جستجوی مقالات مرتبط با کلیدواژه « kit » در نشریات گروه « پزشکی »

Mutations in the receptor tyrosine kinase KIT are the major cause of gastrointestinal stromal tumors. KIT-mediated activation of the RAS/RAF/MEK/ERK and PI3 kinase/AKT pathways plays an important role in KIT mutant-mediated cell transformation.

The frequently seen primary KIT mutations W557K558del and V560D, and the secondary KIT mutations V654A and N822K, in gastrointestinal stromal tumors were stably transfected into Ba/F3 cells. Cell proliferation was examined with a CCK kit, and cell survival and cell cycle were examined by flow cytometry. Cell signaling was examined by western blot.

We found that farnesyltransferase inhibitors tipifarnib and lonafarnib, which inhibit RAS activity, inhibited ERK activation mediated by both wild-type and KIT mutants, which often occur in gastrointestinal stromal tumors. Correspondingly, both wild-type and KIT mutant-mediated cell survival and proliferation were inhibited by both inhibitors. Imatinib is used as the first-line targeted therapy for gastrointestinal stromal tumors in the clinic. In our study, both inhibitors increased imatinib-mediated inhibition of cell survival and proliferation induced by both wild-type and KIT mutants. Similar to the primary KIT mutations, secondary mutations of KIT-induced ERK activation and cell response were inhibited by both inhibitors.

Our results suggested the potential benefit of farnesyltransferase inhibitors either alone or combined with imatinib in the treatment of gastrointestinal stromal tumors carrying KIT mutations.

This paper presents a novel, rapid, and simple method for the determination of sarcosine. The surface of a glass plate was modified with 3-(methacryloxy)propyltrimethoxysilane. Then, a sarcosine-imprinted polymer was grafted on the glass plate by copolymerization of the vinyl end groups with a functional monomer and a cross-linking agent. The synthesized polymers were characterized by Fourier transform infrared spectroscopy and scanning electron microscopy. In the subsequent step, the determination of sarcosine was conducted using the synthesized kit in optimized conditions. The synthesized grafted plate was able to absorb sarcosine selectively in the presence of other amino acids, showing that the proposed method enabled the rapid determination of sarcosine.

KIT is a protooncogene that encodes for the KIT oncoprotein, which is a transmembrane tyrosine kinase growth factor receptor that holds a critical role in a variety of normal physiological and pathological processes including angiogenesis. KIT has been shown to be involved in tumorigenesis, contributing to the development of gastrointestinal carcinoma and leukemia. A link between KIT overexpression and breast cancer development has previously been reported. In the current study, we explored KIT gene expression and exonic copy number variants (CNV) and the relationship with angiogenesis (CD34) and the clinicopathological features of breast cancer.

MLPA technique was used to determine the CNV in 64 breast cancer tumor samples from patients diagnosed with primary sporadic breast cancer. Results were confirmed by quantitative PCR. Expression of KIT and CD34 was determined using immunohistochemistry (IHC).

Our results show that 28.1% of the tumor samples from patients with primary sporadic breast cancer had CNV in the KIT gene. Among the breast tumor samples, 54.7% showed positive KIT expression. The expression of the CD34 angiogenesis marker was reported in 43.8% of the tumor samples as low, 42.2% as moderate and 14.1% as high. A significant correlation between increased CNV of KIT exons, a high level of angiogenesis (CD34) and increased tumor grade was observed (p< 0.05).

A significant correlation between the KIT CNV and the angiogenesis marker was found. Examining KIT expression and CNV has the potential to function as a biomarker for tyrosine kinase inhibitor drugs in breast cancer.

Extracting of genomic DNA with the proper quality and quantity is critical in the molecular identification of insects, whose morphological identification is problematic and affected by specific stage of life, size and sex. Also, storing insects under inappropriate conditions can have damaging effects on the quantity and quality of extracted DNA. Thus, choosing an appropriate protocol to provide pure DNA from these insects is essential.

In the present study to achieve an efficient method for DNA extraction from insect, we have applied and compared three common methods including (CTAB, Chelex and using commercial kit (animal tissue DNA isolation kit)). The quantity and quality of the extracted DNA were measured in two thermal conditions when DNA was stored at both -20 °C and -80 °C. The concentration of DNA extracted was measured on the Thermo Scientific NanoDrop 2000c.

The greatest and lowest average nucleic acid concentration of parasitoids were recorded for CTAB and Chelex. The mean DNA yield of parasitoids (Scelionidae) from different collection preservatives indicated that the greatest average DNA yield was recorded for 95% and 99.8% ethanol respectively, and 75% ethanol had the lowest value of average DNA yield.

CTAB method as a suitable method. and storing insects in -80°C at 99.8% ethanol as suitable methods with high performance to DNA extraction of parasitoids was suggested.

To study the c-Kit expression in the gallbladder of cholesterol lithogenic guinea pig model and the effect of Artemisia capillaris Thunb on interstitial cells of Cajal (ICCs).
A total of 45 guinea pigs were randomly assigned into three groups: the control group (guinea pigs fed a standard diet, normal group); the model group (guinea pigs fed a cholesterol gallstone-inducing diet); and the Chinese medicine group (guinea pigs fed the cholesterol gallstone-inducing diet and treated with A. capillaris through intragastric administration, therapy group). Each group had 15 guinea pigs. The gallbladders of the guinea pigs were harvested after 8 weeks. C-Kit expression was detected using an immunohistochemistry staining, real-time PCR, and Western blot analyses. The effect of A. capillaris on ICCs was evaluated by muscle strip contraction experiments.
C-Kit expression significantly decreased in the gallbladder of model group, but increased in the Chinese medicine group. The Contractility of guinea pig gallbladder muscle strip significantly improved in the Chinese medicine group.
Our results indicated that A. capillaris improves gallbladder impairment by up-regulating c-Kit expression, and it also can improve the contractile response of in vitro guinea pig gallbladder muscle strips.

Melanoma causes the greatest morbidity and mortality of all skin cancers. Mucosal melanoma is a rare but highly aggressive neoplasm. According to previous studies the prevalence of KIT mutations in acral lentiginous and mucosal melanomas is relatively low (less than 15 20%), but it can have profound therapeutic implications for localized high risk or metastatic diseases. Our goal was to evaluate c-Kit expression in different types of primary and metastatic melanoma to discriminate potential candidates for targeted therapy. We designed a cross-sectional study and selected 50 cases of malignant melanoma (primary, metastatic cutaneous, and mucosal) from the affiliated hospitals of Shiraz University of Medical Sciences in the period of 2008 to 2012. Immunohistochemistry for KIT expression was performed. Multistage sampling method was selected for sampling and chi-square test was used for statistical analysis. In our study, male to female ratio was 1.77. The male sex was correlated with higher tumor stage (p< 0.05). 62% (n= 31) of cases showed at least 5% of KIT-positive cells, consist of 18% (n= 9) with 5–50%, 16% (n= 8) with 51–95%, and 28% (n= 14) of cases showed more than 95% of cells expressing KIT. But in 38% (n= 19) of cases KIT expression was less than 5% of positive cells. Tumor stage was positively correlated with tumor cell immunoreactivity and intensity (p< 0.05). Metastatic melanoma showed lower percentage (43%) of positivity. Intensity of staining and percentage of positive cells were positively correlated (p< 0.001). In primary melanomas, significant KIT expression was found by immunohistochemistry, which may be useful to screen the patients for advising to KIT mutation analysis and targeted therapy.

99mTc-TRODAT-1 is a promising new radiopharmaceutical with the potential for routine use as the radiopharmaceutical for dopamine transporters scintigraphy as far as its image quality and daily availability are concerned. Here we describe the development of a freeze-dried kit formulation based on the tricine exchange labeling approach for the preparation of this radiopharmaceutical in a clinical setting. A freeze-dried formulation contained of TRODAT-1, tricine, SnCl2 and manitol was prepared. Labeling was performed by addition of 1480 MBq 99mTc sodium pertechnetate in a total volume of 2 mL and incubation for 15 min in a boiling water bath. Radiochemical analysis involved ITLC and HPLC methods. The stability of radioconjugate was checked in the presence of human serum at 37 °C up to 24 h. 99mTc-TRODAT-1 was prepared with a radiochemical purity of >95% and a high stability up to 24 h of the final preparation, and retained biological activity. The developed kit formulation forms the basis for further clinical evaluation of this promising new radiopharmaceutical.