A systematic review of the clinical use of Withania somnifera (Ashwagandha) to ameliorate cognitive dysfunction.

Many developed countries are experiencing a rapidly "greying" population, and cognitive decline is common in the elderly. There is no cure for dementia, and pharmacotherapy options to treat cognitive dysfunction provide limited symptomatic improvements. Withania somnifera (Ashwagandha), a popular herb highly valued in Ayurvedic medicine, has often been used to aid memory and cognition. This systematic review thus aimed to evaluate the clinical evidence base and investigate the potential role of W. somnifera in managing cognitive dysfunction. Using the following keywords [withania somnifera OR indian ginseng OR Ashwagandha OR winter cherry] AND [brain OR cognit* OR mental OR dementia OR memory], a comprehensive search of PubMed, EMBASE, Medline, PsycINFO and Clinicaltrials.gov databases found five clinical studies that met the study's eligibility criteria. Overall, there is some early clinical evidence, in the form of randomized, placebo-controlled, double-blind trials, to support the cognitive benefits of W. somnifera supplementation. However, a rather heterogeneous study population was sampled, including older adults with mild cognitive impairment and adults with schizophrenia, schizoaffective disorder, or bipolar disorder. In most instances, W. somnifera extract improved performance on cognitive tasks, executive function, attention, and reaction time. It also appears to be well tolerated, with good adherence and minimal side effects.

A systematic review of the use of rifaximin for Clostridium difficile infections.

Clostridium difficile infection (CDI) is an increasingly common occurrence in the hospital setting, and it is associated with significant morbidity and mortality. In vitro studies have found that rifaximin, a nonabsorbable rifamycin antibiotic, displays potent antimicrobial activity against C. difficile. This systematic review thus aimed to examine the clinical role of rifaximin in CDI. Using the keywords [clostridium OR difficile OR colitis] AND [rifaximin OR xifaxan OR rifagut], a preliminary search on the PubMed, EMBASE, Medline, Clinicaltrials.gov and Google Scholar databases yielded 6210 papers published in English between 1-Jan-1988 and 1-Jul-2018. A total of eight clinical trials were systematically reviewed. Of these, only two were randomized, controlled trials. In the treatment of mild-moderate CDI, rifaximin is a viable alternative to existing therapies (metronidazole or vancomycin). More importantly, rifaximin has a potential role in conjunction with other therapies, showing to be efficacious in reducing the rate of CDI recurrence. However, clinical studies have reported a resistance rate in the range of 29.1-48.9%, with a geographical variance in the distribution of rifaximin-resistant C. difficile strains. With its unique eubiotic properties and positive modulation of the gut flora, rifaximin has a potential therapeutic role in the management of CDI, especially in CDI recurrences. As there is a paucity of randomized, controlled trials to support its use, studies with larger and more diverse populations should be conducted before the efficacy of rifaximin can be conclusively stated. Rifaximin is also a relatively expensive antimicrobial, further studies should include cost-benefit analyses.

Effects of Astaxanthin Supplementation on Skin Health: A Systematic Review of Clinical Studies.

Astaxanthin (AST), a naturally-occurring keto-carotenoid found in several species of bacteria and microalgae, has demonstrated diverse biological activities in vitro and in vivo. There is growing commercial interest in the application of astaxanthin in nutraceuticals and cosmeceuticals, due to its purported photoprotective, DNA repair, antioxidant, and anti-inflammatory benefits. This systematic review therefore aimed to summarize current clinical evidence on the effects of astaxanthin supplementation on skin health. Using the following combinations of broad Major Exploded Subject Headings (MesH) terms or text words [astaxanthin OR AST OR ASX OR carotenoid OR xanthophyll] AND [skin OR derm*], a comprehensive search of PubMed, EMBASE, Medline, Clinicaltrials.gov, and Google Scholar databases found a total of eleven clinical studies. There were six randomized, placebo-controlled, double-blind trials, while the rest were prospective, open-label studies. In many of the randomized, controlled trials reviewed, AST supplementation improved skin texture, appearance (wrinkles), and moisture content at the end of the study period. AST also appeared to protect against UV-induced skin damage. No serious adverse events were reported in any of the studies. However, most available studies had a relatively small sample size and were conducted on healthy Japanese females. Many of the studies were also funded by commercial entities, with potential conflicts of interests. This was difficult to account for in our analyses. Overall, there is some clinical data to support the benefits of astaxanthin supplementation (in the range of 3 to 6 mg/d) on skin health, especially for photoaged skin.

Is there an association between Helicobacter pylori infection and irritable bowel syndrome? A meta-analysis.

BACKGROUND: Irritable bowel syndrome (IBS) is a prevalent and debilitating gastrointestinal condition. Research has reported persistent, low-grade mucosal inflammation and significant overlaps between patients with IBS and those with dyspepsia, suggesting a possible pathogenic role of Helicobacter pylori (H. pylori) in IBS. This study therefore aimed to provide the first systematic review and meta-analysis on the association between H. pylori infection and IBS. AIM: To investigate the association between H. pylori infection and IBS. METHODS: Using the keywords "H. pylori OR Helicobacter OR Helicobacter pylori OR infection" AND "irritable bowel syndrome OR IBS", a preliminary search of PubMed, Medline, Embase, Cochrane Database of Systematic Reviews, Web of Science, Google Scholar and WanFang databases yielded 2924 papers published in English between 1 January 1960 and 1 June 2018. Attempts were also made to search grey literature. RESULTS: A total of 13 clinical studies were systematically reviewed and nine studies were included in the final meta-analysis. Random-effects meta-analysis found a slight increased likelihood of H. pylori infection in patients with IBS, albeit this was not statistically significant (pooled odds ratio 1.47, 95% confidence interval: 0.90-2.40, P = 0.123). It must also be acknowledged that all of the available studies reported only crude odd ratios. H. pylori eradication therapy also does not appear to improve IBS symptoms. Although publication bias was not observed in the funnel plot, there was a high degree of heterogeneity amongst the studies included in the meta-analysis (I 2 = 87.38%). CONCLUSION: Overall, current evidence does not support an association between IBS and H. pylori infection. Further rigorous and detailed studies with larger sample sizes and after H. pylori eradication therapy are warranted.