In spite of recent breakthroughs in understanding limb patterning, the genetic factors determining the differences between the forelimb and the hindlimb have not been understood. The genes Pitx1 and Tbx4 encode transcription factors that are expressed throughout the developing hindlimb but not forelimb buds. Misexpression of Pitx1 in the chick wing bud induced distal expression of Tbx4, as well as HoxC10 and HoxC11, which are normally restricted to hindlimb expression domains. Wing buds in which Pitx1 was misexpressed developed into limbs with some morphological characteristics of hindlimbs: the flexure was altered to that normally observed in legs, the digits were more toe-like in their relative size and shape, and the muscle pattern was transformed to that of a leg.

Role of Pitx1 upstream of Tbx4 in specification of hindlimb identity.

Science

Venous thromboembolism (VTE), particularly portal vein thrombosis, is common in patients with cirrhosis. Misconceptions around the increased bleeding risk in this patient group may lead to delayed and/or inadequate anticoagulation. This nutshell review focusses on the approach to management including the role of direct oral anticoagulants in the treatment of VTE in patients with cirrhosis.

Prevention and management of venous thrombosis in patients with cirrhosis.

British Journal of Haematology

Ventricular arrhythmias associated with mitral valve prolapse (MVP) and the capacity to cause sudden cardiac death (SCD), referred to as 'malignant MVP', are an increasingly recognised, albeit rare, phenomenon. SCD can occur without significant mitral regurgitation, implying an interaction between mechanical derangements affecting the mitral valve apparatus and left ventricle. Risk stratification of these arrhythmias is an important clinical and public health issue to provide precise and targeted management. Evaluation requires patient and family history, physical examination and electrophysiological and imaging-based modalities. We provide a review of arrhythmogenic MVP, exploring its epidemiology, demographics, clinical presentation, mechanisms linking MVP to SCD, markers of disease severity, testing modalities and management, and discuss the importance of risk stratification. Even with recently improved understanding, it remains challenging how best to weight the prognostic importance of clinical, imaging and electrophysiological data to determine a clear high-risk arrhythmogenic profile in which an ICD should be used for the primary prevention of SCD.

Arrhythmogenic Mitral Valve Prolapse: Can We Risk Stratify and Prevent Sudden Cardiac Death?

Arrhythmia & Electrophysiology Review

The management of cardiogenic shock is an ongoing challenge. Despite all efforts and tremendous use of resources, mortality remains high. Whilst reversing the underlying cause, restoring/maintaining organ perfusion and function are cornerstones of management. The presence of comorbidities and preexisting organ dysfunction increases management complexity, aiming to integrate the needs of vital organs in each individual patient. This review provides a comprehensive overview of contemporary literature regarding the definition and classification of cardiogenic shock, its pathophysiology, diagnosis, laboratory evaluation, and monitoring. Further, we distill the latest evidence in pharmacologic therapy and the use of mechanical circulatory support including recently published randomized-controlled trials as well as future directions of research, integrating this within an international group of authors to provide a global perspective. Finally, we explore the need for individualization, especially in the face of neutral randomized trials which may be related to a dilution of a potential benefit of an intervention (i.e., average effect) in this heterogeneous clinical syndrome, including the use of novel biomarkers, artificial intelligence, and machine learning approaches to identify specific endotypes of cardiogenic shock (i.e., subclasses with distinct underlying biological/molecular mechanisms) to support a more personalized medicine beyond the syndromic approach of cardiogenic shock.

Management of cardiogenic shock: state-of-the-art.

Intensive Care Medicine

Autoimmune neuropathies are a heterogeneous group of immune-mediated disorders of the peripheral nerves. Guillain-Barr&#xe9; syndrome (GBS) and chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) are the archetypal acute and chronic forms. Over the past few decades, pathogenic antibodies targeting antigens of the peripheral nervous system and driving peripheral nerve damage in selected patients have been described. Moreover, the detection of these antibodies has diagnostic and therapeutic implications that have prompted a modification of the GBS and CIDP diagnostic algorithms. GBS diagnosis is based in clinical criteria, and systematic testing of anti-ganglioside antibodies is not required. Nonetheless, a positive anti-ganglioside antibody test may support the clinical suspicion when diagnosis of GBS (GM1 IgG), Miller Fisher (GQ1b IgG), or acute sensory-ataxic (GD1b IgG) syndromes is uncertain. Anti-myelin-associated glycoprotein (MAG) IgM and anti-disialosyl IgM antibodies are key in the diagnosis of anti-MAG neuropathy and chronic ataxic neuropathy, ophthalmoplegia, M-protein, cold agglutinins, and disialosyl antibodies spectrum neuropathies, respectively, and help differentiating these conditions from CIDP. Recently, the field has been boosted by the discovery of pathogenic antibodies targeting proteins of the node of Ranvier contactin-1, contactin-associated protein 1, and nodal and paranodal isoforms of neurofascin (NF140, NF186, or NF155). These antibodies define subgroups of patients with specific clinical (most importantly poor or partial response to conventional therapies and excellent response to anti-CD20 therapy) and pathologic (node of Ranvier disruption in the absence of inflammation) features that led to the definition of the "autoimmune nodopathy" diagnostic category and to the incorporation of nodal/paranodal antibodies to clinical routine testing. The purpose of this review was to provide a practical vision for the general neurologist of the use of antibodies in the clinical assessment of autoimmune neuropathies.

Antibodies in Autoimmune Neuropathies: What to Test, How to Test, Why to Test.

Neurology

Since the 1960s, cardiologists have adopted several binary classification systems for acute myocardial infarction (MI) that facilitated improved patient management. Conversely, for chronic stable manifestations of myocardial ischaemia, various classifications have emerged over time, often with conflicting terminology-e.g. 'stable coronary artery disease' (CAD), 'stable ischaemic heart disease', and 'chronic coronary syndromes' (CCS). While the 2019 European guidelines introduced CCS to impart symmetry with 'acute coronary syndromes' (ACS), the 2023 American guidelines endorsed the alternative term 'chronic coronary disease'. An unintended consequence of these competing classifications is perpetuation of the restrictive terms 'coronary' and 'disease', often connoting only a singular obstructive CAD mechanism. It is now important to advance a more broadly inclusive terminology for both obstructive and non-obstructive causes of angina and myocardial ischaemia that fosters conceptual clarity and unifies dyssynchronous nomenclatures across guidelines. We, therefore, propose a new binary classification of 'acute myocardial ischaemic syndromes' and 'non-acute myocardial ischaemic syndromes', which comprises both obstructive epicardial and non-obstructive pathogenetic mechanisms, including microvascular dysfunction, vasospastic disorders, and non-coronary causes. We herein retain accepted categories of ACS, ST-segment elevation MI, and non-ST-segment elevation MI, as important subsets for which revascularization is of proven clinical benefit, as well as new terms like ischaemia and MI with non-obstructive coronary arteries. Overall, such a more encompassing nomenclature better aligns, unifies, and harmonizes different pathophysiologic causes of myocardial ischaemia and should result in more refined diagnostic and therapeutic approaches targeted to the multiple pathobiological precipitants of angina pectoris, ischaemia and infarction.

Myocardial ischaemic syndromes: a new nomenclature to harmonize evolving international clinical practice guidelines.

European Heart Journal

Integrating sodium-glucose co-transporter 2 inhibitors (SGLT2i) into the treatment for chronic kidney disease (CKD) has marked a significant therapeutic advance in nephrology. Clinical trials such as DAPA-CKD and EMPA-KIDNEY have demonstrated the beneficial effects of SGLT2i in slowing CKD progression and reducing proteinuria. However, the applicability of these results to patients with glomerulonephritis is still unresolved due to various limitations. This manuscript combines the evidence supporting the use of SGLT2i in glomerular diseases, highlights the limitations and strikes a conclusive balance on their role in clinical practice.

Sodium glucose co-transporter 2 inhibitors in the treatment of glomerular diseases: a CKJ controversy.

Clinical Kidney Journal

Granulomatosis with polyangiitis (GPA) is a rare systemic disease characterized by granulomatous inflammation of the respiratory tract and necrotizing vasculitis of small and medium vessels often associated with the production of anti-neutrophil cytoplasmic antibodies (ANCA) directed mainly against leukocyte proteinase 3 (PR3). Usually, it involves upper airways, lungs, and kidneys, however any organ may be affected. The diagnosis is based on clinical, radiological, and serological findings. Biopsies, although strongly recommended, are not always feasible and often provides non-specific features. ANCA plays a crucial role in the diagnosis of GPA; nevertheless, ANCA detection is not a substitute for biopsy, which plays an important role in suspected cases, particularly when histological confirmation cannot be obtained. Significant advances have been made in classification criteria and phenotyping of the disease, particularly in determining the nuances between PR3-ANCA and myeloperoxidase (MPO)-ANCA vasculitis. This has led to better characterization of patients and the development of targeted treatment in the future. In addition, better identification of cytokine and immunological profiles may result in immuno-phenotyping becoming a new approach to identify patients with ANCA-associated vasculitis (AAV). Due to the chronic relapsing-remitting nature, strict follow-up of GPA is necessary to provide appropriate management. The search for the accurate marker of disease activity and to predict relapse is still ongoing and no predictor has been found to reliably guide therapeutic decision-making.

Granulomatosis with polyangiitis: clinical characteristics and updates in diagnosis.

Frontiers in Medicine

Antiphospholipid syndrome (APS) is an autoimmune disorder characterized by the presence of antiphospholipid antibodies (aPLs) that predispose individuals to thrombotic events and pregnancy-related complications. APS can occur as a primary condition or in association with other autoimmune diseases, most commonly systemic lupus erythematosus (SLE). Catastrophic APS (CAPS) is a rare, severe variant of APS, marked by rapid-onset, widespread thrombosis leading to multi-organ failure, often triggered by infections, surgical procedures, or cessation of anticoagulation therapy. Both APS and CAPS present significant clinical challenges due to their potential for severe morbidity and mortality. This comprehensive review aims to provide a detailed overview of the pathogenesis, clinical features, diagnostic criteria, and management strategies for APS and CAPS. The review highlights the immunological mechanisms underlying APS, including the role of aPLs, complement system activation, and endothelial cell dysfunction in developing thrombosis. It also outlines the clinical manifestations of APS, such as venous and arterial thrombosis, pregnancy morbidity, and neurological symptoms, along with the diagnostic criteria based on clinical and laboratory findings. The review delves into its pathogenesis, clinical presentation, and diagnostic challenges in the context of CAPS, emphasizing the need for immediate and intensive therapy to manage this life-threatening condition. Current management strategies for APS, including anticoagulant therapy, immunomodulatory treatments, and specific interventions for pregnancy-related complications, are discussed. The review highlights the importance of a multidisciplinary approach for CAPS, combining anticoagulation, high-dose corticosteroids, plasma exchange, and intravenous immunoglobulin. The review also addresses the prognosis and long-term outcomes for patients with APS and CAPS, underlining the necessity for ongoing monitoring and follow-up to prevent recurrent thrombotic events and manage chronic complications. Finally, future directions in research are explored, focusing on emerging therapies, biomarkers for early diagnosis, and the need for clinical trials to advance the understanding and treatment of these complex syndromes. By enhancing the understanding of APS and CAPS, this review aims to improve diagnosis, treatment, and patient care, ultimately leading to better health outcomes for those affected by these conditions.

Antiphospholipid Syndrome and Catastrophic Antiphospholipid Syndrome: A Comprehensive Review of Pathogenesis, Clinical Features, and Management Strategies.

Role of Pitx1 upstream of Tbx4 in specification of hindlimb identity.

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