The Effects of Menstrual Cycle Phase on Cardiovascular and Pulmonary Responses to Behavioral and Exercise Stress

The present study was designed to compare the differential cardiopulmonary and hemodynamic responses of Type A and B women to an exercise and a psychological stressor. In addition, the effects of menstrual cycle phase on the resting and response levels of a wide range of physiological variables were explored. Thirty-two women participated in a progressive exercise stress test and a threat of shock video game during both the luteal and follicular phases of the menstrual cycle. Half of these subjects expressed the coronary-prone behavior pattern referred to as Type A, as assessed by the Jenkins Activity Survey. The remaining women were relatively free of these behaviors (Type B). Heart rate, oxygen consumption, carbon dioxide production, minute ventilation, and end-tidal carbon dioxide were monitored and recorded on a breath-by-breath basis. Systolic and diastolic blood pressure measures were taken at 2-min intervals. Results indicated similar baseline, exercise, and behavioral stress responses among Type A and B women. The stress responses were also the same between the follicular and luteal phases for all measured physiological variables. However, resting levels of heart rate, metabolism, and ventilation were all elevated at rest during the luteal phase. A regression analysis based on the exercise heart rate and oxygen consumption data demonstrated that a majority of subjects exhibited heart rate responses in excess of that expected during the psychological stressor. These data are discussed with special reference to possible mechanisms of the pathophysiology of cardiovascular disease.     

Dopamine, serotonin and noradrenaline changes in the striatum of C57BL mice following myelin oligodendrocyte glycoprotein (MOG) 35-55 and complete Freund adjuvant (CFA) administration.

Many data suggest involvement of inflammation in neurodegeneration. However, the exact mechanisms of this cooperation are poorly understood. We have previously shown that induction of inflammatory reaction, both before and after injury of the striatum, affects regeneration of dopaminergic neurons. In the present research we studied the role of inflammatory reaction in non-injured striatum. We used myelin oligodendrocyte glycoprotein (MOG) 35-55 in complete Freund's adjuvant (CFA) to elicit experimental autoimmune encephalomyelitis (EAE) mice model. As determined by HPLC, striatal dopamine (DA) and serotonin levels in mice treated with either MOG 35-55 in CFA or CFA alone were significantly higher compared to vehicle-treated controls on 13th day after induction. The ratio of homovanilic acid/dopamine (HVA/DA) and 3, 4 dihydroxyphenylacetic acid/dopamine (DOPAC/DA) were significantly lower in the MOG and CFA groups on 13th day, indicating decreased DA metabolism. Noradrenaline (NA) concentration did not differ between groups. Moreover, the striatal mRNA IL-1beta and TNF-alpha levels were elevated during induction phase of EAE in both groups, as determined by RT-PCR. Our data indicate regulatory connection between dopaminergic and immune systems.     

The relationship between exposure duration,carboxyhemoglobin, blood glucose,pyruvate and lactate and the severity of intoxication in 39 cases of acute carbon monoxide poisoning in man

The relationship between exposure duration, COHb, blood glucose, pyruvate and lactate and the severity of intoxication was investigated in a group of 39 cases of acute CO poisoning treated in the Clinical Toxicology Center in ód, Poland.On the basis of clinical criteria the patients were classified into cases of mild, moderate, severe and very severe CO poisoning. COHb and carbohydrate metabolites were estimated in venous blood taken immediately after admission of the patient to hospital prior to treatment.The severity of intoxication did not correlate with blood COHb; variation in exposure duration seems to be responsible for this phenomenon. Severe and very severe poisonings were associated with longer exposures and were accompanied by a markedly higher blood lactate level, compared to mild and moderate cases. Blood pyruvate depended less than lactate on the severity of intoxication. Blood glucose depended neither on exposure duration nor on the severity of intoxication.Among the carbohydrate metabolic parameters studied, blood lactate determination can be helpful in the evaluation of the severity of CO poisoning in man.     

Potentiation by deprenyl of the autoreceptor-mediated inhibition of [3H]-5-hydroxytryptamine release by 5-methoxytryptamine

Summary The 5-hydroxytryptamine (5HT) receptor agonist, 5-methoxytryptamine, inhibited in a concentration-dependent manner the electrically-evoked release of ³H-5HT from superfused rat hypothalamic slices, with an IC₅₀ of 560 nmol/l, without affecting the spontaneous outflow of radioactivity. In the presence of the selective monoamine oxidase B (MAO B) inhibitor, (–)-deprenyl (1 mol/l), the concentration-effect curve for 5-methoxytryptamine was shifted significantly to the left, and the IC₅₀ was decreased to 25 nmol/l. Under the same experimental conditions, the potency of the 5HT receptor agonist lysergic acid diethylamide (LSD) at inhibiting the electrically-evoked release of ³H-5HT was the same in the presence as well as in the absence of (–)-deprenyl. The IC₅₀ values for LSD were 34 nmol/l in the absence of deprenyl, and 31 nmol/l in the presence of the MAO B inhibitor. It is concluded that deprenyl potentiates the inhibition by 5-methoxytryptamine of ³H-5HT release, by preventing its inactivation through MAO B. Since 5-methoxytryptamine may be present in the pineal gland of some species, the potent effects of this 5-HT receptor agonist on seretoninergic neutrotransmission may be of physiological relevance.     

Differential effects of α-β-methylene ATP on responses to nerve stimulation in SHR and WKY tail arteries

Summary The effects of ,-methylene-adenosine triphosphate, (,-methylene ATP, a P₂-receptor desensitising agent) have been evaluated on vasoconstrictor responses elicited by exogenous agonists or electrical field stimulation in isolated perfused SHR or WKY tail arteries and on tritium release elicited by electrical field stimulation in SHR-tail arteries pre-labeled with ³H-noradrenaline.Exposure to ,-methylene ATP (0.1 mol/l) significantly inhibited vasoconstrictor responses to electrical field stimulation in SHR tail arteries. These inhibitory effects were not further increased at a higher concentration of ,-methylene ATP (1 mol/l). In WKY tail arteries, ,-methylene ATP (1 mol/l) failed to significantly inhibit vasoconstrictor responses to electrical stimulation.In SHR tail arteries prelabelled with ³H-noradrenaline, ,-methyleneATP (1 mol/l) did not inhibit the stimulation evoked release of tritium. However, at this concentration, ,-methylene ATP significantly antagonized the vasoconstrictor responses of SHR tail arteries induced by exogenous ATP (1 mol/l), ,-methylene ATP (30 mol/l), a stable agonist at P₂-receptors, or 60 mmol/l KCl. These effects of ,-methylene ATP on contractile responses to KCl were not observed in WKY-tail arteries.In tail arteries obtained from reserpine pretreated SHR, despite a 85–95% decrease in endogenous noradrenaline tissue content, the vasoconstrictor responses induced by periarterial field stimulation were greatly diminished, but not abolished. These residual responses to periarterial field stimulation were not antagonized by prazosin (0.1 mol/l), but were practically abolished by the addition of ,-methylene ATP (1 mol/l).In tail arteries from WKY rats pretreated with reserpine, exposure to prazosin (0.1 mol/l) further reduced the residual responses elicited by electrical field stimulation. In these WKY-tail arteries, addition of ,-methylene ATP (1 mol/l) did not further inhibit the remaining vasoconstrictor response obtained in the presence of prazosin.While our results suggest a significantly greater cotransmitter role for ATP with noradrenaline in tail arteries of SHR compared with control normotensive WKY rats, additional effects of ,-methylene ATP not involving P₂ receptors cannot be entirely excluded.     

Brainstem afferents to the omnipause region in the cat: a horseradish peroxidase study

"Omnipause" neurons (OPNs), located in the nucleus raphe pontis and the reticular formation, actively suppress saccadic eye movements during intersaccadic intervals. To determine the brainstem afferents that may inhibit the OPNs and thereby allow a saccade to occur, we injected horseradish peroxidase into the raphe pontis of four cats at the site of physiologically identified OPNs. Labeled neurons were found in a number of brainstem nuclei. The greatest concentrations, composed of small to medium-sized neurons, were located in a group of nuclei around the habenulopeduncular tract, in the rostral mesencephalic reticular formation, in the deep layers of the superior colliculus, and in parts of the subjacent cuneiform and subcuneiform reticular nuclei. Smaller numbers were found in the nucleus reticularis pontis oralis. Caudal to the injection site, labeled neurons were scattered in parts of the nuclei reticularis gigantocellularis, paragigantocellularis dorsalis, and paragigantocellularis lateralis. A few neurons were labeled in a restricted region of the causal part of the nucleus prepositus hypoglossi and in the nucleus reticularis medullaris ventralis. Larger numbers of neurons were labeled in the dorsal column nuclei and in parts of the cochlear nuclei. Smaller numbers were found in the spinal trigeminal nucleus, the lateral nucleus of the superior olive, and the fastigial nucleus of the cerebellum. The nonreticular brainstem projections may contribute sensory information in a number of modalities since OPNs respond to visual, somesthetic, and auditory stimuli. Our findings indicate a number of regions that may contain neural elements impinging on the OPNs. The best prospects for a saccade initiation signal from one of the labeled populations appear to be the meso-diencephalic reticular formation and/or the superior colliculus.     

Does Drinking Coffee and Tea Affect Bone Metabolism in Patients with Inflammatory Bowel Diseases?

Patients suffering from Crohn’s disease and ulcerative colitis are at higher risk of osteoporosis due to lower bone mineral density. Risk factors of osteoporosis are divided into unmodifiable, namely, age, gender, genetic factors, as well as modifiable, including diet, level of physical activity, and the use of stimulants. Coffee and tea contain numerous compounds affecting bone metabolism. Certain substances such as antioxidants may protect bones; other substances may increase bone resorption. Nevertheless, the influence of coffee and tea on the development and course of inflammatory bowel diseases is contradictory.     

A Vicious Cycle of Osteosarcopenia in Inflammatory Bowel Diseases—Aetiology,Clinical Implications and Therapeutic Perspectives

Sarcopenia is a disorder characterized by a loss of muscle mass which leads to the reduction of muscle strength and a decrease in the quality and quantity of muscle. It was previously thought that sarcopenia was specific to ageing. However, sarcopenia may affect patients suffering from chronic diseases throughout their entire lives. A decreased mass of muscle and bone is common among patients with inflammatory bowel disease (IBD). Since sarcopenia and osteoporosis are closely linked, they should be diagnosed as mutual consequences of IBD. Additionally, multidirectional treatment of sarcopenia and osteoporosis including nutrition, physical activity, and pharmacotherapy should include both disorders, referred to as osteosarcopenia.     

Milk and Dairy Products: Good or Bad for Human Bone? Practical Dietary Recommendations for the Prevention and Management of Osteoporosis

Osteoporosis affects women twice as often as men. Additionally, it is estimated that 0.3 million and 1.7 million people have hip fractures in the USA and Europe, respectively. Having a proper peak bone mass and keeping it as long as possible is especially important for osteoporosis prevention. One of the most important calcium sources is milk and dairy products. Breast milk is the best infant food, but milk should not be avoided later in life to prevent losing bone mass. On the other hand, more and more people limit their milk consumption and consume other dairy or non-dairy products. For example, they are usually replaced with plant beverages, which should be consumed carefully in several age groups. Additionally, an important element of milk and dairy products, as well as plant beverages, are probiotics and prebiotics, which may modulate bone turnover. Dietary recommendations focused on milk, and dairy products are an important element for the prevention of osteoporosis.     

Management of lung transplantation in the COVID-19 era—An international survey

It is unknown if solid organ transplant recipients are at higher risk for severe COVID-19. The management of a lung transplantation (LTx) program and the therapeutic strategies to adapt the immunosuppressive regimen and antiviral measures is a major issue in the COVID-19 era, but little is known about worldwide practice. We sent out to 180 LTx centers worldwide in June 2020 a survey with 63 questions, both regarding the management of a LTx program in the COVID-19 era and the therapeutic strategies to treat COVID-19 LTx recipients. We received a total of 78 responses from 15 countries. Among participants, 81% declared a reduction of the activity and 47% restricted LTx for urgent cases only. Sixteen centers observed deaths on waiting listed patients and eight centers performed LTx for COVID-19 disease. In 62% of the centers, COVID-19 was diagnosed in LTx recipients, most of them not severe cases. The most common immunosuppressive management included a decreased dose or pausing of the cell cycle inhibitors. Remdesivir, hydroxychloroquine, and azithromycin were the most proposed antiviral strategies. Most of the centers have been affected by the COVID-19 pandemic and proposed an active therapeutic strategy to treat LTx recipients with COVID-19.