Heparin–coated circuit during cardiopulmonary bypass

A prospective randomized study was performed to investigate the effect of surface coating with covalently endpoint–attached heparin (Carmeda Bio Active Surface) and reduced general heparinization on haematological indices and complement C5 activation. Care was taken to optimize the rheological design of the system using centrifugal pump and a closed system without venting or machine suction. Twenty patients scheduled for aortocoronary bypass grafting (EF > 0.5) participated in the study. Ten patients were randomized to be treated with heparin–coated equipment (CBAS) and reduced i.v. heparin (1.5 mg kg^-1) while 10 patients treated with identical but noncoated equipment and full heparinization (3 mg–kg^-1) served in a Control group. A vacuum suction was used to collect the blood from the operating field and it was autotransfused at weaning from extracorporeal circulation (ECC). Blood samples were obtained from the venous (precircuit) and arterial (postcircuit) side. We used a new and very specific method for detection of C5a based on monoclonal antibodies. The concentration of C5a was low in both groups during the operation but a significant increase was seen on days 1 and 2. In the Control group there was an increase from 10.2 ngml^-1±1.2 to 27.5 ng ml^-1 ± 4.8 on day 2 and in the CBAS group from 10.7 ng ml^-1 ± 1.2 to 35.6 ng ml^-1 ± 11.6 on day 2 (NS between groups). The granulocytes and total leukocyte count increased at the end of ECC and was maintained at the elevated level throughout the study period. The amount of free haemoglobin was high in the autotransfused blood in both groups. The present results confirm the feasibility of reducing general heparin when using heparin–coated systems but the study does not support the superiority of such coating with regard to biocompatibility in short procedures with a Theologically optimized circuit. The potential benefit from reduced heparin and protamine has not been fully evaluated.     

Current prevalence of hepatitis A,B and C in a well-defined area in rural Crete,Greece

A seroepidemiological study was carried out in a geographically well-defined area in rural Crete in order to determine the prevalence of A, B and C hepatitis markers in the local population. Serum samples were obtained from 257 subjects (94 males, 163 females), aged 15 years and over, who visited the primary health care services of the Spili Health Centre between July 1993 and March 1994, and from 164 subjects (83 males, 81 females) randomly selected from households in three neighbouring villages of the study area. In samples obtained from the Spili Health Centre, antibodies to hepatitis A virus (anti-HAV) were detected in 234/244 (95.9%) subjects, antibodies to hepatitis B virus core antigen (HBcAb) were detected in 63/257 (24.5%) subjects and antibodies to hepatitis C virus (anti-HCV) were detected in 28/257 (10.9%) subjects. The corresponding figures for those randomly selected from the villages were 135/154 (87.7%), 16/164 (9.8%) and 5/164 (3%) respectively. Hepatitis B surface antigen (HBsAg) was positive in three (1.2%) subjects from the first group, while none of those recruited from the villages were positive for HBsAg. Interestingly, hepatitis markers were closely associated with age. No subjects under the age of 15 years showed evidence of prior hepatitis A infection and approximately 20% of those between 15 and 44 years of age were also negative. By contrast, practically all subjects older than 44 years were anti-HAV positive. Similarly, the majority of all those who were anti-HCV positive were older subjects. Seroepidemiology of hepatitis in this well-defined population seems to be different from other parts of Greece, at least for hepatitis B and C viruses. There is a very low prevalence of HBsAg and a very high incidence of anti-HCV. Low exposure to HAV, as found in other parts of the country, was also found in the younger generation in this rural area of Crete.     

C3 Deposition in IgA Nephropathy in Children and Adolescents

The aim of this study was to assess the significance of C3 deposition in IgA nephropathy in children and adolescents. One hundred and two patients aged 5–21 years (57 male and 45 female) were studied. The findings of C3 deposition were classified into 8 groups by immunofluorescent (IF) pattern and intensity as follows: group MC3+ (N = 12): mesangiocapillary pattern and 3+ in intensity; group MC2+ (N = 13): mesangiocapillary and 2+; group MC1 + (N = 4): mesangiocapillary and 1 +; group M3+ (N = 11): mesangial and 3+; group M2+ (N = 24): mesangial and 2+; group M1 + (N=18): mesangial 1 +; group S (N = 12): only segmentally positive; and group N (N = 8): negative. Histological changes were scored semiquantitatively as an activity index (cellular proliferation, necrosis, interstitial cell infiltration, and cellular crescents) and a chronicity index (mesangial sclerosis, segmental and global glomerular sclerosis, fibrous crescents, adhesion and tubulo-interstitial change). IF findings were scored semiquantitatively and laboratory findings were also studied. The following results were obtained: 1) The scores of total activity index in MC groups were higher than in the M, S or N groups, and the greater the degree of C3 deposition, the higher the score; 2) Such result was not evident in the chronicity index; 3) High IF scores of IgG and IgM were found in the MC3+ and MC2+ groups; 4) Hematuria was more severe in MC3+ and MC2+ than in other groups, and proteinuria was more prominent in the MC than other groups. Thus the degree of C3 deposition was parallel with histological activity and urinary findings.     

Vaccination against gastrointestinal nematodes of sheep using purified secretory acetylcholinesterase from Trichostrongylus colubriformis– an initial pilot study

Purified secretory acetylcholinesterase (sAChE) from Trichostrongylus colubriformis was used as a candidate vaccine against mixed T. colubriformis, Haemonchus contortus and C. oncophora challenge infections of sheep. Cross species protection was achieved with an average reduction in worm burden of all species of 31%, rising to 58% in individual cases. There was no consistent reduction in faecal egg counts and increases in anti-T. colubriformis sAChE IgG antibody levels following vaccination were modest. We suggest that improved antigen delivery systems will result in increased host protection.     

Positron emission tomography in oncology

Summary. The particular advantages of positron emission tomography (PET) technique are that it has higher sensitivity, higher resolution, and a higher quality of image than that found in conventional nuclear medicine. The possibility of quantification and the wide range of useful tracers have raised expectations of this new method. To date, most of the human PET cancer studies have been performed with [¹⁸F]fluorodeoxyglucose (FDG) or [¹¹CJmethionine. These are good imaging agents for tumours. However, more specific radiopharmaceuticals are required if other features of tumour metabolism are to be observed, f¹¹Thymidine may prove to be a good tracer for quantitative measurements of tumour proliferation and [¹⁸F]misonidazole has been suggested for imaging of hypoxia.     

超抗原TSST-1之靶TCRVβHV4序列的特征分析

首先对人和小鼠的TCRVβ的氨基酸序列进行多序列对准,就Vβ之HV4片段进行比较,分析与超抗原TSST-1结合的四种Vβ（小鼠Vβ3、Vβ15、Vβ17和人Vβ2）之HV4序列内是否存在特定的氨基酸残基排列主型。结果发现:小鼠Vβ3和Vβ17的HV4具有特异的RFSAXCXSNS主型,而小鼠Vβ15和人β2的HV4则含独特的KFXIXH主型。提示:与TSST-1结合的四种Vβ所对应的T细胞识别表位可能不止一个。     

活血化瘀法治疗髌骨软骨软化症的探讨

本文从髌骨软骨软化症的病因病理出发，阐述了活血化瘀疗法治疗髌骨软骨软化症的作用及其原理，列举了活血化瘀法在该病治疗中的具体运用，同时强调了在辨证施治基础上活血化瘀的重要性。     

精氨酸加压素（AVP）的衍生物AVP4—8不能作用于AVPV1a受体而诱发电流反应

在微量注射大量肝脏ｍＲＮＡ之后，通过电压箝方法进行功能鉴定，两栖类卵母细胞成功地表达了ＡＶＰＶ１ａ受体。但在灌流ＡＶ４－８溶液时，却不能诱导卵母细胞产生内向振荡电流反应。提示ＡＶＰ４－８不能通过ＡＶＰＶ１ａ受体而介导生理学效应。     

Demonstration of synergistic effects of hyperthermia and photodynamic therapy using the chick chorioallantoic membrane model.

The chick chorioallantoic membrane (CAM) model was used to study vascular effects of photodynamic therapy (PDT) and hyperthermia (HPT) and the synergism of these modalities. The CAM is a convenient medium for monitoring the modifications of the vasculature. It is possible to view the CAM and to examine structural changes of individual blood vessels in real time. Moreover, the CAM is a closed system which lends itself to mathematical modeling of the temporal and spatial temperature profile and in which HPT can be performed quantitatively and to a selected depth, using different lasers. A porphyrin-type photosensitizer solution was applied to areas of the CAM, defined by teflon O-rings placed on the surface. Uptake dynamics of the sensitizer into the CAM was determined by analyzing its fluorescence in vivo. The CAM area was irradiated with a dual-wavelength laser system composed of a dye laser at 644 nm (to induce PDT) and a CO2 laser at 10.6 microns (to bring about HPT). Damage to the CAM vasculature, due to combined PDT+HPT, was compared to the outcome of the separate modalities, and a synergistic effect of about 40% was observed.