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1.
Heliyon ; 9(1): e12931, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36644679

RESUMO

Aim: To develop self-management education for preventing coronavirus disease 2019 (COVID-19) in patients on hemodialysis and to verify its effects. Background: During the current pandemic, studies on various areas, such as infection control in dialysis units, infection rates, clinical characteristics, treatment progress, and the emotional and psychological states of dialysis patients, have been actively reported. However, experimental research verifying the effects of interventions on infection prevention in hemodialysis patients is very rare. Methods: This study included 34 patients on hemodialysis in a South Korean general hospital (18 in the experimental group and 16 in the control group). Data were collected from September to October 2021. The experimental group was provided with self-care behavior for infection prevention education for 8 weeks, and the control group was provided with usual nursing care. Results: The patients on hemodialysis showed moderate fear of COVID-19, good compliance with patient role behavior and self-management efficacy, and poor handwashing practice. After the intervention, there were no significant differences concerning fear of COVID-19, compliance with patient role behavior, and self-management efficacy between the experimental and control groups. However, confidence in handwashing (subjective norm) and proper handwashing practice improved significantly in the experimental group compared with the control group. Conclusion: The infection prevention education developed in this study positively affected confidence in handwashing and proper handwashing practice in patients undergoing hemodialysis. This intervention can be used in various clinical settings where care is provided for patients with chronic illness, including those on hemodialysis.

2.
Artigo em Inglês | MEDLINE | ID: mdl-34639648

RESUMO

The purpose of this study was to investigate the relationships among burden, depression, awareness of information (AIC), and safety behavior among hemodialysis patients in Korea during the COVID-19 pandemic. The study participants included 149 patients who received hemodialysis at seven general hospitals in Korea between January and February 2021. A structured questionnaire was used to survey their levels of burden, depression, AIC, adherent safety behavior (ASB), and dysfunctional safety behavior (DSB). The study results showed that the influencing factors of ASB for COVID-19 were AIC (ß = 0.265, p < 0.001), the burden of "not receiving hemodialysis on time" (ß = 0.233, p = 0.008), and the burden of "social exclusion of hemodialysis patients" (ß = 0.186, p = 0.032). The influencing factors of DSB were the burden of "social exclusion of hemodialysis patients" (ß = 0.258, p = 0.003) and AIC (ß = 0.217, p = 0.004). As the COVID-19 pandemic continues, the latest evidence-based information must be provided to hemodialysis patients to promote self-care and prevention behavior that encourages ASB and discourages DSB.


Assuntos
COVID-19 , Pandemias , Depressão/epidemiologia , Humanos , Diálise Renal/efeitos adversos , República da Coreia/epidemiologia , SARS-CoV-2
3.
Iran J Radiol ; 13(1): e30909, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27127579

RESUMO

BACKGROUND: In preoperative assessment of breast cancer, MRI has been shown to identify more additional breast lesions than are detectable using conventional imaging techniques. The characterization of additional lesions is more important than detection for optimal surgical treatment. Additional breast lesions can be included in focus, mass, and non-mass enhancement (NME) on MRI. According to the fifth edition of the breast imaging reporting and data system (BI-RADS®), which includes several changes in the NME descriptors, few studies to date have evaluated NME in preoperative assessment of breast cancer. OBJECTIVES: We investigated the diagnostic accuracy of BI-RADS descriptors in predicting malignancy for additional NME lesions detected on preoperative 3T dynamic contrast enhanced MRI (DCE-MRI) in patients with newly diagnosed breast cancer. PATIENTS AND METHODS: Between January 2008 and December 2012, 88 patients were enrolled in our study, all with NME lesions other than the index cancer on preoperative 3T DCE-MRI and all with accompanying histopathologic examination. The MRI findings were analyzed according to the BI-RADS MRI lexicon. We evaluated the size, distribution, internal enhancement pattern, and location of NME lesions relative to the index cancer (i.e., same quadrant, different quadrant, or contralateral breast). RESULTS: On histopathologic analysis of the 88 NME lesions, 73 (83%) were malignant and 15 (17%) were benign. Lesion size did not differ significantly between malignant and benign lesions (P = 0.410). Malignancy was more frequent in linear (P = 0.005) and segmental (P = 0.011) distributions, and benignancy was more frequent in focal (P = 0.004) and regional (P < 0.001) NME lesions. The highest positive predictive value (PPV) for malignancy occurred in segmental (96.8%), linear (95.1%), clustered ring (100%), and clumped (92.0%) enhancement. Asymmetry demonstrated a high positive predictive value of 85.9%. The frequency of malignancy was higher for NME lesions located in the same quadrant with the index cancer (P = 0.006), and benignancy was higher in the contralateral breast (P = 0.015). On multivariate analysis, linear (P = 0.001) and segmental (P = 0.005) distributions were significant predictors of malignancy. CONCLUSION: The possibility of malignancy is strongly indicated when additional NME lesions show linear or segmental enhancement on preoperative 3T DCE-MRI in patients with recently diagnosed breast cancer.

4.
Iran J Radiol ; 12(2): e23911, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25901261

RESUMO

Calcifying aponeurotic fibroma (CAF) is a rare, benign fibroblastic tumor that typically occurs in the palms of the hands and soles of the feet, in children and adolescents. Due to its infiltrative nature, this tumor can mimic malignancy on preoperative magnetic resonance imaging (MRI) and has a predilection for local recurrence. There are very few reports in the literature that describe features of CAF on MRI, especially those arising in the foot. We present an unusual case of a CAF affecting the dorsum of the foot in a four-year-old boy.

5.
Stem Cells ; 32(2): 424-35, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24170349

RESUMO

The pluripotency of embryonic stem cells (ESCs) is maintained by intracellular networks of many pluripotency-associated (PA) proteins such as OCT4, SOX2, and NANOG. However, the mechanisms underlying the regulation of protein homeostasis for pluripotency remain elusive. Here, we first demonstrate that autophagy acts together with the ubiquitin-proteasome system (UPS) to modulate the levels of PA proteins in human ESCs (hESCs). Autophagy inhibition impaired the pluripotency despite increment of PA proteins in hESCs. Immunogold-electron microscopy confirmed localization of OCT4 molecules within autophagosomes. Also, knockdown of LC3 expression led to accumulation of PA proteins and reduction of pluripotency in hESCs. Interestingly, autophagy and the UPS showed differential kinetics in the degradation of PA proteins. Autophagy inhibition caused enhanced accumulation of both cytoplasmic and nuclear PA proteins, whereas the UPS inhibition led to preferentially degrade nuclear PA proteins. Our findings suggest that autophagy modulates homeostasis of PA proteins, providing a new insight in the regulation of pluripotency in hESCs.


Assuntos
Autofagia/genética , Células-Tronco Embrionárias/metabolismo , Células-Tronco Pluripotentes/metabolismo , Linhagem Celular , Proteínas de Homeodomínio/metabolismo , Homeostase , Humanos , Proteína Homeobox Nanog , Fator 3 de Transcrição de Octâmero/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo , Fatores de Transcrição SOXB1/metabolismo , Ubiquitina/genética
6.
PLoS One ; 7(10): e47361, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23056634

RESUMO

B lymphocyte stimulator (BLyS) is a member of the TNF superfamily of cytokines. The biological activity of BLyS is mediated by three cell surface receptors: BR3/BAFF-R, TACI and BCMA. The expression of these receptors is highly restricted to B cells, both normal and malignant. A BLyS-gelonin fusion toxin (BLyS-gel) was generated consisting of the recombinant plant-derived toxin gelonin fused to the N-terminus of BLyS and tested against a large and diverse panel of B-NHL cell lines. Interestingly, B-NHL subtypes mantle cell lymphoma (MCL), diffuse large B cell lymphoma (DLBCL) and B cell precursor-acute lymphocytic leukemia (BCP-ALL) were preferentially sensitive to BLyS-gel mediated cytotoxicity, with low picomolar EC(50) values. BLyS receptor expression did not guarantee sensitivity to BLyS-gel, even though the construct was internalized by both sensitive and resistant cells. Resistance to BLyS-gel could be overcome by treatment with the endosomotropic drug chloroquine, suggesting BLyS-gel may become trapped within endosomal/lysosomal compartments in resistant cells. BLyS-gel induced cell death was caspase-independent and shown to be at least partially mediated by the "ribotoxic stress response." This response involves activation of p38 MAPK and JNK/SAPK, and BLyS-gel mediated cytotoxicity was inhibited by the p38/JNK inhibitor SB203580. Finally, BLyS-gel treatment was shown to localize to sites of disease, rapidly reduce tumor burden, and significantly prolong survival in xenograft mouse models of disseminated BCP-ALL, DLBCL, and MCL. Together, these findings suggest BLyS has significant potential as a targeting ligand for the delivery of cytotoxic "payloads" to malignant B cells.


Assuntos
Fator Ativador de Células B/metabolismo , Linfoma de Células B/tratamento farmacológico , Proteínas Recombinantes de Fusão/farmacologia , Proteínas Recombinantes de Fusão/uso terapêutico , Proteínas Inativadoras de Ribossomos Tipo 1/metabolismo , Animais , Fator Ativador de Células B/genética , Western Blotting , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Feminino , Citometria de Fluxo , Humanos , Camundongos , Camundongos SCID , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Proteínas Inativadoras de Ribossomos Tipo 1/genética , Ensaios Antitumorais Modelo de Xenoenxerto
7.
Biochem Biophys Res Commun ; 410(4): 834-40, 2011 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-21703244

RESUMO

The suprachiasmatic nuclei in the mammalian brain function as the regulators of circadian rhythm and coordinate the peripheral oscillators. Losses of clock genes alter gene expression and behavior. Here, we investigated whether disruption of the circadian clock and glucocorticoid signals would influence the gene expression of major urinary protein (Mup) in mice. Both Mup2 mRNA and protein showed biphasic rhythms with similar phase relationships. However, the peak of the rhythm is shifted in mPeriod2 circadian clock mutant mice. We identified two E-boxes and one glucocorticoid response element (GRE) as regulatory elements for Mup2 transcription. While CLOCK binds to the E-boxes constantly, glucocorticoid receptor was capable of binding to the GRE in a timely manner. All together, our results indicate that Mup2 expression is regulated by both the circadian clock and glucocorticoid.


Assuntos
Relógios Circadianos/fisiologia , Regulação da Expressão Gênica , Glucocorticoides/fisiologia , Proteínas/genética , Elementos Reguladores de Transcrição , Fatores de Transcrição ARNTL/metabolismo , Animais , Proteínas CLOCK/metabolismo , Imunoprecipitação da Cromatina , Relógios Circadianos/genética , Glucocorticoides/farmacologia , Fígado/metabolismo , Camundongos , Camundongos Knockout , Células NIH 3T3 , Proteínas Circadianas Period/genética , Multimerização Proteica , Transcrição Gênica
8.
Blood ; 116(25): 5762-72, 2010 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-20884805

RESUMO

Differentiation of human pluripotent stem cells (hPSCs) into functional cell types is a crucial step in cell therapy. In the present study, we demonstrate that functional CD34(+) progenitor cells can be efficiently produced from human embryonic stem cells (hESCs) and induced pluripotent stem cells (hiPSCs) by combined modulation of 2 signaling pathways. A higher proportion of CD34(+) cells (∼ 20%) could be derived from hPSCs by inhibition of mitogen-activated protein kinase (MAPK) extracellular signal-regulated protein kinase (MEK)/extracellular signal-regulated kinase (ERK) signaling and activation of bone morphogenic protein-4 (BMP4) signaling. hPSC-derived CD34(+) progenitor cells further developed to endothelial and smooth muscle cells with functionality. Moreover, they contributed directly to neovasculogenesis in ischemic mouse hind limbs, thereby resulting in improved blood perfusion and limb salvage. Our results suggest that combined modulation of signaling pathways may be an efficient means of differentiating hPSCs into functional CD34(+) progenitor cells.


Assuntos
Antígenos CD34/metabolismo , Proteína Morfogenética Óssea 4/metabolismo , Diferenciação Celular , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Células-Tronco Pluripotentes Induzidas/metabolismo , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Células-Tronco Pluripotentes/metabolismo , Transdução de Sinais , Animais , Western Blotting , Proteína Morfogenética Óssea 4/genética , Endotélio Vascular/citologia , Endotélio Vascular/metabolismo , MAP Quinases Reguladas por Sinal Extracelular/genética , Citometria de Fluxo , Membro Posterior/irrigação sanguínea , Membro Posterior/metabolismo , Técnicas Imunoenzimáticas , Isquemia/metabolismo , Isquemia/patologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Quinases de Proteína Quinase Ativadas por Mitógeno/genética , Neovascularização Fisiológica , RNA Mensageiro/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa
9.
Proc Natl Acad Sci U S A ; 105(40): 15517-22, 2008 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-18832171

RESUMO

We have used an inhibiting antibody to determine whether preimmune versus antigen-experienced B cells differ in their requisites for BLyS, a cytokine that controls differentiation and survival. Whereas in vivo BLyS inhibition profoundly reduced naïve B cell numbers and primary immune responses, it had a markedly smaller effect on memory B cells and long-lived plasma cells, as well as secondary immune responses. There was heterogeneity within the memory pools, because IgM-bearing memory cells were sensitive to BLyS depletion whereas IgG-bearing memory cells were not, although both were more resistant than naïve cells. There was also heterogeneity within B1 pools, as splenic but not peritoneal B1 cells were diminished by anti-BLyS treatment, yet the number of natural antibody-secreting cells remained constant. Together, these findings show that memory B cells and natural antibody-secreting cells are BLyS-independent and suggest that these pools can be separately manipulated.


Assuntos
Formação de Anticorpos/imunologia , Fator Ativador de Células B/antagonistas & inibidores , Fator Ativador de Células B/fisiologia , Linfócitos B/imunologia , Imunidade Inata/imunologia , Animais , Fator Ativador de Células B/metabolismo , Linfócitos B/citologia , Feminino , Memória Imunológica/imunologia , Camundongos , Camundongos Endogâmicos C57BL
10.
Anal Biochem ; 359(1): 94-105, 2006 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-17007806

RESUMO

In this benchmark study, 26 investigators were asked to characterize the kinetics and affinities of 10 sulfonamide inhibitors binding to the enzyme carbonic anhydrase II using Biacore optical biosensors. A majority of the participants collected data that could be fit to a 1:1 interaction model, but a subset of the data sets obtained from some instruments were of poor quality. The experimental errors in the k(a), k(d), and K(D) parameters determined for each of the compounds averaged 34, 24, and 37%, respectively. As expected, the greatest variation in the reported constants was observed for compounds with exceptionally weak affinity and/or fast association rates. The binding constants determined using the biosensor correlated well with solution-based titration calorimetry measurements. The results of this study provide insight into the challenges, as well as the level of experimental variation, that one would expect to observe when using Biacore technology for small molecule analyses.


Assuntos
Anidrase Carbônica II/química , Anidrase Carbônica II/metabolismo , Inibidores da Anidrase Carbônica/metabolismo , Sulfonamidas/antagonistas & inibidores , Técnicas Biossensoriais , Calorimetria , Inibidores da Anidrase Carbônica/classificação , Variações Dependentes do Observador , Ligação Proteica , Pesquisadores , Sulfonamidas/classificação , Ressonância de Plasmônio de Superfície/instrumentação , Ressonância de Plasmônio de Superfície/normas
11.
Endocrinology ; 147(1): 70-8, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16179414

RESUMO

Vascular endothelial cells (EC) participate in the process of bone formation through the production of factors regulating osteoclast differentiation and function. In this study, we report the selective expression in primary human microvascular EC of Osteostat/TNF superfamily 18, a ligand of the TNF superfamily. Osteostat protein is detectable in human microvascular EC and is highly up-regulated by IFN-alpha and IFN-beta. Moreover, an anti-Osteostat antibody strongly binds to the vascular endothelium in human tissues, demonstrating that the protein is present in the EC layers surrounding blood vessels. Functional in vitro assays were used to define Osteostat involvement in osteoclastogenesis. Both recombinant and membrane-bound Osteostat inhibit differentiation of osteoclasts from monocytic precursor cells. Osteostat suppresses the early stage of osteoclastogenesis via inhibition of macrophage colony-stimulating factor-induced receptor activator of NF-kappaB (RANK) expression in the osteoclast precursor cells. This effect appears to be specific for the differentiation pathway of the osteoclast lineage, because Osteostat does not inhibit lipopolysaccharide-induced RANK expression in monocytes and dendritic cells, or activation-induced RANK expression in T cells. These findings demonstrate that Osteostat is a novel regulator of osteoclast generation and substantiate the major role played by the endothelium in bone physiology.


Assuntos
Endotélio Vascular/fisiologia , Monócitos/fisiologia , Osteoclastos/fisiologia , Fatores de Necrose Tumoral/fisiologia , Fosfatase Ácida/metabolismo , Sequência de Bases , Membrana Celular/fisiologia , Primers do DNA , Glicoproteínas/genética , Humanos , Isoenzimas/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , Fases de Leitura Aberta , Osteoprotegerina , RNA Mensageiro/genética , Receptores Citoplasmáticos e Nucleares/genética , Receptores do Fator de Necrose Tumoral/genética , Proteínas Recombinantes/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fosfatase Ácida Resistente a Tartarato , Fatores de Necrose Tumoral/genética
12.
J Immunol ; 169(9): 4822-30, 2002 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-12391192

RESUMO

IFN-kappa is a recently identified type I IFN that exhibits both structural and functional homology with the other type I IFN subclasses. In this study, we have investigated the effect of IFN-kappa on cells of the innate immune system by comparing cytokine release following treatment of human cells with either IFN-kappa or two recombinant IFN subtypes, IFN-beta and IFN-alpha2a. Although IFN-alpha2a failed to stimulate monocyte cytokine secretion, IFN-kappa, like IFN-beta, induced the release of several cytokines from both monocytes and dendritic cells, without the requirement of a costimulatory signal. IFN-kappa was particularly effective in inhibiting inducible IL-12 release from monocytes. Unlike IFN-beta, IFN-kappa did not induce release of IFN-gamma by PBL. Expression of the IFN-kappa mRNA was observed in resting dendritic cells and monocytes, and it was up-regulated by IFN-gamma stimulation in monocytes, while IFN-beta mRNA was minimally detectable under the same conditions. Monocyte and dendritic cell expression of IFN-kappa was also confirmed in vivo in chronic lesions of psoriasis vulgaris and atopic dermatitis. Finally, biosensor-based binding kinetic analysis revealed that IFN-kappa, like IFN-beta, binds strongly to heparin (K(d): 2.1 nM), suggesting that the cytokine can be retained close to the local site of production. The pattern of cytokines induced by IFN-kappa in monocytes, coupled with the unique induction of IFN-kappa mRNA by IFN-gamma, indicates a potential role for IFN-kappa in the regulation of immune cell functions.


Assuntos
Adjuvantes Imunológicos/fisiologia , Citocinas/biossíntese , Imunidade Celular , Interferon Tipo I/fisiologia , Adulto , Peptídeos Catiônicos Antimicrobianos , Proteínas Sanguíneas/biossíntese , Proteínas Sanguíneas/metabolismo , Proteínas Sanguíneas/fisiologia , Proteínas de Transporte/biossíntese , Proteínas de Transporte/metabolismo , Proteínas de Transporte/fisiologia , Células Cultivadas , Citocinas/metabolismo , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Heparina/metabolismo , Humanos , Imunidade Inata , Inflamação/imunologia , Interferon Tipo I/biossíntese , Interferon Tipo I/metabolismo , Interferon gama/metabolismo , Interleucina-12/antagonistas & inibidores , Interleucina-12/metabolismo , Subpopulações de Linfócitos/imunologia , Subpopulações de Linfócitos/metabolismo , Monócitos/imunologia , Monócitos/metabolismo , Células Mieloides/imunologia , Células Mieloides/metabolismo , Ligação Proteica/imunologia , Pele/imunologia , Pele/patologia
13.
Immunity ; 16(3): 479-92, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11911831

RESUMO

DR3 is a death domain-containing receptor that is upregulated during T cell activation and whose overexpression induces apoptosis and NF-kappaB activation in cell lines. Here we show that an endothelial cell-derived TNF-like factor, TL1A, is a ligand for DR3 and decoy receptor TR6/DcR3 and that its expression is inducible by TNF and IL-1alpha. TL1A induces NF-kappaB activation and apoptosis in DR3-expressing cell lines, while TR6-Fc protein antagonizes these signaling events. Interestingly, in T cells, TL1A acts as a costimulator that increases IL-2 responsiveness and secretion of proinflammatory cytokines both in vitro and in vivo. Our data suggest that interaction of TL1A with DR3 promotes T cell expansion during an immune response, whereas TR6 has an opposing effect.


Assuntos
Glicoproteínas de Membrana , Receptores de Superfície Celular/metabolismo , Receptores do Fator de Necrose Tumoral/metabolismo , Fator de Necrose Tumoral alfa/genética , Sequência de Aminoácidos , Animais , Humanos , Interleucina-1/genética , Interleucina-1/metabolismo , Ligantes , Ativação Linfocitária/imunologia , Camundongos , Dados de Sequência Molecular , Receptores de Superfície Celular/imunologia , Receptores do Fator de Necrose Tumoral/imunologia , Membro 25 de Receptores de Fatores de Necrose Tumoral , Membro 6b de Receptores do Fator de Necrose Tumoral , Alinhamento de Sequência , Linfócitos T/imunologia , Membro 15 da Superfamília de Ligantes de Fatores de Necrose Tumoral , Fator de Necrose Tumoral alfa/metabolismo
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