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1.
Zhongguo Zhong Yao Za Zhi ; 46(17): 4417-4423, 2021 Sep.
Artigo em Zh | MEDLINE | ID: mdl-34581045

RESUMO

In view of the current inadequate standards for Gleditsiae Spina in the Chinese Pharmacopoeia, this study put forward some new items of the quality standards of Gleditsiae Spina. Thin-layer chromatography(TLC) was performed for identification with the reference substance of taxifolin and the reference material of Gleditsiae Spina as the control. According to the general principles of the Chinese Pharmacopoeia(2020 edition, Vol. 4), the moisture, total ash content, and alcohol-soluble extract of medicinal materials and decoction pieces of Gleditsiae Spina were determined. The content determination method for medicinal materials and decoction pieces of Gleditsiae Spina was established using high-performance liquid chromatography(HPLC), with taxifolin as the quality control index. Based on the determination results of 30 batches of samples of Gleditsiae Spina from different habitats, the draft quality standards of Gleditsiae Spina were developed, which provided suggestions for the revision of the quality standards of Gleditsiae Spina in the Chinese Pharmacopoeia.


Assuntos
Medicamentos de Ervas Chinesas , Cromatografia Líquida de Alta Pressão , Controle de Qualidade , Padrões de Referência
2.
Molecules ; 23(6)2018 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-29843370

RESUMO

We designed a series of novel phenothiazine-1,2,3-triazole hybrids by the molecular hybridization strategy and evaluated their antiproliferative activity against three cancer cell lines (MDA-MB-231, MDA-MB-468 and MCF-7). For the structure-activity relationships, the importance of 1,2,3-triazole and substituents on phenyl ring was explored. Among these phenothiazine-1,2,3-triazole hybrids, compound 9f showed the most potent inhibitory effect against MCF-7 cells, with an IC50 value of 0.8 µM. Importantly, compound 9f could induce apoptosis against MCF-7 cells by regulating apoptosis-related proteins (Bcl-2, Bax, Bad, Parp, and DR5). These potent phenothiazine-1,2,3-triazole hybrids as novel apoptosis inducers might be used as antitumor agents in the future.


Assuntos
Antineoplásicos/síntese química , Proteínas Reguladoras de Apoptose/genética , Neoplasias da Mama/genética , Fenotiazinas/síntese química , Antineoplásicos/química , Antineoplásicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Células MCF-7 , Estrutura Molecular , Fenotiazinas/química , Fenotiazinas/farmacologia , Relação Estrutura-Atividade
3.
Zhongguo Zhong Yao Za Zhi ; 42(11): 2102-2109, 2017 Jun.
Artigo em Zh | MEDLINE | ID: mdl-28822155

RESUMO

The chemical constituents from lipophilic parts in the roots of Angelica dahurica cv. Yubaizhi were studied in this paper. The compounds were separated and purified by repeated column chromatographic methods on silica gel and HPLC, and the chemical structures of compounds were determined by spectral data analyses. Thirty-three compounds were obtained and identified as isoimperatorin (1), imperatorin (2), stigmasterol (3), isooxypeucedanin (4), pabulenol (5), psoralen (6), bergapten (7), isodemethylfuropinarine (8), phellopterin (9), osthenol (10), alloimperatorin (11), xanthotoxin (12), xanthotoxol (13), isopimpinellin (14), alloisoimperatorin (15), ß-sitosterol (16), oxyalloimperatorin (17), pabularinone (18), 5-hydroxy-8-methoxypsoralen (19), columbianetin (20), heracol (21), isogosferol (22), 2″R-neobyakangelicol (23), byakangelicin ethoxide (24), byakangelicin (25), oxypeucedanin hydrate (26), uracil (27), umbelliferone (28), bergaptol (29), demethylfuropinarine (30), isobyakangelicol (31), oxypeucedanin ethanolate (32), heraclenol (33). Among them, compounds 8, 10, 17, 21, and 30 were obtained from the roots of title plant for the first time.


Assuntos
Angelica/química , Cumarínicos/isolamento & purificação , Furocumarinas/isolamento & purificação , Raízes de Plantas/química , Sitosteroides/isolamento & purificação
4.
Polymers (Basel) ; 16(8)2024 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-38675085

RESUMO

A three-dimensional helix geometry unit cell is established to simulate the complex spatial configuration of 3D braided composites. Initially, different types of yarn factors, such as yarn path, cross-sectional shape, properties, and braid direction, are explained. Then, the multiphase finite element method is used to develop a new theoretical calculation procedure based on the unit cell for predicting the impacts of environmental temperature on the thermophysical properties of 3D four-direction carbon/epoxy braided composites. The changing rule and distribution characteristics of the thermophysical properties for 3D four-direction carbon/epoxy braided composites are obtained at temperatures ranging from room temperature to 200 °C. The influences of environmental temperature on the coefficients of thermal expansion (CTE) and the coefficients of thermal conduction (CTC) are evaluated, by which some important conclusions are drawn. A comparison is conducted between theoretical and experimental results, revealing that variations in temperature exert a notable influence on the thermophysical characteristics of 3D four-directional carbon/epoxy braided composites. The theoretical calculation procedure is an effective tool for the mechanical property analysis of composite materials with complex geometries.

5.
Clin Cardiol ; 46(8): 877-885, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37417371

RESUMO

Drug-coated balloons (DCBs) have been used in dialysis patients with arteriovenous fistula (AVF) stenosis, but whether DCBs have advantages over ordinary balloons is still controversial. A meta-analysis was designed to investigate the safety and efficacy of DCBs and common balloons (CBs) in the treatment of AVF stenosis. We searched the PubMed, EMBASE, and China National Knowledge Internet (CNKI) databases for randomized controlled trials that evaluated the comparison of DCB angioplasty versus CB angioplasty for AVF stenosis in dialysis patients and reported at least one outcome of interest. The results showed that the DCB group had a higher first-stage patency rate of the target lesion 6 months [odds ratio, OR = 2.31, 95% confidence interval, CI: (1.69, 3.15), p < .01] and 12 months [OR = 2.09, 95% CI: (1.50, 2.91), p < .01] after surgery. There was no statistically significant difference in all-cause mortality between the two groups at 6 months [OR = 0.85, 95% CI: (0.47, 1.52), p = .58] and 12 months [OR = 0.99, 95% CI: (0.60, 1.64), p = .97]. Compared with CB, DCBs as a new endovascular treatment for AVF stenosis have a higher primary patency rate of target lesions and can delay the occurrence of restenosis. There is no evidence that DCB can increase the mortality of patients.


Assuntos
Angioplastia com Balão , Fístula Arteriovenosa , Humanos , Grau de Desobstrução Vascular , Oclusão de Enxerto Vascular/diagnóstico , Oclusão de Enxerto Vascular/etiologia , Oclusão de Enxerto Vascular/terapia , Constrição Patológica/complicações , Resultado do Tratamento , Materiais Revestidos Biocompatíveis , Fatores de Tempo , Angioplastia com Balão/efeitos adversos , Angioplastia com Balão/métodos , Fístula Arteriovenosa/diagnóstico , Fístula Arteriovenosa/terapia , Fístula Arteriovenosa/complicações , Paclitaxel
6.
Nephrol Dial Transplant ; 26(1): 75-83, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20615908

RESUMO

BACKGROUND: Little information is available regarding the mechanisms involved in cytokine-induced type 1 inositol 1,4,5-trisphosphate receptor (IP(3)R1) expression in human mesangial cells (HMCs) in the occurrence of hepatorenal syndrome (HRS). Over-expression of IP(3)R1 would enhance both IP(3)-binding activity and sensitivity. We hypothesize that it is possible that increased IP(3)R1, induced by TNFα, would lead to increased IP(3) sensitivity in response to a variety of vasoconstrictors, and promote HMC contraction and thus lead to reduced GFP, promoting HRS occurrence and development. METHODS: Quantitative real-time polymerase chain reaction and immunoblot assay were used to examine the effects of TNFα on IP(3)R1 mRNA and protein expression. Several inhibitors of kinases, depletion PKC, over-expression of dominant-negative mutant of PKC and non-radioactive PKC assay were used to examine the mechanism of signal transduction of TNFα-regulated IP(3)R1 in HMCs. RESULTS: TNFα increased IP(3)R1 mRNA and protein expression in HMCs, an effect that was blocked by prolonged incubated chronic PMA, D609, safingol and also by transfection with domain-negative PKCα construct. TNFα activated and promoted autophosphorylation of the PKCα. In addition, both anti-TNFR1 and anti-TNFR2 antibodies blocked TNFα-induced IP(3)R1 protein expression, while only anti-TNFR1 antibodies but not anti-TNFR2 antibodies attenuated TNFα-induced PKCα activity. CONCLUSIONS: TNFα increased the expression of IP(3)R1, and this was mediated, at least in part, through the TNFR1/PC-PLC/PKCα and TNFR2 signalling pathways in HMCs.


Assuntos
Receptores de Inositol 1,4,5-Trifosfato/metabolismo , Células Mesangiais/efeitos dos fármacos , Proteína Quinase C-alfa/metabolismo , Receptores Tipo II do Fator de Necrose Tumoral/metabolismo , Receptores Tipo I de Fatores de Necrose Tumoral/metabolismo , Fator de Necrose Tumoral alfa/farmacologia , Fosfolipases Tipo C/metabolismo , Western Blotting , Cálcio/metabolismo , Células Cultivadas , Síndrome Hepatorrenal/metabolismo , Síndrome Hepatorrenal/patologia , Humanos , Inositol 1,4,5-Trifosfato/metabolismo , Receptores de Inositol 1,4,5-Trifosfato/genética , Células Mesangiais/metabolismo , Proteína Quinase C-alfa/genética , RNA Mensageiro/genética , Receptores Tipo I de Fatores de Necrose Tumoral/genética , Receptores Tipo II do Fator de Necrose Tumoral/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais
7.
Zhong Yao Cai ; 31(2): 196-9, 2008 Feb.
Artigo em Zh | MEDLINE | ID: mdl-18619262

RESUMO

OBJECTIVE: To analyze the constituents of essential oil from different processing drynesses of Radix Angelicae Dahuricae. METHODS: Water steam distillation and GC-MS were used. Relative contents were determined by area. RESULTS: 37 compounds were identified. The constituents of essential oil the constituents from Radix Angelicae Dahuricae by insolation, drying and microwave dryness were similar, but one by dryness after sulfurizing and dryness after perspiring were different. CONCLUSION: Dryness after sulfurizing and dryness after perspiring are not fit for the dryness of Radix Angelicae Dahuricae.


Assuntos
Álcoois/análise , Angelica/química , Óleos Voláteis/isolamento & purificação , Plantas Medicinais/química , Alcanos/análise , Dessecação/métodos , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/isolamento & purificação , Ésteres/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Óleos Voláteis/química , Óleos Voláteis/normas , Raízes de Plantas/química , Controle de Qualidade , Tecnologia Farmacêutica/métodos
8.
J Chromatogr A ; 1165(1-2): 39-44, 2007 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-17698075

RESUMO

HPLC-DAD-MS was utilized to investigate the phytochemical constituents in ethanolic extract of Ananas comosus L. leaves (EEACL) responsible for antidiabetic, antihyperlipidemic and antioxidative effects. Eight phenylpropane diglycerides, together with two hydroxycinnamic acids, three hydroxycinnamoyl quinic acids, four phenylpropane monoglycerides, three flavones and six phenylpropanoid glycosides were detected, and their proposed structures were elucidated based on HPLC retention time, UV and MS profiles. Meanwhile, a new HPLC-DAD-MS method was established for the identification and characterization of phenylpropane diglycerides in natural plants.


Assuntos
Ananas/química , Cromatografia Líquida de Alta Pressão/métodos , Fenóis/isolamento & purificação , Espectrometria de Massas em Tandem/métodos , Fenóis/química , Extratos Vegetais , Folhas de Planta/química
9.
Zhong Yao Cai ; 30(11): 1374-8, 2007 Nov.
Artigo em Zh | MEDLINE | ID: mdl-18323200

RESUMO

OBJECTIVE: To establish HPLC fingerprint analysis for the quality control of processed Radix Angelicae Dahuricae. METHODS: HPLC fingerprint analysis of processed Radix Angelicae Dahuricae was developed Agilent C18 column (250 mm x 4.6 mm, 5 microm) was used, with mixture of acetonitrile and 5% phosphorous acid mobile phase in a gradient mode. The flow rate was 1.0 mL/min. The wavelength of measurement was 254 nm. Fifteen batches of processed Radix Angelicae Dahuricae were determined. RESULTS: The methodological evaluation showed that the method had a good repeatability. CONCLUSION: The method can be used to identify and evaluate the quality of Radix Angelicae Dahuricae conveniently.


Assuntos
Angelica/química , Cromatografia Líquida de Alta Pressão/métodos , Medicamentos de Ervas Chinesas/química , Plantas Medicinais/química , Medicamentos de Ervas Chinesas/isolamento & purificação , Medicamentos de Ervas Chinesas/normas , Raízes de Plantas/química , Controle de Qualidade , Reprodutibilidade dos Testes
10.
Ecol Evol ; 7(24): 10582-10591, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-29299240

RESUMO

Plant δ13C-temperature (δ-T) relation has been established in many systems and is often used as paleotemperature transfer function. However, it is still unclear about the exact contributions of temperature variation to plant 13C discrimination because of covariation between temperature and precipitation (aridity), which reduces confidence in reconstruction of paleoclimate. In this study, we measured carbon isotope composition (δ13C) of 173 samples of C3 perennial herbs from 22 sites across a temperature gradient along the 400 mm isohyet in the farming-pastoral zone of North China. The results showed that precipitation obviously affected the correlations of temperatures and foliar δ13C. After removing the influence of precipitation by analysis of covariance (ANCOVA), a more strongly positive relationship was obtained between site-mean foliar δ13C and annual mean temperature (AMT), with a regression coefficient of 0.1636‰/°C (p = .0024). For widespread species, Artemisia lavandulaefolia and Artemisia capillaries, the slopes (or coefficients) of foliar δ13C and AMT were significantly steeper (larger) than those of foliar δ13C and AMT where the precipitation influence was not excluded, whereas the δ-T coefficients of Polygonum persicaria and Leymus chinensis showed little change across the transect after deducting the precipitation effect. Moreover, the positive relationship between temperature and δ13C over the transect could be explained by soil moisture availability related to temperature. Our results may afford new opportunities for investigating the nature of past climate variability.

11.
Chin J Nat Med ; 15(10): 758-765, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29103461

RESUMO

Stroke remains the third leading cause of death and of adult disability worldwide. Vascular occlusion, followed by ischemic cascade, leads to irreversible tissue injury. Recombinant tissue plasminogen activator is the only FDA approved drug for the current treatment of acute ischemic stroke. However, traditional Chinese medicine has a long history and rich clinical experience in the treatment and rehabilitation of ischemic stroke. Using a classical middle cerebral artery occlusion (MCAO) stroke model, we tested the effectiveness of Yiqihuoxue calm wind (YCW) capsule on neurological function, gross pathology and oxidative stress status in MCAO rats. YCW capsule (3.36 and 6.72 g·kg-1 of crude drug) could significantly lower Longa's score and superoxide dismutase (SOD) level, together with less necrotic cells and infarcted area. In addition to elevated MDA and downregulated iNOS expression, YCW capsule exhibited its neuroprotective effects via free radical scavenging and NO inhibition.


Assuntos
Isquemia Encefálica/tratamento farmacológico , Fármacos Neuroprotetores/administração & dosagem , Acidente Vascular Cerebral/tratamento farmacológico , Animais , Isquemia Encefálica/genética , Isquemia Encefálica/metabolismo , Humanos , Masculino , Malondialdeído/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Acidente Vascular Cerebral/genética , Acidente Vascular Cerebral/metabolismo , Superóxido Dismutase/metabolismo
12.
Diabetes ; 54(5): 1497-505, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15855338

RESUMO

Primary diabetic encephalopathy is a recently recognized late complication of diabetes resulting in a progressive decline in cognitive faculties. In the spontaneously type 1 diabetic BB/Wor rat, we recently demonstrated that cognitive impairment was associated with hippocampal apoptotic neuronal loss. Here, we demonstrate that replacement of proinsulin C-peptide in this insulinopenic model significantly prevented spatial learning and memory deficits and hippocampal neuronal loss. C-peptide replacement prevented oxidative stress-, endoplasmic reticulum-, nerve growth factor receptor p75-, and poly(ADP-ribose) polymerase-related apoptotic activities. It partially ameliorated apoptotic stresses mediated via impaired insulin and IGF activities. These findings were associated with the prevention of increased expression of Bax and active caspase 3 and the frequency of caspase 3-positive neurons. The results show that several partially interrelated apoptotic mechanisms are involved in primary encephalopathy and suggest that impaired insulinomimetic action by C-peptide plays a prominent role in cognitive dysfunction and hippocampal apoptosis in type 1 diabetes. Although these abnormalities were not fully prevented by C-peptide replacement, the findings suggest that this regime will substantially prevent cognitive decline in the type 1 diabetic population.


Assuntos
Apoptose/efeitos dos fármacos , Peptídeo C/farmacologia , Transtornos Cognitivos/prevenção & controle , Cognição/fisiologia , Diabetes Mellitus Tipo 1/psicologia , Hipocampo/patologia , Animais , Caspase 12 , Caspases/efeitos dos fármacos , Caspases/metabolismo , Cognição/efeitos dos fármacos , Diabetes Mellitus Tipo 1/patologia , Modelos Animais de Doenças , Hipocampo/efeitos dos fármacos , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Reação em Cadeia da Polimerase , Estado Pré-Diabético/patologia , Estado Pré-Diabético/psicologia , Ratos , Ratos Endogâmicos BB
13.
Diabetes ; 53(6): 1556-63, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15161761

RESUMO

To explore the molecular abnormalities underlying the degeneration of the node of Ranvier, a characteristic aberration of type 1 diabetic neuropathy, we examined in type 1 BB/Wor and type 2 BBZDR/Wor rats changes in expression of key molecules that make up the nodal and paranodal apparatus of peripheral nerve. Their posttranslational modifications were examined in vitro. Their responsiveness to restored insulin action was examined in type 1 animals replenished with proinsulin C-peptide. In sciatic nerve, the expression of contactin, receptor protein tyrosine phosphatase beta, and the Na(+)-channel beta(1) subunit, paranodal caspr and nodal ankyrin(G) was unaltered in 2-month type 1 diabetic BB/Wor rats but significantly decreased after 8 months of diabetes. These abnormalities were prevented by C-peptide administered to type 1 BB/Wor rats and did not occur in duration- and hyperglycemia-matched type 2 BBZDR/Wor rats. The expression of the alpha-Na(+)-channel subunit was unaltered. In SH-SY5Y cells, only the combination of insulin and C-peptide normalized posttranslational O-linked N-acetylglucosamine modifications and maximized serine phosphorylation of ankyrin(G) and p85 binding to caspr. The beneficial effects of C-peptide resulted in significant normalization of the nerve conduction deficits. These data describe for the first time the progressive molecular aberrations underlying nodal and paranodal degenerative changes in type 1 diabetic neuropathy and demonstrate that they are preventable by insulinomimetic C-peptide.


Assuntos
Peptídeo C/metabolismo , Diabetes Mellitus Tipo 1/complicações , Neuropatias Diabéticas/metabolismo , Degeneração Neural/metabolismo , Doenças do Sistema Nervoso Periférico/metabolismo , Nós Neurofibrosos/metabolismo , Animais , Glicemia/análise , Western Blotting , Peptídeo C/sangue , Peptídeo C/farmacologia , Linhagem Celular Tumoral , Diabetes Mellitus Tipo 1/genética , Neuropatias Diabéticas/etiologia , Neuropatias Diabéticas/fisiopatologia , Hemoglobinas Glicadas/metabolismo , Humanos , Imuno-Histoquímica , Insulina/sangue , Insulina/farmacologia , Degeneração Neural/etiologia , Degeneração Neural/fisiopatologia , Condução Nervosa/efeitos dos fármacos , Doenças do Sistema Nervoso Periférico/etiologia , Doenças do Sistema Nervoso Periférico/fisiopatologia , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , Ratos , Ratos Endogâmicos BB , Nervo Isquiático/metabolismo
14.
Brain Res ; 1037(1-2): 12-24, 2005 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-15777748

RESUMO

We have previously shown that hippocampal neuronal apoptosis accompanied by impaired cognitive functions occurs in type 1 diabetic BB/Wor rats. To differentiate the contribution by insulin deficiency vs. that by hyperglycemia on neuronal apoptosis, we examined the activities of various apoptotic pathways in hippocampi from type 1 diabetic BB/Wor rats (hyperglycemic and insulinopenic) and type 2 diabetic BBZDR/Wor rats (hyperglycemic and hyperinsulinemic). DNA fragmentation was demonstrated by LM-PCR in type 1 diabetic BB/Wor rats, but was not detectable in duration- and hyperglycemia-matched type 2 BBZDR/Wor rats. Of various apoptotic pathways, Fas activations, 8-OHdG expression, and caspase-12 were demonstrated in type 1 diabetic BB/Wor rats only. In contrast, perturbations of the IGF and NGF systems and PARP activation were demonstrated in type 1 and to a lesser extent in type 2 diabetes. Expressions of Bax and active caspase-3 were significantly increased in type 1, but not in type 2, diabetic rats. These data suggest a lesser apoptogenic stress in type 2 vs. type 1 diabetes. These differences translated into a more profound neuronal loss in the hippocampus of type 1 rats. The results demonstrate that caspase-dependent apoptotic activities dominate in type 1 diabetes, whereas PARP-mediated caspase-independent apoptotic stress is present in both type 1 and type 2 diabetes. The findings suggest that insulin deficiency plays a compounding role to that of hyperglycemia in neuronal apoptosis underpinning primary diabetic encephalopathy.


Assuntos
Diabetes Mellitus Tipo 1/fisiopatologia , Diabetes Mellitus Tipo 2/fisiopatologia , Nefropatias Diabéticas/fisiopatologia , Insulina/fisiologia , Somatomedinas/fisiologia , Animais , Apoptose , Western Blotting , Caspases/fisiologia , Fragmentação do DNA , Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 2/genética , Nefropatias Diabéticas/patologia , Hipocampo/patologia , Hiperglicemia/patologia , Hiperglicemia/fisiopatologia , Imuno-Histoquímica , Marcação In Situ das Extremidades Cortadas , Insulina/sangue , Masculino , Neurônios/patologia , Estresse Oxidativo/fisiologia , Poli(ADP-Ribose) Polimerases/metabolismo , Ratos , Ratos Endogâmicos BB , Ratos Wistar , Receptores Proteína Tirosina Quinases/metabolismo , Receptores do Fator de Necrose Tumoral/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Receptor fas/metabolismo
15.
Brain Res ; 946(2): 221-31, 2002 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-12137925

RESUMO

Duration-related cognitive impairment is an increasingly recognized complication of type 1 diabetes. To explore potential underlying mechanisms, we examined hippocampal abnormalities in the spontaneously type 1 diabetic BB/W rat. As a functional assay of cognition, the Morris water maze test showed significantly prolonged latencies in 8-month diabetic rats not present at 2 months of diabetes. These abnormalities were associated with DNA fragmentation, positive TUNEL staining, elevated Bax/Bcl-x(L) ratio, increased caspase 3 activities and decreased neuronal densities in diabetic hippocampi. These changes were not caused by hypoglycemic episodes or reduced weight in diabetic animals. To explore potential mechanisms responsible for the apoptosis, we examined the expression of the IGF system. Western blotting and in situ hybridization revealed significant reductions in the expression of IGF-I, IGF-II, IGF-IR and IR preceding (2 months) and accompanying (8 months) the functional cognitive impairments and the apoptotic neuronal loss in hippocampus. These data suggest that a duration-related apoptosis-induced neuronal loss occurs in type 1 diabetes associated with cognitive impairment. The data also suggest that this is at least in part related to impaired insulin and/or IGF activities.


Assuntos
Apoptose/fisiologia , Diabetes Mellitus Tipo 1/patologia , Hipocampo/patologia , Neurônios/patologia , Animais , Glicemia/metabolismo , Northern Blotting , Western Blotting , Caspase 3 , Caspases/metabolismo , Contagem de Células , Transtornos Cognitivos/psicologia , Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 1/psicologia , Hipocampo/metabolismo , Hibridização In Situ , Marcação In Situ das Extremidades Cortadas , Insulina/sangue , Masculino , Aprendizagem em Labirinto/fisiologia , Condução Nervosa/fisiologia , Neurônios/metabolismo , Ratos , Ratos Endogâmicos BB , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Somatomedinas/metabolismo
16.
Eur J Pharmacol ; 490(1-3): 187-97, 2004 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-15094085

RESUMO

Diabetes is an increasingly common disorder which causes and contributes to a variety of central nervous system (CNS) complications which are often associated with cognitive deficits. There appear to be two types of diabetic encephalopathy. Primary diabetic encephalopathy is caused by hyperglycemia and impaired insulin action, which evolves in a diabetes duration-related fashion and is associated with apoptotic neuronal loss and cognitive decline. This appears to be particularly associated with insulin-deficient diabetes. Secondary diabetic encephalopathy appears to arise from hypoxic-ischemic insults due to underlying microvascular disease or as a consequence of hypoglycemia. This type of cerebral diabetic complication is more common in the type 2 diabetic population. Here, we will review the clinical and experimental data supporting this conceptual division of diabetic CNS complications and discuss the underlying metabolic, molecular, and functional aberrations.


Assuntos
Peptídeo C/metabolismo , Doenças do Sistema Nervoso Central/complicações , Complicações do Diabetes , Hiperglicemia/complicações , Insulina/metabolismo , Animais , Apoptose , Doenças do Sistema Nervoso Central/patologia , Doenças do Sistema Nervoso Central/fisiopatologia , Cognição/fisiologia , Diabetes Mellitus/metabolismo , Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 1/metabolismo , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/metabolismo , Humanos
17.
Life Sci ; 76(3): 249-62, 2004 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-15531378

RESUMO

The aim of this study is to explore the mechanism by which diabetes exaggerates cerebral stroke and its outcome. Since ischemia can be related to not only necrosis but apoptosis as well, we compared the development of apoptosis in STZ-diabetic rats and STZ-diabetic rats subjected to occlusion of the middle cerebral artery (MCA). 24-48 hr following MCA occlusion the animals were killed, the brain removed and prepared for evaluation by several indexes of apoptosis: nucleosomal DNA fragmentation, TUNEL staining, activation of caspase-3 and alteration in the expression of Bax and Bcl2. DNA fragmentation was not detected in the cortex of normal and diabetic animals, but was evident following MCA occlusion in diabetic rats. Bax expression was increased in the cortex of normal rats following MCA occlusion and this expression was further increased in the cortex of MCA occluded diabetic rats. Bcl2 expression was not changed in any of the groups. In the hippocampus, DNA fragmentation was not evident in control rats but was observed in diabetic rats. Ischemic injury did not enhance DNA laddering in diabetic animals. The expression of Bax was increased in diabetic rats but was not increased following MCA occlusion. Bcl2 expression was not changed by ischemia in any of the animal models. These data suggest that diabetes may enhance the development of stroke via increased cortical apoptotic activity but this was not additive in the hippocampus following ischemic injury.


Assuntos
Apoptose/fisiologia , Isquemia Encefálica/patologia , Córtex Cerebral/patologia , Diabetes Mellitus Experimental/patologia , Animais , Isquemia Encefálica/complicações , Caspase 3 , Caspases/biossíntese , Caspases/sangue , Córtex Cerebral/metabolismo , Fragmentação do DNA , Diabetes Mellitus Experimental/induzido quimicamente , Diabetes Mellitus Experimental/complicações , Modelos Animais de Doenças , Marcação In Situ das Extremidades Cortadas , Masculino , Artéria Cerebral Média/lesões , Artéria Cerebral Média/patologia , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Ratos , Ratos Endogâmicos F344 , Proteína X Associada a bcl-2
18.
Huan Jing Ke Xue ; 35(4): 1304-10, 2014 Apr.
Artigo em Zh | MEDLINE | ID: mdl-24946580

RESUMO

The present study explored phosphorus fractions in sediments with the growth of Vallisneria natans. Sediment samples in different layers were collected at 20, 50 and 80 d, and vertical change of several phosphorus fractions were measured in the samples. The root distributions and biomass of the V. natans were measured. Our results showed that roots were distributed between 0 and 14 cm in the experimental device. The average number of roots and average root length were 58 and 5.86 cm. After 80 days growth, the percentage of V. natans root biomass were 45.99%, 32.75%, 16.03% and 5.23% in the sediment with depths of 0-3, 4-6, 7-10 and 11-14 cm. Total phosphorus (TP) content, phosphorus extracted by NaOH (NaOH-P), and organic phosphorus (OP) levels remarkably decreased (P < 0.05) in the area with a high concentration of tape grass roots. The content of phosphorus extracted by HCl (HCl-P), and inorganic phosphorus (IP), showed no significant difference (P > 0.05). The results suggest that V. natans root affects the migration and transformation of phosphorus species in the sediment.


Assuntos
Sedimentos Geológicos/química , Hydrocharitaceae/crescimento & desenvolvimento , Fósforo/química , Raízes de Plantas/crescimento & desenvolvimento , Biomassa , Monitoramento Ambiental , Lagos
19.
Huan Jing Ke Xue ; 35(2): 577-84, 2014 Feb.
Artigo em Zh | MEDLINE | ID: mdl-24812950

RESUMO

To characterize the distribution of nitrogen in the sediment of Taige south river estuary, column samples of sediments were collected and analyzed in April, 2012. Our results revealed that a synchronized trend existed among the levels of ammonium nitrogen (NH4(+) -N), organic nitrogen (Org-N) and total nitrogen (TN) in the surface layer of sediment. The NH4(+) -N positively correlated with TN and Org-N significantly (P < 0.05) while TN highly significantly correlated with Org-N (P < 0.01). Org-N was the major form of nitrogen, comprising 93.38% of total nitrogen (TN) averagely. Both horizontal and vertical distribution of nitrogen in sediments apparently changed along the distance to stream outlet. In the horizontal dimension in sediments, Org-N and TN decreased progressively as forwarding into the lake in the extending direction of the main stream, while showed a "W"-type fluctuation in the diverged direction away from the main stream. The level of NH4(+) -N decreased rapidly within 100 m to the stream outlet and remained constantly at a lower level beyond 100 m. However, the level of nitrate nitrogen (NO3(-) -N) stabilized within 0-800 m and increased greatly beyond 800 m. In the vertical dimension in sediments, the level of NH4(+) -N increased with increasing depth. As the distance to the stream outlet increasing, the enrichment of NO3(-) -N was enhanced in surface layers rather than in lower subsurface layers. Alternatively, the enrichment of Org-N and TN were reduced in surface layers but enhanced in subsurface layers.


Assuntos
Estuários , Sedimentos Geológicos/análise , Nitrogênio/análise , China , Lagos , Rios
20.
Huan Jing Ke Xue ; 34(11): 4240-50, 2013 Nov.
Artigo em Zh | MEDLINE | ID: mdl-24455930

RESUMO

To investigate the spatial distribution of nitrogen in the sediment from both internal and external sites of Potamogeton malaianus and Limnanthemun nymphoides communities, levels of various forms of nitrogen were quantified in sediment samples collected from Gonghu Bay, the southern region and the intermediate area between East and West mountains of Lake Taihu in June 2012. The results showed that: (1) Within the algae-type region in Gonghu Bay, the contents of organic (Org-N) and total nitrogen (TN) in the internal sediment (0-25 cm) from P. malaianus communities were higher than those of the external sediment, by 38.06% and 25.65%, respectively. (2) In the non-algal region, the contents of TN, Org-N, NH4(+)-N and NO3(-) -N in the internal sediments from P. malaianus communities were lower by 43.29%, 50.78%, 7.09% and 10.86% compared to those in the external sediments; for L. nymphoides communities, the contents of TN, Org-N, NH4(+) -N and NO3(-) -N in the external sediments were lower by 4.65%, 4.63%, 5.01% and 2.76% compared to the internal sediments. These values suggested that the promotion in reducing sedimentary nitrogen was more effective by the P. malaianus community than by the L. nymphoides community. (3) A significant positive correlation (P < 0.05, n = 24) was found between pH and TN within the external sediments and between pH and NO3(-) -N within the internal sediments (P < 0.05, n = 24), while a significant negative correlation (P < 0.05, n = 24) was found between pH and NH4(+)-N of both aquatic plant communities. The redox potential (Eh) was also found to be significantly positively correlated with TN in both the internal and external sediments of P. malaianus communities (GMN, P < 0.01, R = 0.922 8 * *; NMN, P < 0.01, R = 0.827 7 * *; GMW, P < 0.05, R = 0.748 9 *; NMW, P < 0.05, R = 0.663 7 *). It is therefore concluded that the presence of aquatic plant communities could impact the physical and chemical properties of the sediments.


Assuntos
Sedimentos Geológicos/química , Lagos , Nitrogênio/química , Potamogetonaceae/crescimento & desenvolvimento , China
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