Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 22
Filtrar
Mais filtros








Base de dados
Intervalo de ano de publicação
1.
Eur J Surg Oncol ; 50(11): 108614, 2024 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-39213694

RESUMO

BACKGROUND: This study aimed to elucidate the clinical value of combined pancreaticoduodenectomy (PD) for advanced gallbladder cancer according to the mode of cancer spread in the pancreaticoduodenal region. METHODS: Patients who underwent combined PD for advanced gallbladder cancer were retrospectively reviewed. The mode of cancer spread in the pancreaticoduodenal region was defined as involvement of peripancreatic organs/structures alone, peripancreatic nodal metastasis alone, or both. Surgical outcomes were compared among these modes of spread. RESULTS: Fifty-seven patients were included. Rates of severe morbidity and mortality were 52.6% and 3.5%, respectively. The mode of cancer spread was involvement of peripancreatic organs/structures alone in 16 patients, peripancreatic nodal metastasis alone in 17, and both in 24; R0 resection rates differed significantly among the groups (87.5% vs. 94.1% vs. 37.5%; p < 0.001). Overall survival (OS) was significantly worse in patients with both modes of spread (5-year OS, 8.3%) than in those with involvement of peripancreatic organs/structures alone (5-year OS, 37.9%; p < 0.001) and those with peripancreatic nodal metastasis alone (5-year OS, 29.4%; p = 0.011). OS was similar between pM0 patients with both modes of spread and pM1 patients (5-year OS, 16.7% vs. 8.7%; p = 0.605). Multivariate analysis identified mode of cancer spread as an independent prognostic factor (p = 0.006). CONCLUSIONS: Combined PD could be oncologically justified for advanced gallbladder cancer with involvement of peripancreatic organs/structures alone or peripancreatic nodal metastasis alone in the pancreaticoduodenal region. This procedure would not be indicated in patients with both modes of spread.

2.
Anticancer Res ; 44(5): 1915-1924, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38677747

RESUMO

BACKGROUND/AIM: NAD(P)H dehydrogenase [quinone] 1 (NQO1), an antioxidant enzyme, confers resistance to anticancer agents. NQO1 C609T is a single-nucleotide polymorphism associated with reduced protein expression in the non-neoplastic esophageal squamous epithelium (ESE). This study aimed to investigate immunohistochemical NQO1 expression in non-neoplastic ESE and to elucidate its prognostic significance in patients with esophageal squamous cell carcinoma (ESCC) undergoing neoadjuvant therapy followed by esophagectomy. MATERIALS AND METHODS: NQO1 expression in non-neoplastic ESE was determined in surgical specimens from 83 patients with ESCC using immunohistochemistry. The association between NQO1 expression and clinicopathological factors, and the prognostic significance of NQO1 expression for relapse-free survival (RFS) were statistically evaluated. RESULTS: Patients with complete loss or weak NQO1 expression and patients with moderate or strong NQO1 expression were classified into the NQO1-negative (n=29) and NQO1-positive (n=54) groups, respectively. The downstaging of T classification status after neoadjuvant therapy was significantly more frequent in the NQO1-negative group than in the NQO1-positive group (59% vs. 33%; p=0.036). The NQO1-negative group had significantly more favorable RFS than the NQO1-positive group (p=0.035). Multivariate survival analysis demonstrated that NQO1 negative expression had a favorable prognostic impact on RFS (HR=0.332; 95%CI=0.136-0.812; p=0.016). CONCLUSION: Immunohistochemical evaluation of NQO1 expression in non-neoplastic ESE has clinical utility for predicting patient prognosis after neoadjuvant therapy followed by esophagectomy and might be helpful for selecting candidates for adjuvant therapy to treat ESCC.


Assuntos
Carcinoma de Células Escamosas , Neoplasias Esofágicas , NAD(P)H Desidrogenase (Quinona) , Humanos , NAD(P)H Desidrogenase (Quinona)/genética , NAD(P)H Desidrogenase (Quinona)/metabolismo , Neoplasias Esofágicas/patologia , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/metabolismo , Neoplasias Esofágicas/mortalidade , Feminino , Masculino , Pessoa de Meia-Idade , Prognóstico , Idoso , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/genética , Esofagectomia , Terapia Neoadjuvante , Biomarcadores Tumorais/metabolismo , Biomarcadores Tumorais/genética , Carcinoma de Células Escamosas do Esôfago/patologia , Carcinoma de Células Escamosas do Esôfago/genética , Carcinoma de Células Escamosas do Esôfago/metabolismo , Adulto , Imuno-Histoquímica , Intervalo Livre de Doença , Idoso de 80 Anos ou mais
3.
Transplant Proc ; 56(3): 660-666, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38519268

RESUMO

OBJECTIVES: De novo malignancy (DNM) is a major cause of death in long-term recipients of liver transplantation (LT). We herein report our experience with DNM after living-donor LT (LDLT). PATIENTS AND METHODS: A total of 111 LDLT procedures were performed in our institute from 1999 to 2022. Among them, 70 adult (>13 years old) LDLT recipients who survived for more than 1 year were included in this study. RESULTS: During a median follow-up of 146 (range, 12-285) months, 7 out of 70 recipients developed 8 DNMs, including lung cancer in 4, post-transplant lymphoproliferative disease in 3, and skin cancer in 1. One patient developed metachronal skin cancer and post-transplant lymphoproliferative disease. The pre-LT smoking history rate in patients with DNM was higher than in patients without DNM (P = .004). The survival time after DNM was 6 (1-166) months. Only 2 patients underwent R0 resection. DNM did not recur during follow-up. Other patients who underwent R1 resection and/or chemotherapy and/or radiotherapy all died due to DNMs during the follow-up. The cumulative DNM incidence was 3.5% at 10 years and 18.4% at 20 years after LDLT. The cumulative survival rate in patients with DNM was significantly worse than that in patients without DNM after LDLT (P = .049). CONCLUSION: The survival rate of patients with DNM was lower than that of those without DNM. A pre-LT smoking history is a risk factor for DNM. R0 resection is effective for improving the prognosis of patients with DNM. Regular cancer screening is important for detecting DNM early after LDLT.


Assuntos
Transplante de Fígado , Doadores Vivos , Humanos , Transplante de Fígado/efeitos adversos , Pessoa de Meia-Idade , Masculino , Adulto , Feminino , Adulto Jovem , Neoplasias/cirurgia , Estudos Retrospectivos , Fatores de Risco , Adolescente , Idoso , Complicações Pós-Operatórias/epidemiologia
4.
Gan To Kagaku Ryoho ; 51(1): 72-74, 2024 Jan.
Artigo em Japonês | MEDLINE | ID: mdl-38247096

RESUMO

The patient was a 61-year-old man with a diagnosis of carcinoma of the pancreatic head. Abdominal computed tomography( CT)showed no distant metastasis, and he underwent subtotal stomach-preserving pancreatoduodenectomy. Immediately after surgery, he received liver perfusion chemotherapy with 5-fluorouracil followed by systemic gemcitabine. Eighteen months after surgery, CT revealed liver metastasis in the S6 segment, and partial hepatectomy was performed. The pathological diagnosis was liver metastasis of pancreatic cancer. Postoperatively, the patient was treated with gemcitabine and S-1 therapy for 1 year and then switched to S-1 monotherapy for about 6 months. Four years after the initial surgery, CT showed 2 metastases in the right lung. After 2 months of S-1 monotherapy, wedge resection of the upper and lower lobes of the right lung was performed. Gemcitabine and nab-paclitaxel therapy were administered, after the metastasectomy, but pleural dissemination appeared on CT 5 years after the initial surgery. Modified FOLFIRINOX therapy was started and continued for 8 months, but CT revealed further disseminated lesions in the diaphragm. Palliative irradiation was provided, but the disease gradually progressed. After multidisciplinary treatment, the patient survived for 6 years and 3 months after the initial surgery.


Assuntos
Adenocarcinoma , Neoplasias Hepáticas , Metastasectomia , Neoplasias Pancreáticas , Masculino , Humanos , Pessoa de Meia-Idade , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Gencitabina , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/cirurgia , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/cirurgia
5.
World J Oncol ; 14(5): 430-437, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37869237

RESUMO

Background: Ceramide and sphingosine-1-phosphate (S1P) play opposing roles in cell death and survival, and maintain a dynamic balance called the sphingolipid rheostat. Glucosylceramide is a substrate to generate ceramide but its effect on breast cancer by oral administration was never tested. The purpose of this study was to reveal the anticancer activity of glucosylceramide and its potential as a new therapeutic agent in breast cancer. Methods: E0771 cells were inoculated into the breast tissue of female C57BL/6NJcl mice. Glucosylceramide was administered orally to the mice for nine consecutive days. The concentrations of sphingolipid mediators including ceramide, glucosylceramide, and S1P in tumor tissues and serum were determined by mass spectrometry. Results: Oral administration of glucosylceramide significantly suppressed E0771 tumor growth compared with the control group (P = 0.006). There were no significant differences in the serum concentrations of sphingolipid mediators including ceramide and S1P between the mice treated with glucosylceramide and control-treated mice. The ceramide concentration was significantly lower in tumor tissues (P = 0.026), and the S1P concentration was significantly higher than that in paired non-tumor tissues (P = 0.009). The S1P concentration in tumor tissues was significantly lower in mice treated with glucosylceramide than in control-treated mice (P = 0.001). The ceramide-to-S1P concentration ratio in tumor tissues was significantly higher in mice treated with glucosylceramide than in control-treated mice (P = 0.034). Conclusions: Breast tumors could enhance their survival by increasing S1P conversion from ceramide. Oral administration of glucosylceramide suppressed tumor growth by affecting the ceramide/S1P balance. Oral administration of glucosylceramide is a promising basis for a new therapeutic approach.

6.
Eur J Surg Oncol ; 49(12): 107122, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37897834

RESUMO

BACKGROUND: This study aimed to evaluate the adequate extent of regional lymphadenectomy according to tumor location and the impact of number-based nodal classification on survival in patients with non-ampullary duodenal adenocarcinoma (NADAC). METHODS: A total of 85 patients with NADAC who underwent surgery were enrolled. The frequency of metastasis was calculated for each node group in the respective tumor locations for 63 patients who underwent lymphadenectomy for pT2-pT4 tumor. RESULTS: The frequency of metastasis in the pancreaticoduodenal (nos. 13 and 17) and superior mesenteric artery (no. 14) nodes was high (16.7 %-52.3 %) regardless of tumor location. Metastasis in the perigastric (nos. 3 and 4d) and right celiac artery (no. 9) nodes was not uncommon (14.3 %-22.2 %) for tumors in the first portion. The frequency of metastasis in the pyloric (nos. 5 and 6) and the other peripancreaticoduodenal (nos. 8 and 12) nodes varied depending on tumor location but could not be ignored for staging. When these nodes were classified as regional nodes, the 5-year survival in patients with pN0, pN1 (1-2 positive nodes), and pN2 (≥3 positive nodes) were 82.9 %, 51.7 %, and 19.2 %, respectively (p < 0.001). pN classification independently predicted survival (pN1, p = 0.022; pN2, p < 0.001). CONCLUSIONS: Nos. 5, 6, 8, 12, 13, 14, and 17 nodes in all advanced NADAC and nos. 3, 4d, and 9 nodes in advanced NADAC in the first portion should be considered as regional nodes for accurate staging. The number-based nodal classification allows good patients' prognostic stratification.


Assuntos
Adenocarcinoma , Neoplasias Duodenais , Humanos , Estadiamento de Neoplasias , Excisão de Linfonodo , Adenocarcinoma/cirurgia , Adenocarcinoma/patologia , Prognóstico , Neoplasias Duodenais/cirurgia , Neoplasias Duodenais/patologia , Linfonodos/cirurgia , Linfonodos/patologia
7.
Anticancer Res ; 43(9): 3969-3977, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37648331

RESUMO

BACKGROUND/AIM: Sphingosine-1-phosphate (S1P) is a pleiotropic, bioactive, lipid mediator, produced by sphingosine kinase 1 (SphK1). In this study, we evaluated the expression of phosphorylated SphK1 (pSphK1) in patients with pancreatic ductal adenocarcinoma (PDAC) and investigated its clinical significance. MATERIALS AND METHODS: A total of 111 patients who underwent curative-intent resection for PDAC were enrolled. We investigated pSphK1 (Ser-225) expression in surgically resected specimens of PDAC using immunohistochemistry. The patients were divided into two groups according to pSphK1 immunoreactive expression: a pSphK1-high group (n=63) and a pSphK1-low group (n=48). RESULTS: Logistic regression analyses revealed that lymphatic invasion (p=0.007) was a significantly independent factor associated with high pSphK1 immunoreactive expression. The pSphK1-high group showed significantly worse disease-specific survival (DSS) than the pSphK1-low group (5-year DSS rate, 19.6% vs. 58.7%; p=0.001). High pSphK1 immunoreactive expression (hazard ratio=2.547; 95% confidence interval= 1.434-4.527; p=0.001) was an independent prognostic factor for DSS. CONCLUSION: High pSphK1 expression is independently associated with lymphatic invasion and unfavorable prognosis in PDAC patients. Thus, the SphK1-S1P axis may be important in mechanisms of tumor progression, such as lymphatic invasion, in PDAC patients.


Assuntos
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Humanos , Relevância Clínica , Neoplasias Pancreáticas/cirurgia , Carcinoma Ductal Pancreático/cirurgia , Neoplasias Pancreáticas
8.
Gan To Kagaku Ryoho ; 50(2): 227-229, 2023 Feb.
Artigo em Japonês | MEDLINE | ID: mdl-36807180

RESUMO

We report a case of intrahepatic cholangiocarcinoma(ICC)with lymph node metastases in which long-term survival was achieved after surgery followed by chemotherapy. A 69-year-old man underwent left hepatectomy, extrahepatic bile duct resection, and lymph node dissection for ICC located mainly in segment 4 of the liver with enlarged lymph nodes in the hepatoduodenal ligament. The histopathologically confirmed diagnosis was ICC(T2N1M0, Stage ⅣA)with 3 positive lymph nodes(No. 12a1, No. 12p1, and No. 12p2). He received chemotherapy with gemcitabine(GEM)plus cisplatin(CDDP)for 9 months, followed by GEM monotherapy for 4 months, and then S-1 monotherapy was started. A right lung nodule was detected 12 months after the initiation of S-1 monotherapy. He received GEM plus S-1 therapy for 28 months, followed by S-1 monotherapy, leading to disappearance of the lung nodule. He remains alive and well without disease 78 months after surgery. Our experience in this case suggests that radical resection followed by chemotherapy may provide a survival benefit in selected patients who have ICC with nodal disease.


Assuntos
Neoplasias dos Ductos Biliares , Colangiocarcinoma , Masculino , Humanos , Idoso , Ductos Biliares Intra-Hepáticos/patologia , Metástase Linfática/patologia , Colangiocarcinoma/cirurgia , Excisão de Linfonodo , Hepatectomia , Neoplasias dos Ductos Biliares/cirurgia , Sobreviventes
9.
Eur J Surg Oncol ; 49(2): 399-409, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36404251

RESUMO

INTRODUCTION: This study aimed to evaluate the association between the preoperative Controlling Nutritional Status (CONUT) score, survival outcomes, and recurrence pattern in patients with resectable biliary tract cancer (BTC). METHODS: A total of 224 BTC patients (gallbladder, n = 69; intrahepatic bile ducts, n = 26; perihilar bile ducts, n = 72; distal bile duct, n = 57) who underwent surgery with curative intent were enrolled. The best cutoff point of the preoperative CONUT score in discriminating survival was determined using χ2 scores. The sites of recurrence were subclassified as locoregional or distant. RESULTS: Patients were subdivided into the CONUT-low (score ≤ 3, n = 156) and the CONUT-high (score > 3; n = 68) groups. In-hospital mortality occurred more frequently in the CONUT-high group than in the CONUT-low group (7.4% vs. 1.3%; p = 0.028). A high preoperative CONUT score was independently associated with worse overall survival (hazard ratio [HR] 1.906, p = 0.001), worse disease-specific survival (HR 1.840, p = 0.006), and worse recurrence-free survival (HR 1.680, p = 0.005). Recurrence developed in 110 (49.1%) patients. A high preoperative CONUT score was independently associated with a higher risk of distant recurrence (HR 2.245, p = 0.001), but not locoregional recurrence. The incidences of distant recurrence at 5 years were 55.4% and 34.2% in the CONUT-high and CONUT-low groups, respectively (p = 0.001). CONCLUSIONS: The preoperative CONUT score independently predicts survival outcomes and may serve as a surrogate marker of aggressive systemic disease recurrence in patients with resectable BTC.


Assuntos
Neoplasias do Sistema Biliar , Estado Nutricional , Humanos , Biomarcadores , Modelos de Riscos Proporcionais , Ductos Biliares Intra-Hepáticos , Estudos Retrospectivos , Prognóstico
10.
Gan To Kagaku Ryoho ; 50(13): 1753-1755, 2023 Dec.
Artigo em Japonês | MEDLINE | ID: mdl-38303196

RESUMO

A 66-year-old man was referred to our hospital with fever and abdominal pain. CT showed a mass in the intrapancreatic bile duct but no wall thickness in the perihilar bile ducts. Neither regional lymphadenopathy nor distant metastasis was observed. Biliary cytology showed adenocarcinoma. The diagnosis was distal cholangiocarcinoma, and pancreatoduodenectomy was performed. Intraoperative frozen section examination of the ductal resection margins at the right and left hepatic ducts was positive for carcinoma in situ, and the operation ultimately completed with R1 resection. Histological examination confirmed a diagnosis of cholangiocarcinoma with superficial spread and a single positive lymph node. Adjuvant chemotherapy with S-1 was administered for 1 year. Anastomotic recurrence at the hepaticojejunostomy was found 5 years after resection; biopsy specimens revealed adenocarcinoma. Thereafter, S-1 chemotherapy was resumed, and the patient remains alive and well 9 years and 1 month after resection.


Assuntos
Adenocarcinoma , Neoplasias dos Ductos Biliares , Carcinoma in Situ , Colangiocarcinoma , Masculino , Humanos , Idoso , Metástase Linfática , Margens de Excisão , Colangiocarcinoma/tratamento farmacológico , Colangiocarcinoma/cirurgia , Colangiocarcinoma/patologia , Ductos Biliares Intra-Hepáticos/patologia , Adenocarcinoma/cirurgia , Carcinoma in Situ/cirurgia , Hepatectomia , Neoplasias dos Ductos Biliares/tratamento farmacológico , Neoplasias dos Ductos Biliares/cirurgia , Neoplasias dos Ductos Biliares/patologia , Sobreviventes
11.
Gan To Kagaku Ryoho ; 50(13): 1872-1874, 2023 Dec.
Artigo em Japonês | MEDLINE | ID: mdl-38303236

RESUMO

A 58-year-old woman presented with a complaint of weight loss. Abdominal computed tomography showed dilatation of the biliary and pancreatic ducts and a mural nodule in the pancreatic duct. The diagnosis was intraductal papillary mucinous neoplasm(IPMN). Endoscopic retrograde cholangiopancreatography(ERCP)and cholangioscopy revealed a fistula between the common bile duct and the IPMN. A sudden increase in hepatobiliary enzymes was noted preoperatively. ERCP showed that the common bile duct was obstructed by mucus. A nasobiliary drainage tube was inserted into the bile duct endoscopically and kept open by daily tube washing, and the liver dysfunction improved. Total pancreatectomy, splenectomy, and regional lymph node dissection were performed. Histological examination confirmed that the primary tumor was mixed invasive intraductal papillary mucinous adenocarcinoma. The patient remains alive and well with no evidence of recurrence 18 months after resection.


Assuntos
Adenocarcinoma Mucinoso , Adenocarcinoma Papilar , Carcinoma Ductal Pancreático , Hepatopatias , Neoplasias Intraductais Pancreáticas , Neoplasias Pancreáticas , Feminino , Humanos , Pessoa de Meia-Idade , Adenocarcinoma Papilar/complicações , Adenocarcinoma Papilar/cirurgia , Adenocarcinoma Papilar/diagnóstico , Ductos Biliares/patologia , Neoplasias Pancreáticas/cirurgia , Adenocarcinoma Mucinoso/complicações , Adenocarcinoma Mucinoso/cirurgia , Adenocarcinoma Mucinoso/diagnóstico , Carcinoma Ductal Pancreático/cirurgia
12.
Gan To Kagaku Ryoho ; 50(13): 1953-1955, 2023 Dec.
Artigo em Japonês | MEDLINE | ID: mdl-38303262

RESUMO

We report a case of biliary cystadenocarcinoma in which long-term survival was achieved after 2 operations for intrahepatic recurrence. A 72-year-old man with biliary cystadenocarcinoma located mainly in segment 3 of the liver underwent left hepatectomy, extrahepatic bile duct resection, and lymph node dissection. Seven years and 9 months after the initial resection, he underwent partial liver resection(segment 5)for intrahepatic recurrence detected by computed tomography. Fifteen years and 7 months after the initial resection, he underwent repeat partial resection of the liver(segment 5)for intrahepatic recurrence. Histologically, these tumors were confirmed to be recurrence of biliary cystadenocarcinoma. He remains alive and well with no further recurrence 21 years and 6 months after the initial resection. This case and a literature review suggest that hepatic resection is a useful treatment option for intrahepatic recurrence of biliary cystadenocarcinoma.


Assuntos
Neoplasias dos Ductos Biliares , Colangiocarcinoma , Cistadenocarcinoma , Masculino , Humanos , Idoso , Ductos Biliares Intra-Hepáticos/patologia , Colangiocarcinoma/cirurgia , Fígado/patologia , Hepatectomia/métodos , Cistadenocarcinoma/cirurgia , Neoplasias dos Ductos Biliares/cirurgia , Neoplasias dos Ductos Biliares/patologia
13.
Nihon Hoshasen Gijutsu Gakkai Zasshi ; 78(12): 1436-1444, 2022 Dec 20.
Artigo em Japonês | MEDLINE | ID: mdl-36418071

RESUMO

PURPOSE: Dark band (DB) artifact in head and neck computed tomography (CT) is caused by beam hardening (BH), and decreased CT values in the X-ray target become a problem. Therefore, we investigated whether it is possible to reduce DB artifact in the head and neck with a compensation filter. METHODS: We made 2 types of filters with alcohol and water. We set each of these filters in front of the chest phantom's clavicle and evaluated DB artifact. The evaluation method measured CT values in the DB artifact area and background (BG) area by changing each compensation filter thickness and the distance between the chest phantom's surface and each compensation filter. In addition, we measured average standard deviation (SD) in the BG area by the presence of each compensation filter. RESULTS: CT values in the DB artifact area were approximate to those in the BG area by setting the thickness of each compensation filter to more than 30 mm. Furthermore, these CT values were decreased by separating the distance between the chest phantom's surface and each compensation filter. Average SD in the BG area showed no significant difference between no filter and each compensation filter. CONCLUSION: It was possible to reduce DB artifact by a compensation filter for DB.


Assuntos
Artefatos , Tomografia Computadorizada por Raios X , Tomografia Computadorizada por Raios X/métodos , Pescoço/diagnóstico por imagem , Cabeça/diagnóstico por imagem , Imagens de Fantasmas , Algoritmos
14.
Materials (Basel) ; 16(1)2022 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-36614726

RESUMO

The transverse cracking behavior of a carbon-fiber-reinforced plastic (CFRP) cross-ply laminate is investigated using a fatigue test and an entropy-based failure criterion in this study. The results of fatigue experiments show that the crack accumulation behavior depends on the cyclic number level and frequency, in which two obvious transverse cracks are observed after 104 cyclic loads and 37 transverse cracks occur after 105 cycles. The final numbers of transverse cracks decrease from 29 to 11 when the load frequency increases from 5 Hz to 10 Hz. An entropy-based failure criterion is proposed to predict the long-term lifetime of laminates under cyclic loadings. The transverse strength of 90° ply is approximated by the Weibull distribution for a realistic simulation. Progressive damage and transverse cracking behavior in CFRP ply can be reproduced due to entropy generation and strength degradation. The effects of stress level and load frequency on the transverse cracking behavior are investigated. It is discovered that, at the edge, the stress σ22 + σ33 that is a dominant factor for matrix tensile failure mode is greater than the interior at the first cycle load, and as stress levels rise, a transverse initial crack forms sooner. However, the initial transverse crack initiation is delayed as load frequencies increase. In addition, transverse crack density increases quickly after initial crack formation and then increases slowly with the number of load cycles. The proposed method's results agree well with those of the existing experimental method qualitatively. In addition, the proposed entropy-based failure criterion can account for the effect of load frequency on transverse crack growth rate, which cannot be addressed by the well-known Paris law.

15.
Int J Mol Sci ; 22(24)2021 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-34948163

RESUMO

Although numerous experiments revealed an essential role of a lipid mediator, sphingosine-1-phosphate (S1P), in breast cancer (BC) progression, the clinical significance of S1P remains unclear due to the difficulty of measuring lipids in patients. The aim of this study was to determine the plasma concentration of S1P in estrogen receptor (ER)-positive BC patients, as well as to investigate its clinical significance. We further explored the possibility of a treatment strategy targeting S1P in ER-positive BC patients by examining the effect of FTY720, a functional antagonist of S1P receptors, on hormone therapy-resistant cells. Plasma S1P levels were significantly higher in patients negative for progesterone receptor (PgR) expression than in those positive for expression (p = 0.003). Plasma S1P levels were also significantly higher in patients with larger tumor size (p = 0.012), lymph node metastasis (p = 0.014), and advanced cancer stage (p = 0.003), suggesting that higher levels of plasma S1P are associated with cancer progression. FTY720 suppressed the viability of not only wildtype MCF-7 cells, but also hormone therapy-resistant MCF-7 cells. Targeting S1P signaling in ER-positive BC appears to be a possible new treatment strategy, even for hormone therapy-resistant patients.


Assuntos
Neoplasias da Mama/metabolismo , Lisofosfolipídeos/análise , Esfingosina/análogos & derivados , Adulto , Idoso , Biomarcadores Tumorais/sangue , Neoplasias da Mama/genética , Linhagem Celular Tumoral , Progressão da Doença , Feminino , Cloridrato de Fingolimode/farmacologia , Expressão Gênica/genética , Humanos , Metástase Linfática , Lisofosfolipídeos/sangue , Lisofosfolipídeos/metabolismo , Células MCF-7 , Pessoa de Meia-Idade , Plasma/química , Receptores de Estrogênio/metabolismo , Receptores de Lisoesfingolipídeo/metabolismo , Transdução de Sinais , Esfingosina/análise , Esfingosina/sangue , Esfingosina/metabolismo , Receptores de Esfingosina-1-Fosfato/efeitos dos fármacos , Receptores de Esfingosina-1-Fosfato/metabolismo
16.
Br J Radiol ; 94(1123): 20201357, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34142867

RESUMO

OBJECTIVE: This study aimed to conduct objective and subjective comparisons of image quality among abdominal computed tomography (CT) reconstructions with deep learning reconstruction (DLR) algorithms, model-based iterative reconstruction (MBIR), and filtered back projection (FBP). METHODS: Datasets from consecutive patients who underwent low-dose liver CT were retrospectively identified. Images were reconstructed using DLR, MBIR, and FBP. Mean image noise and contrast-to-noise ratio (CNR) were calculated, and noise, artifacts, sharpness, and overall image quality were subjectively assessed. Dunnett's test was used for statistical comparisons. RESULTS: Ninety patients (67 ± 12.7 years; 63 males; mean body mass index [BMI], 25.5 kg/m2) were included. The mean noise in the abdominal aorta and hepatic parenchyma of DLR was lower than that in FBP and MBIR (p < .001). For FBP and MBIR, image noise was significantly higher for obese patients than for those with normal BMI. The CNR for the abdominal aorta and hepatic parenchyma was higher for DLR than for FBP and MBIR (p < .001). MBIR images were subjectively rated as superior to FBP images in terms of noise, artifacts, sharpness, and overall quality (p < .001). DLR images were rated as superior to MBIR images in terms of noise (p < .001) and overall quality (p = .03). CONCLUSIONS: Based on objective and subjective comparisons, the image quality of DLR was found to be superior to that of MBIR and FBP on low-dose abdominal CT. DLR was the only method for which image noise was not higher for obese patients than for those with a normal BMI. ADVANCES IN KNOWLEDGE: This study provides previously unavailable information on the properties of DLR systems and their clinical utility.


Assuntos
Aprendizado Profundo , Fígado/diagnóstico por imagem , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Radiografia Abdominal/métodos , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Artefatos , Meios de Contraste , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
18.
Endosc Int Open ; 7(9): E1187-E1191, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31475238

RESUMO

Background and study aims Although colorectal endoscopic submucosal dissection (ESD) has enabled high en bloc resection rates regardless of tumor size, colorectal ESD is still a challenging procedure. We developed a novel device called the Nelaton Attachment, which allows endoscopists to manipulate the ESD knives using two fingers of their left hand while holding the endoscope with their right hand. We retrospectively investigated the efficacy and safety of the Nelaton Attachment for colorectal ESD. We compared efficacy and safety between Nelaton Attachment and non-Nelaton Attachment groups, and also conducted an ex vivo experiment to evaluate the effect of the Nelaton Attachment. Patients and methods We retrospectively reviewed 36 consecutive patients with 37 colorectal tumors who had undergone ESD at Kishiwada Tokushukai Hospital and Naritatomisato Tokushukai Hospital between April 2016 and September 2018. The Nelaton Attachment was used for 22 of the 37 colorectal ESDs. In the ex vivo experiment, endoscopists inserted and withdrew an ESD knife 2 cm using two fingers of their left hand with and without the Nelaton Attachment. Results Median procedure time was significantly shorter in the Nelaton Attachment group (38 min [range 6 - 195 min]) compared to the non-Nelaton Attachment group (75 min [range 17 - 198 min]; P  = 0.030). Median time to complete the ex vivo experiment five times was significantly faster with the Nelaton Attachment than without the Nelaton Attachment ( P  = 0.001). Conclusions Use of the Nelaton Attachment for colorectal ESD is feasible and safe, and may facilitate colorectal ESD procedures.

19.
Mol Cancer Res ; 16(10): 1499-1511, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29858377

RESUMO

BRCA1 functions as a tumor suppressor in DNA repair and centrosome regulation. Previously, Obg-like ATPase 1 (OLA1) was shown to interact with BARD1, a heterodimer partner of BRCA1. OLA1 binds to BRCA1, BARD1, and γ-tubulin and functions in centrosome regulation. This study determined that overexpression of wild-type OLA1 (OLA1-WT) caused centrosome amplification due to centriole overduplication in mammary tissue-derived cells. Centrosome amplification induced by overexpression of the cancer-derived OLA1 mutant, which is deficient at regulating centrosome number, occurred in significantly fewer cells than in that induced by overexpression of OLA1-WT. Thus, it was hypothesized that overexpression of OLA1 with normal function efficiently induces centrosome amplification, but not that of OLA1 mutants, which are deficient at regulating centrosome number. We analyzed whether overexpression of OLA1 missense mutants of nine candidate phosphorylation residues, three residues modified with acetylation, and two ATP-binding residues caused centrosome amplification and identified five missense mutants that are deficient in the regulation of centrosome number. Three of them did not bind to BARD1. Two phosphomimetic mutations restored the binding to BARD1 and the efficient centrosome amplification by their overexpression. Knockdown and overexpression of BARD1 also caused centrosome amplification. BARD1 mutant reported in cancer failed to bind to OLA1 and rescue the BARD1 knockdown-induced centrosome amplification and reduced its centrosomal localization. Combined, these data reveal that the OLA1-BARD1 interaction is important for the regulation of centrosome number.Implications: Regulation of centrosome number by BRCA1/BARD1 together with OLA1 is important for the genome integrity to prevent tumor development. Mol Cancer Res; 16(10); 1499-511. ©2018 AACR.


Assuntos
Adenosina Trifosfatases/genética , Proteína BRCA1/genética , Centrossomo/metabolismo , Proteínas de Ligação ao GTP/genética , Neoplasias/genética , Proteínas Supressoras de Tumor/genética , Ubiquitina-Proteína Ligases/genética , Centríolos/genética , Regulação Neoplásica da Expressão Gênica/genética , Técnicas de Silenciamento de Genes , Humanos , Células MCF-7 , Glândulas Mamárias Humanas/metabolismo , Glândulas Mamárias Humanas/patologia , Mutação de Sentido Incorreto/genética , Neoplasias/patologia , Fosforilação/genética , Ligação Proteica
20.
Orthop Rev (Pavia) ; 5(3): e22, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24191182

RESUMO

Recently, a remnant-preserving anterior cruciate ligament (ACL) reconstruction technique has been developed. However, the preoperative condition of remnant ACL is occasionally difficult to evaluate by magnetic resonance imaging. The purpose of this study is to evaluate the accuracy of pre-operative visualization of remnant ACL using three-dimensional computed tomography (3D-CT). The remnant ACL in 25 patients was examined by 3DCT before ACL reconstruction surgery. Findings on 3D-CT images and arthroscopy were compared. The 3D-CT images were classified into 4 groups: Group A, remnant fibers attached to the posterior cruciate ligament (PCL); Group B, those located between the PCL and the lateral wall; Group C, those attached to the lateral wall; and Group D, no identifiable remnant fibers on the tibial side. These groups were made up of 4, 3, 9 and 9 patients, respectively. Findings on 3D-CT images were identical to those during arthroscopy in 20 of 25 cases (80%). Remnant ACL can be accurately evaluated using 3D-CT in 80% of cases of torn ACL. This novel method is a useful technique for pre-operative assessment of remnant ACL.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA