Transmission of HIV, hepatitis B virus, and other bloodborne pathogens in health care settings: a review of risk factors and guidelines for prevention. World Health Organization

Recent reports of the transmission of human immunodeficiency virus (HIV) in health care settings have caused considerable public health concern. HIV as well as hepatitis B virus (HBV) and other bloodborne pathogens do constitute infectious hazards in certain settings. Transmission has been reported from patient to patient, patient to health care workers, and rarely, from health care worker to patient. Although the risk of bloodborne pathogen transmission is largely preventable, it may occur due to the use of infected blood for transfusion, the use of improperly sterilized medical or dental equipment, and accidental punctures with contaminated instruments. The risk of transmission of bloodborne pathogens is dependent on a number of factors and appears to be greater for HBV than for HIV. General guidelines for the prevention of transmission in health care settings are given, including the concept of "universal precautions", the need for adequate supplies of sterile equipment, the reduction of unnecessary injections and transfusions, and the appropriate use of hepatitis B vaccine. In addition, areas for research are highlighted that could improve understanding of transmission risks in different health situations and provide the information necessary to develop more effective measures to protect both care providers and patients.     

Hemin enhances the in vitro growth of primitive erythroid progenitor cells

Since exogenous hemin has been shown to exert a variety of stimulatory effects on erythroid cells, including the augmentation of hemoglobin synthesis, we determined its effect on early stages of erythroid development by employing clonal cells assays. The addition of hemin at a concentration of 2 X 10(-4) M to cultures of normal murine marrow substantially increased the observed number of primitive BFU-E, which was in contrast to its lack of an effect on more mature erythroid colony-forming cells. This cell-specific enhancement of primitive BFU-E resulted in marrow frequencies equivalent to or exceeding those reported in the presence of "burst-promoting activity." In the presence of hemin, the number of BFU-E was also observed to be linearly related to the number of cells plated at very low plating densities, and the cell titration curve was observed to extrapolate to the origin. The evidence suggests that hemin may be a primary growth regulator of early developmental stages of erythroid progenitor cells.     

Contraception in China

Family planning has become general practice and a voluntary action by the majority of the Chinese people. A survey of contraceptive attitudes of people from street committees to the factory or commune revolutionary committees indicated that the most popular method of contraception is the low-dose oral contraceptive. Sterilization, although viewed as a crude solution, is a widely used alternative (30 percent male, 70 percent female). Other methods employed include the "paper pill," an experimental once-a-month pill, and injectables. The c oncept of late marriage and child spacing is encouraged. Group pressure persuading young people within the group to defer marriage and requirements establishing that candidates for further training should be unmarried act as disincentives to rapid family growth. In addition, target birth plans made by each area in China realistically influence individuals concerning contraception.     

Synthesis of deuterium‐labeled 3‐O‐methyldopa and 4‐O‐methyldopa

Concise methods for the synthesis of 4‐hydroxy‐3‐[²H₃]‐methoxyphenylalanine (3‐O‐[²H₃]‐methydopa) and 3‐hydroxy‐4‐[²H₃]‐methoxyphenylalanine (4‐O‐[²H₃]‐methydopa) are described. The 3‐O‐[²H₃]‐methydopa is a valuable internal standard for the tandem MS quantification of 3‐O‐methyldopa, a metabolite of value in the diagnosis of aromatic l‐amino acid decarboxylase (AADC) deficiency. Copyright © 2003 John Wiley & Sons, Ltd.     

Epothilones: mechanism of action and biologic activity.

Drugs that target microtubules are among the most commonly prescribed anticancer therapies. Although the mechanisms by which perturbation of microtubule function leads to selective death of cancer cells remain unclear, several new microtubule-targeting compounds are undergoing clinical testing. In part, these efforts focus on overcoming some of the problems associated with taxane-based therapies, including formulation and administration difficulties and susceptibility to resistance conferred by P-glycoprotein. Epothilones have emerged from these efforts as a promising new class of anticancer drugs. Preclinical studies indicate that epothilones bind to and stabilize microtubules in a manner similar but not identical to that of paclitaxel and that epothilones are effective in paclitaxel-resistant tumor models. Clinical phase I and early phase II data are available for BMS-247550, BMS-310705, EPO906, and KOS-862. The results suggest that these compounds have a broad range of antitumor activity at doses and schedules associated with tolerable side effects.     

Microvascular decompression for trigeminal neuralgia: report of outcome in patients over 65 years of age

Microvascular decompression (MVD) is now recognized as an effective operation for the cure of trigeminal neuralgia (TN), and is far superior to the other surgical procedures utilized in the treatment of TN. TN is common in the elderly, but there is debate concerning MVD in 'elderly' patients. Some clinicians have a policy of not offering patients over a certain age the choice of MVD, yet the recurrence rate is inversely related to the age of the patient. Previous failed procedures and a long period of pain before MVD, also affect the outcome negatively. This study is a retrospective review of the outcome in elderly patients following MVD. Forty-two patients over the age of 65 years are reviewed after undergoing MVD for TN. The results indicate that there was no serious morbidity or mortality that could be ascribed to old age and the length of stay in the hospital was not influenced by the age of the patient. The results are compared with the outcome in a younger age group and the literature on MVD for TN reviewed.     

Assessment of the mutagenicity of dichloroacetic acid in lacI transgenic B6C3F1 mouse liver

Dichloroacetic acid (DCA) is a chlorination byproduct found in finished drinking water. When administered in drinking water this chemical has been shown to produce hepatocellular adenomas and carcinomas in B6C3F1 mice over the animal's lifetime. In this study, we investigated whether mutant frequencies were increased in mouse liver using treatment protocols that yielded significant tumor induction. DCA was administered continuously at either 1.0 or 3.5 g/l in drinking water to male transgenic B6C3F1 mice harboring the bacterial lacI gene. Groups of five or six animals were killed at 4, 10 or 60 weeks and livers removed. At both 4 and 10 weeks of treatment, there was no significant difference in mutant frequency between the treated and control animals at either dose level. At 60 weeks, mice treated with 1.0 g/l DCA showed a 1.3-fold increase in mutant frequency over concurrent controls (P = 0.05). Mice treated with 3.5 g/l DCA for 60 weeks had a 2.3-fold increase in mutant frequency over the concurrent controls (P = 0.002). The mutation spectrum recovered from mice treated with 3.5 g/l DCA for 60 weeks contained G:C-->A:T transitions (32.79%) and G:C-->T:A transversions (21.31%). In contrast, G:C-->A:T transitions comprised 53.19% of the recovered mutants among control animals. Although only 19.15% of mutations among the controls were at T:A sites, 32.79% of the mutations from DCA-treated animals were at T:A sites. This is consistent with the previous observation that the proportion of mutations at T:A sites in codon 61 of the H-ras gene was increased in DCA-induced liver tumors in B6C3F1 mice. The present study demonstrates DCA-associated mutagenicity in the mouse liver under conditions in which DCA produces hepatic tumors.      

Fatty acid balance studies in term infants fed formula milk containing long-chain polyunsaturated fatty acids

Long-chain polyunsaturated fatty acids (LCP) are thought to be required for optimal nervous system development in the newborn. A commercial milk formula containing LCP (Aptamil-LCP) with a fatty acid profile closely resembling breast milk, has recently been introduced for term infants. The absorption of fatty acids in term infants was examined in a double-blind randomized controlled trial comparing Aptamil-LCP ( n = 20) and standard Aptamil ( n = 20). Formula-fed newborn infants were studied from birth for 14 d. Fat balances (3 d) were performed from d 10. A 3-d stool collection was performed from d 10 in a parallel breastfed group ( n = 21). Plasma samples were taken on d 6. Median fat excretion (mg kg⁻¹) was 897.1, 615.0 and 355.2 with Aptamil, Aptamil-LCP and breastfeeding, respectively. The median total fat absorption coefficient in Aptamil-LCP-fed infants was higher than in those fed standard Aptamil ( p < 0:01). These findings were accounted for by differences in the excretion and absorption of long-chain saturated fatty acids (C14:0, C16:0 and C18:0). Higher fat excretion was associated with bulkier and firmer stools. Only trace amounts of LCP were detected in the stools of all groups. This accounted for less than 4% of dietary intake in Aptamil-LCP-fed infants. No differences in the utilization of LCP from Aptamil-LCP and breast milk feeding were apparent. Plasma phospholipid fatty acid composition data reflected differences in dietary LCP intake. Thus, PL LCP levels were highest in the breastfed infants and lowest in the Aptamil-fed infants, with values for the Aptamil-LCP-fed group falling in between.