大蒜中两种新的甾体皂甙成分及其对血液凝聚性的影响

用大孔树脂(AB-8)柱层析、硅胶柱层析、Sephadex LH-20柱层析、及制备性HPLC等方法,从大蒜(Alium sativum L.)水溶性部分分到6个化合物,并鉴定其结构,它们分别是proto-iso-eruboside-B(I),eruboside-B(I),iso-eruboside-B(II),sativoside-C(IV),腺苷(V)和色氨酸(VI)。其中I和II为两个新的甾体皂甙类化合物。并测试了它们对血液系统的作用,发现大蒜总甙有抗血小板聚集和提高纤溶活性,iso-eruboside-B有明显的延长血液凝固时间和提高纤溶活性,proto-iso-eruboside-B有显著的提高纤溶活性,腺苷则有抗血小板聚集活性和提高纤溶活性,sativoside-C由于量少未测活性。其余化合物均无活性。     

Homozygosity mapping at Alstrom syndrome to chromosome 2p

Alstrom syndrome is a rare autosomal recessive disorder characterized by pigmentary retinal degeneration, sensorineural hearing loss, childhood obesity, non-insulin-dependent diabetes mellitus, hyperlipidemia and chronic nephropathy. Features occasionally observed include acanthosis nigricans, hypogonadism, hypothyroidism, alopecia, short stature and cardiomyopathy. We report here the results of a linkage study in a large French Acadian kindred, as a first step in identifying the molecular basis of Alstrom syndrome. Evidence of a founder effect made if feasible to use a homozygosity mapping strategy to identify the chromosomal location of the Alstrom gene. In a genome- wide screen, haplotype sharing for a region on chromosome 2 was observed in all affected individuals. Two point linkage analysis resulted in a maximum lod score of 3.84 (theta = 0.00) for marker D2S292. By testing additional markers, the disease gene was localized to a 14.9 cM region on chromosome 2p.      

Treatment of atherosclerotic ostial renal artery stenosis with the intravascular stent

Traditional approaches to revascularization for atherosclerotic ostial renal artery stenosis (RAS) have been suboptimal because of the invasiveness and relatively high perioperative morbidity and mortality of surgery and the low rates of success and long-term patency with percutaneous renal angioplasty (PTRA). We report our 5-year (1991 to 1996) experience with the intravascular stent (Palmaz stent; Johnson & Johnson, Miami Lakes, FL) for the treatment of ostial RAS in 129 patients (63 men, 66 women) and 148 arteries. The mean age of the patients was 71+/-10 years; 98% were hypertensive and 57% had renal dysfunction. Angiographic characteristics of RAS were unilateral in 78%, bilateral in 15%, and single kidney in 7%. The technical success rates were 98% for stent versus 11% for PTRA in the ostial location. The stent restenosis rate (angiographic) was 14% at 8+/-5 months. Systolic and diastolic blood pressures were as follows: baseline, 158+/-3 and 84+/-2 mm Hg; 6 months, 149+/-3 and 81+/-2 mm Hg; 12 months, 149+/-3 and 79+/-2 mm Hg; and 24 months, 135+/-3 and 79+/-2 mm Hg. Follow-up values were significantly lower than baseline (P < 0.05). The number of medications for hypertension initially decreased from 2.2+/-0.1 at baseline to 1.6+/-0.1 and 1.8+/-0.1 at 1 and 3 months, respectively (P < 0.05). By 6 months, however, the number of medications had increased and was not significantly different from before stent placement. Renal function was stable in the group as a whole: Cockroft-Gault creatinine clearance (C-G CrCl) at baseline was 40+/-2 mL/min; at 6 months, 36+/-3 mL/min; at 12 months, 39+/-3 mL/min; and at 24 months, 39+/-4 mL/min. When stratified by degree of renal function, values were similarly stable. Patients with a baseline serum creatinine level of 2 mg/dL or less had C-G CrCl values as follows: baseline, 53+/-3 mg/dL; 6 months, 43+/-4 mg/dL; 12 months, 46+/-4 mg/dL; and 24 months, 52+/-5 mg/dL. Those with a baseline serum creatinine level greater than 2 mg/dL had C-G CrCl values as follows: baseline, 26+/-2 mg/dL; 6 months, 31+/-4 mg/dL; 12 months, 32+/-6 mg/dL; and 24 months, 23+/-3 mg/dL. Of eight patients who were dialysis dependent, four (50%) recovered renal function with a mean serum creatinine level of 2.3+/-0.5 mg/dL at 15+/-6 months (range, 9 to 24 months). Stent placement for the treatment of atherosclerotic ostial RAS has a high success rate and a low rate of restenosis. Control of hypertension improves in most patients. Renal function stabilizes or improves in the majority of patients, even those with severe renal failure. These favorable outcomes are maintained long term.     

Oxygen tension in human tumors: in vivo mapping using CT-guided probes

The role of oxygen in tumor response to therapy has been studied for several decades. We describe a technique that allows in vivo measurement of oxygen in tumors using computed tomography to guide probes. In the evaluation of 16 tumors, oxygen tensions were found to be substantially lower than surrounding tissue and varied nonrandomly. This technique has allowed construction of detailed tumor oxygen level maps.