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1.
Ann Rheum Dis ; 76(1): 227-234, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27117700

RESUMEN

OBJECTIVES: To assess the safety of intra-articular (IA) autologous tolerogenic dendritic cells (tolDC) in patients with inflammatory arthritis and an inflamed knee; to assess the feasibility and acceptability of the approach and to assess potential effects on local and systemic disease activities. METHODS: An unblinded, randomised, controlled, dose escalation Phase I trial. TolDC were differentiated from CD14+ monocytes and loaded with autologous synovial fluid as a source of autoantigens. Cohorts of three participants received 1×106, 3×106 or 10×106 tolDC arthroscopically following saline irrigation of an inflamed (target) knee. Control participants received saline irrigation only. Primary outcome was flare of disease in the target knee within 5 days of treatment. Feasibility was assessed by successful tolDC manufacture and acceptability via patient questionnaire. Potential effects on disease activity were assessed by arthroscopic synovitis score, disease activity score (DAS)28 and Health Assessment Questionnaire (HAQ). Immunomodulatory effects were sought in peripheral blood. RESULTS: There were no target knee flares within 5 days of treatment. At day 14, arthroscopic synovitis was present in all participants except for one who received 10×106 tolDC; a further participant in this cohort declined day 14 arthroscopy because symptoms had remitted; both remained stable throughout 91 days of observation. There were no trends in DAS28 or HAQ score or consistent immunomodulatory effects in peripheral blood. 9 of 10 manufactured products met quality control release criteria; acceptability of the protocol by participants was high. CONCLUSION: IA tolDC therapy appears safe, feasible and acceptable. Knee symptoms stabilised in two patients who received 10×106 tolDC but no systemic clinical or immunomodulatory effects were detectable. TRIAL REGISTRATION NUMBER: NCT01352858.


Asunto(s)
Artritis Psoriásica/terapia , Artritis Reumatoide/terapia , Células Dendríticas/trasplante , Adulto , Anciano , Artritis Psoriásica/inmunología , Artritis Reumatoide/inmunología , Artroscopía/métodos , Células Dendríticas/inmunología , Estudios de Factibilidad , Femenino , Humanos , Tolerancia Inmunológica , Articulación de la Rodilla , Masculino , Persona de Mediana Edad , Aceptación de la Atención de Salud , Índice de Severidad de la Enfermedad , Trasplante Autólogo/efectos adversos , Trasplante Autólogo/métodos , Resultado del Tratamiento , Adulto Joven
2.
Ann Rheum Dis ; 73(6): 1027-36, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24618266

RESUMEN

OBJECTIVE: To compare the efficacy of etanercept (ETN) and methotrexate (MTX) versus MTX monotherapy for remission induction in patients with early inflammatory arthritis. METHODS: In a 78-week multicentre randomised placebo-controlled superiority trial, 110 DMARD-naïve patients with early clinical synovitis (≥1 tender and swollen joint, and within 3 months of diagnosis) and either rheumatoid factor, anticitrullinated protein antibodies or shared epitope positive were randomised 1:1 to receive MTX+ETN or MTX+placebo (PBO) for 52 weeks. Injections (ETN or PBO) were stopped in all patients at week 52. In those with no tender or swollen joints (NTSJ) for >26 weeks, injections were stopped early. If patients had NTSJ >12 weeks after stopping the injections, MTX was weaned. The primary endpoint was NTSJ at week 52. RESULTS: No statistically significant difference was seen for the primary endpoint (NTSJ at week 52 (32.5% vs 28.1% [adjusted OR 1.32 (0.56 to 3.09), p=0.522]) in the MTX+ETN and MTX+PBO groups, respectively). The secondary endpoints did not differ between groups at week 52 or 78. Exploratory analyses showed a higher proportions of patients with DAS28-CRP<2.6 in the MTX+ETN group at week 2 (38.5% vs 9.2%, adjusted OR 8.87 (2.53 to 31.17), p=0.001) and week 12 (65.1% vs 43.8%, adjusted OR 2.49 (1.12 to 5.54), p=0.026). CONCLUSIONS: In this group of patients with early inflammatory arthritis, almost a third had no tender, swollen joints after 1 year. MTX+ETN was not superior to MTX monotherapy in achieving this outcome. Clinical responses, however, including DAS28-CRP<2.6, were achieved earlier with MTX+ETN combination therapy. TRIAL REGISTRATION NUMBER: The EMPIRE trial is registered on the following trial registries: Eudract-2005-005467-29; ISRCTN 55428162 (http://www.controlled-trials.com/ISRCTN55428162/EMPIRE). The full trial protocol can be obtained from the corresponding author.


Asunto(s)
Antirreumáticos/uso terapéutico , Artritis/tratamiento farmacológico , Inmunoglobulina G/uso terapéutico , Metotrexato/uso terapéutico , Receptores del Factor de Necrosis Tumoral/uso terapéutico , Sinovitis/tratamiento farmacológico , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Artritis/inmunología , Artritis Reumatoide/tratamiento farmacológico , Artritis Reumatoide/inmunología , Autoanticuerpos/inmunología , Método Doble Ciego , Quimioterapia Combinada/métodos , Intervención Médica Temprana/métodos , Etanercept , Femenino , Humanos , Quimioterapia de Inducción/métodos , Masculino , Persona de Mediana Edad , Inducción de Remisión/métodos , Factor Reumatoide/inmunología , Resultado del Tratamiento , Adulto Joven
3.
Ann Rheum Dis ; 73(1): 75-85, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23912798

RESUMEN

OBJECTIVES: In disease modifying antirheumatic drug (DMARD)-naive early rheumatoid arthritis (RA), to compare the efficacy of methotrexate (MTX) and infliximab (IFX) with MTX and intravenous corticosteroid for remission induction. METHODS: In a 78-week multicentre randomised controlled trial, double-blinded to week 26, 112 treatment-naive RA patients (1987 American College of Rheumatology classification criteria) with disease activity score 44 (DAS44)>2.4 were randomised to MTX + IFX or MTX + single dose intravenous methylprednisolone 250 mg. A treat-to-target approach was used with treatment escalation if DAS44>2.4. In the IFX group, IFX was discontinued for sustained remission (DAS44<1.6 for 6 months). The primary outcome was change in modified total Sharp-van der Heijde score (mTSS) at week 50. RESULTS: The mean changes in mTSS score at week 50 in the IFX and intravenous steroid groups were 1.20 units and 2.81 units, respectively (adjusted difference (95% CI) -1.45 (-3.35 to 0.45); p=0.132). Radiographic non-progression (mTSS<2.0) occurred in 81% vs 71% (OR 1.77 (0.56 to 5.61); p=0.328). DAS44 remission was achieved at week 50 in 49% and 36% (OR 2.13 (0.91 to 5.00); p=0.082), and at week 78 in 48% and 50% (OR 1.12 (0.47 to 2.68); p=0.792). Exploratory analyses suggested higher DAS28 remission at week 6 and less ultrasound synovitis at week 50 in the IFX group. Of the IFX group, 25% (14/55) achieved sustained remission and stopped IFX. No substantive differences in adverse events were seen. CONCLUSIONS: In DMARD-naive early RA patients, initial therapy with MTX+high-dose intravenous steroid resulted in good disease control with little structural damage. MTX+IFX was not statistically superior to MTX+intravenous steroid when combined with a treat-to-target approach.


Asunto(s)
Anticuerpos Monoclonales/administración & dosificación , Antirreumáticos/administración & dosificación , Artritis Reumatoide/tratamiento farmacológico , Esteroides/administración & dosificación , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Anticuerpos Monoclonales/efectos adversos , Antirreumáticos/efectos adversos , Artritis Reumatoide/diagnóstico , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Femenino , Humanos , Infliximab , Inyecciones Intravenosas , Masculino , Persona de Mediana Edad , Inducción de Remisión , Resultado del Tratamiento , Adulto Joven
4.
Artículo en Inglés | MEDLINE | ID: mdl-38995603

RESUMEN

BACKGROUND: Atrial fibrillation and atrial flutter represent the most prevalent clinically significant cardiac arrhythmias. While the CHA2DS2-VASc score is commonly used to inform anticoagulation therapy decisions for patients with these conditions, its predictive power is limited. Therefore, we sought to improve risk prediction for left atrial appendage thrombus (LAAT), a known risk factor for stroke in these patients. METHODS: We developed and validated an explainable machine learning model using the eXtreme Gradient Boosting algorithm with 5 × 5 nested cross-validation. The primary outcome was to predict the probability of LAAT in patients with atrial fibrillation and atrial flutter who underwent transesophageal echocardiogram prior to cardioversion. Our algorithm used 37 demographic, comorbid, and transthoracic echocardiographic variables. RESULTS: A total of 795 patients were included in our analysis. LAAT was present in 11.3% of the patients. The average age of patients was 63.3 years and 34.7% were women. Patients with LAAT had significantly lower left ventricular ejection fraction (29.9% vs 43.5%; p < 0.001), lower E' lateral velocity (5.7 cm vs. 7.9 cm; p < 0.001) and higher E/A ratio (2.6 vs 1.8; p = 0.002). Our machine learning model achieved a high AUC of 0.79, with a high specificity of 0.82, and modest sensitivity of 0.57. Left ventricular ejection fraction was the most important variable in predicting LAAT. Patients were split into 10 buckets based on the percentile of their predicted probability of having thrombus. The lower the percentile (e.g., 10%), the lower the probability of having thrombus. Using a cutoff point of 0.16 which includes 10.0% of the patients, we can rule out thrombus with 100% confidence. CONCLUSION: Using machine learning, we refined the predictive power of predicting LAAT and explained the model. These results show promise in providing better guidance for anticoagulation therapy and cardioversion in AF and AFL patients.

5.
Clin Exp Rheumatol ; 30(3): 429-35, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22734971

RESUMEN

Despite its advantages in diagnosis, treatment and research, the role of arthroscopy in the management of rheumatic diseases has diminished due to the development of other less invasive means of joint assessment including advances in imaging techniques, e.g. ultrasound and magnetic resonance imaging. However, arthroscopy still provides invaluable information. By direct and precise internal inspection of a joint, arthroscopy allows the collection of synovial membrane samples (biopsies) of excellent quality, notably from the most representative pathological areas. Arthroscopy may also play a therapeutic role in the management of inflammatory arthritis (IA) by providing pain relief (lavage). Here we describe the procedure of knee arthroscopy under local anaesthesia, as well as an in situ visual assessment of synovial inflammation and its correlation with degree of histological and immunological abnormalities. With the emphasis being placed on early diagnosis and treatment initiation in patients with IA and as earlier initiation of targeted biologic therapies becomes more commonplace, the ability to predict which patients will respond to the different therapies available would be invaluable. Assessment of arthroscopic derived synovial biopsies has potential to play an important role in management of early IA in the future.


Asunto(s)
Artritis Reumatoide/patología , Artritis Reumatoide/terapia , Artroscopía/métodos , Articulación de la Rodilla/patología , Membrana Sinovial/patología , Artritis Reumatoide/inmunología , Biopsia/métodos , Humanos , Articulación de la Rodilla/inmunología , Membrana Sinovial/inmunología
6.
Ann Rheum Dis ; 69(2): 450-7, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19346219

RESUMEN

OBJECTIVE: Achieving joint regeneration in rheumatoid arthritis (RA) represents a future challenge. Autologous synovial mesenchymal stem cells (MSCs) could be therapeutically exploited. However, the inflammatory milieu in the RA synovium could adversely affect endogenous MSC function. To test this hypothesis, the frequency and multipotency of RA synovial MSCs was evaluated in relation to existing synovial inflammation. METHODS: Synovial inflammation was measured using the arthroscopic visual analogue score (VAS) and further validated using immunohistochemistry and flow cytometry. Highly proliferative clonogenic in vivo MSCs were enumerated following fluorescence-activated cell sorting and expansion for 20 population doublings. MSC multipotency was quantified following standard in vitro culture expansion and trilineage differentiation assays. Real-time PCR, flow cytometry and ELISA were used to evaluate pro- and anti-chondrogenic molecules in standard polyclonal synovial MSCs. RESULTS: The arthroscopic VAS significantly correlated with synovial macrophage infiltration. In RA, synovial MSC chondrogenesis was inhibited in direct relation to VAS (r = -0.777, p<0.05) and reduced compared with control osteoarthritis (OA)-MSCs (p<0.05). In vivo, MSCs resided in the synovial fibroblastic/stromal fraction (CD45(-)CD31(-)) and were reduced in frequency in relation to VAS (r = -0.695, p<0.05). In RA-MSCs, CD44 levels correlated negatively with inflammation and positively with chondrogenesis (r = -0.830 and r = 0.865, respectively). Cytokine production and Sox9 expression was similar in RA-MSCs and OA-MSCs. CONCLUSIONS: There is a negative relationship between synovial MSC chondrogenic and clonogenic capacities and the magnitude of synovitis in RA. Effective suppression of joint inflammation is therefore necessary for the development of autologous MSC treatments aimed at cartilage regeneration in RA.


Asunto(s)
Artritis Reumatoide/patología , Células Madre Mesenquimatosas/fisiología , Sinovitis/patología , Adulto , Anciano , Artroscopía , Recuento de Células , Diferenciación Celular , Células Cultivadas , Condrogénesis/fisiología , Citocinas/biosíntesis , Femenino , Humanos , Masculino , Células Madre Mesenquimatosas/metabolismo , Células Madre Mesenquimatosas/patología , Persona de Mediana Edad , Osteoartritis/patología , Fenotipo , Índice de Severidad de la Enfermedad
7.
Ann Rheum Dis ; 68(7): 1220-7, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18772191

RESUMEN

OBJECTIVES: Abatacept is the only agent currently approved to treat rheumatoid arthritis (RA) that targets the co-stimulatory signal required for full T-cell activation. No studies have been conducted on its effect on the synovium, the primary site of pathology. The aim of this study was to determine the synovial effect of abatacept in patients with RA and an inadequate response to tumour necrosis factor alpha (TNFalpha) blocking therapy. METHODS: This first mechanistic study incorporated both dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI) and arthroscopy-acquired synovial biopsies before and 16 weeks after therapy, providing tissue for immunohistochemistry and quantitative real-time PCR analyses. RESULTS: Sixteen patients (13 women) were studied; all had previously failed TNFalpha-blocking therapy. Fifteen patients completed the study. Synovial biopsies showed a small reduction in cellular content, which was significant only for B cells. The quantitative PCR showed a reduction in expression for most inflammatory genes (Wald statistic of p<0.01 indicating a significant treatment effect), with particular reduction in IFNgamma of -52% (95% CI -73 to -15, p<0.05); this correlated well with MRI improvements. In addition, favourable changes in the osteoprotegerin and receptor activator of nuclear factor kappa B levels were noted. DCE-MRI showed a reduction of 15-40% in MRI parameters. CONCLUSION: These results indicate that abatacept reduces the inflammatory status of the synovium without disrupting cellular homeostasis. The reductions in gene expression influence bone positively and suggest a basis for the recently demonstrated radiological improvements that have been seen with abatacept treatment in patients with RA.


Asunto(s)
Antirreumáticos/farmacología , Artritis Reumatoide/tratamiento farmacológico , Inmunoconjugados/farmacología , Factor de Necrosis Tumoral alfa/antagonistas & inhibidores , Abatacept , Artritis Reumatoide/patología , Femenino , Expresión Génica , Humanos , Inmunohistoquímica , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Proyectos Piloto , Estudios Prospectivos , ARN Mensajero/análisis , Resultado del Tratamiento , Factor de Necrosis Tumoral alfa/genética
8.
Science ; 261(5123): 909-11, 1993 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-8346441

RESUMEN

Related DNA binding proteins often recognize similar DNA sites but can distinguish among them with the use of different protein-DNA contacts. Here, it is shown that members of the C6 zinc cluster family of yeast transcriptional activators distinguish related DNA sites by a different mechanism. The DNA binding site for each of these proteins contains identical nucleotide triplets (CGG ... CCG) but differs in the spacings between the triplets. It is shown that zinc clusters of these proteins work interchangeably to recognize the conserved triplets and that the region 19 amino acids to the carboxyl-terminal side of the zinc cluster, comprising the linker and the beginning of a dimerization element as inferred from the GAL4 crystal structure, directs the protein to its preferred site.


Asunto(s)
Proteínas de Unión al ADN/química , Proteínas Fúngicas/química , Proteínas de Saccharomyces cerevisiae , Transactivadores/química , Factores de Transcripción/química , Secuencia de Aminoácidos , Secuencia de Bases , Sitios de Unión , ADN/metabolismo , Proteínas de Unión al ADN/metabolismo , Proteínas Fúngicas/metabolismo , Datos de Secuencia Molecular , Oligodesoxirribonucleótidos/metabolismo , Proteínas Recombinantes de Fusión/química , Proteínas Recombinantes de Fusión/metabolismo , Transactivadores/metabolismo , Factores de Transcripción/metabolismo
9.
Rheumatology (Oxford) ; 47(10): 1469-75, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18660510

RESUMEN

OBJECTIVES: Clinical response to TNF-alpha blockade in the treatment of RA is heterogeneous. The study aims were to determine whether pre-treatment synovial cytokine expression predicted infliximab response and whether synovial changes after therapy correlated with response. METHODS: Fifty-one patients had arthroscopic biopsies of the knee joint prior to infliximab (3 mg/kg) treatment. Synovial tissue cell numbers (CD68 and CD3 positive) and cytokine expression (TNF-alpha, lymphotoxin-alpha, IL-1alpha, -beta and receptor antagonist, and IL-6) pre-treatment was assessed using semi-quantitative immunohistochemistry. Changes in these parameters were assessed 16 weeks after infliximab in 32 patients who underwent repeat arthroscopic biopsy. RESULTS: Of the total patients, 47% (n = 24) achieved an ACR20 response; 53% (n = 27) did not. Baseline synovial TNF-alpha, IL-1alpha and -beta expression did not differ between the two groups. No differences in baseline TNF-alpha levels were observed with ACR levels of response (ACR20 and ACR50/70 groups). Post-treatment biopsies (17 ACR responders, 15 ACR non-responders) revealed significant reductions in sub-lining layer TNF-alpha expression in both response and non-response groups with significant reduction in vascularity and membrane proliferation scores. The worst ACR non-responders (<20% CRP suppression) demonstrated no reduction in any of the parameters. CONCLUSION: Pre-treatment synovial TNF-alpha or IL-1 expression does not predict TNF blockade response. Both ACR response and non-response was associated with reduction in synovial TNF-alpha-level expression. Suppression in TNF-alpha levels was not observed in the worst non-responders. The improvements (including in vascularity), independent of ACR clinical response, are compatible with the reduced structural damage documented in all groups of patients independent of response.


Asunto(s)
Anticuerpos Monoclonales/uso terapéutico , Antirreumáticos/uso terapéutico , Artritis Reumatoide/tratamiento farmacológico , Citocinas/metabolismo , Membrana Sinovial/metabolismo , Artritis Reumatoide/metabolismo , Artritis Reumatoide/patología , Artroscopía , Biomarcadores/metabolismo , Biopsia , Femenino , Estudios de Seguimiento , Humanos , Infliximab , Masculino , Persona de Mediana Edad , Pronóstico , Índice de Severidad de la Enfermedad , Membrana Sinovial/patología , Resultado del Tratamiento , Factor de Necrosis Tumoral alfa/antagonistas & inhibidores , Factor de Necrosis Tumoral alfa/metabolismo
10.
Aust Vet J ; 86(9): 354-6, 2008 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-18782418

RESUMEN

There have been anecdotal reports since 1962 of 'staggers' in sheep grazing Romulea rosea infested pastures, but this is the first detailed account. In September 2005, a locomotor disorder developed in 12 of 120 Merino wethers that had grazed R. rosea infested pasture at Albury, New South Wales, over several months. Affected sheep displayed signs that included limb paresis, knuckling over in the fetlocks, fine head tremor, incoordination, and an equilibrium disturbance characterised by frequent falling. The microscopic examination of brain and spinal cord tissues from two affected sheep revealed mild vacuolation, occasional lymphocytic cuffing around blood vessels, mild Wallerian degeneration, and occasional glial cells that contained honey-brown cytoplasmic pigments. The most significant changes were found in the cerebellum, where there were decreased numbers of Purkinje cells, increased numbers of glial cells, scattered vacuoles and occasional swollen axons. Previous reports of cerebellar toxicoses in ruminants have involved goats and cattle and have been associated with the ingestion of six Solanum spp. The Purkinje cell loss in this type of disorder is ultimately extensive and consequently affected animals may survive, but will remain permanently disabled.


Asunto(s)
Ataxia Cerebelosa/veterinaria , Ataxia de la Marcha/veterinaria , Intoxicación por Plantas/veterinaria , Enfermedades de las Ovejas/diagnóstico , Alimentación Animal/envenenamiento , Animales , Australia/epidemiología , Ataxia Cerebelosa/diagnóstico , Ataxia Cerebelosa/etiología , Ataxia Cerebelosa/patología , Resultado Fatal , Ataxia de la Marcha/diagnóstico , Ataxia de la Marcha/etiología , Ataxia de la Marcha/patología , Inmunohistoquímica/veterinaria , Masculino , Intoxicación por Plantas/complicaciones , Intoxicación por Plantas/diagnóstico , Intoxicación por Plantas/patología , Ovinos , Enfermedades de las Ovejas/patología , Síndrome
11.
Mol Cell Biol ; 19(1): 882-8, 1999 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9858611

RESUMEN

Saccharomyces cerevisiae responds to pyrimidine starvation by increasing the expression of four URA genes, encoding the enzymes of de novo pyrimidine biosynthesis, three- to eightfold. The increase in gene expression is dependent on a transcriptional activator protein, Ppr1p. Here, we investigate the mechanism by which the transcriptional activity of Ppr1p responds to the level of pyrimidine biosynthetic intermediates. We find that purified Ppr1p is unable to promote activation of transcription in an in vitro system. Transcriptional activation by Ppr1p can be observed, however, if either dihydroorotic acid (DHO) or orotic acid (OA) is included in the transcription reactions. The transcriptional activation function and the DHO/OA-responsive element of Ppr1p localize to the carboxyl-terminal 134 amino acids of the protein. Thus, Ppr1p directly senses the level of early pyrimidine biosynthetic intermediates within the cell and activates the expression of genes encoding proteins required later in the pathway. These results are discussed in terms of (i) regulation of the pyrimidine biosynthetic pathway and (ii) a novel mechanism of regulating gene expression.


Asunto(s)
Proteínas de Unión al ADN/metabolismo , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Pirimidinas/biosíntesis , Proteínas de Saccharomyces cerevisiae , Factores de Transcripción/metabolismo , Activación Transcripcional , Animales , Sitios de Unión , Línea Celular , ADN/metabolismo , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/aislamiento & purificación , Proteínas Fúngicas/aislamiento & purificación , Ácido Orótico/análogos & derivados , Ácido Orótico/farmacología , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/aislamiento & purificación , Proteínas Recombinantes de Fusión/metabolismo , Saccharomyces cerevisiae/genética , Factores de Transcripción/genética , Factores de Transcripción/aislamiento & purificación
12.
Poult Sci ; 86(1): 50-8, 2007 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17179415

RESUMEN

The comparative and sequential histopathology of different tissues of unvaccinated laying hens and cockerels were studied in chickens exposed to T and N1/88 strain of infectious bronchitis virus (IBV). The Harderian gland and trachea of hens and cockerels in both T- and N1/88-infected groups were damaged to a similar extent. The cecum was unaffected for both strains of IBV in both hens and cockerels. The sequential histopathological changes in hens revealed that IBV multiplies initially in the Harderian gland, then in the tracheal mucosa and simultaneously in the kidney and regions of the oviduct such as the magnum, tubular shell gland, and shell gland pouch. In cockerels, IBV multiplies first in the Harderian gland, then simultaneously in the trachea and kidney. Overall, the severity and persistence of lesions were greater in the kidneys of T-infected hens as compared with N1/88-infected hens. However, pathological changes in the kidney were mild in T- and N1/88-infected cockerels.


Asunto(s)
Pollos/virología , Infecciones por Coronavirus/veterinaria , Virus de la Bronquitis Infecciosa/clasificación , Virus de la Bronquitis Infecciosa/patogenicidad , Enfermedades de las Aves de Corral/patología , Enfermedades de las Aves de Corral/virología , Animales , Infecciones por Coronavirus/patología , Infecciones por Coronavirus/virología , Femenino , Tracto Gastrointestinal/patología , Tracto Gastrointestinal/virología , Glándula de Harder/patología , Glándula de Harder/virología , Riñón/virología , Masculino , Oviductos/patología , Oviductos/virología , Tráquea/virología
13.
Poult Sci ; 86(1): 59-62, 2007 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17179416

RESUMEN

The comparative histopathology of 2 different strains of infectious bronchitis virus (T and N1/ 88) in vaccinated hens was studied at 110 wk of age. The Harderian gland showed similar histopathology in T- and N1/88-infected hens. The trachea and kidney of challenged vaccinated hens were protected to a moderate extent, but the oviduct was protected to only a small extent. The severity and persistence of lesions were greater in tubular shell gland, shell gland pouch, and kidney of the T-infected hens, whereas, for the magnum, N1/88 had a greater effect.


Asunto(s)
Pollos/virología , Infecciones por Coronavirus/veterinaria , Virus de la Bronquitis Infecciosa/clasificación , Virus de la Bronquitis Infecciosa/inmunología , Enfermedades de las Aves de Corral/inmunología , Enfermedades de las Aves de Corral/virología , Vacunas Virales/administración & dosificación , Vacunas Virales/inmunología , Animales , Pollos/crecimiento & desarrollo , Pollos/inmunología , Infecciones por Coronavirus/inmunología , Infecciones por Coronavirus/prevención & control , Infecciones por Coronavirus/virología , Femenino , Glándula de Harder/patología , Glándula de Harder/virología , Riñón/patología , Riñón/virología , Oviductos/patología , Oviductos/virología , Enfermedades de las Aves de Corral/prevención & control , Serotipificación , Tráquea/patología , Tráquea/virología
14.
J Mol Biol ; 215(4): 493-5, 1990 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-2172550

RESUMEN

The 64 x 10(3) Mr N-terminal breakage-reunion domain of the Escherichia coli DNA gyrase A protein was purified from an over-expressing strain. When complexed with the gyrase B protein, this truncated A protein has all of the enzymic properties of the full-length counterpart, although with reduced efficiency in some cases. The 64 x 10(3) Mr protein has been crystallized in several forms, a number of which were too small for crystallographic analysis. However, two forms grew to sufficient size for preliminary X-ray analysis. Both forms were tetragonal with a primitive lattice. One form (type I) had cell dimensions of a = b = 170 A, c = 145 A a space group of either P41212 (P43212) or P42212, and diffracted to 6 A resolution. The type II crystals had cell dimensions of a = b = 177 A, c = 175 A, a space group of P41212 (P43212) or P42212, and diffracted to at least 4.5 A resolution. Both crystal forms apparently contained four subunits (possibly a tetramer) in the asymmetric unit. We are attempting to increase the size and quality of these crystals.


Asunto(s)
ADN-Topoisomerasas de Tipo II/química , Escherichia coli/enzimología , ADN-Topoisomerasas de Tipo II/metabolismo , ADN Bacteriano/metabolismo , Peso Molecular , Desnaturalización Proteica , Difracción de Rayos X
15.
Genetics ; 142(4): 1069-82, 1996 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-8846888

RESUMEN

Proline can serve as a nitrogen source for the yeast Saccharomyces cerevisiae when preferred sources of nitrogen are absent from the growth medium. PUT3, the activator of the proline utilization pathway, is required for the transcription of the genes encoding the enzymes that convert proline to glutamate. PUT3 is a 979 amino acid protein that constitutively binds a short DNA sequence to the promoters of its target genes, but does not activate their expression in the absence of induction by proline and in the presence of preferred sources of nitrogen. To understand how PUT3 is converted from an inactive to an active state, a dissection of its functional domains has been undertaken. Biochemical and molecular tests, domain swapping experiments, and an analysis of activator-constitutive and activator-defective mutant proteins indicate that PUT3 is dimeric and activates transcription with its negatively charged carboxyterminus, which does not appear to contain a proline-responsive domain. A mutation in the conserved central domain found in many fungal activators interferes with activation without affecting DNA binding protein stability. Intragenic suppressors of the central domain mutation have been isolated and analyzed.


Asunto(s)
Proteínas Fúngicas/genética , Prolina/metabolismo , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae/genética , Transactivadores/genética , Secuencia de Bases , Sitios de Unión , ADN de Hongos , Proteínas Fúngicas/química , Datos de Secuencia Molecular , Mutación , Nitrógeno/metabolismo , Soluciones , Transactivadores/química , Factores de Transcripción
16.
J Invest Dermatol ; 87(6): 683-7, 1986 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-3782854

RESUMEN

To determine whether the morphology of dermatophytes plays a role in the clinical manifestation of dermatophytosis, we isolated spores and mycelia from colonies of killed Trichophyton mentagrophytes and tested their ability to induce gross and microscopic cutaneous changes when applied to guinea pig skin. The skin of normal guinea pigs failed to develop any cutaneous changes after inoculation with either dead spores or mycelia. In contrast, guinea pigs that had recovered from a T. mentagrophytes infection reacted to topically applied spores by producing pustules but failed to develop pustules either grossly or microscopically when inoculated with mycelia. Because differences in the activation of C' and the subsequent generation of the polymorphonuclear leukocyte (PMN) chemoattractant, C5a, might account for our in vivo findings, we measured the amount of C5a activated in vitro when serum was incubated with equivalent amounts of spores or mycelia. Spores consistently activated more C' to C5a than mycelia, although each could activate serum C'. The results support previous studies that show a direct correlation between the clinical manifestations of a dermatophytic infection and the development of immunity against the dermatophyte. Furthermore, the data suggest that a dermatophyte's predominant morphology during an infection may play a critical role in producing pustules by activating C' and chemoattracting PMNs into the fungus-laden stratum corneum.


Asunto(s)
Activación de Complemento , Dermatomicosis/etiología , Trichophyton/fisiología , Animales , Complemento C5/biosíntesis , Complemento C5a , Dermatomicosis/patología , Cobayas , Esporas Fúngicas
17.
Endocrinology ; 96(3): 732-8, 1975 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-803898

RESUMEN

The effect of crude extract of porcine stalk-medium eminence (SME) on release of prolactin, measured by radioimmunoassay, has been studied in the rat. In male rats, intravenous administration of 3-4 SME equivalents caused an acute increase in serum prolactin levels. This prolactin-releasing factor (PRF) effect was observed in rats anesthetized with either pentobarbital or ether, and was not dependent upon estrogen pretreatment of the animals. Prolactin release was not seen with doses of 5 or 50 mug of synthetic thyrotropin-releasing hormone (TRH). The presence of porcine SME extract enhanced the release of prolactin by male rat pituitary halves incubated for 2 h in Medium 199. This effect was observed whether or not pituitary donors were pretreated with estrogen. In contrast to the observations in male animals, administration of 3 porcine SME equivalents to lactating rats separated from their litters for 4 h did not elevate serum prolactin. Failure to observe PRF activity could not be accounted for by the anesthetic employed. In vitro, porcine SME extract did not stimulate release of prolactin by pituitaries from lactating rats. Intraperitoneal injection of extract of 3 porcine SME equivalents inhibited the increase in serum prolactin which occurs when lactating rats are reunited with their litters for 30 min after 4 h of separation. These results are consistent with the concept that suckling-induced prolactin release is accomplished by cessation of discharge of a prolactin release-inhibiting factor (PIF). Furthermore, since effects of PRF were observed only in male rats, it is also concluded that the physiological state of animals treated with hypothalamic extracts is an important factor in determining responsiveness to either PIF or PRF.


Asunto(s)
Hipotálamo/fisiología , Prolactina/metabolismo , Animales , Corteza Cerebral/fisiología , Estrógenos/farmacología , Éter/farmacología , Femenino , Técnicas In Vitro , Lactancia , Masculino , Privación Materna , Eminencia Media/fisiología , Pentobarbital/farmacología , Embarazo , Prolactina/sangre , Radioinmunoensayo , Ratas , Factores Sexuales , Hormona Liberadora de Tirotropina/farmacología , Extractos de Tejidos/farmacología
18.
Gene ; 126(1): 105-7, 1993 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-8472950

RESUMEN

A DNA fragment encoding the yeast GAL4 transcriptional activator DNA-binding domain (amino acids 1-93) was cloned into an Escherichia coli expression vector such that the overproduced protein is tagged with six histidine residues and a factor Xa protease cleavage site. The vector also contains unique restriction sites at the 3' end of the gene to allow the construction of fusion proteins. These fusion proteins can easily be purified to homogeneity and their activity tested in vitro.


Asunto(s)
Proteínas Fúngicas/genética , Proteínas de Saccharomyces cerevisiae , Factores de Transcripción , Secuencia de Aminoácidos , Secuencia de Bases , Clonación Molecular , ADN Recombinante , Proteínas de Unión al ADN , Escherichia coli , Proteínas Fúngicas/aislamiento & purificación , Vectores Genéticos , Datos de Secuencia Molecular , Fragmentos de Péptidos/genética , Fragmentos de Péptidos/aislamiento & purificación , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/aislamiento & purificación , Mapeo Restrictivo , Solubilidad
19.
Pediatrics ; 65(2): 221-5, 1980 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-7354966

RESUMEN

Support provided to families experiencing the loss of an infant to sudden infant death syndrome has focused on the description of maternal bonding and the consequences to the mother. However fathers also develop significant relationships with their infants, and their responses to the unanticipated loss of their children may be different than those of mothers. In this study 28 fathers who lost infants to SIDS appeared to have identifiable patterns of behavior which were more peculiar to men: (1) the necessity to "keep busy" with increased work; (2) feelings of diminished self-worth; (3) self-blame because of lack of "care" involvement; and (4) a limited ability to ask for help. That men should be stoic and less emotional and that one need not be concerned with the reactions of fathers appears to be a reflection of societal attitudes. However, these paternal behaviors, which emerge at a time of crisis and which obstruct full expression of grief, may unwittingly be promoted by medical and health care providers who are anxious to help fathers fulfill societal expectations of masculine strength.


Asunto(s)
Conducta , Padre/psicología , Pesar , Muerte Súbita del Lactante , Adolescente , Adulto , Intervención en la Crisis (Psiquiatría) , Relaciones Padre-Hijo , Femenino , Identidad de Género , Humanos , Lactante , Masculino
20.
Arch Pediatr Adolesc Med ; 154(1): 11-5, 2000 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-10632244

RESUMEN

OBJECTIVES: To determine the relative incidence of accidental and abusive causes of head injuries in children younger than 6.5 years, to identify the types of craniocerebral damage resulting from reported mechanisms of injury, and to assess the likelihood of injuries being accidental or inflicted. METHODS: Retrospective review of medical records of 287 children with head injuries aged 1 week to 6.5 years admitted to a metropolitan children's hospital from January 1986 through December 1991. Those patients with diagnoses of skull fracture; concussion; subarachnoid hemorrhage (SAH); subgaleal, epidural, or subdural hematoma (SDH); parenchymal contusion or laceration; and closed head injury were included. Criteria were used for inclusion in categories of definite abuse or accident. RESULTS: Accidents accounted for 81% of cases and definite abuse for 19%. The mean age of the accident group was 2.5 years and for the definite abuse group, 0.7 years. Major differences were seen in the incidence of the following: SDH, 10% in the the accident group and 46% in the the definite abuse group; SAH, 8% in accident group and 31% in the definite abuse abuse; and retinal hemorrhages, 2% in the accident group and 33% in the definite abuse group. Associated cutaneous injuries consistent with inflicted injury were seen in 16% of the accident group and 50% of the definite abuse group. Twenty-three percent of those in the accident group were injured in motor vehicle crashes (MVCs), 58% by falls, 2% in play activities, and the rest had insufficient medical record information. In 56% of those in the definite abuse group, there was no history to account for the injuries and no history of MVC. In 17%, a fall was said to have been the mechanism of injury. In 24%, inflicted injury was admitted. Mortality rates were 13% in the definite abuse group and 2% in the accident group. Median hospital stay was 9.5 days for the definite abuse group and 3 days for the accident group. In falls less than 4 feet in the accident group, 8% had SDH, 2% had SAH, and none had retinal hemorrhages; among those in the definite abuse group reportedly falling less than 4 feet, 38% had SDH, 38% had SAH, and 25% had retinal hemorrhages. CONCLUSIONS: A substantial percentage of head injuries requiring hospitalization in children younger than 6.5 years are attributable to inflicted injury. Subdural hematoma, subarachnoid hemorrhage, retinal hemorrhages, and associated cutaneous, skeletal, and visceral injuries are significantly more common in inflicted head injury than in accidental injury.


Asunto(s)
Maltrato a los Niños/diagnóstico , Traumatismos Craneocerebrales/etiología , Accidentes por Caídas , Accidentes de Tránsito , Lesiones Encefálicas/epidemiología , Lesiones Encefálicas/etiología , Niño , Maltrato a los Niños/estadística & datos numéricos , Preescolar , Traumatismos Craneocerebrales/epidemiología , Femenino , Hospitalización/estadística & datos numéricos , Humanos , Incidencia , Lactante , Tiempo de Internación/estadística & datos numéricos , Masculino , Estudios Retrospectivos , Fracturas Craneales/epidemiología , Fracturas Craneales/etiología , Tasa de Supervivencia
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