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1.
Cell ; 150(5): 1055-67, 2012 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-22939628

RESUMO

The type 2 ryanodine receptor/calcium release channel (RyR2), required for excitation-contraction coupling in the heart, is abundant in the brain. Chronic stress induces catecholamine biosynthesis and release, stimulating ß-adrenergic receptors and activating cAMP signaling pathways in neurons. In a murine chronic restraint stress model, neuronal RyR2 were phosphorylated by protein kinase A (PKA), oxidized, and nitrosylated, resulting in depletion of the stabilizing subunit calstabin2 (FKBP12.6) from the channel complex and intracellular calcium leak. Stress-induced cognitive dysfunction, including deficits in learning and memory, and reduced long-term potentiation (LTP) at the hippocampal CA3-CA1 connection were rescued by oral administration of S107, a compound developed in our laboratory that stabilizes RyR2-calstabin2 interaction, or by genetic ablation of the RyR2 PKA phosphorylation site at serine 2808. Thus, neuronal RyR2 remodeling contributes to stress-induced cognitive dysfunction. Leaky RyR2 could be a therapeutic target for treatment of stress-induced cognitive dysfunction.


Assuntos
Transtornos Cognitivos/metabolismo , Canal de Liberação de Cálcio do Receptor de Rianodina/metabolismo , Animais , Cálcio/metabolismo , Hipocampo/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Transtornos de Estresse Traumático/metabolismo
2.
Nature ; 577(7792): 695-700, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31969708

RESUMO

Increased cardiac contractility during the fight-or-flight response is caused by ß-adrenergic augmentation of CaV1.2 voltage-gated calcium channels1-4. However, this augmentation persists in transgenic murine hearts expressing mutant CaV1.2 α1C and ß subunits that can no longer be phosphorylated by protein kinase A-an essential downstream mediator of ß-adrenergic signalling-suggesting that non-channel factors are also required. Here we identify the mechanism by which ß-adrenergic agonists stimulate voltage-gated calcium channels. We express α1C or ß2B subunits conjugated to ascorbate peroxidase5 in mouse hearts, and use multiplexed quantitative proteomics6,7 to track hundreds of proteins in the proximity of CaV1.2. We observe that the calcium-channel inhibitor Rad8,9, a monomeric G protein, is enriched in the CaV1.2 microenvironment but is depleted during ß-adrenergic stimulation. Phosphorylation by protein kinase A of specific serine residues on Rad decreases its affinity for ß subunits and relieves constitutive inhibition of CaV1.2, observed as an increase in channel open probability. Expression of Rad or its homologue Rem in HEK293T cells also imparts stimulation of CaV1.3 and CaV2.2 by protein kinase A, revealing an evolutionarily conserved mechanism that confers adrenergic modulation upon voltage-gated calcium channels.


Assuntos
Canais de Cálcio Tipo L/metabolismo , Proteômica , Receptores Adrenérgicos beta/metabolismo , Animais , Canais de Cálcio Tipo L/química , Canais de Cálcio Tipo N/metabolismo , Microambiente Celular , AMP Cíclico/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Feminino , Células HEK293 , Proteínas Heterotriméricas de Ligação ao GTP/metabolismo , Humanos , Masculino , Camundongos , Proteínas Monoméricas de Ligação ao GTP/metabolismo , Miocárdio/metabolismo , Fosforilação , Domínios Proteicos , Subunidades Proteicas/química , Subunidades Proteicas/metabolismo , Transdução de Sinais , Proteínas ras/química , Proteínas ras/metabolismo
3.
J Transl Med ; 22(1): 37, 2024 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-38191424

RESUMO

BACKGROUND: Aberrant intracellular or intercellular signaling pathways are important mechanisms that contribute to the development and progression of cancer. However, the intercellular communication associated with the development of ccRCC is currently unknown. The purpose of this study was to examine the aberrant tumor cell-to-cell communication signals during the development of ccRCC. METHODS: We conducted an analysis on the scRNA-seq data of 6 ccRCC and 6 normal kidney tissues. This analysis included sub clustering, CNV analysis, single-cell trajectory analysis, cell-cell communication analysis, and transcription factor analysis. Moreover, we performed validation tests on clinical samples using multiplex immunofluorescence. RESULTS: This study identified eleven aberrantly activated intercellular signaling pathways in tumor clusters from ccRCC samples. Among these, two of the majors signaling molecules, MIF and SPP1, were mainly secreted by a subpopulation of cancer stem cells. This subpopulation demonstrated high expression levels of the cancer stem cell markers POU5F1 and CD44 (POU5F1hiCD44hiE.T), with the transcription factor POU5F1 regulating the expression of SPP1. Further research demonstrated that SPP1 binds to integrin receptors on the surface of target cells and promotes ccRCC development and progression by activating potential signaling mechanisms such as ILK and JAK/STAT. CONCLUSION: Aberrantly activated tumor intercellular signaling pathways promote the development and progression of ccRCC. The cancer stem cell subpopulation (POU5F1hiCD44hiE.T) promotes malignant transformation and the development of a malignant phenotype by releasing aberrant signaling molecules and interacting with other tumor cells.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Humanos , Carcinoma de Células Renais/genética , Transcriptoma/genética , Transdução de Sinais/genética , Comunicação Celular , Neoplasias Renais/genética
4.
Environ Res ; 250: 118520, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38401683

RESUMO

The sedentary and less active lifestyle of modern college students has a significant impact on the physical and mental well-being of the college community. Campus Green Spaces (GSs) are crucial in promoting physical activity and improving students' health. However, previous research has focused on evaluating campuses as a whole, without considering the diverse spatial scenarios within the campus environment. Accordingly, this study focused on the young people's residential scenario in university and constructed a framework including a comprehensive set of objective and subjective GSs exposure metrics. A systematic, objective exposure assessment framework ranging from 2D (GSs areas), and 2.5D (GSs visibility) to 3D (GSs volume) was innovatively developed using spatial analysis, deep learning technology, and unmanned aerial vehicle (UAV) measurement technology. Subjective exposure metrics incorporated GSs visiting frequency, GSs visiting duration, and GSs perceived quality. Our cross-sectional study was based on 820 university students in Nanjing, China. Subjective measures of GSs exposure, physical activity, and health status were obtained through self-reported questionnaires. The Generalized Linear Model (GLM) was used to evaluate the associations between GSs exposure, physical activity, and perceived health. Physical activity and social cohesion were considered as mediators, and path analysis based on Structural Equation Modeling (SEM) was used to disentangle the mechanisms linking GSs exposure to the health status of college students. We found that (1) 2D indicator suggested significant associations with health in the 100m buffer, and the potential underlying mechanisms were: GSs area → Physical activity → Social cohesion → Physical health → Mental health; GSs area → Physical activity → Social cohesion → Mental health. (2) Subjective GSs exposure indicators were more relevant in illustrating exposure-response relationships than objective ones. This study can clarify the complex nexus and mechanisms between campus GSs, physical activity, and health, and provide a practical reference for health-oriented campus GSs planning.


Assuntos
Exercício Físico , Estudantes , Humanos , Estudantes/psicologia , Masculino , Adulto Jovem , Feminino , Universidades , Estudos Transversais , China , Adolescente , Nível de Saúde
5.
Circ Res ; 128(1): 76-88, 2021 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-33086983

RESUMO

RATIONALE: Changing activity of cardiac CaV1.2 channels under basal conditions, during sympathetic activation, and in heart failure is a major determinant of cardiac physiology and pathophysiology. Although cardiac CaV1.2 channels are prominently upregulated via activation of PKA (protein kinase A), essential molecular details remained stubbornly enigmatic. OBJECTIVE: The primary goal of this study was to determine how various factors converging at the CaV1.2 I-II loop interact to regulate channel activity under basal conditions, during ß-adrenergic stimulation, and in heart failure. METHODS AND RESULTS: We generated transgenic mice with expression of CaV1.2 α1C subunits with (1) mutations ablating interaction between α1C and ß-subunits, (2) flexibility-inducing polyglycine substitutions in the I-II loop (GGG-α1C), or (3) introduction of the alternatively spliced 25-amino acid exon 9* mimicking a splice variant of α1C upregulated in the hypertrophied heart. Introducing 3 glycine residues that disrupt a rigid IS6-α-interaction domain helix markedly reduced basal open probability despite intact binding of CaVß to α1C I-II loop and eliminated ß-adrenergic agonist stimulation of CaV1.2 current. In contrast, introduction of the exon 9* splice variant in the α1C I-II loop, which is increased in ventricles of patients with end-stage heart failure, increased basal open probability but did not attenuate stimulatory response to ß-adrenergic agonists when reconstituted heterologously with ß2B and Rad or transgenically expressed in cardiomyocytes. CONCLUSIONS: Ca2+ channel activity is dynamically modulated under basal conditions, during ß-adrenergic stimulation, and in heart failure by mechanisms converging at the α1C I-II loop. CaVß binding to α1C stabilizes an increased channel open probability gating mode by a mechanism that requires an intact rigid linker between the ß-subunit binding site in the I-II loop and the channel pore. Release of Rad-mediated inhibition of Ca2+ channel activity by ß-adrenergic agonists/PKA also requires this rigid linker and ß-binding to α1C.


Assuntos
Agonistas Adrenérgicos beta/farmacologia , Canais de Cálcio Tipo L/metabolismo , Ativação do Canal Iônico/efeitos dos fármacos , Miócitos Cardíacos/efeitos dos fármacos , Proteínas ras/metabolismo , Animais , Canais de Cálcio Tipo L/genética , Células HEK293 , Insuficiência Cardíaca/genética , Insuficiência Cardíaca/metabolismo , Insuficiência Cardíaca/fisiopatologia , Humanos , Potenciais da Membrana , Camundongos Transgênicos , Mutação , Miócitos Cardíacos/metabolismo , Fosforilação , Conformação Proteica , Coelhos , Relação Estrutura-Atividade , Proteínas ras/genética
6.
Sensors (Basel) ; 22(18)2022 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-36146155

RESUMO

The imaging range of traditional plane wave imaging is usually limited by the directivity of the plane wave. In this paper, a multi spherical wave imaging method based on an ultrasonic array is proposed, which radiates both compression and shear waves in a solid medium to form the multi spherical wave. Firstly, excitation characteristics of the multi spherical wave are analyzed theoretically and the calculation method of echo delay of multi spherical wave imaging is derived. Multi spherical wave imaging is compared with conventional ultrasonic plane wave imaging by designing experiments. Compared with ultrasonic plane wave imaging, multi spherical wave imaging is not limited to the size of the transducer and can greatly improve the detection range. In addition, compared with the multi plane wave imaging method, the multi spherical wave imaging algorithm is relatively simple, fast, and has high application value.


Assuntos
Compressão de Dados , Ultrassom , Algoritmos , Imagens de Fantasmas , Ultrassonografia
8.
Proc Natl Acad Sci U S A ; 114(34): 9194-9199, 2017 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-28784807

RESUMO

Calcium influx through the voltage-dependent L-type calcium channel (CaV1.2) rapidly increases in the heart during "fight or flight" through activation of the ß-adrenergic and protein kinase A (PKA) signaling pathway. The precise molecular mechanisms of ß-adrenergic activation of cardiac CaV1.2, however, are incompletely known, but are presumed to require phosphorylation of residues in α1C and C-terminal proteolytic cleavage of the α1C subunit. We generated transgenic mice expressing an α1C with alanine substitutions of all conserved serine or threonine, which is predicted to be a potential PKA phosphorylation site by at least one prediction tool, while sparing the residues previously shown to be phosphorylated but shown individually not to be required for ß-adrenergic regulation of CaV1.2 current (17-mutant). A second line included these 17 putative sites plus the five previously identified phosphoregulatory sites (22-mutant), thus allowing us to query whether regulation requires their contribution in combination. We determined that acute ß-adrenergic regulation does not require any combination of potential PKA phosphorylation sites conserved in human, guinea pig, rabbit, rat, and mouse α1C subunits. We separately generated transgenic mice with inducible expression of proteolytic-resistant α1C Prevention of C-terminal cleavage did not alter ß-adrenergic stimulation of CaV1.2 in the heart. These studies definitively rule out a role for all conserved consensus PKA phosphorylation sites in α1C in ß-adrenergic stimulation of CaV1.2, and show that phosphoregulatory sites on α1C are not redundant and do not each fractionally contribute to the net stimulatory effect of ß-adrenergic stimulation. Further, proteolytic cleavage of α1C is not required for ß-adrenergic stimulation of CaV1.2.


Assuntos
Adrenérgicos/metabolismo , Canais de Cálcio Tipo L/química , Canais de Cálcio Tipo L/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Miocárdio/metabolismo , Animais , Canais de Cálcio Tipo L/genética , Proteínas Quinases Dependentes de AMP Cíclico/genética , Cobaias , Humanos , Camundongos , Camundongos Transgênicos , Fosforilação , Domínios Proteicos , Proteólise , Coelhos , Ratos
9.
Acta Orthop Belg ; 85(2): 182-191, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31315008

RESUMO

Most compound acetabular fractures involving both the anterior and posterior columns are caused by high-energy injuries. Patients with compound acetabular fractures are often in critical or poor condition and cannot tolerate major surgery. This study aims to investigate the effectiveness of an ilioischial plate in treating compound acetabular fractures. A consecutive series of 40 patients with complex acetabular fractures were surgically treated and retrospectively reviewed. A modified Stoppa approach in combination with an iliac fossa approach was used. In all of the cases, the anterior column was stabilized with reconstruction plates for the iliac wing and along the iliopectineal line to the pubis. The posterior column was fixed either with the newly developed ilioischial plate running from the ilium to the ischial ramus or with standard fixation techniques. These included either conventional posterior column screws or quadrilateral plate fixation. Patients were divided into an experimental group (ilioischial plate for posterior column fixation) and a control group (standard fixation techniques). In both groups, we found that 90% of all reductions were good to excellent. According to the modified Merle Aubigne and Postel scoring system, the percentage of good to excellent was 85% in the experimental group as compared to 80% in the control group. Compared with the control group, physical function (PF), role physical (RP) and social function (SF) were significantly better in the experimental group (P<0.05). Fracture healing was achieved in all patients. By using the modified Stoppa approach combined with the iliac fossa approach, the ilioischial plate can be directly fixed to the posterior column and the ilium to stabilize the posterior column in patients with complex acetabular fractures.


Assuntos
Acetábulo/lesões , Fixação Interna de Fraturas/métodos , Fraturas Ósseas/cirurgia , Ílio/cirurgia , Acetábulo/cirurgia , Adulto , Placas Ósseas , Parafusos Ósseos , Feminino , Consolidação da Fratura/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento
10.
Zhonghua Nan Ke Xue ; 24(7): 602-607, 2018 07.
Artigo em Zh | MEDLINE | ID: mdl-30173442

RESUMO

Objective: To identify genetic susceptibility genes and the loci of their single nucleotide polymorphisms (SNPs) in patients with testicular germ cell tumor (TGCT) and provide some new ideas for the prediction, diagnosis and treatment of TGCT. METHODS: We identified 41 SNP loci of TGCT-related genetic susceptibility genes from the literature published abroad. Using the iMLDRTM genotyping technique, we examined the SNP loci of the genetic susceptibility genes in the blood samples from 76 TGCT patients (aged 16-68 years) and 148 healthy men (aged 22-61 years) in China and analyzed their correlation with TGCT. RESULTS: In China, TGCT was found to be correlated with the SNP loci rs2978381, rs10146204, rs12435857 and rs1256063 of the ESR2 gene, rs9397080 of the ESR1 gene, rs11202586 of the PTEN gene, rs2606345 and rs4646903 of the CYP1A1 gene, and rs1456432 of the CYP19A1 gene. CONCLUSIONS: The results of our study indicated some difference in the positive SNP loci of the TGCT patients between Chinese and foreign cohorts as well as in different groups in China.


Assuntos
Predisposição Genética para Doença , Neoplasias Embrionárias de Células Germinativas/genética , Polimorfismo de Nucleotídeo Único/genética , Neoplasias Testiculares/genética , Adolescente , Adulto , Idoso , Estudos de Casos e Controles , China , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Embrionárias de Células Germinativas/diagnóstico , Neoplasias Embrionárias de Células Germinativas/terapia , Neoplasias Testiculares/diagnóstico , Neoplasias Testiculares/terapia , Adulto Jovem
11.
Nat Chem Biol ; 10(2): 133-40, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24316735

RESUMO

Autophagy is linked to cell death, yet the associated mechanisms are largely undercharacterized. We discovered that melanoma, which is generally resistant to drug-induced apoptosis, can undergo autophagic cell death with the participation of orphan nuclear receptor TR3. A sequence of molecular events leading to cellular demise is launched by a specific chemical compound, 1-(3,4,5-trihydroxyphenyl)nonan-1-one, newly acquired from screening a library of TR3-targeting compounds. The autophagic cascade comprises TR3 translocation to mitochondria through interaction with the mitochondrial outer membrane protein Nix, crossing into the mitochondrial inner membrane through Tom40 and Tom70 channel proteins, dissipation of mitochondrial membrane potential by the permeability transition pore complex ANT1-VDAC1 and induction of autophagy. This process leads to excessive mitochondria clearance and irreversible cell death. It implicates a new approach to melanoma therapy through activation of a mitochondrial signaling pathway that integrates a nuclear receptor with autophagy for cell death.


Assuntos
Autofagia , Cetonas/química , Mitocôndrias/fisiologia , Membro 1 do Grupo A da Subfamília 4 de Receptores Nucleares/metabolismo , Pirogalol/análogos & derivados , Transdução de Sinais , Animais , Linhagem Celular Tumoral , Cristalografia por Raios X , Modelos Animais de Doenças , Humanos , Cetonas/farmacologia , Melanoma/tratamento farmacológico , Proteínas de Membrana/metabolismo , Camundongos , Conformação Proteica , Proteínas Proto-Oncogênicas/metabolismo , Pirogalol/química , Pirogalol/farmacologia , Proteínas Supressoras de Tumor/metabolismo
12.
Circ Res ; 111(6): 708-17, 2012 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-22828895

RESUMO

RATIONALE: Atrial fibrillation (AF) is the most common cardiac arrhythmia, however the mechanism(s) causing AF remain poorly understood and therapy is suboptimal. The ryanodine receptor (RyR2) is the major calcium (Ca2+) release channel on the sarcoplasmic reticulum (SR) required for excitation-contraction coupling in cardiac muscle. OBJECTIVE: In the present study, we sought to determine whether intracellular diastolic SR Ca2+ leak via RyR2 plays a role in triggering AF and whether inhibiting this leak can prevent AF. METHODS AND RESULTS: We generated 3 knock-in mice with mutations introduced into RyR2 that result in leaky channels and cause exercise induced polymorphic ventricular tachycardia in humans [catecholaminergic polymorphic ventricular tachycardia (CPVT)]. We examined AF susceptibility in these three CPVT mouse models harboring RyR2 mutations to explore the role of diastolic SR Ca2+ leak in AF. AF was stimulated with an intra-esophageal burst pacing protocol in the 3 CPVT mouse models (RyR2-R2474S+/-, 70%; RyR2-N2386I+/-, 60%; RyR2-L433P+/-, 35.71%) but not in wild-type (WT) mice (P<0.05). Consistent with these in vivo results, there was a significant diastolic SR Ca2+ leak in atrial myocytes isolated from the CPVT mouse models. Calstabin2 (FKBP12.6) is an RyR2 subunit that stabilizes the closed state of RyR2 and prevents a Ca2+ leak through the channel. Atrial RyR2 from RyR2-R2474S+/- mice were oxidized, and the RyR2 macromolecular complex was depleted of calstabin2. The Rycal drug S107 stabilizes the closed state of RyR2 by inhibiting the oxidation/phosphorylation induced dissociation of calstabin2 from the channel. S107 reduced the diastolic SR Ca2+ leak in atrial myocytes and decreased burst pacing-induced AF in vivo. S107 did not reduce the increased prevalence of burst pacing-induced AF in calstabin2-deficient mice, confirming that calstabin2 is required for the mechanism of action of the drug. CONCLUSIONS: The present study demonstrates that RyR2-mediated diastolic SR Ca2+ leak in atrial myocytes is associated with AF in CPVT mice. Moreover, the Rycal S107 inhibited diastolic SR Ca2+ leak through RyR2 and pacing-induced AF associated with CPVT mutations.


Assuntos
Fibrilação Atrial/metabolismo , Cálcio/metabolismo , Modelos Animais de Doenças , Canal de Liberação de Cálcio do Receptor de Rianodina/metabolismo , Taquicardia Ventricular/metabolismo , Animais , Fibrilação Atrial/genética , Fibrilação Atrial/fisiopatologia , Cafeína/farmacologia , Estimulação Cardíaca Artificial , Células Cultivadas , Eletrocardiografia/efeitos dos fármacos , Epinefrina/farmacologia , Técnicas de Introdução de Genes , Coração/efeitos dos fármacos , Coração/fisiopatologia , Humanos , Immunoblotting , Camundongos , Camundongos Knockout , Mutação , Miócitos Cardíacos/citologia , Miócitos Cardíacos/metabolismo , Condicionamento Físico Animal/fisiologia , Canal de Liberação de Cálcio do Receptor de Rianodina/genética , Retículo Sarcoplasmático/efeitos dos fármacos , Retículo Sarcoplasmático/metabolismo , Taquicardia Ventricular/genética , Taquicardia Ventricular/fisiopatologia , Proteínas de Ligação a Tacrolimo/genética , Proteínas de Ligação a Tacrolimo/metabolismo , Tiazepinas/farmacologia
13.
J Assist Reprod Genet ; 31(3): 371-7, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24390680

RESUMO

PURPOSE: Polycystic ovary syndrome (PCOS) is a common endocrine disorder disease among women in reproductive-age. Since follicle stimulating hormone (FSH) exerts important biological functions, the association between PCOS and FSH receptor (FSHR) polymorphisms attracts wide attention. The aim of this study was to evaluate whether polymorphisms of FSHR at 307 and 680 codons are associated with PCOS patients in China. METHODS: Patients with PCOS (n = 215) and controls (n = 205) were recruited from Shanxi Province in north China. They are Han ethnics. Genomic DNA was isolated from the venous blood. The Ala307Thr and Ser680Asn polymorphisms of FSHR were analyzed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and direct DNA sequencing. RESULTS: The distributions of genotype and allele of Ala307Thr and Ser680Asn polymorphisms of FSHR were not statistically different between the PCOS patients and the controls. Analysis of the frequency of FSHR polymorphisms showed no statistical difference among the PCOS patients with different obesity standards. Although there were no statistical differences in the most of the endocrine parameters including LH, LH/FSH, E2, P and T as well as the clinical pregnancy rate, there were significant differences in the levels of FSH and PRL among PCOS patients carrying different genotypes of Ala307Thr and Ser680Asn polymorphisms. CONCLUSION: The Ala307Thr and Ser680Asn polymorphisms of FSHR are not associated with PCOS in Han ethnic Chinese women in north China. The FSHR polymorphisms was related to the levels of FSH and PRL but not other PCOS-associated endocrine hormones as well as clinical pregnancy rate in PCOS patients of Han Chinese ethnical population.


Assuntos
Estudos de Associação Genética , Predisposição Genética para Doença , Síndrome do Ovário Policístico/genética , Receptores do FSH/genética , Adulto , Alelos , China , Feminino , Hormônio Foliculoestimulante/sangue , Humanos , Síndrome do Ovário Policístico/sangue , Polimorfismo de Nucleotídeo Único , Gravidez
14.
Front Plant Sci ; 15: 1367121, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39086912

RESUMO

Introduction: The research on plant leaf morphology is of great significance for understanding the development and evolution of plant organ morphology. As a relict plant, the G. biloba leaf morphology typically exhibits bifoliate and peltate forms. However, throughout its long evolutionary history, Ginkgo leaves have undergone diverse changes. Methods: This study focuses on the distinct "trumpet" leaves and normal fan-shaped leaves of G. biloba for analysis of their phenotypes, photosynthetic activity, anatomical observations, as well as transcriptomic and metabolomic analyses. Results: The results showed that trumpet-shaped G. biloba leaves have fewer cells, significant morphological differences between dorsal and abaxial epidermal cells, leading to a significantly lower net photosynthetic rate. Additionally, this study found that endogenous plant hormones such as GA, auxin, and JA as well as metabolites such as flavonoids and phenolic acids play roles in the formation of trumpet-shaped G. biloba leaves. Moreover, the experiments revealed the regulatory mechanisms of various key biological processes and gene expressions in the trumpet-shaped leaves of G. biloba. Discussion: Differences in the dorsal and abdominal cells of G. biloba leaves can cause the leaf to curl, thus reducing the overall photosynthetic efficiency of the leaves. However, the morphology of plant leaves is determined during the primordia leaf stage. In the early stages of leaf development, the shoot apical meristem (SAM) determines the developmental morphology of dicotyledonous plant leaves. This process involves the activity of multiple gene families and small RNAs. The establishment of leaf morphology is complexly regulated by various endogenous hormones, including the effect of auxin on cell walls. Additionally, changes in intracellular ion concentrations, such as fluctuations in Ca2+ concentration, also affect cell wall rigidity, thereby influencing leaf growth morphology.

15.
J Clin Invest ; 134(5)2024 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-38227371

RESUMO

The ability to fight or flee from a threat relies on an acute adrenergic surge that augments cardiac output, which is dependent on increased cardiac contractility and heart rate. This cardiac response depends on ß-adrenergic-initiated reversal of the small RGK G protein Rad-mediated inhibition of voltage-gated calcium channels (CaV) acting through the Cavß subunit. Here, we investigate how Rad couples phosphorylation to augmented Ca2+ influx and increased cardiac contraction. We show that reversal required phosphorylation of Ser272 and Ser300 within Rad's polybasic, hydrophobic C-terminal domain (CTD). Phosphorylation of Ser25 and Ser38 in Rad's N-terminal domain (NTD) alone was ineffective. Phosphorylation of Ser272 and Ser300 or the addition of 4 Asp residues to the CTD reduced Rad's association with the negatively charged, cytoplasmic plasmalemmal surface and with CaVß, even in the absence of CaVα, measured here by FRET. Addition of a posttranslationally prenylated CAAX motif to Rad's C-terminus, which constitutively tethers Rad to the membrane, prevented the physiological and biochemical effects of both phosphorylation and Asp substitution. Thus, dissociation of Rad from the sarcolemma, and consequently from CaVß, is sufficient for sympathetic upregulation of Ca2+ currents.


Assuntos
Adrenérgicos , Proteínas Monoméricas de Ligação ao GTP , Humanos , Adrenérgicos/metabolismo , Adrenérgicos/farmacologia , Cálcio/metabolismo , Canais de Cálcio Tipo L/metabolismo , Miócitos Cardíacos/metabolismo , Proteínas Monoméricas de Ligação ao GTP/metabolismo , Arritmias Cardíacas/metabolismo
16.
J Mol Cell Cardiol ; 64: 120-3, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24041536

RESUMO

Abnormalities in intracellular Ca(2+) signaling have been proposed to play an essential role in the pathophysiology of atrial arrhythmias. However, a direct observation of intracellular Ca(2+) in atrial myocytes during atrial arrhythmias is lacking. Here, we have developed an ex vivo model of simultaneous Ca(2+) imaging and electrocardiographic recording in cardiac atria. Using this system we were able to record atrial arrhythmic intracellular Ca(2+) activities. Our results indicate that atrial arrhythmias can be tightly linked to intracellular Ca(2+) waves and Ca(2+) alternans. Moreover, we applied this strategy to analyze Ca(2+) signals in the hearts of WT and knock-in mice harboring a 'leaky' type 2 ryanodine receptor (RyR2-R2474S). We showed that sarcoplasmic reticulum (SR) Ca(2+) leak increases the susceptibility to Ca(2+) alternans and Ca(2+) waves increasing the incidence of atrial arrhythmias. Reduction of SR Ca(2+) leak via RyR2 by acute treatment with S107 reduced both Ca(2+) alternans and Ca(2+) waves, and prevented atrial arrhythmias.


Assuntos
Arritmias Cardíacas/diagnóstico , Arritmias Cardíacas/metabolismo , Cálcio/metabolismo , Átrios do Coração/metabolismo , Átrios do Coração/fisiopatologia , Impressão Molecular , Animais , Arritmias Cardíacas/genética , Sinalização do Cálcio , Modelos Animais de Doenças , Eletrocardiografia , Técnicas In Vitro , Espaço Intracelular/metabolismo , Camundongos , Camundongos Knockout , Impressão Molecular/métodos , Miócitos Cardíacos/metabolismo , Canal de Liberação de Cálcio do Receptor de Rianodina/genética , Canal de Liberação de Cálcio do Receptor de Rianodina/metabolismo
17.
Biotechnol Genet Eng Rev ; : 1-11, 2023 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-36606759

RESUMO

OBJECTIVE: To investigate the correlation between methylenetetrahydrofolate reductase (MTHFR) gene-specific methylation and recurrent spontaneous abortion (RSA). METHODS: A total of 50 RSA patients who visited our hospital were recruited in the study group; 50 multiparous women who underwent physical examinations during the same period were enrolled in the control group. The levels of homocysteine, folic acid, and vitamin B12 and their MTHFR gene polymorphism and specific methylation were measured in both groups. The Logistic regression equation was used to analyze the correlation between MTHFR gene-specific methylation and RSA. RESULTS: The methylated allele MM was not found in the control group, and the frequency in the study group was 1.19%. The frequency of the MU genotype in the study group 32.93% was higher than that in the control group 12.45%. The frequency of methylated alleles of CC and CT genotypes carrying MTHFR C677T polymorphism in the study group was higher than that in the control group (P < 0.05). There was no significant difference in the TT genotype between the two groups (P > 0.05). Multivariate Logistic regression analysis exhibited that patients with methylated alleles of CC genotype had a risk of RSA increased by 1.167 times, and the risk increased by 2.500 times in patients with methylated alleles of CT genotype (P < 0.05). 83.33% of RSA patients carrying methylated alleles affected hyperhomocysteinemia. In patients with elevated homocysteine levels, the risk of RSA caused by methylated allele was significantly increased by 7.321 times. CONCLUSION: MTHFR gene-specific methylation can significantly increase the risk of RSA.

18.
Asian J Surg ; 46(9): 3607-3613, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37147255

RESUMO

BACKGROUND: The survival benefit of partial nephrectomy (PN) in pT3a RCC patients is controversial. Here we aimed to explore the potential benefit of PN for pT3aN0M0 renal cell carcinoma (RCC). MATERIAL AND METHODS: Data of patients with pT3aN0M0 RCC who were diagnosed between 2010 and 2012 in the National Cancer Institute Surveillance, Epidemiology, and End Results (SEER) database were retrospectively collected. Overall survival (OS) and cancer specific survival (CSS) were compared using a Cox proportional hazards model between PN and radical nephrectomy (RN) in pT3aN0M0 RCC. Propensity score (-adjusted, -stratified, -weighted, and -matched) analyses were performed to control for imbalances in individual risk factors. RESULTS: A total of 1277 patients with pT3aN0M0 RCC were identified, of whom 200 patients were treated with PN and 1077 patients were RN. PN showed favorable OS and CSS in 0-4 cm pT3aN0M0 RCC (P < 0.05), and similar OS and CSS in 4-7 cm pT3aN0M0 RCC, compared with RN using un-adjusted analyses. The Propensity score analyses further demonstrated the survival benefit of PN compared with the RN in 0-4 cm pT3aN0M0 RCC (P < 0.05). CONCLUSIONS: In this retrospective study, PN was associated with improved survival compared with RN in 0-4 cm pT3aN0M0 RCC. Moreover, survival was comparable between PN and RN in 4-7 cm pT3aN0M0 RCC. These data provided evidence that PN could be an alternative choice for T3aN0M0 RCC less than 7 cm. Particularly, patients with 0-4 cm pT3aN0M0 RCC might benefit from PN.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Humanos , Carcinoma de Células Renais/cirurgia , Neoplasias Renais/patologia , Estudos Retrospectivos , Pontuação de Propensão , Nefrectomia/métodos , Estadiamento de Neoplasias , Resultado do Tratamento
19.
J Dig Dis ; 24(1): 2-9, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36908189

RESUMO

OBJECTIVES: The impact of ineffective esophageal motility (IEM) on gastroesophageal reflux disease (GERD) remains unknown, and abnormal esophageal motility often coexists with abnormal gastric motility. We aimed to investigate the role of IEM in GERD and its relationship with gastric electrical activity. METHODS: Patients diagnosed as GERD based on GERD-questionnaire score ≥8 in our hospital from January 2020 to June 2022 were included. All patients underwent 24-h multichannel intraluminal impedance-pH monitoring, high-resolution manometry, and electrogastrogram and were categorized into the normal esophageal motility (NEM) and IEM groups, respectively. Reflux characteristics and gastric electric activity were compared between the two groups, and the correlation between gastric electric activity and reflux was analyzed. RESULTS: Acid exposure time, total reflux episodes, and DeMeester score in the IEM group were higher than those in the NEM group. Distal mean nocturnal baseline impedance was significantly lower in the IEM group. Compared with the NEM group, the power ratio (PR) of fundus, antrum and pylorus and premeal and postmeal normal wave ratio of antrum were significantly lower in IEM. The total reflux episodes were negatively correlated with the PR of fundus and pylorus, and the DeMeester score was negatively correlated with the PR of corpus and pylorus. CONCLUSIONS: IEM may lead to increased reflux, resulting in esophageal mucosal damage. There may be consistency between abnormal esophageal motility and gastric motility.


Assuntos
Transtornos da Motilidade Esofágica , Refluxo Gastroesofágico , Humanos , Monitoramento do pH Esofágico/métodos , Refluxo Gastroesofágico/diagnóstico , Manometria/métodos , Estômago
20.
Nat Cardiovasc Res ; 1(5): 1-13, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35662881

RESUMO

Voltage-gated sodium (Nav1.5) channels support the genesis and brisk spatial propagation of action potentials in the heart. Disruption of NaV1.5 inactivation results in a small persistent Na influx known as late Na current (I Na,L), which has emerged as a common pathogenic mechanism in both congenital and acquired cardiac arrhythmogenic syndromes. Here, using low-noise multi-channel recordings in heterologous systems, LQTS3 patient-derived iPSCs cardiomyocytes, and mouse ventricular myocytes, we demonstrate that the intracellular fibroblast growth factor homologous factors (FHF1-4) tune pathogenic I Na,L in an isoform-specific manner. This scheme suggests a complex orchestration of I Na,L in cardiomyocytes that may contribute to variable disease expressivity of NaV1.5 channelopathies. We further leverage these observations to engineer a peptide-inhibitor of I Na,L with a higher efficacy as compared to a well-established small-molecule inhibitor. Overall, these findings lend insights into molecular mechanisms underlying FHF regulation of I Na,L in pathophysiology and outline potential therapeutic avenues.

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