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1.
Front Oncol ; 14: 1380648, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38606091

RESUMO

Introduction: In monoclonal B cell lymphocytosis (MBL) and chronic lymphocytic leukemia (CLL), the expansion of malignant B cells disrupts the normal homeostasis and interactions between B cells and T cells, leading to immune dysregulation. CD20+ T cells are a subpopulation of T cells that appear to be involved in autoimmune diseases and cancer. Methods: Here, we quantified and phenotypically characterized CD20+ T cells from MBL subjects and CLL patients using flow cytometry and correlated our findings with the B-cell receptor mutational status and other features of the disease. Results and discussion: CD20+ T cells were more represented within the CD8+ T cell compartment and they showed a predominant memory Tc1 phenotype. CD20+ T cells were less represented in MBL and CLL patients vs healthy controls, particularly among those with unmutated IGVH gene. The expansion of malignant B cells was accompanied by phenotypic and functional changes in CD20+ T cells, including an increase in follicular helper CD4+ CD20+ T cells and CD20+ Tc1 cells, in addition to the expansion of the TCR Vß 5.1 in CD4+ CD20+ T cells in CLL.

2.
Animals (Basel) ; 14(6)2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38539981

RESUMO

Traumatic nerve injuries are common lesions that affect several hundred thousand humans, as well as dogs and cats. The assessment of nerve regeneration through animal models may provide information for translational research and future therapeutic options that can be applied mutually in veterinary and human medicine, from a One Health perspective. This review offers a hands-on vision of the non-invasive and conservative approaches to peripheral nerve injury, focusing on the role of neurorehabilitation in nerve repair and regeneration. The peripheral nerve injury may lead to hypersensitivity, allodynia and hyperalgesia, with the possibility of joint contractures, decreasing functionality and impairing the quality of life. The question remains regarding how to improve nerve repair with surgical possibilities, but also considering electrical stimulation modalities by modulating sensory feedback, upregulation of BDNF, GFNF, TrKB and adenosine monophosphate, maintaining muscle mass and modulating fatigue. This could be improved by the positive synergetic effect of exercises and physical activity with locomotor training, and other physical modalities (low-level laser therapy, ultrasounds, pulsed electromagnetic fields, electroacupuncture and others). In addition, the use of cell-based therapies is an innovative treatment tool in this field. These strategies may help avoid situations of permanent monoplegic limbs that could lead to amputation.

3.
Dent J (Basel) ; 11(11)2023 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-37999022

RESUMO

The Invisalign® system (SmartForce® G8) aims to guarantee aesthetics and provide good orthodontic treatment results. Dentoalveolar expansion is possible with clear aligners and can be used to correct dentoalveolar crossbite, resolve crowding or modify the arch shape. Despite the treatment's effectiveness, there is still disagreement among professionals concerning its true clinical potential. This study aimed to analyze the effectiveness and predictability of coronal tooth expansion movement in permanent dentition in patients who had completed the first phase of treatment with Invisalign® orthodontic aligners. MATERIALS AND METHODS: The tooth movement tables of 75 previously selected cases were analyzed in terms of dental-arch width and expansion efficiency, through the Invisalign® platform, considering the pre-treatment (T0), planned treatment (TP) and post-treatment models (T1) using ClinCheck Pro® 6.0 software. All patients were treated by an orthodontic specialist and Invisalign® Diamond Provider in a private practice (T.P.). RESULTS: Difference between T1 and T0: for each maxillary and mandibular measurement, there was a statistically significant difference between pre- and post-aligner treatment values. The greatest amount of expansion occurred in both the upper and the lower premolars. Difference between TP and T1: for each maxillary measurement, statistically significant differences were verified for the molar and canine. At the mandibular level, statistically significant differences were only verified in the first molar. CONCLUSIONS: The Invisalign® clear aligners are effective for simultaneous intra-arch expansion in both jaws.

4.
Dent J (Basel) ; 11(8)2023 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-37623282

RESUMO

Coronal torque is one of the key factors in orthodontic treatment. An adequate torque value has an impact on aesthetics and soft tissue profile. The aim of this quantitative, comparative and observational longitudinal cohort study was to analyze the efficacy of the maxillary central incisor coronal torque in the Invisalign® system and evaluate the relation between coronal torque movement and patient's facial biotype. In total, 27 patients were selected. The planned movements (TP) were obtained from the Invisalign Doctor Site® using mathematical formulas that consider the T0 measurements. Pre-treatment (T0) and after full use of the first set of aligners (T1) scanners were evaluated using Geomagic® Control X TM by superimposing T0 and T1 models using a transverse plane and the long axis of the tooth crown. IBM® SPSS® software was used for statistical purposes. We found statistically significant differences between T0 and T1 in pro-inclination and retro-inclination, as well as between achieved and planned values in pro-inclination (p = 0.011). We verified that hyperdivergent clinical cases presented higher mean values of coronal torque, and hypodivergent cases presented lower values. In pro-inclination, the differences between the planned and achieved values were greater in hypodivergent cases and smaller in hyperdivergent cases. In retro-inclination, the differences between the planned and achieved values were greater in normodivergent cases and smaller in hypodivergent cases. This study highlights that inefficacy is more accentuated in pro-inclination. Aligners are an effective tool for producing coronal repercussions of torque movement, being more effective in retro-inclination.

5.
Front Vet Sci ; 10: 1192744, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37520009

RESUMO

Introduction: Degenerative myelopathy (DM) is a neurodegenerative spinal cord disease with upper motor neurons, with progressive and chronic clinical signs, similar to amyotrophic lateral sclerosis (ALS). DM has a complex etiology mainly associated with SOD1 gene mutation and its toxic role, with no specific treatment. Daily intensive rehabilitation showed survival time near 8 months but most animals are euthanized 6-12 months after clinical signs onset. Methods: This prospective controlled blinded cohort clinical study aims to evaluate the neural regeneration response ability of DM dogs subjected to an intensive neurorehabilitation protocol with mesenchymal stem cells (MSCs) transplantation. In total, 13 non-ambulatory (OFS 6 or 8) dogs with homozygous genotype DM/DM and diagnosed by exclusion were included. All were allocated to the intensive neurorehabilitation with MSCs protocol (INSCP) group (n = 8) or to the ambulatory rehabilitation protocol (ARP) group (n = 5), which differ in regard to training intensity, modalities frequency, and MSCs transplantation. The INSCP group was hospitalized for 1 month (T0 to T1), followed by MSCs transplantation (T1) and a second month (T2), whereas the ARP group was under ambulatory treatment for the same 2 months. Results: Survival mean time of total population was 375 days, with 438 days for the INSCP group and 274 for the ARP group, with a marked difference on the Kaplan-Meier survival analysis. When comparing the literature's results, there was also a clear difference in the one-sample t-test (p = 0.013) with an increase in time of approximately 70%. OFS classifications between groups at each time point were significantly different (p = 0.008) by the one-way ANOVA and the independent sample t-test. Discussion: This INSCP showed to be safe, feasible, and a possibility for a long progression of DM dogs with quality of life and functional improvement. This study should be continued.

6.
Cells ; 12(5)2023 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-36899923

RESUMO

Nanomaterials offer a broad spectrum of applications in biomedicine. The shapes of gold nanoparticles could modulate tumor cell behavior. Spherical (AuNPsp), stars (AuNPst) and rods (AuNPr) shapes of polyethylene glycol coated-gold nanoparticles (AuNPs-PEG) were synthesized. Metabolic activity, cellular proliferation, and reactive oxygen species (ROS) were measured and the impact of AuNPs-PEG in metabolic enzymes function was evaluated by RT-qPCR in PC3, DU145, and LNCaP prostate cancer cells. All AuNPs were internalized, and the different morphologies of AuNPs showed to be an essential modulator of metabolic activity. For PC3 and DU145, the metabolic activity of AuNPs was found to rank in the following order from lowest to highest: AuNPsp-PEG, AuNPst-PEG, and AuNPr-PEG. Regarding LNCaP cells, the AuNPst-PEG were less toxic, followed by AuNPsp-PEG and AuNPr-PEG, but it seems not to be dose-dependent. The proliferation was lower in AuNPr-PEG in PC3 and DU145 cells but was stimulated around 10% in most conditions (0.001-0.1 mM) in LNCaP cells (not statistically significant). For 1 mM, LNCaP cells showed a significant decrease in proliferation only for AuNPr-PEG. The outcomes of the current study demonstrated that different AuNPs conformations influence cell behavior, and the correct size and shape must be chosen considering its final application in the field of nanomedicine.


Assuntos
Nanopartículas Metálicas , Nanosferas , Nanotubos , Neoplasias da Próstata , Masculino , Humanos , Ouro
7.
Life (Basel) ; 12(9)2022 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-36143384

RESUMO

Raw brewers' spent grain (BSG), a by-product of beer production and produced at a large scale, presents a composition that has been shown to have potential as feedstock for several biological processes, such as polyhydroxyalkanoates (PHAs) production. Although the high interest in the PHA production from waste, the bioconversion of BSG into PHA using microbial mixed cultures (MMC) has not yet been explored. This study explored the feasibility to produce PHA from BSG through the enrichment of a mixed microbial culture in PHA-storing organisms. The increase in organic loading rate (OLR) was shown to have only a slight influence on the process performance, although a high selectivity in PHA-storing microorganisms accumulation was reached. The culture was enriched on various PHA-storing microorganisms, such as bacteria belonging to the Meganema, Carnobacterium, Leucobacter, and Paracocccus genera. The enrichment process led to specialization of the microbiome, but the high diversity in PHA-storing microorganisms could have contributed to the process stability and efficiency, allowing for achieving a maximum PHA content of 35.2 ± 5.5 wt.% (VSS basis) and a yield of 0.61 ± 0.09 CmmolPHA/CmmolVFA in the accumulation assays. Overall, the production of PHA from fermented BSG is a feasible process confirming the valorization potential of the feedstock through the production of added-value products.

9.
Rev Port Cir Cardiotorac Vasc ; 26(2): 159-162, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31476820

RESUMO

Pulmonary sequestration (PS) is a rare congenital malformation, even more when its arterial supply is a coronary artery. We present a case of a 68-year-old man admitted in the emergency room with an acute coronary syndrome and no evidence of significant coronary disease. Instead, he had an abnormal branch from the circumflex coronary artery nourishing a mass in the left lower pulmonary lobe. A coronary steal phenomenon was proposed to explain the clinical presentation. An anterior left thoracotomy with ligation of the abnormal branch and atypical resection of the lung segment comprising the sequestration was performed.


Assuntos
Síndrome Coronariana Aguda/etiologia , Sequestro Broncopulmonar/cirurgia , Anomalias dos Vasos Coronários/cirurgia , Pulmão/irrigação sanguínea , Idoso , Sequestro Broncopulmonar/complicações , Sequestro Broncopulmonar/diagnóstico , Anomalias dos Vasos Coronários/complicações , Anomalias dos Vasos Coronários/diagnóstico , Humanos , Masculino , Toracotomia
10.
Stem Cell Res Ther ; 10(1): 248, 2019 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-31399129

RESUMO

BACKGROUND: Mesenchymal stem/stromal cells (MSCs) are considered an important candidate in cell therapy and tissue engineering approaches. The culture of stem cells in a 3D environment is known to better resemble the in vivo situation and to promote therapeutically relevant effects in isolated cells. Therefore, the aim of this study was to develop an approach for the direct isolation of MSCs from adipose tissue into a 3D environment, avoiding contact to a 2D plastic surface. Furthermore, the use of a cryoprotective medium for the cryopreservation of whole adipose tissue was evaluated. MATERIALS AND METHODS: Cryopreservation of fresh adipose tissue with and without a cryoprotective medium was compared with regard to the viability and metabolic activity of cells. After thawing, the tissue was embedded in a novel human platelet lysate-based hydrogel for the isolation of MSCs. The migration, yield, viability, and metabolic activity of cells from the 3D matrix were compared to cells from 2D explant culture. Also, the surface marker profile and differentiation capacity of MSCs from the 3D matrix were evaluated and compared to MSCs from isolation by enzymatic treatment or 2D explant culture. RESULTS: The cryopreservation of whole adipose tissue was found to be feasible, and therefore, adipose tissue can be stored and is available for MSC isolation on demand. Also, we demonstrate the isolation of MSCs from adipose tissue into the 3D matrix. The cells derived from this isolation procedure display a similar phenotype and differentiation capacity like MSCs derived by traditional procedures. CONCLUSIONS: The presented approach allows to cryopreserve adipose tissue. Furthermore, for the first time, MSCs were directly isolated from the tissue into a soft 3D hydrogel environment, avoiding any contact to a 2D plastic culture surface.


Assuntos
Tecido Adiposo/metabolismo , Plaquetas/metabolismo , Técnicas de Cultura de Células/métodos , Células-Tronco Mesenquimais/citologia , Adulto , Plaquetas/química , Diferenciação Celular , Movimento Celular , Sobrevivência Celular , Criopreservação , Feminino , Humanos , Hidrogéis/química , Células-Tronco Mesenquimais/metabolismo , Pessoa de Meia-Idade , Fenótipo
12.
Coimbra; s.n; nov. 2017. 101 p. tab.
Tese em Português | BDENF - Enfermagem | ID: biblio-1416007

RESUMO

Na prestação de cuidados, os enfermeiros confrontam-se diariamente com barreiras à mobilização dos conhecimentos no procedimento de cateterismo venoso periférico (cvp), tornando-se crucial a formação dos mesmos. Nas metodologias ativas encontrase o debriefing que, de forma estruturada, conduz os formandos na reflexão sobre a ação, consolidando saberes e modificando comportamentos menos adequados. A pertinência da investigação passa por identificar o impacto da aplicação do debriefing na perceção dos enfermeiros sobre o cumprimento das recomendações no procedimento de cateterismo venoso periférico. Trata-se de um estudo quase experimental, antes e após com grupo único, de natureza quantitativa. A colheita de dados realizou-se de janeiro a abril de 2017, em três serviços de urgência de um Centro Hospitalar da região oeste de Portugal. A população-alvo abrangeu 48 enfermeiros aos quais foi solicitado o preenchimento de um questionário relativo às guidelines seguido de uma observação não participante durante o procedimento de cvp, antes e após a realização do debriefing. Os dados foram analisados a partir do SPSS® - Statistical Package for Social Sciences. Com a análise dos resultados constatou-se que os enfermeiros atribuíram importância ao debriefing para o cumprimento das guidelines no procedimento de cvp. Nomeadamente no que respeita ao primeiro momento de higienização das mãos e na instrução do utente ao longo do procedimento. Através da aplicação dos questionários identificaram-se fatores que contribuem para a não adequação das práticas ao recomendado: falta de tempo, de recursos materiais; desconhecimento ou mesmo por opção própria dos profissionais. Constatou-se uma boa consistência interna da Escala de Debriefing no contexto da prática clínica (Alpha de 0,898). Os resultados estão repletos de significado não só para a enfermagem mas também para os enfermeiros, para os serviços e para a instituição. Principalmente no que concerne às questões de gestão de cuidados, de estratégias formativas, e de recursos humanos e materiais. Só assim, é possível a prestação de cuidados com qualidade e em segurança, minimizando os custos associadas aos mesmos. Considera-se necessária a realização de mais estudos para capacitar e aumentar a literacia dos enfermeiros nesta área.


Assuntos
Cateterismo Periférico , Enfermagem , Relatório Técnico , Enfermagem Médico-Cirúrgica
14.
Biosci. j. (Online) ; 33(1): 41-51, jan./feb. 2017. tab, ilus
Artigo em Inglês | LILACS | ID: biblio-965866

RESUMO

The aim of this work was to develop an in vitro conservation protocol for Lippia alba that involved mineral oil and to study the leaf anatomy of L. alba genotypes in in vitro and ex vitro environments. In vitro conservation involved five genotypes; LA-13 and LA-57 (carvone chemotype); LA-22 (linalool chemotype); and LA-29 and LA-44 (citral chemotype). Each genotype was treated with mineral oil, with water, and a control at 18°C and 23°C. Survival (%), shoot height (cm) and leaf color were assessed at 180 and 270 days. The genotypes with the best in vitro conservation outcomes (LA-13 and LA-57) were used to study the anatomy of the leaves. Midrib thickness, leaf blade thickness, adaxial and abaxial cuticles and the number of glandular and tector trichomes were assessed. A temperature of 18°C was optimal for the conservation of genotypes of the carvone chemotypes. The explants were short and had green leaves. This was especially true for LA-57, whose height did not exceed 2.0 cm. At 270 days, the LA-13 and LA-57 genotypes continued to have green and viable leaves, especially LA-57, which had the lowest mean height. Field plants of the carvone chemotype had thicker midribs, leaf blades, and cuticles and had more trichomes. The LA-57 genotype had the most glandular and tector trichomes.


O objetivo deste estudo foi desenvolver um protocolo de conservação in vitro com óleo mineral e estudar a anatomia foliar de genótipos de L. alba nos ambientes in vitro e ex vitro. A conservação in vitro constou de cinco genótipos LA-13 e LA-57 (quimiotipo carvona); LA-22 (quimiotipo linalol); LA-29 e LA-44 (quimiotipo citral), três tratamentos (com óleo mineral, com água e controle) e duas temperaturas 18 e 23°C. Aos 180 e 270 dias, avaliou-se a sobrevivência (%), altura da parte aérea (cm) e coloração das folhas. Os genótipos com os melhores resultados da conservação in vitro (LA-13 e LA-57) foram utilizados para estudos de anatomia. Avaliou-se espessura da nervura central, espessura do limbo foliar, cutículas adaxial e abaxial e quantidade de tricomas glandulares e tectores. A temperatura a 18°C foi a ideal para a conservação dos genótipos do quimiotipo carvona, com folhas verdes e baixos valores para altura, destacando-se LA-57 cuja altura não ultrapassou 2,0 cm. Aos 270 dias LA-13 e LA-57 permaneceram com folhas verdes e viáveis, com destaque para LA-57 com menores médias de altura. A anatomia do quimiotipo carvona mostrou que as plantas de campo apresentaram maiores espessuras da nervura, limbo e cutículas, e maiores quantidades de tricomas. O genótipo LA-57 obteve a maior quantidade de tricomas glandulares e tectores.


Assuntos
Técnicas In Vitro , Óleos Voláteis , Verbenaceae , Lippia/anatomia & histologia
15.
Nutr Hosp ; 33(Suppl 3): 314, 2016 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-27491579

RESUMO

INTRODUCTION: The importance of hydration is undoubtable but reliable data on hydration status and its relation with diet is lacking. OBJECTIVES: We aimed to evaluate the hydration status and its relation to beverages and food intake in children. METHODS: A sample of 172 (50% male), 7-11 year-old children was included in this survey. Participants completed a 24 h urine collection; a 24 hours food recall corresponding to the day of urine collection was applied, weight and height were measured and parents/caregivers fi lled a lifestyle and socio-demographic questionnaire. The free water reserve was used to assess the hydration status. The intakes of food and beverages were compared according to hydration status using the t-test, Mann-Whitney test or unconditional regression models as appropriate. RESULTS: More than half of the participants were classifi ed as hypohydrated or at risk of hypohydration (57% in girls and 58% in boys). Compared to hypohydrated children, a signifi cant higher consumption of water (276.2 ± 208.4 vs 188.2 ± 187.4 g/day) and fruit juices (77.6 ± 139.4 vs 14.4 ± 57.2 g/day) was reported by euhydrated boys and girls, respectively. Lower consumers of water and fruit juices showed a higher risk of hypohydration (OR = 2.16, 95% CI: 1.02-4.58, p = 0.045), adjusting for confounders. CONCLUSIONS: Most of the children included in this analysis were classifi ed as at risk of hypohydration and those with higher water and fruit juices consumption showed a better hydration status.


Assuntos
Biomarcadores/urina , Água Corporal/fisiologia , Ingestão de Líquidos/fisiologia , Bebidas , Criança , Estudos Transversais , Dieta , Feminino , Frutas , Humanos , Masculino , Inquéritos Nutricionais , Portugal/epidemiologia , Fatores Socioeconômicos
17.
Nutr. hosp ; 33(supl.3): 35-40, 2016. tab
Artigo em Inglês | IBECS | ID: ibc-154660

RESUMO

Introduction: The importance of hydration is undoubtable but reliable data on hydration status and its relation with diet is lacking. Objectives: We aimed to evaluate the hydration status and its relation to beverages and food intake in children. Methods: A sample of 172 (50% male), 7-11 year-old children was included in this survey. Participants completed a 24 h urine collection; a 24 hours food recall corresponding to the day of urine collection was applied, weight and height were measured and parents/caregivers filled a lifestyle and socio-demographic questionnaire. The free water reserve was used to assess the hydration status. The intakes of food and beverages were compared according to hydration status using the t-test, Mann-Whitney test or unconditional regression models as appropriate. Results: More than half of the participants were classified as hypohydrated or at risk of hypohydration (57% in girls and 58% in boys). Compared to hypohydrated children, a significant higher consumption of water (276.2 ± 208.4 vs 188.2 ± 187.4 g/day) and fruit juices (77.6 ± 139.4 vs 14.4 ± 57.2 g/day) was reported by euhydrated boys and girls, respectively. Lower consumers of water and fruit juices showed a higher risk of hypohydration (OR = 2.16, 95% CI: 1.02-4.58, p = 0.045), adjusting for confounders. Conclusions: Most of the children included in this analysis were classified as at risk of hypohydration and those with higher water and fruit juices consumption showed a better hydration status (AU)


No disponible


Assuntos
Humanos , Masculino , Feminino , Criança , Comportamento Alimentar , Avaliação Nutricional , Obesidade Infantil/epidemiologia , Sobrepeso/epidemiologia , Equilíbrio Hidroeletrolítico/fisiologia , Urinálise/estatística & dados numéricos , Biomarcadores/análise , Água Corporal/fisiologia , Estudos Transversais
18.
BMC Pediatr ; 15: 60, 2015 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-25982707

RESUMO

BACKGROUND: Data from studies assessing the intake of potassium, and the concomitant sodium-to-potassium ratio are limited. The aim of this study was to evaluate potassium and sodium-to-potassium ratio intake in 8-10 year-old children. METHODS: A cross-sectional survey was carried out from January to June 2014 and data from 163 children (81 boys) were included. Potassium intake was estimated by 24-h urine collection and coefficient of creatinine was used to validate completeness of urine collections. Urinary sodium and sodium-to-potassium ratio were also analysed. A 24-h dietary recall was used to provide information on dietary sources of potassium. Height and weight were measured according to international standards. RESULTS: The mean urinary potassium excretion was 1701 ± 594 mg/day in boys, and 1682 ± 541 mg/day in girls (p = 0.835); 8.0% of children met the WHO recommendations for potassium intake. The mean sodium excretion was 2935 ± 1075 mg/day in boys and 2381 ± 1045 mg/day in girls (p <0.001) and urinary sodium-to-potassium ratio was 3.2 ± 1.4 in boys, and 2.5 ± 1.1 in girls (p = 0.002). The mean fruit and vegetable intake was 353.1 ± 232.5 g/day in boys, and 290.8 ± 213.1 g/day in girls (p = 0.101). CONCLUSIONS: This study reported a low compliance of potassium intake recommendations in 8-10 year-old children. Health promotion interventions are needed in order to broaden public awareness of potassium inadequacy and to increase potassium intake.


Assuntos
Comportamento Alimentar , Potássio/urina , Índice de Massa Corporal , Criança , Creatinina/urina , Estudos Transversais , Escolaridade , Ingestão de Energia , Feminino , Frutas , Humanos , Masculino , Atividade Motora , Pais , Portugal , Sódio/urina , Sódio na Dieta , Inquéritos e Questionários , Verduras
19.
Biosci. j. (Online) ; 29(3): 617-622, may/june 2013.
Artigo em Português | LILACS | ID: biblio-914594

RESUMO

Objetivou-se desenvolver uma metodologia para possibilitar a classificação de plantas de bananeira submetidas à indução de duplicação cromossômica utilizando Redes Neurais Artificiais (RNA). Os dados utilizados neste trabalho foram retirados de uma tese já apresentada, cujo autor estudou a correlação entre a massa fresca de discos foliares e o conteúdo de DNA. A RNA foi implementada com a função de classificação. A taxa de aprendizado e o termo momentum adotados foram respectivamente iguais a 0,01 e 0,2, o número de épocas de treinamento foi 1000. Esses valores foram determinados por meio de tentativa e erro. Para o treinamento, 90% das plantas foram utilizadas e, para validação, 10% do total de 114 autotetraploides produzidos artificialmente por meio de exposição ao antimitódico colchicina. A RNA classificou corretamente 10 das 11 amostras utilizadas para validação. A estatística Kappa foi de 63,33%, o que indica que a RNA pode ainda ser melhorada. A rede neural artificial do tipo Multi Layer Perceptron implementada é eficaz na préseleção de poliploides desejáveis de bananeira Tong Dok Mak.


The objective was to develop a methodology to enable the classification of banana crop subjected to induction of chromosome doubling using Neural Networks (NN). The data used in this study were taken from a thesis already presented, whose authors studied the correlation between fresh weight of leaf discs and DNA content. The NN was implemented by the ranking function. The learning rate and momentum term used were respectively equal to 0.01 and 0.2, the number of training epochs was 1000. These values were determined by trial and error. For training, 90% of the plants were employed, and for validation, 10% of the total of 114 autotetraploids artificially produced by exposure to antimitodic agent colchicine. The NN correctly classified 10 of the 11 samples used for validation. Kappa statistics was 63.33%, which indicates that the NN can be further improved. The artificial neural network-type Multi Layer Perceptron is effectively implemented in the pre-selection of polyploid desirable banana Tong Dok Mak.


Assuntos
Redes Neurais de Computação , Musa , Colchicina , Duplicação Cromossômica
20.
Hemoglobin ; 36(6): 517-25, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23181747

RESUMO

We report a new structural defect of the α2-globin chain presenting with moderate microcytic hypochromic anemia, in six individuals from three unrelated families, living in Portugal and Spain. α-Globin gene deletions were ruled out by gap-polymerase chain reaction (gap-PCR) and multiplex ligation-dependent probe amplification (MLPA). Direct sequencing of the α2-globin gene revealed a substitution of codon 104 [α104(G11)Cys→Arg, TGC>CGC (α2) (HBA2:c.313T>C)]. This new variant, not detectable by high performance liquid chromatography (HPLC) or electrophoresis, was called Hb Iberia, as it was observed for the first time in families from the Iberian Peninsula. Although the mutant allele is transcribed, as indicated by the balanced mRNA α/ß ratio, the abnormal α2 chain could not form a stable tetramer as the cysteine and arginine residues, located at the α1ß1 contact, differ in size, charge and hydrophobicity. Hb Iberia is the third mutation described at codon 104 on the α-globin genes, namely, Hb Sallanches (α2, TGC>TAC) and Hb Oegstgeest (α1, TGC>AGC), also characterized as unstable hemoglobins (Hbs), present on an α-thalassemic phenotype.


Assuntos
Hemoglobinas Anormais/genética , alfa-Globinas/genética , Talassemia alfa/genética , Adulto , Idoso , Substituição de Aminoácidos , Sequência de Bases , Códon , Éxons , Feminino , Genótipo , Hemoglobinas Anormais/química , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Moleculares , Mutação Puntual , Portugal , Conformação Proteica , Espanha , Adulto Jovem , alfa-Globinas/química , Talassemia alfa/diagnóstico
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