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1.
Semin Thromb Hemost ; 48(6): 680-689, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36223771

RESUMO

Activated protein C (APC) resistance (APCR) is considered a risk factor of venous thromboembolism (VTE). The most common genetic disorder conferring APCR is a factor (F) V Leiden mutation, but many other factors are also implicated, such as other F5 mutations (e.g., FV Hong-Kong and FV Cambridge), protein S deficiency, elevated factor VIII, exogenous hormone use, pregnancy and postpartum, depending on how APCR is defined. Considering the large population affected, the detection of this phenotype is crucial. Two types of tests are currently available: clotting time-based assays (with several versions) and thrombin generation-based assays with the endogenous thrombin potential (ETP)-based assay. The purpose of this review is therefore to discuss the performances of these tests and the cases in which it would be appropriate to use one over the other. Initially, as APCR was thought to be solely related to the FV Leiden mutation, the objective was to obtain a 100% specific assay. Clotting-time based assays were thus specifically designed to detect this inherited condition. Later on, an APCR condition without a FV Leiden mutation was identified and highlighted as an independent risk factor of VTE. Therefore, the development of a less specific assay was needed and a global coagulation test was proposed, known as the ETP-based APCR assay. In light of the above, these tests should not be used for the same purpose. Clotting time-based assays should only be recommended as a screening test for the detection of FV mutations prior to confirmation by genetic testing. On the other hand, the ETP-based APC resistance assay, in addition to being able to detect any type of APCR, could be proposed as a global screening test as it assesses the entire coagulation process.


Assuntos
Resistência à Proteína C Ativada , Tromboembolia Venosa , Resistência à Proteína C Ativada/diagnóstico , Resistência à Proteína C Ativada/genética , Fator V/genética , Fator VIII , Feminino , Hormônios , Humanos , Fenótipo , Gravidez , Proteína C/genética , Trombina/genética , Trombofilia , Tromboembolia Venosa/diagnóstico , Tromboembolia Venosa/genética
2.
FASEB J ; 36(11): e22583, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36197017

RESUMO

Water homeostasis is tightly regulated by the kidneys via the process of urine concentration. During reduced water intake, the antidiuretic hormone arginine vasopressin (AVP) binds to the vasopressin receptor type II (V2R) in the kidney to enhance countercurrent multiplication and medullary osmolality, and increase water reabsorption via aquaporin-2 (AQP2) water channels. The importance of this AVP, V2R, and AQP2 axis is highlighted by low urine osmolality and polyuria in people with various water balance disorders, including nephrogenic diabetes insipidus (NDI). ELF5 and nuclear factor of activated T cells 5 (NFAT5) are two transcription factors proposed to regulate Aqp2 expression, but their role is poorly defined. Here we generated two novel mouse lines with principal cell (PC)-specific deletion of ELF5 or NFAT5 and phenotyped them in respect to renal water handling. ELF5-deficient mice (ELF5PC-KO ) had a very mild phenotype, with no clear differences in AQP2 abundance, and mild differences in renal water handling and maximal urinary concentrating capacity. In contrast, NFAT5 (NFAT5PC-KO ) mice had significantly higher water intake and their 24 h urine volume was almost 10-fold greater than controls. After challenging with dDAVP or 8 h water restriction, NFAT5PC-KO mice were unable to concentrate their urine, demonstrating that they suffer from NDI. The abundance of AQP2, other AQPs, and the urea transporter UT-A1 were greatly decreased in NFAT5PC-KO mice. In conclusion, NFAT5 is a major regulator of not only Aqp2 gene transcription, but also other genes important for water homeostasis and its absence leads to the development of NDI.


Assuntos
Diabetes Insípido Nefrogênico , Diabetes Mellitus , Túbulos Renais Coletores , Fatores de Transcrição/metabolismo , Animais , Aquaporina 2/genética , Aquaporina 2/metabolismo , Arginina Vasopressina/metabolismo , Desamino Arginina Vasopressina/metabolismo , Diabetes Insípido Nefrogênico/genética , Diabetes Insípido Nefrogênico/metabolismo , Diabetes Mellitus/metabolismo , Fator V/metabolismo , Túbulos Renais Coletores/metabolismo , Camundongos , Receptores de Vasopressinas/genética , Receptores de Vasopressinas/metabolismo , Linfócitos T/metabolismo , Fatores de Transcrição/genética , Vasopressinas/metabolismo , Água/metabolismo
3.
J Biol Chem ; 298(11): 102558, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36183835

RESUMO

Activated protein C (APC) is an important anticoagulant protein that regulates thrombin generation through inactivation of factor V (FV) and activated factor V (FVa). The rate of APC inactivation of FV is slower compared to FVa, although proteolysis occurs at the same sites (Arg306, Arg506, and Arg679). The molecular basis for FV resistance to APC is unknown. Further, there is no information about how FV-short, a physiologically relevant isoform of FV with a shortened B-domain, is regulated by APC. Here, we identify the molecular determinants which differentially regulate APC recognition of FV versus FVa and uncover how FV-short can be protected from this anticoagulant pathway. Using recombinant FV derivatives and B-domain fragments, we show that the conserved basic region (BR; 963-1008) within the central portion of the B-domain plays a major role in limiting APC cleavage at Arg506. Derivatives of FV lacking the BR, including FV-short, were subject to rapid cleavage at Arg506 and were inactivated like FVa. The addition of a FV-BR fragment reversed this effect and delayed APC inactivation. We also found that anticoagulant glycoprotein TFPIα, which has a C-terminal BR homologous to FV-BR, protects FV-short from APC inactivation by delaying cleavage at Arg506. We conclude that the FV-BR plays a major role in protecting FV from APC inactivation. Using a similar mechanistic strategy, TFPIα also shields FV-short from APC. These findings clarify the resistance of FV to APC, advance our understanding of FV/FVa regulation, and establish a mechanistic framework for manipulating this reaction to alter coagulation.


Assuntos
Fator V , Proteína C , Fator V/genética , Fator V/metabolismo , Proteína C/genética , Proteína C/metabolismo , Anticoagulantes , Peptídeo Hidrolases , Fator Va/genética , Fator Va/metabolismo , Trombina/metabolismo
4.
Am J Case Rep ; 23: e937312, 2022 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-36116005

RESUMO

BACKGROUND Combined factor V and factor VIII deficiency (F5F8D) is a rare bleeding disorder with an incidence of 1: 1 000 000. The identified mutations were observed in LMAN1 and MCFD2 genes. This case report presents the cases of 3 Saudi siblings with the genetic mutation of LMAN1 causing F5F8D, and highlights the challenges in diagnosis and treatment. CASE REPORT Patient X, a 7-year-old boy, was misdiagnosed with hemophilia A after a history of prolonged circumcision bleeding and epistaxis. He was referred to our clinic for pre-operative assessment. Blood workup showed prolonged PT and aPTT, which were normalized by mixing studies. Since his previous diagnosis could not explain a prolonged PT, further investigations were performed, revealing low levels of FVIII and FV. Genetic testing confirmed a c.822G>A homozygous LMAN1 mutation. The other 2 siblings (patient Y and Z), who were 5- and 12-year-old, respectively, girls, were also assessed. They both had a history of epistaxis. The younger sibling also had an episode of bleeding after tooth extraction, and physical examination of this patient revealed a bruise over her left thigh. The older sibling had menorrhagia. Blood workup of both revealed prolonged PT and aPTT, with complete correction by mixing study, and low levels of FV and FVIII. The patients' backgrounds and lab results were highly suggestive of F5F8D. CONCLUSIONS This case report describes an extremely rare bleeding disorder. More attention should be directed toward this disease, and a careful evaluation of suspicious cases should be performed to better diagnose and manage these patients.


Assuntos
Fator V , Irmãos , Criança , Pré-Escolar , Epistaxe/etiologia , Fator V/genética , Deficiência do Fator V , Feminino , Hemofilia A , Humanos , Masculino , Lectinas de Ligação a Manose/genética , Proteínas de Membrana/genética , Mutação , Arábia Saudita , Proteínas de Transporte Vesicular/genética
5.
Int J Mol Sci ; 23(18)2022 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-36142408

RESUMO

The epithelial-mesenchymal transition (EMT) is a differentiation process associated with fibrogenesis in diabetic nephropathy (DN). Lysophosphatidic acid (LPA) is a small, naturally occurring glycerophospholipid implicated in the pathogenesis of DN. In this study, we investigated the role of LPA/LPAR1 signaling in the EMT of tubular cells as well as the underlying mechanisms. We observed a decrease in E-cadherin and an increase in vimentin expression levels in the kidney tubules of diabetic db/db mice, and treatment with ki16425 (LPAR1/3 inhibitor) inhibited the expression of these EMT markers. Ki16425 treatment also decreased the expression levels of the fibrotic factors fibronectin and alpha-smooth muscle actin (α-SMA) in db/db mice. Similarly, we found that LPA decreased E-cadherin expression and increased vimentin expression in HK-2 cells, which was reversed by treatment with ki16425 or AM095 (LPAR1 inhibitor). In addition, the expression levels of fibronectin and α-SMA were increased by LPA, and this effect was reversed by treatment with ki16425 and AM095 or by LPAR1 knockdown. Moreover, LPA induced the expression of the transcription factor, Krüppel-like factor 5 (KLF5), which was decreased by AM095 treatment or LPAR1 knockdown. The expression levels of EMT markers and fibrotic factors induced by LPA were decreased upon KLF5 knockdown in HK-2 cells. Inhibition of the extracellular signal-regulated kinase (ERK), c-Jun N-terminal kinase (JNK), and serine-threonine kinase (AKT) pathways decreased LPA-induced expression of KLF5 and EMT markers. In conclusion, these data suggest that LPA contributes to the pathogenesis of diabetic nephropathy by inducing EMT and renal tubular fibrosis via regulation of KLF5 through the LPAR1.


Assuntos
Nefropatias Diabéticas , Actinas/metabolismo , Animais , Caderinas/metabolismo , Nefropatias Diabéticas/metabolismo , Células Epiteliais/metabolismo , Transição Epitelial-Mesenquimal , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Fator V , Fibronectinas/metabolismo , Fibrose , Glicerofosfolipídeos/metabolismo , Isoxazóis , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Túbulos Renais/metabolismo , Fatores de Transcrição Kruppel-Like/genética , Fatores de Transcrição Kruppel-Like/metabolismo , Lisofosfolipídeos , Camundongos , Propionatos , Proteínas Serina-Treonina Quinases , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Fatores de Transcrição/metabolismo , Vimentina/metabolismo
6.
J Clin Lab Anal ; 36(11): e24705, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36125894

RESUMO

BACKGROUND: Congenital coagulation factor V (FV) deficiency is a very rare hemorrhagic disease with an incidence of approximately one in a million. The common clinical manifestations of FV deficiency include ecchymosis and mucosal bleeding. Life-threatening intracranial bleeding is rare. It has been reported in several cases. However, the molecular basis has been established in only a few cases. METHODS: We reported a 2-month-old girl with congenital FV deficiency and intracranial hemorrhage. Coagulation screening combined with clinical manifestations was performed to diagnose congenital FV deficiency. Genetic testing was performed to identify the pathogenic genes. A literature review was included to emphasize the clinical manifestation, diagnosis, and treatment for congenital FV deficiency with intracranial bleeding. RESULTS: The coagulation tests revealed a significantly prolonged prothrombin time (PT) of 51 s and an activated partial thromboplastin time (APTT) of 73.7 s. The patient had a plasma FV activity of 0.9%. Genetic testing showed compound heterozygous mutations of the patient's FV gene. A literature review showed that patients with homozygous or compound heterozygous variants of the FV gene were often associated with a severe bleeding phenotype. CONCLUSION: Our study provides a direction for the rapid and accurate diagnosis and treatment for FV deficiency to avoid life-threatening bleeding. Infants with spontaneous cranial hematoma and intracranial hemorrhage should be investigated for underlying hemostatic defects. Congenital coagulation factor deficiency should be considered. Once congenital FV deficiency is diagnosed, fresh frozen plasma (FFP) should be given on a regular basis. Liver transplantation may be performed in severe cases.


Assuntos
Resistência à Proteína C Ativada , Deficiência do Fator V , Humanos , Fator V/genética , Deficiência do Fator V/complicações , Deficiência do Fator V/genética , Deficiência do Fator V/congênito , Hemorragias Intracranianas/genética
7.
J Feline Med Surg ; 24(10): e353-e359, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36047983

RESUMO

OBJECTIVES: The most common use of plasma transfusion is for haemostatic purposes, but coagulation factor activities in stored feline plasma are unknown. The concentration and stability of coagulation factors I (fibrinogen), II, V, VII, VIII, IX, X, XI and XII in feline fresh frozen plasma (fFFP) stored for 1 year were studied. METHODS: Fifty-five units of fFFP were produced from 55 fresh whole-blood donations obtained from indoor healthy blood donor cats. Twenty-one units were stored for <2 weeks (T0) and 34 were stored for 1 year (T1). After the completion of storage, specific coagulation factor activities for factors II, V, VII, VIII, IX, X, XI and XII were tested using modified one-stage activated partial thromboplastin or prothrombin time assays. Fibrinogen was determined using the Clauss method. RESULTS: Significantly decreased activities were observed for factors II (T0: 101.94% ± 19.06%; T1: 73.23% ± 39.06% [P = 0.001]), VII (T0: 102.78% ± 24.69%; T1: 60.08% ± 38.17% [P <0.001]), VIII (T0: 77.52% ± 30.39%; T1: 50.32% ± 23.8% [P = 0.001]), XI (T0: 88.76% ± 22.73%; T1: 66.28% ± 22.2% [P = 0.001]) and XII (T0: 89.50% ± 21.85%; T1: 55.46% ± 23.18% [P <0.001]) when comparing units at time 0 and after 1 year of storage. No significant difference was observed for factors IX (T0: 84.86% ± 29.35%; T1: 71.37% ± 22.23% [P = 0.064]) and X (T0: 96.24% ± 25.1%; T1: 83.91% ± 49.54% [P = 0.236]). Unexpectedly, a significant increase was observed for factor V (T0: 71.94% ± 24.14%; T1: 97.89% ± 62.33%; P = 0.046). Fibrinogen was 2.76 ± 1.09 g/l at T1. Factors VIII, XII and VII had the lowest mean activities after 1 year. CONCLUSIONS AND RELEVANCE: Although a decrease in most coagulation factors activities was noted with storage, 1-year-old fFFP was haemostatically active in vitro. The most suitable factors for quality control assessment of fFFP are factors VII and VIII. Approximately 13-20 ml/kg of fFFP is required to administer a minimum of 10 IU/kg coagulation factor activity.


Assuntos
Hemostáticos , Plasma , Animais , Transfusão de Componentes Sanguíneos/veterinária , Gatos , Fator V , Fibrinogênio , Tromboplastina
8.
Expert Rev Hematol ; 15(10): 927-931, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35980129

RESUMO

INTRODUCTION: The utilization of artificial intelligence (AI) in hemophilia is still in its early phases. AREAS COVERED: In this paper a review of the available information on AI in hemophilia has been performed, to better understand the relationship between hemophilia and AI. Regarding the physical elements of AI (robotics), robotic-assisted total knee arthroplasty and laparoscopic prostatectomy have been successfully performed in hemophilic patients. Concerning the virtual elements of AI, machine learning (ML) in hemophilia has been used with encouraging results for the following: prediction of disease severity, recognition of factor V as an essential modifier of thrombin generation in mild to moderate hemophilia A, development hemophilia-focused user-centered app, gene therapy, estimation of the risk of myocardial infarction, and identification of CRISPR/Cas9 nuclease off-target for the treatment of hemophilia. AI is an emerging reality that can produce a paradigm shift in hemophilia. EXPERT OPINION: Various AI systems can facilitate clinical care for professionals, improving the diagnosis and treatment of hemophilia. However, AI systems still have many limitations and raise operational and ethical issues. AI systems should be integrated prudently and reasonably within the practitioner's workflow.


Assuntos
Hemofilia A , Robótica , Humanos , Inteligência Artificial , Hemofilia A/diagnóstico , Hemofilia A/terapia , Fator V , Trombina
9.
EMBO J ; 41(19): e110988, 2022 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-35942625

RESUMO

One of the hallmarks of plant senescence is the global transcriptional reprogramming coordinated by a plethora of transcription factors (TFs). However, mechanisms underlying the interactions between different TFs in modulating senescence remain obscure. Previously, we discovered that plant ABS3 subfamily MATE transporter genes regulate senescence and senescence-associated transcriptional changes. In a genetic screen for mutants suppressing the accelerated senescence phenotype of the gain-of-function mutant abs3-1D, AUXIN RESPONSE FACTOR 2 (ARF2) and PHYTOCHROME-INTERACTING FACTOR 5 (PIF5) were identified as key TFs responsible for transcriptional regulation in the ABS3-mediated senescence pathway. ARF2 and PIF5 (as well as PIF4) interact directly and function interdependently to promote senescence, and they share common target genes such as key senescence promoting genes ORESARA 1 (ORE1) and STAY-GREEN 1 (SGR1) in the ABS3-mediated senescence pathway. In addition, we discovered reciprocal regulation between ABS3-subfamily MATEs and the ARF2 and PIF5/4 TFs. Taken together, our findings reveal a regulatory paradigm in which the ARF2-PIF5/4 functional module facilitates the transcriptional reprogramming in the ABS3-mediated senescence pathway.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Fitocromo , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Fator V/genética , Fator V/metabolismo , Regulação da Expressão Gênica de Plantas , Ácidos Indolacéticos/metabolismo , Fitocromo/genética , Senescência Vegetal , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
10.
Sci Total Environ ; 849: 157791, 2022 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-35940262

RESUMO

An aquifer storage transfer and recovery (ASTR) system was studied in which tile drainage water (TDW) was injected with relatively high NO3 (about 14 mg/L) concentrations originating from fertilizers. Here we present the evolution of denitrification kinetics at 6 different depths in the aquifer before, and during ASTR operation. First-order denitrification rate constants increased over time before and during the first days of ASTR operation, likely due to microbial adaptation of the native bacterial community and/or bioaugmentation of the aquifer by denitrifying bacteria present in injected TDW. Push-pull tests were performed in the native aquifer before ASTR operation. Obtained first-order denitrification rate constants were negligible (0.00-0.03 d-1) at the start, but increased to 0.17-0.83 d-1 after a lag-phase of about 6 days. During the first days of ASTR operation in autumn 2019, the arrival of injected TDW was studied at 2.5 m distance from the injection well. First-order denitrification rate constants increased again over time (maximum >1 d-1). Three storage periods without injection were monitored in winter 2019, fall 2020, and spring 2021 during ASTR operation. First-order rate constants ranged between 0.12 and 0.61 d-1. Denitrification coupled to pyrite oxidation occurred at all depths, but other oxidation processes were indicated as well. NO3 concentration trends resembled Monod kinetics but were fitted also to a first-order decay rate model to facilitate comparison. Rate constants during the storage periods were substantially lower than during injection, probably due to a reduction in the exchange rate between aquifer solid phases and injected water during the stagnant conditions. Denitrification rate constants deviated maximally a factor 5 over time and depth for all in-situ measurement approaches after the lag-phase. The combination of these in-situ approaches enabled to obtain more detailed insights in the evolution of denitrification kinetics during AS(T)R.


Assuntos
Água Subterrânea , Poluentes Químicos da Água , Desnitrificação , Fator V , Fertilizantes , Água Subterrânea/microbiologia , Cinética , Nitratos/análise , Água , Poluentes Químicos da Água/análise
11.
Chemosphere ; 307(Pt 2): 135815, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35921885

RESUMO

Electrospray ionization (ESI) is the most common technique in liquid chromatography coupled to tandem mass spectrometry (LC-MS-MS) allowing for sensitive detection of polar compounds with online water concentration. The technique is popular in groundwater monitoring programs and has permitted great progress in the detection and quantification of polar pesticide transformation products (TP) in recent years. However, ESI is also known to be prone to matrix effects. The common solution to this potential bias is the use of labelled internal standards. Unfortunately, these are not available for all target compounds, which leads to the linkage of target compounds to non-homologue internal standards with unknown consequences for quantification in variable geochemical settings. We investigated these matrix effects for polar TP with a molecular mass range of 225-350 Da and logDpH7 between -0.27 and -1.7 as well as for parent compounds with logDpH3 between 0.84 and 3.22. The acquired internal standards were tested on a gradient of DOC, anions, conductivity and inorganic carbon with a set of ten carefully chosen groundwater samples. Internal standards that were measured in positive ionization mode proved to be insensitive to geochemical variations while those that were measured in negative ionization mode showed reduced response with increasing anion concentration. All pairs of internal standards and target analytes were investigated for deviating matrix effects using standard addition experiments. Positive ionization compounds and target compounds with deuterated homologues showed little deviation while non-homologue pairs in negative mode proved to be strongly biased. Although bias was up to factor five for some compounds it was remarkably stable over the entire gradient studied, suggesting an identical suppression mode at varying matrix levels for different compounds. We advocate the conduct of standard addition experiments if homologue internal standards are not available.


Assuntos
Água Subterrânea , Praguicidas , Carbono , Cromatografia Líquida de Alta Pressão/métodos , Fator V , Praguicidas/análise , Espectrometria de Massas por Ionização por Electrospray/métodos , Água/análise
13.
Int J Mol Sci ; 23(15)2022 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-35955419

RESUMO

The vascular endothelium has several important functions, including hemostasis. The homeostasis of hemostasis is based on a fine balance between procoagulant and anticoagulant proteins and between fibrinolytic and antifibrinolytic ones. Coagulopathies are characterized by a mutation-induced alteration of the function of certain coagulation factors or by a disturbed balance between the mechanisms responsible for regulating coagulation. Homeostatic therapies consist in replacement and nonreplacement treatments or in the administration of antifibrinolytic agents. Rebalancing products reestablish hemostasis by inhibiting natural anticoagulant pathways. These agents include monoclonal antibodies, such as concizumab and marstacimab, which target the tissue factor pathway inhibitor; interfering RNA therapies, such as fitusiran, which targets antithrombin III; and protease inhibitors, such as serpinPC, which targets active protein C. In cases of thrombophilia (deficiency of protein C, protein S, or factor V Leiden), treatment may consist in direct oral anticoagulants, replacement therapy (plasma or recombinant ADAMTS13) in cases of a congenital deficiency of ADAMTS13, or immunomodulators (prednisone) if the thrombophilia is autoimmune. Monoclonal-antibody-based anti-vWF immunotherapy (caplacizumab) is used in the context of severe thrombophilia, regardless of the cause of the disorder. In cases of disseminated intravascular coagulation, the treatment of choice consists in administration of antifibrinolytics, all-trans-retinoic acid, and recombinant soluble human thrombomodulin.


Assuntos
Fator V/metabolismo , Trombofilia , Fator de von Willebrand , Anticoagulantes , Endotélio Vascular/metabolismo , Fator VIII/genética , Fator VIII/uso terapêutico , Homeostase , Humanos , Proteína C/uso terapêutico , Trombofilia/genética , Fator de von Willebrand/metabolismo
14.
J Integr Plant Biol ; 64(11): 2097-2110, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36029156

RESUMO

Light signaling precisely controls photomorphogenic development in plants. PHYTOCHROME INTERACTING FACTOR 4 and 5 (PIF4 and PIF5) play critical roles in the regulation of this developmental process. In this study, we report CONSTITUTIVELY PHOTOMORPHOGENIC 1 SUPPRESSOR 6 (CSU6) functions as a key regulator of light signaling. Loss of CSU6 function largely rescues the cop1-6 constitutively photomorphogenic phenotype. CSU6 promotes hypocotyl growth in the dark, but inhibits hypocotyl elongation in the light. CSU6 not only associates with the promoter regions of PIF4 and PIF5 to inhibit their expression in the morning, but also directly interacts with both PIF4 and PIF5 to repress their transcriptional activation activity. CSU6 negatively controls a group of PIF4- and PIF5-regulated gene expressions. Mutations in PIF4 and/or PIF5 are epistatic to the loss of CSU6, suggesting that CSU6 acts upstream of PIF4 and PIF5. Taken together, CSU6 promotes light-inhibited hypocotyl elongation by negatively regulating PIF4 and PIF5 transcription and biochemical activity.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Fitocromo , Hipocótilo/metabolismo , Fitocromo/genética , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Complexo I de Proteína do Envoltório/genética , Complexo I de Proteína do Envoltório/metabolismo , Fator V/genética , Fator V/metabolismo , Regulação da Expressão Gênica de Plantas , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo
15.
Medicina (Kaunas) ; 58(8)2022 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-36013544

RESUMO

The aim of this review is to highlight all the factors that associate venous thromboembolism (VTE) with aging. Elderly people are characterized by a higher incidence of thrombosis taking into account the co-existing comorbidities, complications and fatality that arise. Based on the Virchow triad, pathophysiological aspects of venous stasis, endothelium injury and hypercoagulability in elderly people (≥65 years) are described in detail. More precisely, venous wall structure, nitric oxide (NO) and endothelin-1 expression are impaired in this age group. Furthermore, an increase in high-molecular-weight kininogen (HMWK), prekallikrein, factors V, VII, VIII, IX and XI, clot lysis time (CLT) and von Willebrand factor (vWF) is observed. Age-dependent platelet dysfunction and changes in anticoagulant factors are also illustrated. A "low-grade inflammation stage" is delineated as a possible risk factor for thrombosis in the elderly. Consequently, clinical implications for frail elderly people related to diagnosis, treatment, bleeding danger and VTE recurrence emerge. We conclude that aging is an acquired thrombotic factor closely related to pathophysiological changes.


Assuntos
Tromboembolia Venosa , Idoso , Envelhecimento , Fator V , Humanos , Fatores de Risco , Tromboembolia Venosa/epidemiologia , Fator de von Willebrand/metabolismo
16.
Front Immunol ; 13: 928593, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35967345

RESUMO

The microRNAs miR-144/451 are highly conserved miRNA that is strongly induced during erythropoiesis. Despite the biological functions of miR-144/451 have been extensively studied in erythropoiesis and tumorigenesis, few studies have been conducted in immune responses. In this study, we showed that miR-144/451-/- DCs exhibit increased activation. Mechanistically, the miR-144 directly targets the 3`-UTR of IRF5 and represses the expression of IRF5 in DCs. Ectopic expression of miR-144/451 by lentiviruses downregulates the levels of IRF5 and suppresses DCs function. In addition, knockdown of IRF5 by shRNA significantly inhibits activities of the miR-144/451-/- DCs. Expression of miR144/451 was decreased in DCs from both patients with IBD and mice with DSS-colitis compared with controls. Human PBMC derived DCs were downregulated expression of miR144/451 after LPS stimulation. In the DSS-induced colitis mice model, we showed that ablation of the miR-144/451 gene causes severe colitis, and their DCs from both periphery and MLN expressed higher co-stimulatory molecules and pro-inflammatory cytokines than wild-type mice. In addition, DCs isolated from miR-144/451-/- mice transfusion exacerbates mice colitis. In the bone marrow transplanted chimeric mice model, we show that miR-144/451-/- bone marrow transplantation deteriorated DSS-induced colitis. At last, we treat the mice with miR-144/451 delivered by chitosan nanoparticles revealing protective effects in DSS-induced colitis mice. Thus, our results reveal a novel miR144/451-IRF5 pathway in DCs that protects experimental colitis. The manipulation of miR-144/451 expression and DCs activation in IBD patients may be a novel therapeutic approach for the treatment of inflammatory diseases.


Assuntos
Colite , Células Dendríticas , Doenças Inflamatórias Intestinais , Fatores Reguladores de Interferon , MicroRNAs , Animais , Colite/induzido quimicamente , Colite/genética , Colite/imunologia , Células Dendríticas/imunologia , Modelos Animais de Doenças , Fator V , Humanos , Doenças Inflamatórias Intestinais/genética , Doenças Inflamatórias Intestinais/imunologia , Fatores Reguladores de Interferon/genética , Fatores Reguladores de Interferon/imunologia , Interferons/imunologia , Leucócitos Mononucleares/imunologia , Camundongos , MicroRNAs/genética , MicroRNAs/imunologia
17.
Sci Total Environ ; 848: 157579, 2022 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-35901896

RESUMO

The ambient air pollution by particulate matter (PM) has strong negative effects on human health. Recent studies have found correlations between pollution and mortality due to Covid-19. We present here an analysis of such correlation for 32 locations in 6 countries of the Western Europe (France, Germany, Italy, Netherlands, Spain, United Kingdom), for the 2020-2022 period. The data are weekly averaged, and the mortality values were normalized considering the population of the locations. A correlation is qualitatively found for the time-series of PM2.5 pollution and Covid-19 mortality. The higher mortality values occurred during the pollutions peaks, as presented for the city of Paris (France) and the Lombardy regions (Italia), one of the more polluted locations in Western Europe. An almost linear trend with a factor 5.5 ± 1.0 increase in mortality when the pollution increases to ~45 µg.m-3 is found when considering all data. This leads to an increase of 10.5 ± 2.5 % of mortality per 1 µg.m-3. More precisely, the trend depends on the period of the analysis and decreases with time (first spread of the pandemic in Spring 2020, mid-2020 - mid 2021 period where the pandemic was better managed, and vaccinal race after mid-2021). Finally, although the initial conditions could differ from one country to another, the relative trend of increase was similar for the countries here considered. Such results can have some implication on the management of the Covid-19 pandemic and other cardiopulmonary diseases during PM pollution events. They also show the importance of reducing the PM pollution in the major cities.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , COVID-19 , Poluentes Atmosféricos/análise , Poluição do Ar/análise , Europa (Continente)/epidemiologia , Fator V , Humanos , Pandemias , Material Particulado/análise
18.
Int J Lab Hematol ; 44(5): 952-958, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35815444

RESUMO

INTRODUCTION: The aim of our study was to establish reference ranges for neonatal coagulation and fibrinolysis parameters and to investigate their relationship with gestational age (GA) and birth weight (BW). METHODS: A single-centre prospective study was conducted in all healthy neonates born in our hospital during the study period, excluding those with maternal or neonatal disorders and diseases that affect haemostasis. The following parameters were measured: fibrinogen, prothrombin time (PT), international normalized ratio (INR), activated partial thromboplastin time (aPTT) as well as factors II, V, VII, VIII, IX, X, XI and XII, von Willebrand (vWF), protein C, free protein S, antithrombin (AT), activated protein C resistance (APCr), tissue plasminogen activator (tPA) and plasminogen activator inhibitor-1 (PAI-1). RESULTS: Study population consisted of 327 neonates. Fibrinogen, AT III, proteins C and S, PAI-1, vWF and factors II, V, VIII, IX, XI and XII were positively correlated, while PT, aPPT, INR, APCr and tPA were negatively correlated with GA and BW. Proteins C and S, factors II, VIII, IX, XI and vWF, as well AT III and PAI-1 had a significant positive linear correlation with GA, while aPTT had a significant negative one. Fibrinogen, and factors V, VII and XII had a significant positive linear correlation with BW, while factor VIII, tPA, as well PT and INR had a significant negative one. CONCLUSION: Fibrinogen, AT III, proteins C and S, PAI-1, vWF and factors II, V, VIII, IX, XI and XII increase with GA and BW.


Assuntos
Hemostáticos , Inibidor 1 de Ativador de Plasminogênio , Peso ao Nascer , Fatores de Coagulação Sanguínea/metabolismo , Fator V , Fibrinogênio , Idade Gestacional , Hemostasia , Humanos , Recém-Nascido , Estudos Prospectivos , Proteína C/metabolismo , Protrombina , Ativador de Plasminogênio Tecidual , Fator de von Willebrand
19.
Nat Commun ; 13(1): 4071, 2022 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-35831302

RESUMO

Leishmania are unicellular parasites that cause human and animal diseases. Like other kinetoplastids, they possess large transcriptional start regions (TSRs) which are defined by histone variants and histone lysine acetylation. Cellular interpretation of these chromatin marks is not well understood. Eight bromodomain factors, the reader modules for acetyl-lysine, are found across Leishmania genomes. Using L. mexicana, Cas9-driven gene deletions indicate that BDF1-5 are essential for promastigotes. Dimerisable, split Cre recombinase (DiCre)-inducible gene deletion of BDF5 show it is essential for both promastigotes and murine infection. ChIP-seq identifies BDF5 as enriched at TSRs. XL-BioID proximity proteomics shows the BDF5 landscape is enriched for BDFs, HAT2, proteins involved in transcriptional activity, and RNA processing; revealing a Conserved Regulators of Kinetoplastid Transcription (CRKT) Complex. Inducible deletion of BDF5 causes global reduction in RNA polymerase II transcription. Our results indicate the requirement of Leishmania to interpret histone acetylation marks through the bromodomain-enriched CRKT complex for normal gene expression and cellular viability.


Assuntos
Leishmania , Acetilação , Animais , Fator V/metabolismo , Histonas/genética , Histonas/metabolismo , Humanos , Leishmania/genética , Leishmania/metabolismo , Lisina/metabolismo , Camundongos
20.
J Virol ; 96(14): e0080622, 2022 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-35862697

RESUMO

Baculoviruses initiate oral infection in the highly alkaline midgut of insects via a group of envelope proteins called per os infectivity factors (PIFs). To date, no high-resolution structural information has been reported for any PIF. Here, we present the crystal structure of the PIF5 ectodomain (PIF5e) from Autographa californica multiple nucleopolyhedrovirus (AcMNPV) at a 2.2-Å resolution. It revealed an open cavity between the N-terminal E1 domain and the C-terminal E2 domain and a cysteine-rich region with three pairs of disulfide bonds in the E2 domain. Multiple conserved intramolecular interactions within PIF5 are essential for maintaining its tertiary structure. Two conserved arginines (Arg8 and Arg74) play critical roles in E1-E2 interactions, and mutagenesis analysis supported their crucial role in oral infection. Importantly, the reduction in the oral infectivity of the Arg8, Arg74, or cysteine mutant viruses was related to the proteolytic cleavage of PIF5 by the endogenous protease embedded in occlusion bodies during alkaline treatment. This suggested that the structural stability of PIF5 under physiological conditions in the insect midgut is critical for baculoviral oral infectivity. IMPORTANCE Per os infection mediated by PIFs is the highly complex mechanism by which baculoviruses initiate infection in insects. Previous studies revealed that multiple PIF proteins form a large PIF complex on the envelope of virions, while PIF5 functions independently of the PIF complex. Here, we report the crystal structure of AcMNPV PIF5e, which, to our knowledge, is the first atomic structure reported for a PIF protein. The structure revealed the precise locations of three previously proposed disulfide bonds and other conserved intramolecular interactions, which are important for the structural stability of PIF5 and are also essential for oral infectivity. These findings advance our understanding of the molecular mechanism of baculovirus oral infection under alkaline conditions.


Assuntos
Cisteína , Fator V , Animais , Baculoviridae/metabolismo , Cisteína/metabolismo , Dissulfetos/metabolismo , Fator V/metabolismo , Insetos , Nucleopoliedrovírus , Spodoptera
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