超声对女婴幼儿腹股沟疝伴卵巢嵌顿的早期诊断及鉴别

目的 探讨超声对女性婴幼儿腹股沟疝伴卵巢嵌顿的早期诊断及鉴别.方法 分析经手术证实的女婴腹股沟疝伴或不伴卵巢嵌顿患者的二维及彩色多普勒超声图像特征.结果 超声诊断的28例病例中,12例卵巢嵌顿超声表现为典型的卵巢声像图,1例卵巢坏死超声表现为混合性肿块.结论 超声检查女性婴幼儿斜疝伴卵巢嵌顿的诊断符合率高,应作为首先检查方法之一.     

Protein Phosphatases Decrease Sarcoplasmic Reticulum Calcium Content by Stimulating Calcium Release in Cardiac Myocytes

Phosphorylation/dephosphorylation of Ca²⁺ transport proteins by cellular kinases and phosphatases plays an important role in regulation of cardiac excitation−contraction coupling; furthermore abnormal protein kinase and phosphatase activities have been implicated in heart failure. However, the precise mechanisms of action of these enzymes on intracellular Ca²⁺ handling in normal and diseased hearts remains poorly understood. We have investigated the effects of protein phosphatases PP1 and PP2A on spontaneous Ca²⁺ sparks and SR Ca²⁺ load in myocytes permeabilized with saponin. Exposure of myocytes to PP1 or PP2A caused a dramatic increase in frequency of Ca²⁺ sparks followed by a nearly complete disappearance of events. These effects were accompanied by depletion of the SR Ca²⁺ stores, as determined by application of caffeine. These changes in Ca²⁺ release and SR Ca²⁺ load could be prevented by the inhibitors of PP1 and PP2A phosphatase activities okadaic acid and calyculin A. At the single channel level, PP1 increased the open probability of RyRs incorporated into lipid bilayers. PP1-medited RyR dephosphorylation in our permeabilized myocytes preparations was confirmed biochemically by quantitative immunoblotting using a phosphospecific anti-RyR antibody. Our results suggest that increased intracellular phosphatase activity stimulates RyR-mediated SR Ca²⁺ release leading to depleted SR Ca²⁺ stores in cardiac myocytes.     

骨组织工程支架材料聚磷酸钙的体外可控降解规律研究

为研究骨组织工程支架材料聚磷酸钙的体外降解机理和可控降解规律,本文通过分别控制保温时间和烧结温度得到不同工艺条件的聚磷酸钙材料样品,采用X射线衍射(XRD)表征不同制备工艺材料的物象结构。以三羟甲基氨基甲烷(TRIS)氯化氢缓冲溶液为降解介质,通过失重法、钼蓝分光光度法分析材料的降解性能。用扫描电镜(SEM)观察材料在降解前后的表面形貌,并建立数学模型来描述材料的降解速率和制备工艺的内在关系。结果表明,同等保温时间下,烧结温度越高,降解速度越快,而同等烧结温度下,保温时间在3～7h之间,保温5h的材料显示了较好的降解性;数学模型得出降解液中磷酸根浓度(y)和时间(t)的关系为y=a(1-e-bt)。     

骨组织工程支架材料聚磷酸钙生物陶瓷研究进展

为修复创伤及病理因素导致的骨缺损,骨组织工程是一项迅速发展、不断革新的课题。多孔聚磷酸钙生物陶瓷是可吸收生物陶瓷的一种,具有良好的生物相容性以及可降解性,在骨组织工程中日益被人们所认识。骨组织工程中细胞生长速率与材料的降解速率相匹配一直是有待解决的问题,聚磷酸钙由于具有独特的结构及降解性能,因此有望解决这个问题。本文对作为骨组织工程支架材料之一的聚磷酸钙生物陶瓷的理化性质、制备方法、研究进展、骨结合机理等进行了综述,并对其研究和发展作出了展望。     

兔肺动脉高压时肺组织中内皮素和鸟苷环－磷酸含量的变化及意义

１１只兔进行从降主动脉至左肺动脉的分流手术，观察三个月后形成了左侧肺动脉高压。取左、右肺组织测定内皮素（ＥＴ）和ｃＧＭＰ，发现左侧肺组织中ＥＴ含量较右侧为高，而ｃＧＭＰ则较右侧为低，两侧比较差异显著。因组织中ｃＧＭＰ的含量间接反映了内皮舒缩血管因子（ＥＤＲＦ）的含量，故认为肺高压时肺组织中ＥＴ分泌增加和ＥＤＲＦ分泌减少。两者的变化在肺高压的形成过程中可能起重要作用。     

Fluid Flow-Induced Calcium Response in Early or Late Differentiated Osteoclasts

Intracellular calcium oscillation caused by receptor activator of nuclear factor kappa-B ligand has been demonstrated to promote the differentiation of osteoclasts. Osteoclasts are recruited on the surface of trabeculae, and are exposed to fluid flow caused by the deformation of the bone matrix. However, the roles of fluid shear stress (FSS) on calcium response during the differentiation process of osteoclasts are still unknown. In the current study, the formation of tartrate-resistant acid phosphatase-positive, multinucleated osteoclasts from RAW264.7 macrophage cells were induced by co-culturing them with the conditioned medium from MC3T3-E1 osteoblasts. The in situ observations showed a high correlation between the area and the nuclear number of osteoclasts. The cells were stimulated by FSS at different levels (1 or 10 dyne/cm(2)) before (0 day) or after being induced for 4 or 8 days. The mechanically-induced calcium response was recorded and analyzed. The results indicated a different property of calcium oscillation for the osteoclasts in different fusion stages (i.e., more calcium-responsive peaks appeared in small osteoclasts than those in the larger ones). The rates of calcium influx decreased and the time of recovery in osteoclast cytosol increased along with the fusion of osteoclasts. In addition, increasing the FSS level enhanced the calcium oscillation of osteoclasts at early induction (4 days). However, this effect was weakened at the late induction (8 days). The present work could help provide understanding regarding the mechanism of the involvement of calcium in mechanically induced bone remodeling.     

Ultrastructural Changes in Muscular Dystrophy: I. Cardiac Tissue of Piglets Deprived of Vitamin E and Selenium

The ultrastructure of cardiac tissue from neonate, 3-, 6-, 8-, and 12-week-old piglets, born of vitamin E- and selenium-deprived sows was studied. A progression of lesions occurred in nonmuscular components of this tissue; the first lesion appeared in connective tissue elements. Fibroblasts and the extracellular compartment appeared most severely altered in the neonate, and progressive vascular damage was very evident from 3 to 12 weeks of age. Similarly, neuronal elements appear altered at 3 weeks and were almost nonevident in areas showing marked lesions at 8 and 12 weeks. Fairly extensive alterations were evident in all of these elements before any marked changes become evident in the muscle. The relevance of these observations is discussed in relation to the etiology of the disease.     

Tissue microarrays, or the advent of chips in pathology

Tissue microarray technology is a new method used to analyze several hundred tumor samples on a single slide allowing high throughput analysis of genes and proteins on a large cohort. The method consists to core tissues from paraffin-embedded tissue donor blocks and placing them into a single paraffin block. Despite the low amount of tissue analyzed by tissue microarray, different studies have demonstrated a high concordance of protein expression between this technique and the conventional tissue sections.     

Effect of Richlocaine on Proliferative Activity of Osteoblasts and Intracellular Calcium Content in Rats

We studied the effect of local anesthetic richlocaine on proliferation and intracellular calcium content in cultured osteoblasts from rat parietal bone. In a concentration of 1 mg/ml this drug produced a cytotoxic effect on osteoblasts. In concentrations of 0.01 and 0.001 mg/ml richlocaine in the absence and presence of subtoxic dose of sodium cyanide (0.2 mM) increased the number of osteoblasts by 15.4 and 36.6 or 13.8 and 38.6%, respectively. In a concentration of 1 mg/ml, richlocaine increased the content of cytosolic calcium in osteoblasts by 105%. These effects of richlocaine in low concentrations (0.01 and 0.001 mg/ml) can be related to stimulation of metabolic processes in osteoblasts.     

大鼠肾缺血与再灌时近曲小管上皮细胞内钙含量变化

本实验采用细胞化学方法结合EDX微区分析及生化测试方法，从细胞水平研究了大鼠肾近曲小管上皮细胞内钙含量在缺血-再灌流损伤过程中的改变情况，并探讨了其机理。结果表明：缺血1h，可致细胞内钙含量增高，质膜Ca2 -ATPase活性下降；膜通透性无明显变化。再灌流期，细胞内钙含量持续增高；质膜Ca2 －ATPase活性在再灌流早期（2～4h）基本恢复至正常，在再灌流晚期（12～24h）下降；再灌流期膜通透性逐渐增大。肾小管上皮细胞内钙含量增加在缺血期、再灌流早期及晚期某机制并不相同。     

Tissue concentration of doxorubicin (adriamycin) in mouse pretreated with alpha-tocopherol or coenzyme Q10

The tissue concentration of doxorubicin (adriamycin; ADM) and its major metabolite (aglycone I) was examined in mice pretreated with alpha-tocopherol (VE) or coenzyme Q10 (CoQ). In VE-pretreated group, the concentrations of aglycone I of the liver (1, 3 and 5 h after the administration), kidney (1 and 3h) and heart (3h) were significantly higher than those in the saline group. The clinical application of VE or CoQ concomitant with anti-tumor drugs especially ADM, requires caution.     

吻合血管的狗自体腹股沟淋巴结移植的研究

在7例杂种狗中进行了吻合血管的腹股沟淋巴结自体移植。动静脉吻合口的通畅率为100%;淋巴管造影表明移植的淋巴结在术后4周内均已成活;成活的淋巴结具有正常的组织结构。讨论了手术注意事项和术后观察手段。     

Hyperbranched Polyesters with Carboxylic or Sulfonic Acid Functional Groups for Crystallization Modification of Calcium Carbonate

Hyperbranched aliphatic polyesters functionalized with carboxylic or sulfonic acid groups have been synthesized and employed as crystallization modifiers for calcium carbonate. The functionalized polyesters exhibit remarkable polymorph selectivity and morphology control. Stable spherical vaterite particles of diameter less than 10 µm with narrow size distribution were easy to produce on a large scale. With an increase in the concentration and monomer/core ratio of the polyester, the vaterite content increases accordingly with promoted morphology control to monodisperse spheres. The CaCO₃ concentration and the initial pH can also influence the morphology and polymorphism of the produced calcium carbonate. Under certain conditions, well‐defined core‐shell structured vaterite spheres are obtained with obvious radial organization by nano‐aggregation of about 70 ± 10 nm crystallites, which may mediate and combine the nano‐aggregation and crystal growth formation mechanism of vaterite polymorph.

     

Tissue reactions to epoxy-crosslinked porcine heart valves post-treated with detergents or a dicarboxylic acid

Calcification limits the long-term durability of xenograft glutaraldehyde (GA)-crosslinked heart valves. Previously, a study in rats showed that epoxy-crosslinked heart valves reduced lymphocyte reactions to the same extent as the GA-crosslinked control and induced a similar foreign-body response and calcification reaction. The present study was aimed at reducing the occurrence of calcification of epoxy-crosslinked tissue. Two modifications were carried out and their influence on cellular reactions and the extent of calcification after 8 weeks' implantation in weanling rats was evaluated. First, epoxy-crosslinked valves were post-treated with two detergents to remove cellular elements, phospholipids and small soluble proteins, known to act as nucleation sites for calcification. The second approach was to study the effect of the impaired balance between negatively and positively charged amino acids by an additional crosslinking step with a dicarboxylic acid. The detergent treatment resulted in a washed-out appearance of especially the cusp tissue. With the dicarboxylic acid, both the cusps and the walls had a limited washed-out appearance. The wall also demonstrated some detachment of the subendothelium. After implantation, both detergent and dicarboxylic acid post-treatment histologically resulted in reduced calcification at the edges of cusps and walls. However, total amounts of calcification, measured by atomic emission spectroscopy, were not significantly reduced. Data concerning the presence of lymphocytes varied slightly, but were in the same range as the GA-crosslinked control, i.e., clearly reduced compared with a noncrosslinked control. It is concluded that both the double detergent and the dicarboxylic acid post-treatment of epoxy-crosslinked heart valve tissue do not represent a sound alternative in the fabrication of heart valve bioprostheses.