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Introduction: Sydney Local Health District (SLHD) is a local health district in the state of New South Wales in Australia responsible for providing health services to the centre and inner west of the Sydney metropolitan area. SLHD adopted, during the COVID-19 pandemic, an integrated virtual and community care approach to manage quarantine and protect the health and wellbeing of the population. Description: The case study describes the roles of the different agencies and teams in the first six months of the pandemic across four key functions of 1) rapid screening and testing; 2) reaching the community; 3) effective quarantine and ongoing care; and 4) infrastructure, pathology and staff education. Discussion: The "whole of system" approach proved to be an effective method of delivering care that reduced community anxiety, improved and created relationships between existing and new internal and external stakeholders, and changed the community and health sector's perspective on the importance of virtual care. Conclusion: This case study describes the importance of well-integrated, decentralised and funded public health system in response to the COVID-19 pandemic.
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The Pfizer/BioNtech BNT162b2 is a major vaccine used in the Australian COVID-19 immunisation programme. We report on BNT162b2 safety in the observation period in a dedicated vaccination clinic linked to a quaternary teaching hospital. We performed a retrospective review of medical records for 57 842 vaccinations, and describe the model of care and adverse event rate at the clinic during its first 2 months of operation. A total of 243 adverse events following immunisation (0.42% of total vaccine doses) were recorded in the immediate observation period post-vaccination, which were predominantly immunisation stress-related responses. Of the 110 patients who experienced an adverse event with their first dose of the vaccine, 90% returned for their second dose of the vaccine, with 87% not reporting any further adverse reaction with the subsequent dose. Nineteen (0.03% of total doses) people were reviewed for an allergic reaction, of which 10 (53%) reported a history of prior allergies. A female predominance was present in both total adverse reactions (70%) and allergic vaccine reactions (79%). Only two patients experienced anaphylaxis (0.003% of total doses), in keeping with low rates of adverse reactions to the BNT162b2 vaccine in the current literature. Overall, the present study reinforces the safety of BNT162b2 in the Australian population, describes vaccination completion rates after adverse events and identifies predisposing factors for rare allergic reactions to the vaccine.
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Anafilaxia , COVID-19 , Australia/epidemiología , Vacuna BNT162 , Vacunas contra la COVID-19 , Femenino , Humanos , Vacunación Masiva , Estudios Retrospectivos , SARS-CoV-2 , Vacunación/efectos adversosRESUMEN
BACKGROUND & AIMS: Unregulated activity of interleukin (IL) 22 promotes intestinal tumorigenesis in mice. IL22 binds the antagonist IL22 subunit alpha 2 (IL22RA2, also called IL22BP). We studied whether alterations in IL22BP contribute to colorectal carcinogenesis in humans and mice. METHODS: We obtained tumor and nontumor tissues from patients with colorectal cancer (CRC) and measured levels of cytokines by quantitative polymerase chain reaction, flow cytometry, and immunohistochemistry. We measured levels of Il22bp messenger RNA in colon tissues from wild-type, Tnf-/-, Lta-/-, and Ltb-/- mice. Mice were given azoxymethane and dextran sodium sulfate to induce colitis and associated cancer or intracecal injections of MC38 tumor cells. Some mice were given inhibitors of lymphotoxin beta receptor (LTBR). Intestine tissues were analyzed by single-cell sequencing to identify cell sources of lymphotoxin. We performed immunohistochemistry analysis of colon tissue microarrays from patients with CRC (1475 tissue cores, contained tumor and nontumor tissues) and correlated levels of IL22BP with patient survival times. RESULTS: Levels of IL22BP were decreased in human colorectal tumors, compared with nontumor tissues, and correlated with levels of lymphotoxin. LTBR signaling was required for expression of IL22BP in colon tissues of mice. Wild-type mice given LTBR inhibitors had an increased tumor burden in both models, but LTBR inhibitors did not increase tumor growth in Il22bp-/- mice. Lymphotoxin directly induced expression of IL22BP in cultured human monocyte-derived dendritic cells via activation of nuclear factor κB. Reduced levels of IL22BP in colorectal tumor tissues were associated with shorter survival times of patients with CRC. CONCLUSIONS: Lymphotoxin signaling regulates expression of IL22BP in colon; levels of IL22BP are reduced in human colorectal tumors, associated with shorter survival times. LTBR signaling regulates expression of IL22BP in colon tumors in mice and cultured human dendritic cells. Patients with colorectal tumors that express low levels of IL22BP might benefit from treatment with an IL22 antagonist.
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Neoplasias Colorrectales/metabolismo , Linfotoxina-alfa/metabolismo , Receptores de Interleucina/metabolismo , Anciano , Animales , Neoplasias Colorrectales/mortalidad , Neoplasias Colorrectales/patología , Modelos Animales de Enfermedad , Femenino , Humanos , Masculino , Ratones , ARN Mensajero/metabolismo , Receptores de Interleucina/genética , Tasa de SupervivenciaRESUMEN
BACKGROUND: Selinexor is an oral Selective Inhibitor of Nuclear Export compound that specifically blocks Chromosomal Region Maintenance protein 1. OBJECTIVE: To evaluate the safety and tolerability of escalating doses of selinexor plus 5-fluorouracil, leucovorin and oxaliplatin (mFOLFOX6) in metastatic colorectal cancer (mCRC) patients. METHODS: In this multicenter phase I trial, mCRC patients, eligible for oxaliplatin-based treatment, were enrolled to receive oral selinexor on days 1, 3, and 8 plus mFOLFOX6 every two weeks. Primary endpoint was the maximum tolerated dose. Secondary endpoints were toxicity, overall response rate, progression free survival, and overall survival. RESULTS: Overall, 10 patients were enrolled, who had prior treatment with oxaliplatin (6/10), irinotecan (8/10), bevacizumab (6/10) or anti-EGFR therapy (5/10). Four consecutive patients received 40 mg selinexor plus mFOLFOX6. All four experienced dose-limiting toxicities and withdrew from the study after a median of two cycles. Thus, this dose level was regarded as toxic and no further patients were evaluated at this dose. Six patients were enrolled with 20 mg selinexor plus mFOLFOX6. Despite better tolerability, four patients withdrew (patient wish) after the first cycle and only two patients continued until disease progression. Most commonly reported treatment emergent adverse events were nausea (80%), diarrhea (70%), vomiting (60%), fatigue (60%), anorexia (40%), and impaired vision (40%). Due to the short treatment exposure, no relevant clinical activity was observed. CONCLUSION: In patients with metastatic colorectal cancer, selinexor on this dose schedule plus mFOLFOX6 was not tolerable. Other dosing schedules or combinations may be evaluated. Clinical trial identifier NCT02384850.
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Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias Colorrectales/tratamiento farmacológico , Transporte Activo de Núcleo Celular , Anciano , Neoplasias Colorrectales/patología , Femenino , Fluorouracilo/administración & dosificación , Estudios de Seguimiento , Humanos , Hidrazinas/administración & dosificación , Leucovorina/administración & dosificación , Masculino , Dosis Máxima Tolerada , Persona de Mediana Edad , Metástasis de la Neoplasia , Oxaliplatino/administración & dosificación , Pronóstico , Tasa de Supervivencia , Triazoles/administración & dosificaciónRESUMEN
BACKGROUND: Esophagogastric adenocarcinoma (EGA) currently represents a main cause of cancer related death. Despite an intensified treatment for locally advanced or metastatic EGA with a doublet chemotherapy consisting of a platinum compound and a fluoropyrimidine in combination with trastuzumab for HER2-positive disease or in selected cases with docetaxel, survival remains poor. Recently, immune-oncology based strategies relevantly improved the treatment of different solid tumors and showed some promise in late or later stage trials in EGA. Notably, the combination of immunotherapy with trastuzumab to enhance anti-tumor immunity through activation of innate and adaptive immunity was beneficial in preclinical studies or clinical studies in breast cancer. METHODS: The INTEGA study is an open-label, randomized, multicenter, exploratory phase II trial designed to assess clinical performance, safety and tolerability of ipilimumab or 5-FU/folinic acid and oxaliplatin (FOLFOX) in combination with nivolumab and trastuzumab in patients with previously untreated HER2-positive, locally advanced or metastatic EGA. The primary objective is to determine the clinical performance of ipilimumab or FOLFOX in combination with nivolumab and trastuzumab in terms of overall survival. Secondary objectives are safety and tolerability, efficacy in terms of progression-free survival and objective response rate and blood-based signatures (e.g. immune response or suppression of anti-HER2 resistance) that may correlate with treatment response. DISCUSSION: Recent evidence from the phase II NCT02954536 study (oxaliplatin, capecitabine, trastuzumab and pembrolizumab) suggests the clinical feasibility of combining chemotherapy, trastuzumab and checkpoint inhibition in EGA. However, evidence for a chemotherapy-free regimen is also mounting in HER2-positive disease (NCT02689284) i.e. margetuximab and Pembrolizumab. Both studies excelled with high overall response rates and manageable toxicities. The INTEGA study aims to comparatively assess these results and select a promising new 1st line regimen which then needs to be confirmed in a randomized phase III trial. Further, the translational part of the study might help to better stratify patients and tailor treatment of either arm. TRIAL REGISTRATION: NCT03409848 24.01.2018.
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Adenocarcinoma/tratamiento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Neoplasias Esofágicas/tratamiento farmacológico , Unión Esofagogástrica/patología , Inmunoterapia/métodos , Neoplasias Gástricas/tratamiento farmacológico , Adenocarcinoma/inmunología , Adenocarcinoma/mortalidad , Adenocarcinoma/patología , Adulto , Antineoplásicos Inmunológicos/administración & dosificación , Antineoplásicos Inmunológicos/efectos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Ensayos Clínicos Fase II como Asunto , Neoplasias Esofágicas/inmunología , Neoplasias Esofágicas/mortalidad , Neoplasias Esofágicas/patología , Unión Esofagogástrica/inmunología , Femenino , Fluorouracilo/administración & dosificación , Fluorouracilo/efectos adversos , Humanos , Inhibidores de Puntos de Control Inmunológico/administración & dosificación , Inhibidores de Puntos de Control Inmunológico/efectos adversos , Inmunoterapia/efectos adversos , Ipilimumab/administración & dosificación , Ipilimumab/efectos adversos , Leucovorina/administración & dosificación , Leucovorina/efectos adversos , Masculino , Persona de Mediana Edad , Estudios Multicéntricos como Asunto , Nivolumab/administración & dosificación , Nivolumab/efectos adversos , Compuestos Organoplatinos/administración & dosificación , Compuestos Organoplatinos/efectos adversos , Supervivencia sin Progresión , Ensayos Clínicos Controlados Aleatorios como Asunto , Receptor ErbB-2/antagonistas & inhibidores , Receptor ErbB-2/metabolismo , Neoplasias Gástricas/inmunología , Neoplasias Gástricas/mortalidad , Neoplasias Gástricas/patología , Trastuzumab/administración & dosificación , Trastuzumab/efectos adversosRESUMEN
BACKGROUND: Patients undergoing chemotherapy are highly burdened by side effects. These may be caused by the pharmacodynamics of the drug or be driven by psychological factors such as negative expectations or pre-conditioning, which reflect nocebo effects. As such, negative pre-treatment expectations or prior experiences might exacerbate the burden of chemotherapy side effects. Educating patients about this nocebo effect has been put forward as a potential strategy to optimize patients' pre-treatment expectations. In this study, we evaluate whether a briefing about the nocebo effect is efficacious in reducing side effects. METHODS: In this exploratory study, a total number of n = 100 outpatients with newly diagnosed gastrointestinal cancers are randomized 1:1 to an information session about the nocebo effect (nocebo-education) or an attention control group (ACG) with matching interaction time. Assessments take place before the intervention (T1 pre), post-intervention (T1 post), and 10 days (T2) and 12 weeks (T3) after the initial chemotherapy. The primary outcomes are the patient-rated number and intensity of side effects at 10-days and at 12-weeks follow-up. Secondary outcomes include coping with side effects, tendency to misattribute symptoms, compliance intention, attitude towards the chemotherapy, co-medication to treat side effects and the clinician-rated severity of toxicity. Further analyses are conducted to investigate whether a potential beneficial effect is mediated by a change of expectations before and after the intervention. DISCUSSION: Informing patients about the nocebo effect might be an innovative and feasible intervention to reduce the burden of side effects and strengthen patients' perceived control over adverse symptoms. TRIAL REGISTRATION: The trial is registered at the German Clinical Trials Register (ID: DRKS00009501 ; retrospectively registered on March 27, 2018). The first patient was enrolled on September 29, 2015.
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Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Protocolos Clínicos , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos/prevención & control , Neoplasias Gastrointestinales/tratamiento farmacológico , Efecto Nocebo , Educación del Paciente como Asunto , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Estudios de Casos y Controles , Femenino , Humanos , MasculinoRESUMEN
Coexistence between great tits Parus major and blue tits Cyanistes caeruleus, but also other hole-nesting taxa, constitutes a classic example of species co-occurrence resulting in potential interference and exploitation competition for food and for breeding and roosting sites. However, the spatial and temporal variations in coexistence and its consequences for competition remain poorly understood. We used an extensive database on reproduction in nest boxes by great and blue tits based on 87 study plots across Europe and Northern Africa during 1957-2012 for a total of 19,075 great tit and 16,729 blue tit clutches to assess correlative evidence for a relationship between laying date and clutch size, respectively, and density consistent with effects of intraspecific and interspecific competition. In an initial set of analyses, we statistically controlled for a suite of site-specific variables. We found evidence for an effect of intraspecific competition on blue tit laying date (later laying at higher density) and clutch size (smaller clutch size at higher density), but no evidence of significant effects of intraspecific competition in great tits, nor effects of interspecific competition for either species. To further control for site-specific variation caused by a range of potentially confounding variables, we compared means and variances in laying date and clutch size of great and blue tits among three categories of difference in density between the two species. We exploited the fact that means and variances are generally positively correlated. If interspecific competition occurs, we predicted a reduction in mean and an increase in variance in clutch size in great tit and blue tit when density of heterospecifics is higher than the density of conspecifics, and for intraspecific competition, this reduction would occur when density of conspecifics is higher than the density of heterospecifics. Such comparisons of temporal patterns of means and variances revealed evidence, for both species, consistent with intraspecific competition and to a smaller extent with interspecific competition. These findings suggest that competition associated with reproductive behaviour between blue and great tits is widespread, but also varies across large spatial and temporal scales.
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Passeriformes , África del Norte , Animales , Tamaño de la Nidada , Europa (Continente) , Femenino , ReproducciónRESUMEN
The incident command system (ICS) provides a common structure to control and coordinate an emergency response, regardless of scale or predicted impact. The lessons learned from the application of an ICS for large infectious disease outbreaks are documented. However, there is scant evidence on the application of an ICS to manage a local multiagency response to a disease cluster with environmental health risks. The Sydney Local Health District Public Health Unit (PHU) in New South Wales, Australia, was notified of 5 cases of Legionnaires' disease during 2 weeks in May 2016. This unusual incident triggered a multiagency investigation involving an ICS with staff from the PHU, 3 local councils, and the state health department to help prevent any further public health risk. The early and judicious use of ICS enabled a timely and effective response by supporting clear communication lines between the incident controller and field staff. The field team was key in preventing any ongoing public health risk through inspection, sampling, testing, and management of water systems identified to be at-risk for transmission of legionella. Good working relationships between partner agencies and trust in the technical proficiency of environmental health staff aided in the effective management of the response. (Disaster Med Public Health Preparedness. 2018;12:539-542).
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Derrame de Material Biológico/tendencias , Brotes de Enfermedades/estadística & datos numéricos , Enfermedad de los Legionarios/diagnóstico , Derrame de Material Biológico/estadística & datos numéricos , Análisis por Conglomerados , Brotes de Enfermedades/prevención & control , Exposición a Riesgos Ambientales/efectos adversos , Exposición a Riesgos Ambientales/prevención & control , Humanos , Enfermedad de los Legionarios/epidemiología , Nueva Gales del Sur/epidemiología , Vigilancia de la Población/métodos , Salud Pública/métodosRESUMEN
Land-use change and intensification threaten bee populations worldwide, imperilling pollination services. Global models are needed to better characterise, project, and mitigate bees' responses to these human impacts. The available data are, however, geographically and taxonomically unrepresentative; most data are from North America and Western Europe, overrepresenting bumblebees and raising concerns that model results may not be generalizable to other regions and taxa. To assess whether the geographic and taxonomic biases of data could undermine effectiveness of models for conservation policy, we have collated from the published literature a global dataset of bee diversity at sites facing land-use change and intensification, and assess whether bee responses to these pressures vary across 11 regions (Western, Northern, Eastern and Southern Europe; North, Central and South America; Australia and New Zealand; South East Asia; Middle and Southern Africa) and between bumblebees and other bees. Our analyses highlight strong regionally-based responses of total abundance, species richness and Simpson's diversity to land use, caused by variation in the sensitivity of species and potentially in the nature of threats. These results suggest that global extrapolation of models based on geographically and taxonomically restricted data may underestimate the true uncertainty, increasing the risk of ecological surprises.
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Abejas/fisiología , Animales , Abejas/clasificación , Conservación de los Recursos Naturales , GeografíaRESUMEN
PURPOSE: To analyse a 3-year clinical patient cohort of ranibizumab treatment of exudative age-related macular degeneration (AMD), to investigate the impact on visual outcome of carrying forward the last acuity observation in drop-outs and to explore possible differences between the early and the late phase of the study. METHODS: A retrospective study of 312 eyes with neovascular AMD. The patients were followed up monthly, received three initial monthly injections of 0.5 mg ranibizumab and were re-treated pro re nata (PRN). Time-domain optical coherence tomography (TD-OCT) was used until spectral-domain (SD)-OCT was introduced during the last year of enrolment. Sixty-five patients were discontinued from the study. PRIMARY OUTCOME: change in best corrected visual acuity (BCVA). RESULTS: Best corrected visual acuity was 58.4 (CI 56.9-59.9) ETDRS (Early Treatment Diabetic Retinopathy Study) letters. At three months, it had increased by 4.1 letters (p=0.0004), at 12 months by 1.8 letters, at 24 months by 1.0 letter and at 36 months by 0.1 letter. However, if the last available acuity of drop-outs was carried forward one step and included, acuity had increased by 3.9 letters at 3 months (p<0.0001) and by 1.0 letter at 12 months but had decreased by 3.8 letters at 24 months (p=0.019) and by 4.1 letters (p=0.003) at 36 months. At 24 months, the result was significantly (p=0.030) less favourable when drop-outs were included. In patients enrolled during the late phase, BCVA was 59.3 (CI 56.7-62.0). It had increased by 5.7 letters (p<0.0001) at three months and by 5.8 letters at 12 months (p=0.0016). In patients enrolled during the early phase, BCVA was 57.9 (CI 55.0-60.8). At three months, it had increased by 3.5 letters (p=0.0008), but at 12 months, it had decreased by 2.3 letters (ns). The result at 12 months was significantly (p=0.0033) better for the late than for the early phase. The number of injections was also significantly (p=0.011) higher in the late phase. Adverse events were similar to those in earlier clinical trials. CONCLUSIONS: The results of this 3-year cohort showed that the initial average acuity could be maintained over 36 months, which was comparable to those of many other clinical cohorts. However, if the last available acuity of drop-outs was carried forward one step and included, the acuity figures would have fallen significantly. The results in patients enrolled during the late phase of the study were fairly similar to those in clinical trials.
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Anticuerpos Monoclonales Humanizados/administración & dosificación , Mácula Lútea/patología , Degeneración Macular/tratamiento farmacológico , Anciano , Relación Dosis-Respuesta a Droga , Femenino , Estudios de Seguimiento , Humanos , Inyecciones Intravítreas , Mácula Lútea/efectos de los fármacos , Degeneración Macular/diagnóstico , Degeneración Macular/fisiopatología , Masculino , Ranibizumab , Estudios Retrospectivos , Factores de Tiempo , Tomografía de Coherencia Óptica , Resultado del Tratamiento , Agudeza VisualRESUMEN
PURPOSE: To determine the mutation in a Swedish family with Best disease (vitelliform macular dystrophy; VMD) and to investigate the short- and long-term effects of photodynamic treatment (PDT) on subretinal neovascularization in a young boy. METHODS: The five members of three generations of a family with VMD underwent a thorough ophthalmological examination, including best-corrected visual acuity (VA), visual field, colour vision, biomicroscopy of the posterior segment (dilated), fundus photography and electro-oculography (EOG). For the proband, an eleven-year-old boy, his father and grandfather, dark adaptation test, angiography and electroretinography (ERG) were also performed. After PCR amplification, the genotype was determined by cleavage with restriction enzyme, specific for the W93C allele. RESULTS: Four family members had an abnormal EOG response. All showed the W93C mutation in the VMD2 gene. Visual acuity ranged from 20/20 to 20/250. The fundus manifestations varied from minor pigmentary changes over egg yolk-like lesions to chorioretinal atrophy, and fluorescein angiography showed corresponding pathology. In the proband, VA decreased during follow-up from 0.5 (20/40) to 0.08 (20/250) due to a subfoveal neovascularization with haemorrhage, and PDT with visudyne was begun. The haemorrhage resolved within 2 months, and after three treatments, VA had increased to 0.25 (20/80). One year later, acuity had improved to 0.5 (20/40), and this result was stable throughout the 7 years of the follow-up. CONCLUSION: The mutation was determined to be W93C, the most common mutation in VMD in Sweden. In an eleven-year-old boy with subretinal neovascularization, PDT seemed to be beneficial also in a long-term follow-up.
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Neovascularización Coroidal/tratamiento farmacológico , Pruebas Genéticas/métodos , Fotoquimioterapia/métodos , Distrofia Macular Viteliforme/genética , Anciano , Bestrofinas , Niño , Preescolar , Canales de Cloruro/genética , Neovascularización Coroidal/etiología , Neovascularización Coroidal/genética , Electrorretinografía , Proteínas del Ojo/genética , Femenino , Angiografía con Fluoresceína , Estudios de Seguimiento , Fondo de Ojo , Humanos , Masculino , Mutación , Linaje , Factores de Tiempo , Tomografía de Coherencia Óptica , Agudeza Visual , Distrofia Macular Viteliforme/complicaciones , Distrofia Macular Viteliforme/diagnósticoRESUMEN
Population fluctuations and synchrony influence population persistence; species with larger fluctuations and more synchronised population fluctuations face higher extinction risks. Here, we analyse the effect of diet specialisation, mobility, length of the flight period, and distance to the northern edge of the species' distribution in relation to between-year population fluctuations and synchrony of butterfly species. All butterfly species associated with grasslands were surveyed over five successive years at 19 grassland sites in a forest-dominated landscape (50 km(2)) in southern Sweden. At both the local and regional level, we found larger population fluctuations in species with longer flight periods. Population fluctuations were more synchronous among localities in diet specialists. Species with a long flight period might move more to track nectar resources compared to species with shorter flight period, and if nectar sources vary widely between years and localities it may explain that population fluctuations increase with increasing flight length. Diet generalists can use different resources (in this case host plants) at different localities and this can explain the lower synchrony in population fluctuations among generalist species. Higher degree of synchrony is one possible explanation for the higher extinction risks that have been observed for more specialised species. Therefore, diet specialists are more often threatened and require more conservation efforts than generalists.
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Mariposas Diurnas/fisiología , Animales , Biodiversidad , Ecosistema , Pradera , Población , Dinámica Poblacional , Especificidad de la Especie , SueciaRESUMEN
Although solitary bees are considered to play key roles in ecosystem functions, surprisingly few studies have explored their population dynamics. We investigated the population dynamics of a rare, declining, solitary bee (Andrena humilis) in a landscape of 80 km2 in southern Sweden from 2003 to 2011. Only one population was persistent throughout all years studied; most likely this population supplied the surrounding landscape with 11 smaller, temporary local populations. Despite stable pollen availability, the size of the persistent population fluctuated dramatically in a two-year cycle over the nine years, with 490-1230 nests in odd-numbered years and 21-48 nests in even-numbered years. These fluctuations were not significantly related to climatic variables or pollen availability. Nineteen colonization and 14 extinction events were recorded. Occupancy decreased with distance from the persistent population and increased with increasing resource (pollen) availability. There were significant positive correlations between the size of the persistent population and patch occupancy and colonization. Colonizations were generally more common in patches closer to the persistent population, whereas extinctions were independent of distance from the persistent population. Our results highlight the complex population dynamics that exist for this solitary bee species, which could be due to source-sink dynamics, a prolonged diapause, or can represent a bet-hedging strategy to avoid natural enemies and survive in small habitat patches. If large fluctuations in solitary bee populations prove to be widespread, it will have important implications for interpreting ecological relationships, bee conservation, and pollination.
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Abejas/fisiología , Comportamiento de Nidificación/fisiología , Conducta Social , Animales , Clima , Dinámica Poblacional , Suecia , Factores de TiempoRESUMEN
OBJECTIVE: The aim of this study was to assess CT-colonography (CTC) in the follow-up of diverticulitis regarding patient acceptance and diagnostic accuracy for diverticular disease, adenomas and cancer, with colonoscopy as a reference standard. METHODS: A prospective comparative study where half of the patients underwent colonoscopy first, followed immediately by CTC. The other half had the examinations in the reverse order. Patient experiences and findings were registered after every examination, blinded to the examiner. RESULTS: Of a total of 110 consecutive patients, 108 were included in the study, with a median age of 56 years (range 27-84). The success rate was 91% for colonoscopy and 86% for CTC. Examination time was 25 min for both methods. The mean time for CTC evaluation was 20 min. Eighty-three per cent of the patients received sedation during colonoscopy. Despite this, patients experienced colonoscopy as more painful (p < 0.001) and uncomfortable (p < 0.001). Diverticulosis and polyps were detected in 94% and 20% with colonoscopy and in 94% and 29% with CTC, respectively. Sensitivity and specificity for CTC in the detection of diverticulosis was 99% and 67%, with a good agreement (κ = 0.71). Regarding detection of polyps, the sensitivity and specificity were 47% and 75%, with a poor agreement (κ = 0.17). No cancer was found. CONCLUSION: CTC was less painful and unpleasant and can be used for colonic investigation in the follow-up of diverticulitis. CTC detected diverticulosis with good accuracy while the detection accuracy of small polyps was poor. CTC is a viable alternative, especially in case of incomplete colonoscopy or in a situation with limited colonoscopy resources.
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Adenoma/diagnóstico por imagen , Neoplasias del Colon/diagnóstico por imagen , Colonografía Tomográfica Computarizada , Colonoscopía , Diverticulitis del Colon/diagnóstico por imagen , Aceptación de la Atención de Salud/estadística & datos numéricos , Enfermedad Aguda , Adenoma/diagnóstico , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias del Colon/diagnóstico , Diagnóstico Diferencial , Diverticulitis del Colon/diagnóstico , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Sensibilidad y Especificidad , Método Simple CiegoRESUMEN
The objective of this study was to elucidate possible reasons for the remarkable resistance of human retinal pigment epithelial (RPE) cells to oxidative stress. Much oxidative damage is due to hydrogen peroxide meeting redox-active iron in the acidic and reducing lysosomal environment, resulting in the production of toxic hydroxyl radicals that may oxidize intralysosomal content, leading to lipofuscin (LF) formation or, if more extensive, to permeabilization of lysosomal membranes. Formation of LF is a risk factor for age-related macular degeneration (AMD) and known to jeopardize normal autophagic rejuvenation of vital cellular biomolecules. Lysosomal membrane permeabilization causes release of lysosomal content (redox-active iron, lytic enzymes), which may then cause cell death. Total cellular and lysosomal low-mass iron of cultured, immortalized human RPE (ARPE-19) cells was compared to that of another professional scavenger cell line, J774, using atomic absorption spectroscopy and the cytochemical sulfide-silver method (SSM). It was found that both cell lines contained comparable levels of total as well as intralysosomal iron, suggesting that the latter is mainly kept in a non-redox-active state in ARPE-19 cells. Basal levels and capacity for upregulation of the iron-binding proteins ferritin, metallothionein and heat shock protein 70 were tested in both cell lines using immunoblotting. Compared to J774 cells, ARPE-19 cells were found to contain very high basal levels of all these proteins, which could be even further upregulated following appropriate stimulation. These findings suggest that a high basal expression of iron-binding stress proteins, which during their normal autophagic turnover in lysosomes may temporarily bind iron prior to their degradation, could contribute to the unusual oxidative stress-resistance of ARPE-19 cells. A high steady state influx of such proteins into lysosomes would keep the level of lysosomal redox-active iron permanently low. This, in turn, should delay intralysosomal accumulation of LF in RPE cells, which is known to reduce autophagic turnover as well as uptake and degradation of worn out photoreceptor tips. This may explain why severe LF accumulation and AMD normally do not develop until fairly late in life, in spite of RPE cells being continuously exposed to high levels of oxygen and light, as well as large amounts of lipid-rich material.
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Autofagia/fisiología , Proteínas de Unión a Hierro/metabolismo , Degeneración Macular/metabolismo , Estrés Oxidativo/fisiología , Epitelio Pigmentado de la Retina/metabolismo , Western Blotting , Línea Celular , Humanos , Degeneración Macular/patología , Epitelio Pigmentado de la Retina/patologíaRESUMEN
INTRODUCTION: Parastomal hernia in patients with a permanent colostomy is common. The aim of this study was to evaluate the reliability of the diagnosis based on clinical examination and to compare this examination with the result of a specially designed questionnaire and computerised tomography (CT) scan. METHODS: Forty-one patients operated upon with an abdominoperineal resection due to rectal cancer at three hospitals between 1996 and 2002 were included. At minimum of 4 years after the operation, they underwent clinical examination by two or three independent surgeons, answered a colostomy questionnaire and were offered a CT scan of the abdominal wall. RESULT: At Hospital I, 17 patients were examined by three surgeons, with inter-observer kappa values between 0.35 and 0.64. At Hospital II, 13 patients were examined by three surgeons, the kappa values ranged between 0.29 and 0.43. At Hospital III, 11 patients were examined by two surgeons, with kappa value of 0.73. The kappa value between CT scan and the colostomy questionnaire was 0.45. CONCLUSION: The inter-observer reliability was low, indicating that parastomal hernia is difficult to diagnose by patient history and clinical examination. Some herniae may not be detected by CT scan, and the correlation to patient-reported complaints is low. A more sensitive radiological method to detect parastomal hernia is needed.
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Colostomía/efectos adversos , Hernia/epidemiología , Hernia/etiología , Índice de Masa Corporal , Hernia/diagnóstico por imagen , Herniorrafia , Humanos , Variaciones Dependientes del Observador , Encuestas y Cuestionarios , Suecia/epidemiología , Tomografía Computarizada por Rayos XRESUMEN
The population dynamics of organisms living in short-lived habitats will largely depend on the turnover of habitat patches. It has been suggested that epiphytes, whose host plants can be regarded as habitat patches, often form such patch-tracking populations. However, very little is known about the long-term fate of epiphyte individuals and populations. We estimated life span and assessed environmental factors influencing changes in vitality, fertility, abundance, and distribution of the epiphytic lichen species Lobaria pulmonaria on two spatial scales, individual trees and forest patches, over a period of approximately 10 years in 66 old-growth forest fragments. The lichen had gone extinct from 7 of the 66 sites (13.0%) where it was found 10 years earlier, even though the sites remained unchanged. The risk of local population extinction increased with decreasing population size. In contrast to the decrease in the number of occupied trees and sites, the mean area of the lichen per tree increased by 43.0%. The number of trees with fertile ramets of L. pulmonaria increased from 7 (approximately 1%) to 61 (approximately 10%) trees, and the number of forest fragments with fertile ramets increased from 4 to 23 fragments. The mean annual rate of L. pulmonaria extinction at the tree level was estimated to be 2.52%, translating into an expected lifetime of 39.7 years. This disappearance rate is higher than estimated mortality rates for potential host trees. The risk of extinction at the tree level was significantly positively related to tree circumference and differed between tree species. The probability of presence of fertile ramets increased significantly with local population size. Our results show a long expected lifetime of Lobaria pulmonaria ramets on individual trees and a recent increase in vitality, probably due to decreasing air pollution. The population is, however, declining slowly even though remaining stands are left uncut, which we interpret as an extinction debt.
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Ecosistema , Extinción Biológica , Líquenes/fisiología , Árboles/fisiología , Dinámica Poblacional , Suecia , Factores de TiempoRESUMEN
H(2)DCF-DA (dihydrodichlorofluorescein diacetate) is widely used to evaluate 'cellular oxidative stress'. After passing through the plasma membrane, this lipophilic and non-fluorescent compound is de-esterified to a hydrophilic alcohol [H(2)DCF (dihydrodichlorofluorescein)] that may be oxidized to fluorescent DCF (2',7'-dichlorofluorescein) by a process usually considered to involve ROS (reactive oxygen species). It is, however, not always recognized that, being a hydrophilic molecule, H(2)DCF does not cross membranes, except for the outer fenestrated mitochondrial ones. It is also not generally realized that oxidation of H(2)DCF is dependent either on Fenton-type reactions or on unspecific enzymatic oxidation by cytochrome c, for neither superoxide, nor H(2)O(2), directly oxidizes H(2)DCF. Consequently, oxidation of H(2)DCF requires the presence of either cytochrome c or of both redox-active transition metals and H(2)O(2). Redox-active metals exist mainly within lysosomes, whereas cytochrome c resides bound to the outer side of the inner mitochondrial membrane. Following exposure to H(2)DCF-DA, weak mitochondrial fluorescence was found in both the oxidation-resistant ARPE-19 cells and the much more sensitive J774 cells. This fluorescence was only marginally enhanced following short exposure to H(2)O(2), showing that by itself it is unable to oxidize H(2)DCF. Cells that were either exposed to the lysosomotropic detergent MSDH (O-methylserine dodecylamide hydrochloride), exposed to prolonged oxidative stress, or spontaneously apoptotic showed lysosomal permeabilization and strong DCF-induced fluorescence. The results suggest that DCF-dependent fluorescence largely reflects relocation to the cytosol of lysosomal iron and/or mitochondrial cytochrome c.
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Fluoresceínas/metabolismo , Estrés Oxidativo/fisiología , Animales , Apoptosis/fisiología , Línea Celular , Citocromos c/metabolismo , Citosol/metabolismo , Fluorescencia , Humanos , Peróxido de Hidrógeno/metabolismo , Lisosomas/metabolismo , Ratones , Mitocondrias/metabolismo , Compuestos Organometálicos/metabolismo , Oxidación-Reducción , Especies Reactivas de Oxígeno/metabolismoRESUMEN
PURPOSE: To investigate the effects on near visual acuity, reading speed, central visual field and related quality of life of ranibizumab treatment of wet age-related macular degeneration (AMD). METHODS: The study was a prospective, non-comparative consecutive case series, followed for 3 months and investigator-driven. Thirty eyes of 30 patients with wet AMD were included, mean age 75 years (range 69-95 years). In addition to a full ophthalmological examination--including best-corrected visual acuity (BCVA; Early Treatment Diabetic Research Study chart), fundus biomicroscopy, fundus photography, fluorescein angiography, indocyanine green angiography (occult cases) and ocular coherence tomography--near visual acuity, reading speed, central visual field and quality of life for related activities were also investigated at baseline and at 3 months after ranibizumab treatment. RESULTS: Mean BCVA increased from 62 +/- 11 to 66 +/- 14 letters at 3 months (7%; p = 0.018). Near vision improved from 9 +/- 5 to 6 +/- 3 points (33%; p = 0.0006) and reading speed increased from 59 +/- 40 to 85 +/- 50 words/min (44%; p < 0.0001). The mean deviation from normal of the visual field improved from -9 +/- 7 to -6 +/- 5 dB (33%; p < 0.0001). Quality of life improved for distance activities from 54 +/- 28 to 63 +/- 28 points (17%; p < 0.0001) but significantly (p = 0.024) more for near activities, from 49 +/- 26 to 63 +/- 26 points (29%; p < 0.0001). Reading newspaper text in the group in which the better eye was treated showed the highest increase in quality of life score of all: 116%. CONCLUSION: The increase in BCVA after ranibizumab treatment is well established. The present study also showed significant improvements in other important visual qualities, such as near visual acuity, reading speed, central visual field and several activities influencing quality of life. The improvement was greater for near activities than for distance activities. Therefore, the beneficial effects of ranibizumab treatment shown here are more extensive than those reported previously.
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Inhibidores de la Angiogénesis/uso terapéutico , Anticuerpos Monoclonales/uso terapéutico , Calidad de Vida , Lectura , Agudeza Visual/fisiología , Campos Visuales/fisiología , Degeneración Macular Húmeda/tratamiento farmacológico , Anciano , Anciano de 80 o más Años , Anticuerpos Monoclonales Humanizados , Colorantes , Femenino , Angiografía con Fluoresceína , Humanos , Verde de Indocianina , Inyecciones , Masculino , Satisfacción del Paciente , Estudios Prospectivos , Ranibizumab , Perfil de Impacto de Enfermedad , Tomografía de Coherencia Óptica , Cuerpo Vítreo , Degeneración Macular Húmeda/fisiopatologíaRESUMEN
Currently, the habitat of many species is fragmented, resulting in small local populations with individuals occasionally dispersing between the remaining habitat patches. In a solitary bee metapopulation, extinction probability was related to both local bee population sizes and pollen resources measured as host plant population size. Patch size, on the other hand, had no additional predictive power. The turnover rate of local bee populations in 63 habitat patches over 4 years was high, with 72 extinction events and 31 colonization events, but the pollen plant population was stable with no extinctions or colonizations. Both pollen resources and bee populations had strong and independent effects on extinction probability, but connectivity was not of importance. Colonizations occurred more frequently within larger host plant populations. For metapopulation survival of the bee, large pollen plant populations are essential, independent of current bee population size.