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1.
Cancer Cell Int ; 24(1): 92, 2024 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-38431620

RESUMO

BACKGROUND: Cholangiocarcinoma represents a malignant neoplasm originating from the hepatobiliary tree, with a subset of tumors developing inside the liver. Intrahepatic cholangiocarcinomas (ICC) commonly exhibit an asymptomatic presentation, rendering both diagnosis and treatment challenging. Cuproptosis, an emerging regulated cell death pathway induced by copper ions, has garnered attention recently. As cancer cells show altered copper metabolism and comparatively higher copper needs, cuproptosis may play a role in the development of ICC. However, studies investigating this possibility are currently lacking. METHODS: Single-cell and bulk RNA sequence data were analyzed, and correlations were established between the expression of cuproptosis-related molecules and ICC patient survival. Genes with predicting survival were used to create a CUPT score using Cox and LASSO regression and tumor mutation burden (TMB) analysis. The CIBERSORT software was employed to characterize immune cell infiltration within the tumors. Furthermore, immune infiltration prediction, biological function enrichment, and drug sensitivity analyses were conducted to explore the potential implications of the cuproptosis-related signature. The effects of silencing solute carrier family 39 member 4 gene (SLC39A4) expression using siRNA were investigated using assays measuring cell proliferation, colony formation, and cell migration. Key genes of cuproptosis were detected by western blotting. RESULTS: The developed CUPT score divided patients into high and low CUPT score groups. Those with a low score had significantly better prognosis and longer survival. In contrast, high CUPT scores were associated with worse clinical outcomes and significantly higher TMB. Comparisons of the two groups also indicated differences in the immune infiltrate present in the tumors. Finally, we were able to identify 95 drugs potentially affecting the cuproptosis pathway. Some of these might be effective in the treatment of ICC. The in vitro experiments revealed that suppressing the expression of SLC39A4 in ICC cell lines resulted in reduced cell proliferation, colony formation, and cell migration. It also led to an increase in cell death and the upregulation of key genes associated with cuproptosis, namely ferredoxin 1 (FDX1) and dihydrolipoyl transacetylase (DLAT). These findings strongly suggest that this cuproptosis-associated molecule may play a pivotal role in the development and metastasis of ICC. CONCLUSIONS: Changes in the expression of a cuproptosis-related gene signature can predict the clinical prognosis of ICC with considerable accuracy. This supports the notion that cuproptosis influences the diversity and complexity of the immune microenvironment, mutational landscape, and biological behavior of ICC. Understanding this pathway better may hold promise for the development of innovative strategies in the management of this disease.

2.
Reprod Med Biol ; 23(1): e12567, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38528990

RESUMO

Purpose: The intergenerational effects of ionizing radiation remain controversial. Extensive insights have been revealed for DNA mutations and cancer incidence in progeny, yet many of these results were obtained by immediate post-radiation mating. However, conception at short times after radiation exposure is likely to be avoided. After a long period of fertility recovery, whether unexposed sperm derived from exposed spermatogonia would challenge the health of the offspring is not yet clearly demonstrated. Methods: Ten-week-old C57BL/6J males underwent whole-body acute γ irradiation at 0 and 6.4 Gy. Testes and sperm were collected at different times after radiation to examine reproductive changes. The reproductive, metabolic, and neurodevelopmental parameters were measured in the offspring of controls and the offspring derived from irradiated undifferentiated spermatogonia. Results: Paternal fertility was lost after acute 6.4 Gy γ radiation and recovered at 10-11 weeks post irradiation in mice. The reproductive, metabolic, and neurodevelopmental health of offspring born to irradiated undifferentiated spermatogonia were comparable to those of controls. Conclusion: The male mice could have healthy offspring after recovery from the damage caused by ionizing radiation.

3.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 37(3): 502-511, 2020 Jun 25.
Artigo em Chinês | MEDLINE | ID: mdl-32597093

RESUMO

Brain-controlled wheelchair (BCW) is one of the important applications of brain-computer interface (BCI) technology. The present research shows that simulation control training is of great significance for the application of BCW. In order to improve the BCW control ability of users and promote the application of BCW under the condition of safety, this paper builds an indoor simulation training system based on the steady-state visual evoked potentials for BCW. The system includes visual stimulus paradigm design and implementation, electroencephalogram acquisition and processing, indoor simulation environment modeling, path planning, and simulation wheelchair control, etc. To test the performance of the system, a training experiment involving three kinds of indoor path-control tasks is designed and 10 subjects were recruited for the 5-day training experiment. By comparing the results before and after the training experiment, it was found that the average number of commands in Task 1, Task 2, and Task 3 decreased by 29.5%, 21.4%, and 25.4%, respectively ( P < 0.001). And the average number of commands used by the subjects to complete all tasks decreased by 25.4% ( P < 0.001). The experimental results show that the training of subjects through the indoor simulation training system built in this paper can improve their proficiency and efficiency of BCW control to a certain extent, which verifies the practicability of the system and provides an effective assistant method to promote the indoor application of BCW.


Assuntos
Interfaces Cérebro-Computador , Potenciais Evocados Visuais , Treinamento por Simulação , Cadeiras de Rodas , Encéfalo , Eletroencefalografia , Humanos
5.
Sheng Li Xue Bao ; 69(3): 325-334, 2017 Jun 25.
Artigo em Chinês | MEDLINE | ID: mdl-28638926

RESUMO

Transcutaneous electrical nerve stimulation (TENS), as a non-pharmacological and non-invasive analgesic therapy with low-cost, has been widely used to relieve pain in various clinical applications, by delivering current pulses to the skin area to activate the peripheral nerve fibers. Nevertheless, analgesia induced by TENS varied in the clinical practice, which could be caused by the fact that TENS with different stimulus parameters has different biological mechanisms in relieving pain. Therefore, to advance our understanding of TENS in various basic and clinical studies, we discussed (1) neurophysiological and biochemical mechanisms of TENS-induced analgesia; (2) relevant factors that may influence analgesic effects of TENS from the perspectives of stimulus parameters, including stimulated position, pulse parameters (current intensity, frequency, and pulse width), stimulus duration and used times in each day; and (3) applications of TENS in relieving clinical pain, including post-operative pain, chronic low back pain and labor pain. Finally, we propose that TENS may involve multiple and complex psychological neurophysiological mechanisms, and suggest that different analgesic effects of TENS with different stimulus parameters should be taken into consideration in clinical applications. In addition, to optimize analgesic effect, we recommend that individual-based TENS stimulation parameters should be designed by considering individual differences among patients, e.g., adaptively adjusting the stimulation parameters based on the dynamic ratings of patients' pain.


Assuntos
Analgesia/métodos , Manejo da Dor , Estimulação Elétrica Nervosa Transcutânea , Humanos , Medição da Dor , Pele
6.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 34(1): 27-33, 2017 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-29717583

RESUMO

In order to explore the feasibility of applying magnetic detection electrical impedance tomography(MDEIT) on respiratory monitoring, aiming at the forward problem of magnetic detection electrical impedance tomography, we calculated the electric potential and current density distribution inside the imaging object by using the finite element method. We then got magnetic induction intensity outside the object at the end of exhaling and inhaling according to Biot-Savart's law. The results showed that the magnetic induction intensity at the end of inhaling was 8.875%,less than that at the end of exhaling. By the simulation results, we could understand the difference of magnetic induction intensity value surrounding the lung at the end of exhaling and inhaling due to the change of lung volume and electrical conductivity distribution better. Our research laid the foundation for the late image reconstruction and clinical disease detection.


Assuntos
Magnetismo , Algoritmos , Simulação por Computador , Impedância Elétrica , Humanos , Interpretação de Imagem Assistida por Computador/métodos , Processamento de Imagem Assistida por Computador/métodos , Imagens de Fantasmas , Tomografia/métodos
7.
Bioelectromagnetics ; 37(7): 481-92, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27438778

RESUMO

Time-varying electromagnetic fields (EMF) can induce some physiological effects in neuronal tissues, which have been explored in many applications such as transcranial magnetic stimulation. Although transmembrane potentials and induced currents have already been the subjects of many theoretical studies, most previous works about this topic are mainly completed by utilizing Maxwell's equations, often by solving a Laplace equation. In previous studies, cells were often considered to be three-compartment models with different electroconductivities in different regions (three compartments are often intracellular regions, membrane, and extracellular regions). However, models like that did not take dynamic ion channels into consideration. Therefore, one cannot obtain concrete ionic current changes such as potassium current change or sodium current change by these models. The aim of the present work is to present a new and more detailed model for calculating transmembrane potentials and ionic currents induced by time-varying EMF. Equations used in the present paper originate from Nernst-Plank equations, which are ionic current-related equations. The main work is to calculate ionic current changes induced by EMF exposure, and then transmembrane potential changes are calculated with Hodgkin-Huxley model. Bioelectromagnetics. 37:481-492, 2016. © 2016 Wiley Periodicals, Inc.


Assuntos
Campos Eletromagnéticos , Potenciais da Membrana/efeitos da radiação , Modelos Neurológicos , Neurônios/citologia , Neurônios/efeitos da radiação
8.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 33(3): 420-5, 2016 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-29708716

RESUMO

In order to realize sleep staging automatically and conveniently,we used support vector machine(SVM)to analyze the correlation between heart rate variability and sleep stage experimentally.R-R intervals(RRIs)from 33 cases of sleep clinical data of Tianjin Thoracic Hospital were extracted and analyzed by principal component analysis(PCA).The SVM method was used to establish the model and predict the five sleep stages.The prediction accuracy of three-sleep-stage was higher than 80%,in contrast to sleep scoring annotations marked by physiological experts based on electroencephalogram(EEG)golden standard.The result showed that there was a good correlation between heart rate variability and sleep staging.This method is an important supplement to the traditional sleep staging method and has a great value for clinical application.


Assuntos
Frequência Cardíaca , Fases do Sono , Máquina de Vetores de Suporte , Eletroencefalografia , Humanos , Polissonografia , Análise de Componente Principal
9.
J Transl Med ; 13: 298, 2015 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-26363929

RESUMO

BACKGROUND: The strategy of using fecal microbiota transplantation (FMT) for refractory ulcerative colitis (UC) remains unclear if single FMT failed to induce remission. This study aimed to evaluate the efficacy and safety of a designed step-up FMT strategy for the steroid-dependent UC. METHODS: Fifteen patients with steroid-dependent UC were enrolled, and treated with step-up FMT strategy. Follow-up clinical data was collected for a minimum of 3 months. Fecal microbiota composition before and post FMT of patients and related donors were analyzed by 16S rRNA sequencing. RESULTS: Eight of fourteen (57.1 %) patients achieved clinical improvement and were able to discontinue steroids following step-up FMT. One patient was lost to follow-up. Among the 8 patients who responded, five (35.7 %) received one FMT therapy, one (7.1 %) received two FMTs, and two (14.2 %) received two FMTs plus a scheduled course of steroids. Four (28.6 %) of the 8 patients who responded maintained long-term remission during follow-up (3-18 months). Six patients (42.9 %) failed to meet the criteria of clinical improvement and maintained steroid dependence, though three experienced transient or partial improvement. Microbiota analysis showed that FMT altered the composition greatly, and a microbiota composition highly similar to that of the donor emerged in the patients with successful treatment. No severe adverse events occurred during treatment and follow-up. CONCLUSIONS: Step-up FMT strategy shows promise as a therapeutic strategy for patients with steroid-dependent UC, likely due to the successful restructuring of gut microbial composition. TRIAL REGISTRATION: ClinicalTrials.gov, Number NCT01790061.


Assuntos
Corticosteroides/uso terapêutico , Colite Ulcerativa/terapia , Transplante de Microbiota Fecal , Fezes/microbiologia , Adolescente , Adulto , Criança , Colite Ulcerativa/tratamento farmacológico , Feminino , Humanos , Masculino , Microbiota , Pessoa de Meia-Idade , Projetos Piloto , Estudos Prospectivos , Manejo de Espécimes , Resultado do Tratamento , Adulto Jovem
10.
Nanotechnology ; 26(42): 425102, 2015 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-26422130

RESUMO

In living cells, due to the selective permeability and complicated cellular environment, the uptake efficiency and fluorescence decay of organic dyes during dye-labeling may be influenced, which may eventually result in poor fluorescent imaging. In this work, a protocol of UCNs@mSiO2-(FA and Azo) core-shell nanocarriers was designed and prepared successfully. The core-shell nanocarriers were assembled from two parts, including a mesoporous silica shell surface modified by folate (FA) and azobenzene (Azo), and an upconverting nanocrystal (UCN) core. The mesoporous silica shell is used for loading organic dyes and conjugating folate which helps to enhance the cellular uptake of nanocarriers. The UCN core works as a transducer to convert near infrared (NIR) light to local UV and visible light to activate a back-and-forth wagging motion of azobenzene molecules on the surface, while the azobenzene acts as a molecular impeller for propelling the release of organic dyes. The nanocarriers of loading organic dyes can maintain the stability of the fluorescent imaging effect better than free organic dyes. The experimental results show that with the help of the nanoparticle, cell uptake efficiency of the model dyes of rhodamine and 4', 6-diamidino-2-phenylindole (DAPI) was significantly improved. The release of dyes can only be triggered by NIR light exposure and their quantity is highly dependent on the duration of NIR light exposure, thus realizing NIR-regulated dye release spatiotemporally. Our work may open a novel avenue for precisely controlling UCN-based living cell imaging in biotechnology and diagnostics, as well as studying cell dynamics, cell-cell interactions, and tissue morphogenesis.


Assuntos
Portadores de Fármacos/química , Corantes Fluorescentes/química , Nanopartículas/química , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Compostos Azo , Preparações de Ação Retardada/química , Preparações de Ação Retardada/farmacocinética , Corantes Fluorescentes/farmacocinética , Ácido Fólico , Células HeLa , Humanos , Indóis , Raios Infravermelhos , Imagem Óptica , Rodaminas , Dióxido de Silício
11.
Prenat Diagn ; 35(8): 816-22, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26013964

RESUMO

OBJECTIVE: Sufficient fetal DNA in a maternal plasma sample is required for accurate aneuploidy detection via noninvasive prenatal testing, thus highlighting a need to understand the factors affecting fetal fraction. METHOD: The MaterniT21™ PLUS test uses massively parallel sequencing to analyze cell-free fetal DNA in maternal plasma and detect chromosomal abnormalities. We assess the impact of a variety of factors, both maternal and fetal, on the fetal fraction across a large number of samples processed by Sequenom Laboratories. RESULTS: The rate of increase in fetal fraction with increasing gestational age varies across the duration of the testing period and is also influenced by fetal aneuploidy status. Maternal weight trends inversely with fetal fraction, and we find no added benefit from analyzing body mass index or blood volume instead of weight. Strong correlations exist between fetal fractions from aliquots taken from the same patient at the same blood draw and also at different blood draws. CONCLUSION: While a number of factors trend with fetal fraction across the cohort as a whole, they are not the sole determinants of fetal fraction. In this study, the variability for any one patient does not appear large enough to justify postponing testing to a later gestational age.


Assuntos
Aneuploidia , DNA/sangue , Feto , Sequenciamento de Nucleotídeos em Larga Escala , Testes para Triagem do Soro Materno/métodos , Análise de Sequência de DNA/métodos , Índice de Massa Corporal , Sistema Livre de Células , Feminino , Idade Gestacional , Humanos , Gravidez , Estudos Retrospectivos
12.
Front Neurosci ; 18: 1359446, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38957184

RESUMO

Objective: The presence of mental fatigue seriously affects daily life and working conditions. Non-invasive transcranial electrical stimulation has become an increasingly popular tool for relieving mental fatigue. We investigated whether transcranial direct current stimulation (tDCS) and transcranial alternating current stimulation (tACS) could be used to alleviate the state of mental fatigue in a population of healthy young adults and compared their effects. Methods: We recruited 10 participants for a blank control, repeated measures study. Each participant received 15 min of anodal tDCS, α-tACS, and blank stimulation. Participants were required to fill in the scale, perform the test task and collect ECG signals in the baseline, fatigue and post-stimulus states. We then assessed participants' subjective fatigue scale scores, test task accuracy and HRV characteristics of ECG signals separately. Results: We found that both anodal tDCS and α-tACS significantly (P < 0.05) reduced subjective fatigue and improved accuracy on the test task compared to the blank group, and the extent of change was greater with tACS. For the HRV features extracted from ECG signals. After tACS intervention, SDNN (t = -3.241, P = 0.002), LF (t = -3.511, P = 0.001), LFn (t = -3.122, P = 0.002), LFn/HFn (-2.928, P = 0.005), TP (t = -2.706, P = 0.008), VLF (t = -3.002, P = 0.004), SD2 (t = -3.594, P = 0.001) and VLI (t = -3.564, P = 0.001) showed a significant increasing trend, and HFn (t = 3.122, P = 0.002), SD1/SD2 (t = 3.158, P = 0.002) and CCM_1 (t = 3.106, P = 0.003) showed a significant decreasing trend. After tDCS intervention, only one feature, TINN, showed a significant upward trend (P < 0.05). The other features showed non-significant changes but roughly the same trend as the tACS group. Conclusion: Both tDCS and α-tACS can be effective in relieving mental fatigue, and α-tACS is more effective than tDCS. This study provides theoretical support for tDCS with α-tACS having a alleviating effect on mental fatigue and the use of ECG as a valid objective assessment tool.

13.
ACS Omega ; 9(16): 18119-18126, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38680373

RESUMO

The wedge-shaped sample cell, by offering a comprehensive representation of scattering information in turbid media, significantly enhances the informational content conveyed by spectral images compared to flat sample cells. To further refine the accuracy of turbid medium component detection utilizing wedge-shaped sample cells, this work undertakes modeling and analysis of the influence of different wedge angles on detection precision. In this study, employing a 5° gradient in the incident angle of light, we investigate the impact of incident angles ranging from 10 to 45° on the turbid medium component analysis. Validation experiments are performed by utilizing solutions of Indian ink and fat emulsion at varying ratios. Experimental findings demonstrate that under identical experimental conditions, the wedge-shaped sample cell model at an incident angle of 35° yields optimal analysis results. Utilizing partial least-squares regression (PLSR) for the corresponding optical parameters, the highest value of Rp reached 0.980, with an RMSEP of 0.002. When compared to the model with a 30° incident angle, Rp increased by 0.033, and RMSEP decreased by 0.008. In comparison to the flat sample cell model, Rp increased by 0.041, and RMSEP decreased by 0.004. This study, through continuous variation of wedge angles and PLSR modeling and prediction, further enhances the accuracy of turbid medium component detection, laying an experimental foundation for subsequent analysis of turbid medium components based on wedge-shaped sample cells.

14.
Brain Sci ; 14(4)2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38672006

RESUMO

Non-invasive neuromodulation techniques are widely utilized to study and improve cognitive function, with the aim of modulating different cognitive processes. For workers performing high-intensity mental and physical tasks, extreme fatigue may not only affect their working efficiency but may also lead to cognitive decline or cognitive impairment, which, in turn, poses a serious threat to their physical health. The use of non-invasive neuromodulation techniques has important research value for improving and enhancing cognitive function. In this paper, we review the research status, existing problems, and future prospects of transcranial direct current stimulation (tDCS), transcranial alternating current stimulation (tACS), transcranial magnetic stimulation (TMS), and transcutaneous acupoint stimulation (TAS), which are the most studied physical methods in non-invasive neuromodulation techniques to improve and enhance cognition. The findings presented in this paper will be of great reference value for the in-depth study of non-invasive neuromodulation techniques in the field of cognition.

15.
Biochim Biophys Acta Mol Basis Dis ; 1870(1): 166885, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37714499

RESUMO

Perioperative hyperoxia therapy is of great significance to save the lives of patients, but little is known about the possible mechanisms that induce hyperoxia-induced acute lung injury (HALI) and the measures for clinical prevention and treatment. In this experiment, the models were established with a feeding chamber with automatic regulation of oxygen concentration. The results showed that with the increase in inhaled oxygen concentration and the prolongation of exposure time, the severity of lung injury also increases significantly, reaching the diagnostic indication of HALI after 48 h of inhaling 95 % oxygen concentration. Subsequently, according to the dynamic changes of apoptosis in lung specimens, and the expression changes in Sig-1R-regulated ER stress pathway proteins (Sig-1R, GRP78, p-PERK, ATF6, IRE1, Caspase-12, ATF4, CHOP, Caspase-3 and p-JNK), it was confirmed that the Sig-1R-regulated ER stress signaling pathway was involved in the occurrence of HALI. To explore the preventive and therapeutic effects of routine clinical medication on HALI during the perioperative period, our research group selected dexmedetomidine (Dex) with lung protection. The experimental results revealed that Dex partially reversed the changes in the expression levels of Sig-1R-regulated ER stress pathway proteins. These results preliminarily confirmed that Dex may inhibit apoptosis induced by high oxygen concentration through the Sig-1R-regulated ER stress signaling pathway, thus playing a protective role in HALI.


Assuntos
Lesão Pulmonar Aguda , Dexmedetomidina , Hiperóxia , Humanos , Dexmedetomidina/farmacologia , Dexmedetomidina/uso terapêutico , Hiperóxia/complicações , Estresse do Retículo Endoplasmático , Lesão Pulmonar Aguda/tratamento farmacológico , Lesão Pulmonar Aguda/etiologia , Lesão Pulmonar Aguda/prevenção & controle , Oxigênio , Receptor Sigma-1
16.
J Biomed Res ; : 1-15, 2024 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-38807419

RESUMO

Ischemia-reperfusion injury (IRI) remains inevitable in liver surgeries, macrophages play a critical role in the development of IRI, but little is known about the macrophages regulate pathogenesis of IRI. Based on target-guided screening, we identified a small 3 kDa peptide (SjDX5-271) from various schistosome egg-derived peptides that induced M2 macrophage polarization. SjDX5-271 treatment protected the mice against liver IRI through promoting M2 macrophage polarization, the protective effect was abrogated when the macrophages were depleted. Transcriptomic sequencing showed that the TLR signaling pathway was significantly inhibited in macrophages derived from the SjDX5-271 treatment group. We further identified that SjDX5-271 promotes M2 macrophage polarization by inhibiting the TLR4/MyD88/NF-κB signaling pathway and further alleviates hepatic inflammation in liver IRI. Collectively, SjDX5-271 exhibits promising therapeutic effects in IRI and represents a novel therapeutic approach for IRI, even in immune-related diseases. This study revealed the development of a new biologic from the parasite and enhanced our understanding of host-parasite interplay, providing a blueprint for future therapies for immune-related diseases.

17.
Neuroimage ; 78: 75-82, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23587685

RESUMO

Gamma-aminobutyric acid (GABA) is the primary inhibitory neurotransmitter in the brain. Although measurements of GABA levels in vivo in the human brain using edited proton magnetic resonance spectroscopy ((1)H-MRS) have been established for some time, it is has not been established how regional GABA levels vary with age in the normal human brain. In this study, 49 healthy men and 51 healthy women aged between 20 and 76 years were recruited and J-difference edited spectra were recorded at 3T to determine the effect of age on GABA levels, and to investigate whether there are regional and gender differences in GABA in mesial frontal and parietal regions. Because the signal detected at 3.02 ppm using these experimental parameters is also expected to contain contributions from both macromolecules (MM) and homocarnosine, in this study the signal is labeled GABA+ rather than GABA. Significant negative correlations were observed between age and GABA+ in both regions studied (GABA+/Cr: frontal region, r=-0.68, p<0.001, parietal region, r=-0.54, p<0.001; GABA+/NAA: frontal region, r=-0.58, p<0.001, parietal region, r=-0.49, p<0.001). The decrease in GABA+ with age in the frontal region was more rapid in women than men. Evidence of a measureable decline in GABA is important in considering the neurochemical basis of the cognitive decline that is associated with normal aging.


Assuntos
Envelhecimento/metabolismo , Química Encefálica , Encéfalo/metabolismo , Espectroscopia de Ressonância Magnética/métodos , Ácido gama-Aminobutírico/análise , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Caracteres Sexuais , Adulto Jovem
18.
Prenat Diagn ; 33(6): 591-7, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23592550

RESUMO

OBJECTIVE: Whole-genome sequencing of circulating cell free (ccf) DNA from maternal plasma has enabled noninvasive prenatal testing for common autosomal aneuploidies. The purpose of this study was to extend the detection to include common sex chromosome aneuploidies (SCAs): [47,XXX], [45,X], [47,XXY], and [47,XYY] syndromes. METHOD: Massively parallel sequencing was performed on ccf DNA isolated from the plasma of 1564 pregnant women with known fetal karyotype. A classification algorithm for SCA detection was constructed and trained on this cohort. Another study of 411 maternal samples from women with blinded-to-laboratory fetal karyotypes was then performed to determine the accuracy of the classification algorithm. RESULTS: In the training cohort, the new algorithm had a detection rate (DR) of 100% (95%CI: 82.3%, 100%), a false positive rate (FPR) of 0.1% (95%CI: 0%, 0.3%), and nonreportable rate of 6% (95%CI: 4.9%, 7.4%) for SCA determination. The blinded validation yielded similar results: DR of 96.2% (95%CI: 78.4%, 99.8%), FPR of 0.3% (95%CI: 0%, 1.8%), and nonreportable rate of 5% (95%CI: 3.2%, 7.7%) for SCA determination CONCLUSION: Noninvasive prenatal identification of the most common sex chromosome aneuploidies is possible using ccf DNA and massively parallel sequencing with a high DR and a low FPR.


Assuntos
Aneuploidia , Diagnóstico Pré-Natal/métodos , Análise de Sequência de DNA/métodos , Aberrações dos Cromossomos Sexuais , Cromossomos Humanos X/genética , Cromossomos Humanos Y/genética , Estudos de Coortes , DNA/sangue , DNA/genética , Feminino , Feto/metabolismo , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino , Mães , Gravidez/sangue
19.
Micron ; 173: 103519, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37556899

RESUMO

The micro-operation robot is widely used in micro-manipulations of biological cells in biological and medical experiments. It plans and controls micro-effector movement based on image feedback information to achieve micro-operations. However, the displacement information of the micro-effector on the x-y plane can be obtained from the image, but not the position information of the micro-effector in the z-axis direction. This makes the micro-effector movement in the z-axis direction discontinuous, which is time-consuming and reduces operational efficiency. In this study, starting from the optical imaging principle of Robert Hoffman modulation contrast method (RC), we propose a defocus detection method for the RC observation mode of an optical microscope. Our method can determine the direction of defocus, which is not available in previous defocusing detection methods. Utilizing this method, we achieve rapid focus for the micro-effector while it is moving along the z-axis direction.

20.
Front Public Health ; 11: 1112547, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37006539

RESUMO

Big data technology plays an important role in the prevention and control of public health emergencies such as the COVID-19 pandemic. Current studies on model construction, such as SIR infectious disease model, 4R crisis management model, etc., have put forward decision-making suggestions from different perspectives, which also provide a reference basis for the research in this paper. This paper conducts an exploratory study on the construction of a big data prevention and control model for public health emergencies by using the grounded theory, a qualitative research method, with literature, policies, and regulations as research samples, and makes a grounded analysis through three-level coding and saturation test. Main results are as follows: (1) The three elements of data layer, subject layer, and application layer play a prominent role in the digital prevention and control practice of epidemic in China and constitute the basic framework of the "DSA" model. (2) The "DSA" model integrates cross-industry, cross-region, and cross-domain epidemic data into one system framework, effectively solving the disadvantages of fragmentation caused by "information island". (3) The "DSA" model analyzes the differences in information needs of different subjects during an outbreak and summarizes several collaborative approaches to promote resource sharing and cooperative governance. (4) The "DSA" model analyzes the specific application scenarios of big data technology in different stages of epidemic development, effectively responding to the disconnection between current technological development and realistic needs.


Assuntos
COVID-19 , Saúde Pública , Humanos , Saúde Pública/métodos , COVID-19/epidemiologia , COVID-19/prevenção & controle , Emergências , Big Data , Pandemias/prevenção & controle , Teoria Fundamentada
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