Tropomyosin Receptor Kinase A Expression on Merkel Cell Carcinoma Cells.

Science.gov (United States)

Wehkamp, Ulrike; Stern, Sophie; Krüger, Sandra; Hauschild, Axel; Röcken, Christoph; Egberts, Friederike

2017-11-01

Merkel cell carcinoma (MCC) is a malignant neuroendocrine skin tumor frequently associated with the Merkel cell polyomavirus. Immune checkpoint therapy showed remarkable results, although not all patients are responsive to this therapy. Anti-tropomyosin receptor kinase A (TrkA)-targeted treatment has shown promising results in several tumor entities. To determine TrkA expression in MCC as a rationale for potential targeted therapy. This case series study investigated the MCC specimens of 55 patients treated at the Department of Dermatology, University Hospital of Schleswig-Holstein, Kiel, Germany, from January 1, 2005, through December 31, 2015. Thirty-nine of the 55 samples were suitable for further histopathologic examination. Expression of TrkA was explored by immunohistochemical analysis. Diagnosis of MCC was confirmed by staining positive for cytokeratin 20 (CK20) and synaptophysin. Expression of TrkA on the tumor cells. Specimens of 39 patients (21 women and 18 men; mean [SD] age, 75.0 [7.8] years) underwent immunohistochemical investigation. Thirty-eight of 38 specimens expressed CK20 and synaptophysin on the MCC tumor cells (100% expression). Merkel cell polyomavirus was detected in 32 of 38 specimens (84%). Tropomyosin receptor kinase A was found in all 36 evaluable specimens on the tumor cells; 34 (94%) showed a weak and 2 (6%) showed a strong cytoplasmic expression. In addition, strongly positive perinuclear dots were observed in 30 of 36 specimens (83%). Tropomyosin receptor kinase A was expressed on MCC tumor cells in 100% of evaluable specimens. This result may lead to the exploration of new targeted treatment options in MCC, especially for patients who do not respond to anti-programmed cell death protein 1 treatment.

Shrimp Tropomyosin Retains Antibody Reactivity after Exposure to Acidic Conditions

Science.gov (United States)

Although shrimp can be found in certain high acid food matrices, the allergenic capacity of shrimp tropomyosin exposed to low pH condition has not been fully clarified. Thus, a model marinade comprising white vinegar adjusted to different pH was used to determine the effects of acid-induced denatura...

The N-terminal tropomyosin- and actin-binding sites are important for leiomodin 2's function.

Science.gov (United States)

Ly, Thu; Moroz, Natalia; Pappas, Christopher T; Novak, Stefanie M; Tolkatchev, Dmitri; Wooldridge, Dayton; Mayfield, Rachel M; Helms, Gregory; Gregorio, Carol C; Kostyukova, Alla S

2016-08-15

Leiomodin is a potent actin nucleator related to tropomodulin, a capping protein localized at the pointed end of the thin filaments. Mutations in leiomodin-3 are associated with lethal nemaline myopathy in humans, and leiomodin-2-knockout mice present with dilated cardiomyopathy. The arrangement of the N-terminal actin- and tropomyosin-binding sites in leiomodin is contradictory and functionally not well understood. Using one-dimensional nuclear magnetic resonance and the pointed-end actin polymerization assay, we find that leiomodin-2, a major cardiac isoform, has an N-terminal actin-binding site located within residues 43-90. Moreover, for the first time, we obtain evidence that there are additional interactions with actin within residues 124-201. Here we establish that leiomodin interacts with only one tropomyosin molecule, and this is the only site of interaction between leiomodin and tropomyosin. Introduction of mutations in both actin- and tropomyosin-binding sites of leiomodin affected its localization at the pointed ends of the thin filaments in cardiomyocytes. On the basis of our new findings, we propose a model in which leiomodin regulates actin poly-merization dynamics in myocytes by acting as a leaky cap at thin filament pointed ends. © 2016 Ly, Moroz, et al. This article is distributed by The American Society for Cell Biology under license from the author(s). Two months after publication it is available to the public under an Attribution–Noncommercial–Share Alike 3.0 Unported Creative Commons License (http://creativecommons.org/licenses/by-nc-sa/3.0).

Structure of a tropomyosin N-terminal fragment at 0.98 Å resolution

International Nuclear Information System (INIS)

Meshcheryakov, Vladimir A.; Krieger, Inna; Kostyukova, Alla S.; Samatey, Fadel A.

2011-01-01

The crystal structure of the N-terminal fragment of the short nonmuscle α-tropomyosin has been determined at a resolution of 0.98 Å. Tropomyosin (TM) is an elongated two-chain protein that binds along actin filaments. Important binding sites are localized in the N-terminus of tropomyosin. The structure of the N-terminus of the long muscle α-TM has been solved by both NMR and X-ray crystallography. Only the NMR structure of the N-terminus of the short nonmuscle α-TM is available. Here, the crystal structure of the N-terminus of the short nonmuscle α-TM (αTm1bZip) at a resolution of 0.98 Å is reported, which was solved from crystals belonging to space group P3 1 with unit-cell parameters a = b = 33.00, c = 52.03 Å, α = β = 90, γ = 120°. The first five N-terminal residues are flexible and residues 6–35 form an α-helical coiled coil. The overall fold and the secondary structure of the crystal structure of αTM1bZip are highly similar to the NMR structure and the atomic coordinates of the corresponding C α atoms between the two structures superimpose with a root-mean-square deviation of 0.60 Å. The crystal structure validates the NMR structure, with the positions of the side chains being determined precisely in our structure

Structure of a tropomyosin N-terminal fragment at 0.98 Å resolution

Energy Technology Data Exchange (ETDEWEB)

Meshcheryakov, Vladimir A. [Okinawa Institute of Science and Technology, Okinawa (Japan); Krieger, Inna [Texas A& M University, College Station, Texas (United States); Kostyukova, Alla S. [Robert Wood Johnson Medical School, Piscataway, New Jersey (United States); Samatey, Fadel A., E-mail: f.a.samatey@oist.jp [Okinawa Institute of Science and Technology, Okinawa (Japan)

2011-09-01

The crystal structure of the N-terminal fragment of the short nonmuscle α-tropomyosin has been determined at a resolution of 0.98 Å. Tropomyosin (TM) is an elongated two-chain protein that binds along actin filaments. Important binding sites are localized in the N-terminus of tropomyosin. The structure of the N-terminus of the long muscle α-TM has been solved by both NMR and X-ray crystallography. Only the NMR structure of the N-terminus of the short nonmuscle α-TM is available. Here, the crystal structure of the N-terminus of the short nonmuscle α-TM (αTm1bZip) at a resolution of 0.98 Å is reported, which was solved from crystals belonging to space group P3{sub 1} with unit-cell parameters a = b = 33.00, c = 52.03 Å, α = β = 90, γ = 120°. The first five N-terminal residues are flexible and residues 6–35 form an α-helical coiled coil. The overall fold and the secondary structure of the crystal structure of αTM1bZip are highly similar to the NMR structure and the atomic coordinates of the corresponding C{sup α} atoms between the two structures superimpose with a root-mean-square deviation of 0.60 Å. The crystal structure validates the NMR structure, with the positions of the side chains being determined precisely in our structure.

Guard Cell and Tropomyosin Inspired Chemical Sensor

Directory of Open Access Journals (Sweden)

Jacquelyn K.S. Nagel

2013-10-01

Full Text Available Sensors are an integral part of many engineered products and systems. Biological inspiration has the potential to improve current sensor designs as well as inspire innovative ones. This paper presents the design of an innovative, biologically-inspired chemical sensor that performs “up-front” processing through mechanical means. Inspiration from the physiology (function of the guard cell coupled with the morphology (form and physiology of tropomyosin resulted in two concept variants for the chemical sensor. Applications of the sensor design include environmental monitoring of harmful gases, and a non-invasive approach to detect illnesses including diabetes, liver disease, and cancer on the breath.

Tissue bioengineering and artificial organs.

Science.gov (United States)

Llames, Sara; García, Eva; Otero Hernández, Jesús; Meana, Alvaro

2012-01-01

The scarcity of organs and tissues for transplant and the need of immunosuppressive drugs to avoid rejection constitute two reasons that justify organ and tissue production in the laboratory. Tissue engineering based tissues (TE) could allow to regenerate the whole organ from a fragment or even to produce several organs from an organ donor for grafting purposes. TE is based in: (1) the ex vivo expansion of cells, (2) the seeding of these expanded cells in tridimensional structures that mimic physiological conditions and, (3) grafting the prototype. In order to graft big structures it is necessary that the organ or tissue produced "ex vivo" bears a vascular tree to ensure the nutrition of its deep layers. At present, no technology has been developed to provide this vascular tree to TE derived products. Thus, these tissues must be thin enough to acquire nutrients during the first days by diffusion from surrounding tissues. This fact constitutes nowadays the greatest limitation of technologies for organ development in the laboratory.In this chapter, all these problems and their possible solutions are commented. Also, the present status of TE techniques in the regeneration of different organ systems is reviewed.

Influence of Thermal Treatment on the Characteristics of Major Oyster Allergen Cra g 1 (Tropomyosin).

Science.gov (United States)

Fang, Lei; Li, Guoming; Gu, Ruizeng; Cai, Muyi; Lu, Jun

2018-04-15

Shellfish, including oysters, often cause allergic reactions in adults. Thermal treatment is one of the most common technologies to deal with seafood, which may affect biological properties. The aim of this work was to evaluate the impact of heating on conformation and potential allergenicity of oyster-derived tropomyosin (Cra g 1). SDS-PAGE showed that there was an apparent band at 35KD of raw tropomyosin after purification and more significant polymers appeared in heated protein. Interestingly, the obviously changes in the intensity of CD signal and ANS-binding fluorescence were observed especially in the case of roasted form, which was associated with an increase in antibody reactivity. The degree of IgE binding of this treatment was demonstrated in the order roasted>boiled > raw. Furthermore, sequence alignment and amino acid composition revealed that Cra g 1 shared relatively high homology to tropomyosins from other shellfish and was abundant in lysine that was apt to be modified by reducing sugars during heating. Heated Cra g 1 produces higher IgE reactivity than raw one, owing to denaturation and formation of polymers. These findings will benefit more diagnosis and management of potential allergenicity due to shellfish. This article is protected by copyright. All rights reserved.

Tropomyosin-1, a Novel Class II Tumor-Suppressor and a Biomarker of Human Breast Cancer

National Research Council Canada - National Science Library

Prasad, Gaddamanugu

2002-01-01

.... Downregulation of microfilament-associated proteins, such as tropomyosins (TMs) is hypothesized to result in the formation of functionally aberrant microfilaments, thus contributing to the manifestation of the malignant cells...

Chinese herbal formula Tongluo Jiunao injection protects against cerebral ischemia by activating neurotrophin 3/tropomyosin-related kinase C pathway

Directory of Open Access Journals (Sweden)

Peiman Alesheikh

2015-01-01

Full Text Available The Chinese herbal formula Tongluo Jiunao, containing the active components Panax notoginseng and Gardenia jasminoides, has recently been patented and is in use clinically. It is known to be neuroprotective in cerebral ischemia, but the underlying pathway remains poorly understood. In the present study, we established a rat model of cerebral ischemia by occlusion of the middle cerebral artery, and administered Tongluo Jiunao, a positive control (Xuesai Tong, containing Panax notoginseng or saline intraperitoneally to investigate the pathway involved in the action of Tongluo Jiunao injection. 2,3,5-Triphenyltetrazolium chloride (TTC staining showed that the cerebral infarct area was significantly smaller in model rats that received Tongluo Jiunao than in those that received saline. Enzyme-linked immunosorbent assay revealed significantly greater expression of neurotrophin 3 and growth-associated protein 43 in ischemic cerebral tissue, and serum levels of neurotrophin 3, in the Tongluo Jiunao group than in the saline group. The reverse transcription polymerase chain reaction and immunohistochemical staining showed that after treatment with Tongluo Jiunao or Xuesai Tong, tropomyosin-related kinase C gene expression and immunoreactivity were significantly elevated compared with saline, with the greatest expression observed after Tongluo Jiunao treatment. These findings suggest that Tongluo Jiunao injection exerts a neuroprotective effect in rats with cerebral ischemia by activating the neurotrophin 3/tropomyosin-related kinase C pathway.

Tus-Ter-lock immuno-PCR assays for the sensitive detection of tropomyosin-specific IgE antibodies.

Science.gov (United States)

Johnston, Elecia B; Kamath, Sandip D; Lopata, Andreas L; Schaeffer, Patrick M

2014-02-01

The increasing prevalence of food allergies requires development of specific and sensitive tests capable of identifying the allergen responsible for the disease. The development of serologic tests that can detect specific IgE antibodies to allergenic proteins would, therefore, be highly received. Here we present two new quantitative immuno-PCR assays for the sensitive detection of antibodies specific to the shrimp allergen tropomyosin. Both assays are based on the self-assembling Tus-Ter-lock protein-DNA conjugation system. Significantly elevated levels of tropomyosin-specific IgE were detected in sera from patients allergic to shrimp. This is the first time an allergenic protein has been fused with Tus to enable specific IgE antibody detection in human sera by quantitative immuno-PCR.

3D Bioprinting of Tissue/Organ Models.

Science.gov (United States)

Pati, Falguni; Gantelius, Jesper; Svahn, Helene Andersson

2016-04-04

In vitro tissue/organ models are useful platforms that can facilitate systematic, repetitive, and quantitative investigations of drugs/chemicals. The primary objective when developing tissue/organ models is to reproduce physiologically relevant functions that typically require complex culture systems. Bioprinting offers exciting prospects for constructing 3D tissue/organ models, as it enables the reproducible, automated production of complex living tissues. Bioprinted tissues/organs may prove useful for screening novel compounds or predicting toxicity, as the spatial and chemical complexity inherent to native tissues/organs can be recreated. In this Review, we highlight the importance of developing 3D in vitro tissue/organ models by 3D bioprinting techniques, characterization of these models for evaluating their resemblance to native tissue, and their application in the prioritization of lead candidates, toxicity testing, and as disease/tumor models. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Aging changes in organs - tissue - cells

Science.gov (United States)

... and structure to the skin and internal organs. Epithelial tissue provides a covering for deeper body layers. The ... such as the gastrointestinal system, are made of epithelial tissue. Muscle tissue includes three types of tissue: Striated ...

Phosphorylation of Tropomyosin Extends Cooperative Binding of Myosin Beyond a Single Regulatory Unit

OpenAIRE

Rao, Vijay S.; Marongelli, Ellisha N.; Guilford, William H.

2009-01-01

Tropomyosin (Tm) is one of the major phosphoproteins comprising the thin filament of muscle. However, the specific role of Tm phosphorylation in modulating the mechanics of actomyosin interaction has not been determined. Here we show that Tm phosphorylation is necessary for long-range cooperative activation of myosin binding. We used a novel optical trapping assay to measure the isometric stall force of an ensemble of myosin molecules moving actin filaments reconstituted with either natively ...

Expression of various sarcomeric tropomyosin isoforms in equine striated muscles

Directory of Open Access Journals (Sweden)

Syamalima Dube

2017-06-01

Full Text Available In order to better understand the training and athletic activity of horses, we must have complete understanding of the isoform diversity of various myofibrillar protein genes like tropomyosin. Tropomyosin (TPM, a coiled-coil dimeric protein, is a component of thin filament in striated muscles. In mammals, four TPM genes (TPM1, TPM2, TPM3, and TPM4 generate a multitude of TPM isoforms via alternate splicing and/or using different promoters. Unfortunately, our knowledge of TPM isoform diversity in the horse is very limited. Hence, we undertook a comprehensive exploratory study of various TPM isoforms from horse heart and skeletal muscle. We have cloned and sequenced two sarcomeric isoforms of the TPM1 gene called TPM1α and TPM1κ, one sarcomeric isoform of the TPM2 and one of the TPM3 gene, TPM2α and TPM3α respectively. By qRT-PCR using both relative expression and copy number, we have shown that TPM1α expression compared to TPM1κ is very high in heart. On the other hand, the expression of TPM1α is higher in skeletal muscle compared to heart. Further, the expression of TPM2α and TPM3α are higher in skeletal muscle compared to heart. Using western blot analyses with CH1 monoclonal antibody we have shown the high expression levels of sarcomeric TPM proteins in cardiac and skeletal muscle. Due to the paucity of isoform specific antibodies we cannot specifically detect the expression of TPM1κ in horse striated muscle. To the best of our knowledge this is the very first report on the characterization of sarcmeric TPMs in horse striated muscle.

3D Printing of Personalized Organs and Tissues

Science.gov (United States)

Ye, Kaiming

2015-03-01

Authors: Kaiming Ye and Sha Jin, Department of Biomedical Engineering, Watson School of Engineering and Applied Science, Binghamton University, State University of New York, Binghamton, NY 13902-6000 Abstract: Creation of highly organized multicellular constructs, including tissues and organs or organoids, will revolutionize tissue engineering and regenerative medicine. The development of these technologies will enable the production of individualized organs or tissues for patient-tailored organ transplantation or cell-based therapy. For instance, a patient with damaged myocardial tissues due to an ischemic event can receive a myocardial transplant generated using the patient's own induced pluripotent stem cells (iPSCs). Likewise, a type-1 diabetic patient can be treated with lab-generated islets to restore his or her physiological insulin secretion capability. These lab-produced, high order tissues or organs can also serve as disease models for pathophysiological study and drug screening. The remarkable advances in stem cell biology, tissue engineering, microfabrication, and materials science in the last decade suggest the feasibility of generating these tissues and organoids in the laboratory. Nevertheless, major challenges still exist. One of the critical challenges that we still face today is the difficulty in constructing or fabricating multicellular assemblies that recapitulate in vivo microenvironments essential for controlling cell proliferation, migration, differentiation, maturation and assembly into a biologically functional tissue or organoid structure. These challenges can be addressed through developing 3D organ and tissue printing which enables organizing and assembling cells into desired tissue and organ structures. We have shown that human pluripotent stem cells differentiated in 3D environments are mature and possess high degree of biological function necessary for them to function in vivo.

Tissue and Organ 3D Bioprinting.

Science.gov (United States)

Xia, Zengmin; Jin, Sha; Ye, Kaiming

2018-02-01

Three-dimensional (3D) bioprinting enables the creation of tissue constructs with heterogeneous compositions and complex architectures. It was initially used for preparing scaffolds for bone tissue engineering. It has recently been adopted to create living tissues, such as cartilage, skin, and heart valve. To facilitate vascularization, hollow channels have been created in the hydrogels by 3D bioprinting. This review discusses the state of the art of the technology, along with a broad range of biomaterials used for 3D bioprinting. It provides an update on recent developments in bioprinting and its applications. 3D bioprinting has profound impacts on biomedical research and industry. It offers a new way to industrialize tissue biofabrication. It has great potential for regenerating tissues and organs to overcome the shortage of organ transplantation.

Trend Analysis of Organ and Tissue Donation for Transplantation.

Science.gov (United States)

Dos Santos, M J; Leal de Moraes, E; Santini Martins, M; Carlos de Almeida, E; Borges de Barros E Silva, L; Urias, V; Silvano Corrêa Pacheco Furtado, M C; Brito Nunes, Á; El Hage, S

2018-03-01

The goal of this study was to identify the tendency toward donations of tissue and organs from donors with brain death between 2001 and 2016 as registered by an organ procurement organization in São Paulo City. This quantitative, retrospective, exploratory study encompassed all Tissue and Organ Donation Terms signed between 2001 and 2016. A logistic regression model was applied to verify whether there was an upward or downward trend in donation. After statistical analysis, a significant change trend was identified in skin, bones, valve, vessel, heart, lung, and pancreas donations, indicating an increase in the donation rate through the years. The donation rate did not show changes over the years for donations of liver, kidneys, and corneas. The decision-making process regarding organ and tissue donation is restricted not only to the dilemma of whether to donate but another question then arises as well: which organs and tissues are to be donated? The discrepancy between the authorization for organ donation and the authorization for tissue donation, as well as the option for one or another organ and/or tissue, must be thoroughly examined because these factors directly affect the number of transplants and acquirements effectively accomplished. These factors may be related to explaining to one's relatives aspects of the surgery, body reassembling, and usage of such organs and/or tissues. They may also be related to the lack of knowledge concerning organ donation and the symbolism represented by the organ and/or tissue, among other factors. Copyright © 2018 Elsevier Inc. All rights reserved.

Autoimmunity to Tropomyosin-Specific Peptides Induced by Mycobacterium leprae in Leprosy Patients: Identification of Mimicking Proteins

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Itu Singh

2018-04-01

-binding subunit of M. leprae. We found four mimicking epitopes between these sequences.ConclusionThese data suggest that these mimicking proteins tropomyosin and ATP-dependent Clp protease ATP-binding subunit of M. leprae or more precisely mimicking epitopes (four B cell epitopes might be responsible for extensive tissue damage during type1 reaction in leprosy.

Regeneration of Tissues and Organs Using Autologous Cells

Energy Technology Data Exchange (ETDEWEB)

Anthony Atala

2010-04-28

The Joint Commission for Health Care Organizations recently declared the shortage of transplantable organs and tissues a public health crisis. As such, there is about one death every 30 seconds due to organ failure. Complications and rejection are still significant albeit underappreciated problems. It is often overlooked that organ transplantation results in the patient being placed on an immune suppression regimen that will ultimate shorten their life span. Patients facing reconstruction often find that surgery is difficult or impossible due to the shortage of healthy autologous tissue. In many cases, autografting is a compromise between the condition and the cure that can result in substantial diminution of quality of life. The national cost of caring for persons who might benefit from engineered tissues or organs has reached $600 billion annually. Autologous tissue technologies have been developed as an alternative to transplantation or reconstructive surgery. Autologous tissues derived from the patient's own cells are capable of correcting numerous pathologies and injuries. The use of autologous cells eliminates the risks of rejection and immunological reactions, drastically reduces the time that patients must wait for lifesaving surgery, and negates the need for autologous tissue harvest, thereby eliminating the associated morbidities. In fact, the use of autologous tissues to create functional organs is one of the most important and groundbreaking steps ever taken in medicine. Although the basic premise of creating tissues in the laboratory has progressed dramatically, only a limited number of tissue developments have reached the patients to date. This is due, in part, to the several major technological challenges that require solutions. To that end, we have been in pursuit of more efficient ways to expand cells in vitro, methods to improve vascular support so that relevant volumes of engineered tissues can be grown, and constructs that can mimic the

Suppression of expression of muscle-associated proteins by PPARα in brown adipose tissue

International Nuclear Information System (INIS)

Tong, Yuhong; Hara, Atsushi; Komatsu, Makiko; Tanaka, Naoki; Kamijo, Yuji; Gonzalez, Frank J.; Aoyama, Toshifumi

2005-01-01

Peroxisome proliferator-activated receptor α (PPARα) belongs to the steroid/nuclear receptor superfamily. Two-dimensional (2D) SDS-PAGE analysis of brown adipose tissue (BAT) unexpectedly revealed six spots that were present only in PPARα-null mice. Proteomic analysis indicated that these proteins were tropomyosin-1 α chain, tropomyosin β chain, myosin regulatory light chain 2, myosin light chain 3, and parvalbumin α. Analyses of mRNA have revealed that PPARα suppressed the genes encoding these proteins in a synchronous manner in adult wild-type mice. Histological and physiological analyses of BAT showed in adult wild-type mice, a marked suppression of BAT growth concurrent with a prominent decrease in lipolytic and thermogenesis activities. These results suggest that in adult mice, PPARα functions to suppress the expression of the proteins that may be involved in the architecture of BAT, and thus may function in keeping BAT in a quiescent state

Tissue strands as "bioink" for scale-up organ printing.

Science.gov (United States)

Yu, Yin; Ozbolat, Ibrahim T

2014-01-01

Organ printing, takes tissue spheroids as building blocks together with additive manufacturing technique to engineer tissue or organ replacement parts. Although a wide array of cell aggregation techniques has been investigated, and gained noticeable success, the application of tissue spheroids for scale-up tissue fabrication is still worth investigation. In this paper, we introduce a new micro-fabrication technique to create tissue strands at the scale of 500-700μm as a "bioink" for future robotic tissue printing. Printable alginate micro-conduits are used as semi-permeable capsules for tissue strand fabrication. Mouse insulinoma beta TC3 cell tissue strands were formed upon 4 days post fabrication with reasonable mechanical strength, high cell viability close to 90%, and tissue specific markers expression. Fusion was readily observed between strands when placing them together as early as 24h. Also, tissue strands were deposited with human umbilical vein smooth muscle cells (HUVSMCs) vascular conduits together to fabricated miniature pancreatic tissue analog. Our study provided a novel technique using tissue strands as "bioink" for scale-up bioprinting of tissues or organs.

Self-Organization and the Self-Assembling Process in Tissue Engineering

Science.gov (United States)

Eswaramoorthy, Rajalakshmanan; Hadidi, Pasha; Hu, Jerry C.

2015-01-01

In recent years, the tissue engineering paradigm has shifted to include a new and growing subfield of scaffoldless techniques which generate self-organizing and self-assembling tissues. This review aims to provide a cogent description of this relatively new research area, with special emphasis on applications toward clinical use and research models. Particular emphasis is placed on providing clear definitions of self-organization and the self-assembling process, as delineated from other scaffoldless techniques in tissue engineering and regenerative medicine. Significantly, during formation, self-organizing and self-assembling tissues display biological processes similar to those that occur in vivo. These help lead to the recapitulation of native tissue morphological structure and organization. Notably, functional properties of these tissues also approach native tissue values; some of these engineered tissues are already in clinical trials. This review aims to provide a cohesive summary of work in this field, and to highlight the potential of self-organization and the self-assembling process to provide cogent solutions to current intractable problems in tissue engineering. PMID:23701238

Functional evaluation of artificial skeletal muscle tissue constructs fabricated by a magnetic force-based tissue engineering technique.

Science.gov (United States)

Yamamoto, Yasunori; Ito, Akira; Fujita, Hideaki; Nagamori, Eiji; Kawabe, Yoshinori; Kamihira, Masamichi

2011-01-01

Skeletal muscle tissue engineering is currently applied in a variety of research fields, including regenerative medicine, drug screening, and bioactuator development, all of which require the fabrication of biomimic and functional skeletal muscle tissues. In the present study, magnetite cationic liposomes were used to magnetically label C2C12 myoblast cells for the construction of three-dimensional artificial skeletal muscle tissues by an applied magnetic force. Skeletal muscle functions, such as biochemical and contractile properties, were evaluated for the artificial tissue constructs. Histological studies revealed that elongated and multinucleated myotubes were observed within the tissue. Expression of muscle-specific markers, such as myogenin, myosin heavy chain and tropomyosin, were detected in the tissue constructs by western blot analysis. Further, creatine kinase activity increased during differentiation. In response to electric pulses, the artificial tissue constructs contracted to generate a physical force (the maximum twitch force, 33.2 μN [1.06 mN/mm2]). Rheobase and chronaxie of the tissue were determined as 4.45 V and 0.72 ms, respectively. These results indicate that the artificial skeletal muscle tissue constructs fabricated in this study were physiologically functional and the data obtained for the evaluation of their functional properties may provide useful information for future skeletal muscle tissue engineering studies.

3D Bioprinting Technologies for Hard Tissue and Organ Engineering

Science.gov (United States)

Wang, Xiaohong; Ao, Qiang; Tian, Xiaohong; Fan, Jun; Wei, Yujun; Hou, Weijian; Tong, Hao; Bai, Shuling

2016-01-01

Hard tissues and organs, including the bones, teeth and cartilage, are the most extensively exploited and rapidly developed areas in regenerative medicine field. One prominent character of hard tissues and organs is that their extracellular matrices mineralize to withstand weight and pressure. Over the last two decades, a wide variety of 3D printing technologies have been adapted to hard tissue and organ engineering. These 3D printing technologies have been defined as 3D bioprinting. Especially for hard organ regeneration, a series of new theories, strategies and protocols have been proposed. Some of the technologies have been applied in medical therapies with some successes. Each of the technologies has pros and cons in hard tissue and organ engineering. In this review, we summarize the advantages and disadvantages of the historical available innovative 3D bioprinting technologies for used as special tools for hard tissue and organ engineering. PMID:28773924

3D Bioprinting Technologies for Hard Tissue and Organ Engineering

Directory of Open Access Journals (Sweden)

Xiaohong Wang

2016-09-01

Full Text Available Hard tissues and organs, including the bones, teeth and cartilage, are the most extensively exploited and rapidly developed areas in regenerative medicine field. One prominent character of hard tissues and organs is that their extracellular matrices mineralize to withstand weight and pressure. Over the last two decades, a wide variety of 3D printing technologies have been adapted to hard tissue and organ engineering. These 3D printing technologies have been defined as 3D bioprinting. Especially for hard organ regeneration, a series of new theories, strategies and protocols have been proposed. Some of the technologies have been applied in medical therapies with some successes. Each of the technologies has pros and cons in hard tissue and organ engineering. In this review, we summarize the advantages and disadvantages of the historical available innovative 3D bioprinting technologies for used as special tools for hard tissue and organ engineering.

3D Bioprinting Technologies for Hard Tissue and Organ Engineering.

Science.gov (United States)

Wang, Xiaohong; Ao, Qiang; Tian, Xiaohong; Fan, Jun; Wei, Yujun; Hou, Weijian; Tong, Hao; Bai, Shuling

2016-09-27

Hard tissues and organs, including the bones, teeth and cartilage, are the most extensively exploited and rapidly developed areas in regenerative medicine field. One prominent character of hard tissues and organs is that their extracellular matrices mineralize to withstand weight and pressure. Over the last two decades, a wide variety of 3D printing technologies have been adapted to hard tissue and organ engineering. These 3D printing technologies have been defined as 3D bioprinting. Especially for hard organ regeneration, a series of new theories, strategies and protocols have been proposed. Some of the technologies have been applied in medical therapies with some successes. Each of the technologies has pros and cons in hard tissue and organ engineering. In this review, we summarize the advantages and disadvantages of the historical available innovative 3D bioprinting technologies for used as special tools for hard tissue and organ engineering.

Tropomyosin 2 heterozygous knockout in mice using CRISPR-Cas9 system displays the inhibition of injury-induced epithelial-mesenchymal transition, and lens opacity

Science.gov (United States)

Shibata, Teppei; Shibata, Shinsuke; Ishigaki, Yasuhito; Kiyokawa, Etsuko; Ikawa, Masahito; Singh, Dhirendra P.; Sasaki, Hiroshi; Kubo, Eri

2018-01-01

The process of epithelial–mesenchymal transition (EMT) of lens epithelial cells (LECs) after cataract surgery contributes to tissue fibrosis, wound healing and lens regeneration via a mechanism not yet fully understood. Here, we show that tropomyosin 2 (Tpm2) plays a critical role in wound healing and lens aging. Posterior capsular opacification (PCO) after lens extraction surgery was accompanied by elevated expression of Tpm2. Tpm2 heterozygous knockout mice, generated via the clustered regularly interspaced short palindromic repeat/ Cas9 (CRISPR/Cas9) system showed promoted progression of cataract with age. Further, injury-induced EMT of the mouse lens epithelium, as evaluated histologically and by the expression patterns of Tpm1 and Tpm2, was attenuated in the absence of Tpm2. In conclusion, Tpm2 may be important in maintaining lens physiology and morphology. However, Tpm2 is involved in the progression of EMT during the wound healing process of mouse LECs, suggesting that inhibition of Tpm2 may suppress PCO. PMID:29510160

Cytoskeletal Tropomyosin Tm5NM1 Is Required for Normal Excitation–Contraction Coupling in Skeletal Muscle

OpenAIRE

Vlahovich, Nicole; Kee, Anthony J.; Van der Poel, Chris; Kettle, Emma; Hernandez-Deviez, Delia; Lucas, Christine; Lynch, Gordon S.; Parton, Robert G.; Gunning, Peter W.; Hardeman, Edna C.

2009-01-01

The functional diversity of the actin microfilaments relies in part on the actin binding protein tropomyosin (Tm). The muscle-specific Tms regulate actin-myosin interactions and hence contraction. However, there is less known about the roles of the numerous cytoskeletal isoforms. We have shown previously that a cytoskeletal Tm, Tm5NM1, defines a Z-line adjacent cytoskeleton in skeletal muscle. Recently, we identified a second cytoskeletal Tm in this region, Tm4. Here we show that Tm4 and Tm5N...

3D Bioprinting Technologies for Hard Tissue and Organ Engineering

OpenAIRE

Wang, Xiaohong; Ao, Qiang; Tian, Xiaohong; Fan, Jun; Wei, Yujun; Hou, Weijian; Tong, Hao; Bai, Shuling

2016-01-01

Hard tissues and organs, including the bones, teeth and cartilage, are the most extensively exploited and rapidly developed areas in regenerative medicine field. One prominent character of hard tissues and organs is that their extracellular matrices mineralize to withstand weight and pressure. Over the last two decades, a wide variety of 3D printing technologies have been adapted to hard tissue and organ engineering. These 3D printing technologies have been defined as 3D bioprinting. Especial...

Tissue and organ regeneration in adults extension of the paradigm to several organs

CERN Document Server

Yannas, Ioannis V

2015-01-01

This textbook describes the basic principles of induced organ regeneration in skin and peripheral nerves and extends the original successful paradigm to other organs. A set of trans-organ rules is established and its use in regeneration of several organs is illustrated from the works of several independent investigators who worked with a variety of organs, such as the lung, the bladder, and the Achilles tendon, using collagen-based scaffolds somewhat similar to the original one. These critical medical treatments fill the clinical need that is not met by organ transplantation. New to this second edition: New information extending the paradigm of tissue regeneration from organ regeneration in skin and peripheral nerves to other organs Guidelines, known as trans-organ rules, are described for the first time for extending this unique medical treatment to organs of several medical specialties The work serves as a comprehensive text and reference for students and practitioners of tissue engineering  

The necessity of strengthening the cooperation between tissue banks and organ transplant organizations at national, regional, and international levels.

Science.gov (United States)

Morales Pedraza, Jorge

2013-12-01

The donation of tissues and organs increases significantly when tissue banks and organ transplant organizations work together in the procurement of organs and tissues at donor sources (hospitals, coroners system, organ procurement agencies, and funeral homes, among others). To achieve this important goal, national competent health authorities should considered the establishment of a mechanism that promote the widest possible cooperation between tissue banks and organ transplant organizations with hospitals, research medical institutions, universities, and other medical institutions and facilities. One of the issues that can facilitate this cooperation is the establishment of a coding and traceability system that could identify all tissues and organs used in transplant activities carried out in any country. The promotion of national, regional, and international cooperation between tissue banks and organ transplant organizations would enable the sharing of relevant information that could be important for medical practice and scientific studies carried out by many countries, particularly for those countries with a weak health care system.

Ethical issues in organ and tissue transplantation.

Science.gov (United States)

Abouna, George M

2003-12-01

Clinical organ transplantation provides a way of giving the gift of life to patients with terminal failure of vital organs, which requires the participation of other fellow human beings and of society by donating organs from deceased or living individuals. The increasing incidence of vital organ failure and the inadequate supply of organs, especially from cadavers, has created a wide gap between organ supply and organ demand, which has resulted in very long waiting times to receive an organ as well as an increasing number of deaths while waiting. These events have raised many ethical, moral and societal issues regarding supply, the methods of organ allocation the use of living donors as volunteers including minors. It has also led to the practice of organ sale by entrepreneurs for financial gains in some parts the world through exploitation of the poor, for the benefit of the wealthy. The current advances in immunology and tissue engineering and the use of animal organs, xenotransplantation, while offering very promising solutions to many of these problems, also raise additional ethical and medical issues, which must be considered by the medical profession as well as society. This review deals with the ethical and moral issues generated by the current advances in organ transplantation, the problem of organ supply versus organ demand and the appropriate allocation of available organs. It deals with the risks and benefits of organ donation from living donors, the appropriate and acceptable methods to increase organ donation from the deceased through the adoption of the principle of 'presumed consent', the right methods of providing acceptable appreciation and compensation for the family of the deceased as well as volunteer and altruistic donors, and the duties and responsibilities of the medical profession and society to help fellow humans. The review also deals with the appropriate and ethically acceptable ways of utilizing the recent advances of stem cell

3D Bioprinting for Tissue and Organ Fabrication.

Science.gov (United States)

Zhang, Yu Shrike; Yue, Kan; Aleman, Julio; Moghaddam, Kamyar Mollazadeh; Bakht, Syeda Mahwish; Yang, Jingzhou; Jia, Weitao; Dell'Erba, Valeria; Assawes, Pribpandao; Shin, Su Ryon; Dokmeci, Mehmet Remzi; Oklu, Rahmi; Khademhosseini, Ali

2017-01-01

The field of regenerative medicine has progressed tremendously over the past few decades in its ability to fabricate functional tissue substitutes. Conventional approaches based on scaffolding and microengineering are limited in their capacity of producing tissue constructs with precise biomimetic properties. Three-dimensional (3D) bioprinting technology, on the other hand, promises to bridge the divergence between artificially engineered tissue constructs and native tissues. In a sense, 3D bioprinting offers unprecedented versatility to co-deliver cells and biomaterials with precise control over their compositions, spatial distributions, and architectural accuracy, therefore achieving detailed or even personalized recapitulation of the fine shape, structure, and architecture of target tissues and organs. Here we briefly describe recent progresses of 3D bioprinting technology and associated bioinks suitable for the printing process. We then focus on the applications of this technology in fabrication of biomimetic constructs of several representative tissues and organs, including blood vessel, heart, liver, and cartilage. We finally conclude with future challenges in 3D bioprinting as well as potential solutions for further development.

3D Bioprinting for Tissue and Organ Fabrication

Science.gov (United States)

Zhang, Yu Shrike; Yang, Jingzhou; Jia, Weitao; Dell’Erba, Valeria; Assawes, Pribpandao; Shin, Su Ryon; Dokmeci, Mehmet Remzi; Oklu, Rahmi; Khademhosseini, Ali

2016-01-01

The field of regenerative medicine has progressed tremendously over the past few decades in its ability to fabricate functional tissue substitutes. Conventional approaches based on scaffolding and microengineering are limited in their capacity of producing tissue constructs with precise biomimetic properties. Three-dimensional (3D) bioprinting technology, on the other hand, promises to bridge the divergence between artificially engineered tissue constructs and native tissues. In a sense, 3D bioprinting offers unprecedented versatility to co-deliver cells and biomaterials with precise control over their compositions, spatial distributions, and architectural accuracy, therefore achieving detailed or even personalized recapitulation of the fine shape, structure, and architecture of target tissues and organs. Here we briefly describe recent progresses of 3D bioprinting technology and associated bioinks suitable for the printing process. We then focus on the applications of this technology in fabrication of biomimetic constructs of several representative tissues and organs, including blood vessel, heart, liver, and cartilage. We finally conclude with future challenges in 3D bioprinting as well as potential solutions for further development. PMID:27126775

Adipose tissue as an endocrine organ.

Science.gov (United States)

McGown, Christine; Birerdinc, Aybike; Younossi, Zobair M

2014-02-01

Obesity is one of the most important health challenges faced by developed countries and is increasingly affecting adolescents and children. Obesity is also a considerable risk factor for the development of numerous other chronic diseases, such as insulin resistance, type 2 diabetes, heart disease and nonalcoholic fatty liver disease. The epidemic proportions of obesity and its numerous comorbidities are bringing into focus the highly complex and metabolically active adipose tissue. Adipose tissue is increasingly being considered as a functional endocrine organ. This article discusses the endocrine effects of adipose tissue during obesity and the systemic impact of this signaling. Copyright © 2014 Elsevier Inc. All rights reserved.

Modularity in developmental biology and artificial organs: a missing concept in tissue engineering.

Science.gov (United States)

Lenas, Petros; Luyten, Frank P; Doblare, Manuel; Nicodemou-Lena, Eleni; Lanzara, Andreina Elena

2011-06-01

Tissue engineering is reviving itself, adopting the concept of biomimetics of in vivo tissue development. A basic concept of developmental biology is the modularity of the tissue architecture according to which intermediates in tissue development constitute semiautonomous entities. Both engineering and nature have chosen the modular architecture to optimize the product or organism development and evolution. Bioartificial tissues do not have a modular architecture. On the contrary, artificial organs of modular architecture have been already developed in the field of artificial organs. Therefore the conceptual support of tissue engineering by the field of artificial organs becomes critical in its new endeavor of recapitulating in vitro the in vivo tissue development. © 2011, Copyright the Authors. Artificial Organs © 2011, International Center for Artificial Organs and Transplantation and Wiley Periodicals, Inc.

Tissue clearing for confocal imaging of native and bio-artificial skeletal muscle.

Science.gov (United States)

Decroix, L; Van Muylder, V; Desender, L; Sampaolesi, M; Thorrez, L

2015-01-01

Novel clearing techniques have revolutionized three-dimensional confocal imaging of the brain without the need for physical tissue sectioning. We evaluated three clearing methods, ScaleA2, Clear(T2), and 3DISCO for visualizing native and tissue engineered muscle by confocal microscopy. We found that Clear(T2) treatment improved the depth of visualization of immunohistochemical staining slightly, but did not improve depth of visualization of endogenous green fluorescent protein (GFP). ScaleA2 preserved endogenous GFP signal better and permitted significantly deeper GFP imaging, but it was incompatible with tropomyosin immunohistochemical staining. 3DISCO treatment preserved both endogenous GFP and immunohistochemical staining, and permitted significantly deeper imaging. Clearing time for the 3DISCO procedure is short compared to ScaleA2 and Clear(T2). We suggest that 3DISCO is the preferable clearing method for native and tissue engineered skeletal muscle tissue.

Tropomyosin and Actin Identified as Major Allergens of the Carpet Clam (Paphia textile and the Effect of Cooking on Their Allergenicity

Directory of Open Access Journals (Sweden)

Zailatul Hani Mohamad Yadzir

2015-01-01

Full Text Available Objectives. To identify the major allergenic proteins of clam (Paphia textile and to investigate the effect of different cooking methods on the allergenicity of these identified proteins. Methods. Clam protein extracts were separated by denaturing polyacrylamide gel electrophoresis. IgE reactive proteins were then analyzed by immunoblotting with sera from patients with positive skin prick tests (SPT to the raw clam extract. Mass spectrometry was used to identify the major allergenic proteins of this clam. Results. Raw extract showed 12 protein bands (18–150 kDa. In contrast, fewer protein bands were seen in the boiled extract; those ranging from 40 to 150 kDa were denatured. The protein profiles were similarly altered by frying or roasting. The immunoblots of raw and boiled extracts yielded 10 and 2 IgE-binding proteins, respectively. The fried and roasted extracts showed only a single IgE-binding protein at 37 kDa. Mass spectrometry analysis of the 37 and 42 kDa major allergens indicated that these spots were tropomyosin and actin, respectively. Conclusion. The two major allergens of Paphia textile were identified as the thermostable tropomyosin and a new thermolabile allergen actin.

Bioprinting scale-up tissue and organ constructs for transplantation.

Science.gov (United States)

Ozbolat, Ibrahim T

2015-07-01

Bioprinting is an emerging field that is having a revolutionary impact on the medical sciences. It offers great precision for the spatial placement of cells, proteins, genes, drugs, and biologically active particles to better guide tissue generation and formation. This emerging biotechnology appears to be promising for advancing tissue engineering toward functional tissue and organ fabrication for transplantation, drug testing, research investigations, and cancer or disease modeling, and has recently attracted growing interest worldwide among researchers and the general public. In this Opinion, I highlight possibilities for the bioprinting scale-up of functional tissue and organ constructs for transplantation and provide the reader with alternative approaches, their limitations, and promising directions for new research prospects. Copyright © 2015 Elsevier Ltd. All rights reserved.

Transcriptomics resources of human tissues and organs

DEFF Research Database (Denmark)

Uhlén, Mathias; Hallström, Björn M.; Lindskog, Cecilia

2016-01-01

a framework for defining the molecular constituents of the human body as well as for generating comprehensive lists of proteins expressed across tissues or in a tissue-restricted manner. Here, we review publicly available human transcriptome resources and discuss body-wide data from independent genome......Quantifying the differential expression of genes in various human organs, tissues, and cell types is vital to understand human physiology and disease. Recently, several large-scale transcriptomics studies have analyzed the expression of protein-coding genes across tissues. These datasets provide...

Neutron organ dose and the influence of adipose tissue

Science.gov (United States)

Simpkins, Robert Wayne

Neutron fluence to dose conversion coefficients have been assessed considering the influences of human adipose tissue. Monte Carlo code MCNP4C was used to simulate broad parallel beam monoenergetic neutrons ranging in energy from thermal to 10 MeV. Simulated Irradiations were conducted for standard irradiation geometries. The targets were on gender specific mathematical anthropomorphic phantoms modified to approximate human adipose tissue distributions. Dosimetric analysis compared adipose tissue influence against reference anthropomorphic phantom characteristics. Adipose Male and Post-Menopausal Female Phantoms were derived introducing interstitial adipose tissue to account for 22 and 27 kg additional body mass, respectively, each demonstrating a Body Mass Index (BMI) of 30. An Adipose Female Phantom was derived introducing specific subcutaneous adipose tissue accounting for 15 kg of additional body mass demonstrating a BMI of 26. Neutron dose was shielded in the superficial tissues; giving rise to secondary photons which dominated the effective dose for Incident energies less than 100 keV. Adipose tissue impact on the effective dose was a 25% reduction at the anterior-posterior incidence ranging to a 10% increase at the lateral incidences. Organ dose impacts were more distinctive; symmetrically situated organs demonstrated a 15% reduction at the anterior-posterior Incidence ranging to a 2% increase at the lateral incidences. Abdominal or asymmetrically situated organs demonstrated a 50% reduction at the anterior-posterior incidence ranging to a 25% increase at the lateral incidences.

Bifidobacterium infantis Potentially Alleviates Shrimp Tropomyosin-Induced Allergy by Tolerogenic Dendritic Cell-Dependent Induction of Regulatory T Cells and Alterations in Gut Microbiota

Directory of Open Access Journals (Sweden)

Linglin Fu

2017-11-01

Full Text Available Shellfish is one of the major allergen sources worldwide, and tropomyosin (Tm is the predominant allergic protein in shellfish. Probiotics has been appreciated for its beneficial effects on the host, including anti-allergic and anti-inflammatory effects, although the underlying mechanisms were not fully understood. In this study, oral administration of probiotic strain Bifidobacterium infantis 14.518 (Binf effectively suppressed Tm-induced allergic response in a mouse model by both preventive and therapeutic strategies. Further results showed that Binf stimulated dendritic cells (DCs maturation and CD103+ tolerogenic DCs accumulation in gut-associated lymphoid tissue, which subsequently induced regulatory T cells differentiation for suppressing Th2-biased response. We also found that Binf regulates the alterations of gut microbiota composition. Specifically, the increase of Dorea and decrease of Ralstonia is highly correlated with Th2/Treg ratio and may contribute to alleviating Tm-induced allergic responses. Our findings provide molecular insight into the application of Binf in alleviating food allergy and even gut immune homeostasis.

Dietary intake and burden of lanthanide in main organs and tissues for Chinese man

International Nuclear Information System (INIS)

Zhu Hongda; Liu Qingfeng; Ouyang Li; Liu Husheng; Wang Naifen; Liu Yaqiong; Zhang Yongbao; Wang Ke; Chen Rusong

2004-01-01

Objective: To determine lanthanide concentrations in dietary foods and main organs or tissues for Chinese adult man and to estimate their daily intakes by ingestion and organ or tissue burdens. Methods: Ten kinds of organ or tissue samples collected in autopsy from 21 supplemental subjects of 4 areas with different dietary types in China who died suddenly, and had been healthy and normal before death. The concentrations of 11 lanthanide in foods and 14 lanthanide in these organ or tissue samples, including those collected from 31 subjects in the past, were analyzed by using ICP-MS or INAA technique as well as necessary QC measures. With uses of the local diet composition and relevant organ or tissue weights for Chinese Reference Man, their daily intakes and organ or tissue burdens were estimated. Results: The concentrations of 14 lanthanide in 12 categories of foods and 10 kinds of organ or tissue samples, their dietary daily intakes and organ or tissue burdens for Chinese adult men were obtained. Conclusion: Besides updating the relevant data of La, Ce and Eu in 5 kinds of organ or tissue and diet, this research obtained data on concentrations of other 11 lanthanide in Chinese foods and 10 kinds of organ or tissue, their daily intakes and burdens for the first time in China. The results provide more systematic bases for developing the parameters of Chinese Reference Man than before. This study provides also comparative data for different kinds of lanthanide, foods, organs or tissues and also the background values of Chinese soil

Tissue engineering and cell-based therapy toward integrated strategy with artificial organs.

Science.gov (United States)

Gojo, Satoshi; Toyoda, Masashi; Umezawa, Akihiro

2011-09-01

Research in order that artificial organs can supplement or completely replace the functions of impaired or damaged tissues and internal organs has been underway for many years. The recent clinical development of implantable left ventricular assist devices has revolutionized the treatment of patients with heart failure. The emerging field of regenerative medicine, which uses human cells and tissues to regenerate internal organs, is now advancing from basic and clinical research to clinical application. In this review, we focus on the novel biomaterials, i.e., fusion protein, and approaches such as three-dimensional and whole-organ tissue engineering. We also compare induced pluripotent stem cells, directly reprogrammed cardiomyocytes, and somatic stem cells for cell source of future cell-based therapy. Integrated strategy of artificial organ and tissue engineering/regenerative medicine should give rise to a new era of medical treatment to organ failure.

The complementarity of the technical tools of tissue engineering and the concepts of artificial organs for the design of functional bioartificial tissues.

Science.gov (United States)

Lenas, Petros; Moreno, Angel; Ikonomou, Laertis; Mayer, Joerg; Honda, Hiroyuki; Novellino, Antonio; Pizarro, Camilo; Nicodemou-Lena, Eleni; Rodergas, Silvia; Pintor, Jesus

2008-09-01

Although tissue engineering uses powerful biological tools, it still has a weak conceptual foundation, which is restricted at the cell level. The design criteria at the cell level are not directly related with the tissue functions, and consequently, such functions cannot be implemented in bioartificial tissues with the currently used methods. On the contrary, the field of artificial organs focuses on the function of the artificial organs that are treated in the design as integral entities, instead of the optimization of the artificial organ components. The field of artificial organs has already developed and tested methodologies that are based on system concepts and mathematical-computational methods that connect the component properties with the desired global organ function. Such methodologies are needed in tissue engineering for the design of bioartificial tissues with tissue functions. Under the framework of biomedical engineering, artificial organs and tissue engineering do not present competitive approaches, but are rather complementary and should therefore design a common future for the benefit of patients.

Space research on organs and tissues

Science.gov (United States)

Tischler, Marc E.; Morey-Holton, Emily

1993-01-01

Studies in space on various physiological systems have and will continue to provide valuable information on how they adapt to reduced gravitational conditions, and how living in a 1 g (gravity) environment has guided their development. Muscle and bone are the most notable tissues that respond to unweighting caused by lack of gravity. The function of specific muscles and bones relates directly to mechanical loading, so that removal of 'normal forces' in space, or in bedridden patients, causes dramatic loss of tissue mass. The cardiovascular system is also markedly affected by reduced gravity. Adaptation includes decreased blood flow to the lower extremities, thus decreasing the heart output requirement. Return to 1 g is associated with a period of reconditioning due to the deconditioning that occurs in space. Changes in the cardiovascular system are also related to responses of the kidney and certain endocrine (hormone-producing) organs. Changes in respiratory function may also occur, suggesting an effect on the lungs, though this adaptation is poorly understood. The neurovestibular system, including the brain and organs of the inner ear, must adapt to the disorientation caused by lack of gravity. Preliminary findings have been reported for liver. Additionally, endocrine organs responsible for release of hormones such as insulin, growth hormone, glucocorticoids, and thyroid hormone may respond to spaceflight.

3D bioprinting of tissues and organs.

Science.gov (United States)

Murphy, Sean V; Atala, Anthony

2014-08-01

Additive manufacturing, otherwise known as three-dimensional (3D) printing, is driving major innovations in many areas, such as engineering, manufacturing, art, education and medicine. Recent advances have enabled 3D printing of biocompatible materials, cells and supporting components into complex 3D functional living tissues. 3D bioprinting is being applied to regenerative medicine to address the need for tissues and organs suitable for transplantation. Compared with non-biological printing, 3D bioprinting involves additional complexities, such as the choice of materials, cell types, growth and differentiation factors, and technical challenges related to the sensitivities of living cells and the construction of tissues. Addressing these complexities requires the integration of technologies from the fields of engineering, biomaterials science, cell biology, physics and medicine. 3D bioprinting has already been used for the generation and transplantation of several tissues, including multilayered skin, bone, vascular grafts, tracheal splints, heart tissue and cartilaginous structures. Other applications include developing high-throughput 3D-bioprinted tissue models for research, drug discovery and toxicology.

[Attitude towards organ and tissue donation in Europe : Prerequisite for osteochondral allograft treatment].

Science.gov (United States)

Schmidt, S; Schulte, A; Schwarz, S; Hofmann, N; Tietz, S; Boergel, M; Sixt, S U

2017-11-01

The biggest obstacle to overcome for routine treatment of various pathologies with fresh osteochondral allograft is the availability of tissue for transplantation. Large fresh osteochondral allografts are usually harvested from organ donors, but in contrast to organs, tissues can be procured after cardiac arrest. Medical staff as well the general public are much less aware of the possibilities and requirements of tissue donation compared to organ donation. This review aims to highlight the current situation of organ and tissue donation in Europe and to raise this much needed awareness. For this research, PubMed database was scanned using the terms "tissue/organ donation", "bone donation/transplantation", "cartilage transplantation/allografts" and "osteochrondral allografts". Relatives of potential donors are often not approached because physicians and nurses do not feel sufficiently prepared for this task and, thus, are reluctant to address this topic. Different options could alleviate the pressure medical staff is feeling. Furthermore, there are different factors influencing consent that can be addressed to increase donation rates. Currently, a lot of potential concerning musculoskeletal tissue grafts remains unused. Most importantly, families should be encouraged to speak about their potenzial will to donate and educational programs should be established to increase trust in organ and tissue donation and the allocation system and to increase knowledge about the importance of transplantation medicine. But joined efforts of different parts of the medical systems and different organizations involved in tissue transplantation should improve the situation for patients waiting for much needed transplants.

An analysis of knowledge and attitudes of hospice staff towards organ and tissue donation.

Science.gov (United States)

Wale, J; Arthur, A; Faull, C

2014-03-01

Only a minority of hospice patients eligible to donate tissue and organs choose to do so. Hospice care staff play a key role in discussions about donation, but their willingness to engage in these discussions and their understanding of issues around tissue and organ donation is poorly understood. To (i) identify factors associated with the wish of hospice doctors, nurses and healthcare assistants to donate their own organs after death; (ii) survey the experience of discussing the subject with patients; (iii) determine staff members' knowledge of organ and tissue donation and (iv) identify factors associated with knowledge of organ and tissue donation. Cross-sectional questionnaire survey of hospice care staff. 76 of the 94 care staff of one large UK hospice completed and returned the questionnaire. Staff wishing to donate their organs after death (43/76 56.6%) were more likely to be doctors or nurses than healthcare assistants (p=0.011) and more likely to have discussed organ or tissue donation with their family (pdonation with patients had more years' experience (p=0.045) and had similarly discussed donation with their own family (p=0.039). Those with greater knowledge were more likely to have discussed organ or tissue donation with a patient (p=0.042). A reluctance to instigate discussions about organ and tissue donation may prevent palliative patients and their families being allowed the opportunity to donate. Suboptimal knowledge among hospice staff suggests the need for greater liaison between hospice staff, and the organ and tissue donation teams.

Chapter 8. Ionisation radiation and human organism. Radioactivity of human tissues

International Nuclear Information System (INIS)

Toelgyessy, J.; Harangozo, M.

2000-01-01

This is a chapter of textbook of radioecology for university students. In this chapter authors deal with ionisation radiation and human organism as well as with radioactivity of human tissues. Chapter consists of next parts: (1) Radiation stress of human organism; (2) Radioactivity of human tissues and the factors influencing radioactive contamination; (3) Possibilities of decreasing of radiation stress

[Ornithine decarboxylase in mammalian organs and tissues at hibernation and artificial hypobiosis].

Science.gov (United States)

Logvinovich, O S; Aksenova, G E

2013-01-01

Ornithine decarboxylase (ODC, EC 4.1.1.17.) is a short-lived and dynamically regulated enzyme of polyamines biosynthesis. Regulation of functional, metabolic and proliferative state of organs and tissues involves the modifications of the ODC enzymatic activity. The organ-specific changes in ODC activity were revealed in organs and tissues (liver, spleen, bone marrow, kidney, and intestinal mucosa) of hibernating mammals - squirrels Spermophilus undulates - during the hibernating season. At that, a positive correlation was detected between the decline and recovery of the specialized functions of organs and tissues and the respective modifications of ODC activity during hibernation bouts. Investigation of changes in ODC activity in organs and tissues of non-hibernating mammals under artificial hypobiosis showed that in Wistar rats immediately after exposure to hypothermia-hypoxia-hypercapnia (hypobiosis) the level of ODC activity was low in thymus, spleen, small intestine mucosa, neocortex, and liver. The most marked reduction in enzyme activity was observed in actively proliferating tissues: thymus, spleen, small intestine mucosa. In bone marrow of squirrels, while in a state of torpor, as well as in thymus of rats after exposure to hypothermia-hypoxia-hypercapnia, changes in the ODC activity correlated with changes in the rate of cell proliferation (by the criterion of cells distribution over cell cycle). The results obtained, along with the critical analysis of published data, indicate that the ODC enzyme is involved in biochemical adaptation of mammals to natural and artificial hypobiosis. A decline in the ODC enzymatic activity indicates a decline in proliferative, functional, and metabolic activity of organs and tissues of mammals (bone marrow, mucosa of small intestine, thymus, spleen, neocortex, liver, kidneys) when entering the state of hypobiosis.

Role of nanotopography in the development of tissue engineered 3D organs and tissues using mesenchymal stem cells.

Science.gov (United States)

Salmasi, Shima; Kalaskar, Deepak M; Yoon, Wai-Weng; Blunn, Gordon W; Seifalian, Alexander M

2015-03-26

Recent regenerative medicine and tissue engineering strategies (using cells, scaffolds, medical devices and gene therapy) have led to fascinating progress of translation of basic research towards clinical applications. In the past decade, great deal of research has focused on developing various three dimensional (3D) organs, such as bone, skin, liver, kidney and ear, using such strategies in order to replace or regenerate damaged organs for the purpose of maintaining or restoring organs' functions that may have been lost due to aging, accident or disease. The surface properties of a material or a device are key aspects in determining the success of the implant in biomedicine, as the majority of biological reactions in human body occur on surfaces or interfaces. Furthermore, it has been established in the literature that cell adhesion and proliferation are, to a great extent, influenced by the micro- and nano-surface characteristics of biomaterials and devices. In addition, it has been shown that the functions of stem cells, mesenchymal stem cells in particular, could be regulated through physical interaction with specific nanotopographical cues. Therefore, guided stem cell proliferation, differentiation and function are of great importance in the regeneration of 3D tissues and organs using tissue engineering strategies. This review will provide an update on the impact of nanotopography on mesenchymal stem cells for the purpose of developing laboratory-based 3D organs and tissues, as well as the most recent research and case studies on this topic.

Sociocultural perspective on organ and tissue donation among reservation-dwelling American Indian adults.

Science.gov (United States)

Fahrenwald, Nancy L; Stabnow, Wendy

2005-11-01

To discover the sociocultural patterns that influence decisions about organ and tissue donation among American Indian (AI) adults. This qualitative ethnographic study used a social-ecological framework. A snowball sampling technique was used to recruit 21 Oglala Lakota Sioux participants (age >or= 19 years) living on the Pine Ridge Indian Reservation in South Dakota, USA. Face-to-face interviews were conducted using open-ended questions derived from the social-ecological perspective of Stokols (1992). Interviews were audiotaped and transcribed. Data were categorized into construct codes to identify concepts and to discover emerging themes. Personal and environmental themes regarding organ and tissue donation emerged. There were two personal themes: uncertain knowledge and the diabetes crisis. Participants knew very little about organ and tissue donation but there was a basic understanding of donor/recipient compatibility. The prevalence of diabetes in the community is contributing to a dire need for kidney donors. The diabetes crisis was acknowledged by every participant. There were three environmental themes: cultural transitions, healthcare system competence and outreach efforts. Traditional cultural beliefs such as entering the spirit world with an intact body were acknowledged. However, conversations reflected re-examination of traditional beliefs because of the need for kidney donors. The healthcare environmental context of organ and tissue donation emerged as a theme. Participants were not confident that the local health system was prepared to either address traditional beliefs about organ and tissue donation or implement a donation protocol. The final theme was the environmental context of outreach efforts. Participants desired relevant outreach targeted to the community and disseminated through local communication networks including the family, the media and tribal leaders. Sociocultural factors relevant to the personal and environmental context of the

A strategy for tissue self-organization that is robust to cellular heterogeneity and plasticity.

Science.gov (United States)

Cerchiari, Alec E; Garbe, James C; Jee, Noel Y; Todhunter, Michael E; Broaders, Kyle E; Peehl, Donna M; Desai, Tejal A; LaBarge, Mark A; Thomson, Matthew; Gartner, Zev J

2015-02-17

Developing tissues contain motile populations of cells that can self-organize into spatially ordered tissues based on differences in their interfacial surface energies. However, it is unclear how self-organization by this mechanism remains robust when interfacial energies become heterogeneous in either time or space. The ducts and acini of the human mammary gland are prototypical heterogeneous and dynamic tissues comprising two concentrically arranged cell types. To investigate the consequences of cellular heterogeneity and plasticity on cell positioning in the mammary gland, we reconstituted its self-organization from aggregates of primary cells in vitro. We find that self-organization is dominated by the interfacial energy of the tissue-ECM boundary, rather than by differential homo- and heterotypic energies of cell-cell interaction. Surprisingly, interactions with the tissue-ECM boundary are binary, in that only one cell type interacts appreciably with the boundary. Using mathematical modeling and cell-type-specific knockdown of key regulators of cell-cell cohesion, we show that this strategy of self-organization is robust to severe perturbations affecting cell-cell contact formation. We also find that this mechanism of self-organization is conserved in the human prostate. Therefore, a binary interfacial interaction with the tissue boundary provides a flexible and generalizable strategy for forming and maintaining the structure of two-component tissues that exhibit abundant heterogeneity and plasticity. Our model also predicts that mutations affecting binary cell-ECM interactions are catastrophic and could contribute to loss of tissue architecture in diseases such as breast cancer.

Leiomyosarcoma: A rare soft tissue cancer arising from multiple organs

Directory of Open Access Journals (Sweden)

Zorawar Singh

2018-03-01

Full Text Available Leiomyosarcoma (LMS, a smooth muscle connective tissue tumor, is a rare form of cancer which accounts for 5–10% of soft tissue sarcomas. This type of cancer is highly unpredictable. LMS is a resistant type of cancer and can remain in the dormant state for long time. It can recur in the later stages of life. LMS has been reported in different animals including humans. A wide literature search was done. The PubMed database was used to search for journal articles on the occurrence of LMS in different organs from 1950 to 2016. LMS has been reported to be associated with different organs, including esophagus, stomach, intestine, anus and uterus. In this article, an attempt has been made to review the studies based on occurrence of LMS with respect to the organs affected and frequency of publications. Finding the organ-associated occurrence of LMS may be useful in assessing the overall risk and formulating future cancer preventive strategies.

Geometry-driven cell organization determines tissue growths in scaffold pores: consequences for fibronectin organization.

Directory of Open Access Journals (Sweden)

Pascal Joly

Full Text Available To heal tissue defects, cells have to bridge gaps and generate new extracellular matrix (ECM. Macroporous scaffolds are frequently used to support the process of defect filling and thus foster tissue regeneration. Such biomaterials contain micro-voids (pores that the cells fill with their own ECM over time. There is only limited knowledge on how pore geometry influences cell organization and matrix production, even though it is highly relevant for scaffold design. This study hypothesized that 1 a simple geometric description predicts cellular organization during pore filling at the cell level and that 2 pore closure results in a reorganization of ECM. Scaffolds with a broad distribution of pore sizes (macroporous starPEG-heparin cryogel were used as a model system and seeded with primary fibroblasts. The strategies of cells to fill pores could be explained by a simple geometrical model considering cells as tensioned chords. The model matched qualitatively as well as quantitatively by means of cell number vs. open cross-sectional area for all pore sizes. The correlation between ECM location and cell position was higher when the pores were not filled with tissue (Pearson's coefficient ρ = 0.45±0.01 and reduced once the pores were closed (ρ = 0.26±0.04 indicating a reorganization of the cell/ECM network. Scaffold pore size directed the time required for pore closure and furthermore impacted the organization of the fibronectin matrix. Understanding how cells fill micro-voids will help to design biomaterial scaffolds that support the endogenous healing process and thus allow a fast filling of tissue defects.

Autoimmunity to Tropomyosin-Specific Peptides Induced by Mycobacterium leprae in Leprosy Patients: Identification of Mimicking Proteins.

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Singh, Itu; Yadav, Asha Ram; Mohanty, Keshar Kunja; Katoch, Kiran; Sharma, Prashant; Pathak, Vinay Kumar; Bisht, Deepa; Gupta, Umesh D; Sengupta, Utpal

2018-01-01

It has been shown earlier that there is a rise in the levels of autoantibodies and T cell response to cytoskeletal proteins in leprosy. Our group recently demonstrated a rise in both T and B cell responses to keratin and myelin basic protein in all types of leprosy patients and their associations in type 1 reaction (T1R) group of leprosy. In this study, we investigated the association of levels of autoantibodies and lymphoproliferation against myosin in leprosy patients across the spectrum and tried to find out the mimicking proteins or epitopes between host protein and protein/s of Mycobacterium leprae . One hundred and sixty-nine leprosy patients and 55 healthy controls (HC) were enrolled in the present study. Levels of anti-myosin antibodies and T-cell responses against myosin were measured by ELISA and lymphoproliferation assay, respectively. Using 2-D gel electrophoresis, western blot and MALDI-TOF/TOF antibody-reactive spots were identified. Three-dimensional structure of mimicking proteins was modeled by online server. B cell epitopes of the proteins were predicted by BCPREDS server 1.0 followed by identification of mimicking epitopes. Mice of inbred BALB/c strain were hyperimmunized with M. leprae soluble antigen (MLSA) and splenocytes and lymph node cells of these animals were adoptively transferred to naïve mice. Highest level of anti-myosin antibodies was noted in sera of T1R leprosy patients. We observed significantly higher levels of lymphoproliferative response ( p  leprae . We found four mimicking epitopes between these sequences. These data suggest that these mimicking proteins tropomyosin and ATP-dependent Clp protease ATP-binding subunit of M. leprae or more precisely mimicking epitopes (four B cell epitopes) might be responsible for extensive tissue damage during type1 reaction in leprosy.

Cell type-specific characterization of nuclear DNA contents within complex tissues and organs

Directory of Open Access Journals (Sweden)

Lambert Georgina M

2005-10-01

Full Text Available Abstract Background Eukaryotic organisms are defined by the presence of a nucleus, which encloses the chromosomal DNA, and is characterized by its DNA content (C-value. Complex eukaryotic organisms contain organs and tissues that comprise interspersions of different cell types, within which polysomaty, endoreduplication, and cell cycle arrest is frequently observed. Little is known about the distribution of C-values across different cell types within these organs and tissues. Results We have developed, and describe here, a method to precisely define the C-value status within any specific cell type within complex organs and tissues of plants. We illustrate the application of this method to Arabidopsis thaliana, specifically focusing on the different cell types found within the root. Conclusion The method accurately and conveniently charts C-value within specific cell types, and provides novel insight into developmental processes. The method is, in principle, applicable to any transformable organism, including mammals, within which cell type specificity of regulation of endoreduplication, of polysomaty, and of cell cycle arrest is suspected.

Experience of nurses in the process of donation of organs and tissues for transplant.

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de Moraes, Edvaldo Leal; dos Santos, Marcelo José; Merighi, Miriam Aparecida Barbosa; Massarollo, Maria Cristina Komatsu Braga

2014-01-01

to investigate the meaning of the action of nurses in the donation process to maintain the viability of organs and tissues for transplantation. this qualitative study with a social phenomenological approach was conducted through individual interviews with ten nurses of three Organ and Tissue Procurement Services of the city of São Paulo. the experience of the nurses in the donation process was represented by the categories: obstacles experienced in the donation process, and interventions performed. The meaning of the action to maintain the viability of organs and tissues for transplantation was described by the categories: to change paradigms, to humanize the donation process, to expand the donation, and to save lives. knowledge of the experience of the nurses in this process is important for healthcare professionals who work in different realities, indicating strategies to optimize the procurement of organs and tissues for transplantation.

4D printing of polymeric materials for tissue and organ regeneration.

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Miao, Shida; Castro, Nathan; Nowicki, Margaret; Xia, Lang; Cui, Haitao; Zhou, Xuan; Zhu, Wei; Lee, Se-Jun; Sarkar, Kausik; Vozzi, Giovanni; Tabata, Yasuhiko; Fisher, John; Zhang, Lijie Grace

2017-12-01

Four dimensional (4D) printing is an emerging technology with great capacity for fabricating complex, stimuli-responsive 3D structures, providing great potential for tissue and organ engineering applications. Although the 4D concept was first highlighted in 2013, extensive research has rapidly developed, along with more-in-depth understanding and assertions regarding the definition of 4D. In this review, we begin by establishing the criteria of 4D printing, followed by an extensive summary of state-of-the-art technological advances in the field. Both transformation-preprogrammed 4D printing and 4D printing of shape memory polymers are intensively surveyed. Afterwards we will explore and discuss the applications of 4D printing in tissue and organ regeneration, such as developing synthetic tissues and implantable scaffolds, as well as future perspectives and conclusions.

Tissue organization by cadherin adhesion molecules: dynamic molecular and cellular mechanisms of morphogenetic regulation

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Niessen, Carien M.; Leckband, Deborah; Yap, Alpha S.

2013-01-01

This review addresses the cellular and molecular mechanisms of cadherin-based tissue morphogenesis. Tissue physiology is profoundly influenced by the distinctive organizations of cells in organs and tissues. In metazoa, adhesion receptors of the classical cadherin family play important roles in establishing and maintaining such tissue organization. Indeed, it is apparent that cadherins participate in a range of morphogenetic events that range from support of tissue integrity to dynamic cellular rearrangements. A comprehensive understanding of cadherin-based morphogenesis must then define the molecular and cellular mechanisms that support these distinct cadherin biologies. Here we focus on four key mechanistic elements: the molecular basis for adhesion through cadherin ectodomains; the regulation of cadherin expression at the cell surface; cooperation between cadherins and the actin cytoskeleton; and regulation by cell signaling. We discuss current progress and outline issues for further research in these fields. PMID:21527735

Sensing of EGTA Mediated Barrier Tissue Disruption with an Organic Transistor

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Scherrine Tria

2013-01-01

Full Text Available Barrier tissue protects the body against external factors by restricting the passage of molecules. The gastrointestinal epithelium is an example of barrier tissue with the primary purpose of allowing the passage of ions and nutrients, while restricting the passage of pathogens and toxins. It is well known that the loss of barrier function can be instigated by a decrease in extracellular calcium levels, leading to changes in protein conformation and an increase in paracellular transport. In this study, ethylene glycol-bis(beta-aminoethyl ether-N,N,N',N'-tetra acetic acid (EGTA, a calcium chelator, was used to disrupt the gastrointestinal epithelial barrier. The effect of EGTA on barrier tissue was monitored by a novel label-free method based on an organic electrochemical transistor (OECT integrated with living cells and validated against conventional methods for measuring barrier tissue integrity. We demonstrate that the OECT can detect breaches in barrier tissue upon exposure to EGTA with the same sensitivity as existing methods but with increased temporal resolution. Due to the potential of low cost processing techniques and the flexibility in design associated with organic electronics, the OECT has great potential for high-throughput, disposable sensing and diagnostics.

The Maillard Reaction Reduced the Sensitization of Tropomyosin and Arginine Kinase from Scylla paramamosain, Simultaneously.

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Han, Xin-Yu; Yang, Huang; Rao, Shi-Tao; Liu, Guang-Yu; Hu, Meng-Jun; Zeng, Bin-Chang; Cao, Min-Jie; Liu, Guang-Ming

2018-03-21

The Maillard reaction was established to reduce the sensitization of tropomyosin (TM) and arginine kinase (AK) from Scylla paramamosain, and the mechanism of the attenuated sensitization was investigated. In the present study, the Maillard reaction conditions were optimized for heating at 100 °C for 60 min (pH 8.5) with arabinose. A low level of allergenicity in mice was shown by the levels of allergen-specific antibodies, and more Th1 and less Th2 cells cytokines produced and associated transcription factors with the Maillard reacted allergen (mAllergen). The tolerance potency in mice was demonstrated by the increased ratio of Th1/Th2 cytokines. Moreover, mass spectrometry analysis showed that some key amino acids of IgE-binding epitopes (K 112 , R 125 , R 133 of TM; K 33 , K 118 , R 202 of AK) were modified by the Maillard reaction. The Maillard reaction with arabinose reduced the sensitization of TM and AK, which may be due to the masked epitopes.

Tissue engineering as a potential alternative or adjunct to surgical reconstruction in treating pelvic organ prolapse

DEFF Research Database (Denmark)

Boennelycke, M; Gräs, Søren; Lose, G

2013-01-01

Cell-based tissue engineering strategies could potentially provide attractive alternatives to surgical reconstruction of native tissue or the use of surgical implants in treating pelvic organ prolapse (POP).......Cell-based tissue engineering strategies could potentially provide attractive alternatives to surgical reconstruction of native tissue or the use of surgical implants in treating pelvic organ prolapse (POP)....

Experience of nurses in the process of donation of organs and tissues for transplant

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Edvaldo Leal de Moraes

2014-04-01

Full Text Available OBJECTIVE: to investigate the meaning of the action of nurses in the donation process to maintain the viability of organs and tissues for transplantation.METHOD: this qualitative study with a social phenomenological approach was conducted through individual interviews with ten nurses of three Organ and Tissue Procurement Services of the city of São Paulo.RESULTS: the experience of the nurses in the donation process was represented by the categories: obstacles experienced in the donation process, and interventions performed. The meaning of the action to maintain the viability of organs and tissues for transplantation was described by the categories: to change paradigms, to humanize the donation process, to expand the donation, and to save lives.FINAL CONSIDERATIONS: knowledge of the experience of the nurses in this process is important for healthcare professionals who work in different realities, indicating strategies to optimize the procurement of organs and tissues for transplantation.

Regeneration of Tissues and Organs Using Autologous Cells

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Anthony Atala, M D

2012-10-11

The proposed work aims to address three major challenges to the field of regenerative medicine: 1) the growth and expansion of regenerative cells outside the body in controlled in vitro environments, 2) supportive vascular supply for large tissue engineered constructs, and 3) interactive biomaterials that can orchestrate tissue development in vivo. Toward this goal, we have engaged a team of scientists with expertise in cell and molecular biology, physiology, biomaterials, controlled release, nanomaterials, tissue engineering, bioengineering, and clinical medicine to address all three challenges. This combination of resources, combined with the vast infrastructure of the WFIRM, have brought to bear on projects to discover and test new sources of autologous cells that can be used therapeutically, novel methods to improve vascular support for engineered tissues in vivo, and to develop intelligent biomaterials and bioreactor systems that interact favorably with stem and progenitor cells to drive tissue maturation. The Institute's ongoing programs are aimed at developing regenerative medicine technologies that employ a patient's own cells to help restore or replace tissue and organ function. This DOE program has provided a means to solve some of the vexing problems that are germane to many tissue engineering applications, regardless of tissue type or target disease. By providing new methods that are the underpinning of tissue engineering, this program facilitated advances that can be applied to conditions including heart disease, diabetes, renal failure, nerve damage, vascular disease, and cancer, to name a few. These types of conditions affect millions of Americans at a cost of more than $400 billion annually. Regenerative medicine holds the promise of harnessing the body's own power to heal itself. By addressing the fundamental challenges of this field in a comprehensive and focused fashion, this DOE program has opened new opportunities to treat

The Occurrence of Sequences Identical with Epitopes from the Allergen Pen a 1.0102 Among Food and Non-Food Proteins

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Minkiewicz Piotr

2015-03-01

Full Text Available The presence of common epitopes among tropomyosins of invertebrates, including arthropods, e.g. edible ones, may help to explain the molecular basis of cross-reactivity between allergens. The work presented is the first survey concerning global distribution of epitopes from Pen a 1.0102 in universal proteome. In the group of known tropomyosin epitopes, the fragment with the sequence ESKIVELEEEL was found in the sequence of channel catfish (Ictalurus punctatus tropomyosin. To date, this is the first result suggesting the presence of a complete sequential epitope interacting with gE in vertebrate tropomyosin. Another fragment with the sequence VAALNRRIQL, a major part of the epitope, was found in 11 fish, 8 amphibians, 3 birds, 19 mammalians and 4 human tropomyosin sequences. Identical epitopes are common in sequences of invertebrate tropomyosins, including food and non-food allergens annotated in the Allergome database. The rare pentapeptide with the DEERM sequence occurs in proteins not sharing homology with tropomyosins. Pathogenic microorganisms are the most abundant category of organisms synthesizing such proteins.

The promise of organ and tissue preservation to transform medicine.

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Giwa, Sebastian; Lewis, Jedediah K; Alvarez, Luis; Langer, Robert; Roth, Alvin E; Church, George M; Markmann, James F; Sachs, David H; Chandraker, Anil; Wertheim, Jason A; Rothblatt, Martine; Boyden, Edward S; Eidbo, Elling; Lee, W P Andrew; Pomahac, Bohdan; Brandacher, Gerald; Weinstock, David M; Elliott, Gloria; Nelson, David; Acker, Jason P; Uygun, Korkut; Schmalz, Boris; Weegman, Brad P; Tocchio, Alessandro; Fahy, Greg M; Storey, Kenneth B; Rubinsky, Boris; Bischof, John; Elliott, Janet A W; Woodruff, Teresa K; Morris, G John; Demirci, Utkan; Brockbank, Kelvin G M; Woods, Erik J; Ben, Robert N; Baust, John G; Gao, Dayong; Fuller, Barry; Rabin, Yoed; Kravitz, David C; Taylor, Michael J; Toner, Mehmet

2017-06-07

The ability to replace organs and tissues on demand could save or improve millions of lives each year globally and create public health benefits on par with curing cancer. Unmet needs for organ and tissue preservation place enormous logistical limitations on transplantation, regenerative medicine, drug discovery, and a variety of rapidly advancing areas spanning biomedicine. A growing coalition of researchers, clinicians, advocacy organizations, academic institutions, and other stakeholders has assembled to address the unmet need for preservation advances, outlining remaining challenges and identifying areas of underinvestment and untapped opportunities. Meanwhile, recent discoveries provide proofs of principle for breakthroughs in a family of research areas surrounding biopreservation. These developments indicate that a new paradigm, integrating multiple existing preservation approaches and new technologies that have flourished in the past 10 years, could transform preservation research. Capitalizing on these opportunities will require engagement across many research areas and stakeholder groups. A coordinated effort is needed to expedite preservation advances that can transform several areas of medicine and medical science.

Role of tropomyosin as a cross-reacting allergen in sensitization to cockroach in patients from Martinique (French Caribbean island) with a respiratory allergy to mite and a food allergy to crab and shrimp

NARCIS (Netherlands)

Purohit, A.; Shao, J.; Degreef, J. M.; van Leeuwen, A.; van Ree, R.; Pauli, G.; de Blay, F.

2007-01-01

BACKGROUND: Tropomyosin has been described as cross-reacting allergen between mite, cockroach and shrimp. METHODS: In 13 patients with asthma and/or rhinitis sensitized to mite and/or German cockroach and presenting urticaria, oral allergy syndrome or angio-edema upon eating shrimp and/or crab, we

Family perspectives on organ and tissue donation for transplantation: a principlist analysis.

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Dos Santos, Marcelo José; Feito, Lydia

2017-01-01

The family interview context is permeated by numerous ethical issues which may generate conflicts and impact on organ donation process. This study aims to analyze the family interview process with a focus on principlist bioethics. This exploratory, descriptive study uses a qualitative approach. The speeches were collected using the following prompt: "Talk about the family interview for the donation of organs and tissues for transplantation, from the preparation for the interview to the decision of the family to donate or not." For the treatment of qualitative data, we chose the method of content analysis and categorical thematic analysis. The study involved 18 nurses who worked in three municipal organ procurement organizations in São Paulo, Brazil, and who conducted family interviews for organ donation. Ethical considerations: The data were collected after approval of the study by the Research Ethics Committee of the School of Nursing of the University of São Paulo. The results were classified into four categories and three subcategories. The categories are the principles adopted by principlist bioethics. The principles of autonomy, beneficence, non-maleficence, and justice permeate the family interview and reveal their importance in the organs and tissues donation process for transplantation. The analysis of family interviews for the donation of organs and tissues for transplantation with a focus on principlist bioethics indicates that the process involves many ethical considerations. The elucidation of these aspects contributes to the discussion, training, and improvement of professionals, whether nurses or not, who work in organ procurement organizations and can improve the curriculum of existing training programs for transplant coordinators who pursue ethics in donation and transplantation as their foundation.

A histological atlas of the tissues and organs of neotenic and metamorphosed axolotl.

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Demircan, Turan; İlhan, Ayşe Elif; Aytürk, Nilüfer; Yıldırım, Berna; Öztürk, Gürkan; Keskin, İlknur

2016-09-01

Axolotl (Ambystoma Mexicanum) has been emerging as a promising model in stem cell and regeneration researches due to its exceptional regenerative capacity. Although it represents lifelong lasting neoteny, induction to metamorphosis with thyroid hormones (THs) treatment advances the utilization of Axolotl in various studies. It has been reported that amphibians undergo anatomical and histological remodeling during metamorphosis and this transformation is crucial for adaptation to terrestrial conditions. However, there is no comprehensive histological investigation regarding the morphological alterations of Axolotl organs and tissues throughout the metamorphosis. Here, we reveal the histological differences or resemblances between the neotenic and metamorphic axolotl tissues. In order to examine structural features and cellular organization of Axolotl organs, we performed Hematoxylin & Eosin, Luxol-Fast blue, Masson's trichrome, Alcian blue, Orcein and Weigart's staining. Stained samples from brain, gallbladder, heart, intestine, liver, lung, muscle, skin, spleen, stomach, tail, tongue and vessel were analyzed under the light microscope. Our findings contribute to the validation of the link between newly acquired functions and structural changes of tissues and organs as observed in tail, skin, gallbladder and spleen. We believe that this descriptive work provides new insights for a better histological understanding of both neotenic and metamorphic Axolotl tissues. Copyright © 2016 Elsevier GmbH. All rights reserved.

The promise of organ and tissue preservation to transform medicine

Science.gov (United States)

Giwa, Sebastian; Lewis, Jedediah K; Alvarez, Luis; Langer, Robert; Roth, Alvin E; Church, George M; Markmann, James F; Sachs, David H; Chandraker, Anil; Wertheim, Jason A; Rothblatt, Martine; Boyden, Edward S; Eidbo, Elling; Lee, W P Andrew; Pomahac, Bohdan; Brandacher, Gerald; Weinstock, David M; Elliott, Gloria; Nelson, David; Acker, Jason P; Uygun, Korkut; Schmalz, Boris; Weegman, Brad P; Tocchio, Alessandro; Fahy, Greg M; Storey, Kenneth B; Rubinsky, Boris; Bischof, John; Elliott, Janet A W; Woodruff, Teresa K; Morris, G John; Demirci, Utkan; Brockbank, Kelvin G M; Woods, Erik J; Ben, Robert N; Baust, John G; Gao, Dayong; Fuller, Barry; Rabin, Yoed; Kravitz, David C; Taylor, Michael J; Toner, Mehmet

2017-01-01

The ability to replace organs and tissues on demand could save or improve millions of lives each year globally and create public health benefits on par with curing cancer. Unmet needs for organ and tissue preservation place enormous logistical limitations on transplantation, regenerative medicine, drug discovery, and a variety of rapidly advancing areas spanning biomedicine. A growing coalition of researchers, clinicians, advocacy organizations, academic institutions, and other stakeholders has assembled to address the unmet need for preservation advances, outlining remaining challenges and identifying areas of underinvestment and untapped opportunities. Meanwhile, recent discoveries provide proofs of principle for breakthroughs in a family of research areas surrounding biopreservation. These developments indicate that a new paradigm, integrating multiple existing preservation approaches and new technologies that have flourished in the past 10 years, could transform preservation research. Capitalizing on these opportunities will require engagement across many research areas and stakeholder groups. A coordinated effort is needed to expedite preservation advances that can transform several areas of medicine and medical science. PMID:28591112

Strain-induced collagen organization at the micro-level in fibrin-based engineered tissue constructs

NARCIS (Netherlands)

Jonge, de N.; Kanters, F.M.W.; Baaijens, F.P.T.; Bouten, C.V.C.

2013-01-01

Full understanding of strain-induced collagen organization in complex tissue geometries to create tissues with predefined collagen architecture has not been achieved. This is mainly due to our limited knowledge of collagen remodeling in developing tissues. Here we investigate strain-induced collagen

Energy absorption buildup factors of human organs and tissues at energies and penetration depths relevant for radiotherapy and diagnostics

DEFF Research Database (Denmark)

Manohara, S. R.; Hanagodimath, S. M.; Gerward, Leif

2011-01-01

Energy absorption geometric progression (GP) fitting parameters and the corresponding buildup factors have been computed for human organs and tissues, such as adipose tissue, blood (whole), cortical bone, brain (grey/white matter), breast tissue, eye lens, lung tissue, skeletal muscle, ovary......, testis, soft tissue, and soft tissue (4-component), for the photon energy range 0.015-15 MeV and for penetration depths up to 40 mfp (mean free path). The chemical composition of human organs and tissues is seen to influence the energy absorption buildup factors. It is also found that the buildup factor...... of human organs and tissues changes significantly with the change of incident photon energy and effective atomic number, Zeff. These changes are due to the dominance of different photon interaction processes in different energy regions and different chemical compositions of human organs and tissues...

Genetic control of organ shape and tissue polarity.

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Amelia A Green

2010-11-01

Full Text Available The mechanisms by which genes control organ shape are poorly understood. In principle, genes may control shape by modifying local rates and/or orientations of deformation. Distinguishing between these possibilities has been difficult because of interactions between patterns, orientations, and mechanical constraints during growth. Here we show how a combination of growth analysis, molecular genetics, and modelling can be used to dissect the factors contributing to shape. Using the Snapdragon (Antirrhinum flower as an example, we show how shape development reflects local rates and orientations of tissue growth that vary spatially and temporally to form a dynamic growth field. This growth field is under the control of several dorsoventral genes that influence flower shape. The action of these genes can be modelled by assuming they modulate specified growth rates parallel or perpendicular to local orientations, established by a few key organisers of tissue polarity. Models in which dorsoventral genes only influence specified growth rates do not fully account for the observed growth fields and shapes. However, the data can be readily explained by a model in which dorsoventral genes also modify organisers of tissue polarity. In particular, genetic control of tissue polarity organisers at ventral petal junctions and distal boundaries allows both the shape and growth field of the flower to be accounted for in wild type and mutants. The results suggest that genetic control of tissue polarity organisers has played a key role in the development and evolution of shape.

Comprehensive analysis of tropomyosin isoforms in skeletal muscles by top-down proteomics.

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Jin, Yutong; Peng, Ying; Lin, Ziqing; Chen, Yi-Chen; Wei, Liming; Hacker, Timothy A; Larsson, Lars; Ge, Ying

2016-04-01

Mammalian skeletal muscles are heterogeneous in nature and are capable of performing various functions. Tropomyosin (Tpm) is a major component of the thin filament in skeletal muscles and plays an important role in controlling muscle contraction and relaxation. Tpm is known to consist of multiple isoforms resulting from different encoding genes and alternative splicing, along with post-translational modifications. However, a systematic characterization of Tpm isoforms in skeletal muscles is still lacking. Therefore, we employed top-down mass spectrometry (MS) to identify and characterize Tpm isoforms present in different skeletal muscles from multiple species, including swine, rat, and human. Our study revealed that Tpm1.1 and Tpm2.2 are the two major Tpm isoforms in swine and rat skeletal muscles, whereas Tpm1.1, Tpm2.2, and Tpm3.12 are present in human skeletal muscles. Tandem MS was utilized to identify the sequences of the major Tpm isoforms. Furthermore, quantitative analysis revealed muscle-type specific differences in the abundance of un-modified and modified Tpm isoforms in rat and human skeletal muscles. This study represents the first systematic investigation of Tpm isoforms in skeletal muscles, which not only demonstrates the capabilities of top-down MS for the comprehensive characterization of skeletal myofilament proteins but also provides the basis for further studies on these Tpm isoforms in muscle-related diseases.

Leading Efforts to Increase Organ Donation Through Professionalization of Organ Procurement Organizations and Establishment of Organ and Tissue Donor Registries.

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Vertanous, T; Czer, L S C; de Robertis, M; Kiankhooy, A; Kobashigawa, J; Esmailian, F; Trento, A

2016-01-01

The influence of new donor registrations through the California Organ and Tissue Donor Registry on the local OneLegacy Organ Procurement Organization (OPO) was examined during a 6-year period. Publicly available data from Donate Life America for California were examined for the 6 calendar years of 2009-2014. Performance data from OneLegacy for the same 6 years for organ donors and number of transplants were also examined. The donor designation rate (DDR) was defined as the rate at which new individuals joined the state donor registry as a percentage of all driver licenses and ID cards issued within a calendar year. The total donor designation (TDD) was defined as the sum of the new and existing people who were registered organ donors. Donor designation share (DDS) was the total number of designated donors as a percentage of all residents of the state who were ≥18 years old. The business practices and educational efforts of the OneLegacy OPO were examined as well. In California, from 2009 through 2014, the DDR was 25.5%-28%. When added to the existing donor registrations, the TDD and DDS increased each year from 2009 through 2014. With the current level of growth, it is projected that California will be able to reach a DDS of 50% by 2017. For the OneLegacy OPO, designated donors from the California Organ and Tissue Donor Registry made up 15% of the total donations in 2009, and 39% of the total donations in 2014, increasing by ∼5% each year since 2009. By increasing professionalization and transparency, and widening its educational and training efforts, OneLegacy was able to take advantage of an increasing percentage of donors who were designated donors and to increase the overall number of donors and organs transplanted, becoming one of the largest OPOs in the nation. This can be a model for OPOs in other donor service areas, and it may set the stage for the United States to serve as an example to the global community in the practice of organ donation. Copyright

Elimination of copper in tissues and organs of rainbow trout

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Gaye Dogan

2011-01-01

Full Text Available Copper (Cu elimination was investigated in the tissue and organs of rainbow trout (Oncorhynchus mykiss, Walbaum, 1792, after Cu-free diets exposure. In the current study, fish were fed to satiation on diets containing 0.022 (Group 1; Control, 0.043 (Group 2, 0.123 (Group 3, 0.424 (Group 4 g Cu*kg-1 diet for 60 days before elimination experiment. A total of 288 fish (mean weight 84.28±1.05 g were randomly transferred to 12 fibreglass tanks. The fish were fed the Cu-free diet twice daily, until apparent satiation, during 60 days. Subsequently, the experiment was established for a period of elimination, during which samples were taken at days 15, 30, 45 and 60. Cu concentration in the muscle, gill tissue, digestive system, liver and whole body of fish were determined after 60 days depuration. Cu concentrations in tissues of rainbow trout decreased during depuration period, and the order of Cu elimination in tissue and organs of rainbow trout was: digestive system (73.1 %, then gill (41.1 %, muscle (31.5 % and liver (17.2 % for group 2; digestive system (74.1%, then muscle (65.8%, gill (60.0% and liver (34.6% for group 3; and digestive system (85.8%, then muscle (80.8%, liver (50.5% and less/equal in gill (50.2% for group 4. In statistical analysis, both groups and time were significant factors (P less than 0.05 on elimination rate. Moreover, significant interaction between groups and time were identified on elimination rate. Digestive system showed the fastest elimination rates of Cu at all groups compared with other tissues.

Whole body plastination, intra-organ heterogeneity, and tissue based diagnosis – a survey

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Gunther von Hagens

2018-04-01

Full Text Available  Background: The corpse is the final structural relict of life. Its detailed analysis, the autopsy formed the basis and contributed significantly to our understanding of location, function and interaction of organs in man. Today, autopsies are performed rarely. They have been replaced by radiological in vivo visualization techniques and the analysis of organ excisions and biopsies. Which attributes do whole body preservations possess in this context? Techniques of Whole Body Analysis: In vivo imaging transfers the appearance of body organs and cellular structures in virtual images. The patient’s exposure to X-rays, fundamental particles (electrons, positrons, etc., strong magnetic fields (nuclear resonance, or ultra sounds release the corresponding signals. The obtained images are interpreted in search for local abnormalities such as cancer, acute and chronic infections, inborn errors, hypertrophy or atrophy. Autopsies require the removal and visual inspection of organs shortly after the victim’s death. In addition, tissue probes of suspicious lesions are fixed and microscopically analyzed. The search for gene or protein abnormalities are added dependent upon the clinical history and gross findings. The whole body plastination is performed in separated steps which include fixation, anatomical dissection, forced polymer impregnation, positioning and curing. Organs and other tissue structures can be taken out of the body and separately demonstrated, or aligned and fixed within the body. Additional tissue examinations are possible at this stage, which is followed by hardening and fixation of the still flexible body. Fixation is done with heat, light or gas.   Results and Interpretation: Tissue conservation is a prerequisite to analyze and investigate in diagnosis and forecast of disease occurrence and behaviour. In history, autopsies have opened the door to localize the position and to understand the functions of organs. Today, they have been

Children as donors: a national study to assess procurement of organs and tissues in pediatric intensive care units.

Science.gov (United States)

Siebelink, Marion J; Albers, Marcel J I J; Roodbol, Petrie F; Van de Wiel, Harry B M

2012-12-01

A shortage of size-matched organs and tissues is the key factor limiting transplantation in children. Empirical data on procurement from pediatric donors is sparse. This study investigated donor identification, parental consent, and effectuation rates, as well as adherence to the national protocol. A national retrospective cohort study was conducted in all eight Dutch pediatric intensive care units. Records of deceased children were analyzed by an independent donation officer. Seventy-four (11%) of 683 deceased children were found to be suitable for organ donation and 132 (19%) for tissue donation. Sixty-two (84%) potential organ donors had been correctly identified; the parental consent and effectuation rate was 42%. Sixty-three (48%) potential tissue donors had been correctly identified; the parental consent and effectuation rate was 27%. Correct identification increased with age (logistic regression, organs: P = .024; tissues: P = .011). Although an overall identification rate of 84% of potential organ donors may seem acceptable, the variation observed suggests room for improvement, as does the overall low rate of identification of pediatric tissue donors. Efforts to address the shortage of organs and tissues for transplantation in children should focus on identifying potential donors and on the reasons why parents do not consent. © 2012 The Authors. Transplant International © 2012 European Society for Organ Transplantation.

Two-photon Microscopy and Polarimetry for Assessment of Myocardial Tissue Organization

Science.gov (United States)

Archambault-Wallenburg, Marika

Optical methods can provide useful tissue characterization tools. For this project, two-photon microscopy and polarized light examinations (polarimetry) were used to assess the organizational state of myocardium in healthy, infarcted, and stem-cell regenerated states. Two-photon microscopy visualizes collagen through second-harmonic generation and myocytes through two-photon excitation autofluorescence, providing information on the composition and structure/organization of the tissue. Polarimetry measurements yield a value of linear retardance that can serve as an indicator of tissue anisotropy, and with a dual-projection method, information about the anisotropy axis orientation can also be extracted. Two-photon microscopy results reveal that stem-cell treated tissue retains more myocytes and structure than infarcted myocardium, while polarimetry findings suggest that the injury caused by temporary ligation of a coronary artery is less severe and more diffuse that than caused by a permanent ligation. Both these methods show potential for tissue characterization.

Human colon tissue in organ culture: calcium and multi-mineral-induced mucosal differentiation.

Science.gov (United States)

Dame, Michael K; Veerapaneni, Indiradevi; Bhagavathula, Narasimharao; Naik, Madhav; Varani, James

2011-01-01

We have recently shown that a multi-mineral extract from the marine red algae, Lithothamnion calcareum, suppresses colon polyp formation and inflammation in mice. In the present study, we used intact human colon tissue in organ culture to compare responses initiated by Ca(2+) supplementation versus the multi-mineral extract. Normal human colon tissue was treated for 2 d in culture with various concentrations of calcium or the mineral-rich extract. The tissue was then prepared for histology/immunohistochemistry, and the culture supernatants were assayed for levels of type I procollagen and type I collagen. At higher Ca(2+) concentrations or with the mineral-rich extract, proliferation of epithelial cells at the base and walls of the mucosal crypts was suppressed, as visualized by reduced Ki67 staining. E-cadherin, a marker of differentiation, was more strongly expressed at the upper third of the crypt and at the luminal surface. Treatment with Ca(2+) or with the multi-mineral extract influenced collagen turnover, with decreased procollagen and increased type I collagen. These data suggest that calcium or mineral-rich extract has the capacity to (1) promote differentiation in human colon tissue in organ culture and (2) modulate stromal function as assessed by increased levels of type I collagen. Taken together, these data suggest that human colon tissue in organ culture (supporting in vivo finding in mice) will provide a valuable model for the preclinical assessment of agents that regulate growth and differentiation in the colonic mucosa.

Organ or tissue doses, effective dose and collective effective dose from X-ray diagnosis, in Japan

International Nuclear Information System (INIS)

Murayama, Takashi; Nishizawa, Kanae; Noda, Yutaka; Kumamoto, Yoshikazu; Iwai, Kazuo.

1996-01-01

Effective doses and collective effective doses from X-ray diagnostic examinations were calculated on the basis of the frequency of examinations estimated by a nationwide survey and the organ or tissue doses experimentally determined. The average organ or tissue doses were determined with thermoluminescence dosimeters put at various sites of organs or tissues in an adult and a child phantom. Effective doses (effective dose equivalents) were calculated as the sum of the weighted equivalent doses in all the organs or tissues of the body. As the examples of results, the effective doses per radiographic examination were approximately 7 mGy for male, and 9 mGy for female angiocardiography, and about 3 mGy for barium meal. Annual collective effective dose from X-ray diagnostic examinations in 1986 were about 104 x 10 3 person Sv from radiography and 118 x 10 3 person Sv from fluoroscopy, with the total of 222 x 10 3 person Sv. (author)

Matrix production and organization by endothelial colony forming cells in mechanically strained engineered tissue constructs.

Directory of Open Access Journals (Sweden)

Nicky de Jonge

Full Text Available AIMS: Tissue engineering is an innovative method to restore cardiovascular tissue function by implanting either an in vitro cultured tissue or a degradable, mechanically functional scaffold that gradually transforms into a living neo-tissue by recruiting tissue forming cells at the site of implantation. Circulating endothelial colony forming cells (ECFCs are capable of differentiating into endothelial cells as well as a mesenchymal ECM-producing phenotype, undergoing Endothelial-to-Mesenchymal-transition (EndoMT. We investigated the potential of ECFCs to produce and organize ECM under the influence of static and cyclic mechanical strain, as well as stimulation with transforming growth factor β1 (TGFβ1. METHODS AND RESULTS: A fibrin-based 3D tissue model was used to simulate neo-tissue formation. Extracellular matrix organization was monitored using confocal laser-scanning microscopy. ECFCs produced collagen and also elastin, but did not form an organized matrix, except when cultured with TGFβ1 under static strain. Here, collagen was aligned more parallel to the strain direction, similar to Human Vena Saphena Cell-seeded controls. Priming ECFC with TGFβ1 before exposing them to strain led to more homogenous matrix production. CONCLUSIONS: Biochemical and mechanical cues can induce extracellular matrix formation by ECFCs in tissue models that mimic early tissue formation. Our findings suggest that priming with bioactives may be required to optimize neo-tissue development with ECFCs and has important consequences for the timing of stimuli applied to scaffold designs for both in vitro and in situ cardiovascular tissue engineering. The results obtained with ECFCs differ from those obtained with other cell sources, such as vena saphena-derived myofibroblasts, underlining the need for experimental models like ours to test novel cell sources for cardiovascular tissue engineering.

Expression cartography of human tissues using self organizing maps

Directory of Open Access Journals (Sweden)

Löffler Markus

2011-07-01

Full Text Available Abstract Background Parallel high-throughput microarray and sequencing experiments produce vast quantities of multidimensional data which must be arranged and analyzed in a concerted way. One approach to addressing this challenge is the machine learning technique known as self organizing maps (SOMs. SOMs enable a parallel sample- and gene-centered view of genomic data combined with strong visualization and second-level analysis capabilities. The paper aims at bridging the gap between the potency of SOM-machine learning to reduce dimension of high-dimensional data on one hand and practical applications with special emphasis on gene expression analysis on the other hand. Results The method was applied to generate a SOM characterizing the whole genome expression profiles of 67 healthy human tissues selected from ten tissue categories (adipose, endocrine, homeostasis, digestion, exocrine, epithelium, sexual reproduction, muscle, immune system and nervous tissues. SOM mapping reduces the dimension of expression data from ten of thousands of genes to a few thousand metagenes, each representing a minicluster of co-regulated single genes. Tissue-specific and common properties shared between groups of tissues emerge as a handful of localized spots in the tissue maps collecting groups of co-regulated and co-expressed metagenes. The functional context of the spots was discovered using overrepresentation analysis with respect to pre-defined gene sets of known functional impact. We found that tissue related spots typically contain enriched populations of genes related to specific molecular processes in the respective tissue. Analysis techniques normally used at the gene-level such as two-way hierarchical clustering are better represented and provide better signal-to-noise ratios if applied to the metagenes. Metagene-based clustering analyses aggregate the tissues broadly into three clusters containing nervous, immune system and the remaining tissues

Experience of nurses in the process of donation of organs and tissues for transplant

OpenAIRE

Moraes,Edvaldo Leal de; Santos,Marcelo José dos; Merighi,Miriam Aparecida Barbosa; Massarollo,Maria Cristina Komatsu Braga

2014-01-01

OBJECTIVE: to investigate the meaning of the action of nurses in the donation process to maintain the viability of organs and tissues for transplantation.METHOD: this qualitative study with a social phenomenological approach was conducted through individual interviews with ten nurses of three Organ and Tissue Procurement Services of the city of São Paulo.RESULTS: the experience of the nurses in the donation process was represented by the categories: obstacles experienced in the donation proce...

Physiologically Distributed Loading Patterns Drive the Formation of Zonally Organized Collagen Structures in Tissue-Engineered Meniscus.

Science.gov (United States)

Puetzer, Jennifer L; Bonassar, Lawrence J

2016-07-01

The meniscus is a dense fibrocartilage tissue that withstands the complex loads of the knee via a unique organization of collagen fibers. Attempts to condition engineered menisci with compression or tensile loading alone have failed to reproduce complex structure on the microscale or anatomic scale. Here we show that axial loading of anatomically shaped tissue-engineered meniscus constructs produced spatial distributions of local strain similar to those seen in the meniscus when the knee is loaded at full extension. Such loading drove formation of tissue with large organized collagen fibers, levels of mechanical anisotropy, and compressive moduli that match native tissue. Loading accelerated the development of native-sized and aligned circumferential and radial collagen fibers. These loading patterns contained both tensile and compressive components that enhanced the major biochemical and functional properties of the meniscus, with loading significantly improved glycosaminoglycan (GAG) accumulation 200-250%, collagen accumulation 40-55%, equilibrium modulus 1000-1800%, and tensile moduli 500-1200% (radial and circumferential). Furthermore, this study demonstrates local changes in mechanical environment drive heterogeneous tissue development and organization within individual constructs, highlighting the importance of recapitulating native loading environments. Loaded menisci developed cartilage-like tissue with rounded cells, a dense collagen matrix, and increased GAG accumulation in the more compressively loaded horns, and fibrous collagen-rich tissue in the more tensile loaded outer 2/3, similar to native menisci. Loaded constructs reached a level of organization not seen in any previous engineered menisci and demonstrate great promise as meniscal replacements.

Cytoskeletal Tropomyosin Tm5NM1 Is Required for Normal Excitation–Contraction Coupling in Skeletal Muscle

Science.gov (United States)

Vlahovich, Nicole; Kee, Anthony J.; Van der Poel, Chris; Kettle, Emma; Hernandez-Deviez, Delia; Lucas, Christine; Lynch, Gordon S.; Parton, Robert G.; Gunning, Peter W.

2009-01-01

The functional diversity of the actin microfilaments relies in part on the actin binding protein tropomyosin (Tm). The muscle-specific Tms regulate actin-myosin interactions and hence contraction. However, there is less known about the roles of the numerous cytoskeletal isoforms. We have shown previously that a cytoskeletal Tm, Tm5NM1, defines a Z-line adjacent cytoskeleton in skeletal muscle. Recently, we identified a second cytoskeletal Tm in this region, Tm4. Here we show that Tm4 and Tm5NM1 define separate actin filaments; the former associated with the terminal sarcoplasmic reticulum (SR) and other tubulovesicular structures. In skeletal muscles of Tm5NM1 knockout (KO) mice, Tm4 localization was unchanged, demonstrating the specificity of the membrane association. Tm5NM1 KO muscles exhibit potentiation of T-system depolarization and decreased force rundown with repeated T-tubule depolarizations consistent with altered T-tubule function. These results indicate that a Tm5NM1-defined actin cytoskeleton is required for the normal excitation–contraction coupling in skeletal muscle. PMID:19005216

Cytoskeletal tropomyosin Tm5NM1 is required for normal excitation-contraction coupling in skeletal muscle.

Science.gov (United States)

Vlahovich, Nicole; Kee, Anthony J; Van der Poel, Chris; Kettle, Emma; Hernandez-Deviez, Delia; Lucas, Christine; Lynch, Gordon S; Parton, Robert G; Gunning, Peter W; Hardeman, Edna C

2009-01-01

The functional diversity of the actin microfilaments relies in part on the actin binding protein tropomyosin (Tm). The muscle-specific Tms regulate actin-myosin interactions and hence contraction. However, there is less known about the roles of the numerous cytoskeletal isoforms. We have shown previously that a cytoskeletal Tm, Tm5NM1, defines a Z-line adjacent cytoskeleton in skeletal muscle. Recently, we identified a second cytoskeletal Tm in this region, Tm4. Here we show that Tm4 and Tm5NM1 define separate actin filaments; the former associated with the terminal sarcoplasmic reticulum (SR) and other tubulovesicular structures. In skeletal muscles of Tm5NM1 knockout (KO) mice, Tm4 localization was unchanged, demonstrating the specificity of the membrane association. Tm5NM1 KO muscles exhibit potentiation of T-system depolarization and decreased force rundown with repeated T-tubule depolarizations consistent with altered T-tubule function. These results indicate that a Tm5NM1-defined actin cytoskeleton is required for the normal excitation-contraction coupling in skeletal muscle.

Transplantation of Bioprinted Tissues and Organs: Technical and Clinical Challenges and Future Perspectives.

Science.gov (United States)

Ravnic, Dino J; Leberfinger, Ashley N; Koduru, Srinivas V; Hospodiuk, Monika; Moncal, Kazim K; Datta, Pallab; Dey, Madhuri; Rizk, Elias; Ozbolat, Ibrahim T

2017-07-01

: Three-dimensional (3D) bioprinting is a revolutionary technology in building living tissues and organs with precise anatomic control and cellular composition. Despite the great progress in bioprinting research, there has yet to be any clinical translation due to current limitations in building human-scale constructs, which are vascularized and readily implantable. In this article, we review the current limitations and challenges in 3D bioprinting, including in situ techniques, which are one of several clinical translational models to facilitate the application of this technology from bench to bedside. A detailed discussion is made on the technical barriers in the fabrication of scalable constructs that are vascularized, autologous, functional, implantable, cost-effective, and ethically feasible. Clinical considerations for implantable bioprinted tissues are further expounded toward the correction of end-stage organ dysfunction and composite tissue deficits.

Registration for deceased organ and tissue donation among Ontario immigrants: a population-based cross-sectional study.

Science.gov (United States)

Li, Alvin Ho-Ting; Lam, Ngan N; Dhanani, Sonny; Weir, Matthew; Prakash, Versha; Kim, Joseph; Knoll, Greg; Garg, Amit X

2016-01-01

Canada has low rates of deceased organ and tissue donation. Immigrants to Canada may differ in their registered support for deceased organ donation based on their country of origin. We used linked administrative databases in Ontario (about 11 million residents aged ≥ 16 yr) to study the proportion of immigrants and long-term residents registered for deceased organ and tissue donation as of October 2013. We used modified Poisson regression to identify and quantify predictors of donor registration. Compared with long-term residents ( n = 9 244 570), immigrants ( n = 1 947 646) were much less likely to register for deceased organ and tissue donation (11.9% v. 26.5%). Immigrants from the United States, Australia and New Zealand had the highest registration rate (40.0%), whereas immigrants with the lowest registration rates were from Eastern Europe and Central Asia (9.4%), East Asia and Pacific (8.4%) and sub-Saharan Africa (7.9%). The largest numbers of unregistered immigrants were from India ( n = 202 548), China ( n = 186 678) and the Philippines ( n = 125 686). Characteristics among the immigrant population associated with a higher likelihood of registration included economic immigrant status, living in a rural area (population speak English and French, and more years residing in Canada. Immigrants in Ontario were less likely to register for deceased organ and tissue donation than long-term residents. There is a need to better understand reasons for lower registration rates among Canadian immigrants and to create culture-sensitive materials to build support for deceased organ and tissue donation.

Spatial organization of adhesion: force-dependent regulation and function in tissue morphogenesis

OpenAIRE

Papusheva, Ekaterina; Heisenberg, Carl-Philipp

2010-01-01

The Heisenberg laboratory reviews the spatial organization of signalling complexes at cell–matrix and cell–cell contact sites and its impact on cell integrity, cellular polarity and tissue morphogenesis.

The strength of a calcified tissue depends in part on the molecular structure and organization of its constituent mineral crystals in their organic matrix

Science.gov (United States)

Landis, W. J.

1995-01-01

High-voltage electron-microscopic tomographic (3D) studies of the ultrastructural interaction between mineral and organic matrix in a variety of calcified tissues reveal different crystal structural and organizational features in association with their respective organic matrices. In brittle or weak pathologic or ectopic calcifications, including examples of osteogenesis imperfecta, calciphylaxis, calcergy, and dermatomyositis, hydroxyapatite crystals occur in various sizes and shapes and are oriented and aligned with respect to collagen in a manner which is distinct from that found in normal calcified tissues. A model of collagen-mineral interaction is proposed which may account for the observed crystal structures and organization. The results indicate that the ultimate strength, support, and other mechanical properties provided by a calcified tissue are dependent in part upon the molecular structure and arrangement of its constituent mineral crystals within their organic matrix.

Reconstruction of structure and function in tissue engineering of solid organs: Toward simulation of natural development based on decellularization.

Science.gov (United States)

Zheng, Chen-Xi; Sui, Bing-Dong; Hu, Cheng-Hu; Qiu, Xin-Yu; Zhao, Pan; Jin, Yan

2018-04-27

Failure of solid organs, such as the heart, liver, and kidney, remains a major cause of the world's mortality due to critical shortage of donor organs. Tissue engineering, which uses elements including cells, scaffolds, and growth factors to fabricate functional organs in vitro, is a promising strategy to mitigate the scarcity of transplantable organs. Within recent years, different construction strategies that guide the combination of tissue engineering elements have been applied in solid organ tissue engineering and have achieved much progress. Most attractively, construction strategy based on whole-organ decellularization has become a popular and promising approach, because the overall structure of extracellular matrix can be well preserved. However, despite the preservation of whole structure, the current constructs derived from decellularization-based strategy still perform partial functions of solid organs, due to several challenges, including preservation of functional extracellular matrix structure, implementation of functional recellularization, formation of functional vascular network, and realization of long-term functional integration. This review overviews the status quo of solid organ tissue engineering, including both advances and challenges. We have also put forward a few techniques with potential to solve the challenges, mainly focusing on decellularization-based construction strategy. We propose that the primary concept for constructing tissue-engineered solid organs is fabricating functional organs based on intact structure via simulating the natural development and regeneration processes. Copyright © 2018 John Wiley & Sons, Ltd.

High Dietary Fructose: Direct or Indirect Dangerous Factors Disturbing Tissue and Organ Functions.

Science.gov (United States)

Zhang, Dong-Mei; Jiao, Rui-Qing; Kong, Ling-Dong

2017-03-29

High dietary fructose is a major contributor to insulin resistance and metabolic syndrome, disturbing tissue and organ functions. Fructose is mainly absorbed into systemic circulation by glucose transporter 2 (GLUT2) and GLUT5, and metabolized in liver to produce glucose, lactate, triglyceride (TG), free fatty acid (FFA), uric acid (UA) and methylglyoxal (MG). Its extrahepatic absorption and metabolism also take place. High levels of these metabolites are the direct dangerous factors. During fructose metabolism, ATP depletion occurs and induces oxidative stress and inflammatory response, disturbing functions of local tissues and organs to overproduce inflammatory cytokine, adiponectin, leptin and endotoxin, which act as indirect dangerous factors. Fructose and its metabolites directly and/or indirectly cause oxidative stress, chronic inflammation, endothelial dysfunction, autophagy and increased intestinal permeability, and then further aggravate the metabolic syndrome with tissue and organ dysfunctions. Therefore, this review addresses fructose-induced metabolic syndrome, and the disturbance effects of direct and/or indirect dangerous factors on the functions of liver, adipose, pancreas islet, skeletal muscle, kidney, heart, brain and small intestine. It is important to find the potential correlations between direct and/or indirect risk factors and healthy problems under excess dietary fructose consumption.

High Dietary Fructose: Direct or Indirect Dangerous Factors Disturbing Tissue and Organ Functions

Directory of Open Access Journals (Sweden)

Dong-Mei Zhang

2017-03-01

Full Text Available High dietary fructose is a major contributor to insulin resistance and metabolic syndrome, disturbing tissue and organ functions. Fructose is mainly absorbed into systemic circulation by glucose transporter 2 (GLUT2 and GLUT5, and metabolized in liver to produce glucose, lactate, triglyceride (TG, free fatty acid (FFA, uric acid (UA and methylglyoxal (MG. Its extrahepatic absorption and metabolism also take place. High levels of these metabolites are the direct dangerous factors. During fructose metabolism, ATP depletion occurs and induces oxidative stress and inflammatory response, disturbing functions of local tissues and organs to overproduce inflammatory cytokine, adiponectin, leptin and endotoxin, which act as indirect dangerous factors. Fructose and its metabolites directly and/or indirectly cause oxidative stress, chronic inflammation, endothelial dysfunction, autophagy and increased intestinal permeability, and then further aggravate the metabolic syndrome with tissue and organ dysfunctions. Therefore, this review addresses fructose-induced metabolic syndrome, and the disturbance effects of direct and/or indirect dangerous factors on the functions of liver, adipose, pancreas islet, skeletal muscle, kidney, heart, brain and small intestine. It is important to find the potential correlations between direct and/or indirect risk factors and healthy problems under excess dietary fructose consumption.

Modelling organs, tissues, cells and devices using Matlab and Comsol multiphysics

CERN Document Server

Dokos, Socrates

2017-01-01

This book presents a theoretical and practical overview of computational modeling in bioengineering, focusing on a range of applications including electrical stimulation of neural and cardiac tissue, implantable drug delivery, cancer therapy, biomechanics, cardiovascular dynamics, as well as fluid-structure interaction for modelling of organs, tissues, cells and devices. It covers the basic principles of modeling and simulation with ordinary and partial differential equations using MATLAB and COMSOL Multiphysics numerical software. The target audience primarily comprises postgraduate students and researchers, but the book may also be beneficial for practitioners in the medical device industry.

A method for the determination of potassium concentration in organic tissue samples

International Nuclear Information System (INIS)

Maciel, A.C.A.

1976-12-01

An original method has been developed to detect small variations of potassium in several samples of organic tissue. These variations are relative to elements that are biologically representative, such as carbon, oxygen, and nitrogen. The samples are irradiated with a beam of protons from a Van de Graaff accelerator (4MV). Vacancies are created in the K-shell of potassium, and x-rays are emitted when these vacancies are filled with outer electrons. These X-rays and the protons elastically scattered by the nuclei of carbon, nitrogen and oxygen are detected and their energy spectra are analysed by computer programs especially elaborated for this purpose. A technique for routine preparation of samples in the laboratory was developed including the production of aluminum support layers, and the preparation of organic tissue samples with a low temperature microtome. The unique features of this method are that it does not destroy the tissue, permitting further analysis with the microscope, and the normalization of the amount of potassium using other elements (C,O,N) instead of the total mass of the sample. (Author) [pt

Concise review: can the intrinsic power of branching morphogenesis be used for engineering epithelial tissues and organs?

Science.gov (United States)

Nigam, Sanjay K

2013-12-01

Branching morphogenesis is critical to the development of organs such as kidney, lung, mammary gland, prostate, pancreas, and salivary gland. Essentially, an epithelial bud becomes an iterative tip-stalk generator (ITSG) able to form a tree of branching ducts and/or tubules. In different organs, branching morphogenesis is governed by similar sets of genes. Epithelial branching has been recapitulated in vitro (or ex vivo) using three-dimensional cell culture and partial organ culture systems, and several such systems relevant to kidney tissue engineering are discussed here. By adapting systems like these it may be possible to harness the power inherent in the ITSG program to propagate and engineer epithelial tissues and organs. It is also possible to conceive of a universal ITSG capable of propagation that may, by recombination with organ-specific mesenchymal cells, be used for engineering many organ-like tissues similar to the organ from which the mesenchyme cells were derived, or toward which they are differentiated (from stem cells). The three-dimensional (3D) branched epithelial structure could act as a dynamic branching cellular scaffold to establish the architecture for the rest of the tissue. Another strategy-that of recombining propagated organ-specific ITSGs in 3D culture with undifferentiated mesenchymal stem cells-is also worth exploring. If feasible, such engineered tissues may be useful for the ex vivo study of drug toxicity, developmental biology, and physiology in the laboratory. Over the long term, they have potential clinical applications in the general fields of transplantation, regenerative medicine, and bioartificial medical devices to aid in the treatment of chronic kidney disease, diabetes, and other diseases.

Profile of effective donors from organ and tissue procurement services

Science.gov (United States)

Rodrigues, Simey de Lima Lopes; Ferraz Neto, Jose Ben-Hur de Escobar; Sardinha, Luiz Antonio da Costa; Araujo, Sebastião; Zambelli, Helder Jose Lessa; Boin, Ilka de Fátima Santana Ferreira; Athayde, Maria Valeria de Omena; Montone, Eliete Bombarda Bachega; Panunto, Marcia Raquel

2014-01-01

Objective To characterize the profile of effective organ and tissue donors and to understand which organs and tissues were donated for transplantation. Methods This was a quantitative, descriptive, exploratory, retrospective study that analyzed clinical data from 305 donors between January 2006 to December 2010. The data were then analyzed using descriptive analyses, generating frequency tables, measures of position (mean, minimum and maximum) and measures of dispersion (standard deviation) for data that was social and clinical in nature. Results There was an overall predominance of white (72%) and male (55%) individuals between the ages of 41 and 60 years (44%). The primary cause of brain death was cerebrovascular accident (55%). In the patient history, 31% of the patients were classified as overweight, 27% as hypertensive and only 4.3% as having diabetes mellitus. Vasoactive drugs were used in 92.7% of the donors, and the main drug of choice was noradrenaline (81.6%). Hyperglycemia and hypernatremia were diagnosed in 78% and 71% of the donors, respectively. Conclusion Significant hemodynamic changes were found, and the results indicate that the use of vasoactive drugs was the main strategy used to control these changes. Furthermore, most donors presented with hyperglycemia and hypernatremia, which were frequently reported in association with brain death. The persistent nature of these findings suggests that the organ donors were inadequately maintained. PMID:24770685

Medical applications of membranes: Drug delivery, artificial organs and tissue engineering

NARCIS (Netherlands)

Stamatialis, Dimitrios; Papenburg, B.J.; Girones nogue, Miriam; Saiful, S.; Bettahalli Narasimha, M.S.; Schmitmeier, Stephanie; Wessling, Matthias

2008-01-01

This paper covers the main medical applications of artificial membranes. Specific attention is given to drug delivery systems, artificial organs and tissue engineering which seem to dominate the interest of the membrane community this period. In all cases, the materials, methods and the current

Cause marketing for tissue and organ donation to increase public awareness

International Nuclear Information System (INIS)

Strong, M.; Neely, D.; Warnack, K.; Willits, M.; Yriondo, L.

1999-01-01

Today the science of marketing is being applied more and more to increase the rate of tissue and organ donation in the United States. To benefit from the proven tools and techniques of successful marketing in the for-profit world transplantation agencies across the country are turning to integrated marketing communications strategies and strategic partnerships to help achieve their goals.The methods used in cause marketing include: Establishing clear and measurable outcomes and goals; building a marketing plan and timeline to achieve the goals; gathering resources (funding, personnel, organizations, partnerships) to execute the plan, implementation, and measurement of outcomes. This session will review the Tissue and Organ Donation campaign implemented in the Northwest and will touch on the national awareness program developed by United Network for Organ Sharing (UNOS) in the United States. Segments of the Northwest's integrated campaign will include market segmentation strategies and targeted marketing, campaign development, public service advertising and public education campaigns. Media utilized include print, bus signs and billboards, broadcast (radio and TV), video and the internet. Strategies include public service advertising, paid advertising through sponsorships, direct mail, workshops and public speaking. The success of traditional product marketing can be achieved in cause marketing with a long-term, focused public education campaign. The potential benefit to the international community warrants exploration of similar strategies to overcome cultural resistance to life saving transplantation

Acellular organ scaffolds for tumor tissue engineering

Science.gov (United States)

Guller, Anna; Trusova, Inna; Petersen, Elena; Shekhter, Anatoly; Kurkov, Alexander; Qian, Yi; Zvyagin, Andrei

2015-12-01

Rationale: Tissue engineering (TE) is an emerging alternative approach to create models of human malignant tumors for experimental oncology, personalized medicine and drug discovery studies. Being the bottom-up strategy, TE provides an opportunity to control and explore the role of every component of the model system, including cellular populations, supportive scaffolds and signalling molecules. Objectives: As an initial step to create a new ex vivo TE model of cancer, we optimized protocols to obtain organ-specific acellular matrices and evaluated their potential as TE scaffolds for culture of normal and tumor cells. Methods and results: Effective decellularization of animals' kidneys, ureter, lungs, heart, and liver has been achieved by detergent-based processing. The obtained scaffolds demonstrated biocompatibility and growthsupporting potential in combination with normal (Vero, MDCK) and tumor cell lines (C26, B16). Acellular scaffolds and TE constructs have been characterized and compared with morphological methods. Conclusions: The proposed methodology allows creation of sustainable 3D tumor TE constructs to explore the role of organ-specific cell-matrix interaction in tumorigenesis.

Organ and tissue level properties are more sensitive to age than osteocyte lacunar characteristics in rat cortical bone

DEFF Research Database (Denmark)

Wittig, Nina; Bach-Gansmo, Fiona Linnea; Birkbak, Mie Elholm

2016-01-01

orientation with animal age. Hence, the evolution of organ and tissue level properties with age in rat cortical bone is not accompanied by related changes in osteocyte lacunar properties. This suggests that bone microstructure and bone matrix material properties and not the geometric properties...... of bone on the organ and tissue level, whereas features on the nano- and micrometer scale are much less explored. We investigated the age-related development of organ and tissue level bone properties such as bone volume, bone mineral density, and load to fracture and correlated these with osteocyte...

Quantum dots versus organic fluorophores in fluorescent deep-tissue imaging--merits and demerits.

Science.gov (United States)

Bakalova, Rumiana; Zhelev, Zhivko; Gadjeva, Veselina

2008-12-01

The use of fluorescence in deep-tissue imaging is rapidly expanding in last several years. The progress in fluorescent molecular probes and fluorescent imaging techniques gives an opportunity to detect single cells and even molecular targets in live organisms. The highly sensitive and high-speed fluorescent molecular sensors and detection devices allow the application of fluorescence in functional imaging. With the development of novel bright fluorophores based on nanotechnologies and 3D fluorescence scanners with high spatial and temporal resolution, the fluorescent imaging has a potential to become an alternative of the other non-invasive imaging techniques as magnetic resonance imaging, positron-emission tomography, X-ray, computing tomography. The fluorescent imaging has also a potential to give a real map of human anatomy and physiology. The current review outlines the advantages of fluorescent nanoparticles over conventional organic dyes in deep-tissue imaging in vivo and defines the major requirements to the "perfect fluorophore". The analysis proceeds from the basic principles of fluorescence and major characteristics of fluorophores, light-tissue interactions, and major limitations of fluorescent deep-tissue imaging. The article is addressed to a broad readership - from specialists in this field to university students.

DMPD: Adipose tissue as an immunological organ: Toll-like receptors, C1q/TNFs andCTRPs. [Dynamic Macrophage Pathway CSML Database

Lifescience Database Archive (English)

Full Text Available 17681884 Adipose tissue as an immunological organ: Toll-like receptors, C1q/TNFs an...ng) (.svg) (.html) (.csml) Show Adipose tissue as an immunological organ: Toll-like receptors, C1q/TNFs andC...TRPs. PubmedID 17681884 Title Adipose tissue as an immunological organ: Toll-like

Legal Issues Related to Donation of Organs, Tissues and Cells of Human Origin

Directory of Open Access Journals (Sweden)

Gabriela Mironov

2010-06-01

Full Text Available Scientific developments, positive changes in attitude of the man and the new legal framework allow the donation of organs, tissues and cells of human origin. In this context it is necessary to clarifywhether the donation covered by the special law is, legally, one and the same as that covered by the Romanian Civil Code in force and qualified the successor’s right to accept or reject late withdrawals for transplantation. The right to life and physical integrity is personal patrimony; it is a subjective civil right that has no economic content and it cannot be measured in money. Consequently, the content of these rights can not be expressed in money, the property does not belong to their owner. Given the above view, "the right of disposal" to donation of organs, tissues and cells of human origin is an attribute of ownership, right to life and physical integrity, as a personal right that is an intimate attribute patrimonial related to the person’s right to dispose of his body as it wishes, within the law. Addressing these issues it is necessary to clarify the legal consequences of donating organs, tissues and cells of human origin, considering that medical activities are becoming more numerous.

The rapid manufacture of uniform composite multicellular-biomaterial micropellets, their assembly into macroscopic organized tissues, and potential applications in cartilage tissue engineering.

Science.gov (United States)

Babur, Betul Kul; Kabiri, Mahboubeh; Klein, Travis Jacob; Lott, William B; Doran, Michael Robert

2015-01-01

We and others have published on the rapid manufacture of micropellet tissues, typically formed from 100-500 cells each. The micropellet geometry enhances cellular biological properties, and in many cases the micropellets can subsequently be utilized as building blocks to assemble complex macrotissues. Generally, micropellets are formed from cells alone, however when replicating matrix-rich tissues such as cartilage it would be ideal if matrix or biomaterials supplements could be incorporated directly into the micropellet during the manufacturing process. Herein we describe a method to efficiently incorporate donor cartilage matrix into tissue engineered cartilage micropellets. We lyophilized bovine cartilage matrix, and then shattered it into microscopic pieces having average dimensions manufacture of thousands of replica composite micropellets, with each micropellet having a material/CD core and a cellular surface. This micropellet organization enabled the rapid bulking up of the micropellet core matrix content, and left an adhesive cellular outer surface. This morphological organization enabled the ready assembly of the composite micropellets into macroscopic tissues. Generically, this is a versatile method that enables the rapid and uniform integration of biomaterials into multicellular micropellets that can then be used as tissue building blocks. In this study, the addition of CD resulted in an approximate 8-fold volume increase in the micropellets, with the donor matrix functioning to contribute to an increase in total cartilage matrix content. Composite micropellets were readily assembled into macroscopic cartilage tissues; the incorporation of CD enhanced tissue size and matrix content, but did not enhance chondrogenic gene expression.

Certification of the methylmercury content in SRM 2977 mussel tissue (organic contaminants and trace elements) and SRM 1566b oyster tissue.

Science.gov (United States)

Tutschku, S; Schantz, M M; Horvat, M; Logar, M; Akagi, H; Emons, H; Levenson, M; Wise, S A

2001-02-01

The methylmercury content in two new marine bivalve mollusk tissue Standard Reference Materials (SRMs) has been certified using results of analyses from the National Institute of Standards and Technology (NIST) and two other laboratories. The certified concentrations of methylmercury were established based on the results from four and six different (independent) analytical methods, respectively, for SRM 1566b Oyster Tissue (13.2 +/- 0.7 microg/kg) and SRM 2977 Mussel Tissue (organic contaminants and trace elements) (36.2 +/- 1.7 microg/kg). The certified concentration of methylmercury in SRM 1566b is among the lowest in any certified reference material (CRM).

High-resolution magnetic resonance imaging tracks changes in organ and tissue mass in obese and aging rats.

Science.gov (United States)

Tang, Haiying; Vasselli, Joseph R; Wu, Ed X; Boozer, Carol N; Gallagher, Dympna

2002-03-01

Magnetic resonance imaging (MRI) has the ability to discriminate between various soft tissues in vivo. Whole body, specific organ, total adipose tissue (TAT), intra-abdominal adipose tissue (IAAT), and skeletal muscle (SM) weights determined by MRI were compared with weights determined by dissection and chemical analysis in two studies with male Sprague-Dawley rats. A 4.2-T MRI machine acquired high-resolution, in vivo, longitudinal whole body images of rats as they developed obesity or aged. Weights of the whole body and specific tissues were determined using computer image analysis software, including semiautomatic segmentation algorithms for volume calculations. High correlations were found for body weight (r = 0.98), TAT (r = 0.99), and IAAT (r = 0.98) between MRI and dissection and chemical analyses. MRI estimated the weight of the brain, kidneys, and spleen with high accuracy (r > 0.9), but overestimated IAAT, SM, and liver volumes. No differences were detected in organ weights using MRI and dissection measurements. Longitudinal MRI measurements made during the development of obesity and aging accurately represented changes in organ and tissue mass.

Balancing hope and despair at the end of life: The contribution of organ and tissue donation.

Science.gov (United States)

Walker, Wendy; Sque, Magi

2016-04-01

Concern for the grieving family can moderate the intentions of critical care staff to advocate deceased organ and tissue donation. Conversely, benevolent actions may provoke distress through missed opportunities to save or transform lives. This article provides insight into the perceived benefits of organ and tissue donation for grieving families who experienced end-of-life care in the intensive care unit. Data were collected via semistructured, face-to-face or telephone interviews with 43 participants from 31 donor families. Audio recordings were transcribed verbatim and subjected to qualitative content analysis. The study findings affirmed the importance of person-centered end-of-life care. Donor families shared examples of good-quality care and communication that contained the hallmarks of compassion, respect, dignity, and choice. We uncovered a trajectory of hope and despair in which the option of organ and tissue donation appeared to give meaning to the life and death of the deceased person and was comforting to some families in their bereavement. Our study findings underlined the significance of donation decision making for grieving families. Organ and tissue donation has the potential to balance hope and despair at the end of life when the wishes of the dying, deceased, and bereaved are fulfilled. Copyright © 2015 Elsevier Inc. All rights reserved.

Absolute quantification method and validation of airborne snow crab allergen tropomyosin using tandem mass spectrometry

International Nuclear Information System (INIS)

Rahman, Anas M. Abdel; Lopata, Andreas L.; Randell, Edward W.; Helleur, Robert J.

2010-01-01

Measuring the levels of the major airborne allergens of snow crab in the workplace is very important in studying the prevalence of crab asthma in workers. Previously, snow crab tropomyosin (SCTM) was identified as the major aeroallergen in crab plants and a unique signature peptide was identified for this protein. The present study advances our knowledge on aeroallergens by developing a method of quantification of airborne SCTM by using isotope dilution mass spectrometry. Liquid chromatography tandem mass spectrometry was developed for separation and analysis of the signature peptides. The tryptic digestion conditions were optimized to accomplish complete digestion. The validity of the method was studied using international conference on harmonization protocol, Where 2-9% for CV (precision) and 101-110% for accuracy, at three different levels of quality control. Recovery of the spiked protein from PTFE and TopTip filters was measured to be 99% and 96%, respectively. To further demonstrate the applicability and the validity of the method for real samples, 45 kg of whole snow crab were processed in an enclosed (simulated) crab processing line and air samples were collected. The levels of SCTM ranged between 0.36-3.92 μg m -3 and 1.70-2.31 μg m -3 for butchering and cooking stations, respectively.

Absolute quantification method and validation of airborne snow crab allergen tropomyosin using tandem mass spectrometry

Energy Technology Data Exchange (ETDEWEB)

Rahman, Anas M. Abdel, E-mail: anasar@mun.ca [Department of Chemistry, Memorial University of Newfoundland, St. John' s, Newfoundland A1B 3X7 (Canada); Lopata, Andreas L. [School of Applied Science, Marine Biomedical Sciences and Health Research Group, RMIT University, Bundoora, 3083 Victoria (Australia); Randell, Edward W. [Department of Laboratory Medicine, Memorial University of Newfoundland, Eastern Health, St. John' s, Newfoundland and Labrador A1B 3V6 (Canada); Helleur, Robert J. [Department of Chemistry, Memorial University of Newfoundland, St. John' s, Newfoundland A1B 3X7 (Canada)

2010-11-29

Measuring the levels of the major airborne allergens of snow crab in the workplace is very important in studying the prevalence of crab asthma in workers. Previously, snow crab tropomyosin (SCTM) was identified as the major aeroallergen in crab plants and a unique signature peptide was identified for this protein. The present study advances our knowledge on aeroallergens by developing a method of quantification of airborne SCTM by using isotope dilution mass spectrometry. Liquid chromatography tandem mass spectrometry was developed for separation and analysis of the signature peptides. The tryptic digestion conditions were optimized to accomplish complete digestion. The validity of the method was studied using international conference on harmonization protocol, Where 2-9% for CV (precision) and 101-110% for accuracy, at three different levels of quality control. Recovery of the spiked protein from PTFE and TopTip filters was measured to be 99% and 96%, respectively. To further demonstrate the applicability and the validity of the method for real samples, 45 kg of whole snow crab were processed in an enclosed (simulated) crab processing line and air samples were collected. The levels of SCTM ranged between 0.36-3.92 {mu}g m{sup -3} and 1.70-2.31 {mu}g m{sup -3} for butchering and cooking stations, respectively.

Production of high quality brain-derived neurotrophic factor (BDNF) and tropomyosin receptor kinase B (TrkB) RNA from isolated populations of rat spinal cord motor neurons obtained by Laser Capture Microdissection (LCM).

Science.gov (United States)

Mehta, Prachi; Premkumar, Brian; Morris, Renée

2016-08-03

The mammalian central nervous system (CNS) is composed of multiple cellular elements, making it challenging to segregate one particular cell type to study their gene expression profile. For instance, as motor neurons represent only 5-10% of the total cell population of the spinal cord, meaningful transcriptional analysis on these neurons is almost impossible to achieve from homogenized spinal cord tissue. A major challenge faced by scientists is to obtain good quality RNA from small amounts of starting material. In this paper, we used Laser Capture Microdissection (LCM) techniques to identify and isolate spinal cord motor neurons. The present analysis revealed that perfusion with paraformaldehyde (PFA) does not alter RNA quality. RNA integrity numbers (RINs) of tissue samples from rubrospinal tract (RST)-transected, intact spinal cord or from whole spinal cord homogenate were all above 8, which indicates intact, high-quality RNA. Levels of mRNA for brain-derived neurotrophic factor (BDNF) or for its tropomyosin receptor kinase B (TrkB) were not affected by rubrospinal tract (RST) transection, a surgical procedure that deprive motor neurons from one of their main supraspinal input. The isolation of pure populations of neurons with LCM techniques allows for robust transcriptional characterization that cannot be achieved with spinal cord homogenates. Such preparations of pure population of motor neurons will provide valuable tools to advance our understanding of the molecular mechanisms underlying spinal cord injury and neuromuscular diseases. In the near future, LCM techniques might be instrumental to the success of gene therapy for these debilitating conditions. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Automatic segmentation of abdominal organs and adipose tissue compartments in water-fat MRI: Application to weight-loss in obesity.

Science.gov (United States)

Shen, Jun; Baum, Thomas; Cordes, Christian; Ott, Beate; Skurk, Thomas; Kooijman, Hendrik; Rummeny, Ernst J; Hauner, Hans; Menze, Bjoern H; Karampinos, Dimitrios C

2016-09-01

To develop a fully automatic algorithm for abdominal organs and adipose tissue compartments segmentation and to assess organ and adipose tissue volume changes in longitudinal water-fat magnetic resonance imaging (MRI) data. Axial two-point Dixon images were acquired in 20 obese women (age range 24-65, BMI 34.9±3.8kg/m(2)) before and after a four-week calorie restriction. Abdominal organs, subcutaneous adipose tissue (SAT) compartments (abdominal, anterior, posterior), SAT regions along the feet-head direction and regional visceral adipose tissue (VAT) were assessed by a fully automatic algorithm using morphological operations and a multi-atlas-based segmentation method. The accuracy of organ segmentation represented by Dice coefficients ranged from 0.672±0.155 for the pancreas to 0.943±0.023 for the liver. Abdominal SAT changes were significantly greater in the posterior than the anterior SAT compartment (-11.4%±5.1% versus -9.5%±6.3%, pabdominal adipose tissue and organ segmentation, and allowed the detection of SAT and VAT subcompartments changes during weight loss. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Bioprinting of Micro-Organ Tissue Analog for Drug Metabolism Study

Science.gov (United States)

Sun, Wei

An evolving application of tissue engineering is to develop in vitro 3D cell/tissue models for drug screening and pharmacological study. In order to test in space, these in vitro models are mostly manufactured through micro-fabrication techniques and incorporate living cells with MEMS or microfluidic devices. These cell-integrated microfluidic devices, or referred as microorgans, are effective in furnishing reliable and inexpensive drug metabolism and toxicity studies [1-3]. This paper will present an on-going research collaborated between Drexel University and NASA JSC Radiation Physics Laboratory for applying a direct cell printing technique to freeform fabrication of 3D liver tissue analog in drug metabolism study. The paper will discuss modeling, design, and solid freeform fabrication of micro-fluidic flow patterns and bioprinting of 3D micro-liver chamber that biomimics liver physiological microenvironment for enhanced drug metabolization. Technical details to address bioprinting of 3D liver tissue analog, integration with a microfluidic device, and basic drug metabolism study for NASA's interests will presented. 1. Holtorf H. Leslie J. Chang R, Nam J, Culbertson C, Sun W, Gonda S, "Development of a Three-Dimensional Tissue-on-a-Chip Micro-Organ Device for Pharmacokinetic Analysis", the 47th Annual Meeting of the American Society for Cell Biology, Washington, DC, December 1-5, 2007. 2. Chang, R., Nam, J., Culbertson C., Holtorf, H., Jeevarajan, A., Gonda, S. and Sun, W., "Bio-printing and Modeling of Flow Patterns for Cell Encapsulated 3D Liver Chambers For Pharmacokinetic Study", TERMIS North America 2007 Conference and Exposition, Westin Harbour Castle, Toronto, Canada, June 13-16, 2007. 3.Starly, B., Chang, R., Sun, W., Culbertson, C., Holtorf, H. and Gonda, S., "Bioprinted Tissue-on-chip Application for Pharmacokinetic Studies", Proceedings of World Congress on Tissue Engineering and Regenerative Medicine, Pittsburgh, PA, USA, April 24-27, 2006.

Alpha-particle doses to human organs and tissues from internally-deposited 226Ra and 228Ra

International Nuclear Information System (INIS)

Keane, A.T.; Schlenker, R.A.

1981-01-01

Estimation of radiation doses to the soft tissues from internally-deposited 226 Ra and 228 Ra is relevant to an investigation of soft-tissue malignancies in radium-exposed persons being conducted at the Center for Human Radiobiology. Alpha-particle doses in a 50-year period following a single injection of 226 Ra or 228 Ra are presented for 31 soft tissues and organs of the adult human. The dose estimates were derived from the ICRP alkaline earth model fitted to data on retention of 226 Ra in soft tissues and bone, combined with reported ratios of 226 Ra to Ca in soft tissue and bone at natural levels and the distribution of Ca in the tissues of Reference Man (ICRP23). The median of the 31 organ and tissue doses from the α-particles of 226 Ra itself is 0.08 rad per injected μCi. An additional average dose of 0.01 rad per μCi 226 Ra daughter products produced in soft tissue or transferred from bone to soft tissue. Soft-tissue doses from α-particles of the 228 Ra decay series are about six times those from 226 Ra α-particles for equal injected activities of 228 Ra and 226 Ra, with the assumption that 228 Ra daughter products do not transfer from the organ in which they are produced. The 50-year dose to the red marrow of bone from α-particles originating in bone is 0.55 rad per μCi 226 Ra injected and 1.0 rad per μCi 228 Ra injected. For ingestion by dial painters of luminous compound containg 226 Ra or 228 Ra with a daughter-to-parent activity ratio of 0.5, the dose to the mucosal alyer of the lower large intestine from α-particles originating in the gut contents is about 0.1 rad per μCi systemic intake of 226 Ra or 228 Ra

The interaction between tropomyosin-related kinase B receptors and serine kinases modulates acetylcholine release in adult neuromuscular junctions.

Science.gov (United States)

Santafé, Manel M; Garcia, Neus; Tomàs, Marta; Obis, Teresa; Lanuza, Maria A; Besalduch, Nuria; Tomàs, Josep

2014-02-21

We conducted an electrophysiological study of the functional link between the tropomyosin-related kinase B (trkB) receptor signaling mechanism and serine-threonine kinases, both protein kinase C (PKC) and protein kinase A (PKA). We describe their coordinated role in transmitter release at the neuromuscular junction (NMJ) of the Levator auris longus muscle of the adult mouse. The trkB receptor normally seems to be coupled to stimulate ACh release because inhibiting the trkB receptor with K-252a results in a significant reduction in the size of EPPs. We found that the intracellular PKC pathway can operate as in basal conditions (to potentiate ACh release) without the involvement of the trkB receptor function, although the trkB pathway needs an operative PKC pathway if it is to couple to the release mechanism and potentiate it. To actively stimulate PKA (which also results in ACh release potentiation), the operativity of trkB is a necessary condition, and one effect of trkB may be PKA stimulation. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Estimate of the absorbed dose in the mouse organs and tissues after tritium administration

International Nuclear Information System (INIS)

Saito, Masahiro

2000-01-01

Chronic and accidental release of tritium from future fusion facilities may cause some extent of hazardous effect to the public health. Various experiments using small animals such as mice have been performed to mimic the dose accumulation due to tritium intake by the human body. An difficulty in such animal experiments using small animals is that it is rather difficult to administer tritium orally and estimate the dose to small organs or tissues. In the course of our study, a simple method to administer THO and T-labeled amino acids orally to the mouse was dictated and dose accumulation in various organs and tissues was determined. The tritium retention in the bone marrow was also determined using the micro-centrifuge method. Throughout our experiment, colony-bred DDY mice were used. The 8-10 week old male mice were orally and intraperitoneally administered THO water or T-amino acids mixture solution. For the purpose of oral administration, a 10 μl aliquot of T-containing saline solution was placed on the tongue of the mice using an automatic micropipette. At various times after tritium administration, the animals were sacrificed and the amount of tritium in various tissues and organs including bone marrow was examined. Dose accumulation pattern after THO intake and T-amino acids was compared between intraperitoneal injection and oral administration. The accumulated dose after oral administration of THO exhibited a tendency to be 10-20% higher than after intraperitoneal injection. The bone marrow dose after oral intake of THO was found to be lower than the doses to urine, blood, liver and testis. In contrast, the blood dose gave a conservative estimate for the dose to the other tissues and organs. (author)

Ornithine decarboxylase activity in rat organs and tissues under artificial hypobiosis.

Science.gov (United States)

Aksyonova, G E; Logvinovich, O S; Fialkovskaya, L A; Afanasyev, V N; Ignat'ev, D A; Kolomiytseva, I K

2010-09-01

The influence of hypothermia-hypoxia-hypercapnia on ornithine decarboxylase (ODC, EC 4.1.1.17) activities in rat organs and tissues and also on the thymocyte distribution throughout the cell cycle stages was studied. The state of artificial hypobiosis in rats on decrease in the body temperature to 14.4-18.0°C during 3.0-3.5 h was accompanied by drops in the ODC activities in the neocortex and liver by 50-60% and in rapidly proliferating tissues (thymus, spleen, and small intestine mucosa) by 80% of the control value. In kidneys the ODC activity raised to 200% of the control level. Twenty-four hours after termination of the cooling and replacing the rats under the standard conditions, the ODC activities in the neocortex, liver, kidneys, spleen, and intestinal mucosa returned to the control values, but remained decreased in the thymus. Forty-eight hours later the ODC activities in the thymus and spleen exceeded the normal level. The distribution of thymocytes throughout the cell cycle stages did not change in rats in the state of hypothermia (hypobiosis); 24 and 48 h after termination of the cooling the fraction of thymocytes in the S stage was decreased and the fraction of the cells in the G(0)+G(1) stage was increased. The normal distribution of thymocytes throughout the cell cycle stages recovered in 72 h. Thus, in the thymus the diminution of the ODC activity preceded the suppression of the cell proliferation rate. The tissue-specific changes in the ODC activity are suggested to reflect adaptive changes in the functional and proliferative activities of organs and tissues during the development of hypobiosis under conditions of hypothermia-hypoxia-hypercapnia.

The rapid manufacture of uniform composite multicellular-biomaterial micropellets, their assembly into macroscopic organized tissues, and potential applications in cartilage tissue engineering.

Directory of Open Access Journals (Sweden)

Betul Kul Babur

Full Text Available We and others have published on the rapid manufacture of micropellet tissues, typically formed from 100-500 cells each. The micropellet geometry enhances cellular biological properties, and in many cases the micropellets can subsequently be utilized as building blocks to assemble complex macrotissues. Generally, micropellets are formed from cells alone, however when replicating matrix-rich tissues such as cartilage it would be ideal if matrix or biomaterials supplements could be incorporated directly into the micropellet during the manufacturing process. Herein we describe a method to efficiently incorporate donor cartilage matrix into tissue engineered cartilage micropellets. We lyophilized bovine cartilage matrix, and then shattered it into microscopic pieces having average dimensions < 10 μm diameter; we termed this microscopic donor matrix "cartilage dust (CD". Using a microwell platform, we show that ~0.83 μg CD can be rapidly and efficiently incorporated into single multicellular aggregates formed from 180 bone marrow mesenchymal stem/stromal cells (MSC each. The microwell platform enabled the rapid manufacture of thousands of replica composite micropellets, with each micropellet having a material/CD core and a cellular surface. This micropellet organization enabled the rapid bulking up of the micropellet core matrix content, and left an adhesive cellular outer surface. This morphological organization enabled the ready assembly of the composite micropellets into macroscopic tissues. Generically, this is a versatile method that enables the rapid and uniform integration of biomaterials into multicellular micropellets that can then be used as tissue building blocks. In this study, the addition of CD resulted in an approximate 8-fold volume increase in the micropellets, with the donor matrix functioning to contribute to an increase in total cartilage matrix content. Composite micropellets were readily assembled into macroscopic cartilage

Associations of persistent organic pollutants in serum and adipose tissue with breast cancer prognostic markers

Energy Technology Data Exchange (ETDEWEB)

Arrebola, J.P., E-mail: jparrebola@ugr.es [Instituto de Investigación Biosanitaria (ibs. GRANADA), Hospitales Universitarios de Granada (Spain); Virgen de las Nieves University Hospital, Radiation Oncology Department, Oncology Unit, Granada (Spain); CIBER en Epidemiología y Salud Pública (CIBERESP) (Spain); Fernández-Rodríguez, M.; Artacho-Cordón, F. [Instituto de Investigación Biosanitaria (ibs. GRANADA), Hospitales Universitarios de Granada (Spain); University of Granada, Radiology and Physical Medicine Department (Spain); Garde, C. [Instituto de Investigación Biosanitaria (ibs. GRANADA), Hospitales Universitarios de Granada (Spain); Perez-Carrascosa, F.; Linares, I.; Tovar, I. [Instituto de Investigación Biosanitaria (ibs. GRANADA), Hospitales Universitarios de Granada (Spain); Virgen de las Nieves University Hospital, Radiation Oncology Department, Oncology Unit, Granada (Spain); González-Alzaga, B. [Instituto de Investigación Biosanitaria (ibs. GRANADA), Hospitales Universitarios de Granada (Spain); Escuela Andaluza de Salud Pública, Granada (Spain); Expósito, J. [Instituto de Investigación Biosanitaria (ibs. GRANADA), Hospitales Universitarios de Granada (Spain); Virgen de las Nieves University Hospital, Radiation Oncology Department, Oncology Unit, Granada (Spain); Torne, P. [Instituto de Investigación Biosanitaria (ibs. GRANADA), Hospitales Universitarios de Granada (Spain); and others

2016-10-01

This study aimed to evaluate associations between exposure to a group of persistent organic pollutants, measured in both adipose tissue and serum samples from breast cancer patients, and a set of tumor prognostic markers. The study population comprised 103 breast cancer patients recruited in Granada, Southern Spain. Data for tumor prognostic markers were retrieved from hospital clinical records and socio-demographic information was gathered by questionnaire. Persistent organic pollutants were quantified by gas chromatography with electron capture detection. Exposure levels were categorized in quartiles, and associations were evaluated using unconditional logistic regression. Adipose tissue HCB concentrations were associated positively with ER and PR expression (p-trends = 0.044 and 0.005, respectively) and negatively with E-Cadherin and p53 expression (p-trends = 0.012 and 0.027, respectively). PCB-180 adipose tissue concentrations were positively associated with HER2 expression (p-trend = 0.036). Serum PCB-138 concentrations were positively associated with ER and PR expression (p-trends = 0.052 and 0.042, respectively). The risk of p53 expression was higher among women in the lowest quartile of serum PCB-138 concentrations, but no significant trend was observed (p-trend = 0.161). These findings indicate that human exposure to certain persistent organic pollutants might be related to breast cancer aggressiveness. We also highlight the influence on exposure assessment of the biological matrix selected, given that both serum and adipose tissue might yield relevant information on breast cancer prognosis. - Highlights: • The role of POP exposure on the pathogenesis breast cancer is still controversial. • POPs were analyzed in serum and adipose tissue from breast cancer patients. • POP concentrations were associated with breast cancer prognostic markers. • POPs in serum and adipose tissue of breast cancer patients may provide different clues.

Associations of persistent organic pollutants in serum and adipose tissue with breast cancer prognostic markers

International Nuclear Information System (INIS)

Arrebola, J.P.; Fernández-Rodríguez, M.; Artacho-Cordón, F.; Garde, C.; Perez-Carrascosa, F.; Linares, I.; Tovar, I.; González-Alzaga, B.; Expósito, J.; Torne, P.

2016-01-01

This study aimed to evaluate associations between exposure to a group of persistent organic pollutants, measured in both adipose tissue and serum samples from breast cancer patients, and a set of tumor prognostic markers. The study population comprised 103 breast cancer patients recruited in Granada, Southern Spain. Data for tumor prognostic markers were retrieved from hospital clinical records and socio-demographic information was gathered by questionnaire. Persistent organic pollutants were quantified by gas chromatography with electron capture detection. Exposure levels were categorized in quartiles, and associations were evaluated using unconditional logistic regression. Adipose tissue HCB concentrations were associated positively with ER and PR expression (p-trends = 0.044 and 0.005, respectively) and negatively with E-Cadherin and p53 expression (p-trends = 0.012 and 0.027, respectively). PCB-180 adipose tissue concentrations were positively associated with HER2 expression (p-trend = 0.036). Serum PCB-138 concentrations were positively associated with ER and PR expression (p-trends = 0.052 and 0.042, respectively). The risk of p53 expression was higher among women in the lowest quartile of serum PCB-138 concentrations, but no significant trend was observed (p-trend = 0.161). These findings indicate that human exposure to certain persistent organic pollutants might be related to breast cancer aggressiveness. We also highlight the influence on exposure assessment of the biological matrix selected, given that both serum and adipose tissue might yield relevant information on breast cancer prognosis. - Highlights: • The role of POP exposure on the pathogenesis breast cancer is still controversial. • POPs were analyzed in serum and adipose tissue from breast cancer patients. • POP concentrations were associated with breast cancer prognostic markers. • POPs in serum and adipose tissue of breast cancer patients may provide different clues.

Certification of methylmercury content in two fresh-frozen reference materials: SRM 1947 Lake Michigan fish tissue and SRM 1974b organics in mussel tissue (Mytilus edulis)

International Nuclear Information System (INIS)

Davis, W.C.; Christopher, S.J.; Pugh, Rebecca S.; Donard, O.F.X.; Krupp, Eva A.; Point, David; Horvat, Milena; Gibicar, D.; Kljakovic-Gaspic, Z.; Porter, Barbara J.; Schantz, Michele M.

2007-01-01

This paper describes the development of two independent analytical methods for the extraction and quantification of methylmercury from marine biota. The procedures involve microwave extraction, followed by derivatization and either headspace solid-phase microextraction (SPME) with a polydimethylsiloxane (PDMS)-coated silica fiber or back-extraction into iso-octane. The identification and quantification of the extracted compounds is carried out by capillary gas chromatography/mass spectrometric (GC/MS) and inductively coupled plasma mass spectrometric (GC/ICP-MS) detection. Both methods were validated for the determination of methylmercury (MeHg) concentrations in a variety of biological standard reference materials (SRMs) including fresh-frozen tissue homogenates of SRM 1946 Lake Superior fish tissue and SRM 1974a organics in mussel tissue (Mytilus edulis) and then applied to the certification effort of SRM 1947 Lake Michigan fish tissue and SRM 1974b organics in mussel tissue (Mytilus edulis). While past certifications of methylmercury in tissue SRMs have been based on two independent methods from the National Institute of Standards and Technology (NIST) and participating laboratories, the methods described within provide improved protocols and will allow future certification efforts to be based on at least two independent analytical methods within NIST. (orig.)

Certification of methylmercury content in two fresh-frozen reference materials: SRM 1947 Lake Michigan fish tissue and SRM 1974b organics in mussel tissue (Mytilus edulis)

Energy Technology Data Exchange (ETDEWEB)

Davis, W.C.; Christopher, S.J.; Pugh, Rebecca S. [National Institute of Standards and Technology (NIST), Hollings Marine Laboratory, Analytical Chemistry Division, Charleston, SC (United States); Donard, O.F.X.; Krupp, Eva A. [LCABIE/CNRS Helioparc Pau-Pyrenees, Pau (France); Point, David [National Institute of Standards and Technology (NIST), Hollings Marine Laboratory, Analytical Chemistry Division, Charleston, SC (United States); LCABIE/CNRS Helioparc Pau-Pyrenees, Pau (France); Horvat, Milena; Gibicar, D. [Jozef Stefan Institute, Ljubljana (Slovenia); Kljakovic-Gaspic, Z. [Jozef Stefan Institute, Ljubljana (Slovenia); Institute for Medical Research and Occupational Health, Zagreb (Croatia); Porter, Barbara J.; Schantz, Michele M. [National Institute of Standards and Technology (NIST), Analytical Chemistry Division, Gaithersburg, MD (United States)

2007-04-15

This paper describes the development of two independent analytical methods for the extraction and quantification of methylmercury from marine biota. The procedures involve microwave extraction, followed by derivatization and either headspace solid-phase microextraction (SPME) with a polydimethylsiloxane (PDMS)-coated silica fiber or back-extraction into iso-octane. The identification and quantification of the extracted compounds is carried out by capillary gas chromatography/mass spectrometric (GC/MS) and inductively coupled plasma mass spectrometric (GC/ICP-MS) detection. Both methods were validated for the determination of methylmercury (MeHg) concentrations in a variety of biological standard reference materials (SRMs) including fresh-frozen tissue homogenates of SRM 1946 Lake Superior fish tissue and SRM 1974a organics in mussel tissue (Mytilus edulis) and then applied to the certification effort of SRM 1947 Lake Michigan fish tissue and SRM 1974b organics in mussel tissue (Mytilus edulis). While past certifications of methylmercury in tissue SRMs have been based on two independent methods from the National Institute of Standards and Technology (NIST) and participating laboratories, the methods described within provide improved protocols and will allow future certification efforts to be based on at least two independent analytical methods within NIST. (orig.)

Mesenchymal Stem Cells From Bone Marrow, Adipose Tissue, and Lung Tissue Differentially Mitigate Lung and Distal Organ Damage in Experimental Acute Respiratory Distress Syndrome.

Science.gov (United States)

Silva, Johnatas D; Lopes-Pacheco, Miquéias; Paz, Ana H R; Cruz, Fernanda F; Melo, Elga B; de Oliveira, Milena V; Xisto, Débora G; Capelozzi, Vera L; Morales, Marcelo M; Pelosi, Paolo; Cirne-Lima, Elizabeth; Rocco, Patricia R M

2018-02-01

Mesenchymal stem cells-based therapies have shown promising effects in experimental acute respiratory distress syndrome. Different mesenchymal stem cells sources may result in diverse effects in respiratory diseases; however, there is no information regarding the best source of mesenchymal stem cells to treat pulmonary acute respiratory distress syndrome. We tested the hypothesis that mesenchymal stem cells derived from bone marrow, adipose tissue, and lung tissue would lead to different beneficial effects on lung and distal organ damage in experimental pulmonary acute respiratory distress syndrome. Animal study and primary cell culture. Laboratory investigation. Seventy-five Wistar rats. Wistar rats received saline (control) or Escherichia coli lipopolysaccharide (acute respiratory distress syndrome) intratracheally. On day 2, acute respiratory distress syndrome animals were further randomized to receive saline or bone marrow, adipose tissue, or lung tissue mesenchymal stem cells (1 × 10 cells) IV. Lung mechanics, histology, and protein levels of inflammatory mediators and growth factors were analyzed 5 days after mesenchymal stem cells administration. RAW 264.7 cells (a macrophage cell line) were incubated with lipopolysaccharide followed by coculture or not with bone marrow, adipose tissue, and lung tissue mesenchymal stem cells (10 cells/mL medium). Regardless of mesenchymal stem cells source, cells administration improved lung function and reduced alveolar collapse, tissue cellularity, collagen, and elastic fiber content in lung tissue, as well as decreased apoptotic cell counts in liver. Bone marrow and adipose tissue mesenchymal stem cells administration also reduced levels of tumor necrosis factor-α, interleukin-1β, keratinocyte-derived chemokine, transforming growth factor-β, and vascular endothelial growth factor, as well as apoptotic cell counts in lung and kidney, while increasing expression of keratinocyte growth factor in lung tissue

Evidence of the Association Between Psychology and Tissue and Organ Transplantation in Brazil.

Science.gov (United States)

Silva, J D A; Ariente, L C; Roza, B A; Mucci, S

2016-09-01

The addition of psychologists to organ transplant teams is still new in Brazil. In seeking the efficient performance of this professional, the knowledge of the scientific production and the development of research in the area is fundamental. In this sense, this study aims to survey the Brazilian scientific research that has investigated the psychologic aspects involved in tissue and organ transplantation. A literature narrative review was performed with the use of the "Transplante AND Psicologia" descriptors in the Biblioteca Virtual em Saúde and the CAPES Journal Portal. Fifty-three articles were found, of which 22 met the inclusion criteria: publications dating from 2000 to 2014 and the main topic of interest of the studies being quality of life, followed by organ donation. The instruments used most frequently were interviews developed by the researchers and the SF-36 Quality of Life Questionnaire. Recent Brazilian studies on the association between psychology and transplantation are still scarce, possibly because of the recent addition of psychologists to transplantation teams. Therefore, it is suggested that more scientific research is made in the area and that the objects of study are more varied, to ensure adequacy of the psychologist to meet the specific demands of organ and tissue transplantation process. Copyright © 2016 Elsevier Inc. All rights reserved.

Geo-PET: A novel generic organ-pet for small animal organs and tissues

Science.gov (United States)

Sensoy, Levent

Reconstructed tomographic image resolution of small animal PET imaging systems is improving with advances in radiation detector development. However the trend towards higher resolution systems has come with an increase in price and system complexity. Recent developments in the area of solid-state photomultiplication devices like silicon photomultiplier arrays (SPMA) are creating opportunities for new high performance tools for PET scanner design. Imaging of excised small animal organs and tissues has been used as part of post-mortem studies in order to gain detailed, high-resolution anatomical information on sacrificed animals. However, this kind of ex-vivo specimen imaging has largely been limited to ultra-high resolution muCT. The inherent limitations to PET resolution have, to date, excluded PET imaging from these ex-vivo imaging studies. In this work, we leverage the diminishing physical size of current generation SPMA designs to create a very small, simple, and high-resolution prototype detector system targeting ex-vivo tomographic imaging of small animal organs and tissues. We investigate sensitivity, spatial resolution, and the reconstructed image quality of a prototype small animal PET scanner designed specifically for imaging of excised murine tissue and organs. We aim to demonstrate that a cost-effective silicon photomultiplier (SiPM) array based design with thin crystals (2 mm) to minimize depth of interaction errors might be able to achieve sub-millimeter resolution. We hypothesize that the substantial decrease in sensitivity associated with the thin crystals can be compensated for with increased solid angle detection, longer acquisitions, higher activity and wider acceptance energy windows (due to minimal scatter from excised organs). The constructed system has a functional field of view (FoV) of 40 mm diameter, which is adequate for most small animal specimen studies. We perform both analytical (3D-FBP) and iterative (ML-EM) methods in order to

Present dose limits and their relation to radiosensitivity of different organs and tissues

International Nuclear Information System (INIS)

Anon.

1987-01-01

Dose equivalent limits in relation to dose thresholds are considered for injury of various tissues and organs to evaluate the protection agains non-stochastic irradiation effects by the existing system of dose limitation for radiotherapeutic personnel. Data on tissue radiosensitivity in relation to non-stochastic effects, obtained from radiotherapeutic experience, are presented. Dose threshold values, derived for patients, with a correction in the direction of increase, may be applied to conditions of occupational exposure except for bone marrow, gonads and eye lens, where threshold doses are lower

FAMILY CONSENT FOR ORGAN OR TISSUE REMOVAL FROM A DECEASED PERSON FOR TRANSPLANTATION PURPOSES IN THE REPUBLIC OF CROATIA

Directory of Open Access Journals (Sweden)

Tomislav Nedić

2017-04-01

Full Text Available The Republic of Croatia is a country with the system of presumed consent donation of organs and tissues after death, where the consent of the family, according to law, is not one of the conditions for organ or tissue removal for transplantation purposes. However, the consent is a condition required by the Codex of Medical Ethics and Deontology. The author primary proposes harmonization of the Codex with current legislation. Accordingly, this paper primarily analyses the typology of the Codex, ethical issues and ethical and positivist reasons to harmonize the Codex with current legislation. Furthermore, although the author in the first place considers that the Codex should be in line with legislation, he also considers the provision of family consent for organ and tissue removal itself flawed and poorly developed. In this regard, the author considers the comparative legislation and judgments of the European Court of Human Rights, analyses current provisions of the Codex in the part of the removal and transplantation of organs and tissues from deceased persons, states the facts that the Codex should contain so as to make the mechanism of family consent for organ and tissue removal and donation after death more effective. In fact, if the author’s original proposal for harmonization of the Codex with the current legislation is not accepted, a more detailed and precise elaboration of the mentioned current provisions of the Codex will be suggested. This will include exact definition of the family and relatives, exact deadlines and ways of informing the family, but also refining the concept of “ethical“ according to the Codex in part of the organ and tissue donation and removal from the deceased person.

Macro-and micro-autoradiographic study in comparison with the incorporation of 35S-methionine by various tissue protein in organism

International Nuclear Information System (INIS)

Zhu Shoupeng; Mei Shengping; Le Shangcheng

1990-12-01

The purpose of the study was to observe the incorporation level of 35 S-methionine by various tissue protein in organism. By the use of the macro-and micro-autoradiographic technique, the incorporation of 35 S-methionine by the tissues has been utilized as an index of various tissue protein synthesis. On this basis, the further experiments showed that tracer agent 35 S-methionine was dominantly incorporated in the immature cells of bone marrow and the tissue of liver, kidney and spleen. Its incorporation increased gradually with time. From the experimental results it can be concluded that a strong protein biosynthesis metabolism was produced in these tissues. While the tissues have important physiological function in organism, such as heart, lung and skeletal muscle, but the protein biosynthesis in those tissues was at a low level

Improved application of the electrophoretic tissue clearing technology, CLARITY, to intact solid organs including brain, pancreas, liver, kidney, lung, and intestine.

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Lee, Hyunsu; Park, Jae-Hyung; Seo, Incheol; Park, Sun-Hyun; Kim, Shin

2014-12-21

Mapping of tissue structure at the cellular, circuit, and organ-wide scale is important for understanding physiological and biological functions. A bio-electrochemical technique known as CLARITY used for three-dimensional anatomical and phenotypical mapping within transparent intact tissues has been recently developed. This method provided a major advance in understanding the structure-function relationships in circuits of the nervous system and organs by using whole-body clearing. Thus, in the present study, we aimed to improve the original CLARITY procedure and developed specific CLARITY protocols for various intact organs. We determined the optimal conditions for reducing bubble formation, discoloration, and depositing of black particles on the surface of tissue, which allowed production of clearer organ images. We also determined the appropriate replacement cycles of clearing solution for each type of organ, and convincingly demonstrated that 250-280 mA is the ideal range of electrical current for tissue clearing. We then acquired each type of cleared organs including brain, pancreas, liver, lung, kidney, and intestine. Additionally, we determined the images of axon fibers of hippocampal region, the Purkinje layer of cerebellum, and vessels and cellular nuclei of pancreas. CLARITY is an innovative biochemical technology for the structural and molecular analysis of various types of tissue. We developed improved CLARITY methods for clearing of the brain, pancreas, lung, intestine, liver, and kidney, and identified the appropriate experimental conditions for clearing of each specific tissue type. These optimized methods will be useful for the application of CLARITY to various types of organs.

Organ and tissue donation: what do high school students know?

Directory of Open Access Journals (Sweden)

Marcela Cristina de Lemos

2007-09-01

Full Text Available Objectives: To know the opinion of senior high school students in publicand private schools on the process of donating and transplanting organsand tissues, and their desire to be donors. Methods: A descriptive crosssectionalstudy, conducted from 2004 to 2005, on the opinion/knowledgeof senior high school students in public and private schools in the VilaMariana region of the city of São Paulo, on the process of organ and tissuedonation and transplantation. The convenience sample was made up of140 (81% students from two private schools and 167 (51% studentsfrom a public school. The project was approved by the Research EthicsCommittee of the UNIFESP. Results: Data showed that 163 (53.1%students believe that donation is by presumed consent and 147 (47.9%that consider that it occurs by informed consent. Of the public schoolstudents, 120 (71.9% believe that transplants are public and free ofcharge in Brazil versus 94 (67.1% of the students from private schools.Students know that donations may be made by living or dead donors(121 - 86.4% private schools versus 113 – 67.7% public school. Wehighlight that 22 (15.7% of the private school students and 16 (9.6%of those from the public school believe that the commerce of organs isallowed in Brazil. As to intentions of being a donor, 108 (77.1% of theprivate school students declared themselves organ and tissue donorsversus 106 (63.5% from the public school, and 63 (59.4% from thepublic versus 61 (56.5% from the private schools have already informedtheir families. Conclusion: There was no difference in knowledge andopinion among the students from the public and private schools as toaspects regarding donation and transplantation.

Selection of reference genes for tissue/organ samples on day 3 fifth-instar larvae in silkworm, Bombyx mori.

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Wang, Genhong; Chen, Yanfei; Zhang, Xiaoying; Bai, Bingchuan; Yan, Hao; Qin, Daoyuan; Xia, Qingyou

2018-06-01

The silkworm, Bombyx mori, is one of the world's most economically important insect. Surveying variations in gene expression among multiple tissue/organ samples will provide clues for gene function assignments and will be helpful for identifying genes related to economic traits or specific cellular processes. To ensure their accuracy, commonly used gene expression quantification methods require a set of stable reference genes for data normalization. In this study, 24 candidate reference genes were assessed in 10 tissue/organ samples of day 3 fifth-instar B. mori larvae using geNorm and NormFinder. The results revealed that, using the combination of the expression of BGIBMGA003186 and BGIBMGA008209 was the optimum choice for normalizing the expression data of the B. mori tissue/organ samples. The most stable gene, BGIBMGA003186, is recommended if just one reference gene is used. Moreover, the commonly used reference gene encoding cytoplasmic actin was the least appropriate reference gene of the samples investigated. The reliability of the selected reference genes was further confirmed by evaluating the expression profiles of two cathepsin genes. Our results may be useful for future studies involving the quantification of relative gene expression levels of different tissue/organ samples in B. mori. © 2018 Wiley Periodicals, Inc.

Determining the effect of malondialdehyde on the IgE-binding capacity of shrimp tropomyosin upon in vitro digestion.

Science.gov (United States)

Lv, Liangtao; Lin, Hong; Li, Zhenxing; Ahmed, Ishfaq; Chen, Guanzhi

2017-10-01

Stability in simulated gastric fluids is considered an important parameter for the estimation of food allergenicity. Moreover, proteins in food are highly susceptible to lipid oxidation during processing and preservation. In this study, the change in the IgE-binding capacity of malondialdehyde (MDA)-treated shrimp tropomyosin (TM) following in vitro digestion was investigated by SDS-PAGE and western blot. Shrimp TM treated with different concentrations of MDA was slightly degraded and became increasingly resistant to pepsin digestion over time. While untreated TM was rapidly degraded, MDA-treated TM showed some resistance and was degraded by trypsin only after increasing the digestion time. Results of immunoblotting studies on IgE using sera from patients allergic to shrimp indicated that the IgE-binding capacity of TM and MDA (50 mmol L -1 )-treated TM decreased slightly after pepsin digestion and significantly decreased after trypsin digestion. The study indicated that the resistance of TM to degradation increased after oxidation. The treatment with proteases, especially trypsin, is quite effective in decreasing the IgG/IgE-binding capacity of shrimp TM. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Multi-target determination of organic ultraviolet absorbents in organism tissues by ultrasonic assisted extraction and ultra-high performance liquid chromatography-tandem mass spectrometry.

Science.gov (United States)

Peng, Xianzhi; Jin, Jiabin; Wang, Chunwei; Ou, Weihui; Tang, Caiming

2015-03-06

A sensitive and reliable method was developed for multi-target determination of 13 most widely used organic ultraviolet (UV) absorbents (including UV filters and UV stabilizers) in aquatic organism tissues. The organic UV absorbents were extracted using ultrasonic-assisted extraction, purified via gel permeation chromatography coupled with silica gel column chromatography, and determined by ultra-high performance liquid chromatography-tandem mass spectrometry. Recoveries of the UV absorbents from organism tissues mostly ranged from 70% to 120% from fish filet with satisfactory reproducibility. Method quantification limits were 0.003-1.0ngg(-1) dry weight (dw) except for 2-ethylhexyl 4-methoxycinnamate. This method has been applied to analysis of the UV absorbents in wild and farmed aquatic organisms collected from the Pearl River Estuary, South China. 2-Hydroxy-4-methoxybenzophenone and UV-P were frequently detected in both wild and farmed marine organisms at low ngg(-1)dw. 3-(4-Methylbenzylidene)camphor and most of the benzotriazole UV stabilizers were also frequently detected in maricultured fish. Octocrylene and 2-ethylhexyl 4-methoxycinnamate were not detected in any sample. This work lays basis for in-depth study about bioaccumulation and biomagnification of the UV absorbents in marine environment. Copyright © 2015 Elsevier B.V. All rights reserved.

Characterization of the mechanical properties of resected porcine organ tissue using optical fiber photoelastic polarimetry.

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Hudnut, Alexa W; Babaei, Behzad; Liu, Sonya; Larson, Brent K; Mumenthaler, Shannon M; Armani, Andrea M

2017-10-01

Characterizing the mechanical behavior of living tissue presents an interesting challenge because the elasticity varies by eight orders of magnitude, from 50Pa to 5GPa. In the present work, a non-destructive optical fiber photoelastic polarimetry system is used to analyze the mechanical properties of resected samples from porcine liver, kidney, and pancreas. Using a quasi-linear viscoelastic fit, the elastic modulus values of the different organ systems are determined. They are in agreement with previous work. In addition, a histological assessment of compressed and uncompressed tissues confirms that the tissue is not damaged during testing.

Enamel tissue engineering using subcultured enamel organ epithelial cells in combination with dental pulp cells.

Science.gov (United States)

Honda, Masaki J; Shinmura, Yuka; Shinohara, Yoshinori

2009-01-01

We describe a strategy for the in vitro engineering of enamel tissue using a novel technique for culturing enamel organ epithelial (EOE) cells isolated from the enamel organ using 3T3-J2 cells as a feeder layer. These subcultured EOE cells retain the capacity to produce enamel structures over a period of extended culture. In brief, enamel organs from 6-month-old porcine third molars were dissociated into single cells and subcultured on 3T3-J2 feeder cell layers. These subcultured EOE cells were then seeded onto a collagen sponge in combination with primary dental pulp cells isolated at an early stage of crown formation, and these constructs were transplanted into athymic rats. After 4 weeks, complex enamel-dentin structures were detected in the implants. These results show that our culture technique maintained ameloblast lineage cells that were able to produce enamel in vivo. This novel subculture technique provides an important tool for tooth tissue engineering. Copyright 2008 S. Karger AG, Basel.

Monte Carlo Method in the calculate of conversion coefficients for dose in children's organs and tissues subjected to dentistric radiography

International Nuclear Information System (INIS)

Loureiro, E.C.M.; Khoury, H.; Lima, F.R.A.

1998-01-01

The increasing utilization of oral X-rays, specially in youngsters and children, prompts the assessment of equivalent doses in their organs and tissues. With this purpose, Monte Carlo code was adopted to simulate an X-ray source irradiating phantoms of the MIRD-5 type with different ages (10, 15 and 40 years old) to calculate the conversion coefficients which transform the exposure at skin to equivalent doses at several organs and tissues of interest. In order to check the computer program, simulations were performed for adult patients using the original code (ADAM,FOR developed by GSF Germany) and the adapted program (MCDRO,PAS). Good agreement between results obtained by both programs was observed. Applications to incisive, canine and molar teeth were simulated. The conversion factors were calculated for the following organs and tissues: thyroid, active bone marrow (head and whole body), bone (facial skeleton, cranium and whole body), skin (head and whole body) and crystalline. Based on the obtained results, it follows that the younger the patient and the langer the field area, the higher the doses in assessed organs and tissues

Concentrations of transuranic elements in critical organs and tissues of goats (CAPRA HIRCUS)

International Nuclear Information System (INIS)

Averin, V.S.; Vaskovtsova, V.A.; Kuhtsevich, A.B.; Tagai, S.A.; Tsarenok, A.A.; Buzdalkin, K.N.; Gvozdik, A.F.; Makarovets, I.V.; Nilova, E.K.

2012-01-01

Parameters of Am 241 and Pu 238, 239+240 transfer from the dietary soil-based component (mineral soil) to organs and tissues of goats during a grazing period of 80 and 160 days have been determined. The maximum specific activities of transuranic elements have been found in liver of goats. (authors)

Quantitative 3D Analysis of Nuclear Morphology and Heterochromatin Organization from Whole-Mount Plant Tissue Using NucleusJ.

Science.gov (United States)

Desset, Sophie; Poulet, Axel; Tatout, Christophe

2018-01-01

Image analysis is a classical way to study nuclear organization. While nuclear organization used to be investigated by colorimetric or fluorescent labeling of DNA or specific nuclear compartments, new methods in microscopy imaging now enable qualitative and quantitative analyses of chromatin pattern, and nuclear size and shape. Several procedures have been developed to prepare samples in order to collect 3D images for the analysis of spatial chromatin organization, but only few preserve the positional information of the cell within its tissue context. Here, we describe a whole mount tissue preparation procedure coupled to DNA staining using the PicoGreen ® intercalating agent suitable for image analysis of the nucleus in living and fixed tissues. 3D Image analysis is then performed using NucleusJ, an open source ImageJ plugin, which allows for quantifying variations in nuclear morphology such as nuclear volume, sphericity, elongation, and flatness as well as in heterochromatin content and position in respect to the nuclear periphery.

Am80 induces neuronal differentiation via increased tropomyosin-related kinase B expression in a human neuroblastoma SH-SY5Y cell line.

Science.gov (United States)

Shiohira, Hideo; Kitaoka, Akira; Enjoji, Munechika; Uno, Tsukasa; Nakashima, Manabu

2012-01-01

Am80, a synthetic retinoid, has been used in differentiation therapy for acute promyelocytic leukemia (APL). All-trans retinoic acid (ATRA) as one of natural retinoid has been also used to treat APL. ATRA treatment causes neuronal differentiation by inducing tropomyosin-related kinase B (TrkB) expression and increasing the sensitivity to brain-derived neurotrophic factor (BDNF), a TrkB ligand. In the present study, we investigated the effects of Am80 on neuronal differentiation, BDNF sensitivity and TrkB expression in human neuroblastoma SH-SY5Y cells. Treatment with Am80 induced morphological differentiation of neurite outgrowth and increased the expression of GAP43 mRNA, a neuronal differentiation marker. Additionally, TrkB protein was also increased, and exogenous BDNF stimulation after treatment with Am80 induced greater neurite outgrowth than without BDNF treatment. These results suggest that Am80 induced neuronal differentiation by increasing TrkB expression and BDNF sensitivity.

Bioprinting of a mechanically enhanced three-dimensional dual cell-laden construct for osteochondral tissue engineering using a multi-head tissue/organ building system

International Nuclear Information System (INIS)

Shim, Jin-Hyung; Lee, Jung-Seob; Cho, Dong-Woo; Kim, Jong Young

2012-01-01

The aim of this study was to build a mechanically enhanced three-dimensional (3D) bioprinted construct containing two different cell types for osteochondral tissue regeneration. Recently, the production of 3D cell-laden structures using various scaffold-free cell printing technologies has opened up new possibilities. However, ideal 3D complex tissues or organs have not yet been printed because gel-state hydrogels have been used as the principal material and are unable to maintain the desired 3D structure due to their poor mechanical strength. In this study, thermoplastic biomaterial polycaprolactone (PCL), which shows relatively high mechanical properties as compared with hydrogel, was used as a framework for enhancing the mechanical stability of the bioprinted construct. Two different alginate solutions were then infused into the previously prepared framework consisting of PCL to create the 3D construct for osteochondral printing. For this work, a multi-head tissue/organ building system (MtoBS), which was particularly designed to dispense thermoplastic biomaterial and hydrogel having completely different rheology properties, was newly developed and used to bioprint osteochondral tissue. It was confirmed that the line width, position and volume control of PCL and alginate solutions were adjustable in the MtoBS. Most importantly, dual cell-laden 3D constructs consisting of osteoblasts and chondrocytes were successfully fabricated. Further, the separately dispensed osteoblasts and chondrocytes not only retained their initial position and viability, but also proliferated up to 7 days after being dispensed. (paper)

Bioprinting of a mechanically enhanced three-dimensional dual cell-laden construct for osteochondral tissue engineering using a multi-head tissue/organ building system

Science.gov (United States)

Shim, Jin-Hyung; Lee, Jung-Seob; Kim, Jong Young; Cho, Dong-Woo

2012-08-01

The aim of this study was to build a mechanically enhanced three-dimensional (3D) bioprinted construct containing two different cell types for osteochondral tissue regeneration. Recently, the production of 3D cell-laden structures using various scaffold-free cell printing technologies has opened up new possibilities. However, ideal 3D complex tissues or organs have not yet been printed because gel-state hydrogels have been used as the principal material and are unable to maintain the desired 3D structure due to their poor mechanical strength. In this study, thermoplastic biomaterial polycaprolactone (PCL), which shows relatively high mechanical properties as compared with hydrogel, was used as a framework for enhancing the mechanical stability of the bioprinted construct. Two different alginate solutions were then infused into the previously prepared framework consisting of PCL to create the 3D construct for osteochondral printing. For this work, a multi-head tissue/organ building system (MtoBS), which was particularly designed to dispense thermoplastic biomaterial and hydrogel having completely different rheology properties, was newly developed and used to bioprint osteochondral tissue. It was confirmed that the line width, position and volume control of PCL and alginate solutions were adjustable in the MtoBS. Most importantly, dual cell-laden 3D constructs consisting of osteoblasts and chondrocytes were successfully fabricated. Further, the separately dispensed osteoblasts and chondrocytes not only retained their initial position and viability, but also proliferated up to 7 days after being dispensed.

Recent Advances in Understanding Pelvic-Floor Tissue of Women With and Without Pelvic Organ Prolapse: Considerations for Physical Therapists.

Science.gov (United States)

Saunders, Kimberly

2017-04-01

Pelvic organ prolapse is a fairly common condition that imposes significant symptoms, diminished quality of life, social burden, financial expense, and surgical risk on women. As evidence supporting the benefit of pelvic-floor muscle training in nonsurgical management of pelvic organ prolapse grows, physical therapists are becoming a provider of choice interacting with women affected by pelvic organ prolapse. This perspective article will review recent research on tissue characteristics of 3 key components of pelvic organ support: skeletal muscle, ligament, and vaginal wall. This information will be summarized as implications for physical therapists. An improved understanding of pelvic-floor tissue in women with and without pelvic organ prolapse will provide a more comprehensive appreciation of the interaction of multiple systems in the disorder. © 2017 American Physical Therapy Association.

The Grand Challenges of Organ Banking: Proceedings from the first global summit on complex tissue cryopreservation.

Science.gov (United States)

Lewis, Jedediah K; Bischof, John C; Braslavsky, Ido; Brockbank, Kelvin G M; Fahy, Gregory M; Fuller, Barry J; Rabin, Yoed; Tocchio, Alessandro; Woods, Erik J; Wowk, Brian G; Acker, Jason P; Giwa, Sebastian

2016-04-01

The first Organ Banking Summit was convened from Feb. 27 - March 1, 2015 in Palo Alto, CA, with events at Stanford University, NASA Research Park, and Lawrence Berkeley National Labs. Experts at the summit outlined the potential public health impact of organ banking, discussed the major remaining scientific challenges that need to be overcome in order to bank organs, and identified key opportunities to accelerate progress toward this goal. Many areas of public health could be revolutionized by the banking of organs and other complex tissues, including transplantation, oncofertility, tissue engineering, trauma medicine and emergency preparedness, basic biomedical research and drug discovery - and even space travel. Key remaining scientific sub-challenges were discussed including ice nucleation and growth, cryoprotectant and osmotic toxicities, chilling injury, thermo-mechanical stress, the need for rapid and uniform rewarming, and ischemia/reperfusion injury. A variety of opportunities to overcome these challenge areas were discussed, i.e. preconditioning for enhanced stress tolerance, nanoparticle rewarming, cyroprotectant screening strategies, and the use of cryoprotectant cocktails including ice binding agents. Copyright © 2015.

Tropomyosin Promotes Lamellipodial Persistence by Collaborating with Arp2/3 at the Leading Edge.

Science.gov (United States)

Brayford, Simon; Bryce, Nicole S; Schevzov, Galina; Haynes, Elizabeth M; Bear, James E; Hardeman, Edna C; Gunning, Peter W

2016-05-23

At the leading edge of migrating cells, protrusion of the lamellipodium is driven by Arp2/3-mediated polymerization of actin filaments [1]. This dense, branched actin network is promoted and stabilized by cortactin [2, 3]. In order to drive filament turnover, Arp2/3 networks are remodeled by proteins such as GMF, which blocks the actin-Arp2/3 interaction [4, 5], and coronin 1B, which acts by directing SSH1L to the lamellipodium where it activates the actin-severing protein cofilin [6, 7]. It has been shown in vitro that cofilin-mediated severing of Arp2/3 actin networks results in the generation of new pointed ends to which the actin-stabilizing protein tropomyosin (Tpm) can bind [8]. The presence of Tpm in lamellipodia, however, is disputed in the literature [9-19]. Here, we report that the Tpm isoforms 1.8/9 are enriched in the lamellipodium of fibroblasts as detected with a novel isoform-specific monoclonal antibody. RNAi-mediated silencing of Tpm1.8/9 led to an increase of Arp2/3 accumulation at the cell periphery and a decrease in the persistence of lamellipodia and cell motility, a phenotype consistent with cortactin- and coronin 1B-deficient cells [2, 7]. In the absence of coronin 1B or cofilin, Tpm1.8/9 protein levels are reduced while, conversely, inhibition of Arp2/3 with CK666 leads to an increase in Tpm1.8/9 protein. These findings establish a novel regulatory mechanism within the lamellipodium whereby Tpm collaborates with Arp2/3 to promote lamellipodial-based cell migration. Copyright © 2016 Elsevier Ltd. All rights reserved.

Carvedilol induces endogenous hydrogen sulfide tissue concentration changes in various mouse organs.

Science.gov (United States)

Wiliński, Bogdan; Wiliński, Jerzy; Somogyi, Eugeniusz; Piotrowska, Joanna; Góralska, Marta; Macura, Barbara

2011-01-01

Carvedilol, a third generation non-selective adrenoreceptor blocker, is widely used in cardiology. Its action has been proven to reach beyond adrenergic antagonism and involves multiple biological mechanisms. The interaction between carvedilol and endogenous 'gasotransmitter' hydrogen sulfide (H2S) is unknown. The aim of the study is to assess the influence of carvedilol on the H2S tissue level in mouse brain, liver, heart and kidney. Twenty eight SJL strain female mice were administered intraperitoneal injections of 2.5 mg/kg b.w./d (group D1, n=7), 5 mg/kg b.w./d (group D2, n=7) or 10 mg/kg b.w./d of carvedilol (group D3, n=7). The control group (n=7) received physiological saline in portions of the same volume (0.2 ml). Measurements of the free tissue H2S concentrations were performed according to the modified method of Siegel. A progressive decline in H2S tissue concentration along with an increase in carvedilol dose was observed in the brain (12.5%, 13.7% and 19.6%, respectively). Only the highest carvedilol dose induced a change in H2S tissue level in the heart - an increase by 75.5%. In the liver medium and high doses of carvedilol increased the H2S level by 48.1% and 11.8%, respectively. In the kidney, group D2 showed a significant decrease of H2S tissue level (22.5%), while in the D3 group the H2S concentration increased by 12.9%. Our study has proven that carvedilol affects H2S tissue concentration in different mouse organs.

Tropomyosin 4 defines novel filaments in skeletal muscle associated with muscle remodelling/regeneration in normal and diseased muscle.

Science.gov (United States)

Vlahovich, Nicole; Schevzov, Galina; Nair-Shaliker, Visalini; Ilkovski, Biljana; Artap, Stanley T; Joya, Josephine E; Kee, Anthony J; North, Kathryn N; Gunning, Peter W; Hardeman, Edna C

2008-01-01

The organisation of structural proteins in muscle into highly ordered sarcomeres occurs during development, regeneration and focal repair of skeletal muscle fibers. The involvement of cytoskeletal proteins in this process has been documented, with nonmuscle gamma-actin found to play a role in sarcomere assembly during muscle differentiation and also shown to be up-regulated in dystrophic muscles which undergo regeneration and repair [Lloyd et al.,2004; Hanft et al.,2006]. Here, we show that a cytoskeletal tropomyosin (Tm), Tm4, defines actin filaments in two novel compartments in muscle fibers: a Z-line associated cytoskeleton (Z-LAC), similar to a structure we have reported previously [Kee et al.,2004], and longitudinal filaments that are orientated parallel to the sarcomeric apparatus, present during myofiber growth and repair/regeneration. Tm4 is upregulated in paradigms of muscle repair including induced regeneration and focal repair and in muscle diseases with repair/regeneration features, muscular dystrophy and nemaline myopathy. Longitudinal Tm4-defined filaments also are present in diseased muscle. Transition of the Tm4-defined filaments from a longitudinal to a Z-LAC orientation is observed during the course of muscle regeneration. This Tm4-defined cytoskeleton is a marker of growth and repair/regeneration in response to injury, disease state and stress in skeletal muscle.

Results from the organ and tissue transplant program in Nuevo Leon, Mexico, 1996 to 2001.

Science.gov (United States)

Carbajal, H; Cabriales, H

2003-12-01

Before 1996, solid organs from cadaveric donors (CD) did not account for more than 2% of all transplants. The need for more transplants led the state to undergo several legislative, societal, organizational, and infrastructure changes. A descriptive analysis of the evolution of the transplant program in the State of Nuevo León, Mexico, from 1996 to 2001. Trimester reports have been routinely performed since 1996 from the 14 institutions that are licensed to perform organ and tissue transplants in the State of Nuevo León, Mexico. All reports were concentrated and a descriptive analysis is presented herein. From 1996 until 2001, a total of 1457 organ and tissue (OT) transplants have been performed. At the end of this period, there was a 214% increase in the total number of transplants. By 2001, 73% of the program's total of 1457 OT transplants came from cadaveric donors. The state transplant program of Nuevo León has experienced a dramatic growth since 1996. The percent of organs transplanted from cadaveric donors is one of the highest in Mexico. There is still much work to be done at the state and national levels; better epidemiological studies and dialysis registries are needed as well as investment in transplant research.

From Prevention To Advance In Biomedicine: The Transfer Of Organs And Tissues

Directory of Open Access Journals (Sweden)

Gemma Flores-Pons

2013-07-01

Full Text Available Currently, within Western societies, we can see new practices that are at once reality and fiction as they unfold in the terrain of the possible, the imaginable and the optimum. In the present paper, we focus on the case of organ and tissues transfer to describe how those biomedical actants and practices involved are articulated, configuring it as an anticipatory process, namely as a constant movement attempting to bring mobile futures to the present. Drawing on an ethnographic study exploring the everyday activity of a Spanish transplant coordination team,, we begin by suggesting that donation gets inserted as an imperative in the increasingly individualized management of the citizens’ biological becomings. Secondly, we turn to how the articulation of the brain death diagnosis functions as an entity capable of creating coherence between the different temporalities produced in the organs and tissues transfer. Then, we show the optimization mechanisms that operate within the waiting lists materializing imagined futures. Finally, by way of describing the permanent latency in which the transplant coordination teams work, we give an account of how biomedicine is turning away from generating practices inserted in a logic of prevention to practices that obey a logic of preparation.

Soft tissue organ masses of Beagles as a function of age

International Nuclear Information System (INIS)

Guilmette, R.A.; Gillett, N.A.; Gerlach, R.F.

1988-01-01

Beagle dogs have been used for the past 30 yr for radio toxicological studies in several Department of Energy laboratories. Since the animals are maintained for their life span, it is important to recognize the potential importance of age-related changes in organ masses, particularly as they relate to dosimetry. To determine the extent and magnitude of soft-tissue organ mass changes relative to age and gender of Beagle dogs, groups of three male and three female dogs at ages 2.7, 6.0, 8.8, 11.7, and 14.0 yr were sacrificed. The resulting organ mass data were analyzed by linear regression both in terms of gross mass and mass normalized to whole-body mass. The results indicated that very little change in masses could be detected in this population over the age range studied, which includes the median life span of dogs In this colony. The rate of change of masses was shown to have an insignificant effect on the calculation of radiation dose, even over long time periods. (author)

Soft tissue organ masses of Beagles as a function of age

Energy Technology Data Exchange (ETDEWEB)

Guilmette, R A; Gillett, N A; Gerlach, R F

1988-12-01

Beagle dogs have been used for the past 30 yr for radio toxicological studies in several Department of Energy laboratories. Since the animals are maintained for their life span, it is important to recognize the potential importance of age-related changes in organ masses, particularly as they relate to dosimetry. To determine the extent and magnitude of soft-tissue organ mass changes relative to age and gender of Beagle dogs, groups of three male and three female dogs at ages 2.7, 6.0, 8.8, 11.7, and 14.0 yr were sacrificed. The resulting organ mass data were analyzed by linear regression both in terms of gross mass and mass normalized to whole-body mass. The results indicated that very little change in masses could be detected in this population over the age range studied, which includes the median life span of dogs In this colony. The rate of change of masses was shown to have an insignificant effect on the calculation of radiation dose, even over long time periods. (author)

"Project ACTS": An Intervention to Increase Organ and Tissue Donation Intentions among African Americans

Science.gov (United States)

Arriola, Kimberly; Robinson, Dana H.; Thompson, Nancy J.; Perryman, Jennie P.

2010-01-01

This study sought to evaluate the effectiveness of "Project ACTS: About Choices in Transplantation and Sharing," which was developed to increase readiness for organ and tissue donation among African American adults. Nine churches (N = 425 participants) were randomly assigned to receive donation education materials currently available to consumers…

A Radially Organized Multipatterned Device as a Diagnostic Tool for the Screening of Topographies in Tissue Engineering Biomaterials

NARCIS (Netherlands)

Babo, P.S.; Klymov, A.; Riet, J. te; Reis, R.L.; Jansen, J.A.; Gomes, M.E.; Walboomers, X.F.

2016-01-01

Micro- and nanotextured biomaterial surfaces have been widely studied for their capacity to drive the regeneration of organized tissues. Nanotopographical features in the shape of groove-ridge patterns aim at mimicking the extracellular matrix organization. However, to date, a wide array of groove

TISSUES 2.0: an integrative web resource on mammalian tissue expression.

Science.gov (United States)

Palasca, Oana; Santos, Alberto; Stolte, Christian; Gorodkin, Jan; Jensen, Lars Juhl

2018-01-01

Physiological and molecular similarities between organisms make it possible to translate findings from simpler experimental systems—model organisms—into more complex ones, such as human. This translation facilitates the understanding of biological processes under normal or disease conditions. Researchers aiming to identify the similarities and differences between organisms at the molecular level need resources collecting multi-organism tissue expression data. We have developed a database of gene–tissue associations in human, mouse, rat and pig by integrating multiple sources of evidence: transcriptomics covering all four species and proteomics (human only), manually curated and mined from the scientific literature. Through a scoring scheme, these associations are made comparable across all sources of evidence and across organisms. Furthermore, the scoring produces a confidence score assigned to each of the associations. The TISSUES database (version 2.0) is publicly accessible through a user-friendly web interface and as part of the STRING app for Cytoscape. In addition, we analyzed the agreement between datasets, across and within organisms, and identified that the agreement is mainly affected by the quality of the datasets rather than by the technologies used or organisms compared. http://tissues.jensenlab.org/

Enhanced contractile force generation by artificial skeletal muscle tissues using IGF-I gene-engineered myoblast cells.

Science.gov (United States)

Sato, Masanori; Ito, Akira; Kawabe, Yoshinori; Nagamori, Eiji; Kamihira, Masamichi

2011-09-01

The aim of this study was to investigate whether insulin-like growth factor (IGF)-I gene delivery to myoblast cells promotes the contractile force generated by hydrogel-based tissue-engineered skeletal muscles in vitro. Two retroviral vectors allowing doxycycline (Dox)-inducible expression of the IGF-I gene were transduced into mouse myoblast C2C12 cells to evaluate the effects of IGF-I gene expression on these cells. IGF-I gene expression stimulated the proliferation of C2C12 cells, and a significant increase in the growth rate was observed for IGF-I-transduced C2C12 cells with Dox addition, designated C2C12/IGF (Dox+) cells. Quantitative morphometric analyses showed that the myotubes induced from C2C12/IGF (Dox+) cells had a larger area and a greater width than control myotubes induced from normal C2C12 cells. Artificial skeletal muscle tissues were prepared from the respective cells using hydrogels composed of type I collagen and Matrigel. Western blot analyses revealed that the C2C12/IGF (Dox+) tissue constructs showed activation of a skeletal muscle hypertrophy marker (Akt) and enhanced expression of muscle-specific markers (myogenin, myosin heavy chain and tropomyosin). Moreover, the creatine kinase activity was increased in the C2C12/IGF (Dox+) tissue constructs. The C2C12/IGF (Dox+) tissue constructs contracted in response to electrical pulses, and generated a significantly higher physical force than the control C2C12 tissue constructs. These findings indicate that IGF-I gene transfer has the potential to yield functional skeletal muscle substitutes that are capable of in vivo restoration of the load-bearing function of injured muscle or acting as in vitro electrically-controlled bio-actuators. Copyright © 2011 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

Recruitment Kinetics of Tropomyosin Tpm3.1 to Actin Filament Bundles in the Cytoskeleton Is Independent of Actin Filament Kinetics.

Science.gov (United States)

Appaduray, Mark A; Masedunskas, Andrius; Bryce, Nicole S; Lucas, Christine A; Warren, Sean C; Timpson, Paul; Stear, Jeffrey H; Gunning, Peter W; Hardeman, Edna C

2016-01-01

The actin cytoskeleton is a dynamic network of filaments that is involved in virtually every cellular process. Most actin filaments in metazoa exist as a co-polymer of actin and tropomyosin (Tpm) and the function of an actin filament is primarily defined by the specific Tpm isoform associated with it. However, there is little information on the interdependence of these co-polymers during filament assembly and disassembly. We addressed this by investigating the recovery kinetics of fluorescently tagged isoform Tpm3.1 into actin filament bundles using FRAP analysis in cell culture and in vivo in rats using intracellular intravital microscopy, in the presence or absence of the actin-targeting drug jasplakinolide. The mobile fraction of Tpm3.1 is between 50% and 70% depending on whether the tag is at the C- or N-terminus and whether the analysis is in vivo or in cultured cells. We find that the continuous dynamic exchange of Tpm3.1 is not significantly impacted by jasplakinolide, unlike tagged actin. We conclude that tagged Tpm3.1 may be able to undergo exchange in actin filament bundles largely independent of the assembly and turnover of actin.

Controlling human corneal stromal stem cell contraction to mediate rapid cell and matrix organization of real architecture for 3-dimensional tissue equivalents.

Science.gov (United States)

Mukhey, Dev; Phillips, James B; Daniels, Julie T; Kureshi, Alvena K

2018-02-01

The architecture of the human corneal stroma consists of a highly organized extracellular matrix (ECM) interspersed with keratocytes. Their progenitor cells; corneal stromal stem cells (CSSC) are located at the periphery, in the limbal stroma. A highly organized corneal ECM is critical for effective transmission of light but this structure may be compromised during injury or disease, resulting in loss of vision. Re-creating normal organization in engineered tissue equivalents for transplantation often involves lengthy culture times that are inappropriate for clinical use or utilisation of synthetic substrates that bring complications such as corneal melting. CSSC have great therapeutic potential owing to their ability to reorganize a disorganized matrix, restoring transparency in scarred corneas. We examined CSSC contractile behavior to assess whether this property could be exploited to rapidly generate cell and ECM organization in Real Architecture For 3D Tissues (RAFT) tissue equivalents (TE) for transplantation. Free-floating collagen gels were characterized to assess contractile behavior of CSSC and establish optimum cell density and culture times. To mediate cell and collagen organization, tethered collagen gels seeded with CSSC were cultured and subsequently stabilized with the RAFT process. We demonstrated rapid creation of biomimetic RAFT TE with tunable structural properties. These displayed three distinct regions of varying degrees of cellular and collagen organization. Interestingly, increased organization coincided with a dramatic loss of PAX6 expression in CSSC, indicating rapid differentiation into keratocytes. The organized RAFT TE system could be a useful bioengineering tool to rapidly create an organized ECM while simultaneously controlling cell phenotype. For the first time, we have demonstrated that human CSSC exhibit the phenomenon of cellular self-alignment in tethered collagen gels. We found this mediated rapid co-alignment of collagen fibrils

PCBs and PCDD/Fs distribution in tissues and organs of marine animals in Russian Arctic

Energy Technology Data Exchange (ETDEWEB)

Amirova, Z.; Kruglov, E.; Loshkina, E.; Khalilov, R. [Environmental Research and Protection Centre, Ufa (Russian Federation); Melnikov, S.; Vlasov, S. [Regional Centre Monitoring of the Arctic, St. Petersburg (Russian Federation)

2004-09-15

Studies of persistent organic pollutants (POPs) in the Russian Arctic were conducted recently by a Arctic Monitoring and Assessment Program (AMAP) project. This project developed new data on the POPs pollution levels in the environment and biosphere, including PCBs and PCDD/Fs, in arctic regions of Russia. Transboundary transport and biomagnification within food chains in arctic regions result in POPs accumulation in tissues of fish and marine animals. The aim of this study was to determine the concentration of indicator PCBs, co-planar PCBs and PCDD/Fs in different tissues and organs of seals, walruses and whales caught near the seashore of Chukotski Peninsula (settlement of Lavrenty), Russia, to determine the background level of arctic biota pollution and to study distribution of toxicants in organisms of marine animals. Sampling was made in the course of the 1{sup st} and the 2{sup nd} stages of the 4{sup th} phase of Raipon/AMAP/GEF project ''Persistent Toxic Substances (PTS), Food Security and Indigenous Peoples of the Russian North'' in 2002 by researchers of the Regional Center for Monitoring of the Arctic (RCMA), St. Petersburg, Russia.

Factors influencing the results of tissue and organ donation: a survey from Cho Ray hospital Mortuary in Ho Chi Minh City, Vietnam

International Nuclear Information System (INIS)

Tran Cong Toai; Hoang Van Thuc; Nguyen Ngoc Son; Pham Anh Tuan; Yongyudh Vajaradul; Tran Bac Hai; Nguyen Giang Son; Hyunh Ngoc Linh

1999-01-01

The study was carried out on next-of-kins of the deceased one to identify factors affecting the final results of organ donation. Among 225 interviewers (67.1% men), 80 people (35.6%) would be willing to give consent for donation of their relative's tissue and organ. When faced with the beloved death, only 8 cases were procured in reality. The obstacles that limited the organ procurement are due to: consent with some conditions (26/80); not the right relative available to make consent (25/80); initial consent subsequently withdrawn (12/80); exclusion criteria by Tissue Bank (7/80) and interview too late (2/80). There were 62.2% of respondents heard about tissue and organ transplantation, but only 50.3% were aware of transplantation operations possible in Viet Nam. Awareness of transplantation and donation revealed the statistically significant association with the consent for organ donation. It is important that these all such factors need to be considered in their cultural, ethical, religious and legislative environment

Impact of tissue surface properties on the desorption electrospray ionization imaging of organic acids in grapevine stem.

Science.gov (United States)

Dong, Yonghui; Guella, Graziano; Franceschi, Pietro

2016-03-30

Desorption electrospray ionization (DESI) imaging is a fast analytical technique used to assess spatially resolved biological processes over unmodified sample surfaces. Although DESI profiling experiments have demonstrated that the properties of the sample surface significantly affect the outcomes of DESI analyses, the potential implications of these phenomena in imaging applications have not yet been explored extensively. The distribution of endogenous and exogenous organic acids in pith and out pith region of grapevine stems was investigated by using DESI imaging, ion chromatography and direct infusion methods. Several common normalization strategies to account for the surface effect, including TIC normalization, addition of the internal standard in the spray solvent and deposition of the standard over the sample surface, were critically evaluated. DESI imaging results show that, in our case, the measured distributions of these small organic acids are not consistent with their 'true' localizations within the tissues. Furthermore, our results indicate that the common normalization strategies are not able to completely compensate for the observed surface effect. Variations in the tissue surface properties across the tissue sample can greatly affect the semi-quantitative detection of organic acids. Attention should be paid when interpreting DESI imaging results and an independent analytical validation step is important in untargeted DESI imaging investigations. Copyright © 2016 John Wiley & Sons, Ltd.

Cardiac troponin and tropomyosin: structural and cellular perspectives to unveil the Hypertrophic Cardiomyopathy phenotype

Directory of Open Access Journals (Sweden)

Mayra de A. Marques

2016-09-01

Full Text Available Inherited myopathies affect both skeletal and cardiac muscle and are commonly associated with genetic dysfunctions, leading to the production of anomalous proteins. In cardiomyopathies, mutations frequently occur in sarcomeric genes, but the cause-effect scenario between genetic alterations and pathological processes remains elusive. Hypertrophic cardiomyopathy (HCM was the first cardiac disease associated with a genetic background. Since the discovery of the first mutation in the β-myosin heavy chain, more than 1,400 new mutations in 11 sarcomeric genes have been reported, awarding HCM the title of the disease of the sarcomere. The most common macroscopic phenotypes are left ventricle and interventricular septal thickening, but because the clinical profile of this disease is quite heterogeneous, these phenotypes are not suitable for an accurate diagnosis. The development of genomic approaches for clinical investigation allows for diagnostic progress and understanding at the molecular level. Meanwhile, the lack of accurate in vivo models to better comprehend the cellular events triggered by this pathology has become a challenge. Notwithstanding, the imbalance of Ca2+ concentrations, altered signaling pathways, induction of apoptotic factors, and heart remodeling leading to abnormal anatomy have already been reported. Of note, a misbalance of signaling biomolecules, such as kinases and tumor suppressors (e.g., Akt and p53, seems to participate in apoptotic and fibrotic events. In HCM, structural and cellular information about defective sarcomeric proteins and their altered interactome is emerging but still represents a bottleneck for developing new concepts in basic research and for future therapeutic interventions. This review focuses on the structural and cellular alterations triggered by HCM-causing mutations in troponin and tropomyosin proteins and how structural biology can aid in the discovery of new platforms for therapeutics. We

Heavy metal distribution in organic and siliceous marine sponge tissues measured by square wave anodic stripping voltammetry.

Science.gov (United States)

Illuminati, S; Annibaldi, A; Truzzi, C; Scarponi, G

2016-10-15

May sponge spicules represent a "tank" to accumulate heavy metals? In this study we test this hypothesis determining the distribution of Cd, Pb and Cu concentrations between organic and siliceous tissues in Antarctic Demospongia (Sphaerotylus antarcticus, Kirkpatrikia coulmani and Haliclona sp.) and in the Mediterranean species Petrosia ficiformis. Results show that although, in these sponges, spicules represent about 80% of the mass content, the accumulation of pollutant is lower in the spicules than in the corresponding organic fraction. The contribution of tissues to the total sponge content of Cd, Pb and Cu is respectively 99%, 82% and 97% for Antarctic sponges and 96%, 95% and 96% for P. ficiformis, similar in polar and temperate organisms. These results pave the way to a better understanding of the role of marine sponges in uptaking heavy metals and to their possible use as monitor of marine ecosystems, recommend by the Water Framework Directive. Copyright © 2016 Elsevier Ltd. All rights reserved.

Adipose Tissue as an Endocrine Organ: An Update on Pro-inflammatory and Anti-inflammatory Microenvironment

Directory of Open Access Journals (Sweden)

Kvido Smitka

2015-01-01

Full Text Available Adipose tissue is recognized as an active endocrine organ that produces a number of endocrine substances referred to as “adipokines” including leptin, adiponectin, adipolin, visfatin, omentin, tumour necrosis factor-alpha (TNF-α, interleukin-6 (IL-6, resistin, pigment epithelium-derived factor (PEDF, and progranulin (PGRN which play an important role in the food intake regulation and significantly influence insulin sensitivity and in some cases directly affect insulin resistance in skeletal muscle, liver, and adipose tissue. The review summarizes current knowledge about adipose tissue-derived hormones and their influence on energy homeostasis regulation. The possible therapeutic potential of these adipokines in the treatment of insulin resistance, endothelial dysfunction, a pro-inflammatory response, obesity, eating disorders, progression of atherosclerosis, type 1 diabetes, and type 2 diabetes is discussed.

Integrity of the oral tissues in patients with solid-organ transplants.

Science.gov (United States)

Rojas, Gonzalo; Bravo, Loreto; Cordero, Karina; Sepúlveda, Luis; Elgueta, Leticia; Díaz, Juan Carlos; Urzúa, Blanca; Morales, Irene

2012-01-01

The relationship between the use of immunosuppressants in solid-organ transplant patients and oral tissue abnormalities has been recognized. The objective of this study was to determine the state of oral tissue integrity in renal, heart, and liver transplant patients who are on continuous medical and dental control. Forty patients of both sexes were clinically evaluated at the Clinical Hospital of the University of Chile to identify pathologies of oral mucosa, gingival enlargement (GE), decayed, missing, filled teeth (DMFT) index, and salivary flow. The average age of the transplant subjects was 49.4 years, and the age range was 19 to 69 years. Most subjects maintained a good level of oral hygiene, and the rate mean of DMFT was 14.7. The degree of involvement of the oral mucosa and GE was low (10%). Unlike other studies, the frequency of oral mucosal diseases and GE was low despite the fact that these patients were immunosuppressed. Care and continuous monitoring seem to be of vital importance in maintaining the oral health of transplant patients.

Integrity of the Oral Tissues in Patients with Solid-Organ Transplants

Directory of Open Access Journals (Sweden)

Gonzalo Rojas

2012-01-01

Full Text Available The relationship between the use of immunosuppressants in solid-organ transplant patients and oral tissue abnormalities has been recognized. The objective of this study was to determine the state of oral tissue integrity in renal, heart, and liver transplant patients who are on continuous medical and dental control. Forty patients of both sexes were clinically evaluated at the Clinical Hospital of the University of Chile to identify pathologies of oral mucosa, gingival enlargement (GE, decayed, missing, filled teeth (DMFT index, and salivary flow. The average age of the transplant subjects was 49.4 years, and the age range was 19 to 69 years. Most subjects maintained a good level of oral hygiene, and the rate mean of DMFT was 14.7. The degree of involvement of the oral mucosa and GE was low (10%. Unlike other studies, the frequency of oral mucosal diseases and GE was low despite the fact that these patients were immunosuppressed. Care and continuous monitoring seem to be of vital importance in maintaining the oral health of transplant patients.

Pharmacokinetic study of arctigenin in rat plasma and organ tissue by RP-HPLC method.

Science.gov (United States)

He, Fan; Dou, De-Qiang; Hou, Qiang; Sun, Yu; Kang, Ting-Guo

2013-01-01

A high-performance liquid chromatography (HPLC) technique was developed for the determination of arctigenin in plasma and various organs of rats after the oral administration of 30, 50 and 70 mgkg(-1) of arctigenin to the Sprague-Dawley rats. Results showed that the validated HPLC method was simple, fast, reproducible and suitable to the determination of arctigenin in rat plasma and organ tissue and one-compartmental model with zero-order absorption process can well describe the changes of arctigenin concentration in the plasma. The concentration of compound was highest in the spleen, less in the liver and the least in the lung.

Plant tissue culture techniques

Directory of Open Access Journals (Sweden)

Rolf Dieter Illg

1991-01-01

Full Text Available Plant cell and tissue culture in a simple fashion refers to techniques which utilize either single plant cells, groups of unorganized cells (callus or organized tissues or organs put in culture, under controlled sterile conditions.

Levels of Cs-137 and pathological shifts in the organs and tissues of dead humans

International Nuclear Information System (INIS)

Lushnikov, E.F.; Koleganov, Yu.F.; Lantsov, S.I.; Mozhaev, V.K.; Solov'eva, L.P.; Fomin, S.D.

1996-01-01

Measurements of the levels of Cs-137, alpha- and beta-radionuclides in the organs and tissues of 30 subjects dead 6 years after the accident, assessment of the pathological shifts and relationships between these shifts and exposure was carried out at territories contaminated with radionuclides in the Bryansk and Kaluga districts, in the town of Obninsk, and in region of Russia free of radionuclides. Study of radioautographs did not show alpha- or beta-radionuclides in any of the dead subjects. Cs-137 was detected in small quantities in the organs of all cadavers (3 to 424 Bq/kg) irrespective of their residence. The extent of radioactivity varied for different organs and was unrelated to organ pathology. Moreover, Cs-137 was detected in the organs of dead newborns and two-month-old infants, whose patients lived at territories contaminated with radionuclides [ru

Localization of brain-derived neurotrophic factor, neurotrophin-4, tropomyosin-related kinase b receptor, and p75 NTR receptor by high-resolution immunohistochemistry on the adult mouse neuromuscular junction.

Science.gov (United States)

Garcia, Neus; Tomàs, Marta; Santafe, Manel M; Lanuza, M Angel; Besalduch, Nuria; Tomàs, Josep

2010-03-01

Neurotrophins and their receptors, the trk receptor tyrosine kinases (trks) and p75(NTR), are differentially expressed among the cell types that make up synapses. It is important to determine the precise location of these molecules involved in neurotransmission. Here we use immunostaining and Western blotting to study the localization and expression of neurotrophin brain-derived neurotrophic factor (BDNF) and neurotrophin-4 (NT-4) and the receptors tropomyosin-related kinase b (trkB) and p75(NTR) at the adult neuromuscular junction. Our confocal immunofluorescence results on the whole mounts of the mouse Levator auris longus muscle and on semithin cross-sections showed that BDNF, NT-4, trkB, and p75(NTR) were localized on the three cells in the neuromuscular synapse (motor axons, post-synaptic muscle and Schwann cells).

Evaluation of Specific Metabolic Rates of Major Organs and Tissues: Comparison Between Nonobese and Obese Women

OpenAIRE

Wang, ZiMian; Ying, Zhiliang; Bosy-Westphal, Anja; Zhang, Junyi; Heller, Martin; Later, Wiebke; Heymsfield, Steven B.; Müller, Manfred J.

2011-01-01

Elia (1992) identified the specific resting metabolic rates (Ki) of major organs and tissues in young adults with normal weight: 200 for liver, 240 for brain, 440 for heart and kidneys, 13 for skeletal muscle, 4.5 for adipose tissue and 12 for residual mass (all units in kcal/kg per day). The aim of the present study was to assess the applicability of Elia’s Ki values for obese adults. A sample of young women (n = 80) was divided into two groups, nonobese (BMI

Organ Donation

Science.gov (United States)

Organ donation takes healthy organs and tissues from one person for transplantation into another. Experts say that the organs ... and bone marrow Cornea Most organ and tissue donations occur after the donor has died. But some ...

Tissue bionics: examples in biomimetic tissue engineering

Energy Technology Data Exchange (ETDEWEB)

Green, David W [Bone and Joint Research Group, Developmental Origins of Health and Disease, General Hospital, University of Southampton, SO16 6YD (United Kingdom)], E-mail: Hindoostuart@googlemail.com

2008-09-01

Many important lessons can be learnt from the study of biological form and the functional design of organisms as design criteria for the development of tissue engineering products. This merging of biomimetics and regenerative medicine is termed 'tissue bionics'. Clinically useful analogues can be generated by appropriating, modifying and mimicking structures from a diversity of natural biomatrices ranging from marine plankton shells to sea urchin spines. Methods in biomimetic materials chemistry can also be used to fabricate tissue engineering scaffolds with added functional utility that promise human tissues fit for the clinic.

Tissue bionics: examples in biomimetic tissue engineering

International Nuclear Information System (INIS)

Green, David W

2008-01-01

Many important lessons can be learnt from the study of biological form and the functional design of organisms as design criteria for the development of tissue engineering products. This merging of biomimetics and regenerative medicine is termed 'tissue bionics'. Clinically useful analogues can be generated by appropriating, modifying and mimicking structures from a diversity of natural biomatrices ranging from marine plankton shells to sea urchin spines. Methods in biomimetic materials chemistry can also be used to fabricate tissue engineering scaffolds with added functional utility that promise human tissues fit for the clinic

The importance of the selection of the audiences and the organization of media events within public awareness strategies for tissue banks.

Science.gov (United States)

Morales Pedraza, Jorge

2008-12-01

The main purpose of the International Atomic Energy Agency (IAEA) Public Awareness Strategies for Tissue Banks is to provide guidance on organizing and running awareness campaigns, in order to consolidate tissue banking activities. Within the IAEA Public Awareness Strategies for Tissue Banks, there are two important topics, which need to be singled out due to their importance for a successful public and professional awareness campaign. These are the selection of the audiences and the organization of media events within a Communication Strategy. The experience in the field of tissue banking in several countries has shown that interaction between the public, the professional health care staff, the media and the tissue bank personnel is essential if the activities of the banks are to be successful. It must be emphasized however, that any public and professional awareness strategy will not be successful, unless it is considered as part of an integrated system that is adopted by the concerned Government.

Hardwiring stem cell communication through tissue structure

Science.gov (United States)

Xin, Tianchi; Greco, Valentina; Myung, Peggy

2016-01-01

Adult stem cells across diverse organs self-renew and differentiate to maintain tissue homeostasis. How stem cells receive input to preserve tissue structure and function largely relies on their communication with surrounding cellular and non-cellular elements. As such, how tissues are organized and patterned not only reflects organ function but also inherently hardwires networks of communication between stem cells and their environment to direct tissue homeostasis and injury repair. This review highlights how different methods of stem cell communication reflect the unique organization and function of diverse tissues. PMID:26967287

Classification of trace elements in tissues from organic and conventional French pig production.

Science.gov (United States)

Parinet, Julien; Royer, Eric; Saint-Hilaire, Mailie; Chafey, Claude; Noël, Laurent; Minvielle, Brice; Dervilly-Pinel, Gaud; Engel, Erwan; Guérin, Thierry

2018-07-01

This study assesses the impact of the farming system on the levels of copper, zinc, arsenic, cadmium, lead and mercury in pig tissues from three types of production (Organic (n = 28), Label Rouge (n = 12) and Conventional (n = 30)) randomly sampled in different slaughterhouses. All the concentrations were below regulatory limits. In muscles, Cu, Zn and As were measured at slightly higher levels in organic samples but no differences between organic and Label Rouge was observed. Livers from conventional and Label Rouge pig farms exhibited higher Zn and Cd contents than the organic ones, probably due to different practice in zinc or phytase supplementation of fattening diets. Principal component analysis indicated a correlation between Cu and As concentrations in liver and carcass weight, and between Zn and Cd liver levels and lean meat percentage. The linear discriminant analysis succeeded in predicting the farming process on the basis of the lean meat percentage and the liver Cd level. Copyright © 2018 Elsevier Ltd. All rights reserved.

West Nile Virus RNA in Tissues from Donor Associated with Transmission to Organ Transplant Recipients

Centers for Disease Control (CDC) Podcasts

2013-11-19

William Hale reads an abridged version of the Emerging Infectious Diseases’ dispatch, West Nile Virus RNA in Tissues from Donor Associated with Transmission to Organ Transplant Recipients.  Created: 11/19/2013 by National Center for Emerging and Zoonotic Infectious Diseases (NCEZID).   Date Released: 11/21/2013.

Additive Manufacturing of Biomaterials, Tissues, and Organs.

Science.gov (United States)

Zadpoor, Amir A; Malda, Jos

2017-01-01

The introduction of additive manufacturing (AM), often referred to as three-dimensional (3D) printing, has initiated what some believe to be a manufacturing revolution, and has expedited the development of the field of biofabrication. Moreover, recent advances in AM have facilitated further development of patient-specific healthcare solutions. Customization of many healthcare products and services, such as implants, drug delivery devices, medical instruments, prosthetics, and in vitro models, would have been extremely challenging-if not impossible-without AM technologies. The current special issue of the Annals of Biomedical Engineering presents the latest trends in application of AM techniques to healthcare-related areas of research. As a prelude to this special issue, we review here the most important areas of biomedical research and clinical practice that have benefited from recent developments in additive manufacturing techniques. This editorial, therefore, aims to sketch the research landscape within which the other contributions of the special issue can be better understood and positioned. In what follows, we briefly review the application of additive manufacturing techniques in studies addressing biomaterials, (re)generation of tissues and organs, disease models, drug delivery systems, implants, medical instruments, prosthetics, orthotics, and AM objects used for medical visualization and communication.

Hardwiring Stem Cell Communication through Tissue Structure.

Science.gov (United States)

Xin, Tianchi; Greco, Valentina; Myung, Peggy

2016-03-10

Adult stem cells across diverse organs self-renew and differentiate to maintain tissue homeostasis. How stem cells receive input to preserve tissue structure and function largely relies on their communication with surrounding cellular and non-cellular elements. As such, how tissues are organized and patterned not only reflects organ function, but also inherently hardwires networks of communication between stem cells and their environment to direct tissue homeostasis and injury repair. This review highlights how different methods of stem cell communication reflect the unique organization and function of diverse tissues. Copyright © 2016 Elsevier Inc. All rights reserved.

A Review on the 3D Printing of Functional Structures for Medical Phantoms and Regenerated Tissue and Organ Applications

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Kan Wang

2017-10-01

Full Text Available Medical models, or “phantoms,” have been widely used for medical training and for doctor-patient interactions. They are increasingly used for surgical planning, medical computational models, algorithm verification and validation, and medical devices development. Such new applications demand high-fidelity, patient-specific, tissue-mimicking medical phantoms that can not only closely emulate the geometric structures of human organs, but also possess the properties and functions of the organ structure. With the rapid advancement of three-dimensional (3D printing and 3D bioprinting technologies, many researchers have explored the use of these additive manufacturing techniques to fabricate functional medical phantoms for various applications. This paper reviews the applications of these 3D printing and 3D bioprinting technologies for the fabrication of functional medical phantoms and bio-structures. This review specifically discusses the state of the art along with new developments and trends in 3D printed functional medical phantoms (i.e., tissue-mimicking medical phantoms, radiologically relevant medical phantoms, and physiological medical phantoms and 3D bio-printed structures (i.e., hybrid scaffolding materials, convertible scaffolds, and integrated sensors for regenerated tissues and organs.

Whole-organ isolation approach as a basis for tissue-specific analyses in Schistosoma mansoni.

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Steffen Hahnel

Full Text Available BACKGROUND: Schistosomiasis is one of the most important parasitic diseases worldwide, second only to malaria. Schistosomes exhibit an exceptional reproductive biology since the sexual maturation of the female, which includes the differentiation of the reproductive organs, is controlled by pairing. Pathogenicity originates from eggs, which cause severe inflammation in their hosts. Elucidation of processes contributing to female maturation is not only of interest to basic science but also considering novel concepts combating schistosomiasis. METHODOLOGY/PRINCIPAL FINDINGS: To get direct access to the reproductive organs, we established a novel protocol using a combined detergent/protease-treatment removing the tegument and the musculature of adult Schistosoma mansoni. All steps were monitored by scanning electron microscopy (SEM and bright-field microscopy (BF. We focused on the gonads of adult schistosomes and demonstrated that isolated and purified testes and ovaries can be used for morphological and structural studies as well as sources for RNA and protein of sufficient amounts for subsequent analyses such as RT-PCR and immunoblotting. To this end, first exemplary evidence was obtained for tissue-specific transcription within the gonads (axonemal dynein intermediate chain gene SmAxDynIC; aquaporin gene SmAQP as well as for post-transcriptional regulation (SmAQP. CONCLUSIONS/SIGNIFICANCE: The presented method provides a new way of getting access to tissue-specific material of S. mansoni. With regard to many still unanswered questions of schistosome biology, such as elucidating the molecular processes involved in schistosome reproduction, this protocol provides opportunities for, e.g., sub-transcriptomics and sub-proteomics at the organ level. This will promote the characterisation of gene-expression profiles, or more specifically to complete knowledge of signalling pathways contributing to differentiation processes, so discovering involved

Designing and modeling of complex DNA vaccine based on tropomyosin protein of Boophilus genus tick.

Science.gov (United States)

Ranjbar, Mohamamd Mahdi; Gupta, Shishir K; Ghorban, Khodayar; Nabian, Sedigheh; Sazmand, Alireza; Taheri, Mohammad; Esfandyari, Sahar; Taheri, Maryam

2015-01-01

Boophilus tick is a bloodsucking ectoparasite that transfers some pathogens, reducing production and thus leading to economical losses in the cattle industry. Tropomyosin (TPM) protein is a salivary protein, has actin regulator activity, and plays an important role in immune reactions against parasites. In the current study, besides developing a safe, effective, and broad spectrum protective measure against Boophilus genus tick based on TPM protein, we attempted to minimize possible problems occurring in the design of polytopic vaccines. Briefly, the steps that were followed in the present study were as follows: retrieving sequences and finding the mutational/conservative regions, selecting consensus and high immunogenic epitopes of B and CD4(+) T cells by different approaches, three-dimensional structure (3D structure) prediction and representation of epitopes and highly variable/conserve regions, designing vaccinal construct by fusion of B and T cell epitopes by special patterns and improving immunogenicity, evaluation of the constructs' primary structure and posttranslational modification, calculation of hydrophobic regions, reverse translation, codon optimization, open reading frame checking, insertion of start/end codon, Kozak sequence, and finally constructing the DNA vaccine. Variation plot showed some shared epitopes among the ticks' and mites' species that some might be effective only in some species. Finally, by following the steps mentioned above, two constructs for B and T cells were achieved. Checking constructs revealed their reliability and efficacy for in vitro production and utilization. Successful in silico modeling is an essential step of designing vigorous vaccines. We developed a novel protective and therapeutic vaccine against Boophilus genus (based on TPM protein). At the next step, constructed DNA vaccine would be produced in vitro and administrated to cattle, and its potency to induction of immune response and protection against Boophilus

IgA class switch occurs in the organized nasopharynx- and gut-associated lymphoid tissue, but not in the diffuse lamina propria of airways and gut.

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Shikina, Takashi; Hiroi, Takachika; Iwatani, Kohichi; Jang, Myoung Ho; Fukuyama, Satoshi; Tamura, Manabu; Kubo, Takeshi; Ishikawa, Hiromichi; Kiyono, Hiroshi

2004-05-15

Secretory IgA plays a crucial role in the host immune response as a first line of defense. A recent demonstration of in situ IgA class switching in intestinal lamina propria provided an opportunity to reconsider the model for the homing of IgA-committed B cells characterized by distinctive trafficking patterns to effector sites. Those effector sites depend on the organized mucosa-associated lymphoid tissues as their site of induction. In this report we show the preferential presence of IgM(+)B220(+) and IgA(+)B220(+) cells belonging to pre- and post-IgA isotype class-switched cells in the organized mucosa-associated lymphoid tissues, such as nasopharynx-associated lymphoid tissues, isolated lymphoid follicles, and Peyer's patches, and the defect of those populations in the diffuse effector tissues, such as the nasal passage and intestinal lamina propria. Consistent with these findings, the expressions of a series of IgA isotype class switch recombination-related molecules, including activation-induced cytidine deaminase, Ialpha-C micro circle transcripts, and Ialpha-C micro circle transcripts, were selectively detected in these organized mucosa-associated lymphoid structures, but not in the diffuse mucosal effector sites. Taken together, these findings suggest that IgA isotype class switching occurs only in the organized mucosa-associated lymphoid organs (e.g., nasopharynx-associated lymphoid tissues, isolated lymphoid follicles, and Peyer's patches), but not in the diffuse effector tissues of the upper respiratory and gastrointestinal tracts.

Tritium metabolism in rat tissues

International Nuclear Information System (INIS)

Takeda, H.

1982-01-01

As part of a series of studies designed to evaluate the relative radiotoxicity of various tritiated compounds, metabolism of tritium in rat tissues was studied after administration of tritiated water, leucine, thymidine, and glucose. The distribution and retention of tritium varied widely, depending on the chemical compound administered. Tritium introduced as tritiated water behaved essentially as body water and became uniformly distributed among the tissues. However, tritium administered as organic compounds resulted in relatively high incorporation into tissue constituents other than water, and its distribution differed among the various tissues. Moreover, the excretion rate of tritium from tissues was slower for tritiated organic compounds than for tritiated water. Administrationof tritiated organic compounds results in higher radiation doses to the tissues than does administration of tritiated water. Among the tritiated compounds examined, for equal radioactivity administered, leucine gave the highest radiation dose, followed in turn by thymidine, glucose, and water. (author)

3D Printer Generated Tissue iMolds for Cleared Tissue Using Single- and Multi-Photon Microscopy for Deep Tissue Evaluation.

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Miller, Sean J; Rothstein, Jeffrey D

2017-01-01

Pathological analyses and methodology has recently undergone a dramatic revolution. With the creation of tissue clearing methods such as CLARITY and CUBIC, groups can now achieve complete transparency in tissue samples in nano-porous hydrogels. Cleared tissue is then imagined in a semi-aqueous medium that matches the refractive index of the objective being used. However, one major challenge is the ability to control tissue movement during imaging and to relocate precise locations post sequential clearing and re-staining. Using 3D printers, we designed tissue molds that fit precisely around the specimen being imaged. First, images are taken of the specimen, followed by importing and design of a structural mold, then printed with affordable plastics by a 3D printer. With our novel design, we have innovated tissue molds called innovative molds (iMolds) that can be generated in any laboratory and are customized for any organ, tissue, or bone matter being imaged. Furthermore, the inexpensive and reusable tissue molds are made compatible for any microscope such as single and multi-photon confocal with varying stage dimensions. Excitingly, iMolds can also be generated to hold multiple organs in one mold, making reconstruction and imaging much easier. Taken together, with iMolds it is now possible to image cleared tissue in clearing medium while limiting movement and being able to relocate precise anatomical and cellular locations on sequential imaging events in any basic laboratory. This system provides great potential for screening widespread effects of therapeutics and disease across entire organ systems.

Proteomic Analysis of Lysine Acetylation Sites in Rat Tissues Reveals Organ Specificity and Subcellular Patterns

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Alicia Lundby

2012-08-01

Full Text Available Lysine acetylation is a major posttranslational modification involved in a broad array of physiological functions. Here, we provide an organ-wide map of lysine acetylation sites from 16 rat tissues analyzed by high-resolution tandem mass spectrometry. We quantify 15,474 modification sites on 4,541 proteins and provide the data set as a web-based database. We demonstrate that lysine acetylation displays site-specific sequence motifs that diverge between cellular compartments, with a significant fraction of nuclear sites conforming to the consensus motifs G-AcK and AcK-P. Our data set reveals that the subcellular acetylation distribution is tissue-type dependent and that acetylation targets tissue-specific pathways involved in fundamental physiological processes. We compare lysine acetylation patterns for rat as well as human skeletal muscle biopsies and demonstrate its general involvement in muscle contraction. Furthermore, we illustrate that acetylation of fructose-bisphosphate aldolase and glycerol-3-phosphate dehydrogenase serves as a cellular mechanism to switch off enzymatic activity.

Registry of Hospital das Clínicas of the University of São Paulo Medical School: first official solid organ and tissue transplantation report - 2008

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Estela Azeka

2009-02-01

Full Text Available OBJECTIVE: The aim of this study was to report a single center experience of organ and tissue transplantation INTRODUCTION: This is the first report of organ and tissue transplantation at the Hospital das Clínicas of the University of Sao Paulo Medical School. METHODS: We collected data from each type of organ transplantation from 2002 to 2007. The data collected were patient characteristics and actuarial survival Kaplan-Meier curves at 30 days, one year, and five years RESULTS: There were a total of 3,321 transplants at our institution and the 5-year survival curve ranged from 53% to 88%. CONCLUSION: This report shows that solid organ and tissue transplants are feasible within the institution and allow us to expect that the quality of transplantation will improve in the future.

A fish-feeding laboratory bioassay to assess the antipredatory activity of secondary metabolites from the tissues of marine organisms.

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Marty, Micah J; Pawlik, Joseph R

2015-01-11

Marine chemical ecology is a young discipline, having emerged from the collaboration of natural products chemists and marine ecologists in the 1980s with the goal of examining the ecological functions of secondary metabolites from the tissues of marine organisms. The result has been a progression of protocols that have increasingly refined the ecological relevance of the experimental approach. Here we present the most up-to-date version of a fish-feeding laboratory bioassay that enables investigators to assess the antipredatory activity of secondary metabolites from the tissues of marine organisms. Organic metabolites of all polarities are exhaustively extracted from the tissue of the target organism and reconstituted at natural concentrations in a nutritionally appropriate food matrix. Experimental food pellets are presented to a generalist predator in laboratory feeding assays to assess the antipredatory activity of the extract. The procedure described herein uses the bluehead, Thalassoma bifasciatum, to test the palatability of Caribbean marine invertebrates; however, the design may be readily adapted to other systems. Results obtained using this laboratory assay are an important prelude to field experiments that rely on the feeding responses of a full complement of potential predators. Additionally, this bioassay can be used to direct the isolation of feeding-deterrent metabolites through bioassay-guided fractionation. This feeding bioassay has advanced our understanding of the factors that control the distribution and abundance of marine invertebrates on Caribbean coral reefs and may inform investigations in diverse fields of inquiry, including pharmacology, biotechnology, and evolutionary ecology.

Fatty acid composition of muscle and adipose tissues of organic and conventional Blanca Andaluza suckling kids

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F. De la Vega

2013-01-01

Full Text Available Interest in the preservation of autochthonous breeds such as the Blanca Andaluza goat (meat breed, raised under grazing-based management, has recently increased among Spanish farmers. A study of the possibilities of transformation to organic production needs to analyze the quality of their products. The aim of this study was to evaluate the fatty acid (FA composition of muscle and adipose tissues of Blanca Andaluza goat kids under organic and conventional grazing–based management system. Twenty-four twin kids (12 males, 12 females were selected from each system. The FA profile was determined in the longissimus thoracis muscle, kidney and pelvic fat. The percentages of C17:0, C17:1, C20:1, C20:4 n-6, C22:2 and several n-3 FAs were higher in organic meat; C12:0, C18:1 trans-11, CLA and C20:5 n-3 were lower in organic meat. The fat depots from the conventional kids showed lower percentages of C12:0, C14:0, C15:0, C17:0, C17:1, C18:3 n-3 and atherogenicity index, and higher percentage of C18:0. In the pelvic fat, the conventional kids displayed lower percentages of C16:0, C18:2 n-6 cis, PUFA, n-3 and n-6 FAs, and greater percentages of C18:1 n-9 cis and MUFA. The conventional kids displayed a major n6:n3 ratio in the kidney fat. No gender differences were observed. Significant differences were found only in some FA percentages of muscle and adipose tissues of suckling kids raised in organic and conventional livestock production systems, and due to this reason conventional grazing–based management farms could easily be transformed into organic production.

A Tissue Engineered Model of Aging: Interdependence and Cooperative Effects in Failing Tissues.

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Acun, A; Vural, D C; Zorlutuna, P

2017-07-11

Aging remains a fundamental open problem in modern biology. Although there exist a number of theories on aging on the cellular scale, nearly nothing is known about how microscopic failures cascade to macroscopic failures of tissues, organs and ultimately the organism. The goal of this work is to bridge microscopic cell failure to macroscopic manifestations of aging. We use tissue engineered constructs to control the cellular-level damage and cell-cell distance in individual tissues to establish the role of complex interdependence and interactions between cells in aging tissues. We found that while microscopic mechanisms drive aging, the interdependency between cells plays a major role in tissue death, providing evidence on how cellular aging is connected to its higher systemic consequences.

Recent Advances in Bioink Design for 3D Bioprinting of Tissues and Organs.

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Ji, Shen; Guvendiren, Murat

2017-01-01

There is a growing demand for alternative fabrication approaches to develop tissues and organs as conventional techniques are not capable of fabricating constructs with required structural, mechanical, and biological complexity. 3D bioprinting offers great potential to fabricate highly complex constructs with precise control of structure, mechanics, and biological matter [i.e., cells and extracellular matrix (ECM) components]. 3D bioprinting is an additive manufacturing approach that utilizes a "bioink" to fabricate devices and scaffolds in a layer-by-layer manner. 3D bioprinting allows printing of a cell suspension into a tissue construct with or without a scaffold support. The most common bioinks are cell-laden hydrogels, decellulerized ECM-based solutions, and cell suspensions. In this mini review, a brief description and comparison of the bioprinting methods, including extrusion-based, droplet-based, and laser-based bioprinting, with particular focus on bioink design requirements are presented. We also present the current state of the art in bioink design including the challenges and future directions.

Recent Advances in Bioink Design for 3D Bioprinting of Tissues and Organs

Science.gov (United States)

Ji, Shen; Guvendiren, Murat

2017-01-01

There is a growing demand for alternative fabrication approaches to develop tissues and organs as conventional techniques are not capable of fabricating constructs with required structural, mechanical, and biological complexity. 3D bioprinting offers great potential to fabricate highly complex constructs with precise control of structure, mechanics, and biological matter [i.e., cells and extracellular matrix (ECM) components]. 3D bioprinting is an additive manufacturing approach that utilizes a “bioink” to fabricate devices and scaffolds in a layer-by-layer manner. 3D bioprinting allows printing of a cell suspension into a tissue construct with or without a scaffold support. The most common bioinks are cell-laden hydrogels, decellulerized ECM-based solutions, and cell suspensions. In this mini review, a brief description and comparison of the bioprinting methods, including extrusion-based, droplet-based, and laser-based bioprinting, with particular focus on bioink design requirements are presented. We also present the current state of the art in bioink design including the challenges and future directions. PMID:28424770

Challenges and opportunities for tissue-engineering polarized epithelium.

Science.gov (United States)

Paz, Ana C; Soleas, John; Poon, James C H; Trieu, Dennis; Waddell, Thomas K; McGuigan, Alison P

2014-02-01

The epithelium is one of the most important tissue types in the body and the specific organization of the epithelial cells in these tissues is important for achieving appropriate function. Since many tissues contain an epithelial component, engineering functional epithelium and understanding the factors that control epithelial maturation and organization are important for generating whole artificial organ replacements. Furthermore, disruption of the cellular organization leads to tissue malfunction and disease; therefore, engineered epithelium could provide a valuable in vitro model to study disease phenotypes. Despite the importance of epithelial tissues, a surprisingly limited amount of effort has been focused on organizing epithelial cells into artificial polarized epithelium with an appropriate structure that resembles that seen in vivo. In this review, we provide an overview of epithelial tissue organization and highlight the importance of cell polarization to achieve appropriate epithelium function. We next describe the in vitro models that exist to create polarized epithelium and summarize attempts to engineer artificial epithelium for clinical use. Finally, we highlight the opportunities that exist to translate strategies from tissue engineering other tissues to generate polarized epithelium with a functional structure.

Critical Point in Self-Organized Tissue Growth

Science.gov (United States)

Aguilar-Hidalgo, Daniel; Werner, Steffen; Wartlick, Ortrud; González-Gaitán, Marcos; Friedrich, Benjamin M.; Jülicher, Frank

2018-05-01

We present a theory of pattern formation in growing domains inspired by biological examples of tissue development. Gradients of signaling molecules regulate growth, while growth changes these graded chemical patterns by dilution and advection. We identify a critical point of this feedback dynamics, which is characterized by spatially homogeneous growth and proportional scaling of patterns with tissue length. We apply this theory to the biological model system of the developing wing of the fruit fly Drosophila melanogaster and quantitatively identify signatures of the critical point.

Perceptions of the gift relationship in organ and tissue donation: Views of intensivists and donor and recipient coordinators.

Science.gov (United States)

Shaw, Rhonda

2010-02-01

The international literature on organ donation and transplantation has drawn attention to the popularity of "gift of life" discourse among pro-donation advocates, transplantation specialists, and within organisations lobbying for improved donation rates to promote the benefits of organ donation among members of the general public. In Aotearoa/New Zealand, gift of life discourse is robust. Aside from attempts to elicit altruism by promoting tissue donation in the public domain, gift terminology separates the act of donation from that of commerce and the commodification of body tissues. In distancing donation from commodification and the potential to degrade and exploit human beings, it is assumed that gift discourse transmits the positive message that donation is a noble and morally worthy act. Recent sociological research has shown that assumptions of the gift as one-way and altruistic do not necessarily align with people's perceptions and experience of donating body tissues, and that the vocabulary used to describe these acts is often at variance with reality. This article draws on interview data with 15 critical care specialists (intensivists) and donor and recipient coordinators, examining their perceptions of the relevance of gift discourse and its applicability in the context of deceased donation in Aotearoa/New Zealand. The data indicate several problems with gift rhetoric to describe the situations health professionals encounter. In sum, gift terminology tends to downplay the sacrifice involved in tissue donation generally, as well as depoliticising the exchange relations of tissue transfer in contemporary consumer culture and in the global context. This raises questions about the underlying ethics of language choice and what, if anything, empirical accounts of tissue transfer can contribute to ethical debates. Copyright 2009 Elsevier Ltd. All rights reserved.

Organ printing: from bioprinter to organ biofabrication line.

Science.gov (United States)

Mironov, Vladimir; Kasyanov, Vladimir; Markwald, Roger R

2011-10-01

Organ printing, or the layer by layer additive robotic biofabrication of functional three-dimensional tissue and organ constructs using self-assembling tissue spheroid building blocks, is a rapidly emerging technology that promises to transform tissue engineering into a commercially successful biomedical industry. It is increasingly obvious that similar well-established industries implement automated robotic systems on the path to commercial translation and economic success. The use of robotic bioprinters alone however is not sufficient for the development of large industrial scale organ biofabrication. The design and development of a fully integrated organ biofabrication line is imperative for the commercial translation of organ printing technology. This paper presents recent progress and challenges in the development of the essential components of an organ biofabrication line. Copyright © 2011 Elsevier Ltd. All rights reserved.

The Rotator Cuff Organ: Integrating Developmental Biology, Tissue Engineering, and Surgical Considerations to Treat Chronic Massive Rotator Cuff Tears.

Science.gov (United States)

Rothrauff, Benjamin B; Pauyo, Thierry; Debski, Richard E; Rodosky, Mark W; Tuan, Rocky S; Musahl, Volker

2017-08-01

The torn rotator cuff remains a persistent orthopedic challenge, with poor outcomes disproportionately associated with chronic, massive tears. Degenerative changes in the tissues that comprise the rotator cuff organ, including muscle, tendon, and bone, contribute to the poor healing capacity of chronic tears, resulting in poor function and an increased risk for repair failure. Tissue engineering strategies to augment rotator cuff repair have been developed in an effort to improve rotator cuff healing and have focused on three principal aims: (1) immediate mechanical augmentation of the surgical repair, (2) restoration of muscle quality and contractility, and (3) regeneration of native enthesis structure. Work in these areas will be reviewed in sequence, highlighting the relevant pathophysiology, developmental biology, and biomechanics, which must be considered when designing therapeutic applications. While the independent use of these strategies has shown promise, synergistic benefits may emerge from their combined application given the interdependence of the tissues that constitute the rotator cuff organ. Furthermore, controlled mobilization of augmented rotator cuff repairs during postoperative rehabilitation may provide mechanotransductive cues capable of guiding tissue regeneration and restoration of rotator cuff function. Present challenges and future possibilities will be identified, which if realized, may provide solutions to the vexing condition of chronic massive rotator cuff tears.

Autoradiographic demonstration of unscheduled DNA synthesis in oral tissues treated with chemical carcinogens in short-term organ culture

International Nuclear Information System (INIS)

Ide, F.; Umemura, S.; Ishikawa, T.; Takayama, S.

1981-01-01

A system in which oral tissues of inbred F344 adult rats and Syrian golden hamster embryos were used in combination with autoradiography was developed for measurement of unscheduled DNA synthesis (UDS). For this, oral mucosa, submandibular gland, tooth germ and mandible in short-term organ cultures were treated with 4-nitroquinoline l-oxide or N-methyl-N-nitrosourea plus (methyl- 3 H)thymidine. Significant numbers of silver grains, indicating UDS, were detected over the nuclei of cells of all these tissues except rat salivary gland after treatment with carcinogens. This autoradiographic method is suitable for detection of UDS in oral tissues in conditions mimicking those in vivo. Results obtained in this study indicated a potential use of this system for studies on the mechanism of carcinogenesis at a cellular level comparable to in vivo carcinogenesis studies on oral tissues. (author)

Dosimetry of {sup 223}Ra-chloride: dose to normal organs and tissues

Energy Technology Data Exchange (ETDEWEB)

Lassmann, Michael [University of Wuerzburg, Department of Nuclear Medicine, Wuerzburg (Germany); Nosske, Dietmar [Federal Office for Radiation Protection (BfS), Department of Radiation and Health, Oberschleissheim (Germany)

2013-02-15

{sup 223}Ra-Chloride (also called Alpharadin {sup registered}) targets bone metastases with short range alpha particles. In recent years several clinical trials have been carried out showing, in particular, the safety and efficacy of palliation of painful bone metastases in patients with castration-resistant prostate cancer using {sup 223}Ra-chloride. The purpose of this work was to provide a comprehensive dosimetric calculation of organ doses after intravenous administration of {sup 223}Ra-chloride according to the present International Commission on Radiological Protection (ICRP) model for radium. Absorbed doses were calculated for 25 organs or tissues. Bone endosteum and red bone marrow show the highest dose coefficients followed by liver, colon and intestines. After a treatment schedule of six intravenous injections with 0.05 MBq/kg of {sup 223}Ra-chloride each, corresponding to 21 MBq for a 70 kg patient, the absorbed alpha dose to the bone endosteal cells is about 16 Gy and the corresponding absorbed dose to the red bone marrow is approximately 1.5 Gy. The comprehensive list of dose coefficients presented in this work will assist in comparing and evaluating organ doses from various therapy modalities used in nuclear medicine and will provide a base for further development of patient-specific dosimetry. (orig.)

LDR brachytherapy: can low dose rate hypersensitivity from the "inverse" dose rate effect cause excessive cell killing to peripherial connective tissues and organs?

Science.gov (United States)

Leonard, B E; Lucas, A C

2009-02-01

Examined here are the possible effects of the "inverse" dose rate effect (IDRE) on low dose rate (LDR) brachytherapy. The hyper-radiosensitivity and induced radioresistance (HRS/IRR) effect benefits cell killing in radiotherapy, and IDRE and HRS/IRR seem to be generated from the same radioprotective mechanisms. We have computed the IDRE excess cell killing experienced in LDR brachytherapy using permanent seed implants. We conclude, firstly, that IDRE is a dose rate-dependent manifestation of HRS/IRR. Secondly, the presence of HRS/IRR or IDRE in a cell species or tissue must be determined by direct dose-response measurements. Thirdly, a reasonable estimate is that 50-80% of human adjoining connective and organ tissues experience IDRE from permanent implanted LDR brachytherapy. If IDRE occurs for tissues at point A for cervical cancer, the excess cell killing will be about a factor of 3.5-4.0 if the initial dose rate is 50-70 cGy h(-1). It is greater for adjacent tissues at lower dose rates and higher for lower initial dose rates at point A. Finally, higher post-treatment complications are observed in LDR brachytherapy, often for unknown reasons. Some of these are probably a result of IDRE excess cell killing. Measurements of IDRE need be performed for connective and adjacent organ tissues, i.e. bladder, rectum, urinary tract and small bowels. The measured dose rate-dependent dose responses should extended to tissues and organs remain above IDRE thresholds).

Plant Tissue Culture

Indian Academy of Sciences (India)

Admin

Plant tissue culture is a technique of culturing plant cells, tissues and organs on ... working methods (Box 2) and discovery of the need for B vita- mins and auxins for ... Kotte (Germany) reported some success with growing isolated root tips.

Structural and Functional Components of the Skate Sensory Organ Ampullae of Lorenzini.

Science.gov (United States)

Zhang, Xing; Xia, Ke; Lin, Lei; Zhang, Fuming; Yu, Yanlei; St Ange, Kalib; Han, Xiaorui; Edsinger, Eric; Sohn, Joel; Linhardt, Robert J

2018-05-09

The skate, a cartilaginous fish related to sharks and rays, possesses a unique electrosensitive sensory organ known as the ampullae of Lorenzini (AoL). This organ is responsible for the detection of weak electric field changes caused by the muscle contractions of their prey. While keratan sulfate (KS) is believed to be a component of a jelly that fills this sensory organ and has been credited with its high proton conductivity, modern analytical methods have not been applied to its characterization. Surprisingly, total glycosaminoglycan (GAG) analysis demonstrates that the KS from skate jelly is extraordinarily pure, containing no other GAGs. This KS had a molecular weight of 20 to 30 kDa, consisting primarily of N-linked KS comprised mostly of a monosulfated disaccharide repeating unit, →3) Gal (1→4) GlcNAc6S (1→. Proteomic analysis of AoL jelly suggests that transferrin, keratin, and mucin serve as KS core proteins. Actin and tropomyosin are responsible for assembling the macrostructure of the jelly, and parvalbumin α-like protein and calreticulin regulate calcium and potassium channels involved in the transduction of the electrical signal, once conducted down the AoL by the jelly, serving as the molecular basis for electroreception.

[Connective tissue and inflammation].

Science.gov (United States)

Jakab, Lajos

2014-03-23

The author summarizes the structure of the connective tissues, the increasing motion of the constituents, which determine the role in establishing the structure and function of that. The structure and function of the connective tissue are related to each other in the resting as well as inflammatory states. It is emphasized that cellular events in the connective tissue are part of the defence of the organism, the localisation of the damage and, if possible, the maintenance of restitutio ad integrum. The organism responds to damage with inflammation, the non specific immune response, as well as specific, adaptive immunity. These processes are located in the connective tissue. Sterile and pathogenic inflammation are relatively similar processes, but inevitable differences are present, too. Sialic acids and glycoproteins containing sialic acids have important roles, and the role of Siglecs is also highlighted. Also, similarities and differences in damages caused by pathogens and sterile agents are briefly summarized. In addition, the roles of adhesion molecules linked to each other, and the whole event of inflammatory processes are presented. When considering practical consequences it is stressed that the structure (building up) of the organism and the defending function of inflammation both have fundamental importance. Inflammation has a crucial role in maintaining the integrity and the unimpaired somato-psychological state of the organism. Thus, inflammation serves as a tool of organism identical with the natural immune response, inseparably connected with the specific, adaptive immune response. The main events of the inflammatory processes take place in the connective tissue.

[Strategies to choose scaffold materials for tissue engineering].

Science.gov (United States)

Gao, Qingdong; Zhu, Xulong; Xiang, Junxi; Lü, Yi; Li, Jianhui

2016-02-01

Current therapies of organ failure or a wide range of tissue defect are often not ideal. Transplantation is the only effective way for long time survival. But it is hard to meet huge patients demands because of donor shortage, immune rejection and other problems. Tissue engineering could be a potential option. Choosing a suitable scaffold material is an essential part of it. According to different sources, tissue engineering scaffold materials could be divided into three types which are natural and its modified materials, artificial and composite ones. The purpose of tissue engineering scaffold is to repair the tissues or organs damage, so could reach the ideal recovery in its function and structure aspect. Therefore, tissue engineering scaffold should even be as close as much to the original tissue or organs in function and structure. We call it "organic scaffold" and this strategy might be the drastic perfect substitute for the tissues or organs in concern. Optimized organization with each kind scaffold materials could make up for biomimetic structure and function of the tissue or organs. Scaffold material surface modification, optimized preparation procedure and cytosine sustained-release microsphere addition should be considered together. This strategy is expected to open new perspectives for tissue engineering. Multidisciplinary approach including material science, molecular biology, and engineering might find the most ideal tissue engineering scaffold. Using the strategy of drawing on each other strength and optimized organization with each kind scaffold material to prepare a multifunctional biomimetic tissue engineering scaffold might be a good method for choosing tissue engineering scaffold materials. Our research group had differentiated bone marrow mesenchymal stem cells into bile canaliculi like cells. We prepared poly(L-lactic acid)/poly(ε-caprolactone) biliary stent. The scaffold's internal played a part in the long-term release of cytokines which

Translational research: cells, tissues and organisms

International Nuclear Information System (INIS)

Chang, P.Y.

2003-01-01

Exposure to the complex space radiation environment poses an important health hazard for astronauts in long-term space missions. The central theme of NASA's space radiation health research effort is to acquire scientific knowledge to understand the mechanisms of particle radiation effects in biological systems and to use this knowledge to set exposure limits and to design countermeasures that will protect the astronauts. During the past few decades, a rich body of data has been developed to characterize HZE-induced biological responses both in vitro and in vivo using ground-based accelerator facilities available in a number of facilities around the world. Although much is known about particle-radiation-induced DNA damage and cell killing in cultured cell lines, recent evidence suggest that numerous other factors, such as membrane effects, altered gene expression, bystander effects and specific cell-type dependent features also play critical roles in cellular responses. Dose- and particle-dependent studies are also available for multicellular tissues and animal model systems where emerging information demonstrates complex interactions between cells including intercellular communications, activation of proteins, alterations in the microenvironment, tissue-specificity, and genetic status and these contribute in determining the consequences of HZE radiation. Due to the lack of human data, risk estimates depend on the extrapolation of experimental results in animals and cultured cell systems to man. In this presentation, selected topics reviewing particle radiation effects in cells, tissues and animal will be used to illustrate the importance of translational research and some of the limitations of such approaches

In-house coordination project for organ and tissue procurement: social responsibility and promising results.

Science.gov (United States)

Silva, Vanessa Silva E; Moura, Luciana Carvalho; Martins, Luciana Ribeiro; Santos, Roberta Cristina Cardoso Dos; Schirmer, Janine; Roza, Bartira de Aguiar

2016-01-01

to report the results of evaluation regarding changes in the number of potential donor referrals, actual donors, and conversion rates after the implementation of an in-house organ and tissue donation for transplantation coordination project. epidemiological study, both retrospective and transversal, was performed with organ donation data from the Secretariat of Health for the State and the in-house organ donation coordination project of a beneficent hospital. The data was compared using nonparametric statistical Mann-Whitney test, and the Student's t-test, considering a significance level of 5% (p <0.05). there were statistically significant differences (p < 0.05), before and after the implementation of the project on the number of potential donor notification/month (3.05 - 4.7 ), number of actual donor/month (0.78 to 1.60) and rate of conversion ( 24.7 to 34.8 %). The hospitals 1, 2, 7 and 8 had significant results in potential donor, actual donor or conversion rate. the presence of an in-house coordinator is promising and beneficial, the specialist is important to change the indicators of efficiency, which consequently reduces the waiting lists for organ transplants.

Spatial organization and correlation properties quantify structural changes on mesoscale of parenchymatous plant tissue

Energy Technology Data Exchange (ETDEWEB)

Valous, N. A.; Delgado, A.; Sun, D.-W., E-mail: dawen.sun@ucd.ie [School of Biosystems Engineering, University College Dublin, National University of Ireland, Belfield, Dublin 4, Dublin (Ireland); Drakakis, K. [Complex and Adaptive Systems Laboratory, University College Dublin, National University of Ireland, Belfield, Dublin 4, Dublin (Ireland)

2014-02-14

The study of plant tissue parenchyma's intercellular air spaces contributes to the understanding of anatomy and physiology. This is challenging due to difficulty in making direct measurements of the pore space and the complex mosaic of parenchymatous tissue. The architectural complexity of pore space has shown that single geometrical measurements are not sufficient for characterization. The inhomogeneity of distribution depends not only on the percentage content of phase, but also on how the phase fills the space. The lacunarity morphometric, as multiscale measure, provides information about the distribution of gaps that correspond to degree of spatial organization in parenchyma. Additionally, modern theories have suggested strategies, where the focus has shifted from the study of averages and histograms to the study of patterns in data fluctuations. Detrended fluctuation analysis provides information on the correlation properties of the parenchyma at different spatial scales. The aim is to quantify (with the aid of the aforementioned metrics), the mesostructural changes—that occur from one cycle of freezing and thawing—in the void phase of pome fruit parenchymatous tissue, acquired with X-ray microcomputed tomography. Complex systems methods provide numerical indices and detailed insights regarding the freezing-induced modifications upon the arrangement of cells and voids. These structural changes have the potential to lead to physiological disorders. The work can further stimulate interest for the analysis of internal plant tissue structures coupled with other physico-chemical processes or phenomena.

Spatial organization and correlation properties quantify structural changes on mesoscale of parenchymatous plant tissue

International Nuclear Information System (INIS)

Valous, N. A.; Delgado, A.; Sun, D.-W.; Drakakis, K.

2014-01-01

The study of plant tissue parenchyma's intercellular air spaces contributes to the understanding of anatomy and physiology. This is challenging due to difficulty in making direct measurements of the pore space and the complex mosaic of parenchymatous tissue. The architectural complexity of pore space has shown that single geometrical measurements are not sufficient for characterization. The inhomogeneity of distribution depends not only on the percentage content of phase, but also on how the phase fills the space. The lacunarity morphometric, as multiscale measure, provides information about the distribution of gaps that correspond to degree of spatial organization in parenchyma. Additionally, modern theories have suggested strategies, where the focus has shifted from the study of averages and histograms to the study of patterns in data fluctuations. Detrended fluctuation analysis provides information on the correlation properties of the parenchyma at different spatial scales. The aim is to quantify (with the aid of the aforementioned metrics), the mesostructural changes—that occur from one cycle of freezing and thawing—in the void phase of pome fruit parenchymatous tissue, acquired with X-ray microcomputed tomography. Complex systems methods provide numerical indices and detailed insights regarding the freezing-induced modifications upon the arrangement of cells and voids. These structural changes have the potential to lead to physiological disorders. The work can further stimulate interest for the analysis of internal plant tissue structures coupled with other physico-chemical processes or phenomena

Development on traceability based on changes of stable isotopes in animal tissues and organs

International Nuclear Information System (INIS)

Cai Xianfeng; Guo Boli; Wei Yimin; Sun Shumin; Wei Shuai

2011-01-01

Stable isotope analysis is a new method in food traceability, which can be used to trace animals' geographical origin and life history. This paper reviews the recent progress of researches on characteristics of stable isotopes and turnover time in different animal tissues and organs, as well as their influence caused by feed, drinking water, geographical origin, storing and processing. The aim of this paper is to provide theoretical reference for studies on the traceability of animal derived food and animals' life history. (authors)

The Contribution of Tissue Level Organization to Genomic Stability Following Low Dose/Low Dose Rate Gamma and Proton Irradiation

Energy Technology Data Exchange (ETDEWEB)

Cheryl G. Burrell, Ph.D.

2012-05-14

The formation of functional tissue units is necessary in maintaining homeostasis within living systems, with individual cells contributing to these functional units through their three-dimensional organization with integrin and adhesion proteins to form a complex extra-cellular matrix (ECM). This is of particular importance in those tissues susceptible to radiation-induced tumor formation, such as epithelial glands. The assembly of epithelial cells of the thyroid is critical to their normal receipt of, and response to, incoming signals. Traditional tissue culture and live animals present significant challenges to radiation exposure and continuous sampling, however, the production of bioreactor-engineered tissues aims to bridge this gap by improve capabilities in continuous sampling from the same functional tissue, thereby increasing the ability to extrapolate changes induced by radiation to animals and humans in vivo. Our study proposes that the level of tissue organization will affect the induction and persistence of low dose radiation-induced genomic instability. Rat thyroid cells, grown in vitro as 3D tissue analogs in bioreactors and as 2D flask grown cultures were exposed to acute low dose (1, 5, 10 and 200 cGy) gamma rays. To assess immediate (6 hours) and delayed (up to 30 days) responses post-irradiation, various biological endpoints were studied including cytogenetic analyses, apoptosis analysis and cell viability/cytotoxicity analyses. Data assessing caspase 3/7 activity levels show that, this activity varies with time post radiation and that, overall, 3D cultures display more genomic instability (as shown by the lower levels of apoptosis over time) when compared to the 2D cultures. Variation in cell viability levels were only observed at the intermediate and late time points post radiation. Extensive analysis of chromosomal aberrations will give further insight on the whether the level of tissue organization influences genomic instability patterns after

Children as donors : a national study to assess procurement of organs and tissues in pediatric intensive care units

NARCIS (Netherlands)

Siebelink, Marion J.; Albers, Marcel J. I. J.; Roodbol, Petrie F.; Van de Wiel, Harry B. M.

2012-01-01

A shortage of size-matched organs and tissues is the key factor limiting transplantation in children. Empirical data on procurement from pediatric donors is sparse. This study investigated donor identification, parental consent, and effectuation rates, as well as adherence to the national protocol.

Succession after fire: variation in \\delta13C of organic tissues and respired CO2 in boreal forests

Science.gov (United States)

Fessenden, J. E.; Li, H.; Mack, M.; Schuur, T.; Warren, S.; Randerson, J. T.

2001-12-01

Isotope ratios of carbon dioxide and leaf organic matter were measured in 5 neighboring forests of varying ages: 7, 14, 45, 140, and 160 years. These forests are composed primarily of black spruce (Picea Mariana) and quaking aspen (Populus tremuloides) with a shift in species dominance from aspen to spruce 50 years after fire disturbance. Research on the carbon isotope ratios of leaf material and CO2 was conducted to look for influences from species composition, forest age, and time after most recent burn. Samples of organic \\delta13C in whole leaf tissue were collected from the dominant species of each forest. Concurrent aboveground NPP measurements allowed us to estimate total ecosystem \\delta13C by providing a method for weighting \\delta13C of individual species and plant tissues. \\delta13CO2 and [CO2] were measured on canopy CO2 to determine the isotopic ratio of ecosystem respiration. The atmospheric results indicated that the \\delta13C of ecosystem respiration changes with successional stage. Specifically, the aspen dominating forests showed 13C depleted values relative to the spruce dominated forests. Organic results showed more 13C-enriched values with increased forest age and vegetation functional type. Specifically, oldest trees within the coniferous species had the most 13C-enriched values in leaf tissues. These results suggest that increases in the disturbance regime of northern boreal forests will lead to a decrease in the \\delta13C of ecosystem carbon with consequences for the atmospheric \\delta13C budget.

A bio-inspired, microchanneled hydrogel with controlled spacing of cell adhesion ligands regulates 3D spatial organization of cells and tissue.

Science.gov (United States)

Lee, Min Kyung; Rich, Max H; Lee, Jonghwi; Kong, Hyunjoon

2015-07-01

Bioactive hydrogels have been extensively studied as a platform for 3D cell culture and tissue regeneration. One of the key desired design parameters is the ability to control spatial organization of biomolecules and cells and subsequent tissue in a 3D matrix. To this end, this study presents a simple but advanced method to spatially organize microchanneled, cell adherent gel blocks and non-adherent ones in a single construct. This hydrogel system was prepared by first fabricating a bimodal hydrogel in which the microscale, alginate gel blocks modified with cell adhesion peptides containing Arg-Gly-Asp sequence (RGD peptides), and those free of RGD peptides, were alternatingly presented. Then, anisotropically aligned microchannels were introduced by uniaxial freeze-drying of the bimodal hydrogel. The resulting gel system could drive bone marrow stromal cells to adhere to and differentiate into neuron and glial cells exclusively in microchannels of the alginate gel blocks modified with RGD peptides. Separately, the bimodal gel loaded with microparticles releasing vascular endothelial growth factor stimulated vascular growth solely into microchannels of the RGD-alginate gel blocks in vivo. These results were not attained by the bimodal hydrogel fabricated to present randomly oriented micropores. Overall, the bimodal gel system could regulate spatial organization of nerve-like tissue or blood vessels at sub-micrometer length scale. We believe that the hydrogel assembly demonstrated in this study will be highly useful in developing a better understanding of diverse cellular behaviors in 3D tissue and further improve quality of a wide array of engineered tissues. Copyright © 2015 Elsevier Ltd. All rights reserved.

Application of polarization OCT in tissue engineering

Science.gov (United States)

Yang, Ying; Ahearne, Mark; Bagnaninchi, Pierre O.; Hu, Bin; Hampson, Karen; El Haj, Alicia J.

2008-02-01

For tissue engineering of load-bearing tissues, such as bone, tendon, cartilage, and cornea, it is critical to generate a highly organized extracellular matrix. The major component of the matrix in these tissues is collagen, which usually forms a highly hierarchical structure with increasing scale from fibril to fiber bundles. These bundles are ordered into a 3D network to withstand forces such as tensile, compressive or shear. To induce the formation of organized matrix and create a mimic body environment for tissue engineering, in particular, tendon tissue engineering, we have fabricated scaffolds with features to support the formation of uniaxially orientated collagen bundles. In addition, mechanical stimuli were applied to stimulate tissue formation and matrix organization. In parallel, we seek a nondestructive tool to monitor the changes within the constructs in response to these external stimulations. Polarizationsensitive optical coherence tomography (PSOCT) is a non-destructive technique that provides functional imaging, and possesses the ability to assess in depth the organization of tissue. In this way, an engineered tissue construct can be monitored on-line, and correlated with the application of different stimuli by PSOCT. We have constructed a PSOCT using a superluminescent diode (FWHM 52nm) in this study and produced two types of tendon constructs. The matrix structural evolution under different mechanical stimulation has been evaluated by the PSOCT. The results in this study demonstrate that PSOCT was a powerful tool enabling us to monitor non-destructively and real time the progressive changes in matrix organization and assess the impact of various stimuli on tissue orientation and growth.

Synthetic biology meets tissue engineering.

Science.gov (United States)

Davies, Jamie A; Cachat, Elise

2016-06-15

Classical tissue engineering is aimed mainly at producing anatomically and physiologically realistic replacements for normal human tissues. It is done either by encouraging cellular colonization of manufactured matrices or cellular recolonization of decellularized natural extracellular matrices from donor organs, or by allowing cells to self-organize into organs as they do during fetal life. For repair of normal bodies, this will be adequate but there are reasons for making unusual, non-evolved tissues (repair of unusual bodies, interface to electromechanical prostheses, incorporating living cells into life-support machines). Synthetic biology is aimed mainly at engineering cells so that they can perform custom functions: applying synthetic biological approaches to tissue engineering may be one way of engineering custom structures. In this article, we outline the 'embryological cycle' of patterning, differentiation and morphogenesis and review progress that has been made in constructing synthetic biological systems to reproduce these processes in new ways. The state-of-the-art remains a long way from making truly synthetic tissues, but there are now at least foundations for future work. © 2016 Authors; published by Portland Press Limited.

Effects of Tissue Culture and Mycorrhiza Applications in Organic Farming on Concentrations of Phytochemicals and Antioxidant Capacities in Ginger (Zingiber officinale Roscoe) Rhizomes and Leaves.

Science.gov (United States)

Min, Byungrok R; Marsh, Lurline E; Brathwaite, Keegan; Daramola, Adebola O

2017-04-01

Tissue culture and mycorrhiza applications can provide disease-free seedlings and enhanced nutrient absorption, respectively, for organic farming. Ginger (Zingiber officinale Roscoe) is rich in phytochemicals and has various health-protective potentials. This study was aimed at determining effects of tissue culture and mycorrhiza applications alone or in combinations in organic farming on phytochemical contents (total phenolics and flavonoids [TP and TF, respectively], gingerol and shogaol homologues, phenolic acids, and carotenoids) and antioxidant capacities (DPPH [2,2-diphenyl-1-picrylhydrazyl] radical scavenging, oxygen radical absorbance (ORAC), and iron-chelating capacities [ICC]) in solvent-extractable (Free) and cell-wall-matrix-bound (Bound) fractions of ginger rhizome and Free fraction of the leaves in comparison with non-organics. Concentrations of the phytochemicals and antioxidant capacities, except for carotenoids and ICC, were significantly higher in organic ginger rhizomes and leaves than in non-organics regardless of the fractions and treatments (P < 0.05). Mycorrhiza application in organic farming significantly increased levels of TP, TF, gingerols, and ORAC in the Free fraction of the rhizome (P < 0.05). Furthermore, the combined application of tissue culture and mycorrhiza significantly increased concentrations of TF and gingerols and ORAC in the Free fraction of the rhizome (P < 0.05), suggesting their synergistic effects. Considerable amounts of phenolics were found in the Bound fractions of the rhizomes. Six-gingerol, ferulic acid, and lutein were predominant ones among gingerols, phenolic acids, and carotenoids, respectively, in ginger rhizomes. The results suggest that organic farming with mycorrhiza and tissue culture applications can increase concentrations of phytochemicals and antioxidant capacities in ginger rhizomes and leaves and therefore improve their health-protective potentials. © 2017 Institute of Food Technologists®.

Tissue-Mimicking Geometrical Constraints Stimulate Tissue-Like Constitution and Activity of Mouse Neonatal and Human-Induced Pluripotent Stem Cell-Derived Cardiac Myocytes

Directory of Open Access Journals (Sweden)

Götz Pilarczyk

2016-01-01

Full Text Available The present work addresses the question of to what extent a geometrical support acts as a physiological determining template in the setup of artificial cardiac tissue. Surface patterns with alternating concave to convex transitions of cell size dimensions were used to organize and orientate human-induced pluripotent stem cell (hIPSC-derived cardiac myocytes and mouse neonatal cardiac myocytes. The shape of the cells, as well as the organization of the contractile apparatus recapitulates the anisotropic line pattern geometry being derived from tissue geometry motives. The intracellular organization of the contractile apparatus and the cell coupling via gap junctions of cell assemblies growing in a random or organized pattern were examined. Cell spatial and temporal coordinated excitation and contraction has been compared on plain and patterned substrates. While the α-actinin cytoskeletal organization is comparable to terminally-developed native ventricular tissue, connexin-43 expression does not recapitulate gap junction distribution of heart muscle tissue. However, coordinated contractions could be observed. The results of tissue-like cell ensemble organization open new insights into geometry-dependent cell organization, the cultivation of artificial heart tissue from stem cells and the anisotropy-dependent activity of therapeutic compounds.

Tissue Engineering Organs for Space Biology Research

Science.gov (United States)

Vandenburgh, H. H.; Shansky, J.; DelTatto, M.; Lee, P.; Meir, J.

1999-01-01

Long-term manned space flight requires a better understanding of skeletal muscle atrophy resulting from microgravity. Atrophy most likely results from changes at both the systemic level (e.g. decreased circulating growth hormone, increased circulating glucocorticoids) and locally (e.g. decreased myofiber resting tension). Differentiated skeletal myofibers in tissue culture have provided a model system over the last decade for gaining a better understanding of the interactions of exogenous growth factors, endogenous growth factors, and muscle fiber tension in regulating protein turnover rates and muscle cell growth. Tissue engineering these cells into three dimensional bioartificial muscle (BAM) constructs has allowed us to extend their use to Space flight studies for the potential future development of countermeasures.

Evaluation of Two Enzyme-Linked Immunosorbent Assay Kits for Chikungunya Virus IgM Using Samples from Deceased Organ and Tissue Donors

Science.gov (United States)

Altrich, Michelle L.; Nowicki, Marek J.

2016-01-01

The identification of nearly 3,500 cases of chikungunya virus (CHIKV) infection in U.S. residents returning in 2014 and 2015 from areas in which it is endemic has raised concerns within the transplant community that, should recently infected individuals become organ and/or tissue donors, CHIKV would be transmitted to transplant recipients. Thus, tests designed to detect recent CHIKV infection among U.S. organ and tissue donors may become necessary in the future. Accordingly, we evaluated 2 enzyme-linked immunosorbent assays (ELISAs) for CHIKV IgM readily available in the United States using 1,000 deidentified serum or plasma specimens collected from donors between November 2014 and March 2015. The Euroimmun indirect ELISA identified 38 reactive specimens; however, all 38 were negative for CHIKV IgG and IgM in immunofluorescence assays (IFAs) conducted at a reference laboratory and, thus, were falsely reactive in the Euroimmun CHIKV IgM assay. The InBios IgM-capture ELISA identified 26 reactive samples, and one was still reactive (index ≥ 1.00) when retested using the InBios kit with a background subtraction modification to identify false reactivity. This reactive specimen was CHIKV IgM negative but IgG positive by IFAs at two reference laboratories; plaque reduction neutralization testing (PRNT) demonstrated CHIKV-specific reactivity. The IgG and PRNT findings strongly suggest that the InBios CHIKV IgM-reactive result represents true reactivity, even though the IgM IFA result was negative. If testing organ/tissue donors for CHIKV IgM becomes necessary, the limitations of the currently available CHIKV IgM ELISAs and options for their optimization must be understood to avoid organ/tissue wastage due to falsely reactive results. PMID:27535838

Cross-Tissue Transcriptomic Analysis of Human Secondary Lymphoid Organ-Residing ILC3s Reveals a Quiescent State in the Absence of Inflammation

Directory of Open Access Journals (Sweden)

Yotam E. Bar-Ephraim

2017-10-01

Full Text Available A substantial number of human and mouse group 3 innate lymphoid cells (ILC3s reside in secondary lymphoid organs, yet the phenotype and function of these ILC3s is incompletely understood. Here, we employed an unbiased cross-tissue transcriptomic approach to compare human ILC3s from non-inflamed lymph nodes and spleen to their phenotypic counterparts in inflamed tonsils and from circulation. These analyses revealed that, in the absence of inflammation, lymphoid organ-residing ILC3s lack transcription of cytokines associated with classical ILC3 functions. This was independent of expression of the natural cytotoxicity receptor NKp44. However, and in contrast to ILC3s from peripheral blood, lymphoid organ-residing ILC3s express activating cytokine receptors and have acquired the ability to be recruited into immune responses by inflammatory cytokines. This comprehensive cross-tissue dataset will allow for identification of functional changes in human lymphoid organ ILC3s associated with human disease.

A simple calculation for the determination of organ or tissue dose from medical x-ray diagnosis for stomach and chest

International Nuclear Information System (INIS)

Nishizawa, Kanae

1984-01-01

A simple calculation method has been developed to determine the organ or tissue doses of patients for typical X-ray diagnoses. The absorbed doses related to radiation-induced stochastic effects were calculated based on the dosimetric parameters experimentally determined and technical parameters for X-ray diagnostic examinations. The present method is principally based on the TRA method for the beam therapy. The dosimetric parameters such as percentage depth-dose curves and isodose curves were measured with ionization chambers in the MixDP phantom. The distance from the incident surface of X-ray beams to the organ or tissue of interest was determined with a mathematical phantom, which was the modified version of the MIRD phantom for the average Japanese adult. The absorbed doses were determined with a simple table look-up method using a computer. The calculated doses were tabulated for various technical parameters of stomach and chest X-ray examinations. The present calculation was applied to the Rando woman phantom to compare with the phantom measurements. The calculated values agree with the experimental doses within 20% discrepancy. It was concluded that the present calculation method can determine organ or tissue doses very simply for various X-ray examinations and that it was valuable for the estimation of population doses and risks from X-ray diagnoses. (author)

Compined preoperative diagnosis of stomach cancer involvement of the abdominal and retroperitoneal organs and tissues

International Nuclear Information System (INIS)

Fisher, M.E.; Gabuniya, R.I.; Kolesnikova, E.K.; Bal'ter, S.A.; Ostrovtsev, I.V.; Dolgushin, B.I.; Mazurov, S.T.; Mironova, G.T.

1987-01-01

An analysis of 136 cases of stomach cancer led to the determination of the role and place of gammatopography, echography, computerized X-ray tomography, angiography and laparoscopy in specified preoperative diagnosis of extraorganic spreading of primary tumors. The informative value and shortcomings of certain methods were shown. A high accuracy of the entire set of diagnostic procedures (94.8%) in the preoperative definition of stomach cancer involvement of the abdominal and retroperitoneal organs and tissues was emphasized

Downregulation of tropomyosin-1 in squamous cell carcinoma of esophagus, the role of Ras signaling and methylation.

Science.gov (United States)

Zare, Maryam; Jazii, Ferdous Rastgar; Soheili, Zahra-Soheila; Moghanibashi, Mohamad-Mehdi

2012-10-01

Tropomyosins (TMs) are a family of cytoskeletal proteins that bind to and stabilize actin microfilaments. Non-muscle cells express multiple isoforms of TMs including three high molecular weight (HMW) isoforms: TM1, TM2, and TM3. While reports have indicated downregulation of TMs in transformed cells and several human cancers, nevertheless, little is known about the underlying mechanism of TMs suppression. In present study the expression of HMW TMs was investigated in squamous cell carcinoma of esophagus (SCCE), relative to primary cell cultures of normal esophagus by western blotting and real-time RT-PCR. Our results showed that TM1, TM2, and TM3 were significantly downregulated in cell line of SCCE. Moreover, mRNA level of TPM1 and TPM2 were markedly decreased by 93% and 96%, in tumor cell line relative to esophagus normal epithelial cells. Therefore, downregulation of TMs could play an important role in tumorigenesis of esophageal cancer. To asses the mechanism of TM downregulation in esophageal cancer, the role of Ras dependent signaling and promoter hypermethylation were investigated. We found that inhibition of two Ras effectory downstream pathways; MEK/ERK and PI3K/Akt leads to significant increased expression of TM1 protein and both TPM1 and TPM2 mRNAs. In addition, methyltransferase inhibition significantly upregulated TM1, suggesting the prominent contribution of promoter hypermethylation in TM1 downregulation in esophageal cancer. These data indicate that downregulation of HMW TMs occurs basically in SCCE and the activation of MEK/ERK and PI3K/Akt pathways as well as the epigenetic mechanism of promoter hypermethylation play important role in TM1 suppression in SCCE. Copyright © 2011 Wiley Periodicals, Inc.

Tissue Engineering: Toward a New Era of Medicine.

Science.gov (United States)

Shafiee, Ashkan; Atala, Anthony

2017-01-14

The goal of tissue engineering is to mitigate the critical shortage of donor organs via in vitro fabrication of functional biological structures. Tissue engineering is one of the most prominent examples of interdisciplinary fields, where scientists with different backgrounds work together to boost the quality of life by addressing critical health issues. Many different fields, such as developmental and molecular biology, as well as technologies, such as micro- and nanotechnologies and additive manufacturing, have been integral for advancing the field of tissue engineering. Over the past 20 years, spectacular advancements have been achieved to harness nature's ability to cure diseased tissues and organs. Patients have received laboratory-grown tissues and organs made out of their own cells, thus eliminating the risk of rejection. However, challenges remain when addressing more complex solid organs such as the heart, liver, and kidney. Herein, we review recent accomplishments as well as challenges that must be addressed in the field of tissue engineering and provide a perspective regarding strategies in further development.

Tissue Engineering: Current Strategies and Future Directions

OpenAIRE

Olson, Jennifer L.; Atala, Anthony; Yoo, James J.

2011-01-01

Novel therapies resulting from regenerative medicine and tissue engineering technology may offer new hope for patients with injuries, end-stage organ failure, or other clinical issues. Currently, patients with diseased and injured organs are often treated with transplanted organs. However, there is a shortage of donor organs that is worsening yearly as the population ages and as the number of new cases of organ failure increases. Scientists in the field of regenerative medicine and tissue eng...

Organ and Tissue-specific Sucrose Transporters. Important Hubs in Gene and Metabolite Networks Regulating Carbon Use in Wood-forming Tissues of Populus

Energy Technology Data Exchange (ETDEWEB)

Harding, Scott A. [Univ. of Georgia, Athens, GA (United States); Tsai, Chung-Jui [Univ. of Georgia, Athens, GA (United States)

2016-01-04

The overall project objective was to probe the relationship between sucrose transporters and plant productivity in the biomass for biofuels woody perennial, Populus. At the time the proposal was written, sucrose transporters had already been investigated in many plant model systems, primarily with respect to the export of photosynthate sucrose from source leaves, and the uptake of sucrose in storage organs and seeds. Preliminary findings by the PI found that in Populus, sucrose transporter genes (SUTs) were well expressed in wood-forming tissues that comprise the feedstock for biofuels production. Because sucrose comprises by far the predominant form in which photosynthate is delivered from source organs to sink organs like roots and wood-forming tissues, SUTs control a gate that nominally at least could impact the allocation or partitioning of sucrose for potentially competing end uses like growth (stem biomass) and storage. In addition, water use might be conditioned by the way in which sucrose is distributed throughout the plant, and/or by the way in which sucrose is partitioned intracellularly. Several dozen transgenic lines were produced in year 1 of the project to perturb the expression ratio of multiple plasma membrane (PM) SUTs (intercellular trafficking), versus the single tonoplast membrane (TM) sucrose transporter that effectively regulates intracellular trafficking of sucrose. It was possible to obtain transgenic lines with dual SUT gene knockdown using the 35S promoter, but not the wood-specific TUA1 promoter. By the end of project year 2, a decision was made to work with the 35S plants while archiving the TUA1 plants. The PhD candidate charged with producing the transgenic lines abandoned the project during its second year, substantially contributing to the decision to operate with just the 35S lines. That student’s interests ranged more toward evolutionary topics, and a report on SUT gene evolution was published (Peng et al 2014).

Radiopharmaceuticals for localization in target tissues exhibiting a regional pH shift relative to surrounding tissues

International Nuclear Information System (INIS)

Blau, M.; Kung, H.F.

1981-01-01

This patent relates to the preparation and use of radiopharmaceutical chemical compounds comprising a radioactive isotope, other than an isotope of iodine, in chemical combination with at least one primary, secondary or tertiary amino group. The compounds have a lipophilicity sufficiently high at a pH of 7.6 to permit passage of the compound from the blood of a mammal into a target organ or tissue and sufficiently low at a pH of 6.6 to prevent rapid return of the compound from the target organ or tissue to the blood. The compounds have a percent protein binding of less than ninety percent. These compounds may be selectively deposited in at least one target tissue or organ of a mammal, the tissue or organ of which has a significantly different intracellular pH than the blood of the mammal, by introducing the compound of the invention into the bloodstream of the mammal. A plurality of selenide compounds containing Se-75 isotope are claimed in relation to the patent. (U.K.)

Life and Death Decisions: Using School-Based Health Education to Facilitate Family Discussion about Organ and Tissue Donation

Science.gov (United States)

Waldrop, Deborah P.; Tamburlin, Judith A.; Thompson, Sanna J.; Simon, Mark

2004-01-01

Public education that encourages family discussions about organ and tissue donation can enhance understanding, facilitate a donor's wishes and increase the numbers of donations. Action research methods were used to explore the impact of a student-initiated family discussion about donation. Most discussions were positive; only 7% middle school and…

Intermittent straining accelerates the development of tissue properties in engineered heart valve tissue

NARCIS (Netherlands)

Rubbens, M.P.; Mol, A.; Boerboom, R.A.; Bank, R.A.; Baaijens, F.P.T.; Bouten, C.V.C.

2009-01-01

Tissue-engineered heart valves lack sufficient amounts of functionally organized structures and consequently do not meet in vivo mechanical demands. To optimize tissue architecture and hence improve mechanical properties, various in vitro mechanical conditioning protocols have been proposed, of

Accumulation of polonium 210Po in tissues and organs of deer carvidae from Northern Poland.

Science.gov (United States)

Skwarzec, Bogdan; Prucnal, Malgorzata

2007-01-01

This study was undertaken to provide information on accumulation of polonium in tissues and organs of deer carvidae in order to assess the potential transport of this element via food-chain to game meat consumers. Livers, kidneys and muscles of large herbivorous animals belonging to three species: roe deer (Capreolus capreolus), red deer (Cervus elaphus) and fallow deer (Dama dama), collected in Northern Poland, were the subject of the present investigation. Activities of (210)Po were determined by means of alpha spectrometry along with relevant radiochemical procedures. The concentration of (210)Po in analyzed animals decreased in the order kidney > liver > muscle tissue. The average activity concentrations of (210)Po ranged between 0.02 +/- 0.01 Bq. kg(- 1) w.w. in muscles and 7.15 +/- 0.12 Bq. kg(- 1) w.w. in kidneys. Levels of polonium were not influenced by sampling location, sex, age and species of animals.

Aspergillus: a rare primary organism in soft-tissue infections.

Science.gov (United States)

Johnson, M A; Lyle, G; Hanly, M; Yeh, K A

1998-02-01

Nonclostridial necrotizing soft-tissue infections are usually polymicrobial, with greater than 90 per cent involving beta-hemolytic streptococci or coagulase-positive staphylococci. The remaining 10 per cent are usually due to Gram-negative enteric pathogens. We describe the case of a 46-year-old woman with bilateral lower extremity fungal soft tissue infections. She underwent multiple surgical debridements of extensive gangrenous necrosis of the skin and subcutaneous fat associated with severe acute arteritis. Histopathological examination revealed Aspergillus niger as the sole initial pathogen. Despite aggressive surgical debridement, allografts, and intravenous amphotericin B, her condition clinically deteriorated and she ultimately died of overwhelming infection. Treatment for soft-tissue infections include surgical debridement and intravenous antibiotics. More specifically, Aspergillus can be treated with intravenous amphotericin B, 5-fluorocytosine, and rifampin. Despite these treatment modalities, necrotizing fascitis is associated with a 60 per cent mortality rate. Primary fungal pathogens should be included in the differential diagnosis of soft-tissue infections.

Distortion of the Actin A-Triad Results in Contractile Disinhibition and Cardiomyopathy

Directory of Open Access Journals (Sweden)

Meera C. Viswanathan

2017-09-01

Full Text Available Striated muscle contraction is regulated by the movement of tropomyosin over the thin filament surface, which blocks or exposes myosin binding sites on actin. Findings suggest that electrostatic contacts, particularly those between K326, K328, and R147 on actin and tropomyosin, establish an energetically favorable F-actin-tropomyosin configuration, with tropomyosin positioned in a location that impedes actomyosin associations and promotes relaxation. Here, we provide data that directly support a vital role for these actin residues, termed the A-triad, in tropomyosin positioning in intact functioning muscle. By examining the effects of an A295S α-cardiac actin hypertrophic cardiomyopathy-causing mutation, over a range of increasingly complex in silico, in vitro, and in vivo Drosophila muscle models, we propose that subtle A-triad-tropomyosin perturbation can destabilize thin filament regulation, which leads to hypercontractility and triggers disease. Our efforts increase understanding of basic thin filament biology and help unravel the mechanistic basis of a complex cardiac disorder.

Organ-specific gene expression: the bHLH protein Sage provides tissue specificity to Drosophila FoxA.

Science.gov (United States)

Fox, Rebecca M; Vaishnavi, Aria; Maruyama, Rika; Andrew, Deborah J

2013-05-01

FoxA transcription factors play major roles in organ-specific gene expression, regulating, for example, glucagon expression in the pancreas, GLUT2 expression in the liver, and tyrosine hydroxylase expression in dopaminergic neurons. Organ-specific gene regulation by FoxA proteins is achieved through cooperative regulation with a broad array of transcription factors with more limited expression domains. Fork head (Fkh), the sole Drosophila FoxA family member, is required for the development of multiple distinct organs, yet little is known regarding how Fkh regulates tissue-specific gene expression. Here, we characterize Sage, a bHLH transcription factor expressed exclusively in the Drosophila salivary gland (SG). We show that Sage is required for late SG survival and normal tube morphology. We find that many Sage targets, identified by microarray analysis, encode SG-specific secreted cargo, transmembrane proteins, and the enzymes that modify these proteins. We show that both Sage and Fkh are required for the expression of Sage target genes, and that co-expression of Sage and Fkh is sufficient to drive target gene expression in multiple cell types. Sage and Fkh drive expression of the bZip transcription factor Senseless (Sens), which boosts expression of Sage-Fkh targets, and Sage, Fkh and Sens colocalize on SG chromosomes. Importantly, expression of Sage-Fkh target genes appears to simply add to the tissue-specific gene expression programs already established in other cell types, and Sage and Fkh cannot alter the fate of most embryonic cell types even when expressed early and continuously.

Textile Technologies and Tissue Engineering: A Path Towards Organ Weaving

Science.gov (United States)

Akbari, Mohsen; Tamayol, Ali; Bagherifard, Sara; Serex, Ludovic; Mostafalu, Pooria; Faramarzi, Negar; Mohammadi, Mohammad Hossein

2016-01-01

Textile technologies have recently attracted great attention as potential biofabrication tools for engineering tissue constructs. Using current textile technologies, fibrous structures can be designed and engineered to attain the required properties that are demanded by different tissue engineering applications. Several key parameters such as physiochemical characteristics of fibers, pore size and mechanical properties of the fabrics play important role in the effective use of textile technologies in tissue engineering. This review summarizes the current advances in the manufacturing of biofunctional fibers. Different textile methods such as knitting, weaving, and braiding are discussed and their current applications in tissue engineering are highlighted. PMID:26924450

A new stable GIP-Oxyntomodulin hybrid peptide improved bone strength both at the organ and tissue levels in genetically-inherited type 2 diabetes mellitus.

Science.gov (United States)

Mansur, Sity Aishah; Mieczkowska, Aleksandra; Flatt, Peter R; Bouvard, Beatrice; Chappard, Daniel; Irwin, Nigel; Mabilleau, Guillaume

2016-06-01

Obesity and type 2 diabetes mellitus (T2DM) progress worldwide with detrimental effects on several physiological systems including bone tissue mainly by affecting bone quality. Several gut hormones analogues have been proven potent in ameliorating bone quality. In the present study, we used the leptin receptor-deficient db/db mice as a model of obesity and severe T2DM to assess the extent of bone quality alterations at the organ and tissue levels. We also examined the beneficial effects of gut hormone therapy in this model by using a new triple agonist ([d-Ala(2)]GIP-Oxm) active at the GIP, GLP-1 and glucagon receptors. As expected, db/db mice presented with dramatic alterations of bone strength at the organ level associated with deterioration of trabecular and cortical microarchitectures and an augmentation in osteoclast numbers. At the tissue level, these animals presented also with alterations of bone strength (reduced hardness, indentation modulus and dissipated energy) with modifications of tissue mineral distribution, collagen glycation and collagen maturity. The use of [d-Ala(2)]GIP-Oxm considerably improved bone strength at the organ level with modest effects on trabecular microarchitecture. At the tissue level, [d-Ala(2)]GIP-Oxm ameliorated bone strength reductions with positive effects on collagen glycation and collagen maturity. This study provides support for including gut hormone analogues as possible new therapeutic strategies for improving bone quality in bone complications associated to T2DM. Copyright © 2016 Elsevier Inc. All rights reserved.

Elastin density: Link between histological and biomechanical properties of vaginal tissue in women with pelvic organ prolapse?

Science.gov (United States)

de Landsheere, Laurent; Brieu, Mathias; Blacher, Silvia; Munaut, Carine; Nusgens, Betty; Rubod, Chrystèle; Noel, Agnès; Foidart, Jean-Michel; Nisolle, Michelle; Cosson, Michel

2016-04-01

The aim of the study was to correlate histological and biomechanical characteristics of the vaginal wall in women with pelvic organ prolapse (POP). Tissue samples were collected from the anterior [point Ba; POP Questionnaire (POP-Q)] and/or posterior (point Bp; POP-Q) vaginal wall of 15 women who underwent vaginal surgery for POP. Both histological and biomechanical assessments were performed from the same tissue samples in 14 of 15 patients. For histological assessment, the density of collagen and elastin fibers was determined by combining high-resolution virtual imaging and computer-assisted digital image analysis. For biomechanical testing, uniaxial tension tests were performed to evaluate vaginal tissue stiffness at low (C0) and high (C1) deformation rates. Biomechanical testing highlights the hyperelastic behavior of the vaginal wall. At low strains (C0), vaginal tissue appeared stiffer when elastin density was low. We found a statistically significant inverse relationship between C0 and the elastin/collagen ratio (p = 0.048) in the lamina propria. However, at large strain levels (C1), no clear relationship was observed between elastin density or elastin/collagen ratio and stiffness, likely reflecting the large dispersion of the mechanical behavior of the tissue samples. Histological and biomechanical properties of the vaginal wall vary from patient to patient. This study suggests that elastin density deserves consideration as a relevant factor of vaginal stiffness in women with POP.

Bereaved donor families' experiences of organ and tissue donation, and perceived influences on their decision making.

Science.gov (United States)

Sque, Magi; Walker, Wendy; Long-Sutehall, Tracy; Morgan, Myfanwy; Randhawa, Gurch; Rodney, Amanda

2018-06-01

To elicit bereaved families' experiences of organ and tissue donation. A specific objective was to determine families' perceptions of how their experiences influenced donation decision-making. Retrospective, qualitative interviews were undertaken with 43 participants of 31 donor families to generate rich, informative data. Participant recruitment was via 10 National Health Service Trusts, representative of five regional organ donation services in the UK. Twelve families agreed to DBD, 18 agreed to DCD, 1 unknown. Participants' responses were contextualised using a temporal framework of 'The Past', which represented families' prior knowledge, experience, attitudes, beliefs, and intentions toward organ donation; 'The Present', which incorporated the moment in time when families experienced the potential for donation; and 'The Future', which corresponded to expectations and outcomes arising from the donation decision. Temporally interwoven experiences appeared to influence families' decisions to donate the organs of their deceased relative for transplantation. The influence of temporality on donation-decision making is worthy of consideration in the planning of future education, policy, practice, and research for improved rates of family consent to donation. Copyright © 2018 Elsevier Inc. All rights reserved.

Organ and tissue donation in a regional paediatric intensive care unit: evaluation of practice.

Science.gov (United States)

Carone, Laura; Alurkar, Shrirang; Kigozi, Phoebe; Vyas, Harish

2018-05-01

Approximately 2% of those on the organ transplant list in the UK are children. Early identification of donors and referral to organ donation teams (ODT) has proven to increase both the success rate of gaining consent and the number of organs actually retrieved. To evaluate the practice relating to organ donation for children receiving end-of-life care on a paediatric intensive care unit (PICU) measured against the National Guidelines. All children 0-18 who received their end-of-life care and died on the PICU. A retrospective cohort study of organ donation patterns including referral, approach, consent and donation. This involved a review of case notes on PICU between the years 2009 and 2014. One hundred five deaths were identified and 100 notes were examined and data analysed to ascertain if religion, age and length of stay on PICU impacted on practice. Eighty-six children met the early identification criteria for potential donors, 40 (46.5%) children were referred to the ODT and 33 (38.3%) families were approached regarding donation. Twenty-one (24.4%) families consented to donation. Seventeen donations took place with a total of 41 sets of organs/tissues retrieved. Despite the majority of children meeting early identification for potential donors, many were not being referred. All children on end-of-life care should be referred for potential organ donation. Organ donation needs to be seen as a priority for hospitals as a part of routine end-of-life care to help increase referral rates and give families the opportunity to donate. Many paediatric deaths are not referred for consideration of organ donation, despite guidelines stating that this process should be standard of care. Further optimization of referral rates may aid in increasing the number of organs available for donation. What is Known: • Shortage of organs continues to be a national problem. • NICE guidelines state that all patients who are on end-of-life care should have the option of organ donation

Should Society Encourage The Development Of 3D Printing Particularly 3D Bioprinting Of Tissues And Organs

Directory of Open Access Journals (Sweden)

Slaviana Pavlovich

2015-08-01

Full Text Available My aim is to discover moral and ethical sides of 3D printing which is a new technology and paradoxically a new phenomenon of the twenty-first century. Particularly 3D bioprinted organs and tissues is a controversial issue because this technological advancement may be viewed by society as a servant or it can even potentially become its master. For example in the health care system doctors may change their attitude to patients by using 3D bioprinted organs and tissues whenever it is needed also taking away responsibility from patients. Thus there can be great social and psychological consequences from 3D bioprinting in a long term. Furthermore Pete Basiliere an analyst in a worlds leading information technology research company suggests that 3D printing can also bring economic consequences resulting in the loss of at least 100 billion in intellectual property theft per year by 2018 globally. By analysing the economic psychological and social impact of the 3D printing technologies I want to research whether anyone is going be responsible for the 3D printing production and who is going to give a right to 3D bioprint.

Tissue Engineering of the Penis

Directory of Open Access Journals (Sweden)

Manish N. Patel

2011-01-01

Full Text Available Congenital disorders, cancer, trauma, or other conditions of the genitourinary tract can lead to significant organ damage or loss of function, necessitating eventual reconstruction or replacement of the damaged structures. However, current reconstructive techniques are limited by issues of tissue availability and compatibility. Physicians and scientists have begun to explore tissue engineering and regenerative medicine strategies for repair and reconstruction of the genitourinary tract. Tissue engineering allows the development of biological substitutes which could potentially restore normal function. Tissue engineering efforts designed to treat or replace most organs are currently being undertaken. Most of these efforts have occurred within the past decade. However, before these engineering techniques can be applied to humans, further studies are needed to ensure the safety and efficacy of these new materials. Recent progress suggests that engineered urologic tissues and cell therapy may soon have clinical applicability.

Textile Technologies and Tissue Engineering: A Path Toward Organ Weaving.

Science.gov (United States)

Akbari, Mohsen; Tamayol, Ali; Bagherifard, Sara; Serex, Ludovic; Mostafalu, Pooria; Faramarzi, Negar; Mohammadi, Mohammad Hossein; Khademhosseini, Ali

2016-04-06

Textile technologies have recently attracted great attention as potential biofabrication tools for engineering tissue constructs. Using current textile technologies, fibrous structures can be designed and engineered to attain the required properties that are demanded by different tissue engineering applications. Several key parameters such as physiochemical characteristics of fibers, microarchitecture, and mechanical properties of the fabrics play important roles in the effective use of textile technologies in tissue engineering. This review summarizes the current advances in the manufacturing of biofunctional fibers. Different textile methods such as knitting, weaving, and braiding are discussed and their current applications in tissue engineering are highlighted. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

CALDoseX-a software tool for the assessment of organ and tissue absorbed doses, effective dose and cancer risks in diagnostic radiology

International Nuclear Information System (INIS)

Kramer, R; Khoury, H J; Vieira, J W

2008-01-01

CALDose X is a software tool that provides the possibility of calculating incident air kerma (INAK) and entrance surface air kerma (ESAK), two important quantities used in x-ray diagnosis, based on the output of the x-ray equipment. Additionally, the software uses conversion coefficients (CCs) to assess the absorbed dose to organs and tissues of the human body, the effective dose as well as the patient's cancer risk for radiographic examinations. The CCs, ratios between organ or tissue absorbed doses and measurable quantities, have been calculated with the FAX06 and the MAX06 phantoms for 34 projections of 10 commonly performed x-ray examinations, for 40 combinations of tube potential and filtration ranging from 50 to 120 kVcp and from 2.0 to 5.0 mm aluminum, respectively, for various field positions, for 29 selected organs and tissues and simultaneously for the measurable quantities, INAK, ESAK and kerma area product (KAP). Based on the x-ray irradiation parameters defined by the user, CALDose X shows images of the phantom together with the position of the x-ray beam. By using true to nature voxel phantoms, CALDose X improves earlier software tools, which were mostly based on mathematical MIRD5-type phantoms, by using a less representative human anatomy.

Microfluidic Bioprinting of Heterogeneous 3D Tissue Constructs.

Science.gov (United States)

Colosi, Cristina; Costantini, Marco; Barbetta, Andrea; Dentini, Mariella

2017-01-01

3D bioprinting is an emerging field that can be described as a robotic additive biofabrication technology that has the potential to build tissues or organs. In general, bioprinting uses a computer-controlled printing device to accurately deposit cells and biomaterials into precise architectures with the goal of creating on demand organized multicellular tissue structures and eventually intra-organ vascular networks. The latter, in turn, will promote the host integration of the engineered tissue/organ in situ once implanted. Existing biofabrication techniques still lay behind this goal. Here, we describe a novel microfluidic printing head-integrated within a custom 3D bioprinter-that allows for the deposition of multimaterial and/or multicellular within a single scaffold by extruding simultaneously different bioinks or by rapidly switching between one bioink and another. The designed bioprinting method effectively moves toward the direction of creating viable tissues and organs for implantation in clinic and research in lab environments.

Environmental processes leading to the presence of organically bound plutonium in plant tissues consumed by animals

International Nuclear Information System (INIS)

Wildung, R.E.; Garland, T.R.; Cataldo, D.A.

1979-01-01

Using a proposed model for Pu behaviour to integrate current knowledge, information is presented on the chemical/biochemical processes governing the form of Pu in soils and plants and the relationship of these phenomena to gut absorption in animals. Regardless of the source term, Pu behaviour in the soil will be governed by the chemistry of Pu(IV), which predominates over Pu(VI) due to reductive reactions in the soil and at the plant root surface. The soil behaviour of Pu(IV) is governed by (1) hydrolysis, which results in insolubilization and sorption on solid phases, and (2) complexation with inorganic and organic ligands, which stabilize Pu(IV) against hydrolysis and increase solubility. These competing processes likely represent the rate-limiting step in the ingestion pathway because plants do not effectively discriminate against the soluble Pu(IV) ion. Following dissociation of soil Pu(IV) complexes at the outer root surface, Pu is transported across the plant root membrane as the Pu(IV) ion and translocated as Pu(IV) complexes with plant organic ligands. Redistribution of Pu occurs as the plant grows, with initial increases in stem tissues followed by accumulation in roots as the plant matures. The Pu concentration decreases up the plant and seeds contain the lowest Pu concentrations. The gastro-intestinal absorption of Pu requires the presence of soluble Pu forms and hydrolysis/complexation reactions in the gut likely govern solubility. The acidity of the gut is not sufficient to retard hydrolysis of Pu(IV). Therefore, the gastro-intestinal absorption of Pu organically bound in plant tissues is increased relative to Pu administered in hydrolysable solutions. (author)

Distribution of heavy metals in internal organs and tissues of Korean molluscan shellfish and potential risk to human health.

Science.gov (United States)

Mok, Jong Soo; Kwon, Ji Young; Son, Kwang Tae; Choi, Woo Seok; Kim, Poong Ho; Lee, Tae Seek; Kim, Ji Hoe

2015-09-01

Molluscan shellfish (gastropods and bivalves) were collected from major fish markets on the Korean coast and analyzed for mercury by direct Hg analyzer and for other metals, such as cadmium, lead, chromium, silver, nickel, copper and zinc, using inductively coupled plasma mass spectrometry. Distribution of heavy metals in muscles, internal organs and whole tissues were determined and a potential risk assessment was conducted to evaluate their hazard for human consumption. Heavy metals were accumulated significantly higher (P hazardous metals (Cd, Pb, and Hg) in all internal-organ samples were above the regulatory limit of Korea and the mean level in whole tissue samples of the selected gastropod species, bay scallop and comb pen shell, exceeded the limit (except in a few cases). The sum of the estimated dietary intake of Cd, Pb and Hg for each part of all tested species accounted for 1.59-16.94, 0.02-0.36, and 0.07-0.16% respectively, of the provisional tolerable daily intake adopted by the Joint FAO/WHO Expert Committee on Food Additives. The hazard index for each part of gastropods and bivalves was below 1.0, however, the maximum HI for internal organs of all analysed species was quite high (0.71). These results suggest that consumption of flesh after removing the internal organs of some molluscan shellfish (all gastropod species, bay scallop and comb pen shell) is a suitable way for reducing Cd exposure.

Extracellular matrix and tissue engineering applications

NARCIS (Netherlands)

Fernandes, H.A.M.; Moroni, Lorenzo; van Blitterswijk, Clemens; de Boer, Jan

2009-01-01

The extracellular matrix is a key component during regeneration and maintenance of tissues and organs, and it therefore plays a critical role in successful tissue engineering as well. Tissue engineers should recognise that engineering technology can be deduced from natural repair processes. Due to

Results from a horizon scan on risks associated with transplantation of human organs, tissues and cells: from donor to patient.

Science.gov (United States)

Herberts, C A; Park, M V D Z; Pot, J W G A; de Vries, C G J C A

2015-03-01

The successful transplantation of human materials such as organs, tissues and cells into patients does not only depend on the benefits, but also on the mitigation of risks. To gain insight into recent publications on risks associated with the process of transferring human materials from donor to recipient we performed a horizon scan by reviewing scientific literature and news websites of 2011 on this subject. We found there is ample information on how extended donor criteria, such as donor age, affect the survival rates of organs or patients. Interestingly, gender mismatch does not appear to be a major risk factor in organ rejection. Data on risks of donor tumor transmission was very scarce; however, risk categories for various tumor types have been suggested. In order to avoid rejection, a lot of research is directed towards engineering tissues from a patient's own tissues and cells. Some but not all of these developments have reached the clinic. Developments in the field of stem cell therapy are rapid. However, many hurdles are yet to be overcome before these cells can be applied on a large scale in the clinic. The processes leading to genetic abnormalities in cells differentiated from stem cells need to be identified in order to avoid transplantation of aberrant cells. New insights have been obtained on storage and preservation of human materials, a critical step for success of their clinical use. Likewise, quality management systems have been shown to improve the quality and safety of human materials used for transplantation.

Tissue specificity of the hormonal response in sex accessory tissues is associated with nuclear matrix protein patterns.

Science.gov (United States)

Getzenberg, R H; Coffey, D S

1990-09-01

The DNA of interphase nuclei have very specific three-dimensional organizations that are different in different cell types, and it is possible that this varying DNA organization is responsible for the tissue specificity of gene expression. The nuclear matrix organizes the three-dimensional structure of the DNA and is believed to be involved in the control of gene expression. This study compares the nuclear structural proteins between two sex accessory tissues in the same animal responding to the same androgen stimulation by the differential expression of major tissue-specific secretory proteins. We demonstrate here that the nuclear matrix is tissue specific in the rat ventral prostate and seminal vesicle, and undergoes characteristic alterations in its protein composition upon androgen withdrawal. Three types of nuclear matrix proteins were observed: 1) nuclear matrix proteins that are different and tissue specific in the rat ventral prostate and seminal vesicle, 2) a set of nuclear matrix proteins that either appear or disappear upon androgen withdrawal, and 3) a set of proteins that are common to both the ventral prostate and seminal vesicle and do not change with the hormonal state of the animal. Since the nuclear matrix is known to bind androgen receptors in a tissue- and steroid-specific manner, we propose that the tissue specificity of the nuclear matrix arranges the DNA in a unique conformation, which may be involved in the specific interaction of transcription factors with DNA sequences, resulting in tissue-specific patterns of secretory protein expression.

Bioactive scaffolds for the controlled formation of complex skeletal tissues

NARCIS (Netherlands)

Hofmann, S.; Garcia-Fuentes, M.; Eberli, D.

2011-01-01

Tissue Engineering may offer new treatment alternatives for organ replacement or repair deteriorated organs. Among the clinical applications of Tissue Engineering are the production of artificial skin for burn patients, tissue engineered trachea, cartilage for knee-replacement procedures, urinary

Emerging Biofabrication Strategies for Engineering Complex Tissue Constructs

DEFF Research Database (Denmark)

Pedde, R. Daniel; Mirani, Bahram; Navaei, Ali

2017-01-01

, outlines the use of common biomaterials and advanced hybrid scaffolds, and describes several design considerations including the structural, physical, biological, and economical parameters that are crucial for the fabrication of functional, complex, engineered tissues. Finally, the applications...... of these biofabrication strategies in neural, skin, connective, and muscle tissue engineering are explored.......The demand for organ transplantation and repair, coupled with a shortage of available donors, poses an urgent clinical need for the development of innovative treatment strategies for long-term repair and regeneration of injured or diseased tissues and organs. Bioengineering organs, by growing...

Nanotechnological Strategies for Biofabrication of Human Organs

Directory of Open Access Journals (Sweden)

Rodrigo A. Rezende

2012-01-01

Full Text Available Nanotechnology is a rapidly emerging technology dealing with so-called nanomaterials which at least in one dimension have size smaller than 100 nm. One of the most potentially promising applications of nanotechnology is in the area of tissue engineering, including biofabrication of 3D human tissues and organs. This paper focused on demonstrating how nanomaterials with nanolevel size can contribute to development of 3D human tissues and organs which have macrolevel organization. Specific nanomaterials such as nanofibers and nanoparticles are discussed in the context of their application for biofabricating 3D human tissues and organs. Several examples of novel tissue and organ biofabrication technologies based on using novel nanomaterials are presented and their recent limitations are analyzed. A robotic device for fabrication of compliant composite electrospun vascular graft is described. The concept of self-assembling magnetic tissue spheroids as an intermediate structure between nano- and macrolevel organization and building blocks for biofabrication of complex 3D human tissues and organs is introduced. The design of in vivo robotic bioprinter based on this concept and magnetic levitation of tissue spheroids labeled with magnetic nanoparticles is presented. The challenges and future prospects of applying nanomaterials and nanotechnological strategies in organ biofabrication are outlined.

Evaluation of the Procleix Ultrio Elite Assay and the Panther-System for Individual NAT Screening of Blood, Hematopoietic Stem Cell, Tissue and Organ Donors.

Science.gov (United States)

Heim, Albert

2016-05-01

The performance of the multiplex Procleix Ultrio Elite assay as individual donor nucleic acid test (ID-NAT) for the detection of HIV-1, HIV-2, HCV, and HBV was evaluated in a retrospective, single center study. ID-NAT results of 21,181 blood donors, 984 tissue donors, 293 hematopoietic stem cell donors and 4 organ donors were reviewed in synopsis with results of serological screening and additional discriminatory and repetitive NAT in case of positive donors. Specificity of the initial Procleix Ultrio Elite assay was 99.98% and after discriminatory testing 100.00%. Initially invalid results were observed in 75 of 21,181 blood donors (0.35%) but 16 of 984 tissue donors (1.62%, p donors. All these had valid negative ID-NAT results after repeated testing or testing of 1:5 diluted specimens in case of tissue donors. Occult hepatitis B (defined here as HBV DNAemia without HBsAg detection) was demonstrated by ID-NAT in two anti-HBc-positive tissue donors and suspected in two other tissue donors, where a definite diagnosis was not achieved due to the insufficient sample volumes available. The Procleix Ultrio Elite assay proved to be specific, robust and rapid. Therefore, routine ID-NAT may also be feasible for organ and granulocyte donors.

Hormonal regulation of epithelial organization in a three-dimensional breast tissue culture model.

Science.gov (United States)

Speroni, Lucia; Whitt, Gregory S; Xylas, Joanna; Quinn, Kyle P; Jondeau-Cabaton, Adeline; Barnes, Clifford; Georgakoudi, Irene; Sonnenschein, Carlos; Soto, Ana M

2014-01-01

The establishment of hormone target breast cells in the 1970's resulted in suitable models for the study of hormone control of cell proliferation and gene expression using two-dimensional (2D) cultures. However, to study mammogenesis and breast tumor development in vitro, cells must be able to organize in three-dimensional (3D) structures like in the tissue. We now report the development of a hormone-sensitive 3D culture model for the study of mammogenesis and neoplastic development. Hormone-sensitive T47D breast cancer cells respond to estradiol in a dose-dependent manner by forming complex epithelial structures. Treatment with the synthetic progestagen promegestone, in the presence of estradiol, results in flat epithelial structures that display cytoplasmic projections, a phenomenon reported to precede side-branching. Additionally, as in the mammary gland, treatment with prolactin in the presence of estradiol induces budding structures. These changes in epithelial organization are accompanied by collagen remodeling. Collagen is the major acellular component of the breast stroma and an important player in tumor development and progression. Quantitative analysis of second harmonic generation of collagen fibers revealed that collagen density was more variable surrounding budding and irregularly shaped structures when compared to more regular structures; suggesting that fiber organization in the former is more anisotropic than in the latter. In sum, this new 3D model recapitulates morphogenetic events modulated by mammogenic hormones in the breast, and is suitable for the evaluation of therapeutic agents.

Tissue Engineering Applications of Three-Dimensional Bioprinting.

Science.gov (United States)

Zhang, Xiaoying; Zhang, Yangde

2015-07-01

Recent advances in tissue engineering have adapted the additive manufacturing technology, also known as three-dimensional printing, which is used in several industrial applications, for the fabrication of bioscaffolds and viable tissue and/or organs to overcome the limitations of other in vitro conventional methods. 3D bioprinting technology has gained enormous attention as it enabled 3D printing of a multitude of biocompatible materials, different types of cells and other supporting growth factors into complex functional living tissues in a 3D format. A major advantage of this technology is its ability for simultaneously 3D printing various cell types in defined spatial locations, which makes this technology applicable to regenerative medicine to meet the need for suitable for transplantation suitable organs and tissues. 3D bioprinting is yet to successfully overcome the many challenges related to building 3D structures that closely resemble native organs and tissues, which are complex structures with defined microarchitecture and a variety of cell types in a confined area. An integrated approach with a combination of technologies from the fields of engineering, biomaterials science, cell biology, physics, and medicine is required to address these complexities. Meeting this challenge is being made possible by directing the 3D bioprinting to manufacture biomimetic-shaped 3D structures, using organ/tissue images, obtained from magnetic resonance imaging and computerized tomography, and employing computer-aided design and manufacturing technologies. Applications of 3D bioprinting include the generation of multilayered skin, bone, vascular grafts, heart valves, etc. The current 3D bioprinting technologies need to be improved with respect to the mechanical strength and integrity in the manufactured constructs as the presently used biomaterials are not of optimal viscosity. A better understanding of the tissue/organ microenvironment, which consists of multiple types of

Tissue architecture: the ultimate regulator of breast epithelial function

Energy Technology Data Exchange (ETDEWEB)

Bissell, Mina J; Rizki, Aylin; Mian, Saira

2003-10-20

A problem in developmental biology that continues to take center stage is how higher organisms generate diverse tissues and organs given the same cellular genotype. In cell and tumor biology, the key question is not the production of form, but its preservation: how do tissues and organs maintain homeostasis, and how do cells within tissues lose or overcome these controls in cancer? Undoubtedly, mechanisms that maintain tissue specificity should share features with those employed to drive formation of the tissues. However, they are unlikely to be identical. At a simplistic level, developmental pathways may be thought of as a series of extremely rapid short-term events. Each new step depends on what came before, and the outcome is the organism itself at birth. All organs, with a few notable exceptions, such as the mammary gland and the brain, 'arrive' together and are complete when the organism is born. In mice and humans, these events occur in a mere 21 days and 9 months respectively. The stability of the differentiated state and the homeostasis of the organism, on the other hand, will last 40-110 times longer. How does the organism achieve this feat? How are tissues maintained? These questions also relate fundamentally to how tissues become malignant and, although not discussed here, to aging. While there is much literature on differentiation - loosely defined as the gain of a single or a series of functions - we know much less about the forces and the pathways that maintain organ morphology and function as a unit. This may be partly because it is difficult to study a tissue as a unit in vivo and there are few techniques that allow maintenance of organs in vitro long enough and in such a way as to make cell and molecular biology experiments possible. Techniques for culturing cells in three-dimensional gels (3D) as a surrogate for tissues, however, have been steadily improving and the method is now used by several laboratories. In this commentary we

Hierarchical Design of Tissue Regenerative Constructs.

Science.gov (United States)

Rose, Jonas C; De Laporte, Laura

2018-03-01

The worldwide shortage of organs fosters significant advancements in regenerative therapies. Tissue engineering and regeneration aim to supply or repair organs or tissues by combining material scaffolds, biochemical signals, and cells. The greatest challenge entails the creation of a suitable implantable or injectable 3D macroenvironment and microenvironment to allow for ex vivo or in vivo cell-induced tissue formation. This review gives an overview of the essential components of tissue regenerating scaffolds, ranging from the molecular to the macroscopic scale in a hierarchical manner. Further, this review elaborates about recent pivotal technologies, such as photopatterning, electrospinning, 3D bioprinting, or the assembly of micrometer-scale building blocks, which enable the incorporation of local heterogeneities, similar to most native extracellular matrices. These methods are applied to mimic a vast number of different tissues, including cartilage, bone, nerves, muscle, heart, and blood vessels. Despite the tremendous progress that has been made in the last decade, it remains a hurdle to build biomaterial constructs in vitro or in vivo with a native-like structure and architecture, including spatiotemporal control of biofunctional domains and mechanical properties. New chemistries and assembly methods in water will be crucial to develop therapies that are clinically translatable and can evolve into organized and functional tissues. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Fell-Muir lecture: connective tissue growth factor (CCN2) – a pernicious and pleiotropic player in the development of kidney fibrosis

Science.gov (United States)

Mason, Roger M

2013-01-01

Connective tissue growth factor (CTGF, CCN2) is a member of the CCN family of matricellular proteins. It interacts with many other proteins, including plasma membrane proteins, modulating cell function. It is expressed at low levels in normal adult kidney cells but is increased in kidney diseases, playing important roles in inflammation and in the development of glomerular and interstitial fibrosis in chronic disease. This review reports the evidence for its expression in human and animal models of chronic kidney disease and summarizes data showing that anti-CTGF therapy can successfully attenuate fibrotic changes in several such models, suggesting that therapies targeting CTGF and events downstream of it in renal cells may be useful for the treatment of human kidney fibrosis. Connective tissue growth factor stimulates the development of fibrosis in the kidney in many ways including activating cells to increase extracellular matrix synthesis, inducing cell cycle arrest and hypertrophy, and prolonging survival of activated cells. The relationship between CTGF and the pro-fibrotic factor TGFβ is examined and mechanisms by which CTGF promotes signalling by the latter are discussed. No specific cellular receptors for CTGF have been discovered but it interacts with and activates several plasma membrane proteins including low-density lipoprotein receptor-related protein (LRP)-1, LRP-6, tropomyosin-related kinase A, integrins and heparan sulphate proteoglycans. Intracellular signalling and downstream events triggered by such interactions are reviewed. Finally, the relationships between CTGF and several anti-fibrotic factors, such as bone morphogenetic factor-4 (BMP4), BMP7, hepatocyte growth factor, CCN3 and Oncostatin M, are discussed. These may determine whether injured tissue heals or progresses to fibrosis. PMID:23110747

Laser-induced Breakdown Spectroscopy: A New Approach for Nanoparticle's Mapping and Quantification in Organ Tissue

Science.gov (United States)

Sancey, Lucie; Motto-Ros, Vincent; Kotb, Shady; Wang, Xiaochun; Lux, François; Panczer, Gérard; Yu, Jin; Tillement, Olivier

2014-01-01

Emission spectroscopy of laser-induced plasma was applied to elemental analysis of biological samples. Laser-induced breakdown spectroscopy (LIBS) performed on thin sections of rodent tissues: kidneys and tumor, allows the detection of inorganic elements such as (i) Na, Ca, Cu, Mg, P, and Fe, naturally present in the body and (ii) Si and Gd, detected after the injection of gadolinium-based nanoparticles. The animals were euthanized 1 to 24 hr after intravenous injection of particles. A two-dimensional scan of the sample, performed using a motorized micrometric 3D-stage, allowed the infrared laser beam exploring the surface with a lateral resolution less than 100 μm. Quantitative chemical images of Gd element inside the organ were obtained with sub-mM sensitivity. LIBS offers a simple and robust method to study the distribution of inorganic materials without any specific labeling. Moreover, the compatibility of the setup with standard optical microscopy emphasizes its potential to provide multiple images of the same biological tissue with different types of response: elemental, molecular, or cellular. PMID:24962015

Donation FAQs (Bone and Tissue Allografts)

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... Biologics is affiliated with organ, eye and tissue procurement agencies throughout the U.S. They typically ... Visit DonateLife.net and learn how your gift of tissue can give bring new life to ...

Random lasing in human tissues

International Nuclear Information System (INIS)

Polson, Randal C.; Vardeny, Z. Valy

2004-01-01

A random collection of scatterers in a gain medium can produce coherent laser emission lines dubbed 'random lasing'. We show that biological tissues, including human tissues, can support coherent random lasing when infiltrated with a concentrated laser dye solution. To extract a typical random resonator size within the tissue we average the power Fourier transform of random laser spectra collected from many excitation locations in the tissue; we verified this procedure by a computer simulation. Surprisingly, we found that malignant tissues show many more laser lines compared to healthy tissues taken from the same organ. Consequently, the obtained typical random resonator was found to be different for healthy and cancerous tissues, and this may lead to a technique for separating malignant from healthy tissues for diagnostic imaging

Biomaterials for tissue engineering applications.

Science.gov (United States)

Keane, Timothy J; Badylak, Stephen F

2014-06-01

With advancements in biological and engineering sciences, the definition of an ideal biomaterial has evolved over the past 50 years from a substance that is inert to one that has select bioinductive properties and integrates well with adjacent host tissue. Biomaterials are a fundamental component of tissue engineering, which aims to replace diseased, damaged, or missing tissue with reconstructed functional tissue. Most biomaterials are less than satisfactory for pediatric patients because the scaffold must adapt to the growth and development of the surrounding tissues and organs over time. The pediatric community, therefore, provides a distinct challenge for the tissue engineering community. Copyright © 2014. Published by Elsevier Inc.

The self-assembling process and applications in tissue engineering

Science.gov (United States)

Lee, Jennifer K.; Link, Jarrett M.; Hu, Jerry C. Y.; Athanasiou, Kyriacos A.

2018-01-01

Tissue engineering strives to create neotissues capable of restoring function. Scaffold-free technologies have emerged that can recapitulate native tissue function without the use of an exogenous scaffold. This chapter will survey, in particular, the self-assembling and self-organization processes as scaffold-free techniques. Characteristics and benefits of each process are described, and key examples of tissues created using these scaffold-free processes are examined to provide guidance for future tissue engineering developments. This chapter aims to explore the potential of self-assembly and self-organization scaffold-free approaches, detailing the recent progress in the in vitro tissue engineering of biomimetic tissues with these methods, toward generating functional tissue replacements. PMID:28348174

The Application of Tissue Engineering Procedures to Repair the Larynx

Science.gov (United States)

Ringel, Robert L.; Kahane, Joel C.; Hillsamer, Peter J.; Lee, Annie S.; Badylak, Stephen F.

2006-01-01

The field of tissue engineering/regenerative medicine combines the quantitative principles of engineering with the principles of the life sciences toward the goal of reconstituting structurally and functionally normal tissues and organs. There has been relatively little application of tissue engineering efforts toward the organs of speech, voice,…

"Why throw away something useful?": Attitudes and opinions of people treated for bipolar disorder and their relatives on organ and tissue donation.

Science.gov (United States)

Padoan, Carolina S; Garcia, Lucas F; Rodrigues, Aline A; Patusco, Lucas M; Atz, Mariana V; Kapczinski, Flavio; Goldim, José R; Magalhães, Pedro V S

2017-03-01

In regard to mental illness, brain donation is essential for the biological investigation of central pathology. Nevertheless, little is known about the thoughts of people with mental disorders on tissue donation for research. Here, our objective was to understand the attitudes and opinions of people treated for bipolar disorder and their relatives regarding donation in general, and particularly donation for research. This is a qualitative study that used in-depth interviews to determine the thoughts of participants regarding tissue donation for research. Theoretical sampling was used as a recruitment method. Grounded theory was used as a framework for content analyses of the interviews. A semi-structured interview guide was applied with the topics: donation in general; donation for research; mental health and body organs; opinion regarding donation; feelings aroused by the topic. Although all participants were aware of organ donation for transplant, they were surprised that tissue could be donated for research. Nevertheless, once they understood the concept they were usually in favor of the idea. Although participants demonstrated a general lack of knowledge on donation for research, they were willing to learn more and viewed it as a good thing, with altruistic reasons often cited as a motive for donation. We speculate that bridging this knowledge gap may be a fundamental step towards a more ethical postmortem tissue donation process.

Proangiogenic scaffolds as functional templates for cardiac tissue engineering

OpenAIRE

Madden, Lauran R.; Mortisen, Derek J.; Sussman, Eric M.; Dupras, Sarah K.; Fugate, James A.; Cuy, Janet L.; Hauch, Kip D.; Laflamme, Michael A.; Murry, Charles E.; Ratner, Buddy D.

2010-01-01

We demonstrate here a cardiac tissue-engineering strategy addressing multicellular organization, integration into host myocardium, and directional cues to reconstruct the functional architecture of heart muscle. Microtemplating is used to shape poly(2-hydroxyethyl methacrylate-co-methacrylic acid) hydrogel into a tissue-engineering scaffold with architectures driving heart tissue integration. The construct contains parallel channels to organize cardiomyocyte bundles, supported by micrometer-s...

Introduction to tissue engineering applications and challenges

CERN Document Server

Birla, Ravi

2014-01-01

Covering a progressive medical field, Tissue Engineering describes the innovative process of regenerating human cells to restore or establish normal function in defective organs. As pioneering individuals look ahead to the possibility of generating entire organ systems, students may turn to this textbook for a comprehensive understanding and preparation for the future of regenerative medicine. This book explains chemical stimulations, the bioengineering of specific organs, and treatment plans for chronic diseases. It is a must-read for tissue engineering students and practitioners.

Tissue Sampling Guides for Porcine Biomedical Models.

Science.gov (United States)

Albl, Barbara; Haesner, Serena; Braun-Reichhart, Christina; Streckel, Elisabeth; Renner, Simone; Seeliger, Frank; Wolf, Eckhard; Wanke, Rüdiger; Blutke, Andreas

2016-04-01

This article provides guidelines for organ and tissue sampling adapted to porcine animal models in translational medical research. Detailed protocols for the determination of sampling locations and numbers as well as recommendations on the orientation, size, and trimming direction of samples from ∼50 different porcine organs and tissues are provided in the Supplementary Material. The proposed sampling protocols include the generation of samples suitable for subsequent qualitative and quantitative analyses, including cryohistology, paraffin, and plastic histology; immunohistochemistry;in situhybridization; electron microscopy; and quantitative stereology as well as molecular analyses of DNA, RNA, proteins, metabolites, and electrolytes. With regard to the planned extent of sampling efforts, time, and personnel expenses, and dependent upon the scheduled analyses, different protocols are provided. These protocols are adjusted for (I) routine screenings, as used in general toxicity studies or in analyses of gene expression patterns or histopathological organ alterations, (II) advanced analyses of single organs/tissues, and (III) large-scale sampling procedures to be applied in biobank projects. Providing a robust reference for studies of porcine models, the described protocols will ensure the efficiency of sampling, the systematic recovery of high-quality samples representing the entire organ or tissue as well as the intra-/interstudy comparability and reproducibility of results. © The Author(s) 2016.

Potential and Actual Neonatal Organ and Tissue Donation After Circulatory Determination of Death.

Science.gov (United States)

Stiers, Justin; Aguayo, Cecile; Siatta, Angela; Presson, Angela P; Perez, Richard; DiGeronimo, Robert

2015-07-01

The need for transplants continues to exceed organ and tissue donor availability. Although recent surgical advances have resulted in successful transplants using very small pediatric donors, including neonates, the actual practice of neonatal organ donation after circulatory determination of death (DCDD) remains uncommon. To describe the percentage of neonates potentially eligible for DCDD, including those who underwent successful donation, and reasons for ineligibility in those who did not in a single neonatal intensive care unit (NICU). We obtained data from the Children's Hospital Neonatal Database and Intermountain Donor Services (IDS) organ procurement records. The 136 deaths that occurred in the NICU of the Primary Children's Hospital, Salt Lake City, Utah, from January 1, 2010, through May 7, 2013, were reviewed retrospectively from January 12 through July 1, 2014, to determine potential eligibility for DCDD as determined by IDS minimum eligibility criteria (requirement of life-sustaining interventions and weight >2 kg). For patients who did not undergo DCDD, we reviewed records to determine the reasons for ineligibility. Potential eligibility for DCDD among neonates who died in the study NICU. Of 136 deaths in the NICU, 60 (44.1%) met criteria for DCDD; however, fewer than 10% were referred appropriately to the regional organ procurement organization for evaluation. Forty-five neonates (33.1%) ultimately died within 90 minutes of withdrawal of life-sustaining interventions and thus would have been eligible for organ donation based on warm ischemic time. The most common causes of death among the 60 potentially eligible neonatal donors were neonatal encephalopathy (n = 17) and multiple congenital anomalies (n = 14). Nonreferral or late referral by the medical team was the most frequent reason for donor ineligibility, including 49 neonates (36.0%). Overall, only 4 neonates (2.9%) underwent successful DCDD. Although almost half of all neonatal deaths

Normal tissue complication probability (NTCP), the clinician,s perspective

International Nuclear Information System (INIS)

Yeoh, E.K.

2011-01-01

Full text: 3D radiation treatment planning has enabled dose distributions to be related to the volume of normal tissues irradiated. The dose volume histograms thus derived have been utilized to set NTCP dose constraints to facilitate optimization of treatment planning. However, it is not widely appreciated that a number of important variables other than DYH's which determine NTCP in the individual patient. These variables will be discussed under the headings of patient and treatment related as well as tumour related factors. Patient related factors include age, co-morbidities such as connective tissue disease and diabetes mellitus, previous tissue/organ damage, tissue architectural organization (parallel or serial), regional tissue/organ and individual tissue/organ radiosensitivities as well as the development of severe acute toxicity. Treatment related variables which need to be considered include dose per fraction (if not the conventional 1.8012.00 Gy/fraction, particularly for IMRT), number of fractions and total dose, dose rate (particularly if combined with brachytherapy) and concurrent chemotherapy or other biological dose modifiers. Tumour related factors which impact on NTCP include infiltration of normal tissue/organ usually at presentation leading to compromised function but also with recurrent disease after radiation therapy as well as variable tumour radiosensitivities between and within tumour types. Whilst evaluation of DYH data is a useful guide in the choice of treatment plan, the current state of knowledge requires the clinician to make an educated judgement based on a consideration of the other factors.

Bone Tissue Donation: Tendency and Hurdles.

Science.gov (United States)

El Hage, S; Dos Santos, M J; de Moraes, E L; de Barros E Silva, L B

2018-03-01

The aim of this study was to identify the percentage of bone tissue donation in a brain death situation and the tendency of donation rate of this tissue in an organ procurement organization in the county of Sao Paulo from 2001 to 2016. It is a retrospective and quantitative study, based on the Organ and Tissue Donation Term of donors who died of brain death between 2001 and 2016. A logistic regression model was applied, and the odds of donation were identified throughout the years, regarding the odds ratio different from zero. Finally, it was measured the accuracy of the odds ratio through the confidence interval. The analysis has shown a significant change on the trend of bone donation (P 1, indicating that the donation rate has increased. However, the percentage of growth is still considered low. The study evidences a growth trend regarding the donation of bone tissue, but the percentage is still too low to adequately meet the demand of patients who need this modality of therapeutic intervention. It is believed that educational campaigns of donation are not emphasizing the donation of tissues for transplantation, which may be directly impacting their consent rates. Copyright © 2018 Elsevier Inc. All rights reserved.

Heterogeneity of Scaffold Biomaterials in Tissue Engineering

Directory of Open Access Journals (Sweden)

Lauren Edgar

2016-05-01

Full Text Available Tissue engineering (TE offers a potential solution for the shortage of transplantable organs and the need for novel methods of tissue repair. Methods of TE have advanced significantly in recent years, but there are challenges to using engineered tissues and organs including but not limited to: biocompatibility, immunogenicity, biodegradation, and toxicity. Analysis of biomaterials used as scaffolds may, however, elucidate how TE can be enhanced. Ideally, biomaterials should closely mimic the characteristics of desired organ, their function and their in vivo environments. A review of biomaterials used in TE highlighted natural polymers, synthetic polymers, and decellularized organs as sources of scaffolding. Studies of discarded organs supported that decellularization offers a remedy to reducing waste of donor organs, but does not yet provide an effective solution to organ demand because it has shown varied success in vivo depending on organ complexity and physiological requirements. Review of polymer-based scaffolds revealed that a composite scaffold formed by copolymerization is more effective than single polymer scaffolds because it allows copolymers to offset disadvantages a single polymer may possess. Selection of biomaterials for use in TE is essential for transplant success. There is not, however, a singular biomaterial that is universally optimal.

Evaluation of the Procleix Ultrio Elite Assay and the Panther-System for Individual NAT Screening of Blood, Hematopoietic Stem Cell, Tissue and Organ Donors

Science.gov (United States)

Heim, Albert

2016-01-01

Summary Background The performance of the multiplex Procleix Ultrio Elite assay as individual donor nucleic acid test (ID-NAT) for the detection of HIV-1, HIV-2, HCV, and HBV was evaluated in a retrospective, single center study. Methods ID-NAT results of 21,181 blood donors, 984 tissue donors, 293 hematopoietic stem cell donors and 4 organ donors were reviewed in synopsis with results of serological screening and additional discriminatory and repetitive NAT in case of positive donors. Results Specificity of the initial Procleix Ultrio Elite assay was 99.98% and after discriminatory testing 100.00%. Initially invalid results were observed in 75 of 21,181 blood donors (0.35%) but 16 of 984 tissue donors (1.62%, p donors. All these had valid negative ID-NAT results after repeated testing or testing of 1:5 diluted specimens in case of tissue donors. Occult hepatitis B (defined here as HBV DNAemia without HBsAg detection) was demonstrated by ID-NAT in two anti-HBc-positive tissue donors and suspected in two other tissue donors, where a definite diagnosis was not achieved due to the insufficient sample volumes available. Conclusion The Procleix Ultrio Elite assay proved to be specific, robust and rapid. Therefore, routine ID-NAT may also be feasible for organ and granulocyte donors. PMID:27403089

38 CFR 1.485a - Eye, organ and tissue donation.

Science.gov (United States)

2010-07-01

... centers must verify annually in January of each calendar year with the Food and Drug Administration (FDA) that an eye bank or tissue bank has complied with the FDA registration requirements of 21 CFR part 1271 and that the registration status is active before permitting an eye bank or tissue bank to receive...

Artificial organs versus regenerative medicine: is it true?

Science.gov (United States)

Nosé, Yukihiko; Okubo, Hisashi

2003-09-01

Individuals engaged in the fields of artificial kidney and artificial heart have often mistakenly stated that "the era of artificial organs is over; regenerative medicine is the future." Contrarily, we do not believe artificial organs and regenerative medicine are different medical technologies. As a matter of fact, artificial organs developed during the last 50 years have been used as a bridge to regeneration. The only difference between regenerative medicine and artificial organs is that artificial organs for the bridge to regeneration promote tissue regeneration in situ, instead of outside the body (for example, vascular prostheses, neuroprostheses, bladder substitutes, skin prostheses, bone prostheses, cartilage prostheses, ligament prostheses, etc.). All of these artificial organs are successful because tissue regeneration over a man-made prosthesis is established inside the patient's body (artificial organs to support regeneration). Another usage of the group of artificial organs for the bridge to regeneration is to sustain the functions of the patient's diseased organs during the regeneration process of the body's healthy tissues and/or organs. This particular group includes artificial kidney, hepatic assist, respiratory assist, and circulatory assist. Proof of regeneration of these healthy tissues and/or organs is demonstrated in the short-term recovery of end-stage organ failure patients (artificial organs for bridge to regeneration). A third group of artificial organs for the bridge to regeneration accelerates the regenerating process of the patient's healthy tissues and organs. This group includes neurostimulators, artificial blood (red cells) blood oxygenators, and plasmapheresis devices, including hemodiafiltrators. So-called "therapeutic artificial organs" fall into this category (artificial organs to accelerate regeneration). Thus, almost all of today's artificial organs are useful in the bridge to regeneration of healthy natural tissues and organs

Tissue distribution of 14C-diazepam and its metabolites in rats

International Nuclear Information System (INIS)

Igari, Y.; Sugiyama, Y.; Sawada, Y.; Iga, T.; Hanano, M.

1982-01-01

We have kinetically investigated the tissue distribution of 14 C-diazepam and described the appearance and disappearance of its metabolites (3-hydroxydiazepam, desmethyldiazepam, and oxazepam) following a single iv injection of 14 C-diazepam into rats. Significant amounts of oxazepam were detected in plasma and various tissues in the rat, contrary to previous reports. Concentration-time profiles of diazepam in the main disposing organs (liver, kidney, and lung) and the other organs (brain, heart, and small intestine) indicated that diazepam was distributed rapidly to these organs. Concentration-time profiles of diazepam in the main tissues for drug distribution (skin and adipose) indicated that diazepam was slowly distributed to these tissues, whereas that in muscle, which is also responsible for drug distribution, indicated that diazepam was less rapidly distributed to this tissue. Metabolites appeared in plasma and various tissues or organs immediately after iv injection of diazepam. Metabolites levels in plasma and various tissues or organs were significantly lower than that of diazepam except for liver and small intestine, where metabolites levels were higher compared to that of diazepam and metabolites exhibited a considerable persistence

Biomimetic heterogenous elastic tissue development.

Science.gov (United States)

Tsai, Kai Jen; Dixon, Simon; Hale, Luke Richard; Darbyshire, Arnold; Martin, Daniel; de Mel, Achala

2017-01-01

There is an unmet need for artificial tissue to address current limitations with donor organs and problems with donor site morbidity. Despite the success with sophisticated tissue engineering endeavours, which employ cells as building blocks, they are limited to dedicated labs suitable for cell culture, with associated high costs and long tissue maturation times before available for clinical use. Direct 3D printing presents rapid, bespoke, acellular solutions for skull and bone repair or replacement, and can potentially address the need for elastic tissue, which is a major constituent of smooth muscle, cartilage, ligaments and connective tissue that support organs. Thermoplastic polyurethanes are one of the most versatile elastomeric polymers. Their segmented block copolymeric nature, comprising of hard and soft segments allows for an almost limitless potential to control physical properties and mechanical behaviour. Here we show direct 3D printing of biocompatible thermoplastic polyurethanes with Fused Deposition Modelling, with a view to presenting cell independent in-situ tissue substitutes. This method can expeditiously and economically produce heterogenous, biomimetic elastic tissue substitutes with controlled porosity to potentially facilitate vascularisation. The flexibility of this application is shown here with tubular constructs as exemplars. We demonstrate how these 3D printed constructs can be post-processed to incorporate bioactive molecules. This efficacious strategy, when combined with the privileges of digital healthcare, can be used to produce bespoke elastic tissue substitutes in-situ, independent of extensive cell culture and may be developed as a point-of-care therapy approach.

Effects of Re-heating Tissue Samples to Core Body Temperature on High-Velocity Ballistic Projectile-tissue Interactions.

Science.gov (United States)

Humphrey, Caitlin; Henneberg, Maciej; Wachsberger, Christian; Maiden, Nicholas; Kumaratilake, Jaliya

2017-11-01

Damage produced by high-speed projectiles on organic tissue will depend on the physical properties of the tissues. Conditioning organic tissue samples to human core body temperature (37°C) prior to conducting ballistic experiments enables their behavior to closely mimic that of living tissues. To minimize autolytic changes after death, the tissues are refrigerated soon after their removal from the body and re-heated to 37°C prior to testing. This research investigates whether heating 50-mm-cube samples of porcine liver, kidney, and heart to 37°C for varying durations (maximum 7 h) can affect the penetration response of a high-speed, steel sphere projectile. Longer conditioning times for heart and liver resulted in a slight loss of velocity/energy of the projectile, but the reverse effect occurred for the kidney. Possible reasons for these trends include autolytic changes causing softening (heart and liver) and dehydration causing an increase in density (kidney). © 2017 American Academy of Forensic Sciences.

Assessment of Abdominal Adipose Tissue and Organ Fat Content by Magnetic Resonance Imaging

Science.gov (United States)

Hu, Houchun H.; Nayak, Krishna S.; Goran, Michael I.

2010-01-01

As the prevalence of obesity continues to rise, rapid and accurate tools for assessing abdominal body and organ fat quantity and distribution are critically needed to assist researchers investigating therapeutic and preventive measures against obesity and its comorbidities. Magnetic resonance imaging (MRI) is the most promising modality to address such need. It is non-invasive, utilizes no ionizing radiation, provides unmatched 3D visualization, is repeatable, and is applicable to subject cohorts of all ages. This article is aimed to provide the reader with an overview of current and state-of-the-art techniques in MRI and associated image analysis methods for fat quantification. The principles underlying traditional approaches such as T1-weighted imaging and magnetic resonance spectroscopy as well as more modern chemical-shift imaging techniques are discussed and compared. The benefits of contiguous 3D acquisitions over 2D multi-slice approaches are highlighted. Typical post-processing procedures for extracting adipose tissue depot volumes and percent organ fat content from abdominal MRI data sets are explained. Furthermore, the advantages and disadvantages of each MRI approach with respect to imaging parameters, spatial resolution, subject motion, scan time, and appropriate fat quantitative endpoints are also provided. Practical considerations in implementing these methods are also presented. PMID:21348916

ROCK1-directed basement membrane positioning coordinates epithelial tissue polarity.

Science.gov (United States)

Daley, William P; Gervais, Elise M; Centanni, Samuel W; Gulfo, Kathryn M; Nelson, Deirdre A; Larsen, Melinda

2012-01-01

The basement membrane is crucial for epithelial tissue organization and function. However, the mechanisms by which basement membrane is restricted to the basal periphery of epithelial tissues and the basement membrane-mediated signals that regulate coordinated tissue organization are not well defined. Here, we report that Rho kinase (ROCK) controls coordinated tissue organization by restricting basement membrane to the epithelial basal periphery in developing mouse submandibular salivary glands, and that ROCK inhibition results in accumulation of ectopic basement membrane throughout the epithelial compartment. ROCK-regulated restriction of PAR-1b (MARK2) localization in the outer basal epithelial cell layer is required for basement membrane positioning at the tissue periphery. PAR-1b is specifically required for basement membrane deposition, as inhibition of PAR-1b kinase activity prevents basement membrane deposition and disrupts overall tissue organization, and suppression of PAR-1b together with ROCK inhibition prevents interior accumulations of basement membrane. Conversely, ectopic overexpression of wild-type PAR-1b results in ectopic interior basement membrane deposition. Significantly, culture of salivary epithelial cells on exogenous basement membrane rescues epithelial organization in the presence of ROCK1 or PAR-1b inhibition, and this basement membrane-mediated rescue requires functional integrin β1 to maintain epithelial cell-cell adhesions. Taken together, these studies indicate that ROCK1/PAR-1b-dependent regulation of basement membrane placement is required for the coordination of tissue polarity and the elaboration of tissue structure in the developing submandibular salivary gland.

Protein expression analysis of inflammation-related colon carcinogenesis

Directory of Open Access Journals (Sweden)

Yasui Yumiko

2009-01-01

Full Text Available Background: Chronic inflammation is a risk factor for colorectal cancer (CRC development. The aim of this study was to determine the differences in protein expression between CRC and the surrounding nontumorous colonic tissues in the mice that received azoxymethane (AOM and dextran sodium sulfate (DSS using a proteomic analysis. Materials and Methods: Male ICR mice were given a single intraperitoneal injection of AOM (10 mg/kg body weight, followed by 2% (w/v DSS in their drinking water for seven days, starting one week after the AOM injection. Colonic adenocarcinoma developed after 20 weeks and a proteomics analysis based on two-dimensional gel electrophoresis and ultraflex TOF/TOF mass spectrometry was conducted in the cancerous and nontumorous tissue specimens. Results: The proteomic analysis revealed 21 differentially expressed proteins in the cancerous tissues in comparison to the nontumorous tissues. There were five markedly increased proteins (beta-tropomyosin, tropomyosin 1 alpha isoform b, S100 calcium binding protein A9, and an unknown protein and 16 markedly decreased proteins (Car1 proteins, selenium-binding protein 1, HMG-CoA synthase, thioredoxin 1, 1 Cys peroxiredoxin protein 2, Fcgbp protein, Cytochrome c oxidase, subunit Va, ETHE1 protein, and 7 unknown proteins. Conclusions: There were 21 differentially expressed proteins in the cancerous tissues of the mice that received AOM and DSS. Their functions include metabolism, the antioxidant system, oxidative stress, mucin production, and inflammation. These findings may provide new insights into the mechanisms of inflammation-related colon carcinogenesis and the establishment of novel therapies and preventative strategies to treat carcinogenesis in the inflamed colon.

Uptake, retention and organ/tissue distribution of 137Cs by Japanese catfish (Silurus asotus Linnaeus)

International Nuclear Information System (INIS)

Malek, M.A.; Nakahara, M.; Nakamura, R.

2004-01-01

The work describes the uptake, retention/biological elimination and organ/tissue distribution of 137 Cs by freshwater Japanese catfish (Silurus asotus Linnaeus) under laboratory conditions. The fish were divided into three groups based on their size and age and reared in 137 Cs-spiked water. The concentration of 137 Cs in the whole body of the live fish was measured at regular intervals up to 60 days. A significant accumulation of 137 Cs was found, but a steady state condition was not achieved by the end of the experiment. The bioaccumulation factors at steady state and the required time to reach steady state were estimated to be 1.55 and 255 days, 1.76 and 180 days and 1.99 and 160 days for large, medium and small size fish, respectively. To determine the effective half-life of 137 Cs, the fish were transferred and reared in the non-contaminated host water. The concentration of the remaining 137 Cs in the whole body of the live fish was measured up to 66 days. The average effective half-life of 137 Cs in the fish species was found to be ∼142 days for fish of all sizes. The distribution of 137 Cs in different organs/tissues of the fish was determined. Accumulation of 137 Cs in muscle/flesh of the fish was found to be ∼75% of whole body accumulation. The uptake rate and the retention capability of juvenile fish were found to be higher and therefore, these were more susceptible to 137 Cs than adult and old fish, and could be an important source of 137 Cs in the human food chain

De novo reconstitution of a functional mammalian urinary bladder by tissue engineering.

Science.gov (United States)

Oberpenning, F; Meng, J; Yoo, J J; Atala, A

1999-02-01

Human organ replacement is limited by a donor shortage, problems with tissue compatibility, and rejection. Creation of an organ with autologous tissue would be advantageous. In this study, transplantable urinary bladder neo-organs were reproducibly created in vitro from urothelial and smooth muscle cells grown in culture from canine native bladder biopsies and seeded onto preformed bladder-shaped polymers. The native bladders were subsequently excised from canine donors and replaced with the tissue-engineered neo-organs. In functional evaluations for up to 11 months, the bladder neo-organs demonstrated a normal capacity to retain urine, normal elastic properties, and histologic architecture. This study demonstrates, for the first time, that successful reconstitution of an autonomous hollow organ is possible using tissue-engineering methods.

Bioprinted 3D Primary Liver Tissues Allow Assessment of Organ-Level Response to Clinical Drug Induced Toxicity In Vitro.

Directory of Open Access Journals (Sweden)

Deborah G Nguyen

Full Text Available Modeling clinically relevant tissue responses using cell models poses a significant challenge for drug development, in particular for drug induced liver injury (DILI. This is mainly because existing liver models lack longevity and tissue-level complexity which limits their utility in predictive toxicology. In this study, we established and characterized novel bioprinted human liver tissue mimetics comprised of patient-derived hepatocytes and non-parenchymal cells in a defined architecture. Scaffold-free assembly of different cell types in an in vivo-relevant architecture allowed for histologic analysis that revealed distinct intercellular hepatocyte junctions, CD31+ endothelial networks, and desmin positive, smooth muscle actin negative quiescent stellates. Unlike what was seen in 2D hepatocyte cultures, the tissues maintained levels of ATP, Albumin as well as expression and drug-induced enzyme activity of Cytochrome P450s over 4 weeks in culture. To assess the ability of the 3D liver cultures to model tissue-level DILI, dose responses of Trovafloxacin, a drug whose hepatotoxic potential could not be assessed by standard pre-clinical models, were compared to the structurally related non-toxic drug Levofloxacin. Trovafloxacin induced significant, dose-dependent toxicity at clinically relevant doses (≤ 4uM. Interestingly, Trovafloxacin toxicity was observed without lipopolysaccharide stimulation and in the absence of resident macrophages in contrast to earlier reports. Together, these results demonstrate that 3D bioprinted liver tissues can both effectively model DILI and distinguish between highly related compounds with differential profile. Thus, the combination of patient-derived primary cells with bioprinting technology here for the first time demonstrates superior performance in terms of mimicking human drug response in a known target organ at the tissue level.

The Hippo pathway: key interaction and catalytic domains in organ growth control, stem cell self-renewal and tissue regeneration.

Science.gov (United States)

Cherrett, Claire; Furutani-Seiki, Makoto; Bagby, Stefan

2012-01-01

The Hippo pathway is a conserved pathway that interconnects with several other pathways to regulate organ growth, tissue homoeostasis and regeneration, and stem cell self-renewal. This pathway is unique in its capacity to orchestrate multiple processes, from sensing to execution, necessary for organ expansion. Activation of the Hippo pathway core kinase cassette leads to cytoplasmic sequestration of the nuclear effectors YAP (Yes-associated protein) and TAZ (transcriptional coactivator with PDZ-binding motif), consequently disabling their transcriptional co-activation function. Components upstream of the core kinase cassette have not been well understood, especially in vertebrates, but are gradually being elucidated and include cell polarity and cell adhesion proteins.

Cell and Tissue Engineering

CERN Document Server

2012-01-01

“Cell and Tissue Engineering” introduces the principles and new approaches in cell and tissue engineering. It includes both the fundamentals and the current trends in cell and tissue engineering, in a way useful both to a novice and an expert in the field. The book is composed of 13 chapters all of which are written by the leading experts. It is organized to gradually assemble an insight in cell and tissue function starting form a molecular nano-level, extending to a cellular micro-level and finishing at the tissue macro-level. In specific, biological, physiological, biophysical, biochemical, medical, and engineering aspects are covered from the standpoint of the development of functional substitutes of biological tissues for potential clinical use. Topics in the area of cell engineering include cell membrane biophysics, structure and function of the cytoskeleton, cell-extracellular matrix interactions, and mechanotransduction. In the area of tissue engineering the focus is on the in vitro cultivation of ...

Tissues Use Resident Dendritic Cells and Macrophages to Maintain Homeostasis and to Regain Homeostasis upon Tissue Injury: The Immunoregulatory Role of Changing Tissue Environments

Science.gov (United States)

Lech, Maciej; Gröbmayr, Regina; Weidenbusch, Marc; Anders, Hans-Joachim

2012-01-01

Most tissues harbor resident mononuclear phagocytes, that is, dendritic cells and macrophages. A classification that sufficiently covers their phenotypic heterogeneity and plasticity during homeostasis and disease does not yet exist because cell culture-based phenotypes often do not match those found in vivo. The plasticity of mononuclear phagocytes becomes obvious during dynamic or complex disease processes. Different data interpretation also originates from different conceptual perspectives. An immune-centric view assumes that a particular priming of phagocytes then causes a particular type of pathology in target tissues, conceptually similar to antigen-specific T-cell priming. A tissue-centric view assumes that changing tissue microenvironments shape the phenotypes of their resident and infiltrating mononuclear phagocytes to fulfill the tissue's need to maintain or regain homeostasis. Here we discuss the latter concept, for example, why different organs host different types of mononuclear phagocytes during homeostasis. We further discuss how injuries alter tissue environments and how this primes mononuclear phagocytes to enforce this particular environment, for example, to support host defense and pathogen clearance, to support the resolution of inflammation, to support epithelial and mesenchymal healing, and to support the resolution of fibrosis to the smallest possible scar. Thus, organ- and disease phase-specific microenvironments determine macrophage and dendritic cell heterogeneity in a temporal and spatial manner, which assures their support to maintain and regain homeostasis in whatever condition. Mononuclear phagocytes contributions to tissue pathologies relate to their central roles in orchestrating all stages of host defense and wound healing, which often become maladaptive processes, especially in sterile and/or diffuse tissue injuries. PMID:23251037

Tissue-electronics interfaces: from implantable devices to engineered tissues

Science.gov (United States)

Feiner, Ron; Dvir, Tal

2018-01-01

Biomedical electronic devices are interfaced with the human body to extract precise medical data and to interfere with tissue function by providing electrical stimuli. In this Review, we outline physiologically and pathologically relevant tissue properties and processes that are important for designing implantable electronic devices. We summarize design principles for flexible and stretchable electronics that adapt to the mechanics of soft tissues, such as those including conducting polymers, liquid metal alloys, metallic buckling and meandering architectures. We further discuss technologies for inserting devices into the body in a minimally invasive manner and for eliminating them without further intervention. Finally, we introduce the concept of integrating electronic devices with biomaterials and cells, and we envision how such technologies may lead to the development of bionic organs for regenerative medicine.

Textile Technologies and Tissue Engineering: A Path Towards Organ Weaving

OpenAIRE

Akbari, Mohsen; Tamayol, Ali; Bagherifard, Sara; Serex, Ludovic; Mostafalu, Pooria; Faramarzi, Negar; Mohammadi, Mohammad Hossein; Khademhosseini, Ali

2016-01-01

Textile technologies have recently attracted great attention as potential biofabrication tools for engineering tissue constructs. Using current textile technologies, fibrous structures can be designed and engineered to attain the required properties that are demanded by different tissue engineering applications. Several key parameters such as physiochemical characteristics of fibers, pore size and mechanical properties of the fabrics play important role in the effective use of textile technol...

[Local impact of antiseptic medical textile on tissues of organism].

Science.gov (United States)

Nazarchuk, O A; Vernyhorods'kyĭ, S V; Paliĭ, V H; Nazarchuk, H H; Paliĭ, D V; Honchar, O O; Zadereĭ, N V

2013-07-01

Morphological investigation for studying of a local impact on the tissues, localized in the antiseptic textile implantation zone, was conducted. The textile was impregnated by composition of decametoxine with modified polysaccharides. Basing on the investigation result there was established the absence of a toxic impact of antiseptic medical textile on the macroorganism tissues, the regenerative processes course, the wounds epithelization, antioedematous and anti-inflammatory effects.

Development of tissue bank

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R P Narayan

2012-01-01

Full Text Available The history of tissue banking is as old as the use of skin grafting for resurfacing of burn wounds. Beneficial effects of tissue grafts led to wide spread use of auto and allograft for management of varied clinical conditions like skin wounds, bone defects following trauma or tumor ablation. Availability of adequate amount of tissues at the time of requirement was the biggest challenge that forced clinicians to find out techniques to preserve the living tissue for prolonged period of time for later use and thus the foundation of tissue banking was started in early twentieth century. Harvesting, processing, storage and transportation of human tissues for clinical use is the major activity of tissue banks. Low temperature storage of processed tissue is the best preservation technique at present. Tissue banking organization is a very complex system and needs high technical expertise and skilled personnel for proper functioning in a dedicated facility. A small lapse/deviation from the established protocol leads to loss of precious tissues and or harm to recipients as well as the risk of transmission of deadly diseases and tumors. Strict tissue transplant acts and stringent regulations help to streamline the whole process of tissue banking safe for recipients and to community as whole.

Is There a Relationship Between Pelvic Organ Prolapse and Tissue Fibrillin-1 Levels?

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Ayla Eser

2015-09-01

Full Text Available Purpose: Pelvic organ prolapse is a multifactorial disorder in which extracellular matrix defects are implicated. Fibrillin-1 level is reduced in stress urinary incontinence. In Marfan syndrome, which is associated with mutations in Fibrillin-1, pelvic floor disorders are commonly observed. We hypothesize that Fibrillin-1 gene expression is altered in pelvic organ prolapse. Methods: Thirty women undergoing colporrhaphy or hysterectomy because of cystocele, rectocele, cystorectocele, or uterine prolapse were assigned to a pelvic prolapse study group, and thirty women undergone hysterectomy for nonpelvic prolapse conditions were assigned to a control group. Real-time polymerase chain reaction was conducted on vaginal tissue samples to measure the expression of Fibrillin-1. Expression levels were compared between study and control groups by Mann-Whitney U test with Bonferroni revision. Results: Fibrillin-1 gene expression was not significantly lower in the study group than in the control group. Similarly, no significant correlation between Fibrillin-1 levels and grade of pelvic prolapse was found. Age over 40 years (P=0.018 and menopause (P=0.027 were both associated with reduced Fibrillin-1 levels in the pelvic prolapse group, whereas the delivery of babies weighing over 3,500 g at birth was associated with increased Fibrillin-1 expression (P=0.006. Conclusions: The results did not indicate a significant reduction in Fibrillin-1 gene expression in pelvic prolapse disorders; however, reduced Fibrillin-1 may contribute to increased pelvic organ prolapse risk with age and menopause. Increased Fibrillin-1 gene expression may be a compensatory mechanism in cases of delivery of babies with high birth weight. Further studies are needed for a better understanding of these observations.

The role of mechanical loading in ligament tissue engineering.

Science.gov (United States)

Benhardt, Hugh A; Cosgriff-Hernandez, Elizabeth M

2009-12-01

Tissue-engineered ligaments have received growing interest as a promising alternative for ligament reconstruction when traditional transplants are unavailable or fail. Mechanical stimulation was recently identified as a critical component in engineering load-bearing tissues. It is well established that living tissue responds to altered loads through endogenous changes in cellular behavior, tissue organization, and bulk mechanical properties. Without the appropriate biomechanical cues, new tissue formation lacks the necessary collagenous organization and alignment for sufficient load-bearing capacity. Therefore, tissue engineers utilize mechanical conditioning to guide tissue remodeling and improve the performance of ligament grafts. This review provides a comparative analysis of the response of ligament and tendon fibroblasts to mechanical loading in current bioreactor studies. The differential effect of mechanical stimulation on cellular processes such as protease production, matrix protein synthesis, and cell proliferation is examined in the context of tissue engineering design.

Control of Scar Tissue Formation in the Cornea: Strategies in Clinical and Corneal Tissue Engineering

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Samantha L. Wilson

2012-09-01

Full Text Available Corneal structure is highly organized and unified in architecture with structural and functional integration which mediates transparency and vision. Disease and injury are the second most common cause of blindness affecting over 10 million people worldwide. Ninety percent of blindness is permanent due to scarring and vascularization. Scarring caused via fibrotic cellular responses, heals the tissue, but fails to restore transparency. Controlling keratocyte activation and differentiation are key for the inhibition and prevention of fibrosis. Ophthalmic surgery techniques are continually developing to preserve and restore vision but corneal regression and scarring are often detrimental side effects and long term continuous follow up studies are lacking or discouraging. Appropriate corneal models may lead to a reduced need for corneal transplantation as presently there are insufficient numbers or suitable tissue to meet demand. Synthetic optical materials are under development for keratoprothesis although clinical use is limited due to implantation complications and high rejection rates. Tissue engineered corneas offer an alternative which more closely mimic the morphological, physiological and biomechanical properties of native corneas. However, replication of the native collagen fiber organization and retaining the phenotype of stromal cells which prevent scar-like tissue formation remains a challenge. Careful manipulation of culture environments are under investigation to determine a suitable environment that simulates native ECM organization and stimulates keratocyte migration and generation.

Geometric triangular chiral hexagon crystal-like complexes organization in pathological tissues biological collision order.

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Jairo A Díaz

Full Text Available The present study describes and documents self-assembly of geometric triangular chiral hexagon crystal like complex organizations (GTCHC in human pathological tissues. The authors have found this architectural geometric expression at macroscopic and microscopic levels mainly in cancer processes. This study is based essentially on macroscopic and histopathologic analyses of 3000 surgical specimens: 2600 inflammatory lesions and 400 malignant tumours. Geometric complexes identified photographically at macroscopic level were located in the gross surgical specimen, and these areas were carefully dissected. Samples were taken to carry out histologic analysis. Based on the hypothesis of a collision genesis mechanism and because it is difficult to carry out an appropriate methodological observation in biological systems, the authors designed a model base on other dynamic systems to obtain indirect information in which a strong white flash wave light discharge, generated by an electronic device, hits over the lines of electrical conductance structured in helicoidal pattern. In their experimental model, the authors were able to reproduce and to predict polarity, chirality, helicoid geometry, triangular and hexagonal clusters through electromagnetic sequential collisions. They determined that similar events among constituents of extracelular matrix which drive and produce piezoelectric activity are responsible for the genesis of GTCHC complexes in pathological tissues. This research suggests that molecular crystals represented by triangular chiral hexagons derived from a collision-attraction event against collagen type I fibrils emerge at microscopic and macroscopic scales presenting a lateral assembly of each side of hypertrophy helicoid fibers, that represent energy flow in cooperative hierarchically chiral electromagnetic interaction in pathological tissues and arises as a geometry of the equilibrium in perturbed biological systems. Further

Geometric triangular chiral hexagon crystal-like complexes organization in pathological tissues biological collision order.

Science.gov (United States)

Díaz, Jairo A; Jaramillo, Natalia A; Murillo, Mauricio F

2007-12-12

The present study describes and documents self-assembly of geometric triangular chiral hexagon crystal like complex organizations (GTCHC) in human pathological tissues. The authors have found this architectural geometric expression at macroscopic and microscopic levels mainly in cancer processes. This study is based essentially on macroscopic and histopathologic analyses of 3000 surgical specimens: 2600 inflammatory lesions and 400 malignant tumours. Geometric complexes identified photographically at macroscopic level were located in the gross surgical specimen, and these areas were carefully dissected. Samples were taken to carry out histologic analysis. Based on the hypothesis of a collision genesis mechanism and because it is difficult to carry out an appropriate methodological observation in biological systems, the authors designed a model base on other dynamic systems to obtain indirect information in which a strong white flash wave light discharge, generated by an electronic device, hits over the lines of electrical conductance structured in helicoidal pattern. In their experimental model, the authors were able to reproduce and to predict polarity, chirality, helicoid geometry, triangular and hexagonal clusters through electromagnetic sequential collisions. They determined that similar events among constituents of extracelular matrix which drive and produce piezoelectric activity are responsible for the genesis of GTCHC complexes in pathological tissues. This research suggests that molecular crystals represented by triangular chiral hexagons derived from a collision-attraction event against collagen type I fibrils emerge at microscopic and macroscopic scales presenting a lateral assembly of each side of hypertrophy helicoid fibers, that represent energy flow in cooperative hierarchically chiral electromagnetic interaction in pathological tissues and arises as a geometry of the equilibrium in perturbed biological systems. Further interdisciplinary studies must

Interactions of cadmium with copper, zinc, and iron in different organs and tissues of the rat

Energy Technology Data Exchange (ETDEWEB)

Julshamn, K.; Utne, F.; Brackkan, O.R.

1977-01-01

The effect of cadmium on tissue concentrations of iron, zinc and copper was studied in male rats. Two littermate groups were fed a stock diet with or without a supplement of 100 ..mu..g cadmium per g. Every three weeks ten animals from each group were sampled and the liver, kidneys, heart, lungs, spleen, testes, muscle, fur, feces and urine were individually analyzed. Except for the fur, all the other organs showed highly significantly increased levels of cadmium when compared with the control group. The iron levels were significantly depressed in all organs. As the content in the feces remained unchanged and the urinary excretion showed an increase, it could be concluded that the cadmium supplementation resulted in a depletion of the body stores of iron. The zinc levels showed a significant increase in the liver and testes and a correspondingly significant decrease in the spleen. The levels of copper generally showed no significant changes.

Epithelial-mesenchymal transition: An emerging target in tissue fibrosis

Science.gov (United States)

Li, Meirong; Luan, Fuxin; Zhao, Yali; Hao, Haojie; Zhou, Yong; Han, Weidong

2016-01-01

Epithelial-mesenchymal transition (EMT) is involved in a variety of tissue fibroses. Fibroblasts/myofibroblasts derived from epithelial cells contribute to the excessive accumulation of fibrous connective tissue in damaged tissue, which can lead to permanent scarring or organ malfunction. Therefore, EMT-related fibrosis cannot be neglected. This review highlights the findings that demonstrate the EMT to be a direct contributor to the fibroblast/myofibroblast population in the development of tissue fibrosis and helps to elucidate EMT-related anti-fibrotic strategies, which may enable the development of therapeutic interventions to suppress EMT and potentially reverse organ fibrosis. PMID:26361988

Tissue and plasma enzyme activities in juvenile green iguanas.

Science.gov (United States)

Wagner, R A; Wetzel, R

1999-02-01

To determine activities of intracellular enzymes in 8 major organs in juvenile green iguanas and to compare tissue and plasma activities. 6 green iguanas iguanas, but high values may not always indicate overt muscle disease. The AMS activity may be specific for the pancreas, but the wide range of plasma activity would likely limit its diagnostic usefulness. Activities of AST and LDH may reflect tissue damage or inflammation, but probably do not reflect damage to specific tissues or organs.

Effect of ionizing radiations on connective tissue

International Nuclear Information System (INIS)

Altman, K.I.; Gerber, G.B.

1980-01-01

The effects of ionizing radiations on connective tissue in lung, heart, vasculature, kidney, skin, and skeletal tissues are reviewed. Special emphasis is given to the effect of ionizing radiations on vasculo-connective tissue and fibrotic changes following radiation-induced injury to organs and tissues. In order to put the subject matter in proper prospective, the general biochemistry, physiology, and pathology of connective tissue is reviewed briefly together with the participation of connective tissue in disease. The review closes with an assessment of future problems and an enumeration and discussion of important, as yet unanswered questions

CELLULAR CONTROL OF CONNECTIVE TISSUE MATRIX TENSION†

OpenAIRE

Langevin, Helene M.; Nedergaard, Maiken; Howe, Alan

2013-01-01

The biomechanical behavior of connective tissue in response to stretching is generally attributed to the molecular composition and organization of its extracellular matrix. It also is becoming apparent that fibroblasts play an active role in regulating connective tissue tension. In response to static stretching of the tissue, fibroblasts expand within minutes by actively remodeling their cytoskeleton. This dynamic change in fibroblast shape contributes to the drop in tissue tension that occur...

Artificial engineering of secondary lymphoid organs.

Science.gov (United States)

Tan, Jonathan K H; Watanabe, Takeshi

2010-01-01

Secondary lymphoid organs such as spleen and lymph nodes are highly organized immune structures essential for the initiation of immune responses. They display distinct B cell and T cell compartments associated with specific stromal follicular dendritic cells and fibroblastic reticular cells, respectively. Interweaved through the parenchyma is a conduit system that distributes small antigens and chemokines directly to B and T cell zones. While most structural aspects between lymph nodes and spleen are common, the entry of lymphocytes, antigen-presenting cells, and antigen into lymphoid tissues is regulated differently, reflecting the specialized functions of each organ in filtering either lymph or blood. The overall organization of lymphoid tissue is vital for effective antigen screening and recognition, and is a feature which artificially constructed lymphoid organoids endeavor to replicate. Synthesis of artificial lymphoid tissues is an emerging field that aims to provide therapeutic application for the treatment of severe infection, cancer, and age-related involution of secondary lymphoid tissues. The development of murine artificial lymphoid tissues has benefited greatly from an understanding of organogenesis of lymphoid organs, which has delineated cellular and molecular elements essential for the recruitment and organization of lymphocytes into lymphoid structures. Here, the field of artificial lymphoid tissue engineering is considered including elements of lymphoid structure and development relevant to organoid synthesis. (c) 2010 Elsevier Inc. All rights reserved.

Creating biomaterials with spatially organized functionality.

Science.gov (United States)

Chow, Lesley W; Fischer, Jacob F

2016-05-01

Biomaterials for tissue engineering provide scaffolds to support cells and guide tissue regeneration. Despite significant advances in biomaterials design and fabrication techniques, engineered tissue constructs remain functionally inferior to native tissues. This is largely due to the inability to recreate the complex and dynamic hierarchical organization of the extracellular matrix components, which is intimately linked to a tissue's biological function. This review discusses current state-of-the-art strategies to control the spatial presentation of physical and biochemical cues within a biomaterial to recapitulate native tissue organization and function. © 2016 by the Society for Experimental Biology and Medicine.

Pairing experimentation and computational modelling to understand the role of tissue inducer cells in the development of lymphoid organs

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Kieran eAlden

2012-07-01

Full Text Available The use of genetic tools, imaging technologies and ex vivo culture systems has provided significant insights into the role of tissue inducer cells and associated signalling pathways in the formation and function of lymphoid organs. Despite advances in experimental technologies, the molecular and cellular process orchestrating the formation of a complex 3-dimensional tissue is difficult to dissect using current approaches. Therefore, a robust set of simulation tools have been developed to model the processes involved in lymphoid tissue development. Specifically the role of different tissue inducer cell populations in the dynamic formation of Peyer's Patches has been examined. Utilising approaches from critical systems engineering an unbiased model of lymphoid tissue inducer cell function has been developed, that permits the development of emerging behaviours that are statistically not different from that observed in vivo. These results provide the confidence to utilise statistical methods to explore how the simulator predicts cellular behaviour and outcomes under different physiological conditions. Such methods, known as sensitivity analysis techniques, can provide insight into when a component part of the system (such as a particular cell type, adhesion molecule, or chemokine begins to have an influence on observed behaviour, and quantifies the effect a component part has on the end result: the formation of lymphoid tissue. Through use of such a principled approach in the design, calibration, and analysis of a computer simulation, a robust in silico tool can be developed which can both further the understanding of a biological system being explored, and act as a tool for the generation of hypotheses which can be tested utilising experimental approaches.

Nanoreinforced Hydrogels for Tissue Engineering: Biomaterials that are Compatible with Load-Bearing and Electroactive Tissues

DEFF Research Database (Denmark)

Mehrali, Mehdi; Thakur, Ashish; Pennisi, Christian Pablo

2017-01-01

, mechanical, and electrical properties. Here, recent advances in the fabrication and application of nanocomposite hydrogels in tissue engineering applications are described, with specific attention toward skeletal and electroactive tissues, such as cardiac, nerve, bone, cartilage, and skeletal muscle......Given their highly porous nature and excellent water retention, hydrogel-based biomaterials can mimic critical properties of the native cellular environment. However, their potential to emulate the electromechanical milieu of native tissues or conform well with the curved topology of human organs...

The plant tissue culture

International Nuclear Information System (INIS)

Crocomo, O.J.; Sharp, W.R.

1973-01-01

Progress in the field of plant tissue culture at the Plant Biochemistry Sector, Centro de Energia na Agricultura (CENA), Piracicaba, S.P., Brazil, pertains to the simplification of development in 'Phaseolus vulgaris' by dividing the organism into its component organs, tissues, and cells and the maintenance of these components on defined culture media 'in vitro'. This achievement has set the stage for probing the basis for the stability of the differentiated states and/or the reentry of mature differentiated cells into the mitotic cell cycle and their subsequent redifferentiation. Data from such studies at the cytological and biochemical level have been invaluable in the elucidation of the control mechanisms responsible for expression of the cellular phenotype. Unlimited possibilities exist for the application of tissue culture in the vegetative propagation of 'Phaseolus' and other important cultivars in providing genocopies or a large scale and/or readily obtaining plantlets from haploid cell lines or from protoplast (wall-less cells) hybridization products following genetic manipulation. These tools are being applied in this laboratory for the development and selection of high protein synthesizing 'Phaseolus' cultivars

Lymphoid Tissue Grafts in Man

Energy Technology Data Exchange (ETDEWEB)

Kay, H. E.M. [Royal Marsden Hospital, Institute of Cancer Research, London (United Kingdom)

1969-07-15

Grafts of lymphoid tissue or of lymphoid stem cells may be appropriate in the treatment of some congenital immune deficiency disorders. The reasons for preferring tissues of foetal origin are discussed and the evidence for foetal immunocompetence is briefly summarized. Methods of storing foetal liver cells and cells or fragments of thymus are mentioned, and the organization of the Foetal Tissue Bank of the Royal Marsden Hospital is described. Clinical data from transplantation of lymphoid cells in various immune deficiency disorders are briefly presented. (author)

Morphology of mucosa-associated lymphoid tissue in odontocetes.

Science.gov (United States)

Silva, Fernanda M O; Guimarães, Juliana P; Vergara-Parente, Jociery E; Carvalho, Vitor L; Carolina, Ana; Meirelles, O; Marmontel, Miriam; Oliveira, Bruno S S P; Santos, Silvanise M; Becegato, Estella Z; Evangelista, Janaina S A M; Miglino, Maria Angelica

2016-09-01

This study describes the mucosa-associated lymphoid tissue (MALT) in odontocetes from the Brazilian coast and freshwater systems. Seven species were evaluated and tissue samples were analyzed by light, scanning and transmission electron microscopy, and immunohistochemistry. Laryngeal tonsil was a palpable oval mass located in the larynx, composed of a lymphoepithelial complex. Dense collections of lymphocytes were found in the skin of male fetus and calf. Clusters of lymphoid tissue were found in the uterine cervix of a reproductively active juvenile female and along the pulmonary artery of an adult female. Lymphoid tissues associated with the gastrointestinal tract were characterized by diffusely arranged or organized lymphocytes. The anal tonsil was composed of an aggregate of lymphoid tissue occurring exclusively in the anal canal, being composed of squamous epithelium branches. MALT was present in different tissues and organic systems of cetaceans, providing constant protection against mucosal pathogens present in their environment. © 2016 Wiley Periodicals, Inc.

Selected organic compounds and trace elements in streambed sediments and fish tissues, Cook Inlet Basin, Alaska

Science.gov (United States)

Frenzel, Steven A.

2000-01-01

Organochlorines, semivolatile organic compounds (SVOCs), and trace elements were investigated in streambed sediments and fish tissues at selected sites in the Cook Inlet Basin, Alaska, during 1998. At most sites, SVOCs and organochlorine compounds were either not detected or detected at very low concentrations. Chester Creek at Arctic Boulevard at Anchorage, which was the only site sampled with a significant degree of development in the watershed, had elevated levels of many SVOCs in streambed sediment. Coring of sediments from two ponds on Chester Creek confirmed the presence of elevated concentrations of a variety of organic compounds. Moose Creek, a stream with extensive coal deposits in its watershed, had low concentrations of numerous SVOCs in streambed sediment. Three sites located in national parks or in a national wildlife refuge had no detectable concentrations of SVOCs. Trace elements were analyzed in both streambed sediments and tissues of slimy sculpin. The two media provided similar evidence for elevated concentrations of cadmium, lead, and zinc at Chester Creek. In this study, 'probable effect levels '(PELs) were determined from sediments finer than 0.063 millimeters, where concentrations tend to be greatest. Arsenic and chromium concentrations exceeded the PEL at eight and six sites respectively. Zinc exceeded the PEL at one site. Cadmium and copper concentrations were smaller than the PEL at all sites. Mercury concentrations in streambed sediments from the Deshka River were near the PEL, and selenium concentrations at that site also appear to be elevated above background levels. At half the sites where slimy sculpin were sampled, selenium concentrations were at levels that may cause adverse effects in some species.

Synthetic Phage for Tissue Regeneration

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So Young Yoo

2014-01-01

Full Text Available Controlling structural organization and signaling motif display is of great importance to design the functional tissue regenerating materials. Synthetic phage, genetically engineered M13 bacteriophage has been recently introduced as novel tissue regeneration materials to display a high density of cell-signaling peptides on their major coat proteins for tissue regeneration purposes. Structural advantages of their long-rod shape and monodispersity can be taken together to construct nanofibrous scaffolds which support cell proliferation and differentiation as well as direct orientation of their growth in two or three dimensions. This review demonstrated how functional synthetic phage is designed and subsequently utilized for tissue regeneration that offers potential cell therapy.

Ageing combines CD4 T cell lymphopenia in secondary lymphoid organs and T cell accumulation in gut associated lymphoid tissue.

Science.gov (United States)

Martinet, Kim Zita; Bloquet, Stéphane; Bourgeois, Christine

2014-01-01

CD4 T cell lymphopenia is an important T cell defect associated to ageing. Higher susceptibility to infections, cancer, or autoimmune pathologies described in aged individuals is thought to partly rely on T cell lymphopenia. We hypothesize that such diverse effects may reflect anatomical heterogeneity of age related T cell lymphopenia. Indeed, no data are currently available on the impact of ageing on T cell pool recovered from gut associated lymphoid tissue (GALT), a crucial site of CD4 T cell accumulation. Primary, secondary and tertiary lymphoid organs of C57BL/6 animals were analysed at three intervals of ages: 2 to 6 months (young), 10 to 14 months (middle-aged) and 22 to 26 months (old). We confirmed that ageing preferentially impacted CD4 T cell compartment in secondary lymphoid organs. Importantly, a different picture emerged from gut associated mucosal sites: during ageing, CD4 T cell accumulation was progressively developing in colon and small intestine lamina propria and Peyer's patches. Similar trend was also observed in middle-aged SJL/B6 F1 mice. Interestingly, an inverse correlation was detected between CD4 T cell numbers in secondary lymphoid organs and colonic lamina propria of C57BL/6 mice whereas no increase in proliferation rate of GALT CD4 T cells was detected. In contrast to GALT, no CD4 T cell accumulation was detected in lungs and liver in middle-aged animals. Finally, the concomitant accumulation of CD4 T cell in GALT and depletion in secondary lymphoid organs during ageing was detected both in male and female animals. Our data thus demonstrate that T cell lymphopenia in secondary lymphoid organs currently associated to ageing is not sustained in gut or lung mucosa associated lymphoid tissues or non-lymphoid sites such as the liver. The inverse correlation between CD4 T cell numbers in secondary lymphoid organs and colonic lamina propria and the absence of overt proliferation in GALT suggest that marked CD4 T cell decay in secondary

Transcriptome architecture across tissues in the pig

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Folch Josep M

2008-04-01

Full Text Available Abstract Background Artificial selection has resulted in animal breeds with extreme phenotypes. As an organism is made up of many different tissues and organs, each with its own genetic programme, it is pertinent to ask: How relevant is tissue in terms of total transcriptome variability? Which are the genes most distinctly expressed between tissues? Does breed or sex equally affect the transcriptome across tissues? Results In order to gain insight on these issues, we conducted microarray expression profiling of 16 different tissues from four animals of two extreme pig breeds, Large White and Iberian, two males and two females. Mixed model analysis and neighbor – joining trees showed that tissues with similar developmental origin clustered closer than those with different embryonic origins. Often a sound biological interpretation was possible for overrepresented gene ontology categories within differentially expressed genes between groups of tissues. For instance, an excess of nervous system or muscle development genes were found among tissues of ectoderm or mesoderm origins, respectively. Tissue accounted for ~11 times more variability than sex or breed. Nevertheless, we were able to confidently identify genes with differential expression across tissues between breeds (33 genes and between sexes (19 genes. The genes primarily affected by sex were overall different than those affected by breed or tissue. Interaction with tissue can be important for differentially expressed genes between breeds but not so much for genes whose expression differ between sexes. Conclusion Embryonic development leaves an enduring footprint on the transcriptome. The interaction in gene × tissue for differentially expressed genes between breeds suggests that animal breeding has targeted differentially each tissue's transcriptome.

Microgravity cultivation of cells and tissues

Science.gov (United States)

Freed, L. E.; Pellis, N.; Searby, N.; de Luis, J.; Preda, C.; Bordonaro, J.; Vunjak-Novakovic, G.

1999-01-01

In vitro studies of cells and tissues in microgravity, either simulated by cultivation conditions on earth or actual, during spaceflight, are expected to help identify mechanisms underlying gravity sensing and transduction in biological organisms. In this paper, we review rotating bioreactor studies of engineered skeletal and cardiovascular tissues carried out in unit gravity, a four month long cartilage tissue engineering study carried out aboard the Mir Space Station, and the ongoing laboratory development and testing of a system for cell and tissue cultivation aboard the International Space Station.

Perceptions about tissue donation for medical research among ...

African Journals Online (AJOL)

Background: Tissue banking refers to a structured and organized resource collection of tissue. Recent advances in research technology and knowledge in the fields of human genetics/ genomics highlights the need to maintain a steady supply of tissue for researchers. Objective: To assess the perception and willingness of ...

AcEST: BP920976 [AcEST

Lifescience Database Archive (English)

Full Text Available 89|TPM_CHLNI Tropomyosin OS=Chlamys nipponensis akazara P... 43 6e-04 sp|Q60952|C...448 EKEASEKAQWQNEKDRINQIQQLKIDIEELKFQADRAERE 487 >sp|O02389|TPM_CHLNI Tropomyosin OS=Chlamys nipponensis akazara

Growth versus metabolic tissue replacement in mouse tissues determined by stable carbon and nitrogen isotope analysis

Science.gov (United States)

Macavoy, S. E.; Jamil, T.; Macko, S. A.; Arneson, L. S.

2003-12-01

Stable isotope analysis is becoming an extensively used tool in animal ecology. The isotopes most commonly used for analysis in terrestrial systems are those of carbon and nitrogen, due to differential carbon fractionation in C3 and C4 plants, and the approximately 3‰ enrichment in 15N per trophic level. Although isotope signatures in animal tissues presumably reflect the local food web, analysis is often complicated by differential nutrient routing and fractionation by tissues, and by the possibility that large organisms are not in isotopic equilibrium with the foods available in their immediate environment. Additionally, the rate at which organisms incorporate the isotope signature of a food through both growth and metabolic tissue replacement is largely unknown. In this study we have assessed the rate of carbon and nitrogen isotopic turnover in liver, muscle and blood in mice following a diet change. By determining growth rates, we were able to determine the proportion of tissue turnover caused by growth versus that caused by metabolic tissue replacement. Growth was found to account for approximately 10% of observed tissue turnover in sexually mature mice (Mus musculus). Blood carbon was found to have the shortest half-life (16.9 days), followed by muscle (24.7 days). Liver carbon turnover was not as well described by the exponential decay equations as other tissues. However, substantial liver carbon turnover was observed by the 28th day after diet switch. Surprisingly, these tissues primarily reflect the carbon signature of the protein, rather than carbohydrate, source in their diet. The nitrogen signature in all tissues was enriched by 3 - 5‰ over their dietary protein source, depending on tissue type, and the isotopic turnover rates were comparable to those observed in carbon.

Mid-term function and remodeling potential of tissue engineered tricuspid valve

DEFF Research Database (Denmark)

Ropcke, Diana M; Rasmussen, Jonas; Ilkjær, Christine

2018-01-01

. CONCLUSIONS: ECM tricuspid tube grafts were stronger than native leaflet tissue. Histologically, the acellular ECM tube grafts showed evidence of constructive tissue remodeling with endothelialization and connective tissue organization. These findings support the concept of tissue engineering...... at implantation (baseline) compared to native leaflet tissue (0.3 ± 0.02 mg/mm3vs. 0.1 ± 0.03 mg/mm3, p ...). Histologically, ECM valves showed endothelialization, host cell infiltration and structural collagen organization together with elastin generation after six months, indicating tissue remodeling and -engineering together with gradual development of a close-to-native leaflet structure without foreign body response...

Emerging roles of the neurotrophin receptor TrkC in synapse organization.

Science.gov (United States)

Naito, Yusuke; Lee, Alfred Kihoon; Takahashi, Hideto

2017-03-01

Tropomyosin-receptor-kinase (Trk) receptors have been extensively studied for their roles in kinase-dependent signaling cascades in nervous system development. Synapse organization is coordinated by trans-synaptic interactions of various cell adhesion proteins, a representative example of which is the neurexin-neuroligin complex. Recently, a novel role for TrkC as a synapse organizing protein has been established. Post-synaptic TrkC binds to pre-synaptic type-IIa receptor-type protein tyrosine phosphatase sigma (PTPσ). TrkC-PTPσ specifically induces excitatory synapses in a kinase domain-independent manner. TrkC has distinct extracellular domains for PTPσ- and NT-3-binding and thus may bind both ligands simultaneously. Indeed, NT-3 enhances the TrkC-PTPσ interaction, thus facilitating synapse induction at the pre-synaptic side and increasing pre-synaptic vesicle recycling in a kinase-independent fashion. A crystal structure study has revealed the detailed structure of the TrkC-PTPσ complex as well as competitive modulation of TrkC-mediated synaptogenesis by heparan sulfate proteoglycans (HSPGs), which bind the same domain of TrkC as PTPσ. Thus, there is strong evidence supporting a role for the TrkC-PTPσ complex in mechanisms underlying the fine turning of neural connectivity. Furthermore, disruption of the TrkC-PTPσ complex may be the underlying cause of certain psychiatric disorders caused by mutations in the gene encoding TrkC (NTRK3), supporting its role in cognitive functions. Copyright © 2016 Elsevier Ireland Ltd and Japan Neuroscience Society. All rights reserved.

Crosslinkable Hydrogels Derived from Cartilage, Meniscus, and Tendon Tissue

NARCIS (Netherlands)

Visser, Jetze; Levett, Peter A.; te Moller, Nikae C. R.; Besems, Jeremy; Boere, Kristel W. M.; van Rijen, Mattie H. P.; de Grauw, Janny C.; Dhert, Wouter J. A.; van Weeren, P. Rene; Malda, J

2015-01-01

Decellularized tissues have proven to be versatile matrices for the engineering of tissues and organs. These matrices usually consist of collagens, matrix-specific proteins, and a set of largely undefined growth factors and signaling molecules. Although several decellularized tissues have found

[Biofabrication: new approaches for tissue regeneration].

Science.gov (United States)

Horch, Raymund E; Weigand, Annika; Wajant, Harald; Groll, Jürgen; Boccaccini, Aldo R; Arkudas, Andreas

2018-04-01

The advent of Tissue Engineering (TE) in the early 1990ies was fostered by the increasing need for functional tissue and organ replacement. Classical TE was based on the combination of carrier matrices, cells and growth factors to reconstitute lost or damaged tissue and organs. Despite considerable results in vitro and in experimental settings the lack of early vascularization has hampered its translation into daily clinical practice so far. A new field of research, called "biofabrication" utilizing latest 3D printing technologies aims at hierarchically and spatially incorporating different cells, biomaterials and molecules into a matrix to alleviate a directed maturation of artificial tissue. A literature research of the relevant publications regarding biofabrication and bioprinting was performed using the PubMed data base. Relevant papers were selected and evaluated with secondary analysis of specific citations on the bioprinting techniques. 180 relevant papers containing the key words were identified and evaluated. Basic principles into the developing field of bioprinting technology could be discerned. Key elements comprise the high-throughput assembly of cells and the fabrication of complex and functional hierarchically organized tissue constructs. Five relevant technological principles for bioprinting were identified, such as stereolithography, extrusion-based printing, laser-assisted printing, inkjet-based printing and nano-bioprinting. The different technical methods of 3D printing were found to be associated with various positive but also negative effects on cells and proteins during the printing process. Research efforts in this field obviously aim towards the development of optimizing the so called bioinks and the printing technologies. This review details the evolution of the classical methods of TE in Regenerative Medicine into the evolving field of biofabrication by bioprinting. The advantages of 3D bioprinting over traditional tissue engineering

Fabrication of scaffolds in tissue engineering: A review

Science.gov (United States)

Zhao, Peng; Gu, Haibing; Mi, Haoyang; Rao, Chengchen; Fu, Jianzhong; Turng, Lih-sheng

2018-03-01

Tissue engineering (TE) is an integrated discipline that involves engineering and natural science in the development of biological materials to replace, repair, and improve the function of diseased or missing tissues. Traditional medical and surgical treatments have been reported to have side effects on patients caused by organ necrosis and tissue loss. However, engineered tissues and organs provide a new way to cure specific diseases. Scaffold fabrication is an important step in the TE process. This paper summarizes and reviews the widely used scaffold fabrication methods, including conventional methods, electrospinning, three-dimensional printing, and a combination of molding techniques. Furthermore, the differences among the properties of tissues, such as pore size and distribution, porosity, structure, and mechanical properties, are elucidated and critically reviewed. Some studies that combine two or more methods are also reviewed. Finally, this paper provides some guidance and suggestions for the future of scaffold fabrication.

Comparative study of radiosensitivity of normal and regenerating tissues

International Nuclear Information System (INIS)

Samokhvalova, H.S.; Popova, M.F.

1983-01-01

A comparative study of radiosensitivity of cells of normal and regenerating tissues of bone marrow and spleen has demonstrated that single exposure to X-rays produces a lesser damaging effect on regenerating tissues than on normal ones. The data obtained indicate that the increase in radioresistance of the organism during active regeneration of the haemopoietic organs is due not merely to the increase in the dividing cell pool of these organs but also to qualitative changes in their functional state

Development of multilayer constructs for tissue engineering

NARCIS (Netherlands)

Bettahalli, N. M. S.; Groen, N.; Steg, H.; Unadkat, H.; de Boer, J.; van Blitterswijk, C. A.; Wessling, M.; Stamatialis, D.

The rapidly developing field of tissue engineering produces living substitutes that restore, maintain or improve the function of tissues or organs. In contrast to standard therapies, the engineered products become integrated within the patient, affording a potentially permanent and specific cure of

Development of multilayer constructs for tissue engineering

NARCIS (Netherlands)

Bettahalli Narasimha, M.S.; Groen, N.; Steg, H.; Unadkat, H.V.; de Boer, Jan; van Blitterswijk, Clemens; Wessling, Matthias; Stamatialis, Dimitrios

2014-01-01

The rapidly developing field of tissue engineering produces living substitutes that restore, maintain or improve the function of tissues or organs. In contrast to standard therapies, the engineered products become integrated within the patient, affording a potentially permanent and specific cure of

Peripheral tissue oximetry

DEFF Research Database (Denmark)

Hyttel-Sorensen, Simon; Hessel, Trine Witzner; Greisen, Gorm

2014-01-01

Estimation of regional tissue oxygenation (rStO2) by near infrared spectroscopy enables non-invasive end-organ oxygen balance monitoring and could be a valuable tool in intensive care. However, the diverse absolute values and dynamics of different devices, and overall poor repeatability of measur......Estimation of regional tissue oxygenation (rStO2) by near infrared spectroscopy enables non-invasive end-organ oxygen balance monitoring and could be a valuable tool in intensive care. However, the diverse absolute values and dynamics of different devices, and overall poor repeatability......, and response to changing oxygenation by the down slope of rStO2 during vascular occlusion in the respective arm. 10 healthy adults, 21-29 years old, with double skinfolds on the forearm less than 10 mm participated. The median rStO2 was 70.7% (interquartile range (IQR) 7.7%), 68.4% (IQR 8.4%), and 64.6% (IQR 4...

European quality system for tissue banking.

Science.gov (United States)

Manyalich, M; Navarro, A; Koller, J; Loty, B; de Guerra, A; Cornu, O; Vabels, G; Fornasari, P M; Costa, A N; Siska, I; Hirn, M; Franz, N; Miranda, B; Kaminski, A; Uhrynowska, I; Van Baare, J; Trias, E; Fernández, C; de By, T; Poniatowski, S; Carbonell, R

2009-01-01

The aims of this project were to analyze the factors that influence quality and safety of tissues for transplantation and to develop the method to ensure standards of quality and safety in relation to tissue banking as demanded by European Directive 2004/23/EC and its technical annexes. It is organized in 4 Working Groups, the objectives of each one being focused in a specific area. The Guide of Recommendations for Tissue Banking is structured into 4 parts: (1) quality systems that apply to tissue banking and general quality system requirements, (2) regulatory framework in Europe, (3) standards available, and (4) recommendations of the fundamental quality and safety keypoints. This Working Group handled design of a multinational musculoskeletal tissue registry prototype. This Working Group handled design and validation of a specialized training model structured into online and face-to-face courses. The model was improved with suggestions from students, and 100% certification was obtained. The Guide for Auditing Tissue Establishments provides guidance for auditors, a self-assessment questionnaire, and an audit report form. The effectiveness and sustainability of the outputs were assessed. Both guides are useful for experienced tissue establishments and auditors and also for professionals that are starting in the field. The registry prototype proves it is possible to exchange tissues between establishments throughout Europe. The training model has been effective in educating staff and means having professionals with excellent expertise. Member states could adapt/adopt it. The guides should be updated periodically and perhaps a European organization should take responsibility for this and even create a body of auditors.

Regulation of actomyosin ATPase activity by troponin-tropomyosin: effect of the binding of the myosin subfragment 1 (S-1) ATP complex

International Nuclear Information System (INIS)

Greene, L.E.; Williams, D.L. Jr.; Eisenberg, E.

1987-01-01

In the authors' model of regulation, the observed lack of cooperativity in the binding of myosin subfragment 1 (S-1) with bound ATP to the troponin-tropomyosin-actin complex (regulated actin) is explained by S-1 ATP having about the same affinity for the conformation of the regulated actin that activates the myosin ATPase activity (turned-on form) and the conformation that does not activate the myosin ATPase activity (turned-off form). This predicts that, in the absence of Ca 2+ , S-1 ATP should not turn on the regulated actin filament. In the present study, they tested this prediction by using either unmodified S-1 or S-1 chemically modified with N,N'-p-phenylenedimaleimide (pPDM S-1) so that functionally it acts like S-1 ATP, although it does not hydrolyze ATP. [ 14 C]pPDM and [ 32 P]ATP were used as tracers. They found that, in the absence of Ca 2+ , neither S-1 ATP nor pPDM S-1 ATP significantly turns on the ATPase activity of the regulated complex of actin and S-1 (acto S-1). In contrast, in the presence of Ca 2+ , pPDM S-1 ATP binding almost completely turns on the regulated acto S-1 ATPase activity. These results can be explained by their original cooperativity model, with pPDM S-1 ATP binding only ≅ 2 fold more strongly to the turned-on form that to the turned-off form of regulated actin. However, the results are not consistent with our alternative model, which predicts that if pPDM S-1 ATP binds to actin in the absence of Ca 2+ but does not turn on the ATPase activity, then it should also turn on the ATPase activity in the presence of Ca 2+

Regulatory aspects of tissue donation, banking and transplantation in India.

Science.gov (United States)

Lobo Gajiwala, Astrid

2018-05-04

Amendments to India's Transplantation of Human Organs Act, 1994, have established the legality of tissue donation and transplantation from deceased donors and the conditions under which they are permitted. The amended Act, now known as The Transplantation of Human Organs and Tissues Act, 1994, seeks to prevent the commercialization of tissue donation and to guarantee the safety of indigenous allografts. Registration of tissue banks, compliance with national standards and the appointment of transplant co-ordinators in hospitals registered under the Act are now mandatory. A national registry and Regional and State networks for donation and transplantation of tissues have been introduced. Despite the amendments a few anomalies of the principal Act persist as some of the differences between tissue and organ donation and transplantation have been overlooked. These include the possibility of skin donation in locations other than hospitals; the donation of medical and surgical tissue residues which does not pose any risk to the living donor; the non-requirement for compatibility between donor and recipient; the delayed time factor between tissue donation and transplantation which makes identification of a recipient at the time of donation impossible; and the easy availability of alternatives to tissues which make waiting lists redundant for many tissues. Rules for the implementation of the amended Act were framed in 2014 but like the Act must be adopted by the State health assemblies to become universally applicable in the country.

Processing laboratory of radio sterilized biological tissues

International Nuclear Information System (INIS)

Aguirre H, Paulina; Zarate S, Herman; Silva R, Samy; Hitschfeld, Mario

2005-01-01

The nuclear development applications have also reached those areas related to health. The risk of getting contagious illnesses through applying biological tissues has been one of the paramount worries to be solved since infectious illnesses might be provoked by virus, fungis or bacterias coming from donors or whether they have been introduced by means of intermediate stages before the use of these tissues. Therefore it has been concluded that the tissue allografts must be sterilized. The sterilization of medical products has been one of the main applications of the ionizing radiations and that it is why the International Organization of Atomic Energy began in the 70s promoting works related to the biological tissue sterilization and pharmaceutical products. The development of different tissue preservation methods has made possible the creation of tissue banks in different countries, to deal with long-term preservation. In our country, a project was launched in 1998, 'Establishment of a Tissue Bank in Latino america', this project was supported by the OIEA through the project INT/ 6/ 049, and was the starting of the actual Processing Laboratory of Radioesterilized Biological Tissues (LPTR), leaded by the Chilean Nuclear Energy Commission (CCHEN). This first organization is part of a number of entities compounding the Tissue Bank in Chile, organizations such as the Transplantation Promotion Corporation hospitals and the LPTR. The working system is carried out by means of the interaction between the hospitals and the laboratory. The medical professionals perform the procuring of tissues in the hospitals, then send them to the LPTR where they are processed and sterilized with ionizing radiation. The cycle ends up with the tissues return released to the hospitals, where they are used, and then the result information is sent to the LPTR as a form of feedback. Up to now, human skin has been processed (64 donors), amniotic membranes (35 donors) and pig skin (175 portions

DNA Double-Strand Break Rejoining in Complex Normal Tissues

International Nuclear Information System (INIS)

Ruebe, Claudia E.; Dong, Xiaorong; Kuehne, Martin; Fricke, Andreas; Kaestner, Lars; Lipp, Peter; Ruebe, Christian

2008-01-01

Purpose: The clinical radiation responses of different organs vary widely and likely depend on the intrinsic radiosensitivities of their different cell populations. Double-strand breaks (DSBs) are the most deleterious form of DNA damage induced by ionizing radiation, and the cells' capacity to rejoin radiation-induced DSBs is known to affect their intrinsic radiosensitivity. To date, only little is known about the induction and processing of radiation-induced DSBs in complex normal tissues. Using an in vivo model with repair-proficient mice, the highly sensitive γH2AX immunofluorescence was established to investigate whether differences in DSB rejoining could account for the substantial differences in clinical radiosensitivity observed among normal tissues. Methods and Materials: After whole body irradiation of C57BL/6 mice (0.1, 0.5, 1.0, and 2.0 Gy), the formation and rejoining of DSBs was analyzed by enumerating γH2AX foci in various organs representative of both early-responding (small intestine) and late-responding (lung, brain, heart, kidney) tissues. Results: The linear dose correlation observed in all analyzed tissues indicated that γH2AX immunofluorescence allows for the accurate quantification of DSBs in complex organs. Strikingly, the various normal tissues exhibited identical kinetics for γH2AX foci loss, despite their clearly different clinical radiation responses. Conclusion: The identical kinetics of DSB rejoining measured in different organs suggest that tissue-specific differences in radiation responses are independent of DSB rejoining. This finding emphasizes the fundamental role of DSB repair in maintaining genomic integrity, thereby contributing to cellular viability and functionality and, thus, tissue homeostasis

Gastrointestinal Epithelial Organoid Cultures from Postsurgical Tissues.

Science.gov (United States)

Hahn, Soojung; Yoo, Jongman

2017-08-17

An organoid is a cellular structure three-dimensionally (3D) cultured from self-organizing stem cells in vitro, which has a cell population, architectures, and organ specific functions like the originating organs. Recent advances in the 3D culture of isolated intestinal crypts or gastric glands have enabled the generation of human gastrointestinal epithelial organoids. Gastrointestinal organoids recapitulate the human in vivo physiology because of all the intestinal epithelial cell types that differentiated and proliferated from tissue resident stem cells. Thus far, gastrointestinal organoids have been extensively used for generating gastrointestinal disease models. This protocol describes the method of isolating a gland or crypt using stomach or colon tissue after surgery and establishing them into gastroids or colonoids.

Micro-Organ Device

Science.gov (United States)

Gonda, Steve R. (Inventor); Chang, Robert C. (Inventor); Starly, Binil (Inventor); Culbertson, Christopher (Inventor); Holtorf, Heidi L. (Inventor); Sun, Wei (Inventor); Leslie, Julia (Inventor)

2013-01-01

A method for fabricating a micro-organ device comprises providing a microscale support having one or more microfluidic channels and one or more micro-chambers for housing a micro-organ and printing a micro-organ on the microscale support using a cell suspension in a syringe controlled by a computer-aided tissue engineering system, wherein the cell suspension comprises cells suspended in a solution containing a material that functions as a three-dimensional scaffold. The printing is performed with the computer-aided tissue engineering system according to a particular pattern. The micro-organ device comprises at least one micro-chamber each housing a micro-organ; and at least one microfluidic channel connected to the micro-chamber, wherein the micro-organ comprises cells arranged in a configuration that includes microscale spacing between portions of the cells to facilitate diffusion exchange between the cells and a medium supplied from the at least one microfluidic channel.

New aspects of fenestrated vasculature and tissue dynamics in the sensory circumventricular organs of adult brains

Directory of Open Access Journals (Sweden)

Seiji eMiyata

2015-10-01

Full Text Available The blood–brain barrier (BBB generally consists of endothelial tight junction barriers that prevent the free entry of blood-derived substances, thereby maintaining the extracellular environment of the brain. However, the circumventricular organs (CVOs, which are located along the midlines of the brain ventricles, lack these endothelial barriers and have fenestrated capillaries; therefore, they have a number of essential functions, including the transduction of information between the blood circulation and brain. Previous studies have demonstrated the extensive contribution of the CVOs to body fluid and thermal homeostasis, energy balance, the chemoreception of blood-derived substances, and neuroinflammation. In this review, recent advances have been discussed in fenestrated capillary characterization and dynamic tissue reconstruction accompanied by angiogenesis and neurogliogenesis in the sensory CVOs of adult brains. The sensory CVOs, including the organum vasculosum of the lamina terminalis (OVLT, subfornical organ (SFO, and area postrema (AP, have size-selective and heterogeneous vascular permeabilities. Astrocyte-/tanycyte-like neural stem cells (NSCs sense blood- and cerebrospinal fluid-derived information through the transient receptor potential vanilloid 1, a mechanical/osmotic receptor, Toll-like receptor 4, a lipopolysaccharide receptor, and Nax, a Na-sensing Na channel. They also express tight junction proteins and densely and tightly surround mature neurons to protect them from blood-derived neurotoxic substances, indicating that the NSCs of the CVOs perform BBB functions while maintaining the capacity to differentiate into new neurons and glial cells. In addition to neurogliogenesis, the density of fenestrated capillaries is regulated by angiogenesis, which is accompanied by the active proliferation and sprouting of endothelial cells. Vascular endothelial growth factor (VEGF signaling may be involved in angiogenesis and

Wide range of metallic and organic contaminants in various tissues of the Antarctic prion, a planktonophagous seabird from the Southern Ocean

International Nuclear Information System (INIS)

Fromant, Aymeric; Carravieri, Alice; Bustamante, Paco; Labadie, Pierre; Budzinski, Hélène; Peluhet, Laurent; Churlaud, Carine; Chastel, Olivier; Cherel, Yves

2016-01-01

ABSTRACT: Trace elements (n = 14) and persistent organic pollutants (POPs, n = 30) were measured in blood, liver, kidney, muscle and feathers of 10 Antarctic prions (Pachyptila desolata) from Kerguelen Islands, southern Indian Ocean, in order to assess their concentrations, tissue distribution, and inter-tissue and inter-contaminant relationships. Liver, kidney and feathers presented the highest burdens of arsenic, cadmium and mercury, respectively. Concentrations of cadmium, copper, iron, and zinc correlated in liver and muscle, suggesting that uptake and pathways of metabolism and storage were similar for these elements. The major POPs were 4,4′-DDE, mirex, PCB-153 and PCB-138. The concentrations and tissue distribution patterns of environmental contaminants were overall in accordance with previous results in other seabirds. Conversely, some Antarctic prions showed surprisingly high concentrations of BDE-209. This compound has been rarely observed in seabirds before, and its presence in Antarctic prions could be due to the species feeding habits or to the ingestion of plastic debris. Overall, the study shows that relatively lower trophic level seabirds (zooplankton-eaters) breeding in the remote southern Indian Ocean are exposed to a wide range of environmental contaminants, in particular cadmium, selenium and some emerging-POPs, which merits further toxicological investigations. - Highlights: • Trace elements and POPs were measured in various tissues of 10 Antarctic prions. • Residue diversity was notable given the species' small size and low trophic position. • Cd, Se, BDE 183 and 209 showed noticeably high internal tissue concentrations. • Several POPs showed inter- and intra-tissue correlations, indicating co-exposure. • Blood was validated as a good bioindicator of internal tissue As and Hg levels.

Wide range of metallic and organic contaminants in various tissues of the Antarctic prion, a planktonophagous seabird from the Southern Ocean

Energy Technology Data Exchange (ETDEWEB)

Fromant, Aymeric [Centre d' Etudes Biologiques de Chizé, UMR 7372 CNRS—Université de La Rochelle, 79360 Villiers-en-Bois (France); Carravieri, Alice, E-mail: carravieri@cebc.cnrs.fr [Centre d' Etudes Biologiques de Chizé, UMR 7372 CNRS—Université de La Rochelle, 79360 Villiers-en-Bois (France); Littoral Environnement et Sociétés (LIENSs), UMR 7266 CNRS—Université de la Rochelle, 2 rue Olympe de Gouges, 17000 La Rochelle (France); Bustamante, Paco [Littoral Environnement et Sociétés (LIENSs), UMR 7266 CNRS—Université de la Rochelle, 2 rue Olympe de Gouges, 17000 La Rochelle (France); Labadie, Pierre; Budzinski, Hélène; Peluhet, Laurent [Université de Bordeaux, UMR 5805 EPOC (LPTC Research Group), Université Bordeaux, 351 Cours de la Libération, F 33405 Talence Cedex (France); Churlaud, Carine [Littoral Environnement et Sociétés (LIENSs), UMR 7266 CNRS—Université de la Rochelle, 2 rue Olympe de Gouges, 17000 La Rochelle (France); Chastel, Olivier; Cherel, Yves [Centre d' Etudes Biologiques de Chizé, UMR 7372 CNRS—Université de La Rochelle, 79360 Villiers-en-Bois (France)

2016-02-15

ABSTRACT: Trace elements (n = 14) and persistent organic pollutants (POPs, n = 30) were measured in blood, liver, kidney, muscle and feathers of 10 Antarctic prions (Pachyptila desolata) from Kerguelen Islands, southern Indian Ocean, in order to assess their concentrations, tissue distribution, and inter-tissue and inter-contaminant relationships. Liver, kidney and feathers presented the highest burdens of arsenic, cadmium and mercury, respectively. Concentrations of cadmium, copper, iron, and zinc correlated in liver and muscle, suggesting that uptake and pathways of metabolism and storage were similar for these elements. The major POPs were 4,4′-DDE, mirex, PCB-153 and PCB-138. The concentrations and tissue distribution patterns of environmental contaminants were overall in accordance with previous results in other seabirds. Conversely, some Antarctic prions showed surprisingly high concentrations of BDE-209. This compound has been rarely observed in seabirds before, and its presence in Antarctic prions could be due to the species feeding habits or to the ingestion of plastic debris. Overall, the study shows that relatively lower trophic level seabirds (zooplankton-eaters) breeding in the remote southern Indian Ocean are exposed to a wide range of environmental contaminants, in particular cadmium, selenium and some emerging-POPs, which merits further toxicological investigations. - Highlights: • Trace elements and POPs were measured in various tissues of 10 Antarctic prions. • Residue diversity was notable given the species' small size and low trophic position. • Cd, Se, BDE 183 and 209 showed noticeably high internal tissue concentrations. • Several POPs showed inter- and intra-tissue correlations, indicating co-exposure. • Blood was validated as a good bioindicator of internal tissue As and Hg levels.

Engineering complex orthopaedic tissues via strategic biomimicry.

Science.gov (United States)

Qu, Dovina; Mosher, Christopher Z; Boushell, Margaret K; Lu, Helen H

2015-03-01

The primary current challenge in regenerative engineering resides in the simultaneous formation of more than one type of tissue, as well as their functional assembly into complex tissues or organ systems. Tissue-tissue synchrony is especially important in the musculoskeletal system, wherein overall organ function is enabled by the seamless integration of bone with soft tissues such as ligament, tendon, or cartilage, as well as the integration of muscle with tendon. Therefore, in lieu of a traditional single-tissue system (e.g., bone, ligament), composite tissue scaffold designs for the regeneration of functional connective tissue units (e.g., bone-ligament-bone) are being actively investigated. Closely related is the effort to re-establish tissue-tissue interfaces, which is essential for joining these tissue building blocks and facilitating host integration. Much of the research at the forefront of the field has centered on bioinspired stratified or gradient scaffold designs which aim to recapitulate the structural and compositional inhomogeneity inherent across distinct tissue regions. As such, given the complexity of these musculoskeletal tissue units, the key question is how to identify the most relevant parameters for recapitulating the native structure-function relationships in the scaffold design. Therefore, the focus of this review, in addition to presenting the state-of-the-art in complex scaffold design, is to explore how strategic biomimicry can be applied in engineering tissue connectivity. The objective of strategic biomimicry is to avoid over-engineering by establishing what needs to be learned from nature and defining the essential matrix characteristics that must be reproduced in scaffold design. Application of this engineering strategy for the regeneration of the most common musculoskeletal tissue units (e.g., bone-ligament-bone, muscle-tendon-bone, cartilage-bone) will be discussed in this review. It is anticipated that these exciting efforts will

Engineering Complex Orthopaedic Tissues via Strategic Biomimicry

Science.gov (United States)

Qu, Dovina; Mosher, Christopher Z.; Boushell, Margaret K.; Lu, Helen H.

2014-01-01

The primary current challenge in regenerative engineering resides in the simultaneous formation of more than one type of tissue, as well as their functional assembly into complex tissues or organ systems. Tissue-tissue synchrony is especially important in the musculoskeletal system, whereby overall organ function is enabled by the seamless integration of bone with soft tissues such as ligament, tendon, or cartilage, as well as the integration of muscle with tendon. Therefore, in lieu of a traditional single-tissue system (e.g. bone, ligament), composite tissue scaffold designs for the regeneration of functional connective tissue units (e.g. bone-ligament-bone) are being actively investigated. Closely related is the effort to re-establish tissue-tissue interfaces, which is essential for joining these tissue building blocks and facilitating host integration. Much of the research at the forefront of the field has centered on bioinspired stratified or gradient scaffold designs which aim to recapitulate the structural and compositional inhomogeneity inherent across distinct tissue regions. As such, given the complexity of these musculoskeletal tissue units, the key question is how to identify the most relevant parameters for recapitulating the native structure-function relationships in the scaffold design. Therefore, the focus of this review, in addition to presenting the state-of-the-art in complex scaffold design, is to explore how strategic biomimicry can be applied in engineering tissue connectivity. The objective of strategic biomimicry is to avoid over-engineering by establishing what needs to be learned from nature and defining the essential matrix characteristics that must be reproduced in scaffold design. Application of this engineering strategy for the regeneration of the most common musculoskeletal tissue units (e.g. bone-ligament-bone, muscle-tendon-bone, cartilage-bone) will be discussed in this review. It is anticipated that these exciting efforts will

Dynamic impact indentation of hydrated biological tissues and tissue surrogate gels

Science.gov (United States)

Ilke Kalcioglu, Z.; Qu, Meng; Strawhecker, Kenneth E.; Shazly, Tarek; Edelman, Elazer; VanLandingham, Mark R.; Smith, James F.; Van Vliet, Krystyn J.

2011-03-01

For both materials engineering research and applied biomedicine, a growing need exists to quantify mechanical behaviour of tissues under defined hydration and loading conditions. In particular, characterisation under dynamic contact-loading conditions can enable quantitative predictions of deformation due to high rate 'impact' events typical of industrial accidents and ballistic insults. The impact indentation responses were examined of both hydrated tissues and candidate tissue surrogate materials. The goals of this work were to determine the mechanical response of fully hydrated soft tissues under defined dynamic loading conditions, and to identify design principles by which synthetic, air-stable polymers could mimic those responses. Soft tissues from two organs (liver and heart), a commercially available tissue surrogate gel (Perma-Gel™) and three styrenic block copolymer gels were investigated. Impact indentation enabled quantification of resistance to penetration and energy dissipative constants under the rates and energy densities of interest for tissue surrogate applications. These analyses indicated that the energy dissipation capacity under dynamic impact increased with increasing diblock concentration in the styrenic gels. Under the impact rates employed (2 mm/s to 20 mm/s, corresponding to approximate strain energy densities from 0.4 kJ/m3 to 20 kJ/m3), the energy dissipation capacities of fully hydrated soft tissues were ultimately well matched by a 50/50 triblock/diblock composition that is stable in ambient environments. More generally, the methodologies detailed here facilitate further optimisation of impact energy dissipation capacity of polymer-based tissue surrogate materials, either in air or in fluids.

Using endografts from superelastic titanium-nickelid-based alloy singular tissue plural tissues in organ-preserving surgery of laryngeal cancer

Energy Technology Data Exchange (ETDEWEB)

Kulbakin, D. E., E-mail: kulbakin-d@mail.ru [Tomsk Cancer Research Institute, 5 Kooperativny Street, Tomsk, 634050 (Russian Federation); Tomsk State University, 36, Lenin Avenue, Tomsk, 634050 (Russian Federation); Mukhamedov, M. R., E-mail: muhamedov@oncology.tomsk.ru [Tomsk Cancer Research Institute, 5 Kooperativny Street, Tomsk, 634050 (Russian Federation); Siberian State Medical University, 2, Moscow Highway, Tomsk, 634050 (Russian Federation); Choynzonov, E. L., E-mail: choynzonov@gmail.com [Tomsk Cancer Research Institute, 5 Kooperativny Street, Tomsk, 634050 (Russian Federation); Siberian State Medical University, 2, Moscow Highway, Tomsk, 634050 (Russian Federation); National Research Tomsk Polytechnic University, 30, Lenin Avenue, Tomsk, 634050 (Russian Federation); Gynter, V. E., E-mail: tc77@rec.tsu.ru [Tomsk State University, 36, Lenin Avenue, Tomsk, 634050 (Russian Federation); Research Institute of Medical Materials, 17, 19 Gv. Divizii, Tomsk, 634034 (Russian Federation)

2015-11-17

Our study has demonstrated feasibility of performing larynx preservation surgeries in patients with recurrent laryngeal cancer after failure of radiotherapy. The technique of combined laryngeal reconstruction with endografts from superelastic titanium-nickelid-based alloy Singular tissue Plural tissues results in improvement of life quality by preserving laryngeal functions.

The use of animal tissues alongside human tissue: Cultural and ethical considerations.

Science.gov (United States)

Kaw, Anu; Jones, D Gareth; Zhang, Ming

2016-01-01

Teaching and research facilities often use cadaveric material alongside animal tissues, although there appear to be differences in the way we handle, treat, and dispose of human cadaveric material compared to animal tissue. This study sought to analyze cultural and ethical considerations and provides policy recommendations on the use of animal tissues alongside human tissue. The status of human and animal remains and the respect because of human and animal tissues were compared and analyzed from ethical, legal, and cultural perspectives. The use of animal organs and tissues is carried out within the context of understanding human anatomy and function. Consequently, the interests of human donors are to be pre-eminent in any policies that are enunciated, so that if any donors find the presence of animal remains unacceptable, the latter should not be employed. The major differences appear to lie in differences in our perceptions of their respective intrinsic and instrumental values. Animals are considered to have lesser intrinsic value and greater instrumental value than humans. These differences stem from the role played by culture and ethical considerations, and are manifested in the resulting legal frameworks. In light of this discussion, six policy recommendations are proposed, encompassing the nature of consent, respect for animal tissues as well as human remains, and appropriate separation of both sets of tissues in preparation and display. © 2015 Wiley Periodicals, Inc.

Characterization of cDNA encoding molt-inhibiting hormone of the crab, Cancer pagurus; expression of MIH in non-X-organ tissues.

Science.gov (United States)

Lu, W; Wainwright, G; Olohan, L A; Webster, S G; Rees, H H; Turner, P C

2001-10-31

Synthesis of ecdysteroids (molting hormones) by crustacean Y-organs is regulated by a neuropeptide, molt-inhibiting hormone (MIH), produced in eyestalk neural ganglia. We report here the molecular cloning of a cDNA encoding MIH of the edible crab, Cancer pagurus. Full-length MIH cDNA was obtained by using reverse transcription-polymerase chain reaction (RT-PCR) with degenerate oligonucleotides based upon the amino acid sequence of MIH, in conjunction with 5'- and 3'-RACE. Full-length clones of MIH cDNA were obtained that encoded a 35 amino acid putative signal peptide and the mature 78 amino acid peptide. Of various tissues examined by Northern blot analysis, the X-organ was the sole major site of expression of the MIH gene. However, a nested-PCR approach using non-degenerate MIH-specific primers indicated the presence of MIH transcripts in other tissues. Southern blot analysis indicated a simple gene arrangement with at least two copies of the MIH gene in the genome of C. pagurus. Additional Southern blotting experiments detected MIH-hybridizing bands in another Cancer species, Cancer antennarius and another crab species, Carcinus maenas.

Tissue-based map of the human proteome

DEFF Research Database (Denmark)

Uhlén, Mathias; Fagerberg, Linn; Hallström, Björn M.

2015-01-01

Resolving the molecular details of proteome variation in the different tissues and organs of the human body will greatly increase our knowledge of human biology and disease. Here, we present a map of the human tissue proteome based on an integrated omics approach that involves quantitative transc...

Shaping tissues by balancing active forces and geometric constraints

Science.gov (United States)

Foolen, Jasper; Yamashita, Tadahiro; Kollmannsberger, Philip

2016-02-01

The self-organization of cells into complex tissues during growth and regeneration is a combination of physical-mechanical events and biochemical signal processing. Cells actively generate forces at all stages in this process, and according to the laws of mechanics, these forces result in stress fields defined by the geometric boundary conditions of the cell and tissue. The unique ability of cells to translate such force patterns into biochemical information and vice versa sets biological tissues apart from any other material. In this topical review, we summarize the current knowledge and open questions of how forces and geometry act together on scales from the single cell to tissues and organisms, and how their interaction determines biological shape and structure. Starting with a planar surface as the simplest type of geometric constraint, we review literature on how forces during cell spreading and adhesion together with geometric constraints impact cell shape, stress patterns, and the resulting biological response. We then move on to include cell-cell interactions and the role of forces in monolayers and in collective cell migration, and introduce curvature at the transition from flat cell sheets to three-dimensional (3D) tissues. Fibrous 3D environments, as cells experience them in the body, introduce new mechanical boundary conditions and change cell behaviour compared to flat surfaces. Starting from early work on force transmission and collagen remodelling, we discuss recent discoveries on the interaction with geometric constraints and the resulting structure formation and network organization in 3D. Recent literature on two physiological scenarios—embryonic development and bone—is reviewed to demonstrate the role of the force-geometry balance in living organisms. Furthermore, the role of mechanics in pathological scenarios such as cancer is discussed. We conclude by highlighting common physical principles guiding cell mechanics, tissue patterning and

Shaping tissues by balancing active forces and geometric constraints

International Nuclear Information System (INIS)

Foolen, Jasper; Yamashita, Tadahiro; Kollmannsberger, Philip

2016-01-01

The self-organization of cells into complex tissues during growth and regeneration is a combination of physical–mechanical events and biochemical signal processing. Cells actively generate forces at all stages in this process, and according to the laws of mechanics, these forces result in stress fields defined by the geometric boundary conditions of the cell and tissue. The unique ability of cells to translate such force patterns into biochemical information and vice versa sets biological tissues apart from any other material. In this topical review, we summarize the current knowledge and open questions of how forces and geometry act together on scales from the single cell to tissues and organisms, and how their interaction determines biological shape and structure. Starting with a planar surface as the simplest type of geometric constraint, we review literature on how forces during cell spreading and adhesion together with geometric constraints impact cell shape, stress patterns, and the resulting biological response. We then move on to include cell–cell interactions and the role of forces in monolayers and in collective cell migration, and introduce curvature at the transition from flat cell sheets to three-dimensional (3D) tissues. Fibrous 3D environments, as cells experience them in the body, introduce new mechanical boundary conditions and change cell behaviour compared to flat surfaces. Starting from early work on force transmission and collagen remodelling, we discuss recent discoveries on the interaction with geometric constraints and the resulting structure formation and network organization in 3D. Recent literature on two physiological scenarios—embryonic development and bone—is reviewed to demonstrate the role of the force-geometry balance in living organisms. Furthermore, the role of mechanics in pathological scenarios such as cancer is discussed. We conclude by highlighting common physical principles guiding cell mechanics, tissue patterning

Combined Bisulfite Restriction Analysis for brain tissue identification.

Science.gov (United States)

Samsuwan, Jarunya; Muangsub, Tachapol; Yanatatsaneejit, Pattamawadee; Mutirangura, Apiwat; Kitkumthorn, Nakarin

2018-05-01

According to the tissue-specific methylation database (doi: 10.1016/j.gene.2014.09.060), methylation at CpG locus cg03096975 in EML2 has been preliminarily proven to be specific to brain tissue. In this study, we enlarged sample size and developed a technique for identifying brain tissue in aged samples. Combined Bisulfite Restriction Analysis-for EML2 (COBRA-EML2) technique was established and validated in various organ samples obtained from 108 autopsies. In addition, this technique was also tested for its reliability, minimal DNA concentration detected, and use in aged samples and in samples obtained from specific brain compartments and spinal cord. COBRA-EML2 displayed 100% sensitivity and specificity for distinguishing brain tissue from other tissues, showed high reliability, was capable of detecting minimal DNA concentration (0.015ng/μl), could be used for identifying brain tissue in aged samples. In summary, COBRA-EML2 is a technique to identify brain tissue. This analysis is useful in criminal cases since it can identify the vital organ tissues from small samples acquired from criminal scenes. The results from this analysis can be counted as a medical and forensic marker supporting criminal investigations, and as one of the evidences in court rulings. Copyright © 2018 Elsevier B.V. All rights reserved.

Bioengineering of Artificial Lymphoid Organs.

Science.gov (United States)

Nosenko, M A; Drutskaya, M S; Moisenovich, M M; Nedospasov, S A

2016-01-01

This review addresses the issue of bioengineering of artificial lymphoid organs.Progress in this field may help to better understand the nature of the structure-function relations that exist in immune organs. Artifical lymphoid organs may also be advantageous in the therapy or correction of immunodefficiencies, autoimmune diseases, and cancer. The structural organization, development, and function of lymphoid tissue are analyzed with a focus on the role of intercellular contacts and on the cytokine signaling pathways regulating these processes. We describe various polymeric materials, as scaffolds, for artificial tissue engineering. Finally, published studies in which artificial lymphoid organs were generated are reviewed and possible future directions in the field are discussed.

Temperature dependence of postmortem MR quantification for soft tissue discrimination

Energy Technology Data Exchange (ETDEWEB)

Zech, Wolf-Dieter; Schwendener, Nicole; Jackowski, Christian [University of Bern, From the Institute of Forensic Medicine, Bern (Switzerland); Persson, Anders; Warntjes, Marcel J. [University of Linkoeping, The Center for Medical Image Science and Visualization (CMIV), Linkoeping (Sweden)

2015-08-15

To investigate and correct the temperature dependence of postmortem MR quantification used for soft tissue characterization and differentiation in thoraco-abdominal organs. Thirty-five postmortem short axis cardiac 3-T MR examinations were quantified using a quantification sequence. Liver, spleen, left ventricular myocardium, pectoralis muscle and subcutaneous fat were analysed in cardiac short axis images to obtain mean T1, T2 and PD tissue values. The core body temperature was measured using a rectally inserted thermometer. The tissue-specific quantitative values were related to the body core temperature. Equations to correct for temperature differences were generated. In a 3D plot comprising the combined data of T1, T2 and PD, different organs/tissues could be well differentiated from each other. The quantitative values were influenced by the temperature. T1 in particular exhibited strong temperature dependence. The correction of quantitative values to a temperature of 37 C resulted in better tissue discrimination. Postmortem MR quantification is feasible for soft tissue discrimination and characterization of thoraco-abdominal organs. This provides a base for computer-aided diagnosis and detection of tissue lesions. The temperature dependence of the T1 values challenges postmortem MR quantification. Equations to correct for the temperature dependence are provided. (orig.)

Temperature dependence of postmortem MR quantification for soft tissue discrimination

International Nuclear Information System (INIS)

Zech, Wolf-Dieter; Schwendener, Nicole; Jackowski, Christian; Persson, Anders; Warntjes, Marcel J.

2015-01-01

To investigate and correct the temperature dependence of postmortem MR quantification used for soft tissue characterization and differentiation in thoraco-abdominal organs. Thirty-five postmortem short axis cardiac 3-T MR examinations were quantified using a quantification sequence. Liver, spleen, left ventricular myocardium, pectoralis muscle and subcutaneous fat were analysed in cardiac short axis images to obtain mean T1, T2 and PD tissue values. The core body temperature was measured using a rectally inserted thermometer. The tissue-specific quantitative values were related to the body core temperature. Equations to correct for temperature differences were generated. In a 3D plot comprising the combined data of T1, T2 and PD, different organs/tissues could be well differentiated from each other. The quantitative values were influenced by the temperature. T1 in particular exhibited strong temperature dependence. The correction of quantitative values to a temperature of 37 C resulted in better tissue discrimination. Postmortem MR quantification is feasible for soft tissue discrimination and characterization of thoraco-abdominal organs. This provides a base for computer-aided diagnosis and detection of tissue lesions. The temperature dependence of the T1 values challenges postmortem MR quantification. Equations to correct for the temperature dependence are provided. (orig.)

An overview of the analytical methods for the determination of organic ultraviolet filters in biological fluids and tissues

Energy Technology Data Exchange (ETDEWEB)

Chisvert, Alberto, E-mail: alberto.chisvert@uv.es [Departamento de Quimica Analitica, Facultad de Quimica, Universitat de Valencia, Doctor Moliner St. 50, 46100 Burjassot, Valencia (Spain); Leon-Gonzalez, Zacarias [Unidad Analitica, Instituto de Investigacion Sanitaria Fundacion Hospital La Fe, 46009 Valencia (Spain); Tarazona, Isuha; Salvador, Amparo [Departamento de Quimica Analitica, Facultad de Quimica, Universitat de Valencia, Doctor Moliner St. 50, 46100 Burjassot, Valencia (Spain); Giokas, Dimosthenis [Laboratory of Analytical Chemistry, Department of Chemistry, University of Ioannina, 45110 Ioannina (Greece)

2012-11-08

Highlights: Black-Right-Pointing-Pointer Papers describing the determination of UV filters in fluids and tissues are reviewed. Black-Right-Pointing-Pointer Matrix complexity and low amounts of analytes require effective sample treatments. Black-Right-Pointing-Pointer The published papers do not cover the study of all the substances allowed as UV filters. Black-Right-Pointing-Pointer New analytical methods for UV filters determination in these matrices are encouraged. - Abstract: Organic UV filters are chemical compounds added to cosmetic sunscreen products in order to protect users from UV solar radiation. The need of broad-spectrum protection to avoid the deleterious effects of solar radiation has triggered a trend in the cosmetic market of including these compounds not only in those exclusively designed for sun protection but also in all types of cosmetic products. Different studies have shown that organic UV filters can be absorbed through the skin after topical application, further metabolized in the body and eventually excreted or bioaccumulated. These percutaneous absorption processes may result in various adverse health effects, such as genotoxicity caused by the generation of free radicals, which can even lead to mutagenic or carcinogenic effects, and estrogenicity, which is associated with the endocrine disruption activity caused by some of these compounds. Due to the absence of official monitoring protocols, there is a demand for analytical methods that enable the determination of UV filters in biological fluids and tissues in order to retrieve more information regarding their behavior in the human body and thus encourage the development of safer cosmetic formulations. In view of this demand, there has recently been a noticeable increase in the development of sensitive and selective analytical methods for the determination of UV filters and their metabolites in biological fluids (i.e., urine, plasma, breast milk and semen) and tissues. The complexity of

An overview of the analytical methods for the determination of organic ultraviolet filters in biological fluids and tissues

International Nuclear Information System (INIS)

Chisvert, Alberto; León-González, Zacarías; Tarazona, Isuha; Salvador, Amparo; Giokas, Dimosthenis

2012-01-01

Highlights: ► Papers describing the determination of UV filters in fluids and tissues are reviewed. ► Matrix complexity and low amounts of analytes require effective sample treatments. ► The published papers do not cover the study of all the substances allowed as UV filters. ► New analytical methods for UV filters determination in these matrices are encouraged. - Abstract: Organic UV filters are chemical compounds added to cosmetic sunscreen products in order to protect users from UV solar radiation. The need of broad-spectrum protection to avoid the deleterious effects of solar radiation has triggered a trend in the cosmetic market of including these compounds not only in those exclusively designed for sun protection but also in all types of cosmetic products. Different studies have shown that organic UV filters can be absorbed through the skin after topical application, further metabolized in the body and eventually excreted or bioaccumulated. These percutaneous absorption processes may result in various adverse health effects, such as genotoxicity caused by the generation of free radicals, which can even lead to mutagenic or carcinogenic effects, and estrogenicity, which is associated with the endocrine disruption activity caused by some of these compounds. Due to the absence of official monitoring protocols, there is a demand for analytical methods that enable the determination of UV filters in biological fluids and tissues in order to retrieve more information regarding their behavior in the human body and thus encourage the development of safer cosmetic formulations. In view of this demand, there has recently been a noticeable increase in the development of sensitive and selective analytical methods for the determination of UV filters and their metabolites in biological fluids (i.e., urine, plasma, breast milk and semen) and tissues. The complexity of the biological matrix and the low concentration levels of these compounds inevitably impose sample

Pulsed Ultraviolet Light Reduces Immunoglobulin E Binding to Atlantic White Shrimp (Litopenaeus setiferus Extract

Directory of Open Access Journals (Sweden)

Si-Yin Chung

2011-06-01

Full Text Available Pulsed ultraviolet light (PUV, a novel food processing and preservation technology, has been shown to reduce allergen levels in peanut and soybean samples. In this study, the efficacy of using PUV to reduce the reactivity of the major shrimp allergen, tropomyosin (36-kDa, and to attenuate immunoglobulin E (IgE binding to shrimp extract was examined. Atlantic white shrimp (Litopenaeus setiferus extract was treated with PUV (3 pulses/s, 10 cm from light source for 4 min. Tropomyosin was compared in the untreated, boiled, PUV-treated and [boiled+PUV]-treated samples, and changes in the tropomyosin levels were determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE. IgE binding of the treated extract was analyzed via immunoblot and enzyme-linked immunosorbent assay (ELISA using pooled human plasma containing IgE antibodies against shrimp allergens. Results showed that levels of tropomyosin and IgE binding were reduced following PUV treatment. However, boiling increased IgE binding, while PUV treatment could offset the increased allergen reactivity caused by boiling. In conclusion, PUV treatment reduced the reactivity of the major shrimp allergen, tropomyosin, and decreased the IgE binding capacity of the shrimp extract.

Intra-population variability of ocean acidification impacts on the physiology of Baltic blue mussels (Mytilus edulis): integrating tissue and organism response.

Science.gov (United States)

Stapp, L S; Thomsen, J; Schade, H; Bock, C; Melzner, F; Pörtner, H O; Lannig, G

2017-05-01

Increased maintenance costs at cellular, and consequently organism level, are thought to be involved in shaping the sensitivity of marine calcifiers to ocean acidification (OA). Yet, knowledge of the capacity of marine calcifiers to undergo metabolic adaptation is sparse. In Kiel Fjord, blue mussels thrive despite periodically high seawater PCO 2 , making this population interesting for studying metabolic adaptation under OA. Consequently, we conducted a multi-generation experiment and compared physiological responses of F1 mussels from 'tolerant' and 'sensitive' families exposed to OA for 1 year. Family classifications were based on larval survival; tolerant families settled at all PCO 2 levels (700, 1120, 2400 µatm) while sensitive families did not settle at the highest PCO 2 (≥99.8% mortality). We found similar filtration rates between family types at the control and intermediate PCO 2 level. However, at 2400 µatm, filtration and metabolic scope of gill tissue decreased in tolerant families, indicating functional limitations at the tissue level. Routine metabolic rates (RMR) and summed tissue respiration (gill and outer mantle tissue) of tolerant families were increased at intermediate PCO 2 , indicating elevated cellular homeostatic costs in various tissues. By contrast, OA did not affect tissue and routine metabolism of sensitive families. However, tolerant mussels were characterised by lower RMR at control PCO 2 than sensitive families, which had variable RMR. This might provide the energetic scope to cover increased energetic demands under OA, highlighting the importance of analysing intra-population variability. The mechanisms shaping such difference in RMR and scope, and thus species' adaptation potential, remain to be identified.

Real-time Visualization of Tissue Dynamics during Embryonic Development and Malignant Transformation

Science.gov (United States)

Yamada, Kenneth

Tissues undergo dramatic changes in organization during embryonic development, as well as during cancer progression and invasion. Recent advances in microscopy now allow us to visualize and track directly the dynamic movements of tissues, their constituent cells, and cellular substructures. This behavior can now be visualized not only in regular tissue culture on flat surfaces (`2D' environments), but also in a variety of 3D environments that may provide physiological cues relevant to understanding dynamics within living organisms. Acquisition of imaging data using various microscopy modalities will provide rich opportunities for determining the roles of physical factors and for computational modeling of complex processes in living tissues. Direct visualization of real-time motility is providing insight into biology spanning multiple spatio-temporal scales. Many cells in our body are known to be in contact with connective tissue and other forms of extracellular matrix. They do so through microscopic cellular adhesions that bind to matrix proteins. In particular, fluorescence microscopy has revealed that cells dynamically probe and bend the matrix at the sites of cell adhesions, and that 3D matrix architecture, stiffness, and elasticity can each regulate migration of the cells. Conversely, cells remodel their local matrix as organs form or tumors invade. Cancer cells can invade tissues using microscopic protrusions that degrade the surrounding matrix; in this case, the local matrix protein concentration is more important for inducing the micro-invasive protrusions than stiffness. On the length scales of tissues, transiently high rates of individual cell movement appear to help establish organ architecture. In fact, isolated cells can self-organize to form tissue structures. In all of these cases, in-depth real-time visualization will ultimately provide the extensive data needed for computer modeling and for testing hypotheses in which physical forces interact

Team-building through sailing: effects on health status, job satisfaction and work performance of health care professionals involved in organ and tissue donation.

Science.gov (United States)

Ponzin, Diego; Fasolo, Adriano; Vidale, Enrico; Pozzi, Annalaura; Bottignolo, Elisa; Calabrò, Francesco; Rupolo, Giampietro

2015-01-01

The aim of this study was to evaluate the effects of a team-building learning project on job satisfaction, psychological wellbeing, and performance of health care workers involved in the process of organ and tissue donation. The project was conducted between June and September 2011 and consisted of two one-day meetings and a one week sailing, involving 20 staff members. GHQ-12, MBI-HSS, and 25 items taken from the Multidimensional Organizational Health Questionnaire (MOHQ) were used to assess health status, burnout, and job satisfaction. Results of the descriptive analyses were expressed as mean ± SD and as counts and percentages; Chi-square test was used to evaluate statistical significance of differences before and after the initiative. 6 (30,0%) participants showed the likelihood to suffering from anxiety and depression (i.e. recognized as 'cases' by the GHQ-12), 3 (15.0%) of them at baseline and 3 (15.0%), different from the previous ones, in the post-intervention. The presence of stress was revealed in 9 (45.0%) and 12 subjects (60.0%) before and after the experience, respectively (6 subjects showed the presence of stress in both circumstances). We documented 4 burnout cases, 3 (15.0%) at baseline and 1 (5.0%) after the experience. Nevertheless, about 80% of the participants showed a high degree ofjob satisfaction, in terms of positive influence of job in the professional satisfaction and of clear satisfaction for the organization, during both evaluation. In respect to 2010, the number of organ donors and that of ocular tissue donors improved of about 16% and 10%, respectively, during the year of the project and in the following year (mean value). We recognize that our team-building project for personnel involved in the stressful and demanding setting of organ and tissue donation, worthwhile and recompensing at the same time, possibly influenced the personal commitment and the quality of job provided. The high level of stress showed by participants should be

The Nanomechanics of Biomineralized Soft-Tissues and Organic Matrices

Science.gov (United States)

Bezares-Chavez, Jiddu

The research reported on in this dissertation is concerned with the macro-molecular constitution and geometrical organization of the soft-tissue comprising the matrix of the nacreous portion of the shell of Haliotis rufescens, the Red abalone. Nacre is one of literally legions of intricate biomineralized structures that exist in nature and has long served as a paradigm for elegant and optimized structural de-sign. Biomineralization involves, inter alia, the uptake and synthesis of elements and compounds from the environment and their incorporation into highly optimized functional structures. Nacre has a structure described as a brick wall like with a matrix of biopolymer layers that are preformed and serve as a template into which nanocrystalline tiles of CaCO3 precipitate. The matrix, or what are known as inter-lamellar layers, are of particular interest as they impart both toughness and strength to the composite ceramic nacre structure. The work first involved a histochemical mapping of the macromolecular structure of the interlamellar layers; this revealed the locations of proteins and functional molecular groups that serve as nucleation sites for the ceramic tiles. Parallel studies on the nacre of Nautilus pompilius, the Chambered Nautilus, revealed the generality of the findings. Of particular interest was determining both the content and layout of chitin within these layers. In fact it was determined that chitin was organized as mostly unidirectional architecture of fibrils, with a certain fraction of fibrils laying at cross directions. Most remarkably, it was found that the fibrils possessed a very long range connectivity that spanned many tiles. This was determined by systematic atomic force (afm) and analytical optical histochemical microscopy. These findings were further verified by a unique form of mechanical testing whereby tensile testing was conducted on groups of interlamellar layers extracted from nacre. Mechanical testing led to a quantitative

Status quo of management of the human tissue banks in Taiwan.

Science.gov (United States)

Chou, Ching-Pang; Chou, Szu-Cheng; Chen, Ying-Hua; Chen, Yu-Hsuan; Lee, Ming-Shin

2017-03-01

As the technologies associated with transplantation and biological tissue engineering continue to advance, human cells and tissues form an integral part to the practice of regenerative medicine. The patient's use of tissues entails the risk of introducing, transmitting and spreading communicable diseases. To prevent such risk and to ensure that the human organs, tissues and cells remain intact and functional after being handled and processed, the transplanted tissues must be subject to good management standards through all stages of collection, screening, processing, storage and distribution as the safety of the users is of the utmost importance. On February 2009, the government of Taiwan promulgated the Regulations for Administration on Human Organ Bank that requires all human tissues banks to adhere to the Good Tissue Practice for Human Organ, Tissue and Cell in terms of establishment and operation in order to cope with the international management trend and the development and management need of the domestic industry. Six years have passed since the law became effective. This article seeks to introduce the current management mechanism and status quo of management of human tissue banks in Taiwan. We also conducted statistical analysis of the data relating to the tissue banks to identify potential risks and the room for improvement. The study concludes that human tissue banks in Taiwan are on the right track with their management practice, leading to a state of steady development and progress.

3D Bioprinting for Organ Regeneration

Science.gov (United States)

Cui, Haitao; Nowicki, Margaret; Fisher, John P.; Zhang, Lijie Grace

2017-01-01

Regenerative medicine holds the promise of engineering functional tissues or organs to heal or replace abnormal and necrotic tissues/organs, offering hope for filling the gap between organ shortage and transplantation needs. Three-dimensional (3D) bioprinting is evolving into an unparalleled bio-manufacturing technology due to its high-integration potential for patient-specific designs, precise and rapid manufacturing capabilities with high resolution, and unprecedented versatility. It enables precise control over multiple compositions, spatial distributions, and architectural accuracy/complexity, therefore achieving effective recapitulation of microstructure, architecture, mechanical properties, and biological functions of target tissues and organs. Here we provide an overview of recent advances in 3D bioprinting technology, as well as design concepts of bioinks suitable for the bioprinting process. We focus on the applications of this technology for engineering living organs, focusing more specifically on vasculature, neural networks, the heart and liver. We conclude with current challenges and the technical perspective for further development of 3D organ bioprinting. PMID:27995751

Can δ(15)N in lettuce tissues reveal the use of synthetic nitrogen fertiliser in organic production?

Science.gov (United States)

Sturm, Martina; Kacjan-Maršić, Nina; Lojen, Sonja

2011-01-30

The nitrogen isotopic fingerprint (δ(15)N) is reported to be a promising indicator for differentiating between organically and conventionally grown vegetables. However, the effect on plant δ(15)N of split nitrogen fertilisation, which could enable farmers to cover up the use of synthetic fertiliser, is not well studied. In this study the use of δ(15)N in lettuce as a potential marker for identifying the use of synthetic nitrogen fertiliser was tested on pot-grown lettuce (Lactuca sativa L.) treated with synthetic and organic nitrogen fertilisers (single or split application). The effect of combined usage of synthetic and organic fertilisers on δ(15)N was also investigated. The δ(15)N values of whole plants treated with different fertilisers differed significantly when the fertiliser was applied in a single treatment. However, additional fertilisation (with isotopically the same or different fertiliser) did not cause a significant alteration of plant δ(15)N. The findings of the study suggest that the δ(15)N value of lettuce tissues could be used as a rough marker to reveal the history of nitrogen fertilisation, but only in the case of single fertiliser application. However, if the difference in δ(15)N between the applied synthetic and organic nitrogen fertilisers was > 9.1 ‰, the detection of split and combined usage of the fertilisers would have greater discriminatory power. 2010 Society of Chemical Industry.

Nonmuscle Tissues Contribution to Cancer Cachexia

Directory of Open Access Journals (Sweden)

Josep M. Argilés

2015-01-01

Full Text Available Cachexia is a syndrome associated with cancer, characterized by body weight loss, muscle and adipose tissue wasting, and inflammation, being often associated with anorexia. In spite of the fact that muscle tissue represents more than 40% of body weight and seems to be the main tissue involved in the wasting that occurs during cachexia, recent developments suggest that tissues/organs such as adipose (both brown and white, brain, liver, gut, and heart are directly involved in the cachectic process and may be responsible for muscle wasting. This suggests that cachexia is indeed a multiorgan syndrome. Bearing all this in mind, the aim of the present review is to examine the impact of nonmuscle tissues in cancer cachexia.

The profile of potential organ and tissue donors.

Science.gov (United States)

Moraes, Edvaldo Leal de; Silva, Leonardo Borges de Barros E; Moraes, Tatiana Cristine de; Paixão, Nair Cordeiro dos Santos da; Izumi, Nelly Miyuki Shinohara; Guarino, Aparecida de Jesus

2009-01-01

This study aimed to characterize donors according to gender, age group, cause of brain death; quantify donors with hypernatremia, hyperpotassemia and hypopotassemia; and get to know which organs were the most used in transplantations. This quantitative, descriptive, exploratory and retrospective study was performed at the Organ Procurement Organization of the University of São Paulo Medical School Hospital das Clínicas. Data from the medical records of 187 potential donors were analyzed. Cerebrovascular accidents represented 53.48% of all brain death causes, sodium and potassium disorders occurred in 82.36% of cases and 45.46% of the potential donors were between 41 and 60 years old. The results evidenced that natural death causes exceeded traumatic deaths, and that most donors presented sodium and potassium alterations, likely associated to inappropriate maintenance.

Modern Soft Tissue Pathology | Center for Cancer Research

Science.gov (United States)

This book comprehensively covers modern soft tissue pathology and includes both tumors and non-neoplastic entities. Soft tissues make up a large bulk of the human body, and they are susceptible to a wide range of diseases. Many soft-tissue tumors are biologically very aggressive, and the chance of them metastasizing to vital organs is quite high. In recent years, the outlook

GLOBAL CONSULTATION ON ESTABLISHMENT A UNIFIED SURVEILLANCE SYSTEM FOR DONATION AND TRANSPLANTATION OF ORGANS, TISSUES AND CELLS OF HUMAN ORIGIN

Directory of Open Access Journals (Sweden)

O. V. Orlova

2011-01-01

Full Text Available From from February 7th to 9th 2011, the World Health Organization (WHO, the Italian National Transplant Cen- tre and the EU-funded Project «Vigilance and Surveillance of Substances of Human Origin» joined forces to organise a major global consultation that took place in Bologna, Italy. The scope of the project included organs, tissues and cells for transplantation and for assisted reproduction. The participants represented regulatory and non-regulatory government agencies, professional societies and scientific and clinical specialities from all WHO regions. The meeting explored the work already carried out on-line and agreed on priorities for the future deve- lopment of the Project «Vigilance and Surveillance of Substances of Human Origin». 

Esophageal tissue engineering: Current status and perspectives.

Science.gov (United States)

Poghosyan, T; Catry, J; Luong-Nguyen, M; Bruneval, P; Domet, T; Arakelian, L; Sfeir, R; Michaud, L; Vanneaux, V; Gottrand, F; Larghero, J; Cattan, P

2016-02-01

Tissue engineering, which consists of the combination and in vivo implantation of elements required for tissue remodeling toward a specific organ phenotype, could be an alternative for classical techniques of esophageal replacement. The current hybrid approach entails creation of an esophageal substitute composed of an acellular matrix and autologous epithelial and muscle cells provides the most successful results. Current research is based on the use of mesenchymal stem cells, whose potential for differentiation and proangioogenic, immune-modulator and anti-inflammatory properties are important assets. In the near future, esophageal substitutes could be constructed from acellular "intelligent matrices" that contain the molecules necessary for tissue regeneration; this should allow circumvention of the implantation step and still obtain standardized in vivo biological responses. At present, tissue engineering applications to esophageal replacement are limited to enlargement plasties with absorbable, non-cellular matrices. Nevertheless, the application of existing clinical techniques for replacement of other organs by tissue engineering in combination with a multiplication of translational research protocols for esophageal replacement in large animals should soon pave the way for health agencies to authorize clinical trials. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

Development and Characterization of Organic Electronic Scaffolds for Bone Tissue Engineering.

Science.gov (United States)

Iandolo, Donata; Ravichandran, Akhilandeshwari; Liu, Xianjie; Wen, Feng; Chan, Jerry K Y; Berggren, Magnus; Teoh, Swee-Hin; Simon, Daniel T

2016-06-01

Bones have been shown to exhibit piezoelectric properties, generating electrical potential upon mechanical deformation and responding to electrical stimulation with the generation of mechanical stress. Thus, the effects of electrical stimulation on bone tissue engineering have been extensively studied. However, in bone regeneration applications, only few studies have focused on the use of electroactive 3D biodegradable scaffolds at the interphase with stem cells. Here a method is described to combine the bone regeneration capabilities of 3D-printed macroporous medical grade polycaprolactone (PCL) scaffolds with the electrical and electrochemical capabilities of the conducting polymer poly(3,4-ethylenedioxythiophene) (PEDOT). PCL scaffolds have been highly effective in vivo as bone regeneration grafts, and PEDOT is a leading material in the field of organic bioelectronics, due to its stability, conformability, and biocompatibility. A protocol is reported for scaffolds functionalization with PEDOT, using vapor-phase polymerization, resulting in a conformal conducting layer. Scaffolds' porosity and mechanical stability, important for in vivo bone regeneration applications, are retained. Human fetal mesenchymal stem cells proliferation is assessed on the functionalized scaffolds, showing the cytocompatibility of the polymeric coating. Altogether, these results show the feasibility of the proposed approach to obtain electroactive scaffolds for electrical stimulation of stem cells for regenerative medicine. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Human Colors-The Rainbow Garden of Pathology: What Gives Normal and Pathologic Tissues Their Color?

Science.gov (United States)

Piña-Oviedo, Sergio; Ortiz-Hidalgo, Carlos; Ayala, Alberto G

2017-03-01

- Colors are important to all living organisms because they are crucial for camouflage and protection, metabolism, sexual behavior, and communication. Human organs obviously have color, but the underlying biologic processes that dictate the specific colors of organs and tissues are not completely understood. A literature search on the determinants of color in human organs yielded scant information. - To address 2 specific questions: (1) why do human organs have color, and (2) what gives normal and pathologic tissues their distinctive colors? - Endogenous colors are the result of complex biochemical reactions that produce biologic pigments: red-brown cytochromes and porphyrins (blood, liver, spleen, kidneys, striated muscle), brown-black melanins (skin, appendages, brain nuclei), dark-brown lipochromes (aging organs), and colors that result from tissue structure (tendons, aponeurosis, muscles). Yellow-orange carotenes that deposit in lipid-rich tissues are only produced by plants and are acquired from the diet. However, there is lack of information about the cause of color in other organs, such as the gray and white matter, neuroendocrine organs, and white tissues (epithelia, soft tissues). Neoplastic tissues usually retain the color of their nonneoplastic counterpart. - Most available information on the function of pigments comes from studies in plants, microorganisms, cephalopods, and vertebrates, not humans. Biologic pigments have antioxidant and cytoprotective properties and should be considered as potential future therapies for disease and cancer. We discuss the bioproducts that may be responsible for organ coloration and invite pathologists and pathology residents to look at a "routine grossing day" with a different perspective.

Tritium content in tissue free water of Japanese bodies

Energy Technology Data Exchange (ETDEWEB)

Ujeno, Y.; Yamamoto, K.; Aoki, T.; Kurihara, N.

1986-01-01

The tritium content of tissue free water was measured in fresh, non-diseased organs (brain, lungs, liver, kidneys and muscle) removed by forensic autopsy from 4 male and 4 female bodies. Tissue free water was extracted by freeze drying and distillation and tritium measured in the absence of background radon gas. A typical count was approximately 2.70 cpm. The mean tritium content of tissue free water in all the organs examined was 2.50 + - 0.67 Bq.1/sup -1/ (67.6 + -18.2 pCi1/sup -1/). This value was much lower than that obtained for tissues from Italian bodies: the value was, however, similar to that obtained for tap water (70.2 + -28.0 pCi.1/sup -1/), rain water (77.8 + - 47.4 pCi.1/sup -1/) and tissue free water of foods (55.6 + - 26.2 pCi.1/sup -1/).

Microengineered physiological biomimicry: organs-on-chips.

Science.gov (United States)

Huh, Dongeun; Torisawa, Yu-suke; Hamilton, Geraldine A; Kim, Hyun Jung; Ingber, Donald E

2012-06-21

Microscale engineering technologies provide unprecedented opportunities to create cell culture microenvironments that go beyond current three-dimensional in vitro models by recapitulating the critical tissue-tissue interfaces, spatiotemporal chemical gradients, and dynamic mechanical microenvironments of living organs. Here we review recent advances in this field made over the past two years that are focused on the development of 'Organs-on-Chips' in which living cells are cultured within microfluidic devices that have been microengineered to reconstitute tissue arrangements observed in living organs in order to study physiology in an organ-specific context and to develop specialized in vitro disease models. We discuss the potential of organs-on-chips as alternatives to conventional cell culture models and animal testing for pharmaceutical and toxicology applications. We also explore challenges that lie ahead if this field is to fulfil its promise to transform the future of drug development and chemical safety testing.

Measurement of the 234U/238U activity ratios in the organs and internal tissues of a domestic goat kid (Capra aegagrus hircus)

International Nuclear Information System (INIS)

Francesco De Santis; Massimo Esposito

2015-01-01

In this paper, we compare the 234 U/ 238 U activity ratios (ARs) in various internal tissues and organs of a goat kid with the ingested 234 U/ 238 U AR to assess isotopic fractionation. The results obtained from soft tissues (i.e., the kidneys, liver, lung, and bladder) that undergo indirect assimilation of uranium from the feed through the bloodstream suggest an increase in the 234 U/ 238 U AR. In contrast, the intestine, bones and feces had the same AR values as the feed. Finally, we broadly assess uranium transfer from the feed to the animal based on the concentration ratio and the feed transfer coefficient. (author)

Crossroads of Wnt and Hippo in epithelial tissues.

Science.gov (United States)

Bernascone, Ilenia; Martin-Belmonte, Fernando

2013-08-01

Epithelial tissues undergo constant growth and differentiation during embryonic development and to replace damaged tissue in adult organs. These processes are governed by different signaling pathways that ultimately control the expression of genes associated with cell proliferation, patterning, and death. One essential pathway is Wnt, which controls tubulogenesis in several epithelial organs. Recently, Wnt has been closely linked to other signaling pathways, such as Hippo, that orchestrate proliferation and apoptosis to control organ size. There is evidence that epithelial cell junctions may sequester the transcription factors that act downstream of these signaling pathways, which would represent an important aspect of their functional regulation and their influence on cell behavior. Here, we review the transcriptional control exerted by the Wnt and Hippo signaling pathways during epithelial growth, patterning, and differentiation and recent advances in understanding of the regulation and crosstalk of these pathways in epithelial tissues. Copyright © 2013 Elsevier Ltd. All rights reserved.

Tissue engineering: state of the art in oral rehabilitation.

Science.gov (United States)

Scheller, E L; Krebsbach, P H; Kohn, D H

2009-05-01

More than 85% of the global population requires repair or replacement of a craniofacial structure. These defects range from simple tooth decay to radical oncologic craniofacial resection. Regeneration of oral and craniofacial tissues presents a formidable challenge that requires synthesis of basic science, clinical science and engineering technology. Identification of appropriate scaffolds, cell sources and spatial and temporal signals (the tissue engineering triad) is necessary to optimize development of a single tissue, hybrid organ or interface. Furthermore, combining the understanding of the interactions between molecules of the extracellular matrix and attached cells with an understanding of the gene expression needed to induce differentiation and tissue growth will provide the design basis for translating basic science into rationally developed components of this tissue engineering triad. Dental tissue engineers are interested in regeneration of teeth, oral mucosa, salivary glands, bone and periodontium. Many of these oral structures are hybrid tissues. For example, engineering the periodontium requires growth of alveolar bone, cementum and the periodontal ligament. Recapitulation of biological development of hybrid tissues and interfaces presents a challenge that exceeds that of engineering just a single tissue. Advances made in dental interface engineering will allow these tissues to serve as model systems for engineering other tissues or organs of the body. This review will begin by covering basic tissue engineering principles and strategic design of functional biomaterials. We will then explore the impact of biomaterials design on the status of craniofacial tissue engineering and current challenges and opportunities in dental tissue engineering.

Molecular, cellular, and tissue engineering

CERN Document Server

Bronzino, Joseph D

2015-01-01

Known as the bible of biomedical engineering, The Biomedical Engineering Handbook, Fourth Edition, sets the standard against which all other references of this nature are measured. As such, it has served as a major resource for both skilled professionals and novices to biomedical engineering. Molecular, Cellular, and Tissue Engineering, the fourth volume of the handbook, presents material from respected scientists with diverse backgrounds in molecular biology, transport phenomena, physiological modeling, tissue engineering, stem cells, drug delivery systems, artificial organs, and personalized medicine. More than three dozen specific topics are examined, including DNA vaccines, biomimetic systems, cardiovascular dynamics, biomaterial scaffolds, cell mechanobiology, synthetic biomaterials, pluripotent stem cells, hematopoietic stem cells, mesenchymal stem cells, nanobiomaterials for tissue engineering, biomedical imaging of engineered tissues, gene therapy, noninvasive targeted protein and peptide drug deliver...

Bioprinting toward organ fabrication: challenges and future trends.

Science.gov (United States)

Ozbolat, Ibrahim T; Yu, Yin

2013-03-01

Tissue engineering has been a promising field of research, offering hope for bridging the gap between organ shortage and transplantation needs. However, building three-dimensional (3-D) vascularized organs remains the main technological barrier to be overcome. Organ printing, which is defined as computer-aided additive biofabrication of 3-D cellular tissue constructs, has shed light on advancing this field into a new era. Organ printing takes advantage of rapid prototyping (RP) technology to print cells, biomaterials, and cell-laden biomaterials individually or in tandem, layer by layer, directly creating 3-D tissue-like structures. Here, we overview RP-based bioprinting approaches and discuss the current challenges and trends toward fabricating living organs for transplant in the near future.

Bioprinting of hybrid tissue constructs with tailorable mechanical properties

Energy Technology Data Exchange (ETDEWEB)

Schuurman, W; Khristov, V; Pot, M W; Dhert, W J A; Malda, J [Department of Orthopaedics, University Medical Center Utrecht (Netherlands); Van Weeren, P R, E-mail: j.malda@umcutrecht.nl [Faculty of Veterinary Sciences, Department of Equine Sciences, Utrecht University (Netherlands)

2011-06-15

Tissue/organ printing aims to recapitulate the intrinsic complexity of native tissues. For a number of tissues, in particular those of musculoskeletal origin, adequate mechanical characteristics are an important prerequisite for their initial handling and stability, as well as long-lasting functioning. Hence, organized implants, possessing mechanical characteristics similar to the native tissue, may result in improved clinical outcomes of regenerative approaches. Using a bioprinter, grafts were constructed by alternate deposition of thermoplastic fibers and (cell-laden) hydrogels. Constructs of different shapes and sizes were manufactured and mechanical properties, as well as cell viability, were assessed. This approach yields novel organized viable hybrid constructs, which possess favorable mechanical characteristics, within the same range as those of native tissues. Moreover, the approach allows the use of multiple hydrogels and can thus produce constructs containing multiple cell types or bioactive factors. Furthermore, since the hydrogel is supported by the thermoplastic material, a broader range of hydrogel types can be used compared to bioprinting of hydrogels alone. In conclusion, we present an innovative and versatile approach for bioprinting, yielding constructs of which the mechanical stiffness provided by thermoplastic polymers can potentially be tailored, and combined specific cell placement patterns of multiple cell types embedded in a wide range of hydrogels. (communication)

Bioprinting of hybrid tissue constructs with tailorable mechanical properties

International Nuclear Information System (INIS)

Schuurman, W; Khristov, V; Pot, M W; Dhert, W J A; Malda, J; Van Weeren, P R

2011-01-01

Tissue/organ printing aims to recapitulate the intrinsic complexity of native tissues. For a number of tissues, in particular those of musculoskeletal origin, adequate mechanical characteristics are an important prerequisite for their initial handling and stability, as well as long-lasting functioning. Hence, organized implants, possessing mechanical characteristics similar to the native tissue, may result in improved clinical outcomes of regenerative approaches. Using a bioprinter, grafts were constructed by alternate deposition of thermoplastic fibers and (cell-laden) hydrogels. Constructs of different shapes and sizes were manufactured and mechanical properties, as well as cell viability, were assessed. This approach yields novel organized viable hybrid constructs, which possess favorable mechanical characteristics, within the same range as those of native tissues. Moreover, the approach allows the use of multiple hydrogels and can thus produce constructs containing multiple cell types or bioactive factors. Furthermore, since the hydrogel is supported by the thermoplastic material, a broader range of hydrogel types can be used compared to bioprinting of hydrogels alone. In conclusion, we present an innovative and versatile approach for bioprinting, yielding constructs of which the mechanical stiffness provided by thermoplastic polymers can potentially be tailored, and combined specific cell placement patterns of multiple cell types embedded in a wide range of hydrogels. (communication)

TISSUE BANKING – A NEW HOPE FOR RENERATIVE MEDICINE

Directory of Open Access Journals (Sweden)

Mihail George Man

2013-12-01

Full Text Available Cells, tissues and organs banks are specialised facilities in hospitals or medical institutions performing processing, preservation, banking and distribution activities of human morphological components. The authorisation criterias of such facilities are established according to the legislation regarding the human cells, tissues and organs transplantation (the law no. 48/2008 of the Romanian Parliament. Those „cells and tissues banks” are obliged to respect the instructions reguardind the donation, testing, processing, storage, distribution, encoding and trasability of the tissues and cells of human origin, used for therapeutical purposes, as well as the notification of the severe accidents and side effects during the transplantation process. The prelevation, embeding, labeling and transportation of human cells and tissues are performed according to the technical specifications in order to minimise the risk of biological contamination and only after obtaining the informed consent of the living donor and strictely respecting the legal aspects on the decesed donor.

Impact of organic hydroperoxides on rat testicular tissue and ...

African Journals Online (AJOL)

The effects of hydroperoxides on testicular tissue and epididymal sperm were investigated. Male Wistar rats aged 10 - 12 weeks were randomly placed in groups and received standard rat chow and water ad libitum. Animals were injected intraperitoneally with saline (0.5 ml), t-butyl hydroperoxide (5, 10, 20 and 40 ìM; 0.5 ...

The use of microtechnology and nanotechnology in fabricating vascularized tissues.

Science.gov (United States)

Obregón, Raquel; Ramón-Azcón, Javier; Ahadian, Samad; Shiku, Hitoshi; Bae, Hojae; Ramalingam, Murugan; Matsue, Tomokazu

2014-01-01

Tissue engineering (TE) is a multidisciplinary research area that combines medicine, biology, and material science. In recent decades, microtechnology and nanotechnology have also been gradually integrated into this field and have become essential components of TE research. Tissues and complex organs in the body depend on a branched blood vessel system. One of the main objectives for TE researchers is to replicate this vessel system and obtain functional vascularized structures within engineered tissues or organs. With the help of new nanotechnology and microtechnology, significant progress has been made. Achievements include the design of nanoscale-level scaffolds with new functionalities, development of integrated and rapid nanotechnology methods for biofabrication of vascular tissues, discovery of new composite materials to direct differentiation of stem and inducible pluripotent stem cells into the vascular phenotype. Although numerous challenges to replicating vascularized tissue for clinical uses remain, the combination of these new advances has yielded new tools for producing functional vascular tissues in the near future.

Three-dimensional bioprinting in tissue engineering and regenerative medicine.

Science.gov (United States)

Gao, Guifang; Cui, Xiaofeng

2016-02-01

With the advances of stem cell research, development of intelligent biomaterials and three-dimensional biofabrication strategies, highly mimicked tissue or organs can be engineered. Among all the biofabrication approaches, bioprinting based on inkjet printing technology has the promises to deliver and create biomimicked tissue with high throughput, digital control, and the capacity of single cell manipulation. Therefore, this enabling technology has great potential in regenerative medicine and translational applications. The most current advances in organ and tissue bioprinting based on the thermal inkjet printing technology are described in this review, including vasculature, muscle, cartilage, and bone. In addition, the benign side effect of bioprinting to the printed mammalian cells can be utilized for gene or drug delivery, which can be achieved conveniently during precise cell placement for tissue construction. With layer-by-layer assembly, three-dimensional tissues with complex structures can be printed using converted medical images. Therefore, bioprinting based on thermal inkjet is so far the most optimal solution to engineer vascular system to the thick and complex tissues. Collectively, bioprinting has great potential and broad applications in tissue engineering and regenerative medicine. The future advances of bioprinting include the integration of different printing mechanisms to engineer biphasic or triphasic tissues with optimized scaffolds and further understanding of stem cell biology.

Local stem cell depletion model for normal tissue damage

International Nuclear Information System (INIS)

Yaes, R.J.; Keland, A.

1987-01-01

The hypothesis that radiation causes normal tissue damage by completely depleting local regions of tissue of viable stem cells leads to a simple mathematical model for such damage. In organs like skin and spinal cord where destruction of a small volume of tissue leads to a clinically apparent complication, the complication probability is expressed as a function of dose, volume and stem cell number by a simple triple negative exponential function analogous to the double exponential function of Munro and Gilbert for tumor control. The steep dose response curves for radiation myelitis that are obtained with our model are compared with the experimental data for radiation myelitis in laboratory rats. The model can be generalized to include other types or organs, high LET radiation, fractionated courses of radiation, and cases where an organ with a heterogeneous stem cell population receives an inhomogeneous dose of radiation. In principle it would thus be possible to determine the probability of tumor control and of damage to any organ within the radiation field if the dose distribution in three dimensional space within a patient is known

3D Bioprinting for Organ Regeneration.

Science.gov (United States)

Cui, Haitao; Nowicki, Margaret; Fisher, John P; Zhang, Lijie Grace

2017-01-01

Regenerative medicine holds the promise of engineering functional tissues or organs to heal or replace abnormal and necrotic tissues/organs, offering hope for filling the gap between organ shortage and transplantation needs. Three-dimensional (3D) bioprinting is evolving into an unparalleled biomanufacturing technology due to its high-integration potential for patient-specific designs, precise and rapid manufacturing capabilities with high resolution, and unprecedented versatility. It enables precise control over multiple compositions, spatial distributions, and architectural accuracy/complexity, therefore achieving effective recapitulation of microstructure, architecture, mechanical properties, and biological functions of target tissues and organs. Here we provide an overview of recent advances in 3D bioprinting technology, as well as design concepts of bioinks suitable for the bioprinting process. We focus on the applications of this technology for engineering living organs, focusing more specifically on vasculature, neural networks, the heart and liver. We conclude with current challenges and the technical perspective for further development of 3D organ bioprinting. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Organic preservation of fossil musculature with ultracellular detail.

Science.gov (United States)

McNamara, Maria; Orr, Patrick J; Kearns, Stuart L; Alcalá, Luis; Anadón, Pere; Peñalver-Mollá, Enrique

2010-02-07

The very labile (decay-prone), non-biomineralized, tissues of organisms are rarely fossilized. Occurrences thereof are invaluable supplements to a body fossil record dominated by biomineralized tissues, which alone are extremely unrepresentative of diversity in modern and ancient ecosystems. Fossil examples of extremely labile tissues (e.g. muscle) that exhibit a high degree of morphological fidelity are almost invariably replicated by inorganic compounds such as calcium phosphate. There is no consensus as to whether such tissues can be preserved with similar morphological fidelity as organic remains, except when enclosed inside amber. Here, we report fossilized musculature from an approximately 18 Myr old salamander from lacustrine sediments of Ribesalbes, Spain. The muscle is preserved organically, in three dimensions, and with the highest fidelity of morphological preservation yet documented from the fossil record. Preserved ultrastructural details include myofilaments, endomysium, layering within the sarcolemma, and endomysial circulatory vessels infilled with blood. Slight differences between the fossil tissues and their counterparts in extant amphibians reflect limited degradation during fossilization. Our results provide unequivocal evidence that high-fidelity organic preservation of extremely labile tissues is not only feasible, but likely to be common. This is supported by the discovery of similarly preserved tissues in the Eocene Grube Messel biota.

Growing tissues in real and simulated microgravity: new methods for tissue engineering.

Science.gov (United States)

Grimm, Daniela; Wehland, Markus; Pietsch, Jessica; Aleshcheva, Ganna; Wise, Petra; van Loon, Jack; Ulbrich, Claudia; Magnusson, Nils E; Infanger, Manfred; Bauer, Johann

2014-12-01

Tissue engineering in simulated (s-) and real microgravity (r-μg) is currently a topic in Space medicine contributing to biomedical sciences and their applications on Earth. The principal aim of this review is to highlight the advances and accomplishments in the field of tissue engineering that could be achieved by culturing cells in Space or by devices created to simulate microgravity on Earth. Understanding the biology of three-dimensional (3D) multicellular structures is very important for a more complete appreciation of in vivo tissue function and advancing in vitro tissue engineering efforts. Various cells exposed to r-μg in Space or to s-μg created by a random positioning machine, a 2D-clinostat, or a rotating wall vessel bioreactor grew in the form of 3D tissues. Hence, these methods represent a new strategy for tissue engineering of a variety of tissues, such as regenerated cartilage, artificial vessel constructs, and other organ tissues as well as multicellular cancer spheroids. These aggregates are used to study molecular mechanisms involved in angiogenesis, cancer development, and biology and for pharmacological testing of, for example, chemotherapeutic drugs or inhibitors of neoangiogenesis. Moreover, they are useful for studying multicellular responses in toxicology and radiation biology, or for performing coculture experiments. The future will show whether these tissue-engineered constructs can be used for medical transplantations. Unveiling the mechanisms of microgravity-dependent molecular and cellular changes is an up-to-date requirement for improving Space medicine and developing new treatment strategies that can be translated to in vivo models while reducing the use of laboratory animals.

Quantitative characterization of viscoelastic behavior in tissue-mimicking phantoms and ex vivo animal tissues.

Directory of Open Access Journals (Sweden)

Ashkan Maccabi

Full Text Available Viscoelasticity of soft tissue is often related to pathology, and therefore, has become an important diagnostic indicator in the clinical assessment of suspect tissue. Surgeons, particularly within head and neck subsites, typically use palpation techniques for intra-operative tumor detection. This detection method, however, is highly subjective and often fails to detect small or deep abnormalities. Vibroacoustography (VA and similar methods have previously been used to distinguish tissue with high-contrast, but a firm understanding of the main contrast mechanism has yet to be verified. The contributions of tissue mechanical properties in VA images have been difficult to verify given the limited literature on viscoelastic properties of various normal and diseased tissue. This paper aims to investigate viscoelasticity theory and present a detailed description of viscoelastic experimental results obtained in tissue-mimicking phantoms (TMPs and ex vivo tissues to verify the main contrast mechanism in VA and similar imaging modalities. A spherical-tip micro-indentation technique was employed with the Hertzian model to acquire absolute, quantitative, point measurements of the elastic modulus (E, long term shear modulus (η, and time constant (τ in homogeneous TMPs and ex vivo tissue in rat liver and porcine liver and gallbladder. Viscoelastic differences observed between porcine liver and gallbladder tissue suggest that imaging modalities which utilize the mechanical properties of tissue as a primary contrast mechanism can potentially be used to quantitatively differentiate between proximate organs in a clinical setting. These results may facilitate more accurate tissue modeling and add information not currently available to the field of systems characterization and biomedical research.

Quantitative characterization of viscoelastic behavior in tissue-mimicking phantoms and ex vivo animal tissues.

Science.gov (United States)

Maccabi, Ashkan; Shin, Andrew; Namiri, Nikan K; Bajwa, Neha; St John, Maie; Taylor, Zachary D; Grundfest, Warren; Saddik, George N

2018-01-01

Viscoelasticity of soft tissue is often related to pathology, and therefore, has become an important diagnostic indicator in the clinical assessment of suspect tissue. Surgeons, particularly within head and neck subsites, typically use palpation techniques for intra-operative tumor detection. This detection method, however, is highly subjective and often fails to detect small or deep abnormalities. Vibroacoustography (VA) and similar methods have previously been used to distinguish tissue with high-contrast, but a firm understanding of the main contrast mechanism has yet to be verified. The contributions of tissue mechanical properties in VA images have been difficult to verify given the limited literature on viscoelastic properties of various normal and diseased tissue. This paper aims to investigate viscoelasticity theory and present a detailed description of viscoelastic experimental results obtained in tissue-mimicking phantoms (TMPs) and ex vivo tissues to verify the main contrast mechanism in VA and similar imaging modalities. A spherical-tip micro-indentation technique was employed with the Hertzian model to acquire absolute, quantitative, point measurements of the elastic modulus (E), long term shear modulus (η), and time constant (τ) in homogeneous TMPs and ex vivo tissue in rat liver and porcine liver and gallbladder. Viscoelastic differences observed between porcine liver and gallbladder tissue suggest that imaging modalities which utilize the mechanical properties of tissue as a primary contrast mechanism can potentially be used to quantitatively differentiate between proximate organs in a clinical setting. These results may facilitate more accurate tissue modeling and add information not currently available to the field of systems characterization and biomedical research.

Assembly of cells and vesicles for organ engineering

International Nuclear Information System (INIS)

Taguchi, Tetsushi

2011-01-01

The development of materials and technologies for the assembly of cells and/or vesicles is a key for the next generation of tissue engineering. Since the introduction of the tissue engineering concept in 1993, various types of scaffolds have been developed for the regeneration of connective tissues in vitro and in vivo. Cartilage, bone and skin have been successfully regenerated in vitro, and these regenerated tissues have been applied clinically. However, organs such as the liver and pancreas constitute numerous cell types, contain small amounts of extracellular matrix, and are highly vascularized. Therefore, organ engineering will require the assembly of cells and/or vesicles. In particular, adhesion between cells/vesicles will be required for regeneration of organs in vitro. This review introduces and discusses the key technologies and materials for the assembly of cells/vesicles for organ regeneration. (topical review)

Towards artificial tissue models: past, present, and future of 3D bioprinting.

Science.gov (United States)

Arslan-Yildiz, Ahu; El Assal, Rami; Chen, Pu; Guven, Sinan; Inci, Fatih; Demirci, Utkan

2016-03-01

Regenerative medicine and tissue engineering have seen unprecedented growth in the past decade, driving the field of artificial tissue models towards a revolution in future medicine. Major progress has been achieved through the development of innovative biomanufacturing strategies to pattern and assemble cells and extracellular matrix (ECM) in three-dimensions (3D) to create functional tissue constructs. Bioprinting has emerged as a promising 3D biomanufacturing technology, enabling precise control over spatial and temporal distribution of cells and ECM. Bioprinting technology can be used to engineer artificial tissues and organs by producing scaffolds with controlled spatial heterogeneity of physical properties, cellular composition, and ECM organization. This innovative approach is increasingly utilized in biomedicine, and has potential to create artificial functional constructs for drug screening and toxicology research, as well as tissue and organ transplantation. Herein, we review the recent advances in bioprinting technologies and discuss current markets, approaches, and biomedical applications. We also present current challenges and provide future directions for bioprinting research.

3D bioprinting for engineering complex tissues.

Science.gov (United States)

Mandrycky, Christian; Wang, Zongjie; Kim, Keekyoung; Kim, Deok-Ho

2016-01-01

Bioprinting is a 3D fabrication technology used to precisely dispense cell-laden biomaterials for the construction of complex 3D functional living tissues or artificial organs. While still in its early stages, bioprinting strategies have demonstrated their potential use in regenerative medicine to generate a variety of transplantable tissues, including skin, cartilage, and bone. However, current bioprinting approaches still have technical challenges in terms of high-resolution cell deposition, controlled cell distributions, vascularization, and innervation within complex 3D tissues. While no one-size-fits-all approach to bioprinting has emerged, it remains an on-demand, versatile fabrication technique that may address the growing organ shortage as well as provide a high-throughput method for cell patterning at the micrometer scale for broad biomedical engineering applications. In this review, we introduce the basic principles, materials, integration strategies and applications of bioprinting. We also discuss the recent developments, current challenges and future prospects of 3D bioprinting for engineering complex tissues. Combined with recent advances in human pluripotent stem cell technologies, 3D-bioprinted tissue models could serve as an enabling platform for high-throughput predictive drug screening and more effective regenerative therapies. Copyright © 2015 Elsevier Inc. All rights reserved.

Scalable robotic biofabrication of tissue spheroids

International Nuclear Information System (INIS)

Mehesz, A Nagy; Hajdu, Z; Visconti, R P; Markwald, R R; Mironov, V; Brown, J; Beaver, W; Da Silva, J V L

2011-01-01

Development of methods for scalable biofabrication of uniformly sized tissue spheroids is essential for tissue spheroid-based bioprinting of large size tissue and organ constructs. The most recent scalable technique for tissue spheroid fabrication employs a micromolded recessed template prepared in a non-adhesive hydrogel, wherein the cells loaded into the template self-assemble into tissue spheroids due to gravitational force. In this study, we present an improved version of this technique. A new mold was designed to enable generation of 61 microrecessions in each well of a 96-well plate. The microrecessions were seeded with cells using an EpMotion 5070 automated pipetting machine. After 48 h of incubation, tissue spheroids formed at the bottom of each microrecession. To assess the quality of constructs generated using this technology, 600 tissue spheroids made by this method were compared with 600 spheroids generated by the conventional hanging drop method. These analyses showed that tissue spheroids fabricated by the micromolded method are more uniform in diameter. Thus, use of micromolded recessions in a non-adhesive hydrogel, combined with automated cell seeding, is a reliable method for scalable robotic fabrication of uniform-sized tissue spheroids.

Scalable robotic biofabrication of tissue spheroids

Energy Technology Data Exchange (ETDEWEB)

Mehesz, A Nagy; Hajdu, Z; Visconti, R P; Markwald, R R; Mironov, V [Advanced Tissue Biofabrication Center, Department of Regenerative Medicine and Cell Biology, Medical University of South Carolina, Charleston, SC (United States); Brown, J [Department of Mechanical Engineering, Clemson University, Clemson, SC (United States); Beaver, W [York Technical College, Rock Hill, SC (United States); Da Silva, J V L, E-mail: mironovv@musc.edu [Renato Archer Information Technology Center-CTI, Campinas (Brazil)

2011-06-15

Development of methods for scalable biofabrication of uniformly sized tissue spheroids is essential for tissue spheroid-based bioprinting of large size tissue and organ constructs. The most recent scalable technique for tissue spheroid fabrication employs a micromolded recessed template prepared in a non-adhesive hydrogel, wherein the cells loaded into the template self-assemble into tissue spheroids due to gravitational force. In this study, we present an improved version of this technique. A new mold was designed to enable generation of 61 microrecessions in each well of a 96-well plate. The microrecessions were seeded with cells using an EpMotion 5070 automated pipetting machine. After 48 h of incubation, tissue spheroids formed at the bottom of each microrecession. To assess the quality of constructs generated using this technology, 600 tissue spheroids made by this method were compared with 600 spheroids generated by the conventional hanging drop method. These analyses showed that tissue spheroids fabricated by the micromolded method are more uniform in diameter. Thus, use of micromolded recessions in a non-adhesive hydrogel, combined with automated cell seeding, is a reliable method for scalable robotic fabrication of uniform-sized tissue spheroids.

The Human Tissue Act 2004 and the child donor.

Science.gov (United States)

Baston, Jenny

2009-05-01

In 2001, the inquiry panel appointed to investigate the removal, retention and disposal of human organs and tissues at the Royal Liverpool Children's Hospital published its report. The panel's recommendations led to a new approach to consent for organ removal and storage under the new Human Tissue Act 2004. For child bone marrow donors, the new consent process requires all donor children or their parent to undergo a separate assessment before the bone marrow donation. They must be assessed by an accredited assessor who will submit a recommendation to the Human Tissue Authority for consideration. The unfortunate circumstances highlighted in the inquiry have led to changes to law, practice and culture that are benefiting other children and families.

Tissue-Engineered Skeletal Muscle Organoids for Reversible Gene Therapy

Science.gov (United States)

Vandenburgh, Herman; DelTatto, Michael; Shansky, Janet; Lemaire, Julie; Chang, Albert; Payumo, Francis; Lee, Peter; Goodyear, Amy; Raven, Latasha

1996-01-01

Genetically modified murine skeletal myoblasts were tissue engineered in vitro into organ-like structures (organoids) containing only postmitotic myofibers secreting pharmacological levels of recombinant human growth hormone (rhGH). Subcutaneous organoid Implantation under tension led to the rapid and stable appearance of physiological sera levels of rhGH for up to 12 weeks, whereas surgical removal led to its rapid disappearance. Reversible delivery of bioactive compounds from postimtotic cells in tissue engineered organs has several advantages over other forms of muscle gene therapy.

Vascularization of soft tissue engineering constructs

DEFF Research Database (Denmark)

Pimentel Carletto, Rodrigo