Adenovirus-mediated human β-nerve growth factor gene transfer has a protective effect on cochlear spiral ganglion after blast exposure

Objective：To study whether adenovirus-mediated human β-nerve growth factor （Ad-hNGFβ） gene has any protective effect on blast hearing impairment. Methods：Deafness was induced by blast exposure （172.0 dB） in 30 healthy guinea pigs. On day 7 of blast exposure, Ad-hNGFβ was infused into the perilymphatic space of 20 animals as the study group （hNGFβ group）, and artificial perilymph fluid （APF） was infused into the perilymphatic space of the other 10 animals as the control group. At weeks 1, 4 and 8 after blast exposure, the animals were sacrificed and the cochleae were removed for immunohistochemical and HE stainings. Results： Expression of Ad-hNGFβ protein was detected in each turn of the cochlea at the 1st week, with almost equal intensity in all turns. At the 4th week, the reactive intensity of the expression of Ad-hNGFβ protein decreased. At the 8th week, no expression was detectable. The results of HE staining showed that the amount of spiral ganglions in hNGFβ group was significantly greater than that of the control group at week 4 （P〈0.01）. Conclusion： Ad-hNGFβ can be expressed at a high level and for a relatively long period in the blast impaired cochlea, suggesting that Ad-hNGFβ has a protective effect on cochlear spiral ganglion cells after blast exposure and the efficient gene transfer into cochlea had been achieved without toxicity.     

Effects of occupational exposure and smoking on respiratory symptomatology and PFT in healthy panelists and COPD patients

A panel of 377 healthy adults and 920 COPD patients aged 30–65 years, is annually interviewed (ATS-NHLI health questionnaire) and performs pulmonary function test (PFT), which includes: FVC, FEVI, FEVl/FVC, PEF, FEF50 and FEF75. Baseline data analysis showed a more significant excess in respiratory symptmos (8.8% to 21.4%) and lower PFT (2.4% to 8.0%) among patients occupationally exposed to dust, than among healthy exposed panelists (-0.7% to 7.7% excess symptomatology and -0.3 to 5.8% lower PFT). Among patients a significant correlation between PFT and degree of occupational dust exposure was found. Significantly lower FEVl/FVC and excess in respiratory symptoms (with relative risks of 2.47–16.38) was present in healty smokers vs. non smokers as compared with COPD patients.Corresponding author.     

Asbestos disease risk communication conducted by the New Jersey department of health

Since October 1985, the New Jersey Department of Health (NJDOH) has required hospitals to report all patients with a discharge diagnosis of asbestosis. As follow-up to a needs assessment survey of these patients, the NJDOH developed an educational packet including an information bulletin titled “Asbestos Disease: Medical and Legal Facts for Employees” and a pre-stamped postcard evaluation survey. The packet was sent to 1,418 patients reported by hospitals; 433 patients returned the evaluation questionnaire. The survey assessed attitudinal responses (were the materials helpful and easy to understand?) and behavioral responses (did the respondent plan on discussing the materials with a doctor or lawyer?) to the information in the packet. Of the postcard respondents, 85% found the materials helpful, and approximately half indicated that they would discuss the materials with a doctor or lawyer. Of the 33% who were proxy respondents, half appeared not to have understood that the materials had relevance to them as family members. Modifications to the protocol for the asbestos disease educational packet were made based on the evaluation data. Limitations of the evaluation survey and the value of process evaluations in risk communication projects are discussed. © 1993 Wiley-Liss, Inc.     

组织工程化肌腱研究进展

对组织工程化肌腱领域中目前研究的主要成果进行综述，着重阐述了肌腱细胞外基质替代物、肌腱细胞生物学性质及肌腱细胞与细胞外基质材料复合研究中的主要问题。认为，研制适于肌腱细胞生长、粘附和发挥功能的细胞外基质材料；建立生长、增殖可调控的肌腱细胞系；在模拟体内力学条件下，进行肌腱细胞三维培养，将是研究具有特定修复功能的组织工程化肌腱的重要问题。     

Different acute effects of single-axis and multi-axis hand-arm vibration

Under laboratory conditions the effects of single-axis and multi-axis hand-arm vibration exposure on several strain parameters were tested in up to 20 male subjects. As parameters of these acute effects, the biodynamic vibration behavior of the hand-arm system, the electrical activity of the most affected muscle groups, the skin temperature, the vibration sensitivity of the fingertips, and the subjective vibration sensation were measured. When comparing simulated three-axis vibration exposure with single-axis vibration exposure, synergistic effects in the form of an increasing reaction could be found. It could be proven that the vector sum of the frequency-weighted acceleration in the three axes represents the acute effects better than does the weighted acceleration in the main axis alone. This summation has to take into account the relatively lower effects of vibration in the x- or y-direction compared with the z-direction. On the basis of the experimental results a new proposal for frequency weighting of the three different axes and an energetic summation procedure are derived. Application of this knowledge in the International Standard ISO 5349 is proposed.     

Substantiating hazardous exposure to asbestos by examination of pulmonary dust

Summary Substantiation of relevant asbestos risks by microscopic examination sets a lower detection limit at fibres longer than 5 to 10 m and thicker than 0.5 m Such microscopically detectable fibres are, of course, in respect to total quantity the insignificant part of the overall dust burden, but apparently a necessary part of the whole fraction when assessing the relevance of exposure. Until now, no epidemiologically conclusive asbestos risks resulting from occupational exposure have been made known solely with fibre fraction below the microscopic detection limit. Demands for supplementary electromicroscopic examination on the basis of case reports of lung parenchyma damage by fibres of a lower calibre than the microscopic detection limit are, therefore, presently without foundation. The subject examinations reveal that substantiation of asbestos risks with light-optical means, using different methods, provides comparable results. Initially, of course, it is surprising to obtain fluctuations in results of 100000 to 600000 asbestos particles for the same case. However, one must realize that calculations based on intermediate results are responsible for this range of fluctuation, due to the varying degree of asbestos fibre dispersion in the different sections of the lung and, depending on the method of detection used. Interest on the part of everyday occupational medicine and expert opinion is determined by the need to categorize individual cases into different basic classes of risk by referring to relevant morphological facts, such as substantiation of asbestosis or drawing a borderline between persons with occupational risk and those with a non-occupational risk. The subject examinations reveal, using different methods of analysis, equally significant results, which correspond with those published by other authors who used a method which, in terms of expenditure for material and manpower, is also suitable for routine analysis.     

生活环境因素暴露对支气管哮喘非急性发作期患者呼出气一氧化氮水平的影响

背景 呼出气一氧化氮(FeNO)的测量具有安全、无创、简便、重复性好等特点已经被广泛应用于哮喘患者气道炎症的评估,但FeNO的测定结果受到多种因素的影响,生活环境因素暴露可能与FeNO水平有较为密切的关系,而目前关于生活环境因素暴露对FeNO水平影响的研究较少。目的 分析生活环境因素暴露对支气管哮喘非急性发作期患者FeNO水平的影响,以提高临床医生利用FeNO管理哮喘的效能。方法 纳入2018年7月至2020年6月就诊于广州医科大学附属第二医院呼吸内科门诊的109例支气管哮喘非急性发作期患者作为研究对象,通过问卷调查的方法收集资料,问卷信息主要包括一般资料(性别、年龄、身高、体质量)、生活环境因素(包括吸烟史,家人在家是否吸烟,过敏史,居住地位置,居住地离车流量大的主干道位置,居住地周围有无工厂,居住房屋楼层,房屋居住年限,床单、被/枕套清洗晾晒的频率,家中窗帘材料,家中有无盆栽花草,家中垃圾桶有无定期清洗,家中有无饲养宠物,家中有无蟑螂,厨房垃圾有无当天处置,家中是否有毛绒玩具),并收集FeNO的检查资料。根据FeNO水平将支气管哮喘患者分成3组:FeNO低水平组(FeNO<2...     

Potentiation of allergic bronchoconstriction by repeated exposure to formaldehyde in guinea-pigs in vivo

BACKGROUND: Indoor formaldehyde (FA) might worsen allergies and be an underlying factor for the increasing incidence and severity of asthma; the exact mechanism, however, remains unclear. OBJECTIVE: The present study examined the effects of repeated exposure to FA on methacholine- and antigen-induced bronchoconstriction in guinea-pigs in vivo. METHODS: First, non-sensitized guinea-pigs were transnasally treated with 0.1 or 1.0% FA or saline three times a week for 6 weeks, and increasing concentrations of methacholine (50, 100, and 200 microg/mL) were inhaled at 5-min intervals. Second, guinea-pigs pre-treated with transnasal administration of FA or saline using the same protocol were passively sensitized with anti-ovalbumin (OA) serum 7 days before antigen challenge. Third, guinea-pigs were actively sensitized with OA and pre-treated with transnasal administration of FA or saline using the same protocol. The lateral pressure of the tracheal tube (Pao) was measured under anesthesia and artificial ventilation. RESULTS: The antigen-induced increase in Pao in actively sensitized guinea-pigs was significantly potentiated by FA exposure in a dose-dependent manner. The dose-response curve of the methacholine-induced increase in Pao in non-sensitized guinea-pigs or of the antigen-induced increase in Pao in passively sensitized guinea-pigs was not altered by FA exposure. Transnasal administration of FA significantly increased the serum anti-OA homocytotropic antibody titre (IgG) as measured by the passive cutaneous anaphylaxis reaction in actively sensitized guinea-pigs. CONCLUSION: The results suggest that repeated exposure to FA worsens allergic bronchoconstriction through enhancing antigen sensitization.     

Genotypic influences on lead-induced hyperactivity in mice

Male mice, genetically selected for differences in brain weight or from a heterogeneous (HET) stock, were used to explore potential interactions between genotype and exposure to lead as manifested in activity. At the time of birth dams and their pups were given either water or a 0.5% lead acetate solution as the sole source of fluid. Fluid conditions remained constant throughout the experiment. The effects of chronic lead on activity in young adult mice depended on the genotype of the individual. Specifically, in an open field, HET mice exposed to lead tended to be more active than their control counterparts. Low-and high-brain weight lead-exposed mice at times were hypoactive but this effect depended on the specific nature of the measure.This research was supported in part by National Science Foundation Grant DAR7911233 to Peter J. Donovick and Richard G. Bruggight and by Biomedical Research Support Group Grant 5S077RR07149 to Peter J. Donovick.     

Local injection of a mixture of beta-aminopropionitril fumarate and sodium hyaluronate together with controlled exercise for treatment of subacute superficial digital flexor tendonitis in horses

Local injection of a mixture of beta-aminopropionitril fumarate (BAPN-f) and sodium hyaluronate (NaH⁺) together with controlled exercise were evaluated for treatment of superficial digital flexor tendon (SDFT) injuries in horses. Fourteen mixed breed horses with subacute SDF tendon injuries in forelimbs were randomly assigned to two groups. One group received BAPN-f (0.7 mg/ml) and the other received NaH⁺ (10 mg/ml) all by intratendinous injection. Controlled exercise started during the first week after intratendinous treatment and continued for 12 weeks. Cross-sectional area (CSA) of the SDFT, diameter of the SDFT, and relative area of the lesion (presence of CSA) were measured by ultrasonographic examination. Lesions were semiquantitatively graded for echogenicity on a scale of 0 to 4. The lesion severity in CSA was significantly reduced by BAPN and NaH compared to those horses treated by BAPN only (p < 0.05). Lesion echogenicity score was significantly higher in horses treated with BAPN and NaH⁺ at day 0 compared to horses treated with BAPN (p < 0.05). At the end of the study, lesion echogenicity score was significantly reduced in the horses treated with BAPN and NaH⁺ compared to horses treated by BAPN only (p < 0.05). According to the results of the present study, a combination of BAPN-f and NaH⁺ has a greater beneficial effect on tendon healing and remodeling in horses, as assessed by sonographic examination, compared to treatment with single drugs.