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1.
Sci Rep ; 7(1): 14273, 2017 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-29079845

RESUMO

An important goal of vaccination against viruses and virus-driven cancers is to elicit cytotoxic CD8+ T cells specific for virus-derived peptides. CD8+ T cell responses can be enhanced by engaging help from natural killer T (NKT) cells. We have produced synthetic vaccines that induce strong peptide-specific CD8+ T cell responses in vivo by incorporating an NKT cell-activating glycolipid. Here we examine the effect of a glycolipid-peptide conjugate vaccine incorporating an NKT cell-activating glycolipid linked to an MHC class I-restricted peptide from a viral antigen in human peripheral blood mononuclear cells. The vaccine induces CD1d-dependent activation of human NKT cells following enzymatic cleavage, activates human dendritic cells in an NKT-cell dependent manner, and generates a pool of activated antigen-specific CD8+ T cells with cytotoxic potential. Compared to unconjugated peptide, the vaccine upregulates expression of genes encoding interferon-γ, CD137 and granzyme B. A similar vaccine incorporating a peptide from the clinically-relevant human papilloma virus (HPV) 16 E7 oncoprotein induces cytotoxicity against peptide-expressing targets in vivo, and elicits a better antitumor response in a model of E7-expressing lung cancer than its unconjugated components. Glycolipid-peptide conjugate vaccines may prove useful for the prevention or treatment of viral infections and tumors that express viral antigens.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Glicolipídeos/química , Proteínas Oncogênicas Virais/imunologia , Vacinas de Subunidades Antigênicas/química , Vacinas de Subunidades Antigênicas/imunologia , Animais , Humanos , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/virologia , Ativação Linfocitária/imunologia , Camundongos
3.
Biochem Soc Trans ; 34(Pt 4): 581-2, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16856866

RESUMO

The maintenance of telomere length is important in upholding the integrity of the genome. However, it is clear from detailed observations of both telomere length and internal repeat structure that human telomeres are extremely dynamic structures and are subjected to multiple processes that create considerable heterogeneity. Genetic evidence suggests that meiotic recombination within telomeres is rare. However, there are various lines of evidence that implicate the involvement of intra-allelic processes in human telomere dynamics. In this paper, we briefly review some of this evidence and the putative mechanisms of intra-allelic telomeric mutation.


Assuntos
Alelos , Telômero/genética , Cromossomos Humanos/genética , Humanos , Mutação/genética , Recombinação Genética/genética
4.
J Adolesc Health ; 29(3): 156-9, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11524213

RESUMO

PURPOSE: To improve physicians' discussions of confidentiality policies with adolescent patients. METHOD: Fifty-three students completed private semistructured interviews designed to explore adolescents' interpretations of a statement explaining both the protections and limitations of confidentiality. RESULTS: Results suggest strategies for explaining conditional confidentiality in a way adolescents' understand and trust.


Assuntos
Medicina do Adolescente , Confidencialidade , Relações Médico-Paciente , Garantia da Qualidade dos Cuidados de Saúde/legislação & jurisprudência , Adolescente , Confidencialidade/legislação & jurisprudência , Coleta de Dados , Feminino , Humanos , Masculino , Defesa do Paciente , Estados Unidos
5.
J Chromatogr A ; 909(2): 111-35, 2001 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-11269513

RESUMO

The quality of sample preparation is a key factor in determining the success of analysis. While analysis of pharmaceutically important compounds in biological matrixes has driven forward the development of sample clean-up procedures in last 20 years, today's chemists face an additional challenge: sample preparation and analysis of complex biochemical samples for characterization of genotypic or phenotypic information contained in DNA and proteins. This review focuses on various sample pretreatment methods designed to meet the requirements for the analysis of biopolymers and small drugs in complex matrices. We discuss the advances in development of solid-phase extraction (SPE) sorbents, on-line SPE, membrane-based sample preparation, and sample clean-up of biopolymers prior to their analysis by mass spectrometry.


Assuntos
Cromatografia/métodos , Espectrometria de Massas/métodos , DNA/isolamento & purificação , Eletroquímica , Peptídeos/isolamento & purificação , Proteínas/isolamento & purificação
6.
Percept Psychophys ; 61(7): 1320-35, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10572461

RESUMO

The reliability of subjects' judgments of the groups present in dot patterns and the sensitivity of those judgments to stimulus transformation were assessed. The subjects indicated the groups that they saw within random dot patterns, and each judgment was compared with those of other subjects and with their own judgments for related presentations. Within subjects, each pattern appeared in an initial presentation, an identical repetition, and a transformed state (a rotation or a change in scale). Within-subjects judgments were more reliable than between-subjects judgments. An interpretation of within-subjects results was made in relation to predictions made by a formal algorithm of grouping by proximity (the CODE algorithm), which assumes that grouping by proximity is invariant over transformations such as rotations or changes in scale. A slight cost to transforming the patterns was found. The implications for CODE and for using grouping judgments as data are discussed.


Assuntos
Julgamento , Reconhecimento Visual de Modelos/fisiologia , Humanos , Estimulação Luminosa , Reprodutibilidade dos Testes , Rotação , Sensibilidade e Especificidade
7.
J Exp Psychol Hum Percept Perform ; 22(1): 159-72, 1996 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8742259

RESUMO

Theories of the apprehension of spatial relations differ in the predictions they make about the effects of distance between the arguments of spatial relations and the effects of distracting stimuli presented along with the arguments. One theory predicts no effect of distance, another predicts a monotonic increase in reaction time (RT) with distance, and a third predicts a monotonic decrease. Most theories predict slower RTs but reasonable accuracy when distractors are present, but 1 theory predicts chance-level accuracy. These predictions were tested in 3 sentence-picture comparison experiments, in which subjects searched for targets exemplifying the relations above and below. Distance had no effect when no distractors were present. Distractors slowed RT but did not reduce accuracy to chance levels. These results suggest modifications to many of the theories of apprehension.


Assuntos
Percepção Espacial , Humanos , Idioma , Tempo de Reação
9.
Talanta ; 40(12): 1943-50, 1993 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18965874

RESUMO

This paper evaluates the feasibility of two systems-the Sequential Injection (SI) analyzer and the Zymark Benchmate (ZB) robot-for the automation of a recombinant human Factor Thirteen (rhFXIII) fluorometric assay. The goal was to develop a routine analytical procedure suitable for the quality control lab environment. The experimental efforts focused on monitoring of the product formation for the condensation reaction between monodansyl cadaverin and dimethyl casein. The acquired kinetic data demonstrated that both systems are capable of automating the solution handling operations associated with the assay. Using a method developed with the SI system, samples containing 0-410 mug/ml of rhFXIII were analyzed, with a throughput of one sample per 8 min, and a total solution consumption of 0.8 ml. The relative standard deviation for 10 injections of 100 mug/ml rhFXIII sample was 0.91%. With the ZB robot, samples containing 0-2500 mug/ml of rhFXIII were analyzed, and the linear response was obtained for a concentration range between 0 and 1250 mug/ml of rhFXIII. The method had a sample throughput of one sample per 11 min and a total solution consumption of 6.3 ml for each analysis. Due to its commercial availability, the ZB system was preferred over the experimental SI system for the purpose of routine automated analysis of a large number of samples in the quality control lab environment.

11.
Percept Psychophys ; 53(4): 403-21, 1993 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8483704

RESUMO

A formal approach to the phenomenon of perceptual grouping by proximity was investigated. Grouping judgments of random dot patterns were made by the CODE algorithm (van Oeffelen & Vos, 1982) and several related algorithms, and these judgments were compared with subjects' grouping judgments for the same stimuli. Each algorithm predicted significantly more subject judgments than would be expected by chance. The more subjects agreed on how a given dot pattern should be grouped, the more successful was the algorithms' ability to match the judgments for that pattern. CODE predicted significantly fewer subject judgments than did some of the other algorithms, largely because of its overemphasis on the extent of interactivity among dots as they are being grouped.


Assuntos
Algoritmos , Percepção Visual/fisiologia , Adulto , Percepção de Distância , Feminino , Humanos , Masculino , Estimulação Luminosa
12.
J Ind Microbiol ; 11(1): 7-12, 1992 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-1369016

RESUMO

Supplementing the culture of Micromonospora chersina sp. nov. No. M956-1 with NaI (0.5 mg/l) enhanced the production of dynemicin A by 35-fold in shake flask culture. Homogeneous dynemicin A was obtained from the whole broth extract by Dicalite chromatography, Sephadex LH-20 chromatography and vacuum liquid chromatography. Gram quantities of dynemicin A were obtained from the fermentation of M. chersina sp. nov. No. M956-1 in a 10,000-liter fermentor.


Assuntos
Antibióticos Antineoplásicos/biossíntese , Meios de Cultura , Fermentação , Antraquinonas/isolamento & purificação , Antraquinonas/metabolismo , Antibióticos Antineoplásicos/isolamento & purificação , Enedi-Inos , Micromonospora/metabolismo
13.
Anal Chem ; 63(22): 2597-602, 1991 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-1776698

RESUMO

The free zone electrophoretic mobility of proteins can be predicted from the protein's amino acid content by applying a model based on the Debye-Hückle-Henry theory and Henderson-Hasselbalch equation. Calculated mobilities are always greater than actual mobility but a pH-independent proportionality (described by the constant FZ) is found between the two. Thus, determination of a protein's mobility at one pH allows, with the use of the model and FZ, calculation of its mobility at other pH conditions. This leads directly to optimum conditions for the electrophoretic resolution of proteins in capillary zone electrophoresis. The fundamental nature of FZ is examined and found to be a function of a proteins molecular weight, charge, and solution ionic strength. This work aids in explaining the form of previously proposed empirically based equations for peptide and protein mobility.


Assuntos
Proteínas/química , Eletroquímica , Eletroforese
14.
J Wildl Dis ; 27(4): 716-8, 1991 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-1758042

RESUMO

During the fall hunting season of 1990, 95 white-tailed deer (Odocoileus virginianus) heads were collected from hunters in Boundary and Bonner Counties in northern Idaho (USA), an area currently occupied by woodland caribou (Rangifer tarandus caribou). The heads were examined for adult and larval meningeal worms (Parelaphostrongylus tenuis) by physical examination of the brain surfaces, and the Baermann technique, respectively, and for ear mites by examination of ear scrapings. Meningeal worms or mites were not detected.


Assuntos
Cervos/parasitologia , Metastrongyloidea/isolamento & purificação , Infestações por Ácaros/veterinária , Infecções por Nematoides/veterinária , Animais , Encéfalo/parasitologia , Meato Acústico Externo/parasitologia , Feminino , Idaho/epidemiologia , Larva/isolamento & purificação , Masculino , Infestações por Ácaros/epidemiologia , Ácaros/isolamento & purificação , Infecções por Nematoides/epidemiologia
15.
Mem Cognit ; 19(2): 151-8, 1991 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-2017038

RESUMO

Two memory-based theories of automaticity were compared. The mixture model and the race model both describe automatization as a transition from algorithmic processing to memory retrieval. The mixture model predicts that, with training, the variability of reaction time will initially increase, and later decrease in a concave downward manner, whereas the race model predicts the variability will decrease only in a concave upward manner. The mixture model predicts that using both algorithm and retrieval on a single trial will be slower than using the algorithm alone, whereas the race model predicts the reverse. The experiments used an alphabet arithmetic task, in which subjects verified equations of the form H + 3 = K and made subjective reports of their strategies on individual trials. Both the variability of reaction times and the pattern of reaction times associated with the strategy reports supported the race model.


Assuntos
Cognição , Memória , Modelos Psicológicos , Algoritmos , Humanos , Matemática , Resolução de Problemas , Tempo de Reação
17.
Anal Chem ; 61(13): 1314-7, 1989 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-2774191

RESUMO

Protein A based rapid affinity chromatography for quantitation of various immunoglobulins of class G (IgG) is described. Three-minute analysis using either citrate or phosphate buffers and detection with 220- or 280-nm ultraviolet absorption was found to be optimum for quantitation of IgG from 0.25 to 250 micrograms of IgG on-column with a percent relative standard deviation (% RSD) of 2-3% RSD. The method has a detection limit estimated to be 100 ng of IgG on-column. It has been used to analyze a variety of IgG-containing samples from such diverse sources as hybridoma selection, media cultivation, and purification studies. Gradient elution studies and the relationship of IgG elution to IgG isoelectric point (pI) are also described.


Assuntos
Anticorpos Monoclonais/análise , Proteína Estafilocócica A , Animais , Bovinos , Cromatografia de Afinidade , Humanos , Concentração de Íons de Hidrogênio , Imunoglobulina G/análise , Camundongos
18.
Med Educ ; 22(1): 60-6, 1988 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-3357448

RESUMO

Empirical comparisons of priorities of consumers and educators in university-based programmes in psychiatry, psychiatric nursing and social work are described. Data resulted from a Q-sort of 200 objectives for mental health education. The results of the tests of validity and reliability of the instrument are described, followed by a discussion of the similarities and differences among the four samples of subjects: consumers and educators in the three mental health professions. Suggestions for applications of this methodology by inter- and intradisciplinary service providers are described.


Assuntos
Comportamento do Consumidor , Docentes , Psiquiatria/educação , Atitude do Pessoal de Saúde , Humanos , Minnesota , Enfermagem Psiquiátrica/educação , Serviço Social em Psiquiatria/educação
19.
Invest Ophthalmol Vis Sci ; 25(2): 153-9, 1984 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-6698737

RESUMO

It is shown that the technique of sedimentation field-flow fractionation (sedimentation [sed] FFF) can be used to determine the particle content and particle size distribution of normal and cataractous lenses. A 31-year-old normal human lens, for example, showed a particle content of 1.5% by weight with diameters ranging from 0.12 micron to 0.9 micron. The urea insoluble material present in the nuclear and cortical fractions from a densely cataractous lens contained particles ranging from 0.12 micron to 1.7 micron, with average sizes of 0.83 micron and 0.82 micron respectively, for the two fractions. These numbers offer a basis for comparison; their actual values may be shifted slightly either up or down depending on the assessment of particle density. These sizes, which correspond to molecular weights of around 2 X 10(9) dalton, are larger than previously reported for lens particulates. The sed FFF method is thus seen to permit fractionation and size analysis of small amounts of lens material in times less than one hour.


Assuntos
Catarata/metabolismo , Cristalinas/análise , Cristalino/análise , Fracionamento Químico/instrumentação , Fracionamento Químico/métodos , Humanos , Tamanho da Partícula
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