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1.
Proteomics ; 22(13-14): e2200018, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35633524

RESUMO

IPF is a progressive fibrotic lung disease whose pathogenesis remains incompletely understood. We have previously discovered pathologic mesenchymal progenitor cells (MPCs) in the lungs of IPF patients. IPF MPCs display a distinct transcriptome and create sustained interstitial fibrosis in immune deficient mice. However, the precise pathologic alterations responsible for this fibrotic phenotype remain to be uncovered. Quantitative mass spectrometry and interactomics is a powerful tool that can define protein alterations in specific subcellular compartments that can be implemented to understand disease pathogenesis. We employed quantitative mass spectrometry and interactomics to define protein alterations in the nuclear compartment of IPF MPCs compared to control MPCs. We identified increased nuclear levels of PARP1, CDK1, and BACH1. Interactomics implicated PARP1, CDK1, and BACH1 as key hub proteins in the DNA damage/repair, differentiation, and apoptosis signaling pathways respectively. Loss of function and inhibitor studies demonstrated important roles for PARP1 in DNA damage/repair, CDK1 in regulating IPF MPC stemness and self-renewal, and BACH1 in regulating IPF MPC viability. Our quantitative mass spectrometry studies combined with interactomic analysis uncovered key roles for nuclear PARP1, CDK1, and BACH1 in regulating IPF MPC fibrogenicity.


Assuntos
Fibrose Pulmonar Idiopática , Células-Tronco Mesenquimais , Animais , Fibrose Pulmonar Idiopática/genética , Fibrose Pulmonar Idiopática/metabolismo , Fibrose Pulmonar Idiopática/patologia , Pulmão/metabolismo , Células-Tronco Mesenquimais/metabolismo , Camundongos , Proteína Nodal/genética , Proteína Nodal/metabolismo , Fenótipo , Proteoma/metabolismo , Proteômica
2.
Talanta ; 276: 126197, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38728800

RESUMO

Whereas the close associations of cesium ion with organochlorine compounds have been previously documented, the present report is the first attempt to exploit these interactions to create a trichloroethylene (TCE)-selective sensor. Gold monolayer-protected clusters peripherally functionalized with Cs+ ions were used to prepare a chemiresistance film on MEMS-fabricated interdigitated electrodes. Vapor sensing properties of the cesium-rich chemiresistor were determined using a panel of chlorinated hydrocarbons including TCE as well as polar and non-polar VOCs for comparison. The sensor was selective and highly sensitive toward VOCs containing a 1,2-dichloro group at concentrations as low as 0.1 ppm. The results suggest the key interaction contributing to sensor response is a bidentate, metallocycle-like coordination of the 1,2-dichloro group to the cesium cations at the sensor surface.

3.
Cell Rep ; 43(4): 114049, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38573853

RESUMO

Heterotopic ossification (HO) is a challenging condition that occurs after musculoskeletal injury and is characterized by the formation of bone in non-skeletal tissues. While the effect of HO on blood vessels is well established, little is known about its impact on lymphatic vessels. Here, we use a mouse model of traumatic HO to investigate the relationship between HO and lymphatic vessels. We show that injury triggers lymphangiogenesis at the injury site, which is associated with elevated vascular endothelial growth factor C (VEGF-C) levels. Through single-cell transcriptomic analyses, we identify mesenchymal progenitor cells and tenocytes as sources of Vegfc. We demonstrate by lineage tracing that Vegfc-expressing cells undergo osteochondral differentiation and contribute to the formation of HO. Last, we show that Vegfc haploinsufficiency results in a nearly 50% reduction in lymphangiogenesis and HO formation. These findings shed light on the complex mechanisms underlying HO formation and its impact on lymphatic vessels.


Assuntos
Linfangiogênese , Células-Tronco Mesenquimais , Ossificação Heterotópica , Fator C de Crescimento do Endotélio Vascular , Animais , Ossificação Heterotópica/metabolismo , Ossificação Heterotópica/patologia , Ossificação Heterotópica/genética , Fator C de Crescimento do Endotélio Vascular/metabolismo , Fator C de Crescimento do Endotélio Vascular/genética , Camundongos , Células-Tronco Mesenquimais/metabolismo , Vasos Linfáticos/metabolismo , Vasos Linfáticos/patologia , Diferenciação Celular , Tenócitos/metabolismo , Osteogênese , Haploinsuficiência , Camundongos Endogâmicos C57BL , Modelos Animais de Doenças , Masculino
4.
Stem Cell Res Ther ; 15(1): 58, 2024 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-38433223

RESUMO

OBJECTIVES: Currently, no approved stem cell-based therapies for preserving ovarian function during aging. To solve this problem, we developed a long-term treatment for human embryonic stem cell-derived mesenchymal progenitor cells (hESC-MPCs). We investigated whether the cells retained their ability to resist ovarian aging, which leads to delayed reproductive senescence. MATERIALS AND METHODS: In a middle-aged female model undergoing natural aging, we analyzed whether hESC-MPCs benefit the long-term maintenance of reproductive fecundity and ovarian reservoirs and how their transplantation regulates ovarian function. RESULTS: The number of primordial follicles and mice with regular estrous cycles were increased in perimenopausal mice who underwent multiple introductions of hESC-MPCs compared to age-matched controls. The estradiol levels in the hESC-MPCs group were restored to those in the young and adult groups. Embryonic development and live birth rates were higher in the hESC-MPC group than in the control group, suggesting that hESC-MPCs delayed ovarian senescence. In addition to their direct effects on the ovary, multiple-treatments with hESC-MPCs reduced ovarian fibrosis by downregulating inflammation and fibrosis-related genes via the suppression of myeloid-derived suppressor cells (MDSCs) produced in the bone marrow. CONCLUSIONS: Multiple introductions of hESC-MPCs could be a useful approach to prevent female reproductive senescence and that these cells are promising sources for cell therapy to postpone the ovarian aging and retain fecundity in perimenopausal women.


Assuntos
Células-Tronco Embrionárias Humanas , Células-Tronco Mesenquimais , Adulto , Gravidez , Pessoa de Meia-Idade , Feminino , Humanos , Animais , Camundongos , Perimenopausa , Fertilidade , Envelhecimento , Fibrose
5.
Front Oncol ; 13: 1251492, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38260838

RESUMO

This report describes a rare case of double primary cancer in a female patient aged 49 years who died 2 years after diagnosis. The patient was diagnosed with BRAFV600E-mutant metastatic papillary thyroid carcinoma (PTC) and ALK fusion-positive metastatic lung adenocarcinoma. She presented with multifocal thyroid lesions and underwent radical thyroidectomy and bilateral cervical lymphadenectomy. Thyroid ultrasound revealed the presence of five hypoechoic nodules with irregular margins and microcalcifications; an irregular inhomogeneous hypoechoic level IV cervical lymph node was also found on the right side. Histological analysis confirmed the presence of metastatic PTC, and the tumor tested positive for the BRAFV600E mutation. Ultrasound of the neck, which was performed 4 months postdischarge, revealed enlargement of the left-sided cervical lymph nodes; a biopsy from these nodes confirmed a diagnosis of metastatic PTC. Positron emission tomography-computed tomography scans revealed the presence of multiple pulmonary hypermetabolic foci scattered across bilateral lung fields. Multiple hypermetabolic foci were also observed in the lymph nodes on both sides of the neck, axillae, and mediastinum; in addition, there was evidence of bone destruction with hypermetabolic foci. Supplementary reports from the histological and immunohistochemical analyses of cervical lymph node tissue obtained during primary surgery confirmed the presence of metastatic PTC and poorly differentiated lung adenocarcinoma. In particular, one enlarged cervical lymph node located on the right side of the neck demonstrated tumor components of both PTC and lung adenocarcinoma. Pathological analysis of axillary lymph node puncture biopsy confirmed the presence of metastatic lung adenocarcinoma, and gene analysis revealed the presence of ALK fusion. The patient received targeted therapy based on a multidisciplinary discussion. However, she had a poor prognosis and died 2 years after the diagnosis. The initial thyroid ultrasound findings were reviewed retrospectively; the findings suggested that the possibility of double primary cancers should be considered in cases where the enlarged cervical lymph nodes are highly suspicious of PTC and present as inhomogeneous hypoechoic masses with irregular morphology.

6.
J Dent Sci ; 17(2): 848-855, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35756757

RESUMO

Abstract Background/purpose: Self-adhesive resins (SARs) do not require additional restorative adhesives and provide adequate adhesion to mineralized dental structures by shortening the bonding time in clinics where moisture control and isolation are difficult. The aim of this study was to evaluate the mechanical and biological properties of SARs containing mesoporous bioactive glass nanoparticles (MBNs) and 2-methacryloyloxyethyl phosphorylcholine (MPC) and to determine their antibacterial and remineralization effects. Materials and methods: MBNs and MPC were added to SARs to improve their physical properties and remineralization ability. The experimental resins assessed in this study were SARs mixed with 3%MPC, 5%MPC, 1%MBN+3%MPC, or 3%MBN+3%MPC. The shear bond strength, microhardness, adhesive remnant index, ion dissolution, degree of conversion, and antibacterial properties of the SARs were evaluated. To assess the remineralization properties, micro-computed tomography analysis was performed after pH cycling. Results: Increasing the MBN content in SAR resulted in higher microhardness compared to the control SAR. The shear bond strength decreased in the SAR+5%MPC group and increased in the SAR+1%MBN+3%MPC and SAR+3%MBN+5%MPC groups. Conclusion: Our findings suggest that SARs containing MBNs and MPC have antibacterial and remineralization effects on the enamel.

7.
Ann Transl Med ; 10(6): 360, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35434026

RESUMO

Background: Retroperitoneal liposarcoma (RPLS) is a rare, biologically heterogeneous tumor with distinct clinical characteristics, such as frequent local recurrence, repeated relapse, and rare distant metastasis. No effective targeted therapy is available for RPLS. Here, we aim to determine the pathological functions and therapeutic potential of carbohydrate sulfotransferase 15 (CHST15) in RPLS. Methods: Tumor-derived mesenchymal progenitor cells (MPCs) and normal adipose derived mesenchymal stem cells (MSCs) were obtained from patients with RPLS. MPCs and MSCs were isolated and characterized based on surface markers, proliferation, and differentiation using flow cytometry and molecular staining. Transcriptome analysis was performed to decipher expression profile of differentiation-related genes in 3 paired MSCs and MPCs. Further confirmation of genes were performed using quantitative real-time polymerase chain reaction (qRT-PCR). Plasmids overexpressing CHST15 were transfected into adipose MSCs to examine fibrosis-related gene expression at mRNA level by real-time PCR. Results: The tumor stromal-derived MPCs expressed CD105, CD73, and CD90, and exhibited osteogenic and adipogenic differentiation potential in vitro. The proliferation of tumor-derived MPCs was significantly lower than that of normal adipose-derived MSCs (P<0.001). Transcriptome analysis revealed upregulation of IL-7R, ALPL, PKNOX2, and CHST15 in tumor-derived MPCs. CHST15 was highly expressed in tumor-derived MPCs (P<0.001). CHST15 mediated fibrosis-related FGF2 gene expression in MSCs (P<0.05) and MPCs (P<0.001). Conclusions: CHST15 is upregulated in tumor-derived MPCs and regulates fibrosis in RPLS. This provides clues for development of novel therapeutic strategies by targeting CHST15-induced MPC activation in RPLS.

8.
Front Cell Dev Biol ; 9: 669381, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34291045

RESUMO

Mesangiogenic progenitor cells (MPCs) have been isolated from human bone marrow (BM) mononuclear cells. They attracted particular attention for the ability to differentiate into exponentially growing mesenchymal stromal cells while retaining endothelial differentiative potential. MPC power to couple mesengenesis and angiogenesis highlights their tissue regenerative potential and clinical value, with particular reference to musculoskeletal tissues regeneration. BM and adipose tissue represent the most promising adult multipotent cell sources for bone and cartilage repair, although discussion is still open on their respective profitability. Culture determinants, as well as tissues of origin, appeared to strongly affect the regenerative potential of cell preparations, making reliable methods for cell isolation and growth a prerequisite to obtain cell-based medicinal products. Our group had established a definite consistent protocol for MPC culture, and here, we present data showing MPCs to be tissue specific.

9.
Am J Sports Med ; 49(4): 1073-1085, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33719605

RESUMO

BACKGROUND: Skeletal muscle injuries represent a major concern in sports medicine. Cell therapy has emerged as a promising therapeutic strategy for muscle injuries, although the preclinical data are still inconclusive and the potential clinical use of cell therapy has not yet been established. PURPOSE: To evaluate the effects of muscle precursor cells (MPCs) on muscle healing in a small animal model. STUDY DESIGN: Controlled laboratory study. METHODS: A total of 27 rats were used in the study. MPCs were isolated from rat (n = 3) medial gastrocnemius muscles and expanded in primary culture. Skeletal muscle injury was induced in 24 rats, and the animals were assigned to 3 groups. At 36 hours after injury, animals received treatment based on a single ultrasound-guided MPC (105 cells) injection (Cells group) or MPC injection in combination with 2 weeks of daily exercise training (Cells+Exercise group). Animals receiving intramuscular vehicle injection were used as controls (Vehicle group). Muscle force was determined 2 weeks after muscle injury, and muscles were collected for histological and immunofluorescence evaluation. RESULTS: Red fluorescence-labeled MPCs were successfully transplanted in the site of the injury by ultrasound-guided injection and were localized in the injured area after 2 weeks. Transplanted MPCs participated in the formation of regenerating muscle fibers as corroborated by the co-localization of red fluorescence with developmental myosin heavy chain (dMHC)-positive myofibers by immunofluorescence analysis. A strong beneficial effect on muscle force recovery was detected in the Cells and Cells+Exercise groups (102.6% ± 4.0% and 101.5% ± 8.5% of maximum tetanus force of the injured vs healthy contralateral muscle, respectively) compared with the Vehicle group (78.2% ± 5.1%). Both Cells and Cells+Exercise treatments stimulated the growth of newly formed regenerating muscles fibers, as determined by the increase in myofiber cross-sectional area (612.3 ± 21.4 µm2 and 686.0 ± 11.6 µm2, respectively) compared with the Vehicle group (247.5 ± 10.7 µm2), which was accompanied by a significant reduction of intramuscular fibrosis in Cells and Cells+Exercise treated animals (24.2% ± 1.3% and 26.0% ± 1.9% of collagen type I deposition, respectively) with respect to control animals (40.9% ± 4.1% in the Vehicle group). MPC treatment induced a robust acceleration of the muscle healing process as demonstrated by the decreased number of dMHC-positive regenerating myofibers (enhanced replacement of developmental myosin isoform by mature myosin isoforms) (4.3% ± 2.6% and 4.1% ± 1.5% in the Cells and Cells+Exercise groups, respectively) compared with the Vehicle group (14.8% ± 13.9%). CONCLUSION: Single intramuscular administration of MPCs improved histological outcome and force recovery of the injured skeletal muscle in a rat injury model that imitates sports-related muscle injuries. Cell therapy showed a synergistic effect when combined with an early active rehabilitation protocol in rats, which suggests that a combination of treatments can generate novel therapeutic strategies for the treatment of human skeletal muscle injuries. CLINICAL RELEVANCE: Our study demonstrates the strong beneficial effect of MPC transplant and the synergistic effect when the cell therapy is combined with an early active rehabilitation protocol for muscle recovery in rats; this finding opens new avenues for the development of effective therapeutic strategies for muscle healing and clinical trials in athletes undergoing MPC transplant and rehabilitation protocols.


Assuntos
Doenças Musculares , Medicina Esportiva , Animais , Músculo Esquelético , Ratos , Recuperação de Função Fisiológica , Regeneração
10.
Transl Cancer Res ; 9(3): 2053-2059, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35117554

RESUMO

Due to the favorable prognosis of gastric cancer (GC), the incidence of second primary cancer (SPC) accompanied with GC has increased. Here, we reported a case of a 69-year-old male patient with metachronous GC and colon cancer, who had undergone laparoscopic radical resection of distal GC 4 years ago. During this hospitalization, the patient underwent laparoscopic radical resection of left hemicolectomy for metachronous colon cancer. Few literatures have reported that patients with metachronous GC and colon cancer can receive laparoscopic surgery successfully. The patient recovered well and was discharged on day 10 post-operation. The pathologic specimen was identified as metachronous colon cancer. We concluded that GC patients need regular standard follow-up programs after undergoing operations. For multiple primary cancers (MPCs), treatments need to be individualized and comprehensive. Laparoscopic surgery is recommended as an appropriate option.

11.
Nanomaterials (Basel) ; 9(9)2019 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-31514483

RESUMO

Gold clusters protected by 3-MBA ligands (MBA = mercaptobenzoic acid, -SPhCO2H) have attracted recent interest due to their unusual structures and their advantageous ligand-exchange and bioconjugation properties. Azubel et al. first determined the core structure of an Au68-complex, which was estimated to have 32 ligands (3-MBA groups). To explain the exceptional structure-composition and reaction properties of this complex, and its larger homologs, Tero et al. proposed a "dynamic stabilization" via carboxyl O-H--Au interactions. Herein, we report the first results of an integrated liquid chromatography/mass spectrometer (LC/MS) analysis of unfractionated samples of gold/3-MBA clusters, spanning a narrow size range 13.4 to 18.1 kDa. Using high-throughput procedures adapted from bio-macromolecule analyses, we show that integrated capillary high performance liquid chromatography electrospray ionization mass spectrometer (HPLC-ESI-MS), based on aqueous-methanol mobile phases and ion-pairing reverse-phase chromatography, can separate several major components from the nanoclusters mixture that may be difficult to resolve by standard native gel electrophoresis due to their similar size and charge. For each component, one obtains a well-resolved mass spectrum, nearly free of adducts or signs of fragmentation. A consistent set of molecular mass determinations is calculated from detected charge-states tunable from 3- (or lower), to 2+ (or higher). One thus arrives at a series of new compositions (n, p) specific to the Au/3-MBA system. The smallest major component is assigned to the previously unknown (48, 26); the largest one is evidently (67, 30), vs. the anticipated (68, 32). Various explanations for this discrepancy are considered. A prospective is given for the various members of this novel series, along with a summary of the advantages and present limitations of the micro-scale integrated LC/MS approach in characterizing such metallic-core macro-molecules, and their derivatives.

12.
FEBS J ; 284(3): 451-465, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27987376

RESUMO

Pioglitazone is used globally for the treatment of type 2 diabetes mellitus (T2DM) and is one of the most effective therapies for improving glucose homeostasis and insulin resistance in T2DM patients. However, its mechanism of action in the tissues and pathways that regulate glucose metabolism are incompletely defined. Here we investigated the direct effects of pioglitazone on hepatocellular pyruvate metabolism and the dependency of these observations on the purported regulators of mitochondrial pyruvate transport, MPC1 and MPC2. In cultured H4IIE hepatocytes, pioglitazone inhibited [2-14 C]-pyruvate oxidation and pyruvate-driven oxygen consumption and, in mitochondria isolated from both hepatocytes and human skeletal muscle, pioglitazone selectively and dose-dependently inhibited pyruvate-driven ATP synthesis. Pioglitazone also suppressed hepatocellular glucose production (HGP), without influencing the mRNA expression of key HGP regulatory genes. Targeted siRNA silencing of MPC1 and 2 caused a modest inhibition of pyruvate oxidation and pyruvate-driven ATP synthesis, but did not alter pyruvate-driven HGP and, importantly, it did not influence the actions of pioglitazone on either pathway. In summary, these findings outline a novel mode of action of pioglitazone relevant to the pathogenesis of T2DM and suggest that targeting pyruvate metabolism may lead to the development of effective new T2DM therapies.


Assuntos
Trifosfato de Adenosina/antagonistas & inibidores , Glucose/antagonistas & inibidores , Hepatócitos/efeitos dos fármacos , Hipoglicemiantes/farmacologia , Mitocôndrias/efeitos dos fármacos , Tiazolidinedionas/farmacologia , Trifosfato de Adenosina/biossíntese , Animais , Proteínas de Transporte de Ânions/antagonistas & inibidores , Proteínas de Transporte de Ânions/genética , Proteínas de Transporte de Ânions/metabolismo , Transporte Biológico/efeitos dos fármacos , Radioisótopos de Carbono , Linhagem Celular , Gluconeogênese/efeitos dos fármacos , Glucose/biossíntese , Glicólise/efeitos dos fármacos , Hepatócitos/citologia , Hepatócitos/metabolismo , Mitocôndrias/metabolismo , Proteínas de Transporte da Membrana Mitocondrial/antagonistas & inibidores , Proteínas de Transporte da Membrana Mitocondrial/genética , Proteínas de Transporte da Membrana Mitocondrial/metabolismo , Oxirredução , Fosforilação Oxidativa/efeitos dos fármacos , Pioglitazona , Ácido Pirúvico/metabolismo , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Ratos
13.
Nanomaterials (Basel) ; 5(3): 1211-1222, 2015 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-28347061

RESUMO

High affinity thiolate-based polymeric capping ligands are known to impart stability onto nanosized gold nanoparticles. Due to the stable gold-sulfur bond, the ligand forms a protective layer around the gold core and subsequently controls the physicochemical properties of the resultant nanogold mononuclear protected clusters (AuMPCs). The choice of ligands to use as surfactants for AuMPCs largely depends on the desired degree of hydrophilicity and biocompatibility of the MPCs, normally dictated by the intended application. Subsequent surface modification of AuMPCs allows further conjugation of additional biomolecules yielding bilayer or multilayered clusters suitable for bioanalytical applications ranging from targeted drug delivery to diagnostics. In this study, we discuss our recent laboratory findings on a simple route for the introduction of Trans-Activator of Transcription (TAT) peptide onto the surface of biotin-derivatised gold MPCs via the biotin-strepavidin interaction. By changing the surface loading of biotin, controlled amounts of TAT could be attached. This bioconjugate system is very attractive as a carrier in intercellular delivery of various delivery cargoes such as antibodies, proteins and oligonucleotides.

14.
ACS Nano ; 9(8): 8344-51, 2015 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-26168937

RESUMO

Rich and tunable physicochemical properties make noble metal clusters promising candidates as novel nanomolecules for a variety of applications. Spectroelectrochemistry analysis is employed to resolve previously inaccessible electronic transitions in Au130 clusters stabilized by a monolayer of di- and monothiolate ligands. Well-defined quantized double-layer charging of the Au core and oxidizable ligands make this Au130 nanocluster unique among others and enable selective electrolysis to different core and ligand charge states. Subsequent analysis of the corresponding absorption changes reveals that different absorption bands originate from different electronic transitions involving both metal core energy states and ligand molecular orbitals. Besides the four discrete absorption bands in the steady-state UV-visible-near-IR absorption spectrum, additional transitions otherwise not detectable are resolved upon selective addition/removal of electrons at cores and ligand energy states, respectively, upon electrolysis. An energy diagram is proposed that successfully explains the major features observed in electrochemistry and absorption spectroscopy. Those assignments are believed applicable and effective to explain similar transitions observed in some other Au thiolate clusters.

15.
J Hazard Mater ; 266: 34-41, 2014 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-24374563

RESUMO

Maintaining coherence among environmental quality objectives (EQOs) should be an important consideration for the EQOs to be met simultaneously. The objectives of the present work were to demonstrate the need of accurate variability prediction by models and to present considerations in selecting models for testing coherence of the EQOs. SimpleBox and POPsME were chosen as the two different types of models to compare the prediction variability and its influence on the results of coherence test among the maximum permissible concentrations (MPCs) of polycyclic aromatic hydrocarbons (PAHs) in South Korea. False calls by these models on coherence were found to occur often due to inaccurate prediction of variability in the concentration ratio at steady state, strongly suggesting that models for coherence test should be accurate in predicting not only the point value representing the concentration ratio but the variability of the value. It was demonstrated that spatially resolved dynamic models would have an intrinsic advantage over one box steady state models in reducing the rate of false negative call.


Assuntos
Poluentes Ambientais/análise , Modelos Teóricos , Hidrocarbonetos Policíclicos Aromáticos/análise , Monitoramento Ambiental , República da Coreia
16.
Free Radic Biol Med ; 65: 317-323, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23851030

RESUMO

The ability of muscles to regenerate successfully following damage diminishes with age and this appears to be a major contributor to the development of muscle weakness and physical frailty. Successful muscle regeneration is dependent on appropriate reinnervation of regenerating muscle. Age-related changes in the interactions between nerve and muscle are poorly understood but may play a major role in the defective regeneration. During aging there is defective redox homeostasis and an accumulation of oxidative damage in nerve and muscle that may contribute to defective regeneration. The aim of this review is to summarise the evidence that abnormal reactive oxygen species (ROS) generation in nerve and/or muscle may be responsible for the defective regeneration that contributes to the degeneration of skeletal muscle observed during aging. Identifying the importance of ROS generation in skeletal muscle during aging could have fundamental implications for interventions to prevent muscle degeneration and treatments to reverse the age-related decline in muscle mass and function.


Assuntos
Envelhecimento/patologia , Envelhecimento/fisiologia , Músculo Esquelético/fisiologia , Espécies Reativas de Oxigênio/efeitos adversos , Humanos , Regeneração
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