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1.
Eur Radiol ; 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38913246

RESUMO

OBJECTIVE: To investigate the prognostic value of preoperative body composition and serum tumor markers (STM) in patients undergoing surgical treatment for colorectal cancer (CRC) and to establish the prognostic score for patients with CRC. METHODS: This study enrolled 365 patients (training set 245, validation set 120) with CRC who underwent surgical resection. The predictive value of various body composition features and STM for determining CRC prognosis were compared. A novel index score based on the independent risk factors from Cox regression for CRC patients was established and evaluated for its usefulness. RESULTS: Multivariate Cox regression showed that low skeletal muscle radiodensity (SMD) (p = 0.020), low subcutaneous fat area (SFA) (p = 0.029), high carcinoembryonic antigen (CEA) (p = 0.008), and high alpha-fetoprotein (AFP) (p = 0.039) were all independent prognostic factors for poor overall survival (OS). The multifactorial analysis indicated that high intermuscular fat area (IMFA) (p = 0.033) and high CEA (p = 0.009) were independent prognostic factors for poor disease-free survival (DFS). Based on these findings, two scoring systems for OS and DFS were established in the training datasets. CRC patients who scored higher on the new scoring systems had lower OS and DFS (both p < 0.001) as shown in the Kaplan-Meier survival curves in the training and validation datasets. CONCLUSION: In predicting the prognosis of CRC patients, SFA and SMD are superior to other body composition measurements. A scoring system based on body composition and STM can have prognostic value and clinical applicability. CLINICAL RELEVANCE STATEMENT: This scoring system, combining body composition and serum tumor markers, may help predict postoperative survival of CRC patients and help clinicians make well-informed decisions regarding the treatment of patients. KEY POINTS: Colorectal cancer prognosis can be related to body composition. High intermuscular fat area and CEA were independent prognostic factors for poor disease-free survival. This scoring system, based on body composition and tumor markers, can prognosticate for colorectal cancer patients.

2.
J Cachexia Sarcopenia Muscle ; 15(2): 702-717, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38293722

RESUMO

BACKGROUND: The body composition of patients with rectal cancer potentially affects postoperative outcomes. This study explored the correlations between skeletal muscle and adipose tissue quantified by computed tomography (CT) with postoperative complications and long-term prognosis in patients with rectal cancer after surgical resection. METHODS: This retrospective cohort study included patients with rectal cancer who underwent surgical resection at the Wuhan Union Hospital between 2014 and 2018. CT images within 3 months prior to the surgery were used to quantify the indices of skeletal muscle and adipose tissue at the levels of the third lumbar vertebra (L3) and umbilicus. Optimal cut-off values for each index were defined separately for males and females. Associations between body composition and postoperative complications, overall survival (OS), and disease-free survival (DFS) were evaluated using logistic and Cox proportional hazards models. RESULTS: We included 415 patients (240 males and 175 females; mean age: 57.8 ± 10.5 years). At the L3 level, a high skeletal muscle density (SMD; hazard ratio [HR]: 0.357, 95% confidence interval [CI]: 0.191-0.665, P = 0.001; HR: 0.571, 95% CI: 0.329-0.993, P = 0.047) and a high skeletal muscle index (SMI; HR: 0.435, 95% CI 0.254-0.747, P = 0.003; HR: 0.568, 95% CI: 0.359-0.897, P = 0.015) were independent prognostic factors for better OS and DFS. At the umbilical level, a large intermuscular fat area (IMFA; HR: 1.904, 95% CI: 1.068-3.395, P = 0.029; HR: 2.064, 95% CI: 1.299-3.280, P = 0.002) was an independent predictive factor for worse OS and DFS, and a high SMI (HR: 0.261, 95% CI: 0.132-0.517, P < 0.001; HR: 0.595, 95% CI: 0.387-0.913, P = 0.018) was an independent prognostic factor for better OS and DFS. The models combining body composition and clinical indicators had good predictive abilities for OS. The receiver operating characteristic areas under the curve were 0.848 and 0.860 at the L3 and umbilical levels, respectively (both P < 0.05). CONCLUSIONS: No correlations existed between CT-quantified body composition parameters and postoperative complications. However, a high SMD and high SMI were significantly associated with longer OS and DFS at the L3 level, whereas a large IMFA and low SMI were associated with worse OS and DFS at the umbilical level. Combining CT-quantified body composition and clinical indicators could help physicians predict the prognosis of patients with rectal cancer after surgery.


Assuntos
Músculo Esquelético , Neoplasias Retais , Masculino , Feminino , Humanos , Pessoa de Meia-Idade , Idoso , Estudos Retrospectivos , Músculo Esquelético/diagnóstico por imagem , Tecido Adiposo/diagnóstico por imagem , Complicações Pós-Operatórias/etiologia , Neoplasias Retais/cirurgia
3.
Sci Rep ; 14(1): 1030, 2024 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-38200187

RESUMO

Recently, the efficacy of two low-invasive treatments, ablation, and radiotherapy, has been fully compared for the patients with the early-stage hepatocellular carcinoma (HCC). However, the comparison between radiotherapy plus ablation and ablation alone has been less frequently reported. Data from the Surveillance, Epidemiology, and End Results (SEER) database were searched for early-stage HCC patients treated with ablation plus radiotherapy or ablation alone. The outcome measures were overall survival (OS) and cancer-specific survival (CSS). The propensity score matching (PSM) was used to reduce selection bias. We included 240 and 6619 patients in the radiotherapy plus ablation group and ablation group before the PSM. After PSM, 240 pairs of patients were included. The median OS (mOS) and median CSS (mCSS) of patients receiving ablation alone were longer than that of receiving radiotherapy plus ablation (mOS: 47 vs. 34 months, P = 0.019; mCSS: 77 vs. 40 months, P = 0.018, after PSM) before and after PSM. The multivariate analysis indicated that radiotherapy plus ablation independent risk factor for OS and CSS before PSM, but the significance disappeared after PSM. The detailed subgroup analyses indicated ablation alone brought more benefit in very early-stage HCC and older patients. In addition, we found different types of radiotherapy might lead to different outcomes when combined with ablation. In conclusion, ablation alone is noninferior to radiotherapy plus ablation in patients with early-stage HCC. The additional radiation prior to ablation may bring survival benefits in the patients with higher tumor stage. However, due to the risk of selection bias in that study, the results should be interpreted cautiously.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/radioterapia , Carcinoma Hepatocelular/cirurgia , Neoplasias Hepáticas/radioterapia , Neoplasias Hepáticas/cirurgia , Pesquisa , Bases de Dados Factuais , Análise Multivariada
4.
Quant Imaging Med Surg ; 12(3): 2018-2034, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35284279

RESUMO

Background: This study aimed to explore the coordinated and independent actions of lung lobes during respiration using quantitative computed tomography (CT) in order to increase our in vivo understanding of pulmonary anatomy. Methods: Cases for whom test results showed normal pulmonary function tests (PFTs) results, and normal paired inspiratory-expiratory chest CT findings, as assessed by 2 radiologists, were retrospectively included in this study. From the chest CT results, we measured quantitative indices of lung volume (LV) and mean lung density (MLD) for the total lung (TL), left lung (LL), right lung (RL), and 5 lobes in inspiratory and expiratory phases. The differences of these measures between bilateral lungs and among the lobes were evaluated to study whether they were consistent or different during respiration. Results: A total of 70 cases were included {median age of 49.5 [interquartile range (IQR), 38.0 to 60.3] years; 32 males; 38 females}. Overall, the inspiratory and expiratory volumes of the LL were smaller than those of the RL (both P<0.001). For the ventilation workload (λ, which indicates the ratio of lobar volume to total LV), the end-expiratory volume ratio (λex ) of the LL was 0.44 (IQR, 0.43 to 0.46), while the end-inspiratory volume ratio (λin ) had risen to 0.46 (IQR, 0.45 to 0.47) (P<0.001). Comparing the 5 lobes, not all lobes shared the same LV. However, the left lower lobe (LLL) and right lower lobe (RLL) showed some similarities. The λin-LLL and λin-RLL was higher than λex-LLL and λex-RLL , respectively (both P<0.001), while the ratios of the other lobes reduced. The pairwise mean absolute difference (PMAD) on λin and λex of the bilateral lower lobes was low in inspiration (0.0288) and expiration (0.0346). The MLD of bilateral lower lobes showed consistency in inspiration or in expiration (inspiration: P>0.999; expiration: P=0.975). In addition, the PMADs between the right middle lobe (RML) and other lobes were significantly larger than the PMAD between other pairs of lobes in both inspiration and expiration. Beyond that, the expiratory MLD of RML [-789.6 (IQR, -814 to -762.05) HU] was the lowest among the 5 lobes. Conclusions: We found that the LL assumes a higher workload during ventilation than it does during respiration. The 5 normal lobes were non-synchronous during respiration and contributed differently to ventilation. The bilateral lower lobes showed similarities and had a high-ventilation function, while and the LV and MLD of the RML showed the least changes within a respiration cycle.

5.
J Vasc Surg ; 75(3): 851-860.e3, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34592378

RESUMO

OBJECTIVE: To compare the 5-year outcomes of acute versus subacute thoracic endovascular aortic repair (TEVAR) in patients with uncomplicated acute type B aortic dissection (ATBAD). METHODS: Between March 2008 and September 2018, 238 consecutive patients with uncomplicated ATBAD underwent TEVAR in the acute or subacute phase and were analyzed retrospectively. The primary end points were all-cause death and aortic-related death. The secondary end point was a composite of the outcomes of death from any cause, rupture, new dissection, retrograde type A aortic dissection, endoleak, and late reintervention. Inverse probability treatment weighting was used to balance baseline characteristics. Weight-adjusted Kaplan-Meier estimate with landmark analysis and weighted Cox model were performed to assess time-to-event outcomes. RESULTS: In the inverse probability treatment weighting-adjusted population, the 30-day mortality was 1.5% in the acute TEVAR group and 0% in the subacute TEVAR group (P = .24). The incidence of 30-day adverse events occurred in 16.8% and 6.9% patients in the acute TEVAR and subacute TEVAR groups, respectively (P = .13). At 5 years, there was no statistically significant difference in all-cause death (hazard ratio [HR], 1.50; 95% confidence interval [CI], 0.59-3.81; P = .39) and aortic-related death (HR, 1.11; 95% CI, 0.34-3.60; P = .86) between the two groups. The composite outcomes occurred in 30 patients (23.0%) in the acute TEVAR group and 18 patients (22.3%) in the subacute TEVAR group, respectively (HR, 0.67; 95% CI, 0.36-1.25; P = .20). However, a landmark analysis of the composite outcomes indicated that there was a significant interaction between treatment effect and time (Pinteraction = .01), with a significantly higher incidence of the composite outcomes in the acute TEVAR group compared with the subacute TEVAR group within 1 year (HR, 0.25; 95% CI, 0.08-0.79; P = .02), and a comparable rate between 1 and 5 years (HR, 1.25; 95% CI, 0.56-2.76; P = .59). CONCLUSIONS: At the 5-year follow-up, no significant differences exist in the all-cause death and aortic-related death between acute and subacute TEVAR. However, acute TEVAR is associated with an increased rate of severe complications within 1 year, which suggests that performing TEVAR in the subacute phase of ATBAD may be the preferable option.


Assuntos
Aneurisma Aórtico/cirurgia , Dissecção Aórtica/cirurgia , Implante de Prótese Vascular , Procedimentos Endovasculares , Tempo para o Tratamento , Adulto , Dissecção Aórtica/diagnóstico por imagem , Dissecção Aórtica/mortalidade , Aneurisma Aórtico/diagnóstico por imagem , Aneurisma Aórtico/mortalidade , Prótese Vascular , Implante de Prótese Vascular/efeitos adversos , Implante de Prótese Vascular/instrumentação , Implante de Prótese Vascular/mortalidade , Procedimentos Endovasculares/efeitos adversos , Procedimentos Endovasculares/instrumentação , Procedimentos Endovasculares/mortalidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Desenho de Prótese , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Stents , Fatores de Tempo , Resultado do Tratamento
6.
Therap Adv Gastroenterol ; 15: 17562848221142417, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36600683

RESUMO

Background: Sarcopenia is a progressive generalized loss of skeletal muscle mass commonly observed in advanced stages of cancer. Objective: To assess the relationship between sarcopenia and the prognosis of patients with hepatocellular carcinoma (HCC) treated with a programmed cell death 1 (PD-1) inhibitor. Design: This is a retrospective study. Methods: This study included patients with HCC treated with camrelizumab between 1 March 2020 and 1 December 2021. The skeletal muscle area at the L3 vertebra middle level was used to calculate the skeletal muscle index. Propensity score matching (PSM) analysis was used to balance the variables between the two groups. Results: In all, 97 patients with HCC were included in the study, with 46 and 51 patients in the sarcopenia group and the non-sarcopenia group, respectively. The baseline characteristics of albumin, Child-Pugh class, albumin-bilirubin score, neutrophil-to-lymphocyte ratio, and platelet-to-lymphocyte ratio were significantly different between the two groups. In total, 26 patients from each group (n = 52) were selected after the PSM analysis. The progression-free survival (PFS) in the non-sarcopenia group was significantly longer than that in the sarcopenia group before and after PSM analysis (6.5 versus 4.8 months, p = 0.038). In addition, the disease control rate was similar before and after PSM analysis (57.7% versus 69.2%, p = 0.388). The objective response rate in the non-sarcopenia group tended to be higher than that in the sarcopenia group (11.5% versus 30.8%, p = 0.090, after PSM), but no statistically significant difference was found. The median overall survival (OS) in the non-sarcopenia group tended to longer than it in the sarcopenia group before PSM without significant differences (16.3 versus 11.3 months, p = 0.090) and the median OS was similar between the two groups after PSM (16.3 versus 16.8 months, p = 0.735). Conclusions: HCC patients with sarcopenia tended to have higher levels of inflammation and lower levels of albumin than patients without sarcopenia. Sarcopenia is associated with a shorter PFS in HCC patients treated with PD-1 inhibitor.

7.
Water Res ; 204: 117564, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34455157

RESUMO

CO2 exchanges across the water-air interface in rivers and lakes are currently believed to be responsible for the dominant share of global aquatic CO2 emissions. The gas transfer velocity (k600) is the key factor that constrains the CO2 fluxes. It is also the most problematic to establish because of its high spatial and temporal variability. Here, we have evaluated the seasonal and spatial dynamics in k600 values and their physical and chemical controlling processes by gas tracer and floating chamber (FC) methods in three reaches of a low-gradient stream channel (Guancun surface stream, 'GSS') in a karst terrain in subtropical southwestern China in December 2016 and March, July and September 2017. The k600 values were highly variable in space and time in this small stream. Physical processes, including the velocity of the stream and its slope, were found to control the variations of k600. The k600 values recorded in the dry season (March and December) were at minimal levels due to very slow flow and gentle slope, and were also affected by complexation in the solute-enriched waters. The characteristics high pH and low turbulence of gentle streams in carbonate karst areas are conducive to such complexation, which is of great significance in the limiting CO2 degassing in such regions. We have obtained the first k600 prediction model for small streams in subtropical karst regions. In conclusion, we present a comprehensive approach for predicting the k600 values in small channels by comparison of independent SF6 gas tracer and floating chamber methods.


Assuntos
Dióxido de Carbono , Rios , Dióxido de Carbono/análise , Carbonatos , Monitoramento Ambiental , Lagos , Estações do Ano
8.
Eur J Radiol ; 132: 109137, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33022550

RESUMO

PURPOSE: To assess the feasibility and advantages of high-resolution high-contrast magnetic resonance neurography (HRHC-MRN) for visualizing the morphology and pathology of the peripheral branches of cranial nerves. MATERIALS: cMRN (3D SPACE STIR sequence) and HRHC-MRN (contrast enhanced 3D SPACE STIR sequence) were performed at 3 T MR unit on 16 volunteers and 12 patients with head and neck tumors. Quantitative measurements such as SNR, CNR and CR were calculated. Three readers evaluated the continuity of the 10 major peripheral branches of cranial nerves using a 5-score scale (scores 0-4). Interobserver variability was tested. Quantitative measurements and scores were compared between cMRN and HRHC-MRN. The imaging features of the nerve pathology were analyzed. RESULTS: The CRs of nerve to bone marrow, nerve to muscle, and nerve to gland were significantly higher with HRHC-MRN than with cMRN (P = 0.014, P = 0.02, P <0.001, respectively). The scores of all nerve trunks were significantly higher with HRHC-MRN than with cMRN (all, P < 0.001). For all nerves on HRHC-MRN, the interobserver consistency was excellent across the three readers (all κ > 0.8). The scores of the inferior alveolar nerve, hypoglossal nerve, lingual nerve, facial nerve, infraorbital nerve, masseteric nerve, glossopharyngeal/vagus nerve, supraorbital nerve, auriculotemporal nerve and buccal nerve were 3.95, 3.77, 3.63, 3.25, 3.15, 3.04, 3.04, 2.87, 2.79, 1.88, respectively. CONCLUSION: HRHC-MRN provides improved visualization of the peripheral branches of cranial nerves and is a promising nerve-selective imaging method for evaluating cranial nerve morphology and pathology.


Assuntos
Nervos Cranianos , Imageamento por Ressonância Magnética , Nervos Cranianos/diagnóstico por imagem , Humanos , Imageamento Tridimensional , Espectroscopia de Ressonância Magnética , Variações Dependentes do Observador , Nervos Periféricos
9.
Sci Rep ; 9(1): 5669, 2019 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-30952912

RESUMO

The decrease in electronic device size necessitates greater understanding of gas breakdown and electron emission at microscale to optimize performance. While traditional breakdown theory using Paschen's law (PL), driven by Townsend avalanche, fails for gap distance d [Formula: see text] 15 µm, recent studies have derived analytic equations for breakdown voltage when field emission and Townsend avalanche drive breakdown. This study derives a new analytic equation that predicts breakdown voltage VB within 4% of the exact numerical results of a previously derived theory and new experimental results at subatmospheric pressure for gap distances from 1-25 µm. At atmospheric pressure, VB transitions to PL near the product of pressure and gap distance, pd, corresponding to the Paschen minimum; at lower pressures, the transition to PL occurs to the left of the minimum. We further show that the work function plays a major role in determining which side of the Paschen minimum VB transitions to PL as pressure approaches atmospheric pressure while field enhancement and the secondary emission coefficient play smaller roles. These results indicate that appropriate combinations of these parameters cause VB to transition to PL to the left of the Paschen minimum, which would yield an extended plateau similar to some microscale gas breakdown experimental observations.

10.
Artigo em Chinês | MEDLINE | ID: mdl-26999846

RESUMO

OBJECTIVE: To discuss the soft palate, hard palate and mandibule for the pathogenesis and clinical treatment of patients who have obstructive sleep apnea hypopnea syndrome. METHOD: There were 52 patients with OSAHS diagnosed by the PSG and 32 cases of normal healthy volunteers in our hospital. All objects were given 128 slice spiral CT scan of the upper airway. We measured the related indexes of the soft palate, hard palate and mandible, then analysed statistical differences between them and did Pearson correlation analysis with apnea hypoventilation index (AHI), average blood oxygen saturation (MSaO2) in PSG. RESULT: Compared with the control group, the soft palate length [(37.93 ± 5.20)mm VS (33.52 ± 4.25)mm] and the distance between mandible with cervical vertebra [(75.00 ± 7.10)mm VS (69.93 ± 5.58)mm] increased significantly, but the distance of trailing edge of hard palate to inferior margin of slope significantly reduced [(42.57 ± 4.52)mm VS (45.80 ± 2.94)mm, P < 0.01] in patients with OSAHS. Each measurement associated with AHI and MSaO2 had no significant correlation (P > 0.05). CONCLUSION: The soft palate, hard palate and mandibular are some of the important risk factors of OSAHS, and they also have reference value for the choice of clinical treatment operation. Preoperative CT examination can offer help in the treatment of OSAHS.


Assuntos
Mandíbula/anatomia & histologia , Palato Duro/anatomia & histologia , Palato Mole/anatomia & histologia , Apneia Obstrutiva do Sono/diagnóstico , Tomografia Computadorizada Espiral , Estudos de Casos e Controles , Humanos , Oximetria
11.
Pac Symp Biocomput ; : 501-12, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18229711

RESUMO

Telomerase is a ribonucleoprotein enzyme that adds telomeric DNA repeat sequences to the ends of linear chromosomes. The enzyme plays pivotal roles in cellular senescence and aging, and because it provides a telomere maintenance mechanism for approximately 90% of human cancers, it is a promising target for cancer therapy. Despite its importance, a high-resolution structure of the telomerase enzyme has been elusive, although a crystal structure of an N-terminal domain (TEN) of the telomerase reverse transcriptase subunit (TERT) from Tetrahymena has been reported. In this study, we used a comparative strategy, in which sequence-based machine learning approaches were integrated with computational structural modeling, to explore the potential conservation of structural and functional features of TERT in phylogenetically diverse species. We generated structural models of the N-terminal domains from human and yeast TERT using a combination of threading and homology modeling with the Tetrahymena TEN structure as a template. Comparative analysis of predicted and experimentally verified DNA and RNA binding residues, in the context of these structures, revealed significant similarities in nucleic acid binding surfaces of Tetrahymena and human TEN domains. In addition, the combined evidence from machine learning and structural modeling identified several specific amino acids that are likely to play a role in binding DNA or RNA, but for which no experimental evidence is currently available.


Assuntos
Telomerase/química , Sequência de Aminoácidos , Animais , Inteligência Artificial , Sítios de Ligação/genética , Biologia Computacional , Simulação por Computador , Sequência Conservada , DNA/química , DNA/metabolismo , Bases de Dados de Proteínas , Humanos , Substâncias Macromoleculares , Modelos Moleculares , Dados de Sequência Molecular , Conformação Proteica , Estrutura Terciária de Proteína , RNA/química , RNA/metabolismo , Saccharomyces cerevisiae/enzimologia , Saccharomyces cerevisiae/genética , Homologia de Sequência de Aminoácidos , Telomerase/genética , Telomerase/metabolismo , Tetrahymena/enzimologia , Tetrahymena/genética
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