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11.
Comparison of antibody repertoires against Staphylococcus aureus in healthy individuals and in acutely infected patients 总被引:1,自引:0,他引:1
Dryla A Prustomersky S Gelbmann D Hanner M Bettinger E Kocsis B Kustos T Henics T Meinke A Nagy E 《Clinical and diagnostic laboratory immunology》2005,12(3):387-398
The management of staphylococcal diseases is increasingly difficult with present medical approaches. Preventive and therapeutic vaccination is considered to be a promising alternative; however, little is known about immune correlates of protection and disease susceptibility. To better understand the immune recognition of Staphylococcus aureus by the human host, we studied the antistaphylococcal humoral responses in healthy people in comparison to those of patients with invasive diseases. In a series of enzyme-linked immunosorbent assay analyses performed using 19 recombinant staphylococcal cell surface and secreted proteins, we measured a wide range of antibody levels, finding a pronounced heterogeneity among individuals in both donor groups. The analysis revealed marked differences in the antibody repertoires of healthy individuals with or without S. aureus carriage, as well as in those of patients in the acute phase of infection. Most importantly, we identified antigenic proteins for which specific antibodies were missing or underrepresented in infected patients. In contrast to the well-described transient nature of disease-induced antistaphylococcal immune response, it was demonstrated that high-titer antistaphylococcal antibodies are stable for years in healthy individuals. In addition, we provide evidence obtained on the basis of opsonophagocytic and neutralizing activity in vitro assays that circulating antistaphylococcal serum antibodies in healthy donors are functional. In light of these data we suggest that proper serological analysis comparing the preexisting antibody repertoires of hospitalized patients with different outcomes for nosocomial staphylococcal infections could be extremely useful for the evaluation of candidate vaccine antigens in addition to protection data generated with animal models. 相似文献
12.
Results from recent studies have shown that alpha(1A)-adrenergic receptor (alpha(1A)-AR) antagonists could offer a new alternative in the treatment of preterm delivery. However, members of this group [2-(2,6-dimethoxyphenoxyethyl)aminomethyl-1,4-benzodioxane hydrochloride (WB4101), 5-methylurapidil (5-MU)] are known to influence serotonin (5-hydroxy-tryptamine) (5-HT(1A)) receptors, too. Our objective was to clarify the role of their 5-HT(1A) activities in the uterus relaxant effect. RT-PCR was used to determine mRNA expression of the receptor subtypes in 22 day pregnant rat uteri. Isolated uteri were stimulated by 5-HT or electrical field to investigate the contraction-inhibiting effect and the 5-HT(1A) activity of the alpha(1A) antagonists. Both receptor subtypes are present in rat myometrium. 5-HT induced contractions were inhibited by the alpha(1A) antagonists. Besides shifting the dose-response curve of 5-HT to the right, 5-MU decreased its maximal effect. The alpha(1A) antagonists inhibited electrical field stimulation-induced contractions. 5-HT(1A) blockade increased the maximal effect of 5-MU but did not change that of WB4101. These results suggest that the contraction increase caused by 5-HT is mediated by alpha(1A) receptors. Serotonergic activity of alpha(1) antagonists and especially alpha(1A) antagonists should be investigated as it may alter their efficacy and could interfere with their side-effects. It is proposed that novel alpha(1A) antagonists should be designed with no 5-HT(1A) activity to achieve maximal relaxant effect. 相似文献
13.
The Schizosaccharomyces pombe rad51+ and dmc1+ genes code for homologues of the Escherichia coli recombination protein RecA. Deletion of rad51+ causes slow growth, retardation of cell division and a decrease in viability. rad51 cells have a defect in mating-type switching. The DNA modification at the mating-type locus required for mating-type switching contributes to slow growth in the rad51 mutant. Cell mating is reduced in crosses homozygous for rad51. Ectopic expression of the dmc1+ gene allowed us to demonstrate that the reduction in meiotic recombination in dmc1 mutants is not caused by a disturbance of rad24 expression from the dmc1-rad24 bicistronic RNA. We describe the functional defects of terminally epitope-tagged Dmc1 and Rad51 and discuss it in terms of protein interaction. Presumptive Rad51 and Dmc1 foci were detected on spreads of meiotic chromatin. 相似文献
14.
Interaction of plasma fibronectin (pFN) with membranous constituents of peritoneal exudate cells and pulmonary macrophages 总被引:2,自引:0,他引:2
The prominent role of plasma fibronectin (pFN) in the host defense system as an opsonin for gelatin (collagen)-coated colloids has been established. In the present study we investigated the interaction of pFN and membrane isolates from cells devoid of collagen, as well as several tissues. In a liver slice assay system it was shown that subcellular membrane fractions from lung macrophages, peritoneal exudate cells, spleen, tests, and liver were able to competitively inhibit the pFN-mediated uptake of 125I-gelatin coated latex beads (gLtx) at low concentrations. Endocytosis of 125I-labeled membrane isolates by macrophage monolayers was also promoted by addition of pFN. In an attempt to characterize the membrane component(s) interacting with pFN, it was found that mild extraction procedure with 1 M KBr could release a significant amount of this inhibitory activity. Further studies demonstrated that the agent(s) responsible for inhibition of gLtx uptake was heat sensitive, not altered by trypsin treatment, and did not contain actin, a protein known to interact with pFN. This work indicates that pFN interacts specifically with an as yet unknown membrane component(s) and that such interaction will promote clearance of cellular debris by macrophages. This suggests that pFN may be an important opsonin for the reticuloendothelial system in clearance of collagenous and noncollagenous cellular debris once they are exposed to interact with it. 相似文献
15.
V. I. Kulakov G. T. Molnar V. V. Malaitsev T. M. Bogdanova M. Yu. Sutyrin 《Bulletin of experimental biology and medicine》1994,117(4):411-414
The clinical applications of theoretical immunology are not numerous. The authors demonstrate present-day immunocytotherapeutic
approaches to fetal tissue transplantation widely used in medicine. Results of therapy by injections of lymphokine-activated
killer cells in combination with interleukin-2, T-cell vaccines, and genetically transformed T cells are presented.
Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 117, N
o
4, pp. 412–415, April, 1994 相似文献
16.
Simona Gurzu Tivadar Bara Calin Molnar Tivadar Bara Vlad Butiurca Hanga Beres Simin Savoji Ioan Jung 《Pathology, research and practice》2019,215(1):82-89
Background
Pancreatic mucinous cystic neoplasms (MCN) are rare tumors that are usually diagnosed in females.Materials and methods
In our department, only four of the 109 consecutive cases of pancreatic tumors (3.67%) were diagnosed as MCNs. In this report, we present the characteristics of these four specific cases which also showed unusual HER-2 positivity and neuroendocrine differentiation.Results
The four MCNs were diagnosed in patients with ages between 46 and 75 years. Other clinical particularities were the following: one benign case, splenic rupture as result of a giant cystic tumor on the tail of the pancreas directly invading the spleen in the second one, metastases in the accessory spleen in the third one and invasion of the abdominal vessels in the fourth case. In all of these cases, the ovarian-like stroma tested positivity for calretinin, progesterone receptor (PR) and, in cases 2 and 3, for AE1/AE3 keratin. The malignant tumor cells were marked by carcinoembryonic antigen, HER-2, maspin, PR and the neuroendocrine markers synaptophysin, CD56, and neuron-specific enolase.Conclusions
These cases highlight the unusually aggressive behavior of pancreatic MCN with invasive carcinomas that share mixed exo- and endocrine components and show epithelial-mesenchymal transition. 相似文献17.
The long-term objective is to understand how large masses of neurons in the brain process information during various learning and memory paradigms. Both time- and space-dependent processes have been identified in animals through computer-based analytic quantifications of event-related extracellular potentials. New nonlinear analyses have been introduced that presume that the fine-grain variation in the signal is determined and patterned in phase-space. Some neurons in the primary visual cortex manifest gamma-band oscillations. These cells show both a nonspecific phase-alignment (response synchrony) and a specific tuning (orientation tuning) when stimuli are presented to their receptive fields. This dual regulation of the sensory cells is proposed to underlie stimulus binding, a theoretical mechanism for "object" perception. Nonlinear analytic results from gamma-activities in a simple model neuropil (olfactory bulb) suggest that neuroplasticity may arise through self-organization, a process in which a nonlinear change in the dynamics of the oscillatory field potentials is the hallmark. This self-organization may follow simple dynamical laws in which global cooperativity among the neurons is transiently brought about that, over trials, results in enduring changes in the nonlinear dynamics of some neurons. In conclusion, the sculpturing of the synaptic throughput in the sensory cortex (stimulus binding) may be associated with the irregular phases of the gamma-activities and may result from both specific and nonspecific systems operating together in a nonlinear self-organizing manner. 相似文献
18.
Activation of group I and group II metabotropic glutamate receptors (mGluRs) is thought to be required for long-term depression (LTD) of alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionate (AMPA) receptor-mediated synaptic transmission in the perirhinal cortex. However, little is known about how activation of mGluRs leads to this form of synaptic plasticity. AMPA receptor phosphorylation has been implicated in several forms of modulation of synaptic transmission. In the CA1 area of the hippocampus, N-methyl-d-aspartate (NMDA) receptor-dependent LTD is associated with the reduced phosphorylation of the GluR1 AMPA receptor subunit at serine 845 (GluR1-S845). Immunoblot analysis of perirhinal cortical neurons using GluR1 and GluR1-S845 phosphorylation state specific antibodies showed that stimulation of adenylyl cyclase (AC) with forskolin (FSK) dramatically increased PKA-mediated phosphorylation of GluR1-S845. However, selective or simultaneous application of mGluR5 agonist (S)-3,5-dihydroxyphenylglycine (CHPG) and mGluR2/3 agonist (2S,2'R,3'R)-2-(2',3'-dicarboxycyclopropyl)glycine (DCG IV) did not produce detectable changes in GluR1-S845 phosphorylation. These results indicate that in the perirhinal cortex mGluR activation does not alter the phosphorylation state of GluR1-S845. Therefore, it is likely that the process involved in the modification of AMPA receptors in mGluR activation dependent LTD in the perirhinal cortex is mechanistically distinct from NMDA receptor-mediated LTD described in hippocampal neurons. 相似文献
19.
Tarek Alhamad Michelle Lubetzky Krista L. Lentine Emmanuel Edusei Ronald Parsons Martha Pavlakis Kenneth J. Woodside Deborah Adey Christopher D. Blosser Beatrice P. Concepcion John Friedewald Alexander Wiseman Neeraj Singh Su-Hsin Chang Gaurav Gupta Miklos Z. Molnar Arpita Basu Edward Kraus Song Ong Arman Faravardeh Ekamol Tantisattamo Leonardo Riella Jim Rice Darshana M. Dadhania 《American journal of transplantation》2021,21(9):3034-3042
Kidney allograft failure and return to dialysis carry a high risk of morbidity. A practice survey was developed by the AST Kidney Pancreas Community of Practice workgroup and distributed electronically to the AST members. There were 104 respondents who represented 92 kidney transplant centers. Most survey respondents were transplant nephrologists at academic centers. The most common approach to immunosuppression management was to withdraw the antimetabolite first (73%), while only 12% responded they would withdraw calcineurin inhibitor (CNI) first. More than 60% reported that the availability of a living donor is the most important factor in their decision to taper immunosuppression, followed by risk of infection, risk of sensitization, frailty, and side effects of medications. More than half of respondents reported that embolization was either not available or offered to less than 10% as an option for surgical intervention. Majority reported that ≤50% of failed allograft patients were re-listed before dialysis, and less than a quarter of transplant nephrologists performed frequent visits with their patients with failed kidney allograft after they return to dialysis. This survey demonstrates heterogeneity in the care of patients with a failing allograft and the need for more evidence to guide improvements in clinical practice related to transition of care. 相似文献
20.
Examination of the causes of late mortality in multiple trauma patients reveals that as much as 78% of all deaths may be attributed to septic complications, suggesting the value of understanding the prevention and treatment of traumatic sepsis. In penetrating trauma, the protective features of the skin are eliminated, and systemic mechanisms of host defense are compromised. These changes in the host defense mechanism and the risk of infection influence the choice and technical features of wound closure and the use of antibiotics. Early diagnosis is imperative, but difficult. 相似文献