Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 48
Filtrar
1.
Am J Transplant ; 18(2): 321-327, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29194964

RESUMO

The science of regenerative medicine is arguably older than transplantation-the first major textbook was published in 1901-and a major regenerative medicine meeting took place in 1988, three years before the first Banff transplant pathology meeting. However, the subject of regenerative medicine/tissue engineering pathology has never received focused attention. Defining and classifying tissue engineering pathology is long overdue. In the next decades, the field of transplantation will enlarge at least tenfold, through a hybrid of tissue engineering combined with existing approaches to lessening the organ shortage. Gradually, transplantation pathologists will become tissue-(re-) engineering pathologists with enhanced skill sets to address concerns involving the use of bioengineered organs. We outline ways of categorizing abnormalities in tissue-engineered organs through traditional light microscopy or other modalities including biomarkers. We propose creating a new Banff classification of tissue engineering pathology to standardize and assess de novo bioengineered solid organs transplantable success in vivo. We recommend constructing a framework for a classification of tissue engineering pathology now with interdisciplinary consensus discussions to further develop and finalize the classification at future Banff Transplant Pathology meetings, in collaboration with the human cell atlas project. A possible nosology of pathologic abnormalities in tissue-engineered organs is suggested.


Assuntos
Rejeição de Enxerto/patologia , Transplante de Rim , Rim/patologia , Patologia Clínica/normas , Medicina Regenerativa , Engenharia Tecidual , Rejeição de Enxerto/classificação , Humanos
2.
Artigo em Inglês | MEDLINE | ID: mdl-28167552

RESUMO

Despite its toxicity and low efficacy in the chronic phase, benznidazole is the drug of choice in Chagas disease. Scarce information about pharmacokinetics and pharmacodynamics of benznidazole has been published. We performed a phase I, open-label, nonrandomized pharmacokinetic study of benznidazole (Abarax) conducted with 8 healthy adult volunteers at the Infectious Diseases Department of the Vall d'Hebron University Hospital (Barcelona, Spain). The separation and detection of benznidazole were performed on a Waters Acquity ultraperformance liquid chromatography system (UPLC) coupled with a Waters Xevo TQ MS triple quadrupole mass spectrometer. The pharmacokinetic parameters were calculated based on a noncompartmental body model using Phoenix WinNonlin version 6.3 software. Furthermore, computational simulations were calculated for the multiple-dose administration at two dose regimens: 100 mg of benznidazole administered every 8 h and 150 mg of benznidazole administered every 12 h. After benznidazole administration, the median area under the concentration-time curve from time zero to time t (AUC0-t ) and extrapolated to infinity (AUC0-∞) were about 46.4 µg · h/ml and 48.4 µg · h/ml, respectively. Plasma benznidazole concentrations peaked at 3.5 h, with maximal concentrations of 2.2 µg/ml, and benznidazole exhibited a terminal half-life of 12.1 h. The median maximum concentration (Cmax) of benznidazole was lower in men than in women (1.6 versus 2.9 µg/ml), and median volume of distribution (V) as a function of bioavailability (F) was higher in men than in women (125.9 versus 88.6 liters). In conclusion, dose regimens (150 mg/12 h or 100 mg/8 h) reached a steady-state range concentration above of the minimum experimental therapeutic dose. Sex differences in the benznidazole pharmacokinetics were observed; mainly, men had lower Cmax and higher V/F than women.


Assuntos
Modelos Estatísticos , Nitroimidazóis/farmacocinética , Tripanossomicidas/farmacocinética , Adolescente , Adulto , Área Sob a Curva , Disponibilidade Biológica , Índice de Massa Corporal , Doença de Chagas/tratamento farmacológico , Doença de Chagas/parasitologia , Esquema de Medicação , Cálculos da Dosagem de Medicamento , Feminino , Meia-Vida , Voluntários Saudáveis , Humanos , Masculino , Nitroimidazóis/sangue , Tripanossomicidas/sangue
3.
J Appl Microbiol ; 113(2): 318-28, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22587647

RESUMO

AIMS: To provide molecular and phenotypical characterization of Enterococcus isolates obtained from raw milk and cheese, regarding their bacteriocinogenic and virulence activity. METHODS AND RESULTS: Forty-three bacteriocinogenic enterococci isolates were identified by 16s rDNA, fingerprinted by RAPD-PCR analysis and tested by PCR for the presence of genes for lantibiotics (lanM, lanB and lanC) and enterocins (entA, entB, entP, entL50AB and entAS48) and by phenotypical methods for bacteriocin production and inhibitory spectrum. Also, the virulence of the isolates was evaluated by PCR for genes gelE, hyl, asa1, esp, cylA, efaA, ace, vanA, vanB, hdc1, hdc2, tdc and odc and by phenotypical tests for gelatinase, lipase, DNAse and α- and ß-haemolysis. Most isolates (93·0%) harboured at least one lantibiotic or enterocin gene and were positive for several tested virulence genes, mainly asa1 (100%), gelE (93·0%) and efaA (83.7%). 53.5% of the isolates presented ß-haemolysis [corrected]. CONCLUSIONS: Enterococcus spp. isolates presented an interesting potential application for food preservation because of bacteriocin production; however, virulence-related genes were identified in all RAPD profiles. SIGNIFICANCE AND IMPACT OF THE STUDY: The study demonstrated the contradictory characteristics of the tested Enterococcus isolates: they presented a good potential for application in food biopreservation but contained several virulence factors.


Assuntos
Queijo/microbiologia , Enterococcus/classificação , Enterococcus/patogenicidade , Leite/microbiologia , Animais , Bacteriocinas/genética , Enterococcus/genética , Enterococcus/isolamento & purificação , Genes Bacterianos , RNA Ribossômico 16S/genética , Técnica de Amplificação ao Acaso de DNA Polimórfico , Virulência
4.
J Dairy Sci ; 93(7): 2880-6, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20630205

RESUMO

Lactic acid bacteria (LAB) are currently used by food industries because of their ability to produce metabolites with antimicrobial activity against gram-positive pathogens and spoilage microorganisms. The objectives of this study were to identify naturally occurring bacteriocinogenic or bacteriocinogenic-like LAB in raw milk and soft cheese and to detect the presence of nisin-coding genes in cultures identified as Lactococcus lactis. Lactic acid bacteria cultures were isolated from 389 raw milk and soft cheese samples and were later characterized for the production of antimicrobial substances against Listeria monocytogenes. Of these, 58 (14.9%) LAB cultures were identified as antagonistic; the nature of this antagonistic activity was then characterized via enzymatic tests to confirm the proteinaceous nature of the antimicrobial substances. In addition, 20 of these antagonistic cultures were selected and submitted to genetic sequencing; they were identified as Lactobacillus plantarum (n=2) and Lactococcus lactis ssp. lactis (n=18). Nisin genes were identified by polymerase chain reaction in 7 of these cultures. The identified bacteriocinogenic and bacteriocinogenic-like cultures were highly variable concerning the production and activity of antimicrobial substances, even when they were genetically similar. The obtained results indicated the need for molecular and phenotypic methodologies to properly characterize bacteriocinogenic LAB, as well as the potential use of these cultures as tools to provide food safety.


Assuntos
Bacteriocinas/genética , Bacteriocinas/metabolismo , Queijo/microbiologia , Microbiologia de Alimentos , Leite/microbiologia , Animais , Anti-Infecciosos/isolamento & purificação , Anti-Infecciosos/farmacologia , Bacteriocinas/análise , Lactobacillus plantarum/isolamento & purificação , Lactobacillus plantarum/metabolismo , Lactococcus lactis/química , Lactococcus lactis/genética , Listeria monocytogenes/efeitos dos fármacos , Nisina/genética
5.
Sci Rep ; 7(1): 16875, 2017 12 04.
Artigo em Inglês | MEDLINE | ID: mdl-29203902

RESUMO

Injection of amniotic fluid stem cells (AFSC) delays the course of progression of renal fibrosis in animals with Alport Syndrome, enhancing kidney function and improving survival. The mechanisms responsible for these protective outcomes are still largely unknown. Here, we showed that vascular endothelial growth factor (VEGF) signaling within the glomeruli of Alport mice is strongly elevated early on in the disease, causing glomerular endothelial cell damage. Intraventricular injected AFSC that homed within the glomeruli showed strong modulation of the VEGF activity, particularly in glomerular endothelial cells. To investigate this phenomenon we hypothesized that extracellular vesicles (EVs) produced by the AFSC could be responsible for the observed renoprotection. AFSC derived EVs presented exosomal and stem cell markers on their surface membrane, including VEGFR1 and VEGFR2. EVs were able to modulate VEGF in glomerular endothelial cells by effectively trapping the excess VEGF through VEGFR1-binding preventing cellular damage. In contrast, VEGFR1/sVEGFR1 knockout EVs failed to show similar protection, thus indicating that VEGF trapping is a potentially viable mechanism for AFSC-EV mediated renoprotection. Taken together, our findings establish that EVs secreted by AFSC could target a specific signaling pathway within the glomerulus, thus representing a new potential glomerulus-specific targeted intervention.


Assuntos
Células Endoteliais/metabolismo , Vesículas Extracelulares , Células-Tronco/metabolismo , Líquido Amniótico/citologia , Animais , Células Cultivadas , Técnicas de Cocultura , Creatinina/sangue , Modelos Animais de Doenças , Células Endoteliais/citologia , Células Endoteliais/efeitos dos fármacos , Vesículas Extracelulares/metabolismo , Glomérulos Renais/citologia , Camundongos , Nefrite Hereditária/metabolismo , Nefrite Hereditária/patologia , Proteinúria/patologia , Transdução de Sinais , Células-Tronco/citologia , Fator A de Crescimento do Endotélio Vascular/farmacologia , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo
6.
Endocrinology ; 141(7): 2557-66, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10875258

RESUMO

The insulin-like growth factor (IGF) system is a major regulator of somatic growth in vertebrates. Both ligands (IGF-I and IGF-II) signal via the same IGF receptor (IGF-IR). Classical IGF-IR invalidation is lethal at birth, so that conditional models are needed to study the postnatal role of this receptor. To establish a genetically inducible invalidation of IGF-IR, we targeted the IGF-IR gene using a construct that introduced a neomycin resistance cassette into intron 2, leaving the rest of the gene intact. This neomycin resistance cassette interfered with the processing of the primary transcript, resulting in there being 12% fewer IGF-binding sites at the cell surface in heterozygous mice and 41% fewer in homozygous mice. Hetero- and homozygous offspring grew more slowly than their wild-type littermates. This difference was noticeable from 4 weeks after birth and was significant from 5 weeks after birth in males. In females, the effect on postnatal growth of insertion of the neo cassette was not significant. In males, IGF-I levels increased moderately (+26%) but significantly, indicating effective feedback regulation of the IGF system. IGF-binding protein-4 (IGFBP-4) levels, estimated by Western ligand blotting, were low in homozygotes (-38%), whereas IGFBP-1, -2, and -3 levels were unaffected. In females, IGF-I and IGFBP-1, -2, -3, and -4 levels did not differ significantly among heterozygous, homozygous, and wild-type animals. We investigated the molecular mechanism involved and characterized two RNA-splicing events that could account for the decrease in IGF-IR. The phenotype of these mice developed exclusively postnatally, and body proportions were maintained. IGF-IRneo mice constitute a new model for human postnatal growth deficiency.


Assuntos
Animais Recém-Nascidos/genética , Marcação de Genes , Transtornos do Crescimento/genética , Splicing de RNA/genética , Receptor IGF Tipo 1/genética , Animais , Animais Recém-Nascidos/crescimento & desenvolvimento , Antibacterianos , Sequência de Bases/genética , Elementos de DNA Transponíveis , Evolução Molecular Direcionada , Resistência Microbiana a Medicamentos/genética , Feminino , Humanos , Íntrons/genética , Masculino , Camundongos , Dados de Sequência Molecular , Neomicina , Fenótipo , Somatomedinas/metabolismo
7.
Endocrinology ; 142(10): 4469-78, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11564712

RESUMO

Reduced IGF type I receptor levels diminish postnatal growth rate and adult body weight in mice. Here, we studied the impact of experimental IGF receptor deficiency on tissue-specific growth by Cre-lox-mediated dosage of a floxed IGF-IR gene. We generated mice with a wide spectrum of receptor deficiency (5-82%), and separated them into two groups with either strong (> or =50%) IGF-IR deficiency (XS mice) or moderate deficiency (<50%, M mice). The growth of XS mice was significantly retarded from 3 wk after birth onward, with respect to M littermates. This effect was twice as strong in males as in females. Growth deficits persisted throughout adult life, and at 10-12 months, most organs and tissues showed specific weight defects. Skin, bone and connective tissue, muscle, spleen, heart, lung, and brain were the most severely affected organs in the XS males. With the exception of muscle and spleen, the same tissues were also significantly reduced in size in females, although to a lesser extent. The most severe growth defect, however, concerned adipose tissue. Fat pad size in XS males was only 29% (females, 44%) of M mice. The estimated number of adipocytes in XS male fat pads was only 21% that of M males (XS female, 27%). Lipid content per cell was significantly higher in XS adipocytes, whereas plasma glucose and insulin levels were low in XS males. Thus, IGF type I receptor deficiency produced mice with disproportionate postnatal organ growth, and these effects depended strongly on sex. A marked reduction in IGF-IR levels resulted in a major defect in adipose tissue.


Assuntos
Transtornos do Crescimento/etiologia , Receptor IGF Tipo 1/deficiência , Animais , Feminino , Transtornos do Crescimento/genética , Transtornos do Crescimento/metabolismo , Masculino , Camundongos , Camundongos Transgênicos , Especificidade de Órgãos , Receptor IGF Tipo 1/genética , Caracteres Sexuais , Fatores Sexuais
8.
J Clin Endocrinol Metab ; 83(5): 1713-20, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-9589681

RESUMO

In adrenocortical tumors, malignancy is strongly associated with insulin-like growth factor II (IGF-II) gene overexpression and abnormalities at the 11p15 locus, suggesting a role for this growth factor in adrenocortical tumorigenesis. To further investigate this role, the IGF/IGF-binding protein (IGFBP) system was analyzed in 18 adrenocortical tumors, classified into 2 groups on the basis of their IGF-II messenger ribonucleic acid (mRNA) content (group 1, normal IGF-II mRNA content, mostly benign tumors; group 2, high IGF-II mRNA content, mostly malignant tumors). Group 2 tumors contained 10 times more IGF-II protein than group 1 tumors or normal adrenal tissue (P < 0.001), indicating efficient translation of IGF-II mRNA in malignant tumors. Western ligand blotting detected various functional IGFBPs in normal adrenocortical glands and tumors: a doublet of 39-42 kDa identified by immunoblotting as IGFBP-3, a band at 32 kDa, and bands at 29-30 and 24 kDa. Total IGFBP-3 protein levels were similar in the two groups of tumors. By contrast, malignant tumors differed from benign ones by specific expression of the 32-kDa IGFBP. Immunoblotting identified this 32-kDa band together with a proteolytic fragment of 25 kDa as IGFBP-2, and quantitative analysis showed significantly higher levels of total IGFBP-2 in malignant tumors than in benign tumors (P < 0.001). Despite enhanced levels of IGBP-2 protein in malignant tumors, no increase in IGFBP-2 mRNA levels was detected, suggesting post-transcriptional regulation of this IGFBP. These results confirm the major role of IGF-II in adrenocortical tumorigenesis and suggest that IGFBP-2 may be a regulator of IGF-II proliferative effects in this tumor system.


Assuntos
Neoplasias do Córtex Suprarrenal/metabolismo , Proteína 2 de Ligação a Fator de Crescimento Semelhante à Insulina/metabolismo , Fator de Crescimento Insulin-Like II/metabolismo , Adolescente , Neoplasias do Córtex Suprarrenal/química , Adulto , Idoso , Northern Blotting , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Immunoblotting , Proteína 2 de Ligação a Fator de Crescimento Semelhante à Insulina/análise , Proteína 2 de Ligação a Fator de Crescimento Semelhante à Insulina/genética , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/genética , Proteína 6 de Ligação a Fator de Crescimento Semelhante à Insulina/genética , Fator de Crescimento Insulin-Like II/análise , Fator de Crescimento Insulin-Like II/genética , Masculino , Pessoa de Meia-Idade , RNA Mensageiro/análise
9.
J Clin Endocrinol Metab ; 86(11): 5516-24, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11701730

RESUMO

The IGFs, IGF-I and IGF-II, regulate fetal growth by activating IGF type 1 receptors (IGF-IR). We aimed to quantify the binding of IGF-I to its cognate receptors in intrauterine growth-retarded children (IUGR). We measured the affinity of the erythrocyte IGF-IR and the number of IGF-IR receptors in 17 children with retarded growth (mean height, -2.7 SD), normal levels of GH, and a history of idiopathic intrauterine growth retardation (height at birth, -10 to -2 SD; mean, -3.1 SD). These children had reduced receptor affinity (Kd = 0.47 nM; P < 0.01) and more receptors per cell [binding capacity (Bmax) = 11.7 binding sites/cell; P < 0.05)] compared with control children (Kd = 0.32 nM; Bmax = 7.8 binding sites/cell). Moreover, the distributions of Kd and Bmax suggested that there were two groups of IUGR children. Group 1 included subjects with normal receptor binding function (Kd = 0.36 nM; Bmax = 8.2 sites/cell) and normal levels of circulating IGF-I. Group 2 comprised children with low receptor affinity (Kd = 0.56 nM) and increased receptor number (Bmax = 14.7 sites/cell). This group showed significantly decreased IGF-I levels (-2.1 SD; P < 0.01). We investigated these IGF-IR binding parameters in two additional groups of growth-retarded children (Turner syndrome and patients with chronic renal failure), in whom the IGF-I axis was not believed to be the primary cause, and found that Kd and Bmax were normal or nearly normal. We also measured IGF-IR binding parameters in 4 Seckel syndrome patients with IUGR and severely retarded growth (mean height, -7.9 SD). Their receptor affinity was reduced, but not statistically different, from that in controls, and their receptor number was normal, whereas IGF-I levels were elevated. Our results suggest heterogeneous alterations in IGF-IR binding function in IUGR patients.


Assuntos
Retardo do Crescimento Fetal/metabolismo , Receptor IGF Tipo 1/metabolismo , Adolescente , Criança , Pré-Escolar , Eritrócitos/metabolismo , Hormônio do Crescimento Humano/sangue , Humanos , Fator de Crescimento Insulin-Like I/metabolismo , Radioisótopos do Iodo , Cinética , Masculino , Radioimunoensaio
10.
J Mol Endocrinol ; 23(1): 23-32, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10425444

RESUMO

In adrenocortical tumors, the malignant phenotype is associated with rearrangements (paternal isodisomy) at the 11p15 locus and IGF-II gene overexpression, strongly suggesting that the IGF system is a major determinant of adrenocortical tumor progression. The aim of this study was to validate an in vitro model for investigating the involvement of the IGF system in adrenocortical tumorigenesis. We analyzed the production of IGF mRNA and proteins, IGF-binding proteins (IGFBPs) and IGF receptors by the NCI H295R cell line, which is derived from a human adult adrenocortical carcinoma. H295R cells were shown to proliferate for a long period (26 days) in the absence of serum or any added growth factor. Northern blot analyses showed high IGF-II mRNA contents in H295R cells. The cells secreted large amounts of IGF-II protein (14 ng/10(6) cells per 48 h) although no IGF-I protein was detected. Western ligand blot analyses of conditioned media detected the presence of large amounts of a 34 kDa protein, which was identified as IGFBP-2 by immunoblotting. The presence of high-affinity binding sites for IGF-I and IGF-II on H295R cells was shown by binding experiments using radiolabeled IGFs and confirmed by reverse transcription PCR analyses showing type 1 and type 2 IGF receptors. Proliferation of H295R cells was inhibited by anti-IGF-II antibody (45%) and by anti-type 1 IGF receptor antibody (53%) indicating that IGF-II is an autocrine growth factor for these cells and that its effects are, at least in part, mediated by the type 1 IGF receptor. These findings confirm the involvement of the IGF system in adrenocortical tumors and suggest that the H295R cell line is a suitable in vitro model for studying the molecular mechanisms of adrenocortical tumor proliferation.


Assuntos
Neoplasias do Córtex Suprarrenal/fisiopatologia , Carcinoma Adrenocortical/fisiopatologia , Divisão Celular/fisiologia , Fator de Crescimento Insulin-Like II/fisiologia , Neoplasias do Córtex Suprarrenal/genética , Neoplasias do Córtex Suprarrenal/patologia , Carcinoma Adrenocortical/genética , Carcinoma Adrenocortical/patologia , Ligação Competitiva , Meios de Cultura Livres de Soro/farmacologia , Humanos , Proteínas de Ligação a Fator de Crescimento Semelhante a Insulina/metabolismo , Fator de Crescimento Insulin-Like I/metabolismo , Fator de Crescimento Insulin-Like II/genética , Fator de Crescimento Insulin-Like II/metabolismo , Radioisótopos do Iodo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptor IGF Tipo 1/metabolismo , Células Tumorais Cultivadas/citologia , Células Tumorais Cultivadas/metabolismo
11.
Eur J Endocrinol ; 146(5): 657-65, 2002 May.
Artigo em Inglês | MEDLINE | ID: mdl-11980621

RESUMO

OBJECTIVE: To investigate the mechanisms determining the success or failure of refeeding therapy in malnourished elderly patients with inflammation by studying changes in plasma IGF-I, GH-binding protein (GHBP) and IGF-binding protein (IGFBP) levels and IGFBP-3 proteolysis. DESIGN AND METHODS: We studied 15 severely malnourished hospitalized elderly patients. Weight, food intake, plasma albumin, transthyretin, C-reactive protein (CRP), orosomucoid, interleukin-6 (IL-6), IGF-I, intact and proteolytically degraded IGFBP-3 and GHBP levels were determined on admission and during refeeding therapy designed to increase food intake to 40 kcal/kg body weight per day (15% protein). RESULTS: Plasma IGF-I, IGFBP-3 and GHBP levels were significantly low for age on admission in all malnourished elderly patients. They increased in nine patients as nutritional status improved (albuminemia >30 g/l; transthyretinemia >200 mg/l or weight gain >5% of initial body weight) and levels of inflammation markers decreased (group 1). In contrast, plasma IGF-I, IGFBP-3 and GHBP levels remained low in six patients in whom nutritional status failed to improve and levels of inflammation markers increased (group 2). IGF-I showed greater variations than IGFBP-3 or GHBP with respect to nutritional status. High plasma CRP and IL-6 levels were associated with high levels of IGFBP-3 proteolysis. CONCLUSION: Efficient refeeding therapy was associated with a significant increase in IGF-I plasma levels. In patients with severe and persistent inflammation, high levels of proteolysis of IGFBP-3 may have contributed to the low plasma IGF-I levels, persistence of hypercatabolism and lack of improvement in nutritional status.


Assuntos
Proteínas de Transporte/sangue , Alimentos , Inflamação/complicações , Proteínas de Ligação a Fator de Crescimento Semelhante a Insulina/sangue , Fator de Crescimento Insulin-Like I/análise , Distúrbios Nutricionais/sangue , Distúrbios Nutricionais/complicações , Idoso , Idoso de 80 Anos ou mais , Proteína C-Reativa/análise , Feminino , Humanos , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/metabolismo , Interleucina-6/sangue , Masculino , Distúrbios Nutricionais/fisiopatologia , Distúrbios Nutricionais/terapia , Estado Nutricional , Peptídeo Hidrolases/metabolismo
12.
Eur J Endocrinol ; 137(5): 467-73, 1997 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9405025

RESUMO

We investigated the expression and potential regulatory role of insulin-like growth factors (IGFs) and their specific binding proteins (BPs) in tuberculous and nontuberculous pleuritis. By using a radioimmunoassay after acid gel filtration chromatography, we found that mean concentrations of IGF-I were 211.9 +/- 20.2 microg/l and 203.2 +/- 31.1 microg/l in pleural fluid of 14 patients with tuberculous pleuritis and 9 patients with malignant pleuritis respectively. These values were near those in serum of the same patients (221.3 +/- 19.5 microg/l and 204.6 +/- 21.0 microg/l respectively). By using a specific protein-binding assay, we found that mean concentrations of IGF-II were 345.3 +/- 61.0 microg/l and 167.6 +/- 22.7 microg/l in tuberculous and malignant pleural effusions respectively. These values were significantly lower than those in serum of the same patients (628.3 +/- 79.0 microg/l, P<0.025 and 532.0 +/- 85.9 microg/l, P<0.025 respectively). Because bioavailability and bioactivity of IGFs may be regulated by their binding to IGFBPs, we studied IGFBP patterns in the pleural fluid of 6 patients with tuberculous pleuritis. As assessed by Western ligand blotting the levels of IGFBP-1 and IGFBP-2 were increased whereas those of IGFBP-3 were decreased in pleural fluid in comparison with serum. The decrease in IGFPB-3 levels reflected increased proteolysis, as assessed by Western immunoblotting. In spite of this presence of IGFBPs, IGFs could be responsible for the local biosynthesis of 1.25-dihydroxyvitamin D (1,25-(OH)2D) since pleural fluid levels of both IGF-I and IGF-II significantly correlated with those of 1,25-(OH)2D. These results indicate that IGFs are detectable in pleural fluid and may contribute to control the activity of 25-hydroxyvitamin D-1alpha hydroxylase in tuberculous pleuritis.


Assuntos
Líquidos Corporais/metabolismo , Proteínas de Ligação a Fator de Crescimento Semelhante a Insulina/metabolismo , Fator de Crescimento Insulin-Like II/metabolismo , Fator de Crescimento Insulin-Like I/metabolismo , Pleura/metabolismo , Pleurisia/microbiologia , Pleurisia/fisiopatologia , Tuberculose , Adulto , Humanos , Fator de Crescimento Insulin-Like I/fisiologia , Fator de Crescimento Insulin-Like II/fisiologia
13.
Growth Horm IGF Res ; 10(6): 332-41, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11161964

RESUMO

Chronic renal failure in childhood causes severe growth retardation. The aim of the study was to identify whether changes in the IGF system could account for the growth retardation observed in children with chronic renal failure. Insulin-like growth factor (IGF-I) serum concentrations, insulin-like growth factor binding proteins (IGFBP) and/or IGF-I binding to erythrocyte type I receptor of IGF were analysed in 69 children (mean age 11.6 +/- 4.3 years) with chronic renal failure and growth retardation (mean height -2.6 +/- 1.8 SD). The study population was separated into three groups, according to their renal status, children on conservative treatment (CRF group: n = 30), on haemodialysis (ESRD group: n = 26) and those transplanted (RT group: n = 13). Nineteen of these children, some from each of the three groups, received recombinant growth hormone therapy (rhGH). Mean basal IGF-I serum concentrations were -0.7 +/- 1.2 SD in the CRF group, + 2.1 +/- 3 SD in the ESRD group and + 1.1 +/- 2 SD in the RT group. Under rhGH therapy, as height velocity improved, mean IGF-I concentrations increased up to + 3.1 +/- 0.6 SD in the CRF group, to + 6.9 +/- 2.8 SD in the ESRD group and to + 3.9 +/- 2 SD in the RT group. Basal IGFBP-3 levels, studied by Western Ligand Blot were low in the CRF group and high in the ESRD and normal in the RT groups, whereas IGFBP-2 and a 30-32 kDa IGFBP were always high in all cases. Western immunoblot analysis showed that this 30-32 kDa IGFBP was mostly composed of IGFBP-1 and IGFBP-6 in all three groups, but IGFBP-6 was particularly abundant in the ESRD group. IGFBP-6 concentrations assessed by RIA were moderately increased in CRF children (392 +/- 177 ng/mL) and very high in children on ESRD (2094 +/- 1525 ng/mL) when compared to normal values (131 +/- 42 ng/mL). Binding studies of IGF type I receptor showed that there was no particular difference in IGF-I binding between renal failure patients and normal children. In poorly growing children, especially in ESRD children and to a lesser extent in RT children, high concentrations of IGF-I and IGFBP-1, 2, 3 and 6, suggest a resistance mainly by a sequestration mechanism. Moreover, in the CRF group, especially in the younger children, low levels of IGF-I and IGFBP-3 are evocative of an associated resistance at the GH receptor level.


Assuntos
Proteínas de Ligação a Fator de Crescimento Semelhante a Insulina/sangue , Fator de Crescimento Insulin-Like I/metabolismo , Falência Renal Crônica/sangue , Receptor IGF Tipo 1/sangue , Adolescente , Western Blotting , Criança , Pré-Escolar , Eritrócitos/metabolismo , Feminino , Hormônio do Crescimento Humano/uso terapêutico , Humanos , Immunoblotting , Proteína 1 de Ligação a Fator de Crescimento Semelhante à Insulina/sangue , Proteína 2 de Ligação a Fator de Crescimento Semelhante à Insulina/sangue , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/sangue , Proteína 6 de Ligação a Fator de Crescimento Semelhante à Insulina/sangue , Falência Renal Crônica/tratamento farmacológico , Ligantes , Masculino , Ligação Proteica , Radioimunoensaio , Proteínas Recombinantes/uso terapêutico
14.
Nucl Med Biol ; 21(3): 297-302, 1994 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9234296

RESUMO

Insulin-like growth factors (IGFs), initially known as somatomedins, and their specific, high-affinity binding proteins (IGFBPs) are synthesized in most tissues, but principally in the liver. The interest of measuring their circulating levels, which reflect liver production, is to obtain indications as to their endocrine function and regulation. IGF-I plays a pivotal role in post-natal growth. Its half-life is significantly increased by its association with IGFBPs and its serum levels reflect somatotropic status, unlike growth hormone (GH) which has a much shorter half-life and whose secretion comes in pulses. Since investigation of growth retardation must include the most finely tuned appreciation possible of somatotropic secretion, assays of IFG-I and electrophoretic analysis of IGFBP profile can be useful tools, both diagnostically and therapeutically, and can help in determining the need or otherwise for GH treatment, especially in view of the growing demand for such therapy.


Assuntos
Proteínas de Ligação a Fator de Crescimento Semelhante a Insulina/metabolismo , Somatomedinas/metabolismo , Transtornos do Crescimento/tratamento farmacológico , Transtornos do Crescimento/metabolismo , Meia-Vida , Hormônio do Crescimento Humano/uso terapêutico , Humanos , Proteínas de Ligação a Fator de Crescimento Semelhante a Insulina/biossíntese , Fígado/metabolismo , Taxa Secretória , Somatomedinas/biossíntese
15.
Food Chem Toxicol ; 30(9): 789-94, 1992 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-1427517

RESUMO

Paraquat (PQ) is a widely used herbicide that causes acute adult respiratory distress syndrome (ARDS) and chronic lung damage (diffuse fibrosis). One of the earliest biochemical effects induced by PQ is damage to type II pneumocytes with consequent depletion of surfactant. With the aim of counteracting the toxic effects of PQ, a series of investigations were performed into the possible protective effect of the drug ambroxol, which induces the synthesis of surfactant in lung alveolar type II cells. The number of survivors and survival time of rats treated ip with 35 mg PQ/kg was significantly increased by 3 days of ambroxol pretreatment and by ambroxol treatment 30 min or 2 hr after PQ. Total phospholipid content in lung and bronchoalveolar lavage fluid (BALF) was significantly reduced 30 hr after treatment with PQ alone. The association of ambroxol with PQ significantly antagonized this reduction. In BALF the ratio between palmitic acid and stearic acid concentrations was significantly lower in animals treated with PQ alone but was returned to normal by the association with ambroxol. The cell line A549, exposed in vitro to PQ concentrations from 0.5 x 10(-4) to 2 x 10(-3) M, showed a significant dose-dependent loss of viability. Cells pretreated with ambroxol (10 mg/ml) were more resistant to PQ and their viability started to decrease significantly only from a PQ concentration of 0.8 x 10(-3) M. Membrane microviscosity was measured on the same cells. Cells treated with PQ alone showed a reduction of membrane microviscosity, which was significantly counteracted by ambroxol pretreatment. The curves of modification of membrane microviscosity of cells treated with PQ and with ambroxol plus PQ paralleled those of cell viability, indicating that the stimulation of surfactant synthesis in vitro may be a prerequisite for counteracting some of the early effects of PQ.


Assuntos
Ambroxol/uso terapêutico , Paraquat/intoxicação , Surfactantes Pulmonares/biossíntese , Adenocarcinoma , Animais , Líquido da Lavagem Broncoalveolar/química , Membrana Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Humanos , Dose Letal Mediana , Pulmão/química , Pulmão/efeitos dos fármacos , Neoplasias Pulmonares , Masculino , Paraquat/toxicidade , Fosfolipídeos/análise , Intoxicação/prevenção & controle , Proteínas/análise , Ratos , Células Tumorais Cultivadas , Viscosidade/efeitos dos fármacos
16.
Int Surg ; 72(1): 45-7, 1987.
Artigo em Inglês | MEDLINE | ID: mdl-3596978

RESUMO

Twenty-five patients with congenital uterovaginal agenesis underwent neovaginoplasty according to the McIndoe and Banister technique. In 17 (68.0%) cases the congenital agensis was also associated with renal and bone malformations. The postoperative results, based on the length of the neovagina, were considered to be satisfactory in 16 (64.0%) cases, moderate in five (20.0%) and fair in four (16.0%). Dehiscences, fistulae and retention cysts were observed in six (24.0%) cases but had no statistically significant correlation with the final length of the neovagina. On the other hand, a statistically significant relationship between the length of the neovagina and dyspareunia was observed.


Assuntos
Genitália Feminina/anormalidades , Vagina/cirurgia , Adolescente , Adulto , Feminino , Humanos , Pessoa de Meia-Idade , Síndrome
17.
Manag Care ; 9(9): 49-52, 54, 56-7 passim, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11116663

RESUMO

UNLABELLED: Pneumococcal disease is a common cause of morbidity and mortality in the pediatric population. Pneumococcal infections, which account for most serious bacterial disease in infancy and early childhood, are a major cause of acute otitis media, sinusitis, pneumonia, bacterial meningitis, and bacteremia. Streptococcus pneumoniae is the causative agent in a large percentage of these infections, although other microorganisms also play a role. The recent emergence of drug-resistant strains has provided a strong incentive for preventing pneumococcal infections by vaccination. However, the capsular polysaccharide pneumococcal vaccines used to immunize adults are neither immunogenic nor protective in young children due to poor antibody responses. Therefore, research has focused on development of additional immunogenic pneumococcal vaccines to provide long-term immunity in children < 2 years of age. The most promising approach has been the development of a protein-polysaccharide conjugate vaccine for the seven serotypes (4, 6B, 9V, 14, 18C, 19F, and 23F) that most commonly cause infections in childhood. An effective conjugate vaccine that protects against these serotypes has the potential to prevent 85 percent of bacteremia episodes, 83 percent of meningitis episodes, and 65 percent of otitis media cases in the U.S. among children younger than 6 years. The Food and Drug Administration (FDA) recently approved the first protein-polysaccharide conjugate vaccine to prevent invasive pneumococcal diseases in infants and toddlers < 2 years of age. This conjugated vaccine against pneumococcus uses the same technology as the successful vaccine against Haemophilus influenzae type b. It consists of an immunogenic but inert protein coupled covalently to the polysaccharide coat of the selected strains of pneumococci. The conjugated antigen induces a more powerful, T-cell-based immune response in infants, which is developed by the time they are 2 months of age. Some important questions regarding this vaccine for children < 2 years of age: Is the vaccine safe? Is it immunogenic? Is it efficacious in preventing invasive pneumococcal disease and controlling otitis media? FINDINGS: Results of three randomized double-blind trials designed to evaluate the safety and immunogenicity of this vaccine in healthy children < 2 years of age were reported within the last three years. The studies found that the vaccine is safe and highly immunogenic for all seven serotypes. The most recent study, involving over 37,000 young children, also evaluated the vaccine's efficacy, and reported that the vaccine is highly effective in preventing invasive disease and has had an impact on otitis media. CONCLUSIONS: The heptavalent pneumococcal conjugate vaccine is safe and highly effective in preventing pneumococcal meningitis and bacteremic pneumonia in young children < 2 years of age; it is less effective in preventing otitis media. Based on the results of three well-designed studies demonstrating the vaccine's safety, immunogenicity, and efficacy, the vaccine is safe and effective for active immunization of children < 2 years of age against invasive disease caused by seven Streptococcus pneumoniae serotypes included in the vaccine. At this time, there is no clear medical consensus regarding its safety and efficacy for control of otitis media in children < 2 years of age. This application has not been evaluated by the FDA. The pneumococcal conjugate vaccine should be considered experimental, and has not been shown to be safe or efficacious for Streptococcus pneumoniae disease other than that caused by the serotypes included in the vaccine and for invasive infection, such as bacteremia or meningitis, caused by other microorganisms.


Assuntos
Infecções Pneumocócicas/prevenção & controle , Vacinas Pneumocócicas/administração & dosagem , Centers for Disease Control and Prevention, U.S. , Medicina Baseada em Evidências , Humanos , Lactente , National Institutes of Health (U.S.) , Otite Média/prevenção & controle , Vacinas Pneumocócicas/economia , Ensaios Clínicos Controlados Aleatórios como Assunto , Estados Unidos , United States Food and Drug Administration , Vacinas Conjugadas/administração & dosagem , Vacinas Conjugadas/economia
18.
Manag Care ; 9(3): 56-60, 63, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11066214

RESUMO

BACKGROUND INFORMATION: Percutaneous vertebroplasty is a therapeutic, interventional radiologic procedure that involves injection of bone cement into a cervical, thoracic, or lumbar vertebral body lesion for the relief of pain and the strengthening of bone. This procedure only recently has been introduced, and is being used for patients with lytic lesions due to bone metastases, aggressive hemangiomas, or multiple myeloma, and for patients who have medically intractable debilitating pain resulting from osteoporotic vertebral collapse. FINDINGS: Results from two uncontrolled prospective studies and several case series reports, including one with 187 patients, indicate that percutaneous vertebroplasty can produce significant pain relief and increase mobility in 70 percent to 80 percent of patients with osteolytic lesions in the vertebrae from hemangiomas, metastases, or myeloma, or with osteoporotic compression fractures. In these reports, pain relief was apparent within one to two days after injection, and persisted for at least several months up to several years. While experimental studies and preliminary clinical results suggest that percutaneous vertebroplasty can also strengthen the vertebral bodies and increase mobility, it remains to be proven whether this procedure can prevent additional fractures in the injected vertebrae. In addition, the duration of effect is not known; there were no long-term follow-up data on most of these patients, and these data may be difficult to obtain and interpret in patients with an underlying malignant process, because disease progression may confound evaluation of the treatment effect. Complications were relatively rare, although some studies reported a high incidence of clinically insignificant leakage of bone cement into the paravertebral tissues. In a few cases, the leakage of polymer caused compression of spinal nerve roots or neuralgia. Several instances of pulmonary embolism were also reported. Although patient selection criteria have not been definitely established, percutaneous vertebroplasty is considered appropriate treatment for patients with vertebral lesions resulting from osteolytic metastasis and myeloma, hemangioma, and painful osteoporotic compression fractures if the following criteria have been met: o Severe debilitating pain or loss of mobility that cannot be relieved by correct medical therapy. o Other causes of pain, such as herniated intervertebral disk have been ruled out by computed tomography or magnetic resonance imaging. o The affected vertebra has not been extensively destroyed and is at least one third of its original height. o Radiation therapy or concurrent surgical interventions, such as laminectomy, may also be required in patients with compression of the spinal cord due to ingrowth of a tumor. CONCLUSIONS: Percutaneous vertebroplasty has only recently been introduced as a treatment for osteolytic lesions and osteoporotic compression fractures of the vertebrae, but early results are promising. Up to 80 percent of patients with pain unresponsive to correct medical treatment experience a significant degree of pain relief, and few serious complications have been reported. However, relatively few patients have undergone this procedure, and there are no data from controlled clinical trials or from studies with long-term follow-up. At the present time this procedure is still in the investigational stages, but may be appropriate for patients with no other reasonable options for medical treatment.


Assuntos
Cimentos Ósseos/uso terapêutico , Medicina Baseada em Evidências , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Doenças da Coluna Vertebral/cirurgia , Coluna Vertebral/cirurgia , Cimentos Ósseos/efeitos adversos , Centers for Medicare and Medicaid Services, U.S. , Análise Custo-Benefício , Humanos , Procedimentos Cirúrgicos Minimamente Invasivos/efeitos adversos , Dor/etiologia , Dor/cirurgia , Radiologia Intervencionista , Doenças da Coluna Vertebral/complicações , Estados Unidos
19.
Kardiologiia ; 20(11): 39-43, 1980 Nov.
Artigo em Russo | MEDLINE | ID: mdl-7003192

RESUMO

With the use of computers it proved possible to distinguish the most informative electro- and phonocardiographic signs in variants of tonsillogenic affection of the heart and primary rheumatic carditis as the result of which the severity of the myocardial affection could be judged. These signs are very important in the choice of the treatment and in prognosis. Cardiac-type neurocirculatory dystonias are characterized by the fewest informative signs indicative of vegetative effects produced on the heart. In tonsillogenic myocardial dystrophy, the number of informative signs and their pronounced character increase, which is evidence of more complex disorders in the heart. The signs in infectious-allergic myocarditis and primary rheumatic carditis are common in character, which makes differential diagnosis difficult and calls for further research into new diagnostic methods. According to the phonocardiogram, a systolic murmur was present in patients of all the groups that were examined, which had specific features in neurocirculatory dystonia and in tonsillogenic myocardial dystrophy. No essential differences were found in myocarditides.


Assuntos
Cardiomiopatias/diagnóstico , Eletrocardiografia , Miocardite/diagnóstico , Fonocardiografia , Cardiopatia Reumática/diagnóstico , Tonsilite/complicações , Adolescente , Adulto , Cardiomiopatias/etiologia , Diagnóstico por Computador , Humanos , Astenia Neurocirculatória/diagnóstico
20.
Artigo em Russo | MEDLINE | ID: mdl-3364095

RESUMO

On the basis of the data from the registry of cerebral stroke (CS) cases in Novosibirsk (covering 937 patients and 314 healthy control subjects) the authors have made a mathematical analysis of 19 factors of the risk of disease development. Nine factors have been isolated whose varying combinations were most contributory to the risk of the development of CS in the studied population: cardiac diseases, transient disorder of the cerebral circulation, arterial hypertension, atherosclerosis, aggravated heredity for cardiovascular diseases, intermittent claudication, diabetes mellitus, systematic alcohol abuse, and hypodynamia. The authors have developed a practicable and reliable system for predicting the development of cerebral stroke in apparently healthy subjects (the accuracy of prediction is 86%).


Assuntos
Transtornos Cerebrovasculares/epidemiologia , População Urbana , Transtornos Cerebrovasculares/etiologia , Transtornos Cerebrovasculares/prevenção & controle , Humanos , Matemática , Prognóstico , Fatores de Risco , Sibéria
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA