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1.
Nanoscale Adv ; 6(9): 2508-2515, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38694452

RESUMO

Employing copper (Cu) as an anode current collector for metal sulphides is perceived as a general strategy to achieve stable cycle performance in sodium-ion batteries, despite the compatibility of the aluminium current collector with sodium at low voltages. The capacity retention is attributed to the formation of copper sulphide with the slow corrosion of the current collector during cycling which is not ideal. Conventional reports on metal sulphides demonstrate excellent electrochemical performances using excessive carbon coatings/additives, reducing the overall energy density of the cells and making it difficult to understand the underlying side reaction with Cu. In this report, the negative influence of the Cu current collector is demonstrated with in-house synthesised, scalable NiS2 nanoparticles without any carbon coating as opposed to previous works on NiS2 anodes. Ex situ TEM and XPS experiments revealed the formation of Cu2S, further to which various current collectors were employed for NiS2 anode to rule out the parasitic reaction and to understand the true performance of the material. Overall, this study proposes the utilisation of carbon-coated aluminium foil (C/Al) as a suitable current collector for high active material content NiS2 anodes and metal sulphides in general with minimal carbon contents as it remains completely inert during the cycling process. Using a C/Al current collector, the NiS2 anode exhibits stable cycling performance for 5000 cycles at 50 A g-1, maintaining a capacity of 238 mA h g-1 with a capacity decay rate of 8.47 × 10-3% per cycle.

2.
Korean J Gastroenterol ; 82(1): 30-34, 2023 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-37489080

RESUMO

Phlebosclerotic colitis is a rare form of intestinal ischemia. It is caused by calcified peripheral mesenteric veins and a thickened colonic wall. These characteristic findings can be identified on CT and colonoscopy. A 37-year-old female with a history of long-term herbal medicine use presented with acute lower abdominal pain and vomiting of sudden onset. Colonoscopic findings showed dark-blue discolored edematous mucosa and multiple ulcers from the ascending colon to the sigmoid colon. Abdominal CT findings showed diffuse thickening of the colonic wall and calcifications of the peripheral mesenteric veins from the ascending colon to the sigmoid colon. Based on these findings, the patient was diagnosed with phlebosclerotic colitis. We report this rare case of phlebosclerotic colitis in a healthy young female patient with a history of long-term herbal medicine use and include a review of the relevant literature.


Assuntos
Colite Isquêmica , Colite , Adulto , Feminino , Humanos , Colite/diagnóstico , Colite/tratamento farmacológico , Colite Isquêmica/diagnóstico , Colite Isquêmica/etiologia , Colonoscopia , Extratos Vegetais , Tomografia Computadorizada por Raios X
3.
Cardiol Young ; 33(12): 2644-2648, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37127753

RESUMO

OBJECTIVES: To evaluate early- and long-term outcomes of the surgical treatment for coarctation of the aorta based on a new classification system. METHODS: A retrospective clinical review of 111 patients with coarctation of the aorta who underwent surgery (March 2011 to August 2020) was performed. We categorised coarctation of the aorta into type I, with all three head vessels tightly packed; type II, with the left subclavian artery separated from the two other head vessels; and type III, with all three head vessels separated from one another. Each type included subtype a, with a short isthmic portion, and subtype b, with a long isthmic portion. RESULTS: The median patient age and weight at operation were 8 (range, 1-1490) days and 3.2 (range, 1.9-18.5) kg, respectively. Extended end-to-end anastomosis was performed via sternotomy in 54, via thoracotomy in 12, end-to-side anastomosis in 31, autologous main pulmonary artery patch augmentation in 12, and modified end-to-end anastomosis combined with subclavian artery flap aortoplasty in two patients. There was one (0.9%) case of early mortality and 12 (10.8%) cases of post-operative complications. Two (1.8%) late deaths occurred during follow-up. Five (4.5%) patients underwent balloon dilatation and three (2.7%) underwent reoperation for restenosis of coarctation of the aorta. All patients with type Ia (21 patients, 18.9%) underwent extended end-to-end anastomosis via sternotomy or thoracotomy. CONCLUSIONS: According to the early and late outcomes observed in this study, surgical treatment of coarctation of the aorta using the new classification system could be safe and low risk.


Assuntos
Coartação Aórtica , Humanos , Lactente , Coartação Aórtica/complicações , Estudos Retrospectivos , Resultado do Tratamento , Aorta/cirurgia , Aorta Torácica/cirurgia , Anastomose Cirúrgica , Seguimentos , Recidiva
4.
Children (Basel) ; 8(3)2021 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-33802527

RESUMO

Uhl's anomaly is a very rare malformation of unknown cause, characterized by complete or partial absence of the right ventricular myocardium. The cardiac malformation causes progressive right heart failure, increased right-sided cardiac pressure, massive peripheral edema, and ascites. Patients usually present in infancy and rarely survive to adulthood. Previously, diagnosis was made at post-mortem evaluation, but advances in cardiac imaging now permit diagnosis during fetal life. We report a case of Uhl's anomaly in a newborn baby imaged at 23 + 3 weeks of gestation by fetal echocardiography. There was an aneurysmally dilated thin-walled right ventricle with hypertrophy of the right ventricular apical muscles, the tricuspid valve was dysplastic, and the pulmonary valve leaflets were absent.

5.
Korean J Gastroenterol ; 72(3): 146-149, 2018 Sep 25.
Artigo em Coreano | MEDLINE | ID: mdl-30270597

RESUMO

An 88-year-old woman complained of right quadrant abdominal pain and severe edema in both legs. She had a history of pulmonary embolism one month ago. Abdomen CT showed a huge hepatic cyst compressing the intrahepatic portion of the inferior vena cava (IVC). The venogram CT showed multifocal thrombosis in the iliocaval and both lower extremity veins. Percutaneous hepatic cyst drainage was carried out. Fluid analysis presented leukocytosis, which suggested an infected hepatic cyst. To prevent secondary pulmonary thromboembolism, an IVC filter was inserted before catheter drainage for the hepatic cyst. One week later, abdominal pain was relieved. Then, sclerotherapy for the remnant hepatic cyst was performed by ethanol. Follow-up CT showed an increased amount of thrombosis in the iliocaval and left calf vein, but the IVC filter prevented another thromboembolic event successfully. The patient started dabigatran, a new oral anticoagulant, and compression stockings were applied to both legs. After one month, no visible thrombosis in the pelvis or either extremity was detected in abdominal CT. This case suggests that a huge hepatic cyst, especially with infection, should be considered as a possible cause of deep vein thrombosis if no other risk factors for thromboembolism exist.


Assuntos
Cistos/diagnóstico , Hepatopatias/diagnóstico , Trombose Venosa/diagnóstico , Idoso de 80 Anos ou mais , Anticoagulantes/uso terapêutico , Cistos/complicações , Drenagem , Feminino , Humanos , Hepatopatias/complicações , Tomografia Computadorizada por Raios X , Filtros de Veia Cava , Veia Cava Inferior/diagnóstico por imagem , Veia Cava Inferior/patologia , Trombose Venosa/tratamento farmacológico , Trombose Venosa/etiologia
6.
Korean J Gastroenterol ; 72(1): 37-41, 2018 Jul 25.
Artigo em Coreano | MEDLINE | ID: mdl-30049177

RESUMO

Ectopic varices are rare among patients with portal hypertension, especially in the ascending colon. It is difficult to evaluate massive lower gastrointestinal bleeding in patients with liver cirrhosis by colonoscopy due to hemodynamic instability and poor bowel preparation. In Korea, there has only been one case report about ascending colon variceal bleeding, in which hemostasis was performed by venous coil embolization. We report another rare case of ascending colon variceal bleeding in a patient with alcoholic cirrhosis, who was successfully treated via two sessions of N-butyl-2-cyanoacrylate injection through colonoscopy. This case suggests that the careful endoscopic approach and hemostasis with glue injection might be an option for treating massive bleeding in the lower gastrointestinal varix.


Assuntos
Embucrilato/uso terapêutico , Hemorragia Gastrointestinal/prevenção & controle , Cirrose Hepática Alcoólica/patologia , Adesivos Teciduais/uso terapêutico , Colo Ascendente/irrigação sanguínea , Colo Ascendente/diagnóstico por imagem , Colonoscopia , Humanos , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X
7.
Bioelectromagnetics ; 33(7): 604-11, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22549623

RESUMO

The aim of this study was to determine whether the exposure to either single or multiple radio-frequency (RF) radiation frequencies could induce oxidative stress in cell cultures. Exposures of human MCF10A mammary epithelial cells to either a single frequency (837 MHz alone or 1950 MHz alone) or multiple frequencies (837 and 1950 MHz) were conducted at specific absorption rate (SAR) values of 4 W/kg for 2 h. During the exposure period, the temperature in the exposure chamber was maintained isothermally. Intracellular levels of reactive oxygen species (ROS), the antioxidant enzyme activity of superoxide dismutase (SOD), and the ratio of reduced/oxidized glutathione (GSH/GSSG) showed no statistically significant alterations as the result of either single or multiple RF radiation exposures. In contrast, ionizing radiation-exposed cells, used as a positive control, showed evident changes in all measured biological endpoints. These results indicate that single or multiple RF radiation exposure did not elicit oxidative stress in MCF10A cells under our exposure conditions.


Assuntos
Estresse Oxidativo/efeitos da radiação , Ondas de Rádio/efeitos adversos , Linhagem Celular Tumoral , Dissulfeto de Glutationa/metabolismo , Humanos , Espécies Reativas de Oxigênio/metabolismo
8.
J Radiat Res ; 53(2): 176-83, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22510589

RESUMO

Exposure to environmental stressors can be measured by monitoring the cellular stress response in target cells. Here, we used the cellular stress response to investigate whether single or combined radio frequency (RF) radiation could induce stress response in human cells. Cellular stress responses in MCF10A human breast epithelial cells were characterized after exposure to 4 h of RF radiation [code division multiple access (CDMA) or CDMA plus wideband CDMA (WCDMA)] or 2 h RF radiation on 3 consecutive days. Specific absorption rate (SAR) was 4.0 W/kg for CDMA signal alone exposure and 2.0 W/kg each, 4.0 W/kg in total for combined CDMA plus WCDMA signals. Expression levels and phosphorylation states of specific heat shock proteins (HSPs) and mitogen-activated protein kinases (MAPKs) were analyzed by Western blot. It was found that HSP27 and ERK1/2 phosphorylations are the most sensitive markers of the stress response in MCF10A cells exposed to heat shock or ionizing radiation. Using these markers, we demonstrated that neither one-time nor repeated single (CDMA alone) or combined (CDMA plus WCDMA) RF radiation exposure significantly altered HSP27 and ERK1/2 phosphorylations in MCF10A cells (p > 0.05). The lack of a statistically significant alteration in HSP27 and ERK1/2 phosphorylations suggests that single or combined RF radiation exposure did not elicit activation of HSP27 and ERK1/2 in MCF10A cells.


Assuntos
Mama/fisiologia , Mama/efeitos da radiação , Proteínas de Choque Térmico/metabolismo , Micro-Ondas , Ondas de Rádio , Estresse Fisiológico/fisiologia , Estresse Fisiológico/efeitos da radiação , Linhagem Celular , Relação Dose-Resposta a Droga , Feminino , Humanos , Doses de Radiação
9.
Bioelectromagnetics ; 33(4): 356-64, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22012556

RESUMO

Wireless mobile phones and other telecommunication devices are used extensively in daily life. We therefore examined the effects of combined exposure to radiofrequency electromagnetic fields (RF-EMF) on rat testicular function, specifically with respect to sensitive processes such as spermatogenesis. Male rats were exposed to single code division multiple access (CDMA) and wideband code division multiple access (WCDMA) RF signals for 12 weeks. The RF exposure schedule comprised 45 min/day, 5 days/week for a total of 12 weeks. The whole-body average specific absorption rate (SAR) of CDMA and WCDMA was 2.0 W/kg each or 4.0 W/kg in total. We then investigated the correlates of testicular function such as sperm count in the cauda epididymis, testosterone concentration in the blood serum, malondialdehyde concentrations in the testes and epididymis, frequency of spermatogenesis stages, and appearance of apoptotic cells in the testes. We also immunoblotted for p53, bcl2, GADD45, cyclin G, and HSP70 in the testes of sham- and combined RF-exposed animals. Based on the results, we concluded that simultaneous exposure to CDMA and WCDMA RF-EMFs at 4.0 W/kg SAR did not have any observable adverse effects on rat spermatogenesis.


Assuntos
Campos Eletromagnéticos/efeitos adversos , Ondas de Rádio/efeitos adversos , Testículo/fisiologia , Testículo/efeitos da radiação , Animais , Apoptose/efeitos da radiação , Temperatura Corporal/efeitos da radiação , Ciclina G/metabolismo , Dano ao DNA , Epididimo/metabolismo , Epididimo/efeitos da radiação , Proteínas de Choque Térmico HSP70/metabolismo , Masculino , Malondialdeído/metabolismo , Tamanho do Órgão/efeitos da radiação , Estresse Oxidativo/efeitos da radiação , Ratos , Ratos Sprague-Dawley , Contagem de Espermatozoides , Espermatogênese/efeitos da radiação , Testículo/citologia , Testículo/metabolismo , Testosterona/sangue , Fatores de Tempo
10.
Bioelectromagnetics ; 32(3): 169-78, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21365661

RESUMO

The aim of this study was to investigate whether single or combined radio frequency (RF) radiation exposure has effects on the cell cycle and its regulatory proteins. Exposure of MCF7 cells to either single (837 MHz) or combined (837 and 1950 MHz) RF radiation was conducted at specific absorption rate values of 4 W/kg for 1 h. During the exposure period, the chamber was made isothermal by circulating water through the cavity. After RF radiation exposure, DNA synthesis rate and cell cycle distribution were assessed. The levels of cell cycle regulatory proteins, p53, p21, cyclins, and cyclin-dependent kinases were also examined. The positive control group was exposed to 0.5 and 4 Gy doses of ionizing radiation (IR) and showed changes in DNA synthesis and cell cycle distribution. The levels of p53, p21, cyclin A, cyclin B1, and cyclin D1 were also affected by IR exposure. In contrast to the IR-exposed group, neither the single RF radiation- nor the combined RF radiation-exposed group elicited alterations in DNA synthesis, cell cycle distribution, and levels of cell cycle regulatory proteins. These results indicate that neither single nor combined RF radiation affect cell cycle progression.


Assuntos
Proteínas de Ciclo Celular/metabolismo , Ciclo Celular/efeitos da radiação , Ondas de Rádio , Bromodesoxiuridina/metabolismo , Linhagem Celular Tumoral , DNA/biossíntese , Humanos
11.
Bioelectromagnetics ; 32(6): 485-92, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21437920

RESUMO

There are public concerns regarding possible carcinogenic or cancer-promoting effects of radiofrequency electromagnetic fields (RF-EMFs) because of the extensive use of wireless mobile phones and other telecommunication devices in daily life. However, so far it is unclear if non-thermal exposure of single EMF exposure in animal studies has a direct influence on carcinogenesis. Here, carcinogenic effects of combined signal RF-EMFs on AKR/J mice, which were used for the lymphoma animal model, were investigated. Six-week-old AKR/J mice were simultaneously exposed to two types of RF signals: single code division multiple access (CDMA) and wideband code division multiple access (WCDMA). AKR/J mice were exposed to combined RF-EMFs for 45 min/day, 5 days/week, for a total of 42 weeks. The whole-body average specific absorption rate (SAR) of CDMA and WCDMA fields was 2.0 W/kg each, 4.0 W/kg in total. When we examined final survival, lymphoma incidence, and splenomegaly incidence, no differences were found between sham- and RF-exposed mice. However, occurrence of metastasis infiltration to the brain in lymphoma-bearing mice was significantly different in RF-exposed mice when compared to sham-exposed mice, even though no consistent correlation (increase or decrease) was observed between male and female mice. However, infiltration occurrence to liver, lung, and spleen was not different between the groups. From the results, we suggested that simultaneous exposure to CDMA and WCDMA RF-EMFs did not affect lymphoma development in AKR/J mice.


Assuntos
Linfoma/etiologia , Ondas de Rádio/efeitos adversos , Animais , Neoplasias Encefálicas/secundário , Feminino , Neoplasias Hepáticas/secundário , Neoplasias Pulmonares/secundário , Linfoma/patologia , Masculino , Camundongos , Camundongos Endogâmicos AKR , Invasividade Neoplásica , Esplenomegalia
12.
Bioelectromagnetics ; 31(7): 528-34, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20607737

RESUMO

We examined the histological changes by radiofrequency (RF) fields on rat testis, specifically with respect to sensitive processes such as spermatogenesis. Male rats were exposed to 848.5 MHz RF for 12 weeks. The RF exposure schedule consisted of two 45-min RF exposure periods, separated by a 15-min interval. The whole-body average specific absorption rate (SAR) of RF was 2.0 W/kg. We then investigated correlates of testicular function such as sperm counts in the cauda epididymis, malondialdehyde concentrations in the testes and epididymis, frequency of spermatogenesis stages, germ cell counts, and appearance of apoptotic cells in the testes. We also performed p53, bcl-2, caspase 3, p21, and PARP immunoblotting of the testes in sham- and RF-exposed animals. Based on these results, we concluded that subchronic exposure to 848.5 MHz with 2.0 W/kg SAR RF did not have any observable adverse effects on rat spermatogenesis.


Assuntos
Telefone Celular , Ondas de Rádio/efeitos adversos , Testículo/citologia , Testículo/efeitos da radiação , Animais , Apoptose/efeitos da radiação , Temperatura Corporal/efeitos da radiação , Peso Corporal/efeitos da radiação , Campos Eletromagnéticos/efeitos adversos , Epididimo/citologia , Epididimo/metabolismo , Epididimo/efeitos da radiação , Masculino , Malondialdeído/metabolismo , Tamanho do Órgão/efeitos da radiação , Doses de Radiação , Ratos , Ratos Sprague-Dawley , Contagem de Espermatozoides , Espermatogênese/efeitos da radiação , Espermatozoides/citologia , Espermatozoides/metabolismo , Espermatozoides/efeitos da radiação , Testículo/metabolismo , Testículo/fisiologia
13.
Genes Genet Syst ; 81(5): 333-9, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17159294

RESUMO

The MCJ gene is a member of the DNAJ family, and its transcriptional event is controlled by methylation of the CpG island. In our study, we found LTR33 and LTR7 elements provided an alternative transcript within the MCJ gene. To detect different expression patterns between the originally reported MCJ transcript and the LTR-related transcript, we performed a RT-PCR approach using various human tissues and cancer cells. The original MCJ transcript was detected in human tissues and cancer cells, whereas the LTR-related transcript was only revealed in some cancer cells (HCT106, MCF-3, TE-1, Hela, and CCHM). We also performed a PCR analysis to compare the insertion lineage of the LTR elements with the genomic DNAs of primates, indicating that those LTR33 and LTR7 elements of HERV-H have been integrated into the primate genome at different times. Taken together, we suggest that HERV-related elements trigger transcriptome diversification during primate evolution.


Assuntos
Retrovirus Endógenos/genética , Proteínas de Choque Térmico HSP40/genética , RNA Mensageiro/genética , Sequência de Bases , Células HL-60 , Proteínas de Choque Térmico HSP40/biossíntese , Células HeLa , Humanos , Células Jurkat , Dados de Sequência Molecular , Células U937
14.
Mt Sinai J Med ; 73(5): 795-801, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17008941

RESUMO

BACKGROUND: Only a few studies comparing percutaneous endoscopic discectomy and open discectomy have been reported in the literature. The purpose of this study was to compare the radiographic changes in patients treated with percutaneous endoscopic lumbar discectomy (PELD) with those of patients treated with open lumbar microdiscectomy (OLM). METHODS: A total of 30 patients who underwent PELD with a minimum three years of follow-up were randomly selected. To compare with the PELD group, 30 patients who underwent OLM during the same period were also randomly selected according to sex, age, and disc level. The clinical outcomes were evaluated by the Macnab criteria. Statistical analysis was performed using independent sample t-test, paired sample t-test, chi-square test, Fisher's exact test, and analysis of variance (ANOVA). RESULTS: The successful clinical outcomes were 96.7% in the PELD group and 93.3% in the OLM group. Among the various radiological parameters, changes of disc height (1.41 +/- 1.19 mm in the PELD group and 2.29 +/- 2.12 mm in the OLM group, p=0.024) and foraminal height (1.26 +/- 0.91 mm in the PELD group and 1.85 +/- 0.92 mm in the OLM group, p=0.017) were significantly different between the two groups. CONCLUSIONS: Although the clinical outcomes were similarly satisfactory in both groups, PELD is a less invasive procedure than open microdiscectomy in s elected cases.


Assuntos
Discotomia Percutânea , Endoscopia , Disco Intervertebral/cirurgia , Região Lombossacral/cirurgia , Resultado do Tratamento , Adulto , Idoso , Feminino , Humanos , Disco Intervertebral/diagnóstico por imagem , Região Lombossacral/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Minimamente Invasivos , Estudos Prospectivos , Radiografia , Ensaios Clínicos Controlados Aleatórios como Assunto , Avaliação da Tecnologia Biomédica
15.
J Neurochem ; 95(1): 1-8, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16181408

RESUMO

The proper regulation of temporal and spatial expression of the axon guidance cues and their receptors is critical for the normal wiring of nervous system during development. Netrins, a family of secreted guidance cues, are involved in the midline crossing of spinal commissural axons and in the guidance of cortical efferents. Axons normally lose the responsiveness to their attractants when they arrive at their targets, where the attractant is produced. However the molecular mechanism is still unknown. We investigated the molecular mechanism of down-regulation of netrin-1 signaling in the embryonic cortical neurons. Netrin-1 induced the ubiquitination and proteolytic cleavage of Deleted in Colorectal Cancer (DCC), a transmembrane receptor for netrin, in dissociated cortical neurons. A dramatic decrease of DCC level particularly on the cell surface was also observed after netrin-1 stimulation. Specific ubiquitin-proteasome inhibitors prevented the netrin-induced DCC cleavage and decrease of cell surface DCC. We suggest that the ligand-mediated down-regulation of DCC might participate in the loss of netrin-responsiveness in the developing nervous system.


Assuntos
Moléculas de Adesão Celular/metabolismo , Córtex Cerebral/embriologia , Regulação para Baixo , Fatores de Crescimento Neural/farmacologia , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Proteínas Supressoras de Tumor/farmacologia , Ubiquitina/metabolismo , Animais , Moléculas de Adesão Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Células Cultivadas , Receptor DCC , Embrião de Mamíferos/citologia , Embrião de Mamíferos/metabolismo , Humanos , Netrina-1 , Neurônios/metabolismo , Peptídeo Hidrolases/metabolismo , Ratos , Ratos Sprague-Dawley , Receptores de Superfície Celular , Proteínas Supressoras de Tumor/efeitos dos fármacos
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