Patient and provider acceptance of oral HIV screening in a dental school setting

In 2006, the Centers for Disease Control and Prevention (CDC) recommended routine HIV screening in health care settings regardless of the patient's level of risk. This pilot study was developed in response to the suggestion by some health care professionals that dental settings would be appropriate for expansion of HIV testing. This project consisted of two parts: oral fluid HIV testing of patients in the clinic of a dental school and a survey of the clinical dental faculty members' attitudes about acceptability of routine HIV testing in the dental clinic. When patients' agreement to participate in oral fluid HIV testing was examined, 8.2 percent of the patients contacted by the clinic administration staff completed testing. When approached by a faculty member or student during the dental visit admission and tested during the dental visit, however, 88.2 percent completed testing. Of the faculty members who took the survey, 27.4 percent were neutral, 26.4 percent were somewhat in agreement, and 32.1 percent were willing to incorporate HIV testing into routine dental care. In this pilot study, HIV testing of dental patients was most successful when a dental care provider approached patients about testing. If consent was given, the testing was performed during the visit. For the faculty members, the major barrier to testing was a lack of protocol familiarity.

Twinning in human populations and in cattle exposed to air pollution from incinerators

Human populations and animals are often exposed to the airborne pollutants in plumes from incinerators. The incineration of chemical and other waste may release polychlorinated hydrocarbons, some of which have oestrogenic properties. Increased numbers of twins had been reported anecdotally in cattle at risk from plumes from two incinerators near the town of Bonnybridge in central Scotland and also in cattle near a chemical factory in Eire. It was decided to follow up these reports in central Scotland and also to test the hypothesis that the frequency of human twinning might be increased there. Data on human twin and single births in hospitals in central Scotland were obtained for the years 1975-83. The twinning rates in areas exposed to airborne pollution from incinerators were compared with the background rates present in neighbouring areas. Farmers provided information on calving among the herds of two farms close to the incinerators. The frequency of human twinning was increased, particularly after 1979, in the areas most at risk from air pollution from the incinerators. Among the dairy cattle, there was a dramatic increase in twinning at about the same time.

Mutations downstream of the polyadenylation site of a Xenopus beta-globin mRNA affect the position but not the efficiency of 3' processing

In order to identify nucleotide sequences required for efficient and accurate polyadenylation of mRNA precursors, we have constructed a series of mutations in the X. laevis beta 1-globin gene and analyzed transcripts produced upon microinjection into Xenopus oocytes. Small deletion and linker replacement mutations, which lie in the region from 8 to 39 bp downstream of the AATAAA sequence and which effectively remove previously identified second components of the polyadenylation signal, do not greatly reduce the efficiency of processing, but in some cases alter the precise site of cleavage. We conclude that sequences downstream of the polyadenylation site affect the position of 3' RNA processing, but have minimal effects on its efficiency.

Raised mortality from lung cancer and high sex ratios of births associated with industrial pollution

Geographical and temporal associations were shown between high mortality from lung cancer and a high sex ratio of births both in the town of Bathgate (Scotland) and in the area of that town which was most exposed to polluted air from a local steel foundry. These findings constituted a replication of a similar association in an adjacent town.

An unusual sex ratio of births in an industrial town with mortality problems

In a small industrial town in central Scotland, geographical and temporal relations were established between respiratory cancer and an abnormally high sex ratio of births. Various categories of mortality and the sex ratios of births showed comparable annual trends, and suggest a possible role of air pollution.

The organization of the tadpole and adult alpha globin genes of Xenopus laevis

Adult erythrocytes of X. laevis contain six electrophoretically resolvable globin polypeptides while tadpole erythrocytes contain four polypeptides, none of which comigrates with an adult protein. We show that three of the adult proteins are alpha globin polypeptides (alpha 1, alpha 2, alpha 3) and three are beta globin polypeptides (beta 1, beta 2, beta 3). We find that a tadpole alpha globin gene (alpha T1) is linked to the major adult locus in the sequence 5'-alpha T1-alpha 1-beta 1-3' with 5.2 kb separating alpha T1 from alpha 1. Another tadpole alpha globin gene (alpha T2) is linked to the minor adult locus in the sequence 5'-alpha T2-alpha 2-beta 2-3' with 10.7 kb separating alpha T2 from alpha 2. These linkage relationships are consistent with the major and minor loci having arisen by tetraploidization but the different separation of larval and adult globin genes at the two loci indicates the occurrence of some additional chromosomal rearrangement. Two alternative models are presented.

Characterization and transcription analysis of a cloned sequence derived from a major developmentally regulated mRNA of D. discoideum

The plasmid pDd 812 contains a portion of a poly(A)+ RNA sequence isolated from developing cells of the cellular slime mold Dictyostelium discoideum (Williams and Lloyd, 1979). The poly(A)+ RNA complementary to this plasmid shows an increase in concentration during the first 4 hr of development followed by a decrease in concentration during the following 4 hr. This RNA is very abundant after 3-4 hr of development, constituting at least 2% of the poly(A)+ RNA population. In this study, we demonstrate that this poly(A)+ RNA is an mRNA sequence by translating the RNA complementary to pDd 812 in a heterologous system. The mRNA directs the synthesis of a major polypeptide of 33,000 daltons and a minor polypeptide of 31,000 daltons. We have used the plasmid DNA immobilized on filters to analyze the transcription of this RNA sequence in isolated nuclei. The amount of transcript synthesized in nuclei isolated at various stages of development which was complementary to pDd 812 changed in the same way as did the cytoplasmic concentration of this RNA--that is, maximal transcription occurred after 3-4 hr of development. Because this result was observed using labeling periods as short as 5 min, we believe that this change is unlikely to reflect a change in the rate of processing of RNA. We interpret these results to indicate that, at least in part, the control of the synthesis of this RNA is at the level of gene transcription.