Involvement of progesterone and estrogen receptors in the ram sperm acrosome reaction.

The steroid hormones 17-ß estradiol (E2) and progesterone (P4) can regulate capacitation, hyperactive motility, and the acrosome reaction (AR) during the sperm transit through the female tract. Moreover, exogenous P4 and E2 can induce the AR in ovine spermatozoa, and progesterone receptor (PR) and estrogen receptors (ERα and ERß) are present in these cells. Thus, to investigate whether the effects both steroid hormones in ram sperm capacitation and AR are receptor-mediated, we incubated them with receptor agonists (tanaproget 1 µM and 5 µM for PR or resveratrol 5 µM and 10 µM for ER) or antagonists (mifepristone 4 µM and 40 µM for PR or tamoxifen 5 µM and 10 µM for ER) in capacitating conditions. The addition of receptor modulators did not affect sperm viability or total motility, although changes in progressive motility were detected. The incubation with both receptor agonists increased the percentage of acrosome-reacted spermatozoa, evaluated by chlortetracycline staining, when compared with the capacitated nontreated sample (Cap-C, P < 0.001). Moreover, the ER agonist resveratrol 10 µM provoked a greater AR than E2 (P < 0.01). Furthermore, the incubation with the receptor antagonists prevented the induction of the AR by P4 or E2, as the antagonists-treated spermatozoa presented a similar CTC pattern to that of Cap-C. In conclusion, these results confirm that P4 and E2 can induce the AR in ram spermatozoa and that this effect is receptor-mediated.

Plasma anti-serotonin and serotonin anti-idiotypic antibodies are elevated in panic disorder.

The psychoneuroimmunology of panic disorder is relatively unexplored. Alterations within brain stress systems that secondarily influence the immune system have been documented. A recent report indicated elevations of serotonin (5-HT) and ganglioside antibodies in patients with primary fibromyalgia, a condition with documented associations with panic disorder. In line with our interest in dysregulated 5-HT systems in panic disorder (PD), we wished to assess if antibodies directed at the 5-HT system were elevated in patients with PD in comparison to healthy volunteers. Sixty-three patients with panic disorder and 26 healthy volunteers were diagnosed by the SCID. Employing ELISA, we measured anti-5-HT and 5-HT anti-idiotypic antibodies (which are directed at 5-HT receptors). To include all subjects in one experiment, three different batches were run during the ELISA. Plasma serotonin anti-idiotypic antibodies: there was a significant group effect [patients > controls (p = .007)] and batch effect but no interaction. The mean effect size for the three batches was .76. Following Z-score transformation of each separate batch and then combining all scores, patients demonstrated significantly elevated levels of plasma serotonin anti-idiotypic antibodies. Neither sex nor age as covariates affected the significance of the results. There was a strong correlation between anti-serotonin antibody and serotonin anti-idiotypic antibody measures. Plasma anti-serotonin antibodies: there was a significant diagnosis effect [patients > controls (p = .037)]. Mean effect size for the three batches was .52. Upon Z-score transformation, there was a diagnosis effect with antibody elevations in patients. Covaried for sex and age, the result falls below significance to trend levels. The data raise the possibility that psychoimmune dysfunction, specifically related to the 5-HT system, may be present in PD. Potential interruption of 5-HT neurotransmission through autoimmune mechanisms may be of pathophysiologic significance in certain patients with panic disorder. It remains to be demonstrated if the peripheral autoimmunity is representative of CNS 5-HT neuronal alterations. Replication appears warranted.

[Prevalence of human immunodeficiency virus infection and behaviors associated with its transmission among parenteral drug users selected on the street]. / Prevalencia de infección por el virus de la inmunodeficiencia humana y de los comportamientos asociados a su transmisión entre usuarios de drogas por vía parenteral seleccionados en la calle.

BACKGROUND: To estimate the prevalence of HIV infection and the associated risk behaviours among intravenous drug users not receiving treatment for their drug dependence. PATIENTS AND METHODS: A cross-sectional study of 200 intravenous drug users recruited from the streets of Barcelona in 1993. Information about the socio-demographic aspects and behaviours was obtained through a personal interview using a standardised questionnaire which was carried out by three ex-drug users. Saliva samples were used to determine anti HIV antibodies. RESULTS: The prevalence of HIV infection was 51%. 57% borrowed used syringes, 65% lended their syringes, and 41% practised back of frontloading. 85% if those who shared syringes always cleaned them, however 59% only used water. 78% had heterosexual relations, in 33% of the cases with a non-injecting sexual partner. 65% always used condoms with sexual clients although only 26% always used them with stable sexual partners and 36% with casual sexual partners. 78% had performed the HIV test and among those who knew they were seropositive, 40% had received some kind of health control in the last 6 months. Not having a legal income, injecting speedball or barbiturates, unknowing self HIV negative status and practicing forms of indirect sharing were found to be independently associated with syringe sharing. CONCLUSIONS: The high prevalence of HIV infection and associated risk behaviours highlights the need to increase and adapt the prevention efforts and investigation to this group. Social marginalization and poliuse of drugs should be addressed in HIV prevention programs.

Expression of polymorphic msp1beta genes during acute anaplasma Marginale rickettsemia.

Immunization of cattle with native MSP1 induces protection against Anaplasma marginale. The native immunogen is composed of a single MSP1a protein and multiple, undefined MSP1b polypeptides. In addition to the originally sequenced gene, designated msp1beta(F1), we identified three complete msp1beta genes in the Florida strain: msp1beta(F2), msp1beta(F3), and msp1beta(F4). Each of these polymorphic genes encodes a structurally unique MSP1b protein, and unique transcripts can be identified during acute A. marginale rickettsemia. The structural polymorphism is clustered in discrete variable regions, and each MSP1b protein results from a unique mosaic of five variable regions. Although each of the MSP1b proteins in the Florida strain contains epitopes recognized by serum antibody induced by protective immunization with the native MSP1 complex, the variable regions also include epitopes expressed by some but not all of the MSP1b proteins. These data support testing recombinant vaccines composed of the multiple antigenically and structurally unique MSP1b proteins combined with MSP1a in order to mimic the efficacy of native MSP1 immunization.