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1.
Int J Cosmet Sci ; 41(6): 604-612, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31529705

RESUMO

OBJECTIVE: Development of cosmetic formulations to provide a controlled release of hydrophilic active compounds from mineral medicinal waters constitutes an attractive challenge. The objective of this study was the development and the characterization of a dermocosmetic gel formulation with Cró thermal water, from Beira Interior of Portugal, as a major functional ingredient. METHODS: Concentrations of mineral chemical elements of Cró thermal water were previously determined by inductively coupled plasma-optical emission spectrometry or mass spectrometry and cytotoxicity assays using thermal water were carried out on normal human dermal fibroblasts (NHDF) cells. Then, the Cró thermal water was included (more than 90%) in a developed gel formulation that was characterized through rheological and texture analysis and submitted to stability assays during 30 days. The effects on the skin volunteers, namely skin pH, the degree of hydration, transepidermal water loss and skin relief, were evaluated through non-invasive biometric techniques. A gel formulation including purified water was used as a control. RESULTS: Cró thermal water is rich on several chemical elements in particular sodium, silica, potassium and calcium besides some trace elements, with important functions for the skin. NHDF cells adhered and proliferated in the presence of thermal water confirming the biocompatibility of the major component of the gel formulation. The developed gel formulation based on thermal water resulted in an improvement of textural parameters, comparing with the purified water-based one. Significant improvements in the cutaneous biometric parameters (degree of hydration, transepidermal water loss and skin relief) of volunteers were also registered for the gel formulation containing thermal water. CONCLUSION: This study demonstrated for the first time the potential benefits of Cró thermal water in a gel formulation to be used in cosmetic and dermatological applications.


OBJECTIF: Le développement de formulations cosmétiques permettant une libération contrôlée des substances actives hydrophiles à partir d'eaux médicinales minérales constitue un défi attractif. L'objectif de cette étude était le développement et la caractérisation d'une formulation de gel dermocosmétique avec l'eau thermale de Cró, de Beira Interior au Portugal, comme ingrédient fonctionnel majeur. MÉTHODES: Les concentrations en éléments chimiques minéraux de l'eau thermale de Cró ont étés préalablement déterminées par spectrométrie d'émission optique avec plasma couplé par induction ou spectrométrie de masse et des essais de cytotoxicité utilisant de l'eau thermale ont été réalisés sur des cellules de fibroblastes dermiques humains normaux (NHDF). Ensuite, l'eau thermale de Cró a été incluse (plus de 90%) dans une formulation de gel développée qui a été caractérisée par analyse rhéologique et texture et soumise à des tests de stabilité pendant 30 jours. Les effets sur la la peau des volontaires, à savoir le pH de la peau, le degré d'hydratation, la perte d'eau transépidermique et le relief cutané, ont été évalués à l'aide de techniques biométriques non invasives. Une formulation de gel comprenant de l'eau purifiée a été utilisée comme témoin. RÉSULTATS: L'eau thermale de Cró est riche en plusieurs éléments chimiques, en particulier le sodium, la silice, le potassium et le calcium, en plus de certains oligo-éléments, avec des fonctions importantes pour la peau. Les cellules NHDF ont adhéré et ont proliféré en présence d'eau thermale, confirmant la biocompatibilité du composant principal de la formulation du gel. La formulation de gel développée à base d'eau thermale a permis une amélioration des paramètres de texture comparée à celle à base d'eau purifiée. Des améliorations significatives des paramètres biométriques cutanés (degré d'hydratation, perte en eau transépidermique et relief cutané) des volontaires ont également été enregistrées avec la formulation en gel contenant de l'eau thermale. CONCLUSION: Cette étude a démontré pour la première fois les avantages potentiels de l'eau thermale de Cró dans une formulation de gel destinée aux applications cosmétiques et dermatologiques.


Assuntos
Cosméticos/química , Água , Administração Cutânea , Humanos , Interações Hidrofóbicas e Hidrofílicas , Portugal , Reologia
2.
Environ Geochem Health ; 39(3): 483-496, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27142760

RESUMO

Mineral natural waters and spas have been used for therapeutic purposes for centuries, with Portugal being a very rich country in thermal waters and spas that are mainly distributed by northern and central regions where Beira Interior region is located. The use of thermal waters for therapeutic purposes has always been aroused a continuous interest, being dependent on physicochemical fingerprinting of this type of waters the indication for a treatment in a specific pathological condition. In the present work, besides a literature review about the physicochemical composition of the thermal waters of the Beira Interior region and its therapeutic indications, it was carried out an exhaustive multivariate analysis-principal component analysis and cluster analysis-to assess the correlation between different physicochemical parameters and the therapeutic indications claims described for these spas and thermal waters. These statistical methods used for data analysis enables classification of thermal waters compositions into different groups, regarding to the different variable selected, making possible an interpretation of variables affecting water compositions. Actually, Monfortinho and Longroiva are clearly quite different of the others, and Cró and Fonte Santa de Almeida appear together in all analysis, suggesting a strong resemblance between these waters. Thereafter, the results obtained allow us to demonstrate the role of major components of the studied thermal waters on a particular therapeutic purpose/indication and hence based on compositional and physicochemical properties partially explain their therapeutic qualities and beneficial effects on human health. This classification agreed with the results obtained for the therapeutic indications approved by the Portuguese National Health Authority and proved to be a valuable tool for the regional typology of mineral medicinal waters, constituting an important guide of the therapeutic armamentarium for well and specific-oriented pathological disturbs.


Assuntos
Águas Minerais/análise , Fenômenos Químicos , Águas Minerais/uso terapêutico , Análise Multivariada , Portugal , Análise de Componente Principal
3.
Spinal Cord ; 54(6): 439-44, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26481712

RESUMO

STUDY DESIGN: Experimental study with rats. OBJECTIVE: To evaluate functional and histological effects of tacrolimus (FK 506) and erythropoietin (EPO) after experimental spinal cord contusion injury (SCI). SETTING: Brazil. METHODS: Wistar rats (n=60) were submitted to SCI with the NYU Impactor system. The control group received saline; the EPO group received EPO; the group EPO+FK 506 received EPO associated with tacrolimus and the group FK 506 received tacrolimus only. The Sham group underwent SCI, but did not receive any drug. Locomotor function was evaluated after SCI by BBB (Basso, Beattie and Bresnahan) weekly and by the motor-evoked potential test in 42 days. The spinal cord was histologically evaluated. RESULTS: There was a significant difference between treated and the control groups from the seventh day on for BBB scores, with no difference between the groups EPO and EPO+FK 506 by the end of the study. There were significant differences between groups for necrosis and bleeding, but not for hiperemia, degeneration and cellular infiltrate. Axon neuron count was different between all groups (P=0.001), between EPO+FK 506 and FK 506 (P=0.011) and between EPO+FK 506 and Sham (P=0.002). Amplitude was significantly different between all groups except between control and sham. For latency, there was no difference. CONCLUSIONS: This study did not reveal significant differences in the recovery of locomotor function, or in the histological and electrophysiological analysis in animals treated with EPO and tacrolimus after thoracic SCI.


Assuntos
Eritropoetina/uso terapêutico , Imunossupressores/uso terapêutico , Traumatismos da Medula Espinal/tratamento farmacológico , Traumatismos da Medula Espinal/patologia , Tacrolimo/uso terapêutico , Animais , Modelos Animais de Doenças , Potencial Evocado Motor/efeitos dos fármacos , Seguimentos , Locomoção/efeitos dos fármacos , Doenças do Sistema Nervoso/tratamento farmacológico , Doenças do Sistema Nervoso/etiologia , Ratos , Ratos Wistar , Recuperação de Função Fisiológica/efeitos dos fármacos , Traumatismos da Medula Espinal/fisiopatologia , Estatísticas não Paramétricas , Fatores de Tempo
4.
Biochim Biophys Acta ; 1838(10): 2555-67, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24976292

RESUMO

Dioctadecyldimethylammonium bromide (DODAB):Monoolein (MO) lipoplexes have mainly been studied within the range of high molar ratios of DODAB, with noticeable transfection efficiencies in the Human Embryonic Kidney (HEK, a.k.a. 293T) cell line. In this work, we intend to study the effect of high MO content on the structure and physicochemical properties of pDNA/DODAB:MO lipoplexes to achieve some correlation with their transfection efficiency. Static/Dynamic Light Scattering and Cryo-TEM imaging were used to characterize the size/morphology of DNA/DODAB:MO lipoplexes at different DODAB:MO contents (2:1, 1:1, 1:2) and charge ratios (CRs) (+/-). Nile Red fluorescence emission was performed to detect changes in microviscosity, hydration and polarity of DNA/DODAB:MO systems. Lipoplexes stability at physiological pH values and in the presence of anionic lipids was evaluated by Förster Resonance Energy Transfer (FRET). Physicochemical/structural data were complemented with transfection studies in HEK cells using the ß-galactosidase reporter gene activity assay. This work reports the coexistence of multilamellar and non-lamellar inverted phases in MO-richer lipoplexes (DODAB:MO 1:2 and 1:4), leading to transfection efficiencies comparable to those of multilamellar (DODAB-richer) lipoplexes, but at higher charge ratios [CR (+/-)=6.0] and without dose-effect response. These results may be related to the structural changes of lipoplexes promoted by high MO content.


Assuntos
DNA/química , Glicerídeos/química , Plasmídeos/química , Compostos de Amônio Quaternário/química , Células HEK293 , Humanos , Concentração de Íons de Hidrogênio , Transfecção/métodos
5.
Photochem Photobiol Sci ; 13(12): 1730-40, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25319772

RESUMO

The fluorescence properties of the new potent antitumoral methyl 3-amino-6-(benzo[d]thiazol-2-ylamino)thieno[3,2-b]pyridine-2-carboxylate in solution and when encapsulated in several different nanoliposome formulations were investigated. The compound exhibits very reasonable fluorescence quantum yields and a solvent sensitive emission in several polar and non-polar media, despite not being fluorescent in protic solvents. Fluorescence anisotropy measurements of the compound incorporated into liposomes revealed that this thienopyridine derivative can be carried in the hydrophobic region of the lipid membrane. Liposome formulations including this antitumor compound are nanometric in size, with a diameter lower than 130 nm and generally low polydispersity, and are promising for future drug delivery developments. The interaction of the compound with bovine serum albumin (BSA) and the multidrug resistance protein MDR1 was monitored by FRET, the compound acting as an energy acceptor. It was observed that the drug had a lower interaction with the MDR1 protein than with the native form of BSA, which is an important result regarding applications of this antitumoral drug.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Tienopiridinas/química , Subfamília B de Transportador de Cassetes de Ligação de ATP/química , Animais , Bovinos , Proteínas do Ovo/química , Fluorescência , Polarização de Fluorescência , Transferência Ressonante de Energia de Fluorescência , Humanos , Interações Hidrofóbicas e Hidrofílicas , Lipossomos/química , Estrutura Molecular , Nanoestruturas/química , Soroalbumina Bovina/química , Solventes/química , Espectrometria de Fluorescência
6.
Nature ; 452(7183): 88-92, 2008 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-18322534

RESUMO

Mycorrhizal symbioses--the union of roots and soil fungi--are universal in terrestrial ecosystems and may have been fundamental to land colonization by plants. Boreal, temperate and montane forests all depend on ectomycorrhizae. Identification of the primary factors that regulate symbiotic development and metabolic activity will therefore open the door to understanding the role of ectomycorrhizae in plant development and physiology, allowing the full ecological significance of this symbiosis to be explored. Here we report the genome sequence of the ectomycorrhizal basidiomycete Laccaria bicolor (Fig. 1) and highlight gene sets involved in rhizosphere colonization and symbiosis. This 65-megabase genome assembly contains approximately 20,000 predicted protein-encoding genes and a very large number of transposons and repeated sequences. We detected unexpected genomic features, most notably a battery of effector-type small secreted proteins (SSPs) with unknown function, several of which are only expressed in symbiotic tissues. The most highly expressed SSP accumulates in the proliferating hyphae colonizing the host root. The ectomycorrhizae-specific SSPs probably have a decisive role in the establishment of the symbiosis. The unexpected observation that the genome of L. bicolor lacks carbohydrate-active enzymes involved in degradation of plant cell walls, but maintains the ability to degrade non-plant cell wall polysaccharides, reveals the dual saprotrophic and biotrophic lifestyle of the mycorrhizal fungus that enables it to grow within both soil and living plant roots. The predicted gene inventory of the L. bicolor genome, therefore, points to previously unknown mechanisms of symbiosis operating in biotrophic mycorrhizal fungi. The availability of this genome provides an unparalleled opportunity to develop a deeper understanding of the processes by which symbionts interact with plants within their ecosystem to perform vital functions in the carbon and nitrogen cycles that are fundamental to sustainable plant productivity.


Assuntos
Basidiomycota/genética , Basidiomycota/fisiologia , Genoma Fúngico/genética , Micorrizas/genética , Micorrizas/fisiologia , Raízes de Plantas/microbiologia , Simbiose/fisiologia , Abies/microbiologia , Abies/fisiologia , Basidiomycota/enzimologia , Proteínas Fúngicas/classificação , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Regulação da Expressão Gênica , Genes Fúngicos/genética , Hifas/genética , Hifas/metabolismo , Micorrizas/enzimologia , Raízes de Plantas/fisiologia , Simbiose/genética
7.
Nat Genet ; 29(2): 189-93, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11586300

RESUMO

The newly recognized ataxia-ocular apraxia 1 (AOA1; MIM 208920) is the most frequent cause of autosomal recessive ataxia in Japan and is second only to Friedreich ataxia in Portugal. It shares several neurological features with ataxia-telangiectasia, including early onset ataxia, oculomotor apraxia and cerebellar atrophy, but does not share its extraneurological features (immune deficiency, chromosomal instability and hypersensitivity to X-rays). AOA1 is also characterized by axonal motor neuropathy and the later decrease of serum albumin levels and elevation of total cholesterol. We have identified the gene causing AOA1 and the major Portuguese and Japanese mutations. This gene encodes a new, ubiquitously expressed protein that we named aprataxin. This protein is composed of three domains that share distant homology with the amino-terminal domain of polynucleotide kinase 3'- phosphatase (PNKP), with histidine-triad (HIT) proteins and with DNA-binding C2H2 zinc-finger proteins, respectively. PNKP is involved in DNA single-strand break repair (SSBR) following exposure to ionizing radiation and reactive oxygen species. Fragile-HIT proteins (FHIT) cleave diadenosine tetraphosphate, which is potentially produced during activation of the SSBR complex. The results suggest that aprataxin is a nuclear protein with a role in DNA repair reminiscent of the function of the protein defective in ataxia-telangiectasia, but that would cause a phenotype restricted to neurological signs when mutant.


Assuntos
Apraxias/genética , Ataxia/genética , Proteínas de Ligação a DNA/genética , Mutação , Proteínas Nucleares/genética , Músculos Oculomotores/fisiopatologia , Dedos de Zinco , Sequência de Aminoácidos , Apraxias/complicações , Ataxia/complicações , Sequência de Bases , Primers do DNA , Proteínas de Ligação a DNA/química , Heterozigoto , Homozigoto , Humanos , Dados de Sequência Molecular , Proteínas Nucleares/química , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Homologia de Sequência de Aminoácidos
8.
Biochim Biophys Acta ; 1808(10): 2440-9, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21787746

RESUMO

DNA/Cationic liposome complexes (lipoplexes) have been widely used as non-viral vectors for transfection. Neutral lipids in liposomal formulation are determinant for transfection efficiency using these vectors. In this work, we studied the potential of monoolein (MO) as helper lipid for cellular transfection. Lipoplexes composed of pDNA and dioctadecyldimethylammonium bromide (DODAB)/1-monooleoyl-rac-glycerol (MO) at different molar ratios (4:1, 2:1 and 1:1) and at different cationic lipid/DNA ratios were investigated. The physicochemical properties of the lipoplexes (size, charge and structure), were studied by Dynamic Light Scattering (DLS), Zeta Potential (ζ) and cryo-transmission electron microscopy (cryo-TEM). The effect of MO on pDNA condensation and the effect of heparin and heparan sulphate on the percentage of pDNA release from the lipoplexes were also studied by Ethidium Bromide (EtBr) exclusion assays and electrophoresis. Cytotoxicity and transfection efficiency of these lipoplexes were evaluated using 293T cells and compared with the golden standard helper lipids 1,2-dioleoyl-sn-glycero-3-hosphoethanolamine (DOPE) and cholesterol (Chol) as well as with a commercial transfection agent (Lipofectamine™ LTX). The internalization of transfected fluorescently-labeled pDNA was also visualized using the same cell line. The results demonstrate that the presence of MO not only increases pDNA compactation efficiency, but also affects the physicochemical properties of the lipoplexes, which can interfere with lipoplex-cell interactions. The DODAB:MO formulations tested showed little toxicity and successfully mediated in vitro cell transfection. These results were supported by fluorescence microscopy studies, which illustrated that lipoplexes were able to access the cytosol and deliver pDNA to the nucleus. DODAB:MO-based lipoplexes were thus validated as non-toxic, efficient lipofection vectors for genetic modification of mammalian cells. Understanding the relation between structure and activity of MO-based lipoplexes will further strengthen the development of these novel delivery systems.


Assuntos
Vetores Genéticos , Glicerídeos/química , Compostos de Amônio Quaternário/química , Transfecção , Microscopia Crioeletrônica , Lipossomos , Microscopia Eletrônica de Transmissão , Microscopia de Fluorescência
9.
Insect Mol Biol ; 21(2): 235-45, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22243654

RESUMO

Coptotermes formosanus is one of the most destructive wood-feeding termites. To understand the molecular mechanisms that regulate the development of the termite, a normalized C. formosanus cDNA library was constructed using mixed RNA isolated from workers, soldiers, nymphs and alates of both sexes. The sequencing of this library generated 131 636 expressed sequence tags (ESTs) and 25 939 assembled unigenes. The carbohydrate-active enzymes (CAZymes) revealed in this library were analysed in the present report. A total of 509 putative CAZymes were identified. Diverse cellulolytic enzymes were uncovered from both the host termite and from symbionts harboured by the termite, which were possibly the result of the high efficiency of cellulose utilization. CAZymes associated with trehalose biosynthetic and metabolic pathways were also identified, which are potential regulators of the physiological activities of trehalose, an important insect blood sugar. Representative CAZyme coding genes in glycoside hydrolase family 1 (GH1) were quantitatively analysed. The results showed that the five GH1 ß-glucosidase genes were expressed differentially among different castes and one of them was female alate-specific. Overall, the normalized EST library provides a comprehensive genetic resource of C. formosanus and will serve a diverse range of research areas. The CAZymes represent one of the repositories of enzymes useful for physiological studies and applications in sugar-based biofuel production.


Assuntos
Metabolismo dos Carboidratos , Isópteros/enzimologia , Predomínio Social , Transcriptoma , Sequência de Aminoácidos , Animais , Celulases/metabolismo , Esterases/genética , Esterases/metabolismo , Etiquetas de Sequências Expressas , Feminino , Expressão Gênica , Biblioteca Gênica , Glicosídeo Hidrolases/genética , Glicosídeo Hidrolases/metabolismo , Glicosiltransferases/genética , Glicosiltransferases/metabolismo , Isópteros/genética , Masculino , Dados de Sequência Molecular , Polissacarídeo-Liases/genética , Polissacarídeo-Liases/metabolismo , Alinhamento de Sequência , Trealose/biossíntese
10.
Eur J Neurol ; 17(1): 124-8, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19659750

RESUMO

BACKGROUND AND PURPOSE: The relative frequency of the different autosomal dominant cerebellar ataxia (ADCA) varies widely amongst different geographic locations. Here we describe a series of 45 ADCA families from Portugal. METHODS: Patients with progressive cerebellar dysfunction of autosomal dominant transmission underwent a clinical examination protocol and genetic testing for spinocerebellar ataxia (SCA)1 to Machado-Joseph disease (MJD)/SCA3, SCA6, SCA7, SCA10, SCA12, SCA17 and dentatorubral-pallidoluysian atrophy (DRPLA). We registered the clinical characteristics and frequency of each type of ataxia. RESULTS: MJD/SCA3 was the most frequent ADCA (26 families, 57.8% of all families), followed by DRPLA (5 families, 11.2%), SCA7 (2 families, 4.4%), SCA2 and SCA1 (1 family each, 2.2% each); 10 families (22.2%) had no molecular diagnosis. SCA1 and SCA7 patients had African ancestry. DRPLA patients had Portuguese ancestry and were characterized by prominent anticipation and a variable combination of epilepsy, extra-pyramidal symptoms and dementia. Ophtalmoparesis, slow saccades and retinopathy were most distinctive of SCA3, SCA2 and SCA7 cases, respectively. CONCLUSIONS: MJD/SCA3 was the most common ADCA in this group of families. The high frequency of DRPLA and presence of SCA1 and SCA7 cases was unexpected. The presence of these rarer ADCA types probably reflects migration phenomena, posing a challenge for differential diagnosis.


Assuntos
Ataxia Cerebelar/classificação , Ataxia Cerebelar/genética , Transtornos Cromossômicos/genética , Genes Dominantes/genética , Adolescente , Adulto , População Negra/genética , Ataxia Cerebelar/epidemiologia , Análise Mutacional de DNA , Feminino , Frequência do Gene/genética , Testes Genéticos , Genótipo , Humanos , Doença de Machado-Joseph/diagnóstico , Doença de Machado-Joseph/genética , Masculino , Epilepsias Mioclônicas Progressivas/diagnóstico , Epilepsias Mioclônicas Progressivas/genética , Portugal/epidemiologia , Portugal/etnologia , Prevalência , População Branca/genética , Adulto Jovem
11.
J Med Primatol ; 39(3): 166-9, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20236218

RESUMO

Congenital aplasia of the hallux (big toe) was observed in seven adult and infant members of a free-ranging group of silvery marmosets (Mico argentatus) in the Alter do Chão savannah of central Amazonia. Apparently heritable, the condition was more common in males (80%) than females (50%) but was found in no other members of the population. Animals with the condition presented normal behaviour.


Assuntos
Callithrix/anormalidades , Deformidades Congênitas do Pé/veterinária , Hallux/anormalidades , Animais , Feminino , Masculino
12.
Brain ; 132(Pt 10): 2688-98, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19696032

RESUMO

Ataxia with oculomotor apraxia type 2 (AOA2) is an autosomal recessive disease due to mutations in the senataxin gene, causing progressive cerebellar ataxia with peripheral neuropathy, cerebellar atrophy, occasional oculomotor apraxia and elevated alpha-feto-protein (AFP) serum level. We compiled a series of 67 previously reported and 58 novel ataxic patients who underwent senataxin gene sequencing because of suspected AOA2. An AOA2 diagnosis was established for 90 patients, originating from 15 countries worldwide, and 25 new senataxin gene mutations were found. In patients with AOA2, median AFP serum level was 31.0 microg/l at diagnosis, which was higher than the median AFP level of AOA2 negative patients: 13.8 microg/l, P = 0.0004; itself higher than the normal level (3.4 microg/l, range from 0.5 to 17.2 microg/l) because elevated AFP was one of the possible selection criteria. Polyneuropathy was found in 97.5% of AOA2 patients, cerebellar atrophy in 96%, occasional oculomotor apraxia in 51%, pyramidal signs in 20.5%, head tremor in 14%, dystonia in 13.5%, strabismus in 12.3% and chorea in 9.5%. No patient was lacking both peripheral neuropathy and cerebellar atrophy. The age at onset and presence of occasional oculomotor apraxia were negatively correlated to the progression rate of the disease (P = 0.03 and P = 0.009, respectively), whereas strabismus was positively correlated to the progression rate (P = 0.03). An increased AFP level as well as cerebellar atrophy seem to be stable in the course of the disease and to occur mostly at or before the onset of the disease. One of the two patients with a normal AFP level at diagnosis had high AFP levels 4 years later, while the other had borderline levels. The probability of missing AOA2 diagnosis, in case of sequencing senataxin gene only in non-Friedreich ataxia non-ataxia-telangiectasia ataxic patients with AFP level > or =7 microg/l, is 0.23% and the probability for a non-Friedreich ataxia non-ataxia-telangiectasia ataxic patient to be affected with AOA2 with AFP levels > or =7 microg/l is 46%. Therefore, selection of patients with an AFP level above 7 microg/l for senataxin gene sequencing is a good strategy for AOA2 diagnosis. Pyramidal signs and dystonia were more frequent and disease was less severe with missense mutations in the helicase domain of senataxin gene than with missense mutations out of helicase domain and deletion and nonsense mutations (P = 0.001, P = 0.008 and P = 0.01, respectively). The lack of pyramidal signs in most patients may be explained by masking due to severe motor neuropathy.


Assuntos
Apraxia Ideomotora/fisiopatologia , Ataxia/complicações , Ataxia/patologia , Oftalmoplegia/fisiopatologia , Adulto , Idade de Início , Apraxia Ideomotora/genética , Ataxia/genética , Estudos de Coortes , DNA Helicases , Progressão da Doença , Feminino , Genótipo , Humanos , Imageamento por Ressonância Magnética , Masculino , Enzimas Multifuncionais , Mutação de Sentido Incorreto/genética , Oftalmoplegia/genética , Fenótipo , RNA Helicases/genética , RNA Helicases/metabolismo , Estudos Retrospectivos , alfa-Fetoproteínas/genética , alfa-Fetoproteínas/metabolismo
13.
Genet Mol Res ; 9(1): 539-44, 2010 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-20391338

RESUMO

The glutathione S-transferases (GSTs), a family of phase II isozymes, detoxify several carcinogens. Genetic variations in GSTs have been associated with increased risk for cancer due to a heritable deficiency in detoxification pathways for environmental carcinogens. Conflicting findings have been reported about the association between constitutive GST polymorphisms and gliomas in different populations. The present case-control study examined 78 patients with primary glioma and 347 controls from Rio de Janeiro. DNA was isolated from whole blood, and four genetic polymorphisms (GSTM1, GSTM3, GSTT1, and GSTP1) were determined by PCR-RFLP. The distributions of the genotypic frequencies of these polymorphisms did not differ significantly between cases and controls and were as expected by Hardy-Weinberg equilibrium (P > 0.05). Risk analysis did not show an association between GSTs and primary glioma, suggesting that these polymorphisms do not influence the risk of primary glioma, at least in this population in Rio de Janeiro, Brazil.


Assuntos
Predisposição Genética para Doença , Glioma/enzimologia , Glioma/genética , Glutationa Transferase/genética , Polimorfismo de Nucleotídeo Único/genética , Brasil , Estudos de Casos e Controles , Glutationa S-Transferase pi/genética , Humanos , Razão de Chances
14.
Acta Neurol Scand ; 119(2): 113-8, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18664244

RESUMO

OBJECTIVES: The hereditary spastic paraplegias (HSP) are a genetically and clinically heterogeneous group of neurodegenerative disorders, mainly characterized by a progressive spasticity and weakness of the lower limbs. Mutations in the SPG4 and SPG3A genes are responsible for approximately 50% of autosomal dominant HSP. To genetically diagnose the Portuguese families with HSP, mutation analysis was performed for the SPG4 and SPG3A genes. PATIENTS AND METHODS: Analysis was performed by polymerase chain reaction, followed by denaturing high performance liquid chromatography (DHPLC), in 61 autosomal dominant (AD)-HSP families and 19 unrelated patients without family history. RESULTS: Ten novel mutations were identified: one in the SPG3A and nine in the SPG4 genes; three known mutations in the SPG4 were also found. Most of the novel mutations were frameshift or nonsense (80%), resulting in a dysfunctional protein. CONCLUSIONS: The SPG4 and SPG3A analysis allowed the identification of 10 novel mutations and the genetic diagnosis of approximately a quarter of our AD-HSP families.


Assuntos
Adenosina Trifosfatases/genética , GTP Fosfo-Hidrolases/genética , Paraplegia/genética , Idade de Início , Sequência de Aminoácidos , Cromatografia Líquida de Alta Pressão , Família , Feminino , Proteínas de Ligação ao GTP , Genes Dominantes , Humanos , Masculino , Proteínas de Membrana , Dados de Sequência Molecular , Mutação , Paraplegia/epidemiologia , Linhagem , Reação em Cadeia da Polimerase , Análise de Sequência de Proteína , Espastina
16.
J Phys Condens Matter ; 30(23): 235804, 2018 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-29697405

RESUMO

In this paper we studied the reversal magnetization of La1-x Sr x Fe0.5Cr0.5O3-δ (x = 0, 0.1 and 0.2) samples produced by combustion synthesis. The structural analysis was carried out by x-ray diffraction with Rietveld analysis. These analyses revealed that all samples have an orthorhombic structure with space group Pbnm (62) and that the Sr-doping induces a decrease of the lattice parameter. The x-ray photoelectron spectroscopy analysis indicates that the Sr-doping favor the change of the valence states of the Fe3+ to Fe4+. The magnetization as a function of the temperature reveals an unusual magnetic behavior with a reversal of magnetization. The increase of the Sr content induces a decrease of the temperature where occurs an inversion of the magnetization and do the value of the magnetization at 5 K more negative. This effect is attributed to the increase of the concentration of Fe4+ with increasing of the Sr content. The Fe and Cr with a valence of 4+ act as paramagnetic impurities in the antiferromagnetic lattice and are responsible for the changes in the magnetic behavior.

17.
FEBS Lett ; 463(3): 277-80, 1999 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-10606737

RESUMO

The distribution of cellulosomal cohesin domains among the sequences currently compiled in various sequence databases was investigated. Two cohesin domains were detected in two consecutive open reading frames (ORFs) of the recently sequenced genome of the archaeon Archaeoglobus fulgidus. Otherwise, no cohesin-like sequence could be detected in organisms other than those of the Eubacteria. One of the A. fulgidus cohesin-containing ORFs also harbored a dockerin domain, but the additional modular portions of both genes are undefined, both with respect to sequence homology and function. It is currently unclear what function(s) the putative cohesin and dockerin-containing proteins play in the life cycle of this organism. In particular, since A. fulgidus contains no known glycosyl hydrolase gene, the presence of a cellulosome can be excluded. The results suggest that cohesin and dockerin signature sequences cannot be used alone for the definitive identification of cellulosomes in genomes.


Assuntos
Archaeoglobus fulgidus/química , Indóis/química , Proteínas Nucleares/química , Propionatos/química , Sequência de Aminoácidos , Archaeoglobus fulgidus/genética , Proteínas de Ciclo Celular , Proteínas Cromossômicas não Histona , Proteínas Fúngicas , Dados de Sequência Molecular , Fases de Leitura Aberta , Filogenia , Alinhamento de Sequência , Coesinas
18.
Arch Neurol ; 55(10): 1341-4, 1998 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9779663

RESUMO

BACKGROUND: Machado-Joseph disease (MJD) is an autosomal dominant cerebellar ataxia of adult onset with a high prevalence in the islands of Azores (Portugal). The genetic epidemiological studies presently under way in these islands are based on the genealogical reconstruction of the affected families, thus partially depending on the reference of patients using family history. A considerable effort has been made to obtain genealogies that are as complete as possible, making use of different types of data. The utility of the death causes contained in the death registers of the patients with MJD was determined in this study. OBJECTIVES: To estimate the extent to which the cause of death reported in the death register can confirm other reports of an individual's status for the disease (ie, oral information), and to determine the accuracy of the death certificates in listing MJD in patients whose disease was clinically diagnosed. DESIGN: Case-control study. METHODS: The death registers of 113 patients with MJD (82 whose disease was identified by history and 31 whose disease was clinically diagnosed) were examined and compared with those of controls matched by sex and date and place of death. RESULTS: There were significant differences in the causes of death between cases and controls, both for those whose disease was identified by history (chi(2) = 51.69, P < .001) and for those whose disease was identified by examination (chi(2) = 27.78, P = .004). However, the cause of death was in accord with the presence of the disease in only 40% of the cases reported as being identified only by family history. In the cases in which the disease was clinically diagnosed, only nearly 38% of the registers provided reliable information as to MJD being the direct cause of death. CONCLUSIONS: The fact that only nearly 40% of the patients with clinically confirmed MJD had a cause of death compatible with MJD precludes the use of cause of death as a means of identifying affected individuals in the Azorean MJD pedigrees.


Assuntos
Doença de Machado-Joseph/mortalidade , Adulto , Idoso , Estudos de Casos e Controles , Causas de Morte , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Portugal/epidemiologia
19.
Arch Neurol ; 58(11): 1821-7, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11708990

RESUMO

BACKGROUND: Direct detection of the gene mutation allows for the confirmation of the clinical diagnosis of Machado-Joseph disease (MJD), the most frequent cause of autosomal dominant spinocerebellar ataxia worldwide. OBJECTIVE: To address the main difficulties in our national MJD predictive testing program. The first was the emergence of intermediate alleles, for which it is not yet possible to determine whether they will cause disease. The second was the issue of homoallelism, ie, homozygosity for 2 normal alleles with exactly the same (CAG)(n) length, which occurs in about 10% of all test results. METHODS: A large pedigree with 1 affected patient carrying a 71 and a 51 CAG repeat and 2 asymptomatic relatives carrying the 51 CAG repeat and normal-size alleles underwent clinical and molecular studies. Intragenic haplotypes for these alleles were determined. A representative sample of the healthy population in the region was obtained to assess the distribution of the normal (CAG)(n) length. We established the genotype for 4 intragenic polymorphisms in the gene for MJD (MJD1) in 21 homoallelic individuals, to distinguish their 2 normal chromosomes. In addition, we developed a new Southern blot method to completely exclude cases of nonamplification of expanded alleles in the homoallelic individuals. RESULTS: The study of the family in which the 51 CAG repeat was found suggests that the allele is apparently not associated with disease. These intermediate alleles were not present in a large sample of the healthy population from the same region. Intragenic polymorphisms allowed distinction of the 2 different normal alleles in all cases of homoallelism. The absence of an expanded allele was also confirmed by Southern blot. CONCLUSIONS: We propose an improved protocol for molecular testing for MJD. These strategies, developed to overcome the practical difficulties mostly in the presymptomatic and prenatal diagnosis of MJD, should prove useful for other polyglutamine-related disorders.


Assuntos
Testes Genéticos/métodos , Doença de Machado-Joseph/diagnóstico , Doença de Machado-Joseph/genética , Proteínas do Tecido Nervoso/genética , Adulto , Idoso , Alelos , Ataxina-3 , Sequência de Bases , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Mutação , Proteínas Nucleares , Linhagem , Polimorfismo Genético/genética , Portugal , Proteínas Repressoras , Expansão das Repetições de Trinucleotídeos
20.
Arch Neurol ; 58(2): 201-5, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11176957

RESUMO

BACKGROUND: The recessive ataxias are a heterogeneous group of neurodegenerative disorders characterized by cerebellar ataxia associated with a number of different neurologic, ophthalmologic, or general signs. They are often difficult to classify in clinical terms, except for Friedreich ataxia, ataxia-telangiectasia, and a relatively small group of rare conditions for which the molecular basis has already been defined. OBJECTIVES: To study the clinical presentation and to define diagnostic criteria in a group of Portuguese patients with ataxia and ocular apraxia, an autosomal recessive form without the essential clinical and laboratory features of ataxia-telangiectasia. PATIENTS AND METHODS: We reviewed 22 patients in 11 kindreds, identified through a systematic survey of hereditary ataxias being conducted in Portugal. RESULTS: Age at onset ranged from 1 to 15 years, with a mean of 4.7 years. The duration of symptoms at the time of last examination varied from 5 to 58 years. All patients presented with progressive cerebellar ataxia, the characteristic ocular apraxia, and a peripheral neuropathy. Associated neurologic signs included dystonia, scoliosis, and pes cavus. Magnetic resonance imaging was performed in 16 patients, all of whom showed cerebellar atrophy. CONCLUSIONS: Ataxia with ocular apraxia may be more frequent than postulated before, and may be identified clinically using the following criteria: (1) autosomal recessive transmission; (2) early onset (for most patients in early childhood); (3) combination of cerebellar ataxia, ocular apraxia, and early areflexia, with later appearance of the full picture of peripheral neuropathy; (4) absence of mental retardation, telangiectasia, and immunodeficiency; and (5) the possibility of a long survival, although with severe motor handicap.


Assuntos
Apraxias/diagnóstico , Transtornos da Motilidade Ocular/diagnóstico , Degenerações Espinocerebelares/diagnóstico , Adolescente , Adulto , Idade de Início , Apraxias/complicações , Apraxias/epidemiologia , Atrofia , Cerebelo/patologia , Criança , Distonia/complicações , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Transtornos da Motilidade Ocular/complicações , Transtornos da Motilidade Ocular/epidemiologia , Linhagem , Doenças do Sistema Nervoso Periférico/complicações , Portugal , Estudos Retrospectivos , Degenerações Espinocerebelares/complicações , Degenerações Espinocerebelares/epidemiologia
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