Identification of Small Molecules for Prevention of Lens Epithelium-Derived Cataract Using Zebrafish.

Cataract is the leading cause of blindness worldwide. It can be treated by surgery, whereby the damaged crystalline lens is replaced by a synthetic lens. Although cataract surgery is highly effective, a relatively common complication named posterior capsular opacification (PCO) leads to secondary loss of vision. PCO is caused by abnormal proliferation and migration of residual lens epithelial cells (LECs) that were not removed during the surgery, which results in interruption to the passage of light. Despite technical improvements to the surgery, this complication has not been eradicated. Efforts are being made to identify drugs that can be applied post-surgery, to inhibit PCO development. Towards the goal of identifying such drugs, we used zebrafish embryos homozygous for a mutation in plod3 that develop a lens phenotype with characteristics of PCO. Using both biased and unbiased approaches, we identified small molecules that can block the lens phenotype of the mutants. Our findings confirm the relevance of zebrafish plod3 mutants' lens phenotype as a model for lens epithelium-derived cataract and add to our understanding of the molecular mechanisms that contribute to the development of this pathology. This understanding should help in the development of strategies for PCO prevention.

Dimethoate Induces DNA Damage and Mitochondrial Dysfunction Triggering Apoptosis in Rat Bone-Marrow and Peripheral Blood Cells.

Dimethoate (DM) is an organophosphorus (OP) pesticide with wide use in the pest control. Its persistence in crops and soils could possibly cause adverse health consequences in humans as well as other non-target species. Since molecular studies confirming potential genotoxicity of DM have not been previously reported, the acute in vivo toxicological impact was evaluated in Wistar rats. Significant micronuclei induction and metaphase chromosome abnormalities in bone marrow cells exposed to three different DM doses (20, 40 and 60 mg/kg-bw) at multiple treatment durations (24, 48 and 72 h) indicated positive dose response relationship, confirming its genotoxic and cytotoxic potential. Significant mitotic index decrease was seen in dosed animals compared to vehicle control. The study used peripheral blood comet assay, indicating DM-mediated damage to DNA at all exposure levels in a time responsive manner. These assays were found to be an effective, precise, and fast technique with applied value in biomonitoring studies. Cell cycle and apoptosis along with mitochondrial membrane potential (MMP) in flow cytometric analyses confirmed DM exposure decreased MMP, affected the cell cycle, and inflicted DNA damage, which led to cellular apoptosis of leukocytes culminating into immunotoxic effects. The in silico experiments consequently augmented that DM showed acceptable binding energy value for Cyclin A2, suggesting that it could inhibit the cell cycle progression by inhibiting cyclin A2.

Unusual presentation of an intraventricular hydatid cyst as a bleeding cystic tumor: A case report and brief review.

Hydatid cysts constitute only 2% of all intracranial masses, commonly involve parenchyma and very rarely ventricles. Here, we report an unusual case of a primary, isolated intraventricular hydatid cyst that mimicked a tumor and presented as intraventricular hemorrhage with hydrocephalus in a boy, causing a diagnostic dilemma. Although, preoperative modalities like computed tomography, magnetic resonance image and serology generally help in establishing the diagnosis, but hydatid cysts with unusual localizations and atypical imaging findings may complicate the diagnosis and need be considered in the differential diagnosis of all cystic masses in all anatomic locations, especially in endemic areas, so as to reduce the patient morbidity and mortality.

Toxicogenetic evaluation of dichlorophene in peripheral blood and in the cells of the immune system using molecular and flow cytometric approaches.

Dichlorophene; a halogenated phenolic compound with wide applications as a fungicide, bactericide and antiprotozoan. Dichlorophene spray also has therapeutic use in the disease digital dermatitis. In guinea pigs, a few studies obtained mixed results in dicholorophene sensitization tests. In consideration of the fact, that the mechanism of its genotoxicity has not been adequately elucidated lead to present study assessing the acute in vivo toxicological impact in Rattus norvegicus. A systematic research has been made encompassing the use of molecular and flow cytometric approaches. The study was designed on blood cells for comet assay which revealed dichlorophene induced DNA damage in all exposures understandable in time dependent manner. The feasibility of this assay was also established as an effective, fast and accurate method with a great potential in biomonitoring. Contemporary molecular techniques were further engaged using leukocytes for the cell apoptosis/cycle and mitochondrial membrane potential employing propidium iodide staining and rhodamine 123 respectively. The effect on cell cycle phases and mitochondrial membrane permeability was analyzed through flow cytometry. These indicators exposed that dichlorophene decreased the mitochondrial membrane potential, altered the cell cycle and confirmed the DNA damage leading to apoptosis of the cells of the immune system accountable for immunotoxic effects of dichlorophene on rat leukocytes.

Genotoxicity and immunotoxic effects of 1,2-dichloroethane in Wistar rats.

Dichloroethane is widely used as a solvent, degreasing agent and in a variety of commercial products, and is known for being a ubiquitous contaminant in the environment. Important sources principally include the emissions from industrial processes, improper consumption, storage, and disposal methods. In view of the fact that the mechanism of its genotoxicity has not been satisfactorily elucidated, the acute in vivo toxicological impact is assessed in Rattus norvegicus. A systematic investigation has been made involving the use of conventional methods along with molecular and flow cytometric approaches. The micronucleus and chromosomal aberration frequencies were significantly elevated in bone marrow cells exposed to three concentrations at multiple treatment durations indicating positive time- and dose-response relationships. The mitotic index significantly decreased in similar concentrations in contrast to normal control. Separate studies were performed on blood cells for comet assay. It revealed dichloroethane-induced DNA damage in all exposures readily explainable in a dose- and time-dependent manner. Recent molecular techniques were further employed using leukocytes for the cell apoptosis/cycle and mitochondrial membrane potential employing propidium iodide staining and rhodamine-123, respectively. The effect on mitochondrial membrane permeability, cell cycle phases, and the DNA damage was analyzed through flow cytometry. These indicators revealed dichloroethane treatment decreased the mitochondrial membrane potential, affected the cell cycle, and confirmed the DNA damage, leading to apoptosis of the cells of the immune system responsible for immunotoxic effects of dichloroethane on rat leukocytes.

Combined in silico and in vivo studies shed insights into the acute acetylcholinesterase response in rat and human brain.

Combined in vivo and in silico studies were undertaken to gain insights into the change in mammalian brain acetylcholinesterase (AChE) activity under acute toxicity conditions in response to two representatives of organophosphates (OPs)--dichlorvos (DCV) and dimethoate (DM). In vivo experiments elucidated that DCV, at multiple sublethal doses for acute time periods, markedly reduced (10-25%) AChE activity, whereas with DM intoxication, a decrease in enzyme activity appeared to be lower, that is, (2-15%), in contrast to respective normal control (100%). Furthermore, a significant inhibition (P < 0.01) in the brain esterase activity was recorded for positive control animals treated with an alkylating agent-cyclophosphamide, with spontaneous reactivation at later time periods. In vivo results were further substantiated with in silico molecular docking analysis using "Autodock 4.2." The lowest binding energy obtained through the computational study strongly augment that DCV binds to brain AChE with greater affinity compared with DM with reference to ∆G and Ki values. Thus, the animal biochemical assay and computational assessment suggest that DM is better to be used over DCV. The precautionary antidote for exposed humans can be developed prior to dealing with OPs. The study will aid in efficacious and safe clinical use of the above-mentioned compounds.

Protective Effects of Quercetin against Dimethoate-Induced Cytotoxicity and Genotoxicity in Allium sativum Test.

The present investigation was directed to study the possible protective activity of quercetin-a natural antioxidant against dimethoate-induced cyto- and genotoxicity in meristematic cells of Allium sativum. So far there is no report on the biological properties of quercetin in plant test systems. Chromosome breaks, multipolar anaphase, stick chromosome, and mitotic activity were undertaken in the current study as markers of cyto- and genotoxicity. Untreated control, quercetin controls (@ 5, 10 and 20 µg/mL for 3 h), and dimethoate exposed groups (@ 100 and 200 µg/mL for 3 h) were maintained. For protection against cytogenotoxicity, the root tip cells treated with dimethoate at 100 and 200 µg/mL for 3 h and quercetin treatment at 5, 10, and 20 µg/mL for 16 h, prior to dimethoate treatment, were undertaken. Quercetin was found to be neither cytotoxic nor genotoxic in Allium sativum control at these doses. A significant increase (P < 0.05) in chromosomal aberrations was noted in dimethoate treated Allium. Pretreatment of Allium sativum with quercetin significantly (P < 0.05) reduced dimethoate-induced genotoxicity and cytotoxicity in meristematic cells, and these effects were dose dependent. In conclusion, quercetin has a protective role in the abatement of dimethoate-induced cyto- and genotoxicity in the meristematic cells of Allium sativum that resides, at least in part, on its antioxidant effects.

Assessment of genotoxic potential of the insecticide Dichlorvos using cytogenetic assay.

The possible genotoxic activity of Dichlorvos (2,2-Dichlorovinyl-O,O-dimethyl phosphate/DDVP, CAS No. 62-73-7), an organophosphorus insecticide was investigated employing three cytogenetic end points, i.e. micronucleus (MN) assay, mitotic indices (MI) and chromosome abberation (CA) analysis in vivo. The assays were carried out in hematopoietic bone marrow cells of Mus musculus at concentrations of 10, 20 and 30% of LD50 for intraperitoneal (ip) administration, corresponding to 0.06, 0.08 and 0.13 mg/kg Bwt, respectively. The normal control group received single ip dose of distilled water (2 ml/100 g Bwt), while animals of the positive group were injected with cyclophosphamide, a model mutagen (40 mg/kg Bwt) under identical conditions. The animals were sacrificed 24, 48 and 72 hrs post treatment. Under the present experimental conditions, there was no evidence of significant increase of MN frequencies at any dose or sampling time in polychromatic (PCE) and normochromatic (NCE) erythrocytes. The PCE/NCE ratio was not notably affected; however, a slight depression in prolonged exposure (48, 72 hr) intervals and a slight increase at the 24 hr interval were observed. Cells with various structural chromosome aberrations were noted but no significant (p<0.05; Man-Whitney U-test) differences in the frequencies of CA or mitotic indices (p<0.05; χ(2) test) were observed between Dichlorvos treated groups and the normal control group at doses or time intervals used. The results of the present investigation reflects a negative in vivo genotoxic potential of Dichlorvos at sublethal doses in bone marrow cells. Further studies are underway to confirm the presence or absence of genotoxic activity since compounds negative in genotoxic evaluation are susceptible of being carcinogens triggering cancer by genotoxic or non-genotoxic mechanisms.

Evidence of apoptosis in some cell types due to pentachlorophenol (PCP) in Heteropneustes fossilis.

The study aimed to clarify the role of apoptosis in pentachlorophenol (PCP) induced testicular, ovarian and renal cell genotoxicity of Heteropneustes fossilis. It was further intended to find the target germ cell type and assess the cellular and nuclear damage. Treatment of PCP was used for multiduration on the germinal tissues and they were processed to detect structural changes by light and electron microscopic evaluation and kidney cells for subsequent detection of DNA fragmentation by agarose gel electrophoresis. Findings suggest functional and morphological changes in the tissues are due to apoptosis, as evidenced by some biochemical and cytological signs. Histological observation on germinal epithelium reveals cell suicidal symptoms such as vacuolization, liquefied regions in the cytoplasm of oocytes, margination of nuclei, clumping of chromatin, and compaction of cytoplasmic organelle. Biochemical manifestation concurrent to this, is; cleavage of kidney cell DNA into low molecular weight fragments confirming apoptosis. Subsequently, it is further cleaved into nucleosome size fragments or its multiples. Ultra-structural histopathology and DNA studies conclusively lead to the PCP induced apoptosis in the exposed cell types. Results further support the usefulness of this assay in the related studies and its feasibility in generating a base line data.

Profile of lymphadenopathy in Kashmir valley: a cytological study.

Lymphadenopathy is one of the commonest and significant manifestations of local as well as systemic ailments, especially malignancies. Fine needle aspiration cytology (FNAC) helps in diagnosing the disease itself, in general, but more importantly ruling out malignancy, in particular. Hence it saves much of the cost and use of resources incurred with excision biopsy of such lymph nodes. This prompted us to study the cytologic patterns of lymphadenopathy in our setting and the diagnostic utility of FNAC in the evaluation of lymphadenopathy. In this retrospective observational study, 1,579 patients (953 males and 626 females) with lymphadenopathy who were subjected to FNAC over a period of three years (January 2009 to December 2011) were studied. The cervical region was involved in most of the cases (76%) followed by the axillary region (17.5%). Metastatic malignancy (38.2%) was the commonest cause of lymphadenopathy followed by reactive lymphoid hyperplasia (36.9%), tuberculosis (9.1%) and lymphomas (8.6%). Squamous cell carcinoma (32.2%) followed by adenocarcinoma (21.9%) were the most frequent metastatic tumors. FNAC is a useful diagnostic tool in the management of patients presenting with lymphadenopathy and should be considered before more invasive and costly procedures are performed, particularly in developing countries.

Phytoremediation of heavy metal polluted soils and water: progresses and perspectives.

Environmental pollution affects the quality of pedosphere, hydrosphere, atmosphere, lithosphere and biosphere. Great efforts have been made in the last two decades to reduce pollution sources and remedy the polluted soil and water resources. Phytoremediation, being more cost-effective and fewer side effects than physical and chemical approaches, has gained increasing popularity in both academic and practical circles. More than 400 plant species have been identified to have potential for soil and water remediation. Among them, Thlaspi, Brassica, Sedum alfredii H., and Arabidopsis species have been mostly studied. It is also expected that recent advances in biotechnology will play a promising role in the development of new hyperaccumulators by transferring metal hyperaccumulating genes from low biomass wild species to the higher biomass producing cultivated species in the times to come. This paper attempted to provide a brief review on recent progresses in research and practical applications of phytoremediation for soil and water resources.