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81.
KRAS is mutated in ∼40% of colorectal cancer (CRC), and there are limited effective treatments for advanced KRAS mutant CRC. Therefore, it is crucial that downstream mediators of oncogenic KRAS continue to be studied. We identified p190RhoGAP as being phosphorylated in the DLD1 CRC cell line, which expresses a heterozygous KRAS G13D allele, and not in DKO4 in which the mutant allele has been deleted by somatic recombination. We found that a ubiquitous binding partner of p190RhoGAP, p120RasGAP (RasGAP), is expressed in much lower levels in DKO4 cells compared to DLD1, and this expression is regulated by KRAS. Rescue of RasGAP expression in DKO4 rescued Rho pathway activation and partially rescued tumorigenicity in DKO4 cells, indicating that the combination of mutant KRAS and RasGAP expression is crucial to these phenotypes. We conclude that RasGAP is an important effector of mutant KRAS in CRC.  相似文献   
82.

Background

Til date, none of the diagnostic techniques available for the detection of female genital tuberculosis (FGTB) are 100% accurate. We therefore, proposed to use the endometrial tissue biopsies (ETBs), ovarian tissue biopsies (OTBs) and pelvic aspirated fluids (PAFs) for the diagnosis of FGTB among infertile women by conventional versus molecular methods.

Methodology/Principal Findings

A total of 302 specimens were collected both from 202 infertile women highly suspected of having FGTB on laparoscopy examination and 100 control women of reproductive age. Out of 302 specimens, 150 (49.67%) were ETBs, 95 (31.46%) were OTBs and 57 (18.87%) were PAFs. All specimens were tested by conventional techniques, later compared with multi-gene PCR for the detection of Mycobacterium tuberculosis (MTB) and correlated with laparoscopic findings. The presence of MTB DNA was observed in 49.5% of ETBs, 33.17% of OTBs and 5.44% of PAF specimens collected from highly suspected FGTB patients. All women of control group were confirmed as negative for tuberculosis. The conventional methods showed 99% to 100% specificity with a low sensitivity, ranging from 21.78% to 42.08% while hematoxylin and eosin staining showed a sensitivity of 51.48%. Multi-gene PCR was found to have much higher sensitivity of 70.29% with MTB64 gene, 86.63% with 19 kDa antigen gene at species and TRC4 element at regional MTB complex and 88.12% with 32 kDa protein gene at genus level. The specificity of multi-gene PCR was 100%. Compared with culturing and Ziehl-Neelsen''s staining, multi-gene PCR demonstrated improvement in the detection of FGTB (χ2 = 214.612, 1 df, McNemar''s test value <0.0001).

Conclusions Significance

We suggest site specific sampling, irrespective of sample type and amplification of the 19 kDa antigen gene in combination with TRC4 element as a successful multi-gene PCR for the diagnosis of FGTB and differentiation of mycobacterial infection among endo-ovarian tissue biopsies and PAFs taken from infertile women.  相似文献   
83.
The first junior European Calcium Society online meeting, held October 20–21, 2020, aimed to promote junior researchers in the Ca2+ community. The meeting included four scientific sessions, covering Ca2+ research from molecular detail to whole organisms. Each session featured one invited speaker and three speakers selected based on submitted abstracts, with the overall aim of actively involving early-career researchers. Consequently, the meeting underlined the diversity of Ca2+ physiology, by showcasing research across scales and Kingdoms, as presented by a correspondingly diverse speaker panel across career stages and countries. In this meeting report, we introduce the visions of the junior European Calcium Society board and summarize the meeting content.  相似文献   
84.
Aquatic Ecology - Information on the feeding habits of species is essential to develop appropriate conservation actions. This study aimed to assess spatial and temporal variation in the diet of the...  相似文献   
85.
86.
Colorectal cancer (CRC) is the second leading cause of death from cancer. The MET receptor tyrosine kinase and/or its ligand HGF are frequently amplified or overexpressed in CRC. It is known that tyrosine phosphorylated proteins are involved in progression and metastasis of colorectal cancer; however, little is known about the MET phospho-proteome in CRC. High resolution mass spectrometry was used to characterize immunoaffinity-purified, phosphotyrosine (pY)-containing tryptic peptides of the MET-expressing CRC cell model, DLD1. A total of 266 unambiguously identified pY sites spanning 168 proteins were identified. Quantification of mass spectrometry ion currents identified 161 pY sites, including many not previously linked to MET signaling, that were modulated in abundance by HGF stimulation. Overlay of these data with protein-protein interaction data sets suggested that many of the identified HGF-modulated phospho-proteins may be directly or indirectly associated with MET. Analysis of pY sequence motifs indicated a prevalence of Src family kinase consensus sequences, and reciprocal signaling between Src and MET was confirmed by using selective small molecule inhibitors of these kinases. Therefore, using quantitative phospho-proteomics profiling, kinase modulation by ligand and inhibitors, and data integration, an outline of the MET signaling network was generated for the CRC model.  相似文献   
87.
A metabolic flux based methodology was developed for modeling the metabolism of a Chinese hamster ovary cell line. The elimination of insignificant fluxes resulted in a simplified metabolic network which was the basis for modeling the significant metabolites. Employing kinetic rate expressions for growing and non-growing subpopulations, a logistic model was developed for cell growth and dynamic models were formulated to describe culture composition and monoclonal antibody (MAb) secretion. The model was validated for a range of nutrient concentrations. Good agreement was obtained between model predictions and experimental data. The ultimate goal of this study is to establish a comprehensive dynamic model which may be used for model-based optimization of the cell culture for MAb production in both batch and fed-batch systems.  相似文献   
88.
Two-spotted spider mite, Tetranychus urticae Koch, is one of the most important pests of agricultural products that have a global distribution. Now, the control is dependent on the use of chemical pesticides. The effects of the sublethal concentrations (LC10 and LC25) of the essential oil of Cinnamomum zeylanicum were evaluated on some parameters of the life table of the pest, at the constant temperature of 30?°C, relative humidity of 40?±?5% and photoperiod of 16L: 8D. Our results showed that the essential oil of cinnamon is effective on female adult stage. Lethal concentration at which 50% mortality (LC50) for the essential oils is from C. zeylanicum on female adult mite was 23.39?μl/L air. Sublethal concentrations of the essential oil of C. zeylanicum also impair the natural biology of the mite. Concentrations of sublethal of essential oil decreased age-specific fertility (mx) of T. urticae compared with the control. Sublethal concentrations (LC10 and LC25) have reduced the life expectancy (ex) in egg stage. Sublethal effects of the essential oil of C. zeylanicum and its impact on T. urticae management are discussed.  相似文献   
89.
Nowadays, alpha‐2‐macroglobulin (A2M) gene has allocated escalating interest among several genes involved in the pathogenesis of avascular necrosis of the femoral head (ANFH). This molecule could interact with several osteogenic‐related proteins. It was reported that adrenocorticotropic hormone (ACTH) affects bones through its receptor located on osteoblasts, suggesting it as a potential target in ANFH treatment. In this study, the effect of ACTH on A2M expression was investigated in osteoblasts as well as during the differentiation of human mesenchymal stem cells (MSCs) into osteoblasts. In this study, MSCs derived from bone marrow were isolated and purified using Ficoll gradient and several passaging. MSCs were characterized by induction with osteogenic and adipogenic medium followed by Oil Red O, Alizarin Red and alkaline phosphatase staining. Besides, MSCs were exposed to various concentrations of ACTH to evaluate the cell variability by MTT assay. MSCs and differentiated osteoblasts were treated with 10?8 molar ACTH for 16 and 26 days, respectively. Then, the total RNA was extracted and A2M expression was quantified by real‐time qPCR. The protein expression levels of osteoblast markers including alkaline phosphatase (ALPL) and bone gamma‐carboxyglutamate protein (BGLAP) were also measured. The results showed that A2M expression in cells treated with ACTH was up‐regulated significantly compared to the control group. Similarly, the expression of osteoblast gene markers including ALPL and BGLAP was significantly increased. ACTH, as an osteoblastic differentiation enhancer, up‐regulates A2M, which promotes osteoblastic differentiation probably through TGF‐β induction.  相似文献   
90.

The present study was conducted to assess the effects of combined and singular dietary administration of PrimaLac® and potassium diformate (KDF) on growth performance, feed utilization, digestive enzymes activity, and some physiological parameters of rainbow trout (Oncorhynchus mykiss) juvenile. Three hundred sixty rainbow trout juveniles (25 ± 1.8 g) were randomly stocked in 300-L tanks (30 fish/tank), and fed three times daily on a basal diet (control), diets incorporated with 12 g kg−1 KDF (FT1), 1.5 g kg−1 PrimaLac® (FT2), and combination of 1.5 g kg−1 probiotic and 12 g kg−1 KDF (FT3) in triplicates, for 8 weeks. At the end of feeding trial, growth performance, body composition, digestive enzymes, liver enzymes, and biochemical parameters were measured. Our results revealed that combined administration of PrimaLac® and KDF (FT3) exhibited significantly higher weight gain and specific growth rate (SGR) compared to other groups (P < 0.05). Glucose and cortisol levels showed no significant differences between fish fed different test diets (P > 0.05). The highest lipase, protease and amylase activity were observed in group of fish fed FT3 followed by FT2 and FT1. Besides, the diets FT2 and FT3 led to significantly lower of ALP, ALT, and AST compared to control group. The present results indicated that combined administration of PrimaLac® and KDF can be considered as a beneficial feed additive and growth promotor for O. mykiss juvenile.

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