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91.
The antimicrobial activity of a methanol extract and isolated constituents of Mitracarpus scaber, a species used in folk medicine by West African native people, was evaluated against Staphylococcus aureus and Candida albicans strains. The mitracarpus methanol extract possesses both antibacterial and antimycotic activities (minimum inhibitory concentration-MIC 31.25 and 62.50 microg ml-, respectively). This extract was subsequently fractioned and monitored by bioassays leading to the isolation of seven compounds screened for antibacterial and antimycotic activities. Among these compounds, gallic acid and 3,4,5-trimethoxybenzoic acid inhibited the growth of Staph. aureus (MIC 3.90 and 0.97 microg ml-). 4-Methoxyacetophenone and 3,4,5-trimethoxyacetophenone effectively inhibited C. albicans (MIC 1.95 microg ml-). The other compounds (kaempferol-3-O-rutinoside, rutin and psoralen) which were also isolated showed low antibacterial and antimycotic activities (125-500 microg ml-).  相似文献   
92.
More than 30 years after its introduction, growth hormone (GH) treatment is well established in children with GH deficiency. Nevertheless, the long-term results of this therapy, expressed as height, are generally considered unsatisfactory. We report on results obtained in a group of GH-deficient children who were treated with daily injections of recombinant GH within the first 5 years of life and who reached an adult height very close to their target height. The full catch-up growth to the target height demonstrated in these patients suggests that replacement therapy should be started early and continued until adulthood. Height at onset of puberty is an important variable which might significantly influence the adult height. The significant and prolonged influence of birth weight on growth response to GH therapy underlines the important role of fetal growth in planning early treatment of GH-deficient children.  相似文献   
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AIDS pathogenesis results from a complex array of immune alterations which include, among others, changes in the pattern of cytokine production. Some monocyte-derived cytokines, like TNFalpha play a major role in HIV pathogenesis. TNFalpha transactivates HIV NF-kB thereby inducing viral replication, potentiates HIV replication in lymphomonocytes TNFalpha is one of the main factors of HIV-induced cachexia and might be involved in HAART-associated lipodystrophy. In addition, monocytes are infectable by HIV in vitro and infected monocytes can be recovered from the blood of HIV infected patients. For these reasons, we tested whether renewal of the pool of circulating monocytes by selective monocyte apheresis may improve the immune reconstitution which follows treatment with highly active anti-retrovirals (HAART). HIV-infected HAART receiving (> 1 year) patients who were either virologically non-responders (HIV-1 RNA >50,000 copies/ml) or immunologically non-responders (CD4 counts < 200) were treated with a novel monocyte apheresis device (G-1 Adacolumn). Plasma HIV viral load, proviral DNA and phenotypic and functional immunological analyses were performed. G-1 apheresis was well tolerated, not accompanied by adverse responses, and followed by clinical improvement. TNFalpha production was suppressed and CD4 T cell counts increased. In one G-1 patient with elevated HIV-1 proviral DNA a significant reduction (from 1,500 to 40 copies/10(5) cells) was observed. Neither immunologic nor virologic parameters were modified in the control patients who received HAART alone. Thus, purging of circulating monocytes by G-1 apheresis has a dramatic suppressive effect on TNFalpha production and is followed by both clinical and immunovirological improvement. G-1 apheresis should be considered in patients in whom HAART is only partially effective.  相似文献   
96.
Fumonisin B1 (FB1) is a water-soluble fungal metabolite that elicits a wide spectrum of toxicological effects. Cellular targets of FB1 include immune cells and in particular macrophages. In the present study the cytotoxic effect of FB1 (1-100 microM) was evaluated using a murine macrophage cell line (J774A.1) as model system. The effect of FB1 on nitric oxide (NO) and prostaglandin E2 (PGE2) production induced by lipopolysaccharide (LPS, 10 and 100 ng/ml) was also investigated. Macrophages were pretreated with FB1 for 72 h and then stimulated with LPS for 24 h. The increase of LPS-induced production of these inflammatory mediators was observed at increasing concentrations of FB1 (0.1-10 microM) and was found to be concentration dependent. By western blot analysis we demonstrated that the observed increase of NO and PGE2 production by FB1 was related to an enhancement of iNOS and COX-2 expression.  相似文献   
97.
Somatic embryogenesis was induced and plant regeneration was obtained in 11 different genotypes of sweet orange navel group [Citrus sinensis (L.) Osb.] from cultures of stigma/style explants and undeveloped ovules. Explants were cultured on 3 different modifications of Murashige and Skoog medium: 500 mg l-1 malt extract; 500 mg l-1 malt extract and 4.6 μM kinetin; and 500 mg l-1 malt extract and 13.3 μM 6-benzylaminopurine. Sucrose (146 mM) was used as carbon source. Somatic embryogenesis occurred 1–3 months after culture initiation from undeveloped ovule and stigma/style cultures of all the genotypes tested. Somatic embryos developed into plantlets with a high frequency (74%) after transfer to Murashige and Skoog medium supplemented with 146 mM sucrose and 500 mg l-1 malt extract. Plants were successfully transferred to soil. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   
98.
“Multi-Omics” technologies have contributed greatly to the understanding of various diseases by enabling researchers to accurately and rapidly investigate the molecular circuitry that connects cellular systems. The tissue-engineered, three-dimensional (3D), in vitro disease model “organoid” integrates the “omics” results in a model system, elucidating the complex links between genotype and phenotype. These 3D structures have been used to model cancer, infectious disease, toxicity, and neurological disorders. Here, we describe the advantage of using the tissue microarray (TMA) technology to analyze human-induced pluripotent stem cell–derived cerebral organoids. Compared with the conventional processing of individual samples, sectioning and staining of TMA slides are faster and can be automated, decreasing labor and reagent costs. The TMA technology faithfully captures cell morphology variations and detects specific biomarkers. The use of this technology can scale up organoid research results in at least two ways: (1) in the number of specimens that can be analyzed simultaneously and (2) in the number of consecutive sections that can be produced for analysis with different probes and antibodies.  相似文献   
99.
High-fidelity simulation (HFS) is a learning method which has proven effective in medical education for technical and non-technical skills. However, its effectiveness for knowledge acquisition is less validated. We performed a randomized study with the primary aim of investigating whether HFS, in association with frontal lessons, would improve knowledge about advanced life support (ALS), in comparison to frontal lessons only among medical students. The secondary aims were to evaluate the effect of HFS on knowledge acquisition of different sections of ALS and personal knowledge perception. Participants answered a pre-test questionnaire consisting of a subjective (evaluating personal perception of knowledge) and an objective section (measuring level of knowledge) containing 100 questions about algorithms, technical skills, team working/early warning scores/communication strategies according to ALS guidelines. All students participated in 3 frontal lessons before being randomized in group S, undergoing a HFS session, and group C, receiving no further interventions. After 10 days from the end of each intervention, both groups answered a questionnaire (post-test) with the same subjective section but a different objective one. The overall number of correct answers of the post-test was significantly higher in group S (mean 74.1, SD 11.2) than in group C (mean 65.5, SD 14.3), p = 0.0017, 95% C.I. 3.34 – 13.9. A significantly higher number of correct answers was reported in group S than in group C for questions investigating knowledge of algorithms (p = 0.0001; 95% C.I 2.22–5.99) and team working/early warning scores/communication strategies (p = 0.0060; 95% C.I 1.13–6.53). Students in group S showed a significantly higher score in the post-test subjective section (p = 0.0074). A lower proportion of students in group S confirmed their perception of knowledge compared to group C (p = 0.0079). HFS showed a beneficial effect on knowledge of ALS among medical students, especially for notions of algorithms and team working/early warning scores/communication.  相似文献   
100.

Background

Hypertension is the leading cause of death in developed countries and reduction of salt intake is recommended as a key preventive measure.

Objective

To assess the dietary sodium and potassium intakes in a national sample of Italian children and adolescents and to examine their relationships with BMI and blood pressure (BP) in the framework of the MINISAL survey, a program supported by the Italian Ministry of Health.

Population and Methods

The study population included 1424 healthy subjects (766 boys, 658 girls) aged 6-18 years (mean age: 10.1±2.9) who were consecutively recruited in participating National Health Service centers in 10 Italian regions. Electrolyte intake was estimated from 24 hour urine collections tested for completeness by the concomitant measurement of creatinine content. Anthropometric indices and BP were measured with standardized procedures.

Results

The average estimated sodium intake was 129 mmol (7.4 g of salt) per day among boys and 117 mmol (6.7 g of salt) among girls. Ninety-three percent of the boys and 89% of the girls had a consumption higher than the recommended age-specific standard dietary target. The estimated average daily potassium intakes were 39 mmol (1.53 g) and 36 mmol (1.40 g), respectively, over 96% of the boys and 98% of the girls having a potassium intake lower than the recommended adequate intake. The mean sodium/potassium ratio was similar among boys and girls (3.5 and 3.4, respectively) and over 3-fold greater than the desirable level. Sodium intake was directly related to age, body mass and BP in the whole population.

Conclusions

The Italian pediatric population is characterized by excessive sodium and deficient potassium intake. These data suggest that future campaigns should focus on children and adolescents as a major target in the framework of a population strategy of cardiovascular prevention.  相似文献   
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