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The determinants of bone mineral density (BMD) at multiple sites were examined in a fit college population. Subjects were 755 males (mean age = 18.7 years) entering the United States Military Academy. A questionnaire assessed exercise frequency and milk, caffeine, and alcohol consumption and tobacco use. Academy staff measured height, weight, and fitness. Calcaneal BMD was measured by peripheral dual-energy x-ray absorptiometry (pDXA). Peripheral-quantitative computed tomography (pQCT) was used to measure tibial mineral content, circumference and cortical thickness. Spine and hip BMD were measured by DXA in a subset (n = 159). Mean BMD at all sites was approximately one standard deviation above young normal (p < 0.05). African Americans had significantly higher hip, spine and heel BMD and greater tibial mineral content and cortical thickness than Caucasians and Asians. In Caucasians (n = 653), weight was a significant determinant of BMD at every skeletal site. Prior exercise levels and milk intake positively related to bone density and size, while caffeine had a negative impact. There was an apparent interaction between milk and exercise in BMD at the heel, spine, hip and tibial mineral content and cortical thickness. Our data confirm the importance of race, body size, milk intake and duration of weekly exercise as determinants of BMD and bone size.

We previously reported that the abl promoter (Pa) undergoes de novo DNA methylation in the course of chronic myelocytic leukemia (CML). The clinical implications of this finding are the subject of the present study in which samples of CML patients, including a group treated with interferon alpha (IFNalpha) were surveyed. The methylation status of the abl promoter was monitored by polymerase chain reaction (PCR) amplification of the Pa region after digestion with several site-methylation sensitive restriction enzymes. Some 74% of the DNA samples from blood and marrow drawn in the chronic phase were nonmethylated, similar to control samples from non-CML patients. The remaining 26% were partially methylated in the abl Pa region. The latter samples were derived from patients who were indistinguishable from the others on the basis of clinical presentation. Methylated samples were mostly derived from patients known to have a disease of longer duration (26 months v 7.5 months, P = .01). Samples of 30 IFNalpha-treated patients were sequentially analyzed in the course of treatment. Fifteen patients with no evidence of Pa methylation before treatment remained methylation-free. The remainder, who displayed Pa methylation before treatment, reverted to the methylation-free status. The outcome is attributed to IFNalpha therapy, as the Pa methylation status was not reversed in any of the patients treated with hydroxyurea. Methylation of the abl promoter indicates a disease of long-standing, most likely associated with a higher probability of imminent blastic transformation. It appears to predict the outcome of IFNalpha therapy far better than the cytogenetic response.

Unlabelled: OBJECTIVE, DESIGN AND PATIENTS: Between August 1981 and July 1983, 5839 consecutive myocardial infarction patients were hospitalized in 13 coronary care units in Israel. The present study examines 10 year survival among 4037 consecutive patients with a first myocardial infarction with either Q or non-Q waves. Demographic and medical data were collected from hospital records, and 1 year clinical follow-up was complete for 99% of hospital survivors. Mortality follow-up was extended to June 1992 (mean 10 years of follow-up)., Results: Five hundred and eighty patients (14%) had first myocardial infarctions of the non-Q wave type and 3457 of the Q wave type. Hospital mortality was significantly higher in patients with a Q wave (10%) than those with a non-Q wave myocardial infarction (7%) (P < 0.05). One year post-discharge, non-fatal reinfarction and mortality rates were comparable in patients with Q wave (4% and 7%) and non-Q wave myocardial infarctions (4% and 7% respectively). Similarly, 5 to 10 year post-discharge mortality rates were equally high in patients with a non-Q wave (26% and 44%) as in those with a first episode of a Q wave myocardial infarction (22% and 40% respectively)., Conclusions: Patients with a first non-Q wave acute myocardial infarction exhibited relatively better in-hospital survival than counterparts with a first Q wave infarction, but the advantage did not persist after discharge. Patients with a non-Q wave infarction deserve particular attention as their post-discharge mortality risk is similar to counterparts with a first Q wave myocardial infarction.

De novo methylation of CpG islands is a rare event in mammalian cells. It has been observed in the course of developmental processes, such as X chromosome inactivation and genomic imprinting. The methylation of DNA, an important factor in the epigenetic control of gene expression, may also be involved in tumorigenesis. After the t(9;22) chromosomal translocation and generation of the Philadelphia chromosome, the initiating event in chronic myelogenous leukemia (CML), most of the abl coding sequence is fused to the 5' region of the bcr gene. Expression of the hybrid bcr-abl gene is, therefore, regulated by the bcr promoter. In most cases of CML, one of the two abl promoters (Pa) is nested within the bcr-abl transcriptional unit and should be able to transcribe the type Ia 6-kb normal abl mRNA from the Philadelphia chromosome. However, we have found that the 6-kb transcript is present only in CML cell lines containing a normal abl allele and that the apparent inactivation of the nested Pa promoter is associated with allele-specific methylation. Furthermore, we have noticed that the Pa promoter is contained within a CpG island and undergoes progressive de novo methylation in the course of the disease. This is attested to by the fact that DNA samples from CML patients that are methylation-free at the time of diagnosis invariably become methylated in advanced CML. Since tumor progression in CML cannot always be inferred from the clinical presentation, assessment of de novo CpG methylation may prove to be of critical value in management of the disease. It could herald blastic transformation at a stage when bone marrow transplantation, the only potentially curative therapeutic procedure in CML, is still effective.

Background and Purpose: Stroke complicating acute myocardial infarction is associated with substantial morbidity and mortality. The purpose of this study was to assess the incidence, predictors, and impact on mortality of stroke/transient ischemic attacks occurring after hospital discharge in a large unselected population of acute myocardial infarction survivors., Methods: During a secondary prevention study with nifedipine (SPRINT), demographic, anamnestic, and clinical data were collected for 5839 consecutive acute myocardial infarction patients admitted to 13 coronary care units in Israel. Hospital survivors (n = 4808) were followed for a year after their discharge. Mortality was assessed for a mean follow-up of 5.5 years (range, 4.5 to 7 years)., Results: One percent (48/4808) of hospital survivors from acute myocardial infarction experienced a stroke/transient ischemic attack in the year after acute myocardial infarction. Thirty-one percent (15 of 48) of events occurred in the first month after hospital discharge. Incidence was higher among older patients (> 70 years; 1.9%), those with anterior site of myocardial infarction (1.35%), a previous history of myocardial infarction (1.8%), hypertension (1.4%), stroke in the past (4.1%), and chronic atrial fibrillation (9%). Multivariate analysis identified the following as independent predictors of stroke/transient ischemic attacks occurring in the year after hospital discharge: chronic atrial fibrillation, older age, history of previous myocardial infarction, anterior myocardial infarction site, serum glutamic oxaloacetic transaminase levels more than four times above upper normal limits, and stroke in the past. The age-adjusted 1-year and long-term mortality rates (4.5 to 7 years; mean, 5.5 years) were significantly higher in patients with (31% and 62%) than in those without stroke/transient ischemic attacks (9% and 31%, respectively; P < .01)., Conclusions: Stroke/transient ischemic attack is a relatively rare (1%) complication in the year after hospital discharge from acute myocardial infarction, though more frequent in the first month. Chronic atrial fibrillation, older age, anterior myocardial infarction site, serum glutamic oxaloacetic transaminase levels more than four times above upper normal limits, past myocardial infarction, and stroke identify high-risk patients. Patients suffering from subsequent stroke/transient ischemic attacks experienced higher mortality than counterparts who remained free from this complication.