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1.
Cryo Letters ; 44(5): 274-279, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38032307

RESUMO

BACKGROUND: N. wightii (Leguminosae) is valued as a cover crop and as a potential source of protein in food insecure countries. However, plantlet establishment is limited by physical dormancy. Our previous work has shown that exposure of N. wightii seeds to cryogenic temperatures is able to overcome physical dormancy. OBJECTIVE: The current study is an extension of that work where the field performance and nutritional composition of plants regenerated from N. wightii seeds was investigated. RESULTS: It was evident that plants regenerated from cryopreserved seeds displayed faster growth rates than those from control seeds. In addition, cryopreservation did not alter the nutritional profile of plants produced from cryo-stored seeds. CONCLUSION: Collectively, the results indicate that cryopreservation serves as a suitable strategy for the preservation of seeds of N. wightii with the added benefit of also serving as a dormancy breaking mechanism upon retrieval from cryogenic temperatures. Doi.org/10.54680/fr23510110712.


Assuntos
Criopreservação , Fabaceae , Estado Nutricional , Sementes , Temperatura
2.
Waste Manag ; 166: 270-279, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37207588

RESUMO

This work presents a study of synthesis and characterization of catalysts-based cerium and nickel supported on the pumice stone (Ce/Pumice and Ni/Pumice) to be used in the gasification process of an invasive species present in the Canary Islands, such as Pennisetum setaceum to obtain syngas. Specifically, the effect of the metal impregnated on the pumice, and the effect of catalyst on the gasification process was studied. For this purpose, the composition of the gas was determined and the results obtained were compared with those obtained in non-catalytic thermochemical processes. Gasification tests were performed using a simultaneous thermal analyzer coupled with a mass spectrometer, providing a detailed analysis of the gases released during the process. The results showed that during the catalytic gasification process of the Pennisetum setaceum, the gases produced appear at lower temperatures in the catalytic process that in the non-catalytic process. Specifically, H2 appears at 640.42 °C and 641.84 °C when Ce/pumice and Ni/pumice were used as catalyst, respectively, compared to 697.41 °C for the non-catalytic process. Moreover, the reactivity at 50 % of char conversion for the catalytic process (0.34 and 0.38 min-1 for Ce/pumice and Ni/pumice, respectively) was higher than for the non-catalytic process (0.28 min-1), indicating that the incorporation of Ce and Ni on the pumitic material increases the gasification rate of the char compared to the pumitic support. Catalytic biomass gasification is an innovative technology that can provide new opportunities for research and development of renewable energy technologies, as well as for the creation of green jobs.


Assuntos
Gases , Silicatos , Biomassa , Gases/química , Catálise
3.
Cryo Letters ; 42(2): 106-110, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33970987

RESUMO

BACKGROUND: Teramnus labialis (L.f.) Spreng is a potentially important legume species, and can be used as an animal feed and to enhance soil physicochemical characteristics. Despite the biological and agricultural importance, the low availability of seeds, their small size and the low percentage germination limit their large-scale use by farmers. We previously reported a method to cryopreserve seeds of T. labialis which also allowed for the breaking of seed dormancy. OBJECTIVE: The current study reports on the nutritional status of 5 month old field grown plants regenerated from cryostored and control seeds. MATERIALS AND METHODS: Biomass (fresh and dry mass of leaves and stems) and contents of ash, neutral detergent fiber, acid detergent fiber, lignin, cellulose, crude protein, P, Ca, Mg and K were measured. RESULTS: Seeds germinated and emerged faster following immersion in liquid nitrogen (LN) which was supported by quantitative evaluations of fresh and dry weights per m2. However, the ratio of leaf:stem mass were not altered by seed exposure to LN. CONCLUSION: The results showed that exposure of seeds to cryogenic temperatures did not alter the nutritional composition of regenerated plants.


Assuntos
Criopreservação , Fabaceae/química , Estado Nutricional , Sementes/fisiologia , Germinação , Nitrogênio
7.
Neurology ; 78(18): 1394-400, 2012 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-22517102

RESUMO

OBJECTIVE: To determine the frequency of spinal neurocysticercosis (NCC) in patients with basal subarachnoid NCC compared with that in individuals with viable limited intraparenchymal NCC (≤20 live cysts in the brain). METHODS: We performed a prospective observational case-control study of patients with NCC involving the basal cisterns or patients with only limited intraparenchymal NCC. All patients underwent MRI examinations of the brain and the entire spinal cord to assess spinal involvement. RESULTS: Twenty-seven patients with limited intraparenchymal NCC, and 28 patients with basal subarachnoid NCC were included in the study. Spinal involvement was found in 17 patients with basal subarachnoid NCC and in only one patient with limited intraparenchymal NCC (odds ratio 40.18, 95% confidence interval 4.74-340.31; p < 0.0001). All patients had extramedullary (intradural) spinal NCC, and the lumbosacral region was the most frequently involved (89%). Patients with extensive spinal NCC more frequently had ventriculoperitoneal shunt placement (7 of 7 vs 3 of 11; p = 0.004) and tended to have a longer duration of neurologic symptoms than those with regional involvement (72 months vs 24 months; p = 0.062). CONCLUSIONS: The spinal subarachnoid space is commonly involved in patients with basal subarachnoid NCC, compared with those with only intraparenchymal brain cysts. Spinal cord involvement probably explains serious late complications including chronic meningitis and gait disorders that were described before the introduction of antiparasitic therapy. MRI of the spine should be performed in basal subarachnoid disease to document spinal involvement, prevent complications, and monitor for recurrent disease.


Assuntos
Imageamento por Ressonância Magnética , Neurocisticercose/diagnóstico , Doenças da Coluna Vertebral/diagnóstico , Espaço Subaracnóideo , Tomografia Computadorizada por Raios X , Adolescente , Adulto , Idoso , Encéfalo/patologia , Estudos de Casos e Controles , Estudos Transversais , Progressão da Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neurocisticercose/epidemiologia , Exame Neurológico , Peru , Medula Espinal/patologia , Doenças da Coluna Vertebral/epidemiologia , Derivação Ventriculoperitoneal , Adulto Jovem
8.
Fetal Diagn Ther ; 31(2): 109-14, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22377693

RESUMO

OBJECTIVE: To assess the potential value of maternal serum alpha-fetoprotein (AFP) at 11-13 weeks' gestation in early screening for fetal neural tube defects (NTDs). METHODS: Maternal serum AFP at 11-13 weeks' gestation was measured in 32 cases of fetal NTDs, including 18 cases of acrania and 14 cases of spina bifida, and 1,500 unaffected controls. The measured serum AFP was converted into multiple of the expected median (MoM) after adjustment for gestational age and maternal characteristics and Mann-Whitney test was used to determine the significance of difference in the mean MoM of serum AFP in the NTD group to that in the controls. RESULTS: The mean AFP MoM in the NTD group (1.76, 95% CI 1.39-2.23) was significantly higher than in the controls (p < 0.0001). The mean AFP MoM was not significantly different between the cases of acrania and cases of spina bifida (1.78 vs. 1.75; p = 0.722). The detection rates of NTD in screening by serum AFP were 50.0% (95% CI 31.9-68.1) and 37.5% (95% CI 21.1-56.3) at fixed false-positive rates of 10 and 5%, respectively. CONCLUSION: Measurement of maternal serum AFP at 11-13 weeks' gestation may be useful in screening for fetal NTDs.


Assuntos
Defeitos do Tubo Neural/sangue , Defeitos do Tubo Neural/diagnóstico , Diagnóstico Pré-Natal/métodos , alfa-Fetoproteínas/metabolismo , Adulto , Biomarcadores/sangue , Estudos de Casos e Controles , Feminino , Idade Gestacional , Humanos , Recém-Nascido , Programas de Rastreamento/métodos , Programas de Rastreamento/estatística & dados numéricos , Valor Preditivo dos Testes , Gravidez , Primeiro Trimestre da Gravidez , Diagnóstico Pré-Natal/estatística & dados numéricos , Estudos Prospectivos , Disrafismo Espinal/sangue , Disrafismo Espinal/diagnóstico , Adulto Jovem
9.
Rev Neurol ; 48(2): 66-70, 2009.
Artigo em Espanhol | MEDLINE | ID: mdl-19173203

RESUMO

INTRODUCTION: Between 60 and 65% of the mutations that cause Duchenne's/Becker's muscular dystrophy (DMD/BMD) are deletions in the dystrophin gene. Identifying deletions confirms the diagnosis and allows carriers to be detected with precision, which is the main preventive resource. The frequency and distribution of deletions in the DMD gene is unknown in south-east Mexico. AIMS: To identify deletions in the DMD gene and to detect carriers in families with DMD/BMD in south-east Mexico. PATIENTS AND METHODS: The study involved 26 families that showed clinical signs of DMD/BMD: Deletions were determined in the DNA of 40 males by means of the multiple polymerase chain reaction (PCR) in 22 segments of the gene. Detection of carriers was applied to 33 female relatives using PCR-restriction fragment length polymorphism of the polymorphic markers Pert 87.8/Taq 1, pERT 87.15/Bam H1, and single PCR for VNTR MP1P by linkage analysis. RESULTS: Deletions were identified in 67.5% of patients with DMD and they were located in the 5' end and in the central region, exons 44 to 52, of the gene. In the detection of carriers, 73.33% of the families were informative. The markers 87.8/Taq 1 and MPIP yielded the greatest information power, with 26.67 and 33.33%, respectively. Of a total of 33 females, 21 (63.64%) were carriers, one (3.03%) was a non-carrier and 11 (33.33%) were not informative. CONCLUSIONS: The frequency of deletions was 67.5%. Carrier status was determined in 66.67% of the females who were analysed. The markers pERT 87.8/Taq 1 and MP1P yielded the greatest information power.


Assuntos
Distrofina/genética , Triagem de Portadores Genéticos , Distrofia Muscular de Duchenne/genética , Deleção de Sequência , Adolescente , Criança , Pré-Escolar , Cromossomos Humanos X/genética , Distrofina/deficiência , Éxons/genética , Feminino , Frequência do Gene , Marcadores Genéticos , Humanos , Lactente , Masculino , México , Repetições Minissatélites , Distrofia Muscular de Duchenne/epidemiologia , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Adulto Jovem
10.
Rev. neurol. (Ed. impr.) ; 48(2): 66-70, 16 ene., 2009. ilus
Artigo em Es | IBECS | ID: ibc-71857

RESUMO

Introducción. Del 60 al 65% de las mutaciones que causan distrofia muscular de Duchenne/Becker (DMD/DMB)corresponden a deleciones en el gen de la distrofina. La identificación de deleciones confirma el diagnóstico y permite la detección precisa de portadoras, que es el recurso principal de prevención. En el sudeste de México se desconoce la frecuencia y distribución de las deleciones del gen DMD. Objetivos. Identificar deleciones del gen DMD y detectar portadoras en familiascon DMD/DMB del sudeste de México. Pacientes y métodos. Se incluyeron 26 familias cuyo propósito mostró signos clínicos de DMD/DMB. Las deleciones se determinaron en el ADN de 40 varones mediante reacción en cadena de la polimerasa (PCR) múltiple de 22 segmentos del gen. La detección de portadoras se aplicó a 33 familiares femeninos con PCR mediante polimorfismo de longitud de fragmentos de restricción de los marcadores Pert 87.8/Taq 1, pERT 87.15/Bam H1, y PCR simplepara el VNTR MPIP mediante análisis de ligamiento. Resultados. Las deleciones se identificaron en el 67,5% de pacientes con DMD y se localizaron en el extremo 5’ y en la región central, exones 44 al 52, del gen. En la detección de portadoras, el 73,33% de las familias resultó informativo. Los marcadores 87.8/Taq I y MPIP arrojaron el mayor poder de información, con el 26,67 y el 33,33%, respectivamente. De 33 mujeres, 21 (63,64%) resultaron portadoras, una (3,03%) no portadora y 11 (33.33%) no fueron informativas. Conclusión. La frecuencia de deleciones fue del 67,5%. Se determinó el estado de portador en el 66,67% de las mujeres analizadas. Los marcadores pERT 87.8/Taq 1 y MPIP arrojaron el mayor poder de información


Introduction. Between 60 and 65% of the mutations that cause Duchenne’s/Becker’s muscular dystrophy (DMD/BMD)are deletions in the dystrophin gene. Identifying deletions confirms the diagnosis and allows carriers to be detected with precision, which is the main preventive resource. The frequency and distribution of deletions in the DMD gene is unknown in south-east Mexico. Aims. To identify deletions in the DMD gene and to detect carriers in families with DMD/BMD in south-eastMexico. Patients and methods. The study involved 26 families that showed clinical signs of DMD/BMD. Deletions were determined in the DNA of 40 males by means of the multiple polymerase chain reaction (PCR) in 22 segments of the gene. Detection of carriers was applied to 33 female relatives using PCR-restriction fragment length polymorphism of the polymorphicmarkers Pert 87.8/Taq 1, pERT 87.15/Bam H1, and single PCR for VNTR MP1P by linkage analysis. Results. Deletionswere identified in 67.5% of patients with DMD and they were located in the 5’ end and in the central region, exons 44 to 52, of the gene. In the detection of carriers, 73.33% of the families were informative. The markers 87.8/Taq 1 and MPIP yielded thegreatest information power, with 26.67 and 33.33%, respectively. Of a total of 33 females, 21 (63.64%) were carriers, one (3.03%) was a non-carrier and 11 (33.33%) were not informative. Conclusions. The frequency of deletions was 67.5%. Carrier status was determined in 66.67% of the females who were analysed. The markers pERT 87.8/Taq 1 and MP1P yielded the greatest information power


Assuntos
Humanos , Distrofia Muscular de Duchenne/epidemiologia , Distrofia Muscular de Duchenne/genética , Deleção Cromossômica , Distrofina/genética , Mutação , Marcadores Genéticos , Heterozigoto
11.
An Pediatr (Barc) ; 64(1): 5-10, 2006 Jan.
Artigo em Espanhol | MEDLINE | ID: mdl-16539910

RESUMO

INTRODUCTION: Consanguineous unions occur in all populations around the world. Couples related as second cousins or closer have been observed with deleterious effect. Among the clinical effects of parental consanguinity, the incidence of offspring with congenital malformations (CM) increases approximately two-fold. MATERIALS AND METHODS: A hospital database of neonates with CM was searched to select neonates with parental consanguinity and two control groups. One control group consisted of healthy neonates and the other control group consisted of neonates with CM but without parental consanguinity. Both control groups consisted of the first neonate of the same sex to be born after a consanguineous neonate with CM. Family, sociodemographic and anthropometric variables, as well as the severity of the malformations, were compared between the two groups with CM. Neonates with CM were grouped into five categories: Major multiple CM, minor multiple CM, isolated major CM, isolated minor CM, and specific diseases. The indigenous Mayan subpopulation was also analyzed. RESULTS: Among 1117 neonates with CM, parental consanguinity was found in 21. Parental consanguinity was also found in 8 neonates in the group of healthy controls (OR 2.4 [1.05-5.95]). The most common form of consanguinity was between second cousins and was more frequent in the Mayan subpopulation. Major multiple CM were more frequent among consanguineous than among nonconsanguineous couples. No association was found between the severity of CM and the degree of relationship. CONCLUSIONS: The prevalence of consanguinity found in neonates with CM and healthy controls (1.9 % and 0.8 %) was similar to that found in other Latin populations. A higher prevalence was found in the Mayan population. Mayor multiple CM were more frequent among the neonates of consanguineous than among nonconsanguineous couples.


Assuntos
Anormalidades Congênitas/epidemiologia , Consanguinidade , Humanos , Recém-Nascido , México/epidemiologia
12.
An. pediatr. (2003, Ed. impr.) ; 64(1): 5-10, ene. 2006. tab
Artigo em Es | IBECS | ID: ibc-044485

RESUMO

Introducción Las uniones consanguíneas ocurren en todas las poblaciones, las de primos segundos o con parentesco más cercano son las que se han observado con influencia genética. Entre las posibles consecuencias clínicas, se estima que se incrementa al doble el riesgo de tener descendencia con malformaciones congénitas (MC). Material y métodos De un registro hospitalario de recién nacidos (RN) con MC, se seleccionó a los que tuvieron antecedente de consanguinidad, y dos grupos controles, uno sano y otro malformado sin antecedentes de consanguinidad, correspondiente a los nacimientos siguientes al malformado consanguíneo del mismo sexo. Se analizaron variables familiares, sociodemográficas y antropométricas, así como la gravedad de las MC entre los dos grupos malformados. Los RN con MC se agruparon en cinco categorías: MC múltiples mayores (MC Múlt1), MC múltiples menores (MC Múlt­), MC aisladas mayores (MC Ais1), MC aisladas menores (MC Ais­), y patologías específicas. Adicionalmente, se analizó a la subpoblación indígena maya. Resultados De 1.117 RN con MC, se encontró antecedente de consanguinidad en 21, y 8 entre los controles sanos, odds ratio 2,4 (1,05-5,95). El grado de parentesco más frecuente fue el de primos segundos, con mayor frecuencia de consanguinidad en el grupo étnico maya. Se encontró mayor número de afectados malformados múltiples entre las uniones consanguíneas, que entre las no consanguíneas. No hubo relación entre la gravedad de las MC y el parentesco. Conclusiones La prevalencia de consanguinidad de 1,9 y 0,8 % encontradas entre RN malformados y controles es similar a la de otras poblaciones latinas. El grupo étnico maya presentó mayor prevalencia, y las MC múltiples mayores fueron más frecuentes entre los malformados consanguíneos que entre los no consanguíneos


Introduction Consanguineous unions occur in all populations around the world. Couples related as second cousins or closer have been observed with deleterious effect. Among the clinical effects of parental consanguinity, the incidence of offspring with congenital malformations (CM) increases approximately two-fold. Materials and methods A hospital database of neonates with CM was searched to select neonates with parental consanguinity and two control groups. One control group consisted of healthy neonates and the other control group consisted of neonates with CM but without parental consanguinity. Both control groups consisted of the first neonate of the same sex to be born after a consanguineous neonate with CM. Family, sociodemographic and anthropometric variables, as well as the severity of the malformations, were compared between the two groups with CM. Neonates with CM were grouped into five categories: Major multiple CM, minor multiple CM, isolated major CM, isolated minor CM, and specific diseases. The indigenous Mayan subpopulation was also analyzed. Results Among 1117 neonates with CM, parental consanguinity was found in 21. Parental consanguinity was also found in 8 neonates in the group of healthy controls (OR 2.4 [1.05-5.95]). The most common form of consanguinity was between second cousins and was more frequent in the Mayan subpopulation. Major multiple CM were more frequent among consanguineous than among nonconsanguineous couples. No association was found between the severity of CM and the degree of relationship. Conclusions The prevalence of consanguinity found in neonates with CM and healthy controls (1.9 % and 0.8 %) was similar to that found in other Latin populations. A higher prevalence was found in the Mayan population. Mayor multiple CM were more frequent among the neonates of consanguineous than among nonconsanguineous couples


Assuntos
Recém-Nascido , Humanos , Anormalidades Congênitas/epidemiologia , Consanguinidade , México/epidemiologia
13.
Leg Med (Tokyo) ; 8(1): 52-4, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16213776

RESUMO

The pentanucleotide STR (TAAAA)n DXYS156 offers advantages for genetic identity testing. In addition to establish the gender, DXYS156 expands the DNA profile and is able to indicate the possible geographic origin of the individual. We analyzed DXYS156 in 757 individuals of both sexes from Mexican populations. We studied the cosmopolitan Mestizo population and six Mexican ethnic groups: Tarahumaras, Purépechas, Nahuas, Mayas, Huicholes and Mezcala Indians. The six shorter (4-10) and the three larger alleles (11-13) were specific for the X and Y-chromosomes, respectively. A random distribution of alleles into genotypes was observed in males and females from each population. We estimated the power of exclusion for paternity testing according to the son's gender, and the power of discrimination in forensic casework. In addition, we detected a relatively high frequency of an X-linked allele null, principally in Mexican-Mestizos (3.6%), which must be considered when DXYS156 be applied for identification purposes.


Assuntos
Cromossomos Humanos X , Frequência do Gene , Genética Populacional , Sequências de Repetição em Tandem , Cromossomos Humanos Y , Impressões Digitais de DNA , Etnicidade/genética , Feminino , Humanos , Masculino , México
14.
Clin Genet ; 62(5): 394-8, 2002 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-12431255

RESUMO

The C677T variant in the MTHFR gene is considered to be an associated risk factor for neural tube defects. However, the association has not been found in some ethnic groups. In order to assess the association between neural tube defects and the C677T variant, we determined the frequency of this variant in the MTHFR gene in the State of Yucatan, Mexico, where neural tube defects are highly prevalent. The study was performed on 65 subjects with spine bifida, 60 of their mothers and 110 control subjects. The presence of the C677T variant was determined by amplification and digestion with HinF1 of each subject's DNA. Genotypic and allelic frequencies were calculated for all groups. We did not observe any statistically significant difference in the genotypic or allelic frequencies between cases and controls for any of the groups studied (p > 0.05), suggesting that the thermolabile variant C677T is not an associated risk factor neither for the development of neural tube defects nor for mothers to have affected offspring in the population from Yucatan. Interestingly, the frequency of the C677T variant (54%) obtained in the Yucatan population is one of the highest reported (p < 0.01) and confirmed the high frequency of this allele throughout Mexico.


Assuntos
Frequência do Gene , Defeitos do Tubo Neural/genética , Oxirredutases atuantes sobre Doadores de Grupo CH-NH/genética , Feminino , Genótipo , Humanos , Recém-Nascido , Metilenotetra-Hidrofolato Redutase (NADPH2) , México , Defeitos do Tubo Neural/enzimologia , Gravidez
15.
Rev Neurol ; 34(8): 745-50, 2002.
Artigo em Espanhol | MEDLINE | ID: mdl-12080495

RESUMO

CASE REPORT: A clinical case of Wilson's disease is presented. She was a 26 years old woman who began to show psychological symptoms, and later developed neurological signs such as asymmetrical hand tremor, parkinsonism, dystonia and later dysphagia and mutism. The ophthalmological examination found a Kayser Fleischer ring in the Descemet membrane. There was disturbance of copper metabolism documented with reduction of serum ceruloplasmin and increase of the urinary excretion of copper. Cirrhosis was demonstrated through laparoscopy and liver biopsy. RESULTS: The brain magnetic resonance showed frontotemporal atrophy and a degenerative process at the basal ganglia, cerebellum and brain stem, data which could de used to suggest the probable neuropsychiatric physiopathology. The stenosis and intense cervical dysphagia, associated with crycopharyngeal membrane, has not been mentioned previously.


Assuntos
Encéfalo/patologia , Degeneração Hepatolenticular/diagnóstico , Degeneração Hepatolenticular/fisiopatologia , Adulto , Cobre/metabolismo , Olho/patologia , Feminino , Degeneração Hepatolenticular/patologia , Humanos , Imageamento por Ressonância Magnética , Testes Neuropsicológicos
16.
Rev. neurol. (Ed. impr.) ; 34(8): 745-750, 16 abr., 2002.
Artigo em Es | IBECS | ID: ibc-27697

RESUMO

Caso clínico. Se presenta un caso clínico de la enfermedad de Wilson. Una mujer de 26 años de edad presentó trastornos psíquicos a los que se añadieron luego signos neurológicos tales como temblor asimétrico de las manos, parkinsonismo y distonía; más tarde tuvo mutismo y disfagia. La exploración oftalmológica demostró la presencia del anillo de Kayser-Fleischer en la membrana de Descemet. Se comprobó una alteración en el metabolismo del cobre que consiste en reducción de la ceruloplasmina sérica y aumento de la excreción urinaria de cobre. Mediante laparoscopia y biopsia se diagnosticó cirrosis hepática. Resultados. La investigación de las estructuras del encéfalo con resonancia magnética reveló atrofia frontotemporal del cerebro y proceso degenerativo de los ganglios basales, el cerebelo y el tronco encefálico, datos que podrían explicar la sintomatología neuropsiquiátrica. La asociación con membrana cricofaríngea, causante de estenosis y disfagia cervical intensa, no se ha mencionado anteriormente (AU)


No disponible


Assuntos
Adulto , Feminino , Humanos , Cobre , Degeneração Hepatolenticular , Imageamento por Ressonância Magnética , Olho , Testes Neuropsicológicos , Telencéfalo
17.
Lipids ; 36(1): 49-55, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11214729

RESUMO

Alpha-Tocopherol (alpha-TH) undergoes ultraviolet (UV)-induced photooxidation on the surface of mouse skin to produce a dihydroxydimer, a spirodimer, and trimers as the major products. To study the photochemistry involved, we UV-irradiated alpha-TH in a thin film on a glass petri dish. Photooxidation yielded a mixture of dihydroxydimer, spirodimer, and trimers. In the time-course studies, the dihydroxydimer accumulated and then was further oxidized, whereas the spirodimer and trimers accumulated more gradually. Reaction of two tocopheroxyl radicals forms the dihydroxydimer, whereas the spirodimer may be formed either by photooxidation of alpha-TH to an orthoquinone methide (o-QM) followed by a Diels-Alder reaction or by photooxidation of alpha-TH to the dihydroxydimer, followed by two-electron oxidation. Irradiation of a mixture of d10-labeled and unlabeled (d0) dihydroxydimer produced a mixture of labeled and unlabeled spirodimers as detected by positive atmospheric pressure chemical ionization-mass spectrometry. The absence of mixed label spirodimers among products indicated that direct oxidation of the dihydroxydimer is a facile route to the spirodimer and is probably the major spirodimer-forming reaction in alpha-TH photooxidations. Trimer formation from the dihydroxydimer and the spirodimer was observed, however, and requires an o-QM intermediate. Photooxidation of dl0-labeled and unlabeled (d0) dihydroxydimers yielded mixed isotopomers of the trimer products, thus demonstrating that the dihydroxydimer and spirodimers underwent conversion to o-QM intermediates. Photochemical conversion of alpha-TH to UV-absorbing dimer and trimer products may contribute to photoprotection by topically applied alpha-TH.


Assuntos
Raios Ultravioleta , Vitamina E/química , Vitamina E/efeitos da radiação , Fenômenos Químicos , Físico-Química , Dimerização , Espectrometria de Massas , Estrutura Molecular , Oxirredução , Fotoquímica , Espectrometria de Massas por Ionização por Electrospray
18.
Eur J Clin Nutr ; 54(1): 61-7, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10694774

RESUMO

OBJECTIVE: The objective of this trial was to compare the effect on the susceptibility of plasma Low Density Lipoprotein (LDL) to oxidative modifications of consumption of two oleic rich diets, prepared with two different plant oils, virgin olive oil (OL)1 and refined high monounsaturated fatty acids (MUFA sunflower oil (SU)), with the susceptibility of plasma LDL to oxidation after an National Cholesterol Education Program step 1 (NCEP-I) phase diet. DESIGN: A randomized crossover design. SUBJECTS AND INTERVENTIONS: Twenty-two healthy normolipidemic young males consumed an NCEP-I diet for a 4-week period. Subjects were then assigned to two diets each of 4-weeks duration. Group one was placed on an olive oil enriched diet (40% fat, 22% MUFA) followed by a 4-week period of a MUFA diet enriched in sunflower oil (40% fat, 22% MUFA). In group two, the order of the diets was reversed. RESULTS: Both MUFA diets induced a decrease in saturated (14:0, 16:0, and 18:0) and an increase in monounsaturated and polyunsaturated n-6 (18:2, 20:3, and 20:5) plasma LDL-phospholipid fatty acids, compared to the NCEP-I diet (P<0.01). No significant differences in lag times were observed between the olive oil and the NCEP-I diet periods. However there was a greater inhibition time (P<0.001) when subjects consumed the MUFA rich sunflower oil diet compared to the NCEP-I diet. These differences were probably related to the relative enrichment of plasma LDL particles in alpha-tocopherol due to the high vitamin E content of the MUFA-rich sunflower oil. Indeed, the alpha-tocopherol content was positively correlated with lag time (r=0.338; P<0.008). CONCLUSION: Our findings suggest that changes in plasma LDL alpha-tocopherol content with practical solid-food diets can decrease its susceptibility to oxidation. SPONSORSHIP: This work has been supported by grants from the Investigaciones de la Seguridad Social (FIS 92/0182, to Francisco Pérez Jiménez); and from Koype Co, Andújar, Jaén, Spain. European Journal of Clinical Nutrition (2000) 54, 61-67


Assuntos
Gorduras na Dieta/farmacologia , Ácidos Graxos Monoinsaturados/farmacologia , Lipoproteínas LDL/sangue , Adulto , Análise de Variância , Índice de Massa Corporal , Estudos Cross-Over , Gorduras na Dieta/administração & dosagem , Gorduras Insaturadas na Dieta/administração & dosagem , Gorduras Insaturadas na Dieta/farmacologia , Ácidos Graxos Monoinsaturados/administração & dosagem , Humanos , Masculino , Azeite de Oliva , Oxirredução/efeitos dos fármacos , Óleos de Plantas/administração & dosagem , Óleos de Plantas/farmacologia , Óleo de Girassol , Vitamina E/sangue
19.
Am J Clin Nutr ; 68(5): 1028-33, 1998 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9808218

RESUMO

BACKGROUND: The fatty acid composition of the diet can modulate the effect of dietary cholesterol on plasma lipoproteins. However, HDL composition and its capacity to promote cholesterol efflux can be influenced by the diet. OBJECTIVE: Modifications in plasma lipids and in the capacity of serum to stimulate the cholesterol efflux induced by a low-fat diet [National Cholesterol Education Program (NCEP) Step I diet], by a monounsaturated fatty acid (MUFA)-rich diet, and by addition of cholesterol to both diets was studied. DESIGN: Fifteen young, healthy men followed 2 NCEP Step I diets (<30% of fat as energy, with <10% saturated fat and 14% MUFAs) for 24 d, providing 0.027 or 0.068 mg cholesterol x kJ(-1) x d(-1), and 2 oleic acid-enriched diets (38% of energy as fat, with 24% MUFAs) providing the same amount of dietary cholesterol as the NCEP Step I diets. RESULTS: Total cholesterol, LDL cholesterol, apolipoprotein (apo) B, and apo A-I concentrations decreased after the NCEP Step I and MUFA diets compared with the usual diet. HDL cholesterol also decreased after the NCEP Step I diet. Total:HDL cholesterol, apo B, and apo B:apo A-I were lower after the MUFA diets than after the NCEP Step I diets. There were no significant differences between the lipid profiles obtained after the NCEP Step I and MUFA diets were enriched with cholesterol. The capacity of serum to promote cholesterol efflux was significantly higher after the cholesterol-enriched NCEP Step I diet than after the NCEP Step I diet. CONCLUSIONS: The MUFA diet induced a better lipid profile than the NCEP Step I diet; however, the increase in the cholesterol content of both diets produced similar plasma lipid changes. The cholesterol in the NCEP Step I diet increased the cholesterol efflux induced by total serum.


Assuntos
Colesterol na Dieta/administração & dosagem , Colesterol/sangue , Ácidos Graxos Monoinsaturados/administração & dosagem , Lipoproteínas/sangue , Neoplasias Hepáticas Experimentais/metabolismo , Adulto , Animais , Colesterol/metabolismo , Colesterol na Dieta/farmacologia , Ingestão de Energia , Humanos , Masculino , Células Tumorais Cultivadas
20.
Am J Med Genet ; 76(2): 150-3, 1998 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-9511978

RESUMO

We describe an abnormal premature male infant with mosaic monosomy of chromosome 22. He had a unique facial appearance, similar to those with DiGeorge syndrome, and hypertonicity, limitation of extension at major joints, and flexion contractures of all fingers. This rare chromosomal aberration has been reported previously in 6 cases, three of them being nonmosaic and three mosaic patients. There was a great variability of expression among the anomalies of these patients. However, the most common anomalies were in the face and joints. A correlation between the severity of expression and percent of monosomic cells was not clear.


Assuntos
Cromossomos Humanos Par 22 , Síndrome de DiGeorge/genética , Monossomia , Mosaicismo , Humanos , Recém-Nascido , Masculino
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