钛制空心钉结合张力带内固定手术治疗髌骨骨折

目的探讨膝关节直切口下空心拉力螺钉张力带钛丝内固定治疗髌骨骨折的优缺点及手术适应证.方法对27例髌骨骨折患者进行回顾性分析:横行骨折11例、粉碎骨折15例、陈旧性骨折1例均采用张力带钛丝结合2枚钛制空心拉力螺钉固定.结果所有患者随访3~20个月,骨折全部愈合,按胥少汀评分标准评估,优19例,良6例,可2例,优良率92%.结论采用钛制空心螺钉 张力带内固定技术治疗髌骨骨折固定牢固、疗效确切,适用于髌骨横行、粉碎性骨折.     

自制裸磁珠对常见食源性致病菌吸附性能的研究

目的：研究自制裸磁珠对常见食源性致病菌和卫生指示菌的吸附性能，摸索从样品中快速分离和浓集细菌的方法。方法：试验裸磁珠对细菌的吸附性能，摸索温度和样品成分对其吸附性能的影响。结果：自制裸磁珠在37℃对常见食源性致病菌和卫生指示菌有很强的吸附，吸附率均高于97％。食品成分对其吸附有一定影响，吸附率最低为58．42％。结论：自制裸磁珠可望用于环境和食品样品中多种细菌的非特异性吸附分离和浓集，值得进一步研究和推广。     

不同表面处理的种植入早期表面沉积物的分析研究

目的：比较两种不同表面处理的种植体在植入早期表面沉积物的差异及其骨组织反应。方法：将表面经双重酸-双氧水热处理和双重酸处理的种植体分别植入兔子胫骨内，然后，采用带能谱分析的扫描电镜观测2、4、8周带种植体的骨组织。结果：植入2周后在两组种植体表面均沉积富含钙磷层；4周时这层结构大部分消失，但双重酸-双氧水-热处理组可见较多的骨生成细胞附着在种植体表面并形成新骨。8周时两组种植体表面均附着一些新骨，但以双重酸-双氧水-热处理组相对较多。结论：两组种植体在植入早期表面均可形成富含钙磷层。     

Sustained effect of inhaled diesel exhaust particles on T-lymphocyte-mediated immune responses against Listeria monocytogenes.

Studies have shown that exposure to diesel exhaust particles (DEP) suppresses pulmonary host defense against bacterial infection. The present study was carried out to characterize whether DEP exposure exerts a sustained effect in which inhaled DEP increase the susceptibility of the lung to bacterial infection occurring at a later time. Brown Norway rats were exposed to filtered air or DEP by inhalation at a dose of 21.2 +/- 2.3 mg/m3, 4 h/day for 5 days, and intratracheally instilled with saline or 100,000 Listeria monocytogenes (Listeria) 7 days after the final DEP exposure. Bacterial growth and cellular responses to DEP and Listeria exposures were examined at 3 and 7 days post-infection. The results showed that inhaled DEP prolonged the growth of bacteria, administered 7 days post DEP exposure, in the lung as compared to the air-exposed controls. Pulmonary responses to Listeria infection were characterized by increased production of interleukin (IL)-1beta, tumor necrosis factor (TNF)-alpha, IL-12, and IL-10 by alveolar macrophages (AM) and increased presence of T lymphocytes and their CD4+ and CD8+ subsets in lung draining lymph nodes that secreted elevated levels of IL-2, IL-6, IL-10, and interferon (IFN)-gamma. Diesel exhaust particles were found to inhibit Listeria-induced production of IL-1beta and TNF-alpha, which are responsible for the innate immunity, and IL-12, which initiates the development of T helper (Th)1 responses, but enhance Listeria-induced AM production of IL-10, which prolongs Listeria survival in these phagocytes. The dual action of DEP on AM production of IL-12 and IL-10 correlated with an inhibition of the development of bacteria-specific T lymphocytes by DEP. Cytokine production by lymphocytes from DEP- and Listeria-exposed rats showed a marked decrease in the production of IL-2, IL-10, and IFN-gamma compared to Listeria infection alone, suggesting either that DEP inhibit the production of cytokines by lymphocytes or that these lymphocytes contained T-cell subsets that are different from those of Listeria infection alone and less effective in mediating Th1 immune responses. This study demonstrates that inhaled DEP, after a 7-day resting period, increase the susceptibility of the lung to bacterial infection occurring at a later time by inhibiting macrophage immune function and suppressing the development of T-cell-mediated immune responses. The results support the epidemiological observations that exposure to DEP may be responsible for the pulmonary health effects on humans.     

Exposure of brown Norway rats to diesel exhaust particles prior to ovalbumin (OVA) sensitization elicits IgE adjuvant activity but attenuates OVA-induced airway inflammation.

Exposure to diesel exhaust particles (DEP) during the sensitization process has been shown to increase antigen-specific IgE production and aggravate allergic airway inflammation in human and animal models. In this study, we evaluated the effect of short-term DEP exposure on ovalbumin (OVA)-mediated responses using a post-sensitization model. Brown Norway rats were first exposed to filtered air or DEP (20.6 +/- 2.7 mg/m3) for 4 h/day for five consecutive days. One day after the final air or DEP exposure (day 1), rats were sensitized with aerosolized OVA (40.5 +/- 6.3 mg/m3), and then again on days 8 and 15, challenged with OVA on day 29, and sacrificed on days 9 or 30, 24 h after the second OVA exposure or the final OVA challenge, respectively. Control animals received aerosolized saline instead of OVA. DEP were shown to elicit an adjuvant effect on the production of antigen-specific IgE and IgG on day 30. At both time points, no significant airway inflammatory responses and lung injury were found for DEP exposure alone. However, the OVA-induced inflammatory cell infiltration, acellular lactate dehydrogenase activity and albumin content in bronchoalveolar lavage (BAL) fluid, and numbers of T cells and their CD4+ and CD8+ subsets in lung-draining lymph nodes were markedly reduced by DEP on day 30 compared with the air-plus-OVA exposure group. The OVA-induced nitric oxide (NO) in the BAL fluid and production of NO, interleukin (IL)-10, and IL-12 by alveolar macrophages (AM) were also significantly lowered by DEP on day 30 as well as day 9. DEP or OVA alone decreased intracellular glutathione (GSH) in AM and lymphocytes on days 9 and 30. The combined DEP and OVA exposure resulted in further depletion of GSH in both cell types. These results show that short-term DEP exposure prior to sensitization had a delayed effect on enhancement of the sensitization in terms of allergen-specific IgE and IgG production, but caused an attenuation of the allergen-induced airway inflammatory responses.     

Histological evidence concerning the osseointegration of titanium implants in the fractured rabbit femur

Stabilization of the broken bone is achieved using biocompatible materials. Since histology is still considered the gold standard technique for the assessment of bone formation around metallic implants, this report investigated the titanium implant integration in the accidentally broken bone in rabbits. The experimental protocol was reviewed and approved by the Ethical Committee of the Faculty of Medicine and Pharmacy Oradea, Romania. Holes were drilled in the diaphysis of the femur, and titanium implants were inserted in the created bone defect. In two subjects, fractures occurred on days two and three after the metallic alloy implantation. The other two rabbits presented no fractures following the surgical procedure. The rabbits were euthanized and the bones (with metallic implants) were harvested for histopathological investigation. Following decalcification, the bone samples were processed using the standard paraffin technique and stained by Goldner’s trichrome procedure. In subjects with a perfect immobilization of the titanium implants, the osseointegration occurred with minimal callus formation (i.e. primary cortical healing). In rabbits with bone fractures, the callus was more exuberant. A progressive replacement of the granulation tissue with hyaline cartilage and woven bone occurred soon after. The former aspects suggested an indirect metaplasia in the created callus. In all subjects, no inflammatory cells were identified in the created callus. The bone regeneration occurred either by primary cortical healing (in perfectly immobilized titanium implants) or by a process similar to the endochondral ossification (in poorly immobilized titanium implants following accidental post-implantation bones fracture).     

Preclinical refinements of a broadly protective VLP-based HPV vaccine targeting the minor capsid protein,L2

An ideal prophylactic human papillomavirus (HPV) vaccine would provide broadly protective and long-lasting immune responses against all high-risk HPV types, would be effective after a single dose, and would be formulated in such a manner to allow for long-term storage without the necessity for refrigeration. We have developed candidate HPV vaccines consisting of bacteriophage virus-like particles (VLPs) that display a broadly neutralizing epitope derived from the HPV16 minor capsid protein, L2. Immunization with 16L2 VLPs elicited high titer and broadly cross-reactive and cross-neutralizing antibodies against diverse HPV types. In this study we introduce two refinements for our candidate vaccines, with an eye towards enhancing efficacy and clinical applicability in the developing world. First, we assessed the role of antigen dose and boosting on immunogenicity. Mice immunized with 16L2-MS2 VLPs at doses ranging from 2 to 25 μg with or without alum were highly immunogenic at all doses; alum appeared to have an adjuvant effect at the lowest dose. Although boosting enhanced antibody titers, even a single immunization could elicit strong and long-lasting antibody responses. We also developed a method to enhance vaccine stability. Using a spray dry apparatus and a combination of sugars & an amino acid as protein stabilizers, we generated dry powder vaccine formulations of our L2 VLPs. Spray drying of our L2 VLPs did not affect the integrity or immunogenicity of VLPs upon reconstitution. Spray dried VLPs were stable at room temperature and at 37 °C for over one month and the VLPs were highly immunogenic. Taken together, these enhancements are designed to facilitate implementation of a next-generation VLP-based HPV vaccine which addresses U.S. and global disparities in vaccine affordability and access in rural/remote populations.     

Maternal Exposure to Trichloroethylene in Drinking Water and Birth-Weight Outcomes

An ecological epidemiological study was conducted with data obtained from an environmental dose-reconstruction study and the Arizona Birth Information Tapes. Before 1981, a portion of the city of Tucson water-distribution system was contaminated with trichloroethylene (i.e., < 5 micrograms per liter of water to 107 micrograms per liter of water). Target and comparison populations were selected with a Geographic Information System. Logistical-regression analysis revealed an association between maternal exposure to trichloroethylene via drinking water and very-low-birth-weight babies (i.e., < 1,501 grams) (odds ratio = 3.3; 95% confidence interval = 0.5, 20.6; and Wald chi-square p value = 0.2). No association was found between maternal exposure to trichloroethylene via drinking water and low birth weight or full-term low-birth-weight infants (gestational period > 35 wk and < 46 wk).     

Intercorrelations of lipoprotein subfractions and their covariation with lifestyle factors in healthy men

So far, little is known about the effect of nutrition and lifestyle on the composition of circulating lipoprotein subfractions. In the current study, we measured the correlations among physical activity, nutrient intake, smoking, body-mass index (BMI), and age with the concentration of triglycerides, cholesterol, phospholipids, and apolipoproteins (ApoA1, ApoA2 and ApoB) in subfractions of LDL and HDL in 265 healthy working men. Concentrations of cholesterol, phospholipids, and ApoB in small, dense atherogenic LDL particles (sdLDL) correlated negatively (p<0.001) with those of cholesterol, phospholipids, and ApoA1 in HDL2, respectively. Age correlated positively with sdLDL while increasing BMI correlated with an atherogenic shift of cholesterol, phospholipids, and ApoB from large, buoyant LDL (lbLDL) to sdLDL and decreasing concentrations of HDL2 constituents. Physical activity and alcohol intake correlated negatively with sdLDL constituents and positively with HDL2 components. Consumption of monounsaturated fatty acids (MUFA) correlated with a lower ratio of sdLDL to HDL2 cholesterol. A favorable lipoprotein subfraction profile linked to a reduced risk of cardiovascular disease in men was associated with physical activity, moderate alcohol consumption, and dietary intake of MUFA, which might be exploited in future interventions for prevention of age- and BMI-associated atherogenic shifts of lipoprotein subfractions.     

Exposure to total particulate matter obtained from combustion of diesel vehicles (EURO 3 and EURO 5): Effects on the respiratory systems of emphysematous mice

Air pollution has association with chronic obstructive pulmonary disease (COPD) and reduced life expectancy. This study investigated the deleterious effects caused by tobacco smoke and diesel exhaust particles (DEP) from vehicles operating under EURO 3 and EURO 5 standards. Experiments were carried out on C57BL/6 mice divided into six groups: control group, group exposed to cigarette smoke (CS), two groups exposed to DEP (AAE3 and AAE5), and two groups exposed to tobacco smoke and vehicle DEP (CSE3 and CSE5). Results showed that, when compared to AA, groups AAE3 and AAE5 showed changes in respiratory mechanics, and that DEP originating from EURO 5 diesel vehicles was less harmful when compared to DEP originating from EURO 3 diesel vehicles. Analyses of groups CSE3 and CSE5 revealed increased inspiratory capacity and decreased tissue elastance, when compared to their respective controls, suggesting an exacerbation of changes in respiratory system mechanics compatible with COPD development.