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41.
This review contains up-to-date knowledge and recent advancements on the essentiality, sources, and toxicological profile of nickel and its different compounds. Nickel is a recognized essential element for several important biological processes like the healthy growth of plants, animals, and soil/water microbes; though an excess amount of nickel intoxicates flora and fauna. Nickel is found to affect the photosynthetic function of higher plants; it can severely degrade soil fertility and causes many chronic diseases in humans. Due to the huge growth in the nickel industry and consumption of nickel-containing products, environmental pollution has become inevitable by the element nickel and also varieties of its by-products through all the phases of making, utilization and dumping. We have focused on the importance of agenda 2030 (UN 17 SDGs) during the preparation of the write-up and have highlighted goals 3, 6, 8, 9, 11, 12, 13, 14, and 15 by elaborately discussing associated points. The plausible molecular mechanism of nickel toxicity is presented in simple diagrams. The article elaborates on possible methods for remediation of nickel toxicity and the treatment of nickel dermatitis and nickel cancer. Recent advancements in the understanding of the dual aspects of nickel as beneficial and a carcinogen are the key subject of this article.

This review contains up-to-date knowledge and recent advancements on the essentiality, sources, and toxicological profile of nickel and its different compounds.  相似文献   
42.
Background and objectivesHumans co-evolved with pathogens, especially helminths, that educate the immune system during development and lower inflammatory responses. The absence of such stimuli in industrialized countries is associated with higher baseline levels of C-reactive protein (CRP) among adults who appear at greater risk for inflammatory disorders. This cross-sectional study examined effects of early life development on salivary CRP levels in 452 British-Bangladeshis who spent varying periods growing up in Bangladesh or UK. We also analyzed how gender and central obesity modulate effects on CRP. We hypothesized that: (i) first-generation Bangladeshis with higher childhood exposure to pathogens would have chronically lower CRP levels than second-generation British-Bangladeshis; (ii) effects would be greater with early childhoods in Bangladesh; (iii) effects by gender would differ; and (iv) increasing obesity would mitigate early life effects.MethodologySaliva samples were assayed for CRP using ELISAs, and anthropometric data collected. Participants completed questionnaires about demographic, socioeconomic, lifestyle and health histories. Data were analyzed using multiple linear regression.ResultsFirst-generation migrants who spent early childhoods in mostly rural, unhygienic areas, and moved to UK after age 8, had lower salivary CRP compared to the second-generation. Effects differed by gender, while waist circumference predicted higher CRP levels. CRP increased with years in UK, alongside growing obesity.Conclusions and implicationsOur study supports the hypothesis that pathogen exposure in early life lowers inflammatory responses in adults. However, protective effects differed by gender and can be eroded by growing obesity across the life course which elevates risks for other inflammatory disorders. Lay Summary: Migrants to the UK who spent early childhoods in less hygienic environments in Bangladesh that help to educate their immune systems had lower levels of the inflammatory marker, C-reactive protein (CRP) compared to migrants who grew up in UK. Both gender and increasing obesity were associated with increased levels of CRP.  相似文献   
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Various attempts have been made to develop artificial conduits for nerve repair, but with limited success. We describe here conduits made from Bombyx mori regenerated silk protein, and containing luminal fibres of Spidrex®, a silk-based biomaterial with properties similar to those of spider silk. Assessment in vitro demonstrated that Spidrex® fibres support neurite outgrowth. For evaluation in vivo, silk conduits 10 mm in length and containing 0, 100, 200 or 300 luminal Spidrex® fibres, were implanted to bridge an 8 mm gap in the rat sciatic nerve. At 4 weeks, conduits containing 200 luminal Spidrex® fibres (PN200) supported 62% and 59% as much axon growth as autologous nerve graft controls at mid-conduit and distal nerve respectively. Furthermore, Spidrex® conduits displayed similar Schwann cell support and macrophage response to controls. At 12 weeks, animals implanted with PN200 conduits showed similar numbers of myelinated axons (81%) to controls, similar gastrocnemius muscle innervation, and similar hindpaw stance assessed by Catwalk footprint analysis. Plantar skin innervation was 73% of that of controls. PN200 Spidrex® conduits were also effective at bridging longer (11 and 13 mm) gaps. Our results show that Spidrex® conduits promote excellent axonal regeneration and function recovery, and may have potential for clinical application.  相似文献   
45.
We report a case of hematometra and bilateral hematosalphinx in a 15-year-old mentally handicapped adolescent girl, complicated by vaginal agenesis over cervical atresia in the presence of an ovarian adenoma. The case was managed by abdominal hysterectomy and bilateral salphingectomy of the hematosalphinx, which had formed a tubo-ovarian mass. One ovary was preserved. This case also considers the management of the mentally handicapped patient unable to comprehend pain arising from cryptomenorrhea.  相似文献   
46.
OBJECTIVES: To investigate the relationship between deprivation, delay and survival from bladder cancer in the West Midlands, as socio-economic deprivation is associated with worse survival in many malignancies, and it has been suggested that treatment differences and delay in seeking care are major contributing causes. PATIENTS AND METHODS: Data were prospectively collected on 1537 newly diagnosed cases of urothelial cancer presenting in the West Midlands between January 1991 and June 1992. Survival was censored at 31 July 2000, when 785 (51%) patients had died. The influence of deprivation on survival was explored using cause-specific and all-cause mortality. RESULTS: Patients in less affluent groups had significantly worse survival than patients in more affluent groups when considering deaths from all causes (P = 0.02), which held true when adjusting for independent prognostic factors (age, smoking history, and tumour grade, stage, type and size). Bladder cancer-specific mortality showed no significant difference between socio-economic groups (P = 0.30). CONCLUSION: Socio-economic deprivation is a significant predictor of survival when death from all causes is considered. However, this does not hold true for bladder cancer-specific death. The perceived differences in treatment and delay between socio-economic groups do not seem to occur for bladder cancer in the West Midlands.  相似文献   
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48.

Objective  

The study was conducted to find out whether there is any significant difference in outcome if low birth weight babies weighing between 1500g and 1800g are managed by keeping them with their mothers, i.e., without special care neonatal unit (SCNU) admission.  相似文献   
49.
PURPOSE: Squamous cell carcinomas of the head and neck (HNSCC) often harbor p53 mutations, but p53 protein degradation by the viral oncoprotein E6 may supercede p53 mutations in human papillomavirus 16 (HPV16)-positive tumors. The prevalence of p53 mutations in HPV-positive HNSCCs is indeed lower, but in some tumors these alterations coexist. The purpose of this study was to discern whether HNSCCs differ in the type of p53 mutations as a function of HPV16 status. EXPERIMENTAL DESIGN: The study was nested within a prospective multicenter study (ECOGE 4393/RTOG R9614) of patients with HNSCC treated surgically with curative intent. Tumors from one study center were used to construct a tissue microarray. The tumors were well characterized with respect to p53 mutational status. The tissue microarray was evaluated by HPV16 in situ hybridization. HPV16 analysis was also done on a select group of tonsillar carcinomas known to harbor disruptive p53 mutations defined as stop mutations or nonconservative mutations within the DNA binding domain. RESULTS: HPV16 was detected in 12 of 89 (13%) HNSCCs. By tumor site, HPV16 was detected in 12 of 21 (57%) tumors from the palatine/lingual tonsils, but in none of 68 tumors from nontonsillar sites (P < 0.00001). Both HPV16-positive and HPV16-negative HNSCCs harbored p53 mutations (25% versus 52%), but disruptive mutations were only encountered in HPV16-negative carcinomas. Of seven tonsillar carcinomas with disruptive p53 mutations, none were HPV16 positive, in contrast to HPV16-positive tonsillar carcinomas without disruptive p53 mutations (0% versus 57%; P = 0.008). CONCLUSIONS: Although HPV16 and mutated p53 may coexist in a subset of HNSCCs, HPV16 and disruptive p53 mutations seem to be nonoverlapping events. A less calamitous genetic profile, including the absence of disruptive p53 mutations, may underlie the emerging clinical profile of HPV16-positive HNSCC such as improved patient outcome.  相似文献   
50.
PURPOSE: Patients with head and neck squamous cell carcinoma (HNSCC) often clinically present with metastases to regional lymph nodes. Fine-needle aspiration of neck masses is routinely used to establish the presence of metastatic carcinoma and in turn to initiate a subsequent workup to determine the site of tumor origin. Human papillomavirus (HPV) 16 is an important etiologic agent for HNSCCs that arise from the oropharynx but less so for tumors from non-oropharyngeal sites. HPV16 detection thus provides a strategy for localizing an important subset of HNSCCs, but this approach has not been applied to fine-needle aspiration specimens. EXPERIMENTAL DESIGN: We did in situ hybridization for HPV16 on 77 consecutive aspirated neck masses diagnosed as metastatic squamous cell carcinoma. P16 immunohistochemistry was also done because p16 overexpression may serve as a surrogate marker of HPV-associated HNSCC. RESULTS: HPV16 was detected in 13 of the 77 (17%) aspirates. By site of origin, HPV16 was detected in 10 of 19 metastases from the oropharynx but in none of 46 metastases from other sites (53% versus 0%; P < 0.0001). HPV16 was not detected in 2 branchial cleft cysts misdiagnosed as metastatic squamous cell carcinoma, but it was detected in 3 of 10 metastases from occult primary tumors. P16 expression was associated with the presence of HPV16: 12 of 13 HPV16-positive metastases exhibited p16 expression, whereas only 4 of 62 HPV16-negative metastases were p16 positive (92% versus 6%; P < 0.0001). P16 expression also correlated with site of tumor origin: 13 of 19 oropharyngeal metastases were p16 positive, whereas only 1 of 46 non-oropharyngeal metastases was p16 positive (68% versus 2%; P < 0.0001). CONCLUSIONS: HPV16 status can be determined in tumor cells aspirated from the necks of patients with metastatic HNSCC. Its presence is a reliable indicator of origin from the oropharynx.  相似文献   
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