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1.
EMBO Rep ; 24(11): e56864, 2023 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-37575008

RESUMO

Kinesin-driven intracellular transport is essential for various cell biological events and thus plays a crucial role in many pathological processes. However, little is known about the molecular basis of the specific and dynamic cargo-binding mechanism of kinesins. Here, an integrated structural analysis of the KIF3/KAP3 and KIF3/KAP3-APC complexes unveils the mechanism by which KIF3/KAP3 can dynamically grasp APC in a two-step manner, which suggests kinesin-cargo recognition dynamics composed of cargo loading, locking, and release. Our finding is the first demonstration of the two-step cargo recognition and stabilization mechanism of kinesins, which provides novel insights into the intracellular trafficking machinery.


Assuntos
Comunicação Celular , Cinesinas , Cinesinas/metabolismo , Transporte Biológico , Microtúbulos/metabolismo
2.
Soft Matter ; 20(19): 3931-3941, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38668863

RESUMO

This study explores the opto-mechanical response of cholesteric liquid crystal elastomers (CLCEs) subjected to uniaxial stretching along the x-axis, perpendicular to their helical z-axis. A definitive crossover is observed in the strain (εx) dependencies of various optical and mechanical properties, such as the transmission spectra, degree of mesogen orientation, Poisson's ratios, and tensile stress. At low strains, CLCEs exhibit a blue shift in the selective reflection band due to a reduction in the helical pitch, accompanied by a decrease in reflection selectivity for circularly polarized light. Beyond a certain critical strain further pitch alterations halt. This strain regime is marked by substantial anisotropic lateral contractions without any z-axis contraction, as indicated by a Poisson's ratio (µxz) of zero. Within this intermediate strain regime, local directors predominantly reorient towards the x-direction within the xy-plane, resulting in a quasi-plateau of tensile stress. Approaching a higher critical strain a complete loss of reflective selectivity occurs. Past this threshold, while the mechanical responses resemble those of isotropic conventional rubber, they retain a periodic structure albeit without phase chirality. These observed features are accounted for by the Mao-Terentjev-Warner model, especially when the network anisotropy parameter is adjusted to match the critical strain magnitude associated with the cessation of selective reflection.

3.
Neurourol Urodyn ; 43(1): 267-275, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37916422

RESUMO

OBJECTIVES: We examined sex differences of lower urinary tract function and molecular mechanisms in mice with and without spinal cord injury (SCI). METHODS: SCI was induced by Th8-9 spinal cord transection in male and female mice. We evaluated cystometrograms (CMG) and electromyography (EMG) of external urethral sphincter (EUS) at 6 weeks after SCI in spinal intact (SI) and SCI mice. The mRNA levels of Piezo2 and TRPV1 were measured in L6-S1 dorsal root ganglia (DRG). Protein levels of nerve growth factor (NGF) in the bladder mucosa was evaluated using an enzyme-linked immunosorbent assay. RESULTS: Sex differences were found in the EUS behavior during voiding as voiding events in female mice with or without SCI occurred during EUS relaxation periods without EUS bursting activity whereas male mice with or without SCI urinated during EUS bursting activity in EMG recordings. In both sexes, SCI decreased voiding efficiency along with increased tonic EUS activities evident as reduced EUS relaxation time in females and longer active periods of EUS bursting activity in males. mRNA levels of Piezo2 and TRPV1 of DRG in male and female SCI mice were significantly upregulated compared with SI mice. NGF in the bladder mucosa showed a significant increase in male and female SCI mice compared with SI mice. However, there were no significant differences in Piezo2 or TRPV1 levels in DRG or NGF protein levels in the bladder mucosa between male and female SCI mice. CONCLUSIONS: We demonstrated that female and male mice voided during EUS relaxation and EUS bursting activity, respectively. Also, upregulation of TRPV1 and Piezo2 in L6-S1 DRG and NGF in the bladder could be involved in SCI-induced lower urinary tract dysfunction in both sexes of mice.


Assuntos
Traumatismos da Medula Espinal , Bexiga Urinária , Masculino , Feminino , Camundongos , Animais , Caracteres Sexuais , Fator de Crescimento Neural/genética , Fator de Crescimento Neural/metabolismo , Uretra , RNA Mensageiro , Medula Espinal
4.
Int J Urol ; 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38884570

RESUMO

OBJECTIVES: To investigate roles of brain carbon monoxide (CO), an endogenous gasotransmitter, in regulation of the rat micturition reflex. METHODS: In urethane-anesthetized (0.8 g/kg, ip) male rats, evaluation of urodynamic parameters was started 1 h before intracerebroventricular administration of CORM-3 (CO donor) or ZnPP (non-selective inhibitor of heme oxygenase, a CO producing enzyme) and continued for 2 h after the administration. We also investigated effects of centrally pretreated SR95531 (GABAA receptor antagonist) or SCH50911 (GABAB receptor antagonist) on the CORM-3-induced response. RESULTS: CORM-3 significantly prolonged intercontraction intervals (ICIs) without changing maximal voiding pressure (MVP), while ZnPP significantly shortened ICI and reduced single-voided volume and bladder capacity without affecting MVP, post-voided residual volume, or voiding efficiency. The ZnPP-induced ICI shortening was reversed by CORM-3. The CORM-3-induced ICI prolongation was significantly attenuated by centrally pretreated SR95531 or SCH50911, respectively. CONCLUSIONS: Brain CO can suppress the rat micturition reflex through brain γ-aminobutyric acid (GABA) receptors.

5.
J Am Chem Soc ; 145(41): 22563-22576, 2023 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-37796243

RESUMO

Polymorphism, a phenomenon whereby disparate self-assembled products can be formed from identical molecules, has incited interest in the field of supramolecular polymers. Conventionally, the monomers that constitute supramolecular polymers are engineered to facilitate one-dimensional aggregation and, consequently, their polymorphism surfaces primarily when the states of assembly differ significantly. This engenders polymorphs of divergent dimensionalities such as one- and two-dimensional aggregates. Notwithstanding, realizing supramolecular polymer polymorphism, wherein polymorphs maintain one-dimensional aggregation, persists as a daunting challenge. In this work, we expound upon the manifestation of two supramolecular polymer polymorphs formed from a large discotic supramolecular monomer (rosette), which consists of six hydrogen-bonded molecules with an extended π-conjugated core. These polymorphs are generated in mixtures of chloroform and methylcyclohexane, attributable to distinctly different disc stacking arrangements. The face-to-face (minimal displacement) and offset (large displacement) stacking arrangements can be predicated on their distinctive photophysical properties. The face-to-face stacking results in a twisted helix structure. Conversely, the offset stacking induces inherent curvature in the supramolecular fiber, thereby culminating in a hollow helical coil (helicoid). While both polymorphs exhibit bistability in nonpolar solvent compositions, the face-to-face stacking attains stability purely in a kinetic sense within a polar solvent composition and undergoes conversion into offset stacking through a dislocation of stacked rosettes. This occurs without the dissociation and nucleation of monomers, leading to unprecedented helicoidal folding of supramolecular polymers. Our findings augment our understanding of supramolecular polymer polymorphism, but they also highlight a distinctive method for achieving helicoidal folding in supramolecular polymers.

6.
Nature ; 545(7653): 193-198, 2017 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-28467821

RESUMO

The lipid bilayer has so far eluded visualization by conventional crystallographic methods, severely limiting our understanding of phospholipid- and protein-phospholipid interactions. Here we describe electron density maps for crystals of Ca2+-ATPase in four different states obtained by X-ray solvent contrast modulation. These maps resolve the entire first layer of phospholipids surrounding the transmembrane helices, although less than half of them are hydrogen-bonded to protein residues. Phospholipids follow the movements of associated residues, causing local distortions and changes in thickness of the bilayer. Unexpectedly, the entire protein tilts during the reaction cycle, governed primarily by a belt of Trp residues, to minimize energy costs accompanying the large perpendicular movements of the transmembrane helices. A class of Arg residues extend their side chains through the cytoplasm to exploit phospholipids as anchors for conformational switching. Thus, phospholipid-Arg/Lys and phospholipid-Trp interactions have distinct functional roles in the dynamics of ion pumps and, presumably, membrane proteins in general.


Assuntos
ATPases Transportadoras de Cálcio/química , ATPases Transportadoras de Cálcio/metabolismo , Cálcio/metabolismo , Fosfolipídeos/metabolismo , Arginina/metabolismo , Cristalização , Cristalografia por Raios X , Citoplasma/metabolismo , Bicamadas Lipídicas/química , Bicamadas Lipídicas/metabolismo , Lisina/metabolismo , Modelos Moleculares , Fosfolipídeos/química , Conformação Proteica , Triptofano/metabolismo
7.
Int J Mol Sci ; 24(9)2023 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-37175592

RESUMO

This article provides a synopsis of current progress made in fundamental studies of lower urinary tract dysfunction (LUTD) after spinal cord injury (SCI) above the sacral level. Animal models of SCI allowed us to examine the effects of SCI on the micturition control and the underlying neurophysiological processes of SCI-induced LUTD. Urine storage and elimination are the two primary functions of the LUT, which are governed by complicated regulatory mechanisms in the central and peripheral nervous systems. These neural systems control the action of two functional units in the LUT: the urinary bladder and an outlet consisting of the bladder neck, urethral sphincters, and pelvic-floor striated muscles. During the storage phase, the outlet is closed, and the bladder is inactive to maintain a low intravenous pressure and continence. In contrast, during the voiding phase, the outlet relaxes, and the bladder contracts to facilitate adequate urine flow and bladder emptying. SCI disrupts the normal reflex circuits that regulate co-ordinated bladder and urethral sphincter function, leading to involuntary and inefficient voiding. Following SCI, a spinal micturition reflex pathway develops to induce an overactive bladder condition following the initial areflexic phase. In addition, without proper bladder-urethral-sphincter coordination after SCI, the bladder is not emptied as effectively as in the normal condition. Previous studies using animal models of SCI have shown that hyperexcitability of C-fiber bladder afferent pathways is a fundamental pathophysiological mechanism, inducing neurogenic LUTD, especially detrusor overactivity during the storage phase. SCI also induces neurogenic LUTD during the voiding phase, known as detrusor sphincter dyssynergia, likely due to hyperexcitability of Aδ-fiber bladder afferent pathways rather than C-fiber afferents. The molecular mechanisms underlying SCI-induced LUTD are multifactorial; previous studies have identified significant changes in the expression of various molecules in the peripheral organs and afferent nerves projecting to the spinal cord, including growth factors, ion channels, receptors and neurotransmitters. These findings in animal models of SCI and neurogenic LUTD should increase our understanding of pathophysiological mechanisms of LUTD after SCI for the future development of novel therapies for SCI patients with LUTD.


Assuntos
Traumatismos da Medula Espinal , Bexiga Urinária Hiperativa , Animais , Bexiga Urinária/fisiologia , Micção/fisiologia , Traumatismos da Medula Espinal/complicações , Medula Espinal
8.
Biochem Biophys Res Commun ; 607: 54-59, 2022 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-35366544

RESUMO

Corticotropin-releasing factor (CRF), a representative stress-related neuropeptide, in the central nervous system reportedly both facilitates and suppresses the micturition, therefore, roles of central CRF in regulation of the micturition are still controversial. In this study, we investigated (1) effects of intracerebroventricularly (icv)-administered CRF on the micturition, and (2) brain CRF receptor subtypes (CRFR1/CRFR2) and glutamatergic receptors (NMDA/AMPA subtypes) involved in the CRF-induced effects in male Wistar rats under urethane anesthesia. Intercontraction intervals (ICI), and maximal voiding pressure (MVP), were evaluated by continuous cystometry 45 min before CRF administration or intracerebroventricular pretreatment with other drugs as follows and 3 h after CRF administration. Single-voided volume (Vv), post-voiding residual volume (Rv), bladder capacity (BC), and voiding efficiency (VE) were evaluated by single cystometry 60 min before CRF administration and 60-120 min after the administration. Icv-administered CRF reduced ICI, Vv, and BC without changing MVP, Rv, or VE. The CRF-induced ICI reduction was attenuated by icv-pretreated CP154526 (CRFR1 antagonist), MK-801 (NMDA receptor antagonist), and DNQX (AMPA receptor antagonist), but not by K41498 (CRFR2 antagonist). These results indicate that stimulation of brain CRFR1 can be involved in facilitation of the rat micturition via brain NMDA/AMPA receptors.


Assuntos
Receptores de Hormônio Liberador da Corticotropina , Micção , Animais , Encéfalo , Hormônio Liberador da Corticotropina/farmacologia , Masculino , N-Metilaspartato/farmacologia , Ratos , Ratos Wistar , Receptores de N-Metil-D-Aspartato
9.
Nitric Oxide ; 127: 54-63, 2022 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-35918055

RESUMO

Cyclophosphamide (CYP), a broad-spectrum anticancer drug, causes serious side effects, such as haemorrhagic cystitis (HC). Hydrogen sulfide (H2S), an endogenous gasotransmitter, has physiological properties, including anti-inflammation, anti-oxidation, and neuromodulation. In this study, we investigated the effects of NaHS (H2S donor) pretreatment on bladder dysfunction in CYP-treated rats. Male Wistar rats were intraperitoneally pretreated with NaHS (3 or 10 µmol/kg) or vehicle once daily for 7 days before cystometry, and CYP (150 mg/kg) or saline was intraperitoneally administered 2 days before cystometry. After cystometry, the bladder tissues were collected for haematoxylin and eosin staining. In some rats, capsaicin (CAP), which can desensitise CAP-sensitive afferent nerves, was subcutaneously injected at 125 mg/kg 4 days before cystometry. CYP reduced intercontraction intervals (ICI) and bladder compliance (Comp) and increased the number of non-voiding contractions (NVCs) compared with the saline-treated control group. NaHS pretreatment dose-dependently improved the CYP-induced these changes. In bladder tissues, CYP increased histological scores of neutrophil infiltration, haemorrhage, and oedema, while NaHS had no effect on these CYP-induced changes. CAP showed a tendency to suppress CYP-induced changes in ICI. NaHS-induced improvement in CYP-induced changes in urodynamic parameters were not detected in CAP-treated rats. These findings suggest that NaHS pretreatment prevented bladder dysfunction in CYP-treated rats by suppressing CAP-sensitive bladder afferent nerves, but not by suppressing bladder inflammation. Therefore, H2S represents a new candidate as a protective drug for bladder dysfunction induced by HC, a side effect of CYP chemotherapy.


Assuntos
Cistite , Sulfeto de Hidrogênio , Animais , Ciclofosfamida/efeitos adversos , Cistite/induzido quimicamente , Cistite/tratamento farmacológico , Cistite/prevenção & controle , Sulfeto de Hidrogênio/farmacologia , Sulfeto de Hidrogênio/uso terapêutico , Masculino , Ratos , Ratos Wistar , Bexiga Urinária
10.
Anticancer Drugs ; 33(1): e818-e821, 2022 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-34486537

RESUMO

Recently, combination therapy including immune checkpoint inhibition (ICI) has proven to be effective as first-line therapy for patients with metastatic renal cell carcinoma. Although the first-line combination therapies with ICI have shown clinical benefit, a number of patients require second-line treatment. We report a 60-year-old man with metastatic renal cell carcinoma who was treated with pazopanib soon after nivolumab plus ipilimumab combination therapy. He experienced Grade 3 disseminated intravascular coagulation (DIC). We suspect that this was caused by an interaction between pazopanib and nivolumab even though ICI therapy was discontinued. He was treated with thrombomodulin and platelet transfusion and recovered from DIC. Treatment with pazopanib was subsequently restarted. No evidence of DIC was observed thereafter. This severe adverse reaction may have been induced by an interaction between activated proinflammatory immune cells and cytokines from an exacerbated inflammatory state and pazopanib. This report highlights the need to perform careful monitoring of patients who receive molecular targeted therapy after ICI-based immunotherapy.


Assuntos
Antineoplásicos Imunológicos/uso terapêutico , Carcinoma de Células Renais/tratamento farmacológico , Coagulação Intravascular Disseminada/induzido quimicamente , Indazóis/efeitos adversos , Neoplasias Renais/tratamento farmacológico , Nivolumabe/uso terapêutico , Pirimidinas/efeitos adversos , Sulfonamidas/efeitos adversos , Antineoplásicos Imunológicos/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma de Células Renais/patologia , Humanos , Inibidores de Checkpoint Imunológico/uso terapêutico , Indazóis/uso terapêutico , Ipilimumab/uso terapêutico , Neoplasias Renais/patologia , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Nivolumabe/administração & dosagem , Pirimidinas/uso terapêutico , Sulfonamidas/uso terapêutico
11.
J Biol Chem ; 295(43): 14630-14639, 2020 10 23.
Artigo em Inglês | MEDLINE | ID: mdl-32820047

RESUMO

General control nonderepressible 5 (GCN5, also known as Kat2a) and p300/CBP-associated factor (PCAF, also known as Kat2b) are two homologous acetyltransferases. Both proteins share similar domain architecture consisting of a PCAF N-terminal (PCAF_N) domain, acetyltransferase domain, and a bromodomain. PCAF also acts as a ubiquitin E3 ligase whose activity is attributable to the PCAF_N domain, but its structural aspects are largely unknown. Here, we demonstrated that GCN5 exhibited ubiquitination activity in a similar manner to PCAF and its activity was supported by the ubiquitin-conjugating enzyme UbcH5. Moreover, we determined the crystal structure of the PCAF_N domain at 1.8 Å resolution and found that PCAF_N domain folds into a helical structure with a characteristic binuclear zinc region, which was not predicted from sequence analyses. The zinc region is distinct from known E3 ligase structures, suggesting this region may form a new class of E3 ligase. Our biochemical and structural study provides new insight into not only the functional significance of GCN5 but also into ubiquitin biology.


Assuntos
Ubiquitina-Proteína Ligases/química , Fatores de Transcrição de p300-CBP/química , Animais , Cristalografia por Raios X , Humanos , Camundongos , Modelos Moleculares , Conformação Proteica , Domínios Proteicos , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitinação , Fatores de Transcrição de p300-CBP/metabolismo
12.
J Am Chem Soc ; 143(15): 5845-5854, 2021 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-33755463

RESUMO

Helical folding of randomly coiled linear polymers is an essential organization process not only for biological polypeptides but also for synthetic functional polymers. Realization of this dynamic process in supramolecular polymers (SPs) is, however, a formidable challenge because of their inherent lability of main chains upon changing an external environment that can drive the folding process (e.g., solvent, concentration, and temperature). We herein report a photoinduced reversible folding/unfolding of rosette-based SPs driven by photoisomerization of a diarylethene (DAE). Temperature-controlled supramolecular polymerization of a barbiturate-functionalized DAE (open isomer) in nonpolar solvent results in the formation of intrinsically curved, but randomly coiled, SPs due to the presence of defects. Irradiation of the randomly coiled SPs with UV light causes efficient ring-closure reaction of the DAE moieties, which induces helical folding of the randomly coiled structures into helicoidal ones, as evidenced by atomic force microscopy and small-angle X-ray scattering. The helical folding is driven by internal structure ordering of the SP fiber that repairs the defects and interloop interaction occurring only for the resulting helicoidal structure. In contrast, direct supramolecular polymerization of the ring-closed DAE monomers by temperature control affords linearly extended ribbon-like SPs lacking intrinsic curvature that are thermodynamically less stable compared to the helicoidal SPs. The finding represents an important concept applicable to other SP systems; that is, postpolymerization (photo)reaction of preorganized kinetic structures can lead to more thermodynamically stable structures that are inaccessible directly through temperature-controlled protocols.


Assuntos
Etilenos/química , Polímeros/química , Raios Ultravioleta , Barbitúricos/química , Isomerismo , Substâncias Macromoleculares/química , Microscopia de Força Atômica , Polimerização , Temperatura , Termodinâmica
13.
Prostate ; 81(16): 1287-1293, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34516694

RESUMO

BACKGROUND: The pathophysiology of the prostate enlargement underlying lower urinary tract symptoms is unknown. Meanwhile, the gut microbiota can contribute to various host conditions. We hypothesized that the gut microbiota plays a role in prostate enlargement. METHODS: We included 128 patients who underwent prostate biopsies at our hospitals between December 2018 and March 2020, excluding those who had used antibiotics within the past 6 months and those who were diagnosed with prostate cancer of cT3 or higher. Patients with prostate volumes ≥30 ml were defined as the prostate-enlargement (PE) group; those with prostate volumes <30 ml were defined as the non-PE group. Their gut microbiotas were analyzed via 16S rRNA metagenomic analyses of rectal swab samples and were compared between the groups. RESULTS: The PE group included 66 patients; the non-PE group included 62 patients. Age, body mass index, and prostate-specific antigen levels did not significantly differ between the groups. Linear discriminant analysis effect size analysis indicated a higher proportion of Firmicutes and Actinobacteria in the PE group and a higher proportion of Bacteroidetes in the non-PE group. The Firmicutes/Bacteroidetes (F/B) ratio was significantly higher in the PE group than in the non-PE group (2.21 ± 0.39 vs. 1.61 ± 0.40, p = 0.015). CONCLUSION: The F/B ratio of the gut microbiota was associated with prostate enlargement. Although the detailed mechanisms are unclear, the gut microbiota might affect prostate enlargement.


Assuntos
Bacteroidetes/isolamento & purificação , Firmicutes/isolamento & purificação , Microbioma Gastrointestinal/fisiologia , Próstata/patologia , Hiperplasia Prostática , Neoplasias da Próstata , Biópsia/métodos , Biópsia/estatística & dados numéricos , Humanos , Masculino , Metagenômica/métodos , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Tamanho do Órgão , Hiperplasia Prostática/diagnóstico , Hiperplasia Prostática/microbiologia , Neoplasias da Próstata/microbiologia , Neoplasias da Próstata/patologia , Neoplasias da Próstata/fisiopatologia , RNA Ribossômico 16S/isolamento & purificação , Fatores de Risco
14.
J Virol ; 94(17)2020 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-32581091

RESUMO

Measles virus (MeV) is a highly immunotropic and contagious pathogen that can even diminish preexisting antibodies and remains a major cause of childhood morbidity and mortality worldwide despite the availability of effective vaccines. MeV is one of the most extensively studied viruses with respect to the mechanisms of JAK-STAT antagonism. Of the three proteins translated from the MeV P gene, P and V are essential for inactivation of this pathway. However, the lack of data from direct analyses of the underlying interactions means that the detailed molecular mechanism of antagonism remains unresolved. Here, we prepared recombinant MeV V protein, which is responsible for human JAK-STAT antagonism, and a panel of variants, enabling the biophysical characterization of V protein, including direct V/STAT1 and V/STAT2 interaction assays. Unambiguous direct interactions between the host and viral factors, in the absence of other factors such as Jak1 or Tyk2, were observed, and the dissociation constants were quantified for the first time. Our data indicate that interactions between the C-terminal region of V and STAT2 is 1 order of magnitude stronger than that of the N-terminal region of V and STAT1. We also clarified that these interactions are completely independent of each other. Moreover, results of size exclusion chromatography demonstrated that addition of MeV-V displaces STAT2-core, a rigid region of STAT2 lacking the N- and C-terminal domains, from preformed complexes of STAT2-core/IRF-associated domain (IRF9). These results provide a novel model whereby MeV-V can not only inhibit the STAT2/IRF9 interaction but also disrupt preassembled interferon-stimulated gene factor 3.IMPORTANCE To evade host immunity, many pathogenic viruses inactivate host Janus kinase signal transducer and activator of transcription (STAT) signaling pathways using diverse strategies. Measles virus utilizes P and V proteins to counteract this signaling pathway. Data derived largely from cell-based assays have indicated several amino acid residues of P and V proteins as important. However, biophysical properties of V protein or its direct interaction with STAT molecules using purified proteins have not been studied. We have developed novel molecular tools enabling us to identify a novel molecular mechanism for immune evasion whereby V protein disrupts critical immune complexes, providing a clear strategy by which measles virus can suppress interferon-mediated antiviral gene expression.


Assuntos
Fator Gênico 3 Estimulado por Interferon, Subunidade gama/química , Vírus do Sarampo/metabolismo , Fosfoproteínas/química , Fator de Transcrição STAT2/química , Proteínas Virais/química , Sítios de Ligação , Expressão Gênica , Humanos , Evasão da Resposta Imune , Imunidade Inata , Fator Gênico 3 Estimulado por Interferon, Subunidade gama/genética , Fator Gênico 3 Estimulado por Interferon, Subunidade gama/metabolismo , Janus Quinases/metabolismo , Vírus do Sarampo/genética , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , Ligação Proteica , Domínios Proteicos , Domínios e Motivos de Interação entre Proteínas , Fator de Transcrição STAT1/química , Fator de Transcrição STAT1/genética , Fator de Transcrição STAT1/metabolismo , Fator de Transcrição STAT2/genética , Fator de Transcrição STAT2/metabolismo , Transdução de Sinais , Proteínas Virais/genética , Proteínas Virais/metabolismo , Dedos de Zinco
15.
Neurourol Urodyn ; 40(6): 1460-1469, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34015154

RESUMO

AIMS: Spinal cord injury (SCI) above the sacral level causes bladder dysfunction and remodeling with fibrosis. This study examined the antifibrotic effects using nintedanib, an inhibitor of vascular endothelial growth factor, fibroblast growth factor, and platelet-derived growth factor receptors, on detrusor overactivity (DO) and bladder fibrosis, as well as the modulation mechanisms of C-fiber afferent pathways. METHODS: Thirty female C57BL/6 mice were divided into group A (spinal intact), group B (SCI with vehicle), and group C (SCI with nintedanib). At 2 weeks after SCI, vehicle or 50 mg/kg nintedanib was administered subcutaneously for 2 weeks. Then, cystometry was conducted, followed by RT-PCR measurements of fibrosis-related molecules, muscarinic, ß-adrenergic, TRP and purinergic receptors in the bladder or L6-S1 dorsal root ganglia (DRG). Trichrome stain and Western blot analysis of transforming growth factor-beta and fibronectin were performed in the bladder. TRPV1 expression in L6 DRG was measured by immunohistochemistry. RESULTS: In cystometry, intercontraction intervals, nonvoiding contractions, voided volume, and voiding efficiency were significantly improved in group C versus group B. RT-PCR, Western blotting, and trichrome staining revealed the fibrotic changes in the bladder of group B, which was improved in group C. Increased messenger RNA levels of TRPV1, TRPA1, P2X2 , and P2X3 in DRG of group B were significantly decreased in group C. TRPV1 immunoreactivity in DRG was increased in group B, but decreased in group C. CONCLUSIONS: Nintedanib improves storage and voiding dysfunctions and bladder fibrosis in SCI mice. Also, nintedanib-induced improvement of DO is associated with reduced expression of C-fiber afferent markers, suggesting the modulation of bladder C-fiber afferent activity.


Assuntos
Traumatismos da Medula Espinal , Bexiga Urinária , Animais , Feminino , Fatores de Crescimento de Fibroblastos , Camundongos , Camundongos Endogâmicos C57BL , Receptores do Fator de Crescimento Derivado de Plaquetas , Traumatismos da Medula Espinal/complicações , Traumatismos da Medula Espinal/tratamento farmacológico , Fator A de Crescimento do Endotélio Vascular
16.
Nucleic Acids Res ; 47(20): 10942-10955, 2019 11 18.
Artigo em Inglês | MEDLINE | ID: mdl-31586407

RESUMO

The complex between Trm7 and Trm734 (Trm7-Trm734) from Saccharomyces cerevisiae catalyzes 2'-O-methylation at position 34 in tRNA. We report biochemical and structural studies of the Trm7-Trm734 complex. Purified recombinant Trm7-Trm734 preferentially methylates tRNAPhe transcript variants possessing two of three factors (Cm32, m1G37 and pyrimidine34). Therefore, tRNAPhe, tRNATrp and tRNALeu are specifically methylated by Trm7-Trm734. We have solved the crystal structures of the apo and S-adenosyl-L-methionine bound forms of Trm7-Trm734. Small angle X-ray scattering reveals that Trm7-Trm734 exists as a hetero-dimer in solution. Trm7 possesses a Rossmann-fold catalytic domain, while Trm734 consists of three WD40 ß-propeller domains (termed BPA, BPB and BPC). BPA and BPC form a unique V-shaped cleft, which docks to Trm7. The C-terminal region of Trm7 is required for binding to Trm734. The D-arm of substrate tRNA is required for methylation by Trm7-Trm734. If the D-arm in tRNAPhe is docked onto the positively charged area of BPB in Trm734, the anticodon-loop is located near the catalytic pocket of Trm7. This model suggests that Trm734 is required for correct positioning of tRNA for methylation. Additionally, a point-mutation in Trm7, which is observed in FTSJ1 (human Trm7 ortholog) of nosyndromic X-linked intellectual disability patients, decreases the methylation activity.


Assuntos
RNA de Transferência/metabolismo , Proteínas de Saccharomyces cerevisiae/química , Saccharomyces cerevisiae/enzimologia , Proteínas de Transporte Vesicular/química , tRNA Metiltransferases/química , Domínio Catalítico , Ligação de Hidrogênio , Metilação , Modelos Moleculares , Proteínas Mutantes/química , Proteínas Mutantes/metabolismo , Ligação Proteica , Subunidades Proteicas/química , Pirimidinas/metabolismo , Proteínas Recombinantes/metabolismo , S-Adenosilmetionina/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Especificidade por Substrato , Proteínas de Transporte Vesicular/metabolismo , tRNA Metiltransferases/metabolismo
17.
Int J Urol ; 28(10): 1068-1072, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34272910

RESUMO

OBJECTIVES: To investigate the effect of vibegron, a new clinically approved ß3-adrenoceptor agonist in lower urinary tract dysfunction in mice with spinal cord injury. METHODS: Investigators performed cystometry under awake conditions in 4-week spinal cord injury female mice. Two weeks after spinal cord injury, saline or vibegron (30 mg/kg) was orally administered for 2 weeks prior to the urodynamic study. Investigators removed L6-S1 dorsal root ganglia from the saline- or vibegron-treated spinal cord injury mice as well as from saline-treated normal (spinal intact) mice to evaluate the levels of transient receptor potential cation channel subfamily V member 1, transient receptor potential cation channel subfamily A member 1, activating transcription factor 3, and inducible nitric oxide synthase transcripts using real-time polymerase chain reaction. RESULTS: In vibegron-treated spinal cord injury mice, nonvoiding contractions during bladder filling, which were increased in spinal cord injury compared to spinal intact mice, were significantly decreased. Micturition pressure or voiding efficiency was not significantly increased in comparison to measurements in saline-treated spinal cord injury mice. The expression of transient receptor potential cation channel subfamily V member 1, transient receptor potential cation channel subfamily A member 1, activating transcription factor 3, and inducible nitric oxide synthase messenger RNA was increased in spinal cord injury mice compared to spinal intact mice, but significantly decreased after vibegron treatment. CONCLUSIONS: Vibegron improves spinal cord injury-induced detrusor overactivity in addition to significantly reducing C-fiber afferent receptors such as transient receptor potential cation channel subfamily V member 1, transient receptor potential cation channel subfamily A member 1, and inflammatory cytokines/markers, such as activating transcription factor 3 and inducible nitric oxide synthase, in spinal cord injury mice. Thus, vibegron might be effective in the treatment of storage lower urinary tract dysfunction induced by C-fiber afferent activation after spinal cord injury.


Assuntos
Traumatismos da Medula Espinal , Bexiga Urinária , Agonistas de Receptores Adrenérgicos beta 3/farmacologia , Agonistas de Receptores Adrenérgicos beta 3/uso terapêutico , Animais , Feminino , Camundongos , Pirimidinonas , Pirrolidinas , Medula Espinal , Traumatismos da Medula Espinal/complicações , Traumatismos da Medula Espinal/tratamento farmacológico , Urodinâmica
18.
Hinyokika Kiyo ; 67(2): 63-66, 2021 Feb.
Artigo em Japonês | MEDLINE | ID: mdl-33657773

RESUMO

A 67-year-old man underwent open radical left nephrectomy for left renal cell carcinoma [pT4N0M1 (right lower lobe of lung)] and thoracoscopic partial right lung resection for lung metastasis. The patient subsequently developed a solitary lung metastasis at 10 months and then at 26 months postoperatively. He underwent partial lung resection on each occasion. During the 28 months postoperatively, he was found to have a 12 mm middle mediastinal lymph node metastasis and a 30 mm splenic metastasis, which gradually increased in size. Three months after discovery, sunitinib was initiated at 37.5 mg 2 weeks on/1 week off. Twelve days later, the patient presented with complaints of fever. A gas-producing splenic abscess was diagnosed and he was admitted on the same day. His condition improved with antibiotics and splenic drainage. On day 35 of hospitalization, he underwent laparoscopic splenectomy. The patient's postoperative clinical course was uneventful and he was discharged 7 days after the surgery.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Esplenopatias , Neoplasias Esplênicas , Abscesso/diagnóstico por imagem , Abscesso/tratamento farmacológico , Abscesso/etiologia , Idoso , Carcinoma de Células Renais/tratamento farmacológico , Carcinoma de Células Renais/cirurgia , Humanos , Neoplasias Renais/tratamento farmacológico , Neoplasias Renais/cirurgia , Masculino , Neoplasias Esplênicas/diagnóstico por imagem , Neoplasias Esplênicas/tratamento farmacológico , Neoplasias Esplênicas/cirurgia , Sunitinibe/uso terapêutico
19.
Angew Chem Int Ed Engl ; 60(52): 26986-26993, 2021 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-34623014

RESUMO

Synthesis of one-dimensional nanofibers with distinct topological (higher-order structural) domains in the same main chain is one of the challenging topics in modern supramolecular polymer chemistry. Non-uniform structural transformation of supramolecular polymer chains by external stimuli may enable preparation of such nanofibers. To demonstrate feasibility of this post-polymerization strategy, we prepared a photoresponsive helically folded supramolecular polymers from a barbiturate monomer containing an azobenzene-embedded rigid π-conjugated scaffold. In contrast to previous helically folded supramolecular polymers composed of a more flexible azobenzene monomer, UV-light induced unfolding of the newly prepared helically folded supramolecular polymers occurred nonuniformly, affording topological block copolymers consisting of folded and unfolded domains. The formation of such blocky copolymers indicates that the photoinduced unfolding of the helically folded structures initiates from relatively flexible parts such as termini or defects. Spontaneous refolding of the unfolded domains was observed after visible-light irradiation followed by aging to restore fully folded structures.

20.
Neurourol Urodyn ; 39(5): 1550-1556, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32460398

RESUMO

AIMS: There is accumulating evidence that excessive salt intake contributes to nocturnal polyuria. We aimed to investigate the relationship between salt intake, leg edema, and nocturnal urine volume (NUV) to assess the etiology of nocturnal polyuria. METHODS: A total of 56 men aged ≥60 years who were hospitalized for benign prostatic hyperplasia or with suspected prostatic cancer were enrolled. Urine frequency-volume charts of the patients were maintained, and they underwent bioelectrical impedance analysis twice daily (at 5:00 pm and 6:00 am) and examination of blood (brain natriuretic peptide levels) and urine (sodium and creatinine levels and osmotic pressure) samples once daily (at 6:00 am). Free-water clearance, solute clearance, and sodium clearance at night were measured, and daily salt intake was estimated. RESULTS: The data of 52 patients were analyzed. Daily salt intake positively correlated with leg edema at 5:00 pm, differences in leg extracellular fluid levels between 5:00 pm and 6:00 am, and NUV, but not with diurnal urine volume. Partial correlation coefficients showed that salt intake was a factor of the correlation between NUV and change in extracellular volume in the legs between 5:00 pm and 6:00 am. A multivariate logistic model showed that sleep duration and sodium clearance were independent predictive factors for nocturnal polyuria. CONCLUSIONS: Sodium intake correlates with diurnal leg edema and NUV in elderly men. These results provide evidence supporting sodium restriction as an effective treatment for nocturnal polyuria.


Assuntos
Edema/etiologia , Noctúria/etiologia , Poliúria/etiologia , Cloreto de Sódio na Dieta/efeitos adversos , Idoso , Humanos , Perna (Membro) , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
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