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1.
FEMS Microbiol Ecol ; 97(12)2021 12 17.
Artículo en Inglés | MEDLINE | ID: mdl-34792119

RESUMEN

A European transect was established, ranging from Sweden to the Azores, to determine the relative influence of geographic factors and agricultural small-scale management on the grassland soil microbiome. Within each of five countries (factor 'Country'), which maximized a range of geographic factors, two differing growth condition regions (factor 'GCR') were selected: a favorable region with conditions allowing for high plant biomass production and a contrasting less favorable region with a markedly lower potential. Within each region, grasslands of contrasting management intensities (factor 'MI') were defined: intensive and extensive, from which soil samples were collected. Across the transect, 'MI' was a strong differentiator of fungal community structure, having a comparable effect to continental scale geographic factors ('Country'). 'MI' was also a highly significant driver of bacterial community structure, but 'Country' was clearly the stronger driver. For both, 'GCR' was the weakest driver. Also at the regional level, strong effects of MI occurred on various measures of the soil microbiome (i.e. OTU richness, management-associated indicator OTUs), though the effects were largely regional-specific. Our results illustrate the decisive influence of grassland MI on soil microbial community structure, over both regional and continental scales, and, thus, highlight the importance of preserving rare extensive grasslands.


Asunto(s)
Micobioma , Suelo , Pradera , Plantas , Microbiología del Suelo
2.
BMC Public Health ; 20(1): 1044, 2020 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-32611334

RESUMEN

BACKGROUND: Owing to communication challenges and a lack of knowledge about the health care system, refugees may be at risk of having limited health literacy, meaning that they will have problems in achieving, understanding, appraising and using health information or navigating in the health care system. The aim of this study was to explore experiences and needs concerning health related information for newly arrived refugees in Sweden. METHODS: A qualitative design with a focus group methodology was used. The qualitative content analysis was based on seven focus group discussions, including 28 Arabic and Somali speaking refugees. RESULTS: Four categories emerged. 'Concrete instructions and explanations' includes appreciation of knowledge about how to act when facing health problems. 'Contextual knowledge' comprises experienced needs of information about the health care system, about specific health risks and about rights in health issues. 'A variation of sources' describes suggestions as to where and how information should be given. 'Enabling communication' includes the wish for more awareness among professionals from a language and cultural point of view. CONCLUSION: Concrete instructions and explanations are experienced as valuable and applicable. Additional information about health issues and the health care system is needed. Information concerning health should be spread by a variety of sources. Health literate health organizations are needed to meet the health challenges of refugees, including professionals that emphasize health literacy.


Asunto(s)
Alfabetización en Salud/métodos , Alfabetización en Salud/estadística & datos numéricos , Evaluación de Necesidades/estadística & datos numéricos , Refugiados/estadística & datos numéricos , Adulto , Anciano , Comunicación , Femenino , Grupos Focales , Humanos , Lenguaje , Masculino , Persona de Mediana Edad , Somalia/etnología , Suecia , Adulto Joven
3.
NPJ Precis Oncol ; 2: 18, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30182064

RESUMEN

Development of antibody drugs against novel targets and pathways offers great opportunities to improve current cancer treatment. We here describe a phenotypic discovery platform enabling efficient identification of therapeutic antibody-target combinations. The platform utilizes primary patient cells throughout the discovery process and includes methods for differential phage display cell panning, high-throughput cell-based specificity screening, phenotypic in vitro screening, target deconvolution, and confirmatory in vivo screening. In this study the platform was applied on cancer cells from patients with Chronic Lymphocytic Leukemia resulting in discovery of antibodies with improved cytotoxicity in vitro compared to the standard of care, the CD20-specific monoclonal antibody rituximab. Isolated antibodies were found to target six different receptors on Chronic Lymphocytic Leukemia cells; CD21, CD23, CD32, CD72, CD200, and HLA-DR of which CD32, CD200, and HLA-DR appeared as the most potent targets for antibody-based cytotoxicity treatment. Enhanced antibody efficacy was confirmed in vivo using a patient-derived xenograft model.

4.
Scand J Occup Ther ; 23(5): 383-90, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26757859

RESUMEN

BACKGROUND: Persons with chronic pain report a range of occupational problems. The specific health needs of immigrants are judged to be poorly understood, and health systems are not prepared to respond adequately. Being an immigrant is regarded as a risk factor for the progression of chronic widespread pain into a state of disability. OBJECTIVES: To explore occupational life trajectories among immigrant women with chronic pain. MATERIAL AND METHODS: A qualitative content analysis was used to capture the latent meaning of experiences in individual interviews of eight women with immigrant background and chronic pain. RESULTS: An overarching theme, 'making the best of a conditional situation', representing the women's occupational life trajectories, covers the content of two categories: 'being controlled', including affected self-perception, social relations, and future prospects, and 'trying to deal with challenges', comprising a focus on resources, having trust in one's own judgements and getting help from others. CONCLUSION AND SIGNIFICANCE: The experiences demonstrate an occupational life controlled by internal and external factors and may be understood as a disrupted occupational life trajectory. This knowledge may be helpful to occupational therapists supporting immigrant women's attempts to regain a structured life despite the constant presence of pain.


Asunto(s)
Dolor Crónico/psicología , Emigración e Inmigración , Dolor Musculoesquelético/psicología , Actividades Cotidianas , Adulto , Anciano , Dolor Crónico/rehabilitación , Empleo , Femenino , Humanos , Control Interno-Externo , Relaciones Interpersonales , Entrevistas como Asunto , Persona de Mediana Edad , Dolor Musculoesquelético/rehabilitación , Investigación Cualitativa , Autoimagen , Normas Sociales , Participación Social , Suecia
5.
Cont Lens Anterior Eye ; 34(1): 12-6; quiz 50-1, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-20926333

RESUMEN

INTRODUCTION: The aim of the present study was to evaluate changes in spherical aberration and their effect on visual quality (visual acuity and contrast sensitivity) in both distance and near with different non-custom-made contact lenses. METHODS: A wavefront analyser was used to measure the aberrations in each subject's eyes uncorrected and with the contact lenses: a standard lens and two aspherical contact lenses. High-contrast visual acuity at distance was measured with Test-Chart 2000 (100% contrast) and at near with Sloan ETDRS Near Point chart (100% contrast). Low-contrast visual acuity at distance was measured with Test-Chart 2000 (10% contrast) and contrast measurements at near with Mars letter contrast sensitivity chart. RESULTS: Mean spherical aberration was positive for all pupil sizes in the uncorrected eye, residual spherical aberration was close to zero with the standard lens for all pupil sizes, whereas the two aspheric contact lenses over-corrected spherical aberration. The changes in aberration were statistically significant (p < 0.05) with all lenses. No significant difference could be detected between trial frame correction, spherical and aspherical soft contact lens designs with respect to visual quality. This was the case for both distance and near. CONCLUSION: The results are in line with previous studies and indicate that non-custom-made spherical aberration control contact lenses have little effect on visual quality as defined in this study.


Asunto(s)
Lentes de Contacto , Errores de Refracción/diagnóstico , Errores de Refracción/rehabilitación , Adolescente , Adulto , Equipos Desechables , Análisis de Falla de Equipo , Femenino , Humanos , Masculino , Diseño de Prótesis , Resultado del Tratamiento , Agudeza Visual , Adulto Joven
6.
Waste Manag ; 30(2): 236-45, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19796929

RESUMEN

A pilot plant was set up to treat leachate from an industrial landfill containing shredder residues of end-of-life vehicles and white goods. The treatment plant consisted of aeration and sedimentation steps for pre-treatment, and a filter. The plant was designed to simultaneously remove various types of pollutants. The efficiencies of pre-treatment and of the main treatment step were investigated over a period of 3 years at the landfill site. By continuous aeration of the leachate the concentrations of Fe and Mn were reduced by 55% and 49%, respectively. By prolonged sedimentation suspended solid content was noticeably reduced (72%). In the filter, consisting of a mixture of peat and carbon-containing ash as a treatment medium, very high reduction of polar organic compounds, e.g. phenol (74%), o-and p-cresol (91%), and 2,4-dimethylphenol (73%), high average reduction of metals, e.g. Pb (78%), Fe (74%), Cu (73%), Mn (56%), Sn (55%), and Zn (47%), and good average reduction of DOC (26%), Tot-N (23%) and NH4-N (46%) were achieved. Sixty non-polar compounds in the leachate, identified by GC-MS screening, occurred at trace level. Most of them were considerably reduced in the filter.


Asunto(s)
Filtración/instrumentación , Residuos Industriales/análisis , Purificación del Agua/métodos , Carbono/análisis , Concentración de Iones de Hidrógeno , Metales/análisis , Compuestos de Nitrógeno/análisis , Compuestos Orgánicos/análisis , Oxígeno/análisis , Material Particulado/análisis , Fenoles/análisis , Proyectos Piloto , Agua/análisis , Agua/normas
7.
Scand J Occup Ther ; 14(4): 230-9, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17852961

RESUMEN

The heterogeneity of diagnoses included in the concept of chronic pain, as well as differences in adaptation to the situation involving chronic illness, imply the need for a variety of rehabilitation forms. Despite evidence concerning the success of multidisciplinary behaviour-orientated rehabilitation programmes, not all participants experience the expected change. The aim of the present study was to develop and test the face validity and the stability over time of a Swedish self-administered questionnaire: the Conceptions of Pain and Rehabilitation Questionnaire (CPRQ) for persons with chronic pain. The questionnaire is to be used as a guiding tool in planning for rehabilitation. Its purpose is to distinguish between individuals with expectations of and motivation for active rehabilitation and those with expectations of more supportive forms of therapy. The face validity was mainly obtained by target-group discussions including persons with chronic pain and rehabilitation staff with experience in the rehabilitation of persons with chronic pain. The test-retest stability analysis was performed using a model for identifying occasional and systematic disagreement. The questionnaire in its final form showed face validity and reliability in terms of stability over time. Further steps in the development process will include laying down the guiding principles for the questionnaire, based on new focus-group discussions, and completing work on the manual by including information about the origin of the questionnaire and instructions for its administration. Thereafter, the next step in the development process will be a test of responsiveness, i.e. to examine the degree to which the questionnaire really serves its purpose.


Asunto(s)
Terapia Ocupacional , Dimensión del Dolor , Dolor/psicología , Dolor/rehabilitación , Encuestas y Cuestionarios , Adulto , Anciano , Enfermedad Crónica , Femenino , Humanos , Masculino , Persona de Mediana Edad , Curva ROC , Reproducibilidad de los Resultados , Suecia
8.
Environ Monit Assess ; 102(1-3): 309-21, 2005 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15869192

RESUMEN

Artemia salina has, for the first time, been used as test organism for acute toxicity of leachate water from three landfills (the municipal landfills at Kristianstad, Sweden and Siauliai, Lithuania, and an industrial landfill at Stena fragmenting AB, Halmstad, as well as for leachate from Kristianstad treated in different ways in a pilot plan). Artemia can tolerate the high concentrations of chloride ions found in such waters. Large differences in toxicities were found, the leachate from Siauliai being the most toxic one. To increase the selectivity in the measurements, a fractionation was done by using ion exchange to separate ammonium/ammonia and metal ions from the leachate, and activated carbon adsorbents for organic pollutants. The influence of some metals and phenol compounds on the toxicity was investigated separately. It was found that most of the toxicity emanated from the ammonium/ammonia components in the leachate. However, there was also a significant contribution n from organic pollutants, other than phenol compounds, since separate experiments had in this latter case indicated negligible impact. The concentrations of metals were at a level, shown by separate experiments, where only small contribution to the toxicity could be expected.


Asunto(s)
Artemia/efectos de los fármacos , Eliminación de Residuos , Pruebas de Toxicidad Aguda , Movimientos del Agua , Contaminantes Químicos del Agua/toxicidad , Amoníaco/análisis , Amoníaco/toxicidad , Animales , Artemia/fisiología , Cobre/análisis , Cobre/toxicidad , Larva/efectos de los fármacos , Larva/fisiología , Plomo/análisis , Plomo/toxicidad , Movimiento/efectos de los fármacos , Fenoles/análisis , Fenoles/toxicidad , Compuestos de Amonio Cuaternario/análisis , Compuestos de Amonio Cuaternario/toxicidad , Contaminantes Químicos del Agua/análisis , Zinc/análisis , Zinc/toxicidad
9.
Ann Occup Hyg ; 48(4): 327-38, 2004 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15191942

RESUMEN

Exposure to organic dust originating from biofuels can cause adverse health effects. In the present study we have assessed the dustiness in terms of microbial components and particles of various biofuels by using a rotating drum as a dust generator. Microbial components from straw, wood chips, wood pellets and wood briquettes were quantified by several methods. Excellent correlations (r >/= 0.85, P < 0.0001) were found: between lipopolysaccharide (LPS) (as determined by 3-hydroxy fatty acid analysis) and endotoxin (as determined by a Limulus test), cultivable bacteria, total number of bacteria and muramic acid; between endotoxin and cultivable bacteria, total number of bacteria and muramic acid; between total number of bacteria and muramic acid; between cultivable fungi and total number of fungi. Straw was dustier than the other biofuels in terms of actinomycetes, bacteria, muramic acid, endotoxin, LPS, particle mass and number of particles. One of the wood chips studied and the straws had comparatively high dustiness in terms of fungi, while both wood pellets and wood briquettes had comparatively low dustiness in terms of all microbial components. An initially high particle generation rate of straw and wood chips decreased over time whereas the particle generation rate of wood briquettes and wood pellets increased during a 5 min rotation period. Particles of non-microbial origin may be the determining factor for the health risk in handling briquettes and pellets. Straw dust contained significantly more microorganisms per particle than did wood chip dust, probably because bacteria were most abundant in straw dust. The concentrations of endotoxin and fungi were high in wood and straw dust; dust from one of the straws contained 3610 EU/mg and dust from one of the chips contained 7.3 x 10(6) fungal spores/mg. An exposure to 3 mg of straw or wood chips dust/m(3) (the Swedish and Danish OEL of unspecific inhalable dust) could cause exposures to endotoxin and fungi higher than levels were health symptoms are seen to develop. The very different levels of dustiness in terms of particles and microbial components of different biofuels shows that dustiness is an important health-relevant factor to consider when choosing among biofuels and when designing worksites for handling of biofuels.


Asunto(s)
Microbiología del Aire , Contaminantes Ocupacionales del Aire/análisis , Polvo/análisis , Contaminación del Aire Interior , Animales , Bacterias/aislamiento & purificación , Recuento de Colonia Microbiana , Endotoxinas/análisis , Hongos/aislamiento & purificación , Humanos , Exposición por Inhalación/análisis , Prueba de Limulus/métodos , Lipopolisacáridos/análisis , Ácidos Murámicos/análisis , Exposición Profesional/análisis , Picea , Triticum , Madera
10.
Phys Rev Lett ; 91(16): 161802, 2003 Oct 17.
Artículo en Inglés | MEDLINE | ID: mdl-14611391

RESUMEN

High statistics calorimetric measurements of the beta spectrum of 187Re are being performed with arrays of silver perrhenate crystals operated at low temperature. After a substantial modification of the experimental setup, a new measurement with ten silver perrhenate microbolometers has been running since July 2002. The crystals have masses around 300 microg and their average FWHM energy resolution is of 28.3 eV at the beta end point. The Kurie plot collected during 4485 h x mg effective running time has an end-point energy of 2466.1+/-0.8(stat)+/-1.5(syst) eV, while the half lifetime of the decay is found to be 43.2+/-0.2(stat)+/-0.1(syst) Gy. These values are the most precise obtained so far for 187Re. The best fit value for m(2)(nu(e)) is 147+/-237(stat)+/-90(syst) eV(2), which corresponds to an upper limit for the electron antineutrino mass m(nu(e))< or =21.7 eV at 90% C.L.

11.
Anal Biochem ; 296(2): 188-96, 2001 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-11554714

RESUMEN

The development of commercial biosensors based on surface plasmon resonance has made possible careful characterization of biomolecular interactions. Here, a set of destabilized human carbonic anhydrase II (HCA II) mutants was investigated with respect to their interaction kinetics with two different immobilized benzenesulfonamide inhibitors. Point mutations were located distantly from the active site, and the destabilization energies were up to 23 kJ/mol. The dissociation rate of wild-type HCA II, as determined from the binding to the inhibitor with higher affinity, was 0.019 s(-1). For the mutants, dissociation rates were faster (0.022-0.025 s(-1)), and a correlation between faster dissociation and a high degree of destabilization was observed. We interpreted these results in terms of increased dynamics of the tertiary structures of the mutants. This interpretation was supported by entropy determinations, showing that the entropy of the native structure significantly increased upon destabilization of the protein molecule. Our findings demonstrate the applicability of modern biosensor technology in the study of subtle details in molecular interaction mechanisms, such as the long-range effect of point mutations on interaction kinetics.


Asunto(s)
Técnicas Biosensibles/métodos , Anhidrasa Carbónica II/análisis , Resonancia por Plasmón de Superficie/métodos , Anhidrasa Carbónica II/genética , Humanos , Cinética , Modelos Moleculares , Mutación , Sulfonamidas/química , Bencenosulfonamidas
12.
Int J Prosthodont ; 14(4): 303-9, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11508083

RESUMEN

PURPOSE: The purpose of this report is to describe a new technique to fabricate and deliver an implant-supported fixed prosthesis to the patient on the day of surgery, and to propose a protocol for the prosthodontic and dental laboratory procedures. MATERIALS AND METHODS: The development of the Brånemark Novum prosthodontic protocol is reviewed, and clinical and dental laboratory assessments and methods are described. RESULTS: The total treatment time to fabricate a permanent implant-supported fixed prosthesis in the mandible can be reduced to 1 day with the Brånemark Novum technique. The new method includes a precise surgical technique using drilling templates for predetermined implant positions, a rigid splinting of the implants immediately after placement, the use of a prefabricated titanium framework, and elimination of implant impression procedures. CONCLUSION: With the technique described in this report, it is possible to provide patients with a permanent implant-supported fixed prosthesis in the mandible on the day of implant surgery. Patient benefits are obvious, with drastically reduced total treatment time, lower cost, and fewer clinical visits.


Asunto(s)
Implantación Dental Endoósea/métodos , Diseño de Prótesis Dental/métodos , Prótesis Dental de Soporte Implantado , Dentadura Completa Inmediata , Arcada Edéntula/rehabilitación , Implantación Dental Endoósea/instrumentación , Implantes Dentales , Diseño de Prótesis Dental/economía , Retención de Prótesis Dentales/instrumentación , Dentadura Completa Inferior , Episodio de Atención , Humanos , Mandíbula/cirugía , Férulas (Fijadores) , Factores de Tiempo
13.
Lancet ; 358(9281): 534-8, 2001 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-11520523

RESUMEN

BACKGROUND: Previous studies indicate that analysis of the ST waveform of the fetal electrocardiogram provides information on the fetal response to hypoxia. We did a multicentre randomised controlled trial to test the hypothesis that intrapartum monitoring with cardiotocography combined with automatic ST-waveform analysis results in an improved perinatal outcome compared with cardiotocography alone. METHODS: At three Swedish labour wards, 4966 women with term fetuses in the cephalic presentation entered the trial during labour after a clinical decision had been made to apply a fetal scalp electrode for internal cardiotocography. They were randomly assigned monitoring with cardiotocography plus ST analysis (CTG+ST group) or cardiotocography only (CTG group). The main outcome measure was rate of umbilical-artery metabolic acidosis (pH <7.05 and base deficit >12 mmol/L). Secondary outcomes included operative delivery for fetal distress. Results were first analysed according to intention to treat, and secondly after exclusion of cases with severe malformations or with inadequate monitoring. FINDINGS: The CTG+ST group showed significantly lower rates of umbilical-artery metabolic acidosis than the cardiotocography group (15 of 2159 [0.7%] vs 31 of 2079 [2%], relative risk 0.47 [95% CI 0.25-0.86], p=0.02) and of operative delivery for fetal distress (193 of 2519 [8%] vs 227 of 2447 [9%], 0.83 [0.69-0.99], p=0.047) when all cases were included according to intention to treat. The differences were more pronounced after exclusion of 291 in the CTG+ST group and 283 in the CTG group with malformations or inadequate recording. INTERPRETATION: Intrapartum monitoring with cardiotocography combined with automatic ST-waveform analysis increases the ability of obstetricians to identify fetal hypoxia and to intervene more appropriately, resulting in an improved perinatal outcome.


Asunto(s)
Acidosis/diagnóstico , Cardiotocografía , Electrocardiografía , Monitoreo Fetal/métodos , Hipoxia Encefálica/diagnóstico , Cesárea/estadística & datos numéricos , Distribución de Chi-Cuadrado , Parto Obstétrico/estadística & datos numéricos , Femenino , Sangre Fetal , Sufrimiento Fetal/diagnóstico , Frecuencia Cardíaca Fetal , Humanos , Concentración de Iones de Hidrógeno , Hipoxia Encefálica/prevención & control , Embarazo , Resultado del Embarazo , Factores de Riesgo , Suecia , Arterias Umbilicales
14.
Biophys J ; 80(6): 2886-97, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11371461

RESUMEN

Four doubly spin-labeled variants of human carbonic anhydrase II and corresponding singly labeled variants were prepared by site-directed spin labeling. The distances between the spin labels were obtained from continuous-wave electron paramagnetic resonance spectra by analysis of the relative intensity of the half-field transition, Fourier deconvolution of line-shape broadening, and computer simulation of line-shape changes. Distances also were determined by four-pulse double electron-electron resonance. For each variant, at least two methods were applicable and reasonable agreement between methods was obtained. Distances ranged from 7 to 24 A. The doubly spin-labeled samples contained some singly labeled protein due to incomplete labeling. The sensitivity of each of the distance determination methods to the non-interacting component was compared.


Asunto(s)
Anhidrasas Carbónicas/química , Espectroscopía de Resonancia por Spin del Electrón/métodos , Marcadores de Spin , Anhidrasas Carbónicas/genética , Anhidrasas Carbónicas/aislamiento & purificación , Humanos , Modelos Moleculares , Mutagénesis Sitio-Dirigida , Conformación Proteica
15.
Biophys J ; 80(6): 2867-85, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11371460

RESUMEN

Two different spin labels, N-(1-oxyl-2,2,5,5-tetramethyl-3-pyrrolidinyl)iodoacetamide (IPSL) and (1-oxyl-2,2,5,5-tetramethylpyrroline-3-methyl) methanethiosulfonate (MTSSL), and two different fluorescent labels 5-((((2-iodoacetyl)amino)-ethyl)amino)naphtalene-1-sulfonic acid (IAEDANS) and 6-bromoacetyl-2-dimetylaminonaphtalene (BADAN), were attached to the introduced C79 in human carbonic anhydrase (HCA II) to probe local structural changes upon unfolding and aggregation. HCA II unfolds in a multi-step manner with an intermediate state populated between the native and unfolded states. The spin label IPSL and the fluorescent label IAEDANS reported on a substantial change in mobility and polarity at both unfolding transitions at a distance of 7.4-11.2 A from the backbone of position 79. The shorter and less flexible labels BADAN and MTSSL revealed less pronounced spectroscopic changes in the native-to-intermediate transition, 6.6-9.0 A from the backbone. At intermediate guanidine (Gu)-HCl concentrations the occurrence of soluble but irreversibly aggregated oligomeric protein was identified from refolding experiments. At approximately 1 M Gu-HCl the aggregation was found to be essentially complete. The size and structure of the aggregates could be varied by changing the protein concentration. EPR measurements and line-shape simulations together with fluorescence lifetime and anisotropy measurements provided a picture of the self-assembled protein as a disordered protein structure with a representation of both compact as well as dynamic and polar environments at the site of the molecular labels. This suggests that a partially folded intermediate of HCA II self-assembles by both local unfolding and intermolecular docking of the intermediates vicinal to position 79. The aggregates were determined to be 40-90 A in diameter depending on the experimental conditions and spectroscopic technique used.


Asunto(s)
Anhidrasas Carbónicas/química , Anhidrasas Carbónicas/metabolismo , Colorantes Fluorescentes/metabolismo , Sondas Moleculares/metabolismo , Pliegue de Proteína , Marcadores de Spin , Sustitución de Aminoácidos/genética , Anhidrasas Carbónicas/genética , Dicroismo Circular , Simulación por Computador , Cisteína/genética , Cisteína/metabolismo , Difusión , Espectroscopía de Resonancia por Spin del Electrón , Estabilidad de Enzimas , Polarización de Fluorescencia , Humanos , Modelos Moleculares , Conformación Proteica , Desnaturalización Proteica , Renaturación de Proteína , Rotación , Electricidad Estática , Relación Estructura-Actividad
16.
Biophys Chem ; 94(3): 245-56, 2001 Dec 25.
Artículo en Inglés | MEDLINE | ID: mdl-11804734

RESUMEN

Phase memory relaxation times (T(M) or T(2)) of spin labels in human carbonic anhydrase II (HCA II) are reported. Spin labels (N-(1-oxyl-2,2,5,5-tetramethyl-3-pyrrolidinyl)iodoacetamide, IPSL) were introduced at cysteines, by site-directed mutagenesis at seven different positions in the protein. By two pulse electron paramagnetic resonance (EPR), electron spin echo decays at 45 K are measured and fitted by stretched exponentials, resulting in relaxation parameters T(M) and x. T(M) values of seven positions are between 1.6 micros for the most buried residue (L79C) and 4.7 micros for a residue at the protein surface (W245C). In deuteriated buffer, longer T(M) are found for all but the most buried residues (L79C and W97C), and electron spin echo envelop modulation (ESEEM) of deuterium nuclei is observed. Different deuterium ESEEM patterns for W95C and W16C (surface residue) indicate differences in the local water concentration, or accessibility, of the spin label by deuterium. We propose T(M) as a parameter to determine the spin label location in proteins. Furthermore, these systems are interesting for studying the pertaining relaxation mechanism.


Asunto(s)
Anhidrasa Carbónica II/química , Marcadores de Spin , Anhidrasa Carbónica II/genética , Espectroscopía de Resonancia por Spin del Electrón/métodos , Transferencia de Energía , Semivida , Humanos , Mutagénesis Sitio-Dirigida
17.
BJOG ; 107(10): 1248-51, 2000 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11028576

RESUMEN

OBJECTIVE: To investigate whether, during injections of sterile water, there is any difference in perceived pain between intracutaneous and subcutaneous injections. DESIGN: Blind controlled trial with cross-over design. SETTING: Göteborg and Skövde, Sweden. PARTICIPANTS: One hundred healthy female volunteers. METHODS: The women were randomised into two groups and subjected to two trials, within one week of each other. During the first trial one group (n = 50) received the intracutaneous injection first, followed by the subcutaneous injection. The second group (n = 50) was given the subcutaneous injection first, followed by intracutaneous injection. In both groups all the injections were given in reverse order during the second trial. MAIN OUTCOME MEASURES: Experienced pain during the administration of sterile water injections, measured by visual analogue scale. RESULTS: The analysis showed intracutaneous injections to be significantly more painful than subcutaneous injections, even after adjusting for injection day and for left/right site of injection (mean 60.8 vs 41.3, P < 0.001). CONCLUSIONS: The findings suggest that the less painful subcutaneous injection technique should be used.


Asunto(s)
Analgesia Obstétrica/métodos , Trabajo de Parto , Dolor/prevención & control , Agua/administración & dosificación , Adolescente , Adulto , Analgesia Epidural/métodos , Estudios Cruzados , Método Doble Ciego , Femenino , Humanos , Inyecciones Intradérmicas/efectos adversos , Inyecciones Subcutáneas/efectos adversos , Dolor de la Región Lumbar/prevención & control , Persona de Mediana Edad , Dolor/etiología , Dimensión del Dolor , Embarazo
18.
Life Sci ; 66(11): 1003-10, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-10724447

RESUMEN

Pigment aggregation in melanophores of Labrus ossifagus is controlled by an alpha2-adrenoceptor and is somehow modulated by melatonin. The signal transduction mechanisms seem to involve both an attenuation of cAMP and an increase in intracellular Ca2+, inhibiting protein kinase A or activating a phosphatase, respectively. These effects result in dephosphorylation, which in turn induces aggregation. Various alpha2-adrenoceptor agonists attenuate cAMP levels or increase the concentration of intracellular Ca2+. Noradrenaline, for example, lowers cAMP but does not affect the calcium signal whereas B-HT 920, an alpha2-adrenoceptor specific agonist, does not induce a cAMP decrease but does appear to induce an increase in intracellular Ca2+. This later inference is drawn from experiments with BAPTA/AM, an intracellular calcium chelator, which counteracts the aggregation induced by B-HT 920. Interestingly, the very potent alpha2-adrenoceptor agonist medetomidine apparently activates both signal transduction pathways, which could explain its high efficacy in producing aggregation. Melatonin itself does not cause pigment aggregation, but it potentiates noradrenaline-induced aggregation. It has been suggested that melatonin receptors and alpha2-adrenoceptors follow the same signal transduction pathway, i.e. an attenuation of cAMP. In our experiments, melatonin did not reduce cAMP levels; instead it appears to increase Ca2+ concentration, since melatonin-potentiated aggregation was inhibited by BAPTA/AM. Thus, aggregation amplified by melatonin is probably not mediated by a further decrease in cAMP, but by the same signal transduction mechanism as B-HT 920, i.e. an increase in Ca2+. This further strengthens the suggestion that melatonin and B-HT 920 bind to the same site, but it is unclear if that particular site is on the melatonin receptor or the alpha2-adrenoceptor.


Asunto(s)
Aves/fisiología , Calcio/fisiología , Melanóforos/fisiología , Melatonina/fisiología , Sistemas de Mensajero Secundario , Animales , Azepinas/farmacología , AMP Cíclico/fisiología , Medetomidina/farmacología , Melanóforos/efectos de los fármacos , Melatonina/farmacología , Norepinefrina/farmacología , Norepinefrina/fisiología , Transducción de Señal , Yohimbina/farmacología
19.
J Biol Chem ; 274(46): 32897-903, 1999 Nov 12.
Artículo en Inglés | MEDLINE | ID: mdl-10551854

RESUMEN

Protein aggregation plays an important role in biotechnology and also causes numerous diseases. Human carbonic anhydrase II is a suitable model protein for studying the mechanism of aggregation. We found that a molten globule state of the enzyme formed aggregates. The intermolecular interactions involved in aggregate formation were localized in a direct way by measuring excimer formation between each of 20 site-specific pyrene-labeled cysteine mutants. The contact area of the aggregated protein was very specific, and all sites included in the intermolecular interactions were located in the large beta-sheet of the protein, within a limited region between the central beta-strands 4 and 7. This substructure is very hydrophobic, which underlines the importance of hydrophobic interactions between specific beta-sheet containing regions in aggregate formation.


Asunto(s)
Anhidrasas Carbónicas/química , Conformación Proteica , Anhidrasas Carbónicas/genética , Chaperonina 60/metabolismo , Cisteína/genética , Colorantes Fluorescentes , Humanos , Maleimidas/química , Modelos Moleculares , Mutación , Desnaturalización Proteica , Pliegue de Proteína , Estructura Secundaria de Proteína , Espectrometría de Fluorescencia , Triptófano/química
20.
Neurosci Lett ; 275(2): 113-6, 1999 Nov 12.
Artículo en Inglés | MEDLINE | ID: mdl-10568512

RESUMEN

The present study examines noradrenaline (NA) effects on melanophore pigment aggregation in normal, denervated and reinnervated teleost skin in vitro. Many axons were present in the melanophore-containing layer of normal skin. One week after a nerve crush lesion the skin was devoid of axons. By 1 month the skin was partly reinnervated. One day after nerve crush NA-sensitivity was markedly increased compared to controls. Sensitivity then approached normality but it remained elevated for at least one month. We conclude that melanophore supersensitivity develops very rapidly upon denervation and then gradually fades away during reinnervation.


Asunto(s)
Melanóforos/fisiología , Norepinefrina/farmacología , Percas , Pigmentación de la Piel/efectos de los fármacos , Piel/inervación , Animales , Desnervación
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