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371.
Glioblastoma multiforme (GBM) is one of the most common and malignant form of adult brain tumor with a high mortality rate and dismal prognosis. The present standard treatment comprising surgical resection followed by radiation and chemotherapy using temozolomide can broaden patient's survival to some extent. However, the advantages are not palliative due to the development of resistance to the drug and tumor recurrence following the multimodal treatment approaches due to both intra- and intertumoral heterogeneity of GBM. One of the major contributors to temozolomide resistance is O6-methylguanine-DNA methyltransferase. Furthermore, deficiency of mismatch repair, base excision repair, and cytoprotective autophagy adds to temozolomide obstruction. Rising proof additionally showed that a small population of cells displaying certain stem cell markers, known as glioma stem cells, adds on to the resistance and tumor progression. Collectively, these findings necessitate the discovery of novel therapeutic avenues for treating glioblastoma. As of late, after understanding the pathophysiology and biology of GBM, some novel therapeutic discoveries, such as drug repurposing, targeted molecules, immunotherapies, antimitotic therapies, and microRNAs, have been developed as new potential treatments for glioblastoma. To help illustrate, “what are the mechanisms of resistance to temozolomide” and “what kind of alternative therapeutics can be suggested” with this fatal disease, a detailed history of these has been discussed in this review article, all with a hope to develop an effective treatment strategy for GBM.  相似文献   
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S. pneumoniae, commonly known as pneumococcus, is a naturally competent Gram-positive bacterium and is the major cause of pneumonia in elderly and children in developing countries. This pathogen is associated with respiratory diseases affected by pollution. The objective of this work was determining the effect of ash and environmental dust from the burning of sugarcane on pneumococci bacterial transformation. The transformation capacity of the Pn360 pneumococci strain was performed using the assays of DNA donor of mutant for luxS gene. Thus, the transformation tests were performed in contact with dust collected in the southwestern region of Brazil (important region where burning of sugar cane is present in the agriculture). The use of degradative practices in the sugar cane agriculture in Brazil was involved in the transformation capacity of the S. pneumoniae. This phenomenon includes important consequences for public health concerning to resistance acquisition and new virulence factors of this important infection. In conclusion, we obtained important results concerning the action of environmental pollution in Streptococcus pneumoniae transformation, increasing the DNA acquisition for this pathogen.  相似文献   
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Summary From these observations, it can be concluded that V-forms and other angular cell arrangements in Arthrobacter atrocyaneus can arise in several different ways. As summarized diagrammatically in Fig. 5, the irregular cell conjunctions so characteristic of these corynebacteria might be the result of snapping post-fission movement, the germination of adjacent coccoid elements, or the angular growth (germination) of rod-shaped organisms. As yet, the mechanisms underlying each of these processes remain to be clarified.Dedicated, with affection and appreciation, to Professor Dr. Ernst Georg Pringsheim on his 80th birthday  相似文献   
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Journal of Plant Research - Under natural conditions plants are generally subjected to complex scenarios of combined or sequential environmental stresses. Among the various components of plant...  相似文献   
377.
The human gastrointestinal (GI) tract microbiota acts like a virtual organ and is suggested to be of great importance in human energy balance and weight control. This study included 40 monozygotic (MZ) twin pairs to investigate the influence of the human genotype on GI microbiota structure as well as microbial signatures for differences in body mass index (BMI). Phylogenetic microarraying based on 16S rRNA genes demonstrated that MZ twins have more similar microbiotas compared with unrelated subjects (P<0.001), which allowed the identification of 35 genus-like microbial groups that are more conserved between MZ twins. Half of the twin pairs were selected on discordance in terms of BMI, which revealed an inverse correlation between Clostridium cluster IV diversity and BMI. Furthermore, relatives of Eubacterium ventriosum and Roseburia intestinalis were positively correlated to BMI differences, and relatives of Oscillospira guillermondii were negatively correlated to BMI differences. Lower BMI was associated with a more abundant network of primary fiber degraders, while a network of butyrate producers was more prominent in subjects with higher BMI. Combined with higher butyrate and valerate contents in the fecal matter of higher BMI subjects, the difference in microbial networks suggests a shift in fermentation patterns at the end of the colon, which could affect human energy homeostasis.  相似文献   
378.
Autoimmune diseases are characterized by the loss of self-tolerance, leading to immune-mediated tissue destruction and chronic inflammation. Tyrosine kinase 2 (TYK2) protein plays a key role in immunity and apoptosis pathways. Studies have reported associations between single nucleotide polymorphisms (SNPs) in the TYK2 gene and autoimmune diseases; however, results are still inconclusive. Thus, we conducted a systematic review followed by meta-analysis. A literature search was performed to find studies that investigated associations between TYK2 SNPs and autoimmune diseases (multiple sclerosis, systemic lupus erythematosus, Crohn’s disease, ulcerative colitis, psoriasis, rheumatoid arthritis, type 1 diabetes, and inflammatory bowel disease). Pooled odds ratios (OR) with 95 % CI were calculated using random (REM) or fixed (FEM) effects models in the Stata 11.0 Software. Thirty-four articles were eligible for inclusion in the meta-analyses, comprising 9 different SNPs: rs280496, rs280500, rs280523, rs280519, rs2304256, rs12720270, rs12720356, rs34536443, and rs35018800. Meta-analysis results showed the minor alleles of rs2304256, rs12720270, rs12720356, rs34536443, and rs35018800 SNPs were associated with protection against autoimmune diseases. Moreover, the A allele of the rs280519 SNP was associated with risk for systemic lupus erythematosus. Our meta-analyses demonstrated that the rs2304256, rs12720270, rs12720356, rs34536443, rs35018800, and rs280519 SNPs in the TYK2 gene are associated with different autoimmune diseases.  相似文献   
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Hydrobiologia - Species proliferate through evolutionary mechanisms but coexist through ecological dynamics. As such, it might be expected that mechanisms of speciation and species maintenance...  相似文献   
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