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1.
Chemistry ; 30(33): e202400816, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38613472

RESUMO

Near-Infrared-II (NIR-II) spans wavelengths between 1,000 to 1,700 nanometers, featuring deep tissue penetration and reduced tissue scattering and absorption characteristics, providing robust support for cancer treatment and tumor imaging research. This review explores the utilization of activatable NIR-II photodiagnosis and phototherapy based on tumor microenvironments (e. g., reactive oxygen species, pH, glutathione, hypoxia) and external stimulation (e. g., laser, ultrasound, photothermal) for precise tumor treatment and imaging. Special emphasis is placed on the advancements and advantages of activatable NIR-II nanomedicines in novel therapeutic modalities like photodynamic therapy, photothermal therapy, and photoacoustic imaging. This encompasses achieving deep tumor penetration, real-time monitoring of the treatment process, and obtaining high-resolution, high signal-to-noise ratio images even at low material concentrations. Lastly, from a clinical perspective, the challenges faced by activatable NIR-II phototherapy are discussed, alongside potential strategies to overcome these hurdles.


Assuntos
Raios Infravermelhos , Nanoestruturas , Neoplasias , Humanos , Nanoestruturas/química , Nanoestruturas/uso terapêutico , Neoplasias/diagnóstico por imagem , Neoplasias/terapia , Fototerapia/métodos , Animais , Microambiente Tumoral , Fotoquimioterapia , Técnicas Fotoacústicas/métodos , Espécies Reativas de Oxigênio/metabolismo , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/uso terapêutico
2.
Bioconjug Chem ; 33(1): 67-86, 2022 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-34995076

RESUMO

Photoacoustic imaging (PAI) has attracted great attention in the diagnosis and treatment of diseases due to its noninvasive properties. Especially in the second near-infrared (NIR-II) window, PAI can effectively avoid the interference of tissue spontaneous fluorescence and light scattering, and obtain high resolution images with deeper penetration depth. Because of its ideal spectral absorption and high conversion efficiency, NIR-II PA contrast agents overcome the absorption or emission of NIR-II light by endogenous biomolecules. In recent years, a series of NIR-II PA contrast agents have been developed to improve the performance of PAI in disease diagnosis and treatment. In this paper, the research progress of NIR-II PA contrast agents and their applications in biomedicine are reviewed. PA contrast agents are classified according to their composition, including inorganic contrast agents, organic contrast agents, and hybrid organic-inorganic contrast agents. The applications of NIR-II PA contrast agents in medical imaging are described, such as cancer imaging, inflammation detection, brain disease imaging, blood related disease imaging, and other biomedical application. Finally, the research prospects and breakthrough of NIR-II PA contrast agents are discussed.


Assuntos
Técnicas Fotoacústicas
3.
Opt Express ; 29(24): 40397-40405, 2021 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-34809381

RESUMO

In this paper, we investigated the impact of the linewidth of a QCW pulsed sodium laser on the brightness performance of a generating sodium laser guide star by using the numerical simulation tool PRS. We compared the field test results with the simulation results for two TIPC's 30W class sodium guide star lasers and found the results are in good agreement which proves the tool can be used for prediction. Then, we used the tool to study the influence of D2b repumping and different linewidths from 10MHz to 1GHz on the coupling efficiency and the photon return flux. For the TIPC's QCW pulsed solid-state laser, when the on-sky power density is 1 W/m2, the coupling efficiency is 79.6 (photons/s/W/(atoms/m2)) without D2b repumping, however, the value is up to 213.3 (photons/s/W/(atoms/m2)) with 15% D2b enabled and is increased by 168% than the value without D2b; when the power density reaches 10 W/m2, the coupling efficiencies without D2b and with 15% D2b are 66.6 and 233.6 (photons/s/W/(atoms/m2)), respectively. The results show that for the QCW pulsed laser, D2b repumping is necessary. With D2b enabled, if the spectral linewidth is too wide or too narrow, the photon return flux will be adversely affected. The return flux of 60MHz is 52.5% higher than that of 1GHz, while the return flux of 300MHz is 37.8% higher than that of 10 MHz when the laser power is 100W.

4.
J Integr Plant Biol ; 63(4): 787-802, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33433058

RESUMO

Trimethylated histone H3 lysine 27 (H3K27me3) is a repressive histone marker that regulates a variety of developmental processes, including those that determine flowering time. However, relatively little is known about the mechanism of how H3K27me3 is recognized to regulate transcription. Here, we identified BAH domain-containing transcriptional regulator 1 (BDT1) as an H3K27me3 reader. BDT1 is responsible for preventing flowering by suppressing the expression of flowering genes. Mutation of the H3K27me3 recognition sites in the BAH domain disrupted the binding of BDT1 to H3K27me3, leading to de-repression of H3K27me3-enriched flowering genes and an early-flowering phenotype. We also found that BDT1 interacts with a family of PHD finger-containing proteins, which we named PHD1-6, and with CPL2, a Pol II carboxyl terminal domain (CTD) phosphatase responsible for transcriptional repression. Pull-down assays showed that the PHD finger-containing proteins can enhance the binding of BDT1 to the H3K27me3 peptide. Mutations in all of the PHD genes caused increased expression of flowering genes and an early-flowering phenotype. This study suggests that the binding of BDT1 to the H3K27me3 peptide, which is enhanced by PHD proteins, is critical for preventing early flowering.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Flores/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Flores/genética , Regulação da Expressão Gênica de Plantas/genética , Regulação da Expressão Gênica de Plantas/fisiologia , Mutação/genética
5.
Cereb Cortex ; 28(11): 3753-3763, 2018 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-28968654

RESUMO

The medial prefrontal cortex (mPFC) is closely involved in many higher-order cognitive functions, including learning to associate temporally discontiguous events (called temporal associative learning). However, direct evidence for the role of mPFC and the neural pathway underlying modulation of temporal associative motor learning is sparse. Here, we show that optogenetic inhibition of the mPFC or its axon terminals at the pontine nuclei (PN) during trace intervals or whole trial period significantly impaired the trace eyeblink conditioning (TEC), but had no significant effects on TEC during the conditioned stimulus or intertrial interval period. Our results suggest that activities associated with the mPFC-PN projection during trace intervals is crucial for trace associative motor learning. This finding is of great importance in understanding the mechanisms and the relevant neural pathways underlying mPFC modulation of temporal associative motor learning.


Assuntos
Condicionamento Palpebral/fisiologia , Ponte/fisiologia , Córtex Pré-Frontal/fisiologia , Animais , Axônios/fisiologia , Masculino , Vias Neurais/fisiologia , Optogenética , Ratos Sprague-Dawley , Fatores de Tempo
6.
Cereb Cortex ; 28(3): 880-893, 2018 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-28077515

RESUMO

Diverse and powerful mechanisms have evolved to enable organisms to modulate learning and memory under a variety of survival conditions. Cumulative evidence has shown that the prefrontal cortex (PFC) is closely involved in many higher-order cognitive functions. However, when and how the medial PFC (mPFC) modulates associative motor learning remains largely unknown. Here, we show that delay eyeblink conditioning (DEC) with the weak conditioned stimulus (wCS) but not the strong CS (sCS) elicited a significant increase in the levels of c-Fos expression in caudal mPFC. Both optogenetic inhibition and activation of the bilateral caudal mPFC, or its axon terminals at the pontine nucleus (PN) contralateral to the training eye, significantly impaired the acquisition, recent and remote retrieval of DEC with the wCS but not the sCS. However, direct optogenetic activation of the contralateral PN had no significant effect on the acquisition, recent and remote retrieval of DEC. These results are of great importance in understanding the elusive role of the mPFC and its projection to PN in subserving the associative motor learning under suboptimal learning cue.


Assuntos
Aprendizagem por Associação/fisiologia , Sinais (Psicologia) , Atividade Motora/fisiologia , Vias Neurais/fisiologia , Tegmento Pontino/fisiologia , Córtex Pré-Frontal/fisiologia , Animais , Proteínas de Ligação ao Cálcio , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Condicionamento Clássico , Potenciais Pós-Sinápticos Excitadores/genética , Agonistas de Receptores de GABA-A/farmacologia , Proteínas Luminescentes/genética , Proteínas Luminescentes/metabolismo , Masculino , Muscimol/farmacologia , Optogenética , Farmacogenética , Ratos , Ratos Sprague-Dawley , Transdução Genética
7.
Chin J Physiol ; 62(2): 80-85, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31243178

RESUMO

Prepulse inhibition (PPI) and habituation of the acoustic startle response (ASR) are considered to be effective neurobiological measures of sensorimotor gating and information processing. The deficit of PPI and habituation of ASR has been proposed to be candidate endophenotypes of schizophrenia spectrum disorders. However, there has been little information on PPI and ASR measures in Chinese. The present study aimed to provide more information about the characteristics of PPI and ASR in young healthy Chinese and investigate their sensitivity to experimental parameters and characteristics of population. In this study, we examined the PPI and habituation of ASR in 41 young healthy adults (21 males and 20 females), using an acoustic startle stimulus of 115 dB and a prepulse of 75 dB at a lead interval (LI) of 60 ms and 120 ms, respectively. The behavioral performance demonstrated that the PPI and habituation of ASR in all the young participants were robust. The significant difference was not observed in PPI and habituation between male and female. The block effect on PPI was significant; PPI reduces with increasing training. Latency facilitation was observed under prepulse conditions, with a significant effect of LI. Compared to previous studies in Caucasians, Chinese in this study shows a higher habituation and PPI. In conclusion, this research provides more data of behavioral characteristics of PPI and ASR in young healthy Chinese. Chinese in this study shows a higher habituation and PPI than Caucasians in previous studies.


Assuntos
Inibição Pré-Pulso , Esquizofrenia , Estimulação Acústica , Povo Asiático , Feminino , Humanos , Masculino , Reflexo de Sobressalto
8.
Opt Lett ; 41(8): 1732-5, 2016 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-27082331

RESUMO

A 65 W quasi-continuous-wave microsecond-pulse solid-state sodium beacon laser tuned to the sodium D2a line has been developed with a linewidth of 0.3 GHz, beam quality of M2=1.38, and pulse width of 120 µs at a repetition rate of 500 Hz by sum-frequency mixing 1319 and 1064 nm diode-pumped Nd:YAG master-oscillator power-amplifier systems. The laser wavelength stability is less than ±0.15 GHz through feedback controlling. The laser spiking due to relaxation oscillations is suppressed by inserting frequency doublers in both 1319 and 1064 nm oscillators. Sodium D2b re-pumping is accomplished by tuning the frequency of the electro-optic modulator with the right D2a-D2b offset. A bright sodium laser guide star with a photon return of 1820 photons/cm2/s was achieved with the laser system when a 32 W circular polarized beam was projected to the sky during our field test at the Xinglong Observatory.

9.
Am J Ther ; 23(3): e926-9, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-24987944

RESUMO

Distal bone metastases from rectal cancer are uncommon. Our case report is from a patient with rectal carcinoma who presented with symptomatic middle finger metastases, and we describe the clinical characteristics of this presentation and the treatment provided. Metastases in bone tissues are a sign of a grave prognostic outcome due to the association of this with advanced terminal disease. Palliative treatment for symptom relief is the only option in this situation.


Assuntos
Adenocarcinoma/patologia , Neoplasias Ósseas/secundário , Neoplasias Retais/patologia , Adenocarcinoma/terapia , Neoplasias Ósseas/terapia , Terapia Combinada , Feminino , Falanges dos Dedos da Mão/patologia , Humanos , Pessoa de Meia-Idade , Neoplasias Retais/terapia
10.
Clin Lab ; 62(5): 807-14, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27349005

RESUMO

BACKGROUND: Even within the reference range, thyrotropin (TSH) levels were found to be positively associated with the risk of cardiovascular disease (CVD). However, the underlying mechanism of TSH remains ambiguous. This study investigated the association of TSH with cardiovascular risk factors among healthy Chinese subjects and subjects with unsuspected subclinical hypothyroidism (SCH). METHODS: A total of 741 subjects were included in this cross-sectional study. The subjects were grouped into four, including tertile groups for the TSH reference range and an SCH group based on the TSH level. All the participants underwent physical examination and fasting blood analyses to determine the levels of TSH, free thyroxine, free triiodothyronine, plasma glucose, triglycerides (TG), total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), apolipoprotein A1, apolipoprotein B (ApoB), lipoprotein(a), homocysteine (Hcy), and high sensitivity C-reactive protein (hs-CRP). RESULTS: The TSH subgroups exhibited a significant increasing trend in terms of LDL-C, ApoB, and Hcy levels (p = 0.01, p < 0.01, and p = 0.01, respectively), whereas the HDL-C levels exhibited a decreasing trend (p = 0.03). After adjusting for gender, age, and smoking status, the TSH levels were found to be positively correlated with body mass index, waist circumference, diastolic blood pressure (DBP), and TG, TC, LDL-C, ApoB, Hcy, and hs-CRP levels (p < 0.05 for all), but negatively correlated with the HDL-C levels (p < 0.01). Multiple linear regression analysis showed that the TSH levels were independently positively associated with the female gender (ß = 0.21, p < 0.01), DBP (ß = 0.14, ß = 0.01), and Hcy levels (ß = 0.10, p = 0.01), and negatively associated with the HDL-C (ß = -0.11, p = 0.01) and FT4 levels (ß = -0.15, p < 0.01). CONCLUSIONS: The TSH levels were independently associated with several cardiovascular risk factors in an apparently healthy Chinese population, and thus may increase the risk of CVD.


Assuntos
Doenças Cardiovasculares/etiologia , Hipotireoidismo/complicações , Tireotropina/sangue , Adulto , Doenças Cardiovasculares/sangue , HDL-Colesterol/sangue , Estudos Transversais , Feminino , Humanos , Hipotireoidismo/sangue , Masculino , Pessoa de Meia-Idade , Fatores de Risco
11.
J Sep Sci ; 39(4): 648-54, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26447826

RESUMO

Aqueous two-phase systems, based on the use of natural quaternary ammonium compounds, were developed to establish a benign biotechnological route for efficient protein separation. In this study, aqueous two-phase systems of two natural resources betaine and choline with polyethyleneglycol (PEG400/600) or inorganic salts (K2 HPO4 /K3 PO4 ) were formed. It was shown that in the K2 HPO4 -containing aqueous two-phase system, hydrophobic interactions were an important driving force of protein partitioning, while protein size played a vital role in aqueous two-phase systems that contained polyethylene glycol. An extraction efficiency of more than 90% for bovine serum albumin in the betaine/K2 HPO4 aqueous two-phase system can be obtained, and this betaine-based aqueous two-phase system provided a gentle and stable environment for the protein. In addition, after investigation of the cluster phenomenon in the betaine/K2 HPO4 aqueous two-phase systems, it was suggested that this phenomenon also played a significant role for protein extraction in this system. The development of aqueous two-phase systems based on natural quaternary ammonium compounds not only provided an effective and greener method of aqueous two-phase system to meet the requirements of green chemistry but also may help to solve the mystery of the compartmentalization of biomolecules in cells.


Assuntos
Fracionamento Químico/métodos , Proteínas/química , Compostos de Amônio Quaternário/química , Compostos de Amônio/química , Animais , Betaína/química , Bovinos , Colina/química , Dicroísmo Circular , Química Verde , Interações Hidrofóbicas e Hidrofílicas , Luz , Substâncias Macromoleculares/química , Muramidase/química , Ovalbumina/química , Polietilenoglicóis/química , Proteínas/isolamento & purificação , Sais/química , Espalhamento de Radiação , Soroalbumina Bovina/química , Tripsina/química , Água
12.
Lipids Health Dis ; 15: 53, 2016 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-26965314

RESUMO

Non-alcoholic fatty liver disease (NAFLD) is a common chronic liver disease which represents a wide spectrum of hepatic damage. Several studies have reported that NAFLD is a strong independent risk factor for coronary artery disease (CAD). And patients with NAFLD are at higher risk and suggested undergoperiodic cardiovascular risk assessment. Cardiovascular disease (CVD) is responsible for the main cause of death in patients with NAFLD, and is mostly influenced by genetic factors. Both NAFLD and CAD are heterogeneous disease. Common pathways involved in the pathogenesis of NAFLD and CAD includes insulin resistance (IR), atherogenic dyslipidemia, subclinical inflammation, oxidative stress, etc. Genomic characteristics of these two diseases have been widely studied, further research about the association of these two diseases draws attention. The gene polymorphisms of adiponectin-encoding gene (ADIPOQ), leptin receptor (LEPR), apolipoprotein C3 (APOC3), peroxisome proliferator-activated receptors (PPAR), sterol regulatory elementbinding proteins (SREBP), transmembrane 6 superfamily member 2 (TM6SF2), microsomal triglyceride transfer protein (MTTP), tumor necrosis factors-alpha (TNF-α) and manganese superoxide dismutase (MnSOD) have been reported to be related to NAFLD and CAD. In this review, we aimed to provide an overview of recent insights into the genetic basis of NAFLD and CAD.


Assuntos
Doença da Artéria Coronariana/genética , Hepatopatia Gordurosa não Alcoólica/genética , Polimorfismo Genético , Adiponectina/genética , Apolipoproteína C-III/genética , Proteínas de Transporte/genética , Humanos , Proteínas de Membrana/genética , Receptores Ativados por Proliferador de Peroxissomo/genética , Receptores para Leptina/genética , Proteínas de Ligação a Elemento Regulador de Esterol/genética , Superóxido Dismutase/genética , Fator de Necrose Tumoral alfa/genética
13.
J Med Virol ; 87(3): 446-50, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25164987

RESUMO

Hepatitis E infection, caused by the hepatitis E virus (HEV), is an important global public health concern, with particularly high mortality in pregnant women. China is generally judged to be an HEV-endemic area, but epidemiological data for HEV among pregnant women are limited. Between June 2011 and July 2013, a case-control study was conducted to estimate the seroprevalence and potential risk factors associated with the acquisition of HEV infection by pregnant women in China. Nine-hundred and ninety pregnant women who visited hospitals for antenatal follow-up or medication in Qingdao and Weihai and 965 control subjects matched by age, gender and residence were examined for the presence of anti-HEV IgG and IgM antibodies by enzyme immunoassays. Socio-demographic and behavioral characteristics from the study subjects were obtained. The overall prevalence of anti-HEV IgG in all 1,955 samples was 20.7%. In pregnant women, 16.2% of samples were anti-HEV IgG positive whereas, in control subjects 25.3% of samples were anti-HEV IgG positive, (P < 0.01). For anti-HEV IgM detection, 62 (3.2%) of the 1,955 serum samples were positive and the seroprevalence in pregnant women and control subjects was 2.6% and 3.6%, respectively. Age, contact with cats, contact with pigs and exposure to soil were found to be associated with HEV infection. These findings demonstrated the high prevalence of HEV and the considerable potential for the transmission of HEV infection in pregnant women in China.


Assuntos
Anticorpos Anti-Hepatite/sangue , Vírus da Hepatite E/imunologia , Hepatite E/epidemiologia , Complicações Infecciosas na Gravidez/epidemiologia , Adolescente , Adulto , Animais , Estudos de Casos e Controles , China/epidemiologia , Exposição Ambiental , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Animais de Estimação , Gravidez , Gestantes , Fatores de Risco , Estudos Soroepidemiológicos , Adulto Jovem
14.
Endocr Res ; 40(2): 74-8, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25330278

RESUMO

OBJECTIVES: This study was designed to test the hypothesis that normal thyroid function is associated with non-alcoholic fatty liver disease (NAFLD) in euthyroid general subjects. METHODS: A total of 739 euthyroid subjects were enrolled in this cross-sectional study. Using ultrasound, a diagnosis of NAFLD was made in subjects without a history of excessive alcohol consumption or liver diseases. Fasting serum samples were collected for determining thyroid function [thyroid-stimulating hormone (TSH), free thyroxine (FT4), and free triiodothyronine (FT3) levels] and other biochemical parameters. RESULTS: Among the enrolled subjects, 196 (26.5%) satisfied the diagnostic criteria for NAFLD. Subjects with NAFLD had significantly higher TSH levels and lower FT4 levels than those without NAFLD (p < 0.01 for both). NAFLD prevalence increased gradually with increasing quartiles of TSH levels and decreasing quartiles of FT4 levels. After adjustment for gender and age, TSH levels were found to correlate positively with body mass index (BMI), waist circumference (WC), and LDL-cholesterol levels (p < 0.05 for all) and negatively with HDL-cholesterol levels (p < 0.01). FT4 levels correlated negatively with both BMI and WC (p < 0.05 for both). Multiple logistic regression analysis showed that TSH and FT4 levels were independent risk factors for NAFLD [odds ratio (OR): 2.21, 95% confidence interval (CI): 1.21-4.02, p = 0.01, for TSH levels; OR: 0.39, 95% CI: 0.17-0.87, p = 0.02, for FT4 levels]. CONCLUSION: Our findings suggest that serum FT4 and TSH levels, even those within the reference range, are associated with NAFLD in the general population, independent of known metabolic risk factors.


Assuntos
Hepatopatia Gordurosa não Alcoólica/sangue , Hepatopatia Gordurosa não Alcoólica/fisiopatologia , Glândula Tireoide/fisiopatologia , Adulto , Estudos Transversais , Feminino , Humanos , Masculino , Síndrome Metabólica/sangue , Síndrome Metabólica/fisiopatologia , Pessoa de Meia-Idade , Hepatopatia Gordurosa não Alcoólica/diagnóstico por imagem , Testes de Função Tireóidea , Tireotropina/sangue , Tiroxina/sangue , Tri-Iodotironina/sangue , Ultrassonografia
15.
Bioprocess Biosyst Eng ; 38(11): 2053-61, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26210852

RESUMO

In this study, enzymatic selective esterification of oleic acid with glycerol based on deep eutectic solvent acting as substrate and solvent was studied. As choline chloride (ChCl) or betaine can effectively change the chemical reaction characteristics of glycerol when they are mixed with a certain molar ratio of glycerol, several factors crucial to the lipase catalytic esterification of glycerol with oleic acid was investigated. Results showed that, betaine had more moderate effects than ChCl on the lipase, and water content had an important influence of the esterification and the enzyme selectivity. Significant changes of the glyceride compositions and enzyme selectivity were found in ChCl adding system compared with pure glycerol system; optimum accumulation of DAG especially 1,3-DAG because of the eutectic effect of ChCl was found in this system. Furthermore, in a model 1,3-DAG esterification synthesis system catalyzed by Novozym 435, high content (42.9 mol%) of the 1,3-DAG could be obtained in ChCl adding system within 1 h.


Assuntos
Diglicerídeos/síntese química , Lipase/química , Modelos Químicos , Diglicerídeos/química , Enzimas Imobilizadas , Esterificação , Proteínas Fúngicas , Solventes/química
16.
Cerebellum ; 13(1): 64-78, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24013852

RESUMO

Behavioral studies have demonstrated that both medial prefrontal cortex (mPFC) and cerebellum play critical roles in trace eyeblink conditioning. However, little is known regarding the mechanism by which the two brain regions interact. By use of electrical stimulation of the caudal mPFC as a conditioned stimulus, we show evidence that persistent outputs from the mPFC to cerebellum are necessary and sufficient for the acquisition and expression of a trace conditioned response (CR)-like response. Specifically, the persistent outputs of caudal mPFC are relayed to the cerebellum via the rostral part of lateral pontine nuclei. Moreover, interfering with persistent activity by blockade of the muscarinic Ach receptor in the caudal mPFC impairs the expression of learned trace CRs. These results suggest an important way for the caudal mPFC to interact with the cerebellum during associative motor learning.


Assuntos
Cerebelo/fisiologia , Condicionamento Clássico/fisiologia , Córtex Pré-Frontal/fisiologia , 2-Amino-5-fosfonovalerato/farmacologia , Animais , Aprendizagem por Associação/efeitos dos fármacos , Aprendizagem por Associação/fisiologia , Piscadela/efeitos dos fármacos , Piscadela/fisiologia , Cerebelo/efeitos dos fármacos , Condicionamento Clássico/efeitos dos fármacos , Antagonistas de Aminoácidos Excitatórios/farmacologia , Extinção Psicológica/efeitos dos fármacos , Extinção Psicológica/fisiologia , Agonistas de Receptores de GABA-A/farmacologia , Cobaias , Masculino , Antagonistas Muscarínicos/farmacologia , Muscimol/farmacologia , Vias Neurais/efeitos dos fármacos , Vias Neurais/fisiologia , Ponte/efeitos dos fármacos , Ponte/fisiologia , Córtex Pré-Frontal/efeitos dos fármacos , Receptores de GABA-A/metabolismo , Receptores Muscarínicos/metabolismo , Reflexo de Sobressalto/efeitos dos fármacos , Reflexo de Sobressalto/fisiologia , Escopolamina/farmacologia
17.
Int J Biol Macromol ; : 133411, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38945722

RESUMO

Preparing bio-based air filtration membrane through green electrospinning strategy is a vital approach to alleviating environmental and energy crises. However, the development of related biomaterials and method for regulating membrane structure are still lacking. In this study, ethyl cellulose (EC) bimodal nanofibrous membrane was prepared by electrospinning using ethanol and water as solvents to achieve high-performance air filtration. A new strategy for bimodal fiber molding based on molecular weight modulation was proposed. The EC polymer chains with medium molecular weights were subject to the highest degree of inhomogeneity of solvent intrusion, and there were significant differences in viscous forces "microscopically", leading to the formation of bimodal structure by inhomogeneous stretching of the jet. The well-defined bimodal structure endowed EC membrane with excellent air filtration performance. The filtration efficiency for PM0.3, pressure drop, quality factor were 99.11 %, 42.2 Pa, and 0.112 Pa-1, respectively. Compared to the commonly used zein, EC cost just 12.77 %, and its solution had a 50 % longer shelf life, making it a more desirable biomaterial. This work will facilitate the application of more biomaterials in air filtration, promote the green fabrication of high-performance air filtration membranes, and realize sustainable development.

18.
Behav Brain Res ; 468: 114999, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38615978

RESUMO

Itch is one of the most common clinical symptoms in patients with diseases of the skin, liver, or kidney, and it strongly triggers aversive emotion and scratching behavior. Previous studies have confirmed the role of the prelimbic cortex (Prl) and the nucleus accumbens core (NAcC), which are reward and motivation regulatory centers, in the regulation of itch. However, it is currently unclear whether the Prl-NAcC projection, an important pathway connecting these two brain regions, is involved in the regulation of itch and its associated negative emotions. In this study, rat models of acute neck and cheek itch were established by subcutaneous injection of 5-HT, compound 48/80, or chloroquine. Immunofluorescence experiments determined that the number of c-Fos-immunopositive neurons in the Prl increased during acute itch. Chemogenetic inhibition of Prl glutamatergic neurons or Prl-NAcC glutamatergic projections can inhibit both histaminergic and nonhistaminergic itch-scratching behaviors and rectify the itch-related conditioned place aversion (CPA) behavior associated with nonhistaminergic itch. The Prl-NAcC projection may play an important role in the positive regulation of itch-scratching behavior by mediating the negative emotions related to itch.


Assuntos
Vias Neurais , Núcleo Accumbens , Prurido , Ratos Sprague-Dawley , Animais , Prurido/fisiopatologia , Núcleo Accumbens/fisiologia , Núcleo Accumbens/efeitos dos fármacos , Masculino , Ratos , Vias Neurais/fisiologia , Vias Neurais/fisiopatologia , Modelos Animais de Doenças , Neurônios/fisiologia , Aprendizagem da Esquiva/fisiologia , Comportamento Animal/fisiologia , Córtex Pré-Frontal/fisiologia , Córtex Pré-Frontal/metabolismo , Proteínas Proto-Oncogênicas c-fos/metabolismo
19.
Phys Chem Chem Phys ; 15(21): 8186-98, 2013 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-23608819

RESUMO

We report a new family of M12N12 (M = Al and Ga) cluster-assembled low-density materials with distinguished structures and properties based on state-of-the-art first-principles calculations. Specifically, the thermodynamic stability of the sodalite cage M12N12, with Th symmetry and a large HOMO-LUMO gap, is firstly proved using a first-principles molecular dynamics (FPMD) study. We consider this novel structure as a building block to construct new cluster-assembled materials. On the basis of the interaction of the cages with each other, eight new low-density nanoporous phases have been characterized, some of which with high stability are even more stable than experimentally synthesized MN phases. The intrinsic higher flexibilities (lower bulk moduli) and porous characteristics (the pore size: from 0.360 to 0.952 nm for AlN, 0.381 to 0.982 nm for GaN) of these phases should make them extremely promising for molecular sieving, gas storage, and particularly, atomic transport, control and purification applications. Furthermore, these new materials can not only retain the structural characteristics of the building block, but also preserve its electronic properties of wide-energy gap, with an indirect or a direct band gap of 1.038-2.640 eV. Our results may be feasible for extending the range of properties and applications of the corresponding MN compound.

20.
J Craniofac Surg ; 24(3): 805-8, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23714884

RESUMO

Distraction osteogenesis (DO) has been a widely applied technique in orthopedics and craniofacial surgery. However, the exact molecular mechanism by which the mechanical stimulus is translated into biological signals is still poorly understood. In this study, we examined and compared the expression of stromal cell-derived factor-1 (SDF-1) during mandibular distraction osteogenesis and fracture in rats, respectively. Forty-eight male Sprague-Dawley rats were divided into 2 groups and received unilateral distraction osteogenesis and rigid internal fixation, respectively, after the osteotomy on the right mandible. The harvested mandibles were examined radiographically, histologically, and immunohistochemically. We found that the expression of SDF-1 was mainly detected in the osteoblasts and blood vessels, and there were more intensive expression of SDF-1 in DO zones than in bone fracture zones. The quantitative analysis by enzyme-linked immunosorbent assay showed that SDF-1 reached a greater peak and maintained a longer period of up-regulation in DO than in fracture healing (P < 0.05). These results suggest that the distraction procedure markedly promotes the high expression of SDF-1 which facilitates the induction of bone formation during DO.


Assuntos
Regeneração Óssea/fisiologia , Quimiocina CXCL12/metabolismo , Consolidação da Fratura/fisiologia , Fraturas Mandibulares , Osteogênese por Distração , Animais , Modelos Animais de Doenças , Ensaio de Imunoadsorção Enzimática , Masculino , Fraturas Mandibulares/metabolismo , Fraturas Mandibulares/cirurgia , Osteoblastos/metabolismo , Osteogênese por Distração/métodos , Ratos , Ratos Sprague-Dawley , Regulação para Cima
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