β-胡萝卜素立体异构体对环磷酰胺处理小鼠免疫功能的比较研究

就β-胡萝卜素立体异构体对环磷酰胺处理小鼠的免疫功能影响进行了比较研究。结果显示β-胡萝卜素立体异构体对外磷酰胺造成的免疫功能低下具有不同程度的改善作用，提高胸腺和脾脏指数，增强脾脏细胞对刀豆素A（ConA）的反应性和NK活性，血清溶菌酶含量也有所增加。综合各项指标，9-顺式和全反式混合物的作用最明显，提示一定浓度的9-顺式对于提高β-胡萝卜素对机体的总体作用是有一定意义的。     

壳聚糖—明胶混合膜的制备及其生物降解性研究

将壳聚糖与明胶按一定比例混合制膜，通过体外降解及动物体内实验研究了其降解性和生物相容性，结果表明壳聚糖－明胶混合膜在小鼠体现人降解速度较快，并具有较好的生物相容性，溶菌酶对混合膜的生物降解有促进作用。     

Kidney function in stainless steel welders

Summary Seventeen male manual metal-arc stainless steel welders (mean exposure time 20 years) had far higher levels of chromium in urine than individually matched controls (medians 23 vs 1.5 mol/mol creatinine;10.5 vs 0.7 g/g creatinine). However, there were no signs of kidney damage in tests of function of tubuli (-hexosaminidase, lysozyme, and ₂-microglobuline) or glomeruli (albumine clearance).     

琼脂糖火箭电泳法测定唾液溶菌酶活性

本文采用琼脂糖火箭电泳法测定唾液溶菌酶活性,将琼脂扩散方法和电泳技术结合一起,使溶菌酶在电场中泳动,在通过含有作用底物的凝胶时与溶壁微球菌发生水解作用,形成可见的溶菌透明峰,根据峰值与溶菌酶浓度的时数值成正比的关系求得样品溶菌酶含量。该方法简便、快速、稳定性好,灵敏度高,结果准确可靠。在本实验条件下最低检出量为1.25 μg/ml,在5.O-100.0μg/ml范围内呈良好的浓度-峰高的线性关系,r=O.9947,P<0.001,批内重复变异系数CV=4.15％,批间重复变异系数CV=7.42％,平均回收率为95％～114％。     

Crystalloid inclusions in brain macrophages and hemopoietic tissue in GFAP-IL3 mice resemble inclusions identified in multiple sclerosis

Crystalloid inclusions or "pole bodies" observed in brain macrophages in human demyelinating disease represent a morphological enigma. Similar inclusions were detected in brain macrophages from the GFAP-IL3 mouse, a transgenic murine model for macrophage mediated demyelination. Mice also showed inclusions in hematopoietic tissue. They appear to be related to phagocytosis and secretion, respectively, as evidenced by the fact that in phagocytosing cells they often merged with lysozomes and that affected cells showed empty channels open to the interstitium. Based on ultrastructural and immunolocalization studies using chaperonin-10, lysozyme, and cathepsin the authors suggest that these inclusions are consistent with phagocytosis-related secretory products. This study may provide insight into the nature and significance of similar macrophage inclusions recently identified in multiple sclerosis.     

True histiocytic lymphoma of the esophagus in an HIV-positive patient: an ultrastructural study

A 56-year-old white woman, seropositive for human immunodeficiency virus for 18 months without signs of acquired immunodeficiency syndrome, presented with retrosternal pain and progressive dysphagia secondary to an exophytic esophageal mass. Biopsies of the tumor showed a malignant neoplasm composed of pleomorphic, noncohesive cells growing in a diffuse, sheet-like fashion. Immunohistochemically, tumor cells were nonreactive with epithelial, lymphoid, neural, and monocyte/macrophage markers. Despite the noncontributory immunohistochemical findings, ultrastructural study of the tumor cells revealed convincing histiocytic features. Individual cells possessed long, slender filopodial projections, prominent Golgi apparatus, residual bodies, rare lysosomes, and prelysosomes. Immunoglobulin heavy chain and T-cell receptor gamma gene rearrangement studies detected no evidence of a clonal gene rearrangement. The patient responded poorly to chemotherapy and died 5 months after her initial symptom of dysphagia.     

Inflammation markers in nasal lavage, and nasal symptoms in relation to relocation to a newly painted building: a longitudinal study

Introduction: There is a need to evaluate possible health effects of ventilation improvements and emissions from new buildings, in longitudinal studies. New methods to study biological effects on the eyes and upper airways are now available. Material and methods: A longitudinal study was performed on 83 trained social workers in two offices in Uppsala, Sweden. The exposed group (n= 57) moved to a newly redecorated building nearby. Low emitting building material had been used, including a new type of solvent-free water-based paint. The control group (n= 26) worked in the same office during the study period (November 1995 to February 1996). Hygiene management was carried out in both offices, at the beginning and the end of the investigation. Tear film stability (BUT) was measured. Nasal patency was measured by acoustic rhinometry, and eosinophilic cationic protein (ECP), myeloperoxidase (MPO), lysozyme and albumin were analyzed in nasal lavage fluid (NAL). Results: The relocation resulted in an increase in the personal outdoor airflow rate from 11 to 22 l/s. Indoor concentrations of terpenes were higher in the new building, and powdering of the new linoleum floor was observed. Measurements showed low levels of volatile organic compounds (VOC), formaldehyde, carbon dioxide (CO₂), nitrogen dioxide, respirable dust, and microorganisms in the air of all buildings. The move resulted in an increased nasal patency and an increase of ECP and lysozyme in NAL, after adjusting for changes in the control group. No changes were observed for nasal or ocular symptoms. A seasonal effect, with a decrease of ECP, was observed in the control group. Conclusion: A well-ventilated office building can be redecorated without any major ocular or nasal effects, or measurable increase of indoor air pollution if low-emitting building materials are selected. In agreement with previous evidence, the improved ventilation flow may explain the increase of nasal patency. The increase of ECP and lysozyme in NAL suggested an inflammatory effect in the new building. Since this building had increased ventilation flow, increased concentrations of terpenes, and powdering from the polish on the new linoleum floor, identification of causative agents was difficult. The hygiene measures did not give any evidence that emissions from the new type of solvent-free water-based paints or building dampness were responsible for the observed nasal effects. Considering the higher emissions of VOC reported from older types of water-based latex paints and solvent-based wall paints, the new type of solvent-free water-based paint seems to be a good choice from the hygiene point of view. Received: 21 December 1998 / Accepted: 20 June 1999     

Safety evaluation of a novel muramidase for feed application

Safety evaluation of a muramidase produced by a Trichoderma reesei strain (safe lineage), expressing a muramidase gene isolated from Acremonium alcalophilum is presented. Intended use in feed of this enzyme is as digestive aid in broiler chickens.Muramidase 007, was non-mutagenic and non-clastogenic in vitro, and no adverse effects were observed in 90-day subchronic toxicity studies in rats at doses up to 1132 mg TOS/kg body weight/day. The enzyme did not exhibit, in vitro, skin, nor eye irritation potential. Acute aquatic toxicity evaluated on daphnia and algae showed absence of effect of the enzyme at the standard doses tested.Muramidase 007 was fully tolerated by broiler chickens in a 6-weeks tolerance study showing no adverse effects in any of the dietary treatments (0, 1×, 5× and 10× maximum recommended dose).In conclusion, Muramidase 007 is found to be toxicologically inert, and there are no worker's safety concerns if standard precautions are instituted and a non-dusty formulation is employed. Muramidase 007 is well tolerated by the target species (broiler chickens) and cause no harm to the environment. The beneficial safety evaluation of Muramidase 007 is in line with this type of enzyme that is found ubiquitously in nature.     

急性肝衰竭大鼠模型肠道防御素-5、分泌型磷脂酶A2和溶菌酶表达变化及其与细菌移位的关系

目的 探讨急性肝衰竭(ALF)大鼠模型肠道防御素-5(RD-5)、分泌型磷脂酶A2(sPLA2)和溶菌酶(Lysozyme)表达变化及与细菌移位的关系. 方法 将48只健康雄性SD大鼠分为对照组8只和急性肝衰竭模型组40只,模型组再按造模后不同时间点分为5个亚组:8、16、24、48、72 h组.模型组腹腔注射D-氨基半乳糖诱导ALF.取各组肝、脾和肠系膜淋巴结组织匀浆进行细菌培养;肝组织和末段回肠组织经HE染色后光镜下观察病理变化;检测各组末段回肠RD-5、sPLA2、Lysozyme mRNA及sPLA2和Lysozyme的蛋白表达.组间均数比较采用单因素方差分析. 结果 用D-氨基半乳糖成功诱导ALF模型.正常对照组未出现脏器细菌培养阳性,模型组24、48、72 h脏器细菌移位率分别为8.3％、37.5％和58.3％,但72 h小鼠模型的末端回肠结构尚完整,未见黏膜上皮细胞明显脱落坏死情况.模型组大鼠回肠黏膜潘氏细胞RD-5、sPLA2 mRNA相对表达量在早期逐渐升高,16h上升至高峰分别为1.291 ±0.153、1.131±0.128,与对照组的0.725±0.116、0.722±0.112比较,t值分别为69.25、95.71,P值均＜0.01,差异有统计学意义;RD-5、sPLA2mRNA相对表达量随时间延长逐渐下降,在72 h分别为0.415±0.104、0.425±0.076,明显低于对照组,t值分别为31.55、44.98,P值均＜0.01,差异有统计学意义.对照组Lysozyme mRNA相对表达量为0.853±0.093,模型组早期亦升高,8h上升至高峰为1.211±0.107,随后逐渐下降,72h为0.704±0.103,明显低于对照组,差异有统计学意义(t=9.224,P＜0.01).Western blot检测对照组sPLA2和Lysozyme的蛋白相对表达量,分别为0.583±0.121和0.650±0.093,高于模型组72 h的0.327±0.086和0.382±0.057,t值分别为12.28、15.83,P值均＜0.01.免疫组织化学染色结果与Western blot检查结果相一致. 结论 ALF大鼠模型的回肠黏膜免疫屏障功能下降,随着潘氏细胞RD-5、sPLA2和Lysozyme mRNA及蛋白表达下降,脏器细菌移位率增加,且不伴有明显肠黏膜损伤的发生.     

Kidney Scintigraphy after ACE Inhibition in the Diagnosis of Renovascular Hypertension

Suppression of the renin-angiotensin system (RAS) by angiotensin converting enzyme (ACE) inhibition may induce renal failure in patients with bilateral renal artery stenosis. Recent scintigraphic studies with the glomerular tracer technetium-99m-diethylenetriaminepenta-acetate (^99m-Tc DTPA) indicate that in patients with unilateral renal artery stenosis, glomerular filtration rate (GFR) may be markedly reduced in the affected kidney after inhibition of ACE. This finding reflects the important role of the RAS in maintaining GFR (by increasing postglomerular resistance) in states of low renal perfusion pressure. Preliminary observations suggest that this scintigraphic test might be useful in the detection of renovascular hypertension.