Intimacy of the neuroeffector junction and resistance to α-adrenoceptor-blockade of the neurogenic contractile response in vasa deferentia from guinea pig and rat

The effect of phentolamine on the neurogenic contractile response in vasa deferentia from rat and guniea pig was studied during Wallerian degeneration. This response was also investigated after partial denervation (surgery or chemical sympathectomy by guanethidine treatment) in vasa deferentia from guinea pig. During Wallerian degeneration the response showed a gradual increase in sensitivity to phentolamine and was abolished in the late stages. The neurogenic contractile response of the partially denervated vas deferens was blocked by low concentrations of phentolamine. It is concluded that decreased intimacy of the neuroeffector junctions leads to increased susceptibility to α-adrenoceptor blockade of the contractile response to nerve stimulation. It is further concluded that the motortransmission in the vas deferens is essentially adrenergic. The resistance to α-adrenoceptor blockade of the initial phase of the contractile response to nerve stimulation of intact vasa deferentia from guinea pig and rat might well be explained by the “proximity theory” of Dale & Gaddum although participation of supplementary mediators cannot be excluded.     

Female sex as a risk factor for stroke in atrial fibrillation: a nationwide cohort study

Summary. Background: Female sex has been suggested as a risk factor for stroke/thromboembolism in patients with non‐valvular atrial fibrillation (AF) and has therefore been included within risk scores, e.g. the CHA₂DS₂‐VASc score, and guidelines. Objectives: To investigate the risk of stroke/thromboembolism associated with female sex in non‐valvular AF patients. Patients/Methods: Using the national Danish registers, we identified non‐anticoagulated patients discharged with non‐valvular AF (1997–2008), and subdivided the population into three age intervals: < 65, 65–74 and ≥ 75 years. We calculated stroke rates according to sex, and assessed the stroke risk associated with female sex by using Cox regression analysis. Results: We included 87 202 AF patients, and 44 744 (51.3%) were female. The rate of stroke/thromboembolism for females aged < 65 and 65–74 years was not increased as compared with men, whereas the rate for females aged ≥ 75 years was increased. At both 1‐year and 12‐year follow‐up, female sex did not increase the risk of stroke for patients aged < 75 years. At 1‐year follow‐up, the hazard ratios associated with female sex were 0.89 (95% confidence interval [CI] 0.70–1.13) and 0.91 (95 CI 0.79–1.05) for patients aged < 65 and 65–74 years, respectively, and being female and aged ≥ 75 years was associated with an increased risk of stroke of 1.20 (95 CI 1.12–1.28). Conclusion: Female sex was only associated with an increased risk of stroke for AF patients aged ≥ 75 years. Our study suggests that female sex should not be automatically included as an independent stroke/thromboembolic risk factor in guidelines or in the CHA₂DS₂‐VASc score, without careful prior consideration of the ‘age < 65 and lone AF’ criterion.     

Inactivation of the rhlA gene in Pseudomonas aeruginosa prevents rhamnolipid production,disabling the protection against polymorphonuclear leukocytes

Many of the virulence factors produced by the opportunistic human pathogen Pseudomonas aeruginosa are quorum‐sensing (QS) regulated. Among these are rhamnolipids, which have been shown to cause lysis of several cellular components of the human immune system, e.g. monocyte‐derived macrophages and polymorphonuclear leukocytes (PMNs). We have previously shown that rhamnolipids produced by P. aeruginosa cause necrotic death of PMNs in vitro. This raises the possibility that rhamnolipids may function as a ‘biofilm shield’in vivo, which contributes significantly to the increased tolerance of P. aeruginosa biofilms to PMNs. In the present study, we demonstrate the importance of the production of rhamnolipids in the establishment and persistence of P. aeruginosa infections, using an in vitro biofilm system, an intraperitoneal foreign‐body model and a pulmonary model of P. aeruginosa infections in mice. Our experimental data showed that a P. aeruginosa strain, unable to produce any detectable rhamnolipids due to an inactivating mutation in the single QS‐controlled rhlA gene, did not induce necrosis of PMNs in vitro and exhibited increased clearance compared with its wild‐type counterpart in vivo. Conclusively, the results support our model that rhamnolipids are key protective agents of P. aeruginosa against PMNs.     

MORTALITY AND LIFE-TABLE IN DOWN'S SYNDROME

ABSTRACT: Øster, J., Mikkelsen, M. and Nielsen, A. (Department of Paediatrics, Randers Centralsygehus, Randers, John F. Kennedy Institute, Glostrup, and the Institute for Human Genetics, University of Copenhagen, Denmark). Mortality and life-table in Down's syndrome. Acta Paediatr Scand, 64:322, 1975.–The causes of death in 130 patients with Down's Syndrome and mortality rates from a material of 524 patients were tabulated; a life-table for the ages over 5 years was constructed. An overall death rate of 5–7 times the general population rate was found. No sex difference was observed. The excess mortality was especially high for heart disease and respiratory disease. Also infectious diseases, others than pneumonia and tuberculosis, showed high mortality rates.     

Defective Leukocyte Interferon Response in Children with Recurrent Infections Accompanied by Arthralgia

ABSTRACT. Children with recurrent and/or unusually severe infections were investigated for possible defects in the interferon (IFN)-natural killer (NK) cell system. Two series, each of 13 children, were examined, one in 1982 and one in 1983. Healthy children, seven in 1982 and eight in 1983, served as controls. Peripheral blood mononuclear leukocytes were examined for IFN production induced by the IFN-α inducers Sendai virus and Escherichia coli and by the IFN-γ inducers Concanavalin A and Lens culinaris lectin. None of these inducers discriminated patients from controls. However, the bacteria Staphylococcus aureus Cowan I (SACol), inducers of atypical IFN in null lymphocytes, yielded significantly lower IFN production in infection-prone children than in controls, particularly in children with recurrent infections accompanied by arthralgia. No differences in basal NK activity or in the in vitro enhancement of such activity by IFN-α were found between patients and controls.     

COMPARISON BETWEEN MIDAZOLAM AND THIOPENTONE-BASED BALANCED ANAESTHESIA FOR DAY-CASE SURGERY

In a randomized study of 100 women (ASA 1–2) undergoingtermination of pregnancy as outpatients, the combination ofmidazolam-fentanyl-nitrous oxide was compared with thiopentone-fentanyl—nitrousoxide. The induction time (the time recorded until disappearanceof the palpebral reflex) was significantly longer in the midazolamgroup (40 s) than in the thiopentone group (31 s). There wereno significant differences in heart rate or arterial pressurebetween the two groups. Thirty minutes after the terminationof surgery the degree of awareness., estimated by means of GlasgowComa Scale, was lower in the midazolam group. After 60 and 180min the scores were equal. During recovery more patients experiencedside-effects in the thiopentone group than in the midazolamgroup, the difference being statistically significant 72 h afterdischarge when 66% and 34% of the patients complained of side-effects,respectively. Midazolam is as suitable as thiopentone for theinduction of anaesthesia in day-case surgery.     

Health status and health behaviour in men and women at the age of 34 years

The aim of this investigation was to study relationships betweenhealth status and health behaviour in men and women. A groupof 425 Swedish students were randomly selected in 1974 at theage of 16 years. In 1992, at the age of 34 years, those whowere investigated comprised 88% of the original sample. Cross-sectionaldata on health status and health behaviour were obtained througha self-administered questionnaire. Among the men, leisure-timephysical activity, smoking cigarettes and use of smokeless tobaccowere significantly associated with perceived health, diseaseand perceived health, and impaired musculoskeletal functionrespectively. Among the women walking/cycling to work and choosinghealthy foods significantly decreased the likelihood of impairedmusculoskeletal function and being overweight respectively.