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Sample records for cataracts mechanisms involved

  1. Characterization of molecular mechanisms of in vivo UVR induced cataract.

    Science.gov (United States)

    Galichanin, Konstantin; Talebizadeh, Nooshin; Söderberg, Per

    2012-01-01

    Cataract is the leading cause of blindness in the world (1). The World Health Organization defines cataract as a clouding of the lens of the eye which impedes the transfer of light. Cataract is a multi-factorial disease associated with diabetes, smoking, ultraviolet radiation (UVR), alcohol, ionizing radiation, steroids and hypertension. There is strong experimental (2-4) and epidemiological evidence (5,6) that UVR causes cataract. We developed an animal model for UVR B induced cataract in both anesthetized (7) and non-anesthetized animals (8). The only cure for cataract is surgery but this treatment is not accessible to all. It has been estimated that a delay of onset of cataract for 10 years could reduce the need for cataract surgery by 50% (9). To delay the incidence of cataract, it is needed to understand the mechanisms of cataract formation and find effective prevention strategies. Among the mechanisms for cataract development, apoptosis plays a crucial role in initiation of cataract in humans and animals (10). Our focus has recently been apoptosis in the lens as the mechanism for cataract development (8,11,12). It is anticipated that a better understanding of the effect of UVR on the apoptosis pathway will provide possibilities for discovery of new pharmaceuticals to prevent cataract. In this article, we describe how cataract can be experimentally induced by in vivo exposure to UVR-B. Further RT-PCR and immunohistochemistry are presented as tools to study molecular mechanisms of UVR-B induced cataract. PMID:23222480

  2. Cataracts

    Science.gov (United States)

    ... Training and Jobs Home > Statistics and Data > Cataracts Cataracts Listen Language English Cataracts Defined A cataract is a clouding of the ... 2010 2010 U.S. Age-Specific Prevalence Rates for Cataract by Age, and Race/Ethnicity The risk of ...

  3. Cataract

    Science.gov (United States)

    A cataract is a clouding of the lens in your eye. It affects your vision. Cataracts are very common in older people. By age ... than half of all Americans either have a cataract or have had cataract surgery. A cataract can ...

  4. Cataract.

    Science.gov (United States)

    Lam, Dennis; Rao, Srinivas K; Ratra, Vineet; Liu, Yizhi; Mitchell, Paul; King, Jonathan; Tassignon, Marie-José; Jonas, Jost; Pang, Chi P; Chang, David F

    2015-01-01

    Cataract is the leading cause of reversible blindness and visual impairment globally. Blindness from cataract is more common in populations with low socioeconomic status and in developing countries than in developed countries. The only treatment for cataract is surgery. Phacoemulsification is the gold standard for cataract surgery in the developed world, whereas manual small incision cataract surgery is used frequently in developing countries. In general, the outcomes of surgery are good and complications, such as endophthalmitis, often can be prevented or have good ouctomes if properly managed. Femtosecond laser-assisted cataract surgery, an advanced technology, can automate several steps; initial data show no superiority of this approach over current techniques, but the results of many large clinical trials are pending. The greatest challenge remains the growing 'backlog' of patients with cataract blindness in the developing world because of lack of access to affordable surgery. Efforts aimed at training additional cataract surgeons in these countries do not keep pace with the increasing demand associated with ageing population demographics. In the absence of strategie that can prevent or delay cataract formation, it is important to focus efforts and resources on developing models for efficient delivery of cataract surgical services in underserved regions. For an illustrated summary of this Primer, visit: http://go.nature.com/eQkKll. PMID:27188414

  5. Cytoprotective mechanism of action of curcumin against cataract.

    Science.gov (United States)

    Raman, Thiagarajan; Ramar, Manikandan; Arumugam, Munusamy; Nabavi, Seyed Mohammad; Varsha, Mosur Kumaraswamy Nagarajan Sai

    2016-06-01

    This review discusses the relationship between oxidative stress and cataract formation, molecular mechanism of curcumin action and potential benefits of treatment with the antioxidant curcumin. The first section deals with curcumin and endogenous antioxidants. The second section focuses on the action of curcumin on lipid peroxidation. Calcium homeostasis and curcumin will be discussed in the third section. The fourth section discusses the role of crystallin proteins that are responsible for maintaining lens transparency and the role of curcumin in regulating crystallin expression. The interaction of curcumin with transcription factors will be dealt in the fifth section. The final section will focus on the effect of curcumin on aldose reductase, which is associated with hyperglycemia and cataract. One of the strongest antioxidants is curcumin which has been shown to be very effective against cataract. This compound is better than other antioxidants in preventing cataract but its limited bioavailability can be addressed by employing nanotechnology. PMID:26894964

  6. Understanding Cataract Risk in Aerospace Flight Crew And Review of Mechanisms of Cataract Formation

    Science.gov (United States)

    Jones, Jeffrey A.; McCarten, M.; Manuel, K.; Djojonegoro, B.; Murray, J.; Cucinotta, F.; Feiversen, A.; Wear, M.

    2006-01-01

    Induction of cataracts by occupational exposure in flight crew has been an important topic of interest in aerospace medicine in the past five years, in association with numerous reports of flight-associated disease incidences. Due to numerous confounding variables, it has been difficult to determine if there is increased cataract risk directly caused by interaction with the flight environment, specifically associated with added radiation exposure during flight. Military aviator records from the United States Air Force (USAF) and Navy (USN) and US astronauts at the National Aeronautics and Space Administration (NASA)/Lyndon B. Johnson Space Center (JSC) were evaluated for the presence, location and age of diagnosis of cataracts. Military aviators were found to have a statistically significant younger average age of onset of their cataracts compared with astronauts, however the incidence density of cataracts was found to be statistically higher in astronauts than in military aviators. USAF and USN aviator s cataracts were most commonly located in the posterior subcapsular region of the lens while astronauts cataracts were most likely to originate generally in the cortical zone. A prospective clinical trial which controls for confounding variables in examination technique, cataract classification, diet, exposure, and pharmacological intervention is needed to determine what percentage of the risk for cataracts are due to radiation, and how to best develop countermeasures to protect flight crews from radiation bioeffects in the future.

  7. Medico-legal implications of traumatic cataract.

    Science.gov (United States)

    Moreschi, Carlo; Da Broi, Ugo; Lanzetta, Paolo

    2013-02-01

    Traumatic cataract is due to lens damage when mechanical, irradiative, electrical or chemical agents injury the globe. The appearance of a traumatic cataract is typically short and unilateral with rare spontaneous resolution and often involves other ocular anatomical areas. Medico-legal evaluation of the appearance and the consequences of a traumatic cataract requires a correct methodological approach with the support of qualified ophthalmological competences. PMID:23357390

  8. Cataract Vision Simulator

    Science.gov (United States)

    ... for Cataracts? Cataract Causes Cataract Diagnosis Cataract Treatment Cataract Surgery IOL Implants: Lens Replacement and Cataract Surgery Cataract Vision Simulator Cataract Vision Simulator Jun. 11, ...

  9. Cataract (image)

    Science.gov (United States)

    A cataract is a cloudy or opaque area in the lens of the eye. Cataracts usually develop as a person gets older and ... substances can also accelerate the development of a cataract. Cataracts can cause visual problems such as difficulty ...

  10. Investigation of lens morphology and mechanical characteristics of lens capsule and lens nucleus in patients with agerelated and diabetic cataract

    Directory of Open Access Journals (Sweden)

    A. S. Tishkova

    2014-07-01

    Full Text Available Purpose: To investigate the influence of carbohydrate metabolism on the structure and mechanical properties of the lens capsule and nucleus.Methods: Human lens pathology was studied in different forms of cataract. 220 patients with a cataract (220 eyes were included in this study. Morphological, immunohystological and immunocytochemical investigations of lens substance (antibodies to a- (a-А and a-В, b-, g- crystallines, spectroscopic analyses of smears and morphometric analyses of slices, investigation of lens morphology and mechanical caracteristics of lens capsule and lens nucleus were performed.Results: The capsule of the lens in patients with senile cataract contains more Na+, Cl-. The capsule of the lens in patients with senile cataract contains more Ca2+, O. Mechanical strength of the capsule in the case of diabetes mellitus was lower comparatively with senile cataract in the same age groups. More significant expression of a-В and b-crystallines was found in patients with diabetes mellitus comparatively with patients with age-related cataract. Morphological features were founded in patients with cortical and nuclear forms of senile cataract and the diabetic cataract.Conclusion: During surgery (ultrasonic microcoaxial phacoemulsification the equivalent of ultrasound was recorded. Lower density of the lens nucleus of patients with diabetes mellitus made it possible to use lower energy parameters. Using the torsion ultrasound in those cases allowed us to decrease the influence of ultrasound on eye tissues and reduce the time of achieving the maximum BCVA in the postsurgical period.

  11. Cataract - adult

    Science.gov (United States)

    ... home to avoid falls and injuries. The only treatment for a cataract is surgery to remove it. If a cataract ... Early diagnosis and treatment are key to preventing permanent ... a hypermature cataract) can begin to leak into other parts of ...

  12. In vitro unfolding, refolding, and polymerization of human gammaD crystallin, a protein involved in cataract formation.

    Science.gov (United States)

    Kosinski-Collins, Melissa S; King, Jonathan

    2003-03-01

    Human gammaD crystallin (HgammaD-Crys), a major protein of the human eye lens, is a primary component of cataracts. This 174-residue primarily beta-sheet protein is made up of four Greek keys separated into two domains. Mutations in the human gene sequence encoding HgammaD-Crys are implicated in early-onset cataracts in children, and the mutant protein expressed in Escherichia coli exhibits properties that reflect the in vivo pathology. We have characterized the unfolding, refolding, and competing aggregation of human wild-type HgammaD-Crys as a function of guanidinium hydrochloride (GuHCl) concentration at neutral pH and 37 degrees C, using intrinsic tryptophan fluorescence to monitor in vitro folding. Wild-type HgammaD-Crys exhibited reversible refolding above 1.0 M GuHCl. The GuHCl unfolded protein was more fluorescent than its native counterpart despite the absence of metal or ion-tryptophan interactions. Aggregation of refolding intermediates of HgammaD-Crys was observed in both equilibrium and kinetic refolding processes. The aggregation pathway competed with productive refolding at denaturant concentrations below 1.0 M GuHCl, beyond the major conformational transition region. Atomic force microscopy of samples under aggregating conditions revealed the sequential appearance of small nuclei, thin protofibrils, and fiber bundles. The HgammaD-Crys fibrous aggregate species bound bisANS appreciably, indicating the presence of exposed hydrophobic pockets. The mechanism of HgammaD-Crys aggregation may provide clues to understanding age-onset cataract formation in vivo. PMID:12592018

  13. Radiation cataract

    International Nuclear Information System (INIS)

    Until very recently, ocular exposure guidelines were based on the assumption that radiation cataract is a deterministic event requiring threshold doses generally greater than 2 Gy. This view was, in part, based on older studies which generally had short follow-up periods, failed to take into account increasing latency as dose decreased, had relatively few subjects with doses below a few Gy, and were not designed to detect early lens changes. Newer findings, including those in populations exposed to much lower radiation doses and in subjects as diverse as astronauts, medical workers, atomic bomb survivors, accidentally exposed individuals, and those undergoing diagnostic or radiotherapeutic procedures, strongly suggest dose-related lens opacification at significantly lower doses. These observations resulted in a recent re-evaluation of current lens occupational exposure guidelines, and a proposed lowering of the presumptive radiation cataract threshold to 0.5 Gy/year and the occupational lens exposure limit to 20 mSv/year, regardless of whether received as an acute, protracted, or chronic exposure. Experimental animal studies support these conclusions and suggest a role for genotoxicity in the development of radiation cataract. Recent findings of a low or even zero threshold for radiation-induced lens opacification are likely to influence current research efforts and directions concerning the cellular and molecular mechanisms underlying this pathology. Furthermore, new guidelines are likely to have significant implications for occupational and/or accidental exposure, and the need for occupational eye protection (e.g. in fields such as interventional medicine).

  14. The myosin chaperone UNC45B is involved in lens development and autosomal dominant juvenile cataract

    DEFF Research Database (Denmark)

    Hansen, Lars; Comyn, Sophie; Mang, Yuan;

    2014-01-01

    -type embryos resulted in development of a phenotype similar to the steif mutant. The p.Arg805Trp alteration in the mammalian UNC45B gene suggests that developmental cataract may be caused by a defect in non-muscle myosin assembly during maturation of the lens fiber cells.European Journal of Human Genetics...... in myosin assembly. The mutation changes p.Arg805 to Trp in the UCS domain, an amino acid that is highly conserved from yeast to human. UNC45B is strongly expressed in the heart and skeletal muscle tissue, but here we show expression in human embryo eye and zebrafish lens. The zebrafish mutant steif......, carrying an unc45b nonsense mutation, has smaller eyes than wild-type embryos and shows accumulation of nuclei in the lens. Injection of RNA encoding the human wild-type UNC45B protein into the steif homozygous embryo reduced the nuclei accumulation and injection of human mutant UNC45B cDNA in wild...

  15. Cataract and Cataract Surgery: Nationwide Prevalence and Clinical Determinants.

    Science.gov (United States)

    Park, Sang Jun; Lee, Ju Hyun; Kang, Se Woong; Hyon, Joon Young; Park, Kyu Hyung

    2016-06-01

    This study aimed to investigate the prevalence and clinical determinants of cataract and cataract surgery in Korean population. The 2008-2012 Korean National Health and Nutrition Examination Survey was analyzed, which included 20,419 participants aged ≥ 40 years. The survey is a multistage, probability-cluster survey, which can produce nationally representative estimates. Prevalence of cataract and cataract surgery was estimated. Clinical determinants for those were investigated using logistic regression analyses (LRAs). The prevalence of cataract was 42.28% (95% confidence interval [CI], 40.67-43.89); 40.82% (95% CI, 38.97-42.66) for men and 43.62% (95% CI, 41.91-45.33) for women (P = 0.606). The prevalence of cataract surgery was 7.75% (95% CI, 7.30-8.20); 6.38% (95% CI, 5.80-6.96) for men and 9.01% (95% CI, 8.41-9.61) for women (P Cataract was associated with older age (P Cataract surgery was consistently associated with older age, occupation, DM, asthma, and anemia in two LRAs, which compared participants with cataract surgery to those without cataract surgery and those having a cataract but without any cataract surgery, respectively. Hypertension, arthritis, and dyslipidemia were associated with cataract surgery at least in one of these LRAs. These results suggest that there are 9.4 million individuals with cataract and 1.7 million individuals with cataract surgery in Korea. Further studies are warranted to reveal the causality and its possible mechanism of developing/exacerbating cataract in novel determinants (i.e., anemia, asthma, and arthritic conditions) as well as well-known determinants. PMID:27247507

  16. Cataract removal

    Science.gov (United States)

    ... the following ways, depending on the type of cataract: Phacoemulsification: With this procedure, the doctor uses a tool that produces sound waves to break up the cataract into small pieces. The pieces are then suctioned ...

  17. Cataract surgery to lower intraocular pressure

    Directory of Open Access Journals (Sweden)

    Berdahl John

    2009-01-01

    Full Text Available Cataract and glaucoma are common co morbidities. Cataract surgery is frequently performed in patients with glaucoma. In this study, a review of literature with search terms of cataract, glaucoma and intraocular pressure is followed by evaluation and synthesis of data to determine the effect of cataract surgery on intraocular pressure. Cataract surgery seems to lower intraocular pressure on a sustained basis, especially in patients with higher preoperative intraocular pressure. The mechanism of action of these finds remains speculative.

  18. Cataract Surgery Tool

    Science.gov (United States)

    1977-01-01

    The NASA-McGannon cataract surgery tool is a tiny cutter-pump which liquefies and pumps the cataract lens material from the eye. Inserted through a small incision in the cornea, the tool can be used on the hardest cataract lens. The cutter is driven by a turbine which operates at about 200,000 revolutions per minute. Incorporated in the mechanism are two passages for saline solutions, one to maintain constant pressure within the eye, the other for removal of the fragmented lens material and fluids. Three years of effort have produced a design, now being clinically evaluated, with excellent potential for improved cataract surgery. The use of this tool is expected to reduce the patient's hospital stay and recovery period significantly.

  19. There will be early- and late-onset radiation cataracts that may arise by different pathomechanisms

    International Nuclear Information System (INIS)

    A cataract is a clouding of the crystalline lens of the eye. Radiation cataract has been known for over a century, but its underlying mechanisms remain incompletely understood. In 2011, the International Commission on Radiological Protection (ICRP) issued the Seoul Statement to lower the dose threshold for vision-impairing cataract. ICRP deduced its acute threshold from epidemiological evidence demonstrating zero threshold, but concluded that cataract is a tissue reaction with a threshold albeit small. This paper is the first to hypothesize that there will be early- and late-onset cataracts that may arise by different pathomechanisms, and discusses this hypothesis according to available epidemiological and biological evidence. On one hand, early-onset posterior subcapsular cataract (PSC) may arise with a threshold after acute exposure. On the other, late-onset PSC or cortical cataract may arise without threshold after exposure regardless of the rate of dose delivery. Early-onset PSC may be attributable to excessive proliferation of lens epithelial cells, and late-onset PSC may involve its impaired proliferation. Late-onset cortical cataract may be associated with acceleration of aging process. If this hypothesis holds true, cataract will be a tissue reaction as well as a stochastic effect, challenging the current framework to classify radiation effects into these two categories. (author)

  20. Natural and radiation-induced cataracts in man and mouse, and natural macular degeneration in man: proposed mechanisms

    International Nuclear Information System (INIS)

    A unified theory of growth and age-dependent disorders is applied to the interpretation of epidemiological data for natural and radiation-induced cataracts and natural macular degeneration in man. Using the same unified theory, mechanisms are also proposed to explain the experimental evidence for natural and radiation-induced lenticular opacities in the lens of the mouse. Epidemiological and experimental data are strikingly consistent with the hypothesis that natural cataract formation is an autoaggressive process but the details of pathogenesis differ greatly between the two species. Radiation dose-response relations reflect these contrasts.. Lenticular opacities in the nuclear-bomb survivors at Hiroshima and Nagasaki were probably induced by a 'single-track' mechanism. Radiation-induced generalised opacification in the lens of the mouse results from a 'multi-track' process. The pathogenesis of natural macular degeneration in man happens to have close parallels with that of natural opacification in the mouse. Some implications of these inferences for the phenomenon of radiation-induced lethal disorders in man are discussed. (author)

  1. Recognizing Cataracts

    Science.gov (United States)

    ... please review our exit disclaimer . Subscribe Recognizing Cataracts Watch for Vision Changes as You Age As life ... your eyes from harmful ultraviolet rays from the sun. Try wearing sunglasses or a hat with a ...

  2. Reversible Cataract as the Presenting Sign of Diabetes Mellitus: Report of Two Cases and Literature Review

    Directory of Open Access Journals (Sweden)

    Xiu Min Wang

    2012-03-01

    Full Text Available Background: Type 1 diabetes mellitus (T1DM is the most common form of diabetes in young children. Serious optic complications, e.g. diabetic retinopathy and diabetic cataract involvement, are not usually detected in T1DM patients at the onset of the disease.Case Presentation: Two girls aged 11 years and 9 years were hospitalized in our unit in 2008 and 2009. They presented cataracts 1 and 6 months before the diagnosis of T1DM, respectively. After blood glucose level was controlled by insulin therapy, the cataract was resolved, totally in one and partly in the other girl. Meanwhile, visual acuity of both cases recovered, closely associated with fluctuation of plasma glucose level. In this study, we describe the symptoms, probable mechanism and treatment of diabetic cataract.Conclusion: Early antihyperglycemic therapy and maintenance of stable blood glucose level may reverse acute diabetic cataract or prevent it from getting worse.

  3. Mechanisms of cataract development in adult Atlantic salmon growers relative to dietary histidine and plant feed ingredients

    OpenAIRE

    Tröße, Christiane

    2010-01-01

    Cataracts are defined as opacities of the eye lens and can be caused by a large number of risk factors. In aquaculture, cataracts in farmed Atlantic salmon (Salmo salar L.) represent an ethical problem and can cause economical losses. A series of studies have shown the cataract mitigating effect of dietary histidine (His) levels above the currently recommended minimum requirement in Atlantic salmon smolt and that dietary His levels are reflected in the concentrations of the His...

  4. Connexin mutants and cataracts

    Directory of Open Access Journals (Sweden)

    EricCBeyer

    2013-04-01

    Full Text Available The lens is a multicellular, but avascular tissue that must stay transparent to allow normal transmission of light and focusing of it on the retina. Damage to lens cells and/or proteins can cause cataracts, opacities that disrupt these processes. The normal survival of the lens is facilitated by an extensive network of gap junctions formed predominantly of connexin46 and connexin50. Mutations of the genes that encode these connexins (GJA3 and GJA8 have been identified and linked to inheritance of cataracts in human families and mouse lines. In vitro expression studies of several of these mutants have shown that they exhibit abnormalities that may lead to disease. Many of the mutants reduce or modify intercellular communication due to channel alterations (including loss of function or altered gating or due to impaired cellular trafficking which reduces the number of gap junction channels within the plasma membrane. However, the abnormalities detected in studies of other mutants suggest that they cause cataracts through other mechanisms including gain of hemichannel function (leading to cell injury and death and formation of cytoplasmic accumulations (that may act as light scattering particles. These observations and the anticipated results of ongoing studies should elucidate the mechanisms of cataract development due to mutations of lens connexins and abnormalities of other lens proteins. They may also contribute to our understanding of the mechanisms of disease due to connexin mutations in other tissues.

  5. Oxidative stress and age-related cataract

    OpenAIRE

    Zheng Selin, Jinjin

    2015-01-01

    Age-related cataract is a clouding of the lens that leads to decreased vision. It increases with age and is one of the leading causes of blindness worldwide. The only treatment currently available is surgery. Therefore, it is important to identify modifiable risk factors for cataract prevention. The cause of cataract is not fully understood and may be multifactorial, involving oxidative stress, a condition of disrupted balance between oxidants and antioxidants. Oxidative damage to lens protei...

  6. Lanosterol reverses protein aggregation in cataracts.

    Science.gov (United States)

    Zhao, Ling; Chen, Xiang-Jun; Zhu, Jie; Xi, Yi-Bo; Yang, Xu; Hu, Li-Dan; Ouyang, Hong; Patel, Sherrina H; Jin, Xin; Lin, Danni; Wu, Frances; Flagg, Ken; Cai, Huimin; Li, Gen; Cao, Guiqun; Lin, Ying; Chen, Daniel; Wen, Cindy; Chung, Christopher; Wang, Yandong; Qiu, Austin; Yeh, Emily; Wang, Wenqiu; Hu, Xun; Grob, Seanna; Abagyan, Ruben; Su, Zhiguang; Tjondro, Harry Christianto; Zhao, Xi-Juan; Luo, Hongrong; Hou, Rui; Perry, J Jefferson P; Gao, Weiwei; Kozak, Igor; Granet, David; Li, Yingrui; Sun, Xiaodong; Wang, Jun; Zhang, Liangfang; Liu, Yizhi; Yan, Yong-Bin; Zhang, Kang

    2015-07-30

    The human lens is comprised largely of crystallin proteins assembled into a highly ordered, interactive macro-structure essential for lens transparency and refractive index. Any disruption of intra- or inter-protein interactions will alter this delicate structure, exposing hydrophobic surfaces, with consequent protein aggregation and cataract formation. Cataracts are the most common cause of blindness worldwide, affecting tens of millions of people, and currently the only treatment is surgical removal of cataractous lenses. The precise mechanisms by which lens proteins both prevent aggregation and maintain lens transparency are largely unknown. Lanosterol is an amphipathic molecule enriched in the lens. It is synthesized by lanosterol synthase (LSS) in a key cyclization reaction of a cholesterol synthesis pathway. Here we identify two distinct homozygous LSS missense mutations (W581R and G588S) in two families with extensive congenital cataracts. Both of these mutations affect highly conserved amino acid residues and impair key catalytic functions of LSS. Engineered expression of wild-type, but not mutant, LSS prevents intracellular protein aggregation of various cataract-causing mutant crystallins. Treatment by lanosterol, but not cholesterol, significantly decreased preformed protein aggregates both in vitro and in cell-transfection experiments. We further show that lanosterol treatment could reduce cataract severity and increase transparency in dissected rabbit cataractous lenses in vitro and cataract severity in vivo in dogs. Our study identifies lanosterol as a key molecule in the prevention of lens protein aggregation and points to a novel strategy for cataract prevention and treatment. PMID:26200341

  7. Radiation cataract

    International Nuclear Information System (INIS)

    This report reviews the relationship of ionizing radiation to the occurrence of cataracts (posterior lenticular opacities) among the A-bomb survivors in Hiroshima and Nagasaki. The new DS86 doses are available for 1,983 (93.4%) of the 2,124 A-bomb survivors analyzed in 1982. The DS86 kerma neutron component for Hiroshima is much smaller than its comparable T65DR component, but still 4.2 fold higher (0.38 Gy at 6 Gy) than that in Nagasaki (0.09 Gy at 6 Gy). Thus, if the eye is especially sensitive to neutrons, there may yet be some useful information on their effects, particularly in Hiroshima. Under the best fitting dose-response model, an L (gamma)-L (neutron) with two thresholds, both the gamma and neutron regression coefficients of the occurrence of cataracts on dose are positive and highly significant for the DS86 eye organ doses. The DS86 gamma coefficient is almost the same as that associated with the T65DR gamma dose, the ratio of the two coefficients being 1.1 (95% confidence limits: 0.5-2.3) for DS86 kerma in the individual dose data, and if the risks based on the DS86 eye organ dose and DS86 kerma are compared, the ratio is 1.3 (0.6-2.8). However, the risk estimates associated with neutron exposure are 6.4 (2.2-19.2) fold higher for the DS86 kerma than the T65DR kerma and 1.6 (0.5-2.3) fold higher for the DS86 eye organ dose than for the DS86 kerma. (author)

  8. Physiopathologic mechanisms involved in mare endometrosis.

    Science.gov (United States)

    Rebordão, M R; Galvão, A; Szóstek, A; Amaral, A; Mateus, L; Skarzynski, D J; Ferreira-Dias, G

    2014-10-01

    Endometrosis is a degenerative chronic process, characterized by paramount fibrosis development in mare endometrium. This condition is one of the major causes of subfertility/infertility in mares. As in other organs, fibrosis might be a pathologic sequel of many chronic inflammatory diseases. However, aetiology and physiopathologic mechanisms involved in endometrial fibrosis are still controversial. This review presents new hypotheses based on our newest data. As the first line of innate immune defence, systemic neutrophils arrive in the uterus at mating or in the presence of pathogens. A novel paradigm is that neutrophils cast out their DNA in response to infectious stimuli and form neutrophil extracellular traps (NETs). We have shown that bacterial strains of Streptococcus zooepidemicus, Escherichia coli or Staphylococcus capitis, known to cause endometritis in mares were able to induce NETs release in vitro by equine PMN to different extents. An intriguing dilemma is the dual action of NETs. While NETs play a desirable role fighting micro-organisms in mare uterus, they may also contribute to endometrial fibrosis. A long-term in vitro exposure of mare endometrium explants to NETs components (myeloperoxidase, elastase and cathepsin G) up-regulated fibrosis markers TGFβ and Tissue inhibitor of metalloproteinase (TIMP-1). Also, pro-fibrotic cytokines regulated collagen deposition and fibrosis. Changes in expression of connective tissue growth factor (CTGF), interleukins (IL)1-α, IL-1β, IL-6 and receptors in endometrium with different degrees of fibrosis and/or inflammation were observed. A putative role of CTGF, IL and NETs components in endometrosis development should be considered. Additionally, we speculate that in sustained endometritis in mares, prostaglandins may not only cause early luteolysis or early pregnancy loss, but may also be related to endometrial fibrosis pathogenesis by stimulating collagen deposition. PMID:25277436

  9. Recent Advances in Cataract Operations: Phacoemulsification, Intraocular Lens Implantation and Prolonged-Wear Soft Contact Lenses

    OpenAIRE

    Salz, James J.

    1981-01-01

    A standard cataract extraction involves removal of the entire cataractous lens through a 12- to 13-mm incision with the aid of a cryoprobe while phacoemulsification consists of removing the cataract through a 3-mm incision by breaking the lens into small pieces with an ultrasonically vibrating needle which is then used to aspirate the fragmented cataract. Most ophthalmic surgeons choose to carry out the standard cataract extraction because although phacoemulsification offers a more rapid reha...

  10. Cataract surgery - series (image)

    Science.gov (United States)

    Cataract surgery usually works very well. The operation has few risks, the pain and recovery period are short, ... improved. Ninety-five percent or more of all cataract surgeries result in improved vision.

  11. Cataract surgery and intraocular pressure.

    Science.gov (United States)

    Melancia, Diana; Abegão Pinto, Luis; Marques-Neves, Carlos

    2015-01-01

    Cataract surgery is one of the most performed surgeries in the developed world. In addition to its significant impact on visual acuity, phacoemulsification has been hailed as a potential intraocular pressure (IOP)-lowering procedure. While current evidence suggests an overall significant and sustained decrease in IOP to exist after cataract surgery, the specific ocular characteristics that could help predict which patients are likely to benefit from this IOP-lowering effect remain unclear. This definition is important in glaucoma patients if this surgery is to be used in the treatment for this disease. Our review aims to summarize the literature on the subject, depicting possible mechanisms behind this IOP decrease, which type of patients are more likely to benefit from this surgery for IOP-lowering purposes and ultimately help optimizing disease management for the increasing number of patients with concomitant glaucoma and cataract. PMID:25765255

  12. Radiation-induced cataract-genesis: pathophysiologic, radiobiological and clinical aspects

    International Nuclear Information System (INIS)

    Cataract-genesis is a widely reported late effect of irradiated crystalline lens. In this review the authors discussed the different aspects of radiation cataract pathogenesis, and the different mechanisms involved in the lens opacification, particularly the epithelium modifications such as epithelial cell death. The authors also reported the influence of radiation exposure on cataract formation following total body irradiation TBI) and autologous or allogeneic bone marrow transplantation for hematologic malignancies. Moreover, the radiobiological parameters are not studied for the crystalline lens of human. We applied for the first time the linear quadratic (LQ) and biological effective dose (BED) concept to TBI data. The calculated value of α/β of 1 Gy is in the range of the values reported for the other late responding tissues. The other risk factors for cataract development after TBI such as age, gender, central nervous system boost, long-term steroid therapy and heparin administration are discussed. In terms of cataract or sicca syndrome prevention, numerous compounds have been successfully tested in experimental models or used for the prevention of radiation-induced xerostomia in patients treated for head and neck cancer. However, none of them has been clinically evaluated for ocular radiation late effects prevention. In this report the authors discussed some of the radioprotectors potentially interesting for radiation-induced cataract or sicca syndrome prevention. (author)

  13. Mechanisms of cocarcinogenesis involving endogenous retroviruses

    International Nuclear Information System (INIS)

    This review article with 118 references summarizes recent in vivo and in vitro experimental results related to cocarcenogenesis and some potential mechanisms of virus - radiation/chemical carcinogen interactions. The RNA tumor viruses (retroviruses) may disrupt repair synthesis of DNA, thereby serving to indirectly increase the probability that exposure to a carcinogen could result in transformation. Several alternative mechanisms are proposed to explain these interactions

  14. Nutritional modulation of cataract

    Science.gov (United States)

    Cataract, or lens opacification, remains a major cause of blindness worldwide. Cataracts reduce vision in over eighty million people, causing blindness in eighteen million people. The number afflicted by cataract will increase dramatically as the proportion of the elderly global population increase...

  15. Cortisol involvement in mechanisms of behavioral inhibition

    NARCIS (Netherlands)

    Tops, Mattie; Boksem, Maarten A. S.

    2011-01-01

    We studied whether baseline cortisol is associated with post-error slowing, a measure that depends upon brain areas involved in behavioral inhibition. Moreover, we studied whether this association holds after controlling for positive associations with behavioral inhibition scores and error-related n

  16. Involvement of Mechanical Stress in Androgenetic Alopecia

    OpenAIRE

    Tellez-Segura, Rafael

    2015-01-01

    Context: Androgenetic alopecia (AGA) is a frequent disorder characterized by progressive hair miniaturization in a very similar pattern among all affected men. The pathogenesis is related to androgen-inducible overexpression of transforming growth factor β-1 from balding dermal papilla cells, which is involved in epithelial inhibition and perifollicular fibrosis. Recent research shows that hair follicle androgen sensitivity is regulated by Hic-5, an androgen receptor co-activator which may be...

  17. Molecular mechanisms involved in intestinal iron absorption

    Institute of Scientific and Technical Information of China (English)

    Paul Sharp; Surjit Kaila Srai

    2007-01-01

    Iron is an essential trace metal in the human diet due to its obligate role in a number of metabolic processes.In the diet, iron is present in a number of different forms, generally described as haem (from haemoglobin and myoglobin in animal tissue) and non-haem iron (including ferric oxides and salts, ferritin and lactoferrin).This review describes the molecular mechanisms that co-ordinate the absorption of iron from the diet and its release into the circulation. While many components of the iron transport pathway have been elucidated, a number of key issues still remain to be resolved. Future work in this area will provide a clearer picture regarding the transcellular flux of iron and its regulation by dietary and humoral factors.

  18. Mechanisms involved in cellular ceramide homeostasis

    Directory of Open Access Journals (Sweden)

    Hussain M

    2012-07-01

    Full Text Available Abstract Sphingolipids are ubiquitous and critical components of biological membranes. Their biosynthesis starts with soluble precursors in the endoplasmic reticulum and culminates in the Golgi complex and plasma membrane. Ceramides are important intermediates in the biosynthesis of sphingolipids, such as sphingomyelin, and their overload in the membranes is injurious to cells. The major product of ceramide metabolism is sphingomyelin. We observed that sphingomyelin synthase (SMS 1 or SMS2 deficiencies significantly decreased plasma and liver sphingomyelin levels. However, SMS2 but not SMS1 deficiency increased plasma ceramides. Surprisingly, SMS1 deficiency significantly increased glucosylceramide and ganglioside GM3, but SMS2 deficiency did not. To explain these unexpected findings about modest to no significant changes in ceramides and increases in other sphingolipids after the ablation of SMS1, we hypothesize that cells have evolved several organelle specific mechanisms to maintain ceramide homeostasis. First, ceramides in the endoplasmic reticulum membranes are controlled by its export to Golgi by protein mediated transfer. Second, in the Golgi, ceramide levels are modulated by their enzymatic conversion to different sphingolipids such as sphingomyelin, and glucosylceramides. Additionally, these sphingolipids can become part of triglyceride-rich apolipoprotein B-containing lipoproteins and be secreted. Third, in the plasma membrane ceramide levels are maintained by ceramide/sphingomyelin cycle, delivery to lysosomes, and efflux to extracellular plasma acceptors. All these pathways might have evolved to ensure steady cellular ceramide levels.

  19. Glucan: mechanisms involved in its radioprotective effect

    International Nuclear Information System (INIS)

    It has generally been accepted that most biologically derived agents that are radioprotective in the hemopoietic-syndrome dose range (eg, endotoxin, Bacillus Calmette Guerin, Corynebacterium parvum, etc) exert their beneficial properties by enhancing hemopoietic recovery and hence, by regenerating the host's ability to resist life-threatening opportunistic infections. However, using glucan as a hemopoietic stimulant/radioprotectant, we have demonstrated that host resistance to opportunistic infection is enhanced in these mice even prior to the detection of significant hemopoietic regeneration. This early enhanced resistance to microbial invasion in glucan-treated irradiated mice could be correlated with enhanced and/or prolonged macrophage (but not granulocyte) function. These results suggest that early after irradiation glucan may mediate its radioprotection by enhancing resistance to microbial invasion via mechanisms not necessarily predicated on hemopoietic recovery. In addition, preliminary evidence suggests that glucan can also function as an effective free-radical scavenger. Because macrophages have been shown to selectively phagocytize and sequester glucan, the possibility that these specific cells may be protected by virtue of glucan's scavenging ability is also suggested

  20. Facts and Myths about Cataracts

    Science.gov (United States)

    ... Lasers are used to remove cataracts FACT: In cataract treatment, the clouded lens is surgically removed and then ... membrane behind the implant may become cloudy after cataract surgery. Laser treatment then may be used to open up the ...

  1. Surgery for Congenital Cataract

    OpenAIRE

    David Yorston FRCS FRCOphth

    2004-01-01

    The management of congenital cataract is very different to the treatment of a routine age-related cataract. In adults, surgery may be delayed for years without affecting the visual outcome. In infants, if the cataract is not removed during the first year of life, the vision will never be fully regained after surgery. In adults, if the aphakia is not corrected immediately, it can be corrected later. In young children, if the aphakia is not corrected, the vision will never develop normally.

  2. Cataract surgery in uveitis

    OpenAIRE

    Hazari Ajit; Sangwan Virender

    2002-01-01

    Purpose:To study the visual outcome of cataract surgery in eyes with uveitis.Methods: A retrospective analysis of patients with uveitis operated for cataract. Results: 106 eyes of 89 patients with uveitis were operated for cataract. In 62.3% eyes (66/106), post -operative follow-up was at least 6 months. There was significant improvement (P<0.001) in visual acuity after cataract surgery. Provided the uveitis was well controlled for three months pre-operatively, additional pre...

  3. Training a cataract surgeon

    Directory of Open Access Journals (Sweden)

    M Babar Qureshi

    2014-07-01

    Full Text Available Training in cataract surgery is one of the key factors needed to ensure high quality cataract surgery with good visual outcomes and patient satisfaction. The training has to impart the right skills to the right person by the right trainer and in the right environment.

  4. Advances in pharmacological strategies for the prevention of cataract development

    Directory of Open Access Journals (Sweden)

    Gupta S

    2009-01-01

    Full Text Available Cataractous-opacification of the lens is one of the leading causes of blindness in India. The situation can be managed by surgical removal of the cataractous lens. Various pharmacological strategies have been proposed for the prevention and treatment of cataract. Information on possible benefits of putative anticataract agents comes from a variety of approaches, ranging from laboratory experiments, both in vitro and in vivo , to epidemiological studies in patients. This review deals with the various mechanisms, and possible pharmacological interventions for the prevention of cataract. The article also reviews research on potential anticataractous agents, including aldose reductase inhibitors, glutathione boosters, antiglycating agents, vitamins and various drugs from indigenous sources.

  5. Atomic bomb cataracts

    International Nuclear Information System (INIS)

    Eye disturbance caused by atomic bomb radiation can be divided into three groups: direct injury immediately after exposure, eye lesions associated with radiation syndrome, and delayed disturbance. The crystalline lens of the eye is the most radiosensitive. Atomic bomb cataract has been investigated in a number of studies. The first section of this chapter discusses radiation cataract in terms of the incidence and characteristics. The second section deals with atomic bomb cataract, which can be diagnosed based on the four criteria: (1) opacity of the crystalline lens, (2) a history of proximal exposure, (3) lack of eye disease complicating cataract, and (4) non-exposure to radiation other than atomic bombing. The prevalence of cataract and severity of opacity are found to correlate with exposure doses and age at the time of exposure. Furthermore, it is found to correlate with distance from the hypocenter, the condition of shielding, epilation, and the presence or absence or degree of radiation syndrome. (N.K.)

  6. Ionizing radiation induced cataract

    International Nuclear Information System (INIS)

    Until recently it was believed that the cataract (opacity of the eye lens) is a deterministic effect with a dose threshold of several Gray in dependence on the exposure conditions. Studies in Hiroshima and Nagasaki, in the vicinity of Chernobyl, of American radiologic technologists, astronauts, and patients after having received several computer tomographies of the head region, however, have shown that this assumption is not correct. It had been overlooked in the past that with decreasing dose the latency period is increasing. Therefore, the originally available studies were terminated too early. The more recent studies show that, in the case of a threshold existing at all, it is definitely below 0.8 Gy independently of an acute or a chronic exposure. All studies, however, include 0 Gy in the confidence interval, so that the absence of a dose threshold cannot be excluded. The German Commission on Radiological Protection (Strahlenschutzkommission, SSK) suggested therefore among others: targeted recording of the lens dose during activities which are known to be associated with possible significant lens exposure, examination of the lens should be included as appropriate in the medical monitoring of people occupationally exposed to radiation, if there is potentially high lens exposure, adoption of research strategies to develop a basic understanding of the mechanisms underlying radiation induced cataracts. The International Commission on Radiological Protection (ICRP) actually assumes a threshold dose of 0.5 Gy and, based on this assumption, has recommended in 2011 to reduce the dose limit for the eye lens from 150 mSv in a year to 20 mSv in a year for people occupationally exposed to ionising radiation. (orig.)

  7. Facts about Cataract

    Science.gov (United States)

    ... retinal detachment. Other eye disorders, such as high myopia (nearsightedness), can further increase your risk of retinal ... which have shown varying results in delaying the progression of cataract. Genetic studies, which show promise for ...

  8. Viscoless microincision cataract surgery

    Directory of Open Access Journals (Sweden)

    Guy Sallet

    2008-06-01

    Full Text Available Guy SalletDepartment of Opthamology, Aalsters Stedelijk Ziekenhuis, BelgiumAbstract: A cataract surgery technique is described in which incisions, continuous circular capsulorhexis and hydrodissection are made without the use of any viscoelastics. Two small incisions are created through which the different parts of the procedure can take place, maintaining a stable anterior chamber under continuous irrigation. Subsequent bimanual phacoemulsification can be done through these microincisions. At the end of the procedure, an intraocular lens can be inserted through the self-sealing incision under continuous irrigation. 50 consecutive cataract patients were operated on without the use of viscoelastics and then compared with a group of 50 patients who had been helped with viscoelastics. No difference in outcome, endothelial cell count or pachymetry was noted between the two groups. No intraoperative complication was encountered. Viscoless cataract surgery was a safe procedure with potential advantages.Keywords: ophthalmic visco-surgical device, viscoless cataract surgery, microincision

  9. Cataracts induced by microwave and ionizing radiation

    International Nuclear Information System (INIS)

    Microwaves most commonly cause anterior and/or posterior subcapsular lenticular opacities in experimental animals and, as shown in epidemiologic studies and case reports, in human subjects. The formation of cataracts seems to be related directly to the power of the microwave and the duration of exposure. The mechanism of cataractogenesis includes deformation of heat-labile enzymes, such as glutathione peroxide, that ordinarily protect lens cell proteins and membrane lipids from oxidative damage. Oxidation of protein sulfhydryl groups and the formation of high-molecular-weight aggregates cause local variations in the orderly structure of the lens cells. An alternative mechanism is thermoelastic expansion through which pressure waves in the aqueous humor cause direct physical damage to the lens cells. Cataracts induced by ionizing radiation (e.g., X-rays and gamma rays) usually are observed in the posterior region of the lens, often in the form of a posterior subcapsular cataract. Increasing the dose of ionizing radiation causes increasing opacification of the lens, which appears after a decreasing latency period. Like cataract formation by microwaves, cataractogenesis induced by ionizing radiation is associated with damage to the lens cell membrane. Another possible mechanism is damage to lens cell DNA, with decreases in the production of protective enzymes and in sulfur-sulfur bond formation, and with altered protein concentrations. Until further definitive conclusions about the mechanisms of microwaves and ionizing radiation induced cataracts are reached, and alternative protective measures are found, one can only recommend mechanical shielding from these radiations to minimize the possibility of development of radiation-induced cataracts. 74 references

  10. Cataract surgery in uveitis

    Directory of Open Access Journals (Sweden)

    Hazari Ajit

    2002-01-01

    Full Text Available Purpose:To study the visual outcome of cataract surgery in eyes with uveitis.Methods: A retrospective analysis of patients with uveitis operated for cataract. Results: 106 eyes of 89 patients with uveitis were operated for cataract. In 62.3% eyes (66/106, post -operative follow-up was at least 6 months. There was significant improvement (P<0.001 in visual acuity after cataract surgery. Provided the uveitis was well controlled for three months pre-operatively, additional pre-operative anti-inflammatory medications did not significantly affect (P=0.842 post -operative inflammation. Patients who received extracapsular cataract extraction (ECCE or phacoemulsification with posterior chamber IOL (PCIOL obtained better visual acuity at 6 weeks (P=0.009 and P=0.032 respectively than those with only ECCE without IOL. In 37 eyes vision did not improve due to persistent uveitis (23.9%, 16/67, cystoid macular oedeme (20.9%, 14/67, and posterior capsule opacification (14.9%, 10/67. Conclusion: Cataract extraction and PCIOL implantation is safe in eyes with uveitis. Additional preoperative medications may not alleviate post-operative inflammation if uveitis is well controlled for at least three months before surgery.

  11. Studies on the cause of radiation cataract

    International Nuclear Information System (INIS)

    Since the advent of medical radiations, the radiation injuries have been intensively studied, particularly the eye. Most of the previous investigation has concerned radiation cataractogenesis. There are a variety of opinions regarding the causes of the radiation cataract formation. In this investigation, I consider direct and indirect effects as two mechanisms for radiation induction of cataracts. It is shown that radiation cataracts in albino rabbits should be studied by reference to the alteration of the lens, dynamic study of the aqueous humor and microcirculation of the iris and ciliary body. Experimental evidence from this study supports the hypothesis that cataractogenesis may be caused by the circulatory insufficiency due to radiation damage of the fine vasculature supplying nutrition to the iris and ciliary body. However I can not perfectly deny that cataractogenesis may be caused by the direct radiation injury in this study. (author)

  12. Paediatric cataract implant surgery outcome

    OpenAIRE

    Istiantoro Istiantoro

    2003-01-01

    This study evaluated the surgical outcome of various surgical technique in paediatric cataract implant surgery, at Jakarta Eye Center, Jakarta, Indonesia. This was a retrospective study of 57 eyes in 44 children who had primary cataract implants surgery. Three surgical techniques used were : 1. Extracapsular cataract extraction with intraocular lens implantation with intact posterior capsule which was performed on 21 eyes (group 1). 2. Extracapsular cataract extraction with intraocular lens i...

  13. Neurophysiological mechanisms involved in language learning in adults

    OpenAIRE

    Rodríguez-Fornells, Antoni; Cunillera, Toni; Mestres-Missé, Anna; de Diego-Balaguer, Ruth

    2009-01-01

    Little is known about the brain mechanisms involved in word learning during infancy and in second language acquisition and about the way these new words become stable representations that sustain language processing. In several studies we have adopted the human simulation perspective, studying the effects of brain-lesions and combining different neuroimaging techniques such as event-related potentials and functional magnetic resonance imaging in order to examine the language learning (LL) pro...

  14. Radiation and cataract

    International Nuclear Information System (INIS)

    When this paper was about to go to press, the International Commission on Radiological Protection released a statement recommending a change in the threshold dose for the eye lens and dose limits for eye for occupationally exposed persons. It is clear that the earlier published threshold for radiation cataract is no longer valid. Epidemiological studies among Chernobyl clean-up workers, A bomb survivors, astronauts, residents of contaminated buildings, radiological technicians and recent surveys of staff in interventional rooms indicate that there is an increased incidence of lens opacities at doses below 1 Gy. Nevertheless, eye lens dosimetry is at a primitive stage and needs to be developed further. Despite uncertainties concerning dose threshold and dosimetry, it is possible to significantly reduce the risk of radiation cataract through the use of appropriate eye protection. By increasing awareness among those at risk and better adoption and increased usage of protective measures, radiation cataract can become preventable despite lowering of dose limits. (authors)

  15. Liquefaction for cataract extraction

    Science.gov (United States)

    Labiris, Georgios; Toli, Aspasia; Polychroni, Damaskini; Gkika, Maria; Angelonias, Dimitrios; Kozobolis, Vassilios P.

    2016-01-01

    A systematic review of the recent literature regarding the implementation of the liquefaction in cataract surgery and its short-term and long-term outcomes in various parameters that affect the quality of patients' life, including visual rehabilitation and possible complications was performed based on the PubMed, Medline, Nature and the American Academy of Ophthalmology databases in November 2013 and data from 14 comparative studies were included in this narrative review. Liquefaction is an innovative technology for cataract extraction that uses micropulses of balanced salt solution to liquefy the lens nucleus. Most studies reported that liquefaction is a reliable technology for mild to moderate cataracts, while fragmentation difficulties may be encountered with harder nuclei. PMID:26949656

  16. Cataract extraction with erisophake.

    Science.gov (United States)

    ALEXANDER, H B

    1951-01-01

    Today the erisophake offers the most successful means for the intracapsular extraction of cataracts. The advantages of this method are that no counterpressure is required so that the incidence of vitreous loss is reduced; the vacuum cup provides a firmer grasp of the lens with less danger of rupture of the lens capsule; and the vacuum cup can be used for the delivery of practically all types of cataract in the adult, including intumescent and Morgagnian cataracts as well as lenses with exfoliating and friable capsules. While the forceps method of intracapsular extraction is generally successful in not more than 70 to 75 per cent of cases, the erisophake may offer success in 90 per cent of cases. PMID:14792378

  17. Daily tonometric curves after cataract surgery

    OpenAIRE

    Sacca, S; Marletta, A; Pascotto, A; Barabino, S; Rolando, M.; Giannetti, R.; Calabria, G.

    2001-01-01

    AIM—To evaluate daily tonometric curves after cataract surgery in patients with cataract only and in patients with cataract and glaucoma.
METHODS—108 patients scheduled for cataract surgery were randomly allocated to two groups: 57 patients with cataract only (normal) and 51 with cataract and primary open angle glaucoma (POAG). All patients underwent extracapsular cataract extraction (ECCE) (manual technique with long wound), phacoemulsification (automated technique with short wound), or nucl...

  18. Mechanisms Involved in Exercise-Induced Cardioprotection: A Systematic Review

    Directory of Open Access Journals (Sweden)

    Juliana Pereira Borges

    2015-01-01

    Full Text Available Background: Acute myocardial infarction is the leading cause of morbidity and mortality worldwide. Furthermore, research has shown that exercise, in addition to reducing cardiovascular risk factors, can also protect the heart against injury due to ischemia and reperfusion through a direct effect on the myocardium. However, the specific mechanism involved in exerciseinduced cardiac preconditioning is still under debate. Objective: To perform a systematic review of the studies that have addressed the mechanisms by which aerobic exercise promotes direct cardioprotection against ischemia and reperfusion injury. Methods: A search was conducted using MEDLINE, Literatura Latino-Americana e do Caribe de Informação em Ciências da Saúde, and Scientific Electronic Library Online databases. Data were extracted in a standardized manner by two independent researchers, who were responsible for assessing the methodological quality of the studies. Results: The search retrieved 78 studies; after evaluating the abstracts, 30 studies were excluded. The manuscripts of the remaining 48 studies were completely read and, of these, 20 were excluded. Finally, 28 studies were included in this systematic review. Conclusion: On the basis of the selected studies, the following are potentially involved in the cardioprotective response to exercise: increased heat shock protein production, nitric oxide pathway involvement, increased cardiac antioxidant capacity, improvement in ATP-dependent potassium channel function, and opioid system activation. Despite all the previous investigations, further research is still necessary to obtain more consistent conclusions.

  19. Effect of coffee (caffeine) against human cataract blindness

    Science.gov (United States)

    Varma, Shambhu D

    2016-01-01

    Previous biochemical and morphological studies with animal experiments have demonstrated that caffeine given topically or orally to certain experimental animal models has significant inhibitory effect on cataract formation. The present studies were undertaken to examine if there is a correlation between coffee drinking and incidence of cataract blindness in human beings. That has been found to be the case. Incidence of cataract blindness was found to be significantly lower in groups consuming higher amounts of coffee in comparison to the groups with lower coffee intake. Mechanistically, the caffeine effect could be multifactorial, involving its antioxidant as well as its bioenergetic effects on the lens. PMID:26869755

  20. Cataract surgery and anticoagulants

    NARCIS (Netherlands)

    Koopmans, SA; VanRij, G

    1996-01-01

    A questionnaire was sent to 240 members of the Netherlands Intraocular implant Club (NIOIC) to register their policy followed in 1993 with regard to anticoagulant therapy (ACT) and the use of aspirin in patients having cataract surgery. Ninety-one (32%) forms were suitable for analysis. Most eye sur

  1. Neurophysiological mechanisms involved in language learning in adults.

    Science.gov (United States)

    Rodríguez-Fornells, Antoni; Cunillera, Toni; Mestres-Missé, Anna; de Diego-Balaguer, Ruth

    2009-12-27

    Little is known about the brain mechanisms involved in word learning during infancy and in second language acquisition and about the way these new words become stable representations that sustain language processing. In several studies we have adopted the human simulation perspective, studying the effects of brain-lesions and combining different neuroimaging techniques such as event-related potentials and functional magnetic resonance imaging in order to examine the language learning (LL) process. In the present article, we review this evidence focusing on how different brain signatures relate to (i) the extraction of words from speech, (ii) the discovery of their embedded grammatical structure, and (iii) how meaning derived from verbal contexts can inform us about the cognitive mechanisms underlying the learning process. We compile these findings and frame them into an integrative neurophysiological model that tries to delineate the major neural networks that might be involved in the initial stages of LL. Finally, we propose that LL simulations can help us to understand natural language processing and how the recovery from language disorders in infants and adults can be accomplished. PMID:19933142

  2. Manual small incision cataract surgery in eyes with white cataracts

    OpenAIRE

    Venkatesh Rengaraj; Das Manoranjan; Prashanth Sadasivam; Muralikrishnan Radhakrishnan

    2005-01-01

    PURPOSE: To assess the safety and efficacy of Manual Small Incision Cataract Surgery (MSICS) in cases of white cataract with the use of trypan blue as an adjunct for performing continuous curvilinear capsulorthexis (CCC). MATERIALS AND METHODS: Prospective observational study on 100 consecutive eyes of 100 patients with white cataract who had undergone MSICS with trypan blue assisted CCC. The nucleus was prolapsed into anterior chamber by using a sinskey hook and extracted out of the eye u...

  3. Three cases of extracapsular cataract extraction for radiation cataract

    Energy Technology Data Exchange (ETDEWEB)

    Hirokane, Kenji; Kosaka, Toshiya; Nii, Hiroki; Kiuchi, Yoshiaki; Nakano, Kensuke; Choshi, Kanji [Hiroshima Univ. (Japan). School of Medicine

    1996-02-01

    Extracapsular cataract extraction and intraocular lens implantation was performed on 4 eyes of 3 patients with radiation cataract. Case 1 was a 60-year-old man who was exposed to the ionizing radiation of the atomic bomb in Hiroshima 730 meters from the center of the explosion. He developed atomic bomb radiation senile cataracts in both eyes. Despite cataract surgery, a central plaque remained on the posterior capsule in the region corresponding to the central dense opacity in both eyes. Case 2 was an 81-year-old man who was in a streetcar 1,000 meters from the center of the explosion at the time of the atomic bombing. Senile and radiation-induced cataract decreased the visual acuity in both eyes. After extracapsular cataract extraction in his right eye, central opacification and a fibrous white membrane remained on the posterior capsule. These were removed by Nd-YAG laser capsulotomy six days after surgery. Case 3 was a 56-year-old man who developed radiation cataract after radiation therapy to a malignant lymphoma in the right orbit. Phacoemulsification and aspiration could not remove the fibrous white membrane from the posterior capsule in this case. Central opacities and fibrous white membranes on the posterior capsule after cataract surgery appears to be a characteristic of radiation cataract. (author).

  4. Three cases of extracapsular cataract extraction for radiation cataract

    International Nuclear Information System (INIS)

    Extracapsular cataract extraction and intraocular lens implantation was performed on 4 eyes of 3 patients with radiation cataract. Case 1 was a 60-year-old man who was exposed to the ionizing radiation of the atomic bomb in Hiroshima 730 meters from the center of the explosion. He developed atomic bomb radiation senile cataracts in both eyes. Despite cataract surgery, a central plaque remained on the posterior capsule in the region corresponding to the central dense opacity in both eyes. Case 2 was an 81-year-old man who was in a streetcar 1,000 meters from the center of the explosion at the time of the atomic bombing. Senile and radiation-induced cataract decreased the visual acuity in both eyes. After extracapsular cataract extraction in his right eye, central opacification and a fibrous white membrane remained on the posterior capsule. These were removed by Nd-YAG laser capsulotomy six days after surgery. Case 3 was a 56-year-old man who developed radiation cataract after radiation therapy to a malignant lymphoma in the right orbit. Phacoemulsification and aspiration could not remove the fibrous white membrane from the posterior capsule in this case. Central opacities and fibrous white membranes on the posterior capsule after cataract surgery appears to be a characteristic of radiation cataract. (author)

  5. Quantum-Mechanical Calculations on Molecular Substructures Involved in Nanosystems

    Directory of Open Access Journals (Sweden)

    Beata Szefler

    2014-09-01

    Full Text Available In this review article, four ideas are discussed: (a aromaticity of fullerenes patched with flowers of 6-and 8-membered rings, optimized at the HF and DFT levels of theory, in terms of HOMA and NICS criteria; (b polybenzene networks, from construction to energetic and vibrational spectra computations; (c quantum-mechanical calculations on the repeat units of various P-type crystal networks and (d construction and stability evaluation, at DFTB level of theory, of some exotic allotropes of diamond D5, involved in hyper-graphenes. The overall conclusion was that several of the yet hypothetical molecular nanostructures herein described are serious candidates to the status of real molecules.

  6. Phacoemulsification in subluxated cataract.

    Directory of Open Access Journals (Sweden)

    Praveen M

    2003-01-01

    Full Text Available Purpose: To evaluate the outcome of phacoemulsification in eyes with subluxated cataract. Materials and Methods: This retrospective study comprised 22 eyes of 20 consecutive patients with subluxated cataracts of varying aetiology operated between March 1998 and March 2001. Detailed preoperative assessment included visual acuity (VA, slitlamp examination, presence of vitreous in anterior chamber, extent of subluxation, intraocular pressure (IOP and detailed fundus examination. Phacoemulsification was done to retain the natural bag support and all patients had acrylic foldable Acrysof IOL implantation either in-the-bag or by scleral fixation. Postoperative observations included best-corrected visual acuity (BCVA, IOP, pupillary reaction and the IOL position. Results: The aetiology of the subluxation was traumatic in 11 patients and non-traumatic in 9 patients. Fifteen were males and 5 were females. Mean follow-up was 11.7 ± 9.71 months (range 4-39. The average age was 39.15 ± 16.33 (range 5 - 74. A 2-port anterior chamber vitrectomy was performed in 6 eyes (27.2%. Capsule tension ring (CTR was implanted in 15 eyes (68.18%. Twelve eyes (54.5% had in-the-bag implants, while 5 (22.72% had scleral fixation. The remaining 5 eyes (22.72% had one haptic in-the-bag and another sutured to sclera. No major intraoperative complications were noted. Twelve eyes (54.5% had clinically and geometrically well centered IOLs while 9 eyes (40.9% had geometrically decentered IOLs. One patient was lost to follow-up. Fifteen eyes (55.55% had postoperative BCVA of 6/12 - 6/6 while 2 eyes (7.40% had BCVA of 6/18. The remaining 4 eyes (14.81% had less than 6/24 BCVA due to pre-existing posterior segment pathology. Postoperative complications included rise in IOP in 1 eye (4.54%, pupillary capture of the IOL optic in 2 eyes (9.09%; the same 2 eyes (9.09% required redialing of IOL. One eye (4.54% had to undergo refixation (one haptic was fixed to sclera year after cataract

  7. Oxidative stress as a predictor of cataract surgery outcomes

    OpenAIRE

    M. A. Kovalevskaya; N. V. Vedrintseva

    2015-01-01

    Exhaustion of anti-oxidative potential and oxidative stress are considered as trigger mechanisms of cataract development. Products of free radical oxidation are accumulated in lens. Decrease in water solubility of proteins results in the sorption of uncharged proteins on cellular membranes. This affects regular lenticular membrane folding. Light scattering on folded membranes of lenticular fibers is considered as a primary cause of lens opacities in cataract. Most problems occur in complicate...

  8. Cataract extraction and lens implantation with and without trabeculectomy: an intrapatient comparison.

    OpenAIRE

    Bobrow, J C

    1998-01-01

    OBJECTIVE: To determine whether cataract extraction and lens implantation combined with trabeculectomy provides better long-term results than cataract extraction and lens implantation alone in a group of patients with primary open-angle glaucoma and cataract randomly selected to receive surgery with trabeculectomy in one eye and without in the other. METHODS: A prospective, randomized clinical trial involving 35 patients with bilateral symmetric primary open-angle glaucoma and visually disabl...

  9. Mechanisms involved in vibratory destabilization of NAPL ganglia in sands

    International Nuclear Information System (INIS)

    Immiscible liquids when spilled into the ground or leaked from underground storage tanks tend to remain trapped in the form of discrete ganglia due to strong capillary forces. These ganglia often have low solubility in water and may remain in the subsurface over long periods of time creating a continuous source of pollution. Previous studies, which were exploratory in nature, showed that creation of localized vibrations could recover high percentages of trapped ganglia. In this paper, the mechanisms involved in the vibratory destabilization of ganglia are analyzed using results from two sets of experimental studies. It is postulated that, when vibrations result in compaction of sands, viscous pressures tend to destabilize the ganglia by splitting them whereas buoyancy pressures increase the maximum sustainable lengths. The roles of viscous and buoyancy pressures are reversed when vibrations result in increased porosities due to expansion (dilation) of soil. The volumes of trapped ganglia recovered during the experiments are consistent with these postulates. Experimental results also indicate significant recoveries in the cases where the ganglia are supposed to remain stable. These recoveries are attributed to the transient particle rearrangement during vibrations, which is concluded to be an important mechanism

  10. Cellular and Humoral Mechanisms Involved in the Control of Tuberculosis

    Directory of Open Access Journals (Sweden)

    Joaquin Zuñiga

    2012-01-01

    Full Text Available Mycobacterium tuberculosis (Mtb infection is a major international public health problem. One-third of the world's population is thought to have latent tuberculosis, a condition where individuals are infected by the intracellular bacteria without active disease but are at risk for reactivation, if their immune system fails. Here, we discuss the role of nonspecific inflammatory responses mediated by cytokines and chemokines induced by interaction of innate receptors expressed in macrophages and dendritic cells (DCs. We also review current information regarding the importance of several cytokines including IL-17/IL-23 in the development of protective cellular and antibody-mediated protective responses against Mtb and their influence in containment of the infection. Finally, in this paper, emphasis is placed on the mechanisms of failure of Mtb control, including the immune dysregulation induced by the treatment with biological drugs in different autoimmune diseases. Further functional studies, focused on the mechanisms involved in the early host-Mtb interactions and the interplay between host innate and acquired immunity against Mtb, may be helpful to improve the understanding of protective responses in the lung and in the development of novel therapeutic and prophylactic tools in TB.

  11. Changing indications for cataract surgery.

    OpenAIRE

    Cairns, L.; Sommer, A

    1984-01-01

    Despite the fact that two community-based surgeons switched from routine intracapsular cataract extraction to planned extracapsular cataract surgery and routine implantation of posterior chamber lenses, they did not materially increase the size of their surgical load or change their indications for cataract surgery. In contrast a similar change in surgical technique by two high-referral hospital-based surgeons was associated with a marked increase in operative rates and increased preoperative...

  12. Etiopathogenesis of cataract: An appraisal

    OpenAIRE

    Gupta, Varun B; Manjusha Rajagopala; Basavaiah Ravishankar

    2014-01-01

    Natural eye lens is a crystalline substance to produce a clear passage for light. Cataract is opacity within the clear lens of the eye and is the dominant cause of socio-medical problem i.e., blindness worldwide. The only available treatment of cataract is surgery. However, insufficient surgical facilities in poor and developing countries and post-operative complications inspire researchers to find out other modes of treatment for cataract. In this review, an attempt has been made to appraise...

  13. Cataracts in uranium miners

    International Nuclear Information System (INIS)

    The question was studied of whether or not uranium miners with a long history of work underground develop alterations of the eye lens as a result of a long-term chronic exposure to gamma radiation. Investigated were the area of opacities and the occurrence of alterations of the lens posterior pole in a group of 800 uranium miners (i.e., 1,600 eyes) with work underground longer than 10 years. As against controls, no statistical differences were found in the lens transparency. Significant differences were also not found in the extent of cataracts and the occurrence of posterior pole alterations, nor in the rate of an increased occurrence of cataracts due to age. (L.O.)

  14. Pseudoexfoliation syndrome and secondary cataract

    OpenAIRE

    Kuchle, M.; A. Amberg; Martus, P.; Nguyen, N.; NAUMANN, G.

    1997-01-01

    AIM/BACKGROUND—The pseudoexfoliation (PEX) syndrome is frequently associated with impairment of the blood-aqueous barrier. This study analysed if this might stimulate secondary cataract following cataract extraction.
METHODS—This historical cohort study included 197 eyes of 197 patients (99 with and 98 without PEX) that underwent extracapsular cataract extraction with posterior chamber lens implantation (PMMA optic) between 1985 and 1991. Secondary cataract was defined as opacification of the...

  15. Femtosecond laser cataract surgery

    OpenAIRE

    Nagy, Zoltan Z.; McAlinden, Colm

    2015-01-01

    Femtosecond laser (FSL) cataract surgery is in its infancy but is rapidly gaining popularity due to the improved consistency and predictability for corneal incisions and anterior capsulorhexis. It enables subsequently less phacoemulsification energy and time to be employed, which has gains in terms of reduced corneal oedema. In addition, the FSL allows better circularity of the anterior capsulotomy, capsule overlap, intraocular lens (IOL) placement and centration of the IOL. These advantages ...

  16. Astigmatism following cataract surgery.

    OpenAIRE

    Reading, V M

    1984-01-01

    The changes in corneal curvature were determined at regular intervals over a one-year period following intracapsular cataract extraction by microsurgical techniques. During the first postoperative month photokeratometric measurements showed rapid changes in astigmatism associated with large changes in the direction of the axis. Thereafter astigmatism against-the-rule predominated. Data from the small group of patients who underwent surgery in which the technique of phacoemulsification was use...

  17. Keratoplasty and cataract extraction

    OpenAIRE

    Panda Anita; Kumar T

    1991-01-01

    Fifty eyes were evaluated following penetrating keratoplasty and cataract extraction. Twenty five of them had intracapsular lens extraction while the remaining 25 had intercapsular method of extracapsular lens extraction. Both operative and post operative complications were more in group I. Visual outcome and graft clarity were also better in eyes of group II. Combined keratoplasty and intercapsular method of extracapsular lens extraction was recommended in eyes having both corneal and lentic...

  18. Keratoplasty and cataract extraction

    Directory of Open Access Journals (Sweden)

    Panda Anita

    1991-01-01

    Full Text Available Fifty eyes were evaluated following penetrating keratoplasty and cataract extraction. Twenty five of them had intracapsular lens extraction while the remaining 25 had intercapsular method of extracapsular lens extraction. Both operative and post operative complications were more in group I. Visual outcome and graft clarity were also better in eyes of group II. Combined keratoplasty and intercapsular method of extracapsular lens extraction was recommended in eyes having both corneal and lenticular pathology.

  19. Cataract and ionizing radiation

    International Nuclear Information System (INIS)

    The radiation-induced cataract has been up to now considered as a quite rare pathology, needing high-dose radiations (beyond a dose threshold roughly estimated at 2 Grays to the lens) consisting mainly in head tumour radiotherapy complications. Several new studies on different exposed populations such as astronauts, japanese atomic bomb survivors, people undergoing X-ray examinations, Chernobyl accident 'liquidators' as well as data from animal experiments, suggest that dose threshold for detectable opacities as well as for clinical posterior sub-capsular cataract occurring, might be far lower than those previously assumed. Even the existence of a dose threshold is no longer an absolute certitude insofar as radiation-induced cataract pathogenesis might consist not really in a deterministic effect (direct tissue harmful effect, killing or seriously injuring a critical population of cells) as believed until now, but rather in a stochastic effect (genomic damage in target-cells, altered cell division, abnormal lens fiber cell differentiation). More practically, these new data may lead us to reconsider radioprotection of specifically exposed populations: mainly patients and workers. Regarding workers, labour legislation (lens equivalent dose limit of 150 mSv during 12 consecutive months) might be, in the medium term, reassessed downwards. (author)

  20. Radiation-induced cataract

    International Nuclear Information System (INIS)

    Dose assessments for cataract threshold doses are available based on epidemiological studies of radiotherapy patients, survivors of the nuclear bombing of Hiroshima and Nagasaki, and of persons with occupational exposure to radiation. According to these, short-term application of low-level LET radiation of a dose ranging between 0.5 and 2.0 Gy may suffice to cause a cataract in the course of a few months or years which results in inpairment of vision (UNSCEAR, 1982). In fractionated irradiation, cataractogenic threshold dose increases to 4 Sv at treatment times between 3 weeks and 3 months, and to more than 5 Sv at more than 3 months (ICRP 41). Densely ionizing radiation must be assumed to have threshold doses between 2 and 20 Sv. An ICRP assessment (ICRP Publ. No. 41, 1984) gives a threshold dose of more than 8 Sv for a vision-impairing cataract if these was protracted irradiation at a low-level dose rate. Concerning radiation protection, a maximum lens dose of 150 mSv per annum was recommended which should not be exceeded. This indicates a maximum of 7.5 Sv of exposure throughout a period of 50 years of working life. (orig./HP)

  1. Molecular mechanisms involved in chemoresistance in paediatric acute lymphoblastic leukaemia

    Directory of Open Access Journals (Sweden)

    Stanković Tatjana

    2008-01-01

    Full Text Available Acute lymphoblastic leukaemia (ALL is the most common paediatric cancer. Despite cure rates approaching 80%, resistance to treatment and disease relapse remain a significant clinical problem. Identification of the genes and biological pathways responsible for chemoresistance is therefore crucial for the design of novel therapeutic approaches aiming to improve patient survival. Mutations in the membrane transporter P-glycoprotein genes, genetic variations in drug-metabolising enzymes and defects in apoptotic pathways are mechanisms of chemoresistance common to a wide spectrum of cancers and also play a role in paediatric ALL. In addition, several recent microarray studies have identified transcriptional profiles specifically associated with chemoresistance and pointed to a number of potentially novel therapeutic targets. These microarray studies have shown that genes discriminating between clinically responsive and resistant leukaemias tend to be involved in cellular processes such as regulation of cell cycle, proliferation, and DNA repair. Here we review the outcomes of these microarray studies and also present our own investigations into apoptotic resistance to DNA double strand breaks (DSBs in paediatric ALL. We present stratification of paediatric ALL by the profile of DNA damage response following ionising radiation (IR in vitro. This approach allows classification of ALL tumours at presentation into IR-apoptotic sensitive and IR-apoptotic resistant. Furthermore, apoptotic resistant leukaemias exhibit abnormal response of NFkB pathway following irradiation and inhibition of this pathway can sensitise leukaemic cells to IR-induced DSBs.

  2. SMALL INCISION CATARACT SURGERY VERSUS PHACOEMULSIFICATION FOR IMMATURE CATARACT: A SINGLE BLIND RANDOMIZED CONTROLLED TRIAL

    OpenAIRE

    Md. Jawed; Himadri; De, Abhijit; Rathindra; Deshmukh Md Saudmiya

    2014-01-01

    BACKGROUND: Manual small incision cataract surgery (SICS) has given visual results almost equivalent to Phacoemulsification but limited studies are available regarding the efficacy of small incision cataract surgery in phaco suitable immature cataracts. OBJECTIVE: To compare manual small incision cataract surgery and Phacoemulsification in immature cataracts. MATERIALS AND METHODS: A single blind randomized controlled trial was conducted with 105 eyes each for small incisi...

  3. Simultaneous pterygium and cataract surgery.

    Directory of Open Access Journals (Sweden)

    Gulani A

    1995-01-01

    Full Text Available In our country both pterygium and cataract have a high incidence. Hence in this study, thirty patients with pterygium and cataract were treated with a simultaneous pterygium excision and cataract extraction procedure. These patients after pterygium excision were treated intra-operatively with 500 rads of beta radiation over the pterygium site. Then, the cataract was extracted and the patients were treated post-operatively with topical betamethasone 0.1% for a duration of three months. They were followed up for a duration of 6 months postoperatively. Nineteen patients (63% had visual recovery to 6/12. Twelve of 30 patients (40% had recurrence of pterygium. The combined procedure did not result in any surgical complications following cataract removal. Post-operatively, after 6 months 13 patients had with the rule astigmatism (WRA for a mean WRA of 1.3 D, and 17 had against the rule astigmatism (ARA for a mean ARA of 1.2 D.

  4. Diplopia as the Complication of Cataract Surgery.

    Science.gov (United States)

    Gawęcki, Maciej; Grzybowski, Andrzej

    2016-01-01

    The authors present systematic review of aetiology and treatment of diplopia related to cataract surgery. The problem is set in the modern perspective of changing cataract surgery. Actual incidence is discussed as well as various modalities of therapeutic options. The authors provide the guidance for the contemporary cataract surgeon, when to expect potential problem in ocular motility after cataract surgery. PMID:26998351

  5. Diplopia as the Complication of Cataract Surgery

    OpenAIRE

    Maciej Gawęcki; Andrzej Grzybowski

    2016-01-01

    The authors present systematic review of aetiology and treatment of diplopia related to cataract surgery. The problem is set in the modern perspective of changing cataract surgery. Actual incidence is discussed as well as various modalities of therapeutic options. The authors provide the guidance for the contemporary cataract surgeon, when to expect potential problem in ocular motility after cataract surgery.

  6. Outcome after surgery of congenital cataract

    OpenAIRE

    Lundvall, Anna

    2002-01-01

    The visual outcome in infants undergoing surgery for bilateral congenital cataract has improved considerably because of improved surgical methods and the realisation that early detection, allowing early cataract extraction and immediate optical correction, can prevent otherwise irreversible deprivation amblyopia. The management of unilateral congenital cataract is still of the most difficult problems in paediatric ophtalmology. In unilateral congenital cataract, interven...

  7. Femtosecond laser cataract surgery.

    Science.gov (United States)

    Nagy, Zoltan Z; McAlinden, Colm

    2015-01-01

    Femtosecond laser (FSL) cataract surgery is in its infancy but is rapidly gaining popularity due to the improved consistency and predictability for corneal incisions and anterior capsulorhexis. It enables subsequently less phacoemulsification energy and time to be employed, which has gains in terms of reduced corneal oedema. In addition, the FSL allows better circularity of the anterior capsulotomy, capsule overlap, intraocular lens (IOL) placement and centration of the IOL. These advantages have resulted in improved visual and refractive outcomes in the short term. Complication rates are low which reduce with surgeon experience. This review article focuses on the Alcon LenSx system. PMID:26605364

  8. Etiopathogenesis of cataract: An appraisal

    Directory of Open Access Journals (Sweden)

    Varun B Gupta

    2014-01-01

    Full Text Available Natural eye lens is a crystalline substance to produce a clear passage for light. Cataract is opacity within the clear lens of the eye and is the dominant cause of socio-medical problem i.e., blindness worldwide. The only available treatment of cataract is surgery. However, insufficient surgical facilities in poor and developing countries and post-operative complications inspire researchers to find out other modes of treatment for cataract. In this review, an attempt has been made to appraise various etiological factors of cataract to make their perception clear to build up counterpart treatment. Present study is an assortment of various available literatures and electronic information in view of cataract etiopathogenesis. Various risk factors have been identified in development of cataracts. They can be classified in to genetic factors, ageing (systemic diseases, nutritional and trace metals deficiencies, smoking, oxidative stress etc., traumatic, complicated (inflammatory and degenerative diseases of eye, metabolic (diabetes, galactosemia etc., toxic substances including drugs abuses, alcohol etc., radiation (ultraviolet, electromagnetic waves etc. are implicated as significant risk factors in the development of cataract.

  9. Recovery after cataract surgery.

    Science.gov (United States)

    Porela-Tiihonen, Susanna; Kokki, Hannu; Kaarniranta, Kai; Kokki, Merja

    2016-04-01

    Cataract surgery is the most common ophthalmological surgical procedure, and it is predicted that the number of surgeries will increase significantly in the future. However, little is known about the recovery after surgery. The first aim of this study was to evaluate the prevalence, severity and duration of pain and other ocular discomfort symptoms experienced after cataract surgery. The other objectives were to identify the factors associated with lower postoperative patient satisfaction and to measure the effect of cataract surgery on patients' health-related quality of life (HRQoL) and visual function in everyday life. The study design was a prospective follow-up study. The course of the recovery and the presence of ocular symptoms were evaluated by interviewing the patients via a questionnaire at 1 day, 1 week, 6 weeks and one year after surgery The visual functioning in everyday life was measured with Visual Functioning Index VF-7 and Catquest-9SF-questionnaires and furthermore the HRQoL was measured with the 15D-instrument before surgery and at 12 months after surgery. The patients returned the questionnaires by mail and were interviewed in the hospital on the day of the surgery. The same patients filled-in all the questionnaires. The patient reports were used to collect the data on medical history. A total of 303 patients were approached at Kuopio University Hospital in 2010-2011 and of these 196 patients were eligible and willing to participate, with postoperative data being available from 186 (95%) patients. A systematic review article was included in the study procedure and it revealed the wide range in the reported incidence of postoperative ocular pain. Some of the identified randomized controlled studies reported no or only minor pain whereas in some studies significant pain or pain lasting for several weeks has been described in more than 50% of the study patients. In the present study setting, pain was reported by 34% during the first

  10. Ochratoxin A carcinogenicity involves a complex network of epigenetic mechanisms.

    Science.gov (United States)

    Marin-Kuan, Maricel; Cavin, Christophe; Delatour, Thierry; Schilter, Benoît

    2008-08-01

    Ochratoxin A (OTA) is a mycotoxin occurring in a wide range of food products. Because of the limitation of human epidemiological data, the safety significance of OTA in food has to rely on animal data, with renal toxicity and carcinogenicity being considered the pivotal effects. The elucidation of the mechanism of action would improve the use of experimental animal data for risk assessment. Direct genotoxicity versus epigenetic mechanisms appears to be a key question. In the present review, the increasingly documented epigenetic cellular effects of OTA and their potential toxicological relevance are discussed. The information available suggests that OTA is unlikely to act through a single, well-defined mechanism of action. Instead, it is proposed that a network of interacting epigenetic mechanisms, including protein synthesis inhibition, oxidative stress and the activation of specific cell signalling pathways, is responsible for OTA carcinogenicity. From a risk assessment perspective, it has to be noted that the mechanisms proposed above depend mainly upon gene expression and enzyme activation, and are, therefore, likely to be thresholded. PMID:18649906

  11. The Pediatric Cataract Register (PECARE)

    DEFF Research Database (Denmark)

    Haargaard, Birgitte; Nyström, Alf; Rosensvärd, Annika; Tornqvist, Kristina; Magnusson, Gunilla

    2015-01-01

    between January 2008 and December 2012 were included. Statistical comparison of the different screening strategies was made. RESULTS: The number of children undergoing surgery for congenital cataract before 1 year of age was 31 (17 bilateral cases) in Denmark and 92 (38 bilateral cases) in Sweden. The......PURPOSE: To analyse and discuss screening for the detection of congenital cataract in two Nordic countries, Denmark and Sweden. METHODS: Until 2011, in Denmark, no guideline concerning screening for congenital cataract existed. Since 2011, Danish guidelines regarding eye examination include...... examination with a pencil light at age 5 weeks, whereas newborn red reflex examination using a handheld ophthalmoscope is routine protocol in Swedish maternity wards. Data regarding age of referral were derived from the Pediatric Cataract Register (PECARE). All children operated on before 1 year of age...

  12. Complications of cataract surgery.

    Science.gov (United States)

    Chan, Elsie; Mahroo, Omar A R; Spalton, David J

    2010-11-01

    Modern cataract surgery is safe in more than 95 per cent of patients. In the small number of cases where a serious complication occurs, the most common is an intra-operative posterior capsular rupture. This can lead to vitreous loss or a dropped nucleus and can increase the risk of post-operative cystoid macular oedema or retinal detachment. Post-operatively, posterior capsular opacification is the most common complication and can be readily treated with a YAG capsulotomy. The most devastating complication is endophthalmitis, the rate of which is now significantly decreased through the use of intracameral antibiotics. As a clinician, the most important step is to assess the patient pre-operatively to predict higher risk individuals and to counsel them appropriately. In these patients, various pre- or intra-operative management steps can be taken in addition to routine phacoemulsification to optimise their visual outcome. PMID:20735786

  13. Congenital cataract screening

    Directory of Open Access Journals (Sweden)

    Zhale Rajavi

    2016-01-01

    Full Text Available Congenital cataract is a leading cause of visual deprivation which can damage the developing visual system of a child; therefore early diagnosis, management and long-term follow-up are essential. It is recommended that all neonates be screened by red reflex examination at birth and suspected cases be referred to ophthalmic centers. Early surgery (1 year is highly recommended. After surgery, amblyopia treatment and periodic follow-up examinations should be started as soon as possible to achieve a satisfactory visual outcome. Practitioners should consider the possibility of posterior capsular opacity, elevated intraocular pressure and amblyopia during follow-up, especially in eyes with microphthalmia and/or associated congenital anomalies. All strabismic children should undergo slit lamp examination prior to strabismus surgery to rule out congenital lens opacities. From a social point of view, equal and fair medical care should be provided to all children regardless of gender.

  14. Cataract formation following vitreoretinal procedures

    OpenAIRE

    Feng H; Adelman RA

    2014-01-01

    Hao Feng, Ron A Adelman Department of Ophthalmology and Visual Science, Yale University School of Medicine, New Haven, CT, USA Purpose: To evaluate the incidence and prevalence of cataract formation, progression, and extraction in patients that underwent vitreoretinal procedures and to evaluate factors that can potentially predispose patients to postoperative cataracts.Materials and methods: The medical records of consecutive patients who underwent vitreoretinal surgery at the Yale Eye Cent...

  15. Neuroleptanalgesia and extracapsular cataract extraction.

    OpenAIRE

    Hodgkins, P R; Teye-Botchway, L; Morrell, A. J.; Fetherston, T J; Perthen, C; Brown, N E

    1992-01-01

    Peribulbar and retrobulbar anaesthesia are commonly used techniques in cataract extraction. They offer satisfactory analgesia and akinesia but serious complications although uncommon are consistently reported. Intravenous sedation combined with a facial nerve block offers an alternative method of anaesthesia. This is a retrospective study of patients who underwent extracapsular cataract extraction using this technique between 1 January 1986 and 1 September 1990. The operating conditions were ...

  16. Sequelae of neglected senile cataract

    OpenAIRE

    2013-01-01

    Cataract is the most common cause of blindness in the world. An attack of phacolytic and phacomorphic glaucoma as a result of neglected cataract constitutes a medical emergency that must be addressed immediately. Ocular emergencies such as these is challenging for the surgeon with guarded or poor prognosis. We describe the presentation, management and prognosis of three cases of phacomorphic and phacolytic glaucoma. All three patients underwent aggressive management of intraocular pressure. D...

  17. VISUAL OUTCOME AFTER CATARACT SURGERY IN COMPLICATED CATARACT

    Directory of Open Access Journals (Sweden)

    Satish

    2014-08-01

    Full Text Available AIMS: To study various factors responsible for visual outcome after cataract surgery in complicated cataract secondary to uveitis. SETTINGS AND STUDY DESIGN: A Retrospective, Clinical study was carried out at tertiary eye care center in central Maharashtra from Jan. 2002 to Jan. 2007 which included 60 eyes of 52 patients. METHODS AND MATERIAL: It was a retrospective study of patients with uveitis undergone cataract surgery between Jan. 2002 to Jan. 2007, at Shri Ganapati Netralaya, Jalna. It included patients of all age groups, both genders, diagnosed of complicated cataract due to uveits subjected to cataract surgery with IOL implantation and detailed preoperative and postoperative -UCVA, BCVA, SLE, and Fundus evaluation with at least 3 months follow up. Follow up was on 1'st post-operative day, 1 week post-operative, 1 month post-operative and 3 months post-operative. We excluded patients with complicated cataract other than uveitic origin, post-operative follow up less than 3 months and patients with ocular diseases other than uveitis. TESTS APPLIED: Paired & Unpaired t-test. RESULTS: 1 Visual acuity: BCVA (>6/12 in 43(71.67 % eyes. 2 TYPE OF SURGERY: ECCE+IOL,(3 SICS+IOL,(5 SICS+AV(1 PE+IOL.(51 3 Type of IOL used: PMMA,(46 HSM,(2 Acrylic.(11 4 Postoperative complications:- CME-1(1.66%, Recurrence of Uveitis-9(15%, PCO:-19(31.66%, Posterior synaechie: 3 (5%, Hyphema:-2 (3.33%, Hypotony:-4 (6.66%, Secondary Glaucoma:-2 (3.33% RD:-1 (1.66%. CONCLUSIONS: 1 Visual outcome after cataract surgery in complicated cataract is statistically significant (P<0.0001 in our study. 2 The best technique of surgery remains Phacoemulsification with in-the-bag IOL implantation of PCIOL. 3 Use of pupil dilating technique's (Iris hook, Sphincterotomy is helpful in making adequate size capsulorrhexis and thereby reducing post-operative complications like anterior capsular opacification & capsular phimosis. 4 The most important predictor of successful cataract

  18. Cataract surgery in pseudoexfoliation syndrome.

    Science.gov (United States)

    Sangal, Neha; Chen, Teresa C

    2014-01-01

    Pseudoexfoliation (PXF) syndrome is characterized by the deposition of distinctive fibrillar material in the anterior segment of the eye. It is an age-related process that is associated with open and narrow angle glaucomas and the formation of cataracts. Not only is PXF associated with the formation of dense nuclear cataracts, it is also well known that those presenting with PXF are at a higher risk of developing complications during, and even after, cataract surgery. Complications associated with cataract surgery in PXF can occur from poor pupillary dilation, zonular weakness leading to intraoperative or postoperative lens dislocation and vitreous loss, postoperative intraocular pressure (IOP) spikes potentiating glaucomatous damage, capsular phimosis, prolonged inflammation, and postoperative corneal decompensation. The surgeon should be prepared to encounter the various potential intraoperative and postoperative complications in eyes with pseudoexfoliation syndrome during cataract surgery. In this way, the surgeon can plan his/her surgical technique to help avoid surprises during cataract surgery and be prepared to manage the potential postoperative complications that can occur in pseudoexfoliation eyes. PMID:25325866

  19. Orosensory self-stimulation by sucrose involves brain dopaminergic mechanisms.

    Science.gov (United States)

    Schneider, L H

    1989-01-01

    The most convincing body of evidence supporting a role for brain dopaminergic mechanisms in sweet taste reward has been obtained using the sham-feeding rat. In rats prepared with a chronic gastric fistula and tested with the cannula open, intake is a direct function of the palatability of the solution offered as well as of the state of food deprivation. Because essentially none of the ingested fluid passes on to the intestine, negative postingestive feedback is eliminated. Thus, the relative orosensory/hedonic potency of the food determines and sustains the rate of sham intake; long periods of food deprivation are not required. In this way, the sham feeding of sweet solutions may be considered a form of oral self-stimulation behavior and afford a preparation through which the neurochemical and neuranatomical substrates of sweet taste reward may be identified. The results obtained in the series of experiments summarized in this paper clearly indicate that central D-1 and D-2 receptor mechanisms are critical for the orosensory self-stimulation by sucrose in the rat. In conclusion, I suggest that such investigations of the roles of brain dopaminergic mechanisms in the sucrose sham-feeding rat preparation may further our understanding of normal and aberrant attractions to sweet fluids in humans (see Cabanac, Drewnowski, and Halmi, this volume), as an innate, positive affective response of human neonates to sucrose and the sustained positive hedonic ratings for glucose when tasted but not when consumed have demonstrated. PMID:2699194

  20. Manual small incision cataract surgery in eyes with white cataracts

    Directory of Open Access Journals (Sweden)

    Venkatesh Rengaraj

    2005-01-01

    Full Text Available PURPOSE: To assess the safety and efficacy of Manual Small Incision Cataract Surgery (MSICS in cases of white cataract with the use of trypan blue as an adjunct for performing continuous curvilinear capsulorthexis (CCC. MATERIALS AND METHODS: Prospective observational study on 100 consecutive eyes of 100 patients with white cataract who had undergone MSICS with trypan blue assisted CCC. The nucleus was prolapsed into anterior chamber by using a sinskey hook and extracted out of the eye using irrigating vectis. Intraoperative and postoperative findings (according to OCTET classification as well as postoperative visual outcomes were used as main measures to report the safety and efficacy of the surgery. RESULTS: Of the 100 eyes, 16 had intumescent, 67 had mature and 17 had hypermature cataract. Intraoperatively CCC was incomplete in 4 eyes (4% and had to be converted to canopener capsulotomy. None of the eyes had posterior capsular rupture or zonular dialysis and no eyes were converted to conventional Extra Capsular Cataract Extraction (ECCE. Postoperatively, 6 eyes (6% developed corneal oedema with >10 Descemets folds and 7 eyes (7% had corneal oedema with < 10 Descemets folds. Mild iritis was seen in 6 eyes (6% and moderate iritis with fibrin membrane was seen in 3 eyes (3%. Iridodialysis was observed in 1 eye (1%. Of the 99 patients (99% categorised under good visual outcomes category, 94 patients (94% had a best-corrected visual acuity of 6/9 or better on the 40th post-operative day. CONCLUSION: In developing countries like India where phacoemulsification may not be affordable to a majority of those requiring cataract surgery, MSICS proves to be a safe and efficacious alternative for white cataracts especially with the adjunctive use of trypan blue dye.

  1. Mechanisms involved in quinolone resistance in Mycoplasma mycoides subsp. capri.

    Science.gov (United States)

    Antunes, Nuno T; Assunção, Patrícia; Poveda, José B; Tavío, María M

    2015-06-01

    Mycoplasma mycoides subsp. capri is a causative agent of contagious agalactia in goats. In this study, M. mycoides subsp. capri mutants were selected for resistance to fluoroquinolones (norfloxacin, enrofloxacin and ciprofloxacin) by serial passes in broth with increasing concentrations of antibiotic. Mutations conferring cross-resistance to the three fluoroquinolones were found in the quinolone resistance determining regions of the four genes encoding DNA gyrase and topoisomerase IV. Different mutations in the DNA gyrase GyrA subunit suggest a different mechanism of inhibition between norfloxacin and the other tested fluoroquinolones. The presence of an adenosine triphosphate-dependent efflux system was suggested through the use of the inhibitor orthovanadate. PMID:25951987

  2. Capsulotomy and hydroprocedures for nucleus prolapse in manual small incision cataract surgery.

    Science.gov (United States)

    Venkatesh, Rengaraj; Veena, Kannusamy; Ravindran, Ravilla D

    2009-01-01

    Manual small incision cataract surgery (MSICS) involves the manual removal of nucleus through a scleral tunnel. To achieve 100% success every time, one has to do a good capsulotomy and should master the technique to prolapse the nucleus into anterior chamber. During conversion from extracapsular cataract surgery to MSICS, one can perform a can-opener capsulotomy and prolapse the nucleus. However, it is safer and better to perform a capsulorrhexis and hydroprolapse the nucleus, as it makes the rest of the steps of MSICS comfortable. Use of trypan blue in white and brown cataracts makes the capsulorrhexis and prolapse simple and safe. Extra caution should be taken in cases with hypermature cataracts with weak zonules and subluxated cataracts. PMID:19075402

  3. Capsulotomy and hydroprocedures for nucleus prolapse in manual small incision cataract surgery

    Directory of Open Access Journals (Sweden)

    Venkatesh Rengaraj

    2009-01-01

    Full Text Available Manual small incision cataract surgery (MSICS involves the manual removal of nucleus through a scleral tunnel. To achieve 100% success every time, one has to do a good capsulotomy and should master the technique to prolapse the nucleus into anterior chamber. During conversion from extracapsular cataract surgery to MSICS, one can perform a can-opener capsulotomy and prolapse the nucleus. However, it is safer and better to perform a capsulorrhexis and hydroprolapse the nucleus, as it makes the rest of the steps of MSICS comfortable. Use of trypan blue in white and brown cataracts makes the capsulorrhexis and prolapse simple and safe. Extra caution should be taken in cases with hypermature cataracts with weak zonules and subluxated cataracts.

  4. Kinetics and mechanisms of reactions involving small aromatic reactive intermediates

    Energy Technology Data Exchange (ETDEWEB)

    Lin, M.C. [Emory Univ., Atlanta, GA (United States)

    1993-12-01

    Small aromatic radicals such as C{sub 6}H{sub 5}, C{sub 6}H{sub 5}O and C{sub 6}H{sub 4} are key prototype species of their homologs. C{sub 6}H{sub 5} and its oxidation product, C{sub 6}H{sub 5}O are believed to be important intermediates which play a pivotal role in hydrocarbon combustion, particularly with regard to soot formation. Despite their fundamental importance, experimental data on the reaction mechanisms and reactivities of these species are very limited. For C{sub 6}H{sub 5}, most kinetic data except its reactions with NO and NO{sub 2}, were obtained by relative rate measurements. For C{sub 6}H{sub 5}O, the authors have earlier measured its fragmentation reaction producing C{sub 5}H{sub 5} + CO in shock waves. For C{sub 6}H{sub 4}, the only rate constant measured in the gas phase is its recombination rate at room temperature. The authors have proposed to investigate systematically the kinetics and mechanisms of this important class of molecules using two parallel laser diagnostic techniques--laser resonance absorption (LRA) and resonance enhanced multiphoton ionization mass spectrometry (REMPI/MS). In the past two years, study has been focused on the development of a new multipass adsorption technique--the {open_quotes}cavity-ring-down{close_quotes} technique for kinetic applications. The preliminary results of this study appear to be quite good and the sensitivity of the technique is at least comparable to that of the laser-induced fluorescence method.

  5. EARLY COMPLICATIONS OF CATARACT SURGERY

    Directory of Open Access Journals (Sweden)

    C. Constantin

    2013-06-01

    Full Text Available BACKGROUND: There are different complications of the cataract surgery described in the literature. The impact of these complications on the visual function is in correlation with many factors, some of them being imprecise and unable to be used as prognostic factors before and after the surgery. The modern technique and the surgeon’s experience lowers the complications incidence to a minimum, but even so, some problems cannot be avoided. AIM: The aim of this study is to analyse the early cataract surgery complications for patients operated in 2012 at the Ophthalmology Unit, Railway Hospital, Iaşi. MATERIAL AND METHOD: We conducted a retrospective analysis of the medical records of the patients who underwent cataract surgery in 2012. There were a total of 480 cataract surgeries, the majority of them (92,7% being age related cataracts in different stages of evolution, of which 31.45% being mature cataracts. In 476 eyes, artificial lens was inserted per-primam (474 eyes with posterior chamber intraocular lens and 2 eyes with anterior chamber intraocular lens, in one case the posterior chamber intraocular lens was sutured to the sclera, in 3 cases the eyes remained without lens. RESULTS: The incidence of severe complications or with potential of severe development was: severe corneal oedema 0.83% (4 cases, remaining lens fragments in the vitreous cavity 0.62% (3 cases, toxic anterior segment syndrome (TASS 0.41% (2 cases. There were no endophthalmitis, expulsive haemorhage or retinal detachment after cataract surgery. CONCLUSIONS: The number of early complications of our patients is the same with numbers shown in other studies. With a better surgical technique, a good examination of the patient, a thorough explanation of the procedure to the patient, the use of high quality substances during surgery and proper technology we can lower even more the incidence of the complications.

  6. Mechanisms involved in alternariol-induced cell cycle arrest

    International Nuclear Information System (INIS)

    Alternariol (AOH), a mycotoxin produced by Alternaria sp, is often found as a contaminant in fruit and cereal products. Here we employed the murine macrophage cell line RAW 264.7 to test the hypothesis that AOH causes toxicity as a response to DNA damage. AOH at concentrations of 15–30 μM almost completely blocked cell proliferation. Within 30 min treatment, AOH (30 μM) significantly increased the level of reactive oxygen species (ROS). Furthermore, DNA base oxidations as well as DNA strand breaks and/or alkaline labile sites were detected by the comet assay after 2 h exposure of AOH. Cell death (mostly necrosis) was observed after prolonged exposure to the highest concentration of AOH (60 μM for 24 and 48 h) in our study. The DNA damage response involved phosphorylation (activation) of histone H2AX and check point kinase-1- and 2 (Chk-1/2). Moreover, AOH activated p53 and increased the expression of p21, Cyclin B, MDM2, and Sestrin 2; likewise the level of several miRNA was affected. AOH-induced Sestrin 2 expression was regulated by p53 and could at least partly be inhibited by antioxidants, suggesting a role of ROS in the response. Interestingly, the addition of antioxidants did not inhibit cell cycle arrest. Although the formation of ROS by itself was not directly linked cell proliferation, AOH-induced DNA damage and resulting transcriptional changes in p21, MDM2, and Cyclin B likely contribute to the reduced cell proliferation; while Sestrin 2 would contribute to the oxidant defense.

  7. Mechanisms involved in alternariol-induced cell cycle arrest

    Energy Technology Data Exchange (ETDEWEB)

    Solhaug, A., E-mail: Anita.Solhaug@vetinst.no [Norwegian Veterinary Institute, Oslo (Norway); Vines, L.L. [Michigan State University, Department of Food Science and Human Nutrition, East Lansing, MI (United States); Ivanova, L.; Spilsberg, B. [Norwegian Veterinary Institute, Oslo (Norway); Holme, J.A. [Norwegian Institute of Public Health, Division of Environmental Medicine, Oslo (Norway); Pestka, J. [Michigan State University, Department of Food Science and Human Nutrition, East Lansing, MI (United States); Collins, A. [University of Oslo, Department of Nutrition, Faculty of Medicine, Oslo (Norway); Eriksen, G.S. [Norwegian Veterinary Institute, Oslo (Norway)

    2012-10-15

    Alternariol (AOH), a mycotoxin produced by Alternaria sp, is often found as a contaminant in fruit and cereal products. Here we employed the murine macrophage cell line RAW 264.7 to test the hypothesis that AOH causes toxicity as a response to DNA damage. AOH at concentrations of 15-30 {mu}M almost completely blocked cell proliferation. Within 30 min treatment, AOH (30 {mu}M) significantly increased the level of reactive oxygen species (ROS). Furthermore, DNA base oxidations as well as DNA strand breaks and/or alkaline labile sites were detected by the comet assay after 2 h exposure of AOH. Cell death (mostly necrosis) was observed after prolonged exposure to the highest concentration of AOH (60 {mu}M for 24 and 48 h) in our study. The DNA damage response involved phosphorylation (activation) of histone H2AX and check point kinase-1- and 2 (Chk-1/2). Moreover, AOH activated p53 and increased the expression of p21, Cyclin B, MDM2, and Sestrin 2; likewise the level of several miRNA was affected. AOH-induced Sestrin 2 expression was regulated by p53 and could at least partly be inhibited by antioxidants, suggesting a role of ROS in the response. Interestingly, the addition of antioxidants did not inhibit cell cycle arrest. Although the formation of ROS by itself was not directly linked cell proliferation, AOH-induced DNA damage and resulting transcriptional changes in p21, MDM2, and Cyclin B likely contribute to the reduced cell proliferation; while Sestrin 2 would contribute to the oxidant defense.

  8. Cost effectiveness of second eye cataract surgery

    OpenAIRE

    Frampton, Geoff; Harris, Petra; Cooper, Keith; Lotery, Andrew J; Shepherd, Jonathan

    2014-01-01

    Background Elective cataract surgery is the most commonly performed surgical procedure in the NHS. In bilateral cataracts, the eye with greatest vision impairment from cataract is operated on first. First-eye surgery can improve vision and quality of life. However, it is unclear whether or not cataract surgery on the second eye provides enough incremental benefit to be considered clinically effective and cost-effective. Objective To conduct a systematic review of clinical effectiv...

  9. Simultaneous Penetrating Keratoplasty and Cataract Surgery

    OpenAIRE

    Mohammad-Ali Javadi; Sepehr Feizi; Hamid-Reza Moein

    2013-01-01

    Purpose: To determine the clinical outcomes of simultaneous penetrating keratoplasty (PK), cataract removal and intraocular lens implantation (triple procedure), and to compare the safety and efficacy of two different cataract extraction techniques during the course of PK. Methods: This retrospective comparative study was conducted on patients who had undergone a triple procedure. The technique of cataract extraction was either opensky extracapsular cataract extraction (ECCE) or phacoemul...

  10. Synergistic effect of osmotic and oxidative stress in slow-developing cataract formation.

    Science.gov (United States)

    Chan, Alfred W H; Ho, Ye-shih; Chung, Sookja K; Chung, Stephen S M

    2008-11-01

    Diabetes is a major contributing factor in cataract development. In animal models where cataracts develop within days or weeks of diabetes it is well established that osmotic stress from the accumulation of sorbitol leads to cataract development. This mechanism might explain the rare cases of acute cataract sometimes found in patients with uncontrolled sustained hyperglycemia but cannot account for the vast majority of cataracts that developed after years of diabetes. Thus, a model that can simulate diabetic slow-developing cataract is needed. The contribution of osmotic and oxidative stress in cataract development in sorbitol dehydrogenase (SDH) deficient mice, a model for slow-developing cataract in diabetic patients was determined. Contribution of osmotic stress was assessed by HPLC measurement of sorbitol and by observing the effect of blocking sorbitol accumulation by aldose reductase (AR) null mutation in the SDH deficient mice. Contribution of oxidative stress was assessed by observing the effect of vitamin E treatment and the effect of null mutation of glutathione peroxidase-1 (Gpx-1) on cataract development in these mice. Lenticular sorbitol level was significantly increased in the SDH deficient mice, and blocking sorbitol accumulation by the AR null mutation prevented cataract development, demonstrating the contribution of osmotic stress in cataract development. SDH deficiency did not affect lens oxidative stress status. However, treatment with vitamin E significantly reduced the incidence of cataract, and Gpx-1 deficiency exacerbated cataract development in these mice. Our findings suggest that chronic oxidative stress impaired the osmoregulatory mechanism of the lens. This was not evident until modest increases in lens sorbitol increased the demand of its osmoregulatory function. This osmoregulatory dysfunction model is supported by the fact that the activity of Na+/K+-ATPase, the key regulator of cellular ions and water balance, was dramatically

  11. Are cataracts associated with osteoporosis?

    Directory of Open Access Journals (Sweden)

    Nemet AY

    2013-10-01

    Full Text Available Arie Y Nemet,1 Joel Hanhart,2 Igor Kaiserman,3,4 Shlomo Vinker5,6 1Department of Ophthalmology, Meir Medical Center, Kfar Saba, 2Department of Ophthalmology, Shaare Zedek Medical Center, Jerusalem, 3Department of Ophthalmology, Barzilai Medical Center, Ashkelon, 4Faculty of Health Sciences, Ben Gurion University, Be'er Sheba, 5Department of Family Medicine, Clalit Health Services, Rehovot, 6Department of Family Medicine, Tel Aviv University, Tel Aviv, Israel Background: Calcium is considered an important factor in the development of both osteoporosis and cataract. This study evaluated the association between osteoporosis and cataracts. Objective: To evaluate the prevalence of osteoporosis among patients undergoing cataract surgery, and the association between the two. Patients and methods: This was a retrospective observational case-control study, conducted in the Central District of Clalit Health Services (a district of the largest health maintenance organization in Israel. All Clalit members in the district older than 50 years who underwent cataract surgery from 2000 to 2007 (n=12,984 and 25,968 age- and sex-matched controls comprised the sample. Electronic medical records of all patients in the study were reviewed. The main outcome measure was the prevalence of osteoporosis and the odds ratio of having osteoporosis among cataract patients compared with controls. Results: Demographically, 41.8% were men with a mean age of 68.7 ± 8.2 years. A logistic regression model for osteoporosis showed that age, female sex, higher socioeconomic class, smoking, chronic renal failure, hyperthyroidism, rheumatoid arthritis, inflammatory bowel diseases, and cataract are all associated with increased prevalence of osteoporosis. Obesity is a protective factor for osteoporosis. In all age-groups, osteoporosis was more prevalent in cataract patients than in the control group. Conclusion: Among other well-known risk factors, osteoporosis is associated with the

  12. Anaesthetic Management of Cataract Surgery in a Patient with Sturge-Weber Syndrome

    Directory of Open Access Journals (Sweden)

    Vasantha Kumar

    2015-05-01

    Full Text Available Sturge-Weber Syndrome (SWS, also called as encephalo trigeminal angiomatosis, is a rare congenital syndrome, characterized by lepto meningeal haemangioma, a facial port-wine stains distributed over the trigeminal nerve area, (usually involving one side and glaucoma. During cataract surgery, there may be rupture of choroid haemangioma, leading to excessive bleeding, or of haemangioma involving the airway, leading to difficult mask ventilation, laryngoscopy and intubation. We discuss the anaesthetic management of the patient with SWS for cataract surgery.

  13. Mechanism involved in enhancement of osteoblast differentiation by hyaluronic acid

    Energy Technology Data Exchange (ETDEWEB)

    Kawano, Michinao [Division of Maxillofacial Diagnostic and Surgical Science, Department of Oral and Maxillofacial Surgery, Kyushu Dental College, Kitakyushu 803-8580 (Japan); Division of Infections and Molecular Biology, Department of Health Promotion, Kyushu Dental College, Kitakyushu 803-8580 (Japan); Ariyoshi, Wataru [Division of Infections and Molecular Biology, Department of Health Promotion, Kyushu Dental College, Kitakyushu 803-8580 (Japan); Iwanaga, Kenjiro [Division of Maxillofacial Diagnostic and Surgical Science, Department of Oral and Maxillofacial Surgery, Kyushu Dental College, Kitakyushu 803-8580 (Japan); Okinaga, Toshinori [Division of Infections and Molecular Biology, Department of Health Promotion, Kyushu Dental College, Kitakyushu 803-8580 (Japan); Habu, Manabu [Division of Maxillofacial Diagnostic and Surgical Science, Department of Oral and Maxillofacial Surgery, Kyushu Dental College, Kitakyushu 803-8580 (Japan); Yoshioka, Izumi [Division of Oral and Maxillofacial Surgery, Department of Medicine of Sensory and Motor Organs, University of Miyazaki, Kiyotake, Miyazaki 889-1692 (Japan); Tominaga, Kazuhiro [Division of Maxillofacial Diagnostic and Surgical Science, Department of Oral and Maxillofacial Surgery, Kyushu Dental College, Kitakyushu 803-8580 (Japan); Oral Bioresearch Center, Kyushu Dental College, Kitakyushu 803-8580 (Japan); Nishihara, Tatsuji, E-mail: tatsujin@kyu-dent.ac.jp [Division of Infections and Molecular Biology, Department of Health Promotion, Kyushu Dental College, Kitakyushu 803-8580 (Japan); Oral Bioresearch Center, Kyushu Dental College, Kitakyushu 803-8580 (Japan)

    2011-02-25

    Research highlights: {yields} In this study was to investigate the effects of HA on osteoblast differentiation induced by BMP-2. {yields} MG63 cells were incubated with BMP-2 and HA for various time periods. {yields} Phosphorylation of Smad 1/5/8, p38, and ERK proteins was determined by western blot analysis. To elucidate the nuclear translocation of phosphorylated Smad 1/5/8, stimulated cells were subjected to immunofluorescence microscopy. {yields} HA enhanced BMP-2 induces osteoblastic differentiation in MG63 cells via down-regulation of BMP-2 antagonists and ERK phosphorylation. -- Abstract: Objectives: Bone morphogenetic protein-2 (BMP-2) is expected to be utilized to fill bone defects and promote healing of fractures. However, it is unable to generate an adequate clinical response for use in bone regeneration. Recently, it was reported that glycosaminoglycans, including heparin, heparan sulfate, keratan sulfate, dermatan sulfate, chondroitin-4-sulfate, chondroitin-6-sulfate, and hyaluronic acid (HA), regulate BMP-2 activity, though the mechanism by which HA regulates osteogenic activities has not been fully elucidated. The aim of this study was to investigate the effects of HA on osteoblast differentiation induced by BMP-2. Materials and methods: Monolayer cultures of osteoblastic lineage MG63 cells were incubated with BMP-2 and HA for various time periods. To determine osteoblastic differentiation, alkaline phosphatase (ALP) activity in the cell lysates was quantified. Phosphorylation of Smad 1/5/8, p38, and ERK proteins was determined by Western blot analysis. To elucidate the nuclear translocation of phosphorylated Smad 1/5/8, stimulated cells were subjected to immunofluorescence microscopy. To further elucidate the role of HA in enhancement of BMP-2-induced Smad signaling, mRNA expressions of the BMP-2 receptor antagonists noggin and follistatin were detected using real-time RT-PCR. Results: BMP-2-induced ALP activation, Smad 1/5/8 phosphorylation, and

  14. Mechanism involved in enhancement of osteoblast differentiation by hyaluronic acid

    International Nuclear Information System (INIS)

    Research highlights: → In this study was to investigate the effects of HA on osteoblast differentiation induced by BMP-2. → MG63 cells were incubated with BMP-2 and HA for various time periods. → Phosphorylation of Smad 1/5/8, p38, and ERK proteins was determined by western blot analysis. To elucidate the nuclear translocation of phosphorylated Smad 1/5/8, stimulated cells were subjected to immunofluorescence microscopy. → HA enhanced BMP-2 induces osteoblastic differentiation in MG63 cells via down-regulation of BMP-2 antagonists and ERK phosphorylation. -- Abstract: Objectives: Bone morphogenetic protein-2 (BMP-2) is expected to be utilized to fill bone defects and promote healing of fractures. However, it is unable to generate an adequate clinical response for use in bone regeneration. Recently, it was reported that glycosaminoglycans, including heparin, heparan sulfate, keratan sulfate, dermatan sulfate, chondroitin-4-sulfate, chondroitin-6-sulfate, and hyaluronic acid (HA), regulate BMP-2 activity, though the mechanism by which HA regulates osteogenic activities has not been fully elucidated. The aim of this study was to investigate the effects of HA on osteoblast differentiation induced by BMP-2. Materials and methods: Monolayer cultures of osteoblastic lineage MG63 cells were incubated with BMP-2 and HA for various time periods. To determine osteoblastic differentiation, alkaline phosphatase (ALP) activity in the cell lysates was quantified. Phosphorylation of Smad 1/5/8, p38, and ERK proteins was determined by Western blot analysis. To elucidate the nuclear translocation of phosphorylated Smad 1/5/8, stimulated cells were subjected to immunofluorescence microscopy. To further elucidate the role of HA in enhancement of BMP-2-induced Smad signaling, mRNA expressions of the BMP-2 receptor antagonists noggin and follistatin were detected using real-time RT-PCR. Results: BMP-2-induced ALP activation, Smad 1/5/8 phosphorylation, and nuclear translocation

  15. [Keratoplasty combined with cataract surgery].

    Science.gov (United States)

    Muraine, M; Gueudry, J; Retout, A; Genevois, O

    2012-09-01

    Corneal pathologies leading to keratoplasty are often associated with cataract and combined surgery is therefore mandatory. Triple procedure with penetrating keratoplasty and concurrent cataract extraction followed by intra ocular lens (IOL) implantation is usually the preferential choice because visual rehabilitation is theoretically more rapid. Surgeons have to be aware of surgical conditions during open-sky surgery because vitreous pressure is not counterbalanced by anterior chamber pressure. Today, many surgeons prefer non-simultaneous procedures with cataract surgery performed months after grafting because of the improvement in spherical refractive error. More recently, new triple procedures, Descemet's stripping automated keratoplasty and concurrent cataract surgery have gained popularity, especially in patients with Fuchs dystrophy associated with cataract. Surgery starts with phacoemulsification, followed by endothelium exchange through a 3 to 5 mm incision. Advantages against classic triple procedure are quick visual rehabilitation, fewer induced refractive errors, minimal postoperative discomfort and corneal integrity. Surgeons have to consider an eventual postoperative hyperopic shift secondary to corneal lenticule shape when choosing adequate intraocular lens. PMID:22921023

  16. Paediatric cataract implant surgery outcome

    Directory of Open Access Journals (Sweden)

    Istiantoro Istiantoro

    2003-03-01

    Full Text Available This study evaluated the surgical outcome of various surgical technique in paediatric cataract implant surgery, at Jakarta Eye Center, Jakarta, Indonesia. This was a retrospective study of 57 eyes in 44 children who had primary cataract implants surgery. Three surgical techniques used were : 1. Extracapsular cataract extraction with intraocular lens implantation with intact posterior capsule which was performed on 21 eyes (group 1. 2. Extracapsular cataract extraction with intraocular lens implantation and posterior capsulorhexis (PCCC and optic capture which was performed on 24 eyes (group 2. 3. Extracapsular cataract extraction with intra­ocular lens implantation, posterior capsulorhexis and anterior vitrectomy which was performed on 24 eyes (group 3. All patients were followed up more than one year. Our results showed that posterior capsule opacity (PCO was developed in 20 eyes with intact capsules in group 1. All eyes had a clear visual axis in group 2. PCO developed only in one eye in group 3. In conclusion,  PCCC and optic capture with or without anterior vitrectomy are effective methods in preventing PCO in infant and children. (Med J Indones 2003; 12: 21-6Keywords: posterior capsule opacification, posterior capsulorhexis, optic capture, anterior vitrectomy

  17. Mechanism(S) Involved in the Colon-Specific Expression of the Thiamine Pyrophosphate (Tpp) Transporter

    Science.gov (United States)

    Nabokina, Svetlana M.; Ramos, Mel Brendan; Said, Hamid M.

    2016-01-01

    Microbiota of the large intestine synthesizes considerable amount of vitamin B1 (thiamine) in the form of thiamine pyrophosphate (TPP). We have recently demonstrated the existence of an efficient and specific carrier-mediated uptake process for TPP in human colonocytes, identified the TPP transporter (TPPT) involved (product of the SLC44A4 gene), and shown that expression of TPPT along the gastrointestinal (GI) tract is restricted to the colon. Our aim in this study was to determine the molecular basis of the colon-specific expression of TPPT focusing on a possible epigenetic mechanism. Our results showed that the CpG island predicted in the SLC44A4 promoter is non-methylated in the human colonic epithelial NCM460 cells, but is hyper-methylated in the human duodenal epithelial HuTu80 cells (as well as in the human retinal pigment epithelial ARPE19 cells). In the mouse (where TPPT expression in the GI tract is also restricted to the colon), the CpG island predicted in the Slc44a4 promoter is non-methylated in both the jejunum and colon, thus arguing against possible contribution of DNA methylation in the colon-specific expression of TPPT. A role for histone modifications in the tissue-specific pattern of Slc44a4 expression, however, was suggested by the findings that in mouse colon, histone H3 in the 5’-regulatory region of Slc44a4 is tri-methylated at lysine 4 and acetylated at lysine 9, whereas the tri-methylation at lysine 27 modification was negligible. In contrast, in the mouse jejunum, histone H3 is hyper-trimethylated at lysine 27 (repressor mark). Similarly, possible involvement of miRNA(s) in the tissue-specific expression of TPPT was also suggested by the findings that the 3’-UTR of SLC44A4 is targeted by specific miRNAs/RNA binding proteins in non-colonic, but not in colonic, epithelial cells. These studies show, for the first time, epigenetic mechanisms (histone modifications) play a role in determining the tissue-specific pattern of expression of

  18. Low-Dose Radiation Cataract and Genetic Determinants of Radiosensitivity

    Energy Technology Data Exchange (ETDEWEB)

    Kleiman, Norman Jay [Columbia University

    2013-11-30

    The lens of the eye is one of the most radiosensitive tissues in the body. Ocular ionizing radiation exposure results in characteristic, dose related, progressive lens changes leading to cataract formation. While initial, early stages of lens opacification may not cause visual disability, the severity of such changes progressively increases with dose until vision is impaired and cataract extraction surgery may be required. Because of the transparency of the eye, radiation induced lens changes can easily be followed non-invasively over time. Thus, the lens provides a unique model system in which to study the effects of low dose ionizing radiation exposure in a complex, highly organized tissue. Despite this observation, considerable uncertainties remain surrounding the relationship between dose and risk of developing radiation cataract. For example, a growing number of human epidemiological findings suggest significant risk among various groups of occupationally and accidentally exposed individuals and confidence intervals that include zero dose. Nevertheless, questions remain concerning the relationship between lens opacities, visual disability, clinical cataract, threshold dose and/or the role of genetics in determining radiosensitivity. Experimentally, the response of the rodent eye to radiation is quite similar to that in humans and thus animal studies are well suited to examine the relationship between radiation exposure, genetic determinants of radiosensitivity and cataractogenesis. The current work has expanded our knowledge of the low-dose effects of X-irradiation or high-LET heavy ion exposure on timing and progression of radiation cataract and has provided new information on the genetic, molecular, biochemical and cell biological features which contribute to this pathology. Furthermore, findings have indicated that single and/or multiple haploinsufficiency for various genes involved in DNA repair and cell cycle checkpoint control, such as Atm, Brca1 or Rad9

  19. Cataract formation following vitreoretinal procedures

    Directory of Open Access Journals (Sweden)

    Feng H

    2014-09-01

    Full Text Available Hao Feng, Ron A Adelman Department of Ophthalmology and Visual Science, Yale University School of Medicine, New Haven, CT, USA Purpose: To evaluate the incidence and prevalence of cataract formation, progression, and extraction in patients that underwent vitreoretinal procedures and to evaluate factors that can potentially predispose patients to postoperative cataracts.Materials and methods: The medical records of consecutive patients who underwent vitreoretinal surgery at the Yale Eye Center with at least 6 months of follow-up and no prior intraocular surgery were obtained. Preoperative, intraoperative, and postoperative data were recorded and analyzed in this retrospective observational study. The main outcome measures were defined as cataract extraction, formation, and progression after vitreoretinal procedures. The lens status of the surgical eye was recorded preoperatively and at 1 month, 3 months, 6 months, 12 months, 24 months, and 36 months postoperatively.Results: A total of 193 eyes of 180 patients fulfilled the inclusion criteria. The percentages of eyes with mild lens change were 96% after 20-gauge pars plana vitrectomy (PPV, 72% after small gauge (23- and 25-gauge PPV, 38% after scleral buckle (SB, 38% after pneumatic retinopexy (PR, and 91% after PPV plus SB (PPV+SB. Posterior subcapsular and nuclear sclerotic cataracts were the most common with almost all developing within 24 months. There was no statistically significant difference (P=1.00 between the rate of cataract extraction after 20-gauge (41% and small gauge PPV (42%, but there was a statistically significant difference between PPV and non-PPV (SB, 6%; PR, 7%; P<0.001 and PPV and PPV+SB groups (69%; P=0.0063.Conclusion: Cataracts were common following PPV regardless of the gauge. SB and PR led to the lowest while PPV+SB led to the highest risk of postoperative cataracts. Keywords: cataracts, vitreoretinal surgery, vitrectomy, scleral buckle, pneumatic retinopexy

  20. Perceptions of patients about cataract

    Directory of Open Access Journals (Sweden)

    Oliveira Regina de Souza Carvalho de Salles

    2005-01-01

    Full Text Available OBJECTIVE: To identify in adult patients suffering from cataract the perceptions regarding the disease and its surgical treatment. MATERIALS AND METHODS: An exploratory survey was conducted among adult patients suffering from cataract and participating in a large-scale cataract management program at the University of São Paulo General Hospital in 2004. The interviews were conducted by research assistants previously trained to pose questions and record answers. RESULTS: The sample consisted of 170 men and women (43.5% and 56.5%, respectively, aged between 40 and 88 years. Of the 170 participants, 43.5% were from the State of São Paulo, 14.7% from the State of Bahia, 12.4% from the State of Minas Gerais, 5.9% from the State of Pernambuco, 1.8% from other countries, and the remaining 21.7% were from other Brazilian states. Of those who were actively working (n = 87, 43.7% had an occupational level corresponding to nonspecialized manual labor, 27.6% were in specialized manual labor jobs, 25.3% had routine nonmanual occupations, 1.1% supervised manual labor, and 2.3% had low-ranking supervision or inspection jobs over nonmanual occupations. Of those who were not actively working (n = 82, 53.6% were retired, 45.2% were housewives, and 1.2% were unemployed. Concerning conceptions about cataract, 79.0% referred to it as "a small skin fold that gradually covers the eye" and 32.4% mentioned, in addition, other conceptions. Concerning the cause, of the alternatives presented to them, 80% reported aging, 47.1% blamed "overusing the eyes in the workplace or at home", 7.1% believed they had cataract due to some kind of "spell." Of the associated answers, 94.1% referred to "blurred vision" in people suffering from cataract, 72.4% thought the person may become blind, and 66.5% believed that the patients suffering from cataract are depressed because they cannot see. Regarding surgery, 28.8% were afraid of undergoing surgery; of those, 16.3% cited with the fear

  1. Immediate Sequential Bilateral Cataract Surgery

    DEFF Research Database (Denmark)

    Kessel, Line; Andresen, Jens; Erngaard, Ditte; Flesner, Per; Tendal, Britta; Hjortdal, Jesper

    2015-01-01

    performed using the Cochrane Review Manager software. The quality of the evidence was assessed using the GRADE method (Grading of Recommendation, Assessment, Development, and Evaluation). We did not find any difference in the risk of complications or visual outcome in patients randomized to ISBCS or surgery......-based national Danish guidelines for cataract surgery. A systematic literature review in PubMed, Embase, and Cochrane central databases identified three randomized controlled trials that compared outcome in patients randomized to ISBCS or bilateral cataract surgery on two different dates. Meta-analyses were...

  2. Natural therapies for ocular disorders, part two: cataracts and glaucoma.

    Science.gov (United States)

    Head, K A

    2001-04-01

    Pathophysiological mechanisms of cataract formation include deficient glutathione levels contributing to a faulty antioxidant defense system within the lens of the eye. Nutrients to increase glutathione levels and activity include lipoic acid, vitamins E and C, and selenium. Cataract patients also tend to be deficient in vitamin A and the carotenes, lutein and zeaxanthin. The B vitamin riboflavin appears to play an essential role as a precursor to flavin adenine dinucleotide (FAD), a co-factor for glutathione reductase activity. Other nutrients and botanicals, which may benefit cataract patients or help prevent cataracts, include pantethine, folic acid, melatonin, and bilberry. Diabetic cataracts are caused by an elevation of polyols within the lens of the eye catalyzed by the enzyme aldose reductase. Flavonoids, particularly quercetin and its derivatives, are potent inhibitors of aldose reductase. Glaucoma is characterized by increased intraocular pressure (IOP) in some but not all cases. Some patients with glaucoma have normal IOP but poor circulation, resulting in damage to the optic nerve. Faulty glycosaminoglycan (GAG) synthesis or breakdown in the trabecular meshwork associated with aqueous outflow has also been implicated. Similar to patients with cataracts, those with glaucoma typically have compromised antioxidant defense systems as well. Nutrients that can impact GAGs such as vitamin C and glucosamine sulfate may hold promise for glaucoma treatment. Vitamin C in high doses has been found to lower IOP via its osmotic effect. Other nutrients holding some potential benefit for glaucoma include lipoic acid, vitamin B12, magnesium, and melatonin. Botanicals may offer some therapeutic potential. Ginkgo biloba increases circulation to the optic nerve; forskolin (an extract from Coleus forskohlii) has been used successfully as a topical agent to lower IOP; and intramuscular injections of Salvia miltiorrhiza have shown benefit in improving visual acuity and

  3. CATARACT SURGERY IN PSEUDOEXFOLIATION SYNDROME

    Directory of Open Access Journals (Sweden)

    Abbin George

    2014-10-01

    Full Text Available Pseudoexfoliation (PEX syndrome is an age-related systemic disorder with major ocular manifestations. It is characterized by the production and deposition of fibrillogranular amyloid-like extracellular material within many ocular tissues. Pseudoexfoliation is also a risk factor for glaucoma and also correlated to an increased incidence of cataract formation. Cataract surgery in eyes with pseudoexfoliation is connected with many complications and presents challenges that require careful preoperative planning and intraoperative care to ensure safe surgery and successful postoperative outcome. Zonular weakness and poor pupillary dilation are the two major risk factors for surgical complications and poor visual acuity after surgery. With proper preparation and the use of specialized adjunctive devices, phacoemulsification is the preferred procedure of cataract extraction in this group of patients. Postoperatively, patients require frequent and detailed follow-up to monitor for complications such as intraocular pressure rise, inflammation and intraocular lens dislocation. In conclusion, with appropriate preoperative, intraoperative and postoperative care, the risk of complications can be minimized and favorable outcomes may be achieved in cataract surgery in eyes with pseudoexfoliation syndrome.

  4. Driving When You Have Cataracts

    Science.gov (United States)

    ... when they want. I Driving is a complex skill. Our ability to drive safely can be challenged by changes in our ... drive with you to see how well you drive with your cataract. I The ... to improve your driving skills. Improving your skills could help keep you and ...

  5. Capsulotomy and hydroprocedures for nucleus prolapse in manual small incision cataract surgery

    OpenAIRE

    Venkatesh Rengaraj; Veena Kannusamy; Ravindran Ravilla

    2009-01-01

    Manual small incision cataract surgery (MSICS) involves the manual removal of nucleus through a scleral tunnel. To achieve 100% success every time, one has to do a good capsulotomy and should master the technique to prolapse the nucleus into anterior chamber. During conversion from extracapsular cataract surgery to MSICS, one can perform a can-opener capsulotomy and prolapse the nucleus. However, it is safer and better to perform a capsulorrhexis and hydroprolapse the nucleus, as it ma...

  6. The journey to femtosecond laser-assisted cataract surgery: new beginnings or a false dawn?

    OpenAIRE

    Trikha, S; Turnbull, A M J; Morris, R.J.; Anderson, D F; Hossain, P.

    2013-01-01

    Femtosecond laser-assisted cataract surgery (FLACS) represents a potential paradigm shift in cataract surgery, but it is not without controversy. Advocates of the technology herald FLACS as a revolution that promises superior outcomes and an improved safety profile for patients. Conversely, detractors point to the large financial costs involved and claim that similar results are achievable with conventional small-incision phacoemulsification. This review provides a balanced and comprehensive ...

  7. Preoperative corneal astigmatism among adult patients with cataract in Northern Nigeria

    OpenAIRE

    Mohammed Isyaku; Ali, Syed A.; Sadiq Hassan

    2014-01-01

    The prevalence and nature of corneal astigmatism among patients with cataract has not been well-documented in the resident African population. This retrospective study was undertaken to investigate preexisting corneal astigmatism in adult patients with cataract. We analyzed keratometric readings acquired by manual Javal-Schiotz keratometry before surgery between January 1, 2011 and December 31, 2011. There were 3,169 patients (3286 eyes) aged between 16 and 110 years involved with a Male to f...

  8. Matrix Metalloproteinase Inhibitors Suppress Transforming Growth Factor-β-Induced Subcapsular Cataract Formation

    OpenAIRE

    Dwivedi, Dhruva J.; Pino, Giuseppe; Banh, Alice; Nathu, Zahra; Howchin, Derek; Margetts, Peter; Sivak, Jacob G.; West-Mays, Judith A.

    2006-01-01

    The pleotropic morphogen transforming growth factor-β (TGFβ) plays an important role in the development of fibrotic pathologies, including anterior subcapsular cataracts (ASCs). ASC formation involves increased proliferation and transition of lens epithelial cells into myofibroblasts, through epithelial-mesenchymal transformation that results in opaque plaques beneath the lens capsule. In this study, we used a previously established TGFβ-induced rat cataract model to explore the role of matri...

  9. Schlieren visualization of fluid dynamics phenomena during phacosonication in cataract surgery

    Science.gov (United States)

    Serafino, Gabriella; Piuzzi, Barbara; Sanguinetti, G.; Sirotti, C.; Sirotti, Paolo; Tognetto, D.

    2005-03-01

    In ultrasonic phacoemulsification during cataract surgery the lens material fragmentation has been described as being caused by a combination of several mechanisms. The different theories involve tip vibration, acoustic waves produced by the tip, particles and liquids impact on the surface of the lens and cavitation. However the mechanisms are still not clear. To better understand phaco-related phenomena we have tried to produce a description in term of images of the cataract phacoemulsification procedure. An expanded and collimated laser diode beam transilluminates a transparent tube containing a liquid medium. The machine is activated separating the different phases of irrigation, aspiration and phacosonication. Fluid turbulences and phenomena related to the tip vibration constitute the phase images, visualized using Schlieren or similar techniques. The optical Fourier transform is filtered by a blade or by a black dot. The filtered transform is reconstructed into the visualized phase image and this is acquired by a digital image processing system. The presence of acoustic cavitation and possibly of ultrasonic radiation has been revealed. The technique promises to be a possible means for evaluation of single phaco apparatus power setting and comparison between different machines in terms of power modulation and cavitation production.

  10. Phacolytic glaucoma-its treatment by planned extracapsular cataract extraction with posterior chamber intraocular lens implantation

    OpenAIRE

    Singh Gurdeep; Kaur Jagmeet; Mall Sanjay

    1994-01-01

    Phacolytic glaucoma has traditionally been treated with intracapsular lens extraction to avoid any anaphylaxis. Various mechanisms have been described for the rise of intraocular pressure in these cases. The present study was undertaken to evaluate the response of extracapsular cataract extraction (ECCE) with posterior chamber intraocular lens implantation (PC IOL) in five cases of phacolytic glaucoma that occurred between March 1989 and August 1990. A planned extracapsular cataract extractio...

  11. Visual acuity testing in cataract-An insight (cataract classification density based.

    Directory of Open Access Journals (Sweden)

    Angra S

    1990-01-01

    Full Text Available The senile cataracts have been graded on the basis of density objectively. The letter visual acuity, laser interferometric visual acuity and pin hole visual acuity were compared in various grades of cataracts and controls (phakic and aphakic in 140 eyes. It was found that good correlation exists in all eyes except when cataract density is grade III or IV. The laser interferometry has good prognostic value when the predictability is assessed in early stages of cataract (Grade I & II.

  12. Cost-effectiveness analysis of cataract surgery with intraocular lens implantation: extracapsular cataract extraction versus phacoemulsification

    OpenAIRE

    Mohd R.A. Manaf; Aljunid, Syed M; Faridah H. Annuar; Chuah K. Leong; Normalina Mansor

    2007-01-01

    A randomized single blinded clinical trial to compare the cost-effectiveness of cataract surgery between extracapsular cataract extraction (ECCE) and phacoemulsification (PEA) was conducted at Hospital Universiti Kebangsaan Malaysia (HUKM) from March 2000 until August 2001. The cost of a cataract surgery incurred by hospital, patients and households were calculated preoperatively, one week, two months (for both techniques) and six months (for ECCE only). Effectiveness of cataract surgery was ...

  13. Long-Term Results of Cataract Surgery in Patients with Unilateral Childhood Cataract

    OpenAIRE

    Suzan Güven Yılmaz; Duygu İnci Bozbıyık; Süheyla Köse; Önder Üretmen

    2012-01-01

    Pur po se: To evaluate the long-term visual outcome and to determine the surgical complications after cataract surgery in patients with unilateral childhood cataract. Ma te ri al and Met hod: We retrospectively reviewed the records of 18 cases with unilateral childhood cataract who had undergone cataract surgery before the age of seven. Primary intraocular lens (IOL) implantation was made in children who were older than 1 year of age. Secondary IOL implantation was made after 18 m...

  14. Quality of care from the perspective of the cataract patient: QUOTE Cataract Questionnaire.

    OpenAIRE

    Nijkamp, M D; Sixma, H.J.; Afman, H.; Hiddema, F; Koopmans, S.A.; Borne, B. van den; Hendrikse, F.; Nuijts, R M M A

    2002-01-01

    PURPOSE: To examine the potential of a questionnaire (QUOTE Cataract) to measure quality of care from the perspective of cataract patients in quality-assurance or improvement programs. SETTING: Department of Ophthalmology, University Hospital Maastricht, Maastricht, University Hospital Groningen, Groningen, and Rotterdam Eye Hospital, Rotterdam, The Netherlands. METHODS: Cataract patients (N = 540) who had cataract surgery 2 to 8 months previously rated 31 quality-of-care aspects in terms of ...

  15. Cataract and ionizing radiation; Cataracte et rayonnements ionisants

    Energy Technology Data Exchange (ETDEWEB)

    Wassilieff, S. [Ecole des Applications Militaires de l' Energie Atomique, 50 - Cherbourg Octeville (France)

    2009-10-15

    The radiation-induced cataract has been up to now considered as a quite rare pathology, needing high-dose radiations (beyond a dose threshold roughly estimated at 2 Grays to the lens) consisting mainly in head tumour radiotherapy complications. Several new studies on different exposed populations such as astronauts, japanese atomic bomb survivors, people undergoing X-ray examinations, Chernobyl accident 'liquidators' as well as data from animal experiments, suggest that dose threshold for detectable opacities as well as for clinical posterior sub-capsular cataract occurring, might be far lower than those previously assumed. Even the existence of a dose threshold is no longer an absolute certitude insofar as radiation-induced cataract pathogenesis might consist not really in a deterministic effect (direct tissue harmful effect, killing or seriously injuring a critical population of cells) as believed until now, but rather in a stochastic effect (genomic damage in target-cells, altered cell division, abnormal lens fiber cell differentiation). More practically, these new data may lead us to reconsider radioprotection of specifically exposed populations: mainly patients and workers. Regarding workers, labour legislation (lens equivalent dose limit of 150 mSv during 12 consecutive months) might be, in the medium term, reassessed downwards. (author)

  16. Cataracts in patients injected with 224Ra

    International Nuclear Information System (INIS)

    Cataracts were reported as of June 1984, by 6% (12/218) of patients injected with 224Ra as juveniles and by 5% (32/681) injected as adults. The high incidence among those injected as juveniles is unusual and their subsequent ages, when reporting the cataracts, averaged only 34 years (range 14-46 years). In the juveniles of known dosage receiving more than 28 μCi 224Ra/kg, the cataract incidence was 14% (11/80) compared to only 0.8% (1/131) below 28 μ Ci 224Ra/kg. The cataract incidence increased significantly with dosage in the juveniles and in the adults. The appearance of these cataracts, as viewed by slitlamp biomicroscopy or in histological sections, is described. The appearance did not differ from classical radiation cataract in principle. (orig.)

  17. The cataract response in radium 224 patients

    International Nuclear Information System (INIS)

    A group of 831 patients were studied, after injection with known dosages of radium 224 in Germany shortly after the Second World War. From a total of 58 cataract diagnoses, 25 occurred before the age of 54. Data consist of ophthalmological reports from examinations after vision impairment. Mathematical analysis suggests that almost all of the 25 early cataracts and a substantial part of the later cataracts are treatment-related. The probability of induction of severe cataracts is roughly proportional to the square of the dosage, that is, the radium 224 activity per unit body weight, and also to the square of the time after treatment. An extended analysis also accounts for spontaneous cataracts; this shows for the spontaneous cataracts a probability that increases with roughly the eighth power of the age. (author)

  18. Simulation-based certification for cataract surgery

    DEFF Research Database (Denmark)

    Thomsen, Ann Sofia Skou; Kiilgaard, Jens Folke; Kjaerbo, Hadi; la Cour, Morten; Konge, Lars

    2015-01-01

    PURPOSE: To evaluate the EyeSi(™) simulator in regard to assessing competence in cataract surgery. The primary objective was to explore all simulator metrics to establish a proficiency-based test with solid evidence. The secondary objective was to evaluate whether the skill assessment was specific...... to cataract surgery. METHODS: We included 26 ophthalmic trainees (no cataract surgery experience), 11 experienced cataract surgeons (>4000 cataract procedures) and five vitreoretinal surgeons. All subjects completed 13 different modules twice. Simulator metrics were used for the assessments. RESULTS......: Total module score on seven of 13 modules showed significant discriminative ability between the novices and experienced cataract surgeons. The intermodule reliability coefficient was 0.76 (p < 0.001). A pass/fail level was defined from the total score on these seven modules using the contrasting...

  19. On the delights of being an ex-cataract patient: Visual experiences before and after cataract operations; what they indicate

    Science.gov (United States)

    van Nes, Floris L.

    2014-02-01

    This paper is about changes in the author's visual perception over most of his lifetime, but in particular in the period before and after cataract operations. The author was myopic (-3D) until the operations, and emmetropic afterwards - with mild astigmatic aberrations that can be compensated with cylindrical spectacles, but in his case rarely are, because of the convenience of not needing to wear distance glasses in daily life anymore. The perceptual changes concern color vision, stereopsis and visual acuity. The post-cataract changes were partly expected, for example less yellow and more blue images, but partly wholly unexpected, and accompanied by feelings of excitement and pleasure; even delight. These unexpected changes were a sudden, strongly increased depth vision and the sensation of seeing suddenly sharper than ever before, mainly at intermediate viewing distances. The visual acuity changes occur after, exceptionally, his distance glasses are put on. All these sensations lasted or last only for a short time. Those concerning stereopsis were dubbed 'super depth', and were confined to the first two months after the second cataract operation. Those concerning acuity were termed 'super-sharpness impression'; SSI. These can be elicited more or less at will, by putting on the spectacles described; but will then disappear again, although the spectacles are kept on. Ten other ex-cataract patients have been interviewed on their post-operation experiences. The 'super-depth' and SSI experiences may be linked to assumed neurophysiological mechanisms such as the concept of Bayesian reweighting of perceptual criteria.

  20. Pseudoexfoliation - A Dreaded Nightmare in Cataract Surgery

    OpenAIRE

    Kar, Sushil Kumar; Bhuyan, Lopamudra; Nanda, Ashok Kumar

    2015-01-01

    Aim: Pseudoexfoliation (PXE) is a common and clinically important systemic condition in elderly people that affects the outcome of cataract surgery. It can cause various complications during cataract surgery due to pupillary rigidity and zonular weakness and instability. The purpose of this study was to evaluate the frequency and types of complications of Phacoemulsification in patients with cataract and PXE.Materials and Methods: This cross sectional, prospective study was carried out on 60 ...

  1. Evaluation of Cataract Preventive Action of Phycocyanin

    OpenAIRE

    Kothadia AD; AM Shenoy; Shabaraya AR; Rajan MS; UM Viradia; Patel NH

    2011-01-01

    Phycocyanin is a biliprotein pigment found in blue-green algae Spirulina platensis, which have attracted attention because of their nutritional value and medicinal properties. This pigment has antioxidant, anti-inflammatory and hepatoprotective activity in different experimental models. This data supports the view that phycocyanin may prevent cataract progression. Cataract preventive action of phycocyanin was evaluated against naphthalene and galactose induced cataract experimental models in ...

  2. Regression of Labrador keratopathy following cataract extraction.

    OpenAIRE

    Dahan, E; Judelson, J; Welsh, N H

    1986-01-01

    Labrador keratopathy (LK) is an acquired corneal degeneration thought to be caused by chronic exposure to solar irradiation. Reports so far suggest that it is a progressive or at least a stationary condition. There are no detailed reports on recommended therapy. A prospective clinical study was conducted to show regression of LK following extracapsular cataract extraction. Seventeen black patients (26 eyes) with LK and mature cataracts underwent extracapsular cataract extraction. The severity...

  3. Ultraviolet radiation cataract development and ascorbate supplementation

    OpenAIRE

    Mody, Vino C Jr

    2008-01-01

    Background: Cataract is the major cause of blindness in the world, and long-term solar ultraviolet radiation (UVR) is a major risk factor. The pathogenesis of UVRinduced cataract is studied in various animal models and cell systems. The significance of oxidation processes in cataract and other eye diseases has made the study of protective antioxidants increasingly important. Ascorbate, or vitamin C, is an important dietary antioxidant and essential nutrient in the human and ...

  4. Sutureless Cataract Surgery: Principles and Steps

    OpenAIRE

    John Sandford-Smith

    2003-01-01

    Introduction. Cataracts cause about 50% of world blindness. There is little likelihood of effective prevention becoming available in the next few years and so the only treatment will remain surgical. For many of the other major causes of world blindness, like trachoma, xerophthalmia and onchocerciasis, the remedy is community-based, not hospital-based, and requires prevention rather than treatment. The prevalence of blinding cataract will only increase as people live longer, so cataract will ...

  5. The cataract response in radium 224 patients

    International Nuclear Information System (INIS)

    Enhanced incidence of severe cataracts has been observed in a group of 831 patients injected with Ra224 in Germany shortly after the 1939-45 war. From 58 diagnoses 25 occurred before the age of 54. There was a strong correlation between observed incidence and injected activity. Almost all the 25 early cataracts, and a substantial number of the later could be treatment-related. The probability of induction of severe cataracts is roughly proportional to the square of the time after treatment. Extended analysis also accounts for spontaneous cataracts, a probability increasing with roughly the eighth power of the age. (UK)

  6. [History of cataract operations in Hungary].

    Science.gov (United States)

    Marsovszky, László

    2013-11-10

    The history of the cataract operations dates back to thousands of years ago. Initially, surgery was carried out using rudimentary operating techniques resulting in the loss of many eyes. Cataract surgery has evolved immersely and now it is a highly refined surgical practice. Evolution of the cataract surgery was closely linked to broadening of anatomical-pathological knowledge and to the development of the instruments applied. Although Daviel performed the first intentional cataract removal in 1747, almost one hundred years passed before the extracapsular cataract extraction method finally replaced the old couching technique. By the middle of the 20th century, with the progression of the operation techniques and instruments, different forms of intracapsular cataract extraction methods became prevalent. Introduction and widespread use of the artificial intraocular lenses from the second half of the 20th century led to the rediscovery and further perfection of the extracapsular cataract extraction technique. Today, phacoemulsification through small incision, along with the foldable intraocular lenses is the gold standard of cataract surgery. The aim of this study is to present the different cataract surgery methods applied throughout the centuries, as well as the difficulties encountered. It discusses pioneering steps of each era, in order to give a closer look at the most frequently performed surgical intervention in ophthalmology. PMID:24184933

  7. Lens transglutaminase and cataract formation.

    OpenAIRE

    Lorand, L.; Hsu, L K; Siefring, G E; Rafferty, N S

    1981-01-01

    A protein polymer characteristically present in human cataract was shown to contain significant amounts of gamma-glutamyl-epsilon-lysine isopeptides. It is proposed that these crosslinks are produced by the action of transglutaminase (R-glutaminyl-peptide:amine-gamma-glutamyl-yltransferase, EC 2.3.2.13), which is all the more plausible because lens contains the enzyme and endogenous protein substrates for it. The enzyme is similar to that obtained from liver and is Ca2+ dependent. Highest app...

  8. Adrenomyeloneuropathy associated with congenital cataract

    International Nuclear Information System (INIS)

    Two cases of adrenomyeloneuropathy (AMN) in a family and the results of their MRI study are reported. Case 1, a 24-year-old male proband, was admitted to our hospital because of gait disturbance for three years. Bilateral cataracts were pointed out at birth, which required left side lenticotomy at age four. Neurological examinations on admission revealed a marked spastic paraparesis with pathological reflexes and a mild hypesthesia in the distal part of the left leg. No abnormal findings were detected in X-ray studies on the spine and spinal cord, electromyography and nerve conduction test. Serum very long chain fatty acids (VLCFAs) levels were apparently elevated, and the serum cortisol response to ACTH was low. Case 2, a 53-year-old woman, is the mother of Case 1 having a complaint of gait disturbance since age 51. She presented a mild spastic paraparesis with localized hypesthesia in the distal part of the both legs. She also had bilateral congenital cataracts. Her serum VLCFAs analysis indicated the intermediate levels between that of AMN and the normal control. Adrenal functions were normal. Cranial MRI (TR 2,000 msec/TE 80 msec) study disclosed high signal intensity areas in bilateral internal capsules in Case 1. These findings, suggesting the pathological change of dysmyelination, seemed to be well compatible with the clinical pictures. With these clinical findings and the laboratory data, these two cases were diagnosed as AMN. In addition, association of congenital cataract with AMN in both cases was characteristic in this family, which hasn't been reported in the literature. On regarding the genetic background of these two disorders, AMN and congenital cataract, it was speculated that each gene could be closely located on the same or very adjacent locus, possibly on Xq. (author)

  9. Visual acuity in unilateral cataract.

    OpenAIRE

    Thompson, D. A.; Møller, H; Russell-Eggitt, I.; Kriss, A

    1996-01-01

    BACKGROUND: Patching the fellow eye in infancy is a well recognised therapy to encourage visual development in the lensectomised eye in cases of unilateral congenital cataract. The possibility of iatrogenic deficits of the fellow eye was investigated by comparing the vision of these patients with untreated unilateral patients and binocularly normal controls. METHODS: Sweep visual evoked potentials (VEPs) offer a rapid and objective method for estimating grating acuity. Sweep VEPs were used to...

  10. Vitreous haemorrhage after cataract extraction.

    OpenAIRE

    Littlewood, K R; Constable, I J

    1985-01-01

    One hundred eyes undergoing intracapsular cataract extraction and 100 undergoing extracapsular extraction were examined prospectively within one week postoperatively and again at 6-10 weeks postoperatively. Indirect ophthalmoscopy showed vitreous haemorrhage in 36% of the intracapsular group and 13% of the extracapsular group. Vitreous haemorrhage was significantly related to the occurrence of operative hyphaema (p less than 0.01) but not to iridectomy (p greater than 0.05). In the intracapsu...

  11. Extracapsular cataract extraction - some problems.

    OpenAIRE

    Smith, R. J.; Doran, R.; Caswell, A

    1982-01-01

    Comments are made on the method of removing the anterior capsule during the performance of extracapsular cataract operations. The difficulty of performing this manoeuvre adequately is emphasised. Observations carried out during the postoperative period by means of the slit-lamp revealed some hitherto undescribed changes in the capsule. The edge of the anterior capsule can be clearly seen and looks like broken glass. Fine fibrils have been observed attached to the fractured capsular edge. In t...

  12. Craniofacial Microsomia: Goldenhar Syndrome in Association with Bilateral Congenital Cataract

    OpenAIRE

    Shrestha, U. D.; S. Adhikari

    2015-01-01

    Craniofacial microsomia (CFM) includes a spectrum of malformations primarily involving structures derived from the first and second branchial arches. Patients with hemifacial microsomia and epibulbar dermoids are said to have Goldenhar syndrome (GHS). Four-month-old boy with whitish pupillary reflex presented with the features of GHS in pediatric ophthalmology clinic. The child had ocular and auricular manifestations. There were no vertebral anomalies, but he had bilateral congenital cataract...

  13. Radioprotective effects of melatonin on radiation-induced cataract

    International Nuclear Information System (INIS)

    One of the mechanisms proposed to explain lens opacification is the oxidation of crystallins, either by radiation or reactive oxygen species (ROS). It has been shown that melatonin has both an anti-peroxidative effect on several tissues and a scavenger effect on ROS. The purpose of this study was to determine the antioxidant role of melatonin (5 mg/kg/day) against radiation-induced cataract in the lens after total-cranium irradiation of rats with a single dose of 5 Gy. Sprague-Dawley rats were divided into four groups. Control group received neither melatonin nor irradiation. Irradiated rats (IR) and melatonin+irradiated rats (IR+Mel) groups were exposed to total cranium irradiation of 5 Gy in a single dose by using a cobalt-60 teletherapy unit. IR+Mel and melatonin (Mel) groups were administered 5 mg/kg melatonin daily by intraperitoneal injections during ten days. Chylack's cataract classification was used in this study. At the end of the 10th day, the rats were killed and their eyes were enucleated to measure the antioxidant enzymes i.e. the activity of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px), and lipid peroxidation level (malondialdehyde (MDA)). Irradiation significantly increased the MDA level, as an end product of lipid peroxidation, and also significantly decreased SOD and GSH-Px activity, emphasizing the generation of increased oxidative stress. Rats injected with melatonin only did not cause cataract formation. Melatonin supplementation with irradiation significantly increased the activity of SOD and GSH-Px enzymes and significantly decreased the MDA level. Total cranium irradiation of 5 Gy in a single dose enhanced cataract formation, and melatonin supplementation protected the lenses from radiation-induced cataract formation. Our results suggest that supplementing cancer patients with adjuvant therapy of melatonin may reduce patients suffering from toxic therapeutic regimens such as chemotherapy and/or radiotherapy and may provide

  14. Persistent strabismus after cataract extraction

    Directory of Open Access Journals (Sweden)

    Dujić Mirjana P.

    2005-01-01

    Full Text Available Background. Transient ocular misalignment as a complication of parabulbar and peribulbar anesthesia has already been reported in the literature. The aim of our study was to present a case of irreversible iatrogenic vertical strabismus after cataract surgery, which had to be operated on. Methods. Clinical and orthoptic evaluation of a female patient with vertical diplopia after phacoemulsification cataract surgery. Results. One week after the uneventful surgery, a 68-year-old patient complained of a sudden vertical deviation in the operated eye. The patient had not had a history of previous motility disorders. On examination, the patient showed hypertropia in the left eye of 15−20 degrees in primary position. Three and 6 months postoperatively, there was no a spontaneous improvement, while the persistent vertical deviation was 40 prism dioptres. Strabismus surgery was required 1 year after the cataract surgery. Conclusion. Diplopia is a complication of peribulbar anesthesia which could be persistent. The superior and inferior rectus muscle are especially vulnerable. Its occurrence may be technique - related and the incidence increases when hyaluronidase is not available.

  15. Mechanisms involved in regulation of osteoclastic differentiation by mechanical stress-loaded osteoblasts

    International Nuclear Information System (INIS)

    Highlights: → Effect of compressive force on osteoblasts were examined. → Compressive force induced OPG expression and suppressed osteoclastogenesis. → This enhancement of OPG is dependent on Wnt/Ca2+ signal pathway. -- Abstract: Mechanical stress is known to be important for regulation of bone turnover, though the detailed mechanisms are not fully understood. In the present study, we examined the effect of mechanical stress on osteoblasts using a novel compression model. Mouse osteoblastic MC3T3-E1 cells were embedded in three-dimensional (3D) gels and cultured with continuous compressive force (0-10.0 g/cm2) for 48 h, and the conditioned medium were collected. RAW264.7 cells were then incubated with the conditioned medium for various times in the presence of receptor activator of nuclear factor-κB ligand (RANKL). Conditioned medium was found to inhibit the differentiation of RAW264.7 cells into osteoclasts induced by RANKL via down-regulation of the expression of tumor necrosis factor receptor-associated factor 6 (TRAF6), phosphorylation of IκBα, and nuclear translocation of p50 and p65. Interestingly, the conditioned medium also had a high level of binding activity to RANKL and blocked the binding of RANK to RANKL. Furthermore, the binding activity of conditioned medium to RANKL was reduced when the 3D gel was supplemented with KN-93, an inhibitor of non-canonical Wnt/Ca2+ pathway. In addition, expression level of osteoprotegerin (OPG) mRNA was increased in time- and force-dependent manners, and remarkably suppressed by KN-93. These results indicate that osteoblastic cells subjected to mechanical stress produce OPG, which binds to RANKL. Furthermore, this binding activity strongly inhibited osteoclastogenesis through suppression of TRAF6 and the nuclear factor-kappa B (NF-κB) signaling pathway, suggesting that enhancement of OPG expression induced by mechanical stress is dependent on non-canonical Wnt/Ca2+ pathway.

  16. Тhe shifts in the content of prostoglandins Е2 in aqueous humor of patients with senile and complicated cataracts

    OpenAIRE

    Zilfyan, A.A.

    2013-01-01

    Abstract Purpose. There has been undertaken in this research, in case of complicated cataracts, an attempt of definition of a role of prostaglandins Е2 (PgЕ2) in mechanisms of cancellation of immune responses, responsible for ACAID, in the early period of the aseptic uveitis course. Material and method. The patients with senile and complicated cataracts underwent the microaxial phonoemulsification. The first group included patients with senile uncomplicated cataract (400 eyes), the ...

  17. Association between metabolic syndrome and agerelated cataract

    Institute of Scientific and Technical Information of China (English)

    Sangshin; Park; Eun-Hee; Lee

    2015-01-01

    ·AIM: To determine the effect of metabolic syndrome on age-related cataract formation.·METHODS: We analyzed data for 2852 subjects [41.8%men and 58.2% women; mean(±SD) age, 52.9 ±13.9y],taken from the Korea National Health and Nutrition Examination Survey 2008. Metabolic syndrome was diagnosed by criteria proposed by the Joint Interim Societies. Cataract was diagnosed by using the Lens Opacities Classification System III. The association between metabolic syndrome and cataract was determined using age-adjusted and multivariable logistic regression analyses.· RESULTS: In multivariable analyses, men with metabolic syndrome had a 64% increased risk of nuclear cataract [odds ratio(OR), 1.64; 95% confidence interval(CI), 1.12-2.39]. Women with metabolic syndrome had a56% increased risk of cortical cataract(OR, 1.56; 95% CI,1.06-2.30). Men and women with metabolic syndrome had a 46%(OR, 1.46; 95% CI, 1.01-2.12) and 49%(OR,1.49; 95% CI, 1.07-2.08) increased risk of any cataract,respectively. The prevalence of nuclear and any cataract significantly increased with an increasing number of disturbed metabolic components in men, and prevalence of all types of cataracts increased in women. Men using hypoglycemic medication had an increased risk of nuclear(OR, 2.62; 95% CI, 1.41-4.86) and any(OR, 2.27;95% CI, 1.14-4.51) cataract, and women using antidyslipidemia medication had an increased risk of cortical(OR, 2.18; 95% CI, 1.12-4.24) and any(OR, 2.21;95% CI, 1.14-4.26) cataract.·CONCLUSION: Metabolic syndrome and its components,such as abdominal obesity, high blood pressure, andimpaired fasting glucose, are associated with age-related cataract formation in the Korean population.

  18. Pediatric cataract: challenges and future directions.

    Science.gov (United States)

    Medsinge, Anagha; Nischal, Ken K

    2015-01-01

    Cataract is a significant cause of visual disability in the pediatric population worldwide and can significantly impact the neurobiological development of a child. Early diagnosis and prompt surgical intervention is critical to prevent irreversible amblyopia. Thorough ocular evaluation, including the onset, duration, and morphology of a cataract, is essential to determine the timing for surgical intervention. Detailed assessment of the general health of the child, preferably in conjunction with a pediatrician, is helpful to rule out any associated systemic condition. Although pediatric cataracts have a diverse etiology, with the majority being idiopathic, genetic counseling and molecular testing should be undertaken with the help of a genetic counselor and/or geneticist in cases of hereditary cataracts. Advancement in surgical techniques and methods of optical rehabilitation has substantially improved the functional and anatomic outcomes of pediatric cataract surgeries in recent years. However, the phenomenon of refractive growth and the process of emmetropization have continued to puzzle pediatric ophthalmologists and highlight the need for future prospective studies. Posterior capsule opacification and secondary glaucoma are still the major postoperative complications necessitating long-term surveillance in children undergoing cataract surgery early in life. Successful management of pediatric cataracts depends on individualized care and experienced teamwork. We reviewed the etiology, preoperative evaluation including biometry, choice of intraocular lens, surgical techniques, and recent developments in the field of childhood cataract. PMID:25609909

  19. Lutein and cataract: from bench to bedside.

    Science.gov (United States)

    Manayi, Azadeh; Abdollahi, Mohammad; Raman, Thiagarajan; Nabavi, Seyed Fazel; Habtemariam, Solomon; Daglia, Maria; Nabavi, Seyed Mohammad

    2016-10-01

    Cataract is one of the most important leading causes of blindness in the world. Extensive research showed that oxidative stress may play an important role in the initiation and progression of a cataract and other age-related eye diseases. Extra-generation of reactive oxygen and nitrogen species in the eye tissue has been shown as one of the most important risk factors for cataracts and other age-related eye diseases. With respect to this, it can be hypothesized that dietary antioxidants may be useful in the prevention and/or mitigation of cataract. Lutein is an important xanthophyll which is widely found in different vegetables such as spinach, kale and carrots as well as some other foods such as eggs. Lutein is concentrated in the macula and suppresses the oxidative stress in the eye tissues. A plethora of literature has shown that increased lutein consumption has a close correlation with reduction in the incidence of cataract. Despite this general information, there is a negligible number of review articles considering the beneficial effects of lutein on cataracts and age-related eye diseases. The present review is aimed at discussing the role of oxidative stress in the initiation and progression of a cataract and the possible beneficial effects of lutein in maintaining retinal health and fighting cataract. We also provide a perspective on the chemistry, sources, bioavailability and safety of lutein. PMID:26042352

  20. CRISPR/Cas9-mediated GJA8 knockout in rabbits recapitulates human congenital cataracts.

    Science.gov (United States)

    Yuan, Lin; Sui, Tingting; Chen, Mao; Deng, Jichao; Huang, Yongye; Zeng, Jian; Lv, Qingyan; Song, Yuning; Li, Zhanjun; Lai, Liangxue

    2016-01-01

    Cataracts are the leading cause of vision loss in the world, although surgical treatment can restore vision in cataract patients. Until now, there have been no adequate animal models for in vivo studies of artificial lens safety and drug interactions. Genetic studies have demonstrated that GJA8 is involved in maintaining lens opacity and proper lens development. In this study, a cataract model with GJA8 gene knockout was developed via co-injection of Cas9/sgRNA mRNA into rabbit zygotes. Our results showed that gene mutation efficiency in the GJA8 locus reached 98.7% in embryos and 100% in pups, demonstrating that the Cas9/sgRNA system is a highly efficient tool for gene editing in rabbits. In agreement with other studies, our genetic and histology results showed that impaired GJA8 function caused microphthalmia, small lens size and cataracts. In summary, our novel rabbit model of cataracts will be an important drug-screening tool for cataract prevention and treatment. PMID:26912477

  1. CRISPR/Cas9-mediated GJA8 knockout in rabbits recapitulates human congenital cataracts

    Science.gov (United States)

    Yuan, Lin; Sui, Tingting; Chen, Mao; Deng, Jichao; Huang, Yongye; Zeng, Jian; Lv, Qingyan; Song, Yuning; Li, Zhanjun; Lai, Liangxue

    2016-01-01

    Cataracts are the leading cause of vision loss in the world, although surgical treatment can restore vision in cataract patients. Until now, there have been no adequate animal models for in vivo studies of artificial lens safety and drug interactions. Genetic studies have demonstrated that GJA8 is involved in maintaining lens opacity and proper lens development. In this study, a cataract model with GJA8 gene knockout was developed via co-injection of Cas9/sgRNA mRNA into rabbit zygotes. Our results showed that gene mutation efficiency in the GJA8 locus reached 98.7% in embryos and 100% in pups, demonstrating that the Cas9/sgRNA system is a highly efficient tool for gene editing in rabbits. In agreement with other studies, our genetic and histology results showed that impaired GJA8 function caused microphthalmia, small lens size and cataracts. In summary, our novel rabbit model of cataracts will be an important drug-screening tool for cataract prevention and treatment. PMID:26912477

  2. Use of static lung mechanics to identify early pulmonary involvement in patients with ankylosing spondylitis.

    OpenAIRE

    Aggarwal A; Gupta D; Wanchu A; Jindal S

    2001-01-01

    AIM: To assess if a detailed analysis of lung mechanics could help in early recognition of pulmonary abnormalities in patients with ankylosing spondylitis. METHODS: Static pulmonary mechanics were studied in 17 patients (16 men and one woman) of ankylosing spondylitis with no obvious clinical or radiological evidence of pulmonary involvement. Lung pressure-volume relationship was generated using a whole body plethysmograph, and a monoexponential equation fitted to this data. RESULTS: Total lu...

  3. Aspiration of radiation cataract in children of retinoblastoma

    International Nuclear Information System (INIS)

    We operated on the radiation cataracts of 12 retinoblastoma patients who had been treated by conservative therapeutic means including radiation, cryoapplication, photocoagulation, and cytostatic agents. Before the surgery, we checked that the tumor had disappeared or scarred by means of CT-scan, Ultrasonography, X-ray, and so on. Visual acuity of 1.0 or more was retained in two eyes (17 %). Four eyes (33 %) retained visual acuity of 0.6-0.4, one eye (8 %) retained 0.1 and the remaining five eyes (42 %) had visual acuity of less than 0.1. We experienced no serious complications during or after the surgeries. The reason for poorer visual acuity was either macular involvement of the tumor or radiation retinopathy due to larger dosis of radiation. Therefore, we conclude that aspiration of radiation cataract is an effective treatment of retinoblastoma patients after the tumor has disappeared or scarred. (author)

  4. Cataract surgery after Descemet stripping endothelial keratoplasty

    Directory of Open Access Journals (Sweden)

    Sunita Chaurasia

    2012-01-01

    Full Text Available Management of endothelial dysfunction in phakic patients is sometimes a dilemma for corneal surgeons. Phakic patients with visually significant cataract and endothelial dysfunction are preferably managed by performing combined cataract surgery with endothelial keratoplasty. However, combined surgery may be deferred in eyes with early incipient cataract, younger age and where anterior chamber is poorly visualized. As cataract formation may be accelerated after endothelial keratoplasty, these eyes may need cataract surgery subsequently. Surgical intervention in eyes with endothelial keratoplasty is of concern as this may affect the graft adversely and threaten graft survival. In this report, we describe the intraoperative surgical details and postoperative clinical course of a patient who underwent phacoemulsification with intraocular lens implantation after Descemet stripping automated endothelial keratoplasty (DSAEK.

  5. Surgical consequences in coexisting cataract and glaucoma.

    Science.gov (United States)

    Blumenthal, M; Glovinsky, Y

    1995-04-01

    Of the three classical approaches to surgery for coexisting cataract and glaucoma, last year's publications dealt with the surgical consequences of combined cataract and glaucoma operations only. When used in combined cataract and glaucoma surgery, a small-incision extracapsular cataract extraction (ECCE) with phacoemulsification (PHACO) was found to be only slightly superior to the standard manual ECCE in terms of postoperative intraocular pressure (IOP) control. Injections of 5-fluorouracil postoperatively did not improve IOP control in PHACO-ECCE-trabeculectomy or manual ECCE-trabeculectomy. A preliminary uncontrolled report suggests, however, that intraoperative mitomycin C application in PHACO-ECCE-trabeculectomy may result in excellent postoperative IOP control without antiglaucomatous medications, and with no significant mitomycin C-related complications. Controlled studies on mitomycin C application in small-incision cataract and glaucoma surgery are needed to assess its long-term effect on IOP and astigmatism. PMID:10150852

  6. Pediatric cataract: challenges and future directions

    Directory of Open Access Journals (Sweden)

    Medsinge A

    2015-01-01

    Full Text Available Anagha Medsinge,1,2 Ken K Nischal1,2 1Pediatric Ophthalmology, Strabismus, and Adult Motility, Children’s Hospital of Pittsburgh of University of Pittsburgh Medical Center, (UPMC 2University of Pittsburgh School of Medicine, Pittsburgh, PA, USA Abstract: Cataract is a significant cause of visual disability in the pediatric population worldwide and can significantly impact the neurobiological development of a child. Early diagnosis and prompt surgical intervention is critical to prevent irreversible amblyopia. Thorough ocular evaluation, including the onset, duration, and morphology of a cataract, is essential to determine the timing for surgical intervention. Detailed assessment of the general health of the child, preferably in conjunction with a pediatrician, is helpful to rule out any associated systemic condition. Although pediatric cataracts have a diverse etiology, with the majority being idiopathic, genetic counseling and molecular testing should be undertaken with the help of a genetic counselor and/or geneticist in cases of hereditary cataracts. Advancement in surgical techniques and methods of optical rehabilitation has substantially improved the functional and anatomic outcomes of pediatric cataract surgeries in recent years. However, the phenomenon of refractive growth and the process of emmetropization have continued to puzzle pediatric ophthalmologists and highlight the need for future prospective studies. Posterior capsule opacification and secondary glaucoma are still the major postoperative complications necessitating long-term surveillance in children undergoing cataract surgery early in life. Successful management of pediatric cataracts depends on individualized care and experienced teamwork. We reviewed the etiology, preoperative evaluation including biometry, choice of intraocular lens, surgical techniques, and recent developments in the field of childhood cataract. Keywords: children, pediatric cataract, infantile

  7. Cataract research using electronic health records

    Directory of Open Access Journals (Sweden)

    Waudby Carol J

    2011-11-01

    Full Text Available Abstract Background The eMERGE (electronic MEdical Records and Genomics network, funded by the National Human Genome Research Institute, is a national consortium formed to develop, disseminate, and apply approaches to research that combine DNA biorepositories with electronic health record (EHR systems for large-scale, high-throughput genetic research. Marshfield Clinic is one of five sites in the eMERGE network and primarily studied: 1 age-related cataract and 2 HDL-cholesterol levels. The purpose of this paper is to describe the approach to electronic evaluation of the epidemiology of cataract using the EHR for a large biobank and to assess previously identified epidemiologic risk factors in cases identified by electronic algorithms. Methods Electronic algorithms were used to select individuals with cataracts in the Personalized Medicine Research Project database. These were analyzed for cataract prevalence, age at cataract, and previously identified risk factors. Results Cataract diagnoses and surgeries, though not type of cataract, were successfully identified using electronic algorithms. Age specific prevalence of both cataract (22% compared to 17.2% and cataract surgery (11% compared to 5.1% were higher when compared to the Eye Diseases Prevalence Research Group. The risk factors of age, gender, diabetes, and steroid use were confirmed. Conclusions Using electronic health records can be a viable and efficient tool to identify cataracts for research. However, using retrospective data from this source can be confounded by historical limits on data availability, differences in the utilization of healthcare, and changes in exposures over time.

  8. The scientific basis of a threshold dose for radiation cataract and its underlying issues

    International Nuclear Information System (INIS)

    Radiation cataract has been classified as tissue reactions (formerly known as deterministic effects or non-stochastic effects) with a threshold dose. In 1984, the International Commission on Radiological Protection (ICRP) suggested the threshold dose of >8 Sv for vision-impairing cataracts in highly fractionated or protracted exposures. Such a threshold was used to recommend an occupational dose limit for the lens of 150 mSv/year in 1990 and 2007, but was reduced to 0.5 Sv in 2011 for all exposure scenarios irrespective of the rate of dose delivery. New threshold was determined on the basis of the limited human evidence, with various hypotheses not supported by the present knowledge of biological mechanisms. Examples of untested hypotheses include: radiation cataract is a tissue reaction; radiation damage to the large number of cells acts as a triggering event for radiation cataract; detectable minor opacities progress into vision-impairing cataracts with time; and the lower the dose, the longer the latency. This paper discusses the issues behind the scientific basis for the new threshold, and provides directions for future epidemiological and biological studies to establish the reasonably modeled dose-response relationship for radiation cataract. (author)

  9. On reaction mechanisms involved in the deuteron–induced surrogate reactions

    International Nuclear Information System (INIS)

    An extended analysis of the nuclear reaction mechanisms involved within deuteron interaction with nuclei, namely the breakup, stripping, pick-up, pre-equilibrium emission, and evaporation from fully equilibrated compound nucleus, is presented in order to highlight the importance of the direct mechanisms still neglected in the analysis of deuteron-induced surrogate reactions. Particularly, the dominance of the breakup mechanism at low energies around the Coulomb barrier should be considered in the case of (d,x) surrogate reactions on actinide target nuclei

  10. On reaction mechanisms involved in the deuteron–induced surrogate reactions

    Energy Technology Data Exchange (ETDEWEB)

    Avrigeanu, M.; Avrigeanu, V.; Mănăilescu, C. [Horia Hulubei National Institute for Physics and Nuclear Engineering, P.O. Box MG-6, 077125 Bucharest-Magurele (Romania)

    2015-02-24

    An extended analysis of the nuclear reaction mechanisms involved within deuteron interaction with nuclei, namely the breakup, stripping, pick-up, pre-equilibrium emission, and evaporation from fully equilibrated compound nucleus, is presented in order to highlight the importance of the direct mechanisms still neglected in the analysis of deuteron-induced surrogate reactions. Particularly, the dominance of the breakup mechanism at low energies around the Coulomb barrier should be considered in the case of (d,x) surrogate reactions on actinide target nuclei.

  11. A theoretical study of the molecular mechanism of the GAPDH Trypanosoma cruzi enzyme involving iodoacetate inhibitor

    Science.gov (United States)

    Carneiro, Agnaldo Silva; Lameira, Jerônimo; Alves, Cláudio Nahum

    2011-10-01

    The glyceraldehyde-3-phosphate dehydrogenase enzyme (GAPDH) is an important biological target for the development of new chemotherapeutic agents against Chagas disease. In this Letter, the inhibition mechanism of GAPDH involving iodoacetate (IAA) inhibitor was studied using the hybrid quantum mechanical/molecular mechanical (QM/MM) approach and molecular dynamic simulations. Analysis of the potential energy surface and potential of mean force show that the covalent attachment of IAA inhibitor to the active site of the enzyme occurs as a concerted process. In addition, the energy terms decomposition shows that NAD+ plays an important role in stabilization of the reagents and transition state.

  12. Results of cataract surgery in the very elderly population

    Directory of Open Access Journals (Sweden)

    Michalska-Małecka K

    2013-08-01

    Full Text Available Katarzyna Michalska-Małecka,1 Mariusz Nowak,2 Piotr Gościniewicz,1 Jacek Karpe,3 Ludmiła Słowińska-Łożyńska,4 Agnieszka Łypaczewska,1 Dorota Romaniuk11Department of Ophthalmology, University Hospital No 5, Medical University of Silesia, Katowice, 2Pathophysiology Division, Department of Pathophysiology and Endocrinology, Medical University of Silesia, Zabrze, 3Department of Anesthesiology and Intensive Therapy, Medical University of Silesia, Zabrze, 4Department of Biophysics, Faculty of Medicine in Zabrze, Medical University of Silesia, Katowice, Silesia, PolandAim: The aim of our study was to retrospectively evaluate the effectiveness and safety of cataract surgery and intraocular lens implantation (IOL for patients aged 90 years or older, whom we define as “very elderly.”Methods: The study involved a total number of 122 patients (122 eyes with senile cataracts. The mean age of patients was 91.2 ± 2.3 years (range 90–100 years old. Phacoemulsification (phaco was done on 113 of 122 eyes, and 9 of 122 eyes had extracapsular cataract extraction (ECCE. Postoperative visual acuity and intraocular pressure (IOP were analyzed on the first postoperative day, 3 months after surgery, and 6 months after surgery.Results: Best corrected visual acuity (BCVA improved in 100 of 122 eyes (82.0%. BCVA remained the same in 20 of 122 eyes (16.4% and decreased in 2 of 122 eyes (1.6%, mainly because of coexisting age-related macular degeneration (AMD. The BCVA 3 months after surgery was ≥0.8 in 23 of 122 eyes (18.9%, between 0.5 and 0.7 in 28 of 122 eyes (22.3%, and between 0.2 and 0.4 in 33 of 122 eyes (27.1%. We found significant implications of cataract surgery on decreasing IOP in the studied group of patients suffering from glaucoma compared to the patients without glaucoma.Conclusion: Advanced age is not a contraindication for cataract surgery. The results of the study showed that when systemic conditions are stable, both phaco and ECCE with

  13. Relationship between cataracts and epilation in atomic bomb survivors

    International Nuclear Information System (INIS)

    Among 1713 atomic bomb survivors who underwent ophthalmological examinations from 1963-1964, the risk of cataract formation per unit dose of radiation was significantly greater for those who reported hair loss of 67% or more after exposure (the epilation group) than for those who reported less or no hair loss (the no-epilation group) (P,0.01). Such an epilation effect has also been associated with leukemia mortality and the frequency of chromosome aberrations. Although this might be interpreted as indicating differential sensitivity to radiation between the epilation group and the no-epilation group, it could also be explained by imprecision in dose estimates. We have calculated that a 48% random error in DS86 dose estimates could be in accordance with the dose-response relationship for the prevalence of cataracts in the epilation group or the no-epilation group. Possible mechanisms for variations in radiosensitivity are discussed. 37 refs., 2 figs., 4 tabs

  14. Human βA3/A1-crystallin splicing mutation causes cataracts by activating the unfolded protein response and inducing apoptosis in differentiating lens fiber cells.

    Science.gov (United States)

    Ma, Zhiwei; Yao, Wenliang; Chan, Chi-Chao; Kannabiran, Chitra; Wawrousek, Eric; Hejtmancik, J Fielding

    2016-06-01

    βγ-Crystallins, having a uniquely stable two domain four Greek key structure, are crucial for transparency of the eye lens,. Mutations in lens crystallins have been proposed to cause cataract formation by a variety of mechanisms most of which involve destabilization of the protein fold. The underlying molecular mechanism for autosomal dominant zonular cataracts with sutural opacities in an Indian family caused by a c.215+1G>A splice mutation in the βA3/A1-crystallin gene CRYBA1 was elucidated using three transgenic mice models. This mutation causes a splice defect in which the mutant mRNA escapes nonsense mediated decay by skipping both exons 3 and 4. Skipping these exons results in an in-frame deletion of the mRNA and synthesis of an unstable p.Ile33_Ala119del mutant βA3/A1-crystallin protein. Transgenic expression of mutant βA3/A1-crystallin but not the wild type protein results in toxicity and abnormalities in the maturation and orientation of differentiating lens fibers in c.97_357del CRYBA1 transgenic mice, leading to a small spherical lens, cataract, and often lens capsule rupture. On a cellular level, the lenses accumulated p.Ile33_Ala119del βA3/A1-crystallin with resultant activation of the stress signaling pathway - unfolded protein response (UPR) and inhibition of normal protein synthesis, culminating in apoptosis. This highlights the mechanistic contrast between mild mutations that destabilize crystallins and other proteins, resulting in their being bound by the α-crystallins that buffer lens cells against damage by denatured proteins, and severely misfolded proteins that are not bound by α-crystallin but accumulate and have a direct toxic effect on lens cells, resulting in early onset cataracts. PMID:26851658

  15. CORNEAL ASTIGMATISM AFTER MANUAL SMALL INCISION CATARACT SURGERY

    OpenAIRE

    Rajni; Mohd Ayaz; Pallvi; Syed Tariq

    2014-01-01

    INTRODUCTION: Cataract is the leading cause of preventable blindness in India. Manual Small Incision Cataract Surgery is still the preferred method of cataract surgery because of its low cost and non-dependence on costly equipments. Postoperatively astigmatism is an important cause of poor uncorrected visual acuity after cataract surgery. Purpose: The purpose of this study was to assess corneal astigmatism in manual small incision cataract surgery in superior versus temporal ...

  16. Bimanual microincisional cataract surgery technique and clinical outcome

    OpenAIRE

    Al-Muammar, Abdulrahman

    2009-01-01

    Bimanual microincisional cataract surgery has been introduced recently as a technique for cataract surgery and it is gaining interest of many cataract surgeons in the world. Over the last few years many changes were made in the phacoemulsification machines and the intraocular lenses design which allowed bimanual microincisional cataract surgery to be safer and more efficient. The purpose of this review is to introduce the technique of bimanual microincisional cataract surgery and to review al...

  17. Cataract incidence after total-body irradiation

    International Nuclear Information System (INIS)

    Purpose: The aim of this retrospective study was to evaluate cataract incidence in a homogeneously-treated group of patients after total-body irradiation (TBI) followed by autologous bone marrow transplantation or peripheral blood stem cell transplantation. Methods and Materials: Between 1982 and 1994, a total of 260 patients received either autologous bone marrow or blood stem cell transplantation for hematological malignancy at the University of Heidelberg. Two hundred nine of these patients received TBI in our hospital. Radiotherapy was applied as hyperfractionated TBI, with a median dose of 14.4 Gy in 12 fractions over 4 days. Minimum time between fractions was 4 h. Photons with an energy of 23 MeV were used with a dose rate of 7-18 cGy/min. Ninety-six of the 209 irradiated patients were still alive in 1996; 86 of these patients (52 men, 33 women) answered a questionnaire and could be examined ophthalmologically. The median age at time of TBI was 38.5 years, with a range of 15-59 years. Results: The median follow-up is now 5.8 years, with a range of 1.7-13 years. Cataract occurred in 28/85 patients (32.9%) after a median of 47 months (1-104 months). In 6 of 28 patients who developed a cataract, surgery of the cataract was performed. Whole-brain irradiation prior to TBI had been performed more often in the group of patients developing cataract (14.3%) versus 10.7% in the group of patients without cataract. However, there was no statistical difference (Chi-square, p > 0.05). Conclusion: Cataract is a common side effect of TBI. Cataract incidence found in our patients is comparable to results of other centers using a fractionated regimen for TBI. To assess the incidence of cataract after TBI, a long-term follow-up is required

  18. Manual Suture Less Small Incision Cataract Surgery in Patients with Uveitic Cataract

    OpenAIRE

    Rahul Bhargava; Prachi Kumar; Hafsa Bashir; Shiv Kumar Sharma; Anurag Mishra

    2014-01-01

    Purpose: The purpose of this study is to evaluate the outcome of manual small incision cataract surgery (SICS) in eyes with uveitic cataract. Setting: Medical college hospital of the subcontinent. Design: Retrospective case series. Materials and Methods: In this retrospective study, patients who underwent SICS with posterior chamber intraocular lens implantation for uveitic cataract from 2006 to 2009 were evaluated. Patients with less than 3 months follow-up were excluded. Post-opera...

  19. Visual outcome following extracapsular cataract extraction in mature cataracts with pseudoexfoliation syndrome: A retrospective study

    OpenAIRE

    Abdullah Al-Mujaini; Wali, Upender K.

    2013-01-01

    Purpose/Objective: To report the best corrected visual acuity, at the end of one year, in 33 patients (35 eyes), who underwent extracapsular cataract extraction (ECCE) with posterior chamber intraocular lens implantation (PC-IOL) for mature and hypermature cataracts, with pseudoexfoliation (PEX). Design: Retrospective, non-comparative, single-institutional (Sultan Qaboos University Hospital) study. Participants: Thirty-three patients with mature and hypermature cataracts, with PEX opera...

  20. Socioeconomic barriers to cataract surgery in Nepal: the south Asian cataract management study

    OpenAIRE

    Snellingen, T; Shrestha, B.; Gharti, M; Shrestha, J.; Upadhyay, M; Pokhrel, R

    1998-01-01

    BACKGROUND—Previous studies have shown that, despite an increasing availability of cataract surgery, important socioeconomic barriers exist in the acceptance of surgery in many rural areas of south Asia. Nepal has developed a comprehensive national network of eye hospitals but the surgical coverage for the treatment of cataract blind is still low.
AIMS—To determine the utilisation of cataract surgery and the level of physical and psychosocial impairment and the socioeconomic barriers to surge...

  1. Sutureless Cataract Surgery: Principles and Steps

    Directory of Open Access Journals (Sweden)

    John Sandford-Smith

    2003-01-01

    Full Text Available Introduction. Cataracts cause about 50% of world blindness. There is little likelihood of effective prevention becoming available in the next few years and so the only treatment will remain surgical. For many of the other major causes of world blindness, like trachoma, xerophthalmia and onchocerciasis, the remedy is community-based, not hospital-based, and requires prevention rather than treatment. The prevalence of blinding cataract will only increase as people live longer, so cataract will continue to be, by far, the most important treatable cause of blindness.

  2. An X-ray vision of cataract

    CERN Document Server

    Antunes, A; Barros, P S M; Morelhao, S L; Antunes, Andrea; Safatle, Angelica M.V.; Barros, Paulo S.M.; Morelhao, Sergio L.

    2005-01-01

    This work reports the exploitation of diffraction enhanced X-ray imaging (DEI) for studying cataract in addition to the finding of heavy scattering centers of light, probably Ca-rich precipitates in cataractous lenses. DEI selectively probes diffuse-scattering, refraction, and absorption properties of features in the lenses. Fiber cell compaction areas and dilute distribution of precipitates are identifiable, as well as highly absorbing aggregations providing contrast even in the conventional radiography setup. This finding opens new opportunities for clinical diagnosis, for understaning the causes of cataract, and in developing medicines for this disease.

  3. Physical mechanisms involved in grooved flat heat pipes: experimental and numerical analyses

    OpenAIRE

    Lips, S.; Lefevre, F.; Bonjour, J.

    2011-01-01

    An experimental database, obtained with flat plate heat pipes (FPHP) with longitudinal grooves is presented. The capillary pressure measured by confocal microscopy and the temperature field in the wall are presented in various experimental conditions (vapour space thickness, filing ratio, heat transfer rate, tilt angle, fluid). Coupled hydrodynamic and thermal models are developed. Experimental results are compared to results of numerical models. Physical mechanisms involved in grooved heat p...

  4. Glaucoma after Congenital Cataract Surgery

    Directory of Open Access Journals (Sweden)

    Mahmoodreza Panahi Bazaz

    2014-05-01

    Full Text Available Purpose: To determine the incidence and risk factors associated with glaucoma following congenital cataract surgery (CCS in children under age of 15 Methods: This prospective cohort (since 2006 consisted of children less than 15 years of age who underwent cataract surgery with or without intraocular lens (IOL implantation. The role of the following factors on the development of glaucoma after CCS including age at surgery, gender, laterality of the cataract, IOL implantation, congenital ocular anomalies, intra- and postoperative complications, length of follow-up, central corneal thickness (CCT as well as the effect of the age of onset, time to development of glaucoma, and response to treatment were evaluated. Results: Overall, 161 eyes of 96 patients were included in this study of which 28 eyes developed glaucoma. Incidence of glaucoma was 17.4%. Mean±SD age at surgery was 9.3±6.9 (range, 1-24 months in glaucomatous and 40.4±41.1 (range, 1 m-13.6 year months in non-glaucomatous group (p<0.001. All glaucoma patients had the operation under two years of age. In group 1, 9 (60% and in group 2, 24 (30% patients were female (p=0.001. In group 1, 17 eyes (60.7% and in the group 2, 41 eyes (30.8% were aphakic (p=0.001. Mean time to diagnosis of glaucoma was 111.2 days (range 30-1200 days. Mean follow-up time was 3.1 years (range, 1-6 years. In 22 (78.6% eyes glaucoma was diagnosed within six months after surgery. Glaucoma was controlled with medications in 23 eyes (82% and with surgery in five eyes. Conclusion: In this study the incidence of glaucoma after CCS was 17.4% over a follow-up period of six years. Younger age at the time of lensectomy increases the risk of secondary glaucoma. IOL implantation may protect against glaucoma. Female gender was affected more than male.

  5. Use of static lung mechanics to identify early pulmonary involvement in patients with ankylosing spondylitis.

    Directory of Open Access Journals (Sweden)

    Aggarwal A

    2001-04-01

    Full Text Available AIM: To assess if a detailed analysis of lung mechanics could help in early recognition of pulmonary abnormalities in patients with ankylosing spondylitis. METHODS: Static pulmonary mechanics were studied in 17 patients (16 men and one woman of ankylosing spondylitis with no obvious clinical or radiological evidence of pulmonary involvement. Lung pressure-volume relationship was generated using a whole body plethysmograph, and a monoexponential equation fitted to this data. RESULTS: Total lung capacity (TLC was reduced in one (5.9% and static lung compliance (Cst in nine (52.9% patients. Four (23.5% patients had normal TLC, yet Cst and shape constant (K were reduced. Five (29.4% patients had reduced TLC and Cst; four of them had low K. One (5.9% patient had normal TLC but elevated Cst and K. CONCLUSIONS: Pulmonary involvement in patients with ankylosing spondylitis is probably diffuse and begins much earlier than generally presumed. Evaluation of static lung mechanics can identify pulmonary involvement early in the course of disease in several of these patients.

  6. Relationship of cataract to radiation sensitivity

    International Nuclear Information System (INIS)

    This investigation was conducted to ascertain whether cellular hypersensitivity to radiation may be identified as a possible cause of cataract in persons exposed to low levels of radiation. Patients were studied in whom posterior subcapsular cataract (PSC) had followed probable exposure to low levels of radiation or in whom PSC had developed before the age of 60 without known exposure. Patients with cataract were compared with age and sex matched controls. Radiation sensitivity was estimated by measuring clonal growth of skin fibroblasts and peripheral blood lymphocytes after exposure to graded doses of radiation and by measuring postirradiation reconstruction of separated nuclear material from lymphocytes. Results show variations in radiation sensitivity between patients, without significant differences from the controls. It is concluded that radiation hypersensitivity is not normally associated with development of posterior subcapsular cataract. (author)

  7. Evaluation of Cataract Preventive Action of Phycocyanin

    Directory of Open Access Journals (Sweden)

    Kothadia AD

    2011-01-01

    Full Text Available Phycocyanin is a biliprotein pigment found in blue-green algae Spirulina platensis, which have attracted attention because of their nutritional value and medicinal properties. This pigment has antioxidant, anti-inflammatory and hepatoprotective activity in different experimental models. This data supports the view that phycocyanin may prevent cataract progression. Cataract preventive action of phycocyanin was evaluated against naphthalene and galactose induced cataract experimental models in wistar rats at dose 200 mg/kg/day p.o and vitamin E was used as a reference standard. Phycocyanin treated animals showed no opacification in the lens and they also showed significantly increased level of glutathione (GSH, soluble proteins and water content as compared to positive control group in the lens in both the experimental models. Cataract preventive action of phycocyanin may be due to is antioxidant and free radical scavenging activity.

  8. [The surgical results in traumatic cataract].

    Science.gov (United States)

    Chiseliţă, D; Vancea, P P; Filimon, O; Brănişteanu, D; Bredetean, M; Poiata, I

    1995-01-01

    The retrospective analysis of the postoperative course in 204 traumatic cataracts (140 isolated, simple cataracts and 64 aggravated ones) showed an apparent functional improvement in the simple cases (preoperative and postoperative visual acuity 0.0139 and 0.8520, respectively); the incidence of postoperative detachment of retina was of 4.9%, that of postoperative endophthalmitis that of cystoid macular edema of 3.2%; complications more commonly occurred in aggravated traumatic cataracts and partially accounted for the poorer functional results. During the investigated interval (1988-1992) a rapid shift to extracapsular cataract extraction and posterior chamber lens implants was made. The crystalline grafts preserved binocular vision in 92% of the cases and contact lens in 50% of the cases. Lens implant remains a matchless solution for the visual rehabilitation of the patients with aphakia. PMID:7654673

  9. Intraocular lens employed for cataract surgery

    Science.gov (United States)

    Roszkowska, A. M.; Torrisi, L.

    2014-04-01

    The aim of this paper is to illustrate the techniques of cataract surgery with implantation of intraocular lenses and some physical properties of the used materials. The new technology, coupled with extensive experience and the studied cases, permits to increase the standardization and accuracy of the engravings, by reducing the use and handling of surgical instruments inside the eye. At present it is possible to replace the cataract with crystalline lenses based on biopolymers such as PMMA, silicone, acrylic hydrophilic and hydrophobic acrylic. These materials are increasingly able to replace the natural lens and to ensure the fully functional of the eye. The role of femtosecond lasers in cataract surgery, to assist or replace several aspects of the manual cataract surgery, are discussed.

  10. Broken intraocular lens during cataract surgery.

    OpenAIRE

    Kirkpatrick, J N; Cook, S D

    1992-01-01

    A case of planned routine extracapsular cataract extraction is described where surgery was complicated peroperatively by fracture of the posterior chamber lens implant. The technique of lens implantation is discussed.

  11. Intraocular lens employed for cataract surgery

    International Nuclear Information System (INIS)

    The aim of this paper is to illustrate the techniques of cataract surgery with implantation of intraocular lenses and some physical properties of the used materials. The new technology, coupled with extensive experience and the studied cases, permits to increase the standardization and accuracy of the engravings, by reducing the use and handling of surgical instruments inside the eye. At present it is possible to replace the cataract with crystalline lenses based on biopolymers such as PMMA, silicone, acrylic hydrophilic and hydrophobic acrylic. These materials are increasingly able to replace the natural lens and to ensure the fully functional of the eye. The role of femtosecond lasers in cataract surgery, to assist or replace several aspects of the manual cataract surgery, are discussed.

  12. Lens and cataract research of the 20th century: a review of results, errors and misunderstandings.

    Science.gov (United States)

    Hockwin, Otto; Kojima, Masami; Müller-Breitenkamp, Ursula; Wegener, Alfred

    2002-01-01

    Lens and cataract research from a clinical, biophysical, biological and mainly biochemical point of view has a long tradition. Already since the beginning of the 20th century research relating to the chemical composition and metabolism of the lens was conducted. With these analyses an attempt was made to understand the existence and maintenance of lens transparency and the mechanisms leading to lens opacities. Around the middle of the century the stationary analyses measuring the content of certain substances in the lens were more and more replaced by the search for dynamic metabolic processes responsible for lens growth, maintenance of transparency and possibly active participation in lens function (such as accommodation). Also the disturbances as a result of ageing or the formation of lens opacities have been investigated and resulted partially in the elucidation of reaction chains, leading from a trigger to the formation of a cataract. Lens biochemistry is no longer a closed book to us, but there are still many question marks. Why were we not able to solve more problems around lens and cataract? The research effort with a remarkable financial input and a great number of scientists worldwide during the second half of the century does not correspond to the results obtained. There must be something wrong with our strategy, our interpretation of the results or even both. We would like to stress some points which might be regarded as errors or misunderstandings in the lens research community, thus preventing a better outcome of the enormous investment of work and money. A great disadvantage is the missing cooperation between clinicians and epidemiologists on one hand and basic lens researchers on the other. Especially the ignorance of basic researchers regarding the clinical problems of the lens and of cataracts might be to blame for several 'errors and misunderstandings'. It is not even so long ago since the slitlamp microscope examination of animals belonged to the

  13. Cataracts

    Science.gov (United States)

    ... Uveitis Focus On Pediatric Ophthalmology Education Center Oculofacial Plastic Surgery Center Laser Surgery Education Center Redmond Ethics Center ... Uveitis Focus On Pediatric Ophthalmology Education Center Oculofacial Plastic Surgery Center Laser Surgery Education Center Redmond Ethics Center ...

  14. Cataract - Multiple Languages: MedlinePlus

    Science.gov (United States)

    ... Chinese - Simplified (简体中文) Chinese - Traditional (繁體中文) French (français) Hindi (हिन्दी) Japanese (日本語) Korean (한국어) Portuguese (português) ... Cataracte - français (French) Bilingual PDF Health Information Translations Hindi (हिन्दी) Cataract हिन्दी (Hindi) Bilingual PDF ...

  15. Childhood cataract in sub-Saharan Africa

    OpenAIRE

    Courtright, Paul

    2011-01-01

    Investment by organizations and agencies has led to a growing body of evidence and information to assist ophthalmologists and others to meet the needs of children with cataract in Africa. The geographic distribution of research, training, and programme development across Africa has been uneven; investment has been greatest in eastern and southern Africa. Population based surveys (using key informants) suggest that 15–35% of childhood blindness is due to congenital or developmental cataract. T...

  16. Cataract Extraction in High Myopic Eyes

    OpenAIRE

    Wan-Chen Ku; Lan-Hsin Chuang; Chi-Chun Lai

    2002-01-01

    Background: According to the high prevalence of myopia in Taiwan, we analyze theadopted cataract extractions, identify predicting factors for postoperativevision, and to assess the incidence of retinal complications after Nd: YAGlaser capsulotomy in high myopic eyes.Methods: One hundred and twenty-five eyes, which the axial lengths were longer than26 mm, following cataract extraction were enrolled. Surgeries adoptedincluded phacoemulsification with intraocular lens implantation, extracapsular...

  17. Retinal detachment following cataract surgery with capsulorhexis.

    OpenAIRE

    Kelley, J S; Doxanas, M T

    1995-01-01

    PURPOSE: To estimate the incidence of retinal detachment after cataract surgery with capsulorhexis. METHODS: A consecutive series of 2,150 cataract operations were followed for incidence of retinal detachment. A series of 1,000 patients from this group were analyzed for high risk factors: myopia, age, sex, operative complications and capsulotomy. RESULTS: With minimum one year follow up in 90% of patients the incidence of retinal detachment was 0.25% (5 cases). CONCLUSION: The true incidence ...

  18. Impairment of lacrimal drainage after cataract surgery

    OpenAIRE

    Hamid Fesharaki; Hasan Razmjoo; Masoud Aghajani

    2007-01-01

    BACKGROUND: Complaining of tearing was found in some of our patients after phacoemulsification surgery for senile cataract. Secondary acquired lacrimal drainage obstruction has been proposed to happen due to different causes. This study was performed at Feiz hospital in Isfahan, Iran from September to December of 2004 to evaluate the effects of phacoemulsification surgery on tear drainage in eyes with senile cataract. METHODS: This cohort study was performed on 110 patients with senile catara...

  19. Cataract extraction without retrobulbar anaesthetic injection.

    OpenAIRE

    Smith, R

    1990-01-01

    Extracapsular cataract extraction with lens implant under local anaesthesia consisting of amethocaine drops followed by a simple subconjunctival injection in the upper part of the globe but without a retrobulbar injection was carried out in 175 eyes of 165 patients. The purpose of the study was to establish the feasibility of this type of anaesthesia in cataract surgery with the principal object of avoiding the possibility of retrobulbar haemorrhage and the other, rarer, complications of retr...

  20. Current practice of cataract extraction and anaesthesia.

    OpenAIRE

    Hodgkins, P R; Luff, A J; Morrell, A. J.; Botchway, L. T.; Featherston, T. J.; Fielder, A R

    1992-01-01

    A questionnaire regarding preferred methods of cataract extraction and anaesthesia was sent to 456 consultant ophthalmologists in England and Wales. Replies were received from 86% (n = 392), 83% (n = 380) having completed the questionnaire in full. The most frequently employed surgical approach was non-automated extracapsular cataract extraction. Only 2% of surgeons (n = 8) used phacoemulsification routinely and 2% (n = 7) used intracapsular extraction. Intraocular lens implantation was the s...

  1. Progression of diabetic retinopathy after cataract extraction.

    OpenAIRE

    Pollack, A; Dotan, S.; Oliver, M.

    1991-01-01

    The course of diabetic retinopathy following cataract extraction was studied retrospectively in 89 patients (89 eyes). Cataract extraction was extracapsular in 12 eyes (13.5%), extracapsular with intraocular lens implantation in 37 (41.6%), and intracapsular in 40 (45%). In 55 eyes (61.8%) there was no change in the retinal status after surgery, and in 34 (38.2%) there was progression of diabetic retinopathy. In the eyes showing progression there was appearance or aggravation of non-prolifera...

  2. Involvement of midbrain tectum neurokinin-mediated mechanisms in fear and anxiety

    Energy Technology Data Exchange (ETDEWEB)

    Brenes, J.C. [Experimental and Physiological Psychology, Philipps-University of Marburg, Marburg (Germany); Broiz, A.C.; Bassi, G.S. [Instituto de Neurociências e Comportamento, Campus USP, Ribeirão Preto, SP (Brazil); Laboratório de Psicobiologia, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP (Brazil); Schwarting, R.K.W. [Experimental and Physiological Psychology, Philipps-University of Marburg, Marburg (Germany); Brandão, M.L. [Instituto de Neurociências e Comportamento, Campus USP, Ribeirão Preto, SP (Brazil); Laboratório de Psicobiologia, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP (Brazil)

    2012-03-09

    Electrical stimulation of midbrain tectum structures, particularly the dorsal periaqueductal gray (dPAG) and inferior colliculus (IC), produces defensive responses, such as freezing and escape behavior. Freezing also ensues after termination of dPAG stimulation (post-stimulation freezing). These defensive reaction responses are critically mediated by {sub Y}-aminobutyric acid and 5-hydroxytryptamine mechanisms in the midbrain tectum. Neurokinins (NKs) also play a role in the mediation of dPAG stimulation-evoked fear, but how NK receptors are involved in the global processing and expression of fear at the level of the midbrain tectum is yet unclear. The present study investigated the role of NK-1 receptors in unconditioned defensive behavior induced by electrical stimulation of the dPAG and IC of male Wistar rats. Spantide (100 pmol/0.2 µL), a selective NK-1 antagonist, injected into these midbrain structures had anti-aversive effects on defensive responses and distress ultrasonic vocalizations induced by stimulation of the dPAG but not of the IC. Moreover, intra-dPAG injections of spantide did not influence post-stimulation freezing or alter exploratory behavior in rats subjected to the elevated plus maze. These results suggest that NK-1 receptors are mainly involved in the mediation of defensive behavior organized in the dPAG. Dorsal periaqueductal gray-evoked post-stimulation freezing was not affected by intra-dPAG injections of spantide, suggesting that NK-1-mediated mechanisms are only involved in the output mechanisms of defensive behavior and not involved in the processing of ascending aversive information from the dPAG.

  3. Involvement of midbrain tectum neurokinin-mediated mechanisms in fear and anxiety

    International Nuclear Information System (INIS)

    Electrical stimulation of midbrain tectum structures, particularly the dorsal periaqueductal gray (dPAG) and inferior colliculus (IC), produces defensive responses, such as freezing and escape behavior. Freezing also ensues after termination of dPAG stimulation (post-stimulation freezing). These defensive reaction responses are critically mediated by Y-aminobutyric acid and 5-hydroxytryptamine mechanisms in the midbrain tectum. Neurokinins (NKs) also play a role in the mediation of dPAG stimulation-evoked fear, but how NK receptors are involved in the global processing and expression of fear at the level of the midbrain tectum is yet unclear. The present study investigated the role of NK-1 receptors in unconditioned defensive behavior induced by electrical stimulation of the dPAG and IC of male Wistar rats. Spantide (100 pmol/0.2 µL), a selective NK-1 antagonist, injected into these midbrain structures had anti-aversive effects on defensive responses and distress ultrasonic vocalizations induced by stimulation of the dPAG but not of the IC. Moreover, intra-dPAG injections of spantide did not influence post-stimulation freezing or alter exploratory behavior in rats subjected to the elevated plus maze. These results suggest that NK-1 receptors are mainly involved in the mediation of defensive behavior organized in the dPAG. Dorsal periaqueductal gray-evoked post-stimulation freezing was not affected by intra-dPAG injections of spantide, suggesting that NK-1-mediated mechanisms are only involved in the output mechanisms of defensive behavior and not involved in the processing of ascending aversive information from the dPAG

  4. Involvement of midbrain tectum neurokinin-mediated mechanisms in fear and anxiety

    Directory of Open Access Journals (Sweden)

    J.C. Brenes

    2012-04-01

    Full Text Available Electrical stimulation of midbrain tectum structures, particularly the dorsal periaqueductal gray (dPAG and inferior colliculus (IC, produces defensive responses, such as freezing and escape behavior. Freezing also ensues after termination of dPAG stimulation (post-stimulation freezing. These defensive reaction responses are critically mediated by γ-aminobutyric acid and 5-hydroxytryptamine mechanisms in the midbrain tectum. Neurokinins (NKs also play a role in the mediation of dPAG stimulation-evoked fear, but how NK receptors are involved in the global processing and expression of fear at the level of the midbrain tectum is yet unclear. The present study investigated the role of NK-1 receptors in unconditioned defensive behavior induced by electrical stimulation of the dPAG and IC of male Wistar rats. Spantide (100 pmol/0.2 μL, a selective NK-1 antagonist, injected into these midbrain structures had anti-aversive effects on defensive responses and distress ultrasonic vocalizations induced by stimulation of the dPAG but not of the IC. Moreover, intra-dPAG injections of spantide did not influence post-stimulation freezing or alter exploratory behavior in rats subjected to the elevated plus maze. These results suggest that NK-1 receptors are mainly involved in the mediation of defensive behavior organized in the dPAG. Dorsal periaqueductal gray-evoked post-stimulation freezing was not affected by intra-dPAG injections of spantide, suggesting that NK-1-mediated mechanisms are only involved in the output mechanisms of defensive behavior and not involved in the processing of ascending aversive information from the dPAG.

  5. Peripheral and Central Mechanisms Involved in the Hormonal Control of Male and Female Reproduction.

    Science.gov (United States)

    Rudolph, L M; Bentley, G E; Calandra, R S; Paredes, A H; Tesone, M; Wu, T J; Micevych, P E

    2016-07-01

    Reproduction involves the integration of hormonal signals acting across multiple systems to generate a synchronised physiological output. A critical component of reproduction is the luteinising hormone (LH) surge, which is mediated by oestradiol (E2 ) and neuroprogesterone interacting to stimulate kisspeptin release in the rostral periventricular nucleus of the third ventricle in rats. Recent evidence indicates the involvement of both classical and membrane E2 and progesterone signalling in this pathway. A metabolite of gonadotrophin-releasing hormone (GnRH), GnRH-(1-5), has been shown to stimulate GnRH expression and secretion, and has a role in the regulation of lordosis. Additionally, gonadotrophin release-inhibitory hormone (GnIH) projects to and influences the activity of GnRH neurones in birds. Stress-induced changes in GnIH have been shown to alter breeding behaviour in birds, demonstrating another mechanism for the molecular control of reproduction. Peripherally, paracrine and autocrine actions within the gonad have been suggested as therapeutic targets for infertility in both males and females. Dysfunction of testicular prostaglandin synthesis is a possible cause of idiopathic male infertility. Indeed, local production of melatonin and corticotrophin-releasing hormone could influence spermatogenesis via immune pathways in the gonad. In females, vascular endothelial growth factor A has been implicated in an angiogenic process that mediates development of the corpus luteum and thus fertility via the Notch signalling pathway. Age-induced decreases in fertility involve ovarian kisspeptin and its regulation of ovarian sympathetic innervation. Finally, morphological changes in the arcuate nucleus of the hypothalamus influence female sexual receptivity in rats. The processes mediating these morphological changes have been shown to involve the rapid effects of E2 controlling synaptogenesis in this hypothalamic nucleus. In summary, this review highlights new

  6. Changes in intraocular pressure and anterior segment morphometry after uneventful phacoemulsification cataract surgery.

    LENUS (Irish Health Repository)

    Dooley, I

    2012-02-01

    PURPOSE: To study changes in anterior segment morphometry after uneventful phacoemulsification cataract surgery, and to investigate whether there is a relationship between any observed changes and intraocular pressure (IOP) reduction after the procedure. METHODS: The anterior chamber depth (ACD), anterior chamber volume (ACV), anterior chamber angle (ACA), central corneal thickness (CCT), and IOP were measured in 101 non-glaucomatous eyes before and after uneventful phacoemulsification cataract surgery. RESULTS: After cataract surgery, the mean ACD, ACV, and ACA values increased by 1.08 mm, 54.4 mm(3), and 13.1 degrees , respectively, and the mean IOP (corrected for CCT) decreased by 3.2 mm Hg. The predictive value of a previously described index (preoperative ACD\\/preoperative IOP (corrected for CCT) or CPD ratio) for IOP (corrected for CCT) reduction after cataract surgery was confirmed, reflected in an r(2) value of 23.3% between these two parameters (P<0.001). Other indices predictive of IOP reduction after cataract surgery were also identified, including preoperative IOP\\/preoperative ACV and preoperative IOP\\/preoperative ACA, reflected in r(2) values of 13.7 and 13.7%, respectively (P<0.001 and P<0.001, respectively). CONCLUSIONS: Our study confirms the predictive value of the CPD ratio for IOP reduction after cataract surgery, and may contribute to the decision-making process in patients with glaucoma or ocular hypertension. Furthermore, two novel indices of preoperative parameters that are predictive for IOP reduction after cataract surgery were identified, and enhance our understanding of the mechanisms underlying IOP changes after this procedure.

  7. Can drugs or micronutrients prevent cataract?

    Science.gov (United States)

    Harding, J J

    2001-01-01

    Cataract is the major cause of blindness and of visual impairment worldwide, so its prevention is of the greatest importance. At present no drug therapy is licensed for use in the UK or the US, so the only treatment for cataract is by surgery, which is expensive and has adverse effects. This article reviews research on prevention of cataract by a variety of agents, including micronutrients as well as drugs. Benefits have been claimed for many compounds or mixtures and this review concentrates on those most extensively studied. Information on possible benefits of putative anticataract agents comes from a variety of approaches, from laboratory experiments, both in vitro and in vivo, to epidemiological studies in patients. Sorbitol-lowering drugs were the first to be examined systematically and progressed to clinical trials which were disappointing, and now the entire rationale for their use in prevention of cataract is questionable. Micronutrients showed little promise in animals but came to clinical trial in patients with cataract without the publication of any major benefit. Pantethine showed more promise in animal studies but the only clinical trial was abandoned early. A variety of laboratory and epidemiological evidence supports the benefits of aspirin-like drugs but there has been no trial specifically in patients with cataract. Add-on studies to trials of aspirin for other indications have not been encouraging. Research into other compounds is interesting but less advanced. PMID:11482741

  8. Phytoremediation potential of the novel atrazine tolerant Lolium multiflorum and studies on the mechanisms involved

    International Nuclear Information System (INIS)

    Atrazine impact on human health and the environment have been extensively studied. Phytoremediation emerged as a low cost, environmental friendly biotechnological solution for atrazine pollution in soil and water. In vitro atrazine tolerance assays were performed and Lolium multiflorum was found as a novel tolerant species, able to germinate and grow in the presence of 1 mg kg-1 of the herbicide. L. multiflorum presented 20% higher atrazine removal capacity than the natural attenuation, with high initial degradation rate in microcosms. The mechanisms involved in atrazine tolerance such as mutation in psbA gene, enzymatic detoxification via P450 or chemical hydrolysis through benzoxazinones were evaluated. It was demonstrated that atrazine tolerance is conferred by enhanced enzymatic detoxification via P450. Due to its atrazine degradation capacity in soil and its agronomical properties, L. multiflorum is a candidate for designing phytoremediation strategies for atrazine contaminated agricultural soils, especially those involving run-off avoiding. - Finding of a novel atrazine-tolerant species, as a potential candidate for phytoremediating herbicide-contaminated agriculture soils and elucidation of the mechanisms involved in tolerance.

  9. Phytoremediation potential of the novel atrazine tolerant Lolium multiflorum and studies on the mechanisms involved

    Energy Technology Data Exchange (ETDEWEB)

    Merini, Luciano J. [Catedra de Microbiologia Industrial y Biotecnologia, Universidad de Buenos Aires (Argentina); Bobillo, Cecilia [Servicio de Huellas Digitales Geneticas, Facultad de Farmacia y Bioquimica, Microbiologia Industrial y Biotecnologia, Universidad de Buenos Aires, Junin 956, BS As (Argentina); Cuadrado, Virginia [Catedra de Microbiologia Industrial y Biotecnologia, Universidad de Buenos Aires (Argentina); Corach, Daniel [Servicio de Huellas Digitales Geneticas, Facultad de Farmacia y Bioquimica, Microbiologia Industrial y Biotecnologia, Universidad de Buenos Aires, Junin 956, BS As (Argentina); Giulietti, Ana M., E-mail: agiule@ffyb.uba.a [Catedra de Microbiologia Industrial y Biotecnologia, Universidad de Buenos Aires (Argentina)

    2009-11-15

    Atrazine impact on human health and the environment have been extensively studied. Phytoremediation emerged as a low cost, environmental friendly biotechnological solution for atrazine pollution in soil and water. In vitro atrazine tolerance assays were performed and Lolium multiflorum was found as a novel tolerant species, able to germinate and grow in the presence of 1 mg kg{sup -1} of the herbicide. L. multiflorum presented 20% higher atrazine removal capacity than the natural attenuation, with high initial degradation rate in microcosms. The mechanisms involved in atrazine tolerance such as mutation in psbA gene, enzymatic detoxification via P{sub 450} or chemical hydrolysis through benzoxazinones were evaluated. It was demonstrated that atrazine tolerance is conferred by enhanced enzymatic detoxification via P{sub 450}. Due to its atrazine degradation capacity in soil and its agronomical properties, L. multiflorum is a candidate for designing phytoremediation strategies for atrazine contaminated agricultural soils, especially those involving run-off avoiding. - Finding of a novel atrazine-tolerant species, as a potential candidate for phytoremediating herbicide-contaminated agriculture soils and elucidation of the mechanisms involved in tolerance.

  10. Differential gene expression in seasonal sympatry: mechanisms involved in diverging life histories.

    Science.gov (United States)

    Fudickar, Adam M; Peterson, Mark P; Greives, Timothy J; Atwell, Jonathan W; Bridge, Eli S; Ketterson, Ellen D

    2016-03-01

    In an era of climate change, understanding the genetic and physiological mechanisms underlying flexibility in phenology and life history has gained greater importance. These mechanisms can be elucidated by comparing closely related populations that differ in key behavioural and physiological traits such as migration and timing of reproduction. We compared gene expression in two recently diverged dark-eyed Junco ( Junco hyemalis) subspecies that live in seasonal sympatry during winter and early spring, but that differ in behaviour and physiology, despite exposure to identical environmental cues. We identified 547 genes differentially expressed in blood and pectoral muscle. Genes involved in lipid transport and metabolism were highly expressed in migrant juncos, while genes involved in reproductive processes were highly expressed in resident breeders. Seasonal differences in gene expression in closely related populations residing in the same environment provide significant insights into mechanisms underlying variation in phenology and life history, and have potential implications for the role of seasonal timing differences in gene flow and reproductive isolation. PMID:26979563

  11. Assessment of Mechanisms Involved in Antinociception Produced by the Alkaloid Caulerpine

    Directory of Open Access Journals (Sweden)

    Luiz Henrique Agra Cavalcante-Silva

    2014-09-01

    Full Text Available In previous works we showed that oral administration of caulerpine, a bisindole alkaloid isolated from algae of the genus Caulerpa, produced antinociception when assessed in chemical and thermal models of nociception. In this study, we evaluated the possible mechanism of action of this alkaloid in mice, using the writhing test. The antinociceptive effect of caulerpine was not affected by intraperitoneal (i.p. pretreatment of mice with naloxone, flumazenil, l-arginine or atropine, thus discounting the involvement of the opioid, GABAergic, l-arginine-nitric oxide and (muscarinic cholinergic pathways, respectively. In contrast, i.p. pretreatment with yohimbine, an α2-adrenoceptor antagonist, or tropisetron, a 5-HT3 antagonist, significantly blocked caulerpine-induced antinociception. These results suggest that caulerpine exerts its antinociceptive effect in the writhing test via pathways involving α2-adrenoceptors and 5-HT3 receptors. In summary, this alkaloid could be of interest in the development of new dual-action analgesic drugs.

  12. Absorption of Carotenoids and Mechanisms Involved in Their Health-Related Properties.

    Science.gov (United States)

    Cervantes-Paz, Braulio; Victoria-Campos, Claudia I; Ornelas-Paz, José de Jesús

    2016-01-01

    Carotenoids participate in the normal metabolism and function of the human body. They are involved in the prevention of several diseases, especially those related to the inflammation syndrome. Their main mechanisms of action are associated to their potent antioxidant activity and capacity to regulate the expression of specific genes and proteins. Recent findings suggest that carotenoid metabolites may explain several processes where the participation of their parent carotenoids was unclear. The health benefits of carotenoids strongly depend on their absorption and transformation during gastrointestinal digestion. The estimation of the 'bioaccessibility' of carotenoids through in vitro models have made possible the evaluation of the effect of a large number of factors on key stages of carotenoid digestion and intestinal absorption. The bioaccessibility of these compounds allows us to have a clear idea of their potential bioavailability, a term that implicitly involves the biological activity of these compounds. PMID:27485232

  13. Ocular coherence tomography of symptomatic phototoxic retinopathy after cataract surgery: a case report

    Directory of Open Access Journals (Sweden)

    Yunis Muhammad H

    2011-04-01

    Full Text Available Abstract Introduction High-resolution ocular coherence computed tomography enables unprecedented visualization of the retinal microarchitecture. To the best of our knowledge, this is the first report of high-resolution ocular coherence tomography findings in the healed form of photic post-cataract retinopathy. Case presentation A 76-year-old Caucasian man complained of paracentral scotoma, persisting for six weeks after cataract surgery. Conclusion Ocular coherence tomography demonstrated a localized juxta-foveal area of retinal atrophy involving the photoreceptor layer, and the retinal pigment epithelium layer.

  14. Reversible Cataract as the Presenting Sign of Diabetes Mellitus: Report of Two Cases and Literature Review

    OpenAIRE

    Xiu Min Wang; Li Liang; Chao Chun Zou; Ke Huang; Yan Yan Jin; Ji Jin

    2012-01-01

    Background: Type 1 diabetes mellitus (T1DM) is the most common form of diabetes in young children. Serious optic complications, e.g. diabetic retinopathy and diabetic cataract involvement, are not usually detected in T1DM patients at the onset of the disease.Case Presentation: Two girls aged 11 years and 9 years were hospitalized in our unit in 2008 and 2009. They presented cataracts 1 and 6 months before the diagnosis of T1DM, respectively. After blood glucose level was controlled by insulin...

  15. Cataract incidence after total-body irradiation

    International Nuclear Information System (INIS)

    Purpose: Aim of this retrospective study was to evaluate cataract incidence in a homogeneous group of patients after total-body irradiation followed by autologous bone marrow transplantation or peripheral blood stem cell transplantation. Method and Materials: Between 11/1982 and 6/1994 in total 260 patients received in our hospital total-body irradiation for treatment of haematological malignancy. In 1996-96 patients out of these 260 patients were still alive. 85 from these still living patients (52 men, 33 women) answered evaluable on a questionnaire and could be examined ophthalmologically. Median age of these patients was 38,5 years (15 - 59 years) at time of total-body irradiation. Radiotherapy was applied as hyperfractionated total-body irradiation with a median dose of 14,4 Gy in 12 fractions over 4 days. Minimum time between fractions was 4 hours, photons with a energy of 23 MeV were used, and the dose rate was 7 - 18 cGy/min. Results: Median follow-up is now 5,8 years (1,7 - 13 years). Cataract occurred in (28(85)) patients after a median time of 47 months (1 - 104 months). In 6 out of these 28 patients who developed a cataract, surgery of the cataract was performed. Whole-brain irradiation prior to total-body irradiation was more often in the group of patients developing a cataract (14,3%) vs. 10,7% in the group of patients without cataract. Conclusion: Cataract is a common side effect of total-body irradiation. Cataract incidence found in our patients is comparable to results of other centres using a fractionated regimen for total-body irradiation. The hyperfractionated regimen used in our hospital does obviously not result in a even lower cataract incidence. In contrast to acute and late toxicity in other organ/organsystems, hyperfractionation of total-body irradiation does not further reduce toxicity for the eye-lens. Dose rate may have more influence on cataract incidence

  16. Pathogenic Mechanisms Involved in the Hematological Alterations of Arenavirus-induced Hemorrhagic Fevers

    Directory of Open Access Journals (Sweden)

    Roberto G. Pozner

    2013-01-01

    Full Text Available Viral hemorrhagic fevers (VHFs caused by arenaviruses are acute diseases characterized by fever, headache, general malaise, impaired cellular immunity, eventual neurologic involvement, and hemostatic alterations that may ultimately lead to shock and death. The causes of the bleeding are still poorly understood. However, it is generally accepted that these causes are associated to some degree with impaired hemostasis, endothelial cell dysfunction and low platelet counts or function. In this article, we present the current knowledge about the hematological alterations present in VHF induced by arenaviruses, including new aspects on the underlying pathogenic mechanisms.

  17. Multiple mechanisms involved in oxytocin-induced modulation of myometrial contractility

    Institute of Scientific and Technical Information of China (English)

    Anatoly SHMYGOL; Joanna GULLAM; Andrew BLANKS; Steven THORNTON

    2006-01-01

    Oxytocin is a small peptide hormone with multiple sites of action in human body.It regulates a large number of reproduction-related processes in all species.Particularly important is its ability to stimulate uterine contractility.This is achieved by multiple mechanisms involving sarcoplasmic reticulum Ca2+ release and sensitization of the contractile apparatus to Ca2+.In this paper,we review the data published by US and other groups on oxytocin-induced modulation of uterine contractility.We conclude that sensitization of contractile apparatus to Ca2+ is the most relevant physiological effect of oxytocin on human myometrium.

  18. The mechanism of sperm-egg interaction and the involvement of IZUM01 in fusion

    Institute of Scientific and Technical Information of China (English)

    Naokazu Inoue; Masahito Ikawa; Masaru Okabe

    2011-01-01

    An average human ejaculate contains over 100 million sperm,but only a few succeed in accomplishing the journey to an egg by migration through the female reproductive tract.Among these few sperm,only one participates in fertilization.There might be an ingenious molecular mechanism to ensure that the very best sperm fertilize an egg.However,recent gene disruption experiments in mice have revealed that many factors previously described as important for fertilization are largely dispensable.One could argue that the fertilization mechanism is made robust against gene disruptions.However,this is not likely,as there are already six different gene-disrupted mouse lines (Calmegin,Adam1a,Adam2,Adam3,Aceand Pgap1),all of which result in male sterility.The sperm from these animals are known to have defective zona-binding ability and at the same time lose oviduct-migrating ability.Concerning spermzona binding,the widely accepted involvement of sugar moiety on zona pellucida 3 (ZP3) is indicated to be dispensable by gene disruption experiments.Thus,the landscape of the mechanism of fertilization is revolving considerably.In the sperm-egg fusion process,CD9 on egg and IZUM01 on sperm have emerged as essential factors.This review focuses on the mechanism of fertilization elucidated by gene-manipulated animals.

  19. Mechanism of electron transfer reaction of ternary dipicolinatochromium(III) complex involving oxalate as secondary ligand

    Indian Academy of Sciences (India)

    Hassan Amroun Ewais; Iqbal Mohamed Ibrhium Ismail

    2013-09-01

    Mechanism of electron transfer reaction of ternary Mechanism of the oxidation of [CrIII(DPA)(OX)(H2O)]− (DPA = dipicolinate and OX = oxalate) by periodate in aqueous acidic medium has been studied spectrophotometrically over the pH range of 4.45-5.57 at different temperatures. The reaction is first order with respect to both [IO$^{−}_{4}$] and the complex concentration, and it obeys the following rate law: $$d[{\\text Cr}^{\\text{VI}}]/dt = k_6K_4K_6[{\\text IO}^−_4][{\\text{Cr}}^{\\text{III}}]_{\\text{T}}/\\{([H^+] + K_4) + (K_5[H+] + K_6K_4)[{\\text{IO}}^{−}_{4}]\\}.$$ The rate of the reaction increases with increasing pH due to the deprotonation equilibria of the complex. The experimental rate law is consistent with a mechanism in which the deprotonated form [CrIII(DPA)(OX)(OH)]2− is more reactive than the conjugated acid. It is proposed that electron transfer proceeds through an inner-sphere mechanism via coordination of IO$^{−}_{4}$ to chromium(III). Thermodynamic activation parameters were calculated using the transition state theory equation.dipicolinatochromium(III) complex involving oxalate as secondary ligand

  20. Soil biochar amendment as a climate change mitigation tool: Key parameters and mechanisms involved.

    Science.gov (United States)

    Brassard, Patrick; Godbout, Stéphane; Raghavan, Vijaya

    2016-10-01

    Biochar, a solid porous material obtained from the carbonization of biomass under low or no oxygen conditions, has been proposed as a climate change mitigation tool because it is expected to sequester carbon (C) for centuries and to reduce greenhouse gas (GHG) emissions from soils. This review aimed to identify key biochar properties and production parameters that have an effect on these specific applications of the biochar. Moreover, mechanisms involved in interactions between biochar and soils were highlighted. Following a compilation and comparison of the characteristics of 76 biochars from 40 research studies, biochars with a lower N content, and consequently a higher C/N ratio (>30), were found to be more suitable for mitigation of N2O emissions from soils. Moreover, biochars produced at a higher pyrolysis temperature, and with O/C ratio <0.2, H/Corg ratio <0.4 and volatile matter below 80% may have high C sequestration potential. Based on these observations, biochar production and application to the field can be used as a tool to mitigate climate change. However, it is important to determine the pyrolysis conditions and feedstock needed to produce a biochar with the desired properties for a specific application. More research studies are needed to identify the exact mechanisms involved following biochar amendment to soil. PMID:27420171

  1. Antinociceptive Activity of Methanol Extract of Muntingia calabura Leaves and the Mechanisms of Action Involved

    Directory of Open Access Journals (Sweden)

    M. H. Mohd. Sani

    2012-01-01

    Full Text Available Muntingia calabura L. (family Elaeocarpaceae has been traditionally used to relieve various pain-related ailments. The present study aimed to determine the antinociceptive activity of methanol extract of M. calabura leaves (MEMC and to elucidate the possible mechanism of antinociception involved. The in vivo chemicals (acetic acid-induced abdominal constriction and formalin-, capsaicin-, glutamate-, serotonin-induced paw licking test and thermal (hot plate test models of nociception were used to evaluate the extract antinociceptive activity. The extract (100, 250, and 500 mg/kg was administered orally 60 min prior to subjection to the respective test. The results obtained demonstrated that MEMC produced significant (P<0.05 antinociceptive response in all the chemical- and thermal-induced nociception models, which was reversed after pretreatment with 5 mg/kg naloxone, a non-selective opioid antagonist. Furthermore, pretreatment with L-arginine (a nitric oxide (NO donor, NG-nitro-L-arginine methyl esters (L-NAME; an inhibitor of NO synthase (NOS, methylene blue (MB; an inhibitor of cyclic-guanosine monophosphate (cGMP pathway, or their combination also caused significant (P<0.05 change in the intensity of the MEMC antinociception. In conclusion, the MEMC antinociceptive activity involves activation of the peripheral and central mechanisms, and modulation via, partly, the opioid receptors and NO/cGMP pathway.

  2. Tools to fight the cataract epidemic: A review of experimental animal models that mimic age related nuclear cataract.

    Science.gov (United States)

    Lim, Julie C; Umapathy, Ankita; Donaldson, Paul J

    2016-04-01

    Cataract is the leading cause of blindness worldwide and accounts for approximately half of all forms of vision loss. Currently, the only way to treat cataracts is by surgery. However, with an ageing population, the demand for surgery and the need for cost effective alternative solutions grows exponentially. To reduce the need for cataract surgery, alternative medical therapies to delay cataracts are urgently required. However, given the difficulty in accessing human cataract lenses, investigating the process of cataract formation and testing the efficacy of potential therapies in humans is problematic. Therefore, researchers have looked to create suitable animal models of cataractogenesis to identify therapeutic options. This review will provide an overview of the cataract specific changes previously reported in human cataract lenses, before focussing on the specific changes that occur in age related nuclear (ARN) cataract, the most common form of cataract in humans. This will be followed by a discussion of a range of existing animal cataract models and their respective suitability for mimicking the processes associated with the development of ARN cataract, and therefore their utility as models to test anti-cataract therapies for future use in humans. PMID:26391448

  3. Healthy Amount of Vitamin C Might Keep Cataracts at Bay

    Science.gov (United States)

    ... cataracts occur naturally with age and cause the eye's lens to become cloudy. Cataracts can be removed but ... prevent oxidation that leads to clouding of the eye lens. A vitamin C-rich diet may boost the ...

  4. The first cataract surgeons in Latin America: 1611–1830

    Science.gov (United States)

    Leffler, Christopher T; Wainsztein, Ricardo D

    2016-01-01

    We strove to identify the earliest cataract surgeons in Latin America. Probably by 1611, the Genovese oculist Francisco Drago was couching cataracts in Mexico City. The surgeon Melchor Vásquez de Valenzuela probably performed cataract couching in Lima by 1697. Juan Peré of France demonstrated cataract couching in Veracruz and Mexico City between 1779 and 1784. Juan Ablanedo of Spain performed couching in Veracruz in 1791. Cataract extraction might have been performed in Havana and Caracas by 1793 and in Mexico by 1797. The earliest contemporaneously documented cataract extractions in Latin America were performed in Guatemala City by Narciso Esparragosa in 1797. In addition to Esparragosa, surgeons born in the New World who established the academic teaching of cataract surgery included José Miguel Muñoz in Mexico and José María Vargas in Caracas. Although cataract surgery came quite early to Latin America, its availability was initially inconsistent and limited. PMID:27143845

  5. Acute pulmonary oedema due to single dose acetazolamide taken after cataract surgery.

    Science.gov (United States)

    Guven Yilmaz, Suzan; Palamar, Melis; Gurgun, Cemil

    2016-01-01

    An increase in intraocular pressure following cataract surgery is very common. The main reason for this condition is viscoelastic agent remaining in the eye, which leads to mechanical obstruction of the trabecular meshwork. Prophylaxis with oral acetazolamide is frequently practised to prevent this early rise in intraocular pressure in the preoperative and postoperative periods. We report a case of an 81-year-old man with acute pulmonary oedema due to prophylactic acetazolamide intake after cataract surgery. The case is presented in order to draw attention to this serious complication. PMID:27170607

  6. High molecular weight protein aggregates in X-ray-induced cataract

    International Nuclear Information System (INIS)

    The nature and possible mechanism of formation of high molecular weight (HMW) protein aggregates were studied in X-ray-induced cataract in rabbit. The HMW protein fraction (molecular weight > 4 x 106daltons) which constituted approximately 18% of the total soluble protein in both the cataractous cortex and nucleus was isolated by gel filtration chromatography. The concentration of sulfhydryl (-SH) groups was three times higher than in normal α-crystallin. Increased oxidation of protein -SH groups was observed during the final stage of cataract. Treatment of HMW protein with dithioerythritol and subsequent refractionation yielded two peaks (1 and 11) eluting in similar positions to α- and β-crystallin. The electrophoretic mobilities and amino acid compositions of peaks 1 and 11 were similar to those of α- and β-crystallin respectively, with the major exception that the hydrolysates of proteins in both peaks were nearly lacking in tyrosine. (author)

  7. Role of the endocannabinoid system in the mechanisms involved in the LPS-induced preterm labor.

    Science.gov (United States)

    Bariani, María Victoria; Domínguez Rubio, Ana Paula; Cella, Maximiliano; Burdet, Juliana; Franchi, Ana María; Aisemberg, Julieta

    2015-12-01

    Prematurity is the leading cause of perinatal morbidity and mortality worldwide. There is a strong causal relationship between infection and preterm births. Intrauterine infection elicits an immune response involving the release of inflammatory mediators like cytokines and prostaglandins (PG) that trigger uterine contractions and parturition events. Anandamide (AEA) is an endogenous ligand for the cannabinoid receptors CB1 and CB2. Similarly to PG, endocannabinoids are implicated in different aspects of reproduction, such as maintenance of pregnancy and parturition. Little is known about the involvement of endocannabinoids on the onset of labor in an infectious milieu. Here, using a mouse model of preterm labor induced by lipopolysaccharide (LPS), we explored changes on the expression of components of endocannabinoid system (ECS). We have also determined whether AEA and CB antagonists alter PG production that induces labor. We observed an increase in uterine N-acylphosphatidylethanolamine-specific phospholipase D expression (NAPE-PLD, the enzyme that synthesizes AEA) upon LPS treatment. Activity of catabolic enzyme fatty acid amide hydrolase (FAAH) did not change significantly. In addition, we also found that LPS modulated uterine cannabinoid receptors expression by downregulating Cb2 mRNA levels and upregulating CB1 protein expression. Furthermore, LPS and AEA induced PGF2a augmentation, and this was reversed by antagonizing CB1 receptor. Collectively, our results suggest that ECS may be involved in the mechanism by which infection causes preterm birth. PMID:26347521

  8. Minocycline mechanism of neuroprotection involves the Bcl-2 gene family in optic nerve transection.

    Science.gov (United States)

    Levkovitch-Verbin, Hani; Waserzoog, Yael; Vander, Shelly; Makarovsky, Daria; Ilia, Piven

    2014-10-01

    The second-generation tetracycline, minocycline, has been shown to exhibit neuroprotective therapeutic benefits in many neurodegenerative diseases including experimental glaucoma and optic nerve transection (ONT). This study investigated the mechanism underlying minocycline neuroprotection in a model of ONT. ONT was applied unilaterally in 36 Wistar rat eyes. The rats were randomly divided into a minocycline (22 mg/kg/d) treatment group and a saline treatment group (control). Treatment (minocycline or saline) was given by intraperitoneal injections initiated 3 d before ONT and continued daily until the end of the experiment. The involvement of pro-apoptotic, pro-survival and inflammatory pathways was analyzed by quantitative Real-Time Polymerase Chain Reaction at 4 h and 3 d after the transection in both treatment groups. The involvement of Bcl-2 protein was evaluated by immunohistochemistry. We found that Minocycline significantly increased the expression of the antiapoptotic gene bcl-2 4 h after transection (n = 8, p = 0.008) and decreased the expression of Bax at the same time point (n = 8, p = 0.03). Tumor Necrosis Factor α (TNFα), Inhibitor of Apoptosis Protein (IAP1) and Gadd45α were significantly upregulated in the retinas of eyes with ONTs compared to control (n = 10 for each gene, p = 0.02, p = 0.03, p = 0.04, respectively) but this effect was unaffected by minocycline. This study further support that the mechanism underlying minocycline neuroprotection involves the Bcl-2 gene family, suggesting that minocycline has antiapoptotic properties that support its value as a promising neuroprotective drug. PMID:24410139

  9. Evolution of cataract surgery: Smaller incision - less complications

    OpenAIRE

    Draganić Vladimir; Vukosavljević Miroslav; Milivojević Milorad; Resan Mirko; Petrović Nenad

    2012-01-01

    Background/Aim. Cataract surgery has become one of the safest procedures in medicine thanks to advances in technology and surgical techniques. Although minimal, we still witness different complications. The aim of this study was to compare visual outcome and complication rate in different techniques of cataract surgery, ie in cataract surgeries with various corneal incision width. Methods. The study included 3,457 consecutive patients, ie 4,670 eyes that had undergone cataract surgery. ...

  10. High-Fidelity Cataract Surgery Simulation and Third World Blindness

    OpenAIRE

    Singh, Ajay; Strauss, Glenn H.

    2015-01-01

    The burden of global cataract blindness continues to rise, because the number of surgical ophthalmologists is insufficient, and they are unevenly distributed. There is an urgent need to train surgeons quickly and comprehensively in high-quality, low-cost cataract removal techniques. The authors suggest manual small-incision cataract surgery as a safe alternative to phacoemulsification cataract surgery in the developing world. They discuss the development of a novel, full-immersion, physics-ba...

  11. PROGNOSIS, PREVENTION, AND TREATMENT OF DIABETIC CATARACT SURGERY POSTOPERATIVE COMPLICATIONS

    OpenAIRE

    M. A. Kovalevskaya; N. V. Vedrintseva; L. A. Filina; T. Yu. Perova

    2015-01-01

    Aim. To study immune and antioxidant status of diabetic cataract patients and to assess the efficacy of preoperative preparation for diabetic cataract surgery to prevent intra- and postoperative complications and the efficacy of cataract treatment in metabolic syndrome patients. Patients and methods. 136 cataract patients (272 eyes) were examined (mean age 62±3.2 years). Among these patients, women predominated (n = 74). Control group included 25 healthy volunteers (10 men and 15 women) aged ...

  12. A study of awareness and knowledge about cataract among students

    OpenAIRE

    Sanjeev Kumar Puri; Suma Elangovan

    2016-01-01

    Background: Cataract can cause visual dysfunction ranging from mild to severe loss of vision. The rate of development of senile cataract is generally slow and the vision loss is usually gradual but can result in blindness if treatment is delayed. The main objective was to study the awareness about cataract among students (non-medical). Methods: A questionnaire based study was conducted among 430 students (non-medical). The questions tested their awareness about cataract and also about the...

  13. Cataract Surgical Outcomes In Diabetic Patients: Case Control Study

    OpenAIRE

    Onakpoya Oluwatoyin; Bekibele Charles; Adegbehingbe Stella

    2009-01-01

    Purpose: To determine the visual outcome of cataract surgery in diabetes mellitus with advanced cataract in a tertiary institution in Nigeria. Design: A retrospective case control study conducted at the University College Hospital, Ibadan Nigeria. Subjects: Twenty three consecutive patients with diabetes and 23 age and sex matched non-diabetic control patients who had extracapsular cataract extraction for advanced cataract between 2002-2005. Main outcome: Mean post operative visual acu...

  14. Тhe shifts in the content of prostoglandins Е2 in aqueous humor of patients with senile and complicated cataracts

    Directory of Open Access Journals (Sweden)

    A.A. Zilfyan

    2013-03-01

    Full Text Available Abstract Purpose. There has been undertaken in this research, in case of complicated cataracts, an attempt of definition of a role of prostaglandins Е2 (PgЕ2 in mechanisms of cancellation of immune responses, responsible for ACAID, in the early period of the aseptic uveitis course. Material and method. The patients with senile and complicated cataracts underwent the microaxial phonoemulsification. The first group included patients with senile uncomplicated cataract (400 eyes, the second one – with cataract, proceeding associated with primary open-angled glaucoma (200 eyes, the third group – with cataract, proceeding associated with pseudoexfoliative glaucoma (200 eyes, the fourth group – with cataract, proceeding associated with arterial hypertension (300 eyes, the fifth one – with cataract, proceeding associated with diabetes mellitus (100 eyes, and the sixth group – with cataract, proceeding associated with previous trauma (100 eyes. The studied contingent of patients has been examined using subjective and objective methods of research standard in ophthalmology. Aqueous humor of patients of all six studied groups (80 tests in each group was subjected to immunoenzymatic level definition of prostaglandins Е2, using kits of the firm DRG International Inc. (USA. The content of prostaglandins Е2 was expressed in pg/ml. Immunoenzymatic researches (ELISA were conducted with the autoanalyzer «Stat Fax 3200» (USA in wavelengths of absorption of 420-450 nm. The obtained results were statistically analyzed, using the Student criteria and the SPSS-13 software. Results. In case of complicated cataracts, namely cataracts, proceeding associated with open-angle and pseudoexfoliative glaucoma, and also in traumatic cataracts, an inflammatory process in form of anterior aseptic uveitis was observed in the early post-operative period. Relative high indices of prostaglandins Е2 were determined in the aqueous humor of the above

  15. Mouse models of congenital cataract.

    Science.gov (United States)

    Graw, J

    1999-06-01

    Mouse mutants affecting lens development are excellent models for corresponding human disorders. The mutant aphakia has been characterised by bilaterally aphakic eyes (Varnum and Stevens, J Hered 1968;59:147-50); the corresponding gene was mapped to chromosome 19 (Varnum and Stevens, Mouse News Lett 1975;53:35). Recent investigations in our laboratory refined the linkage of 0.6 cM proximal to the marker D19Mit10. Several candidate genes have been excluded (Chuk1, Fgf8, Lbp1, Npm3, Pax2, Pitx3). The Cat3 mutations are characterised by vacuolated lenses caused by alterations in the initial secondary lens fibre cell differentiation. Secondary malformations develop at the cornea and iris, but the retina remains unaffected. The mutation has been mapped to chromosome 10 close to the markers D10Mit41 and D10Mit95. Several candidate genes have been excluded (Dcn, Elk3, Ldc, Mell8, Tr2-11). The series of Cat2 mutations have been mapped close to the gamma-crystallin genes (Cryg; Löster et al., Genomics 1994;23:240-2). The Cat2nop mutation is characterised by a mutation in the third exon of Crygb leading to a truncated gamma B-crystallin and the termination of lens fibre cell differentiation. The Cat2 mutants are interesting models for human cataracts caused by mutations in the human CRYG genes at chromosome 2q32-35. PMID:10627821

  16. Two-step mechanism involving active-site conformational changes regulates human telomerase DNA binding.

    Science.gov (United States)

    Tomlinson, Christopher G; Moye, Aaron L; Holien, Jessica K; Parker, Michael W; Cohen, Scott B; Bryan, Tracy M

    2015-01-15

    The ribonucleoprotein enzyme telomerase maintains telomeres and is essential for cellular immortality in most cancers. Insight into the telomerase mechanism can be gained from syndromes such as dyskeratosis congenita, in which mutation of telomerase components manifests in telomere dysfunction. We carried out detailed kinetic and thermodynamic analyses of wild-type telomerase and two disease-associated mutations in the reverse transcriptase domain. Differences in dissociation rates between primers with different 3' ends were independent of DNA affinities, revealing that initial binding of telomerase to telomeric DNA occurs through a previously undescribed two-step mechanism involving enzyme conformational changes. Both mutations affected DNA binding, but through different mechanisms: P704S specifically affected protein conformational changes during DNA binding, whereas R865H showed defects in binding to the 3' region of the DNA. To gain further insight at the structural level, we generated the first homology model of the human telomerase reverse transcriptase domain; the positions of P704S and R865H corroborate their observed mechanistic defects, providing validation for the structural model. Our data reveal the importance of protein interactions with the 3' end of telomeric DNA and the role of protein conformational change in telomerase DNA binding, and highlight naturally occurring disease mutations as a rich source of mechanistic insight. PMID:25365545

  17. SMALL INCISION CATARACT SURGERY VERSUS PHACOEMULSIFICATION FOR IMMATURE CATARACT: A SINGLE BLIND RANDOMIZED CONTROLLED TRIAL

    Directory of Open Access Journals (Sweden)

    Md. Jawed

    2014-08-01

    Full Text Available BACKGROUND: Manual small incision cataract surgery (SICS has given visual results almost equivalent to Phacoemulsification but limited studies are available regarding the efficacy of small incision cataract surgery in phaco suitable immature cataracts. OBJECTIVE: To compare manual small incision cataract surgery and Phacoemulsification in immature cataracts. MATERIALS AND METHODS: A single blind randomized controlled trial was conducted with 105 eyes each for small incision cataract surgery and Phacoemulsification. RESULT: Mean IOL power was similar in both Phacoemulsifications as well as SICS. Four cases of posterior capsular rupture occurred in Phacoemulsification while one case of zonular dialysis occurred in SICS. Uncorrected visual acuity was good (6/6-6/18 in 80.0 % of the phaco and 93.33 % of the SICS group. CONCLUSION: SICS surgical technique resulted in significantly better visual acuity on the 1st postoperative day in comparison with phaco. Hence, SICS with rigid PMMA IOL implantation being a cheaper, faster and easier technique, may be recommended for immature cataract surgery in the developing countries

  18. Cataract Surgery in Eyes with Shallow Anterior Chamber

    OpenAIRE

    Hüseyin Bayramlar; Remzi Karadağ; Ünsal Sarı

    2014-01-01

    Shallow anterior chamber may be encountered in an eye planned for cataract surgery as well as during phacoemulsification. In both situations, cataract surgery is a challenging case. In this article, we tried to review the situations and management of shallow anterior chamber in cataract surgery. (Turk J Ophthalmol 2014; 44: 388-91

  19. Cataract Surgery in Eyes with Shallow Anterior Chamber

    Directory of Open Access Journals (Sweden)

    Hüseyin Bayramlar

    2014-10-01

    Full Text Available Shallow anterior chamber may be encountered in an eye planned for cataract surgery as well as during phacoemulsification. In both situations, cataract surgery is a challenging case. In this article, we tried to review the situations and management of shallow anterior chamber in cataract surgery. (Turk J Ophthalmol 2014; 44: 388-91

  20. Acid phosphatase and lipid peroxidation in human cataractous lens epithelium

    Directory of Open Access Journals (Sweden)

    Vasavada Abhay

    1993-01-01

    Full Text Available The anterior lens epithelial cells undergo a variety of degenerative and proliferative changes during cataract formation. Acid phosphatase is primarily responsible for tissue regeneration and tissue repair. The lipid hydroperoxides that are obtained by lipid peroxidation of polysaturated or unsaturated fatty acids bring about deterioration of biological membranes at cellular and tissue levels. Acid phosphatase and lipid peroxidation activities were studied on the lens epithelial cells of nuclear cataract, posterior subcapsular cataract, mature cataract, and mixed cataract. Of these, mature cataractous lens epithelium showed maximum activity for acid phosphatase (516.83 moles of p-nitrophenol released/g lens epithelium and maximum levels of lipid peroxidation (86.29 O.D./min/g lens epithelium. In contrast, mixed cataractous lens epithelium showed minimum activity of acid phosphatase (222.61 moles of p-nitrophenol released/g lens epithelium and minimum levels of lipid peroxidation (54.23 O.D./min/g lens epithelium. From our study, we correlated the maximum activity of acid phosphatase in mature cataractous lens epithelium with the increased areas of superimposed cells associated with the formation of mature cataract. Likewise, the maximum levels of lipid peroxidation in mature cataractous lens epithelium was correlated with increased permeability of the plasma membrane. Conversely, the minimum levels of lipid peroxidation in mixed cataractous lens epithelium makes us presume that factors other than lipid peroxidation may also account for the formation of mixed type of cataract.

  1. Small incision cataract surgery: tips for avoiding surgical complications

    OpenAIRE

    Reeta Gurung; Albrecht Hennig

    2008-01-01

    Small incision cataract surgery (SICS) is one of the cataract surgical techniques commonly used in developing countries. This technique usually results in a good visual outcome and is useful for high-volume cataract surgery.1–3This article describes how to minimise surgical complications in SICS.

  2. Reduction of intraocular pressure and improvement of vision after cataract surgeries in angle closure glaucoma with concomitant cataract patients

    OpenAIRE

    Zhang, Zong-Mei; Niu, Qing; Nie, Yan; Zhang, Jin

    2015-01-01

    Objective: This study is to compare the efficacy of three different cataract surgeries in eyes with angle closure glaucoma (ACG) with concomitant cataract. Methods: A retrospective comparative analysis of 106 ACG patients (112 eyes) with concomitant cataract was conducted between February, 2012 and February, 2014. Clinical outcomes of ACG patients with concomitant cataract underwent phacoemulsification and intraocular lens implantation (group A, n = 34, 36 eyes, angle closure < 180°); combine...

  3. Coral bleaching under thermal stress: putative involvement of host/symbiont recognition mechanisms

    Directory of Open Access Journals (Sweden)

    Tambutte Sylvie

    2009-08-01

    Full Text Available Abstract Background Coral bleaching can be defined as the loss of symbiotic zooxanthellae and/or their photosynthetic pigments from their cnidarian host. This major disturbance of reef ecosystems is principally induced by increases in water temperature. Since the beginning of the 1980s and the onset of global climate change, this phenomenon has been occurring at increasing rates and scales, and with increasing severity. Several studies have been undertaken in the last few years to better understand the cellular and molecular mechanisms of coral bleaching but the jigsaw puzzle is far from being complete, especially concerning the early events leading to symbiosis breakdown. The aim of the present study was to find molecular actors involved early in the mechanism leading to symbiosis collapse. Results In our experimental procedure, one set of Pocillopora damicornis nubbins was subjected to a gradual increase of water temperature from 28°C to 32°C over 15 days. A second control set kept at constant temperature (28°C. The differentially expressed mRNA between the stressed states (sampled just before the onset of bleaching and the non stressed states (control were isolated by Suppression Subtractive Hybridization. Transcription rates of the most interesting genes (considering their putative function were quantified by Q-RT-PCR, which revealed a significant decrease in transcription of two candidates six days before bleaching. RACE-PCR experiments showed that one of them (PdC-Lectin contained a C-Type-Lectin domain specific for mannose. Immunolocalisation demonstrated that this host gene mediates molecular interactions between the host and the symbionts suggesting a putative role in zooxanthellae acquisition and/or sequestration. The second gene corresponds to a gene putatively involved in calcification processes (Pdcyst-rich. Its down-regulation could reflect a trade-off mechanism leading to the arrest of the mineralization process under stress

  4. Risk of retinal detachment following cataract extraction: results from the International Cataract Surgery Outcomes Study.

    OpenAIRE

    Norregaard, J. C.; Thoning, H.; Andersen, T. F.; Bernth-Petersen, P.; Javitt, J C; Anderson, G F

    1996-01-01

    AIMS: To estimate the risk of retinal detachment (RD) following cataract extraction in Denmark, and to compare the risk with that following cataract extraction in the USA, and with that in a sample of Danish patients who did not have ocular surgery. METHODS: A sample was created from the administrative Danish Hospital Register and included 19,252 patients who underwent first eye cataract surgery between 1985 and 1987, and who were 50 years of age or older. The patients were then followed for ...

  5. Molecular Mechanisms Involved in the Antitumor Activity of Cannabinoids on Gliomas: Role for Oxidative Stress

    International Nuclear Information System (INIS)

    Cannabinoids, the active components of Cannabis sativa, have been shown to exert antiproliferative and proapoptotic effects on a wide spectrum of tumor cells and tissues. Of interest, cannabinoids have displayed great potency in reducing the growth of glioma tumors, one of the most aggressive CNS tumors, either in vitro or in animal experimental models curbing the growth of xenografts generated by subcutaneous or intrathecal injection of glioma cells in immune-deficient mice. Cannabinoids appear to be selective antitumoral agents as they kill glioma cells without affecting the viability of non-transformed cells. This review will summarize the anti-cancer properties that cannabinoids exert on gliomas and discuss their potential action mechanisms that appear complex, involving modulation of multiple key cell signaling pathways and induction of oxidative stress in glioma cells

  6. Molecular Mechanisms Involved in the Antitumor Activity of Cannabinoids on Gliomas: Role for Oxidative Stress

    Energy Technology Data Exchange (ETDEWEB)

    Massi, Paola [Department of Pharmacology, Chemotherapy and Toxicology, University of Milan, Via Vanvitelli 32, 20129 Milan (Italy); Valenti, Marta; Solinas, Marta; Parolaro, Daniela, E-mail: daniela.parolaro@uninsubria.it [Department of Structural and Functional Biology, Section of Pharmacology, Center of Neuroscience, University of Insubria, Via A. da Giussano 10, 20152 Busto Arsizio, Varese (Italy)

    2010-05-26

    Cannabinoids, the active components of Cannabis sativa, have been shown to exert antiproliferative and proapoptotic effects on a wide spectrum of tumor cells and tissues. Of interest, cannabinoids have displayed great potency in reducing the growth of glioma tumors, one of the most aggressive CNS tumors, either in vitro or in animal experimental models curbing the growth of xenografts generated by subcutaneous or intrathecal injection of glioma cells in immune-deficient mice. Cannabinoids appear to be selective antitumoral agents as they kill glioma cells without affecting the viability of non-transformed cells. This review will summarize the anti-cancer properties that cannabinoids exert on gliomas and discuss their potential action mechanisms that appear complex, involving modulation of multiple key cell signaling pathways and induction of oxidative stress in glioma cells.

  7. Molecular Mechanisms Involved in the Antitumor Activity of Cannabinoids on Gliomas: Role for Oxidative Stress

    Directory of Open Access Journals (Sweden)

    Paola Massi

    2010-05-01

    Full Text Available Cannabinoids, the active components of Cannabis sativa, have been shown to exert antiproliferative and proapoptotic effects on a wide spectrum of tumor cells and tissues. Of interest, cannabinoids have displayed great potency in reducing the growth of glioma tumors, one of the most aggressive CNS tumors, either in vitro or in animal experimental models curbing the growth of xenografts generated by subcutaneous or intrathecal injection of glioma cells in immune-deficient mice. Cannabinoids appear to be selective antitumoral agents as they kill glioma cells without affecting the viability of non-transformed cells. This review will summarize the anti-cancer properties that cannabinoids exert on gliomas and discuss their potential action mechanisms that appear complex, involving modulation of multiple key cell signaling pathways and induction of oxidative stress in glioma cells.

  8. Dropped nucleus following phacoemulsification cataract surgery.

    Science.gov (United States)

    Tajunisah, I; Reddy, S C

    2007-12-01

    Twenty two cases of dropped nucleus following 1,196 phacoemulsification procedures in cataract surgery were examined retrospectively to determine the incidence, predisposing factors and visual outcomes of this dreaded complication. All the cases underwent pars plana vitrectomy and the lens fragments were removed with phacofragmotome, vitrectomy cutter or delivered through limbus. The incidence of dropped nucleus was 1.84%. The predisposing factors were hard cataracts (13.6%), polar cataracts (9.1%), previously vitrectomized eyes (4.5%) and high myopia (4.5%). The final visual outcome was > or = 6/12 in 10 eyes (45.5%); complications were seen in 5 eyes (22.7%). The interval between initial surgery and vitrectomy, the method of fragment removal and the type of lens implanted, did not influence the final visual outcome. PMID:18705466

  9. Clear corneal incision in cataract surgery

    Directory of Open Access Journals (Sweden)

    Ammar M Al Mahmood

    2014-01-01

    Full Text Available Since the introduction of sutureless clear corneal cataract incisions, the procedure has gained increasing popularity worldwide because it offers several advantages over the traditional sutured scleral tunnels and limbal incisions. Some of these benefits include lack of conjunctival trauma, less discomfort and bleeding, absence of suture-induced astigmatism, and faster visual rehabilitation. However, an increasing incidence of postoperative endophthalmitis after clear corneal cataract surgery has been reported. Different authors have shown a significant increase up to 15-fold in the incidence of endophthalmitis following clear corneal incision compared to scleral tunnels. The aim of this report is to review the advantages and disadvantages of clear corneal incisions in cataract surgery, emphasizing on wound construction recommendations based on published literature.

  10. [The development of cataract surgery after 1745].

    Science.gov (United States)

    Pouw, C A M Karin; Zegers, Richard H C

    2013-01-01

    Nowadays, cataract surgery is the most commonly performed surgical procedure in the Netherlands. This is due to the increasing incidence of cataracts, the changing indication for surgery in our society where good vision is becoming increasingly important, and the quality of the operation. How was this modern procedure developed? Cataracts were treated by couching until the middle of the 18th century. Since then, many discoveries by a number of doctors changed the procedure gradually from couching to lens extraction and through extracapsular to intracapsular extraction with the simultaneous implantation of an intraocular lens. This article outlines the development and also discusses some of the many inventions in the field of instrumentation and materials that have brought this intervention to its current high level; these include the cryo-probe, implantation of artificial lenses, the use of hyaluronic acid, phaco-emulsification, smaller incisions without sutures and the development of foldable intraocular lenses. PMID:23548190

  11. Association between a Tetranucleotide Repeat Polymorphism of SPAG16 Gene and Cataract in Male Children

    Directory of Open Access Journals (Sweden)

    Shipra Mehra

    2013-01-01

    Full Text Available Purpose. Studies involving genotyping of STR markers at 2q34 have repeatedly found the region to host the disease haplotype for pediatric cataract. Present study investigated the association of D2S2944 marker, in sperm associated antigen 16 (SPAG16 gene and rs2289917 polymorphism, in γ-crystallin B gene, with childhood cataract. Methods. 97 pediatric cataract cases and 110 children with no ocular defects were examined for tetranucleotide repeat marker/SNP using PCR-SSLP/RFLP techniques. Polymorphisms were assessed for association using contingency tables and linkage disequilibrium among alleles of the markers was estimated. Energy-optimization program predicted the secondary structure models of repeats of D2S2944. Results. Seven alleles of D2S2944, with 9–15 “GATA” repeats, were observed. Frequency of the longer allele of D2S2944, ≥(GATA13 repeats, was 0.73 in cases and 0.56 in controls (P=0.0123. Male children bearing ≥(GATA13 repeats showed >3-fold higher risk for cataract (CI95% = 1.43–7.00, P=0.0043, Pc=0.0086 as compared to female children (OR=1.19, CI95% = 0.49–2.92, P=0.70. Cases with haplotype—≥(GATA13 of D2S2944 and “C” allele rs2289917—have a higher risk for pediatric cataract (OR=2.952, CI95% = 1.595~5.463, P=0.000453. >(GATA13 repeats formed energetically more favorable stem-loop structure. Conclusion. Intragenic microsatellite repeat expansion in SPAG16 gene increases predisposition to pediatric cataract by probably interfering posttranscriptional events and affecting the expression of adjacent lens transparency gene/s in a gender bias manner.

  12. A case of primary spinal myoclonus: clinical presentation and possible mechanisms involved

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    Campos Cynthia Resende

    2003-01-01

    Full Text Available Spinal myoclonus is a rare movement disorder characterized by myoclonic involvement of a group of muscles supplied by a few contiguous segments of the spinal cord. Structural lesions are usually the cause, but in primary spinal myoclonus the etiology remains unknown. We present the case of a 26-year-old woman with cervical spinal myoclonus in which both clinical and electromyographic findings pointed to the segment C1-C3 as the origin of the myoclonus. Laboratorial examinations were normal and no structural lesion was found in magnetic resonance imaging (MRI. Botulinum toxin type A was injected in infrahyoid muscles and cervical paraspinal musculature. The patient remained free of symptoms for almost five months. The pathophysiology of spinal myoclonus remains speculative, but there is evidence that various possible mechanisms can be involved: loss of inhibitory function of local dorsal horn interneurons, abnormal hyperactivity of local anterior horn neurons, aberrant local axons re-excitations and loss of inhibition from suprasegmentar descending pathways.

  13. Effect of diet and fenfluramine on thermogenesis in the rat: possible involvement of serotonergic mechanisms.

    Science.gov (United States)

    Rothwell, N J; Stock, M J

    1987-01-01

    A single injection of 5-hydroxytryptamine (5HT, 1 mg/kg, s.c.) in rats stimulated resting oxygen consumption (Vo2) by 21 percent; this was reduced (to 8 percent) by pretreatment with hexamethonium (5 mg/kg, s.c.). DL-fenfluramine injection (20 mg/kg, s.c.) stimulated metabolic rate (Vo2) by about 40 percent, but caused only 11 and 15 per cent increases in animals pretreated with hexamethonium or metergoline (5 mg/kg, s.c.), respectively. Interscapular brown adipose tissue (BAT) activity, assessed from mitochondrial GDP-binding, was increased by 96 per cent in intact tissue 1 h after fenfluramine injection; this response was completely prevented by surgical sympathectomy of interscapular BAT. Metergoline significantly inhibited (by 46 percent) the acute thermic response (postprandial rise in Vo2) to a 40-kJ meal in normal rats, and depressed resting Vo2 in protein-deficient rats by 18 percent, but did not affect resting Vo2 in control animals. BAT activity (mitochondrial GDP-binding) was elevated by 56 per cent in rats fed the low-protein diet, but this difference was almost completely abolished by prior treatment with metergoline. These data demonstrate a potent thermogenic effect of fenfluramine which apparently involves serotonergic pathways and activation of sympathetic outflow to BAT, and indicate that acute thermic responses to food and chronic thermogenic responses to low-protein diets may also involve serotonergic mechanisms. PMID:3667065

  14. [The denominations cataract and glaucoma].

    Science.gov (United States)

    Tornquist, R

    1997-01-01

    Since ancient times a grey or white pupil in an nearly blind eye was thought to be caused by a mucous substance in front of the lens. It was called "hypochysis" or "hypochyma" in Greece and "suffusio" in Rome. Later the term "cataract" (=waterfall) was the most popular denomination. A surgical method was tried very early with usually good effect, when with a thin needle, introduced into the eye, the opaque material was removed from the pupillary area. In the middle of the 17th century more careful investigations showed that there was no membrane in front of the lens, but the lens itself was opaque. The final proof was delivered when an extraction of the lens was performed with good effect. In ancient times incurable blindness, which was called glaucoma, was thought to be located to the lens, which probably had a very important role in the seeing process. The name (of Greek orgin) is translated "green" or "blue-green", which was sometimes notified to be the color of the lens, seen through the pupil, in these cases. A period of great confusion followed when the removal of this very important part of the eye did not lead to blindness but rather an improved vision. As there were significant difficulties in identifying the specific color of the pupil the name glaucoma seemed to be very inadequate. In the beginning of the 19th century a disease entity (which is to-day called acute closed-angle glaucoma) seemed to eventually fullfill the demand of a greenlooking pupil. The most characteristic symptoms are pain and a high intraocular pressure causing a corneal edema and a change of the blackness of the pupil to hazy grey (and maybe a little green?). PMID:11625470

  15. Cataract: refractive error, diabetes, and morphology.

    OpenAIRE

    Perkins, E. S.

    1984-01-01

    A retrospective analysis of 388 records of patients undergoing surgery for cataract between the years 1968 and 1978 showed that more women than men were admitted. About 13.7% of the patients were diabetic, and there was a striking excess of women over men with diabetes and cataract. The diabetic patients required surgery at an earlier age than the non-diabetics. Patients who had been refracted at least 5 years before surgery showed an incidence of myopia of -1.00 D or more of 25.4%. In 34% of...

  16. Sensory exotropia subsequent to senile cataract

    Institute of Scientific and Technical Information of China (English)

    LOU Ding-hua; XU Ye-sheng; LI Yu-min

    2005-01-01

    To evaluate the phacoemulsification and intraocular lens implantation in patients with sensory exotropia subsequent to senile cataract. The authors prospectively studied the role of phacoemulsification and intraocular lens implantation on 25 patients by observing visual acuity, ocular alignment, binocular vision and diplopia pre-, 1 month post- and 3 months post-operation. The patients underwent follow-up for three months. Postoperatively, one patient had a corrected visual acuity of 20/50, and 24 patients had 20/40 or better. The ocular alignment, binocular vision and diplopia were resolved spontaneously. Phacoemulsification and intraocular lens implantation performed together is effective on sensory exotropia subsequent to senile cataract.

  17. Outsourced cataract surgery and postoperative endophthalmitis

    DEFF Research Database (Denmark)

    Solborg Bjerrum, Søren; Kiilgaard, Jens F; Mikkelsen, Kim Lyngby; la Cour, Morten

    2013-01-01

    To compare the risk of postoperative endophthalmitis (PE) after cataract surgery at eye departments in public hospitals and private hospitals/eye clinics and to evaluate if the Danish National Patient Registry (NPR) is a reliable database to monitor the PE risk.......To compare the risk of postoperative endophthalmitis (PE) after cataract surgery at eye departments in public hospitals and private hospitals/eye clinics and to evaluate if the Danish National Patient Registry (NPR) is a reliable database to monitor the PE risk....

  18. Partially coherent interferometric biometry in cataract surgery

    Science.gov (United States)

    Drexler, Wolfgang; Findl, Oliver; Menapace, Rupert; Hitzenberger, Christoph K.; Fercher, Adolf F.

    1999-02-01

    In an earlier study we showed that precise axial eye length measurement on cataract eyes is possible with the dual beam partial coherence interferometry technique (PCI). A high correlation with the standard ultrasound technique has been obtained. Recently, in a prospective study, partially coherent interferometry and ultrasound biometry were compared in cataract surgery using the SRK II formula based on US applanation biometry. Three months after surgery PCI was repeated and refractive outcome was determined. The use of PCI would have improved refractive outcome by about 30%.

  19. Prevalence and aetiology of cataract in Punjab.

    OpenAIRE

    Chatterjee, A.; Milton, R C; Thyle, S

    1982-01-01

    Three districts in the Punjab plains were surveyed in 1976-7 for senile cataract and potential risk factors. The prevalence of senile cataract was 15.3% among 1269 persons examined who were aged 30 ang older, and 4.3% for all ages. These figures confirmed previous reports of high prevalence. The prevalence was 1% for ages 30-49 and increased markedly in the sixth and seventh decades to 67% for ages 70 and older. Univariate age-adjusted analyses of selected socioeconomic, demographic, dietary,...

  20. MANUAL SMALL INCISION CATARACT SURGERY (MSICS

    Directory of Open Access Journals (Sweden)

    Mishra

    2014-09-01

    Full Text Available : In developing country like India, the primary goal is to provide all the benefits to common man at minimal possible cost in visual rehabilitation of cataract. In achieving this goal, the surgery (MICS described in this article can be extremely helpful. It has almost all the advantages of phacoemulsification, at the same time it is inexpensive. The wound construction, various techniques of nucleus delivery in MSICS are described precisely. This may stimulate the reader towards this surgery, which is the only way to tackle the huge backlog of cataract in developing countries, particularly in India, where 60% of rural people live in less than thirty rupees a day.

  1. Cardiac involvement in proximal myotonic myopathy

    OpenAIRE

    von zur Muhlen, F; Klass, C; Kreuzer, H.; Mall, G; Giese, A.; Reimers, C

    1998-01-01

    Proximal myotonic myopathy (PROMM) is a recently described autosomal dominantly inherited disorder resulting in proximal muscle weakness, myotonia, and cataracts. A few patients with cardiac involvement (sinus bradycardia, supraventricular bigeminy, conduction abnormalities) have been reported. The cases of three relatives with PROMM (weakness of neck flexors and proximal extremity muscles, calf hypertrophy, myotonia, cataracts) are reported: a 54 year old man, his 73 year old mother, and 66 ...

  2. Mechanisms involved in ceramide-induced cell cycle arrest in human hepatocarcinoma cells

    Institute of Scientific and Technical Information of China (English)

    Jing Wang; Xiao-Wen Lv; Jie-Ping Shi; Xiao-Song Hu

    2007-01-01

    AIM:To investigate the effect of ceramide on the cell cycle in human hepatocarcinoma Bel7402 cells.Possible molecular mechanisms were explored.METHODS:[3-(4,5)-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide(MTT)assay,plasmid transfection,reporter assay,FACS and Western blotting analyses were employed to investigate the effect and the related molecular mechanisms of C2-ceramide on the cell cycle of Bel7402 cells.RESULTS:C2-ceramide was found to inhibit the growth of Bel7402 cells by inducing cell cycle arrest.During the process,the expression of p21 protein increased,while that of cyclinD1,phospho-ERK1/2 and c-myc decreased.Furthermore,the level of CDK7 was downregulated,while the transcriptional activity of PPARγ was upregulated.Addition of GW9662,which is a PPARγ specific antagonist,could reserve the modulation action on CDK7.CONCLUSION:Our results support the hypothesis that cell cycle arrest induced by C2-ceramide may be mediated via accumulation of p21 and reduction of cyclinD1 and CDK7,at least partly,through PPARγ activation.The ERK signaling pathway was involved in this process.

  3. Molecular mechanisms of heptaplatin effective against cisplatin-resistant cancer cell lines: less involvement of metallothionein

    Directory of Open Access Journals (Sweden)

    Moon Sung-Pyo

    2004-10-01

    Full Text Available Abstract Background Heptaplatin is a new platinum derivative with anticancer activity against various cancer cell lines, including cisplatin-resistant cancer cell lines (Cancer Chemother Pharmacol 1995; 35: 441. Methods Molecular mechanisms of heptaplatin effective against cisplatin-resistant cancer cell lines has been investigated in connection with metallothionein (MT. Cytotoxicity was determined by an MTT assay. MT mRNA, was determined by RT-PCR assay. Transfection study was carried out to examine the function of MT. Results Of various gastric cancer cell lines, SNU-638 and SNU-601 showed the highest and lowest levels of MT mRNA, respectively, showing 80-fold difference. The IC50 values of SNU-638 to cisplatin, carboplatin and heptaplatin were 11.2-fold, 5.1-fold and 2.0-fold greater than those of SNU-601, respectively. Heptaplatin was more effective against cisplatin-resistant and MT-transfected gastric cancer sublines than cisplatin or carboplatin was. In addition, heptaplatin attenuated cadmium, but not zinc, induction of MT. Conclusion These results indicate that molecular mechanisms of heptaplatin effective against cisplatin-resistant gastric cancer sublines is at least in part due to the less involvement of MT in heptaplatin resistance as well as its attenuation of MT induction.

  4. A role of nitric oxide mechanism involved in the protective effects of venlafaxine in sleep deprivation.

    Science.gov (United States)

    Kumar, Anil; Garg, Ruchika

    2008-12-12

    The present study was designed to explore the possible nitric oxide mechanism in protective effect of venlafaxine in sleep deprivation in mice. Laca mice were sleep deprived for period of 72 h using grid suspended over water method. Venlafaxine (2.5, 5 and 10mg/kg, ip), l-arginine (50mg/kg, ip), l-NAME (10mg/kg, ip) and methylene blue (10mg/kg, ip) were administered for 5 days, starting 2 days before 72-h sleep deprivation. Various behavioral tests (plus maze, zero maze, mirror chamber tests for anxiety, and actophotometer test) followed by oxidative stress parameters (malondialdehyde level, glutathione, catalase, nitrite and protein) were assessed. The present study showed that venlafaxine (5 and 10mg/kg, ip) drug treatment significantly reversed 72-h sleep deprivation caused anxiety like behavior, impairment in locomotor activity and oxidative damage (increased lipid peroxidation and nitrite levels and depleted reduced glutathione and catalase activity) as compared to control. l-NAME (10mg/kg) and methylene blue (10mg/kg) pretreatment with lower dose of venlafaxine (5mg/kg) potentiated the protective effect of venlafaxine (5mg/kg). However, l-arginine (50mg/kg) pretreatment with venlafaxine (5mg/kg) reversed the protective effect of venlafaxine. Results of present study suggest that nitric oxide mechanism is involved in the protective effect of venlafaxine against sleep-deprivation-induced behavior alteration and oxidative damage in mice. PMID:18674568

  5. Depletion of bovine pituitary prolactin by cysteamine involves a thiol:disulfide mechanism

    International Nuclear Information System (INIS)

    Cysteamine [2-aminoethanethiol (CySH)] reduces measurable PRL concentrations in vivo and in vitro. Since secretion is also inhibited, CySH may block conversion from a poorly assayable hormone storage form(s) to readily assayable, releasable PRL. This would represent a previously unrecognized mechanism for secretory regulation. We undertook the present study to identify the sites involved in the loss of measurable PRL (depletion) induced by cysteamine. The disulfide cystamine was ineffective on secretory granules unless combined with reduced glutathione, indicating the generation of the active CySH-thiol form. Pretreatment of granules with thiol-blocking agents resulted in dose-dependent enhancement of CySH inhibition, achieving nearly complete inhibition with 5 mM iodoacetamide. In contrast, pretreatment with reduced glutathione or dithiothreitol, respectively, impaired or abolished the CySH effect. These data suggest that the mechanism by which CySH causes PRL depletion is mediated by granule disulfides and the -SH of CySH. The regulation of thiol:disulfide equilibria appears to be an important determinant of the detectability of PRL storage forms and of their secretion

  6. A host defense mechanism involving CFTR-mediated bicarbonate secretion in bacterial prostatitis.

    Directory of Open Access Journals (Sweden)

    Chen Xie

    Full Text Available BACKGROUND: Prostatitis is associated with a characteristic increase in prostatic fluid pH; however, the underlying mechanism and its physiological significance have not been elucidated. METHODOLOGY/PRINCIPAL FINDINGS: In this study a primary culture of rat prostatic epithelial cells and a rat prostatitis model were used. Here we reported the involvement of CFTR, a cAMP-activated anion channel conducting both Cl(- and HCO(3(-, in mediating prostate HCO(3(- secretion and its possible role in bacterial killing. Upon Escherichia coli (E. coli-LPS challenge, the expression of CFTR and carbonic anhydrase II (CA II, along with several pro-inflammatory cytokines was up-regulated in the primary culture of rat prostate epithelial cells. Inhibiting CFTR function in vitro or in vivo resulted in reduced bacterial killing by prostate epithelial cells or the prostate. High HCO(3(- content (>50 mM, rather than alkaline pH, was found to be responsible for bacterial killing. The direct action of HCO(3(- on bacterial killing was confirmed by its ability to increase cAMP production and suppress bacterial initiation factors in E. coli. The relevance of the CFTR-mediated HCO(3(- secretion in humans was demonstrated by the upregulated expression of CFTR and CAII in human prostatitis tissues. CONCLUSIONS/SIGNIFICANCE: The CFTR and its mediated HCO(3(- secretion may be up-regulated in prostatitis as a host defense mechanism.

  7. A non-cardiomyocyte autonomous mechanism of cardioprotection involving the SLO1 BK channel

    Directory of Open Access Journals (Sweden)

    Andrew P. Wojtovich

    2013-03-01

    Full Text Available Opening of BK-type Ca2+ activated K+ channels protects the heart against ischemia-reperfusion (IR injury. However, the location of BK channels responsible for cardioprotection is debated. Herein we confirmed that openers of the SLO1 BK channel, NS1619 and NS11021, were protective in a mouse perfused heart model of IR injury. As anticipated, deletion of the Slo1 gene blocked this protection. However, in an isolated cardiomyocyte model of IR injury, protection by NS1619 and NS11021 was insensitive to Slo1 deletion. These data suggest that protection in intact hearts occurs by a non-cardiomyocyte autonomous, SLO1-dependent, mechanism. In this regard, an in-situ assay of intrinsic cardiac neuronal function (tachycardic response to nicotine revealed that NS1619 preserved cardiac neurons following IR injury. Furthermore, blockade of synaptic transmission by hexamethonium suppressed cardioprotection by NS1619 in intact hearts. These results suggest that opening SLO1 protects the heart during IR injury, via a mechanism that involves intrinsic cardiac neurons. Cardiac neuronal ion channels may be useful therapeutic targets for eliciting cardioprotection.

  8. High-fidelity cataract surgery simulation and third world blindness.

    Science.gov (United States)

    Singh, Ajay; Strauss, Glenn H

    2015-04-01

    The burden of global cataract blindness continues to rise, because the number of surgical ophthalmologists is insufficient, and they are unevenly distributed. There is an urgent need to train surgeons quickly and comprehensively in high-quality, low-cost cataract removal techniques. The authors suggest manual small-incision cataract surgery as a safe alternative to phacoemulsification cataract surgery in the developing world. They discuss the development of a novel, full-immersion, physics-based surgical training simulator as the centerpiece of a scalable, comprehensive training system for manual small-incision cataract surgery. PMID:24996918

  9. [Objective evaluation the application of femtosecond laser in cataract surgery].

    Science.gov (United States)

    Liu, Y Z

    2016-02-11

    Femtosecond laser-assisted cataract surgery (FLACS) is a novel technology and the biggest revolution in the field of cataract in the latest several years. However, increasing large-scale population randomized controlled trials (RCT) have demonstrated that FLACS does not provide significant advantages over conventional phacoemulsification cataract surgery (CPCS) for common cataract patients. Furthermore, the cost and space requirement of the femtosecond equipment are another two limitations for the universal application of FSL in cataract surgery. However, FLACS may be beneficial for complex cataract situations, such as lens dislocation, zonular laxity, traumatic cataract, low preoperative endothelial cell values, and significant corneal astigmatism. With the progress of science and technology, FLACS can be expected to achieve integration with phacoemulsification systems, and equipment costs can be reduced, making it more widely used in clinical practice in the future. (Chin J Ophthalmol, 2016, 52: 81-84). PMID:26906700

  10. Do patients with age related maculopathy and cataract benefit from cataract surgery?

    OpenAIRE

    Shuttleworth, G.; Luhishi, E; Harrad, R

    1998-01-01

    AIMS—To assess the benefits of cataract extraction in patients with age related maculopathy (ARM).
METHODS—1073 randomly selected cataract operations were reviewed and 99 cases of preoperatively recognised ARM were identified for investigation. Data relating to visual function were retrieved from case notes, and patient responses to a questionnaire were analysed.
RESULTS—98% had dry or unspecified ARM. Only 2% had exudative maculopathy. 81% of cases had an improvement in best distance acuity;...

  11. Sutureless Non-phaco Cataract Surgery: A Solution to Reduce Worldwide Cataract Blindness?

    OpenAIRE

    Albrecht Hennig

    2003-01-01

    The Search for Appropriate Sutureless Cataract Surgery. During the last decade, in industrialised countries phacoemulsification has largely replaced ab-externo extracapsular cataract extraction with posterior chamber intraocular lenses (ECCE/PC IOL) with sutures. The small self-sealing phaco incision provides rapid visual rehabilitation, and the surgery is increasingly done on an outpatient basis. However, in developing countries phacoemulsification is performed only on selected patients, usu...

  12. Involvement of medullary GABAergic system in extraterritorial neuropathic pain mechanisms associated with inferior alveolar nerve transection.

    Science.gov (United States)

    Okada-Ogawa, Akiko; Nakaya, Yuka; Imamura, Yoshiki; Kobayashi, Masayuki; Shinoda, Masamichi; Kita, Kozue; Sessle, Barry J; Iwata, Koichi

    2015-05-01

    In order to determine if the functional changes in the GABAergic system in the trigeminal spinal subnucleus caudalis (Vc) are involved in the mechanisms underlying extraterritorial neuropathic pain in the orofacial region following inferior alveolar nerve transection (IANX), mechanical noxious behavior, phosphorylated extracellular signal-regulated kinase (pERK) immunohistochemistry and single neuronal activity were analyzed in vesicular GABA transporter (VGAT)-VenusA rats expressing fluorescent protein and the VGAT in Vc neurons. The number of VGAT-VenusA positive neurons was significantly reduced in IANX rats than naive and sham rats at 7days after nerve transection. The number of VGAT-VenusA positive pERK-immunoreactive (IR) cells was significantly increased in IANX rats at 21days after IAN transection compared with naive and sham rats. The background activity and mechanical-evoked responses of Vc nociceptive neurons were significantly depressed after intrathecal application of the GABA receptor agonist muscimol in sham rats but not in IANX rats. Furthermore, the expression of potassium-chloride co-transporter 2 (KCC2) in the Vc was significantly reduced in IANX rats compared with sham rats. The head-withdrawal threshold (HWT) to mechanical stimulation of the whisker pad skin was significantly decreased in IANX rats compared with sham rats on days 7 and 21 after IANX. The significant reduction of the HWT and significant increase in the number of VGAT-VenusA negative pERK-IR cells were observed in KCC2 blocker R-DIOA-injected rats compared with vehicle-injected rats on day 21 after sham treatment. These findings revealed that GABAergic Vc neurons might be reduced in their number at the early period after IANX and the functional changes might occur in GABAergic neurons from inhibitory to excitatory at the late period after IANX, suggesting that the neuroplastic changes occur in the GABAergic neuronal network in the Vc due to morphological and functional changes at

  13. Cataract-free interval and severity of cataract after total body irradiation and bone marrow transplantation: influence of treatment parameters

    International Nuclear Information System (INIS)

    Purpose: To determine prospectively the cataract-free interval (latency time) after total body irradiation (TBI) and bone marrow transplantation (BMT) and to assess accurately the final severity of the cataract. Methods and Materials: Ninety-three of the patients who received TBI as a part of their conditioning regimen for BMT between 1982 and 1995 were followed with respect to cataract formation. Included were only patients who had a follow-up period of at least 23 months. TBI was applied in one fraction of 8 Gy or two fractions of 5 or 6 Gy. Cataract-free period was assessed and in 56 patients, who could be followed until stabilization of the cataract had occurred, final severity of the cataract was determined using a classification system. With respect to final severity, two groups were analyzed: subclinical low-grade cataract and high-grade cataract. Cataract-free period and final severity were determined with respect to type of transplantation, TBI dose, and posttransplant variables such as graft versus host disease (GVHD) and steroid treatment. Results: Cataract incidence of the analyzed patients was 89%. Median time to develop a cataract was 58 months for autologous transplanted patients. For allogeneic transplanted patients treated or not treated with steroids, median times were 33 and 46 months, respectively. Final severity was not significantly different for autologous or allogeneic patients. In allogeneic patients, however, final severity was significantly different for patients who had or had not been treated with steroids for GVHD: 93% versus 35% high-grade cataract, respectively. Final severity was also different for patients receiving 1 x 8 or 2 x 5 Gy TBI, from patients receiving 2 x 6 Gy as conditioning therapy: 33% versus 79% high-grade cataract, respectively. The group of patients receiving 2 x 6 Gy comprised, however, more patients with steroid treatment for GVHD. So the high percentage of high-grade cataract in the 2 x 6 Gy group might also

  14. Development of neurodevelopmental disorders: a regulatory mechanism involving bromodomain-containing proteins

    Directory of Open Access Journals (Sweden)

    Li Junlin

    2013-02-01

    Full Text Available Abstract Neurodevelopmental disorders are classified as diseases that cause abnormal functions of the brain or central nervous system. Children with neurodevelopmental disorders show impaired language and speech abilities, learning and memory damage, and poor motor skills. However, we still know very little about the molecular etiology of these disorders. Recent evidence implicates the bromodomain-containing proteins (BCPs in the initiation and development of neurodevelopmental disorders. BCPs have a particular domain, the bromodomain (Brd, which was originally identified as specifically binding acetyl-lysine residues at the N-terminus of histone proteins in vitro and in vivo. Other domains of BCPs are responsible for binding partner proteins to form regulatory complexes. Once these complexes are assembled, BCPs alter chromosomal states and regulate gene expression. Some BCP complexes bind nucleosomes, are involved in basal transcription regulation, and influence the transcription of many genes. However, most BCPs are involved in targeting. For example, some BCPs function as a recruitment platform or scaffold through their Brds-binding targeting sites. Others are recruited to form a complex to bind the targeting sites of their partners. The regulation mediated by these proteins is especially critical during normal and abnormal development. Mutant BCPs or dysfunctional BCP-containing complexes are implicated in the initiation and development of neurodevelopmental disorders. However, the pathogenic molecular mechanisms are not fully understood. In this review, we focus on the roles of regulatory BCPs associated with neurodevelopmental disorders, including mental retardation, Fragile X syndrome (FRX, Williams syndrome (WS, Rett syndrome and Rubinstein-Taybi syndrome (RTS. A better understanding of the molecular pathogenesis, based upon the roles of BCPs, will lead to screening of targets for the treatment of neurodevelopmental disorders.

  15. Development of neurodevelopmental disorders: a regulatory mechanism involving bromodomain-containing proteins.

    Science.gov (United States)

    Li, Junlin; Zhao, Guifang; Gao, Xiaocai

    2013-01-01

    Neurodevelopmental disorders are classified as diseases that cause abnormal functions of the brain or central nervous system. Children with neurodevelopmental disorders show impaired language and speech abilities, learning and memory damage, and poor motor skills. However, we still know very little about the molecular etiology of these disorders. Recent evidence implicates the bromodomain-containing proteins (BCPs) in the initiation and development of neurodevelopmental disorders. BCPs have a particular domain, the bromodomain (Brd), which was originally identified as specifically binding acetyl-lysine residues at the N-terminus of histone proteins in vitro and in vivo. Other domains of BCPs are responsible for binding partner proteins to form regulatory complexes. Once these complexes are assembled, BCPs alter chromosomal states and regulate gene expression. Some BCP complexes bind nucleosomes, are involved in basal transcription regulation, and influence the transcription of many genes. However, most BCPs are involved in targeting. For example, some BCPs function as a recruitment platform or scaffold through their Brds-binding targeting sites. Others are recruited to form a complex to bind the targeting sites of their partners. The regulation mediated by these proteins is especially critical during normal and abnormal development. Mutant BCPs or dysfunctional BCP-containing complexes are implicated in the initiation and development of neurodevelopmental disorders. However, the pathogenic molecular mechanisms are not fully understood. In this review, we focus on the roles of regulatory BCPs associated with neurodevelopmental disorders, including mental retardation, Fragile X syndrome (FRX), Williams syndrome (WS), Rett syndrome and Rubinstein-Taybi syndrome (RTS). A better understanding of the molecular pathogenesis, based upon the roles of BCPs, will lead to screening of targets for the treatment of neurodevelopmental disorders. PMID:23425632

  16. Mechanisms involved in calcium oxalate endocytosis by Madin-Darby canine kidney cells

    Directory of Open Access Journals (Sweden)

    A.H. Campos

    2000-01-01

    Full Text Available Calcium oxalate (CaOx crystals adhere to and are internalized by tubular renal cells and it seems that this interaction is related (positively or negatively to the appearance of urinary calculi. The present study analyzes a series of mechanisms possibly involved in CaOx uptake by Madin-Darby canine kidney (MDCK cells. CaOx crystals were added to MDCK cell cultures and endocytosis was evaluated by polarized light microscopy. This process was inhibited by an increase in intracellular calcium by means of ionomycin (100 nM; N = 6; 43.9% inhibition; P<0.001 or thapsigargin (1 µM; N = 6; 33.3% inhibition; P<0.005 administration, and via blockade of cytoskeleton assembly by the addition of colchicine (10 µM; N = 8; 46.1% inhibition; P<0.001 or cytochalasin B (10 µM; N = 8; 34.2% inhibition; P<0.001. Furthermore, CaOx uptake was reduced when the activity of protein kinase C was inhibited by staurosporine (10 nM; N = 6; 44% inhibition; P<0.01, or that of cyclo-oxygenase by indomethacin (3 µM; N = 12; 17.2% inhibition; P<0.05; however, the uptake was unaffected by modulation of potassium channel activity with glibenclamide (3 µM; N = 6, tetraethylammonium (1 mM; N = 6 or cromakalim (1 µM; N = 6. Taken together, these data indicate that the process of CaOx internalization by renal tubular cells is similar to the endocytosis reported for other systems. These findings may be relevant to cellular phenomena involved in early stages of the formation of renal stones.

  17. Cost-effectiveness analysis of cataract surgery with intraocular lens implantation: extracapsular cataract extraction versus phacoemulsification

    Directory of Open Access Journals (Sweden)

    Mohd R.A. Manaf

    2007-03-01

    Full Text Available A randomized single blinded clinical trial to compare the cost-effectiveness of cataract surgery between extracapsular cataract extraction (ECCE and phacoemulsification (PEA was conducted at Hospital Universiti Kebangsaan Malaysia (HUKM from March 2000 until August 2001. The cost of a cataract surgery incurred by hospital, patients and households were calculated preoperatively, one week, two months (for both techniques and six months (for ECCE only. Effectiveness of cataract surgery was assessed using Visual Function 14 (VF-14, quality of life measurement specifically for vision. The cost analysis results from each 50 subjects of ECCE and PEA group showed that average cost for one ECCE after six months post-operation is USD 458 (± USD 72 and for PEA is USD 528 (± USD 125. VF-14 score showed a significant increased after a week, two months and six months post-operation compared to the score before operation for both techniques (p<0.001. However, there was no significant difference between them (p = 0.225. This study indicated that ECCE is more cost effective compared to PEA with cost per one unit increment of VF-14 score of USD 14 compared to USD 20 for PEA. (Med J Indones 2007; 16:25-31 Keywords: cataract, cost-effectiveness, extracapsular cataract extraction, phacoemulsification, visual function 14

  18. Multiple mechanisms involved in diabetes protection by lipopolysaccharide in non-obese diabetic mice

    International Nuclear Information System (INIS)

    Toll-like receptor 4 (TLR4) activation has been proposed to be important for islet cell inflammation and eventually β cell loss in the course of type 1 diabetes (T1D) development. However, according to the “hygiene hypothesis”, bacterial endotoxin lipopolysaccharide (LPS), an agonist on TLR4, inhibits T1D progression. Here we investigated possible mechanisms for the protective effect of LPS on T1D development in non-obese diabetic (NOD) mice. We found that LPS administration to NOD mice during the prediabetic state neither prevented nor reversed insulitis, but delayed the onset and decreased the incidence of diabetes, and that a multiple-injection protocol is more effective than a single LPS intervention. Further, LPS administration suppressed spleen T lymphocyte proliferation, increased the generation of CD4+CD25+Foxp3+ regulatory T cells (Tregs), reduced the synthesis of strong Th1 proinflammatory cytokines, and downregulated TLR4 and its downstream MyD88-dependent signaling pathway. Most importantly, multiple injections of LPS induced a potential tolerogenic dendritic cell (DC) subset with low TLR4 expression without influencing the DC phenotype. Explanting DCs from repeated LPS-treated NOD mice into NOD/SCID diabetic mice conferred sustained protective effects against the progression of diabetes in the recipients. Overall, these results suggest that multiple mechanisms are involved in the protective effects of LPS against the development of diabetes in NOD diabetic mice. These include Treg induction, down-regulation of TLR4 and its downstream MyD88-dependent signaling pathway, and the emergence of a potential tolerogenic DC subset. - Highlights: • Administration of lipopolysaccharide (LPS) prevented type 1 diabetes in NOD mice. • Downregulating TLR4 level and MyD88-dependent pathway contributed to protection of LPS. • LPS administration also hampered DC maturation and promoted Treg differentiation

  19. Multiple mechanisms involved in diabetes protection by lipopolysaccharide in non-obese diabetic mice

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Jun [Department of Pharmacology, School of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology, Wuhan (China); Department of Pharmacology, College of Medicine, Wuhan University of Science and Technology, Wuhan (China); Cao, Hui [Department of Pharmacology, School of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology, Wuhan (China); Wang, Hongjie [Section of Neurobiology, Torrey Pines Institute for Molecular Studies, Port Saint Lucie, FL (United States); Yin, Guoxiao; Du, Jiao; Xia, Fei; Lu, Jingli [Department of Pharmacology, School of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology, Wuhan (China); Xiang, Ming, E-mail: xiangming@mails.tjmu.edu.cn [Department of Pharmacology, School of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology, Wuhan (China)

    2015-06-15

    Toll-like receptor 4 (TLR4) activation has been proposed to be important for islet cell inflammation and eventually β cell loss in the course of type 1 diabetes (T1D) development. However, according to the “hygiene hypothesis”, bacterial endotoxin lipopolysaccharide (LPS), an agonist on TLR4, inhibits T1D progression. Here we investigated possible mechanisms for the protective effect of LPS on T1D development in non-obese diabetic (NOD) mice. We found that LPS administration to NOD mice during the prediabetic state neither prevented nor reversed insulitis, but delayed the onset and decreased the incidence of diabetes, and that a multiple-injection protocol is more effective than a single LPS intervention. Further, LPS administration suppressed spleen T lymphocyte proliferation, increased the generation of CD4{sup +}CD25{sup +}Foxp3{sup +} regulatory T cells (Tregs), reduced the synthesis of strong Th1 proinflammatory cytokines, and downregulated TLR4 and its downstream MyD88-dependent signaling pathway. Most importantly, multiple injections of LPS induced a potential tolerogenic dendritic cell (DC) subset with low TLR4 expression without influencing the DC phenotype. Explanting DCs from repeated LPS-treated NOD mice into NOD/SCID diabetic mice conferred sustained protective effects against the progression of diabetes in the recipients. Overall, these results suggest that multiple mechanisms are involved in the protective effects of LPS against the development of diabetes in NOD diabetic mice. These include Treg induction, down-regulation of TLR4 and its downstream MyD88-dependent signaling pathway, and the emergence of a potential tolerogenic DC subset. - Highlights: • Administration of lipopolysaccharide (LPS) prevented type 1 diabetes in NOD mice. • Downregulating TLR4 level and MyD88-dependent pathway contributed to protection of LPS. • LPS administration also hampered DC maturation and promoted Treg differentiation.

  20. Orbital cellulits following cataract surgery under peribulbar anaesthesia

    Directory of Open Access Journals (Sweden)

    Mukherjee, Chandoshi

    2015-01-01

    Full Text Available [english] Introduction: Orbital cellulits following cataract surgery is extremely rare. We describe a case of orbital and facial cellulitis that occurred after routine cataract operation with peribulbar anaesthesia. There were no preoperative systemic or ocular risk factors for postoperative infection. Case description: An 89-year-old man presented to eye casualty, the day after he underwent an uneventful phacoemulsification and posterior chamber lens implantation in the left eye under peribulabr anaesthesia, with soreness, swelling and reduced visual acuity (6/18 in the operated eye. On initial presentation periorbital swelling was noted, the eye was minimally tender, intraocular pressure was raised at 28 mHg and fundoscopy was limited due to a hazy cornea. The patient was discharged on topical medication with a diagnosis of allergic reaction to postoperative drops.The following day, the patient re-presented with worsening orbital swelling involving the left cheek. Ocular findings remained unchanged. CT scan revealed left orbit soft tissue swelling and a locule of air medial to the medial rectus. There were no signs of sinus infection or periosteal inflammation. A diagnosis of left orbital and facial cellulitis was made and the patient was treated with intravenous antibiotics.Discussion: Our patient did not have any predisposing risk factors, therefore most likely cause of cellulitis is surgical trauma during administration of the peribulbar block. This case illustrates the need for adequate skin preparation before the administration of peribulbar anaesthesia and minimal tissue trauma during the procedure.

  1. Cataract surgery following KAMRA presbyopic implant

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    Tan TE

    2013-09-01

    Full Text Available Tien-En Tan,1,2 Jodhbir S Mehta2–4 1Yong Loo Lin School of Medicine, National University of Singapore, Singapore; 2Singapore National Eye Centre, Singapore; 3Singapore Eye Research Institute, Singapore; 4Department of Clinical Sciences, Duke-NUS Graduate Medical School, Singapore Abstract: Intrastromal corneal inlays are an emerging treatment for presbyopic patients. The KAMRA™ small aperture inlay was the first such inlay to receive Conformité Européenne (CE marking in 2005. It has been shown to improve uncorrected near and intermediate visual acuity without adversely affecting uncorrected distance visual acuity. Due to the age of presbyopic patients, they may eventually develop cataracts. In two such cases, we found that cataract surgery with the KAMRA implant left in place was not technically more difficult, and that the surgical procedure could be improved by additional ocular rotations to improve visualization. Biometry readings were reliable, and it appeared that the SRK/T formula was accurate for calculation of intraocular lens power. Cataract surgery with the KAMRA implant left in situ is a viable option for patients. Keywords: cataract surgery, KAMRA, corneal inlay, AcuTarget, presbyopia

  2. Role of sphincterotomy in extracapsular cataract surgery.

    OpenAIRE

    Cole, M D; Brown, R.; Ridgway, A. E.

    1986-01-01

    Forty patients subjected to extracapsular cataract extraction with posterior chamber intraocular lens implantation in whom a sphincterotomy was required are reported on. This method was used to counter the problems created by a small pupil during surgery. The technique is described and results evaluated.

  3. Cataract Extraction in High Myopic Eyes

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    Wan-Chen Ku

    2002-05-01

    Full Text Available Background: According to the high prevalence of myopia in Taiwan, we analyze theadopted cataract extractions, identify predicting factors for postoperativevision, and to assess the incidence of retinal complications after Nd: YAGlaser capsulotomy in high myopic eyes.Methods: One hundred and twenty-five eyes, which the axial lengths were longer than26 mm, following cataract extraction were enrolled. Surgeries adoptedincluded phacoemulsification with intraocular lens implantation, extracapsularcataract extraction with intraocular lens implantation, phacoemulsification,and extracapsular cataract extraction. Logistic regression was utilizedto assess predictive factors for postoperative vision.Results: Postoperative vision of 41 eyes (32.8% of the 125 high myopic eyesimproved at least 4 lines of Snellen acuity. Thirty-two eyes (25.6%achieved good postoperative vision (BCVA≥20/40, and 26 eyes (20.8%demonstrated poor postoperative vision (BCVA<20/200. Younger age andshorter axial length were appreciated for better visual outcome ( p < 0.05.Nd: YAG laser capsulotomy is required for posterior capsular opacity. Threein 125 eyes (2.4% developed retinal complications and 2 of them had retinaldetachment subsequently within one month after Nd: YAG laser capsulotomy.Conclusion: Most high myopic patients achieved visual improvement after cataract surgeries.Age and axial length are the predictive factors in high myopicpatients. It is crucial to examine retina prior to Nd: YAG laser capsulotomyto prevent retinal complication.

  4. Endoplasmic reticulum quality control is involved in the mechanism of endoglin-mediated hereditary haemorrhagic telangiectasia.

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    Bassam R Ali

    Full Text Available Hereditary haemorrhagic telangiectasia (HHT is an autosomal dominant genetic condition affecting the vascular system and is characterised by epistaxis, arteriovenous malformations and mucocutaneous and gastrointestinal telangiectases. This disorder affects approximately 1 in 8,000 people worldwide. Significant morbidity is associated with this condition in affected individuals, and anaemia can be a consequence of repeated haemorrhages from telangiectasia in the gut and nose. In the majority of the cases reported, the condition is caused by mutations in either ACVRL1 or endoglin genes, which encode components of the TGF-beta signalling pathway. Numerous missense mutations in endoglin have been reported as causative defects for HHT but the exact underlying cellular mechanisms caused by these mutations have not been fully established despite data supporting a role for the endoplasmic reticulum (ER quality control machinery. For this reason, we examined the subcellular trafficking of twenty-five endoglin disease-causing missense mutations. The mutant proteins were expressed in HeLa and HEK293 cell lines, and their subcellular localizations were established by confocal fluorescence microscopy alongside the analysis of their N-glycosylation profiles. ER quality control was found to be responsible in eight (L32R, V49F, C53R, V125D, A160D, P165L, I271N and A308D out of eleven mutants located on the orphan extracellular domain in addition to two (C363Y and C382W out of thirteen mutants in the Zona Pellucida (ZP domain. In addition, a single intracellular domain missense mutant was examined and found to traffic predominantly to the plasma membrane. These findings support the notion of the involvement of the ER's quality control in the mechanism of a significant number, but not all, missense endoglin mutants found in HHT type 1 patients. Other mechanisms including loss of interactions with signalling partners as well as adverse effects on functional

  5. Hippocampal molecular mechanisms involved in the enhancement of fear extinction caused by exposure to novelty.

    Science.gov (United States)

    de Carvalho Myskiw, Jociane; Furini, Cristiane Regina Guerino; Benetti, Fernando; Izquierdo, Ivan

    2014-03-25

    Exposure to a novel environment enhances the extinction of contextual fear. This has been explained by tagging of the hippocampal synapses used in extinction, followed by capture of proteins from the synapses that process novelty. The effect is blocked by the inhibition of hippocampal protein synthesis following the novelty or the extinction. Here, we show that it can also be blocked by the postextinction or postnovelty intrahippocampal infusion of the NMDA receptor antagonist 2-amino-5-phosphono pentanoic acid; the inhibitor of calcium/calmodulin-dependent protein kinase II (CaMKII), autocamtide-2-related inhibitory peptide; or the blocker of L-voltage-dependent calcium channels (L-VDCCs), nifedipine. Inhibition of proteasomal protein degradation by β-lactacystin has no effect of its own on extinction or on the influence of novelty thereon but blocks the inhibitory effects of all the other substances except that of rapamycin on extinction, suggesting that their action depends on concomitant synaptic protein turnover. Thus, the tagging-and-capture mechanism through which novelty enhances fear extinction involves more molecular processes than hitherto thought: NMDA receptors, L-VDCCs, CaMKII, and synaptic protein turnover. PMID:24591622

  6. Mechanisms and secondary factors involved in the induction of radiation transformation in vitro

    International Nuclear Information System (INIS)

    The long term of this research program was to gain information concerning the mechanisms that determine the carcinogenic effects of ionizing radiation, particularly high LET radiation exposure. The experimental approach involves parallel studies of the induction of malignant transformation in BALB/3T3 cells and of specific gene mutations in human lymphoblastoid cells. Emphasis was on the biologic effects of internally incorporated Auger electron emitting radionuclides and the initiation of studies to determine the effects of low dose-rate neutron exposure. Auger electron irradiation sever as a model for high LET-type radiation effects and as an experimental tool for studying the effects of radiation at specific sites within the cell. Auger-emitting radiosotopes are commonly used in clinical nuclear medicine, rendering them a potential hazard to human populations. We examined the influence of cellular localization of Auger-emitting radionuclides and the spectrum of energy distribution in DNA on their mutagenic, cytogenetic, and transformational effects. The effects of 125I (an energetic beta emitter) were compared. We studied the induction of cytogenetic changes by 125I exposure of the cell membrane, as well as its potential to promote (enhance) transformation initiated by low dose external x-ray exposure. We will investigate the Relative Biological Effectiveness for mutagenesis and transformation of low doses of fast neutrons delivered continuously at variable low dose-rates. 34 refs., 1 tab

  7. Mechanisms involved in alleviation of intestinal inflammation by bifidobacterium breve soluble factors.

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    Elise Heuvelin

    Full Text Available OBJECTIVES: Soluble factors released by Bifidobacterium breve C50 (Bb alleviate the secretion of pro-inflammatory cytokines by immune cells, but their effect on intestinal epithelium remains elusive. To decipher the mechanisms accounting for the cross-talk between bacteria/soluble factors and intestinal epithelium, we measured the capacity of the bacteria, its conditioned medium (Bb-CM and other Gram(+ commensal bacteria to dampen inflammatory chemokine secretion. METHODS: TNFalpha-induced chemokine (CXCL8 secretion and alteration of NF-kappaB and AP-1 signalling pathways by Bb were studied by EMSA, confocal microscopy and western blotting. Anti-inflammatory capacity was also tested in vivo in a model of TNBS-induced colitis in mice. RESULTS: Bb and Bb-CM, but not other commensal bacteria, induced a time and dose-dependent inhibition of CXCL8 secretion by epithelial cells driven by both AP-1 and NF-kappaB transcription pathways and implying decreased phosphorylation of p38-MAPK and IkappaB-alpha molecules. In TNBS-induced colitis in mice, Bb-CM decreased the colitis score and inflammatory cytokine expression, an effect reproduced by dendritic cell conditioning with Bb-CM. CONCLUSIONS: Bb and secreted soluble factors contribute positively to intestinal homeostasis by attenuating chemokine production. The results indicate that Bb down regulate inflammation at the epithelial level by inhibiting phosphorylations involved in inflammatory processes and by protective conditioning of dendritic cells.

  8. Simultaneous Penetrating Keratoplasty and Cataract Surgery

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    Mohammad-Ali Javadi

    2013-01-01

    Full Text Available Purpose: To determine the clinical outcomes of simultaneous penetrating keratoplasty (PK, cataract removal and intraocular lens implantation (triple procedure, and to compare the safety and efficacy of two different cataract extraction techniques during the course of PK. Methods: This retrospective comparative study was conducted on patients who had undergone a triple procedure. The technique of cataract extraction was either opensky extracapsular cataract extraction (ECCE or phacoemulsification (PE. In the ECCE group, the posterior chamber intraocular lens (PCIOL was implanted in the ciliary sulcus, while in the PE group PCIOLs were fixated within the capsular bag. Outcome measures included best spectacle corrected visual acuity (BSCVA, refractive results, graft clarity and complications. Results: Seventy-six eyes of 69 consecutive patients with mean age of 61.4±14.2 years were enrolled. Mean follow-up period was 61.4±37.2 months over which mean BSCVA was significantly improved from 1.40±0.68 to 0.44±0.33 LogMAR (P<0.001. Mean postoperative spherical equivalent refractive error was -2.13±3.02 D, which significantly differed from the target refraction (-0.73±0.29 D, P=0.004. At final follow-up, 89.5% of the corneal grafts remained clear. Conclusion: The triple procedure is a safe and effective approach to restore vision in patients with coexisting corneal pathologies and cataracts. However, unacceptable postoperative refractive error can be anticipated.

  9. Surgical treatment of patients with bilateral cataracts

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    I.E. Ioshin

    2013-02-01

    Full Text Available ABSTRACT The Determination of the tactics for surgical cataract treatment in the fellow eye in patients with bilateral cataracts did not received any unambiguous solution till now and the periods of operation performance are interpreted differently. The authors analyzed the results of treatment in 486 patients with bilateral cataracts. The authors identified a possible favorable interval between first and second operations in case of bilateral cataract, which was based on the clinical, functional and immunological parameters. Phacoemulsifications with peri-operative antibiotic prophylaxis were carried out not later than 4 days after the operation on the first eye, if there were no complications intra-operatively and in post-operative period in the first eye. Recommended time of surgery in the fellow eye in 114 patients of the main group allowed to reveal high functional results (0.7-1.0 in 90.4% in the first eye and in 85.1% of cases in the fellow eye, that promoted the restoration of binocular functions in 98 % of cases after surgery in the shortest possible time. In all patients of the main group the clear vision at different distances were achieved after surgery with bilateral implantation of multifocal IOLs in both eyes in the maximum shortest time. Selected dates of cataract surgery in both eyes taking into account the general and associated ocular pathology allows to reduce the emotional cost, time and organizational problems in preparation for the operation, adding the benefits of quality of early rehabilitation after surgery in both eyes.

  10. Axial length variability in cataract surgery

    International Nuclear Information System (INIS)

    To determine the mean axial length and biometric measures in patients undergoing cataract surgery and further compare the variability of axial length between the gender and with age. Study Design: Cross-sectional observational study. Place and Duration of Study: Eye Unit I, Department of Ophthalmology, Liaquat University of Medical and Health Sciences, Hyderabad, Pakistan from January 2010 to December 2012. Methodology: All patients referred for cataract surgery were assessed. The study included 886 eyes which were straightforward cataract cases with no other ocular problem. The data was collected for axial length, keratometric values and Intra-Ocular Lens (IOL) power prior to cataract surgery. The collected data was then analyzed using SPSS version 19 for windows software. Results: Gender based comparison showed significant difference in age, axial length, keratometric values and IOL power between the two groups (p=0.000). 86% of the eyes had an axial length between 21.00 mm and 23.99 mm. In univariate analysis there was significant (p=0.000) relation between overall age and axial length. The keratometric values ranged between 36.75 D and 52.50 D. Majority of the IOL powers ranged between 20.00 D and 23.00 D. Conclusion: The mean axial length of patients undergoing cataract surgery was 22.96 +- 1.04 mm, was comparable to Indian and Chinese population but shorter than the Western population. Females had shorter axial lengths, similar to other studies. Axial length was positively associated with age among the females, the cause of which is yet to be determined. (author)

  11. Mechanism involved in trichloroethylene-induced liver cancer: Importance to environmental cleanup. 1998 annual progress report

    International Nuclear Information System (INIS)

    'The objective of this project is to develop critical data for changing risk-based clean-up standards for trichloroethylene (TCE). The project is organized around two interrelated tasks: Task 1 addresses the tumorigenic and dosimetry issues for the metabolites of TCE that produce liver cancer in mice, dichloroacetate (DCA) and trichloroacetate (TCA). Early work had suggested that TCA was primarily responsible for TCE-induced liver tumors, but several, more mechanistic observations suggest that DCA may play a prominent role. This task is aimed at determining the basis for the selection hypothesis and seeks to prove that this mode of action is responsible for TCE-induced tumors. This project will supply the basic dose-response data from which low-dose extrapolations would be made. Task 2 seeks specific evidence that TCA and DCA are capable of promoting the growth of spontaneously initiated cells from mouse liver, in vitro. The data provide the clearest evidence that both metabolites act by a mechanism of selection rather than mutation. These data are necessary to select between a linear (i.e. no threshold) and non-linear low-dose extrapolation model. As of May of 1998, this research has identified two plausible modes of action by which TCE produces liver tumors in mice. These modes of action do not require the compounds to be mutagenic. The bulk of the experimental evidence suggests that neither TCE nor the two hepatocarcinogenic metabolites of TCE are mutagenic. The results from the colony formation assay clearly establish that both of these metabolites cause colony growth from initiated cells that occur spontaneously in the liver of B 6 C 3 F 1 mice, although the phenotypes of the colonies differ in the same manner as tumors differ, in vivo. In the case of DCA, a second mechanism may occur at a lower dose involving the release of insulin. This observation is timely as it was recently reported that occupational exposures to trichloroethylene results in 2 to 4-fold

  12. Inhibitory Effect of Crocin(s) on Lens α-Crystallin Glycation and Aggregation, Results in the Decrease of the Risk of Diabetic Cataract

    OpenAIRE

    Fereshteh Bahmani; Seyedeh Zahra Bathaie; Seyed Javid Aldavood; Arezou Ghahghaei

    2016-01-01

    The current study investigates the inhibitory effect of crocin(s), also known as saffron apocarotenoids, on protein glycation and aggregation in diabetic rats, and α-crystallin glycation. Thus, crocin(s) were administered by intraperitoneal injection to normal and streptozotocin-induced diabetic rats. The cataract progression was recorded regularly every two weeks and was classified into four stages. After eight weeks, the animals were sacrificed and the parameters involved in the cataract fo...

  13. VISUAL OUTCOME OF PHACOEMULSIFICATION WITH THE HYDROPHILIC IOL IMPLANTATION IN COMPLICATED CATARACT SECONDARY TO UVEITIS

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    Jayshri V

    2015-11-01

    Full Text Available AIM: To study the Visual outcome of Phacoemulsification with the hydrophilic IOL implantation in complicated cataract secondary to uveitis. METHOD: This was a prospective study on 40 eyes of 40 patients with uveitic cataract, who underwent Phacoemulsification with hydrophilic IOL at a tertiary care centre in central India over a period of 2 years. In our study after preoperative control of inflammation for minimum 3 months Phacoemulsification was performed and results were observed with the aim to study visual outcome of Phacoemulsification with hydrophilic IOL in complicated cataract secondary to uveitis. RESULTS: Mean age of the subjects in the study was 40.5 yrs. Etiologically, idiopathic uveitis was most common cause (24 cases, followed by tuberculosis (8 cases. One year post-operatively, 92.5% of subjects had ≥2 snellen’s lines improvement and of these 80% (30 of subjects had visual acuity of ≥6/18. The main complications affecting visual outcomes were Macular involvement and optic neuropathy. PCO was the commonest complication observed in 12 subjects. CONCLUSION: Phacoemulsification with implantation of a hydrophillic PC IOL in the capsular bag is safe and effective in patients with coexisting uveitis and cataract, provided that the ocular inflammation is under control.

  14. Method and apparatus for removing cataractous lens tissue by laser radiation

    International Nuclear Information System (INIS)

    The invention under discussion contemplates apparatus and technique for surgically non-invasive surgery to remove cateracted-lens tissue, enabling the beam output of a laser to be focused from a convergentray bundle to a focal spot of maximum power density at the anterior surface of a cataracted lens and which scans the focal spot over a predetermined area or areas of the cataracted lens. The beam is a focal and therefore diffuse as it enters the eye through the cornea, and it is also diffuse (being divergent) in the controllably unlikely event that the laser energy pases through an opening it has created in the cataracted lens; the diffusion assures against damage to either or both of the cornea and the retina, for power levels sufficient to achieve ablative photodecomposition and/or thermal decomposition and/or photofragmentation and/or photoemulsification of the cataracted-lens tissue. Various features are disclosed for assuring safety and uniformity in the removal of involved tissue

  15. Theater for Development Methodology in Childhood Cataract Case Finding

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    Roseline Ekanem Duke

    2016-03-01

    Full Text Available The key informant methodology for case finding for childhood cataract  was utilized  in a rural population in Nigeria to identify suitable children who would benefit surgically from intervene for cataract and restore vision such children. It was however noticed that some parents who had children with cataract did not bring their children to the primary health center for examination and recommendation. The purpose of this study is to investigate the benefits of using the theatre for development approach in childhood cataract case finding. The delay in identification and referral of children with cataract at an appropriate age for surgical intervention and optical rehabilitation is the main cause of poor vision following surgery for the condition as amblyopia results. Therefore early presentation, identification, referral and surgical intervention as well as appropriate optical rehabilitation is the key to successful surgical outcome of childhood cataract and good visual prognosis. The theater for development (TfD approach methodology was implemented in a community in Akpabuyo local government are of Cross River state, Nigeria as a means to enhance community participation, health promotion and education and to complement the key informant methodology in case finding for childhood cataract. Three children with cataracts were referred by the community following the TfD intervention, for cataract surgery and uptake of follow up care after surgery. The TfD approach appears to be a useful method for encouraging community participation in the case finding of childhood cataract.

  16. Self-assembly of protein aggregates in ageing disorders: the lens and cataract model.

    Science.gov (United States)

    Clark, John I

    2013-05-01

    Cataract, neurodegenerative disease, macular degeneration and pathologies of ageing are often characterized by the slow progressive destabilization of proteins and their self-assembly to amyloid-like fibrils and aggregates. During normal cell differentiation, protein self-assembly is well established as a dynamic mechanism for cytoskeletal organization. With the increased emphasis on ageing disorders, there is renewed interest in small-molecule regulators of protein self-assembly. Synthetic peptides, mini-chaperones, aptamers, ATP and pantethine reportedly regulate self-assembly mechanisms involving small stress proteins, represented by human αB-crystallin, and their targets. Small molecules are being considered for direct application as molecular therapeutics to protect against amyloid and protein aggregation disorders in ageing cells and tissues in vivo. The identification of specific interactive peptide sites for effective regulation of protein self-assembly is underway using conventional and innovative technologies. The quantification of the functional interactions between small stress proteins and their targets in vivo remains a top research priority. The quantitative parameters controlling protein-protein interactions in vivo need characterization to understand the fundamental biology of self-assembling systems in normal cells and disorders of ageing. PMID:23530262

  17. Orally active multi-functional antioxidants delay cataract formation in streptozotocin (type 1 diabetic and gamma-irradiated rats.

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    James Randazzo

    -functional antioxidants delayed cataract formation in two diverse rat models. These studies provide a proof of concept that a general cataract treatment focused on reducing oxidative stress instead of a specific mechanism of cataractogenesis can be developed.

  18. Physiological mechanisms involved in resistance to cotton verticillium wilt induced by AM fungi

    Institute of Scientific and Technical Information of China (English)

    LIU Bing-jiang; LIU Run-jin

    2004-01-01

    @@ It was proved that arbuscular mycorrhizal (AM) fungi played an important role in increasing plant resistance to soilborne pathogens, especially when plants were pre-inoculated with AM fungi.Mechanisms involved in this phenomenon are not yet well understood. On the basis of the former experiment results in our lab, effects of AM fungi on cotton Verticillium wilt and the mechanisms of increasing disease resisitance by the tested fungi were studied in pot culture under greenhouse conditions. Two cotton cutivars Litai 8 and 86-1 which are susceptible to Verticillium dahliae were pre-inoculated with Glomus fasiculatum, and Gigaspora margarita, then inoculated with the strain of Verticillium dahliae, namely "An-Yang" (belong to intermediate virulent type) 30 days after the former inoculation. Results showed that AM fungi could improve the growth and development of cotton plants, increase plants dry mass, decrease incidence and disease index of Verticillium wilt of cotton plants, inhibit the infection and development of V. dahliae to different extent in the rhizosphere of cotton pre-inoculated with AM fungi, while the colonization and spore numbers of AM fungi were not reduced significantly by this pathogen. The defence enzymes, such as phenylalanine ammonia-lyase (PAL), chitinase, β-1, 3-glucanase, peroxidase, polyphenoloxidase (PPO) were induced, and their activities and peak increased by AM fungi in roots and leaves, and the increasing speed and peak of the enzyme activity were higher in treatment with AM fungus preinoculation than the inoculation with only V. dahliae, which suggested that defense response was activated by AM fungi, and then made the cotton to react strongly and rapidly to the infection of V. dahliae. In addition, AM fungi decreased the content of malondiadehyde (MDA) in cotton roots and leaves,protected membrane system and alleviated the damage caused by the pathogen. The AM fungus,Glomus fasiculatum showed the superior effects of biological

  19. Mechanisms of Action Involved in Ozone Therapy: Is healing induced via a mild oxidative stress?

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    Sagai Masaru

    2011-12-01

    moderate oxidative stress. Recently these concepts have become widely accepted. The versatility of ozone in treating vascular and degenerative diseases as well as skin lesions, hernial disc and primary root carious lesions in children is emphasized. Further researches able to elucidate whether the mechanisms of action of ozone therapy involve nuclear transcription factors, such as Nrf2, NFAT, AP-1, and HIF-1α are warranted.

  20. Mechanisms of Action Involved in Ozone Therapy: Is healing induced via a mild oxidative stress?

    Science.gov (United States)

    2011-01-01

    oxidative stress. Recently these concepts have become widely accepted. The versatility of ozone in treating vascular and degenerative diseases as well as skin lesions, hernial disc and primary root carious lesions in children is emphasized. Further researches able to elucidate whether the mechanisms of action of ozone therapy involve nuclear transcription factors, such as Nrf2, NFAT, AP-1, and HIF-1α are warranted. PMID:22185664

  1. Pathophysiological mechanisms involved in non-alcoholicsteatohepatitis and novel potential therapeutic targets

    Institute of Scientific and Technical Information of China (English)

    2015-01-01

    Non-alcoholic fatty liver disease (NAFLD) is a major healthcare problem and represents the hepatic expression ofthe metabolic syndrome. NAFLD is classified as nonalcoholicfatty liver (NAFL) or simple steatosis, and nonalcoholicsteatohepatitis (NASH). NASH is characterizedby the presence of steatosis and inflammation withor without fibrosis. The physiopathology of NAFL andNASH and their progression to cirrhosis involve severalparallel and interrelated mechanisms, such as, insulinresistance (IR), lipotoxicity, inflammation, oxidativestress, and recently the gut-liver axis interaction has beendescribed. Incretin-based therapies could play a role inthe treatment of NAFLD. Glucagon-like peptide-1 (GLP-1)is an intestinal mucosa-derived hormone which is secretedinto the bloodstream in response to nutrient ingestion;it favors glucose-stimulated insulin secretion, inhibitionof postprandial glucagon secretion and delayed gastricemptying. It also promotes weight loss and is involvedin lipid metabolism. Once secreted, GLP-1 is quicklydegraded by dipeptidyl peptidase-4 (DPP-4). Therefore,DPP-4 inhibitors are able to extend the activity of GLP-1.Currently, GLP-1 agonists and DPP-4 inhibitors representattractive options for the treatment of NAFLD andNASH. The modulation of lipid and glucose metabolismthrough nuclear receptors, such as the farsenoid Xreceptor, also constitutes an attractive therapeutic target.Obeticholic acid is a potent activator of the farnesoidX nuclear receptor and reduces liver fat content andfibrosis in animal models. Ursodeoxycholic acid (UDCA)is a hydrophilic bile acid with immunomodulatory, antiinflammatory,antiapoptotic, antioxidant and antifibroticproperties. UDCA can improve IR and modulatelipid metabolism through its interaction with nuclearreceptors such as, TGR5, farnesoid X receptor-a, orthe small heterodimeric partner. Finally, pharmacologicmodulation of the gut microbiota could have a role in thetherapy of NAFLD and

  2. Study of the mechanisms involved in the laser superficial hardening process of metallic alloys

    International Nuclear Information System (INIS)

    The laser superficial hardening process of a ferrous alloy (gray cast iron) and of an aluminum-silicon alloy was investigated in this work. These metallic alloys are used in the automobile industry for manufacturing cylinders and pistons, respectively. By application of individual pulses and single tracks, the involved mechanisms during the processing were studied. Variables such as energy density, power density, temporal width, beam diameter on the sample surface, atmosphere of the processing region, overlapping and scanning velocity. The hardened surface was characterized by optical and scanning electronic microscopy, dispersive energy microanalysis, X-ray mapping, X-ray diffraction, and measurements of roughness and Vickers microhardness. Depending on the processing parameters, it is possible to obtain different microstructures. The affected area of gray cast iron, can be hardened by remelting or transformation hardening (total or partial) if the reached temperature is higher or not that of melting temperature. Laser treatment originated new structures such as retained austenite, martensite and, occasionally, eutectic of cellular dendritic structure. Aluminum-silicon alloy does not have phase transformation in solid state, it can be hardened only by remelting. The increase of hardness is a function of the precipitation hardening process, which makes the silicon particles smaller and more disperse in the matrix. Maximal values of microhardness (700-1000 HV) were reached with the laser treatment in gray cast iron samples. The initial microhardness is of 242 HV. For aluminum-silicon alloy, the laser remelting increases the initial microhardness of 128 HV to the range of 160-320 HV. The found results give a new perspective for using the CLA/IPEN's laser in the heat treatment area. Besides providing a higher absorptivity to the materials, compared with the CO2 laser, and optical fiber access, the superficial hardening with Nd:YAG laser, depending on the level of

  3. Mechanisms involved in the selective transfer of long chain polyunsaturted fatty acids to the fetus

    Directory of Open Access Journals (Sweden)

    Alfonso eGil-Sánchez

    2011-09-01

    Full Text Available The concentration of long chain polyunsaturated fatty acid (LCPUFA in the fetal brain increases dramatically from the third trimester until 18 months of life. Several studies have shown an association between the percentage of maternal plasma docosahexaenoic acid (DHA during gestation and development of the cognitive functions in the neonate. Since only very low levels of LCPUFA are synthesized in the fetus and placenta, their primary source for the fetus is that of maternal origin. Both in vitro and human in vivo studies using labelled fatty acids have shown the preferential transfer of LCPUFA from the placenta to the fetus compared with other fatty acids, although the mechanisms involved are still uncertain. The placenta takes up circulating maternal non-esterified fatty acids (NEFA and fatty acids released mainly by maternal lipoprotein lipase and endothelial lipase. These NEFA may enter the cell by passive diffusion or by means of membrane carrier proteins. Once in the cytosol, NEFA bind to cytosolic fatty acid-binding proteins for transfer to the fetal circulation or can be oxidized within the trophoblasts and even re-esterified and stored in lipid droplets (LD. Although trophoblast cells are not specialized in lipid storage, LCPUFA may up-regulate peroxisome proliferator activated receptor-γ (PPARγ and hence the gene expression of fatty acid transport carriers, fatty acid acyl-CoA synthetases and adipophilin or other enzymes related with lipolysis, modifying their rate of placental transfer and metabolization. The placental transfer of LCPUFA during pregnancy seems to be a key factor in the neurological development of the fetus. Increased knowledge on the factors that modify placental transfer of fatty acids would contribute to our understanding of this complex process.

  4. Cataracts and Other Common Eye Diseases | NIH MedlinePlus the Magazine

    Science.gov (United States)

    ... on. Feature: Treating Cataracts Cataracts and Other Common Eye Diseases Past Issues / Summer 2014 Table of Contents Click ... are more likely to develop a cataract. Diabetic Eye Disease Diabetic Retinopathy : A scene as it might be ...

  5. Measurements of attenuation coefficient for evaluating the hardness of a cataract lens by a high-frequency ultrasonic needle transducer

    Science.gov (United States)

    Huang, Chih-Chung; Chen, Ruimin; Tsui, Po-Hsiang; Zhou, Qifa; Humayun, Mark S.; Shung, K. Kirk

    2009-10-01

    A cataract is a clouding of the lens in the eye that affects vision. Phacoemulsification is the mostly common surgical method for treating cataracts, and determining that the optimal phacoemulsification energy is dependent on measuring the hardness of the lens. This study explored the use of an ultrasound needle transducer for invasive measurements of ultrasound attenuation coefficient to evaluate the hardness of the cataract lens. A 47 MHz high-frequency needle transducer with a diameter of 0.9 mm was fabricated by a polarized PMN-33%PT single crystal in the present study. The attenuation coefficients at different stages of an artificial porcine cataract lens were measured using the spectral shift approach. The hardness of the cataract lens was also evaluated by mechanical measurement of its elastic properties. The results demonstrated that the ultrasonic attenuation coefficient was increased from 0.048 ± 0.02 to 0.520 ± 0.06 dB mm-1 MHz-1 corresponding to an increase in Young's modulus from 6 ± 0.4 to 96 ± 6.2 kPa as the cataract further developed. In order to evaluate the feasibility of combining needle transducer and phacoemulsification probe for real-time measurement during cataract surgery, the needle transducer was mounted on the phacoemulsification probe for a vibration test. The results indicated that there was no apparent damage to the tip of the needle transducer and the pulse-echo test showed that a good performance in sensitivity was maintained after the vibration test.

  6. Measurements of attenuation coefficient for evaluating the hardness of a cataract lens by a high-frequency ultrasonic needle transducer

    Energy Technology Data Exchange (ETDEWEB)

    Huang, C.-C. [Department of Electronic Engineering, Fu Jen Catholic University, Taipei 24205, Taiwan (China); Chen Ruimin; Zhou Qifa; Shung, K Kirk [NIH Resource on Medical Ultrasonic Transducer Technology, Department of Biomedical Engineering, University of Southern California, Los Angeles, CA 90089 (United States); Tsui, P.-H. [Division of Mechanics, Research Center for Applied Sciences, Academia Sinica, Taipei 11529, Taiwan (China); Humayun, Mark S [Doheny Retina Institute, Doheny Eye Institute, Department of Ophthalmology, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033 (United States)], E-mail: j648816n@ms23.hinet.net

    2009-10-07

    A cataract is a clouding of the lens in the eye that affects vision. Phacoemulsification is the mostly common surgical method for treating cataracts, and determining that the optimal phacoemulsification energy is dependent on measuring the hardness of the lens. This study explored the use of an ultrasound needle transducer for invasive measurements of ultrasound attenuation coefficient to evaluate the hardness of the cataract lens. A 47 MHz high-frequency needle transducer with a diameter of 0.9 mm was fabricated by a polarized PMN-33%PT single crystal in the present study. The attenuation coefficients at different stages of an artificial porcine cataract lens were measured using the spectral shift approach. The hardness of the cataract lens was also evaluated by mechanical measurement of its elastic properties. The results demonstrated that the ultrasonic attenuation coefficient was increased from 0.048 {+-} 0.02 to 0.520 {+-} 0.06 dB mm{sup -1} MHz{sup -1} corresponding to an increase in Young's modulus from 6 {+-} 0.4 to 96 {+-} 6.2 kPa as the cataract further developed. In order to evaluate the feasibility of combining needle transducer and phacoemulsification probe for real-time measurement during cataract surgery, the needle transducer was mounted on the phacoemulsification probe for a vibration test. The results indicated that there was no apparent damage to the tip of the needle transducer and the pulse-echo test showed that a good performance in sensitivity was maintained after the vibration test.

  7. Measurements of attenuation coefficient for evaluating the hardness of a cataract lens by a high-frequency ultrasonic needle transducer

    International Nuclear Information System (INIS)

    A cataract is a clouding of the lens in the eye that affects vision. Phacoemulsification is the mostly common surgical method for treating cataracts, and determining that the optimal phacoemulsification energy is dependent on measuring the hardness of the lens. This study explored the use of an ultrasound needle transducer for invasive measurements of ultrasound attenuation coefficient to evaluate the hardness of the cataract lens. A 47 MHz high-frequency needle transducer with a diameter of 0.9 mm was fabricated by a polarized PMN-33%PT single crystal in the present study. The attenuation coefficients at different stages of an artificial porcine cataract lens were measured using the spectral shift approach. The hardness of the cataract lens was also evaluated by mechanical measurement of its elastic properties. The results demonstrated that the ultrasonic attenuation coefficient was increased from 0.048 ± 0.02 to 0.520 ± 0.06 dB mm-1 MHz-1 corresponding to an increase in Young's modulus from 6 ± 0.4 to 96 ± 6.2 kPa as the cataract further developed. In order to evaluate the feasibility of combining needle transducer and phacoemulsification probe for real-time measurement during cataract surgery, the needle transducer was mounted on the phacoemulsification probe for a vibration test. The results indicated that there was no apparent damage to the tip of the needle transducer and the pulse-echo test showed that a good performance in sensitivity was maintained after the vibration test.

  8. Magnetic resonance imaging study on rat sugar cataract

    International Nuclear Information System (INIS)

    Proton nuclear magnetic resonance (1H-NMR) is one of the most important methods for noninvasively evaluating the state of water in the biological system. It could be useful for evaluation of the early changes of cataract. In this study, in vivo magnetic resonance imaging (MRI) was applied to rat galactosemic cataract, which is a model of the human diabetic cataract, and compared with the histological findings. The relationship between the relaxation times (T1, T2) and the water contents were discussed. The T1 and T2 values were prolonged and the high intensity area of the lens cortex was enlarged from the early stage of the cataract (two days after the intake of galactose). These changes preceded the histological changes. This suggests that MRI is applicable for the evaluation of anti-cataract agents, for example aldose reductase inhibitors, against human diabetic cataract. (author)

  9. Risk of Retinal Detachment After Pediatric Cataract Surgery

    DEFF Research Database (Denmark)

    Haargaard, Birgitte; Andersen, Elisabeth W; Oudin, Anna; Poulsen, Gry; Wohlfahrt, Jan; la Cour, Morten; Melbye, Mads

    2014-01-01

    PURPOSE: To determine the long-term risk of retinal detachment following pediatric cataract surgery and to identify risk factors for retinal detachment. METHODS: We included all children (aged 0 to 17 years) who during the time period of 1977 to 2005 underwent pediatric cataract surgery in Denmark...... was based on medical chart review. RESULTS: Among 1043 eyes of 656 children undergoing surgery for pediatric cataract, 25 eyes (23 children) developed retinal detachment at a median time of 9.1 years after surgery. The overall 20-year risk of retinal detachment was 7% (95% confidence interval [CI]: 3...... (16% [95% CI: 6%-24%]). CONCLUSIONS: The estimated overall risk of retinal detachment 20 years after pediatric cataract surgery was 7%, but only 3% for isolated cataract. Particularly high risks of retinal detachment after cataract surgery were associated with mental retardation and having other...

  10. Laser-assisted cataract surgery and other emerging technologies for cataract removal

    Directory of Open Access Journals (Sweden)

    Aasuri Murali

    1999-01-01

    Full Text Available As we near the end of this century, refractive cataract surgery has become a reality through concerted contributions from ultrasonic phacoemulsification, foldable intraocular lens (IOL implantation technology and keratorefractive surgery. As we enter the new millennium, our sights are set on realizing another dream: accommodative IOL surgery. Towards achieving this goal, many advances have been made in both techniques and technology of cataract removal. Lasers in particular have been under investigation for cataract removal for nearly two decades. The technology has now reached a stage where cataract can indeed be removed entirely with laser alone. Neodymium:YAG and erbium:YAG are the laser sources currently utilized by manufacturers of laser phaco systems. Initial clinical experience reported in the literature has served to highlight the capabilities of lasers and the need for further refinement. Despite the excitement associated with the availability of this alluring new technology for cataract removal, it is necessary to develop more effective laser systems and innovative surgical techniques that optimize its capabilities if laser phaco surgery is to be a genuine improvement over current techniques.

  11. Sutureless Non-phaco Cataract Surgery: A Solution to Reduce Worldwide Cataract Blindness?

    Directory of Open Access Journals (Sweden)

    Albrecht Hennig

    2003-01-01

    Full Text Available The Search for Appropriate Sutureless Cataract Surgery. During the last decade, in industrialised countries phacoemulsification has largely replaced ab-externo extracapsular cataract extraction with posterior chamber intraocular lenses (ECCE/PC IOL with sutures. The small self-sealing phaco incision provides rapid visual rehabilitation, and the surgery is increasingly done on an outpatient basis. However, in developing countries phacoemulsification is performed only on selected patients, usually those able to pay high treatment charges. The reasons for this include the cost of a phaco machine and consumables such as foldable IOLs. Until now, phacoemulsification has played a very limited role in the reduction of cataract blindness in low income countries. Therefore, eye surgeons in developing countries are searching for alternatives to phacoemulsification. We need a surgical technique which is easy to learn, provides an immediate good uncorrected visual outcome, and is affordable to most cataract patients. Such a technique would advance cataract surgery in low income countries and contribute to reaching the goal of VISION 2020: The Right to Sight.

  12. Manual cataract extraction via a subconjunctival limbus oblique incision for mature cataracts

    Directory of Open Access Journals (Sweden)

    J Yang

    2014-01-01

    Full Text Available Aims: To report the technique and outcomes of sutureless manual cataract extraction via a subconjunctival limbus oblique incision for mature cataracts. Materials and Methods: This retrospective study comprised of 112 eyes of 83 patients with mature cataract who all had manual cataract extraction via a subconjunctival limbus oblique incision. A transconjunctival tunnel is fashioned with a 3.0 mm keratome, 0.5 mm behind the limbal vascular arcades. A limbal tunnel, with a transverse extent of 9 mm in the cornea and 7.0 mm in the limbus, is created beneath the conjunctival/Tenon′s tissue using an angled bevel-up crescent blade. Outcome measures included visual acuity, intraoperative complications, surgically induced astigmatism, endothelial cell loss rate and surgery time. Results: Self-sealing wound was achieved in 112 eyes (98.2%. The nucleus was delivered in whole in 108 eyes (96.4%. Intraoperative complications included hyphema in 3 eyes (2.7%, iridodialysis in 2 eyes 1.8%, posterior capsular rupture and zonular dialysis in 2 eyes (1.8%. At the 3-month follow-up, 91% patients achieved a best-corrected visual acuity of 20/20 or better, the mean of surgically induced astigmatism was -0.62 ± 0.41 Diopters and endothelial cell loss was 4.2%. Average surgical time was 3.75 min per case. Conclusion: This subconjunctival limbus oblique incision has the potential to serve as safe and effective technique for mature cataracts.

  13. Safety and efficacy of the transition from extracapsular cataract extraction to manual small incision cataract surgery in prevention of blindness campaigns

    OpenAIRE

    Isabel Signes-Soler; Jaime Javaloy; Gonzalo Munoz; Tomas Moya; Raul Montalban; Cesar Albarran

    2016-01-01

    Purpose: To compare the safety and the visual outcomes of two experienced cataract surgeons who converted from extracapsular cataract extraction (ECCE) to manual small incision cataract surgery (MSICS) during a campaign for the prevention of blindness. Methods: Two surgeons used the ECCE technique (ECCE group) during a campaign in Burkina Faso on 93 consecutive cataract patients with a corrected distance visual acuity (CDVA)

  14. The effects of blunt trauma and cataract surgery on corneal endothelial cell density

    OpenAIRE

    Yeniad Baris; Corum Isik; Ozgun Cahit

    2010-01-01

    Purpose: This study was designed to investigate the effects of trauma and cataract surgery on corneal endothelial cell density (ECD) in patients with a traumatic cataract due to blunt trauma without globe laceration. Materials and Methods: In this prospective study, 31 subjects with traumatic cataract (traumatic cataract group) and 30 subjects with a senile cataract (control group) were enrolled. The subjects with traumatic cataract were subdivided into two groups: uncomplicated surgery subg...

  15. Cataract Surgery and Falls, Fractures, and Mortality in the United States Population

    OpenAIRE

    Tseng, Victoria Li-Ting

    2016-01-01

    Cataract surgery is the mainstay of treatment for visually significant cataract. Aside from vision improvement, one secondary benefit of cataract surgery that has been reported is the reduction of fracture risk. This dissertation examines associations between cataract surgery and factors related to fracture risk, including the association between cataract surgery and falls and the association between cataract surgery and long-term mortality. The first study of this dissertation uses data from...

  16. Microscopic MR imaging of cataracts at 200 MHz

    International Nuclear Information System (INIS)

    An MR microscope (gradient strength, up to 100 gauss/cm; diameter, 7 mm; typical resolution, 20-40 μm) operating at 200 MHz is used to study cataract formation in a rat cataract model. Factors determining image intensity at 200 MHz such as T1, T2, and diffusion are discussed. In particular, these gradient strengths are typical for pulsed gradient diffusion experiments. The authors compare image intensity with the cellular changes accompanying cataract formation

  17. Sutureless Cataract Extraction: Complications and Management; Learning Curves

    Directory of Open Access Journals (Sweden)

    Bernd Schroeder

    2003-01-01

    Full Text Available A key issue in converting to sutureless cataract surgery is training. This article first describes the main surgical steps and complications of sutureless cataract extraction and their management. The second part reports on the training of 11 surgeons in sutureless cataract extraction at Sagarmatha Choudhary Eye Hospital, Lahan. The stepwise, supervised training is described and the learning curves of 11 surgeons analysed.

  18. Surgical magnification for intracapsular cataract surgery in a rural hospital

    OpenAIRE

    Braganza Andrew; Cheng Arthur; Thomas Ravi; Muliyil Jayaprakash

    1996-01-01

    Intracapsular cataract extraction is still the most common type of operation performed in India, especially in eye camps, and most of these are done without magnification. To assess the surgical outcome of intracapsular cataract surgery in a rural hospital with various magnifying systems, 121 consecutive eyes (121 patients) with uncomplicated cataract were randomly allocated to surgery with the operating microscope, binocular loupe or unaided eye. The surgery was performed by either consultan...

  19. Theater for Development Methodology in Childhood Cataract Case Finding

    OpenAIRE

    Roseline Ekanem Duke

    2016-01-01

    The key informant methodology for case finding for childhood cataract  was utilized  in a rural population in Nigeria to identify suitable children who would benefit surgically from intervene for cataract and restore vision such children. It was however noticed that some parents who had children with cataract did not bring their children to the primary health center for examination and recommendation. The purpose of this study is to investigate the benefits of using the theatre for developmen...

  20. The First Cataract Surgeons in Anglo-America

    OpenAIRE

    Leffler, Christopher T; Schwartz, Stephen G.; Grzybowski, Andrzej; Puneet S. Braich

    2014-01-01

    We tried to identify the earliest cataract surgeons in the English-speaking areas of America. In 1751, couching was performed on the Caribbean island of Montserrat by John Morphy. William Stork of England, who couched cataracts, practiced in Jamaica in 1760 and then in cities from Annapolis to Boston between 1761 and 1764. Frederick William Jericho of Germany, upon completion of his training at Utrecht, published his 1767 treatise on his preferred surgical technique of extracapsular cataract ...

  1. Extracapsular cataract extraction under local anaesthesia without retrobulbar injection.

    OpenAIRE

    Redmond, R M; Dallas, N L

    1990-01-01

    Day-case cataract surgery and the need for local anaesthesia are likely to increase. Retrobulbar (and peribulbar) anaesthetic injection is a common technique in cataract surgery, but serious complications are persistently reported. Subconjunctival injection is an alternative that avoids these risks. This retrospective study compares two groups of patients that underwent extracapsular cataract surgery under local anaesthetic. One group (retrobulbar) had uncomplicated retrobulbar injection with...

  2. The pattern of cataract surgery in India: 1992

    OpenAIRE

    Gupta A; Ellwein Leon

    1995-01-01

    Surgery for cataract blindness, a major health problem, is undergoing a rapid transition. This study characterizes cataract surgery in India in terms of practice setting and surgical procedure. A survey questionnaire was mailed in December 1992 to 4356 members of the All India Ophthalmological Society, resident in India, requesting data on cataract surgery cases within the past 12 months. Two thousand one hundred thirty-four (49%) ophthalmologists responded to the survey. Of the 1,023,...

  3. Cytological factors relating to posterior capsule opacification following cataract surgery.

    OpenAIRE

    Jacob, T J; Humphry, R. C.; Davies, E. G.; Thompson, G M

    1987-01-01

    Simulated extracapsular cataract extractions on cadaver eyes were performed which demonstrated that the cells of the anterior capsule remain largely intact and that only a small amount of cortical lens matter remains postoperatively. Human lens epithelial cells from normal and cataractous lenses were grown in culture. There was no appreciable difference in growth rate between cells from normal and those from cataractous lenses or between equatorial and central capsule cells. The cells grew fr...

  4. Some blood plasma constituents correlate with human cataract.

    OpenAIRE

    Donnelly, C.A; Seth, J; Clayton, R M; Phillips, C I; Cuthbert, J; Prescott, R J

    1995-01-01

    AIMS--To look for differences between matched pairs of patients and controls in concentrations of various plasma constituents which might indicate dysfunctions associated with cataract. METHOD--One thousand patients were taken from the cataract waiting list of a specialist eye hospital. For each patient a matched control of the same sex and half-decade of age but without cataract was taken from the patient list of the family doctor of the patient; the control was the next alphabetically after...

  5. Mechanisms involved in the psychological distress of Black Caribbeans in the United States

    Science.gov (United States)

    Govia, Ishtar O.

    The mental health of ethnic minorities in the United States is of urgent concern. The accelerated growth of groups of ethnic minorities and immigrants in the United States and the stressors to which they are exposed, implores academic researchers to investigate more deeply health disparities and the factors that exacerbate or minimize such inequalities. This dissertation attended to that concern. It used data from the National Survey of American Life (NSAL), the first survey with a national representative sample of Black Caribbeans, to explore mechanisms that involved in the psychological distress of Black Caribbeans in the United States. In a series of three studies, the dissertation investigated the role and consequence of (1) chronic discrimination, immigration factors, and closeness to ethnic and racial groups; (2) personal control and social support; and (3) family relations and social roles in the psychological distress of Black Caribbeans. Study 1 examined how the associations between discrimination and psychological distress were buffered or exacerbated by closeness to ethnic group and closeness to racial group. It also examined how these associations differed depending on immigration factors. Results indicated that the buffering or exacerbating effect of ethnic and racial group closeness varied according to the type of discrimination (subtle or severe) and were more pronounced among those born in the United States. Using the stress process framework, Study 2 tested moderation and mediation models of the effects of social support and personal control in the association between discrimination and distress. Results from a series of analyses on 579 respondents suggested that personal control served as a mediator in this relationship and that emotional support exerted a direct distress deterring function. Study 3 investigated sex differences in the associations between social roles, intergenerational family relationship perceptions and distress. Results

  6. Mangiferin, a natural xanthone, accelerates gastrointestinal transit in mice involving cholinergic mechanism

    Institute of Scientific and Technical Information of China (English)

    Talita Cavalcante Morais; Synara Cavalcante Lopes; Karine Maria Martins Bezerra Carvalho; Bruno Rodrigues Arruda; Francisco Thiago Correia de Souza; Maria Teresa Salles Trevisan; Vietla Satyanarayana Rao; Flávia Almeida Santos

    2012-01-01

    AIM:To investigate the effects of mangiferin on gastrointestinal transit (GIT) in normal and constipated mice,together with the possible mechanism.METHODS:Intragastrically-administered charcoal meal was used to measure GIT in overnight starved Swiss mice.In the first experiments,mangiferin (3 mg/kg,10mg/kg,30 mg/kg,and 100 mg/kg,po) or tegaserod (1mg/kg,ip) were administered 30 min before the charcoal meal to study their effects on normal transit.In the second series,mangiferin (30 mg/kg) was tested on delayed GIT induced by several different pharmacological agonists (morphine,clonidine,capsaicin) or antagonists (ondansetron,verapamil,and atropine) whereas in the third series,mangiferin (30 mg/kg,100mg/kg and 300 mg/kg) or tegaserod (1 mg/kg) were tested on 6 h fecal pellets outputted by freely fed mice.The ratio of wet to dry weight was calculated and used as a marker of fecal water content.RESULTS:Mangiferin administered orally significantly (P < 0.05) accelerated GIT at 30 mg/kg and 100 mg/kg (89%and 93%,respectively),similarly to 5-hydroxytryptamine4 (5-HT4) agonist tegaserod (81%) when compared to vehicle-treated control (63%).Co-administered mangiferin (30 mg/kg) totally reversed the inhibitory effect of opioid agonist morphine,5-HT3-receptor antagonist ondansetron and transient receptor potential vanilloid-1 receptor agonist capsaicin on GIT,but only to a partial extent with the GIT-delay induced by α2-adrenoceptor agonist clonidine,and calcium antagonist verapamil.However,co-administered atropine completely blocked the stimulant effect of mangiferin on GIT,suggesting the involvement of muscarinic acetylcholine receptor activation.Although mangiferin significantly enhanced the 6 h fecal output at higher doses (245.5 ± 10.43 mg vs 161.9 ± 10.82 mg and 227.1 ± 20.11 mg vs 161.9 ±10.82 mg of vehicle-treated control,at 30 and 100 mg/kg,P < 0.05,respectively),the effect of tegaserod was more potent (297.4 ± 7.42 mg vs 161.9 ± 10.82 mg of

  7. New cystotome for intercapsular cataract procedures.

    Science.gov (United States)

    Joyce, P W; Allarakhia, L

    1990-05-01

    Intercapsular cataract extraction, a variation of extracapsular cataract extraction (ECCE), has recently become popular, particularly in Europe and Asia. It is gaining popularity in the United States among both phacoemulsification and planned ECCE surgeons. The initial steps in the intercapsular capsulotomy include either a linear or curvilinear opening. To facilitate anterior capsulotomy for intercapsular surgery, we developed a disposable 27-gauge cystotome with a specially designed curved configuration. This cystotome also facilitates capsulotomies in deep-set eyes, which may be difficult when standard cystotomes are used. The new cystotome has a conventional beveled tip with a 90-degree bend and a main shaft curved at a radius of 14.5 mm. When attached to a syringe this cystotome allows the surgeon a more comfortable holding position during the capsulotomy procedure. PMID:2355328

  8. Maximal mydriasis evaluation in cataract surgery

    Directory of Open Access Journals (Sweden)

    Ho Tony

    1992-01-01

    Full Text Available We propose the Maximal Mydriasis Test (MMT as a simple and safe means to provide the cataract surgeon with objective and dependable pre-operative information on the idiosyncratic mydriatic response of the pupil. The MMT results of a consecutive series of 165 eyes from 100 adults referred for cataract evaluation are presented to illustrate its practical applications and value. The results of the MMT allows the surgeon to anticipate problem eyes pre-operatively so that he can plan his surgical strategy more appropriately and effectively. Conversely, the surgeon can also appropriately and confidently plan surgical procedures where wide pupillary dilation is important. The MMT has also helped improve our cost-effectiveness by cutting down unnecessary delays in the operating room and enabling better utilisation of restricted costly resources.

  9. A novel mechanism of hippocampal LTD involving muscarinic receptor-triggered interactions between AMPARs, GRIP and liprin-α

    Directory of Open Access Journals (Sweden)

    Dickinson Bryony A

    2009-06-01

    Full Text Available Abstract Background Long-term depression (LTD in the hippocampus can be induced by activation of different types of G-protein coupled receptors, in particular metabotropic glutamate receptors (mGluRs and muscarinic acethycholine receptors (mAChRs. Since mGluRs and mAChRs activate the same G-proteins and isoforms of phospholipase C (PLC, it would be expected that these two forms of LTD utilise the same molecular mechanisms. However, we find a distinct mechanism of LTD involving GRIP and liprin-α. Results Whilst both forms of LTD require activation of tyrosine phosphatases and involve internalisation of AMPARs, they use different molecular interactions. Specifically, mAChR-LTD, but not mGluR-LTD, is blocked by peptides that inhibit the binding of GRIP to the AMPA receptor subunit GluA2 and the binding of GRIP to liprin-α. Thus, different receptors that utilise the same G-proteins can regulate AMPAR trafficking and synaptic efficacy via distinct molecular mechanisms. Conclusion Our results suggest that mAChR-LTD selectively involves interactions between GRIP and liprin-α. These data indicate a novel mechanism of synaptic plasticity in which activation of M1 receptors results in AMPAR endocytosis, via a mechanism involving interactions between GluA2, GRIP and liprin-α.

  10. Measuring aniseikonia using scattering filters to simulate cataract

    Science.gov (United States)

    Wilson, Jason

    2011-12-01

    The relationship between anisometropia and aniseikonia (ANK) is not well understood. Ametropic cataract patients provide a unique opportunity to study this relationship after undergoing emmetropizing lens extraction. Because light scatter may affect ANK measurement in cataract patients, its effect should also be evaluated. The Basic Aniseikonia Test (BAT) was evaluated using afocal size lenses to produce specific changes in retinal height. Several light scattering devices were then evaluated to determine which produced effects most similar to cataract. Contrast sensitivity and visual acuity (VA) losses were measured with each device and compared to those reported in cataract. After determining the most appropriate light scattering device, twenty healthy patients with normal visual function were recruited to perform the BAT using the filters to simulate cataract. Cataract patients were recruited from Vision America and the University of Alabama at Birmingham School of Optometry. Patients between 20 and 75 years of age with at least 20/80 VA in each eye, ≥ 2D ametropia, and normal binocular function were recruited. Stereopsis and ANK were tested and each patient completed a symptom questionnaire. ANK measurements using afocal size lenses indicated that the BAT underestimates ANK, although the effect was minimal for vertical targets and darkened surroundings, as previously reported. Based on VA and contrast sensitivity loss, Vistech scattering filters produced changes most similar to cataract. Results of the BAT using Vistech filters demonstrated that a moderate cataract but not a mild cataract may affect the ANK measurement. ANK measurements on cataract patients indicated that those with ≥ 2 D ametropia in each eye may suffer from induced ANK after the first cataract extraction. With upcoming healthcare reform, unilateral cataract extraction may be covered, but not necessarily bilateral, depending on patient VA in each eye. However, a questionnaire about symptoms

  11. A PROSPECTIVE STUDY OF TRAUMATIC CATARACT AND ITS VISUAL OUTCOME

    Directory of Open Access Journals (Sweden)

    Siddharam S

    2014-06-01

    Full Text Available : INTRODUCTION: Ocular trauma is the leading cause of unilateral blindness all over the world.[1] The incidence of ocular trauma varies in different parts of the world. From India, the reported incidence is 20.53%.[2] Any strategy for prevention requires knowledge of the cause of injury, which may enable more appropriate targeting of resources towards preventing such injuries.[3] Eye trauma represents a large, potentially preventable burden on both victims and society as a whole. Traumatic cataracts occur secondary to blunt or penetrating ocular trauma, Infrared energy (glass-blower's cataract, electric shock and ionizing radiation are other rare causes of traumatic cataracts.[4] It form a separate category of cataracts as they present with other ocular morbidity like corneal tears, iris injury, vitreous hemorrhage and retinal tears; and they are to some extent, preventable. The methods used to evaluate the visual outcome in eyes managed for traumatic cataracts and senile cataracts are similar, but the damage to other ocular tissues owing to trauma may compromise the visual gain in eyes treated surgically for traumatic cataracts.[5] Hence, the success rates may differ between eyes with these two types of cataract. The aim of this study was to evaluate the final visual outcome of a patient with surgical extraction of traumatic cataract along with demographic features and modes of trauma.

  12. Assessing the elasticity change of cataract lens with OCE

    Science.gov (United States)

    Wu, Chen; Liu, Chih-Hao; Raghunathan, Raksha; Singh, Manmohan; Li, Jiasong; Han, Zhaolong; Larin, Kirill V.

    2016-03-01

    Cataract is one of the most common degenerative diseases that causes blindness. Careful quantification of lens biomechanical properties can greatly assist in early detection of the disease as well as personalization of treatment procedures. In this study, we utilize a phase-sensitive optical coherence elastography (OCE) system to assess the effects of the cold cataract on the biomechanical properties of porcine crystalline lens in vitro. Relaxation rates of air puff induced elastic waves were measured on the same crystalline lens with and without cold cataract. Results demonstrate that the relaxation rate and, thus, associated elasticity of the porcine lens, increased due to the presence of cold cataract.

  13. Control of astigmatism in cataract surgery.

    OpenAIRE

    Brown, N. A.; Sparrow, J M

    1988-01-01

    A study is reported on cataract surgery, with intraocular lens implant, with measurement of the preoperative astigmatism and of the postoperative astigmatism over 28 weeks. Nine interrupted 10/0 nylon sutures are used to close a limbal section. Preoperative astigmatism is compensated for in the method of suturing by the placement of additional sutures. Postoperatively sutures are cut in line with the plus cylinder axis in eyes showing excessive astigmatism with the rule. Final postoperative a...

  14. Sensory exotropia subsequent to senile cataract

    OpenAIRE

    Lou, Ding-hua; Xu, Ye-sheng; Yu-min LI

    2005-01-01

    To evaluate the phacoemulsification and intraocular lens implantation in patients with sensory exotropia subsequent to senile cataract. The authors prospectively studied the role of phacoemulsification and intraocular lens implantation on 25 patients by observing visual acuity, ocular alignment, binocular vision and diplopia pre-, 1 month post- and 3 months post-operation. The patients underwent follow-up for three months. Postoperatively, one patient had a corrected visual acuity of 20/50, a...

  15. Intraocular eyelash after uneventful cataract surgery

    OpenAIRE

    Knyazer, Boris

    2010-01-01

    Boris Knyazer, Jaime Levy, Itamar Klemperer, Tova LifshitzDepartment of Ophthalmology, Soroka University Medical Center, Ben-Gurion, University of the Negev, Beer-Sheva, IsraelIntroduction: Intraocular eyelash is an uncommon complication after cataract surgery. We report a very rare case of corneal foreign body after uneventful phacoemulsification surgery. Methods: A 66-year-old man referred to our outpatient ophthalmology clinic for routine examination one week after uneventful phacoemulsifi...

  16. MANUAL SMALL INCISION CATARACT SURGERY (MSICS)

    OpenAIRE

    Mishra,, A.N.; Manavalan; Ramya; Jeevitha; Vinnarasi; Latha; Sridevi; Parth

    2014-01-01

    : In developing country like India, the primary goal is to provide all the benefits to common man at minimal possible cost in visual rehabilitation of cataract. In achieving this goal, the surgery (MICS) described in this article can be extremely helpful. It has almost all the advantages of phacoemulsification, at the same time it is inexpensive. The wound construction, various techniques of nucleus delivery in MSICS are described precisely. This may stimulate the reader towar...

  17. Cataract influence on iris recognition performance

    Science.gov (United States)

    Trokielewicz, Mateusz; Czajka, Adam; Maciejewicz, Piotr

    2014-11-01

    This paper presents the experimental study revealing weaker performance of the automatic iris recognition methods for cataract-affected eyes when compared to healthy eyes. There is little research on the topic, mostly incorporating scarce databases that are often deficient in images representing more than one illness. We built our own database, acquiring 1288 eye images of 37 patients of the Medical University of Warsaw. Those images represent several common ocular diseases, such as cataract, along with less ordinary conditions, such as iris pattern alterations derived from illness or eye trauma. Images were captured in near-infrared light (used in biometrics) and for selected cases also in visible light (used in ophthalmological diagnosis). Since cataract is a disorder that is most populated by samples in the database, in this paper we focus solely on this illness. To assess the extent of the performance deterioration we use three iris recognition methodologies (commercial and academic solutions) to calculate genuine match scores for healthy eyes and those influenced by cataract. Results show a significant degradation in iris recognition reliability manifesting by worsening the genuine scores in all three matchers used in this study (12% of genuine score increase for an academic matcher, up to 175% of genuine score increase obtained for an example commercial matcher). This increase in genuine scores affected the final false non-match rate in two matchers. To our best knowledge this is the only study of such kind that employs more than one iris matcher, and analyzes the iris image segmentation as a potential source of decreased reliability

  18. Stabilisation of refraction following extracapsular cataract extraction.

    OpenAIRE

    Baranyovits, P.

    1990-01-01

    Regular serial refraction was used to determine the rate of stabilisation of refraction following routine extracapsular cataract surgery in 85 eyes. Patients were divided into four groups depending on wound closure technique: limbal section closed by interrupted 8-0 virgin silk, 9-0 polydioxanone or 10-0 nylon sutures, and corneal section closed by continuous 10-0 nylon suture. Stabilisation of refraction, sufficient to prescribe satisfactory glasses, occurred at three months except in the in...

  19. Cataract surgery in Fuchs' heterochromic iridocyclitis.

    OpenAIRE

    Sherwood, D. R.; Rosenthal, A R

    1992-01-01

    Eighteen eyes in 17 patients with Fuchs' heterochromic iridocyclitis underwent cataract extraction with or without intraocular lens implantation (17 extracapsular and one intracapsular). Intraoperative complications included hyphaema, poor pupillary dilatations, and localised zonule dehiscence with vitreous loss. Only four eyes developed a marked anterior uveitus (two pseudophakic and two aphakic) which resolved within 2 weeks with topical steroids. Three eyes developed a rise in intraocular ...

  20. Vitamin D deficiency and posterior subcapsular cataract

    OpenAIRE

    Brown, Craig

    2015-01-01

    Craig J Brown,1 Faical Akaichi21The Eye Center, Fayetteville, AR, USA; 2Scotland’s Rural College, Edinburgh, UKPurpose: To evaluate risk factors associated with posterior subcapsular cataract (PSC) development and the relationship between vitamin D deficiency and etiology of PSC.Methods: Of 195 consecutive patients from a private ophthalmology practice, diagnosed with PSC, serum vitamin D3 (25-OH D) levels were obtained for 175, and associations among risk factors, comorbidities, an...

  1. Vitamin D deficiency and posterior subcapsular cataract

    OpenAIRE

    Brown CJ; Akaichi F

    2015-01-01

    Craig J Brown,1 Faical Akaichi21The Eye Center, Fayetteville, AR, USA; 2Scotland’s Rural College, Edinburgh, UKPurpose: To evaluate risk factors associated with posterior subcapsular cataract (PSC) development and the relationship between vitamin D deficiency and etiology of PSC.Methods: Of 195 consecutive patients from a private ophthalmology practice, diagnosed with PSC, serum vitamin D3 (25-OH D) levels were obtained for 175, and associations among risk factors, comorbidities, and PS...

  2. Posterior lens capsule abscess due to Propionibacterium acnes and Staphylococcus epidermidis following extracapsular cataract extraction.

    OpenAIRE

    Manners, R M; Canning, C R

    1991-01-01

    A case of posterior lens capsular abscess occurring many months after an extracapsular cataract extraction is presented. This was caused by a mixed infection involving Propionibacterium acnes and Staphylococcus epidermidis. The significance of Staph epidermidis after such a long postoperative period is uncertain, but the case shows features typical of secondary endophthalmitis due to P acnes, including a long delay in onset and a grumbling course not brought under control by medical treatment...

  3. Contribution of Cholesterol and Oxysterols in the Physiopathology of Cataract: Implication for the Development of Pharmacological Treatments

    Directory of Open Access Journals (Sweden)

    Anne Vejux

    2011-01-01

    Full Text Available The development of cataract is associated with some lipid changes in human lens fibers, especially with increased accumulation and redistribution of cholesterol inside these cells. Some direct and indirect lines of evidence, also suggest an involvement of cholesterol oxide derivatives (also named oxysterols in the development of cataract. Oxysterol formation can result either from nonenzymatic or enzymatic processes, and some oxysterols can induce a wide range of cytotoxic effects (overproduction of reactive oxygen species (ROS; phospholipidosis which might contribute to the initiation and progression of cataract. Thus, the conception of molecules capable of regulating cholesterol homeostasia and oxysterol levels in human lens fibers can have some interests and constitute an alternative to surgery at least at early stages of the disease.

  4. Hollow needle cataract aspiration in antiquity.

    Science.gov (United States)

    Pérez-Cambrodí, Rafael J; Ascaso, Francisco J; Diab, Fathi; Alzamora-Rodríguez, Antonio; Grzybowski, Andrzej

    2015-12-01

    The dislocation of the crystalline lens or couching technique was the predominant procedure to surgically remove cataracts until the 18th century A.D. However, in the Middle Ages, some Arab physicians tried to aspirate the opaque lens by means of a glass tube following a paracentesis. Some literary sources attributed the origins of this technique to Antyllus of Alexandria, a Greek surgeon who lived in the 2nd century A.D. in the Roman Empire. Nevertheless, this statement remains unclear and is probably the consequence of posterior interpretations or incorrect translations of the manuscripts. In recent years, the discovery of the hollow needles from Montbellet (France) and Viladamat (Spain), in archaeological settlements dated between the 1st century and 3rd century A.D., has reopened the possibility of cataract extraction as an option in the surgical management of soft cataracts in the antiquity. In any case, these findings are exceptional, and thus, probably this technique was not widely practised and very likely disparaged by the medical community. PMID:26385516

  5. Capsulotomy for phacoemulsification in hypermature cataracts.

    Science.gov (United States)

    Vajpayee, R B; Angra, S K; Honavar, S G; Katoch, S; Prasad, N; Bansal, A; Anand, J

    1995-11-01

    We describe a modified surgical technique of anterior capsulotomy and phacoemulsification for use in hypermature cataracts. Surgical steps included inferior linear capsulotomy with aspiration of milky cortex, inflation of the capsular sac with viscoelastic, a reverse triangular anterior capsulotomy with Vannas scissors, and in-the-bag bimanual sculpting of the nucleus. An oval 5 mm x 6 mm posterior chamber intraocular lens was used with single horizontal or no-stitch wound closure. The technique was used successfully in 20 cases of hypermature cataract. The mean time required to perform phacoemulsification was 3.46 minutes (range 1.2 to 6.3 minutes), with a standard deviation of 1.29. Visual acuity on the first postoperative day ranged from 20/20 to 20/60 (median 20/40). At one week, the mean astigmatism was 1.01 diopters (range 0.25 to 2.75 diopters). The mean endothelial cell loss was 13% (range 3.6% to 26.0%). Based on our results, the modified phacoemulsification technique merits consideration for use in hypermature cataracts. PMID:8551435

  6. Incidence and Characteristics of Cataract Surgery in France from 2009 to 2012 : Incidence and characteristics of cataract surgery

    OpenAIRE

    Daien, Vincent; Le Pape, Annick; Hève, Didier; Carriere, Isabelle; Villain, Max

    2015-01-01

    Objective: To report age- and sex-specific incidence rates of cataract surgery in France and evaluate the trends of cataract surgery from 2009 to 2012. Design: Cohort study Subjects: Data for all patients who underwent primary cataract surgery in France between January 2009 and December 2012 were collected from the national database. Methods: Annual incidence rates were calculated and adjusted to the corresponding-year national population data from the French national institute of statistics....

  7. Combined 23-gauge transconjunctival sutureless vitrectomy and cataract surgery in cases with cataract and posterior segment diseases

    OpenAIRE

    Yazici Ahmet; Kara Necip; Bozkurt Ercument; Cakir Mehmet; Goker Hasan; Demirok Ahmet; Yilmaz Omer

    2010-01-01

    Background: Combined cataract surgery and transconjunctival sutureless vitrectomy are a good option in patients with cataract and vitreoretinal diseases. Aim: To evaluate the effectiveness, outcomes, and complications of combined 23-gauge transconjunctival sutureless vitrectomy and cataract surgery. Settings and Design: A retrospective case series was conducted at the Beyoglu Eye Education and Research Hospital. Materials and Methods: In this study, 28 eyes of 28 patients underwent combine...

  8. Involvement of mast cells and proteinase-activated receptor 2 in oxaliplatin-induced mechanical allodynia in mice.

    Science.gov (United States)

    Sakamoto, Ayumi; Andoh, Tsugunobu; Kuraishi, Yasushi

    2016-03-01

    The chemotherapeutic agent oxaliplatin induces neuropathic pain, a dose-limiting side effect, but the underlying mechanisms are not fully understood. Here, we show the potential involvement of cutaneous mast cells in oxaliplatin-induced mechanical allodynia in mice. A single intraperitoneal injection of oxaliplatin induced mechanical allodynia, which peaked on day 10 after injection. Oxaliplatin-induced mechanical allodynia was almost completely prevented by congenital mast cell deficiency. The numbers of total and degranulated mast cells was significantly increased in the skin after oxaliplatin administration. Repetitive topical application of the mast cell stabilizer azelastine hydrochloride inhibited mechanical allodynia and the degranulation of mast cells without affecting the number of mast cells in oxaliplatin-treated mice. The serine protease inhibitor camostat mesilate and the proteinase-activated receptor 2 (PAR2) antagonist FSLLRY-NH2 significantly inhibited oxaliplatin-induced mechanical allodynia. However, it was not inhibited by the H1 histamine receptor antagonist terfenadine. Single oxaliplatin administration increased the activity of cutaneous serine proteases, which was attenuated by camostat and mast cell deficiency. Depletion of the capsaicin-sensitive primary afferents by neonatal capsaicin treatment almost completely prevented oxaliplatin-induced mechanical allodynia, the increase in the number of mast cells, and the activity of cutaneous serine proteases. These results suggest that serine protease(s) released from mast cells and PAR2 are involved in oxaliplatin-induced mechanical allodynia. Therefore, oxaliplatin may indirectly affect the functions of mast cells through its action on capsaicin-sensitive primary afferents. PMID:26804251

  9. Rapid, Opioid-sensitive Mechanisms Involved in Transient Receptor Potential Vanilloid 1 Sensitization*S⃞

    OpenAIRE

    Vetter, Irina; Cheng, Wei; Peiris, Madusha; Wyse, Bruce D; Sarah J. Roberts-Thomson; Zheng, Jie; Monteith, Gregory R.; Cabot, Peter J.

    2008-01-01

    TRPV1 is a nociceptive, Ca2+-selective ion channel involved in the development of several painful conditions. Sensitization of TRPV1 responses by cAMP-dependent PKA crucially contributes to the development of inflammatory hyperalgesia. However, the pathways involved in potentiation of TRPV1 responses by cAMP-dependent PKA remain largely unknown. Using HEK cells stably expressing TRPV1 and the μ opioid receptor, we demonstrated that treatment with the adenylate cyclase ...

  10. Adult criminal involvement: A cross-sectional inquiry into correlates and mechanisms over the life course

    OpenAIRE

    DePadilla, Lara; Perkins, Molly M.; Elifson, Kirk W.; Sterk, Claire E.

    2012-01-01

    In this paper, we examine the relative contribution of four domains of predictors that have been linked to adult criminal involvement: (1) socio-demographic characteristics, (2) family-of-origin factors, (3) proximal processes developed during adolescence, and (4) current lifestyle and situational factors. Cross-sectional data were collected through face-to-face interviews with 242 community-recruited adults. Data analysis involved negative binomial regression. Being male, f...

  11. Fatty-acid metabolism is involved in stress-resistance mechanisms of Caenorhabditis elegans

    OpenAIRE

    Horikawa, Makoto; Sakamoto, Kazuichi

    2009-01-01

    Fatty acids are the major components of the phospholipid bilayer and are involved in several functions of cell membrane. We previously reported that fatty-acid metabolism is involved in the regulation of DAF-2/insulin signal in Caenorhabditis elegans. In this study, we investigate the role of fatty-acid metabolism in stress resistance with respect to daf-16 in nematode. We found that fatty-acid metabolism regulates heat, osmotic, and oxidative-stress resistance in C. elegans. RNA interference...

  12. Manual suture less small incision cataract surgery in patients with uveitic cataract

    Directory of Open Access Journals (Sweden)

    Rahul Bhargava

    2014-01-01

    Conclusion: SICS with posterior chamber intraocular lens implantation is safe in most cataracts due to uveitis and improves BCVA at 6 months. Inflammation should be well-controlled pre-operatively for at least 3 months. Posterior capsule opacification, macular edema and persistent uveitis were the main factors affecting visual outcome. SICS requires minimal instrumentation, surgical time is short and can also be performed in rural clinics and eye-camps, where phacoemulsification machines are unavailable. SICS may be a more practical and cost-effective technique for uveitic cataract, in such circumstances.

  13. Risk of endophthalmitis after cataract extraction: results from the International Cataract Surgery Outcomes study

    OpenAIRE

    Norregaard, J. C.; Thoning, H.; Bernth-Petersen, P.; Andersen, T. F.; Javitt, J.; G. Anderson

    1997-01-01

    AIM—To estimate risk of infectious endophthalmitis after cataract extraction in Denmark and to compare results with the risk of this complication in the USA
METHODS—In the national Danish administrative hospital register, 19 426 patients were identified who underwent first eye cataract surgery from 1985 to 1987 and who were 50 years of age or older. Of these, 61 patients had postoperative endophthalmitis.
RESULTS—A 12 month cumulative risk of rehospitalisation for endophthalmitis was estimate...

  14. Involvement of a glibenclamide-sensitive mechanism in the nitrergic neurotransmission of the pig intravesical ureter

    Science.gov (United States)

    Hernández, Medardo; Prieto, Dolores; Orensanz, Luis M; Barahona, María Victoria; Jiménez-Cidre, Miguel; Rivera, Luis; García-Sacristán, Albino; Simonsen, Ulf

    1997-01-01

    The present study was designed to investigate whether potassium (K+) channels are involved in the relaxations to nitric oxide (NO) of pig intravesical ureteral preparations suspended in organ baths for isometric tension recordings. In ureteral strips treated with guanethidine (10−5 M) and atropine (10−7 M) to block adrenergic neurotransmission and muscarinic receptors, respectively, NO was either released from nitrergic nerves by electrical field stimulation (EFS, 0.5–10 Hz, 1 ms duration, 20 s trains), or exogenously-applied as an acidified solution of sodium nitrite (NaNO2, 10−6–10−3 M).Incubation with an inhibitor of guanylate cyclase activation by NO, methylene blue (10−5 M) did not change the basal tension of intravesical ureteral strips but inhibited the relaxation induced by EFS or exogenous NO on ureteral preparations contracted with the thromboxane analogue U46619 (10−7 M).Incubation with charybdotoxin (3×10−8 M) and apamin (5×10−7 M), which are inhibitors of large and small conductance calcium (Ca2+)-activated K+ channels, respectively, did not modify basal tension or the relaxations induced by EFS and exogenous NO. Treatment with charybdotoxin or apamin plus methylene blue (10−5 M) significantly reduced the relaxations to EFS and exogenous NO. However, in both cases the reductions were similar to the inhibition evoked by methylene blue alone. The combined addition of charybdotoxin plus apamin did not change the relaxations to EFS or exogenously added NO of the porcine intravesical ureter.Cromakalim (10−8–3×10−6 M), an opener of ATP-sensitive K+ channels, evoked a dose-dependent relaxation with a pD2 of 7.3±0.2 and maximum relaxant effect of a 71.8±4.2% of the contraction induced by U46619 in the pig intravesical ureter. The blocker of ATP-sensitive K+ channels, glibenclamide (10−6 M), inhibited markedly the relaxations to cromakalim.Glibenclamide (10−6 M) had no effect on the basal tone of

  15. Purely Mechanical Memristors: Perfect Massless Memory Resistors, the Missing Perfect Mass-Involving Memristor, and Massive Memristive Systems

    OpenAIRE

    Vongehr, Sascha

    2015-01-01

    We define a mechanical analog to the electrical basic circuit element M = d{\\phi}/dQ, namely the ideal mechanical memristance M = dp/dx; p is momentum. We then introduce a mechanical memory resistor which has M(x) independent of velocity v, so it is a perfect (= not-just-memristive) memristor, although its memristance does not crucially involve inert mass. It is practically realizable with a 1cm radius hollow sphere in heavy fuel oil with a temperature gradient. It has a pinched hysteretic lo...

  16. Swarming mechanisms in the yellow fever mosquito: aggregation pheromones involved in the mating behavior of Aedes aegypti

    Science.gov (United States)

    Mosquitoes of various species mate in swarms comprised of tens to thousands flying males. Yet little information is known about mosquito swarming mechanism. Discovering chemical cues involved in mosquito biology leads to better adaptation of disease control interventions. In this study, we aimed ...

  17. Study of the Chemical Mechanism Involved in the Formation of Tungstite in Benzyl Alcohol by the Advanced QEXAFS Technique

    DEFF Research Database (Denmark)

    Olliges‐Stadler, Inga; Stötzel, Jan; Koziej, Dorota;

    2012-01-01

    Insight into the complex chemical mechanism for the formation of tungstite nanoparticles obtained by the reaction of tungsten hexachloride with benzyl alcohol is presented herein. The organic and inorganic species involved in the formation of the nanoparticles were studied by time‐dependent gas c...

  18. Molecular mechanism for the involvement of nuclear receptor FXR in HBV-associated hepatocellular carcinoma

    Directory of Open Access Journals (Sweden)

    Yong-dong Niu

    2011-08-01

    Full Text Available Farnesoid X receptor (FXR, also termed nuclear receptor NR1H4 is critically involved in the regulation of nascent bile formation and bile acid enterohepatic circulation. FXR and bile acids have been shown to play roles in liver regeneration and inflammatory responses. There is increasing evidence suggesting that FXR and the FXR signaling pathway are involved in the pathophysiology of a wide range of liver diseases, such as viral hepatitis, cirrhosis, and hepatocellular carcinoma (HCC. Here we discuss the latest discoveries of FXR functions with relevance to bile acid metabolism and HBV-associated HCC. More specifically, the goal of this review is to discuss the roles of FXR and bile acids in regulating HBV replication and how disregulation of the FXR-bile acid signaling pathway is involved in HBV-associated hepatocarcinogenesis.

  19. A Mechanism for Land-Atmosphere Feedback Involving Planetary Wave Structures

    Science.gov (United States)

    Koster, Randal D.; Chang, Yehui; Schubert, Siegfried D.

    2014-01-01

    While the ability of land surface conditions to influence the atmosphere has been demonstrated in various modeling and observational studies, the precise mechanisms by which land-atmosphere feedback occurs are still largely unknown particularly the mechanisms that allow land moisture state in one region to affect atmospheric conditions in another. Such remote impacts are examined here in the context of atmospheric general circulation model (AGCM) simulations, leading to the identification of one potential mechanism: the phase-locking and amplification of a planetary wave through the imposition of a spatial pattern of soil moisture at the land surface. This mechanism, shown here to be relevant in the AGCM, apparently also operates in nature, as suggested by supporting evidence found in reanalysis data.

  20. Molecules and mechanisms involved in the generation and migration of cortical interneurons

    Directory of Open Access Journals (Sweden)

    Luis R Hernández‑Miranda

    2010-03-01

    Full Text Available The GABA (γ-aminobutyric acid-containing interneurons of the neocortex are largely derived from the ganglionic eminences in the subpallium. Numerous studies have previously defined the migratory paths travelled by these neurons from their origins to their destinations in the cortex. We review here results of studies that have identified many of the genes expressed in the subpallium that are involved in the specification of the subtypes of cortical interneurons, and the numerous transcription factors, motogenic factors and guidance molecules that are involved in their migration.

  1. Attentional Biases toward Attractive Alternatives and Rivals: Mechanisms Involved in Relationship Maintenance among Chinese Women

    OpenAIRE

    Ma, Yidan; Zhao, Guang; Tu, Shen; Zheng, Yong

    2015-01-01

    A long-term romantic relationship can offer many benefits to committed individuals. Thus, humans possess relationship maintenance mechanisms to protect against threats from those who serve as attractive alternatives or intrasexual rivals. Many studies have indicated that romantic love can act as a commitment device to activate these mechanisms. To examine the attentional bias associated with relationship maintenance among 108 college students (49 single and 59 committed females) in China, we ...

  2. A conflict monitoring account of the control mechanisms involved in dual-tasking

    OpenAIRE

    Olszanowski, Michal; Bajo, Maria Teresa; Szmalec, Arnaud

    2015-01-01

    The present study investigates the cognitive mechanism underlying the control of interference during dual-task coordination. Partially inspired by the Conflict Monitoring Hypothesis (Botvinick et al., 2001), we test the assumption that dual-task interference is resolved by a top-down adaptation mechanism that is responsible for behavioral adjustments in the prioritization of the coordinated tasks. In a series of two experiments, we measured conflict adaptation to the so-called Gratton effect—...

  3. Self-assembly of protein aggregates in ageing disorders: the lens and cataract model

    OpenAIRE

    Clark, John I.

    2013-01-01

    Cataract, neurodegenerative disease, macular degeneration and pathologies of ageing are often characterized by the slow progressive destabilization of proteins and their self-assembly to amyloid-like fibrils and aggregates. During normal cell differentiation, protein self-assembly is well established as a dynamic mechanism for cytoskeletal organization. With the increased emphasis on ageing disorders, there is renewed interest in small-molecule regulators of protein self-assembly. Synthetic p...

  4. Natural flavonoids as potential multifunctional agents in prevention of diabetic cataract

    OpenAIRE

    Stefek, Milan

    2011-01-01

    Cataract is one of the earliest secondary complications of diabetes mellitus. The lens is a closed system with limited capability to repair or regenerate itself. Current evidence supports the view that cataractogenesis is a multifactorial process. Mechanisms related to glucose toxicity, namely oxidative stress, processes of non-enzymatic glycation and enhanced polyol pathway significantly contribute to the development of eye lens opacity under conditions of diabetes. There is an urgent need f...

  5. Sensitizing Children to the Social and Emotional Mechanisms Involved in Racism: A Program Evaluation

    Science.gov (United States)

    Triliva, Sofia; Anagnostopoulou, Tanya; Vleioras, Georgios

    2014-01-01

    This paper describes and discusses the results of an intervention aiming to sensitize children to the social and emotional processes involved in racism. The intervention was applied and evaluated in 10 Greek elementary schools. The goals and the intervention methods of the program modules are briefly outlined and the results of the program…

  6. Barriers to cataract surgery in Africa: A systematic review

    Directory of Open Access Journals (Sweden)

    Shaheer Aboobaker

    2016-01-01

    Full Text Available Cataract remains the leading cause of blindness in Africa. We performed a systematic literature search of articles reporting barriers to cataract surgery in Africa. PubMed and Google Scholar databases were searched with the terms "barriers, cataract, Africa, cataract surgery, cataract surgical coverage (CSC, and rapid assessment of avoidable blindness (RAAB." The review covered from 1999 to 2014. In RAAB studies, barriers related to awareness and access were more commonly reported than acceptance. Other type of studies reported cost as the most common barrier. Some qualitative studies tended to report community and family dynamics as barriers to cataract surgery. CSC was lower in females in 88.2% of the studies. The variability in outcomes of studies of barriers to cataract surgery could be due to context and the type of data collection. It is likely that qualitative data will provide a deeper understanding of the complex social, family, community, financial and gender issues relating to barriers to uptake of cataract surgery in Africa.

  7. Antioxidant markers in human senile and diabetic cataract ous

    International Nuclear Information System (INIS)

    To determine the role of free radicals and antioxidant enzymes in patients suffering from cataract due to aging and diabetes. The study was conducted on 80 cataract patients. Lens and plasma samples from senile and diabetic subjects suffering from cataract were analyzed and activity of Cu, Zn-superoxide dismutase (Cu, Zn-SOD) was measured using xanthine oxidase system. Catalase (CAT) activity was estimated. Levels of malondialdehyde (MDA) was measured by thiobarbituric acid reaction. Student's t- test was employed for analysis of results. Significant difference (p<0.001) was found in activity of Cu, Zn-SOD in cataract lenses from diabetic patients as compared to senile subjects, CAT activities was also lower (p<0.001) in lenses from diabetic cataract patients when compared to lenses from senile cataractous subjects. Lens MDA levels were significantly higher (p<0.001) in cataract lenses from diabetic patients than in senile subjects. Plasma MDA levels were lowest (p<0.001) in controls as compared to senile and diabetic cataractous patients. (author)

  8. Congenital cataract screening in maternity wards is effective

    DEFF Research Database (Denmark)

    Magnusson, Gunilla; Bizjajeva, Svetlana; Haargaard, Birgitte; Lundström, Mats; Nyström, Alf; Tornqvist, Kristina

    2013-01-01

    screening policy. Response frequency was 96% (122/127). Data were derived from The Pediatric Cataract Register, PECARE Sweden. All Swedish children diagnosed with congenital cataract and operated on before 1 year of age between January 2007 and December 2009 were included. Statistical comparison with...

  9. Application of femtotechnologies and terahertz spectroscopy methods in cataract diagnostics

    Science.gov (United States)

    Sakhnov, S. N.; Leksutkina, E. V.; Smolyanskaya, O. A.; Usov, A. V.; Parakhuda, S. E.; Grachev, Ya. V.; Kozlov, S. A.

    2011-08-01

    We study the destructive action of femtosecond pulses (200 fs) on the human cataractous crystalline lens and the transmission of the cataractous lens in the terahertz spectral range of electromagnetic oscillations (0.2-1 THz) in relation to the density of the nucleus of the lens.

  10. [Diabetic cataract and flavonoids (first results) (author's transl)].

    Science.gov (United States)

    Leuenberger, P M

    1978-04-01

    The possible effects of Quercetine, a potent inhibitor of aldose-reductase, on cataract formation and vascular permeability were investigated in streptozotocine-diabetic rats. Preliminary results after peroral administration of Quercetine did not allow to demonstrate a clear inhibitory effect on cataract formation. PMID:418268

  11. BCR-ABL negative myeloproliferative neoplasia: a review of involved molecular mechanisms.

    Science.gov (United States)

    Koopmans, Suzanne M; Schouten, Harry C; van Marion, Ariënne M W

    2015-02-01

    The clonal bone marrow stem cell disorders essential thrombocythemia (ET), polycythemia vera (PV) and primary myelofibrosis (PMF) belong to the group of Philadelphia chromosome negative myeloproliferative neoplasia (Ph- MPN). In 2005 the JAK2(V617F) mutation was discovered which has generated more insight in the pathogenetic mechanism of the MPNs. More mutations have been detected in MPN patients since. However, the underlying cause of MPN has not been discovered so far. The mechanism of increased angiogenesis in MPNs and the development of fibrosis in the bone marrow in PMF patients and in some ET and PV patients is still not known. This review will focus on the most important molecular pathogenetic mechanisms in MPN patients. PMID:25196073

  12. The Role and Mechanisms of Action of Glucocorticoid Involvement in Memory Storage

    Directory of Open Access Journals (Sweden)

    Carmen Sandi

    1998-01-01

    integral aspect of the neurobiological mechanism underlying memory formation. By reviewing the work carried out in different learning models in chicks (passive avoidance learning and rats (spatial orientation in the Morris water maze and contextual fear conditioning, a role for brain corticosterone action through the glucocorticoid receptor type on the mechanisms of memory consolidation is hypothesized. Evidence is also presented to relate post-training corticosterone levels to the strength of memory storage. Finally, the possible molecular mechanisms that might mediate the influences of glucocorticoids in synaptic plasticity subserving long-term memory formation are considered, mainly by focusing on studies implicating a steroid action through (i glutamatergic transmission and (ii cell adhesion molecules.

  13. Congenital cataract. Report 2. Current strategies of congenital cataract management in children: a review

    OpenAIRE

    N. Ya. Senchenko; K. A. Nagaeva; E. K. Ayuyeva1; T.N. Iureva

    2014-01-01

    Different approaches to surgical and pleoptic treatment of congenital cataract and amblyopia of obscure origin in children are represented. Main tendencies that determine the indications to surgical procedures and their terms are described. Current techniques of aphakia correction, their advantages and disadvantages as well as pleoptic methods of visual system stimulation are discussed

  14. Tibolone protects astrocytic cells from glucose deprivation through a mechanism involving estrogen receptor beta and the upregulation of neuroglobin expression.

    Science.gov (United States)

    Avila-Rodriguez, Marco; Garcia-Segura, Luis Miguel; Hidalgo-Lanussa, Oscar; Baez, Eliana; Gonzalez, Janneth; Barreto, George E

    2016-09-15

    Tibolone, a synthetic steroid used for the prevention of osteoporosis and the treatment of climacteric symptoms in post-menopausal women, may exert tissue selective estrogenic actions acting on estrogen receptors (ERs). We previously showed that tibolone protects human T98G astroglial cells against glucose deprivation (GD). In this study we have explored whether the protective effect of tibolone on these cells is mediated by ERs. Experimental studies showed that both ERα and ERβ were involved in the protection by tibolone on GD cells, being ERβ preferentially involved on these actions over ERα. Tibolone increased viability of GD cells by a mechanism fully blocked by an ERβ antagonist and partially blocked by an ERα antagonist. Furthermore, ERβ inhibition prevented the effect of tibolone on nuclear fragmentation, ROS and mitochondrial membrane potential in GD cells. The protective effect of tibolone was mediated by neuroglobin. Tibolone upregulated neuroglobin in T98G cells and primary mouse astrocytes by a mechanism involving ERβ and neuroglobin silencing prevented the protective action of tibolone on GD cells. In summary, tibolone protects T98G cells by a mechanism involving ERβ and the upregulation of neuroglobin. PMID:27250720

  15. Mechanisms involved in the evasion of the host defence by Pseudomonas aeruginosa

    DEFF Research Database (Denmark)

    Kharazmi, A

    1991-01-01

    Pseudomonas aeruginosa, an extracellular opportunistic pathogen, utilizes two major mechanisms to evade the host defence system. One of these mechanisms is the production of a large number of extracellular products, such as proteases, toxins, and lipases. The two proteases, alkaline protease and...... elastase, inhibit the function of the cells of the immune system (phagocytes, NK cells, T cells), inactivate several cytokines (IL-1, IL-2, IFN-r, TNF), cleave immunoglobulins and inactivate complement. Inhibition of the local immune response by bacterial proteases provides an environment for the...

  16. The laparotomy incision: a technique to facilitate capsulorhexis in microincision cataract surgery.

    Science.gov (United States)

    O'Connor, Jeremy C; O'Connell, Eamon D; Sciscio, Andrea; Mulhern, Mark G

    2008-01-01

    Microincision cataract surgery is a new technique in the development of cataract surgery and is not without difficulties. Creation of the continuous curvilinear capsulorhexis as performed in conventional coaxial phacoemulsification surgery does not apply as readily. The authors describe a method for initiating the continuous curvilinear capsulorhexis (the laparotomy incision) using only an inexpensive 25-gauge bent needle cystototome. The technique involves a long linear incision in the anterior capsule down the belly of the lens as a means of initiating the capsulorhexis. Advantages of the technique include the creation of a large capsular flap, which allows easier completion of the continuous curvilinear capsulorhexis through a smaller range of movement, avoiding "oar locking" in the small incision and creation of striae in the cornea. It also allows better maintenance of anterior chamber depth, minimizing risk of radial tears. PMID:19065989

  17. VIGS for dissecting mechanisms involved in the symbiotic interaction of microbes with plants

    DEFF Research Database (Denmark)

    Grønlund, Mette

    Virus-induced gene silencing (VIGS) is an alternative reverse genetics tool for silencing of genes in some plants which are difficult to transform. The pea early browning virus (PEBV) has been developed as a VIGS vector and used in pea for functional analysis of several genes. Here, a PEBV-VIGS p......-VIGS protocol is described which is suitable for reverse genetics studies in pea for genes involved in the symbiosis with arbuscular mycorrhizal fungi and Rhizobium....

  18. Study of the effects of dietary polyunsaturated fatty acids: Molecular mechanisms involved intestinal inflammation

    Energy Technology Data Exchange (ETDEWEB)

    Knoch, B.; Barnett, M. P. G.; Roy, N. C.; McNabb, W. C.

    2009-07-01

    The use of omics techniques in combination with model systems and molecular tools allows to understand how foods and food components act on metabolic pathways to regulate transcriptional processes. Polyunsaturated fatty acids have distinctive nutritional and metabolic effects because they give rise to lipid mediated products and affect the expression of various genes involved in intestinal inflammation. The present review focuses on the molecular effects of dietary polyunsaturated fatty acids on intestinal inflammation. (Author) 74 refs.

  19. Understanding the molecular mechanisms involved in the interfacial self-healing of supramolecular rubbers

    NARCIS (Netherlands)

    Bose, R.K.; Garcia Espallargas, S.J.; Van der Zwaag, S.

    2013-01-01

    Supramolecular rubbers based on 2-aminoethylimidazolidone and fatty acids with epoxy crosslinks have been shown to self-heal via multiple hydrogen bonding sites. In this work, several tools are used to investigate the molecular mechanisms taking place at the interface to understand cohesive healing

  20. Different mechanisms are involved in the antibody mediated inhibition of ligand binding to the urokinase receptor

    DEFF Research Database (Denmark)

    List, K; Høyer-Hansen, G; Rønne, E;

    1999-01-01

    Certain monoclonal antibodies are capable of inhibiting the biological binding reactions of their target proteins. At the molecular level, this type of effect may be brought about by completely different mechanisms, such as competition for common binding determinants, steric hindrance or...

  1. Cataract extraction in eyes filled with silicone oil.

    Science.gov (United States)

    Moisseiev, J; Bartov, E; Cahane, M; Blumenthal, M; Treister, G

    1992-11-01

    A surgical technique for cataract extraction in eyes filled with silicone oil was developed that has two major objectives: removal of the entire cataractous lens and complete preservation of the silicone oil volume. A regular extracapsular cataract extraction or phacoemulsification is performed, and the incision is closed with the final sutures. All steps are performed under continuous positive pressure achieved with an anterior chamber maintainer connected to a bottle of balanced saline solution. An inferior basal iridectomy is created with a vitrectomy probe, and the posterior capsule is then slowly pulled out through the limbal incision with intraocular forceps, again under positive pressure, in an eye that is actually a closed system, without any loss of silicone. This step results in transformation of the extracapsular cataract extraction condition into an intracapsular cataract extraction condition. The described technique was successfully performed in nine eyes. In the younger patients, the whole procedure was completed through two very small limbal openings. PMID:1444927

  2. [Developments in modern cataract surgery – a critical overview].

    Science.gov (United States)

    Menapace, Rupert

    2016-01-01

    Cataract surgery has tremendously evolved in recent years. Innovations include micro-incision cataract surgery through incisions smaller than 2mm, high-fluidics phacoaspiration and laser phacoemulsification to minimize or replace the use of ultrasound, the advent of femtolasers for high-precision incisions in the cornea, the lens capsule and the cataractous lens, aspheric intraocular lenses (IOLs) to enhance the quality and contrast of the image, multifocal and enhanced-depth-of-focus IOLs to correct presbyopia, advancements in biometry and IOL power calculation, prevention of secondary capsule opacification by improvements in the design and material of the IOLs and surgical techniques like capsule polishing and posterior capsulorhexis, and pharmacological prophylaxis and possible future treatment of the cataract itself. Finally, cost-effectiveness and future potential of same-session bilateral cataract surgery are discussed. PMID:26982642

  3. Cataracts in retired actinide-exposed radiation workers

    International Nuclear Information System (INIS)

    Radiation-induced cataracts are predominantly of the posterior sub-capsular (PSC) type, whereas about 90% of age-related cataracts are of other types. Retired workers, likely to have transuranic body burdens, from three DOE-supported installations were questioned regarding their eye-care history and asked for permission to contact their eye-care providers regarding any cataracts. In 97 cases with lifetime exposure records 20 cases (20.6%) were reported to have PSC cataracts. However, of 24 individuals with recorded lifetime doses of 200-600 mSv, nine (37.5%) had PSC cataracts, compared with 15.1% of 73 cases with doses of less than 200 mSv. This difference is statistically significant at the 5% level. (authors)

  4. The genetic and molecular basis of congenital cataract

    Directory of Open Access Journals (Sweden)

    Alessandro Santana

    2011-04-01

    Full Text Available Congenital cataracts are one of the most treatable causes of visual impairment and blindness during infancy, with an estimated prevalence of 1 to 6 cases per 10,000 live births. Approximately fifty percent of all congenital cataract cases may have a genetic cause. All three types of Mendelian inheritance have been reported for cataract; however, autosomal dominant transmission seems to be the most frequent. The transparency and high refractive index of the lens are achieved by the precise architecture of the fiber cells and the homeostasis of the lens proteins in terms of their concentration, stability, and supramolecular organization. Research on hereditary congenital cataract led to the identification of several classes of candidate genes that encode proteins such crystallins, lens specific connexins, aquaporine, cytoskeletal structural proteins, and developmental regulators. The purpose of this study was to review the literature on the recent advances made in understanding the molecular genetic basis of congenital cataracts.

  5. Cataract extraction after brachytherapy for malignant melanoma of the choroid

    International Nuclear Information System (INIS)

    Thirteen eyes of 55 consecutive patients treated with brachytherapy for malignant melanoma of the choroid developed postirradiation cataracts. Cataract development was more common in older patients and in patients with larger and more anterior tumors. Eleven eyes had extracapsular cataract extraction and intraocular lens implantation. Initial visual improvement occurred in 91% of eyes, with an average improvement of 5.5 lines. Visual acuity was maintained at 20/60 or better in 55% of the eyes over an average period of follow-up of 24 months (range, 6 to 40 months). These data suggest that, visually, cataract extraction can be helpful in selected patients who develop a cataract after brachytherapy for malignant melanoma of the choroid

  6. Cataract extraction after brachytherapy for malignant melanoma of the choroid

    Energy Technology Data Exchange (ETDEWEB)

    Fish, G.E.; Jost, B.F.; Snyder, W.I.; Fuller, D.G.; Birch, D.G. (Texas Retina Associates, Dallas (USA))

    1991-05-01

    Thirteen eyes of 55 consecutive patients treated with brachytherapy for malignant melanoma of the choroid developed postirradiation cataracts. Cataract development was more common in older patients and in patients with larger and more anterior tumors. Eleven eyes had extracapsular cataract extraction and intraocular lens implantation. Initial visual improvement occurred in 91% of eyes, with an average improvement of 5.5 lines. Visual acuity was maintained at 20/60 or better in 55% of the eyes over an average period of follow-up of 24 months (range, 6 to 40 months). These data suggest that, visually, cataract extraction can be helpful in selected patients who develop a cataract after brachytherapy for malignant melanoma of the choroid.

  7. Ionizing radiation induced cataract; Katarakt-Induktion durch ionisierende Strahlung

    Energy Technology Data Exchange (ETDEWEB)

    Mueller, W.U. [Universitaetsklinikum Essen (Germany). Inst. fuer Medizinische Strahlenbiologie

    2013-07-01

    Until recently it was believed that the cataract (opacity of the eye lens) is a deterministic effect with a dose threshold of several Gray in dependence on the exposure conditions. Studies in Hiroshima and Nagasaki, in the vicinity of Chernobyl, of American radiologic technologists, astronauts, and patients after having received several computer tomographies of the head region, however, have shown that this assumption is not correct. It had been overlooked in the past that with decreasing dose the latency period is increasing. Therefore, the originally available studies were terminated too early. The more recent studies show that, in the case of a threshold existing at all, it is definitely below 0.8 Gy independently of an acute or a chronic exposure. All studies, however, include 0 Gy in the confidence interval, so that the absence of a dose threshold cannot be excluded. The German Commission on Radiological Protection (Strahlenschutzkommission, SSK) suggested therefore among others: targeted recording of the lens dose during activities which are known to be associated with possible significant lens exposure, examination of the lens should be included as appropriate in the medical monitoring of people occupationally exposed to radiation, if there is potentially high lens exposure, adoption of research strategies to develop a basic understanding of the mechanisms underlying radiation induced cataracts. The International Commission on Radiological Protection (ICRP) actually assumes a threshold dose of 0.5 Gy and, based on this assumption, has recommended in 2011 to reduce the dose limit for the eye lens from 150 mSv in a year to 20 mSv in a year for people occupationally exposed to ionising radiation. (orig.)

  8. Visual Outcome of Traumatic Cataract at a Tertiary Eye Care Centre in North India: A Prospective Study

    Science.gov (United States)

    Sharma, Ashish Kumar; Srivastava, Jai Prakash; Iqbal, Jawed

    2016-01-01

    Introduction One of the most common presentations of blunt and penetrating ocular trauma is traumatic cataract. It remains a significant cause of visual impairment and physical disability among adults and children. It is associated with various ocular injuries. Aim To evaluate the associated ocular injuries and final outcome of patients with traumatic cataract along with their demographic features and modes of trauma. Materials and Methods A prospective study done in Department of Ophthalmology in M.L.B. Medical college, Jhansi from February 2010 to July 2011. A total of 48 patients diagnosed as a case of traumatic cataract were subjected to a detailed history, systemic and local examination with relevant investigations. Medical or surgical managements were done accordingly. Patients were subsequently followed-up and visual acuity was recorded. Appropriate statistical tests were applied. Results A 54.2% patients sustained penetrating trauma while 45.8% got blunt injury. Out of total, 79% patients were males while 50% were less than 15 years of age. Causative agents were stone, wood items, stick, metal objects etc. Among blunt trauma cases, 64% of the patients had visual acuity 6/18. Anterior segment was more involved as compared to posterior segment. A 38.5% patients had corneal opacity among penetrating injury patients. The interval between trauma and surgery was less than one month among 75% of patients. After three months of surgery, 43.7% patients had visual acuity of >6/18. Conclusion This study provides recent data of patients hospitalized after ocular trauma and diagnosed as a case of traumatic cataract. Traumatic cataract occurs mostly in younger males. Surgical intervention is necessary to improve visual outcome. Good visual outcome was obtained in nearly half of the patients. Traumatic cataract patients can have good visual outcome depending upon proper management. PMID:26894101

  9. Coaxial Microincision Cataract Surgery versus Standard Coaxial Small-Incision Cataract Surgery: A Meta-Analysis of Randomized Controlled Trials

    Science.gov (United States)

    Shentu, Xingchao; Zhang, Xin; Tang, Xiajing; Yu, Xiaoning

    2016-01-01

    Background We conducted this meta-analysis to compare the outcomes of coaxial microincision cataract surgery (C-MICS) and standard coaxial small incision cataract surgery (C-SICS). Methods The outcomes of randomized controlled trials (RCTs) reporting C-MICS and C-SICS were collected from PubMed, Web of Science, and The Cochrane Library in May 2015. The final meta-analysis was conducted on the following intraoperative and postoperative outcomes: ultrasound time (UST), effective phacoemulsification time (EPT), balanced salt solution use (BSS use), cumulative dissipated energy (CDE), mean surgery time, endothelial cell loss percentage (ECL%), best corrected visual acuity (BCVA), increased central corneal thickness (CCT), laser flare photometry values and surgically induced astigmatism (SIA). Results A total of 15 RCTs, involving 1136 eyes, were included in the final meta-analysis. No significant between-group differences were detected in EPT, BSS use, CDE, BCVA, laser flare photometry values or increased CCT. However, the C-MICS group showed less SIA (at postoperative day 7: p<0.01; at postoperative day 30 or more: p<0.01) and greater ECL% (at postoperative day 60 or more: p<0.01), whereas the C-SICS group required a shorter UST (p<0.01). Conclusions The present meta-analysis suggested that the C-MICS technique was more advantageous than C-SICS in terms of SIA, but C-MICS required a longer UST and induced a higher ECL%. Further studies should be done to confirm our results. PMID:26745279

  10. Coaxial Microincision Cataract Surgery versus Standard Coaxial Small-Incision Cataract Surgery: A Meta-Analysis of Randomized Controlled Trials.

    Directory of Open Access Journals (Sweden)

    Xingchao Shentu

    Full Text Available We conducted this meta-analysis to compare the outcomes of coaxial microincision cataract surgery (C-MICS and standard coaxial small incision cataract surgery (C-SICS.The outcomes of randomized controlled trials (RCTs reporting C-MICS and C-SICS were collected from PubMed, Web of Science, and The Cochrane Library in May 2015. The final meta-analysis was conducted on the following intraoperative and postoperative outcomes: ultrasound time (UST, effective phacoemulsification time (EPT, balanced salt solution use (BSS use, cumulative dissipated energy (CDE, mean surgery time, endothelial cell loss percentage (ECL%, best corrected visual acuity (BCVA, increased central corneal thickness (CCT, laser flare photometry values and surgically induced astigmatism (SIA.A total of 15 RCTs, involving 1136 eyes, were included in the final meta-analysis. No significant between-group differences were detected in EPT, BSS use, CDE, BCVA, laser flare photometry values or increased CCT. However, the C-MICS group showed less SIA (at postoperative day 7: p<0.01; at postoperative day 30 or more: p<0.01 and greater ECL% (at postoperative day 60 or more: p<0.01, whereas the C-SICS group required a shorter UST (p<0.01.The present meta-analysis suggested that the C-MICS technique was more advantageous than C-SICS in terms of SIA, but C-MICS required a longer UST and induced a higher ECL%. Further studies should be done to confirm our results.

  11. Internal wave structures in abyssal cataract flows

    Science.gov (United States)

    Makarenko, Nikolay; Liapidevskii, Valery; Morozov, Eugene; Tarakanov, Roman

    2014-05-01

    We discuss some theoretical approaches, experimental results and field data concerning wave phenomena in ocean near-bottom stratified flows. Such strong flows of cold water form everywhere in the Atlantic abyssal channels, and these currents play significant role in the global water exchange. Most interesting wave structures arise in a powerful cataract flows near orographic obstacles which disturb gravity currents by forced lee waves, attached hydraulic jumps, mixing layers etc. All these effects were observed by the authors in the Romanche and Chain fracture zones of Atlantic Ocean during recent cruises of the R/V Akademik Ioffe and R/V Akademik Sergei Vavilov (Morozov et al., Dokl. Earth Sci., 2012, 446(2)). In a general way, deep-water cataract flows down the slope are similar to the stratified flows examined in laboratory experiments. Strong mixing in the sill region leads to the splitting of the gravity current into the layers having the fluids with different densities. Another peculiarity is the presence of critical layers in shear flows sustained over the sill. In the case under consideration, this critical level separates the flow of near-bottom cold water from opposite overflow. In accordance with known theoretical models and laboratory measurements, the critical layer can absorb and reflect internal waves generated by the topography, so the upward propagation of these perturbations is blocked from above. High velocity gradients were registered downstream in the vicinity of cataract and it indicates the existence of developed wave structures beyond the sill formed by intense internal waves. This work was supported by RFBR (grants No 12-01-00671-a, 12-08-10001-k and 13-08-10001-k).

  12. Cataract and progressing keratoconus — solution?

    Directory of Open Access Journals (Sweden)

    K. B. Pershin

    2015-10-01

    Full Text Available Purpose: To develop an uniform method of the treatment for patients with progressive keratoconus (stage 1‑2 and cataract. Patients and methods: 4 patients (5 eyes with cataract and progressive keratoconus stage 1‑2 were enrolled in the study. Mean age was 42 years. In all patients, standard ophthalmic examination as well corneal topography, anterior segment optical coherence tomography, biometry, and IOL power calculations using IOLMaster were performed. Mean uncorrected visual acuity (UCVA was 0.1 while mean best-corrected visual acuity (BCVA was 0.4. Surgical technique included two steps. The first step was the creation of corneal tunnels with femtosecond laser with subsequent phaco and monofocal aspheric IOL implantation. The second step (1‑2 weeks later was the implantation of intrastromal ring segments based on corneal topography and corneal crosslinking.Results: After the first step, all patients had myopic refraction (from –1.0 D to –2.5 D. Cylindrical component was almost unchanged. After the second step, the patients reported the vision improvement, mainly due to UCVA. Both spherical (myopic and cylindrical components decreased, mainly due to the steep meridian. After the treatment, optical power of the cornea decreased, mainly due to the steep meridian. UCVA was 0.6 or more in 60 % of cases, final BCVA was 0.8‑1.0 in 80 % of cases. Neither intraoperative nor postoperative (follow-up was 2 years complications were observed.Conclusions: Combined phaco and prior creation of corneal tunnels with subsequent intrastromal ring segment implantation and crosslinking in patients with cataract and progressive keratoconus stage 1‑2 is safe, provides good predictable outcome and significantly reduces rehabilitation period.

  13. VISUAL OUTCOME FOLLOWING SURGERY OF TRAUMATIC CATARACT

    Directory of Open Access Journals (Sweden)

    Prasad Rao

    2015-04-01

    Full Text Available AIM: To assess the visual outcome following traumatic cataract surgery and to assess the predictors of better visual outcome STUDY SETUP AND DESIGN: This is a prospective case study made on consecutive series of patients with traumatic cataract who underwent surgery between November 2012 to July 2013 at Government Regional eye hospital, Andhra medical college, Visakhapatnam . METHODS: Study was made on 100 eyes of 100 patients. Patient’s detailed history, clinical features, pre - operative examination, surgical intervention, post - operative visual acuity and follow up refraction changes record. RESULTS: In total , 100 eyes of 100 patients were included . Out of 100 cases, 78 cases (78% were males and 22 cases (22% were females. Good visual acuity of 6/6 – 6/18 was achieved by 70 cases, (70% out of which 58 cases (58% are closed globe type and 12 cases ( 12% are open globe type. 4 cases ( 4% achieved visual acuity of 6/24 to 6/609 . ( 1 26 cases ( 26% achieved a poor visual outcome of < 6/60 out of which 22 cases (22% are open globe type and 4 cases 4% are closed globe type . ( 2 CONCLUSIONS: Closed globe injury has a favorable prognosis for a satisfactory better that 6/18 visual recovery after surgical management of traumatic cataract , compared to open globe type. In case of open globe injury . (3 prompt wound repair , proper use of drugs to reduce infection , inflammation followed by timely surgery may improve the visual prognosis if there is no other sight threatening injury.

  14. Mechanisms of post-transcriptional regulation of genes involved in FTDP-17

    OpenAIRE

    Fontana, Francesca

    2015-01-01

    MicroRNAs (miRNAs) are small non coding RNAs of 18-25 nt, capable of regulating mRNA translation and gene expression at post-transcriptional level. Alteration of miRNAs expression is often associated with human diseases, such as cancers and neurodegenerative pathologies. The main objective of this study is an analysis of the post-transcriptional regulation played by miRNAs of two important genes, MAPT and GRN, involved in Frontotemporal Dementia with Parkinsonism linked to chromosome 17 (FTDP...

  15. Understanding the molecular mechanisms involved in the interfacial self-healing of supramolecular rubbers

    OpenAIRE

    Bose, R.K.; Garcia Espallargas, S.J.; Zwaag, S. van der

    2013-01-01

    Supramolecular rubbers based on 2-aminoethylimidazolidone and fatty acids with epoxy crosslinks have been shown to self-heal via multiple hydrogen bonding sites. In this work, several tools are used to investigate the molecular mechanisms taking place at the interface to understand cohesive healing in these polymers. The quantification of self-healing was performed via a tapered double cantilever beam (TDCB) geometry. The TDCB geometry is especially amenable to studying multiple healing cycle...

  16. Mechanisms of Action Involved in Ozone Therapy: Is healing induced via a mild oxidative stress?

    OpenAIRE

    Sagai Masaru; Bocci Velio

    2011-01-01

    Abstract The potential mechanisms of action of ozone therapy are reviewed in this paper. The therapeutic efficacy of ozone therapy may be partly due the controlled and moderate oxidative stress produced by the reactions of ozone with several biological components. The line between effectiveness and toxicity of ozone may be dependent on the strength of the oxidative stress. As with exercise, it is well known that moderate exercise is good for health, whereas excessive exercise is not. Severe o...

  17. Optimization of the Asymptotic Property of Mutual Learning Involving an Integration Mechanism of Ensemble Learning

    OpenAIRE

    Hara, Kazuyuki; Yamada, Takahiro

    2007-01-01

    We propose an optimization method of mutual learning which converges into the identical state of optimum ensemble learning within the framework of on-line learning, and have analyzed its asymptotic property through the statistical mechanics method.The proposed model consists of two learning steps: two students independently learn from a teacher, and then the students learn from each other through the mutual learning. In mutual learning, students learn from each other and the generalization er...

  18. Recovery of Respiratory Activity after C2 hemisection (C2HS): Involvement of Adenosinergic Mechanisms

    OpenAIRE

    Nantwi, Kwaku D

    2009-01-01

    Consequences of spinal cord injury (SCI) depend on the level and extent of injury. Cervical SCI often results in a compromised respiratory system. Primary treatment of SCI patients with respiratory insufficiency continues to be with mechanical ventilatory support. In an animal model of SCI, an upper cervical spinal cord hemisection paralyzes the hemidiaphragm ipsilateral to the side of injury. However, a latent respiratory motor pathway can be activated to restore respiratory function after i...

  19. Physiological and Molecular Mechanism of Nitric Oxide (NO) Involved in Bermudagrass Response to Cold Stress

    OpenAIRE

    Fan, Jibiao; Chen, Ke; Amombo, Erick; Hu, Zhengrong; Chen, Liang; Fu, Jinmin

    2015-01-01

    Bermudagrass is widely utilized in parks, lawns, and golf courses. However, cold is a key factor limiting resource use in bermudagrass. Therefore, it is meaningful to study the mechanism of bermudagrass response to cold. Nitric oxide (NO) is a crucial signal molecule with multiple biological functions. Thus, the objective of this study was to investigate whether NO play roles in bermudagrass response to cold. Sodium nitroprusside (SNP) was used as NO donor, while 2-phenyl-4,4,5,5-tetramentyli...

  20. Vascular oxidative stress upregulates angiotensin II type I receptors via mechanisms involving nuclear factor kappa B

    OpenAIRE

    Bhatt, Siddhartha R.; Lokhandwala, Mustafa F.; Banday, Anees Ahmad

    2014-01-01

    The association of oxidative stress with hypertension is well known. However, a causal role of oxidative stress in hypertension is unclear. Vascular angiotensin II type 1 receptor (AT1R) upregulation is a prominent contributor to pathogenesis of hypertension. However, the mechanisms causing this upregulation are unknown. Oxidative stress is an important regulator of protein expression via activation of transcription factors such as nuclear factor kappa B (NFκB). The present study was carried ...

  1. Pathogenic Mechanism of an Autism-Associated Neuroligin Mutation Involves Altered AMPA-Receptor Trafficking

    OpenAIRE

    Chanda, Soham; Aoto, Jason; Lee, Sung-Jin; Wernig, Marius; Südhof, Thomas C.

    2015-01-01

    Neuroligins are postsynaptic cell-adhesion molecules that bind to presynaptic neurexins. Although the general synaptic role of neuroligins is undisputed, their specific functions at a synapse remain unclear, even controversial. Moreover, many neuroligin gene mutations were associated with autism, but the pathophysiological relevance of these mutations is often unknown, and their mechanisms of action uninvestigated. Here, we examine the synaptic effects of an autism-associated neuroligin-4 sub...

  2. Molecular mechanisms involved in the bidirectional relationship between diabetes mellitus and periodontal disease

    Directory of Open Access Journals (Sweden)

    Harpreet Singh Grover

    2013-01-01

    Full Text Available Both diabetes and periodontitis are chronic diseases. Diabetes has many adverse effects on the periodontium, and conversely periodontitis may have deleterious effects further aggravating the condition in diabetics. The potential common pathophysiologic pathways include those associated with inflammation, altered host responses, altered tissue homeostasis, and insulin resistance. This review examines the relationship that exists between periodontal diseases and diabetes mellitus with a focus on potential common pathophysiologic mechanisms.

  3. The association between refractive errors and cataract: The Tehran eye study

    Directory of Open Access Journals (Sweden)

    Hassan Hashemi

    2011-01-01

    Conclusion : Individuals with nuclear and PSC showed a significantly higher prevalence of myopia while the prevalence of hyperopia was lower in those with cataract. High myopia was seen in higher grades of nuclear cataract. The high percentage of hyperopia was also significant in patients with cortical cataract. More studies are necessary to clarify the correlation between cortical cataract and hyperopia.

  4. Copper levels in human mixed, nuclear brunescence, and posterior subcapsular cataract.

    OpenAIRE

    Balaji, M.; K. Sasikala; Ravindran, T

    1992-01-01

    The study was undertaken to determine the copper content in different human cataractous lenses. The level of copper increased with increasing age in nuclear brunescence and mixed cataractous lens and a low amount of copper was observed in the posterior subcapsular cataractous lens with increasing age. Cataractous lenses of females have greater amounts of copper compared with males.

  5. Comparison of Delayed-Onset Glaucoma and Early-Onset Glaucoma after Infantile Cataract Surgery

    OpenAIRE

    Kang, Kui Dong; Yim, Hye Bin; Biglan, Albert W.

    2006-01-01

    Purpose To investigate the causes and characteristics of glaucoma in children following cataract surgery. Methods Twenty-four patients (37 eyes) with uncomplicated congenital cataracts who developed glaucoma after cataract surgery were studied retrospectively. Variables included cataract morphology, surgical techniques, post-operative complications, time to the onset of glaucoma, gonioscopic findings, presence of microcornea and the histopathologic characteristics of the filtration angle (in ...

  6. Phenanthrene causes ocular developmental toxicity in zebrafish embryos and the possible mechanisms involved

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Lixing [State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Xiamen University, Xiamen 361005 (China); Wang, Chonggang [State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Xiamen University, Xiamen 361005 (China); State Key Laboratory of Marine Environmental Science, Xiamen University, Xiamen (China); Zhang, Youyu; Wu, Meifang [State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Xiamen University, Xiamen 361005 (China); Zuo, Zhenghong, E-mail: zuozhenghong@xmu.edu.cn [State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Xiamen University, Xiamen 361005 (China); State Key Laboratory of Marine Environmental Science, Xiamen University, Xiamen (China)

    2013-10-15

    Highlights: • Phe exposure caused obvious morphological changes in the retina. • Phe exposure caused apoptosis and reduction of cell proliferation in the retina. • Phe causes ocular toxicity might be via the AhR/Zeb1/Mitf/Pax6 signaling pathway. • AhR is a repressor of Zeb1. -- Abstract: Recent studies show that polycyclic aromatic hydrocarbons (PAHs) may be a candidate cause of developmental defects of the retina, but the mechanism is still unclear. We evaluated the mechanism(s) underlying PAH-induced retinal development defects due to exposure to environmental concentrations of Phenanthrene (Phe) in zebrafish. We found that exposure to environmental concentrations of Phe caused obvious morphological changes, developmental retardation, apoptosis, and reduction of cell proliferation in the retina. Our results indicated that Phe could cause visual system developmental defects. Phe exposure up-regulated aryl hydrocarbon receptor (AhR) and microphthalmia-associated transcription factor (Mtif) expression, and down-regulated zinc finger E-box binding homeobox 1 (Zeb1) and paired box 6 (Pax6). Moreover, we demonstrated that AhR was a repressor of Zeb1. We propose that Phe's ocular toxicity is mediated by up-regulating AhR, which then down-regulates Zeb1, in turn inducing Mitf expression while inhibiting Pax6 expression.

  7. Femtosecond laser in refractive and cataract surgeries

    Institute of Scientific and Technical Information of China (English)

    Han-Han; Liu; Ying; Hu; Hong-Ping; Cui

    2015-01-01

    In the past few years, 9 unique laser platforms have been brought to the market. As femtosecond(FS) laserassisted ophthalmic surgery potentially improves patient safety and visual outcomes, this new technology indeed provides ophthalmologists a reliable new option. But this new technology also poses a range of new clinical and financial challenges for surgeons. We provide an overview of the evolution of FS laser technology for use in refractive and cataract surgeries. This review describes the available laser platforms and mainly focuses on discussing the development of ophthalmic surgery technologies.

  8. Mechanism(s) Involved in Carbon Monoxide-releasing Molecule-2-mediated Cardioprotection During Ischaemia-reperfusion Injury in Isolated Rat Heart

    OpenAIRE

    Soni, H. M.; Jain, M. R.; Anita A. Mehta

    2012-01-01

    The purpose of the present study was to determine the mechanism(s) involved in carbon monoxide-releasing molecule-2, carbon monoxide-releasing molecule-2-induced cardioprotection. We used the transition metal carbonyl compound carbon monoxide-releasing molecule-2 that can act as carbon monoxide donor in cardiac ischaemia-reperfusion injury model using isolated rat heart preparation. Langendorff′s perfused rat hearts when treated with carbon monoxide-releasing molecule-2 (50 μM) for 10 min bef...

  9. Uncertainties in neutrinoless $\\beta \\beta $ decay transition matrix elements within mechanisms involving light Majorana neutrinos, classical Majorons and sterile neutrinos

    CERN Document Server

    Rath, P K; Chaturvedi, K; Lohani, P; Raina, P K; Hirsch, J G

    2013-01-01

    In the PHFB model, uncertainties in the nuclear transition matrix elements for the neutrinoless double-$\\beta $ decay of $\\ ^{94,96}$Zr, $^{98,100}$Mo, $^{104}$Ru, $^{110}$Pd, $^{128,130}$Te and $^{150}$Nd isotopes within mechanisms involving light Majorana neutrinos, classical Majorons and sterile neutrinos are statistically estimated by considering sets of sixteen (twenty-four) matrix elements calculated with four different parametrization of the pairing plus multipolar type of effective two-body interaction, two sets of form factors and two (three) different parameterizations of Jastrow type of short range correlations. In the mechanisms involving the light Majorana neutrinos and classical Majorons, the maximum uncertainty is about 15% and in the scenario of sterile neutrinos, it varies in between approximately 4 (9)%--20 (36)% without(with) Jastrow short range correlations with Miller-Spencer parametrization, depending on the considered mass of the sterile neutrinos.

  10. Down-regulation of mechanisms involved in cell transport and maintenance of mucosal integrity in pigs infected with Lawsonia intracellularis

    OpenAIRE

    Smith, Sionagh H; Wilson, Alison D.; Van Ettinger, Imke; MacIntyre, Neil; Archibald, Alan L.; Ait-Ali, Tahar

    2014-01-01

    International audience Lawsonia intracellularis is an obligate intracellular bacterium, responsible for the disease complex known as proliferative enteropathy (PE). L. intracellularis is associated with intestinal crypt epithelial cell proliferation but the mechanisms responsible are yet to be defined. Microarray analysis was used to investigate the host-pathogen interaction in experimentally infected pigs to identify pathways that may be involved. Ileal samples originating from twenty-eig...

  11. Key stages of mammary gland development: Molecular mechanisms involved in the formation of the embryonic mammary gland

    OpenAIRE

    Hens, Julie R; Wysolmerski, John J

    2005-01-01

    The development of the embryonic mammary gland involves communication between the epidermis and mesenchyme and is coordinated temporally and spatially by various signaling pathways. Although many more genes are likely to control mammary gland development, functional roles have been identified for Wnt, fibroblast growth factor, and parathyroid hormone-related protein signaling. This review describes what is known about the molecular mechanisms that regulate embryonic mammary gland development.

  12. Involvement of three mechanisms in the alteration of cytokine responses by sodium methyldithiocarbamate

    International Nuclear Information System (INIS)

    Sodium methyldithiocarbamate (SMD) is the third most abundantly used conventional pesticide in the U.S. We recently reported that it alters the induction of cytokine production mediated though Toll-like receptor (TLR) 4 at relevant dosages in mice. Its chemical properties and evidence from the literature suggest thee potential mechanisms of action for this compound. It could either act as a free radical scavenger (by means of its free S-group) or promote oxidation by breaking down to form methylisothiocyanate, which can deplete glutathione. It is a potent copper chelator and may affect the availability of copper to a number of copper-dependent enzymes (including some signaling molecules). SMD induces a classical neuroendocrine stress response characterized by elevated serum corticosterone concentrations, which could affect cytokine production. Although each of these mechanisms could potentially contribute to altered cytokine responses, direct evidence is lacking. The present study was conducted to obtain such evidence. The role of redox balance was investigated by pretreating mice with N-acetyl cysteine (NAC), which increases cellular glutathione concentrations, before administration of SMD. NAC exacerbated the SMD-induced suppression of IL-12 and the SMD-induced enhancement of IL-10 in the serum. The role of copper chelation was investigated by comparing the effects of SMD with an equimolar dose to SMD that was administered in the form of a copper chelation complex. Addition of copper significantly decreased the action of SMD on IL-12 production but not on IL-10 production. The role of the stress response was investigated by pretreating mice with antagonists of corticosterone and catecholamines. This treatment partially prevented the action of SMD on IL-10 and IL-12 in the peritoneal fluid. The results suggest that all of the proposed mechanisms have some role in the alteration of cytokine production by SMD

  13. Neural mechanisms involved in the detection of our first name : A combined ERPs and PET study

    OpenAIRE

    Perrin, Fabien; Maquet, Pierre; Peigneux, Philippe; Ruby, P.; Degueldre, Christian; Balteau, Evelyne; Del Fiore, Guy; Moonen, Gustave; Luxen, André; Laureys, Steven

    2005-01-01

    In everyday social interactions, hearing our own first name captures our attention and gives rise to a sense of self-awareness, since it is one of the most socially self related stimulus. In the present study, we combined ERPs and PET scan methods to explore the cerebral mechanisms underlying the detection of our own name. While categorical analyses of PET data failed to reveal significant results, we found that the amplitude of the P3 component, elicited when hearing one's own name, correlat...

  14. GR-127935-sensitive mechanism mediating hypotension in anesthetized rats: are 5-HT5B receptors involved?

    Science.gov (United States)

    Sánchez-Maldonado, Carolina; López-Sánchez, Pedro; Anguiano-Robledo, Liliana; Leopoldo, Marcello; Lacivita, Enza; Terrón, José A

    2015-04-01

    The 5-HT1B/1D receptor antagonist, GR-127935, inhibits hypotensive responses produced by the 5-HT1A, 5-HT1B/1D and 5-HT7 receptor agonist, and 5-HT5A/5B receptor ligand, 5-carboxamidotryptamine (5-CT), in rats. This work further characterized the above mechanism using more selective 5-HT1B and 5-HT1D receptor antagonists. Also, expression of 5-HT5A and 5-HT5B receptor mRNAs in blood vessels was searched by reverse transcription polymerase chain reaction. Decreases in diastolic blood pressure induced by 5-CT (0.001-10 μg/kg, intravenously) were analyzed in anesthetized rats that had received intravenous vehicle (1 mL/kg), SB-224289 (5-HT1B antagonist; 0.3 and 1.0 mg/kg), BRL15572 (5-HT1D antagonist; 0.3 and 1.0 mg/kg), SB-224289 + BRL15572 (0.3 mg/kg, each), or SB-224289 + BRL15572 (0.3 mg/kg, each) + GR-127935 (1 mg/kg). Because only the latter treatment inhibited 5-CT-induced hypotension, suggestive of a mechanism unrelated to 5-HT1B/1D receptors, the effects of antagonists/ligands at 5-HT5A (SB-699551, 1 mg/kg), 5-HT6 (SB-399885, 1 mg/kg), and 5-HT1B/1D/5A/5B/7 receptors (ergotamine, 0.1 mg/kg) on 5-CT-induced hypotension were tested. Interestingly, only ergotamine blocked 5-CT-induced responses; this effect closely paralleled that of SB-224289 + BRL-15572 + GR-127935. Neither did ergotamine nor GR-127935 inhibit hypotensive responses induced by the 5-HT7 receptor agonist, LP-44. Faint but clear bands corresponding to 5-HT5A and 5-HT5B receptor mRNAs in aorta and mesenteric arteries were detected. Results suggest that the GR-127935-sensitive mechanism mediating hypotension in rats is unrelated to 5-HT1B, 5-HT1D, 5-HT5A, 5-HT6, and 5-HT7 receptors. This mechanism, however, resembles putative 5-HT5B receptors. PMID:25502305

  15. Mechanisms involved in the swelling of erythrocytes caused by Pacific and Caribbean ciguatoxins

    OpenAIRE

    Sauviat, M. P.; Boydron Le Garrec, Raphaëlle; Masson, J.B.; Lewis, R.L.; Vernoux, J. P.; Molgo, J; Laurent, Dominique; Benoit, E.

    2006-01-01

    The mechanisms underlying the swelling of frog red blood cells (RBC), induced by Pacific (P-CTX-1) and Caribbean (C-CTX-1) ciguatoxins (CTXs), were investigated by measuring the length, width and surface of their elliptic shape. P-CTX-1 (0.5 to 5 nM) and C-CTX-1 (1 mu M) induced RBC swelling within 60 min. The CTXs-induced RBC swelling was blocked by apamin (1 mu M) and by Sr2+ (1 mu M). P-CTX-1-induced RBC swelling was prevented and inhibited by H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one(27 ...

  16. A novel mechanism involved in the coupling of mitochondrial biogenesis to oxidative phosphorylation

    Directory of Open Access Journals (Sweden)

    Jelena Ostojić

    2014-01-01

    Full Text Available Mitochondria are essential organelles that are central to a multitude of cellular processes, including oxidative phosphorylation (OXPHOS, which produces most of the ATP in animal cells. Thus it is important to understand not only the mechanisms and biogenesis of this energy production machinery but also how it is regulated in both physiological and pathological contexts. A recent study by Ostojić et al. [Cell Metabolism (2013 18, 567-577] has uncovered a regulatory loop by which the biogenesis of a major enzyme of the OXPHOS pathway, the respiratory complex III, is coupled to the energy producing activity of the mitochondria.

  17. Some mechanisms involved in the radiosensitization of E.coli B/r by paracetamol

    International Nuclear Information System (INIS)

    Paracetamol, a widely-used analgesic and antipyretic drug, sensitized E.coli B/r to 60Co gamma-rays under hypoxic conditions. Part of the sensitizing effect has been shown to be due to an electron adduct of the drug. Paracetamol inhibited both post-irradiation DNA and protein syntheses. The targets involved in the inhibition of post-irradiation DNA synthesis have been shown to be different in the presence of the sensitizer. Increased DNA degradation after irradiation was also observed when E.coli B/r were irradiated in the presence of the drug. The presence of paracetamol during hypoxic irradiation of E.coli B/r resulted in the enhancement of DNA single-strand scissions with no apparent effect on their rejoining. (author)

  18. Sensitizing Children to the Social and Emotional Mechanisms involved in Racism: a program evaluation

    Directory of Open Access Journals (Sweden)

    Sofia Triliva

    2014-11-01

    Full Text Available This paper describes and discusses the results of an intervention aiming to sensitize children to the social and emotional processes involved in racism. The intervention was applied and evaluated in 10 Greek elementary schools. The goals and the intervention methods of the program modules are briefly outlined and the results of the program evaluation are elaborated and discussed. Two-hundred students participated in the program and 180 took part in the pre-and-post-testing which assessed their ability to identify emotions associated with prejudice, discrimination and stereotypical thinking; to understand similarities and differences between people; and to develop perspective taking and empathic skills in relation to diverse others. Results indicate gains in all three areas of assessment although the increased ability to identify similarities between people can also be attributed to age/grade effects. The implications of the findings are discussed with regard to antiracism intervention methods and evaluation strategies.

  19. Signaling mechanisms involved in the acute effects of estradiol on 5-HT clearance.

    Science.gov (United States)

    Benmansour, Saloua; Privratsky, Anthony A; Adeniji, Opeyemi S; Frazer, Alan

    2014-05-01

    Estradiol was found previously to have an antidepressant-like effect and to block the ability of selective serotonin reuptake inhibitors (SSRIs) to have an antidepressant-like effect. The antidepressant-like effect of estradiol was due to estrogen receptor β (ERβ) and/or GPR30 activation, whereas estradiol's blockade of the effect of an SSRI was mediated by ERα. This study focuses on investigating signaling pathways as well as interacting receptors associated with these two effects of estradiol. In vivo chronoamperometry was used to measure serotonin transporter (SERT) function. The effect of local application of estradiol or selective agonists for ERα (PPT) or ERβ (DPN) into the CA3 region of the hippocampus of ovariectomized (OVX) rats on 5-hydroxytryptamine (5-HT) clearance as well as on the ability of fluvoxamine to slow 5-HT clearance was examined after selective blockade of signaling pathways or that of interacting receptors. Estradiol- or DPN-induced slowing of 5-HT clearance mediated by ERβ was blocked after inhibition of MAPK/ERK1/2 but not of PI3K/Akt signaling pathways. This effect also involved interactions with TrkB, and IGF-1 receptors. Estradiol's or PPT's inhibition of the fluvoxamine-induced slowing of 5-HT clearance mediated by ERα, was blocked after inhibition of either MAPK/ERK1/2 or PI3K/Akt signaling pathways. This effect involved interactions with the IGF-1 receptor and with the metabotropic glutamate receptor 1, but not with TrkB. This study illustrates some of the signaling pathways required for the effects of estradiol on SERT function, and particularly shows that ER subtypes elicit different as well as common signaling pathways for their actions. PMID:24423185

  20. A possible new mechanism involved in non-uniform field breakdown in gaseous dielectrics

    International Nuclear Information System (INIS)

    The electrical breakdown of gases under uniform field conditions is fairly well understood in terms of the Townsend's breakdown theory. In most cases involving uniform fields, the breakdown voltage can be estimated via this theory using basic electron impact parameters for molecules in their ground electronic states. In contrast, a consistent model of gaseous breakdown under nonuniform fields is not available at present although substantial progress has been made recently. We point out the possibility that electron impact processes involving high-lying electronically-excited states may play a significant role under non-uniform field conditions. Thus, such processes may need to be included in order to obtain a better understanding of non-uniform field breakdown phenomena. The general, breakdown characteristics of highly non-uniform field gaps can be illustrated by that for a point-plane geometry. It has been found that the breakdown voltage for such a gap can be calculated by a simple streamer criterion if the pressure P, is above a critical value, Pc; for P c, the estimated breakdown voltage is found to coincide with the corona inception voltage, with the actual breakdown occurring at a higher voltage, corona discharges occur only for P c. In other words, the presence of corona in the pressure region below Pc seems to prevent the breakdown from occurring at the predicted value. This has led to the term ''corona stabilization'' to describe the enhancement in the breakdown voltage for pressures below Pc. Non-uniform field breakdown measurements in gases will be discussed. We will discuss the possibility that the ''corona stabilization'' is due to the prevention of avalanche progression by attachment of free electrons to molecules in their high-lying electronically-excited states. Information on electron attachment to electronically-excited states of molecules was not available up until the late 1980's

  1. A possible new mechanism involved in non-uniform field breakdown in gaseous dielectrics

    Energy Technology Data Exchange (ETDEWEB)

    Pinnaduwage, L.A.; Christophorou, L.G.

    1994-06-01

    The electrical breakdown of gases under uniform field conditions is fairly well understood in terms of the Townsend`s breakdown theory. In most cases involving uniform fields, the breakdown voltage can be estimated via this theory using basic electron impact parameters for molecules in their ground electronic states. In contrast, a consistent model of gaseous breakdown under nonuniform fields is not available at present although substantial progress has been made recently. We point out the possibility that electron impact processes involving high-lying electronically-excited states may play a significant role under non-uniform field conditions. Thus, such processes may need to be included in order to obtain a better understanding of non-uniform field breakdown phenomena. The general, breakdown characteristics of highly non-uniform field gaps can be illustrated by that for a point-plane geometry. It has been found that the breakdown voltage for such a gap can be calculated by a simple streamer criterion if the pressure P, is above a critical value, P{sub c}; for P < P{sub c}, the estimated breakdown voltage is found to coincide with the corona inception voltage, with the actual breakdown occurring at a higher voltage, corona discharges occur only for P < P{sub c}. In other words, the presence of corona in the pressure region below P{sub c} seems to prevent the breakdown from occurring at the predicted value. This has led to the term ``corona stabilization`` to describe the enhancement in the breakdown voltage for pressures below P{sub c}. Non-uniform field breakdown measurements in gases will be discussed. We will discuss the possibility that the ``corona stabilization`` is due to the prevention of avalanche progression by attachment of free electrons to molecules in their high-lying electronically-excited states. Information on electron attachment to electronically-excited states of molecules was not available up until the late 1980`s.

  2. A cell-regulatory mechanism involving feedback between contraction and tissue formation guides wound healing progression.

    Directory of Open Access Journals (Sweden)

    Clara Valero

    Full Text Available Wound healing is a process driven by cells. The ability of cells to sense mechanical stimuli from the extracellular matrix that surrounds them is used to regulate the forces that cells exert on the tissue. Stresses exerted by cells play a central role in wound contraction and have been broadly modelled. Traditionally, these stresses are assumed to be dependent on variables such as the extracellular matrix and cell or collagen densities. However, we postulate that cells are able to regulate the healing process through a mechanosensing mechanism regulated by the contraction that they exert. We propose that cells adjust the contraction level to determine the tissue functions regulating all main activities, such as proliferation, differentiation and matrix production. Hence, a closed-regulatory feedback loop is proposed between contraction and tissue formation. The model consists of a system of partial differential equations that simulates the evolution of fibroblasts, myofibroblasts, collagen and a generic growth factor, as well as the deformation of the extracellular matrix. This model is able to predict the wound healing outcome without requiring the addition of phenomenological laws to describe the time-dependent contraction evolution. We have reproduced two in vivo experiments to evaluate the predictive capacity of the model, and we conclude that there is feedback between the level of cell contraction and the tissue regenerated in the wound.

  3. Cellular and molecular mechanisms involved in the neurotoxicity of opioid and psychostimulant drugs.

    Science.gov (United States)

    Cunha-Oliveira, Teresa; Rego, Ana Cristina; Oliveira, Catarina R

    2008-06-01

    Substance abuse and addiction are the most costly of all the neuropsychiatric disorders. In the last decades, much progress has been achieved in understanding the effects of the drugs of abuse in the brain. However, efficient treatments that prevent relapse have not been developed. Drug addiction is now considered a brain disease, because the abuse of drugs affects several brain functions. Neurological impairments observed in drug addicts may reflect drug-induced neuronal dysfunction and neurotoxicity. The drugs of abuse directly or indirectly affect neurotransmitter systems, particularly dopaminergic and glutamatergic neurons. This review explores the literature reporting cellular and molecular alterations reflecting the cytotoxicity induced by amphetamines, cocaine and opiates in neuronal systems. The neurotoxic effects of drugs of abuse are often associated with oxidative stress, mitochondrial dysfunction, apoptosis and inhibition of neurogenesis, among other mechanisms. Understanding the mechanisms that underlie brain dysfunction observed in drug-addicted individuals may contribute to improve the treatment of drug addiction, which may have social and economic consequences. PMID:18440072

  4. Mechanical Properties Involved in the Micro-forming of Ultra-thin Stainless Steel Sheets

    Science.gov (United States)

    Pham, Cong-Hanh; Thuillier, Sandrine; Manach, Pierre-Yves

    2015-08-01

    The objective of this paper is to characterize the mechanical behavior of an ultra-thin stainless steel, of 0.15-mm thickness, that is commonly used in the manufacturing of miniature connectors. The main focus is the relationship between some microstructural features, like grain size and surface roughness, and the macroscopic mechanical behavior investigated in uniaxial tension and simple shear. In tension, adaptations to the very small sheet thickness, in order to hold the specimen under the grips, are presented. Yield stress, initial elastic modulus, and evolution of the loading-unloading slope with plastic deformation were evaluated. Moreover, the kinematic contribution to the hardening was characterized by monotonic and cyclic simple shear test and reproduced by a mixed hardening law implemented in Abaqus finite element code. Then, the evolution of surface roughness with plastic strain, both in tension and simple shear, was analyzed. It was shown that in the case of an ultra-thin sheet, the stress levels, calculated either from an average thickness or when considering the effect of the surface roughness, exhibit a significant difference. Finally, the influence of surface roughness on the fracture of a tensile specimen was also investigated.

  5. Modeling of glycerol-3-phosphate transporter suggests a potential 'tilt' mechanism involved in its function.

    Science.gov (United States)

    Tsigelny, Igor F; Greenberg, Jerry; Kouznetsova, Valentina; Nigam, Sanjay K

    2008-10-01

    Many major facilitator superfamily (MFS) transporters have similar 12-transmembrane alpha-helical topologies with two six-helix halves connected by a long loop. In humans, these transporters participate in key physiological processes and are also, as in the case of members of the organic anion transporter (OAT) family, of pharmaceutical interest. Recently, crystal structures of two bacterial representatives of the MFS family--the glycerol-3-phosphate transporter (GlpT) and lac-permease (LacY)--have been solved and, because of assumptions regarding the high structural conservation of this family, there is hope that the results can be applied to mammalian transporters as well. Based on crystallography, it has been suggested that a major conformational "switching" mechanism accounts for ligand transport by MFS proteins. This conformational switch would then allow periodic changes in the overall transporter configuration, resulting in its cyclic opening to the periplasm or cytoplasm. Following this lead, we have modeled a possible "switch" mechanism in GlpT, using the concept of rotation of protein domains as in the DynDom program17 and membranephilic constraints predicted by the MAPAS program.(23) We found that the minima of energies of intersubunit interactions support two alternate positions consistent with their transport properties. Thus, for GlpT, a "tilt" of 9 degrees -10 degrees rotation had the most favorable energetics of electrostatic interaction between the two halves of the transporter; moreover, this confirmation was sufficient to suggest transport of the ligand across the membrane. We conducted steered molecular dynamics simulations of the GlpT-ligand system to explore how glycerol-3-phosphate would be handled by the "tilted" structure, and obtained results generally consistent with experimental mutagenesis data. While biochemical data remain most consistent with a single-site alternating access model, our results raise the possibility that, while the

  6. Potassium channel and NKCC cotransporter involvement in ocular refractive control mechanisms.

    Directory of Open Access Journals (Sweden)

    Sheila G Crewther

    Full Text Available Myopia affects well over 30% of adult humans globally. However, the underlying physiological mechanism is little understood. This study tested the hypothesis that ocular growth and refractive compensation to optical defocus can be controlled by manipulation of potassium and chloride ion-driven transretinal fluid movements to the choroid. Chicks were raised with +/-10D or zero power optical defocus rendering the focal plane of the eye in front of, behind, or at the level of the retinal photoreceptors respectively. Intravitreal injections of barium chloride, a non-specific inhibitor of potassium channels in the retina and RPE or bumetanide, a selective inhibitor of the sodium-potassium-chloride cotransporter were made, targeting fluid control mechanisms. Comparison of refractive compensation to 5 mM Ba(2+ and 10(-5 M bumetanide compared with control saline injected eyes shows significant change for both positive and negative lens defocus for Ba(2+ but significant change only for negative lens defocus with bumetanide (Rx(SAL(-10D = -8.6 +/- .9 D; Rx(Ba2+(-10D = -2.9 +/- .9 D; Rx(Bum(-10D = -2.9 +/- .9 D; Rx(SAL(+10D = +8.2 +/- .9 D; Rx(Ba2+(+10D = +2.8 +/- 1.3 D; Rx(Bum(+10D = +8.0 +/- .7 D. Vitreous chamber depths showed a main effect for drug conditions with less depth change in response to defocus shown for Ba(2+ relative to Saline, while bumetanide injected eyes showed a trend to increased depth without a significant interaction with applied defocus. The results indicate that both K channels and the NKCC cotransporter play a role in refractive compensation with NKCC blockade showing far more specificity for negative, compared with positive, lens defocus. Probable sites of action relevant to refractive control include the apical retinal pigment epithelium membrane and the photoreceptor/ON bipolar synapse. The similarities between the biometric effects of NKCC inhibition and biometric reports of the blockade of the retinal ON response, suggest a

  7. [The progress of studies on intraocular lens implantation in cataract with high myopia].

    Science.gov (United States)

    Liu, Xue; Wan, Xiuhua

    2015-07-01

    With development of the technology of cataract surgery, combined phacoemulsification and intraocular lens implantation in cataract with high myopia has been widely carried out in clinical treatment. Due to the particularity of high myopia, phacoemulsification in patients with cataract and high myopia is difficult and has recently received a lot of attentions. In this paper, preoperative examinations, the selection of intraocular lenses, surgery methods and surgical complications of cataract surgery in patients with cataract and high myopia are briefly reviewed. PMID:26310259

  8. The challenges in improving outcome of cataract surgery in low and middle income countries

    OpenAIRE

    Robert Lindfield; Kalluru Vishwanath; Faustin Ngounou; Rohit C Khanna

    2012-01-01

    Cataract is the leading cause of blindness globally and surgery is the only known measure to deal with it effectively. Providing high quality cataract surgical services is critical if patients with cataract are to have their sight restored. A key focus of surgery is the outcome of the procedure. In cataract surgery this is measured predominantly, using visual acuity. Population- and hospital-based studies have revealed that the visual outcome of cataract surgery in many low and middle income ...

  9. Molecular mechanisms involved in adaptive responses to radiation, UV light, and heat

    International Nuclear Information System (INIS)

    Viable organisms recognize and respond to environmental changes or stresses. When these environmental changes and their responses by organisms are extreme, they can limit viability. However, organisms can adapt to these different stresses by utilizing different possible responses via signal transduction pathways when the stress is not lethal. In particular, prior mild stresses can provide some aid to prepare organisms for subsequent more severe stresses. These adjustments or adaptations for future stresses have been called adaptive responses. These responses are present in bacteria, plants and animals. The following review covers recent research which can help describe or postulate possible mechanisms which may be active in producing adaptive responses to radiation, ultraviolet light, and heat. (author)

  10. Human lens colouration, age and cataract

    International Nuclear Information System (INIS)

    Full text: The human lens biosynthesises UV filter compounds which effectively remove light in the 300-400nm band. These chemicals are present either as an aid to visual acuity, or to filter out damaging UV radiation. The primate UV filters are 3-hydroxykynurenine analogues derived from the metabolism of tryptophan. We have recently demonstrated that these endogenous UV filters are not innocuous, but are in fact capable of binding to proteins, including the crystalline proteins which make up the bulk of the lens. Thus, over time, the levels of protein - bound UV filters increase and this results in the human lens becoming progressively more yellow as we age. This colouration affects our colour vision and it may also be responsible for the brown colour of lenses which is the hallmark of age-related nuclear cataract. An understanding of the intrinsic instability of the endogenous UV filters, combined with changes in the internal transport of these and other small molecular weight compounds including antioxidants, such as glutathione, is allowing us to gain an insight into the processes responsible for the development of age-related cataract: the major cause of world blindness

  11. How to prevent endophthalmitis in cataract surgeries?

    Directory of Open Access Journals (Sweden)

    Kelkar Aditya

    2008-01-01

    Full Text Available Postoperative endophthalmitis is a very devastating complication and every step should be taken to reduce its occurrence. Unattended air conditioning filter systems are often the culprits and regular maintenance of the filters is of paramount importance. Shedders of pathogenic organisms amongst the theater personnel should be identified by regular screening and should be promptly treated. In addition to the use of Povidone iodine 5% solution in the conjunctival sac few minutes prior to surgery, proper construction of wound, injectable intraocular lenses, use of prophylactic intracameral antibiotics or prophylactic subconjunctival antibiotic injection at the conclusion of cataract surgery, placing a patch after the surgery for at least 4 h and initiating topical antibiotics from the same day of surgery helps to lower the frequency of postoperative endophthalmitis. Intraoperative posterior capsule rupture and anterior vitrectomy are risk factors for acute endophthalmitis, and utmost care to prevent posterior capsular rent should be taken while performing cataract surgery. Also, in case of such complication, these patients should be closely monitored for early signs of endophthalmitis in the postoperative period. In the unfortunate event of endophthalmitis the diagnosis should be prompt and treatment must be initiated as early as possible.

  12. Endothelial trauma in the surgery of cataract

    Directory of Open Access Journals (Sweden)

    Đurović Branislav M.

    2004-01-01

    Full Text Available Cataract surgery is most common in human surgery and comprises 80% of eye surgery programs. Owing to sophisticated technologies, it has become a routine surgery with lowered complications rate; hence, the functional outcome is more conditioned by operative trauma. The aim of this study was to demonstrate the significance of specular microscopy in the evaluation of operative trauma during extra-capsular cataract extraction (ECCE and phacoemulsification (P, in a controlled environment. The study included 100 consecutive patients who met the established criteria, and groups were formed according to the type of surgery by the assignment of successive numbers from a random number table. Examination and photographs of the corneal endothelium, as well as pachymetry were performed on Keeler-Konan Poclington Specular Microscope (KSP. The obtained results revealed significant dissimilarity in endothelial cell reduction (9.17% in group E, and 4.72% in group P, which generated statistically significant correlation of pre-operative and post-operative pachymetry in the group E (p=0.0004. On the basis of the results obtained by specular microscopy, it was concluded that under the same conditions phacoemulsification caused reduced operative trauma of the corneal endothelium.

  13. Attentional Biases toward Attractive Alternatives and Rivals: Mechanisms Involved in Relationship Maintenance among Chinese Women.

    Science.gov (United States)

    Ma, Yidan; Zhao, Guang; Tu, Shen; Zheng, Yong

    2015-01-01

    A long-term romantic relationship can offer many benefits to committed individuals. Thus, humans possess relationship maintenance mechanisms to protect against threats from those who serve as attractive alternatives or intrasexual rivals. Many studies have indicated that romantic love can act as a commitment device to activate these mechanisms. To examine the attentional bias associated with relationship maintenance among 108 college students (49 single and 59 committed females) in China, we used a semantic priming procedure to activate mental representations associated with romantic love and then asked participants to complete a dot-probe task for the purpose of making a distinction between the engage and disengage components of attention. No significant engaging effects toward attractive faces were observed among committed females, but the following significant disengaging effects were found: when primed with romantic love, single females showed increased attention toward and difficulty in disengaging from attractive male faces, whereas females already in a committed relationship did not alter their attention, remaining as inattentive to attractive alternatives as they were in the baseline condition. In addition, committed females responded to love priming by exhibiting difficulty in disengaging from attractive rivals. The present findings provide evidence in the Chinese cultural context for the existence of early-stage attentional processes in the domain of relationship maintenance that committed Chinese females protected an ongoing relationship by not only being inattentive to attractive males who could serve as attractive alternatives, but also being more attentive to attractive females who could be potential rivals when mental representations associated with romantic love were primed. PMID:26309232

  14. A pathogenic mechanism in Huntington's disease involves small CAG-repeated RNAs with neurotoxic activity.

    Directory of Open Access Journals (Sweden)

    Mónica Bañez-Coronel

    Full Text Available Huntington's disease (HD is an autosomal dominantly inherited disorder caused by the expansion of CAG repeats in the Huntingtin (HTT gene. The abnormally extended polyglutamine in the HTT protein encoded by the CAG repeats has toxic effects. Here, we provide evidence to support that the mutant HTT CAG repeats interfere with cell viability at the RNA level. In human neuronal cells, expanded HTT exon-1 mRNA with CAG repeat lengths above the threshold for complete penetrance (40 or greater induced cell death and increased levels of small CAG-repeated RNAs (sCAGs, of ≈21 nucleotides in a Dicer-dependent manner. The severity of the toxic effect of HTT mRNA and sCAG generation correlated with CAG expansion length. Small RNAs obtained from cells expressing mutant HTT and from HD human brains significantly decreased neuronal viability, in an Ago2-dependent mechanism. In both cases, the use of anti-miRs specific for sCAGs efficiently blocked the toxic effect, supporting a key role of sCAGs in HTT-mediated toxicity. Luciferase-reporter assays showed that expanded HTT silences the expression of CTG-containing genes that are down-regulated in HD. These results suggest a possible link between HD and sCAG expression with an aberrant activation of the siRNA/miRNA gene silencing machinery, which may trigger a detrimental response. The identification of the specific cellular processes affected by sCAGs may provide insights into the pathogenic mechanisms underlying HD, offering opportunities to develop new therapeutic approaches.

  15. Attentional Biases toward Attractive Alternatives and Rivals: Mechanisms Involved in Relationship Maintenance among Chinese Women.

    Directory of Open Access Journals (Sweden)

    Yidan Ma

    Full Text Available A long-term romantic relationship can offer many benefits to committed individuals. Thus, humans possess relationship maintenance mechanisms to protect against threats from those who serve as attractive alternatives or intrasexual rivals. Many studies have indicated that romantic love can act as a commitment device to activate these mechanisms. To examine the attentional bias associated with relationship maintenance among 108 college students (49 single and 59 committed females in China, we used a semantic priming procedure to activate mental representations associated with romantic love and then asked participants to complete a dot-probe task for the purpose of making a distinction between the engage and disengage components of attention. No significant engaging effects toward attractive faces were observed among committed females, but the following significant disengaging effects were found: when primed with romantic love, single females showed increased attention toward and difficulty in disengaging from attractive male faces, whereas females already in a committed relationship did not alter their attention, remaining as inattentive to attractive alternatives as they were in the baseline condition. In addition, committed females responded to love priming by exhibiting difficulty in disengaging from attractive rivals. The present findings provide evidence in the Chinese cultural context for the existence of early-stage attentional processes in the domain of relationship maintenance that committed Chinese females protected an ongoing relationship by not only being inattentive to attractive males who could serve as attractive alternatives, but also being more attentive to attractive females who could be potential rivals when mental representations associated with romantic love were primed.

  16. Therapeutic targeting of myeloid-derived suppressor cells involves a novel mechanism mediated by clusterin.

    Science.gov (United States)

    Zhou, Junmin; Donatelli, Sarah S; Gilvary, Danielle L; Tejera, Melba M; Eksioglu, Erika A; Chen, Xianghong; Coppola, Domenico; Wei, Sheng; Djeu, Julie Y

    2016-01-01

    Myeloid-derived suppressor cells (MDSCs) constitute a key checkpoint that impedes tumor immunity against cancer. Chemotherapeutic intervention of MDSCs has gained ground as a strategy for cancer therapy but its mechanism remains obscure.We report here a unique mechanism by which monocytic (M)-MDSCs are spared, allowing them to polarize towards M1 macrophages for reactivation of immunity against breast cancer. We first demonstrated that curcumin, like docetaxel (DTX), can selectively target CD11b(+)Ly6G(+)Ly6C(low) granulocytic (G)-MDSCs, sparing CD11b(+)Ly6G(-)Ly6C(high) M-MDSCs, with reduced tumor burden in 4T1-Neu tumor-bearing mice. Curcumin treatment polarized surviving M-MDSCs toward CCR7(+) Dectin-1(-)M1 cells, accompanied by IFN-γ production and cytolytic function in T cells. Selective M-MDSC chemoresistence to curcumin and DTX was mediated by secretory/cytoplasmic clusterin (sCLU). sCLU functions by trapping Bax from mitochondrial translocation, preventing the apoptotic cascade. Importantly, sCLU was only found in M-MDSCs but not in G-MDSCs. Knockdown of sCLU in M-MDSCs and RAW264.7 macrophages was found to reverse their natural chemoresistance. Clinically, breast cancer patients possess sCLU expression only in mature CD68(+) macrophages but not in immature CD33(+) immunosuppressive myeloid cells infiltrating the tumors. We thus made the seminal discovery that sCLU expression in M-MDSCs accounts for positive immunomodulation by chemotherapeutic agents. PMID:27405665

  17. Therapeutic targeting of myeloid-derived suppressor cells involves a novel mechanism mediated by clusterin

    Science.gov (United States)

    Zhou, Junmin; Donatelli, Sarah S.; Gilvary, Danielle L.; Tejera, Melba M.; Eksioglu, Erika A.; Chen, Xianghong; Coppola, Domenico; Wei, Sheng; Djeu, Julie Y.

    2016-01-01

    Myeloid-derived suppressor cells (MDSCs) constitute a key checkpoint that impedes tumor immunity against cancer. Chemotherapeutic intervention of MDSCs has gained ground as a strategy for cancer therapy but its mechanism remains obscure.We report here a unique mechanism by which monocytic (M)-MDSCs are spared, allowing them to polarize towards M1 macrophages for reactivation of immunity against breast cancer. We first demonstrated that curcumin, like docetaxel (DTX), can selectively target CD11b+Ly6G+Ly6Clow granulocytic (G)-MDSCs, sparing CD11b+Ly6G−Ly6Chigh M-MDSCs, with reduced tumor burden in 4T1-Neu tumor-bearing mice. Curcumin treatment polarized surviving M-MDSCs toward CCR7+ Dectin-1−M1 cells, accompanied by IFN-γ production and cytolytic function in T cells. Selective M-MDSC chemoresistence to curcumin and DTX was mediated by secretory/cytoplasmic clusterin (sCLU). sCLU functions by trapping Bax from mitochondrial translocation, preventing the apoptotic cascade. Importantly, sCLU was only found in M-MDSCs but not in G-MDSCs. Knockdown of sCLU in M-MDSCs and RAW264.7 macrophages was found to reverse their natural chemoresistance. Clinically, breast cancer patients possess sCLU expression only in mature CD68+ macrophages but not in immature CD33+ immunosuppressive myeloid cells infiltrating the tumors. We thus made the seminal discovery that sCLU expression in M-MDSCs accounts for positive immunomodulation by chemotherapeutic agents. PMID:27405665

  18. Evolutionary mechanisms involved in the virulence of infectious salmon anaemia virus (ISAV), a piscine orthomyxovirus

    International Nuclear Information System (INIS)

    Infectious salmon anaemia virus (ISAV) is an orthomyxovirus causing a multisystemic, emerging disease in Atlantic salmon. Here we present, for the first time, detailed sequence analyses of the full-genome sequence of a presumed avirulent isolate displaying a full-length hemagglutinin-esterase (HE) gene (HPR0), and compare this with full-genome sequences of 11 Norwegian ISAV isolates from clinically diseased fish. These analyses revealed the presence of a virulence marker right upstream of the putative cleavage site R267 in the fusion (F) protein, suggesting a Q266 → L266 substitution to be a prerequisite for virulence. To gain virulence in isolates lacking this substitution, a sequence insertion near the cleavage site seems to be required. This strongly suggests the involvement of a protease recognition pattern at the cleavage site of the fusion protein as a determinant of virulence, as seen in highly pathogenic influenza A virus H5 or H7 and the paramyxovirus Newcastle disease virus

  19. Modelling and pathway identification involving the transport mechanism of a complex metabolic system in batch culture

    Science.gov (United States)

    Yuan, Jinlong; Zhang, Xu; Zhu, Xi; Feng, Enmin; Yin, Hongchao; Xiu, Zhilong

    2014-06-01

    The bio-dissimilation of glycerol to 1,3-propanediol (1,3-PD) by Klebsiella pneumoniae (K. pneumoniae) can be characterized by a complex metabolic system of interactions among biochemical fluxes, metabolic compounds, key enzymes and genetic regulation. In this paper, in consideration of the fact that the transport ways of 1,3-PD and glycerol with different weights across cell membrane are still unclear in batch culture, we consider 121 possible metabolic pathways and establish a novel mathematical model which is represented by a complex metabolic system. Taking into account the difficulty in accurately measuring the concentration of intracellular substances and the absence of equilibrium point for the metabolic system of batch culture, the novel approach used here is to define quantitatively biological robustness of the intracellular substance concentrations for the overall process of batch culture. To determine the most possible metabolic pathway, we take the defined biological robustness as cost function and establish an identification model, in which 1452 system parameters and 484 pathway parameters are involved. Simultaneously, the identification model is subject to the metabolic system, continuous state constraints and parameter constraints. As such, solving the identification model by a serial program is a very complicated task. We propose a parallel migration particle swarm optimization algorithm (MPSO) capable of solving the identification model in conjunction with the constraint transcription and smoothing approximation techniques. Numerical results show that the most possible metabolic pathway and the corresponding metabolic system can reasonably describe the process of batch culture.

  20. Genes and molecular mechanisms involved in the epileptogenesis of idiopathic absence epilepsies.

    Science.gov (United States)

    Yalçın, Ozlem

    2012-03-01

    Idiopathic absence epilepsies (IAE), that have high prevalence particularly among children and adolescents, are complex disorders mainly caused by genetic factors. Childhood absence epilepsy and juvenile absence epilepsy are among the most common subtypes of IAEs. While the role of ion channels has been the primary focus of epilepsy research, the analysis of mutation and association in both patients with absence epilepsies and animal models revealed the involvement of GABA receptors and calcium channels, but also of novel non-ion channel proteins in inducing spike wave discharges (SWD). Functional studies on a mutated variant of these proteins also support their role in the epileptogenesis of absence seizures. Studies in animal models point to both the thalamus and cortex as the origin of SWDs: the abnormalities in the components of these circuits leading to seizure activity. This review examines the current research on mutations and susceptibility alleles determined in the genes that code for the subunits of GABA receptors (GABRG2, GABRA1, GABRB3, GABRA5, GABA(B1) and GABA(B2)), calcium channels (CACNA1A, CACNA1G, CACNA1H, CACNA1I, CACNAB4, CACNAG2 and CACNG3), and novel non-ion channel proteins, taking into account the results of functional studies on these variants. PMID:22206818

  1. Transmission electron microscopy study of the reaction mechanisms involved in the carbothermal reduction of anatase

    International Nuclear Information System (INIS)

    The carbothermal reduction of anatase in titanium oxycarbide was studied by transmission electron microscopy (TEM). This study emphasizes that the reaction proceeds through complex solid–gas equilibria involving three main steps. During the first step, the carbon-monoxide-enriched atmosphere prevailing within the furnace provokes the direct transformation of anatase into the Magnéli phase. This transformation is accompanied by abnormal oxide grain growth showing a high number of stacking defects. The ordering tendency of such defects and their progressive increasing density lead to the final Ti3O5 compound. The second step of the reaction concerns the destabilization of Ti3O5 and carbon black in a high pCO atmosphere to form the oxycarbide. The titanium oxycarbide (TixOyCz) nucleates in the carbon black aggregates, giving rise to a first generation of defect-free faceted crystals (automorphous habit) characterized by a constant chemical composition. During the third step, Ti3O5 is missing and the primary carbide enters a maturation step characterized by carbon enrichment, attested by an increase in its cell parameter. This third step is characterized by the recrystallization phenomenon of the primary oxycarbide into the secondary one with an abrupt change in stoichiometry. The latter is characterized by rounded crystals (xenomorphous habit) bearing either a high density of dislocations or geometrical internal porosity linked to the migration of vacancies through the Kirkendall effect. Its further enrichment in carbon is assumed to be assisted by dislocation motion

  2. Risk of occupational radiation-induced cataract in medical workers

    International Nuclear Information System (INIS)

    The objective of this study was determination of criteria for recognition of a pre senile cataract as a professional disease in health care personnel exposed to small doses of ionizing radiation. Method: The study included 3240 health workers in medical centers of Serbia in the period 1992-2002. A total of 1560 workers were employed in the zone (group A) and 1680 out of ionizing radiation zone (group B). Among group A, two groups had been selected: 1. Group A-1: Health workers in the ionizing radiation zone who contracted lens cataract during their years of service while dosimetry could not reveal higher absorbed dose (A-1=115); 2. Group A-2: Health workers in the ionizing radiation zone with higher incidence of chromosomal aberrations and without cataract (A-2=100). Results: More significant incidence of cataract was found in group A, χ2=65.92; p<0.01. Radiation risk was higher in health workers in radiation zone than in others, relative risk is 4, 6. Elevated blood sugar level was found in higher percentage with health workers working in radiation zone who developed cataract. Conclusion: Low doses of radiation are not the cause of occupational cataract as individual occupational disease. X-ray radiation may be a significant cofactor of cataract in radiological technicians. (author)

  3. Time series analysis of age related cataract hospitalizations and phacoemulsification

    Directory of Open Access Journals (Sweden)

    Moineddin Rahim

    2006-01-01

    Full Text Available Abstract Background Cataract surgery remains a commonly performed elective surgical procedure in the aging and the elderly. The purpose of this study was to utilize time series methodology to determine the temporal and seasonal variations and the strength of the seasonality in age-related (senile cataract hospitalizations and phacoemulsification surgeries. Methods A retrospective, cross-sectional time series analysis was used to assess the presence and strength of seasonal and temporal patterns of age-related cataract hospitalizations and phacoemulsification surgeries from April 1, 1991 to March 31, 2002. Hospital admission rates for senile cataract (n = 70,281 and phacoemulsification (n = 556,431 were examined to determine monthly rates of hospitalization per 100,000 population. Time series methodology was then applied to the monthly aggregates. Results During the study period, age-related cataract hospitalizations in Ontario have declined from approximately 40 per 100,000 to only one per 100,000. Meanwhile, the use of phacoemulsification procedures has risen dramatically. The study found evidence of biannual peaks in both procedures during the spring and autumn months, and summer and winter troughs. Statistical analysis revealed significant overall seasonal patterns for both age-related cataract hospitalizations and phacoemulsifications (p Conclusion This study illustrates the decline in age-related cataract hospitalizations in Ontario resulting from the shift to outpatient phacoemulsification surgery, and demonstrates the presence of biannual peaks (a characteristic indicative of seasonality, in hospitalization and phacoemulsification during the spring and autumn throughout the study period.

  4. The Effect of Cataract on Eye Movement Perimetry

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    G. Thepass

    2015-01-01

    Full Text Available Purpose. To determine how different grades of cataract affect sensitivity threshold and saccadic reaction time (SRT in eye movement perimetry (EMP. Methods. In EMP, the visual field is tested by assessing the saccades that a subject makes towards peripheral stimuli using an eye tracker. Forty-eight cataract patients underwent pre- and postoperative EMP examination in both eyes. The subjects had to fix a central stimulus presented on the eye tracker monitor and to look at any detected peripheral stimulus upon its appearance. A multilevel mixed model was used to determine the factors that affected the sensitivity threshold and the SRT as a function of cataract grade. Results. We found no effect of cataract severity (LOCS III grades I through IV on SRT and the sensitivity thresholds. In cataract of LOCS III grade V, however, we found an increase by 27% and 21% (p<0.001, respectively, compared to the SRT and the sensitivity threshold in LOCS III grade I. Eyes that underwent cataract surgery showed no change in mean SRTs and sensitivity thresholds after surgery in LOCS III grade IV and lower. Conclusion. The present study shows that EMP can be readily used in patients with cataract with LOCS III grade IV and below.

  5. Role of cataract surgery in lowering intraocular pressure

    International Nuclear Information System (INIS)

    To study the effects of cataract surgery in lowering of intraocular pressure (IOP). Study Design: Retrospective study. Place and Duration of Study: The Department of Ophthalmology, Combined Military Hospital, Rawalpindi from January 2011 to December 2013. Patients and Methods: The study included a total of 250 patients; of which 100 cases had simple cataract with no coexisting disease, 100 cases had cataract with primary open angle glaucoma and 50 cases of cataract had accompanying pseudoexfoliation glaucoma. All patients were assessed and recorded preoperatively for their IOP, vision, depth of anterior chamber (ACD), angle of anterior chamber by gonioscopy and glaucoma medications being used. Cataract surgery was performed by phacoemulsification and IOL implantations in all cases. These patients were followed up for a period of six months. Results: The intraocular ressure of all these patients was recorded at monthly interval for six months. The IOP showed a significant decrease in all cases and remained constant till the end of the study. A marked improvement of vision was noted in all cases. The depth of the anterior chamber increased and the angle also widened in all cases. Discussion: Cataract surgery has been found to reduce IOP along with improvement in vision. Patients with glaucoma have a dual benefit of reduced IOP and visual improvement after cataract surgery. (author)

  6. Small incision cataract surgery: Complications and mini-review

    Directory of Open Access Journals (Sweden)

    Gogate Parikshit

    2009-01-01

    Full Text Available This article reviews the literature on manual small incision cataract surgery (MSICS and its complications. Various articles on MSICS published in indexed journals were reviewed, as well as the sections on complications of MSICS. The Pubmed search engine on the Internet was used to find out articles published since 1985 on MSICS in any language in indexed journals. Books published by Indian authors and the website of Indian Journal of Ophthalmology were also referred to. MSICS has become very popular technique of cataract surgery in India, and it is often used as an alternative to phacoemulsification. Studies on its efficacy and safety for cataract surgery show that, being a variant of extracapsular cataract surgery, MSICS also has similar intraoperative and postoperative complications. The considerable handling inside the anterior chamber during nucleus delivery increase the chances of iris injury, striate keratitis, and posterior capsular rupture. The surgeon has to be extra careful in the construction of the scleral tunnel and to achieve a good capsulorrhexis. Postoperative inflammation and corneal edema are rare if surgeons have the expertise and patience. The final astigmatism is less than that in the extracapsular cataract surgery and almost comparable to that in phacoemulsification. There is, however, a concern of posterior capsular opacification in the long term, which needs to be addressed. Although MSICS demands skill and patience from the cataract surgeon, it is a safe, effective, and economical alternative to competing techniques and can be the answer to tackle the large backlog of blindness due to cataract.

  7. Cataract research in India: A scientometric study of publications output, 2002-2011

    Directory of Open Access Journals (Sweden)

    KK Mueen Ahmed

    2014-10-01

    Full Text Available Analyses the 1293 Indian publications in cataract research during 2002-2011, with a focus on contribution and citation impact of 15 most productive countries, India's overall contribution, its growth, citation impact, the share of international collaborative papers, identification of significant countries in India's international collaboration, different types of cataract research, analyses of research by sub-fields and different population age groups, productivity, and impact of leading Indian institutions and authors and pattern of communication of Indian output in most productive journals. The Scopus Citation Database has been used to retrieve the data for 10 years (2002-2011. Indian publications increased from 87 papers in 2002 to 195 papers in 2011, witnessing an annual average growth rate of 10.03%, registering an average citation impact per paper of 3.26 and international collaborative share of 21.58% during 2002-2011. Suggest that the government should encourage the decision makers and ophthalmologists and allied persons involved in ophthalmic services to make serious efforts in reducing the burden of cataract disease by increasing the R&D, strengthening of national and international collaboration and improve the existing training programs for ophthalmologic professionals.

  8. Preoperative corneal astigmatism among adult patients with cataract in Northern Nigeria

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    Mohammed Isyaku

    2014-01-01

    Full Text Available The prevalence and nature of corneal astigmatism among patients with cataract has not been well-documented in the resident African population. This retrospective study was undertaken to investigate preexisting corneal astigmatism in adult patients with cataract. We analyzed keratometric readings acquired by manual Javal-Schiotz keratometry before surgery between January 1, 2011 and December 31, 2011. There were 3,169 patients (3286 eyes aged between 16 and 110 years involved with a Male to female ratio of 1.4:1. Mean keratometry in diopters was K1 = 43.99 and K2 = 43.80. Mean corneal astigmatism was 1.16 diopter and a majority (45.92% of eyes had astigmatism between 1.00 and 1.99 diopters. Two-thirds of the eyes (66.9% in this study had preoperative corneal astigmatism equal to or above 1.00 diopter. Findings will help local cataract surgeons to estimate the potential demand for toric intraocular lenses.

  9. Study of the physical mechanisms involved in the femtosecond laser optical breakdown of dielectric materials

    International Nuclear Information System (INIS)

    We have carried out detailed time resolved experimental studies of the mechanism of electron excitation-relaxation, when an ultrashort (60 fs-1 ps) laser (UV and IR) pulse interacts with a wide band gap dielectric material. The studies cover a range of different dielectric materials and the investigated regimes span from nondestructive ionization of the material at the low power end (∼TW/cm2) to ablative domain at a higher laser power (∼10 TW/cm2). This gives fundamental insight into the understanding of the laser damaging process taking place under our irradiation conditions. The usage of time-resolved spectral interferometry technique allows to directly measure the electron density of the irradiated material under different excitation conditions and hence leads to quantification of the process. The measurements, carried out at the optical breakdown threshold utilizing different pulse durations, raise questions regarding the usage of critical excitation density as a universal ablation criterion. A new criterion related to the exchanged energy is proposed. Additionally, the use of an experimental setup implementing a double pump pulse allows the identification of different excitation mechanisms taking place at time scales of the order of the pulse duration used. Electronic avalanche is observed in some materials (SiO2, NaCl) while this is not the case for others (Al2O3, MgO). These differences are discussed in detail. Next, we measure the energy spectrum of excited electrons with a complementary technique: the photoemission spectroscopy. These results allow us on one hand to show a crossed effect between the two 'pump' pulses and on the other hand to measure electron relaxation characteristic times, as a function of their kinetic energy. Finally, a morphological study of craters resulting from ablation in the case of a single pulse has been carried out for different irradiation parameters: number of shots, energy and pulse duration. This work has been extended

  10. Involvement of Epigenetic Mechanisms in the Regulation of Secreted Phospholipase A2 Expressions in Jurkat Leukemia Cells

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    Mario Menschikowski

    2008-11-01

    Full Text Available Epigenetic changes provide a frequent mechanism for transcriptional silencing of genes in cancer cells. We previously established that epigenetic mechanisms are important for control of group IIA phospholipase A2 (PLA2G2A gene transcription in human DU-145 prostate cells. In this study, we analyzed the involvement of such mechanisms in the regulation of five sPLA2 isozymes and the M-type receptor of sPLA2 (sPLA2-R in human leukemic Jurkat cells. These cells constitutively expressed sPLA2-IB, sPLA2-III, sPLA2-X, and sPLA2-R but not sPLA2-IIA and sPLA2-V. Transcription of sPLA2-IIA and sPLA2-V was, however, detected after exposure of cells to the DNA demethylating agent, 5-aza-2′-deoxycytidine (5-aza-dC. Expression of sPLA2-IIA was further enhanced by additional exposure to interferon-γ and blocked by inhibitors of specificity protein 1, nuclear factor κB, and Janus kinase/signal transducer and activator of transcription-dependent pathways. Sequence analysis and methylation-specific polymerase chain reaction of bisulfite-modified genomic DNA revealed two 5′-CpG sites (-111 and -82 in the sPLA2-IIA proximal promoter that were demethylated after 5-aza-dC treatment. These sites may be involved in the DNA binding of specificity protein 1 and other transcription factors. Similar findings after treatment of human U937 leukemia cells with 5-aza-dC indicate that this mechanism of PLA2G2A gene silencing is not restricted to Jurkat and DU-145 cells. These data establish that regulation of sPLA2-IIA and sPLA2-V in Jurkat and other cells involves epigenetic silencing by DNA hypermethylation.

  11. Sex differences in cerebellar mechanisms involved in pain-related safety learning.

    Science.gov (United States)

    Labrenz, Franziska; Icenhour, Adriane; Thürling, Markus; Schlamann, Marc; Forsting, Michael; Timmann, Dagmar; Elsenbruch, Sigrid

    2015-09-01

    Recent studies have suggested that the cerebellum contributes to the central processing of pain, including pain-related learning and memory processes. As a complex experience with multiple emotional and cognitive facets, the response to pain and its underlying neural correlates differ between men and women. However, it remains poorly understood whether and to what extent sex differences exist in the cerebellar contribution to pain-related associative learning processes. In the present conditioning study with experimental abdominal pain as unconditioned stimuli (US), we assessed sex-dependent differences in behavioral and neural responses to conditioned warning and safety cues in healthy volunteers. The results revealed that in response to visual stimuli signaling safety from abdominal pain (CS(-)), women showed enhanced cerebellar activation in lobules I-IV, V, VI, VIIIa, IX and X as well as Crus II and the dentate nucleus, which are mostly representative of somatomotor networks. On the other hand, men showed enhanced neural activation in lobules I-IV, VI, VIIb, VIIIb, IX as well as Crus I and II in response to CS(-), which are representative of frontoparietal and ventral attention networks. No sex differences were observed in response to pain-predictive warning signals (CS(+)). Similarly, men and women did not differ in behavioral measures of conditioning, including conditioned changes in CS valence and contingency awareness. Together, we could demonstrate that the cerebellum is involved in associative learning processes of conditioned anticipatory safety from pain and mediates sex differences in the underlying neural processes. Given the high prevalence of chronic pain conditions in women, these results may contribute to improve our understanding of the acquisition and manifestation of chronic abdominal pain syndromes. PMID:26004678

  12. Is the loss of endothelial thrombomodulin involved in the mechanism of chronicity in late radiation enteropathy?

    International Nuclear Information System (INIS)

    Background and purpose: Radiation enteropathy is characterized by locally elevated levels of inflammatory and fibrogenic c cytokines. Microvascular injury may sustain these alterations through persistent local hypercoagulopathy, platelet aggregation, leukocyte adhesion and release of biologically active mediators. This study assessed the relationship of endothelial thrombomodulin (TM), a key regulator of the protein C anticoagulant pathway and marker of endothelial function, with transforming growth factor β (TGF-β) immunoreactivity and morphologic alterations in radiation enteropathy. Materials and methods: Small bowel resection specimens from 9 patients with radiation enteropathy were analyzed by computerized quantitative immunohistochemistry using antibodies against TM, von Willebrand factor (vWF) and TGF-β. Identical measurements were performed on intestinal resection specimens from otherwise healthy penetrating trauma victims and on archived small intestines. A previously validated image analysis technique was used to assess submucosal vessels for TM and vWF immunoreactivity, and the intestinal wall for total extracellular matrix-associated TGF-β immunoreactivity. Results: Specimens from irradiated patients showed prominent submucosal and subserosal thickening and fibrosis, and obliterative vasculopathy. Control specimens were histopathologically normal. Vascular density and vWF immunoreactivity were similar in radiation enteropathy patients and controls. The image-analysis techniques were highly reproducible, with correlation coefficients for repeated measurements ranging from 0.86 to 0.93. Radiation enteropathy specimens exhibited a highly significant reduction in the number and proportion of TM-positive submucosal vessels per unit area (P < 0.0001) and increased intestinal wall TGF-β immunoreactivity (P = 0.002). Conclusions: These data support the theory that sustained endothelial dysfunction is involved in the molecular pathogenesis of radiation

  13. Clinical comparison of three techniques for evaluating visual function behind cataract.

    Science.gov (United States)

    Barrett, B T; Davison, P A; Eustace, P

    1995-01-01

    The aim of the study was to compare the ability of displacement threshold hyperacuity to identify reduced retinal/neural function in cataract patients with that of the potential acuity meter (PAM) and laser interferometer. Fifty-two patients (mean age 72.0 +/- 10.8 years) admitted for extracapsular cataract extraction were randomly selected for inclusion in the study. Patients underwent routine refraction and logMAR acuity measurement on the eve of cataract surgery. Following pupillary dilation and in random order, the oscillatory displacement threshold (ODT; defined as the smallest detectable displacement of an object) was determined, and predictions of the post-operative acuity were obtained using the PAM and Rodenstock Retinometer (RR). Patients were re-examined approximately 7 weeks post-operatively when logMAR acuities and ODTs were remeasured. On the basis of the results of an independent fundus examination, patients were assigned to either a normal or a pathology group. Increasing cataract density adversely affected the predictions provided by the PAM (p = 0.0001) and ODT (p = 0.0001) techniques, but not the RR (p = 0.137). One-factor ANOVA revealed that pre-operative ODT (p = 0.0001), PAM (p = 0.0001) and RR (p = 0.0004) measures successfully distinguished patients with retinal/neural pathology from normals. Pre-operative cut-off levels to distinguish normal from pathology cases were retrospectively determined for each technique. The cut-off values for the PAM and ODT techniques yielded higher sensitivity and specificity values than was the case for the RR. The results suggest that the predictive abilities of the PAM and ODT techniques are similar, and superior to that of the RR. Further work involving larger numbers of patients with posterior segment pathology is necessary to reveal which technique provides the best means of assessing retinal/neural function in the presence of ocular media opacities. PMID:8849539

  14. Studies of the mechanisms involved in the laser surface hardening process of aluminum base alloys

    International Nuclear Information System (INIS)

    The Al-Si alloys are widely used in industry to replace the steel and gray cast iron in high-tech sectors. The commercial importance of these alloys is mainly due to its low weight, excellent wear (abrasion) and corrosion resistance, high resistance at elevated temperatures, low coefficient of thermal expansion and lesser fuel consumption that provide considerable reduction of emission of pollutants. In this work, Al-Si alloy used in the automotive industry to manufacture pistons of internal combustion engines, was undergone to surface treatments using LASER remelting (Nd:YAG, λ = 1.06 μm, pulsed mode). The LASER enables various energy concentrations with accurate transfer to the material without physical contact. The intense energy transfer causes the occurrence of structural changes in the superficial layer of the material. Experiments with single pulses and trails were conducted under various conditions of LASER processing in order to analyze microstructural changes resulting from treatments and their effects on the hardness. For the characterization of hardened layer was utilized the following techniques: optical microscopy, scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), x-ray mapping, Vickers microhardness and maximum roughness tests. The high cooling rate caused a change in the alloy structure due to the refinement of the primary eutectic silicon particles, resulting in increase of the mechanical properties (hardness) of the Al-Si alloy. (author)

  15. Involvement of a joker mutation in a polymerase-independent lethal mutagenesis escape mechanism.

    Science.gov (United States)

    Agudo, Rubén; de la Higuera, Ignacio; Arias, Armando; Grande-Pérez, Ana; Domingo, Esteban

    2016-07-01

    We previously characterized a foot-and-mouth disease virus (FMDV) with three amino acid replacements in its polymerase (3D) that conferred resistance to the mutagenic nucleoside analogue ribavirin. Here we show that passage of this mutant in the presence of high ribavirin concentrations resulted in selection of viruses with the additional replacement I248T in 2C. This 2C substitution alone (even in the absence of replacements in 3D) increased FMDV fitness mainly in the presence of ribavirin, prevented an incorporation bias in favor of A and U associated with ribavirin mutagenesis, and conferred the ATPase activity of 2C decreased sensitivity to ribavirin-triphosphate. Since in previous studies we described that 2C with I248T was selected under different selective pressures, this replacement qualifies as a joker substitution in FMDV evolution. The results have identified a role of 2C in nucleotide incorporation, and have unveiled a new polymerase-independent mechanism of virus escape to lethal mutagenesis. PMID:27136067

  16. Radiotherapy for glioblastoma: reorganization of genome maintenance mechanisms involved in the process of inhibiting cancer

    International Nuclear Information System (INIS)

    Glioblastoma is a very aggressive brain tumor, which occurs in Glial cells. The treatment consists in chemotherapy, surgery and radiotherapy. The radiotherapy is a treatment method that uses ionizing radiation to kill cancer cells. The cells have genome maintenance mechanisms (MMG) distributed in apoptosis, DNA damage response, and cell cycle pathways. These pathways are formed by sets of proteins and perform specific functions within the cell (example: induce cell death). The mutation of these proteins associated with the failure of the MMG can cause the activation of mutations and consequently induce the development of cancer. This work, objective has to identify pathways and proteins expressed in cancer treatment using free software of the statistical analysis, developed in Fortran and R platforms to show the effects caused by radiation in the proteins of cancerous tissues. The results, were fond to pathways of glioblastoma treated with radiotherapy, activation of apoptosis and response to DNA damage pathways, indicating that there is death of carcinogenic tissue caused by radiation and that some cells are triggering a process of DNA repair. (author)

  17. Pathogenic mechanism of an autism-associated neuroligin mutation involves altered AMPA-receptor trafficking.

    Science.gov (United States)

    Chanda, S; Aoto, J; Lee, S-J; Wernig, M; Südhof, T C

    2016-02-01

    Neuroligins are postsynaptic cell-adhesion molecules that bind to presynaptic neurexins. Although the general synaptic role of neuroligins is undisputed, their specific functions at a synapse remain unclear, even controversial. Moreover, many neuroligin gene mutations were associated with autism, but the pathophysiological relevance of these mutations is often unknown, and their mechanisms of action uninvestigated. Here, we examine the synaptic effects of an autism-associated neuroligin-4 substitution (called R704C), which mutates a cytoplasmic arginine residue that is conserved in all neuroligins. We show that the R704C mutation, when introduced into neuroligin-3, enhances the interaction between neuroligin-3 and AMPA receptors, increases AMPA-receptor internalization and decreases postsynaptic AMPA-receptor levels. When introduced into neuroligin-4, conversely, the R704C mutation unexpectedly elevated AMPA-receptor-mediated synaptic responses. These results suggest a general functional link between neuroligins and AMPA receptors, indicate that both neuroligin-3 and -4 act at excitatory synapses but perform surprisingly distinct functions, and demonstrate that the R704C mutation significantly impairs the normal function of neuroligin-4, thereby validating its pathogenicity. PMID:25778475

  18. What Do Effective Treatments for Multiple Sclerosis Tell Us about the Molecular Mechanisms Involved in Pathogenesis?

    Directory of Open Access Journals (Sweden)

    Katherine A. Buzzard

    2012-10-01

    Full Text Available Multiple sclerosis is a potentially debilitating disease of the central nervous system. A concerted program of research by many centers around the world has consistently demonstrated the importance of the immune system in its pathogenesis. This knowledge has led to the formal testing of a number of therapeutic agents in both animal models and humans. These clinical trials have shed yet further light on the pathogenesis of MS through their sometimes unexpected effects and by their differential effects in terms of impact on relapses, progression of the disease, paraclinical parameters (MRI and the adverse events that are experienced. Here we review the currently approved medications for the commonest form of multiple sclerosis (relapsing-remitting and the emerging therapies for which preliminary results from phase II/III clinical trials are available. A detailed analysis of the molecular mechanisms responsible for the efficacy of these medications in multiple sclerosis indicates that blockade or modulation of both T- and B-cell activation and migration pathways in the periphery or CNS can lead to amelioration of the disease. It is hoped that further therapeutic trials will better delineate the pathogenesis of MS, ultimately leading to even better treatments with fewer adverse effects.

  19. Femtosecond laser cataract surgery: technology and clinical practice.

    Science.gov (United States)

    Roberts, Timothy V; Lawless, Michael; Chan, Colin Ck; Jacobs, Mark; Ng, David; Bali, Shveta J; Hodge, Chris; Sutton, Gerard

    2013-03-01

    The recent introduction of femtosecond lasers to cataract surgery has generated much interest among ophthalmologists around the world. Laser cataract surgery integrates high-resolution anterior segment imaging systems with a femtosecond laser, allowing key steps of the procedure, including the primary and side-port corneal incisions, the anterior capsulotomy and fragmentation of the lens nucleus, to be performed with computer-guided laser precision. There is emerging evidence of reduced phacoemulsification time, better wound architecture and a more stable refractive result with femtosecond cataract surgery, as well as reports documenting an initial learning curve. This article will review the current state of technology and discuss our clinical experience. PMID:22788831

  20. Ocular safety limits for 1030nm femtosecond laser cataract surgery

    Science.gov (United States)

    Wang, Jenny; Sramek, Christopher; Paulus, Yannis M.; Lavinsky, Daniel; Schuele, Georg; Anderson, Dan; Dewey, David; Palanker, Daniel V.

    2013-03-01

    Application of femtosecond lasers to cataract surgery has added unprecedented precision and reproducibility but ocular safety limits for the procedure are not well-quantified. We present an analysis of safety during laser cataract surgery considering scanned patterns, reduced blood perfusion, and light scattering on residual bubbles formed during laser cutting. Experimental results for continuous-wave 1030 nm irradiation of the retina in rabbits are used to calibrate damage threshold temperatures and perfusion rate for our computational model of ocular heating. Using conservative estimates for each safety factor, we compute the limits of the laser settings for cataract surgery that optimize procedure speed within the limits of retinal safety.

  1. Recombinant tissue plasminogen activator following paediatric cataract surgery

    OpenAIRE

    Mehta, J; ADAMS, G

    2000-01-01

    BACKGROUND—The use of recombinant tissue plasminogen activator (r-TPA) has been advocated in the treatment of postsurgical fibrinous membrane formation following cataract surgery in adults. Its use in paediatric cases is not well documented.
METHOD—A retrospective review of paediatric cataract extractions performed at Moorfields Eye Hospital between 1 January 1997 and 4 April 1999 was carried out.
RESULTS—Cataract extractions were performed in 37 patients, 22 in males 15 in females. Four (9.2...

  2. Aroclor 1254 causes atrophy of exocrine pancreas in mice and the mechanism involved.

    Science.gov (United States)

    Lin, Moudan; Wu, Tian; Sun, Lingbin; Lin, Jackie Jin; Zuo, Zhenghong; Wang, Chonggang

    2016-06-01

    Polychlorinated biphenyls (PCBs) are a class of organic pollutants that have been linked to pancreatic disease. However, their role in affecting the exocrine function of pancreas and the underlying mechanism remains elusive. In the present study, male C57 mice were treated with Aroclor 1254, a commercially available PCBs mixture, at a dosage of 0.5, 5, 50, or 500 μg kg(-1) every 3 days by oral gavage. Decrease in pancreas/soma index and acinar atrophy were observed in the mice after exposure for 50 days. Aroclor 1254 exposure significantly decreased the PCNA-positive cells in the pancreatic acini in a dose-dependent manner. In addition, western blot analysis showed that PCNA expression was decreased in pancreas in the presence of Aroclor 1254, which suggests that Aroclor 1254 suppresses cell proliferation. TUNEL-positive apoptotic cells as well as the expression of Bcl2, BclXL, BAX, and Bad of exocrine pancreas did not show significant changes in the treated mice, indicating that Aroclor 1254 has no effect on apoptosis. We also found that phosphorylation of ERK1/2, P90RSK1 and Bad was increased in the treated groups; this compensatory activation of phosphorylation in ERK1/2-P90RSK1-Bad signaling cascade could protect cell from apoptosis to maintain the cell numbers and function of exocrine pancreas. Moreover, we found that the expression of Kras and TNFα was increased in the pancreas, indicating that Aroclor 1254 exposure could result in increased risk of inflammation and carcinoma. © 2014 Wiley Periodicals, Inc. Environ Toxicol 31: 671-678, 2016. PMID:25409620

  3. Mechanisms of Binder Removal Involved in Supercritical Debinding of Injection Moulded Ceramics

    Science.gov (United States)

    Chartier, Thierry; Delhomme, Eric; Baumard, Jean-François

    1997-02-01

    Extraction of organic additives from extrusion-moulded ceramic parts by supercritical carbon dioxide has proved to be an efficient method for debinding [1,2]. A model of binder extraction based on diffusion equations was developed. This model was found to be in fair agreement with experimental results. Experimental kinetics of extraction of low melt point paraffins, by supercritical fluids, from injection-moulded samples are now established. A redistribution of the binder in the liquid state in the porosity of the sample, during supercritical debinding, is put in evidence. The importance of this mechanism and its influence on the validity of the model are discussed. Des études précédentes [1, 2] ont montré l'intérêt de l'extraction, à l'aide de gaz carbonique dans l'état supercritique, des additifs organiques de mise en forme de pièces céramiques. Elles ont permis de développer un modèle, établi à partir des équations de diffusion, qui est en bon accord avec les résultats expérimentaux. Les cinétiques expérimentales d'extraction, par fluide supercritique, de paraffines à bas point de fusion utilisées comme liant pour des compositions d'injection sont maintenant étudiées. Une redistribution du liant à l'état liquide au sein de la porosité de l'échantillon pendant le déliantage supercritique est mise en évidence. L'importance de ce mécanisme et son influence sur la validité du modèle sont discutées.

  4. Anorexic response to rapamycin does not appear to involve a central mechanism.

    Science.gov (United States)

    Toklu, Hale Z; Bruce, Erin B; Sakarya, Yasemin; Carter, Christy S; Morgan, Drake; Matheny, Michael K; Kirichenko, Nataliya; Scarpace, Philip J; Tümer, Nihal

    2016-09-01

    The authors have previously demonstrated that a low and intermittent peripheral dose of rapamycin (1 mg/kg three times/week) to rats inhibited mTORC1 signalling, but avoided the hyperlipidemia and diabetes-like syndrome associated with higher doses of rapamycin. The dosing regimen reduced food intake, body weight, adiposity, serum leptin and triglycerides. mTORC1 signalling was inhibited in both liver and hypothalamus, suggesting some of the actions, in particular the decrease in food intake, may be the results of a central mechanism. To test this hypothesis, rapamycin (30 μg/day for 4 weeks) was infused into 23-25-month-old F344xBN rats by intracerebroventricular (icv) mini pumps. Our results demonstrated that central infusion did not alter food intake or body weight, although there was a tendency for a decrease in body weight towards the end of the study. mTORC1 signalling, evidenced by decreased phosphorylation of S6 protein at end of 4 weeks, was not activated in liver, hypothalamus or hindbrain. Fat and lean mass, sum of white adipose tissues, brown adipose tissue, serum glucose, insulin and leptin levels remained unchanged. Thus, these data suggest that the anorexic and body weight responses evident with peripheral rapamycin are not the result of direct central action. The tendency for decreased body weight towards the end of study, suggests that there is either a slow transport of centrally administered rapamycin into the periphery, or that there is delayed action of rapamycin at sites in the brain. PMID:27232670

  5. Physiological and Molecular Mechanism of Nitric Oxide (NO Involved in Bermudagrass Response to Cold Stress.

    Directory of Open Access Journals (Sweden)

    Jibiao Fan

    Full Text Available Bermudagrass is widely utilized in parks, lawns, and golf courses. However, cold is a key factor limiting resource use in bermudagrass. Therefore, it is meaningful to study the mechanism of bermudagrass response to cold. Nitric oxide (NO is a crucial signal molecule with multiple biological functions. Thus, the objective of this study was to investigate whether NO play roles in bermudagrass response to cold. Sodium nitroprusside (SNP was used as NO donor, while 2-phenyl-4,4,5,5-tetramentylimidazoline-l-oxyl-3-xide (PTIO plus NG-nitro-L-arginine methyl ester (L-NAME were applied as NO inhibitor. Wild bermudagrass was subjected to 4 °C in a growth chamber under different treatments (Control, SNP, PTIO + L-NAME. The results indicated lower levels of malondialdehyde (MDA content and electrolyte leakage (EL, higher value for chlorophyll content, superoxide dismutase (SOD and peroxidase (POD activities after SNP treatment than that of PTIO plus L-NAME treatments under cold stress. Analysis of Chlorophyll (Chl a fluorescence transient displayed that the OJIP transient curve was higher after treatment with SNP than that of treated with PTIO plus L-NAME under cold stress. The values of photosynthetic fluorescence parameters were higher after treatment with SNP than that of treated with PTIO plus L-NAME under cold stress. Expression of cold-responsive genes was altered under cold stress after treated with SNP or PTIO plus L-NAME. In summary, our findings indicated that, as an important strategy to protect bermudagrass against cold stress, NO could maintain the stability of cell membrane, up-regulate the antioxidant enzymes activities, recover process of photosystem II (PSII and induce the expression of cold-responsive genes.

  6. Enhanced spontaneous locomotor activity in bovine GH transgenic mice involves peripheral mechanisms.

    Science.gov (United States)

    Bohlooly-Y, M; Olsson, B; Gritli-Linde, A; Brusehed, O; Isaksson, O G; Ohlsson, C; Söderpalm, B; Törnell, J; Ola, B

    2001-10-01

    Clinical and experimental studies indicate a role for GH in mechanisms related to anhedonia/hedonia, psychic energy, and reward. Recently we showed that transgenic mice with general overexpression of bovine GH display increased spontaneous locomotor activity. In the present study, we investigated whether this behavioral change is owing to a direct action of GH in the central nervous system or to peripheral GH actions. A transgenic construct, containing the glial fibrillary acidic protein promoter directing specific expression of bovine GH to the central nervous system, was designed. The central nervous system-specific expression of bovine GH in the glial fibrillary acidic protein-bovine GH transgenic mice was confirmed, but no effect on spontaneous locomotor activity was observed. Serum bovine GH levels were increased in glial fibrillary acidic protein-bovine GH transgenic mice but clearly lower than in transgenic mice with general overexpression of bovine GH. In contrast to the transgenic mice with general overexpression of bovine GH, glial fibrillary acidic protein-bovine GH mice did not display any difference in serum IGF-I levels. The levels of free T(3) and the conversion of the free T(4) to free T(3) were only increased in transgenic mice with general overexpression of bovine GH, but serum corticosterone levels were similarly increased in both transgenic models. These results suggest that free T(3) and/or IGF-I, affecting dopamine and serotonin systems in the central nervous system, may mediate the enhanced locomotor activity observed in transgenic mice with general overexpression of bovine GH. PMID:11564723

  7. The Vulnerability of Vessels Involved in the Role of Embolism and Hypoperfusion in the Mechanisms of Ischemic Cerebrovascular Diseases

    Directory of Open Access Journals (Sweden)

    Yong Peng Yu

    2016-01-01

    Full Text Available Accurate definition and better understanding of the mechanisms of stroke are crucial as this will guide the effective care and therapy. In this paper, we review the previous basic and clinical researches on the causes or mechanisms of ischemic cerebrovascular diseases (ICVD and interpret the correlation between embolism and hypoperfusion based on vascular stenosis and arterial intimal lesions. It was suggested that if there is no embolus (dynamic or in situ emboli, there might be no cerebral infarction. Three kinds of different clinical outcomes of TIA were theoretically interpreted based on its mechanisms. We suppose that there is a correlation between embolism and hypoperfusion, and which mechanisms (hypoperfusion or hypoperfusion induced microemboli playing the dominant role in each type of ICVD depends on the unique background of arterial intimal lesions (the vulnerability of vessels. That is to say, the vulnerability of vessels is involved in the role of embolism and hypoperfusion in the mechanisms of ischemic cerebrovascular diseases. This inference might enrich and provide better understandings for the underlying etiologies of ischemic cerebrovascular events.

  8. The Vulnerability of Vessels Involved in the Role of Embolism and Hypoperfusion in the Mechanisms of Ischemic Cerebrovascular Diseases

    Science.gov (United States)

    2016-01-01

    Accurate definition and better understanding of the mechanisms of stroke are crucial as this will guide the effective care and therapy. In this paper, we review the previous basic and clinical researches on the causes or mechanisms of ischemic cerebrovascular diseases (ICVD) and interpret the correlation between embolism and hypoperfusion based on vascular stenosis and arterial intimal lesions. It was suggested that if there is no embolus (dynamic or in situ emboli), there might be no cerebral infarction. Three kinds of different clinical outcomes of TIA were theoretically interpreted based on its mechanisms. We suppose that there is a correlation between embolism and hypoperfusion, and which mechanisms (hypoperfusion or hypoperfusion induced microemboli) playing the dominant role in each type of ICVD depends on the unique background of arterial intimal lesions (the vulnerability of vessels). That is to say, the vulnerability of vessels is involved in the role of embolism and hypoperfusion in the mechanisms of ischemic cerebrovascular diseases. This inference might enrich and provide better understandings for the underlying etiologies of ischemic cerebrovascular events.

  9. A novel GJA8 mutation (p.V44A causing autosomal dominant congenital cataract.

    Directory of Open Access Journals (Sweden)

    Yanan Zhu

    Full Text Available To examine the mechanism by which a novel connexin 50 (Cx50 mutation, Cx50 V44A, in a Chinese family causes suture-sparing autosomal dominant congenital nuclear cataracts.Family history and clinical data were recorded and direct gene sequencing was used to identify the disease-causing mutation. The Cx50 gene was cloned from a human lens cDNA library. Connexin protein distributions were assessed by fluorescence microscopy. Hemichannel functions were analyzed by dye uptake assay. Formation of functional channels was assessed by dye transfer experiments.Direct sequencing of the candidate GJA8 gene revealed a novel c.131T>C transition in exon 2, which cosegregated with the disease in the family and resulted in the substitution of a valine residue with alanine at codon 44 (p. V44A in the extracellular loop 1 of the Cx50 protein. Both Cx50 and Cx50V44A formed functional gap junctions, as shown by the neurobiotin transfer assay. However, unlike wild-type Cx50, Cx50V44A was unable to form open hemichannels in dye uptake experiments.This work identified a unique congenital cataract in the Chinese population, caused by the novel mutation Cx50V44A, and it showed that the V44A mutation specifically impairs the gating of the hemichannels but not the gap junction channels. The dysfunctional hemichannels resulted in the development of human congenital cataracts.

  10. Hydrogen-Rich Saline as an Innovative Therapy for Cataract: A Hypothesis.

    Science.gov (United States)

    Qin, Limin; Tao, Ye; Wang, Liqiang; Chen, Hong; Liu, Ying; Huang, Yi Fei

    2016-01-01

    Cataract is the leading cause of irreversible blindness worldwide. Increasing evidence indicates that oxidative stress is an important risk factor contributing to the development of cataract. Moreover, the enhancement of the antioxidant defense system may be beneficial to prevent or delay the cataractogenesis. The term oxidative stress has been defined as a disturbance in the equilibrium status of oxidant/antioxidant systems with progressive accumulation of reactive oxygen species (ROS) in intact cells. Superfluous ROS can damage proteins, lipids, polysaccharides, and nucleic acids within ocular tissues that are closely correlated with cataract formation. Therefore, prevention of oxidative stress damage by antioxidants might be considered as a viable means of medically offsetting the progression of this vision-impairing disease. Molecular hydrogen has recently been verified to have protective and therapeutic value as an antioxidant through its ability to selectively reduce cytotoxic ROS such as hydroxyl radical (OH). Hitherto, hydrogen has been used as a therapeutic element against multiple pathologies in both animal models and human patients. Unlike most well-known antioxidants, which are unable to successfully target organelles, hydrogen has advantageous distribution characteristics enabling it to penetrate biomembranes and diffuse into the cytosol, mitochondria, and nucleus. Consequently, we speculate that hydrogen might be an effective antioxidant to protect against lens damage, and it is important to further explore the biological mechanism underlying its potential therapeutic effects. PMID:27606690

  11. Preventive Effect of Zea mays L. (Purple Waxy Corn on Experimental Diabetic Cataract

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    Paphaphat Thiraphatthanavong

    2014-01-01

    Full Text Available Recently, substances possessing antioxidant can prevent cataractogenesis of diabetic cataract. Therefore, this study was carried out to determine the anticataract effect of Zea mays L. (purple waxy corn, a flavonoids rich plant, in experimental diabetic cataract. Enucleated rat lenses were incubated in artificial aqueous humor containing 55 mM glucose with various concentrations of Zea mays L. (purple waxy corn ranging between 2, 10, and 50 mg/mL at room temperature for 72 h. At the end of the incubation period, the evaluation of lens opacification, MDA level, and the activities of SOD, CAT, GPx, and AR in lens were performed. The results showed that both medium and high doses of extract decreased lens opacity together with the decreased MDA level. In addition, medium dose of extract increased GPx activity while the high dose decreased AR activity. No other significant changes were observed. The purple waxy corn seeds extract is the potential candidate to protect against diabetic cataract. The mechanism of action may occur via the decreased oxidative stress and the suppression of AR. However, further research in vivo is still essential.

  12. Chromic-P32 phosphate treatment of implanted pancreatic carcinoma: Mechanism involved

    Institute of Scientific and Technical Information of China (English)

    Lu Liu; Guo-Sheng Feng; Hong Gao; Guan-Sheng Tong; Yu Wang; Wen Gao; Ying Huang; Cheng Li

    2005-01-01

    AIM: To study the effects of chromic-P32 phosphate (32p colloids) interstitial administration in Pc-3 implanted pancreatic carcinoma, and investigate its anticancer mechanism.METHODS: Ninety-eight tumor bearing nude mice werekilled at different time points after the injection of 32Pcolloids to the tumor core with observed radioactivity. The light microscopy, transmission electron microscopy (TEM) and immuno-histochemistry and flow cytometry were used to study the rates of tumor cell necrosis, proliferating cell nuclear antigen index, the micro vessel density (MVD). The changes of the biological response to the lymphatic transported 32p colloids in the inguinal lymph node (ILN) were dynamically observed, and the percentage of tumor cell apoptosis, and Apo2.7, caspase-3, Bcl-2, Baxrelated gene expression were observed too.RESULTS: The half-life of effective medication is 13 dafter injection of 32P colloids to the tumor stroma, in 1-6groups, the tumor cell necrosis rates were 20%, 45%,65%, 70%, 95% and 4%, respectively (F= 4.14-105.36, P<0.01). MVD were 38.5±4.0, 28.0±2.9, 17.0±2.9, 8.8±1.5,5.7±2.3 and 65.0±5.2 (t= 11.9-26.1, P<0.01), respectively.Under TEM fairly differentiated Pc-3 cells were found. Thirty days after medication, tumors were shrunk and dried with scabs detached, and those in control group increased in size prominently with plenty of hypodermic blood vessels. In all animals the ILN were enlarged but in medicated animals they appeared later and smaller than those in control group. The extent of irradiative injury in ILN was positively correlated to the dosage of medication. Typical tumor cell apoptosis could be found under TEM inanimals with intra-tumoral injection of low dosed 32P colloids. The peak of apoptosis occurred in 2.96 MBq group and 24 h after irradiation. In the course of irradiationinduced apoptosis, the value of Bcl-2/Bax was down regulated; Apo2.7 and caspase-3 protein expression were prominently increased dose dependently

  13. Randomised, single-masked non-inferiority trial of femtosecond laser-assisted versus manual phacoemulsification cataract surgery for adults with visually significant cataract: the FACT trial protocol.

    OpenAIRE

    Day, A. C.; Burr, J.M.; Bunce, C; Doré, C J; Sylvestre, Y.; Wormald, R. P.; Round, J.; McCudden, V.; Rubin, G; Wilkins, M R

    2015-01-01

    INTRODUCTION: Cataract is one of the leading causes of low vision in the westernised world, and cataract surgery is one of the most commonly performed operations. Laser platforms for cataract surgery are now available, the anticipated advantages of which are broad and may include better visual outcomes through greater precision and reproducibility, and improved safety. FACT is a randomised single masked non-inferiority trial to establish whether laser-assisted cataract surgery is as good as o...

  14. Visco chop-a new technique for nucleus separation for soft cataracts in femtolaser assisted cataract surgery

    Institute of Scientific and Technical Information of China (English)

    Sri; Ganesh; Sheetal; Brar

    2015-01-01

    <正>INTRODUCTION Femtosecond laser technology,introduced clinically for ophthalmic surgery as a technique for creating lamellar flaps in laser in situ keratomileusis(LASIK),has recently been developed into a tool for cataract surgery.Preliminary experience for femtosecond laser-assisted cataract surgery show appropriate safety and efficacy,and possible advantage over conventional cataract surgery[1-4].The ability of the femtosecond laser to fragment the lens results in the need for less ultrasound energy to be expended inside the eye.Several studies indicate that less effective phacoemulsification time is needed to emulsify the lens

  15. Cataract surgery in a case of carotid cavernous fistula

    Directory of Open Access Journals (Sweden)

    Akshay Gopinathan Nair

    2014-01-01

    Full Text Available A carotid-cavernous fistula (CCF is an abnormal communication between the cavernous sinus and the carotid arterial system. The ocular manifestations include conjunctival chemosis, proptosis, globe displacement, raised intraocular pressure and optic neuropathy. Although management of CCF in these patients is necessary, the ophthalmologist may also have to treat other ocular morbidities such as cataract. Cataract surgery in patients with CCF may be associated with many possible complications, including suprachoroidal hemorrhage. We describe cataract extraction surgery in 60-year-old female with bilateral spontaneous low-flow CCF. She underwent phacoemulsification via a clear corneal route under topical anesthesia and had an uneventful postoperative phase and recovered successfully. Given the various possible ocular changes in CCF, one must proceed with an intraocular surgery with caution. In this communication, we wish to describe the surgical precautions and the possible pitfalls in cataract surgery in patients with CCF.

  16. The Effect of Cataract Surgery on Circadian Photoentrainment

    DEFF Research Database (Denmark)

    Brøndsted, Adam Elias; Sander, Birgit; Haargaard, Birgitte;

    2015-01-01

    of cataract surgery on circadian photoentrainment and to determine any difference between blue-blocking and neutral intraocular lenses (IOLs). DESIGN: The study was a single-center, investigator-driven, double-masked, block-randomized clinical trial. PARTICIPANTS: One eye in 76 patients with...... bilateral age-related cataract eligible for cataract surgery was included. METHODS: Intervention was cataract surgery by phacoemulsification. Patients were randomized to receive a blue-blocking or neutral IOL. MAIN OUTCOME MEASURES: Primary outcome was activation of intrinsic photosensitive ganglion cells...... (P = 0.004) for actigraphy and a tendency toward an earlier melatonin onset (P = 0.095) were found. Peak salivary melatonin concentration increased after surgery (P = 0.037). No difference was detected between blue-blocking and neutral IOLs, whereas low preoperative blue light transmission was...

  17. Cataract incidence in the cohort of occupationally exposed workers

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    E. V. Bragin

    2016-01-01

    Full Text Available Objective: To assess cataract incidence in the cohort of workers occupationally exposed to prolonged radiation. Material and Methods: Cataract incidence was studied in the cohort of workers of the first Russian nuclear enterprise — the Mayak, who were firstly employed at one of the main facilities (reactors, radiochemical and plutonium production plants in 1948‑1958 and followed up to the end of 2008 (12210 persons. Total of 3100 cataract cases were registered in the study cohort. All cataract cases were reviewed and verified by experts; the study included only confirmed senile cataracts. All workers of the study cohort were exposed to external gamma-rays; mean cumulative dose from external gamma-rays was 0.91±0.01 Gy in males and 0.65±0.01 Gy in females. Statistical analysis provided non-standardized and standardized incidence rates per 100 000 workers. Standardization by sex and age was performed by indirect method using internal reference.Results: 2523 cases of senile cataract were included in the study. Mean age of cataract diagnosis was 62.88±0.26 years in males and 64.88±0.28 years in females. Standardized incidence rates of cataract in females were significantly higher as compared to males and increased with workers age. Comparison between the subcohorts of workers with / without diagnosed cataracts demonstrated that among workers with cataracts the proportions of the following groups of workers were significantly higher: workers employed before 1954; workers employed at reactors; smoking workers; workers with the smoking index exceeding 20 pack*years; workers who consumed alcohol; workers with excessive body weight; workers with glaucoma and arterial hypertension. Moreover the mean cumulative dose from external gamma-rays and / or neutron exposure was significantly higher in the subcohort of workers diagnosed with cataracts than that in the subcohort of workers free of the disease. The highest cataract incidence

  18. LIPID PEROXIDATION AND LIPID PROFILE IN PATIENTS WITH SENILE CATARACT

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    Satya Devi

    2015-11-01

    Full Text Available : Lipid peroxidation products and biochemical parameters like fasting blood sugar and lipid profile were estimated in serum of 40 senile cataract cases (45-60 years and 40 persons of age and sex matched healthy controls. Plasma Thiobarbituric acid reactive substances (TBARS levels [as Malondialdehyde (MDA] were significantly higher in patients with senile cataract (573±64.4nmol/dl, P<0.001 as compared to healthy controls (378±31.31 nmol/dl. Serum cholesterol, Triglycerides, LDLC, VLDLC levels were increased as compared to controls. But HDLC levels were decreased in senile cataract patients as compared to controls. No significant change was observed in FBS values. The present study shows that the oxidative stress may play an important role in the senile cataract.

  19. Femtosecond laser-assisted cataract surgery: A current review

    Directory of Open Access Journals (Sweden)

    Majid Moshirfar

    2011-01-01

    Full Text Available To evaluate the safety, efficacy, advantages, and limitations of femtosecond laser-assisted cataract surgery through a review of the literature. A PubMed search was conducted using topic-appropriate keywords to screen and select articles. Initial research has shown appropriate safety and efficacy of femtosecond laser-assisted cataract surgery, with improvements in anterior capsulotomy, phacofragmentation, and corneal incision. Limitations of these studies include small sample size and short-term follow-up. Cost-benefit analysis has not yet been addressed. Preliminary data for femtosecond laser-assisted cataract surgery shows appropriate safety and efficacy, and possible advantage over conventional cataract surgery. Questions to eventually be answered include comparisons of long-term postoperative complication rates-including infection and visual outcomes-and analysis of contraindications and financial feasibility.

  20. Cataract surgery outcomes in a Tertiary Hospital, Riyadh

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    Bader Al-Qahtani

    2016-01-01

    Conclusion: Cataract removal is a safe and effective surgery which can improve the quality of life. It has some complications that can be minimised with good pre-operative evaluation and post-operative rehabilitation.

  1. Six year trend in cataract surgical techniques in Iran

    Directory of Open Access Journals (Sweden)

    Hassan Hashemi

    2011-01-01

    Full Text Available Purpose : To determine the cataract surgery techniques performed in Iran from 2000 to 2005. Materials and Methods : This study was part of the Iranian Cataract Surgery Survey (ICSS which was a retrospective cross-sectional study. All major ocular surgery units and 10% of randomly selected minor units throughout Iran were included. Excluding the 2 week Iranian New Year holiday, 1 week per season between 2000 and 2005 (a total of 24 weeks was selected for each center, and data on all cataract surgeries performed during these weeks were collected by reviewing patient records. The ANOVA repeated measure test was performed to determine longitudinal changes with a P0.05. Conclusion : Phacoemulsification with IOL implantation has become the preferred cataract surgery method in Iran during recent years.

  2. Visual loss in HIV-associated cryptococcal meningitis: A case series and review of the mechanisms involved

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    Anand Moodley

    2015-04-01

    Full Text Available Permanent visual loss is a devastating yet preventable complication of cryptococcal meningitis. Early and aggressive management of cerebrospinal fluid pressure in conjunction with antifungal therapy is required. Historically, the mechanisms of visual loss in cryptococcal meningitis have included optic neuritis and papilloedema. Hence, the basis of visual loss therapy has been steroid therapy and intracranial pressure lowering without clear guidelines. With the use of high-resolution magnetic resonance imaging of the optic nerve, an additional mechanism has emerged, namely an optic nerve sheath compartment syndrome (ONSCS caused by severely elevated intracranial pressure and fungal loading in the peri-optic space. An improved understanding of these mechanisms and recognition of the important role played by raised intracranial pressure allows for more targeted treatment measures and better outcomes. In the present case series of 90 HIV co-infected patients with cryptococcal meningitis, we present the clinical and electrophysiological manifestations of Cryptococcus-induced visual loss and review the mechanisms involved.

  3. Arbuscular Mycorrhizal Fungi for the Biocontrol of Plant-Parasitic Nematodes: A Review of the Mechanisms Involved

    Science.gov (United States)

    Schouteden, Nele; De Waele, Dirk; Panis, Bart; Vos, Christine M.

    2015-01-01

    Arbuscular mycorrhizal fungi (AMF) are obligate root symbionts that can protect their host plant against biotic stress factors such as plant-parasitic nematode (PPN) infection. PPN consist of a wide range of species with different life styles that can cause major damage in many important crops worldwide. Various mechanisms have been proposed to play a role in the biocontrol effect of AMF against PPN. This review presents an overview of the different mechanisms that have been proposed, and discusses into more detail the plausibility of their involvement in the biocontrol against PPN specifically. The proposed mechanisms include enhanced plant tolerance, direct competition for nutrients and space, induced systemic resistance (ISR) and altered rhizosphere interactions. Recent studies have emphasized the importance of ISR in biocontrol and are increasingly placing rhizosphere effects on the foreground as well, both of which will be the focal point of this review. Though AMF are not yet widely used in conventional agriculture, recent data help to develop a better insight into the modes of action, which will eventually lead toward future field applications of AMF against PPN. The scientific community has entered an exciting era that provides the tools to actually unravel the underlying molecular mechanisms, making this a timely opportunity for a review of our current knowledge and the challenges ahead. PMID:26635750

  4. EPHA2 polymorphisms and age-related cataract in India.

    Directory of Open Access Journals (Sweden)

    Periasamy Sundaresan

    Full Text Available OBJECTIVE: We investigated whether previously reported single nucleotide polymorphisms (SNPs of EPHA2 in European studies are associated with cataract in India. METHODS: We carried out a population-based genetic association study. We enumerated randomly sampled villages in two areas of north and south India to identify people aged 40 and over. Participants attended a clinical examination including lens photography and provided a blood sample for genotyping. Lens images were graded by the Lens Opacification Classification System (LOCS III. Cataract was defined as a LOCS III grade of nuclear ≥4, cortical ≥3, posterior sub-capsular (PSC ≥2, or dense opacities or aphakia/pseudophakia in either eye. We genotyped SNPs rs3754334, rs7543472 and rs11260867 on genomic DNA extracted from peripheral blood leukocytes using TaqMan assays in an ABI 7900 real-time PCR. We used logistic regression with robust standard errors to examine the association between cataract and the EPHA2 SNPs, adjusting for age, sex and location. RESULTS: 7418 participants had data on at least one of the SNPs investigated. Genotype frequencies of controls were in Hardy-Weinberg Equilibrium (p>0.05. There was no association of rs3754334 with cataract or type of cataract. Minor allele homozygous genotypes of rs7543472 and rs11260867 compared to the major homozygote genotype were associated with cortical cataract, Odds ratio (OR = 1.8, 95% Confidence Interval (CI (1.1, 3.1 p = 0.03 and 2.9 (1.2, 7.1 p = 0.01 respectively, and with PSC cataract, OR = 1.5 (1.1, 2.2 p = 0.02 and 1.8 (0.9, 3.6 p = 0.07 respectively. There was no consistent association of SNPs with nuclear cataract or a combined variable of any type of cataract including operated cataract. CONCLUSIONS: Our results in the Indian population agree with previous studies of the association of EPHA2 variants with cortical cataracts. We report new findings for the association with PSC which is

  5. The Tear Osmolarity Changes After Cataract Surgery

    Directory of Open Access Journals (Sweden)

    Banu Öncel

    2012-01-01

    Full Text Available Pur po se: To determine the tear osmolarity changes in patients who had undergone phacoemulsification surgery. Ma te ri al and Met hod: Tear osmolarity measurements were performed in 30 eyes of 30 patients who had undergone cataract surgery without any complication. Measurements were performed before surgery and consecutively at 1st month, 3rd month, and 6th month after the surgery. TearLab osmometer (TearLab Corporation, San Diego, CA, USA device was used for the measurements and paired ttest was used for statistical analysis. Re sults: The mean age of the patients was 72.3±3.7 (67-78 years. Thirteen patients were men and 17 patients were women. The mean osmolarity values were 305.8±6.5 mOsm/L before the surgery and 312.3±6.4 mOsm/L at 1st month, 307.5±5.1 mOsm/L at 3rd month and 305.1±5.7 at 6th month after the surgery. The difference between the values before surgery and at 1st month was found statistically significant (p=0.001. Dis cus si on: The tear osmolarity increases at the first month after surgery but decreases to the levels measured before surgery at the 3rd month. The increase at the first month may be due to the corneal incisions and medication used after the surgery. We think that we have to take into account this similarity increase in all cataract patients, especially in those who also have dry eye disease. (Turk J Ophthalmol 2012; 42: 35-7

  6. Visual experience during phacoemulsification cataract surgery under topical anaesthesia

    OpenAIRE

    Newman, D.

    2000-01-01

    BACKGROUND/AIMS—Visual awareness during phacoemulsification cataract surgery is an important determinant of patient satisfaction with any anaesthetic technique. Topical anaesthesia could be associated with significant visual awareness because it does not affect optic nerve function.
METHODS—The visual experience during phacoemulsification cataract surgery under topical anaesthesia (without sedation) was assessed for 106 consecutive unselected patients. Patients were interviewed immediately af...

  7. Convulsions during cataract surgery under peribulbar anesthesia: a case report

    OpenAIRE

    Bensghir, Mustapha; Badou, Najlae; Houba, Abdelhafid; Balkhi, Hicham; Haimeur, Charki; Azendour, Hicham

    2014-01-01

    Introduction Locoregional anesthesia techniques are increasingly used for cataract surgery. From these techniques, peribulbar anesthesia has been very successful over the retrobulbar anesthesia seen its effectiveness and safety. However, peribulbar anesthesia is not without risk. Case presentation A 70-year-old African man was scheduled for cataract surgery and lens implant for his right eye. His medical history included hypertension, diabetes mellitus and gall bladder surgery. There were no ...

  8. Evaluation of Complications of Extracapsular Cataract Extraction Performed by Trainees

    OpenAIRE

    Ezegwui, IR; Aghaji, AE; Okpala, NE; Onwasigwe, EN

    2014-01-01

    Background: Cataract extraction is the most common intraocular surgery taught to residents. Aim: This study aims to review the complications of trainee-performed extracapsular cataract extraction (ECCE) so as to identify the steps in which the trainee can benefit from closer supervision and practice. Subjects and Methods: This was a descriptive retrospective study of complications in the initial 150 ECCE with intraocular lens implant performed by two Ophthalmologists, from the University of N...

  9. New technology update: femtosecond laser in cataract surgery

    OpenAIRE

    Nagy ZZ

    2014-01-01

    Zoltan Z NagyDepartment of Ophthalmology, Semmelweis University, Budapest, HungaryAbstract: Femtosecond lasers represent a new frontier in cataract surgery. Since their ­introduction and first human treatment in 2008, a lot of new developments have been achieved. In this review article, the physical principle of femtolasers is discussed, together with the indications and side effects of the method in cataract surgery. The most important clinical results are also presented regarding c...

  10. New technology update: femtosecond laser in cataract surgery

    OpenAIRE

    Nagy, Zoltan

    2014-01-01

    Zoltan Z NagyDepartment of Ophthalmology, Semmelweis University, Budapest, HungaryAbstract: Femtosecond lasers represent a new frontier in cataract surgery. Since their ­introduction and first human treatment in 2008, a lot of new developments have been achieved. In this review article, the physical principle of femtolasers is discussed, together with the indications and side effects of the method in cataract surgery. The most important clinical results are also presented reg...

  11. Decrease and conquer: Phacoemulsification technique for hard nucleus cataracts.

    Science.gov (United States)

    Kim, Hong Kyun

    2009-10-01

    I describe a technique to improve the control and safety of phacoemulsification during hard nucleus cataract surgery. Whereas the goal of the conventional nucleofractis technique is complete fragmentation of the lens, the technique aims to separate the endonuclear core from the epinucleus. This is done in 3 steps: circumferential disassembly, decreasing the central nucleus volume, and conquering the remnant. The technique offers safer and more effective phacoemulsification in patients with hard nucleus cataracts. PMID:19781457

  12. PRE OPERATIVE CORNEAL ASTIGMATISM IN PATIENTS WITH CATARACT

    OpenAIRE

    Venkateswara Rao; Hanumantha Rao; Sivacharan; Anitha Devi

    2015-01-01

    AIM: To determine corneal astigmatism in patients with cataract posted for surgery. To achieve good visual outcome, significant corneal astigmatism has to be taken care of at the time of surgery either by corneal or limba l relaxing incisions or by implantation of toric intraocular lens. MATERIALS AND METHODS: This is a prospective observational case series conducted on 200 patients with cataract who attended the out - patient department of ophthalmology and c...

  13. "Vitreous loss: Incidence and complications in extracapsular Cataract extractions "

    OpenAIRE

    Nikeghbali A; Mirsamadi M; Hashemi M

    2000-01-01

    One of the dangerous complications of cataract extractions is vitreous loss. The purpose of this stuy is to evaluate the incidence of vitreous loss and its sepuale while teaching residents at Rasoul Akram Hospital in Iran. This study has been conducted on existing records of 730 eyes which were subjectd to extracapsular cataract extractions by 3rd and 4th year, right handed resident of Rasoul Akram hospital. The information was taken from the records of patients who had vitreous loss during c...

  14. Topical Anesthesia for Cataract Surgery: The Patients' Perspective

    OpenAIRE

    Aytekin Apil; Baki Kartal; Metin Ekinci; Halil Huseyin Cagatay; Sadullah Keles; Erdinc Ceylan; Ozgur Cakici

    2014-01-01

    Purpose. To evaluate the analgesic efficacy of 0.5% propacaine hydrochloride as topical anesthesia during phacoemulsification surgery. Methods. Intraoperative pain intensity was assessed using a 5-category verbal rating scale during each of three surgical stages. Pain scores from each surgical stage and total pain scores were compared for the factors of patient age, gender, cataract laterality, and type. Results. In comparison of cataract type subgroups, the mean total pain scores and mean st...

  15. Time series analysis of age related cataract hospitalizations and phacoemulsification

    OpenAIRE

    2006-01-01

    Background Cataract surgery remains a commonly performed elective surgical procedure in the aging and the elderly. The purpose of this study was to utilize time series methodology to determine the temporal and seasonal variations and the strength of the seasonality in age-related (senile) cataract hospitalizations and phacoemulsification surgeries. Methods A retrospective, cross-sectional time series analysis was used to assess the presence and strength of seasonal and temporal patterns of ag...

  16. Cataract surgery without anaesthesia: two descriptions by Arthur Jacob.

    Science.gov (United States)

    Haridas, R P

    2009-07-01

    Dr Arthur Jacob (1790-1874), of Dublin, Ireland, was one of the leading ophthalmologists of his time. He was the first to describe the membrane that contains the rods and cones in the eye (membrana Jacobi) and basal cell carcinoma (Jacob's ulcer). He made a curved needle for cataract surgery from a sewing needle (Jacob's needle). Two descriptions of cataract surgery without anaesthesia are presented. PMID:19705632

  17. TARGET EMMETROPIA IN MANUAL SMALL INCISION CATARACT SURGERY

    OpenAIRE

    Sathish; Prakash; Kanchana; Uma; Ambika A.; Amar; Mohan; Jafar,, T

    2013-01-01

    INTRODUCTION: Patient dissatisfaction is very common even with go od cataract surgery. Cataract surgery done by phacoemulsification with f oldable IOL implantation results in minimal astigmatism. This results in early rehabilitation t hereby rendering the patient nearly emmetropic for both distant and near work. But the drawbacks of this surgical technique are high cost, steep learning curve and is entirely mach ine dependent. This study has been conducted to ...

  18. Six year trend in cataract surgical techniques in Iran

    OpenAIRE

    Hassan Hashemi; Fatemeh Alipour; Shiva Mehravaran; Farhad Rezvan; Farshid Alaeddini; Akbar Fotouhi

    2011-01-01

    Purpose : To determine the cataract surgery techniques performed in Iran from 2000 to 2005. Materials and Methods : This study was part of the Iranian Cataract Surgery Survey (ICSS) which was a retrospective cross-sectional study. All major ocular surgery units and 10% of randomly selected minor units throughout Iran were included. Excluding the 2 week Iranian New Year holiday, 1 week per season between 2000 and 2005 (a total of 24 weeks) was selected for each center, and data on all cat...

  19. Effect of Cataract Surgery With Phacoemulsification on Diabetic Retinopathy

    OpenAIRE

    BİRİNCİ, H.; SEZGİN, S.; OGE, I.

    2009-01-01

    To asses the influence of cataract surgery and posterior chamber intraocular lens implantation on retinopathy progression, and visual acuity in patients with different stages of diabetic retinopathy (DR). Ninety-three eyes of 76 patients with or without diabetic retinopathy were evaluated prospectively following cataract extraction with posterior chamber intraocular lens implantation between January 1995 and December 2000. The ocular findings were recorded on each follow-up visits for at l...

  20. MRSA and cataract surgery – reflections for practice

    OpenAIRE

    Porter, LF; Khan, RU; Hannan, A.; Kelly, SP

    2010-01-01

    Introduction Postoperative bacterial endophthalmitis is a devastating complication of cataract surgery. Methicillin-resistant Staphylococcus aureus (MRSA) endophthalmitis is rare. Recent debate over MRSA screening in United Kingdom (UK) National Health Service (NHS) hospital services has implications for cataract patients and ophthalmology services. Aims To discuss issues for clinical practice as based on reflective experience at a UK district general NHS hospital in relation to care of MRSA-...