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1.
Molecules ; 29(9)2024 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-38731549

RESUMEN

Targeting translation factor proteins holds promise for developing innovative anti-tuberculosis drugs. During protein translation, many factors cause ribosomes to stall at messenger RNA (mRNA). To maintain protein homeostasis, bacteria have evolved various ribosome rescue mechanisms, including the predominant trans-translation process, to release stalled ribosomes and remove aberrant mRNAs. The rescue systems require the participation of translation elongation factor proteins (EFs) and are essential for bacterial physiology and reproduction. However, they disappear during eukaryotic evolution, which makes the essential proteins and translation elongation factors promising antimicrobial drug targets. Here, we review the structural and molecular mechanisms of the translation elongation factors EF-Tu, EF-Ts, and EF-G, which play essential roles in the normal translation and ribosome rescue mechanisms of Mycobacterium tuberculosis (Mtb). We also briefly describe the structure-based, computer-assisted study of anti-tuberculosis drugs.


Asunto(s)
Proteínas Bacterianas , Mycobacterium tuberculosis , Mycobacterium tuberculosis/metabolismo , Mycobacterium tuberculosis/efectos de los fármacos , Mycobacterium tuberculosis/genética , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/genética , Proteínas Bacterianas/química , Biosíntesis de Proteínas , Factores de Elongación de Péptidos/metabolismo , Factores de Elongación de Péptidos/química , Factores de Elongación de Péptidos/genética , Antituberculosos/farmacología , Antituberculosos/química , Ribosomas/metabolismo , Modelos Moleculares , Tuberculosis/tratamiento farmacológico , Tuberculosis/microbiología , Tuberculosis/metabolismo , Conformación Proteica
2.
Brief Bioinform ; 25(2)2024 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-38493346

RESUMEN

Single-cell assay for transposase-accessible chromatin using sequencing (scATAC-seq) data provided new insights into the understanding of epigenetic heterogeneity and transcriptional regulation. With the increasing abundance of dataset resources, there is an urgent need to extract more useful information through high-quality data analysis methods specifically designed for scATAC-seq. However, analyzing scATAC-seq data poses challenges due to its near binarization, high sparsity and ultra-high dimensionality properties. Here, we proposed a novel network diffusion-based computational method to comprehensively analyze scATAC-seq data, named Single-Cell ATAC-seq Analysis via Network Refinement with Peaks Location Information (SCARP). SCARP formulates the Network Refinement diffusion method under the graph theory framework to aggregate information from different network orders, effectively compensating for missing signals in the scATAC-seq data. By incorporating distance information between adjacent peaks on the genome, SCARP also contributes to depicting the co-accessibility of peaks. These two innovations empower SCARP to obtain lower-dimensional representations for both cells and peaks more effectively. We have demonstrated through sufficient experiments that SCARP facilitated superior analyses of scATAC-seq data. Specifically, SCARP exhibited outstanding cell clustering performance, enabling better elucidation of cell heterogeneity and the discovery of new biologically significant cell subpopulations. Additionally, SCARP was also instrumental in portraying co-accessibility relationships of accessible regions and providing new insight into transcriptional regulation. Consequently, SCARP identified genes that were involved in key Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways related to diseases and predicted reliable cis-regulatory interactions. To sum up, our studies suggested that SCARP is a promising tool to comprehensively analyze the scATAC-seq data.


Asunto(s)
Secuenciación de Inmunoprecipitación de Cromatina , Cromatina , Secuenciación de Inmunoprecipitación de Cromatina/métodos , Cromatina/genética , Genoma , Epigenómica , Análisis de Datos
4.
Appl Opt ; 63(6): 1529-1537, 2024 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-38437365

RESUMEN

Photon counting is an effective way to enhance the dynamic range of the data acquisition system (DAQ) in Raman lidars. However, there exists a deficiency of relatively high dead times among current options, which necessitates an additional calibration procedure for the nonlinearity of the photon counting signal, thus leading to unanticipated errors. A field programmable gate array (FPGA)-based photon counting module has been proposed and implemented in a Raman lidar, offering two operational channels. Through observational experiments, it was determined that this module has an overall dead time of 1.13 ns taking advantage of the high-speed amplifier/discriminator pair and the logic design, a significant improvement compared to the 4.35 ns of a commercially used Licel transient recorder within the same counting rate range. This notably low dead time implies that its output maintains sufficient linearity even at substantially high counting rates. As a result, the need for a dead time calibration procedure prior to signal integration with the analog signal is eliminated, reducing uncertainty in the final integrated signal, and even in the retrieval result. The backscattering result of the comparison between this module and a transient recorder indicates that a more precise performance can be acquired benefiting from this hardware upgrading.

5.
Clin Exp Rheumatol ; 42(5): 1035-1042, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38372719

RESUMEN

OBJECTIVES: Rheumatic and musculoskeletal diseases (RMD) may exhibit different immune responses to novel coronavirus (COVID-19) infection compared to healthy individuals. While previous studies have primarily investigated changes in COVID-19-related antibodies post-vaccination for RMD patients, this study sought to explore the dynamics of SARS-CoV-2 IgG antibodies and neutralising antibodies (NAb) in RMD patients after COVID-19 infection. METHODS: In this longitudinal study, we monitored the SARS-CoV-2 IgG antibodies and NAb levels in RMD patients and healthy controls (HC) at 60 and 90 days post-COVID-19 infection. Chemiluminescent immunoassay was used to detect the levels of novel coronavirus-specific IgG (anti-S1/S2 IgG) antibodies and NAb. RESULTS: A total of 292 RMD patients and 104 HC were enrolled in the study. At both the 60-day and 90-day post-COVID-19 infection, RMD patients exhibited significantly lower levels of anti-S1/S2 IgG and NAb than those in the HC group (p<0.001). The anti-S1/S2 IgG antibody levels remained relatively stable, while the NAb levels in RMD patients could vary greatly between the 60th and 90th days. A logistic regression analysis revealed that the prior administration of glucocorticoids (GC), immunosuppressants, and b/tsDMARDs stood out as independent risk factors associated with reduced anti-S1/S2 IgG and NAb levels, irrespective of the specific RMD subtypes. CONCLUSIONS: GC and anti-rheumatic medications can potentially alter the production of specific antibodies, especially NAb, in RMD patients post-COVID-19 infection. These findings emphasise the importance of continuous monitoring for NAb fluctuations in RMD patients following a COVID-19 infection.


Asunto(s)
Anticuerpos Neutralizantes , Anticuerpos Antivirales , COVID-19 , Inmunoglobulina G , Enfermedades Musculoesqueléticas , Enfermedades Reumáticas , SARS-CoV-2 , Humanos , COVID-19/inmunología , COVID-19/sangre , Enfermedades Reumáticas/inmunología , Enfermedades Reumáticas/tratamiento farmacológico , Enfermedades Reumáticas/sangre , Masculino , Femenino , Persona de Mediana Edad , Inmunoglobulina G/sangre , Inmunoglobulina G/inmunología , SARS-CoV-2/inmunología , Anticuerpos Antivirales/sangre , Estudios Longitudinales , Adulto , Enfermedades Musculoesqueléticas/inmunología , Enfermedades Musculoesqueléticas/sangre , Anticuerpos Neutralizantes/sangre , Anticuerpos Neutralizantes/inmunología , Anciano , Estudios de Casos y Controles
6.
J Cancer Res Clin Oncol ; 150(2): 71, 2024 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-38305890

RESUMEN

PURPOSE: Diabetes mellitus (DM) is the second most common comorbidity in myelodysplastic syndromes (MDS). The purpose of the study was to investigate the clinical characteristics of MDS patients with DM. METHODS: A retrospective analysis was performed on the clinical data of 890 MDS patients with or without DM. Clinical data, including genetic changes, overall survival (OS), leukemia-free survival (LFS) and infection, were analyzed. RESULTS: Among 890 patients, 184 (20.7%) had DM. TET2 and SF3B1 mutations occurred more frequently in the DM group than those in the non-DM group (p = 0.0092 and p = 0.0004, respectively). Besides, DM was an independent risk factor for infection (HR 2.135 CI 1.451-3.110, p = 0.000) in MDS. Compared to non-DM patients, MDS patients with DM had poor OS and LFS (p = 0.0002 and p = 0.0017, respectively), especially in the lower-risk group. While in multivariate analysis, DM did not retain its prognostic significance and the prognostic significance of infection was maintained (HR 2.488 CI 1.749-3.538, p = 0.000). CONCLUSIONS: MDS patients with DM have an inferior prognosis which may due to higher infection incidence, with TET2 and SF3B1 mutations being more frequent in those cases.


Asunto(s)
Diabetes Mellitus , Leucemia , Síndromes Mielodisplásicos , Humanos , Estudios Retrospectivos , Síndromes Mielodisplásicos/genética , Mutación , Factores de Transcripción/genética , Pronóstico , Diabetes Mellitus/epidemiología , Diabetes Mellitus/genética
7.
IEEE Trans Med Imaging ; 43(1): 405-415, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37594875

RESUMEN

This paper investigates how to effectively mine contextual information among sequential images and jointly model them in medical imaging tasks. Different from state-of-the-art methods that model sequential correlations via point-wise token encoding, this paper develops a novel hierarchical pattern-aware tokenization strategy. It handles distinct visual patterns independently and hierarchically, which not only ensures the full flexibility of attention aggregation under different pattern representations but also preserves both local and global information simultaneously. Based on this strategy, we propose a Pattern-Aware Transformer (PATrans) featuring a global-local dual-path pattern-aware cross-attention mechanism to achieve hierarchical pattern matching and propagation among sequential images. Furthermore, PATrans is plug-and-play and can be seamlessly integrated into various backbone networks for diverse downstream sequence modeling tasks. We demonstrate its general application paradigm across four domains and five benchmarks in video object detection and 3D volumetric semantic segmentation tasks, respectively. Impressively, PATrans sets new state-of-the-art across all these benchmarks, i.e., CVC-Video (92.3% detection F1), ASU-Mayo (99.1% localization F1), Lung Tumor (78.59% DSC), Nasopharynx Tumor (75.50% DSC), and Kidney Tumor (87.53% DSC). Codes and models are available at https://github.com/GGaoxiang/PATrans.


Asunto(s)
Neoplasias Pulmonares , Humanos , Semántica
8.
Exp Neurol ; 371: 114585, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-37884185

RESUMEN

AIMS: Osteopontin (OPN) has demonstrated neuroprotective effects in various stroke models. Its role in neuroinflammation after brain injury remains to be elucidated. This study aims to clarify the effect of OPN on neuroinflammation, particularly on the functional states of microglia after subarachnoid hemorrhage (SAH). METHODS: 77 rats were randomly divided into the following groups: Sham, SAH 24 h, SAH + rOPN, SAH + Vehicle (PBS), SAH + OPN siRNA, and SAH + Scr siRNA, SAH + rOPN+Fib-14 and SAH + rOPN+DMSO. Modified Garcia and beam balance tests were used to evaluate neurobehavioral outcomes. Semi-quantitative immunofluorescence staining was performed to measure expression of myeloperoxidase (MPO) and microglia activation state markers CD16, CD206 after SAH and recombinant OPN treatment. The quantification of microglia activation and functional markers CD16, CD206, TNF-α and IL-10 were further evaluated using Western-blotting. RESULTS: Nasal administration of rOPN improved neurological dysfunction, attenuated neutrophil infiltration, and decreased expression of phenotypic and functional markers of pro-inflammatory microglia CD16 and TNF-α. It also promoted an anti-inflammatory microglial state, as evidenced by increased expression of CD206 and IL-10. Furthermore, after blocking the phosphorylation of FAK signaling, the effects of rOPN on microglial activation states were partially reversed. The downstream pathways of STAT3 and NF-κB also exhibited consistent changes, suggesting the involvement of the STAT3 and NF-κB pathways in OPN's modulation of microglial activation via integrin-FAK signaling. CONCLUSION: OPN attenuates inflammatory responses after SAH by promoting an anti-inflammatory microglial state, potentially mediated through the integrin-FAK-STAT3 and NF-κB signaling pathways.


Asunto(s)
Osteopontina , Hemorragia Subaracnoidea , Ratas , Animales , Osteopontina/uso terapéutico , Osteopontina/metabolismo , Osteopontina/farmacología , Ratas Sprague-Dawley , FN-kappa B/metabolismo , Interleucina-10 , Microglía/metabolismo , Hemorragia Subaracnoidea/complicaciones , Hemorragia Subaracnoidea/tratamiento farmacológico , Hemorragia Subaracnoidea/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo , Enfermedades Neuroinflamatorias , Antiinflamatorios/farmacología , Integrinas/metabolismo , Integrinas/uso terapéutico , ARN Interferente Pequeño/farmacología , Modelos Animales de Enfermedad
9.
Medicine (Baltimore) ; 102(45): e35921, 2023 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-37960720

RESUMEN

BACKGROUND: To investigate the efficacy of technology-assisted rehabilitation compared to that of usual care programs after total hip arthroplasty (THA) through randomized controlled trials (RCTs). METHODS: The Medline (PubMed), Cochrane Library, Embase and Web of Science databases were searched for RCTs regarding the efficacy of technology-assisted rehabilitation following THA. Data were analyzed using Stata 12.0 software. RESULTS: Eleven RCTs involving 1327 patients were included in the meta-analysis. The pooled effect size showed that compared to usual care, telerehabilitation significantly improved the Harris score (standardized mean difference [SMD] 0.74, 95% confidence interval [CI] 0.58 to 0.90) and functional independence measure (FIM) score (SMD 1.26, 95% CI 0.48 to 2.03). In addition, video-based therapy could significantly improve walk test results (SMD 0.43, 95% CI 0.11 to 0.75). CONCLUSION: The findings suggest that technology-assisted rehabilitation, especially telerehabilitation, have been shown to improve the physical function of patients following THA compared to conventional rehabilitation. More robust studies are needed to validate the long-term efficacy and safety of innovative technology-assisted training strategies.


Asunto(s)
Artroplastia de Reemplazo de Cadera , Telerrehabilitación , Humanos , Artroplastia de Reemplazo de Cadera/efectos adversos , Actividades Cotidianas , Telerrehabilitación/métodos , Caminata
10.
Sci Adv ; 9(48): eadi7375, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-38019913

RESUMEN

Myelodysplastic syndrome (MDS) is a group of clonal hematopoietic neoplasms originating from hematopoietic stem progenitor cells (HSPCs). We previously identified frequent roundabout guidance receptor 1 (ROBO1) mutations in patients with MDS, while the exact role of ROBO1 in hematopoiesis remains poorly delineated. Here, we report that ROBO1 deficiency confers MDS-like disease with anemia and multilineage dysplasia in mice and predicts poor prognosis in patients with MDS. More specifically, Robo1 deficiency impairs HSPC homeostasis and disrupts HSPC pool, especially the reduction of megakaryocyte erythroid progenitors, which causes a blockage in the early stages of erythropoiesis in mice. Mechanistically, transcriptional profiling indicates that Cdc42, a member of the Rho-guanosine triphosphatase family, acts as a downstream target gene for Robo1 in HSPCs. Overexpression of Cdc42 partially restores the self-renewal and erythropoiesis of HSPCs in Robo1-deficient mice. Collectively, our result implicates the essential role of ROBO1 in maintaining HSPC homeostasis and erythropoiesis via CDC42.


Asunto(s)
Eritropoyesis , Síndromes Mielodisplásicos , Animales , Humanos , Ratones , Eritropoyesis/genética , Síndromes Mielodisplásicos/genética , Proteínas del Tejido Nervioso/genética , Pronóstico , Receptores Inmunológicos/genética , Proteínas Roundabout
11.
BMC Bioinformatics ; 24(1): 434, 2023 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-37968615

RESUMEN

BACKGROUND: In the field of biology and medicine, the interpretability and accuracy are both important when designing predictive models. The interpretability of many machine learning models such as neural networks is still a challenge. Recently, many researchers utilized prior information such as biological pathways to develop neural networks-based methods, so as to provide some insights and interpretability for the models. However, the prior biological knowledge may be incomplete and there still exists some unknown information to be explored. RESULTS: We proposed a novel method, named PathExpSurv, to gain an insight into the black-box model of neural network for cancer survival analysis. We demonstrated that PathExpSurv could not only incorporate the known prior information into the model, but also explore the unknown possible expansion to the existing pathways. We performed downstream analyses based on the expanded pathways and successfully identified some key genes associated with the diseases and original pathways. CONCLUSIONS: Our proposed PathExpSurv is a novel, effective and interpretable method for survival analysis. It has great utility and value in medical diagnosis and offers a promising framework for biological research.


Asunto(s)
Conocimiento , Medicina , Aprendizaje Automático , Análisis de Supervivencia , Estudios de Asociación Genética
12.
Int J Biochem Cell Biol ; 165: 106480, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37884171

RESUMEN

The occurrence of autophagy dysregulation is vital in the development of myelodysplastic syndrome and its transformation to acute myeloid leukemia. However, the mechanisms are largely unknown. Here, we have investigated the mechanism of the bcl6 corepressor mutation in myelodysplastic syndrome development and its transformation to acute myeloid leukemia. We identified a novel pathway involving histone deacetylase 6 and forkhead box protein O1, which leads to autophagy defects following the bcl6 corepressor mutation. And this further causes apoptosis and cell cycle arrest. The bcl6 corepressor-mutation-repressed autophagy resulted in the accumulation of damaged mitochondria, DNA, and reactive oxygen species in myelodysplastic syndrome cells, which could then lead to genomic instability and spontaneous mutation. Our results suggest that the bcl6 corepressor inactivating mutations exert pro-carcinogenic effects through survival strike, which is only an intermediate process. These findings provide mechanistic insights into the role of the bcl6 corepressor gene in myelodysplastic syndrome.


Asunto(s)
Leucemia Mieloide Aguda , Síndromes Mielodisplásicos , Humanos , Factores de Transcripción/metabolismo , Síndromes Mielodisplásicos/genética , Mutación , Autofagia/genética , Proteínas Co-Represoras/genética
13.
World Neurosurg ; 180: e686-e699, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37821029

RESUMEN

BACKGROUND: Controversy exists regarding the superiority of the performance of prognostic tools based on advanced machine learning (ML) algorithms for patients with aneurysmal subarachnoid hemorrhage (aSAH). However, it is unclear whether ML prognostic models will benefit patients due to the lack of a comprehensive assessment. We aimed to develop and evaluate ML models for predicting unfavorable functional outcomes for aSAH patients and identify the model with the greatest performance. METHODS: In this retrospective study, a dataset of 955 patients with aSAH was used to construct and validate prognostic models for functional outcomes assessed using the modified Rankin scale during a follow-up period of 3-6 months. Clinical scores and clinical and radiological features on admission and secondary complications were used to construct models based on 5 ML algorithms (i.e., logistic regression [LR], k-nearest neighbor, extreme gradient boosting, random forest, and artificial neural network). For evaluation among the models, the area under the receiver operating characteristic curve, area under the precision-recall curve, calibration curve, and decision curve analysis were used. RESULTS: Composite models had significantly higher area under the receiver operating characteristic curves than did simple models in predicting unfavorable functional outcomes. Compared with other composite models (random forest and extreme gradient boosting) with good calibration, LR had the highest area under the precision-recall score and showed the greatest benefit in decision curve analysis. CONCLUSIONS: Of the 5 studied ML models, the conventional LR model outperformed the advanced algorithms in predicting the prognosis and could be a useful tool for health care professionals.


Asunto(s)
Hemorragia Subaracnoidea , Humanos , Pronóstico , Hemorragia Subaracnoidea/diagnóstico por imagen , Hemorragia Subaracnoidea/cirugía , Estudios Retrospectivos , Aprendizaje Automático , Curva ROC
15.
Front Pharmacol ; 14: 1253520, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37745052

RESUMEN

Background: Clinical decision support tools (CDSs) have been demonstrated to enhance the accuracy of antibiotic prescribing among physicians. However, their effectiveness in reducing inappropriate antibiotic use for respiratory tract infections (RTI) is controversial. Methods: A literature search in 3 international databases (Medline, Web of science and Embase) was conducted before 31 May 2023. Relative risk (RR) and corresponding 95% confidence intervals (CI) were pooled to evaluate the effectiveness of intervention. Summary effect sizes were calculated using a random-effects model due to the expected heterogeneity (I 2 over 50%). Results: A total of 11 cluster randomized clinical trials (RCTs) and 5 before-after studies were included in this meta-analysis, involving 900,804 patients met full inclusion criteria. Among these studies, 11 reported positive effects, 1 reported negative results, and 4 reported non-significant findings. Overall, the pooled effect size revealed that CDSs significantly reduced antibiotic use for RTIs (RR = 0.90, 95% CI = 0.85 to 0.95, I 2 = 96.10%). Subgroup analysis indicated that the intervention duration may serve as a potential source of heterogeneity. Studies with interventions duration more than 2 years were found to have non-significant effects (RR = 1.00, 95% CI = 0.96 to 1.04, I 2 = 0.00%). Egger's test results indicated no evidence of potential publication bias (p = 0.287). Conclusion: This study suggests that CDSs effectively reduce inappropriate antibiotic use for RTIs among physicians. However, subgroup analysis revealed that interventions lasting more than 2 years did not yield significant effects. These findings highlight the importance of considering intervention duration when implementing CDSs. Systematic Review Registration: https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42023432584, Identifier: PROSPERO (CRD42023432584).

16.
Medicine (Baltimore) ; 102(38): e35036, 2023 Sep 22.
Artículo en Inglés | MEDLINE | ID: mdl-37746952

RESUMEN

BACKGROUND: This study was conducted to explore the potential relationship between interleukin-10 (IL-10) and obstructive sleep apnea hypopnea syndrome (OSAHS). METHODS: All the related research articles published before October 2022 were retrieved through the online database (EMBASE, VIP, Wan Fang, Web of Science, PubMed, and CNKI). Stata 11.0 software was used to calculate the standard mean difference (SMD) of the continuous variable and 95% confidence interval (CI). Expression profiles GSE38792 and GSE135917 were acquired from Gene Expression Omnibus (GEO) database, respectively. The expression of IL-10 mRNA in subcutaneous adipose tissue and visceral adipose tissue of OSAHS patients and healthy subjects was extracted by R software to verify the difference in IL-10 between the 2 groups. RESULTS: The IL-10 level in the plasma of people with and without OSAHS (STD Mean Difference (SMD) = -0.68, 95% CI = -1.58 to 0.21, I2 = 94.3%, P = .136) was the same. There was also no difference in IL-10 levels in serum between people with and without OSAHS (SMD = -0.12, 95% CI = -0.55 to 0.32, I2 = 94.4%, P = .591). In addition, the subjects were divided into different subgroups for meta-analysis according to race, body mass index, age, study type, and disease severity. Based on the outcomes, no notable difference was observed in the plasma/serum IL-10 level between the OSAHS subgroups and the control group. The results of bioinformatics analysis indicated that there was no significant difference in the expression of IL-10 mRNA in subcutaneous adipose tissue and visceral adipose tissue between patients with OSAHS and those in the control group. CONCLUSION: The current meta-analysis highlighted that IL-10 levels between patients with OSAHS and healthy people had no difference.


Asunto(s)
Interleucina-10 , Apnea Obstructiva del Sueño , Humanos , Interleucina-10/genética , Apnea Obstructiva del Sueño/genética , Síndrome , Índice de Masa Corporal , ARN Mensajero
17.
Environ Sci Technol ; 57(38): 14226-14236, 2023 09 26.
Artículo en Inglés | MEDLINE | ID: mdl-37713595

RESUMEN

Vertical distribution of phytoplankton is crucial for assessing the trophic status and primary production in inland waters. However, there is sparse information about phytoplankton vertical distribution due to the lack of sufficient measurements. Here, we report, to the best of our knowledge, the first Mie-fluorescence-Raman lidar (MFRL) measurements of continuous chlorophyll a (Chl-a) profiles as well as their parametrization in inland water. The lidar-measured Chl-a during several experiments showed good agreement with the in situ data. A case study verified that MFRL had the potential to profile the Chl-a concentration. The results revealed that the maintenance of subsurface chlorophyll maxima (SCM) was influenced by light and nutrient inputs. Furthermore, inspired by the observations from MFRL, an SCM model built upon surface Chl-a concentration and euphotic layer depth was proposed with root mean square relative difference of 16.5% compared to MFRL observations, providing the possibility to map 3D Chl-a distribution in aquatic ecosystems by integrated active-passive remote sensing technology. Profiling and modeling Chl-a concentration with MFRL are expected to be of paramount importance for monitoring inland water ecosystems and environments.


Asunto(s)
Clorofila , Ecosistema , Clorofila A , Fluorescencia , Fitoplancton , Agua
18.
Cell Commun Signal ; 21(1): 175, 2023 07 21.
Artículo en Inglés | MEDLINE | ID: mdl-37480108

RESUMEN

BACKGROUND: The phagocytosis and homeostasis of microglia play an important role in promoting blood clearance and improving prognosis after subarachnoid hemorrhage (SAH). LC3-assocaited phagocytosis (LAP) contributes to the microglial phagocytosis and homeostasis via autophagy-related components. With RNA-seq sequencing, we found potential signal pathways and genes which were important for the LAP of microglia. METHODS: We used an in vitro model of oxyhemoglobin exposure as SAH model in the study. RNA-seq sequencing was performed to seek critical signal pathways and genes in regulating LAP. Bioparticles were used to access the phagocytic ability of microglia. Western blot (WB), immunoprecipitation, quantitative polymerase chain reaction (qPCR) and immunofluorescence were performed to detect the expression change of LAP-related components and investigate the potential mechanisms. RESULTS: In vitro SAH model, there were increased inflammation and decreased phagocytosis in microglia. At the same time, we found that the LAP of microglia was inhibited in all stages. RNA-seq sequencing revealed the importance of P38 MAPK signal pathway and DAPK1 in regulating microglial LAP. P38 was found to regulate the expression of DAPK1, and P38-DAPK1 axis was identified to regulate the LAP and homeostasis of microglia after SAH. Finally, we found that P38-DAPK1 axis regulated expression of BECN1, which indicated the potential mechanism of P38-DAPK1 axis regulating microglial LAP. CONCLUSION: P38-DAPK1 axis regulated the LAP of microglia via BECN1, affecting the phagocytosis and homeostasis of microglia in vitro SAH model. Video Abstract.


Asunto(s)
Microglía , Hemorragia Subaracnoidea , Humanos , Fagocitosis , Autofagia , Inflamación , Proteínas Quinasas Asociadas a Muerte Celular
19.
Research (Wash D C) ; 6: 0201, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37475723

RESUMEN

Measuring the characteristics of seawater constituent is in great demand for studies of marine ecosystems and biogeochemistry. However, existing techniques based on remote sensing or in situ samplings present various tradeoffs with regard to the diversity, synchronism, temporal-spatial resolution, and depth-resolved capacity of their data products. Here, we demonstrate a novel oceanic triple-field-of-view (FOV) high-spectral-resolution lidar (HSRL) with an iterative retrieval approach. This technique provides, for the first time, comprehensive, continuous, and vertical measurements of seawater absorption coefficient, scattering coefficient, and slope of particle size distribution, which are validated by simulations and field experiments. Furthermore, it depicts valuable application potentials in the accuracy improvement of seawater classification and the continuous estimation of depth-resolved particulate organic carbon export. The triple-FOV HSRL with high performance could greatly increase the knowledge of seawater constituents and promote the understanding of marine ecosystems and biogeochemistry.

20.
J Clin Med ; 12(11)2023 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-37298050

RESUMEN

Objective. The search for methods by which to predict the risks of cerebral hyperperfusion syn-drome (CHS) in adults with moyamoya disease (MMD), including those utilizing new biomarkers, still deserves further research. The objective of this study was to investigate the association between the hemodynamics of parasylvian cortical arteries (PSCAs) and postoperative CHS. Methods. A consecutive number of adults with MMD who had undergone direct bypass between September 2020 and December 2022 were recruited. Intraoperative microvascular doppler ultrasonography (MDU) was performed to evaluate the hemodynamics of PSCAs. The intraoperative flow direction, mean value of velocity (MVV) of recipient artery (RA) and bypass graft were recorded. According to flow direction after bypass, RA was divided into entering sylvian (RA.ES) and leaving sylvian (RA.LS) subtypes. Univariate, multivariate, and ROC analyses of the risk factors for postoperative CHS were performed. Results. A total of 16 (15.09%) cases in 106 consecutive hemispheres (101 patients) sat-isfied the postoperative CHS criteria. According to univariate analysis, advanced Suzuki stage, MVV of RA before bypass, and fold increase of MVV in RA.ES after bypass were significantly associated with postoperative CHS (p < 0.05). Multivariate analysis indicated that left-operated hemisphere (OR (95%CI), 4.58 (1.05-19.97), p = 0.043), advanced Suzuki stage (OR (95%CI), 5.47 (1.99-15.05), p = 0.017), and fold increase of MVV in RA.ES (OR (95%CI), 1.17 (1.06-1.30), p = 0.003) were statistically significantly associated with the occurrence of CHS. The cut-off value of fold increase of MVV in RA.ES was 2.7-fold (p < 0.05). Conclusions. Left-operated hemisphere, advanced Suzuki stage, and postoperative fold increase of MVV in RA.ES were potential risk factors for postoperative CHS. Intraoperative MDU was useful for evaluating hemodynamics and predicting CHS.

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