An epidemiologic analysis of Mycobacterium avium complex disease in homosexual men infected with human immunodeficiency virus type 1

Cofactors associated with the Mycobacterium avium complex (MAC) disease and its prognosis in incident cases of AIDS in homosexuals were studied. We compared 51 men in whom MAC disease developed as the initial AIDS-defining illness (termed AIDS illness hereafter); 157 men who had MAC disease subsequent to another AIDS illness; and 884 men who had only non-MAC AIDS illnesses. MAC disease was the initially diagnosed AIDS illness more often in Baltimore (6.9%) and Los Angeles (5.6%) than in Chicago (2.6%) and Pittsburgh (0) (P < .01). MAC disease also was a more common subsequent AIDS illness in Baltimore (14.3%) and Los Angeles (22.4%) than in Chicago (8.5%) and Pittsburgh (6.5%) (P < .0001). Prophylaxis for Pneumocystis carinii infection increased the occurrence of MAC disease as the initial AIDS illness (from 2.3% to 12.5%; P < .0001). A low white blood cell (WBC) count was slightly more predictive of MAC disease than was a low CD4+ cell count. At 0-6, 7-12, and 13-18 months before diagnosis, the WBC cell counts of 75.0%, 61.1%, and 50.0%, respectively, of those with MAC disease as the initial AIDS illness were < or = 3,400/microL. Men in whom cytomegalovirus disease developed were at higher risk for subsequent MAC disease (relative hazard = 2.65; P < .0001). MAC disease also increased the risk for subsequent cytomegalovirus disease (relative hazard = 3.96; P < .0001).

Vitamin E, pulmonary functions, and phagocyte-mediated oxidative stress in smokers and nonsmokers

Relationships among the plasma levels of vitamin E (VE), the numbers and prooxidative activities of circulating phagocytes, serum alpha-1-protease inhibitor (API), and pulmonary functions were investigated in 83 asymptomatic male cigarette smokers and 65 nonsmoking controls. Plasma levels of VE, of cholesterol, and of API were measured using high performance liquid chromatography, spectrophotometry, and nephelometry, respectively, whereas reactive oxidant (ROS) generation by activated blood phagocytes was measured using a whole blood luciginen-enhanced chemiluminescence method. Smoking was associated with significantly increased circulating neutrophil counts (p 0.0001), serum API (p 0.0001) and phagocyte-derived ROS-generation (p 0.0001), and decreased spirometric values (FEV1: p 0.0138 and FEF25-75: p 0.0654). Plasma VE and cholesterol levels were not significantly different between smokers and nonsmokers. However, in smokers both plasma VE and cholesterol correlated significantly and positively with serum API (r 0.24, p 0.03 and r 0.30, p 0.005, respectively), neutrophil counts (r 0.24, p 0.03 and r 0.25, p 0.03, respectively), and phagocyte-derived ROS-generation (r 0.32, p 0.003 and r 0.32, p 0.003, respectively), and significantly and inversely with FEV1 (r -0.23, p 0.03 and r -0.22, p 0.04, respectively) and FEF25-75 (r -0.32, p 0.003 and r -0.26, p 0.02, respectively). In nonsmokers plasma VE, but not cholesterol, was positively correlated with FEV1 (r 0.34, p 0.007) and FEF25-75 (r 0.40, p 0.001). The results suggest that VE protects the lungs of both smokers and nonsmokers and may act as a mobilizable antioxidant in response to smoking-induced oxidative stress.

Glucosyl diglyceride lipid structures in Deinococcus radiodurans

The structures of two lipids from the radiation-resistant bacterium Deinococcus radiodurans are reported here: 1,2-diacyl-3-alpha-glucopyranosyl-glycerol and 3-O-[6'-O-(1",2"-diacyl- 3"-phosphoglycerol)-alpha-glucopyranosyl]-1,2-diacylglycerol. These lipids are strikingly different from previously characterized polar lipids from this organism, in that they are not unique to the genus Deinococcus and indeed have counterparts in both gram-negative and gram-positive bacteria. Moreover, as examples of glucose-containing lipids, they further illustrate the diversity of carbohydrate-containing lipids in D. radiodurans, from which lipids containing galactose and N-acetylglucosamine have already been structurally characterized.

Investigating chronic symptoms in HIV: an opportunity for collaborative nursing research

Because of improved life expectancy for people with HIV infection, today's clinician needs to understand and manage chronic symptoms that limit function and quality of life. The authors describe two collaborative HIV symptom-management studies conducted by the Division of Intramural Research of the National Institute of Nursing Research. Studies such as these are necessary to provide nurses and other healthcare personnel with the knowledge essential for appropriate, comprehensive, and quality patient care.

Antibodies that block virus attachment to Vero cells are a major component of the human neutralizing antibody response against dengue virus type 2

Epidemiological data strongly implicate a role for the host humoral immune response in both protection against and exacerbation of dengue virus-caused disease. In an effort to characterize elements of the normal human immune response against dengue virus we have addressed the issue of antibody-mediated neutralization of dengue virus. We show here the ability of both mouse monoclonal antibody 3H5 and human anti-dengue neutralizing sera to block binding of dengue-2 virus to monkey kidney (Vero) cells. Since Vero cells possess virus receptors but not Fc receptors we conclude that the major effect of host neutralizing antibodies is to block virus attachment to Vero cell dengue virus receptors. Analysis of 61 patient antisera yielded good correlation (Pearson's coefficient = 0.90; P < 0.001) between neutralizing activity and ability to block virus-cell attachment suggesting that antibody-mediated neutralization of dengue virus occurs primarily extracellularly and less by a postattachment mechanism as has been described for certain other viruses.

Development of a guinea pig model to assess immunogenicity of Haemophilus influenzae type b capsular polysaccharide conjugate vaccines

There is currently no animal model which reliably predicts the immunogenicity of Haemophilus influenzae type b (Hib) polysaccharide-protein conjugate vaccines in human infants. We evaluated various Hib vaccines in guinea pigs using techniques similar to the United States potency test for adsorbed diphtheria and tetanus toxoids with a view to developing a method for evaluating the potency of a combined adsorbed tetanus, diphtheria, pertussis and Hib conjugate vaccine. Groups of 6-8 guinea pigs received 1.5 single human doses of vaccine at 0 and at 6 or 8 weeks and were bled at 6 weeks and 2 weeks after the booster injection. Total antibodies to polyribosylribitolphosphate (PRP), the Hib capsular polysaccharide, were measured in individual animals and in serum pools by radioimmunoassay. The relative antibody responses of guinea pigs to Hib conjugate vaccines qualitatively resembled those of human infants. Unconjugated polysaccharide was not immunogenic; PRP-D produced a low antibody response, HbOC, PRP-T (Merieux) and Hib-T (MPMBL) produced a low response to the first dose and a strong anamnestic response to the booster (geometric mean anti PRP > 1 micrograms ml-1). PRP-OMP uniquely produced a strong response after the first dose which was further boosted by the second dose. Experimental Hib-T vaccine lots with low levels of conjugation were poorly immunogenic in guinea pigs. Combinations of DTP and Hib-T vaccines showed equivalent or greater immunogenicity than Hib-T alone. We propose that the guinea pig model may be useful to verify the immunogenicity of PRP conjugate vaccines and for pre-clinical evaluations of DTP-Hib combination vaccines containing PRP conjugates.

Failure of high-dose oral acyclovir to suppress CMV viruria or induce ganciclovir-resistant CMV in HIV antibody positive patients

Ninety-three symptomatic HIV antibody positive patients were randomized to receive zidovudine (ZDV) 600 mg/day and acyclovir (ACV) 4,800 mg orally per day versus ZDV 600 mg/day plus placebo. Urine was obtained at 3-month intervals and cultured for cytomegalovirus (CMV) in diploid fibroblast cells. The percent of urine specimens positive for CMV was 7.1% in the ZDV group and 5.8% in the ZDV plus ACV group (p = 0.55); 27% of patients had at least one urine culture positive for CMV while taking ZDV, versus 20% of patients taking the combination of ZDV plus ACV (p = 0.52). We conclude that ACV at a dosage of 4,800 mg/day does not suppress CMV excretion in urine of symptomatic HIV antibody positive patients taking concurrent ZDV. Use of ACV did not appear to induce resistance of CMV to ganciclovir since the ID50 of isolates from the two treatment groups did not differ.

Relationship of sociotropy/autonomy and dependency/self-criticism to DSM-III-R personality disorders

Relationships between Beck's constructs of sociotropy/autonomy and Blatt's constructs of dependency/self-criticism and the Diagnostic and Statistical Manual of Mental Disorders (3rd ed., rev.; American Psychiatric Association, 1987) Axis II personality disorders were examined. Two measures of personality styles and a structured diagnostic interview for personality disorders were administered to 138 outpatients. Significant relationships were found between both sets of constructs and a number of personality disorders using both categorical and dimensional measures of Axis II psychopathology. These relationships were consistent with previous theory, supporting recent conceptualizations extending the range of psychopathology associated with these personality styles from depression to the personality disorders. However, the autonomy/self-criticism dimension was correlated with a broader range of personality disorder traits and diagnoses than anticipated.

Neutralization of respiratory syncytial virus after cell attachment

Little is known about the mechanisms of antibody-mediated neutralization of respiratory syncytial virus (RSV) which causes recurrent infections in human despite the virtually universal presence of neutralizing serum antibodies. Human serum neutralization titers showed strong correlation with post-cell-attachment neutralizing titers for both RSV-convalescent sera and control sera but showed less strong correlation with cell-attachment blocking titers. Neutralization was effective for the first 60 min of infection, indicating that immune serum-mediated neutralization of RSV infection largely involves inhibition of early events following cell attachment.

Optic nerve decompression in cranial base fibrous dysplasia

Fibrous dysplasia of the anterior cranial base involves the bony orbit and optic canal. Although fibrous dysplasia is benign, it may produce a mass effect along the course of the optic nerve, inducing visual disturbances. Optic canal decompression in patients without clinical signs of optic neuropathy is controversial. We describe five patients with extensive fibrous dysplasia of the anterior cranial base involving the orbit and optic canal. These patients underwent transcranial optic canal decompression before signs of severe visual loss during correction of dystopias and craniofacial deformity induced by fibrous dysplasia. Cranial orbital reconstruction was performed by means of split rib and cranial bone grafts. Postoperative follow-up did not reveal disturbances in visual function, extraocular motility, or evidence of cerebrospinal fluid fistulas. This suggests that early, radical resection of orbital fibrous dysplasia with optic canal decompression may be effective in preventing visual loss with minimal risk of other neurological sequelae. Subsequent orbital reconstruction involving split-thickness rib and cranial bone grafting yields satisfactory cosmetic results.

Expression of the Bordetella pertussis P.69 pertactin adhesin in Escherichia coli: fate of the carboxy-terminal domain

The mature pertactin protein (P.69) of Bordetella pertussis can be isolated from the bacterial cell surface as a polypeptide with an apparent molecular mass of 69,000 Da as determined by sodium dodecyl sulphate gel electrophoresis. However the open reading frame of prn, the pertactin gene, encodes a polypeptide with a predicted molecular mass of 93,478 Da, referred to as P.93. Expression of the prn gene in Escherichia coli leads to the synthesis of the full-length P.93 polypeptide, which is rapidly processed to the mature P.69 protein located at the cell surface. The P.93 precursor polypeptide is processed at both termini. A 34 amino acid long signal sequence is removed from the amino-terminus and a polypeptide sequence of about 30,000 Da (P.30) is cleaved from the carboxy-terminus. Deletion of the 3' region of prn, encoding P.30, results in the expression of an intracellular form of P.69. Antiserum which recognizes P.30 was raised using synthetic peptides based on the primary amino acid sequence of the region. This anti-P.30 serum was used in a Western blot analysis of fractionated cells of B. pertussis and E. coli harbouring the intact prn gene. The P.30 polypeptide was readily detected in outer membrane fractions prepared from both of these bacterial species, although it could not be shown to be exposed at the cell surface.

Characterization of the adenosine receptors mediating hypothermia in the conscious mouse

1. The effects of a range of adenosine receptor-selective ligands on body temperature were investigated following intracerebroventricular (i.c.v.) and intraperitoneal (i.p.) injection in conscious mice. The compounds tested were the non-selective adenosine receptor agonist 5'-N-ethyl-carboxamidoadenosine (NECA), the adenosine A1 receptor-selective agonists cyclopentyl-adenosine (CPA), N6-(9R-phenyl-isopropyl)-adenosine (R-PIA) and N-(1S,trans)-[2-hydroxyclopentyl]-adenosine (GR79236), the A2a receptor selective agonist 2-[p-(2-carboxyethyl)phenethylamino]-5'-N-ethylcarboxyamidoaden osine (CGS-21680), the A2b receptor agonist N-[(2-methylphenyl)methyl[adenosine (metrifudil) and the A3 receptor agonist N6-(4-aminophenylethyl)adenosine (APNEA). 2. NECA (0.01-1 microgram, i.c.v.), all of the A1-selective agonists (0.01-1 microgram, i.c.v.) and APNEA (0.1-3 micrograms i.c.v.) produced profound and dose-related hypothermia and sedation. However, CGS-21680 (0.1-10 micrograms i.c.v.) and metrifudil (0.01-1 microgram i.c.v.), produced only mild hypothermia at the highest doses tested. 3. The hypothermic response to the A1 receptor-selective agonists, GR79236 and R-PIA was dose-dependently antagonized by peripheral administration of either the non-selective adenosine receptor antagonist, 8-phenyltheophylline (8-PT, approximately 40 and 30 fold rightward shifts of the dose-response curves respectively at 10 mg kg-1, i.p.), or the adenosine A1 receptor-selective antagonist, 8-cyclopentyl-1,3-dipropylxanthine (DPCPX, approximately 20 fold shift of the GR79236 dose-response curve at 1 mg kg-1, i.p.). The hypothermic response to APNEA was similarly dose-dependently antagonized by the A1 receptor-selective antagonist, DPCPX (5 fold shift at 0.1 mg kg-1, i.p.). 4.8(p-Sulphophenyl)theophylline (8-SPT, 10 and 30 mg kg-1, i.p.), a non-selective adenosine receptorantagonist that penetrates the blood brain barrier poorly, produced only modest antagonism (approximately 2 fold shift at 30 mg kg-1, i.p.) of the hypothermic response to GR79236.5. These data suggest that hypothermia induced by adenosine analogues in the conscious mouse is mediated via adenosine A1 receptors, which are probably located in the CNS.

The WHO and why of HIV vaccine trials

A World Health Organization (WHO) advisory committee meeting in Geneva at the end of last month approved phase III trials for HIV vaccines in developing countries. What is the justification for this decision?

Antibody-dependent enhancement of respiratory syncytial virus infection by sera from young infants

Respiratory syncytial virus (RSV) convalescent-phase sera and control sera from both infants ( < 6 months) and older individuals (1.5 to 90 years) were assayed for RSV-specific antibodies by neutralization, in vitro enhancing activity, and immunoprecipitation. Enhancement of RSV infection in U937 cells was demonstrated with convalescent-phase sera and was shown to be dependent on Fc receptors by blocking with human immunoglobulin G (P < 0.01). Convalescent-phase sera from infants enhanced infection at concentrations closer to physiological ones (10(-1) to 10(-3) dilutions of serum), while convalescent-phase sera from older individuals enhanced infection only at much lower concentrations (10(-3) to 10(-6) dilutions of serum; P < 0.01). To our knowledge, this is the first report of RSV-enhancing antibody activity in the sera of infants. The observed enhancing activity and the low neutralizing antibody levels are confined mostly to convalescent-phase sera from infants aged 0 to 6 months, suggesting that these factors may contribute to the increased severity of RSV disease frequently encountered in young infants.

Comparison of the composition and opsonic activities of imported and South African-manufactured intravenous and intramuscular immunoglobulin preparations

We compared the composition and opsonic activities for two common microbial pathogens (Staphylococcus aureus and Streptococcus pyogenes) of various imported intravenous (IV) (Sandoglobulin, Octagam and Gammagard) and intramuscular (IM) (Beriglobin and Globuman Berna) immunoglobulin (Ig) preparations with those of the corresponding locally manufactured products, Polygam (IV) and Intragam (IM). When tested at equivalent concentrations (1 g/100 ml) the total IgG and IgG subclass concentrations of the various IV and IM preparations were similar. All the test preparations (IV and IM) possessed similar opsonic activity for S. aureus and S. pyogenes. These findings demonstrate that, in respect of IgG content and protective biological activity, Intragam and Polygam, the locally manufactured IM and IV Ig preparations, respectively, compared extremely favourably with the corresponding imported products.

Relationship of sociotropy/autonomy and dependency/self-criticism to DSM-III-R personality disorders

Relationships between Beck's constructs of sociotropy/autonomy and Blatt's constructs of dependency/self-criticism and the Diagnostic and Statistical Manual of Mental Disorders (3rd ed., rev.; American Psychiatric Association, 1987) Axis II personality disorders were examined. Two measures of personality styles and a structured diagnostic interview for personality disorders were administered to 138 outpatients. Significant relationships were found between both sets of constructs and a number of personality disorders using both categorical and dimensional measures of Axis II psychopathology. These relationships were consistent with previous theory, supporting recent conceptualizations extending the range of psychopathology associated with these personality styles from depression to the personality disorders. However, the autonomy/self-criticism dimension was correlated with a broader range of personality disorder traits and diagnoses than anticipated.

Ethnic differences in stroke mortality between non-Hispanic whites, Hispanic whites, and blacks. The National Longitudinal Mortality Study

BACKGROUND AND PURPOSE

Although US blacks are known to have an excess stroke mortality compared with US whites, little is known about the stroke burden of the Hispanic white population. This report will provide estimates of the relative burden of stroke mortality in the US black and Hispanic population relative to the white population and examine the consistency of this relation across age.

METHODS

Data were from participants aged > 45 years from the National Longitudinal Mortality Study. There were 1844 stroke deaths among 239,734 non-Hispanic whites, 46 deaths among 12,527 Hispanic whites, and 234 deaths among 23,468 black participants. Standard statistical methods were used to examine the ethnic differences in stroke mortality.

RESULTS

The hazard ratios for black men and women (relative to non-Hispanic whites) were nearly identical, at > 4.0 at age 45 but marginally < 1.0 by age 85. For both Hispanic men and women, the hazard ratios (relative to non-Hispanic whites) were approximately 1.0 at age 45 but were marginally significantly < 1.0 at older ages. The ethnic differences in stroke death rates reveal differences in age distributions of age at fatal stroke between these groups. Approximately 6% of fatal strokes for non-Hispanic whites occurred before age 60, whereas > 15% occurred in both Hispanic whites and blacks.

CONCLUSIONS

These results suggest that (1) for Hispanics, stroke risk is similar to that for non-Hispanic whites at young ages but is marginally lower at older ages, (2) the excess stroke mortality in blacks mainly occurs at younger ages (between 45 and 55 years), and (3) the relation between stroke risk for blacks and Hispanics relative to whites is similar by sex. The impact of age on relative stroke mortality would argue against simple age adjustment for describing ethnic differences in stroke mortality. Finally, proportionally, more strokes occur at older ages in non-Hispanic whites than in either US blacks or Hispanic whites.

A comparison of calculated energy requirements to measured resting energy expenditure in HIV-1-infected subjects

Twenty HIV-infected outpatients participating in clinical drug trials of the National Institute of Allergy and Infectious Diseases (NIAID) and enrolled in the collaborative National Institute of Nursing Research (NINR) nutrition study underwent indirect calorimetry measurements. Energy requirements for these subjects also were calculated using the Harris Benedict Equation (HBE). In all 20 subjects, the calculated energy requirements underestimated actual resting expenditure as determined by indirect calorimetry.

Psychosocial interest, medical interviews, and the recognition of depression

OBJECTIVES

To measure primary care physicians' attitudes toward psychosocial issues, determine their relationship to the style of the medical interview, and assess whether attitudes and interview behaviors lead to correct diagnosis in patients with depression.

DESIGN

Physicians were videotaped while interviewing four patients standardized with criteria symptoms of major depression. Physicians were unaware of the mental health focus of the study.

SETTING

Patient examining rooms.

PARTICIPANTS

Physicians were eligible for recruitment if they were board certified or eligible in family practice or internal medicine, practiced primary care medicine, and were listed in regional directories. Standardized patients were recruited from the community.

MAIN OUTCOME MEASURES

Attitudes toward psychosocial issues (measured by the Physician Belief Scale), interview content (measured by review of the videotaped encounters), interview behaviors (measured by the Interaction Analysis System for Interview Evaluation), and a listing of depression in the differential diagnosis (determined by physician debriefing interviews).

RESULTS

Forty-seven community-based practitioners participated. Forty-eight percent of interviews resulted in a diagnosis of depression. Physician Belief Scale scores were not significantly correlated with patient-centered interviewing, psychosocial questions, inquiry about depression symptoms, or a depression diagnosis. Longer interviews were more likely to result in a depression diagnosis.

CONCLUSIONS

High interest in psychosocial issues was not associated with patient-centered interviewing behaviors, questions about psychosocial or depression symptoms, or depression diagnoses. However, certain patient-centered interviewing behaviors, particularly those defined as "affective," did lead to the recognition of depression.

Relationship between lung biopersistence and biological effects of man-made vitreous fibers after chronic inhalation in rats

This article describes the relationship between fiber biopersistence and the chronic toxicity of different chemical compositions of man-made vitreous fibers (MMVF) in the lung. Rats were exposed in "nose-only" inhalation chambers, 6 hr/day, 5 days/week, for 24 months to aerosol concentrations of 30 mg/m3 containing comparable fiber numbers and similar dimensions of fibrous glass (FG) or refractory ceramic fiber (RCF). Interim sacrifices were performed periodically to monitor fiber number and dimensions in the lung and the progression of pulmonary alterations. At each interim sacrifice, three to six recovery animals were removed from each exposure group and held until two years to determine the biopersistence of fibers after different exposure times. Fibers were recovered from the ashed lungs, counted, and measured using optical and scanning electron microscopy (SEM). Fiber chemistry was assessed in 91-week recovery lungs using energy dispersive spectroscopy (EDS) analysis. RCF induced lung fibrosis and an elevation in lung tumors and pleural mesotheliomas. FG exposure resulted in no lung fibrosis, no statistically significant increase in the lung tumor incidence, and no mesotheliomas. After two years of continuous exposure, the number of World Health Organization fibers per milligram dry lung recovered from RCF and FG exposed lungs was comparable. EDS analysis of recovery lungs showed that most of the alkalis and alkaline earths had leached from the FG fibers over time. A slight change in RCF chemistry was observed. These findings indicate that the change in the chemical composition of fibers may be an important determinant of the chronic toxicity of MMVFs.