Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 1.198
Filtrar
1.
J Sci Food Agric ; 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38873999

RESUMO

BACKGROUND: Insufficient endogenous nutrients in the broiler embryo can lead to muscle gluconeogenesis, which ultimately affects the post-hatching performance of chicks. This study investigated the effects of in ovo feeding (IOF) of N-carbamylglutamate (NCG) on the growth hormones, carcass yield, and meat quality in broilers. Fertile eggs from a 30-week-old Ross 308 breeder flock were divided into three treatment groups: NC (non-injection), SC (100 µL saline-injection), and NCG (2 mg NCG injection). Each group had six replicates, with 70 eggs per replicate during incubation. Injections were administered on the 17.5th day of embryonic development. After hatching, 270 chicks were selected for 42-day rearing for further sampling. RESULTS: Chicks in the NCG group had significantly higher body weight (BW) and average daily gain (ADG) at the growing phase, increased growth and testosterone hormone in both feeding phases (21 and 42 days), and improved average daily gain (ADG) and food conversion ratio (FCR) in both grower and entire feeding phases (P < 0.05). Triiodothyronine (T3) and tetraiodothyronine (T4) levels, carcass yield, dressing, drum weight, breast muscle weight, drumstick weights, thighs, pectoralis major, and their part percentage of carcass were improved in the NCG group (P < 0.05), these effects were varied along feeding phases. Moreover, IOF of the NCG also improved pectoralis breast muscle color values at 24 h post mortem (P < 0.05). CONCLUSION: These results suggest that NCG injection at the late embryonic age of broiler enhances growth performance and meat quality throughout the lifespan and this can probably be attributed to an increase in thyroid and testosterone hormones, indicating potential involvement in metabolic and nutrient partitioning pathway regulation. © 2024 Society of Chemical Industry.

2.
Eur J Clin Microbiol Infect Dis ; 41(6): 907-911, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35524829

RESUMO

Oral fluid specimens (OF) have been widely used to know the HIV prevalence in several key populations. Here, we aim to validate in OF specimens an existing HIV chemiluminiscence assay for serum specimens. Paired OF and serum specimens were collected from 83 known HIV-positives and 83 known HIV-negatives in order to validate the performance characteristics of the automated chemiluminiscence Liaison XL Murex HIV Ag/Ab assay (Diasorin Inc, Iberia) for HIV antibody detection in OF specimens. Among the previously known HIV-seropositive group, HIV antibodies were detected in 69 out of 83 OF specimens. All serum and OF specimens collected from 83 HIV seronegative individuals were negative. The sensitivity and specificity of this assay were 83.13% and 100% respectively in OF. The PPV and NPV values were 100% and 85.57% respectively. The correlation obtained between both specimens was (K: 0.83, [95% CI: 0.748-0.915]) according to the kappa index. The ROC curve analysing the optimal cut-off of the Liaison XL Murex HIV Ag/Ab to detect positive OF specimens revealed that a cut-off of 0.497 showed sensitivity and specificity values of 98.8% and 97.59% respectively. Taking into account this cut-off, the overall sensitivity and NPV of the Liaison XL Murex HIV Ag/Ab assay could rise from 83.1 to 98.8% and from 85.5 to 97.7%, respectively. Our results suggest that the Liaison XL HIV Ag/Ab assay is suitable for the detection of HIV antibodies in OF specimens.


Assuntos
Infecções por HIV , HIV-1 , Anticorpos Anti-HIV , Infecções por HIV/diagnóstico , Humanos , Sensibilidade e Especificidade
3.
Opt Express ; 29(21): 34293-34301, 2021 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-34809223

RESUMO

Systems of controllable orbital angular momentum (OAM) require more compact, higher conversion efficiency and more tolerable wavelength or polarization. We introduce an optical vortex switch based on a multiplexed volume grating (MVG). The MVG recorded in a piece of photo-thermo-refractive (PTR) glass exhibits high diffraction efficiency (DE, also known as conversion efficiency in transporting), sensitive angular selectivity, and polarization-insensitivity. The effects of the incident divergence angle and polarization on the DE and the far-field diffraction profiles are demonstrated and investigated. It turns out that the divergence angle of the probe beam can greatly affect the DE. The fluctuation of the DE caused by polarization variation is less than 1.59%. This switch can be potentially applied in vortex tweezers, optical communication, and high power systems.

4.
J Magn Reson Imaging ; 50(6): 1731-1741, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31095830

RESUMO

BACKGROUND: Tinnitus is considered to be triggered by aberrant neural activity in the brain. Sound therapy is regarded as a reasonable management option for tinnitus treatment and has been applied in the clinical setting for decades. HYPOTHESIS: We hypothesized that sound therapy, a commonly used tinnitus treatment method, would alter the functional connectivity (FC) of brain regions in tinnitus models. STUDY TYPE: Longitudinal. POPULATION: Resting-state functional MRI data were collected from 27 tinnitus patients before and after 12 weeks of sound therapy. Twenty-seven age- and sex-matched healthy controls were also longitudinally scanned at the 12-week timepoint. FIELD STRENGTH: 3.0T MRI system and echo planar imaging (EPI) sequence, 3D brain volume imaging (BRAVO) sequence. ASSESSMENT: Functional connectivity strength (FCS), a graph-theoretical-based analytic method, was applied to analyze the FC features in the whole brain. STATISTICAL TESTS: Student's t-test and chi-square test were used for analyses between two groups. A two-way analysis of covariance (ANCOVA) followed by post-hoc analyses was performed to determine differences of FC. RESULTS: The interaction effect between the two groups and two scans on FCS was observed in the bilateral thalami and left anterior cingulate cortex (ACC). The fitted FCS values in the bilateral thalami were significantly higher in tinnitus patients at baseline and decreased to a relatively normal range after sound therapy compared with healthy controls. Conversely, the fitted FCS values in the left ACC were within the normal range, but increased after treatment (1.08 ± 0.29, P < 0.02); however, there was no change in the control group. Importantly, significant correlations were observed between the FCS changes in the right thalamus (P = 0.028), the FC of the right thalamus-right inferior frontal gyrus (P = 0.015), and symptomatic improvement. DATA CONCLUSION: Sound therapy may modulate the brain network by altering the gating function of the thalamus as well as enhancing the tinnitus-canceling system. LEVEL OF EVIDENCE: 2 Technical Efficacy Stage: 4 J. Magn. Reson. Imaging 2019;50:1731-1741.


Assuntos
Estimulação Acústica/métodos , Mapeamento Encefálico/métodos , Encéfalo/fisiopatologia , Imageamento por Ressonância Magnética/métodos , Zumbido/fisiopatologia , Zumbido/terapia , Adolescente , Adulto , Idoso , Imagem Ecoplanar/métodos , Feminino , Humanos , Imageamento Tridimensional/métodos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Vias Neurais/fisiopatologia , Descanso , Adulto Jovem
5.
Ecotoxicol Environ Saf ; 166: 165-175, 2018 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-30267989

RESUMO

This study was conducted to investigate the ameliorative effect of selenium on microcystin-LR induced toxicity in bovine Sertoli cells. Bovine Sertoli cells were pretreated with selenium (Na2SeO3) for 24 h after which selenium pretreated and non-pretreated Sertoli cells were cultured in medium containing 10% heat activated fetal bovine serum FBS+ 80 µg/L MC-LR to assess its ameliorative effect on MC-LR toxicity. The results show that selenium pretreatment inhibited the MC-LR induced mitophagy, downregulation and mislocalization of blood-testis barrier constituent proteins in bovine Sertoli cells via NF-kB and cytochrome c release blockage. The observed downregulation of electron transport chain (ETC) related genes (mt-ND2, COX-1, COX-2) and upregulation of inflammatory cytokines (IL-6, TNF-α, IL-1ß, IFN-γ, IL-4, IL-10, 1 L-13, TGFß1) in non-pretreated cells exposed to MC-LR were ameliorated in selenium pretreated cells. There was no significant difference (P > 0.05) in the protein levels of blood-testis barrier constituent proteins (ZO-1, occludin, connexin-43, CTNNB1, N-cadherin) and mitochondria related genes (mt-ND2, COX-1, COX-2, ACAT1, mtTFA) of selenium pretreated Sertoli cell compared to the control. Taken together, we conclude that selenium inhibits MC-LR caused Mitophagy, downregulation and mislocalization of blood-testis barrier proteins of bovine Sertoli cell via mitochondrial and TLR4/NF-kB signaling pathways blockage.


Assuntos
Microcistinas/toxicidade , Mitocôndrias/efeitos dos fármacos , Células de Sertoli/efeitos dos fármacos , Selenito de Sódio/farmacologia , Animais , Barreira Hematotesticular/efeitos dos fármacos , Bovinos , Citocinas/metabolismo , Regulação para Baixo , Masculino , Toxinas Marinhas , Mitocôndrias/metabolismo , Mitofagia/efeitos dos fármacos , NF-kappa B/antagonistas & inibidores , Células de Sertoli/metabolismo , Transdução de Sinais/efeitos dos fármacos , Receptor 4 Toll-Like/antagonistas & inibidores
6.
Zhong Yao Cai ; 39(7): 1605-9, 2016 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-30204363

RESUMO

Objective: To prepare the salviae miltiorrhiza and ligustrazine hydrochloride nasal thermosensitive in situ gel and to study the characterization of its nasal mucosal permeability. Methods: With gelling temperature as the dependent variable, the contents of poloxamer 407( P407), poloxamer 188( P188) and PEG-6000 as independent variables. The best prescription was optimized by central composite design-response surface methodology. The release in vitro and the skin permeation ability were evaluated in Franz diffusion cell. Results: The optimal formulation composed with the dosage of P407,P188 and PEG-6000 were 18%,7% and 1%,respectively. The cumulative release in vitro was over 70% after 12 h, and the release curve conformed to the first-order kinetic equation. The cumulative permeation of salviae miltiorrhiza and ligustrazine hydrochloride in the gel were 2 649. 77 µg / cm2 and 119. 72 µg / cm2 after 12h. Conclusion: The central composite design-response surface methodolog was stable and feasible for preparation of nasal thermosensitive in situ gel of salviae miltiorrhiza and ligustrazine hydrochloride, the drug-loaded gel has sustained release effect.


Assuntos
Mucosa Nasal , Animais , Géis , Permeabilidade , Poloxâmero , Pirazinas , Temperatura
7.
Neurochem Res ; 40(3): 428-37, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25567480

RESUMO

α-Synuclein (α-Syn) plays a crucial role in the pathophysiology of Parkinson's disease (PD), the degeneration of dopaminergic neurons. Previous studies have shown that α-Syn regulates dopamine synthesis by binding to and inhibiting tyrosine hydroxylase (TH). In neurons, protein phosphatases (PPs) play a prominent role in directing signaling toward survival or degeneration. This study was to re-evaluate whether α-Syn could regulate the tyrosine hydroxylase phosphorylation by protein phosphatase-2A (PP2A) in dopaminergic MN9D cells and cortex neurons. Our data demonstrated for the first time that α-Syn stimulates PP2A activity and reduces phosphorylation of TH through regulating the methylation of PP2A in dopaminergic MN9D cells and primary cortex neurons. Increased PP2A activity and reduced phosphorylation of PP2A at Y307 (inactive form of PP2A) were observed in α-Syn overexpression dopaminergic cells (Syn) and primary cortex neurons, and the TH phosphorylation relieved by enhancing PP2A methylation in Syn group could be abated by using PP inhibitors, okadaic acid (OKA). OKA could reduce the cell damage and cell apoptosis induced by α-Syn. Thus our findings may provide an insight into the complicated pathogenesis of PD as well as some clues to the development of novel therapeutic strategies targeting at PP2A.


Assuntos
Proteína Fosfatase 2/metabolismo , Tirosina 3-Mono-Oxigenase/metabolismo , alfa-Sinucleína/farmacologia , Animais , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Células Cultivadas , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Fosforilação/efeitos dos fármacos , Fosforilação/fisiologia , alfa-Sinucleína/biossíntese
8.
Zhonghua Jie He He Hu Xi Za Zhi ; 38(3): 170-3, 2015 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-26269303

RESUMO

OBJECTIVE: To explore the value of autofluorescence bronchoscopy in guiding surgical resection range for central lung cancer. METHODS: A total of 213 patients with lung cancer were evaluated by both light bronchoscopy (WLB) and autofluorescence bronchoscopy (AFB) by BF-F260 (Olympus, Japan) before surgery from Mar. 2012 to Feb. 2013. The number of positive cases under each mode, clinical stage, surgical resection range and surgical options were evaluated to explore diagnostic value of WLB and AFB. RESULTS: Of the 213 cases, surgical margins were negative in 198 cases, while the remaining 15 cases were found to be inoperable. A total of 1 146 biopsies from different sites including neoplasm and bronchial mucosa were evaluated for tumor involvement by pathology. On average, biopsy was performed 5.0 ± 1.2 times for each patient. The sensitivity of the WLB group and the AFB group was 65. 2% (214/662) and 81.2% (237/484), and the specificity was 74.8% (214/662) and 54.7% (237/484), respectively, the difference being statistically significant (χ2 = 19.747, P < 0.05). Bronchial mucosal invasion was found by fluorescence bronchoscopy and the surgical procedures were changed in 27 case: from lobectomy to bilobectomy and pneumonectomy in 10, from lobectomy to inoperable in 2, from lobectomy to interlobar ridge plasty( sleeve resection) in 8, from pneumonectomy to inoperable in 3, and from pneumonectomy to carina plasty in 4 cases. In all the 213 patients, 214 pathological positive sites were found in the WLB group and 237 in the AFB group. The difference being statistically significant (χ2 = 32.439, P < 0.05). CONCLUSION: Autofluorescence bronchoscopy showed a high sensitivity for lung cancer, and was helpful to guide surgical resection range and reduce postoperative recurrence rate.


Assuntos
Broncoscopia/métodos , Neoplasias Pulmonares/cirurgia , Cirurgia Assistida por Computador/métodos , Biópsia , Fluorescência , Humanos , Recidiva Local de Neoplasia , Pneumonectomia , Sensibilidade e Especificidade
9.
Bioinspir Biomim ; 19(2)2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38316027

RESUMO

The flying bat can detect the difference in Doppler frequency between its echolocation transmission signal and the echoes in its surroundings, enabling it to distinguish between various scenarios effectively. By examining the bio-sonar biomimetic model of a flying bat that uses echo Doppler information for environmental recognition, it may enhance the scene recognition capability of human ultrasound sonar during movement. The paper establishes a three-dimensional clutter model of the flying state of bat bio-sonar for bats emitting constant frequency signals. It proposes a scene recognition method that combines multi-scale time-frequency feature analysis with a convolutional neural network (CNN). The short-time Fourier transform of different scales extract the Doppler and range dimensions, which are then fused to create a multi-scale feature plane containing both Doppler and range information. Combined with CNN's powerful image classification and recognition capabilities, extract features from multi-scale feature planes of different clutter scenes to achieve environment recognition based on the differences in Doppler and range dimensions of echoes in various directions. Through computer simulations, this study provides a numerical interpretation of the environmental classification and perception capabilities of bats in flight. The algorithm significantly improves scenario classification and recognition performance according to simulation results, with accuracy exceeding 98% in varied clutter scenarios at 30 dB signal noise ratio. Based on computer simulations, an experimental scene was constructed and actual echo signals were collected and analyzed. The experiments demonstrate that utilizing Doppler information enables the classification and recognition of cluttered environments. The effectiveness of the proposed algorithm was also verified. Ultrasonic sonar systems, such as navigation robots and helicopter obstacle avoidance, can apply this biomimetic model and algorithm for environmental recognition during motion.


Assuntos
Quirópteros , Ecolocação , Animais , Biomimética , Som
10.
Physiol Meas ; 45(1)2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38086063

RESUMO

Objective. Understanding a patient's respiratory effort and mechanics is essential for the provision of individualized care during mechanical ventilation. However, measurement of transpulmonary pressure (the difference between airway and pleural pressures) is not easily performed in practice. While airway pressures are available on most mechanical ventilators, pleural pressures are measured indirectly by an esophageal balloon catheter. In many cases, esophageal pressure readings take other phenomena into account and are not a reliable measure of pleural pressure.Approach.A system identification approach was applied to provide accurate pleural measures from esophageal pressure readings. First, we used a closed pressurized chamber to stimulate an esophageal balloon and model its dynamics. Second, we created a simplified version of an artificial lung and tried the model with different ventilation configurations. For validation, data from 11 patients (five male and six female) were used to estimate respiratory effort profile and patient mechanics.Main results.After correcting the dynamic response of the balloon catheter, the estimates of resistance and compliance and the corresponding respiratory effort waveform were improved when compared with the adjusted quantities in the test bench. The performance of the estimated model was evaluated using the respiratory pause/occlusion maneuver, demonstrating improved agreement between the airway and esophageal pressure waveforms when using the normalized mean squared error metric. Using the corrected muscle pressure waveform, we detected start and peak times 130 ± 50 ms earlier and a peak amplitude 2.04 ± 1.46 cmH2O higher than the corresponding estimates from esophageal catheter readings.Significance.Compensating the acquired measurements with system identification techniques makes the readings more accurate, possibly better portraying the patient's situation for individualization of ventilation therapy.


Assuntos
Respiração Artificial , Mecânica Respiratória , Humanos , Masculino , Feminino , Pressão , Mecânica Respiratória/fisiologia , Respiração Artificial/métodos , Pulmão , Catéteres
11.
Chem Commun (Camb) ; 60(45): 5856-5859, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38752695

RESUMO

The membrane emulsification technique enables the self-assembly of cellulose nanocrystals (CNCs) confined within a spherical geometry for large-scale production. The resulting solid microspheres show long-range ordering with chiral nematic structures, and this fascinating hierarchical architecture can even be transferred to mesoporous carbon or silica microparticles by a sacrificial template method.

12.
Explore (NY) ; 19(5): 718-720, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36806384

RESUMO

The incidence of diabetes mellitus is increasing rapidly, and this condition often results in severe complications. One such complication, diabetic oculomotor nerve palsy (ONP), that can lead to significant impairment of visual function is increasingly recognized. However, there are few reports in the literature on the treatment of diabetic ONP. In the present case, the use of needling a selection of local and distal acupoints showed promising results for the treatment of diabetic ONP. We also present a brief literature review related to this case.


Assuntos
Terapia por Acupuntura , Acupuntura , Diabetes Mellitus , Doenças do Nervo Oculomotor , Doenças Vasculares , Humanos , Pontos de Acupuntura , Diabetes Mellitus/terapia , Doenças do Nervo Oculomotor/etiologia , Doenças do Nervo Oculomotor/terapia , Resultado do Tratamento
13.
Mol Cytogenet ; 16(1): 23, 2023 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-37667392

RESUMO

BACKGROUND: Small supernumerary marker chromosome (sSMC) is a structurally abnormal chromosome of unknown origin by conventional cytogenetics. The understanding of clinical significance of sSMC is still limited in prenatal diagnosis. The presence of sSMC poses a challenge for genetic counselling. METHODS: We obtained the clinical information of 25 cases with sSMC. The fetal samples were subjected to multiple molecular and cytogenetic approaches including karyotype analysis, chromosomal microarray analysis, bacterial artificial chromosomes-on-beads assay, and fluorescence in situ hybridization. RESULTS: Seven sSMCs were found to be r(X), and five of the cases terminated the pregnancy. Three markers were idic(15), and one of the cases was normal at birth. Two markers were i(12p), and both cases terminated the pregnancy. Other markers were r(Y) (outcome: normal at birth), i(18p) (outcome: stillbirth), der(15) (outcome: terminated), del(9) (outcome: terminated), dup(13) (outcome: follow-up loss), and derived from chromosome 21 (outcome: stillbirth). Seven markers were of unknown origin because not all methods were applied to them. CONCLUSION: Applying multiple molecular and cytogenetic approaches could identify the origin and genetic content of sSMC to assist the genetic counselling in prenatal diagnosis.

14.
Psychon Bull Rev ; 2023 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-37884777

RESUMO

One of the first tasks in language acquisition is word segmentation, a process to extract word forms from continuous speech streams. Statistical approaches to word segmentation have been shown to be a powerful mechanism, in which word boundaries are inferred from sequence statistics. This approach requires the learner to represent the frequency of units from syllable sequences, though accounts differ on how much statistical exposure is required. In this study, we examined the computational limit with which words can be extracted from continuous sequences. First, we discussed why two occurrences of a word in a continuous sequence is the computational lower limit for this word to be statistically defined. Next, we created short syllable sequences that contained certain words either two or four times. Learners were presented with these syllable sequences one at a time, immediately followed by a test of the novel words from these sequences. We found that, with the computationally minimal amount of two exposures, words were successfully segmented from continuous sequences. Moreover, longer syllable sequences providing four exposures to words generated more robust learning results. The implications of these results are discussed in terms of how learners segment and store the word candidates from continuous sequences.

15.
Sci Rep ; 13(1): 2492, 2023 02 13.
Artigo em Inglês | MEDLINE | ID: mdl-36781913

RESUMO

Thinning is an important silvicultural practice for improving the productivity and wood production in plantation forest. Different intensities of thinning management can affect tree growth and alter soil nutrient effectiveness, thus affecting soil fungal community structure and diversity. Our objective is to determine the soil factors and their regulatory mechanisms that influence stand growth by thinning, and to provide data to support the establishment of large diameter timber cultivation technology for Picea koraiensis. In this study, we conducted medium- and high-intensity thinning in 43a P. koraiensis plantation middle-aged forests and investigated the growth indexes, soil physicochemical properties, and fungal community diversity in rhizosphere and non-rhizosphere soils of the stands after thinning at different densities (904 plants/ha for control, 644 plants/ha for 30% thinning intensity, and 477 plants/ha for 50% thinning intensity). The results showed that all growth indicators (annual growth of tree height, diameter at breast height, height under live branches and crown width) of the plantation after high-intensity thinning (477 plants/ha) were higher than those of the control (no thinning, significant) and medium-intensity thinning (644 plants/ha). Mycorrhizal infection rate was higher at the beginning of the growing season than at the end of the growing season, and increased slightly with decreasing stand density. Compared to the control, all medium- and high-intensity thinning treatments significantly improved soil nutrient content (P < 0.05), including total carbon, total nitrogen, total phosphorus, total potassium, Available phosphorus and Available potassium. Fungal diversity was higher but lower in abundance than the control in both rhizosphere and non-rhizosphere soils after thinning. The number of OTUs and fungal richness and diversity indices of non-rhizosphere soil fungi were higher than those of rhizosphere soil fungi. In conclusion, this study provides new evidence that reasonable intercalation can increase the radial and vertical growth of P. koraiensis plantation forests and promote the diversity of subsurface soil fungal communities. It is shown that thinning intensity regulates biogeochemical cycles in P. koraiensis plantation ecosystems by affecting soil nutrients and fungal community structure. Therefore, 50% thinning intensity can be used to increase timber production in plantation forests during large diameter timber cultivation of P. koraiensis and improve predictions associated with achieving long-term forest management strategies.


Assuntos
Micobioma , Picea , Ecossistema , Solo/química , Florestas , Árvores , Plantas , Fósforo , Nutrientes , Microbiologia do Solo , Potássio
16.
Front Physiol ; 14: 1269656, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38292448

RESUMO

Objective: While long-term dynamic breath-holding training has been extensively studied to enhance cardiopulmonary function in athletes, limited research has explored the impact of a single breath-holding session on subsequent athletic capacity. In addition, Dry Dynamic Apnea (DA) has a more immediate physiological response than wet and static breath-holding. This study aims to assess the immediate effects of a single session of DA on the aerobic power and hematological parameters of elite athletes. Methods: Seventeen elite male rugby athletes (average age 23.5 ± 1.8) participated in this study. Two warm-up protocols were employed prior to incremental exercise: a standard warm-up (10 min of no-load pedaling) and a DA warm-up (10 min of no-load pedaling accompanied by six maximum capacity breath holds, with 30 s between each breath hold). Fingertip blood indicators were measured before and after warm-up. The incremental exercise test assessed aerobic parameters with self-regulation applied throughout the study. Results: Compared to the baseline warm-up, the DA warm-up resulted in a significant increase in VO2peak from 3.14 to 3.38 L/min (7.64% change, p < 0.05). HRmax increased from 170 to 183 bpm (7.34% change, p < 0.05), and HRpeak increased from 169 to 182 bpm (7.52% change, p < 0.05). Hematocrit and hemoglobin showed differential changes between the two warm-up methods (PHematocrit = 0.674; Phemoglobin = 0.707). Conclusion: This study investigates how DA influences physiological factors such as spleen contraction, oxygen uptake, and sympathetic nerve activation compared to traditional warm-up methods. Immediate improvements in aerobic power suggest reduced vagus nerve stimulation, heightened sympathetic activity, and alterations in respiratory metabolism induced by the voluntarily hypoxia-triggered warm-up. Further research is warranted to comprehensively understand these physiological responses and optimize warm-up strategies for elite athletic performance.

17.
J Colloid Interface Sci ; 634: 110-120, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36535151

RESUMO

In order to realise high ionic conductivity and improved chemical stability, a series of anion exchange membranes (AEMs) with semi-interpenetrating polymer network (sIPN) has been prepared via the incorporation of crosslinked poly(biphenyl N-methylpiperidine) (PBP) and spirobisindane-based intrinsically microporous poly(ether ketone) (PEK-SBI). The formation of phase separated structures as a result of the incompatibility between the hydrophilic PBP network and the hydrophobic PEK-SBI segment, has successfully promoted the hydroxide ion conductivity of AEMs. A swelling ratio (SR) as low as 12.2 % at 80 °C was recorded for the sIPN containing hydrophobic PEK-SBI as the linear polymer and crosslinked structure with a mass ratio of PBP to PEK-SBI of 90/10 (sIPN-90/10(PEK-SBI)). The sIPN-90/10(PEK-SBI) AEM achieved the highest hydroxide ion conductivity of 122.4 mS cm-1 at 80 °C and a recorded ion exchange capacity (IEC) of 2.26 meq g-1. Atomic force microscopy (AFM) and transmission electron microscopy (TEM) clearly revealed the improved phase separation structure of sIPN-90/10(PEK-SBI). N2 adsorption isotherm indicated that the Brunauer-Emmett-Teller (BET) surface area of the AEMs increased with the increase of microporous PEK-SBI content. Interestingly, the sIPN-90/10(PEK-SBI) AEM showed good alkaline stability for being able to maintain a conductivity of 94.7 % despite being soaked in a 1 M sodium hydroxide solution at 80 °C for 30 days. Meanwhile, a peak power density of 481 mW cm-2 can be achieved by the hydrogen/oxygen single cell using sIPN-90/10(PEK-SBI) as the AEM.


Assuntos
Éter , Etil-Éteres , Éteres , Ânions , Cetonas
18.
Liver Int ; 32(1): 137-46, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22097972

RESUMO

BACKGROUND: Adefovir dipivoxil (ADV) is a nucleotide analogue with proven efficacy in chronic hepatitis B (CHB). AIMS: This study investigated long-term ADV treatment in HBeAg-positive patients. METHODS: A total of 480 Chinese subjects with HBeAg-positive CHB who participated in a 1-year, double-blind, placebo-controlled study of ADV 10 mg daily were offered open-label continuation for a further 208 weeks. RESULTS: A total of 390 subjects completed 5 years of treatment. Baseline median hepatitis B virus (HBV) DNA was 8.8 log(10) copies/ml and alanine aminotransferase (ALT) 2.6 × upper limit of normal. Treatment with ADV resulted in sustained suppression of median HBV DNA by 4.8, 5.0, 5.1, 5.4 and 5.5 log(10) copies/ml after 1, 2, 3, 4 and 5 years respectively. Continuous treatment with ADV led to a progressive increase in the proportion of subjects achieving undetectable HBV DNA, from 28% after 1 year to 58% after 5 years. HBeAg seroconversion rates increased cumulatively from 11% after 1 year to 29% after 5 years. HBsAg seroconversion was achieved by 1.0% of patients. ADV resulted in ALT normalization that was maintained throughout this study in 75-79% of subjects. Virological breakthrough associated with ADV resistant mutations (rtN236T and rtA181V) occurred in 14.6% of subjects. ADV was well tolerated. CONCLUSION: Five years of ADV treatment in Chinese subjects with HBeAg-positive CHB resulted in increasing virological and serological responses and sustained biochemical responses over time. Virological resistance was identified in 14.6% of patients. Urgent switch or add-on therapy with a nucleoside analogue is necessary if ADV resistant mutations are detected, particularly rtN236T. Treatment was well tolerated.


Assuntos
Adenina/análogos & derivados , Antivirais/uso terapêutico , Antígenos E da Hepatite B/sangue , Hepatite B Crônica/tratamento farmacológico , Organofosfonatos/uso terapêutico , Adenina/uso terapêutico , Adolescente , Adulto , Povo Asiático , DNA Viral/análise , Farmacorresistência Viral/genética , Feminino , Vírus da Hepatite B/genética , Vírus da Hepatite B/imunologia , Hepatite B Crônica/diagnóstico , Hepatite B Crônica/virologia , Humanos , Testes de Função Hepática , Masculino , Pessoa de Meia-Idade , Mutação/efeitos dos fármacos , Resultado do Tratamento , Carga Viral/efeitos dos fármacos , Viremia/tratamento farmacológico , Adulto Jovem
19.
Mol Cytogenet ; 15(1): 41, 2022 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-36127686

RESUMO

BACKGROUND: Complex chromosomal rearrangements (CCRs) are rare chromosomal structural variations, containing a variety of rearrangements such as translocation, inversion and/or insertion. With the development of cytogenetic and molecular genetic techniques, some chromosomal rearrangements that were initially considered to be simple reciprocal translocations in the past might eventually involve more complex chromosomal rearrangements. CASE PRESENTATION: In this case, a pregnant woman, who had a spontaneous abortion last year, had abnormal prenatal test results again in the second pregnancy. Applying a combination of genetic methods including karyotype analysis, chromosomal microarray analysis, fluorescence in situ hybridization and optical genome mapping confirmed that the pregnant woman was a carrier of a CCR involving three chromosomes and four breakpoints, and the CCR was paternal-origin. Her first and second pregnancy abnormalities were caused by chromosomal microdeletions and microduplications due to the malsegregations of the derivative chromosomes. CONCLUSIONS: We presented a rare familial CCR involving three chromosomes and four breakpoints. This study provided precise and detailed information for the subsequent reproductive decision-making and genetic counselling of the patient.

20.
Soc Indic Res ; 162(2): 501-524, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34866753

RESUMO

The determinants of health are influenced by genetics, lifestyle, social environment, medical conditions, etc. As an informal system, social capital plays an increasingly recognized role in individual health. The purpose of this paper is to discuss the direct and indirect effects of social capital on individual health in China. Using cross-sectional data from the China Family Panel Studies 2016, this paper explores the effects of cognitive and structural social capital on individual health from a micro perspective. The results show that both types of social capital have significant positive effects on individual health, and this effect remains after endogeneity is considered. The two types of social capital show obvious heterogeneity in age samples, urban and rural samples and north-south samples. In addition, the mechanism analysis shows that the health promotion effects of the two types of social capital are mainly derived from the effects of informal finance and access to medical resources. Based on the above findings, this paper puts forward policy recommendations.

SELEÇÃO DE REFERÊNCIAS
Detalhe da pesquisa