Ontogeny and tissue specific expression profiles of recombination activating genes (RAGs) during development in Nile tilapia, Oreochromisniloticus.

Recombination activating genes (RAGs) mediates the process of rearrangement and somatic recombination (V(D)J) to generate different antibody repertoire. Studies on the expression pattern of adaptive immune genes during ontogenic development are crucial for the formulation of fish immunization strategy. In the present study, Nile tilapia was taken to explore the relative expression profile of RAG genes during their developmental stages. The developmental stages of Nile tilapia, i.e., unfertilized egg, 0, 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, 28 and 30 days post-hatch (dph) and kidney, blood, gill, liver and spleen tissues from adult fish were collected and the cDNA synthesis was carried out. Gene specific primers for RAG-1 and RAG-2 of Nile tilapia were designed and their annealing temperature (Tm) was optimized by gradient PCR. Consequently, PCR was performed to confirm the specific amplification of RAG-1 and RAG-2 genes. Quantitative real-time PCR (qRT-PCR) gene expression of RAG-1 and RAG-2 were noticed in all the developmental stages; however, a significant increase was observed after 12 dph and peaked at 24 dph, followed by a gradual decrease until 30 dph. Tissue-specific gene expression profiling revealed that the highest expression of RAG-1 and RAG-2 was observed in the kidney, followed by spleen, gill, liver and blood. The findings of the study explored the suitable timing of lymphoid maturation that could be technically used for the adoption of strategies to improve disease resistance of fish larvae for mitigating larval mortality.

Comparative analysis of gut microbiome in Pangasionodon hypopthalmus and Labeo catla during health and disease.

The present study was conducted to study the composition of gut microbiome in the advanced fingerling and fingerling stage of striped pangasius catfish and catla during healthy and diseased conditions. Healthy pangasius and catla fishes were obtained from commercial farms and injected with the LD50 dose of A. hydrophila. The intestinal samples from the control and injected group were collected and pooled for 16 s metagenomic analysis. Community analysis was performed by targeting the 16 s rRNA gene to explore and compare the gut microbiota composition of these fishes. The operational taxonomic units (OTUs) consisted of four major phyla: Bacteroidia, Proteobacteria, Firmicutes, and Actinobacteria. Alpha and beta diversity indices were carried out to understand the diversity of microbes within and between a sample. While comparing the advanced fingerling and fingerling stage gut microbiome of Pangasius catfish, the dominance of Proteobacteria was found in fingerlings, whereas Firmicutes and Bacteroides were found in advanced fingerlings. In catla, Proteobacteria and Bacteroides were predominant. Taxonomic abundance of the microbiota in control and diseased Pangasius and catla fishes at phylum, class, order, family, genus, and species levels were also depicted. The present study is the first of its kind, and it will help to identify the diversity of novel potential bacterial species involved in disease protection of fishes. It can lead to the development of sustainable prophylactic measures against (re-)emerging bacterial diseases in aquaculture.

Selenium and mercury concentration, Se/Hg molar ratio and risk-benefit assessment of marine fish consumption: Human health risks and protective role of Se against Hg toxicity.

This study aimed to explore the concentrations of Se and Hg in marine fish along the Gulf of Mannar (southeast coast of India) and to assess related risks and risk-based consumption limits for children, pregnant women, and adults. Se concentrations in pelagic and benthic fish ranged from 0.278 to 0.470 mg/kg and 0.203 to 0.294 mg/kg, respectively, whereas Hg concentrations ranged from 0.028 to 0.106 mg/kg and 0.026 to 0.097 mg/kg, respectively. Se and Hg contents in demersal fish (Nemipterus japonicus) were 0.282 and 0.039 mg/kg, respectively. The lowest and highest Hg concentrations in pelagic fish were found in Scomberomorus commersoni and Euthynnus affinis whereas the lowest and highest Se concentrations in benthic fish were found in Scarus ghobban and Siganus javus. Se concentrations in marine fishes were found in the following order: pelagic > demersal > benthic whereas Hg concentrations were found in the following order: pelagic > benthic > demersal. The presence of Se in fish was positively correlated with trophic level (TL) and size whereas that of Hg was weakly correlated with TL and habitat and negatively correlated with size. Se risk-benefit analysis, the AI/RDI (actual intake/recommended daily intake) ratio was > 100 % and the AI/UL (upper limit) ratio was < 100 %, indicating that all fish have sufficient levels of Se to meet daily requirements without exceeding the UL. Hg level was below the maximum residual limit (MRL) of 0.5 mg/kg for most fish but it was 1 mg/kg in E. affinis and Lethrinus lentjan. The target hazard quotient (THQ < 1) and hazard index (HI < 1) imply that the consumption of fish poses no noncarcinogenic health risks. However, all examined fish had a mean Se/Hg molar ratio > 1, indicating that human intake of fishwas rather safe relative to Hg content. Health benefit indexes (Se-HBV and HBVse) with high positive values in all fish supported the protective effect of Se against Hg toxicity, suggesting the overall safety of fish consumption. The high Se/Hg ratio in fish could be attributed to the replacement of Se bound to Hg, thereby suppressing Hg toxicity and maintaining normal selenoprotein synthesis. This insight is useful for a better understanding of food safety analysis.

Myxozoan fish diseases: possible treatment and zoonoses.

Myxozoan parasites pose huge threat to wild and cultured fishes and reported to cause heavy mortality, retarded growth and post-harvest quality degradation. It is one of the highly divergent groups of parasites which infects skin, gill, muscle, cartilage and internal organs of host fish and the severity of pathology varies depending on the water temperature, species of fish, site of tissue infection and immune resistance of the individual host. Most infections are difficult to treat, as they can easily evade host cellular and humoral defence mechanisms by proliferating or migrating through immune compromised sites of the host and forming large plasmodia encapsulated by the host cellular elements. This spore-forming parasite is harmless to humans but often detected in faecal samples of immunosuppressed humans. The incidences are mostly associated with the consumption of infected fish having a high concentration of spores which causes diarrhea and stomach pain. Currently, there are no immunostimulants or vaccines available for controlling these parasites, however, fumagillin is the drug of choice in fish for controlling this parasitic infection. Excessive usage of fumagillin causes tissue damage and retarded growth in fish, hence feed incorporation of this antibiotic in proper dose is essential for effective treatment. In this review detailed information on the diseases caused by myxozoan parasites in fishes and their zoonotic potential is discussed.

Ocular leptospirosis: lack of awareness among ophthalmologists and challenges in diagnosis.

PURPOSE OF REVIEW: Systemic leptospirosis exists worldwide. But leptospiral uveitis, an important late complication is not identified by ophthalmologists in several countries. RECENT FINDINGS: In the last 18 months numerous publications, especially on epidemiology, surveillances, and novel rapid diagnostic kits to test at the point of care site on leptospirosis have been published from all over the world. However, publications from ophthalmologists are very scarce. Remarkably ophthalmologists should know the global burden of leptospirosis, prevalence of the disease in their country, demographic factors associated, risk factors, and systemic signs to elicit relevant history and travel history. They should be aware of recent advances in investigations to confirm their clinical diagnosis. SUMMARY: It is quite evident from this work that leptospirosis is prevalent worldwide. Ophthalmologists' awareness has to improve to identify the etiological diagnosis. They should have access to simple, less expensive, and less cumbersome laboratory tests.

Anterior Segment Ischemia in Viper Bite.

PURPOSE: To describe the clinical and histopathological features of post viper bite anterior segment ischemia. METHODS: Seven patients with ocular complications following viper bite referred to uveitis clinic had slit-lamp examination, intraocular pressure (IOP) measurement, and fundus evaluation. Iris and fundus fluorescein angiography was performed on 2 patients. Histopathological examination was performed on iris tissues collected during cataract surgery. RESULTS: Strikingly similar clinical findings were noted, including circumpupillary superficial iris atrophy, mid dilated fixed pupil, marked pigment dispersion, low IOP, and cataract. All clinical signs were noted only in the anterior segment; the posterior segment was normal. Histopathology of iris revealed atrophy of iris stroma, necrotic iris pigment epithelium, and infiltration of T lymphocytes and fibrous membrane. Poor visual outcome was noted in patients with low IOP. CONCLUSION: Viper bite victims presented with clinical and histopathological signs of anterior segment ischemia and secondary inflammatory signs mimicking uveitis.

Development and evaluation of NS1 specific monoclonal antibody based antigen capture ELISA and its implications in clinical diagnosis of West Nile virus infection.

BACKGROUND: West Nile virus (WNV) is a neurotropic flavivirus that causes viral encephalitis. Recent epidemics of WNV around the world have been associated with significant rates of mortality and morbidity in humans. The early confirmatory diagnosis of WNV infection is important for timely clinical management and epidemiological control in areas where multiple flaviviruses are endemic. OBJECTIVE: The aim of this study is to develop an monoclonal antibody based antigen capture ELISA for early confirmatory diagnosis of WNV infection with high degree of specificity and sensitivity having no cross reactivity with any of the closely related members of other circulating viruses. STUDY DESIGN: The gene coding for the NS1 protein of WNV was cloned and expressed in pET-28a expression vector. Purified recombinant protein was then utilized for generation of mice monoclonal antibody (Mab) and hyper immune sera (HIS) in rabbit. The sandwich ELISA was developed using the rabbit HIS and mice Mab as capture and detector antibody respectively and the results were compared with real time RT-PCR by evaluating 105 suspected clinical samples. RESULTS: The comparative evaluation of the sandwich ELISA with real time RT-PCR revealed 97% concordance with sensitivity and specificity of 90% and 98% respectively. CONCLUSION: The WN NS1 antigen was detectable in the blood from the first day up to day 9 after the onset of symptoms. The higher sensitivity and specificity of this monoclonal Antibody based sandwich ELISA makes it useful for early diagnosis of WN infection in endemic areas during outbreaks.

Molecular diagnosis and ocular imaging of West Nile virus retinitis and neuroretinitis.

PURPOSE: To describe the ocular features of West Nile virus (WNV) infection proven by serology and molecular diagnostic techniques. DESIGN: Prospective case series. PARTICIPANTS: Fifty-two patients who presented to the uveitis clinic with ocular inflammatory signs and history of fever preceding ocular symptoms between January 2010 and January 2012 were enrolled for laboratory diagnosis. Serum samples were collected from 30 healthy controls from the same geographic area. METHODS: Patients were tested for all endemic infectious diseases that can cause ocular inflammation by serology or molecular diagnostics. When patients had positive antibodies for WNV, serum/plasma samples were tested by real-time reverse transcription (RT) polymerase chain reaction (PCR) and RT loop-mediated isothermal gene amplification assays. The PCR product was subjected to nucleotide sequencing. Fundus fluorescence angiography (FFA), optical coherence tomography (OCT), and indocyanine green angiography were performed. Visual prognosis was analyzed. MAIN OUTCOME MEASURES: Clinical signs (retinitis, neuroretinitis, and choroiditis) and ocular complications (decrease in vision). RESULTS: A total of 37 of 52 patients (71%) showed positive results for at least 2 laboratory tests for WNV. Fundus examination revealed discrete, superficial, white retinitis; arteritis; phlebitis; and retinal hemorrhages with or without macular star. The FFA revealed areas of retinal inflammation with indistinct borders, vascular and optic disc leakage, vessel wall staining, or capillary nonperfusion. Indocyanine green angiography confirmed choroidal inflammation in 1 of the patients who was diabetic. The OCT scan of the macula revealed inner retinal layer edema in active inflammation and retinal atrophy in late stage. At the final visit, 43% of patients had visual acuity better than 6/12. CONCLUSIONS: In addition to previously reported clinical signs, retinitis, neuroretinitis, and retinal vasculitis were seen in this population. Atrophy of the inner retinal layer was seen on OCT after resolution of inflammation. Visual prognosis was good in patients with focal retinitis and poor in patients with occlusive vasculitis. FINANCIAL DISCLOSURE(S): The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Electrochemical oxidation of bisphenol-A from aqueous solution using graphite electrodes.

Electrochemical oxidation of bisphenol-A (BPA) from aqueous solution using graphite electrodes has been investigated. The effect of the types and concentration of supporting electrolytes, initial pH and applied current density on the performance of the process were examined. During electrolysis, concentration of BPA has been monitored and determined using UV-vis spectra, chemical oxygen demand (COD) and energy consumption. NaCl has been considered as the best supporting electrolyte among the electrolytes used in the present study. Initial pH 5.0, higher concentration (0.01 to 0.1 M) of supporting electrolyte and higher applied current density (4 to 20 mA cm(-2)) facilitate the treatment process. The maximum COD removal of 78.3% has been achieved under the optimal experimental conditions such as NaCl concentration of 0.05 M, applied current density of 12 mA cm(-2), initial pH 5.0 and electrolysis time of 120 min. When the energy consumption has been found to be decreasing with increasing NaCl concentration, it has increased with increasing applied current density. SEM-EDAX analysis has confirmed that the gases such as oxygen and chlorine are produced during the anodic oxidation in graphite anode. The result of UV-vis spectrum analysis confirms the degradation of BPA from aqueous solution at the end of the treatment.

Epiretinal deposits post cataract extraction.

PURPOSE: To report two unusual cases of epiretinal deposit post cataract surgery. METHODS: Retrospective identification of an unusual complication in patients who had cataract extraction recently with intraoperative complications. RESULTS: Two patients were identified with epiretinal deposits after cataract extraction where the posterior capsule barrier was breached. Inflammation was limited to the posterior segment, and investigative workup for infective causes was negative. No intraocular antibiotics had been used. In both the cases, hydroxypropyl methylcellulose was used as the viscoelastic substance. CONCLUSION: The authors report rare posterior segment toxicity in cataract surgeries complicated with intraoperative breach of posterior capsule barrier and hydroxypropyl methylcellulose use.

Serological diagnosis of leptospiral uveitis by HbpA IgG ELISA.

Leptospirosis is a zoonotic disease that is highly prevalent in tropical countries; uveitis is one of the manifestations of leptospirosis. The leptospiral aetiology of uveitis is difficult to predict because of overlapping clinical symptoms with uveitis due to other causes. The objective of this study was to evaluate the leptospiral haemin-binding protein HbpA as a diagnostic antigen for the serodiagnosis of leptospiral uveitis. Serum samples from patients, clinically diagnosed with leptospiral uveitis, were tested by ELISA for anti-HbpA antibodies and compared against the 'gold standard' microscopic agglutination test (MAT). Non-leptospiral uveitis and normal healthy individuals were used as controls. A total of 60 serum samples from patients suffering from leptospiral uveitis were studied, obtained from Aravind Eye Hospital, Madurai. Anti-HbpA IgG antibodies were detected in 92 % of patients clinically diagnosed with leptospiral uveitis, indicating that it is more sensitive than MAT, which had a seropositivity of only 50 %, and better than the commercially available Pan Bio IgM ELISA (81 %). The mean anti-HbpA antibody titre was significantly higher in leptospiral uveitis patients compared with controls (P<0.05). The antigen showed negligible cross-reactivity with non-leptospiral uveitis samples and cataract controls. We conclude that HbpA IgG ELISA identified cases of uveitis with leptospirosis aetiology and proved to be useful in differentiating them from other forms of uveitis.

Important role of integrins in the cancer biology.

Adhesion of breast cancer cells is supported by various integrins. Cell adhesion is critical for maintenance of both three-dimensional and normal function of these tissues. Several integrins have been shown to have higher expression levels in metastatic cancers and have been implicated in degrading basement membrane by interacting with proteolytic enzymes. This suggests that a group of integrins plays an important role in migration and invasion through the remodeling of the extracellular matrix. In this review, we highlight recent advances in our understanding of how integrins regulate breast cancer through modulation of the actin cytoskeleton and the mechanisms that regulate this process. Also, we highlight the importance of integrin-binding proteins in cell migration and mechanisms that operate in invasive cells, during breast cancer progression.

Tethered cord syndrome in children with anorectal malformations.

OBJECT: Anorectal malformations are known to be associated with neurological deficits, which may contribute to the disability suffered by patients with these malformations. This study was undertaken to determine the incidence and pattern of sacral abnormalities in children with anorectal malformations, the incidence and nature of the neurological deficits, and the incidence and nature of operable intraspinal abnormalities in patients with this condition. METHODS: Neurological evaluation was performed in 81 children with anorectal malformations. Plain x-ray films were obtained to identify the presence of sacral abnormalities. The patients with neurological deficits were evaluated for the presence of operable intraspinal anomalies, and when such anomalies were identified, correction of the same was undertaken. In 21% of these children radiographic evidence of sacral abnormalities was shown. Fifteen percent of patients harbored neurological deficits, and 10% harbored operable intraspinal anomalies. In addition, one patient had split notochord syndrome. Patients with operable intraspinal anomalies underwent surgical correction, with resultant neurological improvement. CONCLUSIONS: Bone abnormalities of the sacrum, neurological deficits, and operable intraspinal lesions are not uncommon in children with anorectal malformations. Because the neurological deficits can contribute to the disability suffered by these individuals, we recommend routine screening of patients with anorectal malformations and neurological deficits and/or sacral abnormalities for the early identification and treatment of potentially correctable intraspinal lesions.

Identification of Leptospira species in the pathogenesis of uveitis and determination of clinical ocular characteristics in south India.

Uveitis is considered a rare complication of leptospirosis. This report describes an epidemic of uveitis among patients with leptospirosis and provides data, using polymerase chain reaction (PCR) amplification of Leptospira DNA, that the pathogenesis is associated with anterior chamber spirochetes. Forty-six uveitis patients, 49 uveitis controls, and 54 cataract controls were enrolled at Aravind Eye Hospital (Madurai, India). Leptospiral DNA was detected by PCR of aqueous humor; serum antibody titers were determined by ELISA and microagglutination (MAT). Thirty-seven uveitis patients (80%) demonstrated leptospiral DNA compared with 5 controls (8%; P < .001). Thirty-three uveitis patients (72%) had positive serology compared with 10 uveitis controls (20%) and 13 cataract controls (24%; P < .001). This report describes the largest cluster of patients with leptospiral uveitis and identifies six clinical characteristics that provide a diagnostic profile for leptospiral uveitis. This profile will be important for determining treatment regimens in countries where PCR and MAT are not available.