Ambrisentan for sarcoidosis associated pulmonary hypertension.

BACKGROUND: Sarcoidosis associated pulmonary hypertension (SAPH) is associated with significant morbidity and mortality. There is a paucity of information concerning therapy for this condition. METHODS: We performed a prospective, open-label, proof of concept trial of ambrisentan for SAPH. 21 subjects with SAPH received 5 mg/day of ambrisentan for 4 weeks and then 10/mg day for 20 subsequent weeks. RESULTS: No significant change was noted in the 6-minute walk distance over the course of the study (mean change between week 0 and 24: 9.8 +/- 54.6 meters, p: NS). There were also no significant differences between weeks 0 and 24 in terms of dyspnea as measured by the modified Borg scale, serum brain naturetic peptide, diffusing capacity, and quality of life as measured by the Short Form-36. There was a high dropout rate: overall: 11/21, 52%; social reasons: 3/21, 14%; medical reasons: 8/21, 38% because of dyspnea: 6/21, 29% and/or edema: 4/21, 19%. Of those who completed the 24 week study (10/21, 48%), there was an improvement in their WHO functional class and a marked improvement in their health related quality of life as measured by the St. George Respiratory questionnaire (-15.3 +/- 25.0). However both these improvments did not reach statistical significance possibly because of the small sample size. CONCLUSION: Although ambrisentan was not well tolerated by many of these subjects with SAPH, in those who remained in this 24-week trial, improvements in WHO functional class and in health related quality of life suggested a possible benefit of this drug in selected patients.

Therapeutic failure in American cutaneous leishmaniasis is associated with gelatinase activity and cytokine expression.

Cutaneous lesions caused by Leishmania braziliensis infection occasionally heal spontaneously, but with antimonials therapy heal rapidly in approximately 3 weeks. However, about 15% of the cases require several courses of therapy. Matrix metalloproteinase-2 (MMP-2) and MMP-9 are gelatinases that have been implicated in other chronic cutaneous diseases and skin re-epithelialization. These enzymes are controlled by their natural inhibitors [tissue inhibitors of metalloproteinase (TIMPs)] and by some cytokines. Uncontrolled gelatinase activity may result in intense tissue degradation and, consequently, poorly healing wounds. The present study correlates gelatinase activity to therapeutic failure of cutaneous leishmaniasis (CL) lesions. Our results demonstrate an association between gelatinase activity and increased numbers of cells making interferon (IFN)-γ, interleukin (IL)-10 and transforming growth factor (TGF)-ß in lesions from poor responders. Conversely, high levels of MMP-2 mRNA and enhanced MMP-2 : TIMP-2 ratios were associated with a satisfactory response to antimonials treatment. Additionally, high gelatinolytic activity was found in the wound beds, necrotic areas in the dermis and within some granulomatous infiltrates. These results indicate the importance of gelatinase activity in the skin lesions caused by CL. Thus, we hypothesize that the immune response profile may be responsible for the gelatinase activity pattern and may ultimately influence the persistence or cure of CL lesions.

Non-suppurative cellulitis: risk factors and its association with Staphylococcus aureus colonization in an area of endemic community-associated methicillin-resistant S. aureus infections.

Suppurative methicillin-resistant Staphylococcus aureus (MRSA) skin infections are common and associated with MRSA colonization, but little is known about non-suppurative cellulitis and its relationship with MRSA colonization in areas endemic for community-associated MRSA. We prospectively enrolled patients hospitalized for non-suppurative cellulitis (n=50) and matched controls (n=100) and found S. aureus colonization was similar in cases and controls (30% vs. 25%, P=0·95). MRSA was uncommon in cases (6%) and controls (3%) (P=0·39). All MRSA isolates were USA300 by pulsed-field gel electrophoresis. Independent risk factors for non-suppurative cellulitis were diabetes (OR 3·5, 95% CI 1·4-8·9, P=0·01) and homelessness in the previous year (OR 6·4, 95% CI 1·9-20·9, P=0·002). These findings suggest that MRSA may only rarely be causative of non-suppurative cellulitis.

Inhaled iloprost for sarcoidosis associated pulmonary hypertension.

RATIONALE: Patients with sarcoidosis associated pulmonary hypertension (SAPH) have responded to systemic prostacyclin therapy. OBJECTIVES: To determine the rate of response to inhaled prostacyclin, iloprost, in SAPH. METHODS: Sarcoidosis patients with pulmonary hypertension and no evidence for left ventricular dysfunction were enrolled in an open label, prospective study. Patients underwent right heart catheterization and six minute walk (6MW) test. Quality of life was evaluated using several instruments, including the Saint George Respiratory Questionnaire (SGRQ). Patients received 5 mcg of inhaled iloprost every 2-3 hours while awake. After four months of therapy, patients underwent repeat cardiac catheterization, 6 MW test, and completed quality of life questionnaires. MEASUREMENTS AND MAIN RESULTS: Of the 22 patients enrolled, 15 completed all 16 weeks of therapy. The most common reasons for study discontinuation included drug associated cough (3 patients) and compliance with the prescribed number of treatments per day (2 patients). Six patients experienced a 20% or greater decrease in pulmonary vascular resistance (PVR) from baseline with five of these six patients also showing > or = 5 mm Hg reduction in PA mean. Although three patients improved the 6MW distance by at least 30 meters, only one had a decrease in PVR. At 16 weeks a significant decrease was reported in the SGRQ activity score (p = 0.0273), with seven patients having a 4 point or greater decrease. CONCLUSION: Inhaled iloprost as monotherapy was associated with an improvement in pulmonary hemodynamics and quality of life as assessed by the SGRQ activity score in some sarcoidosis patients with SAPH.

Cutaneous signs of child abuse

Maltreatment of children is a major public health crisis, and it is estimated that each year more than 3 million children are victims of abuse. Safeguarding the welfare of children is a priority, and it is the moral and ethical responsibility of healthcare professionals to detect cases of abuse and intervene appropriately to prevent further harm. Clinicians are often challenged to differentiate signs of child abuse from skin conditions that mimic maltreatment. Because cutaneous injury represents the most recognizable and common form of abuse, dermatologists are often called upon to help distinguish signs of intentional injury from skin conditions that mimic maltreatment. However, few resources specific to dermatologic signs of abuse exist to aid in diagnosis. A review of the literature will provide an educational resource to assist dermatologists and other clinicians in differentiating cutaneous signs of child abuse, including physical and sexual abuse, from mimickers of inflicted injury. LEARNING OBJECTIVE: After completing this learning activity, participants should be able to distinguish signs of intentional injury from skin conditions that mimic maltreatment and understand the clinician's role in the diagnosis and reporting of cases of suspected child abuse.

Carotenoid, tocopherol, and retinol concentrations in elderly human brain.

BACKGROUND: Antioxidants, such as tocopherols and carotenoids, have been implicated in the prevention of degenerative diseases. Although correlations have been made between diseases and tissue levels of antioxidants, to date there are no reports of individual carotenoid concentrations in human brain. OBJECTIVE: To measure the major carotenoids, tocopherols, and retinol in frontal and occipital regions of human brain. DESIGN: Ten samples of brain tissue from frontal lobe cortex and occipital cortex of five cadavers were examined. Sections were dissected into gray and white matter, extracted with organic solvents, and analyzed by HPLC. RESULTS: At least 16 carotenoids, 3 tocopherols, and retinol were present in human brain. Major carotenoids were identified as lutein, zeaxanthin, anhydrolutein, alpha- cryptoxanthin, beta- cryptoxanthin, alpha-carotene, cis- and trans-betacarotene, and cis- and trans-lycopene. Xanthophylls (oxygenated carotenoids) accounted for 66-77% of total carotenoids in all brain regions examined. Similar to neural retina, the ratio of zeaxanthin to lutein was high and these two xanthophylls were significantly correlated (p <0.0001). The tocopherol isomers occurred in the brain over a wider range of mean concentrations (0.11-17.9 nmol/g) than either retinol (87.8 - 163.3 pmol/g) or the identified carotenoids (1.8-23.0 pmol/g). CONCLUSIONS: The frontal cortex, generally vulnerable in Alzheimer's disease, had higher concentrations of all analytes than the occipital cortex which is generally unaffected. Moreover, frontal lobes, but not occipital lobes, exhibited an age-related decline in retinol, total tocopherols, total xanthophylls and total carotenoids. The importance of these differences and the role(s) of these antioxidants in the brain remain to be determined.

Plasma and lung macrophage responsiveness to carotenoid supplementation and ozone exposure in humans.

OBJECTIVE: To examine the effect of ozone exposure and vegetable juice supplementation on plasma and lung macrophage concentrations of carotenoids. DESIGN: A randomized trial. SETTING: Subjects were exposed to ambient air prior to antioxidant supplementation and to ozone after antioxidant supplementation or placebo. Exposures occurred while exercising intermittently in a controlled metabolic chamber at the Human Studies Division, US EPA. SUBJECTS: In all, 23 healthy subjects between ages of 18 and 35 y. INTERVENTIONS: Subjects consumed a low fruit and vegetable diet for 3 weeks. After the first week, subjects underwent a sham exposure to filtered air with exercise, followed by bronchoalveolar lavage (BAL). Subjects were randomly assigned into supplement (one can vegetable juice, vitamins C and E daily) or placebo (orange soda, placebo pill daily) groups for 2 weeks. After the 2-week intervention, subjects were exposed to 0.4 ppm (784 microg/m(3)) ozone for 2 h with exercise followed by BAL. Blood samples were drawn before, immediately after and 3 h postexposure on each exposure day. The concentrations of nine carotenoids were determined by HPLC in BAL macrophages and plasma samples. RESULTS: Plasma concentrations of all the carotenoids that were present in the vegetable juice (except cis-beta-carotene) increased significantly in the supplemented group. Lung macrophage alpha-carotene concentrations increased significantly, lycopene isomers increased slightly, and all other carotenoids decreased (nonsignificantly) in the supplementation group following the intervention. Ozone exposure resulted in decreases in several carotenoids in plasma of the placebo group, but not in the supplemented group. CONCLUSIONS: Lung macrophage concentrations of carotenoids can be manipulated by diet. Ozone is a potent environmental oxidant that appears to reduce plasma carotenoids in nonsupplemented individuals.

Navy Asbestos Medical Surveillance Program, 1995-1999: demographic characteristics and smoking status.

A descriptive study of the Navy Asbestos Medical Surveillance Program is presented from data provided by the Navy Environmental Health Center in Norfolk, Virginia, with an emphasis on demographic characteristics and smoking. Analysis of 79,598 physical examinations for the period 1995 to 1999 revealed that Navy and Marine Corps civil service employees constituted 90% and Navy active duty personnel constituted 9%. Most personnel reported "no current exposure, have prior exposure" to asbestos (Navy active duty, 77%; civil service employees, 61%). Current smoking rates per year decreased for Navy active duty (from 34.6% to 28.7%) and civil service workers (from 26.0% to 21.6%), both reductions being significant for trend. Logistic regression for current smoking showed higher rates for Navy active duty and those with "direct" asbestos exposure, whereas those 50 years or older and of Asian ethnicity had lower smoking rates. These findings provide programmatic insights for the Asbestos Medical Surveillance Program and suggest areas for further study.

Innovative approaches to vitamin A assessment.

The health and sight of millions of children are compromised each year as a consequence of vitamin A (VA) deficiency. Serum retinol is the most commonly used indicator of VA status. Unfortunately, its use is impractical for national surveys because it involves collection of venous blood, centrifugation and frozen storage before analysis. To make VA assessment more practical, we have developed approaches incorporating dried blood spots (DBS) or portable instrumentation. DBS have been used as a sample matrix to screen neonates for many biochemical compounds. Until recently, it was not thought that VA was stable in DBS. However, we demonstrated that the measure of DBS retinol correlates well with serum retinol in both healthy adults (r(2) = 0.88-0.90) and compromised populations (r(2) = 0.73-0.84). Compared with serum retinol, the sensitivity and specificity of detecting VA deficiency by DBS retinol range from 73 to 93% and from 90 to 100%, respectively. Although few data are available, retinol binding protein (RBP) can also be measured in DBS. RBP has been used as a surrogate marker for serum retinol. Correlations coefficients (r(2)) between serum RBP and serum retinol range from 0.4 to 0.8. In addition, work has been done to develop portable instrumentation to measure VA status in the field. A fluorometer has been optimized for VA fluorescence and is linear into the deficient range for the direct fluorimetric measurement of serum holo-RBP. Progress is being made to use the instrument to directly measure holo-RBP in a drop of whole blood.

Serum carotenoids and radiographic knee osteoarthritis: the Johnston County Osteoarthritis Project.

OBJECTIVE: Antioxidant intake has been associated with less progression of radiographic knee osteoarthritis (OA), but studies of carotenoid biomarkers and OA have not been done. We examined associations between serum concentrations of nine naturally occurring carotenoids and radiographic knee OA. DESIGN: The study design was matched case-control. Sera were analysed by high-performance liquid chromatography for nine carotenoids: lutein, zeaxanthin, alpha- and beta-cryptoxanthin, trans- and cis-lycopene, alpha-carotene, and trans- and cis-beta-carotene. Conditional logistic regression was used to estimate the association between tertiles of each carotenoid and radiographic knee OA, independent of body mass index, education, serum cholesterol, and the other carotenoids. SETTING: Johnston County, North Carolina, United States of America. SUBJECTS: Two-hundred cases with radiographic knee OA (Kellgren-Lawrence grades > or = 2) and 200 controls (Kellgren-Lawrence grade = 0) were randomly selected from the Johnston County Osteoarthritis Project, and were matched on age, gender and race. RESULTS: Participants with serum levels of lutein or beta-cryptoxanthin in the highest tertile were approximately 70% less likely to have knee OA than controls (odds ratio (OR) [95% confidence interval (CI)] = 0.28 [0.11, 0.73] and 0.36 [0.14, 0.95], respectively). Those in the highest tertile of trans-beta-carotene (OR = 6.40 [1.86, 22.1]) and zeaxanthin (OR = 3.06 [1.19, 7.85]) were more likely to have knee OA. CONCLUSIONS: While certain carotenoids may protect against knee OA, others may increase the odds of knee OA. Further study of carotenoids and knee OA are warranted before clinical recommendations about these substances and knee OA can be made.

Efficacy of a vitamin A-fortified wheat-flour bun on the vitamin A status of Filipino schoolchildren.

BACKGROUND: Wheat flour is a possible food vehicle for vitamin A fortification. OBJECTIVE: This study assessed the efficacy of consumption of a vitamin A-fortified wheat-flour bun (pandesal) on the vitamin A status of school-age children. DESIGN: This was a double-masked clinical trial conducted in 396 and 439 children aged 6-13 y attending 4 rural schools in the Philippines. The children were randomly assigned to a vitamin A-fortified (experimental) or nonfortified (control) group. A 60-g vitamin A-fortified pandesal (containing approximately 133 microg retinol equivalents) or a nonfortified pandesal was consumed by the children 5 d/wk for 30 wk. Vitamin A status, hemoglobin concentration, anthropometric status, morbidity, and dietary intake were assessed at baseline and 30 wk later. A modified relative dose response (MRDR) was assessed in a subsample of 20% of the children ( approximately 75/group) with the lowest initial serum retinol concentration at the 30-wk follow-up. RESULTS: Baseline serum retinol significantly modified the effect of the intervention. The fortified group, whose initial serum retinol concentrations were below the median, had a 0.07 +/- 0.03-micromol/L greater improvement in serum retinol at the 30-wk follow-up than did the control group (P: = 0.02). Improved vitamin A status was also evident in the MRDR subsample. End-of-study differences in the MRDR showed that vitamin A- fortified pandesal intake decreased the percentage of children with inadequate liver vitamin A stores by 50% (15.3% compared with 28.6%; P: = 0.05). CONCLUSIONS: Daily consumption of vitamin A-fortified pandesal significantly improved the vitamin A status of Filipino school-age children with marginal-to-low initial serum retinol concentrations.

Retinol concentrations in capillary dried blood spots from healthy volunteers: method validation.

BACKGROUND: Vitamin A deficiency (VAD) is a major public health problem in the developing world, leading to >3 million eye-related problems in preschool children. Nearly 250 million children have subclinical VAD, resulting in a 23% increase in childhood mortality. Difficulties in obtaining samples to assess VAD have hampered the detection, intervention, and surveillance of VAD. The use of dried blood spots (DBS) could ameliorate many problems of vitamin A assessment. OBJECTIVE: The objective of this study was to validate the use of retinol in DBS for vitamin A assessment by comparing it with venous and capillary serum retinol. DESIGN: Venous and capillary blood specimens were obtained simultaneously from 20 healthy adult volunteers. From each blood specimen, both DBS and liquid serum were prepared (a total of 80 samples). All specimens were maintained at -70 degrees C until HPLC analysis. RESULTS: The mean retinol concentrations in the 4 sample types were as follows: venous serum (2.02 +/- 0.42 micromol/L, or 58 +/- 12 microg/dL), capillary serum (2.06 +/- 0.42 micromol/L, or 59 +/- 12 microg/dL), venous DBS (2.06 +/- 0.49 micromol/L, or 59 +/- 14 microg/dL), and capillary DBS (2.09 +/- 0.45 micromol/L, or 60 +/- 13 microg/dL). Of the 6 possible 2-way combinations, the R(2) values ranged from 0.77 for capillary DBS versus venous DBS to 0.95 for venous serum versus capillary serum. CONCLUSIONS: DBS retinol measured by HPLC is comparable with serum retinol. Thus, it is possible to compare and combine blood retinol concentration data obtained from DBS with current and historic measurements in serum.

Retinol analysis in dried blood spots by HPLC.

There are many advantages to measuring vitamin A in dried blood spots (DBS) from a finger prick as compared to plasma collected by venipuncture. The advantages include easier collection, transport and storage; accessibility to younger and more remote populations; and decreased risk of disease transmission. We describe a method for the extraction of retinol from DBS for analysis by HPLC and initial comparison to plasma retinol. The effects of various buffers, detergents, antioxidants and chelators were evaluated to establish the most effective approach to elute the retinol: retinol binding protein (holo-RBP) complex from the blood collection cards. The process involves ultrasonic agitation to elute holo-RBP into a phosphate buffer containing an antioxidant and metal chelator. The holo-RBP complex was denatured by the addition of ethanol containing additional antioxidants permitting the extraction of free retinol into hexane. Following solvent evaporation, the extract was dissolved in methanol for HPLC analysis. The initial measured retinol levels in freshly collected DBS declined for 6-10 d whether stored at 25, 4 or -20 degrees C, but remained consistent thereafter (homeostatic). By incorporating a "recovery/volume adjustment" factor, measured retinol values in homeostatic DBS were adjusted to the equivalent of plasma retinol. For 17 normal adults, the correlation coefficient was 0.90 between plasma retinol and adjusted DBS retinol in samples that had been stored at -70 degrees C for < 9 mo. The use of this new sample matrix for vitamin A assessment will allow access to previously unavailable populations.

Evidence for clonal outgrowth of androgen-independent prostate cancer cells from androgen-dependent tumors through a two-step process.

Prostate cancers require androgen for growth but progress to an androgen-independent stage under the selective pressure of androgen ablation therapy. Here we describe a novel human prostate cancer xenograft (LAPC-9) propagated by serial passage in male severe combined immunodeficient mice that expresses prostate-specific antigen and wild-type androgen receptor. In response to castration, LAPC-9 cells undergo growth arrest and persist in a dormant, androgen-responsive state for at least 6 months. After prolonged periods of androgen deprivation, spontaneous androgen-independent outgrowths develop. Thus, prostate cancers progress to androgen independence through two distinct stages, initially escaping dependence on androgen for survival and, subsequently, for growth. Through the use of serial dilution and fluctuation analysis, we provide evidence that the latter stage of androgen independence results from clonal expansion of androgen-independent cells that are present at a frequency of about 1 per 10(5)-10(6) androgen-dependent cells. We conclude that prostate cancers contain heterogeneous mixtures of cells that vary in their dependence on androgen for growth and survival and that treatment with antiandrogen therapy provides selective pressure and alters the relative frequency of these cells, thereby leading to outgrowths of androgen-independent cancers.

Mitogen-activated protein kinase kinase kinase 1 activates androgen receptor-dependent transcription and apoptosis in prostate cancer.

Mitogen-activated protein (MAP) kinases phosphorylate the estrogen receptor and activate transcription from estrogen receptor-regulated genes. Here we examine potential interactions between the MAP kinase cascade and androgen receptor-mediated gene regulation. Specifically, we have studied the biological effects of mitogen-activated protein kinase kinase kinase 1 (MEKK1) expression in prostate cancer cells. Our findings demonstrate that expression of constitutively active MEKK1 induces apoptosis in androgen receptor-positive but not in androgen receptor-negative prostate cancer cells. Reconstitution of the androgen receptor signaling pathway in androgen receptor-negative prostate cancer cells restores MEKK1-induced apoptosis. MEKK1 also stimulates the transcriptional activity of the androgen receptor in the presence or absence of ligand, whereas a dominant negative mutant of MEKK1 impairs activation of the androgen receptor by androgen. These studies demonstrate an unanticipated link between MEKK1 and hormone receptor signaling and have implications for the molecular basis of hormone-independent prostate cancer growth.

A mechanism for hormone-independent prostate cancer through modulation of androgen receptor signaling by the HER-2/neu tyrosine kinase.

Prostate cancer progresses from a hormone-sensitive, androgen-dependent stage to a hormone-refractory, androgen-independent tumor. The androgen receptor pathway functions in these androgen-independent tumors despite anti-androgen therapy. In our LAPC-4 prostate cancer model, androgen-independent sublines expressed higher levels of the HER-2/neu receptor tyrosine kinase than their androgen-dependent counterparts. Forced overexpression of HER-2/neu in androgen-dependent prostate cancer cells allowed ligand-independent growth. HER-2/neu activated the androgen receptor pathway in the absence of ligand and synergized with low levels of androgen to 'superactivate' the pathway. By modulating the response to low doses of androgen, a tyrosine kinase receptor can restore androgen receptor function to prostate cancer cells, a finding directly related to the clinical progression of prostate cancer.

Accumulation and retention of micellar beta-carotene and lutein by Caco-2 human intestinal cells.

Despite the interest in the diverse roles of dietary carotenoids in human health, little is known about the transfer of these plant pigments from foods to micelles during digestion and their subsequent transfer across the intestinal epithelium. We conducted this study to characterize the intestinal uptake of micellarized carotenoids using monolayers of differentiated Caco-2 human intestinal cells. Crystalline beta-carotene (BC) and lutein (LUT), solubilized in mixed micelles for delivery to cells, were stable in a tissue culture environment for 20 hours. Cellular accumulation of micellar BC and LUT was proportional to the media content of carotenoids at /=18 micromol/L. There was no indication that high levels of BC in medium or within cells adversely affected micellar LUT accumulation. These data support the use of the Caco-2 human cell line as a model for studying the intestinal uptake, absorption, and possible interactions of dietary carotenoids.

Mechanistic concepts in androgen-dependence of prostate cancer.

Androgen blockade is the mainstay of therapy in the clinical management of advanced prostate cancer. Recent progress on two fronts--the development of newer xenograft and transgenic models and a greater understanding of nuclear receptor signaling--has provided new insight into mechanisms of androgen-dependence in prostate cancer. This review centers on the concept that perturbations in androgen receptor signaling are likely to occur early in prostate cancer and play a critical role in progression to end stage hormone-refractory disease.