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1.
J Endocrinol Invest ; 47(2): 455-468, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37480475

RESUMO

PURPOSE: Nearly, 40% of the causes of male infertility remain idiopathic. The only suggested treatment in idiopathic oligo- and/or asthenozoospermia in normogonadotropic patients is the FSH. In the current clinical practice, efficacy is exclusively assessable through semen analysis after 3 months of treatment. No molecular markers of treatment efficacy are appliable in clinical practice. The aim of the present work is to evaluate the combination of extracellular signal regulated kinase (ERK) 1 and 2 and prolactin inducible peptide (PIP) as potential markers of idiopathic infertility and FSH treatment efficacy. METHODS: Western blot and confocal microscopy were performed to analyze the modulation of PIP and ERK1/2 in idiopathic infertile patients (IIP) sperm cells. Taking advantage of mass spectrometry analysis, we identified these proteins unequivocally in sperm cells. RESULTS:  We demonstrated a significant decrease of both PIP protein and of ERK1/2 levels in spermatozoa obtained from IIP in comparison to healthy fertile patients (HFP). Conversely, we reported a significant increase of these markers comparing infertile patients before and after 3 months of FSH treatment. Importantly, this correlated with an increase in total number of sperm and sperm motility after FSH treatment. Finally, we identified of PIP and ERK2 proteins in sperm samples by proteomic analysis. CONCLUSIONS: The combined evaluation of ERK1/2 and PIP proteins might represent a useful molecular marker to tailor FSH treatment in the management of male normogonadotropic idiopathic infertility.


Assuntos
Infertilidade Masculina , Prolactina , Masculino , Humanos , MAP Quinases Reguladas por Sinal Extracelular , Proteômica , Sêmen , Motilidade dos Espermatozoides , Espermatozoides , Infertilidade Masculina/tratamento farmacológico , Resultado do Tratamento , Hormônio Foliculoestimulante/uso terapêutico
2.
Hum Genet ; 140(7): 1077-1096, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33944995

RESUMO

The Okur-Chung neurodevelopmental syndrome, or OCNDS, is a newly discovered rare neurodevelopmental disorder. It is characterized by developmental delay, intellectual disability, behavioral problems (hyperactivity, repetitive movements and social interaction deficits), hypotonia, epilepsy and language/verbalization deficits. OCNDS is linked to de novo mutations in CSNK2A1, that lead to missense or deletion/truncating variants in the encoded protein, the protein kinase CK2α. Eighteen different missense CK2α mutations have been identified to date; however, no biochemical or cell biological studies have yet been performed to clarify the functional impact of such mutations. Here, we show that 15 different missense CK2α mutations lead to varying degrees of loss of kinase activity as recombinant purified proteins and when mutants are ectopically expressed in mammalian cells. We further detect changes in the phosphoproteome of three patient-derived fibroblast lines and show that the subcellular localization of CK2α is altered for some of the OCNDS-linked variants and in patient-derived fibroblasts. Our data argue that reduced kinase activity and abnormal localization of CK2α may underlie the OCNDS phenotype.


Assuntos
Transtornos do Neurodesenvolvimento/enzimologia , Transtornos do Neurodesenvolvimento/genética , Animais , Células COS , Caseína Quinase II/química , Caseína Quinase II/genética , Caseína Quinase II/metabolismo , Linhagem Celular , Chlorocebus aethiops , Fibroblastos/enzimologia , Humanos , Espectrometria de Massas , Camundongos , Camundongos Knockout , Modelos Moleculares , Mutação de Sentido Incorreto
3.
Mol Biol (Mosk) ; 54(4): 688-698, 2020.
Artigo em Russo | MEDLINE | ID: mdl-32840490

RESUMO

A majority of BRCA1/2 (BRCA) pathogenic variants (PVs) are single nucleotide substitutions or small insertions/deletions. Copy number variations (CNVs), also known as large genomic rearrangements (LGRs), have been identified in BRCA genes. LGRs detection is a mandatory analysis in hereditary breast and ovarian cancer families, if no predisposing PVs are found by sequencing. Next generation sequencing (NGS) may be used to detect structural variation, since quantitative analysis of sequencing reads, when coupled with appropriate bioinformatics tools, is capable of estimating and predicting germline LGRs (gLGRs). However, applying this approach to tumor tissue is challenging, and the pipelines for determination of CNV are yet to be optimized. The aim of this study was to validate the Next Generation Tumor Sequencing (NGTS) technology to detect various gLGRs of BRCA1 locus in surgical tumor tissue samples. In this study, seven different BRCA1 gLGRs, previously found in high-grade serous ovarian cancers (HGSOC) patients, were detected in tumor samples collected from the patients at a time of HGSOC surgery. This study demonstrated that NGS can accurately detect BRCA1 gLGRs in primary tumors, suggesting that gLGR evaluation in BRCA1 locus should be performed in cases when the screening for BRCA alterations starts from tumor instead of blood. NGS sequencing of tumor samples may become the preferred method to detect both somatic and germline gLGRs in BRCA-encoding loci.


Assuntos
Proteína BRCA1/genética , Neoplasias da Mama/genética , Genes BRCA1 , Sequenciamento de Nucleotídeos em Larga Escala , Neoplasias Ovarianas/genética , Variações do Número de Cópias de DNA/genética , Feminino , Células Germinativas/metabolismo , Mutação em Linhagem Germinativa , Humanos
4.
Microbiol Spectr ; : e0438522, 2023 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-36975835

RESUMO

Candida auris is a multidrug-resistant fungus known to be a global public health problem. The skin-based transmission, together with the marked resistance to drugs, resulted in its rapid spread to all continents. The aim of this study was to identify an essential oil (EO) active in the fight against C. auris. A total of 15 EOs were tested against 10 clinical strains of C. auris. Cinnamomum zeylanicum EO (CZ-EO) was the most effective (MIC90 and MFC90 equal to 0.06% vol/vol). Three fractions obtained from CZ-EO, and the cinnamaldehyde (CIN), the major chemical compound, were tested to identify the principal compound effectives against C. auris. All CIN-containing samples showed anti-fungal activity. To study the synergy with fluconazole, CZ-EO, its active fraction (FR2), and CIN were tested in checkerboard tests. Results show that CZ-EO and FR2, but not CIN, synergize with fluconazole. Furthermore, only the copresence of CZ-EO or FR2 synergize with fluconazole at therapeutic concentrations of the drug (0.45 ± 0.32 µg/mL and 0.64 ± 0.67 µg/mL, respectively), while CIN only shows additive activity. In vivo studies conducted on Galleria mellonella larvae show the absence of toxicity of CZ-EO up to concentrations of 16% vol/vol, and the ability of CZ-EO to reactivate the efficacy of fluconazole when formulated at synergic concentrations. Finally, biochemical tests were made to study the mechanism of action of CZ-EO. These studies show that in the presence of both fluconazole and CZ-EO, the activity of fungal ATPases decreases and, at the same time, the amount of intracellular drug increases. IMPORTANCE This study highlights how small doses of CZ-EO are able to inhibit the secretion of fluconazole and promote its accumulation in the fungal cell. In this manner, the drug is able to exert its pharmacological effects bypassing the resistance of the yeast. If further studies will confirm this synergy, it will be possible to develop new therapeutic formulations active in the fight against C. auris resistances.

5.
Clin Biochem ; 66: 103-105, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30738031

RESUMO

We report a case of a heterophile antibodies interference in a new high-sensitivity troponin commercial immunoassay (cTNIH Siemens), observed in a patient with possible acute coronary syndrome (ACS). The analytical interference was investigated with standard laboratories procedures. The false positive result was found with different troponin methods and kits. We also investigated the protein sequence of cTnl and no sequence variants were detected. The discordance between clinical pictures and high concentration of cTnl, together with the collaboration between clinicians and laboratory staff avoided possible erroneous diagnosis and further invasive investigations to the patient.


Assuntos
Dor no Peito/sangue , Troponina I/sangue , Animais , Anticorpos Heterófilos/imunologia , Anticorpos Monoclonais/imunologia , Bovinos , Reações Falso-Positivas , Cabras , Humanos , Imunoensaio/métodos , Masculino , Camundongos , Pessoa de Meia-Idade , Ovinos , Troponina I/imunologia
7.
Eur Rev Med Pharmacol Sci ; 23(7): 2978-2985, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31002168

RESUMO

OBJECTIVE: Biochemical markers are commonly used in medicine to guide diagnostic investigation or therapy duration and/or monitor treatment efficacy. Due to the emergence and spread of antimicrobial resistance, markers able to prompt a more rational use of antimicrobial therapy are regarded with the greatest attention. Procalcitonin (PCT) certainly stands out among others, yet its role must be better established especially outside of the critical care area. Data about PCT utilization in non-critical patients, optimal negativity cut-offs as well as a protocol for measurement timing are all lacking. MATERIALS AND METHODS: To address these issues, a focus group was set up to propose and endorse shared statements regarding the most beneficial use of PCT in real life as infection marker for non-critical patients, based on the authors' experience and a review of recent literature. RESULTS: A group of nine experts in the fields of Infectious Diseases, Internal Medicine, Microbiology, Clinical Chemistry, Surgery and Medical Economics participated in the discussion of nine pre-specified statements. CONCLUSIONS: The potential role for PCT in differentiating infectious and non-infectious clinical syndromes and guiding antimicrobial therapy discontinuation was acknowledged. Moreover, a shared measurement protocol and desirable cut-offs for the non-critical area were proposed. Finally, observations were made about a reasonable selection of the patient population to be tested.


Assuntos
Antibacterianos/uso terapêutico , Gestão de Antimicrobianos/normas , Farmacorresistência Bacteriana/efeitos dos fármacos , Prova Pericial/normas , Unidades de Terapia Intensiva/normas , Pró-Calcitonina/sangue , Antibacterianos/farmacologia , Gestão de Antimicrobianos/métodos , Infecções Bacterianas/sangue , Infecções Bacterianas/tratamento farmacológico , Biomarcadores/sangue , Farmacorresistência Bacteriana/fisiologia , Prova Pericial/métodos , Humanos , Unidades de Terapia Intensiva/tendências
8.
Equine Vet J ; 50(5): 594-601, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29393535

RESUMO

BACKGROUND: There are limited findings from low-powered studies based on few number of subjects with equine asthma. Furthermore, no studies have been performed to assess a meaningful clinically detectable impact of corticosteroids in equine asthma. OBJECTIVES: To assess and compare the clinical effect of inhaled and systemic corticosteroids in equine asthma and identify a quantitative clinical score suitable to assess the Minimal Important Difference (MID), expressed as the Minimally Clinically Detectable Difference (MCDD). STUDY DESIGN: Pair-wise and network meta-analysis. METHODS: Literature searches for studies on corticosteroid therapy in equine asthma were performed. The risk of publication bias was assessed by Funnel plots and Egger's test. The effect on changes in clinical scores vs. control was analysed via random-effects models and Bayesian networks. RESULTS: Corticosteroids significantly improved the clinical condition (Standardised Mean Difference: -1.52, 95% CrI -2.07 to -0.98; P<0.001 vs. control). No difference was detected between inhaled and systemic corticosteroids with regard to the changes in clinical scores (Relative Effect: 0.08, 95% CrI -1.45 to 1.32; P = 0.8). An Improved clinically Detectable Equine Asthma Scoring System (IDEASS) indicated that corticosteroids improved the clinical condition of asthmatic horses by 30% compared with controls (IDEASS value: -2.36, 95% CI -3.39 to -1.33; P<0.001). A one-point change in IDEASS represented the MCDD in equine asthma. MAIN LIMITATIONS: Moderate quality of evidence for systemic corticosteroids. CONCLUSIONS: Inhaled corticosteroids are effective in improving the clinical condition of horses with equine asthma and prevent exacerbations. Systemic corticosteroids should be used only in selected cases with symptomatic airway hyperresponsiveness during exacerbation. IDEASS requires further validation but may represent a suitable approach to rank the level of asthma severity and assess the clinical effect of pharmacotherapy in horses with equine asthma.


Assuntos
Corticosteroides/uso terapêutico , Asma/veterinária , Doenças dos Cavalos/tratamento farmacológico , Corticosteroides/administração & dosagem , Animais , Asma/tratamento farmacológico , Vias de Administração de Medicamentos/veterinária , Cavalos
9.
Equine Vet J ; 49(6): 710-717, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28295526

RESUMO

BACKGROUND: Equine asthma is a disease characterised by reversible airflow obstruction, bronchial hyper-responsiveness and airway inflammation following exposure of susceptible horses to specific airborne agents. Although clinical remission can be achieved in a low-airborne dust environment, repeated exacerbations may lead to irreversible airway remodelling. The available data on the pharmacotherapy of equine asthma result from several small studies, and no head-to-head clinical trials have been conducted among the available medications. OBJECTIVES: To assess the impact of the pharmacological interventions in equine asthma and compare the effect of different classes of drugs on lung function. STUDY DESIGN: Pair-wise and network meta-analysis. METHODS: Literature searches for clinical trials on the pharmacotherapy of equine asthma were performed. The risk of publication bias was assessed by funnel plots and Egger's test. Changes in maximum transpulmonary or pleural pressure, pulmonary resistance and dynamic lung compliance vs. control were analysed via random-effects models and Bayesian networks. RESULTS: The results obtained from 319 equine asthma-affected horses were extracted from 32 studies. Bronchodilators, corticosteroids and chromones improved maximum transpulmonary or pleural pressure (range: -8.0 to -21.4 cmH2 O; P<0.001). Bronchodilators, corticosteroids and furosemide reduced pulmonary resistance (range: -1.2 to -1.9 cmH2 O/L/s; P<0.001), and weakly increased dynamic lung compliance. Inhaled ß2 -adrenoreceptor (ß2 -AR) agonists and inhaled corticosteroids had the highest probability of being the best therapies. Long-term treatments were more effective than short-term treatments. MAIN LIMITATIONS: Weak publication bias was detected. CONCLUSIONS: This study demonstrates that long-term treatments with inhaled corticosteroids and long-acting ß2 -AR agonists may represent the first choice for treating equine asthma. Further high quality clinical trials are needed to clarify whether inhaled bronchodilators should be preferred to inhaled corticosteroids or vice versa, and to investigate the potential superiority of combination therapy in equine asthma.


Assuntos
Corticosteroides/uso terapêutico , Asma/veterinária , Broncodilatadores/uso terapêutico , Doenças dos Cavalos/tratamento farmacológico , Animais , Asma/tratamento farmacológico , Cavalos
10.
Transl Psychiatry ; 6(9): e904, 2016 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-27676445

RESUMO

Chronic fatigue syndrome (CFS) is a debilitating and complex disorder characterized by unexplained fatigue not improved by rest. An area of investigation is the likely connection of CFS with defective mitochondrial function. In a previous work, we investigated the proteomic salivary profile in a couple of monozygotic twins discordant for CFS. Following this work, we analyzed mitochondrial proteins in the same couple of twins. Nano-liquid chromatography electrospray ionization mass spectrometry (nano-LC-MS) was used to study the mitochondria extracted from platelets of the twins. Subsequently, we selected three proteins that were validated using western blot analysis in a big cohort of subjects (n=45 CFS; n=45 healthy), using whole saliva (WS). The selected proteins were as follows: aconitate hydratase (ACON), ATP synthase subunit beta (ATPB) and malate dehydrogenase (MDHM). Results for ATPB and ACON confirmed their upregulation in CFS. However, the MDHM alteration was not confirmed. Thereafter, seeing the great variability of clinical features of CFS patients, we decided to analyze the expression of our proteins after splitting patients according to clinical parameters. For each marker, the values were actually higher in the group of patients who had clinical features similar to the ill twin. In conclusion, these results suggest that our potential markers could be one of the criteria to be taken into account for helping in diagnosis. Furthermore, the identification of biomarkers present in particular subgroups of CFS patients may help in shedding light upon the complex entity of CFS. Moreover, it could help in developing tailored treatments.

11.
Cell Death Dis ; 7: e2090, 2016 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-26866271

RESUMO

Members of the bcl-2 protein family share regions of sequence similarity, the bcl-2 homology (BH) domains. Bcl-2, the most studied member of this family, has four BH domains, BH1-4, and has a critical role in resistance to antineoplastic drugs by regulating the mitochondrial apoptotic pathway. Moreover, it is also involved in other relevant cellular processes such as tumor progression, angiogenesis and autophagy. Deciphering the network of bcl-2-interacting factors should provide a critical advance in understanding the different functions of bcl-2. Here, we characterized bcl-2 interactome by mass spectrometry in human lung adenocarcinoma cells. In silico functional analysis associated most part of the identified proteins to mitochondrial functions. Among them we identified SRA stem-loop interacting RNA-binding protein, SLIRP, a mitochondrial protein with a relevant role in regulating mitochondrial messenger RNA (mRNA) homeostasis. We validated bcl-2/SLIRP interaction by immunoprecipitation and immunofluorescence experiments in cancer cell lines from different histotypes. We showed that, although SLIRP is not involved in mediating bcl-2 ability to protect from apoptosis and oxidative damage, bcl-2 binds and stabilizes SLIRP protein and regulates mitochondrial mRNA levels. Moreover, we demonstrated that the BH4 domain of bcl-2 has a role in maintaining this binding.


Assuntos
Espectrometria de Massas/métodos , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteínas de Ligação a RNA/metabolismo , Apoptose/fisiologia , Humanos , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/isolamento & purificação , Espécies Reativas de Oxigênio/metabolismo
12.
Oncogene ; 35(2): 228-40, 2016 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-25961923

RESUMO

The p53 inhibitor, MDM4 (MDMX) is a cytoplasmic protein with p53-activating function under DNA damage conditions. Particularly, MDM4 promotes phosphorylation of p53 at Ser46, a modification that precedes different p53 activities. We investigated the mechanism by which MDM4 promotes this p53 modification and its consequences in untransformed mammary epithelial cells and tissues. In response to severe DNA damage, MDM4 stimulates p53Ser46(P) by binding and stabilizing serine-threonine kinase HIPK2. Under these conditions, the p53-inhibitory complex, MDM4/MDM2, dissociates and this allows MDM4 to promote p53/HIPK2 functional interaction. Comparative proteomic analysis of DNA damage-treated cells versus -untreated cells evidenced a diffuse downregulation of proteins with anti-apoptotic activity, some of which were targets of p53Ser46(P)/HIPK2 repressive activity. Importantly, MDM4 depletion abolishes the downregulation of these proteins indicating the requirement of MDM4 to promote p53-mediated transcriptional repression. Consistently, MDM4-mediated HIPK2/p53 activation precedes HIPK2/p53 nuclear translocation and activity. Noteworthy, repression of these proteins was evident also in mammary glands of mice subjected to γ-irradiation and was significantly enhanced in transgenic mice overexpressing MDM4. This study evidences the flexibility of MDM2/MDM4 heterodimer, which allows the development of a positive activity of cytoplasmic MDM4 towards p53-mediated transcriptional function. Noteworthy, this activity uncovers coordinated repression of molecules with shared anti-apoptotic function which precedes active cell apoptosis and that are frequently overexpressed and/or markers of tumour phenotype in human cancer.


Assuntos
Apoptose/fisiologia , Proteínas de Transporte/metabolismo , Dano ao DNA/fisiologia , Proteínas Nucleares/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Animais , Sequência de Bases , Proteínas de Transporte/genética , Proteínas de Ciclo Celular , Citoplasma/metabolismo , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Feminino , Fibroblastos/metabolismo , Fibroblastos/patologia , Células HCT116 , Humanos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Dados de Sequência Molecular , Proteínas Nucleares/genética , Proteínas Serina-Treonina Quinases/genética , Proteínas Proto-Oncogênicas/genética , Serina/metabolismo , Proteína Supressora de Tumor p53/genética , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo
13.
Biochim Biophys Acta ; 1459(2-3): 266-73, 2000 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-11004439

RESUMO

Nitric oxide reductases (NORs) that are found in bacteria belong to the large enzyme family which includes cytochrome oxidases. Two types of bacterial NORs have been characterised. One is a cytochrome bc-type complex (cNOR) that receives electrons from soluble redox protein donors, whereas the other type (qNOR) lacks the cytochrome c component and uses quinol as the electron donor. The latter enzyme is present in several pathogens that are not denitrifiers. We summarise the current knowledge on bacterial NORs, and discuss the evolutionary relationship between them and cytochrome oxidases in this review.


Assuntos
Bactérias/genética , Oxirredutases/genética , Sequência de Aminoácidos , Bactérias/classificação , Bactérias/enzimologia , Sítios de Ligação , Evolução Molecular , Dados de Sequência Molecular , Oxirredutases/química , Alinhamento de Sequência
14.
FEBS Lett ; 508(1): 29-35, 2001 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-11707262

RESUMO

Cytochrome cbb(3) is a cytochrome c-oxidising isoenzyme that belongs to the superfamily of respiratory haem/copper oxidases. We have developed a purification method yielding large amounts of pure cbb(3) complex from the soil bacterium Pseudomonas stutzeri. This cytochrome cbb(3) complex consists of three subunits (ccoNOP) in a 1:1:1 stoichiometry and contains two b-type and three c-type haems. The protein complex behaves as a monomer with an overall molecular weight of 114.0+/-8.9 kDa and a s(0)(20,w) value of 8.9+/-0.3 S as determined by analytical ultracentrifugation. Crystals diffracting to 5.0 A resolution have been grown by the vapour diffusion sitting drop method to an average size of 0.1 x 0.1 x 0.3 mm. This is the first crystallisation report of a (cbb(3))-type oxidase.


Assuntos
Complexo IV da Cadeia de Transporte de Elétrons/química , Pseudomonas/enzimologia , Sequência de Aminoácidos , Fracionamento Celular , Cristalização , Detergentes/química , Complexo IV da Cadeia de Transporte de Elétrons/isolamento & purificação , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Complexo IV da Cadeia de Transporte de Elétrons/ultraestrutura , Dados de Sequência Molecular , Peso Molecular , Subunidades Proteicas , Pseudomonas/química , Solubilidade , Ultracentrifugação , Difração de Raios X
15.
Arch Virol Suppl ; 4: 304-5, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1450709

RESUMO

Twenty-four patients with HCV and NonBNonC chronic hepatitis--4 with HIV coinfection--were treated with r-IFN alpha for at least six months. In this period 62.5% of patients show a normalization of ALT but not a sustained remission. Non-responders have histologically more severe and long-lasting chronic hepatitis.


Assuntos
Hepatite C/terapia , Hepatite Crônica/terapia , Hepatite Viral Humana/terapia , Interferon-alfa/uso terapêutico , Adulto , Idoso , Alanina Transaminase/sangue , Feminino , Humanos , Interferon alfa-2 , Masculino , Pessoa de Meia-Idade , Proteínas Recombinantes , Indução de Remissão
16.
Peptides ; 18(5): 741-8, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9213370

RESUMO

The interindividual variability of the hydrolysis of leucine enkephalin, and of the formation of its hydrolysis by-products has been studied in human plasma. In agreement with known data, the data obtained indicate that Leu-enkephalin is degraded by several enzymes, belonging to three classes: aminopeptidases, dipeptidylaminopeptidases, and dipeptidylcarboxypeptidases. The relative ratio of the substrate degraded by each enzyme class-as well as the expression of the single enzyme species within each class-appears to be individually determined. Interindividual variability observed seems controlled by two main factors: the pattern of enkephalin-degrading enzymes and, more notably, the low molecular weight plasma inhibitors. Both these factors appear to be partially specific of each donor. Possibly because of the composition of these factors, the hydrolysis pattern of the substrate is characteristic of each donor, and constant in blood obtained from successive drawings, at least within a relatively short period of time.


Assuntos
Encefalinas/sangue , Plasma/enzimologia , Adulto , Aminopeptidases/sangue , Fracionamento Químico , Interpretação Estatística de Dados , Dipeptidil Peptidases e Tripeptidil Peptidases/sangue , Endopeptidases/sangue , Feminino , Humanos , Hidrólise , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Peso Molecular , Inibidores de Proteases/sangue , Inibidores de Proteases/isolamento & purificação , Reprodutibilidade dos Testes , Especificidade por Substrato
17.
Peptides ; 17(3): 451-9, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8735972

RESUMO

Hydrolysis and inhibition of hydrolysis of leucine enkephalin in Oryctolagus plasma were studied by kinetics and chromatographic techniques. By data obtained, in this species, enkephalins are degraded by the same enzymes active in other mammals: aminopeptidases, dipeptidylaminopeptidases, and dipeptidylcarboxypeptidases. At variance with data obtained in other species, where enkephalins are hydrolyzed mostly by aminopeptidases, in Oryctolagus Leu-enkephalin hydrolysis is mainly due to dipeptidylcarboxypeptidases, whereas aminopeptidases contribution is the minimum of all three enzyme groups. Comparative analyses performed in the presence and in the absence of plasma inhibitors indicate that the ability of these substances to reduce substratum hydrolysis is very limited. On the contrary, the specific hydrolysis pattern evidenced appears to originate primarily from selective inhibition of the three groups of enzymes. Results obtained appear consistent with a role of plasma inhibitors in tuning hydrolysis to specific substrata, without appreciably modifying the amount of the substratum degraded.


Assuntos
Endopeptidases/sangue , Encefalina Leucina/metabolismo , Inibidores de Proteases/sangue , Aminopeptidases/sangue , Aminopeptidases/isolamento & purificação , Animais , Carboxipeptidases/sangue , Carboxipeptidases/isolamento & purificação , Endopeptidases/classificação , Endopeptidases/isolamento & purificação , Hidrólise , Inibidores de Proteases/isolamento & purificação , Coelhos , Especificidade da Espécie
18.
Peptides ; 15(7): 1213-22, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-7854972

RESUMO

Hydrolysis of Leu-enkephalin and association to cells of the peptide-radioactive label have been studied on the K562(S) erythroleukemic cell subline. Data obtained indicate that in the presence of these cells, Leu-enkephalin is hydrolyzed, that the peptide's radioactive label is partially associated to cells, and that these phenomena are related. Hydrolysis and association are inversely modified by the cells' differentiation: hydrolysis is increased and association is decreased in differentiated compared with nondifferentiated cells. Moreover, the ratio of hydrolysis by-products is dissimilar between differentiated and nondifferentiated cells as a result of a significant modification of the soluble enzymes' release. The alterations induced by differentiation on all parameters investigated seem to indicate significant changes in the membrane structures responsible for the mechanisms controlling these phenomena.


Assuntos
Encefalina Leucina/metabolismo , Leucemia Eritroblástica Aguda/metabolismo , Sequência de Aminoácidos , Diferenciação Celular , Dipeptídeos/química , Dipeptídeos/metabolismo , Endopeptidases/isolamento & purificação , Endopeptidases/metabolismo , Humanos , Hidrólise , Cinética , Leucemia Eritroblástica Aguda/patologia , Dados de Sequência Molecular , Oligopeptídeos/química , Oligopeptídeos/metabolismo , Inibidores de Proteases/farmacologia , Células Tumorais Cultivadas/efeitos dos fármacos , Células Tumorais Cultivadas/metabolismo , Células Tumorais Cultivadas/patologia , Tirosina/metabolismo
19.
Peptides ; 19(7): 1155-63, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9786164

RESUMO

Possible age-induced variations of the hydrolysis of leucine enkephalin in the presence of plasma enzymes were studied by kinetic and chromatographic techniques in a group of elderly individuals. Results obtained indicate that in elderly individuals the activity of enkephalin-degrading plasma enzymes is greater than in the controls; ANOVA analysis of these data indicates that the dependency of the variation of hydrolysis upon the two age groups is statistically significant. Increased substrate hydrolysis, and a modified hydrolysis pattern, appear to be associated with increased activity of the enzymes involved, and with different distribution of the individual enzymes within each class, as well as with severely reduced activity of the low molecular weight plasma inhibitors. The combination of these factors defines a characteristic hydrolysis pattern for the elderly individuals, different from that found in the controls.


Assuntos
Envelhecimento/sangue , Encefalina Leucina/sangue , Peptídeo Hidrolases/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , Aminopeptidases/antagonistas & inibidores , Aminopeptidases/sangue , Análise de Variância , Cromatografia em Gel , Cromatografia em Camada Fina , Feminino , Glicina/sangue , Humanos , Hidrólise , Cinética , Masculino , Peso Molecular , Inibidores de Proteases/sangue , Tirosina/sangue
20.
Minerva Med ; 84(11): 637-40, 1993 Nov.
Artigo em Italiano | MEDLINE | ID: mdl-8015693

RESUMO

Lymphoid hypophysitis is a rare disease (fewer than 30 cases) which is associated with lymphocytic infiltration of the pituitary gland with complete or partial hypopituitarism, pituitary mass, and occurrence exclusively in women, often during pregnancy or in the postpartum period. The majority of the women had autoimmune endocrine and not endocrine disorders and in some cases antipituitary antibodies were present. For these reasons an autoimmune cause has been suggested. We report a patient in menopause with chronic thyroiditis and anti nuclear, anti smooth muscle and anti mitochondrial autoantibodies who developed a panhypopituitarism with an empty sella. This case is the third observation of a possible autoimmune atrophy of the pituitary.


Assuntos
Doenças Autoimunes , Hipófise/imunologia , Idoso , Feminino , Humanos , Inflamação , Hipófise/patologia
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