Garlic for hypertension: A systematic review and meta-analysis of randomized controlled trials

BackgroundIn the past decade, garlic has become one of the most popular complementary therapies for blood pressure (BP) control used by hypertensive patients. Numerous clinical studies have focused on the BP-lowering effect of garlic, but results have been inconsistent. Overall, there is a dearth of information available to guide the clinical community on the efficacy of garlic in hypertensive patients.AimTo systematically review the medical literature to investigate the current evidence of garlic for the treatment of hypertension.MethodsPubMed, the Cochrane Library and EMBASE were searched for appropriate articles from their respective inceptions until August 2014. Randomized, placebo-controlled trials comparing garlic vs. a placebo in patients with hypertension were considered. Papers were independently reviewed by two reviewers and were analyzed using Cochrane software Revman 5.2.ResultsA total of seven randomized, placebo-controlled trials were identified. Compared with the placebo, this meta-analysis revealed a significant lowering effect of garlic on both systolic BP (WMD: −6.71 mmHg; 95% CI: −12.44 to −0.99; P = 0.02) and diastolic BP (WMD: −4.79 mmHg; 95% CI: −6.60 to −2.99; P < 0.00001). No serious adverse events were reported in any of the trials.ConclusionThe present review suggests that garlic is an effective and safe approach for hypertension. However, more rigorously designed randomized controlled trials focusing on primary endpoints with long-term follow-up are still warranted before garlic can be recommended to treat hypertensive patients.     

Vitamin A and retinoid derivatives for lung cancer: a systematic review and meta analysis

Background

Despite reported antiproliferative activity of vitamin A and its common use for cancer, there is no comprehensive synthesis of its safety and efficacy in lung cancers. To address this issue we conducted a systematic review of the safety and efficacy of vitamin A for the treatment and prevention of lung cancers.

Methods and Findings

Two independent reviewers searched six electronic databases from inception to July 2009 for clinical, observational, and preclinical evidence pertaining to the safety and efficacy of vitamin A and related retinoids for lung cancers. 248 studies were included for full review and analysis. Five RCTs assessed treatment of lung cancers, three assessed primary prevention, and three looked at secondary prevention of lung cancers. Five surrogate studies, 26 phase I/II, 32 observational, and 67 preclinical studies were also included. 107 studies were included for interactions between vitamin A and chemo- or radiation- therapy. Although some studies demonstrated benefits, there was insufficient evidence overall to support the use of vitamin A or related retinoids for the treatment or prevention of lung cancers. Retinyl palmitate combined with beta carotene increased risk of lung cancer in smokers in the large CARET trial. Pooling of three studies pertaining to treatment and three studies on secondary prevention revealed no significant effects on response rate, second primary tumor, recurrence, 5-year survival, and mortality. There was a small improvement in event free survival associated with vitamin A compared to controls, RR 1.24 (95% CI 1.13–1.35). The synthetic rexinoid bexarotene increased survival significantly among a subset of patients in two RCTs (p<0.014, <0.087).

Conclusions

There is a lack of evidence to support the use of naturally occuring retinoids for the treatment and prevention of lung cancers. The rexinoid bexarotene may hold promise for use among a subset of patients, and deserves further study.     

Effect of maternal zinc deficiency on offspring health: The epigenetic impact

BackgroundZinc deficiency is associated with adverse effects on maternal health and pregnancy outcomes. These consequences have been reported over the years from zinc supplementation trials and observational studies whereby outcomes of maternal, foetal and infant health were measured. Owing to the importance of zinc in the functions of epigenetic enzymes, pre-clinical studies have shown that its deficiency could disrupt biological activities that involve epigenetic mechanisms in offspring. Thus, this review assessed the link between epigenetics and the effects of maternal zinc deficiency on the offspring’s health in animal studies.MethodsResearch articles were retrieved without date restriction from PubMed, Web of Science, ScienceDirect, and Google Scholar databases, as well as reference lists of relevant articles. The search terms used were “zinc deficiency”, “maternal zinc deficiency”, “epigenetics”, and “offspring.” Six studies met the eligibility criteria and were reviewed.ResultsAll the eligible studies reported maternal zinc deficiency and observed changes in epigenetic markers on the progeny during prenatal and postnatal stages of development. The main epigenetic markers reported were global and gene specific methylation and/ or acetylation. The epigenetic changes led to mortality, disruption in development, and risk of later life diseases.ConclusionMaternal zinc deficiency is associated with epigenetic modifications in offspring, which induce pathologies and increase the risk of later life diseases. More research and insight into the epigenetic mechanisms could spring up new approaches to combat the associated disease conditions.     

Effect of mesenchymal stromal cell transplantation on long-term survival in amyotrophic lateral sclerosis

Background aimsThanks to their immunomodulatory, tissue-protective and regenerative properties, mesenchymal stromal cells (MSCs) are a promising approach for amyotrophic lateral sclerosis (ALS); however, trials are limited and few follow-up studies have been published. This post-hoc analysis aims to describe the potential long-term effects of MSCs in ALS, analyzing data from two phase 1 clinical trials in ALS patients conducted by our group in 2002 and 2006.MethodsWe conducted two consecutive phase 1 prospective, open, pilot clinical trials, enrolling a total of 19 ALS patients. We followed patients for the duration of the disease. For each patient, we used the European Network to Cure ALS (ENCALS) survival prediction model to retrospectively calculate the expected survival at diagnosis. We then compared the predicted disease duration with the observed survival, analyzing patients at a single-patient level.ResultsUsing the ENCALS model, we predicted short survival in one patient, intermediate survival in three patients, long survival in three patients and very long survival in 12 patients. The difference between predicted and observed survival for the whole group was significant and demonstrated a mean predicted survival of 70.79 months (standard deviation [SD], 27.53) and a mean observed survival of 118.8 months (SD, 89.26) (P = 0.016). Based on the monthly ALS Functional Rating Scale–Revised progression rate (median, 0.64/month), we considered 10 of 19 patients slow progressors and nine of 19 patients fast progressors. Of the slow progressors, eight of 10 (80%) had significantly increased disease duration compared with predicted, and only two (20%) had decreased estimated disease duration. By contrast, five of nine (55%) fast progressors had increased disease duration, whereas four (45%) had decreased disease duration. To date, four patients are still alive.ConclusionsThe current study represents the first very long-term analysis of survival as an effect of MSC focal transplantation in the central nervous system of ALS patients, demonstrating that MSC transplantation could potentially slow down ALS progression and improve survival. Due to the interindividual variability in clinical course, at the current state of our knowledge, we cannot generalize the results, but these data provide new insights for planning the next generation of efficacy MSC clinical trials in ALS.     

Roles of traditional medicine and traditional healers for rabies prevention and potential impacts on post-exposure prophylaxis: A literature review

IntroductionGlobally, traditional medicine is widely used to treat a variety of injuries and illnesses, including dog bites, and exposures that are risky for rabies. However, efficacy of most traditional remedies used for rabies prevention or treatment has not been demonstrated in controlled trials or proven in community-based surveys.MethodsSix databases were searched including the terms rabies, traditional treatment, traditional remedy, traditional therapy, traditional medicine, and medicinal treatment to review traditional remedies used in the prevention and treatment of rabies. In addition, published literature of rabies transmission dynamics was used to estimate statistical likelihood of dog bite victims developing rabies to provide clarity as to why traditional healers have a high apparent success rate when preventing death from rabies in victims bitten by suspected rabid dogs.ResultsLiterature review yielded 50 articles, including three controlled experiments, that described use of traditional remedies for rabies prevention and treatment. Traditional remedies for rabies ranged from plant- or animal-based products to spiritual rituals; however, only a few controlled mice trials were conducted, and none of these trials demonstrated efficacy in preventing or treating rabies. Risk of dying from rabies after a bite from a dog with unknown rabies status is low, 1.90% (0.05%-29.60%). Therefore, traditional healers had a 98.10% (70.40%-99.95%) apparent success rate in preventing death from suspected rabid dog bites despite inefficaciousness of herbal remedies.ConclusionThere was no universal plant species or route of administration that was consistently used for rabies prevention or treatment across countries. No traditional remedy was efficacious in the prevention or treatment of rabies in randomized controlled experiments. Understanding the cultural context under which traditional remedies are used may facilitate collaboration of traditional healers with the modern medical system to ensure timely and appropriate use of proven therapies for prevention and clinical management of rabies.     

Clinical outcomes and outcome measurement tools reported in randomised controlled trials of treatment for snakebite envenoming: A systematic review

BackgroundSnakebite is a priority neglected tropical disease and causes a range of complications that vary depending on the snake species. Randomised clinical trials have used varied outcome measures that do not allow results to be compared or combined. In accordance with the Core Outcomes Measurements in Effectiveness Trials (COMET) initiative, this systematic review aims to support the development of a globally relevant core outcome set for snakebite.MethodsAll randomised controlled trials, secondary analyses of randomised controlled trials and study protocols investigating the efficacy of therapeutics for human snakebite envenoming were eligible for inclusion. Study screening and data extraction were conducted in duplicate by two independent reviewers. All primary and secondary outcome measures were extracted and compiled, as were adverse event outcome measures. Similar outcome measures were grouped into domains. The study was prospectively registered with PROSPERO: CRD42020196160.ResultsThis systematic review included 43 randomised controlled trials, two secondary analyses and 13 study protocols. A total of 382 outcome measures were extracted and, after duplicates were merged, there were 153 unique outcomes. The most frequently used outcome domain (‘venom antigenaemia’) was included in less than one third of the studies. The unique outcomes were classified into 60 outcome domains. Patient-centred outcomes were used in only three of the studies.DiscussionSignificant heterogeneity in outcome measures exists in snakebite clinical trials. Consensus is needed to select outcome measures that are valid, reliable, patient-centred and feasible. The results of this systematic review strongly support the development of a core outcome set for use in snakebite clinical trials.     

Fibrin Sealants in Dura Sealing: A Systematic Literature Review

BackgroundFibrin sealants are widely used in neurosurgery to seal the suture line, provide watertight closure, and prevent cerebrospinal fluid leaks. The aim of this systematic review is to summarize the current efficacy and safety literature of fibrin sealants in dura sealing and the prevention/treatment of cerebrospinal fluid leaks.MethodsA comprehensive electronic literature search was run in the following databases: Cochrane Database of Systematic Reviews, Cochrane Central Resister of Controlled Trials, clinicaltrials.gov, MEDLINE/PubMed, and EMBASE. Titles and abstracts of potential articles of interest were reviewed independently by 3 of the authors.ResultsA total of 1006 database records and additional records were identified. After screening for duplicates and relevance, a total of 78 articles were assessed by the investigators for eligibility. Thirty-eight were excluded and the full-text of 40 articles were included in the qualitative synthesis. Seven of these included only safety data and were included in the safety assessment. The remaining 33 articles included findings from 32 studies that enrolled a total of 2935 patients who were exposed to fibrin sealant. Among these 33 studies there were only 3 randomized controlled trials, with the remaining being prospective cohort analysis, case controlled studies, prospective or retrospective case series. One randomized controlled trial, with 89 patients exposed to fibrin sealant, found a greater rate of intraoperative watertight dura closure in the fibrin sealant group than the control group (92.1% versus 38.0%, p<0.001); however, post-operative cerebrospinal fluid leakage occurred in more fibrin sealant than control patients (6.7% versus 2.0%, p>0.05). Other clinical trials evaluated the effect of fibrin sealant in the postoperative prevention of cerebrospinal fluid leaks. These were generally lower level evidence studies (ie, not prospective, randomized, controlled trials) that were not designed or powered to demonstrate a significant advantage to fibrin sealant use. Two small case series studies evaluated the effect of fibrin sealants in persistent cerebrospinal fluid leak treatment, but did not establish firm efficacy conclusions. Specific adverse reports where fibrin sealants were used for dura sealing were limited, with only 8 cases reported in neurosurgical procedures since 1987 and most reporting only a speculative relationship/association with fibrin sealant exposure.ConclusionsA major finding of this systematic literature review is that there is a paucity of randomized studies that have evaluated the effectiveness and safety of fibrin sealants in providing intraoperative watertight dura closure and post-operative cerebrospinal fluid leakage. Among the limited studies available, evidence from a single randomized, controlled trial indicates that fibrin sealants provide a higher rate of intraoperative watertight closure of the dura suture line than control, albeit with a higher rate of postoperative cerebrospinal fluid leakage. Evidence from non-randomized, controlled trials suggests that fibrin sealants may be effective in preventing cerebrospinal fluid leaks with an acceptable safety profile. There is a substantial need for randomized, controlled clinical trials or well-designed prospective observational trials where the conduct of a randomized trial is not feasible to fully assess the impact of fibrin sealant utilization on the rates of intraoperative dura closure, postoperative cerebrospinal leakage, and safety.     

Peripheral blood-derived autologous stem cell therapy for the treatment of patients with late-stage peripheral artery disease—results of the short- and long-term follow-up

Background aimsRegeneration of the occluded peripheral arteries by autologous stem cell therapy is an emerging treatment modality for no-option patients with peripheral artery disease (PAD). The purpose of this study was to assess safety and efficacy of in vitro–expanded, peripheral blood-derived, autologous stem cells (VesCell) in no-option patients with PAD.MethodsA phase II, open-label, randomized clinical study was performed on 20 patients to investigate the safety and efficacy of VesCell therapy at 1 and 3 months of follow-up. The long-term (2 years) efficacy of the therapy was also evaluated.ResultsNo side effects of VesCell therapy were found. During the 3 month follow-up in the control group, one death occurred and six major amputations were performed; in the treated group, there were no deaths or major amputations. The difference of limb loss is significant between the two groups. At 2-year follow-up in the control group, two deaths and six major amputations occurred; in the treated group, there were three major amputations. At 3-month follow-up, the change in hemodynamic parameters showed a significant increase in the treated group over the control group; in the treated group, further improvement was detected at 2 years. As the result of the VesCell treatment, change in pain score, wound healing and walking ability test showed an improvement compared with the control group; at 2 years, incremental improvement was observed.ConclusionsPeripheral blood-derived, in vitro–expanded autologous angiogenic precursor therapy appears to be a safe, promising and effective adjuvant therapy for PAD patients.     

Continuous Subcutaneous Infusion of Insulin Lispro in Children and Adolescents with Type 1 Diabetes Mellitus

ObjectiveTo provide a comprehensive review of insulin lispro administered by continuous subcutaneous insulin infusion (CSII) in children and adolescents.MethodsWe performed PubMed literature searches to identify clinical studies of insulin lispro administered via CSII within pediatric and adolescent populations.ResultsTwenty-six studies involving 2521 pediatric patients with type 1 diabetes mellitus met inclusion criteria. Of these, 10 were randomized controlled trials (RCTs), 6 of which compared insulin lispro CSII with multiple daily injection (MDI) therapy. We identified 7 additional prospective, nonrandomized studies and 9 retrospective studies. Within the RCTs, endpoint hemoglobin A_1c levels ranged from 6.3% to 8.5% for insulin lispro CSII therapy and from 6.2% to 8.7% for those trials with MDI comparator arms. In those trials that compared insulin lispro CSII with MDI, the endpoint hemoglobin A_1c achieved with insulin lispro was similar or improved compared with observations in the MDI treatment arm. In the RCTs, severe hypoglycemia rates of 0.1 to 0.3 episodes/patient per year were reported for insulin lispro CSII therapy; those trials with MDI comparator arms reported relatively similar severe hypoglycemia rates (0.1 to 0.5 episodes/patient per year). Events of diabetic ketoacidosis (DKA) were rare. Where reported, insulin lispro CSII and MDI therapy demonstrated a similar occurrence of DKA and incidence of severe hypoglycemia. Prospective and retrospective studies demonstrated results similar to the RCT findings.ConclusionsIn 26 studies of more than 2500 pediatric and adolescent patients with type 1 diabetes, with more than 1000 patients specifically receiving insulin lispro CSII, insulin lispro CSII therapy consistently demonstrated similar or improved efficacy and safety vs studied comparators. (Endocr Pract. 2012;18:418-424)     

Cardiovascular risk factor reporting in immune checkpoint inhibitor trials: A systematic review

BackgroundImmune checkpoint inhibitors (ICI) have revolutionized the treatment of numerous cancers but are associated with increased risk of myocardial infarction. The prevalence of traditional cardiovascular risk factors (CVRF) in patients treated with ICIs is unknown. This study sought to describe the frequency of reporting of CVRFs among landmark ICI trials.MethodsA systematic review of all phase 2 or 3 cancer trials employing ICIs that led to United States Food and Drug Administration approval was conducted.ResultsOf the 69 identified trials, only one study reported baseline rates of hypertension, diabetes mellitus, and dyslipidemia. Smoking history was reported in 27 studies (39 %) and three (4 %) reported body mass index. No study reported history of previous cardiovascular disease, although 17 (25 %), six (9 %), and 21 (30 %) studies excluded patients with recent myocardial infarction, revascularization and heart failure respectively. Similarly low rates of cardiovascular risk factor reporting were observed in studies employing concurrent vascular endothelial growth factor inhibitors and recruiting (neo)adjuvant cohorts.ConclusionThe prevalence of CVRFs is poorly described in ICI trials despite increasingly reported risks of myocardial infarction. A systematic approach to collecting and reporting CVRFs should be considered in future trials and real world populations.     

The effect of zinc supplementation on brain derived neurotrophic factor: A meta-analysis

BackgroundZinc in one of the most abundant trace minerals in human body which is involved in numerous biological pathways and has variety of roles in the nervous system. It has been assumed that zinc exerts its role in nervous system through increasing brain derived neurotrophic factor (BDNF) concentrations.ObjectivesPresent meta-analysis was aimed to review the effect of zinc supplementation on serum concentrations of BDNF.Methods and materialsFour electronic databases (Pubmed, Scopus, Web of Science, Embase) were searched for identifying studies that examined BDNF levels prior and after zinc supplementation up to May 2020. According to the Cochrane guideline, a meta-analysis was performed to pool the effect size estimate (Hedges’ test) of serum BDNF across studies. Risk of publication bias was assessed using a funnel plot and Egger’s test.ResultsFive studies were eligible and 238 participants were included. These studies enrolled subjects with premenstrual syndrome, diabetic retinopathy, major depression disorder, overweight/obese and obese with mild to moderate depressive disorders. Zinc supplementation failed to increase blood BDNF concentrations with effect size of 0.30 (95 % CI: -0.08, 0.67, P = 0.119). Funnel plot did not suggest publication bias.ConclusionZinc supplementation may not significantly increase BDNF levels. However, the small number of included articles and significant heterogeneity between them can increase the risk of a false negative result; therefore, the results should be interpreted with caution.     

Vitamin D for Treatment and Prevention of Infectious Diseases; A Systematic Review of Randomized Controlled Trials

ObjectiveTo review the existing human controlled intervention studies of vitamin D as adjunctive therapy in settings of infection and provide recommendations for design and implementation of future studies in this field on the basis of the evidence reviewed.MethodsWe conducted a systematic review of randomized controlled clinical trials that studied vitamin D for treatment or prevention of infectious diseases in humans. Studies from 1948 through 2009 were identified through search terms in PubMed and Ovid MEDLINE.ResultsThirteen published controlled trials were identified by our search criteria. Ten trials were placebo controlled, and 9 of the 10 were conducted in a rigorous double-blind design. The selected clinical trials demonstrated substantial heterogeneity in baseline patient demographics, sample size, and vitamin D intervention strategies. Serious adverse events attributable to vitamin D supplementation were rare across all studies. On the basis of studies reviewed to date, the strongest evidence supports further research into adjunctive vitamin D therapy for tuberculosis, influenza, and viral upper respiratory tract illnesses. In the selected studies, certain aspects of study design are highlighted to help guide future clinical research in the field.ConclusionMore rigorously designed clinical trials are needed for further evaluation of the relationship between vitamin D status and the immune response to infection as well as for delineation of necessary changes in clinical practice and medical care of patients with vitamin D deficiency in infectious disease settings. (Endocr Pract. 2009;15:438-449)     

阿魏酸钠联合双黄连注射液对病毒性心肌炎患者临床疗效及血清基质金属蛋白酶、锌铜水平的影响

目的:探究阿魏酸钠联合双黄连注射液对病毒性心肌炎患者临床疗效及血清基质金属蛋白酶、锌铜水平的影响。方法:选择在我院确诊为病毒性心肌炎的患者39例,随机分成实验组以及对照组。对照组18例给予阿魏酸钠治疗;实验组21例予阿魏酸钠联合双黄连注射液治疗。治疗14天后,评价和比较两组患者的临床疗效、心肌酶谱水平、血清基质金属蛋白酶水平及血清锌铜比值。结果:实验组总有效率为95.2%,显著高于对照组(72.2%),差异具统计学意义(P0.05)。与对照组比,实验组治疗后的血清、乳酸脱氢酶(LDH)水平、肌酸磷酸激酶同工酶(CK-MB)、天冬氨酸氨基转移酶(AST)、基质金属蛋白酶水平较低,血清铜锌比值较小,而左室射血分数(LVEF)水平较高,差异均具有统计学意义(P0.05)。结论:阿魏酸钠联合双黄连注射液治疗病毒性心肌炎患者能够有效提高其临床疗效,可能与其显著降低血清基质金属蛋白酶及铜锌水平有关。     

Echinacea in hepatopathy: A review of its phytochemistry,pharmacology, and safety

BackgroundEchinacea, one of the most popular herbs with double function of immunity and anti-inflammatory activity, has now attracted much interest for a possible alternative for the treatment of hepatopathy. This review is aimed at providing a comprehensive overview of Echinacea regarding its chemical composition, pharmacological action against various hepatopathy, and safety.MethodsA comprehensive search of published articles was conducted to focus on original publications related to Echinacea and hepatopathy till the end of 2020 using various literature databases, including China National Knowledge Infrastructure, PubMed, and Web of Science database.ResultsEchinacea exhibited excellent activities in resisting a variety of hepatopathy induced by different causes in preclinical experiments and clinical trials by regulating cell proliferation and apoptosis, antioxidant defense mechanism, voltage-gated sodium channels, lipid metabolism, circadian rhythm, p38 MAPK signaling pathway, JNK signaling pathway, Nrf2/HO-1 signaling pathway, PI3K/AKT signaling pathway, and Akt/GSK3 beta signaling pathways. The high efficacy of Echinacea is related to its immunomodulatory and anti-inflammatory activities. The main ingredients of Echinacea include caffeic acid derivatives, alkylamides, and polysaccharides, which have been well established in preclinical studies of liver diseases. Studies on acute and subacute toxicity show that Echinacea preparations are well-tolerated herbal medicines.ConclusionEchinacea may offer a novel potential strategy for clinical prevention and treatment of liver diseases and related diseases. Extensive studies are necessary to identify the underlying mechanisms and establish future therapeutic potentials of this herb. Well-designed clinical trials are still warranted to confirm the safety and effectiveness of Echinacea for hepatopathy.     

Efficacy and safety of atrial fibrillation ablation in heart failure patients with left ventricular ejection fraction less than 50%

IntroductionThe efficacy of catheter ablation in patients with low cardiac function has been previously reported; however, only a few studies have included mid-range ejection fraction (mrEF). This study aimed to evaluate the efficacy and safety of atrial fibrillation (AF) ablation in patients with left ventricular ejection fraction (LVEF) < 50%.MethodsThis study retrospectively analyzed 79 patients (reduced ejection fraction [rEF]/mrEF, 38/41; paroxysmal/persistent, 37/42; heart failure hospitalizations within one year before ablation, 36 [45.6%]) who underwent the first ablation procedure at our hospital from April 2017 to December 2021. Radiofrequency ablation and cryoablation were performed for 69 and 10 patients, respectively.ResultsComplications included pacemaker implantation for postoperative sick sinus syndrome in one patient and inguinal hematoma in one patient. Regarding efficacy, there were significant postoperative improvements in echocardiographic data, blood test values, and diuretic use. After a mean follow-up of 60 months, 86.1% patients had no AF recurrence. There were 9 heart failure hospitalizations (11.4%) and 5 all-cause deaths (6.3%); no significant differences were found between the rEF and mrEF groups. No significant predictors of AF recurrence were found in preoperative patient characteristics.ConclusionAF ablation in patients with LVEF <50% significantly improved cardiac and renal functions with few complications, resulting in a high non-recurrence rate and reduced heart failure.     

Clinical trials of antioxidants as cancer prevention agents: past, present, and future

The purpose of this review is to summarize the most important human clinical trials of antioxidants as cancer prevention agents conducted to date, provide an overview of currently ongoing studies, and discuss future steps needed to advance research in this field. To date there have been several large (at least 7000 participants) trials testing the efficacy of antioxidant supplements in preventing cancer. The specific agents (diet-derived direct antioxidants and essential components of antioxidant enzymes) tested in those trials included β-carotene, vitamin E, vitamin C, selenium, retinol, zinc, riboflavin, and molybdenum. None of the completed trials produced convincing evidence to justify the use of traditional antioxidant-related vitamins or minerals for cancer prevention. Our search of ongoing trials identified six projects at various stages of completion. Five of those six trials use selenium as the intervention of interest delivered either alone or in combination with other agents. The lack of success to date can be explained by a variety of factors that need to be considered in the next generation research. These factors include lack of good biological rationale for selecting specific agents of interest; limited number of agents tested to date; use of pharmacological, rather than dietary, doses; and insufficient duration of intervention and follow-up. The latter consideration underscores the need for alternative endpoints that are associated with increased risk of neoplasia (i.e., biomarkers of risk), but are detectable prior to tumor occurrence. Although dietary antioxidants are a large and diverse group of compounds, only a small proportion of candidate agents have been tested. In summary, the strategy of focusing on large high-budget studies using cancer incidence as the endpoint and testing a relatively limited number of antioxidant agents has been largely unsuccessful. This lack of success in previous trials should not preclude us from seeking novel ways of preventing cancer by modulating oxidative balance. On the contrary, the well demonstrated mechanistic link between excessive oxidative stress and carcinogenesis underscores the need for new studies. It appears that future large-scale projects should be preceded by smaller, shorter, less expensive biomarker-based studies that can serve as a link from mechanistic and observational research to human cancer prevention trials. These relatively inexpensive studies would provide human experimental evidence for the likely efficacy, optimum dose, and long-term safety of the intervention of interest that would then guide the design of safe, more definitive large-scale trials.     

Association between toenail zinc concentrations and incidence of asthma among American young adults: The CARDIA study

BackgroundAs an essential micronutrient, zinc plays an important role in modulating the immune system. However, data on the association between zinc concentrations and asthma incidence are sparse, especially in adults.MethodsWe prospectively followed up 3682 individuals aged 20–32 years without history of asthma or current asthma at baseline from 1987–1988 to 2015–2016. Zinc concentrations were measured in toenail clippings collected at Exam Year 2 using inductively-coupled-plasma mass spectroscopy. Asthma was diagnosed by a physician and/or reported medication use for asthma control with verification. Cox regression was used to model the association between toenail zinc concentrations and asthma incidence.ResultsOver an average of 22.5 years of follow-up, 508 incident cases of asthma were identified. After adjustment for potential confounders, no statistically significant association was found between zinc concentration and asthma incidence (HR = 0.81; 95% CI: 0.62, 1.07; P_{linear trend} = 0.26). The observed association was not materially modified by sex, body mass index, smoking or atopic status. When stratifying data by race, a significant inverse linear association was found among African Americans (per 1 standard deviation increment in toenail zinc concentrations: HR = 0.86; 95% CI: 0.75, 0.99; P_{linear trend} = 0.03), but not in Caucasians (HR = 1.07; 95% CI: 0.91, 1.25; P_{linear trend} = 0.42), though the test for interaction was not statistically significant (P_interaction = 0.099).ConclusionsFindings from this prospective cohort study do not support a significant longitudinal association between toenail zinc concentrations and incidence of asthma among American young adults. Future studies are needed to confirm our findings.     

Ginkgo biloba extract for essential hypertension: A systemic review

BackgroundGinkgo biloba extract (GBE), a traditional natural herbal product, is often used in the treatment of essential hypertension (EH) as complementary therapy in China and European countries.AimTo critically assess the current clinical evidence of efficacy and safety of GBE for EH.Methods7 electronic databases (Cochrane Library, PubMed, EMBASE, VIP, CBM, Wanfang data, and CNKI) were searched to identify randomized controlled trials (RCTs) of GBE for EH. Methodological quality was assessed independently using the Cochrane Handbook for Systematic Reviews of Interventions.ResultsA total of 9 RCTs with 1012 hypertensive patients were identified and reviewed. Most RCTs were of high risk of bias with flawed study design and poor methodological quality. 6 trials demonstrated potential positive effect of GBE as complementary therapy on BP reduction when compared with antihypertensive drug therapy; however, it was not associated with a statistically significant effect on both SBP and DBP reduction in 3 other trials. Despite the positive findings, there were so many methodological limitations and significant clinical heterogeneity. Most of the trials did not report adverse effects, and the safety of GBE is still uncertain.ConclusionNo confirmative conclusions on the efficacy and safety of GBE for EH could be drawn. More rigorous trials are warranted to support their clinical use.     

The Effect of Ginger (Zingiber officinale) on Platelet Aggregation: A Systematic Literature Review

BackgroundThe potential effect of ginger on platelet aggregation is a widely-cited concern both within the published literature and to clinicians; however, there has been no systematic appraisal of the evidence to date.MethodsUsing the PRISMA guidelines, we systematically reviewed the results of clinical and observational trials regarding the effect of ginger on platelet aggregation in adults compared to either placebo or baseline data. Studies included in this review stipulated the independent variable was a ginger preparation or isolated ginger compound, and used measures of platelet aggregation as the primary outcome.ResultsTen studies were included, comprising eight clinical trials and two observational studies. Of the eight clinical trials, four reported that ginger reduced platelet aggregation, while the remaining four reported no effect. The two observational studies also reported mixed findings.DiscussionMany of the studies appraised for this review had moderate risks of bias. Methodology varied considerably between studies, notably the timeframe studied, dose of ginger used, and the characteristics of subjects recruited (e.g. healthy vs. patients with chronic diseases).ConclusionThe evidence that ginger affects platelet aggregation and coagulation is equivocal and further study is needed to definitively address this question.