Racial/ethnic differences in the risk of AIDS in the United States.

We analyzed the variation in the risk of AIDS in US Blacks, Hispanics, and other racial/ethnic groups relative to that in Whites (non-Hispanic) by geographic area and mode of acquiring HIV infection, based on data reported between June 1, 1981 and January 18, 1988 to the Centers for Disease Control and 1980 US census data. Relative risks (RRs) in Blacks and Hispanics were highest in the northeast region, and higher in suburbs than in central cities of metropolitan areas. RRs in Blacks and Hispanics were greatest for AIDS directly or indirectly associated with intravenous-drug abuse by heterosexuals (range: 5.7-26.9) and were also high for AIDS associated with male bisexuality (range: 2.5-4.8), suggesting that these behaviors may be more prevalent in Blacks and Hispanics than in Whites. Prevention strategies should take into account these racial/ethnic differences.     

Percutaneous nucleotomy: indications and preliminary results

Percutaneous nucleotomy was developed in the late seventies. In the beginning special forceps were used to remove the nuclear tissue. However, because of the large diameter of the cannulas used there was a risk of nerve damage. In 1985 Onik et al. presented the 'automated percutaneous lumbar diskectomy'. The risk of damage to the surrounding tissues of the disc was low. The method proved to be successful. In this article we describe the method and analyse our first 40 patients treated for a disc protrusion between February and June, 1988. This pilot study also shows that CT discography is important for the selection of patients for treatment with this method.     

Central tumour necrosis factor-α mediates the early gastrointestinal motor disturbances induced by lipopolysaccharide in sheep

Cytokines are involved in fever and other symptoms of the acute phase response induced by endotoxins. The aim of this work was to study the involvement of central tumour necrosis factor-alpha (TNF-alpha) in the changes induced by lipopolysaccharide (LPS) on gastrointestinal (GI) motility in sheep. Body temperature and myoelectric activity of the antrum, duodenum and jejunum was recorded continuously. Intravenous (i.v.) administration of LPS (0.1 micro g kg-1)-induced hyperthermia, decreased gastrointestinal myoelectric activity and increased the frequency of the migrating motor complex (MMC). These effects started 40-50 min after LPS and lasted for 6-7 h. TNF-alpha (50 and 100 ng kg-1) mimicked these effects when injected intracerebroventricularly (i.c.v.) but not i.v. Pretreatment with soluble recombinant TNF receptor (TNFR:Fc, 10 micro g kg-1, i.c.v.) abolished the TNF-induced actions and reduced those evoked by LPS. Furthermore, the effects induced by either LPS or TNF were suppressed by prior i.c.v. injection of indomethacin (100 micro g kg-1). In contrast, the i.v. injections of TNFR:Fc or indomethacin were ineffective. Our data suggest that LPS disturbs GI motility in sheep through a central pathway that involves TNF-alpha and prostaglandins sequentially.     

A torus palatinus with a family history

Summary Throughout history, different etiologies have been suggested for torus palatinus. In more recent years, however, torus palatinus has been attributed to heredity; a case which confirms this is presented. The relevant literature is reviewed.     

Behavioral effects of vehicles: DMSO, ethanol, Tween-20, Tween-80, and emulphor-620

Experimental drugs and compounds that do not easily dissolve in water or saline are frequently combined with vehicles like solvents, detergents, or vegetable oils. Yet very little has been reported on the behavioral effects of vehicles. In this study, we assessed the effects of a vegetable oil (emulphor-620), two detergents (Tween-20 and Tween-80), and two solvents [dimethyl sulphoxide (DMSO) and ethanol] on the locomotor activity in CD2F1 male mice. Locomotor activity was monitored for 12 h after vehicle administration (IP). The concentrations for each vehicle were expressed as percent of vehicle in saline (v/v). Emulphor-620 did not affect locomotor activity at any concentration tested (2%, 4%, 8%, 16%, and 32%). Tween-20 significantly decreased locomotor activity at a concentration of 16% and Tween-80 at 32%. DMSO significantly decreased locomotor activity at concentrations of 32% and 64%. In contrast, ethanol produced a biphasic behavioral response: increased activity at a concentration of 16% and decreased activity at a concentration of 32%. These results will facilitate the selection and concentration of vehicles to be used in combination with experimental drugs or test agents.     

Mercury from gold minings in the Pantanal of Pocone (Mato Grosso,Brazil)

The Pocone gold minings are situated in the Bento Gomes River Basin, at the border of the Pantanal of Mato Grosso. Gold-bearing quartz veins are removed from the subsoils, milled with water, centrifuged and the heavier fraction is subsequently mixed with mercury for gold separation. The gold mining activities caused a very intensive landscape change, threatening many environmental processes like sediment control and storage and recycling capacity of mercury. Cold Vapor Atomic Fluorescence System (CVAFS) was used to determinate total mercury in water, suspended material and sediments from Bento Gomes River, sampled monthly for 1 year. Apart from the fact that mercury concentrations are low in water and bottom sediments, they are slightly higher in relation to background levels measured in the area. The concentration in suspended material is also lower than other rivers with gold mining activities, but the floodplains of the Bento Gomes River act as mercury sinks. Therefore, the discharge of mercury into the Pantanal floodplain should be avoided, in spite of actual contamination of the system being very low.