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1.
Neuropathol Appl Neurobiol ; 46(4): 391-405, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-31630421

RESUMO

AIMS: Investigations of the molecular mechanisms of hypoxia- and ischaemia-induced endogenous neural progenitor cell (NPC) proliferation have mainly focused on factors secreted in response to environmental cues. However, little is known about the intrinsic regulatory machinery underlying the self-renewing division of NPCs in the brain after stroke. METHODS AND RESULTS: Polycomb repressor complex 1-chromobox7 (CBX7) has emerged as a key regulator in several cellular processes including stem cell self-renewal and cancer cell proliferation. The hypoxic environment triggering NPC self-renewal after CBX7 activation remains unknown. In this study, we found that the upregulation of CBX7 during hypoxia and ischaemia appeared to be from hypoxia-inducible factor-1α (HIF-1α) activation. During hypoxia, the HIF-1α-CBX7 cascade modulated NPC proliferation in vitro. NPC numbers significantly decreased in CBX7 knockout mice generated using CRISPR/Cas9 genome editing. CONCLUSIONS: We provided the novel insight that CBX7 expression is regulated through HIF-1α activation, which plays an intrinsically modulating role in NPC proliferation.


Assuntos
Regulação da Expressão Gênica/fisiologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Hipóxia-Isquemia Encefálica/metabolismo , Células-Tronco Neurais/metabolismo , Complexo Repressor Polycomb 1/metabolismo , Animais , Hipóxia Celular/fisiologia , Proliferação de Células/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Ratos
2.
Pediatr Transplant ; 22(2)2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29334158

RESUMO

The liver's capacity to grow in response to metabolic need is well known. However, long-term growth of liver allografts in pediatric recipients has not been characterized. A retrospective review of pediatric recipients at a single institution identified patients who had cross-sectional imaging at 1, 5, and 10 years post-transplant. Using volumetric calculations, liver allograft size was calculated and percent SLV were compared across the different time points; 18 patients ranging from 0.3 to 17.7 years old were identified that had imaging at 2 or more time points. Measured liver volumes increased by 59% after 5 years and 170% after 10 years. The measured liver volumes compared to calculated %SLV for these patients were 123 ± 37%, 97 ± 19%, and 118 ± 27% at 1, 5, and 10 years after transplant, respectively. Our data suggest that liver allografts in pediatric recipients increase along with overall growth, and reach SLVs for height and weight by 5 years post-transplantation. Additionally, as pediatric recipients grow, the livers appear to maintain appropriate SLV.


Assuntos
Aloenxertos/crescimento & desenvolvimento , Transplante de Fígado , Fígado/crescimento & desenvolvimento , Adolescente , Aloenxertos/diagnóstico por imagem , Criança , Pré-Escolar , Feminino , Seguimentos , Humanos , Lactente , Recém-Nascido , Fígado/diagnóstico por imagem , Imageamento por Ressonância Magnética , Masculino , Tamanho do Órgão , Avaliação de Resultados em Cuidados de Saúde , Estudos Retrospectivos , Tomografia Computadorizada por Raios X , Transplante Homólogo
3.
Microb Ecol ; 70(1): 168-74, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25592636

RESUMO

Formation of magnetite in anaerobic sediments is thought to be enhanced by the activities of iron-reducing bacteria. Geobacter has been implicated as playing a major role, as in culture its cells are often associated with extracellular magnetite grains. We studied the bacterial community associated with magnetite grains in sediment of a freshwater pond in South Korea. Magnetite was isolated from the sediment using a magnet. The magnetite-depleted fraction of sediment was also taken for comparison. DNA was extracted from each set of samples, followed by PCR for 16S bacterial ribosomal RNA (rRNA) gene and HiSeq sequencing. The bacterial communities of the magnetite-enriched and magnetite-depleted fractions were significantly different. The enrichment of three abundant operational taxonomic units (OTUs) suggests that they may either be dependent upon the magnetite grain environment or may be playing a role in magnetite formation. The most abundant OTU in magnetite-enriched fractions was Geobacter, bolstering the case that this genus is important in magnetite formation in natural systems. Other major OTUs strongly associated with the magnetite-enriched fraction, rather than the magnetite-depleted fraction, include a Sulfuricella and a novel member of the Betaproteobacteria. The existence of distinct bacterial communities associated with particular mineral grain types may also be an example of niche separation and coexistence in sediments and soils, which cannot usually be detected due to difficulties in separating and concentrating minerals.


Assuntos
Óxido Ferroso-Férrico/análise , Sedimentos Geológicos/microbiologia , Microbiota/genética , Lagoas/microbiologia , Sequência de Bases , Primers do DNA/genética , Geobacter/genética , Sedimentos Geológicos/química , Dados de Sequência Molecular , RNA Ribossômico 16S/genética , Reação em Cadeia da Polimerase em Tempo Real , República da Coreia , Análise de Sequência de DNA , Especificidade da Espécie
4.
Acta Physiol (Oxf) ; 213(1): 222-31, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25287331

RESUMO

One of the frequent clinical complications that results in billions of dollars in healthcare costs annually in the United States is acute kidney injury (AKI). Ischaemia reperfusion (IR) injury is a major cause AKI. Unfortunately, no effective treatment or preventive measure for AKI exists. With increased surgical complexity coupled with increasing number of elderly, the incidence of AKI is becoming more frequent. Adenosine is a metabolic breakdown product of adenosine triphosphate (ATP) and contributes to the regulation of multiple physiological events. Extracellular adenosine activates four subtypes of adenosine receptors (AR) including A1 AR, A2 A AR, A2 B AR and A3 AR. In the kidney, adenosine regulates glomerular filtration rate, vascular tone, renin release and is an integrative part of tubular glomerular feedback signal to the afferent arterioles. In addition, each AR subtype powerfully modulates renal IR injury. The A1 AR activation protects against ischaemic insult by reducing apoptosis, necrosis and inflammation. Activation of A2 A AR protects against renal injury by modulating leucocyte-mediated inflammation as well as directly reducing renal tubular inflammation. Activation of A2 B AR acts via direct activation of renal parenchymal as well as renovascular receptors and is important in kidney preconditioning. Finally, activation of A3 AR exacerbates renal damage following renal IR injury while A3 AR antagonism attenuates renal damage following ischaemic insult. Latest body of research suggests that kidney AR modulation may be a promising approach to treat ischaemic AKI. This brief review focuses on the signalling pathways of adenosine in the kidney followed by the role for various AR modulations in protecting against ischaemic AKI.


Assuntos
Apoptose/fisiologia , Nefropatias/metabolismo , Receptores Purinérgicos P1/metabolismo , Traumatismo por Reperfusão/metabolismo , Animais , Humanos , Necrose/metabolismo
5.
J Phys Condens Matter ; 26(39): 395402, 2014 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-25204391

RESUMO

Employing a thermodynamic model with previously calculated first-principle energetics as inputs, we determined the hydrogen (H) concentration at the interstitial and monovacancy as well as its dependence on temperature and pressure in tungsten and molybdenum. Based on this, we predicted the critical H concentration for H bubble formation at different temperatures. The critical concentration, defined as the value when the concentration of H at a certain mH-vacancy complex first became equal to that of H at the interstitial, was 24 ppm/7.3 GPa and 410 ppm/4.7 GPa at 600 K in tungsten and molybdenum in the case of a monovacancy. Beyond the critical H concentration, numerous H atoms accumulated in the monovacancy, leading to the formation and rapid growth of H-vacancy complexes, which was considered the preliminary stage of H bubble formation. We expect that the proposed approach will be generally used to determine the critical H concentration for H bubble formation in metals.

6.
Clin Exp Immunol ; 176(1): 66-77, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24345202

RESUMO

We measured plasma levels of the oxidative DNA damage marker 8-hydroxy-2'-deoxyguanosine (8-OHdG) and leucocyte mRNA expression levels of the genes encoding the 8-OHdG repair enzyme human 8-oxoguanine DNA glycosylase 1 (hOGG1), the anti-oxidant enzymes copper/zinc superoxide dismutase (Cu/ZnSOD), manganese superoxide dismutase (MnSOD), catalase, glutathione peroxidase-1 (GPx-1), GPx-4, glutathione reductase (GR) and glutathione synthetase (GS), the mitochondrial biogenesis-related proteins mtDNA-encoded ND 1 polypeptide (ND1), ND6, ATPase 6, mitochondrial transcription factor A (Tfam), nuclear respiratory factor 1(NRF-1), pyruvate dehydrogenase E1 component alpha subunit (PDHA1), pyruvate dehydrogenase kinase isoenzyme 1 (PDK-1) and hypoxia inducible factor-1α (HIF-1α) and the glycolytic enzymes hexokinase-II (HK-II), glucose 6-phosphate isomerase (GPI), phosphofructokinase (PFK), glyceraldehyde 3-phosphate dehydrogenase (GAPDH) and lactate dehydrogenase A (LDHa). We analysed their relevance to oxidative damage in 85 systemic lupus erythematosus (SLE) patients, four complicated SLE patients undergoing rituximab treatment and 45 healthy individuals. SLE patients had higher plasma 8-OHdG levels (P < 0·01) but lower leucocyte expression of the genes encoding hOGG1(P < 0·01), anti-oxidant enzymes (P < 0·05), mitochondrial biogenesis-related proteins (P < 0·05) and glycolytic enzymes (P < 0·05) than healthy individuals. The increase in plasma 8-OHdG was correlated positively with the elevation of leucocyte expression of the genes encoding hOGG1 (P < 0·05), anti-oxidant enzymes (P < 0·05), several mitochondrial biogenesis-related proteins (P < 0·05) and glycolytic enzymes (P < 0·05) in lupus patients. The patients, whose leucocyte mtDNA harboured D310 heteroplasmy, exhibited a positive correlation between the mtDNA copy number and expression of ND1, ND6 and ATPase 6 (P < 0·05) and a negative correlation between mtDNA copy number and systemic lupus erythematosus disease activity index (SLEDAI) (P < 0·05), as well as plasma 8-OHdG (P < 0·05). In particular, four complicated SLE patients with increased expression of the genes encoding the anti-oxidant enzymes, GAPDH, Tfam and PDHA1, experienced better therapeutic outcomes after rituximab therapy. In conclusion, higher oxidative damage with suboptimal increases in DNA repair, anti-oxidant capacity, mitochondrial biogenesis and glucose metabolism may be implicated in SLE deterioration, and this impairment might be improved by targeted biological therapy.


Assuntos
DNA Glicosilases/metabolismo , Desoxiguanosina/análogos & derivados , Leucócitos/metabolismo , Lúpus Eritematoso Sistêmico/metabolismo , Proteínas Mitocondriais/metabolismo , 8-Hidroxi-2'-Desoxiguanosina , Adulto , Anticorpos Monoclonais Murinos/uso terapêutico , Antirreumáticos/uso terapêutico , Dano ao DNA , DNA Glicosilases/genética , Reparo do DNA/genética , DNA Mitocondrial/genética , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Desoxiguanosina/sangue , Feminino , Dosagem de Genes , Regulação Enzimológica da Expressão Gênica , Glutationa Peroxidase/genética , Glutationa Peroxidase/metabolismo , Glicólise/genética , Humanos , Leucócitos/efeitos dos fármacos , Leucócitos/patologia , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Lúpus Eritematoso Sistêmico/genética , Masculino , Pessoa de Meia-Idade , Mitocôndrias/genética , Mitocôndrias/metabolismo , Proteínas Mitocondriais/genética , Estresse Oxidativo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Rituximab , Índice de Gravidade de Doença , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Glutationa Peroxidase GPX1
7.
Acta Physiol (Oxf) ; 210(4): 799-810, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24299003

RESUMO

AIMS: Soluble guanylyl cyclase (sGC) is a key modulator in the regulation of vascular tone. However, its role and involving mechanism in cholesterol metabolism of macrophages and atherosclerosis remain unclear. METHODS: Oil red O staining, Dil-oxidized low-density lipoprotein (oxLDL)-binding assay and cholesterol efflux assay were performed in biology of foam cells. Levels of cytokines or intracellular lipid were evaluated by ELISA or colorimetric kits. Expression of gene or protein was determined by quantitative real-time PCR or Western blotting. Histopathology was examined by haematoxylin and eosin staining. RESULTS: Soluble guanylyl cyclase was expressed in macrophages of mouse atherosclerotic lesions. Treatment with 1H-[1, 2, 4]oxadiazolo[4,3-a]quinoxalin-1-one (ODQ, sGC inhibitor) exacerbated oxLDL-induced cholesterol accumulation in macrophages. In contrast, 3-(5'-hydroxymethyl-2'furyl)-1-benzyl indazole (YC-1, sGC activator) attenuated the oxLDL-induced cholesterol accumulation because of increased cholesterol efflux. Additionally, YC-1 dose dependently increased the protein expression of ATP-binding cassette transporter A1 (ABCA1) but did not alter that of scavenger receptor class A (SR-A), CD36, SR-BI or ABCG1. Moreover, YC-1-upregulated ABCA1 level depended on liver X receptor α (LXRα). Inhibition of the LXRα-ABCA1 pathway by LXRα small interfering RNA (siRNA), ABCA1 neutralizing antibody or ABCA1 siRNA abolished the effect of YC-1 on cholesterol accumulation and cholesterol efflux. In vivo, YC-1 retarded the development of atherosclerosis, accompanied by reduced serum levels of cholesterol and pro-inflammatory cytokines, in apolipoprotein E-deficient mice. CONCLUSION: Activation of sGC by YC-1 leads to LXRα-dependent upregulation of ABCA1 in macrophages and may confer protection against atherosclerosis.


Assuntos
Aterosclerose/metabolismo , Ativação Enzimática/fisiologia , Células Espumosas/fisiologia , Guanilato Ciclase/metabolismo , Transportador 1 de Cassete de Ligação de ATP/genética , Transportador 1 de Cassete de Ligação de ATP/metabolismo , Animais , Apolipoproteínas E/genética , Apolipoproteínas E/metabolismo , Linhagem Celular , Células Espumosas/citologia , Guanilato Ciclase/genética , Indazóis/farmacologia , Metabolismo dos Lipídeos , Lipoproteínas LDL/metabolismo , Fígado/enzimologia , Receptores X do Fígado , Macrófagos/enzimologia , Macrófagos/metabolismo , Camundongos , Camundongos Knockout , Miocárdio/enzimologia , Receptores Nucleares Órfãos/genética , Receptores Nucleares Órfãos/metabolismo
8.
Asian-Australas J Anim Sci ; 26(4): 588-95, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25049827

RESUMO

Mesenchymal stem cells (MSCs) are often known to have a therapeutic potential in the cell-mediated repair for fatal or incurable diseases. In this study, canine umbilical cord MSCs (cUC-MSCs) were isolated from umbilical cord matrix (n = 3) and subjected to proliferative culture for 5 consecutive passages. The cells at each passage were characterized for multipotent MSC properties such as proliferation kinetics, expression patterns of MSC surface markers and self-renewal associated markers, and chondrogenic differentiation. In results, the proliferation of the cells as determined by the cumulative population doubling level was observed at its peak on passage 3 and stopped after passage 5, whereas cell doubling time dramatically increased after passage 4. Expression of MSC surface markers (CD44, CD54, CD61, CD80, CD90 and Flk-1), molecule (HMGA2) and pluripotent markers (sox2, nanog) associated with self-renewal was negatively correlated with the number of passages. However, MSC surface marker (CD105) and pluripotent marker (Oct3/4) decreased with increasing the number of subpassage. cUC-MSCs at passage 1 to 5 underwent chondrogenesis under specific culture conditions, but percentage of chondrogenic differentiation decreased with increasing the number of subpassage. Collectively, the present study suggested that sequential subpassage could affect multipotent properties of cUC-MSCs and needs to be addressed before clinical applications.

9.
Res Vet Sci ; 94(1): 144-51, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22975229

RESUMO

Multipotent mesenchymal stem cells have been considered as a novel clinical approach for cell therapy and regenerative medicine. In this study, mesenchymal stem cells (MSCs) were successfully isolated from canine umbilical cord matrix (cUCM; also referred to as Wharton's Jelly) by collagenase digestion and further characterized for multipotent properties associated with MSCs. Our cUCM-derived MSCs (cUCM-MSCs) were plastic adherent, spindle-shaped and fibroblast-like cells, maintaining expression of pluripotency markers such as Oct3/4, Nanog, Sox-2 and SSEA-4 as well as normal chromosomal number during a long-term proliferative culture. The cells expressed MSCs-specific surface markers, including CD44, CD90, CD105, and CD184, but did not CD29, CD33, CD34, and CD45. More importantly, cUCM-MSCs could differentiate into mesodermal (adipocyte, osteocyte and chondrocyte) and ectodermal (neuronal cell) cell lineages. These results imply that collagenase digestion would be a highly effective way to isolate multipotent MSCs in abundant amounts.


Assuntos
Células-Tronco Mesenquimais/citologia , Cordão Umbilical/citologia , Animais , Diferenciação Celular/fisiologia , Colagenases , Corantes , Cães , Citometria de Fluxo/veterinária , Imunofluorescência/veterinária , Perfilação da Expressão Gênica/veterinária , Técnicas In Vitro , Cariotipagem/veterinária , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Mesenquimais/fisiologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa/veterinária
10.
Theriogenology ; 78(5): 1085-93, 2012 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-22763071

RESUMO

Cryopreservation of bovine embryos can be performed by a variety of methods with variable degree of success. Here, we report a new, easy to perform, simple, inexpensive, and successful method for vitrification of bovine blastocysts. In vitro produced bovine blastocysts were exposed to vitrification solution (5.5 m ethylene glycol, 10% serum and 1% sucrose) in one single step for 20 s, loaded on a paper container prepared from commonly available non-slippery, absorbent writing paper, and then were directly plunged into liquid nitrogen for storage. Vitrified blastocysts were warmed by serial rinsing in 0.5, 0.25 and 0.125 m sucrose solution for 1 min each. Results showed that one step exposure of bovine blastocysts to cryoprotective agents was sufficient to achieve successful cryopreservation. Under these conditions, more than 95% of blastocysts survived the vitrification-warming on paper containers which was significantly higher than those obtained from other containers, such as electron microscope (EM) grid (78.1%), open pulled straw (OPS; 80.2%), cryoloop (76.2%) or plastic straw (73.9%). Embryo transfer of blastocysts vitrified-warmed on paper container resulted in successful conception (19.3%) and full-term live birth of offspring (12.3%) which were lower (P < 0.05) than those obtained from non-vitrified blastocysts (38.0 and 32.7%) but were comparable (P > 0.05) to those obtained from blastocysts vitrified-warmed on EM grid (23.3 and 14.2%). Our results, therefore, suggest that paper may be an inexpensive and useful container for the cryopreservation of animal embryos.


Assuntos
Blastocisto/fisiologia , Bovinos/embriologia , Criopreservação/veterinária , Animais , Bovinos/fisiologia , Técnicas de Cultura Embrionária , Feminino , Fertilização in vitro , Técnicas de Maturação in Vitro de Oócitos , Papel , Gravidez
11.
Lett Appl Microbiol ; 54(4): 306-12, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22268495

RESUMO

AIMS: For the analysis of virulence factors produced and secreted by Bacillus anthracis vegetative cells during mammalian host infection, we evaluated the secretome of B. anthracis Sterne exposed to host-specific factors specifically to host body temperature. METHODS AND RESULTS: We employed a comparative proteomics-based approach to analyse the proteins secreted by B. anthracis Sterne under host-specific body temperature conditions. A total of 17 proteins encoded on a single chromosome and the pXO1 plasmid were identified by peptide mass fingerprinting. Multiple algorithms were used to predict the secretion mechanisms of the detected proteins in B. anthracis. CONCLUSIONS: Several putative virulence factors and known factors responsible for sporulation were differentially regulated, including CodY, pXO1-130 and BA1952, revealing insights into temperature cues in the B. anthracis secretome. SIGNIFICANCE AND IMPACT OF THE STUDY: This study identified temperature-regulated proteins. Further studies aimed at understanding the physical and functional roles of these proteins in infection and control by elevated temperatures will contribute to detection, diagnostics and prophylaxis.


Assuntos
Antraz/microbiologia , Bacillus anthracis/fisiologia , Bacillus anthracis/patogenicidade , Proteínas de Bactérias/análise , Fatores de Virulência/análise , Bacillus anthracis/classificação , Bacillus anthracis/genética , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Temperatura Corporal , Humanos , Proteômica , Virulência , Fatores de Virulência/genética , Fatores de Virulência/metabolismo
12.
Poult Sci ; 89(12): 2660-7, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21076105

RESUMO

Fatty liver hemorrhagic syndrome (FLHS) is characterized by increased hepatic triacylglycerol content associated with liver hemorrhages and results in a sudden decline in egg production. Genetic, environmental, nutritional, and hormonal factors have all been implicated in the etiology of FLHS, but the exact cause of FLHS is still unknown. Estrogens have been implicated in the development of excess fat content of the liver and in the etiology of FLHS. This study investigated estradiol (E(2)) administration in hens and its effect on lipid metabolism. Hy-Line Brown laying hens were intramuscularly injected with E(2) on a daily basis for 3 wk. The dosages were 0, 0.5, and 1.0 mg/kg of BW, with corn oil injections used as a control. Egg production and quality were measured among the groups, with no significant difference seen in egg production. Liver weights of hens treated with E(2) were greater than those of control hens, but the increase was not statistically significant. Serum glutamic-oxaloacetic transaminase and glutamic-pyruvic transaminase activities and E(2) plasma concentrations increased in a dose-dependent manner, with plasma concentration of E(2) increasing from 6,900 to 19,000 pg/mL. No significant differences in free cholesterol or phospholipids were observed, but there was a significant increase in hepatic triacylglycerol levels. Injection with E(2) showed an increased expression of mRNA for peroxisome proliferator-activated receptor γ (23-fold), but not for peroxisome proliferator-activated receptor α. A statistically significant increase was seen for fatty acid synthase, apolipoprotein B, and adenosine triphosphate citrate lyase, but not for acetyl coenzyme A carboxylase, apolipoprotein VLDL-II, microsomal triglyceride transport protein, or malic enzyme. For proteins involved in the oxidation of E(2), only cytochrome P450 3A37 showed a statistically significant increase. The present results suggest that E(2) upregulates the synthesis of fatty acids and triacylglycerols and the accumulation of hepatic lipids by increasing mRNA expression related to lipid metabolism, and that excess E(2) in the blood leads to activation of E(2) catabolic metabolism (cytochrome P450 3A37)-related mRNA expression.


Assuntos
Galinhas/fisiologia , Estradiol/farmacologia , Fígado Gorduroso/veterinária , Metabolismo dos Lipídeos/fisiologia , Fígado/metabolismo , Oviposição/fisiologia , RNA Mensageiro/genética , Animais , Fígado Gorduroso/metabolismo , Feminino , Metabolismo dos Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Oviposição/efeitos dos fármacos , Receptores Ativados por Proliferador de Peroxissomo/metabolismo , Doenças das Aves Domésticas/metabolismo , RNA Mensageiro/efeitos dos fármacos , Vitaminas/administração & dosagem
13.
Tissue Antigens ; 76(4): 301-10, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20604896

RESUMO

To enable the efficient analysis of a highly polymorphic swine major histocompatibility complex (MHC) class II gene, swine leukocyte antigen (SLA)-DQB1, we developed a simple and comprehensive high-resolution genotyping protocol. To obtain sufficient sequence information to design a set of common genotyping primers for SLA-DQB1, we cloned SLA-DQB1 introns 1 and 2 from 11 alleles with official four-digit allelic designations and sequenced the regions directly surrounding the SLA-DQB1 exon 2. Significant intronic nucleotide variations, including several deletions, were identified. Based on 733-bp assembled genomic sequences including introns 1 and 2 and exon 2 from 11 different alleles, a primer set was identified that allowed the ubiquitous amplification and analysis of the complete SLA-DQB1 exon 2 sequence. We then developed a method to directly sequence the amplified polymerase chain reaction (PCR) products without further experimental steps. We especially focused on avoiding superimposed peaks, which arose from the presence of allelic deletions, in the sequencing electropherogram of SLA-DQB1 heterozygous animals. The genotyping accuracy was evaluated by comparing the results of genomic sequence-based typing (GSBT) with those of other available methods, including cDNA sequence-based typing (SBT), low-resolution PCR typing with sequence-specific primers, allelic segregation analysis, and heterozygote simulation typing. In all cases, the results were consistent between SLA-DQB1 GSBT and previously reported methods or expected results. We applied it to genotype 350 animals from seven pig breeds. The observed level of heterozygosity from our genotyping was ∼51%, reflecting that a large portion of the animals were inbred miniature pigs. Among the seven pig breeds tested, the allelic diversity of SLA-DQB1 was highest in Berkshire pigs. In conclusion, we have developed a simple and effective SLA-DQB1 GSBT method by combining simple genomic DNA PCR and direct sequencing. Our new method may aid in the study of SLA diversity and disease resistance and susceptibility.


Assuntos
Antígenos HLA-DQ/genética , Antígenos de Histocompatibilidade Classe II/genética , Reação em Cadeia da Polimerase/veterinária , Análise de Sequência de DNA/veterinária , Suínos , Animais , Sequência de Bases , Primers do DNA , Variação Genética , Genótipo , Cadeias beta de HLA-DQ , Antígenos de Histocompatibilidade Classe I , Dados de Sequência Molecular , Reprodutibilidade dos Testes , Alinhamento de Sequência , Suínos/genética
14.
Theriogenology ; 73(8): 1024-36, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20106515

RESUMO

Epidermal growth factor (EGF) has been considered a potential regulator of meiotic and cytoplasmic maturation in mammalian oocytes, but inconsistencies exist between earlier studies, probably due to differences in the culture conditions used. Using a serum- and hormone-free in vitro maturation (IVM) medium, this study investigated the specific contribution of EGF on IVM of porcine (Sus scrofa) oocytes and its interactive effects with follicle-stimulating hormone (FSH), porcine follicular fluid (pFF), cumulus cells, and serum. It was noteworthy that EGF functionally mimicked the action of FSH and could completely replace FSH for nuclear maturation (83.2+/-4.4% vs. 55.9+/-5.2%; mean+/-SEM), whereas EGF had a synergistic effect with FSH on cytoplasmic maturation of porcine oocytes (P<0.05). Specific inhibition of EGF receptor (EGFR) by tyrphostin AG 1478 inhibited both EGF- and FSH-induced meiotic resumption (17.9+/-5.2% and 18.2+/-4.4%, respectively), thereby suggesting that EGFR signaling pathway was essential for oocyte reentry into the meiotic cell cycle. Furthermore, it is possible that FSH action occurs via the EGFR signaling pathway to induce meiotic maturation, although alternate pathways could not be excluded. There were also individual or combined effects of cumulus cells, FSH, serum, and pFF with EGF on IVM of porcine oocytes (P<0.05). Although FSH had a synergistic effect with EGF on cytoplasmic maturation, pFF masked the effects of EGF on both nuclear and cytoplasmic maturation of porcine oocytes (P<0.05). Moreover, the presence of cumulus cells was essential for EGF action. In conclusion, a defined system was used to better examine the effects of EGF. We inferred that EGF functionally mimics FSH for nuclear maturation of porcine oocytes, and its exogenous supplementation into IVM medium can optimize the beneficial effects of FSH on cytoplasmic maturation of oocytes to obtain enhanced embryo development in vitro.


Assuntos
Núcleo Celular/efeitos dos fármacos , Fator de Crescimento Epidérmico/farmacologia , Hormônio Foliculoestimulante/farmacologia , Oócitos/efeitos dos fármacos , Suínos , Animais , Células Cultivadas , Interações Medicamentosas , Técnicas de Cultura Embrionária , Embrião de Mamíferos/citologia , Embrião de Mamíferos/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Feminino , Fertilização in vitro/métodos , Fertilização in vitro/veterinária , Oócitos/metabolismo , Oócitos/ultraestrutura , Oogênese/efeitos dos fármacos , Biossíntese de Proteínas/efeitos dos fármacos , Quinazolinas , Suínos/embriologia , Equivalência Terapêutica , Tirfostinas/farmacologia
15.
Neurogastroenterol Motil ; 22(5): e138-51, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20059699

RESUMO

BACKGROUND: Animals carrying genetic mutations have provided powerful insights into the role of interstitial cells of Cajal (ICC) in motility. One classic model is the W/W(V) mouse which carries loss-of-function mutations in c-kit alleles, but retains minimal function of the tyrosine kinase. Previous studies have documented loss of slow waves and aberrant motility in the small intestine of W/W(V) mice where myenteric ICC (ICC-MY) are significantly depleted. METHODS: Here, we used morphological and electrophysiological techniques to further assess the loss of ICC around the circumference of the small intestine and determine consequences of losing ICC-MY on electrical activity, Ca(2+) transients and contractions of the longitudinal muscle (LM). KEY RESULTS: In wild-type mice, there was coherent propagation of Ca(2+) transients through the ICC-MY network and spread of this activity to the LM. In short segments of small intestine in vitro and in exteriorized segments, slow waves coordinated smoothly propagating Ca(2+) waves and contractions in the LM of wild-type mice. In W/W(V) mice, Ca(2+) waves were initiated at variable sites along and around intestinal segments and propagated without constraint unless they collided with other Ca(2+) waves. This activity resulted in abrupt, uncoordinated contractions. CONCLUSIONS & INFERENCES: These results show how dominance of pacemaking by ICC-MY coordinates propagating con-tractions and regulates the spontaneous activity of smooth muscle.


Assuntos
Células Intersticiais de Cajal/fisiologia , Intestino Delgado/fisiologia , Contração Muscular/fisiologia , Músculo Liso/fisiologia , Plexo Mientérico/fisiologia , Potenciais de Ação/fisiologia , Animais , Cálcio/metabolismo , Eletrofisiologia , Feminino , Masculino , Camundongos , Camundongos Transgênicos , Rede Nervosa/fisiologia , Transmissão Sináptica/fisiologia
16.
Neurogastroenterol Motil ; 22(2): 186-95, e64, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19735476

RESUMO

BACKGROUND: Altered calcium mobilization has been implicated in the development of colonic dysmotility in inflammatory bowel disease. The aim of this study was to investigate the mechanisms by which disrupted intracellular Ca(2+) signalling contributes to the impaired contractility of colon circular smooth muscles. METHODS: Acute colitis was induced in C57Bl/6 mice with dextran sulphate sodium (DSS) in the drinking water for 5 days. KEY RESULTS: Spontaneous and acetylcholine-evoked contractions, caffeine-evoked hyperpolarization, and SERCA2 and phospholamban expression were reduced compared with controls. Tetrodotoxin did not restore control levels of contractile activity. The amplitudes, but not the frequency, of intracellular Ca(2+) waves were increased compared with controls. Caffeine abolished intracellular Ca(2+) waves in control smooth muscle cells, but not in smooth muscle cells from DSS-treated mice. CaM kinase II activity and cytosolic levels of HDAC4 were increased, and I kappaB alpha levels were decreased in distal colon smooth muscles from DSS-treated mice. CONCLUSIONS & INFERENCES: These results suggest that disruptions in intracellular Ca(2+) mobilization due to down-regulation of SERCA2 and phospholamban expression lead to increased CaM kinase II activity and cytosolic HDAC4 that may contribute to the dysmotility of colonic smooth muscles in colitis by enhancing NF-kappaB activity.


Assuntos
Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Colite/fisiopatologia , Colo/metabolismo , Motilidade Gastrointestinal/fisiologia , Contração Muscular/fisiologia , Músculo Liso/metabolismo , Acetilcolina/farmacologia , Potenciais de Ação/efeitos dos fármacos , Potenciais de Ação/fisiologia , Animais , Western Blotting , Cafeína/farmacologia , Sinalização do Cálcio/efeitos dos fármacos , Sinalização do Cálcio/fisiologia , Proteínas de Ligação ao Cálcio/metabolismo , Colite/induzido quimicamente , Colite/metabolismo , Colo/efeitos dos fármacos , Colo/fisiopatologia , Sulfato de Dextrana/toxicidade , Regulação para Baixo , Eletrofisiologia , Motilidade Gastrointestinal/efeitos dos fármacos , Masculino , Camundongos , Contração Muscular/efeitos dos fármacos , Músculo Liso/efeitos dos fármacos , Músculo Liso/fisiopatologia , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/metabolismo , Fatores de Tempo
17.
Am J Transplant ; 10(2): 372-81, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19958323

RESUMO

Hypothermic machine perfusion (HMP) is widely used to preserve kidneys for transplantation with improved results over cold storage (CS). To date, successful transplantation of livers preserved with HMP has been reported only in animal models. In this, the first prospective liver HMP study, 20 adults received HMP-preserved livers and were compared to a matched group transplanted with CS livers. HMP was performed for 3-7 h using centrifugal perfusion with Vasosol solution at 4-6 degrees C. There were no cases of primary nonfunction in either group. Early allograft dysfunction rates were 5% in the HMP group versus 25% in controls (p = 0.08). At 12 months, there were two deaths in each group, all unrelated to preservation or graft function. There were no vascular complications in HMP livers. Two biliary complications were observed in HMP livers compared with four in the CS group. Serum injury markers were significantly lower in the HMP group. Mean hospital stay was shorter in the HMP group (10.9 +/- 4.7 days vs. 15.3 +/- 4.9 days in the CS group, p = 0.006). HMP of donor livers provided safe and reliable preservation in this pilot case-controlled series. Further multicenter HMP trials are now warranted.


Assuntos
Transplante de Fígado , Adulto , Criopreservação , Humanos , Hipotermia/fisiopatologia , Fígado/fisiopatologia , Testes de Função Hepática , Perfusão/métodos
18.
Anesthesiol Clin ; 27(4): 739-49, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19942177

RESUMO

Preoperative evaluation of patients with renal dysfunction often requires the collaborative efforts of the primary care physician, nephrologist, surgeon, and anesthesiologist. Renal dysfunction is typically a spectrum of disease with multisystem effects. Optimization of preexisting medical issues is the key, as is a thorough understanding of the potential perioperative risks for further renal injury. Surgical or anesthetic techniques may require alteration for the patient with significant renal dysfunction. Identification of those at risk for renal injury may allow for preventative therapies in the perioperative period. This article focuses on defining the population at risk, a framework for preoperative evaluation, and developments in the area of perioperative renal protection.

19.
Med Clin North Am ; 93(5): 1083-93, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19665621

RESUMO

Preoperative evaluation of patients with renal dysfunction often requires the collaborative efforts of the primary care physician, nephrologist, surgeon, and anesthesiologist. Renal dysfunction is typically a spectrum of disease with multisystem effects. Optimization of preexisting medical issues is the key as is a thorough understanding of the potential perioperative risks for further renal injury. Surgical or anesthetic techniques may require alteration for the patient with significant renal dysfunction. Identification of those at risk for renal injury may allow for preventative therapies in the perioperative period. This article focuses on defining the population at risk, a framework for preoperative evaluation, and developments in the area of perioperative renal protection.


Assuntos
Injúria Renal Aguda/complicações , Falência Renal Crônica/complicações , Assistência Perioperatória/métodos , Injúria Renal Aguda/diagnóstico , Anti-Hipertensivos/efeitos adversos , Taxa de Filtração Glomerular , Humanos , Falência Renal Crônica/diagnóstico
20.
J Anim Breed Genet ; 126(2): 127-33, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19320769

RESUMO

Sequences from the clones of full-length enriched cDNA libraries serve as valuable resources for functional genomic studies. We have analysed 1970 high-quality chromatograms (Phred value >or= 30) that were obtained from sequencing the 5' ends of brainstem, liver, neocortex and spleen clones derived from full-length enriched cDNA libraries from Korean native pigs. In addition, 50,000 pig expressed sequence tag (EST) sequence trace files were obtained from Genbank and combined with our sequencing information to facilitate SNP identification in silico. The process generated 8118 contigs, of which 239 included minimum one sequence from Korean native pig and contained 678 putative coding single nucleotide polymorphisms (cSNPs). Of these, 33 putative cSNPs were randomly selected for confirmatory analysis and validated using 20 pigs from four different breeds (Duroc, Landrace, Yorkshire, Korean native pig). Of the 33 putative cSNPs, 20 were confirmed (61%), which was similar to the frequency reported in other studies. We also identified 15 new cSNPs from the validation process, which were not detected by our in silico analysis. Our study shows that analysing genetically diverse pig breeds including the Korean native pig could serve as a useful strategy for generating a large number of cSNPs.


Assuntos
Polimorfismo de Nucleotídeo Único/genética , Sus scrofa/genética , Animais , Sequência de Bases , Primers do DNA/genética , Biblioteca Gênica , Coreia (Geográfico) , Dados de Sequência Molecular , Análise de Sequência de DNA , Especificidade da Espécie
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