Efficacy of a hepatitis C virus core antigen enzyme-linked immunosorbent assay for the identification of 'window-phase' blood donations

BACKGROUND AND OBJECTIVES: Recent studies have suggested that potentially infectious donations provided during the antibody-negative 'window' phase of hepatitis C virus (HCV) infection may be identified by testing for viral RNA or HCV core protein. We therefore evaluated the performance of an HCV antigen enzyme-linked immunosorbent assay (ELISA) for identification of window-phase donations and for prospective screening of blood donors. MATERIALS AND METHODS: One-hundred and twenty-eight archived plasma donations containing HCV RNA, but lacking antibody to HCV (anti-HCV), were tested by using the HCV antigen ELISA, together with 9951 freshly collected serum and plasma specimens from blood donors. RESULTS: HCV core antigen was detected in 94% (120/128) of window-phase plasma donations. Overall specificity in freshly collected blood donor specimens was 99.74%. Two putative window-phase donations containing HCV core protein and viral RNA were identified from paid plasma donors by prospective testing with the HCV antigen ELISA. CONCLUSION: These results indicate that an HCV antigen ELISA can identify almost all (94%) of viraemic donations given during the seronegative window phase of infection. The performance of the HCV antigen ELISA appears to be suitable for large-scale screening of blood donations.     

Pressure-volume curves in acute respiratory distress syndrome: clinical demonstration of the influence of expiratory flow limitation on the initial slope

The presence of an initial segment with a low compliance on the static pressure-volume (PV) curve in patients with acute respiratory distress syndrome (ARDS) indicates that some lung compartments do not initially receive insufflated gas. We tested the hypothesis that an uneven distribution of time constants, producing a "slow compartment," was in part responsible for the change in compliance between the initial and the intermediate segment of the PV curve. In 16 patients with ARDS submitted to mechanical ventilation in volume-controlled mode with a supportive respiratory rate of 15 breaths/minute, we constructed the static PV curve on the first day of respiratory support and determined the intrinsic positive end-expiratory pressure (PEEPi4) during a prolonged end-expiratory pause (4 seconds). We also measured the volume of a "slow compartment" during a prolonged expiration (> 6 seconds), and determined an external PEEP (PEEPe) suppressing PEEPi4. Among the 16 patients studied, 11 exhibited a low inflection point, associated with a "slow compartment" of 172 +/- 83 ml, responsible for a PEEPi4 of 3 +/- 2 cm H2O. Conversely, the five remaining patients had a linear PV curve, associated with a minimal "slow compartment" of 28 +/- 10 ml, responsible for a negligible PEEPi4. We observed that individual slopes of the initial segment of the PV curve were inversely and significantly correlated with the proportion of the "slow compartment" (r = -0.85). We concluded that the shape of the inspiratory PV curve in ARDS might be dependent on the presence of a "slow compartment," and demonstrated that a low external PEEP appeared sufficient to achieve a substantial mechanical improvement in clinical practice.     

Effect of carvedilol on survival and hemodynamics in patients with atrial fibrillation and left ventricular dysfunction: retrospective analysis of the US Carvedilol Heart Failure Trials Program

BACKGROUND: Atrial fibrillation (AF) is present in a significant number of patients with congestive heart failure (CHF) caused by left ventricular dysfunction and is associated with significant morbidity and increased mortality rates. Thus it is necessary to establish therapy to improve the outcome in this high-risk population. METHODS: We conducted a retrospective analysis of data from the US Carvedilol Heart Failure Trials Program and identified patients with AF at the time of enrollment. In these trials, 1094 patients with at least 3 months of heart failure symptoms and an ejection fraction < or = 0.35 were randomly assigned to receive carvedilol or placebo in a double-blind, stratified program according to performance on an exercise test. RESULTS: One hundred thirty-six patients with concomitant AF and CHF were identified during the screening visit (84 assigned to carvedilol and 52 to placebo). Therapy with carvedilol resulted in a significant improvement in left ventricular ejection fraction (from 23% to 33% with carvedilol and from 24% to 27% with placebo, P =.001). The physician global assessment improved in a greater number of patients treated with carvedilol than in those treated with placebo (71% vs 48%, P =.025). A trend toward a reduction in the combined end point of death or CHF hospitalization was also observed (19% in patients treated with placebo and 7% in patients on carvedilol; relative risk, 0.35; 95% confidence interval, 0.12, 1.02; P =.055). CONCLUSIONS: In patients with AF complicating CHF, carvedilol significantly improves left ventricular ejection fraction and physician global assessment and probably reduces the combined end point of CHF hospitalizations or death.     

Melatonin prevents the free radical and MADD metabolic profiles induced by antituberculosis drugs in an animal model

The objective was to determine the effect of combined antituberculosis (anti-TB) drug therapy and an antioxidant, melatonin, on the free radical and organic acid profiles in an experimental rat model. A combined anti-TB drug, Rifater, consisting of 12.0 mg rifampicin, 0.8 mg isoniazid, and 23.0 mg pyrazinamide and 18.56 microg melatonin/kg body weight per day (corresponding to average physiological human intake) were orally administered to Sprague-Dawley rats. Hydroxyl radical production was monitored by quantifying 2,3-dihydroxybenzoic acid produced after intraperitonial sodium salicylate injections. Organic acid extractions and gas chromatography-coupled mass spectrometry analyses were performed on collected urine samples. The results show hydroxyl radicals (P = 0.0019) and organic acids (P-value range: 0.037 to <0.001), characteristic of a multiple acyl-CoA dehydrogenase defect (MADD), were elevated with Rifater treatment and these elevations were significantly lowered with melatonin pretreatment (P-value range: 0.031 to <0.001), probably because of its inherent antioxidant activity. We conclude that hydroxyl radical production and an increased organic acid profile induced by anti-TB medication indicates inhibition of the electron transport chain. We also conclude that free radicals leading to clinical symptoms associated with an MADD metabolic profile induced by anti-TB treatment could be alleviated by melatonin intervention.     

Closure of the pelvic and perineal wounds after removal of the rectum and anus

Between January 1975 and July 1977, 26 patients, who underwent combined synchronous removal of the rectum and anus, were managed within guidelines aimed at achieving primary closure and healing of their operative wounds. The guidelines include preoperative mechanical and luminal antibiotic bowel preparation, perioperative systemic chemoprophylaxis, a combined synchronous ablative procedure in Lloyd-Davies position, short-term sump drainage of the presacral space, meticulous hemostatis, and primary closure of both the pelvic defect above (utilizing an omental pedicle graft to obliterate the pelvic dead space) and the perineal defect below (by primary suture or with gracilis myocutaneous flap). All wounds healed totally within the first six weeks postoperatively, with a mean time to healing of 3.5 weeks in the six patients whose wounds failed to heal primarily. There were no instances of late wound breakdown with follow-up from six months to two years. Read at the meeting of the American Society of Colon and Rectal Surgeons, Atlanta, Georgia, June 10 to 14, 1979. The views expressed herein are those of the authors and do not necessarily represent the opinions of the United States Air Force.     

The effect of platelet-activating factor on histamine and muscarinic receptor function in guinea pig airways

Platelet-activating factor (PAF) administered i.v. or by aerosol to guinea pigs elicited an increase in airway responsiveness to both acetylcholine and histamine when compared with guinea pigs exposed to the vehicle bovine serum albumin (BSA). After i.v. PAF, the ED100 for acetylcholine and histamine was 5.4 and 3.4 micrograms/kg, respectively, in comparison with 17 and 6 micrograms/kg, respectively, before PAF, representing approximately a 3- and 2-fold increase in responsiveness, respectively. After aerosol PAF (500 micrograms), the ED100 for acetylcholine and histamine was 13 and 7 micrograms/kg, respectively, whereas after aerosolized BSA, the ED100 for acetylcholine and histamine was 23 and 12 micrograms/kg, respectively, representing approximately a 2-fold increase in responsiveness. However, airway smooth muscle obtained from these PAF- or BSA-treated animals did not exhibit any differences in contractile response to histamine or acetylcholine in vitro. Likewise, there were not significant differences in the binding affinity or receptor density between PAF- and BSA-treated tissues with [3H]quinuclidinylbenzilate or [3H]pyrilamine binding, which were used to identify muscarinic and H1-histamine receptors, respectively. Furthermore, histamine and carbachol-induced phosphoinositide hydrolysis was similar in PAF- and BSA-treated tracheal smooth muscle preparations. Thus, PAF induces airway hyperresponsiveness in the guinea pig that is not related to changes in airway smooth muscle or to changes in muscarinic and histamine (H1) receptor density or function.     

Comparison of interventions for pain control with tenaculum placement: a randomized clinical trial

Objective

Although previous studies have demonstrated that a variety of local anesthetics are effective to decrease pain associated with tenaculum placement, no studies directly compare an injection with a topical anesthetic. The objective of this study was therefore to compare mean pain scores with tenaculum placement after an intracervical lidocaine injection or topical lidocaine gel.

Study Design

A randomized, single-blinded trial of women presenting for office gynecologic procedures that required a tenaculum. Women aged 18 years or older were randomized to receive either a 1% lidocaine intracervical injection or topical application of 2% lidocaine gel to the cervix immediately prior to tenaculum placement. The primary outcome was pain at the time of tenaculum placement, measured on a 100 mm Visual Analog Scale. Secondary outcomes included pain with the intervention and satisfaction with tenaculum placement.

Results

Seventy-four women were enrolled and randomized; 35 subjects in each group met criteria for analysis. The two groups had similar socio-demographic characteristics. Women who received the injection had lower mean pain levels at tenaculum placement [12.3 mm (S.D. 17.4 mm) versus 36.6 mm (S.D. 23.0 mm), p<.001] but higher mean pain levels with study drug application [20.4 mm (S.D. 19.4 mm) versus 5.9 mm (S.D. 8.6 mm), p<.001]. Satisfaction with tenaculum placement was similar for the two groups.

Conclusion

Mean pain with tenaculum placement is lower after receiving a lidocaine injection than after receiving a topical lidocaine gel. Satisfaction with tenaculum placement is similar with both interventions.     

Assessing the feasibility of hepatitis C virus vaccine trials: Results from the Hepatitis C Incidence and Transmission Study-community (HITS-c) vaccine preparedness study

Efficacy trials of preventive hepatitis C virus (HCV) vaccine candidates raise challenging scientific and ethical issues. Based on data from the first 3 years of a community-based prospective observational study – the Hepatitis C Incidence and Transmission Study-community (HITS-c) – this paper examines the feasibility of conducting trials of candidate HCV vaccines with people who inject drugs (PWID) in Sydney, Australia. Of the 166 PWID confirmed HCV antibody negative and eligible for enrolment, 156 (94%) completed baseline procedures. Retention was high, with 89% of participants retained at 48 weeks and 76% of participants completing at least 75% of study visits within 2 weeks of schedule. The rate of primary HCV infection was 7.9/100 py (95% CI 4.9, 12.7). Of the 17 incident cases, 16 completed at least one follow-up assessment and 12 (75%) had evidence of chronic viraemia with progression to chronic HCV infection estimated to be 6/100 py. Power calculations suggest a chronic HCV infection rate of at least 12/100 py (primary HCV infection rate 16/100 py) will be required for stand-alone trials of highly efficacious candidates designed to prevent chronic infection. However, elevated primary HCV infection was observed among participants not receiving opioid substitution therapy who reported heroin as the main drug injected (26.9/100 py, 95% CI 14.5, 50.0) and those who reported unstable housing (23.5/100 py, 95% CI 7.6, 72.8), daily or more frequent injecting (22.7/100 py, 95% CI 12.2, 42.2) and receptive syringe sharing (23.6/100 py, 95% CI 9.8, 56.7) in the 6 months prior to baseline. These data suggest that it is possible to recruit and retain at-risk PWID who adhere to study protocols and that modification of eligibility criteria may identify populations with sufficiently high HCV incidence. Results support the feasibility of large multi-centre HCV vaccine trials, including in the Australian setting.     

Cell Phone Utilization Among Foreign-Born Latinos: A Promising Tool for Dissemination of Health and HIV Information

Latinos in the US are disproportionately affected by HIV and are at risk for late presentation to care. Between June 2011 and January 2012, we conducted a cross-sectional survey of 209 Baltimore Latinos at community-based venues to evaluate the feasibility of using information communication technology-based interventions to improve access to HIV testing and education within the Spanish-speaking community in Baltimore. Participants had a median age of 33 years interquartile range (IQR) (IQR 28–42), 51.7 % were male, and 95.7 % were foreign-born. Approximately two-thirds (63.2 %) had been in the US less than 10 years and 70.1 % had been previously tested for HIV. Cell phone (92.3 %) and text messaging (74.2 %) was used more than Internet (52.2 %) or e-mail (42.8 %) (p < 0.01). In multivariate analysis, older age and lower education were associated with less utilization of Internet, e-mail and text messaging, but not cell phones. Interest was high for receiving health education (73.1 %), HIV education (70.2 %), and test results (68.8 %) via text messaging. Innovative cell phone-based communication interventions have the potential to link Latino migrants to HIV prevention, testing and treatment services.