Complete remission with histamine blocker in a patient with intractable hyperadrenergic postural orthostatic tachycardia syndrome secondary to long coronavirus disease syndrome.

The COVID-19 pandemic caused by the novel severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2), has emerged as a global public health concern and its sequels have barely started to outcrop. A good percentage of patients who suffered from COVID-19 are prone to develop long-COVID or post-COVID condition (PCC), a multisystemic, heterogeneous, chronic disorder. Patients with PCC may experience diverse manifestations, of which cardiovascular and neurological symptoms are among the most frequently reported.

Optogenetic and Chemogenic Control of Pain Signaling: Molecular Markers.

Pain is a complex experience that involves physical, emotional, and cognitive aspects. This review focuses specifically on the physiological processes underlying pain perception, with a particular emphasis on the various types of sensory neurons involved in transmitting pain signals to the central nervous system. Recent advances in techniques like optogenetics and chemogenetics have allowed researchers to selectively activate or inactivate specific neuronal circuits, offering a promising avenue for developing more effective pain management strategies.

Predictors of Mechanical Ventilation in Guillain-Barré Syndrome with Axonal Subtypes.

Background: The early clinical predictors of respiratory failure in Latin Americans with Guillain-Barré syndrome (GBS) have scarcely been studied. This is of particular importance since Latin America has a high frequency of axonal GBS variants that may imply a worse prognosis.

Methods: We studied 86 Mexican patients with GBS admitted to the , a referral center of Mexico City, to describe predictors of invasive mechanical ventilation (IMV).

Clinical and neurophysiological description of patients with POEMS syndrome.

Introduction: POEMS syndrome (polyneuropathy, organomegaly, endocrinopathy, monoclonal protein, skin changes) is a monoclonal gammopathy with polyneuropathy as a mandatory criterion.

Objective: To describe potential associations between clinical expression and electrodiagnostic patterns in POEMS syndrome.

Method: Observational, retrospective, cross-sectional study of cases cared for in a referral center, diagnosed with POEMS syndrome from 2009 to 2019.

Sex Differences in the Physiological Network of Healthy Young Subjects.

Within human physiology, systemic interactions couple physiological variables to maintain homeostasis. These interactions change according to health status and are modified by factors such as age and sex. For several physiological processes, sex-based distinctions in normal physiology are present and defined in isolation.

Cardiovascular dysautonomia in Achalasia Patients: Blood pressure and heart rate variability alterations.

Achalasia is a disease characterized by the inability to relax the esophageal sphincter due to a degeneration of the parasympathetic ganglion cells located in the wall of the thoracic esophagus. Achalasia has been associated with extraesophageal dysmotility, suggesting alterations of the autonomic nervous system (ANS) that extend beyond the esophagus. The purpose of the present contribution is to investigate whether achalasia may be interpreted as the esophageal manifestation of a more generalized disturbance of the ANS which includes alterations of heart rate and/or blood pressure.

A physicist's view of homeostasis: how time series of continuous monitoring reflect the function of physiological variables in regulatory mechanisms.

Objective: Homeostasis is one of the key concepts of physiology and the basis to understand chronic-degenerative disease and human ageing, but is difficult to quantify in clinical practice. The variability of time series resulting from continuous and non-invasive physiological monitoring is conjectured to reflect the underlying homeostatic regulatory processes, but it is not clear why the variability of some variables such as heart rate gives a favourable health prognosis whereas the variability of other variables such as blood pressure implies an increased risk factor. The purpose of the present contribution is to quantify homeostasis using time-series analysis and to offer an explanation for the phenomenology of physiological time series.

The charming physician (El médico encantador): neurological conditions in a short story by Silvina Ocampo.

The Argentinian author Silvina Ocampo (1903-1993) left us a vast body of works which are considered outstanding in many ways. In 1960, she published a short story, entitled "El médico encantador" (The Charming Physician), in the renowned literary magazine Sur. The central character of this piece is a family doctor named Albino Morgan, who had a secret truth: in any house he visited, all variety of disease also entered.

From supine to standing: in vivo segregation of myogenic and baroreceptor vasoconstriction in humans.

Myogenic vascular response is a form of systemic and regional vasoconstriction produced increasing the intra-arterial pressure by gravity. Here, the vasoconstriction due to the myogenic response, induced by the gravitational action in a dependent limb, is separated from that caused by the baroreceptor reflex. Regional changes of skin blood flow (SBF), total blood volume of the finger (TBVF), pulse pressure (PP), heart rate (HR), systolic, and diastolic blood pressure (BP) were analyzed in 10 healthy young subjects in supine and upright positions.

[On roman philonium].

The roman philonium (Philonium Romanum) is an example of pharmacological poetry. This opiate was conceived by Philo of Tarsus, who was active during the first century of the Common Era. His antidote was written in elegiac couplets.

Loss of Breathing Modulation of Heart Rate Variability in Patients with Recent and Long Standing Diabetes Mellitus Type II.

Healthy subjects under rhythmic breathing have heart interbeat intervals with a respiratory band in the frequency domain that can be an index of vagal activity. Diabetes Mellitus Type II (DM) affects the autonomic nervous system of patients, thus it can be expected changes on the vagal activity. Here, the influence of DM on the breathing modulation of the heart rate is evaluated by analyzing in the frequency domain heart interbeat interval (IBI) records obtained from 30 recently diagnosed, 15 long standing DM patients, and 30 control subjects during standardized clinical tests of controlled breathing at 0.

Heart Rate and Systolic Blood Pressure Variability in the Time Domain in Patients with Recent and Long-Standing Diabetes Mellitus.

Diabetes Mellitus (DM) affects the cardiovascular response of patients. To study this effect, interbeat intervals (IBI) and beat-to-beat systolic blood pressure (SBP) variability of patients during supine, standing and controlled breathing tests were analyzed in the time domain. Simultaneous noninvasive measurements of IBI and SBP for 30 recently diagnosed and 15 long-standing DM patients were compared with the results for 30 rigorously screened healthy subjects (control).

Heart rate and systolic blood pressure variability on recently diagnosed diabetics.

Background: Diabetes affects approximately 250 million people in the world. Cardiovascular autonomic neuropathy is a common complication of diabetes that leads to severe postural hypotension, exercise intolerance, and increased incidence of silent myocardial infarction.

Objective: To determine the variability of heart rate (HR) and systolic blood pressure (SBP) in recently diagnosed diabetic patients.

Cardiovascular variability in Mexican patients with Parkinson's disease.

Unlabelled: Cardiovascular variability (CVV) has been evaluated in patients with Parkinson's disease (PD) in other countries and exhibit ethnic differences.

Objective: We investigated heart rate variability (HRV) and blood pressure variability (BPV) in Mexican patients with PD.

Method: We further compared HRV and BPV between this group and young healthy controls (YHC) in order to estimate, for the first time in our country, the magnitude of the difference.

An early literary description of emotional syncope in the Fifth Canto of Dante Alighieri's Commedia: 'E caddi come corpo morto cade'.

Dante's Divine Comedy is universally acclaimed as one of the great masterpieces in world literature. It is written in first person singular and this gives an intimate acquaintance with the vision of the poet. In the Fifth Canto, he exquisitely describes the story of Paolo Malatesta and Francesca da Rimini, illicit lovers killed by Francesca's husband, Gianciotto Malatesta.

Initial circulatory response to active standing in Parkinson's disease without typical orthostatic hypotension.

Unlabelled: While the circulatory response to orthostatic stress has been already evaluated in Parkinson's disease patients without typical orthostatic hypotension (PD-TOH), there is an initial response to the upright position which is uniquely associated with active standing (AS). We sought to assess this response and to compare it to that seen in young healthy controls (YHC).

Method: In 10 PD-TOH patients (8 males, 60 ± 7 years, Hoehn and Yahr ≤ 3) the changes in systolic blood pressure (SBP) and heart rate that occur in the first 30 seconds (sec) of standing were examined.

Korotkoff sounds -- the improbable also occurs.

Very few discoveries have had such a large impact on and relevance to clinical medicine as the noninvasive measurement of the diastolic blood pressure. A number of gifted physiologists and clinicians were ineffectively in search of a noninvasive method to determine the diastolic pressure. Nonetheless, the quantification of the diastolic BP was not achieved by any of these clinical or physiological researchers, but by an unlikely and unexpected figure: Nikolai Sergeevich Korotkoff (1874-1920), a young Russian army surgeon, working under precarious conditions in the hardship of diverse wars.

Acido, ergo sum: Holger Hydén--the neuroscientist in Cortázar's Hopscotch.

The fictional Italian author Morelli is throughout the novel "Hopscotch" (1963) Julio Cortázar's alter ego. This character proposes an unoriginal literary hypothesis in chapter 62. There is an allusion to a particular Swedish that 'is working on a chemical theory of thought.

Giovanni Battista Morgagni in the murals of Diego Rivera at the National Institute of Cardiology of Mexico City.

The Italian physician Giovanni Battista Morgagni was the founder of the clinico-anatomical method. His masterpiece De sedibus, et causis morborum per anatomen indagatis represented a major breakthrough in the history of medicine. In the murals of Diego Rivera at the National Institute of Cardiology, Morgagni appears at the center of the fresco.

[A brief history of the baroreceptor reflex: from Claude Bernard to Arthur C. Guyton. Illustrated with some classical experiments].

The baroreceptor reflex is poorly known by most physicians even though is fundamental in stabilizing the blood pressure on a beat to beat basis and is crucial for survival. Its fascinating history is briefly reviewed in this article. In 1852 Claude Bernard discovered that the sympathetic nerves of the neck innervate the blood vessels of the skin of the rabbit.

[Neural control of the peripheral circulation and blood pressure].

In the XIX century Claude Bernard discovered the action of the nervous system on the peripheral circulation. In the first half of the XX century Ewald Hering discovered the baro-receptor and the reflex control of the heart rate and blood pressure. Cowley and Guyton demonstrated that sino-aortic denervation induces persistent changes in the blood pressure in the dog.