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1.
J Med Primatol ; 52(2): 108-120, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36744630

RESUMO

BACKGROUND: Compatible pair housing of macaques in research settings increases species-typical behaviors and facilitates beneficial social buffering. It is not yet established whether these benefits are maintained after intrafacility transfer and domestic quarantine, which are two stressors that can lead to behavioral and clinical abnormalities. METHODS: We evaluated 40 adolescent male rhesus macaques who were single- or pair-housed immediately following an intrafacility transfer. We measured behavior, fecal cortisol, body weight, and diarrhea occurrence. Body weight and diarrhea occurrence were also retrospectively analyzed in an additional 120 adolescent rhesus who underwent a similar transfer. RESULTS AND CONCLUSIONS: Pair-housed macaques exhibited less of some undesirable behaviors (e.g., self-clasping) and experienced less diarrhea than single-housed subjects; however, no significant differences in cortisol levels or alopecia measures were found. The demonstrated beneficial effects of pair housing for rhesus macaques following intrafacility transfer and adjustment suggest pairing upon arrival at a new facility will bolster animal welfare.


Assuntos
Hidrocortisona , Quarentena , Animais , Masculino , Macaca mulatta , Quarentena/veterinária , Estudos Retrospectivos , Abrigo para Animais , Comportamento Social , Comportamento Animal
2.
Curr Biol ; 32(24): 5295-5308.e5, 2022 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-36473466

RESUMO

Understanding the molecular basis of reproductive isolation and speciation is a key goal of evolutionary genetics. In the South American genus Petunia, the R2R3-MYB transcription factor MYB-FL regulates the biosynthesis of UV-absorbing flavonol pigments, a major determinant of pollinator preference. MYB-FL is highly expressed in the hawkmoth-pollinated P. axillaris, but independent losses of its activity in sister taxa P. secreta and P. exserta led to UV-reflective flowers and associated pollinator shifts in each lineage (bees and hummingbirds, respectively). We created a myb-fl CRISPR mutant in P. axillaris and studied the effect of this single gene on innate pollinator preference. The mutation strongly reduced the expression of the two key flavonol-related biosynthetic genes but only affected the expression of few other genes. The mutant flowers were UV reflective as expected but additionally contained low levels of visible anthocyanin pigments. Hawkmoths strongly preferred the wild-type P. axillaris over the myb-fl mutant, whereas both social and solitary bee preference depended on the level of visible color of the mutants. MYB-FL, with its specific expression pattern, small number of target genes, and key position at the nexus of flavonol and anthocyanin biosynthetic pathways, provides a striking example of evolution by single mutations of large phenotypic effect.


Assuntos
Manduca , Fatores de Transcrição , Animais , Abelhas/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Antocianinas/metabolismo , Manduca/fisiologia , Flavonóis , Mutação , Flores/fisiologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Regulação da Expressão Gênica de Plantas
3.
Breast Cancer Res Treat ; 181(2): 361-367, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32277376

RESUMO

INTRODUCTION: Current guidelines for the treatment of phyllodes tumors recommend wide local excision for all histopathological subtypes. However, it is unknown which subtypes have tendency to recur after marginal or incomplete excision. This may lead to over-treatment by re-excision surgery for tumors with little or no potential to recur. MATERIALS AND METHODS: All patients with benign, borderline or malignant phyllode tumors presenting at our institution between 2000 and 2016 were retrospectively analyzed. RESULTS: A total of 57 patients could be included, of which 39 tumors were benign (60%), three were borderline (5%), and seven were malignant phyllodes tumors (12%). There were also eight phyllodes-like fibroadenomas (14%). Fifty-two patients (91%) underwent local excision as primary treatment, resulting in tumor-positive or close-resection margins in 32 patients (61.5%) of whom five patients (15.6%) had re-excision surgery. During a median follow-up of 5 years, local recurrence occurred in four patients (7.0%) with a median time-to-recurrence of 12 months. Borderline and malignant subtypes were associated with a significantly higher recurrence rate compared to other subtypes (p = 0.039). CONCLUSION: Although an adequate tumor-negative resection margin should be obtained for borderline and malignant phyllodes tumors, this study confirms that wide local excision is the appropriate primary treatment for all histopathological subtypes. However, if tumor-negative margins were not obtained at first excision, a wait-and-see approach is justified for benign phyllodes tumors.


Assuntos
Neoplasias da Mama/patologia , Recidiva Local de Neoplasia/patologia , Tumor Filoide/patologia , Adolescente , Adulto , Idoso , Neoplasias da Mama/cirurgia , Feminino , Seguimentos , Humanos , Margens de Excisão , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/cirurgia , Tumor Filoide/cirurgia , Prognóstico , Estudos Retrospectivos , Adulto Jovem
4.
Viruses ; 12(1)2020 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-31947801

RESUMO

We report on a novel RNA virus infecting the wasp Lysiphlebus fabarum, a parasitoid of aphids. This virus, tentatively named "Lysiphlebus fabarum virus" (LysV), was discovered in transcriptome sequences of wasps from an experimental evolution study in which the parasitoids were allowed to adapt to aphid hosts (Aphis fabae) with or without resistance-conferring endosymbionts. Based on phylogenetic analyses of the viral RNA-dependent RNA polymerase (RdRp), LysV belongs to the Iflaviridae family in the order of the Picornavirales, with the closest known relatives all being parasitoid wasp-infecting viruses. We developed an endpoint PCR and a more sensitive qPCR assay to screen for LysV in field samples and laboratory lines. These screens verified the occurrence of LysV in wild parasitoids and identified the likely wild-source population for lab infections in Western Switzerland. Three viral haplotypes could be distinguished in wild populations, of which two were found in the laboratory. Both vertical and horizontal transmission of LysV were demonstrated experimentally, and repeated sampling of laboratory populations suggests that the virus can form persistent infections without obvious symptoms in infected wasps.


Assuntos
Genoma Viral/genética , Vírus de Insetos/fisiologia , Vírus de RNA de Cadeia Positiva/fisiologia , Vespas/virologia , Sequência de Aminoácidos , Animais , Afídeos/parasitologia , Feminino , Variação Genética , Haplótipos , Vírus de Insetos/classificação , Vírus de Insetos/genética , Masculino , Filogenia , Vírus de RNA de Cadeia Positiva/classificação , Vírus de RNA de Cadeia Positiva/genética , Carga Viral , Proteínas Virais/genética , Vespas/fisiologia
5.
J Nurs Scholarsh ; 51(4): 470-479, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30920767

RESUMO

PURPOSE: The purpose of this study was to test how basic psychological needs satisfaction contributes to career commitment through career satisfaction among nurses. BACKGROUND: There is an increasing rate of turnover among nurses and a general shortage of nurses in many countries. This has made it necessary for researchers to focus on the career satisfaction of nurses and their commitment to their careers. DESIGN AND METHODS: A cross-sectional design was employed in a survey of 233 nurses in public hospitals in southeastern Nigeria. Participants responded to self-report measures of career commitment, career satisfaction, and work-related basic needs satisfaction. FINDINGS: In the regression-based path analysis, basic psychological needs satisfaction was positively related to career satisfaction (p < .001) and career commitment (p < .001) of nurses. Career satisfaction was positively related to career commitment (p < .05). Career satisfaction mediated the relationship between basic psychological needs satisfaction and career commitment (95% confidence interval [.009, .068]). CONCLUSIONS: The results show that basic psychological needs are relevant for employee commitment, giving support to the self-determination theory. Career satisfaction provides further explanations for the relationship between psychological needs satisfaction and career commitment, although there could be reverse causal links. CLINICAL RELEVANCE: The results advance knowledge on how satisfaction of basic psychological needs can increase career satisfaction and foster more career commitment. Designing work environments that help employees to fulfil their basic psychological needs is important in the retention of nurses.


Assuntos
Satisfação no Emprego , Recursos Humanos de Enfermagem Hospitalar/psicologia , Satisfação Pessoal , Adolescente , Adulto , Estudos Transversais , Feminino , Hospitais Públicos/estatística & dados numéricos , Humanos , Masculino , Pessoa de Meia-Idade , Nigéria , Autonomia Pessoal , Reorganização de Recursos Humanos , Análise de Regressão , Inquéritos e Questionários , Local de Trabalho/psicologia , Adulto Jovem
6.
Med J Aust ; 202(5): 247-50, 2015 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-25758694

RESUMO

OBJECTIVE: To determine the effectiveness of a care bundle, with a novel line maintenance procedure, in reducing the rate of central line-associated bloodstream infection (CLABSI) in the intensive care unit (ICU). DESIGN, PARTICIPANTS AND SETTING: Before-and-after study using CLABSI data reported to the Victorian Healthcare Associated Infection Surveillance System (VICNISS), in adult patients admitted to a tertiary adult ICU in regional Victoria between 1 July 2006 and 30 June 2014. VICNISS-reported CLABSI cases were reviewed for verification. An intervention was implemented in 2009. INTERVENTION: The care bundle introduced in 2009 included a previously established line insertion procedure and a novel line maintenance procedure comprising Biopatch, daily 2% chlorhexidine body wash, daily ICU central line review, and liaison nurse follow-up of central lines. MAIN OUTCOME MEASURES: CLABSI rate (cases per 1000 central line days). RESULTS: The average CLABSI rate fell from 2.2/1000 central line days (peak of 5.2/1000 central line days in quarter 4, 2008) during the pre-intervention period to 0.5/1000 central line days (0/1000 central line days from July 2012 to July 2014) during the post-intervention period. CONCLUSION: Our study suggests that this care bundle, using a novel maintenance procedure, can effectively reduce the CLABSI rate and maintain it at zero out to 2 years.


Assuntos
Bacteriemia/prevenção & controle , Infecções Relacionadas a Cateter/prevenção & controle , Cateterismo Venoso Central/efeitos adversos , Cuidados Críticos , Pacotes de Assistência ao Paciente , Adulto , Idoso , Austrália , Bacteriemia/epidemiologia , Bacteriemia/microbiologia , Infecções Relacionadas a Cateter/epidemiologia , Infecções Relacionadas a Cateter/microbiologia , Protocolos Clínicos , Estudos Controlados Antes e Depois , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
7.
J Proteome Res ; 12(3): 1254-65, 2013 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-23343621

RESUMO

Cerebrospinal fluid (CSF) rhinorrhea is a potentially dangerous condition identified by CSF leakage into the nasal cavity. This malady stands to benefit from rapid and noninvasive screening diagnostics to complement low-throughput imaging based methods currently in use. To address this gap, we demonstrate on-chip immunosubtraction to accelerate biomarker validation and immunoassay development for a putative CSF rhinorrhea diagnostic marker, transthyretin, by combining high-specificity immunoaffinity capture with subsequent polyacrylamide gel electrophoresis (PAGE). We demonstrate the on-chip assay using photopatterned polyacrylamide immunofilters. The filter consists of polymer with controlled pore-sizes to size-exclude (i.e., "subtract") large antibody-target immune complexes from downstream PAGE separation. A control PAGE separation is also performed for comparison without immunoaffinity capture (i.e., no antibody present). We compare on-chip immunosubtraction to Western blotting and ELISA to validate CSF rhinorrhea biomarkers from nasal surgery samples. For samples representative of spontaneous rhinorrhea, the 5 min on-chip assay achieved clinical specificity of 100%, compared to 50% for ELISA which required 6 h. On-chip immunosubtraction also generated results for clinical samples not assayable via ELISA due to matrix protein spurious signals. The pilot study suggests the capability of a rapid on-chip validation tool to expedite scrutiny of putative protein markers for new clinical assays.


Assuntos
Biomarcadores/líquido cefalorraquidiano , Rinorreia de Líquido Cefalorraquidiano/diagnóstico , Microfluídica , Western Blotting , Rinorreia de Líquido Cefalorraquidiano/líquido cefalorraquidiano , Eletroforese em Gel de Poliacrilamida , Ensaio de Imunoadsorção Enzimática , Humanos , Espectrometria de Massas
8.
Zh Evol Biokhim Fiziol ; 44(1): 72-7, 2008.
Artigo em Russo | MEDLINE | ID: mdl-18411516

RESUMO

The study has been carried out to verify the authors' hypothesis that degeneration of dopaminergic (DA-ergic) neurons of the hypothalamic tuberoinfundibular system and concomitant development of hyperprolactinemia are accompanied by involvement of compensatory synthesis of dopamine (DA) by non-dopaminergic neurons expressing single complementary enzymes of synthesis of this neurotransmitter. Degeneration of DA-ergic neurons was produced by a stereotaxic injection into the brain lateral ventricles of 6-hydroxydopamine (6-OHDA) - a specific neurotoxin of DA-ergic neurons. 14 and 45 days after the toxin administration there were determined concentration of prolactine in peripheral blood by methods of immunoenzyme and radioimmunological analyses as well as the DA amount in the arcuate nucleus by the method of highly efficient liquid chromatography with electrochemical detection. In a part of the animals, slices were prepared from the mediobasal hypothalamus (arcuate nucleus and medial eminence) and perfused with Krebs-Ringer medium; then the DA concentration was determined in the slices and in the incubation medium. 14 days after the neurotoxin administration there were revealed an increase of blood prolactine concentration and a decrease of DA concentration in the arcuate nucleus in vivo as well a decrease of the total DA amount in the slices and incubation medium in experiments in vitro. 45 days after the neurotoxin administration, all the above parameters returned to the normal level. This, the obtained data indicate that the hyperlactinemia and DA deficit appearing during degeneration of the arcuate nucleus DA-ergic neurons seem to be compensated due to an enhancement of DA synthesis by non-dopaminergic monoenzyme neurons of arctuate nucleus.


Assuntos
Núcleo Arqueado do Hipotálamo/metabolismo , Dopamina/metabolismo , Degeneração Neural/metabolismo , Neurônios/metabolismo , Prolactina/metabolismo , Adrenérgicos/toxicidade , Animais , Núcleo Arqueado do Hipotálamo/patologia , Masculino , Degeneração Neural/induzido quimicamente , Degeneração Neural/patologia , Neurônios/patologia , Neurotoxinas/toxicidade , Oxidopamina/toxicidade , Ratos , Ratos Wistar
9.
Curr Opin Struct Biol ; 17(4): 454-9, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17884462

RESUMO

In nature similar protein folds accommodate distant sequences and support diverse functions. This observation coupled with the recognition that proteins can tolerate many homologous substitutions inspires protein engineers to use recombination to search for new functions within sequences encoding structurally related molecules. These searches have led to proteins with novel activities, diversified specificities and greater stabilities. Computational methods that exploit structural and evolutionary information are being used to design highly mutated yet still natively folded chimeric proteins and protein libraries.


Assuntos
Engenharia de Proteínas , Dobramento de Proteína , Proteínas Recombinantes de Fusão/química , Motivos de Aminoácidos , Animais , Sequência Conservada , Evolução Molecular , Humanos , Estrutura Terciária de Proteína , Proteínas Recombinantes de Fusão/metabolismo , Recombinação Genética , Relação Estrutura-Atividade
10.
Biotechnol Bioeng ; 93(6): 1221-4, 2006 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-16440348

RESUMO

The kinetics of lysozyme crystallization under seeded isothermal batch conditions was followed by measurement of the decline in solution concentration versus time. Kinetics were measured for five different values of the seed crystal mass. The data were analyzed using a recently proposed mathematical model. For each seed mass, the model fit the kinetic data well. Growth rate constants determined using the model were approximately constant over a sixfold increase in the seed crystal mass, and fell well within the range of values reported in the literature, but obtained using entirely different experimental techniques. These results confirmed the utility of the proposed model. The proposed model can be used to analyze crystallization kinetics using absorbance measurements only, without the need to characterize the crystal size, thus avoiding the need for expensive laser light scattering and digital microscopy instrumentation. Thus, the model offers a low-cost straightforward method to analyze and simulate the effects of changes in operating parameters such as the seed crystal mass, solution volume, initial protein concentration, pH, temperature, salt concentration, and time.


Assuntos
Cristalização/métodos , Modelos Teóricos , Muramidase/química , Algoritmos , Animais , Galinhas , Concentração de Íons de Hidrogênio , Cinética , Temperatura , Fatores de Tempo
11.
Biotechnol Bioeng ; 91(1): 84-90, 2005 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-15889398

RESUMO

Bulk protein crystallization, unlike small molecule crystallization, has found very limited use in biopharmaceutical manufacture. Most work in this area targets obtaining single large crystals for molecular structure determination by crystallography. Design and optimization of bulk crystallization for protein recovery and purification is much less common, and requires a mathematical model for analysis of laboratory data suitable for scale-up purposes. Traditionally, the crystal size distribution and method of moments is used to characterize the crystallization process. A simpler method is presented in this paper that utilizes the desupersaturation curve. The method uses an approach that does not require expensive instrumentation or characterization of the seed crystal size distribution. The method is extended to allow determination of both the mass deposition rate constant and the growth rate order from a single desuperaturation curve. Experimental data for the bulk crystallization of ovalbumin are used to validate the method. The rate constants and rate order obtained using the new method compare well with literature values. Scale-up is illustrated by prediction of the impact of changes in seed mass on protein crystallization. This new method offers a straightforward and low-cost alternative to traditional methods for the analysis and scale-up of protein crystallization data.


Assuntos
Cristalização/métodos , Modelos Químicos , Proteínas/análise , Proteínas/química , Simulação por Computador , Cinética , Temperatura
12.
J Oncol Manag ; 14(4): 20-8, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16454115

RESUMO

A key challenge in cancer control is the need for translational research to link discovery research with improved health outcomes. In British Columbia, we have built upon the idea of communities of practice to develop networks that will meet our cancer-control mandate.


Assuntos
Prestação Integrada de Cuidados de Saúde/organização & administração , Oncologia , Neoplasias/prevenção & controle , Colúmbia Britânica , Humanos , Programas Nacionais de Saúde , Neoplasias/mortalidade , Objetivos Organizacionais
13.
J Nutr ; 132(6): 1384-90, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12042463

RESUMO

Recent advances in agricultural biotechnology have highlighted the need for experimental evidence and sound scientific judgment to assess the benefits and risks to society. Nutrition scientists and other animal biologists need a balanced understanding of the issues to participate in this assessment. To date most modifications to crop plants have benefited producers. Crops have been engineered to decrease pesticide and herbicide usage, protect against stressors, enhance yields and extend shelf life. Beyond the environmental benefits of decreased pesticide and herbicide application, consumers stand to benefit by development of food crops with increased nutritional value, medicinal properties, enhanced taste and esthetic appeal. There remains concern that these benefits come with a cost to the environment or increased risk to the consumer. Most U.S. consumers are not aware of the extent that genetically modified foods have entered the marketplace. Consumer awareness of biotechnology seems to have increased over the last decade, yet most consumers remain confused over the science. Concern over the impact on the safety of the food supply remains low in the United States, but is substantially elevated in Europe. Before a genetically engineered crop is introduced into commerce it must pass regulatory scrutiny by as many as four different federal regulatory bodies to ensure a safe food supply and minimize the risk to the environment. Key areas for more research are evaluation of the nutritional benefits of new crops, further investigation of the environmental impact, and development of better techniques to identify and track genetically engineered products.


Assuntos
Agricultura/métodos , Biotecnologia/normas , Tecnologia de Alimentos/normas , Engenharia Genética/normas , Plantas Geneticamente Modificadas , Conscientização , Biotecnologia/tendências , Qualidade de Produtos para o Consumidor , Alimentos , Tecnologia de Alimentos/tendências , Engenharia Genética/tendências , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Estados Unidos
14.
Hum Reprod ; 14 Suppl 2: 90-6, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10690804

RESUMO

Insulin-like growth factor-II (IGF-II) and IGF binding protein-1 (IGFBP-1) appear to play an important role in paracrine interactions at the maternal-fetal interface in human pregnancy. Patterns of expression of IGF-II and IGFBP-1 at the decidual-trophoblast interface suggest paracrine interactions occur between the IGF-II-expressing invading cytotrophoblast and maternal decidua-derived IGFBP-1. Autocrine/paracrine actions of trophoblast-derived IGF-II may be important in invasion, and for both trophoblast and decidual function. The actions of IGFBP-1 in binding IGF, and as an integrin ligand, suggest it may have multiple roles in the interactions between the invading trophoblast and the maternal decidua. Abundant decidual IGFBP-1 may interact with the IGF-II-expressing, protease-secreting trophoblast to modulate invasion. In-vitro studies of trophoblast-decidual cell interactions in invasion, and clinical observations in a gestational disorder with shallow placental invasion such as pre-eclampsia, have provided new insights into the possible role(s) of IGFBP-1 in trophoblast invasion. The precise mechanisms underlying IGF and IGFBP-1 action at the decidual-trophoblast interface remain to be elucidated. The potential predictive value of serum IGFBP-1 concentrations in pre-eclampsia also remains to be established.


Assuntos
Implantação do Embrião/fisiologia , Pré-Eclâmpsia/fisiopatologia , Somatomedinas/fisiologia , Trofoblastos/fisiologia , Decídua/fisiologia , Feminino , Humanos , Proteína 1 de Ligação a Fator de Crescimento Semelhante à Insulina/fisiologia , Gravidez
15.
J Clin Endocrinol Metab ; 82(6): 1894-8, 1997 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9177402

RESUMO

The insulin-like growth factors (IGFs) and their binding proteins (IGFBPs) are important regulators of fetal and maternal tissue development during pregnancy. Posttranslational modification of IGFBP-1 yields up to six IGFBP-1 phosphovariants and a nonphosphorylated form, which in vitro, have some different properties. Nonphospho IGFBP-1 has less affinity for IGFs than the phospho isoforms and also may have IGF-independent actions. Herein, we have investigated the complement of IGFBP-1 phosphoisoforms present in extraembryonic coelomic (EEC) fluid, amniotic fluid (AF), and maternal serum (MS) throughout human gestation. Also, to determine potential tissue source(s) of IGFBP-1 in these fluids, we have quantified IGFBP-1 and examined IGFBP-1 phosphoisoforms in conditioned media (CM) from maternal decidua, fetal liver, and fetal kidney explants throughout gestation. Western immunodetection revealed that IGFBP-1, present in EEC and AF in early pregnancy and in CM from early pregnancy decidua, is primarily in the nonphosphorylated form. MS in this period contains primarily the nonphospho form and, as in nonpregnant adults, the highly phosphorylated form of IGFBP-1. The phosphorylation profile of IGFBP-1 in AF, MS, and decidua CM changes as pregnancy progresses. All the IGFBP-1 phosphoisoforms ultimately are produced by decidua and are present in midgestation MS, and all but the most highly phosphorylated form are present in AF. In late gestation, MS contains primarily the highly phosphorylated form. In contrast, profiles in CM from explants of fetal liver and kidney at different gestational ages remain unchanged. Nonphosphorylated IGFBP-1 is the primary form in fetal kidney CM, whereas fetal liver CM contains all IGFBP-1 phosphoisoforms. Concentrations of IGFBP-1 in fetal liver and kidney CM are significantly lower (482 +/- 146 and 120 +/- 32 ng/mL x 100 mg wet wt tissue, respectively) than in decidua CM (11,417 +/- 2,358 ng/mL x 100 mg wet wt tissue). The data cumulatively suggest that maternal decidua is the primary source of IGFBP-1 in EEC, AF, and MS in early pregnancy and that fetal liver and kidney are not likely significant contributors. The presence of nonphospho IGFBP-1 in AF, EEC, and MS suggests an important role for this isoform during early gestation.


Assuntos
Líquidos Corporais/metabolismo , Decídua/metabolismo , Proteína 1 de Ligação a Fator de Crescimento Semelhante à Insulina/metabolismo , Gravidez/metabolismo , Meios de Cultivo Condicionados/metabolismo , Técnicas de Cultura , Feminino , Feto/metabolismo , Humanos , Proteína 1 de Ligação a Fator de Crescimento Semelhante à Insulina/sangue , Isomerismo , Rim/embriologia , Fígado/embriologia , Fosforilação , Gravidez/sangue , Primeiro Trimestre da Gravidez
16.
Am J Obstet Gynecol ; 176(4): 751-7; discussion 757-8, 1997 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9125598

RESUMO

OBJECTIVES: Preeclampsia is characterized by maternal hypertension, proteinuria, edema, and shallow placental invasion. Insulin-like growth factor binding protein-1, abundant in maternal decidua, is believed to play a role in limiting trophoblast invasiveness. In this study we addressed the hypothesis that this binding protein is aberrantly expressed in preeclampsia. We also investigated circulating levels of insulin-like growth factor-I and insulin-like growth factor-II in subjects with severe preeclampsia compared with controls. STUDY DESIGN: Insulin-like growth factor binding protein-1 was investigated by immunohistochemistry at the maternal-fetal interface of eight pregnancies complicated by severe preeclampsia and six controls between 21 and 34 weeks of gestation. Cell types were identified with use of cell-specific markers. Circulating levels of insulin-like growth factor binding protein-1, insulin-like growth factor-I, and insulin-like growth factor-II in 16 patients with severe preeclampsia and 29 controls at the same gestational age were determined by an immunoradiometric assay and correlated with clinical parameters. Data were analyzed by t test and Pearson's method. RESULTS: Insulin-like growth factor binding protein-1 was highly expressed on syncytiotrophoblasts, cytotrophoblasts, and decidual cells but not on placental fibroblasts. Immunostaining was greater at the maternal-fetal interface in severe preeclamptic patients compared with controls. Circulating insulin-like growth factor binding protein-1 levels in subjects with severe preeclampsia were 428.3 +/- 85.9 ng/ml compared with 76.6 +/- 11.8 in controls (p = 0.0007). Circulating insulin-like growth factor-I levels were 80.9 +/- 17.2 ng/ml compared with 179.4 +/- 28.2 ng/ml in controls (p = 0.0001). In contrast, insulin-like growth factor-II levels were not significantly different in the two groups. In subjects with severe preeclampsia insulin-like growth factor binding protein-1 levels correlated with diastolic blood pressure (r = 0.498, p 0.049) and aspartate transcarbamylase (0.621, p = 0.010). CONCLUSIONS: The abundance of insulin-like growth factor binding protein-1 at the maternal-fetal interface in severely preeclamptic pregnancies suggests that the binding protein may participate in the pathogenesis of the shallow placental invasion observed in this disorder. Low circulating insulin-like growth factor-I and elevated insulin-like growth factor binding protein-1 levels may contribute to restricted placental and therefore fetal growth.


Assuntos
Decídua/química , Proteína 1 de Ligação a Fator de Crescimento Semelhante à Insulina/análise , Fator de Crescimento Insulin-Like II/análise , Fator de Crescimento Insulin-Like I/análise , Pré-Eclâmpsia/patologia , Trofoblastos/química , Adolescente , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Proteína 1 de Ligação a Fator de Crescimento Semelhante à Insulina/sangue , Trabalho de Parto Prematuro/sangue , Trabalho de Parto Prematuro/patologia , Pré-Eclâmpsia/sangue , Gravidez/sangue , Segundo Trimestre da Gravidez , Terceiro Trimestre da Gravidez
17.
Gene ; 176(1-2): 211-4, 1996 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-8918255

RESUMO

With use of the signal sequence trap method, we isolated a cDNA encoding a novel secretory protein, SDF-2, from the mouse stromal cell line, ST2. The human homologue of SDF-2 was also isolated. The amino acid (aa) sequences deduced from both the clones were conserved more than 92%. The chromosomal localization of the human SDF-2 gene was mapped to 17q11.2. The aa sequence of SDF-2 shows similarity to those of yeast dolichyl phosphate-D-mannose:protein mannosyltransferases, Pmt1p [Strahl-Bolsinger et al. (1993) Proc. Natl. Acad. Sci. USA 90, 8164-8168] and Pmt2p [Lussier et al. (1995) J. Biol. Chem. 270, 2770-2775], whose activities have not been detected in higher eukaryotes.


Assuntos
Cromossomos Humanos Par 17 , Sequência Conservada , Proteínas/genética , Células Estromais/metabolismo , Sequência de Aminoácidos , Animais , Sequência de Bases , Linhagem Celular , Mapeamento Cromossômico , DNA Complementar , Evolução Molecular , Expressão Gênica , Humanos , Manosiltransferases/genética , Camundongos , Dados de Sequência Molecular , RNA Mensageiro , Homologia de Sequência do Ácido Nucleico , Células Estromais/citologia
18.
Leukemia ; 8(8): 1359-68, 1994 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8057674

RESUMO

Uncontrolled proliferation of acute myeloid leukemia (AML) cells is an important step during leukemogenesis. However, little is known about the mechanisms leading to growth autonomy. Studies using immortalized murine hematopoietic cell lines have suggested that autocrine production of growth factors, or the constitutive activation of molecules in growth factor signalling pathways, are involved. We have established six spontaneous factor-independent cell lines from the human growth factor-dependent TF-1 cell line. The factor-independent cells showed no detectable growth factor activity. Immunoblotting analyses of tyrosine phosphorylation, Raf-1 and extracellular signal-regulated kinase 2 (ERK-2) showed a similar pattern in all the cell lines including TF-1 cells. Furthermore, somatic-cell hybrids between TF-1 and the factor-independent cells grew in absence of growth factor. Taken together this data demonstrates that the factor independence in this system is dominant and suggests that the molecular event is located either downstream of the Raf-1 and MAP kinases pathway or on an alternative pathway. Finally, the karyotype analysis of one factor-independent cell line TF-1i1 and TF-1H- (G418 resistant, HAT sensitive TF-1 cells) and their hybrids demonstrated an unstable derivative chromosome [der(19) t(19;?) (q13.1;?)] which seemed to correlate with the factor-independence capacity. This model may help in our understanding of autonomous proliferation by human myeloid leukemias.


Assuntos
Proteínas Quinases Dependentes de Cálcio-Calmodulina/biossíntese , Fator Estimulador de Colônias de Granulócitos e Macrófagos/biossíntese , Fator Estimulador de Colônias de Granulócitos e Macrófagos/farmacologia , Proteínas Serina-Treonina Quinases/biossíntese , Proteínas Tirosina Quinases/biossíntese , Proteínas Proto-Oncogênicas/biossíntese , Doença Aguda , Animais , Sequência de Bases , Proteínas Quinases Dependentes de Cálcio-Calmodulina/isolamento & purificação , Divisão Celular/efeitos dos fármacos , Linhagem Celular , Primers do DNA , Fator Estimulador de Colônias de Granulócitos e Macrófagos/genética , Humanos , Leucemia Mieloide , Camundongos , Proteína Quinase 1 Ativada por Mitógeno , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Proteínas Serina-Treonina Quinases/isolamento & purificação , Proteínas Tirosina Quinases/isolamento & purificação , Proteínas Proto-Oncogênicas/isolamento & purificação , Proteínas Proto-Oncogênicas c-raf , Células Tumorais Cultivadas
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