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1.
J Hosp Infect ; 147: 77-82, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38492645

RESUMEN

OBJECTIVES: There is limited data on the effects of discontinuing single-room isolation while maintaining contact precautions, such as the use of gowns and gloves. In April 2021, our hospital ceased single-room isolation for patients with vancomycin-resistant enterococci (VRE) because of single-room unavailability. This study assessed the impact of this policy by examining the incidence of hospital-acquired VRE bloodstream infections (HA-VRE BSI). METHODS: This retrospective quasi-experimental study was conducted at a tertiary-care hospital in Seoul, South Korea. Time-series analysis was used to evaluate HA-VRE BSI incidence at the hospital level and in the haematology unit before (phase 1) and after (phase 2) the policy change. RESULTS: At the hospital level, HA-VRE BSI incidence level (VRE BSI per 1000 patient-days per month) and trend did not change significantly between phase 1 and phase 2 (coefficient -0.015, 95% confidence interval (CI): -0.053 to 0.023, P=0.45 and 0.000, 95% CI: -0.002 to 0.002, P=0.84, respectively). Similarly, HA-VRE BSI incidence level and trend in the haematology unit (-0.285, 95% CI: -0.618 to 0.048, P=0.09 and -0.018, 95% CI: -0.036 to 0.000, P = 0.054, respectively) did not change significantly across the two phases. CONCLUSIONS: Discontinuing single-room isolation of VRE-colonized or infected patients was not associated with an increase in the incidence of VRE BSI at the hospital level or among high-risk patients in the haematology unit. Horizontal intervention for multi-drug-resistant organisms, including measures such as enhanced hand hygiene and environmental cleaning, may be more effective at preventing VRE transmission.


Asunto(s)
Infección Hospitalaria , Infecciones por Bacterias Grampositivas , Aislamiento de Pacientes , Centros de Atención Terciaria , Enterococos Resistentes a la Vancomicina , Humanos , Enterococos Resistentes a la Vancomicina/aislamiento & purificación , Estudios Retrospectivos , Infecciones por Bacterias Grampositivas/epidemiología , Infecciones por Bacterias Grampositivas/microbiología , Infecciones por Bacterias Grampositivas/prevención & control , Incidencia , Infección Hospitalaria/epidemiología , Infección Hospitalaria/prevención & control , Infección Hospitalaria/microbiología , República de Corea/epidemiología , Control de Infecciones/métodos , Habitaciones de Pacientes , Bacteriemia/epidemiología , Bacteriemia/microbiología , Seúl/epidemiología , Masculino
2.
Clin Radiol ; 79(1): e182-e188, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37925364

RESUMEN

AIM: To analyse the clinicoradiological characteristics of traumatic inferior vena cava (IVC) injury level on preoperative computed tomography (CT). MATERIALS AND METHODS: This retrospective study evaluated patients from a single trauma centre treated for traumatic IVC injury between January 2014 and January 2021. Data on demographics, mechanism of injury, Injury Severity Score, radiological findings on CT and angiography, IVC injury level in surgical findings, complications, and clinical outcomes were collected. RESULTS: During the 8-year study period, 36 patients presented with traumatic IVC injury: 19 underwent preoperative CT with 17 (89%) blunt and two (11%) penetrating injuries. The most common primary CT sign was contour abnormality (53%, n=10), followed by intraluminal flap and active extravasation (21%, n=4). Among the secondary signs, hepatic laceration (53%, n=10) and retroperitoneal haemorrhage (53%, n=10) were the most common. Frequencies of primary and secondary signs were higher in the infrarenal and suprarenal than in the retrohepatic vena cava injuries. Diagnostic capability of preoperative CT for IVC injury differed according to the IVC level. The detection rate was the highest for an infrarenal vena cava injury at 100% (n=4), followed by that for a suprarenal, suprahepatic, and retrohepatic vena cava injuries at 75% (n=3), 43% (n=3), and 25% (n=1), respectively. CONCLUSION: CT findings of traumatic IVC injuries may vary depending on the mechanism and anatomical site of injury. Familiarity with IVC injury imaging features may help in diagnosis and surgical treatment planning.


Asunto(s)
Traumatismos Abdominales , Lesiones del Sistema Vascular , Humanos , Vena Cava Inferior/diagnóstico por imagen , Vena Cava Inferior/lesiones , Estudios Retrospectivos , Centros Traumatológicos , Hígado/diagnóstico por imagen , Lesiones del Sistema Vascular/diagnóstico por imagen , Tomografía Computarizada por Rayos X
4.
Health Educ Res ; 38(6): 563-574, 2023 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-37639385

RESUMEN

The purpose of this study was to elicit preferences for the 'format' and 'content' of tobacco treatment among college student smokers, using an online discrete choice experiment (DCE) survey. A DCE survey, supplemented with a think-aloud method, was conducted among 54 college students who smoked combustible cigarettes and/or e-cigarettes. Conditional logistic regression models were constructed to determine optimal profiles of treatment. Cutting down nicotine rather than quitting 'cold turkey' (P < 0.001) and two-way communication (P < 0.001) were viewed as the most critical attributes for the intervention 'format'; changing behaviors rather than social groups/peers (P < 0.001) and autonomy (P < 0.001) were viewed as the most critical attributes for the intervention 'content'. Some preferences varied based on smoking subgroups. Combustible cigarette users preferred interventions with a longer time commitment (P < 0.05) and without nicotine replacement therapies (NRTs) (P < 0.001). Think-aloud data supported the DCE findings and further revealed a strong desire for cutting down nicotine and keeping social groups/peers and misconceptions regarding NRTs. Our study findings can guide tobacco treatment tailored to college students. These treatments should be tailored to specific smoker subgroups.


Asunto(s)
Sistemas Electrónicos de Liberación de Nicotina , Cese del Hábito de Fumar , Productos de Tabaco , Humanos , Nicotina , Cese del Hábito de Fumar/métodos , Dispositivos para Dejar de Fumar Tabaco , Estudiantes
6.
Public Health Pract (Oxf) ; 5: 100360, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36743452

RESUMEN

Objectives: Even with significant advances to advance the health status of the general American population, the increased prevalence of mental health conditions and re-emergence of highly infectious diseases across all levels of society present a significant threat. This study aimed to quantify the effects of pandemic-, healthcare-related, and sociodemographic variables on adverse mental health outcomes, and determine their relative magnitudes. Study design: This study employed publicly available data from the Household Pulse Survey, conducted by the United States Census Bureau to examine the social and economic impacts of the COVID-19 pandemic on American households. Methods: A multiple regression model formed the basis of analysis, with adverse mental health as the outcome and various pandemic-, healthcare-related, and sociodemographic variables as predictors. Missing data was handled using multiple imputation. Results: The factors with significant contributions to adverse mental health outcomes were those associated with mental health services and prescriptions. General healthcare-related variables followed those specific to mental health, along with sociodemographic variables contributing smaller changes. There were differential outcomes in mental health that were in part attributable to sociodemographic factors, but also a lack of access to both mental and physical healthcare due to factors both related and unrelated to the ongoing pandemic. Conclusions: There is a need for policymakers and other stakeholders to work towards a mental health system that is more robust to restrictions brought on by events like the COVID-19 pandemic, and to address inequities in health care that have been exacerbated.

7.
J Hosp Infect ; 131: 228-233, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36460176

RESUMEN

BACKGROUND: There have been limited data on the risk of onward transmission from individuals with Omicron variant infections who return to work after a 5-day isolation. AIM: To evaluate the risk of transmission from healthcare workers (HCWs) with Omicron variant who returned to work after a 5-day isolation and the viable-virus shedding kinetics. METHODS: This investigation was performed in a tertiary care hospital, Seoul, South Korea. In a secondary transmission study, we retrospectively reviewed the data of HCWs confirmed as COVID-19 from March 14th to April 3rd, 2022 in units with five or more COVID-19-infected HCWs per week. In the viral shedding kinetics study, HCWs with Omicron variant infection who agreed with daily saliva sampling were enrolled between February and March, 2022. FINDINGS: Of the 248 HCWs who were diagnosed with COVID-19 within 5 days of the return of an infected HCW, 18 (7%) had contact with the returned HCW within 1-5 days after their return. Of these, nine (4%) had an epidemiologic link other than with the returning HCW, and nine (4%) had contact with the returning HCW, without any other epidemiologic link. In the study of the kinetics of virus shedding (N = 32), the median time from symptom onset to negative conversion of viable virus was four days (95% confidence interval: 3-5). CONCLUSION: Our data suggest that the residual risk of virus transmission after 5 days of isolation following diagnosis or symptom onset is low.


Asunto(s)
COVID-19 , Humanos , SARS-CoV-2 , Estudios Retrospectivos , Cinética , Personal de Salud
8.
Clin Oncol (R Coll Radiol) ; 35(1): e10-e19, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-35918275

RESUMEN

AIMS: Objective evaluation of radiation dermatitis is important for analysing the correlation between the severity of radiation dermatitis and dose distribution in clinical practice and for reliable reporting in clinical trials. We developed a novel radiation dermatitis segmentation system based on convolutional neural networks (CNNs) to consistently evaluate radiation dermatitis. MATERIALS AND METHODS: The radiation dermatitis segmentation system is designed to segment the radiation dermatitis occurrence area using skin photographs and skin-dose distribution. A CNN architecture with a dilated convolution layer and skip connection was designed to estimate the radiation dermatitis area. Seventy-three skin photographs obtained from patients undergoing radiotherapy were collected for training and testing. The ground truth of radiation dermatitis segmentation is manually delineated from the skin photograph by an experienced radiation oncologist and medical physicist. We converted the skin photographs to RGB (red-green-blue) and CIELAB (lightness (L∗), red-green (a∗) and blue-yellow (b∗)) colour information and trained the network to segment faint and severe radiation dermatitis using three different input combinations: RGB, RGB + CIELAB (RGBLAB) and RGB + CIELAB + skin-dose distribution (RGBLAB_D). The proposed system was evaluated using the Dice similarity coefficient (DSC), sensitivity, specificity and normalised Matthews correlation coefficient (nMCC). A paired t-test was used to compare the results of different segmentation performances. RESULTS: Optimal data composition was observed in the network trained for radiation dermatitis segmentation using skin photographs and skin-dose distribution. The average DSC, sensitivity, specificity and nMCC values of RGBLAB_D were 0.62, 0.61, 0.91 and 0.77, respectively, in faint radiation dermatitis, and 0.69, 0.78, 0.96 and 0.83, respectively, in severe radiation dermatitis. CONCLUSION: Our study showed that CNN-based radiation dermatitis segmentation in skin photographs of patients undergoing radiotherapy can describe radiation dermatitis severity and pattern. Our study could aid in objectifying the radiation dermatitis grading and analysing the reliable correlation between dosimetric factors and the morphology of radiation dermatitis.


Asunto(s)
Aprendizaje Profundo , Radiodermatitis , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Redes Neurales de la Computación , Radiodermatitis/diagnóstico , Radiodermatitis/etiología , Planificación de la Radioterapia Asistida por Computador/métodos
9.
AJNR Am J Neuroradiol ; 43(11): 1559-1566, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36175084

RESUMEN

BACKGROUND AND PURPOSE: No report has been published on the use of DSC MR imaging, DCE MR imaging, and DWI parameters in combination to create a prognostic prediction model in glioblastoma patients. The aim of this study was to develop a machine learning-based model to find preoperative multiparametric MR imaging parameters associated with prognosis in patients with glioblastoma. Normalized CBV, volume transfer constant, and ADC of the nonenhancing T2 high-signal-intensity lesions were evaluated using K-means clustering. MATERIALS AND METHODS: A total of 142 patients with glioblastoma who underwent preoperative MR imaging and total resection were included in this retrospective study. From the normalized CBV, volume transfer constant, and ADC maps, the parametric data were sorted using the K-means clustering method. Patients were divided into training and test sets (ratio, 1:1), and the optimal number of clusters was determined using receiver operating characteristic analysis. Kaplan-Meier survival analysis and log-rank tests were performed to identify potential parametric predictors. A multivariate Cox proportional hazard model was conducted to adjust for clinical predictors. RESULTS: The nonenhancing T2 high-signal-intensity lesions were divided into 6 clusters. The cluster (class 4) with the relatively low normalized CBV and volume transfer constant value and the lowest ADC values was most associated with predicting glioblastoma prognosis. The optimal cutoff of the class 4 volume fraction of nonenhancing T2 high-signal-intensity lesions predicting 1-year progression-free survival was 9.70%, below which the cutoff was associated with longer progression-free survival. Two Kaplan-Meier curves based on the cutoff value showed a statistically significant difference (P = .037). When we adjusted for all clinical predictors, the cluster with the relatively low normalized CBV and volume transfer constant values and the lowest ADC value was an independent prognostic marker (hazard ratio, 3.04; P = .048). The multivariate Cox proportional hazard model showed a concordance index of 0.699 for progression-free survival. CONCLUSIONS: Our model showed that nonenhancing T2 high-signal-intensity lesions with the relatively low normalized CBV, low volume transfer constant values, and the lowest ADC values could serve as useful prognostic imaging markers for predicting survival outcomes in patients with glioblastoma.


Asunto(s)
Neoplasias Encefálicas , Glioblastoma , Humanos , Glioblastoma/diagnóstico por imagen , Glioblastoma/cirugía , Neoplasias Encefálicas/diagnóstico por imagen , Neoplasias Encefálicas/cirugía , Estudios Retrospectivos , Imagen por Resonancia Magnética/métodos , Pronóstico , Análisis por Conglomerados , Medios de Contraste
10.
J Dent Res ; 101(11): 1372-1379, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35774018

RESUMEN

With the increase of the adult orthodontic population, there is a need for an accurate and evidence-based prediction of the posttreatment face in 3 dimensions (3D). The objectives of this study are 1) to develop a 3D postorthodontic face prediction method based on a deep learning network using the patient-specific factors and orthodontic treatment conditions and 2) to validate the accuracy and clinical usability of the proposed method. Paired sets (n = 268) of pretreatment (T1) and posttreatment (T2) cone-beam computed tomography (CBCT) of adult patients were trained with a conditional generative adversarial network to generate 3D posttreatment facial data based on the patient's gender, age, and the changes of upper (ΔU1) and lower incisor position (ΔL1) as input. The accuracy was calculated with prediction error and mean absolute distances between real T2 (T2) and predicted T2 (PT2) near 6 perioral landmark regions, as well as percentage of prediction error less than 2 mm using test sets (n = 44). For qualitative evaluation, an online survey was conducted with experienced orthodontists as panels (n = 56). Overall, PT2 indicated similar 3D changes to the T2 face, with the most apparent changes simulated in the perioral regions. The mean prediction error was 1.2 ± 1.01 mm with 80.8% accuracy. More than 50% of the experienced orthodontists were unable to distinguish between real and predicted images. In this study, we proposed a valid 3D postorthodontic face prediction method by applying a deep learning algorithm trained with CBCT data sets.


Asunto(s)
Aprendizaje Profundo , Adulto , Algoritmos , Tomografía Computarizada de Haz Cónico , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Imagenología Tridimensional
13.
Climacteric ; 24(4): 408-414, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-34240673

RESUMEN

OBJECTIVES: An open-label, randomized trial was conducted to examine the effects of risedronate versus menopausal hormone therapy (MHT) in postmenopausal women with recent hip fracture. METHODS: Among 1165 eligible women, 281 were recruited and randomly assigned to receive oral risedronate (35 mg/week) or percutaneous estradiol gel (1.5 mg/day) plus oral micronized progesterone (100 mg/day) for 4 years. The primary end point was recurrent fracture and the secondary end points were mortality and bone mineral density (BMD). RESULTS: Kaplan-Meier analyses showed no significant differences in fracture recurrence and mortality between the two groups. The incidence of any new fracture per 100 person-years (PY) was 8.63 in the risedronate group and 12.86 in the MHT group (p = 0.180); that of clinical fracture was 4.75 and 6.99, respectively (p = 0.265); and that of asymptomatic vertebral fracture was 4.87 and 5.58, respectively (p = 0.764). The respective incidence of death per 100 PY was 3.58 and 4.40 (p = 0.503). BMD increased comparably at the lumbar spine in both groups. BMD at the total hip did not change in the risedronate group, but increased significantly by 2.8% in the MHT group. CONCLUSIONS: MHT might not differ from risedronate in the prevention of secondary fractures and death among postmenopausal women with recent hip fracture.


Asunto(s)
Fracturas de Cadera , Terapia de Reemplazo de Hormonas , Menopausia , Ácido Risedrónico/uso terapéutico , Fracturas de Cadera/epidemiología , Fracturas de Cadera/prevención & control , Humanos
14.
Animal ; 15(8): 100316, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34293582

RESUMEN

The complex microbiome colonizing the gastrointestinal tract (GIT) of ruminants plays an important role in the development of the immune system, nutrient absorption and metabolism. Hence, understanding GIT microbiota colonization in neonatal ruminants has positive impacts on host health and productivity. Microbes rapidly colonize the GIT after birth and gradually develop into a complex microbial community, which allows the possibility of GIT microbiome manipulation to enhance newborn health and growth and perhaps induce lasting effects in adult ruminants. This paper reviews recent advances in understanding how host-microbiome interactions affect the GIT development and health of neonatal ruminants. Following initial GIT microbiome colonization, continuous exposure to host-specific microorganisms is necessary for GIT development and immune system maturation. Furthermore, the early GIT microbial community structure is significantly affected by early life events, such as maternal microbiota exposure, dietary changes, age and the addition of prebiotics, probiotics and synbiotics, supporting the idea of microbial programming in early life. However, the time window in which interventions can optimally improve production and reduce gastrointestinal disease as well as the role of key host-specific microbiota constituents and host immune regulation requires further study.


Asunto(s)
Microbioma Gastrointestinal , Microbiota , Probióticos , Animales , Tracto Gastrointestinal , Prebióticos , Rumiantes
15.
AJNR Am J Neuroradiol ; 42(5): 853-860, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33632732

RESUMEN

BACKGROUND AND PURPOSE: O6-methylguanine-DNA methyltransferase (MGMT) promoter methylation status in primary and recurrent glioblastoma may change during treatment. The purpose of this study was to correlate MGMT promoter methylation status changes with DWI and DSC PWI features in patients with recurrent glioblastoma after standard treatment. MATERIALS AND METHODS: Between January 2008 and November 2016, forty patients with histologically confirmed recurrent glioblastoma were enrolled. Patients were divided into 3 groups according to the MGMT promoter methylation status for the initial and recurrent tumors: 2 groups whose MGMT promoter methylation status remained, group methylated (n = 13) or group unmethylated (n = 18), and 1 group whose MGMT promoter methylation status changed from methylated to unmethylated (n = 9). Normalized ADC and normalized relative CBV values were obtained from both the enhancing and nonenhancing regions, from which histogram parameters were calculated. The ANOVA and the Kruskal-Wallis test followed by post hoc tests were performed to compare histogram parameters among the 3 groups. The t test and Mann-Whitney U test were used to compare parameters between group methylated and group methylated to unmethylated. Receiver operating characteristic curve analysis was used to measure the predictive performance of the normalized relative CBV values between the 2 groups. RESULTS: Group methylated to unmethylated showed significantly higher means and 90th and 95th percentiles of the cumulative normalized relative CBV values of the nonenhancing region of the initial tumor than group methylated and group unmethylated (all P < .05). The mean normalized relative CBV value of the nonenhancing region of the initial tumor was the best predictor of methylation status change (P < .001), with a sensitivity of 77.78% and specificity of 92.31% at a cutoff value of 2.594. CONCLUSIONS: MGMT promoter methylation status might change in recurrent glioblastoma after standard treatment. The normalized relative CBV values of the nonenhancing region at the first preoperative MR imaging were higher in the MGMT promoter methylation change group from methylation to unmethylation in recurrent glioblastoma.


Asunto(s)
Neoplasias Encefálicas/diagnóstico por imagen , Neoplasias Encefálicas/genética , Metilasas de Modificación del ADN/genética , Enzimas Reparadoras del ADN/genética , Imagen de Difusión por Resonancia Magnética/métodos , Glioblastoma/diagnóstico por imagen , Glioblastoma/genética , Proteínas Supresoras de Tumor/genética , Adulto , Anciano , Correlación de Datos , Metilación de ADN , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Masculino , Persona de Mediana Edad , Imagen Molecular , Recurrencia Local de Neoplasia , Regiones Promotoras Genéticas , Estudios Retrospectivos
17.
Int Endod J ; 54(3): 399-412, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33089893

RESUMEN

AIM: To determine whether irisin, a newly discovered myokine that links exercise-induced and metabolic homeostasis, is able to promote odontogenic differentiation and angiogenesis in human dental pulp cells (HDPCs). METHODOLOGY: Cell viability in the presence of irisin was measured. Real-time PCR and Western blot analysis were performed to evaluate the expression levels of irisin, odontogenic and angiogenic markers. The involvement of mitogen-activated protein kinase (MAPK) and the protein kinase B (Akt) signalling pathway was evaluated by Western blot. To evaluate mineralization nodule formation, alkaline phosphatase (ALP) staining and alizarin red S staining were performed. Scratch wound assays were performed to evaluate the effects of irisin on cell migration. The data were analysed using one-way analysis of variance (anova) followed by Tukey post hoc test and Student's t-test. Statistical significance was considered at P < 0.05. RESULTS: Irisin significantly promoted odontogenic differentiation as evidenced by formation of mineralized nodules, induction of ALP activity and upregulation of odontogenic and angiogenic markers (P < 0.05). Scratch wound assays revealed that irisin significantly increased migration of HDPCs (P < 0.05). Phosphorylation of both MAPK and Akt was increased by irisin. MAPK and Akt inhibitors inhibited mineralization, cell migration and the increased expression of odontogenic and angiogenic markers. CONCLUSIONS: Irisin promoted odontogenic differentiation and mineralization and has the potential for angiogenesis through activation of the MAPK and Akt signalling pathways in HDPCs.


Asunto(s)
Pulpa Dental , Odontogénesis , Fosfatasa Alcalina/metabolismo , Diferenciación Celular , Movimiento Celular , Proliferación Celular , Células Cultivadas , Pulpa Dental/metabolismo , Humanos , Transducción de Señal
18.
Br J Surg ; 107(10): 1334-1343, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32452559

RESUMEN

BACKGROUND: In gallbladder cancer, stage T2 is subdivided by tumour location into lesions on the peritoneal side (T2a) or hepatic side (T2b). For tumours on the peritoneal side (T2a), it has been suggested that liver resection may be omitted without compromising the prognosis. However, data to validate this argument are lacking. This study aimed to investigate the prognostic value of tumour location in T2 gallbladder cancer, and to clarify the adequate extent of surgical resection. METHODS: Clinical data from patients who underwent surgery for gallbladder cancer were collected from 14 hospitals in Korea, Japan, Chile and the USA. Survival and risk factor analyses were conducted. RESULTS: Data from 937 patients were available for evaluation. The overall 5-year disease-free survival rate was 70·6 per cent, 74·5 per cent for those with T2a and 65·5 per cent among those with T2b tumours (P = 0·028). Regarding liver resection, extended cholecystectomy was associated with a better 5-year disease-free survival rate than simple cholecystectomy (73·0 versus 61·5 per cent; P = 0·012). The 5-year disease-free survival rate was marginally better for extended than simple cholecystectomy in both T2a (76·5 versus 66·1 per cent; P = 0·094) and T2b (68·2 versus 56·2 per cent; P = 0·084) disease. Five-year disease-free survival rates were similar for extended cholecystectomies including liver wedge resection versus segment IVb/V segmentectomy (74·1 versus 71·5 per cent; P = 0·720). In multivariable analysis, independent risk factors for recurrence were presence of symptoms (hazard ratio (HR) 1·52; P = 0·002), R1 resection (HR 1·96; P = 0·004) and N1/N2 status (N1: HR 3·40, P < 0·001; N2: HR 9·56, P < 0·001). Among recurrences, 70·8 per cent were metastatic. CONCLUSION: Tumour location was not an independent prognostic factor in T2 gallbladder cancer. Extended cholecystectomy was marginally superior to simple cholecystectomy. A radical operation should include liver resection and adequate node dissection.


ANTECEDENTES: En el cáncer de vesícula biliar, la ubicación del tumor subdivide el estadio T2 en tumores con invasión del lado peritoneal y del lado del hígado (T2a y T2b). Para los tumores que invaden el lado peritoneal (T2a) se sugiere que se puede obviar la resección hepática sin que ello comprometa el pronóstico. Sin embargo, este argumento no ha sido validado. El estudio tuvo como objetivo investigar el valor pronóstico de la localización del tumor en el cáncer de vesícula biliar T2 y establecer la extensión adecuada de la resección quirúrgica. MÉTODOS: Se recogieron los datos clínicos de pacientes que se sometieron a cirugía por cáncer de vesícula biliar en 14 hospitales de Corea, Japón, Chile y Estados Unidos. Se realizaron análisis de la supervivencia y de los factores de riesgo. RESULTADOS: Se dispuso de datos de 937 pacientes para ser evaluados. La tasa de supervivencia global libre de enfermedad a los 5 años fue del 70,6%, y las de T2a y T2b del 74,5% y 65,5% (P = 0,028). Con respecto a la resección hepática, la colecistectomía extendida presentó una tasa mejor de supervivencia libre de enfermedad a los 5 años que la colecistectomía simple (73,0% versus 61,5%, P = 0,012). La tasa de supervivencia libre de enfermedad a los 5 años fue marginalmente mejor para la colecistectomía extendida que para la colecistectomía simple tanto en T2a (76,5% versus 66,1%, P = 0,094) como en T2b (68,2% versus 56,2%, P = 0,084). Las tasas de supervivencia libre de enfermedad a los 5 años no fueron diferentes entre la resección hepática en cuña y la segmentectomía S4b+S5 (74,1% versus 71,5%, P = 0,720). En el análisis multivariable, los factores de riesgo independientes para la recidiva fueron la presencia de síntomas (cociente de riesgos instantáneos, hazard ratio, HR 1,52, P = 0,002), la resección R1 (HR 1,96, P = 0,004) y el estadio N1/N2 (N1 HR 3,40, P < 0,001; N2 HR 9,56, P < 0,001). El 70,8% de las recidivas eran metastásicas. CONCLUSIÓN: La localización del tumor no fue un factor pronóstico independiente en el cáncer de vesícula biliar T2. La colecistectomía extendida fue marginalmente superior que la colecistectomía simple. La cirugía radical debe incluir una resección hepática y una linfadenectomía adecuada.


Asunto(s)
Neoplasias de la Vesícula Biliar/mortalidad , Neoplasias de la Vesícula Biliar/cirugía , Adulto , Anciano , Anciano de 80 o más Años , Chile , Colecistectomía , Supervivencia sin Enfermedad , Femenino , Neoplasias de la Vesícula Biliar/patología , Hepatectomía , Humanos , Japón , Escisión del Ganglio Linfático , Masculino , Persona de Mediana Edad , Metástasis de la Neoplasia , Recurrencia Local de Neoplasia , Pronóstico , República de Corea , Factores de Riesgo , Estados Unidos
19.
Oper Dent ; 45(4): E196-E206, 2020 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-32243252

RESUMEN

CLINICAL RELEVANCE: Self-cure after tack cure could result in a lower polymerization shrinkage in some resin-based luting cements, which is closely related to lower degree of cure.


Asunto(s)
Cementos de Resina , Ensayo de Materiales , Polimerizacion
20.
Sci Rep ; 10(1): 1350, 2020 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-31992801

RESUMEN

Stacking fault energies (SFE) were determined in additively manufactured (AM) stainless steel (SS 316 L) and equiatomic CrCoNi medium-entropy alloys. AM specimens were fabricated via directed energy deposition and tensile loaded at room temperature. In situ neutron diffraction was performed to obtain a number of faulting-embedded diffraction peaks simultaneously from a set of (hkl) grains during deformation. The peak profiles diffracted from imperfect crystal structures were analyzed to correlate stacking fault probabilities and mean-square lattice strains to the SFE. The result shows that averaged SFEs are 32.8 mJ/m2 for the AM SS 316 L and 15.1 mJ/m2 for the AM CrCoNi alloys. Meanwhile, during deformation, the SFE varies from 46 to 21 mJ/m2 (AM SS 316 L) and 24 to 11 mJ/m2 (AM CrCoNi) from initial to stabilized stages, respectively. The transient SFEs are attributed to the deformation activity changes from dislocation slip to twinning as straining. The twinning deformation substructure and atomic stacking faults were confirmed by electron backscatter diffraction (EBSD) and transmission electron microscopy (TEM). The significant variance of the SFE suggests the critical twinning stress as 830 ± 25 MPa for the AM SS 316 L and 790 ± 40 MPa for AM CrCoNi, respectively.

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