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2.
G Ital Nefrol ; 35(6)2018 Dec.
Artigo em Italiano | MEDLINE | ID: mdl-30550044

RESUMO

The article deals with the regulatory and jurisprudential evolution of medical criminal responsibility from the 70s to the Gelli-Bianco law of 2017. Subsequently it winds through the contribution of the last important judgments of the subject up to the decisions of the Supreme Court with United Sections of 2018, finally to conclude with an economic analysis on the increasement of the legal disputes registered in recent years.


Assuntos
Crime/legislação & jurisprudência , Legislação Médica , Responsabilidade Legal , Crime/economia , Crime/história , História do Século XX , História do Século XXI , Itália , Legislação Médica/economia , Legislação Médica/história , Legislação Médica/tendências , Responsabilidade Legal/economia , Imperícia/economia , Imperícia/legislação & jurisprudência , Guias de Prática Clínica como Assunto , Punição
3.
Mar Genomics ; 2(1): 1-10, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21798166

RESUMO

The present review surveys several recent studies of the aspartic proteinases from Antarctic Notothenioidei, a dominating fish group that has developed a number of adjustments at the molecular level to maintain metabolic function at low temperatures. Given the unique peculiarities of the Antarctic environment, studying the features of Antarctic aspartic proteinases could provide new insights into the role of these proteins in fish physiology. We describe here: (1) the biochemical properties of a cathepsin D purified from the liver of the hemoglobinless icefish Chionodraco hamatus; (2) the biochemical characterization of Trematomus bernacchii pepsins variants A1 and A2 obtained by heterologous expression in bacteria; and (3) the identification of two closely related, novel aspartic proteinases from the liver of the two Antarctic fish species mentioned above. Overall, the results show that Notothenioidei aspartic proteinases display a number of characteristics that are remarkably different from those of mammalian aspartic proteinases, including high turnover number or high catalytic efficiency. We have named the newly identified aspartic proteinases "Nothepsins" and classified them relative to aspartic proteinases from other species.

4.
FEBS J ; 274(23): 6152-66, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17976195

RESUMO

The Antarctic notothenioid Trematomus bernacchii (rock cod) lives at a constant mean temperature of -1.9 degrees C. Gastric digestion under these conditions relies on the proteolytic activity of aspartic proteases such as pepsin. To understand the molecular mechanisms of Antarctic fish pepsins, T. bernacchii pepsins A1 and A2 were cloned, overexpressed in Escherichia coli, purified and characterized with a number of biochemical and biophysical methods. The properties of these two Antarctic isoenzymes were compared to those of porcine pepsin and found to be unique in a number of ways. Fish pepsins were found to be more temperature sensitive, generally less active at lower pH and more sensitive to inhibition by pepstatin than their mesophilic counterparts. The specificity of Antarctic fish pepsins was similar but not identical to that of pig pepsin, probably owing to changes in the sequence of fish enzymes near the active site. Gene duplication of Antarctic rock cod pepsins is the likely mechanism for adaptation to the harsh temperature environment in which these enzymes must function.


Assuntos
Isoenzimas/química , Isoenzimas/isolamento & purificação , Pepsina A/química , Pepsina A/isolamento & purificação , Perciformes/metabolismo , Sequência de Aminoácidos , Animais , Regiões Antárticas , Sítios de Ligação , Clonagem Molecular , Precursores Enzimáticos/metabolismo , Estabilidade Enzimática , Escherichia coli/genética , Mucosa Gástrica/enzimologia , Concentração de Íons de Hidrogênio , Corpos de Inclusão/metabolismo , Isoenzimas/antagonistas & inibidores , Isoenzimas/genética , Isoenzimas/metabolismo , Cinética , Modelos Moleculares , Dados de Sequência Molecular , Peso Molecular , Pepsina A/antagonistas & inibidores , Pepsina A/genética , Pepsina A/metabolismo , Pepstatinas/farmacologia , Perciformes/genética , Inibidores de Proteases/farmacologia , Ligação Proteica , Dobramento de Proteína , Estrutura Secundária de Proteína , Proteínas Recombinantes/química , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/metabolismo , Homologia de Sequência de Aminoácidos , Solubilidade , Especificidade por Substrato , Suínos , Temperatura
5.
Biochim Biophys Acta ; 1769(4): 228-35, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17475349

RESUMO

Citrus are natural hosts of several viroids, which are plant pathogens composed exclusively of a non-protein-coding, small single-stranded circular RNA that is able to replicate autonomously in susceptible hosts. They are responsible for symptoms such as stunting, leaf epinasty, and chlorosis. Citrus viroid III (CVd-III) has been long regarded as a possible dwarfing agent of citrus grafted on trifoliate orange and its hybrids. To investigate molecular mechanisms involved in pathogenesis, the messenger RNA (mRNA) differential display technique was here applied to identify genes whose transcription was significantly altered in leaves of Etrog citron (Citrus medica) infected by CVd-III (variant b). Of eighteen genes identified, thirteen were up-regulated by viroid infection, while five were down-regulated. Except for two genes that encode proteins of unknown function, the remaining genes are mainly involved in plant defence/stress responses, signal transduction, amino acid transport, and cell wall structure. Among the up-regulated genes, it is noteworthy a suppressor of RNA silencing that might be involved in viroid and virus pathogenicity. The functions of these genes are discussed.


Assuntos
Citrus/genética , Citrus/virologia , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Doenças das Plantas/genética , Doenças das Plantas/imunologia , Doenças das Plantas/virologia , Folhas de Planta/genética , Folhas de Planta/virologia , Vírus de Plantas/patogenicidade , RNA de Plantas/análise , Transdução de Sinais/genética , Viroides/patogenicidade
6.
Extremophiles ; 10(5): 393-402, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16636888

RESUMO

The archaeon Aeropyrum pernix grows optimally at 90 degrees C and derives energy primarily from aerobic degradation of complex proteinaceous substrates. The ability of these nutrients to sustain growth is generally associated with the presence of oligopeptide transport systems, such as the well-known protein-dependent ATP-binding cassette (ABC) transporters. This study is concerned with the isolation and characterisation of the first archaeal oligopeptide-binding protein (OppA(Ap)) from the extracellular medium of A. pernix. The protein shows a pI of 3.9 and a molecular mass of about 90 kDa under native conditions. By using a proteomic approach, the OppA(Ap)-encoding gene was identified (APE1583) and about 55% of the protein amino-acid sequence was validated. The extracellular purified protein was able to efficiently bind oligopeptide substrates such as Xenopsin. The amount of a liganded peptide to OppA(Ap) was about 70% at 90 degrees C using a 1/100 (w/w) OppA(Ap)/substrate ratio. Sequence comparisons showed a weak but significant similarity of OppA(Ap) with bacterial oligopeptide binding proteins. Furthermore, APE1583 neighbouring genes encode for the cognate components of an ABC transport system, suggesting that these ORFs are organised in an operon-like structure, with OppA(Ap )as the extracellular component for the uptake of oligopeptides.


Assuntos
Aeropyrum/metabolismo , Proteínas Arqueais/isolamento & purificação , Proteínas de Transporte/isolamento & purificação , Transportadores de Cassetes de Ligação de ATP/genética , Transportadores de Cassetes de Ligação de ATP/isolamento & purificação , Transportadores de Cassetes de Ligação de ATP/metabolismo , Aeropyrum/genética , Aeropyrum/crescimento & desenvolvimento , Sequência de Aminoácidos , Proteínas Arqueais/genética , Proteínas Arqueais/metabolismo , Proteínas de Bactérias/genética , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Genes Arqueais , Genoma Arqueal , Temperatura Alta , Ponto Isoelétrico , Dados de Sequência Molecular , Peso Molecular , Oligopeptídeos/metabolismo , Mapeamento de Peptídeos , Proteômica
7.
Gene ; 356: 153-9, 2005 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-16000247

RESUMO

Bryophytes are valuable bioaccumulators, because they have high absorbing and ion exchange capacities. Cadmium (Cd) is a heavy metal naturally present in soil; it is non-essential and highly toxic to most organisms, having toxicity 2 to 20 times higher than many other heavy metals. The presence of elevated levels of Cd ions triggers a wide range of cellular responses including changes in gene expression and synthesis of metal-detoxifying peptides. To investigate the ability of Cd to affect gene transcription, the messenger RNA (mRNA) differential display technique was applied to the identification and isolation of genes whose transcription was altered in cultured Lunularia cruciata plants that were grown in the presence of cadmium salts. Four genes whose mRNA levels significantly changed in response to cadmium exposure were isolated and identified. The first gene identified in our analysis is up-regulated by Cd: it encodes the enzyme cystathionine gamma-synthase. The other genes are down-regulated by cadmium. These genes encode a methyltransferase, a tyrosine phosphatase and the EST 408 of the diatom Fragilariopsis cylindrus, whose function is unknown. Our findings demonstrate the usefulness of mRNA differential display technique for the detection of plant metabolic pathways affected by cadmium stress.


Assuntos
Cádmio/farmacologia , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Hepatófitas/efeitos dos fármacos , Northern Blotting , Carbono-Oxigênio Liases/genética , DNA Complementar/química , DNA Complementar/genética , Regulação para Baixo/efeitos dos fármacos , Regulação para Baixo/genética , Perfilação da Expressão Gênica , Hepatófitas/genética , Metiltransferases/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de DNA , Regulação para Cima/efeitos dos fármacos , Regulação para Cima/genética
8.
Acta Paediatr ; 94(2): 197-200, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15981754

RESUMO

AIM: To compare, in a prospective clinical trial, oxygen delivery on intermittent positive pressure with nasal cannulae versus facial mask in primary resuscitation of the newborn with moderate asphyxia. METHODS: 617 neonates with moderate asphyxia at birth were randomized: 303 were resuscitated by oxygen on intermittent positive pressure with nasal cannuale and 314 neonates by mask. Resuscitation followed the Neonatal Resuscitation Program guidelines of the American Academy of Pediatrics, 3rd edition. RESULTS: Resuscitation through the nasal route less frequently requires chest compressions and intubations (26 neonates needed chest compression and 20 needed intubation out of 314 resuscitated by mask; five neonates needed chest compression and two needed intubation out of 303 resuscitated by nasal cannulae). Apgar scores, admission rates to neonatal intensive care units, air-leak syndromes, birthweight, gestational age, use of prenatal steroids and deaths did not differ between groups. CONCLUSION: Oxygen delivery on intermittent positive pressure with nasal cannulae in primary resuscitation of the newborn with moderate asphyxia is a less aggressive and potentially advantageous alternative to the traditional oral route.


Assuntos
Asfixia Neonatal/terapia , Respiração com Pressão Positiva Intermitente/instrumentação , Ressuscitação/instrumentação , Análise de Variância , Feminino , Humanos , Recém-Nascido , Respiração com Pressão Positiva Intermitente/métodos , Masculino , Máscaras , Cavidade Nasal , Ressuscitação/métodos
9.
Gene ; 338(2): 225-33, 2004 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-15315826

RESUMO

Copper and iron act at different levels on gene expression. Due to their chemical reactivity, both metals could play a role in the regulation of the protein machinery involved in their metabolism, and/or of the metabolic function they are involved in. Experimental and clinical evidences raise also the hypothesis of the existence of genes commonly regulated by both metals. Purpose of this work was to find genes modulated by copper and iron in the rat intestine. A panel of 24 animals was randomly divided into three nutritional treatments including a control, a copper-deficient and an iron-deficient diet. The positive regulation of iron responsive element (IRE)-DMT1 gene was found, with different extent, in both experimental groups. A differential display reverse transcription (DDRT)-polymerase chain reaction (PCR) analysis carried out on the rat intestinal mRNAs demonstrated the differential expression of five cDNA fragments. Among these, the Cytochrome c oxidase (COX) subunit II mitochondrial gene resulted to be regulated by both metals, the Serum and Glucocorticoids-regulated Kinase (SGK) gene mainly by iron, and an Ebnerin-like 2 kb mRNA dramatically down-regulated by copper. Two residual clones showed low identity scores with sequences present in data bank. Finally, we observed that both iron and copper are able to modulate the expression of the three characterized genes in some tissues, other than intestine.


Assuntos
Cobre/administração & dosagem , Regulação da Expressão Gênica/efeitos dos fármacos , Mucosa Intestinal/metabolismo , Ferro/administração & dosagem , Animais , Northern Blotting , Proteínas de Transporte de Cátions/genética , Cobre/análise , Cobre/deficiência , Dieta , Complexo IV da Cadeia de Transporte de Elétrons/genética , Perfilação da Expressão Gênica , Proteínas Imediatamente Precoces , Intestinos/química , Ferro/análise , Deficiências de Ferro , Proteínas de Ligação ao Ferro/genética , Fígado/química , Fígado/metabolismo , Masculino , Proteínas Nucleares/genética , Proteínas Serina-Treonina Quinases/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Receptores Imunológicos/genética , Receptores Depuradores , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Desmame
10.
Gene ; 332: 29-34, 2004 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-15145051

RESUMO

The messenger RNA (mRNA) differential display technique was applied to the identification and isolation of genes whose transcription was altered in leaves of Prunus armeniaca infected by European stone fruit yellows (ESFY) phytoplasma belonging to ribosomal subgroup 16SrX-B. Four genes whose steady-state levels of expression significantly changed in response to phytoplasma infection were isolated and identified. The results obtained show that two group of genes are affected by phytoplasma infection in apricot leaves. The first group comprises genes that are up-regulated by phytoplasma presence: in particular, a gene encoding the heat-shock protein HSP-70, a gene encoding a metallothionein (MT) and another homologous to the EST 673 cDNA clone of P. armeniaca, whose function was unknown. The other gene identified in our analysis is down-regulated by phytoplasma presence. It encodes a protein having homology to an amino acid transporter of Arabidopsis thaliana. Our findings demonstrate the usefulness of mRNA differential display approach for the detection of plant metabolic pathways affected by phytoplasma infection.


Assuntos
Perfilação da Expressão Gênica , Phytoplasma/crescimento & desenvolvimento , Folhas de Planta/genética , Prunus/genética , RNA Mensageiro/genética , Northern Blotting , DNA Complementar/química , DNA Complementar/genética , DNA Complementar/isolamento & purificação , Regulação da Expressão Gênica de Plantas , Folhas de Planta/microbiologia , Prunus/microbiologia , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de DNA
11.
Biol Neonate ; 83(3): 197-200, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12660438

RESUMO

UNLABELLED: Neonatal polycythemia is a potentially lethal, multi-organ disease. We have performed a prospective, open-label study to test the hypothesis that an early cord clamping proximally to the neonate's abdomen could avert from the neonatal circulation a blood volume critical to the occurrence of polycythemia in at-risk neonates. Newborns were divided into group 1 (clamping time within 10 s) and group 2 (clamping time 11-120 s). Group 1 had statistically significant more blood volume sequestered in the cord and less manifestations of polycythemia. CONCLUSION: An early cord clamping is an effective and zero-cost way to prevent polycythemia in at-risk neonates.


Assuntos
Constrição , Policitemia/prevenção & controle , Cordão Umbilical , Volume Sanguíneo , Humanos , Recém-Nascido , Estudos Prospectivos , Fatores de Tempo , Cordão Umbilical/irrigação sanguínea
12.
J Neuropathol Exp Neurol ; 61(10): 841-8, 2002 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12387450

RESUMO

Chorea-Acanthocytosis (CHAC) is an autosomal recessive disease characterized by neurodegeneration and acanthocytosis. Enhanced creatine kinase concentration is a constant feature of the condition. The mechanism underlying CHAC is unknown. However, acanthocytosis and enhanced creatine kinase suggest a protein defect that deranges the membrane-cytoskeleton interface in erythrocytes and muscle, thereby resulting in neurodegeneration. Acanthocytes have been correlated with structural and functional changes in membrane protein band 3--a ubiquitous anion transporter. Residue Gln-30 of band 3 serves as a membrane substrate for tissue transglutaminase (tTGase), which belongs to a class of intra- and extra-cellular Ca2+-dependent cross-linking enzymes found in most vertebrate tissues. In an attempt to cast light on the pathophysiology of CHAC, we used reverse-phase HPLC and immunohistochemistry to evaluate the role of tTGase in this disorder. We found increased amounts of tTGase-derived N(epsilon)-(-gamma-glutamyl)lysine isopeptide cross-links in erythrocytes and muscle from CHAC patients. Furthermore, immunohistochemistry demonstrated abnormal accumulation of tTGase products as well as proteinaceous bodies in CHAC muscles. These findings could explain the mechanisms underlying the increased blood levels of creatine kinase and acanthocytosis, which are the most consistent features of this neurodegenerative disease.


Assuntos
Coreia/enzimologia , Eritrócitos/enzimologia , Proteínas de Ligação ao GTP/metabolismo , Músculo Esquelético/enzimologia , Transglutaminases/metabolismo , Coreia/sangue , Coreia/patologia , Reagentes de Ligações Cruzadas , Eritrócitos/patologia , Eritrócitos/ultraestrutura , Proteínas de Ligação ao GTP/sangue , Humanos , Isoenzimas/sangue , Isoenzimas/metabolismo , Microscopia Eletrônica , Músculo Esquelético/patologia , Músculo Esquelético/ultraestrutura , Mapeamento de Peptídeos , Proteína 2 Glutamina gama-Glutamiltransferase , Transglutaminases/sangue
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