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1.
BMC Oral Health ; 24(1): 87, 2024 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-38229079

RESUMO

BACKGROUND: Numerous studies have demonstrated a high likelihood of malocclusions resulting from non-nutritive sucking. Consequently, quantifying the impact of pacifiers can potentially aid in preventing the development or exacerbation of malocclusions and guide the design of improved performance pacifiers. METHODS: This work proposes and assesses a computational methodology that can effectively gather crucial information and provide more precise data regarding the consequences of non-nutritive pacifier sucking. The computational framework utilized is based on solids4Foam [1, 2], a collection of numerical solvers developed within the OpenFOAM® computational library [3]. The computational model focuses on the palate of a six-month-old baby and incorporates various components such as palate tissues, pacifier and tongue, and considers the negative intraoral pressure generated and the tongue displacement. Different models were tested, each offering varying levels of detail in representing the palate structure. These models range from a simplified approach, with one tissue, to a more intricate representation, involving up to five different tissues, offering a more comprehensive palate model compared to existing literature. RESULTS: The analysis of results involved examining the distribution of stress on the palate surface, as well as the displacement and forces exerted on the dental crowns. By comparing the obtained results, it was possible to evaluate the precision of the approaches previously described in the literature. The findings revealed that the predictions were less accurate when using the simplified model with a single tissue for the palate, which is the most common approach proposed in the literature. In contrast, the results demonstrated that the palate model with the most intricate structure, incorporating five different tissues, yielded distinct outcomes compared to all other combinations. CONCLUSIONS: The computational methodology proposed, employing the most detailed palate model, has demonstrated its effectiveness and necessity in obtaining accurate data on the impact of non-nutritive sucking habits, which are recognized as a primary contributor to the development of dental malocclusions. In the future, this approach could be extended to conduct similar studies encompassing diverse pacifier designs, sizes, and age groups. This would foster the design of innovative pacifiers that mitigate the adverse effects of non-nutritive sucking on orofacial structures.


Assuntos
Má Oclusão , Lactente , Humanos , Feminino , Má Oclusão/etiologia , Chupetas/efeitos adversos , Comportamento de Sucção , Hábitos , Língua , Aleitamento Materno
2.
Aust Vet J ; 101(8): 308-312, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37291800

RESUMO

A 4-month old, 200 kg, grey warmblood colt presented for a firm, non painful mass on the distal medial aspect of the left third metatarsus. Excisional biopsy revealed a diagnosis of haemangiosarcoma. Equine haemangiosarcoma is uncommon and only limited reports of successful treatment are available. The prognosis for survival is therefore considered to be poor. After two separate incidences of recurrence with incomplete excision of the tumour, intralesional treatment with cisplatin without excision or debulking was performed on three separate occasions. Intralesional cisplatin injection was performed at monthly intervals for three treatments. Four years post treatment with cisplatin, the horse remained in remission. This case report describes the diagnostic and treatment challenges for successful treatment of a primary haemangiosarcoma on the distal limb of a warmblood foal using intralesional cisplatin chemotherapy.


Assuntos
Hemangiossarcoma , Doenças dos Cavalos , Animais , Masculino , Cavalos , Cisplatino/uso terapêutico , Hemangiossarcoma/tratamento farmacológico , Hemangiossarcoma/veterinária , Hemangiossarcoma/diagnóstico , Prognóstico , Doenças dos Cavalos/diagnóstico
3.
Philos Trans A Math Phys Eng Sci ; 379(2190): 20200175, 2021 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-33342378

RESUMO

Using data from the Helioseismic Magnetic Imager, we report on the amplitudes and phase relations of oscillations in quiet-Sun, plage, umbra and the polarity inversion line (PIL) of an active region NOAA#11158. We employ Fourier, wavelet and cross-correlation spectra analysis. Waves with 5 min periods are observed in umbra, PIL and plage with common phase values of ϕ(v, I) = π/2, ϕ(v, Blos) = -(π/2). In addition, ϕ(I, Blos) = π in plage are observed. These phase values are consistent with slow standing or fast standing surface sausage wave modes. The line width variations, and their phase relations with intensity and magnetic oscillations, show different values within the plage and PIL regions, which may offer a way to further differentiate wave mode mechanics. Significant Doppler velocity oscillations are present along the PIL, meaning that plasma motion is perpendicular to the magnetic field lines, a signature of Alvènic waves. A time-distance diagram along a section of the PIL shows Eastward propagating Doppler oscillations converting into magnetic oscillations; the propagation speeds range between 2 and 6 km s-1. Lastly, a 3 min wave is observed in select regions of the umbra in the magnetogram data. This article is part of the Theo Murphy meeting issue 'High-resolution wave dynamics in the lower solar atmosphere'.

4.
Anaesthesia ; 75(8): 1086-1095, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32311771

RESUMO

Healthcare workers are at risk of infection during the severe acute respiratory syndrome coronavirus-2 pandemic. International guidance suggests direct droplet transmission is likely and airborne transmission occurs only with aerosol-generating procedures. Recommendations determining infection control measures to ensure healthcare worker safety follow these presumptions. Three mechanisms have been described for the production of smaller sized respiratory particles ('aerosols') that, if inhaled, can deposit in the distal airways. These include: laryngeal activity such as talking and coughing; high velocity gas flow; and cyclical opening and closure of terminal airways. Sneezing and coughing are effective aerosol generators, but all forms of expiration produce particles across a range of sizes. The 5-µm diameter threshold used to differentiate droplet from airborne is an over-simplification of multiple complex, poorly understood biological and physical variables. The evidence defining aerosol-generating procedures comes largely from low-quality case and cohort studies where the exact mode of transmission is unknown as aerosol production was never quantified. We propose that transmission is associated with time in proximity to severe acute respiratory syndrome coronavirus-1 patients with respiratory symptoms, rather than the procedures per se. There is no proven relation between any aerosol-generating procedure with airborne viral content with the exception of bronchoscopy and suctioning. The mechanism for severe acute respiratory syndrome coronavirus-2 transmission is unknown but the evidence suggestive of airborne spread is growing. We speculate that infected patients who cough, have high work of breathing, increased closing capacity and altered respiratory tract lining fluid will be significant producers of pathogenic aerosols. We suggest several aerosol-generating procedures may in fact result in less pathogen aerosolisation than a dyspnoeic and coughing patient. Healthcare workers should appraise the current evidence regarding transmission and apply this to the local infection prevalence. Measures to mitigate airborne transmission should be employed at times of risk. However, the mechanisms and risk factors for transmission are largely unconfirmed. Whilst awaiting robust evidence, a precautionary approach should be considered to assure healthcare worker safety.


Assuntos
Betacoronavirus , Infecções por Coronavirus/transmissão , Pessoal de Saúde , Transmissão de Doença Infecciosa do Paciente para o Profissional , Pneumonia Viral/transmissão , Aerossóis , Microbiologia do Ar , COVID-19 , Reanimação Cardiopulmonar/efeitos adversos , Infecções por Coronavirus/fisiopatologia , Infecções por Coronavirus/prevenção & controle , Expiração/fisiologia , Humanos , Controle de Infecções/métodos , Transmissão de Doença Infecciosa do Paciente para o Profissional/prevenção & controle , Máscaras , Nebulizadores e Vaporizadores , Pandemias/prevenção & controle , Tamanho da Partícula , Pneumonia Viral/fisiopatologia , Pneumonia Viral/prevenção & controle , Fenômenos Fisiológicos Respiratórios , SARS-CoV-2
5.
Clin Exp Dermatol ; 43(6): 713-717, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29744913

RESUMO

Cartilage-hair hypoplasia (CHH) is an autosomal recessive chondrodysplasia characterized by short-stature, sparse hair and impaired cellular immunity. We describe a young girl who was diagnosed with CHH based on the findings of recurrent infections, short stature with metaphyseal chondrodysplasia, and a confirmed bi-allelic RMRP gene mutation. At 13 years, the patient developed an Epstein-Barr virus (EBV)-driven lymphoproliferative disorder involving the lung, which responded partially to chemotherapy. Simultaneously, she developed multiple indurated plaques involving her face, which had histological findings of granulomatous inflammation and EBV-associated low-grade lymphomatoid granulomatosis. The patient received a matched unrelated peripheral blood stem cell transplant at 15 years of age, and her immunological parameters and skin lesions improved. Lymphomatoid forms of granulomatosis and cutaneous EBV-associated malignancies have not been described previously in CHH. This case highlights the possibility of EBV-associated cutaneous malignancy in CHH.


Assuntos
Cabelo/anormalidades , Doença de Hirschsprung/complicações , Síndromes de Imunodeficiência/complicações , Neoplasias Pulmonares/complicações , Pulmão/patologia , Granulomatose Linfomatoide/complicações , Osteocondrodisplasias/congênito , Neoplasias Cutâneas/complicações , Adolescente , Feminino , Herpesvirus Humano 4/isolamento & purificação , Doença de Hirschsprung/terapia , Humanos , Síndromes de Imunodeficiência/terapia , Pulmão/virologia , Neoplasias Pulmonares/patologia , Granulomatose Linfomatoide/patologia , Osteocondrodisplasias/complicações , Osteocondrodisplasias/terapia , Doenças da Imunodeficiência Primária , Transplante de Células-Tronco
6.
Anaesthesia ; 73(1): 130-132, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29210041
7.
J Econ Entomol ; 109(4): 1683-90, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27122493

RESUMO

Methyl anthranilate was identified as the active compound in extracts of maize (Zea mays L.) roots that were shown to be repellent to neonate western corn rootworm (Diabrotica virgifera virgifera LeConte) larvae. A bioassay-driven approach was used to isolate the active material from diethyl ether extracts of roots from germinating maize seeds. Separation of the extract on a Florisil column yielded an active fraction of 90:10 hexane:diethyl ether. Analysis with gas chromatography-mass spectrometry identified two compounds in the active fraction: indole (2,3-benzopyrrole) and methyl anthranilate (methyl 2-aminobenzoate). When tested in behavioral bioassays, methyl anthranilate elicited a significant (P < 0.05) repellent response at doses of 1, 10, and 100 µg. In subsequent single-choice bioassays, 1, 10, and 100 µg of methyl anthranilate prevented larvae from approaching 10 mmol/mol concentrations of carbon dioxide, which is normally highly attractive to the larvae. Indole, the other compound identified from the active fraction, did not elicit a behavioral response by the larvae. Methyl anthranilate has potential for development as a management tool for western corn rootworm larvae and may be best suited for use in a push-pull control strategy.


Assuntos
Besouros , Repelentes de Insetos , ortoaminobenzoatos , Animais , Dióxido de Carbono/metabolismo , Relação Dose-Resposta a Droga , Cromatografia Gasosa-Espectrometria de Massas , Larva/crescimento & desenvolvimento , Extratos Vegetais/química , Raízes de Plantas/química , Zea mays/crescimento & desenvolvimento
8.
Arch Dis Child Fetal Neonatal Ed ; 101(1): F67-71, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25956670

RESUMO

OBJECTIVE: To systematically review current evidence regarding prenatal diagnosis and management of transient abnormal myelopoiesis (TAM) in fetuses with trisomy 21. A novel case of GATA1-positive TAM, in which following serial in utero blood transfusion clinical improvement and postnatal remission were observed, is included. SEARCH STRATEGY AND DATA COLLECTION: A systematic search of electronic databases (inception to October 2014) and reference lists, hand-searching of journals and expert contact. All confirmed cases of prenatal TAM were included for analysis. Data on study characteristics, design and quality were obtained. RESULTS: Of 73 potentially relevant citations identified, 22 studies were included, describing 39 fetuses. All studies included comprised single case or small cohort studies; overall quality was 'very low'. Fetal/neonatal outcome was poor; 12 stillbirths (30.8%), 4 neonatal deaths (10.2%) and 7 infant deaths (17.9%). In two cases, the pregnancy was terminated (5.1%). TAM was primarily detected in the third trimester (79.4%), and in 14 a retrospective diagnosis was made postpartum. Ultrasound features indicative of TAM included hepatomegaly±splenomegaly (79.5%), hydrops fetalis (30.8%), pericardial effusion (23.1%) and aberrant liquor volume (15.4%). When performed, liver function tests were abnormal in 91.6% of cases. CONCLUSIONS: Prenatal TAM presents a challenging diagnosis, and prognosis is poor, with consistently high mortality. A low threshold to measure haematological and biochemical markers is advised when clinical features typical of TAM are detected in the context of trisomy 21. Larger prospective studies are warranted to accurately ascertain the role of GATA1 analysis and potential value of prenatal therapy.


Assuntos
Síndrome de Down/diagnóstico , Reação Leucemoide/diagnóstico , Diagnóstico Pré-Natal/métodos , Adulto , Síndrome de Down/genética , Síndrome de Down/terapia , Feminino , Feto , Fator de Transcrição GATA1/genética , Humanos , Recém-Nascido , Reação Leucemoide/genética , Reação Leucemoide/terapia , Gravidez , Prognóstico
9.
Sol Phys ; 290(5): 1507-1529, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26069350

RESUMO

Time-dependent three-dimensional magnetohydrodynamics (MHD) simulation modules are implemented at the Joint Science Operation Center (JSOC) of the Solar Dynamics Observatory (SDO). The modules regularly produce three-dimensional data of the time-relaxed minimum-energy state of the solar corona using global solar-surface magnetic-field maps created from Helioseismic and Magnetic Imager (HMI) full-disk magnetogram data. With the assumption of a polytropic gas with specific-heat ratio of 1.05, three types of simulation products are currently generated: i) simulation data with medium spatial resolution using the definitive calibrated synoptic map of the magnetic field with a cadence of one Carrington rotation, ii) data with low spatial resolution using the definitive version of the synchronic frame format of the magnetic field, with a cadence of one day, and iii) low-resolution data using near-real-time (NRT) synchronic format of the magnetic field on a daily basis. The MHD data available in the JSOC database are three-dimensional, covering heliocentric distances from 1.025 to 4.975 solar radii, and contain all eight MHD variables: the plasma density, temperature, and three components of motion velocity, and three components of the magnetic field. This article describes details of the MHD simulations as well as the production of the input magnetic-field maps, and details of the products available at the JSOC database interface. To assess the merits and limits of the model, we show the simulated data in early 2011 and compare with the actual coronal features observed by the Atmospheric Imaging Assembly (AIA) and the near-Earth in-situ data.

10.
Pflugers Arch ; 465(8): 1181-96, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23503725

RESUMO

Myoblast differentiation is mediated by a cascade of changes in gene expression including transcription factors such as myogenin. Subsequent to myoblast differentiation, there is an increase in expression of the transmembrane protein NADPH oxidase (Nox). Nox is one of the primary factors for the generation of reactive oxygen species (ROS) in myogenic (C2C12) cells. Recently, ROS have been shown to be important regulators of several intracellular signaling pathways, and the full extent of their regulatory roles is yet to be discovered. In the present study, qRT PCR analysis demonstrated that Nox4 isoform is primarily expressed in differentiating C2C12 cells and contributes to the generation of ROS in C2C12 myoblast during differentiation. Over-expression and silencing of Nox4 expression during myoblast differentiation was accompanied by a reduction in intracellular ROS concentrations and an alteration in the expression patterns of Myf5, Pax7, MyoD1, and myogenin. This modulation was found to be associated with ERK1/2 phosphorylation. In both over-expression and reduced expression of Nox4, we found significant reductions in ERK1/2 phosphorylation. This indicates that cellular differentiation may be affected by Nox4-mediated endogenous ROS generation. These data suggest a new opportunity to study the temporal expression of Nox4 in the generation of ROS accompanying changes in myogenic differentiation.


Assuntos
Biomarcadores/metabolismo , Diferenciação Celular/genética , Expressão Gênica/genética , Mioblastos/metabolismo , NADPH Oxidases/genética , Animais , Linhagem Celular , Regulação para Baixo/genética , Sistema de Sinalização das MAP Quinases/genética , Camundongos , Proteína MyoD/genética , Proteína MyoD/metabolismo , Fator Regulador Miogênico 5/genética , Fator Regulador Miogênico 5/metabolismo , Miogenina/genética , Miogenina/metabolismo , NADPH Oxidase 4 , NADPH Oxidases/metabolismo , Fator de Transcrição PAX7/genética , Fator de Transcrição PAX7/metabolismo , Fosforilação/genética , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Espécies Reativas de Oxigênio/metabolismo
11.
J Clin Monit Comput ; 26(4): 295-304, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22614336

RESUMO

With the increasing use of anaesthesia information management systems (AIMS) there is the opportunity for different institutions to aggregate and share information both nationally and internationally. Potential uses of such aggregated data include outcomes research, benchmarking and improvement in clinical practice and patient safety. However, these goals can only be achieved if data contained in records from different sources are truly comparable and there is semantic inter-operability. This paper describes the development of a standard terminology for anaesthesia and also a Domain Analysis Model and implementation guide to facilitate a standard representation of AIMS records as extensible markup language documents that are compliant with the Health Level 7 Version 3 clinical document architecture. A representation of vital signs that is compliant with the International Standards Organization 11073 standard is also discussed.


Assuntos
Anestesia/normas , Redes de Comunicação de Computadores/normas , Documentação/normas , Registros Eletrônicos de Saúde/normas , Registros de Saúde Pessoal , Registro Médico Coordenado/normas , Guias de Prática Clínica como Assunto
12.
An. pediatr. (2003, Ed. impr.) ; 74(1): 31-37, ene. 2011. tab, ilus
Artigo em Espanhol | IBECS | ID: ibc-90248

RESUMO

Introducción: La enfermedad mieloproliferativa transitoria neonatal y la leucemia aguda megacarioblástica del síndrome de Down se consideran manifestaciones distintas de la misma enfermedad. La mayoría de casos de enfermedad mieloproliferativa transitoria no requiere tratamiento mientras que la leucemia aguda megacarioblástica del síndrome de Down se caracteriza por una elevada sensibilidad a la quimioterapia, lo que ha llevado a la reducción en la intensidad de dosis de tratamiento administrada. Ambas entidades comparten mutaciones específicas en los exones 2 y 3,1 del factor de transcripción GATA1. Pacientes y métodos: Hemos analizado los hallazgos biológicos incluyendo la presencia de mutaciones de GATA1 en cuatro pacientes con enfermedad mieloproliferativa transitoria neonatal (2) y leucemia aguda megacarioblástica (2) incluyendo un paciente fenotípicamente normal portador de un mosaicismo para la trisomía 21. Resultados: En los cuatro casos hemos encontrado la presencia de una clona GATA1 mutante y en tres de ellos se describe una mutación puntual en el exón 2 de dicho gen. Dada la heterogeneidad fenotípica de los blastos megacariocíticos y el bajo porcentaje de estos elementos, la detección de mutaciones en GATA1 resultó de gran utilidad para establecer el diagnóstico. Además, sucesivos resultados normales del análisis mutacional de GATA1 permitieron establecer la remisión molecular en 2 pacientes. Conclusiones: Concluimos que el análisis mutacional de GATA1 es una herramienta útil para el diagnóstico y manejo de los trastornos mieloproliferativos asociados a la trisomía 21 (AU)


Introduction: Neonatal transient myeloproliferative disorder and acute megakaryoblastic leukaemia of Down syndrome are considered different manifestations of the same disease. In most cases, transient myeloproliferative disorders require no treatment, while acute megakaryoblastic leukaemia of Down's syndrome is characterised by an increased sensitivity to chemotherapy and its treatment should be adapted with a reduction in dose intensity. Both entities share specific mutations at exón 2 of the transcription factor GATA1. Patients and methods: We analysed biological features and GATA1 mutations in 4 patients with transient abnormal myelopoiesis (2) and acute megakaryoblastic leukaemia (2) including one phenotypically normal trisomy 21 mosaicism. We found abnormal GATA1 mutated clones in each case, and a specific point mutation at exón 2 was detected in three cases. Given the heterogeneous phenotype of megakaryoblastic blasts and the low percentage of blasts at presentation, the recognition of GATA1 mutations was helpful for diagnosis. In addition, molecular remission was established in 2 patients after subsequent normal mutational GATA1 analysis. Conclusions: We conclude that GATA1 mutational study is a useful tool for the diagnosis and management of trisomy 21 associated myeloproliferative disorders (AU)


Assuntos
Humanos , Transtornos Mieloproliferativos/fisiopatologia , Fator de Transcrição GATA1/análise , Síndrome de Down/fisiopatologia , Leucemia Megacarioblástica Aguda/fisiopatologia
13.
An Pediatr (Barc) ; 74(1): 31-7, 2011 Jan.
Artigo em Espanhol | MEDLINE | ID: mdl-20870473

RESUMO

INTRODUCTION: Neonatal transient myeloproliferative disorder and acute megakaryoblastic leukaemia of Down syndrome are considered different manifestations of the same disease. In most cases, transient myeloproliferative disorders require no treatment, while acute megakaryoblastic leukaemia of Down's syndrome is characterised by an increased sensitivity to chemotherapy and its treatment should be adapted with a reduction in dose intensity. Both entities share specific mutations at exón 2 of the transcription factor GATA1. PATIENTS AND METHODS: We analysed biological features and GATA1 mutations in 4 patients with transient abnormal myelopoiesis (2) and acute megakaryoblastic leukaemia (2) including one phenotypically normal trisomy 21 mosaicism. We found abnormal GATA1 mutated clones in each case, and a specific point mutation at exón 2 was detected in three cases. Given the heterogeneous phenotype of megakaryoblastic blasts and the low percentage of blasts at presentation, the recognition of GATA1 mutations was helpful for diagnosis. In addition, molecular remission was established in 2 patients after subsequent normal mutational GATA1 analysis. CONCLUSIONS: We conclude that GATA1 mutational study is a useful tool for the diagnosis and management of trisomy 21 associated myeloproliferative disorders.


Assuntos
Síndrome de Down/complicações , Fator de Transcrição GATA1/genética , Mutação , Transtornos Mieloproliferativos/etiologia , Transtornos Mieloproliferativos/genética , Pré-Escolar , Humanos , Lactente , Recém-Nascido
14.
J Laryngol Otol ; 124(1): 67-72, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19852868

RESUMO

OBJECTIVE: To evaluate the peri-operative usefulness of dexmedetomidine in obstructive sleep apnoea surgery. METHODS: In a clinical audit, patients were divided into a study group (dexmedetomidine used; n = 125; 82.9 per cent males, 17.1 per cent females; mean age 48.1 years) and a control group (dexmedetomidine not used; n = 143; 85.5 per cent males, 14.5 per cent females; mean age 47.4 years). The selected outcome measures were mean arterial pressure, use of anti-hypertensives and use of opioids. RESULTS: Mean arterial pressure was stable (i.e. below 100 mmHg) in 93.3 per cent of the study group and 72.0 per cent of the control group (relative risk 1.30, 95 per cent confidence interval 1.14-1.47). The use of glyceryl trinitrate and hydralazine was significantly less in the study group, compared with controls (p = 0.005 and <0.001, respectively). Study group patients underwent more procedures than control patients (p < 0.001) and were more likely to require morphine. No difference was noted in the median dose of opioids. CONCLUSION: Dexmedetomidine improves haemodynamic stability in patients undergoing surgery for obstructive sleep apnoea. It is reliable and reduces the need for polypharmacy. Its opioid-sparing action has been established in the literature; however, this was not demonstrated in our study.


Assuntos
Anestesia Geral/métodos , Dexmedetomidina/uso terapêutico , Hipnóticos e Sedativos/uso terapêutico , Apneia Obstrutiva do Sono/cirurgia , Adulto , Pressão Sanguínea , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Otorrinolaringológicos/métodos , Assistência Perioperatória , Apneia Obstrutiva do Sono/fisiopatologia
15.
Parasitology ; 135(4): 473-84, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18215335

RESUMO

Competition between parasite species has been predicted to be an important force shaping parasite and host ecology and evolution, although empirical data are often lacking. Using the Mus musculus-Schistosoma mansoni and Schistosoma rodhaini host-parasite systems we characterized mate choice and inter-specific competition between these two schistosome species. Simultaneous infections revealed species-specific mate preferences for both species as well as suggesting mating competition, with male S. rodhaini appearing dominant over male S. mansoni. S. rodhaini homologous pairs were also shown to have increased reproduction per paired female in the presence of a competitor in simultaneous infections. Overall total reproductive success was, however, similar between the two species under conditions of direct competition due to the greater initial infectivity of S. mansoni in comparison to S. rodhaini. Inter-specific competition was also implicated as increased parasite virulence to the host. The potential effects of such interactions on parasite and host ecology and evolution in nature are discussed.


Assuntos
Interações Hospedeiro-Parasita/fisiologia , Schistosoma mansoni/fisiologia , Esquistossomose mansoni/parasitologia , Animais , DNA de Helmintos/química , DNA de Helmintos/genética , DNA Intergênico/química , DNA Intergênico/genética , Feminino , Fígado/parasitologia , Masculino , Camundongos , Reação em Cadeia da Polimerase , Reprodução , Análise de Sequência de DNA , Especificidade da Espécie , Baço/parasitologia , Virulência
16.
Clin Oncol (R Coll Radiol) ; 20(2): 142-7, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18093813

RESUMO

AIMS: Palliative chemotherapy in non-small cell lung cancer (NSCLC) has been established since 1995 and little chemotherapy treatment was given to these patients before 1990. This retrospective study investigates the treatment outcome of elderly patients (age>or=70 years) with NSCLC over the past 13 years in a large UK cancer centre. MATERIALS AND METHODS: A comparison of all-cause survival between the time periods 1990-1994, 1995-1999 and 2000-2004 was adjusted for age, gender, stage and performance status. A comparison of survival was also made between three age groups: 70-74, 75-79 and 80+ years. RESULTS: Between 1990 and 2004, 302 patients>or=70 years had NSCLC. There were differences in age and performance status between the time periods. There was no improvement in median survival between the three time periods (P=0.6). There was little difference in outcome between the three age cohorts. CONCLUSIONS: The analysis shows that there has been no significant improvement in survival for elderly patients with advanced lung cancer treated with chemotherapy in the past 13 years.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Estudos Retrospectivos , Análise de Sobrevida , Fatores de Tempo , Resultado do Tratamento
17.
Leukemia ; 21(7): 1514-20, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17495976

RESUMO

Single-nucleotide polymorphism (SNP) array analysis was performed using the 10K GeneChip array on a series of 26 paired follicular lymphoma (FL) and transformed-FL (t-FL) biopsies and the lymphoma cell lines SCI-1, DoHH2 and RL2261. Regions of acquired homozygosity were detected in 43/52 (83%) primary specimens with a mean of 1.7 and 3.0 aberrations in the FL and t-FL, respectively. A notable feature was the occurrence of recurring sites of acquired uniparental disomy (aUDP) on 6p, 9p, 12q and 17p in cell lines and primary samples. Homozygosity of 9p and 17p arose predominantly in t-FL and in three cases rendered the cell homozygous for a pre-existing mutation of either CDKN2A or TP53. These data suggest that mutation precedes mitotic recombination, which leads to the removal of the remaining wild-type allele. In all, 18 cases exhibited abnormalities in both FL and t-FL samples. In 10 cases blocks of homozygosity were detected in FL that were absent in the subsequent t-FL sample. These differences support the notion that FL and t-FL may arise in a proportion of patients by divergence from a common malignant ancestor cell rather than by clonal evolution from an antecedent FL.


Assuntos
Genoma Humano/genética , Linfoma Folicular/genética , Dissomia Uniparental , Adulto , Idoso , Linhagem Celular Transformada , Cromossomos , Homozigoto , Humanos , Pessoa de Meia-Idade , Mutação , Análise de Sequência com Séries de Oligonucleotídeos , Polimorfismo de Nucleotídeo Único , Recombinação Genética
18.
Eye (Lond) ; 20(10): 1186-8, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17019417

RESUMO

AIMS: To describe the value of monoclonal antibodies in the differential diagnosis of orbital lymphoproliferative disorders. METHODS: A total of 200 sequential cases of malignant lymphoma diagnosed at St Bartholomew's Hospital as part of the ocular lymphoma service at Moorfields Eye Hospital and the Institute of Ophthalmology have been examined. Cases were acquired between January 1998 and June 2005. Each case had detailed immunophenotypic analysis using a panel of monoclonal antibodies and was classified using the WHO classification of lymphoma. These cases are discussed in relation to earlier studies of orbital lymphoma reported by our group. RESULTS: Lymphomas fell into three main categories. Extranodal marginal zone lymphoma was the largest group with 151 cases, arising within the orbital soft tissue, conjunctiva and lacrimal gland. Cases arising in the conjunctiva and lacrimal gland showed a higher female predominance than those arising within the deeper soft tissue. A small number of cases were associated with organ specific autoimmunity, including thyroid eye disease complicating Graves' disease. Follicular lymphoma and diffuse large B-cell lymphoma formed the next two groups, occurring with equal frequency. Many of the follicular lymphomas had evidence of disseminated disease on completion of staging. A miscellaneous group of T-cell and B-cell lymphomas formed a minority of cases during the study period. CONCLUSION: Extranodal marginal zone lymphoma is the most frequent type of primary orbital and orbital adnexal lymphoma. Its major differential diagnosis is with orbital lymphoid hyperplasia, chronic dacryoadenitis, and follicular conjunctivitis. Systemic types of lymphoma may present within the orbit or involve the orbit secondarily.


Assuntos
Linfoma/diagnóstico , Neoplasias Orbitárias/diagnóstico , Anticorpos Monoclonais , Antígenos de Neoplasias/análise , Neoplasias da Túnica Conjuntiva/diagnóstico , Neoplasias da Túnica Conjuntiva/imunologia , Diagnóstico Diferencial , Humanos , Imunofenotipagem , Doenças do Aparelho Lacrimal/diagnóstico , Doenças do Aparelho Lacrimal/imunologia , Linfoma/imunologia , Linfoma de Células B/diagnóstico , Linfoma de Células B/imunologia , Neoplasias Orbitárias/imunologia
20.
Br J Cancer ; 94(1): 18-21, 2006 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-16317431

RESUMO

Platinum-based treatment for small cell lung cancer (SCLC) has been established since 1995. This study investigates treatment outcome of elderly patients (age >/=70 years) with SCLC over the past 20 years in a large UK cancer centre. Comparison of all-cause survival was assessed in patients presenting between two predefined time periods: 1982-1994 and 1995-2003. All the survival analysis were adjusted for stage and performance status and age if appropriate. Survival between different chemotherapy treatment regimens was compared. A total of 322 elderly patients (31% of all) registered between 1982-2003 received chemotherapy for SCLC. Patients presenting in 1995-2003 had an overall better median survival (43 vs 25 weeks) and a 1-year survival (37 vs 14%) than patients presenting in 1982-1994 (P<0.001). This applied to patients with both limited and extensive stage disease and all age groups. There was a trend towards the use of more platinum-based treatments in the later cohort but the use of radiotherapy remained constant. Patients who received platinum combinations (Carboplatin or Cisplatin) had significantly improved survival over those who received single agents or other combinations (P<0.001) and there was no significant difference between carboplatin and cisplatin (P=0.7). The analysis demonstrates that there has been a significant improvement in survival for elderly patients with lung cancer treated by chemotherapy in the past 20 years despite more very elderly patients being treated with a poorer performance status. This change is probably multifactorial and may be due to the increased use of platinum-based treatment and improved supportive care.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma de Células Pequenas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Carboplatina/administração & dosagem , Cisplatino/administração & dosagem , Esquema de Medicação , Feminino , Humanos , Masculino , Estudos Retrospectivos , Análise de Sobrevida , Resultado do Tratamento
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