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1.
Phys Rev Lett ; 129(3): 034101, 2022 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-35905369

RESUMO

The present work considers systems whose dynamics are governed by the nonlinear interactions among groups of 6 nonlinear waves, such as those described by the unforced quintic nonlinear Schrödinger equation. Specific parameter regimes in which ensemble-averaged dynamics of such systems with finite size are accurately described by a wave kinetic equation, as used in wave turbulence theory, are theoretically predicted. In addition, the underlying reasons that the wave kinetic equation may be a poor predictor of wave dynamics outside these regimes are also discussed. These theoretical predictions are directly verified by comparing ensemble averages of solutions to the dynamical equation with corresponding solutions of the wave kinetic equation.

2.
Public Health ; 206: 15-19, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35306193

RESUMO

INTRODUCTION: Rental electric scooters (e-scooters) have become more available to the UK public following amendments to legislation in 2020 affecting rideshare schemes. Existing literature from outside the UK demonstrates a worrying trend of increasing injuries related to their use and non-compliance with suggested safety precautions. An e-scooter rideshare scheme trial began in Liverpool in October 2020. We intended to identify the musculoskeletal injury rate and describe the injuries sustained during this pilot. METHODS: Data were collected retrospectively from electronic patient records on all patients at a major trauma centre covering the whole of the Liverpool rideshare trial site presenting with e-scooter and bicycle musculoskeletal injuries between the trial start on 6th October 2020 and 5th May 2021 and between 6th March 2020 and 5th October 2020. Data on rental e-scooter use were obtained from the rideshare operator. RESULTS: Fifty-one patients sustained musculoskeletal injuries involving e-scooters during the trial period and six injuries before the trial. Two-thirds of injuries were on rental e-scooters. We calculate an orthopaedic injury rate of 26.1 injuries per million km on e-scooters and 24.1 injuries per million km on bicycles. Over 70% of e-scooter patients had upper limb injuries, over 50% had lower limb injuries and 15.7% of patients required surgery. CONCLUSIONS: We observed an increase in musculoskeletal injuries presenting to hospital during the e-scooter pilot. Rates of musculoskeletal injuries were comparable to rates of injuries sustained on bicycles. E-scooters should be regulated closely and further safety measures introduced to minimise the rate of injuries.


Assuntos
Acidentes de Trânsito , Ciclismo , Dispositivos de Proteção da Cabeça , Humanos , Estudos Retrospectivos , Reino Unido/epidemiologia
3.
Br J Surg ; 108(4): 388-394, 2021 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-33749771

RESUMO

BACKGROUND: Breast angiosarcomas are rare tumours of vascular origin. Secondary angiosarcoma occurs following radiotherapy for breast cancer. Angiosarcomas have high recurrence and poor survival rates. This is concerning owing to the increasing use of adjuvant radiotherapy for the treatment of invasive breast cancer and ductal cancer in situ (DCIS), which could explain the rising incidence of angiosarcoma. Outcome data are limited and provide a poor evidence base for treatment. This paper presents a national, trainee-led, retrospective, multicentre study of a large angiosarcoma cohort. METHODS: Data for patients with a diagnosis of breast/chest wall angiosarcoma between 2000 and 2015 were collected retrospectively from 15 centres. RESULTS: The cohort included 183 patients with 34 primary and 149 secondary angiosarcomas. Median latency from breast cancer to secondary angiosarcoma was 6 years. Only 78.9 per cent of patients were discussed at a sarcoma multidisciplinary team meeting. Rates of recurrence were high with 14 of 28 (50 per cent ) recurrences in patients with primary and 80 of 124 (64.5 per cent ) in those with secondary angiosarcoma at 5 years. Many patients had multiple recurrences: total of 94 recurrences in 162 patients (58.0 per cent). Median survival was 5 (range 0-16) years for patients with primary and 5 (0-15) years for those with secondary angiosarcoma. Development of secondary angiosarcoma had a negative impact on predicted breast cancer survival, with a median 10-year PREDICT prognostic rate of 69.6 per cent, compared with 54.0 per cent in the observed cohort. CONCLUSION: A detrimental impact of secondary angiosarcoma on breast cancer survival has been demonstrated. Although not statistically significant, almost all excess deaths were attributable to angiosarcoma. The increased use of adjuvant radiotherapy to treat low-risk breast cancer and DCIS is a cause for concern and warrants further study.


Assuntos
Neoplasias da Mama/secundário , Hemangiossarcoma/secundário , Recidiva Local de Neoplasia/epidemiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/mortalidade , Neoplasias da Mama/patologia , Neoplasias da Mama/terapia , Feminino , Hemangiossarcoma/epidemiologia , Hemangiossarcoma/mortalidade , Hemangiossarcoma/terapia , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/terapia , Estudos Retrospectivos , Análise de Sobrevida , Parede Torácica/patologia , Resultado do Tratamento
4.
J Urol ; 204(4): 691-700, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32250729

RESUMO

PURPOSE: Prostate specific antigen has limited performance in detecting prostate cancer. The transcription factor GATA2 is expressed in aggressive prostate cancer. We analyzed the predictive value of urine extracellular vesicle GATA2 mRNA alone and in combination with a multigene panel to improve detection of prostate cancer and high risk disease. MATERIALS AND METHODS: GATA2 mRNA was analyzed in matched extracellular vesicles isolated from urines before and after prostatectomy (16) and paired urine and tissue prostatectomy samples (19). Extracellular vesicle GATA2 mRNA performance to distinguish prostate cancer and high grade disease was tested in training (52) and validation (165) cohorts. The predictive value of a multigene score including GATA2, PCA3 and TMPRSS2-ERG (GAPT-E) was tested in both cohorts. RESULTS: Confirming its prostate origin, urine extracellular vesicle GATA2 mRNA levels decreased significantly after prostatectomy and correlated with prostate cancer tissue GATA2 mRNA levels. In the training and validation cohort GATA2 discriminated prostate cancer (AUC 0.74 and 0.66) and high grade disease (AUC 0.78 and 0.65), respectively. Notably, the GAPT-E score improved discrimination of prostate cancer (AUC 0.84 and 0.72) and high grade cancer (AUC 0.85 and 0.71) in both cohorts when compared with each biomarker alone and PT-E (PCA3 and TMPRSS2-ERG). A GAPT-E score for high grade prostate cancer would avoid 92.1% of unnecessary prostate biopsies, compared to 61.9% when a PT-E score is used. CONCLUSIONS: Urine extracellular vesicle GATA2 mRNA analysis improves the detection of high risk prostate cancer and may reduce the number of unnecessary biopsies.


Assuntos
Vesículas Extracelulares/química , Fator de Transcrição GATA2/genética , Próstata/patologia , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , RNA Mensageiro/análise , Idoso , Idoso de 80 Anos ou mais , Biópsia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
5.
Ecotoxicology ; 29(3): 237-245, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32060669

RESUMO

Pollinator decline worldwide is well-documented; globally, chemical pesticides (especially the class of pesticides known as neonicotinoids) have been implicated in hymenopteran decline, but the mechanics and drivers of population trends and dynamics of wild bees is poorly understood. Declines and shifts in community composition of bumble bees (Bombus spp.) have been documented in North America and Europe, with a suite of lethal and sub-lethal effects of pesticides on bumble bee populations documented. We employ a mathematical model parameterized with values taken from the literature that uses differential equations to track bumble bee populations through time in order to attain a better understanding of toxicant effects on a developing colony of bumble bees. We use a delay differential equation (DDE) model, which requires fewer parameter estimations than agent-based models while affording us the ability to explicitly describe the effect of larval incubation and colony history on population outcomes. We explore how both lethal and sublethal effects such as reduced foraging ability may combine to affect population outcomes, and discuss the implications for the protection and conservation of ecosystem services.


Assuntos
Abelhas/fisiologia , Monitoramento Ambiental , Substâncias Perigosas/toxicidade , Agricultura , Animais , Ecossistema , Neonicotinoides/toxicidade , Praguicidas/toxicidade , Polinização
6.
Surgeon ; 18(5): e1-e6, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31718929

RESUMO

BACKGROUND: Changes to working practices and increasing service demand have contributed to low morale amongst UK surgical trainees, with pressures particularly acute 'out of hours' (OOH). Surgeons may be expected to be 'on call' for multiple hospitals, or to provide remote consultations, yet healthcare systems may undermine their professional safety and patient care. This cross-sectional study sought to define the perceptions of UK-based Royal College of Surgeons of Edinburgh (RCSEd) affiliated trainees of OOH surgical care and training. METHODS: The RCSEd Trainees' Committee conducted a design-thinking exercise to produce an online questionnaire. Non-consultant grade RCSEd Members and Fellows were invited to participate. Quantitative data was analysed using descriptive statistics, and qualitative data was coded to identify emergent themes. RESULTS: One hundred and fifty-five surgeons participated. Of those surgeons working in multiple hospitals OOH (n = 16), many did not receive access cards (12[75%]) or site-specific induction (13[81%]), and 8(50%) were not confident in using local electronic investigation and records systems. Only 14/114 (12%) of the surgeons providing remote opinion had access to a consultation record system, and most perceived dissatisfaction with the system. Emergent themes from qualitative data revealed that trainee surgeons desire specific training in OOH working, concerns that OOH work experience is diminishing, and that hospital infrastructure such as IT and communications, rest facilities and catering were inadequate in facilitating safe care. CONCLUSIONS: The participants perceived that the systems supporting delivery of safe surgical care OOH were inadequate. Hospital leaders should ensure that systems minimise risk to staff and patients.


Assuntos
Plantão Médico/organização & administração , Educação de Pós-Graduação em Medicina/organização & administração , Cirurgia Geral/educação , Admissão e Escalonamento de Pessoal/organização & administração , Medicina Estatal , Competência Clínica , Estudos Transversais , Humanos , Inquéritos e Questionários , Reino Unido , Carga de Trabalho
7.
J Evol Biol ; 31(4): 484-490, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29345015

RESUMO

Much of our current state of knowledge concerning sex chromosome evolution is based on a handful of 'exceptional' taxa with heteromorphic sex chromosomes. However, classifying the sex chromosome systems of additional species lacking easily identifiable, heteromorphic sex chromosomes is indispensable if we wish to fully understand the genesis, degeneration and turnover of vertebrate sex chromosomes. Squamate reptiles (lizards and snakes) are a potential model clade for studying sex chromosome evolution as they exhibit a suite of sex-determining modes yet most species lack heteromorphic sex chromosomes. Only three (of 203) chameleon species have identified sex chromosome systems (all with female heterogamety, ZZ/ZW). This study uses a recently developed method to identify sex-specific genetic markers from restriction site-associated DNA sequence (RADseq) data, which enables the identification of sex chromosome systems in species lacking heteromorphic sex chromosomes. We used RADseq and subsequent PCR validation to identify an XX/XY sex chromosome system in the veiled chameleon (Chamaeleo calyptratus), revealing a novel transition in sex chromosome systems within the Chamaeleonidae. The sex-specific genetic markers identified here will be essential in research focused on sex-specific, comparative, functional and developmental evolutionary questions, further promoting C. calyptratus' utility as an emerging model organism.


Assuntos
Lagartos/genética , Cromossomos Sexuais , Animais , Feminino , Masculino
8.
Br J Surg ; 104(9): 1123-1130, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28656693

RESUMO

BACKGROUND: Surgical-site infections (SSIs) increase patient morbidity and costs. The aim was to identify and synthesize all RCTs evaluating the effect of topical antibiotics on SSI in wounds healing by primary intention. METHODS: The search included Ovid MEDLINE, Ovid Embase, the Cochrane Wounds Specialized Register, Central Register of Controlled Trials and EBSCO CINAHL from inception to May 2016. There was no restriction of language, date or setting. Two authors independently selected studies, extracted data and assessed risk of bias. When sufficient numbers of comparable trials were available, data were pooled in meta-analysis. RESULTS: Fourteen RCTs with 6466 participants met the inclusion criteria. Pooling of eight trials (5427 participants) showed that topical antibiotics probably reduced the risk of SSI compared with no topical antibiotic (risk ratio (RR) 0·61, 95 per cent c.i. 0·42 to 0·87; moderate-quality evidence), equating to 20 fewer SSIs per 1000 patients treated. Pooling of three trials (3012 participants) for risk of allergic contact dermatitis found no clear difference between antibiotics and no antibiotic (RR 3·94, 0·46 to 34·00; very low-quality evidence). Pooling of five trials (1299 participants) indicated that topical antibiotics probably reduce the risk of SSI compared with topical antiseptics (RR 0·49, 0·30 to 0·80; moderate-quality evidence); 43 fewer SSIs per 1000 patients treated. Pooling of two trials (541 participants) showed no clear difference in the risk of allergic contact dermatitis with antibiotics or antiseptic agents (RR 0·97, 0·52 to 1·82; very low-quality evidence). CONCLUSION: Topical antibiotics probably prevent SSI compared with no topical antibiotic or antiseptic. No conclusion can be drawn regarding whether they cause allergic contact dermatitis.


Assuntos
Antibacterianos/administração & dosagem , Anti-Infecciosos Locais/administração & dosagem , Infecção da Ferida Cirúrgica/prevenção & controle , Antibacterianos/efeitos adversos , Anti-Infecciosos Locais/efeitos adversos , Toxidermias/etiologia , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Técnicas de Fechamento de Ferimentos , Cicatrização/efeitos dos fármacos
9.
Phys Rev Lett ; 119(5): 055002, 2017 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-28949748

RESUMO

Ion acoustic waves are found to be susceptible to at least two distinct decay processes. Which process dominates depends on the parameters. In the cases examined, the decay channel where daughter modes propagate parallel to the mother mode is found to dominate at larger amplitudes, while the decay channel where the daughter modes propagate at angles to the mother mode dominates at smaller amplitudes. Both decay processes may occur simultaneously and with onset thresholds below those suggested by fluid theory, resulting in the eventual multidimensional collapse of the mother mode to a turbulent state.

10.
Ir Med J ; 115(1): 513, 2022 01 20.
Artigo em Inglês | MEDLINE | ID: mdl-35279047
11.
Appl Math Lett ; 43: 10-18, 2015 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-25574073

RESUMO

In the context of inverse or parameter estimation problems we demonstrate the use of statistically based model comparison tests in several examples of practical interest. In these examples we are interested in questions related to information content of a particular given data set and whether the data will support a more complicated model to describe it. In the first example we compare fits for several different models to describe simple decay in a size histogram for aggregates in amyloid fibril formation. In a second example we investigate whether the information content in data sets for the pest Lygus hesperus in cotton fields as it is currently collected is sufficient to support a model in which one distinguishes between nymphs and adults. Finally in a third example with data for patients having undergone an organ transplant, we question whether the data content is sufficient to estimate more than 5 of the fundamental parameters in a particular dynamic model.

12.
Annu Rev Entomol ; 59: 383-404, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24160417

RESUMO

Many farmers rely on regular pesticide applications to avoid losses from arthropod pests and the diseases they vector. However, widespread and injudicious use of pesticides is detrimental to the environment, poses a health risk, and undermines biocontrol services. Researchers are increasingly required to develop techniques to quantify the trade-offs and risks associated with pesticides. Laboratory studies, though useful for assessing short-term impacts (e.g., mortality), cannot detect longer-term or indirect effects that can potentially be assessed using semifield studies. Here we review the range and scope of studies that have used semifield methods for regulatory testing and risk assessment of pesticides and for understanding the community-level effects of pesticide use in agricultural landscapes. We include studies on target and nontarget species, with an emphasis on quantifying effects when the target species is highly mobile. We suggest improvements in the design and analysis of semifield studies to more effectively assess effects on highly mobile species.


Assuntos
Ecotoxicologia/métodos , Invertebrados/efeitos dos fármacos , Praguicidas/farmacologia , Agricultura , Animais , Meio Ambiente , Medição de Risco/métodos
13.
Euro Surveill ; 19(18)2014 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-24832117

RESUMO

Factors that trigger human infection with animal influenza virus progressing into a pandemic are poorly understood. Within a project developing an evidence-based risk assessment framework for influenza viruses in animals, we conducted a review of the literature for evidence of human infection with animal influenza viruses by diagnostic methods used. The review covering Medline, Embase, SciSearch and CabAbstracts yielded 6,955 articles, of which we retained 89; for influenza A(H5N1) and A(H7N9), the official case counts of t he World Health Organization were used. An additional 30 studies were included by scanning the reference lists. Here, we present the findings for confirmed infections with virological evidence. We found reports of 1,419 naturally infected human cases, of which 648 were associated with avian influenza virus (AIV) A(H5N1), 375 with other AIV subtypes, and 396 with swine influenza virus (SIV). Human cases naturally infected with AIV spanned haemagglutinin subtypes H5, H6, H7, H9 and H10. SIV cases were associated with endemic SIV of H1 and H3 subtype descending from North American and Eurasian SIV lineages and various reassortants thereof. Direct exposure to birds or swine was the most likely source of infection for the cases with available information on exposure.


Assuntos
Virus da Influenza A Subtipo H5N1/patogenicidade , Influenza Aviária/virologia , Influenza Humana/virologia , Zoonoses , Animais , Aves , Humanos , Influenza Aviária/transmissão , Influenza Humana/transmissão , Suínos
14.
Ann R Coll Surg Engl ; 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-39081169

RESUMO

INTRODUCTION: Up to 30% of patients with colorectal cancer present as an emergency and have worse outcomes than elective patients. Compared with left-sided cancers, malignancies arising in the right colon are significantly under-researched. We sought to compare cancer care quality and clinical outcomes between emergency and elective presentations of right-sided colon cancer (RCC). METHODS: This multicentre, retrospective study included all patients who underwent operative management for a RCC, from 1 April 2017 to 31 March 2022. Data were collected from electronic patient records, and host and tumour factors as well as outcomes between emergency and elective cohorts were compared. RESULTS: Overall, 806 patients (median age 72 years) were included. Some 175 patients (22%) presented as an emergency: 140 in obstruction and 35 with tumour perforation, compared with 1 patient with tumour perforation in the elective group (p < 0.001). The emergency group had higher rates of postoperative complications (59.1% vs 20.0%, p < 0.001), increased 90-day mortality (13.7% vs 1.3%, p < 0.001) and a longer hospital stay (5 vs 10 days, p < 0.001). From the emergency cohort only 29.2% of eligible patients received adjuvant chemotherapy and in multivariate regression analysis emergency presentation was associated with a decreased likelihood of receiving adjuvant chemotherapy (odds ratio 0.26 [0.14-0.47], p < 0.001). CONCLUSIONS: Both short- and long-term outcomes after emergency presentation of RCC are poor, with inadequate access to subsequent chemotherapy. Strategies addressing emergency presentations of left-sided tumours have moved towards temporisation and elective surgery. Delaying major resectional surgery for optimisation may improve outcomes and access to adjuvant therapies for RCC.

15.
Clin Oncol (R Coll Radiol) ; 36(1): e31-e39, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38294995

RESUMO

AIMS: Phyllodes tumours and breast sarcomas are uncommon tumours and their rarity poses significant challenges in diagnosis and management. This cross-sectional study was conducted to evaluate the multidisciplinary clinical practice for these tumours across the UK and Ireland, with the aim of identifying gaps in knowledge and providing direction for establishing national guidelines. MATERIALS AND METHODS: An international survey was adapted and circulated to breast and/or sarcoma surgeons and oncologists in the UK and Ireland through national organisations. Multidisciplinary team (MDT) responses were analysed anonymously. RESULTS: Twenty-eight MDTs participated in this study, predominately from high-volume units (85.5%). Although only 43% of the surveyed units were part of a trust that holds a sarcoma MDT, 68% of units managed malignant phyllodes and angiosarcoma, whereas 64.5% managed soft-tissue sarcoma of the breast. Across all subtypes, axillary surgery was recommended by 14-21% of the MDTs and the most recommended resection margins for breast surgery were 'no tumour on ink' in benign phyllodes (39%) and 10 mm in the remaining subtypes (25-29%). Immediate breast reconstruction was supported by 11-18% of MDTs for breast sarcoma subtypes, whereas 36% and 32% advocated this approach in benign and borderline phyllodes tumours, respectively. Adjuvant radiotherapy and chemotherapy were recommended by up to 29% and 11% of the MDTs, respectively. CONCLUSION: The results of this study demonstrate a wide variation in clinical practice across the surveyed MDTs. As only 28 MDTs participated in our study, with under-representation from low-volume units, our results might be an underestimation of the variability in practice across the UK and Ireland. This multi-institutional study sheds light on controversial aspects in the management of phyllodes tumours and breast sarcoma, identifies the need for national guidelines to inform best practice, and calls for the centralisation of the management of breast sarcoma within specialist centres.


Assuntos
Neoplasias da Mama , Tumor Filoide , Sarcoma , Neoplasias de Tecidos Moles , Humanos , Feminino , Tumor Filoide/epidemiologia , Tumor Filoide/cirurgia , Estudos Transversais , Irlanda/epidemiologia , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/cirurgia , Sarcoma/epidemiologia , Sarcoma/cirurgia , Reino Unido/epidemiologia , Recidiva Local de Neoplasia/patologia
16.
Phys Rev Lett ; 111(10): 105002, 2013 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-25166675

RESUMO

Two-dimensional simulations, both Vlasov and particle-in-cell, are presented that show the evolution of the field and electron distribution of finite-width, nonlinear electron plasma waves. The intrinsically intertwined effects of self-focusing and dissipation of field energy caused by electron trapping are studied in simulated systems that are hundreds of wavelengths long in the transverse direction but only one wavelength long and periodic in the propagation direction. From various initial wave states, both the width at focus Δm relative to the initial width Δ0 and the maximum field amplitude at focus are shown to be a function of the growth rate of the transverse modulational instability γTPMI divided by the loss rate of field energy νE to electrons escaping the trapping region. With dissipation included, an amplitude threshold for self-focusing γTPMI/νE∼1 is found that supports the analysis of Rose [Phys. Plasmas 12, 012318 (2005)].

17.
Drug Test Anal ; 14(8): 1539-1546, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35478494

RESUMO

Laboratories are challenged to distinguish whether a positive urine morphine result is due to heroin use or possible poppy seed consumption. Thebaine is an opium alkaloid that has been shown to be present in the urine of individuals who have consumed poppy seeds, as well as those who have used opium. It is not present in heroin. We present a sensitive, specific liquid chromatography tandem mass spectrometry (LC-MS/MS) assay for thebaine. We show that thebaine is detectable after consumption of two different poppy seed-containing products for up to 72 h in urine. We discuss limitations of the assay and suggest how the test might best be used.


Assuntos
Papaver , Tebaína , Cromatografia Líquida , Cromatografia Gasosa-Espectrometria de Massas/métodos , Heroína/análise , Humanos , Morfina/urina , Ópio/análise , Papaver/química , Sementes/química , Espectrometria de Massas em Tandem/métodos
18.
Ann R Coll Surg Engl ; 104(9): e249-e251, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35638901

RESUMO

A 73-year-old woman presented with small bowel obstruction that failed to settle with conservative management. Over the previous 2 years she had presented twice with computed tomography scan-proven acute appendicitis with localised perforation of the appendix tip. In view of medical comorbidities, she was treated non-operatively with clinical and radiological resolution on each occasion, but on the third presentation laparoscopy was undertaken for non-resolving small bowel obstruction and the non-inflamed appendix itself was identified as a fibrous band causing compression of the distal ileum and complete small bowel obstruction. Following division and appendicectomy, the patient made an uneventful recovery. This case illustrates the potential consequence of repeated appendiceal inflammation and non-operative management and may be seen increasingly as this approach is widely adopted during the COVID-19 pandemic.


Assuntos
Apendicite , Apêndice , COVID-19 , Obstrução Intestinal , Feminino , Humanos , Idoso , Apendicite/complicações , Apendicite/cirurgia , Apêndice/diagnóstico por imagem , Apêndice/cirurgia , Pandemias , Apendicectomia/efeitos adversos , Obstrução Intestinal/etiologia , Obstrução Intestinal/cirurgia , Doença Aguda
19.
Hernia ; 26(1): 297-307, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-33433739

RESUMO

PURPOSE: Before being marketed, hernia mesh must undergo in vivo testing, which often includes biomechanical and histological assessment. Currently, there are no universal standards for this testing and methods vary greatly within the literature. A scoping review of relevant studies was undertaken to analyse the methodologies used for in vivo mesh testing. METHODS: Medline and Embase databases were searched for relevant studies. 513 articles were identified and 231 duplicates excluded. 126 papers were included after abstract and full text review. The data extraction was undertaken using standardised forms. RESULTS: Mesh is most commonly tested in rats (53%). 78% of studies involve the formation of a defect; in 52% of which the fascia is not opposed. The most common hernia models use mesh to bridge an acute defect (50%). Tensile strength testing is the commonest form of mechanical testing (63%). Testing strip widths and test speeds vary greatly (4-30 mm and 1.625-240 mm/min, respectively). There is little consensus on which units to use for tensile strength testing. Collagen is assessed for its abundance (54 studies) more than its alignment (18 studies). Alignment is not measured quantitatively. At least 21 histological scoring systems are used for in vivo mesh testing. CONCLUSIONS: The current practice of in vivo mesh testing lacks standardisation. There is significant inconsistency in every category of testing, both in methodology and comparators. We would call upon hernia organisations and materials testing institutions to discuss the need for a standardised approach to this field.


Assuntos
Herniorrafia , Telas Cirúrgicas , Animais , Hérnia , Herniorrafia/métodos , Humanos , Teste de Materiais , Próteses e Implantes , Ratos , Telas Cirúrgicas/efeitos adversos , Resistência à Tração
20.
Gen Comp Endocrinol ; 173(1): 139-47, 2011 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-21624370

RESUMO

To understand how the social and physical environment influences behaviour, reproduction and survival, studies of underlying hormonal processes are crucial; in particular, interactions between stress and reproductive responses may have critical influences on breeding schedules. Several authors have examined the timing of breeding in relation to environmental stimuli, while others have independently described endocrine profiles. However, few studies have simultaneously measured endocrine profiles, breeding behaviour, and offspring survival across seasons. We measured sex and stress hormone concentrations (oestrogens, testosterone, and corticosterone), timing of breeding, and chick survival, in Adelie penguins (Pygoscelis adeliae) at two colonies in two different years. Clutch initiation at Cape Bird South (CBS; year 1, ~14,000 pairs) occurred later than at Cape Crozier East (CCE; year 2, ~ 25,000 pairs); however, breeding was more synchronous at CBS. This pattern was probably generated by the persistence of extensive sea ice at CBS (year 1). Higher corticosterone metabolite and lower sex hormone concentrations at CBS correlated with later breeding and lower chick survival compared to at CCE - again, a likely consequence of sea ice conditions. Within colonies, sub-colony size (S, 50-100; M, 200-300; L, 500-600; XL, >1000 pairs) did not influence the onset or synchrony of breeding, chick survival, or hormone concentrations. We showed that the endocrine profiles of breeding Adelie penguins can differ markedly between years and/or colonies, and that combining measures of endocrinology, behaviour, and offspring survival can reveal the mechanisms and consequences that different environmental conditions can have on breeding ecology.


Assuntos
Reprodução/fisiologia , Spheniscidae/fisiologia , Animais , Cruzamento , Corticosterona/metabolismo , Endocrinologia , Estrogênios/metabolismo , Fezes/química , Feminino , Técnicas Imunoenzimáticas , Masculino , Spheniscidae/metabolismo , Testosterona/metabolismo
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