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1.
J Plant Res ; 131(6): 1047-1054, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30066035

RESUMO

The liverwort Marchantia polymorpha has become one of the model organisms, since it has less genetic redundancy, sexual and asexual modes of reproduction and a range of genomic and molecular genetic resources. Cryopreservation of fertile spermatozoa eliminates time, space and labor for growing and maintaining male plants in reproductive phase, and also provides an optional way to backup lines. Here we report a protocol to cryopreserve spermatozoa of M. polymorpha in liquid nitrogen. A cryoprotective solution containing sucrose, glycerol and egg yolk and controlled cooling and warming processes led to successful recovery of motile M. polymorpha spermatozoa after the cryogenic process. The survival rate and average motility of spermatozoa after cryopreservation were maintained at 71 and 54% of those before cryopreservation, respectively. Cryopreserved spermatozoa were capable of fertilization to form normal spores. The technique presented here confers more versatility to experiments using M. polymorpha and could be applied to preservation of plant spermatozoa in general.


Assuntos
Criopreservação/métodos , Marchantia , Pólen , Crioprotetores/uso terapêutico
2.
Hepatol Res ; 36(2): 130-8, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16920400

RESUMO

The asialoglycoprotein receptor (ASGPR) is abundantly expressed on the sinusoidal surfaces of hepatocytes. However, regional expression and clinical significance of the ASGPR in acute hepatic damage is presently unknown. Our aim was to clarify the clinical significance of the regional expression of ASGPR in human livers with acute hepatitis (AH) and fulminant hepatic failure (FHF). Eighteen volunteers, 42 patients with AH and 10 with FHF were studied using a newly developed, conventional (99m)Tc-GSA SPECT analysis. Using Cantlie's line as a guide, ASGPR expression was analyzed separately in the right and left hepatic lobes, as well as in the whole liver, using novel indices (the liver uptake ratio [LUR] and liver uptake density [LUD], which reflect the amount and density of ASGPRs in the liver, respectively). Mean LUR and LUD values for the whole liver and the right and left lobes decreased in accordance with the severity of acute hepatic damage. In the FHF group, the reduction in LUR and LUD values in the right lobes was more significant than in the left lobes. The LUR and LUD values for the whole liver correlated well with hepatic functional reserve and total bilirubin levels. The right LUR and LUD values in particular correlated well with these parameters. A time-course observation of 13 patients with either AH or FHF revealed that the expression of ASGPRs in the right lobe recovered faster than in the left. We first evaluated the regional expression of AGSPRs by (99m)Tc-GSA SPECT analysis in both AH and FHF patients, which is a clinically useful and reliable indicator for assessing the severity of regional hepatic damage and evaluating regional liver regeneration.

4.
Hepatology ; 41(6): 1272-81, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15915457

RESUMO

The proliferation of hepatic stellate cells (HSCs) is a critical step in hepatic fibrogenesis. Platelet-derived growth factor (PDGF) is the most potent mitogen for HSCs. We investigated the role of nonphagocytic NAD(P)H oxidase-derived reactive oxygen species (ROS) in PDGF-induced HSC proliferation. The human HSC line, LI-90 cells, murine primary-cultured HSCs, and PDGF-BB were used in this study. We examined the mechanism of PDGF-BB-induced HSC proliferation in relation to the role of a ROS scavenger and diphenylene iodonium, an inhibitor of NAD(P)H oxidase. We also measured ROS production with the aid of chemiluminescence. We showed that PDGF-BB induced proliferation of HSCs through the intracellular production of ROS. We also demonstrated that HSCs expressed key components of nonphagocytic NAD(P)H oxidase (p22phox, gp91phox, p47phox, and p67phox) at both the messenger RNA and protein levels. Diphenylene iodonium suppressed PDGF-BB-induced ROS production and HSC proliferation. Coincubation of H2O2 and PDGF-BB restored the proliferation of HSCs that was inhibited by diphenylene iodonium pretreatment. Phosphorylation of the mitogen-activated protein kinase (MAPK) family constitutes a signal transduction pathway of cell proliferation. Our data demonstrate that NAD(P)H oxidase-derived ROS induce HSC proliferation mainly through the phosphorylation of p38 MAPK. Moreover, an in vivo hepatic fibrosis model also supported the critical role of NAD(P)H oxidase in the activation and proliferation of HSCs. In conclusion, NAD(P)H oxidase is expressed in HSCs and produces ROS via activation of NAD(P)H oxidase in response to PDGF-BB. ROS further induce HSC proliferation through the phosphorylation of p38 MAPK.


Assuntos
Fígado/citologia , NADPH Oxidases/fisiologia , Fator de Crescimento Derivado de Plaquetas/farmacologia , Animais , Becaplermina , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Ativação Enzimática , Sequestradores de Radicais Livres/farmacologia , Humanos , Isoenzimas/metabolismo , Cirrose Hepática/patologia , Camundongos , NADPH Oxidases/metabolismo , Oniocompostos/farmacologia , Fosforilação/efeitos dos fármacos , Porfirinas/farmacologia , Proteínas Proto-Oncogênicas c-sis , Espécies Reativas de Oxigênio/antagonistas & inibidores , Espécies Reativas de Oxigênio/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
5.
Biochem Biophys Res Commun ; 317(2): 335-41, 2004 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-15063762

RESUMO

The outcome of hepatitis C virus (HCV) infection varies among individuals, but the genetic factors involved remain unknown. We conducted a population-based association study in which 238 Japanese individuals positive for anti-HCV antibody were genotyped for 269 single nucleotide polymorphisms (SNPs) in 103 candidate genes that might influence the course of infection. Altogether, 50 SNPs in 32 genes were listed. Genetic polymorphisms in IL4, IL8RB, IL10RA, PRL, ADA, NFKB1, GRAP2, CABIN1, IFNAR2, IFI27, IFI41, TNFRSF1A, ALDOB, AP1B1, SULT2B1, EGF, EGFR, TGFB1, LTBP2, and CD4 were associated with persistent viremia (P < 0.05), whereas those in IL1B, IL1RL1, IL2RB, IL12RB1, IL18R1, STAT5A, GRAP2, CABIN1, IFNAR1, Mx1, BMP8, FGL1, LTBP2, CD34, and CD80 were associated with different serum alanine aminotransferase levels in HCV carriers (P < 0.05). The sorted genes allow us to draw novel hypotheses for future studies of HCV infection to ultimately identify bona fide genes and their variations.


Assuntos
Predisposição Genética para Doença/epidemiologia , Predisposição Genética para Doença/genética , Testes Genéticos/métodos , Hepatite C/epidemiologia , Hepatite C/genética , Fenótipo , Viremia/epidemiologia , Viremia/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Comorbidade , Progressão da Doença , Feminino , Variação Genética , Hepatite C/sangue , Humanos , Japão/epidemiologia , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único/genética , Viremia/sangue
6.
Hepatol Res ; 27(4): 309-314, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14662119

RESUMO

OBJECTIVES: Interleukin-10 (IL-10) has been implicated in immune deficiency in patients with cancer. The relationship of this cytokine as measured in serum to anti-tumor immunity and prognosis was investigated in unresectable hepatocellular carcinoma. METHODS: This study consisted of 74 consecutive patients with unresectable hepatocellular carcinoma (median age, 65 years). Forty-four healthy age-matched subjects and 32 patients with cirrhosis but no carcinoma served as controls. Patients with hepatocellular carcinoma were divided into those with serum IL-10 concentrations above (high group, n=39) or below (low group, n=35) 10pg/ml. RESULTS: Age, gender, Child-Pugh grade, and tumor stage distributions were similar in high and low groups. The patients of high group showed lower in lymphokine-activated killer (LAK) and natural killer (NK) activities than those of low group (P<0.01 and 0.01, respectively). Serum IL-10 concentration was a significant factor contributing to low activities of LAK and NK by logistic regression analysis (P<0.05 and 0.05, respectively). The high group had a significantly shorter survival (median, 3 months) than low group (median, 12 months; P<0.02, generalized Wilcoxon test). CONCLUSIONS: These data suggest that serum IL-10 concentration is a possible factor contributing to poor prognosis and low anti-tumor immunity in patients with unresectable hepatocellular carcinoma.

7.
Hepatology ; 38(6): 1401-9, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14647051

RESUMO

The asialoglycoprotein receptor (ASGPR) is abundantly expressed on the sinusoidal surfaces of hepatocytes. We aimed to clarify the clinical significance of the regional distribution of ASGPRs in the human liver, especially in chronic viral hepatitis. Eighteen volunteers, 34 patients with chronic hepatitis, and 33 patients with cirrhosis (11/Child-Pugh A, 11/Child-Pugh B, 11/Child-Pugh C) were studied using a newly developed, conventional technetium-99m-diethylenetriaminepentaacetic acid-galactosyl human serum albumin ((99m)Tc-GSA), single photon emission computed tomography (SPECT) method. Using Cantlie's line as a guide, ASGPR dynamics were analyzed separately in the right and left lobes, as well as in the whole liver, using novel indices (the liver uptake ratio [LUR] and the liver uptake density [LUD], which reflect the amount and density of ASGPRs in the liver, respectively). Mean LUR and LUD values for the whole liver and the right and left lobes decreased with increasing progression of chronic viral hepatitis. The LUR for the whole liver correlated well with parameters measuring the hepatic functional reserve and the platelet count. The right LUR correlated particularly well with conventional liver function tests, and comparison of the right LUD with histologic findings showed that it was a good indicator of periportal and/or bridging necrosis and fibrosis. In conclusion, our (99m)Tc-GSA SPECT method was clinically useful in evaluating regional hepatic function and the progression of chronic viral hepatitis using dynamic changes in ASGPRs.


Assuntos
Receptor de Asialoglicoproteína/análise , Fígado/química , Agregado de Albumina Marcado com Tecnécio Tc 99m , Pentetato de Tecnécio Tc 99m , Tomografia Computadorizada de Emissão de Fóton Único , Adulto , Idoso , Idoso de 80 Anos ou mais , Progressão da Doença , Feminino , Hepatite Crônica/metabolismo , Humanos , Fígado/diagnóstico por imagem , Testes de Função Hepática , Masculino , Pessoa de Meia-Idade
9.
J Med Virol ; 71(1): 56-61, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12858409

RESUMO

The natural course of hepatitis C virus (HCV) infection has not been fully elucidated. To investigate whether HCV is spontaneously eliminated in chronic carriers, a long-term population-based cohort study was conducted on 435 chronic HCV carriers. Individual characteristics, serum HCV RNA, and liver function tests were analyzed, and ultra sonography (US) was performed in all subjects. Subjects were followed up for 7.2 +/- 2.4 years (mean +/- SD). Serum HCV RNA was spontaneously eliminated in 16/435 (3.7%) individuals during this period; thus, the incidence of spontaneous elimination of serum HCV RNA was 0.5%/year/person. Multivariate analysis revealed that both a low value of ZTT and no US finding of chronic liver disease were associated with spontaneous viral elimination in HCV carriers. Three of these 16 individuals had chronic hepatitis, and 13 of them had normal ALT levels. When the neutralization of binding (NOB) assay that evaluates inhibition of the HCV envelope-2 protein binding to human cells was examined using sera from these 16 individuals, the NOB antibody was detected in only 3 cases with chronic hepatitis. These results suggest that serum HCV RNA is spontaneously eliminated in chronic HCV carriers in a population, and that the development of NOB antibody is associated with a natural resolution of chronic hepatitis in the minority of them.


Assuntos
Hepacivirus/genética , Hepatite C Crônica/virologia , RNA Viral/sangue , Adulto , Idoso , Estudos de Coortes , Feminino , Hepatite C Crônica/sangue , Hepatite C Crônica/enzimologia , Humanos , Masculino , Pessoa de Meia-Idade
10.
Biochem Biophys Res Commun ; 304(4): 691-5, 2003 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-12727209

RESUMO

Bone marrow (BM) stem cells have been shown to differentiate into liver cells. It remains difficult to sort and culture BM stem cells, and the gene expression of liver-specific proteins in these cells has not been fully investigated. We used a negative selective magnetic cell separation system to obtain stem cell-enriched BM cells. The cells obtained were cultured with hepatocytes or with hepatocyte growth factor (HGF), and the differentiation of BM cells into cells expressing liver-specific genes, hepatocyte nuclear factor (HNF) 1alpha, cytokeratin (CK) 8, alpha-fetoprotein (AFP), and albumin was investigated by the reverse transcription-polymerase chain reaction. We also investigated the gene expressions of Notch receptor-1 (Notch-1) and its ligand Jagged-1 in BM cell differentiation. Sorted BM cells showed positive for Sca-1 (Ataxin-1) by immunofluorescence staining. Fluorescence activated cell sorter analysis showed that 32.6% of sorted BM cells had a high level of expression of the hematopoietic stem cell marker CD90 (Thy-1). When cultured with hepatocytes, these cells expressed the liver-specific genes HNF1alpha and CK8 on culture day 3, AFP and albumin on culture day 7. When cultured with HGF (20ng/ml), the cells expressed HNF1alpha on day 3 and CK8 on day 7. Gene expressions of Notch-1 and Jagged-1 were detected in cultured BM cells on day 3. These results suggest that the negative selective magnetic cell separation system is useful for the rapid preparation of stem cell-enriched BM cells, and that the Notch signaling pathway plays a role in BM cell differentiation into a hepatocyte lineage in vitro.


Assuntos
Células da Medula Óssea/fisiologia , Diferenciação Celular/fisiologia , Hepatócitos/fisiologia , Proteínas de Membrana/metabolismo , Receptores de Superfície Celular , Fatores de Transcrição , Animais , Células da Medula Óssea/citologia , Proteínas de Ligação ao Cálcio , Células Cultivadas , Hepatócitos/citologia , Separação Imunomagnética , Peptídeos e Proteínas de Sinalização Intercelular , Proteína Jagged-1 , Masculino , Proteínas de Membrana/genética , Fenótipo , Proteínas/metabolismo , Ratos , Ratos Sprague-Dawley , Receptor Notch1 , Proteínas Serrate-Jagged , Transdução de Sinais/fisiologia , Transativadores/genética , Transativadores/metabolismo
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