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1.
Br J Dermatol ; 178(6): 1331-1340, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29315488

RESUMEN

BACKGROUND: Incontinence-associated dermatitis (IAD) is a specific type of irritant contact dermatitis with different severity levels. An internationally accepted instrument to assess the severity of IAD in adults, with established diagnostic accuracy, agreement and reliability, is needed to support clinical practice and research. OBJECTIVES: To design the Ghent Global IAD Categorization Tool (GLOBIAD) and evaluate its psychometric properties. METHODS: The design was based on expert consultation using a three-round Delphi procedure with 34 experts from 13 countries. The instrument was tested using IAD photographs, which reflected different severity levels, in a sample of 823 healthcare professionals from 30 countries. Measures for diagnostic accuracy (sensitivity and specificity), agreement, interrater reliability (multirater Fleiss kappa) and intrarater reliability (Cohen's kappa) were assessed. RESULTS: The GLOBIAD consists of two categories based on the presence of persistent redness (category 1) and skin loss (category 2), both of which are subdivided based on the presence of clinical signs of infection. The agreement for differentiating between category 1 and category 2 was 0·86 [95% confidence interval (CI) 0·86-0·87], with a sensitivity of 90% and a specificity of 84%. The overall agreement was 0·55 (95% CI 0·55-0·56). The Fleiss kappa for differentiating between category 1 and category 2 was 0·65 (95% CI 0·65-0·65). The overall Fleiss kappa was 0·41 (95% CI 0·41-0·41). The Cohen's kappa for differentiating between category 1 and category 2 was 0·76 (95% CI 0·75-0·77). The overall Cohen's kappa was 0·61 (95% CI 0·59-0·62). CONCLUSIONS: The development of the GLOBIAD is a major step towards a better systematic assessment of IAD in clinical practice and research worldwide. However, further validation is needed.


Asunto(s)
Dermatitis Irritante/etiología , Lenguaje , Índice de Severidad de la Enfermedad , Incontinencia Urinaria/complicaciones , Adulto , Dermatitis Irritante/diagnóstico , Femenino , Humanos , Internacionalidad , Masculino , Variaciones Dependientes del Observador , Psicometría , Estándares de Referencia , Sensibilidad y Especificidad , Terminología como Asunto
2.
Clin Exp Immunol ; 185(3): 372-81, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-27218304

RESUMEN

Recently, there has been considerable interest in using 4-methylumbelliferone (4-MU) to inhibit hyaluronan (HA) synthesis in mouse models of cancer, autoimmunity and a variety of other inflammatory disorders where HA has been implicated in disease pathogenesis. In order to facilitate future studies in this area, we have examined the dosing, treatment route, treatment duration and metabolism of 4-MU in both C57BL/6 and BALB/c mice. Mice fed chow containing 5% 4-MU, a dose calculated to deliver 250 mg/mouse/day, initially lose substantial weight but typically resume normal weight gain after 1 week. It also takes up to a week to see a reduction in serum HA in these animals, indicating that at least a 1-week loading period on the drug is required for most protocols. At steady state, more than 90% of the drug is present in plasma as the glucuronidated metabolite 4-methylumbelliferyl glucuronide (4-MUG), with the sulphated metabolite, 4-methylumbelliferyl sulphate (4-MUS) comprising most of the remainder. Chow containing 5% but not 0·65% 4-MU was effective at preventing disease in the experimental autoimmune encephalomyelitis (EAE) mouse model of multiple sclerosis, as well as in the DORmO mouse model of autoimmune diabetes. While oral 4-MU was effective at preventing EAE, daily intraperitoneal injections of 4-MU were not. Factors potentially affecting 4-MU uptake and plasma concentrations in mice include its taste, short half-life and low bioavailability. These studies provide a practical resource for implementing oral 4-MU treatment protocols in mice.


Asunto(s)
Encefalomielitis Autoinmune Experimental/tratamiento farmacológico , Ácido Hialurónico/antagonistas & inhibidores , Ácido Hialurónico/biosíntesis , Himecromona/administración & dosificación , Himecromona/farmacocinética , Administración Oral , Animales , Disponibilidad Biológica , Modelos Animales de Enfermedad , Encefalomielitis Autoinmune Experimental/inducido químicamente , Encefalomielitis Autoinmune Experimental/inmunología , Encefalomielitis Autoinmune Experimental/prevención & control , Semivida , Ácido Hialurónico/sangre , Himecromona/sangre , Himecromona/metabolismo , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL
3.
Skin Pharmacol Physiol ; 23(4): 201-12, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20215813

RESUMEN

In the past, several attempts have been made to develop in vitro methods for determining protection against UV radiation. To date however, there is no broadly accepted method. Various known and unknown parameters influence the transmission measurements of scattering films, such as the multifaceted compositions of sunscreens, the technical limitations of measurement devices as well as the difficulty to apply very thin films of sunscreen in a reproducible manner throughout different laboratories. In vitro data were measured in this multicenter study to compare possible methodologies and strategies for an in vitro approach to the sun protection factor (SPF). This publication will not present a final in vitro SPF test method, but it will point out which technical side effects may influence such a method. Influential factors such as the quality of spectrophotometer used, the amount of product applied, pretreatment of samples, time and temperature of equilibration, size of the measured surface, the application process or the calculation on the basis of standardized data are presented and discussed. Finally, a reduction of the standard deviations within single laboratories could be realized for in vitro SPF testing, but no improvement of the interlaboratory comparison was obtained. The development of a valid and reliable SPF in vitro test still remains a challenge, and further work is necessary to develop a satisfactory method.


Asunto(s)
Ensayo de Materiales/normas , Luz Solar/efectos adversos , Protectores Solares/química , Administración Cutánea , Humanos , Técnicas In Vitro , Ensayo de Materiales/métodos , Espectrofotometría Ultravioleta/métodos , Espectrofotometría Ultravioleta/normas , Protectores Solares/administración & dosificación , Rayos Ultravioleta/efectos adversos
4.
Oncogene ; 26(31): 4489-98, 2007 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-17297467

RESUMEN

The Hedgehog pathway transcription factor Gli1 induces transformation of epithelial cells via induction of Snail, a repressor of E-cadherin (E-cad). E-cad is normally complexed with beta-catenin at the cell membrane. Loss of E-cad during developmental epithelial-mesenchymal transitions can switch beta-catenin from its role at adherens junctions to its role in nuclear transcription. During tumorigenesis it is unclear which pathways trigger this switch. In the current study, gain- and loss-of-function approaches identified E-cad as a selective inhibitor of transformation by Gli1, and Snail knockdown was rescued by downregulation of E-cad. Gli1 induced relocalization of beta-catenin from the cell membrane to the nucleus. The ability of wild-type or mutant alleles of E-cad to modulate transformation by Gli1 correlated with their ability to regulate localization of beta-catenin. Inhibition of Wnt-beta-catenin signaling by dominant negative Tcf4 selectively blocked in vitro transformation by Gli1. In Gli1-transgenic mice, infiltrating skin tumor cells expressed active, unphosphorylated beta-catenin. Our studies identify E-cad as a selective suppressor of transformation by Gli1 and point to the Sonic Hedgehog-Gli1 pathway as a key regulator of the beta-catenin switch in epithelial cells and cancers.


Asunto(s)
Cadherinas/metabolismo , Factores de Transcripción de Tipo Kruppel/metabolismo , Factores de Transcripción/metabolismo , beta Catenina/metabolismo , Animales , Núcleo Celular/metabolismo , Transformación Celular Neoplásica/metabolismo , Células Cultivadas , Proteínas de Unión al ADN/farmacología , Células Epiteliales , Riñón , Ratones , Ratones Transgénicos , Ratas , Transducción de Señal , Factores de Transcripción de la Familia Snail , Factor de Transcripción 4 , Factores de Transcripción/farmacología , Proteínas Wnt/metabolismo , Proteína con Dedos de Zinc GLI1
5.
Oncogene ; 25(4): 609-21, 2006 Jan 26.
Artículo en Inglés | MEDLINE | ID: mdl-16158046

RESUMEN

Gli family members mediate constitutive Hedgehog signaling in the common skin cancer, basal cell carcinoma (BCC). Snail/Snai1 is rapidly induced by Gli1 in vitro, and is coexpressed with Gli1 in human hair follicles and skin tumors. In the current study, we generated a dominant-negative allele of Snail, SnaZFD, composed of the zinc-finger domain and flanking sequence. In promoter-reporter assays, SnaZFD blocked the activity of wild-type Snail on the E-cadherin promoter. Snail loss-of-function mediated by SnaZFD or by one of several short hairpin RNAs inhibited transformation of RK3E epithelial cells by Gli1. Conversely, enforced expression of Snail promoted transformation in vitro by Gli1, but not by other genes that were tested, including Notch1, ErbB2, and N-Ras. As observed for Gli1, wild-type Snail repressed E-cadherin in RK3E cells and induced blebbing of the cytoplasmic membrane. Induction of a conditional Gli1 transgene in the basal keratinocytes of mouse skin led to rapid upregulation of Snail transcripts and to cell proliferation in the interfollicular epidermis. Established Gli1-induced skin lesions exhibited molecular similarities to BCC, including loss of E-cadherin. The results identify Snail as a Gli1-inducible effector of transformation in vitro, and an early Gli1-responsive gene in the skin.


Asunto(s)
Transformación Celular Neoplásica , Factores de Transcripción de Tipo Kruppel/fisiología , Factores de Transcripción/fisiología , Animales , Secuencia de Bases , Carcinoma Basocelular/etiología , Ciclo Celular , Hiperplasia , Ratones , Ratones Endogámicos C57BL , Datos de Secuencia Molecular , ARN Interferente Pequeño/farmacología , Piel/patología , Neoplasias Cutáneas/etiología , Factores de Transcripción de la Familia Snail , Factores de Transcripción/genética , Proteína con Dedos de Zinc GLI1
6.
Curr Biol ; 6(6): 750-2, 1996 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-8793301

RESUMEN

A new member of the tumor necrosis factor (TNF) cytokine family, designated Apo-2 ligand (Apo-21) [1] or TRAIL [2], has been shown recently to induce apoptosis in various tumor cell lines; however, its biological role is unknown. Here, we show that Apo-21, activated apoptosis in T-cell-enriched cultures of peripheral blood lymphocytes stimulated by interleukin-2 (IL-2), but not in unstimulated cells. This finding suggests that, like Fas/Apo-1 ligand and TNF [3-5], Apo-2L may play a role in regulating post-stimulation apoptosis of mature lymphocytes. Studies on the mechanism of Apo-2L action demonstrated marked membrane blebbing, a hallmark of apoptosis, within a few minutes of the addition of Apo-2L to tumor cells. Ectopic expression of a dominant negative mutant of FADD, a cytoplasmic protein that mediates death signalling by Fas/Apo-1 and by TNF receptor type 1 (TNFR1) [6-9], inhibited the induction of apoptosis by anti-Fas/Apo-1 antibody, but had little effect on Apo-2L function. In contrast, expression of CrmA, a cowpox virus-derived inhibitor of the Ced-2-like proteases ICE [10] and CPP32/Yama [11,12], blocked the induction of apoptosis by either Apo-2L or anti-Fas/Apo-1 antibody. These results suggest that Apo-2L activates a rapid, FADD-independent pathway to trigger a cell-death programme that requires the function of cysteine proteases such as ICE or CPP32/Yama.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales , Apoptosis , Proteínas Portadoras/metabolismo , Glicoproteínas de Membrana/farmacología , Serpinas/metabolismo , Linfocitos T/efectos de los fármacos , Factor de Necrosis Tumoral alfa/farmacología , Proteínas Virales , Proteínas Reguladoras de la Apoptosis , Células Cultivadas , Proteína de Dominio de Muerte Asociada a Fas , Humanos , Interleucina-2/farmacología , Linfocitos T/citología , Ligando Inductor de Apoptosis Relacionado con TNF
7.
Nucleic Acids Res ; 29(10): 2003-11, 2001 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-11353068

RESUMEN

As compared to the metazoan small nuclear RNAs (snRNAs), relatively little is known about snRNA synthesis in unicellular organisms. We have analyzed the transcription of the Schizosaccharomyces pombe U2 snRNA gene in vivo and in the homologous in vitro system. Deletion and linker-scanning analyses show that the S.pombe U2 promoter contains at least two elements: the spUSE centered at -55, which functions as an activator, and a TATA box at -26, which is essential for basal transcription. These data point to a similar architecture among S.pombe, plant and invertebrate snRNA promoters. Factors recognizing the spUSE can be detected in whole cell extracts by DNase I footprinting and competition studies show that the binding of these factors correlates with transcriptional activity. Electrophoretic mobility shift assays and gel-filtration chromatography revealed a native molecular mass of approximately 200 kDa for the spUSE binding activity. Two polypeptides of molecular masses 25 and 65 kDa were purified by virtue of their ability to specifically bind the spUSE.


Asunto(s)
Elementos de Respuesta/genética , Schizosaccharomyces/genética , TATA Box/genética , Transcripción Genética/genética , Unión Competitiva , Cromatografía en Gel , Huella de ADN , Sondas de ADN/genética , Sondas de ADN/metabolismo , Proteínas de Unión al ADN/química , Proteínas de Unión al ADN/aislamiento & purificación , Proteínas de Unión al ADN/metabolismo , Desoxirribonucleasa I/metabolismo , Peso Molecular , Ensayos de Protección de Nucleasas , ARN Nuclear Pequeño/genética , Eliminación de Secuencia , Factores de Transcripción/química , Factores de Transcripción/aislamiento & purificación , Factores de Transcripción/metabolismo , Activación Transcripcional
8.
Oncogene ; 15(4): 385-92, 1997 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-9242374

RESUMEN

The retinoblastoma tumor suppressor gene product (Rb) binds directly to the largest TFIID subunit, TATA-binding protein associated factor TAF(II)250, first identified as the cell cycle regulatory protein CCG1. Here we map the domains in Rb and TAF(II)250 important for their interaction in vitro and in vivo. Both the amino terminus and the large pocket of Rb are able to associate independently with TAF(II)250. The binding domain(s) within the large pocket are distinct from the viral oncoprotein and E2F binding region since certain pocket mutations, which abolish E1A binding, do not abolish TAF(II)250 binding. Consistent with the large pocket of Rb binding to TAF(II)250, the large pocket domains of both p107 and p130 are able to bind to TAF(II)250 in vivo. We also demonstrate that at least two regions of TAF(II)250 are able to bind to the large pocket of Rb independently whereas the amino terminus of Rb binds to a distinct domain in TAF(II)250. We further demonstrate that Rb can bind to TFIID in vitro, presumably in part through an interaction with TAF(II)250. Our results suggest a complex interaction between Rb and TAF(II)250 and imply that TAF(II)250, TFIID, and potentially other basal transcription factors are targets for regulation by Rb and Rb-related proteins.


Asunto(s)
Proteína de Retinoblastoma/metabolismo , Factores de Transcripción TFII/metabolismo , Sitios de Unión , Células HeLa , Humanos , Factor de Transcripción TFIID
9.
J Mol Biol ; 184(3): 367-73, 1985 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-2413215

RESUMEN

The tyrosine aminotransferase (TAT) gene is expressed in a tissue and developmental-specific manner. In addition, this gene is regulated by glucocorticoid and polypeptide hormones and its expression is affected when a regulatory region near the albino locus of the mouse is deleted. In order to allow studies of the molecular effects of these deletion mutations we have isolated and characterized the mouse TAT gene. The gene is 9.2 x 10(3) bases in length and consists of 12 exons which give rise to a 2.3 x 10(3) base long messenger RNA. The DNA sequence at the 5' end of the gene was determined and compared with the corresponding sequence of the rat tyrosine aminotransferase gene. The sequence comparison showed extensive homology over the entire region sequenced. In addition, DNA: DNA heteroduplex studies between the mouse and rat tyrosine aminotransferase genes revealed that this homology extends over the entire gene and its flanking sequences. The mouse tyrosine aminotransferase gene has been mapped distal to the serum esterase-1 locus on mouse chromosome 8, using a restriction fragment length polymorphism between two mouse species. Since the albino deletions are located on mouse chromosome 7, the assignment of the TAT gene to chromosome 8 suggests that a regulatory factor(s) affecting TAT gene expression acts in trans.


Asunto(s)
Mapeo Cromosómico , Genes , Tirosina Transaminasa/genética , Animales , Secuencia de Bases , ADN/genética , Ratones , Microscopía Electrónica , Hibridación de Ácido Nucleico , ARN/genética , Ratas
10.
Genetics ; 129(3): 825-32, 1991 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-1684331

RESUMEN

Previous complementation analyses with five (c11DSD, c5FR60Hg, c2YPSj, c4FR60Hd, c6H) of the mouse albino deletions defined at least two genes on chromosome 7, known as eed and exed, which are necessary for development of the embryonic and extraembryonic ectoderm, respectively, of early postimplantation embryos. The region of chromosome 7 containing these two genes has now been accessed at the molecular level by cloning two of the deletion breakpoint-fusion fragments. The c2YPSj breakpoints were isolated by cloning an EcoRI fragment containing a copy of an albino region-specific repeat unique to c2YPSj DNA. Similarly, the c11DSD breakpoints were isolated by cloning a c11DSD EcoRI fragment detected by a unique-sequence probe mapping proximal to the albino-coat-color locus. By mapping the cloned breakpoints relative to the remaining three deletions, the c11DSD distal breakpoint was found to define the distal limit of the region containing eed, whereas the c2YPSj and c6H distal breakpoints were found to define the proximal and distal limits, respectively, of the region containing exed.


Asunto(s)
Albinismo/genética , Ratones/genética , Animales , Deleción Cromosómica , Mapeo Cromosómico , Clonación Molecular , Ectodermo/fisiología , Ratones/embriología , Polimorfismo de Longitud del Fragmento de Restricción
11.
Exp Hematol ; 11(2): 154-61, 1983 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-6601024

RESUMEN

A medium conditioned by leukocytes in the presence of phytohemagglutinin (PHA-LCM) promotes the growth of human multilineage hemopoietic progenitors CFUGEMM which form mixed hemopoietic colonies in culture containing granulocytes, erythroblasts, megakaryocytes, macrophages and mononuclear cells with T-cell antigens. In addition PHA-LCM supports the growth of erythroid bursts (BFUE) and granulocytic colonies (CFUC). Stimulatory activities of PHA-LCM were characterized by gel filtration using Sephacryl S 300. The eluted growth promoting activities were rechromatographed on Sepharose 4 B covalently linked with Lentil Lectin. The stimulatory activities for noncommitted precursors CFUGEMM, and committed progenitors BFUE, and CFUC were detected in the unretained material i.e. the activities revealed no affinity to Lentil-Lectin. The apparent molecular weight of these stimulatory molecules ranged from 35,000-45,000, as determined by SDS gel electrophoresis (PAGE).


Asunto(s)
Células de la Médula Ósea , Ensayo de Unidades Formadoras de Colonias , Factores Estimulantes de Colonias/análisis , Células Madre Hematopoyéticas/citología , Cromatografía de Afinidad , Cromatografía en Gel , Medios de Cultivo , Eritroblastos/citología , Granulocitos/citología , Humanos , Macrófagos/citología , Megacariocitos/citología , Peso Molecular , Linfocitos T/citología
12.
Eur J Cell Biol ; 59(1): 80-91, 1992 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-1361433

RESUMEN

The permanent cell culture line AR42J, derived from a rat pancreatic acinar carcinoma, is widely used for functional studies of exocrine pancreatic acinar cells. We now present evidence that these cells are amphicrine in that they contain zymogen granules as well as small (40-80 nm) neuroendocrine (NE) vesicles and typical neurotransmitters. Using the small NE vesicle-specific markers synaptophysin and "protein S.V.2", including synaptophysin cDNA probes, we have found that AR42J cells synthesize these proteins and contain vesicles harboring these proteins with biophysical properties similar to those of small NE vesicles. NE properties of these cells are further indicated by the presence of considerable amounts of stored amino acids (gamma-aminobutyric acid (GABA), glycine, glutamate) and by the presence of the GABA-synthesizing enzyme, glutamic acid decarboxylase. Finally, intermediate filament (IF) protein typing showed only cytokeratins 8 and 18, indicating that AR42J cells possess an IF protein complement indistinguishable from that of acinar and islet cells. Our results document the unusual case of a permanent cell line with combined exocrine and neuroendocrine properties that may be indicative of a derivation from a cell with multipotential character.


Asunto(s)
Precursores Enzimáticos/metabolismo , Glicoproteínas de Membrana/metabolismo , Proteínas del Tejido Nervioso/metabolismo , Páncreas/metabolismo , Sinaptofisina/metabolismo , Animales , Línea Celular/metabolismo , Línea Celular/ultraestructura , Glutamato Descarboxilasa/biosíntesis , Glutamatos/biosíntesis , Ácido Glutámico , Glicina/biosíntesis , Inmunohistoquímica , Ratas , Ácido gamma-Aminobutírico/biosíntesis
13.
Biotechnol Prog ; 17(1): 182-7, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11170497

RESUMEN

A correlation between the osmotic second virial coefficient and the solubility of proteins is derived from classical thermodynamics to support an empirical relation previously found by Wilson and co-workers (1). The model is based on the equality of fugacities of the protein in the equilibrium phases, with the details of the model depending on the standard state used. The parameters in this model have been fitted to data for several systems, mainly with lysozyme as the protein. The model is found to describe experimental data, with variations in protein concentration, salt type and concentration, temperature, and pH, both qualitatively and quantitatively. Agreement between the model and the experimental data is very good for protein solubilities up to 30 mg/mL. Above this value the model underpredicts the experimental data, probably as a result of multibody interactions that are not included in the model here. Variations of the model parameters with protein type, temperature, pH, and salt type are discussed.


Asunto(s)
Proteínas/química , Concentración de Iones de Hidrógeno , Modelos Químicos , Muramidasa/química , Ósmosis , Ovalbúmina/química , Sales (Química) , Solubilidad , Temperatura , Termodinámica
14.
Physiol Res ; 43(2): 75-81, 1994.
Artículo en Inglés | MEDLINE | ID: mdl-7918342

RESUMEN

An attempt was made to assess whether the choice of the gradient media could influence the yield of basolateral membrane vesicles isolated from the rat intestine as well as their functional characteristics. Crude membranes prepared in the same way were therefore centrifuged with 10% Percoll, on a discontinuous sucrose gradient or on a continuous sorbitol gradient. The protein yield was significantly higher with the Percoll gradient than with sucrose and sorbitol gradient centrifugation (2.7 +/- 1.0%; 0.4 +/- 0.1%; 0.6 +/- 0.2%, respectively). Enrichment in Na+,K+-ATPase was similar in all three preparations (8.50 +/- 2.34; 8.22 +/- 4.78; 8.20 +/- 2.08). However, contamination with brush border membranes was significantly higher after Percoll gradient centrifugation and negligible after the use of the other two gradient media. Transport of D-glucose in the BLM prepared by Percoll gradient centrifugation also indicated some contamination with functional brush-border membranes. An attempt to purify basolateral membrane vesicles after Percoll gradient centrifugation with Ca2+ precipitation, however, reduced the protein yield to less than 1%. We conclude that in the preparation of basolateral membrane vesicles from the rat enterocytes each of the gradient media may have certain advantages and disadvantages, which should be considered according to the purpose of the preparation.


Asunto(s)
Membrana Celular , Centrifugación por Gradiente de Densidad/métodos , Intestinos/citología , Animales , Fraccionamiento Celular/métodos , Femenino , Glucosa , Intestinos/ultraestructura , Masculino , Povidona , Ratas , Ratas Endogámicas WKY , Dióxido de Silicio , Sorbitol , Sacarosa
15.
J Colloid Interface Sci ; 267(2): 475-82, 2003 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-14583225

RESUMEN

The adsorption kinetics of micellar solutions of anionic/cationic SDS/DATB mixtures with mixing ratios of 10/1 and 10/2, respectively, are studied experimentally by means of the maximum bubble pressure method. For long adsorption times the adsorption of the highly surface-active anionic/cationic complex leads to a decrease of dynamic surface tension in comparison to the single SDS system. However, the situation is the reverse for short adsorption times where the dynamic surface tension is increased by addition of the cationic surfactant, although the overall concentration is increased. This unexpected behavior is explained by partial solubilization of free SDS molecules into micelles formed by SDS/DTAB complexes. With increasing overall concentration, when eventually the CMC of SDS is reached, the anionic/cationic complex itself is solubilized by SDS micelles. Finally, no complex micelles, which for their part can solubilize an excess of SDS molecules, are present. Hence, the dynamic properties of the solution are no longer influenced by the depletion of SDS molecules and the mixture tends to behave like a pure SDS solution.

16.
Hybridoma ; 15(1): 55-68, 1996 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-9064287

RESUMEN

The TATA box-binding protein (TBP) is a key transcription factor required for transcription by all three eukaryotic RNA polymerases. It consists of a conserved carboxy-terminal DNA binding domain and a highly divergent amino terminal domain. TBP and different sets of TBP-associated factors (TAFs) constitute at least four multisubunit complexes referred to as SL1, TFIID, TFIIIB, and SNAPC. SL1, TFIID, and TFIIIB are required for transcription by RNA polymerases I, II, and III, respectively, while the SNAP complex is involved in transcription of the small nuclear RNA (snRNA) genes by RNA polymerases II and III. TBP also associates with a number of basal transcription factors such as TFIIA and TFIIB, and with several regulatory factors such as VP16, E1A, and p53. Here we describe the characterization of a panel of monoclonal antibodies (MAbs) directed against the amino-terminal domain of human TBP. These MAbs recognize different TBP epitopes, some of which have been precisely defined. Different MAbs recognize different TBP-containing complexes and several of them crossreact with TBP from other species. These antibodies can be used to purify TBP-containing complexes in a functional form and should be useful to identify new protein-protein interactions involving TBP.


Asunto(s)
Anticuerpos Monoclonales/química , Proteínas de Unión al ADN/inmunología , Mapeo Epitopo , Proteínas del Complejo de Iniciación de Transcripción Pol1 , Factores de Transcripción/inmunología , Secuencia de Aminoácidos , Animales , Secuencia Conservada , Cricetinae , Reacciones Cruzadas , ADN/química , Proteínas de Unión al ADN/química , Proteínas de Unión al ADN/aislamiento & purificación , Drosophila , Electroforesis en Gel de Poliacrilamida , Humanos , Ratones , Ratones Endogámicos BALB C , Datos de Secuencia Molecular , Fragmentos de Péptidos/inmunología , Ratas , Erizos de Mar , Especificidad de la Especie , Proteína de Unión a TATA-Box , Factores de Transcripción/química , Factores de Transcripción/aislamiento & purificación
17.
Nurse Pract ; 21(7): 12, 15-8, 24 Passim, 1996 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-8823785

RESUMEN

Because eye injuries and diseases may potentially result in serious vision impairments, accurate diagnosis and treatment of ophthalmic conditions are imperative. A symptom common to eye impairments is conjunctivitis, or red eye, a commonly seen manifestation in an ambulatory pediatric population. Because conjunctivitis is caused by various etiologies, clinicians must derive a differential diagnosis. This article examines possible causes of conjunctivitis after the neonatal period in this population. Differential diagnosis is dependent on a complete history, distinct physical findings, and use of adjunct diagnostic tests. Treatment, which depends on a sound differential diagnosis, should be targeted according to the cause of the problem.


Asunto(s)
Conjuntivitis/diagnóstico , Niño , Preescolar , Conjuntivitis/etiología , Conjuntivitis/terapia , Conjuntivitis Alérgica/diagnóstico , Conjuntivitis Alérgica/terapia , Conjuntivitis Bacteriana/diagnóstico , Conjuntivitis Bacteriana/tratamiento farmacológico , Conjuntivitis Bacteriana/microbiología , Conjuntivitis Viral/diagnóstico , Conjuntivitis Viral/tratamiento farmacológico , Conjuntivitis Viral/virología , Diagnóstico Diferencial , Cuerpos Extraños en el Ojo/terapia , Femenino , Humanos , Técnicas In Vitro , Lactante
18.
Nurse Pract ; 21(4): 38-42, 44, 47-8, 1996 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-8801491

RESUMEN

Pharyngitis or sore throat is a common result of illness in pediatric and adolescent populations. Sore throat can signal either nonsystemic or systemic disease processes. Clinicians in ambulatory settings are often faced with deriving a differential diagnosis based on this symptom. Prompt and appropriate treatment depends on identification of the underlying causative agent or illness. This article examines common causes of sore throat in the pediatric and adolescent populations. These diagnoses are: (1) group A beta-hemolytic streptococcal pharyngitis; (2) non-group A beta-hemolytic streptococcal bacterial pharyngitis; (3) viral pharyngitis; (4) infectious mononucleosis; and (5) chronic conditions. Less common causes are also considered. Differential diagnosis is dependent on complete and accurate history, distinct physical finding, and interpretation of adjunct diagnostic tests. The value of critical data sources is essential in arriving at a differential diagnosis of pharyngitis. Once a diagnosis is established, an appropriate treatment plan can be initiated.


Asunto(s)
Diagnóstico de Enfermería , Faringitis/etiología , Adolescente , Infecciones Bacterianas/diagnóstico , Infecciones Bacterianas/enfermería , Niño , Preescolar , Diagnóstico Diferencial , Femenino , Humanos , Lactante , Mononucleosis Infecciosa/diagnóstico , Mononucleosis Infecciosa/enfermería , Masculino , Faringitis/diagnóstico , Faringitis/enfermería , Infecciones Estreptocócicas/diagnóstico , Infecciones Estreptocócicas/enfermería , Streptococcus pyogenes , Virosis/diagnóstico , Virosis/enfermería
19.
Immunol Res ; 58(2-3): 186-92, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24614953

RESUMEN

The extracellular matrix polysaccharide hyaluronan (HA) exerts size-dependent effects on leukocyte behavior. Low-molecular weight HA is abundant at sites of active tissue catabolism and promotes inflammation via effects on Toll-like receptor signaling. Conversely, high-molecular weight HA is prevalent in uninjured tissues and is anti-inflammatory. We propose that the ability of high-molecular weight but not low-molecular weight HA to cross-link CD44 functions as a novel form of pattern recognition that recognizes intact tissues and communicates "tissue integrity signals" that promote resolution of local immune responses.


Asunto(s)
Ácido Hialurónico/metabolismo , Inflamación/inmunología , Inflamación/metabolismo , Transducción de Señal , Animales , Matriz Extracelular/metabolismo , Humanos , Receptores de Hialuranos/metabolismo , Ácido Hialurónico/química , Peso Molecular , Unión Proteica , Receptores de Reconocimiento de Patrones/metabolismo
20.
Orthopade ; 36(4): 365-71, 2007 Apr.
Artículo en Alemán | MEDLINE | ID: mdl-17262180

RESUMEN

BACKGROUND: Proper timing of stabilization for spinal injuries is discussed controversially. Whereas early repair of long bone fractures is known to reduce complications, few studies exist that investigate this issue in acute spinal trauma. In particular, the importance of coexisting lung injuries has to be determined, as it might influence clinical course and outcome. MATERIAL AND METHODS: We investigated retrospectively 30 severely injured patients who were stabilized dorsally for fractures of the thoracic and upper lumbar spine. The mean Injury Severity Score (ISS) was 41 points. Patients were divided into two groups: group I: acute trauma/stabilization <72 h and group II: acute trauma/stabilization >72 h. All patients in groups I and II presented radiological or clinical signs of lung contusion. RESULTS: The average duration of the procedures in group I was 199 min (115-312 min) and in group II 139 min (98-269 min). Intraoperative blood loss and P(a)O(2)/F(i)O(2)-ratio did not differ significantly between the two groups. The overall in ICU and hospital stay was significantly shorter in group I: 16 days (1-78 days) versus 24 days (7-86 days) in the late group II. Postoperative respirator therapy was necessary in group I for 15 days (0-79 days) and in group II for 19 days (4-31 days). The mortality rate was 10% in this series. CONCLUSION: Our data provide further evidence that early stabilization of spinal injuries is safe in severely injured patients, does not impair perioperative lung function, and results in a reduced overall ICU and hospital stay. Further prospective randomized investigations are warranted to prove these results.


Asunto(s)
Fijación Interna de Fracturas , Traumatismo Múltiple/cirugía , Insuficiencia Respiratoria/etiología , Fracturas de la Columna Vertebral/cirugía , Vértebras Torácicas/lesiones , Adolescente , Adulto , Anciano , Tornillos Óseos , Contusiones/complicaciones , Contusiones/mortalidad , Femenino , Humanos , Puntaje de Gravedad del Traumatismo , Tiempo de Internación , Vértebras Lumbares/lesiones , Vértebras Lumbares/cirugía , Lesión Pulmonar , Masculino , Persona de Mediana Edad , Traumatismo Múltiple/complicaciones , Traumatismo Múltiple/mortalidad , Insuficiencia Respiratoria/mortalidad , Estudios Retrospectivos , Fracturas de la Columna Vertebral/complicaciones , Fracturas de la Columna Vertebral/mortalidad , Análisis de Supervivencia , Vértebras Torácicas/cirugía , Factores de Tiempo
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