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1.
ACS Omega ; 4(15): 16543-16550, 2019 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-31616834

RESUMO

The incorporation of phosphonate ligands into the cyclometalated iridium(III) complexes can not only tune their electronic and optical properties but also provide the possibility of anchoring these molecules on the semiconductor surfaces for further applications. Herein, we report the first examples of mononuclear cyclometallated iridium(III) complexes incorporating phosphonate ligands, namely, [Ir(ppy)2(HL1)]·0.5H2O (1), [Ir(ppy)2(HL2)]·0.5H2O (2), [Ir(dfppy)2(HL1)] (3), and [Ir(dfppy)2(HL2)]·3.5H2O (4) (ppy = 2-phenylpyridine, dfppy = 2-(2,4-difluorophenyl)pyridine, H2L1 = 2-pyridylphosphonic acid, H2L2 = 2-quinolinephosphonic acid). Luminescent spectra are studied both in solution and in the solid state, and significantly red-shifted broad emission bands are observed in complexes 2 and 4. The experimental and density functional theory (DFT) time-dependent-DFT calculation results indicate that the expansion of the aromatic conjugation length in the ancillary phosphonate ligands decreases the lowest unoccupied molecular orbital energy levels of the systems, originating from the triplet state associated with the ancillary ligand such as 3MLCT, 3LC, and 3LLCT charge-transfer transitions.

2.
Sci Rep ; 9(1): 2423, 2019 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-30787467

RESUMO

Dehydrogenase pathway, one of diaminopimelate pathway, is important to the biosynthesis of L-lysine and peptidoglycan via one single reaction catalyzed by meso-diaminopimelate dehydrogenase (DapDH). In this study, the thermostable DapDH was introduced into diaminopimelate pathway that increased the final titer (from 71.8 to 119.5 g/L), carbon yield (from 35.3% to 49.1%) and productivity (from 1.80 to 2.99 g/(L∙h)) of L-lysine by LATR12-2∆rpiB::ddhSt in fed-batch fermentation. To do this, the kinetic properties and the effects of different DapDHs on L-lysine production were investigated, and the results indicated that overexpression of StDapDH in LATR12-2 was beneficial to construct an L-lysine producer with good productive performance because it exhibited the best of kinetic characteristics and optimal temperature as well as thermostability in reductive amination. Furthermore, ammonium availability was optimized, and found that 20 g/L of (NH4)2SO4 was the optimal ammonium concentration for improving the efficiency of L-lysine production by LATR12-2∆rpiB::ddhSt. Metabolomics analysis showed that introducing the StDapDH significantly enhanced carbon flux into pentose phosphate pathway and L-lysine biosynthetic pathway, thus increasing the levels of NADPH and precursors for L-lysine biosynthesis. This is the first report of a rational modification of diaminopimelate pathway that improves the efficiency of L-lysine production through overexpression of thermostable DapDH in E. coli.

3.
Acta Pharmacol Sin ; 40(5): 589-598, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30030529

RESUMO

High-mobility group box 1 (HMGB1) exhibits various functions according to its subcellular location, which is finely conditioned by diverse post-translational modifications, such as acetylation. The nuclear HMGB1 may prevent from cardiac hypertrophy, whereas its exogenous protein is proven to induce hypertrophic response. This present study sought to investigate the regulatory relationships between poly(ADP-ribose) polymerase 1 (PARP1) and HMGB1 in the process of pathological myocardial hypertrophy. Primary-cultured neonatal rat cardiomyocytes (NRCMs) were respectively incubated with three cardiac hypertrophic stimulants, including angiotensin II (Ang II), phenylephrine (PE), and isoproterenol (ISO), and cell surface area and the mRNA expression of hypertrophic biomarkers were measured. the catalytic activity of PARP1 was remarkably enhanced, meanwhile HMGB1 excluded from the nucleus. PARP1 overexpression by infecting with adenovirus PARP1 (Ad-PARP1) promoted the nuclear export of HMGB1, facilitated its secretion outside the cell, aggravated cardiomyocyte hypertrophy, which could be alleviated by HMGB1 overexpression. PE treatment led to the similar results, while that effect was widely depressed by PARP1 silencing or its specific inhibitor AG14361. Moreover, SD rats were intraperitoneally injected with 3-aminobenzamide (3AB, 20 mg/kg every day, a well-established PARP1 inhibitor) 7 days after abdominal aortic constriction (AAC) surgery for 6 weeks, echocardiography and morphometry of the hearts were measured. Pre-treatment of 3AB relieved AAC-caused the translocation of nuclear HMGB1 protein, cardiac hypertrophy, and heart dysfunction. Our research offers a novel evidence that PARP1 combines with HMGB1 and accelerates its translocation from nucleus to cytoplasm, and the course finally causes cardiac hypertrophy.


Assuntos
Cardiomegalia/etiologia , Núcleo Celular/metabolismo , Proteína HMGB1/metabolismo , Poli(ADP-Ribose) Polimerase-1/metabolismo , Transporte Ativo do Núcleo Celular/efeitos dos fármacos , Angiotensina II/farmacologia , Animais , Isoproterenol/farmacologia , Masculino , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Fenilefrina/farmacologia , Ratos Sprague-Dawley
4.
Acta Pharmacol Sin ; 39(12): 1837-1846, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29991711

RESUMO

Vascular endothelial cell senescence is a leading cause of age-associated and vascular diseases. Mammalian target of rapamycin complex 2 (mTORC2) is a conserved serine/threonine (Ser/Thr) protein kinase that plays an important regulatory role in various cellular processes. However, its impact on endothelial senescence remains controversial. In this study we investigated the role and molecular mechanisms of mTORC2 in endothelial senescence. A replicative senescence model and H2O2-induced premature senescence model were established in primary cultured human umbilical vein endothelial cells (HUVECs). In these senescence models, the formation and activation of mTORC2 were significantly increased, evidenced by the increases in binding of Rictor (the essential component of mTORC2) to mTOR, phosphorylation of mTOR at Ser2481 and phosphorylation of Akt (the effector of mTORC2) at Ser473. Knockdown of Rictor or treatment with the Akt inhibitor MK-2206 attenuated senescence-associated ß-galactosidase (ß-gal) staining and expression of p53 and p21 proteins in the senescent endothelial cells, suggesting that mTORC2/Akt facilitates endothelial senescence. The effect of mTORC2/Akt on endothelial senescence was due to suppression of nuclear factor erythroid 2-related factor 2 (Nrf2) at the transcriptional level, since knockdown of Rictor reversed the reduction of Nrf2 mRNA expression in endothelial senescence. Furthermore, mTORC2 suppressed the expression of Nrf2 via the Akt/GSK-3ß/C/EBPα signaling pathway. These results suggest that the mTORC2/Akt/GSK-3ß/C/EBPα/Nrf2 signaling pathway is involved in both replicative and inducible endothelial senescence. The deleterious role of mTORC2 in endothelial cell senescence suggests therapeutic strategies (targeting mTORC2) for aging-associated diseases and vascular diseases.


Assuntos
Senescência Celular/fisiologia , Células Endoteliais/fisiologia , Alvo Mecanístico do Complexo 2 de Rapamicina/fisiologia , Proteína alfa Estimuladora de Ligação a CCAAT/metabolismo , Glicogênio Sintase Quinase 3 beta/metabolismo , Células Endoteliais da Veia Umbilical Humana , Humanos , Fator 2 Relacionado a NF-E2/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/fisiologia
5.
BMC Cardiovasc Disord ; 17(1): 144, 2017 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-28578664

RESUMO

BACKGROUND: We analyzed the relationship of -794 CATT5-8 MIF polymorphisms with soluble MIF in Coronary Atherosclerotic Disease (CAD) patients. METHODS: A total of 256 patients selected, on which 186 normal-coronary and 70 Coronary artery disease subjects, were recruited in the study (Retrospectively registered). Genotyping of -794 CATT5-8 polymorphisms were performed by PCR and DNA sequencing. Serum MIF levels were measured using an ELISA kit. Patients were classified by coronary angiogram, and CAD based on Gensini's integral degree (angiographic scoring system). RESULTS: The allele frequency and genotype frequency of -794 CATT5-8 did not show any differences in normal-coronary subjects and CAD subjects. In CAD patients, serum MIF levels was lower in CATT (5) subjects than in CATT (7) subjects, while the genotype of -794 CATT5-8 did not show differences in serum MIF levels. In addition, we found a decrease in serum MIF levels in carriers of the (5/5) genotypes the -794 CATT5-8 MIF polymorphisms, although it was not significant. There was no relationship of CAD class and the allele frequency of -794 CATT5-8. CONCLUSIONS: This study found no association between CAD class and -794 CATT5-8 MIF polymorphisms with soluble MIF levels in CAD Subjects. TRIAL REGISTRATION: NCT01750502 (November 2012, Retrospectively registered).


Assuntos
Doença da Artéria Coronariana/genética , Estenose Coronária/genética , Oxirredutases Intramoleculares/genética , Fatores Inibidores da Migração de Macrófagos/genética , Polimorfismo Genético , Regiões Promotoras Genéticas , Angiografia Coronária , Doença da Artéria Coronariana/sangue , Doença da Artéria Coronariana/diagnóstico por imagem , Estenose Coronária/sangue , Estenose Coronária/diagnóstico por imagem , Ensaio de Imunoadsorção Enzimática , Frequência do Gene , Estudos de Associação Genética , Predisposição Genética para Doença , Humanos , Oxirredutases Intramoleculares/sangue , Fatores Inibidores da Migração de Macrófagos/sangue , Fenótipo , Reação em Cadeia da Polimerase , Valor Preditivo dos Testes , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Índice de Gravidade de Doença
6.
Chemistry ; 23(27): 6615-6624, 2017 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-28317183

RESUMO

Artificial control and engineering of metal-organic framework (MOF) crystals with defects can endow them with suitable properties for applications in gas storage, separation, and catalysis. A series of defective iridium-containing MOFs, [Zn4 (µ4 -O)(Ir-A)2(1-x) (Ir-B)2x ] (ZnIr-MOF-dx ), were synthesized by doping heterostructured linker Ir-BH3 into the parent [Zn4 (µ4 -O)(Ir-A)2 ] (ZnIr-MOF), in which Ir-AH3 represents [Ir(ppy-COOH)3 ] (ppyCOOH=3-(pyridin-2-yl)benzoic acid) and Ir-BH3 is [Ir(ppy-COOH)2 (2-pyPO3 H)] (2-pyPO3 H2 =2-pyridylphosphonic acid). Samples with different degrees of defects were characterized by SEM, IR and NMR spectroscopy, powder XRD measurements, and thermal and elemental analyses. ZnIr-MOF-d0.3 was selected as a representative for gas (N2 , CO2 ) or vapor (H2 O, alcohol) sorption studies. The results demonstrate that defective ZnIr-MOF-d0.3 possesses multiple pore size distributions, ranging from micro- to mesopores, unlike the parent material, which shows a uniform micropore distribution. The hydrophilicity of the interior surface is also increased after defect engineering. As a result, ZnIr-MOF-d0.3 shows an enhanced adsorption capability toward n-butanol, relative to that of the parent compound. Optical studies reveal that both ZnIr-MOF and ZnIr-MOF-d0.3 have low band gaps (2.35 and 2.40 eV), corresponding to semiconductors. ZnIr-MOF-d0.3 exhibits dramatically increased photocatalytic efficiency for dye degradation.

7.
Diagn Pathol ; 11(1): 78, 2016 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-27535029

RESUMO

BACKGROUND: Xanthoma disseminatum (XD) is a rare benign histiocytic proliferating disease of non-Langerhans cell origin, which is clinically mainly characterized by cutaneous or mucous lesions. Although XD is acknowledged of one systematic disease, involvement of the central nervous system is quite rare. CASE PRESENTATION: We presented one 34-year-old Chinese female with disseminated intracranial XD without cutaneous or oral mucosal papules and masses of the other organs. MR imaging displayed multiple heterogeneous masses with intense enhancement in the right frontal lobe, temporal lobe, corpus callosum, left cuneus, suprasellar region, and right cerebellum. Pathological examination showed a neoplastic lesion composed of plentiful epitheloid or spindle cells. The cell had pink cytoplasm of vacuolation and foam with deviated nucleus absent of atypia and mitosis. The histiocytic markers including CD163, CD11c, Mac387 and CD68 were positive, whereas S-100, CD1a, GFAP, CD21, CD23 and so on were negative immunohistochemically. CONCLUSIONS: Intracranial XD without systemic involvement was extremely rare, which was supposed to be considered in differential diagnosis with other neoplasms of histiocytic origin or gliomas.


Assuntos
Encefalopatias/diagnóstico , Encéfalo , Histiocitose de Células não Langerhans/diagnóstico , Adulto , Biomarcadores/análise , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Encéfalo/patologia , Encefalopatias/diagnóstico por imagem , Encefalopatias/metabolismo , Encefalopatias/patologia , Diagnóstico Diferencial , Feminino , Histiocitose de Células não Langerhans/diagnóstico por imagem , Histiocitose de Células não Langerhans/metabolismo , Histiocitose de Células não Langerhans/patologia , Humanos , Imuno-Histoquímica , Imagem por Ressonância Magnética , Valor Preditivo dos Testes
8.
BMC Cardiovasc Disord ; 16: 64, 2016 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-27044385

RESUMO

BACKGROUND: In recent years, radiofrequency catheter ablation(RFCA) has been established as an effective therapy for idiopathic premature ventricular contractions (PVCs), however, its effect on the narrow PVCs (QRS duration < 130 msec) with qR pattern in inferior leads, may not been fully concluded. METHODS: Characteristics of 12-lead electrocardiogram (ECG) and electrophysiologic recordings were analyzed in 40 patients with symptomatic PVCs manifesting narrow QRS complex with qR pattern in inferior leads. The procedure of RFCA was performed based on pace mapping and activation mapping. RESULTS: Among the 40 patients with narrow PVCs, complete elimination of PVCs was achieved by RFCA in 35 patients during a median follow-up period of 23 months. Successful ablation was achieved on 19 patients at the sites where earliest Purkinje potentials were recorded in left ventricular anterosuperior septum, thus PVCs arising from left anterior fascicle (LAF) were confirmed, for these PVCs, the QRS morphology were right bundle branch and left posterior fascicle block (RBBB + LPFB) with rightward axis, the average QRS duration 116.07 ± 7.96 ms, R or rsR'in lead V1,with transition zone ahead of lead V1 in precordial leads. Another 16 successful RFCA were achieved by energy delivery at interleaflet triangle(ILT) between right coronary cusp(RCC) and left coronary cusp(LCC) where no Purkinje potentials were recorded, for narrow PVCs arising from the L-RCC ILT, the QRS morphology were similar to the PVCs arising from LAF but much narrower in QRS duration (100.44 ± 3.49 vs. 116.07 ± 7.96 ms, p < 0.05), they were also R or Rs in lead V1 with the transition zone ahead of lead V1. For 5 symptomatic narrow PVCs failed to the procedure of RFCA, their electrocardiographic characteristics showed that the narrowest QRS duration (91.80 ± 6.94 vs. 100.44 ± 3.49, 116.07 ± 7.96 ms, p < 0.05), rs or rS (r/s or r/S≦1) morphology in lead V1 with the precordial transition zone behind lead V3. CONCLUSIONS: Most of idiopathic PVCs of narrow QRS duration (<130 msec) with qR pattern in inferior leads can be cured by the procedure of RFCA. On the basis of our study, we proposed that for narrow PVCs presenting qR pattern in inferior leads, when the ablation procedure failed at proximity of LAF within left anterosuperior septum, mapping and ablation in L-RCC ILT can be tried. The present findings can be helpful for planning catheter ablation for narrow PVCs manifesting qR in inferior leads.


Assuntos
Eletrocardiografia , Técnicas Eletrofisiológicas Cardíacas , Sistema de Condução Cardíaco/fisiopatologia , Complexos Ventriculares Prematuros/diagnóstico , Potenciais de Ação , Adolescente , Adulto , Ablação por Cateter , Feminino , Sistema de Condução Cardíaco/cirurgia , Frequência Cardíaca , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Retrospectivos , Resultado do Tratamento , Complexos Ventriculares Prematuros/fisiopatologia , Complexos Ventriculares Prematuros/cirurgia , Adulto Jovem
9.
Mol Med Rep ; 12(3): 4370-4375, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26130140

RESUMO

The echinoderm microtubule associated protein like 4­anaplastic lymphoma kinase (EML4­ALK) fusion is almost mutually exclusive to epidermal growth factor receptor (EGFR) or K­RAS mutation in non­small cell lung cancer (NSCLC), and it is extremely rare for patients to exhibit both mutations. The present study reported the case of a 71-year­old female diagnosed with adenocarcinoma, exhibiting mutations in EGFR and EML4­ALK. The present study treated this patient with EGFR­TK inhibitors, as the first line therapy, and gefitinib therapy revealed a good response until now. In addition, previously reported cases and associated literature were reviewed. The present study provided a greater understanding of the molecular biology and optimal treatment for patients with NSCLC with >1 driver mutation.


Assuntos
Adenocarcinoma/diagnóstico por imagem , Neoplasias Ósseas/diagnóstico por imagem , Receptores ErbB/genética , Neoplasias Pulmonares/diagnóstico por imagem , Receptores Proteína Tirosina Quinases/genética , Adenocarcinoma/genética , Adenocarcinoma/secundário , Idoso , Quinase do Linfoma Anaplásico , Neoplasias Ósseas/genética , Neoplasias Ósseas/secundário , Análise Mutacional de DNA , Feminino , Estudos de Associação Genética , Predisposição Genética para Doença , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Proteínas de Fusão Oncogênica/genética , Radiografia , Translocação Genética
10.
Biomed Res Int ; 2015: 175291, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25821786

RESUMO

Dyslipidemia increases the risks for atherosclerosis in part by impairing endothelial integrity. Endothelial progenitor cells (EPCs) are thought to contribute to endothelial recovery after arterial injury. Oxidized low-density lipoprotein (ox-LDL) can induce EPC dysfunction, but the underlying mechanism is not well understood. Human EPCs were cultured in endothelial growth medium supplemented with VEGF (10 ng/mL) and bFGF (10 ng/mL). The cells were treated with ox-LDL (50 µg/mL). EPC proliferation was assayed by using CCK8 kits. Expression and translocation of nuclear factor-kabba B (NF-κB) were evaluated. The level of reactive oxygen species (ROS) in cells was measured using H2DCF-DA as a fluorescence probe. The activity of NADPH oxidase activity was determined by colorimetric assay. Ox-LDL significantly decreased the proliferation, migration, and adhesion capacity of EPCs, while significantly increased ROS production and NADPH oxidase expression. Ox-LDL induced NF-κB P65 mRNA expression and translocation in EPCs. Thus ox-LDL can induce EPC dysfunction at least by increasing expression and translocation of NF-κB P65 and NADPH oxidase activity, which represents a new mechanism of lipidemia-induced vascular injury.


Assuntos
Células Endoteliais/citologia , Células Endoteliais/metabolismo , Lipoproteínas LDL/farmacologia , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , NF-kappa B/metabolismo , Células Cultivadas , Células Endoteliais/efeitos dos fármacos , Feminino , Sangue Fetal/citologia , Humanos , Células-Tronco Mesenquimais/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/fisiologia
11.
Mol Cell Endocrinol ; 392(1-2): 14-22, 2014 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-24859603

RESUMO

Poly(ADP-ribose) polymerase-1 (PARP-1) enzyme, as a sensor of DNA damage, could convert nicotinamide adenine dinucleotide (NAD) into long poly(ADP-ribose) chains and regulate many cellular processes, including DNA repair, gene transcription, cell survival and chromatin remodeling. However, excessive activation of PARP-1 depletes its substrate NAD and leads to cell death. Mounting evidences have shown that PARP-1 overactivation plays a pivotal role in the pathogenesis of cardiac hypertrophy and heart failure. In present study, a novel PARP-1 inhibitor AG-690/11026014 (6014) was identified based on virtual screening and validated by bioassay. Our results further showed that 6014 prevented the cardiomyocytes from AngII-induced hypertrophy, accompanying attenuation of the mRNA and protein expressions of atrial natriuretic factor (ANF) and brain natriuretic peptide (BNP), and reduce in the cell surface area. Additionally, 6014 reversed the depletion ofcellular NAD and SIRT6 deacetylase activity induced by AngII in cardiomyocytes. These observations suggest that anti-hypertrophic effect of 6014 might be partially attributed to the rescue of NAD depletion and subsequent restoring of SIRT6 activity by inhibition of PARP-1. Moreover, 6014 attenuated the generation of oxidative stress via suppression of NADPH oxidase 2 and 4, which might probably contribute to the inhibition of PARP-1.


Assuntos
Cardiomegalia/enzimologia , Cardiomegalia/prevenção & controle , Cardiotônicos/uso terapêutico , Citoproteção/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Miócitos Cardíacos/patologia , Inibidores de Poli(ADP-Ribose) Polimerases , Tioglicolatos/farmacologia , Xantinas/farmacologia , Angiotensina II , Animais , Cardiotônicos/farmacologia , Avaliação Pré-Clínica de Medicamentos , Ativação Enzimática/efeitos dos fármacos , Inibidores Enzimáticos/análise , Inibidores Enzimáticos/química , Humanos , Concentração Inibidora 50 , Glicoproteínas de Membrana/metabolismo , Simulação de Acoplamento Molecular , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/enzimologia , NAD/metabolismo , NADPH Oxidase 2 , NADPH Oxidase 4 , NADPH Oxidases/metabolismo , Poli(ADP-Ribose) Polimerases/metabolismo , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo , Proteínas Recombinantes/metabolismo , Sirtuínas/metabolismo , Tioglicolatos/análise , Tioglicolatos/química , Regulação para Cima/efeitos dos fármacos , Xantinas/análise , Xantinas/química
12.
J Zhejiang Univ Sci B ; 14(8): 754-8, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23897796

RESUMO

Increased delay in visiting a hospital for patients with ST-segment elevation myocardial infarction (STEMI) is often associated with poor outcomes. The factors associated with the decision time were analyzed by comparing the characteristics of patients with delays longer or shorter than the median of 60 min. Pre-hospital delay tended to be longer for patients living in suburban areas compared to those in urban areas (P=0.015). Shorter decision time was more likely among older patients. Being married, medical insurance coverage, and the level of educational qualification did not affect decision time. More efforts should be paid to educate the patients with high risk in suburban areas in order to effectively reduce pre-hospital delays.


Assuntos
Infarto do Miocárdio/diagnóstico , Infarto do Miocárdio/psicologia , Aceitação pelo Paciente de Cuidados de Saúde , Idoso , China , Tomada de Decisões , Diagnóstico Tardio , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/terapia , Fatores Socioeconômicos , População Suburbana , Fatores de Tempo , População Urbana
13.
J Exp Biol ; 216(Pt 17): 3358-68, 2013 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-23737554

RESUMO

We evaluated factors limiting lactating Mongolian gerbils (Meriones unguiculatus) at three temperatures (10, 21 and 30°C). Energy intake and daily energy expenditure (DEE) increased with decreased ambient temperature. At peak lactation (day 14 of lactation), energy intake increased from 148.7±5.7 kJ day(-1) at 30°C to 213.1±8.2 kJ day(-1) at 21°C and 248.7±12.3 kJ day(-1) at 10°C. DEE increased from 105.1±4.0 kJ day(-1) at 30°C to 134.7±5.6 kJ day(-1) at 21°C and 179.5±8.4 kJ day(-1) at 10°C on days 14-16 of lactation. With nearly identical mean litter sizes, lactating gerbils at 30°C exported 32.0 kJ day(-1) less energy as milk at peak lactation than those allocated to 10 or 21°C, with no difference between the latter groups. On day 14 of lactation, the litter masses at 10 and 30°C were 12.2 and 9.3 g lower than those at 21°C, respectively. Lactating gerbils had higher thermal conductance of the fur and lower UCP-1 levels in brown adipose tissue than non-reproductive gerbils, independent of ambient temperature, suggesting that they were attempting to avoid heat stress. Thermal conductance of the fur was positively related to circulating prolactin levels. We implanted non-reproductive gerbils with mini-osmotic pumps that delivered either prolactin or saline. Prolactin did not influence thermal conductance of the fur, but did reduce physical activity and UCP-1 levels in brown adipose tissue. Transferring lactating gerbils from warm to hot conditions resulted in reduced milk production, consistent with the heat dissipation limit theory, but transferring them from warm to cold conditions did not elevate milk production, consistent with the peripheral limitation hypothesis, and placed constraints on pup growth.


Assuntos
Regulação da Temperatura Corporal , Ingestão de Alimentos , Ingestão de Energia , Gerbillinae/fisiologia , Lactação , Animais , Feminino , Temperatura Ambiente
14.
World J Surg Oncol ; 11: 147, 2013 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-23799942

RESUMO

BACKGROUND: To explore metal implants' thermal effect on radiofrequency ablation (RFA) and ascertain distance-thermal relationship between the metal implants and radiofrequency (RF) electrode. METHODS: Metal implants models were established in seven in-vitro porcine livers using silver clips or 125I seeds. RFA were conducted centering the RF electrode axis1 cm away from them, with one side containing a metal implants model the test group and the other side the control group. The thermometric needles were used to measure multi-point temperatures in order to compare the time-distance-temperature difference between the two groups. The gross scopes of the ablation of the two groups were measured and the tissues were analyzed for microscopic histology. RESULTS: At the ablation times of 8, 12, and 15 min, the average multi-point temperatures of the test group and the control group were 48.2±18.07°C, 51.5±19.57°C, 54.6±19.75°C, and 48.6±17.69°C, 52.2±19.73°C, 54.9±19.24°C, respectively, and the differences were not statistically significant (n=126, P>0.05). At the ablation times of 12 and 15 min, the ablation scopes of the test group and the control group were (horizontal/longitudinal diameter) 1.55/3.48 cm, 1.89/3.72 cm, and 1.56/3.48 cm, 1.89/3.72 cm, respectively, and the differences were not statistically significant (n=14, P>0.05). The two groups had the same manifestations in microscopy. CONCLUSIONS: Metal implants do not cause significant thermal effect on RFA.


Assuntos
Ablação por Cateter , Fígado/cirurgia , Metais , Modelos Animais , Próteses e Implantes , Animais , Temperatura Corporal , Eletrodos , Técnicas In Vitro , Fígado/patologia , Suínos
15.
Zhonghua Bing Li Xue Za Zhi ; 42(1): 4-9, 2013 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-23611265

RESUMO

OBJECTIVE: To study the clinicopathologic features and differential diagnosis of proximal gastric mucosa and mucosa of Barrett's esophagus (BE) in biopsy specimens. METHOD: Thirty-eight cases of Barrett's esophagus (diagnosed using WHO criteria) and 44 cases of proximal gastric mucosa were studied by immunohistochemistry (for CK7, CK20, CK4, CK8, S-100 protein, MUC6, COX2 and bcl-2) and fluorescence in-situ hybridization (FISH) (for hTERC gene). The pathologic features were analyzed. RESULTS: The differences in expression of CK7, CK20, MUC6, COX2 and bcl-2 between BE and proximal gastric mucosa with intestinal metaplasia were not statistically significant (P > 0.05). There was however a statistically significant difference in expression of S-100 protein (P < 0.05). The expression of CK7/CK4 and CK7/CK8 in BE showed positive correlation (P < 0.05). However, such correlation was not demonstrated in proximal gastric mucosa (P > 0.05). The results of hTERC gene expression by FISH showed a statistically significant difference between the two groups: 57.9% (22/38) in BE and 13.6% (6/44) in proximal gastric mucosa (P < 0.05). CONCLUSIONS: The significance of CK7 and CK20 expression is uncertain in the differential diagnosis between BE and proximal gastric mucosa. On the other hand, positivity for CK7/CK4/CK8 may support the diagnosis of BE and play a role in distinguishing between the two groups. S-100 protein expression and detection of hTERC gene amplification also contribute to the diagnosis of BE.


Assuntos
Esôfago de Barrett/patologia , Amplificação de Genes , RNA/genética , Proteínas S100/metabolismo , Telomerase/genética , Esôfago de Barrett/genética , Esôfago de Barrett/metabolismo , Mucosa Gástrica/metabolismo , Mucosa Gástrica/patologia , Humanos , Imuno-Histoquímica , Hibridização in Situ Fluorescente , Queratina-20/metabolismo , Queratina-4/metabolismo , Queratina-7/metabolismo , Queratina-8/metabolismo , Metaplasia/genética , Metaplasia/metabolismo , Metaplasia/patologia , Estudos Retrospectivos
16.
Zhonghua Bing Li Xue Za Zhi ; 39(7): 447-51, 2010 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-21055172

RESUMO

OBJECTIVE: To study the serrated lesions of colon and to compare the malignant potential between traditional serrated adenomas (TSA) and conventional adenomas (CAD). METHODS: A total of 5347 cases of colorectal polyps encountered in five regional hospitals during a five-year period were retrospectively reviewed. The serrated lesions were classified on the basis of histologic examination. One hundred and eighty-seven cases of CAD (including 160 cases of tubular adenoma and 27 cases of villous adenoma) and 36 cases of invasive adenocarcinoma were randomly selected as the controls. The degree of dysplasia and expressions of Ki-67, p53 and beta-catenin in TSA and CAD were compared. RESULTS: Amongst the 5347 colorectal polyps studied, 258 cases (4.8%) of serrated lesions were found, which included 112 cases (43.4%, 112/258) of hyperplastic polyp, 78 cases (30.2%, 78/258) of TSA and 26 cases (10.1%, 26/258) of sessile serrated adenoma. Sixty-two cases of TSA were identified from 3 hospitals, in which moderate dysplasia was found in 13 cases. High-grade intraepithelial neoplasia and ICA were found in 6 cases (9.6%). Compared with the 187 cases of CAD, moderate dysplasia were found in 27 cases and high-grade intraepithelial neoplasia and invasive adenocarcinoma were found in 25 cases (13.3%, χ(2) = 19.373, P = 0.000). There was statistically significant difference between TSA and CAD in the degree of dysphasia. The expression of Ki-67, p53 and beta-catenin in TSA and CAD showed no significant difference (P > 0.05). CONCLUSIONS: The incidence of serrated lesions is lower in northern Chinese population than that in Caucasians. TSA has obvious malignant potential; but the rate associated with high-grade intraepithelial neoplasia and invasive adenocarcinoma is lower than that in CAD.


Assuntos
Adenoma/patologia , Transformação Celular Neoplásica/patologia , Neoplasias Colorretais/patologia , Pólipos Intestinais/patologia , Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Adenoma/classificação , Adenoma/metabolismo , Adenoma Viloso/classificação , Adenoma Viloso/metabolismo , Adenoma Viloso/patologia , Pólipos do Colo/metabolismo , Pólipos do Colo/patologia , Neoplasias Colorretais/classificação , Neoplasias Colorretais/metabolismo , Humanos , Pólipos Intestinais/metabolismo , Antígeno Ki-67/metabolismo , Lesões Pré-Cancerosas/metabolismo , Lesões Pré-Cancerosas/patologia , Reto/patologia , Estudos Retrospectivos , Proteína Supressora de Tumor p53/metabolismo , beta Catenina/metabolismo
18.
Zhonghua Nei Ke Za Zhi ; 48(5): 402-5, 2009 May.
Artigo em Chinês | MEDLINE | ID: mdl-19615160

RESUMO

OBJECTIVE: To verify the traditional serrated pathway by comparing microsatellite instability (MSI) status among traditional serrated adenoma, traditional adenoma, serrated colorectal cancer and non-serrated colorectal cancer. METHODS: Seventy-five paraffin-embedded tissue samples, including 15 with serrated adenocarcinoma (Sca), 20 with non-serrated adenocarcinoma (N-Sca), 20 with traditional serrated adenoma (TSA) and 20 with villous adenoma (AD) were collected from the pathology department of our hospital. Genomic DNA was extracted from these samples and then amplified with fluorescently-labeled primer specific for BAT25 and BAT26. The MSI status was detected with DNA automatic sequencer. RESULTS: Six of 18 samples with TSA harbored MSI-H and twelve MSI-L/MSS; 18 samples with conventional adenoma were exclusively of MSS; 3 of 13 samples of serrated carcinoma harbored MSI-H and ten MSI-L/MSS; 18 of 19 N-Sca samples harbored MSI-L/MSS and only one MSI-H. With Chi-square test, the MSI frequency in AD group and N-Sca group was significantly lower than that in TSA group and Sca group (P<0.05); but with no statistical difference between the TSA group and Sca groups (P>0.05). CONCLUSION: MSI-H frequency in AD group and N-Sca group was obviously lower than that of TSA group and Sca group. It is concluded that there might be a new traditional serrated neoplasia pathway which is different from the conventional adenoma-carcinoma carcinogenesis pathway, but we still need prospective follow-up studies to verify its existence.


Assuntos
Adenoma Viloso/genética , Neoplasias Colorretais/genética , Instabilidade de Microssatélites , Adenoma Viloso/patologia , Adulto , Idoso , Neoplasias Colorretais/patologia , Ilhas de CpG , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
20.
Zhonghua Bing Li Xue Za Zhi ; 38(2): 100-5, 2009 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-19573354

RESUMO

OBJECTIVE: To study the clinicopathologic features and proliferative status of colorectal hyperplastic polyp (HP), sessile serrated adenoma (SSA) and traditional serrated adenoma (TSA). METHODS: One hundred and four cases colorectal serrated lesions were collected from 2628 cases of colorectal polyps during the period from November, 2002 to December, 2007. The clinicopathologic features and expression of proliferation marker Ki-67 were studied. RESULTS: On the basis of morphologic examination, 60 cases were classified as HP, 20 cases as TSA, 11 cases as SSA, 7 cases as mixed HP/SSA/TSA, and 6 cases as mixed serrated polyp/adenoma and tubular adenoma. Immunohistochemical study for Ki-67 showed that 40 cases (78%) of the 51 cases of HP were either mostly negative or rarely (<25% cells) positive. Most of the positive cells were located at crypt bases. Among the 15 cases of TSA, 11 of them revealed positive cryptal cells (25% to 50% or>50% positivity). Most of the positive cells were located in mid portion of crypts. The number and distribution of Ki-67 positive cells in SSA were similar to those in TSA but were significantly different from those in tubular adenoma and adenocarcinoma (chi2=34.601, P=0.000; chi2=63.077, P=0.000, respectively). CONCLUSIONS: HP, SSA and TSA have their morphologic characteristics, with some overlapping features noted. The distinction between SSA and HP can be difficult. Diagnosis of SSA relies mostly on architectural rather than cytologic features. The distinction between TSA and SSA depends mainly on the presence of dysplasia. Ectopic crypt formation is almost exclusively seen in TSA. The distribution and percentage of Ki-67-positive cells are also helpful in subtyping of various colorectal serrated lesions. In general, the proliferative index is lower in serrated adenoma (TSA or SSA) than in tubular adenoma.


Assuntos
Adenoma/patologia , Neoplasias Colorretais/patologia , Pólipos Intestinais/patologia , Antígeno Ki-67/metabolismo , Adenocarcinoma/patologia , Adenoma/metabolismo , Adenoma Viloso/metabolismo , Adenoma Viloso/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Proliferação de Células , Neoplasias Colorretais/metabolismo , Diagnóstico Diferencial , Feminino , Humanos , Pólipos Intestinais/metabolismo , Masculino , Pessoa de Meia-Idade , Adulto Jovem
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