and multivariate analyses were performed to evaluate the predictive impact of residual lymph node status on overall survival (OS) and progression-free survival (PFS). Among the originally analyzed 296 patients, 100 (33.7 %) patients had ypT0, including 78 patients (78 %) with ypT0N0, and 22 patients (22 %) with ypT0N1. The 5-year OS of the total patients was 42.4 %. Patients with ypT0N0 have significant improved 5-year OS and PFS than ypT0N1 patients (OS: 50.7 % vs 13.6 %, P = 0.004; PFS: 49.6 % vs 13.6 %, P = 0.003). In multivariate analysis, residual lymph node status was also an independent prognostic factors for OS (HR: 0.406, 95 % CI: 0.240–0.686, P = 0.001) and PFS (HR: 0.427, 95 % CI: 0.248–0.734, P = 0.002). Our results indicate that patients with ypT0N0 after preoperative radiotherapy had significantly better OS and PFS than patients with ypT0N1 in ESCC. Residual nodal metastasis of ESCC patients with pathological complete response of the primary tumor after neoadjuvant radiotherapy does influence prognosis

  19. Functional role of regulatory T cells in B cell lymphoma and related mechanisms.

    Science.gov (United States)

    Wu, Wei; Wan, Jun; Xia, Ruixiang; Huang, Zhenqi; Ni, Jing; Yang, Mingzhen

    2015-01-01

    B cell lymphoma (BCL) has a higher degree of malignancy and complicated pathogenic mechanism. Regulatory T cells (Treg cells) are known to exert certain immune suppression functions, in addition to immune mediating effects. Recent studies have revealed the role of Treg cells in pathogenesis and progression of multiple malignant tumors. This study therefore investigated the functional role and related mechanism of Treg cells in BCL. A cohort of thirty patients who were diagnosed with BCL in our hospital between January 2013 and December 2014. Another thirty healthy individuals were recruited. Peripheral blood mononuclear cells (PBMCs) were separated and analyzed for the ratio of CD4+/CD25+ Treg cells. The mRNA expression levels of Foxp3, transforming growth factor (TGF)-β1 and interleukin (IL)-10 genes were quantified by real-time PCR, while their serum levels were determined by enzyme-linked immunosorbent assay (ELISA). Meanwhile all laboratory indexes for patients were monitored during the complete remission (CR) stage. BCL patients significantly elevated ratio of CD4+/CD25+ Treg cells, which were decreased at CR stage. mRNA levels of Foxp3, TGF-β1 and IL-10, in addition to protein levels of TGF-β1 and IL-10 were potentiated in lymphoma patients but decreased in CR patients (Pregulating cytokines, thereby facilitating the pathogenesis and progression of lymphoma. PMID:26464657

  20. Illumination from light-emitting diodes (LEDs) disrupts pathological cytokines expression and activates relevant signal pathways in primary human retinal pigment epithelial cells.

    Science.gov (United States)

    Shen, Ye; Xie, Chen; Gu, Yangshun; Li, Xiuyi; Tong, Jianping

    2016-04-01

    Age-related macular degeneration (AMD) is the leading cause of blindness in the aged people. The latest systemic review of epidemiological investigations revealed that excessive light exposure increases the risk of AMD. With the drastically increasing use of high-energy light-emitting diodes (LEDs) light in our domestic environment nowadays, it is supposed to pose a potential oxidative threat to ocular health. Retinal pigment epithelium (RPE) is the major ocular source of pathological cytokines, which regulate local inflammation and angiogenesis. We hypothesized that high-energy LED light might disrupt the pathological cytokine expression of retinal pigment epithelium (RPE), contributing to the pathogenesis of AMD. Primary human RPE cells were isolated from eyecups of normal eye donors and seeded into plate wells for growing to confluence. Two widely used multichromatic white light-emitting diodes (LEDs) with correlated color temperatures (CCTs) of 2954 and 7378 K were used in this experiment. The confluent primary RPE cells were under white LEDs light exposure until 24 h. VEGF-A, IL-6, IL-8 and MCP-1 proteins and mRNAs were measured using an ELISA kit and RT-PCR, respectively. Activation of mitogen-activated protein kinases (MAPKs), Akt, Janus kinase (JAK)2 and Nuclear factor (NF)-κB signal pathways after LEDs illumination were evaluated by western blotting analysis. The level of reactive oxygen species (ROS) using chloromethyl- 2',7'-dichlorodihydrofluorescein diacetate. Inhibitors of relevant signal pathways and anti-oxidants were added to the primary RPE cells before LEDs illumination to evaluate their biological functions. We found that 7378 K light, but not 2954 K upregulated the VEGF-A, IL-6, IL-8 and downregulated MCP-1 proteins and mRNAs levels in a time-dependent manner. In parallel, initial activation of MAPKs and NF-κB signal pathways were also observed after 7378 K light exposure. Mechanistically, antioxidants for eliminating reactive oxygen

  1. Illumination from light-emitting diodes (LEDs) disrupts pathological cytokines expression and activates relevant signal pathways in primary human retinal pigment epithelial cells.

    Science.gov (United States)

    Shen, Ye; Xie, Chen; Gu, Yangshun; Li, Xiuyi; Tong, Jianping

    2016-04-01

    Age-related macular degeneration (AMD) is the leading cause of blindness in the aged people. The latest systemic review of epidemiological investigations revealed that excessive light exposure increases the risk of AMD. With the drastically increasing use of high-energy light-emitting diodes (LEDs) light in our domestic environment nowadays, it is supposed to pose a potential oxidative threat to ocular health. Retinal pigment epithelium (RPE) is the major ocular source of pathological cytokines, which regulate local inflammation and angiogenesis. We hypothesized that high-energy LED light might disrupt the pathological cytokine expression of retinal pigment epithelium (RPE), contributing to the pathogenesis of AMD. Primary human RPE cells were isolated from eyecups of normal eye donors and seeded into plate wells for growing to confluence. Two widely used multichromatic white light-emitting diodes (LEDs) with correlated color temperatures (CCTs) of 2954 and 7378 K were used in this experiment. The confluent primary RPE cells were under white LEDs light exposure until 24 h. VEGF-A, IL-6, IL-8 and MCP-1 proteins and mRNAs were measured using an ELISA kit and RT-PCR, respectively. Activation of mitogen-activated protein kinases (MAPKs), Akt, Janus kinase (JAK)2 and Nuclear factor (NF)-κB signal pathways after LEDs illumination were evaluated by western blotting analysis. The level of reactive oxygen species (ROS) using chloromethyl- 2',7'-dichlorodihydrofluorescein diacetate. Inhibitors of relevant signal pathways and anti-oxidants were added to the primary RPE cells before LEDs illumination to evaluate their biological functions. We found that 7378 K light, but not 2954 K upregulated the VEGF-A, IL-6, IL-8 and downregulated MCP-1 proteins and mRNAs levels in a time-dependent manner. In parallel, initial activation of MAPKs and NF-κB signal pathways were also observed after 7378 K light exposure. Mechanistically, antioxidants for eliminating reactive oxygen

  2. The cell-stretcher: A novel device for the mechanical stimulation of cell populations

    Science.gov (United States)

    Seriani, S.; Del Favero, G.; Mahaffey, J.; Marko, D.; Gallina, P.; Long, C. S.; Mestroni, L.; Sbaizero, O.

    2016-08-01

    Mechanical stimulation appears to be a critical modulator for many aspects of biology, both of living tissue and cells. The cell-stretcher, a novel device for the mechanical uniaxial stimulation of populations of cells, is described. The system is based on a variable stroke cam-lever-tappet mechanism which allows the delivery of cyclic stimuli with frequencies of up to 10 Hz and deformation between 1% and 20%. The kinematics is presented and a simulation of the dynamics of the system is shown, in order to compute the contact forces in the mechanism. The cells, following cultivation and preparation, are plated on an ad hoc polydimethylsiloxane membrane which is then loaded on the clamps of the cell-stretcher via force-adjustable magnetic couplings. In order to show the viability of the experimentation and biocompatibility of the cell-stretcher, a set of two in vitro tests were performed. Human epithelial carcinoma cell line A431 and Adult Mouse Ventricular Fibroblasts (AMVFs) from a dual reporter mouse were subject to 0.5 Hz, 24 h cyclic stretching at 15% strain, and to 48 h stimulation at 0.5 Hz and 15% strain, respectively. Visual analysis was performed on A431, showing definite morphological changes in the form of cellular extroflections in the direction of stimulation compared to an unstimulated control. A cytometric analysis was performed on the AMVF population. Results show a post-stimulation live-dead ratio deviance of less than 6% compared to control, which proves that the environment created by the cell-stretcher is suitable for in vitro experimentation.

  3. An electrical tuning mechanism in turtle cochlear hair cells.

    Science.gov (United States)

    Crawford, A C; Fettiplace, R

    1981-03-01

    through the same micropipette, failed to produce any change in the auditory nerve discharge. The experiment demonstrates that current injection does not produce gross movements of the electrode tip.7. The contribution of the electrical resonance to hair-cell tuning was assessed by dividing the linear tuning curve by the cell's impedance as a function of frequency. The procedure assumes that the electrical resonance is independent of other filtering stages, and on this assumption the resonance can account for the tip of the acoustical tuning curve.8. The residual filter produced by the division was broad; it exhibited a high-frequency roll-off with a corner frequency at 500-600 Hz, similar in all cells, and a low-frequency roll-off, with a corner frequency from 30 to 350 Hz which varied from cell to cell but was uncorrelated with the characteristic frequency of the cell.9. The phase of the receptor potential relative to the sound pressure at the tympanum was measured in ten cells. For low intensities the phase characteristic was independent of the sound pressure. At low frequencies the receptor potential led the sound by 270-360 degrees , and in the region of the characteristic frequency there was an abrupt phase lag of 90-180 degrees ; the abruptness of the phase change depended upon the Q of the cell.10. The calculated phase shift of the electrical resonator as a function of frequency was subtracted from the phase characteristic of the receptor potential. The subtraction removed the sharp phase transition around the characteristic frequency, and in this frequency region the residual phase after subtraction was approximately constant at +180 degrees . This is consistent with the idea that the hair cells depolarize in response to displacements of the basilar membrane towards the scala vestibuli. The high-frequency region of the residual phase characteristic was similar in all cells.11. It is concluded that each hair cell contains its own electrical resonance mechanism

  4. Mechanical fatigue performance of PCL-chondroprogenitor constructs after cell culture under bioreactor mechanical stimulus.

    Science.gov (United States)

    Panadero, Juan Alberto; Sencadas, Vitor; Silva, Sonia C M; Ribeiro, Clarisse; Correia, Vitor; Gama, Francisco M; Gomez Ribelles, José Luis; Lanceros-Mendez, Senentxu

    2016-02-01

    In tissue engineering of cartilage, polymeric scaffolds are implanted in the damaged tissue and subjected to repeated compression loading cycles. The possibility of failure due to mechanical fatigue has not been properly addressed in these scaffolds. Nevertheless, the macroporous scaffold is susceptible to failure after repeated loading-unloading cycles. This is related to inherent discontinuities in the material due to the micropore structure of the macro-pore walls that act as stress concentration points. In this work, chondrogenic precursor cells have been seeded in poly-ε-caprolactone (PCL) scaffolds with fibrin and some were submitted to free swelling culture and others to cyclic loading in a bioreactor. After cell culture, all the samples were analyzed for fatigue behavior under repeated loading-unloading cycles. Moreover, some components of the extracellular matrix (ECM) were identified. No differences were observed between samples undergoing free swelling or bioreactor loading conditions, neither respect to matrix components nor to mechanical performance to fatigue. The ECM did not achieve the desired preponderance of collagen type II over collagen type I which is considered the main characteristic of hyaline cartilage ECM. However, prediction in PCL with ECM constructs was possible up to 600 cycles, an enhanced performance when compared to previous works. PCL after cell culture presents an improved fatigue resistance, despite the fact that the measured elastic modulus at the first cycle was similar to PCL with poly(vinyl alcohol) samples. This finding suggests that fatigue analysis in tissue engineering constructs can provide additional information missed with traditional mechanical measurements.

  5. Possible Roles of Proinflammatory and Chemoattractive Cytokines Produced by Human Fetal Membrane Cells in the Pathology of Adverse Pregnancy Outcomes Associated with Influenza Virus Infection

    Directory of Open Access Journals (Sweden)

    Noboru Uchide

    2012-01-01

    Full Text Available Pregnant women are at an increased risk of influenza-associated adverse outcomes, such as premature delivery, based on data from the latest pandemic with a novel influenza A (H1N1 virus in 2009-2010. It has been suggested that the transplacental transmission of influenza viruses is rarely detected in humans. A series of our study has demonstrated that influenza virus infection induced apoptosis in primary cultured human fetal membrane chorion cells, from which a factor with monocyte differentiation-inducing (MDI activity was secreted. Proinflammatory cytokines, such as interleukin (IL-6, tumor necrosis factor (TNF-α, and interferon (IFN-β, were identified as a member of the MDI factor. Influenza virus infection induced the mRNA expression of not only the proinflammatory cytokines but also chemoattractive cytokines, such as monocyte chemoattractant protein (MCP-1, regulated on activation, normal T-cell expressed and secreted (RANTES, macrophage inflammatory protein (MIP-1β, IL-8, growth-regulated oncogene (GRO-α, GRO-β, epithelial cell-derived neutrophil-activating protein (ENA-78, and interferon inducible protein (IP-10 in cultured chorion cells. These cytokines are postulated to associate with human parturition. This paper, therefore, reviews (1 lessons from pandemic H1N1 2009 in pregnancy, (2 production of proinflammatory and chemoattractive cytokines by human fetal membranes and their functions in gestational tissues, and (3 possible roles of cytokines produced by human fetal membranes in the pathology of adverse pregnancy outcomes associated with influenza virus infection.

  6. Biophysical response of living cells to boron nitride nanoparticles: uptake mechanism and bio-mechanical characterization

    Energy Technology Data Exchange (ETDEWEB)

    Rasel, Md. Alim Iftekhar; Li, Tong; Nguyen, Trung Dung; Singh, Sanjleena [Queensland University of Technology (QUT), School of Chemistry, Physics and Mechanical Engineering (Australia); Zhou, Yinghong; Xiao, Yin [Queensland University of Technology (QUT), Institute of Health and Biomedical Innovation (Australia); Gu, YuanTong, E-mail: yuantong.gu@qut.edu.au [Queensland University of Technology (QUT), School of Chemistry, Physics and Mechanical Engineering (Australia)

    2015-11-15

    Boron nitride nanomaterials have attracted significant interest due to their superior chemical and physical properties. Despite these novel properties, investigation on the interaction between boron nitride nanoparticle (BN NP) and living systems has been limited. In this study, BN NP (100–250 nm) is assessed as a promising biomaterial for medical applications. The toxicity of BN NP is evaluated by assessing the cells behaviours both biologically (MTT assay, ROS detection etc.) and physically (atomic force microscopy). The uptake mechanism of BN NP is studied by analysing the alternations in cellular morphology based on cell imaging techniques. The results demonstrate in vitro cytocompatibility of BN NP with immense potential for use as an effective nanoparticle for various bio-medical applications.

  7. Biophysical response of living cells to boron nitride nanoparticles: uptake mechanism and bio-mechanical characterization

    International Nuclear Information System (INIS)

    Boron nitride nanomaterials have attracted significant interest due to their superior chemical and physical properties. Despite these novel properties, investigation on the interaction between boron nitride nanoparticle (BN NP) and living systems has been limited. In this study, BN NP (100–250 nm) is assessed as a promising biomaterial for medical applications. The toxicity of BN NP is evaluated by assessing the cells behaviours both biologically (MTT assay, ROS detection etc.) and physically (atomic force microscopy). The uptake mechanism of BN NP is studied by analysing the alternations in cellular morphology based on cell imaging techniques. The results demonstrate in vitro cytocompatibility of BN NP with immense potential for use as an effective nanoparticle for various bio-medical applications

  8. Probing the mechanical properties of TNF-α stimulated endothelial cell with atomic force microscopy

    Directory of Open Access Journals (Sweden)

    Sei-Young Lee

    2011-01-01

    Full Text Available Sei-Young Lee1,2, Ana-Maria Zaske3, Tommaso Novellino1,4*, Delia Danila3, Mauro Ferrari1,5*, Jodie Conyers3, Paolo Decuzzi1,6*1Department of Nanomedicine and Biomedical Engineering, The University of Texas Medical School at Houston, Houston, TX, USA; 2Department of Mechanical Engineering, The University of Texas at Austin, Austin, TX, USA; 3CeTIR – Center for Translational Injury Research, The University of Texas Health Science Center at Houston, Houston, TX, USA; 4Department of Biomedical Engineering, Biomedical Campus University of Rome, Italy; 5MD Anderson Cancer Center, Houston, TX, USA; 6BioNEM – Center of Bio-Nanotechnology and Engineering for Medicine, University of Magna Graecia, Catanzaro, Italy; *Currently at Department of Nanomedicine and Biomedical Engineering, The Methodist Hospital Research Institute, Houston, TX, USAAbstract: TNF-α (tumor necrosis factor-α is a potent pro-inflammatory cytokine that regulates the permeability of blood and lymphatic vessels. The plasma concentration of TNF-α is elevated (> 1 pg/mL in several pathologies, including rheumatoid arthritis, atherosclerosis, cancer, pre-eclampsia; in obese individuals; and in trauma patients. To test whether circulating TNF-α could induce similar alterations in different districts along the vascular system, three endothelial cell lines, namely HUVEC, HPMEC, and HCAEC, were characterized in terms of 1 mechanical properties, employing atomic force microscopy; 2 cytoskeletal organization, through fluorescence microscopy; and 3 membrane overexpression of adhesion molecules, employing ELISA and immunostaining. Upon stimulation with TNF-α (10 ng/mL for 20 h, for all three endothelial cells, the mechanical stiffness increased by about 50% with a mean apparent elastic modulus of E ~5 ± 0.5 kPa (~3.3 ± 0.35 kPa for the control cells; the density of F-actin filaments increased in the apical and median planes; and the ICAM-1 receptors were overexpressed compared with

  9. CORRELATIONS AMONG EXPRESSION OF ANGIOPOIETIN-1 TO CLINICAL PATHOLOGICAL CHARACTERISTICS AN ANGIO- GENESIS IN ORAL SQUAMOUS CELL CARCINOMA

    Institute of Scientific and Technical Information of China (English)

    LI Chao; CHEN Jian-chao; WANG Zhao-hui; ZHANG Bing; LI Bin; SONG Yu-feng

    2006-01-01

    Objective: To study the expression and the significance of Angiopoietin-1 (Ang-1) through observing the correlations among the expression of Ang-1 to clinicopathologic characteristics and microvessel density (MVD) in oral squamous cell carcinoma (OSCC). Methods: Expressions of Angiopoietin-1 and CD34 in 41 human OSCC tissues, 30 adjacent noncancerous oral tissues and 10 normal oral mucosas were detected by immunohistochemical SABC method. MCD was also assessed. Results: Of the 41 OSCC tissues, 41.46% (17/41) was Ang-1 positive. The expression of Ang-1 was significantly lower in OSCC than that in adjacent noncancerous oral tissues (P<0.05) and normal oral mucosa (P<0.05). The Ang-1 expression was significantly higher in high differentiated tumor than that in moderately differentiated tumor (P<0.05). The MVD was significantly higher in Ang-1-negative OSCC than in Ang-1-positive OSCC (P<0.01), and negatively correlated with the expression of Ang-1 (r=-0.32, P<0.05). Conclusion: Down-regulated expression of Ang-1 may play a crucial role in the development of OSCC. It negatively regulated the angiogenesis of tumor.

  10. Immunophenotypic Characterization of Human Bone Marrow Mast Cells. A Flow Cytometric Study of Normal and Pathological Bone Marrow Samples

    Directory of Open Access Journals (Sweden)

    Luis Escribano

    1998-01-01

    Full Text Available The goal of the present paper was to define the immunophenotype of bone marrow mast cells (BMMC from healthy controls and patients with hematologic malignancies (HM based on the use of multiple stainings with monoclonal antibodies analyzed by flow cytometry. Our results show that BMMC from both groups of individuals display a similar but heterogenous immunophenotype. The overall numbers of BMMC are higher in the HM group of individuals (p = 0.08. Three patterns of antigen expression were detected: (1 markers constantly positive in all cases analyzed (CD9, CD29, CD33, CD43, CD44, CD49d, CD49e, CD51, CD71, CD117, and FcεRI, (2 antigens that were constantly negative (CD1a, CD2, CD3, CD5, CD6, CD11a, CD14, CD15, CD16, CD19, CD20, CD21, CD23, CD25, CD30, CD34, CD38, CD41a, CD42b, CD65, CD66b, HLA-DR, and CD138, and (3 markers that were positive in a variable proportion of cases – CD11b (50%, CD11c (77%, CD13 (40%, CD18 (20%, CD22 (68%, CD35 (27%, CD40 (67%, CD54 (88% and CD61 (40%. In addition, BMMC from all cases explored were CD45+, and this antigen was expressed at an intensity similar to that of mature granulocytes.

  11. Adult T-cell leukemia-lymphoma: a clinico-pathologic study of twenty-six patients from Martinique.

    Science.gov (United States)

    Plumelle, Y; Pascaline, N; Nguyen, D; Panelatti, G; Jouannelle, A; Jouault, H; Imbert, M

    1993-01-01

    Twenty-six cases of adult T-cell leukemia/lymphoma (ATLL) were identified between 1983 and 1991 in Martinique (French West Indies). There were 14 men and 12 women, all of mixed racial descent and born in Martinique. Their ages ranged from 23 to 95 years. The main clinical and laboratory features at initial presentation were peripheral lymphadenopathy (22 cases), hepatomegaly (11 cases), splenomegaly (10 cases), cutaneous lesions (12 cases), hypercalcemia (16 cases), refractory infection by Strongyloides stercoralis (12 cases), and pre-existing autoimmune disorders (4 cases). All patients had absolute lymphocytosis with circulating pleomorphic abnormal lymphocytes. The prognosis was poor, with most patients (20 cases) surviving for less than 6 months. Although the overall clinicopathologic features of ATLL in this series are similar to those described in previous reports, we observed three additional points of interest: a high association with Strongyloides infection, an increased incidence of tropical spastic paresis/HTLV-1 associated myelopathy (TSP/HAM) among the relatives of the patients (5 cases), and the presence of prior collagen vascular diseases. PMID:8113152

  12. Domoic Acid Toxicologic Pathology: A Review

    Directory of Open Access Journals (Sweden)

    Olga M. Pulido

    2008-05-01

    Full Text Available Domoic acid was identified as the toxin responsible for an outbreak of human poisoning that occurred in Canada in 1987 following consumption of contaminated blue mussels [Mytilus edulis]. The poisoning was characterized by a constellation of clinical symptoms and signs. Among the most prominent features described was memory impairment which led to the name Amnesic Shellfish Poisoning [ASP]. Domoic acid is produced by certain marine organisms, such as the red alga Chondria armata and planktonic diatom of the genus Pseudo-nitzschia. Since 1987, monitoring programs have been successful in preventing other human incidents of ASP. However, there are documented cases of domoic acid intoxication in wild animals and outbreaks of coastal water contamination in many regions world-wide. Hence domoic acid continues to pose a global risk to the health and safety of humans and wildlife. Several mechanisms have been implicated as mediators for the effects of domoic acid. Of particular importance is the role played by glutamate receptors as mediators of excitatory neurotransmission and the demonstration of a wide distribution of these receptors outside the central nervous system, prompting the attention to other tissues as potential target sites. The aim of this document is to provide a comprehensive review of ASP, DOM induced pathology including ultrastructural changes associated to subchronic oral exposure, and discussion of key proposed mechanisms of cell/tissue injury involved in DOM induced brain pathology and considerations relevant to food safety and human health.

  13. Mechanisms involved in ceramide-induced cell cycle arrest in human hepatocarcinoma cells

    Institute of Scientific and Technical Information of China (English)

    Jing Wang; Xiao-Wen Lv; Jie-Ping Shi; Xiao-Song Hu

    2007-01-01

    AIM:To investigate the effect of ceramide on the cell cycle in human hepatocarcinoma Bel7402 cells.Possible molecular mechanisms were explored.METHODS:[3-(4,5)-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide(MTT)assay,plasmid transfection,reporter assay,FACS and Western blotting analyses were employed to investigate the effect and the related molecular mechanisms of C2-ceramide on the cell cycle of Bel7402 cells.RESULTS:C2-ceramide was found to inhibit the growth of Bel7402 cells by inducing cell cycle arrest.During the process,the expression of p21 protein increased,while that of cyclinD1,phospho-ERK1/2 and c-myc decreased.Furthermore,the level of CDK7 was downregulated,while the transcriptional activity of PPARγ was upregulated.Addition of GW9662,which is a PPARγ specific antagonist,could reserve the modulation action on CDK7.CONCLUSION:Our results support the hypothesis that cell cycle arrest induced by C2-ceramide may be mediated via accumulation of p21 and reduction of cyclinD1 and CDK7,at least partly,through PPARγ activation.The ERK signaling pathway was involved in this process.

  14. Blood-based biomarkers of microvascular pathology in Alzheimer's disease.

    LENUS (Irish Health Repository)

    Ewers, Michael

    2012-02-01

    Sporadic Alzheimer\\'s disease (AD) is a genetically complex and chronically progressive neurodegenerative disorder with molecular mechanisms and neuropathologies centering around the amyloidogenic pathway, hyperphosphorylation and aggregation of tau protein, and neurofibrillary degeneration. While cerebrovascular changes have not been traditionally considered to be a central part of AD pathology, a growing body of evidence demonstrates that they may, in fact, be a characteristic feature of the AD brain as well. In particular, microvascular abnormalities within the brain have been associated with pathological AD hallmarks and may precede neurodegeneration. In vivo assessment of microvascular pathology provides a promising approach to develop useful biological markers for early detection and pathological characterization of AD. This review focuses on established blood-based biological marker candidates of microvascular pathology in AD. These candidates include plasma concentration of vascular cell adhesion molecule-1 (VCAM-1) and intercellular adhesion molecule-1 (ICAM-1) that are increased in AD. Measures of endothelial vasodilatory function including endothelin (ET-1), adrenomedullin (ADM), and atrial natriuretic peptide (ANP), as well as sphingolipids are significantly altered in mild AD or during the predementia stage of mild cognitive impairment (MCI), suggesting sensitivity of these biomarkers for early detection and diagnosis. In conclusion, the emerging clinical diagnostic evidence for the value of blood-based microvascular biomarkers in AD is promising, however, still requires validation in phase II and III diagnostic trials. Moreover, it is still unclear whether the described protein dysbalances are early or downstream pathological events and how the detected systemic microvascular alterations relate to cerebrovascular and neuronal pathologies in the AD brain.

  15. Biosorption mechanism of Cr (Ⅵ) onto cells of Synechococcus sp.

    Institute of Scientific and Technical Information of China (English)

    SHEN Li; XIA Jin-lan; HE Huan; NIE Zhen-yuan; QIU Guan-zhou

    2007-01-01

    The biosorption mechanism of Cr (Ⅵ) ions on Synechococcus sp. biosorbent was studied by analyzing the biosorption kinetics as well as speciation change and bond formation during the biosorption process. The kinetics study shows that the adsorption process of Cr (Ⅵ) consists of a very fast stage in the first several minutes, in which more than half of the saturation adsorption is attained, and a slower stage that approximately follows the first order kinetic model, basically Freundlich isotherm models were observed. Comparative studies of FT-IR spectra of K2Cr2O7, free cells ofSynechococcus sp, and Cr-bound cells ofSynechococcus sp.show that the speciation of chromium that binds to the cells of Synechococcus sp. is Cr (Ⅲ), instead of Cr (Ⅵ), and the carboxylic,alcoholic, amido and amino groups may be involved in the binding of Cr (Ⅲ). Integrative analyses of the surface electric potential,the effect of pH value on adsorption behavior of Cr (Ⅵ), and the results of FT-IR show that the biosorption of Cr (Ⅵ) follows two subsequent steps, biosorption of Cr2O72- by electrostatical force at the protonated active sites and reduction of Cr2O72- to Cr3+ by the reductive groups on the surface of the biosorbents.

  16. How Tissue Mechanical Properties Affect Enteric Neural Crest Cell Migration

    Science.gov (United States)

    Chevalier, N. R.; Gazguez, E.; Bidault, L.; Guilbert, T.; Vias, C.; Vian, E.; Watanabe, Y.; Muller, L.; Germain, S.; Bondurand, N.; Dufour, S.; Fleury, V.

    2016-02-01

    Neural crest cells (NCCs) are a population of multipotent cells that migrate extensively during vertebrate development. Alterations to neural crest ontogenesis cause several diseases, including cancers and congenital defects, such as Hirschprung disease, which results from incomplete colonization of the colon by enteric NCCs (ENCCs). We investigated the influence of the stiffness and structure of the environment on ENCC migration in vitro and during colonization of the gastrointestinal tract in chicken and mouse embryos. We showed using tensile stretching and atomic force microscopy (AFM) that the mesenchyme of the gut was initially soft but gradually stiffened during the period of ENCC colonization. Second-harmonic generation (SHG) microscopy revealed that this stiffening was associated with a gradual organization and enrichment of collagen fibers in the developing gut. Ex-vivo 2D cell migration assays showed that ENCCs migrated on substrates with very low levels of stiffness. In 3D collagen gels, the speed of the ENCC migratory front decreased with increasing gel stiffness, whereas no correlation was found between porosity and ENCC migration behavior. Metalloprotease inhibition experiments showed that ENCCs actively degraded collagen in order to progress. These results shed light on the role of the mechanical properties of tissues in ENCC migration during development.

  17. Cell mechanics and stress: from molecular details to the 'universal cell reaction' and hormesis.

    Science.gov (United States)

    Agutter, Paul S

    2007-04-01

    The 'universal cell reaction' (UCR), a coordinated biphasic response to external (noxious and other) stimuli observed in all living cells, was described by Nasonov and his colleagues in the mid-20th century. This work has received no attention from cell biologists in the West, but the UCR merits serious consideration. Although it is non-specific, it is likely to be underpinned by precise mechanisms and, if these mechanisms were characterized and their relationship to the UCR elucidated, then our understanding of the integration of cellular function could be improved. As a step towards identifying such mechanisms, I review some recent advances in understanding cell mechanics and the stress response and I suggest potentially testable hypotheses. There is a particular need for time-course studies of cellular responses to different stimulus doses or intensities. I also suggest a correspondence with hormesis; re-investigation of the UCR using modern biophysical and molecular-biological techniques might throw light on this much-discussed phenomenon.

  18. Plumbagin induces cell death through a copper-redox cycle mechanism in human cancer cells.

    Science.gov (United States)

    Nazeem, S; Azmi, Asfar S; Hanif, Sarmad; Ahmad, Aamir; Mohammad, Ramzi M; Hadi, S M; Kumar, K Sateesh

    2009-09-01

    Plumbagin, a naphthoquinone derived from the medicinal plant Plumbago zeylanica has been shown to exert anticancer and anti-proliferative activities in cells in culture as well as animal tumor models. In our previous paper, we have reported the cytotoxic action of plumbagin in plasmid pBR322 DNA as well as human peripheral blood lymphocytes through a redox mechanism involving copper. Copper has been shown to be capable of mediating the action of several plant-derived compounds through production of reactive oxygen species (ROS). The objective of the present study was to determine whether plumbagin induces apoptosis in human cancer cells through the same mechanism which we proposed earlier. Using 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium, inner salt assay, 3-(4,5-B-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay for cell growth inhibition, histone/DNA ELISA, homogeneous caspase-3/7 assay for apoptosis as well as alkaline comet assay for DNA single-strand breaks detection in this report, we confirm that plumbagin causes effective cell growth inhibition, induces apoptosis and generates single-strand breaks in cancer cells. Incubation of cancer cells with scavengers of ROS and neocuproine inhibited the cytotoxic action of plumbagin proving that generation of ROS and Cu(I) are the critical mediators in plumbagin-induced cell growth inhibition. This study is the first to investigate the copper-mediated anticancer mechanism of plumbagin in human cancer cells and these properties of plumbagin could be further explored for the development of anticancer agents with higher therapeutic indices, especially for skin cancer.

  19. Adherens junction distribution mechanisms during cell-cell contact elongation in Drosophila.

    Directory of Open Access Journals (Sweden)

    Gabrielle Goldenberg

    Full Text Available During Drosophila gastrulation, amnioserosa (AS cells flatten and spread as an epithelial sheet. We used AS morphogenesis as a model to investigate how adherens junctions (AJs distribute along elongating cell-cell contacts in vivo. As the contacts elongated, total AJ protein levels increased along their length. However, genetically blocking this AJ addition indicated that it was not essential for maintaining AJ continuity. Implicating other remodeling mechanisms, AJ photobleaching revealed non-directional lateral mobility of AJs along the elongating contacts, as well as local AJ removal from the membranes. Actin stabilization with jasplakinolide reduced AJ redistribution, and live imaging of myosin II along elongating contacts revealed fragmented, expanding and contracting actomyosin networks, suggesting a mechanism for lateral AJ mobility. Actin stabilization also increased total AJ levels, suggesting an inhibition of AJ removal. Implicating AJ removal by endocytosis, clathrin endocytic machinery accumulated at AJs. However, dynamin disruption had no apparent effect on AJs, suggesting the involvement of redundant or dynamin-independent mechanisms. Overall, we propose that new synthesis, lateral diffusion, and endocytosis play overlapping roles to populate elongating cell-cell contacts with evenly distributed AJs in this in vivo system.

  20. 基底细胞癌29例临床病理分析%Clinical and pathological analysis of 29 cases of basal cell carcinoma

    Institute of Scientific and Technical Information of China (English)

    周红; 陈敏慧

    2012-01-01

    Objective: To study the clinical features of skin basal cell carcinoma. Methods: Data of 29 cases of basal cell carcinoma was analyzed. Results: The ratio of male and female in these patients was 1: 1. 23. Age ranged from 36 to 81, patients over 50 - years - old of 24 patients was 82.76%. The most common type of nodules was solid (16 cases 55. 17% ). Conclusion: This disease developed more in old person with long term sun exposure.Pathological examination in the correct diagnosis, treatment and prognosis plays an important role.%目的:探讨皮肤基底细胞癌(basal cell carcinoma.BCC)临床病理特点及诱发因素,提高对该病的诊断水平.方法:对29例基底细胞癌患者的临床病理资料进行综合分析.结果:本组患者中男性13例,女性16例,男女比例1:1.23,年龄36 -81岁,其中≥50岁24例(82.76%),农民居多,以结节型(实性)最多见(16例,55.17%).结论:基底细胞癌的发病以中老年为主,好发于头面部等暴晒部位,基底细胞癌的发生与慢性长期日光照射密切相关,病理检查对该病的正确诊断、治疗及预后判断起着重要作用.

  1. Truncation and Activation of Dual Specificity Tyrosine Phosphorylation-regulated Kinase 1A by Calpain I: A MOLECULAR MECHANISM LINKED TO TAU PATHOLOGY IN ALZHEIMER DISEASE.

    Science.gov (United States)

    Jin, Nana; Yin, Xiaomin; Gu, Jianlan; Zhang, Xinhua; Shi, Jianhua; Qian, Wei; Ji, Yuhua; Cao, Maohong; Gu, Xiaosong; Ding, Fei; Iqbal, Khalid; Gong, Cheng-Xin; Liu, Fei

    2015-06-12

    Hyperphosphorylation and dysregulation of exon 10 splicing of Tau are pivotally involved in pathogenesis of Alzheimer disease (AD) and/or other tauopathies. Alternative splicing of Tau exon 10, which encodes the second microtubule-binding repeat, generates Tau isoforms containing three and four microtubule-binding repeats, termed 3R-Taus and 4R-Taus, respectively. Dual specificity tyrosine-phosphorylation-regulated kinase 1A (Dyrk1A) lies at the Down syndrome critical region of chromosome 21. Overexpression of this kinase may contribute to the early Tau pathology in Down syndrome via phosphorylation of Tau and dysregulation of Tau exon 10. Here, we report that Dyrk1A was truncated at the C terminus and was associated with overactivation of calpain I in AD brain. Calpain I proteolyzed Dyrk1A in vitro first at the C terminus and further at the N terminus and enhanced its kinase activity toward Tau via increased Vmax but not Km. C-terminal truncation of Dyrk1A resulted in stronger activity than its full-length protein in promotion of exon 10 exclusion and phosphorylation of Tau. Dyrk1A was truncated in kainic acid-induced excitotoxic mouse brains and coincided with an increase in 3R-Tau expression and phosphorylation of Tau via calpain activation. Moreover, truncation of Dyrk1A was correlated with an increase in the ratio of 3R-Tau/4R-Tau and Tau hyperphosphorylation in AD brain. Collectively, these findings suggest that truncation/activation of Dyrk1A by Ca(2+)/calpain I might contribute to Tau pathology via promotion of exon 10 exclusion and hyperphosphorylation of Tau in AD brain. PMID:25918155

  2. Autoimmune muscular pathologies.

    Science.gov (United States)

    Dalakas, M C

    2005-05-01

    The T cell-mediated mechanism responsible for Polymyositis and inclusion Body Myositis and the complement-mediated microangiopathy associated with Dermatomyositis are reviewed. The management of autoimmune myopathies with the presently available immunotherapeutic agents as well as new therapies and ongoing trials are discussed.

  3. Type IV Collagens and Basement Membrane Diseases: Cell Biology and Pathogenic Mechanisms.

    Science.gov (United States)

    Mao, Mao; Alavi, Marcel V; Labelle-Dumais, Cassandre; Gould, Douglas B

    2015-01-01

    Basement membranes are highly specialized extracellular matrices. Once considered inert scaffolds, basement membranes are now viewed as dynamic and versatile environments that modulate cellular behaviors to regulate tissue development, function, and repair. Increasing evidence suggests that, in addition to providing structural support to neighboring cells, basement membranes serve as reservoirs of growth factors that direct and fine-tune cellular functions. Type IV collagens are a major component of all basement membranes. They evolved along with the earliest multicellular organisms and have been integrated into diverse fundamental biological processes as time and evolution shaped the animal kingdom. The roles of basement membranes in humans are as complex and diverse as their distributions and molecular composition. As a result, basement membrane defects result in multisystem disorders with ambiguous and overlapping boundaries that likely reflect the simultaneous interplay and integration of multiple cellular pathways and processes. Consequently, there will be no single treatment for basement membrane disorders, and therapies are likely to be as varied as the phenotypes. Understanding tissue-specific pathology and the underlying molecular mechanism is the present challenge; personalized medicine will rely upon understanding how a given mutation impacts diverse cellular functions.

  4. Cell wall pectic arabinans influence the mechanical properties of Arabidopsis thaliana inflorescence stems and their response to mechanical stress.

    Science.gov (United States)

    Verhertbruggen, Yves; Marcus, Susan E; Chen, Jianshe; Knox, J Paul

    2013-08-01

    Little is known of the dynamics of plant cell wall matrix polysaccharides in response to the impact of mechanical stress on plant organs. The capacity of the imposition of a mechanical stress (periodic brushing) to reduce the height of the inflorescence stem of Arabidopsis thaliana seedlings has been used to study the role of pectic arabinans in the mechanical properties and stress responsiveness of a plant organ. The arabinan-deficient-1 (arad1) mutation that affects arabinan structures in epidermal cell walls of inflorescence stems is demonstrated to reduce the impact on inflorescence stem heights caused by mechanical stress. The arabinan-deficient-2 (arad2) mutation, that does not have detectable impact on arabinan structures, is also shown to reduce the impact on stem heights caused by mechanical stress. The LM13 linear arabinan epitope is specifically detected in epidermal cell walls of the younger, flexible regions of inflorescence stems and increases in abundance at the base of inflorescence stems in response to an imposed mechanical stress. The strain (percentage deformation) of stem epidermal cells in the double mutant arad1 × arad2 is lower in unbrushed plants than in wild-type plants, but rises to wild-type levels in response to brushing. The study demonstrates the complexity of arabinan structures within plant cell walls and also that their contribution to cell wall mechanical properties is a factor influencing responsiveness to mechanical stress.

  5. Neuronal activity enhances tau propagation and tau pathology in vivo.

    Science.gov (United States)

    Wu, Jessica W; Hussaini, S Abid; Bastille, Isle M; Rodriguez, Gustavo A; Mrejeru, Ana; Rilett, Kelly; Sanders, David W; Cook, Casey; Fu, Hongjun; Boonen, Rick A C M; Herman, Mathieu; Nahmani, Eden; Emrani, Sheina; Figueroa, Y Helen; Diamond, Marc I; Clelland, Catherine L; Wray, Selina; Duff, Karen E

    2016-08-01

    Tau protein can transfer between neurons transneuronally and trans-synaptically, which is thought to explain the progressive spread of tauopathy observed in the brain of patients with Alzheimer's disease. Here we show that physiological tau released from donor cells can transfer to recipient cells via the medium, suggesting that at least one mechanism by which tau can transfer is via the extracellular space. Neuronal activity has been shown to regulate tau secretion, but its effect on tau pathology is unknown. Using optogenetic and chemogenetic approaches, we found that increased neuronal activity stimulates the release of tau in vitro and enhances tau pathology in vivo. These data have implications for disease pathogenesis and therapeutic strategies for Alzheimer's disease and other tauopathies. PMID:27322420

  6. Immunology Mechanism of CD4+ CD25 T Regulatory Cells Acting on Effector T Cells

    Institute of Scientific and Technical Information of China (English)

    FENGNing-han; WUHong-fei; WUJun; ZHANGWei; SUIYuan-gen; HEHou-guang; ZHANGChun-lei; ZHENGJun-song

    2004-01-01

    Objective: To detect the inhibiting co-stimulating molecule CTLA4 and cytokines secreted by Treg cells, and explore the immunology mechanism of T regulatory cells acting on effector T cells in co-cultured system(CCS) and separating-cultured system(SCS). Methods: Detecting the percentage of CTLA4 and CD28 expressed on the Treg ceils and effector T ceils, and then adding Treg cells to mixed lymphocyte reaction(MLR) system in CCS and TransWeil Milliceil-PCF SCS, at the same time, adding or not adding anti-IL-10 or anti-TGF.II1 to the reacting systems, examining the inhibitory capacity of Treg ceils exerting on the MLR. Results: Compared with effector T cells, Treg cells expressed higher level CTLA4 and secreted much more IL-10 and TGF-β(P<0.01). The inhibitory capacity of Treg cells co-cultured with effector T ceils is much stronger than that in separating cultured group(P<0.01). Moreover, the inhibiting rate of Treg ceils exerting on effector T ceils through secretin_g IL-10 was more powerful than that through secreting TGF-β1 (P<0.01). Coaclusion: Both ceil-to-ceil contact and cytokines secretion mechanisms are involved in CD4+ CD25+ Treg ceils operating function. However, the former is more important. Intresfingly, we for the first time pointfound that IL-10 plays more powerful roles than TGF-β1 in the cytokines secretion mechanism.

  7. Frequency locking in hair cells: Distinguishing between distinct resonant mechanisms

    CERN Document Server

    Edri, Yuval; Yochelis, Arik

    2016-01-01

    The auditory system displays remarkable mechanical sensitivity and frequency discrimination. These attributes have been shown to rely on an amplification process, which requires biochemical feedback loops. In some systems, the active process was shown to lead to spontaneous oscillations of hair cell bundles. In the last decade, models that display proximity to an oscillatory onset (a.k.a. Hopf bifurcation) have gained increasing support due to many advantages in explaining the hearing phenomenology. Particularly, they exhibit resonant responses to distinct frequencies of incoming sound waves. Unlike previous studies, two types of driving forces are being examined: additive, in which the external forcing term does not couple directly on the systems observable (passive coupling), and parametric, in which the forcing term directly affects the observable and thus intrinsically modifies the systems properties (active coupling). By applying universal principles near the Hopf bifurcation onset, we find several funda...

  8. Chemical degradation mechanisms of membranes for alkaline membrane fuel cells

    International Nuclear Information System (INIS)

    Chemical degradation mechanisms of membranes for alkaline membrane fuel cells have been investigated using density functional theory (DFT). We have elucidated that the aryl-ether moiety of membranes is one of the weakest site against attack of hydroxide ions. The results of DFT calculations for hydroxide initiated aryl-ether cleavage indicated that the aryl-ether cleavage occurred prior to degradation of cationic functional group. Such a weak nature of the aryl-ether group arises from the electron deficiency of the aryl group as well as the low bond dissociation energy. The DFT results suggests that removal of the aryl-ether group in the membrane should enhance the stability of membranes under alkaline conditions. In fact, an ether fee poly(phenylene) membrane exhibits excellent stability against the attack from hydroxide ions

  9. Chemical degradation mechanisms of membranes for alkaline membrane fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    Choe, Yoong-Kee [National Institute of Advanced Industrial Science and Technology, Umezono 1-1-1, Tsukuba (Japan); Henson, Neil J.; Kim, Yu Seung [Los Alamos National Laboratory, Los Alamos, NM (United States)

    2015-12-31

    Chemical degradation mechanisms of membranes for alkaline membrane fuel cells have been investigated using density functional theory (DFT). We have elucidated that the aryl-ether moiety of membranes is one of the weakest site against attack of hydroxide ions. The results of DFT calculations for hydroxide initiated aryl-ether cleavage indicated that the aryl-ether cleavage occurred prior to degradation of cationic functional group. Such a weak nature of the aryl-ether group arises from the electron deficiency of the aryl group as well as the low bond dissociation energy. The DFT results suggests that removal of the aryl-ether group in the membrane should enhance the stability of membranes under alkaline conditions. In fact, an ether fee poly(phenylene) membrane exhibits excellent stability against the attack from hydroxide ions.

  10. Cell-autonomous effector mechanisms against mycobacterium tuberculosis.

    Science.gov (United States)

    MacMicking, John D

    2014-10-01

    Few pathogens run the gauntlet of sterilizing immunity like Mycobacterium tuberculosis (Mtb). This organism infects mononuclear phagocytes and is also ingested by neutrophils, both of which possess an arsenal of cell-intrinsic effector mechanisms capable of eliminating it. Here Mtb encounters acid, oxidants, nitrosylating agents, and redox congeners, often exuberantly delivered under low oxygen tension. Further pressure is applied by withholding divalent Fe²⁺, Mn²⁺, Cu²⁺, and Zn²⁺, as well as by metabolic privation in the form of carbon needed for anaplerosis and aromatic amino acids for growth. Finally, host E3 ligases ubiquinate, cationic peptides disrupt, and lysosomal enzymes digest Mtb as part of the autophagic response to this particular pathogen. It is a testament to the evolutionary fitness of Mtb that sterilization is rarely complete, although sufficient to ensure most people infected with this airborne bacterium remain disease-free. PMID:25081628

  11. EXPRESSION OF P53 GENE IN ORAL SQUAMOUS CELL CARCINOMA AND ITS RELATION WITH CLINICAL AND PATHOLOGICAL PARAMETERS AND PROGNOSIS OF PATIENTS

    Institute of Scientific and Technical Information of China (English)

    毛驰; 卢勇; 赖钦声; 夏雨和; 杨橙

    1995-01-01

    One hundred and eleven cases of cral squamous cell carcinoma (OSCC) were examined for overexpression of p53 protein by using immunchistochemical technique.Association between p53 protein overexpression and clinical and pathological parameters as well as prognosis of patients were also analyzed. p53 protein overexpression was commonly observed (69.4%) in OSCC and may be used as a marker of carcinogenesis of OSCC.The level of p53 protein overexpression is correlated with the lowet three and five-year survival rate of OSCC.The presence of absence of p53 overexpression was not correlated with sex,age,site of tumor,size of tumor,degree of differentiation,node status,and clinical stage in OSCC.Single factor COX proportinoal hazards regression model analysis indicated that there was no significant association between p53 overexpression and prognosis of OSCC,Multivariable COX model analysis failed to establish effective life function of risk rate function,These showed that all the parameters analyzed in this study as well as p53 overexpression were not significant and effective risk factors of prognosis for patients wich OSCC.

  12. Freezing osteoblast cells attached to hydroxyapatite discs and glass coverslips: Mechanisms of damage

    Institute of Scientific and Technical Information of China (English)

    McGRATH; John

    2007-01-01

    Damage mechanisms for osteoblast cells (OBs) attached to hydroxyapatite (HA) discs and glass coverslips were comprehensively investigated. Cell-cell, cell-matrix interaction altered the cryobiological properties of cells. Attached cells were sub- ject to more severe mechanical damage than isolated cells because attached cells had larger contacting area with ice and the three dimensional movements of iso- lated cells made them more flexible than attached cells that could only deform in one dimension. Results showed that the viability of attached OB cells decreased significantly compared with the viability of isolated OB cells under the same cryo- preservation procedure. Extracellular ice, differential thermal contraction, and mechanical stresses were the major damaging factors for OB cells attached to HA discs and glass coverslips.

  13. Freezing osteoblast cells attached to hydroxyapatite discs and glass coverslips: Mechanisms of damage

    Institute of Scientific and Technical Information of China (English)

    LIU BaoLin; McGRATH John

    2007-01-01

    Damage mechanisms for osteoblast cells (OBs) attached to hydroxyapatite (HA)discs and glass coverslips were comprehensively investigated. Cell-cell, cell-matrix interaction altered the cryobiological properties of cells. Attached cells were subject to more severe mechanical damage than isolated cells because attached cells had larger contacting area with ice and the three dimensional movements of isolated cells made them more flexible than attached cells that could only deform in one dimension. Results showed that the viability of attached OB cells decreased significantly compared with the viability of isolated OB cells under the same cryopreservation procedure. Extracellular ice, differential thermal contraction, and mechanical stresses were the major damaging factors for OB cells attached to HA discs and glass coverslips.

  14. 我国烧伤病理学研究的回顾与展望%A review of 50 years investigation on burn pathology in China and its prospect

    Institute of Scientific and Technical Information of China (English)

    史景泉; 陈意生

    2008-01-01

    A great achievement has been made on burn pathology research in China since 1958.These advances include: pathological changes in burn wound, the healing process of bum wound and its mechanism modulated by growth factors especially hFGF, intermingted transplantation of allo-skin or xenoskin with auto-skin for coverage of extensive third degree bums, characteristic postbum inflammatory reaction, pathological changes and evolution in various internal organs, multiple organ dysfunction syndrome (MODS),pathological changes in phosphorus burn, pathological changes in endotoxemia in burn, the role of vascular endothelial cell in pathogenesis of postburn visceral organ dysfunction as well as steam and smoke inhalation injury.

  15. Splitting the cell, building the organism: Mechanisms of cell division in metazoan embryos.

    Science.gov (United States)

    Kumar, Megha; Pushpa, Kumari; Mylavarapu, Sivaram V S

    2015-07-01

    The unicellular metazoan zygote undergoes a series of cell divisions that are central to its development into an embryo. Differentiation of embryonic cells leads eventually to the development of a functional adult. Fate specification of pluripotent embryonic cells occurs during the early embryonic cleavage divisions in several animals. Early development is characterized by well-known stages of embryogenesis documented across animals--morulation, blastulation, and morphogenetic processes such as gastrulation, all of which contribute to differentiation and tissue specification. Despite this broad conservation, there exist clearly discernible morphological and functional differences across early embryonic stages in metazoans. Variations in the mitotic mechanisms of early embryonic cell divisions play key roles in governing these gross differences that eventually encode developmental patterns. In this review, we discuss molecular mechanisms of both karyokinesis (nuclear division) and cytokinesis (cytoplasmic separation) during early embryonic divisions. We outline the broadly conserved molecular pathways that operate in these two stages in early embryonic mitoses. In addition, we highlight mechanistic variations in these two stages across different organisms. We finally discuss outstanding questions of interest, answers to which would illuminate the role of divergent mitotic mechanisms in shaping early animal embryogenesis.

  16. Molecular mechanisms of pharmacological doses of ascorbate on cancer cells.

    Science.gov (United States)

    Venturelli, Sascha; Sinnberg, Tobias W; Niessner, Heike; Busch, Christian

    2015-06-01

    Intravenous application of high-dose ascorbate (vitamin C) has been used in complementary medicine since the 1970s to treat cancer patients. In recent years it became evident that high-dose ascorbate in the millimolar range bears selective cytotoxic effects on cancer cells in vitro and in vivo. This anticancer effect is dose dependent, catalyzed by serum components and mediated by reactive oxygen species and ascorbyl radicals, making ascorbate a pro-oxidative pro-drug that catalyzes hydrogen peroxide production in tissues instead of acting as a radical scavenger. It further depends on HIF-1 signaling and oxygen pressure, and shows a strong epigenetic signature (alteration of DNA-methylation and induction of tumor-suppressing microRNAs in cancer cells). The detailed understanding of ascorbate-induced antiproliferative molecular mechanisms warrants in-depth preclinical evaluation in cancer-bearing animal models for the optimization of an efficacious therapy regimen (e.g., combination with hyperbaric oxygen or O2-sensitizers) that subsequently need to be evaluated in clinical trials. PMID:26065536

  17. Diastolic function alteration mechanisms in physiologic hypertrophy versus pathologic hypertrophy are elucidated by model-based Doppler E-wave analysis

    Directory of Open Access Journals (Sweden)

    Simeng Zhu

    2014-12-01

    Full Text Available Athletic training can result in increased left ventricular (LV wall thickness, termed physiologic hypertrophy (PhH. By contrast, pathologic hypertrophy (PaH can be due to hypertension, aortic stenosis, or genetic mutation causing hypertrophic cardiomyopathy (HCM. Because morphologic (LV dimension, wall thickness, mass, etc. and functional index similarities (LV ejection fraction, cardiac output, peak filling rate, etc. limit diagnostic specificity, ability to differentiate between PhH and PaH is important. Conventional echocardiographic diastolic function (DF indexes have limited ability to differentiate between PhH and PaH and cannot provide information on chamber property (stiffness and relaxation. We hypothesized that kinematic model-based DF assessment can differentiate between PhH and PaH and, by providing chamber properties, has even greater value compared with conventional metrics. For validation, we assessed DF in the following three age-matched groups: pathologic (HCM hypertrophy (PaH, n = 14, PhH (Olympic rowers, PhH, n = 21, and controls (n = 21. Magnetic resonance imaging confirmed presence of both types of hypertrophy and determined LV mass and chamber size. Model-based indexes, chamber stiffness (k, relaxation/viscoelasticity (c, and load (xo and conventional indexes, Epeak (peak of E-wave, ratio of Epeak to Apeak (E/A, E-wave acceleration time (AT, and E-wave deceleration time (DT were computed. We analyzed 1588 E waves distributed as follows: 328 (PaH, 672 (athletes, and 588 (controls. Among conventional indexes, Epeak and E-wave DT were similar between PaH and PhH, whereas E/A and E-wave AT were lower in PaH. Model-based analysis showed that PaH had significantly higher relaxation/viscoelasticity (c and chamber stiffness (k than PhH. The physiologic equation of motion for filling-based derivation of the model provides a mechanistic understanding of the differences between PhH and PaH.

  18. Combined gene/cell therapies provide long-term and pervasive rescue of multiple pathological symptoms in a murine model of globoid cell leukodystrophy

    OpenAIRE

    Ricca, Alessandra; Rufo, Nicole; Ungari, Silvia; Morena, Francesco; Martino, Sabata; Kulik, Wilem; Alberizzi, Valeria; Bolino, Alessandra; Bianchi, Francesca; del Carro, Ubaldo; Biffi, Alessandra; Gritti, Angela

    2015-01-01

    Globoid cell leukodystrophy (GLD) is a lysosomal storage disease caused by deficient activity of β-galactocerebrosidase (GALC). The infantile forms manifest with rapid and progressive central and peripheral demyelination, which represent a major hurdle for any treatment approach. We demonstrate here that neonatal lentiviral vector-mediated intracerebral gene therapy (IC GT) or transplantation of GALC-overexpressing neural stem cells (NSC) synergize with bone marrow transplant (BMT) providing ...

  19. Do long-lived mutant and calorie-restricted mice share common anti-aging mechanisms?—a pathological point of view

    OpenAIRE

    Ikeno, Yuji; Lew, Christie M.; Cortez, Lisa A.; Webb, Celeste R.; Lee, Shuko; Gene B Hubbard

    2006-01-01

    Rodent models are an invaluable resource for studying the mechanism of mammalian aging. In recent years, the availability of transgenic and knockout mouse models has facilitated the study of potential mechanisms of aging. Since 1996, aging studies with several long-lived mutant mice have been conducted. Studies with the long-lived mutant mice, Ames and Snell dwarf, and growth hormone receptor/binding protein knockout mice, are currently providing important clues regarding the role of the grow...

  20. High preoperative and postoperative levels of carcinoembryonic antigen and CYFRA 21-1 indicate poor prognosis in patients with pathological Stage I nonsmall cell lung cancer

    Directory of Open Access Journals (Sweden)

    X Duan

    2015-01-01

    Full Text Available BACKGROUND: Serum carcinoembryonic antigen (CEA and the soluble fragment of cytokeratin 19 (CYFRA 21-1 are supposed to have a prognostic role in patients with nonsmall cell lung cancer (NSCLC after surgery, but it has not been used as an adjunct to the tumor-node-metastasis (TNM staging system to provide therapy options for patients with pathological Stage I NSCLC. This study was designed to investigate the effect of serum levels of CEA and CYFRA 21-1 before and after surgery on the prognosis of patients with Stage I NSCLC. MATERIALS AND METHODS: A retrospective review was performed regarding the medical records and follow-ups of 169 patients with Stage I NSCLC before and after surgery. The patients were divided into three groups based on levels of serum CEA and CYFRA 21-1 before and after surgery: (1 continuously normal-level groups (CEA [NN] and CYFRA 21-1 [NN] groups; (2 declined to normal-level groups (CEA [HN] and CYFRA 21-1 [HN] groups; and (3 continuously high-level groups (CEA [HH] and CYFRA 21-1 [HH] groups. Survival analysis was conducted using the Kaplan-Meier method for each group. The Chi-square or Fisher exact test was employed to compare clinical and pathologic factors at the level of P < 0.05. The prognostic factor was evaluated by the Cox proportional hazards model. RESULTS: Compared with the continuously normal-level groups, the CEA [HN] group was significantly correlated to tumor size (P = 0.011, and the CYFRA 21-1 [HN] group was significantly correlated to tumor type and pathological TNM in addition to tumor size. Five-year survivals were significantly lower (P = 0.004 in the CEA [HH] group (67.3% and the CEA [HN] group (86.5% than in the CEA [NN] group (85.7% and were significantly lower (P < 0.001 in the CYFRA 21-1 [HH] group (47.2% and the CYFRA 21-1 [HN] group (70.1% than in the CYFRA 21-1 [NN] group (90.1%. Multivariate analysis demonstrated that tumor size (21-50 mm, CEA [HH], and CYFRA 21-1 [HH] were independent

  1. Distinct mechanical behavior of HEK293 cells in adherent and suspended states.

    Science.gov (United States)

    Haghparast, Seyed Mohammad Ali; Kihara, Takanori; Miyake, Jun

    2015-01-01

    The mechanical features of individual animal cells have been regarded as indicators of cell type and state. Previously, we investigated the surface mechanics of cancer and normal stromal cells in adherent and suspended states using atomic force microscopy. Cancer cells possessed specific mechanical and actin cytoskeleton features that were distinct from normal stromal cells in adherent and suspended states. In this paper, we report the unique mechanical and actin cytoskeletal features of human embryonic kidney HEK293 cells. Unlike normal stromal and cancer cells, the surface stiffness of adherent HEK293 cells was very low, but increased after cell detachment from the culture surface. Induced actin filament depolymerization revealed that the actin cytoskeleton was the underlying source of the stiffness in suspended HEK293 cells. The exclusive mechanical response of HEK293 cells to perturbation of the actin cytoskeleton resembled that of adherent cancer cells and suspended normal stromal cells. Thus, with respect to their special cell-surface mechanical features, HEK293 cells could be categorized into a new class distinct from normal stromal and cancer cells.

  2. Flocculation protein structure and cell-cell adhesion mechanism in Saccharomyces cerevisiae.

    Science.gov (United States)

    Goossens, Katty; Willaert, Ronnie

    2010-11-01

    Cell-cell adhesion occurs in a broad spectrum of biological processes, of which yeast flocculation is an area of interest for evolutionary scientists to brewers and winemakers. The flocculation mechanism is based on a lectin-carbohydrate interaction but is not yet fully understood, although the first model dates back to the 1950s. This review will update the current understanding of the complex mechanism behind yeast flocculation. Moreover, modern technologies to measure the forces involved in single carbohydrate-lectin interactions, are discussed. The Flo1 protein has been extensively described as the protein responsible for strong flocculation. Recently, more research has been directed to the detailed analysis of this flocculin. Due to the advances in the field of bioinformatics, more information about Flo1p could be obtained via structurally or functionally related proteins. Here, we review the current knowledge of the Flo1 protein, with a strong emphasis towards its structure.

  3. Mechanisms of manganese-induced rat pheochromocytoma (PC12) cell death and cell differentiation.

    Science.gov (United States)

    Roth, Jerome A; Horbinski, Craig; Higgins, Dennis; Lein, Pamela; Garrick, Michael D

    2002-07-01

    Mn is a neurotoxin that leads to a syndrome resembling Parkinson's disease after prolonged exposure to high concentrations. Our laboratory has been investigating the mechanism by which Mn induces neuronal cell death. To accomplish this, we have utilized rat pheochromocytoma (PC12) cells as a model since they possess much of the biochemical machinery associated with dopaminergic neurons. Mn, like nerve growth factor (NGF), can induce neuronal differentiation of PC12 cells but Mn-induced cell differentiation is dependent on its interaction with the cell surface integrin receptors and basement membrane proteins, vitronectin or fibronectin. Similar to NGF, Mn-induced neurite outgrowth is dependent on the phosphorylation and activation of the MAP kinases, ERK1 and 2 (p44/42). Unlike NGF, Mn is also cytotoxic having an IC50 value of approximately 600 microM. Although many apoptotic signals are turned on by Mn, cell death is caused ultimately by disruption of mitochondrial function leading to loss of ATP. RT-PCR and immunoblotting studies suggest that some uptake of Mn into PC12 cells depends on the divalent metal transporter 1 (DMT1). DMT1 exists in two isoforms resulting from alternate splicing of a single gene product with one of the two mRNA species containing an iron response element (IRE) motif downstream from the stop codon. The presence of the IRE provides a binding site for the iron response proteins (IRP1 and 2); binding of either of these proteins could stabilize DMT1 mRNA and would increase expression of the +IRE form of the transporter. Iron and Mn compete for transport into PC12 cells via DMT1, so removal of iron from the culture media enhances Mn toxicity. The two isoforms of DMT1 (+/-IRE) are distributed in different subcellular compartments with the -IRE species selectively present in the nucleus of neuronal and neuronal-like cells. PMID:12224755

  4. Do long-lived mutant and calorie-restricted mice share common anti-aging mechanisms?--a pathological point of view.

    Science.gov (United States)

    Ikeno, Yuji; Lew, Christie M; Cortez, Lisa A; Webb, Celeste R; Lee, Shuko; Hubbard, Gene B

    2006-06-01

    Rodent models are an invaluable resource for studying the mechanism of mammalian aging. In recent years, the availability of transgenic and knockout mouse models has facilitated the study of potential mechanisms of aging. Since 1996, aging studies with several long-lived mutant mice have been conducted. Studies with the long-lived mutant mice, Ames and Snell dwarf, and growth hormone receptor/binding protein knockout mice, are currently providing important clues regarding the role of the growth hormone/insulin like growth factor-1 axis in the aging process. Interestingly, these studies demonstrate that these long-lived mutant mice have physiological characteristics that are similar to the effects of calorie restriction, which has been the most effective experimental manipulation capable of extending lifespan in various species. However, a question remains to be answered: do these long-lived mutant and calorie-restricted mice extend their lifespan through a common underlying mechanism? PMID:19943137

  5. Comparative Transduction Mechanisms of Vestibular Otolith Hair Cells

    Science.gov (United States)

    Baird, Richard A.

    1994-01-01

    Hair cells in the bullfrog vestibular otolith organs regenerate following aminoglycoside ototoxicity. Hair cells in these organs are differentially sensitive to gentamicin, with saccular hair cells and hair cells in the utricular striola being damaged at lower gentamicin concentrations than hair cells in the utricular extrastriola. Regenerating hair cells in these organs have short hair bundles and can be classified into a number of phenotypes using the same morphological criteria used to identify their mature counterparts. Our studies suggest that some supporting cells can convert, or transdifferentiate,into hair cells without an intervening cell division. By stimulating these processes in humans, clinicians may be able to alleviate human deafness and peripheral vestibular disorders by regenerating and replacing lost hair cells. In vivo and in vitro studies were done on cell proliferation and hair cell regeneration.

  6. Systematization of the Mechanism by Which Plasma Irradiation Causes Cell Growth and Tumor Cell Death

    Science.gov (United States)

    Shimizu, Nobuyuki

    2015-09-01

    New methods and technologies have improved minimally invasive surgical treatment and saved numerous patients. Recently, plasma irradiation has been demonstrated that might be useful in medical field and the plasma irradiation device is expected to become practically applicable. Mild plasma coagulator showed some advantages such as hemostasis and adhesion reduction in experimental animal model, but the mechanism of plasma irradiation remains unclear. Our study group aim to clarify the mechanism of plasma irradiation effects, mainly focusing on oxidative stress using cultured cell lines and small animal model. First, a study using cultured cell lines showed that the culture medium that was activated by plasma irradiation (we called this kind of medium as ``PAM'' -plasma activated medium-) induced tumor cell death. Although this effect was mainly found to be due to hydrogen peroxide, the remaining portion was considered as the specific effect of the plasma irradiation and we are now studying focusing on this effect. Second, we established a mouse intra-peritoneal adhesion model and checked biological reaction that occurred in the adhesion part. Histopathological study showed inflammatory cells infiltration into adhesion part and the expression of PTX3 that might involve tissue repair around adhesion part. We also confirmed that cytokines IL-6 and IL-10 might be useful as a marker of adhesion formation in this model. Applying ``PAM'' or mild plasma irradiation in this model, we examine the effects of plasma on inflamed cells. The samples in these experiments would be applied to targeted proteomics analysis, and we aim to demonstrate the systematization of the cell's reaction by plasma irradiation.

  7. Regulation of the Mechanism of TWIST1 Transcription by BHLHE40 and BHLHE41 in Cancer Cells.

    Science.gov (United States)

    Asanoma, Kazuo; Liu, Ge; Yamane, Takako; Miyanari, Yoko; Takao, Tomoka; Yagi, Hiroshi; Ohgami, Tatsuhiro; Ichinoe, Akimasa; Sonoda, Kenzo; Wake, Norio; Kato, Kiyoko

    2015-12-01

    BHLHE40 and BHLHE41 (BHLHE40/41) are basic helix-loop-helix type transcription factors that play key roles in multiple cell behaviors. BHLHE40/41 were recently shown to be involved in an epithelial-to-mesenchymal transition (EMT). However, the precise mechanism of EMT control by BHLHE40/41 remains unclear. In the present study, we demonstrated that BHLHE40/41 expression was controlled in a pathological stage-dependent manner in human endometrial cancer (HEC). Our in vitro assays showed that BHLHE40/41 suppressed tumor cell invasion. BHLHE40/41 also suppressed the transcription of the EMT effectors SNAI1, SNAI2, and TWIST1. We identified the critical promoter regions of TWIST1 for its basal transcriptional activity. We elucidated that the transcription factor SP1 was involved in the basal transcriptional activity of TWIST1 and that BHLHE40/41 competed with SP1 for DNA binding to regulate gene transcription. This study is the first to report the detailed functions of BHLHE40 and BHLHE41 in the suppression of EMT effectors in vitro. Our results suggest that BHLHE40/41 suppress tumor cell invasion by inhibiting EMT in tumor cells. We propose that BHLHE40/41 are promising markers to predict the aggressiveness of each HEC case and that molecular targeting strategies involving BHLHE40/41 and SP1 may effectively regulate HEC progression.

  8. Progress on the pathologic mechanism and potential therapy of androgenic alopecia%脂溢性脱发的发生机制及治疗研究进展

    Institute of Scientific and Technical Information of China (English)

    巫珊; 张海州

    2012-01-01

    Pathologic mechanism and therapeutic methods of androgenic alopecia were discussed. Pathological representations, pathogenesis and therapeutically active ingredients of androgenic alopecia were introduced, and the relationship between cytokines and androgenic alopecia was disclosed. The active ingredients which may inhibit or stimulate related cytokines with traditional treatment for hairloss are presented and its application prospect is also discussed.%综述了脂溢性脱发的发生机制及活性物治疗研究进展。主要介绍了脂溢性脱发的病理表现、发生机制以及治疗活性物的研究现状。重点揭示了相关细胞因子对脂溢性脱发的影响。提出将具有相应细胞因子激励或抑制作用的活性物与常规的功能性成分联合应用在防脱发个人护理品中,将充分发挥其治疗效果,并对其应用前景进行了展望。

  9. Mechanics of Cellulose Synthase Complexes in Living Plant Cells

    Science.gov (United States)

    Zehfroosh, Nina; Liu, Derui; Ramos, Kieran P.; Yang, Xiaoli; Goldner, Lori S.; Baskin, Tobias I.

    The polymer cellulose is one of the major components of the world's biomass with unique and fascinating characteristics such as its high tensile strength, renewability, biodegradability, and biocompatibility. Because of these distinctive aspects, cellulose has been the subject of enormous scientific and industrial interest, yet there are still fundamental open questions about cellulose biosynthesis. Cellulose is synthesized by a complex of transmembrane proteins called ``Cellulose Synthase A'' (CESA) in the plasma membrane. Studying the dynamics and kinematics of the CESA complex will help reveal the mechanism of cellulose synthesis and permit the development and validation of models of CESA motility. To understand what drives these complexes through the cell membrane, we used total internal reflection fluorescence microscopy (TIRFM) and variable angle epi-fluorescence microscopy to track individual, fluorescently-labeled CESA complexes as they move in the hypocotyl and root of living plants. A mean square displacement analysis will be applied to distinguish ballistic, diffusional, and other forms of motion. We report on the results of these tracking experiments. This work was funded by NSF/PHY-1205989.

  10. Molecular Mechanisms by Which a Fucus vesiculosus Extract Mediates Cell Cycle Inhibition and Cell Death in Pancreatic Cancer Cells

    Directory of Open Access Journals (Sweden)

    Ulf Geisen

    2015-07-01

    Full Text Available Pancreatic cancer is one of the most aggressive cancer entities, with an extremely poor 5-year survival rate. Therefore, novel therapeutic agents with specific modes of action are urgently needed. Marine organisms represent a promising source to identify new pharmacologically active substances. Secondary metabolites derived from marine algae are of particular interest. The present work describes cellular and molecular mechanisms induced by an HPLC-fractionated, hydrophilic extract derived from the Baltic brown seaweed Fucus vesiculosus (Fv1. Treatment with Fv1 resulted in a strong inhibition of viability in various pancreatic cancer cell lines. This extract inhibited the cell cycle of proliferating cells due to the up-regulation of cell cycle inhibitors, shown on the mRNA (microarray data and protein level. As a result, cells were dying in a caspase-independent manner. Experiments with non-dividing cells showed that proliferation is a prerequisite for the effectiveness of Fv1. Importantly, Fv1 showed low cytotoxic activity against non-malignant resting T cells and terminally differentiated cells like erythrocytes. Interestingly, accelerated killing effects were observed in combination with inhibitors of autophagy. Our in vitro data suggest that Fv1 may represent a promising new agent that deserves further development towards clinical application.

  11. ADAMs family and relatives in cardiovascular physiology and pathology.

    Science.gov (United States)

    Zhang, Pu; Shen, Mengcheng; Fernandez-Patron, Carlos; Kassiri, Zamaneh

    2016-04-01

    A disintegrin and metalloproteinases (ADAMs) are a family of membrane-bound proteases. ADAM-TSs (ADAMs with thrombospondin domains) are a close relative of ADAMs that are present in soluble form in the extracellular space. Dysregulated production or function of these enzymes has been associated with pathologies such as cancer, asthma, Alzheimer's and cardiovascular diseases. ADAMs contribute to angiogenesis, hypertrophy and apoptosis in a stimulus- and cell type-dependent manner. Among the ADAMs identified so far (34 in mouse, 21 in human), ADAMs 8, 9, 10, 12, 17 and 19 have been shown to be involved in cardiovascular development or cardiomyopathies; and among the 19 ADAM-TSs, ADAM-TS1, 5, 7 and 9 are important in development of the cardiovascular system, while ADAM-TS13 can contribute to vascular disorders. Meanwhile, there remain a number of ADAMs and ADAM-TSs whose function in the cardiovascular system has not been yet explored. The current knowledge about the role of ADAMs and ADAM-TSs in the cardiovascular pathologies is still quite limited. The most detailed studies have been performed in other cell types (e.g. cancer cells) and organs (nervous system) which can provide valuable insight into the potential functions of ADAMs and ADAM-TSs, their mechanism of action and therapeutic potentials in cardiomyopathies. Here, we review what is currently known about the structure and function of ADAMs and ADAM-TSs, and their roles in development, physiology and pathology of the cardiovascular system.

  12. Neuro-Glial and Systemic Mechanisms of Pathological Responses in Rat Models of Primary Blast Overpressure Compared to “Composite” Blast

    OpenAIRE

    Svetlov, Stanislav I.; Prima, Victor; Glushakova, Olena; Svetlov, Artem; Kirk, Daniel R.; Gutierrez, Hector; Serebruany, Victor L.; Curley, Kenneth C.; Wang, Kevin K. W.; Hayes, Ronald L.

    2012-01-01

    A number of experimental models of blast brain injury have been implemented in rodents and larger animals. However, the variety of blast sources and the complexity of blast wave biophysics have made data on injury mechanisms and biomarkers difficult to analyze and compare. Recently, we showed the importance of rat position toward blast generated by an external shock tube. In this study, we further characterized blast producing moderate traumatic brain injury and defined “composite” blast and ...

  13. Self-Motion Mechanism Of Chained Spherical Grains Cells

    CERN Document Server

    Viridi, Sparisoma

    2013-01-01

    Cells are modeled with spherical grains connected each other. Each cell can shrink and swell by transporting its fluid content to other connected neighbor while still maintaining its density at constant value. As a spherical part of a cell swells it gains more pressure from its surrounding, while shrink state gains less pressure. Pressure difference between these two or more parts of cell will create motion force for the cell. For simplicity, cell is considered to have same density as its environment fluid and connections between parts of cell are virtually accommodated by a spring force. This model is also limited to 2-d case. Influence of parameters to cell motion will be presented. One grain cell shows no motion, while two and more grains cell can perform a motion.

  14. Hip joint pathology

    DEFF Research Database (Denmark)

    Tijssen, M; van Cingel, R E H; de Visser, E;

    2016-01-01

    The purpose of this retrospective cohort study was to (a) describe the clinical presentation of femoroacetabular impingement (FAI) and hip labral pathology; (b) describe the accuracy of patient history and physical tests for FAI and labral pathology as confirmed by hip arthroscopy. Patients (18...... FABER test or a positive AIT and a positive FABER test were the shortest most sensitive combinations. The results of this study point out that in clinical practice absence of groin as main location of pain combined with a negative FABER test or the combination of a negative AIT and a negative FABER test...... are suggested to rule out the diagnosis of symptomatic FAI and/or labral pathology....

  15. Cell Line Derived Multi-Gene Predictor of Pathologic Response to Neoadjuvant Chemotherapy in Breast Cancer: A Validation Study on US Oncology 02-103 Clinical Trial

    Directory of Open Access Journals (Sweden)

    Shen Kui

    2012-11-01

    Full Text Available Abstract Background The purpose of this study is to assess the predictive accuracy of a multi-gene predictor of response to docetaxel, 5-fluorouracil, epirubicin and cyclophosphamide combination chemotherapy on gene expression data from patients who received these drugs as neoadjuvant treatment. Methods Tumor samples were obtained from patients with stage II-III breast cancer before starting neoadjuvant chemotherapy with four cycles of 5-fluorouracil/epirubicin/cyclophosphamide (FEC followed by four cycles of docetaxel/capecitabine (TX on US Oncology clinical trial 02-103. Most patients with HER-2-positive cancer also received trastuzumab (H. The chemotherapy predictor (TFEC-MGP was developed from publicly available gene expression data of 42 breast cancer cell-lines with corresponding in vitro chemotherapy sensitivity results for the four chemotherapy drugs. No predictor was developed for treatment with trastuzumab. The predictive performance of TFEC-MGP in distinguishing cases with pathologic complete response from those with residual disease was evaluated for the FEC/TX and FEC/TX plus H group separately. The area under the receiver-operating characteristic curve (AU-ROC was used as the metric of predictive performance. Genomic predictions were performed blinded to clinical outcome. Results The AU-ROC was 0.70 (95% CI: 0.57-0.82 for the FEC/TX group (n=66 and 0.43 (95% CI: 0.20-0.66 for the FEC/TX plus H group (n=25. Among the patients treated with FEC/TX, the AU-ROC was 0.69 (95% CI: 0.52-0.86 for estrogen receptor (ER-negative (n=28 and it was 0.59 (95% CI: 0.36-0.82 for ER-positive cancers (n=37. ER status was not reported for one patient. Conclusions Our results indicate that the cell line derived 291-probeset genomic predictor of response to FEC/TX combination chemotherapy shows good performance in a blinded validation study, particularly in ER-negative patients.

  16. The Application of Micropipette Aspiration in Molecular Mechanics of Single Cells