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1.
Math Biosci Eng ; 20(9): 17324-17355, 2023 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-37920057

RESUMO

In this paper, a double association-based evolutionary algorithm (denoted as DAEA) is proposed to solve many-objective optimization problems. In the proposed DAEA, a double association strategy is designed to associate solutions with each subspace. Different from the existing association methods, the double association strategy takes the empty subspace into account and associates it with a promising solution, which can facilitate the exploration of unknown areas. Besides, a new quality evaluation scheme is developed to evaluate the quality of each solution in subspace, where the convergence and diversity of each solution is first measured, and in order to evaluate the diversity of solutions more finely, the global diversity and local diversity is designed to measure the diversity of each solution. Then, a dynamic penalty coefficient is designed to balance the convergence and diversity by penalizing the global diversity distribution of solutions. The performance of DAEA is validated by comparing with five state-of-the-art many-objective evolutionary algorithms on a number of well-known benchmark problems with up to 20 objectives. Experimental results show that our DAEA has high competitiveness in solving many-objective optimizatiopn problems compared with the other compared algorithms.

2.
Opt Lett ; 48(11): 3075-3078, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37262284

RESUMO

The high-precision and portable nonlinear magneto-optical rotation (NMOR) atomic magnetometer has significant potential in the direction of magnetic field measurement under a geomagnetic environment. Here, we propose a single-beam NMOR atomic magnetometer with amplitude modulation based on a fiberized electro-optic modulator (EOM) for the first time, to the best of our knowledge, which provides a feasible scheme for the integrated design. A theoretical model of the system response signal as a function of the modulation amplitude is established by a Jones matrix. Based on the theoretical model, the influence mechanism of the modulation amplitude on the system response signal is further analyzed and the optimal modulation parameters can be determined. Finally, a sensitivity of 42.67 fT/Hz1/2 at 50-µT magnetic field is achieved. The proposed scheme is also applicable to other magnetometers under a geomagnetic environment.

3.
Colloids Surf B Biointerfaces ; 222: 113086, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36542953

RESUMO

The host-material interface is critical in determining the successful integration of medical devices into human tissue. The surface topography can regulate the fibrous capsule formation around implants through macrophage polarization, but the exact mechanism remains unclear. In this study, four types of microgrooves (10 or 50 µm in groove depths and 50 or 200 µm in groove widths) were fabricated on polydimethylsiloxane (PDMS) using lithography. The microgroove surfaces were characterized using the laser scanning confocal microscopy and fourier transform infrared spectroscopy. The effect of surface topography on macrophage phenotypes and conditioned medium (CM) collected from macrophages on human foreskin fibroblast 1 (HFF-1) were investigated. The result revealed that a deeper and narrower microgroove structure means a rougher surface. Macrophages tended to adhere and aggregate on group 50-50 surface (groove depths and widths of 50 µm). THP-1 cell polarized toward both inflammatory M1 and anti-inflammatory M2 macrophages on the surface of each group. Meanwhile, CM from macrophages culture on PDMS differentially up-regulated the proliferation, migration and fibrosis of HFF-1. Among them, the group 50-50 had the strongest promoting effect. In vivo, the inflammatory response and fibrotic capsule around the implants were observed at 1 week and 4 weeks. As time passed, the inflammatory response decreased, while the capsule thickness continued to increase. The rough material surface was more inclined to develop a severe fibrotic encapsulation. In conclusion, this finding further suggested a potential immunomodulatory effect of macrophages in mediating the fibrotic response to implants and facilitated the design of biomaterial interfaces for improving tissue integration.


Assuntos
Materiais Biocompatíveis , Próteses e Implantes , Humanos , Propriedades de Superfície , Materiais Biocompatíveis/química , Fibroblastos/fisiologia , Macrófagos
4.
Neuron ; 111(2): 220-235.e9, 2023 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-36379214

RESUMO

Schizophrenia (SZ) and bipolar disorder (BP) are highly heritable major psychiatric disorders that share a substantial portion of genetic risk as well as their clinical manifestations. This raises a fundamental question of whether, and how, common neurobiological pathways translate their shared polygenic risks into shared clinical manifestations. This study shows the miR-124-3p-AMPAR pathway as a key common neurobiological mediator that connects polygenic risks with behavioral changes shared between these two psychotic disorders. We discovered the upregulation of miR-124-3p in neuronal cells and the postmortem prefrontal cortex from both SZ and BP patients. Intriguingly, the upregulation is associated with the polygenic risks shared between these two disorders. Seeking mechanistic dissection, we generated a mouse model that upregulates miR-124-3p in the medial prefrontal cortex. We demonstrated that the upregulation of miR-124-3p increases GRIA2-lacking calcium-permeable AMPARs and perturbs AMPAR-mediated excitatory synaptic transmission, leading to deficits in the behavioral dimensions shared between SZ and BP.


Assuntos
Transtorno Bipolar , MicroRNAs , Esquizofrenia , Camundongos , Animais , Esquizofrenia/genética , Esquizofrenia/metabolismo , Transtorno Bipolar/genética , Transtorno Bipolar/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Herança Multifatorial , Córtex Pré-Frontal/metabolismo
5.
Opt Express ; 30(14): 25509-25521, 2022 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-36237079

RESUMO

We investigate the magnetic pulse response of the optically pumped comagnetometer operated in the spin-exchange relaxation-free (SERF) regime. The pulse response model describing the evolution of the coupled spin ensemble of alkali metal and noble gas during and after the pulse is established for the first time. A three-beam comagnetometer is created with a circularly and two linearly polarized lasers to detect the responses in the three axes of the comagnetometer simultaneously and independently. The results indicate that the response to the small pulse excitation is dominated by the electron spins, while the response to the large pulse excitation and both responses after the pulse excitation consist of a fast and a slow oscillation, which are dominated by the electron spins and nuclear spins, respectively. We also observe novel dynamics of the coupled spin ensemble when the nuclear spins are tipped far away from equilibrium. The theory and method presented here can not only facilitate the investigation on the dynamics of the optically pumped coupled spin ensemble, but also shed light on the application of the pulse modulation technology in the SERF comagnetometer.

6.
BMC Urol ; 22(1): 25, 2022 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-35197026

RESUMO

BACKGROUND: Fournier's gangrene (FG), a urological emergency with high mortality, is an infectious necrotizing fasciitis of the perineal and genital regions. The majority of FG is caused by polymicrobial organisms involving mixed aerobes and anaerobes but rarely reveals Actinomyces species. CASE PRESENTATION: We report a healthy 67-year-old Asian male who presented with rapidly progressive painful swelling of the scrotum. Clinically diagnosed with FG, the patient underwent an emergency radical debridement, followed by broad-spectrum antibiotics and negative pressure wound therapy. The identification of the causative microorganisms showed Actinomyces turicensis and the antibiotic treatment was adjusted accordingly. After wound bed preparation, we took split-thickness skin grafts to cover the scrotal wound. Active management to minimize faecal contamination was applied throughout the whole course of treatment and repair. The patient was satisfied with the outcome. This was an extremely rare case of A. turicensis as the main causative pathogen of FG. CONCLUSIONS: FG due to Actinomyces species is rarely reported, but we should still consider this pathogenic microorganism that has long been neglected.


Assuntos
Actinomycetaceae/isolamento & purificação , Infecções por Actinomycetales/complicações , Gangrena de Fournier/microbiologia , Escroto/patologia , Infecções por Actinomycetales/tratamento farmacológico , Idoso , Antibacterianos/uso terapêutico , Desbridamento , Gangrena de Fournier/cirurgia , Humanos , Masculino , Escroto/microbiologia , Escroto/cirurgia
7.
Front Psychol ; 12: 686954, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34122286

RESUMO

The sudden outbreak of coronavirus disease 2019 (COVID-19) has caused a huge impact on the Chinese residents' health and economic level. In the pandemic background, the country and its institutions have introduced pandemic-related insurance to stabilize the national situation. At this stage, insurance has played an increasingly important role in social life. With the popularization of insurance, the idea of buying insurance to avoid risk has gradually become popular among people. Among them, the New Rural Cooperative Medical System (NRCMS) has been farmers' common choice. The NRCMS, a mutual aid system created by farmers spontaneously in the country, plays a great role in guaranteeing farmers access to basic health services, alleviating poverty caused by disease and returning to poverty due to disease, and promoting poverty alleviation and rural revitalization. Given this backdrop, we study the efficiency of the NRCMS that can effectively promote poverty alleviation and rural revitalization and ensure the people's happy life. Implementing the Data Envelopment Analysis (DEA), we find that technological progress is one of the main factors influencing the efficiency of the NRCMS. Therefore, it is important to improve the technology for providing the efficiency of the NRCMS and promoting the happiness of the society.

8.
Channels (Austin) ; 14(1): 53-58, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32093550

RESUMO

Severe local acidosis causes tissue damage and pain, and is associated with many diseases, including cerebral and cardiac ischemia, cancer, infection, and inflammation. However, the molecular mechanisms of the cellular response to extracellular acidic environment are not fully understood. We recently identified a novel and evolutionarily conserved membrane protein, PAC (also known as PACC1 or TMEM206), encoding the proton-activated chloride (Cl-) channel, whose activity is widely observed in human cell lines. We demonstrated that genetic deletion of Pac abolished the proton-activated Cl- currents in mouse neurons and also attenuated the acid-induced neuronal cell death and brain damage after ischemic stroke. Here, we show that the proton-activated Cl- currents are also conserved in primary rat cortical neurons, with characteristics similar to those observed in human and mouse cells. Pac gene knockdown nearly abolished the proton-activated Cl- currents in rat neurons and reduced the neuronal cell death triggered by acid treatment. These data further support the notion that activation of the PAC channel and subsequent Cl- entry into neurons during acidosis play a pathogenic role in acidotoxicity and brain injury.


Assuntos
Ácidos/toxicidade , Canais de Cloreto/metabolismo , AVC Isquêmico/metabolismo , Animais , Morte Celular/efeitos dos fármacos , Linhagem Celular , Canais de Cloreto/efeitos dos fármacos , Canais de Cloreto/genética , Humanos , Concentração de Íons de Hidrogênio , AVC Isquêmico/genética , Camundongos , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Reação em Cadeia da Polimerase em Tempo Real
9.
Epilepsia ; 58(8): 1451-1461, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28586508

RESUMO

OBJECTIVE: The mutant γ-aminobutyric acid type A (GABAA ) receptor γ2(Q390X) subunit (Q351X in the mature peptide) has been associated with the epileptic encephalopathy, Dravet syndrome, and the epilepsy syndrome genetic epilepsy with febrile seizures plus (GEFS+). The mutation generates a premature stop codon that results in translation of a stable truncated and misfolded γ2 subunit that accumulates in neurons, forms intracellular aggregates, disrupts incorporation of γ2 subunits into GABAA receptors, and affects trafficking of partnering α and ß subunits. Heterozygous Gabrg2+/Q390X knock-in (KI) mice had reduced cortical inhibition, spike wave discharges on electroencephalography (EEG), a lower seizure threshold to the convulsant drug pentylenetetrazol (PTZ), and spontaneous generalized tonic-clonic seizures. In this proof-of-principal study, we attempted to rescue these deficits in KI mice using a γ2 subunit gene (GABRG2) replacement therapy. METHODS: We introduced the GABRG2 allele by crossing Gabrg2+/Q390X KI mice with bacterial artificial chromosome (BAC) transgenic mice overexpressing HA (hemagglutinin)-tagged human γ2HA subunits, and compared GABAA receptor subunit expression by Western blot and immunohistochemical staining, seizure threshold by monitoring mouse behavior after PTZ-injection, and thalamocortical inhibition and network oscillation by slice recording. RESULTS: Compared to KI mice, adult mice carrying both mutant allele and transgene had increased wild-type γ2 and partnering α1 and ß2/3 subunits, increased miniature inhibitory postsynaptic current (mIPSC) amplitudes recorded from layer VI cortical neurons, reduced thalamocortical network oscillations, and higher PTZ seizure threshold. SIGNIFICANCE: Based on these results we suggest that seizures in a genetic epilepsy syndrome caused by epilepsy mutant γ2(Q390X) subunits with dominant negative effects could be rescued potentially by overexpression of wild-type γ2 subunits.


Assuntos
Epilepsias Mioclônicas/genética , Epilepsias Mioclônicas/terapia , Mutação/genética , Subunidades Proteicas/metabolismo , Receptores de GABA-A/genética , Receptores de GABA-A/metabolismo , Potenciais de Ação/efeitos dos fármacos , Potenciais de Ação/genética , Animais , Convulsivantes/toxicidade , Estimulação Elétrica , Humanos , Técnicas In Vitro , Potenciais Pós-Sinápticos Inibidores/efeitos dos fármacos , Potenciais Pós-Sinápticos Inibidores/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Vias Neurais/efeitos dos fármacos , Vias Neurais/fisiologia , Técnicas de Patch-Clamp , Pentilenotetrazol/toxicidade , Subunidades Proteicas/genética , Células Piramidais/efeitos dos fármacos , Células Piramidais/fisiologia , Córtex Somatossensorial/citologia , Tálamo/citologia
10.
Neurobiol Dis ; 50: 135-41, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23069679

RESUMO

The purpose of the study was to explore the pathogenic mechanisms underlying generalized epilepsy and febrile seizures plus (GEFS+) in a family with a novel γ2 subunit gene (GABRG2) frameshift mutation. Four affected and one unaffected individuals carried a c.1329delC GABRG2 mutation resulting in a subunit [γ2S(S443delC)] with a modified and elongated carboxy-terminus that is different from that of the wildtype γ2S subunit. We expressed the wildtype γ2S subunit and the predicted mutant γ2S(S443delC) subunit cDNAs in HEK293T cells and performed immunoblotting, flow cytometry and electrophysiology studies. The mutant subunit was translated as a stable protein that was larger than the wildtype γ2S subunit and was retained in the ER and not expressed on the cell surface membrane, suggesting GABRG2 haploinsufficiency. Peak GABA-evoked currents recorded from cells cotransfected with wildtype α1 and ß2 subunits and mutant γ2S subunits were significantly decreased and were comparable to α1ß2 receptor currents. S443delC is the first GABR epilepsy mutation predicted to abolish the natural stop codon and produce a stop codon in the 3' UTR that leads to translation of an extended peptide. The GEFS+ phenotype observed in this family is likely caused by γ2S subunit loss-of-function and possibly to dominant-negative suppression of α1ß2γ2 receptors. Many GABRG2 truncation mutations result in GEFS+, but the spectrum of phenotypic severity is wider, ranging from asymptomatic individuals to the Dravet syndrome. Mechanisms influencing the severity of the phenotype are therefore complex and difficult to correlate with its demonstrable functional effects.


Assuntos
Epilepsias Mioclônicas/genética , Epilepsias Mioclônicas/fisiopatologia , Receptores de GABA-A/genética , Adulto , Idoso , Sequência de Aminoácidos , Criança , Pré-Escolar , Eletroencefalografia , Epilepsias Mioclônicas/metabolismo , Feminino , Citometria de Fluxo , Mutação da Fase de Leitura , Genótipo , Humanos , Immunoblotting , Imuno-Histoquímica , Masculino , Microscopia Confocal , Pessoa de Meia-Idade , Dados de Sequência Molecular , Técnicas de Patch-Clamp , Linhagem , Fenótipo , Receptores de GABA-A/biossíntese
11.
Neurobiol Dis ; 48(1): 115-23, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22750526

RESUMO

The GABRG2 nonsense mutation, Q40X, is associated with the severe epilepsy syndrome, Dravet syndrome, and is predicted to generate a premature translation-termination codon (PTC) in the GABA(A) receptor γ2 subunit mRNA in a position that codes for the first amino acid of the mutant subunit. We determined the effects of the mutation on γ2 subunit mRNA and protein synthesis and degradation, as well as on α1ß2γ2 GABA(A) receptor assembly, trafficking and surface expression in HEK cells. Using bacterial artificial chromosome (BAC) constructs, we found that γ2(Q40X) subunit mRNA was degraded by nonsense mediated mRNA decay (NMD). Undegraded mutant mRNA was translated to a truncated peptide, likely the signal peptide, which was cleaved further. We also found that mutant γ2(Q40X) subunits did not assemble into functional receptors, thus decreasing GABA-evoked current amplitudes. The GABRG2(Q40X) mutation is one of several epilepsy-associated nonsense mutations that have the potential to be rescued by reading through the PTC, thus restoring full-length protein translation. As a first approach, we investigated the use of the aminoglycoside, gentamicin, to rescue translation of intact mutant subunits by inducing mRNA read-through. In the presence of gentamicin, synthesis of full length γ2 subunits was partially restored, and surface biotinylation and whole cell recording experiments suggested that rescued γ2 subunits could corporate into functional, surface GABA(A) receptors, indicating a possible direction for future therapy.


Assuntos
Códon sem Sentido , Epilepsias Mioclônicas/genética , Degradação do RNAm Mediada por Códon sem Sentido , Subunidades Proteicas/genética , Receptores de GABA-A/genética , Aminoglicosídeos/genética , Aminoglicosídeos/metabolismo , Códon de Terminação , Epilepsias Mioclônicas/metabolismo , Células HEK293 , Humanos , Subunidades Proteicas/metabolismo , Receptores de GABA-A/metabolismo
12.
J Neurosci ; 32(17): 5937-52, 2012 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-22539854

RESUMO

The intronic GABRG2 mutation, IVS6+2T→G, was identified in an Australian family with childhood absence epilepsy and febrile seizures (Kananura et al., 2002). The GABRG2 intron 6 splice donor site was found to be mutated from GT to GG. We generated wild-type and mutant γ2 subunit bacterial artificial chromosomes (BACs) driven by a CMV promoter and expressed them in HEK293T cells and expressed wild-type and mutant γ2 subunit BACs containing the endogenous hGABRG2 promoter in transgenic mice. Wild-type and mutant GABRG2 mRNA splicing patterns were determined in both BAC-transfected HEK293T cells and transgenic mouse brain, and in both, the mutation abolished intron 6 splicing at the donor site, activated a cryptic splice site, generated partial intron 6 retention, and produced a frameshift in exon 7 that created a premature translation termination codon (PTC). The resultant mutant mRNA was either degraded partially by nonsense-mediated mRNA decay or translated to a stable, truncated subunit (the γ2-PTC subunit) containing the first six GABRG2 exons and a novel frameshifted 29 aa C-terminal tail. The γ2-PTC subunit was homologous to the mollusk AChBP (acetylcholine binding protein) but was not secreted from cells. It was retained in the ER and not expressed on the surface membrane, but it did oligomerize with α1 and ß2 subunits. These results suggested that the GABRG2 mutation, IVS6+2T→G, reduced surface αßγ2 receptor levels, thus reducing GABAergic inhibition, by reducing GABRG2 transcript level and producing a stable, nonfunctional truncated subunit that had a dominant-negative effect on αßγ2 receptor assembly.


Assuntos
Regulação da Expressão Gênica/genética , Íntrons/genética , Mutação/genética , Degradação do RNAm Mediada por Códon sem Sentido/genética , Subunidades Proteicas/metabolismo , Splicing de RNA/genética , Receptores de GABA-A/genética , Análise de Variância , Animais , Encéfalo/metabolismo , Linhagem Celular Transformada , Células Cultivadas , Córtex Cerebral/citologia , Cromossomos Artificiais Bacterianos/genética , Códon sem Sentido/genética , Embrião de Mamíferos , Citometria de Fluxo , Humanos , Imunoprecipitação , Potenciais da Membrana/efeitos dos fármacos , Potenciais da Membrana/genética , Potenciais da Membrana/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Microscopia Confocal , Modelos Moleculares , Neurônios/efeitos dos fármacos , Neurônios/fisiologia , Técnicas de Patch-Clamp , Transporte Proteico/genética , RNA Mensageiro/metabolismo , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Ratos , Ratos Sprague-Dawley , Transfecção/métodos , Ácido gama-Aminobutírico/farmacologia
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