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1.
J Nanobiotechnology ; 21(1): 407, 2023 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-37924105

RESUMO

Rapid hemostasis of uncontrolled bleeding following traumatic injuries, especially accompanied by coagulopathies, remains a significant clinical challenge. Extracellular vesicles (EVs) show therapeutic effects for fast clotting. However, low yield, specific storage conditions, and lack of proper carriers have hindered EVs' clinical application. Herein, we establish an optimized procedure method to generate lyophilized mesenchymal stem cell-derived apoptotic vesicles (apoVs) with adhesive hydrogel sponge to show superior procoagulant activity for traumatic hemorrhage. Mechanistically, apoVs' procoagulant ability stems from their high tissue factor (TF) and phosphatidylserine (PS) expression independent of hemocytes and circulating procoagulant microparticles (cMPs). Their stable hemostatic capability was maintained after 2-month room temperature storage. Subsequently, we mixed apoVs with both phenylboronic acid grafted oxidized hyaluronic acid (PBA-HA) and poly(vinyl alcohol) (PVA) simultaneously, followed by lyophilization to construct a novel apoV-encapsulated hydrogel sponge (apoV-HS). Compared to commercial hemostats, apoV-HS exhibits rapid procoagulant ability in liver-laceration and femoral artery hemorrhage in rat and rabbit models of coagulopathies. The combination of high productivity, physiological stability, injectability, plasticity, excellent adhesivity, biocompatibility, and rapid coagulant property indicates that apoV-HS is a promising therapeutic approach for heavy hemorrhage in civilian and military populations.


Assuntos
Vesículas Extracelulares , Hemostáticos , Ratos , Animais , Coelhos , Adesivos , Hidrogéis , Hemostáticos/farmacologia , Hemorragia/tratamento farmacológico
2.
Histol Histopathol ; : 18665, 2023 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-37750664

RESUMO

OBJECTIVE: Head and neck squamous cell carcinoma (HNSCC) is a histological type of cancer originating from the head and neck. Selenium complexes have been considered as a potential treatment for HNSCC. Therefore, the present work focused on probing the mechanism of L-selenomethionine (SeMet) in HNSCC treatment. METHODS: MTT and colony formation assays were carried out to analyze the survival rate and proliferation of HNSCC cells, respectively. TUNEL staining was performed to examine apoptosis of HNSCC cells. Additionally, qRT-PCR and Western blotting assays were performed to measure mRNA and protein levels, separately. RESULTS: SeMet treatment significantly hindered the survival and promoted the apoptosis of HNSCC cells in a dose- and time-dependently. SeMet administration promoted expression of TopBP1, ATR, H2AX, p-ATR and γ-H2AX, and suppressed that of TCAB1. Importantly, SeMet treatment suppressed the proliferation and facilitated the apoptosis of HNSCC cells, which were partly reversed by down-regulation of TopBP1 or up-regulation of TCAB1. The activation of SeMet to TopBP1/ATR signaling was rescued by TCAB1 up-regulating, and the inhibition of SeMet to TCAB1 expression was rescued by TopBP1 silencing. CONCLUSION: Our findings show that SeMet inhibits the proliferation of HNSCC cells and promotes their apoptosis by targeting TopBP1/ATR and TCAB1 signaling. SeMet is a potential method for HNSCC treatment.

3.
Scand J Clin Lab Invest ; 82(7-8): 576-580, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36336351

RESUMO

The objective of this study was to clinically and genetically characterize a pedigree with Liddle syndrome (LS). A LS pedigree comprising with one proband and seven family members was enrolled. The subjects' symptoms, laboratory results and genotypes were analyzed. Peripheral venous samples were collected from the subjects, and genomic DNA was extracted. DNA library construction and exome capture were performed on an Illumina HiSeq 4000 platform. The selected variant sites were validated using Sanger sequencing. The mutation effects were investigated using prediction tools. The proband and her paternal male family members had mild hypertension, hypokalemia and muscle weakness, including the absence of low renin and low aldosterone. Genetic analysis revealed that the proband carried a compound heterozygous mutation in SCNN1A, a novel heterozygous mutation, c.1130T > G (p.Ile377Ser) and a previously characterized polymorphism, c.1987A > G (p.Thr633Ala). The novel mutation site was inherited in an autosomal dominant manner and was predicted by in silico tools to exert a damaging effect. Alterations in the SCNN1A domain were also predicted by protein structure modeling. After six months of follow-up, treatment had significantly improved the patient's limb weakness and electrolyte levels. The novel mutation c.1130T > G of the SCNN1A gene was detected in the pedigree with LS. The clinical manifestations of the pedigree were described, which expand the phenotypic spectrum of LS. This result of this study also emphasizes the value of genetic testing for diagnosing LS.


Assuntos
Hipertensão , Hipopotassemia , Síndrome de Liddle , Feminino , Humanos , Masculino , Hipopotassemia/genética , Canais Epiteliais de Sódio/genética , Canais Epiteliais de Sódio/uso terapêutico , Hipertensão/genética , Síndrome de Liddle/diagnóstico , Síndrome de Liddle/tratamento farmacológico , Síndrome de Liddle/genética , Mutação , Linhagem
4.
Chemosphere ; 303(Pt 2): 135184, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35654237

RESUMO

The LaMnO3 catalysts doped with transition metal (Zr, Co, Fe) were prepared. The influencing factors (the catalyst type, the initial concentration, the gas flow, and oxygen content) on the degradation efficiency by the non-thermal plasma synergistic the LaMnO3 catalysts doped with Zr, Co and Fe were investigated systematically. The degradation mechanism of the meta-xylene degradation by the non-thermal plasma synergistic Mn-Zr-La/Al2O3 was researched. The results showed that the Mn-Zr-La/Al2O3 catalyst in the four catalysts had the best degradation efficiency for meta-xylene, which was 99.6% at the applied voltage of 44 kV. The by-product ozone concentration was low, and the NOx was not detected. Meanwhile, the XPS characterization analysis study revealed that the proportion of Mn4+ element and the proportion of Osur in the Zr-doped Mn-Zr-La/Al2O3 catalyst were both the highest. The degradation efficiency decreased with the increasing of the initial concentration and gas flow, but first increased and then decreased with the increasing of oxygen content. The fresh and used Mn-Zr-La/Al2O3 were characterized by SEM, XRD, BET, FT-IR, O2-TPD, and the tail gas was treated by GC-MS. Then synergistic degradation mechanism for the meta-xylene by the non-thermal plasma over the Mn-Zr-La/Al2O3 catalyst are proposed.


Assuntos
Ozônio , Catálise , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura , Xilenos
5.
Sensors (Basel) ; 21(15)2021 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-34372486

RESUMO

Flying safely in complex urban environments is a challenge for unmanned aerial vehicles because path planning in urban environments with many narrow passages and few dynamic flight obstacles is difficult. The path planning problem is decomposed into global path planning and local path adjustment in this paper. First, a branch-selected rapidly-exploring random tree (BS-RRT) algorithm is proposed to solve the global path planning problem in environments with narrow passages. A cyclic pruning algorithm is proposed to shorten the length of the planned path. Second, the GM(1,1) model is improved with optimized background value named RMGM(1,1) to predict the flight path of dynamic obstacles. Herein, the local path adjustment is made by analyzing the prediction results. BS-RRT demonstrated a faster convergence speed and higher stability in narrow passage environments when compared with RRT, RRT-Connect, P-RRT, 1-0 Bg-RRT, and RRT*. In addition, the path planned by BS-RRT through the use of the cyclic pruning algorithm was the shortest. The prediction error of RMGM(1,1) was compared with those of ECGM(1,1), PCGM(1,1), GM(1,1), MGM(1,1), and GDF. The trajectory predicted by RMGM(1,1) was closer to the actual trajectory. Finally, we use the two methods to realize path planning in urban environments.


Assuntos
Algoritmos
6.
Chemosphere ; 226: 766-773, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30965247

RESUMO

A new reactor of array double dielectric barrier discharge (DDBD) combined with catalysis was prepared, and the effect of different factors on removal efficiency of toluene at pilot scale were investigated. The possible degradation mechanism was explored. The results indicate that the removal efficiency of toluene in the exhaust gas decreases with the increasing of the toluene initial concentration and the gas flow rate, but increases with the increasing of the specific energy density. When the air relative humidity is 55%, the removal efficiency of toluene is higher than that of the relative humidity by 85%. The results of XPS, FT-IR and GC-MS analysis show that the main intermediate products of removing toluene by DDBD combined with TiO2/Al2O3 catalyst are phenol, benzaldehyde, benzyl alcohol, benzoic acid, N-benzyl formamide, dimethyl terephthalate, dimethyl isophthalate and other substances. There are five possible pathways to degrade toluene by DDBD combined with TiO2/Al2O3.


Assuntos
Óxido de Alumínio/química , Eletroquímica/métodos , Titânio/química , Tolueno/isolamento & purificação , Catálise , Gases/análise , Gases em Plasma/análise , Dados Preliminares , Análise Espectral
7.
Heart Fail Rev ; 24(3): 335-342, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30610455

RESUMO

Cardiac resynchronization therapy (CRT) has been established to improve prognosis for patients with heart failure and SR. Whether the benefit observed with CRT on survival was similar in AF patients receiving atrio-ventricular junction ablation (AVJA) or not and patients in SR remains uncertain. The primary purpose of this study was to comprehensively evaluate the impact of CRT on the outcome of survival in atrial fibrillation (AF) patients with or without AVJA and patients in sinus rhythm (SR). Medline, Embase, and the Cochrane Library were searched for inception through June 31, 2018. Two reviewers independently evaluated and extracted data from 4 studies, including a total of 7896 CRT recipients, composed of 554 AF with AVJA (CRT+AF+AVJA), 1071 AF without AVJA (CRT+AF-AVJA), and 6244 SR (CRT+SR). The benefit on survival was comparable between CRT+AF+AVJA and CRT+SR (HR = 1.00; 95% CI, 0.73-1.40). CRT+AF+AVJA and CRT+SR both were associated with significantly higher survival compared with CRT+AF-AVJA, with hazard ratio of 0.64 (95% CI, 0.46-0.91) and 0.63 (95% CI, 0.53-0.75), respectively. The survival benefit was similar for patients with CRT+AF+AVJA and CRT+SR, while it was 36-37% high as compared to CRT+AF-AVJA. Whether aggressive intervention with AVJA in AF should be routinely combined with CRT despite rate-slowing drug treatment is helpful deserves further studies.


Assuntos
Terapia de Ressincronização Cardíaca/mortalidade , Ablação por Cateter , Insuficiência Cardíaca/terapia , Síndrome do Nó Sinusal/terapia , Idoso , Idoso de 80 Anos ou mais , Fibrilação Atrial , Feminino , Insuficiência Cardíaca/mortalidade , Humanos , Masculino , Pessoa de Meia-Idade , Metanálise em Rede , Estudos Observacionais como Assunto , Prognóstico , Síndrome do Nó Sinusal/mortalidade , Taxa de Sobrevida , Resultado do Tratamento
8.
BMC Cardiovasc Disord ; 17(1): 127, 2017 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-28521773

RESUMO

BACKGROUND: About 10-15% patients who take statins experience skeletal muscle problems. Red yeast rice has a good safety profile could provide a compromise therapeutic strategy. Therefore, the aim of this study was to evaluate the effects of red yeast rice, when compared to simvastatin, on the muscle fatigue symptom and the serum lipid level in dyslipidemic patients with low to moderate cardiovascular risk. METHODS: A total of 60 dyslipidemic patients with low to moderate cardiovascular risk were recruited and randomly assigned to receive either simvastatin (n = 33) or red yeast rice (n = 27) for 4 weeks. The muscle fatigue score, the physical activity, the serum lipid profile and the safety profile were then evaluated. RESULTS: At the end of study, the fatigue score was significantly increased in patients treated with simvastatin, whereas no significant change was observed in patients receiving red yeast rice. In addition, the physical activity level was significantly decreased in patients from simvastatin group when compared to those from red yeast rice group. Similar lipid-lowering effects were observed in two groups. The safety profile was not affected after the treatments. CONCLUSIONS: Among dyslipidemic patients with low to moderate cardiovascular risk, red yeast rice induced less fatigue side effect and exerted comparable lipid-lowering effects when compared to simvastatin in this pilot primary prevention study. TRIAL REGISTRATION: NCT01686451 .


Assuntos
Produtos Biológicos/uso terapêutico , Suplementos Nutricionais , Dislipidemias/tratamento farmacológico , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Lipídeos/sangue , Fadiga Muscular/efeitos dos fármacos , Músculo Esquelético/efeitos dos fármacos , Sinvastatina/uso terapêutico , Adulto , Produtos Biológicos/efeitos adversos , Biomarcadores/sangue , China , Suplementos Nutricionais/efeitos adversos , Dislipidemias/sangue , Dislipidemias/diagnóstico , Feminino , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/efeitos adversos , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/fisiopatologia , Projetos Piloto , Sinvastatina/efeitos adversos , Fatores de Tempo , Resultado do Tratamento
10.
Bioresour Technol ; 102(3): 2985-9, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21030253

RESUMO

The effects of pH, temperature and sucrose addition on biodegradative capacity of Fusarium sp. HJ01 for 4-chlorophenol (4-CP) were examined, the property of dioxygenases produced by Fusarium sp. HJ01 during 4-CP degradation was investigated. The results show that Fusarium sp. HJ01 has a high capacity on degrading 4-CP in solution. The optimum values of pH, sucrose concentration and temperature are pH 7,1 g/L and 30°C, respectively. The strain can produce chlorocatechol 1,2-dioxygenase (CC12O) and chlorocatechol 2,3-dioxygenase (CC23O), which show the highest activities when 4-CP is used as the sole carbon source and energy, and the optimal values of pH and temperature are pH 7 and 50°C for CC12O as well as pH 8 and 60°C for CC23O. The kinetics of enzyme-catalyzed reactions accord with the Michaelis-Menten equation. To our knowledge, this is the first study on biodegradation of 4-CP by Fusarium sp. HJ01.


Assuntos
Catecol 1,2-Dioxigenase/metabolismo , Clorofenóis/metabolismo , Dioxigenases/metabolismo , Fusarium/classificação , Fusarium/metabolismo , Biodegradação Ambiental , Ativação Enzimática , Especificidade da Espécie
11.
J Hazard Mater ; 165(1-3): 950-4, 2009 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-19054611

RESUMO

A novel Streptomyces sp. HJ02 can grow using pyridine as only carbon resource and has strong ability of pyridine degradation. The effect of pH, temperature, concentration of pyridine and sucrose addition on biodegradative capacity of Streptomyces sp. HJ02 was examined. The main metabolism pathways and mechanism of pyridine degradation by HJ02 strain were described. The Streptomyces sp. HJ02 degraded 2000 mg/l of pyridine nearly within 8 days. The glucose added in culture inhibited on activity of both SSD and amidase. These two enzymes can act and retain its catalytic ability over wide ranges of temperature and pH. The SSD had a higher activity in alkalescence condition from pH 7.0 to pH 10.0 and was more stable at elevated temperatures from 25 degrees C to 40 degrees C. This strain exhibited both succinate semialdehyde dehydrogenase (EC 1.2.1.24) (SSD) and amidase in free cell extracts obtained from cells grown exclusively on pyridine or with sucrose added, suggesting that the metabolism of pyridine was ripped between C-2 and C-3, and pyridine was hydrolyzed to succinate semialdehyde and formamide.


Assuntos
Biodegradação Ambiental , Piridinas/metabolismo , Streptomyces/metabolismo , Amidoidrolases/metabolismo , Carbono/metabolismo , Concentração de Íons de Hidrogênio , Hidrólise , Redes e Vias Metabólicas , Temperatura
12.
Zhongguo Zhong Yao Za Zhi ; 33(5): 544-9, 2008 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-18536380

RESUMO

OBJECTIVE: To study the effects of puerarin on pulmonary Vascular remodeling in rats with pulmonary hypertension induced by chronic hypoxia and hypercapnia. METHOD: Forty male rats (180-220) g of grade two were randomly divided into five groups: normal control group (NC), hypoxia-hypercapnia 1, 2, 3 week groups (LH1, LH2, LH3) and hypoxia-hypercapnia 3-week + puerarin group (LHP3 group, puerarin intraperitoneal injection, 20 mg x kg(-1) x d(-1)). Collagen I, III and their mRNA were observed in pulmonary arterioles by the technique of immunohistochemistry and in situ hybridization. RESULT: Light microscopy showed media thickness of pulmonary arterioles was much higher in LH3 group than that of NC group, and, vessel cavity turned more straiter in LH3 group than that of NC group. Howerer, the damage of pulmonary arterioles in LHP3 group was much slighter than that of LH3 group. The levels of plasma ET-1 and lung homogenates Hyr and MDA were much higher in rats of LH3 group than those of NC group (P < 0.01), and lower in LHP3 group than LH3 groups (P < 0.01). The activities of SOD in lung homogenates were significantly lowered in hypoxic and hypercapnic groups compared with control group (P < 0.01), but higher in LHP3 group than that of LH3 group. Plasma NO content of group LH was lower than that of group NC (P < 0.01), it was highter in group LHP3 than that of group LH3 (P < 0.01). Expression of collagen I and collagen I mRNA in pulmonary arterioles were significantly higher in rats of LH groups than those of NC group (P < 0.01), and they were lower in rats of LHP3 group than those of LH3 group (P < 0. 01). Expression of collagen III and collagen III mRNA were not significant difference among three groups. CONCLUSION: Puerarin could improve pulmonary vascular remodeling in rats with pulmonary hypertension by inhibiting the deposition of collagen.


Assuntos
Hipercapnia/complicações , Hipertensão Pulmonar/tratamento farmacológico , Hipóxia/complicações , Isoflavonas/farmacologia , Animais , Masculino , Estresse Oxidativo/efeitos dos fármacos , Artéria Pulmonar/efeitos dos fármacos , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley
13.
J Hazard Mater ; 148(1-2): 38-42, 2007 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-17336453

RESUMO

Fusarium sp. HJ01 can grow using phenol as only carbon resource and has strong ability of phenol degradation. The effect of pH, temperature and sucrose addition on biodegradative capacity of Fusarium sp. HJ01 was examined. The main metabolism pathways and mechanism of phenol degradation by HJ01 strain is described. This strain exhibited both cathecol 1,2-dioxygenase (C12) and cathecol 2,3-dioxygenase (C23) in free cell extracts obtained from cells grown exclusively on phenol or with sucrose added, suggesting that the intermediate cathecol can be oxidized in the catabolic pathway of ortho and meta fission. Mineral salts added in culture have an inhibition on both C12 and C23. These two enzymes can act and retain its catalytic ability over wide ranges of temperature and pH. C12 activity was optimal at pH 6.8 and 40 degrees C, with significant activity observed in the range from pH 3 to pH 8.8, and in the temperature range from 30 to 50 degrees C. In comparison with C12, the activity of C23 was slightly more sensitive to pH, C23 had a higher activity in alkalescence condition from pH 7.4 to pH 10.6 and was more stable at higher temperatures from 30 to 75 degrees C.


Assuntos
Biodegradação Ambiental , Fusarium/metabolismo , Fenóis/metabolismo , Concentração de Íons de Hidrogênio , Redes e Vias Metabólicas , Sacarose , Temperatura
14.
Huan Jing Ke Xue ; 28(11): 2642-5, 2007 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-18290497

RESUMO

The sorption curve of cetylpyridinium chloride (CPC) onto bentonite by microwave irradiation was studied. The effects of microwave reaction time and CPC concentration on interlayer spacing and organic carbon content of organobentonite were tested, respectively. Thermodynamics and kinetics of sorption of CPC onto bentonite by microwave irradiation were studied. The saturated adsorption amount of CPC to bentonite with microwave irradiation time from 90 s to 120 s was equal to that of conventional sorption, up to 0.001 63 mol x g(-1). On the condition of microwave irradiation time with 2 min and concentration of CPC with 1.20 mmol x L(-1), the interlayer spacing was attained to 2.44 nm at the best, and organic carbon content was 23.45%. The atomic force microscopy (AFM) showed that the typical layer morphological structure of bentonite was not devastated by microwave. Contrast to conventional sorption, sorption of CPC onto bentonite was greatly influenced by microwave, velocity constant of sorption reaction was increased 107.6 times, and free energy of sorption reaction system was decreased.


Assuntos
Bentonita/química , Cetilpiridínio/química , Micro-Ondas , Poluentes Químicos da Água/química , Adsorção/efeitos da radiação , Cinética , Microscopia de Força Atômica , Tensoativos/química
15.
J Hazard Mater ; 136(2): 251-7, 2006 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-16426750

RESUMO

The microwave enhanced-sorption of dyestuffs such as Neutral Red S-BR, Neutral Dark Yellow GL and Acid Blue B onto organobentonites from water was investigated. The decolorization rates of various dyestuffs by organobentonites were increased from 18.0% to 71.8%, the saturated sorption capacity of Neutral Red S-BR and Acid Blue B were increased 83.9% and 76.3% by microwave irradiation, respectively. The value of the microwave enhanced-sorption parameter R(m) increased in the following order: Neutral Red S-BR>Acid Blue B>Neutral Dark Yellow GL, which corresponded with their aqueous solubility. The zeta potentials of particles were decreased greatly by microwave, which is very significant for improving both sorption of dyestuffs to organobentonites from water and the separation of the adsorbents from treated water.


Assuntos
Bentonita/química , Corantes/química , Micro-Ondas , Poluentes Químicos da Água/isolamento & purificação , Adsorção , Cátions , Cor , Difração de Raios X
16.
Huan Jing Ke Xue ; 27(11): 2212-6, 2006 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-17326428

RESUMO

Microwave-enhanced integrative sorption (MEIS) of dye to mixture of surfactant and bentonite was put forward. The order of factor for integrative method was obtained by the orthogonal experiment. The optimal conditions, properties, kinetics and mechanisms for microwave-enhanced integrative sorption of Neutral Red S-BR to bentonite from water were investigated. Comparative study on decolorization rates of Neutral Red S-BR by other sorption method and MEIS from water were conducted. It is concluded that the order of factor for integrative method is amount of surfactant, bentonite and microwave time. The optimal condition for MEIS is that the ratio of amount of bentonite and water is equal to 1/1 000, the concentration of cetylpyridinium chloride (CPC) is 120 mg/L (equivalent to 28% cation exchange capacity of bentonite) and microwave time is 60s. Comparative with organobentonite, the decolorization rates of Neutral Red S-BR to bentonite are greatly increased by MEIS at higher concentration of dye, amount of surfactant is greatly decreased, and the saturated sorption capacity and the reactive rate of sorption of dye to bentonite are greatly increased by microwave.


Assuntos
Bentonita/química , Corantes/química , Micro-Ondas , Eliminação de Resíduos Líquidos/métodos , Adsorção , Tensoativos/química , Eliminação de Resíduos Líquidos/instrumentação
17.
Zhonghua Jie He He Hu Xi Za Zhi ; 26(7): 403-6, 2003 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-12921644

RESUMO

OBJECTIVE: To investigate the effect of chronic hypoxia-hypercapnia and oxygen inhalation on L-arginine transport in rat pulmonary artery. METHODS: Forty male Sprague-Dawley rats were randomly divided into four groups: normal control group (A), the group of 4-week hypoxia-hypercapnia after 4-week hypoxia (B), the group of 4-week oxygen inhalation (D) 4-week exposure to air (C) after 4-week hypoxia and 4-week hypoxia-hypercapnia. Changes in pulmonary artery L-arginine (L-Arg) transport, nitric oxide synthase (NOS) activity, plasma nitrite (NO(2)/NO(3)) concentration and L-Arg level in rats were measured. RESULTS: (1) The mean pulmonary artery pressure (mPAP) and weight ratio of right ventricle to left ventricle plus septum (RV/LV + S) of B group were higher than those of A group (33% and 35%, respectively, P < 0.01), with the D group lower than C group (24% and 24%, respectively, P < 0.05). (2) At low (0.2 mmol/L) or high (5.0 mmol/L) concentration of L-Arg, the velocity of L-Arg transport in B group was lower than that in A group [(3.04 +/- 0.16 vs 4.62 +/- 0.55) micro mol x g(-1) x min(-1) and (8.12 +/- 0.14 vs 11.24 +/- 1.02) micro mol x g(-1) x min(-1), respectively, P < 0.01], and in D group higher than in C group [(4.30 +/- 0.18 vs 3.80 +/- 0.21) micro mol x g(-1) x min(-1) and [(12.31 +/- 0.65 vs 10.04 +/- 1.28) micro mol x g(-1) x min(-1), respectively, P < 0.01]. (3) The activity of pulmonary artery tNOS and iNOS in B group was significantly higher than that in C group [(3.82 +/- 0.42 vs 2.59 +/- 0.22) micro nmol x g(-1) x min(-1) and (3.07 +/- 0.30 vs 1.62 +/- 0.10) nmol x g(-1) x min(-1) respectively, P < 0.01], but cNOS in B group was lower than that in NC group [(0.75 +/- 0.16 vs 0.93 +/- 0.10) nmol x g(-1) x min(-1), P < 0.01]. The activity of tNOS and cNOS was not significantly different between D group and C group (P > 0.05); However, iNOS was lower in D group than in C group [(1.97 +/- 0.18 vs 2.25 +/- 0.17) nmol x g(-1) x min(-1), P < 0.05]. (4) Plasma NO(2)/NO(3) content of B group was decreased by 21%, compared with C group (P < 0.01); and D group was increased by 89% (P < 0.01), compared with C group. (5) Plasma L-Arg level was not significantly different among the four groups (P > 0.05). CONCLUSION: The L-Arg transport injury of the pulmonary artery might be the key cause for the decrease of nitric oxide generation in rats with chronic hypoxia-hypercapnia induced pulmonary hypertension. Oxygen inhalation was found to improve L-Arg transport in the injured arteries.


Assuntos
Arginina/sangue , Hipercapnia/terapia , Hipóxia/terapia , Oxigenoterapia , Artéria Pulmonar/metabolismo , Animais , Transporte Biológico , Hipercapnia/metabolismo , Hipóxia/metabolismo , Masculino , Óxido Nítrico/fisiologia , Óxido Nítrico Sintase/sangue , Ratos , Ratos Sprague-Dawley
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