金翼黄芪甙A的化学结构和绵毛黄芪甙ⅩⅤ及7,2′-二羟基-3′,4′二甲氧基异黄烷-7-O-β-D-葡萄糖甙二维核磁共振谱的研究

从金翼黄芪中分离出金翼黄芪甙A(Ⅰ),绵毛黄芪甙XV (Ⅱ),7,2′-二羟基-3′,4′-二甲氧基异黄烷-7-O-β-D-葡萄糖甙(Ⅲ),大豆皂甙Ⅰ,胡萝卜甙及β-谷甾醇。Ⅰ为新化合物,确定其结构为3-O-[α[-L-鼠李吡喃糖基(1→2)-D-木吡喃糖基]-环黄芪醇。并应用二维核磁共振相关谱对Ⅱ和Ⅲ的~1H和~(13)C化学位移信号进行了全面归属。     

Oral lesions of HIV infection in developing countries

HIV infection has spread rapidly within developing countries since it was first recognized in the early 1980s. The purpose of this paper is to review the prevalence of oral lesions associated with HIV infection (oral HIV) in the developing world, and to identify additional factors that may complicate the presentation of these lesions. Direct comparison of regional and local prevalence studies within Africa, India and Thailand is speculative because there are few reports available. Furthermore, inherent differences in study design, data collection, standardization and calibration of health workers make any inferences inconclusive. Additional prevalence studies of oral HIV lesions associated with systemic disease or social conditions, such as poverty or malnutrition, are needed. In order to provide a basis for the diagnosis and treatment of HIV-associated oral lesions in the developing world, it is important to recognize any confounding factors that may impact on their presentation and management. Elucidation of these various factors may provide a basis for treatment within the developing and developed world.     

Experimental headache in humans

The need for valid human experimental models of headache is obvious. Several compounds have been proposed as headache-inducing agents, but only the nitroglycerin (NTG) model has been validated. In healthy subjects, intravenous infusions of the nitric oxide (NO) donor NTG induce a dose-dependent headache and dilatation of the temporal, radial and middle cerebral artery. NTG-induced headache, although less intense, resembles migraine in pain characteristics, but the accompanying symptoms are rarely present. Cephalic large arteries are dilated during migraine headache as well as during NTG headache. N-acetylcysteine enhances the formation of NO and potentiates NTG-induced headache, whereas mepyramine, a H1 -antagonist capable of blocking histamine-induced headache, has no effect. Thus, the headache is dependent on NO or other steps in the NO cascade. The model is useful for pharmacological interventions and sumatriptan reduced the NTG-induced headache. The NTG model may be a valuable tool in the development of future migraine drugs.     

Neutrophil dermatosis of the dorsal hands

Neutrophil dermatosis of the dorsal hands (NDDH) is a recently described skin manifestation regarded as a subset of acute febrile neutrophilic dermatotis (Sweet syndrome). We describe 5 cases with pustular and ulcerative plaques and/or bullae and vesicles of the dorsal hands. Three of the patients also had skin changes at sides other than the hands. Associated conditions were found in two patients, one patient treated with hemo-dialysis for chronic glomerulonephritis, and one patient had suffered from a streptococcal tonsillitis prior to the eruption. Two of the patients had fever, two had neutrophil leucocytosis in peripheral blood and two had elevated sedimentation rates. Histological findings showed signs of vasculitis in biopsies from two of the patients. NDDH is discussed on the basis of prior case reports concerning the subject, and it is concluded that Neutrophil dermatosis of the dorsal hands should be regarded as a localized variety of Sweet syndrome.     

Headache induced by a nitric oxide donor (nitroglycerin) responds to sumatriptan. A human model for development of migraine drugs

Experimental "vascular" headache in humans may be used in characterizing new migraine drugs. The effects of sumatriptan on nitroglycerin-(NTG)-induced headache and arterial responses were therefore studied. Following a double-blind randomized crossover design, 10 healthy volunteers received sumatriptan 6 mg s.c. or placebo succeeded by 20 min NTG (0.12 mg/kg/min) infusion. Headache was rated on a 10 points scale. Temporal and radial artery diameters and velocity in the middle cerebral artery (MCA) were measured with ultrasound. Sumatriptan reduced the NTG-induced headache, median score 1.5 versus 4 after placebo ( p <0.01) and decreased temporal and radial artery diameters 75±3 and 86±3% of baseline respectively ( p <0.05), Blood velocity in the MCA was unaffected. The NTG model may prove to be a valuable tool in the development of future migraine drugs. The results suggest that NTG headache in non-migraineurs may share mechanisms with migraine headache.     

16层螺旋CT血管造影对冠状动脉狭窄的评价

目的:分析16层螺旋CT血管造影(MSCTA)无创性评价冠状动脉(冠脉)狭窄的价值.方法:80例临床初诊疑为冠心病,既往无冠脉成形术和搭桥术史的患者,行冠脉16层MSCTA后(其中9例在CT扫描前心率超过80次/min的患者应用了β受体阻滞剂),回顾性重建心电门控轴位图像,并分别采用容积成像、多平面重建、曲面重建、最大密度投影等后处理方法,对所有冠脉及其分支进行重建,统计可供临床评价的、管径≥1.5 mm的冠脉段,以选择性冠脉造影(SCA)为标准,对比分析MSCTA诊断冠脉显著性狭窄(管腔平均直径缩小>50%)的准确性.结果:94%(989/1056)的冠脉节段和94%(290/310)的冠脉主支可供评价,(6%)67/1056段不能评价的主要原因分别为:心脏运动伪影39段,致密钙化20段和管腔显影不良8段.除外不能评价的冠脉,按节段和主支分类,与SCA相比,MSCTA诊断冠脉显著性狭窄的差异无统计学意义,其敏感性、特异性、阳性和阴性预期值分别为93%、99%、87%、99%和95%、98%、91%及99%.结论:在患者心率<80次/min时,16层MSCTA即可获得较好的图像质量用于评价冠脉并判断其狭窄程度,是一种值得临床医生信赖的检查冠脉有无狭窄的无创伤性方法.     

The RAR-RXR as well as the RXR-RXR pathway is involved in signaling growth inhibition of human CD34+ erythroid progenitor cells

Previous studies have shown that retinoic acid (RA), similar to tumor necrosis factor-alpha (TNF-alpha), can act as a bifunctional regulator of the growth of bone marrow progenitors, in that it can stimulate granulocyte-macrophage colony-stimulating factor (GM-CSF)- or interleukin-3 (IL-3)-induced GM colony formation, but potently inhibit G-CSF-induced growth. The present study, using highly enriched human CD34+ as well as Lin- murine bone marrow progenitor cells, demonstrates a potent inhibitory effect of 9-cis-RA on burst-forming unit-erythroid (BFU-E) colony formation regardless of the cytokine stimulating growth. Specifically, 9-cis-RA potently inhibited the growth of BFU-E response to erythropoietin (Epo) (100%), stem cell factor (SCF) + Epo (92%), IL- 3 + Epo (97%), IL-4 + Epo (88%), and IL-9 + Epo (100%). Erythroid colony growth was also inhibited when CD34+ progenitors were seeded at one cell per well, suggesting a direct action of RA. Using synthetic ligands to retinoic acid receptors (RARs) and retinoid X receptors (RXRs) that selectively bind and activate RAR-RXR or RXR-RXR dimers, respectively, we dissected the involvement of the two retinoid response pathways in the regulation of normal myeloid and erythroid progenitor cell growth. Transactivation studies showed that both the RAR (Ro 13- 7410) and RXR (Ro 25-6603 and Ro 25-7386) ligands were highly selective at 100 nmol/L. At this concentration, Ro 13-7410 potently inhibited G- CSF-stimulated myeloid as well as SCF + Epo-induced erythroid colony growth. At the same concentration, Ro 25-6603 and Ro 25-7386 had little or no effect on G-CSF-induced colony formation, whereas they inhibited 75% and 53%, respectively, of SCF + Epo-stimulated BFU-E colony growth. Thus, the RAR-RXR response pathway can signal growth inhibition of normal bone marrow myeloid and erythroid progenitor cells. In addition, we demonstrate a unique involvement of the RXR-RXR pathway in mediating growth inhibition of erythroid but not myeloid progenitor cells.