No abstract

The human gut microbiota are critical for preserving the health status because they are required for digestion and nutrient acquisition, the development of the immune system, and energy metabolism. The gut microbial composition is greatly influenced by the colonization of the recalcitrant pathogen Helicobacter pylori (H. pylori) and the conventional antibiotic regimens that follow. H. pylori is considered to be the main microorganism in gastric carcinogenesis, and it appears to be required for the early stages of the process. However, a non-H. pylori microbiota profile is also suggested, primarily in the later stages of tumorigenesis. On the other hand, specific groups of gut microbes may produce beneficial byproducts such as short-chain fatty acids (acetate, butyrate, and propionate) that can modulate inflammation and tumorigenesis pathways. In this review, we aim to present how H. pylori influences the population of the gut microbiota to modify the host immunity and trigger the development of gastric carcinogenesis. We will also highlight the effect of the gut microbiota on immunotherapeutic approaches such as immune checkpoint blockade in cancer treatment to present a perspective for further development of innovative therapeutic paradigms to prevent the progression of H. pylori-induced stomach cancer.

In this article, the polypropylene (PP) nanocomposites containing nanoclay particles and basalt fiber (BF) are prepared in the presence of maleic anhydride grafted PP (PP- g-MA) as compatibilizing agent. The Charpy impact behavior of PP/PP- g-MA/clay nanocomposites and PP/PP- g-MA/Clay/BF nanocomposites at room temperature (25°C), cryogenic temperature (–196°C), and high temperature (120°C) is presented. The BFs prevented the PP matrix from plastic deformation, but the impact strength improvement of nanocomposites is obtained when nanoclay in the PP matrix resists the propagation of cracks. The fracture surfaces are examined with scanning electron microscopy (SEM).

Introduction. As a common interferer in clinical chemistry, lipemic specimens could be a source of significant analytical errors. Ultracentrifugation has been by far the only reliable, but an unavailable and expensive, method to eliminate the lipemic effect. Materials and Methods. Among the daily samples, those with triglyceride >400 mg/dL (4.6 mmol/L) and also turbid were selected, divided into three groups, based on triglyceride concentration, and three pooled serums were made for each group. Then all pooled serums were investigated by using a DIRUI biochemistry analyzer CS-800 for routine chemistry tests in different methods including direct measurement, serum blank, serum dilution, and measurement after ultracentrifugation. Results. According to our study, there were significant differences before and after ultracentrifugation in all lipemic levels and for all parameters except for alanine aminotransferase (ALT), alkaline phosphatase (ALP), bilirubin, and uric acid. Based on allowable inaccuracy for each parameter, calcium, magnesium, phosphorus, total protein, iron, total iron-binding capacity (TIBC), urea, and chloride are being influenced by all lipemic degree and neither serum dilution nor using serum blank is as effective as ultracentrifuge for elimination. Serum blank was a proper method of lipid removal for the measurement of glucose. Conclusion. Lipemia is a well-known interferer in clinical chemistry. One cannot avoid lipemia, but fortunately, severe lipemia is a rare phenomenon in the laboratory, and for assessment of some analytes in a lower degree of lipemia, use of serum blank eliminates the need for ultracentrifuge.

Despite voluminous studies into teachers' cognition and the role of teachers' beliefs in their practices, not many studies have addressed the impact of teachers' epistemological beliefs (EB, beliefs about the source of knowledge) on their teaching styles. In this study, a mixed design research method was adopted to show English language teachers' epistemological beliefs, teaching styles and possible relationships between EB and teaching styles. To do this, a sample of 200 EFL teachers participated in the quantitative phase of the study to fill out the teaching style inventory (Grasha, Teaching with style, 2002) and epistemological beliefs scale (Chan and Elliott, Teaching and Teacher Education 20:817-831, 2004). In qualitative phase, 20 participants of this sample volunteered to attend the semi-structured interviews. Both quantitative and qualitative analyses indicated that facilitator style is the dominant style of teaching and learners should not assume teachers as mere source of knowledge and should use different resources to learn the language. Regression analyses and interview results showed that EFL teachers teaching style is informed by their EB. Implication and limitation of the research were discussed in detail in the paper.