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1.
Hum Mol Genet ; 31(14): 2396-2405, 2022 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-35179198

RESUMO

Cognitive impairment is a common non-motor complication of Parkinson's disease (PD). Glucocerebrosidase gene (GBA1) variants are found in 10-15% of PD cases and are numerically the most important risk factor for PD and dementia with Lewy bodies. Accumulation of α-synuclein and tau pathology is thought to underlie cognitive impairment in PD and likely involves cholinergic as well as dopaminergic neurons. Neural crest stem cells were isolated from both PD patients with the common heterozygous N370S GBA1 mutation and normal subjects without GBA1 mutations. The stem cells were used to generate a cholinergic neuronal cell model. The effects of the GBA1 variant on glucocerebrosidase (GCase) protein and activity, and cathepsin D, tau and α-synuclein protein levels in cholinergic neurons were examined. Ambroxol, a GCase chaperone, was used to investigate whether GCase enhancement was able to reverse the effects of the GBA1 variant on cholinergic neurons. Significant reductions in GCase protein and activity, as well as in cathepsin D levels, were found in GBA1 mutant (N370S/WT) cholinergic neurons. Both tau and α-synuclein levels were significantly increased in GBA1 mutant (N370S/WT) cholinergic neurons. Ambroxol significantly enhanced GCase activity and decreased both tau and α-synuclein levels in cholinergic neurons. GBA1 mutations interfere with the metabolism of α-synuclein and tau proteins and induce higher levels of α-synuclein and tau proteins in cholinergic neurons. The GCase pathway provides a potential therapeutic target for neurodegenerative disorders related to pathological α-synuclein or tau accumulation.


Assuntos
Ambroxol , Glucosilceramidase , Doença de Parkinson , Ambroxol/farmacologia , Catepsina D/genética , Células Cultivadas , Colinérgicos/farmacologia , Glucosilceramidase/genética , Humanos , Mutação , Doença de Parkinson/genética , Doença de Parkinson/metabolismo , alfa-Sinucleína/genética , alfa-Sinucleína/metabolismo , Proteínas tau/genética , Proteínas tau/metabolismo
2.
Parasitol Res ; 121(6): 1639-1649, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35412077

RESUMO

This study investigated the role of calpain in Eimeria tenella-induced host cell apoptosis. Chick embryo cecal epithelial cell culture technology, flow cytometry, enzyme-linked immunosorbent assays, and fluorescence quantitative PCR were used to detect the E. tenella host cell apoptotic rate, Bax and Bid expression levels, and calpain activity. The results demonstrated that Bax, Bid, and calpain levels were upregulated and apoptosis was increased following E. tenella infection at 24-120 h. Calpain levels were reduced by pharmacological inhibition of calpain using SJA6017 or by blocking Ca2+ entry into the cell using BAPTA/AM at 24-120 h. The mRNA and protein levels of Bax and Bid, the E. tenella infection rate, and the early apoptotic and late apoptotic (necrosis) rates were decreased by using SJA6017 at 24-120 h. These results indicated that E. tenella-promoted host cell apoptosis is regulated by calpain via Bid and Bax at 24-120 h. Thus, manipulation of calpain levels could be used to manage E. tenella infection in chickens in the middle and late developmental stages.


Assuntos
Coccidiose , Eimeria tenella , Doenças das Aves Domésticas , Animais , Apoptose , Calpaína/genética , Embrião de Galinha , Galinhas , Coccidiose/metabolismo , Coccidiose/veterinária , Eimeria tenella/genética , Doenças das Aves Domésticas/genética , Proteína X Associada a bcl-2/genética
3.
J Minim Access Surg ; 18(3): 327-337, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35708376

RESUMO

Objective: To systematically evaluate the application effect of endoscopic papillary balloon dilatation (EPBD) with different balloon dilatation duration for biliary duct calculi, and find the most appropriate dilatation duration for EPBD using a network meta-analysis. Materials and Methods: PubMed, Embase and Cochrane Library databases were searched for relevant randomised controlled trials (RCTs) published up to August 2020. Node split, consistency and inconsistency models analysis were all conducted in network meta-analysis. Results: Eighteen RCTs with 2256 participants were finally analysed. EPBD was divided into four categories based on balloon dilatation duration, including EPBD (P0.5), EPBD (>0.5, ≤1), EPBD (1, ≤2) and EPBD (>2, ≤5). Compared with EPBD (>0.5, ≤1), EPBD (>2, ≤5) had a lower risk of early complications (odds ratio [OR] = 0.23, 95% credible interval [CI] = 0.05-0.96) and post-endoscopic procedure pancreatitis (PEP) (OR = 0.17, 95% CI = 0.03-0.72). Endoscopic sphincterotomy (EST) tended to have less need for mechanical lithotripsy (OR = 0.37, 95% CI = 0.16-0.88) and PEP (OR = 0.26, 95% CI = 0.08-0.71) than EPBD (>0.5, ≤1). EPBD (>2, ≤5) was the safest endoscopic procedure with respect to early complications (surface area under cumulative ranking curves [SUCRA] = 79.0) and PEP (SUCRA = 85.3). In addition, EPBD (>2, ≤5) and EST had the highest probability of being the best (SUCRA = 82.6) and the worst (SUCRA = 10.8), respectively, regarding late complications. Conclusion: EPBD and EST are two methods used to treat uncomplicated choledocholithiasis (stone diameter <10 mm and stone number <3). The extension of balloon dilatation duration has no significant influence on successful stone removal in the first endoscopic session or preventing the need for mechanical lithotripsy. However, it can reduce the risk of early complications, especially PEP. What's more, EPBD seems to have less late complications compared with EST, and the effect of prolonged balloon dilatation duration on late complications still needs to be further explored. Therefore, 2-5 min is the recommended dilatation duration range for EPBD using balloon with ≤10 mm diameter. Further research based on a specific population and with a longer follow-up time are needed.

4.
Neurobiol Dis ; 134: 104620, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31634558

RESUMO

The presence of GBA1 gene mutations increases risk for Parkinson's disease (PD), but the pathogenic mechanisms of GBA1 associated PD remain unknown. Given that impaired α-synuclein turnover is a hallmark of PD pathogenesis and cathepsin D is a key enzyme involved in α-synuclein degradation in neuronal cells, we have examined the relationship of glucocerebrosidase (GCase), cathepsin D and monomeric α-synuclein in human neural crest stem cell derived dopaminergic neurons. We found that normal activity of GCase is necessary for cathepsin D to perform its function of monomeric α-synuclein removal from neurons. GBA1 mutations lead to a lower level of cathepsin D protein and activity, and higher level of monomeric α-synuclein in neurons. When GBA1 mutant neurons were treated with GCase replacement or chaperone therapy; cathepsin D protein levels and activity were restored, and monomeric α-synuclein decreased. When cathepsin D was inhibited, GCase replacement failed to reduce monomeric α-synuclein levels in GBA1 mutant neurons. These data indicate that GBA1 gene mutations increase monomeric α-synuclein levels via an effect on lysosomal cathepsin D in neurons.


Assuntos
Catepsina D/metabolismo , Neurônios Dopaminérgicos/metabolismo , Glucosilceramidase/metabolismo , Doença de Parkinson , alfa-Sinucleína/metabolismo , Células Cultivadas , Glucosilceramidase/genética , Humanos , Mutação , Crista Neural , Células-Tronco Neurais , Doença de Parkinson/metabolismo , Doença de Parkinson/patologia
5.
Mol Cell Probes ; 46: 101411, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31173881

RESUMO

We aimed to develop a high-throughput deep DNA sequencing assay of cerebrospinal fluid (CSF) to identify clinically relevant oncogenic mutations that contribute to the development of glioblastoma (GBM) and serve as biomarkers to predict patients' responses to surgery. For this purpose, we recruited five patients diagnosed with highly suspicious GBM according to preoperative magnet resonance imaging. Subsequently, patients were histologically diagnosed with GBM. CSF was obtained through routine lumbar puncture, and plasma from peripheral blood was collected before surgery and 7 days after. Fresh tumor samples were collected using routine surgical procedures. Targeted deep sequencing was used to characterize the genomic landscape and identify mutational profile that differed between pre-surgical and post-surgical samples. Sequence analysis was designed to detect protein-coding exons, exon-intron boundaries, and the untranslated regions of 50 genes associated with cancers of the central nervous system. Circulating tumor DNAs (ctDNAs) were prepared from the CSF and plasma from peripheral blood. For comparison, DNA was isolated from fresh tumor tissues. Non-silent coding variants were detected in CSF and plasma ctDNAs, and the overall minor allele frequency (MAF) of the former corresponded to an earlier disease stage compared with that of plasma when the tumor burden was released (surgical removal). Gene mutation loads of GBMs significantly correlated with overall survival (OS, days) (Pearson correlation = -0.95, P = 0.01). We conclude that CSF ctDNAs better reflected the sequential mutational changes of driver genes compared with those of plasma ctDNAs. Deep sequencing of the CSF of patients with GBM may therefore serve as an alternative clinical assay to improve patients' outcomes.


Assuntos
Biomarcadores Tumorais/genética , DNA Tumoral Circulante/genética , Glioblastoma/genética , Proteínas de Neoplasias/genética , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/sangue , Biomarcadores Tumorais/líquido cefalorraquidiano , DNA Tumoral Circulante/sangue , DNA Tumoral Circulante/líquido cefalorraquidiano , Intervalo Livre de Doença , Feminino , Glioblastoma/sangue , Glioblastoma/líquido cefalorraquidiano , Glioblastoma/patologia , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Proteínas de Neoplasias/sangue , Proteínas de Neoplasias/líquido cefalorraquidiano , Resultado do Tratamento
6.
Bioconjug Chem ; 26(12): 2384-96, 2015 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-26439600

RESUMO

Quantum dots (QDs) are fluorescent nanoparticles with unique photophysical properties that enable them to potentially replace traditional organic dyes and fluorescent proteins in various bioimaging applications. However, the inherent toxicity of their cores based on cadmium salts limits their widespread biomedical use. We have developed a novel nanocomposite polymer emulsion based on polyhedral oligomeric silsesquioxane poly(carbonate-urea) urethane (POSS-PCU) that can be used to coat quantum dots to nullify their toxicity and enhance photostability. Here we report the synthesis and characterization of a novel POSS-PCU nanocomposite polymer emulsion and describe its application for coating QDs for biological application. The polymer was synthesized by a process of emulsion polymerization and formed stable micelles of ∼33 nm in diameter. CdTe/CdS/ZnS QDs were efficiently stabilized by the polymer emulsion through encapsulation within the polymer micelles. Characterization studies showed no significant change in the unique photophysical properties of QDs after coating. The polymer was biocompatible to HepG2, HUVECs, and mouse skeletal muscle cells at 2.5% after 24 h exposure on in vitro testing. Polymer encapsulated QDs showed enhanced photostability on exposure to high degrees of UV irradiation and air as well as significantly reduced cytotoxicity on exposure to HepG2 cells at 30 µg/mL for 24 h. We have therefore concluded that the POSS-PCU polymer emulsion has the potential to make a biocompatible and photostable coating for QDs enabling a host of biomedical applications to take this technology to the next level.


Assuntos
Materiais Biocompatíveis/química , Nanocompostos/química , Pontos Quânticos/química , Animais , Materiais Biocompatíveis/toxicidade , Células Cultivadas , Emulsões/química , Emulsões/toxicidade , Células Hep G2 , Células Endoteliais da Veia Umbilical Humana , Humanos , Teste de Materiais , Camundongos , Nanocompostos/toxicidade , Nanocompostos/ultraestrutura , Fotólise , Pontos Quânticos/toxicidade , Pontos Quânticos/ultraestrutura , Raios Ultravioleta
7.
J Fungi (Basel) ; 10(1)2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-38248952

RESUMO

Most reported members of Microascaceae that have been reported originate from the terrestrial environment, where they act as saprobes or plant pathogens. However, our understanding of their species diversity and distribution in the marine environment remains vastly limited, with only 22 species in nine genera having been reported so far. A survey of the fungal diversity in intertidal areas of China's mainland has revealed the discovery of several Microascaceae strains from 14 marine algae and 15 sediment samples. Based on morphological characteristics and LSU-ITS-tef1-tub2 multilocus phylogeny using Bayesian inference and maximum likelihood methods, 48 strains were identified as 18 species belonging to six genera. Among these, six new species were discovered: Gamsia sedimenticola, Microascus algicola, M. gennadii, Scedosporium ellipsosporium, S. shenzhenensis, and S. sphaerospermum. Additionally, the worldwide distribution of the species within this family across various marine habitats was briefly reviewed and discussed. Our study expands the knowledge of species diversity and distribution of Microascaceae in the marine environment.

8.
Foods ; 13(3)2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38338566

RESUMO

This research supplied a "cleaner-production" way to produce "clean-label" quinoa starch-based Pickering emulsifier with excellent emulsifying properties. The effects of dry ball-milling time and speed on the multi-scale structures and emulsifying properties of quinoa starch were studied. With increasing ball-milling time and speed, particle size first decreased and then increased, the crystallinity, lamellar structure and short-range ordered structure gradually decreased, and contact angle gradually increased. The increased contact angle might be related to the increased oil absorption properties and the decreased water content. The emulsification properties of ball-milled quinoa starch (BMQS)-based Pickering emulsions increased with the increase in ball-milling time and speed, and the emulsions of BMQS-4 h, 6 h, 8 h, and 600 r reached the full emulsification state. After 120 days' storage, the oil droplets of BMQS-2 h (BMQS-400 r) deformed, the oil droplets increased, and the emulsification index decreased. The emulsification index and the oil droplets of BMQS-4 h, 6 h, 8 h and 600 r-based emulsions did not show obvious changes after storage, indicating the good emulsifying stability of these BMQS-based emulsions, which might be because that the relatively larger amount of starch particles that dispersed in the voids among the oil droplets could act as stronger network skeletons for the emulsion gel. This Pickering emulsifier was easily and highly efficiently produced and low-cost, having great potential to be used in the food, cosmetic and pharmaceutical industries.

9.
Liver Int ; 32(4): 531-43, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22316165

RESUMO

Ischaemia reperfusion (IR) injury is a clinical entity with a major contribution to the morbidity and mortality of liver surgery and transplantation. A central pathway of protection against IR injury utilizes nitric oxide (NO). Nitric oxide synthase (NOS) enzymes manufacture NO from L-arginine. NO generated by the endothelial NOS (eNOS) isoform protects against liver IR injury, whereas inducible NOS (iNOS)-derived NO may have either a protective or a deleterious effect during the early phase of IR injury, depending on the length of ischaemia, length of reperfusion and experimental model. In late phase hepatic IR injury, iNOS-derived NO plays a protective role. In addition to NOS consumption of L-arginine during NO synthesis, this amino acid may also be metabolized by arginase, an enzyme whose release is increased during prolonged ischaemia, and therefore diverts L-arginine away from NOS metabolism leading to a drop in the rate of NO synthesis. NO most commonly acts through the soluble guanylyl cyclase-cyclic GMP- protein kinase G pathway to ameliorate hepatic IR injury. Both endogenously generated and exogenously administered NO donors protect against liver IR injury. The beneficial effects of NO on liver IR are not, however, universal, and certain conditions, such as steatosis, may influence the protective effects of NO. In this review, the evidence for, and mechanisms of these protective actions of NO are discussed, and areas in need of further research are highlighted.


Assuntos
Fígado/fisiopatologia , Redes e Vias Metabólicas/fisiologia , Modelos Biológicos , Óxido Nítrico Sintase Tipo II/metabolismo , Óxido Nítrico/metabolismo , Traumatismo por Reperfusão/prevenção & controle , Traumatismo por Reperfusão/fisiopatologia , Arginina/metabolismo , Humanos , Fígado/metabolismo , Traumatismo por Reperfusão/metabolismo
10.
ACS Omega ; 7(38): 33858-33865, 2022 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-36188310

RESUMO

Silver (Ag) has been demonstrated to have excellent performance to kill bacteria, fungi, and some viruses because it can release positively charged Ag ions with highly antibacterial and antifungal activities. However, effectively controlling the slow release of Ag ions is the key to preparing high-performance Ag-based antibacterial agents, which remains a challenge. In this work, we have developed a new Ag-based antibacterial agent composed of Ag ions loaded on 2D anionic 2D Sb3P2O14 3- nanosheets (denoted as Ag-Sb3P2O14). 2D anionic nanosheets not only adsorb a large amount of Ag ions but also control their slow release through electrostatic interaction between nanosheets and Ag ions. 2D Ag-Sb3P2O14 nanofillers enable excellent high antibacterial activities for the poly(vinylidene fluoride) (PVDF) film composites against microorganisms including Escherichia coli and Staphylococcus aureus. Moreover, the PVDF membrane with 5 wt % 2D Ag-Sb3P2O14 nanofillers can kill almost all bacterial after 50 times washing, demonstrating its excellent durable antibacterial activities. This work opens up a new and promising route to durable Ag-based antibacterial agents for polymer-based composites.

11.
Liver Transpl ; 17(5): 610-9, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21506249

RESUMO

Hindlimb remote ischemic preconditioning (RIPC) reduces liver ischemia/reperfusion (IR) injury in wild-type mice. The underlying mechanisms of RIPC are currently unknown. In this study, we investigated the role of endothelial nitric oxide synthase (eNOS) in mediating the protective effects of RIPC. Endothelial nitric oxide synthase knockout (eNOS(-/-) ) mice were divided into 4 groups: (1) a sham surgery group, (2) an RIPC group (6 cycles of 4 minutes of hindlimb ischemia and 4 minutes of hindlimb reperfusion), (3) an IR group [40 minutes of lobar (70%) hepatic ischemia and 2 hours of reperfusion], and (4) an RIPC+IR group (RIPC followed by the IR group procedures). Plasma liver aminotransferases, hepatic histopathological injury scores, transmission electron microscopy studies, and hepatic microcirculatory blood flow (MBF) were assessed. eNOS protein expression was analyzed in the livers and hindlimb muscles of wild-type mice. Hindlimb RIPC did not protect against subsequent liver IR injury in eNOS(-/-) mice; this was demonstrated by the lack of reduction in the plasma aminotransferase levels, histopathological scores, or ultrastructural features of IR injury in the RIPC+IR group versus the IR group. Hepatic MBF did not recover during liver reperfusion in the RIPC+IR group versus the IR group. eNOS protein expression was similar among all wild-type groups. In conclusion, eNOS is essential for the protective effects of hindlimb RIPC on liver IR injury. eNOS exerts its protective effects through the preservation of hepatic MBF. At 2 hours of reperfusion, eNOS protection is likely due to the increased activation of eNOS rather than increased expression.


Assuntos
Membro Posterior/fisiopatologia , Precondicionamento Isquêmico/métodos , Fígado/metabolismo , Óxido Nítrico Sintase Tipo III/fisiologia , Animais , Modelos Animais de Doenças , Imuno-Histoquímica/métodos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Microscopia Eletrônica de Transmissão/métodos , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo III/genética , Reperfusão , Traumatismo por Reperfusão
12.
Liver Transpl ; 17(1): 70-82, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21254347

RESUMO

Ischemic preconditioning of remote organs (RIPC) reduces liver ischemia/reperfusion (IR) injury in the rabbit and rat. Mice are the only species available with a large number of transgenic strains. This study describes development and validation of a mouse model of hindlimb RIPC that attenuates liver IR injury. Mice were allocated to 4 groups: (1) Sham surgery; (2) RIPC: 6 cycles of 4 × 4 minutes ischemia/reperfusion of hindlimb; (3) IR: 40 minutes lobar (70%) hepatic ischemia and 2 hours reperfusion; (4) RIPC+IR: RIPC followed by IR group procedures. Plasma liver aminotransferases and hepatic histopathological and transmission electron microscopy studies were performed at the end of the experiment. Hepatic microcirculatory blood flow was measured throughout the experiment. Postoperative complications and animal survival were evaluated. Hindlimb RIPC using a tourniquet resulted in limb paralysis. Hindlimb RIPC using direct clamping of the femoral vessels showed no side effects. Compared to liver IR alone, RIPC+IR reduced plasma aminotransferases (P < 0.05) and histopathological and ultrastructural features of injury. Hepatic microcirculatory blood flow was preserved in the RIPC+IR compared to IR group (P < 0.05). There was no mortality in any of the groups. By demonstrating a consistent improvement in these features of liver IR injury with antecedent hindlimb RIPC and by minimizing experimental confounding variables, we validated this mouse model. In conclusion, we describe a validated mouse model of hindlimb RIPC that reduces liver IR injury. With the availability of transgenic mice strains, this model should prove useful in unraveling the mechanisms of protection of hindlimb RIPC.


Assuntos
Precondicionamento Isquêmico , Fígado/irrigação sanguínea , Músculo Esquelético/irrigação sanguínea , Traumatismo por Reperfusão/prevenção & controle , Alanina Transaminase/sangue , Animais , Aspartato Aminotransferases/sangue , Biomarcadores/sangue , Constrição , Modelos Animais de Doenças , Membro Posterior , Precondicionamento Isquêmico/efeitos adversos , Fluxometria por Laser-Doppler , Fígado/enzimologia , Fígado/ultraestrutura , Circulação Hepática , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microcirculação , Microscopia Eletrônica de Transmissão , Paralisia/etiologia , Traumatismo por Reperfusão/sangue , Traumatismo por Reperfusão/patologia , Reprodutibilidade dos Testes , Fatores de Tempo , Torniquetes
13.
Clin Sci (Lond) ; 121(6): 257-66, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21463257

RESUMO

NO (nitric oxide) may protect the liver from IR (ischaemia/reperfusion) injury. RIPC (remote ischaemic preconditioning) also protects against liver IR injury; however, the molecular mediator(s) of RIPC are currently unknown. The aim of the present study was to assess the role of NO in hindlimb RIPC-induced protection against liver IR injury. Mice were allocated to the following groups: sham group; RIPC group (six cycles of 4×4 min IR of hindlimb); IR group [40 min lobar (70%) hepatic ischaemia and 2-h reperfusion]; RIPC+IR group (RIPC followed by IR group procedures); and C-PTIO [2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide potassium salt]+RIPC+IR group [C-PTIO (a direct NO scavenger) was administered, followed by the RIPC+IR group procedure]. Hepatic MBF (microcirculatory blood flow) was measured throughout the experiment. Circulating NOx (nitrite and nitrate) levels, plasma liver transaminases, hepatic histopathological and TEM (transmission electron microscopy) studies were performed at the end of the experiment. NOx concentrations were significantly elevated (P<0.05) in the RIPC and RIPC+IR groups. Compared with liver IR alone, RIPC+IR preserved hepatic MBF during liver reperfusion (P<0.05). In contrast, C-PTIO+RIPC+IR reduced MBF compared with RIPC+IR (P<0.05). RIPC+IR reduced plasma transaminases (P<0.05), and histopathological and ultrastructural features of injury compared with IR alone. The protective effects of RIPC+IR in reducing liver IR injury were abrogated in the group that received antecedent C-PTIO (C-PTIO+RIPC+IR). In conclusion, NO is an essential mediator of the protection afforded by hindlimb RIPC against liver IR injury. The mechanisms underlying this protection involve preservation of the sinusoidal structure and maintenance of blood flow through the hepatic microcirculation.


Assuntos
Precondicionamento Isquêmico/métodos , Fígado/irrigação sanguínea , Óxido Nítrico/fisiologia , Traumatismo por Reperfusão/prevenção & controle , Animais , Benzoatos/farmacologia , Membro Posterior/irrigação sanguínea , Imidazóis/farmacologia , Fígado/ultraestrutura , Circulação Hepática/efeitos dos fármacos , Circulação Hepática/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microcirculação/efeitos dos fármacos , Microcirculação/fisiologia , Microscopia Eletrônica , Óxido Nítrico/sangue , Traumatismo por Reperfusão/sangue , Traumatismo por Reperfusão/patologia , Traumatismo por Reperfusão/fisiopatologia , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Transaminases/sangue
14.
Biotechnol Appl Biochem ; 58(5): 288-300, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21995532

RESUMO

Repairing nerve defects with large gaps remains one of the most operative challenges for surgeons. Incomplete recovery from peripheral nerve injuries can produce a diversity of negative outcomes, including numbness, impairment of sensory or motor function, possibility of developing chronic pain, and devastating permanent disability. In the last few years, numerous microsurgical techniques, such as coaptation, nerve autograft, and different biological or polymeric nerve conduits, have been developed to reconstruct a long segment of damaged peripheral nerve. A few of these techniques are promising and have become popular among surgeons. Advancements in the field of tissue engineering have led to development of synthetic nerve conduits as an alternative for the nerve autograft technique, which is the current practice to bridge nerve defects with gaps larger than 30 mm. However, to date, despite significant progress in this field, no material has been found to be an ideal alternative to the nerve autograft. This article briefly reviews major up-to-date published studies using different materials as an alternative to the nerve autograft to bridge peripheral nerve gaps in an attempt to assess their ability to support and enhance nerve regeneration and their prospective drawbacks, and also highlights the promising hope for nerve regeneration with the next generation of nerve conduits, which has been significantly enhanced with the tissue engineering approach, especially with the aid of nanotechnology in development of the three-dimensional scaffold. The goal is to determine potential alternatives for nerve regeneration and repair that are simply and directly applicable in clinical conditions.


Assuntos
Engenharia Celular/métodos , Regeneração Nervosa , Nervos Periféricos/fisiologia , Medicina Regenerativa/métodos , Animais , Regeneração Tecidual Guiada/métodos , Humanos , Nanotecnologia/métodos
15.
Lab Invest ; 90(3): 391-401, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20084055

RESUMO

Oxidative stress has an important role in the pathogenesis of many muscle diseases. The major contributors to oxidative stress in muscle tissue are reactive oxygen species such as oxygen ions, free radicals, and peroxides. Insulin-like growth factor I (IGF-I) has been shown to increase muscle mass and promote muscle cell proliferation, differentiation, and survival. We, therefore, hypothesized that IGF-I might also be cytoprotective for muscle cells during oxidative stress. Exogenous hydrogen peroxide (H(2)O(2)) was used to induce oxidative stress/damage in two types of skeletal muscle cells. Apoptotic pathways were assessed after the oxidative damage and the effects of IGF-I on oxidative stress in muscle cells were examined. Different IGF-I sub-pathways were analyzed with measurement of the expression of pro-and anti-apoptotic proteins. It was found that H(2)O(2) diminishes muscle cell viability and induces a caspase-independent apoptotic cell death. Pretreatment with IGF-I protects muscle cells from H(2)O(2)-induced cell death and enhances muscle cells survival. This effect appears to result from the promotion of the anti-apoptotic protein, Bcl2. Further investigation shows that protection is via an IGF-I sub-pathway: PI3K/Akt and ERK1/2 MAPK pathways. Protecting muscle cells from oxidative damage presents a potential application in the treatment of the muscle wasting, which appears in many muscle pathologies including Duchenne muscle dystrophy and sarcopenia.


Assuntos
Fator de Crescimento Insulin-Like I/farmacologia , Sistema de Sinalização das MAP Quinases , Fibras Musculares Esqueléticas/metabolismo , Estresse Oxidativo , Animais , Apoptose , Linhagem Celular , Sobrevivência Celular , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Peróxido de Hidrogênio , Camundongos , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Ratos , Proteínas Recombinantes/farmacologia , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
16.
Liver Transpl ; 16(9): 1016-32, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20818739

RESUMO

Liver ischemia/reperfusion (IR) injury is typified by an inflammatory response. Understanding the cellular and molecular events underpinning this inflammation is fundamental to developing therapeutic strategies. Great strides have been made in this respect recently. Liver IR involves a complex web of interactions between the various cellular and humoral contributors to the inflammatory response. Kupffer cells, CD4+ lymphocytes, neutrophils, and hepatocytes are central cellular players. Various cytokines, chemokines, and complement proteins form the communication system between the cellular components. The contribution of the danger-associated molecular patterns and pattern recognition receptors to the pathophysiology of liver IR injury are slowly being elucidated. Our knowledge on the role of mitochondria in generating reactive oxygen and nitrogen species, in contributing to ionic disturbances, and in initiating the mitochondrial permeability transition with subsequent cellular death in liver IR injury is continuously being expanded. Here, we discuss recent findings pertaining to the aforementioned factors of liver IR, and we highlight areas with gaps in our knowledge, necessitating further research.


Assuntos
Mediadores da Inflamação/metabolismo , Hepatopatias/imunologia , Fígado/imunologia , Traumatismo por Reperfusão/imunologia , Transdução de Sinais , Animais , Humanos , Imunidade Celular , Imunidade Humoral , Fígado/metabolismo , Fígado/patologia , Hepatopatias/metabolismo , Hepatopatias/patologia , Potencial da Membrana Mitocondrial , Mitocôndrias Hepáticas/metabolismo , Espécies Reativas de Nitrogênio/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/patologia
17.
Trends Mol Med ; 15(5): 225-33, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19362056

RESUMO

Colorectal cancer (CRC) is characterized by the partial suppression of apoptosis, which in turn gives tumours a selective advantage for survival and can cause current chemotherapy approaches to be ineffective. Recent progress in understanding the mechanisms of apoptosis in colorectal carcinogenesis has provided potential new targets for therapy. Here, we review recent studies of the regulation of apoptosis and its role in CRC initiation and progression, and we discuss the relationship between chemoresistance and the suppression of apoptosis. Recent progress in targeting apoptotic pathways and their regulators provide strategies for the exploration of novel therapies for CRC.


Assuntos
Apoptose , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Animais , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Proteínas Reguladoras de Apoptose/metabolismo , Neoplasias Colorretais/tratamento farmacológico , Progressão da Doença , Resistencia a Medicamentos Antineoplásicos , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Transdução de Sinais/efeitos dos fármacos
18.
Amyotroph Lateral Scler ; 11(1-2): 172-7, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-19572220

RESUMO

In an animal model of ALS, intramuscular administration of MGF, the IGF-I Ec gene splice variant, improved muscle strength and increased both motor unit and motor neuron survival. Here we investigated whether there is a deficit in MGF production in the muscles of patients with ALS. We used complementary in vivo and in vitro techniques to study the IGF-I splice variant response of human muscle to exercise or mechanical stretch. We assessed the levels of MGF and IGF-IEa mRNA in muscle biopsy samples from healthy subjects and patients with ALS, before and after exercise. We used primary muscle cells to build three-dimensional collagen constructs and subjected them to a ramp stretch. Patients with ALS had similar baseline levels of MGF and IGF-IEa mRNA to healthy controls. No up-regulation was seen in either group within a short time of a single bout of low intensity exercise. Three-dimensional human muscle constructs also detected no response to a mechanical stretch from either control subjects or ALS. We conclude that the pathology of ALS does not include a deficit in baseline levels of MGF and IGF-IEa mRNA splice variants in muscle.


Assuntos
Processamento Alternativo/genética , Esclerose Lateral Amiotrófica/genética , Esclerose Lateral Amiotrófica/fisiopatologia , Fator de Crescimento Insulin-Like I/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Esclerose Lateral Amiotrófica/patologia , Biópsia , Exercício Físico/fisiologia , Feminino , Humanos , Técnicas In Vitro , Masculino , Pessoa de Meia-Idade , Neurônios Motores/patologia , Neurônios Motores/fisiologia , Músculo Esquelético/patologia , Músculo Esquelético/fisiologia , Mioblastos/patologia , Mioblastos/fisiologia , Peptídeos/genética , RNA Mensageiro/genética , Adulto Jovem
19.
Zhonghua Nan Ke Xue ; 16(8): 732-4, 2010 Aug.
Artigo em Zh | MEDLINE | ID: mdl-21090351

RESUMO

OBJECTIVE: To uplift the level in the early diagnosis and treatment of testicular torsion with atypical symptoms. METHODS: Retrospective analysis of 7 cases testicular torsion with atypical symptoms and review of the related literature were performed. RESULTS: Seven patients of testicular torsion came to the emergency department with back pain, among which 5 cases were received the detorsion successfully and 1 case underwent orchiectomy operation. The other patient given up surgery because of his family and himself refused to. CONCLUSION: The attending doctor must firstly check the testicles when the patient complained of back pain as the first symptom, so as to avoid misdiagnosis. As soon as testicular torsion was suspected, urgent surgical exploration should be performed immediately.


Assuntos
Torção do Cordão Espermático/diagnóstico , Adolescente , Adulto , Diagnóstico Precoce , Humanos , Masculino , Estudos Retrospectivos
20.
J Cancer Res Clin Oncol ; 146(11): 2861-2870, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32772171

RESUMO

PURPOSE: IGF-1Ec is an isoform of Insulin-like growth factor 1 (IGF-1) and has recently been identified to be overexpressed in cancers including prostate and neuroendocrine tumours. The aim of this paper is to investigate the expression of IGF-1Ec in colorectal cancer and polyps compared to normal colon tissues and its association with recurrent disease using semi-quantitative immunohistochemistry. METHODS: Immunohistochemistry for IGF-1Ec expression was performed for colorectal cancer, colorectal polyps and normal colonic tissues. The quantification of IGF-1Ec expression was performed with the use of Image J software and the IHC profiler plugin. Following ethics approval from the National Research Ethics Service (Reference 11/LO/1521), clinical information including recurrent disease on follow-up was collected for patients with colorectal cancer. RESULTS: Immunohistochemistry was performed in 16 patients with colorectal cancer and 11 patients with colonic polyps and compared to normal colon tissues and prostate adenocarcinoma (positive control) tissues. Significantly increased expression of IGF-1Ec was demonstrated in colorectal cancer (p < 0.001) and colorectal polyps (p < 0.05) compared to normal colonic tissues. Colonic adenomas with high-grade dysplasia had significantly higher expression of IGF-1Ec compared to low-grade dysplastic adenomas (p < 0.001). Colorectal cancers without lymph node metastases at the time of presentation had significantly higher IGF-1Ec expression compared to lymph node-positive disease (p < 0.05). No correlation with recurrent disease was identified with IGF-1Ec expression. CONCLUSION: IGF-1Ec is significantly overexpressed in colorectal cancer and polyps compared to normal colon tissues offering a potential target to improve colonoscopic identification of colorectal polyps and cancer and intraoperative identification of colorectal tumours.


Assuntos
Pólipos Adenomatosos/diagnóstico , Pólipos do Colo/diagnóstico , Neoplasias Colorretais/diagnóstico , Fator de Crescimento Insulin-Like I/metabolismo , Pólipos Adenomatosos/metabolismo , Pólipos Adenomatosos/patologia , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/análise , Pólipos do Colo/metabolismo , Pólipos do Colo/patologia , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Feminino , Humanos , Imuno-Histoquímica/métodos , Fator de Crescimento Insulin-Like I/análise , Masculino
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