Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 83
Filtrar
Mais filtros

País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
Eur J Neurol ; 27(4): 633-643, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31814224

RESUMO

BACKGROUND AND PURPOSE: Autoimmune encephalitides (AE) include a spectrum of neurological disorders whose diagnosis revolves around the detection of neuronal antibodies (Abs). Consensus-based diagnostic criteria (AE-DC) allow clinic-serological subgrouping of AE, with unclear prognostic implications. The impact of AE-DC on patients' management was studied, focusing on the subgroup of Ab-negative-AE. METHODS: This was a retrospective multicenter study on patients fulfilling AE-DC. All patients underwent Ab testing with commercial cell-based assays (CBAs) and, when available, in-house assays (immunohistochemistry, live/fixed CBAs, neuronal cultures) that contributed to defining final categories. Patients were classified as Ab-positive-AE [N-methyl-d-aspartate-receptor encephalitis (NMDAR-E), Ab-positive limbic encephalitis (LE), definite-AE] or Ab-negative-AE (Ab-negative-LE, probable-AE, possible-AE). RESULTS: Commercial CBAs detected neuronal Abs in 70/118 (59.3%) patients. Testing 37/48 Ab-negative cases, in-house assays identified Abs in 11 patients (29.7%). A hundred and eighteen patients fulfilled the AE-DC, 81 (68.6%) with Ab-positive-AE (Ab-positive-LE, 40; NMDAR-E, 32; definite-AE, nine) and 37 (31.4%) with Ab-negative-AE (Ab-negative-LE, 17; probable/possible-AE, 20). Clinical phenotypes were similar in Ab-positive-LE versus Ab-negative-LE. Twenty-four/118 (20.3%) patients had tumors, and 19/118 (16.1%) relapsed, regardless of being Ab-positive or Ab-negative. Ab-positive-AE patients were treated earlier than Ab-negative-AE patients (P = 0.045), responded more frequently to treatments (92.3% vs. 65.6%, P < 0.001) and received second-line therapies more often (33.3% vs. 10.8%, P = 0.01). Delays in first-line therapy initiation were associated with poor response (P = 0.022; odds ratio 1.02; confidence interval 1.00-1.04). CONCLUSIONS: In-house diagnostics improved Ab detection allowing better patient management but was available in a patient subgroup only, implying possible Ab-positive-AE underestimation. Notwithstanding this limitation, our findings suggest that Ab-negative-AE and Ab-positive-AE patients share similar oncological profiles, warranting appropriate tumor screening. Ab-negative-AE patients risk worse responses due to delayed and less aggressive treatments.


Assuntos
Encefalite/diagnóstico , Doença de Hashimoto/diagnóstico , Neurônios/imunologia , Fenótipo , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Encefalite/imunologia , Feminino , Doença de Hashimoto/imunologia , Humanos , Imuno-Histoquímica , Lactente , Masculino , Pessoa de Meia-Idade , Receptores de N-Metil-D-Aspartato/imunologia , Estudos Retrospectivos , Adulto Jovem
2.
Eur J Neurol ; 26(7): 992-999, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30714278

RESUMO

BACKGROUND AND PURPOSE: Acquired neuromyotonia can occur in patients with thymoma, alone or in association with myasthenia gravis (MG), but the clinical prognostic significance of such comorbidity is largely unknown. The clinico-pathological features were investigated along with the occurrence of neuromyotonia as predictors of tumour recurrence in patients with thymoma-associated myasthenia. METHODS: A total number of 268 patients with thymomatous MG were studied retrospectively. Patients with symptoms of spontaneous muscle overactivity were selected for autoantibody testing using immunohistology for neuronal cell-surface proteins and cell-based assays for contactin-associated protein 2 (CASPR2), leucine-rich glioma inactivated 1 (LGI1), glycine receptor and Netrin-1 receptor antibodies. Neuromyotonia was diagnosed according to the presence of typical electromyography abnormalities and/or autoantibodies against LGI1/CASPR2. RESULTS: Overall, 33/268 (12%) MG patients had a thymoma recurrence. Five/268 (2%) had neuromyotonia, four with typical autoantibodies, including LGI1 (n = 1), CASPR2 (n = 1) or both (n = 2). Three patients had Netrin-1 receptor antibodies, two with neuromyotonia and concomitant CASPR2+LGI1 antibodies and one with spontaneous muscle overactivity without electromyography evidence of neuromyotonia. Thymoma recurrence was more frequent in those with (4/5, 80%) than in those without (28/263, 10%, P < 0.001) neuromyotonia. Neuromyotonia preceded the recurrence in 4/5 patients. In univariate analysis, predictors of thymoma recurrence were age at thymectomy [odds ratio (OR) 0.95, 95% confidence interval (CI) 0.93-0.97], Masaoka stage ≥IIb (OR 10.73, 95% CI 2.38-48.36) and neuromyotonia (OR 41.78, 95% CI 4.71-370.58). CONCLUSIONS: De novo occurrence of neuromyotonia in MG patients with previous thymomas is a rare event and may herald tumour recurrence. Neuronal autoantibodies can be helpful to assess the diagnosis. These observations provide pragmatic risk stratification for tumour vigilance in patients with thymomatous MG.


Assuntos
Síndrome de Isaacs/complicações , Miastenia Gravis/complicações , Timoma/complicações , Neoplasias do Timo/complicações , Adulto , Autoanticorpos/sangue , Eletromiografia , Feminino , Humanos , Masculino , Proteínas de Membrana/imunologia , Pessoa de Meia-Idade , Miastenia Gravis/sangue , Recidiva Local de Neoplasia , Netrina-1/imunologia , Estudos Retrospectivos , Timoma/sangue , Neoplasias do Timo/sangue
3.
Eur J Neurol ; 26(4): 639-650, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30471162

RESUMO

BACKGROUND AND PURPOSE: Patients with a history of brain radiotherapy can experience acute stroke-like syndromes related to the delayed effects of brain radiation, including stroke-like migraine attacks after radiation therapy syndrome, peri-ictal pseudoprogression and acute late-onset encephalopathy after radiation therapy syndrome. The aim of this study was to collect evidence on the long-term outcome and treatment of these conditions, whose knowledge is undermined by their rarity and fragmented description. METHODS: Cases were collected, both prospectively and retrospectively, amongst six neuro-oncology departments. Inclusion criteria were as follows: (i) history of brain radiotherapy (completed at least 6 months before the acute episode); (ii) new onset of acute/subacute neurological symptoms; (iii) exclusion of all etiologies unrelated to brain irradiation. A review of current literature on stroke-like syndromes was performed to corroborate our findings. RESULTS: Thirty-two patients with acute neurological conditions attributed to the delayed effects of radiation were identified, including 26 patients with stroke-like syndromes. Patients with stroke-like syndromes commonly presented with a mosaic of symptoms, including focal deficits (77%), encephalopathy (50%), seizures (35%) and headache (35%). Seventy-three percent of them had acute consistent magnetic resonance imaging alterations. Treatment included high-dose steroids in 65% of cases. Twenty-two patients recovered completely (85%). Sixteen patients (62%) experienced relapses (median follow-up 3.5 years). A literature review identified 87 additional stroke-like cases with similar characteristics. CONCLUSIONS: Stroke-like events related to brain irradiation may be associated with permanent sequelae. Steroids are often administered on empirical grounds, as they are thought to accelerate recovery. Relapses are common, highlighting the need to elaborate adequate prevention strategies.


Assuntos
Encéfalo/efeitos da radiação , Irradiação Craniana/efeitos adversos , Transtornos de Enxaqueca/etiologia , Acidente Vascular Cerebral/etiologia , Adulto , Encéfalo/patologia , Progressão da Doença , Feminino , Seguimentos , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Transtornos de Enxaqueca/patologia , Estudos Retrospectivos , Acidente Vascular Cerebral/patologia
4.
J Appl Microbiol ; 121(5): 1268-1274, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27489131

RESUMO

AIMS: The purpose of this study was to isolate, characterize and determine the structure and the antibacterial activities of a bacteriocin produced by Carnobacterium maltaromaticum CPN, a strain isolated from unpasteurized milk Camembert cheese. METHODS AND RESULTS: This bacteriocin, termed maltaricin CPN, was produced at higher amounts in MRS broth at temperatures between 15°C and 25°C. It was purified to homogeneity from culture supernatant by using a simple method consisting of cation-exchange and reversed-phase chromatographies. Mass spectrometry showed that maltaricin was a 4427·29 Da bacteriocin. Its amino acid sequence was determined by Edman degradation which showed that it had close similarity with bacteriocins of the class IIa. Maltaricin CPN consisted in fact of 44 unmodified amino acids including two cysteine residues at positions 9 and 14 linked by a disulphide bond. The antimicrobial activity of maltaricin CPN covered a range of bacteria, with strong activity against many species of Gram-positive bacteria, especially the food-borne pathogen Listeria monocytogenes, but no activity against Gram-negative ones. CONCLUSIONS: In the studied conditions, C. maltaromaticum CPN produced a new class IIa bacteriocin with strong anti-Listeria activity. SIGNIFICANCE AND IMPACT OF THE STUDY: The study covers the purification and the structural characterization of a new bacteriocin produced by strain C. maltaromaticum CPN isolated from Camembert cheese. Its activity against strains of L. monocytogenes and higher production rates at relatively low temperatures show potential technological applications to improve the safety of refrigerated food.


Assuntos
Antibacterianos/química , Bacteriocinas/química , Bacteriocinas/farmacologia , Carnobacterium/metabolismo , Queijo/microbiologia , Sequência de Aminoácidos , Animais , Antibacterianos/biossíntese , Antibacterianos/farmacologia , Bacteriocinas/biossíntese , Bacteriocinas/classificação , Carnobacterium/isolamento & purificação , Bactérias Gram-Positivas/efeitos dos fármacos , Listeria monocytogenes/efeitos dos fármacos
5.
J Appl Microbiol ; 116(1): 134-44, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24016102

RESUMO

AIMS: To investigate cell determinants of resistance to gastric acidity in Lactobacillus plantarum using comparative proteomics. METHODS AND RESULTS: Among ten Lact. plantarum strains that were tested for their acid resistance in vitro, three strains with different phenotypes were selected for comparative proteomic analysis: LC 804 (resistant), CIP A159 (intermediate) and CECT 4185 (sensitive). Constitutive differences between whole-cell proteomes of the three strains were studied. Among the differentially expressed proteins between strains, 17 have previously been reported to be involved in acid resistance processes. The effect of a low-pH exposure on these proteomic patterns was investigated, which led to the identification of five putative determinants of acid resistance (heat-shock protein GrpE, methionine synthase and 30S ribosomal protein S2) or sensitivity (phosphotransacetylase and adenylosuccinate synthase). Analysis also revealed three additional proteins involved in cell envelope biogenesis (3-oxoacyl-synthase II, dTDP-glucose 4,6-dehydratase and dTDP-4-dehydrorhamnose 3,5-epimerase) likely to be key factors of intrinsic acid tolerance in Lact. plantarum. CONCLUSIONS: The approach used in this study enabled the identification of potential markers of acid tolerance in Lact. plantarum, which may serve for phenotyping and screening purposes. SIGNIFICANCE AND IMPACT OF THE STUDY: The present work represents a further step towards the identification of bacterial biomarkers for each particular probiotic feature.

6.
Neurol Sci ; 32(5): 899-902, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21234774

RESUMO

HIV-related acute inflammatory leukoencephalopathy of undetermined origin (AIL) is characterized by abrupt onset of symptoms generally associated with focal brain lesions and inflammatory CSF findings. A previously asymptomatic 31-year-old HIV+ woman presented with acute cognitive difficulties, right hemiparesis and dysphasia. Brain MRI showed a large contrast-enhancing lesion in the left frontal lobe; brain biopsy revealed an inflammatory process. No etiological agent was found in blood, CSF or brain tissue. The patient was given systemic steroids and gammaglobulins and put on HAART. Clinical conditions progressively and completely recovered. Further brain MRI showed the shrinkage of the lesion with no contrast enhancement. Our case could be classified as AIL in HIV resembling ADEM pattern and highlights the importance of taking into consideration. ADEM in the diagnostic process of HIV-related leukoencephalopathy even if the typical features are lacking, as immunodeficiency could modify both presentation and disease course.


Assuntos
Infecções por HIV/complicações , Soropositividade para HIV/complicações , Leucoencefalopatias/virologia , Adulto , Progressão da Doença , Feminino , Infecções por HIV/patologia , Soropositividade para HIV/patologia , Humanos , Leucoencefalopatias/patologia
7.
Neurol Sci ; 32(5): 833-9, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21630038

RESUMO

The introduction of highly active antiretroviral therapy does not seem to have altered the incidence of progressive multifocal leukoencephalopathy (PML) in HIV infection. Moreover, the occurrence of a HIV-related leukoencephalopathy, called not determined leukoencephalopaties (NDLE), has been reported. As neuropsychological impairment remains highly prevalent in HIV infection, the aim of this study is to describe the neuropsychological profile of PML and NDLE patients, analyzing the time-related changes. Clinical and neuropsychological data from 32 patients (17 PML, 15 NDLE) were compared with two control groups: (1) asymptomatic HIV+ patients without magnetic resonance imaging evidence of leukoencephalopathy; (2) age-/gender-/education-matched healthy subjects. Patients with rapidly worsening PML were significantly impaired on all neuropsychological tests, while PML with more benign course and NDLE groups showed a dysexecutive pattern of impairment. Asymptomatic HIV+ subjects showed mild and isolated cognitive deficits, without functional impact. Cognitive impairment should therefore be considered a key feature from HIV infection diagnosis.


Assuntos
Infecções por HIV/psicologia , Vírus JC/isolamento & purificação , Leucoencefalopatia Multifocal Progressiva/psicologia , Adulto , Idoso , Terapia Antirretroviral de Alta Atividade , Feminino , Infecções por HIV/tratamento farmacológico , Infecções por HIV/virologia , Humanos , Leucoencefalopatia Multifocal Progressiva/tratamento farmacológico , Leucoencefalopatia Multifocal Progressiva/virologia , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos
8.
Int J Immunopathol Pharmacol ; 23(3): 693-700, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20943038

RESUMO

HIV-related acute inflammatory leukoencephalopathy of undetermined origin (AIL) has been anecdotally described in literature as being responsible for cognitive and motor deficits. We carried out a review of all the cases of AIL published in literature. Articles were selected according to 2 criteria: acute onset of symptoms; undetermined aetiology and non-fulfilment of multiple sclerosis diagnostic criteria. They were then analyzed in terms of clinical, biological and instrumental features, therapy, diagnostic classification and prognosis. Although rare (21 patients out of about 4,000 publications), AIL is of particular interest, as the comprehension of its mechanisms could give some insight into the direct and immune-mediated actions of HIV within the brain. All the reported patients share several clinical, histopathological, radiological and CSF features, leading to hypothesize a similar aetiopathogenetic mechanism. Conversely, we observed a high heterogeneity of treatment and diagnostic classification, which could have conditioned the broad prognostic variability. The absence of a defined aetiology leads to consider these forms as a particular subgroup of not determined leucoencephalopathies (NDLE), with both MRI and histological pattern dominated by inflammation as distinctive feature.


Assuntos
Encefalite/etiologia , Infecções por HIV/complicações , Leucoencefalopatias/etiologia , Complexo AIDS Demência/patologia , Doença Aguda , Fármacos Anti-HIV/uso terapêutico , Encéfalo/patologia , Encefalite/tratamento farmacológico , Encefalite/patologia , Infecções por HIV/tratamento farmacológico , Infecções por HIV/patologia , Soropositividade para HIV , Humanos , Leucoencefalopatias/tratamento farmacológico , Leucoencefalopatias/patologia , Imageamento por Ressonância Magnética , Medula Espinal/patologia , Terminologia como Assunto , Tomografia Computadorizada por Raios X
9.
Int J Androl ; 32(2): 123-30, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17916181

RESUMO

In the present study, we analysed the expression of Fas ligand (FasL) and its cognate receptor Fas in 14 seminomatous testicular germ cell tumours (TGCT) and six normal testicular tissues obtained following orchiectomy. Tissue samples have been processed to prepare either total RNA or protein extracts or fixed and embedded in paraffin for immunohistochemistry (IHC) experiments. Quantitative RT-PCR experiments demonstrated in TGCT a significant (p < 0.01) increase of the FasL mRNA expression of 21.1 +/- 5.4 fold, with respect to normal tissues. On the contrary, in the same cancer tissues, the levels of Fas mRNA were significantly (p < 0.01) reduced to 0.27 +/- 0.06 fold. These observations were confirmed in western blot experiments showing a significant increase of FasL and a concomitant decrease of Fas proteins in testicular cancer tissues, with respect to normal testis. Moreover, IHC experiments showed a strong FasL immuno-reactivity in six out of eight TGCT samples analysed, while Fas immuno-positivity was found in cancer cells of only two TGCT tissues. In addition, in all tumour samples, infiltrating lymphocytes were Fas positive. However, no correlation could be observed between Fas or FasL mRNA variations and clinical parameters such as patient's age, TNM stage or tumour size. We also compared the serum levels of soluble FasL (sFasL) of 15 patients affected by seminomatous TGCT, of four patients with non-seminomatous TGCT and six age-matched healthy males. No significant differences in sFasL serum level could be identified. In conclusion, our data demonstrated that the majority of seminomas are characterized by an increased expression of FasL and a concomitant reduction of Fas, with respect to human normal testis, and that sFasL serum level is not a tumour marker for patients affected by TGCT.


Assuntos
Proteína Ligante Fas/biossíntese , Seminoma/metabolismo , Neoplasias Testiculares/metabolismo , Receptor fas/biossíntese , Adulto , Biomarcadores Tumorais/biossíntese , Biomarcadores Tumorais/sangue , Progressão da Doença , Proteína Ligante Fas/sangue , Proteína Ligante Fas/genética , Humanos , Masculino , Pessoa de Meia-Idade , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Adulto Jovem , Receptor fas/genética
10.
Spinal Cord ; 47(7): 531-7, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19104509

RESUMO

OBJECTIVE: Idiopathic transverse myelitis (I-TM) is typically monophasic, while relapsing forms are usually referred to spinal cord-restricted neuromyelitis optica (NMO), atypical multiple sclerosis (MS), or myelitis during the course of infections and connectivitis. Our objective was to evaluate the frequency of recurrent I-TM; to clarify the nosology of these forms through comparison with NMO and post-infectious TM (P-TM). DESIGN: Prospective cohort study on patients presenting with I-TM was carried out inpatients of Infectious and Neurologic Disease Clinics, Italy. METHODS: Over an 8-year period, we recruited 13 patients with I-TM and 16 with P-TM. The patients were followed-up for at least 3 years with repeated brain and spinal cord magnetic resonance imaging (MRI) examinations, multimodal evoked potentials and serum screen for connectivitis. Relapses were defined on clinical and imaging criteria. RESULTS: Four patients with I-TM (31%) had a relapsing course . They were all males with age >50, and severe at-onset disability. The final outcome was poor in three out of four patients. Serum NMO-immunoglobulin G was undetectable in all patients. Longitudinally extensive myelitis was not predictive of relapses. I-TM and P-TM shared clinical, cerebrospinal fluid (CSF) and MRI features, as well as a similar rate (54 vs 38%) of peripheral nervous system involvement (polyradiculoneuritis), and an identical rate of relapses (31% for both forms). CONCLUSIONS: Our series support the existence of relapsing I-TM as a disease entity that does not appear related to NMO, nor to MS, cannot be further specified and shares many features with P-TM. The likelihood of relapses was unpredictable based on clinical, CSF and MRI findings.


Assuntos
Imunoglobulinas/sangue , Mielite Transversa/diagnóstico , Adulto , Idoso , Autoanticorpos , Encéfalo/patologia , Estudos de Coortes , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Mielite Transversa/sangue , Recidiva , Estudos Retrospectivos , Testes Sorológicos , Medula Espinal/patologia , Adulto Jovem
11.
Colloids Surf B Biointerfaces ; 176: 439-448, 2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-30669103

RESUMO

The development of new packaging able to preserve sensitive biomolecules against oxidative stress is an important field. Several studies refer to antioxidant properties carried out by colloidal gold nanoparticles (AuNP). Herein, the purpose was to check whether this property is preserved when AuNP are immobilized on a glass support. After nanostructured film preparation, the physicochemical characterization proved that AuNP were well-individualized in the films with a high density of immobilization. Two radicals: ABTS•+ and DPPH• were used to investigate their antioxidant capacity. The results showed that immobilized AuNP had a preserved antioxidant capacity characterized by a different kinetic: more controlled and more prolonged but with the same efficiency (vs the same quantity of colloidal AuNP). The AuNP films demonstrated a capacity to prevent from degradation a molecule containing a thiol function. A 10-fold increase of N-acetylcysteine half-life was measured using the immobilized AuNP, highlighting the interest of the developed and adaptable support.


Assuntos
Antioxidantes/farmacologia , Embalagem de Medicamentos , Nanopartículas Metálicas/química , Acetilcisteína , Coloides/química , Nanopartículas Metálicas/ultraestrutura , Compostos de Sulfidrila/química
12.
Cephalalgia ; 28(6): 577-84, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18384413

RESUMO

A bibliographical search was conducted for papers published between 1999 and 2007 to verify the validity of International Classification of Headache Disorders (ICHD)-II criteria for the Tolosa-Hunt syndrome (THS) in terms of (i) the role of magnetic resonance imaging (MRI); (ii) which steroid treatment should be considered as adequate; and (iii) the response to treatment. Of 536 articles, 48, reporting on 62 patients, met the inclusion criteria. MRI was positive in 92.1% of the cases and it normalized after clinical resolution. There was no evidence of which steroid schedule should be considered as adequate; high-dose steroids are likely to be more effective both to induce resolution and to avoid recurrences. Pain subsided within the time limit required by the ICHD-II criteria, but signs did not. We conclude that THS diagnostic criteria can be improved on the basis of currently available data. MRI should play a pivotal role both to diagnose and to follow-up THS.


Assuntos
Classificação Internacional de Doenças , Celulite Orbitária/diagnóstico , Celulite Orbitária/tratamento farmacológico , Guias de Prática Clínica como Assunto/normas , Sinusite/diagnóstico , Sinusite/tratamento farmacológico , Síndrome de Tolosa-Hunt/diagnóstico , Síndrome de Tolosa-Hunt/tratamento farmacológico , Seio Cavernoso , Humanos , Internacionalidade , Celulite Orbitária/epidemiologia , Avaliação de Resultados em Cuidados de Saúde/métodos , Prognóstico , Sinusite/epidemiologia , Síndrome de Tolosa-Hunt/epidemiologia , Resultado do Tratamento
14.
Food Chem Toxicol ; 45(12): 2581-91, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17766022

RESUMO

Food irradiation has been considered as a safe processing technology to improve food safety and preservation, eliminating efficiently bacterial pathogens, parasites and insects. This study aims to characterize the toxicological potential of 2-alkylcyclobutanones (2-ACBs), radiolytic derivatives of triglycerides, formed uniquely upon irradiation of fat-containing food. In irradiated food they are generated proportionally to fat content and absorbed radiation dose. The cyto- and genotoxic potentials of various highly pure synthetic 2-ACBs were studied in bacteria and human cell lines. While pronounced cytotoxicity was evident in bacteria, no mutagenic activity has been revealed by the Ames test in Salmonella strains TA 97, TA 98 and TA 100. In mammalian cells genotoxicity was demonstrated mainly by the induction of DNA base lesions recognized by the Fpg protein as determined by both the Comet Assay and the Alkaline Unwinding procedure. Formation of DNA strand breaks was observed by the Alkaline Unwinding procedure but not by the Comet Assay. The extent of cytotoxicity and genotoxicity were dependent on chain length and degree of unsaturation of the fatty acid chain. Further studies will have to clarify mechanisms of action and potential relevance for human exposure situation.


Assuntos
Ciclobutanos/toxicidade , Irradiação de Alimentos , Linhagem Celular Tumoral/efeitos dos fármacos , Ciclobutanos/administração & dosagem , Dano ao DNA , Relação Dose-Resposta a Droga , Humanos , Testes de Mutagenicidade , Salmonella/efeitos dos fármacos , Salmonella/genética
15.
J Microbiol Biotechnol ; 27(1): 1-8, 2017 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-27666988

RESUMO

The production of high-value chemicals from natural resources as an alternative for petroleum-based products is currently expanding in parallel with biorefinery. The use of lignocellulosic biomass as raw material is promising to achieve economic and environmental sustainability. Filamentous fungi, particularly Aspergillus species, are already used industrially to produce organic acid as well as many enzymes. The production of lignocellulose-degrading enzymes opens the possibility for direct fungal fermentation towards organic acids such as itaconic acid (IA) and fumaric acid (FA). These acids have wide-range applications and potentially addressable markets as platform chemicals. However, current technologies for the production of these compounds are mostly based on submerged fermentation. This work showed the capacity of two Aspergillus species (A. terreus and A. oryzae) to yield both acids by solid-state fermentation and simultaneous saccharification and fermentation. FA was optimally produced at by A. oryzae in simultaneous saccharification and fermentation (0.54 mg/g wheat bran). The yield of 0.11 mg IA/g biomass by A. oryzae is the highest reported in the literature for simultaneous solid-state fermentation without sugar supplements.

16.
Cell Death Differ ; 12(2): 128-35, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15550935

RESUMO

Plant sterols are found in fruits and vegetables. Their cholesterol-lowering effect is well documented. Our study aimed at comparing antiproliferative effects of 7beta-hydroxysitosterol (7beta-OHsito) versus 7beta-hydroxycholesterol (7beta-OHchol) on the human colon cancer cell line Caco-2. When cells were exposed for 32 h to 60 microM 7beta-OHsito or to 30 microM 7beta-OHchol, both compounds caused 50% growth inhibition. Cells treated with 7beta-OHsito showed enhanced caspase-9 and -3 activities followed by DNA fragmentation. In contrast, 7beta-OHchol did not activate caspase-3 and activation of caspase-9 and DNA fragmentation were delayed. The treatment of cells with the caspase inhibitor Z-VAD.fmk retarded the 7beta-OHsito-induced apoptotic process but not that triggered by 7beta-OHchol. Our data suggest that the two compounds in spite of their structural similarities target different cellular pathways, which lead to cell death.


Assuntos
Apoptose/fisiologia , Proliferação de Células/efeitos dos fármacos , Hidroxicolesteróis/farmacologia , Sitosteroides/farmacologia , Clorometilcetonas de Aminoácidos/farmacologia , Apoptose/efeitos dos fármacos , Células CACO-2 , Caspase 3 , Caspase 9 , Inibidores de Caspase , Caspases/metabolismo , Ciclo Celular/efeitos dos fármacos , Neoplasias do Colo/patologia , Inibidores de Cisteína Proteinase/farmacologia , Fragmentação do DNA/efeitos dos fármacos , Humanos
17.
Eur J Cancer ; 42(15): 2631-8, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16928445

RESUMO

We characterised the expression of the plasminogen activators (uPA and tPA), the uPA receptor (uPAR) and the PAs inhibitors (PAI-1 and PAI-2) in human thyroid cell lines derived from normal thyroid, follicular adenoma, follicular, papillary and anaplastic carcinomas. Urokinase PA activity was detected in the supernatant of normal thyrocytes and augmented in those of all tumour cells. Quantitative RT-PCR analysis showed that uPA, uPAR and PAI-1 mRNAs increased in all carcinoma cells. Similar results were found in 13 papillary thyroid carcinoma (PTC) tissues which were mirrored in Western blot experiments. A correlation was found between tumour size and uPA mRNA increase, and higher levels of uPA and uPAR mRNAs were found in metastatic PTC. In conclusion, thyroid carcinoma cell lines and PTC overexpress uPA, uPAR and PAI-1 and the correlation of uPA and its cognate receptor with tumour size and metastasis may suggest their potential prognostic relevance in thyroid cancer.


Assuntos
Carcinoma Papilar/metabolismo , Proteínas de Neoplasias/metabolismo , Ativadores de Plasminogênio/metabolismo , Neoplasias da Glândula Tireoide/metabolismo , Western Blotting , Linhagem Celular Tumoral , Humanos , Metástase Neoplásica , Prognóstico , RNA Mensageiro/metabolismo , RNA Neoplásico/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Ativador de Plasminogênio Tipo Uroquinase/metabolismo
18.
Anticancer Res ; 26(1B): 553-8, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16739319

RESUMO

BACKGROUND: In this randomized phase III study, the effectiveness as well as the side-effects of intraarterial [i.a.] (17 patients) versus intravenous [i.v.] (16 patients) ACNU [Nimustine] administration in newly diagnosed glioblastoma, were compared. PATIENTS AND METHODS: All patients undenwent extensive surgical resection, and both groups were homogeneous for the other known risk factors. Thirty-three patients with glioblastoma were treated with ACNU at the dose of 80-100 mg/m2. Treatment was repeated every 5-8 weeks for a minimum of 2 and maximum of 14 cycles. Total survival time (TST) and to time to progression were chosen as outcome variables. RESULTS AND CONCLUSION: No significant differences in systemic and hematological toxicity between the i.a. and iv. ACNU administration routes were detected. In both groups, tolerance of the procedure was excellent. Analysis of the main outcome measured showed no significant differences between i.a. and i.v. ACNU administration: time to progression was 6 months for i.a. ACNU and 4 months for i.v. ACNU and total survival time was 17 months for i.a. ACNU and 20 months for i.v. ACNU. In spite of ACNU dose incrementation, obtained through i.a. route administration, and subsequent higher concentration in the tumor bed, no improvement could be achieved in effectiveness.


Assuntos
Antineoplásicos/administração & dosagem , Glioblastoma/tratamento farmacológico , Nimustina/administração & dosagem , Neoplasias Supratentoriais/tratamento farmacológico , Adulto , Idoso , Antineoplásicos/efeitos adversos , Feminino , Humanos , Infusões Intra-Arteriais , Infusões Intravenosas , Masculino , Pessoa de Meia-Idade , Doenças do Sistema Nervoso/induzido quimicamente , Nimustina/efeitos adversos
19.
J Neurol Sci ; 363: 182-7, 2016 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-27000248

RESUMO

Combined central and peripheral demyelination (CCPD) is rare, and current knowledge is based on case reports and small case series. The aim of our study was to describe the clinical features, diagnostic results, treatment and outcomes in a large cohort of patients with CCPD. Thirty-one patients entered this retrospective, observational, two-center study. In 20 patients (65%) CCPD presented, after an infection, as myeloradiculoneuropathy, encephalopathy, cranial neuropathy, length-dependent peripheral neuropathy, or pseudo-Guillain-Barré syndrome. Demyelinating features of peripheral nerve damage fulfilling European Federation of Neurological Societies/Peripheral Nerve Society (EFNS/PNS) electrodiagnostic criteria for CIDP were found in 23 patients (74%), and spatial dissemination of demyelinating lesions on brain MRI fulfilling the 2010 McDonald criteria for multiple sclerosis (MS) in 11 (46%). Two thirds of the patients had a relapsing or progressive disease course, usually related to the appearance of new spinal cord lesions or worsening of the peripheral neuropathy, and showed unsatisfactory responses to high-dose corticosteroids and intravenous immunoglobulins. The clinical presentation of CCPD was severe in 22 patients (71%), who were left significantly disabled. Our data suggest that CCPD has heterogeneous features and shows frequent post-infectious onset, primary peripheral nervous system or central nervous system involvement, a monophasic or chronic disease course, inadequate response to treatments, and a generally poor outcome. We therefore conclude that the current diagnostic criteria for MS and CIDP may not fully encompass the spectrum of possible manifestations of CCPD, whose pathogenesis remains largely unknown.


Assuntos
Doenças Desmielinizantes/diagnóstico por imagem , Doenças Desmielinizantes/terapia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Feminino , Seguimentos , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Polirradiculoneuropatia/diagnóstico por imagem , Polirradiculoneuropatia/terapia , Polirradiculoneuropatia Desmielinizante Inflamatória Crônica/diagnóstico por imagem , Polirradiculoneuropatia Desmielinizante Inflamatória Crônica/terapia , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem
20.
Int J Pharm ; 491(1-2): 402-8, 2015 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-26049075

RESUMO

Insulin delivery by oral route would be ideal, but has no effect, due to the harsh conditions of the gastrointestinal tract. Protection of insulin using encapsulation in self-assembled particles is a promising approach. However, the lack of stability of this kind of particles in biological environments induces a low bioavailability of encapsulated insulin after oral administration. The objective of this work was to evaluate the effect of two stabilisation strategies alone or combined, freeze-drying and cross-linking, on insulin-loaded chitosan NPs, and to determine their bioefficiency in vitro and in vivo. NPs were prepared by complex coacervation between insulin and chitosan, stabilised either by cross linking with sodium tripolyphosphate solution (TPP), by freeze-drying or both treatments. In vitro bioefficiency NP uptake was evaluated by flow cytometry on epithelial models (Caco-2/RevHT29MTX (mucus secreting cells)). In vivo, NPs were injected via catheter in the peritoneum or duodenum on insulinopenic rats. Freeze-drying increased in size and charge (+15% vs control 412 ± 7 nm; + 36 ± 0.3 mV) in comparison with cross linking which decreased NP size (-25%) without impacting the NP charge. When combined the consecutive treatments reduced NPs size and increased charges as compared to standard level. Freeze drying is necessary to prevent the destruction of NP in intestinal environment in comparison with no freeze dryed one where 60% of NP were destroyed after 2h. Additionally freeze drying combined with cross linking treatments improved bioefficiency of NP with uptake in cell increased when mucus is present. Combination of both treatment showed a protection of insulin in vivo, with a reduction of glycemia when NPs were administrated. This work showed that the combination of freeze drying and cross linking treatment is necessary to stabilize (freeze-drying) and increase bioefficiency (cross-linking) of self assembled NP in the delivery of insulin in vitro and in vivo.


Assuntos
Quitosana/química , Insulina/administração & dosagem , Nanopartículas/química , Animais , Glicemia/metabolismo , Células CACO-2 , Química Farmacêutica , Reagentes de Ligações Cruzadas , Sistemas de Liberação de Medicamentos , Desenho de Fármacos , Estabilidade de Medicamentos , Excipientes , Liofilização , Humanos , Insulina/química , Insulina/farmacologia , Masculino , Muco/metabolismo , Ratos , Ratos Wistar
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA