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1.
NPJ Microgravity ; 10(1): 52, 2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38714711

RESUMEN

Sessile water droplet evaporation in varied gravity and electric fields has been experimentally studied. Specifically, the influences of gravity and electric fields are investigated in the context of the heat flux distribution beneath the droplets, as well as the droplet mechanics and resulting shapes. Experimental testing was carried out during a European Space Agency (ESA) Parabolic Flight Campaign (PFC 66). The droplets tested evaporated with a pinned contact line, a single wettability condition, and varied droplet volume and substrate heat flux. The peak heat transfer was located at the contact line for all cases. The peak heat flux, average heat flux, and droplet evaporation rate were shown to vary strongly with gravity, with higher values noted for hypergravity conditions and lower values in microgravity conditions. The droplet thermal inertia was shown to play a significant role, with larger droplets taking more time to reach thermal equilibrium during the parabolic testing period. No significant impact of the electric field on the droplet evaporation was noted for these test conditions.

2.
Clin Radiol ; 79(5): 323-329, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38429136

RESUMEN

Interstitial lung diseases (ILDs) are a heterogeneous group of conditions characterised by non-infective inflammation and scarring of the lung parenchyma. They are not infrequently encountered by the general radiologist in both acute and outpatient reporting settings who may even be the first to make the diagnosis. In the acute setting, patients with ILD can present with respiratory deterioration due to a number of causes and in addition to the common causes of dyspnoea, an acute exacerbation of ILD needs to be considered. An exacerbation can be initiated by common triggers such as infection, pulmonary embolism (PE), and heart failure, and it can also be initiated by an insult to the lung or occur due to an unknown cause. Particular care needs to be taken when interpreting computed tomography (CT) examinations in these patients as the findings of an acute exacerbation are non-specific and patient and technical factors can cause spurious appearances including dependent changes, breathing artefact and contrast medium opacification. In the non-acute setting, patients with ILD are at increased risk of lung cancer and pulmonary hypertension (PH), with lung cancer being a particularly important consideration as treatments carry the risk of triggering an acute exacerbation or deterioration in lung function. Overall, this review aims to provide an overview for the general radiologist of additional factors to consider when interpreting scans in patients with ILD and how the presence of ILD impacts the differential diagnoses and complications that can occur in these patients in both acute and non-acute settings.


Asunto(s)
Enfermedades Pulmonares Intersticiales , Neoplasias Pulmonares , Humanos , Enfermedades Pulmonares Intersticiales/diagnóstico por imagen , Enfermedades Pulmonares Intersticiales/complicaciones , Pulmón/diagnóstico por imagen , Pronóstico , Disnea , Progresión de la Enfermedad
3.
J Fish Biol ; 103(5): 1095-1105, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37436400

RESUMEN

Holohalaelurus regani and Scyliorhinus capensis are relatively small catsharks, which both occur off the continental shelf around South Africa and are often caught together as by-catch in demersal trawls. The present study used data collected during annual demersal research surveys conducted between 2009 and 2015 and is a first attempt at modeling the potential intra- and interspecific associations, by maturity stage and depth, of H. regani and S. capensis to elucidate species-specific patterns in their distributions in South African waters. Intraspecifically, both species displayed a wide overlap in distribution between maturity stages, but only H. regani displayed marked changes in distribution with maturity stage, with mature individuals found further eastwards and occupying deeper waters than immature individuals. Interspecifically, the two catsharks displayed an inverse relationship in their distribution, with an increase in the abundance of H. regani and a decrease in the abundance of S. capensis when moving from the south coast to the west coast. Some localized patches of co-occurrence were, however, evident between species and maturity stages, especially in offshore areas. Overall, our results indicated a stronger co-occurrence of mature and immature stages within each species and a rather weak co-occurrence of maturity stages between the two species. The spatial information provided in the present study provides useful information on how sharks with similar morphologies and lifestyles may partition their habitat as a mechanism for potentially reducing competition between them.


Asunto(s)
Ecosistema , Tiburones , Humanos , Animales , Sudáfrica , Especificidad de la Especie
4.
Ir J Psychol Med ; 40(4): 561-565, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36789630

RESUMEN

OBJECTIVES: To outline characteristics of patients with anxiety diagnoses attending a Specialist Perinatal Mental Health Service (SPMHS) in Ireland, the mental health care received by those patients, mental health and obstetric outcomes for those patients, and immediate neonatal outcomes for their babies. METHODS: A retrospective chart review was conducted of patients with antenatal anxiety diagnoses who attended the SPMHS in University Maternity Hospital Limerick, from initiation of the service to the end of its first year. RESULTS: Data were collected on 100 patients, 81 with a mental health diagnosis prior to attending the SPMHS, 32 with prior engagement with psychiatry, and 23 with a previous perinatal diagnosis. The mean age of patients was 32.4 (19-47, std 6.158). Beyond initial assessment, the Mental Health Midwife was involved in the care of 61% of patients, more than any other specialty including psychiatry. Twenty-seven patients had psychiatric medication either started or altered by the SPMHS. The most common reason for eventual discharge was that patients were well. Two patients presented in mental-health-related crisis to emergency services and one patient was admitted to an acute psychiatric ward. CONCLUSIONS: Patients attending the SPMHS for anxiety spanned a broad spectrum of demographics and diagnoses and received varied set of interventions. A significant proportion of patients had a primary diagnosis of Pregnancy-related anxiety. The Mental Health Midwife played a key role in management of these patients. Though rates of mental health crises and admissions were low, the absence of a Mother and Baby Unit in Ireland was highlighted.


Asunto(s)
Servicios de Salud Mental , Lactante , Recién Nacido , Embarazo , Femenino , Humanos , Estudios Retrospectivos , Hospitalización , Salud Mental , Ansiedad
5.
J Bone Oncol ; 30: 100390, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34589408

RESUMEN

BACKGROUND: The efficacy and safety of cell salvage for musculoskeletal sarcoma surgery have not been reported, and concerns over re-infusion of tumour cells remain. This study aims to i) describe the intra-operative blood loss and cell salvage reinfusion volumes for lower limb sarcoma and pelvic sarcoma procedures ii) and explore whether there is evidence of tumour cells in reinfused blood. METHODS: Retrospective analysis of 109 consecutive surgical procedures for biopsy-proven sarcoma or bone metastasis performed between 1 July 2015 and 30 October 2019. Salvaged blood was processed and reinfused when intraoperative blood loss exceeded 500 ml. Primary bone tumour (n = 86(79%)) and metastasis (n = 23(21%) constituted the study group and surgeries were classified under hemipelvectomy (n = 43(39%)), lower limb endoprosthesis replacement (LLE) (n = 50(46%)) and wide excision surgery (WE) (n = 16(15%)). Microscopic examination of imprint cytology of leuco-depletion(LD) filters, and peripheral smear examination was performed for reinfused blood. RESULTS: Median (IQR) intra-operative blood loss was 1750 (600-3000) ml for hemipelvectomy, 850 (600-1200) ml for LLE, and 1000 (550-2000) ml for WE. Salvaged blood was re-infused in 102 of 109 (94%) patients. The mean (SD) volume of re-infusion was 445(4 2 5) ml for hemipelvectomy, 206(1 3 1) ml for LLE, and 184(1 0 6) ml for WE. In total, 64 of 109 (59%) patients received an allogeneic red blood transfusion within 72 h of surgery. Cytology analysis of imprints taken from the filtered blood available in 95(87%) patients and peripheral smear examination of reinfused blood available in 32(29%) patients did not reveal evidence of tumour cells on microscopic examination of any samples. CONCLUSION: Our study demonstrates that musculoskeletal sarcoma surgery is associated with significant blood loss, and cell salvage permits reinfusion of autologous blood in most patients. The cytological analysis did not reveal evidence of tumour cells in reinfused blood, consistent with other studies where cell salvage is used for cancer surgery.

6.
Ann R Coll Surg Engl ; 103(10): 762-767, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34448646

RESUMEN

INTRODUCTION: Sarcomas of the head and neck are neoplasms arising from the embryonic mesenchyme. They are rare and heterogeneous in nature and are associated with significant morbidity and mortality. This study evaluates patients referred to the Oxford Sarcoma Service, a tertiary referral centre. METHODS: Patients discussed over a three-year period were included. Medical records were analysed using the electronic patient record database. Data were acquired on a range of domains, including: demographics, histopathology, treatment modality, recurrence, mortality, survival, etc. RESULTS: Thirty-two eligible patients, 21 male and 11 female, were identified with a mean age of 58 years; 26 out of 32 patients had high-grade sarcomas. The commonest histological subtype was chondrosarcoma (8/32). Twenty-two underwent planned multidisciplinary team surgical resection after biopsy and staging: negative margins were noted in 9, with close and involved margins in 5 and 8, respectively. Local recurrence was noted in 13 and 6 had metastatic disease out of the 32 eligible patients. Mortality was noted in 10 out of 32 patients. Mean survival was 69.5 months. Five-year overall survival was 64%. Surgery demonstrated statistically significant improvement in survival (p=0.0095). There were no significant differences in survival, recurrence or marginal status between methods of adjuvant or neoadjuvant therapy. CONCLUSION: Outcomes of head and neck sarcomas are inferior compared with other types of sarcoma. The nature of the complex surrounding anatomy presents unique challenges in surgical management. This in turn affects rates of local recurrence and prognosis. Therefore, it is critical that they are managed in tertiary, specialist centres with a multidisciplinary approach.


Asunto(s)
Neoplasias de Cabeza y Cuello/patología , Sarcoma/patología , Centros de Atención Terciaria/estadística & datos numéricos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Neoplasias de Cabeza y Cuello/epidemiología , Neoplasias de Cabeza y Cuello/mortalidad , Neoplasias de Cabeza y Cuello/cirugía , Humanos , Masculino , Márgenes de Escisión , Persona de Mediana Edad , Recurrencia Local de Neoplasia/epidemiología , Recurrencia Local de Neoplasia/mortalidad , Estudios Retrospectivos , Sarcoma/epidemiología , Sarcoma/mortalidad , Sarcoma/cirugía , Análisis de Supervivencia , Adulto Joven
9.
Arch Osteoporos ; 15(1): 154, 2020 10 03.
Artículo en Inglés | MEDLINE | ID: mdl-33009959

RESUMEN

The purpose was to determine if increasing serum 25(OH)D and calcium in postmenopausal women increased skeletal muscle size, strength, balance, and functional task performance while decreasing muscle fatigue. PCSA of the vastus lateralis increased and ascent of stairs time decreased after 6 months of increased serum 25(OH)D. PURPOSE: The Institute of Medicine recommends ≥ 20 ng/ml of serum 25-hydroxyvitamin D [25(OH)D] for bone and overall health. Serum 25(OH)D levels have been associated with physical performance, postural sway, and falls. The purpose of this study was to determine if increasing postmenopausal women's serum 25(OH)D levels from 20-30 ng/ml to 40-50 ng/ml improved skeletal muscle size, strength, balance, and functional performance while decreasing skeletal muscle fatigue. METHODS: Twenty-six post-menopausal women (60-85 years old) with baseline serum 25(OH)D levels between 20 and 30 ng/ml were recruited. Oral over-the-counter (OTC) vitamin D3 and calcium citrate were prescribed to increase subjects' serum 25(OH)D to levels between 40 and 50 ng/ml, serum calcium levels above 9.2 mg/dl, and PTH levels below 60 pg/ml, which were confirmed at 6 and 12 weeks. Outcome measures assessed at baseline and 6 months included muscle physiological cross-sectional area (PCSA), muscle strength, postural balance, time to perform functional tasks, and muscle fatigue. Repeated measures comparisons between baseline and follow-up were performed. RESULTS: Nineteen subjects completed the study. One individual could not afford the time commitment for the repeated measures. Three individuals did not take their vitamin D as recommended. Two subjects were lost to follow-up (lack of interest), and one did not achieve targeted serum 25(OH)D. Vastus lateralis PCSA increased (p = 0.007) and ascent of stair time decreased (p = 0.042) after 6 months of increasing serum 25(OH)D levels from 20-30 ng/ml to 40-50 ng/ml. Isometric strength was unchanged. Anterior-posterior center of pressure (COP) excursion and COP path length decreased (p < 0.1) albeit non-significantly, suggesting balance may improve from increased serum 25(OH)D and calcium citrate levels. CONCLUSIONS: Several measures of muscle structure and function were sensitive to elevated serum 25(OH)D and calcium levels indicating that further investigation of this phenomenon in post-menopausal women is warranted.


Asunto(s)
Citrato de Calcio/administración & dosificación , Calcio/sangre , Colecalciferol/administración & dosificación , Fatiga Muscular/efectos de los fármacos , Fuerza Muscular/efectos de los fármacos , Posmenopausia/sangre , Deficiencia de Vitamina D/prevención & control , Vitamina D/análogos & derivados , Absorciometría de Fotón/métodos , Anciano , Anciano de 80 o más Años , Conservadores de la Densidad Ósea/administración & dosificación , Conservadores de la Densidad Ósea/uso terapéutico , Citrato de Calcio/uso terapéutico , Colecalciferol/uso terapéutico , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Persona de Mediana Edad , Actividad Motora/efectos de los fármacos , Proyectos Piloto , Análisis y Desempeño de Tareas , Resultado del Tratamiento , Vitamina D/sangre , Deficiencia de Vitamina D/sangre , Deficiencia de Vitamina D/tratamiento farmacológico , Vitaminas/administración & dosificación , Vitaminas/uso terapéutico
10.
Zootaxa ; 4778(3): zootaxa.4778.3.1, 2020 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-33055808

RESUMEN

Chrysaora (Pèron Lesueur 1810) is the most diverse genus within Discomedusae, and 15 valid species are currently recognised, with many others not formally described. Since Chrysaora fulgida (Reynaud 1830) was first recognised as occurring off the south west (SW) coast off South Africa, the species has been variously synonymised with Chrysaora hysoscella (Linnaeus 1767) and Chrysaora africana (Vanhöffen 1902). Using DNA evidence alongside multivariate tools to analyse quantitative morphometric and meristic data, as well as information from the cnidome, we unambiguously separate C. fulgida from C. hysoscella; we resurrect C. africana as a valid species and recognise a new species, Chrysaora agulhensis sp. nov. Full descriptions of C. fulgida, C. africana and C. agulhensis sp. nov. are provided. The species have different geographical patterns of distribution around the region, with restricted areas of overlap: C. agulhensis sp. nov. is found along the southern coast of South Africa and over the Agulhas Bank, C. fulgida extends from Cape Point in South Africa to southern Angola, and C. africana can be found from southern Namibia northwards to the Gulf of Guinea. The species can be readily separated in the field by a combination of tentacle/lappet number and shape, colour patterns and the form of the oral arms.


Asunto(s)
Ecosistema , Escifozoos , Animales
12.
J Fish Biol ; 92(3): 752-772, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29537083

RESUMEN

The oceans of the world are slowly losing oxygen, in part because of climate change and in part because of anthropogenic eutrophication. This deoxygenation affects marine organisms in species-specific ways. This paper reviews what is known on how hypoxia tolerant species respond to low dissolved oxygen, using the bearded goby Sufflogobius bibarbatus as a model system. This species is endemic to the Benguela upwelling ecosystem, where, off Namibia, 9000 km2 of the shelf is hypoxic. Here, the species is now considered central to ecosystem functioning and in recent decades it has sustained commercial fisheries. Unlike their predators, S. bibarbatus has strong anti-predator responses as they can remain alert and escape threats in anoxic and severely hypoxic waters and can cope with sulphide shocks. Populations display diel vertical migration and shuttle between suboxic seabed refugia during the day to more oxygenated waters higher up in the water column at night and whilst they may share the water column with predators they may reduce their predation risk by associating with jellyfish (Aequorea forskalea and Chrysaora fulgida). The spatial distribution of S. bibarbatus varies with changes in available oxygen and populations expand and contract with climate-induced changes in the distribution of hypoxic waters. This species has an unusual diet and plays an important role in ecosystem functioning. It is a batch-spawner, with a protracted spawning season. Remarkably, males display alternative reproductive tactics and reproduction can take place at oxygen levels <0·5 ml l-1 dissolved oxygen on the shelf break. Gaps in knowledge are identified and future works are proposed.


Asunto(s)
Aclimatación , Adaptación Fisiológica , Hipoxia , Perciformes/fisiología , Migración Animal , Animales , Cambio Climático , Ecosistema , Femenino , Masculino , Namibia , Océanos y Mares , Oxígeno/análisis , Conducta Predatoria , Reproducción/fisiología , Estaciones del Año , Agua de Mar/química
13.
J Gen Intern Med ; 32(Suppl 1): 65-69, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28271434

RESUMEN

In 2016, the Veterans Health Administration (VHA) held a Weight Management State of the Art conference to identify evidence gaps and develop a research agenda for population-based weight management for veterans. Included were behavioral, pharmacologic, and bariatric surgery workgroups. This article summarizes the bariatric surgery workgroup (BSWG) findings and recommendations for future research. The BSWG agreed that there is evidence from randomized trials and large observational studies suggesting that bariatric surgery is superior to medical therapy for short- and intermediate-term remission of type 2 diabetes, long-term weight loss, and long-term survival. Priority evidence gaps include long-term comorbidity remission, mental health, substance abuse, and health care costs. Evidence of the role of endoscopic weight loss options is also lacking. The BSWG also noted the limited evidence regarding optimal timing for bariatric surgery referral, barriers to bariatric surgery itself, and management of high-risk bariatric surgery patients. Clinical trials of pre- and post-surgery interventions may help to optimize patient outcomes. A registry of overweight and obese veterans and a workforce assessment to determine the VHA's capacity to increase bariatric surgery access were recommended. These will help inform policy modifications and focus the research agenda to improve the ability of the VHA to deliver population-based weight management.


Asunto(s)
Cirugía Bariátrica/métodos , Investigación sobre Servicios de Salud/métodos , Obesidad Mórbida/cirugía , Comorbilidad , Humanos , Manejo de la Obesidad/métodos , Obesidad Mórbida/complicaciones , Estados Unidos , United States Department of Veterans Affairs , Salud de los Veteranos , Pérdida de Peso
15.
J Microsc ; 264(3): 304-310, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-27513447

RESUMEN

The mechanism of the increase in ductility in bulk metallic glass matrix composites over monolithic bulk metallic glasses is to date little understood, primarily because the interplay between dislocations in the crystalline phase and shear bands in the glass could neither be imaged nor modelled in a validated way. To overcome this roadblock, we show that shear bands can be imaged in three dimensions by atom probe tomography from density variations in the reconstructed atomic density, which density-functional theory suggests being a local-work function effect. Imaging of near-interface shear bands in Ti48 Zr20 V12 Cu5 Be15 bulk metallic glass matrix composite permits measurement of their composition, thickness, branching and interactions with the dendrite interface. These results confirm that shear bands here nucleate from stress concentrations in the glass due to intense, localized plastic deformation in the dendrites rather than intrinsic structural inhomogeneities.

16.
ANS Adv Nurs Sci ; 38(4): 347-54, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26517343

RESUMEN

Dr Joyce H. Clifford was world renowned for her excellence in nursing administration and leadership. The purpose of this article is to examine her complete body of published scholarship and analyze her papers as a method of understanding her intellectual progression as a leader in the discipline, as well as to document how her conceptualization of professional practice and the practice environment advanced nursing practice and patient and family care. Using the qualitative method of narrative inquiry, a systematic analysis of her papers was conducted to describe the evolution of her scholarship and her impact on the discipline and patient care. We reviewed all known existing papers, categorized them into 3 stages, and discuss them here. Using quotes from her work, we have added her voice to the compelling professional practice issues she addressed in her lifetime.


Asunto(s)
Liderazgo , Enfermeras Administradoras/historia , Atención de Enfermería/psicología , Femenino , Historia de la Enfermería , Historia del Siglo XX , Historia del Siglo XXI , Humanos , Estados Unidos
17.
Ann Neurol ; 78(6): 982-994, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26418456

RESUMEN

OBJECTIVE: Mutations in TPM3, encoding Tpm3.12, cause a clinically and histopathologically diverse group of myopathies characterized by muscle weakness. We report two patients with novel de novo Tpm3.12 single glutamic acid deletions at positions ΔE218 and ΔE224, resulting in a significant hypercontractile phenotype with congenital muscle stiffness, rather than weakness, and respiratory failure in one patient. METHODS: The effect of the Tpm3.12 deletions on the contractile properties in dissected patient myofibers was measured. We used quantitative in vitro motility assay to measure Ca(2+) sensitivity of thin filaments reconstituted with recombinant Tpm3.12 ΔE218 and ΔE224. RESULTS: Contractility studies on permeabilized myofibers demonstrated reduced maximal active tension from both patients with increased Ca(2+) sensitivity and altered cross-bridge cycling kinetics in ΔE224 fibers. In vitro motility studies showed a two-fold increase in Ca(2+) sensitivity of the fraction of filaments motile and the filament sliding velocity concentrations for both mutations. INTERPRETATION: These data indicate that Tpm3.12 deletions ΔE218 and ΔE224 result in increased Ca(2+) sensitivity of the troponin-tropomyosin complex, resulting in abnormally active interaction of the actin and myosin complex. Both mutations are located in the charged motifs of the actin-binding residues of tropomyosin 3, thus disrupting the electrostatic interactions that facilitate accurate tropomyosin binding with actin necessary to prevent the on-state. The mutations destabilize the off-state and result in excessively sensitized excitation-contraction coupling of the contractile apparatus. This work expands the phenotypic spectrum of TPM3-related disease and provides insights into the pathophysiological mechanisms of the actin-tropomyosin complex.


Asunto(s)
Contracción Muscular , Fibras Musculares Esqueléticas/patología , Enfermedades Musculares/genética , Tropomiosina/genética , Preescolar , Exoma , Femenino , Humanos , Masculino , Enfermedades Musculares/patología , Enfermedades Musculares/fisiopatología , Mutación , Fenotipo , Insuficiencia Respiratoria , Eliminación de Secuencia
18.
Int J Stroke ; 10(8): 1187-91, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26311530

RESUMEN

BACKGROUND: We sought to investigate the frequency of microbleed development following intracerebral hemorrhage in a predominantly African-American population and to identify predictors of new microbleed formation. AIMS AND/OR HYPOTHESIS: To investigate the frequency and predictors of new microbleeds following intracerebral hemorrhage. METHODS: The DECIPHER study was a prospective, longitudinal, magnetic resonance-based cohort study designed to evaluate racial/ethnic differences in risk factors for microbleeds and to evaluate the prognostic impact of microbleeds in this intracerebral hemorrhage population. We evaluated new microbleed formation in two time periods: from baseline to 30 days and from 30 days to year 1. RESULTS: Of 200 subjects enrolled in DECIPHER, 84 had magnetic resonance imaging at all required time points to meet criteria for this analysis. In the baseline to day 30 analysis, 11 (13·1%) had new microbleeds, compared with 25 (29·8%) in the day 30 to year 1 analysis. Logistic regression analysis demonstrated that baseline number of microbleeds [odds ratio 1·05 (95% confidence interval 1·01, 1·08), P = 0·01] was associated with new microbleed formation at 30 days. A logistic regression model predicting new microbleed at one-year included baseline number of microbleeds [odds ratio 1·05 (1·00, 1·11), P = 0·046], baseline age [odds ratio 1·05 (1·00, 1·10), P = 0·04], and white matter disease score [odds ratio 1·18 (0·96, 1·45). P = 0·115]. Overall, 28 of 84 (33·3%) intracerebral hemorrhage subjects formed new microbleeds at some point in the first year post-intracerebral hemorrhage. CONCLUSIONS: We found that one-third of intracerebral hemorrhage subjects in this cohort surviving one-year developed new microbleeds, which suggests a dynamic and rapidly progressive vasculopathy. Future studies are needed to examine the impact of new microbleed formation on patient outcomes.


Asunto(s)
Hemorragias Intracraneales/etiología , Accidente Cerebrovascular/complicaciones , Encéfalo/patología , Femenino , Humanos , Hemorragias Intracraneales/diagnóstico , Hemorragias Intracraneales/etnología , Hemorragias Intracraneales/patología , Modelos Logísticos , Estudios Longitudinales , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Análisis Multivariante , Pronóstico , Estudios Prospectivos , Factores de Riesgo , Accidente Cerebrovascular/diagnóstico , Accidente Cerebrovascular/etnología , Accidente Cerebrovascular/patología , Factores de Tiempo , Estados Unidos/epidemiología
19.
Bone Joint J ; 97-B(6): 853-61, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26033069

RESUMEN

Vascularised fibular grafts (VFGs ) are a valuable surgical technique in limb salvage after resection of a tumour. The primary objective of this multicentre study was to assess the risk factors for failure and complications for using a VFG after resection of a tumour. The study involved 74 consecutive patients (45 men and 29 women with mean age of 23 years (1 to 64) from four tertiary centres for orthopaedic oncology who underwent reconstruction using a VFG after resection of a tumour between 1996 and 2011. There were 52 primary and 22 secondary reconstructions. The mean follow-up was 77 months (10 to 195). In all, 69 patients (93%) had successful limb salvage; all of these united and 65 (88%) showed hypertrophy of the graft. The mean time to union differed between those involving the upper (28 weeks; 12 to 96) and lower limbs (44 weeks; 12 to 250). Fracture occurred in 11 (15%), and nonunion in 14 (19%) patients. In 35 patients (47%) at least one complication arose, with a greater proportion in lower limb reconstructions, non-bridging osteosynthesis, and in children. These complications resulted in revision surgery in 26 patients (35%). VFG is a successful and durable technique for reconstruction of a defect in bone after resection of a tumour, but is accompanied by a significant risk of complications, that often require revision surgery. Union was not markedly influenced by the need for chemo- or radiotherapy, but should not be expected during chemotherapy. Therefore, restricted weight-bearing within this period is advocated.


Asunto(s)
Neoplasias Óseas/cirugía , Peroné/trasplante , Osteosarcoma/cirugía , Sarcoma de Ewing/cirugía , Adolescente , Adulto , Niño , Preescolar , Femenino , Humanos , Lactante , Recién Nacido , Recuperación del Miembro , Masculino , Persona de Mediana Edad , Procedimientos de Cirugía Plástica , Soporte de Peso , Adulto Joven
20.
J Evol Biol ; 28(6): 1185-202, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25882679

RESUMEN

Although possession is 'nine-tenths of the law', respect for ownership is widespread in the animal kingdom even without third-party enforcement. Thus, the first individuals to find objects are frequently left unchallenged by potential competitors and tend to win contests when disputes arise. Game theory has shown that respect for ownership ('Bourgeois' behaviour) can arise as an arbitrary convention to avoid costly disputes. However, the same theory predicts that a paradoxical respect for lack of ownership ('anti-Bourgeois' behaviour) can evolve under the same conditions and in some cases is the only stable outcome. Despite these predictions, anti-Bourgeois behaviour is rare in nature, whereas respect for ownership is frequently not absolute. Here, we review extensions of the classic models involving repeated interactions, confusion over roles, strategic coordination of behaviour ('secret handshakes'), owner-intruder asymmetries and continuous control of fighting investment. Confusion over roles and owner-intruder asymmetries in fighting ability may explain why respect for ownership is often partial. Moreover, although most model extensions facilitate the evolution of Bourgeois-like behaviour, secret handshakes and continuous control of fighting investment render the alternative anti-Bourgeois convention unstable. We develop these insights to highlight several key areas for future investigation.


Asunto(s)
Evolución Biológica , Propiedad , Animales , Conducta Competitiva , Humanos , Territorialidad
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