Socio-demographic characteristics associated with HIV and syphilis seroreactivity among pregnant women in Blantyre,Malawi, 2000–2004

Objectives

We aimed to evaluate socio-demographic factors associated with HIV and syphilis seroreactivity in pregnant Malawians presenting for antenatal care in late third trimester of pregnancy.

Methods

Between December 2000 and March 2004 at Queen Elizabeth Central Hospital Blantyre, Malawi, we collected cross-sectional clinical and socioeconomic data from consenting women. HIV-1 status was determined using rapid HIV antibody tests and syphilis seroreactivity was determined using Rapid Plasma Reagin (RPR) and confirmed with Treponema pallidum hemagglutination assay (TPHA).

Results

Of 3,824 women screened for HIV, 1156 (30%) were HIV seropositive and 198 (5%) were RPR and TPHA seroreactive. In the multivariate analysis, HIV infection was positively associated with elevated socio-economic status, being formerly married, and age, but not with education level. HIV prevalence was lower in women of Yao ethnicity than in other women (OR: 0.78, 95%CI: 0.64 – 0.95). Increased maternal education was negatively associated with syphilis seroreactivity.

Conclusions

The seroprevalence of HIV and syphilis among women attending the antenatal ward in Blantyre remains unacceptably high. Demographic correlates of HIV and syphilis infections were different. Our results demonstrate the need for better strategies to prevent HIV and syphilis in women and calls for optimizing antenatal syphilis screening and treatment in Malawi.     

Measurement of erythropoietin in anephric children

Serum erythropoietin (Ep) levels were measured using a highly sensitive radioimmunoassay in 69 children undergoing chronic dialysis; 31 were anephric, whereas 38 were non-nephrectomized (nephric). Twenty-nine normal children were studied as controls. Serum Ep levels in the anephric group were much higher than anticipated (mean 19.7±1.8 mU/ml), albeit significantly lower than those measured in normal children (mean 26.2±2.4 mU/ml,P<0.05), or in nephric children on dialysis (33.0±2.9 mU/ml,P<0.001). Anephric children on peritoneal dialysis (PD) had significantly (P<0.05) higher serum levels of Ep (22.7±2.4 mU/ml,n=19) than anephric children on hemodialysis (HD) (15.1±2.3 mU/ml,n=12). There was no significant difference between Ep levels in anephric patients dialyzed for less than or equal to 1 year (19.6±2.0 mU/ml,n=20) compared with anephric patients dialyzed for more than 1 year (20.0±3.9 mU/ml,n=11). Although serum Ep levels showed a tendency to increase with time after nephrectomy, the mean values for <3 months (14.7±1.9), 3 months–12 months (21.0±2.7), and >12 months (21.6±6.0) were not significantly different from each other. This demonstration of relatively normal levels of serum Ep in anephric children suggests that extrarenal sites of Ep production are able to exert a significant response to severe anemia in patients who are devoid of renal parenchyma.Table of SPNSG centers and investigators, and source of patients studied: Offprint requests to: R. J. Hogg, Department of Pediatrics, Baylor University Medical Center, 3500 Gaston Avenue, Dallas, TX, 75246, USA     

Intraoperative endoscopy of the biliary tract

Summary This is a prospective series of 328 operations for biliary stone disease in 326 consecutive patients. The overall operative mortality was 0.6%. Routine operative cholangiography was utilized during cholecystectomy, and this identified 19 patients (5.9%) with silent common bile duct stones. Common bile duct explorations were positive in 62 of 74 operations (83.8%). Biliary endoscopy was routinely performed during bile duct exploration. Unsuspected retained common duct stones were discovered postoperatively in 4.5% of these patients. Biliary endoscopy proved essential in the management of 18 patients with radiographically demonstrated distal bile duct obstruction. With patency confirmed by endoscopy, inappropriate duodenotomy and sphincter ablation were avoided in each of these 18 patients.     

A Randomized,Placebo-Controlled Study to Investigate the Safety,Tolerability, and Pharmacokinetics of 3 Weeks of Orally Administered Gefapixant in Healthy Younger and Older Adults

Purpose

Patients with chronic cough are typically female and have a mean age of?~?60 years. However, initial pharmacokinetic (PK) characterization of the P2X3-receptor antagonist gefapixant, developed to treat refractory or unexplained chronic cough, was performed in healthy participants who were predominantly younger adult males. The objective of this Phase 1 study was to assess the safety, tolerability, and PK of gefapixant in younger (18–55 years) and older (65–80 years) males and females.

Methods

A randomized, double-blind, placebo-controlled study was conducted. Healthy adult participants were stratified into 4 cohorts by age and sex (younger males/females and older males/females) and randomized 4:1 (younger adults) or 3:1 (older adults) to receive gefapixant 300 mg twice daily (BID) for 1 week, followed by gefapixant 600 mg BID for 2 weeks or placebo. Safety, tolerability, and PK were assessed.

Results

Of 36 randomized and treated participants, 28 (100%) receiving gefapixant and 6 (75%) receiving placebo reported?≥?1 adverse event (AE). The most common treatment-related AEs in the gefapixant group were taste related. Predefined renal/urologic AEs were reported by 7 (25%) participants receiving gefapixant (all mild to moderate in severity). Gefapixant exposure was generally lower in younger males compared with younger females and older adults; however, differences may have been due to estimated glomerular filtration rate.

Conclusion

The safety profile of gefapixant 300–600 mg BID was generally consistent with previous studies. Additional characterization of gefapixant PK as a function of age and sex using population PK modeling is warranted.

     

Noble-gas-infused neoprene closed-cell foams achieving ultra-low thermal conductivity fabrics

Closed-cell foams are widely applied as insulation and essential for the thermal management of protective garments for extreme environments. In this work, we develop and demonstrate a strategy for drastically reducing the thermal conductivity of a flexible, closed-cell polychloroprene foam to 0.031 ± 0.002 W m⁻¹ K⁻¹, approaching values of an air gap (0.027 W m⁻¹ K⁻¹) for an extended period of time (>10 hours), within a material capable of textile processing. Ultra-insulating neoprene materials are synthesized using high-pressure processing at 243 kPa in a high-molecular-weight gas environment, such as Ar, Kr, or Xe. A Fickian diffusion model describes both the mass infusion and thermal conductivity reduction of the foam as a function of processing time, predicting a 24–72 hour required exposure time for full charging of a 6 mm thick 5 cm diameter neoprene sample. These results enable waterproof textile insulation that approximates a wearable air gap. We demonstrate a wetsuit made of ultra-low thermally conductive neoprene capable of potentially extending dive times to 2–3 hours in water below 10 °C, compared with <1 hour for the state-of-the-art. This work introduces the prospect of effectively wearing a flexible air gap for thermal protection in harsh environments.

Herein, we develop, demonstrate, and model a repeatable process for synthesizing ultra-low-thermal-conductivity closed-cell neoprene garments by infusing high-molecular-weight noble gases.