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Clinical Rheumatology - Takayasu arteritis (TAK) is a less common large-vessel vasculitis which can occur in either children or adults. However, differences between pediatric-onset and adult-onset...  相似文献   
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BackgroundCampylobacter spp. are one of the commonest causes of diarrhea in children under five and in resource poor settings also lead to malabsorption and stunting. The purpose of this systematic review was to understand the burden of Campylobacter spp. associated diarrhea among children in the South Asian countries.MethodsThis systematic review followed the PRISMA (Preferred Reporting Items for Systematic reviews and Meta-Analysis) guidelines. Databases were searched with defined keywords for publications from the years 1998–2018. Data on proportion of positive samples was extracted to compare the rates of Campylobacter infection among children (under the age of 19) from different study populations.ResultsOf the 359 publications screened, 27 eligible articles were included in this systematic review and categorized based on study design. In 8 case-control studies, Campylobacter spp. was detected more frequently among diarrheal cases (range, 3.2–17.4%) than non-diarrheal cases (0–13%). Although there were variations in the study population, overall, children under the age of two years experienced Campylobacter diarrhea more often than older children. Most studies reported stool culture as the method used to detect Campylobacter spp. however retesting using PCR-based methods significantly increased detection rates. Limited data were available on Campylobacter species. In 4 studies that provided species data, C. jejuni (3.2–11.2%) was shown to be the most common species, followed by C. coli.ConclusionIn South Asia, Campylobacter spp. are one of the most common bacterial diarrheal pathogens affecting children but there is a paucity of data on species, risk factors and attributable sources. Although a few studies were available, the epidemiology of campylobacteriosis remains uncertain. To understand the true burden and sources of infection, more detailed studies are needed collecting data from human, animal and environmental sources and using both culture and genomic tools.  相似文献   
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Introduction

Numerous antimicrobial agents are used to eliminate oral biofilm. However due to emergence of multi drug resistant microorganisms, the quest to find out biologically safe and naturally available antimicrobial agents continues.

Aim

To evaluate antimicrobial efficacy of silver nano-particles against five common oral pathogenic bacteria.

Objective

To determine antimicrobial activity of silver nanoparticles and chlorhexidine gluconate against oral pathogenic bacteria.

Material and Method

We used strains of Streptococcus mutans (MTCC 497), Streptococcus oralis (MTCC 2696), Lactobacillus acidophilus (MTCC 10307), Lactobacillus fermentum (MTCC 903), and Candida albicans (MTCC 183). We used commercially available silver nanoparticles (experimental group) and chlorhexidine gluconate (positive control). We determined minimum inhibitory concentration (MIC) minimum bactericidal concentration (MBC) of both agents and analyzed the data using paired ‘t’ test, one way ANOVA and Tucky’s post Hoc HSD.

Result

Silver nanoparticles inhibited bacterial growth moderately. The mean MIC of AgNP against S. mutans was 60?±?22.36?μg/ml, S. oralis – 45?±?11.18?μg/ml, L. acidophilus – 15?±?5.59?μg/ml, L. fermentum – 90?±?22.36?μg/ml, Candida albicans – 2.82?±?0.68?μg/ml respectively. For chlorhexidine gluconate, mean MIC for S. mutans was 300?±?111.80?μg/ml, S. oralis – 150?±?55.90?μg/ml, L. acidophilus – 450?±?111.80?μg/ml, L. fermentum – 450?±?111.80?μg/ml and Candida albicans – 150?±?55.90?μg/ml. MIC and MBC values of AgNP were significantly lower than chlorhexidine gluconate and statistically significant (p?<?0.05).

Conclusion

Silver nanoparticles exhibited better bacteriostatic and bactericidal effect with concentration less than five folds as compared to chlorhexidine. Silver nanoparticles when used in appropriate concentration as safe alternative to present chemically derived other antimicrobial agents.  相似文献   
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In contrast to the conventional radiotherapy/chemoradiotherapy paradigms used in the treatment of majority of cancer types, this review will describe two areas of radiobiology, hyperfractionated and hypofractionated radiation therapy, for cancer treatment focusing on application of novel concepts underlying these treatment modalities. The initial part of the review discusses the phenomenon of hyper-radiation sensitivity (HRS) at lower doses (0.1 to 0.6 Gy), describing the underlying mechanisms and how this could enhance the effects of chemotherapy, particularly, in hyperfractionated settings. The second part examines the radiobiological/physiological mechanisms underlying the effects of high-dose hypofractionated radiation therapy that can be exploited for tumor cure. These include abscopal/bystander effects, activation of immune system, endothelial cell death and effect of hypoxia with re-oxygenation. These biological properties along with targeted dose delivery and distribution to reduce normal tissue toxicity may make high-dose hypofractionation more effective than conventional radiation therapy for treatment of advanced cancers. The novel radiation physics based methods that take into consideration the tumor volume to be irradiated and normal tissue avoidance/tolerance can further improve treatment outcome and post-treatment quality of life. In conclusion, there is enough evidence to further explore novel avenues to exploit biological mechanisms from hyper-fractionation by enhancing the efficacy of chemotherapy and hypo-fractionated radiation therapy that could enhance tumor control and use imaging and technological advances to reduce toxicity.KEYWORDS : Low Doses Fractionated Radiation Therapy (LDFRT), hyper-radiation sensitivity (HRS), induced radiation resistance (IRR), hyperfractionation, chemopotentiation, stereotactic body radiation therapy (SBRT), stereotactic ablative radiosurgery (SARS), stereotactic ablative radiotherapy (SABR), stereotactic radiosurgery (SRS), spatially fractionated GRID radiotherapy (SFGRT), lattice  相似文献   
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