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1.
Hexane and methanol extracts of heartwood, bark/sapwood and leaves of twelve taxa of Juniperus from the United States were assayed for antifungal and antibacterial activities. The hexane extract of the heartwood of several junipers appeared comparable in antibacterial activity to streptomycin. Antibacterial activity of the hexane extracts from the bark/sapwood of J. monosperma and J. californica were comparable to streptomycin. No appreciable antibacterial activities were found in the leaf extracts from any species examined. No antifungal activities comparable to amphotericin B were found in either hexane or methanol extracts of the heartwood nor from the bark/sapwood. Antifungal activity against Cryptococcus neoformans comparable to amphotericin B was found in the hexane extract of the leaves of J. occidentalis var. australis. The methanol extracts from the leaves of J. osteosperma and J. californica had antifungal activities comparable to amphotericin B against Trichophyton mentagrophytes. 相似文献
2.
We studied 21 patients with bipolar affective disorder and 25 healthy controls in order to determine if tritiated imipramine binding to platelets distinguished the manic from the depressed phase of bipolar disorder. Depressed patients had a significantly lower mean Bmax value (754 +/- 149 fmole/mg protein) than the manic and control groups (1112 +/- 248 and 1237 +/- 201 fmole/mg protein, respectively), which did not differ from each other. These differences could not be attributed to differences in age, sex, menopausal status, the presence of psychotic features or medication history among the subject groups. These findings confirm that decreased imipramine binding to platelets is a state marker for bipolar depression and not a trait marker of bipolar disorder. 相似文献
3.
Purpose. In a continuation of our search for novel antifungal compounds from higher plants, the standard extract of the bark of Pithecellobium racemosum was found to have good activity against important AIDS-related opportunistic yeasts.
Methods. The extract was subjected to bioguided fractionation using silica gel column chromatography which led to purification of triterpene glycosides. The structures of these compounds were determined by a combination of spectroscopic (IR, NMR, HRMS) and chemical methods.
Results. Compound 1 is a new glycoside, 3-O[-L-arabinopyranosyl (1 -2)][-L arabinopyranosyl (1 -6)]2-acetoamido-2-deoxy--D-gluco-pyranosyl oleanolic acid and Compound 2 was identified as the known compound 3-O-[-L-arabinopyranosyl (l-2)]-L-arabinopyranosyl (1-6)] 2-acetamido-2-deoxy--D-glucopyranosyl echinocystic acid.
Conclusions. Compound 1 is a new glycoside, 3-O-[-L-arabinopyranosyl (1-2)]-L-arabinopyranosyl (l-6)]-2-acetoamido-2-deoxy--D-glucopyranosyl oleanolic acid and exhibits moderate antifungal activity against T. mentogrophytes, C. albicans and S. cerevisiae with MIC values of 6.25, 12.5 and 12.5 g/ml respectively. 相似文献
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Multiple myeloma regression mediated by bruceantin. 总被引:1,自引:0,他引:1
Muriel Cuendet Konstantin Christov Daniel D Lantvit Yunfan Deng Samad Hedayat Lawrence Helson James D McChesney John M Pezzuto 《Clinical cancer research》2004,10(3):1170-1179
PURPOSE: Bruceantin has been shown to induce cell differentiation in a number of leukemia and lymphoma cell lines. It also down-regulated c-MYC, suggesting a correlation of down-regulation with induction of cell differentiation or cell death. In the present study, we focused on multiple myeloma, using the RPMI 8226 cell line as a model. EXPERIMENTAL DESIGN: The effects of bruceantin on c-MYC levels and apoptosis were examined by immunoblotting, 4',6-diamidino-2-phenylindole staining, evaluation of caspase-like activity, and 3,3'-dihexyloxacarbocyanine iodide staining. The potential of bruceantin to inhibit primary tumor growth was assessed with RPMI 8226 xenografts in SCID mice, and apoptosis in the tumors was evaluated by the terminal deoxynucleotidyl transferase-mediated nick end labeling assay. RESULTS: c-MYC was strongly down-regulated in cultured RPMI 8226 cells by treatment with bruceantin for 24 h. With U266 and H929 cells, bruceantin did not regulate c-MYC in this manner. Apoptosis was induced in the three cell lines. In RPMI 8226 cells, apoptosis occurred through proteolytic processing of procaspases and degradation of poly(ADP-ribose) polymerase. The mitochondrial pathway was also involved. Because RPMI 8226 cells were the most sensitive, they were used in a xenograft model. Bruceantin treatment (2.5-5 mg/kg) resulted in a significant regression of tumors without overt toxicity. Apoptosis was significantly elevated in tumors derived from animals treated with bruceantin (37%) as compared with the control tumors (14%). CONCLUSIONS: Bruceantin interferes with the growth of RPMI 8226 cells in cell culture and xenograft models. These results suggest that bruceantin should be reinvestigated for clinical efficacy against multiple myeloma and other hematological malignancies. 相似文献
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7.
Epidemiology of premenstrual symptoms in a nonclinical sample. I. Prevalence, natural history and help-seeking behavior 总被引:2,自引:0,他引:2
A stratified sample of 996 nursing school graduates from 1963 to 1984 was surveyed by mail regarding menstrual cycle characteristics. The 730 respondents reported an 87% overall lifetime prevalence of premenstrual symptoms. When the symptoms were categorized according to severity, only 3.2% of the respondents reported severe symptoms. Symptomatic women used diet change (24.6%), exercise (41.8%) and vitamins (18.9%) as self-help measures. Seventeen percent sought advice from a physician. Drug use was common; 22% were using a drug for symptoms at the time of the survey. Despite the common use of treatment, few women reported a significant work impairment. These findings support the conclusion that premenstrual symptoms are common but do not usually interfere with functioning. 相似文献
8.
Callicarpone, a component 10 times as toxic to fish as rotenone, has been isolated from the leaves of Callicarpa candicans. It is reasonable to assume that callicarpone will act as an insecticidal agent as does rotenone. Therefore, the structure-activity relationship of callicarpone was examined by synthesizing a series of compounds having certain of its structural features. Those compounds were tested for insecticidal and antimicrobial activities. A study of synthetic analogs elucidated the functional group chemistry of callicarpone so that a synthesis might be undertaken. Piperitone oxide showed approximately 1/100th the activity of rotenone against Daphnia magna. 1-(alpha-Hydroxyisopropyl)-3-oxocyclohexene oxide showed activity against myobacterium while 2,3,4,6,7,8-hexahydronaphthalene-1,4-dione showed inhibitory activity against the mycobacterium and two yeasts. 相似文献
9.
10.
Fitzgerald JT Sena MJ Vandewalker KN Johnson JR Griffey SM Tarantal AF Barry PA McChesney MB Ramsamooj R Perez RV 《Transplantation》2004,78(3):367-374
BACKGROUND: Occult systemic inflammation, as manifested by increased levels of C-reactive protein (CRP), identify patients at increased risk for renal allograft rejection. The mechanisms linking occult systemic inflammation to these adverse outcomes remain unclear. The purpose of this study was to examine the anatomic and physiologic effects of occult pretransplantation systemic inflammation on posttransplantation allograft outcome in a nonhuman primate model. METHODS: Seventy-one healthy male Rhesus macaques were stratified into quartiles based on serum CRP. Five high quartile and six low quartile animals underwent common iliac artery transplantation from male donors. Duplex ultrasound measured graft flow at 3 weeks postoperatively; luminal narrowing was assessed by graft/femoral peak systolic velocity ratio. At 6 weeks, the grafts were harvested and morphometry studies were performed. Vessel wall changes were assessed by measuring the intimal medial area. RESULTS: The allografts placed in high CRP quartile animals had more luminal narrowing by 3 weeks than those placed in low quartile animals, as evidenced by a higher mean graft/femoral peak systolic velocity ratio (1.6 vs. 0.90, P=0.006). Morphometry studies after graft harvest showed increased vessel wall area in the high quartile group versus the low quartile group (1.39 mm vs. 1.03 mm, P=0.018). CONCLUSIONS: Occult pretransplantation systemic inflammation is associated with increased intimal thickening and stenosis after arterial allograft transplantation in a primate model. Additional studies are needed to confirm these results and to further investigate potential mechanisms linking pretransplantation systemic inflammation to adverse outcomes after transplantation. 相似文献