Association of carotid arterial distensibility with Doppler indices of left ventricular filling in 50-year-old subjects

Doppler indices of left ventricular diastolic filling are associated with various cardiac and extracardiac factors. Afterload is one of the extracardiac factors influencing left ventricular diastolic filling. The distensibility of the great arteries is one of the components of afterload. In this study, the relation between Doppler indices of left ventricular filling and the distensibility of the common carotid arteries was investigated. We studied 237 subjects at 50 years of age with Doppler echocardiography and ultrasound examination of the common carotid arteries. The following Doppler indices of left ventricular filling were studied: peak early diastolic velocity E-wave, peak atrial diastolic velocity A-wave and early to atrial peak velocity ratio, E/A. Carotid arterial characteristics were: distensibility coefficient, carotid arterial diameter change in systole and fractional change in the carotid arterial diameter. The relation between Doppler indices of left ventricular filling and carotid arterial characteristics was assessed by univariate and multivariate regression analysis. There was a significant univariate, positive association between E/A ratio and carotid arterial distensibility (r = 0·27, P<0·001), carotid arterial systolic diameter change (r = 0·19, P<0·005) and fractional change of the carotid arterial diameter (r = 0·20, P<0·005). In multivariate analysis, E/A ratio was independently associated with carotid arterial distensibility (P<0·005), after adjusting for heart rate, body mass index and gender. Decreased carotid arterial distensibility was associated with a reduction in E/A ratio, suggesting that arterial distensibility may have an effect on left ventricular diastolic filling or that changes in the arterial elastic properties are associated with corresponding structural changes in the left ventricle.     

DNA viruses in the pathogenesis of sporadic chronic idiopathic intestinal pseudo-obstruction.

BACKGROUND: Hereditary forms of chronic idiopathic intestinal pseudo-obstruction (CIIP) are well described but the aetiology of most cases of sporadic CIIP is unknown. AIM: To determines whether herpes viruses can persist in the gastrointestinal tract, thereby implicating them in the pathogenesis of CIIP. METHODS: Twenty one specimens of small and large intestine from 13 patients with CIIP (eight visceral myopathy, three visceral neuropathy, two undifferentiated), and 12 patients operated on for colorectal cancer (controls) were examined for evidence of Herpesvirus DNA (cytomegalovirus, Epstein-Barr virus (EBV), herpes simplex virus type 1, and varicella zoster virus) by nested polymerase chain reaction (PCR) and in situ DNA hybridisation (ISH) to localise signal to the muscularis propria or myenteric plexus. RESULTS: Screening with nested PCR produced three patients with positive results. One patient with an inflammatory visceral neuropathy had EBV detected in the small intestine by PCR, and ISH demonstrated localisation to neurones in the myenteric plexus. A patient with a visceral myopathy had EBV DNA in both the small and large intestine; and one patient with a visceral neuropathy had small intestine positive for CMV DNA (both negative by ISH). No control tissue was positive for any virus. CONCLUSIONS: In individual patients there appears to be evidence linking a viral aetiology to sporadic CIIP. The role of neurotropic viruses in acute and chronic motility disturbances needs further study.     

Early parasympathetic neuropathy associated with elevated fasting plasma C-peptide concentrations and late parasympathetic neuropathy with hyperglycaemia and other microvascular complications.

AIMS: To examine the relationship between parasympathetic neuropathy, hyperinsulinaemia, glycaemic control (HbA(1c)), and future diabetic complications. METHODS: We assessed parasympathetic nerve function [expiration/inspiration (E/I) ratio], glomerular filtration rate (GFR), glycaemic control (HbA(1c)), fasting plasma (f-p-) C-peptide in 82 Type 2 diabetic patients (age 61 +/- 1 years) 5 and 12-15 years after diagnosis. Diabetic retinopathy was assessed 15 years after diagnosis. RESULTS: High HbA(1c) values in the first study were associated with retinopathy (with 8.6 +/- 2.0 vs. without retinopathy 6.2 +/- 1.9%; P < 0.0001) and disturbed parasympathetic nerve function (low E/I ratio; r(s) = -0.41; P = 0.0061) in the second study, as well as with deteriorations in GFR between the first and second study (r(s) = 0.62; P < 0.0001). Patients with parasympathetic neuropathy in the first study had significantly higher f-p-C-peptide concentrations than those without 3 years (1.20 +/- 0.43 vs. 0.86 +/- 0.40 nmol/l; P = 0.0015) and 5 years (1.20 +/- 0.44 vs. 0.82 +/- 0.33 nmol/l; P < 0.0001), but not 15 years after diagnosis. CONCLUSION: High HbA(1c) values 5 years after diagnosis of Type 2 diabetes were associated with retinopathy, disturbed parasympathetic nerve function, and deterioration in GFR 7-10 years later. Parasympathetic neuropathy 5 years after diagnosis was associated with high C-peptide concentrations. Parasympathetic nerve function has to be considered when beta-cell function is evaluated. Hyperglycaemia is an important factor for the development of complications in Type 2 diabetes.     

Comparison of enzyme-linked immunosorbent assay, radioimmunoassay, complement fixation, anticomplement immunofluorescence and passive haemagglutination techniques for detecting cytomegalovirus IgG antibody.

The radioimmunoassay (RIA) and enzyme-linked immunosorbent assay (ELISA) techniques were found to be comparable in sensitivity and specificity for detecting cytomegalovirus IgG antibody, and 10 to 100 times more sensitive than complement-fixation (CF), anticomplement immunofluorescence (ACIF) and passive haemagglutination (PHA). In screening tests for antibody, the frequency of false-positive and -negative results was 0.6% for RIA and ELISA, 1.5% for CF, 1.6% for ACIF and 3.6% for PHA. PHA was the least satisfactory test, largely because of technical problems. Cytomegalovirus (CMV) infection is an important cause of congenital brain damage and is also a major complication of both prolonged immunosuppressive therapy, especially in patients with organ transplants, and multi-donor blood transfusions. For serological diagnosis of infection, as well as for screening for antibody in patients and in blood donors, the solid-phase indirect radioimmunoassay (RIA) and enzyme-linked immunosorbent assay (ELISA) techniques offer distinct improvements in sensitivity over previous methods. Although the principle of both tests, based on the detection of antigen-antibody reactions by means of a labelled anti-antibody, is the same, each possesses its own particular technical advantages and disadvantages, and both require their own expensive equipment for the reading of the results. There is still a lack of data on how they compare in sensitivity and specificity. The present study was undertaken to compare the two methods for the detection of CMV IgG and to evaluate them against the older techniques of complement-fixation (CF), passive haemagglutination (PHA) and anticomplement immunofluorescence (ACIF).     

Comparison of radioimmunoassay and the gel filtration technique for routine diagnosis of rubella during pregnancy.

Radioimmunoassay (RIA) for rubella-specific IgM antibodies was compared with haemagglutination-inhibition (HI) in conjunction with gel filtration for the diagnosis of rubella infection in pregnant women during a 1-year period. In total 476 women were investigated of whom 221 were tested for rubella IgM. Both techniques gave positive results with 64 sera, and RIA alone with one additional serum. Difficulties associated with the removal of non-specific HI activity were encountered with four sera all of which were negative by RIA. RIA was found to have practical advantages over the gel filtration method but is at present technically more difficult to perform.     

Antibody responses in recipients of varicella vaccine assayed by immunoblotting

Sera taken from 35 children with cancer who had been vaccinated with live varicella vaccine were assayed using immunoblotting for the presence of IgG class antibodies to proteins present in varicella-zoster virus (VZV)-infected cells. Sera from 23 of these patients were also assayed for IgM class antibodies. The patterns of immunoreactivity observed for these patients following vaccination were substantially weaker and more variable than those detected following natural VZV infection in otherwise healthy individuals. The IgG responses detected following vaccination involved up to 10 protein bands between 28 and 188 kDa. Bands were particularly frequent in the 78–96 kDa region. IgM responses involved up to 10 bands between 28 and 114 kDa, with the bands in the 78–96 kDa region and at 32–36 kDa being detected most frequently. Repeated vaccination generally produced a stronger IgG antibody response than did single vaccination, and subsequent exposure of vaccinees to natural VZV infection resulted in an increased level of reactivity for IgG antibodies, but not for IgM. Similar reaction patterns were obtained with sera from vaccinees when the vaccine virus and wild-type VZV were used as antigens. Immunoblotting showed good correlation with indirect radioimmunoassay for the detection of a vaccine-induced IgG response.     

An echocardiographic study of right and left ventricular adaptation to physical exercise in elite female orienteers.

BACKGROUND: A considerable body of echocardiographic studies has described how athletic training induces morphological adaptation of the left ventricle in male endurance athletes, but only a few studies have described left ventricular adaptation in female endurance athletes. In contrast to changes in the left ventricle far less attention has been directed towards right ventricular changes due to extensive physical exercise. The purpose of this study was to obtain normal values and to determine if there are any differences in right and left ventricular cavity and wall dimensions between female orienteers and females with a mainly sedentary lifestyle. METHODS: Echocardiography was performed in 42 highly trained elite female orienteers and 32 healthy female students with a predominantly sedentary lifestyle. The 74 females had no history of cardiac disease, a normal electrocardiogram and showed no echocardiographic abnormalities. M-mode and two-dimensional measurements of the right and left ventricular cavity and wall were obtained in elite orienteers and sedentary females. For the right ventricle and wall, multiple cross-sections were used and measurements were obtained from the right ventricular inflow and outflow tract. RESULTS: The left ventricular end-diastolic cavity dimension and the left ventricular wall thickness were significantly greater in the athletes compared with the sedentary controls. The right ventricular inflow tract measurements were all significantly greater in the orienteers compared with the controls but the right ventricular outflow tract measurements were comparable in the study groups. The right ventricular wall thickness, calculated as the mean of three different wall measurements was an average of 13% greater in the athletes compared with the sedentary controls. CONCLUSION: This study suggests symmetrical cardiac enlargement with a concomitant increase in both the right and left ventricular wall, probably reflecting the increased haemodynamic loading in the female athletes.     

A 14-year prospective study of autonomic nerve function in Type 1 diabetic patients: association with nephropathy.

AIMS: Prospective studies of autonomic nerve function are rare. We have followed the progression of autonomic dysfunction in relation to nephropathy over 14 years in Type 1 diabetic patients. METHODS: Autonomic nerve function was assessed by heart-rate responses to deep breathing (E/I ratio) and tilting (acceleration and brake indices) and by the postural blood pressure reaction in 58 patients, 43 of whom were reassessed after 14 years. Nephropathy was evaluated by the degree of albuminuria (albuminuria > 20 micro g/min or > 0.03 g/24 h) and glomerular filtration rate ((51)Cr-EDTA plasma clearance). The acceleration index had deteriorated after 7 years (P = 0.0155), whereas the E/I ratio (P = 0.0070) and the diastolic postural blood pressure reaction (P = 0.0054) had deteriorated 14 years after the baseline examination (age-corrected values). All those with albuminuria at the third examination showed signs of autonomic neuropathy at baseline (10 of 10) compared with only nine of 22 without (P = 0.0016). Multiple regression analysis showed that the association between autonomic dysfunction and future albuminuria was due to the E/I ratio. In addition, individuals with an abnormal postural diastolic blood pressure fall (n = 7) at baseline showed a greater fall in glomerular filtration rate more than others 7-14 years later [29 (16.5) ml/min/1.72 m(2) vs. 11 (9) ml/min/1.72 m(2); P = 0.0074]. CONCLUSION: Autonomic nerve function had deteriorated after 14 years. Autonomic neuropathy and abnormal postural diastolic blood pressure falls at baseline were associated with future renal complications.