Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 95
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
Mol Ecol ; 25(10): 2258-72, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26994404

RESUMO

Microbial species richness and assemblages across ultramafic ecosystems were investigated to assess the relationship between their distributional patterns and environmental traits. The structure of microorganism communities in the Koniambo massif, New Caledonia, was investigated using a metagenetic approach correlated with edaphic and floristic factors. Vegetation cover and soil properties significantly shaped the large phylogenetic distribution of operational taxonomic unit within microbial populations, with a mean per habitat of 3.477 (±317) for bacteria and 712 (±43) for fungi. Using variance partitioning, we showed that the effect of aboveground vegetation was the most significant descriptor for both bacterial and fungal communities. The floristic significant predictors explained 43% of the variation for both the bacterial and fungal community structures, while the edaphic significant predictors explained only 32% and 31% of these variations, respectively. These results confirm the previous hypothesis that the distribution of microorganisms was more structured by the vegetation cover rather than the edaphic characteristics and that microbial diversity is not limited in ultramafic ecosystems.


Assuntos
Bactérias/classificação , Ecossistema , Fungos/classificação , Microbiota , Microbiologia do Solo , Biodiversidade , DNA Bacteriano/genética , DNA Fúngico/genética , Florestas , Nova Caledônia , Filogenia , Plantas , Análise de Sequência de DNA
2.
Br J Cancer ; 108(12): 2495-504, 2013 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-23736031

RESUMO

BACKGROUND: A 28 amino-acid (aa) cell-penetrating peptide (p28) derived from azurin, a redox protein secreted from the opportunistic pathogen Pseudomonas aeruginosa, produces a post-translational increase in p53 in cancer cells by inhibiting its ubiquitination. METHODS: In silico computational simulations were used to predict motifs within the p53 DNA-binding domain (DBD) as potential sites for p28 binding. In vitro direct and competitive pull-down studies as well as western blot and RT-PCR analyses were used to validate predictions. RESULTS: The L1 loop (aa 112-124), a region within the S7-S8 loop (aa 214-236) and T140, P142, Q144, W146, R282 and L289 of the p53DBD were identified as potential sites for p28 binding. p28 decreased the level of the E3 ligase COP1 >80%, in p53wt and p53mut cells with no decrease in COP1 in p53dom/neg or p53null cells. Brief increases in the expression of the E3 ligases, TOPORS, Pirh2 and HDM2 (human double minute 2) in p53wt and p53mut cells were in response to sustained increases in p53. CONCLUSION: These data identify the specific motifs within the DBD of p53 that bind p28 and suggest that p28 inhibition of COP1 binding results in the sustained, post-translational increase in p53 levels and subsequent inhibition of cancer cell growth independent of an HDM2 pathway.


Assuntos
Azurina/farmacologia , Fragmentos de Peptídeos/farmacologia , Proteína Supressora de Tumor p53/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Sequência de Aminoácidos , Animais , Azurina/química , Azurina/metabolismo , Linhagem Celular Tumoral , Regulação para Baixo/efeitos dos fármacos , Inibidores Enzimáticos/metabolismo , Inibidores Enzimáticos/farmacologia , Feminino , Humanos , Masculino , Camundongos , Camundongos Nus , Modelos Moleculares , Simulação de Dinâmica Molecular , Dados de Sequência Molecular , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/metabolismo , Ligação Proteica/efeitos dos fármacos , Domínios e Motivos de Interação entre Proteínas/efeitos dos fármacos , Domínios e Motivos de Interação entre Proteínas/fisiologia , Proteína Supressora de Tumor p53/antagonistas & inibidores , Proteína Supressora de Tumor p53/química , Ubiquitina-Proteína Ligases/antagonistas & inibidores , Ensaios Antitumorais Modelo de Xenoenxerto
3.
Nutr Metab Cardiovasc Dis ; 23(6): 505-10, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22402064

RESUMO

BACKGROUND AND AIMS: Several studies have reported that the ectonucleotide pyrophosphatase phosphodiesterase 1 (ENPP1) K121Q polymorphism (rs1044498) interacts with increased adiposity in affecting glucose homeostasis and insulin sensitivity. Conversely, one would expect that the amelioration of glucose homeostasis observed after weight loss is modulated by the ENPP1 K121Q polymorphism. The aim of our study was to test such hypothesis, in non-diabetic overweight-obese individuals. METHODS AND RESULTS: Two hundred eleven non-diabetic overweight-obese individuals were studied. Body mass index (BMI), fasting glucose, homeostasis model assessment of insulin resistance (HOMA-IR index) and lipid levels were obtained before and after 6-week lifestyle intervention (LI; diet and exercise) and their changes calculated as baseline minus 6-week values. LI decreased BMI, glucose, HOMA-IR and triglyceride levels (p < 0.001 for all). No difference across genotype groups (160 KK and 51 KQ or QQ - named as XQ - individuals) was observed in these changes. In a multivariate model, BMI changes predicted fasting glucose changes (ß = 0.139 mmol/L (2.50 mg/dl) for 1 unit BMI change, p = 0.005). This correlation was not significant among KK individuals (ß = 0.082; p = 0.15), while much steeper and highly significant among XQ individuals (ß = 0.336; p = 0.00008) (p-value for Q121-by-weight loss interaction = 0.047). CONCLUSION: Individuals carrying the ENPP1 Q121 variant are highly responsive to the effect of weight loss on fasting glucose. This reinforces the previously suggested hypothesis that the Q121 variant interacts with adiposity in modulating glucose homeostasis.


Assuntos
Adiposidade , Glicemia/análise , Diester Fosfórico Hidrolases/genética , Polimorfismo Genético , Pirofosfatases/genética , Redução de Peso , Adulto , Índice de Massa Corporal , HDL-Colesterol/sangue , Diabetes Mellitus , Dieta , Exercício Físico , Jejum , Feminino , Genótipo , Homeostase , Humanos , Resistência à Insulina , Estilo de Vida , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Obesidade/sangue , Obesidade/genética , Sobrepeso/sangue , Sobrepeso/genética , Diester Fosfórico Hidrolases/metabolismo , Pirofosfatases/metabolismo , Triglicerídeos/sangue
4.
Eur Rev Med Pharmacol Sci ; 27(24): 12141-12152, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38164876

RESUMO

OBJECTIVE: Post-COVID-19 is a syndrome defined by signs and symptoms present until 12 weeks after COVID-19, lasting for more than 8 weeks, not explained by an alternative diagnosis. The present study aimed to assess whether the cardiovascular risk (CVR) of patients with COVID-19 correlates with symptoms and changes in respiratory function parameters in post-COVID-19. The association between CVR and the severity of acute disease was also considered. PATIENTS AND METHODS: Between 21/04/21-01/09/21, we enrolled 1,782 consecutive patients with COVID-19. We divided these subjects into (i) 4 levels, based on the severity of COVID-19 (home care; hospitalized/no oxygen therapy; hospitalized/oxygen therapy; hospitalized/NIV-ICU), (ii) 2 levels, according to CVR calculated with the European Society of Cardiology SCORE tables (low-intermediate risk; high or very high risk). All subjects underwent a 3-month follow-up considering post-COVID-19 symptoms. RESULTS: In post-COVID-19 patients, high or very-high CVR was associated with (i) increased risk of hospitalization for COVID-19 (p<0.0001), (ii) higher prevalence of severe clinical manifestations and ICU admission (p<0.0001), (iii) development of post-COVID-19 (p<0.0001) and (iv) increased risk of a larger post-COVID-19 burden of disease. CONCLUSIONS: We found a statistically significant association between CVR, severity of COVID-19, and post-COVID-19 syndrome three months after the end of acute disease.


Assuntos
COVID-19 , Doenças Cardiovasculares , Humanos , Síndrome de COVID-19 Pós-Aguda , SARS-CoV-2 , Doença Aguda , Doenças Cardiovasculares/epidemiologia , Fatores de Risco , Fatores de Risco de Doenças Cardíacas
5.
J Endocrinol Invest ; 35(9): 853-8, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22293170

RESUMO

AIM: We investigated inpatients with and without Type 2 diabetes mellitus, aged over 60 yr, to compare their vitamin D status and calcium homeostatic parameters. MATERIALS AND METHODS: We studied 140 patients consecutively admitted to our Internal Medicine Unit during the year 2010 (61 from November to April, 79 from May to October). The sample encompassed 70 patients with and 70 without diabetes. At admission we measured serum calcium (Ca), phosphate (P), sodium (Na), potassium (K), creatinine (Cr), alkaline phosphatase total activity (AP), albumin adjusted serum calcium (Caalb adj), 25 hydroxy-vitamin D (25OHD), PTH, and 24-h urinary Na/Cr (uNa/Cr), K/Cr (uK/Cr), Ca/Cr (uCa/Cr), P/Cr (uP/Cr) ratios, and calcium excretion (Ca ex). RESULTS: 25OHD levels of patients with and without diabetes did not significantly differ. In patients without diabetes recruited from November to April, 25OHD levels were significantly lower than those from May to October, whilst patients with diabetes did not show a significant seasonal variation. PTH had opposite non-significant seasonal variations, and negatively correlated with 25OHD in both groups of patients. This correlation was lost after adjusting for age and body mass index in patients with diabetes. These inpatients had higher serum P and lower uP/Cr, according to lower PTH. Their serum glucose negatively correlated with uCa/Cr and Ca ex, contrary to inpatients with other diseases. Instead, uCa/Cr and Ca ex correlated with uNa/Cr only in patients without diabetes. CONCLUSIONS: Inpatients with diabetes did differ from those with other disorders for vitamin D status and calcium-phosphate homeostatic mechanism.


Assuntos
Cálcio/metabolismo , Diabetes Mellitus Tipo 2/fisiopatologia , Homeostase , Pacientes Internados/estatística & dados numéricos , Vitamina D/análogos & derivados , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fosfatos/análise , Estações do Ano , Vitamina D/sangue
6.
Minerva Chir ; 66(1): 63-72, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21389926

RESUMO

AIM: To evaluate the use of equine-derived bone grafts in the treatment of bone loss in a heterogeneous clinical case series. METHODS: The study population was 48 patients (29 males and 19 females; mean age, 49 years; range, 9-84); the orthopedic defect site was located on the right side in 22 and on the left side in 26 cases. The graft material was antigen-free equine-derived collagen bone cleaned with an enzymatic treatment. RESULTS: Clinical and radiographic healing times were virtually similar; graft osseointegration needed from two to three months longer to heal. CONCLUSION: The outcome after grafting with an equine-derived bone substitute was satisfactory. Further study is needed to demonstrate its statistically significant effectiveness in the treatment of orthopedic defects like those in this series.


Assuntos
Substitutos Ósseos/uso terapêutico , Transplante Ósseo , Fixação Interna de Fraturas/métodos , Ortopedia/métodos , Transplante Heterólogo , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Criança , Feminino , Cavalos , Humanos , Masculino , Pessoa de Meia-Idade , Osseointegração , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem
7.
Eur Rev Med Pharmacol Sci ; 25(8): 3342-3349, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33928622

RESUMO

OBJECTIVE: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) identified in China, in December 2019 determines COronaVIrus Disease 19 (COVID-19). Whether or not the virus was present in Italy earlier the first autochthonous COVID-19 case was diagnosed is still uncertain. We aimed to identify anti-SARS-CoV-2 antibodies in sera collected from 4th November 2019 to 9th March 2020, in order to assess the possible spread of the virus in Italy earlier than the first official national diagnosis. PATIENTS AND METHODS: Anti-SARS-CoV-2 antibodies were evaluated in retrospective serum samples from 234 patients with liver diseases (Hep-patients) and from 56 blood donors (BDs). We used two rapid serologic tests which were confirmed by a validated chemoluminescence assay. RESULTS: Via rapid tests, we found 10/234 (4.3%) IgG-positive and 1/234 (0.4%) IgM-positive cases in the Hep-patient group. Two/56 (3.6%) IgG-positive and 2/56 (3.6%) IgM-positive cases were detected in BD group. Chemoluminescence confirmed IgG-positivity in 3 Hep-patients and 1 BD and IgM-positivity in 1 Hep-patient. RNAemia was not detected in any of the subjects, rendering the risk of transfusion transmission negligible. CONCLUSIONS: Our results suggest an early circulation of SARS-CoV-2 in Italy, before the first COVID-19 cases were described in China. Rapid tests have multiple benefits; however, a confirmation assay is required to avoid false positive results.


Assuntos
Anticorpos Antivirais/imunologia , COVID-19/epidemiologia , Imunoglobulina G/imunologia , Imunoglobulina M/imunologia , Idoso , Doadores de Sangue , COVID-19/diagnóstico , COVID-19/imunologia , Teste Sorológico para COVID-19 , Feminino , Humanos , Imunoensaio , Itália/epidemiologia , Hepatopatias , Medições Luminescentes , Masculino , Pessoa de Meia-Idade , RNA Viral/sangue , Estudos Retrospectivos , SARS-CoV-2/genética , SARS-CoV-2/imunologia , Testes Sorológicos , Fatores de Tempo
8.
J Exp Med ; 191(10): 1777-88, 2000 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-10811870

RESUMO

Type I interferons (IFNs) are cytokines exhibiting antiviral and antitumor effects, including multiple activities on immune cells. However, the importance of these cytokines in the early events leading to the generation of an immune response is still unclear. Here, we have investigated the effects of type I IFNs on freshly isolated granulocyte/macrophage colony-stimulating factor (GM-CSF)-treated human monocytes in terms of dendritic cell (DC) differentiation and activity in vitro and in severe combined immunodeficiency mice reconstituted with human peripheral blood leukocytes (hu-PBL-SCID) mice. Type I IFNs induced a surprisingly rapid maturation of monocytes into short-lived tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL)-expressing DCs endowed with potent functional activities, superior with respect to the interleukin (IL)-4/GM-CSF treatment, as shown by FACS((R)) analyses, mixed leukocyte reaction assays with allogeneic PBLs, and lymphocyte proliferation responses to HIV-1-pulsed autologous DCs. Type I IFN induced IL-15 production and strongly promoted a T helper cell type 1 response. Notably, injection of IFN-treated HIV-1-pulsed DCs in SCID mice reconstituted with autologous PBLs resulted in the generation of a potent primary immune response, as evaluated by the detection of human antibodies to various HIV-1 antigens. These results provide a rationale for using type I IFNs as vaccine adjuvants and support the concept that a natural alliance between these cytokines and monocytes/DCs represents an important early mechanism for connecting innate and adaptive immunity.


Assuntos
Adjuvantes Imunológicos/farmacologia , Células Dendríticas/efeitos dos fármacos , Células Dendríticas/imunologia , Interferon Tipo I/farmacologia , Monócitos/efeitos dos fármacos , Monócitos/imunologia , Sequência de Aminoácidos , Animais , Sequência de Bases , Diferenciação Celular/efeitos dos fármacos , Citocinas/genética , Primers do DNA/genética , Células Dendríticas/citologia , Expressão Gênica/efeitos dos fármacos , Fator Estimulador de Colônias de Granulócitos e Macrófagos/farmacologia , Anticorpos Anti-HIV/biossíntese , Antígenos HIV/genética , HIV-1/genética , HIV-1/imunologia , Humanos , Técnicas In Vitro , Transfusão de Leucócitos , Ativação Linfocitária , Teste de Cultura Mista de Linfócitos , Camundongos , Camundongos SCID , Dados de Sequência Molecular , Monócitos/citologia , Proteínas Recombinantes , Transplante Heterólogo
9.
J Anim Physiol Anim Nutr (Berl) ; 94(6): e374-82, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20662964

RESUMO

Soya and soybean products used in swine feeding contain genistein, a non-steroidal phyto-oestrogen which has been demonstrated to influence endocrine functions. This observation leads us to design this study to evaluate the effect of genistein on swine granulosa cell steroidogenesis and proliferation. In the attempt to unravel the genistein signal transduction mechanisms, we verified the effect of lavendustin, a Tyrosine Kinase (TK) inhibitor, and the potential involvement of NO/cGMP pathway. Finally, as angiogenesis is essential for follicle development, we tested the effect of the phyto-oestrogen on vascular endothelial growth factor production and on granulosa cell redox status, because free-radical species modulate neovascularization. Our data provide evidence that genistein interferes with granulosa cell steroidogenesis while it does not modulate cell growth: this effect could be at least partially produced by inhibiting TK-dependent signalling systems. On the contrary, NO/cGMP pathway or vascular endothelial growth factor production can be excluded as signalling mechanism involved in phyto-oestrogen effects. Remarkably, genistein stimulates hydrogen peroxide production thus potentially inhibiting follicular angiogenesis. Collectively, these results suggest that genistein consumption could potentially negatively impact swine reproductive function.


Assuntos
Genisteína/farmacologia , Células da Granulosa/efeitos dos fármacos , Suínos , Animais , Proliferação de Células , Células Cultivadas , GMP Cíclico/metabolismo , Feminino , Células da Granulosa/metabolismo , Peroxidase/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Esteroides/metabolismo , Superóxido Dismutase/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo
10.
Biophys J ; 96(12): 4814-25, 2009 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-19527641

RESUMO

The Thermomyces lanuginosa lipase has been extensively studied in industrial and biotechnological research because of its potential for triacylglycerol transformation. This protein is known to catalyze both hydrolysis at high water contents and transesterification in quasi-anhydrous conditions. Here, we investigated the Thermomyces lanuginosa lipase structure in solution in the presence of a tributyrin aggregate using 30 ns molecular-dynamics simulations. The water content of the active-site groove was modified between the runs to focus on the protein-water molecule interactions and their implications for protein structure and protein-lipid interactions. The simulations confirmed the high plasticity of the lid fragment and showed that lipid molecules also bind to a secondary pocket beside the lid. Together, these results strongly suggest that the lid plays a role in the anchoring of the protein to the aggregate. The simulations also revealed the existence of a polar channel that connects the active-site groove to the outside solvent. At the inner extremity of this channel, a tyrosine makes hydrogen bonds with residues interacting with the catalytic triad. This system could function as a pipe (polar channel) controlled by a valve (the tyrosine) that could regulate the water content of the active site.


Assuntos
Ascomicetos/enzimologia , Proteínas Fúngicas/química , Lipase/química , Triglicerídeos/química , Água/química , Sequência de Aminoácidos , Sítios de Ligação , Domínio Catalítico , Ligação de Hidrogênio , Modelos Moleculares , Dados de Sequência Molecular , Estrutura Terciária de Proteína , Alinhamento de Sequência
11.
Eur Rev Med Pharmacol Sci ; 23(19): 8506-8514, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31646582

RESUMO

OBJECTIVE: A still uncertain association between vitamin D levels and HCV chronic liver diseases has been reported. Increased levels of serum-free light chains (FLCs) and an altered k/λ FLC ratio correlate with Mixed Cryoglobulinemia (MC) vasculitis and/or B-cell non-Hodgkin's lymphoma in HCV-positive patients. We aimed to investigate the possible role of vitamin D, vitamin D Binding Protein (DBP), and FLCs levels as a tool for discriminating different stages of HCV- related MC and chronic liver diseases. PATIENTS AND METHODS: Sixty-five untreated patients were retrospectively enrolled and 21 healthy blood donors (HBD) were used as controls. Vitamin D, DBP, FLCs, and cryoglobulins levels were measured. Based on cryoglobulins, patients were divided in three subgroups (without cryoglobulins, type II, and type III). RESULTS: We didn't find any significant differences in vitamin D and DBP levels between HCV patients' main groups and HBD. Serum FLCs levels were significantly higher in HCV patients than in HBD. FLCs ratio among patients' subgroups did not reveal differences. CONCLUSIONS: Our results confirm the presence of an increased serum level of FLCs in HCV patients and suggest that nor vitamin D and DBP or FLC levels can be considered reliable biomarkers for discriminating different stages of HCV-associated chronic liver diseases and/or HCV-associated extrahepatic manifestation. We confirm that serological FLCs levels are significantly higher in patients than in HBD as a signature of B cell activation in course of HCV infection.


Assuntos
Hepatite C Crônica/sangue , Cadeias Leves de Imunoglobulina/sangue , Vitamina D/análogos & derivados , Adulto , Biomarcadores/sangue , Crioglobulinas/análise , Feminino , Hepatite C Crônica/complicações , Hepatite C Crônica/patologia , Humanos , Fígado/metabolismo , Fígado/patologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Vitamina D/sangue , Proteína de Ligação a Vitamina D/sangue
12.
Eur Rev Med Pharmacol Sci ; 23(10): 4293-4302, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31173301

RESUMO

OBJECTIVE: Monoclonal plasma cell proliferative disorders comprise a wide spectrum of diseases associated to clonal B-cell expansion. Serum protein electrophoretic profile (SPEP) and circulating free light chains (FLCs) levels are the mainstay of diseases management. Recently, soluble (s) Syndecan-1 (SDC1, CD138) produced by myeloma plasma cells has been suggested in the monitoring and follow-up of patients with myeloma. The aim of our study is to evaluate sCD138 in addition with FLCs and SPEP for the screening of patients with different evolutive disease pathways. PATIENTS AND METHODS: Sera from 73 patients with monoclonal gammopathy of undetermined significance (MGUS), 120 smoldering and 42 multiple myeloma (SMM and MM, respectively), 70 HCV-related mixed cryoglobulinemia (MC), 35 B-cell non-Hodgkin's lymphoma (B-NHL) and sera from 50 healthy donors (HD), were tested for sCD138, FLCs (assessed by means of ELISA and turbidimetric assay, respectively) and electrophoresis pattern (performed on Capillarys system) for the generation of a novel biomarker score (BS). RESULTS: Our results were grouped according to the two main lines of disease progression (vs. MM or B-NHL): in one group we found BS mean values of 0.2, 3.4, 5.3, 7.1 for HD, MGUS, SMM and MM, respectively; in the other group of 0.2, 4.4, 6.7 for HD, MC and B-NHL. CONCLUSIONS: We showed that BS mean values follow the ingravescence disease status towards the two main lines of progression to cancerous conditions; it could represent an additional useful tool in the management of screening and/or follow-up.


Assuntos
Biomarcadores Tumorais/sangue , Neoplasias de Plasmócitos/diagnóstico , Neoplasias de Plasmócitos/terapia , Sindecana-1/sangue , Adulto , Eletroforese das Proteínas Sanguíneas , Progressão da Doença , Feminino , Humanos , Masculino , Programas de Rastreamento , Gamopatia Monoclonal de Significância Indeterminada , Mieloma Múltiplo/sangue , Neoplasias de Plasmócitos/sangue , Nefelometria e Turbidimetria/métodos , Paraproteinemias/sangue , Valor Preditivo dos Testes , Prognóstico
13.
Eur Rev Med Pharmacol Sci ; 22(18): 6057-6062, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30280791

RESUMO

OBJECTIVE: Mixed Cryoglobulinemia is the most well-known Hepatitis C Virus (HCV)-associated extrahepatic manifestation. MC is both an autoimmune and B-lymphoproliferative disorder. Cryoglobulins (CGs) are classified into three groups according to immunoglobulin (Ig) composition: type I is composed of one isotype or Ig class. Type II and type III mixed CGs are immune complexes composed of polyclonal IgGs acting as autoantigens and mono, polyclonal or oligoclonal IgM with rheumatoid factor activity. IgG1 and IgG3 are the predominant subclasses involved. This study shows the simultaneous presence of IgG-RF and IgG3, supporting the hypothesis of an involvement of this subclass in the initiation of early stages of CGs. PATIENTS AND METHODS: We describe a case series of six HCV-positive patients, all of whom had peripheral neuropathy and transient ischemic attacks, presenting cryoprecipitates formed by IgG3 and IgG1. Cryoprecipitate IgG subclass research was carried out by immunofixation electrophoresis by using antisera against IgG1, IgG2, IgG3, and IgG4. RESULTS: Our six patients presented with an immunochemical pattern characterized by the mere presence of IgG1 and IgG3 subclasses with probable RF activity and one of these six patients exhibited monoclonal IgG3 in his cerebrospinal fluid. CONCLUSIONS: We can hypothesize that the IgG passage through the blood-brain barrier could have contributed to the cause of TIAs, through a mechanism involving the precipitation of circulating immune complexes formed by the two subclasses in the intrathecal vessels.


Assuntos
Crioglobulinemia/imunologia , Hepatite C/complicações , Imunoglobulina G/classificação , Doenças do Sistema Nervoso Periférico/etiologia , Idoso , Barreira Hematoencefálica/imunologia , Crioglobulinemia/etiologia , Feminino , Hepatite C/imunologia , Humanos , Imunoglobulina G/metabolismo , Masculino , Pessoa de Meia-Idade , Doenças do Sistema Nervoso Periférico/imunologia , Fator Reumatoide/metabolismo
14.
J Clin Invest ; 98(3): 650-61, 1996 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-8698856

RESUMO

Anticancer therapy with doxorubicin (DOX) and other quinone anthracyclines is limited by severe cardiotoxicity, reportedly because semiquinone metabolites delocalize Fe(II) from ferritin and generate hydrogen peroxide, thereby promoting hydroxyl radical formation and lipid peroxidation. Cardioprotective interventions with antioxidants or chelators have nevertheless produced conflicting results. To investigate the role and mechanism(s) of cardiac lipid peroxidation in a clinical setting, we measured lipid conjugated dienes (CD) and hydroperoxides in blood plasma samples from the coronary sinus and femoral artery of nine cancer patients undergoing intravenous treatments with DOX. Before treatment, CD were unexpectedly higher in coronary sinus than in femoral artery (342 +/- 131 vs 112 +/- 44 nmol/ml, mean +/- SD; P < 0.01), showing that cardiac tissues were spontaneously involved in lipid peroxidation. This was not observed in ten patients undergoing cardiac catheterization for the diagnosis of arrhythmias or valvular dysfunctions, indicating that myocardial lipid peroxidation was specifically increased by the presence of cancer. The infusion of a standard dose of 60 mg DOX/m(2) rapidly ( approximately 5 min) abolished the difference in CD levels between coronary sinus and femoral artery (134 +/- 95 vs 112 +/- 37 nmol/ml); moreover, dose fractionation studies showed that cardiac release of CD and hydroperoxides decreased by approximately 80% in response to the infusion of as little as 13 mg DOX/m(2). Thus, DOX appeared to inhibit cardiac lipid peroxidation in a rather potent manner. Corollary in vitro experiments were performed using myocardial biopsies from patients undergoing aortocoronary bypass grafting. These experiments suggested that the spontaneous exacerbation of lipid peroxidation probably involved preexisting Fe(II) complexes, which could not be sequestered adequately by cardiac isoferritins and became redox inactive when hydrogen peroxide was included to simulate DOX metabolism and hydroxyl radical formation. Collectively, these in vitro and in vivo studies provide novel evidence for a possible inhibition of cardiac lipid peroxidation in DOX-treated patients. Other processes might therefore contribute to the cardiotoxicity of DOX.


Assuntos
Antibióticos Antineoplásicos/efeitos adversos , Doxorrubicina/efeitos adversos , Coração/efeitos dos fármacos , Peroxidação de Lipídeos/efeitos dos fármacos , Neoplasias/tratamento farmacológico , Difosfato de Adenosina/farmacologia , Adulto , Idoso , Relação Dose-Resposta a Droga , Feminino , Humanos , Ferro/metabolismo , Ferro/farmacologia , Masculino , Pessoa de Meia-Idade , Miocárdio/metabolismo , Neoplasias/metabolismo
15.
J Pharm Biomed Anal ; 44(3): 711-7, 2007 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-17459644

RESUMO

The capabilities of solid-phase extraction (SPE) and matrix solid-phase dispersion (MSPD) for the determination of the hormones 17beta-estradiol, 2-hydroxyestradiol, 4-hydroxyestradiol and 2-methoxyestradiol by gas chromatography-mass spectrometry (GC-MS) in a very complex matrix like porcine follicular fluids were compared, thus proving the highest effectiveness of the SPE technique. Validation was carried out in terms of limit of quantitation (LOQ), precision, accuracy, recovery and stability. LOQ values in the low microg kg(-1) were achieved, with all the other parameters satisfying the acceptance criteria for the validation of bioanalytical methods. The applicability of the method to the determination of the hormones in porcine follicular fluids was demonstrated, thus allowing to observe an increase of the concentration of the hormones during the follicular growth.


Assuntos
Líquido Folicular/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Hormônios/análise , Folículo Ovariano/crescimento & desenvolvimento , Extração em Fase Sólida/métodos , 2-Metoxiestradiol , Animais , Estradiol/análogos & derivados , Estradiol/análise , Estradiol/química , Estrogênios de Catecol , Feminino , Hormônios/química , Estrutura Molecular , Folículo Ovariano/química , Ovário/química , Reprodutibilidade dos Testes , Suínos
16.
Sci Rep ; 7(1): 11470, 2017 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-28904402

RESUMO

In accordance with the classification of the International Agency for Research on Cancer, extremely low frequency magnetic fields (ELF-MF) are suspected to promote malignant progression by providing survival advantage to cancer cells through the activation of critical cytoprotective pathways. Among these, the major antioxidative and detoxification defence systems might be targeted by ELF-MF by conferring cells significant resistance against clinically-relevant cytotoxic agents. We investigated whether the hyperproliferation that is induced in SH-SY5Y human neuroblastoma cells by a 50 Hz, 1 mT ELF magnetic field was supported by improved defence towards reactive oxygen species (ROS) and xenobiotics, as well as by reduced vulnerability against both H2O2 and anti-tumor ROS-generating drug doxorubicin. ELF-MF induced a proliferative and survival advantage by activating key redox-responsive antioxidative and detoxification cytoprotective pathways that are associated with a more aggressive behavior of neuroblastoma cells. This was coupled with the upregulation of the major sirtuins, as well as with increased signaling activity of the erythroid 2-related nuclear transcription factor 2 (NRF2). Interestingly, we also showed that the exposure to 50 Hz MF as low as 100 µT may still be able to alter behavior and responses of cancer cells to clinically-relevant drugs.


Assuntos
Campos Magnéticos , Neuroblastoma/metabolismo , Neuroblastoma/patologia , Oxirredução , Biomarcadores , Linhagem Celular Tumoral , Doxorrubicina/metabolismo , Humanos , Peróxido de Hidrogênio/metabolismo , Inativação Metabólica , Fator 2 Relacionado a NF-E2/metabolismo , Gradação de Tumores , Neuroblastoma/etiologia , Estresse Oxidativo , Espécies Reativas de Oxigênio/metabolismo , Sirtuína 1/metabolismo , Sirtuína 3/metabolismo
17.
Oncoimmunology ; 6(11): e1356964, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29147614

RESUMO

Although promising, the clinical benefit provided by dendritic cell (DC)-based vaccines is still limited and the choice of the optimal antigen formulation is still an unresolved issue. We have developed a new DC-based vaccination protocol for aggressive and/or refractory lymphomas which combines the unique features of interferon-conditioned DC (IFN-DC) with highly immunogenic tumor cell lysates (TCL) obtained from lymphoma cells undergoing immunogenic cell death. We show that treatment of mantle cell lymphoma (MCL) and diffuse large B-cell lymphoma (DLBCL) cell lines with 9-cis-retinoic acid and IFNα (RA/IFNα) induces early membrane exposure of Calreticulin, HSP70 and 90 together with CD47 down-regulation and enhanced HMGB1 secretion. Consistently, RA/IFNα-treated apoptotic cells and -TCLs were more efficiently phagocytosed by DCs compared to controls. Notably, cytotoxic T cells (CTLs) generated with autologous DCs pulsed with RA/IFNα-TCLs more efficiently recognized and specifically lysed MCL or DLBCL cells or targets loaded with several HLA-A*0201 cyclin D1 or HLA-B*0801 survivin epitopes. These cultures also showed an expansion of Th1 and Th17 cells and an increased Th17/Treg ratio. Moreover, DCs loaded with RA/IFNα-TCLs showed enhanced functional maturation and activation. NOD/SCID mice reconstituted with human peripheral blood lymphocytes and vaccinated with autologous RA/IFNα-TCL loaded-IFN-DCs showed lymphoma-specific T-cell responses and a significant decrease in tumor growth with respect to mice treated with IFN-DC unpulsed or loaded with untreated TCLs. This study demonstrates the feasibility and efficacy of the use of RA/IFNα to generate a highly immunogenic TCL as a suitable tumor antigen formulation for the development of effective anticancer DC-based vaccines.

18.
Int J Immunopathol Pharmacol ; 19(1): 57-66, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16569340

RESUMO

UNLABELLED: Insulin-like growth factor-1 (IGF-1) is involved in regulating the Th-1/Th-2 balance, favoring the development of the Th-2 compartment which enhances fibrosis, one of the main characteristics of Chronic Lung Disease (CLD) in premature newborns. Limited data is available concerning a possible association between early epithelial lining fluid (ELF) concentrations of IGF-1 (total and free forms), IGF-binding protein-3 (IGFBP-3), beta2-microglobulin and subsequent development of CLD in preterm neonates. If neutropenic, preterm neonates are frequently treated with recombinant human granulocyte colony stimulating factor (rhG-CSF). The objective of the study was to correlate ELF concentrations of IGF-1 and beta2 microglobulin during the first week of life both in non-neutropenic and in rhGCSF-treated neutropenic preterm neonates, with subsequent development in CLD. Thirty preterm neonates with Respiratory Distress Syndrome (6 with neutropenia) were studied. Eleven out of 24 non-neutropenic preterm infants (46%) and all of the six neutropenic subjects (100%) developed CLD. With the exception of first day values, there was a clear similarity in the behaviors of assayed molecules between non-neutropenic and neutropenic patients developing CLD. Non-neutropenic patients without CLD showed significantly lower values of free IGF-1 and beta2M both on days 1 and 3. Total IGF-I and cell counts were different only on the 3rd day. CONCLUSIONS: 1) the mechanisms leading to CLD might be mediated by high levels of IGF-family molecules soon after birth 2) beta2M could be a marker of increased bronchoalveolar lavage fluid cellularity with potential inflammatory properties 3) G-CSF treatment induces an increased synthesis of IGF-1 molecules by cells recruited in the lung, with possible enhancement of the fibrogenic mechanisms.


Assuntos
Células Epiteliais/metabolismo , Fator Estimulador de Colônias de Granulócitos/uso terapêutico , Recém-Nascido Prematuro/metabolismo , Fator de Crescimento Insulin-Like I/biossíntese , Fibrose Pulmonar/tratamento farmacológico , Fibrose Pulmonar/metabolismo , Microglobulina beta-2/biossíntese , Líquido da Lavagem Broncoalveolar/citologia , Contagem de Células , Infecções por Chlamydia/tratamento farmacológico , Infecções por Chlamydia/microbiologia , Doença Crônica , Células Epiteliais/efeitos dos fármacos , Humanos , Recém-Nascido , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/metabolismo , Neutropenia/tratamento farmacológico , Neutropenia/patologia , Fibrose Pulmonar/microbiologia , Proteínas Recombinantes , Infecções por Ureaplasma/tratamento farmacológico , Infecções por Ureaplasma/microbiologia , Ureaplasma urealyticum
20.
Cancer Res ; 58(24): 5795-802, 1998 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-9865738

RESUMO

The tumorigenicity of transplantable tumor cells in mice is reduced by transduction with cytokine genes, including IFN-alpha and interleukin (IL) 12. Although T cells are considered important in tumor rejection, the mechanism by which genetically modified tumor cells stimulate the immune system has not been examined. In this study, the in vivo proliferation of T-cell subsets in mice transplanted with cytokine-producing syngeneic tumor cells was assessed by administering the DNA precursor bromodeoxyuridine. The injection of viable cells producing IFN-alpha or IL-12 caused a marked proliferation of CD8+ T lymphocytes in both the spleen and lymph nodes. Proliferation was most prominent among memory-phenotype CD44hi CD8+ T cells. In contrast, proliferation of CD8+ T cells did not occur in mice injected with control cells or with cells expressing IL-4, granulocyte colony-stimulating factor, or IFN-gamma. Pulse-chase studies in mice injected with IFN-alpha-producing cells showed that a proportion of proliferating CD8+ T cells survived for at least 70 days, suggesting that long-lived memory cells are induced using such an approach. In summary, these results, together with previous studies on the host immune reactivity triggered by the injection of tumor cells expressing IFN-alpha, represent a strong rationale for considering IFN-alpha as a powerful T-cell adjuvant for the generation of more effective cancer vaccines.


Assuntos
Adenocarcinoma/imunologia , Linfócitos T CD8-Positivos/imunologia , Neoplasias do Colo/imunologia , Receptores de Hialuronatos/imunologia , Interferon-alfa/imunologia , Neoplasias Mamárias Experimentais/imunologia , Animais , Linfócitos T CD4-Positivos/imunologia , Ativação Linfocitária , Camundongos , Camundongos Endogâmicos BALB C , Transplante de Neoplasias , Transfecção
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA