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1.
Heliyon ; 10(4): e25892, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38380020

RESUMO

Objective: Accurate and prompt detection of cracked teeth plays a critical role for human oral health. The aim of this paper is to evaluate the performance of a tooth crack segmentation model (namely, FDB-DeepLabv3+) on optical microscopic images. Method: The FDB-DeepLabv3+ model proposed here improves feature learning by replacing the backbone with ResNet50. Feature pyramid network (FPN) is introduced to fuse muti-level features. Densely linked atrous spatial pyramid pooling (Dense ASPP) is applied to achieve denser pixel sampling and wider receptive field. Bottleneck attention module (BAM) is embedded to enhance local feature extraction. Results: Through testing on a self-made hidden cracked tooth dataset, the proposed method outperforms four classical networks (FCN, U-Net, SegNet, DeepLabv3+) on segmentation results in terms of mean pixel accuracy (MPA) and mean intersection over union (MIoU). The network achieves an increase of 11.41% in MPA and 12.14% in MIoU compared to DeepLabv3+. Ablation experiments shows that all the modifications are beneficial. Conclusion: An improved network is designed for segmenting tooth surface cracks with good overall performance and robustness, which may hold significant potential in computer-aided diagnosis of cracked teeth.

2.
Clin Kidney J ; 17(1): sfad304, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38213491

RESUMO

Background: Intradialytic hypotension (IDH) is a common hemodialysis complication causing adverse outcomes. Despite the well-documented associations of ambient temperatures with fluid removal and pre-dialysis blood pressure (BP), the relationship between ambient temperature and IDH has not been adequately studied. Methods: We conducted a cohort study at a tertiary hospital in southern Taiwan between 1 January 2016 and 31 October 2021. The 24-h pre-hemodialysis mean ambient temperature was determined using hourly readings from the weather station closest to each patient's residence. IDH was defined using Fall40 [systolic BP (SBP) drop of ≥40 mmHg] or Nadir90/100 (SBP <100 if pre-dialysis SBP was ≥160, or SBP <90 mmHg). Multivariate logistic regression with generalizing estimating equations and mediation analysis were utilized. Results: The study examined 110 400 hemodialysis sessions from 182 patients, finding an IDH prevalence of 11.8% and 10.4% as per the Fall40 and Nadir90/100 criteria, respectively. It revealed a reverse J-shaped relationship between ambient temperature and IDH, with a turning point around 27°C. For temperatures under 27°C, a 4°C drop significantly increased the odds ratio of IDH to 1.292 [95% confidence interval (CI) 1.228 to 1.358] and 1.207 (95% CI 1.149 to 1.268) under the Fall40 and Nadir90/100 definitions, respectively. Lower ambient temperatures correlated with higher ultrafiltration, accounting for about 23% of the increased IDH risk. Stratified seasonal analysis indicated that this relationship was consistent in spring, autumn and winter. Conclusion: Lower ambient temperature is significantly associated with an increased risk of IDH below the threshold of 27°C, irrespective of the IDH definition. This study provides further insight into environmental risk factors for IDH in patients undergoing hemodialysis.

3.
World J Diabetes ; 14(4): 352-363, 2023 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-37122432

RESUMO

Insulin resistance is a condition in which the target tissues have a decreased response to insulin signaling, resulting in glucose uptake defect, and an increased blood sugar level. Pancreatic beta cells thus enhance insulin production to compensate. This situation may cause further beta cell dysfunction and failure, which can lead diabetes mellitus (DM). Insulin resistance is thus an important cause of the development of type 2 DM. Insulin resistance has also been found to have a strong relationship with cardiovascular disease and is common in chronic kidney disease (CKD) patients. The mechanisms of insulin resistance in CKD are complex and multifactorial. They include physical inactivity, inflammation and oxidative stress, metabolic acidosis, vitamin D deficiency, adipose tissue dysfunction, uremic toxins, and renin-angiotensin-aldosterone system activation. Currently, available anti-diabetic agents, such as biguanides, sulfonylureas, thiazolidinediones, alfa-glucosidase inhibitors, glucagon-like peptide-1-based agents, and sodium-glucose co-transporter-2 inhibitors, have different effects on insulin resistance. In this short review, we describe the potential mechanisms of insulin resistance in CKD patients. We also review the interaction of currently available anti-diabetic medications with insulin resistance.

5.
Clin Kidney J ; 15(1): 165-167, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35035947

RESUMO

Dialysis disequilibrium syndrome (DDS) is a rare complication of dialysis, especially with the general application of preventive strategies. Severe DDS with brain herniation is believed to be fatal. We present a patient presenting with bilateral uncal herniation after receiving two dialysis sessions with low-efficiency settings. Serial brain magnetic resonance imaging studies showed the temporal evolution of DDS-induced cerebral edema. With aggressive treatment of hypertonic saline and mannitol, the patient made a remarkable recovery. This case highlights that we should be cautious about this severe complication of dialysis even with preventive strategies, and recovery is possible with prompt recognition and treatment.

6.
Front Med (Lausanne) ; 8: 672651, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34124101

RESUMO

Background: Blood pressure (BP) variation may result in poor cardiovascular and renal outcomes. We investigated the pattern of seasonal BP change and its association with outcomes in patients with chronic kidney disease (CKD) living in southern Taiwan. Methods: We conducted a retrospective analysis of a prospective observational cohort consisting of outpatients with CKD for the period between December 2014 and December 2019. These patients were grouped according to the pattern of seasonal BP variation, namely, consistently higher average systolic BP (≥8 mmHg) in wintertime than summertime (Group A), consistently lower average systolic BP (≥8 mmHg) in wintertime than summertime (Group B), large variation of average systolic BP (≥8 mmHg) without a specific pattern related to weather (Group C), and little fluctuation of average systolic BP (<8 mmHg) throughout the years (Group D). The study endpoints were ≥40% reduction in estimated glomerular filtration rate (eGFR), end stage renal disease (initiation of dialysis or transplantation), or death. Results: We analyzed 507 eligible patients, of whom 17.2% exhibited consistent BP elevation in the wintertime. There were 56.8% of patients conducting regular home BP monitoring. Cox regression analysis showed home BP monitoring was independently associated with better outcome in 507 CKD patients (HR 0.72, 95% CI 0.56-0.94, P = 0.0162). Compared with the other three groups, patients with BP elevation in the wintertime (Group A) were older, had a higher prevalence of diabetic nephropathy and nephrotoxic agent use, a lower prevalence of statin use, higher eGFR decline rate, and a worse outcome. Patients with BP reduction in the wintertime (Group B) were associated with the best outcome. Cox regression analysis indicated that consistent BP elevation in the wintertime in 288 CKD patients with home BP monitoring was significantly associated with a worse composite outcome (i.e., ≥40% reduction in eGFR, end stage renal disease, or death) after adjustment for various confounding factors. Conclusion: Home BP monitoring is crucial, and associated with better outcome in CKD patients. Consistent home BP elevation from summertime to wintertime in patients with CKD was associated with a poorer composite outcome.

7.
Sci Rep ; 7(1): 10242, 2017 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-28860648

RESUMO

To examine the change in stress between before and after the Tohoku-oki Mw9.0 earthquake, we performed stress measurements after the earthquake in the Kamaishi mine in Iwate prefecture in northern Japan, located near the northern termination of the mainshock rupture, following previous measurements before the earthquake in the same mine. The results showed that the magnitudes of the three-dimensional principal stresses and the vertical stress drastically increased after the mainshock and, at 1 year after the earthquake, were more than double those before the earthquake. The principal stress magnitudes then decreased with time and returned to almost pre-earthquake levels at about 3 years after the earthquake. These changes can be interpreted in terms of coseismic rupture of the mainshock and the occurrence of aftershocks in the Sanriku-oki low-seismicity region (SLSR), where the Kamaishi mine is located. The drastic increase in stress suggests that the SLSR may act as a barrier to further rupture propagation.

8.
Sci Rep ; 7(1): 4503, 2017 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-28674446

RESUMO

The in-situ stress state in the Tarim Basin, Northwest China, down to 7 km depth is constrained using the anelastic strain recovery (ASR) method and wellbore failure analysis. Results are consistent between the two methods, and indicate that the maximum principal stresses (σ1) are close to vertical and the intermediate and minimum principal stresses (σ2 and σ3) are approximately horizontal. The states of stress at the studied wellbore is in the normal faulting stress regime within the Tarim Basin rather than in the compressional tectonic stress regime as in the periphery of the Tarim Basin, which explains the presence of the normal faults interpreted in 3-D seismic profiles collected from adjacent areas. Our results demonstrate that the ASR method can be used for rocks recovered from depths as deep as 7 km to recover reliable stress state information. The in-situ stress measurement results revealed in this paper will help future development of the petroleum resources and kinematics study in the Tarim Basin.

9.
Nature ; 546(7656): 137-140, 2017 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-28514440

RESUMO

Temperature and fluid pressure conditions control rock deformation and mineralization on geological faults, and hence the distribution of earthquakes. Typical intraplate continental crust has hydrostatic fluid pressure and a near-surface thermal gradient of 31 ± 15 degrees Celsius per kilometre. At temperatures above 300-450 degrees Celsius, usually found at depths greater than 10-15 kilometres, the intra-crystalline plasticity of quartz and feldspar relieves stress by aseismic creep and earthquakes are infrequent. Hydrothermal conditions control the stability of mineral phases and hence frictional-mechanical processes associated with earthquake rupture cycles, but there are few temperature and fluid pressure data from active plate-bounding faults. Here we report results from a borehole drilled into the upper part of the Alpine Fault, which is late in its cycle of stress accumulation and expected to rupture in a magnitude 8 earthquake in the coming decades. The borehole (depth 893 metres) revealed a pore fluid pressure gradient exceeding 9 ± 1 per cent above hydrostatic levels and an average geothermal gradient of 125 ± 55 degrees Celsius per kilometre within the hanging wall of the fault. These extreme hydrothermal conditions result from rapid fault movement, which transports rock and heat from depth, and topographically driven fluid movement that concentrates heat into valleys. Shear heating may occur within the fault but is not required to explain our observations. Our data and models show that highly anomalous fluid pressure and temperature gradients in the upper part of the seismogenic zone can be created by positive feedbacks between processes of fault slip, rock fracturing and alteration, and landscape development at plate-bounding faults.

10.
Zhejiang Da Xue Xue Bao Yi Xue Ban ; 45(4): 356-363, 2016 05 25.
Artigo em Chinês | MEDLINE | ID: mdl-27868408

RESUMO

Objective: To investigate the effect of a novel EZH2 inhibitor GSK126 on cell growth, apoptosis and migration of prostate cancer cells. Methods: Prostate cancer PC-3 and DU145 cells were treated with GSK126 at different doses. Cell growth was detected by sulforhodamine assay. Cell apoptosis was assayed by Annexin V-/PI kit. Transwell chamber and wound healing assays were conducted to detect cell migration. The mRNA level was detected by quantitative PCR, and protein expression was detected by Western blot analysis. Results: GSK126 showed significant effect on cell growth and apoptosis when the dose was higher than 50 µmol/L. Wound healing assay revealed that scratch space in PC-3 cells was significantly increased in a dose-dependent manner in GSK126-treated groups[(247.2±24.4),(347.2±19.2) and (410.5±18.1) µm in low, medium and high dose (5.0, 20.0, 50.0 µmol/L), respectively] as compared with the control group[(171.3±17.8) µm](all P<0.05). Transwell assay showed that migrated PC-3 cells in control group was 322.0±17.9,while those in GSK126-treated groups were 198.3±15.4 (low),82.7±6.2 (medium) and 30.2±4.1 (high), and the differences between the control group and GSK126-treated groups were significant(all P<0.05). In addition, GSK126 up-regulated E-cadherin mRNA expression and down-regulated N-cadherin and Vimentin mRNA expression, whereas had no significant effect on Snail, Fibronectin and VEGF-A mRNA expression. The protein expression of E-cadherin was elevated but VEGF-A protein did not change in GSK126-treated groups. Similar results were exhibited in DU145 cell. Conclusion: GSK126 can significantly inhibit cell migration and invasion in prostate cancer PC-3 and DU145 cells, which may be resulted from its effect on epithelial-mesenchymal transition. GSK126 may be used as a potential anti-prostate cancer dug in clinic.


Assuntos
Indóis/farmacologia , Neoplasias da Próstata/fisiopatologia , Piridonas/farmacologia , Antígenos CD , Apoptose/efeitos dos fármacos , Caderinas/análise , Caderinas/efeitos dos fármacos , Caderinas/metabolismo , Linhagem Celular Tumoral/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais/métodos , Proteína Potenciadora do Homólogo 2 de Zeste/análise , Proteína Potenciadora do Homólogo 2 de Zeste/efeitos dos fármacos , Proteína Potenciadora do Homólogo 2 de Zeste/metabolismo , Fibronectinas/análise , Fibronectinas/efeitos dos fármacos , Fibronectinas/metabolismo , Humanos , Masculino , Neoplasias da Próstata/química , Neoplasias da Próstata/genética , RNA Mensageiro , Regulação para Cima/efeitos dos fármacos , Fator A de Crescimento do Endotélio Vascular/análise , Fator A de Crescimento do Endotélio Vascular/efeitos dos fármacos , Vimentina/análise , Vimentina/efeitos dos fármacos , Vimentina/metabolismo
11.
Cancer Chemother Pharmacol ; 77(4): 757-65, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26898301

RESUMO

PURPOSE: To explore the effects and mechanisms of GSK126, a novel inhibitor of histone methyltransferase enhancer of zeste homologue 2, on cancer cell migration. METHODS: Gastric cancer cell line MGC803 and human lung adenocarcinoma cell line A549 were treated with GSK126 at three doses. Transwell and wound healing assays were conducted to detect cell migration. Human umbilical vein endothelial cells tube formation assay and chick embryo chorioallantoic membrane assay were performed to assess the effects of GSK126 on angiogenesis in vitro and in vivo, respectively. The mRNA level of VEGF-A was detected by quantitative PCR, and the protein levels of VEGF-A were detected both by western blot analysis and immunohistochemistry. Epi-fluorescent intensity was obtained by in vivo imaging. RESULTS: GSK126 inhibited cell migration in both MGC803 and A549 in a dose-dependent manner, as revealed by transwell and wound healing assays. The effects of GSK 126 were similar to those of gefitinib at the same doses. Moreover, GSK126 at doses of 20 and 50 µM inhibited angiogenesis both in vitro and in vivo. GSK126 reduced both the mRNA and protein expression of VEGF-A in a dose-dependent manner. Finally, in vivo imaging assay revealed that GSK126 at 200 mg/kg significantly inhibited cancer cell migration. CONCLUSIONS: GSK126 inhibits cell migration and angiogenesis in solid tumor cell lines through down-regulation of VEGF-A expression. Thus, it may be considered as a novel anticancer drug candidate for solid tumor.


Assuntos
Inibidores da Angiogênese/farmacologia , Indóis/farmacologia , Complexo Repressor Polycomb 2/antagonistas & inibidores , Piridonas/farmacologia , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Animais , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Embrião de Galinha , Proteína Potenciadora do Homólogo 2 de Zeste , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Metástase Neoplásica/prevenção & controle
12.
Dalton Trans ; 43(17): 6536-47, 2014 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-24622814

RESUMO

A simple and sensitive biosensor array based on phosphorescence detection that is able to detect oxygen and glucose in human serum, respectively, has been developed. We demonstrate an electrochemical method as a fast, effective, tunable, and versatile means of growing phosphorescence sensing material. This sensing material, crystalline iridium(III)-Zn(II) coordination polymers, namely Ir-Zn(e), was grown on a stainless steel mesh and then doped in a sol-gel matrix. The emission of Ir-Zn(e) was ascribed to a metal-to-ligand charge transfer transition (MLCT). The noteworthy oxygen-sensing properties of Ir-Zn(e) were also evaluated. The optimal oxygen-sensing conditions of Ir-Zn(e) with a deduced K(SV) value of 3.55 were 5 V and 30 °C for 1 hour. Moreover, the short response time (23 s) and the recovery time (21 s) toward oxygen have been measured. The reversibility experiment was carried out for eleven cycles. The resulting >70% recovery of intensity for Ir-Zn(e) on each cycle demonstrated a high degree of reproducibility during the sensing process. The detection limit could be 0.050% for gaseous oxygen. The sensing substrate was subsequently built up under glucose oxidase encapsulated in hydrogel and then immobilized on an egg membrane by the layer-by-layer method. Once the glucose solution was injected into this array, oxygen content depleted simultaneously with a concomitant increase in the phosphorescence of coordination polymers. The linear dynamic range for the determination of glucose was 0.1-6.0 mM, the correlation coefficient (R(2)) was 0.9940 (y = 0.75 [glucose] + 0.539), and the response time was less than 120 s. The minimum detectable concentration for glucose was calculated to be 0.05 mM from three times signal to noise. The photophysical properties of the sensing material and the effects of buffer concentration, pH, interference, matrix effect, temperature, and the stability of the biosensor array have also been studied in detail. The biosensor array was successfully applied to the determination of glucose in human serum.

13.
Science ; 339(6120): 687-90, 2013 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-23393262

RESUMO

The 2011 moment magnitude 9.0 Tohoku-Oki earthquake produced a maximum coseismic slip of more than 50 meters near the Japan trench, which could result in a completely reduced stress state in the region. We tested this hypothesis by determining the in situ stress state of the frontal prism from boreholes drilled by the Integrated Ocean Drilling Program approximately 1 year after the earthquake and by inferring the pre-earthquake stress state. On the basis of the horizontal stress orientations and magnitudes estimated from borehole breakouts and the increase in coseismic displacement during propagation of the rupture to the trench axis, in situ horizontal stress decreased during the earthquake. The stress change suggests an active slip of the frontal plate interface, which is consistent with coseismic fault weakening and a nearly total stress drop.

14.
Sci Rep ; 2: 270, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22355782

RESUMO

The impacts of the M9.0 Tohoku Earthquake on deep-sea environment were investigated 36 and 98 days after the event. The light transmission anomaly in the deep-sea water after 36 days became atypically greater (∼35%) and more extensive (thickness ∼1500 m) near the trench axis owing to the turbulent diffusion of fresh seafloor sediment, coordinated with potential seafloor displacement. In addition to the chemical influx associated with sediment diffusion, an influx of (13)C-enriched methane from the deep sub-seafloor reservoirs was estimated. This isotopically unusual methane influx was possibly triggered by the earthquake and its aftershocks that subsequently induced changes in the sub-seafloor hydrogeologic structures. The whole prokaryotic biomass and the development of specific phylotypes in the deep-sea microbial communities could rise and fall at 36 and 98 days, respectively, after the event. We may capture the snap shots of post-earthquake disturbance in deep-sea chemistry and microbial community responses.

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