[HIV and syphilis infection and related medical treatment status of low-fee female sex workers in three provinces of China, 2012-2015].

Objective: To understand the HIV and syphilis infection and related treatment status of low-fee female sex workers (FSWs) in 3 provinces of China. Methods: Four cross-sectional survey data of low-fee FSWs from six cities (counties) in Guangxi, Yunnan and Hunan Province between October 2012 and July 2015 were obtained from the national science and technology major special project intervention study for reducing sexually transmitted diseases (STDs) and acquired immunodeficiency syndrome (AIDS) in low-fee FSWs' database, which included social demographic characteristics, sexual service characteristics and related medical care seeking behaviors, etc. A total of 2 050 subjects were included in the database. Results: The age of the subjects was (35.16±9.76) years old, with a minimum age of 15 and a maximum age of 67. Those who use condoms every time in commercial sex accounted for 58.9% (n=1 206). Among the reasons of not using condom, the proportion of client reluctant to use was the highest (81.0% (n=682)). Only 38.1% (n=782) was tested for HIV in the last six months. HIV confirmed positive rate was 6.8% (n=139), previous positive accounts for 76.3% (n=106). Rate of antiviral therapy was 55.4% (n=77). By the end of 2015, the loss rate of antivirus treatment was 18.2% (n=14). Those who self-reported symptoms of sexually transmitted diseases in the last 6 months accounted for 9.4% (n=191). 50.3% (n=96) of reporters chose to go to formal hospitals, 23.0% (n=44) chose to go to private clinics and 20.4% (n=39) chose their own medication. The syphilis infection rate was 13.5% (n=277), among them, 91.3% (n=253) were asymptomatic. Conclusion: Among low-fee FSWs, the rates of HIV and syphilis infection are higher, the condom consistent use rate, HIV antibodies and syphilis test rate are lower. In this group, active seeking medical idea is poor, the rate of anti-virus treatment and the rate of seeking medical treatment in formal medical institutions is low.

Activation of submucosal 5-HT(3) receptors elicits a somatostatin-dependent inhibition of ion secretion in rat colon.

BACKGROUND AND PURPOSE: 5-Hydroxytryptamine (5-HT) is a key regulator of the gastrointestinal system and we have shown that submucosal neuronal 5-HT(3) receptors exerted a novel inhibitory effect on colonic ion transport. The aim of the present study was to investigate the precise mechanism(s) underlying this inhibitory effect. EXPERIMENTAL APPROACH: Mucosa/submucosa or mucosa-only preparations from rat distal colon were mounted in Ussing chambers for measurement of short-circuit current (I(sc)) as an indicator of ion secretion. Somatostatin release was determined with radioimmunoassay. Intracellular cAMP content was measured with enzyme-linked immunoadsorbent assay (elisa). Immunohistochemical techniques were used to study the expression of 5-HT(3) receptors, somatostatin and somatostatin receptors in colonic tissue. KEY RESULTS: In rat distal colonic mucosa/submucosa preparations, pretreatment with 5-HT(3) receptor antagonists enhanced 5-HT-induced increases in I(sc). However, in mucosa-only preparations without retained neural elements, pretreatment with 5-HT(3) receptor antagonists inhibited 5-HT-induced DeltaI(sc). Pretreatment with a somatostatin-2 (sst(2)) receptor antagonist in mucosa/submucosa preparations augmented 5-HT-induced DeltaI(sc). Combination of sst(2) and 5-HT(3) receptor antagonists did not cause further enhancement of 5-HT-induced DeltaI(sc). Moreover, both sst(2) and 5-HT(3) receptor antagonists enhanced 5-HT-induced increase in intracellular cAMP concentration in the mucosa/submucosa preparations. 5-HT released somatostatin from rat colonic mucosa/submucosa preparations, an effect prevented by pretreatment with 5-HT(3) receptor antagonists. Immunohistochemical staining demonstrated the presence of 5-HT(3) receptors on submucosal somatostatin neurons and of sst(2) receptors on colonic mucosa. CONCLUSION AND IMPLICATIONS: Activation of neuronal 5-HT(3) receptors in the submucosal plexus of rat colon suppressed 5-HT-induced ion secretion by releasing somatostatin from submucosal neurons.