The Cys22-Cys27 disulfide bond of factor X (FX) protease domain is not conserved among coagulation factors and its contribution to the physiological haemostasis and implication in the pathogenesis of haemostatic and thrombotic disorders remain to be elucidated. Mutation p.Cys27Ser was identified in a pedigree of congenital FX deficiency and fluorescence labelling study of transiently transfected HEK293 cells showed accumulation of FX p.Cys27Ser within cell, indicating incompetent secretion partially responsible for the FX deficiency. The clotting activity of FX p.Cys27Ser was decreased to about 90% of wild-type, while amidolytic and pro-thrombinase activities (kcat/Km) determined with recombinant FXa mutant were 1.33- and 4.77-fold lower. Molecular dynamic simulations revealed no major change in global structure between FXa p.Cys27Ser and wild-type FXa; however, without the Cys22-Cys27 disulfide bond, the insertion of newly formed N terminal of catalytic domain after the activation cleavage is hindered, perturbing the conformation transition from zymogen to enzyme. The crystal structure of FXa shows that this disulfide bond is solvent accessible, indicating that its stability might be subject to the oxidation/reduction balance. As demonstrated with FX p.Cys27Ser here, Cys22-Cys27 disulfide bond may modulate FX clotting activity, with reduced FX pertaining less pro-coagulant activity.

The Disulfide Bond between Cys22 and Cys27 in the Protease Domain Modulate Clotting Activity of Coagulation Factor X.

Thrombosis and Haemostasis

The administration of an anticoagulant in patients with liver disease (nonalcoholic steatohepatitis-NASH, nonalcoholic fatty liver disease-NAFLD, chronic hepatitis, or cirrhosis) who have an indication (atrial fibrillation, venous thrombosis, or pulmonary embolism) is challenging because there is an imbalance between thrombosis and bleeding. There is a need to focus our attention on preventing risk factors because diabetes, obesity, dyslipidemia, smoking, and sedentary behavior are risk factors for both NASH/NAFLD and AF, and these patients require anticoagulant treatment. Patients with advanced liver disease (Child-Pugh C) were excluded from studies, so vitamin K antagonists (VKAs) are still recommended. Currently, VKAs are recommended for other conditions (antiphospholipid syndrome, mitral valve stenosis, and mechanical valve prosthesis). Amongst the patients under chronic anticoagulant treatment, especially for the elderly, bleeding as a result of the improper use of warfarin is one of the important causes of emergency admissions due to adverse reactions. DOACs are considered to be efficient and safe, with apixaban offering superior protection against stroke and a good safety profile as far as major bleeding is concerned compared to warfarin. DOACs are safe in the Child-Pugh A and B classes (except rivaroxaban), and in the Child-Pugh C class are contraindicated. Given that there are certain and reliable data for chronic kidney disease regarding the recommendations, in liver function impairment more randomized studies must be carried out, as the current data are still uncertain. In particular, DOACs have a simple administration, minimal medication interactions, a high safety and effectiveness profile, and now a reversal agent is available (for dabigatran and idarucizumab). Patients are also statistically more compliant and do not require INR monitoring.

Oral Anticoagulation in Patients with Chronic Liver Disease.

Medicina

Helicobacter pylori ( H. pylori ) infection, which affects approximately half of the world's population, remains a serious public health problem. As H. pylori infection leads to a number of gastric pathologies, including inflammation, gastroduodenal ulcers, and malignancies, early detection and treatment are crucial to preventing the spread of the infection. Multiple extragastric complications, such as iron deficiency anaemia, immune thrombocytopenic purpura, vitamin B12 deficiency, diabetes mellitus, cardiovascular diseases, and certain neurological disorders, have also been linked to H. pylori infection. An awareness of H. pylori and associated health hazards is necessary to minimize or even eradicate the infection. Therefore, there is an urgent need to raise the standards for the currently employed diagnostic, eradication, alternative treatment strategies. In addition, a brief overview of traditional and cutting-edge approaches that have proven effective in identifying and managing H. pylori is needed. Based on the test and laboratory equipment available and patient clinical characteristics, the optimal diagnostic approach requires weighing several factors. The pathophysiology and pathogenic mechanisms of H. pylori should also be studied, focusing more on the infection-causing virulence factors of this bacterium. Accordingly, this review aims to demonstrate the various diagnostic, pathophysiological, therapeutic, and eradication tactics available for H. pylori , emphasizing both their advantages and disadvantages. Invasive methods (such as quick urease testing, biopsy, or culture) or noninvasive methods (such as breath tests, stool investigations, or serological tests) can be used. We also present the most recent worldwide recommendations along with scientific evidence for treating H. pylori . In addition to the current antibiotic regimens, alternative therapies may also be considered. It is imperative to eradicate the infections caused by H. pylori as soon as possible to prevent problems and the development of stomach cancer. In conclusion, significant advances have been made in identifying and treating H. pylori . To improve eradication rates, peptide mass fingerprinting can be used as a diagnostic tool, and vaccines can also eliminate the infection.

 Helicobacter pylori Infection: Current Status and Future Prospects on Diagnostic, Therapeutic and Control Challenges.

Antibiotics

Heart failure with preserved ejection fraction (HFpEF), defined as HF with an EF of 50% or higher at diagnosis, affects approximately 3 million people in the US and up to 32 million people worldwide. Patients with HFpEF are hospitalized approximately 1.4 times per year and have an annual mortality rate of approximately 15%.

Risk factors for HFpEF include older age, hypertension, diabetes, dyslipidemia, and obesity. Approximately 65% of patients with HFpEF present with dyspnea and physical examination, chest radiographic, echocardiographic, or invasive hemodynamic evidence of HF with overt congestion (volume overload) at rest. Approximately 35% of patients with HFpEF present with "unexplained" dyspnea on exertion, meaning they do not have clear physical, radiographic, or echocardiographic signs of HF. These patients have elevated atrial pressures with exercise as measured with invasive hemodynamic stress testing or estimated with Doppler echocardiography stress testing. In unselected patients presenting with unexplained dyspnea, the H2FPEF score incorporating clinical (age, hypertension, obesity, atrial fibrillation status) and resting Doppler echocardiographic (estimated pulmonary artery systolic pressure or left atrial pressure) variables can assist with diagnosis (H2FPEF score range, 0-9; score &gt;5 indicates more than 95% probability of HFpEF). Specific causes of the clinical syndrome of HF with normal EF other than HFpEF should be identified and treated, such as valvular, infiltrative, or pericardial disease. First-line pharmacologic therapy consists of sodium-glucose cotransporter type 2 inhibitors, such as dapagliflozin or empagliflozin, which reduced HF hospitalization or cardiovascular death by approximately 20% compared with placebo in randomized clinical trials. Compared with usual care, exercise training and diet-induced weight loss produced clinically meaningful increases in functional capacity and quality of life in randomized clinical trials. Diuretics (typically loop diuretics, such as furosemide or torsemide) should be prescribed to patients with overt congestion to improve symptoms. Education in HF self-care (eg, adherence to medications and dietary restrictions, monitoring of symptoms and vital signs) can help avoid HF decompensation.

Approximately 3 million people in the US have HFpEF. First-line therapy consists of sodium-glucose cotransporter type 2 inhibitors, exercise, HF self-care, loop diuretics as needed to maintain euvolemia, and weight loss for patients with obesity and HFpEF.

Heart Failure With Preserved Ejection Fraction: A Review.

JAMA

Background Ventricular ectopy is observed in most of the population ranging from isolated premature ventricular contractions to rapid hemodynamically unstable ventricular tachyarrhythmias like ventricular tachycardia and ventricular fibrillation. Multiple mechanisms exist for ventricular arrhythmias such as triggered activity, reentry, and automaticity. Scar-based reentry forms the basis of most malignant VA that can lead to sudden cardiac death. Many antiarrhythmic drugs have been utilized for the suppression of ventricular arrhythmia. They are commonly classified using the Vaughan-Williams-Singh classification which distinguishes them based on the predominant action on different phases of the cardiac action potential. Class Ic agents are widely used in premature ventricular contraction suppression but are contraindicated in patients with prior myocardial infarction or ischemic scar, and heart failure. Beta-blockers continue to be a mainstay in the treatment of most symptomatic VA and are well tolerated, relatively safe, and have additional benefits in symptomatic coronary heart disease and left ventricular systolic dysfunction. Amiodarone continues to be used for the management of most cases of serious VA especially in the acute setting when accompanied by hemodynamic perturbations but has the disadvantage of having a poor toxicity profile for long-term use Summary Historically used for long-term ventricular arrhythmia suppression and prevention of sudden cardiac death, antiarrhythmics are now used to reduce implantable defibrillator shocks and symptoms. They still have a role in premature ventricular complex suppression in patients with failed catheter ablation or those who are not candidates for invasive therapy. Newer concepts in cardiac imaging and the use of artificial intelligence may help further delineate sudden cardiac risk and identify patients that may benefit from pharmacological management. Key Message Anti-arrhythmic agents continue to perform an important role in the suppression of ventricular arrhythmias especially channelopathies, polymorphic VT, and idiopathic ventricular fibrillation. Judicious use of these agents while recognizing side effects can help reduce the long-term effects of ventricular arrhythmias on cardiac function.

Pharmacotherapy in Ventricular Arrhythmias.

Cardiology

Beyond improving hemoglobin A1c (HbA1c) in adults with type 2 diabetes, glucagon-like peptide 1 receptor agonists (GLP-1RA) have been approved for reducing risk of major adverse cardiovascular events (MACE) with established cardiovascular disease (CVD) or multiple CV risk factors. Sodium-glucose cotransporter 2 inhibitors (SGLT2i) also reduced the risk for the primary composite CV outcome in patients with type 2 diabetes at high risk for CV events. In the American Diabetes Association (ADA) and European Association of Study in Diabetes (EASD) consensus report 2022, there is the description "In people with established atherosclerotic CVD (ASCVD) or with a high risk for ASCVD, GLP-1RA were prioritized over SGLT2i"; however, the evidence supporting such statement is limited. Therefore, we studied the superiority of GLP-1RA over SGLT2i for prevention of ASCVD from various viewpoints. We could not find a meaningful difference in the risk reduction in three-point MACE (3P-MACE), mortality due to any cause, mortality due to CV cause and nonfatal myocardial infarction between GLP-1RA and SGLT2i trials. The risk of nonfatal stroke decreased in all five GLP-1RA trials; however, two of three SGLT2i trials showed an increase in risk of nonfatal stroke. The risk of hospitalization for heart failure (HHF) decreased in all three SGLT2i trials, and one GLP-1RA trial showed an increase in risk of HHF. The risk reduction of HHF in SGLT2i trials was greater than that in GLP-1RA trials. These findings were consistent with current systematic reviews and meta-analyses. The risk reduction of 3P-MACE was significantly and negatively correlated with changes in HbA1c (R = -0.861, P = 0.006) and body weight (R = -0.895, P = 0.003) in GLP-1RA and SGLT2i trials. The studies using SGLT2i failed to reduce carotid intima media thickness (cIMT), the surrogate marker for atherosclerosis; however, several studies using GLP-1RA successfully reduced cIMT in patients with type 2 diabetes. Compared with SGLT2i, GLP-1RA had a higher probability of decreasing serum triglyceride. GLP-1RA have multiple vascular biological anti-atherogenic properties.

Glucagon-Like Peptide 1 Receptor Agonists Versus Sodium-Glucose Cotransporter 2 Inhibitors for Atherosclerotic Cardiovascular Disease in Patients With Type 2 Diabetes.

Cardiology Research

Viral epidemics or pandemics of acute respiratory infections (ARIs) pose a global threat. Examples are influenza (H1N1) caused by the H1N1pdm09 virus in 2009, severe acute respiratory syndrome (SARS) in 2003, and coronavirus disease 2019 (COVID-19) caused by SARS-CoV-2 in 2019. Antiviral drugs and vaccines may be insufficient to prevent their spread. This is an update of a Cochrane Review last published in 2020. We include results from studies from the current COVID-19 pandemic.

To assess the effectiveness of physical interventions to interrupt or reduce the spread of acute respiratory viruses.

We searched CENTRAL, PubMed, Embase, CINAHL, and two trials registers in October 2022, with backwards and forwards citation analysis on the new studies.

We included randomised controlled trials (RCTs) and cluster-RCTs investigating physical interventions (screening at entry ports, isolation, quarantine, physical distancing, personal protection, hand hygiene, face masks, glasses, and gargling) to prevent respiratory virus transmission.&#xa0; DATA COLLECTION AND ANALYSIS: We used standard Cochrane methodological procedures.

We included 11&#xa0;new RCTs and cluster-RCTs (610,872 participants) in this update, bringing the total number of RCTs to 78. Six of the new trials were conducted during the COVID-19 pandemic; two from Mexico, and one each from Denmark, Bangladesh, England, and Norway. We identified four&#xa0;ongoing studies, of which one is completed, but unreported, evaluating masks concurrent with the COVID-19 pandemic. Many studies were conducted during non-epidemic influenza periods. Several were conducted during the 2009 H1N1 influenza pandemic, and others in epidemic influenza seasons up to 2016. Therefore, many studies were conducted in the context of lower respiratory viral circulation and transmission compared to COVID-19. The included studies were conducted in heterogeneous settings, ranging from suburban schools to hospital wards in high-income countries; crowded inner city settings in low-income countries; and an immigrant neighbourhood in a high-income country. Adherence with interventions was low in many studies. The risk of bias for the RCTs and cluster-RCTs was mostly high or unclear. Medical/surgical masks compared to no masks We included 12 trials (10 cluster-RCTs) comparing medical/surgical masks versus no masks to prevent the spread of viral respiratory illness (two trials with healthcare workers and 10 in the community). Wearing masks in the community probably makes little or no difference to the outcome of influenza-like illness (ILI)/COVID-19 like illness compared to not wearing masks (risk ratio (RR) 0.95, 95% confidence interval (CI) 0.84 to 1.09; 9 trials, 276,917 participants; moderate-certainty evidence. Wearing masks in the community probably makes little or no difference to the outcome of laboratory-confirmed influenza/SARS-CoV-2 compared to not wearing masks (RR 1.01, 95% CI 0.72 to 1.42; 6 trials, 13,919 participants; moderate-certainty evidence). Harms were rarely measured and poorly reported (very low-certainty evidence). N95/P2 respirators compared to medical/surgical masks We pooled trials comparing N95/P2 respirators with medical/surgical masks (four in healthcare settings and one in a household setting). We are very uncertain on the effects of N95/P2 respirators compared with medical/surgical masks on the outcome of clinical respiratory illness (RR 0.70, 95% CI 0.45 to 1.10; 3 trials, 7779 participants; very low-certainty evidence). N95/P2 respirators compared with medical/surgical masks may be effective for ILI (RR 0.82, 95% CI 0.66 to 1.03; 5 trials, 8407 participants; low-certainty evidence). Evidence is limited by imprecision and heterogeneity for these subjective outcomes. The use of a N95/P2 respirators compared to medical/surgical masks probably makes little or no difference for the objective and more precise outcome of laboratory-confirmed influenza infection (RR 1.10, 95% CI 0.90 to 1.34; 5 trials, 8407 participants; moderate-certainty evidence). Restricting pooling to healthcare workers made no difference to the overall findings. Harms were poorly measured and reported, but discomfort wearing medical/surgical masks or N95/P2 respirators was mentioned in several studies (very low-certainty evidence).&#xa0; One previously reported ongoing RCT&#xa0;has now been published and observed that medical/surgical masks were non-inferior to N95 respirators in a large study of 1009 healthcare workers in four countries providing direct care to COVID-19 patients.&#xa0; Hand hygiene compared to control Nineteen trials compared hand hygiene interventions with controls with sufficient data to include in meta-analyses. Settings included&#xa0;schools, childcare centres and homes. Comparing hand hygiene interventions with controls (i.e. no intervention),&#xa0;there was a 14% relative reduction in the number of people with ARIs in the hand hygiene group (RR 0.86, 95% CI 0.81 to 0.90; 9 trials, 52,105 participants; moderate-certainty evidence), suggesting a probable benefit. In absolute terms this benefit would result in a reduction from 380 events per 1000 people to 327 per 1000 people (95% CI 308 to 342). When considering the more strictly defined outcomes of ILI and laboratory-confirmed influenza, the estimates of effect for ILI (RR 0.94, 95% CI 0.81 to 1.09; 11 trials, 34,503 participants; low-certainty evidence), and laboratory-confirmed influenza (RR 0.91, 95% CI 0.63 to 1.30; 8 trials, 8332 participants; low-certainty evidence), suggest the intervention made little or no&#xa0;difference. We pooled 19 trials (71, 210 participants) for the composite outcome of ARI or ILI or influenza, with each study only contributing once and the most comprehensive outcome reported. Pooled data showed that hand hygiene may be beneficial with an 11% relative reduction of respiratory illness (RR 0.89, 95% CI 0.83 to 0.94; low-certainty evidence), but with high heterogeneity. In absolute terms this benefit would result in a reduction from 200 events per 1000 people to 178 per 1000 people (95% CI 166 to 188). Few trials measured and reported harms (very low-certainty evidence). We found no RCTs on gowns and gloves, face shields, or screening at entry ports.

The high risk of bias in the trials, variation in outcome measurement, and relatively low adherence with the interventions during the studies hampers drawing firm conclusions. There were additional RCTs during the pandemic related to physical interventions but a relative paucity given the importance of the question of masking and its relative effectiveness and the concomitant measures of mask adherence which would be highly relevant to the measurement of effectiveness, especially in the elderly and in young children. There is uncertainty about the effects of face masks. The low to moderate certainty of evidence means our confidence in the effect estimate is limited, and that the true effect may be different from the observed estimate of the effect. The pooled results of RCTs did not show a clear reduction in respiratory viral infection with the use of medical/surgical masks. There were no clear differences between the use of medical/surgical masks compared with N95/P2 respirators in healthcare workers when used in routine care to reduce respiratory viral infection. Hand hygiene is likely to modestly reduce the burden of respiratory illness, and although this effect was also present when ILI and laboratory-confirmed influenza were analysed separately, it was not found to be a significant difference for the latter two outcomes. Harms associated with physical interventions were under-investigated. There is a need&#xa0;for large, well-designed RCTs addressing the effectiveness of many of these interventions in multiple settings and populations, as well as the impact of adherence on effectiveness, especially in those most at risk of ARIs.

Physical interventions to interrupt or reduce the spread of respiratory viruses.

Cochrane Database of Systematic Reviews

Fluid resuscitation is typically needed in patients with cirrhosis, sepsis and hypotension. However, the complex circulatory changes associated with cirrhosis with hyperdynamic state, increased splanchnic blood volume and relative central hypovolemia complicates fluid administration and monitoring of fluid status. In patients with advanced cirrhosis, larger volumes of fluids are needed to expand central blood volume and improve sepsis-induced organ hypoperfusion as compared to non-cirrhotic patients, at the cost of further increase in non-central blood volume. Monitoring and targets still need to be defined but echocardiography is promising for bedside assessment of fluid status and responsiveness. Large volumes of saline should be avoided in cirrhosis. Experimental data suggest that independent of volume expansion, albumin is superior to crystalloids at controlling systemic inflammation and preventing acute kidney injury. However, while it is generally accepted that albumin plus antibiotics is superior to antibiotics alone in spontaneous bacterial peritonitis, evidence is lacking in patients with infections other than spontaneous bacterial peritonitis. Patients with advanced cirrhosis, sepsis and hypotension are less likely to be fluid responsive as compared to non-cirrhotic patients and early initiation of vasopressors is recommended. While norepinephrine is the first line option, the role of terlipressin needs to be clarified in this context.

Fluid Resuscitation in Patients with Cirrhosis and Sepsis: A Multidisciplinary Perspective.

Journal of Hepatology

Pulmonary hypertension, defined as an elevation in blood pressure in the pulmonary arteries, is associated with an increased risk of death. The prevalence of pulmonary hypertension is increasing, with an aging population, a rising prevalence of heart and lung disease, and improved pulmonary hypertension survival with targeted therapies. Patients with pulmonary hypertension frequently require noncardiac surgery, although pulmonary hypertension is associated with excess perioperative morbidity and death. This scientific statement provides guidance on the evaluation and management of pulmonary hypertension in patients undergoing noncardiac surgery. We advocate for a multistep process focused on (1) classification of pulmonary hypertension group to define the underlying pathology; (2) preoperative risk assessment that will guide surgical decision-making; (3) pulmonary hypertension optimization before surgery to reduce perioperative risk; (4) intraoperative management of pulmonary hypertension to avoid right ventricular dysfunction and to maintain cardiac output; and (5) postoperative management of pulmonary hypertension to ensure recovery from surgery. Last, this scientific statement highlights the paucity of evidence to support perioperative pulmonary hypertension management and identifies areas of uncertainty and opportunities for future investigation.

The Disulfide Bond between Cys22 and Cys27 in the Protease Domain Modulate Clotting Activity of Coagulation Factor X.

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The Disulfide Bond between Cys22 and Cys27 in the Protease Domain Modulate Clotting Activity of Coagulation Factor X.

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