Development and regulation of substance P expression in neurons of the tadpole optic tectum.

Activity-dependent synaptic plasticity is characteristic of developing visual systems. Using the frog retinotectal system, we investigated the extent to which afferent input affects neurotransmitter expression in a target structure. We have concentrated on a particular subpopulation of tectal cells that is immunoreactive to substance P (SP). Early in development, SP expression in tectal neurons was restricted to the anterior lateral region of the tectum. As tadpoles developed, this expression expanded into progressively more posterior and medial regions in a manner that closely followed the gradient of tectal maturation. At all times, however, anterior and lateral tectal regions had a greater percent of SP-like immunoreactive (SP-ir) cells than posterior and medial ones. Horseradish peroxidase (HRP) labeling of the retinal ganglion cell projection in conjunction with SP immunocytochemistry demonstrated that innervation by retinal ganglion cell terminals preceded the expression of SP by tectal cells. This suggested that the optic nerve may influence SP differentiation and/or expression. In support of this idea, transection of the optic nerve resulted in a decrease in SP expression in the deafferented tectal lobe of tadpoles. This result, opposite to that seen previously in the adult, also indicates that optic nerve-dependent regulation of SP expression in the developing and mature systems occurs through different pathways.     

增生性玻璃体视网膜病变玻璃体切割物的细胞凋亡观察

目的观察增生性玻璃体视网膜病变玻璃体切割物的细胞凋亡情况 。方法收集60例不同分级的增生性玻璃体视网膜病变患者的玻璃体切割物,核苷酸末端转移酶介导dUTP缺口翻译法(TdT-mediated dUTP nick end label ling method,TUNEL法)标记凋亡细胞,光镜观察。结果60例患者的玻璃体切割物均有细胞凋亡的特征性改变,随着病变程度的加重,非色素细胞凋亡总数逐渐减少,并出现色素细胞凋亡。结论增生性玻璃体视网膜病变存在不同类型细胞的凋亡,细胞凋亡是调控其病变程度的重要机制之一。(中华眼底病杂志,1999,15:81-83)     

Liver Targeting of Interferon Through Pullulan Conjugation

Purpose. The purpose of this study was to actively target interferon (IFN) to the liver through its chemical conjugation with pullulan, a water-soluble polysaccharide with a high affinity for the liver. Methods. Chemical conjugation of IFN with pullulan was achieved by a cyanuric chloride method. Following intravenous injection of the conjugates to mice, their body distribution and the activity of an IFN-induced enzyme, 2,5-oligoadenylate (2-5A) synthetase in the liver and other organs, were evaluated. Results. The cyanuric chloride method enabled us to prepare an IFN-pullulan conjugate that retained approximately 7–9 % of the biological activity of IFN. Pullulan conjugation enhanced the liver accumulation of IFN and the retention period with the results being reproducible. When injected intravenously to mice, the IFN-pullulan conjugate enhanced the activity of 2-5A synthetase in the liver. The activity could be induced at IFN doses much lower than those of free IFN injection. In addition, the liver 2-5A synthetase induced by conjugate injection was retained for 3 days, whereas it was lost within the first day for the free IFN-injected mice. Conclusions. IFN-pullulan conjugation was promising for IFN targeting to the liver with efficient exertion of its antiviral activity therein.     

Effects of pesticide seed treatments onRhizobium japonicum and its symbiotic relationship with soybean

Summary SeventeenRhizobium japonicum cultures isolated from soybean nodules induced formation of nodules on taproots of soybean plants. All isolates reduced acetylene to ethylene to different extentsin vitro. Paper disc assay indicated that two insecticides, lindane (-1,2,3,4,5,6-hexachlorocyclohexane), chlorpyrifos (O,O-diethyl O-3,5,6-trichloro-2-pyridyl phosphorothioate), and a fungicide, thiram (tetramethylthiuratn disulphide) individually or in combination caused significant inhibition of the growth ofR. japonicum No. 16.The effects of insecticide-fungicide seed treatments on the nitrogenase activity of soybean plants in nitrogen-fixing capacity, weights of leaves, stems, and nodules were determined. Thiram, singly or in combination with lindane and/or chlorpyrifos, significantly delayed growth of the plants and affected the activity of nitrogenase in the fixation of nitrogen 3 weeks after treatments. No drastic effect of any of the pesticide treatments on soybean plant growth was observed after 8 weeks.Contribution No., Research Institute, Agriculture Canada, London, Ontario.     

Sex differences and similarities in the management and outcome of stroke patients

BACKGROUND AND PURPOSE: Previous studies have documented sex differences in the management and outcome of patients with cardiovascular disease. However, little data exist on whether similar sex differences exist in stroke patients. We conducted a study to determine whether sex differences exist in patients with acute stroke admitted to Ontario hospitals. METHODS: Using linked administrative databases, we performed a population-based cohort study. The databases contained information on all 44 832 patients discharged from acute-care hospitals in Ontario between April 1993 and March 1996 with a most responsible diagnosis of acute stroke. The main outcomes measured consisted of sex differences in comorbidities, the use of rehabilitative services, the use of antiplatelet therapy and anticoagulants (in elderly stroke survivors aged > or =65 years only), discharge destination, and mortality. RESULTS: Male stroke patients were more likely than female stroke patients to have a history of ischemic heart disease (18.1% versus 15.3%, respectively; P<0.001) and diabetes mellitus (20.1% versus 18. 7%, respectively; P<0.001), whereas female patients were more likely than male patients to have hypertension (33.8% versus 30.0%, respectively; P<0.001) and atrial fibrillation (12.9% versus 10.2%, respectively; P<0.001). There were no sex differences in the usage of in-hospital rehabilitative services. The overall 90-day postdischarge use of aspirin and ticlopidine was similar in stroke survivors aged 65 to 84 years. However, among stroke survivors aged > or =85 years, men were more likely than women to receive aspirin (36. 0% versus 30.7%, respectively; P<0.001) and ticlopidine (9.2% versus 6.8%, respectively; P=0.007). Use of warfarin was similar for the two sexes. Men were more likely than women to be discharged home (50. 6% versus 40.9%, respectively; P<0.001) and less likely to be discharged to chronic care facilities (16.8% versus 25.2%, respectively; P<0.001). The risk of death 1 year after stroke was somewhat lower in women than men (adjusted odds ratio 0.939, 95% CI 0.899 to 0.980; P=0.004). The mortality differences were greatest among elderly stroke patients. CONCLUSIONS: Elderly men are more likely than elderly women to receive aspirin and ticlopidine and equally like to receive warfarin after a stroke. Despite these differences, elderly women have a better 1-year survival after a stroke.     

Rate of stroke recurrence in patients with primary intracerebral hemorrhage

BACKGROUND AND PURPOSE: Primary intracerebral hemorrhage (PICH) is a devastating illness with high early mortality. Hypertension is a major risk factor both for ischemic cerebrovascular disease and for intracranial hemorrhage. Survivors of PICH are at risk for both recurrent hemorrhage and ischemic cerebrovascular disease. We sought to determine the rate of recurrence of ICH or cerebral ischemia in a cohort of PICH patients at the Toronto Hospital, Toronto, Canada. METHODS: A retrospective search of computerized hospital records from 1986 to 1996 for patients with a discharge diagnosis of intracerebral hemorrhage (International Classification of Diseases, Ninth Revision-Clinical Modification [ICD-9-CM] code 431) was conducted to identify the index cases. Charts were abstracted for demographic and clinical characteristics. CT scans, MR scans, or radiologist reports were reviewed. To determine recurrence, the database was linked to the Ontario Provincial Government Vital Statistics Registry and to the Canadian Institute for Health Information database of hospital discharge abstracts. Logistic regression analysis was used to identify predictive factors for mortality after PICH. A Cox proportional hazards model was fitted to identify predictive factors for recurrent ICH or stroke. RESULTS: A total of 746 charts were identified by computer search. After abstraction, 423 index patients with PICH were identified. Of these, 27.4% died in the first 30 days of their admission. Predictors of death were age, intraventricular rupture of hemorrhage, and trilobar hemorrhage. The recurrence rate for PICH was 2.4% (95% CI 1.4% to 3. 9%) per year, whereas the recurrence rate for ischemic cerebrovascular disease was 3.0% (95% CI 1.8% to 4.7%) per year. The only significant predictor of readmission for ICH was lobar location of the index hemorrhage, with a hazard ratio of 3.8 (95% CI 1.2 to 12.0). CONCLUSIONS: PICH has a high 30-day mortality rate. Survival from the initial insult portends a moderate risk of recurrence of 2. 4% per year for PICH and 3.0% per year for ischemic cerebrovascular disease. Patients with PICH are at risk for both ischemic stroke or TIA and recurrent hemorrhage; thus, PICH may be a marker for ischemic stroke. Patients with lobar hemorrhage have a 3.8-fold increased risk of recurrent ICH.     

Transarterial embolisation of complex cavernous sinus dural arteriovenous fistulae with low-concentration cyanoacrylate

We report the effectiveness of low-concentration n-butyl-2-cyanoacrylate (NBCA)-Lipiodol-tungsten mixture (10–15 %) in the management of patients with aggressive or recurrent complex cavernous dural arteriovenous fistulae (CSDAVF). We treated five patients with complex CSDAVF with a low concentration of an NBCA-Lipiodol-tungsten mixture after catheterisation of the feeding arteries arising from the external carotid artery. Three had a recurrent CSDAVF after transarterial particulate embolisation. Three refused transvenous treatment or could not be treated in this way; two patients had also feeding dural branches of the internal carotid artery. All patients had complete resolution of symptoms and signs within a month of the procedure. No definite neurological complication was found during follow-up ranging from 12 to 36 months. Transarterial embolisation with low-concentration cyanoacrylate appears to be an effective alternative management of aggressive or recurrent CSDAVF. Received: 8 November 1999/Accepted: 2 March 2000     

小儿耳蜗植入后电诱发复合动作电位的阈值及其临床应用

目的：研究应用神经反应遥测（neural response telemetry,NRT)技术，测试电诱发复合动作电位（electrically-evoked compound action potential,ECAP)阈值以指导小儿人工耳蜗映射调图的策略与时机。方法：应用NRT3．0软件对辐值增长函数进行线性拟合，确定ECAP阈值。比较6例儿童植入者在术后1、2、3个月ECAP阈值的变化，同时比较了7例儿童术中、术后ECAP阈值的差异。结果：ECAP幅值增长函数在接近阈值或进入饱和时不再呈线性。术后ECAP阈值保持稳定。各导电极的术中ECAP阈值比术后阈值平均高约15CL，二者有显著性相关（R2＝0．9154）。结论：应选取幅值增长函数的直线段部分进行拟合以确定ECAP阈值。术后应用ECAP阈值指导小儿映射调图时，测试一次ECAP阈值即可。术中ECAP阈值可用作开机时映射图的C值。     

腹腔镜与腹腔镜辅助乙状结肠代阴道术治疗MRKH综合征

目的 :总结使用全腹腔镜和腹腔镜辅助下乙状结肠阴道成形术各成功治疗1例Mayer Rokitansky Kuster Hauser综合征 (MRKH综合征 )的经验。方法 :全腹腔镜下使用腔镜闭合切割器切断乙状结肠的近端和远端。自肛门插入腔内圆型吻合器 ,将降结肠与直肠吻合。经会阴于尿道膀胱与直肠之间造穴。将带血管蒂的乙状结肠牵入穴道 ,完成阴道成形。腹腔镜辅助下阴道成形中 ,腔镜闭合切割器切断乙状结肠的远端后 ,于左下腹壁做一辅助切口 ,将近端乙状结肠经此切口拉出至腹腔外。切断乙状结肠近端 ,将乙状结肠的远端开口缝合 2层 ,使之成盲端。近侧端开口置入吻合器之钉钻 ,再行荷包缝合送回腹腔 ,用吻合器行肠吻合。其余步骤同全腹腔镜手术步骤。术后根据临床检查或磁共振成像测量新成形阴道的长度和宽度。结果 :全腹腔镜手术新成形的阴道长 18cm ,宽 4cm。腹腔镜辅助手术新形成的阴道长 19cm ,宽 4cm。两例新形成的阴道黏膜湿润 ,呈粉红色。无术中和术后并发症的发生。结论 :经腹腔镜乙状结肠移植段的长度完全能达到开腹手术的要求。与开放手术比较 ,全腹腔镜乙状结肠代阴道手术在腹壁上不留手术瘢痕 ,美容效果理想。而腹腔镜辅助下阴道成形 ,虽腹壁留有小手术疤痕 ,但操作简便 ,手术时间短 ,手术费用低     

细胞凋亡及增殖细胞核抗原在肝癌组织中的表达及意义

目的探讨经肝动脉化疗栓塞(TACE)后肝癌细胞中增殖细胞核抗原(PCNA)广凋亡细胞比值与肝细胞肝癌分化程度的关系。方法应用原位末端标记法(TUNEL)及免疫组化双染色技术，对60例肝细胞肝癌石蜡包埋组织进行检测。结果不同分化程度癌组织中细胞凋亡和PCNA的阳性率不同。分化程度高，细胞凋亡阳性率高、PCNA阳性率偏低；分化程度低，细胞凋亡阳性率偏低、PCNA阳性率高。随分化程度的降低，PCNA广凋亡细胞的比值显著增加，两者有相关性。结论PCNA/凋亡细胞的比值可作为评估肝细胞肝癌分化程度的指标。