Sociocognitive Factors Associated with Nonadherence to Medication After Hospital Discharge

Poor adherence to prescribed medication is a well-known problem and continues to be a major challenge in all medical specialties. Unlike previous studies that have mainly focused on nonadherence behaviors in specific diseases, this study sought to examine socio-cognitive factors associated with nonadherence behavior in a sample of a general clinical population. A questionnaire investigating socio-demographic and cognitive factors and a telephone follow-up interview were administered to 84 patients recruited in a General Medicine Unit before their discharge. Half of the participants were informed about that follow-up procedure. One month after hospital discharge, 42% of uninformed patients reported nonadherence behaviors, as against 21% of informed patients. Middle-aged patients and short-term treatments were associated significantly more often with nonadherence. Among cognitive factors, patients’ perceived risks and benefits of nonadherence, personal susceptibility to diseases, subjective health value, and reported memory failures were significantly associated with adherence. We conclude that a patient's perception may be more important than medication load, illness severity, and complexity of regimen in influencing medication adherence, and that a telephone call follow-up helps in monitoring medication adherence after hospital discharge.     

Activation of muscarinic receptors elicits inotropic responses in ventricular muscle from rats with heart failure through myosin light chain phosphorylation

Background and purpose:

Muscarinic stimulation increases myofilament Ca²⁺ sensitivity with no apparent inotropic response in normal rat myocardium. Increased myofilament Ca²⁺ sensitivity is a molecular mechanism promoting increased contractility in failing cardiac tissue. Thus, muscarinic receptor activation could elicit inotropic responses in ventricular myocardium from rats with heart failure, through increasing phosphorylation of myosin light chain (MLC).

Experimental approach:

Contractile force was measured in left ventricular papillary muscles from male Wistar rats, 6 weeks after left coronary artery ligation or sham surgery. Muscles were also frozen, and MLC-2 phosphorylation level was quantified.

Key results:

Carbachol (10 µmol·L⁻¹) evoked a positive inotropic response only in muscles from rats with heart failure approximating 36% of that elicited by 1 µmol·L⁻¹ isoproterenol (20 ± 1.5% and 56 ± 6.1% above basal respectively). Carbachol-evoked inotropic responses did not correlate with infarction size but did correlate with increased left ventricular end diastolic pressure, heart weight/body weight ratio and lung weight, primary indicators of the severity of heart failure. Only muscarinic receptor antagonists selective for M₂ receptors antagonized carbachol-mediated inotropic effects with the expected potency. Carbachol-evoked inotropic responses and increase in phosphorylated MLC-2 were attenuated by MLC kinase (ML-9) and Rho-kinase inhibition (Y-27632), and inotropic responses were abolished by Pertussis toxin pretreatment.

Conclusion and implications:

In failing ventricular muscle, muscarinic receptor activation, most likely via M₂ receptors, provides inotropic support by increasing MLC phosphorylation and consequently, myofilament Ca²⁺ sensitivity. Enhancement of myofilament Ca²⁺ sensitivity, representing a less energy-demanding mechanism of inotropic support may be particularly advantageous in failing hearts.     

Motor distal component and pragmatic representation of objects

In this study, we tested whether in certain experimental conditions the distal and proximal motor components may dissociate in action imitation, and how the distal component and the object representation may interact. Experiments 1-3 were carried out using a dual task procedure in which an action span and a motor suppression were coupled. In Experiment 1, it was shown that action spans were affected more by a distal movement (e.g. distal motor suppression) than by a proximal movement (proximal motor suppression). In Experiment 2, it was demonstrated that the reduction of the action spans was not due to the distal motor suppression being more difficult than the proximal motor suppression. In Experiment 3, pantomimes were replaced with the corresponding objects and the participants were asked to mime the objects, reproducing the appropriate actions. During the presentation of the objects, the participants were engaged in a motor suppression that was performed either by the hand or by the arm. The distal motor suppression reduced the pantomime span more significantly than the proximal motor suppression. Experiment 4 showed that the spans of pantomimes of objects shown in Experiment 3 are longer when participants do not perform motor suppressions. Our results suggest that in normal subjects a difference between the distal and the proximal motor component can be observed under dual task conditions and that distal motor suppression seems to interfere both with the encoding of action and with pragmatic representation of objects.     

糖尿病视网膜病变易感性与相关基因多态性研究进展

糖尿病视网膜病变是糖尿病的并发症之一,在糖尿病患者中,有血糖控制不良且病程较长但未发生糖尿病视网膜病变的情况,也有血糖控制良好且病程较短的但发生严重糖尿病视网膜病变的患者。通过大量的流行病学调查发现,糖尿病视网膜病变的发生、发展除了与血糖控制的情况、病程长短等因素有关外,还与每个人的个体差异有关。     

"She" is not like "I": the tie between language and action is in our imagination

Embodied theories hold that understanding what another person is doing requires the observer to map that action directly onto his or her own motor representation and simulate it internally. The human motor system may, thus, be endowed with a "mirror matching" device through which the same motor representation is activated, when the subject is either the performer or the observer of another's action ("self-other shared representation"). It is suggested that understanding action verbs relies upon the same mechanism; this implies that motor responses to these words are automatic and independent of the subject of the verb. In the current study, participants were requested to read silently and decide on the syntactic subject of action and nonaction verbs, presented in first (1P) or third (3P) person, while TMS was applied to the left hand primary motor cortex (M1). TMS-induced motor-evoked potentials were recorded from hand muscles as a measure of cortico-spinal excitability. Motor-evoked potentials increased for 1P, but not for 3P, action verbs or 1P and 3P nonaction verbs. We provide novel demonstration that the motor simulation is triggered only when the conceptual representation of a word integrates the action with the self as the agent of that action. This questions the core principle of "mirror matching" and opens to alternative interpretations of the relationship between conceptual and sensorimotor processes.