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1.
Arch. argent. pediatr ; 122(4): e202310097, ago. 2024. ilus
Artigo em Inglês, Espanhol | LILACS, BINACIS | ID: biblio-1562722

RESUMO

En la práctica, es muy frecuente asociar las gestaciones gemelares monocoriales (MC) con embarazos complejos o complicados, utilizando ambos términos en forma intercambiable. Sin embargo, no lo son; el dinamismo es protagonista en los sistemas complejos, pero no en los complicados. Para entender a la embarazada con una gestación MC como un sistema complejo, primero se desarrollarán las características principales de los embarazos MC; su placenta es una de las principales responsables de los problemas. Luego se analizará el embarazo MC desde la complejidad, identificando las características del sistema y sus complicaciones como propiedades emergentes.


In practice, it is very common to associate monochorionic (MC) twin pregnancies with complex or complicated pregnancies, using both terms interchangeably. However, these are not synonyms; dynamism is the protagonist in complex systems, but not in complicated ones. In order to understand a MC pregnancy as a complex system, it is necessary to first look into its main characteristics. The placenta is one of the main sources of problems. Then, the MC pregnancy has to be analyzed from the perspective of complexity, identifying the system characteristics and its complications as emergent properties.


Assuntos
Humanos , Feminino , Gravidez , Gêmeos Monozigóticos , Gravidez de Gêmeos/psicologia , Placenta , Complicações na Gravidez , Córion
2.
Acta Ortop Bras ; 32(3): e282286, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39086847

RESUMO

Besides the acute injury and trauma-induced macroscopic alterations, the evolution to posttraumatic ankle osteoarthritis (PTOA) is a complex process progressing at the tissue and molecular level. Furthermore, changes in the molecular pathways affect chondrocyte viability. Treatment modalities for PTOA focal or confined disease include innovative techniques. OBJECTIVE: Our purpose is to increase medical awareness based on scientific evidence of pathophysiology, molecular biology, and treatment of post-traumatic ankle osteoarthritis. METHODS: To support the perspectives of the experts, evidence from the scientific literature respected the PRISMA guidelines and the PICOS search strategy was used. We included case-control, cohort, experimental studies and case reports, written in English. RESULTS: The authors were homogeneously exposed to 282 selected abstracts and 114 full articles directly related to post-traumatic osteoarthritis after malleolar fractures. CONCLUSION: The pathophysiological factors involved in posttraumatic ankle osteoarthritis, such as biological, structural, mechanical, and molecular changes must be studied together, as the interaction between these factors determines the risk of progression of PTOA. Inhibition of a single catabolic molecule or cascade probably is not sufficient to alter the natural progression of the pathological process. Evidence level V, expert opinion.


A evolução para a osteoartrite pós-traumática do tornozelo (PTOA) a partir da lesão aguda e das alterações macroscópicas induzidas pelo trauma é um processo complexo, que progride em nível tecidual e molecular. Além disso, as alterações nas vias moleculares afetam a viabilidade dos condrócitos. As modalidades focais ou confinadas de tratamento para PTOA incluem técnicas inovadoras. Objetivo: Nosso objetivo é aumentar a conscientização médica, com base em evidências científicas de fisiopatologia, biologia molecular e tratamento da osteoartrite pós-traumática do tornozelo. Métodos: Para o embasamento das perspectivas dos autores experts, as evidências da literatura científica respeitaram as diretrizes Prisma e a estratégia de busca Picos foi empregada. Incluímos estudos de caso-controle, de coorte, experimentais e relatos de caso, escritos em inglês. Resultados: Os autores foram expostos de forma homogênea a 282 resumos e 114 artigos completos, diretamente relacionados à osteoartrite pós-traumática após fraturas maleolares. Conclusão: Os fatores fisiopatológicos envolvidos na osteoartrite pós-traumática do tornozelo, como alterações biológicas, estruturais, mecânicas e moleculares, devem ser estudados em conjunto, pois a interação entre esses fatores determina o risco de progressão da PTOA. A inibição de uma única molécula catabólica ou cascata provavelmente não é suficiente para alterar a progressão natural do processo patológico. Nível de evidência V, opinião do especialista.

3.
Int J Mol Sci ; 25(14)2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-39062815

RESUMO

Preeclampsia (PE) is a multifactorial pregnancy disorder characterized by hypertension and proteinuria, posing significant risks to both maternal and fetal health. Despite extensive research, its complex pathophysiology remains incompletely understood. This narrative review aims to elucidate the intricate mechanisms contributing to PE, focusing on abnormal placentation, maternal systemic response, oxidative stress, inflammation, and genetic and epigenetic factors. This review synthesizes findings from recent studies, clinical trials, and meta-analyses, highlighting key molecular and cellular pathways involved in PE. The review integrates data on oxidative stress biomarkers, angiogenic factors, immune interactions, and mitochondrial dysfunction. PE is initiated by poor placentation due to inadequate trophoblast invasion and improper spiral artery remodeling, leading to placental hypoxia. This triggers the release of anti-angiogenic factors such as soluble fms-like tyrosine kinase-1 (sFlt-1) and soluble endoglin (sEng), causing widespread endothelial dysfunction and systemic inflammation. Oxidative stress, mitochondrial abnormalities, and immune dysregulation further exacerbate the condition. Genetic and epigenetic modifications, including polymorphisms in the Fms-like tyrosine kinase 1 (FLT1) gene and altered microRNA (miRNA) expression, play critical roles. Emerging therapeutic strategies targeting oxidative stress, inflammation, angiogenesis, and specific molecular pathways like the heme oxygenase-1/carbon monoxide (HO-1/CO) and cystathionine gamma-lyase/hydrogen sulfide (CSE/H2S) pathways show promise in mitigating preeclampsia's effects. PE is a complex disorder with multifactorial origins involving abnormal placentation, endothelial dysfunction, systemic inflammation, and oxidative stress. Despite advances in understanding its pathophysiology, effective prevention and treatment strategies remain limited. Continued research is essential to develop targeted therapies that can improve outcomes for both mothers and their babies.


Assuntos
Estresse Oxidativo , Pré-Eclâmpsia , Humanos , Pré-Eclâmpsia/fisiopatologia , Pré-Eclâmpsia/metabolismo , Gravidez , Feminino , Epigênese Genética , Inflamação/metabolismo , Biomarcadores , Placenta/metabolismo , Placenta/fisiopatologia , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/genética
4.
J Physiol ; 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39018163

RESUMO

Heart failure (HF) is a heterogeneous condition that can be categorized according to the left ventricular ejection fraction (EF) into HF with reduced (HFrEF) or preserved (HFpEF) EF. Although HFrEF and HFpEF share some common clinical manifestations, the mechanisms underlying each phenotype are often found to be distinct. Identifying shared and divergent pathophysiological features might expand our insights on HF pathophysiology and assist the search for therapies for each HF subtype. In this study, we evaluated and contrasted two new murine models of non-ischaemic HFrEF and cardiometabolic HFpEF in terms of myocardial structure, left ventricular function, gene expression, cardiomyocyte calcium handling, mitochondrial polarization and protein acetylation in a head-to-head fashion. We found that in conditions of similar haemodynamic stress, the HFrEF myocardium underwent a more pronounced hypertrophic and fibrotic remodelling, whereas inflammation was greater in the HFpEF myocardium. We observed opposing features on calcium release, which was diminished in the HFrEF cardiomyocyte but enhanced in the HFpEF cardiomyocyte. Mitochondria were less polarized in both HFrEF and HFpEF cardiomyocytes, reflecting similarly impaired metabolic capacity. Hyperacetylation of cardiac proteins was observed in both models, but it was more accentuated in the HFpEF heart. Despite shared features, unique triggering mechanisms (neurohormonal overactivation in HFrEF vs. inflammation in HFpEF) appear to determine the distinct phenotypes of HF. The findings of the present research stress the need for further exploration of the differential mechanisms underlying each HF subtype, because they might require specific therapeutic interventions. KEY POINTS: The mechanisms underlying heart failure with either reduced (HFrEF) or preserved (HFpEF) ejection fraction are often found to be different. Previous studies comparing pathophysiological traits between HFrEF and HFpEF have been conducted on animals of different ages and strains. The present research contrasted two age-matched mouse models of non-ischaemic HFrEF and cardiometabolic HFpEF to uncover divergent and shared features. We found that upon similar haemodynamic stress, the HFrEF heart experienced a more pronounced hypertrophic and fibrotic remodelling, whereas inflammation appeared to be greater in the HFpEF myocardium. Calcium release was diminished in the HFrEF cardiomyocyte and enhanced in the HFpEF cardiomyocyte. Mitochondria were comparably less polarized in both HFrEF and HFpEF myocytes. Hyperacetylation of proteins was common to both models, but stronger in the HFpEF heart. Casting light on common and distinguishing features might ease the quest for phenotype-specific therapies for heart failure patients.

5.
Front Immunol ; 15: 1363572, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38911850

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is responsible for the respiratory distress condition known as COVID-19. This disease broadly affects several physiological systems, including the gastrointestinal, renal, and central nervous (CNS) systems, significantly influencing the patient's overall quality of life. Additionally, numerous risk factors have been suggested, including gender, body weight, age, metabolic status, renal health, preexisting cardiomyopathies, and inflammatory conditions. Despite advances in understanding the genome and pathophysiological ramifications of COVID-19, its precise origins remain elusive. SARS-CoV-2 interacts with a receptor-binding domain within angiotensin-converting enzyme 2 (ACE2). This receptor is expressed in various organs of different species, including humans, with different abundance. Although COVID-19 has multiorgan manifestations, the main pathologies occur in the lung, including pulmonary fibrosis, respiratory failure, pulmonary embolism, and secondary bacterial pneumonia. In the post-COVID-19 period, different sequelae may occur, which may have various causes, including the direct action of the virus, alteration of the immune response, and metabolic alterations during infection, among others. Recognizing the serious adverse health effects associated with COVID-19, it becomes imperative to comprehensively elucidate and discuss the existing evidence surrounding this viral infection, including those related to the pathophysiological effects of the disease and the subsequent consequences. This review aims to contribute to a comprehensive understanding of the impact of COVID-19 and its long-term effects on human health.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , COVID-19/imunologia , COVID-19/epidemiologia , Enzima de Conversão de Angiotensina 2/metabolismo , Pandemias
7.
Vet Res Commun ; 48(4): 2243-2261, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38717733

RESUMO

Canine leishmaniasis (CanL) caused by Leishmania infantum commonly progresses with renal and ophthalmic lesions associated with active systemic disease. As chronic inflammation related to immune complex deposits is a pathophysiological factor in the development of both glomerulonephritis and uveitis, we aimed to evaluate renal and ocular histopathological lesions and analyze whether they were related to each other and the clinical degree of the disease. For that, we evaluated 15 dogs from CanL-endemic areas. L. infantum PCR-positive dogs were studied according to disease severity into two different groups: Group-1 (G1) had data from seven dogs with mild to moderate CanL and no history of treatment, and G2 was formed with eight dogs with severe to terminal disease that had not responded to CanL treatment. Histopathological analysis of kidneys showed higher frequencies and intensities of glomerular basement membrane thickening (p = 0.026), deposits in glomeruli (p = 0.016), epithelial necrosis (p = 0.020), tubular dilatation (p = 0.003) and interstitial fibrosis (p = 0.04) in G2 dogs than in G1 dogs. Surprisingly, the histopathology of eye bulbs showed a higher frequency and intensity of retinitis (p = 0.019) in G1 dogs than in G2 dogs. The comparative analysis showed that there was no correspondence between histopathological findings in kidneys versus eyes in milder or more severe CanL. Our findings suggested that (1) clinically undetectable eye alterations can be more precocious than those in kidneys in the development of CanL, and (2) the lower frequency of eye lesions and higher frequency of renal lesions in dogs with terminal disease even after treatment indicate that therapy may have been effective in reducing CanL-associated ophthalmic disease but not proportionally in reducing kidney disease.


Assuntos
Doenças do Cão , Rim , Leishmania infantum , Leishmaniose Visceral , Animais , Cães , Doenças do Cão/patologia , Doenças do Cão/parasitologia , Masculino , Rim/patologia , Rim/parasitologia , Leishmaniose Visceral/veterinária , Leishmaniose Visceral/patologia , Leishmaniose Visceral/parasitologia , Feminino , Olho/patologia , Olho/parasitologia
8.
World Allergy Organ J ; 17(5): 100906, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38818086

RESUMO

Hereditary angioedema (HAE) encompasses a group of diseases characterized by recurrent, genetically mediated angioedema associated with increased vascular permeability primarily due to bradykinin. The disease poses diagnostic challenges, leading to underdiagnosis and delayed therapy. Severe manifestations include laryngeal and intestinal angioedema, contributing to significant morbidity and mortality. If left undiagnosed, the estimated mortality rate of the disease ranges from 25% to 40% due to asphyxiation caused by laryngeal angioedema. There is a pressing need to enhance awareness of hereditary angioedema and its warning signs. The acronym "H4AE" may facilitate the memorization of these signs. This study comprehensively reviews clinical, laboratory, and physiopathological features of documented HAE subtypes. The study advocates for an improved HAE classification based on endotypes, building on the knowledge of angioedema pathophysiology. The proposed endotype classification of HAE offers a clear and applicable framework, encouraging advancements in disease understanding and classification.

9.
Chron Respir Dis ; 21: 14799731241251827, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38717428

RESUMO

Asthma and obstructive sleep apnea (OSA) are common respiratory disorders. They share characteristics such as airway obstruction, poor sleep quality, and low quality of life. They are often present as comorbidities, along with obesity, gastroesophageal reflux disease (GERD), and allergic rhinitis (AR), which impacts the disease's control. In recent years, there has been discussion about the association between these conditions and their pathophysiological and clinical consequences, resulting in worse health outcomes, increased healthcare resource consumption, prolonged hospital stays, and increased morbidity and mortality. Some studies demonstrate that treatment with continuous positive airway pressure (CPAP) can have a beneficial effect on both pathologies. This review summarizes the existing evidence of the association between asthma and OSA at their pathophysiological, epidemiological, clinical, and therapeutic levels. It intends to raise awareness among healthcare professionals about these conditions and the need for further research.


Assuntos
Asma , Pressão Positiva Contínua nas Vias Aéreas , Refluxo Gastroesofágico , Apneia Obstrutiva do Sono , Humanos , Apneia Obstrutiva do Sono/terapia , Apneia Obstrutiva do Sono/epidemiologia , Asma/terapia , Asma/epidemiologia , Asma/complicações , Pressão Positiva Contínua nas Vias Aéreas/métodos , Refluxo Gastroesofágico/terapia , Refluxo Gastroesofágico/epidemiologia , Rinite Alérgica/terapia , Rinite Alérgica/complicações , Rinite Alérgica/epidemiologia , Comorbidade , Obesidade/complicações , Obesidade/terapia , Obesidade/epidemiologia , Qualidade de Vida , Assistência Integral à Saúde/métodos
10.
Front Physiol ; 15: 1403211, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38651041
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