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In this study, three steroidal sapogenins (Delta3 diosgenin, diosgenin, and pennogenin) and the phytosterols, stigmasterol and beta-sitosterol were isolated from Jamaican bitter yam, Dioscorea polygonoides. Their effects on fasting blood glucose and intestinal amylase and ATPases in streptozotocin-induced diabetic rats were studied. The diabetic rats (fed supplemented and unsupplemented diets) lost weight significantly compared to the normal group. There was a significant increase in the activity of alpha-amylase in the proximal region of the small intestinal mucosa of diabetic rats fed sapogenin extract or commercial diosgenin. However, this did not result in increased fasting blood glucose. Instead, supplementation of the diet with bitter yam sapogenin extract significantly decreased fasting blood glucose compared to the diabetic group. Supplementation of the diet with bitter yam sapogenin extract or commercial diosgenin significantly reduced Na+-K+-ATPase activity in all three regions compared to the diabetic control group. Commercial diosgenin supplementation resulted in a significant increase in Ca2+ ATPase activity in proximal region compared to the diabetic control and bitter yam sapogenin extract groups. The effect of bitter yam sapogenin extract or commercial diosgenin on intestinal Na+-K+-ATPase activity could account for their hypoglycemic properties. However, there was adverse effect on the body weight.  相似文献   
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Imatinib mesylate (GLEEVEC, GLIVEC, formerly STI571) has demonstrated unprecedented efficacy as first-line therapy for treatment for all phases of chronic myelogenous leukemia and metastatic and unresectable malignant gastrointestinal stromal tumors. Disposition and biotransformation of imatinib were studied in four male healthy volunteers after a single oral dose of 239 mg of (14)C-labeled imatinib mesylate. Biological fluids were analyzed for total radioactivity, imatinib, and its main metabolite CGP74588. Metabolite patterns were determined by radio-high-performance liquid chromatography with off-line microplate solid scintillation counting and characterized by liquid chromatography-mass spectrometry. Imatinib treatment was well tolerated without serious adverse events. Absorption was rapid (t(max) 1-2 h) and complete with imatinib as the major radioactive compound in plasma. Maximum plasma concentrations were 0.921 +/- 0.095 mug/ml (mean +/- S.D., n = 4) for imatinib and 0.115 +/- 0.026 mug/ml for the pharmacologically active N-desmethyl metabolite (CGP74588). Mean plasma terminal elimination half-lives were 13.5 +/- 0.9 h for imatinib, 20.6 +/- 1.7 h for CGP74588, and 57.3 +/- 12.5 h for (14)C radioactivity. Imatinib was predominantly cleared through oxidative metabolism. Approximately 65 and 9% of total systemic exposure [AUC(0-24 h) (area under the concentration time curve) of radioactivity] corresponded to imatinib and CGP74588, respectively. The remaining proportion corresponded mainly to oxidized derivatives of imatinib and CGP74588. Imatinib and its metabolites were excreted predominantly via the biliary-fecal route. Excretion of radioactivity was slow with a mean radiocarbon recovery of 80% within 7 days (67% in feces, 13% in urine). Approximately 28 and 13% of the dose in the excreta corresponded to imatinib and CGP74588, respectively.  相似文献   
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BACKGROUND: The MLL 11q23 translocation arises in utero and is present in 75% of infant leukemias. That MLL+ acute myeloid leukemia (AML) can arise following chemotherapy with DNA topoisomerase II (DNAt2) inhibitors suggests that these substances, which also occur naturally in foods, may contribute toward infant leukemia. We hypothesized that maternal consumption of dietary DNAt2 inhibitors during pregnancy would increase the risk of infant leukemia, particularly AML(MLL+). METHODS: This Children's Oncology Group case-control study consisted of 240 incident cases of infant acute leukemia [AML and acute lymphoblastic leukemia (ALL)] diagnosed during 1996 to 2002 and 255 random digit dialed controls. Maternal diet during pregnancy was determined through a food frequency questionnaire. An index of specific foods identified a priori to contain DNAt2 inhibitors as well as vegetables and fruits were created and analyzed using unconditional logistic regression. RESULTS: There was little evidence of an association between the specific DNAt2 index and leukemia overall and by subtype. An exception was AML(MLL+); odds ratios (95% confidence intervals) comparing the second to fourth quartiles to the first were 1.9 (0.5-7.0), 2.1 (0.6-7.7), and 3.2 (0.9-11.9), respectively (P for trend = 0.10). For the vegetable and fruit index, there were significant or near-significant inverse linear trends for all leukemias combined, ALL(MLL+), and AML(MLL-). CONCLUSION: Overall, maternal consumption of fresh vegetables and fruits during pregnancy was associated with a decreased risk of infant leukemia, particularly MLL+. However, for AML(MLL+) cases, maternal consumption of specific DNAt2 inhibitors seemed to increase risk. Although based on small numbers, these data provide some support for distinct etiologic pathways in infant leukemia.  相似文献   
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PURPOSE: Optical coherence tomography (OCT) imaging was evaluated to determine if radiation-induced mucosal damage could be noninvasively monitored in real time and correlated with histopathologic findings. EXPERIMENTAL DESIGN: Female C3H mice, ages 7 to 9 weeks, four per group, were immobilized in a custom-made Lucite jig and received 0, 15, 22.5, and 25 Gy in a single fraction to their oral cavity. OCT images were acquired of proximal, middle, and distal aspects of the dorsum of the tongue on days 0, 1, 3, 5, and 7 post-irradiation. Animals were sacrificed on day 7 and samples taken for histologic evaluation. OCT images were visually examined and also quantified by image analysis and compared with histologic findings. RESULTS: Tongues removed 7 days post-irradiation showed no visible damage; however, upon staining with toluidine blue, ulcers at the base of the tongue became visible (100% for 25 Gy, 75% after 22.5 Gy, and 0% after 15 Gy). Visual inspection of OCT images qualitatively compared with histologic findings and quantitative image analysis of the OCT images (effective light penetration depth) revealed significant changes 7 days post-irradiation compared with unirradiated controls for the base of the tongue. CONCLUSIONS: OCT allows for direct noninvasive real-time acquisition of digitally archivable images of oral mucosa and can detect radiation-induced changes in the mucosa before visual manifestation. OCT may be a useful technique to quantify subclinical radiation-induced mucosal injury in experimental chemoradiation clinical trials.  相似文献   
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Cavernous hemangioma (CH) of urinary bladder occurs relatively infrequently, accounting for 0.6% of all bladder tumors. This tumor may occur sporadically or coexist with other benign and malignant vascular lesions. In this report, we present a rare case of CH in a 3‐year‐old Ugandan girl. A 3‐year‐old girl was referred to Mbarara Regional Referral Hospital (MRRH) for urological evaluation following a 3‐year history of intravaginal swelling, dysuria, and heavy hematuria resulting in anemia. Imaging was consistent with polypoid bladder mass arising from the bladder trigone. Embryonal rhabdomyosarcoma was suspected based on clinical eyeballing. She was worked up for chemotherapy and received 26 cycles of vincristine sulfate, actinomycin‐d, and cyclophosphamide (VAC). Biopsy and fulguration were performed after optimizing the patient. Histopathology confirmed CH. The surgery was uneventful and resulted in complete cure. CH should be considered in the differential diagnosis of childhood genitourinary masses. It is a rare entity in the real‐life clinical practice and therefore can be overlooked. Excision biopsy and histology should be performed before initiating the patients to chemotherapy. CH is very insensitive to chemotherapy and therefore surgery maybe adequate in resource‐limited settings.  相似文献   
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Aim:  The present study was carried out to analyze the maternal death rate and its changing trends over a 20-year period in a large referral/teaching institution in Eastern India.
Methods:  A retrospective analysis of maternal deaths was carried out from January 1986 to December 2005 at the Department of Obstetrics and Gynaecology, R. G. Kar Medical College and Hospital, Kolkata, India. Records were divided into four 5-yearly periods: 1986–1990; 1991–1995; 1996–2000; and 2001–2005, for comparison of the trends. The initial interval from 1986 to 1990 was chosen as the reference period.
Results:  The cumulative maternal mortality ratio (MMR) was 599.3 per 100 000 live births. Comparison between the first 5-year period (1986–1991) and the last (2001–2005) showed a statistical significant downward trend in MMR (683.6 vs 474.3; P  < 0.001). Deaths due to direct causes are still the leading cause, accounting for 82.09% of total deaths. Hypertensive disorders (36.14%), hemorrhage (21.91%) and sepsis (19.54%) were still the major causes of direct obstetric deaths throughout the study period. Hypertensive disorders alone showed a substantial decline after the introduction of magnesium sulphate.
Conclusion:  The fall in maternal mortality has been very slow.  相似文献   
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