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3.
Science ; 331(6017): 575-8, 2011 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-21292976

RESUMO

Despite radically different environmental conditions, terrestrial and martian dunes bear a strong resemblance, indicating that the basic processes of saltation and grainfall (sand avalanching down the dune slipface) operate on both worlds. Here, we show that martian dunes are subject to an additional modification process not found on Earth: springtime sublimation of Mars' CO(2) seasonal polar caps. Numerous dunes in Mars' north polar region have experienced morphological changes within a Mars year, detected in images acquired by the High-Resolution Imaging Science Experiment on the Mars Reconnaissance Orbiter. Dunes show new alcoves, gullies, and dune apron extension. This is followed by remobilization of the fresh deposits by the wind, forming ripples and erasing gullies. The widespread nature of these rapid changes, and the pristine appearance of most dunes in the area, implicates active sand transport in the vast polar erg in Mars' current climate.


Assuntos
Dióxido de Carbono , Marte , Gelo-Seco , Meio Ambiente Extraterreno
5.
Arch Dis Child ; 96(6): 565-6, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20584847

RESUMO

An algorithm is described whereby the threshold for thyroid-stimulating hormone used in neonatal screening for congenital hypothyroidism is re-set for each run on the basis of the variation and values of measurements of certified samples.


Assuntos
Hipotireoidismo Congênito/diagnóstico , Tireotropina/sangue , Algoritmos , Biomarcadores/sangue , Humanos , Recém-Nascido , Triagem Neonatal/métodos , Valores de Referência
6.
Mol Genet Metab ; 101(2-3): 95-8, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20638312

RESUMO

After briefly recalling the main events leading to the establishment of newborn screening programmes, this paper details the early history of their introduction in Spain and sketches their expansion to cover the whole Spanish population. Spain is exceptional in that its screening methods have in general been based on planar chromatographic techniques developed or inspired by Louis I. Woolf, rather than on bacterial inhibition tests, as is illustrated by the practice of the newborn screening laboratory of Galicia (N.W. Spain).


Assuntos
Triagem Neonatal/história , História do Século XX , História do Século XXI , Humanos , Recém-Nascido , Programas de Rastreamento , Erros Inatos do Metabolismo/diagnóstico , Erros Inatos do Metabolismo/história , Fenilcetonúrias/diagnóstico , Fenilcetonúrias/história , Espanha
7.
J Clin Lab Anal ; 24(3): 149-53, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20486194

RESUMO

BACKGROUND: The fact that mucopolysaccharidoses (MPSes) are now treatable, and that the earlier treatment is initiated the better, is an indication for neonatal screening. The most efficient approach seems likely to be a multi-tier procedure in which screening for urinary glycosaminoglycan (GAG) is followed by enzyme determinations in heelprick blood of newborns screening positive. Hitherto the method of choice for the determination of GAG has been the measurement of absorbance by a complex of GAG and 1,9-dimethylmethylene blue (DMB). METHOD: We evaluated a DMB method in which absorbance by DMB is measured following its addition to the eluate obtained from paper-borne newborn urine samples and is normalized relative to urinary creatinine. Calibration is performed with chondroitin-6-sulfate (Ch-6-S). RESULTS: The limits of detection and quantification of GAG were 1.98 and 5.94 mg/dl, respectively. The within-run coefficients of variation (CVs) of the GAG/creatinine ratio for 25, 31, and 70 mg/dl solutions of Ch-6-S in urine were 21.8, 16.4, and 10.5%, respectively, and the corresponding between-run CVs were 25.0, 13.5, and 10.1%. Recovery from the urine spiked with 31 mg Ch-6-S/dl was 94.8%. Accuracy was also acceptable for all other GAGs except hyaluronic acid. For neonatal screening, the diagnostic threshold was tentatively established as 800 mg GAG/g creatinine, the 95th centile of samples from 903 infants aged 3-28 days, but the value of the GAG/creatinine ratio was negatively correlated with age. Application of the new method to samples from older individuals with and without MPS achieved 100% sensitivity and specificity when used with an age-dependent threshold taken from the literature on the original DMB method. CONCLUSION: If used in the first tier of a multi-tier screening protocol, the proposed method would allow the detection of abnormal levels of all GAGs except hyaluronic acid.


Assuntos
Glicosaminoglicanos/urina , Azul de Metileno/análogos & derivados , Mucopolissacaridoses/diagnóstico , Mucopolissacaridoses/urina , Triagem Neonatal/métodos , Papel , Envelhecimento/urina , Calibragem , Sulfatos de Condroitina/química , Sulfatos de Condroitina/urina , Creatinina/urina , Dermatan Sulfato/química , Dermatan Sulfato/urina , Glicosaminoglicanos/química , Heparina/química , Heparina/urina , Heparinoides/química , Heparinoides/urina , Humanos , Ácido Hialurônico/química , Ácido Hialurônico/urina , Recém-Nascido , Azul de Metileno/química , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
8.
J Med Screen ; 16(4): 205-11, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-20054096

RESUMO

Early diagnosis of phenylketonuria (PKU) became a goal worth pursuing following demonstration of the efficacy of the dietary treatment conceived by Louis I Woolf. This paper narrates the history of this treatment, describes Woolf's role in the establishment of neonatal PKU screening and surveys his other contributions to our understanding of this condition. If Woolf, Centerwall, Baird and Berry had waited until all the scientific evidence about PKU that is now at our disposal had been brought to light, there would still be no neonatal screening programmes.


Assuntos
Fenilcetonúrias/diagnóstico , Diagnóstico Precoce , Genética Populacional , História do Século XX , Humanos , Recém-Nascido , Triagem Neonatal , Fenilcetonúrias/dietoterapia , Fenilcetonúrias/genética
9.
J Cyst Fibros ; 7(6): 520-2, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18676185

RESUMO

We report three novel CFTR missense mutations detected in Spanish patients from Galicia (North West of Spain). In the first case, a patient homozygous for a novel S1045Y mutation died due to pulmonary problems. In the other two cases, both heterozygous for novel mutations combined with the F508del mutation, clinical symptoms were different depending on the mutation, detected as M595I and A107V.


Assuntos
Regulador de Condutância Transmembrana em Fibrose Cística/genética , Fibrose Cística/genética , Mutação de Sentido Incorreto/genética , Adolescente , Adulto , Fibrose Cística/complicações , Fibrose Cística/patologia , Éxons/genética , Feminino , Humanos , Masculino , Espanha
10.
P. R. health sci. j ; P. R. health sci. j;23(2): 95-101, Jun. 2004.
Artigo em Inglês | LILACS | ID: lil-390796

RESUMO

OBJECTIVES: The goals of these studies were to characterize the interaction of the P22 phage particle with the Salmonella cell surface and to determine the phage elements involved in this interaction by mutational analysis. BACKGROUND: The phage P22 has been characterized extensively. The gene and protein for the phage P22 tailspike, which is the phage adsorption organelle, have been intensively studied. The kinetics of the interaction of the tailspike protein with the cell surface has been studied in detail, surprisingly no mutational analysis has ever been reported that has defined these components and their interaction between themselves and the cell surface. The main and perhaps only component needed for this cell surface interaction is the tailspike protein. METHODS: Adsorption to the cell surface has been measured in the wild type phage and in mutant derivatives, isolated in this study. Phage mutants have been isolated after hydroxylamine mutagenesis. RESULTS: The adsorption of P22 to the cell surface is a temperature-independent event. Forty putative phage adsorption mutants have been isolated. A sample of them have been further analyzed. These divide the adsorption process into at least two stages. One stage contains mutants that absorb with essential wild type phage kinetics to the cell surface while the other stage with delayed adsorption kinetics. CONCLUSIONS: The interaction of the phage P22 with the Salmonella cell surface has been shown to be a complicated one which is temperature-independent and multi-stage. Mutants isolated in this study may help dissect this process even further


Assuntos
Humanos , Adsorção , /metabolismo , Salmonella typhimurium/virologia , /ultraestrutura , Lipopolissacarídeos/metabolismo , Proteínas da Cauda Viral/metabolismo , Salmonella typhimurium/metabolismo , Salmonella typhimurium/ultraestrutura , Temperatura
11.
J Med Primatol ; 31(4-5): 217-27, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12390544

RESUMO

The ever increasing number of people infected by human immunodeficiency virus (HIV) throughout the world renders the development of effective vaccines an urgent priority. Herein, we report on an attempt to induce and enhance antiviral responses using a deoxyribonucleic acid (DNA) prime/virus-like particles (VLP) protein boost strategy adjuvanted with interleukin (IL)-12/GM-CSF in rhesus macaques challenged with simian immunodeficiency virus (SIV). Thus, groups of monkeys were administered three consecutive doses of pVecB7 a plasmid expressing VLP with or without plasmids expressing IL-12 and GM-CSF at weeks 0, 13 and 26. The VLP boost was administered at week 39 with or without IL-12. All monkeys were challenged intrarectally with SIVsmE660 2 months following the protein boost. All except one immunized monkey became infected. While all immunized monkeys showed a marked reduction of acute viral peaks, reduction of viral load set points was only achieved in groups whose prime-boost immunizations were supplemented with IL-12/GM-CSF (prime) and/or with IL-12 (boost). Control of viremia correlated with lack of disease progression and survival. Detection of virus in rectal washes at 1 year post-challenge was only successful in monkeys whose immunizations did not include cytokine adjuvant, but these loads did not correlate with plasma viral loads. In summary, use of IL-12 and/or GM-CSF was shown to provide significant differences in the outcome of SIV challenge of prime/boost immunized monkeys.


Assuntos
Fator Estimulador de Colônias de Granulócitos e Macrófagos/imunologia , Interleucina-12/imunologia , Macaca mulatta/imunologia , Vacinas contra a SAIDS/administração & dosagem , Vacinas contra a SAIDS/imunologia , Síndrome de Imunodeficiência Adquirida dos Símios/prevenção & controle , Vírus da Imunodeficiência Símia/imunologia , Adjuvantes Imunológicos , Animais , Anticorpos Antivirais/imunologia , Modelos Animais de Doenças , Progressão da Doença , Esquema de Medicação , Quimioterapia Combinada , Fator Estimulador de Colônias de Granulócitos e Macrófagos/administração & dosagem , Interleucina-12/administração & dosagem , Macaca mulatta/virologia , Síndrome de Imunodeficiência Adquirida dos Símios/imunologia , Síndrome de Imunodeficiência Adquirida dos Símios/virologia , Vírus da Imunodeficiência Símia/fisiologia , Taxa de Sobrevida , Fatores de Tempo , Vacinas de DNA/administração & dosagem , Vacinas de DNA/imunologia , Carga Viral
12.
J Immunol ; 165(4): 2271-7, 2000 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-10925316

RESUMO

Immune-mediated mechanisms have been implicated in the etiology of idiopathic bone marrow fibrosis (IMF). However, the mechanism remains poorly defined. Compared with healthy controls, IMF monocytes are overactivated, with increased production of TGF-beta and IL-1. TGF-beta is central to the progression of fibrosis in different organs. In the lung, fibrosis is associated with up-regulation of TGF-beta-inducible genes. Because IL-1 and TGF-beta have pro- and antiinflammatory properties and neither appears to regulate the high levels of each other in IMF, we studied the mechanism of this paradigm. We focused on the role of RelA, a subunit of the transcription factor, NF-kappaB that is associated with inflammatory responses. We transiently knocked out RelA from IMF monocytes with antisense oligonucleotides and showed that RelA is central to IL-1 and TGF-beta production and to the adhesion of IMF monocytes. Because the NF-kappaB family comprises subunits other than RelA, we used aspirin and sodium salicylate to inhibit kinases that activate NF-kappaB and showed effects similar to those of the RelA knockout system. It is unlikely that RelA could be interacting directly with the TGF-beta gene. Therefore, we determined its role in TGF-beta production and showed that exogenous IL-1 could induce TGF-beta and adherence of IMF monocytes despite the depletion of NF-kappaB. The results indicate that IL-1 is necessary for TGF-beta production in IMF monocytes, but NF-kappaB activation is required for the production of endogenous IL-1. Initial adhesion activates NF-kappaB, which led to IL-1 production. Through autocrine means, IL-1 induces TGF-beta production. In total, these reactions maintain overactivation of IMF monocytes.


Assuntos
Homeostase/imunologia , Monócitos/imunologia , Monócitos/metabolismo , NF-kappa B/fisiologia , Mielofibrose Primária/imunologia , Mielofibrose Primária/patologia , Fator de Crescimento Transformador beta/biossíntese , Adulto , Idoso , Animais , Transporte Biológico/imunologia , Medula Óssea/patologia , Adesão Celular/imunologia , Linhagem Celular , Núcleo Celular/imunologia , Núcleo Celular/metabolismo , Separação Celular , Humanos , Interleucina-1/fisiologia , Ligases/deficiência , Ligases/genética , Ligases/metabolismo , Ativação de Macrófagos , Camundongos , Pessoa de Meia-Idade , NF-kappa B/sangue , Oligonucleotídeos Antissenso/farmacologia , Mielofibrose Primária/sangue , Ratos
13.
J Bone Joint Surg Am ; 74(7): 1038-41, 1992 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-1522090

RESUMO

We evaluated the results of transfer of the tibialis anterior in the management of calcaneus deformity in young patients who had myelodysplasia; fifteen patients (twenty-two feet) were operated on between 1978 and 1985. The neural deficit was at the fourth and fifth lumbar levels. The average age at the time of the operation was seven years and two months (range, two to nineteen years). The average age at the latest follow-up was thirteen years (range, five to twenty-four years). The average duration of follow-up was five years and ten months (range, two to eleven years). Seventeen feet (twelve patients) had a good result (no ulceration of the heel or osteomyelitis and correction of the calcaneus deformity), and five feet (three patients) had a poor result (persistent ulceration, signs of osteomyelitis, recurrent or persistent calcaneus deformity, or the need for additional operative intervention). Children who were less than five years old had a better outcome, as determined by the Fisher exact test (p less than 0.5).


Assuntos
Calcâneo/anormalidades , Calcâneo/cirurgia , Defeitos do Tubo Neural/complicações , Transferência Tendinosa/métodos , Adolescente , Criança , Pré-Escolar , Seguimentos , Humanos , Satisfação do Paciente , Resultado do Tratamento
14.
Bol Asoc Med P R ; 82(2): 57-61, 1990 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-2322345

RESUMO

Recent literature reports an apparent decline in the incidence of neural tube defects throughout the world. A revision of stillbirth certificates and surgical reports of closure procedures for open neural tube defects was done in order to establish the incidence and its trend during a nine year period in Puerto Rico. The current prevalence of the syndrome was estimated using the death certificates in addition to the fore-mentioned surgical reports. Our results indicate that Puerto Rico carries probably the highest incidence of the US territories and that the trend is not declining one.


Assuntos
Defeitos do Tubo Neural/epidemiologia , Estudos de Coortes , Estudos Transversais , Feminino , Morte Fetal/epidemiologia , Humanos , Recém-Nascido , Gravidez , Porto Rico/epidemiologia
15.
Clin Orthop Relat Res ; (241): 224-30, 1989 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-2924469

RESUMO

External fixation is considered the treatment of choice for severe open tibial fractures. A prospective study was designed to evaluate the use of the Orthofix Dynamic Axial Fixator (DAF) for the short- and long-term treatment of open tibial fractures. Forty-four patients with 45 open tibial fractures were enrolled in the study, which included a one-year follow-up period. Eighty-nine percent of the fractures were classified as Gustilo and Anderson's Type III. All fractures except one were united in a mean healing time of 22.6 weeks. The dynamization of the Orthofix in nonsegmental fractures occurred at an average of 8.1 weeks. Segmental fractures received a two-stage dynamization. The first stage consisted of removing the supplementary pins, once callus formation was seen at one of the fractures lines, plus the addition of a bone graft. This stage occurred at an average of 8.8 weeks. The second stage consisted of unlocking the telescoping rods and allowing dynamic axial loading of the consolidating graft. This stage occurred at an average of 19.0 weeks. The implementation of this one-plane unilateral frame, which is capable of converting from a rigid to a dynamic fixator, combined with a bone graft in 58% of the patients, contributed to a 98% success rate. Proper timing of dynamization is emphasized to avoid angulation, nonunion, or delayed union.


Assuntos
Fixação de Fratura/instrumentação , Fraturas Expostas/terapia , Fraturas da Tíbia/terapia , Adolescente , Adulto , Idoso , Criança , Desenho de Equipamento , Feminino , Fixação de Fratura/efeitos adversos , Fixação de Fratura/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Dispositivos de Fixação Ortopédica/efeitos adversos , Fatores de Tempo , Cicatrização
17.
Am J Ment Defic ; 83(4): 385-90, 1979 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-420262

RESUMO

Forty-four mentally retarded individuals were studied to determine if relocation syndrome can be averted in interinstitutional transfer. Twenty-two persons who were transferred on a voluntary basis to a small, new, highly staffed facility and given individualized attention in preparation for the move were compared to a group of nontransferred matched control persons on the Progress Assessment Chart and the Maladaptive section of the Adaptive Behavior Scale, Which were administered prior to transfer and 1, 2, and 4 weeks after. The transferred group displayed no lowered functioning in adaptive behavior and no increase in maladaptive behavior. No relocation syndrome was evidenced as prerelocation preparation appears to have averted the deleterious effects of transfer.


Assuntos
Institucionalização , Deficiência Intelectual/psicologia , Participação do Paciente , Estresse Psicológico/prevenção & controle , Adolescente , Adulto , Atenção , Família , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ajustamento Social , Comportamento Social , Meio Social
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