RESUMO
BACKGROUND: The rare inversa subtype of recessive dystrophic epidermolysis bullosa (RDEB-I) is characterized by predominant intertriginous skin blistering and marked mucosal involvement. Specific recessive missense mutations in the collagen VII triple helix are implicated in the disease. To date, otological complications have been reported infrequently in this patient group. METHODS: We conducted an observational, retrospective, double institution case record review of patients with RDEB-I who presented with otological complications between January 2000 and June 2020. Diagnosis was established on the basis of clinical features, family history and mutation analysis of the COL7A1 gene. RESULTS: In total, 11 (44%) of 25 patients with RDEB-I in our database (2 paediatric, 9 adult; mean age 40.9 years, range 8-72 years) experienced otological complications. Of these 11 patients, 10 (90.9%) had recurrent otitis externa, 7 (63.6%) had meatal stenosis and 7 (63.6%) had recurrent blistering of the external auditory canals. All 11 patients reported hearing difficulties, with conductive hearing loss confirmed by audiology testing in 6 (54.5%) of these. Of the 11 patients, 3 (27.3%) went on to have implantable hearing aids [2 bone-anchored hearing aids (BAHA) and 1 middle ear implant (MEI)] fitted with favourable outcome, while a fourth paediatric patient presented with a cholesteatoma that was surgically managed. DISCUSSION: We observed a higher prevalence of otological morbidity in RDEB-I than previously reported, and present the first case of cholesteatoma in epidermolysis bullosa (EB). Our data indicate that BAHA and MEI are safe and effective treatment options for hearing loss in EB. Clinicians should be vigilant in screening for ear symptoms in RDEB-I and consider early referral to an Ear, Nose and Throat specialist.
Assuntos
Epidermólise Bolhosa Distrófica , Epidermólise Bolhosa , Adolescente , Adulto , Idoso , Criança , Colágeno Tipo VII/genética , Epidermólise Bolhosa/genética , Epidermólise Bolhosa Distrófica/complicações , Epidermólise Bolhosa Distrófica/genética , Genes Recessivos , Humanos , Pessoa de Meia-Idade , Mutação de Sentido Incorreto , Estudos Retrospectivos , Adulto JovemRESUMO
Accurate prediction of premorbid functioning is important in neuropsychological assessment. We aimed to investigate the predictive accuracy of the TOPF and examine this word list at an item level against WASI-II scores, using Australian pronunciations. The sample of 219 healthy Australians were aged 18-82 years. Multiple regression analyses were used to replicate the TOPF and simple demographic models based on the US TOPF standardization. Rasch analyses provided a comparison of Australian, US and UK word order from the proportion of words pronounced correctly. The variance explained in WASI-II index scores ranged from R2=.12 (PRI) to .33 (FSIQ-2), which was approximately half that reported in the US standardization study. The accuracy of predicted WASI-II scores was also slightly less in our sample. Thirty-two words were out of place by five places or more compared with the US word order and 30 compared with the UK. These results add to concerns about the application the TOPF with norms developed in the US and UK in the Australian context. Clinicians are advised not to apply the five error discontinue rule when using the TOPF in the local context. Development of a more accurate word reading task for use in Australia is warranted.
Assuntos
Inteligência , Leitura , Austrália , Humanos , Testes de Inteligência , Testes Neuropsicológicos , Escalas de WechslerRESUMO
Quality of life is a key indicator of outcome following traumatic brain injury (TBI). Research has reported several different factor structures for the Quality of Life Inventory (QOLI, Frisch, 1994). We compared the fit of existing factor models and examined the clinical utility of the QOLI's factors in a sample of Australian adults with TBI. Archival data from 901 participants were provided by the Neurotrauma Register of Tasmania. Participants were aged 16-80 years and 63% were male. Approximately 69% had mild TBI (PTA < 24â h), approximately 24% had moderate TBI (PTA >1â day, <7 days) and 7% had severe TBI. Both cross sectional and longitudinal analyses were utilized, as participants provided data at one or more of seven time-points, up to 3 years following injury. The results showed the data best fitted a three-factor model, comprising Self-functioning and activity, Self-actualization and Family and environment factors, and a second order Overall QOL factor. Differences in the trajectory of recovery were noted between the QOLI factor scores over time and in relation to demographic and injury variables. In conclusion, the three-factor structure of the QOLI provided useful clinical information about the recovery of patients' subjective quality of life following TBI.
Assuntos
Lesões Encefálicas Traumáticas/reabilitação , Avaliação de Resultados em Cuidados de Saúde/normas , Psicometria/normas , Qualidade de Vida , Sistema de Registros , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Concussão Encefálica/epidemiologia , Concussão Encefálica/reabilitação , Lesões Encefálicas Traumáticas/epidemiologia , Estudos Transversais , Análise Fatorial , Humanos , Estudos Longitudinais , Pessoa de Meia-Idade , Psicometria/instrumentação , Tasmânia/epidemiologia , Adulto JovemRESUMO
PRIMARY OBJECTIVE: To examine loss to follow-up (LTFU) using a population with traumatic brain injury (TBI) to include a range of severity and to follow participants to 3 years post-injury. Also investigated were cause of TBI and employment status. RESEARCH DESIGN: The research included 947 adults from a TBI population study. Data were obtained on severity, cause of TBI and employment status and participants were followed up at 1, 3, 6, 12, 24 and 36 months after injury. Chi-squared analyses were used to examine rates of loss to follow-up. MAIN OUTCOME AND RESULTS: Overall LTFU increased from 22% at 1 month post-injury to 81% at 3-year follow-up. Most participants (52%) were employed at the time of their TBI, with 39% of TBIs being motor vehicle related. Lower LTFU at 2 and 3 years post-TBI was significantly associated with severe TBI. Within the mTBI sub-group significantly higher LTFU at 1 and 6 months after injury and at 2 and 3 years post-injury was associated with TBI from assault. Those sustaining mTBI from a fall or sport-related injury showed significantly lower LTFU at the 6-month, 12-month and 2-year follow-up points. The highest LTFU was noted for unemployed participants, with retired participants showing the lowest rate.
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Lesões Encefálicas/epidemiologia , Emprego/estatística & dados numéricos , Pacientes Desistentes do Tratamento/estatística & dados numéricos , Viés , Lesões Encefálicas/etiologia , Feminino , Seguimentos , Nível de Saúde , Humanos , Estudos Longitudinais , Masculino , Pacientes Desistentes do Tratamento/classificação , Inquéritos e Questionários , Tasmânia/epidemiologia , Índices de Gravidade do TraumaRESUMO
PRIMARY OBJECTIVE: To compare the pre-injury subjective quality of life (SQOL) estimates of a representative sample of adults with TBI, using the Quality of Life Inventory (QOLI) with the measure's generic US-based norms and identify a factor structure for the instrument within the local TBI population. RESEARCH DESIGN: A population-based, cross-sectional design conducted with data collected by the Neurotrauma Register of Tasmania (2003-2005). METHODS AND PROCEDURES: As soon as possible following their emergence from post-traumatic amnesia, 470 participants provided pre-injury estimates of their SQOL using the QOLI. The distribution of this sample was compared with the measure's normative distribution. The sample was separated evenly into two groups (n = 235) for separate exploratory and confirmatory factor analyses. MAIN OUTCOMES AND RESULTS: Small differences were found between the pre-injury estimates and the QOLI's US-based normative distribution. Corrections were provided to clinical classification ranges for this population. Three factors were identified and confirmed for the QOLI in separate TBI samples. CONCLUSION: The results of this study support the use of the QOLI in measuring SQOL in TBI rehabilitation and outcomes research.
Assuntos
Lesões Encefálicas/psicologia , Qualidade de Vida/psicologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Lesões Encefálicas/reabilitação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Psicometria , Fatores de Risco , Índice de Gravidade de Doença , Tasmânia , Resultado do Tratamento , Adulto JovemRESUMO
There is uncertainty as to the rates of coal fly ash needed for optimum physiological processes and growth. In the current study we tested the hypothesis that photosynthetic pigments concentrations and CO(2) assimilation (A) are more sensitive than dry weights in plants grown on media amended with coal fly ash. We applied the Terrestrial Plant Growth Test (Guideline 208) protocols of the Organization for Economic Cooperation and Development (OECD) to monocots [barley (Hordeum vulgare) and ryegrass (Secale cereale)] and dicots [canola (Brasica napus), radish (Raphanus sativus), field peas (Pisum sativum), and lucerne (Medicago sativa)] on media amended with fly ashes derived from semi-bituminous (gray ash) or lignite (red ash) coals at rates of 0, 2.5, 5.0, 10, or 20 Mg ha(-1). The red ash had higher elemental concentrations and salinity than the gray ash. Fly ash addition had no significant effect on germination by any of the six species. At moderate rates (= 10 Mg ha(-1)) both ashes increased (p < 0.05) growth rates and concentrations of chlorophylls a and b, but reduced carotenoid concentrations. Addition of either ash increased A in radish and transpiration in barley. Growth rates and final dry weights were reduced for all of the six test species when addition rates exceeded 10 Mg ha(-1) for gray ash and 5 Mg ha(-1) for red ash. We concluded that plant dry weights, rather than pigment concentrations and/or instantaneous rates of photosynthesis, are more consistent for assessing subsequent growth in plants supplied with fly ash.
Assuntos
Carbono , Carvão Mineral , Produtos Agrícolas/crescimento & desenvolvimento , Material Particulado , Fotossíntese , Pigmentos Biológicos/análise , Cinza de Carvão , GerminaçãoRESUMO
INTRODUCTION: Sinus drainage is impeded by the transition spaces that the anterior paranasal sinuses drain into, not the ostia themselves. Addressing the transition spaces and leaving the ostia intact, using the minimally invasive sinus technique, should reverse chronic rhinosinusitis. AIM: To assess patient benefit following use of the minimally invasive sinus technique for chronic rhinosinusitis. METHOD: One hundred and forty-three consecutive patients underwent the minimally invasive sinus technique for chronic rhinosinusitis. Symptoms (i.e. blocked nose, poor sense of smell, rhinorrhoea, post-nasal drip, facial pain and sneezing) were recorded using a visual analogue scale, pre-operatively and at six and 12 weeks post-operatively. Patients were also surveyed using the Glasgow benefit inventory, one and three years post-operatively. RESULTS: We found a significant reduction in all nasal symptom scores at six and 12 weeks post-operatively, and increased total quality of life scores at one and three years post-operatively (25.2 and 14.8, respectively). CONCLUSION: The patient benefits of treatment with the minimally invasive sinus technique compare with the published patient benefits for functional endoscopic sinus surgery.
Assuntos
Endoscopia , Sinusite/cirurgia , Doença Crônica , Drenagem/métodos , Feminino , Humanos , Masculino , Satisfação do Paciente , Qualidade de Vida/psicologia , Índice de Gravidade de Doença , Sinusite/psicologia , Resultado do TratamentoRESUMO
OBJECTIVES: A variety of paediatric tracheostomy tubes are available. This article reviews those in current use at Great Ormond Street Hospital. METHODS: We outline our preferences and the particular indications for the different tubes, speaking valves and other attachments. RESULTS: Practice has changed significantly in recent years. One product has been re-sized by its manufacturer; others are no longer commonly used. An updated sizing chart is included for reference purposes, together with manufacturers' contact details. CONCLUSIONS: The choice of paediatric tracheostomy tube is driven by clinical requirements. A small range of tubes are suitable for the majority of children, but some will require other varieties in specific circumstances.
Assuntos
Intubação/instrumentação , Traqueostomia/instrumentação , Criança , Pré-Escolar , Tomada de Decisões , Desenho de Equipamento/normas , Feminino , Seguimentos , Humanos , Lactente , Recém-Nascido , Intubação/métodos , Masculino , Prática Profissional , Traqueostomia/métodos , Resultado do TratamentoRESUMO
OBJECTIVES: When introduced, suction coagulation was initially utilised for haemorrhage control following curettage of the adenoid pad. More recently the whole procedure has been performed using the technique. This study aims to report post-operative haemorrhage rates and risk of recurrence in adenoidectomy performed solely by suction diathermy in children. METHODS: A retrospective study of 1411 consecutive paediatric patients. Surgery was performed using suction diathermy. No patients were excluded. All patients were followed up. RESULTS: There were no cases of post-operative haemorrhage. 1.7% of patients remained symptomatic and underwent revision adenoidectomy. None required a third procedure. CONCLUSIONS: Re-growth of adenoid tissue may occur despite visualisation of the nasopharynx at the time of surgery. The incidence of re-growth is similar to that reported in patients undergoing conventional adenoidectomy by curettage. Post-operative haemorrhage was not encountered in children having adenoidectomy by suction diathermy. The authors suggest suction diathermy as the most appropriate method for adenoidectomy in children.
Assuntos
Adenoidectomia/métodos , Eletrocoagulação/métodos , Hemorragia Pós-Operatória/etiologia , Adenoidectomia/efeitos adversos , Tonsila Faríngea/fisiopatologia , Adolescente , Criança , Pré-Escolar , Eletrocoagulação/efeitos adversos , Feminino , Seguimentos , Humanos , Lactente , Masculino , Ventilação da Orelha Média , Otite Média com Derrame/cirurgia , Recidiva , Estudos Retrospectivos , Fatores de Risco , Fatores Sexuais , Apneia Obstrutiva do Sono/cirurgia , Sucção , Tonsilectomia , Tonsilite/cirurgia , Membrana Timpânica/cirurgiaRESUMO
OBJECTIVES: Obstructive sleep apnoea is a common childhood disorder. Adenotonsillar enlargement is most commonly implicated, with adenotonsillectomy representing an effective treatment in the majority of cases. Such children may develop respiratory compromise post-operatively, sometimes necessitating admission to the intensive care unit. We describe insertion of a nasopharyngeal "prong" airway and evaluate its benefits after adenotonsillectomy for obstructive sleep apnoea and milder forms of sleep-disordered breathing. METHODS: The prong is easily fashioned from a paediatric endotracheal tube. It is inserted once surgery is complete, remaining in situ overnight. We retrospectively examine its elective use over an 18-month period in selected children considered to be at high risk of post-operative respiratory compromise. Existing practice over the preceding 18-month period is also examined, by way of comparison. RESULTS: Forty-three children underwent adenotonsillectomy for sleep-disordered breathing/OSAS in the 18 months prior to introduction of the prong. Ten were considered "high risk" cases: post-operative intensive care beds were pre-booked for these, but none were eventually required. During the subsequent 18 months, 60 children underwent adenotonsillectomy for the same indication. Seventeen "high risk" cases received the prong post-operatively. No intensive care beds were pre-booked and all children were managed safely on the ENT ward, with minimal intervention. CONCLUSIONS: Use of a nasopharyngeal prong significantly improves the post-operative course of selected children who are at high risk of respiratory compromise after adenotonsillectomy. This largely avoids the need for medical intervention and intensive care admission.
Assuntos
Adenoidectomia/instrumentação , Intubação/instrumentação , Nasofaringe , Insuficiência Respiratória/prevenção & controle , Apneia Obstrutiva do Sono/cirurgia , Tonsilectomia/instrumentação , Adenoidectomia/efeitos adversos , Adolescente , Criança , Pré-Escolar , Seguimentos , Humanos , Lactente , Insuficiência Respiratória/etiologia , Estudos Retrospectivos , Tonsilectomia/efeitos adversos , Resultado do TratamentoRESUMO
Thyroid lobectomy with isthmusectomy is the standard surgical technique for removal of unilateral thyroid nodules, and it involves the exposure of the tracheoesophageal grooves. Thyroid isthmusectomy is a surgical procedure that excises only the thyroid isthmus. It allows excision of a lesion without the exposure of the tracheoesophageal grooves. We aimed to demonstrate that isthmusectomy could be a safe alternative to thyroid lobectomy with isthmusectomy in patients with nodules confined to the isthmus or the pyramidal lobe. This was a prospective study performed over a five year period from 1999 to 2004. Inclusion criteria for thyroid isthmusectomy were: patients with a single lesion located in the region of the thyroid isthmus or the pyramidal lobe; maximum lesion diameter of 30 mm; and cytological reports of non-diagnostic appearance, follicular cells or suspicion of malignancy. Nine patients were identified with these criteria. Histology included two colloid nodules, three benign follicular adenomas, two Hurthle cell adenomas and two papillary thyroid carcinomas. There were no recorded complications. Thyroid isthmusectomy is a safe alternative to thyroid lobectomy with isthmusectomy in patients who have nodules confined to the isthmus and pyramidal lobe. Leaving a cuff of normal thyroid tissue has the advantage of not exposing the tracheoesophageal grooves, thus minimising potential damage to the recurrent laryngeal nerves and parathyroids. Surgeons performing isthmusectomies should be experienced in more complex thyroid surgical procedures.
Assuntos
Neoplasias da Glândula Tireoide/cirurgia , Tireoidectomia/métodos , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Resultado do TratamentoRESUMO
Diverse microbial communities and numerous energy-yielding activities occur in deeply buried sediments of the eastern Pacific Ocean. Distributions of metabolic activities often deviate from the standard model. Rates of activities, cell concentrations, and populations of cultured bacteria vary consistently from one subseafloor environment to another. Net rates of major activities principally rely on electron acceptors and electron donors from the photosynthetic surface world. At open-ocean sites, nitrate and oxygen are supplied to the deepest sedimentary communities through the underlying basaltic aquifer. In turn, these sedimentary communities may supply dissolved electron donors and nutrients to the underlying crustal biosphere.
Assuntos
Bactérias/metabolismo , Ecossistema , Sedimentos Geológicos/microbiologia , Bactérias/crescimento & desenvolvimento , Bactérias/isolamento & purificação , Carbono/metabolismo , Contagem de Colônia Microbiana , Transporte de Elétrons , Ferro/metabolismo , Manganês/metabolismo , Metano/metabolismo , Nitratos/metabolismo , Oxidantes/metabolismo , Oxirredução , Oceano Pacífico , Peru , Fotossíntese , Água do Mar/química , Sulfatos/metabolismo , TermodinâmicaRESUMO
Muscle fine structure and metabolism were examined in four species of Antarctic fishes that vary in their expression of haemoglobin (Hb). To determine how locomotory pectoral muscles maintain function, metabolic capacity, capillary supply and fibre ultrastructure were examined in two nototheniid species that express Hb (Notothenia coriiceps and Gobionotothen gibberifrons) and two species of channichthyid icefish that lack Hb (Chaenocephalus aceratus and Chionodraco rastrospinosus). Surprisingly, icefish have higher densities of mitochondria than red-blooded species (C. aceratus, 53+/-3% of cell volume; C. rastrospinosus, 39+/-3%; N. coriiceps, 29+/-3%; G. gibberifrons, 25+/-1%). Despite higher mitochondrial densities the aerobic metabolic capacities per g wet mass, estimated from measurements of maximal activities of key metabolic enzymes, are lower in icefish compared to red-blooded species. This apparent incongruity can be explained by the significantly lower mitochondrial cristae surface area per unit mitochondrion volume in icefishes (C. aceratus, 20.8+/-1.6 microm(-1); C. rastrospinosus, 25.5+/-1.8 microm(-1)) compared to red-blooded species (N. coriiceps, 33.6+/-3.0 microm(-1); G. gibberifrons, 37.7+/-3.6 microm(-1)). Consequently, the cristae surface area per unit muscle mass is conserved at approximately 9 m(2)g(-1). Although high mitochondrial densities in icefish muscle do not enhance aerobic metabolic capacity, they may facilitate intracellular oxygen movement because oxygen is more soluble in lipid, including the hydrocarbon core of intracellular membrane systems, than in aqueous cytoplasm. This may be particularly vital in icefish, which have larger oxidative muscle fibres compared to red-blooded nototheniods (C. aceratus, 2932+/-428 microm(2); C. rastrospinosus, 9352+/-318 microm(2); N. coriiceps, 1843+/-312 microm(2); G. gibberifrons, 2103+/-194 microm(2)). These large fibres contribute to a relatively low capillary density, which is partially compensated for in icefish by a high index of tortuosity in the capillary bed (C. aceratus=1.4, N. coriiceps=1.1).
Assuntos
Peixes/anatomia & histologia , Peixes/metabolismo , Músculo Esquelético/anatomia & histologia , Músculo Esquelético/metabolismo , Aerobiose , Animais , Regiões Antárticas , Capilares/anatomia & histologia , Hemoglobinas/metabolismo , Microscopia Eletrônica , Mitocôndrias Musculares/ultraestrutura , Fibras Musculares Esqueléticas/metabolismo , Fibras Musculares Esqueléticas/ultraestrutura , Músculo Esquelético/irrigação sanguínea , Oxirredução , Oxigênio/metabolismo , Natação/fisiologiaRESUMO
Transcellular oxygen flux was modelled mathematically in the aerobic skeletal muscles of perciform fish species living at widely different temperatures (Antarctica, sub-Antarctica and the Mediterranean Sea). Using structural data derived from stereological analysis of electron micrographs, mean fibre P(O(2)) was calculated on the basis of temperature-corrected rates of mitochondrial respiration and oxygen diffusion. The mean muscle fibre diameter (MFD) among Antarctic notothenioids was in the range 17-61 microm and mitochondrial volume density, Vv(mit,f), was 0.27-0.53, but capillary-to-fibre ratio varied only between 1.2 and 1.5. For a mean capillary P(O(2)) of 6 kPa, the model predicted a mean tissue P(O(2)) in the range 0.7-5.8 kPa at the estimated maximum aerobic capacity (M(O(2)max)). The lowest levels of tissue oxygenation were found in the pectoral muscle fibres of the icefish Chaenocephalus aceratus, which lacks the respiratory pigments haemoglobin and myoglobin. Red-blooded notothenioids found in the sub-Antarctic had a similar muscle fine structure to those caught south of the Antarctic Convergence, with an MFD of 20-41 microm and Vv(mit,f) of 0.27-0.33, resulting in an estimated mean P(O(2)) of 4-5 kPa at M(O(2)max). Mean tissue P(O(2)) in the sub-Antarctic icefish Champsocephalus esox, with greater MFD and Vv(mit,f), 56 microm and 0.51, respectively, was calculated to exceed 1 kPa at winter temperatures (4 degrees C), although oxidative metabolism was predicted to be impaired at the summer maximum of 10 degrees C. At the high end of the thermal range, related perciform species from the Mediterranean had a negligible drop in intracellular P(O(2)) across their small-diameter fibres, to a minimum of 5.4 kPa, comparable with that predicted for Trematomus newnesi from the Antarctic (5.6 kPa) with a similar MFD. These data suggest that, within a single phylogenetic group, integrative structural adaptations potentially enable a similar degree of tissue oxygenation over a 20 degrees C range of environmental temperature in the red-blooded notothenioids, and that this is compromised by the lack of respiratory pigments in the icefishes. The mean capillary radius was 1.5 times greater in the two icefish than in the other notothenioids, and the model simulations indicate that the evolution of wide-bore capillaries is essential to maintain tissue oxygenation in the absence of respiratory pigments.
Assuntos
Músculo Esquelético/metabolismo , Consumo de Oxigênio , Perciformes/metabolismo , Animais , Regiões Antárticas , Capilares , Difusão , Matemática , Mar Mediterrâneo , Microscopia Eletrônica , Mitocôndrias Musculares/metabolismo , Modelos Biológicos , Músculo Esquelético/anatomia & histologia , Músculo Esquelético/irrigação sanguínea , Oxigênio/análise , TemperaturaRESUMO
We examined the hypothesis that disturbance of laminar flow promotes the attachment of leukocytes to the vessel wall in regions where the wall shear stress is otherwise too high. Isolated neutrophils, lymphocytes, or monocytes were perfused through chambers with backward-facing steps so that vortices occurred with well-defined reattachment of flow. Wall shear stresses downstream in reestablished flow equaled 0.07 Pa (low shear) or 0.3 Pa (high shear). In chambers coated with P-selectin, adherent leukocytes rolled. By use of a P-selectin-Fc fragment chimera, adhesion was predominantly stationary, enabling definition of initial attachment sites. Neutrophils adhered in all regions of the low-shear chamber, with a local maximum around the reattachment point. However, in the high-shear chamber, adhesion was restricted to the recirculation zone and immediately downstream from the reattachment point. Rolling at high shear stress allowed a population of regions where initial attachment could not occur. At high shear, lymphocytes and monocytes also formed attachments restricted to the region of the reattachment point. The results imply that all types of leukocytes might bind to a capture receptor in high-shear vessels with discontinuities in the wall and might then spread to other regions.
Assuntos
Vasos Sanguíneos/fisiologia , Adesão Celular/fisiologia , Leucócitos/fisiologia , Selectina-P/metabolismo , Reologia , Humanos , Fragmentos Fc das Imunoglobulinas , Leucócitos Mononucleares/fisiologia , Modelos Biológicos , Neutrófilos/fisiologia , Proteínas Recombinantes de Fusão , Fluxo Sanguíneo Regional/fisiologiaRESUMO
We have recently described patterns of adhesion of different types of leukocytes downstream of a backward facing step. Here the predicted fluid dynamics in channels incorporating backward facing steps are described, and related to the measured velocities of flowing cells, patterns of attachment and characteristics of rolling adhesion for neutrophils perfused over P-selectin. Deeper (upstream depth 300 microm, downstream depth 600 microm, maximum wall shear stress approximately 0.1 Pa) and shallower (upstream depth 260 microm, downstream depth 450 microm, maximum wall shear stress approximately 0.3 Pa) channels were compared. Computational fluid dynamics (CFD) predicted the presence of vortices downstream of the steps, distances to reattachment of flow, local wall shear stresses and components of velocity parallel and perpendicular to the wall. Measurements of velocities of perfused neutrophils agreed well with predictions, and suggested that adhesion to P-selectin should be possible in the regions of recirculating flow, but not downstream in re-established flow in the high shear channel. When channels were coated with a P-selectin-Fc chimaera, neutrophils were captured from flow and immobilised. Capture showed local maxima around the reattachment points, but was absent elsewhere in the high shear chamber. In the low shear chamber there was depression of adhesion just beyond the reattachment point because of expansion of flow and depletion of neutrophils near the wall. Inside the recirculation zones, adhesion decreased approaching the step because of an increasing, vertically upward velocity component. When channels were coated with P-selectin, neutrophils rolled in all regions, but lifted off the surface as they rolled backwards into low shear regions near the step. Rolling velocity in the recirculation zone was independent of shear stress, possibly because of the effects of vertical lift. We conclude that while local wall shear stress influences adhesive behavior, delivery of cells to the wall and their behavior after capture also depend on components of flow perpendicular to the wall.
Assuntos
Hemorreologia , Neutrófilos/fisiologia , Velocidade do Fluxo Sanguíneo/fisiologia , Adesão Celular/fisiologia , Endotélio Vascular/fisiologia , Humanos , Neutrófilos/metabolismo , Selectina-P/metabolismo , Estresse MecânicoRESUMO
Seasonal changes in ultrastructure of locomotory muscle were quantified after acclimatization to natural temperature and photoperiod. Only modest changes were seen in the volume density (V(v)) of mitochondria in slow fibers ranging from 0.21 +/- 0.01 (summer) to 0.24 +/- 0.01 (winter), despite an increase in fiber size from 945 +/- 19 to 1,594 +/- 46 microm(2), respectively, resulting in a significantly greater total mitochondrial volume at low temperatures. In contrast, intracellular lipid stores showed a marked change with season, from a maximum V(v) of lipid droplets of 0.16 +/- 0.01 in winter, progressively declining through spring and summer to a minimum of 0.07 +/- 0.01 in autumn. For both organelles, the surface density reflected changes in V(v), indicating little modification of structure. Seasonal effects may dominate those of environmental temperature on mitochondrial separation, which in winter and spring fish at 4(o)C averaged 0.64 +/- 0.06 and 1.20 +/- 0.07 microm, respectively. The extracellular transport of oxygen also varies with season, the peak capillary density in autumn (2,851 +/- 88 mm(-2)) resulting in a minimum tissue supply (domain) area of 529 +/- 9 microm(2) per capillary. As a consequence, the predicted intracellular PO(2) ( approximately 2.5 kPa) is similar throughout the year.
Assuntos
Aclimatação/fisiologia , Temperatura Alta , Músculo Esquelético/fisiologia , Oncorhynchus mykiss/fisiologia , Oxigênio/metabolismo , Estações do Ano , Animais , Transporte Biológico/fisiologia , Capilares/fisiologia , Membranas Intracelulares/fisiologia , Mitocôndrias Musculares/fisiologia , Músculo Esquelético/irrigação sanguínea , Músculo Esquelético/ultraestrutura , Organelas/fisiologia , Pressão Parcial , TemperaturaRESUMO
OBJECTIVE: To establish the feasibility and method of evaluation of an early supported hospital discharge policy for patients with acute stroke. DESIGN: A randomized controlled trial comparing an early supported discharge service to conventional care. SETTING: Three acute hospitals in Newcastle upon Tyne. SUBJECTS: Ninety-two eligible patients with acute stroke admitted between 1 February 1995 and 31 January 1996. MAIN OUTCOME MEASURES: Placement, length of stay, readmission rates, mortality, functional ability (Nottingham Extended Activities of Daily Living (ADL) Scale), handicap (Oxford Handicap Scale), global health status (Dartmouth Coop Function Charts) and carer stress (General Health Questionnaire 30 item). RESULTS: The median length of stay for patients randomized to early supported discharge was 13 days compared to 22 days in the conventional care group (p = 0.02). The median Barthel ADL index at seven days post stroke of patients randomized to early supported discharge was 15, and 13 for those randomized to conventional care (NS). At three months post stroke the median Nottingham EADL score of patients randomized to early supported discharge was 10 compared to 7 for those who received conventional care (NS). There were no statistically significant differences in the global health status of patients or carer stress. CONCLUSION: An early supported discharge service following acute stroke with individualized rehabilitation in the community is feasible and can be evaluated by a randomized controlled trial but a larger multicentre trial is needed before such a service is widely adopted.
Assuntos
Transtornos Cerebrovasculares/reabilitação , Tempo de Internação/estatística & dados numéricos , Avaliação de Resultados em Cuidados de Saúde/métodos , Alta do Paciente , Atividades Cotidianas , Adulto , Idoso , Idoso de 80 Anos ou mais , Transtornos Cerebrovasculares/mortalidade , Feminino , Política de Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Formulação de Políticas , Taxa de Sobrevida , Reino UnidoRESUMO
Data collected in a population-based study on 976 patients suffering an acute stroke have been analysed to discover the frequency of disturbance of selected cognitive functions, particularly orientation, non-verbal reasoning, and copying. Further analysis investigated how these deficits related to other impairments, their prognostic importance, and their recovery. Considering patients assessed within the first week, only 45% were orientated, only 44% could be assessed for IQ and their average score was 94 (SD 16), and only 36% could copy a cross satisfactorily. Seventeen per cent of patients had a reduced level of consciousness preventing assessment, and the other unassessable patients had other impairments such as aphasia preventing assessment. In general failure to pass these tests was associated with evidence of a more severe stroke; the patients had other impairments such as a more severe paralysis. No independent effect of cognitive dysfunction upon recovery could be demonstrated. By 6 months most surviving patients passed all the tests used.