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1.
Dalton Trans ; 47(9): 3178-3184, 2018 Feb 27.
Article in English | MEDLINE | ID: mdl-29387857

ABSTRACT

A new system of highly ordered self-assembly intercalated polymer/clay nanocomposite is reported. These systems appear to be driven by entropic forces and are nanostructured but self-assemble across the micron scale. The systems exhibit extremely good gas barrier properties which do not fit the traditional tortuous path model of diffusion. In these complexes the intercalated system behaves differently than the bulk polymer. This behaviour can be explained by constrained polymer theory. The paper presents structural characteristics of the intercalates as well as gas barrier properties of films produced with the intercalated systems. A new radical approach to food packaging is proposed and demonstrated.

2.
Opt Lett ; 27(15): 1309-11, 2002 Aug 01.
Article in English | MEDLINE | ID: mdl-18026433

ABSTRACT

The spectroscopic properties of Ni(2+)- doped nanocrystalline glass-ceramic fibers are reported. The cerammed fibers show strong fluorescence with peak wavelength at 1250 nm, 3-dB bandwidth at ~250nm, measured lifetimes at >1ms, and low-fluorescence saturation powers (~35mW) for 980-nm diode pumping. Current diode-pumped output powers are ~100microW .

3.
Clin Infect Dis ; 33(7): 1060-8, 2001 Oct 01.
Article in English | MEDLINE | ID: mdl-11528581

ABSTRACT

To compare frequent measurement with infrequent measurement of human immunodeficiency virus (HIV) RNA levels in the management of antiretroviral therapy, we conducted a clinical strategy study of 206 HIV-infected patients who had <500 CD4 cells/mm(3). Patients were randomized (1.5:1) to undergo frequent monitoring (at baseline and every 2 months) or infrequent monitoring (at baseline and twice yearly), with CD4 cell counts determined every 2 months. Patients received unrestricted antiretroviral therapy. In the primary analysis (at month 6), the frequent group had a mean HIV RNA reduction (+/- standard deviation) of 0.93+/-0.79 log(10) copies/mL, versus 0.48+/-0.83 log(10) copies/mL for the infrequent group (P=.0002). A trend (P=.1) toward improved survival was seen in the frequent group. Given this improved virological response, more frequent HIV RNA measurement than is recommended in published guidelines (every 3-4 months) may be appropriate.


Subject(s)
Anti-HIV Agents/therapeutic use , HIV Infections/drug therapy , HIV-1/isolation & purification , RNA, Viral/blood , Adult , CD4 Lymphocyte Count , Female , HIV Infections/virology , HIV-1/physiology , Humans , Male , Middle Aged , Treatment Outcome
5.
Am J Infect Control ; 29(2): 79-84, 2001 Apr.
Article in English | MEDLINE | ID: mdl-11287873

ABSTRACT

BACKGROUND: Little information exists on risk factors for Pseudomonas aeruginosa infection in persons with HIV. We assessed the incidence and factors associated with P aeruginosa among persons with HIV enrolled in a large observational cohort study in Los Angeles. METHODS: Data were analyzed from 4825 persons aged > or =13 years with HIV infection enrolled from 4 outpatient facilities from 1990 to 1998. The association between P aeruginosa infection and demographic, risk behavior, and clinical factors was assessed. RESULTS: P aeruginosa was diagnosed in 72 (1.5%) patients representing a crude incidence rate of 0.74 per 100 person-years. The most frequent site of infection was pulmonary (47%). In multivariate analysis, prior hospitalization (adjusted rate ratio = 7.9, 95% CI, 3.8-16.2), and both dapsone (adjusted rate ratio = 4.0, 95% CI, 2.2-7.4) and trimethoprim-sulfamethoxazole (adjusted rate ratio = 2.5, 95% CI, 1.2-5.3) use were independently associated with higher rates of infection. Increasing days of inpatient stay (P <.01) and decreasing CD4(+) counts (P <.01) were strongly associated with P aeruginosa. Azithromycin use decreased the risk of infection by nearly 70%. CONCLUSION: Although the overall observed incidence of P aeruginosa was low, hospital exposure, declining CD4(+) levels, and the use of dapsone or trimethoprim-sulfamethoxazole increased the risk of P aeruginosa disease, and azithromycin use was protective in this population. These findings may assist in the early recognition and diagnosis of persons likely to be at increased risk of P aeruginosa infection.


Subject(s)
AIDS-Related Opportunistic Infections/epidemiology , AIDS-Related Opportunistic Infections/etiology , Cross Infection/epidemiology , Cross Infection/etiology , Hospitalization/statistics & numerical data , Pseudomonas Infections/epidemiology , Pseudomonas Infections/etiology , AIDS-Related Opportunistic Infections/prevention & control , AIDS-Related Opportunistic Infections/transmission , Adolescent , Adult , Anti-Bacterial Agents/adverse effects , Anti-Bacterial Agents/therapeutic use , Azithromycin/therapeutic use , CD4 Lymphocyte Count , Cohort Studies , Cross Infection/prevention & control , Cross Infection/transmission , Dapsone/adverse effects , Female , Health Behavior , Humans , Incidence , Infection Control , Length of Stay/statistics & numerical data , Los Angeles/epidemiology , Male , Middle Aged , Multivariate Analysis , Pseudomonas Infections/prevention & control , Pseudomonas Infections/transmission , Pseudomonas aeruginosa , Risk Factors , Risk-Taking , Trimethoprim, Sulfamethoxazole Drug Combination/adverse effects
6.
J Acquir Immune Defic Syndr ; 24(4): 386-92, 2000 Aug 01.
Article in English | MEDLINE | ID: mdl-11015156

ABSTRACT

OBJECTIVES: This paper describes research that examined the association between high-risk sexual and drug-using behaviors during incarceration and HIV infection for African-American men receiving HIV care at three public medical centers in Los Angeles County (LAC), California. METHODS: A case-control study was conducted in which 305 HIV-infected African-American men and 305 neighborhood controls, ages 20 to 49, were frequency-matched by age. RESULTS: After controlling for anal sex while not incarcerated, we found no association between anal sex during incarceration and HIV (odds ratio [OR], 1.1; 95% confidence interval [CI], 0.6-2.2). Among men with a history of incarceration (n = 332), the percentage reporting anal sex with men outside of incarceration (45%) was greater than those reporting anal sex while incarcerated (16%). Injection drug use (IDU) during incarceration was also not associated with HIV when controlling for IDU outside of incarceration (OR, 1.6; 95% CI, 0.5- 4.9). Increased time in jail or prison was associated with less HIV infection (p =.001). CONCLUSIONS: Although high-risk behaviors are more common in the community than in the incarcerated setting for this study group, incarcerated populations represent a high-risk group for whom access to prevention messages is limited. Periods of incarceration represent a unique opportunity to convey prevention messages that focus on high-risk behaviors outside the incarcerated setting.


Subject(s)
HIV Infections/psychology , Prisoners , Risk-Taking , Adult , Black or African American , Case-Control Studies , HIV Infections/complications , Homosexuality, Male , Humans , Los Angeles , Male , Middle Aged , Sexual Behavior , Substance Abuse, Intravenous/complications
7.
J Clin Endocrinol Metab ; 85(7): 2395-401, 2000 Jul.
Article in English | MEDLINE | ID: mdl-10902784

ABSTRACT

The clinical consequences of androgen deficiency in human immunodeficiency virus (HIV)-infected women remain underappreciated. The pharmacokinetics of transdermally administered testosterone in premenopausal women and HIV-infected women have not been studied. In this study we compared the pharmacokinetics of a novel testosterone matrix transdermal system (TMTDS) in healthy premenopausal women and women infected with HIV. Eight menstruating HIV-infected women, 18-50 yr of age, who had been receiving stable antiretroviral therapy, including a protease inhibitor, for at least 12 weeks and nine healthy, menstruating women of comparable age were enrolled. After baseline sampling during a 24-h control period in the early follicular phase (days 1-6), two TMTDS patches were applied with an expected delivery rate of 300 microg testosterone daily over an application period of 3-4 days. After 72 h, the patches were removed, a second set of two patches was applied, and blood samples were drawn over 96 h. Baseline serum total and free testosterone levels were lower in HIV-infected women than in healthy women. A diurnal rhythm of testosterone secretion, with higher levels in the morning and lower levels in the late afternoon, was apparent in both groups of women. Free testosterone levels were in the midnormal range at baseline in healthy women and increased above the upper limit of normal during TMTDS application. In HIV-infected women, free testosterone levels were in the low normal range at baseline and rose into the upper normal range during patch application. Serum total testosterone levels increased into the midnormal range in HIV-infected women and into the upper normal range in healthy women during patch application. The mean increments in free and total testosterone levels were significantly lower in HIV-infected women than in healthy women. Testosterone bioavailability, expressed as the mean +/- SEM baseline-subtracted area under the total testosterone curve, was significantly greater in healthy women than in HIV-infected women [3323 +/- 566 ng/dL x h (115 +/- 20 nmol/L x h) vs. 1506 +/- 316 ng/dL x h (52 +/- 11 nmol/ L x h); P = 0.016]. Assuming a daily testosterone delivery rate of 300 microg/day, the apparent plasma clearance was significantly higher in HIV-infected women than in healthy women (2531 +/- 469 vs. 1127 +/- 217 L/day1 P = 0.022), respectively. There was no significant change from baseline in serum LH, sex hormone-binding globulin, and estradiol levels in either group. Serum FSH levels showed a greater decrease from baseline in healthy women. A regimen of two testosterone patches applied twice a week can maintain serum total and free testosterone levels in the mid- to upper normal range, respectively, in HIV-infected women with low testosterone levels. During TMTDS application, the increments in serum total and free testosterone levels are lower in HIV-infected women than in healthy women, presumably due to increased plasma clearance or decreased absorption. Further studies are needed to assess the effects of physiological androgen replacement in HIV-infected women.


Subject(s)
HIV Infections/metabolism , Testosterone/pharmacokinetics , Administration, Cutaneous , Adolescent , Adult , Biological Availability , Circadian Rhythm/physiology , Female , Hormones/blood , Humans , Middle Aged , Testosterone/administration & dosage , Testosterone/adverse effects
8.
JAMA ; 283(6): 763-70, 2000 Feb 09.
Article in English | MEDLINE | ID: mdl-10683055

ABSTRACT

CONTEXT: Previous studies of testosterone supplementation in HIV-infected men failed to demonstrate improvement in muscle strength. The effects of resistance exercise combined with testosterone supplementation in HIV-infected men are unknown. OBJECTIVE: To determine the effects of testosterone replacement with and without resistance exercise on muscle strength and body composition in HIV-infected men with low testosterone levels and weight loss. DESIGN AND SETTING: Placebo-controlled, double-blind, randomized clinical trial conducted from September 1995 to July 1998 at a general clinical research center. PARTICIPANTS: Sixty-one HIV-infected men aged 18 to 50 years with serum testosterone levels of less than 12.1 nmol/L (349 ng/dL) and weight loss of 5% or more in the previous 6 months, 49 of whom completed the study. INTERVENTIONS: Participants were randomly assigned to 1 of 4 groups: placebo, no exercise (n = 14); testosterone enanthate (100 mg/wk intramuscularly), no exercise (n = 17); placebo and exercise (n = 15); or testosterone and exercise (n = 15). Treatment duration was 16 weeks. MAIN OUTCOME MEASURES: Changes in muscle strength, body weight, thigh muscle volume, and lean body mass compared among the 4 treatment groups. RESULTS: Body weight increased significantly by 2.6 kg (P<.001) in men receiving testosterone alone and by 2.2 kg (P = .02) in men who exercised alone but did not change in men receiving placebo alone (-0.5 kg; P = .55) or testosterone and exercise (0.7 kg; P = .08). Men treated with testosterone alone, exercise alone, or both experienced significant increases in maximum voluntary muscle strength in leg press (range, 22%-30%), leg curls (range, 18%-36%), bench press (range, 19%-33%), and latissimus pulls (range, 17%-33%). Gains in strength in all exercise categories were greater in men assigned to the testosterone-exercise group or to the exercise-alone group than in those assigned to the placebo-alone group. There was a greater increase in thigh muscle volume in men receiving testosterone alone (mean change, 40 cm3; P<.001 vs zero change) or exercise alone (62 cm3; P = .003) than in men receiving placebo alone (5 cm3; P = .70). Average lean body mass increased by 2.3 kg (P = .004) and 2.6 kg (P<.001), respectively, in men who received testosterone alone or testosterone and exercise but did not change in men receiving placebo alone (0.9 kg; P = .21). Hemoglobin levels increased in men receiving testosterone but not in those receiving placebo. CONCLUSION: Our data suggest that testosterone and resistance exercise promote gains in body weight, muscle mass, muscle strength, and lean body mass in HIV-infected men with weight loss and low testosterone levels. Testosterone and exercise together did not produce greater gains than either intervention alone.


Subject(s)
Exercise/physiology , HIV Infections/physiopathology , Muscle, Skeletal/physiology , Testosterone/metabolism , Testosterone/pharmacology , Weight Loss/physiology , Adult , Body Composition , Double-Blind Method , HIV Infections/metabolism , Humans , Male , Middle Aged , Sickness Impact Profile , Testosterone/administration & dosage , Thigh
9.
JAMA ; 282(24): 2305-12, 1999.
Article in English | MEDLINE | ID: mdl-10612317

ABSTRACT

CONTEXT: Adefovir dipivoxil is a nucleotide analog that has demonstrated effective antiretroviral activity against human immunodeficiency virus (HIV) with once-daily administration. OBJECTIVE: To determine if adefovir confers antiretroviral or immunologic benefit when added to stable antiretroviral therapy. DESIGN: Multicenter, 24-week, randomized, double-blind, placebo-controlled study. Enrollment was conducted from June 3, 1996, through May 6, 1997. SETTING: Thirty-three US HIV treatment centers. PARTICIPANTS: Of 1171 patients screened, 442 patients infected with HIV receiving stable antiretroviral therapy for at least 8 weeks with plasma HIV RNA greater than 2500 copies/mL and CD4+ cell count above 0.20 x 10(9)/L were randomized. INTERVENTION: Patients were randomized to receive either a single 120-mg/d dose of adefovir dipivoxil (n = 219) or an indistinguishable placebo (n = 223). All patients received L-carnitine, 500 mg/d. Open-label adefovir was offered after 24 weeks and was continued until the end of the study. MAIN OUTCOME MEASURES: Changes in HIV RNA from baseline, based on area under the curve and CD4+ cell levels, adverse events, and effect of baseline genotypic resistance on response to adefovir. RESULTS: Patients assigned to adefovir demonstrated a 0.4-log10 decline from baseline in HIV RNA compared with no change in the placebo group (P<.001), which continued through 48 weeks. CD4+ cell counts did not change. During the initial 24 weeks, elevated hepatic enzyme levels (P<.001), gastrointestinal tract complaints (P<.001), and weight loss (P<.001) were associated with use of adefovir. Between 24 weeks and 48 weeks elevations in serum creatinine occurred in 60% of patients, usually returning to baseline after discontinuation of adefovir. Patients with lamivudine or lamivudine and zidovudine resistance mutations demonstrated anti-HIV effects with adefovir (P< or =.01 vs placebo group). CONCLUSIONS: This study suggests that once-daily adefovir therapy reduces HIV RNA and is active against isolates resistant to lamivudine or lamivudine and zidovudine. Nephrotoxicity occurred when treatment extended beyond 24 weeks but was reversible.


Subject(s)
Adenine/analogs & derivatives , Anti-HIV Agents/therapeutic use , HIV Infections/drug therapy , Organophosphonates , Reverse Transcriptase Inhibitors/therapeutic use , Adenine/therapeutic use , Adult , Anti-HIV Agents/pharmacology , CD4 Lymphocyte Count , Double-Blind Method , Drug Resistance, Microbial , Drug Therapy, Combination , Female , Genotype , HIV Infections/immunology , HIV Infections/virology , HIV-1/drug effects , HIV-1/genetics , Humans , Lamivudine/pharmacology , Male , RNA, Viral , Viral Load , Zidovudine/pharmacology
10.
J Androl ; 20(5): 611-8, 1999.
Article in English | MEDLINE | ID: mdl-10520573

ABSTRACT

Weight loss is an important determinant of disease outcome in human immunodeficiency virus (HIV)-infected men. Others have suggested that a defect in dihydrotestosterone (DHT) generation contributes to weight loss in HIV-infected men. To determine whether DHT levels correlate with weight loss independently of changes in testosterone levels, we prospectively measured serum total- and free-testosterone and DHT levels in 148 consecutive HIV-infected men and 42 healthy men. Thirty-one percent of HIV-infected men had serum testosterone levels less than 275 ng/dL, the lower limit of the normal male range; of these, 81% had normal or low LH and FSH levels (hypogonadotropic), and 19% had elevated LH and FSH levels (hypergonadotropic). Overall, serum testosterone, free-testosterone, and DHT levels were lower in HIV-infected men than in healthy men, but serum DHT-to-testosterone ratios were not significantly different between the two groups. Serum total- and free-testosterone levels were lower in HIV-infected men who had lost 5 lb or more of weight in the preceding 12 months than in those who had not lost any weight. Serum DHT levels and DHT-to-testosterone ratios did not differ between those who had lost weight and those who had not. Serum testosterone and free-testosterone levels, but not DHT levels, correlated with weight change and with Karnofsky performance status. We also performed a retrospective analysis of data from a previous study in which HIV-infected men with serum testosterone levels less than 400 ng/dL had been treated with placebo or testosterone patches designed to nominally release 5 mg testosterone over 24 hours. Serum testosterone-to-DHT ratios did not change after testosterone treatment. Changes in fat-free mass were correlated with changes in both serum testosterone (r = 0.42, P = 0.018) and DHT (r = 0.35, P = 0.049) levels. Serum total- testosterone and DHT levels were highly correlated with one another, and when the change in serum testosterone was taken into account, serum DHT levels no longer showed a significant correlation with change in fat-free mass. We conclude that DHT levels are lower in HIV-infected men than in healthy men but that neither DHT levels nor DHT-to-testosterone ratios correlate with weight loss. During testosterone treatment, serum DHT levels increase proportionately, but the increments in serum testosterone correlate with the change in fat-free mass. Our data do not support the hypothesis that a defect in DHT generation contributes to weight loss in HIV-infected men independently of changes in testosterone levels; it is possible that such a defect might exist in HIV-infected men with more severe weight loss.


Subject(s)
Dihydrotestosterone/blood , HIV Infections/blood , Testosterone/blood , Weight Loss , Adolescent , Adult , Aged , Case-Control Studies , HIV Infections/physiopathology , Humans , Male , Middle Aged , Testosterone/administration & dosage
11.
AIDS ; 13(14): 1971-5, 1999 Oct 01.
Article in English | MEDLINE | ID: mdl-10513657

ABSTRACT

OBJECTIVE: To assess the factors that increase or decrease the risk of pneumonia with particular attention to immunization with pneumococcal and influenza vaccines in a group of HIV-infected persons. DESIGN: A retrospective, case-control study based on information entered into a standard database and the medical record. SETTING: Patients attending a referral clinic specializing in AIDS/HIV care at a public hospital. PATIENTS: Among over 2000 subjects entered into a database in 8 years, 127 incidents of pneumonia were identified from the record. These cases were matched with 127 CD4 cell count matched, concurrent controls. INTERVENTIONS: None. MAIN OUTCOME MEASURE: The principal hypothesis was that chart review would find a decreased frequency of pneumococcal immunization in the pneumonia cases compared with matched controls. RESULTS: Pneumococcal immunization was associated with a reduction of the risk of pneumonia by nearly 70%. The effect was seen even when immunization was given with a CD4 cell count of less than 100/mm3. Injection drug users and African-Americans had a twofold increased risk of pneumonia. CONCLUSION: The study provides data to support the current recommendation for pneumococcal immunization of all HIV-infected persons. Although this conclusion could lead to renewed enthusiasm for increasing pneumococcal immunization rates in HIV-infected persons, it must be recognized that the study is observational and ascertainment bias cannot be excluded.


Subject(s)
AIDS-Related Opportunistic Infections/prevention & control , Pneumonia, Pneumocystis/prevention & control , AIDS-Related Opportunistic Infections/epidemiology , AIDS-Related Opportunistic Infections/immunology , Adolescent , Adult , Case-Control Studies , Child , Child, Preschool , Databases, Factual , Female , Humans , Male , Middle Aged , Pneumonia, Pneumocystis/epidemiology , Pneumonia, Pneumocystis/immunology , Retrospective Studies , Risk Factors
12.
J Acquir Immune Defic Syndr ; 22(1): 39-48, 1999 Sep 01.
Article in English | MEDLINE | ID: mdl-10534145

ABSTRACT

The safety and antiretroviral effects of didanosine and stavudine in combination were evaluated in 86 people infected with HIV with CD4 counts between 200 and 500 cells/mm3 who had received <7 days of prior nucleoside analogue antiretroviral treatment. Patients were randomized to receive blinded treatments with one of five weight-adjusted, twice-daily regimens of didanosine and stavudine (100 + 10 mg, 100 + 20 mg, 100 + 40 mg, 200 + 20 mg, and 200 + 40 mg) for up to 1 year. Dosages were adjusted appropriately for patients weighing <60 kg and reduced in response to adverse effects. No clear dose-related differences among treatment groups were detected with regard to suppression of plasma HIV RNA level or reduction in infectious titers in peripheral blood mononuclear cells (PBMCs), improvement in CD4 count, or adverse effects. However, trends toward greater decreases in viral load and increases in CD4 count were detected when treatment groups containing the full recommended dosage of one or both agents (high-dose subgroup; arms 3, 4, and 5) were compared with the groups receiving lower dosages. At 28 weeks the mean log 10 HIV RNA decrease was 1.12 (n = 52) and at 52 weeks it was 0.97 (n = 32). Combination therapy was well tolerated, with no apparent dose-related adverse effects. Peripheral neuropathy occurred in 2 of 86 (2.3%) of patients. Didanosine and stavudine together appear to be a good nucleoside analogue foundation for aggressive triple- or quadruple-drug therapy. Full therapeutic doses of each of these two agents should be used to achieve optimal suppression of HIV replication.


Subject(s)
Anti-HIV Agents/therapeutic use , Didanosine/therapeutic use , HIV Infections/drug therapy , HIV/drug effects , Stavudine/therapeutic use , Adult , Aged , Anti-HIV Agents/adverse effects , Anti-HIV Agents/pharmacology , CD4 Lymphocyte Count , Didanosine/adverse effects , Didanosine/pharmacology , Dose-Response Relationship, Drug , Double-Blind Method , Drug Therapy, Combination , Female , HIV/genetics , HIV/physiology , HIV Infections/immunology , Humans , Male , Middle Aged , Peripheral Nervous System Diseases/chemically induced , RNA, Viral/blood , Stavudine/adverse effects , Stavudine/pharmacology , Viral Load , Virus Replication/drug effects , Weight Gain
13.
AIDS ; 13(9): 1099-107, 1999 Jun 18.
Article in English | MEDLINE | ID: mdl-10397541

ABSTRACT

OBJECTIVE: To correlate self-reported antiretroviral adherence with virologic suppression. DESIGN: Prospective observational study of adherence to therapy nested in a randomized comparative trial of frequent versus infrequent monitoring of plasma HIV RNA. SETTING: Five university-affiliated HIV clinics. PATIENTS: A group of 173 HIV-infected patients with a mean baseline CD4 count of 142 x 10(6) cells/l (range 3-515) of whom 164 and 119 completed adherence questionnaires at 2 and 6 months, respectively. INTERVENTION: Individualized, unrestricted antiretroviral therapy. MEASUREMENTS: Patients were classified into four groups by adherence to therapy in the previous 4 weeks (< 80%, 80-95%, 95-99%, 100%). Plasma HIV RNA levels and CD4 lymphocyte counts were measured bimonthly. RESULTS: Recreational drug or alcohol use was associated with decreased adherence, whereas frequency of HIV RNA monitoring, demographic variables, (age, gender, education, and risk group) and stage of disease had no effect. Greater HIV suppression at 6 months was seen across four categories of increasing adherence (P = 0.009 for linear trend). Patients reporting < 80% adherence at 6 months had a 0.2 log10 copies/ml increase in HIV RNA and a loss of 19 x 10(6) CD4 cells/l compared with a 1.1 log10 copies/ml decrease in HIV RNA and an increase of 72 x 10(6) CD4 cells/l in those reporting 100% adherence (P = 0.02). CONCLUSION: Self-reported poor adherence (< 80%) and drug or alcohol use predicted non-response of HIV RNA at 6 months of antiretroviral therapy.


Subject(s)
Anti-HIV Agents/therapeutic use , HIV Infections/drug therapy , HIV Infections/immunology , HIV-1/physiology , Patient Compliance , Adult , CD4 Lymphocyte Count , Female , Forecasting , HIV Infections/virology , Humans , Male , Middle Aged , Prospective Studies , RNA, Viral/blood , Treatment Outcome , Viral Load
14.
Epidemiol Infect ; 121(1): 197-204, 1998 Aug.
Article in English | MEDLINE | ID: mdl-9747773

ABSTRACT

The seasonality and factors associated with Cryptosporidium infection were assessed in a cohort of HIV-infected patients in Los Angeles County to better define the epidemiology of cryptosporidiosis among individuals with HIV. Data were analysed from a cohort of 4247 patients > or = 13 years of age with HIV infection enrolled from four outpatient facilities in Los Angeles, 1990-6. Cryptosporidiosis was diagnosed in 120 (2.8%) patients. Among the 1296 individuals with complete follow-up until death, cryptosporidiosis occurred in 69 (5.3%). The seasonal rate of cryptosporidiosis showed a modest bimodal trend with the highest rates occurring in March-May and September-October. There was no difference in the rate of cryptosporidiosis for the periods of heaviest rainfall (December-March) and low rainfall (April-November). Infection rates were higher among males (1.59 per 100 person-years) than females (0.92) and lower in blacks (0.98) than other racial/ethnic groups (1.80). A significant trend of decreasing cryptosporidiosis was observed with increasing age, with the highest rate (2.34) in the 13-34 year age group. A strong association between cryptosporidiosis and CD4+ count was noted. These data suggest that cryptosporidiosis among HIV-infected individuals in Los Angeles County exhibits a modest spring and fall seasonality. This pattern of occurrence of cryptosporidiosis appears temporally unrelated to local rainfall patterns. Our findings suggest that HIV-infected men, individuals in younger age groups and those with CD4+ lymphocyte counts < 100 x 10(6)/l are at increased risk of cryptosporidiosis. Blacks with HIV infection appear less likely than other racial/ethnic groups to be diagnosed with Cryptosporidium infection. These results may provide insight into possible routes of transmission and sources of cryptosporidiosis infection in individuals with HIV.


Subject(s)
Cryptosporidiosis/complications , Cryptosporidiosis/epidemiology , HIV Infections/complications , HIV Infections/epidemiology , Adolescent , Adult , Cohort Studies , Female , Humans , Los Angeles/epidemiology , Male , Middle Aged , Proportional Hazards Models , Risk Factors , Seasons , Survival Analysis
15.
J Clin Endocrinol Metab ; 83(9): 3155-62, 1998 Sep.
Article in English | MEDLINE | ID: mdl-9745419

ABSTRACT

Although weight loss associated with human immunodeficiency virus (HIV) infection is multifactorial in its pathogenesis, it has been speculated that hypogonadism, a common occurrence in HIV disease, contributes to depletion of lean tissue and muscle dysfunction. We, therefore, examined the effects of testosterone replacement by means of Androderm, a permeation-enhanced, nongenital transdermal system, on lean body mass, body weight, muscle strength, health-related quality of life, and HIV-disease markers. We randomly assigned 41 HIV-infected, ambulatory men, 18-60 yr of age, with serum testosterone levels below 400 ng/dL, to 1 of 2 treatment groups: group I, two placebo patches (n = 21); or group II, two testosterone patches designed to release 5 mg testosterone over 24 h. Eighteen men in the placebo group and 14 men in the testosterone group completed the 12-week treatment. Serum total and free testosterone and dihydrotestosterone levels increased, and LH and FSH levels decreased in the testosterone-treated, but not in the placebo-treated, men. Lean body mass and fat-free mass, measured by dual energy x-ray absorptiometry, increased significantly in men receiving testosterone patches [change in lean body mass, +1.345 +/- 0.533 kg (P = 0.02 compared to no change); change in fat-free mass, +1.364 +/- 0.525 kg (P = 0.02 compared to no change)], but did not change in the placebo group [change in lean body mass, 0.189 +/- 0.470 kg (P = NS compared to no change); change in fat-free mass, 0.186 +/- 0.470 kg (P = NS compared to no change)]. However, there was no significant difference between the 2 treatment groups in the change in lean body mass. The change in lean body mass during treatment was moderately correlated with the increment in serum testosterone levels (r = 0.41; P = 0.02). The testosterone-treated men experienced a greater decrease in fat mass than those receiving placebo patches (P = 0.04). There was no significant change in body weight in either treatment group. Changes in overall quality of life scores did not correlate with testosterone treatment; however, in the subcategory of role limitation due to emotional problems, the men in the testosterone group improved an average of 43 points of a 0-100 possible score, whereas those in the placebo group did not change. Red cell count increased in the testosterone group (change in red cell count, +0.1 +/- 0.1 10(12)/L) but decreased in the placebo group (change in red cell count, -0.2 +/- 0.1 10(12)/L). CD4+ and CD8+ T cell counts and plasma HIV copy number did not significantly change during treatment. Serum prostate-specific antigen and plasma lipid levels did not change in either treatment group. Testosterone replacement in HIV-infected men with low testosterone levels is safe and is associated with a 1.35-kg gain in lean body mass, a significantly greater reduction in fat mass than that achieved with placebo treatment, an increased red cell count, and an improvement in role limitation due to emotional problems. Further studies are needed to assess whether testosterone supplementation can produce clinically meaningful changes in muscle function and disease outcome in HIV-infected men.


Subject(s)
HIV Infections/complications , Testosterone/deficiency , Testosterone/therapeutic use , Absorptiometry, Photon , Adipose Tissue , Administration, Cutaneous , Adolescent , Adult , Body Composition , Dihydrotestosterone/blood , Double-Blind Method , Emotions , Follicle Stimulating Hormone/blood , HIV Infections/psychology , Humans , Luteinizing Hormone/blood , Male , Middle Aged , Placebos , Testosterone/adverse effects , Weight Loss
16.
J Clin Endocrinol Metab ; 83(4): 1312-8, 1998 Apr.
Article in English | MEDLINE | ID: mdl-9543161

ABSTRACT

Measurements of total and free testosterone levels in women have lacked precision and accuracy because of limited assay sensitivity. The paucity of normative data on total and free testosterone levels in healthy women has confounded interpretation of androgen levels in women with human immunodeficiency virus (HIV) infection and other disease states. Therefore, the objectives of this study were to develop sensitive assays for the measurement of the low total and free testosterone levels in women to define the range for these hormones during the normal menstrual cycle and assess the total and free testosterone levels in HIV-infected women. By using a larger volume of serum, increasing the incubation time, and reducing the antibody concentration, the sensitivity of the total testosterone assay was increased to 0.008 nmol/L, and that of the free testosterone assay was increased to 2 pmol/L. The mean percent free testosterone was 1.0 +/- 0.1% of the total testosterone. Serum total and free testosterone levels in the follicular and luteal phases were not significantly different, but both demonstrated a modest preovulatory increase, 3 days before the LH peak. Serum total [0.50 +/- 0.32 (14.60 +/- 9.22) vs. 1.2 +/- 0.7 nmol/L (34.3 +/- 21.0 ng/dL); P < 0.0001] and free testosterone levels (5.56 +/- 2.70 (1.58 +/- 0.80) vs. 12.8 +/- 5.5 pmol/L (3.4 +/- 1.7 pg/mL); P < 0.0001) were significantly lower in HIV-infected women (n = 37) than in healthy women (n = 34). Serum total and free testosterone levels were also significantly lower in HIV-infected women who were menstruating normally. There were no significant differences in serum total and free testosterone levels between those who had lost weight and those who had not. Testosterone levels correlated inversely with plasma HIV ribonucleic acid copy number. Serum FSH, but not LH, levels were significantly higher in HIV-infected women than in controls. Using assays with sufficient sensitivity, we defined the range for total and free testosterone levels during the normal menstrual cycle. Serum total and free testosterone levels are lower in HIV-infected women and correlate inversely with plasma HIV ribonucleic acid levels. The hypothesis that androgen deficiency contributes to wasting in HIV-infected women remains to be tested.


Subject(s)
HIV Infections/blood , Menstrual Cycle/physiology , Testosterone/blood , Adult , Analysis of Variance , Case-Control Studies , Dialysis , Female , Follicle Stimulating Hormone/blood , Humans , Luteinizing Hormone/blood , Middle Aged , Radioimmunoassay , Reference Values , Reproducibility of Results , Sensitivity and Specificity , Sex Hormone-Binding Globulin/metabolism
18.
AIDS ; 11(5): 673-9, 1997 Apr.
Article in English | MEDLINE | ID: mdl-9108950

ABSTRACT

OBJECTIVE: To determine the incidence and factors associated with extrapulmonary cryptococcosis among a cohort of persons with HIV in Los Angeles County. DESIGN: Records-based cohort study. METHODS: Data were analysed from a cohort of 3836 persons aged > or = 13 years with HIV infection enrolled from four outpatient facilities in Los Angeles from 1990 to 1995. The potential association between cryptococcosis and demographic risk behavior and clinical factors was assessed. Possible seasonal clustering was evaluated and an estimate of survival following cryptococcosis was calculated. Multivariate analysis was performed using a Cox proportional hazards approach. RESULTS: Cryptococcosis was identified in 112 patients (2.9%) representing a crude incidence rate of 1.7 cases per 100 person-years experience. The rate of cryptococcosis was higher among men than women (1.9 and 0.6, respectively; P < 0.01) and in Hispanics than in whites (2.3 and 1.2, respectively, P < 0.01). A significant trend of decreasing cryptococcosis was observed with increasing age (P < 0.01). Cryptococcosis increased with declining CD4+ lymphocyte count, with risk being greatest at CD4+ cell counts below 100 x 10(6)/l (P < 0.001). In bivariate analysis persons with a history of antifungal medication had a marginally lower rate of cryptococcosis, but this difference was not statistically significant. The rate of cryptococcosis was significantly higher in fall and winter months [rate ratio (RR), 1.45; 95% confidence interval (CI), 1.0-2.3; P = 0.05]. After controlling for other variables, cryptococcosis was more common in men than women (adjusted RR, 3.2; 95% CI, 1.0-10.4) and in Hispanics than whites (adjusted RR, 1.6; 95% CI, 0.9-2.7). Both CD4+ count and age continued to be strongly associated with the occurrence of cryptococcosis. After controlling for other factors a substantial protective effect was observed for antifungal therapy (adjusted RR, 0.48; 95% CI, 0.29-0.79). CONCLUSION: Our data suggest that HIV-infected men, Hispanics, persons aged under 45 years and those with CD4+ counts under 100 x 10(6)/l have an increased risk of extrapulmonary cryptococcosis. A fall-winter seasonality in the occurrence of cryptococcosis may exist. Significant primary protection against cryptococcal disease is afforded by antifungal therapy. These results may provide insight into possible routes of transmission and sources of cryptococcal infection and help guide both primary prophylaxis and early recognition and diagnosis in persons likely to be at increased risk.


Subject(s)
AIDS-Related Opportunistic Infections/epidemiology , Cryptococcosis/epidemiology , HIV Infections/complications , Adolescent , Adult , Cryptococcosis/etiology , Female , HIV Infections/epidemiology , Humans , Incidence , Los Angeles/epidemiology , Male , Middle Aged , Risk Factors
20.
Ann Allergy Asthma Immunol ; 78(2): 209-12, 1997 Feb.
Article in English | MEDLINE | ID: mdl-9048529

ABSTRACT

BACKGROUND: Gastrointestinal complaints and pruritic skin conditions are common in patients infected with human immunodeficiency virus (HIV). Because atopic disorders such as drug allergy, asthma, and allergic rhinitis are apparently increased, we hypothesized that food allergy may also be more common in patients with HIV. OBJECTIVE: The purpose of this study was to estimate the prevalence of food allergy in patients infected with HIV. METHODS: Consecutive patients visiting our outpatient adult HIV clinic were screened for possible food allergy by use of a questionnaire. One hundred seventy-six patients responded. Sixty-two of these patients reported symptoms compatible with a possible food allergy. Followup of the 62 subjects was possible in 40. Thirty-one patients were skin tested for foods thought to produce reactions. RESULTS: Three patients (1.7%) described previous anaphylactic responses to specific foods and were therefore not skin tested or challenged orally. Six patients (3.4%) described very strong histories of food allergy but either refused or were too ill for testing. Twenty-nine of the 31 patients had negative skin tests. One of the two patients with a positive skin test to a suspected food also had a positive double-blind, placebo-controlled food challenge (DBPCFC). There was no correlation between CD4 cell count and likelihood of food allergy. Based on a strong history alone, the maximal estimated prevalence of food allergy in this group was 5.7% (10 of 176). By using the more strict criterion of positive DBPCFC, the prevalence of food allergy in this patient population was 0.57% (1 of 176). CONCLUSION: These results suggest that food allergy is an uncommon disease in patients with HIV infection with an estimated prevalence similar to that found in the general adult population. Our data do not suggest an obvious direct correlation between HIV infection and food allergy.


Subject(s)
Food Hypersensitivity/diagnosis , HIV Infections/complications , Adult , Anaphylaxis , CD4 Lymphocyte Count , Female , Food Hypersensitivity/complications , Food Hypersensitivity/epidemiology , Humans , Male , Prevalence , Radioallergosorbent Test , Skin Tests/adverse effects , Surveys and Questionnaires
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