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1.
Nat Commun ; 10(1): 472, 2019 01 23.
Artículo en Inglés | MEDLINE | ID: mdl-30674884

RESUMEN

The original version of this Article contained an error in the author affiliations. Affiliation 5 incorrectly read 'Tyumen State Oil and Gas University, Tyumen, Tyument. Oblast, Russian Federation, 625000'.This has now been corrected in both the PDF and HTML versions of the Article.

2.
Nat Commun ; 9(1): 5423, 2018 12 21.
Artículo en Inglés | MEDLINE | ID: mdl-30575717

RESUMEN

Local observations indicate that climate change and shifting disturbance regimes are causing permafrost degradation. However, the occurrence and distribution of permafrost region disturbances (PRDs) remain poorly resolved across the Arctic and Subarctic. Here we quantify the abundance and distribution of three primary PRDs using time-series analysis of 30-m resolution Landsat imagery from 1999 to 2014. Our dataset spans four continental-scale transects in North America and Eurasia, covering ~10% of the permafrost region. Lake area loss (-1.45%) dominated the study domain with enhanced losses occurring at the boundary between discontinuous and continuous permafrost regions. Fires were the most extensive PRD across boreal regions (6.59%), but in tundra regions (0.63%) limited to Alaska. Retrogressive thaw slumps were abundant but highly localized (<10-5%). Our analysis synergizes the global-scale importance of PRDs. The findings highlight the need to include PRDs in next-generation land surface models to project the permafrost carbon feedback.

3.
Rev Sci Instrum ; 89(10): 10K122, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30399717

RESUMEN

This work illustrates predominant measureable nonlinearities in photomultiplier tubes (PMTs) and introduces a controllable one called "Superlinearity," signifying both a positive nonlinear response and the ability to extend linear operation by counteracting gain saturation mechanisms - charge depletion, space-charge field limitation, and secondary emission surface effects. Recognizing superlinearity and its effect on the temporal step response leads to a true definition of linearity, free of a small-signal linear assumption. Furthermore, given the prevalent use of glass microchannel-plate (MCP) PMTs in favor of a faster impulse response in spite of a small charge limit, we are motivated to examine their nonlinear amplitude response and deploy tailored gain bias string methods to fully harness the maximum linear gain as is usually done for transmissive metal mesh and reflective metal dynode PMTs. Our characterization methodology applies standard NIST-traceable calibrated laboratory equipment with absolute input-referenced techniques, examining step responses over many orders of magnitude in controlled illumination. By doing so, we quantitatively reveal the superlinearity strength independent of charge depletion, yielding true linear responsivity and effectively doubling the small-signal linear limit; this is very relevant to PMT modeling and charge deconvolution efforts. With further development, the tailoring strategies we introduce could be applied to MCP detectors, extracting all useful capillary charge with a significant improvement in large linear signal quality.

4.
Chem Commun (Camb) ; 52(4): 741-4, 2016 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-26564002

RESUMEN

Urea is considered a fundamental building block in prebiotic chemistry. Its formation on early Earth has not yet been explained satisfactorily and exogenous delivery has been considered. We report on the synthesis along with the first online and in situ identification of urea after exposing inorganic ices to ionizing radiation.


Asunto(s)
Hielo/análisis , Urea/síntesis química , Difusión , Medio Ambiente Extraterrestre , Meteoroides , Radiación , Análisis Espectral , Urea/química
5.
Clin Radiol ; 68(8): 780-4, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23623261

RESUMEN

AIM: To evaluate the clinical impact and cost-effectiveness of a multidisciplinary team (MDT) meeting in a large hospital in the UK. MATERIALS AND METHODS: A management plan for colorectal cancer patients was recorded by the supervising surgical consultant prior to the MDT meeting using the available clinical information and the available reports for imaging and histopathology. The recorded outcomes were then compared with the outcomes documented at the subsequent MDT meeting. The cost of the MDT meeting was calculated based on the salaries of individuals involved plus relevant overheads. A range of opportunity costs were considered, the most significant of which was the expenditure required to re-provide direct clinical care displaced by the MDT. RESULTS: Over a 3 month period a sample of 47 random cases were reviewed from the colorectal MDT. In three patients, there were significant differences between the preliminary consultant decision and the MDT recommendation: in one case management was changed based on further information about patient co-morbidity and performance status. In only one case was there a material alteration to a CT report, which altered management. The annual costs of running this colorectal local MDT alone were estimated at £162,734+ per annum with opportunity costs of at least twice that. CONCLUSION: The costs of MDT meetings are very high producing a small clinical impact. At a time of increasing financial and capacity pressure in healthcare systems, the use of scarce resources may be better deployed elsewhere.


Asunto(s)
Neoplasias Colorrectales/terapia , Comunicación Interdisciplinaria , Grupo de Atención al Paciente/organización & administración , Selección de Paciente , Anciano , Neoplasias Colorrectales/economía , Comorbilidad , Costos y Análisis de Costo , Femenino , Humanos , Masculino , Grupo de Atención al Paciente/economía , Estudios Prospectivos , Reino Unido
6.
J Plast Reconstr Aesthet Surg ; 64(9): 1132-7, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21570371

RESUMEN

BACKGROUND: Ecchymosis, oedema, haematoma and pain after SMAS-based facelift surgery are all the direct result of the physical trauma of surgery and subsequent inflammatory response. Hilotherapy is a novel form of cryotherapy that purports to minimise these events through single-use face masks circulating cooled, sterile water. This study was performed to assess the validity of Hilotherapy in this population of patients. METHODS: Over 14 weeks fifty consecutive patients were randomised to post-operative facial cooling with Hilotherapy or management with standard dressings alone, while fifteen subsequent, consecutive patients were randomised to cooling of one side of the face but not the other. Assessment of ecchymosis, oedema, haematoma and pain was performed independently by clinical staff and patients. The second analysis was undertaken to better delineate pain relief using each individual patient as their own control. RESULTS: The Hilotherapy mask produced a statistically significant difference in facial skin temperature (p = 0.01). In the second limb of the study patients reported a statistically significant increase in facial swelling 6-8 days post surgery in the half of the face that was treated with the mask (p = 0.05) but there was no significant difference in ecchymosis, haematoma and pain between comparison groups (p > 0.10) in either limb of the study. Subjectively the majority of patients found the cooling masks to be comforting. CONCLUSION: In this randomised, controlled trial the Hilotherapy mask produced significant facial skin cooling after SMAS-based facelift surgery at the expense of a statistically significant increase in patient reported post-operative swelling. No objective benefits were derived in terms of reducing ecchymosis, haematoma or pain.


Asunto(s)
Crioterapia/instrumentación , Máscaras , Cuidados Posoperatorios , Ritidoplastia , Anciano , Crioterapia/efectos adversos , Equimosis/prevención & control , Edema/etiología , Edema/prevención & control , Femenino , Hematoma/prevención & control , Humanos , Masculino , Persona de Mediana Edad , Dolor Postoperatorio/prevención & control , Estudios Prospectivos , Índice de Severidad de la Enfermedad , Temperatura Cutánea
7.
Behav Anal ; 34(1): 55-73, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-22532731

RESUMEN

The detection and subsequent removal of land mines and unexploded ordnance (UXO) from many developing countries are slow, expensive, and dangerous tasks, but have the potential to improve the well-being of millions of people. Consequently, those involved with humanitarian mine and UXO clearance are actively searching for new and more efficient detection technologies. Remote explosive scent tracing (REST) using trained dogs has the potential to be one such technology. However, details regarding how best to train, test, and deploy dogs in this role have never been made publicly available. This article describes how the key characteristics of applied behavior analysis, as described by Baer, Wolf and Risley (1968, 1987), served as important objectives for the research and development of the behavioral technology component of REST while the author worked in humanitarian demining.

8.
J Plast Reconstr Aesthet Surg ; 63(12): 2108-11, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20362523

RESUMEN

Macrolane™, an injectable compound composed of hyaluronic acid, has recently been marketed for breast enhancement. Three patients who presented to the authors with complications soon after treatment elsewhere are reported. One had severe infection and two had grade 3 capsular contracture. All three patients underwent a surgical procedure to treat their complication. The use of Macrolane™ for breast enhancement is reviewed together with previously published data.


Asunto(s)
Implantación de Mama/métodos , Implantes de Mama/efectos adversos , Ácido Hialurónico/administración & dosificación , Ácido Hialurónico/efectos adversos , Adulto , Femenino , Humanos , Ácido Hialurónico/uso terapéutico , Infección de Heridas/etiología
9.
J Plast Reconstr Aesthet Surg ; 61(7): 730-5, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18547885

RESUMEN

Bodylifting is often considered a high-risk surgical procedure. There is a widely held perception is that the operation is both time consuming and physically demanding for the surgeon, with, potentially, a long recovery and high complication rate for the patient. The senior author's experience of 16 consecutive bodylift procedures does not reflect this. Fourteen female patients and two male patients underwent Lockwood-type bodylifting procedures at two different hospitals over a 5 year period. Patients studied were unsuitable for a standard abdominoplasty either because of excess lateral abdominal tissue, or had undergone significant weight loss and developed redundant folds of skin in a circumferential pattern around the waistline. The average Body Mass Index (BMI) prior to surgery was 26.7. Mean surgical time and hospital stay was 4.2 hrs and 3.5 days respectively. No patient required blood transfusion. The follow up period was between 3 and 24 months. Levels of patient satisfaction were high and complications few. Only one patient required minor revisional surgery. No major complications were recorded. The commonest problem, seroma, developed in 4 out of 16 patients and was managed by simple aspiration. This study supports the effectiveness of the lower body lift as a procedure with the potential to produce an outcome unachievable by other means with a low incidence of minor complications.


Asunto(s)
Abdomen/cirugía , Procedimientos de Cirugía Plástica/métodos , Pérdida de Peso , Adulto , Cirugía Bariátrica , Índice de Masa Corporal , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Obesidad Mórbida/cirugía , Satisfacción del Paciente , Selección de Paciente , Procedimientos de Cirugía Plástica/efectos adversos , Estudios Retrospectivos , Resultado del Tratamiento
10.
J Plast Reconstr Aesthet Surg ; 59(11): 1152-5, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-17046623

RESUMEN

The case notes of 278 consecutive patients who underwent abdominoplasty, during a five-year period, in one institution under the care of four surgeons were reviewed. Patient details, early and late complications and revision procedures were noted. Seventy-five percent of patients had a 'full' abdominoplasty with undermining to costal cartilage and repositioning of the umbilicus and 23% had 'mini abdominoplasties', 2% were revision operations. Eighteen percent of patients suffered from early complications the most common of which were seroma (5%), haematoma (3%), infection (3%), skin or fat necrosis (2.5%) and delayed healing (2%). Twenty-five percent of patients had late complications which were often relatively minor. These included 'dog ears' (12%), localised fatty excess (10%) and unsatisfactory scars (8%). Twenty-four percent of patients underwent revision surgery. Most commonly further liposuction (12%), dog ear revision (10%) and scar revision (5%). Analysis failed to reveal significant risk factors. Despite an apparently high complication and revision rate the subjective impression is of a satisfied patient cohort.


Asunto(s)
Abdomen/cirugía , Procedimientos de Cirugía Plástica/efectos adversos , Adulto , Anciano , Cicatriz/etiología , Cicatriz/cirugía , Femenino , Hematoma/etiología , Humanos , Lipectomía/efectos adversos , Masculino , Persona de Mediana Edad , Procedimientos de Cirugía Plástica/métodos , Reoperación , Estudios Retrospectivos , Factores de Riesgo , Seroma/etiología , Cicatrización de Heridas
11.
J Plast Reconstr Aesthet Surg ; 59(11): 1177-87, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-17046627

RESUMEN

The chin is an important and often neglected feature of facial balance. Genioplasty is a useful procedure in aesthetic surgery and often can be combined with other procedures to obtain an optimal aesthetic outcome. A retrospective case note review of the senior author's (BMJ) experience of aesthetic genioplasty over an 11-year period was undertaken. Cases with non-aesthetic indications for genioplasty were excluded and overall 64 patients were included in this study. Our technique of intraoral osseous genioplasty is described and discussed. A total of 54 patients underwent osseous genioplasty, eight underwent alloplastic genioplasty and two underwent removal of a chin prosthesis only. Most of the patients who had an osseous genioplasty had a sliding advancement correction. Four of these patients required secondary surgery, five had additional minor complications and there were seven cases of transient numbness. Nine patients had a genioplasty alone, 26 had one additional procedure and 19 had more than one, with an average of 2.9 additional procedures. Twenty-four patients had a simultaneous rhinoplasty and 18 had a facelift. Osseous genioplasty is our preferred technique for its versatility and long-term stability compared to alloplastic methods. If performed correctly it provides excellent results with a high degree of patient satisfaction and few long-term complications.


Asunto(s)
Mentón/cirugía , Procedimientos de Cirugía Plástica/métodos , Adulto , Estética , Cara/anatomía & histología , Femenino , Humanos , Mandíbula/cirugía , Avance Mandibular/métodos , Persona de Mediana Edad , Osteotomía/métodos , Satisfacción del Paciente , Retrognatismo/cirugía , Estudios Retrospectivos , Rinoplastia , Ritidoplastia , Resultado del Tratamiento
12.
Scand J Rheumatol ; 34(5): 359-66, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-16234183

RESUMEN

OBJECTIVE: The incidence and clinical significance of anti-cyclic citrullinated peptide (CCP) antibodies in a cohort of Chinese patients with juvenile idiopathic arthritis (JIA) and adults with rheumatoid arthritis (RA) were studied. METHODS: Anti-CCP antibodies were determined by enzyme-linked immunosorbent assay (ELISA) in 59 patients with JIA, 129 adult RA patients, 48 children with diseases other than JIA, 68 adult patients with rheumatic diseases other than RA, and 60 normal adults. Associations between anti-CCP antibodies and clinical and laboratory parameters were determined by Fisher's exact test. RESULTS: Six of 59 (10.2%) patients with JIA and 71 of 129 (55%) patients with RA were positive for anti-CCP. Four of five RF-positive JIA patients and two of 54 RF-negative JIA patients were positive (p<0.001). One paediatric patient with allergy (0.9%) and two adult patients with rheumatic diseases other than RA (2.3%) were positive. All healthy controls were negative for anti-CCP. The specificity was 99.1% for JIA and 98.4% for RA. The sensitivity was 10.2% for JIA and 55% for RA. Positive predictive values were 85.7% for JIA and 97.3% for RA and negative predictive values were 66.9% for JIA and 68.5% for RA. CONCLUSION: The anti-CCP antibody assay is a valuable tool for the diagnosis of RA and a subset of JIA in Chinese patients. It could be a useful predictive test for joint erosion in JIA of the polyarticular RF-positive subset and may be influential in the choice of the best therapeutic strategy in patients with recent-onset arthritis.


Asunto(s)
Artritis Juvenil/diagnóstico , Artritis Juvenil/inmunología , Artritis Reumatoide/diagnóstico , Artritis Reumatoide/inmunología , Autoanticuerpos , Péptidos Cíclicos/inmunología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Artritis Juvenil/etnología , Artritis Reumatoide/etnología , Pueblo Asiatico , Autoanticuerpos/sangre , Biomarcadores , Niño , Preescolar , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Pronóstico , Estudios Seroepidemiológicos
14.
Clin Exp Immunol ; 135(3): 467-73, 2004 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15008980

RESUMEN

Severe acute respiratory syndrome (SARS) is a new disease which has spread rapidly and widely. We wished to know whether evaluation of in vitro cytokine production could contribute to improved understanding of disease pathogenesis and to better patient management. Numbers of unstimulated and mitogen-stimulated cytokine-secreting peripheral blood mononuclear cells were measured repeatedly during and after hospitalization in 13 patients with SARS using enzyme-linked immunospot technology. Numbers of interferon-gamma, interleukin (IL)-2, IL-4, IL-10 and IL-12 secreting cells induced by T cell activators were below normal in many or most patients before and during treatment with corticosteroids and ribavirin but returned essentially to normal after completion of treatment. Staphylococcus aureus Cowan 1 (SAC)-stimulated IL-10 secreting cells were increased in early SARS but fell during treatment. SAC-induced IL-12 secreting cells were deficient before, during and long after treatment. Numbers of cells induced to produce IL-6 and tumour necrosis factor-alpha by T cell or monocyte activators were higher than normal in many early SARS patients and were still increased in some during and after treatment. We conclude that prolonged dysregulated cytokine production occurs in SARS and that future studies should be directed at improving anti-inflammatory and antiviral therapies in order to limit cytokine impairment.


Asunto(s)
Corticoesteroides/uso terapéutico , Citocinas/biosíntesis , Ribavirina/uso terapéutico , Síndrome Respiratorio Agudo Grave/inmunología , Adulto , Antiinflamatorios/uso terapéutico , Antivirales/uso terapéutico , Células Cultivadas , Quimioterapia Combinada , Femenino , Humanos , Recuento de Leucocitos , Leucocitos/efectos de los fármacos , Leucocitos/inmunología , Activación de Linfocitos , Subgrupos Linfocitarios/efectos de los fármacos , Subgrupos Linfocitarios/inmunología , Masculino , Persona de Mediana Edad , Fitohemaglutininas/inmunología , Síndrome Respiratorio Agudo Grave/tratamiento farmacológico
15.
Anaesthesia ; 59(1): 44-51, 2004 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-14687098

RESUMEN

Facial bipartition is amongst the most radical craniofacial surgery undertaken but is performed rarely. There is little published information on its anaesthetic management. We undertook a retrospective case-note review of 22 consecutive patients undergoing bipartition surgery by the same surgical team in one centre in the period 1993-2001. There were incomplete data for two cases and these were therefore excluded. Patients were aged 2 months to 19 years. Conditions treated were facial cleft (n = 5), frontonasal dysplasia (n = 7) and facial dysostosis (n = 8).Intra-operative complications included major haemorrhage (n = 4), bradycardia (n = 3) and unintentional tracheal extubation (n = 1). There were no peri-operative deaths. All patients required intra-operative blood transfusion and 15% of them had a postoperative haemoglobin concentration > 115% of their pre-operative value. In this series, four patients required postoperative lung ventilation for a median duration of 3 days. Infants < 14 months old were significantly more likely to receive a massive blood transfusion (p = 0.0002), to have an excessively high postoperative haematocrit (p = 0.008) and to require postoperative lung ventilation (p = 0.0002) compared with older patients. We conclude that patients in this age group have a significantly increased risk of postoperative complications.


Asunto(s)
Anestesia General/métodos , Anomalías Craneofaciales/cirugía , Osteotomía/métodos , Adolescente , Adulto , Distribución por Edad , Factores de Edad , Transfusión Sanguínea , Niño , Preescolar , Anomalías Craneofaciales/diagnóstico por imagen , Fluidoterapia , Hemoglobinas/metabolismo , Humanos , Lactante , Complicaciones Intraoperatorias , Atención Perioperativa/métodos , Complicaciones Posoperatorias , Respiración Artificial , Estudios Retrospectivos , Tomografía Computarizada por Rayos X
16.
J Exp Anal Behav ; 79(3): 323-50, 2003 May.
Artículo en Inglés | MEDLINE | ID: mdl-12908761

RESUMEN

Six pigeons performed a simultaneous matching-to-sample (MTS) task involving patterns of dots on a liquid-crystal display. Two samples and two comparisons differed in terms of the density of pixels visible through pecking keys mounted in front of the display. Selections of Comparison 1 after Sample 1, and of Comparison 2 after Sample 2, produced intermittent access to food, and errors always produced a time-out. The disparity between the samples and between the comparisons varied across sets of conditions. The ratio of food deliveries for the two correct responses varied over a wide range within each set of conditions, and one condition arranged extinction for correct responses following Sample 1. The quantitative models proposed by Davison and Tustin (1978), Alsop (1991), and Davison (1991) failed to predict performance in some extreme reinforcer-ratio conditions because comparison choice approached indifference (and strong position biases emerged) when the sample clearly signaled a low (or zero) rate of reinforcement. An alternative conceptualization of the reinforcement contingencies operating in MTS tasks is advanced and was supported by further analyses of the data. This model relates the differential responding between the comparisons following each sample to the differential reinforcement for correct responses following that sample.


Asunto(s)
Discriminación en Psicología , Refuerzo en Psicología , Animales , Conducta Animal , Columbidae , Análisis por Apareamiento , Detección de Señal Psicológica
17.
Br J Plast Surg ; 55(6): 479-89, 2002 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-12479421

RESUMEN

This study set out to detect specific classes of potentially genotoxic aldehydes resulting from soybean-oil peroxidation in oil samples from 51 Trilucent implants in 26 patients and two factory-retained prostheses. The chemical analysis was performed independently of AEI inc. All of the implants showed evidence of shell deterioration suggestive of lipid absorption, and of lipid bleed throughout the implant shell. The mean implant weight loss was found to be almost 2% per year. Although none of the implants had actually ruptured in-situ, we identified specific problems with anterior and posterior patch delaminations, making the implant prone to rupture. Our data suggest that the soybean oil in all the explanted Trilucent implants and the two factory-retained prostheses had undergone peroxidation, yielding aldehyde by-products in millimolar concentrations. These concentrations are over 1000 times that thought to be potentially genotoxic. The clinical implications of these findings remain unclear. Capsular tissue was submitted to AEI Inc for histological and chemical analysis, but the data have not been forthcoming, which is disappointing as this may provide further evidence for the risks of long-term complications in these patients.


Asunto(s)
Implantes de Mama/efectos adversos , Aceite de Soja/química , Triglicéridos/química , Adulto , Anciano , Aldehídos/análisis , Diseño de Equipo , Femenino , Humanos , Peroxidación de Lípido , Persona de Mediana Edad , Falla de Prótesis , Elastómeros de Silicona/química , Viscosidad
18.
Br J Neurosurg ; 16(4): 348-54, 2002 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-12389887

RESUMEN

CT scanning is accepted as a regular component of the investigation of patients with simple craniosynostosis. In a series of 109 cases with simple craniosynostoses treated at Great Ormond Street Hospital for Children, a correct diagnosis on the basis of clinical findings was made in 100% of cases by an experienced clinician. CT scans with 3D reconstructions provided diagnostic confirmation in 100% of the patients when performed, but 91% of patients had already had sufficient confirmation of diagnosis by radiography. The clinical use of the scans for purposes other than diagnosis was examined. CT scanning in simple craniosynostosis in this series did not provide any additional clinical benefit as a screening method for the detection of intracranial abnormalities or for surgical planning. We propose that it may be appropriate to limit CT scanning, both axial images and three dimensional reconstructions, to selected cases where diagnostic uncertainty exists or where, it is used in surgical planning.


Asunto(s)
Craneosinostosis/diagnóstico por imagen , Cuidados Preoperatorios/métodos , Tomografía Computarizada por Rayos X/métodos , Preescolar , Craneosinostosis/cirugía , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Estudios Retrospectivos , Cráneo/diagnóstico por imagen
19.
Plast Reconstr Surg ; 108(7): 2026-39; discussion 2040-6, 2001 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11743396

RESUMEN

Mutations in the fibroblast growth factor receptor (FGFR) genes 1, 2, and 3 are causal in a number of craniofacial dysostosis syndromes featuring craniosynostosis with basicranial and midfacial deformity. Great clinical variability is displayed in the pathologic phenotypes encountered. To investigate the influence of developmental genetics on clinical diversity in these syndromes, the expression of several genes implicated in their pathology was studied at sequential stages of normal human embryo-fetal cranial base and facial ossification (n = 6). At 8 weeks of gestation, FGFR1, FGFR2, and FGFR3 are equally expressed throughout the predifferentiated mesenchyme of the cranium, the endochondral skull base, and midfacial mesenchyme. Both clinically significant isoforms of FGFR2, IgIIIa/c and IgIIIa/b, are coexpressed in maxillary and basicranial ossification. By 10 to 13 weeks, FGFR1 and FGFR2 are broadly expressed in epithelia, osteogenic, and chondrogenic cell lineages. FGFR3, however, is maximally expressed in dental epithelia and proliferating chondrocytes of the skull base, but poorly expressed in the osteogenic tissues of the midface. FGF2 and FGF4, but not FGF7, and TGFbeta1 and TGFbeta3 are expressed throughout both osteogenic and chondrogenic tissues in early human craniofacial skeletogenesis. Maximal FGFR expression in the skull base proposes a pivotal role for syndromic growth dysplasia at this site. Paucity of FGFR3 expression in human midfacial development correlates with the relatively benign human mutant FGFR3 midfacial phenotypes. The regulation of FGFR expression in human craniofacial skeletogenesis against background excess ligand and selected cofactors may therefore play a profound role in the pathologic craniofacial development of children bearing FGFR mutations.


Asunto(s)
Disostosis Craneofacial/genética , Factores de Crecimiento de Fibroblastos/genética , Expresión Génica , Genotipo , Fenotipo , Receptores de Factores de Crecimiento de Fibroblastos/genética , Cráneo/embriología , Factor de Crecimiento Transformador beta/genética , Disostosis Craneofacial/embriología , Craneosinostosis/genética , Esmalte Dental/química , Esmalte Dental/embriología , Huesos Faciales/química , Huesos Faciales/embriología , Edad Gestacional , Humanos , Inmunohistoquímica , Maxilar/química , Maxilar/embriología , Osteoblastos/química , Osteogénesis/genética , Osteonectina/genética , ARN Mensajero/análisis , Base del Cráneo/química , Base del Cráneo/embriología
20.
Artículo en Inglés | MEDLINE | ID: mdl-11696251

RESUMEN

BACKGROUND: Guolin Qigong is a combination of meditation, controlled breathing and physical movement designed to control the vital energy (qi) of the body and consequently to improve spiritual, physical and mental health. Practice of Qigong has been reported to alter immunological function, but there have been few studies of its effects on cytokines, the key regulators of immunity. METHODS: Numbers of peripheral blood cytokine-secreting cells were determined by ELISPOT in 19 healthy volunteers aged 27 - 55, before they were taught the practice of Qigong and after 3, 7 and 14 weeks of daily practice. The effect of Qigong on blood cortisol was also examined. RESULTS: Numbers of IL4 and IL12-secreting cells remained stable. IL6 increased at 7 weeks and TNFalpha increased in unstimulated cultures at 3 and 7 weeks but decreased at these times in LPS and SAC-stimulated cultures. Of particular interest, IFNgamma-secreting cells increased and IL10-secreting cells decreased in PHA-stimulated cultures, resulting in significant increases in the IFNgamma:IL10 ratio. Cortisol, a known inhibitor of type 1 cytokine production, was reduced by practicing Qigong. CONCLUSION: These preliminary studies in healthy subjects, although not necessarily representative of a randomized healthy population and not including a separate control group, have indicated that blood levels of the stress-related hormone cortisol may be lowered by short-term practice of Qigong and that there are concomitant changes in numbers of cytokine-secreting cells. Further studies of the effect of Qigong in patients with clinical diseases known to be associated with type 2 cytokine predominance are merited.


Asunto(s)
Ejercicios Respiratorios , Citocinas/biosíntesis , Adulto , Femenino , Humanos , Hidrocortisona/sangre , Interferón gamma/metabolismo , Interleucina-10/metabolismo , Interleucina-6/metabolismo , Masculino , Persona de Mediana Edad , Proyectos Piloto , Valores de Referencia , Factor de Necrosis Tumoral alfa/metabolismo
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