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1.
Soc Networks ; 66: 114-124, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34054204

RESUMEN

Self-reported social network analysis studies are often complex and burdensome, both during the interview process itself, and when conducting data management following the interview. Through funding obtained from the National Institute on Drug Abuse (NIDA/NIH), our team developed the Network Canvas suite of software - a set of complementary tools that are designed to simplify the collection and storage of complex social network data, with an emphasis on usability and accessibility across platforms and devices, and guided by the practical needs of researchers. The suite consists of three applications: Architect: an application for researchers to design and export interview protocols; Interviewer: a touch-optimized application for loading and administering interview protocols to study participants; and Server: an application for researchers to manage the interview deployment process and export their data for analysis. Together, they enable researchers with minimal technological expertise to access a complete research workflow, by building their own network interview protocols, deploying these protocols widely within a variety of contexts, and immediately attaining the resulting data from a secure central location. In this paper, we outline the critical decisions taken in developing this suite of tools for the network research community. We also describe the work which guides our decision-making, including prior experiences and key discovery events. We focus on key design choices, taken for theoretical, philosophical, and pragmatic reasons, and outline their strengths and limitations.

2.
Ann R Coll Surg Engl ; 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38746984

RESUMEN

INTRODUCTION: Therapeutic mammaplasty (TM) facilitates large tumour resection while maintaining optimal aesthetic outcome. It carries higher wound complication risks, which may delay adjuvant therapy initiation. Whether this delay affects oncological outcome requires evaluation. METHODS: Data were collected for consecutive patients receiving TM at the Leeds breast unit (2009-2017). A prospectively maintained database was used to determine tumour characteristics, wound complication rates, receipt of adjuvant therapy and breast cancer recurrence or death. RESULTS: In total 112 patients (median age of 54 years) underwent 114 TM procedures. The most common histological subtypes were invasive ductal carcinoma (61.4%), invasive lobular carcinoma (13.2%) and ductal carcinoma in situ (13.2%). Of the patients, 88.2% had oestrogen receptor-positive cancer and 14% had human epidermal growth factor receptor-positive cancer; 26.3% had multifocal cancer. The median tumour size was 30mm. The median Nottingham Prognostic Index was 4.2. The local recurrence rate was 3.5% (median follow-up of 8.6 years). The 5- and 10-year disease-free survival (DFS) was 88.5% and 83.5%, and the equivalent overall survival (OS) rates were 94% and 83.5%. Wound complication rate was 23.6% (n=27), the commonest being wound infection (11.4%; n=13) and T-junction wound breakdown (10.5%; n=12). The median time to adjuvant therapy was 72 days (interquartile range [IQR] 56-90) for patients with wound complications, and 51 days (IQR 42-58) for those without. However, this delay did not affect DFS or OS (log-rank test; p=0.58 and p=0.94, respectively). This was confirmed on Cox regression analysis. CONCLUSION: Our study finding demonstrates that although wound complications after TM leads to a modest delay to adjuvant therapy, the long-term oncological outcomes were comparable with those in patients without wound complications.

3.
Phys Rev Lett ; 110(19): 196001, 2013 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-23705720

RESUMEN

The effect of nanoparticles (NP) on chain dimensions in polymer melts has been the source of considerable theoretical and experimental controversy. We exploit our ability to ensure a spatially uniform dispersion of 13 nm silica NPs miscible in polystyrene melts, together with neutron scattering, x-ray scattering, and transmission electron microscopy, to show that there is no measurable change in the polymer size in miscible mixtures, regardless of the relative sizes of the chains and the nanoparticles, and for NP loadings as high as 32.7 vol%. Our results provide a firm basis from which to understand the properties of polymer nanocomposites.


Asunto(s)
Nanocompuestos/química , Nanopartículas/química , Poliestirenos/química , Dióxido de Silicio/química , Microscopía Electrónica de Transmisión , Conformación Molecular , Difracción de Neutrones , Dispersión del Ángulo Pequeño , Difracción de Rayos X
4.
Int Arch Occup Environ Health ; 86(1): 1-15, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22915144

RESUMEN

PURPOSE: The aim of this study was to summarize and evaluate the current scientific literature on stress and strain on seafarers on board as defined by maritime field surveys. METHODS: Using a systematic review, 109 studies on the stress and strain experienced by seafarers were identified for the period January 1990 to January 2012. RESULTS: Only 13 of the identified maritime studies were conducted as field studies, and in 10 of these studies, the focus was on the watch system and/or on fatigue. According to the study results, sleepiness tends to be stronger in the 2-watch system than in the 3-watch system (particularly between 4:00 and 6:00 a.m.). Occasional short sleep episodes appear to provide adequate recovery. Fatigue does not appear to depend on the seafarers' age and is often associated with poor sleep quality; noise and night shifts are also considered to contribute to fatigue. Stress among the seafarers was primarily recorded in sleep diaries (9 times) and with devices for measuring physical activity (4 times). As a rule, a questionnaire was used to assess the strain on the crew on board; 7 studies also additionally recorded biometrical parameters. Only in 6 cases were several groups with different ranks on board investigated. CONCLUSION: The conducted literature review makes it clear that most maritime field studies have focused on fatigue and watch systems in the shipping industry--in each case as univariate parameters. Thus, scientific field studies with comprehensive multivariate stress and strain analyses on board are required.


Asunto(s)
Fatiga/psicología , Navíos , Estrés Psicológico , Humanos , Encuestas y Cuestionarios
5.
Laryngorhinootologie ; 92(8): 536-40, 2013 Aug.
Artículo en Alemán | MEDLINE | ID: mdl-23568584

RESUMEN

The spectrum of ENT-diseases can differ widely among emergency departments (ED) of different geographic regions. Especially in terms of head and neck trauma a higher number of injuries can be expected in large cities due to alcohol related violence.The ED of a large hospital situated in the center of Hamburg Germany was analysed for ENT-emergency treatments in 2011 retrospectively. Beside usual patient statistics, the study focused on alcohol related injuries with an ENT-surgeon involved. All data were compared to reports by other EDs in Germany and alcohol related costs were approximated for initiation of prevention programs in the future.2 339 ENT-patients were admitted to the ED. 19% of all patients used an ambulance whereas 80% reached the ED by private transportation. The majority of patients were between 21 and 30 years of age. For 143 of all trauma cases alcohol involvement was documented. Subanalysis revealed male dominance and a high use of ambulance transportation.The high number of traumata differs considerably from other ENT studies. One reason is the hospital's close proximity to all time party districts like "Reeperbahn" and the "Port of Hamburg". In those areas high amounts of alcohol ingestion takes place leading to more injuries at the head- and neck region. Theoretically financial resources would be plenty after the initiation of those programs as the severe costs for alcohol related medical treatment would decline.


Asunto(s)
Intoxicación Alcohólica/complicaciones , Alcoholismo/complicaciones , Traumatismos Craneocerebrales/terapia , Servicio de Urgencia en Hospital , Traumatismos del Cuello/terapia , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Intoxicación Alcohólica/epidemiología , Alcoholismo/epidemiología , Niño , Traumatismos Craneocerebrales/diagnóstico , Traumatismos Craneocerebrales/epidemiología , Traumatismos Craneocerebrales/etiología , Estudios Transversales , Grupos Diagnósticos Relacionados , Servicio de Urgencia en Hospital/estadística & datos numéricos , Femenino , Alemania , Hospitales Urbanos/estadística & datos numéricos , Humanos , Masculino , Persona de Mediana Edad , Traumatismos del Cuello/diagnóstico , Traumatismos del Cuello/epidemiología , Traumatismos del Cuello/etiología , Admisión del Paciente/estadística & datos numéricos , Estudios Retrospectivos , Factores de Riesgo , Medio Social , Centros Traumatológicos/estadística & datos numéricos , Revisión de Utilización de Recursos , Adulto Joven
6.
Skeletal Radiol ; 41(7): 831-4, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21997671

RESUMEN

INTRODUCTION: Magnetic resonance imaging on 3 Tesla (3T MRI) with arthroscopic correlation has proven to adequately identify the anteromedial bundle (AMB) and posterolateral bundle (PLB) in cadaver knees. The purpose of this study was to describe the depiction of ACL bundle anatomy on 3T MRI in daily practice. METHODS: In a retrospective cohort study, we included 50 consecutive patients who underwent standard 3T MRI of the knee and had an intact ACL. Two musculoskeletal radiologists independently reviewed all scans for depiction of ACL bundle anatomy using standardized forms. Descriptive statistics were used. RESULTS: Twenty-three right knees (46%) and 27 left knees (54%) were included in the study. Mean age of the patients was 35 years (range 12 to 68 years); 37 patients were male (74%). ACL bundle anatomy was best depicted in the axial plane in 44 knees (88%) and in the coronal plane in six knees (12%). Two bundles were seen in 47 knees (94%). The AMB was completely seen in 45 knees (90%). The PLB was completely seen in 40 knees (80%). Both bundles were completely seen in 37 knees (76%). CONCLUSIONS: The double-bundle anatomy of the ACL is visualized in 94% of patients on 3T MRI. Because of potentially associated clinical benefits, we advocate to report separately on the anteromedial bundle and posterolateral bundle in case of anterior cruciate ligament injury of the knee.


Asunto(s)
Ligamento Cruzado Anterior/anatomía & histología , Imagen por Resonancia Magnética/métodos , Adolescente , Adulto , Anciano , Niño , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Adulto Joven
7.
Euro Surveill ; 17(2)2012 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-22264864

RESUMEN

The 2009 influenza pandemic has introduced the new re-assorted influenza A(H1N1)pdm09 virus which recirculated during the 2010/11 influenza season. Before that season, it was possible to acquire protective immunity either by pandemic or seasonal influenza vaccination against influenza A(H1N1)pdm09 or by natural infection. To obtain data on vaccination coverage and antibody levels in a reference population and to calculate whether or not the herd immunity threshold (HIT, calculated as 33% given an R0 of 1.5) was reached at the beginning of the 2010/11 season we performed a seroprevalence study in November 2010 in Hamburg, Germany. Antibody titres were assessed applying a haemagglutination inhibition test. Vaccination coverage was very low: 14% for pandemic and 11% for seasonal 2010/11 vaccinations. Even in those with underlying risk factors, vaccination coverage was not much higher: 17% for both vaccines. Serological analysis revealed antibody titres of ≥1:10 in 135 of 352 (38%) and of ≥1:40 in 61 of 352 study participants (17%). Specific antibodies were measurable in 26% of those without history of vaccination or natural infection, indicating a high proportion of subclinical and mild influenza disease. Nevertheless, the HIT was not reached, leaving the majority of the population susceptible to influenza A(H1N1)pdm09 and its potential complications.


Asunto(s)
Anticuerpos Antivirales/sangre , Subtipo H1N1 del Virus de la Influenza A/inmunología , Vacunas contra la Influenza/administración & dosificación , Vacunas contra la Influenza/inmunología , Gripe Humana/epidemiología , Adolescente , Adulto , Anciano , Estudios Transversales , Alemania/epidemiología , Pruebas de Inhibición de Hemaglutinación , Humanos , Gripe Humana/prevención & control , Masculino , Persona de Mediana Edad , Pandemias , Prevalencia , Factores de Riesgo , Estaciones del Año , Estudios Seroepidemiológicos , Encuestas y Cuestionarios , Vacunación , Adulto Joven
8.
Nat Cell Biol ; 3(7): E165-7, 2001 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-11433314

RESUMEN

In developmental biology, as in all scientific fields, conceptual advances are tightly coupled to technological innovation. In this review, we trace the evolution of techniques in experimental embryology, from classical ablation to the latest methods utilizing in vivo electroporation, with lens induction as a linking theme.


Asunto(s)
Biología Evolutiva/historia , Ojo/embriología , Animales , Biotecnología/métodos , Biotecnología/tendencias , Historia del Siglo XIX , Historia del Siglo XX , Humanos , Cristalino/embriología
9.
J Cell Biol ; 49(3): 692-701, 1971 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-4997172

RESUMEN

Emetine is a potent inhibitor of protein synthesis in sea urchin embryos. At a concentration of the drug that rapidly inhibits protein synthesis in blastulae by 95%, uridine incorporation into RNA continues for more than 1 hr and presumptive histone messenger RNA is synthesized and transported into the cytoplasm where it is apparently associated with polyribosomes. Possible explanations of this result and its implications for the "informasome" theory of messenger transport in embryonic cells are discussed.


Asunto(s)
Citoplasma/metabolismo , Emetina/farmacología , Proteínas/antagonistas & inhibidores , ARN Mensajero/biosíntesis , ARN/biosíntesis , Aminoácidos , Animales , Transporte Biológico , Isótopos de Carbono , Centrifugación por Gradiente de Densidad , Citoplasma/análisis , ADN/biosíntesis , Equinodermos , Ácido Edético , Electroforesis Discontinua , Embrión no Mamífero/citología , Embrión no Mamífero/metabolismo , Histocitoquímica , Histonas/análisis , Morfogénesis/efectos de los fármacos , Biosíntesis de Proteínas , ARN/análisis , ARN Mensajero/metabolismo , ARN Ribosómico/biosíntesis , Ribosomas/análisis , Ribosomas/metabolismo , Tritio , Uridina/metabolismo
10.
J Cell Biol ; 95(1): 197-204, 1982 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-7142285

RESUMEN

Two sulphated glycoproteins (sgps) of apparent molecular weight (Mr) 180,000 and 150,000, are synthesized by murine PYS and PF HR9 parietal endoderm and Swiss 3T3 cells. The Mr 150,000 sgp has a similar chemical structure to the sulphated glycoprotein, C, synthesized and laid down in Reichert's membrane by mouse embryo parietal endoderm cells (Hogan, B. L.M., A. Taylor, and A.R. Cooper, 1982, Dev. Biol., 90:210-214). Both the Mr 180,000 and 150,000 sgps are deposited in the detergent-insoluble matrix of cultured cells, but they do not apparently undergo any disulphide-dependent intermolecular interactions and are not precursors or products of each other. They contain asparagine-linked oligosaccharides, but these are not the exclusive sites of sulphate labeling. Antiserum raised against the Mr 150,000 sgp C of Reichert's membranes has been used in an immunohistochemical analysis of rat skin. In early foetal and adult skin the antigen is present only in basement membranes, but transiently before and after birth it is also found throughout the upper part of the dermis. This suggests that 150,000 sgp C is at times synthesized by nonepithelial cells and contributes to the extracellular matrix of mesenchymal tissues.


Asunto(s)
Membrana Basal/metabolismo , Espacio Extracelular/fisiología , Glicoproteínas/metabolismo , Animales , Células Cultivadas , Medios de Cultivo , Fibronectinas/metabolismo , Glicoproteínas/genética , Ratones , Peso Molecular , ARN Mensajero/metabolismo , Ratas , Piel/metabolismo , Teratoma/metabolismo
11.
J Cell Biol ; 106(2): 441-50, 1988 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-3339096

RESUMEN

2ar has been identified as a gene inducible by tumor promoters and growth factors in a variety of cultured mouse cell lines (Smith, J. H., and D. T. Denhardt. 1987. J. Cell. Biochem. 34:13-22). Sequence analysis shows that it codes for mouse osteopontin, an RGDS-containing, phosphorylated, sialic acid-rich Ca++-binding protein originally isolated from bone (Oldberg, A., A. Franzen, and D. Heinegard. 1986. Proc. Natl. Acad. Sci. USA. 83:8819-8823; Prince, C. W., T. Oosawa, W. T. Butler, M. Tomana, A. S. Brown, and R. E. Schrohenloer. 1987. J. Biol. Chem. 262:2900-3907.). In this paper we use Northern blot analysis and in situ hybridization to localize expression of 2ar during mouse embryogenesis. 2ar RNA is first detected in developing limb bones and calvaria at 14.5 d p.c., in a population of cells distinct from those expressing SPARC (osteonectin). High levels of 2ar expression are also seen in the bone marrow-derived granulated metrial gland cells of the deciduum and placenta, and in a number of epithelial tissues, including embryonic and postnatal kidney tubules, uterine epithelium and sensory epithelium of the embryonic ear. The temporal and spatial pattern of 2ar expression seen in vivo suggests that the protein plays a wider role than previously realized, in processes which are not confined to bone development.


Asunto(s)
Proteínas Portadoras/genética , Ratones/embriología , Sialoglicoproteínas/genética , Animales , Desarrollo Óseo , Huesos/embriología , Adhesión Celular , Células Cultivadas , Decidua/fisiología , Dexametasona/farmacología , Oído/embriología , Femenino , Factores de Crecimiento de Fibroblastos/farmacología , Regulación de la Expresión Génica/efectos de los fármacos , Riñón/embriología , Riñón/crecimiento & desarrollo , Hibridación de Ácido Nucleico , Osteonectina , Osteopontina , Progesterona/farmacología , ARN Mensajero/genética , Sialoglicoproteínas/fisiología , Distribución Tisular
12.
J Cell Biol ; 120(2): 493-502, 1993 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-8421061

RESUMEN

DVR-6 (BMP-6 or Vgr-1) is a member of the TGF-beta superfamily of polypeptide signaling molecules. In situ hybridization studies have previously shown that DVR-6 RNA is expressed in a variety of cell types in the mouse embryo, but no information has been available on protein localization and biosynthesis. We have produced a polyclonal antibody to the proregion of DVR-6 and used it to localize the protein in whole mount and sectioned embryonic, newborn, and adult mouse tissues. DVR-6 protein is expressed in the mouse nervous system beginning at 9.5 days postcoitum (d.p.c.) and continues through adulthood. A variety of epithelial tissues also produce DVR-6 protein, including the suprabasal layer of the skin, bronchiolar epithelium, and the cornea. Additionally, a stably transfected cell line, BMGE+H/D6c4, is used to study the biosynthesis of DVR-6 protein and evidence is presented for translational regulation of DVR-6 expression.


Asunto(s)
Sustancias de Crecimiento/biosíntesis , Sistema Nervioso/embriología , Biosíntesis de Proteínas , Transcripción Genética , Animales , Proteínas Morfogenéticas Óseas , Bovinos , Células Cultivadas , Embrión de Mamíferos , Desarrollo Embrionario y Fetal , Células Epiteliales , Epitelio/fisiología , Femenino , Glutatión Transferasa/análisis , Glutatión Transferasa/biosíntesis , Glutatión Transferasa/genética , Humanos , Inmunohistoquímica , Glándulas Mamarias Animales/fisiología , Ratones , Sistema Nervioso/citología , Proteínas/análisis , Proteínas/genética , Proteínas Recombinantes de Fusión/análisis , Proteínas Recombinantes de Fusión/biosíntesis , Transfección
13.
J Cell Biol ; 105(1): 473-82, 1987 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-2440898

RESUMEN

In situ hybridization is used to survey the tissue-specific and developmental expression of the cloned mouse gene Sparc, coding for a protein homologous to the bovine Ca++-binding protein, osteonectin. High levels of SPARC RNA are found in osteoblasts and odontoblasts. In addition, high grain counts are associated with a variety of other cell types in the embryo and newborn mouse, including parietal endoderm, deciduum, whisker follicles (connective tissue sheath), peripheral nerve trunk, skin (dermis), and stomach (submucosa). Spatially restricted but high levels of SPARC mRNA are also seen in the adult adrenal glands, testis, and ovary. This pattern of differential gene expression demands a reassessment of the function originally proposed for osteonectin, and predicts a much wider role for the protein in a variety of biological processes.


Asunto(s)
Proteínas Portadoras/biosíntesis , ARN Mensajero/biosíntesis , Glándulas Suprarrenales/metabolismo , Factores de Edad , Animales , Animales Recién Nacidos/metabolismo , Femenino , Regulación de la Expresión Génica , Masculino , Ratones , Ratones Endogámicos CBA , Hibridación de Ácido Nucleico , Especificidad de Órganos , Osteonectina , Ovario/metabolismo , ARN/genética , ARN Complementario , Testículo/metabolismo
14.
Science ; 287(5457): 1427-30, 2000 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-10688781

RESUMEN

Stem cells are currently in the news for two reasons: the successful cultivation of human embryonic stem cell lines and reports that adult stem cells can differentiate into developmentally unrelated cell types, such as nerve cells into blood cells. Both intrinsic and extrinsic signals regulate stem cell fate and some of these signals have now been identified. Certain aspects of the stem cell microenvironment, or niche, are conserved between tissues, and this can be exploited in the application of stem cells to tissue replacement therapy.


Asunto(s)
Diferenciación Celular , División Celular , Células Madre , Animales , Comunicación Celular , Linaje de la Célula , Matriz Extracelular/fisiología , Homeostasis , Humanos , Integrinas/fisiología , Proteínas/fisiología , Células Madre/citología , Células Madre/fisiología , Factores de Transcripción/fisiología
15.
Nanoscale ; 11(5): 2476-2483, 2019 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-30672548

RESUMEN

Highly selective, fast detection of specific lung-cancer biomarkers (CMs) in exhaled human breath is vital to the development of enhanced sensing devices. Today, e-nose is a promising approach for the diagnosis of lung cancer. Nevertheless, considerable challenges to early-stage disease diagnostics still remain: e.g. decrease in sensor sensitivities in the presence of water vapor, sensor drift leading to the inability to calibrate exactly, relatively short sensor lifetimes, and difficulty discriminating between multiple diseases. However, there is a wide scope for breath diagnostics techniques, and all advanced electrodes applicable to e-nose devices will benefit them. Here, we present the promising sensing capabilities of bare multi-layer graphene (MLG) as a proof of concept for advanced e-nose devices and demonstrate its utility for biomolecule discrimination of the most common lung CMs (ethanol, isopropanol, and acetone). We report on a comparative study involving exposure of the three CM solutions on flat MLG (f-MLG) and patterned MLG (p-MLG) electrodes, where the electrical conductivity of p-MLG is significantly increased while applying acetone. Based on sensitivity tests, we demonstrate the ability to monitor the electrical response of graphene electrodes employing graphene of various wettabilities. Specifically, the f-MLG electrode displays almost 2 times higher sheet resistance (30 Ω sq-1) compared to the hydrophilic p-MLG (12 Ω sq-1). We show significant sensitivity to selected specific molecules of pristine f-MLG and p-MLG while applying CM solutions with a 1.4 × 105 ppm concentration. Finally, we show the selectivity of f-MLG and p-MLG-based sensors when exposed to 2.0 × 105 ppm solutions containing different CM combinations. Both sensors were selective in particular to acetone, since the presence of acetone leads to a sheet resistance increase. We demonstrate that an advanced e-nose approach integrated with MLG electrodes has significant potential as a design concept for utilization of molecular detection at variable concentrations such as in early-stage disease diagnosis. This early-stage approach will provide convenient and reusable complex monitoring of CMs compared to typical contact sensors which require target analysis and are limited by disposable measuring. Moreover, further integration of the Internet of Things will introduce advanced e-nose devices as a biotechnological innovation for disease resilience with the potential for commercialization.


Asunto(s)
Técnicas Biosensibles/métodos , Pruebas Respiratorias/métodos , Nariz Electrónica , Grafito/química , Neoplasias Pulmonares/diagnóstico , 2-Propanol/química , Acetona/química , Biomarcadores de Tumor/química , Calibración , Conductividad Eléctrica , Electrodos , Etanol/química , Humanos , Óxidos/química , Oxígeno/química
16.
Curr Opin Genet Dev ; 6(4): 432-8, 1996 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-8791534

RESUMEN

The bone morphogenetic proteins (BMPs) constitute a large family of cytokines related to members of the transforming growth factor-beta superfamily. Recent evidence, in particular from gene targeting experiments in the mouse, indicates that BMPs are required for mesoderm formation and for the development and patterning of many different organ systems. Significant progress has also been made in understanding the role of BMPs in gastrulation and neurulation in Xenopus and in identifying genes regulating BMP expression and components of the downstream signaling pathways. Extracellular modifiers of BMP activity may constitute an opposing morphogenetic system.


Asunto(s)
Proteínas Morfogenéticas Óseas/metabolismo , Desarrollo Embrionario/fisiología , Desarrollo Embrionario y Fetal/fisiología , Factor de Crecimiento Transformador beta/metabolismo , Animales , Proteína Morfogenética Ósea 4 , Proteína Morfogenética Ósea 7 , Proteínas Morfogenéticas Óseas/genética , Extremidades/embriología , Ojo/embriología , Femenino , Regulación del Desarrollo de la Expresión Génica , Humanos , Riñón/embriología , Embarazo , Factor de Crecimiento Transformador beta/genética , Proteínas de Xenopus
17.
Curr Opin Genet Dev ; 4(4): 517-22, 1994 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-7950318

RESUMEN

Embryonic induction is the process by which signals from one cell population change the developmental fate of another. Polypeptides related to growth factors are one group of molecules mediating many inductive events. Recent data on the embryonic expression and function of signaling proteins related to transforming growth factor beta, in both vertebrate and invertebrate systems, have shown that these molecules play important roles in both pattern formation and tissue specification during embryogenesis.


Asunto(s)
Proteínas de Drosophila , Inducción Embrionaria/genética , Regulación del Desarrollo de la Expresión Génica , Factor de Crecimiento Transformador beta/genética , Factor de Crecimiento Transformador beta/metabolismo , Células 3T3 , Animales , Proteínas Morfogenéticas Óseas , Embrión de Pollo , Drosophila/embriología , Genes Reguladores , Hormonas de Insectos/metabolismo , Ratones , Morfogénesis/genética , Proteínas/metabolismo , Transducción de Señal , Xenopus
18.
Curr Opin Genet Dev ; 8(4): 481-6, 1998 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-9729726

RESUMEN

The establishment of branched tubular epithelial structures is critical for the viability of multicellular organisms: the tracheal system in Drosophila and the vertebrate lung being two such structures. Although there are obvious differences in the complexity of these branched organs, many of the underlying mechanisms and genes regulating their development appear to have been evolutionarily conserved.


Asunto(s)
Pulmón/embriología , Animales , Drosophila/embriología , Desarrollo Embrionario y Fetal , Epitelio , Mamíferos , Mesodermo , Sistema Respiratorio/embriología , Transducción de Señal
19.
J Vet Pharmacol Ther ; 31(5): 415-22, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19000260

RESUMEN

The purpose of the study was to assess the pharmacokinetics of liposome-encapsulated (DPPC-C) hydromorphone administered intravenously (IV) or subcutaneously (SC) to dogs. A total of eight healthy Beagles aged 12.13 +/- 1.2 months and weighing 11.72 +/- 1.10 kg were used. Dogs randomly received liposome encapsulated hydromorphone, 0.5 mg/kg IV (n = 6), 1.0 mg/kg (n = 6), 2.0 mg/kg (n = 6), or 3.0 mg/kg (n = 7) SC with a 14-28 day washout between trials. Blood was sampled at serial intervals after drug administration. Serum hydromorphone concentrations were measured using liquid chromatography with mass spectrometry. Serum concentrations of hydromorphone decreased rapidly after IV administration of the DPPC-C formulation (half-life = 0.52 h, volume of distribution = 12.47 L/kg, serum clearance = 128.97 mL/min/kg). The half-life of hydromorphone after SC administration of DPPC-C formulation at 1.0, 2.0, and 3.0 mg/kg was 5.22, 31.48, and 24.05 h, respectively. The maximum serum concentration normalized for dose (C(MAX)/D) ranged between 19.41-24.96 ng/mL occurring at 0.18-0.27 h. Serum hydromorphone concentrations fluctuated around 4.0 ng/mL from 6-72 h after 2.0 mg/kg and mean concentrations remained above 4 ng/mL for 96 h after 3.0 mg/kg DPPC-C hydromorphone. Liposome-encapsulated hydromorphone (DPPC-C) administered SC to healthy dogs provided a sustained duration of serum hydromorphone concentrations.


Asunto(s)
Analgésicos Opioides/administración & dosificación , Analgésicos Opioides/farmacocinética , Hidromorfona/administración & dosificación , Hidromorfona/farmacocinética , Analgésicos Opioides/sangre , Animales , Área Bajo la Curva , Química Farmacéutica , Perros , Semivida , Hidromorfona/sangre , Inyecciones Subcutáneas , Liposomas , Masculino , Tasa de Depuración Metabólica
20.
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