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1.
Int J Biol Macromol ; 265(Pt 1): 130897, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38490376

RESUMO

Although iron in meat is an important trace element for human diet, its presence also induces postprandial oxidative stress and aggravates the condition of patients with iron overload. To overcome this situation, a type of new tunable Fe-absorption bioactive materials was constructed in this study. First, four phenolic acids (Caffeic acid, Gallic acid, Protocatechuic acid, Chlorogenic acid) were grafted onto chitosan. Then, the copolymers were prepared into micron-level microspheres by emulsification method, which were characterized in adsorption isotherms (Langmuir model), swelling behavior and digestion characteristics. In order to verify the practical application effect of microspheres, Protocatechuic acid grafted chitosan microspheres as the representative were used in sirloin powder to observe their effects in vitro digestion and rat experiment. In the present study, microspheres were innovatively applied in meat consumption, which significantly inhibited the oxidation of meat in the process of digestion and effectively controlled the iron absorption. These results are expected to play an important role in promoting the healthy consumption of meat around the world, improving gastrointestinal redox status through dietary assistance, and treating diseases related to iron overload.


Assuntos
Quitosana , Hidroxibenzoatos , Sobrecarga de Ferro , Humanos , Ratos , Animais , Microesferas , Oxirredução , Carne , Ferro , Digestão
2.
J Magn Reson Imaging ; 59(5): 1494-1513, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-37675919

RESUMO

Owing to the increasing prevalence of diabetic mellitus, diabetic kidney disease (DKD) is presently the leading cause of chronic kidney disease and end-stage renal disease worldwide. Early identification and disease interception is of paramount clinical importance for DKD management. However, current diagnostic, disease monitoring and prognostic tools are not satisfactory, due to their low sensitivity, low specificity, or invasiveness. Magnetic resonance imaging (MRI) is noninvasive and offers a host of contrast mechanisms that are sensitive to pathophysiological changes and risk factors associated with DKD. MRI tissue characterization involves structural and functional information including renal morphology (kidney volume (TKV) and parenchyma thickness using T1- or T2-weighted MRI), renal microstructure (diffusion weighted imaging, DWI), renal tissue oxygenation (blood oxygenation level dependent MRI, BOLD), renal hemodynamics (arterial spin labeling and phase contrast MRI), fibrosis (DWI) and abdominal or perirenal fat fraction (Dixon MRI). Recent (pre)clinical studies demonstrated the feasibility and potential value of DKD evaluation with MRI. Recognizing this opportunity, this review outlines key concepts and current trends in renal MRI technology for furthering our understanding of the mechanisms underlying DKD and for supplementing clinical decision-making in DKD. Progress in preclinical MRI of DKD is surveyed, and challenges for clinical translation of renal MRI are discussed. Future directions of DKD assessment and renal tissue characterization with (multi)parametric MRI are explored. Opportunities for discovery and clinical break-through are discussed including biological validation of the MRI findings, large-scale population studies, standardization of DKD protocols, the synergistic connection with data science to advance comprehensive texture analysis, and the development of smart and automatic data analysis and data visualization tools to further the concepts of virtual biopsy and personalized DKD precision medicine. We hope that this review will convey this vision and inspire the reader to become pioneers in noninvasive assessment and management of DKD with MRI. LEVEL OF EVIDENCE: 1 TECHNICAL EFFICACY: Stage 2.


Assuntos
Diabetes Mellitus , Nefropatias Diabéticas , Insuficiência Renal Crônica , Humanos , Nefropatias Diabéticas/diagnóstico por imagem , Rim/patologia , Imageamento por Ressonância Magnética/métodos , Testes de Função Renal/métodos , Insuficiência Renal Crônica/patologia
4.
Int J Nanomedicine ; 18: 3781-3800, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37457802

RESUMO

Purpose: In this study, we aimed to report the biological characteristics of the first successful synthesis of gentiopicroside-loaded chitosan nanoparticles and to evaluate the therapeutic effects and preliminary mechanisms of gentiopicrin-loaded chitosan on psoriasis-like cell and mouse models. Methods: Gentiopicroside-loaded chitosan nanoparticles (CHI-GEN) were prepared, and their biological characteristics were evaluated. HaCaT keratinocytes were stimulated with TNF-α to establish a psoriatic keratinocyte model. MTT assay and flow cytometry were used to measure cell viability and apoptosis, respectively. mRNA levels of K17, VEGF A, and IL-6 and IL-23A were detected using qRT-PCR. These tests were used to preliminarily assess the effects of CHI-GEN on keratinocyte proliferation and inflammation. Imiquimod was used to construct a psoriasis-like mice model. The severity of psoriasis was scored based on the psoriasis area severity index (PASI), H&E staining was used to observe the histological changes and the level of inflammation and cell proliferation of skin lesions was evaluated by measuring the mRNA levels of K17, IL-23A, and IL-17A using qRT-PCR. Results: The average particle size of CHI-GEN nanoparticles was approximately 100 nm, and the zeta potential was 2.69 ± 0.87 mV. The cumulative release was 67.2% in solutions of pH 5.5 at 24 h. GEN reduced TNF-α-induced excessive proliferation of HaCaT keratinocytes and downregulated mRNA levels of K17, VEGF A, and inflammatory cytokines IL-6 and IL-23A, which was more obvious in the CHI-GEN treatment group. Additionally, CHI-GEN significantly improved the severity of skin lesions in psoriasis-like mice and downregulated the mRNA expressions of IL-6, IL-23A, and IL-17A in mice skin lesions. Conclusion: In conclusion, we successfully prepared gentiopicrin-chitosan nanoparticles. Our results show that these nanoparticles have anti-psoriasis activity, inhibits keratinocyte proliferation and improves symptoms in psoriasis model mice and can be used to develop an effective strategy for the treatment of psoriasis.


Assuntos
Quitosana , Dermatite , Nanopartículas , Psoríase , Animais , Camundongos , Imiquimode/uso terapêutico , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo , Interleucina-17/metabolismo , Interleucina-17/farmacologia , Interleucina-17/uso terapêutico , Quitosana/farmacologia , Interleucina-6/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Queratinócitos , Psoríase/induzido quimicamente , Psoríase/tratamento farmacológico , Psoríase/patologia , Inflamação/induzido quimicamente , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Dermatite/tratamento farmacológico , Proliferação de Células , Camundongos Endogâmicos BALB C , Modelos Animais de Doenças
6.
Quant Imaging Med Surg ; 13(6): 3973-3987, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37284101

RESUMO

Background: Diabetic kidney disease (DKD) is the leading cause of end-stage renal disease (ESRD). There are unmet needs for noninvasive diagnosis and prognosis prediction of DKD in clinical practice. This study examines the diagnostic and prognostic value of magnetic resonance (MR) markers of renal compartment volume and the apparent diffusion coefficient (ADC) for mild, moderate, and severe DKD. Methods: This study was registered at the Chinese Clinical Trial Registry Center (registration number: ChiCTR-RRC-17012687). Sixty-seven DKD patients were prospectively randomly enrolled and underwent clinical examination and diffusion-weighted magnetic resonance imaging (DW-MRI). Patients with comorbidities that affected renal volumes or components were excluded. Ultimately, 52 DKD patients were included in the cross-sectional analysis. The ADC in the renal cortex (ADCcortex), ADC in the renal medulla (ADCmedulla) and difference between ADCcortex and ADCmedulla (ΔADC) were measured using a twelve-layer concentric objects (TLCO) approach. Renal compartment volumes of the parenchyma and pelvis were derived from T2-weighted MRI. Due to lost contact or ESRD diagnosed before follow-up (n=14), only 38 DKD patients remained for follow-up (median period =8.25 years) to investigate the correlations between MR markers and renal outcomes. The primary outcomes were the composite of doubling of the primary serum creatinine concentration or ESRD. Results: ADCcortex presented superior performance in discriminating DKD with normal and declined estimated glomerular filtration rate (eGFR) over ADCmedulla, ΔADC and renal compartment volumes with an AUC of 0.904 (sensitivity of 83% and specificity of 91%) and was moderately correlated with the clinical biomarkers eGFR and proteinuria (P<0.05). The Cox survival analysis demonstrated that ADCcortex rather than ΔADC is a predictor of renal outcomes with a hazard ratio of 3.4 (95% CI: 1.1-10.2, P<0.05) independent of baseline eGFR and proteinuria. Conclusions: ADCcortex is a valuable imaging marker for the diagnosis and prediction of renal function decline in DKD.

7.
Front Med (Lausanne) ; 9: 1024942, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36482916

RESUMO

Background: Visfatin is considered to be a "novel pro-inflammatory cytokine." Neuroinflammatory response is one of the important mechanisms of postoperative delirium (POD). The relationship between preoperative plasma visfatin and POD is unclear. Objective: To investigate the relationship between preoperative plasma visfatin concentrations and POD (primary outcome) in older hip fracture patients and to explore whether it affects POD through inflammatory factors. Materials and methods: This prospective cohort study enrolled 176 elderly patients who were scheduled for hip fracture surgery. Preoperative plasma was collected on the morning of surgery, and visfatin levels were measured. Interleukin (IL)-1 and IL-6 were measured using patients' plasma collected on the first day after surgery. We used the 3-min diagnostic interview for Confusion Assessment Method-defined delirium (3D-CAM) twice daily within the 2 days after surgery to assess whether POD had occurred. Restricted cubic splines and piecewise regression were used to explore the relationship between preoperative plasma visfatin concentrations and POD, and further mediation analysis was used to verify whether visfatin plays a role in POD through regulating inflammatory factors. Results: The incidence of POD was 18.2%. A J-shaped association was observed between preoperative plasma visfatin levels and POD. The risk of POD decreased within the lower visfatin concentration range up to 37.87 ng/ml, with a hazard ratio of 0.59 per 5 ng/ml [odds ratio (OR) = 0.59, 95% confidence interval (CI) = 0.37-0.95], but the risk increased above this concentration (P for non-linearity < 0.001, with a hazard ratio of 1.116 per 10 ng/ml; OR = 1.10, 95% CI = 1.02-1.23). Mediation effect analysis showed that when the plasma visfatin concentration was higher than 37.87 ng/ml, the effect of visfatin on POD was mediated by IL-6 (p < 0.01). A significant indirect association with postoperative plasma IL-6 was observed between preoperative plasma visfatin and POD (adjusted ß = 0.1%; 95% CI = 4.8∼38.9%; p < 0.01). Conclusion: Visfatin is the protective factor in POD when the preoperative plasma visfatin concentration is below 37.87 ng/ml, but when it exceeds 37.87 ng/ml, the visfatin concentration is a risk factor for POD, which is mediated by postoperative plasma IL-6. The results suggest that preoperative visfatin may have a dual effect on the POD occurrence. Clinical trial registration: [www.ClinicalTrials.gov], identifier [ChiCTR21 00052674].

8.
Tomography ; 8(6): 2902-2914, 2022 12 10.
Artigo em Inglês | MEDLINE | ID: mdl-36548535

RESUMO

Exposure to aristolochic acid (AA) is of increased concern due to carcinogenic and nephrotoxic effects, and incidence of aristolochic acid nephropathy (AAN) is increasing. This study characterizes renal alterations during the acute phase of AAN using parametric magnetic resonance imaging (MRI). An AAN and a control group of male Wistar rats received administration of aristolochic acid I (AAI) and polyethylene glycol (PEG), respectively, for six days. Both groups underwent MRI before and 2, 4 and 6 days after AAI or PEG administration. T2 relaxation times and apparent diffusion coefficients (ADCs) were determined for four renal layers. Serum creatinine levels (sCr) and blood urea nitrogen (BUN) were measured. Tubular injury scores (TIS) were evaluated based on histologic findings. Increased T2 values were detected since day 2 in the AAN group, but decreased ADCs and increased sCr levels and BUN were not detected until day 4. Significant linear correlations were observed between T2 of the cortex and the outer stripe of outer medulla and TIS. Our results demonstrate that parametric MRI facilitates early detection of renal injury induced by AAI in a rat model. T2 mapping may be a valuable tool for assessing kidney injury during the acute phase of AAN.


Assuntos
Injúria Renal Aguda , Rim , Ratos , Masculino , Animais , Ratos Wistar , Rim/diagnóstico por imagem , Rim/patologia , Injúria Renal Aguda/induzido quimicamente , Injúria Renal Aguda/diagnóstico por imagem , Injúria Renal Aguda/patologia , Imageamento por Ressonância Magnética
9.
Front Neurol ; 13: 978602, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36247783

RESUMO

Introduction: In recent years, the Pipeline embolization device (PED) has been widely used in the embolization of intracranial aneurysms, but there are some inconsistent findings on whether its efficacy and safety are superior to those of traditional coils embolization (coils alone, stent-assisted coils and balloon-assisted coils). The purpose of this meta-analysis was to evaluate the safety and efficacy of PED in intracranial aneurysm embolization by comparing with traditional coils. Methods: We systematically searched PubMed, Embase, Web of Science, and The Cochrane Library databases for randomized controlled trials and observational studies (case-control studies and cohort studies) comparing the efficacy of PED with traditional coils in intracranial aneurysm embolization published before April 1, 2022. The endpoints observed in this meta-analysis were procedure-related intracranial hemorrhage, procedure-related intracranial ischemia, other procedure-related complications (e.g., aneurysm rupture, neurological impairment, etc.), retreatment rate, complete occlusion (100%) of the aneurysm at the last follow-up, and favorable functional outcome (MRS ≤ 2). Results: A total of 10 studies with a total of 1,400 patients (PED group: 576 and Traditional coils: 824) were included in this meta-analysis. A comprehensive analysis of the included literature showed that the PED group had a higher rate of complete aneurysm occlusion [OR = 2.62, 95% Cl (1.94, 3.55), p < 0.00001] and Lower re-treatment rate [OR = 0.20, 95% Cl (0.12, 0.34 p < 0.00001)] compared with the traditional coil embolization group at the last follow-up. In terms of procedure-related intracranial hemorrhage [OR = 3.04, 95% Cl (1.08, 8.57), p = 0.04] and other procedure-related complications [OR = 2.91, 95% Cl (1.48, 5.57), p = 0.002], the incidence of PED was higher than that of the traditional coil embolization group. Moreover, in terms of favorable functional outcome [OR = 0.4, 95% Cl (0.22, 0.71), p = 0.002] of patients at the last follow-up, the PED group was lower than the traditional coil embolization group. There was no statistically significant between the two groups in terms of surgery-related intracranial ischemia complications [OR = 0.88, 95% Cl (0.47, 1.64), p = 0.68]. Conclusion: PED had higher rates of complete aneurysm occlusion and lower rates of aneurysm retreatment compared with traditional coils, but traditional coils was superior to the PED group in terms of procedure-related intracranial hemorrhage complication and other procedure-related complications (aneurysm rupture, neurological impairment), and favorable functional outcome (mRS ≤ 2). This result still needs to be further confirmed by additional large-sample, multicenter, prospective randomized controlled trials. Systematic review registration: https://www.crd.york.ac.uk/PROSPERO/, identifier: CRD42022325673.

10.
Saudi Pharm J ; 30(8): 1079-1087, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36164567

RESUMO

Background: Although heart failure with preserved ejection fraction (HFpEF) is a serious disease, only limited options are available for its treatment. Recent studies have analyzed the effects of phosphodiesterase (PDE) inhibitors, especially PDE5 and PDE3 inhibitors, in patients with HFpEF, with mixed outcomes. Methods: We searched PUBMED and EMBASE databases up to August 2021. Randomized controlled trials (RCTs) and clinical trials that tested the effects of PDE inhibitors on patients with HFpEF were included as eligible studies. Indicators of left ventricular (LV) function, pulmonary arterial pressure (PAP), right ventricular (RV) function, exercise capacity, and quality of life (QOL) were used to evaluate the efficacy of PDE inhibitors in HFpEF. Results: Six RCTs that reported in 7 studies were included to evaluate the efficiency of PDE inhibitors on HFpEF patients. In the pooled analysis, PDE inhibitors showed insignificant changes in the ratio of early diastolic mitral inflow to annular velocities, left atrial volume index, pulmonary artery systolic pressure (PASP), pulmonary vascular resistance (PVR), peak oxygen uptake, 6-minute walking test distance, as well as Kansas City Cardiomyopathy Questionnaire score. However, substantial improvement was observed in the tricuspid annular plane systolic excursion (TAPSE). Additionally, the regression analysis showed that PDE inhibitor administration time is a critical factor for the decrease in PASP. Conclusions: PDE inhibitors did not effectively improve LV function, PAP, exercise capacity, and QOL in patients with HFpEF. However, they improved RV function with significant difference, suggesting that PDE inhibitors might be a promising option for HFpEF patients with RV dysfunction.

11.
Crit Rev Food Sci Nutr ; : 1-19, 2022 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-35852177

RESUMO

Iron is an important trace element in the body, and it will seriously affect the body's normal operation if it is taken too much or too little. A large number of patients around the world are suffering from iron disorders. However, there are many problems using drugs to treat iron overload and causing prolonged and unbearable suffering for patients. Controlling iron absorption and utilization through diet is becoming the acceptable, safe and healthy method. At present, many literatures have reported that polyphenols can interact with iron ions and can be expected to chelate iron ions, depending on their types and structures. Besides, polyphenols often interact with other macromolecules in the diet, which may complicate this phenols-Fe behavior and give rise to the necessity of building phenolic based biopolymer materials. The biopolymer materials, constructed by self-assembly (non-covalent) or chemical modification (covalent), show excellent properties such as good permeability, targeting, biocompatibility, and high chelation ability. It is believed that this review can greatly facilitate the development of polyphenols-based biopolymer materials construction for regulating iron and improving the well-being of patients.

12.
Cell Transplant ; 31: 9636897211066508, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35156411

RESUMO

We exploited the anterior chamber of the eye (ACE) of immunodeficient mice as an ectopic site for both transplantation and microimaging of engineered surrogate islets from human induced pluripotent stem cells (hiPSC-SIs). These islets contained a majority of insulin-expressing cells, positive or negative for PDX1 and NKX6.1, and a minority of glucagon- or somatostatin-positive cells. Single, non-aggregated hiPSC-SIs were satisfactorily engrafted onto the iris. They underwent gradual vascularization and progressively increased their light scattering signals, reflecting the abundance of zinc-insulin crystal packaged inside mature insulin secretory granules. Intracameral hiPSC-SIs retrieved from recipients showed enhanced insulin immunofluorescence in correlation with the parallel increase in overall vascularization and light backscattering during the post-transplantation period. This approach enables longitudinal, nondestructive and intravital microimaging of cell fates, engraftment, vascularization and mature insulin secretory granules of single hiPSC-SI grafts, and may offer a feasible and reliable means to screen compounds for promoting in vivo hiPSC-SI maturation.


Assuntos
Células-Tronco Pluripotentes Induzidas , Células Secretoras de Insulina , Transplante das Ilhotas Pancreáticas , Ilhotas Pancreáticas , Animais , Humanos , Insulina , Camundongos
13.
Surg Endosc ; 36(5): 2734-2748, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35020057

RESUMO

BACKGROUND: Robotic distal gastrectomy (RDG) is a new technique that is rapidly gaining popularity and may help overcome the limitations of laparoscopic distal gastrectomy (LDG); however, its safety and therapeutic efficacy remain controversial. Therefore, this meta-analysis was performed to evaluate the safety and efficacy of RDG. METHODS: We searched PubMed, EMBASE, the Cochrane Library, and Web of Science for studies that compared RDG and LDG and were published between the time of database inception and May 2021. We assessed the bias risk of the observational studies using ROBIN-I, and a random effect model was always applied. RESULTS: The meta-analysis included 22 studies involving 5386 patients. Compared with LDG, RDG was associated with longer operating time (Mean Difference [MD] = 43.88, 95% CI = 35.17-52.60), less intraoperative blood loss (MD = - 24.84, 95% CI = - 41.26 to - 8.43), a higher number of retrieved lymph nodes (MD = 2.41, 95% CI = 0.77-4.05), shorter time to first flatus (MD = - 0.09, 95% CI = - 0.15 to - 0.03), shorter postoperative hospital stay (MD = - 0.68, 95% CI = - 1.27 to - 0.08), and lower incidence of pancreatic fistula (OR = 0.23, 95% CI = 0.07-0.79). Mean proximal and distal resection margin distances, time to start liquid and soft diets, and other complications were not significantly different between RDG and LDG groups. However, in the propensity-score-matched meta-analysis, the differences in time to first flatus and postoperative hospital stay between the two groups lost significance. CONCLUSIONS: Based on the available evidence, RDG appears feasible and safe, shows better surgical and oncological outcomes than LDG and, comparable postoperative recovery and postoperative complication outcomes.


Assuntos
Laparoscopia , Procedimentos Cirúrgicos Robóticos , Neoplasias Gástricas , Flatulência , Gastrectomia/efeitos adversos , Gastrectomia/métodos , Humanos , Laparoscopia/efeitos adversos , Laparoscopia/métodos , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/cirurgia , Procedimentos Cirúrgicos Robóticos/efeitos adversos , Procedimentos Cirúrgicos Robóticos/métodos , Neoplasias Gástricas/cirurgia , Resultado do Tratamento
14.
Medicine (Baltimore) ; 100(52): e28178, 2021 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-34967353

RESUMO

INTRODUCTION: Psoriasis is a common, recurrent, immune skin disease, which seriously affects patients' quality of life. In clinical practice, modified Runji ointment can effectively treat mild-to-moderate psoriasis with blood dryness syndrome, but there is a lack of high-quality evidence-based medical evidence. This trial aims to evaluate the efficacy and safety of nano-modified Runji ointment in the treatment of mild-to-moderate psoriasis with blood dryness syndrome. METHODS/DESIGN: This study will be a randomized double-blind placebo-controlled trial. A total of 80 patients will be recruited and randomly divided into an intervention group (nano-modified Runji ointment group) and a placebo group at a ratio of 1:1. All included patients will receive 8 weeks of nano-modified Runji ointment or placebo ointment respectively, twice a day. The primary outcome will be the change in psoriasis area and disease severity index score at week 8 compared to baseline. The secondary outcomes will be rash area score, pruritus score, Dermatology Life Quality Index score, traditional Chinese medicine symptom score and adverse events. DISCUSSION: This study may provide high-quality evidence for the efficacy of nano-modified Runji ointment in the treatment of mild to moderate psoriasis with blood dryness syndrome. The results of this study will be published in peer-reviewed journals. TRIAL REGISTRATION: ChiCTR, ChiCTR2000034292. Registered July 1, 2020, https://www.chictr.org.cn/edit.aspx?pid=55884&htm=4.


Assuntos
Pomadas/administração & dosagem , Psoríase/tratamento farmacológico , Doença Crônica , Método Duplo-Cego , Humanos , Recidiva Local de Neoplasia , Pomadas/efeitos adversos , Psoríase/complicações , Qualidade de Vida , Ensaios Clínicos Controlados Aleatórios como Assunto , Síndrome , Resultado do Tratamento
15.
Quant Imaging Med Surg ; 11(7): 3098-3119, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34249638

RESUMO

BACKGROUND: The use of rigid multi-exponential models (with a priori predefined numbers of components) is common practice for diffusion-weighted MRI (DWI) analysis of the kidney. This approach may not accurately reflect renal microstructure, as the data are forced to conform to the a priori assumptions of simplified models. This work examines the feasibility of less constrained, data-driven non-negative least squares (NNLS) continuum modelling for DWI of the kidney tubule system in simulations that include emulations of pathophysiological conditions. METHODS: Non-linear least squares (LS) fitting was used as reference for the simulations. For performance assessment, a threshold of 5% or 10% for the mean absolute percentage error (MAPE) of NNLS and LS results was used. As ground truth, a tri-exponential model using defined volume fractions and diffusion coefficients for each renal compartment (tubule system: Dtubules , ftubules ; renal tissue: Dtissue , ftissue ; renal blood: Dblood , fblood ;) was applied. The impact of: (I) signal-to-noise ratio (SNR) =40-1,000, (II) number of b-values (n=10-50), (III) diffusion weighting (b-rangesmall =0-800 up to b-rangelarge =0-2,180 s/mm2), and (IV) fixation of the diffusion coefficients Dtissue and Dblood was examined. NNLS was evaluated for baseline and pathophysiological conditions, namely increased tubular volume fraction (ITV) and renal fibrosis (10%: grade I, mild) and 30% (grade II, moderate). RESULTS: NNLS showed the same high degree of reliability as the non-linear LS. MAPE of the tubular volume fraction (ftubules ) decreased with increasing SNR. Increasing the number of b-values was beneficial for ftubules precision. Using the b-rangelarge led to a decrease in MAPE ftubules compared to b-rangesmall. The use of a medium b-value range of b=0-1,380 s/mm2 improved ftubules precision, and further bmax increases beyond this range yielded diminishing improvements. Fixing Dblood and Dtissue significantly reduced MAPE ftubules and provided near perfect distinction between baseline and ITV conditions. Without constraining the number of renal compartments in advance, NNLS was able to detect the (fourth) fibrotic compartment, to differentiate it from the other three diffusion components, and to distinguish between 10% vs. 30% fibrosis. CONCLUSIONS: This work demonstrates the feasibility of NNLS modelling for DWI of the kidney tubule system and shows its potential for examining diffusion compartments associated with renal pathophysiology including ITV fraction and different degrees of fibrosis.

16.
Proc Natl Acad Sci U S A ; 117(1): 448-453, 2020 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-31871187

RESUMO

Voltage-gated calcium 3.1 (CaV3.1) channels are absent in healthy mouse ß cells and mediate minor T-type Ca2+ currents in healthy rat and human ß cells but become evident under diabetic conditions. Whether more active CaV3.1 channels affect insulin secretion and glucose homeostasis remains enigmatic. We addressed this question by enhancing de novo expression of ß cell CaV3.1 channels and exploring the consequent impacts on dynamic insulin secretion and glucose homeostasis as well as underlying molecular mechanisms with a series of in vitro and in vivo approaches. We now demonstrate that a recombinant adenovirus encoding enhanced green fluorescent protein-CaV3.1 subunit (Ad-EGFP-CaV3.1) efficiently transduced rat and human islets as well as dispersed islet cells. The resulting CaV3.1 channels conducted typical T-type Ca2+ currents, leading to an enhanced basal cytosolic-free Ca2+ concentration ([Ca2+]i). Ad-EGFP-CaV3.1-transduced islets released significantly less insulin under both the basal and first phases following glucose stimulation and could no longer normalize hyperglycemia in recipient rats rendered diabetic by streptozotocin treatment. Furthermore, Ad-EGFP-CaV3.1 transduction reduced phosphorylated FoxO1 in the cytoplasm of INS-1E cells, elevated FoxO1 nuclear retention, and decreased syntaxin 1A, SNAP-25, and synaptotagmin III. These effects were prevented by inhibiting CaV3.1 channels or the Ca2+-dependent phosphatase calcineurin. Enhanced expression of ß cell CaV3.1 channels therefore impairs insulin release and glucose homeostasis by means of initial excessive Ca2+ influx, subsequent activation of calcineurin, consequent dephosphorylation and nuclear retention of FoxO1, and eventual FoxO1-mediated down-regulation of ß cell exocytotic proteins. The present work thus suggests an elevated expression of CaV3.1 channels plays a significant role in diabetes pathogenesis.


Assuntos
Canais de Cálcio Tipo T/metabolismo , Diabetes Mellitus Experimental/metabolismo , Secreção de Insulina/efeitos dos fármacos , Células Secretoras de Insulina/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Adolescente , Adulto , Animais , Células COS , Bloqueadores dos Canais de Cálcio/farmacologia , Bloqueadores dos Canais de Cálcio/uso terapêutico , Canais de Cálcio Tipo T/genética , Núcleo Celular/metabolismo , Chlorocebus aethiops , Citosol/metabolismo , Diabetes Mellitus Experimental/induzido quimicamente , Diabetes Mellitus Experimental/tratamento farmacológico , Exocitose/efeitos dos fármacos , Estudos de Viabilidade , Feminino , Proteínas de Fluorescência Verde/genética , Células HEK293 , Humanos , Insulina/metabolismo , Células Secretoras de Insulina/efeitos dos fármacos , Células Secretoras de Insulina/transplante , Masculino , Pessoa de Meia-Idade , Fosforilação , Cultura Primária de Células , Ratos , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Estreptozocina/toxicidade , Proteínas de Transporte Vesicular/metabolismo , Adulto Jovem
17.
Magn Reson Med ; 82(6): 2133-2145, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31373061

RESUMO

PURPOSE: To develop a machine learning approach using convolutional neural network for reducing MRI Gibbs-ringing artifact. THEORY AND METHODS: Gibbs-ringing artifact in MR images is caused by insufficient sampling of the high frequency data. Existing methods exploit smooth constraints to reduce intensity oscillations near sharp edges at the cost of blurring details. In this work, we developed a machine learning approach for removing the Gibbs-ringing artifact from MR images. The ringing artifact was extracted from the original image using a deep convolutional neural network and then subtracted from the original image to obtain the artifact-free image. Finally, its low-frequency k-space data were replaced with measured counterparts to enforce data fidelity further. We trained the convolutional neural network using 17,532 T2-weighted (T2W) normal brain images and evaluated its performance on T2W images of normal and tumor brains, diffusion-weighted brain images, and T2W knee images. RESULTS: The proposed method effectively removed the ringing artifact without noticeable smoothing in T2W and diffusion-weighted images. Quantitatively, images produced by the proposed method were closer to the fully-sampled reference images in terms of the root-mean-square error, peak signal-to-noise ratio, and structural similarity index, compared with current state-of-the-art methods. CONCLUSION: The proposed method presents a novel and effective approach for Gibbs-ringing reduction in MRI. The convolutional neural network-based approach is simple, computationally efficient, and highly applicable in routine clinical MRI.


Assuntos
Neoplasias Encefálicas/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Imagem de Difusão por Ressonância Magnética , Joelho/diagnóstico por imagem , Aprendizado de Máquina , Redes Neurais de Computação , Neuroimagem , Algoritmos , Artefatos , Conectoma , Difusão , Humanos , Processamento de Imagem Assistida por Computador/métodos , Imagens de Fantasmas , Processamento de Sinais Assistido por Computador , Razão Sinal-Ruído
18.
Ciênc. rural (Online) ; 49(6): e20180627, 2019. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1045380

RESUMO

ABSTRACT: A cow behavior monitoring system based on the Internet of Things (IoT) has been designed and implemented using tri-axial accelerometer, MSP430 microcontroller, wireless radio frequency (RF) module, and a laptop. The implemented system measured cow movement behavior and transmitted acceleration data to the laptop through the wireless RF module. Results were displayed on the laptop in a 2D graph, through which behavior patterns of cows were predicted. The measured data from the system were analyzed using the Multi-Back Propagation-Adaptive Boosting algorithm to determine the specific behavioral state of cows. The developed system can be used to increase classification performance of cow behavior by detecting acceleration data. Accuracy exceeded 90% for all the classified behavior categories, and the specificity of normal walking reached 96.98%. The sensitivity was good for all behavior patterns except standing up and lying down, with a maximum of 87.23% for standing. Overall, the IoT-based measurement system provides accurate and remote measurement of cow behavior, and the ensemble classification algorithm can effectively recognize various behavior patterns in dairy cows. Future research will improve the classification algorithm parameters and increase the number of enrolled cows. Once the functionality and reliability of the system have been confirmed on a large scale, commercialization may become possible.


RESUMO: Um sistema de monitoramento de comportamento de vacas baseado na Internet das Coisas (IoT) foi projetado e implementado através do uso de acelerômetro tri-axial, Microcontrolador MSP430, módulo de rádio, frequência sem fio (RF), e um portátil. O sistema implementado mediu o comportamento do movimento da vaca e transmitiu dados de aceleração ao portátil através do módulo RF sem fio. Os resultados foram exibidos no portátil em um gráfico 2D, através do qual os padrões de comportamento das vacas foram previstos. Os dados medidos do sistema foram analisados usando o Multi-retropropagação-Adaptativa algoritmo de Boosting para determinar o estado comportamental específico das vacas. O sistema desenvolvido pode ser usado para aumentar a classificação de desempenho de vaca comportamento através da detecção de aceleração de dados. A precisão excedeu 90% de todas as categorias de classificação de comportamento e a especificidade do andar normal atingiu 96.98%. A sensibilidade foi boa para todos os padrões de comportamento, exceto em pé e deitada, com um máximo de 87.23% para ficar de pé. No geral, o sistema baseado em IoT fornece medição precisa e remota do comportamento da vaca, e o algoritmo de conjunto de classificação pode efetivamente reconhecer vários padrões de comportamento em vacas leiteiras. Pesquisas futuras irão melhorar os parâmetros do algoritmo de classificação e aumentar a quantidade de vacas matriculadas. Uma vez que a funcionalidade e confiabilidade do sistema foram confirmadas em larga escala, a comercialização pode se tornar possível.

19.
Cell Death Dis ; 9(11): 1055, 2018 10 17.
Artigo em Inglês | MEDLINE | ID: mdl-30333561

RESUMO

While the application of early screening and HPV vaccines has reduced the incidence and mortality rates of cervical cancer, it remains the third most common carcinoma and fourth leading cause of cancer-associated death among women worldwide. The precise mechanisms underlying progression of cervical cancer are not fully understood at present. Here, we detected significant down-regulation of 15-hydroxyprostaglandin dehydrogenase (HPGD) in cervical cancer tissues. Overexpression of HPGD inhibited cervical cancer cell proliferation, migration and anchorage-independent growth to a significant extent. To clarify the mechanisms underlying HPGD down-regulation in cervical cancer, miRNA microarray, bioinformatics and luciferase reporter analyses were performed. HPGD was identified as a direct target of miR-146b-3p displaying up-regulation in cervical cancer tissues. Similar to the effects of HPGD overexpression, down-regulation of miR-146b-3p strongly suppressed proliferation, migration and anchorage-independent growth of cervical cancer cells. Furthermore, HPGD negatively regulated activities of STAT3 and AKT that promote cervical cancer cell proliferation. Notably, HPV oncogenes E6 and E7 were determined as potential contributory factors to these alterations. Our results collectively suggest that the HPGD/miR-146b-3p axis plays a significant role in cervical cancer and may serve as a potentially effective therapeutic target.


Assuntos
Regulação Neoplásica da Expressão Gênica , Hidroxiprostaglandina Desidrogenases/genética , MicroRNAs/genética , Infecções por Papillomavirus/genética , Proteínas Proto-Oncogênicas c-akt/genética , Fator de Transcrição STAT3/genética , Neoplasias do Colo do Útero/genética , Sequência de Bases , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Progressão da Doença , Feminino , Células HEK293 , Células HeLa , Interações Hospedeiro-Patógeno/genética , Papillomavirus Humano 16/genética , Papillomavirus Humano 16/patogenicidade , Papillomavirus Humano 18/genética , Papillomavirus Humano 18/patogenicidade , Humanos , Hidroxiprostaglandina Desidrogenases/metabolismo , MicroRNAs/metabolismo , Proteínas Oncogênicas Virais/genética , Proteínas Oncogênicas Virais/metabolismo , Proteínas E7 de Papillomavirus/genética , Proteínas E7 de Papillomavirus/metabolismo , Infecções por Papillomavirus/metabolismo , Infecções por Papillomavirus/patologia , Infecções por Papillomavirus/virologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais , Neoplasias do Colo do Útero/metabolismo , Neoplasias do Colo do Útero/patologia , Neoplasias do Colo do Útero/virologia
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