豚鼠早期实验性近视眼视网膜色素上皮细胞bFGF表达变化的研究

目的：研究豚鼠早期实验性近视眼视网膜色素上皮(retinal pigment epithelial,RPE)细胞前部及后极部碱性成纤维细胞生长因子(basic fibroblast growth factor,bFGF)的改变,探索近视的发病机制。

方法：两周龄豚鼠30只随机分为A组、B组、C组,每组10只,再随机选取5只10眼正常两周龄豚鼠不作任何干预,作为正常对照眼。选取任意眼戴一-10.00D凹透镜,分别饲养6、15、30d后除去镜片,验光及测眼轴长度确定近视形成后,采用细胞酶消化法培养豚鼠的前部及后极部RPE细胞,取3～6代RPE细胞进行免疫细胞化学、实时荧光定量PCR、Western-blot蛋白印迹法检查前部及后极部RPE细胞中bFGF表达变化。

结果：bFGF的表达定位于细胞浆和细胞核。免疫细胞化学、实时荧光定量PCR、Western-blot蛋白印迹法结果均表明：A、B、C三组实验眼和对照眼前部及后极部RPE细胞均有bFGF的表达,实验组前部及后极部与对照组相应前部及后极部比较,实验组中bFGF的阳性率低于对照组,差异有统计学意义(P<0.05); 而且,随着诱导时间的推移,实验组的阳性率逐渐降低,差异有统计学意义(P<0.05),对照组的阳性率不变,差异无统计学意义(P>0.05); 但实验组和对照组各组自身前部及后极部比较,差异无统计学意义(P>0.05)。

结论：实验组前部及后极部与对照组相应前部及后极部比较,bFGF的表达显著低于对照组。     

骨髓间充质干细胞移植对豚鼠皮肤深Ⅱ度烧伤的治疗作用

目的探讨骨髓间充质干细胞 (MSCs)治疗皮肤深Ⅱ度烧伤的机制。方法体外培养扩增的MSCs悬液 ,以 2× 10 6/ml(A组 )和 2× 10 7/ml(B组 )两种细胞密度移植给皮肤深Ⅱ度烧的受体鼠创面 ,观察创面愈合速度 ,用免疫组织化学检测因子Ⅷ的表达。细胞移植后的第 15、3 0、5 0天 ,通过PCR方法检测创面皮肤组织中移植供体鼠的Y染色体基因表达。结果A、B组治疗侧的创面愈合速度均快于对照侧 ,A、B组治疗侧间无显著性差异。因子Ⅷ检测示第 15、3 0天时 ,A、B两组的微血管密度均多于对照侧 ,A、B组治疗侧间无显著性差异。PCR检测结果表明 ,第 15、3 0、5 0天时在部分受体鼠恢复的创面上有供体鼠Y染色体基因表达。结论骨髓MSCs对皮肤深Ⅱ度烧伤具有明显的疗效。     

Aseptic knee effusion associated with calcified guinea worms

Reported is a case of aseptic knee effusion associated with the presence of a calcified guinea worm, Dracunculus medinensis, in close proximity to the joint. The patient, a native of Nigeria, presented with chronic right knee pain and swelling. He did well with symptomatic treatment including non-steroidal antiinflammatory drugs, rest, ice, and elevation of the leg. Dracunculiasis is prevalent in parts of Asia and Africa, but has been described only rarely in the United States.     

形觉剥夺性高度近视豚鼠巩膜形态改变及缺氧诱导因子-1α和氧自由基在高度近视中的作用

目的　观察形觉剥夺性高度近视（form deprivation high myopia，FDHM）豚鼠巩膜形态变化，探讨缺氧诱导因子-1α（hypoxia-inducible factor-1α，HIF-1α）及氧自由基在高度近视中的作用。方法　将豚鼠适应性饲养1周后，随机分为空白对照组（25只）和模型组（25只）。模型组豚鼠右眼行眼睑缝合，所有模型组豚鼠均选择右眼作为FDHM组，对侧眼为自身对照组。空白对照组豚鼠不做任何处理。于造模前及造模后8周采用检影镜测量屈光度，A超进行生物测量。形觉剥夺8周以后处死豚鼠，观察巩膜形态和超微结构的变化，测定巩膜HIF-1α相对表达量，超氧化物歧化酶（superoxide dismutase，SOD）活力及丙二醛（malondialdehyde，MDA）的含量。结果　豚鼠形觉剥夺8周以后，FDHM组屈光度从（+3.59±0.33）D变为（-7.96±0.55）D，明显高于空白对照组（+0.89±0.32）D、自身对照组（-0.55±0.49）D（均为P<0.05）；玻璃体腔深度为（4.12±0.13）mm明显高于空白对照组（3.71±0.23）mm和自身对照组（3.93±0.04）mm（均为P<0.05）；眼轴长度为（8.93±0.22）mm明显长于空白对照组（7.95±0.37）mm和自身对照组（8.01±0.15）mm（均为P<0.05）。巩膜组织明显变薄，细胞外基质增多，成纤维细胞密度降低，胶原纤维平均直径减小。FDHM组巩膜中HIF-1α相对表达量、MDA含量明显高于空白对照组和自身对照组，SOD活力明显低于空白对照组和自身对照组（均为P<0.05）。结论　形觉剥夺8周后，豚鼠FDHM眼近视度数明显增加，玻璃体腔深度增加，眼轴延长，巩膜形态发生病理性变化；HIF-1α、SOD、MDA可能参与了FDHM的形成。     

Study on testicular response to prolong artemisinin‐based combination therapy treatments in guinea pigs

Artemisinin‐based combination therapies (ACTs) are first‐line agents in malaria chemotherapy, but often abused in malaria endemic countries including Nigeria. This study investigated the effects of prolong treatment of artesunate–amodiaquine (ATS–Amod), artesunate‐sulfadoxine‐pyrimethamine (ATS–SP) and artemether–lumefantrine (ATM–Lum) on testicular indices in guinea pigs. Sixty‐five pigs were grouped into 13 (n = 5 per group). Six groups were given standard or double therapeutic dose equivalents of ATS–Amod, ATS‐SP or ATM–Lum daily for 14 day and sacrificed 24 hr after treatments. Six other groups (recovery groups) received similar drug treatments but allowed to recover for 14 day before sacrificed. Control group received distilled water. ATS–Amod, ATS–SP and ATM–Lum, respectively, decreased (p < .01) sperm count (17.7%, 37.7% and 33.8%), motility (48.6%, 50% and 51.4%), viability (32.7%, 43.7% and 35.9%) and morphology (123.5%, 0% and 0%), compared to control. These effects were reversed in recovery animals. Also, they decreased (p < .01) luteinising hormone and testosterone serum levels, without affecting follicle‐stimulating hormone. Testicular malondialdehyde level was elevated, and glutathione was decreased, while catalase and superoxide dismutase enzymes were unaffected by the drugs. The alterations were all reversed in recovery animals. The study reveals that prolong administration of ACTs results in reversible alteration of sperm parameters and reduction of testosterone which is partly attributable to oxidative stress.     

Herbal polysaccharides and cough reflex

In the last decades plant substances have become a leading form of treatment of many respiratory symptoms, including cough. It has been shown that compounds purified form polysaccharides from Adhatoda vasica, Withania somnifera, and Glycyrrhiza glabra have various biological activities, such as antioxidant, anti-inflammatory, immunomodulating, antispasmodic action, or antiallergic properties, and they often act as cough suppressants. This work demonstrates new natural substitutes for synthetic antitussives whose application is associated with numerous adverse effects. We investigated pharmacodynamic characteristics of arabinogalacatan samples extracted from A. vasica, W. somnifera, and G. glabra. These extracts showed the ability to reduce citric acid-induced cough in awake guinea pigs after oral administration in a dose of 50 mg/kg. The strongest antitussive effect (81%) was found after application of the extract from G. glabra. There was a 67% cough suppression with A. vasica and 61% with W. somnifera, which was comparable with the antitussive activity of codeine (62%).     

Development of a novel,guinea pig-specific IFN-γ ELISPOT assay and characterization of guinea pig cytomegalovirus GP83-specific cellular immune responses following immunization with a modified vaccinia virus Ankara (MVA)-vectored GP83 vaccine

The guinea pig (Cavia porcellus) provides a useful animal model for studying the pathogenesis of many infectious diseases, and for preclinical evaluation of vaccines. However, guinea pig models are limited by the lack of immunological reagents required for characterization and quantification of antigen-specific T cell responses. To address this deficiency, an enzyme-linked immunospot (ELISPOT) assay for guinea pig interferon (IFN)-γ was developed to measure antigen/epitope-specific T cell responses to guinea pig cytomegalovirus (GPCMV) vaccines. Using splenocytes harvested from animals vaccinated with a modified vaccinia virus Ankara (MVA) vector encoding the GPCMV GP83 (homolog of human CMV pp65 [gpUL83]) protein, we were able to enumerate and map antigen-specific responses, both in vaccinated as well as GPCMV-infected animals, using a panel of GP83-specific peptides. Several potential immunodominant GP83-specific peptides were identified, including one epitope, LGIVHFFDN, that was noted in all guinea pigs that had a detectable CD8+ response to GP83. Development of a guinea pig IFN-γ ELISPOT should be useful in characterization of additional T cell-specific responses to GPCMV, as well as other pathogens. This information in turn can help focus future experimental evaluation of immunization strategies, both for GPCMV as well as for other vaccine-preventable illnesses studied in the guinea pig model.     

Skin permeation and metabolism of di(2-ethylhexyl) phthalate (DEHP)

Phthalates are suspected to be endocrine disruptors. Di(2-ethylhexyl) phthalate (DEHP) is assumed to have low dermal absorption; however, previous in vitro skin permeation studies have shown large permeation differences. Our aims were to determine DEHP permeation parameters and assess extent of skin DEHP metabolism among workers highly exposed to these lipophilic, low volatile substances.     

Development of a guinea pig cutaneous radiation injury model using low penetrating X-rays

Purpose: A guinea pig skin model was developed to determine the dose-dependent response to soft X-ray radiation into the dermis.

Materials and methods: X-ray exposure (50 kVp) was defined to a 4.0?×?4.0?cm area on the lateral surface of a guinea pig using lead shielding. Guinea pigs were exposed to a single fraction of X-ray irradiation ranging from 25–79?Gy via an XRAD320ix Biological Irradiator with the collimator removed. Gross skin changes were measured using clinical assessments defined by the Kumar scale. Skin contracture was assessed, as well as histological evaluations.

Results: Loss of dermal integrity was shown after a single dose of soft X-ray radiation at or above 32?Gy with the central 2.0?×?2.0?cm of the exposed site being the most affected. Hallmarks of the skin injury included moist desquamation, ulceration and wound contracture, as well as alterations in epithelium, dermis, muscle and adipose. Changes in the skin were time- and radiation dose-dependent. Full-thickness injury occurred without animal mortality or gross changes in the underlying organs.

Conclusions: The guinea pig is an appropriate small animal model for the short-term screening of countermeasures for cutaneous radiation injury (CRI).