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31.
Atemezem A Mbemba E Marfaing R Vaysse J Pontet M Saffar L Charnaux N Gattegno L 《Biochemical and biophysical research communications》2002,296(3):507-514
We have previously reported that alpha-fetoprotein (AFP) inhibits infection of human monocyte-derived macrophages (MDM) by R5-HIV-1 strains and that a peptide mimicking the clade B HIV-1 gp120 consensus V3 domain (V3Cs) binds to CCR5. We demonstrate here that AFP binds high- and low-affinity binding sites of MDM, characterized, respectively, by 5.15 and 100nM K(d) values. Heat denaturation or neuraminidase treatment of AFP inhibits this binding, suggesting the involvement of protein-protein and lectin-carbohydrate interactions. Moreover, AFP displaces V3Cs binding to MDM. In addition, MIP-1beta, the most specific CCR5 ligand, displaces AFP binding to MDM (IC(50)=4.3nM). Finally, we demonstrate that AFP binds to a ligand of HIV-gp120 V3Cs domain, CCR5, expressed by MDM and by HeLa cells expressing CCR5. Such binding is not observed in the presence of HeLa cells lacking CCR5. The present results provide strong evidence that AFP directly binds to CCR5 expressed by human primary macrophages and by transfected CCR5+ HeLa cells. 相似文献
32.
Eigenheer RA Wiehart UM Nicolson SW Schoofs L Schegg KM Hull JJ Schooley DA 《Peptides》2003,24(1):27-34
We isolated from head extracts of Tenebrio molitor a peptide that inhibits fluid secretion by the Malpighian tubules of this insect. This second antidiuretic factor, ADFb, like the previously published ADFa, works through cyclic GMP as a second messenger. It has primary structure Tyr-Asp-Asp-Gly-Ser-Tyr-Lys-Pro-His-Ile-Tyr-Gly-Phe-OH with an EC(50) of approximately 240 pM in a fluid secretion assay. This peptide is now the second sequenced endogenous insect ADF which inhibits Malpighian tubule fluid secretion. Immunohistochemical techniques show that the peptide is localized in the brain; it appears to be produced mainly in two pairs of bilaterally symmetrical cells in the protocerebrum. 相似文献
33.
Cointeaux L Berrien JF Peyrou V Provot O Ciceron L Danis M Robert A Meunier B Mayrargue J 《Bioorganic & medicinal chemistry letters》2003,13(1):75-77
2-Methoxyprop-2-yl peroxides were synthesized and evaluated in vitro against Plasmodium falciparum. These acyclic artemisinin-related peroxides revealed moderate to good activity but were devoid of alkylating property towards the synthetic model of heme Mn(II)-TPP. 相似文献
34.
Kurt Boonen John W. Creemers Liliane Schoofs 《BioEssays : news and reviews in molecular, cellular and developmental biology》2009,31(3):300-314
Bioactive peptides are a group of diverse intercellular signalling molecules. Almost half a century of research on this topic has resulted in an enormous amount of data. In this essay, a general perspective to interpret all these data will be given. In classical endocrinology, neuropeptides were thought of as simple signalling molecules that each elicit one response. However, the fact that the total bioactive peptide signal is far from simple puts this view under pressure. Cells and tissues express many different bioactive peptides and they are also able to respond to many different bioactive peptides, indicating that multiple receptors and signal transduction pathways are present in a single cell. Therefore, the authors suggest that the bioactive peptide signalling system should be regarded in the context of network and systems biology. Bioactive peptides can best be viewed as an extension of the protein interaction network that allows regulating and fine‐tuning the metabolism of the different cells and tissues in the body. The cell thus responds to the ‘peptidome’ instead of to a single peptide. The intracellular part of this signalling network consists of the various signalling transduction cascades. Recently, new systems biology approaches have emerged for the modelling of cell signalling. The network and systems biology approach is also able to shed new light on the evolution of intercellular signalling. 相似文献
35.
Frederico Figueiredo Amancio Tiago Pires Heringer Cristina da Cunha Hueb Barata de Oliveira Liliane Boaventura Fassy Frederico Bruzzi de Carvalho Daniela Pagliari Oliveira Claudio Dornas de Oliveira Fernando Otoni Botoni Fernanda do Carmo Magalh?es José Roberto Lambertucci Mariangela Carneiro 《PloS one》2015,10(6)
The purpose of our study was to describe the clinical profile of dengue-infected patients admitted to Brazilian intensive care units (ICU) and evaluate factors associated with death. A longitudinal, multicenter case series study was conducted with laboratory-confirmed dengue patients admitted to nine Brazilian ICUs situated in Minas Gerais state, southeastern Brazil from January 1, 2008, to December 31, 2013. Demographic, clinical and laboratory data; disease severity scores; and mortality were evaluated. A total of 97 patients were studied. The in-ICU and in-hospital mortality rates were 18.6% and 19.6%, respectively. Patients classified as having severe dengue according to current World Health Organization classifications showed an increased risk of death in a univariate analysis. Nonsurvivors were older, exhibited lower serum albumin concentrations and higher total leukocyte counts and serum creatinine levels. Other risk factors (vomiting, lethargy/restlessness, dyspnea/respiratory distress) were also associated with death in a univariate analysis. Multivariate analysis indicated that in-hospital mortality was significantly associated with Acute Physiology and Chronic Health Evaluation II and the Sequential Organ Failure Assessment score. The ICU and in-hospital mortality observed in this study were higher than values reported in similar studies. An increased frequency of ICU admission due to severe organ dysfunction, higher severity indices and scarcity of ICU beds may partially explain the higher mortality. 相似文献
36.
Natacha Dreumont Sara Hardy Isabelle Behm-Ansmant Liliane Kister Christiane Branlant James Stévenin Cyril F. Bourgeois 《Nucleic acids research》2010,38(4):1353-1366
Alternative splicing is regulated in part by variations in the relative concentrations of a variety of factors, including serine/arginine-rich (SR) proteins. The SR protein SC35 self-regulates its expression by stimulating unproductive splicing events in the 3′ untranslated region of its own pre-mRNA. Using various minigene constructs containing the terminal retained intron and flanking exons, we identified in the highly conserved last exon a number of exonic splicing enhancer elements responding specifically to SC35, and showed an inverse correlation between affinity of SC35 and enhancer strength. The enhancer region, which is included in a long stem loop, also contains repressor elements, and is recognized by other RNA-binding proteins, notably hnRNP H protein and TAR DNA binding protein (TDP-43). Finally, in vitro and in cellulo experiments indicated that hnRNP H and TDP-43 antagonize the binding of SC35 to the terminal exon and specifically repress the use of SC35 terminal 3′ splice site. Our study provides new information about the molecular mechanisms of SC35-mediated splicing activation. It also highlights the existence of a complex network of self- and cross-regulatory mechanisms between splicing regulators, which controls their homeostasis and offers many ways of modulating their concentration in response to the cellular environment. 相似文献
37.
Ana Paula Chiaverini Pinto Alessandra Cristina B. A. Monteiro-Hara Liliane Cristina Liborio Stipp Beatriz Madalena Januzzi Mendes 《In vitro cellular & developmental biology. Plant》2010,46(1):28-33
Passiflora alata in vitro organogenesis was studied based on explant type, culture medium composition, and incubation conditions. The results indicated
that the morphogenic process occurred more efficiently when hypocotyl segment-derived explants were cultured in media supplemented
with cytokinin and AgNO3 incubated under a 16-h photoperiod. The shoot bud elongation and plant development were obtained by transferring the material
to MSM culture medium supplemented with GA3 and incubated in flasks with vented lids. Histological analyses of the process revealed that the difficulties in obtaining
plants could be related to the development of protuberances and leaf primordia structures, which did not contain shoot apical
meristem. Roots developed easily by transferring elongated shoots to 1/2 MSM culture medium. Plant acclimatization occurred
successfully, and somaclonal variation was not visually detected. The efficiency of this organogenesis protocol will be evaluated
for genetic transformation of this species to obtain transgenic plants expressing genes that can influence the resistance
to Cowpea aphid borne mosaic virus. 相似文献
38.
Marreiro DN do Perpetuo Socorro C Martins M de Sousa SS Ibiapina V Torres S Pires LV do Nascimento Nogueira N Lima JM do Monte SJ 《Biological trace element research》2007,120(1-3):42-50
The objective of this study was to assess urinary excretion of zinc and evaluation parameters of metabolic control in type
2 diabetic patients. Thirty-one type 2 diabetic patients, of both genders, with 5.8 ± 5.6 years average time of the disease,
age range 20–60 years, were selected. Evaluation of the nutritional status was performed using anthropometric measurements.
To evaluate food consumption, the 3-day alimentary log method was used, and its analysis was performed using a software. Determination
of urinary zinc was by atomic absorption spectrophotometry. From the obtained results, it was concluded that 51.6% of the
patients were overweight. The mean of found waist circumference was 100.4 and 92.2 cm for men and women, respectively. Blood
glucose and glycated hemoglobin values were higher than reference values, and plasma albumin concentration was adequate. The
median of found urinary zinc excretion was 474.9 μg/24 h, within normal standards (300–600 μg/day). Regarding diet composition,
calorie and protein concentration were above recommendation, while mean zinc concentration was adequate. This data allow the
conclusion that the evaluated patients presented adequate urinary zinc excretion in comparison with reference values. 相似文献
39.
40.
Virginie?Barraud-Lange Nathalie?Naud-Barriant Line?Saffar Liliane?Gattegno Beatrice?Ducot Anne-Sophie?Drillet Morgane?Bomsel Jean-Philippe?WolfEmail author Ahmed?Ziyyat 《BMC developmental biology》2007,7(1):102