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1.
J Anim Ecol ; 2024 Jun 16.
Artículo en Inglés | MEDLINE | ID: mdl-38881237

RESUMEN

During animal migration, ephemeral communities of taxa at all trophic levels co-occur over space and time. The interactions between predators and prey along migration corridors are ecologically and evolutionarily significant. However, these interactions remain understudied in terrestrial systems and warrant further investigations using novel approaches. We investigated the predator-prey interactions between a migrating avivorous predator and ephemeral avian prey community in the fall migration season. We tested for associations between avian traits and prey selection and hypothesized that prey traits (i.e. relative size, flocking behaviour, habitat, migration tendency and availability) would influence prey selection by a sexually dimorphic raptor on migration. To document prey consumption, we sampled trace prey DNA from beaks and talons of migrating sharp-shinned hawks Accipiter striatus (n = 588). We determined prey availability in the ephemeral avian community by extracting weekly abundance indices from eBird Status and Trends data. We used discrete choice models to assess prey selection and visualized the frequency of prey in diet and availability on the landscape over the fall migration season. Using eDNA metabarcoding, we detected prey species on 94.1% of the hawks sampled (n = 525/588) comprising 1396 prey species detections from 65 prey species. Prey frequency in diet and eBird relative abundance of prey species were correlated over the migration season for top-selected prey species, suggesting prey availability is an important component of raptor-songbird interactions during fall. Prey size, flocking behaviour and non-breeding habitat association were prey traits that significantly influenced predator choice. We found differences between female and male hawk prey selection, suggesting that sexual size dimorphism has led to distinct foraging strategies on migration. This research integrated field data collected by a volunteer-powered raptor migration monitoring station and public-generated data from eBird to reveal elusive predator-prey dynamics occurring in an ephemeral raptor-songbird community during fall migration. Understanding dynamic raptor-songbird interactions along migration routes remains a relatively unexplored frontier in animal ecology and is necessary for the conservation and management efforts of migratory and resident communities.


Durante la migración animal, las comunidades efímeras de taxones de todos los niveles tróficos coexisten en el espacio y el tiempo. Las interacciones entre depredadores y presas a lo largo de los corredores migratorios son significativas desde el punto de vista ecológica y evolutivo. Sin embargo, estas interacciones siguen siendo poco estudiadas en los sistemas terrestres y justifican más investigaciones utilizando enfoques novedosos. Investigamos las interacciones depredador­presa entre un depredador avívoro migratorio y una comunidad de presas aviares efímeras en la temporada migratoria otoñal. Probamos las asociaciones entre los rasgos de las aves y la selección de presas y planteamos la hipótesis de que los rasgos de las presas (tamaño relativo, comportamiento de bandada, hábitat, tendencia migratoria y disponibilidad) influirían en la selección de presas por parte de una rapaz sexualmente dimórfica durante la migración. Para documentar el consumo de presas, recogimos rastros de ADN de presas de picos y garras de Gavilán Americano Accipiter striatus (n = 588) migratorios. Determinamos la disponibilidad de presas en la comunidad de aves efímeras extrayendo índices de abundancia semanales de los datos de eBird Estado y Tendencias. Utilizamos modelos de elección discreta para evaluar la selección de presas y visualizamos la frecuencia de las presas en la dieta y la disponibilidad en el paisaje durante la temporada migratoria otoñal. Utilizando el metacódigo de barras del ADN ambiental, detectamos especies de presas en el 94,1% de los halcones muestreados (n = 525/588), comprendiendo 1396 detecciones de 65 especies de presas. La frecuencia de presas en la dieta y la abundancia relativa de especies de presas en eBird se correlacionaron a lo largo de la temporada de migración para las principales especies de presas seleccionadas, lo que sugiere que la disponibilidad de presas es un componente importante de las interacciones entre aves rapaces y aves canoras durante el otoño. El tamaño de las presas, el comportamiento de las bandadas y la asociación con el hábitat no reproductivo fueron rasgos de presa que influyeron significativamente en la elección de los depredadores. Encontramos diferencias entre la selección de presas de gavilán hembra y macho, lo que sugiere que el dimorfismo sexual de tamaño ha conducido a distintas estrategias de alimentación durante la migración. Esta investigación integró datos de campo recopilados por una estación de monitoreo de migración de rapaces impulsada por voluntarios y datos generados públicamente por eBird para revelar la esquiva dinámica depredador­presa que ocurre en una comunidad efímera de rapaces y aves canoras durante la migración otoñal. Comprender las interacciones dinámicas entre rapaces y aves canoras a lo largo de las rutas migratorias sigue siendo una frontera relativamente inexplorada en la ecología animal y es necesaria para los esfuerzos de conservación y gestión de las comunidades migratorias y residentes.

2.
HPB (Oxford) ; 23(11): 1656-1665, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34544628

RESUMEN

INTRODUCTION: The SARS-CoV-2 pandemic presented healthcare providers with an extreme challenge to provide cancer services. The impact upon the diagnostic and treatment capacity to treat pancreatic cancer is unclear. This study aimed to identify national variation in treatment pathways during the pandemic. METHODS: A survey was distributed to all United Kingdom pancreatic specialist centres, to assess diagnostic, therapeutic and interventional services availability, and alterations in treatment pathways. A repeating methodology enabled assessment over time as the pandemic evolved. RESULTS: Responses were received from all 29 centres. Over the first six weeks of the pandemic, less than a quarter of centres had normal availability of diagnostic pathways and a fifth of centres had no capacity whatsoever to undertake surgery. As the pandemic progressed services have gradually improved though most centres remain constrained to some degree. One third of centres changed their standard resectable pathway from surgery-first to neoadjuvant chemotherapy. Elderly patients, and those with COPD were less likely to be offered treatment during the pandemic. CONCLUSION: The COVID-19 pandemic has affected the capacity of the NHS to provide diagnostic and staging investigations for pancreatic cancer. The impact of revised treatment pathways has yet to be realised.


Asunto(s)
COVID-19 , Neoplasias Pancreáticas , Anciano , Humanos , Neoplasias Pancreáticas/epidemiología , Neoplasias Pancreáticas/terapia , Pandemias , SARS-CoV-2 , Reino Unido/epidemiología
3.
J Exp Biol ; 222(Pt 12)2019 06 24.
Artículo en Inglés | MEDLINE | ID: mdl-31171604

RESUMEN

Resident birds in temperate zones respond to seasonally fluctuating temperatures by adjusting their physiology, such as changes in basal metabolic rate or peak metabolic rate during cold exposure, or altering their organ sizes, so as to match the thermogenic requirements of their current environment. Climate change is predicted to cause increases in the frequency of heat and cold wave events, which could increase the likelihood that birds will face an environmental mismatch. Here, we examined seasonality and the effects of acute and chronic heat shock to 33°C and subsequent recovery from heat shock on the ultrastructure of the superficial pectoralis muscle fiber diameter, myonuclear domain (MND) and capillary density in two temperate bird species of differing body mass, the black-capped chickadee (Poecile atricapillus) and the rock pigeon (Columba livia). We found that muscle fiber ultrastructure did not change with heat treatment. However, in black-capped chickadees, there was a significant increase in fiber diameter in spring phenotype birds compared with summer phenotype birds. In rock pigeons, we saw no differences in fiber diameter across seasons. Capillary density did not change as a function of fiber diameter in black-capped chickadees, but did change seasonally, as did MND. Across seasons, as fiber diameter decreased, capillary density increased in the pectoralis muscle of rock pigeons. For both species in this study, we found that as fiber diameter increased, so did MND. Our findings imply that these two temperate birds employ different muscular growth strategies that may be metabolically beneficial to each.


Asunto(s)
Aclimatación , Columbidae/fisiología , Músculos Pectorales/fisiología , Pájaros Cantores/fisiología , Animales , Calor , Músculos Pectorales/ultraestructura , Distribución Aleatoria
4.
J Zoo Wildl Med ; 49(1): 108-115, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29517435

RESUMEN

Chlamydiaceae bacteria infect many vertebrate hosts, and previous reports based on polymerase chain reaction (PCR) assays and serologic assays that are prone to cross-reaction among chlamydial organisms have been used to describe the prevalence of either DNA fragments or antibodies to Chlamydia spp. in wild raptorial populations. This study reports the PCR-based prevalence of Chlamydiaceae DNA that does not 100% match any avian or mammalian Chlamydiaceae in wild populations of hawks in California Buteo species. In this study, multimucosal swab samples ( n = 291) for quantitative PCR (qPCR) and plasma ( n = 78) for serology were collected from wild hawks. All available plasma samples were negative for antibodies using a C. psittaci-specific elementary body agglutination test (EBA; n = 78). For IgY antibodies all 51 available samples were negative using the indirect immunofluorescent assay. The overall prevalence of Chlamydiaceae DNA detection in wild Buteo species sampled was 1.37% (4/291) via qPCR-based analysis. Two fledgling Swainson's hawks ( Buteo swainsoni) and two juvenile red-tailed hawks ( Buteo jamaicensis) were positive by qPCR-based assay for an atypical chlamydial sequence that did not 100% match any known C. psittaci genotype. Positive swab samples from these four birds were sequenced based on the ompA gene and compared by high-resolution melt analysis with all known avian and mammalian Chlamydiaceae. The amplicon sequence did not 100% match any known avian chlamydial sequence; however, it was most similar (98.6%) to C. psittaci M56, a genotype that is typically found in muskrats and hares. Culture and full genome sequence analysis of Chlamydia spp. isolated from diseased hawks will be necessary to classify this organism and to better understand its epizootiology and potential health impact on wild Buteo populations in California.


Asunto(s)
Enfermedades de las Aves/microbiología , Infecciones por Chlamydiaceae/veterinaria , Chlamydiaceae/aislamiento & purificación , Halcones/microbiología , Animales , Enfermedades de las Aves/epidemiología , California/epidemiología , Infecciones por Chlamydiaceae/epidemiología , Infecciones por Chlamydiaceae/microbiología , Estudios Seroepidemiológicos
5.
Dig Surg ; 34(1): 36-42, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-27384180

RESUMEN

BACKGROUND: Differentiating hepatic mucinous cystic neoplasms (MCNs) from simple hepatic cysts (SCs) preoperatively is a challenging task. Our aim was to determine whether radiological features on ultrasound scan (USS), CT or MRI, cyst fluid tumour markers, or multidisciplinary team (MDT) outcomes could differentiate MCN from SC. METHODS: A retrospective review of radiological features, cyst fluid tumour marker levels and MDT outcomes in 52 patients was performed. RESULTS: There were 13 patients with MCN, 38 with SC and one ciliated foregut cyst. MCNs were more often solitary (p = 0.006). Although no other individual radiological characteristic on USS, CT or MRI was predictive of MCN, MDT outcomes stating that a cyst was complex in nature were highly predictive (p = 0.0007). Cyst fluid carbohydrate antigen 19-9, carcino-embryonic antigen and cancer antigen 125 were unable to differentiate MCN from SC (p = 0.45, p = 0.49, and p = 0.73, respectively). CONCLUSIONS: MDT outcomes are of greatest value when trying to differentiate MCN from SC, as well as having a solitary cyst on imaging. Conventional cyst fluid tumour markers are unhelpful. All suspicious cystic liver lesions should be discussed pre-operatively by a hepatobiliary MDT to determine the most appropriate surgical approach.


Asunto(s)
Quistes/química , Quistes/diagnóstico por imagen , Neoplasias Hepáticas/diagnóstico por imagen , Neoplasias Quísticas, Mucinosas y Serosas/diagnóstico por imagen , Grupo de Atención al Paciente , Adulto , Anciano , Anciano de 80 o más Años , Antígeno Ca-125/análisis , Antígeno CA-19-9/análisis , Diagnóstico Diferencial , Femenino , Humanos , Neoplasias Hepáticas/cirugía , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Neoplasias Quísticas, Mucinosas y Serosas/cirugía , Estudios Retrospectivos , Tomografía Computarizada por Rayos X , Ultrasonografía , Adulto Joven
6.
BMC Surg ; 17(1): 23, 2017 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-28270136

RESUMEN

BACKGROUND: Centralisation of specialist surgical services requires that patients are referred to a regional centre for surgery. This process may disadvantage patients who live far from the regional centre or are referred from other hospitals by making referral less likely and by delaying treatment, thereby allowing tumour progression. The aim of this study is to explore the outcome of surgery for peri-ampullary cancer (PC) with respect to referring hospital and travel distance for treatment within a network served by five hospitals. METHODS: Review of a unit database was undertaken of patients undergoing surgery for PC between January 2006 and May 2014. RESULTS: 394 patients were studied. Although both the median travel distance for patients from the five hospitals (10.8, 86, 78.8, 54.7 and 89.2 km) (p < 0.05), and the annual operation rate for PC (2.99, 3.29, 2.13, 3.32 and 3.07 per 100,000) (p = 0.044) were significantly different, no correlation was noted between patient travel distance and population operation rate at each hospital. No difference was noted between patients from each hospital in terms of resection completion rate or pathological stage of the resected tumours. The median survival after diagnosis for patients referred from different hospitals ranged from 1.2 to 1.7 years and regression analysis revealed that increased travel distance to the regional centre was associated with a small survival advantage. CONCLUSION: Although variation in the provision and outcome of surgery for PC between regional hospitals is noted, this is not adversely affected by geographical isolation from the regional centre. TRIAL REGISTRATION: This study is part of post-graduate research degree project. The study is registered with ClinicalTrials.gov (unique identifier NCT02296736 ) November 18, 2014.


Asunto(s)
Adenocarcinoma/mortalidad , Adenocarcinoma/cirugía , Neoplasias del Sistema Digestivo/mortalidad , Neoplasias del Sistema Digestivo/cirugía , Adulto , Anciano , Anciano de 80 o más Años , Ampolla Hepatopancreática/cirugía , Neoplasias del Conducto Colédoco/mortalidad , Neoplasias del Conducto Colédoco/cirugía , Bases de Datos Factuales , Neoplasias Duodenales/mortalidad , Neoplasias Duodenales/cirugía , Femenino , Accesibilidad a los Servicios de Salud/estadística & datos numéricos , Hospitales Especializados/estadística & datos numéricos , Humanos , Masculino , Persona de Mediana Edad , Neoplasias Pancreáticas/mortalidad , Neoplasias Pancreáticas/cirugía , Derivación y Consulta , Análisis de Supervivencia , Resultado del Tratamiento , Reino Unido/epidemiología
7.
Forensic Sci Med Pathol ; 13(3): 317-327, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28526950

RESUMEN

The purpose of this study was to investigate the impact of post-mortem computed-tomography angiography (PMCTA) on the histology of the liver, kidneys and heart. Multiple tissue cores were collected from the liver, left and right kidneys and left ventricle utilizing CT-guided biopsy. Subsequent whole body PMCTA was performed using a solution of polyethylene glycol and iodinated radiographic contrast, and an embalming pump. Corresponding biopsy cores were collected at autopsy, and blinded histology analysis assessing for PMCTA-induced histology artefact was performed. The blinded analysis of pre-PMCTA and post-PMCTA biopsy samples demonstrated that whole body PMCTA had no effect on the histological analyses of the liver (0%, CI = 0-13.7%), left ventricle of the heart (0%, CI = 0-36.9%) and right kidney (0%, CI = 13.2%), however likely caused increased Bowman's capsule spaces in the left kidney of one case (4%, CI = 0.01-20.4%). Other artefactual histological changes identified included eosinophilic material in the liver, whiter interstitium and dilated tubules in kidney samples, and autolysis-related changes, however these could not be categorically attributed to the PMCTA procedure. PMCTA causes zero or minimal effect to the histological examination of the liver, left kidney, right kidney and left ventricle, and as such performing PMCTA prior to autopsy is unlikely to impact autopsy histological results in these organs.


Asunto(s)
Angiografía por Tomografía Computarizada , Medios de Contraste , Ventrículos Cardíacos/patología , Biopsia Guiada por Imagen , Riñón/patología , Hígado/patología , Adulto , Anciano , Anciano de 80 o más Años , Autopsia/métodos , Biopsia con Aguja Gruesa , Femenino , Patologia Forense , Humanos , Yopamidol , Masculino , Persona de Mediana Edad , Imagen de Cuerpo Entero , Adulto Joven
8.
HPB (Oxford) ; 18(4): 354-9, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-27037205

RESUMEN

BACKGROUND: Delay between diagnosis of peri-ampullary cancer (PC) and surgery may allow tumour progression and affect outcome. The aim of this study was to explore associations of interval to surgery (IS) with pathological outcomes and survival in patients with PC. METHOD: A database review of all patients undergoing surgery between 2006 and 2014 was undertaken. IS was measured from diagnosis by imaging. Potential association between IS and survival was measured using Cox regression analysis, and between IS and pathological outcome with multivariate logistic analysis. RESULTS: 388 patients underwent surgery. The median IS was 49 days (1-551 days), and was not associated with any of the evaluated outcomes in patients with pancreatic (149) or distal bile duct (46) cancer. For patients with ampullary cancer (71) longer IS was associated with improved survival, with median survival of 27.5 months for patients waiting ≤ median IS (35) and 38.3 months for patients waiting > median IS (36) for surgery (p = 0.041). A higher rate of margin positivity (31.4%) was also noted among patients who waited less than the median IS compared to those waiting longer than this interval (11.4%) (p = 0.032). CONCLUSION: For patients with ampullary cancer there is a paradoxical improvement in outcome among those with a longer IS, which may be explained by progression to inoperability of more aggressive lesions.


Asunto(s)
Adenocarcinoma/cirugía , Ampolla Hepatopancreática/cirugía , Neoplasias de los Conductos Biliares/cirugía , Neoplasias Duodenales/cirugía , Neoplasias Pancreáticas/cirugía , Tiempo de Tratamiento , Adenocarcinoma/mortalidad , Adenocarcinoma/patología , Adulto , Anciano , Anciano de 80 o más Años , Ampolla Hepatopancreática/patología , Neoplasias de los Conductos Biliares/mortalidad , Neoplasias de los Conductos Biliares/patología , Distribución de Chi-Cuadrado , Bases de Datos Factuales , Neoplasias Duodenales/mortalidad , Neoplasias Duodenales/patología , Femenino , Humanos , Estimación de Kaplan-Meier , Modelos Logísticos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Neoplasia Residual , Oportunidad Relativa , Neoplasias Pancreáticas/mortalidad , Neoplasias Pancreáticas/patología , Modelos de Riesgos Proporcionales , Factores de Riesgo , Factores de Tiempo , Resultado del Tratamiento
9.
HPB (Oxford) ; 18(7): 586-92, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-27346139

RESUMEN

BACKGROUND: A period of recovery is commonly allowed between completion of chemotherapy for colorectal liver metastases (CRLM) and resection, during which tumour progression may occur. The study-aim is to assess the growth of CRLM in this interval and association with outcome. METHOD: Data on 146 patients were analysed. Change in tumour size was assessed by comparing size determined by imaging performed on completion of chemotherapy with that determined by examination of the resected specimen, categorised by RECIST criteria. RESULTS: In the interval before surgery sixteen patients (11%) fulfilled criteria for partial response (PR), 48 (33%) had stable disease (SD) and 82 (56%) had progressive disease (PD). Among patients with PD following chemotherapy the median disease-free survival of patients who initially responded (26 months) was longer than in those who initially had stable disease (7 months) (P = 0.002). No association was noted between rate of tumour growth after completion of chemotherapy and disease-free survival. CONCLUSION: Change in tumour size after completion of chemotherapy is variable and can be rapid, especially in patients who initially respond to treatment. However, disease-free survival is determined by tumour behaviour during treatment and not by change in size after completion of chemotherapy.


Asunto(s)
Neoplasias Colorrectales/patología , Hepatectomía , Neoplasias Hepáticas/secundario , Neoplasias Hepáticas/terapia , Terapia Neoadyuvante , Adulto , Anciano , Anciano de 80 o más Años , Quimioterapia Adyuvante , Neoplasias Colorrectales/mortalidad , Bases de Datos Factuales , Progresión de la Enfermedad , Supervivencia sin Enfermedad , Femenino , Hepatectomía/efectos adversos , Hepatectomía/mortalidad , Humanos , Estimación de Kaplan-Meier , Neoplasias Hepáticas/diagnóstico por imagen , Neoplasias Hepáticas/mortalidad , Masculino , Persona de Mediana Edad , Terapia Neoadyuvante/efectos adversos , Terapia Neoadyuvante/mortalidad , Factores de Riesgo , Factores de Tiempo , Tomografía Computarizada por Rayos X , Resultado del Tratamiento , Carga Tumoral
10.
J Surg Res ; 198(1): 87-92, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26095422

RESUMEN

BACKGROUND: Liver resection is associated with significant morbidity, and assessment of risk is an important part of preoperative consultations. Objective methods exist to assess operative risk, including cardiopulmonary exercise testing (CPX). Subjective assessment is also made in clinic, and patients perceived to be high-risk are referred for CPX at our institution. This article addresses clinicians' ability to identify patients with a higher risk of surgical complications after hepatectomy, using selection for CPX as a surrogate marker for increased operative risk. MATERIALS AND METHODS: Prospectively collected data on patients undergoing hepatectomy between February 2008 and November 2013 were retrieved and the cohort divided according to CPX referral. Complications were classified using the Clavien-Dindo system. RESULTS: CPX testing was carried out before 101 of 405 liver resections during the study period. The median age was 72 and 64 in CPX and non-CPX groups, respectively (P < 0.001). The resection size was similar between the groups. No difference was noted for grade III complications between CPX and non-CPX tested-groups; however, 19 (18.8%) and 28 (9.2%) patients suffered grade IV-V complications, respectively (P = 0.009). There was no difference in long-term survival between groups (P = 0.63). CONCLUSIONS: This study attempts to assess clinicians' ability to identify patients at greater risk of complications after hepatectomy. The confirmation that patients identified in this way are at greater risk of grade IV-V complications demonstrates the value of preoperative counseling. High-risk patients do not have worse long-term outcomes suggesting survival is determined by other factors, particularly disease recurrence.


Asunto(s)
Prueba de Esfuerzo , Hepatectomía/efectos adversos , Cuidados Preoperatorios , Medición de Riesgo , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos
11.
Eur Spine J ; 24(10): 2321-9, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25862653

RESUMEN

PURPOSE: Despite being commonly affected by degenerative disorders, there are few data on normal thoracic intervertebral disc dimensions. A morphometric analysis of adult thoracic intervertebral discs was, therefore, undertaken. METHODS: Archival computed tomography scans of 128 recently deceased individuals (70 males, 58 females, 20-79 years) with no known spinal pathology were analysed to determine thoracic disc morphometry and variations with disc level, sex and age. Reliability was assessed by intraclass correlation coefficients (ICCs). RESULTS: Anterior and posterior intervertebral disc heights and axial dimensions were significantly greater in men (anterior disc height 4.0±1.4 vs 3.6±1.3 mm; posterior disc height 3.6±0.90 vs 3.4±0.93 mm; p<0.01). Disc heights and axial dimensions at T4-5 were similar or smaller than at T2-3, but thereafter increased caudally (mean anterior disc height T4-5 and T10-11, 2.7±0.7 and 5.4±1.2 mm, respectively, in men; 2.6±0.8 and 5.1±1.3 mm, respectively, in women; p<0.05). Except at T2-3, anterior disc height decreased with advancing age and anteroposterior and transverse disc dimensions increased; posterior and middle disc heights and indices of disc shape showed no consistent statistically significant changes. Most parameters showed substantial to almost perfect agreement for intra- and inter-rater reliability. CONCLUSIONS: Thoracic disc morphometry varies significantly and consistently with disc level, sex and age. This study provides unique reference data on adult thoracic intervertebral disc morphometry, which may be useful when interpreting pathological changes and for future biomechanical and functional studies.


Asunto(s)
Disco Intervertebral/diagnóstico por imagen , Vértebras Torácicas/diagnóstico por imagen , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estándares de Referencia , Tomografía Computarizada por Rayos X , Adulto Joven
12.
Forensic Sci Med Pathol ; 11(2): 177-85, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25711290

RESUMEN

PURPOSE: Recognition of injury to the hyoid bone is intrinsic to post-mortem examination. Given its superficial location in the neck hyoid fractures are generally associated with some form of compressive neck force although they are well recognized in the peri-mortem period, in the context of manual handling and resuscitation. Hyoid fractures are variably reported to occur in manual strangulation and during hanging. METHODS: In this study Computer Tomography (CT) scans of the head and neck of 431 deceased persons (235 males and 196 females) between the ages of 1 day and 100 years of age (mean age 35.93 ± 24.15) and including 25 victims of hangings were examined to reveal the pattern of age-related change and the types of injury that occurred. Hyoid variants were also documented. RESULTS: The synchondroses between greater cornua and body were found to progressively fuse with age although in the current sample 20% non-fusion was observed beyond 65 years of age. Sex differences were evident in adult hyoid bones and discriminant function analysis correctly confirmed sex in 74.7% of cases. CONCLUSIONS: The greatest age-related changes occurred from puberty to post-adolescence and a linear regression equation successfully assessed age into three general categories in 87.7% of cases. Hyoid fractures were documented in 24% of victims of hangings and while previous reports indicate these are more likely in older age, when synchondroses are fused, in this study the average age of victims with fracture was 27 ± 10 years. In the majority of cases the site of ligature was below the hyoid bone and in only one on the hyoid body.


Asunto(s)
Hueso Hioides/diagnóstico por imagen , Tomografía Computarizada Multidetector , Adolescente , Adulto , Determinación de la Edad por el Esqueleto , Anciano , Anciano de 80 o más Años , Envejecimiento , Niño , Preescolar , Análisis Discriminante , Femenino , Antropología Forense , Fracturas Óseas/diagnóstico por imagen , Humanos , Hueso Hioides/anatomía & histología , Hueso Hioides/lesiones , Lactante , Recién Nacido , Modelos Lineales , Masculino , Persona de Mediana Edad , Osteogénesis , Determinación del Sexo por el Esqueleto , Adulto Joven
13.
Clin Anat ; 26(4): 522-30, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23553712

RESUMEN

The objectives of this study were to investigate the anatomical relationship between the proximal adductor longus (AL) and rectus abdominis muscles and to determine whether unilateral loading of AL results in strain transmission across the anterior pubic symphysis to the contralateral distal rectus sheath. Bilateral dissections were conducted on 10 embalmed cadavers. Strain transfer across the pubic symphysis was examined on seven of these cadavers. An AL contraction was simulated by applying a controlled load in the direction of its proximal tendinous fibers, and the resultant strain in the contralateral distal rectus sheath was measured using a foil-type surface mounted microstrain gage. Adductor longus attached to the antero-inferior aspect of the pubis. In 18 of the 20 limbs, the proximal attachment of AL was tendinous on its superficial surface and muscular on its deep surface. The proximal AL tendon was found in most instances to have secondary communications with structures such as the contralateral distal rectus sheath, pubic symphysis anterior capsule, ilio-inguinal ligament, and contralateral proximal AL tendon. Despite these consistent anatomical observations, strain measured in the contralateral distal rectus sheath upon unilateral loading of the proximal AL varied considerably between cadavers. Measured strain had an average ± 1SD of 0.23 ± 0.43%. The proximal attachment of AL contributes to an anatomical pathway across the anterior pubic symphysis that is likely required to withstand the transmission of large forces during multidirectional athletic activities. This anatomical relationship may be a relevant factor in explaining the apparent vulnerability of the AL and rectus abdominis attachments to injury.


Asunto(s)
Músculo Esquelético/anatomía & histología , Sínfisis Pubiana/anatomía & histología , Recto del Abdomen/anatomía & histología , Muslo/anatomía & histología , Anciano , Anciano de 80 o más Años , Fenómenos Biomecánicos , Cadáver , Femenino , Humanos , Ligamentos/anatomía & histología , Masculino , Tendones/anatomía & histología , Soporte de Peso
14.
Forensic Sci Med Pathol ; 9(3): 377-85, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23794193

RESUMEN

Recognition of injury to the hyoid bone and thyroid and cricoid cartilages is intrinsic to post-mortem examination. Due to its increasing brittleness with age the thyroid cartilage is particularly susceptible to injury following neck trauma, although there is inconsistency in the patterns of injury reported. In this study computed tomography scans of the head and neck of 431 deceased persons (235 males and 196 females) between the ages of 1 day and 100 years (mean age 35.93 ± 24.15), and including 25 victims of hangings, were examined to reveal the pattern of age-related change and the types of injury that occurred. Thyroid cartilage anomalies likely to cause confusion and be misinterpreted as trauma-related are documented. Angulation of the thyroid cartilage horns was found to change with age, and it is suggested this may be a significant factor in traumatic neck injury. Unlike in previous reports, the average age of hanging victims with fractures to the thyroid cartilage was 34 years. The base of the superior horn was the most common fracture site and in 50 % of hanging cases was associated with a ligature positioned on the thyrohyoid membrane or thyroid lamina. Although an age-related relationship exists it was not possible to establish narrow age-prediction ranges from calcification of the thyroid cartilage.


Asunto(s)
Patologia Forense/métodos , Traumatismos del Cuello/diagnóstico por imagen , Cartílago Tiroides/diagnóstico por imagen , Tomografía Computarizada Espiral , Adolescente , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Análisis de Varianza , Autopsia , Calcificación Fisiológica , Niño , Preescolar , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Reproducibilidad de los Resultados , Cartílago Tiroides/anomalías , Cartílago Tiroides/crecimiento & desarrollo , Cartílago Tiroides/lesiones , Victoria , Adulto Joven
15.
Int J Legal Med ; 126(2): 251-7, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21947631

RESUMEN

The prevalence of developmental asymmetry between left and right sides of the body in the third molar tooth and medial clavicular epiphysis is examined in a contemporary Australian population (92% Caucasian). The contention that differences between left and right side developmental timing is statistically insignificant, and can therefore be ignored in forensic age estimation procedures, is questioned. It was found that of a population sample of 604 individuals, 177 displayed asymmetrical timing in development between antimeres of the third molar, the medial clavicle or both. There was no correlation found between the third molar tooth and medial clavicular epiphysis in terms of left/right synchronicity. For those individuals differing in development by two or more developmental stages in either age marker or one stage in both age markers, the effect upon the accuracy of forensic age estimations can be significant. Differences in age estimates for each side were as much as 3.1 years. Age estimations based on one side only may not provide the best estimate for an individual, and more accurate results can be achieved if both sides are taken into consideration. A protocol for dealing with asymmetrical development is discussed with reference to the multifactorial age estimation method proposed by the same authors in previous research.


Asunto(s)
Determinación de la Edad por el Esqueleto/estadística & datos numéricos , Determinación de la Edad por los Dientes , Clavícula/diagnóstico por imagen , Medicina Legal/estadística & datos numéricos , Adolescente , Adulto , Determinación de la Edad por el Esqueleto/métodos , Determinación de la Edad por los Dientes/métodos , Australia/epidemiología , Clavícula/crecimiento & desarrollo , Femenino , Odontología Forense/métodos , Odontología Forense/estadística & datos numéricos , Medicina Legal/métodos , Humanos , Incidencia , Masculino , Adulto Joven
16.
Conserv Physiol ; 10(1): coac075, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36570735

RESUMEN

Migrating birds face a myriad of hazards, including higher exposure to parasites and numerous competing energy demands. It follows that migration may act as a selective filter and limit population growth. Understanding how individual-level physiological condition and disease status scale up to population dynamics through differential survival of individuals is necessary to identify threats and management interventions for migratory populations, many of which face increasing conservation challenges. However, linking individual physiological condition, parasite infection status and survival can be difficult. We examined the relationship among two measures of physiological condition [scaled-mass index and heterophil/leukocyte (H/L) ratio], hematozoa (i.e. hemoparasites) presence and abundance, and constitutive immunity in 353 autumn migrating red-tailed hawks (Buteo jamaicensis calurus) from 2004 to 2018. Hematazoa (i.e. Haemoproteus and Leucocytozoon) were in the blood smears from 139 red-tailed hawks (39.4%). H/L ratio decreased with scaled-mass index. Adults had a significantly higher H/L ratio than juveniles. Our two measures of immune defences, hemolytic-complement activity and bacteria-killing ability, were highly positively correlated. Our most notable finding was a negative relationship between Haemoproteus parasitemia and survival (i.e. documented individual mortality), indicating that haemosporidian parasites influence survival during a challenging life stage. The effect of haemosporidian parasites on individuals is often debated, and we provide evidence that parasitemia can affect individual survival. In contrast, we did not find evidence of trade-offs between survival and immune defences.

17.
Integr Comp Biol ; 62(6): 1693-1699, 2022 12 30.
Artículo en Inglés | MEDLINE | ID: mdl-35294024

RESUMEN

Comparative analyses in biology rely on the quality of available data. Methodological differences among studies may introduce variation in results that obscure patterns. In the field of eco-immunology, functional immune assays such as antimicrobial capacity assays are widely used for among-species applications. Sample storage time and animal handling time can influence assay results in some species, but how sample holding time prior to freezing influences assay results is unknown. Sample holding time can vary widely in field studies on wild animals, prompting the need to understand the implications of such variation on assay results. We investigated the hypothesis that sample holding time prior to freezing influences assay results in six species (Leiocephalus carinatus, Iguana iguana, Loxodonta africana, Ceratotherium simum, Columba livia, and Buteo swainsoni) by comparing antibacterial capacity of serum with varying processing times prior to snap-freezing. Blood was collected once from each individual and aliquots were placed on ice and assigned different holding times (0, 30, 60, 180, and 240 min), after which each sample was centrifuged, then serum was separated and snap-frozen on dry ice and stored at -80ºC for 60 days prior to assaying. For each aliquot, we conducted antibacterial capacity assays with serial dilutions of serum inoculated with E. coli and extracted the dilution at 50% antibacterial capacity for analysis. We found a decrease in antibacterial capacity with increased holding time in one of the six species tested (B. swainsoni), driven in part by complete loss of antibacterial capacity in some individuals at the 240-min time point. While the majority of species' antibacterial capacity were not affected, our results demonstrate the need to conduct pilot assays spanning the anticipated variation in sample holding times to develop appropriate field protocols.


Asunto(s)
Columbidae , Escherichia coli , Animales , Congelación , Antibacterianos
18.
J Urol ; 185(4): 1519-25, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21334677

RESUMEN

PURPOSE: An accurate, complete understanding of the prostate neuroanatomy is required to optimize nerve sparing techniques during radical prostatectomy. However, the precise topography and function of the periprostatic nerves remain contentious and there is uncertainty about which nerve sparing technique is most optimal. We accurately quantified the distribution, precise localization and cross-sectional area of periprostatic neural tissue using cadaveric specimens. MATERIALS AND METHODS: We analyzed 13 cadaveric hemipelves using hematoxylin and eosin stained sections from the base, mid zone and apex of each prostate. Each section was digitized and divided into 6 sectors numbered clockwise. Analysis was performed using National Institutes of Health ImageJ software to calculate the total periprostatic neural cross-sectional area per sector. RESULTS: Calculating the total neural cross-sectional area highlighted a decrease from prostate base to mid zone to apex of 24.7, 19.7 and 13.7 mm(2), respectively. Most neural tissue was located in the posterolateral region. However, the proportion surrounding the anterior part of the prostate increased toward the apex with a median of 6.0% and 7.6% at the base and mid zone regions, respectively, increasing to 11.2% at the apex. CONCLUSIONS: Simple numerical nerve quantification may be insufficient to accurately describe the periprostatic neural distribution. Calculating nerve bundle cross-sectional area confirmed that most neural tissue is in the posterolateral region, although the proportion located anterior increases from base to apex. Thus, higher release of the periprostatic fascia may be indicated toward the apex.


Asunto(s)
Próstata/inervación , Prostatectomía/métodos , Anciano , Cadáver , Humanos , Masculino
19.
Forensic Sci Med Pathol ; 7(2): 148-54, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21057985

RESUMEN

This study was designed in order to assess the suitability of clavicular development in discriminating whether or not an individual has reached the age of 18 years. The development of the medial clavicular epiphysis was examined in an Australian population using computed tomography as the imaging modality. The sample consisted of individuals who were admitted to the Victorian Institute of Forensic Medicine, Melbourne, Australia, for the purposes of medico-legal death investigation. Comparisons were made with similar studies conducted on different populations in other countries, which revealed that the Australian population reaches maturity earlier, and the level of left/right asymmetry is higher than in other studies. The high degree of variation in fusion times is discussed, and the consequent effect upon the ability to use this epiphysis as a tool for determining if an individual has reached the age of 18 years is analysed. If an individual in this population has completely fused clavicles at stage 5, then for males they will be at least 18 years of age, with a 99% certainty of being at least 21, and for females they will be at least 20 years old. If at stage three then an individual of either sex will be at least 17 years of age.


Asunto(s)
Determinación de la Edad por el Esqueleto/métodos , Clavícula/anatomía & histología , Epífisis/anatomía & histología , Antropología Forense/métodos , Tomografía Computarizada por Rayos X/métodos , Adolescente , Adulto , Determinación de la Edad por el Esqueleto/instrumentación , Australia , Clavícula/diagnóstico por imagen , Clavícula/crecimiento & desarrollo , Epífisis/diagnóstico por imagen , Epífisis/crecimiento & desarrollo , Femenino , Antropología Forense/instrumentación , Humanos , Masculino , Adulto Joven
20.
Br J Hosp Med (Lond) ; 82(3): 1-2, 2021 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-33792395

RESUMEN

Lung-protective ventilation significantly reduces mortality in patients with acute respiratory distress syndrome, but do the advantages of this approach transfer from the intensive care unit to the operating room?


Asunto(s)
Respiración Artificial , Síndrome de Dificultad Respiratoria , Humanos , Unidades de Cuidados Intensivos , Pulmón , Síndrome de Dificultad Respiratoria/terapia , Volumen de Ventilación Pulmonar
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