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91.
The molluscicidal activity of crushed seed pods of Swartzia madagascariensis was assessed by laboratory and field trials. Mature dry seed pods were ground and extracted in tap water for 24 h. Water extracts exerted a significant molluscicidal activity against Bulinus globosus up to dilutions of 100 mg of ground pods per litre. The chromatographically isolated saponin (1) responsible for the molluscicidal activity showed a toxicity of LC 100 at 3 mg/l after exposure of B. globosus and Biomphalaria glabrata for 24 h. Saponin (1) could be identified by FAB-MS and 13C-NMR-spectroscopy as oleanolic acid-3-O-beta-D-glucuronopyranosyl (1----3)-alpha-L-rhamnopyranoside. Two field trials with S. madagascariensis pod extracts in ponds (60 and 160 m3) harbouring dense populations of B. globosus compared well with the laboratory findings and showed the efficiency of the molluscicide in a natural habitat. A single application of the plant molluscicide significantly reduced the populations of B. globusus. The toxicity of S. madagascariensis pod extracts to non-target organisms remains an obstacle for its use in certain situations where schistosomiasis control is envisaged and where S. madagascariensis is found. However, S. madagascariensis is a valid candidate molluscicide which may be applied in selected epidemiological settings as part of integrated schistosomiasis control measures.  相似文献   
92.
Schizosaccharomyces pombe cells were transformed with an S. pombe expression vector containing a full-length cDNA of the Chlorella hexose transporter. The transformed cells accumulated 3-O-methylglucose up to 10-fold, whereas wild-type S. pombe and control transformants could only equilibrate this sugar analogue. In a pH-jump experiment, in which extracellular pH was lowered by 1.9 units, the accumulation ratio was increased in transformed cells but not in control cells. This result indicates that the gene product, Chlorella H+/glucose-symporter protein, and a pH gradient suffice for active sugar uptake. Km values for glucose, 6-deoxyglucose, and 3-O-methylglucose of 1.5 x 10(-5) M, 2.7 x 10(-4) M, and 1.0 x 10(-3) M, respectively, were identical in Chlorella and in S. pombe cells transformed with Chlorella cDNA and approximately 100-fold lower than those of the endogenous transport system of S. pombe.  相似文献   
93.
The prevalence of antibodies to human immunodeficiency virus (HIV = LAV/HTLV-III) in a rural population from the Ifakara area in southeastern Tanzania was investigated. Sera from 286 individuals collected from 1982 to 1984 in connection with a study on liver disorders were tested by an ELISA. Fifty-two (18.2%) of the sera were found positive. While the positives were largely confirmed by one commercial ELISA, they were completely negative by two others. Confirmatory testing by Western blot and competition Western blot showed that the reactivity detected by more sensitive of these assays was largely due to IgG antibodies binding to the HIV core (gag) proteins p17, its precursor p55 and, in some cases, p24. These tests also indicated, however, that the reactive antibodies could not have been elicited by HIV, but possibly by an unknown retrovirus or another cross-reactive agent. Thus, by 1984, the area investigated was largely free of HIV infection, but a significant proportion of its population may harbor another retrovirus of unknown pathogenicity.  相似文献   
94.
95.
PurposeTo determine the reliability of subjective and objective quantification of mitral annular calcification (MAC) in elderly patients with severe aortic stenosis, to define quantitative sex- and age-related reference values of MAC, and to correlate quantitative MAC with mitral valve disease.MethodsIn this retrospective, IRB-approved study, we included 559 patients (268 females, median age 81 years, inter-quartile range 77–85 years) with severe aortic stenosis undergoing CT. Four independent readers performed subjective MAC categorization as follows: no, mild, moderate, and severe MAC. Two independent readers performed quantitative evaluation of MAC using the Agatston score method (AgatstonMAC). Mitral valve disease was determined by echocardiography.ResultsSubjective MAC categorization showed high inter-reader agreement for no (k ?= ?0.88) and severe MAC (k ?= ?0.75), whereas agreement for moderate (k ?= ?0.59) and mild (k ?= ?0.45) MAC was moderate. Intra-reader agreement for subjective MAC categorization was substantial (k ?= ?0.69 and 0.62). Inter- and intra-reader agreement for AgatstonMAC were excellent (ICC ?= ?0.998 and 0.999, respectively), with minor inconsistencies in MAC involving the left ventricular outflow tract/aortic valve. There were significantly more women than men with MAC (n ?= ?227, 85% versus n ?= ?209, 72%; p ?< ?0.001), with a significantly higher AgatstonMAC (median 597, range 81–2055 versus median 244; range 0–1565; p ?< ?0.001), particularly in patients ≥85 years of age. AgatstonMAC showed an area-under-the-curve of 0.84 to diagnose mitral stenosis, whereas there was no association of AgatstonMAC with mitral regurgitation (p ?> ?0.05).ConclusionsOur study in elderly patients with severe aortic stenosis shows that quantitative MAC scoring is more reliable than subjective MAC assessment. Women show higher AgatstonMAC scores than men, particularly in the elderly population. AgatstonMAC shows high accuracy to diagnose mitral stenosis.  相似文献   
96.
Psychostimulant use disorder is a major public health issue, and despite the scope of the problem there are currently no Food and Drug Administration (FDA)-approved treatments. There would be tremendous utility in development of a treatment that could help patients both achieve and maintain abstinence. Previous work from our group has identified granulocyte-colony stimulating factor (G-CSF) as a neuroactive cytokine that alters behavioral response to cocaine, increases synaptic dopamine release, and enhances cognitive flexibility. Here, we investigate the role of G-CSF in affecting extinction and reinstatement of cocaine-seeking and perform detailed characterization of its proteomic effects in multiple limbic substructures. Male Sprague Dawley rats were injected with PBS or G-CSF during (1) extinction or (2) abstinence from cocaine self-administration, and drug seeking behavior was measured. Quantitative assessment of changes in the proteomic landscape in the nucleus accumbens (NAc) and medial prefrontal cortex (mPFC) were performed via data-independent acquisition (DIA) mass spectrometry analysis. Administration of G-CSF during extinction accelerated the rate of extinction, and administration during abstinence attenuated cue-induced cocaine-seeking. Analysis of global protein expression demonstrated that G-CSF regulated proteins primarily in mPFC that are critical to glutamate signaling and synapse maintenance. Taken together, these findings support G-CSF as a viable translational research target with the potential to reduce drug craving or seeking behaviors. Importantly, recombinant G-CSF exists as an FDA-approved medication which may facilitate rapid clinical translation. Additionally, using cutting-edge multiregion discovery proteomics analyses, these studies identify a novel mechanism underlying G-CSF effects on behavioral plasticity.SIGNIFICANCE STATEMENT Pharmacological treatments for psychostimulant use disorder are desperately needed, especially given the disease''s chronic, relapsing nature. However, there are currently no Food and Drug Administration (FDA)-approved pharmacotherapies. Emerging evidence suggests that targeting the immune system may be a viable translational research strategy; preclinical studies have found that the neuroactive cytokine granulocyte-colony stimulating factor (G-CSF) alters cocaine reward and reinforcement and can enhance cognitive flexibility. Given this basis of evidence we studied the effects of G-CSF treatment on extinction and reinstatement of cocaine seeking. We find that administration of G-CSF accelerates extinction and reduces cue-induced drug seeking after cocaine self-administration. In addition, G-CSF leads to downregulation of synaptic glutamatergic proteins in medial prefrontal cortex (mPFC), suggesting that G-CSF influences drug seeking via glutamatergic mechanisms.  相似文献   
97.

Compelling evidence exists that non-Hispanic blacks (NHB) engage in pain catastrophizing (negatively evaluate one’s ability to cope with pain) more often than non-Hispanic whites (NHW). Functional neuroimaging studies revealed that individuals with high levels of trait pain catastrophizing show increased cerebral responses to pain in several pain-related brain regions (e.g., insula, primary somatosensory cortex [S1]), but associations between brain structure and catastrophizing remain largely unexplored. The current investigation was conducted at the University of Florida and the University of Alabama at Birmingham. Participants were 129 community-dwelling adults with or at risk of knee osteoarthritis (OA). Participants completed the pain catastrophizing subscale of the Coping Strategies Questionnaire-Revised and the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain intensity subscale. Magnetic Resonance Imaging data were obtained. MANOVA and Chi-Square analyses assessed sociodemographic/clinical differences stratified by ethnicity/race. Multivariate regression analyses with insula and somatosensory cortical thickness entered as dependent variables with catastrophizing and the interaction between catastrophizing and ethnicity/race as the independent variables. Covariates include education, body mass index, study site, and WOMAC pain (ethnicity/race was an additional covariate in non-stratified analyses). There were significant interactions between ethnicity/race, pain catastrophizing, and brain structure. Higher pain catastrophizing was associated with thinner S1 bilaterally (ps < .05) in NHW, but not NHB participants with or at risk for knee OA. These results suggest that pain catastrophizing might have differing effects on pain-related central pathways and may contribute to ethnic/race group differences in individuals with or at risk for knee OA.

  相似文献   
98.
This clinical report details the rehabilitation of a patient who underwent a total rhinectomy, subsequent adjuvant radiation therapy, and eventual prosthetic rehabilitation but then developed an empirically diagnosed medical adhesive intolerance. With the aid of digital planning and real time navigation, 2 zygomatic implants were placed by using a flapless surgical approach followed by early delivery of an interim prosthesis. In spite of the failure of 1 craniofacial implant, definitive restoration was accomplished by using a titanium bar, double magnetic attachments, and a new silicone prosthesis.  相似文献   
99.
100.
ObjectiveThis meta-evaluation aimed to summarize all available evidence regarding different fissure sealants on occlusal caries prevention, arrest, retention rate, adverse effect, and cost-effectiveness; when compared with no intervention, other preventive or minimally-invasive procedures.Materials and MethodsThe systematic reviews and meta-analyses were identified via four electronic databases and manual searching. Two independent reviewers performed study selection, data extraction, quality assessment with AMSTAR-2.ResultsAmong the 366 records yielded, 38 systematic reviews were identified as eligible 24 of them included meta-analyses. Moderate evidence has supported the efficacies of resin-based sealants (RBS) in occlusal caries prevention, arrest and cost-effectiveness compared to no interventions. Low to very low certainty of evidence suggested similar effectiveness of glass-ionomer cements in caries prevention with RBS and more superior performance of resin infiltration in arresting non-cavitated occlusal lesions.ConclusionThis meta-evaluation supports the use of RBS on permanent molars to reduce occlusal caries occurrence, arrest lesion progression and alleviate oral health inequalities between individuals of different socioeconomic status. This meta-evaluation also advocates further research on glass-ionomer cements and resin infiltration with respect to their efficacies in caries prevention and arrest.  相似文献   
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