Baroreflex deficit blunts exercise training‐induced cardiovascular and autonomic adaptations in hypertensive rats

1. Baroreceptors regulate moment‐to‐moment blood pressure (BP) variations, but their long‐term effect on the cardiovascular system remains unclear. Baroreceptor deficit accompanying hypertension contributes to increased BP variability (BPV) and sympathetic activity, whereas exercise training has been associated with an improvement in these baroreflex‐mediated changes. The aim of the present study was to evaluate the autonomic, haemodynamic and cardiac morphofunctional effects of long‐term sinoaortic baroreceptor denervation (SAD) in trained and sedentary spontaneously hypertensive rats (SHR). 2. Rats were subjected to SAD or sham surgery and were then further divided into sedentary and trained groups. Exercise training was performed on a treadmill (five times per week, 50–70% maximal running speed). All groups were studied after 10 weeks. 3. Sinoaortic baroreceptor denervation in SHR had no effect on basal heart rate (HR) or BP, but did augment BPV, impairing the cardiac function associated with increased cardiac hypertrophy and collagen deposition. Exercise training reduced BP and HR, re‐established baroreflex sensitivity and improved both HR variability and BPV. However, SAD in trained SHR blunted all these improvements. Moreover, the systolic and diastolic hypertensive dysfunction, reduced left ventricular chamber diameter and increased cardiac collagen deposition seen in SHR were improved after the training protocol. These benefits were attenuated in trained SAD SHR. 4. In conclusion, the present study has demonstrated that the arterial baroreflex mediates cardiac disturbances associated with hypertension and is crucial for the beneficial cardiovascular morphofunctional and autonomic adaptations induced by chronic exercise in hypertension.     

Rapid diagnosis of the cause of pneumoperitoneum in ventilated asthmatic children

Two asthmatic children developed a pneumoperitoneum whilst being mechanically ventilated. A quick and accurate diagnosis as to the cause of the pneumoperitoneum was made by analysing the partial pressure of oxygen in the intraperitoneal free gas. This analysis helped to diagnose an intestinal perforation in one child and an air leak from lung barotrauma in the other. There was minimal delay in the surgical treatment of the child with intestinal perforation and in the other, an unnecessary laparotomy was avoided.     

Alpha-1-antitrypsin deficiency presenting as a bleeding diathesis in the newborn

Three cases of alpha-1-antitrypsin deficiency are reported. Each infant presented in the newborn period with a haemorrhagic tendency which responded to vitamin K. Two of them subsequently developed cirrhosis, and Case 2 is one of the few reported cases in infantile cirrhosis associated with the heterozygous protease inhibitor (Pi) SZ phenotype. On the basis of these 3 patients we feel that the exclusion of alpha-1-antitrypsin deficiency by Pi phenotyping should be considered in any baby presenting with a bleeding diathesis, especially in view of the genetic implications of the homozygous Pi ZZ phenotype.     

Fibroblast growth factor receptor expression reflects cellular differentiation in human oral squamous carcinoma cell lines

This study examined the expression of fibroblast growth factor receptor 2 (FGFR 2) splice variants, IIIb and IIIc, in normal and malignant human oral keratinocytes and in normal oral fibroblasts by RT-PCR using both exon-specific primers and primers common to both FGFR 2 isoforms. Fibroblasts expressed exclusively FGFR 2/IIIc whilst the normal and malignant keratinocytes co-expressed FGFR 2/IIIb and FGFR 2/IIIc. Well- differentiated keratinocytes expressed proportionally more FGFR 2/IIIb than IIIc whereas the poorly-differentiated cells expressed more FGFR 2/IIIc than IIIb. The normal and malignant keratinocytes, but not fibroblasts, expressed an additional amplification product, which consisted of both IIIb and IIIc of FGFR 2 joined by an extra base pair and with the intronic sequence removed. The results indicate that the expression of FGFR 2 isoforms reflects the degree of cellular differentiation in normal and malignant human oral keratinocytes and that receptor complexes of FGFR 2/IIIb and IIIc may regulate ligand- receptor interactions.      

Accuracy of central venous pressure measurements in the inferior vena cava in the ventilated child

Murdoch IA, Rosenthal E, Huggon IC, Coutinho W, Qureshi SA. Accuracy of central venous pressure measurements in the inferior vena cava in the ventilated child. Acta Pædiatr 1994;83:512–14. Stockholm. ISSN 0803–5253
We compared central venous pressure measurements from three sites, superior vena cava, inferior vena cava and right atrium, in 12 children undergoing cardiac catheterization whilst on assisted ventilation. There was no significant difference between the mean pressures in the superior vena cava and the inferior vena cava. Furthermore, there was also no difference between the mean pressures in the inferior vena cava and the right atrium. Because of the greater safety of the placement of pressure monitoring lines in the inferior vena cava via the femoral vein, this approach should be the preferred route for central venous pressure monitoring in children.     

Anorexia nervosa: who sees the patients and who do the patients see?

Two samples of patients with DSM-III-R anorexia nervosa, one identified by screening of a total population cohort and the other a mixed screening and referral group, were contrasted with a comparison group of sex-, age- and school-matched individuals. The rates and types of services consulted and treatment given were analyzed. The groups with anorexia nervosa tended to differ somewhat in these respects, although the numbers were too small for meaningful statistical calculations to be made. Only half of the total population sample had ever received any treatment for the eating disorder, even many years after anorexia nervosa onset in the teenage period. The implications of these findings are discussed both in terms of clinical needs and as they relate to previous research in anorexia nervosa, which has almost exclusively referred to non-population-based groups of patient.     

Functional and phenotypic characterization of peptide-vaccine-induced HCV-specific CD8+ T cells in healthy individuals and chronic hepatitis C patients

Only very limited information on phenotype and function of vaccine-induced CD8+ T cells is available for humans. We investigated hepatitis C virus-specific CD8+ T cells after vaccination with the HCV peptide-vaccine IC41 which includes 5 MHC-class I and 3 MHC class-II-restricted epitopes. In healthy subjects, IC41 induced both HCV-specific central memory as well as effector CD8+ T cells which rapidly expanded upon antigen exposure in vitro. IFNgamma production was dependent on formulation of the synthetic peptides with the adjuvant poly-l-arginine. In chronic HCV patients, the frequency of HCV-specific CD8+ T cells increased after vaccination with a decline of CD45RA-positive effector memory cells in some but not all patients. Thus, this study suggests that HCV-specific memory cells can be induced by peptide vaccination and that a reversion of functional impaired phenotypes by therapeutic vaccination is possible in chronic HCV infection.