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1.
Fourier transform infrared (FTIR) spectroscopic imaging is an emerging microscopy modality for clinical histopathologic diagnoses as well as for biomedical research. Spectral data recorded in this modality are indicative of the underlying, spatially resolved biochemical composition but need computerized algorithms to digitally recognize and transform this information to a diagnostic tool to identify cancer or other physiologic conditions. Statistical pattern recognition forms the backbone of these recognition protocols and can be used for highly accurate results. Aided by biochemical correlations with normal and diseased states and the power of modern computer-aided pattern recognition, this approach is capable of combating many standing questions of traditional histology-based diagnosis models. For example, a simple diagnostic test can be developed to determine cell types in tissue. As a more advanced application, IR spectral data can be integrated with patient information to predict risk of cancer, providing a potential road to precision medicine and personalized care in cancer treatment. The IR imaging approach can be implemented to complement conventional diagnoses, as the samples remain unperturbed and are not destroyed. Despite high potential and utility of this approach, clinical implementation has not yet been achieved due to practical hurdles like speed of data acquisition and lack of optimized computational procedures for extracting clinically actionable information rapidly. The latter problem has been addressed by developing highly efficient ways to process IR imaging data but remains one that has considerable scope for progress. Here, we summarize the major issues and provide practical considerations in implementing a modified Bayesian classification protocol for digital molecular pathology. We hope to familiarize readers with analysis methods in IR imaging data and enable researchers to develop methods that can lead to the use of this promising technique for digital diagnosis of cancer.  相似文献   
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High-level expression of the low-Km glucose transporter isoform GLUT-1 is characteristic of many cultured tumor and oncogene-transformed cells. In this study, we tested whether induction of GLUT-1 occurs in tumors in vivo. Normal mouse beta islet cells express the high-Km (approximately 20 mM) glucose transporter isoform GLUT-2 but not the low-Km (1 to 3 mM) GLUT-1. In contrast, a beta cell line derived from an insulinoma arising in a transgenic mouse harboring an insulin-promoted simian virus 40 T-antigen oncogene (beta TC3) expressed very low levels of GLUT-2 but high levels of GLUT-1. GLUT-1 protein was not detectable on the plasma membrane of islets or tumors of the transgenic mice but was induced in high amounts when the tumor-derived beta TC3 cells were grown in tissue culture. GLUT-1 expression in secondary tumors formed after injection of beta TC3 cells into mice was reduced. Thus, high-level expression of GLUT-1 in these tumor cells is characteristic of culture conditions and is not induced by the oncogenic transformation; indeed, overnight culture of normal pancreatic islets causes induction of GLUT-1. We also investigated the relationship between expression of the different glucose transporter isoforms by islet and tumor cells and induction of insulin secretion by glucose. Prehyperplastic transgenic islet cells that expressed normal levels of GLUT-2 and no detectable GLUT-1 exhibited an increased sensitivity to glucose, as evidenced by maximal insulin secretion at lower glucose concentrations, compared with that exhibited by normal islets. Further, hyperplastic islets and primary and secondary tumors expressed low levels of GLUT-2 and no detectable GLUT-1 on the plasma membrane; these cells exhibited high basal insulin secretion and responded poorly to an increase in extracellular glucose. Thus, abnormal glucose-induced secretion of insulin in prehyperplastic islets in mice was independent of changes in GLUT-2 expression and did not require induction of GLUT-1 expression.  相似文献   
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cdc28-1N is a conditional allele that has normal G1 (Start) function but confers a mitotic defect. We have isolated seven genes that in high dosage suppress the growth defect of cdc28-1N cells but not of Start-defective cdc28-4 cells. Three of these (CLB1, CLB2, and CLB4) encode proteins strongly homologous to G2-specific B-type cyclins. Another gene, CLB3, was cloned using PCR, CLB1 and CLB2 encode a pair of closely related proteins; CLB3 and CLB4 encode a second pair. Neither CLB1 nor CLB2 is essential; however, disruption of both is lethal and causes a mitotic defect. Furthermore, the double mutant cdc28-1N clb2::LEU2 is nonviable, whereas cdc28-4 clb2::LEU2 is viable, suggesting that the cdc28-1N protein may be defective in its interaction with B-type cyclins. Our results are consistent with CDC28 function being required in both G1 and mitosis. Its mitotic role, we believe, involves interaction with a family of at least four G2-specific cyclins.  相似文献   
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Fluorescence in situ hybridization (FISH) with chromosome-specific DNA libraries was performed on samples from eight patients with de novo chromosomal duplications. In five cases, the clinical phenotype and/or cytogenetic evaluations suggested a likely origin of the duplicated material. In the remaining three cases, careful examination of the GTG-banding pattern indicated multiple possible origins; hybridization with more than one chromosome-specific library was performed on two of these cases. In all cases, FISH conclusively identified the chromosomal origin of the duplicated material. In addition, the hybridization pattern was useful in quantitatively delineating the duplication in two cases.  相似文献   
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Otitis media is a common childhood infection, frequently requiring antibiotics. With high rates of antibiotic prescribing and increasing antibiotic resistance, new strategies in otitis media prevention and treatment are needed. The aim of this study was to assess the in vitro inhibitory activity Streptococcus salivarius BLIS K12 against otitis media pathogens. Efficacy of the bacteriocin activity of S. salivarius BLIS K12 against the otitis media isolates was assessed using the deferred antagonism test. Overall, 48% of pathogenic isolates exhibited some growth inhibition by S. salivarius BLIS K12. S. salivarius BLIS K12 can inhibit the in vitro growth of the most common pathogens.

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Adequate dietary calcium (Ca) intake is essential for bone accretion, peak bone mass (PBM) attainment, bone quality and strength during the mammalian growth period. Severe Ca deficiency during growing age results in secondary hyperparathyroidism (SHPT) and poor bone quality and strength. However, the impact of moderate Ca deficiency during rats early growth period on bone health and the reversibility with supplementing calcium later in adult life remains unclear. Female Sprague-Dawley (SD) rats (postnatal 28th day, P28) were initiated either with a moderate calcium-deficient diet (MCD, 0.25% w/w Ca) or a control diet (0.8% w/w Ca, control group) till P70. Thereafter, MCD rats were continued either with MCD diet or supplemented with calcium diet (0.8% w/w Ca, calcium supplemented group, CaS) till P150. Another group (control rats) were fed 0.8% w/w Ca containing diet from P28 till P150.MCD group, as compared to the control group, had significantly reduced serum ionized Ca and procollagen type 1 N-terminal propeptide (P1NP) at P70 while no significant change was observed in serum corrected Ca, inorganic phosphate (P), alkaline phosphatase (ALP), 25-hydroxy vitamin D [25(OH)D], intact parathyroid hormone (iPTH), and urinary C-terminal telopeptide of collagen 1 (CTX-1), Ca, and P. Femoral and tibial metaphysis in MCD rats had significantly reduced linear growth, cortical and trabecular volumetric BMD (vBMD), trabecular microarchitecture (BV/TV%, trabecular thickness, separation and number, structural model index and connectivity density), cortical thickness, and bone stiffness despite the absence of secondary hyperparathyroidism (SHPT). Continued MCD at P70–P150 results in persistence of compromised bone strength while calcium supplementation (CaS group) improved all the parameters related to bone strength and microarchitecture. Our results indicate that uncorrected moderate/subclinical calcium deficiency in growing rats can result in poor bone quality and strength despite the absence of SHPT. This finding could have relevance in children with poor calcium intake in childhood and adolescence.  相似文献   
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Abstract

Cardiotoxicity is one amongst the adverse effect of Osimertinib delineate in clinical trials and related to escalating doses. To triumph over the drawbacks of Osimertinib, in this study, we tend to delineate the design, synthesis, in vitro biological analysis of a series of novel reversible selective T790M inhibitors with minimal cardiotoxicity. Amongst the virtually sorted compounds; compound 18 and 74 have been located to be the foremost active compounds of the series with IC50 value of 0.88, 0.92?μM in cellular assay and 0.56, 0.62?μM in enzymatic assay, against double mutant L858R/T790M EGFR. Additionally, they showed much less affinity toward wild-type (WT)-EGFR with minimal cardiotoxicity.  相似文献   
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