Probiotics for the prevention of Clostridium difficile-associated diarrhea in adults and children.

BACKGROUND: Antibiotics are widely prescribed; however they can cause disturbances in gastrointestinal flora which may lead to reduced resistance to pathogens such as Clostridium difficile (C. difficile). Probiotics are live organisms thought to balance the gastrointestinal flora. OBJECTIVES: The primary objectives were to assess the efficacy and safety of probiotics for preventing Clostridium difficile-associated diarrhea (CDAD) or C. difficile infection in adults and children. SEARCH METHODS: On February 21, 2013 we searched PubMed (1966-2013), EMBASE (1966-2013), Cochrane Central Register of Controlled Trials (The Cochrane Library 2013, Issue 1), CINAHL (1982-2013), AMED (1985-2013), and ISI Web of Science. Additionally, we conducted an extensive grey literature search including contact with industry representatives. SELECTION CRITERIA: Randomized controlled (placebo, alternative prophylaxis, or no treatment control) trials investigating probiotics (any strain, any dose) for prevention of CDAD, or C. difficile infection were considered for inclusion. DATA COLLECTION AND ANALYSIS: Two authors independently and in duplicate extracted data and assessed risk of bias using pre-constructed, and piloted, data extraction forms. Any disagreements were resolved by a third adjudicator. For articles published in abstract form only, further information was sought by contacting principal authors. The primary outcome was the incidence of CDAD. Secondary outcomes included the incidence of C. difficile infection, adverse events, antibiotic-associated diarrhea (AAD) and length of hospital stay. Dichotomous outcomes (e.g. incidence of CDAD) were pooled using a random-effects model to calculate the relative risk and corresponding 95% confidence interval (95% CI). Continuous outcomes (e.g. length of hospital) were pooled using a random-effects model to calculate the mean difference and corresponding 95% CI. Sensitivity analyses were conducted to explore the impact of missing data on efficacy and safety outcomes. For the sensitivity analyses, we assumed that the event rate for those participants in the control group who had missing data was the same as the event rate for those participants in the control group who were successfully followed. For the probiotic group we calculated effects using the following assumed ratios of event rates in those with missing data in comparison to those successfully followed: 1.5:1, 2:1, 3:1, and 5:1. To explore possible explanations for heterogeneity, a priori subgroup analysis were conducted on probiotic species, dose, adult versus pediatric population, and risk of bias.The overall quality of the evidence supporting each outcome was assessed using the GRADE criteria. MAIN RESULTS: A total of 1871 studies were identified with 31 (4492 participants) meeting eligibility requirements for our review. Overall 11 studies were rated as a high risk of bias due mostly to missing outcome data. A complete case analysis (i.e. participants who completed the study) of those trials investigating CDAD (23 trials, 4213 participants) suggests that probiotics significantly reduce this risk by 64%. The incidence of CDAD was 2.0% in the probiotic group compared to 5.5% in the placebo or no treatment control group (RR 0.36; 95% CI 0.26 to 0.51). Sixteen of 23 trials had missing CDAD data ranging from 5% to 45%. These results proved robust to sensitivity analyses of plausible and worst-plausible assumptions regarding missing outcome data and were similar whether considering trials in adults versus children, lower versus higher doses, different probiotic species, or higher versus lower risk of bias. Our judgment is that the overall evidence warrants moderate confidence in this large relative risk reduction. We downgraded the overall quality of evidence for CDAD to 'moderate' due to imprecision. There were few events (154) and the calculated optimal information size (n = 8218) was more than the total sample size. With respect to the incidence of C. difficile infection, a secondary outcome, pooled complete case results from 13 trials (961 participants) did not show a statistically significant reduction. The incidence of C. difficile infection was 12.6% in the probiotics group compared to 12.7% in the placebo or no treatment control group (RR 0.89; 95% CI 0.64 to 1.24). Adverse events were assessed in 26 studies (3964 participants) and our pooled complete case analysis indicates probiotics reduce the risk of adverse events by 20% (RR 0.80; 95% CI 0.68 to 0.95). In both treatment and control groups the most common adverse events included abdominal cramping, nausea, fever, soft stools, flatulence, and taste disturbance. For the short-term use of probiotics in patients that are not immunocompromised or severely debilitated, we consider the strength of this evidence to be moderate. AUTHORS' CONCLUSIONS: Based on this systematic review and meta-analysis of 23 randomized controlled trials including 4213 patients, moderate quality evidence suggests that probiotics are both safe and effective for preventing Clostridium difficile-associated diarrhea.

Enhancing Student Learning by Integrating Anatomy in Pathology Teaching.

BACKGROUND: Vertically integrating anatomy into pathology curricula is beneficial for student-centered learning. This study investigates the effectiveness of this approach on student learning outcomes. ACTIVITY: Learners received a vertically integrated pathology curriculum; their pre- and post-course test data were collected. RESULTS AND DISCUSSION: Two-hundred thirty-two learners participated in the activity. Upon completing the activity, their average post-course performance was significantly better than that of a control group (P < 0.05), with significantly higher scores on solving pathology case problems (P < 0.05), as well as on retaining anatomy concepts (P < 0.05). Vertically integrating anatomy in pathology instruction is an effective educational approach.

Positive correlation between the use of complementary and alternative medicine and internal health locus of control.

BACKGROUND: Because many people with chronic medical conditions use complementary and alternative medicine (CAM), understanding their psychosocial characteristics may be useful for identifying effective interventions. The health locus of control (HLOC) measures the perception of controlling one's own health outcomes by various attributes. People with a high internal HLOC believe that the outcome of their own health seeking is related to their behavior or personal investment. Earlier evidence has shown that a higher internal HLOC is a predictive factor of positive treatment outcomes. OBJECTIVE: This study measured the correlation between the degree of CAM use and the level of HLOC. DESIGN: An online cross-sectional survey was conducted via public bulletin boards and invitational e-mails. Data from 123 usable responses were analyzed for bivariate correlation between CAM use and HLOC. Subjective reports of various medical modalities were classified into six CAM domains and one conventional biomedicine domain. Subscales of HLOC included internal, chance, and powerful others. Chronic conditions, health status, and demographics were self-reported. RESULTS: Internal HLOC significantly correlated with CAM use (Spearman's rho, P < .004) but not with conventional medicine use (Spearman's rho, P > .130). Further analysis of this correlation for those people with chronic conditions could not identify a particular domain used more by people with a high internal HLOC (P > .187), but the lesser use of conventional medicine was significant (P < .031). CONCLUSION: Complementary and alternative medicine is either empowering or has empowered patients to use CAM. People who use CAM may have a better prognosis and better management of chronic conditions.

Polysaccharide-K augments docetaxel-induced tumor suppression and antitumor immune response in an immunocompetent murine model of human prostate cancer.

Advanced castration-resistant prostate cancer has high mortality rates and limited treatment options. Novel therapies are needed to better contend with this disease. Polysaccharide-K® (PSK), an extract of the mushroom Trametes versicolor, has immunomodulatory and tumor suppressive activities. PSK is used in Asia as a cancer immunotherapy. However, its benefit in combination with taxanes for prostate cancer is unknown. We examined whether PSK would enhance docetaxel-induced apoptosis and augment anti-tumor immune responses in orthotopic tumors using transgenic adenocarcinoma of the mouse prostate (TRAMP)-C2-bearing mice. Combining PSK with docetaxel induced significantly higher tumor suppression than either treatment alone (p<0.05), including a reduction in tumor proliferation and enhanced apoptosis. Combined PSK and docetaxel treatment led to a lower decrease in number of white blood cells than docetaxel alone, an effect accompanied by increased numbers of tumor-infiltrating CD4+ and CD8+ T cells. PSK with or without docetaxel significantly enhanced mRNA expression of IFN-γ compared to control, but did not significantly alter T-regulatory FoxP3 mRNA expression in tumors. PSK also augmented docetaxel-induced splenic natural killer cell cytolytic activity against YAC-1 target cells (p=0.045). This study is the first to show that PSK enhances docetaxel-induced prostate cancer tumor suppression, apoptosis and antitumor responses.

Phase 1 Clinical Trial of Trametes versicolor in Women with Breast Cancer.

Introduction. Orally administered preparations from the Trametes versicolor (Tv) mushroom have been hypothesized to improve immune response in women with breast cancer after standard chemotherapy and radiotherapy. Methods. A phase I, two-center, dose escalation study was done to determine the maximum tolerated dose of a Tv preparation when taken daily in divided doses for 6 weeks after recent completion of radiotherapy. Eleven participants were recruited and nine women completed the study. Each cohort was comprised of three participants given one of three doses of Tv (3, 6, or 9 grams). Immune data was collected pre- and postradiation, at 3 on-treatment time points and after a 3-week washout. Results. Nine adverse events were reported (7 mild, 1 moderate, and 1 severe), suggesting that Tv was well tolerated. Immunological results indicated trends in (1) increased lymphocyte counts at 6 and 9 grams/day; (2) increased natural killer cell functional activity at 6 grams/day; (3) dose-related increases in CD8(+) T cells and CD19(+) B cells , but not CD4(+) T cells or CD16(+)56(+) NK cells. Conclusion. These findings show that up to 9 grams/day of a Tv preparation is safe and tolerable in women with breast cancer in the postprimary treatment setting. This Tv preparation may improve immune status in immunocompromised breast cancer patients following standard primary oncologic treatment.

Immune defects in breast cancer patients after radiotherapy.

The purpose of this study was to evaluate the immune status of women with stage I-III breast cancer after receiving external beam radiotherapy (RT). Fourteen stage I-III, estrogen or progesterone receptor-positive or-negative (FER/PR +\-), postsurgical breast cancer patients undergoing a standard course of chemotherapy and radiation were studied. Complete blood counts (CBC) with differential, phagocytic activity, natural killer (NK) cell functional activity, and tumor necrosis factor-alpha (TNF-alpha) and interferon-gamma cytokine activity were measured immediately before and for the six weeks following the completion of radiation therapy. Fatigue levels after completion of RT were measured using the Functional Assessment of Chronic Illness Therapy (FACIT)-Fatigue scale. Nonparametric statistical methods (Wilcoxon rank and Spearman correlations) were used to analyze the data. Compared with postchemotherapy, following the completion of RT, these breast cancer patients showed lymphopenia, low functional activity of natural killer lymphocytes, decreased monocyte phagocytic activity, and decreased TNF-alpha production but no neutropenia, no anemia, and no change in interferon-gamma production. Lymphocyte count did not return to normal by the end of the 6-week post-RT observation period. The severity of lymphopenia and low natural killer cell activity was related to RT area but not radiation dose. Patients did not report significant fatigue levels for the 6 weeks after completing RT. Significant decreases in the numbers and functions of cells from both the innate and adaptive immune system were detected following a standard course of radiation therapy for the treatment of breast cancer. Immune deficits in lymphocyte populations and TNF-alpha production, should they persist, may have consequences for immune response to residual or recurrent malignancy following completion of conventional treatment. The use of adjunctive immune therapies which target these specific defects may be warranted in the post-treatment period.

Two proteins that form a complex are required for 7-methylguanosine modification of yeast tRNA.

7-methylguanosine (m7G) modification of tRNA occurs widely in eukaryotes and bacteria, is nearly always found at position 46, and is one of the few modifications that confers a positive charge to the base. Screening of a Saccharomyces cerevisiae genomic library of purified GST-ORF fusion proteins reveals two previously uncharacterized proteins that copurify with m7G methyltransferase activity on pre-tRNA(Phe). ORF YDL201w encodes Trm8, a protein that is highly conserved in prokaryotes and eukaryotes and that contains an S-adenosylmethionine binding domain. ORF YDR165w encodes Trm82, a less highly conserved protein containing putative WD40 repeats, which are often implicated in macromolecular interactions. Neither protein has significant sequence similarity to yeast Abd1, which catalyzes m7G modification of the 5' cap of mRNA, other than the methyltransferase motif shared by Trm8 and Abd1. Several lines of evidence indicate that both Trm8 and Trm82 proteins are required for tRNA m7G-methyltransferase activity: Extracts derived from strains lacking either gene have undetectable m7G methyltransferase activity, RNA from strains lacking either gene have much reduced m7G, and coexpression of both proteins is required to overproduce activity. Aniline cleavage mapping shows that Trm8/Trm82 proteins modify pre-tRNAPhe at G46, the site that is modified in vivo. Trm8 and Trm82 proteins form a complex, as affinity purification of Trm8 protein causes copurification of Trm82 protein in approximate equimolar yield. This functional two-protein family appears to be retained in eukaryotes, as expression of both corresponding human proteins, METTL1 and WDR4, is required for m7G-methyltransferase activity.

A conserved family of Saccharomyces cerevisiae synthases effects dihydrouridine modification of tRNA.

Dihydrouridine modification of tRNA is widely observed in prokaryotes and eukaryotes, as well as in some archaea. In Saccharomyces cerevisiae every sequenced tRNA has at least one such modification, and all but one have two or more. We have used a biochemical genomics approach to identify the gene encoding dihydrouridine synthase 1 (Dus1, ORF YML080w), using yeast pre-tRNA(Phe) as a substrate. Dus1 is a member of a widespread family of conserved proteins, three other members of which are found in yeast: YNR015w, YLR405w, and YLR401c. We show that one of these proteins, Dus2, encoded by ORF YNR015w, has activity with two other substrates: yeast pre-tRNA(Tyr) and pre-tRNA(Leu). Both Dus1 and Dus2 are active as a single subunit protein expressed and purified from Escherichia coli, and the activity of both is stimulated in the presence of flavin adenine dinucleotide. Dus1 modifies yeast pre-tRNA(Phe) in vitro at U17, one of the two positions that are known to bear this modification in vivo. Yeast extract from a dus1-A strain is completely defective in modification of yeast pre-tRNAPhe, and RNA isolated from dus1-delta and dus2-delta strains is significantly depleted in dihydrouridine content.