High-flow nasal oxygen in resource-constrained, non-intensive, high-care wards for COVID-19 acute hypoxaemic respiratory failure: Comparing outcomes of the first v. third waves at a tertiary centre in South Africa

Background

High-flow nasal oxygen (HFNO) is an accepted treatment for severe COVID-19-related acute hypoxaemic respiratory failure (AHRF).

Objectives

To determine whether treatment outcomes at Groote Schuur Hospital, Cape Town, South Africa, during the third COVID-19 wave would be affected by increased institutional experience and capacity for HNFO and more restrictive admission criteria for respiratory high-care wards and intensive care units.

Methods

We included consecutive patients with COVID-19-related AHRF treated with HFNO during the first and third COVID-19 waves. The primary endpoint was comparison of HFNO failure (composite of the need for intubation or death while on HFNO) between waves.

Results

A total of 744 patients were included: 343 in the first COVID-19 wave and 401 in the third. Patients treated with HFNO in the first wave were older (median (interquartile range) age 53 (46 - 61) years v. 47 (40 - 56) years; p<0.001), and had higher prevalences of diabetes (46.9% v. 36.9%; p=0.006), hypertension (51.0% v. 35.2%; p<0.001), obesity (33.5% v. 26.2%; p=0.029) and HIV infection (12.5% v. 5.5%; p<0.001). The partial pressure of arterial oxygen to fraction of inspired oxygen (PaO2 /FiO2 ) ratio at HFNO initiation and the ratio of oxygen saturation/FiO2 to respiratory rate within 6 hours (ROX-6 score) after HFNO commencement were lower in the first wave compared with the third (median 57.9 (47.3 - 74.3) mmHg v. 64.3 (51.2 - 79.0) mmHg; p=0.005 and 3.19 (2.37 - 3.77) v. 3.43 (2.93 - 4.00); p<0.001, respectively). The likelihood of HFNO failure (57.1% v. 59.6%; p=0.498) and mortality (46.9% v. 52.1%; p=0.159) did not differ significantly between the first and third waves.

Conclusion

Despite differences in patient characteristics, circulating viral variant and institutional experience with HFNO, treatment outcomes were very similar in the first and third COVID-19 waves. We conclude that once AHRF is established in COVID-19 pneumonia, the comorbidity profile and HFNO provider experience do not appear to affect outcome.

Study synopsis

What the study adds. This study adds to the body of evidence demonstrating the utility of high-flow nasal oxygen (HFNO) in avoiding invasive mechanical ventilation (IMV) in patients with severe COVID-19 hypoxaemic respiratory failure, and shows that this utility remained consistent across different waves of the COVID-19 pandemic.Implications of the study. In resource-constrained settings, HFNO is a feasible non-invasive alternative to IMV and can be employed with favourable and consistent outcomes outside traditional critical care wards. It also confirms that the degree of gas exchange abnormality, and not pre-existing patient-related factors, circulating wave variant or provider experience, is the main predictor of HFNO failure.

Evaluating newly approved drugs for multidrug-resistant tuberculosis (endTB): study protocol for an adaptive, multi-country randomized controlled trial

BACKGROUND

Treatment of multidrug- and rifampin-resistant tuberculosis (MDR/RR-TB) is expensive, labour-intensive, and associated with substantial adverse events and poor outcomes. While most MDR/RR-TB patients do not receive treatment, many who do are treated for 18 months or more. A shorter all-oral regimen is currently recommended for only a sub-set of MDR/RR-TB. Its use is only conditionally recommended because of very low-quality evidence underpinning the recommendation. Novel combinations of newer and repurposed drugs bring hope in the fight against MDR/RR-TB, but their use has not been optimized in all-oral, shorter regimens. This has greatly limited their impact on the burden of disease. There is, therefore, dire need for high-quality evidence on the performance of new, shortened, injectable-sparing regimens for MDR-TB which can be adapted to individual patients and different settings.

METHODS

endTB is a phase III, pragmatic, multi-country, adaptive, randomized, controlled, parallel, open-label clinical trial evaluating the efficacy and safety of shorter treatment regimens containing new drugs for patients with fluoroquinolone-susceptible, rifampin-resistant tuberculosis. Study participants are randomized to either the control arm, based on the current standard of care for MDR/RR-TB, or to one of five 39-week multi-drug regimens containing newly approved and repurposed drugs. Study participation in all arms lasts at least 73 and up to 104 weeks post-randomization. Randomization is response-adapted using interim Bayesian analysis of efficacy endpoints. The primary objective is to assess whether the efficacy of experimental regimens at 73 weeks is non-inferior to that of the control. A sample size of 750 patients across 6 arms affords at least 80% power to detect the non-inferiority of at least 1 (and up to 3) experimental regimens, with a one-sided alpha of 0.025 and a non-inferiority margin of 12%, against the control in both modified intention-to-treat and per protocol populations.

DISCUSSION

The lack of a safe and effective regimen that can be used in all patients is a major obstacle to delivering appropriate treatment to all patients with active MDR/RR-TB. Identifying multiple shorter, safe, and effective regimens has the potential to greatly reduce the burden of this deadly disease worldwide.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier NCT02754765. Registered on 28 April 2016; the record was last updated for study protocol version 3.3, on 27 August 2019.

Clinical perspectives on treatment of rifampicin-resistant/multidrug-resistant TB

Rapid diagnostics, newer drugs, repurposed medications, and shorter regimens have radically altered the landscape for treating rifampicin-resistant TB (RR-TB) and multidrug-resistant TB (MDR-TB). There are multiple ongoing clinical trials aiming to build a robust evidence base to guide RR/MDR-TB treatment, and both observational studies and programmatic data have contributed to advancing the treatment field. In December 2019, the WHO issued their second 'Rapid Communication´ related to RR-TB management. This reiterated their prior recommendation that a majority of people with RR/MDR-TB receive all-oral treatment regimens, and now allow for specific shorter duration regimens to be used programmatically as well. Many TB programs need clinical advice as they seek to roll out such regimens in their specific setting. In this Perspective, we highlight our early experiences and lessons learned from working with National TB Programs, adult and pediatric clinicians and civil society, in optimizing treatment of RR/MDR-TB, using shorter, highly-effective, oral regimens for the majority of people with RR/MDR-TB.

Utilization of peptide phage display to investigate hotspots on IL-17A and what it means for drug discovery

To date, IL-17A antibodies remain the only therapeutic approach to correct the abnormal activation of the IL-17A/IL-17R signaling complex. Why is it that despite the remarkable success of IL-17 antibodies, there is no small molecule antagonist of IL-17A in the clinic? Here we offer a unique approach to address this question. In order to understand the interaction of IL-17A with its receptor, we combined peptide discovery using phage display with HDX, crystallography, and functional assays to map and characterize hot regions that contribute to most of the energetics of the IL-17A/IL-17R interaction. These functional maps are proposed to serve as a guide to aid in the development of small molecules that bind to IL-17A and block its interaction with IL-17RA.

Breastfeeding in mothers with systemic lupus erythematosus

Introduction

Breastfeeding is known to improve the well-being of a mother and her infant, and about half of all new mothers breastfeed, but it is unknown how breastfeeding is pursued in systemic lupus erythematosus (SLE; lupus) patients. We sought to determine the rate of breastfeeding and the factors influencing this among women with lupus. In addition, we reassessed the current safety data in lactation of lupus medications.

Methods

Data were collected from lupus patients enrolled in a prospective registry who fulfilled the 2012 SLICC criteria, had a live birth, and for whom postpartum breastfeeding status was known. Data included physician assessments of lupus activity and medications, breastfeeding intentions during pregnancy and practice following pregnancy. The safety of medications in breastfed infants was assessed through a comprehensive review of LactMed, a national database about medications in lactation.

Results

A total of 51 pregnancies in 84 women with lupus were included in the study. Half of the lupus patients ( n = 25, 49%) chose to breastfeed. The rate of breastfeeding was not significantly affected by socioeconomic factors. In contrast, low postpartum lupus activity, term delivery, and a plan to breastfeed early in pregnancy were significantly associated with breastfeeding in lupus patients. In reviewing the most up-to-date data, the majority of lupus medications appear to have very minimal transfer into breast milk and are likely compatible with breastfeeding.

Conclusion

Half of women with lupus breastfed and most desire to breastfeed. Hydroxychloroquine, azathioprine, methotrexate, and prednisone have very limited transfer into breast milk and may be continued while breastfeeding.

Implementing rules to improve the quality of concept post-coordination with SNOMED CT

The use of SNOMED CT as a standard reference terminology enables interoperability between clinical systems. This reference tool provides a method for creating post-coordinated terms by users according to local needs. While the creation of these terms is free, there are a number of rules, as defined in the user manual of SNOMED CT that must be followed.The Hospital Italiano of Buenos Aires has a Terminology Server that encodes medical terms, using SNOMED CT as the reference vocabulary. An interoperability analysis performed with the Nebraska Medical Center in 2006 found a high error rate (26%) in post-coordinated terms. Therefore, we implemented an automatic system of rules within the Terminology Server as defined in the user manual. Following rules implementation, the error rate decreased from 26% to 2%.

Aeroallergen sensitization correlates with PC(20) and exhaled nitric oxide in subjects with mild-to-moderate asthma

BACKGROUND

Aeroallergen sensitization in adult asthmatic patients from a wide geographic area has not been correlated with patients' characteristics, markers of airways inflammation, and lung function.

OBJECTIVE

We assessed data obtained from the Asthma Clinical Research Network trials to determine the relationship of aeroallergen sensitization to age, sex, ethnicity, and markers of inflammation and airways function.

METHODS

Skin testing (14 epicutaneous) was performed on 1338 subjects with objectively diagnosed mild-to-moderate asthma from 11 Asthma Clinical Research Network studies. Skin testing used identical techniques and a quality assurance program to ensure uniformity across centers.

RESULTS

Ninety-five percent of the subjects had at least 1 positive skin test response. Of these, 14% had positive reactions to 1 or 2 allergens and 81% had positive reactions to 3 or more allergens, and 2% of subjects reacted only to seasonal allergens, 26% only to perennial allergens, and 67% to both. Increasing IgE and exhaled nitric oxide values, decreasing PC(20) values, and minority ethnicity significantly correlated with the number of positive skin test responses. Subjects with late-onset asthma were less likely to be sensitized; nonetheless, 89% of subjects older than 60 years had positive responses.

CONCLUSION

Ninety-five percent of patients with mild-to-moderate asthma might have an allergic component. Age does not significantly affect aeroallergen sensitization, but the pattern of allergic sensitization varies with ethnicity and geography. Measures used to characterize asthma, such as IgE, exhaled nitric oxide, and PC(20) values, are correlated with aeroallergen sensitization.

Role of mast cells in otitis media

BACKGROUND

New pathophysiologic concepts are needed to explain the clinically observed connection between the allergic diathesis and otitis media. Although mast cells, unlike lymphocytes, are common in the normal middle ear mucosa, their potential role in innate immunity of the middle ear and in the expression of inflammatory responses in that space to bacterial challenge, as opposed to allergy, has received relatively little attention.

OBJECTIVE

In the current study, we examine the contributions of mast cells to the pathogenesis of bacterially induced inflammation in the middle ear and thus to otitis media.

METHODS

Wild-type mice, mast cell-deficient mice, and mast cell-deficient mice whose mast cell populations were restored by transplantation of bone marrow-derived mast cells were challenged by using models of bacterial and allergic middle ear inflammation.

RESULTS

Our results indicate that mast cells account for a substantial proportion of the innate immune response to bacteria in the middle ear.

CONCLUSION

This mechanism may link responses to allergy and infection in the middle ear mucosa, and thus the mast cell may be a critical control element in the pathogenesis of otitis media.

States respond to growing abuse of painkiller

OxyContin has been touted as a "miracle" drug for its abilities to ease chronic pain. But a growing number of addicts are obtaining it illegally because of the immediate, intense "high" it gives them.

Statistical Evaluation of Algebraic Constraints for Social Networks

A multirelational social network on a set of individuals may be represented as a collection of binary relations. Compound relations constructed from this collection represent various labeled paths linking individuals in the network. Since many models of interest for social networks can be formulated in terms of orderings among these labeled paths, we consider the problem of evaluating an hypothesized set of orderings, termed algebraic constraints. Each constraint takes the form of an hypothesized inclusion relation for a pair of labeled paths. In this paper, we establish conditions under which sets of such constraints may be regarded as partial algebras. We describe the structure of constraint sets and show that each corresponds to a subset of consistent relation bundles between pairs of individuals. We thereby construct measures of fit for a given constraint set. Then, we show how, in combination with the assumption of various conditional uniform multigraph distributions, these measures lead to a flexible approach to the evaluation of fit of an hypothesized constraint set. Several applications are presented and some possible extensions of the approach are briefly discussed. Copyright 2000 Academic Press.

Logit models and logistic regressions for social networks: II. Multivariate relations

The research described here builds on our previous work by generalizing the univariate models described there to models for multivariate relations. This family, labelled p*, generalizes the Markov random graphs of Frank and Strauss, which were further developed by them and others, building on Besag's ideas on estimation. These models were first used to model random variables embedded in lattices by Ising, and have been quite common in the study of spatial data. Here, they are applied to the statistical analysis of multigraphs, in general, and the analysis of multivariate social networks, in particular. In this paper, we show how to formulate models for multivariate social networks by considering a range of theoretical claims about social structure. We illustrate the models by developing structural models for several multivariate networks.

Psychiatry and children in the child welfare system

The child welfare system is, for better or worse, an unavoidable associate of the child and adolescent psychiatrist. Although the child psychiatrist rarely plays an integral role in decision making about the children who are involved with the system, the authors point out that a large percentage of children maintained in and involved with the system have psychiatric and developmental disorders. When these children's difficulties are either minimized or unrecognized by child welfare workers, the interventions and treatment that the children receive may be inappropriate. Worse still, when the children's difficulties are improperly addressed, the vicissitudes of the system may further harm them. The authors propose several ways in which the child and adolescent psychiatrist can have an important reparative role and voice in child welfare systems.

FH proteins as cytoskeletal organizers

Regulation of cell shape is a poorly understood yet central issue in cell biology. Recent experiments indicate that FH proteins link cellular signalling pathways to changes in cell shape. Members of the FH protein family play essential roles in cytokinesis and in driving alterations in cell polarity. This review discusses the structure and function of these proteins and examines the evidence that they interact specifically with Rho GTPases and profilin to organize the actin-based cytoskeleton.

Regulation and execution of meiosis in Drosophila males

In this chapter we review the regulation and execution of the meiotic cell divisions in the context of the developmental program that comprises Drosophila spermatogenesis. Male germ line cells undergoing meiosis are readily identifiable and are of a size and abundance that makes this system well suited for morphological characterizations of cell division. Furthermore, a wide range of molecular genetic techniques are available, facilitating mechanistic investigations. We present an overview of key stages in spermatogenesis and, in particular, meiosis. We consider the pathways controlling entry into the meiotic divisions in the context of established cell cycle regulators as well as newly identified loci required for meiotic entry. We then review the assembly and function of both the meiotic spindle and the contractile ring. We conclude with a consideration of questions and problems that await further investigation.

Latex allergy: epidemiological study of 1351 hospital workers

OBJECTIVE

To determine the prevalence of latex sensitisation among a large group of healthcare workers, study the occupational and non-occupational factors associated with latex allergy, and characterise latex exposure in air and by gloves.

METHODS

All 2062 employees of a general hospital in Hamilton, Ontario, Canada who regularly used latex gloves were invited to participate in a cross sectional survey, representing the baseline phase of a prospective cohort morbidity study. Attempts were made to recruit employees who were diagnosed with latex allergy before the survey. Glove extracts were assayed for antigenic protein, and area and personal air samples were obtained on two occasions (summer and winter) to estimate exposure to airborne latex protein. A questionnaire on medical and occupational information was administered by an interviewer. Skin prick tests were performed with latex reagents, three common inhalants, and six foods.

RESULTS

The mean (SD) latex protein concentrations were 324 (227) micrograms/g in powdered surgical gloves and 198 (104) micrograms/g in powdered examination gloves. Personal latex aeroallergen concentrations ranged from 5 to 616 ng/m3. There was a total of 1351 (66%) participants. The prevalence of positive latex skin tests was 12.1% (95% confidence interval (95% CI) 10.3% to 13.9%). This prevalence did not vary by sex, age, hospital, or smoking status but subjects who were latex positive were significantly more likely to be atopic (P < 0.01). Participants who were latex positive were also significantly more likely to have positive skin tests to one or more foods (Mantel-Haenszel odds ratio (OR) adjusted for atopy 12.1, 95% CI 7.6 to 19.6, P < 10(-9)). Work related symptoms were more often reported among latex positive people, and included hives (OR 6.3, 95% CI 3.2 to 12.5), eye symptoms (OR 1.9, 95% CI 1.2 to 2.8), and wheezy or whistling chest (OR 4.7, 95% CI 2.8 to 7.9). The prevalence of latex sensitivity was highest among laboratory workers (16.9%), and nurses and physicians (13.3%). When the glove consumption per healthcare worker for each department was grouped into tertiles, the prevalence of latex skin test positivity was greater in the higher tertiles of glove use for sterile (surgical) gloves (P < 0.005) but not for examination gloves.

CONCLUSIONS

In this large, cross sectional study of healthcare workers, the prevalence of latex sensitisation was 12.1% (9.5% among all those eligible), and there were significant associations with atopy, positive skin tests to certain foods, work related symptoms, and departmental use of gloves per healthcare worker. This cohort is being followed up prospectively and will be retested to determine the incidence of development of latex sensitivity.

Low risk of urinary incontinence following prostate brachytherapy in patients with a prior transurethral prostate resection

PURPOSE

To review post implant morbidity in patients with prior transurethral prostate resection (TURP).

METHODS AND MATERIALS

Nineteen patients with stage T1-T2 prostatic carcinoma and prior TURP were treated with I-125 or Pd-103 implantation from 1991 through 1994. Follow-up ranged from 1 to 6 years (median: 3 years). The time from TURP to implantation ranged from 2 months to 15 years (median: 3 years).

RESULTS

Only one patient developed mild urinary stress incontinence, 6 months following his I-125 implant. The actuarial freedom from permanent urinary incontinence at 3 years after implantation was 94%. No patient required urethral dilatation for urethral stricture. Eleven patients were sexually potent prior to implantation. At 3 years after treatment, all patients had maintained potency.

CONCLUSION

In our experience, there has been remarkably little adverse sequelae following I-125 or Pd-103 implantation in patients with a prior history of TURP.

103Pd brachytherapy and external beam irradiation for clinically localized, high-risk prostatic carcinoma

PURPOSE

To summarize biochemical failure rates and morbidity of external beam irradiation (EBRT) combined with palladium (103Pd) boost for clinically localized high-risk prostate carcinoma.

METHODS AND MATERIALS

Seventy-three consecutive patients with stage T2a-T3 prostatic carcinoma were treated from 1991 through 1994. Each patient had at least one of the following risk factors for extracapsular disease extension: Stage T2b or greater (71 patients), Gleason score 7-10 (40 patients), prostate specific antigen (PSA) > 15 (32 patients), or elevated prostatic acid phosphatase (PAP) (17 patients). Patients received 41 Gy EBRT to a limited pelvic field, followed 4 weeks later by a 103Pd boost (prescription dose: 80 Gy). Biochemical failure was defined as a PSA greater than 1.0 ng/ml (normal < 4.0 ng/ml). Patients whose PSA was still decreasing at the last follow-up were censored at that time. Patients whose PSA plateaued at a value greater than 1.0 were scored as failures at the time the PSA first plateaued.

RESULTS

The overall, actuarial freedom from biochemical failure at 3 years after treatment was 79%. In Cox proportional hazard multivariate analysis, the strongest predictor of failure was elevated acid phosphatase (p = 0.04), followed by PSA (p = 0.17), Stage (p = 0.23), and Gleason score (p = 0.6). Treatment-related morbidity was usually limited to temporary, RTOG Grade 1-2 urinary symptoms. One patient, who had both a transurethral incision of the prostate (TUIP) and a transurethral resection of the prostate (TURP), developed low-volume urinary incontinence. The actuarial potency rate at 3 years after implantation was 77% for 46 patients who were sexually potent prior to implant.

CONCLUSION

Biochemical freedom from failure rates following combined EBRT and 103Pd brachytherapy for clinically localized, high-risk prostate cancer compare favorably with that reported after conventional dose EBRT alone. Morbidity has been acceptable.

Evaluation of household dust mite exposure and levels of specific IgE and IgG antibodies in asthmatic patients enrolled in a trial of immunotherapy

BACKGROUND

Monitoring the response to immunotherapy entails understanding exposure to relevant allergens. For the major indoor allergens, this requires sampling of dust from the patient's house. The objectives of this study were to measure indoor allergen levels during a controlled trial of dust mite immunotherapy for asthma and to relate these results to serum antibody levels.

METHODS

Eighty-eight asthmatic patients with mite allergy from seven geographic areas in the United States were enrolled in and completed a course of immunotherapy with Dermatophagoides extract or placebo control. Sensitization was evaluated by quantitative measurements of IgG and IgE antibodies. Dust samples were assayed for group I mite (Der p 1 and Der f 1), cat (Fel d 1), and cockroach (Bla g 1) allergens by monoclonal antibody-based ELISA.

RESULTS

Over the 4 years of the study, each of the houses had at least one sample that contained more than 2 micrograms of group I mite allergen per gram of dust. Mean mite allergen levels, however, varied over a wide range, from 0.2 microgram/gm or less to more than 50 micrograms/gm. IgE antibodies to mite were present in sera from 78% of the patients, whereas IgE antibodies to cat and cockroach allergens were found in sera from 34% and 11% of patients, respectively. Sixty-four percent of the patients had exposure and sensitization to mite, whereas the comparable figure for each of the other allergens was 5%.

CONCLUSIONS

Examination of the results suggested that allergen exposure, relative to a trial of immunotherapy, could be expressed as (1) the maximum level found in the house, (2) the percentage of sites having greater than 2 micrograms/gm, or (3) the mean value at the site with the maximum level. This report provides a background for evaluating the clinical results of immunotherapy in these patients and a model for the way in which sensitization and exposure should be monitored in studies of this kind.

Attenuated live cholera vaccine strain CVD 103-HgR elicits significantly higher serum vibriocidal antibody titers in persons of blood group O

Persons of blood group O are at increased risk of developing cholera gravis. In a randomized, placebo-controlled, double-blind safety-immunogenicity trial of live oral cholera vaccine CVD 103-HgR in 5- to 9-year-old Chilean children, vibriocidal antibody seroconversion (74% overall) did not differ by blood group. However, the reciprocal geometric mean titer (GMT) in blood group O vaccines (GMT = 486) was higher than that in non-O vaccines (GMT = 179) (P < 0.02).

Ordering gene function: the interpretation of epistasis in regulatory hierarchies

The order of action of genes in a regulatory hierarchy that is governed by a signal can often be determined by the method of epistasis analysis, in which the phenotype of a double mutant is compared with that of single mutants. The epistatic mutation may be in either the upstream or the downstream gene, depending on the nature of the two mutations and the type of regulation. Nevertheless, when the regulatory hierarchy satisfies certain conditions, simple rules allow the position of the epistatic locus in the pathway to be determined without detailed knowledge of the nature of the mutations, the pathway, or the molecular mechanism of regulation.

Successful treatment of low back pain and neck pain after a motor vehicle accident despite litigation

OBJECTIVE

This prospective study evaluated 39 consecutive patients with low back pain (LBP) or neck pain that resulted from a motor vehicle accident who had litigation pending.

METHODS

Patients completed a McGill Pain Questionnaire (MPQ) to quantify pain and an Oswestry Low Back Disability Questionnaire (OSW) to quantify function and were interviewed regarding medications and work status at initial and final visits.

RESULTS

Thirty-three patients completed an MPQ at initial and final visits. Pain decreased in 29 (88%) and increased in four (12%). Thirty-eight patients completed an OSW at initial and final visits. Function improved in 34 and worsened in four. The authors observed statistically significant improvements in pain, function, and medication use.

CONCLUSION

Patients with low back pain or neck pain resulting from a motor vehicle accident showed a statistically significant improvement with treatment despite ongoing litigation.

Efficacy of azithromycin for treating Babesia microti infection in the hamster model

Because of its prevalence and severity, Babesia microti infection is an important public health problem. The current treatment of choice is clindamycin plus quinine. However, in some cases other treatments are needed because of drug intolerance or relapse. The activity of azithromycin was investigated for treatment of babesiosis in the hamster model. All animals received vancomycin to prevent antibiotic-associated colitis. Quinine (250 mg/kg/day), azithromycin (150 mg/kg/day), and the combination of azithromycin and quinine were compared. A significant suppression of parasitemia was found in all treatment groups (combination had the greatest effect, followed by azithromycin, then quinine; P < .05). The mean survival was significantly prolonged in the combination group (P < .05). Azithromycin as monotherapy in a higher dose (300 mg/kg/day) also resulted in a significant prolongation of survival (P < .05). Spirogermanium and ciprofloxacin, which have been reported to have antimalarial activity, had no effect on parasitemia or survival in this experimental babesiosis model.

Beryllium disease screening in the ceramics industry. Blood lymphocyte test performance and exposure-disease relations

We identified nine new cases of biopsy-confirmed chronic beryllium disease among 505 employees and ex-employees in a company that had manufactured beryllia ceramics from 1958 through 1975. Of tests commonly used in medical surveillance, only a confirmed blood beryllium lymphocyte transformation test had a high positive predictive value for beryllium disease (100%). However, two beryllium disease cases had either a normal or inconsistently abnormal blood test and were identified for diagnostic workup by abnormal chest radiograph. The only risk factor for beryllium disease was beryllium exposure; smoking or allergic history did not affect risk. Degree of beryllium exposure was associated with disease rates, which ranged from 2.9% to 15.8% for beryllia-exposed subgroups. One case of beryllium disease occurred in a "dust-disturber" who did not report past beryllium exposure and who began employment 8 years after commercial beryllia production had stopped. Our data support efforts to prevent beryllium disease by lowering beryllium exposures and to identify subclinical and early disease by broad-based medical surveillance using the blood beryllium lymphocyte test and chest radiograph in beryllium-using industries.

Anti-CD4 antibodies are associated with HIV-1 seroconversion and may be detectable before anti-HIV-1 antibodies. The Multicenter AIDS Cohort Study

We examined the sera from 14 HIV-1 seroconverters for the presence of autoantibodies against CD4. Anti-CD4 antibodies were detected in the serum of 11 of 13 HIV-1-infected persons at the time of HIV-1 seroconversion. In 6 of 14 persons from whom a serum was obtained prior to HIV-1 seroconversion, anti-CD4 antibodies were found 90 to 540 days before antibodies to HIV-1 were detectable. In comparison, anti-CD4 antibodies were present in only 7 serum samples from 62 HIV-1 seronegative individuals, including 50 from a seronegative homosexual male cohort. These results suggest that anti-CD4 antibodies are generated in response to early HIV-1 infection and possibly could be used as a marker for HIV-1 infection in some infected persons who are seronegative for HIV-1.

Participation of Colorado pediatricians and family physicians in the Medicaid program

The Pediatric Health Policy Group of the University of Colorado Health Sciences Center (Denver) surveyed 650 family physicians and 296 pediatricians in 1988, with 50% of family physicians and 48% of pediatricians responding. Half of the pediatricians in private practice and 35% of family physicians in private practice accepted all children who were Medicaid beneficiaries into their practice; 42% of pediatricians and 50% of family physicians accepted all non-Medicaid patients but only some new Medicaid patients; and 8% of pediatricians and 15% of family physicians accepted new non-Medicaid patients but no Medicaid patients. Practice location was associated with the level of Medicaid participation for these primary care physicians: Significantly more rural pediatricians and family physicians than those with urban practices accepted Medicaid patients. The average reimbursement level for these physicians was shown to be an important determinant of whether physicians would accept Medicaid patients. Nonparticipatory physicians were more concerned about excessive paperwork compared with physicians with limited participation. Among physicians with limited participation, family physicians and pediatricians both cited problems of excessive paperwork, reimbursement delays, and retroactive denials of payment as important deterrents to accepting Medicaid patients.

Bootstrapping: applications to psychophysiology

This paper presents the statistical technique known as the bootstrap to the general audience of psychophysiologists. The bootstrap, introduced by Efron (1979), allows data analysts to study the distribution of sample statistics that might otherwise be too complicated to consider. The technique, which requires simple calculations, involves drawing repeated samples (with replacement) from the empirical--or the actual--data distribution and then building a distribution for a statistic by calculating a value of the statistic for each sample. The bootstrap can be used to obtain confidence intervals, standard errors, and even higher moments for the statistic. It is similar to the well-known jackknife of Quenouille and Tukey. After discussing the history and theory of both the bootstrap and the jackknife, we illustrate the use of the bootstrap in the statistical analysis of correlation coefficients and the general linear model.

Dynamic measurement of human capillary blood pressure

1. Capillary blood pressure was measured in man using a dynamic servo-nulling system and direct micropuncture. This enabled assessments of the normal variations in pressure which influence fluid filtration and reabsorption. 2. Seventy-eight capillaries in 19 subjects were punctured in one of three positions around the capillary loop with the hand at the level of the sternal angle. Mean pressure around the loop fell from 37.7 +/- 3.7 mmHg (arteriolar limb, mean +/- SEM, n = 12) to 19.4 +/- 1.0 mmHg (apex, n = 25) to 14.6 +/- 0.5 mmHg (venular limb, n = 41) at skin temperatures of 18.7-33.1 degrees C. These values agree closely with Landis' original studies in 1930 [E. Landis (1930) Heart, 15, 209-228]. 3. The mean filtration/reabsorption state of any particular capillary limb was not static because of cardiac, vasomotor and respiratory fluctuations in capillary pressure. From a total of 38 capillaries in which recordings were analysed for 30 s, the fluctuations in pressure were such that 27 capillaries probably had periods of both filtration and reabsorption. 4. Computerized superimposition and coherent averaging of trains of capillary pulses enabled an accurate description of the pulse waveform to be made in three capillaries. This was remarkably similar to waveforms from the radial artery, albeit at reduced amplitude (average 3.6 +/- 3.4 mmHg, mean +/- SD overall). The time for the pulse to travel between the radial artery and the finger capillary was approximately 10 ms, which implies a propagation velocity of several metres per second.(ABSTRACT TRUNCATED AT 250 WORDS)

The eosinophil and the lung

Current concepts regarding the morphology, constituents, distribution, and kinetics of the eosinophil allow an expanded understanding of the eosinophil's function in health and disease. In particular, certain eosinophil constituents may have beneficial effects (modulation of mast cell-dependent reactions and helminthotoxic properties), while others may produce detrimental effects (tissue destruction). Eosinophils may be clinically important in obstructive and infiltrative pulmonary diseases. In obstructive disease, a peripheral eosinophilia indicates reversibility, and the magnitude of the peripheral eosinophil count correlates with the severity of the reversible obstruction. Concerning infiltrative pulmonary disease, an updated classification of pulmonary infiltrates with eosinophilia, which is based on recognizable causes and syndromes, is presented, and allergic bronchopulmonary aspergillosis, chronic eosinophilic pneumonia, drug reactions, the hypereosinophilic syndrome, parasitic infestations, and the Churg-Strauss syndrome are specifically considered.

Choreic movements induced by the use of methadone

A 25-year-old man received methadone hydrochloride maintenance therapy for heroin addiction. Choreic movements involving the upper limbs, torso, and speech mechanisms developed. Discontinuation of methadone resulted in complete alleviation of the abnormal movements with no recurrence during the subsequent eight months. To our knowledge, this is the first recorded instance of a movement disorder induced by an opiate. The mechanisms by which drugs may after neurotransmitter relationships in the brain and produce symptoms of this type are discussed.