Renal denervation abolishes hypertension in low-birth-weight offspring from pregnant rats with reduced uterine perfusion

Low birth weight is a risk factor for the subsequent development of hypertension in humans. We previously reported that reduced uterine perfusion in the pregnant rat results in growth-restricted offspring predisposed to the development of hypertension. The purpose of this study was to determine whether the sympathetic nervous system plays a role in mediating hypertension in this model of low birth weight. Weight at birth was significantly decreased in male growth-restricted offspring (5.9+/-0.1 grams) as compared with male control offspring (6.5+/-0.2 grams; P<0.05). At 10 weeks of age, growth-restricted offspring and control offspring were randomly assigned to either an intact group (sham-denervated) or a group subjected to bilateral renal denervation. For sham-denervated offspring, mean arterial pressure was significantly elevated in growth-restricted offspring (145+/-4 mm Hg; n=7) as compared with control offspring (134+/-3 mm Hg; P<0.05; n=9) at 12 weeks of age. Bilateral renal denervation resulted in a marked reduction in arterial pressure in growth-restricted offspring (125+/-3 mm Hg; P<0.01; difference of 20 mm Hg versus sham growth-restricted; n=8) but no significant decrease in control offspring (127+/-3 mm Hg; difference of 7 mm Hg versus sham control; n=9). Adequacy of renal denervation was verified by >90% reduction in renal norepinephrine content. Therefore, these findings indicate the renal nerves play an important role in mediating hypertension in adult growth-restricted offspring.     

Intensive care unit readmission after elective coronary artery bypass grafting

Prospective data of 3,120 consecutive patients who had elective coronary artery bypass were analyzed to identify patient profile, cost, outcome and predictors of those readmitted to the intensive care unit. Group A (n=3,002) had a single intensive care unit admission and group B (n=118) were readmitted within 30 days after surgery. Parsonnet score, EuroSCORE, age, body mass index, chronic obstructive airway disease, peripheral vascular disease, renal dysfunction, unstable angina, congestive cardiac failure, and poor left ventricular function were higher in group B. Bypass and crossclamp times were longer, and the prevalence of inotropic and balloon pump support, arrhythmias, myocardial infarction, re-exploration, blood loss and transfusion, cerebrovascular accident, wound infection, sternal dehiscence, and multisystem failure were higher in group B. Despite a 4-fold increase in cost of care, the mortality rate (32.4%) of patients readmitted to intensive care was 23-times higher than routine patients (1.4%). Crossclamp time>80 min, Parsonnet score>10, EuroSCORE>9, sternal dehiscence, ventricular arrhythmias, and renal failure predicted readmission.     

Issues with care in the elderly patient presenting with acute ischemia

The issues surrounding care of the elderly patient with acute coronary syndromes (ACS) present significant challenges to clinicians and investigators. The elderly often have atypical symptoms of acute ischemia, have greater medical comorbidities, and are more likely to die from ischemic heart disease. Important differences exist among elderly patients with ACS as compared with their younger counterparts, including age-related changes in physiology, metabolism of drugs, and overall functional status, all of which influence treatment patterns and clinical outcomes. Given the absence of elderly patients in many clinical trials, these high-risk individuals are sometimes managed with more conservative strategies, which at times diverge from accepted guidelines. This review addresses clinically important issues in the care of elderly patients with acute ischemia and highlights recent studies that provide new insight into this complex area of cardiovascular care.     

Comparison of myeloma cell contamination of bone marrow and peripheral blood stem cell harvests

It could be speculated for patients with myeloma and other lymphoproliferative disorders that peripheral blood stem cells may be preferable to bone marrow for autologous transplantation because they may be less contaminated by neoplastic cells. To test this possibility, the immunoglobulin heavy chain gene rearrangement and limiting dilution polymerase chain reaction were used to sensitively quantify myeloma cells in bone marrow and peripheral blood stem cell collections, taken at a similar time, from eight patients with multiple myeloma. Levels of residual disease in the peripheral blood stem cell harvests were variable and did not reflect the tumour burden in the marrow. Peripheral blood stem cells contained 1.7 to 23 700-fold fewer myeloma cells compared with the bone marrow and would have resulted in reinfusion of 0.08 to 59 480-fold fewer myeloma cells based on total reinfused CFU-GM and 0.24 to 24 700-fold fewer myeloma cells based on total reinfused nucleated cells. Assuming that the proportion of clonogenic myeloma cells is equivalent, peripheral blood stem cells may be better than bone marrow as a source of haemopoietic stem cells for transplantation in multiple myeloma. The clinical follow-up suggested that patients transplanted with peripheral blood stem cells containing a low number of myeloma cells had better disease control than those transplanted with peripheral blood stem cells containing a high number.     

Viral infections in childhood leukemia

The importance of viral infections in 150 children receiving therapy for leukemia was studied prospectively by application of comprehensive viral diagnostic procedures. One hundred five viral infections were identified, with herpes simplex virus and varicella-zoster virus being the most common agents. The spectrum of viruses associated with serious illness was wider than that in previous studies, and adenoviruses, parainfluenza viruses, rhinoviruses, and enteroviruses were important causes of morbidity. Viral isolation was the most sensitive diagnostic procedure used because complement fixation serology was falsely negative in two-thirds of cases. The occurrence of viral infection may be a previously overlooked important cause of respiratory tract infection and acute pyrexia of unknown origin. Viral infection rates were highest in patients with acute myeloblastic leukemia, in induction and relapse, and in patients treated with newer chemotherapeutic schedules. Thus, viruses are important pathogens in children with leukemia.     

Regional adiposity patterns in relation to lipids, lipoprotein cholesterol, and lipoprotein subfraction mass in men

Anatomical adipose tissue distribution patterns are reported to relate to plasma lipids and risk of cardiovascular disease. Waist to hip girth ratios (WHR) and subscapular 10 triceps skinfold thickness ratios (STR) were compared with percent body fat and body mass index values as correlates of plasma lipids and lipoprotein cholesterol and serum lipoprotein subfraction mass by analytic ultracentrifugation in 81 sedentary middle-aged men in a typical range of adiposity. WHR was significantly and positively correlated with plasma concentrations of triglycerides, cholesterol, and low and very low density lipoprotein (LDL and VLDL) cholesterol and inversely correlated with high density lipoprotein (HDL) cholesterol. STR followed these trends, though less strongly, in relation to plasma triglycerides, VLDL cholesterol, and HDL cholesterol. Pronounced differences were found between regional adiposity patterns in their relationships to lipoprotein subfractions, as determined by analytic ultracentrifugation. WHR was negatively correlated with HDL2 (flotation rate F(1.2) 3.5-9), positively with small LDL (S.f 0-7), intermediate density lipoprotein (S.f 12-20), and VLDL (S.f 20-400), while STR correlated with larger LDL (S.f 7-12) and larger VLDL (S.f 60-400). Overall adiposity was not significantly associated with plasma lipoprotein levels after adjusting for regional adiposity patterns. Plasma sex hormone-binding globulin and percent free testosterone were associated with regional adiposity, but did not account for the correlations between WHR and lipoproteins. WHR and STR are measures of fat distribution that correlate with plasma lipoprotein profiles consistent with cardiovascular disease risk and have different relationships to lipoprotein mass subfractions.     

The effect of weight loss by dieting or exercise on resting metabolic rate in overweight men

While resting metabolic rate (RMR) is known to decline during periods of energy restriction, the effect of exercise training during weight loss on RMR is less clear. We studied separately the effect of energy restriction and exercise training on weight loss and RMR in a one-year randomized, controlled trial. One hundred twenty-one overweight, sedentary men (age 30-59) who were randomly assigned to a control (C), energy restriction only (D), or exercise only (E) group were examined at baseline and after one year for changes in RMR as measured by standard indirect calorimetry. Relative to controls, E increased fitness and jogged an average of 9.97 +/- 5.6 miles/week and did not change energy intake while D significantly reduced energy consumption. Both groups achieved significant weight loss and fat mass loss when compared to the controls at the end of one year. After one year, the D group showed a small yet significant decline in RMR (kcal/h and kcal/FFM/h) when compared to controls and exercisers, while the E group showed no significant changes. Therefore, in moderately overweight men, a one-year program of weight loss by energy restriction produced a significant decline in RMR while weight loss by exercise did not change RMR.