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2.
Clin Kidney J ; 17(5): sfae098, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38737345

RESUMO

Background: Chronic kidney disease (CKD) is a major global health problem and its early identification would allow timely intervention to reduce complications. We performed a systematic review and meta-analysis of multivariable prediction models derived and/or validated in community-based electronic health records (EHRs) for the prediction of incident CKD in the community. Methods: Ovid Medline and Ovid Embase were searched for records from 1947 to 31 January 2024. Measures of discrimination were extracted and pooled by Bayesian meta-analysis, with heterogeneity assessed through a 95% prediction interval (PI). Risk of bias was assessed using Prediction model Risk Of Bias ASsessment Tool (PROBAST) and certainty in effect estimates by Grading of Recommendations, Assessment, Development and Evaluation (GRADE). Results: Seven studies met inclusion criteria, describing 12 prediction models, with two eligible for meta-analysis including 2 173 202 patients. The Chronic Kidney Disease Prognosis Consortium (CKD-PC) (summary c-statistic 0.847; 95% CI 0.827-0.867; 95% PI 0.780-0.905) and SCreening for Occult REnal Disease (SCORED) (summary c-statistic 0.811; 95% CI 0.691-0.926; 95% PI 0.514-0.992) models had good model discrimination performance. Risk of bias was high in 64% of models, and driven by the analysis domain. No model met eligibility for meta-analysis if studies at high risk of bias were excluded, and certainty of effect estimates was 'low'. No clinical utility analyses or clinical impact studies were found for any of the models. Conclusions: Models derived and/or externally validated for prediction of incident CKD in community-based EHRs demonstrate good prediction performance, but assessment of clinical usefulness is limited by high risk of bias, low certainty of evidence and a lack of impact studies.

3.
Front Pharmacol ; 15: 1378872, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38756382

RESUMO

Daptomycin is gaining prominence for the treatment of methicillin-resistant Staphylococcus aureus infections. However, the dosage selection for daptomycin in critically ill patients remains uncertain, especially in Chinese patients. This study aimed to establish the population pharmacokinetics of daptomycin in critically ill patients, optimize clinical administration plans, and recommend appropriate dosage for critically ill patients in China. The study included 64 critically ill patients. Blood samples were collected at the designated times. The blood daptomycin concentration was determined using validated liquid chromatography-tandem mass spectrometry. A nonlinear mixed-effects model was applied for the population pharmacokinetic analysis and Monte Carlo simulations of daptomycin. The results showed a two-compartment population pharmacokinetic model of daptomycin in critically ill adult Han Chinese patients. Monte Carlo simulations revealed that a daily dose of 400 mg of daptomycin was insufficient for the majority of critically ill adult patients to achieve the anti-infective target. For critically ill adult patients with normal renal function (creatinine clearance rate >90 mL/min), the probability of achieving the target only reached 90% when the daily dose was increased to 700 mg. For patients undergoing continuous renal replacement therapy (CRRT), 24 h administration of 500 mg met the pharmacodynamic goals and did not exceed the safety threshold in most patients. Therefore, considering its efficacy and safety, intravenous daptomycin doses are best scaled according to creatinine clearance, and an increased dose is recommended for critically ill patients with hyperrenalism. For patients receiving CRRT, medication is recommended at 24 h intervals.

4.
J Mol Neurosci ; 74(2): 36, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38568285

RESUMO

After ischemic stroke, microRNAs (miRNAs) participate in various processes, including immune responses, inflammation, and angiogenesis. Diabetes is a key factor increasing the risk of ischemic stroke; however, the regulatory pattern of miRNAs at different stages of diabetic stroke remains unclear. This study comprehensively analyzed the miRNA expression profiles in diabetic mice at 1, 3, and 7 days post-reperfusion following the middle cerebral artery occlusion (MCAO). We identified differentially expressed (DE) miRNAs in diabetic stroke and found significant dysregulation of some novel miRNAs (novel_mir310, novel_mir89, and novel_mir396) post-stroke. These DEmiRNAs were involved in apoptosis and the formation of tight junctions. Finally, we identified three groups of time-dependent DE miRNAs (miR-6240, miR-135b-3p, and miR-672-5p). These have the potential to serve as biomarkers of diabetic stroke. These findings provide a new perspective for future research, emphasizing the dynamic changes in miRNA expression after diabetic stroke and offering potential candidates as biomarkers for future clinical applications.


Assuntos
Diabetes Mellitus Experimental , AVC Isquêmico , MicroRNAs , Acidente Vascular Cerebral , Animais , Camundongos , Diabetes Mellitus Experimental/genética , Regulação da Expressão Gênica de Plantas , MicroRNAs/genética , Plantas Geneticamente Modificadas , Acidente Vascular Cerebral/genética , Biomarcadores
5.
Artigo em Inglês | MEDLINE | ID: mdl-38606856

RESUMO

High-dose tigecycline is gradually being introduced for the treatment of serious infectious diseases due to the increasing difficulty in treating pan-resistant bacterial infections. However, the safety of high-dose tigecycline is controversial. We report the case of a 76-year-old female patient with cerebral hemorrhage who received high-dose tigecycline (100 mg q12h) with other drugs for ventilator-associated pneumonia. 25 days after admission, she developed acute liver failure, mainly manifested by abnormally high bilirubin, coagulation dysfunction, and gastrointestinal hemorrhage with hemorrhagic shock. According to the updated Roussel Uclaf causality assessment method, the patient's acute liver injury was most likely caused by tigecycline.

6.
8.
FEBS J ; 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38661680

RESUMO

Immune checkpoint inhibitors provide a definite survival benefit for patients with driver-negative advanced non-small cell lung cancer (NSCLC), but predictors of efficacy are still lacking. There may be a relationship between immune inflammatory state and tumor immune response. We explored the relationship of serum neutrophil extracellular traps (NETs) with infiltrating cells in the tumor tissues of patients with NSCLC as well as their relationship with the therapeutic efficacy of programmed cell death protein 1 (PD-1) inhibitors. Serum myeloperoxidase (MPO)-double-stranded DNA (dsDNA) was detected as a marker of NET serum concentration. T cells were detected by immunohistochemical staining, and neutrophils were counted by MPO immunofluorescence staining. Of the 31 patients with NSCLC, a longer progression-free survival after PD-1 inhibitor treatment was associated with higher levels of CD3+ T cells, a lower neutrophil : CD3+-T-cell ratio (NEU/CD3+) and lower neutrophil : CD8+-T-cell ratio (NEU/CD8+) in tumor tissues. Patients with higher serum NETs were more likely to develop progressive disease after treatment (P = 0.003) and to have immune-related adverse events (IrAEs) as well as higher NEU/CD3+ and NEU/CD8+. The combined model of serum NETs, CD8+ T cells, and tumor proportion score (TPS) significantly improved the prediction of PD-1 inhibitor efficacy [P = 0.033; area under the curve (AUC) = 0.881]. Our results indicate that serum NETs are effective predictors of PD-1 inhibitor response and reflect the tissue neutrophil-to-lymphocyte ratio and IrAE levels. The combined model of serum NETs, CD8+ T cells, and TPS is a powerful tool for predicting the efficacy of PD-1 inhibitor treatment in patients with NSCLC.

9.
Curr Eye Res ; : 1-7, 2024 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-38679916

RESUMO

PURPOSE: This meta-analysis discusses the effectiveness of steroid intervention before vitrectomy in patients with rhegmatogenous retinal detachment associated with choroidal detachment. METHODS: We searched PubMed, MEDLINE, EMBASE, and the Cochrane Library for randomized controlled trials and observational studies published until August 2023. We included studies involving: patients with rhegmatogenous retinal detachment associated with choroidal detachment with proliferative vitreoretinopathy; an experimental group that was not administered steroids and a control group that was administered steroids; and assessment of visual acuity, retinal reattachment rate, and complications. The heterogeneity, publication bias, and sensitivity analysis were performed to ensure the statistical power and reliability of the analysis. RESULTS: Two randomized controlled trials and four case-control studies involving 490 eyes were included in the meta-analysis. There were no significant differences in the primary and final retinal reattachment rates after surgery between the steroid and non-steroid groups (primary retinal reattachment rate: odds ratio = 1.01, 95% confidence interval = 0.63-1.63, p = .41; final retinal reattachment rate: odds ratio = 0.82, 95% confidence interval = 0.43-1.59, p = .33). There was no statistically significant difference in postoperative visual acuity improvement between the two groups (odds ratio = 1.19, confidence interval = 0.63-2.25, p = .69). In addition, subgroup analyses of different types of steroids showed that systemic and local administration of steroids had similar results for retinal reattachment rate and visual acuity improvement. CONCLUSION: Patients with rhegmatogenous retinal detachment associated with choroidal detachment who did not receive preoperative steroids achieved the same effect as patients with rhegmatogenous retinal detachment associated with choroidal detachment who did receive preoperative steroids in terms of retinal reattachment rate and visual acuity. It is recommended that patients with rhegmatogenous retinal detachment associated with choroidal detachment undergo surgery as promptly as possible.

10.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 41(2): 304-312, 2024 Apr 25.
Artigo em Chinês | MEDLINE | ID: mdl-38686411

RESUMO

The effect of neutrophil extracellular traps (NETs) on promoting intravascular microthrombi formation and exacerbating the severity of sepsis in patients has gained extensive attention. However, in sepsis, the mechanisms and key signaling molecules mediating NET formation during direct interactions of endothelial cells and neutrophils still need further explored. Herein, we utilized lipoteichoic acid (LTA), a component shared by Gram-positive bacteria, to induce NET extrusion from neutrophils firmly adhered to the glass slides coated with intercellular adhesion molecule-1(ICAM-1). We also used Sytox green to label NET-DNA and Flou-4 AM as the intracellular Ca 2+ signaling indicator to observe the NET formation and fluctuation of Ca 2+ signaling. Our results illustrated that LTA was able to induce NET release from neutrophils firmly attached to ICAM-1-coated glass slides, and the process was time-dependent. In addition, our study indicated that LTA-induced NET release by neutrophils stably adhered to ICAM-1 depended on Ca 2+ signaling but not intracellular reactive oxygen species (ROS). This study reveals NET formation mediated by direct interactions between endothelial ICAM-1 and neutrophils under LTA stimulation and key signaling molecules involved, providing the theoretical basis for medicine development and clinical treatment for related diseases.


Assuntos
Armadilhas Extracelulares , Molécula 1 de Adesão Intercelular , Lipopolissacarídeos , Neutrófilos , Ácidos Teicoicos , Ácidos Teicoicos/farmacologia , Molécula 1 de Adesão Intercelular/metabolismo , Neutrófilos/metabolismo , Armadilhas Extracelulares/metabolismo , Humanos , Espécies Reativas de Oxigênio/metabolismo , Sinalização do Cálcio , Adesão Celular , Sepse/metabolismo , Células Endoteliais/metabolismo , Células Endoteliais/citologia
11.
Gerontology ; 70(5): 491-498, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38479368

RESUMO

INTRODUCTION: We analyzed the effect of dexmedetomidine (DEX) as a local anesthetic adjuvant on postoperative delirium (POD) in elderly patients undergoing elective hip surgery. METHODS: In this study, 120 patients undergoing hip surgery were enrolled and randomly assigned to two groups: fascia iliaca compartment block with DEX + ropivacaine (the Y group, n = 60) and fascia iliaca compartment block with ropivacaine (the R group, n = 60). The primary outcomes: presence of delirium during the postanesthesia care unit (PACU) period and on the first day (D1), the second day (D2), and the third day (D3) after surgery. The secondary outcomes: preoperative and postoperative C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR), occurrence of insomnia on the preoperative day, day of operation, D1 and D2; HR values of patients in both groups before iliac fascia block (T1), 30 min after iliac fascia block (T2), at surgical incision (T3), 20 min after incision (T4), when they were transferred out of the operating room (T5) and after leaving the recovery room (T6) at each time point; VAS for T1, PACU, D1, D2; the number of patients requiring remedial analgesics within 24 h after blockade and related complications between the two groups. RESULTS: A total of 97 patients were included in the final analysis, with 11 and 12 patients withdrawing from the R and Y groups, respectively. The overall incidence of POD and its incidence in the PACU and ward were all lesser in the Y group than in the R group (p < 0.05). Additionally, fewer cases required remedial analgesia during the PACU period, and more vasoactive drugs were used for maintaining circulatory system stability in the Y group as compared to the R group (p < 0.05). At the same time, the incidence of intraoperative and postoperative bradycardia in the Y group was higher than that in the R group, accompanied by lower postoperative CRP and ESR (all p < 0.05). CONCLUSION: Ultrasound-guided high fascia iliaca compartment block with a combination of ropivacaine and DEX can reduce the incidence of POD, the use of intraoperative opioids and postoperative remedial analgesics, and postoperative inflammation in elderly patients who have undergone hip surgery, indicating that this method could be beneficial in the prevention and treatment of POD.


Assuntos
Anestésicos Locais , Dexmedetomidina , Procedimentos Cirúrgicos Eletivos , Bloqueio Nervoso , Ropivacaina , Humanos , Dexmedetomidina/administração & dosagem , Masculino , Idoso , Feminino , Anestésicos Locais/administração & dosagem , Bloqueio Nervoso/métodos , Ropivacaina/administração & dosagem , Procedimentos Cirúrgicos Eletivos/efeitos adversos , Procedimentos Cirúrgicos Eletivos/métodos , Fáscia , Idoso de 80 Anos ou mais , Delírio do Despertar/prevenção & controle , Delírio do Despertar/epidemiologia , Complicações Pós-Operatórias/prevenção & controle , Complicações Pós-Operatórias/epidemiologia , Quadril/cirurgia , Artroplastia de Quadril/efeitos adversos , Artroplastia de Quadril/métodos
12.
Am Heart J ; 272: 1-10, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38458372

RESUMO

BACKGROUND: The increasing burden of atrial fibrillation (AF) emphasizes the need to identify high-risk individuals for enrolment in clinical trials of AF screening and primary prevention. We aimed to develop prediction models to identify individuals at high-risk of AF across prediction horizons from 6-months to 10-years. METHODS: We used secondary-care linked primary care electronic health record data from individuals aged ≥30 years without known AF in the UK Clinical Practice Research Datalink-GOLD dataset between January 2, 1998 and November 30, 2018; randomly divided into derivation (80%) and validation (20%) datasets. Models were derived using logistic regression from known AF risk factors for incident AF in prediction periods of 6 months, 1-year, 2-years, 5-years, and 10-years. Performance was evaluated using in the validation dataset with bootstrap validation with 200 samples, and compared against the CHA2DS2-VASc and C2HEST scores. RESULTS: Of 2,081,139 individuals in the cohort (1,664,911 in the development dataset, 416,228 in the validation dataset), the mean age was 49.9 (SD 15.4), 50.7% were women, and 86.7% were white. New cases of AF were 7,386 (0.4%) within 6 months, 15,349 (0.7%) in 1 year, 38,487 (1.8%) in 5 years, and 79,997 (3.8%) by 10 years. Valvular heart disease and heart failure were the strongest predictors, and association of hypertension with AF increased at longer prediction horizons. The optimal risk models incorporated age, sex, ethnicity, and 8 comorbidities. The models demonstrated good-to-excellent discrimination and strong calibration across prediction horizons (AUROC, 95%CI, calibration slope: 6-months, 0.803, 0.789-0.821, 0.952; 1-year, 0.807, 0.794-0.819, 0.962; 2-years, 0.815, 0.807-0.823, 0.973; 5-years, 0.807, 0.803-0.812, 1.000; 10-years 0.780, 0.777-0.784, 1.010), and superior to the CHA2DS2-VASc and C2HEST scores. The models are available as a web-based FIND-AF calculator. CONCLUSIONS: The FIND-AF models demonstrate high discrimination and calibration across short- and long-term prediction horizons in 2 million individuals. Their utility to inform trial enrolment and clinical decisions for AF screening and primary prevention requires further study.


Assuntos
Fibrilação Atrial , Humanos , Fibrilação Atrial/epidemiologia , Fibrilação Atrial/complicações , Feminino , Masculino , Pessoa de Meia-Idade , Medição de Risco/métodos , Reino Unido/epidemiologia , Incidência , Fatores de Risco , Idoso , Adulto
14.
Cancer Manag Res ; 16: 151-161, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38501053

RESUMO

Purpose: Immune checkpoint inhibitors (ICIs) have significantly improved the outcomes of patients with cancer; however, these agents may initiate immune-related adverse events (irAEs). Previous studies have demonstrated a robust correlation between disease prognosis and the occurrence of irAEs, specifically skin or endocrine irAEs. Herein, we aimed to evaluate the correlation between irAE-related adrenal insufficiency (AI) and ICI treatment efficacy. Patients and methods: Patients diagnosed with gastrointestinal, respiratory, head and neck, urological, skin and gynecologic cancers treated with anti-programmed cell death 1 (PD-1)/anti-programmed cell death ligand 1 (PD-L1) antibody as monotherapy or combined therapy (combined with chemotherapy or targeted therapy) were divided into irAE-A (patients with irAE-related AI), irAE-B (patients with other irAEs) and non-irAE groups. Immunotherapy efficacy was assessed based on the disease control rate (DCR), progression-free survival (PFS), and overall survival (OS). Survival probabilities were estimated using the Kaplan-Meier method with the log-rank test. Results: Of the 192 patients enrolled in our study, 17 developed irAE-related AI and 83 developed other irAEs. The DCR of the irAE-A and irAE-B groups were higher than that of the non-irAE group (P<0.05). Multiple extended Cox regression analyses showed that irAE status (irAE-A vs non-irAE, P=0.008; irAE-B vs non-irAE, P=0.020), Eastern Cooperative Oncology Group (ECOG) status (P=0.045), tumor-node-metastasis (TNM) stage (P=0.000), and treatment line (P=0.002) were independent predictors of PFS. Contrarily, irAE status (irAE-A vs non-irAE, P=0.009; irAE-B vs non-irAE, P=0.013), ECOG status (P=0.007), TNM stage (P=0.035), treatment line (P=0.001) and treatment modality (P=0.008) were independent predictors for OS. Conclusion: IrAE-related AI was significantly associated with ICI treatment efficacy in patients with cancer, which could be a potentially predictable marker. Due to the destruction of adrenal tissue by T cells with enhanced activity, AI reflects enhanced T cell activity to some extent.

15.
Sci Prog ; 107(1): 368504231213430, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38545795

RESUMO

Intelligent monitoring of environmental information in ships is an important prerequisite for reducing and avoiding accidents and is of great importance for safety at sea. The use of a ship environmental monitoring system based on wireless sensor networks has the unique advantages of low cost, stability, and reliability, allowing real-time monitoring of many environmental factors in ships. This article proposes an optimal topology control to maximize collected data satisfaction and reduce energy consumption and transmission latency. First, the cluster head selection method is obtained by initializing the wireless sensor network with a fuzzy clustering algorithm, then the amount of collection data is obtained by a sub-gradient descent algorithm, and a sensor association scheme based on ant colony optimization is proposed to solve the knapsack problem. Finally, simulation results show that the proposed algorithm in this article can effectively reduce the energy consumption and transmission delay of the wireless sensor network while ensuring the monitoring of the grounding protection in the electrical system of the offshore ship.

16.
Heliyon ; 10(6): e27346, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38515731

RESUMO

Candida albicans (C. albicans) is one of the most common clinical isolates of systemic fungal infection. Long-term and inappropriate use of antifungal drugs can cause fungal resistance, which poses a great challenge to the clinical treatment of fungal infections. The combination of antifungal drugs and non-antifungal drugs to overcome the problem of fungal resistance has become a research hotspot in recent years. Our previous study found that the combination of rifapentine (RFT) and fluconazole (FLC) has a significant synergistic against FLC-resistant C. albicans. The present study aimed to further verify the synergistic effect between FLC and RFT against the FLC-resistant C. albicans 100, and explore the underlying mechanism. The growth curve and spot assay test not only showed the synergistic effect of FLC and RFT on FLC-resistant C. albicans in vitro but exhibited a dose-dependent effect on RFT, indicating that RFT may play a principal role in the synergic effect of the two drugs. Flow cytometry showed that the combined use of RFT and FLC arrested cells in the G2/M phase, inhibiting the normal division and proliferation of FLC-resistant C. albicans. Transmission electron microscopy (TEM) demonstrated that FLC at a low concentration could still cause a certain degree of damage to the cell membrane in the FLC-resistant C. albicans, as represented by irregular morphologic changes and some defects observed in the cell membrane. When FLC was used in combination with RFT, the nuclear membrane was dissolved and the nucleus was condensed into a mass. Detection of the intracellular drug concentration of fungi revealed that the intracellular concentration of RFT was 31-195 fold that of RFT alone when it was concomitantly used with FLC. This indicated that FLC could significantly increase the concentration of RFT in cells, which may be due to the damage caused to the fungal cell membrane by FLC. In short, the present study revealed a synergistic mechanism in the combined use of RFT and FLC, which may provide a novel strategy for the clinical treatment of FLC-resistant C. albicans.

17.
Sci Rep ; 14(1): 6075, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38480850

RESUMO

The two-phase compression process in the rotary compressor often occurs, such as defrosting and startup processes, which has a significant impact on the performance and reliability of air conditioning systems. In this paper, the CFD simulations predicting the two-phase refrigerant compression process in the compressor cylinder are conducted using the commercial software ANSYS Fluent. The dynamic mesh for the fluid domain and phase change model for the refrigerant are considered in the simulation. Effects of initial liquid volume fraction, refrigerant type and compressor type on the two-phase compression characteristics using R290 as refrigerant are carried out. Variations of the pressure, temperature, gas fraction distribution and evaporation rate in the cylinder are discussed. The results show that most liquid accumulates near the leakage gap and the bottom of the compression chamber during the two-phase compression process. The peak pressure during the two-phase compression decreases with the increase of the liquid volume fraction. The evaporation rate of R32 in the cylinder is much higher than that of R290. The maximum pressure of the reciprocating compressor is 2.26 times higher than that of the rotary compressor.

18.
Adv Healthc Mater ; : e2304130, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38427696

RESUMO

P-glycoprotein (P-gp)-mediated multidrug resistance (MDR) often leads to the failure of antitumor chemotherapy, and codelivery of chemodrug with P-gp siRNA (siP-gp) represents a promising approach for treating chemoresistant tumors. To maximize the antitumor efficacy, it is desired that the chemodrug be latently released upon completion of siP-gp-mediated gene silencing, which however, largely remains an unmet demand. Herein, core-shell nanocomplexes (NCs) are developed to overcome MDR via staged liberation of siP-gp and chemodrug (doxorubicin, Dox) in hierarchical response to reactive oxygen species (ROS) concentration gradients. The NCs are constructed from mesoporous silica nanoparticles (MSNs) surface-decorated with cRGD-modified, PEGylated, ditellurium-crosslinked polyethylenimine (RPPT), wherein thioketal-linked dimeric doxorubicin (TK-Dox2 ) and photosensitizer are coencapsulated inside MSNs while siP-gp is embedded in the RPPT polymeric layer. RPPT with ultrahigh ROS-sensitivity can be efficiently degraded by the low-concentration ROS inside cancer cells to trigger siP-gp release. Upon siP-gp-mediated gene silencing and MDR reversal, light irradiation is performed to generate high-concentration, lethal amount of ROS, which cleaves thioketal with low ROS-sensitivity to liberate the monomeric Dox. Such a latent release profile greatly enhances Dox accumulation in Dox-resistant cancer cells (MCF-7/ADR) in vitro and in vivo, which cooperates with the generated ROS to efficiently eradicate MCF-7/ADR xenograft tumors.

19.
Hum Mov Sci ; 95: 103213, 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38520896

RESUMO

BACKGROUND: Individuals with Down syndrome (DS) walk with altered gait patterns compared to their typically developing (TD) peers. While walking at faster speeds and with external ankle load, preadolescents with DS demonstrate spatiotemporal and kinetic improvements. However, evidence of joint kinematic adjustments is unknown, which is imperative for targeted rehabilitation design. RESEARCH QUESTION: How does increasing walking speed and adding ankle load affect the joint kinematics of children with and without DS during overground walking? METHODS: In this cross-sectional observational study, thirteen children with DS aged 7-11 years and thirteen age- and sex-matched TD children completed overground walking trials. There were two speed conditions: normal speed and fast speed (as fast as possible without running). There were two load conditions: no load and ankle load (2% of body mass added bilaterally above the ankle). A motion capture system was used to register the ankle, knee, and hip joint angles in the sagittal plane. Peak flexion/extension angles, range of motion, and timing of peak angles were identified. In addition, statistical parametric mapping (SPM) was conducted to evaluate the trajectory of the ankle, knee, and hip joint angles across the entire gait cycle. RESULTS AND SIGNIFICANCE: SPM analysis revealed the DS group walked with greater ankle, knee, and hip flexion compared to the TD group for most of the gait cycle, regardless of condition. Further, increasing walking speed led to improved ankle joint kinematics in both groups by shifting peak plantarflexion closer to toe-off. However, knee extension during stance was challenged in the DS group. Adding ankle load improved hip and knee kinematics in both groups but reduced peak plantarflexion around toe-off. The kinematic adjustments in the DS group suggest specific motor strategies to accommodate their neuromuscular deficits, which can provide a foundation to design targeted gait-based interventions for children with DS.

20.
Environ Res ; 251(Pt 2): 118699, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38493861

RESUMO

The global public health concern of nitrate (NO3-) contamination in groundwater is particularly pronounced in irrigated agricultural regions. This paper aims to analyze the spatial distribution of groundwater NO3-, assess potential health risks for local residents, and quantitatively identify nitrate sources during different seasons and land use types in the Jinghuiqu Irrigation District, a region in northwestern China with a longstanding agricultural history. The investigation utilizes hydrochemical parameters, dual isotopic data, and the Bayesian stable isotope mixing model (MixSIAR). The findings underscore significant seasonal variations in the average concentrations of NO3-, with values of 87.72 mg/L and 101.87 mg/L during the wet and dry seasons, respectively. Furthermore, distinct fluctuations in nitrate concentration were observed across different land use types, whereby vegetable lands manifested the maximum concentration. Prolonged exposure to elevated nitrate concentrations may pose potential health risks to residents, especially in the dry season when the non-carcinogenic groundwater nitrate risk surges past its wet season counterpart. The MixSIAR analysis revealed that chemical fertilizers accounted for the majority of nitrate pollution in vegetable lands, both during the dry season (49.6%) and wet season (41.2%). In contrast, manure and sewage contributed significantly to NO3-concentrations in residential land during the wet (74.9%) and dry seasons (67.6%). For croplands, soil nitrogen emerged as a dominant source during the wet season (42.2%), while chemical fertilizers prevailed in the dry season (38.7%). In addition to source variations, the nitrate concentration of groundwater is further affected by hydrogeological conditions, with more permeable aquifers tending to display higher nitrate concentrations. Thus, targeted measures were proposed to modify or impede the nitrogen migration pathway, taking into consideration hydrogeological conditions and incorporating domestic sewage, organic fertilizer, and agricultural management practices.

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