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1.
Heliyon ; 10(8): e29356, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38644898

RESUMO

Landfills play a key role as greenhouse gas (GHGs) emitters, and urgently need assessment and management plans development to swiftly reduce their climate impact. In this context, accurate emission measurements from landfills under different climate and management would reduce the uncertainty in emission accounting. In this study, more than one year of long-term high-frequency data of CO2 and CH4 fluxes were collected in two Italian landfills (Giugliano and Case Passerini) with contrasting management (gas recovery VS no management) using eddy covariance (EC), with the aim to i) investigate the relation between climate drivers and CO2 and CH4 fluxes at different time intervals and ii) to assess the overall GHG balances including the biogas extraction and energy recovery components. Results indicated a higher net atmospheric CO2 source (5.7 ± 5.3 g m2 d-1) at Giugliano compared to Case Passerini (2.4 ± 4.9 g m2 d-1) as well as one order of magnitude higher atmospheric CH4 fluxes (6.0 ± 5.7 g m2 d-1 and 0.7 ± 0.6 g m2 d-1 respectively). Statistical analysis highlighted that fluxes were mainly driven by thermal variables, followed by water availability, with their relative importance changing according to the time-interval considered. The rate of change in barometric pressure (dP/dt) influenced CH4 patterns and magnitude in the classes ranging from -1.25 to +1.25 Pa h-1, with reduction when dP/dt > 0 and increase when dP/dt < 0, whilst a clear pattern was not observed when all dP/dt classes were analyzed. When including management, the total atmospheric GHG balance computed for the two landfills of Giugliano and Case Passerini was 174 g m2 d-1 and 79 g m2 d-1 respectively, of which 168 g m2 d-1 and 20 g m2 d-1 constituted by CH4 fluxes.

2.
Plant Biol (Stuttg) ; 25(4): 518-528, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36942418

RESUMO

Rising daily temperatures and water shortage are two of the major concerns in agriculture. In this work, we analysed the tolerance traits in a tomato line carrying a small region of the Solanum pennellii wild genome (IL12-4-SL) when grown under prolonged conditions of single and combined high temperature and water stress. When exposed to stress, IL12-4-SL showed higher heat tolerance than the cultivated line M82 at morphological, physiological, and biochemical levels. Moreover, under stress IL12-4-SL produced more flowers than M82, also characterized by higher pollen viability. In both lines, water stress negatively affected photosynthesis more than heat alone, whereas the combined stress did not further exacerbate the negative impacts of drought on this trait. Despite an observed decrease in carbon fixation, the quantum yield of PSII linear electron transport in IL12-4-SL was not affected by stress, thereby indicating that photochemical processes other than CO2 fixation acted to maintain the electron chain in oxidized state and prevent photodamage. The ability of IL12-4-SL to tolerate abiotic stress was also related to the intrinsic ability of this line to accumulate ascorbic acid. The data collected in this study clearly indicate improved tolerance to single and combined abiotic stress for IL12-4-SL, making this line a promising one for cultivation in a climate scenario characterized by frequent and long-lasting heatwaves and low rainfall.


Assuntos
Solanum lycopersicum , Solanum , Solanum lycopersicum/genética , Solanum/genética , Desidratação , Estresse Fisiológico/genética , Interleucina-12
3.
Plant Biol (Stuttg) ; 24(1): 62-74, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34605594

RESUMO

Climate change is increasing the frequency of high temperature shocks and water shortages, pointing to the need to develop novel tolerant varieties and to understand the mechanisms employed to withstand combined abiotic stresses. Two tomato genotypes, a heat-tolerant Solanum lycopersicum accession (LA3120) and a novel genotype (E42), previously selected as a stable yielding genotype under high temperatures, were exposed to single and combined water and heat stress. Plant functional traits, pollen viability and physiological (leaf gas exchange and chlorophyll a fluorescence emission measurements) and biochemical (antioxidant content and antioxidant enzyme activity) measurements were carried out. A Reduced Representation Sequencing approach allowed exploration of the genetic variability of both genotypes to identify candidate genes that could regulate stress responses. Both abiotic stresses had a severe impact on plant growth parameters and on the reproductive phase of development. Growth parameters and leaf gas exchange measurements revealed that the two genotypes used different physiological strategies to overcome individual and combined stresses, with E42 having a more efficient capacity to utilize the limiting water resources. Activation of antioxidant defence mechanisms seemed to be critical for both genotypes to counteract combined abiotic stresses. Candidate genes were identified that could explain the different physiological responses to stress observed in E42 compared with LA3120. Results here obtained have shown how new tomato genetic resources can be a valuable source of traits for adaptation to combined abiotic stresses and should be used in breeding programmes to improve stress tolerance in commercial varieties.


Assuntos
Solanum lycopersicum , Clorofila A , Genótipo , Resposta ao Choque Térmico/genética , Solanum lycopersicum/genética , Estresse Fisiológico/genética , Água
4.
Sci Total Environ ; 408(7): 1508-14, 2010 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-20092872

RESUMO

This study investigated whether overlaying organic wastes directly on limestone debris allowed the growth of sclerophyllous shrubs; the aim was to explore the feasibility of rehabilitation of sites destroyed by quarrying activity. In an open air mesocosm experiment two types of organic material were compared: compost from municipal wastes (C) and a mixture of compost and poultry manure added with wheat husk (C-PW). Mesocosms were pots (1m diameter, 60cm height) containing limestone debris covered by the organic material. Seven mesocosms with C and seven mesocosms with C-PW were planted with sclerophyllous shrubs (Laurus nobilis L., Phillyrea angustifolia L. and Quercus ilex L.). The substrates were characterised in terms of chemical and physical parameters, microbial activity and biomass, and total and active fungal biomass. Shrub photosynthetic performance and growth were evaluated. Over the whole experimental period, organic matter mineralization was higher in C-PW. Microbial biomass and respiration were higher in C-PW than in C but after one year no statistically significant difference between the two substrates occurred. Fungal mycelium was a minor fraction of the microbial community in both types of substrates and decreased dramatically after setting up the mesocosms. The metabolic quotient was higher in C suggesting more stressful conditions as compared to C-PW. Both substrates allowed shrub growth; however photosynthetic rates and the increase of plant size were higher on C-PW than on C. The results demonstrated that, as compared to only compost, the mixture of compost and poultry manure added with wheat husk is a substrate more suitable to both microbial processes and plant growth. Therefore a plan to revegetate quarries based on the use of organic wastes as a substrate for sclerophyllous shrubs could be feasible and, what is more, helpful to mitigate the environmental impact of organic wastes disposal.


Assuntos
Carbonato de Cálcio , Ecossistema , Compostos Orgânicos , Desenvolvimento Vegetal
5.
Plant Biol (Stuttg) ; 10(2): 194-201, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18304193

RESUMO

We assessed the contribution of leaf movements to PSII photoprotection against high light and temperature in Robinia pseudoacacia. Gas exchange and chlorophyll a fluorescence measurements were performed during the day at 10:00, 12:00, 15:00 and 18:00 hours on leaves where paraheliotropic movements were restrained (restrained leaves, RL) and on control unrestrained leaves (UL). RL showed a strong decrease of net photosynthesis (A(n)), stomatal conductance (g(sH2O)), quantum yield of electron transport (PhiPSII), percentage of photosynthesis inhibited by O2 (IPO) and photochemical quenching (q(P)) in the course of the day, whereas, a significant increase in C(i)/C(a) and NPQ was observed. Contrary to RL, UL had higher photosynthetic performance that was maintained at elevated levels throughout the day. In the late afternoon, A(n), g(sH2O), PhiPSII and q(P) of RL showed a tendency to recovery, as compared to 15:00 hours, even if the values remained lower than those measured at 10:00 hours and in UL. In addition, contrary to UL, no recovery was found in F(v)/F(m) at the end of the study period in RL. Data presented suggest that in R. pseudoacacia, leaf movements, by reducing light interception, represent an efficient, fast and reversible strategy to overcome environmental stresses such as high light and temperature. Moreover, paraheliotropism was able to protect photosystems, avoiding photoinhibitory damage, leading to a carbon gain for the plant.


Assuntos
Fotossíntese/fisiologia , Robinia/metabolismo , Clorofila/metabolismo , Luz , Robinia/efeitos da radiação , Temperatura
6.
Ann Hum Genet ; 68(Pt 6): 546-54, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15598213

RESUMO

Down Syndrome (DS) is caused by the presence of three copies of the whole human chromosome 21 (HC21) or of a HC21 restricted region; the phenotype is likely to have originated from the altered expression of genes in the HC21. We apply the cDNA microarray method to the study of gene expression in human T lymphocytes with trisomy 21 in comparison to normal cells. Two patients with DS were investigated, along with two normal subjects as a control, all being tested in independent, duplicated cell culture experiments. The most consistent finding was the overexpression of the superoxide dismutase gene (SOD1), located on 21q, and of MHC DR beta 3 (HLA-DRB3), GABA receptor A gamma 2 (GABRG2), acetyltransferase Coenzyme, A 2 (ACAT2) and ras suppressor protein 1 (RSU1) genes. When the data were clustered according to chromosome localization, the HC21 gene set showed, on average, the highest expression in DS cells in all the experiments. Moreover, separate clustering of patients and controls was obtained when analysis was restricted to HC21 gene expression values. These findings reinforce the specific gene dosage theory for the pathogenesis of the DS phenotype, and show a consistent overexpression of the SOD1 gene on 21q.


Assuntos
Síndrome de Down/genética , Expressão Gênica/fisiologia , Linfócitos T/metabolismo , Síndrome de Down/metabolismo , Citometria de Fluxo , Perfilação da Expressão Gênica , Humanos , Análise de Sequência com Séries de Oligonucleotídeos
7.
Bioinformatics ; 20(16): 2883-5, 2004 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-15145799

RESUMO

UNLABELLED: Extracting the desired data from a database entry for later analysis is a constant need in the biological sequence analysis community; GeneRecords 1.0 is a solution for GenBank biological flat file parsing, as it implements a structured representation of each feature and feature qualifier in GenBank following import in a common database managing system usable in a personal computer (Macintosh and Windows environments). This collection of related databases enables the local management of GenBank records, allowing indexing, retrieval and analysis of both information and sequences on a personal computer. AVAILABILITY: The current release, including the FileMaker Pro runtime application (built for Windows and Macintosh environments), is freely available at http://apollo11.isto.unibo.it/software/


Assuntos
Sistemas de Gerenciamento de Base de Dados , Bases de Dados Genéticas , Documentação/métodos , Armazenamento e Recuperação da Informação/métodos , Microcomputadores , Análise de Sequência/métodos , Interface Usuário-Computador , Software
9.
J Immunol ; 167(11): 6303-11, 2001 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-11714794

RESUMO

The high-affinity IgG receptor, FcgammaRI (CD64), is constitutively expressed exclusively on professional APCs. Human FcgammaRI binds monomeric IgG with high affinity and is, therefore, saturated in vivo. The binding of IgG to FcgammaRI causes receptor recycling, while Abs that cross-link FcgammaRI cause rapid down-modulation of surface FcgammaRI. Because studies performed in the absence of ligand may not be representative of FcgammaRI modulation in vivo, we investigated the ability of FcgammaRI-cross-linking Abs and non-cross-linking derivatives to modulate FcgammaRI in the presence and absence of ligand. In the absence of ligand mAb H22 and wH22xeGFP, an enhanced green fluorescent protein (eGFP)-labeled fusion protein of H22, cross-linked and rapidly down-modulated surface FcgammaRI on the human myeloid cell line, U937, and its high FcgammaRI-expressing subclone, 10.6. This effect was dependent on the concentration of fusion protein and the level of FcgammaRI expression and correlated with internalization of both wH22xeGFP and FcgammaRI, itself, as assessed by confocal microscopy. A single-chain Fv version, sFv22xeGFP, which does not cross-link FcgammaRI, was unable to modulate FcgammaRI in the absence of IgG. However, if ligand was present, treatment with either monovalent or cross-linking fusion protein led to intracellular receptor accumulation. These findings suggest at least two alternate mechanisms of internalization that are influenced by ligand and demonstrate the physiologic potential of FcgammaRI to transport a large antigenic load into APCs for processing. These studies may lead to the development of better FcgammaRI-targeted vaccines, as well as therapies to down-modulate FcR involved in autoimmune diseases.


Assuntos
Adjuvantes Imunológicos/farmacologia , Imunoglobulina G/farmacologia , Receptores de IgG/genética , Receptores de IgG/metabolismo , Proteínas Recombinantes de Fusão/imunologia , Proteínas Recombinantes de Fusão/metabolismo , Adjuvantes Imunológicos/biossíntese , Adjuvantes Imunológicos/genética , Adjuvantes Imunológicos/metabolismo , Anticorpos Monoclonais/genética , Anticorpos Monoclonais/metabolismo , Anticorpos Monoclonais/farmacologia , Sítios de Ligação de Anticorpos/genética , Células Clonais , Relação Dose-Resposta Imunológica , Regulação para Baixo/genética , Regulação para Baixo/imunologia , Vetores Genéticos/metabolismo , Vetores Genéticos/farmacologia , Proteínas de Fluorescência Verde , Humanos , Líquido Intracelular/imunologia , Líquido Intracelular/metabolismo , Ligantes , Proteínas Luminescentes/genética , Proteínas Luminescentes/metabolismo , Modelos Imunológicos , Receptores de IgG/biossíntese , Receptores de IgG/imunologia , Proteínas Recombinantes de Fusão/farmacologia , Células U937
10.
Eur J Biochem ; 268(14): 3964-73, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11453990

RESUMO

In a series of four racemic phenoxyalkyl-alkyl carbinols, 1-phenoxy-2-hydroxybutane (1) is enantioselectively acetylated by Burkholderia cepacia (formerly Pseudomonas cepacia) lipase with an E value > or = 200, whereas for the other three racemates E was found to be < or = 4. To explain the high preference of B. cepacia lipase for (R)-(+)-1, a precursor of its transition state analogue with a tetrahedral P-atom, (R(P),S(P))-O-(2R)-(1-phenoxybut-2-yl)methylphosphonic acid chloride was prepared and crystallized in complex with B. cepacia lipase. The X-ray structure of the complex was determined, allowing to compare the conformation of the inhibitor with results of molecular modelling.


Assuntos
Burkholderia cepacia/enzimologia , Lipase/química , Compostos Organofosforados/metabolismo , Catálise , Cristalografia por Raios X , Ligação de Hidrogênio , Lipase/antagonistas & inibidores , Lipase/metabolismo , Modelos Moleculares , Estereoisomerismo , Especificidade por Substrato
11.
J Immunol ; 165(12): 6738-42, 2000 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-11120792

RESUMO

Previous studies have documented that targeting foreign Ags to IgG FcgammaR leads to enhanced Ag-specific responses in vitro and in vivo. However, the ability to overcome immunologic nonresponsiveness by targeting poorly immunogenic Ags to FcgammaR has not been investigated. To address this question in a simple model, we immunized transgenic mice expressing human CD64 (FcgammaRI) and their nontransgenic littermates with Fab' derived from the murine anti-human CD64 mAb m22. The m22 Fab' served as both the targeting molecule and the Ag. We found that only CD64-expressing mice developed anti-Id titers to m22. Furthermore, chemically linked multimers of m22 Fab', which mediated efficient internalization of the human CD64, were significantly more potent than monomeric m22 F(ab')(2) at inducing anti-Id responses. In all cases, the humoral responses were specific for m22 Id and did not react with other murine IgG1 Fab' fragments. Chemical addition of a second murine Fab' (520C9 anti-human HER2/neu) to m22 Fab' multimers demonstrated that IgG1 and IgG2a anti-Id titers could be generated to 520C9 only in the CD64-expressing mice. These results show that targeting to CD64 can overcome immunological nonresponsiveness to a weak immunogen. Therefore, targeting to CD64 may be an effective method to enhance the activity of nonimmunogenic tumor vaccines.


Assuntos
Anticorpos Anti-Idiotípicos/biossíntese , Antígenos/imunologia , Camundongos Transgênicos/imunologia , Receptor ErbB-2/imunologia , Receptores de IgG/genética , Receptores de IgG/imunologia , Animais , Anticorpos Anti-Idiotípicos/metabolismo , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais/genética , Anticorpos Monoclonais/imunologia , Especificidade de Anticorpos/genética , Antígenos/administração & dosagem , Sítios de Ligação de Anticorpos/genética , Relação Dose-Resposta Imunológica , Feminino , Humanos , Fragmentos Fab das Imunoglobulinas/administração & dosagem , Fragmentos Fab das Imunoglobulinas/genética , Fragmentos Fab das Imunoglobulinas/imunologia , Imunoglobulina G/imunologia , Isotipos de Imunoglobulinas/biossíntese , Camundongos , Camundongos Endogâmicos , Modelos Imunológicos , Receptor ErbB-2/administração & dosagem , Receptores de IgG/metabolismo , Fatores de Tempo
12.
Hum Genet ; 107(3): 225-33, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11071383

RESUMO

Congenital amegakaryocytic thrombocytopenia (CAMT) without physical anomalies is a rare disease, presenting isolated thrombocytopenia and megakaryocytopenia in infancy, which can evolve into aplastic anemia and leukemia. Recently, two heterozygous truncating mutations of the thrombopoietin (TPO) receptor MPL, coded by the c-mpl gene, were identified in a 10-year-old Japanese patient with CAMT transmitted in an autosomal recessive manner. Here, we report for the first time two different MPL amino-acid substitutions in a 2-year-old Italian boy with CAMT and compound heterozygosis for two (c-mpl point mutations. C-to-T transitions were detected on exons 5 and 12 at the 769 and 1904 cDNA nucleotide positions, respectively. The mutation in exon 5 substitutes an arginine with a cysteine (R257C) in the extracellular domain, 11 amino acids distant from the WSXWS motif conserved in the cytokine-receptor superfamily. The mutation in exon 12 substitutes a proline with a leucine (P635L) in the last amino acid of the C-terminal intracellular domain, responsible for signal transduction. As in the Japanese family, the mutations were both transmitted from the parents. TPO plasma levels were highly increased in the patient. The patient's 7-year-old brother, who was a candidate donor for allografting, turned out to be an asymptomatic heterozygous carrier of P635L and showed defective megakaryocyte colony formation from bone-marrow progenitor cells. The present study provides important confirmation that CAMT can be associated with (c-mpl) mutations.


Assuntos
Megacariócitos , Proteínas de Neoplasias , Mutação Puntual , Proteínas Proto-Oncogênicas/genética , Receptores de Citocinas , Trombocitopenia/congênito , Sequência de Aminoácidos , Células da Medula Óssea , Pré-Escolar , Feminino , Heterozigoto , Humanos , Itália , Masculino , Dados de Sequência Molecular , Linhagem , Receptores de Trombopoetina , Homologia de Sequência de Aminoácidos
14.
J Immunol ; 164(11): 5746-52, 2000 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-10820252

RESUMO

Macrophages represent an important effector cell for Ab-mediated tumor therapy. Previous studies have documented that cytokines can influence Fc receptor (FcR) expression and function. In this study we examined the tumoricidal activities of the type I receptors for IgG (Fc gamma RI) and the IgA FcR (Fc alpha RI) on monocyte-derived macrophages (MDM) cultured in the presence of IFN-gamma, M-CSF, or GM-CSF. Bispecific Abs were used to target a Her2/neu breast carcinoma cell line, SKBR-3, to Fc alpha RI or Fc gamma RI on MDM. Although Fc alpha RI and Fc gamma RI share a common signaling pathway contingent on association with the gamma-chain (FcR gamma subunit), a marked difference in their efficiency in mediating tumoricidal functions was seen in response to specific cytokines. M-CSF- and GM-CSF-treated MDM mediated efficient phagocytosis of SKBR-3 cells by Fc alpha RI and Fc gamma RI; however, IFN-gamma-treated MDM phagocytosed tumor cells only with the Fc gamma RI-directed bispecific Abs. Similarly, IFN-gamma-cultured MDM lysed tumor cells more efficiently via Fc gamma RI then by Fc alpha RI as measured in Ab-dependent cellular cytotoxicity assays. Conversely, GM-CSF-treated MDM mediated more efficient lysis of tumor cells via Fc alpha RI than Fc gamma RI, while M-CSF-cultured MDM were relatively less efficient in mediating Ab-dependent cellular cytotoxicity through either receptor. With the exception of IFN-gamma-mediated enhancement of Fc gamma RI expression and Fc gamma RI gamma-chain complexes, the regulation of Fc gamma RI- or Fc alpha RI-mediated activity occurred without significant change in either receptor expression or total complexes with gamma subunit. These data suggest that the efficiency of Ab-mediated tumor therapy, which depends on FcR effector cell functions, may be modified by the use of specific cytokines.


Assuntos
Citotoxicidade Celular Dependente de Anticorpos/imunologia , Antígenos CD/fisiologia , Citocinas/farmacologia , Imunoglobulina A/metabolismo , Macrófagos/imunologia , Monócitos/imunologia , Receptores Fc/fisiologia , Receptores de IgG/fisiologia , Adjuvantes Imunológicos/farmacologia , Adulto , Anticorpos Biespecíficos/farmacologia , Diferenciação Celular/imunologia , Sobrevivência Celular/imunologia , Testes Imunológicos de Citotoxicidade/métodos , Citometria de Fluxo , Humanos , Macrófagos/citologia , Monócitos/citologia , Fagocitose/imunologia , Células Tumorais Cultivadas/imunologia
15.
Radiol Med ; 100(6): 465-9, 2000 Dec.
Artigo em Italiano | MEDLINE | ID: mdl-11307508

RESUMO

PURPOSE: Penetrating liver wounds are related to many causes and rank second after blunt abdominal and liver trauma. We will report the clinical and radiological findings of our personal series of patients with penetrating trauma, especially by firearms and stab and cut wounds. We will also try to define the diagnostic workup of these traumas, which is especially based on CT signs of liver damage and associated changes and which is of basic importance for following treatment, both surgical or conservative. MATERIAL AND METHODS: In the last seven years we retrospectively reviewed 31 cases of penetrating liver trauma. The patients were 19 men and 12 women, ranging in age 18 to 73 (mean 42), with penetrating liver injuries from firearms (16 patients) and stab (9 cases) wounds; 6 patients had injuries from different causes. Abdominal CT was carried out in emergency with the CT Angiography (CTA) technique in all patients. In the patients with suspected chest and abdomen involvement CT was performed from the mid-chest for accurate assessment of diaphragm and lung bases and to exclude associated pleuropulmonary damage. RESULTS: Penetrating liver wounds were caused by firearms in 70% of cases, by stabbing in 12% and, in the extant 18%, by other causes such as home accidents, road and work traumas, and liver biopsy. In our series, the liver was most frequently involved, especially by firearms wounds; in our 16 cases the most frequent injuries were hemorrhagic tears. We found bullets in the liver in 6 cases. In one case of home accident the patient wounded himself while slicing bread with a long knife, which cut into the anterior abdominal wall and tore the anterior liver capsule, as seen at CTA. DISCUSSION AND CONCLUSIONS: Penetrating wounds to liver and abdomen are less frequent than those to the chest. In the past decade the use of CT has changed the diagnostic and therapeutic approach to such injuries completely, decreasing the resort to explorative laparotomy and hepatorrhaphy. Indeed, CT provides a clear picture of the extent and severity of damage, which permits to choose a conservative treatment in case of intraparenchymal hematomas and lacerocontusive foci without hemoperitoneum, which can be followed-up with physical and CT examinations. Moreover, Helical CT could provide the early diagnosis of active bleeding in the peritoneum and of focal bleeding in the liver, thus permitting prompt hepatorrhaphy or targeted hepatectomy. A diaphragm injury suspected at CT should always prompt the surgeon to intervention, especially when hemothorax, lung base pneumothorax, large liver hematoma or tear of the liver dome are associated. Finally, subdiaphragmatic free gas indicates gut perforation associated with liver damage, in which case surgery is necessary too.


Assuntos
Fígado/lesões , Tomografia Computadorizada por Raios X , Ferimentos Penetrantes , Traumatismos Abdominais/diagnóstico por imagem , Adolescente , Adulto , Fatores Etários , Idoso , Feminino , Hepatectomia , Humanos , Fígado/diagnóstico por imagem , Fígado/cirurgia , Masculino , Pessoa de Meia-Idade , Fatores Sexuais , Ferimentos por Arma de Fogo/diagnóstico por imagem , Ferimentos Penetrantes/diagnóstico por imagem , Ferimentos Penetrantes/cirurgia , Ferimentos Perfurantes/diagnóstico por imagem
16.
Biol Chem ; 381(12): 1233-43, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11209758

RESUMO

Dipeptidyl peptidase (DPP III) was purified from rat and human erythrocytes using an identical procedure. Electrophoretic analyses revealed the same molecular size and pI for both enzymes. The molecular mass of the human enzyme, measured by matrix-assisted laser desorption/ionization MS, was 82500+/-60 Da. Its tryptic peptide mass profile was determined using the same technique, and the amino acid sequence of two internal peptides was obtained by tandem MS and Edman degradation. A search of databases revealed a high similarity between the human erythrocyte and rat liver DPP III: 21 matches out of 34 detected peptides were found, covering 40% of the total sequence. Matched peptides included the peptide harboring the characteristic HELLGH sequence motif, and a stretch of 19 identical amino acids, containing Glu, a putative ligand of active site zinc. Both enzymes preferred Arg-Arg-2-naphthylamide, and were activated by micromolar Co2+, differing in their pH optima and kcat/Km. Zn2+ ions, sulfhydryl reagents, and aminopeptidase inhibitors, especially probestin, inhibited the rat DPP III more potently. The two enzymes showed the highest affinity for angiotensin III (Ki < 1 microM) and a preference for ahydrophobic residue at the P1' site. However, significant differences in the binding constants for several peptides indicated non-identity in the active site topography of human and rat erythrocyte DPP III.


Assuntos
Dipeptidil Peptidases e Tripeptidil Peptidases , Motivos de Aminoácidos , Sequência de Aminoácidos , Animais , Dipeptidil Peptidases e Tripeptidil Peptidases/sangue , Dipeptidil Peptidases e Tripeptidil Peptidases/química , Dipeptidil Peptidases e Tripeptidil Peptidases/isolamento & purificação , Eritrócitos/enzimologia , Humanos , Cinética , Espectrometria de Massas , Dados de Sequência Molecular , Peso Molecular , Mapeamento de Peptídeos , Ratos , Análise de Sequência de Proteína , Especificidade por Substrato
17.
Arch Microbiol ; 171(6): 397-404, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10369895

RESUMO

Lapstatin, a low-molecular-weight aminopeptidase inhibitor, was purified to homogeneity from Streptomyces rimosus culture filtrates. The purification procedure included extraction with methanol, followed by chromatography on Dowex 50WX4, AG50WX4, and HPLC RP C18 columns. By amino acid analysis, mass spectrometry, and NMR spectroscopy, the structure of lapstatin was shown to be 3-amino-2-hydroxy-4-methylpentanoylvaline. Lapstatin inhibited the extracellular leucine aminopeptidases from Streptomyces rimosus, Streptomyces griseus, and Aeromonas proteolytica with an IC50 in the range of 0.3-2.4 microM. IC50 values for other enzymes tested were at least tenfold higher. Leucine aminopeptidase from Streptomyces griseus was inhibited in a competitive manner, with an inhibition constant of 5 x 10(-7) M. Lapstatin is the first low-molecular-weight compound isolated from streptomycetes shown to inhibit an autogenous aminopeptidase.


Assuntos
Proteínas de Bactérias/farmacologia , Inibidores Enzimáticos/farmacologia , Leucil Aminopeptidase/antagonistas & inibidores , Streptomyces/metabolismo , Valina/análogos & derivados , Proteínas de Bactérias/química , Proteínas de Bactérias/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Inibidores Enzimáticos/química , Inibidores Enzimáticos/isolamento & purificação , Leucil Aminopeptidase/metabolismo , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Streptomyces/enzimologia , Streptomyces/crescimento & desenvolvimento , Valina/química , Valina/isolamento & purificação , Valina/metabolismo , Valina/farmacologia
19.
Exp Hematol ; 27(1): 9-18, 1999 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9923439

RESUMO

The hematopoietic defect of Diamond-Blackfan anemia (DBA) results in selective failure of erythropoiesis. Thus far, it is not known whether this defect originates from an intrinsic impediment of hematopoietic progenitors to move forward along the erythroid pathway or to the impaired capacity of the bone marrow (BM) microenvironment to support proliferation and differentiation of hematopoietic cells. Reduced longevity of long-term bone marrow cultures, the most physiologic in vitro system to study the interactions of hematopoietic progenitors and hematopoietic microenvironment, is consistent with a defect of an early hematopoietic progenitor in DBA. However, stromal adherent layers from DBA patients generated in a long-term culture system, the in vitro counterpart of BM microenvironment, did not show evidence of any morphologic, phenotypic, or functional abnormality. Our major finding was an impaired capacity of enriched CD34+ BM cell fraction from DBA patients, cultured in the presence of normal BM stromal cells, to proliferate and differentiate along the erythroid pathway. A similar impairment was observed in some DBA patients along the granulomacrophage pathway. Our result points to an intrinsic defect of a hematopoietic progenitor with bilineage potential that is earlier than previously suspected as a relevant pathogenetic mechanism of the disease. The finding of impaired granulopoiesis in some DBA patients underlines the heterogeneity of this rare disorder.


Assuntos
Células da Medula Óssea/patologia , Anemia de Fanconi/patologia , Granulócitos/patologia , Células-Tronco Hematopoéticas/patologia , Macrófagos/patologia , Adolescente , Adulto , Antígenos CD34/análise , Células da Medula Óssea/imunologia , Células da Medula Óssea/fisiologia , Diferenciação Celular , Divisão Celular , Sobrevivência Celular , Células Cultivadas , Criança , Pré-Escolar , Meios de Cultivo Condicionados/farmacologia , Citocinas/genética , Células Precursoras Eritroides/efeitos dos fármacos , Células Precursoras Eritroides/metabolismo , Células Precursoras Eritroides/patologia , Feminino , Hematopoese/fisiologia , Células-Tronco Hematopoéticas/efeitos dos fármacos , Células-Tronco Hematopoéticas/metabolismo , Humanos , Imunofenotipagem , Lactente , Masculino , RNA Mensageiro/biossíntese , Células Estromais/fisiologia , Fatores de Tempo
20.
Minerva Chir ; 53(9): 735-7, 1998 Sep.
Artigo em Italiano | MEDLINE | ID: mdl-9866941

RESUMO

A rare case of bilateral spigelian hernia is presented and the anatomy and clinical problems related to this disease are discussed. The role of TC scan in the diagnosis of cases with difficult clinical evaluations is stressed.


Assuntos
Hérnia Ventral/diagnóstico , Músculos Abdominais/diagnóstico por imagem , Dor Abdominal/diagnóstico , Doença Crônica , Feminino , Hérnia Ventral/cirurgia , Humanos , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X , Ultrassonografia
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