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1.
Reprod Domest Anim ; 59(4): e14566, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38627959

RESUMO

Early pregnancy loss is a primary cause of low reproductive rates in dairy cows, posing severe economic losses to dairy farming. The accurate diagnosis of dairy cows with early pregnancy loss allows for oestrus synchronization, shortening day open, and increasing the overall conception rate of the herd. Several techniques are available for detecting early pregnancy loss in dairy cows, including rectal ultrasound, circulating blood progesterone, and pregnancy-associated glycoproteins (PAGs). Yet, there is a need to improve on existing techniques and develop novel strategies to identify cows with early pregnancy loss accurately. This manuscript reviews the applications of rectal ultrasound, circulating blood progesterone concentration, and PAGs in the diagnosis of pregnancy loss in dairy cows. The manuscript also discusses the recent progress of new technologies, including colour Doppler ultrasound (CDUS), interferon tau-induced genes (ISGs), and exosomal miRNA in diagnosing pregnancy loss in dairy cows. This study will provide an option for producers to re-breed cows with pregnancy loss, thereby reducing the calving interval and economic costs. Meanwhile, this manuscript might also act as a reference for exploring more economical and precise diagnostic technologies for early pregnancy loss in dairy cows.


Assuntos
Doenças dos Bovinos , Progesterona , Gravidez , Feminino , Bovinos , Animais , Aborto Animal/diagnóstico , Reprodução , Fertilização , Glicoproteínas , Inseminação Artificial/veterinária , Doenças dos Bovinos/diagnóstico
2.
Phys Rev E ; 109(3-1): 034701, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38632774

RESUMO

Self-oscillating systems possess the ability to convert ambient energy directly into mechanical work, and new types of self-oscillating systems are worth designing for practical applications in energy harvesters, engines and actuators. Taking inspiration from the four-stroke engine. A concept for a self-rotating engine is presented on the basis of photothermally responsive materials, consisting of a liquid crystal elastomer (LCE) fiber, a hinge and a turnplate, which can self-rotate under steady illumination. Based on the photo-thermal-mechanical model, a nonlinear theoretical model of the LCE-based engine under steady illumination is proposed to investigate its self-rotating behaviors. Numerical calculations reveal that the LCE-based engine experiences a supercritical Hopf bifurcation between the static regime and the self-rotation regime. The self-rotation of the LCE-based engine originates from the photothermally driven strain of the LCE fiber in illumination, and its continuous periodic motion is sustained by the correlation between photothermal energy and damping dissipation. The Hopf bifurcation conditions are also explored in detail, as well as the vital system parameters affecting self-rotation frequency. Compared to the abundant existing self-oscillating systems, this conceptual self-rotating LCE-based engine stands out due to its simple and lightweight structure, customizable dimensions and high speed, and it is expected to offer a broader range of design concepts applicable to soft robotics, energy harvesters, medical instruments, and so on.

3.
Front Endocrinol (Lausanne) ; 15: 1309082, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38606086

RESUMO

Purpose: This study aims to investigate the relationship between the total muscle-to-fat ratio (tMFR) and female urinary incontinence (UI), determine whether tMFR can serve as a useful index for predicting UI, and identify factors that may influence this relationship. Methods: We retrospectively analyzed data from 4391 adult women participating in the National Health and Nutrition Examination Survey (NHANES) conducted between 2011 and 2018. The correlation between tMFR and UI was examined using a dose-response curve generated through a restricted cubic spline (RCS) function, LASSO and multivariate logistic regression. Furthermore, predictive models were constructed incorporating factors such as age, race, hypertension, diabetes, cotinine levels, and tMFR. The performance of these predictive models was evaluated using training and test datasets, employing calibration curves, receiver operating characteristic curves, and clinical decision curves. Mediation effects were also analyzed to explore potential relationships between tMFR and female UI. Results: In a sample of 4391 adult women, 1073 (24.4%) self-reported experiencing UI, while 3318 (75.6%) reported not having UI. Based on the analyses involving LASSO regression and multivariate logistic regression, it was found that tMFR exhibited a negative association with UI (OR = 0.599, 95% CI: 0.497-0.719, P < 0.001). The results from the restricted cubic spline chart indicated a decreasing risk of UI in women as tMFR increased. Furthermore, the model constructed based on logistic regression analysis demonstrated a certain level of accuracy (in the training dataset: area under the curve (AUC) = 0.663; in the test dataset: AUC = 0.662) and clinical applicability. The mediation analysis revealed that the influence of tMFR on the occurrence of UI in women might potentially occur through the blood index lymphocyte count (P = 0.040). Conclusion: A high tMFR serves as a protective factor against UI in women. Furthermore, lymphocyte might be involved in the relationship between tMFR and female UI.


Assuntos
Incontinência Urinária , Adulto , Humanos , Feminino , Estados Unidos/epidemiologia , Inquéritos Nutricionais , Estudos Retrospectivos , Incontinência Urinária/diagnóstico , Incontinência Urinária/epidemiologia , Músculos , Curva ROC
4.
J Hazard Mater ; 470: 134249, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38603909

RESUMO

In cold regions, microplastics (MPs) in the soil undergo freeze-thaw (FT) aging process. Little is known about how FT aged MPs influence soil physico-chemical properties and microbial communities. Here, two environmentally relevant concentrations (50 and 500 mg/kg) of 50 and 500 µm polyethylene (PE) and polypropylene (PP) MPs treated soils were subjected to 45-day FT cycles (FTCs). Results showed that MPs experienced surface morphology, hydrophobicity and crystallinity alterations after FTCs. After 45-day FTCs, the soil urease (SUE) activity in control (MPs-free group that underwent FTCs) was 33.49 U/g. SUE activity in 50 µm PE group was reduced by 19.66 %, while increased by 21.16 % and 37.73 % in 500 µm PE and PP groups compared to control. The highest Shannon index was found in 50 µm PP-MPs group at 50 mg/kg, 2.26 % higher than control (7.09). Compared to control (average weighted degree=8.024), all aged MPs increased the complexity of network (0.19-1.43 %). Bacterial biomarkers of aged PP-MPs were associated with pollutant degradation. Aged PP-MPs affected genetic information, cellular processes, and disrupted the biosynthesis of metabolites. This study provides new insights into the potential hazards of MPs after FTCs on soil ecosystem in cold regions.

5.
Z Gastroenterol ; 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38604219

RESUMO

Carrilizumab, a PD-1 inhibitor, has shown therapeutic effectiveness in patients with late-stage or metastatic solid tumors exhibiting DNA mismatch repair deficiency (dMMR) or microsatellite instability-high (MSI-H). dMMR/MSI-H cancer patients are known to be responsive to PD-1 inhibitors. However, the use of carrilizumab for preoperative immunotherapy in early, unresectable MSI-H/dMMR primary colon cancer lesions is relatively underexplored. We present the case of a 46-year-old male who sought medical attention at our institution due to a history of hematochezia for two weeks, right-sided abdominal pain for one week, and loose stools. Imaging indicated duodenal involvement, and a biopsy confirmed ascending colon adenocarcinoma with MSI-H status. Given that the patient's family exhibited a history of more than three confirmed cases of colorectal cancer spanning two generations, Lynch syndrome was considered. After four cycles of PD-1 antagonist immunotherapy with carrilizumab, the patient's symptoms resolved, and physical examination revealed no abdominal tenderness or palpable masses. Following radical colectomy, the primary tumor exhibited a pathological complete response. This case highlights the potential of preoperative neoadjuvant immunotherapy to improve staging accuracy and increase surgical resection rates in T4b MSI-H colon cancer patients without distant metastasis, suggesting a need for reconsideration of the treatment approach.

6.
Transl Androl Urol ; 13(3): 383-396, 2024 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-38590969

RESUMO

Background: Papillary renal neoplasm with reverse polarity (PRNRP) is a novel entity with unique clinicopathological characteristics, and only a small number of patients with PRNRP have been described. Methods: We retrospectively analyzed the data for nine patients with PRNRP and evaluated differences in the clinical, histomorphological, immunohistochemical, and molecular features; prognosis; and differential diagnosis of PRNRP from other renal tumors with papillary structure. Results: There were six males and three females aged 36 to 74 years (mean: 62.33 years; median: 68 years). All the tumors were solitary and ranged from 1 to 3.7 cm (mean: 2.17 cm; median: 2 cm), with three and six tumors arose in the left and right renal tract, respectively. Pathologically, PRNRP is a small, well-circumscribed neoplasm with predominant papillary formations. The lining epithelium is composed of a monolayer of cuboidal to low-columnar cells with low-grade nuclei arranged against the apical pole of the tumor cells. Edema, mucinous degeneration, and hyaline degeneration are found in the fibrovascular cores. Foamy macrophages, psammoma bodies, hemosiderin deposition, and infiltrative tumor boundaries were present in some patients. Immunohistochemically, all tumors showed diffuse positive staining for GATA3. Sanger sequencing confirmed the presence of KRAS mutation in seven patients. All patients had a good prognosis after surgery and were relapse free. Positive staining for GATA3 and negative staining for vimentin were the most significant markers for differentiating PRNRP from other renal tumors with analogous structure. Conclusions: These findings suggested that PRNRP is a distinctive subtype of renal tumor with specific pathological features and indolent behaviors that should be distinguished from other renal tumors, especially papillary renal cell carcinoma. A monolayer of tumor cells with an inverted nuclear pattern, positive staining for GATA3, and KRAS mutation are essential for pathological diagnosis. Owing to its satisfactory prognosis, the surveillance and follow-up of patients with PRNRP should be additionally formulated.

7.
PLoS Pathog ; 20(4): e1012169, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38640137

RESUMO

Integrative and conjugative elements (ICEs) play a vital role in bacterial evolution by carrying essential genes that confer adaptive functions to the host. Despite their importance, the mechanism underlying the stable inheritance of ICEs, which is necessary for the acquisition of new traits in bacteria, remains poorly understood. Here, we identified SezAT, a type II toxin-antitoxin (TA) system, and AbiE, a type IV TA system encoded within the ICESsuHN105, coordinately promote ICE stabilization and mediate multidrug resistance in Streptococcus suis. Deletion of SezAT or AbiE did not affect the strain's antibiotic susceptibility, but their duple deletion increased susceptibility, mainly mediated by the antitoxins SezA and AbiEi. Further studies have revealed that SezA and AbiEi affect the genetic stability of ICESsuHN105 by moderating the excision and extrachromosomal copy number, consequently affecting the antibiotic resistance conferred by ICE. The DNA-binding proteins AbiEi and SezA, which bind palindromic sequences in the promoter, coordinately modulate ICE excision and extracellular copy number by binding to sequences in the origin-of-transfer (oriT) and the attL sites, respectively. Furthermore, AbiEi negatively regulates the transcription of SezAT by binding directly to its promoter, optimizing the coordinate network of SezAT and AbiE in maintaining ICESsuHN105 stability. Importantly, SezAT and AbiE are widespread and conserved in ICEs harbouring diverse drug-resistance genes, and their coordinated effects in promoting ICE stability and mediating drug resistance may be broadly applicable to other ICEs. Altogether, our study uncovers the TA system's role in maintaining the genetic stability of ICE and offers potential targets for overcoming the dissemination and evolution of drug resistance.

8.
J Alzheimers Dis ; 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38640153

RESUMO

Background: We previously demonstrated the validity of a regression model that included ethnicity as a novel predictor for predicting normative brain volumes in old age. The model was optimized using brain volumes measured with a standard tool FreeSurfer. Objective: Here we further verified the prediction model using newly estimated brain volumes from Neuro I, a quantitative brain analysis system developed for Korean populations. Methods: Lobar and subcortical volumes were estimated from MRI images of 1,629 normal Korean and 786 Caucasian subjects (age range 59-89) and were predicted in linear regression from ethnicity, age, sex, intracranial volume, magnetic field strength, and scanner manufacturers. Results: In the regression model predicting the new volumes, ethnicity was again a substantial predictor in most regions. Additionally, the model-based z-scores of regions were calculated for 428 AD patients and the matched controls, and then employed for diagnostic classification. When the AD classifier adopted the z-scores adjusted for ethnicity, the diagnostic accuracy has noticeably improved (AUC = 0.85, ΔAUC = + 0.04, D = 4.10, p <  0.001). Conclusions: Our results suggest that the prediction model remains robust across different measurement tool, and ethnicity significantly contributes to the establishment of norms for brain volumes and the development of a diagnostic system for neurodegenerative diseases.

9.
Org Lett ; 26(15): 3213-3217, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38573591

RESUMO

With in-depth research on 1,2-difunctionalization, remote difunctionalization has garnered widespread attention for achieving multifunctionality. Herein, we report a strategy for achieving remote difunctionalization under mild conditions. This strategy exhibited good substrate suitability and functional group tolerance. In addition, the significance of this method is further evidenced by its successful application in scaling up and conducting additional transformations of target compounds. Mechanistic studies showed that a radical might be involved in this process.

10.
Heliyon ; 10(4): e26405, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38434063

RESUMO

Alzheimer's disease(AD) poses a significant challenge due to its widespread prevalence and the lack of effective treatments, highlighting the urgent need for early detection. This research introduces an enhanced neural network, named ADnet, which is based on the VGG16 model, to detect Alzheimer's disease using two-dimensional MRI slices. ADNet incorporates several key improvements: it replaces traditional convolution with depthwise separable convolution to reduce model parameters, replaces the ReLU activation function with ELU to address potential issues with exploding gradients, and integrates the SE(Squeeze-and-Excitation) module to enhance feature extraction efficiency. In addition to the primary task of MRI feature extraction, ADnet is simultaneously trained on two auxiliary tasks: clinical dementia score regression and mental state score regression. Experimental results demonstrate that compared to the baseline VGG16, ADNet achieves a 4.18% accuracy improvement for AD vs. CN classification and a 6% improvement for MCI vs. CN classification. These findings highlight the effectiveness of ADnet in classifying Alzheimer's disease, providing crucial support for early diagnosis and intervention by medical professionals. The proposed enhancements represent advancements in neural network architecture and training strategies for improved AD classification.

11.
Mol Neurobiol ; 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38556567

RESUMO

This study investigates the role and molecular mechanism of EZH2 in glioma cell proliferation, invasion, and migration. EZH2, miR-142-3p, lncRNA KCNQ1OT1, LIN28B, and HMGB3 expressions in glioma tissues and cells were determined using qRT-PCR or Western blot, followed by CCK-8 assay detection of cell viability, Transwell detection of invasion and migration, ChIP analysis of the enrichment of EZH2 and H3K27me3 on miR-142-3p promoter, dual-luciferase reporter assay and RIP validation of the binding of miR-142-3p-KCNQ1OT1 and KCNQ1OT1-LIN28B, and actinomycin D detection of KCNQ1OT1 and HMGB3 mRNA stability. A nude mouse xenograft model and a lung metastasis model were established. EZH2, KCNQ1OT1, LIN28B, and HMGB3 were highly expressed while miR-142-3p was poorly expressed in gliomas. EZH2 silencing restrained glioma cell proliferation, invasion, and migration. EZH2 repressed miR-142-3p expression by elevating the H3K27me3 level. miR-142-3p targeted KCNQ1OT1 expression, and KCNQ1OT1 bound to LIN28B to stabilize HMGB3 mRNA, thereby promoting its protein expression. EZH2 silencing depressed tumor growth and metastasis in nude mice via the miR-142-3p/KCNQ1OT1/HMGB3 axis. In conclusion, EZH2 curbed miR-142-3p expression, thereby relieving the inhibition of KCNQ1OT1 expression by miR-142-3p, enhancing the binding of KCNQ1OT1 to LIN28B, elevating HMGB3 expression, and ultimately accelerating glioma cell proliferation, invasion, and migration.

12.
Biochem Biophys Res Commun ; 709: 149760, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38554602

RESUMO

BACKGROUND: Diabetic retinopathy (DR) is a retinal microvascular complication caused by hyperglycemia, which can lead to visual impairment or blindness. Pyroptosis is a type of inflammation-related programmed cell death, activated by caspase-1, resulting in the maturation of IL-1ß and IL-18 and the rupture of the cell membrane. RNA sequencing (RNA-seq) is a high-throughput sequencing technique that reveals the presence and quantity of RNA in the genome at a specific time point, i.e., the transcriptome. RNA-seq can analyze gene expression levels, splicing variants, mutations, fusions, editing and other post-transcriptional modifications, as well as gene expression differences between different samples or conditions. It has been widely used in biological and medical research, clinical diagnosis and new drug development. This study aimed to establish an in vitro model of diabetic retinopathy by culturing human retinal endothelial cells (HREC) with high glucose (30 mmol/L), and to detect their transcriptome expression by RNA-seq, screen for key genes related to pyroptosis, and validate the sequencing results by subsequent experiments. METHODS: We used RNA-seq to detect the transcriptome expression differences between HREC cells cultured with high glucose and control group, and identified differentially expressed genes by GO/KEGG analysis. We constructed a PPI network and determined the key genes by Cytoscape software and CytoHubba plugin. We validated the expression of related factors by Western Blot, qPCR and ELISA. RESULTS: We performed GO and KEGG analysis on the RNA-seq data and found differentially expressed genes. We used Cytoscape and CytoHubba plugin to screen out IRF1 as the key gene, and then detected the expression of IRF1 in HREC under high glucose and control group by Western Blot and qPCR. We found that the expression of Caspase-1, GSDMD and IL-1ß proteins in HREC under high glucose increased, while the expression of these proteins decreased after the inhibition of IRF1 by siRNA. ELISA showed that the secretion of IL-1ß in HREC under high glucose increased, while the inhibition of IRF1 reduced the secretion of IL-1ß. These results indicate that IRF1 plays an important role in DR, and provides a new target and strategy for the prevention and treatment of this disease.


Assuntos
Diabetes Mellitus , Retinopatia Diabética , Humanos , Retinopatia Diabética/genética , Retinopatia Diabética/metabolismo , Células Endoteliais/metabolismo , Piroptose/genética , Perfilação da Expressão Gênica/métodos , Glucose/metabolismo , Caspases/metabolismo , Diabetes Mellitus/metabolismo , Fator Regulador 1 de Interferon/genética
13.
Int J Antimicrob Agents ; 63(5): 107152, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38513747

RESUMO

INTRODUCTION: Ceftazidime-avibactam (CAZ-AVI) is a new option to treat KPC- and OXA-48 carbapenem-resistant Klebsiella pneumoniae (CRKP) infections. However, clinical evidence is limited regarding its use in treating CRKP infections, especially in solid organ transplantation (SOT) recipients. In this study, we assessed the efficacy of CAZ-AVI in treating CRKP infections in both the general population and the SOT recipients in comparison with other antibiotic regimens. METHODS: This is a single-centre retrospective cohort study of patients admitted between January 1, 2018 and June 30, 2021 with the diagnosis of CRKP infections receiving either CAZ-AVI or other regimens ≥ 72 hours and clinical outcomes were analysed. RESULTS: Of 200 patients with CRKP infections, 67 received CAZ-AVI, 133 received other regimens, and 50 were SOT recipients. In the SOT cohort, 30 patients received CAZ-AVI, and 20 received other regimens. The overall 30-day mortality was 38% in the SOT cohort. Compared with patients receiving other regimens, CAZ-AVI therapy resulted in lower 30-day mortality (23.3% vs. 60%, P = 0.014) and 90-day mortality (35.7% vs. 86.7%, P = 0.003), higher clinical cure (93.3% vs. 40%, P < 0.001) and microbiological clearance. Similar promising results of CAZ-AVI were also shown in the whole population cohort. Moreover, clinical outcomes of SOT recipients receiving CAZ-AVI were not inferior to those without SOT. CONCLUSIONS: CAZ-AVI therapy was associated with better clinical outcomes in CRKP infections in both the general population and SOT recipients. Considering the limitations of the present study, well-conducted RCTs are still warranted to confirm these findings.

14.
Fa Yi Xue Za Zhi ; 40(1): 43-49, 2024 Feb 25.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-38500460

RESUMO

OBJECTIVES: To analyze the high risk factors of obstetric brachial plexus palsy (OBPP), and to explore how to evaluate the relationship between fault medical behavior and OBPP in the process of medical damage forensic identification. METHODS: A retrospective analysis was carried out on 25 cases of medical damage liability disputes related to OBPP from 2017 to 2021 in Beijing Fayuan Judicial Science Evidence Appraisal Center. The shortcomings of hospitals in birth weight assessment, delivery mode selection, labor process observation and shoulder dystocia management, and the causal relationship between them and the damage consequences of the children were summarized. RESULTS: Fault medical behavior was assessed as the primary cause in 2 cases, equal cause in 10 cases, secondary cause in 8 cases, minor cause in 1 case, no causal relationship in 1 case, and unclear causal force in 3 cases. CONCLUSIONS: In the process of forensic identification of OBPP, whether medical behaviors fulfill diagnosis and treatment obligations should be objectively analyzed from the aspects of prenatal evaluation, delivery mode notification, standardized use of oxytocin, standard operation of shoulder dystocia, etc. Meanwhile, it is necessary to fully consider the objective risk of different risk factors and the difficulty of injury prevention, and comprehensively evaluate the causal force of fault medical behavior in the damage consequences.


Assuntos
Neuropatias do Plexo Braquial , Plexo Braquial , Paralisia Obstétrica , Distocia do Ombro , Gravidez , Feminino , Criança , Humanos , Estudos Retrospectivos , Paralisia Obstétrica/etiologia , Neuropatias do Plexo Braquial/etiologia , Neuropatias do Plexo Braquial/complicações , Fatores de Risco , Paralisia/complicações
15.
ACS Sens ; 9(3): 1555-1564, 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38442411

RESUMO

Extracellular vesicle microRNAs (EV miRNAs) are critical noninvasive biomarkers for early cancer diagnosis. However, accurate cancer diagnosis based on bulk analysis is hindered by the heterogeneity among EVs. Herein, we report an approach for profiling single-EV multi-miRNA signatures by combining total internal reflection fluorescence (TIRF) imaging with a deep learning (DL) algorithm for the first time. This innovative technique allows for the precise characterization of EV miRNAs at the single-vesicle level, overcoming the challenges posed by EV heterogeneity. TIRF with high resolution and a signal-to-noise ratio can simultaneously detect multi-miRNAs in situ in individual EVs. DL algorithm avoids complicated and inaccurate artificial feature extraction, achieving automated high-resolution image analysis. Using this approach, we reveal that the main variation of EVs from 5 cancer cells and normal plasma is the triple-positive EV subpopulation, and the classification accuracy of single triple-positive EVs from 6 sources can reach above 95%. In the clinical cohort, 20 patients (5 lung cancer, 5 breast cancer, 5 cervical cancer, and 5 colon cancer) and 5 healthy controls are predicted with an overall accuracy of 100%. This single-EV strategy provides new opportunities for exploring more specific EV biomarkers to achieve cancer diagnosis and classification.


Assuntos
Neoplasias da Mama , Aprendizado Profundo , Vesículas Extracelulares , MicroRNAs , Humanos , Feminino , MicroRNAs/genética , Biomarcadores
16.
Heliyon ; 10(6): e27748, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38533023

RESUMO

Self-oscillating systems can directly convert ambient energy to mechanical work, and new type self-oscillating systems are worth designing for applications in energy harvesters, engines, and actuators. Taking inspiration from the hand drill, we have developed a novel self-rotating drill system, which is consist of a turnplate and a liquid crystal elastomer (LCE) fiber under steady illumination. To investigate the self-rotating behaviors of the LCE drill, we have proposed a nonlinear theoretical model of the LCE drill under steady illumination based on the well-established dynamic LCE model. Numerical calculation reveals that the LCE drill can undergo a supercritical Hopf bifurcation between the static regime and the self-rotation regime. The self-rotation of drill originates from the contraction of winding portion of LCE fiber in illumination at winding state, and its continuous periodic motion is sustained by the interrelation between light energy and damping dissipation. The Hopf bifurcation conditions are also investigated in detail, as well as the vital system parameters affecting its frequency and amplitude. In contrast to the abundant existing self-oscillating systems, this self-rotating drill stands out due to its simple and lightweight structure, customizable dimensions, and high speed, and thus facilitates the design of compact and integrated systems, enhancing their applicability in microdevices and systems. This bears great significance in fields like micro-robotics, micro-sensors, and medical instruments, enabling the realization of smaller and higher-performance devices.

17.
Proc Natl Acad Sci U S A ; 121(12): e2316230121, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38483987

RESUMO

Mutations in the PKD2 gene, which encodes the polycystin-2 (PC2, also called TRPP2) protein, lead to autosomal dominant polycystic kidney disease (ADPKD). As a member of the transient receptor potential (TRP) channel superfamily, PC2 functions as a non-selective cation channel. The activation and regulation of the PC2 channel are largely unknown, and direct binding of small-molecule ligands to this channel has not been reported. In this work, we found that most known small-molecule agonists of the mucolipin TRP (TRPML) channels inhibit the activity of the PC2_F604P, a gain-of-function mutant of the PC2 channel. However, two of them, ML-SA1 and SF-51, have dual regulatory effects, with low concentration further activating PC2_F604P, and high concentration leading to inactivation of the channel. With two cryo-electron microscopy (cryo-EM) structures, a molecular docking model, and mutagenesis results, we identified two distinct binding sites of ML-SA1 in PC2_F604P that are responsible for activation and inactivation, respectively. These results provide structural and functional insights into how ligands regulate PC2 channel function through unusual mechanisms and may help design compounds that are more efficient and specific in regulating the PC2 channel and potentially also for ADPKD treatment.


Assuntos
Rim Policístico Autossômico Dominante , Canais de Cátion TRPP , Humanos , Canais de Cátion TRPP/metabolismo , Rim Policístico Autossômico Dominante/tratamento farmacológico , Rim Policístico Autossômico Dominante/genética , Rim Policístico Autossômico Dominante/metabolismo , Microscopia Crioeletrônica , Simulação de Acoplamento Molecular , Canais Iônicos
18.
World J Gastrointest Surg ; 16(2): 438-450, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38463372

RESUMO

BACKGROUND: The neutrophil-to-lymphocyte ratio (NLR), a composite inflammatory biomarker, is associated with the prognosis in patients with colorectal tumors. However, whether the NLR can be used as a predictor of symptomatic postoperative anastomotic leakage (AL) in elderly patients with colon cancer is unclear. AIM: To assess the role of the NLR in predicting the occurrence of symptomatic AL after surgery in elderly patients with colon cancer. METHODS: Data from elderly colon cancer patients who underwent elective radical colectomy with anastomosis at three centers between 2018 and 2022 were retrospectively analyzed. Receiver operating characteristic curve analysis was performed to determine the best predictive cutoff value for the NLR. Twenty-two covariates were matched using a 1:1 propensity score matching method, and univariate and multivariate logistic regression analyses were used to determine risk factors for the development of postoperative AL. RESULTS: Of the 577 patients included, 36 (6.2%) had symptomatic AL. The optimal cutoff value of the NLR for predicting AL was 2.66. After propensity score matching, the incidence of AL was significantly greater in the ≥ 2.66 NLR subgroup than in the < 2.66 NLR subgroup (11.5% vs 2.5%; P = 0.012). Univariate logistic regression analysis revealed statistically significant correlations between blood transfusion intraoperatively and within 2 d postoperatively, preoperative albumin concentration, preoperative prognostic nutritional index, and preoperative NLR and AL occurrence (P < 0.05); multivariate logistic regression analysis revealed that an NLR ≥ 2.66 [odds ratio (OR) = 5.51; 95% confidence interval (CI): 1.50-20.26; P = 0.010] and blood transfusion intraoperatively and within 2 d postoperatively (OR = 2.52; 95%CI: 0.88-7.25; P = 0.049) were risk factors for the occurrence of symptomatic AL. CONCLUSION: A preoperative NLR ≥ 2.66 and blood transfusion intraoperatively and within 2 d postoperatively are associated with a higher incidence of postoperative symptomatic AL in elderly patients with colon cancer. The preoperative NLR has predictive value for postoperative symptomatic AL after elective surgery in elderly patients with colon cancer.

19.
Eur Respir J ; 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38514095

RESUMO

INTRODUCTION: Patients with allergic bronchopulmonary aspergillosis (ABPA) suffer from repeated exacerbations. However, the involvement of T cell subsets remains unclear. METHODS: We enrolled ABPA patients, asthma patients and healthy controls. Th1, Th2, Th17, Treg and IL-21+CD4+T cells in total or sorted subsets of peripheral blood mononuclear cells (PBMCs) and ABPA Bronchoalveolar Lavage fluid (BALF) were analyzed by flow cytometry. RNA sequencing of subsets of CD4+T cells were done in exacerbated ABPA patients and healthy controls. Antibodies of T-B cell co-cultures in vitro were measured. RESULTS: ABPA patients had increased Th2 cells, similar Treg cells and decreased circulating Th1 and Th17 cells. IL-5+IL-13+IL-21+CD4+T cells was rarely detected in healthy controls but significantly elevated in the blood of ABPA patients, especially the exacerbated ones. We found that IL-5+IL-13+IL-21+CD4+T cells were mainly peripheral T helper (Tph) cells (PD-1+CXCR5-), which also presented in the BALF of ABPA patients. The proportions of circulating Tph were similar among ABPA patients, asthma patients and healthy controls, while IL-5+IL-13+IL-21+ Tph cells significantly increased in ABPA patients. Transcriptome data showed that Tph cells of ABPA patients were Th2-skewed and exhibited signatures of follicular T helper (Tfh) cells. When co-cultured in vitro, Tph cells of ABPA patients induced the differentiation of autologous B cells into plasmablasts and significantly enhanced the production of IgE. CONCLUSION: We identified a distinctly elevated population of circulating Th2-skewed Tph cells that induced the production of IgE in ABPA patients. It may be a biomarker and therapeutic target for ABPA.

20.
Clin Nucl Med ; 49(5): 409-418, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38465929

RESUMO

PURPOSE: In this study, we evaluated and compared the diagnostic performances of 68 Ga-FAPI-04 PET/CT and 18 F-FDG PET/CT for primary and metastatic cholangiocarcinoma (CCA) lesions. We also investigated the performance of PET/MR for visualizing and characterizing CCA and liver metastasis lesions. PATIENTS AND METHODS: Forty-four patients with suspected CCA were recruited and underwent 68 Ga-FAPI-04 and 18 F-FDG PET/CT within 1 week, including 30 patients who underwent simultaneous abdominal 68 Ga-FAPI-04 PET/MR scanning. The findings were confirmed by histopathology or radiographic follow-up. RESULTS: Compared with 18 F-FDG PET/CT, 68 Ga-FAPI-04 PET/CT showed higher sensitivity (94.3% vs 88.6%) and the same accuracy (86.4% vs 86.4%) in evaluating primary tumors. However, its specificity was lower (55.6% vs 77.8%). 68 Ga-FAPI-04 PET was superior to 18 F-FDG PET in both patient-based and lesion-based evaluations except for metastatic lesions in the liver and bone. For intrahepatic CCA, 68 Ga-FAPI-04 PET/CT and 18 F-FDG PET/CT (100% vs 100%) had similar detection rates, with similar uptake levels between tracers ( P > 0.05). However, for extrahepatic CCA, 68 Ga-FAPI-04 PET/CT had a higher detection rate (89.5% vs 78.9%), and 68 Ga-FAPI-04 had a higher uptake ( P < 0.05). PET/MR was more effective than PET/CT in terms of lesion conspicuity and diagnostic confidence for primary tumors and liver metastases. In addition, multisequence MRI identified more liver metastases than 68 Ga-FAPI-04 PET/CT and 18 F-FDG PET/CT. CONCLUSIONS: Compared with 18 F-FDG PET/CT, 68 Ga-FAPI-04 PET/CT showed a higher sensitivity in detecting primary CCA tumors, involved lymph nodes, and peritoneal metastases. Compared with 68 Ga-FAPI-04 PET/CT, PET/MR detected primary and liver metastatic lesions more accurately. For extrahepatic CCA, the combination of 68 Ga-FAPI-04 PET/CT and abdominal PET/MRI may replace 18 F-FDG PET/CT.


Assuntos
Neoplasias dos Ductos Biliares , Colangiocarcinoma , Neoplasias Hepáticas , Quinolinas , Humanos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Fluordesoxiglucose F18 , Peritônio , Colangiocarcinoma/diagnóstico por imagem , Radioisótopos de Gálio , Imageamento por Ressonância Magnética , Neoplasias dos Ductos Biliares/diagnóstico por imagem , Ductos Biliares Intra-Hepáticos
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