A comparative study of the proteolytic enzymes of Trypanosoma brucei, T. equiperdum, T. evansi, T. vivax, Leishmania tarentolae and Crithidia fasciculata

Four types of proteolytic activity were detected in the bloodstream form of each of the four Trypanosoma species: (i) HPAase, active on hide powder azure and detected on polyacrylamide gels containing denatured haemoglobin; (ii) AZCase, active on azocasein; (iii) type 1, active on the chromogenic peptide N-benzoyl-L-prolyl-L-phenylalanyl-L-arginine p-nitroanilide in the presence of dithiothreitol, and (iv) type 2, active against several nitroanilide derivatives in the absence of dithiothreitol. Studies of the pH optimum, dithiothreitol requirement and inhibitor sensitivities of the proteolytic activities suggested that: (a) HPAase and type 1 activities could be due to the same enzymes, probably a family of cysteine proteinases; (b) AZCase had some characteristics of a cysteine proteinase, but was not identical to HPAase, and (c) type 2 activity could be due to a serine proteinase. Procyclic T. brucei contained relatively low cysteine proteinase activities (HPAase, AZCase and type 1) but high type 2 activity. Their proteolytic enzymes thus were apparently more similar to those in Crithidia fasciculata and Leishmania tarentolae promastigotes than those in T. brucei bloodstream forms.     

重组小鼠干细胞逆转录病毒载体高效基因转染CD41+、UT7、U937和MDA-MB-435细胞

目的:研究重组小鼠干细胞逆转录病毒载体介导基因转染,探索一条高效基因转染的途径,为重组小鼠干细胞逆转录病毒载体在基因转染中的应用提供理论依据和奠定实验基础。方法:①逆转录病毒载体的构建:EC1-4(repeats1-4ofcadherin-5extracellulardomains)基因克隆产物和mutant(Ser222A)MEK1基因克隆产物,Bg1Ⅱ和EcoRⅠ限制性内切核酸酶切割后,克隆进入逆转录病毒表达载体pMSCV。②CD41⁺细胞的获取和细胞培养:从脐带血分离的CD34⁺细胞通过TPO诱导表达CD41,FACS分离CD41⁺细胞。高糖DMEM培养液培养NIH3T3和MDA-MB-435细胞,U937细胞培养在RPMI-1640培养液,UT7细胞是细胞因子依赖性细胞株,Iscove'smodifiedDulbeco's培养液中加入GM-CSF。③测定病毒滴度:逆转录病毒载体转入包装细胞293,36h后收集病毒上清液,感染NIH3T3细胞,流式细胞仪测定病毒滴度。④Westernblot:基因转染CD41⁺、UT7、U937和MDA-MB-435细胞,Westernblot检测基因产物的表达。结果:293细胞产生高滴度MEK1pMSCV病毒:3.1×10⁷,高滴度EC1-4pMSCV病毒:1.0×10⁸。用稀释8倍的病毒转染基因,重组逆转录病毒MEK1pMSCV转染白血病细胞株UT7和U973,GFP阳性细胞(转染阳性细胞)分别是60.73％、72.56％。重组逆转录病毒MEK1pMSCV转染原代培养细胞CD41⁺,GFP阳性细胞为30.57％。重组逆转录病毒EC1-4pMSCV转染人乳腺癌细胞株MDA-MB-435,GFP阳性细胞为97.54％。TPO作用CD41⁺和UT7细胞以及血清对U973细胞的作用,显示出外源mutationMEK基因的dominantnegative的效应,实验组磷酸化的MEK1减少。EC1-4基因转染的MDA-MB-435细胞表达了EC1-4基因产物。结论:重组小鼠干细胞逆转录病毒载体能高效基因转染CD41⁺、UT7、U937和MDA-MB-435细胞,转染的基因能稳定地表达。     

Immuno-proteomic profiling reveals aberrant immune cell regulation in the airways of individuals with ongoing post-COVID-19 respiratory disease

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桡侧腕屈与腕长伸肌腱部分转位修复手部关节脱位应用解剖

目的 :为桡侧腕屈与腕长伸肌腱部分转位修复桡尺远侧及第 1腕掌关节脱位提供解剖学基础。方法 :3 0侧成人上肢标本 ,分别对桡侧腕屈肌腱、桡侧腕长伸肌腱进行形态学测量。结果 :桡侧腕长伸肌腱性部长 ( 17.8± 2 .6)cm ,肌腱的上、中、下段宽分别为 ( 13 .7± 3 .1)、( 5 .6± 1.1)和 ( 4 .6± 0 .5 7)mm肌腱的上、中、下段厚分别为 ( 1.5± 0 .5 )、( 2 .0± 0 .3 )和 ( 2 .4± 0 .3 )mm。桡侧腕屈肌腱性部长 ( 14 .3± 1.1)cm ,肌腱的上、中、下段宽分别为 ( 9.11.4)、( 5 .5± 0 .9)和 ( 4 .0± 0 .4) ,肌腱的上、中、下段厚分别为 ( 2 .4± 0 .6)、( 2 .2± 0 .4)和 ( 2 .6± 0 .5 )mm。结论 :采用桡侧腕屈肌腱和桡侧腕长伸肌腱部分转位 ,有足够的长度和强度 ,适用于桡尺远侧关节或第 1腕掌关节脱位的修复 ,临床应用获得良好效果     

Apoptosis and apoptosis-associated perturbations of peripheral blood lymphocytes during HIV infection: comparison between AIDS patients and asymptomatic long-term non-progressors

This study was designed to compare the degree of lymphocyte apoptosis and Fas-Fas ligand (FasL) expression in AIDS patients and long-term non-progressors (LTNPs) and correlate these parameters with apoptosis-associated perturbations in lymphocyte function. LTNPs had a lower frequency of apoptotic CD4+ and CD8+ T cells compared with subjects with AIDS. This correlated with a lower frequency of cells expressing Fas and FasL. The frequency of selected lymphocyte populations exhibiting a disrupted mitochondrial transmembrane potential (DeltaPsim) and increased superoxide generation was lower in LTNPs than in patients with AIDS; these abnormalities were associated with lower levels of caspase-1 activation in LTNPs. The results indicate a significantly reduced level of apoptosis and apoptosis-associated parameters in LTNPs than in patients developing AIDS. Based on these findings, a crucial role for mitochondria can be predicted in the process of lymphocyte apoptosis during the evolution of AIDS.     

The obstetric outcome of singleton pregnancies following in-vitro fertilization/gamete intra-Fallopian transfer

The present study compares 465 singleton live deliveries fromin-vitro fertilization/gamete intra-Fallopian transfer (IVF/GIFT)pregnancies with a large control population to evaluate theincidence of pre-term delivery and small for gestational age(SGA) or very small for gestation age (VSGA) babies resultingfrom IVF/GIFT pregnancies. Overall the incidence of SGA or VSGAfrom an IVF/GIFT pregnancy is higher than from the normal obstetricpopulation (SGA odds ratio 1.76, 95% confidence interval (CI):1.38–2.25 and VSGA odds ratio 1.61, 95% CI: 1.05–2.46)particularly among primiparous women (SGA odds ratio 1.99, 95%CI: 1.25–3.16 and VSGA odds ratio 1.97, 95% CI: 1.49–2.62).After stratifying by the cause of infertility, only women withunexplained infertility had a significantly higher proportionof SGA/VSGA babies. There was a significantly higher incidenceof pre-term deliveries among the young primiparae (odds ratio5.02, 95% CI: 3.09–8.13). Thus the excess risk of deliveringa SGA/VSGA baby and pre-term delivery from an IVF/GIFT pregnancyseems to be largely confined to women with unexplained infertilityand young primiparae.     

Gender difference in the relationship of performance in the handgrip and standing long jump tests to lean limb volume in young adults

Summary Groups of young, adult males and females performed the handgrip and standing long jump tests. Their total forearm and leg volumes were calculated from a series of circumference and length measurements, and the lean volumes (bone + muscle) calculated by taking the skinfold thickness into consideration. In the handgrip, the mean female performance was 298 N compared with 496 N for the males. In the standing long jump, mean performance expressed as distance x body mass was 87.3 kg · m for females compared with 137.7 kg · m for males. These superior performances of males could simply reflect their greater muscle mass, as the mean lean volumes of female and male limbs respectively were 0.54 l and 0.89 l for forearms, and 11.82 l and 14.82 l for the two legs. However, when the performances of males and females were grouped by lean limb volume, it was found that while in both tests there were linear relationships, males and females did not share a common line. In both tests the male relationship was at a higher level than the female; therefore, for a given lean volume, the male performance was significantly superior to that of the female. The gender difference found in this study has not been seen in other studies in which the performance of skeletal muscle has been related to the cross-sectional area of the active muscles and the possible reasons for the differences are considered.     

Skeletal dysplasia with short,angulated femora (kyphomelic dysplasia)

We report on an infant with broad and severely angulated short femora as the most salient manifestation of a generalized skeletal dysplasia. Other findings include congenital bowing of other long bones, narrow thorax, platyspondyly, micrognathia, and skin dimples. A marked improvement of the bowing and of the irregular flare of the metaphyses was noted over a period of 6 mo. Congenital bowing of long bones can be an isolated finding or associated with other anomalies, so the purpose of reporting all cases is important for further nosologic and pathogenetic elucidation. Because of the severity of the femoral involvement, the condition has been called kyphomelic dysplasia. It may be an autosomal recessive trait. recessive trait.     

Haemangiosarcoma of bone

Summary Haemangiosarcoma of bone is a very rare primary tumour with a variable history and differing radiographic and histological appearances. In some cases the lesion has similar features to the so-called adamantinoma of long bones in which the histogenesis is also unknown.Such a lesion is described which ocurred in the shaft of the right humerus of a 31-year-old man. Radiographically a centrally located area of osteolysis was seen without marginal sclerosis, but with erosion of the bony cortex. A biopsy was performed 16 months after the first radiographic examination and showed malignant tumour tissue which was difficult to classify histomorphologically. Several different neoplasms such as Ewing's sarcoma, myeloma, liposarcoma, malignant fibrous histiocytoma or a bone metastasis were suggested. Finally, a haemangiosarcoma or so-called adamantinoma of long bones was considered. The tumour was completely removed by en-bloc resection.Careful histomorphological investigation of the tumour tissue by means of light microscopy, cytology and electronmicroscopy showed a vascular pattern characteristic of a haemangiosarcoma. Using cytophotometric DNA measurements of the tumour cells, the lesion could be classified as being of lowgrade malignancy. This is confirmed since there has now been a 4-year follow up with no local recurrence or metastasis.There are many similarities between a well-differentiated haemangiosarcoma and an adamantinoma of long bones. The differential diagnosis and the histogenesis of the latter lesion is discussed. It is emphasized that the so-called adamantinoma of a long bone probably has a vascular origin.

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Résumé L'hémangiosarcome est une tumeur osseuse primaire très rare, dont l'evolution est variable et dont les aspects radiologiques et histologiques sont divers. Dans quelques cas, la lésion ressemble à ce que l'on appelle «adamantinome des os longs», dont l'histogénèse est également inconnue.On présente ici un cas d'une telle tumeur, siégeant au niveau de la diaphyse humérale droite, chez un homme de 31 ans. Radiologiquement, il existait une zone centrale d'ostéolyse sans sclérose marginale mais avec érosion de la corticale. Une biopsie effectuée 16 mois après le premier examen radiologique a montré un tissu tumoral malin, difficile à classer histomorphologiquement.Plusieurs diagnostic ont été envisagée: sarcome d'Ewing, myélome, liposarcome, histiocystome fibreux malin, ou métastase osseuse. Finalement on a retenu le diagnostic soit d'hémangiosarcome, soit d'adamantinome. La tumeur a été complètement enlevée par résection en bloc.Des investigations histomorphologiques poussées du tissu tumoral par microscopie optique, cytologie et microscopie électronique ont mis en évidence les aspects vasculaires caractéristiques d'un hémangiosarcome. En utilisant les mesures cyto-photométriques d'ADN des cellules tumorales, la lésion a pu être classée comme ayant un degré de malignité peu élevé. Ceci a été confirmé par l'évolution, puisqu'avec 4 ans de recul il n'y a ni récidive locale ni métastase.Il y a beaucoup de similitudes entre un hémangiosarcome bien différencié et un adamantinome des os longs. Le diagnostic différentiel et l'histogénèse de cette dernière lésion sont discutes. L'origine vasculaire probable de l'adamentinome est soulignée.