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1.
BMC Cardiovasc Disord ; 20(1): 2, 2020 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-31914929

RESUMO

BACKGROUND: To evaluate the association between preoperative exercise and recovery after cardiac surgery. METHODS: Literature comparing preoperative exercise and the control group for patients receiving cardiac surgery was retrieved in multiple databases. Review Manager 5.2 was adopted for meta-analysis, sensitivity analysis and bias analysis. RESULTS: Finally, 6 relevant studies satisfied the inclusion criteria. There was significant difference in length of stay in intensive care unit (ICU) (MD- = 1.35, 95%CI [- 2.64, - 0.06], P = 0.04; P for heterogeneity < 0.0001, I2 = 88%) and physical function after operation (P of heterogeneity = 0.32, I2 = 12%, Z = 9.92, P of over effect< 0.00001). The meta-analysis suggested that there was no significant difference in white blood cell count (WBC) at postoperative day 7 and mental health after operation between the exercise group and the control group. Limited publication bias was observed in this study. CONCLUSION: Preoperative exercise including inhaled muscle training, aerobics, resistance training and stretching could promote recovery after cardiac surgery.


Assuntos
Procedimentos Cirúrgicos Cardíacos , Terapia por Exercício , Cardiopatias/cirurgia , Adulto , Idoso , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Aptidão Cardiorrespiratória , Tolerância ao Exercício , Feminino , Nível de Saúde , Cardiopatias/diagnóstico , Cardiopatias/fisiopatologia , Humanos , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Recuperação de Função Fisiológica , Fatores de Tempo , Resultado do Tratamento
2.
Biochem J ; 474(16): 2785-2801, 2017 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-28706006

RESUMO

Although ancillary pathways of glucose metabolism are critical for synthesizing cellular building blocks and modulating stress responses, how they are regulated remains unclear. In the present study, we used radiometric glycolysis assays, [13C6]-glucose isotope tracing, and extracellular flux analysis to understand how phosphofructokinase (PFK)-mediated changes in glycolysis regulate glucose carbon partitioning into catabolic and anabolic pathways. Expression of kinase-deficient or phosphatase-deficient 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase in rat neonatal cardiomyocytes co-ordinately regulated glycolytic rate and lactate production. Nevertheless, in all groups, >40% of glucose consumed by the cells was unaccounted for via catabolism to pyruvate, which suggests entry of glucose carbons into ancillary pathways branching from metabolites formed in the preparatory phase of glycolysis. Analysis of 13C fractional enrichment patterns suggests that PFK activity regulates glucose carbon incorporation directly into the ribose and the glycerol moieties of purines and phospholipids, respectively. Pyrimidines, UDP-N-acetylhexosamine, and the fatty acyl chains of phosphatidylinositol and triglycerides showed lower 13C incorporation under conditions of high PFK activity; the isotopologue 13C enrichment pattern of each metabolite indicated limitations in mitochondria-engendered aspartate, acetyl CoA and fatty acids. Consistent with this notion, high glycolytic rate diminished mitochondrial activity and the coupling of glycolysis to glucose oxidation. These findings suggest that a major portion of intracellular glucose in cardiac myocytes is apportioned for ancillary biosynthetic reactions and that PFK co-ordinates the activities of the pentose phosphate, hexosamine biosynthetic, and glycerolipid synthesis pathways by directly modulating glycolytic intermediate entry into auxiliary glucose metabolism pathways and by indirectly regulating mitochondrial cataplerosis.


Assuntos
Glucose/metabolismo , Glicólise , Mitocôndrias Musculares/metabolismo , Miócitos Cardíacos/metabolismo , Via de Pentose Fosfato , Fosfofrutoquinase-1 Hepática/metabolismo , Substituição de Aminoácidos , Animais , Animais Recém-Nascidos , Isótopos de Carbono , Células Cultivadas , Meios de Cultura Livres de Soro , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Hexosaminas/metabolismo , Ácido Láctico/metabolismo , Mitocôndrias Musculares/enzimologia , Miócitos Cardíacos/citologia , Miócitos Cardíacos/enzimologia , Oligopeptídeos/genética , Oligopeptídeos/metabolismo , Fosfofrutoquinase-1 Hepática/genética , Mutação Puntual , Pirimidinas/metabolismo , Ácido Pirúvico/metabolismo , Ratos Sprague-Dawley , Proteínas Recombinantes de Fusão/metabolismo , Difosfato de Uridina/análogos & derivados , Difosfato de Uridina/metabolismo
3.
Biochem J ; 467(1): 115-26, 2015 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-25627821

RESUMO

Diabetes is characterized by hyperglycaemia and perturbations in intermediary metabolism. In particular, diabetes can augment flux through accessory pathways of glucose metabolism, such as the hexosamine biosynthetic pathway (HBP), which produces the sugar donor for the ß-O-linked-N-acetylglucosamine (O-GlcNAc) post-translational modification of proteins. Diabetes also promotes mitochondrial dysfunction. Nevertheless, the relationships among diabetes, hyperglycaemia, mitochondrial dysfunction and O-GlcNAc modifications remain unclear. In the present study, we tested whether high-glucose-induced increases in O-GlcNAc modifications directly regulate mitochondrial function in isolated cardiomyocytes. Augmentation of O-GlcNAcylation with high glucose (33 mM) was associated with diminished basal and maximal cardiomyocyte respiration, a decreased mitochondrial reserve capacity and lower Complex II-dependent respiration (P<0.05); however, pharmacological or genetic modulation of O-GlcNAc modifications under normal or high glucose conditions showed few significant effects on mitochondrial respiration, suggesting that O-GlcNAc does not play a major role in regulating cardiomyocyte mitochondrial function. Furthermore, an osmotic control recapitulated high-glucose-induced changes to mitochondrial metabolism (P<0.05) without increasing O-GlcNAcylation. Thus, increased O-GlcNAcylation is neither sufficient nor necessary for high-glucose-induced suppression of mitochondrial metabolism in isolated cardiomyocytes.


Assuntos
Acetilglucosamina/metabolismo , Regulação para Baixo , Glucose/metabolismo , Hiperglicemia/metabolismo , Mitocôndrias Cardíacas/metabolismo , Fosforilação Oxidativa , Processamento de Proteína Pós-Traducional , Aminoacilação , Animais , Animais Recém-Nascidos , Células Cultivadas , Complexo II de Transporte de Elétrons/antagonistas & inibidores , Complexo II de Transporte de Elétrons/metabolismo , Metabolismo Energético , Glucose/efeitos adversos , Mitocôndrias Cardíacas/enzimologia , Miócitos Cardíacos/citologia , Miócitos Cardíacos/enzimologia , Miócitos Cardíacos/metabolismo , N-Acetilglucosaminiltransferases/genética , N-Acetilglucosaminiltransferases/metabolismo , Concentração Osmolar , Ratos Sprague-Dawley , Proteínas Recombinantes/metabolismo , Regulação para Cima , beta-N-Acetil-Hexosaminidases/genética , beta-N-Acetil-Hexosaminidases/metabolismo
4.
Artigo em Zh | MEDLINE | ID: mdl-30130034

RESUMO

Objective: To understand the control status of malaria at hotspots in Yingjiang County and provide measures for malaria elimination in the China-Myanmar border areas of Yunnan Province. Methods: A survey was made in 4 villages with indigenous malaria cases or imported cases in Nabang and Tongbiguan of Yingjiang County in Yunnan Province in June and July 2015. Peripheral blood samples were collected from the neighboring residents around patients and examined by malaria rapid diagnostic test (RDT). The results were further verified by nested-PCR. Mosquitoes were collected by overnight trapping with light traps in Jingpo, Lilisu, Jiema, and Mengxiangyang villages or by human landing catches in Jingpo and Lisu villages. Nested-PCR was performed on part of the captured Anopheles minimus to detect the malaria parasites. Results: One hundred and ninety-four filter blood samples were collected from 11 malaria cases in two sites. All were detected to be negative for Plasmodium by RDT. In contrast, two samples originated from Jingpo and Lisu villages with indigenous cases were detected to be positive for Plasmodium vivax by nested-PCR. A total of 2 374 mosquitoes were captured, belonging to 22 species of 4 genera: Anopheles, Culex, Aedes and Armigeres. The mosquitoes were predominated by genus Culex, followed by genus Anopheles(11.33%, 269/2 374) which was dominated by A. minimus(49.07%, 132/269), then was A. sinensis(4.09%, 11/269), A. maculatus(2.23%, 6/269), A. jeyporiensis(0.74%, 2/269)and so on. The mean indoor man-biting rate of mosquitoes was 5.78 and 3.20 per person per hour for Jingpo and Lisu villages, and the mean outdoor man-biting rate of mosquitoes was 2.30 per person per hour for Lisu Village. The 14 A. minimus were negative for sporozoite infection as detected by nested-PCR. Conclusion: Nested-PCR showed that there are asymptomatic Plasmodium carriers in Yingjiang's border area of Yunnan Province. Four major mosquito species as malaria vectors exist with A. minimus as the dominant one.


Assuntos
Malária , Animais , Anopheles , China , Meio Ambiente , Humanos , Mosquitos Vetores , Plasmodium , Reação em Cadeia da Polimerase , Inquéritos e Questionários
5.
Artigo em Zh | MEDLINE | ID: mdl-26245122

RESUMO

OBJECTIVE: To investigate the resistance level of Culex tritaeniorhynchus to DDT and deltamethrin in Yunnan Province. METHODS: Adult Culex tritaeniorhynchus samples were collected in Zhaoyang District of Zhaotong City, Mangshi County of Dehong Prefecture, Yuanjiang County of Yuxi City, Jiangcheng and Menglian County of Puer City. The susceptibility of Cx. tritaeniorhynchus to DDT and deltamethrin were tested by bioassay method. The resistance level was judged by adjusted mortality. RESULTS: Culex tritaeniorhynchus collected from Zhaoyang, Mangshi, Jiangcheng, Menglian, and Yuanjiang, and exposed to DDT for 1 h, the mortality after 24 hours was 51.1%, 86.8%, 35.4%, 21.0%, and 4.6%, respectively; the resistant grade in Mangshi was maybe resistance(M), and the others 4 sites were resistance (R). The range of KT, to DDT was from 18.76 min to 395.65 min. The mortality of the mosquitoes from the five sites to deltamethrin was 36.9%, 59.2%, 43.1%, 34.1%, and 3.3%, respectively; the resistant grade was R in all sites, and the range of KT50 was 8.69-715.37 min. CONCLUSION: Culex tritaeniorhynchus in Yunnan Province shows simultaneously resistant to DDT and deltamethrin, and therefore the insecticiding strategy should be adjusted.


Assuntos
Culex , Animais , China , DDT , Resistência a Medicamentos , Humanos , Inseticidas , Nitrilas , Piretrinas
6.
Artigo em Zh | MEDLINE | ID: mdl-24822373

RESUMO

From June to August 2012, the blood-sucking mosquitoes were captured around cattle-sheds and human houses in Yuanjiang County, Qiaojia County, Yongshan County, and Jinghong City of Yunan Province. Blood samples from mosquitoes were collected on filter paper. Multiplex PCR assay was used to detect the blood meal samples. Among the 145 mosquitoes captured, 123 were Anopheles sinensis (84.8%) and 22 A. minimus (15.2%). Among the blood samples, corresponding bands were amplified in 134 samples. The result showed that the blood meals were from pigs (n = 104), cows (n = 22), dogs (n = 4), human (n=2), cow and pig (n = 1), pig and human (n = 1). Human blood index of A. sinensis and A. minimus was 0.018 and 0.045, respectively.


Assuntos
Anopheles , Reação em Cadeia da Polimerase Multiplex , Animais , Bovinos , Cães , Humanos , Suínos
7.
Mitochondrial DNA B Resour ; 9(1): 20-23, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38187009

RESUMO

Aureoboletus raphanaceus is a member of boletoid mushroom, which is named after its distinctive radish smell. The mitochondrial genome and phylogenetic relationships with other boletes need to be investigated to gain a comprehensive understanding of it. In this study, we sequenced the mitochondrial genome of A. raphanaceus using next-generation sequencing technology and found that its mitochondrial genome is a circular DNA molecule measuring 42,157 bp. It consists of 15 core protein-coding genes, 27 transfer RNA genes, and two ribosomal RNA genes. The mitochondrial genome had a base composition of A (39.89%), C (11.06%), G (11.67%), and T (37.38%), with a GC content of 22.73%. A phylogenetic tree based on 22 mitochondrial genomes was constructed, which provided the first insights into the phylogenetic relationships of this species with related boletes.

8.
Nat Prod Res ; : 1-9, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38767208

RESUMO

A new lignan phyllanins A (1) and a lignan phyllanins B (2) for which the absolute configuration was determined for the first time, along with four known lignans (3-6) were isolated from the branch and leaf extracts of Phyllanthodendron dunnianum. Their planar structures were mainly determined by a combination of 1D and 2D NMR, HRESIMS spectral analyses, and the absolute configurations of the compounds 1 and 2 were established by DFT GIAO 13C NMR and electronic circular dichroism (ECD) calculations. In addition, all these six lignans were firstly tested for the antibacterial activities against MRSA, Staphylococcus aureus, Enterococcus faecalis, Pseudomonas aeruginosa and Escherichia coli. Among these compounds, 2 and 5 showed potential antibacterial activities against MRSA and S. aureus with MIC values of 4 and 8 µg/mL, respectively.

10.
Mitochondrial DNA B Resour ; 8(10): 1067-1070, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37829256

RESUMO

Lanmaoa macrocarpa is a boletoid mushroom from the family Boletaceae and was named after its relatively larger basidiocarp and bluish color change when bruised. At present, its mitochondrial genome and phylogenetic relationships with other boletes remain unexplored. In this study, we sequenced the mitochondrial genome of L. macrocarpa using next-generation sequencing technology and found that its mitochondrial genome, a circular DNA molecule of 38,139 bp, comprised 15 core protein-coding genes, 26 transfer RNA genes and two ribosomal RNA genes. The mitochondrial genome had a base composition of A (37.05%), C (12.08%), G (11.42%) and T (39.45%) with a GC content of 23.50%. A phylogenetic tree based on 20 mitochondrial genomes was constructed, which revealed the phylogenetic relationships of this species with related boletes for the first time.

11.
Nat Prod Res ; : 1-11, 2023 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-37933750

RESUMO

One new cyclopeptide, cyclo-(L-Trp-L-Phe-L-Phe) (1), one new 2-pyridone derivative, fusarone A (3), and one new natural indole derivative, ethyl 3-indoleacetate (4), along with six known compounds were isolated from the endophytic fungus Fusarium proliferatum T2-10. The planar structures of three new compounds were identified by spectral methods including 1D and 2D NMR techniques, and the absolute configuration of compound 1 was elucidated by Marfey-MS method. In addition, all compounds were evaluated for their cytotoxic and antibacterial activities in vitro. Compound 2 showed remarkable cytotoxic activities against two human hepatoma cell lines SMMC7721 and HepG2 with IC50 values of 5.89 ± 0.74 and 6.16 ± 0.52 µM, and showed moderate antibacterial activities against Staphylococcus aureus and Enterococcus faecalis with MIC values of 7.81 and 15.62 µg/mL, respectively.

12.
Basic Res Cardiol ; 107(6): 305, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23099819

RESUMO

Increased levels of extracellular superoxide dismutase (ecSOD) induced by preconditioning or gene therapy protect the heart from ischemia/reperfusion injury. To elucidate the mechanism responsible for this action, we studied the effects of increased superoxide scavenging on nitric oxide (NO) bioavailability in a cardiac myocyte-specific ecSOD transgenic (Tg) mouse. Results indicated that ecSOD overexpression increased cardiac myocyte-specific ecSOD activity 27.5-fold. Transgenic ecSOD was localized to the sarcolemma and, notably, the cytoplasm of cardiac myocytes. Ischemia/reperfusion injury was attenuated in ecSOD Tg hearts, in which infarct size was decreased and LV functional recovery was improved. Using the ROS spin trap, DMPO, electron paramagnetic resonance (EPR) spectroscopy demonstrated a significant decrease in ROS in Tg hearts during the first 20 min of reperfusion. This decrease in ROS was accompanied by an increase in NO production determined by EPR using the NO spin trap, Fe-MGD. Attenuated ROS in ecSOD Tg myocytes was also supported by decreased production of peroxynitrite (ONOO(-)). Increased NO bioavailability was confirmed by attenuated guanylate cyclase-dependent (p-VASP) signaling. In conclusion, attenuation of ROS levels by cardiac-specific ecSOD overexpression increases NO bioavailability in response to ischemia/reperfusion and protects against reperfusion injury. These findings are the first to demonstrate increased NO bioavailability with attenuation of ROS by direct measurement of these reactive species (EPR, reactive fluorescent dyes) with cardiac-specific ecSOD expression. This is also the first indication that the predominantly extracellular SOD isoform is capable of cytosolic localization that affects myocardial intracellular signal transduction and function.


Assuntos
Traumatismo por Reperfusão Miocárdica/prevenção & controle , Miócitos Cardíacos/enzimologia , Óxido Nítrico/metabolismo , Estresse Oxidativo , Superóxido Dismutase/metabolismo , Animais , Técnicas In Vitro , Camundongos , Camundongos Transgênicos , Infarto do Miocárdio/patologia , Miocárdio/patologia , Espécies Reativas de Oxigênio/metabolismo
13.
Nat Prod Res ; : 1-8, 2022 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-36408983

RESUMO

Two new chromone derivatives (1 and 2), and two known compounds (3 and 4) were isolated from the rhizosphere soil fungus Ilyonectria robusta. Their planar structures and absolute configurations were determined by extensive spectroscopic analysis and electronic circular dichroism (ECD) calculations. Additionally, all the isolated compounds were evaluated for their antibacterial activity against Staphylococcus aureus, Enterococcus faecalis, Pseudomonas aeruginosa and Escherichia coli, but no obvious activity was observed at a concentration of 128 µg/mL.

14.
Nat Prod Res ; : 1-8, 2022 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-36308293

RESUMO

Chemical investigation of an EtOAc extract of the endophytic fungus Pseudocercospora sp. TSS-1 led to the isolation of three new polyketide derivatives, including one benzophenon derivative (1), two spirocyclic polyketides (4 and 5), along with four known compounds (2, 3, 6 and 7). Their structures and the absolute configurations were characterized by means of NMR, HRESIMS, 13C NMR and theoretical electronic circular dichroism calculations. Furthermore, all compounds were evaluated for their antibacterial activity against four microbial pathogens (Staphylococcus aureus, Enterococcus faecalis, Pseudomonas aeruginosa and Escherichia coli), and compounds 1, 2, 3 and 5 displayed significant selective antibacterial activity against S. aureus with MIC values ranging from 3.9 to 7.8 µg/mL.

15.
J Cancer Res Ther ; 18(5): 1231-1240, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36204867

RESUMO

The totally implantable venous access device (TIVAD) has been widely used in clinical nursing work in China. The use of TIVAD has significantly improved the safety of venous access and reduced the pain caused by a repeated puncture; however, it may also bring with it varying degrees of complications associated with the long-term insertion of TIVAD and the maintenance quality of the venous access. Standard maintenance of the venous access for TIVAD is very important for reducing complications and improving the efficacy and patient's quality of life. This consensus briefly describes the fundamental knowledge and operating procedures of TIVAD while focusing on the evaluation and management of perioperative nursing, the observation and treatment of complications, the operation methods, and precautions for maintenance of venous access, as well as health education. This agreement seeks to standardize the nursing care of TIVAD patients in China.


Assuntos
Cateterismo Venoso Central , Cateteres de Demora , Consenso , Humanos , Próteses e Implantes , Qualidade de Vida
16.
BMC Neurosci ; 12: 70, 2011 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-21767388

RESUMO

BACKGROUND: In cat visual cortex, critical period neuronal plasticity is minimal until approximately 3 postnatal weeks, peaks at 5 weeks, gradually declines to low levels at 20 weeks, and disappears by 1 year of age. Dark rearing slows the entire time course of this critical period, such that at 5 weeks of age, normal cats are more plastic than dark reared cats, whereas at 20 weeks, dark reared cats are more plastic. Thus, a stringent criterion for identifying genes that are important for plasticity in visual cortex is that they show differences in expression between normal and dark reared that are of opposite direction in young versus older animals. RESULTS: The present study reports the identification by differential display PCR of a novel gene, α-chimaerin, as a candidate visual cortex critical period plasticity gene that showed bidirectional regulation of expression due to age and dark rearing. Northern blotting confirmed the bidirectional expression and 5'RACE sequencing identified the gene. There are two alternatively-spliced α-chimaerin isoforms: α1 and α2. Western blotting extended the evidence for bidirectional regulation of visual cortex α-chimaerin isoform expression to protein in cats and mice. α1- and α2-Chimaerin were elevated in dark reared compared to normal visual cortex at the peak of the normal critical period and in normal compared to dark reared visual cortex at the nadir of the normal critical period. Analysis of variance showed a significant interaction in both cats and mice for both α-chimaerin isoforms, indicating that the effect of dark rearing depended on age. This differential expression was not found in frontal cortex. CONCLUSIONS: Chimaerins are RhoGTPase-activating proteins that are EphA4 effectors and have been implicated in a number of processes including growth cone collapse, axon guidance, dendritic spine development and the formation of corticospinal motor circuits. The present results identify α-chimaerin as a candidate molecule for a role in the postnatal critical period of visual cortical plasticity.


Assuntos
Envelhecimento/fisiologia , Quimerina 1/metabolismo , Período Crítico Psicológico , Plasticidade Neuronal/genética , Córtex Visual/fisiologia , Animais , Gatos , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Camundongos , Especificidade da Espécie
17.
Transl Pediatr ; 10(10): 2409-2417, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34765464

RESUMO

BACKGROUND: The present study aimed to investigate the P-wave changes in intracavitary electrocardiography (IC-ECG) during catheterization with a peripherally inserted central catheter (PICC) in order to provide guidance for the accurate localization of the tip of the PICC. METHODS: A total of 106 newborns who needed a PICC were randomly divided into two groups-a study group and a control group-using a random number table, with 53 cases in each group. In the study group, the ECG monitor was connected after the successful puncture and insertion of the PICC into the right sternoclavicular joint, and the position of the catheter tip was determined according to the P-wave changes on the IC-ECG. Localization X-rays were taken at the same time. In the control group, after the successful routine puncture and insertion of the PICC into the location to a predetermined length, localization X-rays were taken. The accuracy, procedure duration, and cost of the two localization methods were evaluated. RESULTS: The accuracy of the localization in the study group was 92.5%, but the difference was not significant when compared with the control group (P>0.05). The duration of the procedure in the study group was 5.12±1.57 minutes, and the cost was 7.12±0.56 yuan, both of which were significantly different when compared with the control group (P<0.05). CONCLUSIONS: P-wave changes during IC-ECG have high accuracy in determining the location of the tip of the PICC. It is also a simple method and has certain clinical application value. TRIAL REGISTRATION: Chinese Clinical Trial Registry (number: ChiCTR2100047660).

18.
Korean J Orthod ; 50(2): 145-154, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32257940

RESUMO

Moving the mandibular posterior teeth into a severely atrophic edentulous space is a challenge. A carefully designed force-and-moment system that results in bodily protraction of the posterior teeth with balanced bone resorption and apposition is needed in such cases. This report describes the treatment of a 19-year-old woman with missing mandibular first molars due to juvenile periodontitis. Miniscrews were used as absolute anchorage during protraction of the mandibular second and third molars. Bodily mesial movement of the mandibular second and third molars was achieved over a distance of 11 to 17 mm after 39 months of orthodontic treatment.

19.
Toxicol Appl Pharmacol ; 236(2): 194-201, 2009 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-19371603

RESUMO

Acrolein is a ubiquitous component of environmental pollutants such as automobile exhaust, cigarette, wood, and coal smoke. It is also a natural constituent of several foods and is generated endogenously during inflammation or oxidation of unsaturated lipids. Because increased inflammation and episodic exposure to acrolein-rich pollutants such as traffic emissions or cigarette smoke have been linked to acute myocardial infarction, we examined the effects of acrolein on matrix metalloproteinases (MMPs), which destabilize atherosclerotic plaques. Our studies show that exposure to acrolein resulted in the secretion of MMP-9 from differentiated THP-1 macrophages. Acrolein-treatment of macrophages also led to an increase in reactive oxygen species (ROS), free intracellular calcium ([Ca2+](i)), and xanthine oxidase (XO) activity. ROS production was prevented by allopurinol, but not by rotenone or apocynin and by buffering changes in [Ca2+](I) with BAPTA-AM. The increase in MMP production was abolished by pre-treatment with the antioxidants Tiron and N-acetyl cysteine (NAC) or with the xanthine oxidase inhibitors allopurinol or oxypurinol. Finally, MMP activity was significantly stimulated in aortic sections from apoE-null mice containing advanced atherosclerotic lesions after exposure to acrolein ex vivo. These observations suggest that acrolein exposure results in MMP secretion from macrophages via a mechanism that involves an increase in [Ca2+](I), leading to xanthine oxidase activation and an increase in ROS production. ROS-dependent activation of MMPs by acrolein could destabilize atherosclerotic lesions during brief episodes of inflammation or pollutant exposure.


Assuntos
Acroleína/toxicidade , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Metaloproteinases da Matriz/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Animais , Apolipoproteínas E/genética , Apolipoproteínas E/metabolismo , Aterosclerose/enzimologia , Aterosclerose/genética , Cálcio/metabolismo , Linhagem Celular , Poluentes Ambientais/toxicidade , Regulação da Expressão Gênica/efeitos dos fármacos , Camundongos , Camundongos Knockout , Xantina Oxidase/metabolismo
20.
Redox Biol ; 24: 101177, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30939431

RESUMO

Previous studies indicate that mitochondria-localized lactate dehydrogenase (mLDH) might be a significant contributor to metabolism. In the heart, the presence of mLDH could provide cardiac mitochondria with a higher capacity to generate reducing equivalents directly available for respiration, especially during exercise when circulating lactate levels are high. The purpose of this study was to test the hypothesis that mLDH contributes to striated muscle bioenergetic function. Mitochondria isolated from murine cardiac and skeletal muscle lacked an appreciable ability to respire on lactate in the absence or presence of exogenous NAD+. Although three weeks of treadmill running promoted physiologic cardiac growth, mitochondria isolated from the hearts of acutely exercised or exercise-adapted mice showed no further increase in lactate oxidation capacity. In all conditions tested, cardiac mitochondria respired at >20-fold higher levels with provision of pyruvate compared with lactate. Similarly, skeletal muscle mitochondria showed little capacity to respire on lactate. Protease protection assays of isolated cardiac mitochondria confirmed that LDH is not localized within the mitochondrion. We conclude that mLDH does not contribute to cardiac bioenergetics in mice.


Assuntos
L-Lactato Desidrogenase/metabolismo , Mitocôndrias Musculares/metabolismo , Músculo Estriado/metabolismo , Animais , Respiração Celular , Masculino , Camundongos , Mitocôndrias Cardíacas/metabolismo , Oxirredução , Condicionamento Físico Animal
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