The hepatitis B immunization programme in Singapore

A voluntary immunization programme to prevent perinatal transmission of hepatitis B virus (HBV) infection in Singapore was implemented on 1 October 1985 as an integral component of the national childhood immunization programme. Up to April 1988, a total of 68,845 mothers who attended government maternal and child health clinics were screened for the disease. Of these, 2432 (3.5%) were positive for hepatitis B surface antigen (HBsAg) and 904 (1.3%) for hepatitis B e antigen (HBeAg). Virtually all the babies born to carrier mothers completed the full immunization schedule; and in addition, those of HBeAg-positive mothers were given a dose of hepatitis B immunoglobulin at birth. The hepatitis B immunization programme was extended on 1 September 1987 to cover all newborns. About 90% of the 15,943 babies delivered in government institutions from September 1987 to April 1988 were immunized at birth, with the subsequent doses being administered at maternal and child health clinics at 4-6 weeks and 5 months later. More than 85% of the children given the full course of plasma-derived and yeast-derived hepatitis B vaccine from birth continued to have protective antibody to HBV two years after immunization. The programme is being closely monitored to assess the duration of immunity and the need for booster doses, while seronegative adults are also being encouraged to be vaccinated.     

围产儿与儿童胸腺的病理改变

The most outstanding pathological changes of perinatal babies and children, based on the review of the autopsy files in the 1st Affiliated Hospital of West China University of Medical Sciences, are lymphocytic depletion, and reticuloepithelial cell swelling and/or fusiform malformation in the cortex, while in the medulla apoptosis is more prominent. We suppose that these alterations are due to immaturity of cortical thymocytes, and in the diseased condition, they are easily affected by extraordinary factors, especially the influence of corticosterone inducing acute severe necrosis, so the number of lymphocytes are obviously diminished. But, in the medulla, as intact mature lymphocytes exist, physiological phenomenon such as apoptosis is rather prominent in it. While in the medulla, Hassall's corpuscles have various characteristic changes, such as cornification, calcification, fusion, cystic change and disintegration. Besides, we observed a new alteration in the thymus defined as vacuolization. All the above pathological changes reached the peak in the 28- day group; there after, they might become either worse or better according to the condition of the disease and growth of the body. However, these are still problems to be further studied separately.     

对中国药典诺氟沙星对照品在不同溶媒中的稳定性研究

目的：考察不同溶媒配制的诺氟沙星对照品溶液能否保存。方法：用紫外分光光度法分别对5℃放置的使用不同溶媒的对照品溶液在0d、10d、20d、30d、40d测定最大吸收波长、吸收值。结果；以0．4％NaOH溶液为溶媒的诺氟沙星对照液于5℃放置40d，最大吸收波长、吸收值均未发生变化（无显著性差异P＞0．05）。而以pH4.0醛酸缓冲液、pH7．4磷酸盐缓冲液为溶媒的两种对照液5℃放置40d，最大吸收波长未发生变化，但吸收值明显降低（有显著性差异P＜0．05）。结论：用0．4％NaOH溶液配制的诺氟沙星对照品溶液在适宜的条件下（5℃，避光密闭）保存，40d内是稳定的，可继续使用。而用pH4．0醋酸缓冲注和pH7．4磷酸盐缓冲液配制的诺氟沙星对照品溶液则不能保存使用，必须临用新配。     

An Analysis of Chromosome on Sterility Caused by Azoospermia or Oligospermia

ＡｎＡｎａｌｙｓｉｓｏｆＣｈｒｏｍｏｓｏｍｅｏｎＳｔｅｒｉｌｉｔｙＣａｕｓｅｄｂｙＡｚｏｏｓｐｅｒｍｉａｏｒＯｌｉｇｏｓｐｅｒｍｉａ￥ＷｕＭｅｉｈｅｎｇ；ＴａｎｇＷｉｎｇｎｕｏ．（ＡＣＴＡＡＣＡＤＥＭＩＡＥＭＥＤＩＣＩＮＡＥＮＡＮＪＩＮＧ，１９９５（...     

Photodynamic therapy inhibits transforming growth factor β activity associated with vascular smooth muscle cell injury

Purpose: The multifunctional cytokine, transforming growth factor β1 (TGF-β), plays an important role in the development of injury-associated intimal hyperplasia (IH). Strategies to suppress local TGF-β activity may have a clinical potential to prevent restenosis caused by IH. Photodynamic therapy (PDT) involves the local generation of cytotoxic free radicals by light activation of photosensitizer dyes and has been shown to inhibit experimental IH. This study investigated whether PDT-generated free radicals can affect TGF-β activity in a biologic system using vascular smooth muscle cells (SMCs).Methods: The release and activation of TGF-β by injured SMCs in culture was compared between mechanical injury and PDT. Mechanical injury was induced with a rubber policeman, and PDT was performed with the photosensitizer chloroaluminum sulfonated phthalocyanine (5 μg/ml) and 675 nm laser light at subtherapeutic 10 J/cm² and the in vivo therapeutic dose of 100 J/cm². Cell viability was assessed by the tetrazolium salt conversion assay, and active and total (active + latent) TGF-β was determined by enzyme-linked immunosorbent assay in the conditioned media of SMCs 24 hours after treatment. Functional TGF-β activity was assessed by inhibition of endothelial cell mitogenesis.Results: Both forms of injury severely reduced (p < 0.0005) SMC viability to less than 15%. In untreated SMC conditioned media, only 14.5% of the total TGF-β was active (27.7 ± 8.7 pg per 1 × 10⁵ cells). However, after mechanical injury and PDT with 10 J/cm², there was a significant increase (p < 0.02) in active TGF-β (60.1 ± 10.1 pg and 48.6 ± 21.0 pg, respectively), despite a total reduction of approximately 50%. In contrast to this result, PDT with 100 J/cm² did not result in increased levels of active TGF-β (8.1 ± 3.5 pg), despite having similar levels of total TGF-β. Consequently, the conditioned media of SMCs that had 100 J/cm² PDT did not inhibit endothelial cell mitogenesis as compared with the conditioned media of SMCs with mechanical injury and 10 J/cm² PDT (p < 0.0002).Conclusions: This report describes two novel findings: (1) injury to SMCs in vitro induces the conversion of biologically latent TGF-β to active TGF-β; and (2) the therapeutic PDT dose interferes with this injury activation process. This study substantiates the concept of local cytokine inhibition by PDT in a biologic system and provides new insights into the mechanisms of PDT-mediated inhibition of experimental IH. (J Vasc Surg 1997;25:1033-43.)     

~（99m）Tc－新半乳糖白蛋白体外受体介导结合特性的研究

本文报道￣９９ｍＴｃ－新半乳糖白蛋白（￣９９ｍＴｃ－ＮＧＡ）与大鼠肝细胞膜进行体外结合试验。结果表明：￣９９ｍＴｃ－ＮＧＡ系与肝细胞膜上的高亲和力低容量（Ｋ＿１：８．４０８９×１０￣９Ｌ／ｍｏｌ；Ｒ＿１：１．７３５０×１０￣（－１２）ｍｏｌ／ｍｇ）和低亲和力高容量（Ｋ＿２：２．０８２７×１０￣８Ｌ／ｍｏｌ；Ｒ＿２：６．９５３０×１０￣（－１２）ｍｏｌ／ｍｇ）２个结合位点相结合，其结合表现出高特异性、可饱和性及对细胞膜蛋白浓度的线性依赖性，具备受体介导结合的基本特征。￣（９９ｍ）Ｔｃ－ＮＧＡ是一个很有希望的肝受体显像剂。     

硫酸镍对红细胞毒性研究

健康小鼠腹腔注射硫酸镍10.0,5.0,2.5mg/kg,导致外周血中红细胞增高,血红蛋白不变或降低,红细胞中点彩红细胞和碱粒红细胞占有比值明显增高,网织红细胞含量升高、提示镍对外周血红细胞有毒性损害。