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1.
J Environ Manage ; 365: 121645, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38959768

RESUMO

Priority ecological reserves (PER) aim to protect areas with significant ecological value and crucial ecological functions, optimizing resource allocation to maximize the benefits of ecological conservation. However, most previous studies have considered only ecosystem services (ESs) in delineating PER, neglecting eco-environmental quality (EEQ). This study used the Remote Sensing-based Ecological Index (RSEI) to represent EEQ and combined it with ESs to delineate PER at the county scale in the Yellow River Basin (YRB). Additionally, it employed Multiscale Geographically Weighted Regression to identify the driving factors influencing the ESs and EEQ of PER. The results showed that: (1) From 2000 to 2020, both RSEI and the Comprehensive ESs (CES) in the YRB exhibited a fluctuating upward trend; (2) Three types of PER were extracted, with ESs reserve mainly distributed in the upstream region, EEQ reserve primarily in the middle and lower reaches, and integrated ecological reserve mainly in the midstream region, all dominated by vegetation land-use types; (3) Within the extracted PER, RSEI was mainly influenced by soil, aspect, population (pop), PM2.5, temperature (tmp), and potential evapotranspiration (pet), while CES was affected by soil, pop, PM2.5, slope, tmp, precipitation, and pet. To enhance the EEQ and ESs of the YRB, it was recommended to incorporate at least 105,379 km2 into the existing protected areas in the YRB. These areas should be subdivided based on their ecological status, with specific management measures for different types of PER. This study provides recommendations for environmental protection and land planning in the YRB, actively responding to current policies on high-quality development and ecological environmental protection in the YRB.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Rios , Monitoramento Ambiental , Ecologia , China
2.
Entropy (Basel) ; 26(6)2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38920525

RESUMO

In the complex dynamics of modern information systems such as e-commerce and streaming services, managing uncertainty and leveraging information theory are crucial in enhancing session-aware recommender systems (SARSs). This paper presents an innovative approach to SARSs that combines static long-term and dynamic short-term preferences within a counterfactual causal framework. Our method addresses the shortcomings of current prediction models that tend to capture spurious correlations, leading to biased recommendations. By incorporating a counterfactual viewpoint, we aim to elucidate the causal influences of static long-term preferences on next-item selections and enhance the overall robustness of predictive models. We introduce a dual-tower architecture with a novel data augmentation process and a self-supervised training strategy, tailored to tackle inherent biases and unreliable correlations. Extensive experiments demonstrate the effectiveness of our approach, outperforming existing benchmarks and paving the way for more accurate and reliable session-based recommendations.

3.
Chem Biodivers ; : e202400782, 2024 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-38923279

RESUMO

Mesenchymal-epithelial transition factor (c-Met) is a tyrosine kinase receptor. Under certain disease conditions, the cellular transformation process may be over-activated, resulting in carcinogenesis. Therefore, molecularly targeted therapy targeting the receptor tyrosine kinase c-Met is achieved by inhibiting c-Met activity and thus effectively suppressing cancer propagation. In this paper, 41 compounds were selected from the reported literature as a dataset to build stable Topomer CoMFA and HQSAR models. The feasibility of the constructed models was evaluated by internal and external validation techniques. Based on the Topomer CoMFA model basis the fragments with higher contribution values were screened and the combination yielded 19 compounds with higher than template molecules. Through molecular docking, the ligand complexes formed hydrogen and hydrophobic bonds with strong stable structures. The ligand-protein complexes with better scoring results were selected for MD simulations, and Y14 exhibited a stable and favourable binding pocket. In addition, ADMET results showed that the ligand-complexes have potential medicinal effects on c-Met inhibition. This study provides a reference for molecularly targeted therapy targeting receptor tyrosine-kinetic c-Met.

4.
World J Clin Cases ; 12(6): 1111-1119, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38464918

RESUMO

BACKGROUND: Neuroendocrine neoplasms of the female genital tract are rare. AIM: To enhance our clinical understanding of neuroendocrine carcinoma (NEC) of the ovary. METHODS: A retrospective review was conducted on 12 patients diagnosed with NEC of the ovary, analyzing clinicopathological characteristics, treatment modalities, and survival status. RESULTS: The median age at diagnosis was 34.5 years (range: 20 to 62 years). Among the 12 cases, 9 were small cell carcinoma of the ovary and 3 were large cell NEC. Five cases were stage I tumors, one case was stage IV, and six cases were stage III. Eleven patients underwent surgery as part of their treatment. All patients received adjuvant chemotherapy. Among the 12 patients, one patient received radiotherapy, and one patient with a BRCA2 mutation was administered PARP inhibitor maintenance after chemotherapy. The median progression-free survival was 13 months, and the median overall survival was 19.5 months. Four cases remained disease-free, while eight cases experienced tumor recurrence, including three cases that resulted in death due to disease recurrence. CONCLUSION: NEC of the ovary is a rare condition that is more common in women of childbearing age and is associated with aggressive behavior and poor clinical outcomes. Surgical resection remains the mainstay of treatment, with some patients benefiting from adjuvant chemoradiation therapy.

5.
Insect Biochem Mol Biol ; 168: 104114, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38552809

RESUMO

The Drosophila hindgut is a classical model to study organogenesis. The adult hindgut originates from the precursor cells in the larval hindgut. However, the territory of these cells has still not been well determined. A ring of wingless (wg)-expressing cells lies at the anterior zone of both the larval and adult hindgut. The larval Wg ring was thought as a portion of precursor of the adult hindgut. By applying a cell lineage tracing tool (G-TRACE), we demonstrate that larval wg-expressing cells have no cell lineage contribution to the adult hindgut. Additionally, adult Wg ring cells do not divide and move posteriorly to replenish the hindgut tissue. Instead, we determine that the precursors of the adult pylorus and ileum are situated in the cubitus interruptus (ci)-expressing cells in the anterior zone, and deduce that the precursor stem cells of the adult rectum locate in the trunk region of the larval pylorus including hedgehog (hh)-expressing cells. Together, this research advances our understanding of cell lineage origins and the development of the Drosophila hindgut.


Assuntos
Proteínas de Drosophila , Drosophila , Animais , Drosophila/metabolismo , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Larva/genética , Larva/metabolismo , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/metabolismo , Proteína Wnt1 , Proteínas Hedgehog/genética , Regulação da Expressão Gênica no Desenvolvimento
6.
J Environ Manage ; 354: 120415, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38417359

RESUMO

Aboveground biomass (AGB) in grasslands directly reflects the net primary productivity, making it a sensitive indicator of grassland resource quality and ecological degradation. Accurately estimating AGB over large regions to reveal long-term AGB evolution trends remains a formidable challenge. In this study, we divided Inner Mongolia Autonomous Region (IMAR) grasslands into three study regions based on their spatial distribution of grassland types. We combined remote sensing data with ground-based sample data collected over the past 19 years from 6114 field plots using the Google Earth Engine platform. We constructed random forest (RF) and traditional regression AGB inversion models for each region and selected the best-performing model through accuracy assessment to estimate IMAR grassland AGB for the period 2000-2022. We also examined the trends in AGB changes and identified the driving forces affecting IMAR grasslands through the application of Theil-Sen estimation, Mann-Kendall trend analysis, and the Geodetector model. The main findings are as follows: (1) Compared with the univariate parametric traditional regression model, the AGB monitoring accuracy of the multivariate non-parametric RF model in the three study regions increased by 5.94%, 5.08% and 19.14%, respectively. (2) The average AGB per unit area of IMAR grasslands from 2000 to 2022 was 731.41 kg/hm2, with alpine meadow having the highest average AGB (1271.70 kg/hm2) and temperate grassland desertification having the lowest (469.06 kg/hm2). IMAR grasslands exhibited an overall increasing trend in AGB over the past 23 years (6.01 kg/hm2•yr), with the increasing trend covering 83.52% of the grassland area and the decreasing trend covering 16.48%. (3) Spatially, IMAR grassland AGB showed a gradual decline from northeast to southwest and exhibited an increasing trend with increasing longitude (45.423 kg/hm2 per degree) and latitude (71.9 kg/hm2 per degree). (4) Meteorological factors were the most significant factors affecting IMAR grassland AGB, with precipitation (five-year average q value of 0.61) being the most prominent. In the western part of IMAR, where precipitation is consistently limited throughout the year, the primary drivers of influence were human activities, with particular emphasis on the number of livestock (with a five-year average q value of 0.44). It is evident that reducing human activity disturbance and pressure in fragile grassland areas or implementing near-natural restoration measures will be beneficial for the sustainable development of grassland ecosystems. The results of this research hold substantial reference importance for the protection and restoration of grasslands, the supervision and administration of grassland resources, as well as the development of policies related to grassland management.


Assuntos
Ecossistema , Pradaria , Animais , Humanos , Biomassa , China , Gado
7.
J Ovarian Res ; 17(1): 4, 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-38178252

RESUMO

OBJECTIVE: Investigating the utility of serum exosomal markers CA125, HE4, and C5a, both individually and in combination, for distinguishing between benign and malignant ovarian tumors. METHODS: In this study, we selected a total of 234 patients diagnosed with ovarian tumors, including 34 with malignant tumors, 10 with borderline ovarian tumors, and 190 with benign tumors. This study conducted comparisons of exosomal levels of CA125, HE4, and C5a among distinct groups, as well as making comparisons between serum and exosomal levels of CA125 and HE4. Furthermore, the diagnostic performance was assessed through Receiver Operating Characteristic (ROC) curve analysis. The Area Under the Curve (AUC) was computed, and a comparative evaluation of sensitivity and specificity was conducted to ascertain their effectiveness in determining the nature of ovarian tumors across different markers. RESULTS: Serum CA125 and HE4 levels, the ROMA index, exosomal CA125, HE4, C5a levels, and their combined applied value (OCS value) were notably elevated in the ovarian non-benign tumor group compared to the benign tumor group, with statistical significance (P < 0.05). Exosomal and serum levels of CA125 and HE4 exhibited a positive correlation, with concentrations of these markers in serum surpassing those in exosomes. The combined OCS (AUC = 0.871) for CA125, HE4, and C5a in exosomes demonstrated superior sensitivity (0.773) and specificity (0.932) compared to serum tumor markers (CA125, HE4) and the ROMA index. The tumor stage represents an autonomous risk factor influencing the prognosis of individuals with ovarian malignancies. CONCLUSION: The stage of ovarian malignancy is an independent risk factor for its prognosis. The combination of exosomal CA125, HE4 and C5a has a higher clinical value for the identification of the nature of ovarian tumours.


Assuntos
Neoplasias Ovarianas , Proteínas , Feminino , Humanos , Proteínas/análise , Diagnóstico Diferencial , Neoplasias Ovarianas/patologia , Sensibilidade e Especificidade , Biomarcadores Tumorais , Curva ROC , Antígeno Ca-125 , Algoritmos
8.
Comput Struct Biotechnol J ; 23: 700-710, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38292475

RESUMO

Introduction: The disconnected-interacting protein 2 homolog A (DIP2A), a member of disconnected-interacting 2 protein family, has been shown to be involved in human nervous system-related mental illness. This protein is highly expressed in the nervous system of mouse. Mutation of mouse DIP2A causes defects in spine morphology and synaptic transmission, autism-like behaviors, and defective social novelty [5], [27], indicating that DIP2A is critical to the maintenance of neural development. However, the role of DIP2A in neural differentiation has yet to be investigated. Objective: To determine the role of DIP2A in neural differentiation, a neural differentiation model was established using mouse embryonic stem cells (mESCs) and studied by using gene-knockout technology and RNA-sequencing-based transcriptome analysis. Results: We found that DIP2A is not required for mESCs pluripotency maintenance, but loss of DIP2A causes the neural differentiation abnormalities in both N2B27 and KSR medium. Functional knockout of Dip2a gene also decreased proliferation of mESCs by perturbation of the cell cycle and profoundly inhibited the expression of a large number of neural development-associated genes which mainly enriched in spinal cord development and postsynapse assembly. Conclusions: The results of this report demonstrate that DIP2A plays an essential role in regulating differentiation of mESCs towards the neural fate.

9.
PLoS One ; 18(10): e0292901, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37856494

RESUMO

This study focuses on effectively controlling landslides at the boundary of a soft rock open-pit dump while ensuring safe increases in the dump's capacity and optimal utilization of external dump sites. To achieve this, the adoption of a local filling method for the dump base is proposed. By leveraging the concepts of limit equilibrium theory and equivalent shear strength parameters, the mathematical expression of the slope stability coefficient in the Morgenstern-Price method is derived and improved. This improved method is then applied to a real engineering example to determine the optimal basement replacement rate required to maintain slope stability. The findings reveal that the local filling of the base is well-suited for slopes susceptible to potential landslides associated with cutting layers, bedding layers, and swelling. For practical ease, it is advisable to choose the lowest step in the dump's slope for construction convenience. As the local replacement rate of the base increases, the slope's stability coefficient gradually improves, with the K-Fs ratio showing a prominent role in this process. Additionally, numerical simulation methods are employed to elucidate the mechanism of the dump's landslide following local basement replacement, thereby providing comprehensive evidence of the engineering applicability of this method. The research results demonstrate a promising practical application prospect for effectively controlling the stability of soft base dump slopes.

10.
Stem Cell Res Ther ; 14(1): 248, 2023 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-37705068

RESUMO

BACKGROUND: Disco-interacting protein 2 homolog B is a member of the Dip2 family encoded by the Dip2b gene. Dip2b is widely expressed in neuro-related tissues and is essential in axonal outgrowth during embryogenesis. METHODS: Dip2b knockout mouse embryonic stem cell line was established by CRISPR/Cas9 gene-editing technology. The commercial kits were utilized to detect cell cycle and growth rate. Flow cytometry, qRT-PCR, immunofluorescence, and RNA-seq were employed for phenotype and molecular mechanism assessment. RESULTS: Our results suggested that Dip2b is dispensable for the pluripotency maintenance of mESCs. Dip2b knockout could not alter the cell cycle and proliferation of mECSs, or the ability to differentiate into three germ layers in vitro. Furthermore, genes associated with axon guidance, channel activity, and synaptic membrane were significantly downregulated during neural differentiation upon Dip2b knockout. CONCLUSIONS: Our results suggest that Dip2b plays an important role in neural differentiation, which will provide a valuable model for studying the exact mechanisms of Dip2b during neural differentiation.


Assuntos
Células-Tronco Embrionárias Murinas , Crescimento Neuronal , Animais , Camundongos , Ciclo Celular , Divisão Celular , Linhagem Celular , Camundongos Knockout
11.
Int J Biometeorol ; 67(6): 1017-1030, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37072578

RESUMO

Climate warming may induce growth decline in warm-temperate areas subjected to seasonal soil moisture deficit, whereas increasing atmospheric CO2 concentration (Ca) is expected to enhance tree growth. An accurate understanding of tree growth and physiological processes responding to climate warming and increasing Ca is critical. Here, we analyzed tree-ring stable carbon isotope and wood anatomical traits of Pinus tabuliformis from Qinling Mountains in China to understand how lumen diameter (LD) determining potential hydraulic conductivity and cell-wall thickness (CWT) determining carbon storage responded to climate and Ca. The effects of climate and Ca on intrinsic water-use efficiency (iWUE) were isolated, and iWUE values due to only-climate (iWUEClim) and only-CO2 effects (iWUECO2) were obtained. During a low-iWUE period, the influences of climate on earlywood (EW) LD and latewood (LW) CWT prevailed. During a high-iWUE period, CO2 fertilization promoted cell enlargement and carbon storage but this was counteracted by a negative influence of climate warming. The limiting direct effects of iWUEClim and indirect effects of climate on EW LD were greater than on LW CWT. P. tabuliformis in temperate forests will face a decline of growth and carbon fixation, but will produce embolism-resistant tracheids with narrow lumen responding to future hotter droughts.


Assuntos
Água , Madeira , Dióxido de Carbono , Clima , Árvores , Florestas , Carbono , Secas
12.
Sensors (Basel) ; 23(3)2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36772264

RESUMO

We construct a spacecraft performance-fault relationship graph of the control system, which can help space robots locate and repair spacecraft faults quickly. In order to improve the performance-fault relationship graph, we improve the Deep Deterministic Policy Gradient (DDPG) algorithm, and propose a relationship prediction method that combines representation learning reasoning with deep reinforcement learning reasoning. We take the spacecraft performance-fault relationship graph as the agent learning environment and adopt reinforcement learning to realize the optimal interaction between the agent and the environment. Meanwhile, our model uses a deep neural network to construct a complex value function and strategy function, which makes the agent have excellent perceptual decision-making ability and accurate value judgment ability. We evaluate our model on a performance-fault relationship graph of the control system. The experimental results show that our model has high prediction speed and accuracy, which can completely infer the optimal relationship path between entities to complete the spacecraft performance-fault relationship graph.

13.
BMC Surg ; 22(1): 334, 2022 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-36085145

RESUMO

BACKGROUND: Laparoscopic-assisted repairs for pediatric inguinal hernia have gained gradual acceptance over the past decade. However, consensus about the optimal management is still lacking. The aim of this study is to compare outcomes of a modified laparoscope-assisted single-needle laparoscopic percutaneous extraperitoneal closure (LPEC) versus open repair of pediatric hernias/hydrocele in a single institution. MATERIALS AND METHODS: We retrospectively reviewed the medical data of children who underwent laparoscope-assisted single-needle LPEC and open repair (OR) for inguinal hernia from 2014 to 2019. Data collection included demographics, laterality of hernia, surgical time and time to follow-up. We also reviewed and analyzed the evidence of recurrence, the incidence of metachronous contralateral inguinal hernia (MCIH), and other complications. RESULTS: In our cohort, 961 patients in the OR group and 1098 patients in the LPEC group were analyzed retrospectively. Mean operative time was significantly shorter in the LPEC group (22.3 ± 3.5 min) than in the OR group (27.8 ± 5.9 min) for bilateral hernia repair (p < 0.001). Postoperative recurrence was 1.3% (13/1035) in the OR group and 0.5% (6/1182) in the LPEC group (p = 0.056). Iatrogenic cryptorchidism occurred statistically more frequently in the OR group than in the LPEC group (0.4% vs. 0%, p = 0.013). In addition, the incidence of MCIH was 3.7% (33/887) in the OR group and 0.3% (3/1014) in the LPEC group (p < 0.01). CONCLUSION: Comparing to open technique, laparoscope-assisted single-needle LPEC provides a simple and effective option for pediatric inguinal hernia/hydrocele repair with excellent outcomes, a low incidence of recurrence, and reduced MCIH.


Assuntos
Hérnia Inguinal , Laparoscopia , Hidrocele Testicular , Criança , Hérnia Inguinal/cirurgia , Humanos , Laparoscópios , Masculino , Agulhas , Estudos Retrospectivos
14.
J Environ Manage ; 317: 115351, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35642818

RESUMO

Changes in land use and landscapes have a direct impact on the regional eco-environment. It is of great importance to understand the change pattern of land use, landscapes, and their mechanism on the ecological quality, especially ecologically fragile areas. The northern sand-prevention belt (NSPB) is an important ecologically fragile area in China, which has a large influence on the ecological security of the entire country. Based on the land use data of the NSPB in 2000, 2010, and 2018, we studied the spatio-temporal characteristics of land-use change and change in landscape patterns. The ecological quality represented by the remote sensing-based desertification index (RSDI) was calculated using satellite images. The effects of land use and landscape patterns on RSDI were analyzed by geographic detector and geographically weighted regression. Important results include the following: (1) Land-use change in the study area was high during 2000-2010 but slower in 2010-2018. Grassland was the largest land-use type in the NSPB, and varied greatly in terms of total change and spatial location. The major change was the conversion between dense and moderate grass, with 64,860 km2 of dense grass turning into moderate grass, and 48,505 km2 changing the other way. (2) Among the four landscape metrics, patch density, area-weighted mean fractal dimension, and edge density increased, whereas the aggregation index decreased, which indicated that the landscape was developing towards heterogeneity, fragmentation, complexity, and aggregation. Spatially, the landscape metrics presented a strip distribution in the east of the NSPB. (3) The effects of various land-use types on ecological quality, from high to low, were unused land, woodland, dense grass, cropland, moderate grass, built-up land, sparse grass, and waterbody. The areas where the ecological quality was greatly affected by the landscape patterns were concentrated in the agro-pastoral ecotone and the forest-steppe ecotone. The results of this study reveal the trends of land use and landscape patterns in the NSPB over 18 years and can help to understand their mechanism on ecological quality, which is of significance for the management of this area.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , China , Florestas , Poaceae , Areia
15.
Int J Urol ; 29(3): 235-241, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34872161

RESUMO

OBJECTIVE: To explore the efficacy of quantitative renal volume measures on magnetic resonance urography images in predicting need for surgery among children with ureteropelvic junction obstruction and their ability to evaluate renal function. METHODS: A total of 88 cases of hydronephrosis in 50 patients were collected between 1 April 2018 and 31 March 2020, including 30 operated kidney and 58 unoperated kidney cases. Clinical data were collected, and quantitative analysis of magnetic resonance urography was performed. Renal volume, hydronephrosis volume and the volume ratio of hydronephrosis (hydronephrosis volume/renal volume) were measured and calculated. We analyzed the relationships between the above indices in the two groups and compared these with renal function. RESULTS: Compared with the unoperated kidney group, hydronephrosis volume, renal volume and hydronephrosis volume/renal volume of the operated kidney group increased significantly. Hydronephrosis volume (area under the curve 0.972, 95% confidence interval 0.943-1.000; P < 0.001) and hydronephrosis volume/renal volume (area under the curve 0.968, 95% confidence interval 0.939-0.998; P < 0.001) were superior to ultrasonography and renal function examination in predicting the probability of surgery, and their sensitivity values (hydronephrosis volume/renal volume: 96.67%; hydronephrosis volume: 93.33%) were higher than those of the renal function test (50%). There was a significant difference among different renal function groups in the pairwise comparison of hydronephrosis volume and hydronephrosis volume/renal volume (P < 0.05). CONCLUSION: Quantitative volume measures of hydronephrosis by magnetic resonance urography had a greater ability to predict need for surgery than ultrasonography and dynamic renal imaging, and it can be used as method by which to evaluate surgery. Hydronephrosis volume and hydronephrosis volume/renal volume have greater predictive ability, and play an important role in the deterioration of renal function.


Assuntos
Hidronefrose , Obstrução Ureteral , Criança , Humanos , Hidronefrose/diagnóstico por imagem , Hidronefrose/etiologia , Hidronefrose/cirurgia , Lactente , Rim/diagnóstico por imagem , Rim/fisiologia , Rim/cirurgia , Pelve Renal/cirurgia , Estudos Retrospectivos , Obstrução Ureteral/diagnóstico por imagem , Obstrução Ureteral/cirurgia
16.
Microb Drug Resist ; 28(2): 229-235, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34851749

RESUMO

Purpose: With the emergence of multidrug-resistant and pan-resistant strains, Klebsiella pneumoniae (K. pneumoniae) shows higher treatment failure rates and mortality in clinics. It is more important to develop an effective method for treating K. pneumonia infections. The main objectives of this study were to determine the minimal inhibitory concentration (MIC) and the mutant prevention concentration (MPC) for eight antimicrobial agents against K. pneumoniae isolated from different hosts and compare the emergence of resistant mutants between animal strains and human strains. Materials and Methods: A total of 72 nonduplicate K. pneumoniae isolates and 8 antimicrobial agents (amikacin, azithromycin, levofloxacin, doxycycline, nitrofurantoin, colistin, tigecycline, and imipenem) were used. The MIC and MPC values were determined using agar plate assays. The values of the selection index (SI) were calculated with MPC90/MIC90. Pharmacodynamic parameters were calculated using published plasma pharmacokinetic variables. Results: For human isolate strains, the MPC50/90 (µg/mL) values were as follows: amikacin, 32/128; azithromycin, 64/128; levofloxacin, 4/16; doxycycline, 32/32; nitrofurantoin, 128/512; colistin, 4/8; tigecycline, 8/16; and imipenem, 4/8. The value of SI was 8 for azithromycin, doxycycline, and tigecycline; 16 for amikacin, levofloxacin, and nitrofurantoin; 4 for imipenem; and 2 for colistin. For animal isolate strains, the MPC90 values were 128 µg/mL for azithromycin and doxycycline, 64 µg/mL for amikacin, 32 µg/mL for levofloxacin, 512 µg/mL for nitrofurantoin, 8 µg/mL for colistin and tigecycline, 4 µg/mL for imipenem. The value of SI was 2 for colistin and imipenem, 8 for tigecycline, 16 for amikacin, and 32 for the other four agents. In combination with pharmacokinetic parameters, these findings indicated that the plasma concentrations of the seven antibiotics except imipenem were below the MPC for the entire dosing interval. Conclusion: The ability of eight antibiotics to prevent resistant mutants of K. pneumoniae was different between animal strains and human strains. Higher doses than those currently approved should be required to prevent the enrichment of mutants of drug-resistant bacteria in the clinics.


Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana Múltipla , Klebsiella pneumoniae/efeitos dos fármacos , Animais , Antibacterianos/farmacocinética , Área Sob a Curva , Relação Dose-Resposta a Droga , Meia-Vida , Humanos , Taxa de Depuração Metabólica , Testes de Sensibilidade Microbiana
18.
Stem Cell Res ; 53: 102236, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33813174

RESUMO

DIP2 protein contains three members: DIP2A, DIP2B and DIP2C, and are broadly expressed in the nervous system from Drosophila to human during embryonic development. Dip2c gene-associated mutations have been reported in tumors and neuronal diseases. However, the role ofDip2cin the context of mouse embryonic stem (mES) cells has not been explored.To investigate the biological function of Dip2c during early embryo development, we generated Dip2c-/- mES line using a CRISPR/Cas9 system. This cell line has contributed to further investigation of molecular mechanism of Dip2c during cell differentiation, as well as a cell model for screening for neurogenic drug and cancer clinical cure.


Assuntos
Sistemas CRISPR-Cas , Edição de Genes , Animais , Sistemas CRISPR-Cas/genética , Linhagem Celular , Feminino , Camundongos , Camundongos Knockout , Gravidez , Tecnologia
19.
Peptides ; 136: 170469, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33309723

RESUMO

Neuropeptide FF (NPFF) is a neuropeptide that modulates various physiological processes. The regulatory role of NPFF in the immune and inflammatory response is currently being revealed. However, the effect of NPFF at the transcriptome level in macrophages has not been fully elucidated. Here, the impact of NPFF on gene expression at the transcriptome level of RAW 264.7 cells was investigated by RNA-seq. RAW 264.7 macrophages were treated with NPFF (1 nM) for 18 h, followed by RNA-seq examination. Differentially expressed genes (DEGs) were acquired, followed by GO, KEGG, and PPI analysis. A total of eight qPCR-verified DEGs were obtained. Next, three-dimensional models of the eight hub proteins were constructed by using homology modeling with Modeller (9v23). Finally, molecular dynamics simulation (300 ns) was performed with GROMACS 2018.2 to investigate the structural characteristics of these hub proteins. NPFF had no detectable effect on the morphology of RAW264.7 cells. A total of 211 DEGs were acquired, and an enrichment study demonstrated that the immune response-related pathway was significantly inhibited by NPFF. Moreover, the molecular dynamics optimized-protein models of the hub proteins were obtained. Collectively, NPFF inhibited the expression of immune-related genes in RAW 264.7 cells at the transcriptome level, which suggested a negative relationship between NPFF and this set of immune-related genes in RAW 264.7 macrophages. Therefore, our data may provide direct evidence of the role of NPFF in peripheral or central inflammatory diseases.


Assuntos
Inflamação/tratamento farmacológico , Oligopeptídeos/genética , Transcriptoma/efeitos dos fármacos , Animais , Linhagem Celular , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Inflamação/genética , Inflamação/patologia , Macrófagos/efeitos dos fármacos , Camundongos , Oligopeptídeos/farmacologia , Células RAW 264.7 , Receptores de Neuropeptídeos/genética
20.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-875972

RESUMO

Objective@#To study the computational fluid dynamics (CFD) characteristics of ultrasonic root canal irrigation when the file was placed at a certain depth in the root canal, to provide a reference for clinical application.@*Methods @#First, scanning laser vibrometry (SLV) was utilized to analyze the characteristics of vibrational ultrasonic files under specific power. Then ICEM CFD 18.0 software was used to establish the root canal ultrasonic irrigation model. The insertion position of the ultrasonic working tip was set 1 mm away from the physiological apical foramen, and cloud images of the results were obtained by FLUENT 18.0 software. Volume fraction, flow velocity and pressure in the root canal were evaluated after setting the computing conditions.@*Results@#The vibration of the ultrasonic working tip was mainly transverse vibration with slight longitudinal vibration. The amplitude of transverse vibration of each part of the working tip was different. Maximum values were observed at the apical end area of the file, and the closer to the base of the file, the smaller the amplitude. The area where the cavitation volume fraction of the rinsing fluid was greater than 0 was concentrated around the working point. The flow rate of the irrigating fluid was up to 2 m/s, within the area 0.2 mm in front of the working tip, the velocity of the irrigating fluid was greater than 0.1 m/s, while within the area 0.8 mm from the root tip, the velocity of the irrigating fluid was small or even zero. The apical pressure value was non-positive when the tip of the file was 1 mm away from the apical foramen in this model.@*Conclusion@# Based on the experimental results, it appears that when the ultrasonic working tip was placed 1 mm short of the working length, the ultrasonic irrigating flow did not overflow the root apical foramen and the irrigation process was relatively safe; the irrigation fluid had a strong irrigation effect within approximately 0.2 mm in front of the working tip.

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