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21.
The genus Balcha Walker (Eupelmidae) is recorded for the first time in South Korea, with one newly described species and one newly recorded species. Both sexes of Balcha opaca Fusu sp. n. are described, and the presumed male of B. dictyota Gibson is described for the first time. The newly described species is peculiar in having a comparatively darker and less shiny mesoscutum. In other species of the genus the mesoscutum has brilliant metallic colours that contrast with dorsal dark bands along areas of much finer sculpture. 相似文献
22.
Elena Neagu Gabriel Lucian Radu Camelia Albu Gabriela Paun 《Saudi Journal of Biological Sciences》2018,25(3):578-585
In this study several investigations and tests were performed to determine the antioxidant activity and the acetylcholinesterase and tyrosinase inhibitory potential of Pulmonaria officinalis and Centarium umbellatum aqueous extracts (10% mass) and ethanolic extracts (10% mass and 70% ethanol), respectively. Moreover, for each type of the prepared extracts of P. officinalis and of C. umbellatum the content in the biologically active compounds – polyphenols, flavones and proanthocyanidins was determined. The antioxidant activity was assessed using two methods, namely the 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay and reducing power assay. The analyzed plant extracts showed a high acetylcholinesterase and tyrosinase inhibitory activity in the range of 72.24–94.24% (at the highest used dose – 3 mg/mL), 66.96% and 94.03% (at 3 mg/mL), respectively correlated with a high DPPH radical inhibition – 70.29–84.9% (at 3 mg/mL). These medicinal plants could provide a potential natural source of bioactive compounds and could be beneficial to the human health, especially in the neurodegenerative disorders and as sources of natural antioxidants in food industry. 相似文献
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24.
Davis JL Huang L Worodria W Masur H Cattamanchi A Huber C Miller C Conville PS Murray P Kovacs JA 《PloS one》2011,6(1):e16321
Background
Nucleic acid amplification tests are sensitive for identifying Mycobacterium tuberculosis in populations with positive sputum smears for acid-fast bacilli, but less sensitive in sputum-smear-negative populations. Few studies have evaluated the clinical impact of these tests in low-income countries with high burdens of TB and HIV.Methods
We prospectively enrolled 211 consecutive adults with cough ≥2 weeks and negative sputum smears at Mulago Hospital in Kampala, Uganda. We tested a single early-morning sputum specimen for Mycobacterium tuberculosis DNA using two nucleic acid amplification tests: a novel in-house polymerase chain reaction targeting the mycobacterial secA1 gene, and the commercial Amplified® Mycobacterium tuberculosis Direct (MTD) test (Gen-Probe Inc, San Diego, CA). We calculated the diagnostic accuracy of these index tests in reference to a primary microbiologic gold standard (positive mycobacterial culture of sputum or bronchoalveolar lavage fluid), and measured their likely clinical impact on additional tuberculosis cases detected among those not prescribed initial TB treatment.Results
Of 211 patients enrolled, 170 (81%) were HIV-seropositive, with median CD4+ T-cell count 78 cells/µL (interquartile range 29-203). Among HIV-seropositive patients, 94 (55%) reported taking co-trimoxazole prophylaxis and 29 (17%) reported taking antiretroviral therapy. Seventy-five patients (36%) had culture-confirmed TB. Sensitivity of MTD was 39% (95% CI 28–51) and that of secA1 was 24% (95% CI 15–35). Both tests had specificities of 95% (95% CI 90–98). The MTD test correctly identified 18 (24%) TB patients not treated at discharge and led to a 72% relative increase in the smear-negative case detection rate.Conclusions
The secA1 and MTD nucleic acid amplification tests had moderate sensitivity and high specificity for TB in a predominantly HIV-seropositive population with negative sputum smears. Although newer, more sensitive nucleic acid assays may enhance detection of Mycobacterium tuberculosis in sputum, even currently available tests can provide substantial clinical impact in smear-negative populations. 相似文献25.
Beatrice Brembilla-Perrot Pierre Yves Zinzius Laurent Groben Luc Freysz Lucian Muresan Jerome Schwartz Raphael P Martins Soumaya Jarmouni Ibrahim Nossier Nicolas Sadoul Hugues Blangy Arnaud Terrier De La Chaise Pierre Louis Olivier Selton Daniel Beurrier Jean Marc Sellal 《Indian pacing and electrophysiology journal》2010,10(4):162-172
Background
The results of programmed ventricular stimulation (PVS) may change after myocardial infarction (MI). The objective was to study the factors that could predict the results of a second PVS.Methods
Left ventricular ejection fraction (LVEF) and QRS duration were determined and PVS performed within 3 to 14 years of one another (mean 7.5±5) in 50 patients studied systematically between 1 and 3 months after acute MI.Results
QRS duration increased from 120±23 ms to 132±29 (p 0.04). LVEF did not decrease significantly (36±12 % vs 37±13 %). Ventricular tachycardia with cycle length (CL) > 220ms (VT) was induced in 11 patients at PVS 1, who had inducible VT with a CL > 220 ms (8) or < 220 ms (ventricular flutter, VFl) (3) at PVS 2. VFl or fibrillation (VF) was induced in 14 patients at PVS 1 and remained inducible in 5; 5 patients had inducible VT and 4 had a negative 2nd PVS. 2. 25 patients had initially negative PVS; 7 had secondarily inducible VT, 4 a VFl/VF, 14 a negative PVS. Changes of PVS were related to initially increasing QRS duration and secondarily changes in LVEF and revascularization but not to the number of extrastimuli required to induce VFl.Conclusions
In patients without induced VT at first study, changes of PVS are possible during the life. Patients with initially long QRS duration and those who developed decreased LVEF are more at risk to have inducible monomorphic VT at 2nd study, than other patients. 相似文献26.
Huang YT Lin X Chirieac LR McGovern R Wain JC Heist RS Skaug V Zienolddiny S Haugen A Su L Christiani DC 《PloS one》2011,6(8):e22961
Lung cancer, of which more than 80% is non-small cell, is the leading cause of cancer-related death in the United States. Copy number alterations (CNAs) in lung cancer have been shown to be positionally clustered in certain genomic regions. However, it remains unclear whether genes with copy number changes are functionally clustered. Using a dense single nucleotide polymorphism array, we performed genome-wide copy number analyses of a large collection of non-small cell lung tumors (n = 301). We proposed a formal statistical test for CNAs between different groups (e.g., non-involved lung vs. tumors, early vs. late stage tumors). We also customized the gene set enrichment analysis (GSEA) algorithm to investigate the overrepresentation of genes with CNAs in predefined biological pathways and gene sets (i.e., functional clustering). We found that CNAs events increase substantially from germline, early stage to late stage tumor. In addition to genomic position, CNAs tend to occur away from the gene locations, especially in germline, non-involved tissue and early stage tumors. Such tendency decreases from germline to early stage and then to late stage tumors, suggesting a relaxation of selection during tumor progression. Furthermore, genes with CNAs in non-small cell lung tumors were enriched in certain gene sets and biological pathways that play crucial roles in oncogenesis and cancer progression, demonstrating the functional aspect of CNAs in the context of biological pathways that were overlooked previously. We conclude that CNAs increase with disease progression and CNAs are both positionally and functionally clustered. The potential functional capabilities acquired via CNAs may be sufficient for normal cells to transform into malignant cells. 相似文献
27.
Many studies of lignins in solution invoke association and aggregation phenomena to explain their solution behavior (e.g., reprecipitation onto pulp fibers, condensation, etc.). Following their colloidal (apparent) molecular weights in solution as a function of time allows us to explore observable dissociation phenomena. These measurements were carried out using multiple angle laser light scattering (MALLS) photometry in the static mode. The challenges and opportunities of measuring the specific refractive index increment (dn/dC) of lignin solutions and determining the kinetics of the dissociation process were thus investigated. Hardwood and softwood representative lignins were isolated, and method for their full dissolution in THF was further developed, which then lead to accurate dn/dC values being obtained as a function of time. When coupled to additional work using light scattering static measurements and Zimm plots for the same solutions, this effort offers insight into the aggregation and ensuing dissociative events that operate within the lignin macromolecules. 相似文献
28.
Caraş I Tucureanu C Lerescu L Sălăgeanu A 《Roumanian archives of microbiology and immunology》2007,66(1-2):5-9
Dendritic cells (DCs) play a pivotal role in linking innate and adaptive immunity. Migration to the lymph nodes and maturation of DCs are crucial steps in the initiation of specific immune responses. The bacterial product CANTASTIM (CS) is a purified extract of Pseudomonas aeruginosa that induces non-specific protection against bacterial infection, enhances macrophage effector functions and modulates cytokines production. In this study, we used a mouse skin explant culture model and human monocyte-derived DCs to study the effect of CS on the migration and maturation of DCs, respectively. We noticed a significant increase in the number of DCs which migrated from the skin explants when CS was added to the culture medium. Also, CS was able to induce the expression of maturation-associated marker CD83 on human monocyte-derived DCs. DC-based tumor vaccines represent a promising approach for cancer immunotherapy and the migration rate and maturation state of DCs are important parameters for their clinical effectiveness. CS may be an attractive candidate to be tested for the production of DC-based vaccine. 相似文献
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30.
One of the most widely used animal models of Parkinson’s disease (PD) involves injecting 6-hydroxydopamine (6-OHDA) directly
into the substantia nigra (SN). Some recent reports speculated that dopaminergic drugs may exert brain antioxidant activity,
which could explain some of their protective actions. In this way, the aim of the present study was to examine the effects
of low-dose pergolide on memory deficits and brain oxidative stress in a 6-OHDA-induced rat model of PD. Right-unilateral
lesions of the SN were produced with 6-OHDA. Two weeks after neurosurgery, pergolide (0.3 mg/kg/day) was injected intraperitoneally
in the 6-OHDA + pergolide and sham-operated + pergolide groups, while sham-operated and 6-OHDA alone groups received saline.
Radial-8-arm maze and Y-maze were used for memory assessment. We also determined some enzymatic antioxidant defenses like
superoxide dismutase or glutathione peroxidase and a lipid peroxidation marker [malondialdehyde (MDA)], from the temporal
lobe. A reduced number of working/reference memory errors was observed in 6-OHDA + pergolide group, compared to sham-operated
rats. Additionally, post hoc analysis showed significant differences between 6-OHDA and 6-OHDA + pergolide groups in both
Y-maze and radial-arm-maze tasks. We also noted a significant decrease of MDA level in the 6-OHDA + pergolide group, compared
to sham-operated rats. Significant correlations were also found between behavioral parameters and MDA levels. Our data suggest
that pergolide facilitates spatial memory and improves brain oxidative balance, after a 6-OHDA-induced model of PD. This could
be useful for further investigations and clinical applications of pergolide. 相似文献