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41.
Serum paraoxonase (PON1) is a high-density lipoprotein (HDL) associated protein, which plays a critical role in the pathogenesis of atherosclerosis, although it was primarily associated with the hydrolysis of organophosphorus compounds. PON1 was initially thought to be independent from physiological or pathological states, although recently some environmental factors have been reported to modulate its activity. In this study, we have investigated the promoter (PON1 -108C/T and -909 C/G) and coding region (PON1 192Q/R and 55L/M) polymorphisms, as well as PON1 activity towards different substrates (paraoxon, phenylacetate and diazoxon) in 102 individuals with long term low dose exposure to pesticides in a plastic greenhouse setting (sprayers), who are probably the group of agricultural workers with the highest exposure to pesticides. PON1 activity towards paraoxon was nonsignificantly decreased (up to 53.5%) in the sprayers subgroup exposed to organophosphates (n = 41) compared with nonsprayers acting as controls (n = 39). None of the genotypes studied was associated significantly with the subgroup of individuals exposed to organophosphates, although differences between sprayers and nonsprayers were observed in the PON1 -909 G/C polymorphism. Among the environmental factors that significantly predicted lower rates of PON1 activity towards paraoxon are, interestingly, the exposure to organophosphates and current smoking. By contrast, the utilization of protective clothing while spraying pesticides inside the greenhouses was positively associated with PON1 activity, very likely by preventing the pesticides from being absorbed. This study suggests that chronic exposure to pesticides might decrease PON1 activity and pinpoints the potential usefulness of monitoring PON1 activity in occupational settings where exposure to organophosphates occurs.  相似文献   
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A young male child presented with hypospadias. Examination revealed additional anomalies including hypertelorism and upslanting of palpebral fissures, suggesting a diagnosis of hypospadias-hypertelorism syndrome. The case is reported because of its rarity and some unusual features.  相似文献   
44.
Neuroendocrine carcinomas of the cervix are uncommon, characterized by a histomorphological spectrum and, mostly, an aggressive clinical course. There are only few substantial studies on such cases documented from our country, where cervical cancer is the second most common cancer affecting women. Herein, we present a spectrum of 50 cervical neuroendocrine carcinomas, including histopathologic features, terminology, immunohistochemical (IHC) profile, and clinical outcomes, wherever available. Fifty tumors occurred in women, with their age ranging from 23 to 69 years (mean, 48.6 years; median, 46.5 years). Stagewise, among 25 cases, most cases (6, or 24%) presented with stage IB. Average tumor size was 4.7 cm. On histopathologic review, 26 tumors (52%) were classified as small cell carcinoma (SMCA); 14 (28%), as large cell neuroendocrine carcinomas (LCNECs); 4 (8%), as SMCA + LCNECs; and 6, as mixed carcinomas, including 3 tumors (6%) with SMCA and squamous cell carcinoma (SCC), 2 tumors (4%) with LCNEC and adenocarcinoma, and a single tumor (2%) with LCNEC and squamous cell carcinoma. On IHC performed in 41 tumors (82%), 36 tumors (87.8%) were positive for at least a single neuroendocrine marker, and 22 (53.6%) expressed 2 neuroendocrine markers. Synaptophysin was positive in 22 (59.4%) of 37 tumors; chromogranin, in 27 (72.9%) of 37; CD56, in 8 (100%) of 8; and neuron-specific enolase in 7 (87.5%) of 8 tumors. Treatment wise, among 30 patients (60%), 6 (20%) underwent surgery, including Wertheim hysterectomy (5) and simple hysterectomy (1); 8 (26.6%) underwent surgery with adjuvant treatment, and 10 patients (33.3%) were offered chemotherapy and/or radiotherapy. On follow-up (27 patients, or 54%) over 1 to 144 months, 16 patients (59.2%) were alive with disease over median duration of 9 months, and 7 (25.9%) were free of disease over median duration of 26.5 months. There were 5 recorded deaths. Thirteen tumors (48.1%) metastasized, most commonly to liver. In cases with early stage disease and adjuvant treatment, including radiotherapy, LCNEC histology fared well. This study forms the largest documented series on cervical neuroendocrine carcinomas from our country, testifying the current histopathologic classification system. Although SMCAs can be recognized on morphology, LCNECs need to be correctly identified because these can be misdiagnosed in the absence of neuroendocrine markers. Synaptophysin, chromogranin, and CD56 are optimal IHC markers. Small cell carcinomas, pure or mixed, are relatively more aggressive. All these tumors are best treated with multimodal therapy. Early stage disease treated with radical surgery and adjuvant treatment seems to increase survival. Despite aggressive treatment, prognosis is dismal.  相似文献   
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Pheochromocytoma of urinary bladder is rare disease causing a hypertension, palpitation, throbbing headache & hemorrhage induced by voiding. This case is reported because of rarity of this disease in urinary bladder.  相似文献   
46.
Natural products for cancer prevention: a global perspective   总被引:7,自引:0,他引:7  
The control of cancer, the second leading cause of death worldwide, may benefit from the potential that resides in alternative therapies. The primary carcinogens stem from a variety of agricultural, industrial, and dietary factors. Conventional therapies cause serious side effects and, at best, merely extend the patient's lifespan by a few years. There is thus the need to utilise alternative concepts or approaches to the prevention of cancer. This review focuses on the many natural products that have been implicated in cancer prevention and that promote human health without recognisable side effects. These molecules originate from vegetables, fruits, plant extracts, and herbs.  相似文献   
47.
A pharmacoscintigraphic study was conducted to compare the dose deposition of HMR 1031 from the existing nebulizer formulation and the new Ultrahaler device to help determine the doses for future phase 2 trials. This was a single-dose, open-label, randomized, two-way crossover study in which HMR 1031 (3 mg) was delivered by the Ultrahaler and the Pari LC Star nebulizer to 12 healthy male subjects. For both treatments, the formulations were radiolabeled with technetium-99m pertechnetate such that a maximum of 10 MBq was delivered on each study day. Scintigraphic images were acquired immediately after dosing to estimate the percentage of the dose delivered to the lungs and oropharynx. Serial plasma samples were collected up to 12 hours post-dose on each occasion and analyzed for HMR 1031 by a LC/MS/MS method with a lower limit of quantitation of 10 pg/mL (0.01 ng/mL). Pharmacokinetic parameters were calculated for HMR 1031 using noncompartmental methods. No serious adverse events were reported. The systemic absorption of HMR 1031 following inhalation administration was relatively rapid, with median T(max) values of 0.5 hours and 1.0 hours post-dose after administration via Ultrahaler and nebulizer, respectively. The mean plasma AUC(0-12) (Ultrahaler, 15.8 ng*h/mL; nebulizer, 11.1 ng*h/mL) and C(max) (Ultrahaler, 4.96 ng/mL; nebulizer, 2.28 ng/mL) values were approximately 42% and 118% higher for the Ultrahaler compared with the nebulizer. The mean terminal half-life of HMR 1031 was similar after administration from both devices (2.91 and 3.18 hours). Based on the scintigraphic data, the lung deposition of HMR 1031 after administration by Ultrahaler (24.6% of the administered dose) was approximately 37% higher compared with the lung deposition from the nebulizer (18.0% of the administered dose). This observation was in agreement with the relative difference in the plasma AUC values achieved after administration of the two formulations. The in vivo results based on the scintigraphic data were also comparable with those from in vitro studies for the Ultrahaler. Based on the ratio of the dose delivered by both the formulations, the required doses for the future Ultrahaler formulation can be predicted.  相似文献   
48.
Objectives To assess the therapeutic efficacy of chloroquine (CQ) treatment against uncomplicated Plasmodium falciparum infections in a tribal population of central India (Madhya Pradesh) and to investigate the prevalence of mutant P. falciparum chloroquine‐resistant transporter (pfcrt) gene in the parasite population. Methods Clinical and parasitological response was determined by in‐vivo testing. For molecular testing, the parasite DNA was extracted from blood samples and used to amplify and sequence parts of the pfcrt (44–177 codons), MSP1 (block 2) and MSP2 (central repeat region) genes. Results Of 463 patients presenting fever, 137 tested positive for P. falciparum. They were treated with CQ. Of these, 58% participated in the study. Overall, treatment failure occurred in 53% of participants. Children under 5 years of age showed significantly more CQ resistance than adults. Mutant genotype S 72 V73M74N75 T 76 was prevalent among both CQ responders (61.29%) and non‐responders (66.7%). Interestingly, several patients from the CQ non‐responder group (33.3%, n = 39) were harbouring parasite with wild type C72V73M74N75K76 genotype of the pfcrt gene. Microsatellite sequences downstream of exon 2 varied widely among both wild type and mutant pfcrt haplotypes. Conclusion The high rate of treatment failure in the present study clearly indicates the need to reassess the use of CQ as first‐line antimalarial therapy in central India. This is supported by the presence of mutant pfcrt genotype among majority of the parasite population of the CQ non‐responder group of patients. However, the presence of wild type amino acid at codon 76 of the pfcrt gene among several patients with CQ non‐responders requires further investigations.  相似文献   
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There exists a wide variation in the competence of the postgraduate residents trained in pathology in different institutions across India. This results in strong disparities in the clinical diagnostic skills, teaching skills, research capabilities and the managerial skills of the graduates. The end users of this training, namely the community, clinicians and health care institutions would benefit from a more uniform and better trained pathologist. The article reviews the reasons for the variation in the quality of the training programs. The main deficiencies include, lack of well-defined criteria for recruitment of residents, training facilities, faculty resources, curriculum with well-defined learning objectives and competencies, hands-on experiences in diagnostic and research activities, diagnostic specimens and medical autopsies, exposure to molecular pathology, pathology informatics, electron microscopy, research experiences, communication skills, professional behavior and bioethics, business practices in pathology and quality assurance. There is also a lack of defined career tracks in various disciplines in laboratory medicine, standard protocols for evaluation and regional and national oversight of the programs. The steps for rectification should include defining the competencies and learning objectives, development of the curriculum including teaching methods, facilities and evaluation strategies, communication skills, professional behavior skills, teaching skills, legal aspects of practicing pathology and the various career pathways to subspecialties in pathology. The training should include defined exposure to molecular pathology, electron microscopy, quality control and assurance, laboratory accreditation, business aspects of pathology practice, review of literature, evidence-based medicine, medical autopsy and medical informatics. Efforts should be made to share human and laboratory resources between regional cooperation. The oversight and accreditation policies should be evolved and well-documented. Web-based platforms need to be developed for easy interaction among residents, faculty and administrators on a national level.  相似文献   
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