常见肿瘤患者血清维生素A,E,C水平

本文报告２６０例恶性肿瘤患者血清维生素Ａ、Ｅ、Ｃ水平的测定结果。发现除慢性白血病外，蓁７种恶性肿瘤患者血清维生素Ａ水平平均显著低于健康人（Ｐ＜０．０１）；急性白血，肝癌、食管癌患者血清维生素Ｅ水平显著低于健康人（Ｐ＜０．０５）；急性粒细胞白血病、急性单核细胞白血病、肝癌患者血维生素Ｃ水平显著低于健康人（Ｐ＜０．０１）。本研究工作为维生素Ａ、Ｅ、Ｃ药物在肿瘤临床上的应用提供了参考。     

Codon usage patterns in chromosomal and retrotransposon genes of the mosquito Anopheles gambiae

Codon usage was compiled for fourteen chromosomal genes and four retrotransposons from the mosquito Anopheles gambiae. Variation exists among chromosomal genes in the degree of bias. The genes showing the highest bias are probably most highly expressed. In these genes, the base composition at the third codon position is much richer in G + C than is the overall coding sequence. Thus, codon usage is biased toward G- or C-ending codons. Codon usage in each retrotransposon is quite different, not only from chromosomal genes but also from the other retrotransposons. Codon usage comparisons among homologous genes from An. gambiae and two other Dipterans, the yellow fever mosquito Aedes aegypti and the fruitfly Drosophila melanogaster, show that while there are similarities, particularly between An. gambiae and D. melanogaster in the preference for G-and C-ending codons, each species has evolved a distinct pattern of codon usage.     

Amadori糖化白蛋白对牛视网膜血管二酯酰甘油--蛋白激酶C级联的影响

目的 :探讨Amadori糖化血清白蛋白对牛视网膜血管二酯酰甘油 (DAG)———蛋白激酶C(PKC)信号级联的影响及d-α-生育酚的干预作用。方法 :体外制备的Amadori糖化的牛血清白蛋白 (AGSA)分别在生理浓度葡萄糖 (5 .5mmol/L)和高浓度葡萄糖 (2 0mmol/L)培养液中作用于新鲜牛视网膜血管。采用薄层层析和放射自显影法测定DAG含量和PKC活性 ;并检测d -α-生育酚预处理后DAG、PKC改变。结果 :在生理葡萄糖浓度下 ,牛视网膜血管暴露于AGSA2 4h或 72h后细胞内DAG含量、PKC活性均较对照组显著增加 ,当AGSA和高葡萄糖同时作用于牛视网膜血管时 ,DAG -PKC级联显著激活 ,分别为正常葡萄糖组的 3.4 7倍和 4 .5 4倍 ;在正常血清培养液中 ,与 5 .5mmol/L的葡萄糖相比 ,2 0mmol/L高糖在 2 4h时并不刺激DAG含量增加 (P >0 .0 5 ) ,而 72h时则较对照组增加 4 5 % ,PKC活性较对照增加 5 6 % ,而d -α -生育酚可逆转上述生化改变。结论 :Amadori糖化血清白蛋白可在生理葡萄糖浓度下刺激DAG -PKC途径活化 ,从而影响血管一系列生理功能 ,而d -α-生育酚对血管生化改变有保护作用。     

硒和维生素C对白血病细胞增殖及细胞毒性的研究

目的本文主要研究硒和维生素Ｃ影响髓系与非髓系白血病细胞增殖及其细胞毒性的异同。方法体外培养髓系白血病细胞株ＨＬ６０及非髓系细胞株Ｋ５６２，培养时分别设Ｓｅ（５μｍ、８μｍ、１１μｍ）及ＶｉｔＣ（５μｍ、１０μｍ、１００μｍ）实验组及对照组，培养２４ｈ、４８ｈ、７２ｈ后分别取样，利用台盼蓝拒染法进行细胞计数，绘制细胞生长曲线，并通过噻唑蓝比色分析法研究Ｓｅ及ＶｉｔＣ对ＨＬ６０、Ｋ５６２细胞毒性。结果细胞生长曲线显示：Ｓｅ（５～１１μｍ）及ＶｉｔＣ（５～１０μｍ）对ＨＬ６０、Ｋ５６２细胞增殖均有抑制作用。ＭＴＴ结果显示：Ｓｅ（５～１５μｍ）对两种细胞均有细胞毒性。ＶｉｔＣ（５～１０μｍ）对ＨＬ６０具有细胞毒性，而ＶｉｔＣ（５～１００μｍ）对于Ｋ５６２，短时间内毒性作用较明显，随作用时间延长而减弱。结论本实验结果提示：Ｓｅ及ＶｉｔＣ对髓系和非髓系白血病细胞增殖均有抑制作用，但ＶｉｔＣ对于ＨＬ６０和Ｋ５６２作用机制是不同的。这为白血病的化学预防和临床辅助治疗提供一定的理论依据。     

广西百色地区肝病患者及受血者HCV感染现状调查

笔者应用ＥＬＩＳＡ法对广西百色地区１７９例各类肝病患者及４１例受血者血清进行了抗－ＨＣＶ检测。结果各类肝病抗－ＨＣＶ阳性率为１７．９％，受血者抗－ＨＣＶ阳性率为３１．７％。在急性肝炎（急肝）、慢性肝炎（慢肝）、肝硬化和肝癌中，抗－ＨＣＶ阳性率各为４．３％（１／２３）、１２．８％（１０／７８）、２８．６％（１２／４２）和２５．０％（９／３６）。抗－ＨＣＶ阳性率有随肝病慢性比而增高的趋势，肝硬化的抗－ＨＣＶ阳性率明显高于急肝或慢肝（Ｐ＜０．０５），而肝癌的抗－ＨＣＶ阳性率与急肝或慢肝相差不显著（Ｐ＞０．０５或０．１），且发现ＨＢｓＡｇ阴性肝病者的抗－ＨＣＶ阳性率明显高于ＨＢｓＡｇ阳性患者（Ｐ＜０．５），肝病患者抗－ＨＣＶ的检出率与ＡＬＴ活性无关（Ｐ＞０．０５）。在受血者中，抗－ＨＣＶ的检出率与受血次数、ＡＬＴ活性关系非常密切。因此，加强对ＨＣＶ的检测是当前预防输血后肝炎的紧迫任务。     

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.