Showing papers by "University of Alabama at Birmingham published in 2003"
Boston University1, Rush University Medical Center2, University of Tennessee Health Science Center3, University of Michigan4, University at Buffalo5, University of Mississippi6, University of Miami7, University of Alabama at Birmingham8, Case Western Reserve University9, National Institutes of Health10
TL;DR: The most effective therapy prescribed by the most careful clinician will control hypertension only if patients are motivated, and empathy builds trust and is a potent motivator.
Abstract: "The Seventh Report of the Joint National Committee on Prevention, Detection,
Evaluation, and Treatment of High Blood Pressure" provides a new guideline
for hypertension prevention and management. The following are the key messages(1) In persons older than 50 years, systolic blood pressure (BP) of
more than 140 mm Hg is a much more important cardiovascular disease
(CVD) risk factor than diastolic BP; (2) The risk of CVD, beginning at 115/75
mm Hg, doubles with each increment of 20/10 mm Hg; individuals who are normotensive
at 55 years of age have a 90% lifetime risk for developing hypertension; (3)
Individuals with a systolic BP of 120 to 139 mm Hg or a diastolic BP of 80
to 89 mm Hg should be considered as prehypertensive and require health-promoting
lifestyle modifications to prevent CVD; (4) Thiazide-type diuretics should
be used in drug treatment for most patients with uncomplicated hypertension,
either alone or combined with drugs from other classes. Certain high-risk
conditions are compelling indications for the initial use of other antihypertensive
drug classes (angiotensin-converting enzyme inhibitors, angiotensin-receptor
blockers, β-blockers, calcium channel blockers); (5) Most patients with
hypertension will require 2 or more antihypertensive medications to achieve
goal BP (<140/90 mm Hg, or <130/80 mm Hg for patients with diabetes
or chronic kidney disease); (6) If BP is more than 20/10 mm Hg above goal
BP, consideration should be given to initiating therapy with 2 agents, 1 of
which usually should be a thiazide-type diuretic; and (7) The most effective
therapy prescribed by the most careful clinician will control hypertension
only if patients are motivated. Motivation improves when patients have positive
experiences with and trust in the clinician. Empathy builds trust and is a
potent motivator. Finally, in presenting these guidelines, the committee recognizes
that the responsible physician's judgment remains paramount.
24,988 citations
TL;DR: The detection of autologous Nab as early as 52 days after detection of HIV-specific antibodies is reported, indicating a new mechanism contributing to HIV-1 persistence in the face of an evolving antibody repertoire.
Abstract: Neutralizing antibodies (Nab) are a principal component of an effective human immune response to many pathogens, yet their role in HIV-1 infection is unclear. To gain a better understanding of this role, we examined plasma from patients with acute HIV infection. Here we report the detection of autologous Nab as early as 52 days after detection of HIV-specific antibodies. The viral inhibitory activity of Nab resulted in complete replacement of neutralization-sensitive virus by successive populations of resistant virus. Escape virus contained mutations in the env gene that were unexpectedly sparse, did not map generally to known neutralization epitopes, and involved primarily changes in N-linked glycosylation. This pattern of escape, and the exceptional density of HIV-1 envelope glycosylation generally, led us to postulate an evolving 'glycan shield' mechanism of neutralization escape whereby selected changes in glycan packing prevent Nab binding but not receptor binding. Direct support for this model was obtained by mutational substitution showing that Nab-selected alterations in glycosylation conferred escape from both autologous antibody and epitope-specific monoclonal antibodies. The evolving glycan shield thus represents a new mechanism contributing to HIV-1 persistence in the face of an evolving antibody repertoire.
2,427 citations
TL;DR: The addition of adalimumab at a dosage of 20 mg, 40 mg, or 80 mg administered subcutaneously every other week to long-term MTX therapy in patients with active RA provided significant, rapid, and sustained improvement in disease activity over 24 weeks compared with MTX plus placebo.
Abstract: Objective
To evaluate the efficacy and safety of adalimumab (D2E7), a fully human monoclonal tumor necrosis factor α antibody, in combination with methotrexate (MTX) in patients with active rheumatoid arthritis (RA) despite treatment with MTX.
Methods
In a 24-week, randomized, double-blind, placebo-controlled study, 271 patients with active RA were randomly assigned to receive injections of adalimumab (20 mg, 40 mg, or 80 mg subcutaneously) or placebo every other week while continuing to take their long-term stable dosage of MTX. The primary efficacy end point was the American College of Rheumatology criteria for 20% improvement (ACR20) at 24 weeks.
Results
An ACR20 response at week 24 was achieved by a significantly greater proportion of patients in the 20-mg, 40-mg, and 80-mg adalimumab plus MTX groups (47.8%, 67.2%, and 65.8%, respectively) than in the placebo plus MTX group (14.5%) (P < 0.001). ACR50 response rates with the 20-mg, 40-mg, and 80-mg adalimumab dosages (31.9%, 55.2%, and 42.5%, respectively) were significantly greater than that with placebo (8.1%) (P = 0.003, P < 0.001, and P < 0.001, respectively). The 40-mg and 80-mg doses of adalimumab were associated with an ACR70 response (26.9% and 19.2%, respectively) that was statistically significantly greater than that with placebo (4.8%) (P < 0.001 and P = 0.020). Responses were rapid, with the greatest proportion of adalimumab-treated patients achieving an ACR20 response at the first scheduled visit (week 1). Adalimumab was safe and well tolerated; comparable numbers of adalimumab-treated patients and placebo-treated patients reported adverse events.
Conclusion
The addition of adalimumab at a dosage of 20 mg, 40 mg, or 80 mg administered subcutaneously every other week to long-term MTX therapy in patients with active RA provided significant, rapid, and sustained improvement in disease activity over 24 weeks compared with MTX plus placebo.
1,813 citations
Harvard University1, Duke University2, Yale University3, Washington University in St. Louis4, University of North Carolina at Chapel Hill5, University of California, Los Angeles6, National Institutes of Health7, Stanford University8, Mayo Clinic9, University of Washington10, Rush University Medical Center11, University of Alabama at Birmingham12, University of Miami13
TL;DR: The intervention improved depression and social isolation, although the relative improvement in the psychosocial intervention group compared with the usual care group was less than expected due to substantial improvement in usual care patients.
Abstract: CONTEXT Depression and low perceived social support (LPSS) after myocardial infarction (MI) are associated with higher morbidity and mortality, but little is known about whether this excess risk can be reduced through treatment. OBJECTIVE To determine whether mortality and recurrent infarction are reduced by treatment of depression and LPSS with cognitive behavior therapy (CBT), supplemented with a selective serotonin reuptake inhibitor (SSRI) antidepressant when indicated, in patients enrolled within 28 days after MI. DESIGN, SETTING, AND PATIENTS Randomized clinical trial conducted from October 1996 to April 2001 in 2481 MI patients (1084 women, 1397 men) enrolled from 8 clinical centers. Major or minor depression was diagnosed by modified Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition criteria and severity by the 17-item Hamilton Rating Scale for Depression (HRSD); LPSS was determined by the Enhancing Recovery in Coronary Heart Disease Patients (ENRICHD) Social Support Instrument (ESSI). Random allocation was to usual medical care or CBT-based psychosocial intervention. INTERVENTION Cognitive behavior therapy was initiated at a median of 17 days after the index MI for a median of 11 individual sessions throughout 6 months, plus group therapy when feasible, with SSRIs for patients scoring higher than 24 on the HRSD or having a less than 50% reduction in Beck Depression Inventory scores after 5 weeks. MAIN OUTCOME MEASURES Composite primary end point of death or recurrent MI; secondary outcomes included change in HRSD (for depression) or ESSI scores (for LPSS) at 6 months. RESULTS Improvement in psychosocial outcomes at 6 months favored treatment: mean (SD) change in HRSD score, -10.1 (7.8) in the depression and psychosocial intervention group vs -8.4 (7.7) in the depression and usual care group (P<.001); mean (SD) change in ESSI score, 5.1 (5.9) in the LPSS and psychosocial intervention group vs 3.4 (6.0) in the LPSS and usual care group (P<.001). After an average follow-up of 29 months, there was no significant difference in event-free survival between usual care (75.9%) and psychosocial intervention (75.8%). There were also no differences in survival between the psychosocial intervention and usual care arms in any of the 3 psychosocial risk groups (depression, LPSS, and depression and LPSS patients). CONCLUSIONS The intervention did not increase event-free survival. The intervention improved depression and social isolation, although the relative improvement in the psychosocial intervention group compared with the usual care group was less than expected due to substantial improvement in usual care patients.
1,792 citations
TL;DR: It is suggested that nitrite represents a major bioavailable pool of NO, and a new physiological function for hemoglobin as a nitrite reductase is described, potentially contributing to hypoxic vasodilation.
Abstract: Nitrite anions comprise the largest vascular storage pool of nitric oxide (NO), provided that physiological mechanisms exist to reduce nitrite to NO. We evaluated the vasodilator properties and mechanisms for bioactivation of nitrite in the human forearm. Nitrite infusions of 36 and 0.36 μmol/min into the forearm brachial artery resulted in supra- and near-physiologic intravascular nitrite concentrations, respectively, and increased forearm blood flow before and during exercise, with or without NO synthase inhibition. Nitrite infusions were associated with rapid formation of erythrocyte iron-nitrosylated hemoglobin and, to a lesser extent, S-nitroso-hemoglobin. NO-modified hemoglobin formation was inversely proportional to oxyhemoglobin saturation. Vasodilation of rat aortic rings and formation of both NO gas and NO-modified hemoglobin resulted from the nitrite reductase activity of deoxyhemoglobin and deoxygenated erythrocytes. This finding links tissue hypoxia, hemoglobin allostery and nitrite bioactivation. These results suggest that nitrite represents a major bioavailable pool of NO, and describe a new physiological function for hemoglobin as a nitrite reductase, potentially contributing to hypoxic vasodilation.
1,714 citations
University of Pittsburgh1, University of California, San Francisco2, Ohio State University3, Fred Hutchinson Cancer Research Center4, Harvard University5, University of Alabama at Birmingham6, National Institutes of Health7, Medical College of Wisconsin8, Stanford University9, University at Buffalo10, University of Cincinnati11
TL;DR: It is demonstrated that estrogen plus progestin increases BMD and reduces the risk of fracture in healthy postmenopausal women and there was no net benefit when considering the effects of hormone therapy on other important disease outcomes in a global model.
Abstract: Context In the Women's Health Initiative trial of estrogen-plus-progestin therapy, women assigned to active treatment had fewer fractures. Objective To test the hypothesis that the relative risk reduction of estrogen plus progestin on fractures differs according to risk factors for fractures. Design, setting, and participants Randomized controlled trial (September 1993-July 2002) in which 16 608 postmenopausal women aged 50 to 79 years with an intact uterus at baseline were recruited at 40 US clinical centers and followed up for an average of 5.6 years. Intervention Women were randomly assigned to receive conjugated equine estrogen, 0.625 mg/d, plus medroxyprogesterone acetate, 2.5 mg/d, in 1 tablet (n = 8506) or placebo (n = 8102). Main outcome measures All confirmed osteoporotic fracture events that occurred from enrollment to discontinuation of the trial (July 7, 2002); bone mineral density (BMD), measured in a subset of women (n = 1024) at baseline and years 1 and 3; and a global index, developed to summarize the balance of risks and benefits to test whether the risk-benefit profile differed across tertiles of fracture risk. Results Seven hundred thirty-three women (8.6%) in the estrogen-plus-progestin group and 896 women (11.1%) in the placebo group experienced a fracture (hazard ratio [HR], 0.76; 95% confidence interval [CI], 0.69-0.83). The effect did not differ in women stratified by age, body mass index, smoking status, history of falls, personal and family history of fracture, total calcium intake, past use of hormone therapy, BMD, or summary fracture risk score. Total hip BMD increased 3.7% after 3 years of treatment with estrogen plus progestin compared with 0.14% in the placebo group (P Conclusions This study demonstrates that estrogen plus progestin increases BMD and reduces the risk of fracture in healthy postmenopausal women. The decreased risk of fracture attributed to estrogen plus progestin appeared to be present in all subgroups of women examined. When considering the effects of hormone therapy on other important disease outcomes in a global model, there was no net benefit, even in women considered to be at high risk of fracture.
1,156 citations
TL;DR: The VIVA (Vascular endothelial growth factor in Ischemia for Vascular Angiogenesis) trial as discussed by the authors was designed to evaluate the safety and efficacy of intracoronary and intravenous infusions of rhVEGF.
Abstract: Background— Recombinant human vascular endothelial growth factor protein (rhVEGF) stimulates angiogenesis in animal models and was well tolerated in Phase I clinical trials. VIVA (Vascular endothelial growth factor in Ischemia for Vascular Angiogenesis) is a double-blind, placebo-controlled trial designed to evaluate the safety and efficacy of intracoronary and intravenous infusions of rhVEGF. Methods and Results— A total of 178 patients with stable exertional angina, unsuitable for standard revascularization, were randomized to receive placebo, low-dose rhVEGF (17 ng · kg−1 · min−1), or high-dose rhVEGF (50 ng · kg−1 · min−1) by intracoronary infusion on day 0, followed by intravenous infusions on days 3, 6, and 9. Exercise treadmill tests, angina class, and quality of life assessments were performed at baseline, day 60, and day 120. Myocardial perfusion imaging was performed at baseline and day 60. At day 60, the change in exercise treadmill test (ETT) time from baseline was not different between groups...
977 citations
TL;DR: The results show that dysfunction of dynactin-mediated transport can lead to human motor neuron disease.
Abstract: Impaired axonal transport in motor neurons has been proposed as a mechanism for neuronal degeneration in motor neuron disease. Here we show linkage of a lower motor neuron disease to a region of 4 Mb at chromosome 2p13. Mutation analysis of a gene in this interval that encodes the largest subunit of the axonal transport protein dynactin showed a single base-pair change resulting in an amino-acid substitution that is predicted to distort the folding of dynactin's microtubule-binding domain. Binding assays show decreased binding of the mutant protein to microtubules. Our results show that dysfunction of dynactin-mediated transport can lead to human motor neuron disease.
946 citations
University of Alabama at Birmingham1, University of Texas Health Science Center at Houston2, Veterans Health Administration3, University of Southern California4, Washington University in St. Louis5, University of Michigan6, Tulane University7, Ohio State University8, University of Mississippi Medical Center9, Westchester Medical Center10, University of California, Los Angeles11
TL;DR: Subjects in the observational cohort had higher Acute Physiology and Chronic Health Evaluation II scores than did participants in the clinical trial, which suggests that the former subjects are more often excluded from therapeutic trials.
Abstract: We conducted a prospective, multicenter observational study of adults (n=1447) and children (n=144) with candidemia at tertiary care centers in the United States in parallel with a candidemia treatment trial that included nonneutropenic adults. Candida albicans was the most common bloodstream isolate recovered from adults and children (45% vs. 49%) and was associated with high mortality (47% among adults vs. 29% among children). Three-month survival was better among children than among adults (76% vs. 54%; P<.001). Most children received amphotericin B as initial therapy, whereas most adults received fluconazole. In adults, Candida parapsilosis fungemia was associated with lower mortality than was non-parapsilosis candidemia (24% vs. 46%; P<.001). Mortality was similar among subjects with Candida glabrata or non-glabrata candidemia; mortality was also similar among subjects with C. glabrata candidemia who received fluconazole rather than other antifungal therapy. Subjects in the observational cohort had higher Acute Physiology and Chronic Health Evaluation II scores than did participants in the clinical trial (18.6 vs. 16.1), which suggests that the former subjects are more often excluded from therapeutic trials.
802 citations
TL;DR: In this paper, the authors evaluated the efficacy and safety of ganciclovir therapy in neonates with congenital cytomegalovirus (CMV) disease and found that 20% of the infants had improved hearing or maintained normal hearing between baseline and 6 months versus 10% of 17 control patients.
778 citations
TL;DR: To define Myc's functional role, transgenic mice expressing human c-Myc in the mouse prostate are generated and this approach illustrates how genomic technologies can be applied to mouse cancer models to guide evaluation of human tumor databases.
TL;DR: In this paper, the authors used the standardized 6-min walk test (6MWT) to measure the impact of multiple comorbidities, including cardiovascular disease, lung disease, arthritis, diabetes and cognitive dysfunction and depression, on exercise capacity and endurance in older adults.
TL;DR: To evaluate the validity and reliability of a standardized approach for assessing life-space mobility and its ability to detect changes in life‐space over time in community‐dwelling older adults.
Abstract: Objectives: To evaluate the validity and reliability of a standardized approach for assessing life-space mobility (the University of Alabama at Birmingham Study of Aging Life-Space Assessment (LSA)) and its ability to detect changes in life-space over time in community-dwelling older adults.
Design: Prospective, observational cohort study.
Setting: Five counties (three rural and two urban) in central Alabama.
Participants: Community-dwelling Medicare beneficiaries (N=306; 46% male, 43% African American) who completed in-home baseline interviews and 2-week and 6-month telephone follow-up interviews.
Measurements: The LSA assessed the range, independence, and frequency of movement over the 4 weeks preceding assessments. Correlations between the baseline LSA and measures of physical and mental health (physical performance, activities of daily living, instrumental activities of daily living, a global measure of health (the short form-12 question survey), the Geriatric Depression Scale, and comorbidities) established validity. Follow-up LSA scores established short-term test-retest reliability and the ability of the LSA to detect change.
Results: For all LSA scoring methods, baseline and 2-week follow-up LSA correlations were greater than 0.86 (95% confidence interval=0.82–0.97). Highest correlations with measures of physical performance and function were noted for the LSA scoring method considering all attributes of mobility. The LSA showed both increases and decreases at 6 months.
Discussion: Life-space correlated with observed physical performance and self-reported function. It was stable over a 2-week period yet showed changes at 6 months.
TL;DR: Primary care physicians view obesity as largely a behavioral problem and share the authors' broader society's negative stereotypes about the personal attributes of obese persons but view obesity treatment as less effective than treatment of most other chronic conditions.
Abstract: Objective This study was designed to assess physicians' attitudes toward obese patients and the causes and treatment of obesity. Research methods and procedures A questionnaire assessed attitudes in 2 geographically representative national random samples of 5000 primary care physicians. In one sample (N = 2500), obesity was defined as a BMI of 30 to 40 kg/m(2), and in the other (N = 2500), obesity was defined as a BMI > 40. Results Six hundred twenty physicians responded. They rated physical inactivity as significantly more important than any other cause of obesity (p Discussion Primary care physicians view obesity as largely a behavioral problem and share our broader society's negative stereotypes about the personal attributes of obese persons. Practitioners are realistic about treatment outcomes but view obesity treatment as less effective than treatment of most other chronic conditions.
TL;DR: Exogenous HA enhances chondrocyte HA and proteoglycan synthesis, reduces the production and activity of proinflammatory mediators and matrix metalloproteinases, and alters the behavior of immune cells.
Abstract: Although the predominant mechanism of intra-articular hyaluronan (hyaluronic acid) (HA) and hylans for the treatment of pain associated with knee osteoarthritis (OA) is unknown, in vivo, in vitro, and clinical studies demonstrate various physiological effects of exogenous HA. HA can reduce nerve impulses and nerve sensitivity associated with the pain of OA. In experimental OA, this glycosaminoglycan has protective effects on cartilage, which may be mediated by its molecular and cellular effects observed in vitro. Exogenous HA enhances chondrocyte HA and proteoglycan synthesis, reduces the production and activity of proinflammatory mediators and matrix metalloproteinases, and alters the behavior of immune cells. Many of the physiological effects of exogenous HA may be a function of its molecular weight. Several physiological effects probably contribute to the mechanisms by which HA and hylans exert their clinical effects in knee OA.
TL;DR: The novel concept that structural and functional abnormalities in the vasculature, including endothelial dysfunction, increased oxidative stress, vascular remodeling, and decreased compliance, may antedate hypertension and contribute to its pathogenesis has gained support in recent years.
Abstract: Increased recognition of specific causes of hypertension may lead to therapies that address specific pathophysiologic mechanisms and cause fewer adverse effects. Research to identify such therapies...
TL;DR: The demographic, reproductive, dietary, and health characteristics of the OS women are described, to provide a comprehensive view of both classical and novel risk factors, as well as secular trends in the predictors of healthy aging and disease events.
TL;DR: These data suggest that beneficial effects may occur during early phases of treatment with beraprost in WHO functional class II or III patients but that this effect attenuates with time.
TL;DR: A complete set of the placental reaction patterns seen with amniotic fluid infection was assembled and validated in the hope that this might provide a standardized diagnostic framework useful for practicing pathologists.
Abstract: Clinically responsive placental examination seeks to provide useful information regarding the etiology, prognosis, and recurrence risk of pregnancy disorders. The purpose of this study was to assemble and validate a complete set of the placental reaction patterns seen with amniotic fluid infection in the hope that this might provide a standardized diagnostic framework useful for practicing pathologists. Study cases (14 with amniotic fluid infection, 6 controls) were reviewed blindly by six pathologists after agreement on a standard set of diagnostic criteria. After analysis of initial results, criteria were refined and a second, overlapping set of cases were reviewed. Majority vote served as the gold standard. Grading and staging of maternal and fetal inflammatory responses was found to be more reproducible using a two- versus three-tiered grading system than a three- versus five-tiered staging system (overall agreement 81% vs. 71%). Sensitivity, specificity, and efficiency for individual observations ranged from 67–100% (24/30 > 90%). Reproducibility was measured by unweighted kappa values and interpreted as follows: 0.6, substantial. Kappa values for the 12 lesions evaluated in 20 cases by the six pathologists were: acute chorioamnionitis/maternal inflammatory response (any, 0.93; severe 0.76; advanced stage, 0.49); chronic (subacute) chorioamnionitis (0.25); acute chorioamnionitis/fetal inflammatory response (any, 0.90; severe, 0.55; advanced stage, 0.52); chorionic vessel thrombi (0.37); peripheral funisitis (0.84); acute villitis (0.90); acute intervillositis/intervillous abscesses (0.65), and decidual plasma cells (0.30). Adoption of this clearly defined, clinically relevant, and pathologically reproducible terminology could enhance clinicopathologic correlation and provide a framework for future clinical research.
TL;DR: The role of key loci or genes in IBD pathophysiology are discussed and the importance of genetic variability and its interactions with the immune system, gut microbiota, and environmental factors in determining pathogenesis is highlighted.
TL;DR: The current status of VLPs as vaccines is reviewed, and the characteristics and problems associated with producingVLPs for different viruses are discussed, showing dramatic effectiveness as candidate vaccines.
TL;DR: Use of progressive addition lenses compared with SVLs slowed the progression of myopia in COMET children by a small, statistically significant amount only during the first year, and provided some support for the COMET rationale, a role for defocus in progression ofMyopia.
Abstract: Purpose The purpose of the Correction of Myopia Evaluation Trial (COMET) was to evaluate the effect of progressive addition lenses (PALs) compared with single vision lenses (SVLs) on the progression of juvenile-onset myopia. Methods COMET enrolled 469 children (ages 6-11 years) with myopia between -1.25 and -4.50 D spherical equivalent. The children were recruited at four colleges of optometry in the United States and were ethnically diverse. They were randomly assigned to receive either PALs with a +2.00 addition (n = 235) or SVLs (n = 234), the conventional spectacle treatment for myopia, and were followed for 3 years. The primary outcome measure was progression of myopia, as determined by autorefraction after cycloplegia with 2 drops of 1% tropicamide at each annual visit. The secondary outcome measure was change in axial length of the eyes, as assessed by A-scan ultrasonography. Child-based analyses (i.e., the mean of the two eyes) were used. Results were adjusted for important covariates, by using multiple linear regression. Results Of the 469 children (mean age at baseline, 9.3 +/- 1.3 years), 462 (98.5%) completed the 3-year visit. Mean (+/-SE) 3-year increases in myopia (spherical equivalent) were -1.28 +/- 0.06 D in the PAL group and -1.48 +/- 0.06 D in the SVL group. The 3-year difference in progression of 0.20 +/- 0.08 D between the two groups was statistically significant (P = 0.004). The treatment effect was observed primarily in the first year. The number of prescription changes differed significantly by treatment group only in the first year. At 6 months, 17% of the PAL group versus 30% of the SVL group needed a prescription change (P = 0.0007), and, at 1 year, 43% of the PAL group versus 59% of the SVL group required a prescription change (P = 0.002). Interaction analyses identified a significantly larger treatment effect of PALs in children with lower versus higher baseline accommodative response at near (P = 0.03) and with lower versus higher baseline myopia (P = 0.04). Mean (+/- SE) increases in the axial length of eyes of children in the PAL and SVL groups, respectively, were: 0.64 +/- 0.02 mm and 0.75 +/- 0.02 mm, with a statistically significant 3-year mean difference of 0.11 +/- 0.03 mm (P = 0.0002). Mean changes in axial length correlated with those in refractive error (r = 0.86 for PAL and 0.89 for SVL). Conclusions Use of PALs compared with SVLs slowed the progression of myopia in COMET children by a small, statistically significant amount only during the first year. The size of the treatment effect remained similar and significant for the next 2 years. The results provide some support for the COMET rationale-that is, a role for defocus in progression of myopia. The small magnitude of the effect does not warrant a change in clinical practice.
TL;DR: The mitogen‐activated protein (MAP) kinases are a large family of proline‐directed, serine/threonine kinases that require tyrosine and threonine phosphorylation of a TxY motif in the activation loop for activation through aosphorylation cascade involving a MAPKKK, MAPKK and MAPK, often referred to as the MAP kinase module.
Abstract: The mitogen-activated protein (MAP) kinases are a large family of proline-directed, serine/threonine kinases that require tyrosine and threonine phosphorylation of a TxY motif in the activation loop for activation through a phosphorylation cascade involving a MAPKKK, MAPKK and MAPK, often referred to as the MAP kinase module. Three separate such modules have been identified, based on the TxY motif of the MAP kinase and the dual-specificity kinases that strictly phosphorylate their specific TxY sequence. They are the extracellular signal regulated kinases (ERKs), c-jun N-terminal kinases (JNKs) and p38 MAPKs. The ERKs are mainly associated with proliferation and differentiation while the JNKs and p38MAP kinases regulate responses to cellular stresses. Redox homeostasis is critical for proper cellular function. While reactive oxygen species (ROS) and oxidative stress have been implicated in injury, a rapidly growing literature suggests that a transient increase in ROS levels is an important mediator of proliferation and results in activation of various signaling molecules and pathways, among which the MAP kinases. This review will summarize the role of ROS in MAP kinase activation in various systems, including in macrophages, cells of myeloid origin that play an essential role in inflammation and express a multi-component NADPH oxidase that catalyzes the receptor-regulated production of ROS.
Harvard University1, University of British Columbia2, Brigham and Women's Hospital3, Vanderbilt University Medical Center4, University of Rochester5, Columbia University6, University of Alabama at Birmingham7, University of Pittsburgh8, International AIDS Society9, University of California, San Diego10
TL;DR: The International AIDS Society-USA convened a panel of physicians and scientists with expertise in antiretroviral drug management, HIV-1 drug resistance, and patient care to provide updated recommendations for HIV- 1 resistance testing.
Abstract: New information about the benefits and limitations of testing for resistance to human immunodeficiency virus (HIV) type 1 (HIV-1) drugs has emerged. The International AIDS Society-USA convened a panel of physicians and scientists with expertise in antiretroviral drug management, HIV-1 drug resistance, and patient care to provide updated recommendations for HIV-1 resistance testing. Published data and presentations at scientific conferences, as well as strength of the evidence, were considered. Properly used resistance testing can improve virological outcome among HIV-infected individuals. Resistance testing is recommended in cases of acute or recent HIV infection, for certain patients who have been infected as long as 2 years or more prior to initiating therapy, in cases of antiretroviral failure, and during pregnancy. Limitations of resistance testing remain, and more study is needed to refine optimal use and interpretation.
TL;DR: Joint VCT prompted sustained but imperfect condom use in HIV discordant couples, and biological markers were insensitive but provided evidence for a significant under-reporting of unprotected sex.
Abstract: Background and objectives: Sexual behavior following voluntary HIV counseling and testing (VCT) is described in 963 cohabiting heterosexual couples with one HIV positive and one HIV negative partner (‘discordant couples’). Biological markers were used to assess the validity of self-report. Methods: Couples were recruited from a same-day VCT center in Lusaka Zambia. Sexual exposures with and without condoms were recorded at 3-monthly intervals. Sperm detected on vaginal smears pregnancy and sexually transmitted diseases (STD) including HIV gonorrhea syphilis and Trichomonas vaginalis were assessed. Results: Less than 3% of couples reported current condom use prior to VCT. In the year after VCT > 80% of reported acts of intercourse in discordant couples included condom use. Reporting 100% condom use was associated with 39–70% reductions in biological markers; however most intervals with reported unprotected sex were negative for all biological markers. Under-reporting was common: 50% of sperm and 32% of pregnancies and HIV transmissions were detected when couples had reported always using condoms. Positive laboratory tests for STD and reported extramarital sex were relatively infrequent. DNA sequencing confirmed that 87% of new HIV infections were acquired from the spouse. Conclusions: Joint VCT prompted sustained but imperfect condom use in HIV discordant couples. Biological markers were insensitive but provided evidence for a significant under-reporting of unprotected sex. Strategies that encourage truthful reporting of sexual behavior and sensitive biological markers of exposure are urgently needed. The impact of prevention programs should be assessed with both behavioral and biological measures. (authors)
University of Texas Health Science Center at Houston1, University of Alabama at Birmingham2, Baylor University3, University of Southern California4, New York Medical College5, Washington University in St. Louis6, Tulane Medical Center7, University of Michigan8, University of Mississippi9, Ohio State University10
TL;DR: Although no established interpretative breakpoints are available for the candins (CFG, MFG, and AFG) and the new azoles (VOR and POS), they all exhibited excellent antifungal activity, even for those strains resistant to the other aforementioned agents.
Abstract: Candida bloodstream isolates (n = 2,000) from two multicenter clinical trials carried out by the National Institute of Allergy and Infectious Diseases Mycoses Study Group between 1995 and 1999 were tested against amphotericin B (AMB), flucytosine (5FC), fluconazole (FLU), itraconazole (ITR), voriconazole (VOR), posaconazole (POS), caspofungin (CFG), micafungin (MFG), and anidulafungin (AFG) using the NCCLS M27-A2 microdilution method. All drugs were tested in the NCCLS-specified RPMI 1640 medium except for AMB, which was tested in antibiotic medium 3. A sample of isolates was also tested in RPMI 1640 supplemented to 2% glucose and by using the diluent polyethylene glycol (PEG) in lieu of dimethyl sulfoxide for those drugs insoluble in water. Glucose supplementation tended to elevate the MIC, whereas using PEG tended to decrease the MIC. Trailing growth occurred frequently with azoles. Isolates were generally susceptible to AMB, 5FC, and FLU. Rates of resistance to ITR approached 20%. Although no established interpretative breakpoints are available for the candins (CFG, MFG, and AFG) and the new azoles (VOR and POS), they all exhibited excellent antifungal activity, even for those strains resistant to the other aforementioned agents.
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31 Jan 2003TL;DR: In this paper, the authors describe some of the processing techniques for CMCs, followed by a description of some salient characteristics of CMC composites regarding interface and mechanical properties and, in particular, the various possible toughness mechanisms.
Abstract: Ceramic materials in general have a very attractive package of properties: high strength and high stiffness at very high temperatures, chemical inertness, low density, and so on. This attractive package is marred by one deadly flaw, namely, an utter lack of toughness. They are prone to catastrophic failures in the presence of flaws (surface or internal). They are extremely susceptible to thermal shock and are easily damaged during fabrication and/or service. It is therefore understandable that an overriding consideration in ceramic matrix composites (CMCs) is to toughen the ceramics by incorporating fibers in them and thus exploit the attractive high-temperature strength and environmental resistance of ceramic materials without risking a catastrophic failure. It is worth pointing out at the very outset that there are certain basic differences between CMCs and other composites. The general philosophy in nonceramic matrix composites is to have the fiber bear a greater proportion of the applied load. This load partitioning depends on the ratio of fiber and matrix elastic moduli, Ef/Em. In nonceramic matrix composites, this ratio can be very high, while in CMCs, it is rather low and can be as low as unity; think of alumina fiber reinforced alumina matrix composite. Another distinctive point regarding CMCs is that because of limited matrix ductility and generally high fabrication temperature, thermal mismatch between components has a very important bearing on CMC performance. The problem of chemical compatibility between components in CMCs has ramifications similar to those in, say, MMCs. We first describe some of the processing techniques for CMCs, followed by a description of some salient characteristics of CMCs regarding interface and mechanical properties and, in particular, the various possible toughness mechanisms, and finally a description of some applications of CMCs.
Boston University1, Technische Universität München2, University of Alabama at Birmingham3, University of British Columbia4, University of Miami5, University of Washington6, University of Southern California7, Morehouse School of Medicine8, Case Western Reserve University9, Medical University of South Carolina10
TL;DR: Depression symptoms before the onset of AD are associated with the development of AD, even in families where first depression symptoms occurred more than 25 years before the start of AD.
Abstract: Background Depression symptoms may be associated with the development of Alzheimer disease (AD). Objectives To evaluate the association between depression symptoms and risk of AD, and to explore the temporal aspects of this association. Setting Academic institutions with specialized memory clinics. Design Cross-sectional, family-based, case-control study with standardized self- and proxy questionnaires to collect information on depression symptoms and other risk factors. Participants A total of 1953 subjects with AD and 2093 of their unaffected relatives enrolled in the Multi-institutional Research in Alzheimer's Genetic Epidemiology Study. Main Outcome Measures Odds ratios (ORs) of AD were estimated with and without depression symptoms, adjusted for age, sex, education, history of head trauma, and apolipoprotein E status. Results There was a significant association between depression symptoms and AD (adjusted OR, 2.13; 95% confidence interval [CI], 1.71-2.67). In families where depression symptoms first occurred within 1 year before the onset of AD, the association was higher (OR, 4.57; 95% CI, 2.87-7.31), while in the families where the depression symptoms first occurred more than 1 year before the onset of AD, the association was lower (OR, 1.38; 95% CI, 1.03-1.85). In families where depression symptoms first occurred more than 25 years before the onset of AD, there was still a modest association (OR, 1.71; 95% CI, 1.03-2.82). Conclusions Depression symptoms before the onset of AD are associated with the development of AD, even in families where first depression symptoms occurred more than 25 years before the onset of AD. These data suggest that depression symptoms are a risk factor for later development of AD.
TL;DR: Mrinone may have a bidirectional effect based on etiology in decompensated HF, but neutral to beneficial in nonischemic cardiomyopathy.
TL;DR: Speed-of-processing training, but not simulator training, improved a specific measure of useful field of view (UFOV®), transferred to some simulator measures, and resulted in fewer dangerous maneuvers during the driving evaluation.
Abstract: Useful field of view, a measure of processing speed and spatial attention, can be improved with training. We evaluated the effects of this improvement on older adults' driving performance. Elderly adults participated in a speed-of-processing training program (N = 48), a traditional driver training program performed in a driving simulator (N = 22), or a low-risk reference group (N = 25). Before training, immediately after training or an equivalent time delay, and after an 18-month delay each participant was evaluated in a driving simulator and completed a 14-mile (22.5-km) open-road driving evaluation. Speed-of-processing training, but not simulator training, improved a specific measure of useful field of view (UFOV), transferred to some simulator measures, and resulted in fewer dangerous maneuvers during the driving evaluation. The simulator-trained group improved on two driving performance measures: turning into the correct lane and proper signal use. Similar effects were not observed in the speed-of-processing training or low-risk reference groups. The persistence of these effects over an 18-month test interval was also evaluated. Actual or potential applications of this research include driver assessment and/or training programs and cognitive intervention programs for older adults.