Evaluation of filling materials in membrane‐protected bone defects. A comparative histomorphometric study in the mandible of miniature pigs.

In recent years, bone grafts and bone substitutes have been increasingly utilized underneath barrier membranes to optimize the treatment outcome of bone reconstructive therapy for defects in the alveolar process. In the present study, 4 different filling materials were evaluated in bone defects of similar dimensions in the mandible of miniature pigs. Blood clots and autografts were used as controls. The defects were covered with barrier membranes and allowed to heal for 4, 12 or 24 weeks. Histologic examination demonstrated that bone repair progressed through a programmed sequence of maturation steps closely resembling the pattern of bone development and growth regardless of whether bone grafts or substitutes were present or not. Histomorphometric analysis showed that autologous bone grafts (autografts) had the best osteoconductive properties during the initial healing period, with 39% of newly formed bone inside the membrane-covered defects at 4 weeks of healing. In addition, 87% of the graft surfaces were already covered by bone at this time. Both values were significantly higher for autografts than for the 4 alternative bone fillers (P < or = 0.05). At 12 weeks, these differences were no longer apparent, with all 5 filling materials showing similar values. Among the tested bone substitutes, tricalcium phosphate (TCP) showed a significantly higher percentage of bone fill at 24 weeks of healing. It can be concluded that sites filled with autografts clearly demonstrated the best results underneath barrier membranes in the early phase of healing. As far as degradation and substitution are concerned, TCP showed the most promising results. This filler, however, needs to be tested further in a more demanding animal model. Less favorable results were obtained for coral-derived hydroxyapatite granules and for demineralized freeze-dried bone allografts.     

空管药物疗法治疗牙髓病和根尖周病疗效观察

用ＳＭＴＤ复合药物对牙髓病和根尖周病实施空管药物疗法。７８例１０３颗获得完整随访资料患牙经两年观察，９２．２％治愈率。文章介绍了治疗方法，讨论了空管药物疗法的愈合机理、优点、失败原因及其预防措施。     

Flow Cytometric Analysis of Lymphocyte Subsets of Mice Maintained on an Ethanol-Containing Liquid Diet

Alcoholic patients often have impaired immune function, yet little is known about the precise mechanism(s) of this impairment. We have previously shown that ethanol consumption by mice alters copolymer-specific humoral and cellular immune responses. In this study, we asked whether alcohol consumption by mice would phenotypically alter lymphocyte populations. Female C57BL/6 mice were fed a nutritionally complete liquid diet containing 35% ethanol-derived calories for up to 8 days. As controls, mice either were fed a liquid control diet that isocalorically substitutes sucrose for ethanol or remained on a standard solid diet and water ad libitum. Although mice fed ethanol-containing liquid or pair-fed control liquid diets have decreased numbers of spleen cells compared with solid diet controls, only the ethanol-containing diet allowed normally nonresponder C57BL/6 spleen cells to make antibody responses to the poly(Glu⁵⁰Tyr⁵⁰) synthetic copolymer antigen. Flow cytometric analysis of splenic lymphocyte populations of mice on the ethanol-containing diet shows an increase in the relative proportion of T-lymphocytes as compared with mice on either solid or liquid control diets. No such change is seen for either B-cell or natural killer cell populations in these same mice. Both liquid control and liquid ethanol diets caused a slight decrease in the CD4:CD8 ratios of splenic T-lymphocytes. We see the relative percentage of T-cells bearing the αβ-cell receptor (TcR) increases in the spleens of liquid ethanol diet mice; a smaller increase TcRαβ usage is seen in the spleens of liquid control mice, compared with solid diet mice. Flow cytometric analysis shows that little, if any, difference exists in TcRγδ expression between the liquid ethanol and either the liquid control or solid diet groups. Preliminary analysis of TcRαβ subsets suggest that ethanol increases the percentage of T-cells expressing Vβ5 and Vβ8, and decreases the percentage of Vβ11 expressing cells. These findings suggest that, in addition to modifying the immune response, ethanol alters the phenotypic expression of lymphocyte subsets.     

丁卡因对人红细胞膜乙酰胆碱酯酶的抑制作用及其与膜脂的关系

本文以人红细胞膜为材料，应用荧光探针（ANS）及酶学研究方法，研究了丁卡因对AchE及红细胞膜脂之间的关系。结果显示，丁卡因对红细胞膜AchE有明显抑制作用，其半数抑制浓度为525μmol/L。丁卡因还能増加膜-ANS复合物荧光强度，双倒数及Scatchard作图分析表明，其使膜ANS复合物荧光强度增强的原因并非ANS荧光量子产率的改变，而是膜上ANS结合数量增加所致，这一效应与其时膜流动性影响是一致的。     

Transjugular intrahepatic cavoportal shunt for Budd–Chiari syndrome

Budd–Chiari syndrome (BCS) is characterized by obstruction of the hepatic venous outflow tract. Therapeutic options for BCS are limited. We report a case of a 21-year-old woman with protein S and C deficiency with gross ascites. Treatment with transjugular intrahepatic portosystemic shunt (TIPS) was attempted, which revealed occluded hepatic veins, so transcaval TIPS was performed. No serious procedure-related complication occurred. After successful shunt creation, the patient's symptoms subsided and she was discharged and followed up for 6 months.     

Open mesh versus non-mesh repair of groin hernia meta-analysis of randomized trials leased on individual patient data

Abstract Background. The EU Hernia Trialists Collaboration was established to provide reliable evaluation of newer methods of groin hernia repair. It involved 70 investigators in 20 countries. Materials and methods. Twenty eligible trials (5016 participants) of open mesh vs. non-mesh groin hernia repair were identified. Meta-analysis was performed using raw individual patient data where possible. Results. Fewer hernia recurrences were reported after mesh repair. There were no clear differences between mesh and non-mesh groups in complications. Overall, those in the mesh groups had a shorter hospital stay, quicker return to usual activities and less frequent persisting pain, but individual trial results varied. Conclusions. The review provides strong evidence that open mesh repair is associated with a reduction in the risk of recurrence of between 50% and 75%. There is also some evidence of quicker recovery and of lower rates of persisting pain following open mesh repair. Electronic Publication     

Mutational analysis of immunoglobulin E-binding epitopes of β-casein and β-lactoglobulin showed a heterogeneous pattern of critical amino acids between individual patients and pooled sera

BACKGROUND: For immunotherapeutic approaches, 'critical' amino acids (AAs) within allergenic epitopes are replaced with alternate AAs to eliminate IgE antibody binding. OBJECTIVE: To determine the critical AAs for IgE binding in beta-casein and beta-lactoglobulin (BLG). METHODS: Peptides of 10-14 AAs in length were synthesized on a derivatized cellulose membrane with single AA substitutions (alanine or glycine) at each position. Membranes were incubated with a pool of sera from 15 cow's milk-allergic patients and individual sera from six of the 15 patients. In cases where no decrease in binding occurred with a single AA substitution, peptides with two AA substitutions were generated and labelled. RESULTS: Using pooled patient sera, single AA substitutions led to complete elimination of binding to six of 11 peptides for beta-casein and to all six peptides for BLG. Substituting two AAs led to an elimination of binding to four of the remaining five beta-casein epitopes. However, in three of the 11 modified beta-casein peptides and five of the six BLG peptides, no decrease in IgE binding occurred in at least one individual patient. For these patients, critical AAs other than those defined by the patient serum pool were identified, indicating a heterogeneous pattern of IgE recognition. CONCLUSION: These results indicate that AAs critical for IgE binding are more heterogeneous than initially defined by pooled milk-allergic patient sera. For future immunotherapeutic interventions with mutated peptides, critical AAs should also be identified with individual patient sera to account for heterogeneity of IgE binding between patients.     

Studies on mutants deficient in the photosystem I reaction centers in Chlamydomonas reinhardtii

Summary Genetic analysis of 25 nuclear mutants defective in the chlorophyll-protein complex CP1 was undertaken. The mutants belong to 13 complementation groups scattered throughout the nuclear genome. All these mutants lack the apoprotein of CP1 and, in addition, a specific set of six low molecular weight thylakoid polypeptides. System I particles obtained by treating WT thylakoid membranes with detergent specifically contain those polypeptides which the mutants lack. These observations suggest that a particular sub-structure of the thylakoid membrane associated with the photosystem I activity is missing from all 25 mutants studied, and that this general phenotype can result from mutation at any one of several unlinked Mendelian loci.     

Temperature stabilizing effect of tocopherol on rhodopsin in the pressure of fatty acids studied by differential scanning calorimetry

Institute of Cytology, Academy of Sciences of the USSR. I. M. Sechenov Institute of Evolutionary Physiology and Biochemistry, Academy of Sciences of the USSR, Leningrad. Institute of Physiology, Bulgarian Academy of Sciences, Sofia. (Presented by Academician of the Academy of Medical Sciences of the USSR Yu. A. Vladimirov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 108, No. 8, pp. 160–171, August, 1989.