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1.
Chaos ; 29(10): 103124, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31675835

RESUMO

Oscillons are time-dependent, localized in space, extremely long-lived states in nonlinear scalar-field models, while kinks are topological solitons in one spatial dimension. In the present work, we show new classes of oscillons and oscillating kinks in a system of two nonlinearly coupled scalar fields in 1+1 spatiotemporal dimensions. The solutions contain a control parameter, the variation of which produces oscillons and kinks with a flat-top shape. The model finds applications in condensed matter, cosmology, and high-energy physics.

2.
Cytogenet Genome Res ; 139(4): 284-8, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23548553

RESUMO

Small supernumerary marker chromosomes (sSMC) are structurally abnormal chromosomes, generally equal in size or smaller than a chromosome 20 of the same metaphase spread. Most of them are unexpectedly detected in routine karyotype analyses, and it is usually not easy to correlate them with a specific clinical picture. A small group of sSMCs is derived from more than one chromosome, called complex sSMCs. Here, we report on a patient with a de novo complex sSMC, derived from chromosomes 8 and 14. Banding karyotype analysis, multiplex ligation-dependent probe amplification (MLPA), single nucleotide polymorphism (SNP)-based array, and fluorescence in situ hybridization (FISH) were performed to investigate its origin. Array and FISH analyses revealed a der(14)t(8;14)(p23.2;q22.1)dn. The propositus presents some clinical features commonly found in patients with partial duplication or triplication of 8p and 14q. This is the first report describing a patient with a congenital der(14)t(8;14)(p23.2;q22.1)dn sSMC.


Assuntos
Transtornos Cromossômicos/genética , Cromossomos Humanos Par 14/genética , Cromossomos Humanos Par 8/genética , Anormalidades Múltiplas/genética , Pré-Escolar , Bandeamento Cromossômico , Transtornos Cromossômicos/patologia , Fatores de Transcrição Forkhead/genética , Humanos , Hibridização in Situ Fluorescente , Lactente , Recém-Nascido , Masculino , Reação em Cadeia da Polimerase Multiplex , Proteínas do Tecido Nervoso/genética , Fenótipo , Polimorfismo de Nucleotídeo Único
3.
Cytogenet Genome Res ; 138(1): 5-10, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22890013

RESUMO

A small supernumerary marker chromosome (sSMC) derived from chromosome 22 is a relatively common cytogenetic finding. This sSMC typically results in tetrasomy for a chromosomal region that spans the chromosome 22p arm and the proximal 2 Mb of 22q11.21. Using classical cytogenetics, fluorescence in situ hybridization, multiplex ligation-dependent probe amplification, and array techniques, 7 patients with sSMCs derived from chromosome 22 were studied: 4 non-related and 3 from the same family (mother, daughter, and son). The sSMCs in all patients were dicentric and bisatellited chromosomes with breakpoints in the chromosome 22 low-copy repeat A region, resulting in cat eye syndrome (CES) due to chromosome 22 partial tetrasomy 22pter→q11.2 including the cat eye chromosome region. Although all subjects presented the same chromosomal abnormality, they showed a wide range of phenotypic differences, even in the 3 patients from the same family. There are no previous reports of CES occurring within 3 patients in the same family. Thus, the clinical and follow-up data presented here contribute to a better delineation of the phenotypes and outcomes of CES patients and will be useful for genetic counseling.


Assuntos
Transtornos Cromossômicos/genética , Adulto , Aneuploidia , Criança , Pré-Escolar , Cromossomos Humanos Par 22/genética , Epigênese Genética , Anormalidades do Olho , Feminino , Seguimentos , Dosagem de Genes , Predisposição Genética para Doença , Humanos , Lactente , Masculino , Adulto Jovem
4.
Cytogenet Genome Res ; 138(1): 1-4, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22796746

RESUMO

The presence of a supernumerary 18p isochromosome is a rare chromosomal abnormality that results in 18p tetrasomy. This is a report on the clinical, cytogenetic and molecular findings of 2 non-related patients with a supernumerary 18p isochromosome. Both patients present some features of the 18p tetrasomy syndrome (strabismus, low-set ears, long and narrow fingers and toes), but additional characteristics were also observed. Cytogenetic analysis, FISH, MLPA and SNP array techniques showed that one of the isochromosomes is symmetric and monocentric, while the other is asymmetric and dicentric, yet resulting in a similar tetrasomy of the 18pter-18p10 region, followed by a partial 18q11.2 trisomy, an unprecedented finding in the literature.


Assuntos
Isocromossomos , Trissomia/genética , Criança , Cromossomos Humanos Par 18/genética , Análise Citogenética , Epigênese Genética , Feminino , Humanos , Lactente
5.
Parasite Immunol ; 34(10): 492-8, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22817661

RESUMO

CBA mouse macrophages effectively control Leishmania major infection, yet are permissive to Leishmania amazonensis. It has been established that some Leishmania species are destroyed by reactive oxygen species (ROS). However, other species of Leishmania exhibit resistance to ROS or even down-modulate ROS production. We hypothesized that L. amazonensis-infected macrophages reduce ROS production soon after parasite-cell interaction. Employing a highly sensitive analysis technique based on chemiluminescence, the production of superoxide (O(·-)(2)) and hydrogen peroxide (H(2)O(2)) by L. major- or L. amazonensis-infected CBA macrophages were measured. L. major induces macrophages to release levels of (O(·-)(2)) 3·5 times higher than in uninfected cells. This (O(·-)(2)) production is partially dependent on NADPH oxidase (NOX) type 2. The level of accumulated H(2)O(2) is 20 times higher in L. major-than in L. amazonensis-infected cells. Furthermore, macrophages stimulated with L. amazonensis release amounts of ROS similar to uninfected cells. These findings support previous studies showing that CBA macrophages are effective in controlling L. major infection by a mechanism dependent on both (O(·-)(2)) production and H(2)O(2) generation. Furthermore, these data reinforce the notion that L. amazonensis survive inside CBA macrophages by reducing ROS production during the phagocytic process.


Assuntos
Leishmania mexicana/imunologia , Macrófagos/imunologia , Macrófagos/parasitologia , Espécies Reativas de Oxigênio/metabolismo , Animais , Peróxido de Hidrogênio/análise , Leishmania/imunologia , Leishmania major/imunologia , Medições Luminescentes , Camundongos , Camundongos Endogâmicos CBA , NADPH Oxidases/metabolismo , Superóxidos/análise
6.
J Clin Pediatr Dent ; 37(1): 5-8, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23342559

RESUMO

Autogenous tooth fragment bonding offers advantages over restorations with composite resins and porcelain, including better esthetics, greater durability, reestablishment of the natural function of the dental element and short execution time. A case is presented of a 14-year-old male patient who suffered an oblique crown fracture of the permanent right maxillary central incisor (11) due to a traumatic fall. The clinical examination revealed pulp exposure with no invasion of the biological space. Due to the extension of the fracture, endodontic treatment and the placement of an intra-root esthetic pin was needed. The tooth was restored using the autogenous fragment bonding method. Excellent esthetic and functional results were observed after two years of follow up.


Assuntos
Colagem Dentária , Planejamento de Prótese Dentária , Estética Dentária , Incisivo/lesões , Técnica para Retentor Intrarradicular , Sorriso , Coroa do Dente/lesões , Fraturas dos Dentes/terapia , Condicionamento Ácido do Dente/métodos , Adolescente , Resinas Compostas/química , Materiais Dentários/química , Adesivos Dentinários/química , Seguimentos , Vidro/química , Humanos , Masculino , Metacrilatos/química , Tratamento do Canal Radicular/métodos , Dióxido de Silício/química , Zircônio/química
7.
Braz J Biol ; 81(4): 867-871, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33053119

RESUMO

Chagas disease (CD) is considered a typical low-income population sickness of the developing countries in Latin America. Given the historical relevance of CD in individuals in southern Rio Grande do Sul (RS) State, Brazil, the aim of this study was to identify the knowledge of the CD and its vectors by cardiac patients, and the prevalence of anti-T cruzi antibodies in these individuals in Pelotas, city located in Rio Grande do Sul (RS) state, Brazil. The subjects with cardiac disease were submitted to a semi-structured questionnaire as well as two serological tests in order to detect anti-T. cruzi IgG antibodies. Of the individuals that born in municipalities showing the highest triatomine infestation rates in recent decades, 81.8% were able to recognize the vector insect (p = 0.0042; OR = 5.9), and 83.3% reported either themselves or someone in their families to have CD (p = 0.043, OR = 5.2). Of the 54 patients submitted to serological analysis, only 01 patient (1.9%) was positive for anti-T. cruzi antibodies, a 55 year old man from the rural area of Canguçu county. This study provides support for the evaluation to be extended to other cardiology centers, given the importance of Chagas disease in Brazil.


Assuntos
Doença de Chagas , Trypanosoma cruzi , Animais , Brasil/epidemiologia , Doença de Chagas/epidemiologia , Humanos , Insetos Vetores , Masculino , Pessoa de Meia-Idade , Estudos Soroepidemiológicos
8.
Cytogenet Genome Res ; 128(1-3): 105-10, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20407220

RESUMO

Normal diploid somatic mammalian cell division generates 2 daughter cells as a result of a strict and well-controlled mitotic process. However, some defects during the progression of that process could generate an unbalanced distribution of chromosomes, aneuploidy and eventually, a malignant phenotype. Previous observations using a transgenic mouse model with diminished DNA repair capacity revealed the presence of nuclear buds (NBs) induced in vitro by the nucleoside analog zidovudine (Retrovir(R), 3'-azido-3'-deoxythymidine, AZT). Here we used bone marrow mesenchymal cells, taken from mice with the Xpa(-/-)Trp53(+/-) genotype, that were cultured and exposed to 0 and 100 muM AZT for 24 hours. Fixed and denatured cells were processed by fluorescence in situ hybridization (FISH) with whole chromosome painting probes used to identify chromosomes in cells growing on glass chamber slides (2 probes/slide). A variety of sizes and shapes of NBs were observed. Some NBs had a large connection with the main nucleus (>(1/4) of the NB diameter), others hada smaller connection (<(1/4) of the NB diameter), some were circular and positioned close to the nucleus, while some resided in the cytoplasm separated from the nucleus or connected by a thin chromatin strand. We had hypothesized that NBs would progress in the process of budding until separation occurred, but this was not proven by time-lapse photography studies performed for 20 hours. From 1,126 cells scored in the unexposed cultures, 10.39 % of cells carried NBs, while from 1,108 cells scored in the AZT-exposed cultures 29.16% of cells carried NBs (p = 0.001). In AZT-exposed cells there were a total of 322 NBs scored; 46.6% or 150 NBs contained positive signals for one or both probes used, while 53% or 172 NBs had no probe signal. In addition, FISH analysis showed no preferential localization of any chromosome within the NBs. Among the NBs that carried no probe signal, the presence of positive signals with inversion of DAPI imaging demonstrated centromeric content. It has been hypothesized that NBs occur as a result of expulsion of amplified DNA from the main nucleus; however, this data demonstrates that NBs may contain any chromosome, suggesting that NBs do not consist of just amplified DNA.


Assuntos
Fármacos Anti-HIV/toxicidade , Núcleo Celular/efeitos dos fármacos , Zidovudina/toxicidade , Animais , Camundongos , Proteína Supressora de Tumor p53/genética , Proteína de Xeroderma Pigmentoso Grupo A/genética
9.
Science ; 276(5321): 2045-7, 1997 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-9197268

RESUMO

Parkinson's disease (PD) is a common neurodegenerative disorder with a lifetime incidence of approximately 2 percent. A pattern of familial aggregation has been documented for the disorder, and it was recently reported that a PD susceptibility gene in a large Italian kindred is located on the long arm of human chromosome 4. A mutation was identified in the alpha-synuclein gene, which codes for a presynaptic protein thought to be involved in neuronal plasticity, in the Italian kindred and in three unrelated families of Greek origin with autosomal dominant inheritance for the PD phenotype. This finding of a specific molecular alteration associated with PD will facilitate the detailed understanding of the pathophysiology of the disorder.


Assuntos
Proteínas do Tecido Nervoso/genética , Doença de Parkinson/genética , Mutação Puntual , Idade de Início , Sequência de Aminoácidos , Animais , Sequência de Bases , Mapeamento Cromossômico , Cromossomos Humanos Par 4 , Feminino , Genes Dominantes , Marcadores Genéticos , Grécia , Humanos , Itália , Masculino , Dados de Sequência Molecular , Proteínas do Tecido Nervoso/química , Proteínas do Tecido Nervoso/fisiologia , Linhagem , Fenótipo , Reação em Cadeia da Polimerase , Estrutura Secundária de Proteína , Sinucleínas , alfa-Sinucleína
10.
Peptides ; 29(9): 1505-13, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18554751

RESUMO

Here, we described the expression and characterization of the recombinant toxin LTx2, which was previously isolated from the venomous cDNA library of a Brazilian spider, Lasiodora sp. (Mygalomorphae, Theraphosidae). The recombinant toxin found in the soluble and insoluble fractions was purified by reverse phase high-performance liquid chromatography (HPLC). Ca2+ imaging analysis revealed that the recombinant LTx2 acts on calcium channels of BC3H1 cells, blocking L-type calcium channels.


Assuntos
Neurotoxinas/biossíntese , Neurotoxinas/farmacologia , Venenos de Aranha/química , Venenos de Aranha/farmacologia , Animais , Cálcio/fisiologia , Canais de Cálcio/efeitos dos fármacos , Canais de Cálcio/fisiologia , Linhagem Celular , Clonagem Molecular , Receptores de Inositol 1,4,5-Trifosfato/biossíntese , Camundongos , Proteínas Recombinantes/química , Proteínas Recombinantes/isolamento & purificação , Canal de Liberação de Cálcio do Receptor de Rianodina/biossíntese , Venenos de Aranha/biossíntese , Aranhas/química
11.
J Hazard Mater ; 152(2): 648-55, 2008 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-17728063

RESUMO

Copper-cyanide bleed streams arise from contaminated baths from industrial electroplating processes due to the buildup of impurities during continuous operation. These streams present an elevated concentration of carbonate, cyanide and copper, constituting a heavy hazard, which has to be treated for cyanide destruction and heavy metals removal, according to the local environmental laws. In the Brazilian Mint, bleed streams are treated with sodium hypochlorite, to destroy cyanide and precipitate copper hydroxide, a solid hazardous waste that has to be disposed properly in a landfill or treated for metal recovery. In this paper, a laboratory-scale electrolytic cell was developed to remove the copper from the bleed stream of the electroplating unit of the Brazilian Mint, permitting its reutilization in the plant and decreasing the amount of sludge to waste. Under favorable conditions copper recoveries around 99.9% were achieved, with an energy consumption of about 11 kWh/kg, after a 5-h electrolysis of a bath containing copper and total cyanide concentrations of 26 and 27 g/L, respectively. Additionally, a substantial reduction of the cyanide concentration was also achieved, decreasing the pollution load and final treatment costs.


Assuntos
Cobre/isolamento & purificação , Cianetos/isolamento & purificação , Galvanoplastia , Resíduos Industriais , Poluentes Químicos da Água/isolamento & purificação , Eletrólise , Oxirredução
14.
BMC Med Genet ; 8: 76, 2007 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-18070351

RESUMO

BACKGROUND: Ischemic stroke is the most common cause of disability in North America and in addition to the generally accepted risk factors, there is increasing evidence for the potential pathophysiological role of genes. One of these genes, the endothelial nitric oxide synthase gene (NOS3) has been reported as a genetic risk factor for ischemic stroke. To independently confirm and extend the results of these previous reports, we investigated this gene as a risk factor for stroke in an ethnically diverse study population. METHODS: Using the TOAST classification, we characterized and studied 377 patients with ischemic stroke. We genotyped two common variants in the NOS3 gene, the intron 4 insertion/deletion and an exonic single nucleotide polymorphism (SNP), G894T, in these patients and compared them with 502 controls. Chi-square or Fisher's exact tests were used to examine allele effects on stroke and stroke subtypes. Logistic regression analysis was used to adjust for confounding covariate effects. RESULTS: All genotypes are in Hardy-Weinberg equilibrium except for intron 4c, which is overrepresented in ischemic stroke patients. In pooled analysis of all patients, intron 4c, but not intron 4a, intron 4b or G894T alleles are associated with stroke (p < 0.01). In subgroup analysis by race, the intron 4c allele is most strongly associated with large artery ischemic stroke in African Americans (p < 0.01). CONCLUSION: We are unable to confirm previous reports of an association of the intron 4a or the G894T alleles with ischemic stroke. However, although limited by a relatively small sample size, our study suggests a potentially important role of the intron 4c allele as a genetic marker of ischemic stroke in African Americans.


Assuntos
Negro ou Afro-Americano , Isquemia Encefálica/genética , Predisposição Genética para Doença , Óxido Nítrico Sintase Tipo III/genética , Acidente Vascular Cerebral/genética , Idoso , Idoso de 80 Anos ou mais , Alelos , Isquemia Encefálica/etnologia , Feminino , Frequência do Gene , Marcadores Genéticos , Genótipo , Humanos , Íntrons , Masculino , Pessoa de Meia-Idade , Razão de Chances , Polimorfismo de Nucleotídeo Único , Acidente Vascular Cerebral/etnologia
15.
Neotrop Entomol ; 46(2): 231-234, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27785704

RESUMO

We present a simple technique for keeping the form of artificially expanded endophalli in bees (Hymenoptera). Endophalli were inflated using the introduction of low melting-point agarose from a syringe inserted in the anterior opening of the metasoma. Under refrigeration, the endophalli kept their expanded shape for up to three days allowing the description of structure, morphometric analyses, and examination of the external sculpturing of the cuticle under scanning electron microscope. The technique provides new possibilities for the study of functional morphology, sexual selection, and reconstruction of bee phylogeny.


Assuntos
Abelhas , Microscopia Eletrônica de Varredura , Manejo de Espécimes , Animais , Himenópteros , Filogenia
16.
Braz J Med Biol Res ; 39(3): 355-63, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16501815

RESUMO

Glutathione is the major intracellular antioxidant thiol protecting mammalian cells against oxidative stress induced by oxygen- and nitrogen-derived reactive species. In trypanosomes and leishmanias, trypanothione plays a central role in parasite protection against mammalian host defence systems by recycling trypanothione disulphide by the enzyme trypanothione reductase. Although Kinetoplastida parasites lack glutathione reductase, they maintain significant levels of glutathione. The aim of this study was to use Leishmania donovani trypanothione reductase gene mutant clones and different Leishmania species to examine the role of these two individual thiol systems in the protection mechanism against S-nitroso-N-acetyl-D,L-penicillamine (SNAP), a nitrogen-derived reactive species donor. We found that the resistance to SNAP of different species of Leishmania was inversely correlated with their glutathione concentration but not with their total low-molecular weight thiol content (about 0.18 nmol/10(7) parasites, regardless Leishmania species). The glutathione concentration in L. amazonensis, L. donovani, L. major, and L. braziliensis were 0.12, 0.10, 0.08, and 0.04 nmol/10(7) parasites, respectively. L. amazonensis, that have a higher level of glutathione, were less susceptible to SNAP (30 and 100 microM). The IC50 values of SNAP determined to L. amazonensis, L. donovani, L. major, and L. braziliensis were 207.8, 188.5, 160.9, and 83 microM, respectively. We also observed that L. donovani mutants carrying only one trypanothione reductase allele had a decreased capacity to survive (approximately 40%) in the presence of SNAP (30-150 microM). In conclusion, the present data suggest that both antioxidant systems, glutathione and trypanothione/trypanothione reductase, participate in protection of Leishmania against the toxic effect of nitrogen-derived reactive species.


Assuntos
Glutationa/metabolismo , Leishmania/efeitos dos fármacos , NADH NADPH Oxirredutases/metabolismo , Penicilamina/análogos & derivados , Animais , Fluoresceínas , Leishmania/enzimologia , Peso Molecular , NADH NADPH Oxirredutases/genética , Ouabaína/análogos & derivados , Penicilamina/toxicidade , Especificidade da Espécie
17.
Braz. j. biol ; 81(4): 867-871, Oct.-Dec. 2021. tab
Artigo em Inglês | LILACS | ID: biblio-1153428

RESUMO

Abstract Chagas disease (CD) is considered a typical low-income population sickness of the developing countries in Latin America. Given the historical relevance of CD in individuals in southern Rio Grande do Sul (RS) State, Brazil, the aim of this study was to identify the knowledge of the CD and its vectors by cardiac patients, and the prevalence of anti-T cruzi antibodies in these individuals in Pelotas, city located in Rio Grande do Sul (RS) state, Brazil. The subjects with cardiac disease were submitted to a semi-structured questionnaire as well as two serological tests in order to detect anti-T. cruzi IgG antibodies. Of the individuals that born in municipalities showing the highest triatomine infestation rates in recent decades, 81.8% were able to recognize the vector insect (p = 0.0042; OR = 5.9), and 83.3% reported either themselves or someone in their families to have CD (p = 0.043, OR = 5.2). Of the 54 patients submitted to serological analysis, only 01 patient (1.9%) was positive for anti-T. cruzi antibodies, a 55 year old man from the rural area of Canguçu county. This study provides support for the evaluation to be extended to other cardiology centers, given the importance of Chagas disease in Brazil.


Resumo A doença de Chagas (DC) é considerada uma doença típica da população de baixa renda dos países em desenvolvimento da América Latina. Dada a relevância histórica da DC em indivíduos do sul do Estado do Rio Grande do Sul (RS), o objetivo deste estudo foi identificar o conhecimento da doença de Chagas (DC) e seus vetores em pacientes cardíacos, e a prevalência de anticorpos anti-T cruzi nesses indivíduos, em Pelotas, cidade localizada no Rio Grande do Sul (RS), Brasil. Os pacientes cardiopatas foram submetidos a um questionário semiestruturado, e também a dois testes sorológicos para detecção de anticorpos anti-T. cruzi IgG. Dos indivíduos que nasceram em municípios com as maiores taxas de infestação por triatomíneos nas últimas décadas, 81,8% foram capazes de reconhecer o inseto vetor (p = 0,0042; OR = 5,9), e 83,3% relataram que eles próprios ou alguém em suas famílias tem DC (p = 0,043, OR = 5,2). Dos 54 pacientes submetidos à análise sorológica, apenas 01 paciente (1,9%) foi positivo para anticorpos anti-T.cruzi, um homem de 55 anos da área rural do município de Canguçu. Este estudo fornece subsídios para que a avaliação seja estendida a outros centros de cardiologia, devido à importância da doença de Chagas no Brasil.


Assuntos
Humanos , Animais , Pessoa de Meia-Idade , Trypanosoma cruzi , Doença de Chagas/epidemiologia , Brasil/epidemiologia , Estudos Soroepidemiológicos , Insetos Vetores
18.
Waste Manag ; 47(Pt A): 149-54, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26159043

RESUMO

This article aims to describe an alternative and innovative methodology to transform waste, frying oil in a potential energy source, the biodiesel. The biodiesel was produced from fatty acids, using a waste product of the food industry as the raw material. The methodology to be described is the corona discharge plasma technology, which offers advantages such as acceleration of the esterification reaction, easy separation of the biodiesel and the elimination of waste generation. The best conditions were found to be an oil/methanol molar ratio of 6:1, ambient temperature (25 °C) and reaction time of 110 min and 30 mL of sample. The acid value indicates the content of free fatty acids in the biodiesel and the value obtained in this study was 0.43 mg KOH/g. Peaks corresponding to octadecadienoic acid methyl ester, octadecanoic acid methyl ester and octadecenoic acid methyl ester, from the biodiesel composition, were identified using GC-MS. A major advantage of this process is that the methyl ester can be obtained in the absence of chemical catalysts and without the formation of the co-product (glycerin).


Assuntos
Biocombustíveis/análise , Ácidos Graxos/química , Indústria Alimentícia , Resíduos Industriais/análise , Gerenciamento de Resíduos/métodos , Cromatografia Gasosa-Espectrometria de Massas , Projetos Piloto , Gases em Plasma/química , Gerenciamento de Resíduos/instrumentação
19.
Genetics ; 159(2): 715-26, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11606546

RESUMO

The major locus for dominant preaxial polydactyly in humans has been mapped to 7q36. In mice the dominant Hemimelic extra toes (Hx) and Hammertoe (Hm) mutations map to a homologous chromosomal region and cause similar limb defects. The Lmbr1 gene is entirely within the small critical intervals recently defined for both the mouse and human mutations and is misexpressed at the exact time that the mouse Hx phenotype becomes apparent during limb development. This result suggests that Lmbr1 may underlie preaxial polydactyly in both mice and humans. We have used deletion chromosomes to demonstrate that the dominant mouse and human limb defects arise from gain-of-function mutations and not from haploinsufficiency. Furthermore, we created a loss-of-function mutation in the mouse Lmbr1 gene that causes digit number reduction (oligodactyly) on its own and in trans to a deletion chromosome. The loss of digits that we observed in mice with reduced Lmbr1 activity is in contrast to the gain of digits observed in Hx mice and human polydactyly patients. Our results suggest that the Lmbr1 gene is required for limb formation and that reciprocal changes in levels of Lmbr1 activity can lead to either increases or decreases in the number of digits in the vertebrate limb.


Assuntos
Deformidades Congênitas dos Membros/genética , Proteínas de Membrana/genética , Mutação , Alelos , Animais , Northern Blotting , Mapeamento Cromossômico , Cromossomos Artificiais Bacterianos , Cromossomos Humanos Par 7 , Homozigoto , Humanos , Hibridização in Situ Fluorescente , Camundongos , Fenótipo
20.
Tissue Eng ; 11(1-2): 172-81, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15738672

RESUMO

Therapeutic irradiation for head and neck cancer, and the autoimmune disease Sjogren's syndrome, lead to loss of salivary parenchyma. They are the two main causes of irreversible salivary gland hypofunction. Such patients cannot produce adequate levels of saliva, leading to considerable morbidity. We are working to develop an artificial salivary gland for such patients. A major problem in this endeavor has been the difficulty in obtaining a suitable autologous cellular component. This article describes a method of culturing and expanding primary salivary cells obtained from human submandibular glands (huSMGs) that is serum free and yields cells that are epithelial in nature. These include morphological (light and transmission electron microscopy [TEM]), protein expression (immunologically positive for ZO-1, claudin-1, and E-cadherin), and functional evidence. Under confocal microscopy, huSMG cells show polarization and appropriately localize tight junction proteins. TEM micrographs show an absence of dense core granules, but confirm the presence of tight and intermediate junctions and desmosomes between the cells. Functional assays showed that huSMG cells have high transepithelial electrical resistance and low rates of paracellular fluid movement. Additionally, huSMG cells show a normal karyotype without any morphological or numerical abnormalities, and most closely resemble striated and excretory duct cells in appearance. We conclude that this culture method for obtaining autologous human salivary cells should be useful in developing an artificial salivary gland.


Assuntos
Órgãos Artificiais , Técnicas de Cultura de Células/métodos , Polaridade Celular , Células Epiteliais/citologia , Glândulas Salivares/citologia , Engenharia Tecidual/métodos , Células Cultivadas , Meios de Cultura Livres de Soro , Células Epiteliais/metabolismo , Células Epiteliais/ultraestrutura , Humanos , Glândulas Salivares/metabolismo , Glândula Submandibular/citologia , Glândula Submandibular/metabolismo , Junções Íntimas/metabolismo , Junções Íntimas/ultraestrutura
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