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BACKGROUND: Early embryonic aortic arches (AA) are a dynamic vascular structures that are in the process of shaping into the great arteries of cardiovascular system. Previously, a time-lapsed mechanosensitive gene expression map was established for AA subject to altered mechanical loads in the avian embryo. To validate this map, we investigated effects on vascular microstructure and material properties following the perturbation of key genes using an in-house microvascular gene knockdown system. RESULTS: All siRNA vectors show a decrease in the expression intensity of desired genes with no significant differences between vectors. In TGFß3 knockdowns, we found a reduction in expression intensities of TGFß3 (≤76%) and its downstream targets such as ELN (≤99.6%), Fbn1 (≤60%), COL1 (≤52%) and COL3 (≤86%) and an increase of diameter in the left AA (23%). MMP2 knockdown also reduced expression levels in MMP2 (≤30%) and a 6-fold increase in its downstream target COL3 with a decrease in stiffness of the AA wall and an increase in the diameter of the AA (55%). These in vivo measurements were confirmed using immunohistochemistry, western blotting and a computational growth model of the vascular extracellular matrix (ECM). CONCLUSIONS: Localized spatial genetic modification of the aortic arch region governs the vascular phenotype and ECM composition of the embryo and can be integrated with mechanically-induced congenital heart disease models.
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Developing a neurovascular bone repair scaffold with an appropriate mechanical strength remains a challenge. Calcium phosphate (CaP) is similar to human bone, but its scaffolds are inherently brittle and inactive, which require recombination with active ions and polymers for bioactivity and suitable strength. This work discussed the synthesis of amorphous magnesium-calcium pyrophosphate (AMCP) and the subsequent development of a humidity-responsive AMCP/cassava starch (CS) scaffold. The scaffold demonstrated enhanced mechanical properties by strengthening the intermolecular hydrogen bonds and ionic bonds between AMCP and CS during the gelatinization and freeze-thawing processes. The release of active ions was rapid initially and stabilized into a long-term stable release after 3 days, which is well-matched with new bone growth. The release of pyrophosphate ions endowed the scaffold with antibacterial properties. At the cellular level, the released active ions simultaneously promoted the proliferation and mineralization of osteoblasts, the proliferation and migration of endothelial cells, and the proliferation of Schwann cells. At the animal level, the scaffold was demonstrated to promote vascular growth and peripheral nerve regeneration in a rat skull defect experiment, ultimately resulting in the significant and rapid repair of bone defects. The construction of the AMCP/CS scaffold offers practical suggestions and references for neurovascular bone repair.
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Regeneração Óssea , Amido , Alicerces Teciduais , Animais , Regeneração Óssea/efeitos dos fármacos , Alicerces Teciduais/química , Ratos , Amido/química , Umidade , Humanos , Proliferação de Células/efeitos dos fármacos , Ratos Sprague-Dawley , Difosfatos/química , Difosfatos/farmacologia , Osteoblastos/efeitos dos fármacos , Osteoblastos/citologia , Pirofosfato de Cálcio/química , Pirofosfato de Cálcio/farmacologia , Células de Schwann/efeitos dos fármacos , Células de Schwann/citologia , Fosfatos de Cálcio/química , Fosfatos de Cálcio/farmacologia , Antibacterianos/química , Antibacterianos/farmacologia , Crânio/efeitos dos fármacosRESUMO
BACKGROUND: Postoperative pulmonary growth in congenital diaphragmatic hernias (CDH) remains unclear. We investigated postoperative pulmonary vascular growth using serial lung perfusion scintigraphy in patients with CDH. METHODS: Neonates with left CDH who underwent surgery and postoperative lung perfusion scintigraphy at our institution between 2001 and 2020 were included. Patient demographics, clinical courses, and lung scintigraphy data were retrospectively analyzed by reviewing medical records. RESULTS: Twenty-one patients with CDH were included. Of these, 10 underwent serial lung scintigraphy. The ipsilateral perfusion rate and median age on the 1st and serial lung scintigraphy were 32% (34 days) and 33% (3.6 years), respectively. Gestational age at prenatal diagnosis (p = 0.02), alveolar-arterial oxygen difference (A-aDO2) at birth (p = 0.007), and preoperative nitric oxide (NO) use (p = 0.014) significantly correlated with the 1st lung scintigraphy. No other variables, including operative approach, were significantly correlated with the 1st or serial scintigraphy findings. All patients improved lung perfusion with serial studies [Difference: + 7.0 (4.3-13.25) %, p = 0.001, paired t-test]. This improvement was not significantly correlated with preoperative A-aDO2 (p = 0.96), NO use (p = 0.28), or liver up (p = 0.90). The difference was significantly larger in patients who underwent thoracoscopic repair than in those who underwent open abdominal repair [+ 10.6 (5.0-17.1) % vs. + 4.25 (1.2-7.9) %, p = 0.042]. CONCLUSION: Our study indicated a postoperative improvement in ipsilateral lung vascular growth, which is possibly enhanced by a minimally invasive approach, in patients with CDH.
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Hérnias Diafragmáticas Congênitas , Pulmão , Humanos , Hérnias Diafragmáticas Congênitas/cirurgia , Hérnias Diafragmáticas Congênitas/diagnóstico por imagem , Estudos Retrospectivos , Feminino , Masculino , Recém-Nascido , Pulmão/diagnóstico por imagem , Pulmão/irrigação sanguínea , Período Pós-Operatório , Imagem de Perfusão/métodos , Pré-EscolarRESUMO
ßIV-spectrin is a membrane-associated cytoskeletal protein that maintains the structural stability of cell membranes and integral proteins such as ion channels and transporters. Its biological functions are best characterized in the brain and heart, although recently we discovered a fundamental new role in the vascular system. Using cellular and genetic mouse models, we reported that ßIV-spectrin acts as a critical regulator of developmental and tumor-associated angiogenesis. ßIV-spectrin was shown to selectively express in proliferating endothelial cells (EC) and suppress VEGF/VEGFR2 signaling by enhancing receptor internalization and degradation. Here we examined how these events impact the downstream kinase signaling cascades and target substrates. Based on quantitative phosphoproteomics, we found that ßIV-spectrin significantly affects the phosphorylation of epigenetic regulatory enzymes in the nucleus, among which DNA methyltransferase 1 (DNMT1) was determined as a top substrate. Biochemical and immunofluorescence results showed that ßIV-spectrin inhibits DNMT1 function by activating ERK/MAPK, which in turn phosphorylates DNMT1 at S717 to impede its nuclear localization. Given that DNMT1 controls the DNA methylation patterns genome-wide, and is crucial for vascular development, our findings suggest that epigenetic regulation is a key mechanism by which ßIV-spectrin suppresses angiogenesis.
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DNA (Citosina-5-)-Metiltransferase 1 , Sistema de Sinalização das MAP Quinases , Proteômica , DNA (Citosina-5-)-Metiltransferase 1/metabolismo , DNA (Citosina-5-)-Metiltransferase 1/genética , Animais , Proteômica/métodos , Camundongos , Fosforilação , Humanos , Neovascularização Fisiológica , Espectrina/metabolismo , Espectrina/genética , Fosfoproteínas/metabolismo , Neovascularização Patológica/metabolismo , Neovascularização Patológica/genética , Células Endoteliais da Veia Umbilical Humana/metabolismo , Células Endoteliais/metabolismo , AngiogêneseRESUMO
PURPOSE: Renal cell carcinoma is an aggressive disease with a high mortality rate. Management has drastically changed with the new era of immunotherapy, and novel strategies are being developed; however, identifying systemic treatments is still challenging. This paper presents an update of the expert panel consensus from the Latin American Cooperative Oncology Group and the Latin American Renal Cancer Group on advanced renal cell carcinoma management in Brazil. METHODS: A panel of 34 oncologists and experts in renal cell carcinoma discussed and voted on the best options for managing advanced disease in Brazil, including systemic treatment of early and metastatic renal cell carcinoma as well as nonclear cell tumours. The results were compared with the literature and graded according to the level of evidence. RESULTS: Adjuvant treatments benefit patients with a high risk of recurrence after surgery, and the agents used are pembrolizumab and sunitinib, with a preference for pembrolizumab. Neoadjuvant treatment is exceptional, even in initially unresectable cases. First-line treatment is mainly based on tyrosine kinase inhibitors (TKIs) and immune checkpoint inhibitors (ICIs); the choice of treatment is based on the International Metastatic Database Consortium (IMCD) risk score. Patients at favourable risk receive ICIs in combination with TKIs. Patients classified as intermediate or poor risk receive ICIs, without preference for ICI + ICIs or ICI + TKIs. Data on nonclear cell renal cancer treatment are limited. Active surveillance has a place in treating favourable-risk patients. Either denosumab or zoledronic acid can be used for treating metastatic bone disease. CONCLUSION: Immunotherapy and targeted therapy are the standards of care for advanced disease. The utilization and sequencing of these therapeutic agents hinge upon individual risk scores and responses to previous treatments. This consensus reflects a commitment to informed decision-making, drawn from professional expertise and evidence in the medical literature.
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Carcinoma de Células Renais , Neoplasias Renais , Humanos , Carcinoma de Células Renais/tratamento farmacológico , Carcinoma de Células Renais/patologia , Neoplasias Renais/tratamento farmacológico , Neoplasias Renais/patologia , América Latina , Consenso , SunitinibeRESUMO
Platelet-rich plasma is an autologous product used in restorative medicine. It contains a high concentration of platelets, which are rich in growth factors and other biologically active substances known for their ability to stimulate regenerative processes in the body. Currently, research is being conducted into the use of platelet-rich plasma in many areas of medicine. This publication provides information on the nature, mechanism of action, therapeutic properties and application of autologous platelet-rich plasma in medicine. Furthermore, ongoing investigations explore its potential in wound healing, orthopedics, dermatology, and even in dentistry, showcasing its versatility and promising outcomes across various medical disciplines. Additionally, the safety and efficacy of platelet-rich plasma therapies are subjects of continual scrutiny, aiming to refine protocols and expand its clinical utility with robust scientific evidence. The growing interest in this regenerative approach underscores its potential as a valuable tool in modern medical practice. Platelet-rich plasma therapy represents a promising avenue for personalized medicine, offering tailored treatment approaches that capitalize on the body's own healing mechanisms to promote tissue repair and regeneration.
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Plasma Rico em Plaquetas , Cicatrização , Humanos , Medicina RegenerativaRESUMO
La participación de los factores antiangiogénicos, la forma soluble de la fms-semejante a la tirosina quinasa (Flt-1s) y la endoglina soluble (Engs), en el desarrollo de la preeclampsia (PE) se ha demostrado en múltiples estudios clínicos y experimentales. Estos estudios están complementados por estudios en animales, en los cuales la sobreexpresión de estos factores antiangiogénicos origina manifestaciones clínicas muy similares a la PE. El origen de esta enfermedad permanece desconocido. Sin embargo, factores genéticos, ambientales e inmunológicos parecen alterar el desarrollo normal de la placenta, lo cual conduce últimamente a la PE. Flt-1s y Engs inhiben la producción y las propiedades proangiogénicas del factor de crecimiento vascular endotelial (FCVE) y del factor de crecimiento placentario (FCP), necesarios para el desarrollo normal vascular de la placenta y las adaptaciones vasculares fisiológicas del embarazo. Cantidades exageradas de Flt-1s y Engs se producen en la placenta disfuncional y se liberan en la circulación materna. Altas concentraciones de Flt-1s y Engs se encuentran en la circulación materna semanas antes de que la enfermedad sea detectada clínicamente. Las capacidades de los factores angiogénicos para predecir PE en embarazos asintomáticos de riesgo bajo y alto son inconsistentes y no útiles para el uso clínico. Por otro lado, proporciones de los factores Flt-1s/FCP, FCP/Flt-1s, y FCP/Eng poseen valores predictivos más altos para diagnosticar PE y predecir sus complicaciones en mujeres con sintomatología de PE. En estas condiciones, el uso clínico de estos marcadores biológicos podría ser implementado en un futuro cercano. Las propiedades biológicas y farmacocinéticas de las estatinas las convierten en uno de los medicamentos con más potencial preventivo para la PE. Otros opciones terapéuticas que se están estudiando son medicamentos que directamente inhiban los factores antiangiogénicos circulantes. Estudios in vitro y estudios pilotos clínicos se están realizando actualmente examinando la seguridad materno-fetal, la transferencia placentaria y la efectividad de estas terapias.
The role of the antiangiogenic factors, the soluble form of the fms-like tyrosine kinase receptor 1 (sFlt1) and the soluble endoglin (sEng), in the development of preeclampsia (PE) has been demonstrated in multiple clinical and experimental studies. These studies are complemented by animal studies, in which overexpression of these antiangiogenic factors leads to clinical manifestations similar to PE. Although, the origin of this disease remains unknown, genetic, environmental, and immunological factors appear to affect the normal placental development, resulting ultimately in PE. sFlt-1 and sEng inhibit the proangiogenic properties of the vascular endothelial growth factor (VEGF) and the placental growth factor (PlGF), affecting the normal vascular development in the placenta and the physiological vascular adaptations that occur in pregnancy. Exaggerated amounts of sFlt-1 and sEng, produced in the dysfunctional placenta, are released into the maternal circulation and elevated circulating concentrations of these antiangiogenic factors are found several weeks prior to the clinical manifestations of the disease. Multiple studies have reported the capacity of circulating antiangiogenic factor concentrations to predict PE in asymptomatic low and high risk pregnancies. The reported predictive values of sFlt-1 and sEng are inconsistent across these studies and therefore their clinical use in this population is not recommended. On the other hand, maternal plasma concentrations of these factors appear to have a better performance in women with symptoms of PE. Among the possible combinations, the ratios of sFlt-1/PlGF, PlGF/sFlt-1, and PlGF/Engs seem to have the highest sensitivities and specificities to diagnose PE as well as the highest predictive values for PE-related adverse outcomes. These properties support their clinical use in this setting and it is likely those ancillary tests will be incorporated to the clinical practice in the near future. The participation of antiangiogenic factors in the pathogenesis of PE, also have stimulated investigation of new targeted therapies. The biological and pharmacokinetic properties of statins have converted them in one of the most promising preventive therapies for this disease. Others are investigating agents that directly inhibit the circulating antiangiogenic factors. In-vitro and pilot clinical studies are currently evaluating the effectiveness, maternal-fetal safety, and placental transference of these therapies.