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1.
J Neurophysiol ; 131(3): 556-561, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38324895

RESUMO

Sport-related concussion (SRC) is known to disrupt neurohemodynamic activity, cardiac function, and blood pressure (BP) autoregulation. This study aims to observe changes in cerebrovascular and cardiovascular responses during controlled respiration after sustaining an SRC. University varsity athletes (n = 81) completed a preseason physiological assessment and were followed up within 5 days of sustaining an SRC. During preseason and follow-up assessments, participants' continuous beat-to-beat BP was collected by finger photoplethysmography, and right prefrontal cortex oxygenation was collected using near-infrared spectroscopy (NIRS). Participants completed 5 min of seated rest and 5 min of a 6-breaths per minute controlled breathing protocol (5 s inhale and 5 s exhale; 0.10 Hz). Wavelet transformation was applied to the NIRS and BP signals, separating them into respiratory (0.10-0.6 Hz) and cardiac (0.6-2 Hz) frequency intervals. Of the 81 participants, 74 had a usable BP signal, 43 had usable NIRS signals, and 28 had both usable BP and NIRS signals. Wavelet amplitudes were calculated and coherence between NIRS and BP on the 28 participants were assessed. There was a significant (P < 0.05) decrease in oxygenated hemoglobin amplitude from 0.062 to 0.054 Hz and hemoglobin difference amplitude from 0.059 to 0.051 Hz, both at the respiratory (0.10-0.6 Hz) frequency interval, from preseason to acute SRC, respectively. Therefore, during controlled respiration, there was a reduction in intensity at the respiratory band, suggesting a protective, reduced respiratory contribution to cerebral hemodynamic activity following acute SRC.NEW & NOTEWORTHY This study investigated cerebral hemodynamic activity following sport-related concussion. Prefrontal cortex oxygenation was assessed by near-infrared spectroscopy (NIRS) during a controlled breathing protocol. Wavelet transformation of the NIRS signals showed significant decreases in HbO2 and HbD amplitude at the respiratory frequency interval (0.10-0.6 HZ) from preseason baseline to acute concussion. These results suggest a decreased respiratory contribution to cerebral hemodynamic activity following acute concussion.


Assuntos
Concussão Encefálica , Hemodinâmica , Humanos , Córtex Pré-Frontal , Hemoglobinas , Respiração , Circulação Cerebrovascular/fisiologia
2.
BMC Neurol ; 24(1): 49, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38291381

RESUMO

The growing incidence of Parkinson's Disease (PD) is a major burden on the healthcare system. PD is caused by the degeneration of dopaminergic neurons and is known for its effects on motor function and sleep. Sleep is vital for maintaining proper homeostasis and clearing the brain of metabolic waste. Adequate time spent in each sleep stage can help maintain homeostatic function; however, patients with PD appear to exhibit sleep impairments. Although medications enhance the function of remaining dopaminergic neurons and reduce motor symptoms, their potential to improve sleep is still under question. Recently, research has shifted towards exercise protocols to help improve sleep in patients with PD. This review aims to provide an overview of how sleep is impaired in patients with PD, such as experiencing a reduction in time spent in slow-wave sleep, and how exercise can help restore normal sleep function. A PubMed search summarized the relevant research on the effects of aerobic and resistance exercise on sleep in patients with PD. Both high and low-intensity aerobic and resistance exercises, along with exercises related to balance and coordination, have been shown to improve some aspects of sleep. Neurochemically, sleeping leads to an increase in toxin clearance, including α-synuclein. Furthermore, exercise appears to enhance the concentration of brain-derived neurotrophic factors, which has preliminary evidence to suggest correlations to time spent in slow-wave sleep. More research is needed to further elucidate the physiological mechanism pertaining to sleep and exercise in patients with PD.


Assuntos
Doença de Parkinson , Humanos , Doença de Parkinson/complicações , Qualidade do Sono , Exercício Físico , Terapia por Exercício/métodos , Encéfalo
3.
J Appl Microbiol ; 131(2): 634-646, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33411963

RESUMO

AIM: To investigate the occurrence of ESBL and colistin-resistant E. coli and its genotypic characterization and identification of virulence determinants in cases of bovine mastitis in three provinces of China. MATERIALS AND METHODS: Five hundred and thirty-five milk samples presenting mastitis symptoms were screened for the presence of ESBL, colistin-resistant and different virulence genes. Susceptibility testing was identified by the micro-dilution method. Escherichia coli isolates were used to detect ESBL genes (blaCTX-M , blaSHV and blaTEM ) and colistin-resistant genes mcr-(1-9). Multiplex PCR approach was used for the detection of major blaCTX-M groups, different phylogroups and virulence genes. The clonal relationship was then evaluated with MLST, MLSA and PFGE. RESULTS: Multi-drug resistance (MDR) was found in more than 85% of ESBL and colistin-resistant E. coli isolates. Genotypic characterization showed a dominance of the blaCTX-M-1 group, and the most prevalent alleles observed were blaCTX-M-28 (38·37%), blaCTX-M-14 (17·44%), blaCTX-M-66 (13·95%) and blaCTX-M-55 (10·46%). The targeted virulence genes were detected in 97·89% of isolates. Sequence types ST58 and ST410 were the most predominant (2/20 = 20%). The majority of the E. coli isolates carrying ESBL and mcr-1 were clonally unrelated. CONCLUSION: High level of association was observed between ESBL-producing and COL-resistance in E. coli of bovine mastitis. SIGNIFICANCE AND IMPACT OF THE STUDY: To the best of our knowledge, this is the first report which shows the genetic diversity of ESBL and mcr-1, and various virulent features of E. coli strains isolated from bovine clinical mastitis in three different provinces of China. The major carriers of the blaCTX-M-1 and blaCTX-M-9 were blaCTX-M-28 and blaCTX-M-14 alleles respectively. The association of ESBL-producing E. coli with mcr-1 is of particular concern.


Assuntos
Infecções por Escherichia coli , Proteínas de Escherichia coli , Escherichia coli , Mastite Bovina , Fatores de Virulência , Animais , Antibacterianos/farmacologia , Bovinos , China , Escherichia coli/genética , Escherichia coli/patogenicidade , Infecções por Escherichia coli/veterinária , Proteínas de Escherichia coli/genética , Feminino , Mastite Bovina/microbiologia , Leite/microbiologia , Tipagem de Sequências Multilocus , Plasmídeos , Fatores de Virulência/genética , beta-Lactamases/genética
4.
Development ; 144(17): 3031-3041, 2017 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-28743800

RESUMO

The epithelial lining of the fallopian tube is vital for fertility, providing nutrition to gametes and facilitating their transport. It is composed of two major cell types: secretory cells and ciliated cells. Interestingly, human ovarian cancer precursor lesions primarily consist of secretory cells. It is unclear why secretory cells are the dominant cell type in these lesions. Additionally, the underlying mechanisms governing fallopian tube epithelial homoeostasis are unknown. In the present study, we showed that across the different developmental stages of mouse oviduct, secretory cells are the most frequently dividing cells of the oviductal epithelium. In vivo genetic cell lineage tracing showed that secretory cells not only self-renew, but also give rise to ciliated cells. Analysis of a Wnt reporter mouse model and various Wnt target genes showed that the Wnt signaling pathway is involved in oviductal epithelial homoeostasis. By developing two triple-transgenic mouse models, we showed that Wnt/ß-catenin signaling is essential for self-renewal as well as the differentiation of secretory cells. In summary, our results provide mechanistic insight into oviductal epithelial homoeostasis.


Assuntos
Linhagem da Célula , Autorrenovação Celular , Rastreamento de Células , Cílios/metabolismo , Oviductos/citologia , Oviductos/metabolismo , Animais , Diferenciação Celular , Proliferação de Células , Epitélio/patologia , Tubas Uterinas/patologia , Feminino , Predisposição Genética para Doença , Humanos , Camundongos Endogâmicos C57BL , Neoplasias Ovarianas/patologia , Fator de Transcrição PAX8/metabolismo , Fatores de Risco , Via de Sinalização Wnt , beta Catenina/metabolismo
5.
BMC Plant Biol ; 20(1): 171, 2020 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-32303179

RESUMO

BACKGROUND: Chickpea is one of the major legume crops being cultivated in the arid and semi-arid regions of Pakistan. It is mainly grown on the marginal areas where, terminal drought stress is one of the serious threats to its productivity. For defining the appropriate selection criteria for screening drought tolerant chickpea genotypes, present study was conducted. Distinct chickpea germplasm was collected from different pulses breeding institutes of Pakistan and evaluated for drought tolerance at germination and early seedling stages, furthermore, at late vegetative growth stages physiochemical traits and multi-environment yield performance were also tested. RESULTS: Chickpea genotypes under different environments, were significantly varied for different seedling traits, physio-chemical attributes and seed yield. Genotypes showing drought tolerance by performing better at an early seedling stages were not correspondingly high yielding. Screening for drought tolerance on seed yield basis is the most appropriate trait to develop the drought tolerant as well as high yielding chickpea genotypes. Results confirmed that traits of early growth stages were not reflecting the drought tolerance at terminal growth stages and also did not confer high yielding. NIAB-rain fed environment proved ideal in nature to screen the chickpea genotypes whereas, NIAB-lysimeter and Kalur Kot was least effective for selecting genotypes with high seed yield. Genotypes D0091-10, K010-10, D0085-10, K005-10, D0078-10, 08AG016, 08AG004, D0080-10, 09AG002, K002-10 and D0099-10 were high yielding and drought tolerant based on their performance across multiple hotspot environments. CONCLUSIONS: The selected genotypes are intended for further evaluation for varietal approval to recommend for general cultivation on farmer fields in drought hit areas of Pakistan. Among physio-biochemical traits, higher proline, glycine betain, RWC and CMS were reflecting the higher capability to tolerate the drought stress in chickpea. Drought sensitive genotypes (K0037-10, 2204, K0052-10, 09AG015, K0042-10, CM709/06, K0068-10, K004-10, K0026-10 and K0063-10) were also identified in present study which were resourceful asset for using as contrasting parents in hybridization programs. To our knowledge, this is first report using an integrated approach involving, physio-biochemical indices, and multi-environmental yield trials, for comparison, screening and selection of chickpea genotypes for drought tolerance.


Assuntos
Cicer/fisiologia , Secas , Genótipo , Seleção Genética/fisiologia , Estresse Fisiológico/genética , Cicer/genética , Cicer/crescimento & desenvolvimento , Meio Ambiente
6.
Phys Chem Chem Phys ; 22(18): 10351-10359, 2020 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-32365147

RESUMO

Vertical stacking of two-dimensional materials into layered van der Waals heterostructures has recently been considered as a promising candidate for photocatalytic and optoelectronic devices because it can combine the advantages of the individual 2D materials. Janus transition metal dichalcogenides (JTMDCs) have emerged as an appealing photocatalytic material due to the desirable electronic properties. Hence, in this work, we systematically investigate the geometric features, electronic properties, charge density difference, work function, band alignment and photocatalytic properties of ZnO-JTMDC heterostructures using first-principles calculations. Due to the different kinds of chalcogen atoms on both sides of JTMDC monolayers, two different possible stacking patterns of ZnO-JTMDC heterostructures have been constructed and considered. We find that all these stacking patterns of ZnO-JTMDC heterostructures are dynamically and energetically feasible. Moreover, both ZnO-MoSSe and ZnO-WSSe heterostructures are indirect band gap semiconductors and present type-I and type-II band alignments for model-I and model-II, respectively. The Rashba spin polarization of the ZnO-WSSe heterostructure for model-I is greater than that in the others. Furthermore, valence (conduction) band edge potentials are calculated to understand the photocatalytic behavior of these systems. Energetically favorable band edge positions in ZnO-Janus heterostructures make them suitable for water splitting at zero pH. We found that the ZnO-Janus heterostructures are promising candidates for water splitting with conduction and valence band edges positioned just outside of the redox interval.

7.
Acta Virol ; 63(1): 26-35, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30879310

RESUMO

Whitefly-transmitted viruses of the genus Begomovirus (the family Geminiviridae) have become a limiting factor for agricultural productivity in many warmer parts of the world. The economies of Pakistan and India have, since the early 1990s, suffered losses due to cotton leaf curl disease (CLCuD). The disease is caused by begomoviruses, the most important of which at this time is cotton leaf curl Kokhran virus strain Burewala (CLCuKoV-Bu), and a disease-specific betasatellite, cotton leaf curl Multan betasatellite (CLCuMuB). Efforts to minimize losses due to CLCuD rely mainly on the use of insecticides to kill the whitefly vector; no resistant cotton varieties are currently commercially available. The study described here has investigated RNA interference technology for its potential to yield resistance against CLCuKoV-Bu and three other begomoviruses; CLCuKoV, tomato leaf curl New Delhi virus (ToLCNDV) and Pedilanthus leaf curl virus (PeLCV). Three fragments of the virion-sense V2 gene of CLCuKoV-Bu were transformed into Nicotiana benthamiana in antisense orientation and transgenic lines expressing virus-specific short RNAs were assessed for their ability to yield resistance. Only CLCuKoV-Bu with the V2 sequence closest to the promoter was resistant. Inoculation of CLCuKoV-Bu with CLCuMuB into transgenic plants did not significantly affect the outcome, although viral DNA was detected in number of plants, suggesting that the betasatellite may impair RNAi resistance. Overall the results indicate that targeting the 5' end of V2 gene using antisense-RNA has the potential to deliver resistance against begomoviruses and that RNAi-based resistance imparts some degree of resistance to heterologous viruses. Keywords: geminivirus; begomovirus; RNAi; resistance; CLCuKoV-Burewala; CLCuMuB.


Assuntos
Begomovirus , Resistência à Doença , Nicotiana , Begomovirus/genética , Begomovirus/fisiologia , DNA Viral/genética , Resistência à Doença/genética , Doenças das Plantas/genética , Doenças das Plantas/virologia , Plantas Geneticamente Modificadas , Interferência de RNA , Nicotiana/genética , Nicotiana/virologia
8.
Environ Monit Assess ; 191(12): 735, 2019 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-31707527

RESUMO

Biochar pyrolyzed at 800 °C from banana (Bb) and orange peels (OPb) was applied for sorption of methylene blue (MB) dye in a batch system. OPb showed better affinity for MB dye than Bb with rapid increase in sorption capacity and percent removal for both biochars attaining equilibrium at 30 min. Chemisorption was suggested as the rate limiting step based on the best fitting of the pseudo-second-order reaction kinetics to the batch adsorption data. Linear increase in sorption capacity was seen as the initial MB dye concentration increased from 50 to 300 mg g-1 with a 40 % decrease in removal efficiency. An increase of 90 mg g-1 in sorption capacity for both biochars with a 15 and 30 % increase in removal efficiency for OPb and Bb, respectively, was observed after increasing the solution pH from 2 to 6 or 8. An increase in sorption capacity of about 150 mg g-1 was seen by increasing the biochar dose from 0.1 to 0.5 g. Langmuir isotherm model represented the adsorption data well as reflected by the high values of R2 (0.99) when using both biochar, while least representation of adsorption data was seen in H-J isotherm as estimated from very low R2 (0.6-0.66) for both types of biochar. An endothermic nature of MB dye sorption was suggested based on the linear increase in sorption capacity with an increase in solution temperature from 30 to 60 °C. This was further confirmed by the observed positive changes in standard entropy and standard enthalpy while negative values of Gibbs-free energies proposed the non-spontaneous natures of MB dye sorption on to both biochars. The effective sorption of MB dye demonstrated the potential of plant-based biochar as economically viable adsorbents for MB dye.


Assuntos
Carvão Vegetal/química , Azul de Metileno/química , Poluentes Químicos da Água/química , Adsorção , Biomassa , Citrus sinensis , Monitoramento Ambiental , Concentração de Íons de Hidrogênio , Cinética , Musa , Termodinâmica , Água , Purificação da Água
9.
Dev Biol ; 423(2): 138-151, 2017 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-28153546

RESUMO

In mice, implantation always occurs towards the antimesometrial side of the uterus, while the placenta develops at the mesometrial side. What determines this particular orientation of the implanting blastocyst remains unclear. Uterine glands are critical for implantation and pregnancy. In this study, we showed that uterine gland development and active Wnt signaling activity is limited to the antimesometrial side of the uterus. Dkk2, a known antagonist of Wnt signaling, is only present at the mesometrial side of the uterus. Imaging of whole uterus, thick uterine sections (100-1000µm), and individual glands revealed that uterine glands are simple tubes with branches that are directly connected to the luminal epithelium and are only present towards the antimesometrial side of the uterus. By developing a unique mouse model targeting the uterine epithelium, we demonstrated that Wnt/ß-catenin signaling is essential for prepubertal gland formation and normal implantation, but dispensable for postpartum gland development and regeneration. Our results for the first time have provided a probable explanation for the antimesometrial bias for implantation.


Assuntos
Epitélio/embriologia , Útero/embriologia , Via de Sinalização Wnt , Animais , Implantação do Embrião/efeitos dos fármacos , Epitélio/efeitos dos fármacos , Epitélio/metabolismo , Feminino , Fertilidade/efeitos dos fármacos , Hibridização In Situ , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Camundongos Endogâmicos C57BL , Período Pós-Parto/efeitos dos fármacos , Progesterona/farmacologia , Maturidade Sexual/efeitos dos fármacos , Útero/efeitos dos fármacos , Útero/metabolismo , Via de Sinalização Wnt/efeitos dos fármacos , beta Catenina/metabolismo
10.
Dev Biol ; 412(2): 234-49, 2016 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-26934381

RESUMO

Organ shape and size are important determinants of their physiological functions. Epithelial tubes are anlagen of many complex organs. How these tubes acquire their complex shape and size is a fundamental question in biology. In male mice, the Wolffian duct (WD; postnatally known as epididymis) undergoes an astonishing transformation, where a straight tube only a few millimetres long elongates to over 1000 times its original length and fits into a very small space, due to extensive coiling of epithelium, to perform the highly specialized function of sperm maturation. Defective coiling disrupts sperm maturation and leads to male infertility. Recent work has shown that epithelial cell proliferation is a major driver of WD coiling. Still, very little is known about the molecular signals involved in this process. Testicular androgens are known regulators of WD development. However, epithelial androgen receptor signalling is dispensable for WD coiling. In this study, we have shown that Wnt signalling is highly active in the entire WD epithelium during its coiling, and is limited to only a few segments of the epididymis in later life. Pharmacological and genetic suppression of Wnt signalling inhibited WD coiling by decreasing cell proliferation and promoting apoptosis. Comparative gene expression analysis identified Fibroblast growth factor 7 (Fgf7) as a prime Wnt target gene involved in WD coiling and in vitro treatment with Fgf7 protein increased coiling of WDs. In summary, our work has established that epithelial canonical Wnt signalling is a critical regulator of WD coiling and its precise regulation is essential for WD/epididymal differentiation.


Assuntos
Epididimo/metabolismo , Epitélio/metabolismo , Via de Sinalização Wnt/genética , Ductos Mesonéfricos/metabolismo , Animais , Epididimo/embriologia , Epitélio/embriologia , Fator 7 de Crescimento de Fibroblastos/genética , Fator 7 de Crescimento de Fibroblastos/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Masculino , Camundongos da Linhagem 129 , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Microscopia de Fluorescência , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Ductos Mesonéfricos/embriologia , beta Catenina/genética , beta Catenina/metabolismo
11.
Water Sci Technol ; 76(7-8): 1805-1815, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28991795

RESUMO

Adsorption of the hazardous dye malachite green (MG) by Acacia nilotica (AN) waste was investigated. Batch process variables for the adsorption of MG by AN were optimized. The mechanisms involved in the adsorption of MG by AN were explored using isotherms and kinetic models. The thermodynamic parameters were calculated to determine the spontaneity and thermal nature of the MG adsorption reaction. The maximum equilibrium adsorption capacity of AN was found to be 113.26 mg/g at 30 °C. The MG adsorption data revealed that AN adsorbs MG by multilayer adsorption, as shown by the better fit of the data to the Freundlich and Halsey models (R2 = 0.99) rather than to the Langmuir model. Multilayer adsorption involves physisorption, which was confirmed by the E value (mean free energy of adsorption) of the Dubinin-Radushkevich model (6.52 kJ/mol). Surface diffusion was found to be the main driving force for MG adsorption by AN. The MG adsorption reaction was endothermic, based on the enthalpy, and was controlled by the entropy of the system in the T1 temperature range (30 to 40 °C), while the opposite trend was observed in the T2 range (40 to 50 °C). Moreover, MG adsorption by AN was found to be nonspontaneous at all temperatures.


Assuntos
Acacia/química , Resíduos Industriais , Corantes de Rosanilina/química , Adsorção , Difusão , Concentração de Íons de Hidrogênio , Cinética , Temperatura , Termodinâmica , Eliminação de Resíduos Líquidos/métodos
12.
Eur Cell Mater ; 30: 282-302, 2015 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-26614483

RESUMO

In situ tissue regeneration holds great promise for regenerative medicine and tissue engineering applications. However, to achieve control over long-term and localised presence of biomolecules, certain barriers must be overcome. The aim of this study was to develop electrospun scaffolds for the fabrication of artificial vascular grafts that can be remodelled within a host by endogenous cell recruitment. We fabricated scaffolds by mixing appropriate proportions of linear poly (l-lactide-co-ε-caprolactone) (PLCL) and substance P (SP)-immobilised PLCL, using electrospinning to develop vascular grafts. Substance P was released in a sustained fashion from electrospun membranes for up to 30 d, as revealed by enzyme-linked immunosorbent assay. Immobilised SP remained bioactive and recruited human bone marrow-derived mesenchymal stem cells (hMSCs) in an in vitro Trans-well migration assay. The biocompatibility and biological performance of the scaffolds were evaluated by in vivo experiments involving subcutaneous scaffold implantations in Sprague-Dawley rats for up to 28 d followed by histological and immunohistochemical studies. Histological analysis revealed a greater extent of accumulative host cell infiltration and collagen deposition in scaffolds containing higher contents of SP than observed in the control group at both time points. We also observed the presence of a large number of laminin-positive blood vessels and Von Willebrand factor (vWF+) cells in the explants containing SP. Additionally, scaffolds containing SP showed the existence of CD90+ and CD105+ MSCs. Collectively, these findings suggest that the methodology presented here may have broad applications in regenerative medicine, and the novel scaffolding materials can be used for in situ tissue regeneration of soft tissues.


Assuntos
Regeneração/efeitos dos fármacos , Células-Tronco/citologia , Substância P/farmacologia , Engenharia Tecidual , Indutores da Angiogênese/farmacologia , Animais , Materiais Biocompatíveis/química , Células Cultivadas , Teste de Materiais/métodos , Poliésteres/química , Ratos Sprague-Dawley , Regeneração/fisiologia , Engenharia Tecidual/métodos , Alicerces Teciduais
13.
J Big Data ; 11(1): 25, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38321999

RESUMO

The transformer model is a famous natural language processing model proposed by Google in 2017. Now, with the extensive development of deep learning, many natural language processing tasks can be solved by deep learning methods. After the BERT model was proposed, many pre-trained models such as the XLNet model, the RoBERTa model, and the ALBERT model were also proposed in the research community. These models perform very well in various natural language processing tasks. In this paper, we describe and compare these well-known models. In addition, we also apply several types of existing and well-known models which are the BERT model, the XLNet model, the RoBERTa model, the GPT2 model, and the ALBERT model to different existing and well-known natural language processing tasks, and analyze each model based on their performance. There are a few papers that comprehensively compare various transformer models. In our paper, we use six types of well-known tasks, such as sentiment analysis, question answering, text generation, text summarization, name entity recognition, and topic modeling tasks to compare the performance of various transformer models. In addition, using the existing models, we also propose ensemble learning models for the different natural language processing tasks. The results show that our ensemble learning models  perform better than a single classifier on specific tasks.

14.
Auton Neurosci ; 252: 103160, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38428323

RESUMO

There is still much uncertainty surrounding the approach to diagnosing and managing a sport-related concussion (SRC). Neurobiological recovery may extend beyond clinical recovery following SRC, highlighting the need for objective physiological parameters to guide diagnosis and management. With an increased understanding of the connection between the heart and the brain, the utility of assessing cardiovascular functioning following SRC has gained attention. As such, this review focuses on the assessment of cardiovascular parameters in the context of SRC. Although conflicting results have been reported, decreased heart rate variability, blood pressure variability, and systolic (ejection) time, in addition to increased spontaneous baroreflex sensitivity and magnitude of atrial contraction have been shown in acute SRC. We propose that these findings result from the neurometabolic cascade triggered by a concussion and represent alterations in myocardial calcium handling, autonomic dysfunction, and an exaggerated compensatory response that attempts to maintain homeostasis following a SRC. Assessment of the cardiovascular system has the potential to assist in diagnosing and managing SRC, contributing to a more comprehensive and multimodal assessment strategy.


Assuntos
Concussão Encefálica , Humanos , Concussão Encefálica/diagnóstico , Pressão Sanguínea , Encéfalo , Barorreflexo , Átrios do Coração
15.
Nature ; 447(7143): 487-92, 2007 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-17495930

RESUMO

Reactive oxygen species trigger cellular responses by activation of stress-responsive mitogen-activated protein kinase (MAPK) signalling pathways. Reversal of MAPK activation requires the transcriptional induction of specialized cysteine-based phosphatases that mediate MAPK dephosphorylation. Paradoxically, oxidative stresses generally inactivate cysteine-based phosphatases by thiol modification and thus could lead to sustained or uncontrolled MAPK activation. Here we describe how the stress-inducible MAPK phosphatase, Sdp1, presents an unusual solution to this apparent paradox by acquiring enhanced catalytic activity under oxidative conditions. Structural and biochemical evidence reveals that Sdp1 employs an intramolecular disulphide bridge and an invariant histidine side chain to selectively recognize a tyrosine-phosphorylated MAPK substrate. Optimal activity critically requires the disulphide bridge, and thus, to the best of our knowledge, Sdp1 is the first example of a cysteine-dependent phosphatase that couples oxidative stress with substrate recognition. We show that Sdp1, and its paralogue Msg5, have similar properties and belong to a new group of phosphatases unique to yeast and fungal taxa.


Assuntos
Fungos/enzimologia , Proteínas Tirosina Fosfatases/classificação , Proteínas Tirosina Fosfatases/metabolismo , Sequência de Aminoácidos , Sítios de Ligação , Catálise , Cisteína/metabolismo , Dissulfetos/metabolismo , Fosfatases de Especificidade Dupla , Histidina/metabolismo , Humanos , Modelos Moleculares , Dados de Sequência Molecular , Oxirredução/efeitos dos fármacos , Estresse Oxidativo , Fosfoproteínas Fosfatases/química , Fosfoproteínas Fosfatases/classificação , Fosfoproteínas Fosfatases/metabolismo , Fosfotirosina/metabolismo , Proteínas Tirosina Fosfatases/química , Proteínas de Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/classificação , Proteínas de Saccharomyces cerevisiae/metabolismo , Especificidade por Substrato
16.
J Clin Med ; 12(12)2023 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-37373610

RESUMO

Heart rate variability (HRV), systolic blood pressure variability (BPV), and spontaneous baroreflex sensitivity (BRS) are indirect and approximate measures of autonomic regulation of the cardiovascular system. Studies have shown differences in HRV and BRS between males and females; however, no study has observed differences in BPV, HRV, or BRS between male and female athletes. One hundred males (age 21.2 ± 2.1 y; BMI 27.4 ± 4.5 kg/m2) and sixty-five females (age: 19.7 ± 1.6 y; BMI 22.7 ± 2.2 kg/m2) were assessed during the pre-season baseline. We collected resting beat-to-beat blood pressure and R-R intervals using finger photoplethysmography and a 3-lead electrocardiogram, respectively. Participants underwent a controlled slow breathing protocol (six breaths/minute: 5 s inhale, 5 s exhale) for 5 min. Spectral and linear analysis was conducted on blood pressure and ECG data. Regression curves were fitted to the blood pressure and R-R signals, with the slopes providing the BRS parameters. Male athletes had significantly (p < 0.05) lower mean heart rate, RR interval SD2/SD1, HRV % low-frequency, and higher BP high-frequency power during controlled respiration. No differences were found in any BRS parameters. HRV and BPV responses to a slow breathing protocol differed between male and female athletes; however, BRS responses did not.

17.
Afr Health Sci ; 23(3): 576-583, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38357116

RESUMO

Background: Fiberoptic intubation (FOI) is considered a beneficial modality used to intubate life-threatening airway patients. This study aims at assessing the effectiveness of shortened uncuffed endotracheal tube as a nasopharyngeal airway during FOI. Methods: Between January 2019 and March 2021, this prospective randomized controlled trial has enrolled 62 adult patients (56 males and 6 females) with normal airways scheduled for elective oral FOI classified American Society of Anesthesiologists (ASA I-III), their age ranged 20-60 years. The patients were randomized into two equal groups (31 per each); in group I, FOI was carried using lingual traction, and in group II, FOI was carried out with lingual traction plus a shortened uncuffed endotracheal tube as a modified nasopharyngeal airway to maintain oxygenation. The time taken to successful tracheal intubation and other technical parameters have been measured. The heart rate (HR), mean arterial pressure (MAP), oxygen saturation (SpO2), end-tidal carbon dioxide (EtCO2), and any associated complications have been measured. Results: During insertion of the scope, the SpO2 was significantly decreased in group I (92.55 ± 7.94) compared to group II (97.42 ± 6.34), p=0.009. The heart rate, MAP, and EtCO2 were found to be insignificantly different in both groups (p>0.05). The time needed for intubation in group I (2.78±0.98 min) was prolonged compared with group II (1.95±1.02 min) p =0.002. The number of attempts was comparable in both groups, while the number of successful intubations from the 1st attempt was 12 (39%) compared to 18 (58%) in groups I and II respectively, p=0.36. The overall success rate by juniors was 71% in group I compared to 84% in group II, p=0.66 with a lower incidence of using rescue oxygen and other facilitating maneuvers. Conclusions: The modified nasopharyngeal airway is a useful modality to facilitate oral FOI by anesthesia resident trainees.


Assuntos
Anestesia , Intubação Intratraqueal , Masculino , Adulto , Feminino , Humanos , Adulto Jovem , Pessoa de Meia-Idade , Estudos Prospectivos , Frequência Cardíaca
18.
Braz J Biol ; 84: e260922, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35894353

RESUMO

Alphasatellites (family Alphasatellitidae) are circular, single-stranded (ss) DNA molecules of ~1350 nucleotide in size that have been characterized in both the Old and New Worlds. Alphasatellites have inherent ability to self-replicate, which is accomplished by a single protein, replication-associated protein (Rep). Although the precise function of alphasatellite is yet unknown, and these consider dispensable for infectivity, however, their Rep protein functions as a suppressor of host defence. While alphasatellites are most frequently associated with begomoviruses, particularly with monopartite than bipartite begomoviruses, they have recently been found associated with mastreviruses. The in planta maintenance of alphasatellites by helper geminivirus is still an enigma, with no available study on the topic. This study aimed to investigate whether a widely distributed bipartite begomovirus, tomato leaf curl New Delhi virus (ToLCNDV), can maintain cotton leaf curl Multan alphasatellite (CLCuMuA) in the presence or absence of cotton leaf curl Multan betasatellite (CLCuMuB). The findings of this study demonstrated that ToLCNDV or its DNA A could maintain CLCuMuA in Nicotiana benthamiana plants. However, the presence of CLCuMuB interferes with the maintenance of CLCuMuA, and mutations in the CP of ToLCNDV further reduces it. Our study highlighted that the maintenance of alphasatellites is impaired in the presence of a betasatellite by ToLCNDV. Further investigation is needed to unravel all the interactions between a helper virus and an alphasatellites.


Assuntos
Begomovirus , Solanum lycopersicum , Begomovirus/genética , DNA Satélite/genética , DNA Viral/genética , Filogenia , Doenças das Plantas
19.
PLoS One ; 17(3): e0265024, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35239747

RESUMO

The application of layered double hydroxides (LDHs) of MgFe and its composites with biochar of Eucalyptus camdulensis (Eb) and ethylenediaminetetraacetic acid (EDTA) was explored in a batch study to mitigate toxic lead ions (Pb2+) from synthetic wastewater solutions. SEM images revealed that MgFe/LDH composites with Eb were successfully formed, while FTIR spectra confirmed the successful adsorption of Pb2+ onto the MgFe/LDH and composite adsorbents. Batch equilibrium was attained after 60 min, then the adsorption capacity gradually increased. An increase in adsorption capacity (and a 60% decrease in the percentage removal) was observed by increasing the initial Pb2+ concentration, and the highest value was 136 mg g-1 for MgFe/LDH-Eb_EDTA. A 50-60% increase in both the adsorption capacities and percent removal was seen in the pH range of 2-6. The second-order kinetic model had a nearly perfect fitting, suggesting that chemisorption was the mechanism controlling adsorption. The Langmuir isotherm model best presented the adsorption data, suggesting that the Pb2+ adsorption was monolayer, and predicted a better affinity between the adsorbent surface and absorbed Pb2+ for MgFe/LDH-Eb_EDTA in comparison to the other two adsorbents. The D-R isotherm suggested that the adsorption system was physical based on E values for all three adsorbents, while the Temkin isotherm model suggested that Pb2+ adsorption was heterogeneous. Finally, the Sips and R-P isotherms predicted that the adsorption of Pb2+ on the surface of the adsorbents was homogeneous and heterogeneous.


Assuntos
Chumbo , Poluentes Químicos da Água , Adsorção , Carvão Vegetal , Ácido Edético , Hidróxidos , Cinética , Água , Poluentes Químicos da Água/análise
20.
Poult Sci ; 101(3): 101667, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35131639

RESUMO

The present study was conducted to assess the growth performance, morphometric traits, muscle chemical composition and cholesterol content in four phenotypes of naked neck chicken (black, white-black, light brown and dark brown). A total of 320-day-old chicks, 80 from each phenotype, were randomly stratified into 20 replicates (16/replicate), according to a completely randomized design. The results showed higher final body weight, weight gain, and better FCR in both light brown and dark brown phenotypes whereas time of gains was found to be greater in dark brown phenotype. Keel length and shank circumference were greater in dark brown whereas wing spread was found to be higher in light brown phenotype. Drumstick circumference and body length did not show any significant differences (P > 0.05) across the phenotypes. Dry matter was found to be higher in white black, crude protein in black, white black and dark brown, moisture in light brown, and cholesterol content in black whereas ether extract and ash content were found to be greater in black and white black phenotypes. In conclusion, both light brown and dark brown phenotypes showed superior growth performance and morphometric traits. Similarly, from a health point of view, the dark brown and light brown phenotypes seem superior because their cholesterol content was low. Thus, it is strongly recommended that there should be a conscious effort to improve economically important traits of the light and dark brown birds to be used as dual-purpose slow growing chicken, especially in developing countries.


Assuntos
Galinhas , Carne , Animais , Galinhas/fisiologia , Colesterol , Carne/análise , Fenótipo , Aumento de Peso
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