RESUMO
In recent years, research has been conducted to develop new medical treatments by simulating environments existing in space, such as zero-gravity. In this study, we evaluated the cell proliferation and gene expression of activated primary human hepatic stellate cells (HHSteCs) under simulated microgravity (SMG). Under SMG, cell proliferation was slower than in 1 G, and the evaluation of gene expression changes on day 1 of SMG by serial analysis of gene expression revealed the presence of Sirtuin, EIF2 signaling, hippo signaling, and epithelial adherence junction signaling. Moreover, reactive oxygen species were upregulated under SMG, and when N-acetyl-cystein was added, no difference in proliferation between SMG and 1 G was observed, suggesting that the oxidative stress generated by mitochondrial dysfunction caused a decrease in proliferation. Upstream regulators such as smad3, NFkB, and FN were activated, and cell-permeable inhibitors such as Ly294002 and U0126 were inhibited. Immunohistochemistry performed to evaluate cytoskeletal changes showed that more ß-actin was localized in the cortical layer under SMG.
Assuntos
Ausência de Peso , Proliferação de Células , Células Estreladas do Fígado , Humanos , Simulação de Ausência de PesoRESUMO
BACKGROUND: Aspiculuris tetraptera, as a parasitic pinworm, is most frequently detected in laboratory mice, and transmission is mediated by the eggs contained in the faeces of infected mice. A highly sensitive and quantitative faeces-based diagnostic tool would be useful for the early detection of A. tetraptera to inhibit the expansion of infection. In this study, we developed a quantitative assay that exhibits high sensitivity in detecting A. tetraptera in faeces using PCR techniques. RESULTS: Endpoint PCR demonstrated the detection of A. tetraptera DNA in 0.5 ng genomic DNA extracted from the faeces of infected mice. To quantitatively detect the small amount of A. tetraptera DNA, locked nucleic acid (LNA)-based primers and LNA-based TaqMan probes were used for the quantitative PCR assay (qPCR). The combination of LNA-based DNA increased detection sensitivity by more than 100-fold compared to using normal oligo DNAs. The copy number of the A. tetraptera DNA detected was positively related to the infected faeces-derived genomic DNA with a simple linearity regression in the range of 20 pg to 15 ng of the genomic DNA. To more conveniently detect infection using faeces, the LNA-based TaqMan assay was applied to the crude fraction of the faeces without DNA purification. An assay using ethanol precipitation of the faeces yielded results consistent with those of direct microscopic observation. CONCLUSION: The LNA-TaqMan assay developed in this study quantitatively detects A. tetraptera infection in mouse faeces.
Assuntos
DNA de Helmintos/análise , Fezes/parasitologia , Oxyuroidea/isolamento & purificação , Carga Parasitária/normas , Animais , Primers do DNA , DNA de Helmintos/genética , Camundongos , Oligonucleotídeos , Oxyuroidea/genética , Carga Parasitária/métodos , Reação em Cadeia da Polimerase em Tempo Real , Padrões de ReferênciaRESUMO
BACKGROUND/AIMS: We have developed a mixed-cell sheet consisting of autologous fibroblasts and peripheral blood mononuclear cells with a high potency for angiogenesis and wound healing against refractory cutaneous ulcers in mouse and rabbit models. To increase the effectiveness of the mixed sheet, we developed a multilayered mixed sheet. METHODS: We assessed the therapeutic effects of multilayered sheets on cutaneous ulcers in mice. Growth factors and chemokines were assessed by enzyme-linked immunosorbent assay. Angiogenesis and fibroblast migration were measured by using tube formation and migration assays. Wound healing rate of cutaneous ulcers was evaluated in mice with diabetes mellitus. RESULTS: The concentration of secreted vascular endothelial growth factor, hepatocyte growth factor, transforming growth factor, C-X-C motif chemokine ligand (CXCL)-1, and CXCL-2 in multilayered sheets was much higher than that in single-layered mixed-cell sheets (single-layered sheets) and multilayered sheets of fibroblasts alone (fibroblast sheets). The supernatant in multilayered sheets enhanced angiogenic potency and fibroblast migration compared with single-layered and fibroblast sheets in an in vitro experiment. The wound healing rate in the multilayered sheet-treated group was higher compared with the no-treatment group (control) at the early stage of healing. Moreover, both vessel lumen area and microvessel density in tissues treated with multilayered sheets were significantly increased compared with tissues in the control group. CONCLUSION: Multilayered sheets promoted wound healing and microvascular angiogenesis in the skin by supplying growth factors and cytokines. Accordingly, our data suggest that multilayered sheets may be a promising therapeutic material for refractory cutaneous ulcers.
Assuntos
Fibroblastos/transplante , Leucócitos Mononucleares/transplante , Neovascularização Fisiológica , Úlcera/terapia , Cicatrização , Animais , Movimento Celular , Células Cultivadas , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Pele/patologia , Úlcera/patologiaRESUMO
Here we describe a Japanese patient with mild ß-thalassemia (ß-thal) with an intact ß-globin gene but a new missense mutation of c.947G > A or p.C316Y in the erythroid Krüppel-Like Factor (KLF1) gene which is strongly associated with the expression of the ß-globin gene. The association of the KLF1 mutation with ß-thal, is here described. The p.C316Y mutation occurred at one of the cysteines that constitute the second zinc finger motif of KLF1, and would have changed the zinc finger conformation to impair the DNA binding properties or the promoter function of the ß-globin gene. Our expression study found that the mutant KLF1 gene had a markedly negative effect on the ß-globin gene expression, or 7.0% of that of its normal counterpart. A presumed heterozygous state, or equimolar presence of the mutant and normal KLF1s reduced the expression rate to 70.0% of the normal alone. This degree of the decrease may explain the very mild phenotype of the patient's ß-thal. Furthermore, the patient's whole-exome analysis using next-generation sequencing revealed that the ß-thal defect is caused by only this KLF1 gene mutation. The Hb A2 and Hb F levels that are frequently elevated in KLF1 mutations were elevated by 4.1 and 1.3%, respectively, in this case. The contribution to their elevation by KLF1: p.C316Y is uncertain.
Assuntos
Fatores de Transcrição Kruppel-Like/genética , Mutação , Talassemia beta/diagnóstico , Talassemia beta/genética , Adulto , Sequência de Aminoácidos , Povo Asiático/genética , Códon , DNA Complementar/química , DNA Complementar/genética , Exoma , Expressão Gênica , Ordem dos Genes , Genes Reporter , Loci Gênicos , Heterozigoto , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Japão , Fatores de Transcrição Kruppel-Like/química , Masculino , Mutação de Sentido Incorreto , Fenótipo , Regiões Promotoras Genéticas , Dedos de Zinco/genéticaRESUMO
BACKGROUND: Hypoxic preconditioning of bone marrow cells (BMCs) from young healthy individuals can enhance the cells' therapeutic potential. Considering that the response to hypoxia may differ according to the quality of the cells, we assessed the effect of hypoxic preconditioning on BMCs from aged mice and compared the difference in response between BMCs from aged and young mice. METHODS AND RESULTS: BMCs from young (3 months) and aged (20-22 months) mice were subjected to hypoxic preconditioning by culture for 24 h in 2% O2. Compared with BMCs from young mice, those from aged mice showed significantly fewer CD34- or c-kit-positive stem cells, higher expression of p53, and lower telomerase activity. Adhesion, survival and angiogenic potency were also lower in BMCs from aged mice, indicating an aging-related impairment. Hypoxia-preconditioned BMCs from aged mice showed enhanced adhesion, survival, and angiogenic potency with the in vitro assessments, as well as the in vivo implantation into ischemic hindlimbs. All the enhancements by hypoxic preconditioning were comparable between BMCs from aged and young mice, although the angiogenic potential of BMCs with and without hypoxic preconditioning was lower in old mice compared with young mice. CONCLUSIONS: Similar responses to hypoxia by BMCs from both aged and young mice suggest that hypoxic preconditioning could be a useful method of enhancing the angiogenic potential of BMCs.
Assuntos
Envelhecimento/metabolismo , Células da Medula Óssea/metabolismo , Células Endoteliais/metabolismo , Neovascularização Fisiológica , Fatores Etários , Animais , Antígenos CD34/metabolismo , Transplante de Medula Óssea , Adesão Celular , Hipóxia Celular , Sobrevivência Celular , Células Cultivadas , Modelos Animais de Doenças , Células Endoteliais/transplante , Membro Posterior , Isquemia/metabolismo , Isquemia/fisiopatologia , Isquemia/cirurgia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Músculo Esquelético/irrigação sanguínea , Estresse Oxidativo , Proteínas Proto-Oncogênicas c-kit/metabolismo , Telomerase/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismoRESUMO
The purpose of this study was to investigate the therapeutic effect of cryopreserved allogenic fibroblast cell sheets in a mouse model of skin ulcers. It is necessary to reduce the cost of regenerative medicine for it to be widely used. We consider that cell sheets could be applied to various diseases if cryopreservation of allogenic cell sheets was possible. In this study, fibroblasts were frozen using a three-dimensional freezer. Freeze-thawed fibroblasts had ~80% cell viability, secreted ≥ 50% vascular endothelial growth factor, hepatocyte growth factor, and stromal derived factor-1α compared with non-frozen fibroblast sheets, and secreted approximately the same amount of transforming growth factor-ß1. There was no difference in wound-healing rates in the skin ulcer model between non-frozen and freeze-thawed fibroblast sheets regardless of autologous and allogenic cells. The degree of angiogenesis was comparable between autologous and allogenic cells. The number of CD3-positive cells in healed tissues was larger for allogenic fibroblast sheets compared with autologous fibroblast sheets. However, histopathological images showed that the fibrosis, microvascular density, and healing phase of the wound in allogenic freeze-thawed fibroblast sheets were more similar to autologous freeze-thawed fibroblast sheets than to allogenic non-frozen fibroblast sheets. These results suggest that allogenic freeze-thawed fibroblast sheets may be a promising therapeutic option for refractory skin ulcers.
RESUMO
Nucleobases are important compounds that constitute nucleosides and nucleic acids. Although it has long been suggested that specific transporters are involved in their intestinal absorption and uptake in other tissues, none of their molecular entities have been identified in mammals to date. Here we describe identification of rat Slc23a4 as the first sodium-dependent nucleobase transporter (rSNBT1). The mRNA of rSNBT1 was expressed highly and only in the small intestine. When transiently expressed in HEK293 cells, rSNBT1 could transport uracil most efficiently. The transport of uracil mediated by rSNBT1 was sodium-dependent and saturable with a Michaelis constant of 21.2 microM. Thymine, guanine, hypoxanthine, and xanthine were also transported, but adenine was not. It was also suggested by studies of the inhibitory effect on rSNBT1-mediated uracil transport that several nucleobase analogs such as 5-fluorouracil are recognized by rSNBT1, but cytosine and nucleosides are not or only poorly recognized. Furthermore, rSNBT1 fused with green fluorescent protein was mainly localized at the apical membrane, when stably expressed in polarized Madin-Darby canine kidney II cells. These characteristics of rSNBT1 were almost fully in agreement with those of the carrier-mediated transport system involved in intestinal uracil uptake. Therefore, it is likely that rSNBT1 is its molecular entity or at least in part responsible for that. It was also found that the gene orthologous to the rSNBT1 gene is genetically defective in humans. This may have a biological and evolutional meaning in the transport and metabolism of nucleobases. The present study provides novel insights into the specific transport and metabolism of nucleobases and their analogs for therapeutic use.
Assuntos
Absorção Intestinal , Proteínas de Transporte de Nucleobases/metabolismo , Purinas/metabolismo , Pirimidinas/metabolismo , Animais , Linhagem Celular , Cães , Humanos , Cinética , Dados de Sequência Molecular , Ratos , Sódio , Especificidade da Espécie , Especificidade por Substrato , Uracila/metabolismoRESUMO
The importance of TNF-α signals mediated by tumor necrosis factor receptor type 1 (TNFR1) in inflammation and fibrosis induced by carbon tetrachloride (CCl(4)), and in post-injury liver regeneration including a GFP/CCl(4) model developed as a liver repair model by bone marrow cell (BMC) infusion, was investigated. In mice in which TNFR1 was suppressed by antagonist administration or by knockout, liver fibrosis induced by CCl(4) was significantly decreased. In these mice, intrahepatic macrophage infiltration and TGF-ß1 expression were reduced and stellate cell activity was decreased; however, expression of MMP-9 was also decreased. With GFP-positive BMC (TNFR1 wild-type, WT) infusion in these mice, fibrosis proliferation, including host endogenous intrahepatic macrophage infiltration, TGF-ß1 expression and stellate cell activity, increased significantly. There was no significant increase of MMP-9 expression. In this study, TNFR1 in hosts had a promoting effect on CCl(4)-induced hepatotoxicity and fibrosis, whereas BMC infusion in TNFR1 knockout mice enhanced host-derived intrahepatic inflammation and fibrosis proliferation. These findings differed from those in WT recipient mice, in which improvement in inflammation and fibrosis with BMC infusion had previously been reported. TNFR1-mediated signaling might be important to induce the improvement of liver fibrosis by bone marrow cell infusion.
Assuntos
Células da Medula Óssea/metabolismo , Transplante de Medula Óssea , Cirrose Hepática/metabolismo , Cirrose Hepática/terapia , Receptores Tipo I de Fatores de Necrose Tumoral/metabolismo , Transdução de Sinais , Animais , Células da Medula Óssea/patologia , Tetracloreto de Carbono/toxicidade , Intoxicação por Tetracloreto de Carbono/genética , Intoxicação por Tetracloreto de Carbono/metabolismo , Intoxicação por Tetracloreto de Carbono/patologia , Cirrose Hepática/induzido quimicamente , Cirrose Hepática/genética , Cirrose Hepática/patologia , Macrófagos/metabolismo , Macrófagos/patologia , Metaloproteinase 9 da Matriz/metabolismo , Camundongos , Camundongos Knockout , Receptores Tipo I de Fatores de Necrose Tumoral/genética , Fator de Crescimento Transformador beta1/genética , Fator de Crescimento Transformador beta1/metabolismo , Transplante HomólogoRESUMO
AIM: To investigate the maternal risk factors for small-for-gestational age (SGA) newborns in Japanese dichorionic (DC) twins. METHODS: A retrospective study was conducted from 2003 to 2008 on 340 DC twin pregnancies resulting in two live births. Newborns were classified as SGA if their birth weight was below the 10th percentile according to Japanese singleton norms. Statistical differences were evaluated between pregnancies resulting in appropriate-for-gestational age (AGA) pairs and those resulting in at least one SGA neonate. RESULTS: The study population consisted of AGA/AGA (50.8%), AGA/SGA (37.0%) and SGA/SGA pairs (12.0%). Logistic regression analysis identified significant interrelations for SGA with maternal nulliparity (odds ratio [OR] 0.52, 95% confidence interval [CI] 0.30-0.91), smoking (OR 3.25, 95% CI 1.09-9.66), assisted reproductive technology (OR 0.52, 95% CI 0.30-0.89), pregnancy-induced hypertension (OR 2.00, 95% CI 1.01-4.31), pregravid weight (kg) (unitary OR 0.94, 95% CI 0.91-0.97) and monthly weight gain (kg/month) (unitary OR 0.25, 95% CI 0.14-0.44). Bivariable receiver operating characteristic curves were generated for monthly weight gain (area under the curve [AUC] 0.626, cutoff 1.41 kg/month, P<0.001) and total weight gain (AUC 0.615, cutoff 14.0 kg, P<0.001). CONCLUSION: Cigarette smoking and weight gain control are relatively modifiable factors for which interventional management is necessary to avoid perinatal problems arising from SGA pregnancy. Further studies are needed to investigate optimal nutrition, health guidance and subsequent weight gain control that lead to concrete improvement in maternal and infant prognoses.
Assuntos
Retardo do Crescimento Fetal/etiologia , Recém-Nascido Pequeno para a Idade Gestacional , Gêmeos , Feminino , Retardo do Crescimento Fetal/epidemiologia , Humanos , Recém-Nascido , Japão/epidemiologia , Gravidez , Estudos Retrospectivos , Fatores de RiscoRESUMO
Riboflavin transporter (RFT) 2 has recently been identified as a transporter that may be, mainly based on the functional characteristics of its rat ortholog (rRFT2), involved in the intestinal absorption of riboflavin. The present study was conducted to further examine such a possible role of RFT2, focusing on the functional characteristics of its human ortholog (hRFT2) and the response of rRFT2 expression in the small intestine to deprivation of dietary riboflavin. When transiently expressed in human embryonic kidney 293 cells, hRFT2 could transport riboflavin efficiently in a pH-sensitive manner, favoring acidic pH and without requiring Na(+). Riboflavin transport by hRFT2 was saturable with a Michaelis constant of 0.77 µmol/L at pH 6.0, and inhibited by some riboflavin derivatives, such as lumiflavin. It was also inhibited, to a lesser extent, by some cationic compounds, such as ethidium. Thus, hRFT2 was suggested to, together with a finding that its mRNA is highly expressed in the small intestine, have characteristics as an intestinal RFT. Furthermore, feeding rats a riboflavin-deficient diet caused an upregulation of the expression of rRFT2 mRNA in the small intestine, presumably as an adaptive response to enhance riboflavin absorption, which would involve rRFT2, and its apically localized characteristic was suggested by the observation of rRFT2 tagged with green fluorescent protein stably expressed in polarized Madin-Darby canine kidney II cells. All these results combined indicate that RFT2 is a transporter involved in the epithelial uptake of riboflavin in the small intestine for its nutritional utilization.
Assuntos
Expressão Gênica/efeitos dos fármacos , Intestino Delgado/química , Proteínas de Membrana Transportadoras/genética , Proteínas de Membrana Transportadoras/fisiologia , Riboflavina/farmacologia , Animais , Linhagem Celular , Proteínas de Ligação a DNA , Dieta , Cães , Embrião de Mamíferos , Etídio/farmacologia , Proteínas de Fluorescência Verde/genética , Humanos , Concentração de Íons de Hidrogênio , Absorção Intestinal/fisiologia , Rim , Masculino , Azul de Metileno/farmacologia , RNA Mensageiro/análise , Ratos , Ratos Wistar , Receptores Acoplados a Proteínas G , Proteínas Recombinantes de Fusão/genética , Riboflavina/administração & dosagem , Riboflavina/metabolismo , Deficiência de Riboflavina/metabolismo , Fatores de TranscriçãoRESUMO
We have previously shown that infusion of bone marrow cells (BMC) improves CCl(4)-induced cirrhosis. However, it is unclear why the injected BMC are resistant to CCl(4) damage and subsequently improve the local microenvironment in damaged liver. To analyze the cellular phenomena involved in this process, we studied the damaged liver using electron microscopy. We found that CCl(4) caused rough endoplasmic reticula to swell in hepatocytes. To analyze the gene expression patterns associated with this process, we conducted PCR-selected suppressive subtractive hybridization. We found that expression levels of HSP84, HSP40, and XBP1 differed markedly between control liver and liver infused with BMC. Immunohistochemical staining revealed that expression levels of HSP84 and HSP40 were markedly higher in the early phase of differentiation immediately after BMC infusion, but decreased over time. XBP1 expression remained high during the late phase, and GRP78 expression increased with XBP1 activation. We also found that GFP-positive BMC expressed XBP1 and GRP78. XBP1 and GRP78 are associated with ER stress. Thus, continuous high XBP1 and GRP78 expression might be essential for the survival and proliferation of BMC in a CCl(4)-induced persistent liver damage environment.
Assuntos
Células da Medula Óssea/metabolismo , Tetracloreto de Carbono , Proteínas de Ligação a DNA/biossíntese , Proteínas de Choque Térmico/biossíntese , Cirrose Hepática Experimental/metabolismo , Chaperonas Moleculares/biossíntese , Proteínas Nucleares/biossíntese , Animais , Western Blotting , Células da Medula Óssea/citologia , Transplante de Medula Óssea , Diferenciação Celular/efeitos dos fármacos , Sobrevivência Celular , Sistema Enzimático do Citocromo P-450/metabolismo , Proteínas de Ligação a DNA/genética , Modelos Animais de Doenças , Progressão da Doença , Chaperona BiP do Retículo Endoplasmático , Feminino , Expressão Gênica/efeitos dos fármacos , Perfilação da Expressão Gênica , Proteínas de Choque Térmico HSP40/biossíntese , Proteínas de Choque Térmico HSP90/biossíntese , Proteínas de Choque Térmico/genética , Imuno-Histoquímica , Cirrose Hepática Experimental/induzido quimicamente , Cirrose Hepática Experimental/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Microscopia Eletrônica , Chaperonas Moleculares/genética , Proteínas Nucleares/genética , Fatores de Transcrição de Fator Regulador X , Fatores de Transcrição , Proteína 1 de Ligação a X-BoxRESUMO
BACKGROUND/AIMS: To elucidate the pathogenesis of hepatic encephalopathy (HE), we developed a new HE model with behaviour disorder. METHODS: Male Wistar rats were divided into four treatment groups: a HE model: acetaminophen (APAP)+3-methylcholanthrene (3-MC) group (APAP+MC group); control group: acetaminophen group; 3-methylcholanthrene group; and a no-treatment group. We monitored the changes of neural amino acids in the synaptic cleft and astrocytes in the brain during behaviour disorder. RESULTS: In the APAP+MC group, alanine amino transferase, blood ammonia and glucose increased from 3 h and total bilirubin increased at 6 h. Prothrombin time was prolonged from 3 h in the APAP+MC group. The APAP+MC group exhibited centrilobular necrosis in the liver after 8 h. In the APAP+MC group, rats jumped vertically and this vertical activity increased significantly from 4 to 7 h. During the behaviour disorder, we found that glutamate and aspartate increased in the synaptic cleft from 4 h after treatment with APAP+3-MC, glutamate increased 23.9-fold at 7 h and aspartate increased 16.1-fold at 4 h, whereas glutamine did not change. At that time, we observed morphological changes of the astrocytes by immunostaining for the glial fibrillary acidic protein. CONCLUSIONS: Our new HE model demonstrated that increased excitatory neural amino acids and morphological change in astrocytes were involved in the behaviour disorder that occurs with HE.
Assuntos
Aminoácidos/metabolismo , Astrócitos/metabolismo , Encéfalo/metabolismo , Modelos Animais de Doenças , Encefalopatia Hepática/metabolismo , Encefalopatia Hepática/patologia , Acetaminofen/toxicidade , Animais , Western Blotting , Estimulação Elétrica , Encefalopatia Hepática/induzido quimicamente , Imuno-Histoquímica , Masculino , Metilcolantreno/toxicidade , Desempenho Psicomotor/efeitos dos fármacos , Ratos , Ratos WistarRESUMO
Sodium-dependent nucleobase transporter 1 (SNBT1) is a nucleobase-specific transporter identified in our recent study. In an attempt to search for its potential substrates other than nucleobases in this study, we could successfully find urate, a metabolic derivative of purine nucleobases, as a novel substrate, as indicated by its specific Na+ -dependent and saturable transport, with a Michaelis constant of 433 µmol/L, by rat SNBT1 (rSNBT1) stably expressed in Madin-Darby canine kidney II cells. However, urate uptake was observed only barely in the everted tissue sacs of the rat small intestine, in which rSNBT1 operates for nucleobase uptake. These findings suggested that urate undergoes a futile cycle, in which urate transported into epithelial cells is immediately effluxed back by urate efflux transporters, in the small intestine. In subsequent attempts to examine that possibility, such a futile urate cycle was demonstrated in the human embryonic kidney 293 cell line as a model cell system, where urate uptake induced by transiently introduced rSNBT1 was extensively reduced by the co-introduction of rat breast cancer resistance protein (rBCRP), a urate efflux transporter present in the small intestine. However, urate uptake was not raised in the presence of Ko143, a BCRP inhibitor, in the everted intestinal tissue sacs, suggesting that some other transporter might also be involved in urate efflux. The newly found urate transport function of SNBT1, together with the suggested futile urate cycle in the small intestine, should be of interest for its evolutional and biological implications, although SNBT1 is genetically deficient in humans.
Assuntos
Proteínas de Transporte de Nucleobases/metabolismo , Ácido Úrico/metabolismo , Animais , Transporte Biológico , Cães , Células HEK293 , Humanos , Intestino Delgado/metabolismo , Células Madin Darby de Rim Canino , Masculino , Ratos WistarRESUMO
OBJECTIVE: We examined the relation between first-trimester crown-rump length (CRL) discordance and birth weight discordance in dichorionic twin pregnancies conceived by assisted reproductive technology (ART). METHODS: We examined 101 nulliparous dichorionic twin pregnancies producing male-male or female-female infants conceived spontaneously (n = 38) or following in vitro fertilization and embryo transfer (n = 63). RESULTS: There were no significant differences in CRL disparity or birth weight discordance between spontaneous and ART-conceived dichorionic twin pregnancies. There was a positive correlation between CRL disparity and birth weight discordance in ART-conceived twin pregnancies (r(2) = 0.22, p = 0.02), while there was no such correlation in spontaneous pregnancies (r(2) = 0.02, p = 0.40). CONCLUSION: In ART-conceived dichorionic twin pregnancies, CRL disparity may be associated with birth weight discordance.
Assuntos
Estatura Cabeça-Cóccix , Desenvolvimento Fetal/fisiologia , Técnicas de Reprodução Assistida , Gêmeos/fisiologia , Adulto , Peso ao Nascer/fisiologia , Feminino , Humanos , Masculino , Gravidez , Técnicas de Reprodução Assistida/efeitos adversosRESUMO
Companion animal spontaneous tumors are suitable models for human cancer, primarily because both animal population and the tumors are genetically heterogeneous. Feline mammary carcinoma (FMC) is a highly aggressive, mainly hormone receptor-negative cancer, which has been proposed as a model for poor prognosis human breast cancer. We have identified and studied the feline orthologue of the HER2 gene, which is both an important prognostic marker and therapeutic target in human cancer. Feline HER2 (f-HER2) gene kinase domain is 92% similar to the human HER2 kinase. F-HER2-specific mRNA was found 3- to 18-fold increased in 3 of 3 FMC cell lines, in 1 of 4 mammary adenomas and 6 of 11 FMC samples using quantitative reverse transcription-PCR. Western blot showed that an anti-human HER2 antibody recognized a protein comigrating with the human p185HER2 in FMC cell lines. The same antibodies strongly stained 13 of 36 FMC archival samples. These data show that feline HER2 overexpression qualifies FMC as homologous to the subset of HER2 overexpressing, poor prognosis human breast carcinomas and as a suitable model to test innovative approaches to therapy of aggressive tumors.
Assuntos
Neoplasias da Mama/genética , Neoplasias da Mama/veterinária , Genes erbB-2/genética , Receptor ErbB-2/biossíntese , Animais , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Gatos , Linhagem Celular Tumoral , Modelos Animais de Doenças , Feminino , Humanos , Imuno-Histoquímica , Glândulas Mamárias Animais/metabolismo , Prognóstico , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Receptor ErbB-2/genética , Reação em Cadeia da Polimerase Via Transcriptase ReversaRESUMO
We developed a novel mouse model of human refractory cutaneous ulcers that more faithfully reflects pathology and evaluated the effects of mixed cell sheets comprising peripheral blood mononuclear cells and fibroblasts, which we previously developed for treating refractory cutaneous ulcers. Model development involved sandwiching the skin between two magnets, one of which was implanted under the skin for 7 consecutive days. This magnet-implanted ulcer model produced persistently large amounts of exudate and induced the infiltration of the ulcer with inflammatory cells. The model mice had a thicker epidermis and impaired transforming growth factor-ß (TGF-ß) signaling followed by SMAD2 down-regulation, which causes epidermal hyperplasia in chronic ulcers. Impaired TGF-ß signaling also occurred in the ulcers of critical limb ischemia patients. Mixed cell implantation in this ulcer model reduced TNF-α and IL-6 levels in the tissues surrounding the mixed cell sheet-treated ulcers compared with controls or mice treated with trafermin (FGF2). Seven days after commencing therapy, the epidermis was thinner in mice treated with the mixed cell sheets than in controls. This model may therefore serve as a clinically relevant model of human ulcers, and our mixed cell sheets may effectively relieve chronic inflammation and inhibit refractoriness mechanisms.
Assuntos
Modelos Animais de Doenças , Imãs , Úlcera Cutânea/patologia , Úlcera Cutânea/fisiopatologia , Animais , Histocitoquímica , Camundongos , Transdução de Sinais , Proteína Smad2/metabolismo , Fator de Crescimento Transformador beta/metabolismoRESUMO
We developed mixed cell sheets consisting of fibroblasts and peripheral blood mononuclear cells that had high potency for secreting vascular endothelial growth factor. The purpose of this study was to confirm the therapeutic effects of mixed sheets in rabbits suffering from ulcers at the ischemic hind limbs. We used the ulcer model, which was constructed by implantation and sandwiching the skin between two magnets to be a representative of human refractory cutaneous ulcer. The ulcer healing rate of mixed cell sheets was higher than that of the control at an early stage of healing. The calf blood pressure and angiographic score, which were considered to reflect rough collateral blood flow, did not vary amongmixed cell sheets. However, through laser Doppler perfusion image, implantation of mixed cell sheets revealed a significant improvement in microvascular blood flow in the healed skin of the ischemic limb compared to trafermin, a recombinant human basic fibroblast growth factor, and the control. These results suggest that mixed cell may operate predominantly on the surface of the ischemic tissue by their angiogenic potency, thereby promoting healing of the ischemic ulcer. Mixed cell sheets could become a promising therapeutic material for refractory cutaneous ulcers.
RESUMO
BACKGROUND: Recent studies have shown that bone marrow-derived stem cells differentiate into the phenotype of cardiomyocytes in vivo and in vitro. We tried to regenerate infarcted myocardium by implanting ex vivo transforming growth factor (TGF)-beta-preprogrammed CD117 (c-kit)-positive (CD117+) stem cells intramyocardially. METHODS AND RESULTS: CD117+ cells were isolated from the bone marrow mononuclear cells of GFP-transgenic or normal C57/BL6 mice. The myogenic differentiation of CD117+ cells was achieved by cultivation with TGF-beta. Using an acute myocardial infarction model, we also tried to regenerate infarcted myocardium by implanting untreated (newly isolated) or preprogrammed (24 hours of cultivation with 5 ng/mL TGF-beta1) CD117+ cells intramyocardially. TGF-beta increased the cellular expression of myosin, troponins, connexin-43, GATA-4, and NKx-2.5, which suggested that it induced the myogenic differentiation of CD117+ cells. Compared with the effects of PBS injection only, the microvessel density in the infarcted myocardium was increased significantly 3 months after the implantation of either TGF-beta-preprogrammed or untreated CD117+ cells. Moreover, many of the TGF-beta-preprogrammed CD117+ cells were stained positively for myosin, whereas few of the untreated CD117+ cells were. Histological analysis revealed newly regenerated myocardium in the left ventricular anterior wall after the implantation of TGF-beta-preprogrammed cells but not untreated cells. Furthermore, the left ventricular percent fraction shortening was significantly higher after the implantation of TGF-beta-preprogrammed cells than after the implantation of untreated CD117+ cells. CONCLUSIONS: TGF-beta conducted the myogenic differentiation of CD117+ stem cells by upregulating GATA-4 and NKx-2.5 expression. Therefore, the intramyocardial implantation of TGF-beta-preprogrammed CD117+ cells effectively assisted the myocardial regeneration and induced therapeutic angiogenesis, contributing to functional cardiac regeneration.
Assuntos
Transplante de Células-Tronco Hematopoéticas , Células-Tronco Hematopoéticas/efeitos dos fármacos , Infarto do Miocárdio/patologia , Infarto do Miocárdio/terapia , Miócitos Cardíacos/citologia , Regeneração/efeitos dos fármacos , Fator de Crescimento Transformador beta/farmacologia , Animais , Células da Medula Óssea , Técnicas de Cultura de Células , Diferenciação Celular , Fator de Transcrição GATA4/genética , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/metabolismo , Proteína Homeobox Nkx-2.5 , Proteínas de Homeodomínio/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Neovascularização Fisiológica/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-kit , Fatores de Transcrição/genética , Regulação para Cima/efeitos dos fármacosRESUMO
The purpose of this study was to confirm the therapeutic effects of mixed sheets consisting of peripheral blood mononuclear cells (PBMNCs) and fibroblasts on cutaneous skin ulcers. Vascular endothelial growth factor (VEGF) secretion in mixed cell sheets was much higher than in PBMNCs and fibroblasts. Concerning the mechanism, transforming growth factor beta 1 and platelet-derived growth factor BB secreted from PBMNCs enhanced VEGF production in fibroblasts. In wounds created on the backs of diabetic mice, the therapeutic effect of mixed cell sheets was similar to that of daily treatment with trafermin, a recombinant human basic fibroblast growth factor. Although abnormal granulation tissue and inflammatory cell infiltration were observed in trafermin-treated wounds, the transplantation of mixed cell sheets resulted in the natural anatomy of subcutaneous tissues. The expression patterns of identical wound-healing factors in wounds were different between mixed sheet-transfected and trafermin-treated animals. Because mixed cell sheets transplanted into full-thickness skin defects were eliminated in hosts by day 21 in syngeneic transplantation models, allogeneic transplantation was performed using mice with different genetic backgrounds. The wound-healing rates were similar between the mixed cell sheet and trafermin groups. Our data indicated that mixed cell sheets represent a promising therapeutic material for cutaneous ulcers.
Assuntos
Fibroblastos/transplante , Leucócitos Mononucleares/transplante , Úlcera Cutânea/terapia , Animais , Becaplermina , Complicações do Diabetes/metabolismo , Complicações do Diabetes/patologia , Complicações do Diabetes/terapia , Diabetes Mellitus Experimental/complicações , Modelos Animais de Doenças , Feminino , Fatores de Crescimento de Fibroblastos/uso terapêutico , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C3H , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Fragmentos de Peptídeos/uso terapêutico , Proteínas Proto-Oncogênicas c-sis/biossíntese , Transplante de Pele , Úlcera Cutânea/metabolismo , Úlcera Cutânea/patologia , Pele Artificial , Fator de Crescimento Transformador beta1/biossíntese , Transplante Homólogo , Fator A de Crescimento do Endotélio Vascular/biossíntese , Fator A de Crescimento do Endotélio Vascular/genética , Cicatrização , Cromossomo Y/genéticaRESUMO
Complementary DNA (cDNA) for bovine quaking gene (Bqk), equine quaking gene (Eqk) and porcine quaking gene (Pqk), which are homologous to mouse quaking gene (qkI), were isolated, and their nucleotide sequences were determined. cDNA sequences of Bqk, Eqk and Pqk showed very high homology to that of qkI at nucleotide level; 94.2, 95.7 and 95.6%, respectively. Deduced amino acid sequences for Bqk, Eqk and Pqk perfectly matched to that of qkI. These findings suggest that the quaking gene family is highly conserved during mammalian evolution, and that Bqk, Eqk and Pqk are likely to have important biological functions also in cow, horse and pig.