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1.
Ann Anat ; 253: 152228, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38340878

RESUMEN

BACKGROUND: The first extensor compartment of the wrist is known as a frequent site of stenosing tenosynovitis, referred to as de Quervain's disease. De Quervain's disease occurs more frequently in the dorsal part of the first extensor compartment than in the palmar part; however, the anatomical reason why the dorsal part is worse remains poorly elucidated. This study clarified the morphological differences between the dorsal and palmar parts by examining their relationship with the surrounding structures. METHODS: In this study, a total of 35 wrists from 23 Japanese cadavers were used. Twenty-five wrists were randomly assigned for macroscopic analysis, and the remaining 10 wrists were used for histological analysis. RESULTS: The palmar septum of the first extensor compartment was connected to the brachioradialis tendon and superficial head of the pronator quadratus and was histologically stout compared to the dorsal septum. Despite several anatomical variations, such as the septum between the abductor pollicis longus/extensor pollicis brevis and the multiple tendons of these muscles, the aforementioned characteristics of the fibrous sheath in the first extensor compartment were identical in all specimens. CONCLUSION: In contrast to the fragile structure of the dorsal septum, the stout structure of the palmar septum could be related to the low occurrence of symptoms of de Quervain's disease. The present results could play a role in revealing the pathogeny and establish the precise treatment for de Quervain's disease and provide an anatomical basis for kinesiological/biomechanical studies.


Asunto(s)
Enfermedad de De Quervain , Humanos , Enfermedad de De Quervain/patología , Músculo Esquelético/patología , Tendones/anatomía & histología , Antebrazo , Mano/patología
2.
Viruses ; 14(11)2022 11 08.
Artículo en Inglés | MEDLINE | ID: mdl-36366568

RESUMEN

Hepatitis B virus (HBV) specifically infects human hepatocytes and increases the risks of cirrhosis and liver cancer. Currently, nucleic acid analogs are the main therapeutics for chronic hepatitis caused by HBV infection. Although nucleic acid analogs can eliminate HBV DNA by inhibiting HBV reverse transcriptase, they cannot lead to negative conversion of covalently closed circular DNA (cccDNA) and hepatitis B surface antigen (HBsAg). In this study, we revealed that the antifilarial drug ivermectin suppresses HBV production by a different mechanism from the nucleic acid analog entecavir or Na+ taurocholate co-transporting polypeptide-mediated entry inhibitor cyclosporin A. Ivermectin reduced the levels of several HBV markers, including HBsAg, in HBV-infected human hepatocellular carcinoma cells (HepG2-hNTCP-C4 cells) and humanized mouse hepatocytes (PXB hepatocytes). In addition, ivermectin significantly decreased the expression of HBV core protein and the nuclear transporter karyopherin α2 (KPNA2) in the nuclei of HepG2-hNTCP-C4 cells. Furthermore, depletion of KPNA1-6 suppressed the production of cccDNA. These results suggest that KPNA1-6 is involved in the nuclear import of HBV and that ivermectin suppresses the nuclear import of HBV by inhibiting KPNA2. This study demonstrates the potential of ivermectin as a novel treatment for hepatitis B.


Asunto(s)
Hepatitis B Crónica , Hepatitis B , Ratones , Animales , Humanos , Virus de la Hepatitis B/genética , Antígenos de Superficie de la Hepatitis B/metabolismo , Ivermectina/farmacología , ADN Circular/metabolismo , ADN Viral/metabolismo , Replicación Viral/genética , alfa Carioferinas/metabolismo
3.
Cancers (Basel) ; 13(22)2021 Nov 12.
Artículo en Inglés | MEDLINE | ID: mdl-34830830

RESUMEN

(1) Background: multiple myeloma patients have benefited from bortezomib therapy, though it has often been discontinued owing to diarrhea. The objective of this study was to verify serum bortezomib concentration in the emergence of diarrhea. (2) Methods: this prospective, observational case-control, and monocentric study was performed with an approval by the Ethics Committee of Kumamoto University Hospital in 2015 (No. 1121) from February 2015 to April 2017. (3) Results: twenty-four patients with bortezomib therapy were recruited; eight patients (33.3%) developed diarrhea at day 3 as median. Median measured trough bortezomib concentration at 24 h after first or second dose for patients with or without diarrhea was 0.87 or 0.48 ng/mL, respectively (p = 0.04, Wilcoxon signed rank test). Receiver operation characteristic (ROC) analysis produced the cut-off concentration of 0.857 ng/mL (area under the ROC curve of 0.797, sensitivity of 0.625, specificity of 0.875). The survival curves between patients with and without diarrhea were similar (p = 0.667); those between patients with higher and lower concentration than median value (0.61 ng/mL) were also similar (p = 0.940). (4) Conclusions: this study indicated the possible involvement of serum bortezomib concentration in the emergence of diarrhea in bortezomib therapy in patients with multiple myeloma.

4.
Plant J ; 105(6): 1507-1520, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33300204

RESUMEN

Legumes and nitrogen-fixing rhizobial bacteria establish root nodule symbiosis, which is orchestrated by several plant hormones. Exogenous addition of biologically active gibberellic acid (GA) is known to inhibit root nodule symbiosis. However, the precise role of GA has not been elucidated because of the trace amounts of these hormones in plants and the multiple functions of GAs. Here, we found that GA signaling acts as a key regulator in a long-distance negative-feedback system of root nodule symbiosis called autoregulation of nodulation (AON). GA biosynthesis is activated during nodule formation in and around the nodule vascular bundles, and bioactive GAs accumulate in the nodule. In addition, GA signaling induces expression of the symbiotic transcription factor NODULE INCEPTION (NIN) via a cis-acting region on the NIN promoter. Mutants with deletions of this cis-acting region have increased susceptibility to rhizobial infection and reduced GA-induced CLE-RS1 and CLE-RS2 expression, suggesting that the inhibitory effect of GAs occurs through AON. This is supported by the GA-insensitive phenotypes of an AON-defective mutant of HYPERNODULATION ABERRANT ROOT FORMATION1 (HAR1) and a reciprocal grafting experiment. Thus, endogenous GAs induce NIN expression via its GA-responsive cis-acting region, and subsequently the GA-induced NIN activates the AON system to regulate nodule formation.


Asunto(s)
Giberelinas/farmacología , Lotus/efectos de los fármacos , Proteínas de Plantas/metabolismo , Nódulos de las Raíces de las Plantas/efectos de los fármacos , Simbiosis/efectos de los fármacos , Factores de Transcripción/metabolismo , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Lotus/metabolismo , Lotus/fisiología , Proteínas de Plantas/fisiología , Nodulación de la Raíz de la Planta/efectos de los fármacos , Regiones Promotoras Genéticas/efectos de los fármacos , Nódulos de las Raíces de las Plantas/metabolismo , Nódulos de las Raíces de las Plantas/fisiología , Factores de Transcripción/fisiología
5.
Anal Biochem ; 599: 113748, 2020 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-32333903

RESUMEN

We applied an inducible gene expression system that utilizes the p-cmt operon, the cumate gene-switch, to generate mouse induced pluripotent stem (iPS) cells. Mouse embryonic fibroblast (MEF) E6E7-MEF cells were transfected with a single cumate gene-switch vector enabling concomitant expression of Oct4, Sox2, c-Myc, Klf4, and Gfp. Then, the cells were cultured with cumate, a monoterpene. An increase in colonies positive for alkaline phosphatase activity was observed dose-dependently with cumate. In the absence of cumate, the expression of GFP, a marker for transgene expression, was undetectable in tightly aggregated iPS cell-like colonies with endogenous expression of NANOG and OCT4. From primary MEFs using the cumate gene-switch, we also isolated iPS cells expressing endogenous NANOG, OCT4, SOX2, KLF4, and SSEA1 with hypo-methylated genomic promoter regions of endogenous Nanog and Oct4. In embryoid bodies with the progression of differentiation, expression of markers for all three germ layers was detected, and contracting cardiomyocytes were observed. Overall, we suggest that the cumate gene-switch is applicable for the generation of mouse iPS cells. The cumate gene-switch in combination with other inducible systems, such as the tet system, may provide useful approaches for analyzing the roles of transgenes underlying the establishment of iPS cells.


Asunto(s)
Benzoatos/farmacología , Vectores Genéticos , Células Madre Pluripotentes Inducidas , Transgenes , Animales , Diferenciación Celular , Línea Celular , Factor 4 Similar a Kruppel , Ratones
6.
Int J Mol Sci ; 20(20)2019 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-31635163

RESUMEN

Cisplatin is one of the most effective chemotherapeutic agents commonly used for several malignancies including oral squamous cell carcinoma (OSCC). Although cisplatin resistance is a major obstacle to effective treatment and is associated with poor prognosis of OSCC patients, the molecular mechanisms by which it develops are largely unknown. Cylindromatosis (CYLD), a deubiquitinating enzyme, acts as a tumor suppressor in several malignancies. Our previous studies have shown that loss of CYLD expression in OSCC tissues is significantly associated with poor prognosis of OSCC patients. Here, we focused on CYLD expression in OSCC cells and determined whether loss of CYLD expression is involved in cisplatin resistance in OSCC and elucidated its molecular mechanism. In this study, to assess the effect of CYLD down-regulation on cisplatin resistance in human OSCC cell lines (SAS), we knocked-down the CYLD expression by using CYLD-specific siRNA. In cisplatin treatment, cell survival rates in CYLD knockdown SAS cells were significantly increased, indicating that CYLD down-regulation caused cisplatin resistance to SAS cells. Our results suggested that cisplatin resistance caused by CYLD down-regulation was associated with the mechanism through which both the reduction of intracellular cisplatin accumulation and the suppression of cisplatin-induced apoptosis via the NF-κB hyperactivation. Moreover, the combination of cisplatin and bortezomib treatment exhibited significant anti-tumor effects on cisplatin resistance caused by CYLD down-regulation in SAS cells. These findings suggest the possibility that loss of CYLD expression may cause cisplatin resistance in OSCC patients through NF-κB hyperactivation and may be associated with poor prognosis in OSCC patients.


Asunto(s)
Antineoplásicos/farmacología , Carcinoma de Células Escamosas/patología , Cisplatino/farmacología , Enzima Desubiquitinante CYLD/metabolismo , Resistencia a Antineoplásicos , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Neoplasias de la Boca/patología , Apoptosis , Carcinoma de Células Escamosas/tratamiento farmacológico , Carcinoma de Células Escamosas/metabolismo , Proliferación Celular , Enzima Desubiquitinante CYLD/antagonistas & inhibidores , Enzima Desubiquitinante CYLD/genética , Humanos , Neoplasias de la Boca/tratamiento farmacológico , Neoplasias de la Boca/metabolismo , FN-kappa B/genética , FN-kappa B/metabolismo , Interferencia de ARN , Células Tumorales Cultivadas
7.
Medicine (Baltimore) ; 97(37): e12341, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30212986

RESUMEN

RATIONALE: Gastric adenocarcinoma of fundic gland type (GA-FG) is a new histological type of gastric cancer manifesting with differentiation into a fundic gland. Furthermore, gastric adenocarcinoma of fundic gland mucosa type (GA-FGM) is a tumor that shows differentiation into not only a fundic gland but also foveolar epithelium and a mucous gland. These tumors tend to invade the submucosal layer. However, no cases of these tumors being localized only in the submucosa have been reported. Here, we present a case of GA-FGM localized in the submucosa and describe the cytological features of this tumor. To our knowledge, this is the first reported case of GA-FGM localized in the submucosa. PATIENT CONCERNS: A man in his early 70s was referred to our institution because of the detection of a gastric submucosal tumor during a health checkup. DIAGNOSES: Gastric adenocarcinoma of fundic gland mucosa type. INTERVENTIONS: Endoscopic ultrasound-guided fine-needle aspiration (FNA), endoscopic submucosal dissection (ESD), and total gastrectomy with lymph node dissection were performed. OUTCOMES: The FNA specimen showed epithelial cells with low-grade atypia. In the ESD specimen, adenocarcinoma showing a gastric fundic gland mucosa-like morphology was observed. Immunohistochemical analysis showed positive staining for pepsinogen I, H+/K+-adenosine triphosphatase, MUC6, and MUC5AC and negative staining for MUC2 and CD10, indicating tumor differentiation into fundic gland mucosa. Therefore, the tumor was diagnosed as GA-FGM, with localization in the submucosal layer. Total gastrectomy and lymph node dissection were performed because of the positive margins of the ESD specimen. Neither residual tumor nor lymph node metastasis was detected; however, many foci of heterotopic gastric glands (HGGs) were observed in the gastric wall, suggesting that GA-FGM arose from an HGG. After treatment, no recurrence was observed during a 1-year follow-up period. LESSONS: Various tumors may arise from HGGs. Furthermore, when an FNA specimen shows gastric fundic gland mucosa-like epithelial cells with weak atypia, the possibility of GA-FG and GA-FGM should be considered.


Asunto(s)
Adenocarcinoma/patología , Neoplasias Gástricas/patología , Anciano , Fundus Gástrico/patología , Mucosa Gástrica/patología , Humanos , Masculino
8.
Neurosci Lett ; 570: 1-4, 2014 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-24746930

RESUMEN

This study examined the effects of exposure to low concentrations (0.1-100 nM) of bisphenol A (BPA) or nonylphenol (NP) on neuronal differentiation in pheochromocytoma PC12 cells. Pre-exposure to BPA for a week or a month, but not for a day, decreased neuronal differentiation in PC12 cells. Likewise, one week's pre-exposure to NP also inhibited neuronal differentiation in these cells. The inhibitory effects were still observed when PC12 cells were treated with BPA or NP for a week, followed by a week's withdrawal. These findings suggest that long-term exposure of PC12 cells to low concentrations of BPA or NP leads to changes in the cellular machinery responsible for neuronal differentiation, and these changes might be retained within PC12 cells.


Asunto(s)
Disruptores Endocrinos/toxicidad , Neuronas/efectos de los fármacos , Animales , Compuestos de Bencidrilo/toxicidad , Muerte Celular/efectos de los fármacos , Diferenciación Celular , Receptor alfa de Estrógeno/genética , Receptor alfa de Estrógeno/metabolismo , Receptor beta de Estrógeno/genética , Receptor beta de Estrógeno/metabolismo , Neuronas/citología , Neuronas/metabolismo , Estrés Oxidativo/efectos de los fármacos , Células PC12 , Fenoles/toxicidad , Feocromocitoma , Ratas , Receptores de Estrógenos/genética , Receptores de Estrógenos/metabolismo , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo
9.
Cell Biol Int ; 38(7): 868-74, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24604882

RESUMEN

When Swiss 3T3 fibroblasts were exposed to bisphenol A (BPA) or nonylphenol (NP) within a range of 0.1-100 nM for 30-45 days, increased resistance to oxidative injury was found. Western blot analysis indicated concomitant increased expression of bcl-2 protein and reduced histone methylation levels in cells after BPA or NP exposure. Using a heterologous expression system, both chemicals could stimulate G protein-coupled receptor 30 (GPR30), a transmembrane estrogen receptor predominantly expressed in 3T3 cells, at lower concentrations, which gave increased survival. Taken together, these results suggest that BPA or NP exposure might cause alterations in cellular activity against oxidative stress, possibly through GPR30.


Asunto(s)
Disruptores Endocrinos/toxicidad , Estrés Oxidativo/efectos de los fármacos , Células 3T3 , Animales , Apoptosis/efectos de los fármacos , Compuestos de Bencidrilo/toxicidad , Fibroblastos/citología , Fibroblastos/efectos de los fármacos , Histonas/metabolismo , Peróxido de Hidrógeno/toxicidad , Metilación/efectos de los fármacos , Ratones , Fenoles/toxicidad , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Receptores de Estrógenos/metabolismo , Receptores Acoplados a Proteínas G/metabolismo
10.
Org Lett ; 15(16): 4150-3, 2013 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-23905884

RESUMEN

AgOTf-catalyzed intramolecular cyclization of phenoxyethynyl diols proceeded under mild conditions to afford the multisubstituted α,ß-unsaturated-γ-lactones in 55-98% yields. This method was also applicable to the synthesis of α,ß-unsaturated-δ-lactones. A similar cyclization proceeded when AgOTf was replaced with a stoichiometric amount of N-bromosuccinimide to furnish the α-bromo-substituted α,ß-unsaturated lactones.


Asunto(s)
Lactonas/síntesis química , Catálisis , Ciclización , Lactonas/química , Mesilatos/química , Estructura Molecular , Estereoisomerismo
11.
J Biosci Bioeng ; 108(4): 286-92, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19716516

RESUMEN

Well-conserved three consecutive Pro residues (Pro247-249) in the NADH-binding subdomain of NADH-cytochrome b(5) reductase were proposed to form a basal part of the NADH-binding site. To investigate the structural and mechanistic roles of these residues, we expressed site-directed mutants for a soluble domain of the porcine enzyme where each of the residues was replaced with either Ala or Leu residue, respectively, using a heterologous expression system in Escherichia coli. Six mutants (P247A, P247L, P248A, P248L, P249A, and P249L) were produced as a fusion protein containing a 6xHis-tag sequence at the NH(2)-terminus and were purified to homogeneity with a stoichiometric amount of bound FAD. Mutations were each confirmed for the purified proteins by MALDI-TOF mass spectrometry. Steady-state kinetic analyses for NADH:ferricyanide reductase and NADH:cytochrome b(5) reductase acitivities were conducted for all the mutants. Substitution of Pro247 with Leu residue was found to significantly decrease k(cat) with slight increase in K(m) for the physiological electron donor NADH. However, K(m) values for the electron acceptors (both cytochrome b(5) and ferricyanide) of P247L were found to be decreased significantly. Such changes were not observed for P247A or other four mutants. These results suggested that Pro247 among the three consecutive Pro residues has the most important role for the formation of a binding site cavity and that only a slight change in the side-chain volume at this residue from Ala to Leu residue affected the electron transfer reaction from NADH and, further, on the recognition of ferricytochrome b(5).


Asunto(s)
Citocromo-B(5) Reductasa/metabolismo , NAD/metabolismo , Prolina/metabolismo , Secuencia de Aminoácidos , Sustitución de Aminoácidos , Animales , Sitios de Unión , Citocromo-B(5) Reductasa/química , Citocromo-B(5) Reductasa/genética , Citocromos b5/metabolismo , Cartilla de ADN , Cinética , Leucina , Modelos Moleculares , Datos de Secuencia Molecular , Mutagénesis Sitio-Dirigida , Unión Proteica , Conformación Proteica , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Porcinos
12.
Arzneimittelforschung ; 56(3): 258-66, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16618019

RESUMEN

Although breath test using 13C-labeled urea (CAS 57-13-6, UBT) is becoming popular for the diagnosis of Helicobacter pylori (H. pylori) infection, disposition of exogenously given urea is not fully understood. The purpose of the present study is to elucidate the disposition of exogenous urea and to consider its relation with the UBT safety and biobehavior of endogenous urea. With 14C-labeled urea ([14C]urea), the absorption, distribution, metabolism and excretion including that into breathed air after its administration in trace to large doses in rats were investigated. [14C]Urea was given to fasted and non-fasted rats through intravenous and oral routes. It was found that the disposition of exogenous [14C]urea behaves in a similar way as endogenous urea, and a sufficiently large capacity for disposing urea in rats was suggested from the linear pharmacokinetics within the wide dose range of [14C]urea (2-1000 mg/kg). The safety of urea in UBT was also revealed by consideration of its dose and human urea body pool. It was also suggested that diet stimulates both systemic (as observed after the intravenous dose) and pre-systemic (as with the oral route) decompositions of urea into carbon dioxide and ammonia, but does not affect the renal elimination and distribution pattern in rat tissues. The findings in this study provide us with the quantitative information concerning not only the safety and disposition of urea as a diagnostic agent, but also the biobehavior of endogenous urea in ureotelism.


Asunto(s)
Dieta , Urea/farmacocinética , Administración Oral , Animales , Biotransformación , Pruebas Respiratorias , Ayuno , Heces/química , Inyecciones Intravenosas , Absorción Intestinal , Masculino , Ratas , Ratas Sprague-Dawley , Distribución Tisular , Urea/administración & dosificación , Urea/metabolismo
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