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1.
J Dairy Sci ; 106(12): 8926-8941, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37678793

RESUMEN

The longevity of dairy cows is mainly determined by farmers' subjective culling decisions and can be linked to the environmental impact of dairy production and to the social acceptance of the industry. Still, the economic impacts of dairy cow longevity are not well understood. The aim of this study was to examine how herd average dairy cow longevity is related to the farm economic outcome. We used 3 indicators of economic outcome: technical efficiency, profitability, and average milk yield per cow. We used 2 indicators of dairy cow longevity: average herd length of life and average herd length of productive life. The study was based on a unique and detailed dataset from Swedish dairy agriculture, where herd-management data from the national dairy herd recording scheme were combined with farm-level economic variables from the Swedish Farm Accountancy Survey, for a total of 1,959 observations from 2010 to 2018. The regression results highlight that both measures of average herd dairy cow longevity have an overall positive and significant association with farm-level economic performance. These associations had an inverted U-shape, which implies that the association is first positive and then declines. Descriptive statistics indicate that the point where the maximum economic performance is attained varied across the economic indicators. Our results are relevant for individual dairy farmers and their advisors, who are interested in understanding how herd average longevity relates to economic performance on the farms. Our results are also important from a greater sustainability perspective, because linking them to previous knowledge about the environmental and social sustainability benefits of keeping cows longer highlights longevity-associated trade-offs between those benefits and the farm economic outcomes.


Asunto(s)
Industria Lechera , Longevidad , Femenino , Bovinos , Animales , Granjas , Suecia , Industria Lechera/métodos , Leche
2.
Agric Syst ; 191: 103152, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36570633

RESUMEN

Context: Resilience is the ability to deal with shocks and stresses, including the unknown and previously unimaginable, such as the Covid-19 crisis. Objective: This paper assesses (i) how different farming systems were exposed to the crisis, (ii) which resilience capacities were revealed and (iii) how resilience was enabled or constrained by the farming systems' social and institutional environment. Methods: The 11 farming systems included have been analysed since 2017. This allows a comparison of pre-Covid-19 findings and the Covid-19 crisis. Pre-Covid findings are from the SURE-Farm systematic sustainability and resilience assessment. For Covid-19 a special data collection was carried out during the early stage of lockdowns. Results and conclusions: Our case studies found limited impact of Covid-19 on the production and delivery of food and other agricultural products. This was due to either little exposure or the agile activation of robustness capacities of the farming systems in combination with an enabling institutional environment. Revealed capacities were mainly based on already existing connectedness among farmers and more broadly in value chains. Across cases, the experience of the crisis triggered reflexivity about the operation of the farming systems. Recurring topics were the need for shorter chains, more fairness towards farmers, and less dependence on migrant workers. However, actors in the farming systems and the enabling environment generally focused on the immediate issues and gave little real consideration to long-term implications and challenges. Hence, adaptive or transformative capacities were much less on display than coping capacities. The comparison with pre-Covid findings mostly showed similarities. If challenges, such as shortage of labour, already loomed before, they persisted during the crisis. Furthermore, the eminent role of resilience attributes was confirmed. In cases with high connectedness and diversity we found that these system characteristics contributed significantly to dealing with the crisis. Also the focus on coping capacities was already visible before the crisis. We are not sure yet whether the focus on short-term robustness just reflects the higher visibility and urgency of shocks compared to slow processes that undermine or threaten important system functions, or whether they betray an imbalance in resilience capacities at the expense of adaptability and transformability. Significance: Our analysis indicates that if transformations are required, e.g. to respond to concerns about transnational value chains and future pandemics from zoonosis, the transformative capacity of many farming systems needs to be actively enhanced through an enabling environment.

3.
Acta Paediatr ; 108(8): 1515-1520, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-30565294

RESUMEN

AIM: This paper presents an implementation study following previous research including a randomised controlled trial (RCT) of hospital-based home care (HBHC), referring to specialist care in a home-based setting. The aim was to evaluate whether the effects sustained when rolled out into wider practice. METHODS: In 2013-2014, 42 children newly diagnosed type 1 diabetes were included in the study at a university hospital in Sweden and followed for two years. Measurements of child safety, effects of services, resource use and service quality were included. Descriptive statistics were used to present the results and then discussed in relation to the same intervention of HBHC previously evaluated in an RCT. RESULTS: Shorter in-hospital stay was partially implemented but increased support after discharge by the diabetes nurse was not. The results indicated that the implemented HBHC was equally effective in terms of child outcomes two years from diagnosis but less effective in terms of parents' outcome. The results furthermore indicated that the quality of services decreased. CONCLUSION: The suggested overall conclusion was that the implemented HBHC services were safe but had become less effective, at least in relation to the HBHC provided under controlled circumstances.


Asunto(s)
Diabetes Mellitus Tipo 1/rehabilitación , Servicios de Atención a Domicilio Provisto por Hospital/estadística & datos numéricos , Adolescente , Adulto , Niño , Preescolar , Diabetes Mellitus Tipo 1/enfermería , Femenino , Estudios de Seguimiento , Implementación de Plan de Salud , Humanos , Masculino , Persona de Mediana Edad , Padres/psicología
4.
Neuropathol Appl Neurobiol ; 44(5): 474-490, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-28627088

RESUMEN

AIMS: Idiopathic normal pressure hydrocephalus (iNPH) is one subtype of dementia that may improve following drainage of cerebrospinal fluid (CSF). This prospective observational study explored whether expression of the water channel aquaporin-4 (AQP4) and the anchoring molecule dystrophin 71 (Dp71) are altered at astrocytic perivascular endfeet and in adjacent neuropil of iNPH patient. Observations were related to measurements of pulsatile and static intracranial pressure (ICP). METHODS: The study included iNPH patients undergoing overnight monitoring of the pulsatile/static ICP in whom a biopsy was taken from the frontal cerebral cortex during placement of the ICP sensor. Reference (Ref) biopsies were sampled from 13 patients who underwent brain surgery for epilepsy, tumours or cerebral aneurysms. The brain tissue specimens were examined by light microscopy, immunohistochemistry, densitometry and morphometry. RESULTS: iNPH patients responding to surgery (n = 44) had elevated pulsatile ICP, indicative of impaired intracranial compliance. As compared to the Ref patients, the cortical biopsies of iNPH patients revealed prominent astrogliosis and reduced expression of AQP4 and Dp71 immunoreactivities in the astrocytic perivascular endfeet and in parts of the adjacent neuropil. There was a significant correlation between degree of astrogliosis and reduction of AQP4 and Dp71 at astrocytic perivascular endfeet. CONCLUSIONS: Idiopathic normal pressure hydrocephalus patients responding to CSF diversion present with abnormal pulsatile ICP, indicative of impaired intracranial compliance. A main histopathological finding was astrogliosis and reduction of AQP4 and of Dp71 in astrocytic perivascular endfeet. We propose that the altered AQP4 and Dp71 complex contributes to the subischaemia prevalent in the brain tissue of iNPH.


Asunto(s)
Acuaporina 4/metabolismo , Distrofina/metabolismo , Gliosis/patología , Hidrocéfalo Normotenso/metabolismo , Hidrocéfalo Normotenso/patología , Anciano , Femenino , Gliosis/metabolismo , Humanos , Hidrocéfalo Normotenso/fisiopatología , Masculino , Persona de Mediana Edad
5.
Br Poult Sci ; 58(4): 337-347, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28294637

RESUMEN

1. The present study was designed first to explore the potential economic benefits of adopting management practices to reduce lameness in broiler farms, and second to explore farmers' possible perceptions of this potential in the Swedish context. The likely financial effects were addressed using a normative economic model, whereas a questionnaire-based survey was used to obtain in-depth knowledge about the perceptions of a group of broiler farmers in Sweden. 2. The three alternative practices (out of 6 tested) which realised the greatest improvements in gross margin and net return to management compared to the conventional practice were feeding whole wheat, sequential feeding and meal feeding. 3. The model showed that the negative effect of feeding whole wheat on feed conversion rate was outweighed by the effect of a low feed price and the associated decrease in feed costs. The price of wheat played a major role in the improvement of economic performance, whereas the reduction of lameness itself made a relatively minor contribution. 4. Apparently, the surveyed farmers do not recognise the potential of the positive effects of changing feed or feeding practices on both broiler welfare and farm economics although their implementation can be of great importance in the broiler sector where profit margins are very tight.​.


Asunto(s)
Crianza de Animales Domésticos/economía , Actitud , Pollos , Cojera Animal/prevención & control , Enfermedades de las Aves de Corral/prevención & control , Adulto , Bienestar del Animal/economía , Animales , Femenino , Humanos , Cojera Animal/economía , Masculino , Persona de Mediana Edad , Modelos Económicos , Enfermedades de las Aves de Corral/economía , Encuestas y Cuestionarios , Suecia
6.
J Dairy Sci ; 99(1): 579-92, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26547638

RESUMEN

In this study, we sought to identify empirically the types of use and non-use values that motivate dairy farmers in their work relating to animal welfare of dairy cows. We also sought to identify how they prioritize between these use and non-use values. Use values are derived from productivity considerations; non-use values are derived from the wellbeing of the animals, independent of the present or future use the farmer may make of the animal. In particular, we examined the empirical content and structure of the economic value dairy farmers associate with animal welfare of dairy cows. Based on a best-worst scaling approach and data from 123 Swedish dairy farmers, we suggest that the economic value those farmers associate with animal welfare of dairy cows covers aspects of both use and non-use type, with non-use values appearing more important. Using principal component factor analysis, we were able to check unidimensionality of the economic value construct. These findings are useful for understanding why dairy farmers may be interested in considering dairy cow welfare. Such understanding is essential for improving agricultural policy and advice aimed at encouraging dairy farmers to improve animal welfare; communicating to consumers the values under which dairy products are produced; and providing a basis for more realistic assumptions when developing economic models about dairy farmers' behavior.


Asunto(s)
Bienestar del Animal/economía , Actitud , Bovinos/fisiología , Industria Lechera/economía , Agricultores/psicología , Crianza de Animales Domésticos , Animales , Femenino , Modelos Económicos , Motivación , Análisis de Componente Principal
7.
Animal ; 17(10): 100971, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37734363

RESUMEN

Farm animal health is an area of increasing interest to both the public and industry stakeholders. There is an ongoing debate on whether improving animal health, and thereby increasing welfare, is profitable or not. Improving animal health often requires investments in the farm or increases labour costs. As a result, the impact of animal health on farm economy is particularly interesting. This study systematically maps and assesses the available evidence in the published scientific literature regarding the link between farms' economic outcomes on dairy cow health, with the aim of identifying knowledge gaps in this field of research. In total, 59 peer-reviewed articles were included using a broad range of animal health variables and economic outcomes. We found a heterogeneous body of evidence in terms of both methods, animal health measures (AHMs) and economic outcome measures used. None of the included studies makes explicit causal claims between AHMs and economic outcomes. The results suggest that common production diseases such as clinical mastitis and lameness, which are painful and affect cow health and welfare, are costly for farmers. We found a knowledge gap and lack of evidence on the impact of animal health interventions on farms' economic outcomes, as well as the long-term effects of such interventions. Future research should aim to investigate the causal links between animal health and economic outcomes.

8.
Paediatr Neonatal Pain ; 5(4): 99-109, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38149216

RESUMEN

It is often a challenge for a child to communicate their pain, and their possibilities to do so should be strengthened in healthcare settings. Digital self-assessment provides a potential solution for person-centered care in pain management and promotes child participation when a child is ill. A child's perception of pain assessment differs when it is assessed using digital or analog formats. As we move into the digital era, there is an urgent need to validate digital pain assessment tools, including the newly developed electronic Faces Thermometer Scale (eFTS). This study protocol describes three studies with the overall aim to evaluate psychometric properties of the eFTS for assessing pain in children 8-17 years of age. A multi-site project design combining quantitative and qualitative methods will be used for three observational studies. Study 1: 100 Swedish-speaking children will report the level of anticipated pain from vignettes describing painful situations in four levels of pain and a think-aloud method will be used for data collection. Data will be analyzed with phenomenography as well as descriptive and comparative statistics. Study 2: 600 children aged 8-17 years at pediatric and dental settings in Sweden, Denmark, Iceland, and USA will be included. Children will assess their pain intensity due to medical or dental procedures, surgery, or acute pain using three different pain Scales for each time point; the eFTS, the Faces Pain Scale Revised, and the Coloured Analogue Scale. Descriptive and comparative statistics will be used, with subanalysis taking cultural context into consideration. Study 3: A subgroup of 20 children out of these 600 children will be purposely included in an interview to describe experiences of grading their own pain using the eFTS. Qualitative data will be analyzed with content analysis. Our pilot studies showed high level of adherence to the study procedure and rendered only a small revision of background questionnaires. Preliminary analysis indicated that the instruments are adequate to be used by children and that the analysis plan is feasible. A digital pain assessment tool contributes to an increase in pain assessment in pediatric care. The Medical Research Council framework for complex interventions in healthcare supports a thorough development of a new scale. By evaluating psychometric properties in several settings by both qualitative and quantitative methods, the eFTS will become a well-validated tool to strengthen the child's voice within healthcare.

9.
Eur J Cancer Care (Engl) ; 21(1): 59-66, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21848580

RESUMEN

The study aims to describe the experiences of a hospital-based home care programme in the families of children with cancer. Fourteen parents, representing 10 families, were interviewed about their experiences of a hospital-based home care programme during a 4-month period in 2009 at a university hospital in Denmark. Five children participated in all or part of the interview. The interviews were transcribed verbatim and analysed using qualitative content analysis. The findings indicate that hospital-based home care enabled the families to remain intact throughout the course of treatment, as it decreased the strain on the family and the ill child, maintained normality and an ordinary everyday life and fulfilled the need for safety and security. According to family members of children with cancer, hospital-based home care support enhanced their quality of life during the child's cancer trajectory. Our study highlights the importance of providing hospital-based home care with consideration for the family members' need for the sense of security achieved by home care by experienced paediatric oncology nurses and regular contact with the doctor. In future studies, interviews with children and siblings could be an important source of information for planning and delivering care suited to the families' perceived needs.


Asunto(s)
Servicios de Salud del Niño/normas , Familia/psicología , Servicios de Atención a Domicilio Provisto por Hospital/normas , Neoplasias/terapia , Calidad de la Atención de Salud/normas , Adolescente , Adulto , Niño , Servicios de Salud del Niño/organización & administración , Preescolar , Dinamarca , Femenino , Humanos , Lactante , Masculino , Persona de Mediana Edad , Neoplasias/psicología , Encuestas y Cuestionarios
10.
Lett Appl Microbiol ; 53(1): 73-8, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21535044

RESUMEN

AIM: Testing the ability of the alternative ethanol production yeast Dekkera bruxellensis to produce ethanol from lignocellulose hydrolysate and comparing it to Saccharomyces cerevisiae. METHODS AND RESULTS: Industrial isolates of D. bruxellensis and S. cerevisiae were cultivated in small-scale batch fermentations of enzymatically hydrolysed steam exploded aspen sawdust. Different dilutions of hydrolysate were tested. None of the yeasts grew in undiluted or 1:2 diluted hydrolysate [final glucose concentration always adjusted to 40 g l⁻¹ (0.22 mol l⁻¹)]. This was most likely due to the presence of inhibitors such as acetate or furfural. In 1:5 hydrolysate, S. cerevisiae grew, but not D. bruxellensis, and in 1:10 hydrolysate, both yeasts grew. An external vitamin source (e.g. yeast extract) was essential for growth of D. bruxellensis in this lignocellulosic hydrolysate and strongly stimulated S. cerevisiae growth and ethanol production. Ethanol yields of 0.42 ± 0.01 g ethanol (g glucose)⁻¹ were observed for both yeasts in 1:10 hydrolysate. In small-scale continuous cultures with cell recirculation, with a gradual increase in the hydrolysate concentration, D. bruxellensis was able to grow in 1:5 hydrolysate. In bioreactor experiments with cell recirculation, hydrolysate contents were increased up to 1:2 hydrolysate, without significant losses in ethanol yields for both yeasts and only slight differences in viable cell counts, indicating an ability of both yeasts to adapt to toxic compounds in the hydrolysate. CONCLUSIONS: Dekkera bruxellensis and S. cerevisiae have a similar potential to ferment lignocellulose hydrolysate to ethanol and to adapt to fermentation inhibitors in the hydrolysate. SIGNIFICANCE AND IMPACT OF THE STUDY: This is the first study investigating the potential of D. bruxellensis to ferment lignocellulosic hydrolysate. Its high competitiveness in industrial fermentations makes D. bruxellensis an interesting alternative for ethanol production from those substrates.


Asunto(s)
Biocombustibles , Dekkera/metabolismo , Etanol , Microbiología Industrial , Lignina/metabolismo , Saccharomyces cerevisiae/metabolismo , Reactores Biológicos , Fermentación , Hidrólisis , Saccharomyces cerevisiae/crecimiento & desarrollo
11.
J Cell Biol ; 47(2): 319-31, 1970 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-19866734

RESUMEN

Freehand, isolated neuronal perikarya from the hypoglossal nucleus of the rabbit have been examined with light-and electron-microscopy (transmission and scanning). The surface of the cell bodies was largely covered with spherical particles which were 0.5-2 micro in diameter. Transmission electron microscopy proved that the spherical particles were synaptic nerve terminals. Crush of the hypoglossal nerve which leads to chromatolysis and swelling of the neuronal cell bodies results in a conspicuous reduction in the number of terminals attached to the surface of hypoglossal neurons. This effect was observed both for isolated neurons and in tissue sections. The effect is considered in relation to earlier reported variations in the adherence of neuropil to isolated neuronal perikarya. The functional importance of nerve ending detachment in connection with nerve injury is discussed.

12.
J Cell Biol ; 53(3): 654-61, 1972 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-4402165

RESUMEN

A bulk fraction enriched with respect to neuronal cell bodies was used as starting material for the isolation of neuronal plasma membrane The cells were gently homogenized in isotonic sucrose and a crude membrane containing fraction sedimented at 3000 g. Subsequently, the membrane fraction was purified on a discontinuous sucrose density gradient between 35% and 25 5% sucrose (w/w). Enzymatic analyses showed a 4-5-fold enrichment in plasma membrane markers, and a 10-15% contamination of mitochondrial and microsomal material. Electron micrographs of the membrane fraction confirmed the enzymatic data Fragmented membranes were found, mainly in vesicular form No ribosomes, but a few mitochondria and some multilamellar membranes were seen


Asunto(s)
Membrana Celular , Neuronas/citología , Adenosina Trifosfatasas/análisis , Animales , Fraccionamiento Celular , Membrana Celular/enzimología , Nucléolo Celular , Núcleo Celular , Centrifugación por Gradiente de Densidad , Corteza Cerebral/citología , Corteza Cerebral/enzimología , Citocromos , Complejo IV de Transporte de Electrones/análisis , Glucofosfatos/análisis , Métodos , Microscopía Electrónica , Microsomas/enzimología , Mitocondrias/enzimología , Monoaminooxidasa/análisis , NADP , Neuronas/enzimología , Oxidorreductasas/análisis , Conejos , Sacarosa
13.
Animal ; 12(10): 2147-2155, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-29362012

RESUMEN

This study explored how farmers' motivation in terms of use values and/or non-use values to work with farm animal welfare are associated with the economic outcome for the farm. Use values in farm animal welfare refer to economic value derived from productivity and profitability considerations. Non-use values in farm animal welfare refer to economic value derived from good animal welfare, irrespective of the use the farmer derives from the animal, currently or in the future. The analysis was based on detailed information about the income statements of a sample of Swedish dairy farmers, obtained from the Swedish Farm Economic Survey, complemented with survey information about their perceived use and non-use values in farm animal welfare. The findings suggest that farm economic outcome is significantly associated with motivation in terms of use values, but not so much with motivation in terms of non-use values. This is interesting from a policy point of view, because it indicates that farmers with different approaches to farm animal welfare may experience different economic outcomes for their farms. Findings can, for instance, be used to strengthen farmers' engagement in various private quality assurance standards, which generally focus on values of non-use type, by pointing to that realisation of such values will not impair the economic outcome of the farms. Moreover, findings also suggest that farmers' economic incentives for engagement in such standards may need to be further strengthened in order to become more attractive, as findings point to that a focus on non-use values generally is not associated with more favourable economic outcomes.


Asunto(s)
Bienestar del Animal , Industria Lechera , Animales , Animales Domésticos , Granjas , Suecia
14.
Sci Rep ; 8(1): 1482, 2018 01 24.
Artículo en Inglés | MEDLINE | ID: mdl-29367716

RESUMEN

The formation of new atmospheric particles involves an initial step forming stable clusters less than a nanometre in size (<~1 nm), followed by growth into quasi-stable aerosol particles a few nanometres (~1-10 nm) and larger (>~10 nm). Although at times, the same species can be responsible for both processes, it is thought that more generally each step comprises differing chemical contributors. Here, we present a novel analysis of measurements from a unique multi-station ground-based observing system which reveals new insights into continental-scale patterns associated with new particle formation. Statistical cluster analysis of this unique 2-year multi-station dataset comprising size distribution and chemical composition reveals that across Europe, there are different major seasonal trends depending on geographical location, concomitant with diversity in nucleating species while it seems that the growth phase is dominated by organic aerosol formation. The diversity and seasonality of these events requires an advanced observing system to elucidate the key processes and species driving particle formation, along with detecting continental scale changes in aerosol formation into the future.

15.
Vet Comp Orthop Traumatol ; 20(1): 12-7, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17364090

RESUMEN

Degenerative and reactive structural alterations occurring after experimentally-induced disc degeneration were evaluated using a porcine model. A cranial perforation was made through the L4 vertebral endplate into the nucleus pulposus. Three months later, the lumbar intervertebral disc and adjacent vertebrae were dissected, fixed in formalin and further processed for histopathological analyses. The results showed that there were nucleus pulposus fragments, rather than a distinct border between the nucleus and annulus fibrosus. The central lamellae were distorted and delamination of the outer anterior layers was observed. Blood vessels emerged from the adjacent tissue, penetrated the annulus and branched into the residues of the nucleus. Nerve fibres accompanying the blood vessels could be recognized in the disc within the connective scar tissue. The epiphyseal cartilage plates in the vertebrae were hypertrophic in several areas and there was bone formation directed towards the centre of the vertebral body and the disc. Hypertrophic hyaline cartilage, newly formed bone and scar tissue filled the injury canal. A slight chronic inflammatory reaction was evident along vascular buds. The reactive changes dominated over the degenerated features in the operated disc. Physiological loading enhanced the infiltration of various tissue types characterizing immature cartilage formation. Prominent neovascularisation of the central parts of the disc is likely to be of key importance in turning the degenerative features of the remaining tissue into reactive healthy structures.


Asunto(s)
Modelos Animales de Enfermedad , Desplazamiento del Disco Intervertebral/fisiopatología , Vértebras Lumbares/lesiones , Fracturas de Salter-Harris , Traumatismos Vertebrales/fisiopatología , Animales , Placa de Crecimiento/fisiopatología , Humanos , Disco Intervertebral/irrigación sanguínea , Vértebras Lumbares/fisiopatología , Masculino , Neovascularización Fisiológica , Porcinos
16.
Sci Rep ; 7(1): 3318, 2017 06 12.
Artículo en Inglés | MEDLINE | ID: mdl-28607400

RESUMEN

Atmospheric new particle formation (NPF) and growth significantly influences climate by supplying new seeds for cloud condensation and brightness. Currently, there is a lack of understanding of whether and how marine biota emissions affect aerosol-cloud-climate interactions in the Arctic. Here, the aerosol population was categorised via cluster analysis of aerosol size distributions taken at Mt Zeppelin (Svalbard) during a 11 year record. The daily temporal occurrence of NPF events likely caused by nucleation in the polar marine boundary layer was quantified annually as 18%, with a peak of 51% during summer months. Air mass trajectory analysis and atmospheric nitrogen and sulphur tracers link these frequent nucleation events to biogenic precursors released by open water and melting sea ice regions. The occurrence of such events across a full decade was anti-correlated with sea ice extent. New particles originating from open water and open pack ice increased the cloud condensation nuclei concentration background by at least ca. 20%, supporting a marine biosphere-climate link through sea ice melt and low altitude clouds that may have contributed to accelerate Arctic warming. Our results prompt a better representation of biogenic aerosol sources in Arctic climate models.

17.
Mucosal Immunol ; 9(1): 171-82, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26080709

RESUMEN

Disruption of the homeostatic balance of intestinal dendritic cells (DCs) and macrophages (MQs) may contribute to inflammatory bowel disease. We characterized DC and MQ populations, including their ability to produce retinoic acid, in clinical material encompassing Crohn's ileitis, Crohn's colitis and ulcerative colitis (UC) as well as mesenteric lymph nodes (MLNs) draining these sites. Increased CD14(+)DR(int) MQs characterized inflamed intestinal mucosa while total CD141(+) or CD1c(+) DCs numbers were unchanged. However, CD103(+) DCs, including CD141(+)CD103(+) and CD1c(+)CD103(+) DCs, were reduced in inflamed intestine. In MLNs, two CD14(-) DC populations were identified: CD11c(int)HLADR(hi) and CD11c(hi)HLADR(int) cells. A marked increase of CD11c(hi)HLADR(int) DC, particularly DR(int)CD1c(+) DCs, characterized MLNs draining inflamed intestine. The fraction of DC and MQ populations expressing aldehyde dehydrogenase (ALDH) activity, reflecting retinoic acid synthesis, in UC colon, both in active disease and remission, were reduced compared to controls and inflamed Crohn's colon. In contrast, no difference in the frequency of ALDH(+) cells among blood precursors was detected between UC patients and non-inflamed controls. This suggests that ALDH activity in myeloid cells in the colon of UC patients, regardless of whether the disease is active or in remission, is influenced by the intestinal environment.


Asunto(s)
Aldehído Deshidrogenasa/inmunología , Colitis Ulcerosa/inmunología , Colon/inmunología , Enfermedad de Crohn/inmunología , Células Dendríticas/inmunología , Macrófagos/inmunología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Aldehído Deshidrogenasa/genética , Antígenos CD/genética , Antígenos CD/inmunología , Antígenos CD1/genética , Antígenos CD1/inmunología , Antígenos de Superficie/genética , Antígenos de Superficie/inmunología , Antígeno CD11c/genética , Antígeno CD11c/inmunología , Estudios de Casos y Controles , Colitis Ulcerosa/genética , Colitis Ulcerosa/patología , Colon/patología , Enfermedad de Crohn/genética , Enfermedad de Crohn/patología , Células Dendríticas/patología , Femenino , Regulación de la Expresión Génica , Glicoproteínas/genética , Glicoproteínas/inmunología , Antígenos HLA-DR/genética , Antígenos HLA-DR/inmunología , Humanos , Cadenas alfa de Integrinas/genética , Cadenas alfa de Integrinas/inmunología , Mucosa Intestinal/inmunología , Mucosa Intestinal/patología , Receptores de Lipopolisacáridos/genética , Receptores de Lipopolisacáridos/inmunología , Ganglios Linfáticos/inmunología , Ganglios Linfáticos/patología , Macrófagos/patología , Masculino , Persona de Mediana Edad , Índice de Severidad de la Enfermedad , Transducción de Señal , Trombomodulina
18.
J Mol Biol ; 276(4): 775-86, 1998 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-9500918

RESUMEN

We used isothermal titration calorimetry and fluorescence spectroscopy to investigate the thermodynamics of non-sequence-specific DNA-binding by the Sso7d protein from the archaeon Sulfolobus solfataricus. We report the Sso7d-poly(dGdC) binding thermodynamics as a function of buffer composition (Tris-HCl or phosphate), temperature (15 to 45 degrees C), pH (7.1 to 8.0), osmotic stress and solvent (H2O/2H2O), and compare it to poly (dAdT) binding; and we have previously also reported the salt concentration dependence. Binding isotherms can be represented by the McGhee-von Hippel model for non-cooperative binding, with a binding site size of four to five DNA base-pairs and binding free energies in the range DeltaG degrees approximately -7 to DeltaG degrees approximately -10 kcal mol-1, depending on experimental conditions. The non-specific nature of the binding is reflected in similar thermodynamics for binding to poly(dAdT) and poly(dGdC). The native lysine methylation of Sso7d has only minor effects on the binding thermodynamics. Sso7d binding to poly(dGdC) is endothermic at 25 degrees C with a binding enthalpy DeltaH degrees approximately 10 kcal mol-1 in both phosphate and Tris-HCl buffers at pH 7.6, indicating that DeltaH degrees does not include large contributions from coupled buffer ionization equilibria at this pH. The binding enthalpy is temperature dependent with a measured heat capacity change DeltaCp degrees=-0.25(+/-0.01) kcal mol-1 K-1 and extrapolations of thermodynamic data indicate that the complex is heat stable with exothermic binding close to the growth temperature (75 to 80 degreesC) of S. solfataricus. Addition of neutral solutes (osmotic stress) has minor effects on DeltaG degrees and the exchange of H2O for 2H2O has only a small effect on DeltaH degrees, consistent with the inference that complex formation is not accompanied by net changes in surface hydration. Thus, other mechanisms for the heat capacity change must be found. The observed thermodynamics is discussed in relation to the nature of non-sequence-specific DNA-binding by proteins.


Asunto(s)
Proteínas Arqueales/metabolismo , ADN de Archaea/metabolismo , Proteínas de Unión al ADN/metabolismo , Sulfolobus/metabolismo , Proteínas Arqueales/química , Secuencia de Bases , Sitios de Unión , Calorimetría , ADN de Archaea/química , Proteínas de Unión al ADN/química , Óxido de Deuterio/metabolismo , Concentración de Iones de Hidrógeno , Lisina/química , Sustancias Macromoleculares , Metilación , Presión Osmótica , Poli dA-dT/química , Poli dA-dT/metabolismo , Polidesoxirribonucleótidos/química , Polidesoxirribonucleótidos/metabolismo , Unión Proteica , Espectrometría de Fluorescencia , Temperatura , Termodinámica , Agua/metabolismo
19.
Mucosal Immunol ; 8(3): 545-58, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25269704

RESUMEN

Mucosal tissues contain large numbers of memory CD4(+) T cells that, through T-cell receptor-dependent interactions with antigen-presenting cells, are believed to have a key role in barrier defense and maintenance of tissue integrity. Here we identify a major subset of memory CD4(+) T cells at barrier surfaces that coexpress interleukin-18 receptor alpha (IL-18Rα) and death receptor-3 (DR3), and display innate lymphocyte functionality. The cytokines IL-15 or the DR3 ligand tumor necrosis factor (TNF)-like cytokine 1A (TL1a) induced memory IL-18Rα(+)DR3(+)CD4(+) T cells to produce interferon-γ, TNF-α, IL-6, IL-5, IL-13, granulocyte-macrophage colony-stimulating factor (GM-CSF), and IL-22 in the presence of IL-12/IL-18. TL1a synergized with IL-15 to enhance this response, while suppressing IL-15-induced IL-10 production. TL1a- and IL-15-mediated cytokine induction required the presence of IL-18, whereas induction of IL-5, IL-13, GM-CSF, and IL-22 was IL-12 independent. IL-18Rα(+)DR3(+)CD4(+) T cells with similar functionality were present in human skin, nasal polyps, and, in particular, the intestine, where in chronic inflammation they localized with IL-18-producing cells in lymphoid aggregates. Collectively, these results suggest that human memory IL-18Rα(+)DR3(+) CD4(+) T cells may contribute to antigen-independent innate responses at barrier surfaces.


Asunto(s)
Linfocitos T CD4-Positivos/inmunología , Enfermedad de Crohn/inmunología , Inmunidad Innata , Pólipos Nasales/inmunología , Receptores de Interleucina-18/inmunología , Miembro 25 de Receptores de Factores de Necrosis Tumoral/inmunología , Linfocitos T CD4-Positivos/patología , Enfermedad de Crohn/genética , Enfermedad de Crohn/patología , Células Epiteliales/inmunología , Células Epiteliales/patología , Regulación de la Expresión Génica , Factor Estimulante de Colonias de Granulocitos y Macrófagos/genética , Factor Estimulante de Colonias de Granulocitos y Macrófagos/inmunología , Humanos , Inmunidad Mucosa , Memoria Inmunológica , Interferón gamma/genética , Interferón gamma/inmunología , Interleucina-13/genética , Interleucina-13/inmunología , Interleucina-15/genética , Interleucina-15/inmunología , Interleucina-5/genética , Interleucina-5/inmunología , Interleucina-6/genética , Interleucina-6/inmunología , Interleucinas/genética , Interleucinas/inmunología , Mucosa Intestinal/inmunología , Mucosa Intestinal/patología , Pólipos Nasales/genética , Pólipos Nasales/patología , Cultivo Primario de Células , Receptores de Interleucina-18/genética , Miembro 25 de Receptores de Factores de Necrosis Tumoral/genética , Transducción de Señal , Piel/citología , Piel/inmunología , Miembro 15 de la Superfamilia de Ligandos de Factores de Necrosis Tumoral/genética , Miembro 15 de la Superfamilia de Ligandos de Factores de Necrosis Tumoral/inmunología , Factor de Necrosis Tumoral alfa/genética , Factor de Necrosis Tumoral alfa/inmunología , Interleucina-22
20.
Eur J Cell Biol ; 46(3): 470-7, 1988 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-3181166

RESUMEN

Electron microscopic immunocytochemistry, in conjunction with the immunogold technique, was used to demonstrate the ultrastructural localization of thioredoxin and thioredoxin reductase in rat liver hepatocytes. Gold particles representing thioredoxin and thioredoxin reductase antigenic sites were found throughout the cell, but particularly densely associated with the granular endoplasmic reticulum and the cisternae of the Golgi complex. Label was also distributed over the cytosol and in the chromatin of the nucleus. We conclude that thioredoxin and thioredoxin reductase are present in several different cellular compartments including the nucleus. In particular, the enrichment of thioredoxin and thioredoxin reductase to the endoplasmic reticulum is consistent with functions in protein processing, secretion and the formation of nascent protein disulfides.


Asunto(s)
Proteínas Bacterianas/análisis , Hígado/análisis , NADH NADPH Oxidorreductasas/análisis , Reductasa de Tiorredoxina-Disulfuro/análisis , Tiorredoxinas/análisis , Animales , Núcleo Celular/análisis , Núcleo Celular/ultraestructura , Citoplasma/análisis , Citoplasma/ultraestructura , Inmunohistoquímica , Hígado/ultraestructura , Masculino , Microscopía Electrónica , Ratas , Ratas Endogámicas , Tiorredoxinas/ultraestructura
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