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991.
Atrasheuskaya AV Blatun EM Kulak MV Atrasheuskaya A Karpov IA Rubin S Ignatyev GM 《Vaccine》2007,25(24):4651-4658
The purpose of this study was to investigate mumps vaccine failures (VF) in a highly vaccinated population of Minsk, Belarus, and to investigate a possible role for virus strain-specific immunity. During our 3-year study period, 22 adults were admitted to the Infectious Diseases Hospital in Minsk with a diagnosis of mumps. A genotype H1 mumps virus (MuV) strain was identified in all patients. Of 15 patients from whom the paired sera were collected, 9 were confirmed to have been previously vaccinated. Serological examinations indicated primary VF in seven of these cases and secondary VF in two. Despite almost all vaccinated patients possessing MuV specific IgG, few possessed neutralizing antibody to the vaccine strain and titers were nominal. Importantly, none of the sera were able to neutralize a genotype H MuV strain. Our results demonstrate the importance of assaying for neutralizing antibody and support the assertion that antigenic differences between wild type and vaccine MuV strains may play a role in cases of breakthrough infection in vaccinees. 相似文献
992.
Cross-frequency phase-amplitude coupling (PAC) in neuronal oscillations network plays an important functional role in large scale neuronal communication and neuronal encoding. In the present study, a novel approach named permutation mutual information (PMI) was applied in measuring PAC. It is derived from the permutation entropy based on the mutual information theory, by which the mutual information of permutations of two time series can be evaluated. In order to verify the ability of PMI, a numerical test was performed by using both simulation data and experimental data. The performances of PMI were compared with that of two well-known methods, which were the mean vector length (MVL) and the modulation index (MI). It was found that the performance of PMI was similar to that of MI when measuring PAC intensity, but the coupling sensitivity of PMI was the highest among all these three approaches. Moreover, there was the lowest sensitivity in the MVL measurement, suggesting that MVL was a more conservative approach in detecting the existence of PAC. In addition, an ROC analysis showed that PMI performed better in measuring PAC compared to that of others. Furthermore, the experimental data, obtained from rats’ hippocampal CA3 regions, were analyzed by using the three approaches. The result was essentially in line with that of the simulation performances. In a word, the results suggest that PMI is a better choice for assessing PAC under the certain conditions. 相似文献
993.
Veeraswamy RK Rubin BG Sanchez LA Curi MA Geraghty PJ Parodi JC Sicard GA 《Perspectives in vascular surgery and endovascular therapy》2007,19(4):403-408
Procedure-related complications with carotid artery stenting must be minimized for it to be a valid treatment for carotid stenosis. Failure analysis was done for 207 carotid stent procedures. All complications were reviewed and technical errors were identified. The procedure-related stroke rate was 2.9%, technical failure rate was 1.9%, and no patients died. Two strokes resulted from protocol deviations. A third stroke occurred while crossing a long, irregular lesion with a protection device instead of establishing flow reversal. Excessive instrumentation of the aortic arch resulted in 2 strokes. Distal embolization occurred after open-cell stenting a friable lesion in 1 patient. The majority of neurologic events and technical complications that occur during carotid stenting are preventable. By adhering to technical protocols, avoiding excessive instrumentation in the aortic arch, using flow reversal in selected lesions, and matching the appropriate anatomy and stent, results of carotid artery stenting can be exceptional. 相似文献
994.
BACKGROUND: Many patients with type 2 diabetes mellitus (DM) with inadequate long-term blood glucose control with sulfonylurea or metformin monotherapy require additional treatment. The synergistic effects of combining glipizide with metformin on glucose control may be realized by treating the primary effects of type 2 DM, impaired insulin secretion, and insulin resistance. OBJECTIVE: This study assessed therapy with glipizide/metformin combination tablets in patients with type 2 DM that is uncontrolled by at least half the maximum labeled daily dose of a sulfonylurea. METHODS: In this multicenter, double-masked, parallel-group, active-controlled study, patients were randomized to receive glipizide 30-mg, metformin 500-mg, or glipizide/metformin 5/500 mg tablets for 18 weeks (metformin and glipizide/metformin doses were titrated to achieve blood glucose control). Maximum total daily doses were glipizide 30 mg, metformin 2000 mg, and glipizide/ metformin 20/2000 mg. RESULTS: A total of 247 patients were included in the study. The mean (SD) age was 56.2 (10.1) years; 61.5% of patients were male; 70.0% were white, 15.8% were Hispanic/Latino, 13.0% were black, and 1.2% were Asian/Pacific Islanders. Patients were, on average, obese (mean [SD] body mass index, 31.3 [4.7] kg/m2), had moderate to severe hyperglycemia (mean [SD] glycated hemoglobin [HbA1c], 8.7% [1.1]), and had a mean (SD) DM duration of 6.5 (4.9) years. Glipizide/ metformin tablets controlled the HbA1c level more effectively than did either glipizide or metformin monotherapies (mean treatment differences, in favor of glipizide/ metformin, of -1.06% and -0.98%, respectively, P < 0.001). At study end, an HbA1c level < 7.0% was achieved in approximately 4-fold more patients who were treated with glipizide/metformin (36.3%) compared with glipizide (8.9%) or metformin (9.9%) monotherapies. Glipizide/metformin tablets also reduced the fasting plasma glucose (FPG) level and the 3-hour postprandial glucose area under the concentration-time curve more effectively than did either monotherapy, without increasing the fasting insulin level. The greater blood glucose control with glipizide/ metformin tablets was achieved at a mean daily dose of glipizide/metformin 17.5/1747 mg, compared with mean doses of glipizide 30.0 mg or metformin 1927 mg. Treatments were well tolerated, with a low incidence of symptoms of hypoglycemia evidenced by a fingerstick blood glucose measurement < or = 50 mg/dL in the combination group (12.6%); 1 patient discontinued the study treatment for this reason. No patient required medical assistance for hypoglycemia. CONCLUSIONS: Glipizide/metformin tablets were more effective than either glipizide or metformin monotherapy in controlling HbA1c and in reducing FPG compared with baseline in patients with blood glucose that was uncontrolled with previous sulfonylurea treatment. In addition, patients receiving glipizide/ metformin were more likely to achieve an HbA1c level < 7.0%. These results were consistent with the synergistic effects on insulin resistance and beta cell dysfunction. Glipizide/metformin was well tolerated, with a low incidence of hypoglycemia. 相似文献
995.
This report describes how a rehabilitation team treats dizziness and vestibular disorders. Team members include a nurse, physician, audiologist, physical therapist, occupational therapist, and a research scientist. Although unusual, this multidisciplinary approach, involving a close-knit group of professionals, is of great benefit in the treatment of vestibular and balance disorders. 相似文献
996.
H S Wisoff G B Jacobs R C Rubin J H Hubbard R L Wille 《Journal of neurosurgical nursing》1979,11(1):16-20
Spinal AVM's are not rare, and are diagnosed today with increasing frequency by utilization of moedern neuroradiological techniques. Their relationship to the spinal medulla is related to vascular embryological anatomy, and the only effective treatment is directed at obliteration of the fistula. Males are affected more frequently in the middle years of life. Symptoms may mimic spinal cord tumors and demyelinating disorders. The pathogenesis of symptoms, classification, and methods of diagnosis are reviewed, and the various methods of treatment discussed. 相似文献
997.
Vileikyte L Leventhal H Gonzalez JS Peyrot M Rubin RR Ulbrecht JS Garrow A Waterman C Cavanagh PR Boulton AJ 《Diabetes care》2005,28(10):2378-2383
OBJECTIVE: We examined the association between severity of diabetic peripheral neuropathy and depressive symptoms and investigated the potential mediators of this association. RESEARCH DESIGN AND METHODS: The Hospital Anxiety and Depression Scale (HADS) was used to assess depressive symptoms in 494 patients (mean age 62 years; 70% male; 72% type 2 diabetic) with diabetic neuropathy diagnosed by the Neuropathy Disability Score (NDS) and the Vibration Perception Threshold (VPT). Diabetic neuropathy symptoms, activities of daily living (ADLs), and social self-perception were measured by the neuropathy and foot ulcer-specific quality-of-life instrument, NeuroQoL; perceptions of diabetic neuropathy symptom unpredictability and the lack of effective treatment were assessed by the revised Illness Perception Questionnaire. RESULTS: Both the NDS and VPT were significantly associated with the HADS after controlling for demographic and disease variables. Although diabetic neuropathy symptoms mediated this association, with unsteadiness being most strongly associated with HADS, the relationship between foot ulceration and depression was nonsignificant. The association between diabetic neuropathy symptoms and HADS was partially mediated by two sets of psychosocial variables: 1) perceptions of diabetic neuropathy symptom unpredictability and the lack of treatment control and 2) restrictions in ADLs and changes in social self-perception. CONCLUSIONS: These findings establish the association between diabetic neuropathy and depressive symptoms and identify potential targets for interventions to alleviate depressive symptoms in persons affected by diabetic peripheral neuropathy. 相似文献
998.
Cloning of a cDNA encoding the rat high molecular weight neurofilament peptide (NF-H): developmental and tissue expression in the rat, and mapping of its human homologue to chromosomes 1 and 22. 总被引:5,自引:1,他引:5 下载免费PDF全文
999.
Papasani MR Gensure RC Yan YL Gunes Y Postlethwait JH Ponugoti B John MR Jüppner H Rubin DA 《Endocrinology》2004,145(11):5294-5304
Although the PTH type 2 receptor (PTH2R) has been isolated from mammals and zebrafish, only its mammalian agonist, tuberoinfundibular peptide 39 (TIP39), has been characterized thus far. To determine whether zebrafish TIP39 (zTIP39) functions similarly with the zebrafish PTHR (zPTH2R) and human PTH2Rs and to determine its tissue-specific expression, fugu (Takifugu rubripes) and zebrafish (Danio rerio) genomic databases were screened with human TIP39 (hTIP39) sequences. A single TIP39 gene was identified for each fish species, which showed significant homology to mammalian TIP39. Using standard molecular techniques, we isolated cDNA sequences encoding zTIP39. The fugu TIP39 precursor was encoded by a gene comprising at least three exons. It contained a hydrophobic signal sequence and a predicted prosequence with a dibasic cleavage site, similar to that found in mammalian TIP39 ligands. Phylogenetic analyses suggested that TIP39 forms the basal group from which PTH and PTHrP have been derived. Functionally, subtle differences in potency could be discerned between hTIP39 and zTIP39. The human PTH2R and zPTH2R were stimulated slightly better by both hTIP39 and zTIP39, whereas zTIP39 had a higher potency at a previously isolated zPTH2R splice variant. Whole-mount in situ hybridization of zebrafish revealed strong zTIP39 expression in the region of the hypothalamus and in the heart of 24- and 48-h-old embryos. Similarly, zPTH2R expression was highly expressed throughout the brain of 48- and 72-h-old embryos. Because the mammalian PTH2R was also most abundantly expressed in these tissues, the TIP39-PTH2R system may serve conserved physiological roles in mammals and fishes. 相似文献
1000.
Ca2+ and phospholipid-dependent protein kinase (protein kinase C) activity is not necessarily required for secretion by human neutrophils 总被引:2,自引:0,他引:2
Ca2+-dependent and phospholipid-dependent protein kinase (PKC) is a receptor for and is activated by phorbol esters. This enzyme is reportedly involved in the mechanism of superoxide anion (O2-) production and the release of intracellular granule contents from human neutrophils. As previously reported by others, we found that greater than 75% of the total cellular PKC activity existed in a soluble form in untreated neutrophils and that this activity was enhanced in a dose- dependent manner by phorbol 12-myristate 13-acetate (PMA) and by phorbol 12,13-dibutyrate (PDBu). Furthermore, mezerein, an analogue of PMA that is thought to be a competitive inhibitor, did not activate PKC, and on the contrary, inhibited PMA-stimulated activity in a dose- dependent manner. Pretreatment of intact neutrophils with PMA or PDBu caused the "translocation" of PKC activity to the insoluble cell fraction; PKC translocation was not detected after mezerein stimulation at any of the tested concentrations. Neither did mezerein cause an increase in intracellular Ca2+, as monitored by Quin 2 fluorescence. Both phorbol esters and mezerein stimulated intact neutrophils to generate O2- and release lysosomal enzymes into the extracellular medium. Finally sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) analysis demonstrated key differences in the patterns of endogenous phosphoproteins of neutrophils stimulated with phorbol as compared with mezerein. We therefore suggest that PKC activation may not be the only pathway required to elicit neutrophil responses. 相似文献