Research on bronchomotor properties of a calcium inhibitor (bepridil) in asthmatic patients

The bronchomotor properties of calcium antagonists were investigated in 10 patients with paroxysmal asthma, using a double-blind, cross-over method. Each patient received, in random order, either a placebo (5% glucose solution) or bepridil (2 mg/kg) administered by intravenous infusion over 30 min. There were no changes in mean values of vital capacity, FEV1 and systolic blood pressure. Bradycardia was regularly present. Diastolic blood pressure was lowered in 4 patients. An analysis of individual responses showed that FEV1 was unimpaired in 9 patients and was increased by more than 25% in one case. Thus, contrary to beta-blockers, bepridil and other calcium antagonists have no adverse effects on the bronchi of asthmatics; on the other hand, their bronchorelaxant effect is too inconstant for these drugs to be used in the symptomatic treatment of paroxysmal asthma.     

Tripartite interactions between tsetse flies,Sodalis glossinidius and trypanosomes—An epidemiological approach in two historical human African trypanosomiasis foci in Cameroon

Epidemiological surveys were conducted in two historical human African trypanosomiasis foci in South Cameroon, Bipindi and Campo. In each focus, three sampling areas were defined. In Bipindi, only Glossina palpalis was identified, whereas four species were identified in Campo, G. palpalis being highly predominant (93%). For further analyses, 75 flies were randomly chosen among the flies trapped in each of the six villages. Large and statistically significant differences were recorded between both (1) the prevalence of Sodalis glossinidius (tsetse symbiont) and the prevalence of trypanosome infection of the major fly species G. p. palpalis and (2) the respective prevalence of symbiont and infection between the two foci. Despite these differences, the rate of infected flies harbouring the symbiont was very similar (75%) in both foci, suggesting that symbionts favour fly infection by trypanosomes. This hypothesis was statistically tested and assessed, showing that S. glossinidius is potentially an efficient target for controlling tsetse fly vectorial competence and consequently sleeping sickness.     

Differential effects of passive immunization with somatostatin antiserum on adenohypophysial hormone secretions in starved rats

The role of somatostatin (SRIF) on adenohypophysial hormone secretion in starved rats was reassessed by passive immunization. Because of the absence of pulsatile GH secretion in starved rats, the effects of the injection of SRIF antiserum on GH levels can be clearly demonstrated. To determine whether starvation modifies the sensitivity of the adenohypophysis to SRIF, we measured 125I-labelled iodo-N-Tyr-SRIF binding. There was no difference in the dissociation constant (Kd) nor in the maximal binding capacity (Bmax) in fed (n = 15) and starved (n = 15) animals (Kd = 0.38 +/- 0.09 (S.E.M.) and 0.45 +/- 0.09 nmol; Bmax = 204 +/- 39 and 205 +/- 30 fmol/mg protein respectively). Administration of SRIF antiserum resulted in a dose-dependent increase in plasma concentrations of GH, TSH and prolactin. The minimal effective dose of SRIF antiserum was 50 microliters for GH, 100 microliters TSH and 200 microliter for prolactin. Our results show that: starvation does not modify adenohypophysial SRIF-binding sites, in starved male rats endogenous SRIF exerts a negative control on prolactin secretion in vivo and sensitivity to endogenous SRIF seems to be different for each hypophysial cell type.     

Effects of beta-adrenoceptors blocking eye drops in patients with chronic bronchitis.

Beta-blocker eyedrops used on asthmatic patients are known to enhance asthma which is, as chronic bronchitis, an obstructive disease of the lung, and an authentic bronchoconstriction is always possible. A single blind parallel trial in 3 groups of 10 patients with grade II and III chronic bronchitis, was conducted to evaluate the cardiovascular and bronchial tolerance of 3 beta-blocker eyedrops: timolol, betaxolol and carteolol compared to placebo. The following parameters were measured during a 90 minutes period: heart rate, systolic and diastolic blood pressure, forced expiratory volume in one second, vital capacity. It appeared that only heart rate lowers significantly under the influence of the beta-blocker eyedrop, the other parameters did not change and no difference was noticed between the three eyedrops. However, comparison of individual values showed a significant decrease of forced expiratory volume in one second in certain subjects and this, although betaxolol is a beta 1 selective beta-blocker. Caution should be taken each time beta-blocker eyedrops are prescribed for glaucoma to patients with chronic bronchitis.     

Alterations of the cerebral cortex in sporadic small vessel disease: A systematic review of in?vivo MRI data

Cerebral small vessel diseases of the brain are a major determinant of cognitive impairment in the elderly. In small vessel diseases, the most easily identifiable lesions, both at post-mortem evaluation and magnetic resonance imaging, lie in subcortical areas. However, recent results obtained post-mortem, particularly in severe cases, have highlighted the burden of cortex lesions such as microinfarcts and diffuse neuronal loss. The recent development of image post-processing methods allows now assessing in vivo multiple aspects of the cerebral cortex. This systematic review aimed to analyze in vivo magnetic resonance imaging studies evaluating cortex alterations at different stages of small vessel diseases. Studies assessing the relationships between small vessel disease magnetic resonance imaging markers obtained at the subcortical level and cortex estimates were reviewed both in community-dwelling elderly and in patients with symptomatic small vessel diseases. Thereafter, studies analyzing cortex estimates in small vessel disease patients compared with healthy subjects were evaluated. The results support that important cortex alterations develop along the course of small vessel diseases independently of concomitant neurodegenerative processes. Easy detection and quantification of cortex changes in small vessel diseases as well as understanding their underlying mechanisms are challenging tasks for better understanding cognitive decline in small vessel diseases.