Among the epimerases specific to alginate, some of them in Azotobacter genera convert &#x3b2;-d-mannuronic acid to &#x3b1;-l-guluronic acid but also have lyase activity to degrade alginate. The remarkable characteristics of these epimerases make it a promising enzyme for tailoring alginates to meet specific demands. Here, we determined the structure of the bifunctional mannuronan C-5 epimerase AlgE3 from Azotobacter chroococcum (AcAlgE3) in complex with several mannuronic acid oligomers as well as in apo form, which allowed us to elucidate the binding manner of each mannuronic acid oligomer, and the structural plasticity, which is dependent on calcium ions. Moreover, a comprehensive analysis of the lyase activity profiles of AcAlgE3 combined with structural characteristics explained the preference for different chain length oligomers.

Structural basis for the minimal bifunctional alginate epimerase AlgE3 from Azotobacter chroococcum.

FEBS Letters

The aim of this review is to summarize available data, including the most recent ones, to help develop the best possible strategy regarding the use of tracheostomy in ICU patients requiring prolonged mechanical ventilation or who experience loss of airway-protecting mechanisms.

Tracheostomy facilitates the weaning process by reducing the patient's work of breathing and increasing comfort. It thus allows for a reduction in sedation levels. It also helps with secretions clearance, facilitates disconnection from the ventilator, and enables earlier phonation, oral intake, and mobilization. Despite these advantages, tracheostomy does not reduce mortality and is associated with both early and late complications, particularly tracheal stenosis. The timing of tracheostomy remains a subject of debate, and only a personalized approach that considers each patient's specific characteristics can help find the best possible compromise between avoiding unnecessary delays and minimizing the risks of performing a needless invasive procedure. In the absence of contraindications, the percutaneous single dilator technique under fibroscopic guidance should be the first choice, but only if the team is properly trained.

A step-by-step individualized approach based on the available evidence allows identifying the best strategy regarding the use of tracheostomy in ICU patients.

Tracheostomy: update on why, when and how.

Current Opinion in Critical Care

From 6% to 8% of patients who present with myocardial infarction have no evidence of obstructive coronary artery disease on angiography. This subgroup tends to be younger, and more of them are women. This review highlights a proposed algorithm to identify the underlying cause of myocardial infarction with nonobstructive coronary arteries (MINOCA). We emphasize the need for a collaborative approach in diagnosing and managing MINOCA to improve patient outcomes, advocating for a standardized diagnostic pathway that incorporates cardiac magnetic resonance imaging and comprehensive clinical evaluation to tailor treatments effectively.

Myocardial infarction with nonobstructive coronary arteries: Current management strategies.

Cleveland Clinic Journal of Medicine

Heart failure is defined as increased intracardiac pressures, either alone or combined with reduced cardiac output. Clinically, it is presented with signs and symptoms of congestion and compensated perfusion. Cardiogenic shock, on the other hand, is the spectrum of hemodynamic disturbances that lead to hypoperfusion or need for circulatory support, due to cardiac disease. Both entities affect millions of people worldwide, have a dismal prognosis, and constitute a severe socioeconomic burden. Heart failure can be the aftermath of ischemic heart disease, hypertension, arrhythmias, or cardiomyopathies. It undergoes multiple classifications, facilitating its investigation and treatment. The pathogenetic mechanisms differ in various types of heart failure, regarding the affected ventricles, the duration of symptoms, and their primary/secondary onset. These mechanisms reflect the complex interactions between cardiopulmonary, vascular, and hepatorenal systems. Acute deterioration of cardiac function can lead to cardiogenic shock. Myocardial infarction accounts for 81% of such cases. Healthy lifestyle and timely management of coronary artery disease are paramount, as they can prevent this life-threatening situation and reduce mortality and the economic burden for healthcare systems. Irrespective of the etiology, cardiogenic shock is interpreted using the pressure-volume loop. This can be modified for each ventricle, the underlying pathophysiology, and the time since symptoms' onset. It therefore provides valuable information about the native circulation and the expected alterations under mechanical or pharmacological support, facilitating the decision-making progress. In 2019, given the phenotypical heterogeneity of cardiogenic shock, the Society for Cardiovascular Angiography and Interventions introduced a classification system. According to this, patients are stratified in five stages proportionally to the severity of their condition. Aside from this classification, various biochemical, imaging, and hemodynamic monitoring indices are used to assess coagulation pathway and cardiac, hepatorenal, and pulmonary function, enabling the heart team to tailor therapy. Additionally, the prognostication progress is facilitated by scores, such as the Observatoire Regional Breton sur l'Infarctus (ORBI) score, the intra-aortic balloon pump (IABP) SHOCK-II score, and the CardShock score, indicating suitable escalation or de-escalation strategies. Despite the current progress, there are several areas of advancement regarding the role of vasoactive drugs in cardiogenic shock, revascularization options, mechanical ventilation patterns, hypothermia treatment, and mechanical circulatory support protocols.

Cardiac Failure and Cardiogenic Shock: Insights Into Pathophysiology, Classification, and Hemodynamic Assessment.

Curēus

Objective: IgA vasculitis (IgAV), previously named as Henoch-Sch&#xf6;nlein purpura, is the most frequent systemic vasculitis in children. In adults, IgAV is less common although it is associated with more severe disease. In fact, the frequency of glomerulonephritis (referred to as IgAV nephritis) in adults is higher than in children and tends to present more severely, with around 10-30% of those affected eventually progressing to end-stage renal disease. In this review, we describe the pathophysiology, main clinical features, diagnosis of the disease, and latest clinical data regarding IgAV therapy. Methods: A narrative literature review, primarily based on articles published in PubMed, was conducted. In addition to discussing the main aspects of glucocorticoids and conventional disease-modifying drugs used in the management of IgAV, this review focuses on the latest information reported regarding biologics and potential future therapies. Results: Glucocorticoids are the first-line therapy for IgAV, especially in adults with severe manifestations. Colchicine, dapsone, and methotrexate can be useful for controlling minor manifestations. Several immunomodulatory agents, such as cyclosporine A, tacrolimus, and mycophenolate mofetil, have shown favorable results as glucocorticoid-sparing agents. Leflunomide has shown promising results but requires further study. The use of rituximab has demonstrated efficacy in reducing relapse frequency, lowering the cumulative glucocorticoid burden, and achieving long-term remission of the disease in children and adults with IgAV. Immunoglobulins and plasma exchange therapy can also be useful in difficult and life-threatening situations. Other potential therapies with encouraging results include TRF-budesonide, B-cell-directed therapy, B-cell-depleting agents, sodium-glucose cotransporter-2 inhibitors, endothelin receptor antagonists, and complement pathway inhibitors. Conclusions: Glucocorticoids are the first-line therapy for IgAV, especially in adults with severe manifestations. The role of various immunomodulatory therapies, such as calcineurin inhibitors and mycophenolate mofetil, remains promising, while rituximab reduces the long-term side effects of glucocorticoids and can help achieve disease remission. Other potential therapies with encouraging results require further research.

IgA Vasculitis (Henoch-Schönlein Purpura): An Update on Treatment.

Journal of Clinical Medicine

The "2024 Guideline for the Primary Prevention of Stroke" replaces the 2014 "Guidelines for the Primary Prevention of Stroke." This updated guideline is intended to be a resource for clinicians to use to guide various prevention strategies for individuals with no history of stroke.

A comprehensive search for literature published since the 2014 guideline; derived from research involving human participants published in English; and indexed in MEDLINE, PubMed, Cochrane Library, and other selected and relevant databases was conducted between May and November 2023. Other documents on related subject matter previously published by the American Heart Association were also reviewed.

Ischemic and hemorrhagic strokes lead to significant disability but, most important, are preventable. The 2024 primary prevention of stroke guideline provides recommendations based on current evidence for strategies to prevent stroke throughout the life span. These recommendations align with the American Heart Association's Life's Essential 8 for optimizing cardiovascular and brain health, in addition to preventing incident stroke. We also have added sex-specific recommendations for screening and prevention of stroke, which are new compared with the 2014 guideline. Many recommendations for similar risk factor prevention were updated, new topics were reviewed, and recommendations were created when supported by sufficient-quality published data.

2024 Guideline for the Primary Prevention of Stroke: A Guideline From the American Heart Association/American Stroke Association.

Stroke; a Journal of Cerebral Circulation

Until recently, major bodies producing guidelines for the management of hypertension in patients with chronic kidney disease (CKD) disagreed in some key issues. In June 2023, the European Society of Hypertension (ESH) published the new 2023 ESH Guidelines for the management of arterial hypertension a document that was endorsed by the European Renal Association. Several novel recommendations relevant to the management of hypertension in patients with CKD appeared in these guidelines, which have been updated to reflect the latest evidence-based practices in managing hypertension in CKD patients. Most of these are in general agreement with the previous 2021 Kidney Disease: Improving Global Outcomes (KDIGO) guidelines-some reflect different emphasis on some topics (i.e. detailed algorithms on antihypertensive agent use) while others reflect evolution of important evidence in recent years. The aim of the present review is to summarize and comment on key points and main areas of focus in patients with CKD, as well as to compare and highlight the main differences with the 2021 KDIGO Guidelines for the management of blood pressure in CKD.

Guidelines for the management of hypertension in CKD patients: where do we stand in 2024?

Clinical Kidney Journal

Metformin was developed from an offshoot of Guanidine. It is known to be the first-line medication for type 2 diabetes mellitus, polycystic ovarian syndrome, and weight reduction. Metformin has also been shown to have effectiveness in the management of non-alcoholic fatty liver disease (NAFLD), liver cirrhosis, and various carcinomas like hepatocellular, colorectal, prostate, breast, urinary bladder, blood, melanoma, bone, skin, lung and so on. This narrative review focuses on the effect of metformin on non-alcoholic fatty liver disease, liver cirrhosis, and hepatocellular carcinoma. The search platforms for the topic were PubMed, Scopus, and Google search engine. Critical words for searching included 'Metformin,' AND 'Indications of Metformin,' AND 'Non-Alcoholic Fatty Liver Disease,' AND 'Metformin mechanism of action,' AND 'NAFLD management,' AND 'NAFLD and inflammation,' AND 'Metformin and insulin,' AND 'Metformin and inflammation,' AND 'Liver cirrhosis,' AND 'Hepatocellular carcinoma.' Lifestyle modification and the use of hypoglycemic agents can help improve liver conditions. Metformin has several mechanisms that enhance liver health, including reducing reactive oxygen species, nuclear factor kappa beta (NF-&#x3ba;B), liver enzymes, improving insulin sensitivity, and improving hepatic cell lipophagy. Long-term use of metformin may cause some adverse effects like lactic acidosis and gastrointestinal disturbance. Metformin long-term overdose may lead to a rise in hydrogen sulfide in liver cells, which calls for pharmacovigilance. Drug regulating authorities should provide approval for further research, and national and international guidelines need to be developed for liver diseases, perhaps with the inclusion of metformin as part of the management regime.

Metformin: Beyond Type 2 Diabetes Mellitus.

The myelodysplastic syndrome (MDS) is considered to be a heterogeneous myeloid malignancy with a common origin in the hematopoietic stem cell compartment, generally divided into lower and higher risk. While treatment goal for lower risk MDS (LR-MDS) is to decrease transfusion burden and transformation into acute leukemia major aim for high risk MDS is to prolong survival and ultimately cure. While novel agents such as luspatercept or imetelstat have recently been approved as new treatment options for LR-MDS, hypomethylating agents (HMA) remain currently the only approved non-transplant option for HR-MDS and is the standard of care for non-transplant-eligible patients. Combinations with other drugs as first-line treatment has to date not proven more efficacious than monotherapy in HR-MDS, and outcome after HMA failure is poor. The only potential cure and standard of care for eligible patients is allogeneic stem cell transplantation (HSCT) and even if the number of transplanted - especially older - MDS patients increased over time due to a better management and donor availability the majority of MDS patients will not be eligible for this curative approach. Current challenges encompass to decrease the relapse risk, the main cause of HSCT failure. This review will summarize current knowledge of options of transplant- and non-transplant treatment approaches for these patients and demonstrate the unmet clinical need for more effective therapies.

Treatment of high risk myelodysplastic syndrome.

Haematologica

Viruses are the most common congenital infections in humans and an important cause of foetal malformations, neonatal morbidity, and mortality. The effects of these infections, which are transmitted in utero (transplacentally), during childbirth or in the puerperium depend on the timing of the infections. These vary from miscarriages (usually with infections in very early pregnancy), congenital malformations (when the infections occur during organogenesis) and morbidity (with infections occurring late in pregnancy, during childbirth or after delivery). The most common of these viruses are cytomegalovirus, hepatitis, herpes simplex type-2, parvovirus B19, rubella, varicella zoster and zika viruses. There are currently very few efficacious antiviral agents licensed for use in pregnancy. For most of these infections, therefore, prevention is mainly by vaccination (where there is a vaccine). The administration of immunoglobulins to those exposed to the virus to offer passive immunity or appropriate measures to avoid being infected would be options to minimise the infections and their consequences. In this review, we discuss some of the congenital and perinatal infections and their consequences on both the mother and fetus and their management focusing mainly on prevention.

Congenital and Perinatal Viral Infections: Consequences for the Mother and Fetus.

Viruses

People with diabetes account for 25% of hospitalizations, or 8 million admissions annually. Poor glycemic control in the hospital is associated with increased morbidity, mortality, length of stay, and readmissions. Key considerations of inpatient diabetes management include initiation of appropriate insulin or medication regimens and frequent dose adjustments based on patient-specific factors. Inpatient diabetes management teams and new technologies are increasingly prevalent and can assist in achieving glycemic targets in the hospital. At discharge, standardized checklists should be used to ensure successful transitions of care.

Structural basis for the minimal bifunctional alginate epimerase AlgE3 from Azotobacter chroococcum.

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Structural basis for the minimal bifunctional alginate epimerase AlgE3 from Azotobacter chroococcum.

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