Apoptosis and oncosis in the early progression of left ventricular dysfunction in the cardiomyopathic hamster

The genetic defect in the cardiomyopathic (CM) hamster is a mutation in the glycoprotein-sarcoglycan (a component of the dystrophin-glycoprotein complex). Apoptosis has been identified in skeletal muscle of dystrophin-deficient mice, and therefore the role of myocardial apoptosis in relation to oncosis in causing myocardial necrosis was assessed at the onset of left ventricular (LV) dysfunction in CM hamsters. LV size and function were evaluated in normal and CM hamsters (CHF147 line) by echocardiography at 1, 2, 3, and 5 months (mo) of age. The decrease of LV fractional shortening was found to be most marked (45 %) between 1 and 2 mo of age. Apoptotic nuclei were identified at each time point using in situ end-labeling of DNA strand breaks (TUNEL), together with immunolabeling of myocytes; DNA fragmentation (laddering) and nuclear morphology were also assessed. Myocyte oncotic necrosis was assessed at 2 mo by Evans blue dye (EBD), wheat germ agglutinin, hematoxylin/eosin staining, and electron microscopy. Apoptotic nuclei were not detected in age-matched normal hamsters. In the CM hamsters apoptotic myocyte nuclei comprised an average of 0.041 % of myocyte nuclei between 1 and 5 mo, an increase at 2 mo (to 0.076 %) was not significant, and DNA laddering was not detected. The number of myocyte nuclei per unit area decreased by 32 % between 1 and 2 mo, and in 2 mo old CM hamsters myocardial staining with EBD was positive in 9.82 % of the myocardial cross sectional areas examined, most of which was consistent with sarcolemmal rupture and oncosis with inflammatory cell infiltration. It is concluded that myocyte oncosis provides the major mechanism for the decreased number of myocyte nuclei and the early decrease of cardiac function between 1 and 2 mo of age in the CM hamster, with only a small contribution of myocyte apoptosis. Received: 28 May 2001, Returned for revision: 8 June 2001, Revision received: 15 June 2001, Accepted: 18 June 2001     

Subareolar and peritumoral injection identify similar sentinel nodes for breast cancer

Background Sentinel lymph node (SLN) mapping with radioisotope and blue dye is rapidly becoming the standard of care for breast cancer. The optimal location for injection of radioisotope and blue dye is still being investigated. The goal of this study was to determine whether blue dye injection into the subareolar (SA) location localized the same sentinel nodes as the peritumoral (PT) location for patients with breast cancer. Methods Three hundred thirty-two patients with biopsy-proven operable breast cancer or ductal carcinoma in situ at two institutions underwent SLN mapping. Eighty-three patients had PT injection of blue dye (group 1), and 249 patients had SA injection of blue dye (group 2). All patients underwent PT injection of^99mTc-labeled sulfur colloid. Results The two groups were similar in age, previous biopsy type, and tumor size, location, and histology. The mean number of SLNs identified was 2.4 (range, 0–9) in group 1 and 2.5 (range, 0–11) in group 2. The SLN identification rate was 95% for group 1 and 97% for group 2. The isotope success rate was 94% for both groups. The blue dye success rate was 84% for group 1 and 90% for group 2. The isotope/blue dye concordance rate was 87% for group 1 and 90% for group 2. At a median follow-up of 28 months (range, 14 to 40), there were no axillary recurrences in any of the 332 patients. Conclusions These data suggest that delivery of mapping reagents in the SA and PT locations identifies similar lymph nodes. Because of simplicity and the similarity in node identification between SA and PT injection, further investigation of the SA site for delivery of SLN mapping reagents for breast cancer is warranted. Presented at the 54th Annual Cancer Symposium, Society of Surgical Oncology. Washington, DC, March 15–18, 2001.     

台盼蓝囊膜染色剂在白内障连续环形撕囊手术中的应用

目的研究台盼蓝囊膜染色剂在治疗白色白内障中,是否有助于连续环形撕囊的顺利完成及白内障手术的顺利进行。方法79例(80眼),随机分为2组,染色组40例(41眼),对照组39例(39眼),染色组使用台盼蓝囊膜染色剂,术中观察及对比前囊膜染色情况、连续环性撕囊成功率、晶状体后囊破裂及人工晶状体囊袋内植入情况,术后视力、前房炎症反应、角膜、人工晶状体有无蓝染及后囊混浊情况。并与对照组进行统计学分析。结果染色组的术中染色均匀,连续环形撕囊及人工晶状体囊袋内植入率为97.7%,晶状体后囊破裂率为2.44%,与对照组进行统计学分析有显著差异。术后追踪观察3个月,染色组术后视力好于对照组,前房炎症反应、晶状体后囊混浊2组无统计学差异。染色组术后角膜、人工晶状体未见蓝染,未见术中及术后并发症。结论台盼蓝囊膜染色剂目前是一种安全可靠的技术,手术中可以看清前囊,使连续环形撕囊顺利进行,人工晶状体稳定的位于囊袋内,增加了白色白内障手术的成功率。     

酸性染料比色法测定川贝母中贝母素甲含量

目的建立川贝母中贝母素甲含量测定方法。方法酸性染料比色法,在411 nm波长处测定吸收度计算含量。结果贝母素甲在14.06~126.54μg.mL-1呈线性关系,r=0.999 7,平均回收率为96.6%,RSD=1.6%。结论贝母素甲可作为川贝母的质量控制指标。     

Multiple-site optical recording of mouse brainstem evoked by vestibulocochlear nerve stimulation

We used optical imaging to investigate the mouse cochlear and vestibular nucleus in brainstem slices using a voltage-sensitive dye, RH 155. As a result, the spatiotemporal patterns of excitatory propagation were shown. These optical signals consisted of two components consisting of a spike-like fast signal and a long-lasting slow signal. All responses were abolished by tetrodotoxin. The slow signals were eliminated under a Ca(2+)-free solution. In addition, synaptic fatigue was also observed. The present study indicated the feasibility of optical recording for visually revealing the synaptic transmission in both the vestibular and cochlear nucleus.     

中华墨汁作为前哨淋巴结活检新型示踪剂的实验研究

目的探讨中华墨汁作为前哨淋巴结活检(sentinel lymph node biopsy,SLNB)示踪剂的价值。方法 42只雌性大耳自家兔随机分为7组,解剖第二对乳腺及同侧腋窝,从第二对乳头基底部注射1％异硫蓝(isosulfan blue,IB) 及配置消毒好的0.1％、1％、10％、20％、50％及原墨各0.1ml,观察淋巴链中腋淋巴结染色的时间、染色枚数及褪色时间。染色的第一枚淋巴结为前哨淋巴结(sentinel lymph node,SLN)。SLN于墨汁着色后5min、1h和两周各切取标本行病理组织学检查,实验动物在实验前及实验后两周处死前采血行常规及生化检查,处死后取心、肺、肝和肾做病理学检查。结果在染料到达SLN及下一站淋巴结的时间上,不同浓度墨汁间无明显差异(P＞0.05),但与1％IB比较均有明显延长(P＜ 0.05)。在检出SLN数目上,各组间无明显差异(P＞0.05)。在染色的程度上,0.1％墨汁染色的淋巴结颜色较浅,示踪效果较差。在褪色的时间上,1％IB染色的SLN平均33.9min明显褪色,而墨汁各组观察至实验后2周仍明显黑染。病理学动态观察淋巴结的染色过程,染色5min,SLN镜检见染色碳颗粒主要沉积于淋巴窦中,1h后逐渐被巨噬细胞吞噬。浓度在10％以下组织学观察效果良好,10％以上则因碳颗粒过多而影响了观察。实验动物生化检查各项指标及主要脏器病理学检查均未见异常。结论浓度为1％～10％中华墨汁SLN染色效果好,特异性较高,且不影响病理组织学观察,使用安全。1％～10％中华墨汁是一种具有潜在临床价值的新型SLNB染料示踪剂。     

白眉蝮蛇蛇毒糖基化蛋白的质谱分析

[目的]蛋白质组学方法分析和初步鉴定旅顺产白眉蝮蛇（Gloydius blomhoffi Brevicaudus）蛇毒中的糖蛋白。[方法]SDS-PAGE用于白眉蝮蛇粗毒蛋白质组份分离,糖蛋白凝胶荧光染料Pro-Q-Emerald染糖基化蛋白,采用胰蛋白酶酶解蛋白质,用反相C18-HPLC分离肽段混合物,用纳升电喷雾电离串联质谱（nESI-MS/MS）系统进行的质谱数据采集,蛋白质鉴定用Biowroks软件搜索NCBInr数据库完成。[结果]旅顺产白眉蝮蛇蛇毒L-氨基酸氧化酶、金属蛋白酶、谷氨酰环化酶、salmobin、纤溶酶原激活物、contortrixobin、磷脂酶A2,神经增长因子和较小分子量的L-氨基酸氧化酶被初步鉴定为糖蛋白,其匹配的肽段数分别为8、4、7、2、3、3、4、2和5个。L-氨基酸氧化酶的纯化与表征结果验证了其糖基化,并以多种糖基化形式存在。[结论]采用蛋白质组学手段从旅顺产白眉蝮蛇蛇毒中鉴定出了8种糖蛋白,该方法简便、快速、准确。     

Exchange transfusion in neutropenic septicemic neonates: effect on granulocyte functions

Depletion neutropenia caused by overwhelming bacterial infection is associated with fatal outcome and is an objective indicator of the severity of sepsis. Studies on controlled evaluation of exchange transfusion in the management of severe neonatal sepsis have not considered neutropenia as an inclusion critcrion, and randomized, controlled trials on evaluation of ncutrophil functions after exchange transfusion are scarce. This prompted us to carry out the present study. Septicemic neonates were enrolled if they had neutropenia and were randomized to undergo exchange transfusion (study group, n = 20) or not (controls, n= 10). Granulocyte functions were assessed using the nitro blue tetrazolium (NBT) reduction test and the staphylococcicidal index. Blood was drawn for granulocyte function tests once from controls and donors, and before, immediately after and 6 h after exchange transfusion in the study group. Mortality was 35% in the study group and 70% in controls. Gram-negative organisms accounted for 80%, in the study group and 90% in controls. Mean total leukocyte count and neutrophil count increased significantly immediately after exchange transfusion and 6 h later. Absolute band count decreased significantly immediately after exchange transfusion and incrcased 6 h later. NBT reduction in septicemic neonates in the study group, as wclras in controls. was significantly decreascd as compared to donor cells. NBT reduction improved significantly immediately after exchange transfusion and 6 h later. The valucs of the perccntage of viable staphylococci recovered from neutrophils also improved significantly immediately after exchange transfusion and 6 h later. We conclude that exchange transfusion with fresh whole blood in severe neonatal septicemia with neutropenia improves survival, increases the neutrophil count and cnhances neutrophil function.     

Optical Recordings of Ventricular Excitability of Frog Heart by an Extracellular Stimulating Point Electrode

To enhance understanding of the excitability of cardiac wusde during rest, an optical technique using the fluorescent voltage sensitive dye di-4-ANEPPS was used. Unlike conventional electrical recordings, optical recordings are free from electrical artifacts and. therefore, allow the observation of the transmembrane potential not only following the stimulation pulse, but also during the pulse itself Transmembrane potentials (V?_m) were recorded optically from frog ventricular epicardium in calcium containing Ringer's solution directly under an extracellular stimulating point electrode. Anodal and cathodal S stimuli were applied at rest. As observed by previous investigators, the post-pulse excitatory responses for cathodal pulses, compared with anodal pulses were greater. Changes in transmembrane potential (ΔV?_m) during the pulse were as expected for a passive cable only for low intensity pulses (< 4 × the cathodal threshold of excitation in diastole. CTE). However, at the higher intensities necessary to produce an excitatory response (> 6–8 × CTE), an “irregular” response in V?_m was observed—a reversal of the hyperpolarization during an anodal stimulus pulse and a reversal of the depolarization during a cathodal stimulus pulse. To elucidate further the biophysical basis for this behavior, ΔV?_m was mapped around the stimulating electrode. During stimulation, regions could be observed having a response with opposite polarity to that under the electrode (i.e. depolarization for an anodal pulse and hyperpolarization for a cathodal pulse). Removal of the bath solution or the addition of channel Mockers did not eliminate the occurrence of these regions. These regions appear to be the basis for the irregular behavior of ΔV?_m directly under the electrode as well as for anodal excitation.     

Characterization of gap junctions between osteoblast-like cells in culture

Summary The structure of gap junctions in osteoblast-like cells (OBs) and the connexins (cx) that build up these structures were characterized by ultrastructural, immunocytochemical, and molecular techniques. Ultrastructural studies revealed numerous gap junctions which were mostly located on processes of neighboring cells. Immunofluorescence labeling using two different antibodies (specific to mouse live cx26 and cx32 and to a peptide-specific rat heart gap junction protein cx43) gave evidence that in OBs, gap junctions consist mainly of cx43. The presence of cx43 in cultured OB was also confirmed by Western blot analysis. Dye-coupling with Lucifer yellow led to a staining of up to 30 neighboring cells. Parallel intracellular recordings showed that membrane potential amplitude changes (4–5 mV) are typically related to those in the coupled cells. Thus, there is morphological and functional evidence for intercellular communication between OB in culture. OBs in culture express the same connexins as observed in vivo and may serve as a model to investigate electrophysiological events in response to different stimulation signals.