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1.
J Biol Regul Homeost Agents ; 35(1 Suppl. 2): 15-19, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33982533

RESUMO

COVID-19, the disease caused by the SARS - CoV - 2 pathogen, is currently a pandemic. At the moment there is not an available vaccine, so, scientific community is looking for strategies and drugs to implement prevention and prophylaxis. Several compounds are examined for this purpose. Glycyrrhizin, an alkaloid extracted from licorice plant (glycyrriza glabra), is one of the most studied molecules, both for its peculiar biological functions and for its pharmacological effects. This brief review aims to highlight the characteristics of glycyrrhizin for topical use on the nasal and ocular surfaces. The anti-inflammatory activity, the ability to inhibit the accumulation of ROS, the antiviral property, but, above all, the ability to bind the ACE receptor and the SARS - CoV-2 protein S in the extracellular environment make Glycyrrhizzin for topical use a compound with a high prophylactic potential for SARS - CoV - 2 infection, also due to its low cost and the absence of significant side effects.


Assuntos
COVID-19 , Ácido Glicirrízico , Antivirais/uso terapêutico , Ácido Glicirrízico/farmacologia , Humanos , Pandemias , SARS-CoV-2
2.
Public Health ; 148: 109-116, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28475960

RESUMO

OBJECTIVE: This study assessed the effects of particulate matter (PM), equal or less than 10 µm in aerodynamic diameter (PM10), from the Middle-Eastern Dust events on public health in the megacity of Kermanshah (Iran). STUDY DESIGN: This study used epidemiological modeling and monitored ambient air quality data to estimate the potential PM10 impacts on public health. METHODS: The AirQ2.2.3 model was used to calculate mortality and morbidity attributed to PM10 as representative of dust events. Using Visual Basic for Applications, the programming language of Excel software, hourly PM10 concentrations obtained from the local agency were processed to prepare input files for the AirQ2.2.3 model. RESULTS: Using baseline incidence, defined by the World Health Organization, the number of estimated excess cases for respiratory mortality, hospital admissions for chronic obstructive pulmonary disease, for respiratory diseases, and for cardiovascular diseases were 37, 39, 476, and 184 persons, respectively, from 21st March, 2014 to 20th March, 2015. Furthermore, 92% of mortality and morbidity cases occurred in days with PM10 concentrations lower than 150 µg/m3. The highest percentage of person-days occurred for daily concentrations range of 100-109 µg/m3, causing the maximum health end-points among the citizens of Kermanshah. CONCLUSIONS: Calculating the number of cumulative excess cases for mortality or morbidity attributed to PM10 provides a good tool for decision and policy-makers in the field of health care to compensate their shortcomings particularly at hospital and healthcare centers for combating dust storms. To diminish these effects, several immediate actions should be managed in the governmental scale to control dust such as spreading mulch and planting new species that are compatible to arid area.


Assuntos
Poeira , Exposição Ambiental/efeitos adversos , Material Particulado/efeitos adversos , Saúde Pública/estatística & dados numéricos , Cidades , Humanos , Irã (Geográfico)/epidemiologia , Morbidade , Mortalidade , Medição de Risco
4.
Genomics ; 103(5-6): 337-48, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24667242

RESUMO

Within the complex pathological picture associated to diabetes, high glucose (HG) has "per se" effects on cells and tissues that involve epigenetic reprogramming of gene expression. In fetal tissues, epigenetic changes occur genome-wide and are believed to induce specific long term effects. Human umbilical vein endothelial cells (HUVEC) obtained at delivery from gestational diabetic women were used to study the transcriptomic effects of chronic hyperglycemia in fetal vascular cells using Affymetrix microarrays. In spite of the small number of samples analyzed (n=6), genes related to insulin sensing and extracellular matrix reorganization were found significantly affected by HG. Quantitative PCR analysis of gene promoters identified a significant differential DNA methylation in TGFB2. Use of Ea.hy926 endothelial cells confirms data on HUVEC. Our study corroborates recent evidences suggesting that epigenetic reprogramming of gene expression occurs with persistent HG and provides a background for future investigations addressing genomic consequences of chronic HG.


Assuntos
Diabetes Gestacional/genética , Epigênese Genética , Células Endoteliais da Veia Umbilical Humana/metabolismo , Transcriptoma , Adulto , Sequência de Bases , Estudos de Casos e Controles , Células Cultivadas , Metilação de DNA , Primers do DNA/genética , Diabetes Gestacional/metabolismo , Feminino , Perfilação da Expressão Gênica , Redes Reguladoras de Genes , Humanos , Anotação de Sequência Molecular , Análise de Sequência com Séries de Oligonucleotídeos , Gravidez , Regiões Promotoras Genéticas , Cordão Umbilical/patologia
5.
Nutr Metab Cardiovasc Dis ; 24(12): 1337-45, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25438716

RESUMO

BACKGROUND AND AIMS: Gestational diabetes (GDM) is associated with increased oxidative stress and overexpression of inflammatory cytokines, both of which might lead to endothelial dysfunction and vascular disease. As such, GDM could be viewed as a sort of 'short lived' metabolic syndrome. As umbilical cord vessels represent a suitable model for the study of vascular alterations brought about by GDM, the aim of the present work was to characterize the phenotype of human umbilical vein endothelial cells (HUVECs) chronically exposed to hyperglycaemia and to a pro-inflammatory environment during pregnancy so as to identify molecular modifications of cellular homoeostasis eventually impacting on endothelial dysfunction. METHODS AND RESULT: Tissue specimens and HUVECs were obtained from umbilical cords of GDMand control women. As compared to controls, GD-HUVEC exhibited enhanced monocyte adhesion and vascular cell adhesion molecule-1 (VCAM-1) and intercellular adhesion molecule-1(ICAM-1) expression and exposure on plasma membrane after tumour necrosis factor-alpha(TNF-α) stimulation (Western blot, flow cytometer). As compared to control cells, GD-HUVEC in basal conditions exhibited enhanced monocyte adhesion, nitric oxide synthase (NOS) expression and activity (eNOS Real-Time polymerase chain reaction, Western Blot for eNOS total protein and monomers/dimers ratio, conversion of [3H]-L-arginine in [3H]-L-citrulline), increased O(-)(2)egeneration together with increased NT levels (immunofluorescence) and reduced NO bioavailability(guanosine 3',5'-monophosphate (cGMP) production, EIA). Furthermore, immunohistochemistry revealed increased eNOS and NT immunoreactivity in GD umbilical cords. CONCLUSION: Endothelial cells exposed in vivo even transiently to hyperglycaemia, oxidative stress and inflammation exhibit durable pro-atherogenic modifications.


Assuntos
Diabetes Gestacional/patologia , Células Endoteliais da Veia Umbilical Humana/patologia , Cordão Umbilical/patologia , Doenças Vasculares/patologia , Adulto , Aterosclerose/patologia , Glicemia/metabolismo , Adesão Celular , AMP Cíclico/metabolismo , Feminino , Teste de Tolerância a Glucose , Homeostase , Humanos , Hiperglicemia/sangue , Leucócitos , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo III/metabolismo , Estresse Oxidativo , Gravidez , Tirosina/análogos & derivados , Tirosina/metabolismo , Doenças Vasculares/complicações
6.
Am J Primatol ; 75(9): 959-71, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23640681

RESUMO

In nonhuman primate social groups, dominance ranks are usually assigned to individuals based on outcomes of dyadic agonistic encounters. Multiple approaches have been used, but currently there is no consensus. One approach, David's Scores (DS), offers dual advantages of yielding cardinal scores that may in turn be used to compute hierarchical steepness. Here we correlate rank orders yielded by DS with those yielded by both the traditionally used I&SI approach and the recently proposed parametric Bayesian approach. We use six datasets for female macaques (three despotic and three tolerant groups), and 90 artificially generated datasets modeling macaque groups. We also use the artificial datasets to determine the impact of three characteristics (group size, interaction frequency, and directional asymmetry of aggression) on the magnitude of correlation coefficients, and assess the relative utility of two indices used to compute DS: Dij versus Pij. DS-based rank orders were strongly positively correlated with those yielded by the other two approaches for five out of the six macaque datasets, and for the majority of artificial datasets. Magnitudes of correlation coefficients were unrelated to group size or interaction frequency, but increased with directional asymmetry, suggesting methodological inconsistencies were more likely when dyads had more frequent reversals in directions of aggression. Finally, rank orders calculated using the Dij and Pij indices were similarly consistent with orders from other methods. We conclude that DS offers consistent estimates of rank orders, except perhaps in groups with very low levels of aggression asymmetry. In such "tolerant" groups, we suggest that the relatively greater methodological variability in rank orders may reflect behavioral characteristics of tolerant groups rather than computational inconsistencies between methods. We hypothesize that this quality may be quantified using posterior probability scores of Bayesian rank orders and may also index macaque social styles.


Assuntos
Macaca/fisiologia , Predomínio Social , Animais , Teorema de Bayes , Feminino , Modelos Logísticos , Macaca/genética , Modelos Biológicos , Análise Multivariada , Especificidade da Espécie
7.
Philos Trans R Soc Lond B Biol Sci ; 376(1819): 20190672, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33423632

RESUMO

Decision outcomes in unpredictable environments may not have exact known probabilities. Yet the predictability level of outcomes matters in decisions, and animals, including humans, generally avoid ambiguous options. Managing ambiguity may be more challenging and requires stronger cognitive skills than decision-making under risk, where decisions involve known probabilities. Here we compare decision-making in capuchins, macaques, orangutans, gorillas, chimpanzees and bonobos in risky and ambiguous contexts. Subjects were shown lotteries (a tray of potential rewards, some large, some small) and could gamble a medium-sized food item to obtain one of the displayed rewards. The odds of winning and losing varied and were accessible in the risky context (all rewards were visible) or partially available in the ambiguous context (some rewards were covered). In the latter case, the level of information varied from fully ambiguous (individuals could not guess what was under the covers) to predictable (individuals could guess). None of the species avoided gambling in ambiguous lotteries and gambling rates were high if at least two large rewards were visible. Capuchins and bonobos ignored the covered items and gorillas and macaques took the presence of potential rewards into account, but only chimpanzees and orangutans could consistently build correct expectations about the size of the covered rewards. Chimpanzees and orangutans combined decision rules according to the number of large visible rewards and the level of predictability, a process resembling conditional probabilities assessment in humans. Despite a low sample size, this is the first evidence in non-human primates that a combination of several rules can underlie choices made in an unpredictable environment. Our finding that non-human primates can deal with the uncertainty of an outcome when exchanging one food item for another is a key element to the understanding of the evolutionary origins of economic behaviour. This article is part of the theme issue 'Existence and prevalence of economic behaviours among non-human primates'.


Assuntos
Cebus/psicologia , Tomada de Decisões , Hominidae/psicologia , Macaca/psicologia , Recompensa , Incerteza , Animais , Especificidade da Espécie
8.
Biochim Biophys Acta ; 1794(2): 263-9, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19059501

RESUMO

The expression of recombinant proteins is known to induce a metabolic rearrangement in the host cell. We used aggregation-sensitive model systems to study the effects elicited in Escherichia coli cells by the aggregation of recombinant glutathione-S-transferase and its fusion with the green fluorescent protein that, according to the expression conditions, accumulate intracellularly as soluble protein, or soluble and insoluble aggregates. We show that the folding state of the recombinant protein and the complexity of the intracellular aggregates critically affect the cell response. Specifically, protein misfolding and aggregation induce changes in specific host proteins involved in lipid metabolism and oxidative stress, a reduction in the membrane permeability, as well as a rearrangement of its lipid composition. The temporal evolution of the host cell response and that of the aggregation process pointed out that the misfolded protein and soluble aggregates are responsible for the membrane modifications and the changes in the host protein levels. Interestingly, native recombinant protein and large insoluble aggregates do not seem to activate stress markers and membrane rearrangements.


Assuntos
Membrana Celular/fisiologia , Escherichia coli/enzimologia , Glutationa Transferase/metabolismo , Dobramento de Proteína , Proteínas Recombinantes de Fusão/biossíntese , Permeabilidade da Membrana Celular , Genes Reporter , Proteínas de Fluorescência Verde/genética , Lipídeos de Membrana/metabolismo , Estresse Oxidativo , Proteínas Recombinantes de Fusão/genética , Espectroscopia de Infravermelho com Transformada de Fourier , beta-Galactosidase/genética
9.
Sci Total Environ ; 691: 516-527, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31325852

RESUMO

European standards for the protection of forests from ozone (O3) are based on atmospheric exposure (AOT40) that is not always representative of O3 effects since it is not a proxy of gas uptake through stomata (stomatal flux). MOTTLES "MOnitoring ozone injury for seTTing new critical LEvelS" is a LIFE project aimed at establishing a permanent network of forest sites based on active O3 monitoring at remote areas at high and medium risk of O3 injury, in order to define new standards based on stomatal flux, i.e. PODY (Phytotoxic Ozone Dose above a threshold Y of uptake). Based on the first year of data collected at MOTTLES sites, we describe the MOTTLES monitoring station, together with protocols and metric calculation methods. AOT40 and PODY, computed with different methods, are then compared and correlated with forest-health indicators (radial growth, crown defoliation, visible foliar O3 injury). For the year 2017, the average AOT40 calculated according to the European Directive was even 5 times (on average 1.7 times) the European legislative standard for the protection of forests. When the metrics were calculated according to the European protocols (EU Directive 2008/50/EC or Modelling and Mapping Manual LTRAP Convention), the values were well correlated to those obtained on the basis of the real duration of the growing season (i.e. MOTTLES method) and were thus representative of the actual exposure/flux. AOT40 showed opposite direction relative to PODY. Visible foliar O3 injury appeared as the best forest-health indicator for O3 under field conditions and was more frequently detected at forest edge than inside the forest. The present work may help the set-up of further long-term forest monitoring sites dedicated to O3 assessment in forests, especially because flux-based assessments are recommended as part of monitoring air pollution impacts on ecosystems in the revised EU National Emissions Ceilings Directive.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/estatística & dados numéricos , Monitoramento Ambiental/métodos , Ozônio/análise , Conservação dos Recursos Naturais , Ecossistema , Agricultura Florestal , Florestas , Estômatos de Plantas
10.
Vet Comp Oncol ; 16(1): E202-E206, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29047203

RESUMO

Antibodies cross-reacting with homologue antigens in different species would be essential reagents for the development of comparative oncology studies. In comparison with conventional immunoglobulin Gs, recombinant nanobodies (single-domain variable regions of heavy-chain only antibodies of Camelidae origin) can be easily isolated in vitro and engineered into a variety of reagents with optimized characteristics for different research and clinical applications. We recovered an anti-human epidermal growth factor receptor 2 (anti-HER2) nanobody from a naïve llama library by direct panning on whole cells and expressed it fused to Fc and green fluorescent protein. These immunoreagents were assessed by flow cytometry and immunofluorescence with both human and canine cells overexpressing HER2 and its canine homologue dog epidermal growth factor receptor 2. The reported data illustrate the potential of using this class of antibodies in comparative oncology and suggest some development perspectives enabled by in vitro panning of pre-immune nanobody libraries.


Assuntos
Doenças do Cão/imunologia , Neoplasias/imunologia , Anticorpos de Domínio Único/imunologia , Animais , Camelídeos Americanos/imunologia , Reações Cruzadas/imunologia , Cães , Receptores ErbB/imunologia , Citometria de Fluxo , Imunofluorescência , Humanos , Neoplasias/veterinária , Receptor ErbB-2/imunologia
11.
J Clin Invest ; 97(8): 1795-803, 1996 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-8621762

RESUMO

Cyclopentenone prostaglandins (PGs) inhibit virus replication in several DNA and RNA virus models, in vitro and in vivo. In the present report we demonstrate that the cyclopentenone prostaglandins PGA(1) and PGJ(2) at nontoxic concentrations can dramatically suppress HIV-1 replication during acute infection in CEM-SS cells. PGs did not affect HIV-1 adsorption, penetration, reverse transcriptase activity nor viral DNA accumulation in HIV-1 infected cells. A dramatic reduction in HIV-1 mRNA levels was detected up to 48-72 h after infection (p.i.) in PG-treated cells, and HIV-1 protein synthesis was greatly reduced by a single PG-treatment up to 96 h p.i. Repeated PGA(1)-treatments were effective in protecting CEM-SS cells by the cytopathic effect of the virus, and in dramatically reducing HIV-1 RNA levels up to 7 d after infection. The antiviral effect was not mediated by alterations in the expression of alpha-, beta-, or gamma-interferon,TNFalpha, TNFbeta, IL6, and IL10 in HIV-infected CEM-SS cells. The fact that prostaglandins are used clinically in the treatment of several diseases, suggests a potential use of cyclopentenone PGs in the treatment of HIV-infection.


Assuntos
Antivirais/farmacologia , HIV-1/efeitos dos fármacos , Prostaglandina D2/análogos & derivados , Prostaglandinas A/farmacologia , Replicação Viral/efeitos dos fármacos , Sequência de Bases , Divisão Celular/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , DNA de Neoplasias/biossíntese , DNA de Neoplasias/efeitos dos fármacos , Expressão Gênica/efeitos dos fármacos , Transcriptase Reversa do HIV , HIV-1/fisiologia , Humanos , Interferons/biossíntese , Interleucinas/biossíntese , Linfotoxina-alfa/biossíntese , Dados de Sequência Molecular , Proteínas de Neoplasias/biossíntese , Proteínas de Neoplasias/efeitos dos fármacos , Oligonucleotídeos Antissenso/farmacologia , Prostaglandina D2/farmacologia , RNA Neoplásico/biossíntese , RNA Neoplásico/efeitos dos fármacos , RNA Viral/biossíntese , RNA Viral/efeitos dos fármacos , DNA Polimerase Dirigida por RNA/metabolismo , Linfócitos T , Células Tumorais Cultivadas , Fator de Necrose Tumoral alfa/biossíntese
12.
Environ Pollut ; 146(3): 648-58, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16889878

RESUMO

Ozone (O3) exposure at Italian background sites exceeds UN/ECE concentration-based critical levels (CLe(c)), if expressed in terms of AOT40. Yet the occurrence of adverse effects of O3 on forests and crops is controversial. Possible reasons include (i) ability of response indicators to provide an unbiased estimate of O3 effects, (ii) setting of current CLe(c) in terms of cut-off value and accumulation level, (iii) response functions adopted to infer a critical level, (iv) environmental limitation to O3 uptake and (v) inherent characteristics of Mediterranean vegetation. In particular, the two latter points suggest that critical levels based on accumulated stomatal flux (CLe(f)) can be a better predictor of O3 risk than CLe(c). While this concept is largely acknowledged, a number of factors may limit its applicability for routine monitoring. This paper reviews levels, uptake and vegetation response to O3 in Italy over recent years to discuss value, uncertainty and feasibility of different approaches to risk assessment.


Assuntos
Produtos Agrícolas/efeitos dos fármacos , Oxidantes Fotoquímicos/toxicidade , Ozônio/toxicidade , Árvores/efeitos dos fármacos , Produtos Agrícolas/metabolismo , Exposição Ambiental/efeitos adversos , Monitoramento Ambiental/métodos , Itália , Modelos Biológicos , Oxidantes Fotoquímicos/farmacocinética , Ozônio/farmacocinética , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/metabolismo , Medição de Risco/métodos , Árvores/metabolismo , Incerteza
13.
Sci Total Environ ; 556: 1-11, 2016 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-26971205

RESUMO

Ozone (O3) is both a greenhouse gas and a secondary air pollutant causing adverse impacts on forests ecosystems at different scales, from cellular to ecosystem level. Specifically, the phytotoxic nature of O3 can impair CO2 assimilation that, in turn affects forest productivity. This study aims to evaluate the effects of tropospheric O3 on Gross Primary Production (GPP) at 37 European forest sites during the time period 2000-2010. Due to the lack of carbon assimilation data at O3 monitoring stations (and vice-versa) this study makes a first attempt to combine high resolution MODIS Gross Primary Production (GPP) estimates and O3 measurement data. Partial Correlations, Anomalies Analysis and the Random Forests Analysis (RFA) were used to quantify the effects of tropospheric O3 concentration and its uptake on GPP and to evaluate the most important factors affecting inter-annual GPP changes. Our results showed, along a North-West/South-East European transect, a negative impact of O3 on GPP ranging from 0.4% to 30%, although a key role of meteorological parameters respect to pollutant variables in affecting GPP was found. In particular, meteorological parameters, namely air temperature (T), soil water content (SWC) and relative humidity (RH) are the most important predictors at 81% of test sites. Moreover, it is interesting to highlight a key role of SWC in the Mediterranean areas (Spanish, Italian and French test sites) confirming that, soil moisture and soil water availability affect vegetation growth and photosynthesis especially in arid or semi-arid ecosystems such as the Mediterranean climate regions. Considering the pivotal role of GPP in the global carbon balance and the O3 ability to reduce primary productivity of the forests, this study can help in assessing the O3 impacts on ecosystem services, including wood production and carbon sequestration.


Assuntos
Poluentes Atmosféricos/toxicidade , Monitoramento Ambiental , Florestas , Ozônio/toxicidade
14.
Biochim Biophys Acta ; 874(2): 181-6, 1986 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-3490880

RESUMO

Photo-chemically induced dynamic nuclear polarization (CIDNP)-NMR spectroscopy at 360 MHz has been used to investigate pH-induced conformational transitions in mouse epidermal growth factor. At about pH 9, all five tyrosine residues and both tryptophan residues are, to various extents, solvent-exposed, while the His-22 residue is buried in the protein matrix. Tyr-13 is the least exposed of the tyrosine residues and also the most immobilized. As the pH is decreased to 5.9, the tryptophan residues gradually become less exposed, while the Tyr-13 residue becomes internalized in the protein. These data suggest that the C-terminus and part of the N-terminal structural domain are affected by a conformational transition in mouse epidermal growth factor occurring between pH 6 and 8 via breakage of the His-22 inter-residue linkage. Above pH 9, a decreased photo-CIDNP effect is evident for both tryptophans and for Tyr-10 and Try-13; this information suggests that a second conformational change takes place at basic pH, which may simply be incipient denaturation.


Assuntos
Fator de Crescimento Epidérmico/metabolismo , Animais , Histidina , Concentração de Íons de Hidrogênio , Cinética , Espectroscopia de Ressonância Magnética/métodos , Camundongos , Conformação Proteica , Glândulas Salivares/metabolismo , Triptofano , Tirosina
15.
Biochim Biophys Acta ; 827(3): 369-80, 1985 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-2982407

RESUMO

1H-NMR Overhauser experiments at 300 and 600 MHz have been implemented on the isolated kringle 4 fragment of human plasminogen. This study shows that Leu46 and Leu77 CH3 delta,delta' groups, as well as two threonine CH3 gamma and a methionine S-CH epsilon (probably Met48) groups, are in efficient dipolar contact with histidine and aromatic side-chains. In particular, the experiments reveal that of the two Leu46 CH3 delta,delta' groups, one is in efficient contact with tryptophan (Trp25 and Trp62) indole rings while the other interacts with a tyrosine (probably Tyr41) phenol. Leu46 appears also to be close to an Ala CH3 beta group. Such a hydrophobic cluster appears to be contiguous to Trp72, hence to Arg71, residues that are through to be part of the lysine-binding site. Acid-base titration experiments show that the buried methionine S-CH3 epsilon group senses a neighboring ionizable group of pK*1 = 3.76, suggesting presence of a carboxyl anionic group (probably an aspartic acid side-chain) in the vicinity of the hydrophobic core. A preliminary model is proposed for the overall folding of the kringle polypeptide chain.


Assuntos
Fragmentos de Peptídeos/análise , Plasminogênio/análise , Sequência de Aminoácidos , Humanos , Espectroscopia de Ressonância Magnética , Matemática , Modelos Moleculares , Conformação Proteica
16.
Biochim Biophys Acta ; 994(2): 121-37, 1989 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-2535939

RESUMO

Photo-chemically induced dynamic nuclear polarization (photo-CIDNP) one-dimensional and two-dimensional (2D) 1H-NMR techniques have been applied to the study of the kringle 4 domain of human plasminogen both ligand-free and complexed to the antifibrinolytic drugs epsilon-aminocaproic acid and p-benzylaminesulfonic acid (BASA). A number of aromatic side-chains (His3, Trp72, Tyr41, Tyr50 and Tyr74) appear to be exposed and accessible to 3-N-carboxymethyl-lumiflavin, the photopolarizing flavin dye, both in the presence and in the absence of ligands. A lesser exposure is observed for the Trp25 and Trp62 indole groups in the presence of BASA. The spin-spin (J-coupling) and dipolar (Overhauser) connectivities in the 2D experiments afford absolute assignment of aromatic resonances for the above residues, as well as of those stemming from the Trp72 ring in the presence of BASA. Moreover, a number of H beta resonances can be identified and sorted according to specific types of amino acid residues.


Assuntos
Espectroscopia de Ressonância Magnética/métodos , Plasminogênio , Ácido Aminocaproico , Antifibrinolíticos , Benzilaminas , Histidina , Humanos , Técnicas In Vitro , Ligantes , Fenilalanina , Fotoquímica , Prótons , Triptofano , Tirosina
17.
Biochim Biophys Acta ; 707(1): 50-8, 1982 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-7138878

RESUMO

A new active form of porcine PSTI (pancreatic secretory trypsin inhibitor) was isolated during the fractionation by ion-exchange chromatography of the already known forms PSTI I and II. Biochemical and 1H-NMR techniques were used to characterize the new inhibitor, which is referred to as PSTI III. The amino acid composition, the nature of the N-terminal residue and data obtained from the tryptic peptides and indicate that PSTI III lacks the N-terminal octapeptide of PSTI I; hence, it starts and ends with disulfide bridges. The conclusion is supported by the 1H-NMR spectrum of the protein at 270 MHz. The biological activity and the most prominent conformational and dynamic features of forms I and II are retained in inhibitor III. However, PSTI III appears to be less compact than its parent forms I and II, suggesting that in the latter inhibitors an interaction between the N-terminal tail and the bulk of the protein may contribute to the overall stability. The genetic origin of PSTI III is discussed.


Assuntos
Pâncreas/análise , Inibidor da Tripsina Pancreática de Kazal/isolamento & purificação , Inibidores da Tripsina/isolamento & purificação , Sequência de Aminoácidos , Animais , Espectroscopia de Ressonância Magnética , Fragmentos de Peptídeos/análise , Suínos , Tripsina
18.
Genetics ; 92(1): 175-87, 1979 May.
Artigo em Inglês | MEDLINE | ID: mdl-115746

RESUMO

Experiments conducted on the X irradiation of neural ganglia of Drosophila melanogaster are described. The ganglia were placed in saline containing colchicine. After two hours, they were irradiated and then samples were fixed at 5,15,25,35 minutes from the beginning of irradiation. The results obtained show that the aberration level increases with time subsequent to fixing. This increase takes place first for chromatid deletions and then for isochromatid deletions and chromatid exchanges. Gaps and subchromatid exchanges do not, on the contrary, show any increase with time. We did not observe a difference in radiosensitivity between the sexes. Some hypotheses are put forth in an attempt to explain these results.


Assuntos
Ciclo Celular , Aberrações Cromossômicas , Cromossomos/efeitos da radiação , Drosophila melanogaster/genética , Metáfase , Animais , Gânglios/citologia , Gânglios/ultraestrutura , Fatores de Tempo , Raios X
19.
Plant Physiol ; 110(1): 137-145, 1996 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-12226176

RESUMO

Total peroxidase, NADH-peroxidase, ascorbate peroxidase, superoxide dismutase, and catalase activities were measured in tobacco (Nicotiana tabacum) leaves and in regenerating and nonregenerating protoplasts isolated from the same tissue and cultured for 2 weeks. The specific ranges of H2O2 concentration at which the enzymes scavenging the active forms of oxygen may efficiently operate and the activities of those enzymes were determined in an extract from tobacco leaves and in dividing and nondividing tobacco mesophyll protoplasts. The overall H2O2-scavenging enzyme activities were similar in both protoplast populations during the 2 to 3 d of culture. After 3 d, the regenerating protoplasts started to divide and both the antioxidant enzyme activities and the total peroxidase activity increased; in contrast, the viability and the H2O2-scavenging enzyme activities in nonregenerating protoplasts dramatically decreased. Surprisingly, the regenerative potentiality in dividing protoplasts was specifically correlated with a higher NADH-peroxidase activity, which resulted in a net H2O2 accumulation in the cells. Light, which causes the accumulation of active forms of oxygen in photosynthetic organelles, also stimulated catalase and ascorbate peroxidase activities in dividing protoplasts. We suggest that the localization of H2O2 rather than its absolute concentration might be responsible for oxidative stress and that controlled amounts of H2O2 are necessary to allow proper cell-wall reconstitution and the consequent cell division.

20.
Environ Mol Mutagen ; 46(3): 182-8, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16206220

RESUMO

The genotoxic effects associated with automobile painting were analyzed using a panel of biomarkers. Chromosomal aberrations (CAs), sister chromatid exchange (SCE), and micronuclei were evaluated in 25 car painters (12 smokers, 13 nonsmokers) working in different automobile paint-shops in Italy and in 37 control subjects. The controls were healthy blood donors (14 smokers, 23 non-smokers) that were matched with the experimental population for gender and age. Air samples were analyzed regularly at the work places, and elevated concentrations of benzene and toluene were detected consistently. The exposed group had higher frequencies of CAs (both chromosome- and chromatid-type), micronuclei, and SCE (P < 0.5 - P < 0.001). Furthermore, exposed and control subjects were also genotyped for GSTM1 and GSTT1 polymorphism. No significant associations were detected between the biomarker responses and either the GSTM1 or GSTT1 genotype of the subjects, but the small sample size does not allow definite conclusions on the relationship between the genetic polymorphism and the biomarkers. The results indicate that automobile painters have increased levels of clastogenic and possible aneugenic damage and that smoking may be a confounding factor for the responses.


Assuntos
Biomarcadores , Aberrações Cromossômicas , Cromossomos/efeitos dos fármacos , Dano ao DNA , Adulto , Automóveis , Benzeno/química , Estudos de Casos e Controles , DNA/efeitos dos fármacos , Genótipo , Glutationa Transferase/genética , Homozigoto , Humanos , Indústrias , Itália , Linfócitos/citologia , Linfócitos/efeitos dos fármacos , Masculino , Testes para Micronúcleos , Pessoa de Meia-Idade , Mutagênicos/química , Exposição Ocupacional , Polimorfismo Genético , Troca de Cromátide Irmã , Fumar , Tolueno/química
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