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451.
Keyur S. Vyas Jeremy Ryan Bariola Robert W. Bradsher 《Current fungal infection reports》2008,2(4):227-231
Blastomyces dermatitidis, the etiologic agent of blastomycosis, is endemic to certain areas of North America and other continents and can cause a
variety of clinical manifestations that range from subclinical to life-threatening infections. Delineation of its ecology
and epidemiology has been difficult because of the lack of rapid, sensitive, and specific noninvasive diagnostic tests. Despite
efforts to develop such tests for clinical use, diagnosis of infection is still based on direct visualization of the organism
in histopathologic or cytologic specimens and growth in the microbiologic laboratory. Serologic tests and skin testing have
been hampered by low sensitivity and specificity caused by cross-reactivity with other endemic mycoses and are not commercially
available. An antigen assay is now commercially available, but it also has significant cross-reactivity with other mycoses,
especially histoplasmosis. The keys to diagnosis remain a high index of suspicion and knowledge of the disease’s varied clinical
manifestations. 相似文献
452.
Hytham N Fageeh Hammam Ibrahim Fageeh Samar Saeed Khan Prabhadevi C. Maganur Nishant Vyas Vikrant R. Patil A. Thirumal Raj Hosam Ali Baeshen Shankargouda Patil 《Saudi Journal of Biological Sciences》2021,28(5):3069-3075
Periodontitis is a condition that occurs because of inflammation-mediated tissue degeneration. Many studies have been conducted to identify inflammatory molecules in periodontitis, but the well-defined role of cells from the immune system in the progression of periodontitis as well as in gingival tissue degeneration has not been appropriately established. The objective of the present study was to characterize the monocytes isolated from the gingival crevicular fluid (GCF) in patients with periodontitis. GCF was obtained from periodontitis patients and healthy controls. Cytokine levels of CCL2 were evaluated by ELISA in GCF samples. CD14+ monocytes were separated using magnetic sorting from GCF. RT-qPCR was performed to assess the gene expression. Cytometric bead array analysis was performed to analyze the levels of cytokines and chemokines in the secretome of cells. CD14+ monocytes from GCF secreted higher levels of CCL2 and showed elevated expression of genes responsible for monocyte migration. Additionally, upon lipopolysaccharide stimulation, these monocytes secreted higher levels of inflammatory cytokines and chemokines. This investigation aids in understanding the inflammatory microenvironment of periodontitis by characterizing GCF in terms of infiltrated CD14+ monocytes, cytokines, and molecules secreted by these monocytes, which are specific for cellular differentiation. 相似文献
453.
Summary Proteoliposomes made by a butanol-sonication technique from electric organ presynaptic membranes showed choline transport activity. In contrast to intact nerve terminals, the uptake of choline was dissociated from its conversion to acetylcholine in this preparation. The kinetics of choline uptake by proteoliposomes was best described by two Michaelis-Menten components. At a low concentration of choline, uptake was inhibited by hemicholinium-3 and required external Na+ and, thus, closely resembled high-affinity choline uptake by intact cholinergic nerve terminals. Choline transport could be driven by the Na+ gradient and by the transmembrane potential (inside negative) but did not directly require ATP. External Cl–, but not a Cl– gradient, was needed for choline transport activity. It is suggested that internal K+ plays a role in the retention of choline inside the proteoliposome. Proteoliposomes should prove a useful tool for both biochemical and functional studies of the highaffinity choline carrier.Abbreviations ACh
acetylcholine
- HC-3
hemicholinium-3
- ChAT
choline acetyltransferase 相似文献
454.
Haw Hsiao Chen-Yen Lin Sunil Vyas Kuang-Yuh Huang J. Andrew Yeh Yuan Luo 《Journal of biophotonics》2021,14(2):e202000335
Confocal endoscopy has been widely used to obtain fine optically sectioned images. However, confocal endomicroscopic images are formed by point-by-point scanning in both lateral and axial directions, which results in long image acquisition time. Here, an endomicroscope with telecentric configuration is presented to achieve nonmechanical and rapid axial scanning for volumetric fluorescence imaging. In our system, optical sectioning in wide-field fashion is obtained through HiLo imaging with a digital micromirror device. Axial scanning, without mechanical moving parts, is conducted by digital focus adjustment using an electrically tunable lens, offering constant magnification and contrast. We demonstrate imaging performance of our system with optically sectioned images using fluorescently labeled beads, as well as ex vivo mice cardiac tissue samples. Our system provides multiple advantages, in terms of improved scanning range, and reduced image acquisition time, which shows great potentials for three-dimensional biopsies of volumetric biological samples. 相似文献
455.
456.
Jay Vyas Ronald J Nowling Thomas Meusburger David Sargeant Krishna Kadaveru Michael R Gryk Vamsi Kundeti Sanguthevar Rajasekaran Martin R Schiller 《BMC bioinformatics》2010,11(1):328
Background
Minimotifs are short peptide sequences within one protein, which are recognized by other proteins or molecules. While there are now several minimotif databases, they are incomplete. There are reports of many minimotifs in the primary literature, which have yet to be annotated, while entirely novel minimotifs continue to be published on a weekly basis. Our recently proposed function and sequence syntax for minimotifs enables us to build a general tool that will facilitate structured annotation and management of minimotif data from the biomedical literature. 相似文献457.
K Plaut R Maple C Vyas S Munaim A Darling T Casey J R Alberts 《Proceedings of the Society for Experimental Biology and Medicine. Society for Experimental Biology and Medicine (New York, N.Y.)》1999,222(1):85-89
The effects of spaceflight on mammary metabolism of 10 pregnant rats was measured on Day 20 of pregnancy and after parturition. Rats were flown on the space shuttle from Day 11 through Day 20 of pregnancy. After their return to earth, glucose oxidation to carbon dioxide increased 43% (P < 0.05), and incorporation into fatty acids increased 300% (P < 0.005) compared to controls. It is unclear whether the enhanced glucose use is due to spaceflight or a response to landing. Casein mRNA and gross histology were not altered at Day 20 of pregnancy. Six rats gave birth (on Day 22 to 23 of pregnancy) and mammary metabolic activity was measured immediately postpartum. The earlier effects of spaceflight were no longer apparent. There was also no difference in expression of beta-casein mRNA. It is clear from these studies that spaceflight does not impair the normal development of the mammary gland, its ability to use glucose, nor the ability to express mRNA for a major milk protein. 相似文献