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J Hubbard

Publications and source records attributed to J Hubbard.

At least 19 recordsLinked to original sources
PubMed2005

The microstructure of di-alkyl chain cationic/nonionic surfactant mixtures: observation of coexisting lamellar and micellar phases and depletion induced phase separation.

The evolution of the microstructure and composition occurring in the aqueous solutions of di-alkyl chain cationic/nonionic surfactant mixtures has been studied in detail using small angle neutron scattering, SANS. For all the systems studied we observe an evolution from a predominantly lamellar phase, for solutions rich in di-alkyl chain cationic surfactant, to mixed cationic/nonionic micelles, for solutions rich in the nonionic surfactant. At intermediate solution compositions there is a region of coexistence of lamellar and micellar phases, where the relative amounts change with solution composition. A number of different di-alkyl chain cationic surfactants, DHDAB, 2HT, DHTAC, DHTA methyl sulfate, and DISDA methyl sulfate, and nonionic surfactants, C12E12 and C12E23, are investigated. For these systems the differences in phase behavior is discussed, and for the mixture DHDAB/C12E12 a direct comparison with theoretical predictions of phase behavior is made. It is shown that the phase separation that can occur in these mixed systems is induced by a depletion force arising from the micellar component, and that the size and volume fraction of the micelles are critical factors.

Journal Article↗
PubMed2005

All radial scars/complex sclerosing lesions seen on breast screening mammograms should be excised.

AIM: To determine the incidence of pre-malignant and malignant conditions in radial scars identified from screening mammograms in women taking part in the UK NHS breast cancer screening programme. METHODS: All women in our screening population from 1988 to 2002 with a radiological diagnosis of radial scar or complex sclerosing lesion confirmed on subsequent histopathology were included in this study. Patients were investigated with fine needle aspiration cytology then localisation biopsy (n=46) or straight to localisation biopsy (n=78). Patients where divided into two groups, one with pure RS/CSL with no associated epithelial features and the second with associated ADH, DCIS or invasive cancer. RESULTS: One hundred and twenty-four lesions were confirmed histologically as radial scar or complex sclerosing lesions. The median age was 58 years. Of the 124 patients, 82 were pure RS/CSL. Forty-two had associated epithelial lesions, 22 patients had ADH and 20 patients had either in situ or invasive carcinoma. Where FNA was performed (n=46), mammograms had shown three lesions suspicious of cancer, which were not proven histologically. Mammograms picked up five malignancies out of the nine RS/CSL with associated cancers. Of these, FNA confirmed malignancy in only two patients. Where FNA was not done (n=78), mammogram had read five pure RS/CSL as cancers. It picked up only four cancers in RS lesions with DCIS/Ca out of 11. CONCLUSION: All screen-detected stellate lesions should be excised due to their association with pre-malignant and malignant conditions.

Breast Neoplasms↗
PubMed2003

Identification of patients with a non-recurrent inferior laryngeal nerve by duplex ultrasound of the brachiocephalic artery.

A non-recurrent inferior laryngeal nerve (NRILN) is a rare anomaly that may increase the risk of injury during thyroid surgery. A NRILN results from an embryologic developmental abnormality of the aortic arches, demonstrated by the absence of the brachiocephalic artery and the presence of an aberrant subclavian artery (arteria lusoria). In our experience 100% of 104 patients with a NRILN were shown to have these abnormalities. We postulated that duplex scanning of the brachiocephalic artery could identify patients at risk of a NRILN. Twelve patients with an operative diagnosis of a right NRILN and associated vascular abnormalities underwent postoperative duplex scanning of the brachiocephalic artery. The examination was performed using a 7.5 or 3.5 MHz transducer. The average duration of assessment was 5 min. The absence of the brachiocephalic artery and the direct origin of the right common carotid artery from the arch of the aorta were demonstrated in each patient. Duplex scanning is a simple noninvasive method of identifying patients with the arterial abnormalities responsible for a NRILN. This may be used in the preoperative assessment of selected patients.

Brachiocephalic Trunk↗
PubMed2003

[Video-assisted parathyroidectomy in the management of patients with primary hyperparathyroidism].

INTRODUCTION: In recent years, different minimally invasive techniques of parathyroidectomy have been described. We performed a retrospective study to evaluate the indications and results of video-assisted parathyroidectomy (Vap) in the management of our patients with primary hyperparathyroidism (PHPT). MATERIALS AND METHODS: During the last 5 years (1998-2002), we operated on 528 patients with PHPT. Vap was proposed for patients with sporadic PHPT, without associated goiter and without previous neck surgery, in whom a single adenoma was localized by means of sonography and/or sestamibi scanning. Vap was performed by lateral approach with insufflation for patients with adenoma located deeply in the neck and by gasless midline approach for patients with adenoma located anteriorly. A quick parathyroid (qPTH) assay was used during the surgical procedures. Calcemia, phosphoremia and PTH were systematically evaluated in patients on days 1 and 8, 1 month and 1 year after surgery. All patients underwent pre-operative and postoperative investigations of vocal cord movements. RESULTS: Among 528 patients with PHPT, 228 (43%) were not eligible for Vap: associated nodular goiter (99 cases), previous neck surgery (42 cases), suspicion of multiglandular disease (25 cases), lack of pre-operative localization (48 cases), and miscellaneous causes (14 cases). Vap was performed in 300 patients with sporadic PHPT: 282 lateral access, 17 midline access and 1 thoracoscopy. Median operative time was 50 min (20-130 min). Conversion to conventional parathyroidectomy was required in 42 patients (14%): missed adenomas (11 cases), difficulties of dissection (7 cases), multiglandular disease correctly predicted by qPTH (10 cases); qPTH assay false negative results (3 cases), sestamibi scan false positive results (10 cases) and 1 sonography false positive result. One patient presented definitive recurrent nerve palsy. One patient had a persistent PHPT and one other patient had a recurrent PHPT. CONCLUSION: Vap can be proposed for more than half of patients with PHPT. In our experience Vap and conventional parathyroidectomy are complementary. Immediate results of Vap are similar to those obtained with conventional parathyroidectomy but no conclusions can be drawn in terms of influence of Vap on the outcome of the patients operated for PHPT.

Adenoma↗
PubMed2003

[Spontaneous cervical haematoma due to extracapsular haemorrhage of a parathyroid adenoma: a report of 2 cases].

The usual clinical manifestations of a parathyroid adenoma are due, in most of the cases, to hypercalcemia. The development of a spontaneous cervical or cervicomediastinal haematoma is a rare form of presentation. In case of a spontaneous cervical haematoma associated with dysphagia: measurement of serum calcium, phosphate and parathyroid hormone allows the diagnosis of haematoma due to extracapsular haemorrhage from a parathyroid adenoma. We report herein 2 cases.

Adenoma↗
PubMed2002

[Lessons learned from 274 laparoscopic adrenalectomies].

AIMS: To define the role of minimally invasive video-assisted surgery in the surgical management of adrenal disease and discuss the respective indications of the trans and retroperitoneal video assisted approaches. MATERIALS AND METHODS: During the last 8 years (1994-2001), 330 adrenalectomies were performed in 305 patients: 274 (83%) laparoscopic approaches and 56 (17%) open approach. Open surgery was reserved for patients presenting with large or malignant tumours (29 cases), multiple and/or extraadrenal phaeochromocytomas (13 cases), previous intraabdominal intestinal surgery (10 cases), and in those requiring concomitant intraabdominal surgery (4 cases). Laparoscopic adrenalectomy was performed using the lateral transperitoneal approach for 89 Conn's syndrome, 67 Cushing's syndrome, 2 virilizing tumours, 51 phaeochromocytomas and 65 non secretory tumours greater than 4 cm in diameter. Nineteen patients underwent bilateral adrenalectomy. RESULTS: There were no deaths. Twenty patients (7.3%) had a complication. Eleven cases required open conversion (4%) because of difficulties with dissection (8 cases), preoperative suspicion of malignancy (2 cases), and one pneumothorax. The average size of tumours was 34 mm (7-110 mm). There were 18 malignant tumours (6.5%): 8 adrenocortical carcinomas, 1 leiomyosarcoma, and 9 metastases. All patients with hormonally secreting tumours were cured of their endocrinopathy. There was 1 death secondary to hepatic metastases in a patient with an adrenocortical carcinoma. CONCLUSION: Most adrenal tumours are suitable for video assisted excision. The only absolute contraindication is an invasive carcinoma requiring an extended excision. The lateral, transperitoneal approach is the most suitable for tumours greater than 5-6 cm in diameter. Both the transperitoneal or retroperitoneal approaches are suitable for smaller tumours depending on operator choice and experience. However in the presence of a large right lobe of liver or previous intraabdominal surgery the retroperitoneal approach may be preferable.

Adrenal Gland Diseases↗
PubMed1999

Sustained anabolic effects of long-term androgen administration in men with AIDS wasting.

Fifty-one human immunodeficiency virus-positive men with hypogonadism and wasting were randomized to receive testosterone enanthate, 300 mg i.m. every 3 weeks, or placebo for 6 months, followed by open-label testosterone administration for 6 months. Subjects initially randomized to placebo gained lean body mass (LBM) only after crossover to testosterone administration (mean change +/- standard error of the mean, -0.6 +/- 0.7 kg [months 0-6] vs. 1.9 +/- 0.7 kg [months 6-12]; P = .03). In contrast, subjects initially randomized to testosterone continued to gain LBM during open-label administration (2.0 +/- 0.7 kg [months 0-6] vs. 1.6 +/- 0.6 kg [months 6-12]; P = .62) and had gained more LBM at 1 year than did subjects receiving testosterone for only the final 6 months of the study (3.7 +/- 0.8 kg vs. 1.0 +/- 1.0 kg; P = .05). Testosterone administration results in sustained increases in LBM during 1 year of therapy in hypogonadal men with AIDS wasting.

Cross-Over Studies↗
PubMed1999

Etiological role of mycobacterium in Crohn's disease: An assessment of the literature.

A possible etiologic role for mycobacteria in Crohn's disease has been the subject of much investigation. This paper critically reviews the literature exploring 4 major areas: (1) attempts to culture mycobacteria from intestinal specimens; (2) indirect detection of organisms in intestinal specimens by techniques including immunohistochemistry, nucleic acid hybridization and polymerase chain reaction; (3) detection of serum antibodies to mycobacteria, and (4) results of antimycobacterial drug trials in treating patients with Crohn's disease. While the evidence does not support an etiologic role for mycobacteria in Crohn's disease, newer techniques may change this conclusion.

Anti-Bacterial Agents↗
PubMed1999

Impact of binge eating on metabolic and leptin dynamics in normal young women.

Well defined eating disorders such as anorexia nervosa and bulimia are associated with significant known health risks. Although binge eating behavior is increased in unsuccessfully dieting obese women, other health implications of this common eating pattern are unknown. We hypothesized that ingestion of an entire day's calories at one time in the evening, a common eating practice among Americans, would lead to disruptions in glucose, insulin, and leptin metabolism and in menstrual cyclicity, even in healthy young women. Seven lean women without a history of eating disorders were studied on two occasions separated by one or two menstrual cycles. During one admission, they ate three regular meals plus a snack on each of 3 days. On the other admission, they ate the same number of calories, macronutrient matched to the normal diet, in a single evening meal. Glucose, insulin, and leptin were measured frequently for 12-14 h beginning at 0800 h on the third day of each diet, and an insulin tolerance test was performed while the subjects were fasting on the fourth day. Daily blood samples were obtained until ovulation was documented to assess any impact on menstrual function. Ingestion of an entire day's calories at dinner resulted in a significant increase in fasting glucose levels and a dramatic increase in insulin responses to the evening meal. The diurnal pattern of leptin secretion was altered, such that the gradual rise in leptin from 0800 h observed during the normal diet was abolished, and leptin did not begin to rise during the binge diet until at least 2 h after the evening meal. No changes were demonstrated in insulin sensitivity, follicular growth, or ovulation between the two diets. We conclude that 1) ingestion of a large number of calories at one time (binge eating) impacts metabolic parameters even when total calories and macronutrients are appropriate for weight; 2) the timing of energy intake is an independent determinant of the diurnal rhythm of leptin secretion, indicating a relatively acute affect of energy balance on leptin dynamics; 3) the mechanism of exaggerated insulin secretion after a binge meal remains to be determined, but may be related to the altered diurnal pattern of leptin secretion; and 4) as most binge eating episodes in the population are associated with the ingestion of excess calories, it is hypothesized that binge eating behavior is associated with even greater metabolic dysfunction than that described herein.

Adult↗
PubMed1998

Structural and dynamical characterization of a biologically active unfolded fibronectin-binding protein from Staphylococcus aureus.

A 130-residue fragment (D1-D4) taken from a fibronectin-binding protein of Staphylococcus aureus, which contains four fibronectin-binding repeats and is unfolded but biologically active at neutral pH, has been studied extensively by NMR spectroscopy. Using heteronuclear multidimensional techniques, the conformational properties of D1-D4 have been defined at both a global and a local level. Diffusion studies give an average effective radius of 26.2 +/- 0.1 A, approximately 75% larger than that expected for a globular protein of this size. Analysis of chemical shift, 3JHNalpha coupling constant, and NOE data show that the experimental parameters agree well overall with values measured in short model peptides and with predictions from a statistical model for a random coil. Sequences where specific features give deviations from these predictions for a random coil have however been identified. These arise from clustering of hydrophobic side chains and electrostatic interactions between charged groups. 15N relaxation studies demonstrate that local fluctuations of the chain are the dominant motional process that gives rise to relaxation of the 15N nuclei, with a persistence length of approximately 7-10 residues for the segmental motion. The consequences of the structural and dynamical properties of this unfolded protein for its biological role of binding to fibronectin have been considered. It is found that the regions of the sequence involved in binding have a high propensity for populating extended conformations, a feature that would allow a number of both charged and hydrophobic groups to be presented to fibronectin for highly specific binding.

Adhesins, Bacterial↗
PubMed1998

Determinants of increased energy expenditure in HIV-infected women.

BACKGROUND: Little is known about sex-specific effects of HIV infection on energy expenditure. OBJECTIVE: We investigated the determinants of energy expenditure in HIV-infected women. DESIGN: Resting energy expenditure (REE), body composition, and hormonal and nutritional indexes were compared in 33 ambulatory, premenopausal HIV-infected women and 26 weight-matched, healthy premenopausal control subjects. REE was determined by indirect calorimetry and body composition by dual-energy X-ray absorptiometry (DXA), bioelectrical impedance analysis, and skinfold-thickness analysis. Hormonal indexes included leptin, testosterone, estradiol, and insulin-like growth factor I. RESULTS: HIV-infected subjects had a higher REE than control subjects [6794 +/- 1374 compared with 6011 +/- 607 kJ/d (1624 +/- 329 compared with 1437 +/- 145 kcal/d), P = 0.0096]. On average, REE was 119 +/- 23% of Harris-Benedict predictions in HIV-infected subjects compared with 102 +/- 9% for control subjects (P = 0.0007). In HIV-infected subjects, REE was highly correlated with fat-free mass (FFM) by DXA (R = 0.641, P < 0.001), but not with weight or disease status. The slope of the regression equation for REE and FFM was significantly greater (P = 0.027, analysis of covariance) for HIV-infected subjects [REE (kJ/d) = 203.5 (kg FFM) - 1237] than for control subjects [REE (kJ/d) = 77.4 (kg FFM) + 2923]. In a stepwise regression analysis, FFM was the most significant variable (P = 0.005), followed by free testosterone (P = 0.029), which together explained 49% of the variation in REE. The final equation was REE (kJ/d) = 230.8 (kg FFM) + 395.9 (free testosterone, pmol/L) - 3304. CONCLUSIONS: Energy expenditure was higher in HIV-infected women than in control women. FFM is the primary determinant of REE in HIV-infected women, but energy expenditure is greater per kg FFM in HIV-infected subjects than in control subjects, which may contribute to the wasting syndrome.

Absorptiometry, Photon↗
PubMed1998

Decreased leptin levels in normal weight women with hypothalamic amenorrhea: the effects of body composition and nutritional intake.

Leptin is a protein encoded by the ob gene and expressed in adipocytes. A sensitive marker of nutritional status, leptin is known to correlate with fat mass and to respond to changes in caloric intake. Leptin may also be an important mediator of reproductive function, as suggested by the effects of leptin infusions to restore ovulatory function in an animal model of starvation. We hypothesized that leptin levels are decreased in women with hypothalamic amenorrhea and that leptin may be a sensitive marker of overall nutritional status in this population. We, therefore, measured leptin levels and caloric intake in 21 women with hypothalamic amenorrhea (HA) and 30 age-, weight-, and body fat-matched eumenorrheic controls. Age (24 +/- 5 vs. 24 +/- 3 yr), body mass index (20.6 +/- 1.3 vs. 21.1 +/- 1.5 kg/m2), percent ideal body weight (94.9 +/- 5% vs. 96.3 +/- 6.3%), and fat mass (14.2 +/- 3.6 vs. 15.5 +/- 2.9 kg, determined by dual energy x-ray absortiometry) did not differ between the groups. Leptin levels were significantly lower in the HA subjects compared with those in the controls (7.1 +/- 3.0 vs. 10.6 +/- 4.9 micrograms/L; P = 0.005). Total caloric intake (1768 +/- 335 vs. 2215 +/- 571 cal/day; P = 0.003), fat intake (333 +/- 144 vs. 639 +/- 261 cal/day; P < 0.0001), and insulin levels (5.6 +/- 1.2 vs. 7.4 +/- 3.2 microU/mL; P = 0.015) were lower in the women with HA than in the eumenorrheic controls. The difference in leptin levels remained significant after controlling for insulin (P = 0.023). These data are the first to demonstrate hypoleptinemia, independent of fat mass, in women with HA. The hypoleptinemia may reflect inadequate calorie intake, fat intake, and/or other subclinical nutritional disturbances in women with HA. The mechanism and reproductive consequences of low leptin in this large population of women remain unknown.

Adult↗
PubMed1997

NMR analysis of main-chain conformational preferences in an unfolded fibronectin-binding protein.

A 130-residue fragment of the Staphylococcus aureus fibronectin-binding protein has been found to exist in a highly unfolded conformation at neutral pH. Measurement of experimental NMR 3JHNalpha coupling constants provides evidence for individual residues having distinct main-chain conformational preferences that are dependent both on the amino acid concerned and on neighbouring residues in the sequence. Analysis shows that these variations in the populations of individual residues can be explained in detail in terms of statistical distributions of conformational states derived from the protein data base. In particular, when the preceding residue has a beta-branched or aromatic side-chain, a significant increase occurs in the population of the less sterically restricted b region of phi,psi space. The results indicate that the local structure of the fibronectin binding protein in solution, under conditions where it displays full activity, approximates very closely to a statistical random coil structure. This may be an important feature in the biological role of this and other polypeptides involved in protein-protein interactions.

Adhesins, Bacterial↗
PubMed1997

Effects of fasting and glucose infusion on basal and overnight leptin concentrations in normal-weight women.

The plasma concentration of leptin is reduced in association with chronic energy restriction and weight loss in humans, but little is known about the acute effects of fasting and glucose infusion on leptin. In this study, plasma leptin, insulin, glucose, and fatty acid concentrations were measured daily in 14 healthy, normal-weight, female volunteers aged 24 +/- 4 y with a body mass index (kg/m2) of 24.2 +/- 3.6 during a 4-d fast. The mean plasma leptin concentration decreased by 54 +/- 8% with fasting (P = 0.0006, ANOVA). In a stepwise-regression model, the change in leptin concentration with fasting correlated most significantly with the change in insulin (R2 = 0.48, P = 0.0057) and to a lesser extent with the change in body fat by bioimpedance analysis (R2 = 0.19, P = 0.03). Plasma leptin concentrations measured every 20 min from 2000 to 0800 on the fourth night of the fast did not show a time-dependent rise. A continuous intravenous infusion of 5% glucose providing 1414 +/- 323 kJ/d (338 +/- 78 kcal/d) was begun after 4 d of fasting in seven subjects who continued to fast for an additional 6 d. Within 24 h of the glucose infusion, leptin concentrations increased significantly by 80 +/- 52% (P < 0.05). These data show the sensitivity of plasma leptin concentrations to small changes in energy supply and suggest a basic role of substrate metabolism in the short-term regulation of leptin.

Adult↗
PubMed1997

Microdosimetry spectra of the Loma Linda proton beam and relative biological effectiveness comparisons.

Protons have long been recognized as low LET radiation in radiotherapy. However, a detailed account of LET (linear energy transfer) and RBE (relative biological effectiveness) changes with incident beam energy and depth in tissue is still unresolved. This issue is particularly important for treatment planning, where the physical dose prescription is calculated from a RBE using cobalt as the reference radiation. Any significant RBE changes with energy or depth will be important to incorporate in treatment planning. In this paper we present microdosimetry spectra for the proton beam at various energies and depths and compare the results to cell survival studies performed at Loma Linda. An empirically determined biological weighting function that depends on lineal energy is used to correlate the microdosimetry spectra with cell survival data. We conclude that the variations in measured RBE with beam energy and depth are small until the distal edge of the beam is reached. On the distal edge, protons achieve stopping powers as high as 100 keV/micron, which is reflected in the lineal energy spectra taken there. Lineal energy spectra 5 cm beyond the distal edge of the Bragg peak also show a high LET component but at a dose rate 600 times smaller than observed inside the proton field.

Animals↗
PubMed1997

Body composition and endocrine function in women with acquired immunodeficiency syndrome wasting.

The acquired immunodeficiency syndrome (AIDS) wasting syndrome is a devastating complication of human immunodeficiency virus (HIV) infection characterized by progressive weight loss and severe inanition. In men, the wasting syndrome is characterized by a disproportionate decrease in lean body mass and relative fat sparing. In contrast, relatively little is known about the gender-specific changes in body composition that characterize AIDS wasting in women. Three groups of women were studied to determine body composition and hormonal changes with respect to stage of wasting [nonwasting (NW; weight >90% ideal body weight; weight loss <10% of preillness maximum; n = 12), early wasting (EW; weight >90% ideal body weight; weight loss >10% of preillness maximum; n = 10), and late wasting (LW; weight <90%; n = 9)] and compared with a control group of 12, healthy, age-matched women. Weight loss averaged 6 +/- 6% (NW), 15 +/- 6% (EW), and 20 +/- 8% (LW) in the three groups. Lean, fat, and muscle masses were determined by dual energy x-ray absorptiometry and urinary creatinine excretion. Subjects were 36 +/- 5 yr of age (mean +/- SD) with a CD4 cell count of 379 +/- 239 cells/mm3. The body mass index was 24.4 +/- 2.6 kg/m2 (NW), 22.2 +/- 1.2 kg/m2 (EW), 18.2 +/- 2.0 kg/m2 (LW), and 24.3 +/- 2.6 kg/m2 (controls; P < 0.01, NW vs. EW; P < 0.0001, NW vs. LW). Lean body mass indexed for height was 15.7 +/- 2.4 kg/m2 (NW), 14.8 +/- 2.0 kg/m2 (EW), and 13.7 +/- 1.2 kg/m2 (LW) and was decreased significantly only in the LW group (P < 0.05 vs. NW). Muscle mass was 96% (NW), 94% (EW), and 78% (LW) of that predicted for height (P < 0.05, NW vs. LW). In contrast, fat mass indexed for height was decreased significantly among patients in both the EW and LW groups [8.7 +/- 1.9 kg/m2 (NW), 6.5 +/- 1.9 kg/m2 (EW), and 3.7 +/- 1.4 kg/m2 (LW); P < 0.05, NW vs. EW; P < 0.001, NW vs. LW). Expressed as a percentage of the value in nonwasting HIV-positive controls (NW), the relative loss of fat was greater than the loss of lean mass with progressive degrees of wasting [EW, 25% vs. 6% (fat vs. lean); LW, 58% vs. 13%]. The prevalence of amenorrhea was 20% among study subjects [17% (NW), 10% (EW), and 38% (LW)]. The percent predicted muscle mass was significantly lower in subjects with amenorrhea (74 +/- 8%) compared to that in eumenorrheic HIV-positive subjects (94 +/- 4%; P < 0.05). Estradiol levels were lower among subjects with amenorrhea (17.6 +/- 21.8 pg/mL) compared to eumenorrheic HIV-positive (48.9 +/- 33.6 pg/mL) and control (68.3 +/- 47.6 pg/mL) subjects and did not correlate with body composition. Mean free testosterone, but not total testosterone, levels were decreased in subjects with EW and LW compared to those in age-matched healthy controls, but not compared with those in NW [0.9 +/- 0.6 ng/dL (NW), 0.7 +/- 0.4 ng/dL (EW), 0.6 +/- 0.3 ng/dL (LW), and 2.0 +/- 2.4 ng/dL (controls); P < 0.05, EW vs. controls and LW vs. controls] and correlated with muscle mass (r = 0.37; P < 0.05). The percentages of women with free testosterone levels below the age-adjusted normal range were 33% (NW), 50% (EW), and 66% (LW). Dehydroepiandrosterone sulfate levels were also low in the subjects with LW compared to those in the control group [98 +/- 85 microg/dL (NW), 102 +/- 53 microg/dL (EW), 55 +/- 46 microg/dL (LW), and 132 +/- 68 microg/dL (controls); P < 0.05 LW vs. controls] and were correlated highly with free testosterone levels (r = 0.73; P < 0.00001) and also with muscle mass (r = 0.48; P < 0.01). These data demonstrate that women lose significant lean body and muscle mass in the late stages of wasting. However, in contrast to men, women exhibit a progressive and disproportionate decrease in body fat relative to lean body mass at all stages of wasting, consistent with gender-specific effects in body composition in AIDS wasting. (ABSTRACT TRUNCATED)

Absorptiometry, Photon↗