Medical hypotheses
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Obstructive sleep apnea syndrome (OSAS) is defined by recurrent episodes of significant reduction or absence of the oro-nasal airflow during sleep, in the presence of thorax and abdominal movements and snoring. The pathophysiological consequences of intermittent hypoxia determined by OSAS are represented by systemic inflammation, the release of free oxygen radicals and activation of the sympathetic nervous system. Cardiac arrhythmias are a frequent comorbidity in patients with OSAS. ⋯ Fibrinogen and ESR cannot be used for monitoring the CPAP therapy in patients with OSAS and arrhythmias. Instead, the beneficial effect of CPAP in patients with OSAS and cardiac arrhythmias can be monitored with the help of the RDW, which could also be used for evaluating the cardiovascular risk in patients with OSAS and arrhythmias.
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Our creativity is challenged daily when facing new situations asking for novel solutions. Creativity, a multicomponent construct includes flexible divergent and rigid convergent thinking. ⋯ The question how psychedelics induce this state of enhanced flexible thinking remains to be answered and investigating the neurobiology underlying this phenomenon will not only help in understanding why psychedelics are of use in the therapeutic setting but also in other settings where flexible thinking is challenged. A model including neuronal networks, neurotransmitters and personal factors playing a role in this process will be proposed which can be put to the test by means of placebo-controlled pharmaco-imaging studies in healthy volunteers.
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Pain-related fear can exacerbate physical disability and pathological pain in complex regional pain syndrome (CRPS) patients. We conducted a kinematic analysis of grasping movements with a pediatric patient suffering from CRPS in an upper limb to investigate how pain-related fear affects motor control. Using a three-dimensional measurement system, we recorded the patient's movement while grasping three vertical bars of different diameters (thin, middle, thick) with the affected and intact hands. ⋯ Although MGD and PV increased with target size, the TOP was longer in the affected hand when grasping the thick bar. These findings indicate that pain-related fear impairs motor commands that are sent to the musculoskeletal system, subsequently disrupting executed movements and their sensory feedback. Using kinematic analysis, we objectively demonstrated that pain-related fear affects the process of sending motor commands towards the musculoskeletal system in the CRPS-affected hand, providing a possible explanatory model of pathological pain.
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Fibromyalgia (FM) is a debilitating, widespread pain disorder that is assumed to originate from inappropriate pain processing in the central nervous system. Psychological and behavioral factors are both believed to underlie the pathogenesis and complicate the treatment. This hypothesis, however, has not yet been sufficiently supported by scientific evidence and accumulating evidence supports a peripheral neurological origin of the symptoms. ⋯ Associated symptoms, such as bladder and bowel dysfunction, result from compression of the sacral nerve root fibers, and facial pain and paresthesia result from compression of the cranial nerve root fibers. Idiopathic Intracranial Hypertension, Normal Pressure Hydrocephalus and the clinical entity of symptomatic Tarlov cysts share similar central and peripheral neurological symptoms and are likely other manifestations of the same condition. The hypothesis presented in this article links the characteristics of fibromyalgia and unexplained widespread pain to cerebrospinal pressure dysregulation with support from scientific evidence and provides a conclusive explanation for the multitude of symptoms associated with fibromyalgia.
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Among 700,000 new and recurrent ischemic stroke patients per year, forty percent are hyperglycemic on admission. In-vitro, hyperglycemia is toxic to neurons. Acute ischemic stroke patients who are hyperglycemic on admission experience higher morbidity and mortality. ⋯ The lack of improved outcomes with normoglycemia in this population dictates reconsideration of assumptions regarding the underlying pathophysiology of hyperglycemia. Review of the current data suggests there are two distinct pathophysiologic entities of hyperglycemia in acute ischemic stroke patients: diabetic and non-diabetic. We propose that the lack of positive results from well-designed intention-to-treat trials in hyperglycemic acute ischemic stroke patients could be attributed to treating these distinct groups as one.