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1.
Rev Sci Instrum ; 92(4): 043905, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-34243408

RESUMO

We describe a compact and stable setup for detecting the optical second harmonics, in which the incident plane rotates with respect to the sample. The setup is composed of rotating Fresnel rhomb optics and a femtosecond ytterbium-doped fiber laser source operating at the repetition frequency of 10 MHz. The setup including the laser source occupies an area of 1 m2 and is stable so that the intensity fluctuation of the laser harmonics can be less than 0.2% for 4 h. We present the isotropic harmonic signal of a gold mirror of 0.5 pW and demonstrate the integrity and sensitivity of the setup. We also show the polarization-dependent six-fold pattern of the harmonics of a few-layer WSe2, from which we infer the degree of local-field effects. Finally, we describe the extensibility of the setup to investigate the samples in various conditions such as cryogenic, strained, ultrafast non-equilibrium, and high magnetic fields.

2.
Acad Radiol ; 27(4): e55-e63, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31780395

RESUMO

RATIONALE AND OBJECTIVES: We aimed to present a deep learning-based malignancy prediction model (CT-lungNET) that is simpler and faster to use in the diagnosis of small (≤2 cm) pulmonary nodules on nonenhanced chest CT and to preliminarily evaluate its performance and usefulness for human reviewers. MATERIALS AND METHODS: A total of 173 whole nonenhanced chest CT images containing 208 pulmonary nodules (94 malignant and 11 benign nodules) ranging in size from 5 mm to 20 mm were collected. Pathologically confirmed nodules or nodules that remained unchanged for more than 1 year were included, and 30 benign and 30 malignant nodules were randomly assigned into the test set. We designed CT-lungNET to include three convolutional layers followed by two fully-connected layers and compared its diagnostic performance and processing time with those of AlexNET by using the area under the receiver operating curve (AUROC). An observer performance test was conducted involving eight human reviewers of four different groups (medical students, physicians, radiologic residents, and thoracic radiologists) at test 1 and test 2, referring to the CT-lungNET's malignancy prediction rate with pairwise comparison receiver operating curve analysis. RESULTS: CT-lungNET showed an improved AUROC (0.85; 95% confidence interval: 0.74-0.93), compared to that of the AlexNET (0.82; 95% confidence interval: 0.71-0.91). The processing speed per one image slice for CT-lungNET was about 10 times faster than that for AlexNET (0.90 vs. 8.79 seconds). During the observer performance test, the classification performance of nonradiologists was increased with the aid of CTlungNET, (mean AUC improvement: 0.13; range: 0.03-0.19) but not significantly so in the radiologists group (mean AUC improvement: 0.02; range: -0.02 to 0.07). CONCLUSION: CT-lungNET was able to provide better classification results with a significantly shorter amount of processing time as compared to AlexNET in the diagnosis of small pulmonary nodules on nonenhanced chest CT. In this preliminary observer performance test, CT-lungNET may have a role acting as a second reviewer for less experienced reviewers, resulting in enhanced performance in the diagnosis of early lung cancer.


Assuntos
Aprendizado Profundo , Neoplasias Pulmonares , Nódulos Pulmonares Múltiplos , Nódulo Pulmonar Solitário , Humanos , Neoplasias Pulmonares/diagnóstico por imagem , Nódulos Pulmonares Múltiplos/diagnóstico por imagem , Interpretação de Imagem Radiográfica Assistida por Computador , Nódulo Pulmonar Solitário/diagnóstico por imagem , Tomografia Computadorizada por Raios X
3.
Int J Colorectal Dis ; 30(10): 1311-21, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26141090

RESUMO

PURPOSE: We evaluated the current practice of ultra-low anterior resection (uLAR) in patients with lower rectal cancer and compared uLARs using mostly transabdominal approach with or without intersphincteric resection (ISR). METHODS: A total of 624 consecutive lower rectal cancer patients undergoing curative uLAR were prospectively enrolled as ISR+ vs. ISR- groups (329 vs. 295 patients) between 2005 and 2012. The ISR+ group additionally received levator-sphincter reinforcement after distal resection. RESULTS: The circumferential resection margin (CRM) + rate (≤1 mm) was 2.1 % in the two groups. Postoperative ileus occurred more in the ISR- group than in the ISR+ group (p = 0.02). Substantial erectile dysfunction occurred 1.8 times more frequently in the ISR- group than in the ISR+ group (32 vs. 18.1 %; p = 0.01) among male patients at 2 years postoperatively. The urge to defecate volume and maximal tolerance volume, closely correlated with maximal squeezing pressure and/or mean resting pressure, did not differ between patients with and without chemoradiotherapy until 24 months postoperatively. Nevertheless, the urge to defecate volume was lesser in the ISR- group than in the ISR+ group at 24 months postoperatively (p = 0.022). For 301 patients in which >5 years had elapsed postoperatively, the mean 5-year local recurrence rate was 4.3 %, and the 5-year disease-free and overall survival rates were 78.9 and 92 %, respectively, without differences between the two groups. CONCLUSIONS: Compared with uLAR without ISR, the transabdominal ISR with levator-sphincter reinforcement provides a safe resection plane with competent CRM, concurrently reduces substantial complications, and marginally promotes recovery of neorectal function.


Assuntos
Canal Anal/cirurgia , Colo/cirurgia , Neoplasias Retais/cirurgia , Idoso , Anastomose Cirúrgica/efeitos adversos , Intervalo Livre de Doença , Disfunção Erétil/etiologia , Incontinência Fecal/etiologia , Feminino , Humanos , Íleus/etiologia , Masculino , Manometria , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Complicações Pós-Operatórias , Estudos Prospectivos , Neoplasias Retais/patologia , Neoplasias Retais/fisiopatologia , Taxa de Sobrevida , Resultado do Tratamento , Transtornos Urinários/etiologia
4.
Surg Endosc ; 28(9): 2734-44, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24687417

RESUMO

BACKGROUND: Most previous studies of intersphincteric resection (ISR) adopted a two-stage procedure involving abdominal and transanal approaches. We performed completely abdominal ISR via open and a robot-assisted (RA) approaches as treatments for lower rectal cancer (LRC). The RA approach might enable deep dissection and facilitate ISR in patients with restrictive pelvic anatomy. METHODS: A consecutive cohort of 222 LRC patients who underwent completely abdominal ISR (RA ISR, n = 108; open ISR, n = 114) was enrolled prospectively, and their short-term outcomes were evaluated. RESULTS: In a multivariate analysis, ISR was performed more frequently in the RA than in the open group (82.6 vs. 67.9 %, p = 0.008). The number of harvested lymph nodes was >12 in both groups. A positive distal resection margin was not observed in either group, and a positive circumferential resection margin was found in one patient in the RA group. Overall morbidity did not differ between the groups. Moderate to severe sexual dysfunction occurred 2.7-fold more frequently in the open group (p = 0.023) among male patients ≤65 years. Mean Wexner's fecal incontinence scores at postoperative months 6 and 12 were greater in the open group than in the RA group (p < 0.05). CONCLUSIONS: Completely abdominal ISR may be feasible in the treatment of LRC, based on a short-term study. Furthermore, RA ISR had equivalent oncological outcomes and slightly improved functional recovery relative to open ISR.


Assuntos
Canal Anal/cirurgia , Neoplasias Retais/cirurgia , Procedimentos Cirúrgicos Robóticos/métodos , Idoso , Canal Anal/patologia , Estudos de Coortes , Estudos de Viabilidade , Incontinência Fecal/epidemiologia , Feminino , Humanos , Laparoscopia/métodos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Neoplasias Retais/patologia
5.
Int J Colorectal Dis ; 28(4): 493-501, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23053680

RESUMO

PURPOSE: The current study aimed to compare the oncologic outcome and pattern of metastasis after abdominoperineal resection (APR) and low anterior resection (LAR) treating lower rectal cancer. METHODS: A total of 804 patients undergoing curative resection (R0) were enrolled prospectively. The APR and LAR groups (n = 402, respectively) were matched for gender, age, and stage, for a retrospectively comparative analysis. RESULTS: In a multivariate analysis with potential variables, APR itself was not a risk factor for increased local recurrence (LR) or reduced survival (P = 0.243-0.994). Circumferential resection margin (CRM) involvement as an operation-related risk was 1.6-fold more frequent in the APR group and was significantly associated with LR and systemic recurrence (OR, 2.487-4.017; P < 0.01). Circumferential margin positivity (CRM+) was concurrently correlated with advanced stage, larger tumor (long diameter, >4 cm), and longer sagittal midpelvic diameter (>10 cm) in a multivariate analysis (P < 0.001-0.05). The site of metastasis did not differ between the two groups, with the exception of lung metastasis which was more frequent in the APR group (APR vs. LAR: 15.9 vs. 10 %, P = 0.015). In the APR group, CRM+ and the presence of an infiltrating tumor were correlated with disease-free survival (hazard ratio (HR), 1.644 and 1.654, respectively), whereas elevated serum carcinoembryonic antigen and LVI+ were correlated with overall survival (HR, 1.57 and 1.671, respectively), in a multivariate analysis with potential variables (P < 0.05). CONCLUSIONS: When performed with appropriate skill to achieve R0 resection, APR can be used safely without impairing oncological outcome, although sphincter-preserving surgery should remain the preferred option.


Assuntos
Abdome/cirurgia , Procedimentos Cirúrgicos do Sistema Digestório/métodos , Períneo/cirurgia , Neoplasias Retais/cirurgia , Abdome/patologia , Procedimentos Cirúrgicos do Sistema Digestório/efeitos adversos , Intervalo Livre de Doença , Feminino , Humanos , Masculino , Análise por Pareamento , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/patologia , Recidiva Local de Neoplasia/cirurgia , Períneo/patologia , Complicações Pós-Operatórias/etiologia , Resultado do Tratamento , Sistema Urogenital/patologia , Sistema Urogenital/fisiopatologia
6.
Int J Med Robot ; 8(4): 468-75, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22893623

RESUMO

BACKGROUND: Although open resection using a sphincter-saving operation (SSO) remains the standard of care for rectal cancer, few studies have compared open and robot-assisted (RA) SSOs. This study aimed to compare the operative features, functional outcomes, and oncological validity of open and RA SSO for rectal cancer. METHODS: A total of 200 rectal cancer patients undergoing curative SSO were enrolled prospectively. The open and RA groups (n = 100, respectively) were matched for clinical stage and operation type. RESULTS: The mean operation time was significantly longer in the RA group than in the open group (188 vs. 103 min, P < 0.001), but it was significantly reduced in the latter half of the RA patients compared with that in the first half (164 vs. 214 min, P < 0.001). The mean distal resection margin was significantly longer in the RA than in the open group (2.7 vs. 1.9 cm; P = 0.001), but only one patient in either group had positive circumferential resection margin. Bowel peristalsis returned one day earlier in the RA than in the open group (P < 0.001). Postoperative complication rates and anorectal functional outcomes were comparable between the two groups. The operator's physical discomfort, assessed on a visual analog scale, was significantly lower in the RA than in the open group (P < 0.001). CONCLUSIONS: According to this short-term study, the RA SSO showed equivalent oncological safety, functional outcome, and morbidities to open SSO. Although the operation takes longer, the robotic system enables a technically versatile SSO with fine dissection in a limited surgical field.


Assuntos
Procedimentos Cirúrgicos do Sistema Digestório/métodos , Neoplasias Retais/cirurgia , Robótica/métodos , Cirurgia Assistida por Computador/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Canal Anal/fisiopatologia , Canal Anal/cirurgia , Procedimentos Cirúrgicos do Sistema Digestório/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Neoplasias Retais/fisiopatologia , Cirurgia Assistida por Computador/efeitos adversos , Resultado do Tratamento
7.
J Nat Prod ; 74(9): 1908-15, 2011 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-21870831

RESUMO

Five new compounds, 16,23,29-trihydroxy-3-oxo-olean-12-en-28-oic acid (1), 4,23,29-trihydroxy-3,4-seco-olean-12-en-3-oate-28-oic acid (2), 3ß,6ß,23-trihydroxyolean-12-en-28-oic acid 28-O-ß-D-glucopyranoside (3), 3-O-[2,3-di-O-acetyl-α-L-arabinopyranosyl]hederagenin 28-O-α-L-rhamnopyranosyl-(1→4)-ß-D-glucopyranosyl-(1→6)-ß-D-glucopyranoside (4), and 3-O-[3,4-di-O-acetyl-α-L-arabinopyranosyl]hederagenin 28-O-α-L-rhamnopyranosyl-(1→4)-ß-D-glucopyranosyl-(1→6)-ß-D-glucopyranoside (5), as well as 10 known compounds (6-15), were isolated from the stem bark of Kalopanax pictus. Compounds 1-5 and 7-14 inhibited TNFα-induced NF-κB transcriptional activity in HepG2 cells in a dose-dependent manner, with IC50 values ranging from 0.6 to 16.4 µM. Furthermore, the transcriptional inhibitory function of these compounds was confirmed on the basis of decreases in COX-2 and iNOS gene expression in HepG2 cells. The structure-activity relationship of the compounds with respect to anti-inflammatory activity is also discussed.


Assuntos
Anti-Inflamatórios/isolamento & purificação , Anti-Inflamatórios/farmacologia , Kalopanax/química , Saponinas/isolamento & purificação , Saponinas/farmacologia , Triterpenos/isolamento & purificação , Triterpenos/farmacologia , Anti-Inflamatórios/química , Sequência de Bases , Inibidores de Ciclo-Oxigenase 2/química , Inibidores de Ciclo-Oxigenase 2/isolamento & purificação , Inibidores de Ciclo-Oxigenase 2/farmacologia , Células Hep G2 , Humanos , Coreia (Geográfico) , Estrutura Molecular , NF-kappa B/efeitos dos fármacos , Óxido Nítrico Sintase Tipo II/antagonistas & inibidores , Casca de Planta/química , Saponinas/química , Relação Estrutura-Atividade , Triterpenos/química
8.
Mol Carcinog ; 49(3): 259-70, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19908244

RESUMO

To clarify the regulatory mechanism of GW112 gene expression, 5'-flanking region of the human GW112 gene was isolated and characterized in the present study. 5'-RACE analysis showed a single transcription start site, which is located 142 nucleotides upstream of the translation initiation site. Transient transfection studies with serial deletion constructs and close examination of the sequences identified a putative NF kappaB binding sequence between -442 and -430, which could be responsible for efficient expression of the GW112 gene. Indeed, GW112 gene was found to be regulated by NF kappaB signals including overexpressed p65 and I kappaB alpha, IKK inhibitor, and proteasome inhibitor. Binding of NF kappaB to its putative site was confirmed by EMSA and ChIP assays. These results suggest that NF kappaB is an essential regulatory factor for GW112 transcription. Based on this finding, we next confirmed that inhibition of GW112 expression could induce apoptosis in the presence of cytotoxic agent in gastric cancer cells. Furthermore, knocking-down or overexpression of GW112 gene in gastric cancer cells demonstrated that GW112 has an antiapoptotic property against the cytotoxic agents-induced apoptosis. Taken together, these results suggest that GW112 could be an important mediator in NF kappaB-dependent tumorigenesis of digestive tract tissues.


Assuntos
Apoptose , Regulação Neoplásica da Expressão Gênica/fisiologia , Fator Estimulador de Colônias de Granulócitos/genética , NF-kappa B/fisiologia , Neoplasias Gástricas/genética , Western Blotting , Proliferação de Células , Imunoprecipitação da Cromatina , Ensaio de Desvio de Mobilidade Eletroforética , Citometria de Fluxo , Humanos , Immunoblotting , Imunoprecipitação , Luciferases/metabolismo , Regiões Promotoras Genéticas/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patologia , Sítio de Iniciação de Transcrição , Transfecção , Células Tumorais Cultivadas , Regulação para Cima
9.
Obesity (Silver Spring) ; 18(4): 826-32, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19661959

RESUMO

The prevalence of metabolic syndrome (MS) increases with progressing and is potentially associated with changes in adipose-derived cytokines, including adiponectin and retinol-binding protein 4 (RBP4). We aimed to determine the prevalence of MS, and the relationships between these factors and MS in elderly people. A population-based cohort study, the Korean Longitudinal Study on Health and Aging (KLoSHA), was performed on subjects aged > or =65 years by random stratified sampling in 2005-2006 (439 men and 561 women). Anthropometrics, biochemical factors including adiponectin and RBP4 levels, body composition, and abdominal fat by computed tomography (CT) were measured. The prevalence of MS was 61.0% in women and 39.9% in men. After adjustment for age, gender, smoking, alcohol, and exercise status and muscle mass, participants with the lowest quartile of adiponectin had a higher risk for having MS than those with the highest quartile (odds ratio (OR) = 4.12, P < 0.01). Similarly, subjects with the highest quartile of RBP4 showed an increased risk for having MS (OR = 1.73, P < 0.01). When both the lowest adiponectin and the highest RBP4 quartiles were combined, the OR increased to 6.22 compared with the opposite quartiles (i.e., highest adiponectin and lowest RBP4 concentrations). Furthermore, circulating levels of adiponectin and RBP4 were significantly correlated with visceral fat and insulin resistance index. In this study, the increased prevalence of MS in elderly but relatively lean population was associated with low adiponectin and high RBP4 levels. The combination of these factors might predict older subjects at high risk for having MS.


Assuntos
Gordura Abdominal , Adiponectina/sangue , Resistência à Insulina/fisiologia , Síndrome Metabólica/sangue , Proteínas Plasmáticas de Ligação ao Retinol/metabolismo , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Coreia (Geográfico)/epidemiologia , Estudos Longitudinais , Masculino , Síndrome Metabólica/epidemiologia , Prevalência
10.
Endocrinology ; 148(7): 3468-76, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17446187

RESUMO

Although there is evidence that the LIM homeodomain transcription factor, Lhx2, can stimulate transcription of the glycoprotein hormone alpha-subunit gene, the role of Lhx2 in regulating TSH beta-subunit has not been established. In the present studies, the ability of Lhx2 to regulate transcription of the TSH beta-subunit gene was examined. In the thyrotrope-derived TalphaT1 cell line, Lhx2 expression was found to be induced by treatment with either TRH or cAMP, consistent with the possibility that Lhx2 may play a role in mediating the ability of this signaling pathway to stimulate TSH gene expression. Transient, forced overexpression of Lhx2 stimulated activity of a TSH beta-subunit reporter gene. Deletion studies provided evidence that the -177 to -79 region of the TSH beta-subunit promoter was necessary for stimulation of reporter gene activity by Lhx2. A gel mobility shift assay provided the evidence that Lhx2 can bind to this region of DNA. DNase I footprinting studies demonstrated that two distinct regions of the TSHbeta promoter, -118 to -108 and -86 to -68, are protected by Lhx2 from nuclease digestion. These regions contain repeats of the sequence, 5'-(G/T)CAAT(T/A)-3'. Mutation of this sequence, especially in the -86 to -68 region, substantially decreased Lhx2 responsiveness of the TSH beta-subunit reporter gene. In addition, a DNA fragment containing the -177 to -79 region of the TSHbeta promoter was found to confer Lhx2 responsiveness to a minimal promoter. These results provide multiple lines of evidence consistent with a role for Lhx2 in modulating expression of the TSH beta-subunit gene.


Assuntos
Regulação da Expressão Gênica/efeitos dos fármacos , Proteínas de Homeodomínio/genética , Hormônios Hipotalâmicos/farmacologia , Tireotropina Subunidade beta/genética , Fatores de Transcrição/genética , Animais , Sítios de Ligação/genética , Western Blotting , Linhagem Celular , Imunoprecipitação da Cromatina , AMP Cíclico/metabolismo , Desoxirribonuclease I/metabolismo , Relação Dose-Resposta a Droga , Ensaio de Desvio de Mobilidade Eletroforética , Proteínas de Homeodomínio/metabolismo , Proteínas com Homeodomínio LIM , Luciferases/genética , Luciferases/metabolismo , Camundongos , Regiões Promotoras Genéticas/genética , Ligação Proteica , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Transcrição/metabolismo
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