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BACKGROUND: During the early part of the COVID-19 pandemic, the Canadian Society of Otolaryngology - Head & Neck Surgery (CSO-HNS) task force published recommendations on performance of tracheotomy. Since then, our understanding of the virus has evolved with ongoing intensive research efforts. New literature has helped us better understand various aspects including patient outcomes and health care worker (HCW) risks associated with tracheotomy during the COVID-19 pandemic. Accordingly, the task force has re-evaluated and revised some of the previous recommendations. MAIN BODY: Based on recent evidence, a negative reverse transcription polymerase chain reaction (RT-PCR) COVID-19 swab status is no longer the main deciding factor in the timing of tracheotomy. Instead, tracheotomy may be considered as soon as COVID-19 swab positive patients are greater than 20 days beyond initial symptoms and 2 weeks of mechanical ventilation. Furthermore, both open and percutaneous surgical techniques may be considered with both techniques showing similar safety and outcome profiles. Additional recommendations with discussion of current evidence are presented. CONCLUSION: These revised recommendations apply new evidence in optimizing patient and health care system outcomes as well as minimizing risks of COVID-19 transmission during aerosol-generating tracheotomy procedures. As previously noted, additional evidence may lead to further evolution of these and other similar recommendations.
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COVID-19/prevenção & controle , Controle de Infecções , Otolaringologia , Traqueotomia , COVID-19/diagnóstico , COVID-19/transmissão , Canadá , Cuidados Críticos , Humanos , Transmissão de Doença Infecciosa do Paciente para o Profissional/prevenção & controle , Seleção de Pacientes , Guias de Prática Clínica como AssuntoRESUMO
INTRODUCTION: Persons with haemophilia and other inherited bleeding disorders are prone to disabling joint arthropathy frequently requiring arthroplasty for end-stage joint disease. Higher complication rates and more modest post-operative functional outcomes have previously been described. AIM: To evaluate the clinical outcomes and patient satisfaction of persons with inherited bleeding disorders (predominantly haemophilia) undergoing total hip and knee replacement. METHODS: Retrospective, single-centre cohort study with longitudinal assessment of patients with inherited bleeding disorders who underwent total hip and knee replacement over a 20-year period. Eligible patients were clinically assessed with Harris Hip Score (HHS), Knee Society Score (KSS), pain visual analogue scale (VAS) and a patient satisfaction questionnaire. RESULTS: Thirty-one patients (48 joints) met the inclusion criteria. Mean age at surgery was 49.3 years (SD: 13.1, range 21-75 years) with a mean follow-up of 9.33 years (1.7-19.3). The majority (26/31) of patients had haemophilia A, predominantly severe haemophilia A (22/26). Reported pain levels were low, and patient satisfaction was high. Joint-specific outcome scores were "good" to "excellent" in 67% of total hip replacement patients and 92% of total knee replacement patients. A low complication rate was observed, with 2 patients requiring revision surgery and 4 patients requiring re-operation without implant revision. CONCLUSION: Arthroplasty is a reliable procedure in patients with inherited bleeding disorders with end-stage hip or knee arthropathy. The overall complexity of this group is highlighted, and the need for multidisciplinary care is emphasised.
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Artroplastia de Quadril/métodos , Artroplastia do Joelho/métodos , Hemorragia/complicações , Qualidade de Vida/psicologia , Adulto , Idoso , Feminino , Hemorragia/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Satisfação do Paciente , Resultado do Tratamento , Adulto JovemRESUMO
BACKGROUND: Laryngeal injury after blunt trauma is uncommon, but can cause catastrophic airway obstruction and significant morbidity in voice and airway function. This paper aims to discuss a case series of sports-related blunt laryngeal trauma patients and describe the results of a thorough literature review. METHOD: Retrospective case-based analysis of laryngeal trauma referrals over six years to a tertiary laryngology centre. RESULTS: Twenty-eight patients were identified; 13 (46 per cent) sustained sports-related trauma. Most were young males, presenting with dysphonia, some with airway compromise (62 per cent). Nine patients were diagnosed with a laryngeal fracture. Four patients were managed conservatively and nine underwent surgery. Post-treatment, the majority of patients achieved good voice outcomes (83 per cent) and all had normal airway function. CONCLUSION: Sports-related neck trauma can cause significant injury to the laryngeal framework and endolaryngeal soft tissues, and most cases require surgical intervention. Clinical presentation may be subtle; a systematic approach along with a high index of suspicion is essential, as early diagnosis and treatment have been reported to improve airway and voice outcome.
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Obstrução das Vias Respiratórias/etiologia , Traumatismos em Atletas/complicações , Laringe/lesões , Lesões do Pescoço/etiologia , Ferimentos não Penetrantes/complicações , Adolescente , Adulto , Obstrução das Vias Respiratórias/cirurgia , Traumatismos em Atletas/cirurgia , Disfonia/etiologia , Disfonia/cirurgia , Feminino , Humanos , Laringe/cirurgia , Masculino , Pessoa de Meia-Idade , Lesões do Pescoço/cirurgia , Ontário , Estudos Retrospectivos , Resultado do Tratamento , Ferimentos não Penetrantes/cirurgia , Adulto JovemRESUMO
INTRODUCTION In the 75-80% of urothelial bladder cancers (UBC) presenting as non-muscle invasive bladder cancer (NMIBC), transurethral resection of bladder tumour (TURBT) is the key treatment and staging procedure. In the 20-25% of patients with muscle invasive bladder cancer (MIBC), further cross-sectional imaging is required to complete the staging process before considering radical treatment. Given the adverse effects of ionising radiation, clinicians identify patients believed to have MIBC, and so requiring further imaging pre-TURBT, at the tumour histology/stage based on the tumour's visual characteristics. There is minimal evidence describing the accuracy of such predictions in newly-diagnosed patients. METHODS Over a 6-year period, a database of patients undergoing resection of newly-diagnosed bladder lesions in a single UK centre was prospectively established. Predictions based on histology were simultaneously recorded, and the accuracy of these predictions of histology/stage subsequently assessed. RESULTS One hundred and twenty two (73.1%) patients with histologically confirmed NMIBC had predictions recorded versus 45 (26.9%) patients with MIBC. Visual assessment predictions of MIBC had a sensitivity of 88.9% (95% confidence interval [CI] 76.5%-95.2%) and a specificity of 91.0% (95% CI 84.6%-94.9%), giving a positive predictive value of 78.4% (95% CI 65.4%-87.5%) and a negative predictive value of 95.7% (95% CI 90.3%-98.1%). CONCLUSIONS We find that visual assessment is accurate in predicting the presence of MIBC. This supports the practice of stratifying patients at the time of initial cystoscopy for those requiring further radiological staging pre-TURBT.
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Cistoscopia , Estadiamento de Neoplasias/métodos , Neoplasias da Bexiga Urinária/patologia , Humanos , Invasividade Neoplásica/patologia , Estudos Prospectivos , Sensibilidade e Especificidade , Bexiga Urinária/patologia , Neoplasias da Bexiga Urinária/diagnósticoRESUMO
Radiation-induced skin injury during fluoroscopic procedures has been recently addressed by The Joint Commission, which defined prolonged fluoroscopy resulting in a cumulative peak skin dose of ≥15 Gy to a single field as a sentinel event (FSE). Neuroendovascular procedures can be associated with a high radiation skin dose and present risks such as potential FSEs. Managing these risks is the responsibility of the interventional neuroradiologist. In this review, we discuss hospital policies needed for screening and preventing FSEs, methods for minimizing radiation-induced skin injury, and actions necessary to address potential FSEs once they have occurred.
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Procedimentos Endovasculares/efeitos adversos , Fluoroscopia/efeitos adversos , Procedimentos Neurocirúrgicos/efeitos adversos , Proteção Radiológica/métodos , Radiodermite/etiologia , Radiodermite/prevenção & controle , Radiografia Intervencionista/efeitos adversos , Fluoroscopia/métodos , Humanos , Monitorização Intraoperatória/métodos , Radiografia Intervencionista/métodos , Vigilância de Evento Sentinela , Pele/lesões , Pele/efeitos da radiaçãoRESUMO
PURPOSE: To review and compare different approaches to the problem of dosimetry for limited field-of-view (FOV) cone beam CT devices for dental and maxillofacial applications. METHODS: The determination of patient doses from specialized, cone-beam CT devices for dental and maxillofacial work requires medical physicists to re-evaluate their dosimetry methods. These devices work in cone-beam geometry, with an axial field dimension on the order of the lengths of the standard head CTDI phantom and pencil ionization chamber. They may also utilize less than 360 degree scans, resulting in asymmetrical radiation distributions. This operating regime is far from that for which conventional CT dosimetry was designed, and alternative approaches must be considered. The alternatives include extensions of conventional CT dosimetry currently used for large axial FOV scanners (e.g. the extended CTDI parameter (CTDIe) for the Toshiba Aquillion One with 160 mm axial FOV) and the new method based on point dosimetry measurements recently formalized in AAPM Report TG-111. Conventional, modified-conventional, and TG-111 dosimetry measurements are used in two CT dose phantoms (adult head and pediatric head) to obtain dose indices for the Planmeca ProMax 3D Max dental CT scanner. Surface dose maps are generated using radiochromic film for correlation with the chamber dosimetry. RESULTS: Results for the three dosimetry approaches are compared for the specific case of the ProMax 3D Max scanner. Strengths and weaknesses of the three measurement paradigms for this type of application are compared. CONCLUSIONS: The increasing availability of specialized scanners operating in full cone-beam mode will require the clinical medical physicist to be conversant with extensions to the CT dose index methodology suitable for this equipment.
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OBJECTIVES: Gynaecological cancer is common. It is highly amenable to effective treatment, but thrombosis remains a common complication. There is controversy about whether microparticles (MPs), particularly tissue factor (TF) positive MPs, are increased in patients with malignancy and/or thrombosis. We therefore set out to investigate the relationship between MPs of different cellular origins, in patients with gynaecological malignancy. We hypothesised that patients with gynaecological malignancy have increased numbers of MPs. We measured MPs released by different cell types in these patients, and correlated the results with measures of haemostatic activation. METHODS: We measured the number of platelet-derived MPs (PMPs), endothelial cell-derived MPs (EMPs), leucocyte-derived MPs (LMPs), TF+ve MPs and annexin V (AV) binding MPs in fresh plasma by flow cytometry in patients with gynaecological malignancy and a control group. We also measured D-dimers, prothrombin fragments 1 and 2 (PF1&2) and thrombin-antithrombin (TAT) complexes as indirect markers of haemostatic activation. RESULTS: The number of MPs (from all cell types) was similar in the two patient groups, with no significant differences. The number of circulating TF+ve MPs was also similar between the two groups. D-dimers (p<0.001) and PF1&2 (p=0.009) were significantly higher in the malignant group reflecting haemostatic activation, but there was no correlation between the level of D-dimers, PF1&2 and TAT and MP numbers. CONCLUSION: Using fresh samples, MPs were not significantly increased in patients with gynaecological malignancy. There was, however, evidence of haemostatic activation in the patients with malignancy, but no correlation between the number of MPs and haemostatic activation.
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Micropartículas Derivadas de Células/metabolismo , Neoplasias dos Genitais Femininos/sangue , Antitrombina III/metabolismo , Estudos de Casos e Controles , Micropartículas Derivadas de Células/patologia , Feminino , Produtos de Degradação da Fibrina e do Fibrinogênio/metabolismo , Citometria de Fluxo , Neoplasias dos Genitais Femininos/patologia , Humanos , Fragmentos de Peptídeos/metabolismo , Peptídeo Hidrolases/metabolismo , Precursores de Proteínas/metabolismo , Protrombina/metabolismo , Trombina/metabolismoRESUMO
BACKGROUND: We describe a severe form of congenital myasthenic syndrome (CMS) associated with congenital nephrosis and ocular malformations caused by two truncating mutations in the gene encoding the laminin beta2 subunit (LAMB2). METHODS AND RESULTS: Mutational analysis in the affected patient, who has a history of a serious untoward reaction to treatment with acetylcholinesterase inhibition, revealed two frame-shifting heteroallelic mutations, a maternally inherited 1478delG and a paternally inherited 4804delC. An anconeus muscle biopsy demonstrated a profound distortion of the architecture and function of the neuromuscular junction, which was strikingly similar to that seen in mice lacking laminin beta2 subunit. The findings included: pronounced reduction of the axon terminal size with encasement of the nerve endings by Schwann cells, severe widening of the primary synaptic cleft and invasion of the synaptic space by the processes of Schwann cells, and moderate simplification of postsynaptic folds and intact expression of the endplate acetylcholinesterase. The endplate potential quantal content was notably reduced, while the frequencies and amplitudes of miniature endplate potentials were only moderately diminished and the decay phases of miniature endplate potentials were normal. Western blot analysis of muscle and kidney tissue and immunohistochemistry of kidney tissue showed no laminin beta2 expression. CONCLUSION: This case, which represents a new type of synaptic CMS, exemplifies the wide variability of phenotypes associated with LAMB2 mutations and underscores the fundamental role that laminin beta2 plays in the development of the human neuromuscular junction.
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Laminina/genética , Mutação , Síndromes Miastênicas Congênitas/genética , Análise Mutacional de DNA , Oftalmopatias Hereditárias/genética , Feminino , Humanos , Síndromes Miastênicas Congênitas/diagnóstico , Síndromes Miastênicas Congênitas/fisiopatologia , Junção Neuromuscular/ultraestrutura , Adulto JovemRESUMO
Cardiac surgery for coronary heart disease, and for calcific and degenerative valvular heart disease, will likely become more frequent with an ageing haemophilia population. Our report describes the successful management of an individual with mild haemophilia B undergoing elective aortic valve replacement using a continuous infusion of recombinant factor IX. Emphasis is placed on the multidisciplinary coordination of care required across three hospital sites to ensure an uncomplicated peri- and postoperative course. We also provide a review of the current literature on cardiac surgery in patients with haemophilia B.
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Estenose da Valva Aórtica/cirurgia , Valva Aórtica/cirurgia , Implante de Prótese de Valva Cardíaca , Hemofilia B/tratamento farmacológico , Estenose da Valva Aórtica/complicações , Fator IX/administração & dosagem , Fator IX/uso terapêutico , Hemofilia B/complicações , Hemostasia Cirúrgica/métodos , Humanos , Infusões Intravenosas , Masculino , Pessoa de Meia-Idade , Assistência Perioperatória/métodos , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/uso terapêuticoRESUMO
Increasing evidence is emerging highlighting the role of parathyroid hormone-related protein (PTHrP) during metastasis by regulating cell adhesion. The current study demonstrated that modulation of PTHrP expression by PTHrP overexpression and small interfering RNA-induced silencing resulted in changes in cell adhesion and integrin expression. RNA interference of endogenous PTHrP caused a significant reduction in cell adhesion of a breast cancer cell line to collagen type I, fibronectin and laminin (P<0.05) and of a colon cancer cell to collagen type I and fibronectin (P<0.05). Overexpression of PTHrP induced a significant increase in cell adhesion of colon (P<0.0001) and breast (P<0.05) cancer cells to the same extracellular matrix proteins. These PTHrP-mediated effects were attributed to changes in integrin expression as the differences in adhesion profile correlated with the integrin expression profile. In an attempt to elucidate the mechanism whereby PTHrP regulates integrin expression, promoter activity of the integrin alpha5 subunit was analysed and significant increases in transcriptional activity were observed in PTHrP overexpressing cells (P<0.0001), which was dependent on nuclear localisation. These results indicate that modulation of cell adhesion is a normal physiological action of PTHrP, mediated by increasing integrin gene transcription.
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Integrina alfa5/genética , Proteína Relacionada ao Hormônio Paratireóideo/fisiologia , Transcrição Gênica , Adenocarcinoma , Neoplasias da Mama , Linhagem Celular Tumoral , Neoplasias do Colo , Feminino , Citometria de Fluxo , Regulação Neoplásica da Expressão Gênica , Humanos , Proteína Relacionada ao Hormônio Paratireóideo/genética , Subunidades Proteicas/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , TransfecçãoRESUMO
Stickler Syndrome is an infrequent autosomal dominant connective tissue disorder. The most prevalent mutation affects type II collagen gene and results in abnormalities in cartilage, vitreous and nucleus pulposus. Orthopaedic manifestations include joint hyper- mobility and pain with early development of secondary osteoarthritis. The condition has a predilection for the femoral head and patients usually present in their third to fourth decade with secondary hip arthritis. We report on two siblings with Stickler Syndrome who presented with hip osteoarthritis in their third decade of life and underwent staged bilateral total hip arthroplasties (THA). The patients experienced pain relief and improved quality of life after surgery.
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Tecido Adiposo/metabolismo , Hidrocarboneto de Aril Hidroxilases/genética , Arilsulfotransferase/genética , Oxigenases de Função Mista/genética , Escatol/metabolismo , Suínos/genética , Alelos , Animais , Composição Corporal/genética , Mapeamento Cromossômico , Citocromo P-450 CYP2A6 , Ligação Genética , Marcadores Genéticos , Genótipo , Repetições de Microssatélites , Polimorfismo de Nucleotídeo Único , Locos de Características Quantitativas , Suínos/anatomia & histologia , Suínos/metabolismoRESUMO
We report the case of a patient with severe chronic obstructive pulmonary disease who underwent local resection of a carcinoma of the rectum under spinal anaesthesia. Although the patient was keen to avoid general anaesthesia and to have the operation under a spinal anaesthetic, pre-operative assessment showed that he could not lie flat. As the surgical procedure required the patient to be in the lithotomy position, ideally with a head-down tilt, it was hoped that continuous positive airway pressure with a facemask during spinal anaesthesia might help him to tolerate the position comfortably. Continuous positive airway pressure at 7.5 cmH(2)O was successfully used to facilitate breathing during surgery under spinal anaesthesia. A combination of regional anaesthesia and continuous positive airway pressure via a facemask is easy to use and may be a useful option in the management of these challenging patients.
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Raquianestesia , Pressão Positiva Contínua nas Vias Aéreas/métodos , Cuidados Intraoperatórios/métodos , Doença Pulmonar Obstrutiva Crônica/terapia , Idoso , Decúbito Inclinado com Rebaixamento da Cabeça , Humanos , Masculino , Neoplasias Retais/cirurgiaRESUMO
The US Wheat Genome Project, funded by the National Science Foundation, developed the first large public Triticeae expressed sequence tag (EST) resource. Altogether, 116,272 ESTs were produced, comprising 100,674 5' ESTs and 15 598 3' ESTs. These ESTs were derived from 42 cDNA libraries, which were created from hexaploid bread wheat (Triticum aestivum L.) and its close relatives, including diploid wheat (T. monococcum L. and Aegilops speltoides L.), tetraploid wheat (T. turgidum L.), and rye (Secale cereale L.), using tissues collected from various stages of plant growth and development and under diverse regimes of abiotic and biotic stress treatments. ESTs were assembled into 18,876 contigs and 23,034 singletons, or 41,910 wheat unigenes. Over 90% of the contigs contained fewer than 10 EST members, implying that the ESTs represented a diverse selection of genes and that genes expressed at low and moderate to high levels were well sampled. Statistical methods were used to study the correlation of gene expression patterns, based on the ESTs clustered in the 1536 contigs that contained at least 10 5' EST members and thus representing the most abundant genes expressed in wheat. Analysis further identified genes in wheat that were significantly upregulated (p < 0.05) in tissues under various abiotic stresses when compared with control tissues. Though the function annotation cannot be assigned for many of these genes, it is likely that they play a role associated with the stress response. This study predicted the possible functionality for 4% of total wheat unigenes, which leaves the remaining 96% with their functional roles and expression patterns largely unknown. Nonetheless, the EST data generated in this project provide a diverse and rich source for gene discovery in wheat.
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Etiquetas de Sequências Expressas , Perfilação da Expressão Gênica , Triticum/genética , Triticum/metabolismo , Análise por Conglomerados , Mapeamento de Sequências Contíguas , Coleta de Dados , Bases de Dados Genéticas , Biblioteca Gênica , Genes de Plantas , Filogenia , Poliploidia , Distribuição Tecidual , Triticum/crescimento & desenvolvimentoRESUMO
We present the case of a patient with acquired von Willebrand's syndrome and a monoclonal gammopathy of undetermined significance who required cystectomy for relapsed transitional cell carcinoma (TCC) of the bladder. We demonstrated that infused von Willebrand factor (VWF) containing factor VIII concentrates had an unacceptably short half-life, but that this was significantly prolonged following combined therapy with plasma exchange and intravenous immunoglobulin (IVIgG). This approach was successfully utilized peri-operatively, with the total surgical blood loss less than would be expected even for a haemostatically normal patient. Trough VWF antigen and Ristocetin co-factor activity levels fell on the second postoperative day and we therefore administered further IVIgG. Levels again fell on the fifth postoperative day with the development of a Staphylococcus aureus septicaemia. At this point bleeding occurred from a surgical drain site requiring 'factor VIII inhibitor bypass activity' to secure haemostasis while further plasma exchange and IVIgG were administered. Now 5 years later, there is no evidence of recurrence of the TCC or progression of the monoclonal gammopathy.
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Carcinoma de Células de Transição/cirurgia , Neoplasias da Bexiga Urinária/cirurgia , Doenças de von Willebrand/tratamento farmacológico , Perda Sanguínea Cirúrgica/prevenção & controle , Carcinoma de Células de Transição/complicações , Fator VIII/uso terapêutico , Humanos , Imunoglobulinas Intravenosas/uso terapêutico , Masculino , Pessoa de Meia-Idade , Troca Plasmática/métodos , Resultado do Tratamento , Neoplasias da Bexiga Urinária/complicações , Fator de von Willebrand/uso terapêuticoRESUMO
BACKGROUND: Clinical studies suggest that inhaled corticosteroids reduce exacerbations and improve health status in chronic obstructive pulmonary disease (COPD). However, their effect on mortality is unknown. METHODS: A pooled analysis, based on intention to treat, of individual patient data from seven randomised trials (involving 5085 patients) was performed in which the effects of inhaled corticosteroids and placebo were compared over at least 12 months in patients with stable COPD. The end point was all-cause mortality. RESULTS: Overall, 4% of the participants died during a mean follow up period of 26 months. Inhaled corticosteroids reduced all-cause mortality by about 25% relative to placebo. Stratification by individual trials and adjustments for age, sex, baseline post-bronchodilator percentage predicted forced expiratory volume in 1 second, smoking status, and body mass index did not materially change the results (adjusted hazard ratio (HR) 0.73; 95% confidence interval (CI) 0.55 to 0.96). Although there was considerable overlap between subgroups in terms of effect sizes, the beneficial effect was especially noticeable in women (adjusted HR 0.46; 95% CI 0.24 to 0.91) and former smokers (adjusted HR 0.60; 95% CI 0.39 to 0.93). CONCLUSIONS: Inhaled corticosteroids reduce all-cause mortality in COPD. Further studies are required to determine whether the survival benefits persist beyond 2-3 years.
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Corticosteroides/administração & dosagem , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Administração por Inalação , Causas de Morte , Feminino , Volume Expiratório Forçado/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Doença Pulmonar Obstrutiva Crônica/mortalidade , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Ensaios Clínicos Controlados Aleatórios como Assunto , Análise de SobrevidaRESUMO
There is no information in the literature regarding the lymphocyte content or type in bone marrow biopsies from patients with "idiopathic" pure red cell aplasia (PRCA). This report describes the bone marrow biopsy sections of a patient with PRCA. A diffuse CD3 positive (CD8 positive, granzyme B negative) lymphocytosis of approximately 1500/mm3 was revealed by immunohistochemical staining. The extent of the T cell increase was not evident from morphological examination of the bone marrow aspirate or biopsy, from flow cytometric analysis of the aspirate, or from the peripheral blood lymphocyte count. Therefore, immunohistochemical analysis should be performed routinely in this rare disease and the data acquired may help to inform the choice of treatment.
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Linfócitos T CD8-Positivos/imunologia , Linfocitose/imunologia , Aplasia Pura de Série Vermelha/imunologia , Adulto , Células da Medula Óssea/imunologia , Exame de Medula Óssea , Humanos , Linfocitose/etiologia , Masculino , Aplasia Pura de Série Vermelha/complicaçõesRESUMO
Because of the huge size of the common wheat (Triticum aestivum L., 2n = 6x = 42, AABBDD) genome of 17,300 Mb, sequencing and mapping of the expressed portion is a logical first step for gene discovery. Here we report mapping of 7104 expressed sequence tag (EST) unigenes by Southern hybridization into a chromosome bin map using a set of wheat aneuploids and deletion stocks. Each EST detected a mean of 4.8 restriction fragments and 2.8 loci. More loci were mapped in the B genome (5774) than in the A (5173) or D (5146) genomes. The EST density was significantly higher for the D genome than for the A or B. In general, EST density increased relative to the physical distance from the centromere. The majority of EST-dense regions are in the distal parts of chromosomes. Most of the agronomically important genes are located in EST-dense regions. The chromosome bin map of ESTs is a unique resource for SNP analysis, comparative mapping, structural and functional analysis, and polyploid evolution, as well as providing a framework for constructing a sequence-ready, BAC-contig map of the wheat genome.
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Mapeamento Cromossômico , Cromossomos de Plantas/genética , Etiquetas de Sequências Expressas , Genes de Plantas , Genoma de Planta , Triticum/genética , Marcadores Genéticos , Ploidias , Locos de Características Quantitativas , Alinhamento de SequênciaRESUMO
BACKGROUND: A trial of corticosteroids has been recommended for all patients with chronic obstructive pulmonary disease (COPD), with the subsequent "response" determining the treatment selected. This approach assumes that patients can be reliably divided into responder and non-responder groups. We have assessed whether such a separation is statistically valid, which factors influence the change in forced expiratory volume in 1 second (FEV(1)) after prednisolone, and whether the prednisolone response predicts 3 year changes in FEV(1), health status, or number of exacerbations during placebo or fluticasone propionate treatment. METHODS: Oral prednisolone 0.6 mg/kg was given for 14 days to 524 patients with COPD before randomised treatment for 3 years with fluticasone propionate or placebo. Factors relating to change in FEV(1) after prednisolone were investigated using multiple regression. The response to prednisolone was entered into separate mixed effects models of decline in FEV(1) and health status during the 3 years of the study. RESULTS: The post-bronchodilator FEV(1) increased by a mean 60 ml (CI 46 to 74) after prednisolone with a wide unimodal distribution. Current smoking was the factor most strongly associated with the change in FEV(1) after prednisolone, with an increase of 35 ml in current smokers and 74 ml in confirmed ex-smokers (p<0.001). There was no relationship between the change in FEV(1) after prednisolone and the response to inhaled bronchodilators, baseline FEV(1), atopic status, age, or sex. The response to prednisolone, however expressed, was unrelated to the subsequent change in FEV(1) over the following 3 years on either placebo or fluticasone propionate. Regression to the mean effects explained much of the apparent prednisolone response. The significant effect of treatment on decline in health status was not predicted by the prednisolone response. CONCLUSION: Patients with COPD cannot be separated into discrete groups of corticosteroid responders and non-responders. Current smoking reduces the FEV(1) response to prednisolone. Prednisolone testing is an unreliable predictor of the benefit from inhaled fluticasone propionate in individual patients.
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Glucocorticoides , Prednisolona , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Administração Oral , Androstadienos/uso terapêutico , Broncodilatadores/uso terapêutico , Feminino , Fluticasona , Volume Expiratório Forçado/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Capacidade Vital/efeitos dos fármacosRESUMO
BACKGROUND: A limited or absent bronchodilator response is used to classify chronic obstructive pulmonary disease (COPD) and can determine the treatment offered. The reliability of the recommended response criteria and their relationship to disease progression has not been established. METHODS: 660 patients meeting European Respiratory Society (ERS) diagnostic criteria for irreversible COPD were studied. Spirometric parameters were measured on three occasions before and after salbutamol and ipratropium bromide sequentially or in combination over 2 months. Responses were classified using the American Thoracic Society/GOLD (ATS) and ERS criteria. Patients were followed for 3 years with post-bronchodilator FEV(1) and exacerbation history recorded 3 monthly and health status 6 monthly. RESULTS: FEV(1) increased significantly with each bronchodilator, a response that was normally distributed. Mean post-bronchodilator FEV(1) was reproducible between visits (intraclass correlation 0.93). The absolute change in FEV(1) was independent of the pre-bronchodilator value but the percentage change correlated with pre-bronchodilator FEV(1) (r=-0.44; p<0.0001). Using ATS criteria, 52.1% of patients changed responder status between visits compared with 38.2% using ERS criteria. Smoking status, atopy, and withdrawing inhaled corticosteroids were unrelated to bronchodilator response, as was the rate of decline in FEV(1), decline in health status, and exacerbation rate. CONCLUSION: In moderate to severe COPD bronchodilator responsiveness is a continuous variable. Classifying patients as "responders" and "non-responders" can be misleading and does not predict disease progression.