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Objetivo: Describir las características clínicas de las pacientes con cáncer de ovario epitelial en el Instituto Oncológico Nacional de PanamáÌ. Métodos: Se realizó un estudio descriptivo en el Instituto Oncológico Nacional. Se revisaron todos los expedientes de las pacientes con cáncer de ovario epitelial desde enero 2012 a diciembre 2021. Aquellas con diagnóstico histopatológico confirmado de cáncer de ovario epitelial primario fueron incluidas en el estudio. Entre las variables evaluadas, se encontraban edad, lugar de procedencia, grupo histológico, etapa al diagnóstico, tratamiento y recidivas. Resultados: Se incluyeron 547 pacientes. El 49% (266) de las pacientes residían en la provincia de Panamá. La edad media fue de 56 años (DE:13.2). El 71% (386) estaban aseguradas. El 80% (439) presentaron síntomas relacionados al cáncer. El 80% (442) presentaron valores de CA-125 elevados. El 59% (321) eran de tipo seroso. El 62% (338) fueron tratadas con una combinación de cirugía y quimioterapia. En etapa I, el 19% (27) recayeron mientras que en etapa III, el 39% (103). El 80% (138) de las recidivas recibieron sólo quimioterapia. Conclusiones: En general, el cáncer epitelial se presentó en etapas avanzadas en mujeres mayores de 40 años asociado a sintomatología y valores de CA-125 elevados. El tipo histológico más frecuente fue el seroso y el tratamiento habitual fue una combinación de cirugía y quimioterapia. El porcentaje de muerte fue directamente proporcional con la etapa al diagnóstico. (provisto por Infomedic International)
Objetivo: Describir las características clínicas de las pacientes con cáncer de ovario epitelial en el Instituto Oncológico Nacional de PanamáÌ. Métodos: Se realizó un estudio descriptivo en el Instituto Oncológico Nacional. Se revisaron todos los expedientes de las pacientes con cáncer de ovario epitelial desde enero 2012 a diciembre 2021. Aquellas con diagnóstico histopatológico confirmado de cáncer de ovario epitelial primario fueron incluidas en el estudio. Entre las variables evaluadas, se encontraban edad, lugar de procedencia, grupo histológico, etapa al diagnóstico, tratamiento y recidivas. Resultados: Se incluyeron 547 pacientes. El 49% (266) de las pacientes residían en la provincia de Panamá. La edad media fue de 56 años (DE:13.2). El 71% (386) estaban aseguradas. El 80% (439) presentaron síntomas relacionados al cáncer. El 80% (442) presentaron valores de CA-125 elevados. El 59% (321) eran de tipo seroso. El 62% (338) fueron tratadas con una combinación de cirugía y quimioterapia. En etapa I, el 19% (27) recayeron mientras que en etapa III, el 39% (103). El 80% (138) de las recidivas recibieron sólo quimioterapia. Conclusiones: En general, el cáncer epitelial se presentó en etapas avanzadas en mujeres mayores de 40 años asociado a sintomatología y valores de CA-125 elevados. El tipo histológico más frecuente fue el seroso y el tratamiento habitual fue una combinación de cirugía y quimioterapia. El porcentaje de muerte fue directamente proporcional con la etapa al diagnóstico. (provided by Infomedic International)
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Most protocols used to study the dynamics of calcium (Ca2+) in the malaria parasite are based on dyes, which are invasive and do not allow discrimination between the signal from the host cell and the parasite. To avoid this pitfall, we have generated a parasite line expressing the genetically encoded calcium sensor GCaMP3. The PfGCaMP3 parasite line is an innovative tool for studying spontaneous intracellular Ca2+ oscillations without external markers. Using this parasite line, we demonstrate the occurrence of spontaneous Ca2+ oscillations in the ring, trophozoite, and schizont stages in Plasmodium falciparum. Using the Fourier transform to fluorescence intensity data extracted from different experiments, we observe cytosolic Ca2+ fluctuations. These spontaneous cytosolic Ca2+ oscillations occur in the three intraerythrocytic stages of the parasite, with most oscillations occurring in the ring and trophozoite stages. A control parasite line expressing only a GFP control did not reveal such fluctuations, demonstrating the specificity of the observations. Our results clearly show dynamic, spontaneous Ca2+ oscillations during the asexual stage in P. falciparum, independent from external stimuli.
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To meet the current demand for lead-free piezoelectric ceramics, a novel sol-gel synthesis route is presented for the preparation of Ba0.85Ca0.15Ti0.9Zr0.1O3 doped with cerium (Ce = 0, 0.01, and 0.02 mol%) and vanadium (V = 0, 0.3, and 0.4 mol%). X-ray diffraction patterns reveal the formation of a perovskite phase (space group P4mm) for all samples after calcination at 800 °C and sintering at 1250, 1350, and 1450 °C, where it is proposed that both dopants occupy the B site. Sintering studies show that V doping allows the sintering temperature to be reduced to at least 1250 °C. Undoped BCZT samples sintered at the same temperature show reduced functional properties compared to V-doped samples, i.e., d33 values increase by an order of magnitude with doping. The dissipation factor tan δ decreases with increasing sintering temperature for all doping concentrations, while the Curie temperature TC increases for all V-doped samples, reaching 120 °C for high-concentration co-doped samples. All results indicate that vanadium doping can facilitate the processing of BCZT at lower sintering temperatures without compromising performance while promoting thermal property stability.
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BACKGROUND: Exposure of humans and animals to heavy metals is increasing day-by-day; thus, lead even today remains of significant public health concern. According to CDC, blood lead reference value (BLRV) ranges from 3.5 µg/dl to 5 µg/dl in adults. Recently, almost 2.6% decline in male fertility per year has been reported but the cause is not well established. Lead (Pb2+) affects the size of testis, semen quality, and secretory functions of prostate. But the molecular mechanism(s) of lead toxicity in sperm cells is not clear. Thus, present study was undertaken to evaluate the adverse effects of lead acetate at environmentally relevant exposure levels (0.5, 5, 10 and 20 ppm) on functional and molecular dynamics of spermatozoa of bucks following in vitro exposure for 15 min and 3 h. RESULTS: Lead significantly decreased motility, viable count, and motion kinematic patterns of spermatozoa like curvilinear velocity, straight-line velocity, average path velocity, beat cross frequency and maximum amplitude of head lateral displacement even at 5 ppm concentration. Pb2+ modulated intracellular cAMP and Ca2+ levels in sperm cells through L-type calcium channels and induced spontaneous or premature acrosome reaction (AR) by increasing tyrosine phosphorylation of sperm proteins and downregulated mitochondrial transmembrane potential. Lead significantly increased DNA damage and apoptosis as well. Electron microscopy studies revealed Pb2+ -induced deleterious effects on plasma membrane of head and acrosome including collapsed cristae in mitochondria. CONCLUSIONS: Pb2+ not only mimics Ca2+ but also affects cellular targets involved in generation of cAMP, mitochondrial transmembrane potential, and ionic exchange. Lead seems to interact with Ca2+ channels because of charge similarity and probably enters the sperm cell through these channels and results in hyperpolarization. Our findings also indicate lead-induced TP and intracellular Ca2+ release in spermatozoa which in turn may be responsible for premature acrosome exocytosis which is essential feature of capacitation for fertilization. Thus, lead seems to reduce the fertilizing capacity of spermatozoa even at 0.5 ppm concentrations.
Assuntos
Reação Acrossômica , Acrossomo , Cálcio , Chumbo , Motilidade dos Espermatozoides , Espermatozoides , Masculino , Espermatozoides/efeitos dos fármacos , Cálcio/metabolismo , Motilidade dos Espermatozoides/efeitos dos fármacos , Animais , Acrossomo/efeitos dos fármacos , Chumbo/toxicidade , Reação Acrossômica/efeitos dos fármacos , AMP Cíclico/metabolismo , Bovinos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Análise do Sêmen , Dano ao DNA/efeitos dos fármacos , Compostos Organometálicos/toxicidade , Compostos Organometálicos/farmacologiaRESUMO
Chagas disease vectors can ingest several times their own volume in blood with each meal. This ad libitum feeding causes an intense process of diuresis, inducing the insect to eliminate a large quantity of urine and faeces. To ensure diuresis, the speed of circulation of the haemolymph is increased. The Triatominae circulatory system is quite simple, including the dorsal vessel, which pumps haemolymph in an anterograde direction. The return is caused by peristaltic contractions of the anterior midgut. Triatominae insects can spend several weeks without feeding, meaning that most of the time, the insect is in a resting condition. Although the mechanisms controlling the circulation of the haemolymph during post-prandial diuresis have been largely analysed, the mechanisms controlling it during resting conditions are poorly understood. In this study, we analysed several canonical pathways (i.e. L-type VGCC, GPCR, RyR, IP3R) and a novel system represented by the recently characterized Piezo proteins. Our results show that during the resting condition, haemolymph circulation depends on a cross-talk between myogenic activity, inhibitory and stimulatory cellular messengers, and Piezo proteins. This report also unveils for the first time the existence of a putative Piezo protein in Hemiptera.
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Hemolinfa , Rhodnius , Animais , Rhodnius/fisiologia , Proteínas de Insetos/metabolismo , Insetos Vetores/fisiologia , Doença de Chagas/transmissão , Descanso/fisiologiaRESUMO
In the last two decades, several working groups in the international psychoanalytic community have been interested in the development of systematic tools for psychodynamic diagnosis, case formulation and treatment planning. Such psychodynamic diagnostic manuals are efforts to systematically integrate an enormous and rich amount of historically partialized and dispersed information, but which constitute the substantial contribution of psychoanalysis to the field of mental health. The aim of the present article is to provide an updated review on this kind of systematic tools for diagnosis, case formulation and therapeutic planning, designed for the field of psychodynamic approaches. To this end, we describe the aims and structure of: 1) the Psychodynamic Diagnostic Manual 2 (PDM-2), 2) the Operationalized Psychodynamic Diagnosis (OPD-2/OPD-3) and 3) the Operationalized Psychodynamic Diagnosis for Children and adolescents 2 (OPD-CA-2). The contributions of these current tools to clinical practice and empirical research are discussed, as well as the need to disseminate these types of instruments in our regional context.
En las últimas dos décadas, diversos grupos de trabajo de la comunidad psicoanalítica internacional se han interesado por el desarrollo de herramientas sistemáticas para el diagnóstico, la formulación de los casos y la planificación del tratamiento psicodinámico. Este tipo de manuales diagnósticos psicodinámicos son esfuerzos de integración sistemática de una enorme y rica cantidad de información históricamente parcializada y dispersa, pero que constituye el aporte sustancial del psicoanálisis al campo de la salud mental. El objetivo del presente artículo es ofrecer una revisión actualizada sobre esta clase de herramientas sistemáticas de diagnóstico, formulación del caso y planificación terapéutica, diseñadas para el campo de los abordajes psicodinámicos. A estos fines, se describe la estructura y los objetivos de: 1) el Manual Diagnóstico Psicodinámico 2 (PDM-2), 2) el Diagnóstico Psicodinámico Operacionalizado (OPD-2/OPD-3) y 3) el Diagnóstico Psicodinámico Operacionalizado Infanto-Juvenil 2 (OPD-IJ-2).Se discuten las contribuciones de estas herramientas actuales para la práctica clínica y la investigación empírica, así como la necesidad de difundir este tipo de instrumentos en nuestro contexto regional.
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Transtornos Mentais , Psicoterapia Psicodinâmica , Humanos , Psicoterapia Psicodinâmica/métodos , Transtornos Mentais/terapia , Transtornos Mentais/diagnósticoRESUMO
Lithium therapy received approval during the 1970s, and it has been used for its antidepressant, antimanic, and anti-suicidal effects for acute and long-term prophylaxis and treatment of bipolar disorder (BPD). These properties have been well established; however, the molecular and cellular mechanisms remain controversial. In the past few years, many studies demonstrated that at the cellular level, lithium acts as a regulator of neurogenesis, aging, and Ca2+ homeostasis. At the molecular level, lithium modulates aging by inhibiting glycogen synthase kinase-3ß (GSK-3ß), and the phosphatidylinositol (PI) cycle; latter, lithium specifically inhibits inositol production, acting as a non-competitive inhibitor of inositol monophosphatase (IMPase). Mitochondria and peroxisome proliferator-activated receptor γ coactivator-1α (PGC-1α) have been related to lithium activity, and its regulation is mediated by GSK-3ß degradation and inhibition. Lithium also impacts Ca2+ homeostasis in the mitochondria modulating the function of the lithium-permeable mitochondrial Na+-Ca2+exchanger (NCLX), affecting Ca2+ efflux from the mitochondrial matrix to the endoplasmic reticulum (ER). A close relationship between the protease Omi, GSK-3ß, and PGC-1α has also been established. The purpose of this review is to summarize some of the intracellular mechanisms related to lithium activity and how, through them, neuronal aging could be controlled.
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Senescência Celular , Compostos de Lítio , Neurônios , Neurônios/efeitos dos fármacos , Compostos de Lítio/farmacologia , Fármacos Neuroprotetores/farmacologia , Enzimas/metabolismo , Inositol/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Cálcio/metabolismo , Humanos , Animais , Senescência Celular/efeitos dos fármacosRESUMO
Pannexin1 hemichannels (Panx1 HCs) are found in the membrane of most mammalian cells and communicate the intracellular and extracellular spaces, enabling the passive transfer of ions and small molecules. They are involved in physiological and pathophysiological conditions. During apoptosis, the C-terminal tail of Panx1 is proteolytically cleaved, but the permeability features of hemichannels and their role in cell death remain elusive. To address these topics, HeLa cells transfected with full-length human Panx1 (fl-hPanx1) or C-terminal truncated hPanx1 (Δ371hPanx1) were exposed to alkaline extracellular saline solution, increasing the activity of Panx1 HCs. The Δ371hPanx1 HC was permeable to DAPI and Etd+, but not to propidium iodide, whereas fl-hPanx1 HC was only permeable to DAPI. Furthermore, the cytoplasmic Ca2+ signal increased only in Δ371hPanx1 cells, which was supported by bioinformatics approaches. The influx of Ca2+ through Δ371hPanx1 HCs was necessary to promote cell death up to about 95% of cells, whereas the exposure to alkaline saline solution without Ca2+ failed to induce cell death, and the Ca2+ ionophore A23187 promoted more than 80% cell death even in fl-hPanx1 transfectants. Moreover, cell death was prevented with carbenoxolone or 10Panx1 in Δ371hPanx1 cells, whereas it was undetectable in HeLa Panx1-/- cells. Pretreatment with Ferrostatin-1 and necrostatin-1 did not prevent cell death, suggesting that ferroptosis or necroptosis was not involved. In comparison, zVAD-FMK, a pancaspase inhibitor, reduced death by ~60%, suggesting the involvement of apoptosis. Therefore, alkaline pH increases the activity of Δ371hPanx1HCs, leading to a critical intracellular free-Ca2+ overload that promotes cell death.
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Cálcio , Conexinas , Proteínas do Tecido Nervoso , Humanos , Conexinas/metabolismo , Conexinas/genética , Células HeLa , Cálcio/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Proteínas do Tecido Nervoso/genética , Apoptose , Morte Celular , Sinalização do CálcioRESUMO
Our research aimed to elucidate the mechanism by which aurintricarboxylic acid (ATA) inhibits plasma membrane Ca2+-ATPase (PMCA), a crucial enzyme responsible for calcium transport. Given the pivotal role of PMCA in cellular calcium homeostasis, understanding how it is inhibited by ATA holds significant implications for potentially regulating physiopathological cellular processes in which this pump is involved. Our experimental findings revealed that ATA employs multiple modes of action to inhibit PMCA activity, which are influenced by ATP but also by the presence of calcium and magnesium ions. Specifically, magnesium appears to enhance this inhibitory effect. Our experimental and in-silico results suggest that, unlike those reported in other proteins, ATA complexed with magnesium (ATA·Mg) is the molecule that inhibits PMCA. In summary, our study presents a novel perspective and establishes a solid foundation for future research efforts aimed at the development of new pharmacological molecules both for PMCA and other proteins.
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Ácido Aurintricarboxílico , Cálcio , Magnésio , ATPases Transportadoras de Cálcio da Membrana Plasmática , Magnésio/metabolismo , Magnésio/farmacologia , Ácido Aurintricarboxílico/farmacologia , ATPases Transportadoras de Cálcio da Membrana Plasmática/metabolismo , ATPases Transportadoras de Cálcio da Membrana Plasmática/antagonistas & inibidores , Cálcio/metabolismo , Trifosfato de Adenosina/metabolismo , Membrana Celular/metabolismo , Membrana Celular/efeitos dos fármacos , Animais , HumanosRESUMO
OBJECTIVE: To demonstrate a high-yield molecular diagnostic workflow for lateralized overgrowth (LO), a congenital condition with abnormal enlargement of body parts, and to classify it by molecular genetics. STUDY DESIGN: We categorized 186 retrospective cases of LO diagnosed between 2003 and 2023 into suspected Beckwith-Wiedemann spectrum, PIK3CA-related overgrowth spectrum (PROS), vascular overgrowth, or isolated LO, based on initial clinical assessments, to determine the appropriate first-tier molecular tests and tissue for analysis. Patients underwent testing for 11p15 epigenetic abnormalities or somatic variants in genes related to PI3K/AKT/mTOR, vascular proliferation, and RAS-MAPK cascades using blood or skin DNA. For cases with negative initial tests, a sequential cascade molecular approach was employed to improve diagnostic yield. RESULTS: This approach led to a molecular diagnosis in 54% of cases, 89% of cases consistent with initial clinical suspicions, and 11% reclassified. Beckwith-Wiedemann spectrum was the most common cause, with 43% of cases exhibiting 11p15 abnormalities. PIK3CA-related overgrowth spectrum had the highest confirmation rate, with 74% of clinically diagnosed patients showing a PIK3CA variant. Vascular overgrowth demonstrated significant clinical overlap with other syndromes. A molecular diagnosis of isolated LO proved challenging, with only 21% of cases classifiable into a specific condition. CONCLUSIONS: LO is underdiagnosed from a molecular viewpoint and to date has had no diagnostic guidelines, which is crucial for addressing potential cancer predisposition, enabling precision medicine treatments, and guiding management. This study sheds light on the molecular etiology of LO, highlighting the importance of a tailored diagnostic approach and of selecting appropriate testing to achieve the highest diagnostic yield.
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Síndrome de Beckwith-Wiedemann , Classe I de Fosfatidilinositol 3-Quinases , Humanos , Estudos Retrospectivos , Feminino , Masculino , Classe I de Fosfatidilinositol 3-Quinases/genética , Criança , Pré-Escolar , Síndrome de Beckwith-Wiedemann/genética , Síndrome de Beckwith-Wiedemann/diagnóstico , Lactente , Transtornos do Crescimento/diagnóstico , Transtornos do Crescimento/genética , AdolescenteRESUMO
OBJECTIVE: This study aimed to investigate the effect of Esketamine (ESK) on the Hypoxia/Reoxygenation (H/R) injury of cardiomyocytes by regulating TRPV1 and inhibiting the concentration of intracellular Ca2+. METHODS: The H/R injury model of H9c2 cardiomyocytes was established after 4h hypoxia and 6h reoxygenation. H9c2 cells were treated with different concentrations of ESK or TRPV1 agonist capsaicin (10 µM) or TRPV1 inhibitor capsazepine (1 µM). Cell viability was detected by CCK-8 method, and apoptosis by flow cytometry. Intracellular Ca2+ concentration was evaluated by Fluo-4 AM. LDH, MDA, SOD, and GSH-Px were detected with corresponding commercial kits. TRPV1 and p-TRPV1 proteins were detected by Western blot. RESULTS: After H/R, H9c2 cell viability decreased, apoptosis increased, intracellular Ca2+ concentration increased, LDH and MDA levels increased, SOD and GSH-Px levels decreased, and p-TRPV1 expression increased. ESK treatment rescued these changes induced by H/R. After up-regulating TRPV1, the protective effect of ESK on H/R injury of H9c2 cells was weakened, while down-regulating TRPV1 could further protect against H/R injury. CONCLUSION: ESK alleviates H/R injury of cardiomyocytes by regulating TRPV1 expression and inhibiting intracellular Ca2+ concentration.
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Apoptose , Cálcio , Capsaicina/análogos & derivados , Sobrevivência Celular , Ketamina , Miócitos Cardíacos , Canais de Cátion TRPV , Canais de Cátion TRPV/metabolismo , Canais de Cátion TRPV/efeitos dos fármacos , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Cálcio/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Animais , Ketamina/farmacologia , Traumatismo por Reperfusão Miocárdica/metabolismo , Traumatismo por Reperfusão Miocárdica/tratamento farmacológico , Ratos , Capsaicina/farmacologia , Hipóxia Celular/efeitos dos fármacos , Linhagem Celular , Citometria de Fluxo , Estresse Oxidativo/efeitos dos fármacos , Western BlottingRESUMO
The Cupressaceae family includes species considered to be medicinal. Their essential oil is used for headaches, colds, cough, and bronchitis. Cedar trees like Chamaecyparis lawsoniana (C. lawsoniana) are commonly found in urban areas. We investigated whether C. lawsoniana exerts some of its effects by modifying airway smooth muscle (ASM) contractility. The leaves of C. lawsoniana (363 g) were pulverized mechanically, and extracts were obtained by successive maceration 1:10 (w:w) with methanol/CHCl3. Guinea pig tracheal rings were contracted with KCl, tetraethylammonium (TEA), histamine (HIS), or carbachol (Cch) in organ baths. In the Cch experiments, tissues were pre-incubated with D-600, an antagonist of L-type voltage-dependent Ca2+ channels (L-VDCC) before the addition of C. lawsoniana. Interestingly, at different concentrations, C. lawsoniana diminished the tracheal contractions induced by KCl, TEA, HIS, and Cch. In ASM cells, C. lawsoniana significantly diminished L-type Ca2+ currents. ASM cells stimulated with Cch produced a transient Ca2+ peak followed by a sustained plateau maintained by L-VDCC and store-operated Ca2+ channels (SOCC). C. lawsoniana almost abolished this last response. These results show that C. lawsoniana, and its active metabolite quercetin, relax the ASM by inhibiting the L-VDCC and SOCC; further studies must be performed to obtain the complete set of metabolites of the extract and study at length their pharmacological properties.
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Cálcio , Chamaecyparis , Contração Muscular , Músculo Liso , Extratos Vegetais , Quercetina , Traqueia , Animais , Cobaias , Músculo Liso/efeitos dos fármacos , Músculo Liso/metabolismo , Contração Muscular/efeitos dos fármacos , Quercetina/farmacologia , Quercetina/química , Traqueia/efeitos dos fármacos , Traqueia/metabolismo , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Chamaecyparis/química , Cálcio/metabolismo , Masculino , Bloqueadores dos Canais de Cálcio/farmacologia , Histamina/metabolismo , Canais de Cálcio Tipo L/metabolismo , Folhas de Planta/químicaRESUMO
L-type calcium channels are essential for the excitation-contraction coupling in cardiac muscle. The CaV1.2 channel is the most predominant isoform in the ventricle which consists of a multi-subunit membrane complex that includes the CaV1.2 pore-forming subunit and auxiliary subunits like CaVα2δ and CaVß2b. The CaV1.2 channel's C-terminus undergoes proteolytic cleavage, and the distal C-terminal domain (DCtermD) associates with the channel core through two domains known as proximal and distal C-terminal regulatory domain (PCRD and DCRD, respectively). The interaction between the DCtermD and the remaining C-terminus reduces the channel activity and modifies voltage- and calcium-dependent inactivation mechanisms, leading to an autoinhibitory effect. In this study, we investigate how the interaction between DCRD and PCRD affects the inactivation processes and CaV1.2 activity. We expressed a 14-amino acid peptide miming the DCRD-PCRD interaction sequence in both heterologous systems and cardiomyocytes. Our results show that overexpression of this small peptide can displace the DCtermD and replicate the effects of the entire DCtermD on voltage-dependent inactivation and channel inhibition. However, the effect on calcium-dependent inactivation requires the full DCtermD and is prevented by overexpression of calmodulin. In conclusion, our results suggest that the interaction between DCRD and PCRD is sufficient to bring about the current inhibition and alter the voltage-dependent inactivation, possibly in an allosteric manner. Additionally, our data suggest that the DCtermD competitively modifies the calcium-dependent mechanism. The identified peptide sequence provides a valuable tool for further dissecting the molecular mechanisms that regulate L-type calcium channels' basal activity in cardiomyocytes.
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Canais de Cálcio Tipo L , Miócitos Cardíacos , Canais de Cálcio Tipo L/metabolismo , Canais de Cálcio Tipo L/genética , Canais de Cálcio Tipo L/química , Animais , Miócitos Cardíacos/metabolismo , Humanos , Células HEK293 , Ratos , Domínios ProteicosRESUMO
Background: Sarcomeric hypertrophic cardiomyopathy (HCM) must be differentiated from phenotypically similar conditions because clinical management and prognosis may greatly differ. Patients with unexplained left ventricular hypertrophy require an early, confirmed genetic diagnosis through diagnostic or predictive genetic testing. We tested the feasibility and practicality of the application of a 17-gene next-generation sequencing (NGS) panel to detect the most common genetic causes of HCM and HCM phenocopies, including treatable phenocopies, and report detection rates. Identification of transthyretin cardiac amyloidosis (ATTR-CA) and Fabry disease (FD) is essential because of the availability of disease-specific therapy. Early initiation of these treatments may lead to better clinical outcomes. Methods: In this international, multicenter, cross-sectional pilot study, peripheral dried blood spot samples from patients of cardiology clinics with an unexplained increased left ventricular wall thickness (LVWT) of ≥13 mm in one or more left ventricular myocardial segments (measured by imaging methods) were analyzed at a central laboratory. NGS included the detection of known splice regions and flanking regions of 17 genes using the Illumina NextSeq 500 and NovaSeq 6000 sequencing systems. Results: Samples for NGS screening were collected between May 2019 and October 2020 at cardiology clinics in Colombia, Brazil, Mexico, Turkey, Israel, and Saudi Arabia. Out of 535 samples, 128 (23.9%) samples tested positive for pathogenic/likely pathogenic genetic variants associated with HCM or HCM phenocopies with double pathogenic/likely pathogenic variants detected in four samples. Among the 132 (24.7%) detected variants, 115 (21.5%) variants were associated with HCM and 17 (3.2%) variants with HCM phenocopies. Variants in MYH7 (n=60, 11.2%) and MYBPC3 (n=41, 7.7%) were the most common HCM variants. The HCM phenocopy variants included variants in the TTR (n=7, 1.3%) and GLA (n=2, 0.4%) genes. The mean (standard deviation) ages of patients with HCM or HCM phenocopy variants, including TTR and GLA variants, were 42.8 (17.9), 54.6 (17.0), and 69.0 (1.4) years, respectively. Conclusions: The overall diagnostic yield of 24.7% indicates that the screening strategy effectively identified the most common forms of HCM and HCM phenocopies among geographically dispersed patients. The results underscore the importance of including ATTR-CA (TTR variants) and FD (GLA variants), which are treatable disorders, in the differential diagnosis of patients with increased LVWT of unknown etiology.
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Originally developed as a chemotherapeutic agent, miltefosine (hexadecylphosphocholine) is an inhibitor of phosphatidylcholine synthesis with proven antiparasitic effects. It is the only oral drug approved for the treatment of Leishmaniasis and American Trypanosomiasis (Chagas disease). Although its precise mechanisms are not yet fully understood, miltefosine exhibits broad-spectrum anti-parasitic effects primarily by disrupting the intracellular Ca2+ homeostasis of the parasites while sparing the human hosts. In addition to its inhibitory effects on phosphatidylcholine synthesis and cytochrome c oxidase, miltefosine has been found to affect the unique giant mitochondria and the acidocalcisomes of parasites. Both of these crucial organelles are involved in Ca2+ regulation. Furthermore, miltefosine has the ability to activate a specific parasite Ca2+ channel that responds to sphingosine, which is different to its L-type VGCC human ortholog. Here, we aimed to provide an overview of recent advancements of the anti-parasitic mechanisms of miltefosine. We also explored its multiple molecular targets and investigated how its pleiotropic effects translate into a rational therapeutic approach for patients afflicted by Leishmaniasis and American Trypanosomiasis. Notably, miltefosine's therapeutic effect extends beyond its impact on the parasite to also positively affect the host's immune system. These findings enhance our understanding on its multi-targeted mechanism of action. Overall, this review sheds light on the intricate molecular actions of miltefosine, highlighting its potential as a promising therapeutic option against these debilitating parasitic diseases.
Assuntos
Cálcio , Doença de Chagas , Homeostase , Leishmaniose , Fosforilcolina , Fosforilcolina/análogos & derivados , Humanos , Fosforilcolina/farmacologia , Fosforilcolina/uso terapêutico , Doença de Chagas/tratamento farmacológico , Doença de Chagas/parasitologia , Doença de Chagas/metabolismo , Cálcio/metabolismo , Leishmaniose/tratamento farmacológico , Leishmaniose/metabolismo , Leishmaniose/parasitologia , Homeostase/efeitos dos fármacos , Animais , Antiprotozoários/farmacologia , Antiprotozoários/uso terapêutico , Mitocôndrias/metabolismo , Mitocôndrias/efeitos dos fármacos , Leishmania/efeitos dos fármacos , Leishmania/metabolismo , Trypanosoma cruzi/efeitos dos fármacos , Trypanosoma cruzi/metabolismoRESUMO
Antecedentes: La vía de señalización de la fosfoisitol 3-quinasa (PI3K), que promueve el crecimiento y el metabolismo de las células cancerosas, es la vía mutada con mayor frecuencia en el cáncer de mama y es asociada con quimio resistencia y mal pronóstico. En este estudio presentamos el primer análisis en población panameña y de la región, con ataciones precisas de la mutación PIK3CA, las características clinicopatológicas y pronóstico. Métodos: Estudio exploratorio, donde se recolectaron prospectivamente tumores de 74 pacientes con cáncer de mama metastásico RH+/Her2- del Instituto Oncológico Nacional entre 2022 y 2023. Se realizó un ensayo de PCR en tiempo real para análisis de mutación en ADN extraído del material tumoral fijado en formalina e incluido en parafina para detectar mutaciones en los exones 1, 4, 7, 9 y 20 del gen PIK3CA. Resultados: La mediana de edad de las pacientes estudiadas fue 59 años. La mutación en PIK3CA se encontró en 33.8% (25/74) de pacientes con cáncer de mama, entre ellas 44% fueron mutaciones en el exón 20, 38% en el exón 9, 13% en el exón 4 y 5% en el exón 1. Se observó una correlación significativa entre la mutación y el tener historia de cáncer en la familia (p= 0.005), y en pacientes postmepáusicas (P = 0.045). encontramos asociación entre la mutación y el tipo histológico, grado, tamaño tumoral ni estatus axilar al momento del diagnóstico. La mediana de supervivencia libre de progresión se alcanzó en ambos grupos y tampoco demostró una diferencia significativa. Conclusión: La prevalencia de la mutación es relativamente alta comparada con escenarios internacionales, puede ofrecer una ventaja para elegir las mejores opciones de tratamiento por lo que debe evaluarse de forma rutinaria durante las intervenciones clínicas. (provisto por Infomedic International)
Background: The phosphoisitol 3-kinase (PI3K) signaling pathway, which promotes cancer cell growth and metabolism, is the most frequently mutated pathway in breast cancer and is associated with chemoresistance and poor progsis. In this study we present the first analysis in Panamanian and regional population, with precise antations of the PIK3CA mutation, clinicopathological characteristics and progsis. Methods: Exploratory study, where tumors were prospectively collected from 74 patients with RH+/Her2- metastatic breast cancer from the Instituto Oncológico Nacional between 2022 and 2023. A real-time PCR assay for mutation analysis was performed on DNA extracted from formalin-fixed, paraffin-embedded tumor material to detect mutations in exons 1, 4, 7, 9 and 20 of the PIK3CA gene. Results: The median age of the patients studied was 59 years. The mutation in PIK3CA was found in 33.8% (25/74) of patients with breast cancer, among them 44% were mutations in exon 20, 38% in exon 9, 13% in exon 4 and 5% in exon 1. A significant correlation was observed between the mutation and having history of cancer in the family (P = 0.005), and in postmepausal patients (P = 0.045). We found association between the mutation and histologic type, grade, tumor size or axillary status at diagsis. Median progression-free survival was t reached in both groups and did t show a significant difference. Conclusion: The prevalence of the mutation is relatively high compared to international settings, it may offer an advantage in choosing the best treatment options and should be routinely evaluated during clinical interventions. (provided by Infomedic International)
RESUMO
BACKGROUND: Astrocytes Ca2+ signaling play a central role in the modulation of neuronal function. Activation of metabotropic glutamate receptors (mGluR) by glutamate released during an increase in synaptic activity triggers coordinated Ca2+ signals in astrocytes. Importantly, astrocytes express the Ca2+-dependent nitric oxide (NO)-synthetizing enzymes eNOS and nNOS, which might contribute to the Ca2+ signals by triggering Ca2+ influx or ATP release through the activation of connexin 43 (Cx43) hemichannels, pannexin-1 (Panx-1) channels or Ca2+ homeostasis modulator 1 (CALHM1) channels. Hence, we aim to evaluate the participation of NO in the astrocytic Ca2+ signaling initiated by stimulation of mGluR in primary cultures of astrocytes from rat brain cortex. RESULTS: Astrocytes were stimulated with glutamate or t-ACPD and NO-dependent changes in [Ca2+]i and ATP release were evaluated. In addition, the activity of Cx43 hemichannels, Panx-1 channels and CALHM1 channels was also analyzed. The expression of Cx43, Panx-1 and CALHM1 in astrocytes was confirmed by immunofluorescence analysis and both glutamate and t-ACPD induced NO-mediated activation of CALHM1 channels via direct S-nitrosylation, which was further confirmed by assessing CALHM1-mediated current using the two-electrode voltage clamp technique in Xenopus oocytes. Pharmacological blockade or siRNA-mediated inhibition of CALHM1 expression revealed that the opening of these channels provides a pathway for ATP release and the subsequent purinergic receptor-dependent activation of Cx43 hemichannels and Panx-1 channels, which further contributes to the astrocytic Ca2+ signaling. CONCLUSIONS: Our findings demonstrate that activation of CALHM1 channels through NO-mediated S-nitrosylation in astrocytes in vitro is critical for the generation of glutamate-initiated astrocytic Ca2+ signaling.
Assuntos
Astrócitos , Sinalização do Cálcio , Óxido Nítrico , Animais , Ratos , Astrócitos/metabolismo , Astrócitos/efeitos dos fármacos , Cálcio/metabolismo , Canais de Cálcio/metabolismo , Sinalização do Cálcio/fisiologia , Sinalização do Cálcio/efeitos dos fármacos , Células Cultivadas , Conexina 43/metabolismo , Ácido Glutâmico/metabolismo , Óxido Nítrico/metabolismo , Ratos WistarRESUMO
Chronic kidney disease (CKD) is a prevalent health concern associated with various pathological conditions, including hypertensive nephropathy. Mesangial cells are crucial in maintaining glomerular function, yet their involvement in CKD pathogenesis remains poorly understood. Recent evidence indicates that overactivation of Pannexin-1 (Panx1) channels could contribute to the pathogenesis and progression of various diseases. Although Panx1 is expressed in the kidney, its contribution to the dysfunction of renal cells during pathological conditions remains to be elucidated. This study aimed to investigate the impact of Panx1 channels on mesangial cell function in the context of hypertensive nephropathy. Using an Ang II-infused mouse model and primary mesangial cell cultures, we demonstrated that in vivo exposure to Ang II sensitizes cultured mesangial cells to show increased alterations when they are subjected to subsequent in vitro exposure to Ang II. Particularly, mesangial cell cultures treated with Ang II showed elevated activity of Panx1 channels and increased release of ATP. The latter was associated with enhanced basal intracellular Ca2+ ([Ca2+]i) and increased ATP-mediated [Ca2+]i responses. These effects were accompanied by increased lipid peroxidation and reduced cell viability. Crucially, all the adverse impacts evoked by Ang II were prevented by the blockade of Panx1 channels, underscoring their critical role in mediating cellular dysfunction in mesangial cells. By elucidating the mechanisms by which Ang II negatively impacts mesangial cell function, this study provides valuable insights into the pathogenesis of renal damage in hypertensive nephropathy.
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Fetal growth restriction associated with hypertensive disorders of pregnancy (FGR-HDP) is a prevalent pathology with a higher risk of perinatal morbimortality. In this condition, placental insufficiency and endothelial dysfunction serve key roles. The present prospective cohort study monitored 11 patients with an FGR-HDP and 15 with full-term normotensive pregnancies and studied post-natal intracellular calcium concentration ([Ca2+]i) signals in human umbilical vein endothelial cells (HUVECs). Small fetuses with placental insufficiency were identified using fetal biometry with Doppler velocimetry. Mean gestational age and birth weight were 31.8±4.1 weeks and 1,260±646 g for FGR-HDP and 39.2±0.8 weeks and 3,320±336 g for normal births, respectively. Abnormal umbilical artery Doppler waveforms were found in 64% of neonates with FGR-HDP. A significant percentage (86%) of FGR newborns were admitted to the neonatal intensive care unit at Gustavo Fricke hospital, Viña del Mar, Chile, with one case of death after birth. [Ca2+]i signals were measured by microfluorimetry in Fluo-3-loaded HUVECs from primary cultures. Altered [Ca2+]i signals were observed in HUVECs from FGR-HDP, where the sustained phase of ATP-induced [Ca2+]i responses was significantly reduced compared with the normotensive group. Also, the [Ca2+]i signals induced with 10 mM Ca2+ after depletion of internal Ca2+ stores were significantly higher. The present study provides a better comprehension of the role of altered cytosolic Ca2+ dynamics in endothelial dysfunction and an in vitro model to assess novel therapeutic approaches for decreasing or preventing complications in FGR-HDP.
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Airway smooth muscle (ASM) contraction is determined by the increase in intracellular Ca2+ concentration ([Ca2+]i) caused by its release from the sarcoplasmic reticulum (SR) or by extracellular Ca2+ influx. Major channels involved in Ca2+ influx in ASM cells are L-type voltage-dependent Ca2+ channels (L-VDCCs) and nonselective cation channels (NSCCs). Transient receptor potential vanilloid 4 (TRPV4) is an NSCC recently studied in ASM. Mechanical stimuli, such as contraction, can activate TRPV4. We investigated the possible activation of TRPV4 by histamine (His)- or carbachol (CCh)-induced contraction in guinea pig ASM. In single myocytes, the TRPV4 agonist (GSK101) evoked an increase in [Ca2+]i, characterized by a slow onset and a plateau phase. The TRPV4 antagonist (GSK219) decreased channel activity by 94%, whereas the Ca2+-free medium abolished the Ca2+ response induced by GSK101. Moreover, GSK101 caused Na+ influx in tracheal myocytes. GSK219 reduced the Ca2+ peak and the Ca2+ plateau triggered by His or CCh. TRPV4 blockade shifted the concentration-response curve relating to His and CCh to the right in tracheal rings and reduced the maximal contraction. Finally, the activation of TRPV4 in single myocytes increased the Ca2+ refilling of the SR. We conclude that contraction of ASM cells after stimulation with His or CCh promotes TRPV4 activation, the subsequent influx of Ca2+ and Na+, and the opening of L-VDCCs. The entry of Ca2+ into ASM cells via TRPV4 and L-VDCCs contributes to optimal smooth muscle contraction.