Journal of Basic and Clinical Physiology and Pharmacology最新文献

Ventricular fibrillation (VF) is a major cause of sudden cardiac death in humans. Currently used antiarrhythmic drugs are aimed at preventing initiation of VF by decreasing the incidence of arrhythmias which can lead to VF. This approach today seems to be insufficient. On the basis of reports that VF can terminate spontaneously in various mammals, and even in humans, we propose pharmaceutical enhancement of self-ventricular defibrillation as a new therapeutical approach. Data obtained over the last decade indicate that a high cardiac extraneuronal norepinephrine level during VF facilitates selfdefibrillation. Dibenzazepines (tricyclic antidepressants) and phenothiazines elevate norepinephrine level by inhibiting norepinephrine reuptake and were found to exhibit defibrillatory activity. The relationship of chemical structure to defibrillatory activity was studied in a group of dibenzazepine and phenothiazine compounds.

Four types of ion-selective channels were found by the patch-clamp technique in the human erythroleucemia K562 cells. I)In cell-attached configuration at potentials less negative than -40 mV an 8 pS channel was detected. The potential dependence of channel activity suggests that this is the TTX-sensitive Na+ channel. II)A cation-selective channel was observed with equal permeability for Na+ and K+ and a potential-independent single-channel conductance of 19 pS. The channel is activated by intracellular Ca2+ and inhibited by TEA. ΙΠ)A predominantly anion-selective channel was identified with the selectivity sequence N03" >J" > G" = Br » S04 2·. The single-channel conductance shows outward rectification, and is in symmetrical NaCl solution 19 pS at -60 mV and 54 pS at +50 mV. The open- and closedtime distributions suggest one open and at least four closed states. At submicromolar concentrations, the open state is blocked by H2DIDS leading to channel flicker between open and blocked channel; higher concentrations (apparent Kj=6.8 μΜ) lead to a longer-lasting blocked state. Both components of inhibition are reversible. IV)In addition, an 8 pS, Na+- and K+- selective channel could be induced by application of palytoxin. For channel activity, the presence of extracellular Na+ is essential. It is assumed that the Na+, K+-pump molecule is involved in the channel formation. Similarly, it is discussed whether the anionselective channel represents a pore conformation of an electrically silent anion exchanger.

Body fluid distribution was measured in three donkeys, fully hydrated, following dehydration and after being rapidly rehydrated. In twenty other donkeys that were slaughtered to supply food for predators iri a safari zoo, the water content in the different compartments of the gastrointestinal tract (GIT) was assessed. Prior to being slaughtered, four of the animals were fully hydrated, four dehydrated and 12 dehydrated, rehydrated and then slaughtered and examined, four at 1, four at 3 and four at 5 hours following drinking. When the body mass of dehydrated donkeys dropped to 75.4± 2.4% of their initial value, total body water of the animals (HTO space), extracellular volume (SCN space) and plasma volume (EB space) were reduced to 76.6 ± 5.3%, 80.9 ± 10.6% and 73.2 ± 8.3% of their initial values, respectively. The amount of water retained in the GIT of the fully hydrated donkeys amounted to 15.9 ± 3.4 1, 19% of total body water. In the dehydrated donkeys it was only 7.4± 1.3 1. The calculated total intracellular volume in the dehydrated donkeys was only 14% lower than in the fully hydrated animals. When drinking was allowed, dehydrated donkeys consumed 17.6 ± 2.4 1 of water. The increase in the water content in the gut of newly rehydrated donkeys matched this volume, 80% of which was retained in the hind gut. During the five hours after drinking, only slow and moderate changes in the volume of the hind gut were recorded. Changes in plasma volume were also suppressed. It is suggested that the hind gut of the donkey, similar to the rumen of goats and sheep, plays a role as a water reservoir that helps maintain the osmotic stability of the body.

Clinical success in prevention of sudden cardiac death has been poor. New approaches to prevention of ventricular fibrillation (VF), one of the main causes of sudden cardiac death, are clearly needed. In the present article we have reviewed some of our own data which support the notion that VF may be prevented by manipulation of chloride homeostasis /1,2/. Our studies have revealed a novel approach to VF suppression via alteration of sarcolemmal membrane resistance.

Point-of-care testing (POCT) refers to decentralized testing done using complex but compact, portable devices that can be done near the site at the patient's bedside. These enable quick diagnosis and timely intervention because turnaround time (TAT) decreases with these devices. They can also be operated by non-medical personnel and patients with minimum expertise as these devices are easy to handle and interpret. This increases patient awareness regarding their diseases and benefits doctors in giving more patient-centered care. POCT devices require minimum setup and can be utilized even in remote places. The present review focuses on POCT devices employed specifically in clinical biochemistry, e.g., glucose, HbA1c, cardiac biomarkers, fertility tests, hematological analysis, electrolytes, enzymes, urine dipstick tests, etc. This introductory review delves into comprehending the fundamentals of POCT technologies, their guidelines, applications, advantages, and disadvantages. It covers a broad overview of the tests done and the samples required to process these tests. It also compares the pros and cons of POCT devices over centralized laboratory testing. The review also aims to emphasize the relevance of its use in today's era, current trends regarding POCT in urban and rural setups, challenges faced in the field during its implementation, and the potential areas of improvement in the future. However, it is advisable to seek references for more detailed and critical information regarding all the specific topics given in this review article.

Objectives: The study focuses exclusively on the results of an arterial blood gas report, which reveal a phenomenal contradiction if one follows the physiological and physicochemical approaches as well as the standard base excess determination to interpret an acid-base disturbance. The aim of this article is not to fully describe a clinical case and make a differential diagnosis but to analyze the blood gas report data in detail and present the conclusions that result from the application of the different approaches that exist for the interpretation of acid-base disorders.

Methods: The results of an arterial blood gas report of a patient with severe lactic acidosis were cross-examined using the standard base excess method and the physiologic and physiochemical approaches. The causes of the contradiction are discussed with a commentary on the underlying pathophysiology.

Results: The study revealed the presence of a normal anion gap (even after correction for albumin levels), a slightly increased strong ion gap and a moderately decreased standard base excess in a patient with severe lactic acidosis.

Conclusions: This real-life case provides an opportunity to give a brief overview of the current methods for investigating acid-base disturbances in a practical way, emphasizing both the common background and the conceptual differences and similarities.

Incretin-based medicines have considerably impacted the treatment of type 2 diabetes mellitus (T2DM), providing considerable advantages in glycemic regulation, weight control, and cardiovascular results. This narrative review examines progress in incretin medicines, encompassing glucagon-like peptide-1 (GLP-1) receptor agonists, dual-receptor, and triple-receptor agonists, while emphasizing their therapeutic advantages, obstacles, and prospective developments. The examined articles were sourced from databases including PubMed and Google Scholar, concentrating on publications predominantly from 2010 to 2024. Selective foundational papers released before this timeline were incorporated to furnish critical historical context about incretin processes and their discovery. Incretin-based medicines, despite their therapeutic efficacy, encounter hurdles including elevated treatment costs, patient compliance difficulties, and variability in response attributable to genetic and physiological variables. Moreover, there are still deficiencies in comprehending the long-term cardiovascular safety and cancer risks linked to these medicines. Emerging dual- and triple-receptor agonists demonstrate potential in overcoming the shortcomings of conventional GLP-1 receptor agonists, providing enhanced metabolic results and broader uses in intricate disease profiles. Future research must concentrate on economic obstacles, streamlined regimens, customized medicine, the integration of artificial intelligence, patient stratification, as well as the safety and efficacy of incretin-based medicines for holistic management of T2DM.

Objectives: Male infertility affects 20-30 % of infertile couples worldwide, and varicocele being a common cause. The relationship between leptin, a hormone involved in energy homeostasis and reproduction, and male fertility parameters remains incompletely understood, particularly in the context of varicocele and obesity. Thus, the current study sought to assess the associations between seminal plasma leptin and other clinical and demographic data of infertile patients.

Methods: In this cross-sectional study, 90 men (29 with varicocele, 61 without) were evaluated from November 2023 to March 2024. Seminal plasma leptin levels were measured using ELISA. Study subjects were classified into three weight classifications using body mass index (BMI) measurements: normal weight, overweight, and obese. Semen analysis, reproductive hormones assessment, and correlation analyses were performed to examine relationships between leptin levels and various clinical parameters.

Results: Patients with varicocele demonstrated significantly higher seminal plasma leptin levels compared to those without (9.27 vs. 7.65 ng/mL, p<0.05), this association persisted following statistical adjustment for demographic and clinical variables. In addition, BMI was the strongest independent predictor of seminal plasma leptin levels (β=0.26, p<0.01). Interestingly, overweight individuals showed higher leptin levels than both normal weight and obese participants. A significant inverse relationship found between leptin concentrations and luteinizing hormone levels (ρ=-0.375, p<0.05), while a positive association was found with progressive motility of sperm (ρ=0.225, p<0.05).

Conclusions: Higher levels of leptin were found in seminal specimens of varicocele-diagnosed subjects and strongly correlate with BMI in this Middle Eastern population. These results together propose that leptin's level in semen could be useful as a biological indicator for varicocele-associated male fertility issues.