A chronic dysfunctional stress response can cause stroke by stimulating platelet activation, migraine, and hypertension

Microextraction combined with microderivatization for drug monitoring and protein modification analysis from limited blood volume using mass spectrometry

In the clinic, ethosuximide is commonly used to treat generalized absence seizures but has recently been repurposed for other diseases. Because of adverse effects and drug interactions, high-throughput therapeutic drug monitoring of ethosuximide is necessary. Microextraction is a simple, effective, rapid, and low consumption of organic solvents method for sample preparation. In this study, microderivatization-increased detection (MDID)-combined microextraction was used to detect ethosuximide by mass spectrometry. Ethosuximide is a difficult to retain and ionize compound in the C18 nano-flow column and ionization interface, respectively. Hence, we developed a fast method for detecting ethosuximide in human plasma by using the MDID strategy (within 2 min). Chemical microderivatization parameters were studied and optimized to increase the sensitivity of ethosuximide detection at trace levels. The linear range for the analysis of ethosuximide in 10 μL plasma was 5-500 μg/mL with a coefficient of determination (r²) ≥ 0.995. The precision and accuracy of intraday and interday analyses of ethosuximide were below 13.0%. Furthermore, modifications of major proteins in plasma and blood cells, induced by ethosuximide, were identified. The proposed method effectively utilizes microliter samples to detect drug plasma concentrations under suitable microextraction procedures toward the eco-friendly goal of low consumption of organic solvents. Graphical abstract ᅟ.

CLINICAL-EPIDEMIOLOGICAL STUDY ON STROKE PRESENCE IN THE POPULATION OF HERZEGOVINA-NERETVA CANTON INFLUENCED BY INVESTIGATED RISK FACTORS

INTRODUCTION

Stroke is a rapid loss of brain function due to disturbance blood flow to the brain. The existence of multiple risk factors, the length of their duration, and severity of each factor individually, is positively correlated with the occurrence of stroke. Stroke is the third cause of disability and premature death for men and women.

AIM

The aim of this research is that through clinical and epidemiological studies the origin and development of stroke to inspect the same level of representation in the population of the Herzegovina-Neretva Canton.

MATERIAL AND METHODS

This survey covers the entire population of residents in the Herzegovina-Neretva Canton, and the number of patients who had a need for primary and secondary treating the symptoms of stroke. The very setting of this model of anthropological research modern human groups and theoretical estimates of the impact of genetic and / or environmental risk factors in the formation of phenotypic expression of complex traits of stroke, at the population level, resulted in the realization of the very methodology of this research. The study was conducted at the Department of Neurology, Regional Medical Center (RMC) "Dr. Safet Mujic" and the Department of Neurology, Clinical Center Mostar. These two health institutions, in addition to primary care are at the disposal for entire population of the Herzegovina-Neretva Canton and beyond. Data were collected by examining the details of the history of the board of hospitalized patients in the period from 1 January 2010-to 31 December 2014. The processed are 10 risk factors-potential causes of stroke. We also as research material, used records of hospital morbidity-the disease-illness statistics form (form number: 03-21-61; 03/02/60; 03/02/61; 09/03/60).

RESULTS

In our study, stroke is the second most frequent in the period of investigation, and noted the rapid growth that is in 2010 and 10.21% to 14.52% in 2014. There was a slight statistically significant differences in relation to the number of infected men and women, and the same is in favor of the patients are female. The number of patients with ischemic stroke, 954 of them or 48.38% was male and 1,018 or 51.62% were female. Of the 10 possible risk factors, factor 6 has a statistically significant canonical factor value, of which hypertension-CVI and the level of P = 0009 *, p = secondary hypertension, 0034 *, hypertensive heart disease, p =, * 0021, Diabetes mellitus of P = 0029 *, p = Anemia, 0052 * and C-reactive protein (CRP) of p = 0049 *, respectively, these canonical factors carry the entire amount of information about the relations impact of certain risk factors in the onset and development of the brain shock.

CONCLUSION

We conclude that there is a statistically significant correlation between the studied risk factors in the genesis of the origin and development of different types of stroke.

Infralimbic Endothelin1 Is Critical for the Modulation of Anxiety-Like Behaviors

Endothelin1 (ET1) is a potent vasoconstrictor that is also known to be a neuropeptide that is involved in neural circuits. We examined the role of ET1 that has been implicated in the anxiogenic process. We found that infusing ET1 into the IL cortex increased anxiety-like behaviors. The ET(A) receptor (ET(A)R) antagonist (BQ123) but not the ET(B) receptor (ET(B)R) antagonist (BQ788) alleviated ET1-induced anxiety. ET1 had no effect on GABAergic neurotransmission or NMDA receptor (NMDAR)-mediated neurotransmission, but increased AMPA receptor (AMPAR)-mediated excitatory synaptic transmission. The changes in AMPAR-mediated excitatory postsynaptic currents were due to presynaptic mechanisms. Finally, we found that the AMPAR antagonists (CNQX) and BQ123 reversed ET1's anxiogenic effect, with parallel and corresponding electrophysiological changes. Moreover, infusing CNQX + BQ123 into the IL had no additional anxiolytic effect compared to CNQX treatment alone. Altogether, our findings establish a previously unknown anxiogenic action of ET1 in the IL cortex. AMPAR-mediated glutamatergic neurotransmission may underlie the mechanism of ET1-ET(A)R signaling pathway in the regulation of anxiety.

[Stress as a risk factor in the development of brain stroke]

INTRODUCTION

In many developing countries and in countries in transition, an increased incidence of cerebrovascular disease has been observed. The aim of this study was to determine the influence of acute and chronic stress on the development of acute brain stroke and its relapse.

MATERIAL AND METHODS

The study included all recorded cases of cerebrovascular disease in the municipality of Doljevac in the period 2005-2007 (the stroke victims), and 230 healthy controls. By using the method of interview, the frequency of chronic stress situations was examined, as well as the occurrence of acute stress situations 24 hours prior to the acute brain stroke and its relapse.

RESULTS

In the group which consisted of stroke victims, a large number of subjects was found to have had an acute stress 24 hours prior to the onset of the disease, and the type of stress which proved to be statistically significant was the one which had been provoked by problems between family members (Chi2 = 4,03: p = 0,04). All of the chronic stressors were more frequent in the group consisting of stroke victims than in the control group and among the statistically significant stressors were stressful situations in the family and at work. In recidivists, a greater presence of acute and chronic stressors was observed, but the statistical significance was not proved when this disease occurred again.

CONCLUSION

The presence of acute stressors was found to have been more frequent in the group of stroke victims 24 hours prior to the onset of the disease. The effect of acute and chronic stressors upon the brain stroke recidivism has not been statistically proved yet.

Redrawing Papez’ circuit: A theory about how acute stress becomes chronic and causes disease

The diseases of chronic stress include migraine, essential hypertension, depression, and the metabolic syndrome. A theory is presented to explain how acute stress becomes chronic and causes these inter-related conditions. The theory is based on a new "circuit of emotion", which is derived from Papez' famous theory of emotion. The hypothesis is as follows: There is a basic circuit of emotion which runs from the hippocampus (defined as the dentate gyrus plus the CA regions), where emotion arises, to the amygdala and from there to serotonergic pacemaker cells in the dorsal raphe nucleus (DRN). The DRN projects back to the dentate gyrus in two ways: a direct route without a stop and an indirect route via pacemaker cells in the entorhinal cortex. The purpose of the direct route is to promote neurogenesis in the subgranular zone of the dentate; the indirect route has two purposes: to imprint ongoing moments of consciousness onto new dentate cells for retention as memory and to provide a negative feedback loop for regulation of the whole process. The hippocampus, the amygdala, and the DRN all project to the hypothalamus, which are branches off the basic loop that subserve the autonomic expression of emotion. Pathologic overdrive of the DRN causes overdrive of the entorhinal cortex, which leads to excitotoxic cell death of neurons in the hippocampus involved in the negative feedback loop. The disinhibited amygdala and DRN are then free to orchestrate the syndromes of chronic stress. Recovery from chronic stress requires repopulation of the dentate gyrus and restoration of the feedback loop. Excitotoxic cell death in the hippocampus results from either extraordinary acute stress or increased susceptibility to DRN overdrive, as might be caused, for example, by genetic factors, age, high cortisol levels, or incomplete recovery from previous damage. Three goals for therapeutic intervention are identified: inhibition of pacemaker cells in the DRN (which can be targeted by ethosuximide and other drugs that block serotonergic pacemaker currents), inhibition of pacemaker cells in the entorhinal cortex (which can be targeted by anti-epileptic drugs that block pacemaker currents in the entorhinal cortex, e.g. phenytoin), and restoration of serotonin levels in the dentate gyrus (which can be accomplished with anti-depressants). It is logical to use drugs from all three categories, either alone on in combination, to treat any of the four diseases of chronic stress. This leads to novel therapeutic recommendations, e.g. the use of ethosuximide, mood-stabilizers, and anti-depressants in synergy to treat essential hypertension.

A new theory of cryptogenic stroke and its relationship to patent foramen ovale; or, the puzzle of the missing extra risk

Cryptogenic stroke (or stroke of undetermined cause) is a common cause of stroke and is statistically associated with patent foramen ovale (PFO). The largest study of cryptogenic stroke is the Homma study, which is a sub-study of the WARSS trial; it produced the following data: cryptogenic stroke patients with and without PFO, when treated with either aspirin or warfarin, all had identical recurrence rates. This is puzzling because it seems as though there ought to have been some extra risk in one of the two groups under one of the two treatments. How could everything come out the same? A review of the epidemiology of cryptogenic stroke shows that, compared to patients with stroke of determined cause, cryptogenic stroke patients are a little younger and have lower doses of the usual risk factors (hypertension and diabetes mellitus) but more PFO. Cryptogenic strokes appear to be embolic strokes from an unknown source. A previously published article setting forth a hypothetical theory of stress-induced stroke was used to analyze these data. It is suggested that stress can induce episodic systemic platelet activation and hypercoagulability, which causes transient thrombus formation and subsequent embolization on both the arterial and venous sides of the circulation; the latter requires a PFO to cause a stroke (paradoxical embolism). The sum of these two mechanisms explains cryptogenic stroke. The PFO subset of cryptogenic stroke includes patients with both early and late stage disease who have an aggregate risk approximately equal to that of patients without PFO. Cryptogenic stroke is part of the disease of stress-induced cerebrovascular disease. Aspirin and warfarin have already been shown to be equally effective in secondary prevention of ischemic stroke.

Factor XII (Hageman factor) is a missing link between stress and hypercoagulability and plays an important role in the pathophysiology of ischemic stroke

A new hypothesis is presented on the function of factor XII, which is postulated to be a "missing link" between acute stress and transient hypercoagulability. The implications of this idea are developed to show how chronic stress, which involves activation of hypertension and migraine as well as hypercoagulability, can cause of cerebrovascular disease. "Acute stress" is defined as "the normal short-term physiological response to the perception of major threats or demands". "Chronic stress" is "the abnormal ongoing physiological response to the continuing perception of unresolvable major threats or demands". The factor XII hypothesis is as follows: Acute stress includes release of epinephrine by the adrenal medulla. Epinephrine activates platelets by binding to alpha-2A adrenergic receptors. Activated platelets convert pre-bound factor XII to its active form, which then initiates the intrinsic coagulation cascade. This can be called the "activated platelet initiation pathway" for coagulation. Neither tissue factor nor pre-formed thrombin is required. Thrombosis proceeds to completion, but only a minute amount of thrombin is formed, and the process normally stops at this point. In people who lapse into a state of chronic stress, essential hypertension, which is also a manifestation of stress, synergizes with hypercoagulability: there is both a baseline rise in blood pressure and systemic platelet activation as well as superimposed labile rises of both. Upregulation of these two stress parameters is atherogenic: epinephrine-activated platelets stimulating thrombin formation interact with endothelial cells activated by angiotensin II to cause, first, smooth muscle cell proliferation, which is a histological hallmark of atherosclerosis, and, lastly, a symptomatic thrombotic occlusion-the stroke. The migraine symptoms which often accompany this process are a marker of chronic stress and ongoing pathophysiologic damage. Therapeutic predictions are made regarding novel ways of blocking stress-induced hypercoagulability and hypertension. Hypercoagulability could be targeted by monoclonal antibodies directed against the platelet-specific alpha-2 adrenergic receptor or the (putative) platelet receptor for Factor XII; hypertension could be treated with monoclonal antibodies directed against the beta-adrenergic receptor in the juxtaglomerular apparatus or by surgical denervation of the kidneys, either of which would decrease the renin release which helps drive the hypertension.