Reduced Heart Rate Research Articles

Effectiveness of relaxation techniques for stress management and quality of life improvement in cardiovascular disease and hypertensive patients: a systematic review

ABSTRACT Background and objectives Cardiovascular diseases (CVD) and hypertension are leading causes of morbidity and mortality worldwide, significantly affecting quality of life (QoL). Stress, anxiety, and poor psychological well-being often exacerbate these conditions, creating a vicious cycle. Relaxation techniques, including progressive muscle relaxation (PMR) and diaphragmatic breathing, assist in contracting and relaxing muscle groups to aid individuals in identifying and reducing physical tension and foster relaxation due to increased parasympathetic nerve activity, resulting in emotional tranquility. This systematic review explores the efficacy of relaxation techniques in reducing stress and improving QoL in patients with CVD and hypertension. Materials and methods The review adhered to PRISMA guidelines, searching five major databases (PubMed, EBSCOhost, Web of Science, PsychINFO, and Scopus) with a search time range from 2014 to 2024. This review has been registered on Open OSF (n) 6HYG9. Results The results from several studies highlight the positive effects of relaxation techniques on both cardiovascular health and psychological well-being. Various methods, such as PMR, breathing exercises, and biofeedback, significantly reduced blood pressure (BP), anxiety, and stress levels in hypertensive and cardiovascular patients. Additionally, interventions like Benson’s relaxation and jaw relaxation demonstrated improvements in patient QoL and cardiovascular health outcomes, underscoring the potential benefits of integrating relaxation techniques into treatment programs for heart-related conditions. Conclusions By targeting both the physiological and psychological aspects of the patient’s well-being, these methods contribute to improved BP regulation, reduced heart rate, and alleviation of anxiety and stress symptoms. When incorporated into cardiac rehabilitation programs, these techniques have shown positive effects on emotional well-being and overall QoL, making them a valuable tool for patients recovering from cardiovascular events or managing chronic CVD. More robust, high-quality studies are needed to refine the optimal methods, duration, and frequency of these interventions.

Fluconazole induces cardiovascular toxicity in zebrafish by promoting oxidative stress, apoptosis, and disruption of key developmental genes.

This study systematically evaluated the toxic effects of fluconazole on the cardiovascular development of zebrafish. Zebrafish embryos were treated with different concentrations of fluconazole (200, 400, and 800μg/ml) to observe its impact on heart development, reactive oxygen species (ROS) generation, apoptosis, and hemoglobin production. The results showed that as the concentration of fluconazole increased, significant changes in zebrafish heart structure were observed, along with a notable reduction in heart rate. Pericardial edema and cardiac morphological abnormalities were particularly prominent in the high-dose group. In addition, fluconazole treatment significantly increased ROS levels and induced apoptosis in cardiac cells. Enzyme-linked immunosorbent assay (ELISA) results showed that fluconazole treatment significantly increased the malondialdehyde (MDA) content and reduced superoxide dismutase (SOD) and catalase (CAT) activity, suggesting that oxidative stress and cell death may play a key role in its cardiotoxicity. Quantitative reverse transcription polymerase chain reaction (qRT-PCR) analysis revealed that fluconazole treatment significantly affected the expression of several key genes related to heart development and function, particularly cardiac myosin light chain 2 (cmlc2), ventricular myosin heavy chain (vmhc), and myosin heavy chain 6 (myh6), whose expression changes were closely associated with alterations in heart morphology and function. Transcriptomic analysis showed that several signaling pathways related to cardiac development, apoptosis, and metabolism were affected. In summary, this study reveals the multifaceted cardiotoxic mechanisms of fluconazole in zebrafish and provides new insights into drug safety assessment.

Blood Sampling in Göttingen Minipigs—A Case Study of Two Standard Methods and Clicker Training as a Restraint-Free Alternative

Blood sampling often requires restraint that negatively affects animal welfare. This case study evaluated three methods for jugular vein blood sampling (V-bench, sling, and clicker training) with the overall aim of assessing the negative impact on animal welfare and providing a general recommendation on the use of methods. First, the effects of simulated blood sampling in V-bench and sling on behaviour, heart rate, and saliva cortisol concentrations 15 min after sampling were assessed. The sling (which had the least negative effects) was re-evaluated after one week of habituation to assess a possible positive effect. Clicker training was evaluated using behavioural observations only. The heart rate was significantly higher in animals placed in the V-bench compared to the sling (p < 0.05), but no significant differences were found in the saliva cortisol concentrations. Habituation to the sling resulted in a further reduction in heart rate compared to the V-bench (p < 0.01). When trained to voluntarily cooperate, three out of six minipigs allowed blood sampling from the jugular vein without restraint. We are convinced that all six minipigs would have succeeded if the training environment had been optimised. In conclusion, clicker training results in blood sampling with no negative behaviours displayed such as struggling or squealing/screaming. When restraint is unavoidable, the sling is preferable compared to the V-bench.

Modulation of cardiac autonomic activity across consciousness states and levels of sleep depth in individuals with sleep complaints and bipolar disorder or unipolar depressive disorders

ObjectiveAutonomic nervous system dysfunction and reduced heart rate variability (HRV) often co-exist with mood disorders, a phenomenon likely influenced by sleep disturbances. This study investigated heart rate (HR) and HRV across wake, rapid eye movement (REM) sleep, and non-REM (NREM) sleep in individuals with sleep complaints and bipolar or unipolar depressive disorder. MethodsPolysomnographic data was retrospectively collated for 120 adult patients with sleep complaints and depressive symptoms [60 diagnosed with bipolar disorder, 60 diagnosed with a unipolar depressive disorder], and 60 healthy controls. HR and time-based HRV variables were computed on 30-s segments and averaged across the night for wake, NREM and REM sleep. ResultsSignificant group by consciousness state interactions showed that the unipolar and bipolar groups had lower standard deviation of normal-to-normal intervals root mean square of successive R-R interval differences compared to controls during NREM and REM sleep, but not during wake (SDNN: F(4, 330) = 3.0, p = .021, np2 = 0.035; RMSSD: F(4, 332) = 5.8, p < .001, np2 = 0.065). The magnitude of these group differences did not vary significantly between NREM 1, NREM 2 and NREM 3 sleep. These interactions persisted after excluding individuals taking 3rd generation antipsychotic, lithium, anticonvulsant, and cardiovascular medications. ConclusionAlthough further work is required to account for the impact of psychotropic and cardiac medications, as well as manic and euthymic states, these findings suggest that the sleep-based autonomic signature of depressive states differs across different types of mood disorders and could potentially inform the development of biomarkers and therapeutic targets.

Effects of early ivabradine therapy in patients with acute heart failure: A meta-analysis and systematic review

BACKGROUND: Although ivabradine is the agent of choice for reducing heart rate, its use in acute heart failure patients remains unclear. OBJECTIVES: To evaluate the potential of in-hospital ivabradine administration in reducing heart rate, the risk of rehospitalization, mortality, and clinical profile in acute heart failure patients using a meta-analysis approach. METHODS: The study was designed as a meta-analysis conducted from August to September 2024. We selected several database sources for the search strategy, including PubMed, Google Scholar, ProQuest, British Medical Journal, and American Journal of Cardiology. Data on the outcomes of ivabradine treatment compared to standard therapy were collected to determine cumulative point estimates. For statistical analysis, we used the Mantel–Haenszel test for categorical data or inverse variance for continuous data. RESULTS: We included 11 articles in the study. Our findings indicated that, in comparison to the standard therapy group, the ivabradine group was associated with improvements in resting heart rate, a reduction in the risk of rehospitalization, a decrease in cardiovascular mortality, a reduction in all-cause mortality, a shorter length of stay, improvements in New York Heart Association (NYHA) classification, better Left Ventricular Ejection Fraction (LVEF), and improved B-type Natriuretic Peptide (BNP) / N-terminal pro b-type Natriuretic Peptide (NT-proBNP) levels. CONCLUSION: In conclusion, this study has revealed the beneficial effects of using ivabradine for the treatment of acute heart failure. Keywords: acute heart failure, beta blocker, heart rate, ivabradine, meta-analysis.

Determining the Efficacy of Providing Ice Compression for Fitness Enhancement After Speed Endurance Exercise on Reducing Heart Rate, IL-6, and Fatigue Index in Football Athletes

Determining the Efficacy of Providing Ice Compression for Fitness Enhancement After Speed Endurance Exercise on Reducing Heart Rate, IL-6, and Fatigue Index in Football Athletes

Cardiac muscle contracts more efficiently at lower contraction frequencies.

This study investigated how contraction frequency impacts the mechano-energetics of cardiac muscle performing mechanical work. Left-ventricular trabeculae were isolated from rat hearts and mounted in our work-loop calorimeter to assess their function at physiological temperature (37°C) across three stimulation frequencies, 2 Hz, 3.5 Hz and 5Hz, in a randomised sequence. Each trabecula was subjected to two experimental protocols: work-loop contractions under a range of afterloads and isometric contractions under a range of muscle lengths. Two contraction protocols allowed the partition of the various components of energy expenditure during cardiac contraction. By simultaneously measuring force-length work and heat output, mechanical efficiency was calculated over a range of afterloads to determine the peak value. Our findings revealed that force production, activation heat (energy associated with Ca2+ cycling) and cross-bridge heat were unaffected by stimulation frequency. Trabeculae produced greater work output per twitch at 2 Hz and 3.5Hz than at 5Hz. Positive correlations among work output, shortening extent and mechanical efficiency were detected. From these findings it was concluded that the higher work output at lower frequencies is associated with greater extent of shortening, which correlates to greater mechanical efficiency. This study highlights the mechano-energetic advantage of ventricular trabeculae in terms of increased work output and energy efficiency gained from operating at lower contraction frequencies, supporting the notion that heart rate reduction produces direct benefits on cardiac energetics.

Розвиток гіпотензії та брадикардії під впливом пропофолу у щурів з цукровим діабетом

Propofol is an anesthetic that is widely used in clinical practice and recommended for patients with diabetes mellitus because it produces less complications compared to other anesthetics. Furthermore, surgical procedures may result in the develop ment of hypoxia. The aim of our study was to investigate the effect of propofol on systemic vascular contractility, mean arterial pressure (MAP), and heart rate (HR) under normoxia and hypoxia in rats with streptozotocin-induced type 1 diabetes (DM). The effect of propofol (10-9 - 3×10-4 mol/l) on the aortic segments of rats with DM caused a significant dose-dependent relaxation compared with control rats. A single intravenous injection of propofol caused no alterations in the hemodynamics of control rats. Still, it induced a dosedependent reduction in HR and MAP in rats with DM under the maximum dose of the study at normoxia. The administration of propofol under hypoxic hypoxia (HH) caused no decrease in MAP but reduced HR in control rats. In rats with diabetes, propofol treatment under HH induced a gradual decrease in MAP and HR, and the reduction in HR was significantly larger than in control rats. HH, which was exposed to animals after propofol administration, produced a significant decrease in MAP compared to rats without the treatment in both groups of rats. HH caused no changes in HR in control rats regardless of pretreatment with propofol but in rats with DM after propofol administration, hypoxic exposure induced a significant decrease in HR, which was accompanied by a rapid drop in MAP and bradycardia for 37.5% of the animals. Therefore, propofol caused no alterations in hemodynamic parameters in healthy rats under normoxia but reduced HR and MAP in rats with DM. Especially this effect was manifested under hypoxia. The data obtained can help to develop guidelines for propofol use in patients with DM.

Association between exposure to particulate matter and heart rate variability in vulnerable and susceptible individuals

Particulate matter (PM) exposure can reduce heart rate variability (HRV), a cardiovascular health marker. This study examines PM1.0 (aerodynamic diameters <1 μm), PM2.5 (≥1 μm and <2.5 μm), and PM10 (≥2.5 μm and <10 μm) effects on HRV in patients with environmental diseases as chronic disease groups and vulnerable populations as control groups. PM levels were measured indoors and outdoors for five days in 97 participants, with 24-h HRV monitoring via wearable devices. PM exposure was assessed by categorizing daily cumulative PM concentrations into higher and lower exposure days, while daily average PM concentrations were used for analysis. Results showed significant negative associations between exposure to single and mixtures of different PM metrics and HRV across all groups, particularly in chronic airway disease and higher air pollution exposed groups. These findings highlight that even lower PM levels may reduce HRV, suggesting a need for stricter standards to protect sensitive individuals.

Differential effects of sound interventions tuned to 432 Hz or 443 Hz on cardiovascular parameters in cancer patients: a randomized cross-over trial

BackgroundThis study investigated whether a sound intervention tuned to 432 Hz (Hz) yields differential effects on cardiovascular parameters and psychological outcomes compared to 443 Hz, which is the concert pitch in German professional orchestras.MethodsUsing a randomized cross-over design, patients with cancer were recruited to receive both a 15-minute sound intervention with a body monochord tuned to 432–443 Hz. Before (pre) and after (post) intervention, cardiovascular parameters were measured using the VascAssist2.0. In addition, visual analogue scales (VAS) for emotional well-being, anxiety, stress, pain and sadness were also assessed pre and post intervention.Results43 patients (8 male, 35 female) with a median age of 61 years (range 35–86) were included. Both interventions led to a significant reduction in heart rate with a more pronounced effect for 432 Hz (median reduction − 3 bpm (432 Hz) vs. median reduction − 1 bpm (443 Hz), p = 0.04). While heart rate variability was increased exclusively by 432 Hz (median increase + 3 ms, p = 0.01), both vascular resistance (median reduction − 5%, p = 0.008) and stiffness (median reduction %, p = 0.04) were significantly reduced by 432 Hz, which was not observed at 443 Hz. Nevertheless, these effects were not significantly different compared to 443 Hz. On the other hand, 432 Hz led to a reduced pulse wave velocity (median reduction − 0.5 m/s, p < 0.001), which was also significantly different compared to 443 Hz (p < 0.001). Improvement in VAS was observed for both groups, with significant increases in emotional well-being and reduction in fatigue, anxiety and stress for both intervention timepoints, although the majority showed no increased VAS scores even before the intervention (median values 0 for anxiety and stress).ConclusionSound interventions tuned to 432–443 Hz exert both positive effects in cancer patients. While psychological outcomes are improved by both interventions, 432 Hz leads to a more pronounced but not significantly different effect to 443 Hz on objective cardiovascular parameters, which reflect deeper relaxation.

Precise modelling of mitochondrial diseases using optimized mitoBEs.

The development of animal models is crucial for studying and treating mitochondrial diseases. Here we optimized adenine and cytosine deaminases to reduce off-target effects on the transcriptome and the mitochondrial genome, improving the accuracy and efficiency of our newly developed mitochondrial base editors (mitoBEs)1. Using these upgraded mitoBEs (version 2 (v2)), we targeted 70 mouse mitochondrial DNA mutations analogous to human pathogenic variants2, establishing a foundation for mitochondrial disease mouse models. Circular RNA-encoded mitoBEs v2 achieved up to 82% editing efficiency in mice without detectable off-target effects in the nuclear genome. The edited mitochondrial DNA persisted across various tissues and was maternally inherited, resulting in F1 generation mice with mutation loads as high as 100% and some mice exhibiting editing only at the target site. By optimizing the transcription activator-like effector (TALE)binding site, we developed a single-base-editing mouse model for the mt-Nd5 A12784G mutation. Phenotypic evaluations led to the creation of mouse models for the mt-Atp6 T8591C and mt-Nd5 A12784G mutations, exhibiting phenotypes corresponding to the reduced heart rate seen in Leigh syndrome and the vision loss characteristic of Leber's hereditary optic neuropathy, respectively. Moreover, the mt-Atp6 T8591C mutation proved to be more deleterious than mt-Nd5 A12784G, affecting embryonic development and rapidly diminishing through successive generations. These upgraded mitoBEs offer a highly efficient and precise strategy for constructing mitochondrial disease models, laying a foundation for further research in this field.

The Holistic Effect of Complementary Interventions in Reducing Stress in College Students.

The purpose of this research was to examine the holistic effects of combined complementary therapies in reducing stress in college students. This convergent mixed-method study provided aromatherapy, massage, and meditation music sessions to college students (N = 50) just before finals week. Paired t-tests analyzed pre-session and post-session perceived stress and anxiety as well as objective physiological measures, including salivary cortisol, heart rate, and blood pressure. There was a significant difference in the scores for perceived stress before and after the sessions, t(49) = 4.72, p < .001, as well as pre-anxiety and post-anxiety, t(49) = 10.27, p < .001. Additionally, salivary cortisol levels significantly reduced from pre-session to post-session t(49) = 2.76, p = .008; and a significant reduction in heart rate from pre-session to post-session, t(49) = 3.73, p < .001. This study demonstrates that 20 min of brief complementary interventions can alter students' subjective holistic health perspectives, with objective physiological data confirming changes that promote health and wellbeing.

Short-Term Warm-Water Immersion for Improving Whole-Body Heat Loss in Older Men.

Exercise-induced heat acclimation can mitigate age-related reductions in heat-loss capacity, though performing repeated bouts of strenuous exercise in the heat may be untenable for many older adults. While short-term passive heat acclimation (e.g., ≤7 days of warm-water immersion) enhances whole-body heat loss in young adults, evidence of its efficacy in older adults is lacking. Thus, we examined whether 7-days warm-water immersion would improve whole-body heat loss in older adults. Twelve habitually active older men (median [IQR] age: 68 [64-73] years; peak oxygen uptake (V̇O2peak): 34.1 [29.4-36.1] mLO2·kg-1·min-1) completed 7 consecutive days of ~90-minutes warm-water immersion (~40 °C) with core (rectal) temperature clamped at ~38.5 °C for the final 60 minutes. Before and after the warm-water immersion intervention, whole-body total (evaporative + dry) heat loss was measured via direct calorimetry during three, 30-minute bouts of cycling at increasing fixed rates of metabolic heat production (150, 200, 250 W·m-2), each separated by 15-minutes rest, in a hot-dry environment (40 °C, ~13% relative humidity). Rectal temperature and heart rate were measured continuously. Following 7 days of warm-water immersion, whole-body total heat loss was elevated by 23 [95% confidence interval: 14, 31] W·m-2 across exercise bouts (acclimation-effect: P < 0.001; interaction: P = 0.598). This was paralleled by reductions in core temperature and heart rate of 0.3 [0.2, 0.4] °C and 11 [8, 14] beats·min-1 (both, acclimation-effect: P < 0.001; interaction: P = 0.288), respectively. Seven consecutive days of warm-water immersion improved whole-body heat loss and reduced core temperature and cardiovascular strain across light-to-vigorous intensity exercise in habitually active older men. Passive heat acclimation may be an efficacious alternative to exercise-heat acclimation to improve heat-loss capacity. Studies are warranted to assess effectiveness in more heat-vulnerable populations.

Sex-based variations in breath-holding: oxygen storage and diving response among non-divers.

Breath-hold diving performances are typically better in men than in women. However, it is still being determined if there are differences in the physiological responses to breath-holding between the sexes. We conducted a study comparing the maximum breath-hold duration, heart rate (HR) reduction, peripheral oxygen saturation (SpO2), and spleen volume and contraction in 37 men and 44 women, all of whom had no prior breath-holding experience. They performed two dry apneas separated by 2min; the first was limited to 60s, followed by a maximal effort apnea. HR and SpO2 were measured continuously. Spleen diameters were measured via ultrasonography before and immediately following each apnea. The maximal apneic duration was longer in men (78 ± 19s) compared with women (61 ± 18s, p < 0.001), while the HR reduction was similar (women: 16% ± 19% versus men: 16% ± 17%, p = 0.973). The absolute splenic contraction was greater in men (59 ± 56mL) compared with women (35 ± 28mL, p < 0.001) in the first apnea, while the relative contraction was similar (women: 21% ± 17% versus men: 23% ± 13%, p = 0.528). In addition, the lowest SpO2 during the maximal apnea was similar between sexes (women: 93.3% ± 4.4%; men: 91.9% ± 4.3%, p = 0.161). We conclude that men have larger spleen size and contraction, lung size, and maximal apneic duration than women. The cardiovascular diving response is similar between sexes for those inexperienced with apneic diving. The longer breath-hold duration in men may be partly due to greater oxygen storage capacity, which results from larger vital capacity and greater spleen size and contraction.

Comparison of the efficacy and safety of Landiolol and Esmolol in critically ill patients: a propensity score-matched study

BackgroundExcessive tachycardia is associated with impaired hemodynamics and worse outcome in critically ill patients. Previous studies suggested beneficial effect of β-blockers administration in ICU patients, including those with septic shock. However, comparisons in ICU settings are lacking. Our study aims to compare Landiolol and Esmolol regarding heart rate control and hemodynamic variables in general ICU patients.MethodsThis retrospective, observational study was conducted in a 56-bed ICU at a university hospital. A propensity score matching (PSM) was employed to balance baseline differences. Generalized estimating equations (GEE) were used to compare heart rate between two drugs. The primary outcome was heart rate control, while secondary outcomes included hemodynamic response, hospital length of stay (HLOS) and ICU length of stay (ICULOS).ResultsFrom June 2016 to December 2022, 438 patients were included after PSM, (292 in the Esmolol group and 146 the in Landiolol group). Baseline heart rate was similar between groups (Landiolol:120.0 [110.2, 131.0] bpm vs. Esmolol:120.0 [111.0, 129.0] bpm, p = 0.925). During 72 h. of β-blocker infusion, Landiolol reduced heart rate by 4.7 (1.3, 8.1) bpm, more than Esmolol (p = 0.007), while preserving a comparable proportion of patients able to stabilize vasopressor doses within the first 24 h. (82.9 vs. 80.8%, respectively, p = 0.596). Norepinephrine doses and lactate levels were similar between groups over 72 h., while the Landiolol group exhibited notably higher minimal ScvO2 levels (72% [63%, 78%] vs 68% [55%, 73%], respectively, p = 0.006) and a lower maximal PCO2 gap compared to the Esmolol group (7.0 [6.0, 9.0] vs. 8.0 [6.0, 10.0] mmHg, respectively, p = 0.040). Patients in the Landiolol group were observed to experience shorter HLOS than patients in the Esmolol group (26.5 [13.0, 42.0] vs 30.0 [17.0, 47.2] days, respectively, p = 0.044) and ICULOS (4.9 [2.8, 10.0] vs.6.7 [3.4, 13.1] days, respectively, p = 0.011).ConclusionLandiolol provides superior heart rate control in critically ill patients with tachycardia compared to Esmolol, without increasing vasopressor requirements during the first 24 h. Findings from ScvO2 levels and PCO2 gap suggest that Landiolol may exert less impact on cardiac output than Esmolol. Further studies, incorporating comprehensive hemodynamic monitoring, are warranted to clarify the clinical implications of heart rate control with β-blockers in ICU patients with tachycardia.

The Effectiveness and Safety of Beta Antagonists in Patients With Burns: An Updated Meta-Analysis.

The purpose of this systematic review was to assess the safety and effectiveness of beta antagonists for improving clinical care in burn patients, compared to placebo. Articles from randomized-controlled trials were identified by a literature search on PubMed and Cochrane. We included relevant trials involving patients with burn. Trials were eligible if they evaluated propranolol and compared to usual care or placebo. We conducted a meta-analysis using a random-effects model. A total of 2114 patients were included from 14 RCTs. Beta-blocker-treated patients had decreased heart rates (WMD = -14.73, 95% CIs = [-19.14, -10.32]), mean arterial pressure (WMD = -2.76, 95% CIs = [-3.81, -1.70]), rate pressure product (WMD = -1.13, 95% CIs = [-1.56, -0.71]), reduced time for wound healing (WMD = -5.08, 95% CIs [-8.97, -1.18]), and lower resting energy expenditure (WMD = -168.83, 95% CIs [-232.03, -105.63]). However, use of beta-blockers did not reduce mortality rate (WMD = 0.98, 95% CIs [0.68, 1.41]), incidence of sepsis (RR = 0.82, 95% CIs = [0.50, 1.35]), or length of stay in hospital (WMD = -1.50, 95% CIs [-4.76, 1.77]) compared with placebo. Our findings indicate that the administration of propranolol to burned patients does not contribute to increased mortality rates, reduced length of hospital stays, or heightened sepsis occurrence. It demonstrates a protective effect on heart function by reducing heart rate, resting energy expenditure, rate pressure product, and wound healing. More randomized-controlled and multi-center studies are needed to effectively establish the use of beta antagonists in burn patients.

Fish early-life stage toxicity and environmental relevance: What does high-dose toxicity testing tell us?

Abstract The early-life stage (ELS) toxicity syndrome for fish is well described and has been reported in hundreds of toxicity studies. It is generally characterized by a reduced heart rate, yolk sac and pericardial edemas, and various morphological abnormalities, the most common being spinal curvature. For many of those studies it appears that the ELS toxicity syndrome is the result of non-specific (baseline) toxicity that occurs at aqueous and whole-body concentrations that are just below lethal concentrations. Baseline toxicity is essentially a non-specific response that results from chemicals accumulating in and disturbing the function of biological membranes that leads to lethality and sublethal effects at relatively high doses. The commonality of this acute ELS toxicity syndrome among highly diverse organic and inorganic chemicals is remarkable. It is important to identify baseline toxicity because it is considered minimal toxicity that acts in all tissues and cells, and it has the potential to impair all cellular functions. This means if an effect is observed around baseline-toxic concentrations, it is likely that other cellular functions are also affected, ie, the effect is not specific. The fish ELS toxicity syndrome can also be the result of specific effects involving receptor interactions; therefore, we emphasize the importance of distinguishing between specific and non-specific toxicity responses to provide the most relevant data for environmental risk assessment.

Nalbuphine Verses Midazolam On Hemodynamic Response To Laryngoscopy And Tracheal Intubation In Patients Undergoing Laparoscopic Cholecystectomy.

Objective: This study sought to compare the haemodynamic responses to laryngoscopy and tracheal intubation between Nalbuphine and Midazolam to assess their efficacy and safety in clinical practice. Study Design: A Randomized Control Trial (RCT) Place and Duration of the Study: Department of Anesthesia at Faculty of Allied Health Sciences, Superior University, Lahore and duration of the study was six months from jan 2024 to june 2024 Materials and Methods: A randomized controlled experiment Trial was performed at Department of Anesthesia Faculty of Allied Health Sciences involving 168 people, evenly split into two groups: Group N (Nalbuphine, n=84) and Group M (Midazolam, n=84). The inclusion criteria were patients aged 20 to 60 years, classified as ASA I or II, who were scheduled for laparoscopic cholecystectomy. Participants received either Nalbuphine or Midazolam preoperatively, and hemodynamic parameters (heart rate, systolic and diastolic blood pressure, mean arterial pressure, and SPO₂) were assessed at baseline and at 2, 4, 6, 8, and 10 minutes following intubation. Statistical analyses encompassed t-tests for group comparisons and regression analysis to ascertain drivers of mean arterial pressure. Results: The trial comprised 168 subjects, equally allocated to Group N (Nalbuphine) and Group M (Midazolam), with no statistically significant differences in demographic factors including age (p = 0.482), gender (p = 0.742), weight (p = 0.632), or surgical time (p = 0.601). Initially, hemodynamic parameters were comparable; however, post-induction, substantial differences emerged, with Group N demonstrating reduced heart rate (p = 0.001), systolic blood pressure (p = 0.000), diastolic blood pressure (p = 0.000), and mean arterial pressure (p = 0.000) at all time points. Regression analysis revealed significant predictors of mean arterial pressure (MAP), including heart rate (β = 0.45, p = 0.000), systolic blood pressure (BP) (β = 0.32, p = 0.001), and diastolic BP (β = 0.56, p = 0.000). Conversely, group membership exhibited a significant negative correlation (β = -5.25, p = 0.000), indicating a preference for Nalbuphine in achieving enhanced hemodynamic stability. Conclusion: The study determined that Nalbuphine offered superior hemodynamic stability relative to Midazolam during laryngoscopy and tracheal intubation in laparoscopic cholecystectomy. Nalbuphine was correlated with markedly reduced heart rate, blood pressure, and mean arterial pressure at all measured intervals. Keywords: Nalbuphine, Midazolam, laryngoscopy, tracheal intubation, laparoscopic cholecystectomy

Sex Influence on Trigeminal Nerve Stimulation and Breath-Hold Diving Performance: Examination of the Autonomic Regulation of Cardiovascular Responses to Facial Cooling and Apnoea Across Sex and Varied Factors.

This review emphasises the importance of the cardiovascular response to facial cooling (FC) and breath holding in both sexes. The trigemino-cardiac reflex, triggered by FC, reduces heart rate (HR) and constricts blood vessels. When combined with breath holding, this effect intensifies, enhancing the cardiodepressive impact. The cardiovascular reaction to this combination, known as the cold-water face immersion or simulated diving test, varies among individuals and depends on their cardiovascular regulatory profiles, which differ between men and women. Despite extensive research on the cardiovascular response to FC and apnoea, most studies did not categorise participants by sex, leading to a limited understanding of how it influences trigeminal nerve stimulation (TGS) and breath-hold diving (BHD). Despite attempts to address this, the existing findings remain inconsistent due to intra- and inter-individual variability. Key factors influencing the diving response include the influence of the parasympathetic system on HR, vascular sympathetic activity affecting total peripheral resistance (TPR), sensitivity to CO2, lung capacity, training, physical performance, duration of apnoea, and the stimulation of metaboreceptors in working muscles. These factors differ between men and women, potentially contributing to variations in the effectiveness of the response to the FC combined with breath holding.

Toxicity of rare earth elements europium and samarium on zebrafish development and locomotor performance.

Rare earth elements are integral to modern technology, but their increasing environmental distribution due to anthropogenic activities poses potential health risks to humans. This study utilized zebrafish as a model to assess developmental and locomotor performance effects of europium and samarium. Exposure to Eu or Sm induced a reduction in heart rate, growth inhibition, and morphological deformities. RNA-Seq revealed gene expression alterations linked to critical biological processes and functions following Eu or Sm exposure. Impaired organogenesis in liver and exocrine pancreas, evident through fluorescence imaging, was confirmed transcriptionally. Exposure to Eu or Sm significantly impaired the burst and spontaneous swimming behaviors of zebrafish larvae, characterized by pronounced reductions in movement distance, frequency, and velocity. These observations indicate severe locomotor dysfunction in zebrafish exposed to Eu and Sm. The comprehensive downregulation of the oxidative phosphorylation pathway is likely a primary factor contributing to these motor impairments. Apoptosis induced by Eu and Sm, confirmed through acridine orange staining, was accompanied by the upregulation of the intrinsic apoptosis pathway. Our findings contribute critical insights into the health risks of rare earth elements, informing risk assessment and management strategies.