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PURPOSE: Breast cancer patients referred to genetic counseling often undergo genetic testing with broad panels that include both breast cancer susceptibility genes as well as genes more specific for extramammary sites. As a result, patients are often incidentally found to have germline mutations in genes that are not necessarily related to breast cancer risk. One such gene is MUTYH. To understand the role MUTYH may play in breast cancer, the clinicopathological features of patients with monoallelic MUTYH germline mutation and breast cancer were examined. METHODS: The clinicopathological characteristics of the breast cancers from patients with monoallelic MUTYH mutation were compared to breast cancer patients with other germline mutations in known breast cancer susceptibility genes, including ATM, BRCA1/2, CHEK2, and PALB2. The breast cancer patients who received genetic counseling but tested negative for the aforementioned gene mutations were used as a control group. RESULTS: Histologic characteristics of the breast cancers arising in monoallelic MUTYH mutation carriers had significantly larger tumor size, higher tumor grade, and more high-risk biomarker profiles (i.e., Her2-positive and triple-negative) than breast cancer patients with susceptibility genes, except for BRCA1. MUTYH mutation carriers also showed a trend of more frequent intratumoral divergency in terms of tumor grade and biomarker profiles. CONCLUSION: Although germline monoallelic MUTYH mutation is not thought to confer a meaningfully increased risk of breast cancer development, it may contribute to pathological aggressiveness and diversity of breast cancers when they sporadically arise in MUTYH carriers.
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Neoplasias da Mama , Feminino , Humanos , Biomarcadores , Proteína BRCA1/genética , Proteína BRCA2/genética , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Predisposição Genética para Doença , Mutação em Linhagem Germinativa , MutaçãoRESUMO
There is an urgent need to understand severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-host interactions involved in virus spread and pathogenesis, which might contribute to the identification of new therapeutic targets. In this study, we investigated the presence of SARS-CoV-2 in postmortem lung, kidney, and liver samples of patients who died with coronavirus disease (COVID-19) and its relationship with host factors involved in virus spread and pathogenesis, using microscopy-based methods. The cases analyzed showed advanced stages of diffuse acute alveolar damage and fibrosis. We identified the SARS-CoV-2 nucleocapsid (NC) in a variety of cells, colocalizing with mitochondrial proteins, lipid droplets (LDs), and key host proteins that have been implicated in inflammation, tissue repair, and the SARS-CoV-2 life cycle (vimentin, NLRP3, fibronectin, LC3B, DDX3X, and PPARγ), pointing to vimentin and LDs as platforms involved not only in the viral life cycle but also in inflammation and pathogenesis. SARS-CoV-2 isolated from a patient´s nasal swab was grown in cell culture and used to infect hamsters. Target cells identified in human tissue samples included lung epithelial and endothelial cells; lipogenic fibroblast-like cells (FLCs) showing features of lipofibroblasts such as activated PPARγ signaling and LDs; lung FLCs expressing fibronectin and vimentin and macrophages, both with evidence of NLRP3- and IL1ß-induced responses; regulatory cells expressing immune-checkpoint proteins involved in lung repair responses and contributing to inflammatory responses in the lung; CD34+ liver endothelial cells and hepatocytes expressing vimentin; renal interstitial cells; and the juxtaglomerular apparatus. This suggests that SARS-CoV-2 may directly interfere with critical lung, renal, and liver functions involved in COVID-19-pathogenesis.
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COVID-19 , Humanos , COVID-19/patologia , Fibronectinas , Vimentina , SARS-CoV-2 , Células Endoteliais , Proteína 3 que Contém Domínio de Pirina da Família NLR , PPAR gama , Pulmão , Inflamação/patologia , Rim , FígadoRESUMO
BACKGROUND: It is unknown whether an incident cancer diagnosis differentially impacts acute and long-term memory aging between older White and Black Americans. METHODS: Incident cancer diagnoses and memory (immediate and delayed recall, combined with proxy-reported memory) were assessed at biennial study interviews in the US Health and Retirement Study (N=14,235, 1998-2016). We used multivariable segmented linear mixed-effects models to evaluate the rate of change in standardized memory score (SD/decade) in the years before, acutely at the time of, and in the years following an incident cancer diagnosis, compared to cancer-free adults, by race. RESULTS: Black participants experienced faster memory decline than White participants (cancer-free group: -1.211 vs. -1.077; P<0.0001). An incident cancer diagnosis was associated with an acute memory drop in White, but not Black participants (-0.065 vs. 0.024; P<0.0001). However, White cancer survivors experienced slower memory decline than cancer-free White adults before and after diagnosis, but this memory advantage was not observed among Black cancer survivors. CONCLUSIONS: Racial disparities in memory aging are not modified by an incident cancer diagnosis. The acute cancer-related memory decline and long-term memory advantage experienced by White, but not Black, cancer survivors relative to cancer-free older adults, requires further investigation.
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Negro ou Afro-Americano , Neoplasias , Idoso , Envelhecimento , Humanos , Transtornos da Memória/diagnóstico , Neoplasias/diagnósticoRESUMO
CIGB-247 is a vascular endothelial growth factor (VEGF)-based active immunotherapy and it is currently under investigation for cancer treatment. This specific active immunotherapy encompasses two vaccine candidates that use a human VEGF variant molecule as antigen, in combination with two clinically tested adjuvants: VSSP or aluminum phosphate. CIGB-247 has been evaluated in patients with advanced solid tumors, recruited in two phase I clinical trials, and it has been shown to be safe and immunogenic by activating both cellular and humoral immune responses against human VEGF. The immunization induces specific IgG antibodies, and also shows as effect, the reduction of free-VEGF levels within platelets (platelet-derived free VEGF). The production of systemic IgG antibodies and the presence of VEGF in another compartment, almost exclusively within platelets, have arisen some questions about this effect detected in the vaccinated-cancer patients. Based on some relevant published works about platelet endocytosis and VEGF pharmacodynamics during bevacizumab treatment as well as the phase I clinical data of CIGB-247, this investigation aims to hypothesize and analyze the potential mechanisms involved in the reduction of platelet-derived free VEGF as a result of vaccination with CIGB-247.Abbreviations: FcγR: Fc gamma receptors; IC: immune complexes; VEGF: vascular endothelial growth factor; VEGFR1: vascular endothelial growth factor receptor 1; VEGFR2: vascular endothelial growth factor receptor 2.
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Vacinas Anticâncer , Neoplasias , Humanos , Imunoglobulina G , Imunoterapia Ativa , Neoplasias/terapia , Fator de Crescimento Derivado de Plaquetas , Fator A de Crescimento do Endotélio Vascular/metabolismo , Receptor 1 de Fatores de Crescimento do Endotélio VascularRESUMO
Gestational long-term hypoxia increases the risk of myriad diseases in infants including persistent pulmonary hypertension. Similar to humans, fetal lamb lung development is susceptible to long-term intrauterine hypoxia, with structural and functional changes associated with the development of pulmonary hypertension including pulmonary arterial medial wall thickening and dysregulation of arterial reactivity, which culminates in decreased right ventricular output. To further explore the mechanisms associated with hypoxia-induced aberrations in the fetal sheep lung, we examined the premise that metabolomic changes and functional phenotypic transformations occur due to intrauterine, long-term hypoxia. To address this, we performed electron microscopy, Western immunoblotting, calcium imaging, and metabolomic analyses on pulmonary arteries isolated from near-term fetal lambs that had been exposed to low- or high-altitude (3,801 m) hypoxia for the latter 110+ days of gestation. Our results demonstrate that the sarcoplasmic reticulum was swollen with high luminal width and distances to the plasma membrane in the hypoxic group. Hypoxic animals were presented with higher endoplasmic reticulum stress and suppressed calcium storage. Metabolically, hypoxia was associated with lower levels of multiple omega-3 polyunsaturated fatty acids and derived lipid mediators (e.g., eicosapentaenoic acid, docosahexaenoic acid, α-linolenic acid, 5-hydroxyeicosapentaenoic acid (5-HEPE), 12-HEPE, 15-HEPE, prostaglandin E3, and 19(20)-epoxy docosapentaenoic acid) and higher levels of some omega-6 metabolites (P < 0.02) including 15-keto prostaglandin E2 and linoleoylglycerol. Collectively, the results reveal broad evidence for long-term hypoxia-induced metabolic reprogramming and phenotypic transformations in the pulmonary arteries of fetal sheep, conditions that likely contribute to the development of persistent pulmonary hypertension.
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Reprogramação Celular , Hipóxia Fetal/fisiopatologia , Feto/fisiopatologia , Hipóxia/fisiopatologia , Metaboloma , Efeitos Tardios da Exposição Pré-Natal/fisiopatologia , Artéria Pulmonar/fisiopatologia , Altitude , Animais , Cálcio , Feminino , Idade Gestacional , Gravidez , OvinosRESUMO
Cancer diagnoses are associated with better long-term memory in older adults, possibly reflecting a range of social confounders that increase cancer risk but improve memory. We used spouse's memory as a negative control outcome to evaluate this possible confounding, since spouses share social characteristics and environments, and individuals' cancers are unlikely to cause better memory among their spouses. We estimated the association of an individual's incident cancer diagnosis (exposure) with their own (primary outcome) and their spouse's (negative control outcome) memory decline in 3601 couples from 1998 to 2014 in the Health and Retirement Study, using linear mixed-effects models. Incident cancer predicted better long-term memory for the diagnosed individual. We observed no association between an individual's cancer diagnosis and rate of spousal memory decline. This negative control study suggests that the inverse association between incident cancer and rate of memory decline is unlikely to be attributable to social/behavioral factors shared between spouses.
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Memória/fisiologia , Neoplasias/diagnóstico , Cônjuges/estatística & dados numéricos , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos e QuestionáriosRESUMO
BACKGROUND: CIGB-247 is a cancer therapeutic vaccine that uses as antigen a variant of human vascular endothelial growth factor (VEGF) mixed with the bacterially-derived adjuvant VSSP. CIGB-247 has been already evaluated in two phase I clinical trials (CENTAURO and CENTAURO-2), showing to be safe and immunogenic in advanced cancer patients selected under well-defined and controlled clinical conditions. Surviving patients were submitted to monthly re-immunizations and some of them showed objective clinical benefits. Based on these results, a compassionate use program (CUP) with CIGB-247 was initiated for patients that did not meet the strict entry criteria applied for the CENTAURO and CENTAURO-2 clinical trials, but could potentially benefit from the application of this cancer therapeutic vaccine. RESULTS: Polyclonal IgM, IgA and IgG antibodies specific for VEGF were detected by ELISA in serum samples from patients vaccinated with 400 µg of antigen combined with 200 µg of VSSP. Polyclonal antibody response showed no cross reactivity for other VEGF family member molecules like VEGF-C and VEGF-D. Serum from immunized individuals was able to block the binding of VEGF to its receptors VEGFR2 and VEGFR1. IgG fraction purified from immune sera shared the aforementioned characteristics and also inhibited the interaction between VEGF and the therapeutic recombinant antibody bevacizumab, an anti-angiogenic drug approved for the treatment of different tumors. No serious adverse events attributable to CIGB-247 have been documented yet in participants of the CIGB-247 CUP. The present paper is a first report of our findings concerning the humoral response and safety characteristics in treated CIGB-247 CUP cancer patients. The study has provided the unique opportunity of not only testing CIGB-247 in a broader clinical spectrum sample of Cuban cancer patients, but also within the context of the day-to-day clinical practice and treatment settings for these diseases in Cuban medical institutions. CONCLUSIONS: The CIGB-247 CUP has demonstrated that immunization and follow-up of a variety of cancer patients, under day-to-day clinical practice conditions in several Cuban medical institutions, replicate our previous findings in clinical trials: CIGB-247 is safe and immunogenic.
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Vacinas Anticâncer/imunologia , Imunoterapia Ativa/métodos , Neoplasias/imunologia , Proteolipídeos/imunologia , Fator A de Crescimento do Endotélio Vascular/imunologia , Adjuvantes Imunológicos , Ensaios de Uso Compassivo , Feminino , Humanos , Imunidade Humoral , Imunoglobulina A/sangue , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Masculino , Pessoa de Meia-Idade , Neoplasias/terapia , Resultado do Tratamento , Vacinação , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismoRESUMO
INTRODUCTION: We evaluated whether competing risk of death or selective survival could explain the reported inverse association between cancer history and dementia incidence (incidence rate ratio [IRR] ≈ 0.62-0.85). METHODS: A multistate simulation model of a cancer- and dementia-free cohort of 65-year-olds was parameterized with real-world data (cancer and dementia incidence, mortality), assuming no effect of cancer on dementia (true IRR = 1.00). To introduce competing risk of death, cancer history increased mortality. To introduce selective survival, we included a factor (prevalence ranging from 10% to 50%) that reduced cancer mortality and dementia incidence (IRRs ranged from 0.30 to 0.90). We calculated IRRs for cancer history on dementia incidence in the simulated cohorts. RESULTS: Competing risk of death yielded unbiased cancer-dementia IRRs. With selective survival, bias was small (IRRs = 0.89 to 0.99), even under extreme scenarios. DISCUSSION: The bias induced by selective survival in simulations was too small to explain the observed inverse cancer-dementia link, suggesting other mechanisms drive this association.
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Viés , Simulação por Computador , Demência , Neoplasias , Idoso , Estudos de Coortes , Demência/epidemiologia , Demência/mortalidade , Feminino , Humanos , Incidência , Masculino , Neoplasias/epidemiologia , Neoplasias/mortalidade , Prevalência , Fatores de RiscoRESUMO
The thrombopoietin receptor agonist romiplostim is approved for second-line use in chronic immune thrombocytopenia (ITP), but its effects in patients with ITP for ≤1 year are not well characterized. This analysis of pooled data from 9 studies included patients with ITP for ≤1 year (n = 311) or >1 year (n = 726) who failed first-line treatments and received romiplostim, placebo or standard of care. In subgroup analysis by ITP duration, patient incidences for platelet response at ≥75% of measurements were higher for romiplostim [ITP ≤1 year: 74% (204/277); ITP >1 year: 71% (450/634)] than for placebo/standard of care [ITP ≤1 year: 18% (6/34); ITP >1 year: 9% (8/92)]. Of patients with ≥9 months on study, 16% with ITP ≤1 year and 6% with ITP >1 year discontinued romiplostim and maintained platelet counts ≥50 × 109 /l for ≥6 months without ITP treatment (treatment-free remission). Independent of ITP duration, rates of serious adverse events and bleeding were lower with romiplostim than placebo/standard of care and thrombotic events occurred at similar rates. In this analysis, romiplostim and placebo/standard of care had similar safety profiles and romiplostim increased platelet counts in patients with either ITP ≤1 year or ITP >1 year, with more treatment-free remission in those with ITP ≤1 year.
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Púrpura Trombocitopênica Idiopática , Receptores Fc , Proteínas Recombinantes de Fusão , Trombopoetina , Adulto , Idoso , Doença Crônica , Feminino , Hemorragia/sangue , Hemorragia/induzido quimicamente , Hemorragia/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade , Contagem de Plaquetas , Púrpura Trombocitopênica Idiopática/sangue , Púrpura Trombocitopênica Idiopática/diagnóstico , Púrpura Trombocitopênica Idiopática/tratamento farmacológico , Receptores Fc/administração & dosagem , Proteínas Recombinantes de Fusão/administração & dosagem , Proteínas Recombinantes de Fusão/efeitos adversos , Trombopoetina/administração & dosagem , Trombopoetina/efeitos adversos , Trombose/sangue , Trombose/induzido quimicamente , Trombose/diagnóstico , Fatores de TempoRESUMO
Objective- This study examined whether caveolae position CaV3.2 (T-type Ca2+ channel encoded by the α-3.2 subunit) sufficiently close to RyR (ryanodine receptors) for extracellular Ca2+ influx to trigger Ca2+ sparks and large-conductance Ca2+-activated K+ channel feedback. Approach and Results- Using smooth muscle cells from mouse mesenteric arteries, the proximity ligation assay confirmed that CaV3.2 reside within 40 nm of caveolin 1, a key caveolae protein. Methyl-ß-cyclodextrin, a cholesterol depleting agent that disrupts caveolae, suppressed CaV3.2 activity along with large-conductance Ca2+-activated K+-mediated spontaneous transient outward currents in cells from C57BL/6 but not CaV3.2-/- mice. Genetic deletion of caveolin 1, a perturbation that prevents caveolae formation, also impaired spontaneous transient outward current production but did so without impairing Ca2+ channel activity, including CaV3.2. These observations indicate a mistargeting of CaV3.2 in caveolin 1-/- mice, a view supported by a loss of Ni2+-sensitive Ca2+ spark generation and colocalization signal (CaV3.2-RyR) from the proximity ligation assay. Vasomotor and membrane potential measurements confirmed that cellular disruption of the CaV3.2-RyR axis functionally impaired the ability of large-conductance Ca2+-activated K+ to set tone in pressurized caveolin 1-/- arteries. Conclusions- Caveolae play a critical role in protein targeting and preserving the close structural relationship between CaV3.2 and RyR needed to drive negative feedback control in resistance arteries.
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Canais de Cálcio Tipo T/metabolismo , Sinalização do Cálcio , Cavéolas/metabolismo , Subunidades alfa do Canal de Potássio Ativado por Cálcio de Condutância Alta/metabolismo , Músculo Liso Vascular/metabolismo , Miócitos de Músculo Liso/metabolismo , Animais , Canais de Cálcio Tipo T/deficiência , Canais de Cálcio Tipo T/genética , Caveolina 1/genética , Caveolina 1/metabolismo , Retroalimentação Fisiológica , Masculino , Potenciais da Membrana , Artérias Mesentéricas/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Knockout , Canal de Liberação de Cálcio do Receptor de Rianodina/metabolismo , Vasoconstrição , VasodilataçãoRESUMO
Diabetic foot ulcer is one of the most frightened diabetic complications leading to amputation disability and early mortality. Diabetic wounds exhibit a complex networking of inflammatory cytokines, local proteases, and reactive oxygen and nitrogen species as a pathogenic polymicrobial biofilm, overall contributing to wound chronification and host homeostasis imbalance. Intralesional infiltration of epidermal growth factor (EGF) has emerged as a therapeutic alternative to diabetic wound healing, reaching responsive cells while avoiding the deleterious effect of proteases and the biofilm on the wound's surface. The present study shows that intralesional therapy with EGF is associated with the systemic attenuation of pro-inflammatory markers along with redox balance recovery. A total of 11 diabetic patients with neuropathic foot ulcers were studied before and 3 weeks after starting EGF treatment. Evaluations comprised plasma levels of pro-inflammatory, redox balance, and glycation markers. Pro-inflammatory markers such as erythrosedimentation rate, C-reactive protein, interleukin-6, soluble FAS, and macrophage inflammatory protein 1-alpha were significantly reduced by EGF therapy. Oxidative capacity, nitrite/nitrate ratio, and pentosidine were also reduced, while soluble receptor for advanced glycation end-products significantly increased. Overall, our results indicate that the local intralesional infiltration of EGF translates in systemic anti-inflammatory and antioxidant effects, as in attenuation of the glycation products' negative effects.
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Pé Diabético/tratamento farmacológico , Fator de Crescimento Epidérmico/uso terapêutico , Proteínas Recombinantes/uso terapêutico , Idoso , Arginina/análogos & derivados , Arginina/sangue , Biomarcadores/sangue , Sedimentação Sanguínea , Proteína C-Reativa/análise , Quimiocina CCL3/sangue , Citocinas/sangue , Feminino , Humanos , Injeções Intralesionais , Lisina/análogos & derivados , Lisina/sangue , Masculino , Pessoa de Meia-Idade , Nitratos/sangue , Nitritos/sangue , Receptor para Produtos Finais de Glicação Avançada/sangue , Cicatrização , Receptor fas/sangueRESUMO
Meta-analyses have reported a 2- to 3-fold increased risk of venous thrombosis (VT) in individuals with hyperhomocysteinemia. However, confounding factors were generally not considered. In contrast, randomized trials of homocysteine-lowering therapy and VT risk have been negative. We investigated whether hyperhomocysteinemia was associated with VT in the Multiple Environmental and Genetic Assessment of Risk Factors for Venous Thrombosis (MEGA) case-control study (1999-2004) from the Netherlands (1,689 cases and 1,726 controls), taking into account measured and unmeasured confounders. We compared patients with population controls to estimate odds ratios using unconditional logistic regression and adjusted for various potential confounders. We matched patients to their partners to additionally adjust for unmeasured confounders (e.g., lifestyle factors) using conditional logistic regression. We found that elevated homocysteine concentrations were not associated with an increased risk for VT when comparing patients with population controls, either as a continuous variable (odds ratio = 1.00, 95% confidence interval: 0.99, 1.01), in terms of 0.7-mg/L increase (odds ratio = 0.99, 95% confidence interval: 0.93, 1.05), or within different homocysteine categories. We obtained similar results when patients were compared with their partners. Stratification by sex, deep vein thrombosis, pulmonary embolism, provoked VT, and unprovoked VT also provided no evidence of an association. In conclusion, after extensive adjustments for confounding, hyperhomocysteinemia was not associated with an increased risk of venous thrombosis in this study.
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Hiper-Homocisteinemia/complicações , Trombose Venosa/etiologia , Adolescente , Adulto , Idoso , Estudos de Casos e Controles , Feminino , Humanos , Incidência , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Países Baixos/epidemiologia , Razão de Chances , Fatores de Risco , Trombose Venosa/epidemiologia , Adulto JovemRESUMO
Bradykinin-induced activation of the pulmonary endothelium triggers a rise in intracellular Ca2+ that activates nitric oxide (NO)-dependent vasorelaxation. Chronic hypoxia is commonly associated with increased pulmonary vascular tone, which can cause pulmonary hypertension in responsive individuals. In the present study, we tested the hypothesis that long-term high-altitude hypoxia (LTH) diminishes bradykinin-induced Ca2+ signals and inhibits endothelial nitric oxide synthase (eNOS), prostacyclin (PGI2), and large-conductance K+ (BKCa) channels in sheep, which are moderately responsive to LTH, resulting in decreased pulmonary arterial vasorelaxation. Pulmonary arteries were isolated from ewes kept near sea level (720 m) or at high altitude (3,801 m) for >100 days. Vessel force was measured with wire myography and endothelial intracellular Ca2+ with confocal microscopy. eNOS was inhibited with 100 µM NG-nitro-l-arginine methyl ester (l-NAME), PGI2 production was inhibited with 10 µM indomethacin that inhibits cyclooxygenase, and BKCa channels were blocked with 1 mM tetraethylammonium. Bradykinin-induced endothelial Ca2+ signals increased following LTH, but bradykinin relaxation decreased. Furthermore, some vessels contracted in response to bradykinin after LTH. l-NAME sensitivity decreased, suggesting that eNOS dysfunction played a role in uncoupling Ca2+ signals and bradykinin relaxation. The Ca2+ ionophore A-23187 (10 µM) elicited an enhanced Ca2+ response following LTH while relaxation was unchanged although l-NAME sensitivity increased. Additionally, BKCa function decreased during bradykinin relaxation following LTH. Western analysis showed that BKCa α-subunit expression was increased by LTH while that for the ß1 subunit was unchanged. Overall, these results suggest that those even moderately responsive to LTH can have impaired endothelial function.
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Altitude , Sinalização do Cálcio/efeitos dos fármacos , Hipóxia/metabolismo , Óxido Nítrico Sintase Tipo III/metabolismo , Artéria Pulmonar/efeitos dos fármacos , Animais , Bradicinina/farmacologia , Inibidores Enzimáticos/farmacologia , Epoprostenol/metabolismo , Canais de Potássio Ativados por Cálcio de Condutância Alta/metabolismo , Contração Muscular/efeitos dos fármacos , Relaxamento Muscular/efeitos dos fármacos , NG-Nitroarginina Metil Éster/farmacologia , Óxido Nítrico Sintase Tipo III/antagonistas & inibidores , OvinosRESUMO
Long-term hypoxia (LTH) has a profound effect on pulmonary arterial vasoconstriction in the fetus and adult. Dysregulation in Ca2+ signaling is important during the development of LTH-induced pulmonary hypertension. In the present study, we tested the hypothesis that L-type Ca2+ channels (CaL), which are voltage dependent and found in smooth, skeletal, and cardiac muscle, are important in the adaptation of pulmonary arterial contractions in postnatal maturation and in response to LTH. Pulmonary arteries were isolated from fetal or adult sheep maintained at low or high altitude (3,801 m) for >100 days. The effects were measured using an L-type Ca2+ channel opener FPL 64176 (FPL) in the presence or absence of an inhibitor, Nifedipine (NIF) on arterial contractions, intracellular Ca2+ oscillations, and ryanodine receptor-driven Ca2+ sparks. FPL induced pulmonary arterial contractions in all groups were sensitive to NIF. However, when compared with 125 mM K+, FPL contractions were greater in fetuses than in adults. FPL reduced Ca2+ oscillations in myocytes of adult but not fetal arteries, independently of altitude. The FPL effects on Ca2+ oscillations were reversed by NIF in myocytes of hypoxic but not normoxic adults. FPL failed to enhance Ca2+ spark frequency and had little impact on spatiotemporal firing characteristics. These data suggest that CaL-dependent contractions are largely uncoupled from intracellular Ca2+ oscillations and the development of Ca2+ sparks. This raises questions regarding the coupling of pulmonary arterial contractility to membrane depolarization, attendant CaL facilitation, and the related associations with the activation of Ca2+ oscillations and Ca2+ sparks.
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Doença da Altitude/metabolismo , Canais de Cálcio Tipo L/metabolismo , Sinalização do Cálcio , Cálcio/metabolismo , Artéria Pulmonar/metabolismo , Vasoconstrição , Doença da Altitude/fisiopatologia , Animais , Agonistas dos Canais de Cálcio/farmacologia , Bloqueadores dos Canais de Cálcio/farmacologia , Canais de Cálcio Tipo L/efeitos dos fármacos , Sinalização do Cálcio/efeitos dos fármacos , Modelos Animais de Doenças , Feminino , Coração Fetal/metabolismo , Coração Fetal/fisiopatologia , Idade Gestacional , Potenciais da Membrana , Miócitos Cardíacos/metabolismo , Gravidez , Artéria Pulmonar/efeitos dos fármacos , Artéria Pulmonar/embriologia , Artéria Pulmonar/fisiopatologia , Carneiro Doméstico , Fatores de Tempo , Vasoconstrição/efeitos dos fármacosRESUMO
KEY POINTS: Distinct Ca2+ channels work in a coordinated manner to grade Ca2+ spark/spontaneous transient outward currents (STOCs) in rat cerebral arteries. The relative contribution of each Ca2+ channel to Ca2+ spark/STOC production depends upon their biophysical properties and the resting membrane potential of smooth muscle. Na+ /Ca2+ exchanger, but not TRP channels, can also facilitate STOC production. ABSTRACT: Ca2+ sparks are generated in a voltage-dependent manner to initiate spontaneous transient outward currents (STOCs), events that moderate arterial constriction. In this study, we defined the mechanisms by which membrane depolarization increases Ca2+ sparks and subsequent STOC production. Using perforated patch clamp electrophysiology and rat cerebral arterial myocytes, we monitored STOCs in the presence and absence of agents that modulate Ca2+ entry. Beginning with CaV 3.2 channel inhibition, Ni2+ was shown to decrease STOC frequency in cells held at hyperpolarized (-40 mV) but not depolarized (-20 mV) voltages. In contrast, nifedipine, a CaV 1.2 inhibitor, markedly suppressed STOC frequency at -20 mV but not -40 mV. These findings aligned with the voltage-dependent profiles of L- and T-type Ca2+ channels. Furthermore, computational and experimental observations illustrated that Ca2+ spark production is intimately tied to the activity of both conductances. Intriguingly, this study observed residual STOC production at depolarized voltages that was independent of CaV 1.2 and CaV 3.2. This residual component was insensitive to TRPV4 channel modulation and was abolished by Na+ /Ca2+ exchanger blockade. In summary, our work highlights that the voltage-dependent triggering of Ca2+ sparks/STOCs is not tied to a single conductance but rather reflects an interplay among multiple Ca2+ permeable pores with distinct electrophysiological properties. This integrated orchestration enables smooth muscle to grade Ca2+ spark/STOC production and thus precisely tune negative electrical feedback.
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Sinalização do Cálcio , Artérias Cerebrais/metabolismo , Miócitos de Músculo Liso/metabolismo , Animais , Canais de Cálcio/metabolismo , Células Cultivadas , Artérias Cerebrais/citologia , Artérias Cerebrais/fisiologia , Feminino , Músculo Liso Vascular/citologia , Músculo Liso Vascular/metabolismo , Ratos , Ratos Sprague-Dawley , Trocador de Sódio e Cálcio/metabolismo , Canais de Cátion TRPV/metabolismoRESUMO
BACKGROUND: CIGB-247, a VSSP-adjuvanted VEGF-based vaccine, was evaluated in a phase I clinical trial in patients with advanced solid tumors (CENTAURO). Vaccination with the maximum dose of antigen showed an excellent safety profile, exhibited the highest immunogenicity and was the only one showing a reduction on platelet VEGF bioavailability. However, this antigen dose level did not achieve a complete seroconversion rate in vaccinated patients. These clinical results led us to the question whether a "reserve" of untapped immune response potential against VEGF could exist in cancer patients. To address this matter, CENTAURO-2 clinical trial was conducted where antigen and VSSP dose scale up were studied, and also incorporated the exploration of aluminum phosphate as adjuvant. These changes were made with the aim to increase immune response against VEGF. RESULTS: The present study reports the characterization of the humoral response elicited by CIGB-247 from the combining of different antigen doses and adjuvants. Cancer patients were immunologically monitored for approximately 1 year. Vaccination with different CIGB-247 formulations exhibited a very positive safety profile. Cancer patients developed IgM, IgG or IgA antibodies specific to VEGF. Elicited polyclonal antibodies had the ability to block the interaction between VEGF and its receptors, VEGFR1 and VEGFR2. The highest humoral response was detected in patients immunized with 800 µg of antigen + 200 µg of VSSP. Off-protocol long-term vaccination did not produce negative changes in humoral response. CONCLUSIONS: Vaccination with a human VEGF variant molecule as antigen in combination with VSSP or aluminum phosphate is immunogenic. The results of this study could contribute to the investigation of this vaccine therapy in an adequately powered efficacy trial. TRIAL REGISTRATION: Trial registration number: RPCEC00000155. Cuban Public Clinical Trial Registry. Date of registration: June 06, 2013. Available from: http://registroclinico.sld.cu/ .
Assuntos
Adjuvantes Imunológicos/administração & dosagem , Vacinas Anticâncer/imunologia , Imunidade Humoral/imunologia , Imunoterapia Ativa , Neoplasias/imunologia , Neoplasias/terapia , Fator A de Crescimento do Endotélio Vascular/imunologia , Animais , Antígenos de Neoplasias/administração & dosagem , Antígenos de Neoplasias/imunologia , Vacinas Anticâncer/administração & dosagem , Chlorocebus aethiops , Feminino , Humanos , Imunidade Humoral/efeitos dos fármacos , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Neoplasias/sangue , Coelhos , Receptores de Fatores de Crescimento do Endotélio Vascular/sangue , Receptores de Fatores de Crescimento do Endotélio Vascular/metabolismo , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/imunologia , Resultado do Tratamento , Fator A de Crescimento do Endotélio Vascular/metabolismoRESUMO
Microbiota are found in highly organized and complex entities, known as biofilms, the characteristics of which are fundamentally different from microbes in planktonic suspensions. Root canal infections are biofilm mediated. The complexity and variability of the root canal system, together with the multi-species nature of biofilms, make disinfection of this system extremely challenging. Microbial persistence appears to be the most important factor for failure of root canal treatment and this could further have an impact on pain and quality of life. Biofilm removal is accomplished by a chemo-mechanical process, using specific instruments and disinfecting chemicals in the form of irrigants and/or intracanal medicaments. Endodontic research has focused on the characterization of root canal biofilms and the clinical methods to disrupt the biofilms in addition to achieving microbial killing. In this narrative review, we discuss the role of microbial biofilms in endodontics and review the literature on the role of root canal disinfectants and disinfectant-activating methods on biofilm removal.
Assuntos
Biofilmes , Cavidade Pulpar/microbiologia , Animais , Endodontia/métodos , Humanos , Tratamento do Canal Radicular/métodosRESUMO
Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is a rare, clinically aggressive hematologic malignancy that most commonly manifests as cutaneous lesions with or without bone marrow involvement and leukemic dissemination. The demonstration of tumor cells with the characteristic immunophenotype with expression of CD56, generally CD4 and dendritic cell antigens (CD123, cyTCL-1, HLA-DR), in the absence of myeloid or lymphoid lineage markers is required for the diagnosis. Responses to chemotherapy are initially satisfactory, with frequent systemic and central nervous system relapses. We report a 24 year-old male with BPDCN, initially diagnosed and treated as non-Hodgkin CD4+ T-cell lymphoma, with initial complete remission who evolved with early central nervous system relapse. A second attempt of chemotherapy failed and the patient died two months later.
Assuntos
Neoplasias do Sistema Nervoso Central/secundário , Células Dendríticas/patologia , Neoplasias Hematológicas/patologia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Progressão da Doença , Evolução Fatal , Neoplasias Hematológicas/tratamento farmacológico , Humanos , Imunofenotipagem , Masculino , Indução de Remissão , Adulto JovemRESUMO
Bradykinin-induced activation of the pulmonary endothelium triggers nitric oxide production and other signals that cause vasorelaxation, including stimulation of large-conductance Ca(2+)-activated K(+) (BKCa) channels in myocytes that hyperpolarize the plasma membrane and decrease intracellular Ca(2+). Intrauterine chronic hypoxia (CH) may reduce vasorelaxation in the fetal-to-newborn transition and contribute to pulmonary hypertension of the newborn. Thus we examined the effects of maturation and CH on the role of BKCa channels during bradykinin-induced vasorelaxation by examining endothelial Ca(2+) signals, wire myography, and Western immunoblots on pulmonary arteries isolated from near-term fetal (â¼ 140 days gestation) and newborn, 10- to 20-day-old, sheep that lived in normoxia at 700 m or in CH at high altitude (3,801 m) for >100 days. CH enhanced bradykinin-induced relaxation of fetal vessels but decreased relaxation in newborns. Endothelial Ca(2+) responses decreased with maturation but increased with CH. Bradykinin-dependent relaxation was sensitive to 100 µM nitro-L-arginine methyl ester or 10 µM 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one, supporting roles for endothelial nitric oxide synthase and soluble guanylate cyclase activation. Indomethacin blocked relaxation in CH vessels, suggesting upregulation of PLA2 pathways. BKCa channel inhibition with 1 mM tetraethylammonium reduced bradykinin-induced vasorelaxation in the normoxic newborn and fetal CH vessels. Maturation reduced whole cell BKCa channel α1-subunit expression but increased ß1-subunit expression. These results suggest that CH amplifies the contribution of BKCa channels to bradykinin-induced vasorelaxation in fetal sheep but stunts further development of this vasodilatory pathway in newborns. This involves complex changes in multiple components of the bradykinin-signaling axes.
Assuntos
Bradicinina/metabolismo , Hipóxia/metabolismo , Vasodilatação/fisiologia , Animais , Arginina/análogos & derivados , Arginina/metabolismo , Endotélio Vascular/crescimento & desenvolvimento , Endotélio Vascular/metabolismo , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo III/metabolismo , Artéria Pulmonar/crescimento & desenvolvimento , Artéria Pulmonar/metabolismo , OvinosRESUMO
RATIONALE: T-type (CaV3.1/CaV3.2) Ca(2+) channels are expressed in rat cerebral arterial smooth muscle. Although present, their functional significance remains uncertain with findings pointing to a variety of roles. OBJECTIVE: This study tested whether CaV3.2 channels mediate a negative feedback response by triggering Ca(2+) sparks, discrete events that initiate arterial hyperpolarization by activating large-conductance Ca(2+)-activated K(+) channels. METHODS AND RESULTS: Micromolar Ni(2+), an agent that selectively blocks CaV3.2 but not CaV1.2/CaV3.1, was first shown to depolarize/constrict pressurized rat cerebral arteries; no effect was observed in CaV3.2(-/-) arteries. Structural analysis using 3-dimensional tomography, immunolabeling, and a proximity ligation assay next revealed the existence of microdomains in cerebral arterial smooth muscle which comprised sarcoplasmic reticulum and caveolae. Within these discrete structures, CaV3.2 and ryanodine receptor resided in close apposition to one another. Computational modeling revealed that Ca(2+) influx through CaV3.2 could repetitively activate ryanodine receptor, inducing discrete Ca(2+)-induced Ca(2+) release events in a voltage-dependent manner. In keeping with theoretical observations, rapid Ca(2+) imaging and perforated patch clamp electrophysiology demonstrated that Ni(2+) suppressed Ca(2+) sparks and consequently spontaneous transient outward K(+) currents, large-conductance Ca(2+)-activated K(+) channel mediated events. Additional functional work on pressurized arteries noted that paxilline, a large-conductance Ca(2+)-activated K(+) channel inhibitor, elicited arterial constriction equivalent, and not additive, to Ni(2+). Key experiments on human cerebral arteries indicate that CaV3.2 is present and drives a comparable response to moderate constriction. CONCLUSIONS: These findings indicate for the first time that CaV3.2 channels localize to discrete microdomains and drive ryanodine receptor-mediated Ca(2+) sparks, enabling large-conductance Ca(2+)-activated K(+) channel activation, hyperpolarization, and attenuation of cerebral arterial constriction.