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We report direction detection constraints on the presence of hidden photon dark matter with masses between 20-30 µeV c^{-2}, using a cryogenic emitter-receiver-amplifier spectroscopy setup designed as the first iteration of QUALIPHIDE (quantum limited photons in the dark experiment). A metallic dish sources conversion photons, from hidden photon kinetic mixing, onto a horn antenna which is coupled to a C band kinetic inductance traveling wave parametric amplifier, providing for near quantum-limited noise performance. We demonstrate a first probing of the kinetic mixing parameter χ to the 10^{-12} level for the majority of hidden photon masses in this region. These results not only represent stringent constraints on new dark matter parameter space, but are also the first demonstrated use of wideband quantum-limited amplification for astroparticle applications.
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Fotones , CinéticaRESUMEN
BACKGROUND: Tooth decay (caries) is a significant health burden in young children. There is strong evidence for the benefits of establishing appropriate home-based oral health behaviours in early childhood. Dental teams are well placed to provide this information and there is clear advice on what oral health information should be given to parents. However, research has shown that there is limited guidance, training and resources on how dental teams should deliver this advice. "Strong Teeth" is a complex oral health intervention, using evidence-based resources and training underpinned by behaviour change psychology, to support behaviour change conversations in dental practice. This early phase evaluation aims to assess the feasibility of this intervention, prior to a full-scale trial. METHODS: The study recruited 15 parents of children aged 0-2-years-old and 21 parents of children aged 3-5 years old, from five NHS dental practices across West Yorkshire. Participant demographics, self-reported brushing behaviours, dietary habits, a dental examination and three objective measures of toothbrushing were collected in a home-setting at baseline, then at 2-weeks and 2-months post-intervention. Recruitment, retention and intervention delivery were analysed as key process outcomes. Brushing habits were compared to national toothbrushing guidelines - the Delivering Better Oral Health toolkit (Public Health England). RESULTS: Strong Teeth was feasible to deliver in a General Dental Practice setting in 94% of cases. Feasibility of recruitment (37%) exceeded progression criterion, however retention of participants (75%) was below the progression criterion for the 0-2 age group. More than half of children recruited aged 3-5-years had caries experience (52%). Total compliance to toothbrushing guidance at baseline was low (28%) and increased after the intervention (52%), an improvement that was statistically significant. Dietary habits remained largely unchanged. Plaque scores significantly decreased in the 3-5-year-olds and toothbrushing duration increased in all age groups. CONCLUSION: "Strong Teeth" intervention delivery and data collection in the home setting was feasible. There was a positive indication of impact on reported toothbrushing behaviours. Some amendments to study design, particularly relating to the inclusion of the 0-2-year-old group, should be considered before progression to a full trial. Trial registration ISRCTN Register: ISRCTN10709150. Registered retrospectively 24/7/2019.
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Caries Dental , Salud Bucal , Niño , Preescolar , Caries Dental/prevención & control , Inglaterra , Estudios de Factibilidad , Humanos , Lactante , Recién Nacido , Padres , Estudios Retrospectivos , Cepillado DentalRESUMEN
INTRODUCTION: Dental treatment for children requires not only technical skills, but also the knowledge and confidence to provide behaviour management to support children of differing ages and stages of development. It is not surprising then that dental students find treating children especially stressful. Paediatric dentistry training is therefore a vital element of the undergraduate dental curriculum. MATERIALS AND METHODS: Eighty-six fourth-year undergraduate dental students received standard lectures and seminars about behaviour management techniques for children having local anaesthetic. The students were then randomly divided into groups using cluster randomisation. The intervention group received an intervention-based around video clips (VCs) demonstrating behaviour management techniques (BMTs) for children receiving local anaesthetic The intervention and control groups completed self-administered questionnaires to determine their level of confidence in managing local anaesthetic for children. RESULTS: There was a statistically significant difference in the level of confidence between the groups immediately after the teaching intervention (P=.003) and at 4 months (P=.001) in favour of the video group. DISCUSSION: Previous studies on the use of video as a teaching aid have reported favourable results in terms of both student attitudes and learning outcomes. The results from this study confirm the benefits of this style of teaching paediatric behaviour skills in the undergraduate dental curriculum, and the benefits were maintained at 4 months. CONCLUSION: This study has demonstrated that VCs as an additional teaching aid are an effective method in improving students' confidence for BMTs when delivering local anaesthetic.
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Anestesia Dental , Anestesia Local , Recursos Audiovisuales , Competencia Clínica , Educación en Odontología/métodos , Odontología Pediátrica/educación , Grabación en Video , Niño , HumanosRESUMEN
Both maternal 25-hydroxyvitamin D (25(OH)D) concentrations during pregnancy and placental amino acid transporter gene expression have been associated with development of the offspring in terms of body composition and bone structure. Several amino acid transporter genes have vitamin D response elements in their promoters suggesting the possible linkage of these two mechanisms. We aimed to establish whether maternal 25(OH)D and vitamin D-binding protein (VDBP) levels relate to expression of placental amino acid transporters. RNA was extracted from 102 placental samples collected in the Southampton Women's Survey, and gene expression was analysed using quantitative real-time PCR. Gene expression data were normalised to the geometric mean of three housekeeping genes, and related to maternal factors and childhood body composition. Maternal serum 25(OH)D and VDBP levels were measured by radioimmunoassay. Maternal 25(OH)D and VDBP levels were positively associated with placental expression of specific genes involved in amino acid transport. Maternal 25(OH)D and VDBP concentrations were correlated with the expression of specific placental amino acid transporters, and thus may be involved in the regulation of amino acid transfer to the fetus. The positive correlation of VDBP levels and placental transporter expression suggests that delivery of vitamin D to the placenta may be important. This exploratory study identifies placental amino acid transporters which may be altered in response to modifiable maternal factors and provides a basis for further studies.
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Aminoácidos/metabolismo , Placenta/metabolismo , Proteína de Unión a Vitamina D/fisiología , Vitamina D/fisiología , Adulto , Sistemas de Transporte de Aminoácidos/genética , Transporte Biológico , Composición Corporal , Estudios de Cohortes , Femenino , Expresión Génica/fisiología , Edad Gestacional , Encuestas Epidemiológicas , Humanos , Recién Nacido , Masculino , Intercambio Materno-Fetal , Placenta/química , Embarazo , ARN Mensajero/análisis , Reino Unido , Vitamina D/análogos & derivados , Vitamina D/sangre , Proteína de Unión a Vitamina D/sangre , Salud de la Mujer , Adulto JovenRESUMEN
The term primary empty sella (PES) makes reference to the herniation of the subarachnoid space within the sella turcica in patients with no history of pituitary tumor, surgery or radiotherapy. To retrospectively assess clinical features, radiological findings and the biochemical endocrine function from the records of 175 patients with a diagnosis of PES. One hundred seventy-five patients (150 females) were studied. The mean age at diagnosis was 48.2 ± 14 year. Most diagnoses were made by magnetic resonance imaging (n = 172). In most patients, the pituitary function was assessed by basal pituitary hormones measurements. Pituitary scans were ordered for different reasons: headache (33.1 %), endocrine disorders (30.6 %), neurological symptoms (12.5 %), visual disturbances (8.75 %), abnormalities on sella turcica radiograph (8.75 %) and others (6.25 %). Multiple pregnancies were observed in 58.3 % of women; headaches, obesity, and hypertension were found in 59.4, 49.5, and 27.3 % of the studied population, respectively. Mild hyperprolactinemia (<50 ng/ml) was present in 11.6 % of women and 17.3 % of men. Twenty-eight percent of our patients had some degree of hypopituitarism. In the male population, hypopituitarism represented 64 % of cases, whereas it accounted for 22 % of all females. PES seems to be more commonly found in middle-aged women, with a history of multiple pregnancies. In most patients, PES was discovered as an incidental finding on imaging studies, while in almost a quarter of patients PES was found during the diagnostic evaluation of anterior pituitary deficiency, which was more common in men.
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Síndrome de Silla Turca Vacía/patología , Adulto , Síndrome de Silla Turca Vacía/diagnóstico por imagen , Femenino , Humanos , Hiperprolactinemia , Hipopituitarismo/diagnóstico por imagen , Hipopituitarismo/patología , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Radiografía , Estudios Retrospectivos , Silla Turca/diagnóstico por imagen , Silla Turca/patologíaRESUMEN
A whole-genome radiation hybrid (RH) panel was used to construct a high-resolution map of the rat genome based on microsatellite and gene markers. These include 3,019 new microsatellite markers described here for the first time and 1,714 microsatellite markers with known genetic locations, allowing comparison and integration of maps from different sources. A robust RH framework map containing 1,030 positions ordered with odds of at least 1,000:1 has been defined as a tool for mapping these markers, and for future RH mapping in the rat. More than 500 genes which have been mapped in mouse and/or human were localized with respect to the rat RH framework, allowing the construction of detailed rat-mouse and rat-human comparative maps and illustrating the power of the RH approach for comparative mapping.
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Marcadores Genéticos/genética , Genoma , Ratas/genética , Animales , Mapeo Cromosómico , Cromosomas/genética , Genes/genética , Humanos , Células Híbridas , Ratones , Datos de Secuencia MolecularRESUMEN
In this work we explored the selectivity of single nucleobases towards adsorption on chiral single-wall carbon nanotubes (SWCNTs) by density functional theory calculations. Specifically, the adsorption of molecular models of guanine (G), adenine (A), thymine (T), and cytosine (C), as well as of AT and GC Watson-Crick (WC) base pairs on chiral SWCNT C(6, 5), C(9, 1) and C(8, 3) model structures, was analyzed in detail. The importance of correcting the exchange-correlation functional for London dispersion was clearly demonstrated, yet limitations in modeling such interactions by considering the SWCNT as a molecular model may mask subtle effects in a molecular-macroscopic material system. The trend in the calculated adsorption energies of the nucleobases on same diameter C(6, 5) and C(9, 1) SWCNT surfaces, i.e., G > A > T > C, was consistent with related computations and experimental work on graphitic surfaces, however contradicting experimental data on the adsorption of single-strand short homo-oligonucleotides on SWCNTs that demonstrated a trend of G > C > A > T (Albertorio et al 2009 Nanotechnology 20 395101). A possible role of electrostatic interactions in this case was partially captured by applying the effective fragment potential method, emphasizing that the interplay of the various contributions in modeling nonbonded interactions is complicated by theoretical limitations. Finally, because the calculated adsorption energies for Watson-Crick base pairs have shown little effect upon adsorption of the base pair farther from the surface, the results on SWCNT sorting by salmon genomic DNA could be indicative of partial unfolding of the double helix upon adsorption on the SWCNT surface.
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Modelos Químicos , Modelos Moleculares , Nanotubos de Carbono/química , Nanotubos de Carbono/ultraestructura , Ácidos Nucleicos/química , Ácidos Nucleicos/ultraestructura , Adsorción , Sitios de Unión , Simulación por Computador , Sustancias Macromoleculares/química , Conformación Molecular , Tamaño de la Partícula , Propiedades de SuperficieRESUMEN
The aim of designing and fabricating the surgical templates was to assist the surgical component of premolar transplantation, by establishing and replicating the root dimensions of the donor premolar tooth. The correct template could be used to assess the socket preparation (width and depth) prior to placement of the transplant in the recipient site, obviating the need to repeatedly try the donor tooth for fit at the recipient site, thereby minimising trauma to the periodontal ligament of the donor tooth. Seventy-five mandibular premolars and 50 maxillary second premolars were selected with varying stages of root development. All teeth had been extracted for orthodontic reasons. The root was measured for its length (maxL) and maximum (maxW) and minimum width (minW) with digital callipers from standardised reference points. These measurements were then used in the design of premolar transplant templates. The mean measurements for second maxillary premolars were maxL 14.6 mm (± 1.7), maxW 8.3 mm (± 0.5) and minW 4.9 (± 0.3). The mean measurements for mandibular premolars were maxL 14.8 (± 1.6), maxW 7.4 (± 0.6) and minW 5.3 (± 0.5). From these measurements, a range of maxillary second premolar and mandibular premolar templates have been fabricated. These figures also inform the multidisciplinary planning process for the space requirements at the donor site prior to transplantation.
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Anatomía Transversal , Diente Premolar/trasplante , Modelos Anatómicos , Alveolo Dental/anatomía & histología , Adolescente , Diente Premolar/anatomía & histología , Precisión de la Medición Dimensional , Humanos , Planificación de Atención al Paciente , Estudios Prospectivos , Raíz del Diente/anatomía & histología , Trasplante AutólogoRESUMEN
Superconducting On-chip Fourier Transform Spectrometers (SOFTS) are broadband, ultra-compact and electronic interferometers. SOFTS will enable kilo-pixel spectro-imaging focal planes, enhancing sub-millimeter astrophysics and cosmology. Particular applications include cluster astrophysics, cosmic microwave background (CMB) science, and line intensity mapping. This article details the development, design and bench-marking of radio frequency (RF) on-chip architecture of SOFTS for Ka and W-bands.
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Fetal growth depends on placental transfer of amino acids from maternal to fetal blood. The mechanisms of net amino acid efflux across the basal membrane (BM) of the placental syncytiotrophoblast to the fetus, although vital for amino acid transport, are poorly understood. We examined the hypothesis that facilitated diffusion by the amino acid transporters TAT1, LAT3 and LAT4 plays an important role in this process, with possible effects on fetal growth. Amino acid transfer was measured in isolated perfused human placental cotyledons (n = 5 per experiment) using techniques which distinguish between different transport processes. Placental TAT1, LAT3 and LAT4 proteins were measured, and mRNA expression levels (measured using real-time quantitative-PCR) were related to fetal and neonatal anthropometry and dual-energy X-ray absorptiometry measurements of neonatal lean mass in 102 Southampton Women's Survey (SWS) infants. Under conditions preventing transport by amino acid exchangers, all amino acids appearing in the fetal circulation were substrates of TAT1, LAT3 or LAT4. Western blots demonstrated the presence of TAT1, LAT3 and LAT4 in placental BM preparations. Placental TAT1 and LAT3 mRNA expression were positively associated with measures of fetal growth in SWS infants (P < 0.05). We provide evidence that the efflux transporters TAT1, LAT3 and LAT4 are present in the human placental BM, and may play an important role in the net efflux of amino acids to the fetus. Unlike other transporters they can increase fetal amino acid concentrations. Consistent with a role in placental amino acid transfer capacity and fetal growth TAT1 and LAT3 mRNA expression showed positive associations with infant size at birth.
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Sistemas de Transporte de Aminoácidos/fisiología , Aminoácidos/metabolismo , Feto/metabolismo , Intercambio Materno-Fetal/fisiología , Placenta/metabolismo , Trofoblastos/metabolismo , Adulto , Sistemas de Transporte de Aminoácidos Básicos/fisiología , Sistemas de Transporte de Aminoácidos Neutros/fisiología , Recolección de Datos/métodos , Femenino , Feto/irrigación sanguínea , Humanos , Recién Nacido , Placenta/irrigación sanguínea , Embarazo , Adulto JovenRESUMEN
INTRODUCTION: Craniopharyngiomas are a big challenge in the neurosurgical field. Because these lesions involve important systems, surgeons must weigh the risks of aggressive resection against the long-term challenges of recurrence. We present the outcomes of our patients based on clinical results, degree of resection, recurrence and disease-free survival. MATERIALS AND METHODS: We reviewed medical records in all patients who had undergone surgical resection for craniopharyngioma at (Hospital Italiano de Buenos Aires) between 2007 and 2019. We considered ophthalmological examinations, imaging studies, endocrinological studies and surgical complications. Radical resections were planned in all of the patients. To help choose the correct surgical approach, craniopharyngiomas were classified based on tumor location. RESULTS: Thirty cases of craniopharyngioma were analysed. 12.5% were classified as intrasellar, 12.5% as prechiasmatic, 43.75% as retrochiasmatic, and 31.25% as intraventricular. Overall, 38 cases involved a transcranial surgery (15 orbitozygomatic approach; 19 pterional approach and 4 transcallosal approach), seven involved a transsphenoidal approach, two microscopic transnasal approach and one ventricular endoscopy for emptying the craniopharyngioma cyst. Gross-total resection was achieved in 43.7% and near-total resection (more than 90%) in 25%. The mean follow-up period after resection was 4.7 years. Tumor recurrence occurred in 48%, with an average of 42.7 disease-free months. CONCLUSION: Total tumor resection is the best treatment for craniopharyngioma. Due to its high morbidity and mortality, a multidisciplinary team is necessary for the management of these tumors.
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Craneofaringioma , Neoplasias Hipofisarias , Craneofaringioma/diagnóstico por imagen , Craneofaringioma/cirugía , Humanos , Recurrencia Local de Neoplasia/cirugía , Procedimientos Neuroquirúrgicos , Neoplasias Hipofisarias/diagnóstico por imagen , Neoplasias Hipofisarias/cirugía , Complicaciones Posoperatorias , Estudios Retrospectivos , Resultado del TratamientoRESUMEN
The development of aptamers on custom synthesized DNA microarrays, which has been demonstrated in recent publications, can facilitate detailed analyses of sequence and fitness relationships. Here we use the technique to observe the paths taken through sequence-fitness space by three different evolutionary regimes: asexual reproduction, recombination and model-based evolution. The different evolutionary runs are made on the same array chip in triplicate, each one starting from a small population initialized independently at random. When evolving to a common target protein, glucose-6-phosphate dehydrogenase (G6PD), these nine distinct evolutionary runs are observed to develop aptamers with high affinity and to converge on the same motif not present in any of the starting populations. Regime specific differences in the evolutions, such as speed of convergence, could also be observed.
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Aptámeros de Nucleótidos/química , Análisis de Secuencia por Matrices de Oligonucleótidos , Algoritmos , Aptámeros de Nucleótidos/genética , Simulación por Computador , Glucosafosfato Deshidrogenasa/química , Glucosafosfato Deshidrogenasa/metabolismo , Modelos GenéticosRESUMEN
The galaxy evolution probe (GEP) is a concept for a probe-class space observatory to study the physical processes related to star formation over cosmic time. To do so, the mid- and far-infrared (IR) spectra of galaxies must be studied. These mid- and far-IR observations require large multi-frequency arrays, sensitive detectors. Our goal is to develop low NEP aluminum kinetic inductance detectors (KIDs) for wavelengths of 10-400 µ m for the GEP and a pathfinder long-duration balloon (GEP-B) that will perform precursor GEP science. KIDs for the lower wavelength range (10-100 µ m ) have not been previously implemented. We present an absorber design for KIDs sensitive to wavelengths of 10 µ m shown to have around 75-80% absorption efficiency through ANSYS HFSS (high-frequency structure simulator) simulations, challenges that come with optimizing our design to increase the wavelength range, initial tests on our design of fabricated 10 µ m KIDs, and theoretical NEP calculations.
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To better understand proteasomal degradation of nuclear proteins and viral antigens we studied mutated forms of influenza virus nucleoprotein (NP) that misfold and are rapidly degraded by proteasomes. In the presence of proteasome inhibitors, mutated NP (dNP) accumulates in highly insoluble ubiquitinated and nonubiquitinated species in nuclear substructures known as promyelocytic leukemia oncogenic domains (PODs) and the microtubule organizing center (MTOC). Immunofluorescence revealed that dNP recruits proteasomes and a selective assortment of molecular chaperones to both locales, and that a similar (though less dramatic) effect is induced by proteasome inhibitors in the absence of dNP expression. Biochemical evidence is consistent with the idea that dNP is delivered to PODs/MTOC in the absence of proteasome inhibitors. Restoring proteasome activity while blocking protein synthesis results in disappearance of dNP from PODs and the MTOC and the generation of a major histocompatibility complex class I-bound peptide derived from dNP but not NP. These findings demonstrate that PODs and the MTOC serve as sites of proteasomal degradation of misfolded dNP and probably cellular proteins as well, and imply that antigenic peptides are generated at one or both of these sites.
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Presentación de Antígeno , Antígenos Virales/metabolismo , Centrosoma/metabolismo , Cisteína Endopeptidasas/metabolismo , Complejos Multienzimáticos/metabolismo , Nucleoproteínas , Proteínas del Núcleo Viral/metabolismo , Presentación de Antígeno/efectos de los fármacos , Antígenos Virales/química , Antígenos Virales/genética , Antígenos Virales/inmunología , Canavanina/farmacología , Centrosoma/efectos de los fármacos , Centrosoma/enzimología , Inhibidores Enzimáticos/farmacología , Técnica del Anticuerpo Fluorescente , Antígenos de Histocompatibilidad Clase I/química , Antígenos de Histocompatibilidad Clase I/genética , Antígenos de Histocompatibilidad Clase I/inmunología , Antígenos de Histocompatibilidad Clase I/metabolismo , Humanos , Leupeptinas/farmacología , Chaperonas Moleculares/metabolismo , Mutación , Proteínas de la Nucleocápside , Orthomyxoviridae , Concentración Osmolar , Fragmentos de Péptidos/química , Fragmentos de Péptidos/genética , Fragmentos de Péptidos/inmunología , Fragmentos de Péptidos/metabolismo , Complejo de la Endopetidasa Proteasomal , Biosíntesis de Proteínas , Conformación Proteica/efectos de los fármacos , Pliegue de Proteína , Solubilidad , Células Tumorales Cultivadas , Ubiquitinas/metabolismo , Proteínas del Núcleo Viral/química , Proteínas del Núcleo Viral/genética , Proteínas del Núcleo Viral/inmunologíaRESUMEN
Cell cultures of crop plants provide new opportunities to recover induced mutations likely to increase crop yield. Approaches include regulating respiration to conserve carbon fixed by photosynthesis, and increasing the nutritive value of seed protein. They depend on devising selecting conditions which only desired mutant cells can survive. Protoplast fusion offers some promise of tapping sources of genetic variation now unavailable because of sterility barriers between species and genera. Difficulties in regenerating cell lines from protoplasts, and plants from cells, still hamper progress but are becoming less severe. Recombinant DNA techniques may allow detection and selection of bacterial cell lines carrying specific DNA sequences. Isolation and amplification of crop plant genes could then lead to ways of transforming plants that will be useful to breeders.
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Hypovirulence in Endothia parasitica is caused by a cytoplasmic determinant that is transferred by hyphal anastomosis in host tissue and in culture. Transmission of this determinant affects the virulence of the fungus to the extent that host invasion by previously virulent isolates is limited.
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The human genome is thought to harbor 50,000 to 100,000 genes, of which about half have been sampled to date in the form of expressed sequence tags. An international consortium was organized to develop and map gene-based sequence tagged site markers on a set of two radiation hybrid panels and a yeast artificial chromosome library. More than 16,000 human genes have been mapped relative to a framework map that contains about 1000 polymorphic genetic markers. The gene map unifies the existing genetic and physical maps with the nucleotide and protein sequence databases in a fashion that should speed the discovery of genes underlying inherited human disease. The integrated resource is available through a site on the World Wide Web at http://www.ncbi.nlm.nih.gov/SCIENCE96/.
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Mapeo Cromosómico , Genoma Humano , Proyecto Genoma Humano , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Línea Celular , Cromosomas Artificiales de Levadura , Redes de Comunicación de Computadores , ADN Complementario/genética , Bases de Datos Factuales , Expresión Génica , Marcadores Genéticos , Humanos , Familia de Multigenes , ARN Mensajero/genética , Homología de Secuencia de Ácido Nucleico , Lugares Marcados de SecuenciaRESUMEN
A map of 30,181 human gene-based markers was assembled and integrated with the current genetic map by radiation hybrid mapping. The new gene map contains nearly twice as many genes as the previous release, includes most genes that encode proteins of known function, and is twofold to threefold more accurate than the previous version. A redesigned, more informative and functional World Wide Web site (www.ncbi.nlm.nih.gov/genemap) provides the mapping information and associated data and annotations. This resource constitutes an important infrastructure and tool for the study of complex genetic traits, the positional cloning of disease genes, the cross-referencing of mammalian genomes, and validated human transcribed sequences for large-scale studies of gene expression.
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Cromosomas Humanos/genética , Genoma Humano , Mapeo Físico de Cromosoma , Animales , Etiquetas de Secuencia Expresada , Expresión Génica , Marcadores Genéticos , Proyecto Genoma Humano , Humanos , Internet , Ratas , Lugares Marcados de SecuenciaRESUMEN
We examined the roles of the Drosophila Gq alpha proteins (DGq) in the phototransduction pathway. The DGq proteins immunolocalized to the ocelli and all eight retinular photoreceptor cell rhabdomeres. An affinity-purified anti-DGq alpha immunoglobulin blocked the light-dependent GTP hydrolysis activity associated with Drosophila head membranes in vitro, suggesting that rhodopsin stimulated DGq. Dominantly active DGq1 mutants exhibited a light-independent GTPase activity and abnormal electrophysiological light responses, such as reduced retinal sensitivity and slow response kinetics compared with wild-type flies. Dominant DGq2 mutants exhibited a light-independent GTPase activity with normal electrophysiological light responses. Retinas of double mutants of DGq1, but not DGq2, with the light-dependent retinal degeneration mutant rdgB degenerated even in the dark. DGq1 stimulation of rdgB retinal degeneration in the dark was norpA-dependent. These results indicate that DGq1 mediates the stimulation by light-activated rhodopsin of the norpA-encoded phospholipase C in the visual transduction cascade.
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Proteínas de Drosophila , GTP Fosfohidrolasas/genética , Proteínas de Unión al GTP/fisiología , Células Fotorreceptoras de Invertebrados/fisiología , Fosfolipasas de Tipo C , Visión Ocular/fisiología , Empalme Alternativo , Animales , Secuencia de Bases , Cartilla de ADN/química , Drosophila melanogaster , Electrofisiología , Genes Dominantes , Genes de Insecto , Técnicas Inmunológicas , Luz , Datos de Secuencia Molecular , Fosfatidilinositol Diacilglicerol-Liasa , Fosfolipasa C beta , Hidrolasas Diéster Fosfóricas/fisiología , Retina/fisiología , Degeneración Retiniana/fisiopatologíaRESUMEN
This revised Clinical Guideline in Paediatric Dentistry replaces the previously published sixth guideline (Fayle SA. Int J Paediatr Dent 1999; 9: 311-314). The process of guideline production began in 1994, resulting in first publication in 1997. Each guideline has been circulated widely for consultation to all UK consultants in paediatric dentistry, council members of the British Society of Paediatric Dentistry (BSPD), and to people of related specialities recognized to have expertise in the subject. The final version of this guideline is produced from a combination of this input and thorough review of the published literature. The intention is to encourage improvement in clinical practice and to stimulate research and clinical audit in areas where scientific evidence is inadequate. Evidence underlying recommendations is scored according to the SIGN classification and guidelines should be read in this context. Further details regarding the process of paediatric dentistry guideline production in the UK is described in the Int J Paediatr Dent 1997; 7: 267-268.