Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 23
Filtrar
1.
ACS Pharmacol Transl Sci ; 6(10): 1471-1479, 2023 Oct 13.
Artículo en Inglés | MEDLINE | ID: mdl-37854622

RESUMEN

The pseudokinase mixed-lineage kinase domain-like protein plays a crucial role in programmed cell death via necroptosis. We developed a novel mixed-lineage kinase domain-like inhibitor, P28, which demonstrated potent necroptosis inhibition and antifibrotic effects. P28 treatment directly inhibited mixed-lineage kinase domain-like phosphorylation and oligomerization after necroptosis induction, inhibited immune cell death after necroptosis, and reduced the expression of adhesion molecules. Additionally, P28 treatment reduced the level of activation of hepatic stellate cells and the expression of hepatic fibrosis markers induced by necroptosis stimulation. Unlike the necrosulfonamide treatment, the P28 treatment did not induce cytotoxicity. Finally, the cysteine covalent bonding of P28 was confirmed by liquid chromatography-tandem mass spectrometry.

2.
Genes Genomics ; 43(8): 937-945, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-34027569

RESUMEN

BACKGROUND: The folate metabolism that converts homocysteine to methionine is closely related to the accumulation of homocysteine. Increased homocysteine levels lead to an impaired antithrombotic function of the vascular endothelium and uterine-placental circulation, resulting in abnormal pregnancy outcomes. Previous studies have reported that gene polymorphisms in folate metabolism are associated with the development of preterm birth (PTB) in various populations. OBJECTIVE: we performed a case-control study to evaluate the association between five polymorphisms in folate metabolic genes (MTHFR, MTR, MTRR, TCN2) and PTB. METHODS: In this study, a total of 254 subjects were analyzed (111 patients with PTB and 143 women at ≥ 38 weeks of gestation). Genotype and allele frequency differences between patients and control groups and the Hardy-Weinberg equilibrium were assessed using a Chi-square test. For evaluation indicators, odds ratios (ORs) of 95% confidence intervals (CI) were estimated. In addition, we analyzed the combined genotype frequencies of SNPs of folate-metabolizing genes to measure gene-gene interactions for PTB. RESULTS: Our results showed that the MTR rs1805087 GG (p = 0.031), and TCN2 rs1801198 CG genotype (OR 0.53, 95% CI 0.288-0.980, p = 0.042) were significantly associated with PTB. The MTHFR rs4846049 AA showed a marginal trend toward significance (OR 0.15, 95% CI 0.018-1.205, p = 0.041). In particular, the combined genotypes, including MTHFR rs1537514 CC-MTRR rs1801394 GG, MTHFR rs1537514 CC-TCN2 rs1801198 CG, and MTR rs1805087 AA-TCN2 rs1801198 CG, have significant interactions with PTB (OR 0.49, 95% CI 0.248-0.992, p < 0.05). CONCLUSION: The polymorphisms of folate metabolic genes may have a genetic association with the development of PTB in Korean women. A larger sample set and functional studies are required to further elucidate our findings.


Asunto(s)
5-Metiltetrahidrofolato-Homocisteína S-Metiltransferasa/genética , Predisposición Genética a la Enfermedad , Metilenotetrahidrofolato Reductasa (NADPH2)/genética , Nacimiento Prematuro/genética , Transcobalaminas/genética , Alelos , Femenino , Ferredoxina-NADP Reductasa/genética , Ácido Fólico/genética , Ácido Fólico/metabolismo , Frecuencia de los Genes , Estudios de Asociación Genética , Genotipo , Humanos , Recién Nacido , Placenta/metabolismo , Placenta/patología , Polimorfismo de Nucleótido Simple/genética , Proteína de Unión al Tracto de Polipirimidina/genética , Embarazo , Nacimiento Prematuro/epidemiología , Nacimiento Prematuro/metabolismo , Nacimiento Prematuro/patología , República de Corea/epidemiología
3.
Int J Mol Sci ; 21(9)2020 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-32375257

RESUMEN

Kaempferol (KO) and kaempferol 7-O-rhamnoside (KR) are natural products from various oriental herbs such as Geranii Herba. Previous studies have reported some biological activities of KO and KR; however, their effects on PD-1/PD-L1 interaction have not been reported yet. To elucidate their inhibitory activities on PD-1/PD-L1 protein-protein interaction (PPI), biochemical assays including competitive ELISA and biolayer interferometry (BLI) systems were performed. Cellular PD-1/PD-L1 blocking activity was measured in a co-culture system with PD-1 Jurkat and PD-L1/aAPC CHO-K1 cells by T-cell receptor (TCR) activation-induced nuclear factor of activated T cells (NFAT)-luciferase reporter assay. The detailed binding mode of action was simulated by an in silico docking study and pharmacophore analysis. Competitive ELISA revealed that KO and its glycoside KR significantly inhibited PD-1/PD-L1 interaction. Cellular PD-1/PD-L1 blocking activity was monitored by KO and KR at non-cytotoxic concentration. Surface plasmon resonance (SPR) and biolayer interferometry (BLI) analysis suggested the binding affinity and direct inhibition of KR against PD-1/PD-L1. An in silico docking simulation determined the detailed mode of binding of KR to PD-1/PD-L1. Collectively, these results suggest that KR could be developed as a potent small molecule inhibitor for PD-1/PD-L1 blockade.


Asunto(s)
Antígeno B7-H1/metabolismo , Inhibidores de Puntos de Control Inmunológico/farmacología , Quempferoles/farmacología , Receptor de Muerte Celular Programada 1/metabolismo , Animales , Antígeno B7-H1/química , Células CHO , Cricetinae , Cricetulus , Humanos , Células Jurkat , Simulación del Acoplamiento Molecular , Receptor de Muerte Celular Programada 1/química , Unión Proteica/efectos de los fármacos
4.
Genes Genomics ; 42(7): 743-750, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32445180

RESUMEN

BACKGROUND: Preterm birth (PTB) is a major adverse pregnancy outcome and largely contributes to increasing neonatal and maternal mortality. Genetic and environmental factors may play an important role in the development of PTB. Numerous studies have shown that immune genes related to the immune system, such as IL-6, IL-10, and TNFα, are associated with the occurrence of PTB. OBJECTIVE: We examined genetic associations between IL-6 rs1800796, IL-10 rs1800872, and TNFα rs1800630 polymorphisms and PTB in Korean women. METHODS: In this study, 115 PTB patients and 147 controls were analyzed. The genotyping of three SNPs was performed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). RESULTS: Our result showed that the rs1800872 polymorphism was significantly associated with the development of PTB in genotype frequency (odds ratio (OR) 1.71, 95% confidence interval (CI) 1.01-2.90, p = 0.046). We also found a significant association in an analysis of combined genotypes (rs1800796 CC, rs1800872 CA, and rs1800630 CA) (OR 7.43, 95% CI 2.06-26.84, p = 0.001). In a correlation analysis, rs1800630 A allele was significantly related with the increased birth weight (g) within PTB patients (p = 0.005). CONCLUSION: Our results imply possible relationships between the rs1800796, rs1800872, and rs1800630 polymorphisms and the development of PTB.


Asunto(s)
Predisposición Genética a la Enfermedad , Interleucina-10/genética , Interleucina-6/genética , Polimorfismo de Nucleótido Simple , Nacimiento Prematuro/genética , Factor de Necrosis Tumoral alfa/genética , Adulto , Femenino , Humanos , Embarazo , República de Corea
5.
J Minim Invasive Surg ; 23(3): 149-151, 2020 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-35602380

RESUMEN

Reports on the laparoscopic treatment for colonic intussusception are exceedingly rare. We report a case of colonic intussusception caused by sigmoid colon cancer which was treated with a laparoscopic approach. A 76-year-old man visited an emergency room with the chief complaint of lower abdominal pain. He was diagnosed with colonic intussusception probably due to sigmoid colon cancer on a CT scan. Upon laparoscopic exploration, sigmoid colon intussusception was noted. Manual reduction was impossible because the colonic walls were friable and due to the possibility of a cancerous leading point. Therefore, the bowel was resected with en bloc Hartmann procedure. Pathology of the resected specimen revealed a tumor measuring 4.5 cm in size and comprising moderately differentiated adenocarcinoma (pT3N0M0, pStage II). The patient's postoperative course was uneventful and was discharged on the 8th day after surgery.

6.
ACS Appl Mater Interfaces ; 11(35): 31786-31792, 2019 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-31408308

RESUMEN

The Sr segregation at the surface of a perovskite La0.6Sr0.4Co0.2Fe0.8O3-δ (LSCF) oxygen electrode is detrimental to the electrochemical performance and durability of energy conversion devices such as solid oxide fuel cells. However, a quantitative correlation of degradation of the oxygen surface exchange kinetics with Sr precipitation formation at the LSCF surface is not clearly understood yet. Herein, the correlation of the time-dependent degradation mechanisms of the LSCF catalysts with respect to Sr segregation phenomenon at the surface were investigated at 800 °C for a prolonged annealing time (∼800 h) by combining in situ electrochemical measurements, and ex situ chemical and structural analyses at the multiscale. The in situ monitored surface exchange coefficient (kchem) was found to drastically drop by ∼86% over the 800 h, and it was accompanied by the formation of Sr-containing secondary phases on the bulk LSCF surface, as expected. However, the estimated coverage of Sr segregation on the LSCF surface was only ∼15%, even after 800 h of aging time, showing significant deviation from the kchem degradation rate (∼86%). The surface chemistry evolution at the clean surface area, which is believed to be electrochemically active, was further analyzed on the nanoscale. The quantified results showed that the Sr elemental fraction of the A-site at the outermost surface of the LSCF samples was becoming deficient from ∼4.0 at 0 h to ∼0.27 at 800 h annealing. Interestingly, the time-dependent behavioral tendencies between kchem degradation and surface Sr fractional changes were highly analogous. Thus, our results suggest that this Sr deficiency at the clean surface region more dominantly impacts the degradation process rather than an electrochemical activity passivation by the SrOx precipitates, which has been shown to be a major degradation mechanism of LSCF performance.

7.
Medicina (Kaunas) ; 55(6)2019 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-31185683

RESUMEN

BACKGROUND AND OBJECTIVES: The ACE gene encodes the angiotensin-converting enzyme (ACE), a component of the renin-angiotensin system. Increased ACE activity may cause abnormal regulation of placental circulation and angiogenesis, resulting in adverse pregnancy outcomes. Previous studies have reported that the insertion/deletion (I/D) polymorphism of the ACE gene is associated with the development of preterm birth (PTB). However, results of the association between ACE gene I/D and PTB are inconsistent in various populations. Therefore, we performed a case-control study and a meta-analysis to evaluate the association between ACE I/D polymorphism and PTB. Materials and Methods: We analyzed a total of 254 subjects (111 patients with PTB and 143 women at ≥38 weeks gestation) for the case-control study. For the meta-analysis, we searched Google Scholar, PubMed, and NCBI databases with the terms "ACE," "angiotensin-converting enzyme," "preterm birth," "preterm delivery," and their combinations. Results: Our results of the case-control study indicated that ACE I/D polymorphism is significantly associated with PTBs in the overdominant genetic model (odds ratio (OR) 0.57, 95% confidence interval (CI) 0.347-0.949, p = 0.029) and that the ID genotype of ACE I/D polymorphism has a protective effect for PTB (OR 0.57, 95% CI 0.333-0.986, p = 0.043). Similarly, the meta-analysis showed that the OR for the ACE gene ID genotype was 0.66 (95% CI 0.490-0.900, p < 0.01). Conclusion: The ACE gene ID genotype has a significant association with PTB and is a protective factor for PTB. A larger sample set and functional studies are required to further elucidate of our findings.


Asunto(s)
Peptidil-Dipeptidasa A/análisis , Nacimiento Prematuro/sangre , Adulto , Estudios de Casos y Controles , Femenino , Predisposición Genética a la Enfermedad/epidemiología , Humanos , Recién Nacido , Oportunidad Relativa , Peptidil-Dipeptidasa A/sangre , Peptidil-Dipeptidasa A/genética , Polimorfismo Genético/fisiología , Nacimiento Prematuro/epidemiología , República de Corea/epidemiología
8.
J Minim Invasive Surg ; 22(4): 177-180, 2019 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-35601371

RESUMEN

Pyogenic hepatic abscess caused by an ingested foreign body is extremely uncommon, and reports on the laparoscopic treatment for it are very rare. We report here on a case of hepatic abscess caused by an ingested chicken bone which was treated with a laparoscopic approach. A 61-year-old man visited an emergency room with the chief complaints of high fever. He was diagnosed with pyogenic liver abscess that contained a sharp calcified foreign body seen on a CT-scan. At first, percutaneous transhepatic drainage of the abscess was performed to achieve recovery of the patient's condition. Subsequent laparoscopic exploration found and removed the foreign body in the lesser sac. The foreign body turned out to be an ingested chicken bone. The patient was discharged on the 10th day after surgery.

9.
Obstet Gynecol Sci ; 61(4): 533-536, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30018910

RESUMEN

As cosmetic procedures receive increasing attention from the media, female genital cosmetic surgery (FGCS) has become quite popular in Korea. The safety and efficacy of these surgeries and procedures have yet to be thoroughly documented. We report a case of a 47-year-old woman who underwent a vaginal sling implantation, which resulted in the misdiagnosis of a rectal subepithelial tumor during endoscopic mucosal resection (EMR). This patient suffered an iatrogenic rectal perforation during the EMR, which necessitated an exploratory operation. The sling implant was removed via the vaginal approach, and a primary repair of the vaginal and rectal walls was performed. The patient subsequently showed no sign of complication at her 6-month follow-up. Patients need to be educated about the importance of reporting a history of FGCS prior to undergoing surgical or endoscopic procedures. Also, physicians have to check the medical history of patient thoroughly to avoid misdiagnoses and unnecessary treatment.

10.
Comput Methods Programs Biomed ; 157: 137-143, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29477422

RESUMEN

BACKGROUND AND OBJECTIVE: Attention-deficit hyperactivity disorder (ADHD) is a neurodevelopmental disorder hypothesized to involve impaired visuospatial working memory (VSWM). However, there are few studies utilizing neuropsychological tests to measure VSWM in ADHD adolescents. The Rey-Osterrieth complex figure test (ROCF) is commonly used as a neuropsychological test to assess visuospatial working memory for individuals with ADHD. We assessed working memory using the ROCF test on a digital Galaxy tablet with the technically new Gaussian filter method. METHODS: Thirty adolescents with ADHD and 30 healthy control adolescents were recruited for participation in the current study. All adolescents were assessed with K-WISC-IV, Children's depression inventory, and the Korean ADHD rating scale. All adolescents were asked to copy the ROCF from paper onto a Galaxy tablet screen using a wireless pen. RESULTS: There was a significant difference in representative value of the deviation of the original images from template images (R-value) in copy and delayed recall between ADHD adolescents and healthy adolescents. There was no significant difference in R-value of immediate recall between ADHD adolescents and healthy adolescents. In all adolescents (ADHD and healthy) and ADHD adolescents, the R-value of copy was negatively correlated with visuospatial index and working memory index, and the R-value of delayed recall was negatively correlated with WMI. The R-value of copy and delayed recall was positively correlated with K-ARS in all adolescents and ADHD adolescents. CONCLUSIONS: ADHD adolescents showed differences in the R-values of copy and delayed recall in the digital ROCF version compared to healthy adolescents. The digital ROCF assessment tool can represent different patterns of visuospatial working memory abilities in ADHD adolescents compared to healthy adolescents.


Asunto(s)
Trastorno por Déficit de Atención con Hiperactividad/psicología , Computadoras de Mano/estadística & datos numéricos , Memoria a Corto Plazo , Pruebas Neuropsicológicas , Percepción Espacial , Percepción Visual , Adolescente , Trastorno por Déficit de Atención con Hiperactividad/fisiopatología , Estudios de Casos y Controles , Humanos , Masculino
11.
Medicina (Kaunas) ; 53(6): 380-385, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29428336

RESUMEN

BACKGROUND AND OBJECTIVE: The MTHFR gene encodes the methylenetetrahydrofolate reductase known to be involved in the homocysteine-methionine pathway. It has been reported that the deficiency of MTHFR activity may cause hyperhomocysteinemia which results in adverse pregnancy outcomes. Previous studies reported a correlation between the MTHFR gene polymorphisms (677 T/C and 1298 A/C) and lower MTHFR activity and its association with preterm birth in various populations. Since these results were conflicting, we analyzed the genetic association of MTHFR gene 677 T/C and 1298 A/C polymorphisms with preterm birth in Korean women. MATERIALS AND METHODS: The subjects for case-control study were collected a total of 226 Korean women (98 preterm-birth patients and 128 controls). Genotype frequency differences between the case and the control were assessed using chi-square tests. Mann-Whitney t-test was used to estimate the effects of 1298 A/C genotype on clinicopathological characteristics (systolic blood pressure, diastolic blood pressure, birth weight, and gestational age at delivery) in preterm-birth patients. RESULTS: Our results showed that the MTHFR 677 C/T polymorphism was significantly associated with preterm-birth patients in the analysis of genotype frequency (P=0.044) and the over-dominant model (OR=0.54; 95% CI, 0.320-0.920; P=0.023). The recessive model showed a marginal trend toward significance (OR=0.47; 95% CI, 0.220-1.010; P=0.046). The 1298 A/C polymorphism was also associated with reduced preterm-birth risk in the recessive model (P=0.032). In the correlation analysis, the 1298 C allele was significantly associated with increasing of gestational age at delivery in preterm-birth patients (P=0.034). CONCLUSIONS: Our findings suggested that the MTHFR gene 677 C/T and 1298 A/C polymorphisms might have protective effects for preterm birth in the Korean women.


Asunto(s)
Frecuencia de los Genes , Metilenotetrahidrofolato Reductasa (NADPH2) , Nacimiento Prematuro , Adulto , Alelos , Pueblo Asiatico/genética , Estudios de Casos y Controles , Femenino , Predisposición Genética a la Enfermedad , Genotipo , Humanos , Metilenotetrahidrofolato Reductasa (NADPH2)/genética , Oportunidad Relativa , Embarazo , Nacimiento Prematuro/genética
12.
Obstet Gynecol Sci ; 59(6): 554-558, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27896262

RESUMEN

The incidence of uterine arteriovenous malformation (AVM) is rare. However, it is clinically significant in that it can cause life-threatening vaginal bleeding. We report a case of a large uterine AVM with positive serum beta-human chorionic gonadotropin. A presumptive diagnosis was made; a uterine AVM accompanied by, early pregnancy or retained product of conception. Because this uterine AVM was extensive, transcatheter arterial embolization of both uterine arteries and extra-uterine feeding arteries was performed. Three months after undergoing transcatheter arterial embolization, complete resolution of the uterine AVM was confirmed without major complication.

13.
Obstet Gynecol Sci ; 59(5): 403-6, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27668205

RESUMEN

Aortic dissection is very rare in obstetrics, but it is a fatal disease. A 37-weeks primigravida woman with dyspnea and pitting edema presented to our emergency room. The patient was diagnosed with preeclampsia and underwent an emergency cesarean section under spinal anesthesia. The patient complained of severe dyspnea after the cesarean section, and the chest computed tomography scan was done. With the finding of aortic dissection, cardiopulmonary arrest occurred 5 hours after the cesarean section, and the patient died without reaction to cardio-pulmonary resuscitation. If a patient with preeclampsia complains of severe dyspnea or chest pain, aortic dissection needs to be suspected and a diagnosis should not be delayed.

14.
Protein Expr Purif ; 126: 122-126, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-27371359

RESUMEN

In enterohemorrhagic Escherichia coli (EHEC), the QseEF two-component system causes attaching and effacing (AE) lesion on epithelial cells. QseE histidine kinase senses the host hormone epinephrine, sulfate, and phosphate; it also regulates QseF response regulator, which activates LEE gene that encodes AE lesion. In order to understand the recognition of ligand molecules and signal transfer mechanism in pathogenic bacteria, structural studies of the sensor domain of QseE of Escherichia coli should be conducted. In this study, we describe the overexpression, purification, and structural and biophysical properties of the sensor domain of QseE. The fusion protein had a 6×His tag at its N-terminus; this protein was overexpressed as inclusion bodies in E. coli BL21 (DE3). The protein was denatured in 7M guanidine hydrochloride and refolded by dialysis. The purification of the refolded protein was carried out using Ni-NTA affinity column and size-exclusion chromatography. Thereafter, the characteristics of the refolded protein were determined from NMR, CD, and MALS spectroscopies. In a pH range of 7.4-5.0, the folded protein existed in a monomeric form with a predominantly helical structure. (1)H-(15)N HSQC NMR spectra shows that approximately 93% backbone amide peaks are detected at pH 5.0, suggesting that the number of backbone signals is sufficient for NMR studies. These data might provide an opportunity for structural and functional studies of the sensor domain of QseE.


Asunto(s)
Escherichia coli Enterohemorrágica/enzimología , Proteínas de Escherichia coli , Expresión Génica , Replegamiento Proteico , Receptores Adrenérgicos , Escherichia coli Enterohemorrágica/genética , Proteínas de Escherichia coli/biosíntesis , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/aislamiento & purificación , Concentración de Iones de Hidrógeno , Resonancia Magnética Nuclear Biomolecular , Dominios Proteicos , Estructura Secundaria de Proteína , Receptores Adrenérgicos/biosíntesis , Receptores Adrenérgicos/genética , Receptores Adrenérgicos/aislamiento & purificación , Proteínas Recombinantes de Fusión/biosíntesis , Proteínas Recombinantes de Fusión/química , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/aislamiento & purificación
15.
Nucleic Acids Res ; 44(6): 2936-48, 2016 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-26792893

RESUMEN

Z-DNA binding proteins (ZBPs) play important roles in RNA editing, innate immune response and viral infection. Structural and biophysical studies show that ZBPs initially form an intermediate complex with B-DNA for B-Z conversion. However, a comprehensive understanding of the mechanism of Z-DNA binding and B-Z transition is still lacking, due to the absence of structural information on the intermediate complex. Here, we report the solution structure of the Zα domain of the ZBP-containing protein kinase from Carassius auratus(caZαPKZ). We quantitatively determined the binding affinity of caZαPKZ for both B-DNA and Z-DNA and characterized its B-Z transition activity, which is modulated by varying the salt concentration. Our results suggest that the intermediate complex formed by caZαPKZ and B-DNA can be used as molecular ruler, to measure the degree to which DNA transitions to the Z isoform.


Asunto(s)
ADN Forma B/química , ADN de Forma Z/química , Proteínas de Unión al ADN/química , Proteínas de Peces/química , Carpa Dorada/metabolismo , Proteínas Quinasas/química , Secuencia de Aminoácidos , Animales , Sitios de Unión , Clonación Molecular , ADN Forma B/metabolismo , ADN de Forma Z/metabolismo , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Proteínas de Peces/genética , Proteínas de Peces/metabolismo , Expresión Génica , Cinética , Modelos Moleculares , Datos de Secuencia Molecular , Unión Proteica , Proteínas Quinasas/genética , Proteínas Quinasas/metabolismo , Estructura Secundaria de Proteína , Estructura Terciaria de Proteína , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Alineación de Secuencia , Cloruro de Sodio/química , Termodinámica
16.
PLoS One ; 9(9): e107168, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25203403

RESUMEN

The DraR/DraK two-component system was found to be involved in the differential regulation of antibiotic biosynthesis in a medium-dependent manner; however, its function and signaling and sensing mechanisms remain unclear. Here, we describe the solution structure of the extracellular sensor domain of DraK and suggest a mechanism for the pH-dependent conformational change of the protein. The structure contains a mixed alpha-beta fold, adopting a fold similar to the ubiquitous sensor domain of histidine kinase. A biophysical study demonstrates that the E83, E105, and E107 residues have abnormally high pKa values and that they drive the pH-dependent conformational change for the extracellular sensor domain of DraK. We found that a triple mutant (E83L/E105L/E107A) is pH independent and mimics the low pH structure. An in vivo study showed that DraK is essential for the recovery of the pH of Streptomyces coelicolor growth medium after acid shock. Our findings suggest that the DraR/DraK two-component system plays an important role in the pH regulation of S. coelicolor growth medium. This study provides a foundation for the regulation and the production of secondary metabolites in Streptomyces.


Asunto(s)
Proteínas Quinasas/metabolismo , Streptomyces coelicolor/metabolismo , Histidina Quinasa , Concentración de Iones de Hidrógeno , Estructura Terciaria de Proteína , Transducción de Señal/fisiología
17.
Biochem Biophys Res Commun ; 447(3): 400-6, 2014 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-24727454

RESUMEN

The umbilical cord blood (UCB) cells have been reported to secrete therapeutic signals, including a series of neurotrophic factors. This suggests the cell source provides suitable therapeutic environments for nerve regeneration that ultimately finds a possible cell therapy for nerve tissue. In this study, we observe a collagen hydrogel provides human UCB cells a proper 3D environment that stimulates the release of various neurotrophic factors. When compared to 2D culture, the 3D hydrogel culture significantly enhanced the expression of a series of neurotrophic factors, including neurotrophins, nerve growth factor, brain-derived neurotrophic factor, and ciliary neurotrophic factor as verified by the gene and protein analysis. To confirm the effects of neurotrophic factors secretion, we allowed an indirect interaction of the UCB-environment with human neural precursor cells (hNPCs). Results showed significantly enhanced neurite outgrowth of hNPCs. Collectively, our findings demonstrate that the collagen-based 3D hydrogel provides excellent environment for UCB-derived cells to release neurotrophic factors that will be ultimately useful for the neural repair and regeneration purposes.


Asunto(s)
Colágeno/farmacología , Sangre Fetal/efectos de los fármacos , Hidrogel de Polietilenoglicol-Dimetacrilato/farmacología , Factores de Crecimiento Nervioso/metabolismo , Células-Madre Neurales/fisiología , Neuritas/fisiología , Células Cultivadas , Microambiente Celular , Técnicas de Cocultivo , Sangre Fetal/metabolismo , Citometría de Flujo , Humanos , Factores de Crecimiento Nervioso/genética
18.
Biochem Biophys Res Commun ; 428(1): 137-41, 2012 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-23079620

RESUMEN

The Z-DNA binding domain of human ADAR1 (Zα(ADAR1)) preferentially binds Z-DNA rather than B-DNA with high binding affinity. Here, we have carried out chemical shift perturbation and backbone dynamics studies of Zα(ADAR1) in the free form and in complex with three DNA duplexes, d(CGCGCG)(2), d(CACGTG)(2), and d(CGTACG)(2). This study reveals that Zα(ADAR1) initially binds to d(CGCGCG)(2) through the distinct conformation, especially in the unusually flexible ß1-loop-α2 region, from the d(CGCGCG)(2)-(Zα(ADAR1))(2) complex. This study also suggests that Zα(ADAR1) exhibits a distinct conformational change during the B-Z transition of non-CG-repeat DNA duplexes with low binding affinities compared to the CG-repeat DNA duplex.


Asunto(s)
Adenosina Desaminasa/química , ADN de Forma Z/química , Secuencia de Aminoácidos , Islas de CpG , ADN Forma B/química , Humanos , Datos de Secuencia Molecular , Resonancia Magnética Nuclear Biomolecular , Unión Proteica , Estructura Terciaria de Proteína , Proteínas de Unión al ARN , Secuencias Repetitivas de Ácidos Nucleicos
19.
Thyroid ; 19(3): 305-8, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19265502

RESUMEN

BACKGROUND: Struma ovarii is a highly specialized form of mature ovarian teratoma consisting of thyroid tissue and exhibiting all the histological features of the thyroid gland. Malignant transformation of thyroid tissue in struma ovarii and metastasis are extremely uncommon. In rare cases, benign thyroid tissue may spread to the peritoneal cavity, and pathologic examination of the peritoneal implants shows multiple nodules of varying sizes of mature thyroid tissue similar to struma ovarii. This condition is termed "peritoneal strumosis." SUMMARY: We report a 49-year-old woman with struma ovarii complicated by peritoneal strumosis with thyrotoxicosis. After surgical resection of the struma ovarii and peritoneal strumosis the patient became euthyroid. CONCLUSION: To the best of our knowledge this is the first report of a patient with peritoneal strumosis complicated by thyrotoxicosis. The relative contribution to circulating thyroid hormones by the patient's struma ovarii as compared to the peritoneal strumosis is not known.


Asunto(s)
Neoplasias Ováricas/complicaciones , Cavidad Peritoneal/patología , Estruma Ovárico/complicaciones , Tirotoxicosis/complicaciones , Femenino , Humanos , Persona de Mediana Edad , Neoplasias Ováricas/diagnóstico por imagen , Neoplasias Ováricas/patología , Ovario/patología , Cavidad Peritoneal/diagnóstico por imagen , Cintigrafía , Estruma Ovárico/diagnóstico por imagen , Estruma Ovárico/patología , Tirotoxicosis/radioterapia , Tirotoxicosis/cirugía , Imagen de Cuerpo Entero
20.
Cell Transplant ; 16(6): 629-37, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17912954

RESUMEN

Glycogen storage disease type I (GSD-I) is a group of autosomal recessive disorders with an incidence of 1 in 100,000. The two major subtypes are GSD-Ia, caused by a deficiency of glucose-6-phosphatase (G6Pase), and GSD-Ib, caused by a deficiency of glucose-6-phosphate transporter (G6PT). We report that a substantial improvement was achieved following several infusions of hepatocytes in a patient with GSD-Ib. Hepatocytes were isolated from the unused cadaveric whole livers of two donors. At the first transplantation, approximately 2 x 10(9) cells (2% of the estimated recipient's total hepatocytes) were infused. Seven days later 1 x 10(9) (1% of liver mass) cryopreserved hepatocytes from the same donor were infused, and an additional 3 x 10(9) (3% of liver mass) cells from the second donor were infused 1 month after the second transplantation. After the hepatocyte transplantation, the patient showed no hypoglycemic symptoms despite the discontinuation of cornstarch meals. Liver biopsies on posttransplantation days 20 and 250 showed a normal level of glucose-6-phosphatase activity in presolubilization assay that was very low before transplantation. This was the first and successful clinical hepatocyte transplantation in Korea. In this study, hepatocyte transplantation allowed a normal diet in a patient with GSD-Ib, with substantial improvement in their quality of life. Hepatocyte transplantation might be an alternative to liver transplantation and dietary therapy in GSD-Ib.


Asunto(s)
Glucosa-6-Fosfatasa/metabolismo , Glucosa-6-Fosfato/metabolismo , Enfermedad del Almacenamiento de Glucógeno Tipo I/metabolismo , Enfermedad del Almacenamiento de Glucógeno Tipo I/terapia , Hepatocitos/trasplante , Adolescente , Cadáver , Estudios de Seguimiento , Glucosa-6-Fosfato/deficiencia , Enfermedad del Almacenamiento de Glucógeno Tipo I/patología , Hepatocitos/enzimología , Humanos , Inmunosupresores/uso terapéutico , Corea (Geográfico) , Hígado/citología , Hígado/inmunología , Masculino , Calidad de Vida , Inmunología del Trasplante/efectos de los fármacos , Trasplantes , Resultado del Tratamiento
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...