Changes in gut microbial flora after Roux-en-Y gastric bypass and sleeve gastrectomy and their effects on post-operative weight loss.

Bariatric surgery affects gut microbial flora due to the anatomical and physiological changes it causes in the gastrointestinal tract. Understanding the interaction between the gut flora, the type of bariatric surgery and weight loss may help improve bariatric surgery outcomes. This study was designed to compare the effects of Roux-en-Y Gastric Bypass (RYGB) and Sleeve Gastrectomy (SG) on two main phyla of the gut microbiota in humans and evaluate their potential effect on weight changes. Thirty morbidly obese patients were divided into two groups and underwent laparoscopic SG or laparoscopic RYGB. The patients' weight changes and fecal samples were evaluated at baseline and 6 months after the surgery. A microbial flora count was carried out of the phyla Bacteroidetes and Firmicutes and Bacteroides Fragilis. Changes in the abundance of the flora and their correlation with weight loss were analyzed. After 6 months, the patients with a history of RYGB showed a significant decrease in stool Bacteroidetes while the reduction in the SG group was insignificant. Firmicutes abundance was almost unchanged following SG and RYGB. There was no significant change in Bacteroides Fragilis abundance in either of the two groups, but a positive correlation was observed between Bacteroides Fragilis and weight loss after SG and RYGB. Bariatric surgery can affect gut microbiota. It can be concluded that these changes are dependent on many factors and may play a role in weight loss.

Brief outcome of five decades of battle with infectious diseases in Iran.

According to WHO health profile, Iran has better situation in controlling some infection disease like leprosy, dengue fever, tularemia and hepatitis B than United States, even though Iran is in a more dangerous area than the USA. Achieving optimum control for infectious disease in the Middle East requires huge financial costs, equipment and a great time. Some of Iran's actions to control infectious diseases include: special attention of the Iran government to the health issue, training and developing human resources, membership and close cooperation with international organizations like WHO, detecting and monitoring emerging diseases before their arrival and distribution in Iran, expanding and updating national immunization and vaccination program since 1992, national project implementation titled "Health system development plan", supplying and manufacturing most of drugs required in Iran by the Iranian companies as a strategic planning, great coordination between different departments of the MOHME and other relevant institutions to Iran Army and Ministry of Intelligence to prevent the emergence of bioterrorism, and etc. We believe that Iran has obtained an acceptable score in the control of infectious diseases; but it still has very big challenges to reach the ideal level.

The Trend of ripk1/ripk3 and mlkl Mediated Necroptosis Pathway in Patients with Different Stages of Prostate Cancer as Promising Progression Biomarkers.

BACKGROUND: Programmed cell death is critical to maintain tissue homeostasis. Necroptosis, as well as apoptosis, has been considered as another form of regulated cell death which can be used as an effective way to overcome apoptosis-resistant tumor tissue growth. The aim of present study was to test whether or not ripk1, ripk3, or mlkl expression levels, as the key necroptotic modulators in different stages of prostate tumor growth. METHODS: Sixty-seven prostate tissues representing histologically confirmed cancer were selected. The cancer samples were categorized into 4 different stages based on cellular differentiation, tumor growth rate, and extra tissue expansion to regional lymph nodes, average PSA levels, and tumor volume. RNA extraction, cDNA synthesis and quantitative real time PCR were done based on standard guidelines. RESULTS: No statistically significant changes in ripk1 expression showed in all three stages (stage II to IV). The expression pattern of ripk3 represented a remarkable elevation in early stage, while, predominantly repressed in final cancer stage (IV). Also, there has been a significant negative correlation between ripk3 gene expression and tumor size and PSA levels. CONCLUSIONS: We cannot exclude the importance of the key regulator proteins in development and progression of prevalent lethal disease like prostate cancer. The ripk1/ripk3 mediated necroptosis pathway is more activated in early stages of prostate cancer via induced ripk3 expression, while repressed during prostate cancer final stages. Also, the repression of ripk3 is related to elevation of both PSA levels and tumor volume which represented the tumor progression in final stages.

Differentiation of human umbilical cord mesenchymal stem cell into germ-like cell under effect of co-culture with testicular cell tissue.

Supplements produced by mouse testicular cells (mTCs) and the interaction between cells can increase the differentiation rate of human umbilical cord mesenchymal stem cells (hUCMSCs) into the germ-like cells. We studied the differentiation rate of hUCMSCs into the germ-like cells under effect of mTCs co-culturing. Isolated hUCMSCs from postpartum human umbilical cords were cultured. Then, the expression of mesenchymal (CD73, CD90 and CD105) and haematopoietic (CD34 and CD45) markers of hUCMSCs were confirmed by flow cytometry. Then, the hUCMSCs were cultured in four distinct groups: (a) control, (b) co-culture until D0, (c) co-culture until D5 and (d) co-culture until D10, in order to differentiate into the germ-like cells. After 10 days, the expression of OCT4, VASA, Fragilis and SYCP3 genes were examined by Real-Time qPCR. The flow cytometry indicated a high expression of mesenchymal markers and a low expression of haematopoietic markers (CD73:98.6%, CD90: 99.1%, CD105: 99.5%, CD34: 4.22% and CD45: 2.54%). The expression of OCT4 decreased during the time while the expression of VASA, Fragilis and SYCP3 markers increased in the co-culture with testicular cells (p value <.05). Co-culture with mTCs may be used as an effective method to differentiate hUCMSCs into germ-like cells.

Overexpression of the Long Non-Coding RNA NeSt and FOXCUT in Early Stages of Prostate Cancer Samples as Promising Biomarkers.

BACKGROUND: Prostate cancer is one of the most common cancers in males worldwide. Recently, it is well characterized that long non-coding RNAs (lncRNA) play critical roles in the initiation, development, and progression of prostate cancer. NeST, an intergenic lncRNA, was found to be a positive regulator of the pro-inflammatory cytokine, IFN-É£, which is responsible for both antitumor immunity properties as well as tumor evasion. FOXCUT, an-other lncRNA, is mainly a regulator of transcription factor, FOXC1 that is believed to be involved in tumor development and progression. METHODS: In a case-control study, 66 paraffin-embedded prostate tissues representing 36 pathologically confirmed cancer and 30 control samples were examined. The cancer samples were classified in a total of three stages based on PSA levels, tumor volume, and Gleason score. RNA extraction was performed for quantitative determination of IFN-É£, lncRNA NeSt, and lncRNA FOXCUT gene expression in both case and control prostate tissues. RESULTS: Our results showed that NeST lncRNA was significantly up-regulated in prostate cancer samples compared to control, while NeST lncRNA and IFN-É£ gene expression was detected mainly in early stages of prostate cancer. The patients with higher NeST and FOXCUT expression had poor clinical features including PSA levels and tumor volume comparing those with lower expression. Moreover, there was a strong correlation between lncRNA FOXCUT and IFN-É£ expression. CONCLUSIONS: Our data suggests that lncRNA NeST and lncRNA FOXCUT may be able to be introduced as novel molecules involved in prostate cancer development and may provide a potential prognostic biomarker and therapeutic target.

Identification of an intestinal microbiota signature associated with hospitalized patients with diarrhea.

As an important global health challenge, diarrhea kills nearly two million people each year. Postinfectious irritable bowel syndrome (IBS) usually manifests itself as the diarrhea-predominant subtype. Small intestinal bacterial overgrowth has been observed more frequently in patients with IBS compared to healthy controls. However, the pathophysiology of IBS is not fully understood, and based on recent evidences, altered gut microbiota is involved in the pathogenesis of IBS. Therefore, we aimed to compare the microbiome in hospitalized patients with diarrhea and healthy individuals. Thirty patients and 10 healthy controls were included into this case-control study. Microbial count was performed using quantitative real-time polymerase chain reaction method using bacterial 16S rRNA gene. Clostridium cluster IV and Bacteroides were significantly more frequent in the patients compared with the healthy individuals (p = 0.02 and 0.023, respectively). However, the quantity of Enterococcus and Bifidobacterium groups were significantly higher in healthy controls than in diarrheal group (p = 0.000076 and 0.001, respectively). The results showed that the number of bacteria in all bacterial groups was significantly different between healthy individuals and diabetic group, whereas the difference between the healthy group and IBS was not significant for Bifidobacterium group. The findings of this study outlined the relationship between diarrhea, IBS, and diabetes disease and bacterial composition. It could be concluded that modifying the bacterial composition by probiotics can be helpful in the control and management of the mentioned disease.

Therapeutic bacteria to combat cancer; current advances, challenges, and opportunities.

Successful treatment of cancer remains a challenge, due to the unique pathophysiology of solid tumors, and the predictable emergence of resistance. Traditional methods for cancer therapy including radiotherapy, chemotherapy, and immunotherapy all have their own limitations. A novel approach is bacteriotherapy, either used alone, or in combination with conventional methods, has shown a positive effect on regression of tumors and inhibition of metastasis. Bacteria-assisted tumor-targeted therapy used as therapeutic/gene/drug delivery vehicles has great promise in the treatment of tumors. The use of bacteria only, or in combination with conventional methods was found to be effective in some experimental models of cancer (tumor regression and increased survival rate). In this article, we reviewed the major advantages, challenges, and prospective directions for combinations of bacteria with conventional methods for tumor therapy.

Antimicrobial resistance, prevalence of resistance genes, and molecular characterization in intestinal Bacteroides fragilis group isolates.

Since the level of antimicrobial resistance in Bacteroides fragilis has increased, monitoring the antimicrobial susceptibility could be necessary. The objectives of this study were to (i) investigate the prevalence of species, the occurrence of reduced antimicrobial susceptibility (E-test method), and antibiotic resistance genes in the B. fragilis group and (ii) evaluate the prevalence of enterotoxigenic B. fragilis and the distribution of bft gene subtypes in hospitalized patients. As many as 475 isolates out of 250 stool samples were detected to be B. fragilis group by using conventional biochemical tests (API-32A system) and multiplex-PCR. In addition, 48.2%, 13.9%, 76.6%, and 1.2% of B. fragilis group isolates were resistant (according to EUCAST breakpoint) to piperacillin-tazobactam, meropenem, clindamycin, and metronidazole, respectively. Six metronidazole-resistant strains were isolated; B. fragilis (n: 3), B. thetaiotaomicron, B. vulgates, and B. ovatus. The presence of the cfiA, cepA, ermF, and nim genes was observed in 3.8%, 15.9%, 34.1%, and 0.7% of the B. fragilis isolates, respectively. One hundred thirty-two B. fragilis isolates (27.8%)and 21 B  fragilis isolates (15.9%) turned out to be bft gene positive by multiplex-PCR; eleven isolates (52.4%) harbored bft-1, eight isolates (38%) harbored bft-2 isotypes, and two isolates (9.5%) harbored bft-3 isotype (16.66%). These bacteria harbor antimicrobial resistance genes that could be transferred to other susceptible intestinal strains. Further investigations on lineage analysis are needed for a better understanding of these bacteria in Iran.

Prevalence and antimicrobial susceptibility pattern of toxigenic Clostridium difficilestrains isolated in Iran

Background/aim: Clostridium difficile is a frequent cause of nosocomial infections and has become a major public health concern in developed nations. In the present study, the prevalence and antimicrobial susceptibility pattern of toxigenic C. difficile strains isolated in Iran were investigated. Materials and methods: Between June 2016 and May 2017, 2947 inpatient fecal samples were taken from symptomatic adult hospitalized patients in different units of 32 care facilities in Tehran, Iran. C. difficile strains were identified by microbiological/biochemical methods. Susceptibility to 20 antimicrobials was measured by E-test method. Toxin-specific immunoassays and cytotoxicity assays were used to determine in vitro toxin production Results: Out of 2947 fecal samples, 538 (18.25%) C. difficile isolates were obtained among those with suspected CDI. In E-test method, all C. difficile isolates were susceptible to fidaxomicin, vancomycin, amoxicillin/clavulanate, and meropenem and were resistant to penicillin G. The prevalence of multidrug resistant C. difficile was 69.33% (373/538). Among 538 C. difficile, 147 (27.32%), 169 (31.41%), and 222 (41.26%) isolates were TcdA+/TcdB+, TcdA-/TcdB+, and TcdA-/TcdB-, respectively Conclusion: The results evidently support the hypothesis of a probable role of toxigenic strains of C. difficile in developing gastrointestinal complaints in patients with diarrhea

Fosfomycin: mechanisms and the increasing prevalence of resistance.

There are challenges regarding increased global rates of microbial resistance and the emergence of new mechanisms that result in microorganisms becoming resistant to antimicrobial drugs. Fosfomycin is a broad-spectrum bactericidal antibiotic effective against Gram-negative and certain Gram-positive bacteria, such as Staphylococci, that interfere with cell wall synthesis. During the last 40 years, fosfomycin has been evaluated in a wide range of applications and fields. Although numerous studies have been done in this area, there remains limited information regarding the prevalence of resistance. Therefore, in this review, we focus on the available data concerning the mechanisms and increasing resistance regarding fosfomycin.