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1.
Nucleic Acids Res ; 35(Database issue): D595-8, 2007 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17151082

RESUMEN

The Hedgehog Signaling Pathway Database is a curated repository of information pertaining to the Hedgehog developmental pathway. It was designed to provide centralized access to a wide range of relevant information in an organism-agnostic manner. Data are provided for all genes and gene targets known to be involved in the Hh pathway across various organisms. The data provided include DNA and protein sequences as well as domain structure motifs. All known human diseases associated with the Hh pathway are indexed including experimental data on therapeutic agents and their molecular targets. Hh researchers will find useful information on relevant protocols, tissue cell lines and reagents used in current Hh research projects. Curated content is also provided for publications, grants and patents relating to the Hh pathway. The database can be accessed at http://www.hedgehog.sfsu.edu.


Asunto(s)
Bases de Datos Genéticas , Proteínas Hedgehog/fisiología , Transducción de Señal , Animales , Genes , Enfermedades Genéticas Congénitas/genética , Humanos , Internet , Ratones , Ratas , Transducción de Señal/genética , Interfaz Usuario-Computador
2.
Rev Sci Instrum ; 87(11): 11D802, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27910485

RESUMEN

Sixty-four neutral density filters constructed of metal plates with 88 apertures of varying diameter have been radiographed with a soft x-ray source and CCD camera at National Security Technologies, Livermore. An analysis of the radiographs fits the radial dependence of the apertures' image intensities to sigmoid functions, which can describe the rapidly decreasing intensity towards the apertures' edges. The fitted image intensities determine the relative attenuation value of each filter. Absolute attenuation values of several imaged filters, measured in situ during calibration experiments, normalize the relative quantities which are now used in analyses of neutron spectrometer data at the National Ignition Facility.

3.
Rev Sci Instrum ; 87(7): 073706, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27475564

RESUMEN

A multi-wavelength, high contrast contact radiography system has been developed to characterize density variations in ultra-low density aerogel foams. These foams are used to generate a ramped pressure drive in materials strength experiments at the National Ignition Facility and require precision characterization in order to reduce errors in measurements. The system was used to characterize density variations in carbon and silicon based aerogels to ∼10.3% accuracy with ∼30 µm spatial resolution. The system description, performance, and measurement results collected using a 17.8 mg/cc carbon based JX-6 (C20H30) aerogel are discussed in this manuscript.

4.
Mech Dev ; 88(2): 229-32, 1999 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-10534621

RESUMEN

We constructed green fluorescent protein (GFP)-expressing balancer chromosomes for each of the three major chromosomes of Drosophila melanogaster. Expression of GFP in these chromosomes is driven indirectly by a Kruppel (Kr) promoter, via the yeast GAL4-UAS regulatory system. GFP fluorescence can be seen in embryos as early as the germ band extension stage, and can also be seen in larvae, pupae, and adults. We show the patterns of GFP expression of these balancers and demonstrate the use of the balancers to identify homozygous progeny.


Asunto(s)
Cromosomas/genética , Drosophila melanogaster/genética , Proteínas Luminiscentes/genética , Proteínas Represoras , Animales , Proteínas de Unión al ADN/genética , Proteínas de Drosophila , Drosophila melanogaster/embriología , Drosophila melanogaster/crecimiento & desarrollo , Embrión no Mamífero , Femenino , Regulación del Desarrollo de la Expresión Génica , Proteínas Fluorescentes Verdes , Factores de Transcripción de Tipo Kruppel , Masculino , Regiones Promotoras Genéticas , Factores de Transcripción/genética
5.
J Bone Joint Surg Br ; 57(3): 297-301, 1975 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-1158941

RESUMEN

The incidence and prognostic significance of fractures of acrylic cement related to the stem of a femoral head prosthesis in total hip replacement are examined. These fractures are demonstrated when the cement has been rendered radio-opaque by the addition of barium sulphate. One and a half percent of the radiographs of 6,649 patients showed these fractures, which were sometimes associated with subsidence of the prosthesis. Fracture of the cement was usually evident at the six-month post-operative review, if it occurred at all. This radiological complication was devoid of symptoms in the majority of cases and tended to occur in patients with excellent functional recovery. In a minority of patients pain in the thigh during the first six months seemed likely to be explained by this fracture. Slight subsidence of the prosthesis in the cement bed appeared to result in a new and final position of stability. The prognosis was very good; only when separation of the fracture exceeded about 4 millimetres was the prognosis doubtful, in which case a chronic deep infection might be suspected. Possible mechanical and structural causes of fracture of the cement are discussed.


Asunto(s)
Cementos para Huesos , Cabeza Femoral , Articulación de la Cadera , Prótesis Articulares , Anciano , Artroplastia , Sulfato de Bario , Peso Corporal , Femenino , Cabeza Femoral/diagnóstico por imagen , Humanos , Masculino , Pronóstico , Radiografía , Factores de Tiempo
6.
J Bone Joint Surg Br ; 72(1): 41-5, 1990 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-2298793

RESUMEN

A total of 138 revision hip arthroplasties in 134 patients, all operated upon by one surgeon, were followed for an average of 7.4 years. The overall results were reasonable, with good to excellent Mayo hip scores in 62% and little or no pain in 86%. These results were independent of body weight, age, primary diagnosis and type of arthroplasty used. The incidence of radiological loosening was alarming, though comparable to that found in other series. Our findings indicate that it may be wise to replace both components even when, after careful assessment before and during operation, one of them seems to be securely fixed.


Asunto(s)
Prótesis de Cadera , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Seguimiento , Articulación de la Cadera/diagnóstico por imagen , Articulación de la Cadera/cirugía , Humanos , Métodos , Persona de Mediana Edad , Cuidados Posoperatorios , Complicaciones Posoperatorias , Falla de Prótesis , Radiografía , Reoperación
8.
Arq. bras. med. vet. zootec ; 66(6): 1681-1686, 12/2014.
Artículo en Portugués | LILACS | ID: lil-735785

RESUMEN

O diagnóstico da úlcera gastroesofágica (UGE) é fundamental para que se tente a recuperação dos afetados, entretanto há grande dificuldade na sua realização de forma precisa. Modernos endoscópios são ferramentas importantes nesse sentido e podem ser usados para determinar em que fase da criação a ulceração ocorre. A bactéria Helicobacter tem sido associada à UGE e gerado perdas econômicas. Tendo em vista que poucos trabalhos têm sido realizados para identificação do problema precocemente, este estudo teve como objetivo detectar as lesões relacionando-as, ou não, com a bactéria Helicobacter spp., mediante análises macroscópica e histopatológica de amostras colhidas por meio da gastroscopia. Foram utilizados 20 animais de ambos os sexos, pesando entre 22 e 26kg e com 65 dias de idade. O aparelho utilizado foi um gastrovideoscópio da marca Karl Storz, modelo 1380NKS. Foram colhidas amostras das regiões anatômicas aglandular (quadrilátero esofágico) e glandular (cárdica, fúndica e pilórica) para o teste ultrarrápido da urease e para as avaliações histopatológicas e imuno-histoquímicas. Onze animais apresentaram lesões na região aglandular à endoscopia, e microscopicamente 15 animais apresentaram paraqueratose. Em 18 animais, foram observadas alterações em pelo menos uma das três regiões glandulares. As lesões foram maiores na região cárdica, seguida da antral e da fúndica. Em relação ao teste ultrarrápido da urease, sete animais foram negativos nas quatro regiões, e 13 positivos em pelo menos uma delas. Em relação à imuno-histoquímica (IHQ), 10 animais foram negativos em todas as regiões e 10 foram positivos em pelo menos uma delas. Os achados pré-ulcerativos não demonstraram relação com o Helicobacter spp., que apresenta caráter saprofítico e oportunista confirmado pela sua imunomarcação em áreas sem lesão...


Gastroesophageal ulcer (GEU) diagnosis is fundamental for the treatment and recovery of the affected animal stock. GEU is a condition affecting animals, resulting in depletion of animal stock and subsequent economic losses. Helicobacter spp. have been associated with GEU. Modern endoscopes are important for detecting the stage of the breeding process at which the ulceration occurs. However, few studies regarding early detection of GEU have been conducted. Therefore, we aimed to identify whether GEU lesions were related to Helicobacter spp. infection, using gastroscopy as a diagnostic technique for macroscopic and histopathological analyses. Twenty piglets (both male and female) with a mean age of 65 days were included (weight, 22-26 kg). We used a Karl Storz Gastrovideoscope (model 1380NKS). Samples from nonglandular and glandular (cardia, fundus, and pylorus) regions were collected for the ultra-rapid urease test and for histopathological and immunohistochemical (IHC) evaluations. Eleven animals showed macroscopic lesions in the nonglandular region during endoscopy, and 15 animals showed parakeratosis on histological analysis. Lesions in at least 1 glandular region were observed in 18 animals. The lesions were bigger in the cardiac region, followed by those in the antrum and the fundus. Regarding the ultra-rapid urease test, 7 animals were negative in all 4 regions and 13 were positive in at least 1 region. On IHC, 10 animals were negative in all 4 regions and 10 were positive in at least 1 region. However, pre-ulcerative findings were not correlated with Helicobacter spp. infection in the present study. The positive IHC findings for Helicobacter spp in regions without ulcerative lesions suggest its saprophytic and opportunistic nature...


Asunto(s)
Animales , Enfermedades del Esófago/veterinaria , Esofagitis/veterinaria , Helicobacter , Porcinos/lesiones , Gastroscopía/veterinaria , Inmunohistoquímica/veterinaria , Enfermedades de los Porcinos
9.
Phys Rev Lett ; 95(21): 215004, 2005 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-16384150

RESUMEN

The first hohlraum experiments on the National Ignition Facility (NIF) using the initial four laser beams tested radiation temperature limits imposed by plasma filling. For a variety of hohlraum sizes and pulse lengths, the measured x-ray flux shows signatures of filling that coincide with hard x-ray emission from plasma streaming out of the hohlraum. These observations agree with hydrodynamic simulations and with an analytical model that includes hydrodynamic and coronal radiative losses. The modeling predicts radiation temperature limits with full NIF (1.8 MJ), greater, and of longer duration than required for ignition hohlraums.

10.
S Afr Med J ; 49(32): 1299-302, 1975 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-1154197

RESUMEN

A description is given of the normal radiological appearances of the Charnley total hip arthroplasty. This is followed by a description of the radiological assessment of the complications that may be associated with this operation.


Asunto(s)
Artroplastia , Cadera/diagnóstico por imagen , Complicaciones Posoperatorias/diagnóstico por imagen , Acetábulo , Anciano , Artritis Reumatoide/cirugía , Cementos para Huesos , Femenino , Cabeza Femoral , Luxación de la Cadera/diagnóstico por imagen , Articulación de la Cadera , Humanos , Prótesis Articulares , Movimiento (Física) , Pelvis , Radiografía , Estrés Mecánico , Infección de la Herida Quirúrgica/diagnóstico por imagen
11.
Clin Orthop Relat Res ; (211): 108-15, 1986 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-3769249

RESUMEN

Extension of infection down the medulla of the femur to the supracondylar region may occur in cases of chronic infected total hip arthroplasty. Because this cannot always be identified before operation, the femur should be reamed and flushed proximally from the lateral condyle in all cases where there is suspicion of infection around the femoral component. Where infection is unequivocal and extensive, a period of irrigation and suction drainage is advisable before final total hip arthroplasty. After the prosthesis has been inserted in either one or two stages, it is wise not to rely on antibiotic cement mixtures alone but to monitor the bacterial flora and prescribe local antibiotic therapy accordingly.


Asunto(s)
Antibacterianos/uso terapéutico , Infecciones Bacterianas/tratamiento farmacológico , Prótesis de Cadera , Infección de la Herida Quirúrgica/terapia , Infecciones Bacterianas/complicaciones , Infecciones Bacterianas/diagnóstico por imagen , Cementos para Huesos/uso terapéutico , Desbridamiento , Estudios de Seguimiento , Humanos , Falla de Prótesis , Radiografía
12.
Cell ; 103(2): 189-92, 2000 Oct 13.
Artículo en Inglés | MEDLINE | ID: mdl-11057892

RESUMEN

Finding that peripodial cells in wing and eye imaginal discs are essential for the growth and patterning of the separate layer of disc cells now opens the study of interacting cell layers to the powerful developmental genetic techniques with which the Drosophila system is blessed. We can anticipate that future work will identify how such interactions contribute to patterning and how the mechanisms and processes that are involved are conserved in vertebrates. We can also look forward to contributions that this work will make to understand-ing the role of interconnecting cell extensions in such signaling processes. In this minireview, we have noted numerous types of signaling cells in which cellular extensions have been observed. At present, neither the functional nor structural relationship of these related structures is known. It is certainly tempting to suggest that these structures are conduits for signals or that they function as sensors. There is, as yet, no direct experimental evidence for such roles.


Asunto(s)
Tipificación del Cuerpo , Drosophila/embriología , Inducción Embrionaria , Animales
13.
Cell ; 97(5): 599-607, 1999 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-10367889

RESUMEN

Wing imaginal disc cells in Drosophila develop by using information received from a signaling center associated with the anterior/posterior compartment border. We show here that disc cells have thin, actin-based extensions (cytonemes) that project to this signaling center. Cytonemes can be induced when cells from the lateral flanks of a wing disc are cultured next to cells from the A/P border or next to a source of fibroblast growth factor. Mouse limb bud cells also grow projections during a brief culture period, indicating that cytonemes are an attribute of both vertebrate and invertebrate cells. We suggest that cytonemes may be responsible for some forms of long-range cell-cell communication.


Asunto(s)
Actinas/fisiología , Drosophila/embriología , Embrión no Mamífero/fisiología , Animales , Tipificación del Cuerpo , Comunicación Celular , Drosophila/crecimiento & desarrollo , Factores de Crecimiento de Fibroblastos/fisiología , Larva , Esbozos de los Miembros , Ratones , Técnicas de Cultivo de Órganos , Transducción de Señal , Alas de Animales/embriología , Alas de Animales/crecimiento & desarrollo
14.
Dev Genes Evol ; 208(1): 28-36, 1998 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-9518522

RESUMEN

Using intracellular lineage tracers to study the main neurogenic lineage (N lineage) of the glossiphoniid leech embryo, we have characterized events leading from continuous columns of segmental founder cells (nf and ns primary blast cells) to discrete, segmentally iterated ganglia. The separation between prospective ganglia was first evident as a fissure between the posterior boundary of nf- and the anterior boundary of ns-derived progeny. We also identified the sublineages of nf-derived cells that contribute parallel stripes of cells to each segment. These stripes of cells project ventrolaterally from the dorsolateral margin of each nascent ganglion to the ventral body wall. The position and orientation of the stripes suggests that they play a role in forming the posterior segmental nerve; they are not coincident with the ganglionic boundary, and they form well after the separation of ganglionic primordia. Previous work has shown that cells in the anterior stripe express the leech engrailed-class gene. Thus, in contrast to the role of cells expressing engrailed in Drosophila, the stripes of N-derived cells expressing an engrailed-class gene in leech do not seem to play a direct role in segmentation or segment polarity.


Asunto(s)
Ganglios de Invertebrados/anatomía & histología , Ganglios de Invertebrados/embriología , Sanguijuelas/anatomía & histología , Sanguijuelas/embriología , Animales , Sistema Nervioso Central/anatomía & histología , Sistema Nervioso Central/embriología , Células Clonales , Morfogénesis
15.
Mol Cell ; 6(2): 479-85, 2000 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10983993

RESUMEN

Drosophila Hedgehog (Hh) is secreted by Posterior (P) compartment cells and induces Anterior (A) cells to create a developmental organizer at the AP compartment border. Hh signaling converts Fused (Fu) to a hyperphosphorylated form, Fu*. We show that A border cells of wing imaginal discs contain Fu*. Unexpectedly, P cells also produce Fu*, in a Hh-dependent and Ptc-independent manner. Increasing Ptc, the putative Hh receptor expressed specifically by A cells, reduced Fu*. These results are consistent with proposals that Ptc downregulates Hh signaling and suggest that a receptor other than Ptc mediates Hh signaling in P cells of imaginal discs. We conclude that Hh signals in these P cells and that the outputs of the pathway are blocked by transcriptional repression.


Asunto(s)
Proteínas de Drosophila , Drosophila melanogaster/fisiología , Proteínas de Insectos/fisiología , Proteínas Serina-Treonina Quinasas/fisiología , Transducción de Señal/fisiología , Animales , Drosophila melanogaster/genética , Regulación de la Expresión Génica , Proteínas Hedgehog , Proteínas de Insectos/genética , Eliminación de Secuencia , Transcripción Genética , Alas de Animales/citología , Alas de Animales/crecimiento & desarrollo
16.
Cell ; 89(7): 1043-53, 1997 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-9215627

RESUMEN

Cell-cell communication at anterior/posterior compartment borders in Drosophila involves Hedgehog (Hh), a protein secreted by posterior cells, and Cubitus interruptus (Ci), a protein in the Hh response pathway in anterior cells. Although Ci is thought to have roles as a transcription factor repressing hh expression and activating target genes, it localizes in the cytoplasm of anterior cells. We report here the identification of a domain that tethers Ci in the cytoplasm and show that in some anterior cells, Ci is cleaved to generate a form that lacks the tethering domain. This form translocates to the nucleus where it represses hh and other target genes. Hh inhibits proteolysis of Ci, and we suggest that this inhibition leads to the observed patterns of expression of key target genes at the compartment border.


Asunto(s)
Proteínas de Unión al ADN/metabolismo , Proteínas de Drosophila , Drosophila/fisiología , Proteínas de Insectos/metabolismo , Proteínas Represoras/metabolismo , Animales , Núcleo Celular/química , Núcleo Celular/metabolismo , Células Cultivadas , Citoplasma/química , Citoplasma/metabolismo , Proteínas de Unión al ADN/química , Drosophila/química , Drosophila/embriología , Embrión no Mamífero/química , Embrión no Mamífero/fisiología , Regulación del Desarrollo de la Expresión Génica/fisiología , Proteínas Hedgehog , Proteínas de Insectos/genética , Proteínas de la Membrana/metabolismo , Estructura Terciaria de Proteína , Receptores de Superficie Celular/metabolismo , Transducción de Señal/fisiología , Factores de Transcripción , Dedos de Zinc/fisiología
17.
Phys Rev Lett ; 93(6): 065002, 2004 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-15323638

RESUMEN

We present measurements of the absolute albedos of hohlraums made from gold or from high-Z mixtures. The measurements are performed over the range of radiation temperatures (70-100 eV) expected during the foot of an indirect-drive temporally shaped ignition laser pulse, where accurate knowledge of the wall albedo (i.e., soft x-ray wall reemission) is most critical for determining capsule radiation symmetry. We find that the gold albedo agrees well with calculations using the supertransition array opacity model, potentially providing additional margin for inertial confinement fusion ignition.

19.
Arq. ciênc. vet. zool. UNIPAR ; 7(1): 11-17, jan.-jun. 2004. ilus, graf
Artículo en Portugués | LILACS | ID: lil-418100

RESUMEN

Os AINEs são drogas amplamente utilizadas para o alívio da dor de origem musculoesquelética e em procedimentos cirúrgicos, principalmente ortopédicos,, no pré, trans e pós-operatório. Os efeitos colaterais dos AINEs resultam de sua ação inibitória sobre a cicloxigenase, destacando sua atuação sobre o aparelho digestório, tornando o exame gastroscópico de grande valia para uma avaliação intraluminal direta. Foram utilizados seis cães, sendo um mantido como controle, sem raça definida, três machos e três fêmeas e idades variadas onde se dividiu o experimento em três módulos: Módulo 1: flunixim meglumine na dosagem de 1,0 mg/kg a cada 24 horas por 5 dias; Módulo 2: piroxican na dosagem de 0,3 mg/kg a cada 48 horas, perfazendo um total de 3 aplicações; e, Módulo 3: cetoprofeno na dosagem de 1,0 mg/kg com intervalo de 24 horas durante 5 dias. Os pacientes foram submetidos a exame endoscópico no 1º, 4º, 6º, 8º, 10º dia. Nas três drogas testadas foram observadas lesões gástricas que variaram de gastrite leve até ulceração, sendo o piroxican o que demonstrou maior potencial ulcerogênico. Clinicamente não foi observada qualquer alteração. O exame endoscópico se mostrou eficaz, preciso e com grande acuidade para o diagnóstico das alterações gástricas provocadas pelas drogas testadas.


Asunto(s)
Animales , Antiinflamatorios no Esteroideos , Perros , Fenómenos Fisiológicos del Sistema Digestivo , Gastroscopía/métodos
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