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BACKGROUND: Biomarkers that can predict outcome will improve the efficacy of treatment for HNSCC patients. In this regard, we retrospectively evaluated the prognostic effect of PD1, PD-L1, and CD45RO in tongue and larynx squamous cell carcinomas. METHODS: FFPE tissue blocks of 63 larynx and 40 tongue squamous cell carcinoma samples were selected, cut into 3 µm sections, and immunohistochemically stained for PD1, PD-L1, and CD45RO. The slides were evaluated by an expert pathologist, and results were analysed using Chi-square, univariate, and multivariable Cox regression methods. RESULTS: TC-PD-L1 expression (P = 0.001) and its expression intensity (P = 0.002) were significantly correlated with a higher percentage of PD-1 + tumor infiltrating lymphocytes. In univariate survival analysis, TC-PD-L1 and its expression intensity had a significant impact on both DFS (HR: 0.203; P = 0.003 and HR: 0.320; P = 0.005) and OS (HR: 0.147; P = 0.002 and HR: 0.322; P = 0.005). Based on the multivariate analysis, PD1 (DFS: HR: 3.202; P = 0.011, OS: HR: 2.671; P = 0.027) and TC-PD-L1 (DFS: HR: 0.174; P = 0.006, OS: HR: 0.189; P = 0.009) were found to be independent prognostic markers. In the second part, scoring systems were defined based on the expression status of PD1 and PD-L1. Patients with higher scores were expected to have longer DFS and OS. In multivariate analysis, the PD1/TC-PD-L1 (DFS: P = 0.001, OS: P = 0.003) scoring systems showed superior prognostic effects. Interestingly, at the highest levels of this score, none of the patients experienced recurrence or cancer-caused death. CONCLUSION: Collectively, this study suggests negative prognostic behaviour for TC-PD-L1 protein and introduces the PD-1/TC-PD-L1 scoring system as a strong prognostic marker in OS and DFS prediction of tongue and larynx HNSCC patients.

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Carcinoma de Células Escamosas , Neoplasias de Cabeza y Cuello , Laringe , Neoplasias de la Lengua , Humanos , Antígeno B7-H1/metabolismo , Biomarcadores de Tumor/metabolismo , Carcinoma de Células Escamosas/patología , Laringe/química , Laringe/metabolismo , Laringe/patología , Linfocitos Infiltrantes de Tumor/metabolismo , Pronóstico , Receptor de Muerte Celular Programada 1/metabolismo , Estudios Retrospectivos , Carcinoma de Células Escamosas de Cabeza y Cuello/metabolismo , Carcinoma de Células Escamosas de Cabeza y Cuello/patología , Lengua/química , Lengua/metabolismo , Lengua/patología , Neoplasias de la Lengua/metabolismo , Neoplasias de la Lengua/patología

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OBJECTIVES: Background noise and linguistic violations have been shown to increase the listening effort. The present study aims to examine the effects of the interaction between background noise and linguistic violations on subjective listening effort and frontal theta oscillations during effortful listening. DESIGN: Thirty-two normal-hearing listeners participated in this study. The linguistic violation was operationalized as sentences versus random words (strings). Behavioral and electroencephalography data were collected while participants listened to sentences and strings in background noise at different signal to noise ratios (SNRs) (-9, -6, -3, 0 dB), maintained them in memory for about 3 sec in the presence of background noise, and then chose the correct sequence of words from a base matrix of words. RESULTS: Results showed the interaction effects of SNR and speech type on effort ratings. Although strings were inherently more effortful than sentences, decreasing SNR from 0 to -9 dB (in 3 dB steps), increased effort rating more for sentences than strings in each step, suggesting the more pronounced effect of noise on sentence processing that strings in low SNRs. Results also showed a significant interaction between SNR and speech type on frontal theta event-related synchronization during the retention interval. This interaction indicated that strings exhibited higher frontal theta event-related synchronization than sentences at SNR of 0 dB, suggesting increased verbal working memory demand for strings under challenging listening conditions. CONCLUSIONS: The study demonstrated that the interplay between linguistic violation and background noise shapes perceived effort and cognitive load during speech comprehension under challenging listening conditions. The differential impact of noise on processing sentences versus strings highlights the influential role of context and cognitive resource allocation in the processing of speech.

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Percepción del Habla , Humanos , Ruido , Lingüística , Pruebas Auditivas , Memoria a Corto Plazo

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Background. Depression disorder has been associated with altered oscillatory brain activity. The common methods to quantify oscillatory activity are Fourier and wavelet transforms. Both methods have difficulties distinguishing synchronized oscillatory activity from nonrhythmic and large-amplitude artifacts. Here we proposed a method called self-synchronization index (SSI) to quantify synchronized oscillatory activities in neural data. The method considers temporal characteristics of neural oscillations, amplitude, and cycles, to estimate the synchronization value for a specific frequency band. Method. The recorded electroencephalography (EEG) data of 45 depressed and 55 healthy individuals were used. The SSI method was applied to each EEG electrode filtered in the alpha frequency band (8-13 Hz). The multiple linear regression model was used to predict depression severity (Beck Depression Inventory-II scores) using alpha SSI values. Results. Patients with severe depression showed a lower alpha SSI than those with moderate depression and healthy controls in all brain regions. Moreover, the alpha SSI values negatively correlated with depression severity in all brain regions. The regression model showed a significant performance of depression severity prediction using alpha SSI. Conclusion. The findings support the SSI measure as a powerful tool for quantifying synchronous oscillatory activity. The data examined in this article support the idea that there is a strong link between the synchronization of alpha oscillatory neural activities and the level of depression. These findings yielded an objective and quantitative depression severity prediction.

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Trastorno Depresivo , Electroencefalografía , Humanos , Electroencefalografía/métodos , Encéfalo

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Listening effort can be defined as a measure of cognitive resources used by listeners to perform a listening task. Various methods have been proposed to measure this effort, yet their reliability remains unestablished, a crucial step before their application in research or clinical settings. This study encompassed 32 participants undertaking speech-in-noise tasks across two sessions, approximately a week apart. They listened to sentences and word lists at varying signal-to-noise ratios (SNRs) (-9, -6, -3 and 0 dB), then retaining them for roughly 3 s. We evaluated the test-retest reliability of self-reported effort ratings, theta (4-7 Hz) and alpha (8-13 Hz) oscillatory power, suggested previously as neural markers of listening effort. Additionally, we examined the reliability of correct word percentages. Both relative and absolute reliability were assessed using intraclass correlation coefficients (ICC) and Bland-Altman analysis. We also computed the standard error of measurement (SEM) and smallest detectable change (SDC). Our findings indicated heightened frontal midline theta power for word lists compared to sentences during the retention phase under high SNRs (0 dB, -3 dB), likely indicating a greater memory load for word lists. We observed SNR's impact on alpha power in the right central region during the listening phase and frontal theta power during the retention phase in sentences. Overall, the reliability analysis demonstrated satisfactory between-session variability for correct words and effort ratings. However, neural measures (frontal midline theta power and right central alpha power) displayed substantial variability, even though group-level outcomes appeared consistent across sessions.

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Esfuerzo de Escucha , Percepción del Habla , Humanos , Autoinforme , Reproducibilidad de los Resultados , Ruido

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Aims: Salivary gland tumors (SGTs) are a rare and diverse group of tumors that account for 3 to 10% of all head and neck malignancies. We aimed to conduct a comprehensive epidemiological analysis of SGTs in the south of Iran and compare the findings with previous reports from Iran and other parts of the world. Methods: Using a retrospective study, 405 patients diagnosed with SGTs were observed over an eight-year period between April 2013 and October 2021 in Shiraz, Iran. Patients' demographic and clinicopathological features were obtained from patients' records. Quantitative and descriptive data analysis was performed using SPSS software. Results: There were 302 benign (74.5%) and 103 (25.4%) malignant SGTs. Pleomorphic adenoma and Warthin's tumors were the most common benign SGTs (70.5% and 21.5%, respectively). The most common malignant SGTs were mucoepidermoid carcinoma and adenoid cystic carcinoma (26.2% and 22.3%, respectively). There was a statistically significant association between tumor origin and its malignancy status (p < 0.001). In addition, the results indicated that benign tumors were most commonly detected in the parotid gland (p < 0.05). The benign tumors were more frequently observed among the younger population (p = 0.006). Conclusion: In summary, the findings of the current study were mainly consistent with the previous reports from Iran and the rest of the world. Benign tumors were the most prevalent type of SGTs, and the parotid gland was the most common site. While the majority of cases that developed from the major salivary glands were benign, all the minor SGTs were malignant. Older patients were more likely to develop malignant tumors compared to younger ones. This study provides insights into the prevalence, age-related incidence, gender distribution, and geographic variation of salivary gland tumors. This can be instrumental to develop a guideline for screening, diagnosis, and determining an optimal treatment.

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The envelope of a speech signal is tracked by neural activity in the cerebral cortex. The cortical tracking occurs mainly in two frequency bands, theta (4-8 Hz) and delta (1-4 Hz). Tracking in the faster theta band has been mostly associated with lower-level acoustic processing, such as the parsing of syllables, whereas the slower tracking in the delta band relates to higher-level linguistic information of words and word sequences. However, much regarding the more specific association between cortical tracking and acoustic as well as linguistic processing remains to be uncovered. Here, we recorded EEG responses to both meaningful sentences and random word lists in different levels of signal-to-noise ratios (SNRs) that lead to different levels of speech comprehension as well as listening effort. We then related the neural signals to the acoustic stimuli by computing the phase-locking value (PLV) between the EEG recordings and the speech envelope. We found that the PLV in the delta band increases with increasing SNR for sentences but not for the random word lists, showing that the PLV in this frequency band reflects linguistic information. When attempting to disentangle the effects of SNR, speech comprehension, and listening effort, we observed a trend that the PLV in the delta band might reflect listening effort rather than the other two variables, although the effect was not statistically significant. In summary, our study shows that the PLV in the delta band reflects linguistic information and might be related to listening effort.

Asunto(s)

Corteza Auditiva , Percepción del Habla , Humanos , Habla/fisiología , Electroencefalografía , Percepción del Habla/fisiología , Corteza Auditiva/fisiología , Lingüística , Estimulación Acústica

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The aim of this research was to conduct a risk assessment and management of psychological, structural, social and economic determinants (PSSED) in a suicide attempt. The sample consisted of 353 individuals who had a recorded history of suicidal attempt; and 20 professional individuals by purposive sampling method within a descriptive cross-sectional design. Worksheets for RAM and AHP were used for data collection in this study. The rate of suicide attempt was 7.21 per 100,000 population in this study. Analysis showed that depression and mental disorders; personality disorders; family problems; socio-cultural and economic problems; lack of awareness; and low level of education have a high level of risk for suicide attempts. Psychiatric and psychological services; awareness and knowledge of life skills; medical services to dysfunctional families; development of community-based planning for PSSED of suicide; and employment and entrepreneurship services may lower suicide attempt risk.

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Toma de Decisiones , Intento de Suicidio , Humanos , Intento de Suicidio/psicología , Estudios Transversales , Factores de Riesgo , Medición de Riesgo , Ideación Suicida

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Abstract Objective: The prognostic importance of Tumor-Infiltrating Lymphocytes (TILs) in the tumor microenvironment of various cancers is increasingly recognized. In the present study, we aimed to investigate the prognostic value of CD3+, CD4+, CD8+, and CD45RO + TILs and their relation to histopathological features in larynx squamous cell carcinoma. Methods: Formalin-Fixed and Paraffin-Embedded (FFPE) samples from 63 primary larynx squamous cell carcinoma patients were immunostained for CD3, CD4, CD8, and CD45RO expression. Positive cells in micrographs from Invasive Margin (IM) and Tumor Center (CT) of tissue specimens counted by ImageJ software and their correlation with disease outcome were analyzed. Results: The expression level of TILs subpopulations was associated with clinicopathological markers as well as Overall Survival (OS) and Disease-Free Survival (DFS). In multivariate analysis, high frequency of CD45RO + cells in IM were confirmed as an independent prognostic marker for DFS (p = 0.007, HR = 4.968) and OS (p = 0.007, HR = 4.957). Similar findings were observed in the multivariate analysis of the combined frequency of CD45RO+cells in IM and CT. Conclusion: TILs are associated with patients clinicopathological features. Also, our findings indicate that CD45RO + TILs are a valuable marker for risk prediction in larynx SCC and could predict patients' outcomes.

RESUMEN

OBJECTIVE: The prognostic importance of Tumor-Infiltrating Lymphocytes (TILs) in the tumor microenvironment of various cancers is increasingly recognized. In the present study, we aimed to investigate the prognostic value of CD3+, CD4+, CD8+, and CD45RO + TILs and their relation to histopathological features in larynx squamous cell carcinoma. METHODS: Formalin-Fixed and Paraffin-Embedded (FFPE) samples from 63 primary larynx squamous cell carcinoma patients were immunostained for CD3, CD4, CD8, and CD45RO expression. Positive cells in micrographs from Invasive Margin (IM) and Tumor Center (CT) of tissue specimens counted by ImageJ software and their correlation with disease outcome were analyzed. RESULTS: The expression level of TILs subpopulations was associated with clinicopathological markers as well as Overall Survival (OS) and Disease-Free Survival (DFS). In multivariate analysis, high frequency of CD45RO + cells in IM were confirmed as an independent prognostic marker for DFS (p = 0.007, HR = 4.968) and OS (p = 0.007, HR = 4.957). Similar findings were observed in the multivariate analysis of the combined frequency of CD45RO+cells in IM and CT. CONCLUSION: TILs are associated with patients clinicopathological features. Also, our findings indicate that CD45RO + TILs are a valuable marker for risk prediction in larynx SCC and could predict patients' outcomes.

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Carcinoma de Células Escamosas , Neoplasias de Cabeza y Cuello , Humanos , Linfocitos Infiltrantes de Tumor/metabolismo , Linfocitos Infiltrantes de Tumor/patología , Carcinoma de Células Escamosas/patología , Carcinoma de Células Escamosas de Cabeza y Cuello/metabolismo , Carcinoma de Células Escamosas de Cabeza y Cuello/patología , Pronóstico , Neoplasias de Cabeza y Cuello/patología , Biomarcadores de Tumor/metabolismo , Microambiente Tumoral

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BACKGROUND: Depression is one of the most common mental disorders and the leading cause of functional disabilities. This study aims to specify whether functional connectivity and complexity of brain activity can predict the severity of depression (Beck Depression Inventory-II scores). METHODS: Resting-state, eyes-closed EEG data were recorded from 60 depressed patients. A phase synchronization measure was used to estimate functional connectivity between all pairs of the EEG channels in the delta (1-4 Hz), theta (4-8 Hz), alpha (8-13 Hz), and beta (13-30 Hz) frequency bands. To quantify the local value of functional connectivity, 2 graph theory metrics, degree, and clustering coefficient (CC), were measured. Moreover, Lempel-Ziv complexity (LZC) and fuzzy entropy (FuzzyEn) were used to measure the complexity of the EEG signal. RESULTS: Through correlation analysis, a significant negative relationship was found between graph metrics and depression severity in the alpha band. This association was strongly positive for the complexity measures in alpha and delta bands. Also, the linear regression model represented a substantial performance of depression severity prediction based on EEG features of the alpha band (r = 0.839; P < .0001, root mean square error score of 7.69). CONCLUSION: We found that the brain activity of patients with depression was related to depression severity. Abnormal brain activity reflects an increase in the severity of depression. The presented regression model provides a quantitative depression severity prediction, which can inform the development of EEG state and exhibit potential desirable application for the medical treatment of the depressive disorder.

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Encéfalo/fisiopatología , Depresión/fisiopatología , Electroencefalografía , Valor Predictivo de las Pruebas , Adulto , Electroencefalografía/métodos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Índice de Severidad de la Enfermedad , Procesamiento de Señales Asistido por Computador

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The most common disorders of the musculoskeletal system are low back disorders. They cause significant direct and indirect costs to different societies especially in lifting occupations. To reduce the risk of low back disorders, mechanical lifting aids have been used to decrease low back muscle forces. But there are very few direct ways to calculate muscle forces and examine the effect of personal lift-assist devices, so biomechanical models ought to be used to examine the quality of these devices for assisting back muscles in lifting tasks. The purpose of this study is to examine the effect of a designed wearable lift-assist vest (WLAV) in the reduction of erector spinae muscle forces during symmetric squat lifting tasks. Two techniques of muscle calculation were used, the electromyography-based method and the optimization-based model. The first uses electromyography data of erector spinae muscles and its linear relationship with muscle force to estimate their forces, and the second uses a developed musculoskeletal model to calculate back muscle forces using an optimization-based method. The results show that these techniques reduce the average value of erector spinae muscle forces by 45.38 (± 4.80) % and 42.03 (± 8.24) % respectively. Also, both methods indicated approximately the same behaviour in changing muscle forces during 10 to 60 degrees of trunk flexion using WLAV. The use of WLAV can help to reduce the activity of low back muscles in lifting tasks by transferring the external load effect to the assistive spring system utilized in it, so this device may help people lift for longer.

Asunto(s)

Músculos de la Espalda/diagnóstico por imagen , Análisis de Datos , Electromiografía , Modelos Biológicos , Análisis y Desempeño de Tareas , Dispositivos Electrónicos Vestibles , Adulto , Músculos de la Espalda/anatomía & histología , Humanos

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Nowadays, polymer reaction engineers seek robust and effective tools to synthesize complex macromolecules with well-defined and desirable microstructural and architectural characteristics. Over the past few decades, several promising approaches, such as controlled living (co)polymerization systems and chain-shuttling reactions have been proposed and widely applied to synthesize rather complex macromolecules with controlled monomer sequences. Despite the unique potential of the newly developed techniques, tailor-making the microstructure of macromolecules by suggesting the most appropriate polymerization recipe still remains a very challenging task. In the current work, two versatile and powerful tools capable of effectively addressing the aforementioned questions have been proposed and successfully put into practice. The two tools are established through the amalgamation of the Kinetic Monte Carlo simulation approach and machine learning techniques. The former, an intelligent modeling tool, is able to model and visualize the intricate inter-relationships of polymerization recipes/conditions (as input variables) and microstructural features of the produced macromolecules (as responses). The latter is capable of precisely predicting optimal copolymerization conditions to simultaneously satisfy all predefined microstructural features. The effectiveness of the proposed intelligent modeling and optimization techniques for solving this extremely important 'inverse' engineering problem was successfully examined by investigating the possibility of tailor-making the microstructure of Olefin Block Copolymers via chain-shuttling coordination polymerization.

RESUMEN

Experimental and mathematical modeling analyses were used for controlling melt free-radical grafting of vinylic monomers on polyolefins and, thereby, reducing the disturbance of undesired cross-linking of polyolefins. Response surface, desirability function, and artificial intelligence methodologies were blended to modeling/optimization of grafting reaction in terms of vinylic monomer content, peroxide initiator concentration, and melt-processing time. An in-house code was developed based on artificial neural network that learns and mimics processing torque and grafting of glycidyl methacrylate (GMA) typical vinylic monomer on high-density polyethylene (HDPE). Application of response surface and desirability function enabled concurrent optimization of processing torque and GMA grafting on HDPE, through which we quantified for the first time competition between parallel reactions taking place during melt processing: (i) desirable grafting of GMA on HDPE; (ii) undesirable cross-linking of HDPE. The proposed robust mathematical modeling approach can precisely learn the behavior of grafting reaction of vinylic monomers on polyolefins and be placed into practice in finding exact operating condition needed for efficient grafting of reactive monomers on polyolefins.

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Various hybrid EMG-assisted optimization (EMGAO) approaches are commonly used to estimate muscle forces and joint loads of human musculoskeletal systems. Use of EMG data and optimization enables the EMGAO models to account for inter- and intra-individual variations in muscle recruitments while satisfying equilibrium requirements. Due to implications in ergonomics/prevention and rehabilitation/treatment managements of low-back disorders, there is a need to evaluate existing approaches. The present study aimed to compare predictions of three different EMGAO and one stability-based optimization (OPT) approaches for trunk muscle forces, spinal loads, and stability. Identical measured kinematics/EMG data and anatomical model were used in all approaches when simulating several sagittally symmetric static activities. Results indicated substantial inter-model differences in predicted muscle forces (up to 123% and 90% for total muscle forces in tasks with upright and flexed postures, respectively) and spinal loads (up to 74% and 78% for compression loads in upright and flexed postures, respectively). Results of EMGAO models markedly varied depending on the manner in which correction (gain) factors were introduced. Large range of gain values (from ∼0.47 to 41) was estimated in each model. While EMGAO methods predicted an unstable spine for some tasks, OPT predicted, as intended, either a meta-stable or stable states in all simulated tasks. An unrealistic unstable state of the spine predicted by EMGAO methods for some of the simulated tasks (which are in reality stable) could be an indication of the shortcoming of these models in proper prediction of muscle forces.

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Electromiografía/métodos , Fuerza Muscular/fisiología , Músculo Esquelético/fisiología , Columna Vertebral/fisiología , Torso/fisiología , Fenómenos Biomecánicos , Humanos , Masculino , Persona de Mediana Edad , Modelos Biológicos , Postura/fisiología , Presión

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BACKGROUND: Study of genomic data obtained from patient biospecimens is frequent in research of subjects with prostate and other epithelial malignancies. Understanding of the characteristics of healthy men who participate in genomic research is limited. METHODS: Patients were identified through the Prostate Cancer Genetic Risk Evaluation of SNPs Study and the Indiana University Cancer Biomarker Study, 2 population-based biomarker and cohort studies. Between 2006 and 2010, healthy Caucasian (n = 774) and healthy African American (n = 381) men were recruited and enrolled at high-volume free community health fairs. Each participant completed a demographic questionnaire and provided a blood sample for genomic research investigations. Frequency differences between demographic features of healthy African American and Caucasian men were compared and analyzed by 2-sample t test and multivariate logistic regression after adjusting potential confounding variables with significance at the P < .05 level. Features examined included: age, body mass index (BMI), income, education, marital status, tobacco, alcohol, family history, prostate-specific antigen (PSA) level, and prior prostate cancer screening history. RESULTS: Significant differences between healthy Caucasian and African American men participating in genomic research included: marital status (married, 69% Caucasian vs 46% African American, P< < .001), mean age (years, 58 Caucasian vs 54 African American, P < .001), mean BMI (kg/m(2), 30.9 Caucasian vs 32.3 African American, P = .004), annual income (P = .038), education (P = .002), and mean PSA (ng/mL, 1.2 Caucasian vs 2.0 African American, P = .005). CONCLUSIONS: Significant demographic differences exist between healthy Caucasian and African American men choosing to participate in genomic research. These differences may be important in designing genomic research study recruitment strategies.

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Investigación Biomédica/tendencias , Negro o Afroamericano , Servicios de Salud Comunitaria/tendencias , Metagenómica , Grupos Minoritarios , Selección de Paciente , Neoplasias de la Próstata/genética , Factores de Edad , Escolaridad , Predisposición Genética a la Enfermedad/etnología , Predisposición Genética a la Enfermedad/genética , Humanos , Indiana , Masculino , Estado Civil , Persona de Mediana Edad , Polimorfismo de Nucleótido Simple/genética , Neoplasias de la Próstata/epidemiología , Neoplasias de la Próstata/etnología , Estudios Retrospectivos , Factores de Riesgo , Factores Socioeconómicos , Población Blanca

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BACKGROUND AND OBJECTIVES: To evaluate whether training on a virtual reality laparoscopic simulator improves the performance on a laparoscopic box trainer. METHODS: Twenty-six subjects were trained using a box trainer, and 17 participants were trained using a virtual simulator. Participants in the experimental group completed 1 session of 5 exercises on the box trainer, 4 sessions on the virtual simulator, and a final session on the box trainer. Participants in the control group completed 6 sessions of 5 exercises on the box trainer alone. Exercises were monitored and scored for time and accuracy. Participants completed a self-evaluation survey after each session and a user satisfaction questionnaire at the end of the training. RESULTS: No significant difference existed between the 2 groups in improvement of accuracy. Pegboard time (P=0.0110) and pattern cutting time (P=0.0229) were the only exercise parameters that improved significantly more in the control group compared with the experimental group. The experimental group developed more interest in a surgical field as a result of their experience than the control group did (70.6% vs 53.8%, respectively). CONCLUSION: The virtual simulator is a reasonable alternative to the box trainer for laparoscopic skills training.

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Competencia Clínica , Laparoscopía , Urología/educación , Adulto , Simulación por Computador , Humanos , Técnicas de Sutura , Enseñanza/métodos , Procedimientos Quirúrgicos Urológicos/educación , Interfaz Usuario-Computador

RESUMEN

PURPOSE: We evaluated the face, content, and construct validity of what is, to our knowledge, the only available virtual reality simulator based on a complete kinematic representation of the da Vinci surgical system. MATERIALS AND METHODS: A total of 5 experts (EPs) and 15 novices (NVs) completed exercises on the Mimic dV-Trainer (MdVT). All participants completed three repetitions of the following tasks: (1) Ring and Cone, (2) String Walk, and (3) Letterboard. Participants rated parameters of face and content validity on a five-point Likert-scale questionnaire. Workload imposed by the simulator was assessed using a NASA Task Load Index questionnaire (TLX). RESULTS: Face validity of the MdVT was established as all 20 participants rated the simulator between average to easy-to-use and above-average to high in all parameters of realism. Participants in both EP and NV groups rated the MdVT's overall relevance to robotic surgery as very high. All five EPs assessed the simulator to be a very good practice format and very useful for training residents, thereby affirming content validity. A preliminary assessment of construct validity suggested that the MdVT could differentiate EPs from NVs. The overall TLX workload scores were lower in the EP group for all parameters except for temporal demand. CONCLUSIONS: The MdVT demonstrated excellent face and content validity as well as reasonable workload parameters. The use of this simulator in resident training may help bridge the gap between the safe acquisition of surgical skills and effective performance during live robot-assisted surgery.

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Robótica/instrumentación , Interfaz Usuario-Computador , Anastomosis Quirúrgica , Simulación por Computador , Humanos , Robótica/educación , Programas Informáticos

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Tissue engineering of implantable cellular constructs is an emerging cellular therapy for hepatic disease. In this study, we tested the ability of poly(epsilon-caprolactone) (PCL) nanofiber scaffold to support and maintain hepatic differentiation of human cord blood-derived unrestricted somatic stem cells (USSCs) in vitro. USSCs, self-renewing pluripotent cells, were isolated from human cord blood. The electrospun PCL nanofiber porous scaffold was constructed of uniform, randomly oriented nanofibers. USSCs were seeded onto PCL nanofiber scaffolds, and were induced to differentiate into hepatogenic lineages by culturing with differentiation factors for 6 weeks. RT-PCR analysis of endoderm and hepatic-specific gene expression, immunohistochemical detection of cytokeratin 18 (CK-18), alpha-fetoprotein, albumin, glycogen storage and indocyanine green uptake confirmed the differentiation of USSCs into endoderm and hepatocyte-like cells. In the present study, we show that hepatocyte-like cells differentiated from USSCs on the PCL nanofiber scaffold can be candidate for tissue engineering and cell therapy of hepatic tissues.

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Caproatos/química , Diferenciación Celular , Hepatocitos/citología , Lactonas/química , Nanoestructuras/química , Células Madre/citología , Andamios del Tejido/química , Células Cultivadas , Diseño de Equipo , Sangre Fetal/citología , Expresión Génica , Glucógeno/metabolismo , Hepatocitos/metabolismo , Humanos , Verde de Indocianina/metabolismo , Nanoestructuras/ultraestructura , Polímeros/química , Ingeniería de Tejidos/instrumentación , Ingeniería de Tejidos/métodos

RESUMEN

BACKGROUND: There is significant interest in using nanofibers in tissue engineering from stem cells. The transdifferentiation of mesenchymal stem cells into the hepatic lineage in a nanofibrous structure has not been reported. In this study, a three dimensional nanofibrous scaffold is introduced for differentiation of human bone marrow derived mesenchymal stem cells (hBMSCs) into hepatocytes. METHODS: A scaffold composed of Poly (epsilon-caprolactone), collagen and polyethersulfone was fabricated by the electrospinning technique. After characterization of isolated hBMSCs, the performance of the cells on the scaffold was evaluated by Scanning Electron Microscopy (SEM) and MTT assay. Cytological, molecular and biochemical markers were measured to confirm differentiation potential of hBMSCs into hepatocytes. RESULTS: The isolated cells possessed the basic properties of mesenchymal stem cells (MSCs). Based on scanning electron microscope (SEM) analysis and MTT assay, it was shown that the cells adhere, penetrate and proliferate on the nanofibers. Cultured cells on the nanofibers differentiated into hepatocyte-like cells and expressed hepatocyte specific markers such as albumin, alpha-fetoprotein, cytokeratin-18, cytokeratin-19 and cytochrome P450 3A4 at mRNA levels. Appearance of a considerable number of albumin-positive cells cultivated on the scaffold (47 +/- 4%) as compared to the two-dimensional culture system (28 +/- 6%) indicates the supporting role of the scaffold. The efficiency of the cells to produce albumin, urea, transferrin, serum glutamic pyruvic transaminase and serum oxaloacetate aminotransferase in hepatocytes on the scaffold further attest to the functionality of the cells. CONCLUSION: The data presented in this study show that the engineered nanofibrous scaffold is a conductive matrix which supports and enhances MSC development into functional hepatocyte-like cells.

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Materiales Biocompatibles , Células de la Médula Ósea/fisiología , Transdiferenciación Celular , Hepatocitos/fisiología , Hígado Artificial , Células Madre Mesenquimatosas/fisiología , Nanoestructuras , Ingeniería de Tejidos , Andamios del Tejido/química , Adulto , Biomarcadores/metabolismo , Células de la Médula Ósea/metabolismo , Células de la Médula Ósea/ultraestructura , Adhesión Celular , Técnicas de Cultivo de Célula , Linaje de la Célula , Proliferación Celular , Forma de la Célula , Supervivencia Celular , Transdiferenciación Celular/genética , Células Cultivadas , Colágeno/química , Regulación de la Expresión Génica , Hepatocitos/metabolismo , Hepatocitos/ultraestructura , Humanos , Células Madre Mesenquimatosas/metabolismo , Células Madre Mesenquimatosas/ultraestructura , Poliésteres/química , Polímeros/química , Sulfonas/química , Factores de Tiempo , Adulto Joven

RESUMEN

OBJECTIVE: Accurate tumor staging in renal cancer is critical for prognostic projections, follow-up schedules, clinical trials and potential systemic therapies. We studied patients undergoing laparoscopic radical nephrectomy (LRN) to determine the extent of upstaging on histopathology evaluation and correlated the clinical and pathology staging to determine the factors responsible for upstaging. PATIENTS AND METHODS: A retrospective review of patients undergoing LRN for renal cell cancer was performed. Clinical staging was determined by CT/MRI scan and/or related preoperative work up (using AJCC TNM staging criteria). Histopathology reports were studied in to determine the p-stage. Lymph node (LN) status was evaluated with attention to number and positivity of LNs in the specimen. Pathologic features that dictated upstaging were analyzed. The factors responsible for pathologic upstaging were analyzed. Statistical analysis was performed using JMP 5.0.12 software; comparisons were done using chi square or Fisher exact test. RESULTS: One hundred twenty three patients qualified for the study; mean age was 62.14+/-13.6 years, M:F ratio was 60:63 and mean tumor size of 5.3+/-2.0 cm. Clinical versus pathologic T stage distribution was T1a=41:37, T1b=43:31, T2=25:12, T3a=11:31, T3b=3:10 and T4=0:2. A total 38/123 (31%) patients were upstaged following histopathology examination. Upstaging was due to change in tumor size in 12, renal sinus fat involvement in 8, renal or adrenal vein involvement in 14, focal perirenal fat involvement in 6, and focal renal capsule penetration in 4 patients. Fifty two patients had LNs in the specimen with 19 (16%) patients had 2 or more lymph nodes and 5 had positive LNs. Mean tumor size was 5.3+/-2 cms at clinical, and 5.0+/-2.6 cms at pathology staging (P=NS). 5 patients had LN metastasis detected with tumor size of 5.5, 5.6, 6.8, and 7.2 cms in diameter, and one patient with LN metastasis was T1a stage (3.2 cm). Renal vein/inferior venal cava/adrenal vein was involved in 14 patients, adrenal was involved in 21 patients and renal sinus was involved in 19/123 patients. CONCLUSIONS: Pathologic upstaging of malignant renal neoplasms occurred in about 31% of patients following LRN. Down staging was less common and mean tumor size does not significantly change.

Asunto(s)

Carcinoma de Células Renales/patología , Carcinoma de Células Renales/cirugía , Neoplasias Renales/patología , Neoplasias Renales/cirugía , Laparoscopía/efectos adversos , Nefrectomía/efectos adversos , Femenino , Humanos , Ganglios Linfáticos/patología , Ganglios Linfáticos/cirugía , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias