Estimating the number of people at risk for and living with HIV in China in 2005: methods and results.

BACKGROUND: No new estimates of HIV infection have been available for China since 2003. However, since then, data availability has increased dramatically. OBJECTIVES: To use internationally recommended methods to make new estimates of the number of people exposed to HIV in China, the number living with HIV, and the number of new HIV infections and deaths in 2005. METHODS: The UNAIDS Workbook method was adapted to meet the needs of China. Local data were used to estimate the size of each risk population and HIV prevalence by risk group for every prefecture. These estimates were combined into provincial and national estimates. The UNAIDS Estimates and Projections Package and Spectrum were used to derive estimates of incidence and mortality from prevalence data, taking into account treatment. RESULTS: It was estimated that 650,000 people are living with HIV/AIDS in China (range 540,000-760,000), of whom 70,000 were newly infected in 2005 (range 60,000-80,000). Between 20,000 and 30,000 people are estimated to have died of HIV in 2005. The new estimate compares with an estimate of 840,000 people living with HIV/AIDS in 2003 (range 650,000-1,020,000). The estimated number of infected former plasma donors fell from 199,000 to 55,000. Infections remain concentrated among drug injectors, those buying and selling sex, and men who have sex with men. CONCLUSION: The new estimates are based on a much wider range of surveillance data as well as mass screening of former plasma donors, and are made at the prefecture level. More limited data from high prevalence provincial surveillance sites led to past estimates that now seem too high. New infections outpace death, and the HIV epidemic in China is still growing.

The long-term effectiveness of hysteroscopic treatment of menorrhagia and leiomyomas.

One hundred fifty-six of 177 patients admitted to the St. Luke's/Roosevelt Hospital Center between November 1973 and November 1988 for hysteroscopic treatment of menorrhagia and/or uterine leiomyomas were followed for long-term complications and necessity for repeat surgery. Ninety-four patients underwent submucous resection alone and 62 patients underwent endometrial ablation with or without submucous resection. Among the submucous-resection group, 24.5% reported late postoperative problems and 15.9% underwent further surgery. After 9 years of followup, 83.9% of the patients had not required further surgery. Among the ablation group, 22.5% experienced recurrence of increased bleeding and 8.1% had another surgical procedure. After 6 years of follow-up, 91.3% of the patients had not required further surgery. Twenty-one patients became pregnant after submucous resection, with 18 infants delivered. No patients who underwent endometrial ablation became pregnant. This modality of treatment appears to be effective over the long term, although effectiveness appears to diminish with time.

Prostaglandins E and F in cervical mucus of pregnant women.

Cervical mucus concentrations of prostaglandins E (PGE) and F (PGF) were measured by radioimmunoassay in samples collected from 30 pregnant women. The amount of mucus that could be aspirated did not vary significantly at various stages of gestation and was 67 mg on the average. Concentrations of both prostaglandins were lowest in the first trimester and increased significantly during the second trimester. No significant further increase was observed during the third trimester. Serial samples taken from five women at approximately weekly intervals from the 35th to the 36th week onward did not show any significant increase toward term, although several individual samples had very high concentrations, suggesting that the prostaglandins were secreted into the cervical lumen in pulses. During the first and second trimester, the concentrations of PGE and PGF were similar, but during the third trimester PGF levels were significantly higher. The mean concentrations of PGE and PGF in cervical mucus during the second half of gestation were 10 to 20 times higher than their reported levels in amniotic fluid at the same stage, and in the range reported by others to be effective in modulating cervical tissue responses in vitro. Two to 4 hours after intercourse, prostaglandin concentrations in the cervical mucus were found to be about 10- to 50-fold higher than normal. The prostaglandins in cervical mucus may well participate in the gradual changes in the extracellular matrix of the cervix that result in the extensive remodeling of the cervix during pregnancy.

Effect of beta-mimetic tocolysis on cervical ripening and plasma prostaglandin F2 alpha metabolite after endocervical application of prostaglandin E2.

To suppress uterine contractions during cervical ripening induced by prostaglandin E2 (PGE2) gel, beta-mimetic drugs were given orally 30 minutes before PGE2 application to 17 patients with unripe cervix. This prevented the increase in contraction frequency observed during the first four hours after PGE2 application in 17 controls. Nevertheless, cervical ripening proceeded at a similar rate and the clinical outcome was comparable in both groups. Prostaglandin E2 application caused a transient rise in plasma levels of the PGE2 alpha metabolite (13,14-dihydro-15-keto), which was not prevented by pretreatment with beta-mimetics. Patients with premature rupture of the membranes had higher initial plasma PGF2 alpha metabolite levels than those with intact membranes but cervical ripening proceeded with the same rate, and the effect of beta-mimetics was the same in both groups. Thus, cervical ripening induced by PGE2 does not depend on uterine contractions, and increased production of PGF2 alpha is unrelated to the ripening process. There was no difference between the three beta-mimetic agents in the present study.

Plasma prostaglandin F2 alpha and plasma 13,14-dihydro-15-keto-prostaglandin F2 alpha levels in women during induction of labor with i.v. infusion of prostaglandin F2 alpha in relation to uterine contractions.

The concentrations of plasma PGF2 alpha and its main metabolite, 13,14-dihydro-15-keto-PGF2 alpha (PGFM) were measured in serial samples of blood collected in 10 pregnant women at term who were given iv infusions of low doses of PGF2 alpha for induction of labor. Six other women served as controls and were given saline infusions. Uterine contractions began with a mean latency of 62 min in the PGF2 alpha infused women, in controls uterine activity remained unchanged. Plasma PGFM levels had increased significantly 30 min after PGF2 alpha infusion began, rising thereafter in a dose dependent manner. Plasma PGF2 alpha also rose reaching a steady state at 2 hours. No significant changes were observed in the controls. The 6-h infusion resulted in delivery in 5 of the 10 women, in the 5 others the cervical scores increased only by 1.25 points on the average and further treatment was needed to achieve delivery, although prostanoid levels rose to similar levels in all. The data show that when uterine contractions are induced by systemic PGF2 alpha, the levels of PGFM are significantly raised. In spontaneous labor uterine contractions begin long before plasma PGFM rises. Thus, if endogenous PGF2 alpha generation is involved in the initiation of uterine contractions during spontaneous labor, it must be synthetized in the myometrium at quantities too low to raise the levels of circulating PGFM.

Prostaglandin F2 alpha, oxytocin, and uterine activation in hypertonic saline-induced abortions.

Intra-amniotic injections of hypertonic saline at midgestation induce uterine activity, which evolves into a laborlike pattern in less than 24 hours and is associated with progressive increase in uterine oxytocin response. This uterine activation occurred in the absence of a measurable increase in plasma 13,14-dihydro-15-keto-prostaglandin F2 alpha (PGFM). Only after 25 to 27 hours was a rise in plasma concentration of PGFM detected, which then increased in a parallel manner with cervical dilatation. By contrast, plasma oxytocin levels increased by almost 100% soon after the injection of hypertonic saline, declining to initial levels by 24 to 28 hours. Oxytocin infusion given after the intra-amniotic injection at rates resulting in about a fivefold increase in plasma oxytocin significantly accelerated cervical dilatation and the rise in plasma PGFM. Oxytocin infused before induction of abortion resulted in only a small and transient rise in plasma PGFM. Hypertonic saline injections thus increase the prostaglandin F2 alpha-stimulating action of oxytocin, which in turn may be responsible for the enhanced contractile response to the hormone. Myometrial activation after hypertonic saline injections is probably caused by an interaction of oxytocin and prostaglandin F2 alpha, and cervical dilatation depends on contractile activity and a critical increase in prostaglandin production.

PIP: Intraamniotic injections of hypertonic saline at midgestation induce uterine activity, which evolves into a laborlike pattern in less than 24 hours and is associated with progressive increase in uterine oxytocin response. The uterine activation occurred in 18 women in the absence of a measurable increase in plasma 13,14-dihydro-15-keto-prostaglandin F2alpha (PGFM). Only after 25-27 hours was a rise in plasma concentration of PGFM detected, which then increased in a parallel manner with cervical dilatation. By contrast, plasma oxytocin levels increased by almost 100% soon after the injection of hypertonic saline, declining to initial levels by 24-28 hours. Oxytocin infusions given after the intraamniotic injection at rates resulting in about a 5-fold increase in plasma oxytocin significantly accelerated cervical dilatation and the rise in plasma PGFM. Oxytocin infused before abortion induction resulted in anly a small and transient rise in plasma PGFM. Hypertonic saline injections thus increase the PGF2alpha stimulating action of oxytocin, which in turn may be responsible for the enhanced contractile response to the hormone. Myometrial activation after hypertonic saline injections is probably caused by an interaction of oxytocin and PGF2alpha and cervical dilatation depends on contractile activity and a critical increase in PG production.

Cervical ripening and plasma prostaglandin levels. Comparison of endocervical and extra-amniotic PGE2.

Two modes of cervical application of a gel containing PGE2 have been compared in a total of 30 patients with indication for induction of labor and unripe cervix. Fifteen patients had gel injected endocervically; in 10 patients the gel contained 400 micrograms PGE2, in 5 controls the gel was inactive. Fifteen subjects had a 15 ml Foley catheter passed through the cervix and placed extra-amniotically; in 10 of them 3 ml gel with 400 or 800 micrograms PGE2 was injected, while 5 controls received inactive gel. Plasma levels of 13,14-dihydro-15-keto-PGE2 alpha (PGFM) were measured in blood samples drawn before and 1/2, 1, 2, 4, 6, and 8 hours after gel application. Neither the Foley catheter nor the application of inactive gel caused significant changes in the cervical scores or the PGFM levels. PGE2 in the endocervix increased cervical scores without altering plasma PGFM levels. Extra-amniotic PGE2 caused a more rapid increase of the cervical scores and a progressive rise in PGFM levels. The plasma (PGFM) levels were found to be related to the degree and to the rate of cervical dilatation. The correlation with cervical dilatation was highly significant. Labor began spontaneously or after artificial rupture of the membranes in 80% of the extra-amniotic, and 50% of the endocervical PGE2-group, but in none of the controls. These data indicate that increased uterine PGF2 alpha production is not necessary for the early stages of cervical ripening, whereas dilatation beyond 4 cm does not proceed without such increase.

Stimulation of myometrial and decidual prostaglandin production by amniotic fluid from term, but not midtrimester pregnancies.

The effect of amniotic fluid obtained from second trimester (16-20 wks) and term pregnancies (38-41 wks) on the production of PGE and F by human amnion, decidua and myometrium at term was determined using tissue slices incubated in vitro. Midpregnancy amniotic fluid neither inhibited nor stimulated the prostanoid production by any of the tissues. In contrast, term amniotic fluid obtained before as well as after the onset of labor markedly increased the production of both PGE and PGF in decidua and myometrium from levels in Krebs solution. The prostanoid production (PGE + PGF) in amnion was not significantly increased but the proportion of PGF was raised during incubations in term amniotic fluid. In decidua and myometrium the increase in PGE and PGF production in term amniotic fluid was approximately 200 and 400 percent respectively, from control values in Krebs solution. We propose that the stimulatory activity in term amniotic fluid is responsible for the accelerated synthesis of prostaglandins after rupture of membranes, which is reflected in raised PGF metabolite levels in maternal circulation. It may also be the reason for the rise in amniotic fluid prostaglandin levels around the 35th week of gestation, and perhaps for the onset of labor.

Cervical ripening with intracervical prostaglandin-E2 gel. I. Clinical results and effect on plasma levels of oxytocin and 13,14-dihydro,15-ketoprostaglandin-F2 alpha.

Tylose gel containing 400 micrograms prostaglandin E2 in 3 ml gel was injected into the cervical canal of 20 patients with high-risk pregnancy and indication for induction of labor, but with unfavorable cervix. Ten were studied after the first gel application, five during repeat injection, and five after application of gel without PGE2. Blood samples were drawn serially during the first 8 hours for determination of oxytocin and 13,14-dihydro,15-ketoprostaglandin-F2 alpha (PGFM). The PGE2 gel increased the Bishop score within 8 hours in all patients; in half of them, artificial rupture of the membranes could be performed and labor induced without further gel application; in the others, it was repeated every 8 hours until a Bishop score of greater than or equal to 8 was achieved. Fourteen of the 15 PGE2-induced patients delivered vaginally. Mean PGFM levels did not increase significantly during the 8 hours of observation, but in patients who responded with rapid progression, an increase was seen after cervical dilation was 6 cm or more. The mean oxytocin levels increased within 60 minutes after PGE2 application and were increased for the remaining observation period. Application of inactive gel had no effect on cervical ripening nor on oxytocin or PGFM levels.

Effect of cervical application of prostaglandin (PG) E2 on plasma 13,14-dihydro-15-keto-PGF2 alpha and oxytocin in pregnant women at term.

The concentrations of 13,14-dihydro-15-keto-prostaglandin F2 alpha (PGFM) and oxytocin were measured by radioimmunoassay in the peripheral plasma of 21 women with low Bishop scores in whom cervical ripening and labour were induced with a cervical cap containing 1.5 mg of prostaglandin (PG) E2, left in place for 6 h. Blood samples were taken before and at 3, 6, 9 and 24 h after the cap was applied. Four women (control group) had a cap without PGE2. Labour began in 13 women receiving PGE2, 12 of whom were delivered within 24 h. In these women plasma PGFM rose progressively to levels seen during spontaneous labour, paralleling the changes in cervical dilatation. The increase became significant at 6 h, when cervical dilatation was 4.5 cm (SEM 0.5). Plasma oxytocin also increased significantly while the cap was in place and then decreased. Plasma PGFM and oxytocin did not change in the control subjects, and in the eight women needing further induction of labour the initial rises were transient and not statistically significant.