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991.
Fibroblast growth factor ligands and receptors (FGF and FGFR) play critical roles in tumorigenesis, and several drugs have been developed to target them. We report the biologic correlates of FGF/FGFR abnormalities in diverse malignancies. The medical records of patients with cancers that underwent targeted next generation sequencing (182 or 236 cancer-related genes) were reviewed. The following FGF/FGFR genes were tested: FGF3, 4, 6, 7, 10, 12, 14, 19, 23 and FGFR1, 2, 3, and 4. Of 391 patients, 56 (14.3%) had aberrant FGF (N = 38, all amplifications) and/or FGFR (N = 22 including 5 mutations and one FGFR3-TACC3 fusion). FGF/FGFR aberrations were most frequent in breast cancers (26/81, 32.1%, p = 0.0003). In multivariate analysis, FGF/FGFR abnormalities were independently associated with CCND1/2, RICTOR, ZNF703, RPTOR, AKT2, and CDK8 alterations (all P < 0.02), as well as with an increased median number of alterations (P < 0.0001). FGF3, FGF4, FGF19 and CCND1 were co-amplified in 22 of 391 patients (5.6%, P < 0.0001), most likely because they co-localize on the same chromosomal region (11q13). There was no significant difference in time to metastasis or overall survival when comparing patients harboring FGF/FGFR alterations versus those not. Overall, FGF/FGFR was one of the most frequently aberrant pathways in our population comprising patients with diverse malignancies. These aberrations frequently co-exist with anomalies in a variety of other genes, suggesting that tailored combination therapy may be necessary in these patients.  相似文献   
992.

Background

The study investigated the presence of CTX-M-15 type extended spectrum beta-lactamases (ESBL), compared their genetic arrangements and plasmid types in gram negative isolates of hospital and food origin in north-east India. From September 2013 to April 2014, a total of 252 consecutive, non-duplicate clinical isolates and 88 gram negative food isolates were selected. Phenotypic and molecular characterization of ESBL genes was performed. Presence of integrons and gene cassettes were analyzed by integrase and 59 base-element PCR respectively. The molecular environments surrounding bla CTX-M and plasmid types were investigated by PCR and PCR-based replicon typing respectively. Transformation was carried out to assess plasmid transfer. Southern blotting was conducted to localize the bla CTX-M-15 genes. DNA fingerprinting was performed by ERIC-PCR.

Results

Prevalence of ESBL was found to be 40.8% (103/252) in clinical and 31.8% (28/88) in food-borne isolates. Molecular characterization revealed the presence of 56.3% (58/103) and 53.5% (15/28) bla CTX-M-15 in clinical and food isolates respectively. Strains of clinical and food origin were non-clonal. Replicon typing revealed that IncI1 and IncFII plasmid were carrying bla CTX-M-15 in clinical and food isolates and were horizontally transferable. The ISEcp1 element was associated with bla CTX-M-15 in both clinical and food isolates.

Conclusions

The simultaneous presence of resistance determinants in non-clonal isolates of two different groups thus suggests that the microbiota of common food products consumed may serve as a reservoir for some of the drug resistance genes prevalent in human pathogens.  相似文献   
993.
Coronavirus disease (COVID-19) is an infection of the respiratory system caused by single standard RNA viruses named as Severe Acute Respiratory Syndrome 2 (SARS-CoV-2). The disease appeared as a serious problem and the leading cause of death in human beings throughout the world. The main source of different phytochemicals are plants, which helps in the development of new drugs against various ailments. Islam is comprehensive religion and a complete code of life for Muslims. The teaching of Islam, according to the Holy Quran and Hadith are universal for the benefit of humanity. Islam believes that every ailment is from God and who made the disease definitely made its medication. There is a complete guideline with regard to taking measures against infectious diseases such as quarantine and seeking medicinal treatment. The research objective is to gather the knowledge of medicinal plants described in the Holy Quran or utilized by the Prophet (SAW) for the treatment of different ailments or advised to use them to boost immunity and strengthen the body. Scientists across the globe have found these plants beneficial for many diseases and have antiviral potential. In present study, the six plant species including Olea europaea, Nigella sativa, Allium Sativum, Allium cepa, Zingiber officinale and Cassia senna were selected which contain phytochemicals like Calcium Elenolate, Thymoquinone, S-Allylcysteine, Dipropyl Disulfide, Sesquiterpene, Monoterpene, Pelargonidin 3-Galactoside ion and Kaempferol. The phytochemicals monoterpene (from Zingiber officinale) shows best interaction with target proteins RdRP, 3CLPro, ACE2. Calcium Elonate (from olive) bonds with 3CLPro, ACE2 and Kemoferol and Pelargomidine (from Senna Makki) bonds with RdRP, ACE2. The ligands show a unique set of intersections i.e. hydrogen bonding, and alkyl interaction. These medicinal plants can be utilized immediately for the treatment of COVID-19 as their safety is already established. This treatment can enhance recovery when combined with other treatments. Furthermore, the screening of bioactive compounds or phytochemicals found in these plants can be utilized to design new therapeutic drug to treat COVID-19 pandemic.  相似文献   
994.
Tomato aphid (Myzus persicae) is a destructive insect pest of tomato responsible for huge losses in the production as well in the vegetable industry. In the present in vitro study two protein elicitors, PeaT1 and PeBL1 were considered to study their efficacies to exhibit defense response against tomato aphid. Three different concentrations of both protein elicitors were applied on the tomato seedlings. After the application of PeaT1 and PeBL1, population growth rates of tomato aphid were decreased as compared to the control treatment. In host preference assay, the tomato aphid showed a preference to build a colony on the control as compared to the treated tomato plant, because tomato leaves provided hazardous surface for aphid after the formation of wax and trichome. The concentrations of protein showed significant (p < 0.05) results in life-history traits of the aphid. Jasmonic acid (JA), salicylic acid (SA) and ethylene (ET) showed significant accumulation in tomato seedlings treated with PeaT1 and PeBL1. Elicitors treated plants produced resistance against M. persicae. Our finding suggests that PeaT1 and PeBL1 have shown high potentials against the damage of M. persicae, and both elicitors could be used as novel biological tools against tomato aphid.  相似文献   
995.
As one of the most lethal malignancies, lung cancer is considered to account for approximately one-fifth of all malignant tumours-related deaths worldwide. This study reports the synthesis and in vitro biological assessment of two sets of 3-methylbenzofurans (4a–d, 6a–c, 8a–c and 11) and 3-(morpholinomethyl)benzofurans (15a–c, 16a–b, 17a–b and 18) as potential anticancer agents towards non-small cell lung carcinoma A549 and NCI-H23 cell lines, with VEGFR-2 inhibitory activity. The target benzofuran-based derivatives efficiently inhibited the growth of both A549 and NCI-H23 cell lines with IC50 spanning in ranges 1.48–47.02 and 0.49–68.9 µM, respectively. The three most active benzofurans (4b, 15a and 16a) were further investigated for their effects on the cell cycle progression and apoptosis in A549 (for 4b) and NCI-H23 (for 15a and 16a) cell lines. Furthermore, benzofurans 4b, 15a and 16a displayed good VEGFR-2 inhibitory activity with IC50 equal 77.97, 132.5 and 45.4 nM, respectively.  相似文献   
996.

In the present study, we aimed to investigate the modulatory effects of a potential probiotic bacterium Lactobacillus gasseri ATCC 33323 on Helicobacter pylori-induced inflammatory response and gene expression in human gastric adenocarcinoma (AGS) cell line. The gastric epithelial cells were coinfected with a collection of H. pylori clinical strains alone or in combination with L. gasseri at a multiplicity of infection (MOI) of 1:100 for each bacterium, and incubated for different time points of 3, 6, and 12 h. IL-8 secretion from coinfected AGS cells after incubation at each time point was measured by an enzyme-linked immunosorbent assay (ELISA). The mRNA expression of IL-8, Bcl-2, β-catenin, integrin α5, and integrin β1 genes was determined by quantitative RT-PCR amplification of total RNA extracted from coinfected epithelial cells. L. gasseri significantly (P < 0.05 and P < 0.01) decreased the production of IL-8 in AGS cells coinfected with H. pylori strains at 6 h post-infection. We also detected that L. gasseri significantly (P < 0.05) down-regulated the gene expression level of IL-8 in H. pylori-stimulated AGS cells after 6 and 12 h of coinfection. Similarly, L. gasseri caused a significant decrease (P < 0.05) in mRNA expression of Bcl-2, β-catenin, integrin α5, and integrin β1 genes in AGS cells at 3 and 6 h after infection with H. pylori strains as compared with non-infected control cells. In conclusion, our results demonstrated that L. gasseri ameliorates H. pylori-induced inflammation and could be developed as a supplementation to the current treatment regimens administrated against H. pylori infection.

  相似文献   
997.
After acute DNA damage, the cell arrests S-phase progression by inhibiting origin initiation and fork progression to repair damaged DNA. The intra-S-phase checkpoint kinase Chk1 phosphorylates Cdc25A to target the latter for degradation by CRL1β-TrCP and so inhibit origin firing. The mechanism for inhibiting fork progression, however, has not been identified. Here, we show that degradation of p12, the fourth subunit of DNA polymerase δ, is critical for inhibiting fork progression. CRL4Cdt2 is an E3 ligase that ubiquitinates and degrades p12 after UV treatment. Cells expressing a stable form of p12 exhibit UV-resistant DNA synthesis. DNA fiber assay and alkaline-sucrose gradient assay demonstrate that the impairment of fork progression after DNA damage requires p12 degradation. These results suggest that ubiquitination of p12 through CRL4Cdt2 and subsequent degradation form one mechanism by which a cell responds to DNA damage to inhibit fork progression.  相似文献   
998.
999.
1000.
Cubilin, (CUBN; also known as intrinsic factor-cobalamin receptor [Homo sapiens Entrez Pubmed ref NM_001081.3; NG_008967.1; GI: 119606627]), located in the epithelium of intestine and kidney acts as a receptor for intrinsic factor – vitamin B12 complexes. Mutations in CUBN may play a role in autosomal recessive megaloblastic anemia. The current study investigated the possible role of CUBN in evolution using phylogenetic testing. A total of 588 BLAST hits were found for the cubilin query sequence and these hits showed putative conserved domain, CUB superfamily (as on 27th Nov 2012). A first-pass phylogenetic tree was constructed to identify the taxa which most often contained the CUBN sequences. Following this, we narrowed down the search by manually deleting sequences which were not CUBN. A repeat phylogenetic analysis of 25 taxa was performed using PhyML, RAxML and TreeDyn softwares to confirm that CUBN is a conserved protein emphasizing its importance as an extracellular domain and being present in proteins mostly known to be involved in development in many chordate taxa but not found in prokaryotes, plants and yeast.. No horizontal gene transfers have been found between different taxa.  相似文献   
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