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1.
Int J Mol Sci ; 24(8)2023 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-37108197

RESUMO

Casein kinase 1α (CK1α) is present in multiple cellular organelles and plays various roles in regulating neuroendocrine metabolism. Herein, we investigated the underlying function and mechanisms of CK1α-regulated thyrotropin (thyroid-stimulating hormone (TSH)) synthesis in a murine model. Immunohistochemistry and immunofluorescence staining were performed to detect CK1α expression in murine pituitary tissue and its localization to specific cell types. Tshb mRNA expression in anterior pituitary was detected using real-time and radioimmunoassay techniques after CK1α activity was promoted and inhibited in vivo and in vitro. Relationships among TRH/L-T4, CK1α, and TSH were analyzed with TRH and L-T4 treatment, as well as thyroidectomy, in vivo. In mice, CK1α was expressed at higher levels in the pituitary gland tissue than in the thyroid, adrenal gland, or liver. However, inhibiting endogenous CK1α activity in the anterior pituitary and primary pituitary cells significantly increased TSH expression and attenuated the inhibitory effect of L-T4 on TSH. In contrast, CK1α activation weakened TSH stimulation by thyrotropin-releasing hormone (TRH) by suppressing protein kinase C (PKC)/extracellular signal-regulated kinase (ERK)/cAMP response element binding (CREB) signaling. CK1α, as a negative regulator, mediates TRH and L-T4 upstream signaling by targeting PKC, thus affecting TSH expression and downregulating ERK1/2 phosphorylation and CREB transcriptional activity.


Assuntos
Caseína Quinases , MAP Quinases Reguladas por Sinal Extracelular , Tireotropina , Animais , Camundongos , Caseína Quinases/metabolismo , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Hipófise/metabolismo , Tireotropina/metabolismo , Hormônio Liberador de Tireotropina/metabolismo , Tiroxina/farmacologia
2.
Nanotechnology ; 33(50)2022 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-36049467

RESUMO

Ultra-high frequency (UHF) radio frequency identification (RFID) tags need to be attached or embedded to objects in various environments to achieve non-contact automatic identification. Graphene shows unique electrical and optical properties, which makes it become a promising material for radio frequency devices. In this paper, the transparent UHF RFID tags were fabricated based on graphene films with different number of stacked layers prepared by chemical vapor deposition (CVD). Through structural design, parameter optimization and experimental measurements, the reading distance of the transparent RFID tags was tested and compared. As the graphene film stacked layers increased, the reading distance of graphene-based RFID tags was farther. The UHF RFID tag based on the CVD-grown graphene with the light transmittance of 88% reached the maximum reading distance of 2.78 m in the frequency range of 860-960 MHz. In addition, the reading distance of graphene-based RFID tags at different bending angles and cycles was measured. The results reveal transparent graphene-based RFID tags have good flexibility and stability and can be used in flexible transparent devices.

3.
Materials (Basel) ; 16(3)2023 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-36770126

RESUMO

It is significantly important to modulate the electrical properties of graphene films through doping for building desired electronic devices. One of the effective doping methods is the chemical vapor deposition (CVD) of graphene films with heteroatom doping during the process, but this usually results in nitrogen-doped graphene with low doping levels, high defect density, and low carrier mobility. In this work, we developed a novel condensation-assisted CVD method for the synthesis of high-quality nitrogen-doped graphene (NG) films at low temperatures of 400 °C using solid 3,4,5-trichloropyridine as a carbon and nitrogen source. The condensation system was employed to reduce the volatilization of the solid source during the non-growth stage, which leads to a great improvement of quality of as-prepared NG films. Compared to the one synthesized using conventional CVD methods, the NG films synthesized using condensation-assisted CVD present extremely low defects with a ratio of from D- to G-peak intensity (ID/IG) in the Raman spectrum lower than 0.35. The corresponding total N content, graphitic nitrogen/total nitrogen ratio, and carrier mobility reach 3.2 at%, 67%, and 727 cm2V-1S-1, respectively. This improved condensation-assisted CVD method provides a facile and well-controlled approach for fabricating high-quality NG films, which would be very useful for building electronic devices with high electrical performance.

4.
Micromachines (Basel) ; 14(4)2023 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-37420978

RESUMO

Suspended graphene film is of great significance for building high-performance electrical devices. However, fabricating large-area suspended graphene film with good mechanical properties is still a challenge, especially for the chemical vapor deposition (CVD)-grown graphene films. In this work, the mechanical properties of suspended CVD-grown graphene film are investigated systematically for the first time. It is found that monolayer graphene film is hard to maintain on circular holes with a diameter of tens of micrometers, which can be improved greatly by increasing the layer of graphene films. The mechanical properties of CVD-grown multilayer graphene films suspended on a circular hole with a diameter of 70 µm can be increased by 20%, and multilayer graphene films prepared by layer-layer stacking process can be increased by up to 400% for the same size. The corresponding mechanism was also discussed in detail, which might pave the way for building high-performance electrical devices based on high-strength suspended graphene film.

5.
World J Gastroenterol ; 29(41): 5657-5667, 2023 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-38077156

RESUMO

BACKGROUND: Functional constipation (FC) and constipation-predominant irritable bowel syndrome (IBS-C) represent a spectrum of constipation disorders. However, the majority of previous clinical investigations have focused on Western populations, with limited data originating from China. AIM: To determine and compare the colorectal motility and psychiatric features of FC and IBS-C in an Eastern Chinese population. METHODS: Consecutive chronic constipation patients referred to our motility clinic from December 2019 to February 2023 were enrolled. FC and IBS-C diagnoses were established using ROME IV criteria, and patients underwent high-resolution anorectal manometry (ARM) and a colonic transmit test using the Sitz marker study. Constipation-related symptoms were obtained through questionnaires. Anxiety and depression were assessed by the Hamilton anxiety rating scale and the Hamilton Depression Rating Scale-21. The clinical characteristics and colorectal motility patterns of FC and IBS-C patients were compared. RESULTS: No significant differences in sex, age or abdominal discomfort symptoms were observed between IBS-C and FC patients (all P > 0.05). The proportion of IBS-C patients with delayed colonic transit was higher than that of patients with FC (36.63% vs 15.91%, P < 0.05), while rectosigmoid accumulation of radiopaque markers was more common in the FC group than in the IBS-C group (50% vs 26.73%, P < 0.05). Diverse proportions of these dyssynergic patterns were noted within both the FC and IBS-C groups by ARM. IBS-C patients were found to have a higher prevalence of depression than FC patients (66.30% vs 42.42%, P < 0.05). The scores for feelings of guilt, suicide, psychomotor agitation, diurnal variation, obsessive/compulsive disorder, hopelessness, self-abasedment and gastrointestinal symptoms were significantly higher in IBS-C patients than that in FC patients (P < 0.05). For IBS-C (χ2 = 5.438, P < 0.05) but not FC, patients with normal colon transit time were significantly more likely to have anxiety than those with slow colon transit time. For IBS-C patients but not FC patients, the threshold of first constant sensation, desire to defecate and sustained urgency were all weakly correlated with the degree of anxiety (r = 0.414, r = 0.404, and r = 0.418, respectively, P < 0.05). The proportion of patients with a low threshold of desire to defecate among IBS-C patients with depression was lower than that in those without depression (69.6% vs 41.9%, χ2 = 4.054, P < 0.05). CONCLUSION: Our findings highlight both overlapping and distinctive patterns of colon transit, dyssynergic patterns, anorectal sensation, psychological distress, and associations of psychiatric and colorectal motility characteristics in FC and IBS-C patients in an Eastern Chinese population, providing valuable insights into the pathophysiological underpinnings of these disorders.


Assuntos
Neoplasias Colorretais , Síndrome do Intestino Irritável , Humanos , Síndrome do Intestino Irritável/complicações , Síndrome do Intestino Irritável/diagnóstico , Síndrome do Intestino Irritável/epidemiologia , Trânsito Gastrointestinal/fisiologia , Constipação Intestinal/diagnóstico , Constipação Intestinal/epidemiologia
6.
Mar Environ Res ; 140: 422-432, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30055835

RESUMO

Rhizosphere microbial communities play an important role in mediating the decomposition of soil organic matter. Increased CO2 concentration may increase plant growth by stimulating photosynthesis or improving water use efficiency. However, possible eco-physiological influences of this greenhouse gas in mangrove plants are not well understood, especially how rhizosphere microbial communities respond to CO2 increase. We characterized the effect of elevated CO2 (eCO2) on rhizospheric microbial communities associated with the mangrove plant Kandelia candel for 20 weeks, eCO2 increased plant chlorophyll a levels and root microbial biomass. Operational taxonomic unit analysis revealed no significant effects of eCO2 on rhizospheric bacterial communities; however, some influence on archaeal community structure was observed, especially on the ammonia-oxidizing archaea. Principal component analysis showed that microbial biomass C, total nitrogen, C/N ratio, nitrate nitrogen, and salinity were the main factors structuring the microbial community. The relative contribution of environmental parameters to variability among samples was 31.0%. In addition, functional analysis by average well color development showed that carbon source utilization under eCO2 occurred in the order amino acids > carbohydrates > polymers > carboxylic acids > amines > phenolic acids; whereas, sugars, amino acids, and carboxylic acids were the preferred carbon sources in control groups. Differences in utilization ability of carbohydrates and amino acids resulted in changes in carbon metabolism between the two groups. Rhizosphere microbial communities appear to have some buffering ability in response to short-term (20 weeks) CO2 increase, during which the metabolic efficiency of carbon sources is changed. The results will help better understand the structural inflexibility and functional plasticity of the rhizosphere microbiome in mangrove plants facing a changing environment (such as global climate change).


Assuntos
Dióxido de Carbono/metabolismo , Microbiota , Rhizophoraceae/microbiologia , Rizosfera
7.
Genome Announc ; 3(6)2015 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-26659690

RESUMO

Aeromonas hydrophila strain KOR1, isolated from mangrove rhizosphere soil, has the ability to produce the quorum-sensing signal molecule. Here, we report the 4.78-Mb genome sequence of strain KOR1, and found its quorum-sensing encoding gene LuxR. The data will be crucial to understanding the quorum-sensing-dependent phenotypes of this bacterium.

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