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1.
J Orthop ; 52: 67-73, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38435314

RESUMO

Introduction: The aim of the research was to conduct a systematic review of dose-response meta-analysis, examining the correlation between the energy of extracorporeal shockwave therapy (ESWT) and clinical outcomes for patients with knee osteoarthritis (OA). Methods: We conducted a systematic review of three online databases - PubMed, Embase, and Cochrane Library - to collect relevant articles from their inception to May 2023. We included the articles that investigated the efficacy of ESWT in treating knee OA and were designed using randomized controlled trials (RCTs). The main outcomes were measured using the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) for primary outcomes and the Visual Analog Scale (VAS) for secondary outcomes. We conducted a dose-response meta-analysis to examine the correlation between the energy of ESWT and clinical outcomes. Results: Our study included a total of 7 RCTs (comprising 450 subjects) that met the inclusion criteria. We found a negative linear relationship between the doses of ESWT and WOMAC scores at the 1-week (p = 0.0398) and 4-week (p = 0.001) follow-up periods, but not at the 12-week follow-up period (p = 0.202). Furthermore, at the 4-week (p = 0.0477) and 12-week (p < 0.001) follow-up periods, a negative linear connection was found between the ESWT dose and VAS scores, but not at the 1-week follow-up period (p = 0.2268). Conclusions: Our results demonstrate a dose-response connection between the energy of ESWT and clinical outcomes. This suggests that using higher energy levels of ESWT to treat knee OA could lead to greater improvement in clinical outcomes compared to using lower energy levels.

2.
Chembiochem ; 25(3): e202300744, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38055188

RESUMO

Hirudins, natural sulfo(glyco)proteins, are clinical anticoagulants that directly inhibit thrombin, a key coagulation factor. Their potent thrombin inhibition primarily results from antagonistic interactions with both the catalytic and non-catalytic sites of thrombin. Hirudins often feature sulfate moieties on Tyr residues in their anionic C-terminus region, enabling strong interactions with thrombin exosite-I and effectively blocking its engagement with fibrinogen. Although sulfotyrosines have been identified in various hirudin variants, the precise relationship between sulfotyrosine and the number of negatively charged amino acids within the anionic-rich C-terminus peptide domain for the binding of thrombin has remained elusive. By using Fmoc-SPPS, hirudin dodecapeptides homologous to the C-terminus of hirudin variants from various leech species were successfully synthesized, and the effect of sulfotyrosine and the number of negatively charged amino acids on hirudin-thrombin interactions was investigated. Our findings did not reveal any synergistic effect between an increasing number of sulfotyrosines or negatively charged amino acids and their inhibitory activity on thrombin or fibrinolysis in the assays, despite a higher binding level toward thrombin in the sulfated dodecapeptide Hnip_Hirudin was observed in SPR analysis.


Assuntos
Hirudinas , Trombina , Tirosina/análogos & derivados , Hirudinas/farmacologia , Hirudinas/química , Hirudinas/metabolismo , Aminoácidos , Peptídeos/farmacologia , Sítios de Ligação
3.
J Clin Med ; 12(17)2023 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-37685720

RESUMO

Patients with hematologic malignancies are reported to have a more severe course of coronavirus disease 2019 (COVID-19) and be less responsive to vaccination. In this prospective study, we aimed to evaluate the serological responses to booster COVID-19 vaccines of Taiwanese patients with hematologic malignancies and identify potential predictive markers for effective neutralizing immunity. This study enrolled 68 patients with hematologic malignancies and 68 age- and gender-matched healthy control subjects who received three doses of vaccination against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) from 1 January 2022 to 31 October 2022. The SARS-CoV-2 immunoglobulin G (IgG) spike antibody level was measured with the Abbott assay. The effective neutralization capacity was defined as an anti-spike IgG level of ≥4160 AU/mL. Among the 68 patients with hematologic malignancies, 89.7% achieved seroconversion after booster doses. Seven patients with actively treated lymphoma remained seronegative and had the lowest humoral responses among patients with different types of hematologic malignancies. Despite comparable antibody titers between patients and healthy individuals, rates of effective neutralization (66.2% vs. 86.8%, respectively; p = 0.005) were significantly reduced in patients with hematologic malignancies. In a multivariate analysis, the independent predictors for effective neutralization were a lack of B-cell-targeted agents within six months of vaccination (odds ratio, 15.2; 95% confidence interval, 2.7-84.2; p = 0.002) and higher immunoglobulin levels (odds ratio, 4.4; 95% confidence interval, 1.3-14.7; p = 0.017). In conclusion, the majority of patients with hematologic malignancies achieved seroconversion after booster vaccination. Patients with ongoing B-cell depletion and hypogammaglobinemia were identified as having negative predictive markers for effective neutralization.

4.
ACS Appl Mater Interfaces ; 15(27): 32967-32983, 2023 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-37384742

RESUMO

Due to the mortality associated with thrombosis and its high recurrence rate, there is a need to investigate antithrombotic approaches. Noninvasive site-specific thrombolysis is a current approach being used; however, its usage is characterized by the following limitations: low targeting efficiency, poor ability to penetrate clots, rapid half-life, lack of vascular restoration mechanisms, and risk of thrombus recurrence that is comparable to that of traditional pharmacological thrombolysis agents. Therefore, it is vital to develop an alternative technique that can overcome the aforementioned limitations. To this end, a cotton-ball-shaped platelet (PLT)-mimetic self-assembly framework engineered with a phototherapeutic poly(3,4-ethylenedioxythiophene) (PEDOT) platform has been developed. This platform is capable of delivering a synthetic peptide derived from hirudin P6 (P6) to thrombus lesions, forming P6@PEDOT@PLT nanomotors for noninvasive site-specific thrombolysis, effective anticoagulation, and vascular restoration. Regulated by P-selectin mediation, the P6@PEDOT@PLT nanomotors target the thrombus site and subsequently rupture under near-infrared (NIR) irradiation, achieving desirable sequential drug delivery. Furthermore, the movement ability of the P6@PEDOT@PLT nanomotors under NIR irradiation enables effective penetration deep into thrombus lesions, enhancing bioavailability. Biodistribution analyses have shown that the administered P6@PEDOT@PLT nanomotors exhibit extended circulation time and metabolic capabilities. In addition, the photothermal therapy/photoelectric therapy combination can significantly augment the effectiveness (ca. 72%) of thrombolysis. Consequently, the precisely delivered drug and the resultant phototherapeutic-driven heat-shock protein, immunomodulatory, anti-inflammatory, and inhibitory plasminogen activator inhibitor-1 (PAI-1) activities can restore vessels and effectively prevent rethrombosis. The described biomimetic P6@PEDOT@PLT nanomotors represent a promising option for improving the efficacy of antithrombotic therapy in thrombus-related illnesses.


Assuntos
Trombose , Ativador de Plasminogênio Tecidual , Humanos , Ativador de Plasminogênio Tecidual/farmacologia , Biomimética , Distribuição Tecidual , Trombose/tratamento farmacológico , Terapia Trombolítica/métodos
5.
J Org Chem ; 88(11): 7141-7151, 2023 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-37167441

RESUMO

Regioselective functionalization of unprotected carbohydrates at a secondary OH group in the presence of primary OH groups based on the commonly used organotin-mediated reaction has been improved. We found that the preactivation of the dibutylstannylene acetal intermediate with tetrabutylammonium bromide in toluene is a key to the improved condition for the efficient, high-yielding, and regioselective tosylation, benzoylation, or benzylation of unprotected carbohydrates. The counteranion of tetrabutylammonium ion with a weak coordination ability plays a crucial role in the improved regioselective reactions. A convenient access to the intermediates of synthetic value is also demonstrated in the organotin-mediated regioselective tosylation of unprotected carbohydrates, followed by the nucleophilic inversion reaction to give sulfur-containing and azide-modified carbohydrates.

6.
Foot Ankle Surg ; 29(1): 86-89, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36328920

RESUMO

BACKGROUND: This study examined the functional and clinical outcomes of subacute two stage metatarsal lengthening with gradual distraction for brachymetatarsia. This technique was developed to overcome the disadvantages of one-stage metatarsal lengthening and gradual distraction. METHODS: Four feet of three patients with congenital brachymetatarsia underwent subacute two stage metatarsal lengthening with gradual distraction. Pain, function, and alignment were assessed preoperatively and at follow-ups using the American Orthopaedic Foot and Ankle Society (AOFAS) lesser metatarsophalangeal-interphalangeal scale, and any complications were recorded. RESULTS: The patients were followed up for a mean of 18.1 ± 6.9 (range, 12.6-28.1) months. The mean metatarsal length gain was 15.2 ± 3.2 (range, 12.1-18.5) mm, and the corresponding percent increase was 32.5 % ± 7.0 % (range, 25.7-41.1 %). The mean AOFAS score (0-100) was 97.5 ± 5.0 at the final follow-up. The external fixator index was 10.2 ± 1.5 (range, 8.1-11.6) days/cm. None of the patients experienced metatarsophalangeal stiffness, subluxation or dislocation of the metatarsophalangeal joint, loss of correction, pin tract infection, delayed union, nonunion, or angular deformities. CONCLUSION: Subacute two stage metatarsal lengthening with gradual distraction is a reliable alternative treatment for brachymetatarsia.


Assuntos
Deformidades Congênitas do Pé , Luxações Articulares , Ossos do Metatarso , Articulação Metatarsofalângica , Osteogênese por Distração , Humanos , Osteogênese por Distração/efeitos adversos , Ossos do Metatarso/diagnóstico por imagem , Ossos do Metatarso/cirurgia , Ossos do Metatarso/anormalidades , Fixadores Externos , Deformidades Congênitas do Pé/diagnóstico por imagem , Deformidades Congênitas do Pé/cirurgia , Articulação Metatarsofalângica/diagnóstico por imagem , Articulação Metatarsofalângica/cirurgia , Luxações Articulares/etiologia
7.
Sci Rep ; 12(1): 21730, 2022 12 16.
Artigo em Inglês | MEDLINE | ID: mdl-36526655

RESUMO

Alluvial fans are large-scale depositional structures commonly found at the base of mountain ranges. They are relatively soil-rich compared to the rocky terrains, or catchment areas, from which their material originates. When frequented by debris flows (massive, muddy, rocky flows) they contribute significantly to local hazards as they carry focused, collisional, fast-moving materials across alluvial fans, unpredictable in size, speed, and direction. We research how fine particle content in debris flows correlates with directional changes, i.e., debris flow avulsions. Toward this, we analyzed field data from two neighboring alluvial fans in the White Mountains (California, USA) that exhibit dramatically different topographies despite their proximity and associated similar long-term climates. Informed by these measurements, we performed long-term and incremental alluvial fan experiments built by debris flows with systematically-varied fine particle content. We found that (1) decreasing fine particle content increases the variability of fan slopes and associated channelization dynamics, and (2) for all mixtures longer-term continuous alluvial fan experiments form more complex surface channelizations than repeated flows for the same total time, indicating the importance of both particle sizes and timescales on alluvial fan surface morphology.


Assuntos
Solo , Tamanho da Partícula
8.
Int J Mol Sci ; 22(21)2021 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-34769496

RESUMO

The role of the epithelial-mesenchymal transition (EMT) in lung epithelial cells is increasingly being recognized as a key stage in the development of COPD, fibrosis, and lung cancers, which are all highly associated with cigarette smoking and with exposure to second-hand smoke. Using the exposure of human lung cancer epithelial A549 cells and non-cancerous Beas-2B cells to sidestream cigarette smoke extract (CSE) as a model, we studied the protective effects of adipose-derived stem cell-conditioned medium (ADSC-CM) against CSE-induced cell death and EMT. CSE dose-dependently induced cell death, decreased epithelial markers, and increased the expression of mesenchymal markers. Upstream regulator analysis of differentially expressed genes after CSE exposure revealed similar pathways as those observed in typical EMT induced by TGF-ß1. CSE-induced cell death was clearly attenuated by ADSC-CM but not by other control media, such as a pass-through fraction of ADSC-CM or A549-CM. ADSC-CM effectively inhibited CSE-induced EMT and was able to reverse the gradual loss of epithelial marker expression associated with TGF-ß1 treatment. CSE or TGF-ß1 enhanced the speed of A549 migration by 2- to 3-fold, and ADSC-CM was effective in blocking the cell migration induced by either agent. Future work will build on the results of this in vitro study by defining the molecular mechanisms through which ADSC-CM protects lung epithelial cells from EMT induced by toxicants in second-hand smoke.


Assuntos
Fumar Cigarros/efeitos adversos , Neoplasias Pulmonares/prevenção & controle , Pulmão/efeitos dos fármacos , Células-Tronco Mesenquimais/citologia , Morte Celular/efeitos dos fármacos , Linhagem Celular , Linhagem Celular Tumoral , Meios de Cultivo Condicionados , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Transição Epitelial-Mesenquimal , Humanos , Pulmão/metabolismo , Pulmão/patologia , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Células-Tronco Mesenquimais/metabolismo , Doença Pulmonar Obstrutiva Crônica/metabolismo , Doença Pulmonar Obstrutiva Crônica/patologia , Doença Pulmonar Obstrutiva Crônica/prevenção & controle , Transdução de Sinais , Fumaça/efeitos adversos
9.
Int J Mol Sci ; 21(21)2020 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-33142808

RESUMO

Polyethylene glycol (PEG) coating of gold nanoparticles (AuNPs) improves AuNP distribution via blood circulation. The use of PEG-coated AuNPs was shown to result in acute injuries to the liver, kidney, and spleen, but long-term toxicity has not been well studied. In this study, we investigated reporter induction for up to 90 days in NF-κB transgenic reporter mice following intravenous injection of PEG-coated AuNPs. The results of different doses (1 and 4 µg AuNPs per gram of body weight), particle sizes (13 nm and 30 nm), and PEG surfaces (methoxyl- or carboxymethyl-PEG 5 kDa) were compared. The data showed up to 7-fold NF-κB reporter induction in mouse liver from 3 h to 7 d post PEG-AuNP injection compared to saline-injected control mice, and gradual reduction to a level similar to control by 90 days. Agglomerates of PEG-AuNPs were detected in liver Kupffer cells, but neither gross pathological abnormality in liver sections nor increased activity of liver enzymes were found at 90 days. Injection of PEG-AuNPs led to an increase in collagen in liver sections and elevated total serum cholesterol, although still within the normal range, suggesting that inflammation resulted in mild fibrosis and affected hepatic function. Administrating PEG-AuNPs inevitably results in nanoparticles entrapped in the liver; thus, further investigation is required to fully assess the long-term impacts by PEG-AuNPs on liver health.


Assuntos
Ouro/química , Inflamação/patologia , Fígado/patologia , Nanopartículas Metálicas/toxicidade , NF-kappa B/genética , Polietilenoglicóis/química , Animais , Inflamação/induzido quimicamente , Inflamação/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Luciferases , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , NF-kappa B/metabolismo
10.
J Chin Med Assoc ; 83(9): 858-864, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32371666

RESUMO

BACKGROUND: Evidences that support the use of targeted temperature management (TTM) for in-hospital cardiac arrest (IHCA) are lacking. We aimed to investigate the hypothesis that TTM benefits for patients with IHCA are similar to those with out-of-hospital cardiac arrest (OHCA) and to determine the independent predictors of resuscitation outcomes in patients with cardiac arrest receiving subsequent TTM. METHODS: This is a retrospective, matched, case-control study (ratio 1:1) including 93 patients with IHCA treated with TTM after the return of spontaneous circulation, who were admitted to Partners HealthCare system in Boston from January 2011 to December 2018. Controls were defined as the same number of patients with OHCA, matched for age, Charlson score, and sex. Survival and neurological outcomes upon discharge were the primary outcome measures. RESULTS: Patients with IHCA were more likely to have experienced a witnessed arrest and receive bystander cardiopulmonary resuscitation, a larger total dosage of epinephrine, and extracorporeal membrane oxygenation. The time duration for ROSC was shorter in patients with IHCA than in those with OHCA. The IHCA group was more likely associated with mild thrombocytopenia during TTM than the OHCA group. Survival after discharge and favorable neurological outcomes did not differ between the two groups. Among all patients who had cardiac arrest treated with TTM, the initial shockable rhythm, time to ROSC, and medical history of heart failure were independent outcome predictors for survival to hospital discharge. The only factor to predict favorable neurological outcomes at discharge was initial shockable rhythm. CONCLUSION: The beneficial effects of TTM in eligible patients with IHCA were similar with those with OHCA. Initial shockable rhythm was the only independent predictor of both survival and favorable neurological outcomes at discharge in all cardiac arrest survivors receiving TTM.


Assuntos
Parada Cardíaca/terapia , Hipotermia Induzida , Parada Cardíaca Extra-Hospitalar/terapia , Idoso , Idoso de 80 Anos ou mais , Feminino , Parada Cardíaca/mortalidade , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Parada Cardíaca Extra-Hospitalar/mortalidade , Estudos Retrospectivos
11.
Colloids Surf B Biointerfaces ; 187: 110644, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31757445

RESUMO

Protein microparticles have received attention as drug delivery systems because of their high protein stability and prolonged release in vivo. However, most current preparation processes introduce chemical crosslinkers, which often lead to protein inactivation and limit drug efficacy in delivery systems. In this study, we employed the well-known hexahistidine (His)-tag recombinant protein technology and a metal-triggerable collagen-mimetic peptide to enhance the binding strength between the protein and metal ion and fine-tuned the protein drug release. His-tagged proteins self-assembled to form microparticles (∼2 µm) upon zinc ion treatment and sustained protein drug release was achieved in physiological saline. The results also indicated that by adjusting the peptide concentration and N- and C-terminal hexahistidine-tags, protein release could be controlled. Moreover, no protein denaturation was observed. We developed a universal strategy for facile protein microparticle fabrication under mild conditions and we demonstrated its potential as a therapeutics formulation with tunable protein release.


Assuntos
Histidina/química , Microesferas , Oligopeptídeos/química , Peptídeos/química , Proteínas/química , Zinco/química , Colágeno/química , Proteínas de Fluorescência Verde/química , Tamanho da Partícula
12.
Int J Syst Evol Microbiol ; 69(11): 3318-3325, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30422104

RESUMO

Two isolates of heterotrophic, facultatively anaerobic, marine bacteria, designated DM1 and DM2T, were recovered from a lagoon sediment sample of Dongsha Island, Taiwan. Cells were Gram-reaction-negative rods. Nearly all of the cells were non-motile and non-flagellated during the late exponential to early stationary phase of growth, while a few of the cells exhibited motility with monotrichous flagellation. The two isolates required NaCl for growth and grew optimally at about 30 °C, 2-3 % NaCl and pH 7-8. They grew aerobically and could achieve anaerobic growth by fermenting d-glucose or other carbohydrates with production of acids and the gases, including CO2 and H2. Ubiquinone Q-8 was the only respiratory quinone. Cellular fatty acids were predominated by C16 : 0, C18 : 1ω7c and C16 : 1ω7c. The major polar lipid was phosphatidylethanolamine. Strains DM1 and DM2T had DNA G+C contents of 52.0 and 51.8 mol%, respectively, as determined by HPLC analysis. Phylogenetic analyses based on 16S rRNA gene sequences clearly indicated that the two isolates formed a distinct genus-level lineage in the family Aeromonadaceae of the class Gammaproteobacteria and was an outgroup with respect to a stable supragenic clade comprising species of the genera Oceanimonas, Oceanisphaera and Zobellella. The phylogenetic data and those from chemotaxonomic, physiological and morphological characterizations support the establishment of a novel species and genus inside the family Aeromonadaceae, for which the name Dongshaea marina gen. nov., sp. nov. is proposed. The type strain is DM2T (=BCRC 81069T=JCM 32096T).


Assuntos
Aeromonadaceae/classificação , Sedimentos Geológicos/microbiologia , Glucose/metabolismo , Filogenia , Água do Mar/microbiologia , Aeromonadaceae/isolamento & purificação , Anaerobiose , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Fermentação , Gases , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Taiwan , Ubiquinona/química
13.
J Food Drug Anal ; 26(1): 353-361, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29389574

RESUMO

Low bioavailability and high binding affinity to plasma proteins led to the difficulty for the quantitative detection of lithospermate B (LSB) in plasma. This study aimed to develop a protocol for detecting LSB in plasma. A method was employed to quantitatively detect LSB of 5-500 ng/mL by LC/MS spectrometry in multi reaction monitoring mode via monitoring two major fragments with m/z values of 519 and 321 in the MS2 spectrum. To set up an adequate extraction solution to release LSB captured by plasma proteins, recovery yields of LSB extracted from rat plasma acidified by formic acid or HCl in the presence or absence of EDTA and caffeic acid were detected and compared using the above quantitative method. High recovery yield (∼90%) was achieved when LSB (5-500 ng/mL) mixed in rat plasma was acidified by HCl (5 M) in the presence of EDTA (0.5 M) and caffeic acid (400 µg/mL). The lower limit of detection and the lower limit of quantification for LSB in the spiked plasma were calculated to be 1.8 and 5.4 ng/mL, respectively. Good accuracy (within ±10%) and precision (less than 10%) of intra- and inter-day quality controlled samples were observed. Oral bioavailability of LSB in rat model was detected via this optimized extraction method, and the maximum plasma concentration (Cmax) was found to be 1034.3 ± 510.5 µg/L at tmax around 10 min, and the area under the plasma concentration-time curve (AUC) was 1414.1 ± 851.2 µg·h/L.


Assuntos
Cromatografia Líquida , Medicamentos de Ervas Chinesas/farmacocinética , Espectrometria de Massas , Administração Oral , Animais , Disponibilidade Biológica , Medicamentos de Ervas Chinesas/administração & dosagem , Medicamentos de Ervas Chinesas/química , Masculino , Estrutura Molecular , Ligação Proteica , Ratos , Reprodutibilidade dos Testes
14.
Phys Rev E ; 96(6-1): 062601, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29347344

RESUMO

The mesoscopic collective motion of self-propelling active particle suspension is experimentally investigated. The active particles are silica micro spheres with Au hemisphere coating, and their propelling strength is activated by laser irradiation. The suspension is driven from equilibrium to near equilibrium and far from equilibrium by tuning the excitation laser intensity. By use of the long-term particle tracking technique, the time evolution of a large amount of active particles is resolvable. For low laser intensity, the suspension is driven to near equilibrium state with homogeneous superdiffusion motion. The strength of enhanced superdiffusion is monotonically related to the laser intensity. For high laser intensity, the motility-induced phase separation with the coexistence of dense cluster and very dilute individual particle are observed. It leads to highly heterogeneous dynamic with less mobile jammed cluster and fast-moving particles and subsequently suppresses the enhanced superdiffusion. Such heterogeneous dynamics is similar to many far from equilibrium systems. Finally, the degree away from equilibrium (Gaussian dynamics) triggered by propelling strength is quantified by non-Gaussian parameters.

15.
Oncotarget ; 7(34): 54274-54289, 2016 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-27494843

RESUMO

Proteinopathy in the heart which often manifests excessive misfolded/aggregated proteins in cardiac myocytes can result in severe fibrosis and heart failure. Here we developed a mouse model, which transgenically express tetrameric DsRed, a red fluorescent protein (RFP), in an attempt to mimic the pathological mechanisms ofcardiac fibrosis. Whilst DsRed is expressed and forms aggregation in most mouse organs, certain pathological defects are specifically recapitulated in cardiac muscle cells including mitochondria damages, aggresome-like residual bodies, excessive ubiquitinated proteins, and the induction of autophagy. The proteinopathy and cellular injuries caused by DsRed aggregates may be due to impaired or overburdened ubiquitin-proteasome system and autophagy-lysosome systems. We further identified that DsRed can be ubiquitinated and associated with MuRF1, a muscle-specific E3 ligase. Concomitantly, an activation of NF-κB signaling and a strong TIMP1 induction were noted, suggesting that RFP-induced fibrosis was augmented by a skewed balance between TIMP1 and MMPs. Taken together, our study highlights the molecular consequences of uncontrolled protein aggregation leading to congestive heart failure, and provides novel insights into fibrosis formation that can be exploited for improved therapy.


Assuntos
Autofagia , Proteínas Luminescentes/química , Miocárdio/patologia , Complexo de Endopeptidases do Proteassoma/metabolismo , Animais , Fibrose , Insuficiência Cardíaca/etiologia , Camundongos , Músculo Esquelético/patologia , Agregados Proteicos , Inibidor Tecidual de Metaloproteinase-1/fisiologia , Ubiquitina-Proteína Ligases/fisiologia , Ubiquitinação
16.
Chemosphere ; 159: 412-419, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27337432

RESUMO

There were considerable concerns about the zinc (Zn) pollution caused by electroplating, chemical, and computer-related high-tech industrial discharges in Kaohsiung Rivers situated at south Taiwan. There is, however, a lack of site-specific water chemistry based toxicity assessment and little is known about the sublethal toxicity on freshwater fish. This study proposes an integrated framework to link experimental and mechanistic model-based data analysis of lethal and sublethal Zn toxicities for grass carp (Ctenopharyn odon idellus) populations for providing the site-specific Zn water quality threshold in Kaohsiung Rivers. A biotic ligand model (BLM) that relates toxicity impairment of physiological active sites impacted by Zn species was used to elucidate the site-specific water chemistry affecting the bioavailability and biological response of grass carp exposed to Zn. Results indicated that 96-h LC50 for mortality and 28-d EC50 for growth inhibition were 474.7 ± 1.3 (mean ± SE) and 149 ± 23.5 µg L(-1), respectively. Here the BLM-based predicted steady-state LC50s for mortality were 2110.7, 818.2, 1303.6, 563.3, and 497.1 µg L(-1), whereas measured steady-state EC50s for growth inhibition were 726.8, 326.2, 373.4, 193.9, and 170.5 µg L(-1) for the Agongdian, Houling, Love, Fengshan, and Gaoping Rivers, respectively. A positive correlation between Mg(2+) and EC50 values were found in both acute (r = 0.94, p < 0.01) and chronic (r = 0.97, p < 0.01) Zn exposures. This study suggests that the use of site-specific water chemistry data and ecophysiological traits would enhance the predictive capacities to assess the potential effect of metal toxicity posed to aquatic organisms.


Assuntos
Carpas/crescimento & desenvolvimento , Rios/química , Poluentes Químicos da Água/toxicidade , Zinco/toxicidade , Animais , Dose Letal Mediana , Modelos Teóricos , Taiwan , Poluentes Químicos da Água/análise , Qualidade da Água , Zinco/análise
17.
Sci Rep ; 6: 26358, 2016 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-27198537

RESUMO

Men have worse survival than premenopausal women after intracerebral hemorrhage (ICH). After ICH, overproduction of iron associated with induction of heme oxygenase-1 (HO-1) in brain was observed. Rodent ICH model using ferrous citrate (FC)-infusion into the striatum to simulate iron overload, showed a higher degree of injury severity in males than in females. However, the participation of HO-1 in sex-differences of iron-induced brain injury remains unknown. The present results showed a higher level of HO-1 expression associated with more severe injury in males compared with females after FC-infusion. Estradiol (E2) contributed to lower levels of FC-induced HO-1 expression in females compared with males. Heterozygote ho-1 KO decreased the levels of FC-induced injury severity, histological lesions, behavioral deficits, autophagy and autophagic cell death in the striatum of males but not in females. Moreover, ho-1 deficiency enhanced the neuroprotection by E2 only in males. These results suggested that over induction of HO-1 plays a harmful role in FC-induced brain injury in a male-specific manner. Suppression of HO-1 combined with E2 exhibits a synergistic effect on neuroprotection against FC-induced striatal injury in males. These findings open up the prospect for male-specific neuroprotection targeting HO-1 suppression for patients suffering from striatal iron overload.


Assuntos
Hemorragia Cerebral/metabolismo , Corpo Estriado/citologia , Compostos Ferrosos/toxicidade , Heme Oxigenase-1/genética , Heme Oxigenase-1/metabolismo , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Animais , Apoptose , Hemorragia Cerebral/tratamento farmacológico , Hemorragia Cerebral/etiologia , Hemorragia Cerebral/genética , Ácido Cítrico , Corpo Estriado/efeitos dos fármacos , Corpo Estriado/metabolismo , Modelos Animais de Doenças , Estradiol/administração & dosagem , Estradiol/farmacologia , Feminino , Compostos Ferrosos/administração & dosagem , Masculino , Camundongos , Camundongos Knockout , Índice de Gravidade de Doença , Caracteres Sexuais , Regulação para Cima
18.
Biomed Res Int ; 2015: 539805, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26504810

RESUMO

Mitochondrial heat shock proteins, such as HSP60, are chaperones responsible for the folding, transport, and quality control of mitochondrial matrix proteins and are essential for maintaining life. Both prosurvival and proapoptotic roles have been proposed for HSP60, and HSP60 is reportedly involved in the initiation of autoimmune, metabolic, and cardiovascular diseases. The role of HSP60 in pathogenesis of these diseases remains unclear, partly because of the lack of mouse models expressing HSP60. In this study we generated HSP60 conditional transgenic mice suitable for investigating in vivo outcomes by expressing HSP60 at the targeted organ in disease models. Ubiquitous HSP60 induction in the embryonic stage caused neonatal death in mice at postnatal day 1. A high incidence of atrial septal defects was observed in HSP60-expressing mice, with increased apoptosis and myocyte degeneration that possibly contributed to massive hemorrhage and sponge-like cardiac muscles. Our results showed that neonatal heart failure through HSP60 induction likely involves developmental defects and excessive apoptosis. The conditional HSP60 mouse model is useful for studying crucial biological questions concerning HSP60.


Assuntos
Chaperonina 60/genética , Insuficiência Cardíaca/etiologia , Proteínas Mitocondriais/genética , Animais , Animais Recém-Nascidos , Apoptose/genética , Chaperonina 60/metabolismo , Modelos Animais de Doenças , Feminino , Insuficiência Cardíaca/congênito , Insuficiência Cardíaca/genética , Comunicação Interatrial/genética , Comunicação Interatrial/metabolismo , Comunicação Interatrial/patologia , Imuno-Histoquímica , Imageamento por Ressonância Magnética , Camundongos , Camundongos Transgênicos , Microscopia Eletrônica de Transmissão , Proteínas Mitocondriais/metabolismo , Miocárdio/metabolismo , Miocárdio/patologia , Gravidez , Regulação para Cima
19.
PLoS One ; 10(7): e0131224, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26147959

RESUMO

Men exhibit a worse survival rate than premenopausal women after intracerebral hemorrhage (ICH), however, no sex-specific management has been concerned. In a rat model involving infusion of ferrous citrate (FC) that simulates iron accumulation after hemorrhage, a higher degree of autophagy associated with higher injury severity was observed in striatum of males than in females. Since the imbalance between the levels of autophagy and energy demand may lead to cell death, we proposed that FC-induced autophagy is detrimental in a male specific manner and autophagy modulation affects injury severity in a sex-dependent manner. Rapamycin, an autophagy inducer, and conditional knockout gene of autophagy-related protein 7 (Atg7) in dopamine receptor D2 (DRD2) neurons were used to test our hypothesis using a mouse model with striatal FC infusion. The result showed that the levels of autophagic cell death and injury severity were higher in male than in female mice. Pre-treatment of FC-infused females with rapamycin increased the FC-induced behavioral deficit and DRD2 neuron death. However, DRD2 neuron-specific knockout of Atg7 decreased FC-induced injury severity and the number of TUNEL(+) DRD2 neurons in males. These results suggest that autophagy in FC-infusion males is overactive with maladaptive consequences and inhibition of autophagy decreases the severity of FC-induced striatal injury in males. These findings present prospects for male-specific therapeutic strategy that targets autophagy in patients suffering from iron overload.


Assuntos
Autofagia/efeitos dos fármacos , Corpo Estriado/efeitos dos fármacos , Ferro/toxicidade , Animais , Proteína 7 Relacionada à Autofagia , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Proteínas Associadas aos Microtúbulos/genética
20.
Small ; 10(5): 895-900, 2014 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-24170526

RESUMO

Electroactive MoSx catalysts on porous 3D sponges synthezied by a simple and scalable thermolysis process are proposed. Although no conducting materials are used to host the MoSx catalysts, they still serve as efficient electrodes for hydrogen evolution. The high current density of the MoSx-coated sponges are attributed to the large electrochemical surface area and their S-rich chemical structure.

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