神经生长因子对小鼠突触体内Ca^2＋水平的调节作用

观察了多次海马内微注射ＮＧＦ对小鼠突触体内游离钙水平的影响，并在离体情况下观察ＮＧＦ对ＥＧＴＡ和ＣａＣｌ２分别造成突触体内低钙和高钙状态的调节作用。结果如下：（１）在体实验表明，一定剂量的ＮＧＦ可显著降低老年小鼠海马突触体内游离钙水平（Ｐ＜００５）；（２）离体实验表明，当突触体游离钙水平降低时，适当剂量的ＮＧＦ具有升高游离钙水平的作用；而突触体内游离钙水平升高时，则ＮＧＦ有降低游离钙水平的作用。提示ＮＧＦ对游离钙水平的双向调节作用可能是ＮＧＦ改善老年性记忆衰退的作用机制。     

Off-pump resection of a coronary arterial fistula using the Harmonic Scalpel

Off-pump surgery was performed in a patient with post-infarction angina complicated with aneurysmal coronary-pulmonary arterial fistula. Epicardial echocardiography localized the artery feeding the fistula in the myocardium, which had not been revealed by visual inspection, palpation, or transesophageal echocardiography. The patient underwent off-pump coronary artery bypass grafting concomitant with aneurysmectomy. The feeding arteries were dissected easily using a Harmonic Scalpel and ligated. The flow in the aneurysm disappeared immediately and aneurysmectomy was performed without bleeding.     

Herpetic croup: two case reports and a review of the literature

Croup is an acute infectious illness usually occurring in children; it is characterized by brassy cough and stridor. The main pathogens include mainly parainfluenza and influenza viruses. Recently there have been reports of prolonged croup caused by the herpes simplex viruses. We report two cases of prolonged croup due to herpes simplex types 1 and 2. We also review and summarize the reported pediatric cases of herpetic croup.     

Induced luteolysis in the primate: rapid loss of luteinizing hormone receptors

The molecular mechanisms involved in luteolysis are still unclear in the primate. This study aimed to investigate the effect of induced luteolysis on the ovarian luteinizing hormone (LH) receptor and the steroidogenic enzyme, 3beta-hydroxysteroid dehydrogenase (3beta-HSD) in the marmoset monkey. Luteolysis was induced in the mid-luteal phase either directly by systemic prostaglandin F2alpha (PGF2alpha), or indirectly by LH withdrawal using systemic gonadotrophin releasing hormone antagonist (GnRHant) treatment. The LH receptor was studied by isotopic mRNA in-situ hybridization and in-situ ligand binding and 3beta-HSD expression was studied using isotopic mRNA in-situ hybridization and immunohistochemistry. Induced luteolysis was associated with a reduction in the expression of LH receptor (P < 0.0001) and 3beta-HSD mRNA, closely followed by a reduction in the LH receptor (P < 0.05) and 3beta-HSD protein concentrations within 24 h. There were no differences in the findings whether luteolysis was induced with PGF2alpha or GnRHant. This study shows that disparate mechanisms to induce luteolysis in the primate result in an identical rapid loss of the LH receptor and 3beta-HSD. In conclusion, induced luteolysis leads to rapid loss of the steroidogenic pathway in luteal cells.      

Spermicidal activity of chelated complexes of bis(cyclopentadienyl)vanadium(IV)

Transition metal complexes containing vanadium IV have been shown to modulate the cellular redox potential and catalyse the generation of reactive oxygen intermediates (ROI). Since sperm function is exquisitely susceptible to ROI, we examined the effects of stable chelate complexes of vanadocenes on human sperm motility. We synthesized seven structurally distinct chelate complexes of bis(cyclopentadienyl)vanadium(IV) with bidentate ligands [i.e. vanadocene acetylacetonato monotriflate (VDacac), vanadocene hexafluoro acetylacetonato monotriflate (VDHfacac), vanadocene N-phenyl benzohydroxamato monotriflate (VDPH), vanadocene acethydroxamato monotriflate (VDH), vanadocene catecholate (VDCAT), vanadocene bipyridino ditriflate (VDBPY), and vanadocene dithiocarbamate monotriflate (VDDTC)], and evaluated their spermicidal activity using computer-assisted sperm analysis (CASA; Hamilton-Thorne). All seven chelate complexes of vanadocene elicited potent spermicidal activity at micromolar concentrations (EC50 values: 3.9-106 microM) without affecting the sperm acrosome integrity. The catecholate and acetylacetonate complexes of vanadocene were the most active and the bipyridyl complex the least active with an order of efficacy VDCAT > VDacac > VDDTC > VDPH > VDH > VDHfacac > VDBPY. The spermicidal activity of chelate complexes of vanadocenes was rapid and irreversible since the treated spermatozoa underwent apoptosis, as determined by the flow cytometric analysis of mitochondrial membrane potential, surface annexin V binding assay, in-situ nick-end labelling of sperm nuclei, and confocal laser scanning microscopy. These results provide unprecedented evidence that chelate complexes of vanadocene with bidentate ligands have spermicidal and apoptosis inducing properties. These vanadocene complexes, especially VDacac, may be useful as contraceptive agents.      

Community Hospital-based Stroke Programs: North Carolina, Oregon, and New York. I: Goals, objectives, and data collection procedures

In order to assess the impact of variations in stroke care on outcomes, and to make geographic comparisons, the three Community Hospital-Based Stroke Programs in North Carolina, Oregon, and New York, aggregated their data on 4,132 hospitalized stroke patients. Complete demographic data or "Major Profile" were obtained on 2,390 (57.8%) of the 4,132 stroke patients. This includes those patients on whom informed patient and physician consents were obtained during the hospitalization. Of the major profile patients, 1,490 (62.3%) were followed for periods up to one year, 502 (21.0%) were lost to followup and 398 (16.6%) died within the one year followup period. Incomplete demographic data or "Minor Profile" were observed on 1,742 (42.1%) of the 4,132 patients. Minor profile includes those who died before comprehensive interviews were completed or those for whom informed consent for an interview could not be obtained. Of the minor profile group, 813 (46.7%) died in hospital, and 929 (53.3%) were alive when discharged from the hospital. This paper, which describes the programs, data collection procedures, and study cases, also highlights specific issues on stroke diagnosis, risk factors associated with stroke, and the influence of interventions on stroke outcomes. We conclude that: 1) the merging of data on hospitalized stroke cases from rural and urban hospitals in geographically distinct regions can be used in the study of stroke diagnosis, the use of diagnostic tests, and the effect of interventions on stroke outcomes; and 2) these data are consistent with the hypothesis that part of the national decline in mortality from stroke is due to a decline in stroke severity.     

HMG-CoA reductase inhibitors (statins): a promising approach to stroke prevention

Statins represent a promising class of agents to prevent stroke. In randomized trials of middle-aged patients with coronary artery disease, statins reduce the incidence of stroke. The reduction in stroke may not be solely related to cholesterol or low-density lipoprotein reduction but may involve nonsterol mechanisms effects on endothelial cells, macrophages, platelets, and smooth muscle cells. Statins also reduce the size of cerebral infarction in a murine stroke model, suggesting a neuroprotective effect. The best current evidence for stroke prevention is with pravastatin and simvastatin. Pravastatin reduces the risk of stroke in patients with coronary artery disease and average cholesterol levels; simvastatin reduces the risk of the combined endpoint of stroke and transient ischemic attack in hypercholesterolemic patients with coronary artery disease. Future studies of statins are needed in stroke populations, particularly the elderly.