Showing papers by "Veterans Health Administration published in 1992"
TL;DR: It is concluded that the adapted comorbidity index will be useful in studies of disease outcome and resource use employing administrative databases.
9,805 citations
TL;DR: A brain-systems framework for understanding memory phenomena is developed in light of lesion studies involving rats, monkeys, and humans, as well as recent studies with normal humans using the divided visual field technique, event-related potentials, and positron emission tomography (PET).
Abstract: The topic of multiple forms of memory is considered from a biological point of view. Fact-and-event (declarative, explicit) memory is contrasted with a collection of non conscious (non-declarative, implicit) memory abilities including skills and habits, priming, and simple conditioning. Recent evidence is reviewed indicating that declarative and non declarative forms of memory have different operating characteristics and depend on separate brain systems. A brain-systems framework for understanding memory phenomena is developed in light of lesion studies involving rats, monkeys, and humans, as well as recent studies with normal humans using the divided visual field technique, event-related potentials, and positron emission tomography (PET).
1,191 citations
TL;DR: This work demonstrates complete linkage of GRA in a large kindred to a gene duplication arising from unequal crossing over, fusing the 5' regulatory region of 11β-hydroxylase to the coding sequences of aldosterone synthase.
Abstract: Glucocorticoid-remediable aldosteronism (GRA), an autosomal dominant disorder, is characterized by hypertension with variable hyperaldosteronism and by high levels of the abnormal adrenal steroids 18-oxocortisol and 18-hydroxycortisol, which are all under control of adrenocorticotropic hormone and suppressible by glucocorticoids. These abnormalities could result from ectopic expression of aldosterone synthase, which is normally expressed only in adrenal glomerulosa, in the adrenal fasciculata. Genes encoding aldosterone synthase and steroid 11 beta-hydroxylase (expressed in both adrenal fasciculata and glomerulosa), which are 95% identical and lie on chromosome 8q (refs 7, 10), are therefore candidate genes for GRA. Here we demonstrate complete linkage of GRA in a large kindred to a gene duplication arising from unequal crossing over, fusing the 5' regulatory region of 11 beta-hydroxylase to the coding sequences of aldosterone synthase (maximum lod score 5.23 for complete linkage, odds ratio of 170,000:1). This mutation can account for all the physiological abnormalities of GRA. Our result represents the demonstration of a mutation causing hypertension in otherwise phenotypically normal animals or humans.
1,064 citations
TL;DR: In dispersed acini from guinea pig pancreas, natural and synthetic exendin-4 stimulate a monophasic increase in cAMP beginning at 100 pM that plateaus at 10 nM, which indicates that in dispersed pancreatic acini, exendIn-4 interacts only with the recently describedExendin receptor.
1,023 citations
TL;DR: Evidence indicates a familial Alzheimer's disease locus on chromosome 14, which is found in early-onset non-Volga German kindreds, and results for the Volga German families were either negative or nonsignificant for markers in this region.
Abstract: Linkage analysis was used to search the genome for chromosomal regions harboring familial Alzheimer's disease genes. Markers on chromosome 14 gave highly significant positive lod scores in early-onset non-Volga German kindreds; a Zmax of 9.15 (theta = 0.01) was obtained with the marker D14S43 at 14q24.3. One early-onset family yielded a lod score of 4.89 (theta = 0.0). When no assumptions were made about age-dependent penetrance, significant results were still obtained (Zmax = 5.94, theta = 0.0), despite the loss of power to detect linkage under these conditions. Results for the Volga German families were either negative or nonsignificant for markers in this region. Thus, evidence indicates a familial Alzheimer's disease locus on chromosome 14.
931 citations
TL;DR: Most causes of back pain respond to symptomatic and physical measures, but some are surgically remediable and some are systemic diseases requiring specific therapy, so careful diagnostic evaluation is important.
Abstract: BACK pain ranks second only to upper respiratory illness as a symptomatic reason for office visits to physicians.1About 70% of adults have low back pain at some time, but only 14% have an episode that lasts more than 2 weeks. About 1.5% have such episodes with features of sciatica.2,3Most causes of back pain respond to symptomatic and physical measures, but some are surgically remediable and some are systemic diseases (cancer or disseminated infection) requiring specific therapy, so careful diagnostic evaluation is important. Features of the clinical history and physical examination influence not only therapeutic choices but also decisions about diagnostic imaging, laboratory testing, and specialist referral. ANATOMIC/PHYSIOLOGIC ORIGINS OF FINDINGS IN THE LOW BACK Low back pain may arise from several structures in the lumbar spine, including the ligaments that interconnect vertebrae, outer fibers of the annulus fibrosus, facet joints, vertebral periosteum, paravertebral musculature and fascia,
902 citations
TL;DR: The results provide evidence for selective activation of the human hippocampal region in association with memory function and lead to a suggestion about the neural basis of repetition priming: following presentation of a stimulus, less neural activity is required to process the same stimulus.
Abstract: We studied regional cerebral blood flow using the H2(15)O method while normal subjects performed four similar tasks involving three-letter word beginnings (stems). Prior to each task, subjects studied a list of words. Local blood flow was then monitored during a 40-sec period while subjects (i) silently viewed word stems, (ii) completed stems to form the first words to come to mind, but the stems were not the beginnings of any study words (baseline), (iii) completed stems and half of them could form study words (priming), or (iv) tried to recall study words, and half of the stems could form these words (memory). There were three major findings. (i) The memory task engaged the right hippocampal region when the memory task was compared to either the baseline or the priming condition. The right hemispheric locus suggests that performance is driven by the visual characteristics of the words rather than by semantic or phonetic analysis. (ii) In the priming-minus-baseline comparison, there was reduction in blood flow in the right posterior cortex. (iii) Right prefrontal cortex was activated in the memory-minus-baseline condition. The results provide evidence for selective activation of the human hippocampal region in association with memory function. The results also lead to a suggestion about the neural basis of repetition priming: following presentation of a stimulus, less neural activity is required to process the same stimulus.
827 citations
TL;DR: Hypertension can cause or is related to various cardiac manifestations, among them left ventricular hypertrophy, congestive heart failure, cardiac dysrhythmias, and ischemic heart disease.
Abstract: HYPERTENSIVE heart disease can be defined as the response of the heart to the afterload imposed on the left ventricle by the progressively increasing arterial pressure and total peripheral resistance produced by hypertensive vascular disease. Although the response sometimes appears to be out of proportion to the level of the arterial pressure, it is primarily the result of the hemodynamic overload. Hypertension can cause or is related to various cardiac manifestations, among them left ventricular hypertrophy, congestive heart failure, cardiac dysrhythmias, and ischemic heart disease. Although the risk of atherosclerotic coronary heart disease is related to the systolic and diastolic . . .
742 citations
TL;DR: It is concluded that functional reach is a simple and easy-to-use clinical measure that has predictive validity in identifying recurrent falls in elderly subjects at risk for recurrent falls.
Abstract: Focus groups were used to explore a range of issues concerning breast cancer screening in elderly women and to contribute to defining a research agenda. Two groups consisted of women aged 65-75 and 75 and older, and one group consisted of primary care physicians. Predominant topic areas were women's awareness of breast cancer and screening information, attitudes and perceived barriers to screening (including those related to women themselves, to the health care system, and to physicians), issues related to relationships within the medical community, and opinions about and priorities for change.
720 citations
TL;DR: For patients with single-vessel coronary artery disease, PTCA offers earlier and more complete relief of angina than medical therapy and is associated with better performance on the exercise test.
Abstract: Background. Despite the widespread use of percutaneous transluminal coronary angioplasty (PTCA), only a few prospective trials have assessed its efficacy. We compared the effects of PTCA with those of medical therapy on angina and exercise tolerance in patients with stable single-vessel coronary artery disease. Methods. Patients with 70 to 99 percent stenosis of one epicardial coronary artery and with exercise-induced myocardial ischemia were randomly assigned either to undergo PTCA or to receive medical therapy and were evaluated monthly. The patients assigned to PTCA were urged to have repeat angioplasty if their symptoms suggested re-Stenosis. After six months, all the patients had repeat exercise testing and coronary angiography. Results. A total of 107 patients were randomly assigned to medical therapy and 105 to PTCA. PTCA was clinically successful in 80 of the 100 patients who actually had the procedure, with an initial reduction in mean percent stenosis from 76 to 36 percent. Two patients in the P...
694 citations
TL;DR: In vitro evidence suggests, for the first time, a mechanistic paradigm by which estrogens might exert at least part of their antiresorptive influence on the skeleton.
Abstract: The effect of 17 beta-estradiol on interleukin-6 (IL-6) synthesis was examined in murine bone marrow-derived stromal cell lines, normal human bone-derived cells, and nontransformed osteoblast cell lines from mice and rats. In all these cell types IL-6 production was stimulated as much as 10,000-fold in response to the combination of recombinant interleukin-1 (IL-1) and tumor necrosis factor alpha (TNF alpha). Addition of 17 beta-estradiol in the cultures exerted a dose-dependent inhibition of IL-1-, TNF-, and IL-1 + TNF-induced production of bioassayable IL-6. Testosterone and progesterone (but not 17 alpha-estradiol) also inhibited IL-6, but their effective concentrations were two orders of magnitude higher than 17 beta-estradiol. 17 beta-estradiol also decreased the levels of the IL-6 mRNA. In addition, estradiol inhibited both TNF-induced IL-6 production and osteoclast development in primary bone cell cultures derived from neonatal murine calvaria. The TNF-stimulated osteoclast development was also suppressed by a neutralizing monoclonal anti-IL-6 antibody. This in vitro evidence suggests, for the first time, a mechanistic paradigm by which estrogens might exert at least part of their antiresorptive influence on the skeleton.
TL;DR: Valproate is as effective as carbamazepine for the treatment of generalized tonic-clonic seizures, but carbamazetine provides better control of complex partial seizures and has fewer long-term adverse effects.
Abstract: Background. Valproate is approved for use primarily in patients with absence seizures, but the drug has a broad spectrum of activity against seizures of all types. Partial or secondarily generalized tonic—clonic seizures are often difficult to control adequately with standard treatment, usually carbamazepine or phenytoin. Methods. We conducted a multicenter, double-blind trial that compared valproate with carbamazepine in the treatment of 480 adults with complex partial seizures (206 patients) or secondarily generalized tonic—clonic seizures (274 patients). The patients were randomly assigned to treatment with carbamazepine or divalproex sodium (valproate) at doses adjusted to achieve blood levels in the middle of the therapeutic range. Patients were followed for one to five years or until seizures became uncontrollable, treatment had unacceptable adverse effects, or both these events occurred. Results. For the control of secondarily generalized tonic—clonic seizures, carbamazepine and valproate ...
TL;DR: Patients with transfusion-related non-A, non-B hepatitis who had been identified in five major prospective studies conducted in the United States between 1967 and 1980 are traced.
Abstract: Background. Acute non-A, non-B hepatitis after blood transfusion often progresses to chronic hepatitis and sometimes culminates in cirrhosis or even hepatocellular carcinoma. However, the frequency of these sequelae and their effects on mortality are not known. Methods. We traced patients with transfusion-related non-A, non-B hepatitis who had been identified in five major prospective studies conducted in the United States between 1967 and 1980. We matched each patient with two control subjects (identified as the first and second controls) who received transfusions but who did not have hepatitis. The mortality rates in the three groups were determined with use of data from the National Death Index and Social Security Death Tapes. Cause-specific mortality was determined by reviewing death certificates. Results. Vital status was established for over 94 percent of the 568 patients who had had non-A, non-B hepatitis and the two control groups (526 first controls and 458 second controls). After an ave...
TL;DR: This randomized trial compared endoscopic sclerotherapy and endoscopic ligation in 129 patients with cirrhosis who had proved bleeding from esophageal varices and determined the incidence of complications and recurrences of bleeding, the number of treatments needed to eradicate varices, and survival.
Abstract: Background. Endoscopic sclerotherapy is an accepted treatment for bleeding esophageal varices, but it is associated with substantial local and systemic complications. Endoscopic ligation, a new form of endoscopic treatment for bleeding varices, may be safer. We compared the effectiveness and safety of the two techniques. Methods. In this randomized trial we compared endoscopic sclerotherapy and endoscopic ligation in 129 patients with cirrhosis who had proved bleeding from esophageal varices. Sixty-five patients were treated with sclerotherapy, and 64 with ligation. Initial treatment for acute bleeding was followed by elective retreatment to eradicate varices. The patients were followed for a mean of 10 months, during which we determined the incidence of complications and recurrences of bleeding, the number of treatments needed to eradicate varices, and survival. Results. Active bleeding at the first treatment was controlled by sclerotherapy in 10 of 13 patients (77 percent) and by ligation in 12...
TL;DR: It is concluded that triple therapy is effective for eradication of H. pylori and that future studies need to take compliance into account for comparisons between regimens.
TL;DR: The increased brain tissue loss with advanced age is interpreted as evidence for age-related increase in brain vulnerability to chronic alcohol abuse.
Abstract: Magnetic resonance imaging (MRI) was used to study in vivo the brains of 49 patients with chronic alcoholism, 3 to 4 weeks post-withdrawal, and 43 normal healthy controls, all right-handed male veterans between the ages of 23 and 70 years. MRI scans were analyzed using a semi-automated procedure, which allowed the subcortical regions to be segmented into cerebrospinal fluid (CSF) and brain tissue and the cortical regions to be segmented into CSF, gray matter, and white matter. An age regression model was used to examine the effects of alcohol on brain structure, over and above that expected from the normal aging process. The alcoholics exhibited decreased tissue and increased CSF after correcting for aging. In the cortex, there was significant loss of both gray matter and white matter volume. In this sample of alcoholics, no particular cortical region was preferentially affected or spared. Furthermore, brain tissue volume loss increased with advanced age in the alcoholics. In this group of alcoholics there was no relationship between length of illness and age, i.e., the younger alcoholics had as heavy alcohol use histories as did the older alcoholics. Thus, the increased brain tissue loss with advanced age is interpreted as evidence for age-related increase in brain vulnerability to chronic alcohol abuse.
TL;DR: A 68-year-old man who received an IV inoculation of WBCs for an indium radionuclide scan containing 600 to 700 tissue culture infectious doses of human immunodeficiency virus type 1 from an HIV-1-infected individual dies of hepatorenal syndrome and hepatic encephalopathy 15 days later.
Abstract: We report a 68-year-old man who received an IV inoculation of WBCs for an indium radionuclide scan containing 600 to 700 tissue culture infectious doses of human immunodeficiency virus type 1 (HIV-1) from an HIV-1-infected individual. The recipient immediately received zidovudine, then was switched to dideoxyinosine and interferon-alpha, but died of hepatorenal syndrome and hepatic encephalopathy 15 days later. HIV-1 cultures were positive from the recipient's blood on day 14 but not days 0, 1, and 8. At autopsy, cultures of parietal lobe isolated HIV-1. HIV-1 nucleic acid was present in several brain areas, but not in several other organs, by two independent laboratories using the polymerase chain reaction. The brain showed mild perivascular cuffing and a mild lymphocytic meningitis, but there was no evidence of glial nodules, giant cells, or white matter abnormalities. HIV-1 pg41 viral antigen was seen by immunoperoxidase staining in rare infiltrating cells within perivascular and subpial spaces. Thus, HIV-1 was isolated from brain 15 days after mistaken HIV-1 inoculation and 1 day after virus was first recovered from blood.
TL;DR: In the absence of an epidemic of meningocococcal disease, S. pneumoniae is the most common cause of bacterial meningitis in adults and the second most common in young children, ranking behind Haemophilus influenzae type b.
Abstract: Virtually every attempt to rank bacterial causes of community-acquired pneumonia in adults has placed Streptococcus pneumoniae at the top of the list, although the actual proportion of cases of pneumonia proven to be caused by this organism has varied from 15% to 76% in representative series. In the absence of an epidemic of meningocococcal disease, S. pneumoniae is also the most common cause of bacterial meningitis in adults and the second most common in young children, ranking behind Haemophilus influenzae type b. Blood cultures are positive in 15%-30% of cases of pneumococcal pneumonia, depending upon the population under study and, to a lesser extent, the serotype. Bacteremia-so-called primary bacteremia-may occur without an apparent source; when the disease is associated with an acute, nonspecific febrile illness in young children, harmful consequences may result if antibiotic therapy is not given. Pneumococcal empyema, endocarditis, and pericarditis occur, albeit much less commonly now than in former years. Septic arthritis, osteomyelitis, and peritonitis are seen only infrequently. Other syndromes of serious infection, such as brain abscess, pyomyositis, and peritonitis, are rare. Among less serious disease states, such as otitis media or acute sinusitis, S. pneumoniae remains the most commonly isolated bacterial pathogen when carefully aspirated material is cultured.
TL;DR: Results showing increased endogenous nitrate synthesis in patients receiving IL-2 demonstrate for the first time that a cytokine-inducible, high-output L-arginine/NO pathway exists in humans.
Abstract: An interferon-gamma, tumor necrosis factor, and interleukin-1-inducible, high-output pathway synthesizing nitric oxide (NO) from L-arginine was recently identified in rodents. High-dose interleukin-2 (IL-2) therapy is known to induce the same cytokines in patients with advanced cancer. Therefore, we examined renal cell carcinoma (RCC; n = 5) and malignant melanoma (MM; n = 7) patients for evidence of cytokine-inducible NO synthesis. Activity of this pathway was evaluated by measuring serum and urine nitrate (the stable degradation product of NO) during IL-2 therapy. IL-2 administration caused a striking increase in NO generation as reflected by serum nitrate levels (10- and 8-fold increase [P less than 0.001, P less than 0.003] for RCC and MM patients, respectively) and 24-h urinary nitrate excretion (6.5- and 9-fold increase [both P less than 0.001] for RCC and MM patients, respectively). IL-2-induced renal dysfunction made only a minor contribution to increased serum nitrate levels. Metabolic tracer studies using L-[guanidino-15N2]arginine demonstrated that the increased nitrate production was derived from a terminal guanidino nitrogen atom of L-arginine. Our results showing increased endogenous nitrate synthesis in patients receiving IL-2 demonstrate for the first time that a cytokine-inducible, high-output L-arginine/NO pathway exists in humans.
TL;DR: Clinical outcomes did not differ by diagnosis or fusion technique, but were worse in studies with a greater number of previously operated patients, and complications of fusions are common.
Abstract: Objectives. —To determine success and complication rates for lumbar spinal fusion surgery, predictors of good outcomes, and whether fusion improves success rates of laminectomy for specific low back disorders. Data Sources. —English-language journal articles published from 1966 through April 1991, identified through MEDLINE searching ( spinalfusion plus limiting terms), bibliography review, and expert consultation. Study Selection. —Articles were selected only if they reported at least 1 year of follow-up data enabling the classification of clinical outcomes as satisfactory or unsatisfactory for at least 30 patients. Data Extraction. —Two reviewers independently extracted data on patient characteristics, surgical methods, patient outcomes, and quality of study methods. Data Synthesis. —Of 47 articles, there were no randomized trials. Four nonrandomized studies compared surgery with and without fusion for herniated disks; three found no advantage for fusion. On average, 68% of patients had a satisfactory outcome after fusion, but the range was wide (16% to 95%), and the satisfactory outcome rate was lower in prospective than in retrospective studies. The most frequently reported complications were pseudarthrosis (14%) and chronic pain at the bone graft donor site (9%). Clinical outcomes did not differ by diagnosis or fusion technique, but were worse in studies with a greater number of previously operated patients. Conclusions. —For several low back disorders no advantage has been demonstrated for fusion over surgery without fusion, and complications of fusions are common. Randomized controlled trials are needed to compare fusion, surgery without fusion, and nonsurgical treatments in rigorously defined patient groups. ( JAMA . 1992;268:907-911)
TL;DR: The data corroborated Wunderlich's in that mean temperature varied diurnally, with a 6 AM nadir, a 4 to 6 PM zenith, and a mean amplitude of variability of 0.5 degrees C (0.9 degrees F); women had slightly higher normal temperatures than men; and there was a trend toward higher temperatures among black than among white subjects.
Abstract: Objective. —To evaluate critically Carl Wunderlich's axioms on clinical thermometry. Design. —Descriptive analysis of baseline oral temperature data from volunteers participating inShigellavaccine trials conducted at the University of Maryland Center for Vaccine Development, Baltimore. Setting. —Inpatient clinical research unit. Participants. —One hundred forty-eight healthy men and women aged 18 through 40 years. Main Measurements. —Oral temperatures were measured one to four times daily for 3 consecutive days using an electronic digital thermometer. Results. —Our findings conflicted with Wunderlich's in that 36.8°C (98.2°F) rather than 37.0°C (98.6°F) was the mean oral temperature of our subjects; 37.7°C (99.9°F) rather than 38.0°C (100.4°F) was the upper limit of the normal temperature range; maximum temperatures, like mean temperatures, varied with time of day; and men and women exhibited comparable thermal variability. Our data corroborated Wunderlich's in that mean temperature varied diurnally, with a 6 AM nadir, a 4 to 6 PM zenith, and a mean amplitude of variability of 0.5°C (0.9°F); women had slightly higher normal temperatures than men; and there was a trend toward higher temperatures among black than among white subjects. Conclusions. —Thirty-seven degrees centigrade (98.6°F) should be abandoned as a concept relevant to clinical thermometry; 37.2°C (98.9°F) in the early morning and 37.7°C (99.9°F) overall should be regarded as the upper limit of the normal oral temperature range in healthy adults aged 40 years or younger, and several of Wunderlich's other cherished dictums should be revised. (JAMA. 1992;268:1578-1580)
TL;DR: Ward admissions hospitalized within the prior 30 days in the medical center were more likely to be culture-positive for C. difficile at admission to the study ward than those not previously hospitalized at the institution (16% vs. 7%, P less than .001), suggesting that C.difficile-colonized new admissions are a major source of nosocomial C. Difficile infections.
Abstract: The frequency of introduction and spread of specific Clostridium difficile strains among hospitalized patients were assessed by serial cultures of patients admitted to a medical-surgical ward with endemic C. difficile-associated diarrhea. Stool cultures were obtained from 634 (94%) of 678 consecutive admissions to the ward (ward admissions), and all C. difficile isolates were typed by restriction endonuclease analysis. Sixty-five ward admissions introduced C. difficile to the ward, and 54 initially culture-negative admissions acquired C. difficile on the ward. Ward admissions hospitalized within the prior 30 days in the medical center were more likely to be culture-positive for C. difficile at admission to the study ward than those not previously hospitalized at the institution (16% vs. 7%, P less than .001). Nosocomial acquisition of a C. difficile strain was preceded by a documented introduction of that strain to the ward by another asymptomatic ward admission in 16 (84%) of 19 instances, suggesting that C. difficile-colonized new admissions are a major source of nosocomial C. difficile infections.
TL;DR: Data support the hypothesis that distal forearm fractures often occur as a result of a fall in women with low bone mineral density who are relatively healthy and active and have good neuromuscular function, while fractures of the proximal humerus tend to occur in women who are less healthy and less active than average.
Abstract: The Study of Osteoporotic Fractures is a prospective cohort study begun in 1986 that includes 9,704 women aged 65 years and older from Maryland, Minnesota, Oregon, and Pennsylvania. A total of 171 women suffered fractures of the distal forearm, and 79 women had fractures of the proximal humerus during the first 2.2 years of follow-up. Most fractures at both sites occurred as a result of a fall. Low bone mineral density was a strong predictor of these fractures; comparing those in the lowest quintile of bone mineral density in the distal radius with those in the highest quintile, the rate ratio was 4.1 for fractures of the distal forearm and 7.5 for fractures of the proximal humerus. Other factors associated with an increased rate of distal forearm fracture independently of low bone mineral density included poor visual acuity, number of falls in the year before baseline, and frequent walking. Factors that appeared to be independently associated with an increased rate of fracture of the proximal humerus included a recent decline in health status, insulin-dependent diabetes mellitus, infrequent walking, and several indicators of neuromuscular weakness such as inability to stand with feet in a tandem position for more than a few seconds. These data support the hypothesis that distal forearm fractures often occur as a result of a fall in women with low bone mineral density who are relatively healthy and active and have good neuromuscular function, while fractures of the proximal humerus tend to occur as a result of a fall in women with low bone mineral density who are less healthy and less active than average and who have poor neuromuscular function.
TL;DR: The schizophrenic group was found to have significantly less gray matter than the control group but no difference in white matter, and regional brain volume measurements need to be expressed in the context of possible widespread gray matter volume deficits in schizophrenia.
Abstract: • Magnetic resonance imaging was used to investigate whether the structural brain differences commonly observed in patients with schizophrenia as compared with normal control subjects are specific to gray or white matter, and furthermore whether such abnormalities are localizable to circumscribed cortical regions. Accordingly, 22 patients meeting DSM-III-R criteria for schizophrenia and 20 healthy community volunteers, all 23 to 45 years old, received magnetic resonance imaging scans. Seven axial magnetic resonance imaging sections of 5-mm thickness were segmented into cerebrospinal fluid, gray matter, and white matter compartments and used for volumetric quantification. For the healthy control subjects, age correlated significantly with the percentage of all magnetic resonance imaging sections taken up by gray matter but not white matter. After correcting for the normal effect of age, the schizophrenic group was found to have significantly less gray matter than the control group but no difference in white matter; ventricular volume was 34% greater in the schizophrenic group. The schizophrenic group had less gray matter in all six cortical subregions analyzed; these differences attained statistical significance for all but the parietal measure. These findings have implications for studies of localized gray matter abnormalities and suggest that regional brain volume measurements need to be expressed in the context of possible widespread gray matter volume deficits in schizophrenia.
TL;DR: Modification of certain risk factors by patients and health professionals may reduce the risk for amputation and thus decrease the human and dollar costs that accompany limb loss in this prevalent chronic disease.
Abstract: Objective To identify and quantify risk factors for lower extremity amputation in persons with diabetes mellitus. Design Case-control study. Setting A Veterans Affairs medical center. Patients Eighty patients having amputation associated with diabetes and 236 diabetic controls without limb lesions were enrolled before surgery from the 21,167 inpatient care and outpatient surgical patients seen at the Seattle Veterans Affairs Medical Center during a 30-month period. Measurements Selected vascular, neuropathic, environmental, health care, self care, nutritional, metabolic, lifestyle, and psychosocial risk factors were measured in all patients before surgery. Results Statistically significant risk factors identified from analysis included insufficient mean below-knee and foot cutaneous circulation (odds ratio, 161; 95% CI, 55.1 to 469); ankle-arm blood pressure index less than 0.45 (odds ratio, 55.8; CI, 14.9 to 209); absence of lower leg vibratory perception (odds ratio, 15.5; CI, 8.3 to 28.7); low levels of high-density lipoprotein (HDL) subfraction 3 less than or equal to 0.7 mumol/L (odds ratio, 4.9; CI, 2.9 to 8.3); and no previous outpatient diabetes education (odds ratio, 3.2; CI, 1.6 to 6.6). A logistic regression analysis done to control for the potentially confounding effects of age; race; socioeconomic status; diabetes duration, type, and severity confirmed these findings and added a statistically significant interaction between foot transcutaneous oxygen tension and peripheral vascular disease history. Clinical interventions to alter these risk factors were identified, including aggressive treatment of infection, diabetes education, protective footwear, and preventive footcare. Conclusions Multiple risk factors exist along the continuum of conditions and events leading to lower extremity amputation in diabetes. Modification of certain risk factors by patients and health professionals may reduce the risk for amputation and thus decrease the human and dollar costs that accompany limb loss in this prevalent chronic disease.
TL;DR: Silent ischemic events were associated with the initiation of life-threatening ventricular arrhythmias in five patients with induced or spontaneous focal coronary-artery spasm and reperfusion, rather than ischemia itself, correlated with the onset of the ventriculararrhythmia.
Abstract: Background Silent myocardial ischemia in patients with coronary atherosclerosis is associated with an increased risk of adverse cardiac events, including sudden death. The relation between silent ischemia and the initiation of potentially fatal ventricular arrhythmias has not been defined, however. Methods As part of a long-term study of sudden cardiac death, data on arrhythmias, coronary anatomy, and responses to ergonovine testing to provoke coronary artery spasm were collected prospectively among survivors of out-of-hospital cardiac arrest who had no flow-limiting coronary artery lesions, prior myocardial infarctions, or other structural causes of cardiac arrest and no angina pectoris. Associations between silent myocardial ischemia due to coronary artery spasm and the occurrence and characteristics of life-threatening ventricular arrhythmias were studied by both invasive and noninvasive techniques. Results Silent ischemic events were associated with the initiation of life-threatening ventricu...
TL;DR: Dissociative symptoms are an important element of the long-term psychopathological response to trauma and are a significantly higher level in patients with PTSD than in patients without PTSD, according to the Dissociative Experiences Scale.
Abstract: Objective: This study compared current dissociative symptoms and dissociation at the time of specific traumatic events in Vietnam combat veterans with posttraumatic stress disorder (PTSD) and Vietnam combat veterans without PTSD. Method: Vietnam combat veterans who sought treatment for PTSD (N=53) were compared to Vietnam combat veterans without PTSD (N=32) who sought treatment for medical problems. Dissociative symptoms were evaluated with the Dissociative Experiences Scale. Dissociation at the time ofa combat-related traumatic event was evaluated retrospectively with the modified Dissociative Experiences Questionnaire. The Combat Exposure Scale was used to measure level of combat exposure. Results: There was a significantly higher level of dissociative symptoms, as measured by the Dissociative Experiences Scale, in patients with PTSD (mean=27.O, SD=1 8.0) than in patients without PTSD (mean=13.7, SD=1 6.0). This difference persisted when the difference in level of combat exposure was controlled with analysis of covariance. PTSD patients also reported more dissociative symptoms at the time of combat trauma, as measured retrospectively by the Dissociative Experiences Questionnaire (mean=1 1 .5, SD=1 .6) than non-PTSD patients (mean=1 .8, SD=2.1). Conclusions: Dissociative symptoms are an important element ofthe long-term psychopathological response to trauma. (Am J Psychiatry 1992; 149:328-332)
TL;DR: The effect of processing load on event-related brain potentials (ERPs) was investigated in an intermodal selective attention task in which subjects attended selectively to auditory or visual stimuli.
TL;DR: In this article, the authors reviewed their experience with 43 cases of bacterial spinal epidural abscess, as well as previously reported series of cases, and found a striking male predominance of the disease, accounting for 86% of cases.
TL;DR: The results suggest that further development of the (-)-Beta-enantiomer of FTC is warranted as an antiviral agent for infections caused by human immunodeficiency viruses.
Abstract: 2',3'-Dideoxy-5-fluoro-3'-thiacytidine (FTC) has been shown to be a potent and selective compound against human immunodeficiency virus type 1 in acutely infected primary human lymphocytes. FTC is also active against human immunodeficiency virus type 2, simian immunodeficiency virus, and feline immunodeficiency virus in various cell culture systems, including human monocytes. The antiviral activity can be prevented by 2'-deoxycytidine, but not by other natural nucleosides, suggesting that FTC must be phosphorylated to be active and 2'-deoxycytidine kinase is responsible for the phosphorylation. By using chiral columns or enzymatic techniques, the two enantiomers of FTC were separated. The (-)-beta-enantiomer of FTC was about 20-fold more potent than the (+)-beta-enantiomer against human immunodeficiency virus type 1 in peripheral blood mononuclear cells and was also effective in thymidine kinase-deficient CEM cells. Racemic FTC and its enantiomers were nontoxic to human lymphocytes and other cell lines at concentrations of up to 100 microM. Studies with human bone marrow cells indicated that racemic FTC and its (-)-enantiomer had a median inhibitory concentration of > 30 microM. The (+)-enantiomer was significantly more toxic than the (-)-enantiomer to myeloid progenitor cells. The susceptibilities to FTC of pretherapy isolates in comparison with those of posttherapy 3'-azido-3'-deoxythymidine-resistant viruses in human lymphocytes were not substantially different. Similar results were obtained with well-defined 2',3'-dideoxyinosine- and nevirapine-resistant viruses. (-)-FTC-5'-triphosphate competitively inhibited human immunodeficiency virus type 1 reverse transcriptase, with an inhibition constant of 2.9 microM, when a poly(I)n.oligo(dC)19-24 template primer was used. These results suggest that further development of the (-)-Beta-enantiomer of FTC is warranted as an antiviral agent for infections caused by human immunodeficiency viruses.