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1.
Matern Child Nutr ; : e13677, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38961562

RESUMO

Poor measurement quality has set back the utility of anthropometry in defining childhood malnutrition, prompting calls for alternative measurement techniques. This study aimed to assess the reliability of anthropometric measurements using a digital height board in comparison to an analog height board in Namibian children under 5 years of age. A cross-sectional, descriptive study was conducted (n = 425) between the age of 6 and 59 months, using anthropometric measurements of weight, height and mid-upper arm circumference. Two trained enumerators each collected four height measurements of each child: two using an analog height board and two using a digi-board. The repeated height measurements between and within the enumerators were used to determine intra- and interobserver reliability. Reliability of the digi-board was assessed using the technical error of measurement (TEM), relative TEM (%TEM), intraclass correlation and a Bland-Altman analysis to assess the agreement between the two methods. In all these assessments, the analog height board was considered as the gold standard and used for comparison. The digi-board showed superiority to the analog height board in terms of reliability (analog TEM = 0.22, digi-board TEM = 0.16). Although the digi-board has potential to improve child anthropometry, further clinical and large survey studies are needed to validate the used of this tool in routine population-based surveys.

4.
Gastroenterology ; 142(4): 897-906, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22178588

RESUMO

BACKGROUND & AIMS: Hepatocyte growth factor/scatter factor (HGF/SF) stimulates hepatocyte DNA synthesis and protects against apoptosis; in vivo it promotes liver regeneration and reduces fibrosis. However, its therapeutic value is limited by its complex domain structure, high cost of production, instability, and poor tissue penetration due to sequestration by heparin sulfate proteoglycans (HSPGs). METHODS: Using protein engineering techniques, we created a full-length form of HGF/SF (called HP21) and a form of the small, naturally occurring HGF/SF fragment, NK1 (called 1K1), which have reduced affinity for HSPG. We characterized the stability and proliferative and anti-apoptotic effects of these variants in primary human hepatocytes and in rodents. RESULTS: Analytical ultracentrifugation showed that 1K1 and NK1 were more stable than the native, full-length protein. All 4 forms of HGF/SF induced similar levels of DNA synthesis in human hepatocytes; 1K1 and NK1 required heparin, an HSPG analogue, for full agonistic activity. All the proteins reduced levels of Fas ligand-mediated apoptosis, reducing the activity of caspase-3/7 and cleavage of poly(adenosine diphosphate-ribose) polymerase. 1K1 was more active than NK1 in rodents; in healthy mice, 1K1 significantly increased hepatocyte DNA synthesis, and in mice receiving carbon tetrachloride, it reduced fibrosis. In rats, after 70% partial hepatectomy, daily administration of 1K1 for 5 days significantly increased liver mass and the bromodeoxyuridine labeling index compared with mice given NK1. CONCLUSIONS: 1K1, an engineered form of the small, naturally occurring HGF/SF fragment NK1, has reduced affinity for HSPG and exerts proliferative and antiapoptotic effects in cultured hepatocytes. In rodents, 1K1 has antifibrotic effects and promotes liver regeneration. The protein has better stability and is easier to produce than HGF/SF and might be developed as a therapeutic for acute and chronic liver disease.


Assuntos
Proliferação de Células/efeitos dos fármacos , Fator de Crescimento de Hepatócito/farmacologia , Hepatócitos/efeitos dos fármacos , Cirrose Hepática/prevenção & controle , Regeneração Hepática/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fragmentos de Peptídeos/farmacologia , Engenharia de Proteínas , Animais , Apoptose , Sítios de Ligação , Tetracloreto de Carbono , Caspase 3/metabolismo , Caspase 7/metabolismo , Células Cultivadas , Replicação do DNA , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Proteína Ligante Fas/metabolismo , Proteoglicanas de Heparan Sulfato/metabolismo , Hepatectomia , Fator de Crescimento de Hepatócito/química , Fator de Crescimento de Hepatócito/genética , Fator de Crescimento de Hepatócito/metabolismo , Hepatócitos/metabolismo , Hepatócitos/patologia , Humanos , Fígado/metabolismo , Fígado/patologia , Fígado/cirurgia , Cirrose Hepática/induzido quimicamente , Cirrose Hepática/metabolismo , Cirrose Hepática/patologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Modelos Moleculares , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/genética , Fragmentos de Peptídeos/metabolismo , Poli(ADP-Ribose) Polimerases/metabolismo , Conformação Proteica , Estabilidade Proteica , Ratos , Ratos Sprague-Dawley , Proteínas Recombinantes/metabolismo , Fatores de Tempo , Ultracentrifugação
5.
Dig Dis Sci ; 58(9): 2528-41, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23839340

RESUMO

BACKGROUND: Enhanced cell expression of MAdCAM-1 is critical in tissue recruitment of lymphocytes in response to stimuli expressing the α4ß7 integrin. MAdCAM-1 is well characterized in gut mucosa with emerging evidence of hepatic expression. AIMS: (i) Compare quantitative/semi-quantitatively MAdCAM-1 expression in relation to early and advanced liver diseases (ii) Define the fine structure of vascular plexuses/lymphatics in the portal tract on which MAdCAM-1 is expressed. METHODS: Using alkaline phosphatase anti-alkaline phosphatase methodology on paraffin embedded tissue sections (n=28) from cirrhotic individuals who underwent orthotopic liver transplant, we evaluated MAdCAM-1 expression and compared with pre-cirrhotic, fulminant hepatitis B, and non-cirrhotic portal hypertension tissue sections. The positive controls included normal colon tissue with negative controls without primary antibody and isotype-matched purified IgG. We developed a real time PCR to quantify levels of MAdCAM-1 mRNA in our samples. RESULTS: MAdCAM-1 was expressed in 27/28 of the cirrhotic sections, localized primarily to septal areas within (i) endothelium of the peribiliary vascular plexus (PBP) (ii) lymphoid aggregates, with absence from normal, non-cirrhotic portal hypertension and pre-cirrhotic livers. There was significant upregulation of MAdCAM-1 mRNA in cirrhosis (p<0.011), consistent with immunohistochemical analysis. CONCLUSIONS: MAdCAM-1 is up-regulated in cirrhosis with expression on PBP and lymphoid aggregates. MAdCAM-1 is likely to contribute to the localization and recruitment of α4ß7 lymphocytes during the pathogenesis of cirrhosis. MAdCAM-1 could be a useful marker of advanced liver disease. Further studies with respect to the expression of MAdCAM-1 in the presence of reversible and non-reversible stages of liver disease may be of merit.


Assuntos
Imunoglobulinas/metabolismo , Cirrose Hepática/metabolismo , Fígado/metabolismo , Mucoproteínas/metabolismo , Adulto , Moléculas de Adesão Celular , Colo/metabolismo , Endotélio Linfático/metabolismo , Feminino , Humanos , Imuno-Histoquímica , Fígado/irrigação sanguínea , Tecido Linfoide/metabolismo , Masculino , Pessoa de Meia-Idade , RNA Mensageiro/metabolismo , Adulto Jovem
6.
Med Confl Surviv ; 33(4): 323-325, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-29219618
10.
Clin Med (Lond) ; 10(4): 330-5, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20849004

RESUMO

The European Working Time Directive (EWTD) has resulted in large changes in the working patterns of junior doctors in the U.K. All consultant physicians in England and Wales were invited to anonymously submit data on their teams for 11 am and 11 pm on 5 November 2009. Data on doctor number, grade, location and patient number were collected. Data were available on 887 hospital teams at 11 am and on 670 teams at 11 pm. At 11 am, the average number of patients per ward doctor was 11 (2-65). At 11 pm the average number of patients per doctor was 61 (1-400). Consultants were present overnight in 6.1% of teams. Doctors in the first two years of training were the most senior medical cover in 63 teams. Sickness rates varied between 1.5% and 3.5% for junior doctors, and were significantly higher in the second foundation year. Vacancy rates at the specialist registrar level were 8.6%. Trainees were available for training 66-80% of the time. These findings have significant implications for patient safety and quality of medical training in the U.K.


Assuntos
Internato e Residência/organização & administração , Corpo Clínico Hospitalar/provisão & distribuição , Admissão e Escalonamento de Pessoal/organização & administração , Carga de Trabalho/estatística & dados numéricos , Continuidade da Assistência ao Paciente , Educação de Pós-Graduação em Medicina , Inglaterra , Humanos , Internato e Residência/legislação & jurisprudência , Admissão e Escalonamento de Pessoal/legislação & jurisprudência , Qualidade da Assistência à Saúde , Licença Médica/estatística & dados numéricos , País de Gales
11.
Bioconjug Chem ; 20(2): 266-73, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19140729

RESUMO

We present a labeling system for direct chemiluminescence-based cellular bioassays using the stable pro-chemiluminescent, luminol precursor, 3-aminophthalimide (API). API-coupled reporter molecules are detected chemiluminometrically after treatment with hydrazine, which converts the API label to luminol. API derivatives containing a variety of functional groups are readily synthesized, allowing for ease of coupling via the imide nitrogen to a host of reporter molecules. The fluorescent nature of APIs further allows for dual fluorescence and chemiluminescence studies. To highlight the utility of this label, we show that API-labeled insulin can be successfully utilized in cellular binding and transport assays and that an API-coupled mitochondrial probe (API-triphenylphosphonium(+)) can be used to both fluorescently and chemiluminometrically investigate mitochondrial function. We also assess the use of API as a polysaccharide and nucleic acid label, and we show that API-labeled palmitic acid undergoes cellular transport and lipid metabolism.


Assuntos
Fluorescência , Ftalimidas/química , Coloração e Rotulagem/métodos , Animais , Bioensaio , Linhagem Celular Tumoral , Fluoresceínas/química , Fluoresceínas/metabolismo , Heparina/química , Heparina/metabolismo , Humanos , Hidrazinas/química , Insulina/química , Insulina/metabolismo , Metabolismo dos Lipídeos , Lipídeos/química , Microscopia de Fluorescência , Mitocôndrias/metabolismo , Ácidos Nucleicos/química , Ácidos Nucleicos/metabolismo , Ácido Palmítico/síntese química , Ácido Palmítico/química , Ftalimidas/síntese química , Ftalimidas/metabolismo
12.
Artif Organs ; 33(6): 425-30, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19473137

RESUMO

The aim of the study was to determine if thyroid hormone-induced liver cell proliferation occurs through the Bcl-3 proto-oncogene. Rodents (including Bcl-3 knockout mice and the wild-type strain) were injected with a single dose of tri-iodothyronine (T(3)) and sacrificed at various time points. Hepatic mRNA (real-time polymerase chain reaction ) and protein expression (Western analysis) of Bcl-3 was quantified in rats stimulated with T(3). Cell proliferation was induced in a variety of cell types after T(3) injection at 24 h including hepatocytes (7 +/- 1.1% vs. 0.45 +/- 0.025%; P < 0.01), hepatic nonparenchymal cells (3.8 +/- 1.2% vs. 0.3 +/- 0.01%; P < 0.01), renal tubular cells (8.1 +/- 1.6% vs. 0.2 +/- 0.035%; P < 0.01), and splenic lymphocytes (4.8 +/- 1.2% vs. 0.35 +/- 0.02%; P < 0.01). We showed a twofold increase in hepatic Bcl-3 mRNA (P < 0.01) and protein expression (P < 0.01) at 24 h in rats stimulated with T(3). However, there were no differences in the rate of liver cell proliferation between Bcl-3 knockout mice and the wild-type strain (0.4 +/- 0.15% vs. 0.3 +/- 0.1%), indicating that Bcl-3 was not functionally involved in thyroid hormone-induced liver cell proliferation. A single gene is unlikely to initiate the process of thyroid hormone-induced cell proliferation. A complex interaction between the genomic and nongenomic effects of thyroid hormone is likely to regulate the mitogenic effects.


Assuntos
Proliferação de Células/efeitos dos fármacos , Fígado/citologia , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Tri-Iodotironina/farmacologia , Animais , Proteína 3 do Linfoma de Células B , Regulação da Expressão Gênica , Fígado/metabolismo , Camundongos , Camundongos Knockout , RNA Mensageiro/genética , Ratos , Ratos Sprague-Dawley
13.
Artif Organs ; 33(12): 1117-26, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20078562

RESUMO

Alginate-encapsulated HepG2 cells cultured in microgravity have the potential to serve as the cellular component of a bioartificial liver. This study investigates their performance in normal and liver failure (LF) human plasma over 6-8 h in a fluidized bed bioreactor. After 8 days of microgravity culture, beads containing 1.5 x 10(9) cells were perfused for up to 8 h at 48 mL/min with 300 mL of plasma. After exposure to 90% LF plasma, vital dye staining showed maintained cell viability, while a 7% increase in lactate dehydrogenase activity indicated minimal cell damage. Glucose consumption, lactate production, and a 4.3-fold linear increase in alpha-fetoprotein levels were observed. Detoxificatory function was demonstrated by quantification of bilirubin conjugation, urea synthesis, and Cyp450 1A activity. These data show that in LF plasma, alginate-encapsulated HepG2 cells can maintain viability, and metabolic, synthetic, and detoxificatory activities, indicating that the system can be scaled-up to form the biological component of a bioartificial liver.


Assuntos
Alginatos/química , Reatores Biológicos , Células Hep G2/metabolismo , Falência Hepática/terapia , Fígado Artificial , Plasma/metabolismo , Albuminas/metabolismo , Amônia/metabolismo , Bilirrubina/metabolismo , Sobrevivência Celular , Terapia Baseada em Transplante de Células e Tecidos/métodos , Células Imobilizadas/citologia , Células Imobilizadas/metabolismo , Glucose/metabolismo , Ácido Glucurônico/química , Células Hep G2/citologia , Ácidos Hexurônicos/química , Humanos , L-Lactato Desidrogenase/metabolismo , Transaminases/metabolismo
16.
Clin Med (Lond) ; 14(4): 333, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25099827
18.
Biotechnol Bioeng ; 99(3): 644-51, 2008 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-17680661

RESUMO

Extrahepatic bioartificial liver devices should provide an intact urea cycle to detoxify ammonia. The C3A cell line, a subclone of the hepatoma-derived HepG2 cell line, is currently used in this context as it produces urea, and this has been assumed to be reflective of ammonia detoxification via a functional urea cycle. However, based on our previous findings of perturbed urea-cycle function in the non-urea producing HepG2 cell line, we hypothesized that the urea produced by C3A cells was via a urea cycle-independent mechanism, namely, due to arginase II activity, and therefore would not detoxify ammonia. Urea was quantified using (15)N-ammonium chloride metabolic labelling with gas chromatography-mass spectrometry. Gene expression was determined by real-time reverse transcriptase-PCR, protein expression by western blotting, and functional activities with radiolabelling enzyme assays. Arginase inhibition studies used N(omega)-hydroxy-nor-L-arginine. Urea was detected in C3A conditioned medium; however, (15)N-ammonium chloride-labelling indicated that (15)N-ammonia was not incorporated into (15)N-labelled urea. Further, gene expression of two urea cycle genes, ornithine transcarbamylase and arginase I, were completely absent. In contrast, arginase II mRNA and protein was expressed at high levels in C3A cells and was inhibited by N(omega)-hydroxy-nor-L-arginine, which prevented urea production, thereby indicating a urea cycle-independent pathway. The urea cycle is non-functional in C3A cells, and their urea production is solely due to the presence of arginase II, which therefore cannot provide ammonia detoxification in a bioartificial liver system. This emphasizes the continued requirement for developing a component capable of a full repertoire of liver function.


Assuntos
Amônia/metabolismo , Carcinoma Hepatocelular/metabolismo , Técnicas de Cultura de Células/métodos , Fígado Artificial , Engenharia Tecidual/métodos , Ureia/metabolismo , Linhagem Celular Tumoral , Humanos
19.
J Gastroenterol Hepatol ; 23(12): 1926-33, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18717759

RESUMO

BACKGROUND AND AIM: A single dose of the thyroid hormone tri-iodothyronine, T3, can enhance both size and function of normal rodent liver, which is potentially of value in the treatment of liver disease. However the mechanism of this has not been fully elucidated, and it cannot be modeled in vitro. We therefore investigated the transcriptome response to T3 in rat liver in vivo. METHODS: After adult rats were administered 5 microg T3 subcutaneously, a whole rat genome microarray comparing global hepatic gene expression against vehicle-only treated liver after 3 h was performed. RESULTS: Informative transcripts which had identifiable gene ontology biological processes were grouped according to function, broadly reflecting general metabolic effects and those linked to cell-proliferation control. We then compared the transcriptome response after 5-microg T3 initiating hepatocyte DNA synthesis (mitogenic) with that after 0.1 microg T3, a supraphysiological amount not initiating hepatocyte DNA synthesis. CONCLUSIONS: We compared the results with published results of the response to other primary mitogens, and identified the Gadd45beta/MyD118 gene as a common early factor upregulated during proliferation.


Assuntos
Proliferação de Células , Replicação do DNA , Perfilação da Expressão Gênica/métodos , Substâncias de Crescimento/metabolismo , Fígado/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , Tri-Iodotironina/metabolismo , Animais , Antígenos de Diferenciação/genética , Ciclina D1/genética , Bases de Dados Genéticas , Substâncias de Crescimento/administração & dosagem , Injeções Subcutâneas , RNA/metabolismo , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Tempo , Tri-Iodotironina/administração & dosagem
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