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1.
J Frailty Aging ; 13(3): 218-223, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39082765

RESUMO

BACKGROUND: Finger tapping impairment and frailty share overlapping pathophysiology and symptoms in older adults, however, the relationship between each other has not been previously studied. OBJECTIVES: To investigate how finger tapping movements correlate with frail status in older Japanese adults. DESIGN, SETTING, AND PARTICIPANTS: Data were from a cross-sectional study called the Cognition and Activity in Rural Environment of Hokkaido Senior Survey 2018. A total of 244 community-dwelling older adults (mean age 75.3 years) were included. MEASUREMENTS: Participants underwent physical examinations, gait and finger tapping tests, and completed self-administered questionnaires. Frailty was assessed using Fried's frailty phenotype, and factor analysis was conducted to extract relevant finger tapping factors. Multinomial logistic regression was employed to analyze associations, generating adjusted odds ratios. RESULTS: Of the participants, 18 were frail, and 145 pre-frail. Analysis identified three distinct finger tapping patterns: "Range of Motion - Nondominant Hand," "Variability - Dominant Hand - Anti," and "Variability - Nondominant Hand - Anti." These patterns showed significant associations with aspects of Fried's frailty phenotype, particularly low physical activity (P = 0.002), weakness (P = 0.003), and slowness (P = 0.004). A larger range of motion in the nondominant hand correlated with a lower frailty risk (Odds Ratio: 0.09, 95% CI: 0.02-0.46), while higher variability in the same hand increased the risk of pre-frailty (Odds Ratio: 2.19, 95% CI: 1.09-4.39). CONCLUSION: Finger tapping movements are significantly associated with frailty status as determined by Fried's phenotype. The findings underscore the importance of further longitudinal studies to understand the relationship between motor function and frailty.


Assuntos
Idoso Fragilizado , Fragilidade , Avaliação Geriátrica , Humanos , Idoso , Masculino , Feminino , Estudos Transversais , Japão/epidemiologia , Fragilidade/fisiopatologia , Fragilidade/epidemiologia , Fragilidade/diagnóstico , Idoso Fragilizado/estatística & dados numéricos , Avaliação Geriátrica/métodos , Idoso de 80 Anos ou mais , Dedos/fisiologia , Vida Independente , Movimento/fisiologia , População do Leste Asiático
2.
J Hosp Infect ; 150: 134-144, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38901769

RESUMO

BACKGROUND: Surgical site infections (SSIs) are common complications after abdominal surgery. AIM: To compare which suture devices could reduce the incidence of incisional surgical site infections (SSIs) after gastrointestinal surgery using a systematic review and network meta-analysis. METHODS: The CENTRAL, PubMed, and ICHUSHI-Web databases were searched from January 1st, 2000, to December 31st, 2022, for randomized clinical trials (RCTs) comparing the incidence of incisional SSI after gastrointestinal surgery among patients treated with different surgical suture devices, including non-absorbable sutures, absorbable sutures, skin staplers, and tissue adhesives (last searched in August 23th, 2023). The risk of bias was assessed using the criteria of the Cochrane Handbook for Systematic Reviews of Interventions. To estimate the pooled odds ratios (ORs) for each comparison, a fixed-effect inverse-variance model based on the Mantel-Haenszel approach was employed. FINDINGS: A total of 18 RCTs with 5496 patients were included in this study. The overall SSIs in absorbable sutures were significantly lower than those in skin staplers (OR: 0.77; 95% confidence intervals (CI): 0.63-0.95) and non-absorbable sutures (OR: 0.62; 95% CI: 0.39-0.99), whereas SSIs in absorbable sutures were not significantly different from the SSIs in tissue adhesive. The highest P-score was 0.91 for absorbable sutures. A funnel plot for estimating the heterogeneity of the studies revealed that a publication bias would be minimal (Egger test, P = 0.271). CONCLUSION: This study showed that absorbable sutures reduced incisional SSIs in gastrointestinal surgical operations compared to any other suture devices.


Assuntos
Procedimentos Cirúrgicos do Sistema Digestório , Infecção da Ferida Cirúrgica , Suturas , Infecção da Ferida Cirúrgica/epidemiologia , Infecção da Ferida Cirúrgica/prevenção & controle , Infecção da Ferida Cirúrgica/etiologia , Humanos , Incidência , Suturas/efeitos adversos , Procedimentos Cirúrgicos do Sistema Digestório/efeitos adversos , Ensaios Clínicos Controlados Aleatórios como Assunto , Metanálise em Rede
3.
Tech Coloproctol ; 28(1): 71, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38916755

RESUMO

BACKGROUNDS: Anastomotic leakage (AL) represents a major complication after rectal low anterior resection (LAR). Transanal drainage tube (TDT) placement offers a potential strategy for AL prevention; however, its efficacy and safety remain contentious. METHODS: A systematic review and meta-analysis were used to evaluate the influence of TDT subsequent to LAR as part of the revision of the surgical site infection prevention guidelines of the Japanese Society of Surgical Infectious Diseases (PROSPERO registration; CRD42023476655). We searched each database, and included randomized controlled trials (RCTs) and observational studies (OBSs) comparing TDT and non-TDT outcomes. The main outcome was AL. Data were independently extracted by three authors and random-effects models were implemented. RESULTS: A total of three RCTs and 18 OBSs were included. RCTs reported no significant difference in AL rate between the TDT and non-TDT groups [relative risk (RR): 0.69, 95% confidence interval (CI) 0.42-1.15]. OBSs reported that TDT reduced AL risk [odds ratio (OR): 0.45, 95% CI 0.31-0.64]. In the subgroup excluding diverting stoma (DS), TDT significantly lowered the AL rate in RCTs (RR: 0.57, 95% CI 0.33-0.99) and OBSs (OR: 0.41, 95% CI 0.27-0.62). Reoperation rates were significantly lower in the TDT without DS groups in both RCTs (RR: 0.26, 95% CI 0.07-0.94) and OBSs (OR: 0.40, 95% CI 0.24-0.66). TDT groups exhibited a higher anastomotic bleeding rate only in RCTs (RR: 4.28, 95% CI 2.14-8.54), while shorter hospital stays were observed in RCTs [standard mean difference (SMD): -0.44, 95% CI -0.65 to -0.23] and OBSs (SMD: -0.54, 95% CI -0.97 to -0.11) compared with the non-TDT group. CONCLUSIONS: A universal TDT placement cannot be recommended for all rectal LAR patients. Some patients may benefit from TDT, such as patients without DS creation. Further investigation is necessary to identify the specific beneficiaries.


Assuntos
Canal Anal , Fístula Anastomótica , Drenagem , Protectomia , Ensaios Clínicos Controlados Aleatórios como Assunto , Reto , Humanos , Fístula Anastomótica/prevenção & controle , Fístula Anastomótica/etiologia , Drenagem/instrumentação , Drenagem/métodos , Protectomia/efeitos adversos , Protectomia/métodos , Reto/cirurgia , Canal Anal/cirurgia , Neoplasias Retais/cirurgia , Resultado do Tratamento , Feminino , Masculino , Estudos Observacionais como Assunto , Pessoa de Meia-Idade
4.
J Hosp Infect ; 146: 174-182, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37734678

RESUMO

The aim of this study was to conduct a systematic review and meta-analysis of the efficacy of fascial closure using antimicrobial-sutures specifically for the prevention of surgical site infections (SSIs) in gastrointestinal surgery, as part of the revision of the SSI prevention guidelines of the Japanese Society of Surgical Infectious Diseases (JSSI). We searched CENTRAL, PubMed and ICHUSHI-Web in May 2023, and included randomized controlled trials (RCTs) comparing antimicrobial-coated and non-coated sutures for fascial closure in gastrointestinal surgery (PROSPERO No. CRD42023430377). Three authors independently screened the RCTs. We assessed the risk of bias and the GRADE criteria for the extracted data. The primary outcome was incisional SSI and the secondary outcomes were abdominal wall dehiscence and the length of postoperative hospital stay. This study was supported partially by the JSSI. A total of 10 RCTs and 5396 patients were included. The use of antimicrobial-coated sutures significantly lowered the risk of incisional SSIs compared with non-coated suture (risk ratio: 0.79, 95% confidence intervals: 0.64-0.98). In subgroup analyses, antimicrobial-coated sutures reduced the risk of SSIs for open surgeries, and when monofilament sutures were used. Antimicrobial-coated sutures did not reduce the incidence of abdominal wall dehiscence and the length of hospital stay compared with non-coated sutures. The certainty of the evidence was rated as moderate according to the GRADE criteria, because of risk of bias. In conclusion, the use of antimicrobial-coated sutures for fascial closure in gastrointestinal surgery is associated with a significantly lower risk of SSI than non-coated sutures.

5.
J Phys Condens Matter ; 35(33)2023 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-37172593

RESUMO

Cooperative motions are important for understanding the divergence of viscosity of glassy materials at a finite temperature, since the elementary process of the structural relaxation occurs within the smallest cooperative region as suggested by Adam and Gibbs. On the basis of the definition of a cooperatively rearranging region (CRR) by Adam and Gibbs and by Odagaki, we determine the size of CRR for the Kob-Andersen model as a function of temperature using molecular dynamics simulations. We first confine particles in a spherical region and, varying the radius of that region, we determine the CRR size as the smallest radius of the region in which particles can change their relative positions. The size of the CRR increases as the temperature is reduced and seems to diverge below the glass transition temperature. The temperature dependence of the number of particles in the CRR obeys the equation derived from the Adam-Gibbs relation and the Vogel-Fulcher-Tammann equation.

7.
Clin Genet ; 94(3-4): 362-367, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29797509

RESUMO

Neurodevelopmental disorder with microcephaly, hypotonia, and variable brain anomalies (NMIHBA) (OMIM #617481) is an autosomal recessive disease characterized by progressive microcephaly, plagiocephaly, hypotonia, spastic quadriparesis, global developmental delay, intellectual disability, optic features and abnormal brain magnetic resonance imaging (MRI). NMIHBA was recently reported to be caused by PRUNE1 mutations. Eight mutations have been reported in 13 unrelated families. Here, we report 3 PRUNE1 mutations in 1 Caucasian and 3 Japanese families. One recurrent missense mutation (p.Asp106Asn) was previously reported in Turkish and Italian families, while the other 2 mutations (p.Leu18Serfs*8 and p.Cys180*) are novel. We also show that mutant PRUNE1 mRNA can be subject to nonsense-mediated mRNA decay. The patients presented in this study showed atypical NMIHBA phenotypes with no progressive microcephaly. Furthermore, one Caucasian case had significant macrocephaly; therefore, patients with PRUNE1 mutations can exhibit a broad and heterogeneous spectrum of phenotypes.


Assuntos
Encéfalo/anormalidades , Microcefalia/genética , Hipotonia Muscular/genética , Monoéster Fosfórico Hidrolases/genética , Encéfalo/diagnóstico por imagem , Criança , Feminino , Humanos , Itália , Imageamento por Ressonância Magnética , Masculino , Mutação de Sentido Incorreto , Linhagem , RNA Mensageiro/genética , Turquia
8.
J Chem Phys ; 148(1): 014501, 2018 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-29306298

RESUMO

Molecular dynamics simulations are performed on simple models composed of monoatomic Lennard-Jones atoms for which the repulsive interaction is the same but the attractive part is tuned. We investigate the precise role of the attractive part of the interaction potential on different structural, dynamical, and thermodynamical properties of these systems in the liquid and crystalline states. It includes crystallization trends for which the main physical ingredients involved have been computed: the diffusion coefficient, the Gibbs energy difference between the liquid and the crystalline state, and the crystal-liquid interfacial free energy. Results are compared with predictions from the classical nucleation theory including transient and steady-state regimes at moderate and deeper undercooling. The question of the energetic and entropic impact of the repulsive and attractive part of the interaction potential towards crystallization is also addressed.

9.
Clin Genet ; 93(2): 266-274, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28556953

RESUMO

The seizure threshold 2 (SZT2) gene encodes a large, highly conserved protein that is associated with epileptogenesis. In mice, Szt2 is abundantly expressed in the central nervous system. Recently, biallelic SZT2 mutations were found in 7 patients (from 5 families) presenting with epileptic encephalopathy with dysmorphic features and/or non-syndromic intellectual disabilities. In this study, we identified by whole-exome sequencing compound heterozygous SZT2 mutations in 3 patients with early-onset epileptic encephalopathies. Six novel SZT2 mutations were found, including 3 truncating, 1 splice site and 2 missense mutations. The splice-site mutation resulted in skipping of exon 20 and was associated with a premature stop codon. All individuals presented with seizures, severe developmental delay and intellectual disabilities with high variability. Brain MRIs revealed a characteristic thick and short corpus callosum or a persistent cavum septum pellucidum in each of the 2 cases. Interestingly, in the third case, born to consanguineous parents, had unexpected compound heterozygous missense mutations. She showed microcephaly despite the other case and previous ones presenting with macrocephaly, suggesting that SZT2 mutations might affect head size.


Assuntos
Epilepsia Generalizada/genética , Deficiência Intelectual/genética , Proteínas do Tecido Nervoso/genética , Espasmos Infantis/genética , Pré-Escolar , Epilepsia Generalizada/diagnóstico por imagem , Epilepsia Generalizada/patologia , Feminino , Humanos , Lactente , Deficiência Intelectual/diagnóstico por imagem , Deficiência Intelectual/patologia , Imageamento por Ressonância Magnética , Masculino , Mutação de Sentido Incorreto/genética , Linhagem , Sítios de Splice de RNA/genética , Espasmos Infantis/diagnóstico por imagem , Espasmos Infantis/patologia , Sequenciamento do Exoma
11.
Clin Genet ; 93(3): 577-587, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-28940419

RESUMO

Epilepsies are common neurological disorders and genetic factors contribute to their pathogenesis. Copy number variations (CNVs) are increasingly recognized as an important etiology of many human diseases including epilepsy. Whole-exome sequencing (WES) is becoming a standard tool for detecting pathogenic mutations and has recently been applied to detecting CNVs. Here, we analyzed 294 families with epilepsy using WES, and focused on 168 families with no causative single nucleotide variants in known epilepsy-associated genes to further validate CNVs using 2 different CNV detection tools using WES data. We confirmed 18 pathogenic CNVs, and 2 deletions and 2 duplications at chr15q11.2 of clinically unknown significance. Of note, we were able to identify small CNVs less than 10 kb in size, which might be difficult to detect by conventional microarray. We revealed 2 cases with pathogenic CNVs that one of the 2 CNV detection tools failed to find, suggesting that using different CNV tools is recommended to increase diagnostic yield. Considering a relatively high discovery rate of CNVs (18 out of 168 families, 10.7%) and successful detection of CNV with <10 kb in size, CNV detection by WES may be able to surrogate, or at least complement, conventional microarray analysis.


Assuntos
Variações do Número de Cópias de DNA , Epilepsia/genética , Estudos de Associação Genética , Predisposição Genética para Doença , Testes Genéticos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Alelos , Criança , Pré-Escolar , Hibridização Genômica Comparativa , Biologia Computacional/métodos , Epilepsia/diagnóstico , Exoma , Feminino , Estudos de Associação Genética/métodos , Testes Genéticos/métodos , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Sequenciamento do Exoma , Adulto Jovem
13.
Anaesth Intensive Care ; 41(4): 523-8, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23808513

RESUMO

This study evaluated the usefulness of asialoglycoprotein receptor scintigraphy with 99mTc-galactosyl human serum albumin (99mTc-GSA scintigraphy) as an early predictor for prognosis of acute liver failure. Forty-eight patients with acute liver failure and without a past history of chronic liver disease were enrolled. Patients were divided into survival and non-survival groups by 28-day mortality. 99mTc-GSA scintigraphy to detect uptake ratio of the heart at 15 minutes to that at three minutes (HH15) and uptake ratio of the liver at 15 minutes to the liver plus the heart at 15 minutes (LHL15), and measurements of serum total bilirubin, hepatocyte growth factor and prothrombin time were performed immediately after the diagnosis of acute liver failure. Areas under the receiver operating characteristic curves were used to compare the prognostic ability of total bilirubin, hepatocyte growth factor, prothrombin time, HH15 ratio, LHL15 ratio and the model for end-stage liver disease score. Clinical characteristics of patients in the survival group (n=20) and in the non-survival group (n=28) were not significantly different. HH15 and LHL15 uptake ratios in the survival group were 0.670 and 0.875, and they were significantly lower and higher than those in the non-survival group, respectively. All patients with LHL15 <0.760 died, and the area under the receiver operating characteristic curve for LHL15 were significantly larger than the areas under the receiver operating characteristic curves of serum variables and model for end-stage liver disease score. In summary, in patients with acute liver failure without chronic liver disease, HH15 and LHL15 of 99mTc-GSA scintigraphy are more useful variables in predicting prognosis than serum variables and model for end-stage liver disease score.


Assuntos
Receptor de Asialoglicoproteína/metabolismo , Falência Hepática Aguda/diagnóstico por imagem , Falência Hepática Aguda/metabolismo , Compostos Radiofarmacêuticos , Agregado de Albumina Marcado com Tecnécio Tc 99m , Estudos de Coortes , Doença Hepática Terminal/diagnóstico por imagem , Feminino , Humanos , Testes de Função Hepática , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Curva ROC , Cintilografia , Estudos Retrospectivos , Sobrevida
15.
J Neurol Neurosurg Psychiatry ; 80(9): 1050-2, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19684239

RESUMO

BACKGROUND: The occurrence of duplications of the amyloid precursor protein gene (APP) has been described in European families with early-onset familial Alzheimer disease (EO-FAD) and cerebral amyloid angiopathy. However, the contribution of APP duplication to the development of AD in other ethnic populations remains undetermined. METHODS: The occurrence of APP duplication in probands from 25 families with FAD and 11 sporadic EO-AD cases in the Japanese population was examined by quantitative PCR and microarray-based comparative genomic hybridisation analyses. APP expression level was determined by real-time quantitative reverse-transcription (RT) PCR analysis using mRNA extracted from the peripheral blood of the patients. RESULTS: We identified APP locus duplications in two unrelated EO-FAD families. The duplicated genomic regions in two patients of these families differed from each other. No APP duplication was found in the late-onset FAD families or sporadic EO-AD patients. The patients with APP duplication developed insidious memory disturbance in their fifties without intracerebral haemorrhage and epilepsy. Quantitative RT-PCR analysis showed the increased APP mRNA expression levels in these patients compared with those in age- and sex-matched controls. CONCLUSIONS: Our results suggest that APP duplication should be considered in patients with EO-FAD in various ethnic groups, and that increased APP mRNA expression level owing to APP duplication contributes to AD development.


Assuntos
Doença de Alzheimer/genética , Precursor de Proteína beta-Amiloide/genética , Duplicação Gênica , Idade de Início , Doença de Alzheimer/epidemiologia , Doença de Alzheimer/patologia , Apolipoproteínas E/genética , Atrofia , Encéfalo/patologia , Estudos de Coortes , DNA/genética , Feminino , Dosagem de Genes , Humanos , Japão/epidemiologia , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Linhagem , RNA Mensageiro/sangue , Proteínas tau/líquido cefalorraquidiano
17.
Clin Genet ; 74(4): 384-91, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18505455

RESUMO

Haploinsufficiency of the NSD1 gene due to 5q35 microdeletions or intragenic mutations causes Sotos syndrome (SoS). In 46 of the 49 Japanese deletion cases, common deletion breakpoints were located at two flanking low copy repeats (LCRs), implying that non-allelic homologous recombination (NAHR) between LCRs is the major mechanism for the common deletion. In the other three cases of atypical deletions, the mechanism(s) of deletions remains unanswered. We characterized the atypical microdeletions using fluorescence in situ hybridization (FISH), quantitative real-time polymerase chain reaction (qPCR), and Southern blot hybridization. All the deletion breakpoints in the three cases were successfully determined at the nucleotide level. Two deletions are 1.07 Mb (SoS19) and 1.23 Mb (SoS109) in size, and another consisted of two deletions with sizes of 28 kb and 0.72 Mb, intervened by an intact 29-kb segment (SoS44). All deletions were smaller than a typical 1.9-Mb common deletion. Alu elements were identified in both deletion breakpoints in SoS19, one of deletion breakpoints in SoS109, and both deletion breakpoints of the proximal 28-kb deletion in SoS44. Alu-mediated NAHR is strongly suggested at least in two of atypical deletions. Finally, qPCR is a very useful method to determine deletion breakpoints even in repeat-related regions.


Assuntos
Anormalidades Múltiplas/genética , Elementos Alu/genética , Cromossomos Humanos Par 5/genética , Anormalidades Craniofaciais/genética , Transtornos do Crescimento/genética , Deficiência Intelectual/genética , Deleção de Sequência/genética , Sequência de Bases , Quebras de DNA de Cadeia Dupla , Humanos , Hibridização in Situ Fluorescente , Modelos Genéticos , Dados de Sequência Molecular , Recombinação Genética , Síndrome
18.
Eur Surg Res ; 38(6): 522-32, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17047332

RESUMO

BACKGROUND/AIM: Liver regeneration is a finely tuned process that is closely regulated by multiple cell cycle steps. Although the portal blood flow affects liver regeneration, the molecular mechanism by which the blood flow regulates gene expression and liver function is largely unknown. The aim of this study was to investigate the molecular effect of portal blood flow on hepatocyte proliferation and gene regulation during liver regeneration. MATERIALS AND METHODS: We developed a simple surgical rat model to investigate the relation between portal blood flow and liver regeneration by partially ligating the portal trunk with 8-0 Proline sutures under microscopy to reduce the blood flow by 40%. We investigated recovery of liver volume, DNA synthesis, and gene expression associated with cell cycle regulators, comparing partially hepatectomized (PH) rats without (PH group; n = 30) and with partial portal ligation (PHPL group; n = 30) for 7 days after the operation. RESULTS: The hepatic tissue blood flow and the recovery ratio between liver weight and body weight in the PHPL group were significantly lower than in the PH group after hepatectomy. The peak 5-bromo-2'-deoxyuridine labeling index in the PHPL group was delayed and weak compared with the PH group. The expression of CT-1 and cyclin D, E, and B mRNAs indicated that the liver regeneration in the PHPL group was delayed and weak. In addition, there was reciprocal expression of C/EBPalpha and C/EBPbeta mRNAs, an observation supported by their nuclear protein levels. Furthermore, the cytochrome P-450 protein level in the PHPL group was higher than that in the PH group 1 day after hepatectomy. CONCLUSION: The portal blood flow regulates the activity of liver regeneration and the gene expression associated with cell cycle regulators, while the functions are maintained.


Assuntos
Regeneração Hepática/fisiologia , Fígado/irrigação sanguínea , Sistema Porta/fisiologia , Animais , Bromodesoxiuridina/metabolismo , Proteína alfa Estimuladora de Ligação a CCAAT/genética , Proteína beta Intensificadora de Ligação a CCAAT/genética , Ciclinas/genética , Citocinas/genética , Hepatectomia , Imuno-Histoquímica , Masculino , RNA Mensageiro/análise , Ratos , Ratos Sprague-Dawley
19.
J Cell Physiol ; 189(1): 106-19, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11573209

RESUMO

Liver transplantation is the only clinically effective method of treating acute liver failure. However, wider application of this therapeutic modality is restricted primarily by shortage of donor organs. In the search for alternative methods of liver replacement therapy, investigators have focused on transplantation of normal allogeneic hepatocytes and on the development of liver support systems utilizing isolated hepatocytes. Since all human livers suitable for cell harvest are being used for transplantation, hepatocyte therapy using human tissue would require growing of cells in vitro. Unfortunately, although hepatocytes have tremendous capacity to proliferate in vivo, their ability to grow in culture is severely limited. Stromal cells from bone marrow and other blood-forming organs have been found to support hematopoiesis. In this paper, we show that bone marrow-derived stromal cells (BMSCs) enhance proliferation and support differentiation of rat hepatocytes in culture. Further, we demonstrate that in hepatocyte/BMSC co-cultures, clonal expansion of small hepatocytes (SH) is increased. Using semipermeable membrane cultures, we established that direct cell-cell contact is necessary for stimulation of cell proliferation. We also show that BMSCs which are in direct contact with hepatocytes and SH colonies express Jagged1. This suggests a potential role for Notch signaling in the observed effects. Finally, we present evidence that the expression and activity of liver specific transcription factors, CCAAT/enhancer binding proteins and liver specific key enzymes such as tryptophan 2,3-dioxygenase, are improved in hepatocyte/BMSC co-cultures. In conclusion, results of this study indicate that BMSCs could facilitate proliferation and differentiation of primary rat hepatocytes and their progenitors (SH) in vitro.


Assuntos
Células da Medula Óssea/citologia , Hepatócitos/citologia , Células Estromais/fisiologia , Animais , Bromodesoxiuridina/metabolismo , Proteínas Estimuladoras de Ligação a CCAAT/biossíntese , Proteínas Estimuladoras de Ligação a CCAAT/genética , Proteínas de Ligação ao Cálcio , Comunicação Celular , Técnicas de Cultura de Células/métodos , Diferenciação Celular , Divisão Celular , Células Cultivadas , Hepatócitos/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular , Proteína Jagged-1 , Cinética , Masculino , Proteínas de Membrana , Fenótipo , Biossíntese de Proteínas , Proteínas/genética , RNA Mensageiro/biossíntese , Ratos , Ratos Sprague-Dawley , Proteínas Serrate-Jagged , Células-Tronco/citologia , Células-Tronco/metabolismo
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