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OBJECTIVES: The aim of the study was to investigate the hypothesis of accelerated cognitive ageing in HIV-positive individuals using longitudinal assessment of cognitive performance and quantitative magnetic resonance imaging (MRI). METHODS: We assessed a broad cognitive battery and quantitative MRI metrics [voxel-based morphometry (VBM) and diffusion tensor imaging (DTI)] in asymptomatic HIV-positive men who have sex with men (15 aged 20-40 years and 15 aged ≥ 50 years), and HIV-seronegative matched controls (nine aged 20-40 years and 16 aged ≥ 50 years). RESULTS: Being HIV positive was associated with greater decreases in executive function and global cognition. Additionally, using DTI, we found that the HIV-positive group had a greater increase in mean diffusivity, but we did not find group differences in volume change using VBM. With respect to the HIV status by age group interaction, this was statistically significant for change in global cognition, with older HIV-positive individuals showing greater global cognitive decline, but there were no significant interaction effects on other measures. Lastly, change in cognitive performance was correlated with change in the DTI measures, and this effect was stronger for the HIV-positive participants. CONCLUSIONS: In the present study, we found some evidence for accelerated ageing in HIV-positive individuals, with a statistically significant HIV status by age group interaction in global cognition, although this interaction could not be explained by the imaging findings. Moreover, we also found that change in cognitive performance was correlated with change in the DTI measures, and this effect was stronger for the HIV-positive participants. This will need replication in larger studies using a similarly lengthy follow-up period.

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The effects of supplementation with 1.5 mM n-acetyl-l-cysteine (NAC) during in vitro oocyte maturation were studied. Oocytes were supplemented with 1.5 mM NAC during maturation for 0 to 24 h, 24 to 48 h, or 0 to 48 h then subjected to IVF and embryo development. Oocytes were evaluated after maturation for intracellular glutathione concentration, superoxide dismutase and glutathione peroxidase activities and DNA fragmentation. Fertilisation and embryonic development success were also evaluated. There was no effect of treatment on intracellular glutathione concentrations, enzyme activities or fertilisation success rates. Supplementing NAC during maturation significantly decreased (P < 0.05) the percentage of oocytes with fragmented DNA compared with no NAC supplementation. Supplementing NAC from 24 to 48 h or 0 to 48 h resulted in a significantly higher (P < 0.05) percentage of oocytes with male pronuclei than for oocytes from the other treatment groups. There was no difference in the percentage of embryos cleaved by 48 h after IVF between treatment groups. Supplementing NAC from 24 to 48 h or 0 to 48 h resulted in a significantly higher (P < 0.05) percentage of embryos reaching the blastocyst stage by 144 h after IVF compared with the other treatment groups. These results indicate that supplementation of the oocyte maturation medium with 1.5 mM NAC, specifically during the last 24 h, improves male pronucleus formation and blastocyst development in pigs.

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The effects of 1.0 mmN-acetyl-l-cysteine (NAC) supplementation during the incubation of frozen-thawed and preserved boar sperm were studied in addition to subsequent oocyte IVF. Frozen-thawed and preserved boar sperm were supplemented with 1.0 mm NAC and incubated for 60 min to allow capacitation to occur followed by the addition of calcium ionophore 23187 to induce the acrosome reaction. The number of sperm having undergone the acrosome reaction was determined using the Wells-Awa staining technique. DNA damage was detected using single-cell gel electrophoresis. Membrane lipid peroxidation was estimated by the end point generation of malondialdehyde (MDA). Frozen-thawed sperm was not different in the ability of sperm to undergo the acrosome reaction but did have significantly (p < 0.05) more DNA damage (59.8 ± 1.0) compared to preserved sperm (32.0 ± 1.0%). Supplementing 1.0 mm NAC did not have an effect on the ability of sperm to undergo the acrosome reaction but did have significantly (p < 0.05) less DNA (39.2 ± 1.0%) damage compared to no antioxidant supplementation (52.7 ± 1.0%). Frozen-thawed sperm produced a significantly higher (p < 0.05) concentration of MDA (2.08 ± 0.05 µm MDA/10(7) cells) compared to preserved sperm (1.82 ± 0.05 µm MDA/10(7) cells), and non-supplemented sperm produced a significantly higher (p < 0.05) concentration of MDA (3.62 ± 0.05 µm MDA/10(7) cells) compared to the 1.0 mm NAC-supplemented sperm (0.28 ± 0.05 µm MDA/10(7) cells. Supplementation or semen storage method had no effect on IVF or embryonic development. These results indicate that supplementation with 1.0 mm NAC improved the ability to use frozen-thawed boar sperm during IVF as it reduces the DNA fragmentation and lipid peroxidation of the sperm.

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The cDNA sequence encoding the bovine fetal protein fetuin is reported. The deduced amino acid sequence is identical with that obtained from amino acid sequencing. The protein is a single chain preceded by a signal sequence. The three N-linked glycosylation sites have been determined. The sequence of fetuin shows over 70% similarity to human alpha 2HS glycoprotein. All of the cysteine residues are conserved in both proteins, suggesting that fetuin has the same arrangement of disulfide loops as alpha 2HS glycoprotein and may also be a member of the cystatin family. Southern blot analysis indicates that a single gene codes for fetuin. No evidence for a separate gene for a bovine alpha 2HS glycoprotein was obtained; thus, fetuin in cattle and alpha 2HS glycoprotein in the human are equivalent proteins.

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Rats chronically implanted with intrathecal catheters received intrathecal injections (10 microliters followed by 10 microliters saline flush) of either saline (n = 5), somatostatin (100 micrograms, n = 10), the somatostatin analog BIM 23003 (100 micrograms, n = 5), the somatostatin analog SMS 201-995 (100 micrograms, n = 5), the substance P analog [D-Pro2, D-Trp7,9] SP (10 micrograms, n = 10), or dynorphin A (1-17) (20 nmol, n = 8). These doses (somatostatin, substance P and dynorphin A) were selected based on previous studies in which they caused significant motor deficits. Effects on thermal cutaneous nociception, behavior, motor function and spinal cord histopathology were evaluated. All peptides caused severe neurotoxicity, evidenced by flaccid hind leg paralysis and lumbar spinal neuronal degeneration, which was accompanied by an inflammatory reaction in meninges and spinal gray matter. Histopathological changes had developed within 24 h after injection of somatostatin, substance P analog and dynorphin A, showing mild to severe neuronal degeneration and mild inflammatory responses in spinal cord and meninges. Significant antinociceptive effects, due to severe neurotoxic effects, were only observed following intrathecal injection of SMS 201-995 and the substance P analog. Potential neurotoxic mechanisms of the different peptides are discussed.

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Generally acid phosphatase (ACP) assay is used for testing cases of alleged rape. Comparison of three different chemical methods for Acid Phosphatase (Andersch's method with p-nitrophenyl-phosphate substrate and tartrate inhibitor (A-Tart), Roy's method with thymolphthalein phosphate substrate (R-TMP), and Babson's method with alphanaphthyl phosphate substrate) indicated that Roy's method (R-TMP) should be the preferred one. This method had both acceptable sensitivity and confirmed specificity. Our data confirmed that the vaginal wash of normal healthy women has a very low level of ACP activity. Because of inconclusive data in the literature regarding this ACP level, a normal and equivocal range of ACP was suggested until more is known about causes and interferences. Possible sources of normal ACP activity in the wash fluids were also indicated.

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