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1.
BMC Med ; 22(1): 300, 2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-39020393

RESUMO

BACKGROUND: Multiple high doses of 131I therapy in patients with differentiated thyroid cancer (DTC) might disrupt the balance of gut microbiota and metabolites. This study aimed to investigate the alterations of intestinal bacteria and metabolism over two courses of 131I therapy, explore the interactions, and construct diagnostic models reflecting enteric microecology based on 131I therapy. METHODS: A total of 81 patients were recruited for the first 131I therapy (131I-1st), among whom 16 received a second course (131I-2nd) after half a year. Fecal samples were collected 1 day before (Pre-131I-1st/2nd) and 3 days after (Post-131I-1st/2nd) 131I therapy for microbiome (16S rRNA gene sequencing) and metabolomic (LC-MS/MS) analyses. RESULTS: A total of six microbial genera and 11 fecal metabolites enriched in three pathways were identified to show significant differences between Pre-131I-1st and other groups throughout the two courses of 131I treatment. In the Post-131I-1st group, the beneficial bacteria Bifidobacterium, Lachnoclostridium, uncultured_bacterium_f_Lachnospiraceae, and Lachnospiraceae_UCG004 were abundant and the radiation-sensitive pathways of linoleic acid (LA), arachidonic acid, and tryptophan metabolism were inhibited compared with the Pre-131I-1st group. Compared with the Pre-131I-1st group, the Pre-131I-2nd group exhibited a reduced diversity of flora and differentially expressed metabolites, with a low abundance of beneficial bacteria and dysregulated radiation-sensitive pathways. However, less significant differences in microbiota and metabolites were found between the Pre/Post-131I-2nd groups compared with those between the Pre/Post-131I-1st groups. A complex co-occurrence was observed between 6 genera and 11 metabolites, with Lachnoclostridium, Lachnospiraceae_UCG004, Escherichia-Shigella, and LA-related metabolites contributing the most. Furthermore, combined diagnostic models of charactered bacteria and metabolites answered well in the early, long-term, and dose-dependent responses for 131I therapy. CONCLUSIONS: Different stages of 131I therapy exert various effects on gut microecology, which play an essential role in regulating radiotoxicity and predicting the therapeutic response.


Assuntos
Fezes , Microbioma Gastrointestinal , Radioisótopos do Iodo , Neoplasias da Glândula Tireoide , Humanos , Microbioma Gastrointestinal/fisiologia , Neoplasias da Glândula Tireoide/radioterapia , Neoplasias da Glândula Tireoide/microbiologia , Masculino , Feminino , Pessoa de Meia-Idade , Adulto , Fezes/microbiologia , Idoso , RNA Ribossômico 16S/genética , Adulto Jovem
2.
Angew Chem Int Ed Engl ; : e202411396, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39010646

RESUMO

Electrochemical nitrate reduction method (NitRR) is a low-carbon, environmentally friendly, and efficient method for synthesizing ammonia, which has received widespread attention in recent years. Copper-based catalysts have a leading edge in nitrate reduction due to their good adsorption of *NO3. However, the formation of active hydrogen (*H) on Cu surfaces is difficult and insufficient, resulting in a large amount of the by-product NO2-. In this work, Pd single atoms suspended on the interlayer unsaturated bonds of CuO atoms formed due to dislocations (Pd-CuO) were prepared by low temperature treatment, and the Pd single atoms located on the dislocations were subjected to shear stress and the dynamic effect of support formation to promote the conversion of nitrate into ammonia. The catalysis had an ammonia yield of 4.2 mol.gcat-1. h-1, and a Faraday efficiency of 90% for ammonia production at -0.5 V vs. RHE. Electrochemical in-situ characterization and theoretical calculations indicate that the dynamic effects of Pd single atoms and carriers under shear stress obviously promote the production of active hydrogen, reduce the reaction energy barrier of the decision-making step for nitrate conversion to ammonia, further promote ammonia generation.

3.
Inorg Chem ; 62(30): 11990-12000, 2023 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-37462358

RESUMO

Electrochemical nitrogen reduction reaction (NRR) is a promising method for ammonia synthesis under ambient conditions. However, the NRR performance is limited to an extremely strong N≡N bond in N2 and the competing hydrogen evolution reaction. Introducing oxygen vacancies (OVs) has been considered as a forceful means to accelerate the sluggish NRR reaction kinetics. Herein, we reported the design of Fe-doped NiMoO4 catalysts for NRR. Fe doping can increase the amount of OVs in the catalyst and contribute to lattice strain enhancement, thereby leading to the improvement of the electron transport rate and catalytic active for NRR. In 0.1 M Na2SO4 solution, the 5% Fe-NiMoO4 catalyst achieves a NH3 yield rate of 15.36 µg h-1 mgcat.-1 and a Faradaic efficiency of 26.85% under -0.5 V versus RHE. Furthermore, the 5% Fe-NiMoO4 catalyst exhibits excellent stability (up to 13 h) during the reaction.

4.
Anal Bioanal Chem ; 415(10): 1841-1854, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36799979

RESUMO

Nowadays, screening for endometrial cancer (EC) primarily relies on clinical symptoms and imaging, which makes it difficult to detect early-stage disease. Here, we conducted a widely targeted lipidomic analysis of 38 human serum samples in a discovery set and 40 human serum samples in a validation set to profile the dysregulated lipid species and establish lipid biomarkers for early-stage EC. This comprehensive lipidomic determination of 616 serum lipids indicated significant differences between early-stage EC patients and healthy controls. Three phases of lipid biomarker investigation (discovery, validation, and determination of the lipid biomarker panel) were performed, which revealed the upregulation of some sphingolipid, glycerophospholipid, and glycerolipids and downregulation of some carnitine. Consistently, the perturbation of sphingolipid and glycerophospholipid metabolism was also observed from pathway enrichment analysis. Moreover, a lipid biomarker panel, including ursodeoxycholic acid, PC(O-14:0_20:4), and Cer(d18:1/18:0), was established. This panel was assessed as an effective diagnostic model to distinguish early-stage EC patients from healthy controls and atypical endometrial hyperplasia patients within the area under the receiver operating characteristic curve (AUC) reaching 0.903 and 0.928, respectively. In particular, the comparison results of the diagnostic efficacy indicated that the lipid biomarker panel was superior to clinically established indicators for EC diagnosis, including HE4, CA125, CA153, and CA199, suggesting that it could be used as an excellent supplementary method for the diagnosis of early-stage EC. In conclusion, we established a novel and non-invasive lipid biomarker for early-stage EC detection and these findings may provide new insight into the pathological mechanisms of EC.


Assuntos
Neoplasias do Endométrio , Espectrometria de Massas em Tandem , Feminino , Humanos , Biomarcadores Tumorais , Lipidômica , Cromatografia Líquida de Alta Pressão , Neoplasias do Endométrio/diagnóstico , Neoplasias do Endométrio/patologia , Lipídeos , Esfingolipídeos , Glicerofosfolipídeos
5.
Phytother Res ; 37(11): 5378-5393, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37589332

RESUMO

Epinodosin has shown antibacterial and antitumor biological characteristics in the documents. We found that Epinodosin has an effective inhibitory effect on esophageal squamous cell carcinoma (ESCC). However, the potential roles and mechanisms of Epinodosin in ESCC remain unclear. We performed many experiments to clarify the effect and mechanism of Epinodosin on ESCC. In this study, cell viability, invasion, migration, and apoptosis were determined by 3-(4,5-dimethyl-2-thiazolyl)-2,-diphenytetrazoliumromide (MTT), Transwell, and flow cytometry. The differentially expressed miRNAs were screened through RNA transcriptome sequencing. The expression levels of miRNA-143-3p and some proteins were measured by real-time polymerase chain reaction (PCR) and Western blot. The anticancer effects of Epinodosin in vivo were determined by a nude mouse model. Epinodosin suppressed cell proliferation/invasion/migration and induced ESCC cell apoptosis. Epinodosin remarkably affected the protein expression of mitogen-activated protein kinase (MAPK) signaling pathway. The animal experiments demonstrated that Epinodosin could attenuate the growth of ESCC tumors in nude mice. The expression of p53, Bim, and Bax was upregulated, while that of Bcl-2 was downregulated in tumor tissues. In conclusion, Epinodosin suppresses cell viability/invasion/migration, while induces ESCC cell apoptosis by mediating miRNA-143-3p and Bcl-2, and can markedly attenuate the growth of ESCC tumors in nude mice.


Assuntos
Carcinoma de Células Escamosas , Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , MicroRNAs , Animais , Camundongos , Carcinoma de Células Escamosas do Esôfago/tratamento farmacológico , Carcinoma de Células Escamosas do Esôfago/patologia , Carcinoma de Células Escamosas/tratamento farmacológico , Camundongos Nus , Neoplasias Esofágicas/tratamento farmacológico , MicroRNAs/genética , MicroRNAs/metabolismo , Proliferação de Células/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Regulação Neoplásica da Expressão Gênica
6.
Plant Dis ; 107(10): 3037-3050, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36890126

RESUMO

Among the most damaging diseases of rubber trees is anthracnose caused by the genus Colletotrichum, which leads to significant economic losses. Nonetheless, the specific Colletotrichum spp. that infect rubber trees in Yunnan Province, an important natural rubber base in China, have not been extensively investigated. Here, we isolated 118 Colletotrichum strains from rubber tree leaves exhibiting anthracnose symptoms in multiple plantations in Yunnan. Based on comparisons of their phenotypic characteristics and internal transcribed spacer ribosomal DNA sequences, 80 representative strains were chosen for additional phylogenetic analysis based on eight loci (act, ApMat, cal, CHS-1, GAPDH, GS, his3, and tub2), and nine species were identified. Colletotrichum fructicola, C. siamense, and C. wanningense were found to be the dominant pathogens causing rubber tree anthracnose in Yunnan. C. karstii was common, whereas C. bannaense, C. brevisporum, C. jinpingense, C. mengdingense, and C. plurivorum were rare. Among these nine species, C. brevisporum and C. plurivorum are reported for the first time in China, and two species are new to the world: C. mengdingense sp. nov. in the C. acutatum species complex and C. jinpingense sp. nov. in the C. gloeosporioides species complex. Their pathogenicity was confirmed with Koch's postulates by inoculating each species in vivo on rubber tree leaves. This study clarifies the geographic distribution of Colletotrichum spp. associated with anthracnose on rubber trees in representative locations of Yunnan, which is crucial for the implementation of quarantine measures.


Assuntos
Colletotrichum , Hevea , Hevea/genética , China , Filogenia , Doenças das Plantas , DNA Fúngico/genética , DNA Intergênico
7.
BMC Med Educ ; 21(1): 512, 2021 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-34583700

RESUMO

BACKGROUND: The global reputation of coronavirus disease (COVID-19) has led universities in China to conduct online teaching. However, the actual feedback from medical teachers and students regarding online education remains unclear. METHODS: A prospective questionnaire survey examined the current opinions of online education from teachers and students at the Medical School of Tongji University. RESULTS: A total of 488 valid questionnaires were collected (223 males, 45.7%; 265 females, 54.3%), including 394 students (80.7%) and 94 teachers (19.3%). Most teachers and students were "in favor of online teaching," had "positive views for online education," were "satisfied with online teaching," and "expected for regular online education," although students thought that "too much learning tasks had been assigned" (90.4% teachers vs. 43.1% students, P < 0.001) and "less teaching effect than in offline classes" (68.1% teachers vs. 43.4% students). Compared to female counterpart, male students had higher "learning interest" (27.6% vs. 14.9%), "learning attention" (29.2% vs. 14.4%), "learning efficiency" (30.2% vs. 16.7%), and "better learning effect" (27.6% vs. 15.3%). Furthermore, male students had a significantly rise in attendance rate. Compared with male teachers, female teachers had less "experience in online educational course recording" (25.9% vs. 50%) and "past training for online teaching" (53.7% vs. 77.5%). Furthermore, they tended to be more "resistant to online teaching" (44.4% vs. 22.5%) and less "ready for online teaching" (70.4% vs. 87.5%). There was no significant difference in the acceptance of online teaching among teachers in different age groups. CONCLUSIONS: Most teachers and students supported and were satisfied with the implementation of online education during the pandemic. Although teachers were less adaptable to online education, they still had positive opinions. Sex influenced the acceptance of online teaching. Male teachers and students showed better adaptability than their female counterparts. Although online teaching has advantages, it still cannot completely replace traditional offline teaching. As online education is a trend for future learning, universities should make more efforts to improve it, especially to provide more attention to female teachers and students.


Assuntos
COVID-19 , Educação a Distância , Estudantes de Medicina , Estudos Transversais , Feminino , Humanos , Masculino , Pandemias , Estudos Prospectivos , SARS-CoV-2 , Faculdades de Medicina , Universidades
8.
J Neurosci ; 39(15): 2837-2846, 2019 04 10.
Artigo em Inglês | MEDLINE | ID: mdl-30626698

RESUMO

The nucleus tractus solitarii (NTS) is implicated in the control of breathing, but the neuronal phenotype and circuit mechanism involved in such a physiological function remain incompletely understood. This study focused on the respiratory role of paired-like homeobox 2b gene (Phox2b)-expressing NTS neurons and sought to determine whether selective stimulation of this set of neurons activates breathing in male mice. A Cre-dependent vector encoding a Gq-coupled human M3 muscarinic receptor (hM3Dq) was microinjected into the NTS of Phox2b-Cre transgenic mice. The hM3Dq-transduced neurons were pharmacologically activated in conscious mice while respiratory effects were measured by plethysmography. We demonstrate that chemogenetic stimulation of Phox2b-expressing NTS neurons significantly increased baseline minute volume via an increase in respiratory frequency rather than tidal volume. Chemogenetic stimulation also synergized with moderate CO2 stimulation to enhance pulmonary ventilatory response. Selective ablation of Phox2b-expressing NTS neurons notably attenuated a hypercapnic ventilatory response. Moreover, histological evidence revealed that stimulation of Phox2b-expressing NTS neurons increased neuronal activity of the preBötzinger complex. Finally, we presented the neuroanatomical evidence of direct projection of Phox2b-expressing NTS neurons to putative respiratory central pattern generator. Overall, these findings suggest that selective activation of Phox2b-expressing NTS neurons potentiates baseline pulmonary ventilation via an excitatory drive to respiratory central pattern generator and this group of neurons is also required for the hypercapnic ventilatory response.SIGNIFICANCE STATEMENT The nucleus tractus solitarii (NTS) has been implicated in the control of breathing. The paired-like homeobox 2b gene (Phox2b) is the disease-defining gene for congenital central hypoventilation syndrome and is restrictively present in brainstem nucleus, including the NTS. Using a chemogenetic approach, we demonstrate herein that selective stimulation of Phox2b-expressing NTS neurons vigorously potentiates baseline pulmonary ventilation via an excitatory drive to respiratory central pattern generator in rodents. Genetic ablation of these neurons attenuates the hypercapnic ventilatory response. We also suggest that a fraction of Phox2b-expressing neurons exhibit CO2 sensitivity and presumably function as central respiratory chemoreceptors. The methodology is expected to provide a future applicability to the patients with sleep-related hypoventilation or apnea.


Assuntos
Proteínas de Homeodomínio/fisiologia , Neurônios/metabolismo , Respiração , Núcleo Solitário/metabolismo , Fatores de Transcrição/fisiologia , Animais , Dióxido de Carbono/farmacologia , Geradores de Padrão Central , Fenômenos Eletrofisiológicos/genética , Fenômenos Eletrofisiológicos/fisiologia , Proteínas de Homeodomínio/genética , Hipercapnia/fisiopatologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Microinjeções , Testes de Função Respiratória , Mecânica Respiratória , Núcleo Solitário/citologia , Fatores de Transcrição/genética
9.
Neurochem Res ; 43(9): 1779-1790, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29995175

RESUMO

Previous studies have shown that intermittent hypobaric hypoxia (IH) preconditioning protected neurons survival from brain ischemia. However, the mechanism remains to be elucidated. The present study explored the role of nitric oxide (NO) in the process by measuring the expression of NO synthase (NOS) and NO levels. Male Wistar rats (100) were randomly assigned into four groups: sham group, IH + sham group, ischemia group and IH + ischemia group. Rats for IH preconditioning were exposed to hypobaric hypoxia mimicking 5000 m high-altitude (PB = 404 mmHg, PO2 = 84 mmHg) 6 h/day, once daily for 28 days. Global brain ischemia was established by four-vessel occlusion that has been created by Pulsinelli. Rats were sacrificed at 7th day after the ischemia for neuropathological evaluation by thionin stain. In addition, the expression of neuronal NOS (nNOS), inducible NOS (iNOS), and NO content in the hippocampal CA1 subfield were measured at 2nd day and 7th day after the ischemia. Results revealed that global brain ischemia engendered delayed neuronal death (DND), both nNOS and iNOS expression up-regulated, and NO content increased in the hippocampal CA1 subfield. IH preconditioning reduced neuronal injury induced by the ischemia, and prevented the up-regulation of NOS expression and NO production. In addition, L-NAME + ischemia group was designed to detect whether depressing NO production could alleviate the DND. Pre-administration of L-NAME alleviated DND induced by the ischemia. These results suggest that IH preconditioning plays a protective role by inhibiting the over expression of NOS and NO content after brain ischemia.


Assuntos
Isquemia Encefálica/metabolismo , Região CA1 Hipocampal/metabolismo , Hipóxia/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Óxido Nítrico Sintase Tipo I/metabolismo , Óxido Nítrico/metabolismo , Animais , Isquemia Encefálica/patologia , Região CA1 Hipocampal/patologia , Hipóxia/patologia , Masculino , Distribuição Aleatória , Ratos , Ratos Wistar
10.
Neurochem Res ; 43(10): 2016, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30171421

RESUMO

The order of corresponding author was inadvertently published. Hence, the first and the second corresponding authors should be Min Zhang (hebmuzhangmin@163.com) and Jing-Ge Zhang (zhangjg001@163.com).

11.
Can J Physiol Pharmacol ; 96(8): 807-814, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29400080

RESUMO

Many studies have demonstrated that chronic intermittent hypobaric hypoxia (CIHH) can reduce blood pressure in spontaneously hypertensive rats and renovascular hypertensive (RVH) rats in which endothelial dysfunction is determined as a critical factor. However, whether CIHH can regulate vasodilation of the aorta in RVH rats remains unknown. The purpose of this study was to investigate the effect of CIHH on impaired relaxation of the aorta in the 2-kidney, 1-clip (2K1C) RVH rat model. The results showed CIHH improved the impaired endothelium-dependent relaxation in the 2K1C rat aorta. The endothelial dysfunction was prevented by the p38 antagonist SB203580, but not by the ERK1/2 antagonist PD98059 or JNK antagonist SP600125. Furthermore, the expression of p-eNOS, HIF-1α, and HIF-2α increased while that of p-p38 and BMP-4 decreased in CIHH-treated aortas from 2K1C rats. Finally, the p-eNOS expression was upregulated and the p-p38 expression was downregulated by pre-incubation of SB203580 or the BMP-4 antagonist Noggin with the aorta. CIHH ameliorated the impairment of endothelium-dependent relaxation through upregulating the expression of p-eNOS, which may be mediated by the inhibition of BMP-4/p-p38 MAPK, and upregulating the expression of HIFs in the 2K1C rat aorta.


Assuntos
Aorta/patologia , Hipertensão/patologia , Hipóxia/patologia , Rim/patologia , Instrumentos Cirúrgicos , Acetilcolina/farmacologia , Animais , Antracenos/farmacologia , Antracenos/uso terapêutico , Aorta/efeitos dos fármacos , Aorta/fisiopatologia , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Pressão Sanguínea/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Proteína Morfogenética Óssea 4/metabolismo , Proteínas de Transporte/farmacologia , Doença Crônica , Modelos Animais de Doenças , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/patologia , Endotélio Vascular/fisiopatologia , Flavonoides/farmacologia , Flavonoides/uso terapêutico , Hipertensão/tratamento farmacológico , Hipertensão/fisiopatologia , Hipóxia/fisiopatologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Imidazóis/farmacologia , Imidazóis/uso terapêutico , Técnicas In Vitro , Masculino , Óxido Nítrico Sintase Tipo III/metabolismo , Nitroprussiato/farmacologia , Fosforilação/efeitos dos fármacos , Piridinas/farmacologia , Piridinas/uso terapêutico , Ratos Sprague-Dawley , Sístole , Vasodilatação/efeitos dos fármacos , Proteínas Quinases p38 Ativadas por Mitógeno/antagonistas & inibidores , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
12.
Pharmazie ; 73(9): 503-507, 2018 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-30223932

RESUMO

The purpose of the present study was to dig into recent studies designed to characterize the impacts of 2'-deoxy-2'-ß-fluoro-4'-azidocytidine (FNC) on P-glycoprotein (P-gp), multidrug resistance-associated protein 2 (MRP2) and breast cancer resistance protein (BCRP). Specifically, the modulation effects of FNC on P-gp, MRP2 and BCRP protein expressions were assessed by western blot methods. 5 (and 6)-Carboxy-2',7'-dichloroflourescein (CDF) and BODIPY-prazosin were used to provide indications of alterations of MRP2 and BCRP activities. The effects of P-gp, MRP2 and BCRP on FNC were evaluated in the in situ single-pass intestinal perfusion model. The results showed that FNC at higher concentrations and with longer incubation times can upregulate the protein expression of P-gp, MRP2 and BCRP in Caco-2 cells. The upregulated proteins were also functionally active, as revealed by a lower degree of CDF and BODIPY-prazosin uptake by the cell monolayers. The intestinal absorptive coefficient (Peff) was observed to significantly increase with the inhibitors of P-gp, MRP2 and BCRP. These results suggested that FNC could modulate the expressions and functions of P-gp, MRP2 and BCRP, while P-gp, MRP2 and BCRP were involved in the efflux transport of FNC. The inductive effects of FNC on P-gp, MRP2 and BCRP suggested the possibility of FNC to contribute to the inter- and intra-individual variability of itself, as well as to alter the absorption of other drugs that may be administered concomitantly.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/genética , Azidas/farmacologia , Desoxicitidina/análogos & derivados , Proteínas Associadas à Resistência a Múltiplos Medicamentos/genética , Proteínas de Neoplasias/genética , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/metabolismo , Animais , Fármacos Anti-HIV/farmacologia , Transporte Biológico , Células CACO-2 , Desoxicitidina/farmacologia , Interações Medicamentosas , Humanos , Absorção Intestinal , Masculino , Proteína 2 Associada à Farmacorresistência Múltipla , Proteínas Associadas à Resistência a Múltiplos Medicamentos/metabolismo , Proteínas de Neoplasias/metabolismo , Ratos , Ratos Sprague-Dawley , Regulação para Cima/efeitos dos fármacos
13.
J Physiol ; 595(14): 4973-4989, 2017 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-28488367

RESUMO

KEY POINTS: Central hypercapnic hypoventilation is highly prevalent in children suffering from congenital central hypoventilation syndrome (CCHS). Mutations of the gene for paired-like homeobox 2b (Phox2b) are aetiologically associated with CCHS and Phox2b is present in central components of respiratory chemoreflex, such as the nucleus tractus solitarius (NTS). Injection of the neurotoxin substance P-saporin into NTS destroys Phox2b-expressing neurons. Impaired hypercapnic ventilatory response caused by this neurotoxin is attributable to a loss of CO2 -sensitive Phox2b-expressing NTS neurons. A subgroup of Phox2b-expressing neurons exhibits intrinsic chemosensitivity. A background K+ channel-like current is partially responsible for such chemosensitivity in Phox2b-expressing neurons. The present study helps us better understand the mechanism of respiratory deficits in CCHS and potentially locates a brainstem site for development of precise clinical intervention. ABSTRACT: The nucleus tractus solitarius (NTS) neurons have been considered to function as central respiratory chemoreceptors. However, the common molecular marker defined for these neurons remains unknown. The present study investigated whether paired-like homeobox 2b (Phox2b)-expressing NTS neurons are recruited in hypercapnic ventilatory response (HCVR) and whether these neurons exhibit intrinsic chemosensitivity. HCVR was assessed using whole body plethysmography and neuronal chemosensitivity was examined by patch clamp recordings in brainstem slices or dissociated neurons from Phox2b-EGFP transgenic mice. Injection of the neurotoxin substance P-saporin (SSP-SAP) into NTS destroyed Phox2b-expressing neurons. Minute ventilation and tidal volume were both reduced by 13% during exposure to 8% CO2 in inspired air when ∼13% of the Phox2b-expressing neurons were eliminated. However, a loss of ∼18% of these neurons was associated with considerable decreases in minute ventilation by ≥18% and in tidal volume by≥22% when challenged by ≥4% CO2 . In both cases, breathing frequency was unaffected. Most CO2 -activated neurons were immunoreactive to Phox2b. In brainstem slices, ∼43% of Phox2b-expressing neurons from Phox2b-EGFP mice displayed a sustained or transient increase in firing rate during physiological acidification (pH 7.0 or 8% CO2 ). Such a response was also present in dissociated neurons in favour of an intrinsic property. In voltage clamp recordings, a background K+ channel-like current was found in a subgroup of Phox2b-expressing neurons. Thus, the respiratory deficits caused by injection of SSP-SAP into the NTS are attributable to proportional lesions of CO2 /H+ -sensitive Phox2b-expressing neurons.


Assuntos
Proteínas de Homeodomínio/fisiologia , Hipercapnia/fisiopatologia , Neurônios/fisiologia , Núcleo Solitário/fisiologia , Fatores de Transcrição/fisiologia , Animais , Proteínas de Homeodomínio/genética , Masculino , Potenciais da Membrana , Camundongos Transgênicos , Neurônios/efeitos dos fármacos , Neurotoxinas/toxicidade , Respiração , Proteínas Inativadoras de Ribossomos Tipo 1/toxicidade , Saporinas , Núcleo Solitário/efeitos dos fármacos , Fatores de Transcrição/genética
14.
Neurochem Res ; 42(2): 501-512, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27822668

RESUMO

Chronic intermittent hypobaric hypoxia (CIHH) has protective effects on heart and brain against ischemia injury through mobilizing endogenous adaptive mechanisms. However, whether CIHH prevents against cognitive impairment was not elucidated. The present study aimed to investigate the effect and mechanism of CIHH treatment on ischemia/reperfusion (IR)-induced cognitive dysfunction. Mice were randomly divided into 8 groups: Control, Sham, CIHH (simulating 5000 m high-altitude for 28 days, 6 h per day), IR (three 16-min occlusions of bilateral common carotid arteries interrupted by two 10-min intervals), CIHH + IR, PD98059 (inhibitor of MEK1/2) + CIHH + IR, PD98059 + Sham and PD98059 + IR group. Morris water maze and step-down passive avoidance tests were performed to evaluate the capability of learning and memory 1 month after ischemia. Thionine dyeing was to examine histological manifestations of pyramidal neurons in hippocampus CA1 region. Western blotting assay was for measurement of the protein expressions in ERK1/2-CREB-BDNF signaling pathway. There were a shorter escape latency and a longer percentage of time retaining in the target quadrant in Morris water maze test, fewer times of errors in the step-down avoidance test and a higher neuronal density of the hippocampal CA1 subfield in CIHH + IR group than in IR group. CIHH upregulated the expressions of BDNF, phosphorylated CREB, ERK1/2 and TrkB with or without ischemia. The protective effects of CIHH were abolished by PD98059 administration 15 min before ischemia. CIHH ameliorated ischemia-induced cognitive dysfunction through activation of ERK1/2-CREB-BDNF signaling pathway.


Assuntos
Isquemia Encefálica/metabolismo , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Disfunção Cognitiva/metabolismo , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Hipóxia/metabolismo , Sistema de Sinalização das MAP Quinases/fisiologia , Animais , Isquemia Encefálica/prevenção & controle , Disfunção Cognitiva/prevenção & controle , Masculino , Aprendizagem em Labirinto/fisiologia , Camundongos , Camundongos Endogâmicos ICR , Distribuição Aleatória , Resultado do Tratamento
15.
Clin Exp Pharmacol Physiol ; 42(9): 950-955, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26173564

RESUMO

Emerging evidence has indicated that anandamide (AEA) is able to stimulate vasorelaxation in both spontaneously hypertensive rats (SHRs) and L-NAME-induced hypertensive rats. Yet it remains unknown whether AEA modulates vasomotion of the aorta in renovascular hypertensive (RVH) rats. The aim of present study is to explore the effect of AEA on the relaxation of thoracic aortas in two-kidney one-clip (2K1C)-induced RVH rats. It is demonstrated that AEA stimulates a pronounced relaxation in the aortas of 2K1C rats compared with sham rats. The enhanced relaxation caused by AEA in aortas from 2K1C rats was diminished in the presence of the cannabinoid receptor-1 (CB1 ) antagonist AM251 and the CB2 receptor antagonist AM630. Likewise, the vasodilation action of AEA was blocked in L-NAME-treated or endothelium-denuded aortas. The Western blot results revealed that the expression of CB1 and CB2 receptors was increased in the 2K1C rat aortas compared with sham rats. The phosphorylation of endothelial nitric oxide synthase (p-eNOS) at the activation site Ser1177 was enhanced in AEA-treated rings from 2K1C rats in both time-dependent and dose-dependent manners. The augmented p-eNOS expression was inhibited by the co-treatment with AM251 or AM630. Taken together, the present study demonstrated that AEA enhanced endothelium-dependent aortic relaxation through activation of both CB1 and CB2 receptors and P-eNOS/NO pathway in 2K1C rats.

16.
Amino Acids ; 46(6): 1537-45, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24643365

RESUMO

Our previous study has shown that cerebral ischemic preconditioning (CIP) can up-regulate the expression of glial glutamate transporter-1 (GLT-1) during the induction of brain ischemic tolerance in rats. The present study was undertaken to further explore the uptake activity of GLT-1 in the process by observing the changes in the concentration of extracellular glutamate with cerebral microdialysis and high-performance liquid chromatography. The results showed that a significant pulse of glutamate concentration reached the peak value of sevenfold of the basal level after lethal ischemic insult, which was associated with delayed neuronal death in the CA1 hippocampus. When the rats were pretreated 2 days before the lethal ischemic insult with CIP which protected the pyramidal neurons against delayed neuronal death, the peak value of glutamate concentration decreased to 3.9 fold of the basal level. Furthermore, pre-administration of dihydrokainate, an inhibitor of GLT-1, prevented the protective effect of CIP on ischemia-induced CA1 cell death. At the same time, compared with the CIP + Ischemia group, the peak value of glutamate concentration significantly increased and reached sixfold of the basal level. These results indicate that CIP induced brain ischemic tolerance via up-regulating GLT-1 uptake activity for glutamate and then decreasing the excitotoxicity of glutamate.


Assuntos
Transportador 2 de Aminoácido Excitatório/biossíntese , Ácido Glutâmico/metabolismo , Precondicionamento Isquêmico , Animais , Transportador 2 de Aminoácido Excitatório/metabolismo , Hipocampo/metabolismo , Ácido Caínico/análogos & derivados , Ácido Caínico/farmacologia , Masculino , Microdiálise , Ratos Wistar , Regulação para Cima
17.
Artigo em Inglês | MEDLINE | ID: mdl-38798210

RESUMO

BACKGROUND: Calcitonin (CT) is a sensitive serum marker of medullary thyroid carcinoma usually detected via immunoassays; however, its levels are easily disturbed by several endogenous factors. OBJECTIVE: The study aimed to discuss a case of suspected interference resulting in aberrant CT values and review previous reports of CT interference. METHODS: A female patient visited our clinic with a physical ultrasound examination showing a slightly enlarged thyroid gland with small nodules. She had elevated CT levels, inconsistent with the clinical presentation and other findings. We evaluated the results by retesting using the same platform, platform validation, multiplex dilution, Polyethylene Glycol (PEG) precipitation, heterophilic blocking tubes, and RET gene analysis. RESULTS: Retesting CT using the same platform confirmed the high value obtained. However, serial dilution of the sample produced nonlinear results, suggesting some interference. While PEG precipitation did not significantly reduce the CT level, incubating the sample in HBTs normalized the CT value, indicating interference from heterophilic antibodies. Gene sequencing revealed no RET mutations. CONCLUSION: In cases where elevated CT levels are inconsistent with clinical presentations and other findings, the laboratory technicians should communicate with clinicians, analyze the reasons for the inconsistent results, and use different methods to verify the results. Accurate testing provides realistic and reliable data for doctors and patients and helps to avoid unnecessary procedures.

18.
J Clin Endocrinol Metab ; 109(7): 1793-1802, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38214112

RESUMO

CONTEXT: Current metabolomics studies in diabetes have focused on the fasting state, while only a few have addressed the satiated state. OBJECTIVE: We combined the oral glucose tolerance test (OGTT) and metabolomics to examine metabolite-level changes in populations with different glucose tolerance statuses and to evaluate the potential risk of these changes for diabetes. METHODS: We grouped participants into those with normal glucose tolerance (NGT), impaired glucose regulation (IGR), and newly diagnosed type 2 diabetes (NDM). During the OGTT, serum was collected at 0, 30, 60, 120, and 180 minutes. We evaluated the changes in metabolite levels during the OGTT and compared metabolic profiles among the 3 groups. The relationship between metabolite levels during the OGTT and risk of diabetes and prediabetes was analyzed using a generalized estimating equation (GEE). The regression results were adjusted for sex, body mass index, fasting insulin levels, heart rate, smoking status, and blood pressure. RESULTS: Glucose intake altered metabolic profile and induced an increase in glycolytic intermediates and a decrease in amino acids, glycerol, ketone bodies, and triglycerides. Isoleucine levels differed between the NGT and NDM groups and between the NGT and IGR groups. Changes in sarcosine levels during the OGTT in the diabetes groups were opposite to those in glycine levels. GEE analysis revealed that during OGTT, isoleucine, sarcosine, and acetic acid levels were associated with NDM risks, and isoleucine and acetate levels with IGR risks. CONCLUSION: Metabolic profiles differ after glucose induction in individuals with different glucose tolerance statuses. Changes in metabolite levels during OGTT are potential risk factors for diabetes development.


Assuntos
Glicemia , Diabetes Mellitus Tipo 2 , Intolerância à Glucose , Teste de Tolerância a Glucose , Isoleucina , Sarcosina , Humanos , Masculino , Feminino , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Mellitus Tipo 2/metabolismo , Pessoa de Meia-Idade , Isoleucina/sangue , Fatores de Risco , Sarcosina/análogos & derivados , Sarcosina/sangue , Glicemia/análise , Glicemia/metabolismo , Adulto , Intolerância à Glucose/sangue , Intolerância à Glucose/epidemiologia , Intolerância à Glucose/metabolismo , Estado Pré-Diabético/sangue , Estado Pré-Diabético/epidemiologia , Estado Pré-Diabético/metabolismo , Metabolômica , Idoso , Biomarcadores/sangue
19.
Nat Prod Res ; : 1-8, 2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38684011

RESUMO

The extraction, isolation, structural characterisation and biological activities of polysaccharides from Amorpha fruticosa flowers were investigated. First, the crude polysaccharide AFP was extracted, and two major purified polysaccharide fractions AFP-2 and AFP-3 were isolated. The molecular weight and monosaccharide compositions of AFP-2 and AFP-3 were determined. Then the antioxidant activities of AFP, AFP-2 and AFP-3 were assessed by DPPH radical, ß-Carotene bleaching and hydroxyl radical assays. All three tested polysaccharides showed good antioxidant activity while AFP was the strongest one. The study also showed that AFP, AFP-2 and AFP-3 have good tyrosinase inhibition, moisture absorption and retention activities. The results will provide a helpful reference for the application of polysaccharide from Amorpha fruticosa flowers as a natural cosmetic ingredient.

20.
Artigo em Inglês | MEDLINE | ID: mdl-38934120

RESUMO

Background: Hepatocellular carcinoma (HCC) is a highly aggressive cancer. This study aims to elucidate the role of Glyoxylate reductase/hydroxypyruvate reductase (GRHPR) in HCC proliferation and metastasis, along with its molecular mechanism, and to identify miRNAs targeting GRHPR. Materials and Methods: Expression levels of GRHPR and miR-138-5p were assessed using real-time fluorescent quantitative polymerase chain reaction and Western blot techniques. Bioinformatic analysis was employed to identify miRNAs targeting GRHPR, and the results were confirmed via dual-luciferase reporter assays. HCC cell lines overexpressing GRHPR were established to investigate its roles in cell proliferation, migration, and invasion. The biological function of miR-138-5p targeting GRHPR in HCC cells was also evaluated. Furthermore, a xenograft mouse model was utilized to examine the in vivo functions of GRHPR. Results: GRHPR expression was downregulated in HCC, whereas miR-138-5p was upregulated. Overexpression of GRHPR suppressed HCC cell proliferation, migration, and invasion. Conversely, inhibition of GRHPR by miR-138-5p promoted HCC cell proliferation and invasive properties. MiR-138-5p was found to regulate Phosphoinositide 3-kinase (PI3K) and protein kinase B (AKT) phosphorylation levels by inhibiting GRHPR expression. Conclusion: This study highlights GRHPR's role as a tumor suppressor in HCC, with its function being regulated by miR-138-5p.

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