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2.
EJVES Vasc Forum ; 58: 5-10, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36569522

RESUMO

Objective: Acute tissue ischaemia may arise due to arterial emergencies or during more complex vascular procedures and may be mitigated by temporary shunting techniques.Endovascular shunting (ES) techniques enable percutaneous access and shunting from the donor artery without the need to completely interrupt the arterial flow in the donor artery. An endoshunt system may also cover longer distances than most conventional shunts. The aim was to investigate and optimise the flow rates in different endovascular shunt systems. Methods: Step 1: The flow capacity of different ES configurations was compared with the flow capacity of a 9 Fr Pruitt-Inahara shunt (PIS). An intravenous bag with 0.9% NaCl, pressurised to 90 mmHg, was connected simultaneously to a PIS and to one of the tested ES configurations. The two shunt systems were then opened at the same time.The delivered fluid volumes from the shunt systems were collected and measured. The volume flow rate was subsequently calculated.Steps 2 and 3: Within a heart lung machine circuit, pressure-flow charts were constructed for the individual ES components and for the fully connected optimised endoshunt systems. The flow rate was increased in steps of 40-50 mL/min while monitoring the driving pressure, enabling the creation and comparison of the pressure-flow charts for the individually tested components. In total, seven individual inflow and outflow potential ES components were investigated with inflow and outflow diameters ranging from 6 to 15 Fr. Results: ES systems based on standard donor introducers led to substantially lower volume flow than the corresponding PIS volume flow, whereas ES systems based on dedicated 6 or 8 Fr dialysis access introducers (Prelude Short Sheet, Merit Medical) matched PIS flow rates. The introduction of 30 cm long »'' perfusion tubing within the ES system did not affect volume flow for any of the tested ES configurations. Conclusion: Endoshunting techniques can match PIS volume flow rates over short and long distances. The achieved ES flow rate is highly dependent on the components used within the ES system.

3.
J Endocr Soc ; 6(6): bvac045, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35480633

RESUMO

Context: Whether biochemical remission normalizes life expectancy in Cushing's disease (CD) patients remains unclear. Previous studies evaluating mortality in CD are limited by using the expected number of deaths in the background population instead of the actual number in matched controls. Objective and setting: To study mortality by time-to-event analysis in an unselected nationwide CD patient cohort. Design and participants: Longitudinal data from the Swedish Pituitary Register of 371 patients diagnosed with CD from 1991 to 2018 and information from the Swedish Cause of Death Register were evaluated. Four controls per patient (n = 1484) matched at the diagnosis date by age, sex, and residential area were included. Main outcome measures: Mortality and causes of death. Results: The median diagnosis age was 44 years (interquartile range 32-56), and the median follow-up was 10.6 years (5.7-18.0). At the 1-, 5-, 10-, 15-, and 20-year follow-ups, the remission rates were 80%, 92%, 96%, 91%, and 97%, respectively. Overall mortality was increased in CD patients compared with matched controls [hazard ratio (HR) 2.1 (95% CI 1.5-2.8)]. The HRs were 1.5 (1.02-2.2) for patients in remission at the last follow-up (n = 303), 1.7 (1.03-2.8) for those in remission after a single pituitary surgery (n = 177), and 5.6 (2.7-11.6) for those not in remission (n = 31). Cardiovascular diseases (32/66) and infections (12/66) were overrepresented causes of death. Conclusions: Mortality was increased in CD patients despite biochemical remission compared to matched controls. The study highlights the importance of careful comorbidity monitoring, regardless of remission status.

4.
J Clin Endocrinol Metab ; 106(6): 1750-1760, 2021 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-33567076

RESUMO

CONTEXT: Psychiatric symptoms are common in Cushing's disease (CD) and seem only partly reversible following treatment. OBJECTIVE: To investigate drug dispenses associated to psychiatric morbidity in CD patients before treatment and during long-term follow-up. DESIGN: Nationwide longitudinal register-based study. SETTING: University Hospitals in Sweden. SUBJECTS: CD patients diagnosed between 1990 and 2018 (N = 372) were identified in the Swedish Pituitary Register. Longitudinal data was collected from 5 years before, at diagnosis, and during follow-up. Four matched controls per patient were included. Cross-sectional subgroup analysis of 76 patients in sustained remission was also performed. MAIN OUTCOME MEASURES: Data from the Swedish Prescribed Drug Register and the Patient Register. RESULTS: In the 5-year period before and at diagnosis, use of antidepressants (odds ratio [OR] 2.2 [95% confidence interval (CI) 1.3-3.7]) and 2.3 [1.6-3.5]), anxiolytics [2.9 (1.6-5.3) and 3.9 (2.3-6.6)], and sleeping pills [2.1 (1.2-3.7) and 3.8 (2.4-5.9)] was more common in CD than controls. ORs remained elevated at 5-year follow-up for antidepressants [2.4 (1.5-3.9)] and sleeping pills [3.1 (1.9-5.3)]. Proportions of CD patients using antidepressants (26%) and sleeping pills (22%) were unchanged at diagnosis and 5-year follow-up, whereas drugs for hypertension and diabetes decreased. Patients in sustained remission for median 9.3 years (interquartile range 8.1-10.4) had higher use of antidepressants [OR 2.0 (1.1-3.8)] and sleeping pills [2.4 (1.3-4.7)], but not of drugs for hypertension. CONCLUSIONS: Increased use of psychotropic drugs in CD was observed before diagnosis and remained elevated regardless of remission status, suggesting persisting negative effects on mental health. The study highlights the importance of early diagnosis of CD, and the need for long-term monitoring of mental health.


Assuntos
Transtornos Mentais/tratamento farmacológico , Hipersecreção Hipofisária de ACTH/epidemiologia , Psicotrópicos/uso terapêutico , Adulto , Estudos Transversais , Feminino , Seguimentos , Humanos , Estudos Longitudinais , Masculino , Transtornos Mentais/epidemiologia , Transtornos Mentais/etiologia , Pessoa de Meia-Idade , Morbidade , Hipersecreção Hipofisária de ACTH/complicações , Hipersecreção Hipofisária de ACTH/diagnóstico , Hipersecreção Hipofisária de ACTH/tratamento farmacológico , Estudos Retrospectivos , Suécia/epidemiologia
5.
J Clin Endocrinol Metab ; 106(4): 1183-1194, 2021 03 25.
Artigo em Inglês | MEDLINE | ID: mdl-33106857

RESUMO

CONTEXT: Aggressive pituitary tumors (APTs) are characterized by unusually rapid growth and lack of response to standard treatment. About 1% to 2% develop metastases being classified as pituitary carcinomas (PCs). For unknown reasons, the corticotroph tumors are overrepresented among APTs and PCs. Mutations in the alpha thalassemia/mental retardation syndrome X-linked (ATRX) gene, regulating chromatin remodeling and telomere maintenance, have been implicated in the development of several cancer types, including neuroendocrine tumors. OBJECTIVE: To study ATRX protein expression and mutational status of the ATRX gene in APTs and PCs. DESIGN: We investigated ATRX protein expression by using immunohistochemistry in 30 APTs and 18 PCs, mostly of Pit-1 and T-Pit cell lineage. In tumors lacking ATRX immunolabeling, mutational status of the ATRX gene was explored. RESULTS: Nine of the 48 tumors (19%) demonstrated lack of ATRX immunolabelling with a higher proportion in patients with PCs (5/18; 28%) than in those with APTs (4/30;13%). Lack of ATRX was most common in the corticotroph tumors, 7/22 (32%), versus tumors of the Pit-1 lineage, 2/24 (8%). Loss-of-function ATRX mutations were found in all 9 ATRX immunonegative cases: nonsense mutations (n = 4), frameshift deletions (n = 4), and large deletions affecting 22-28 of the 36 exons (n = 3). More than 1 ATRX gene defect was identified in 2 PCs. CONCLUSION: ATRX mutations occur in a subset of APTs and are more common in corticotroph tumors. The findings provide a rationale for performing ATRX immunohistochemistry to identify patients at risk of developing aggressive and potentially metastatic pituitary tumors.


Assuntos
Adenoma Hipofisário Secretor de ACT/genética , Adenoma/genética , Carcinoma/genética , Neoplasias Hipofisárias/genética , Proteína Nuclear Ligada ao X/genética , Adenoma Hipofisário Secretor de ACT/epidemiologia , Adenoma Hipofisário Secretor de ACT/patologia , Adenoma/epidemiologia , Adenoma/patologia , Adolescente , Adulto , Idoso , Carcinoma/epidemiologia , Carcinoma/patologia , Estudos de Coortes , Corticotrofos/metabolismo , Corticotrofos/patologia , Europa (Continente)/epidemiologia , Feminino , Frequência do Gene , Predisposição Genética para Doença , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Invasividade Neoplásica/genética , Neoplasias Hipofisárias/epidemiologia , Neoplasias Hipofisárias/patologia , Adulto Jovem
6.
Infect Dis (Lond) ; 50(10): 736-742, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29688098

RESUMO

BACKGROUND: Previous studies have identified patients infected with Mycobacterium chimaera (M. chimaera) subsequent to cardiac surgery. Water tanks in heater-cooler units (HCUs) used cardiac heart surgery was traced as source. The aim was to investigate occurrence of M. chimaera and other microorganisms in HCUs and evaluate the silver-ion cleaning routine. METHOD: Five HCUs were disinfected with silver-ions and examined for mycobacteria directly (15 min) after the disinfection procedures and later on three occasions (3, 6, 10 weeks). One HCU was selected for additional investigation of the presence of other microorganisms. In addition, tap water from five sinks in the surgical department was examined for the presence of mycobacteria and other microorganisms. RESULTS: M. chimaera grew in all the HCU water tanks and in 35 of the 40 HCU samples. Three of the samples also contained Mycobacterium gordonae. When the selected HCU tanks were analysed directly after the disinfection procedure bacteria and fungi were found but no non-fermenting Gram-negative rods. These HCU samples contained a doubled to 3 fold amount of bacteria compared to initial tap water samples. No mycobacteria were found in any sample from the five water taps. CONCLUSION: The silver-ion cleaning routine was insufficient and M. chimaera was found in all HCUs. However, no mycobacteria were found in any sample from the five water taps suggesting another source of colonization. It is probable that residual water and biofilm are of importance. Our results emphasize the need for improved disinfection procedures and improved construction of the HCUs.


Assuntos
Desinfetantes/farmacologia , Contaminação de Equipamentos , Equipamentos e Provisões/microbiologia , Mycobacterium/isolamento & purificação , Microbiologia da Água , Biofilmes/efeitos dos fármacos , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Descontaminação/métodos , Fungos/efeitos dos fármacos , Fungos/isolamento & purificação , Humanos , Mycobacterium/efeitos dos fármacos , Infecções por Mycobacterium/prevenção & controle , Complexo Mycobacterium avium/efeitos dos fármacos , Complexo Mycobacterium avium/isolamento & purificação , Micobactérias não Tuberculosas/efeitos dos fármacos , Micobactérias não Tuberculosas/isolamento & purificação , Prata/farmacologia , Suécia
7.
J Clin Endocrinol Metab ; 102(11): 3928-3932, 2017 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-28938458

RESUMO

Context: Lynch syndrome (LS) is a cancer-predisposing syndrome caused by germline mutations in genes involved in DNA mismatch repair (MMR). Patients are at high risk for several types of cancer, but pituitary tumors have not previously been reported. Case: A 51-year-old man with LS (MSH2 mutation) and a history of colon carcinoma presented with severe Cushing disease and a locally aggressive pituitary tumor. The tumor harbored a mutation consistent with the patient's germline mutation and displayed defect MMR function. Sixteen months later, the tumor had developed into a carcinoma with widespread liver metastases. The patient prompted us to perform a nationwide study in LS. Nationwide Study: A diagnosis consistent with a pituitary tumor was sought for in the Swedish National Patient Registry. In 910 patients with LS, representing all known cases in Sweden, another two clinically relevant pituitary tumors were found: an invasive nonsecreting macroadenoma and a microprolactinoma (i.e., in total three tumors vs. one expected). Conclusion: Germline mutations in MMR genes may contribute to the development and/or the clinical course of pituitary tumors. Because tumors with MMR mutations are susceptible to treatment with immune checkpoint inhibitors, we suggest to actively ask for a family history of LS in the workup of patients with aggressive pituitary tumors.


Assuntos
Carcinoma/patologia , Neoplasias Colorretais Hereditárias sem Polipose/patologia , Neoplasias Hipofisárias/patologia , Carcinoma/genética , Estudos de Coortes , Neoplasias Colorretais Hereditárias sem Polipose/genética , Corticotrofos/patologia , Reparo de Erro de Pareamento de DNA/genética , Mutação em Linhagem Germinativa , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/secundário , Masculino , Pessoa de Meia-Idade , Neoplasias Hipofisárias/genética , Sistema de Registros , Suécia
8.
R Soc Open Sci ; 3(2): 150633, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26998334

RESUMO

The last decade has seen a surge in research on avian influenza A viruses (IAVs), in part fuelled by the emergence, spread and potential zoonotic importance of highly pathogenic virus subtypes. The mallard (Anas platyrhynchos) is the most numerous and widespread dabbling duck in the world, and one of the most important natural hosts for studying IAV transmission dynamics. In order to predict the likelihood of IAV transmission between individual ducks and to other hosts, as well as between geographical regions, it is important to understand how IAV infection affects the host. In this study, we analysed the movements of 40 mallards equipped with GPS transmitters and three-dimensional accelerometers, of which 20 were naturally infected with low pathogenic avian influenza virus (LPAIV), at a major stopover site in the Northwest European flyway. Movements differed substantially between day and night, as well as between mallards returning to the capture site and those feeding in natural habitats. However, movement patterns did not differ between LPAIV infected and uninfected birds. Hence, LPAIV infection probably does not affect mallard movements during stopover, with high possibility of virus spread along the migration route as a consequence.

9.
J Clin Endocrinol Metab ; 100(4): 1689-98, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25646794

RESUMO

CONTEXT/OBJECTIVE: Locally aggressive pituitary tumors (LAPT) and pituitary carcinomas respond poorly to conventional therapy and cytotoxic drugs. Temozolomide (TMZ) is an oral alkylating drug with good tolerability, approved for treatment of malignant gliomas. The experience of its use in pituitary tumors is limited. DESIGN AND SETTING: We report on 24 patients with aggressive pituitary tumors (16 LAPTs, 8 carcinomas) treated with TMZ for a median of 6 months (range 1-23). Follow-up ranged from 4 to 91 months with a median of 32.5 months. 19/24 tumors were hormone secreting (PRL 9, ACTH 4, GH 4, GH/PRL 2). Ki-67 was 2-50% in LAPTs, and 5-80% in carcinomas. MAIN OUTCOME: Response to TMZ and the association with tumor expression of O6-methylguanine DNA methyltransferase (MGMT), MLH1, MSH2, and MSH6, examined by immunohistochemistry. RESULTS: Complete tumor regression occurred in two carcinomas and persisted at follow-up after 48 and 91 months, respectively. Partial regress of tumor mass ranging from 35% to 80% occurred in 5 LAPTs and 2 carcinomas. Another patient with LAPT had a 71% decrease in prolactin levels without change in tumor volume. Three LAPTs could not be evaluated. Median MGMT staining was 9% (5-20%) in responders vs 93% (50-100%) in nonresponders. Loss of MSH2 and MSH 6 was observed in a single patient who had a rapid development of resistance to TMZ. CONCLUSIONS: This study shows that TMZ is a valuable treatment option for patients with uncontrolled pituitary tumors. The data suggest that tumoral MGMT staining below 50% is associated with a high likelihood of treatment response.


Assuntos
Adenoma/tratamento farmacológico , Antineoplásicos Alquilantes/uso terapêutico , Carcinoma/tratamento farmacológico , Metilases de Modificação do DNA/metabolismo , Enzimas Reparadoras do DNA/metabolismo , Dacarbazina/análogos & derivados , Neoplasias Hipofisárias/tratamento farmacológico , Proteínas Supressoras de Tumor/metabolismo , Adenoma/diagnóstico , Adenoma/metabolismo , Adenoma/patologia , Adolescente , Adulto , Idoso , Biomarcadores Farmacológicos/metabolismo , Biomarcadores Tumorais/metabolismo , Carcinoma/diagnóstico , Carcinoma/metabolismo , Carcinoma/patologia , Dacarbazina/uso terapêutico , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Hipofisárias/diagnóstico , Neoplasias Hipofisárias/metabolismo , Neoplasias Hipofisárias/patologia , Prognóstico , Temozolomida , Resultado do Tratamento , Adulto Jovem
10.
PLoS One ; 9(6): e100764, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24971887

RESUMO

The mallard (Anas platyrhynchos) is a focal species in game management, epidemiology and ornithology, but comparably little research has focused on the ecology of the migration seasons. We studied habitat use, time-budgets, home-range sizes, habitat selection, and movements based on spatial data collected with GPS devices attached to wild mallards trapped at an autumn stopover site in the Northwest European flyway. Sixteen individuals (13 males, 3 females) were followed for 15-38 days in October to December 2010. Forty-nine percent (SD = 8.4%) of the ducks' total time, and 85% of the day-time (SD = 28.3%), was spent at sheltered reefs and bays on the coast. Two ducks used ponds, rather than coast, as day-roosts instead. Mallards spent most of the night (76% of total time, SD = 15.8%) on wetlands, mainly on alvar steppe, or in various flooded areas (e.g. coastal meadows). Crop fields with maize were also selectively utilized. Movements between roosting and foraging areas mainly took place at dawn and dusk, and the home-ranges observed in our study are among the largest ever documented for mallards (mean  = 6,859 ha; SD = 5,872 ha). This study provides insights into relatively unknown aspects of mallard ecology. The fact that autumn-staging migratory mallards have a well-developed diel activity pattern tightly linked to the use of specific habitats has implications for wetland management, hunting and conservation, as well as for the epidemiology of diseases shared between wildlife and domestic animals.


Assuntos
Migração Animal/fisiologia , Patos/fisiologia , Comportamento de Retorno ao Território Vital/fisiologia , Estações do Ano , Animais , Animais Selvagens , Ecossistema , Feminino , Sistemas de Informação Geográfica , Masculino
11.
Proc Biol Sci ; 281(1781): 20140098, 2014 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-24573857

RESUMO

Data on long-term circulation of pathogens in wildlife populations are seldom collected, and hence understanding of spatial-temporal variation in prevalence and genotypes is limited. Here, we analysed a long-term surveillance series on influenza A virus (IAV) in mallards collected at an important migratory stopover site from 2002 to 2010, and characterized seasonal dynamics in virus prevalence and subtype diversity. Prevalence dynamics were influenced by year, but retained a common pattern for all years whereby prevalence was low in spring and summer, but increased in early autumn with a first peak in August, and a second more pronounced peak during October-November. A total of 74 haemagglutinin (HA)/neuraminidase (NA) combinations were isolated, including all NA and most HA (H1-H12) subtypes. The most common subtype combinations were H4N6, H1N1, H2N3, H5N2, H6N2 and H11N9, and showed a clear linkage between specific HA and NA subtypes. Furthermore, there was a temporal structuring of subtypes within seasons based on HA phylogenetic relatedness. Dissimilar HA subtypes tended to have different temporal occurrence within seasons, where the subtypes that dominated in early autumn were rare in late autumn, and vice versa. This suggests that build-up of herd immunity affected IAV dynamics in this system.


Assuntos
Doenças das Aves/epidemiologia , Doenças das Aves/virologia , Patos , Monitoramento Ambiental/estatística & dados numéricos , Vírus da Influenza A/genética , Influenza Aviária/epidemiologia , Migração Animal/fisiologia , Animais , Europa (Continente)/epidemiologia , Variação Genética , Imunidade Coletiva/imunologia , Prevalência , Estações do Ano
12.
PLoS One ; 8(4): e61201, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23637797

RESUMO

Wild dabbling ducks (genus Anas) are the main reservoir for influenza A virus (IAV) in the Northern Hemisphere. Current understanding of disease dynamics and epidemiology in this virus-host system has primarily been based on population-level surveillance studies and infection experiments conducted in laboratory settings. Using a combined experimental-natural approach with wild-strain captive mallards (Anas platyrhynchos), we monitored individual IAV infection histories and immunological responses of 10 birds over the course of 15 months. This is the first detailed study to track natural IAV infection histories over several seasons amongst the same individuals growing from juvenile to adults. The general trends in the infection histories of the monitored birds reflected seasonal variation in prevalence at the population level. However, within the study group there were significant differences between individuals in infection frequency as well as in short and long term anti-IAV antibody response. Further observations included individual variation in the number of infecting virus subtypes, and a strong tendency for long-lasting hemagglutinin-related homosubtypic immunity. Specifically, all infections in the second autumn, except one, were of different subtypes compared to the first autumn. The variation among birds concerning these epidemiologically important traits illustrates the necessity for IAV studies to move from the level of populations to examine individuals in order to further our understanding of IAV disease and epidemiology.


Assuntos
Anseriformes/virologia , Vírus da Influenza A/fisiologia , Influenza Aviária/imunologia , Animais , Feminino , Imunidade Humoral , Dados de Sequência Molecular , Fatores de Tempo , Eliminação de Partículas Virais
13.
Mov Ecol ; 1(1): 4, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-25709818

RESUMO

BACKGROUND: Understanding how environmental conditions, especially wind, influence birds' flight speeds is a prerequisite for understanding many important aspects of bird flight, including optimal migration strategies, navigation, and compensation for wind drift. Recent developments in tracking technology and the increased availability of data on large-scale weather patterns have made it possible to use path annotation to link the location of animals to environmental conditions such as wind speed and direction. However, there are various measures available for describing not only wind conditions but also the bird's flight direction and ground speed, and it is unclear which is best for determining the amount of wind support (the length of the wind vector in a bird's flight direction) and the influence of cross-winds (the length of the wind vector perpendicular to a bird's direction) throughout a bird's journey. RESULTS: We compared relationships between cross-wind, wind support and bird movements, using path annotation derived from two different global weather reanalysis datasets and three different measures of direction and speed calculation for 288 individuals of nine bird species. Wind was a strong predictor of bird ground speed, explaining 10-66% of the variance, depending on species. Models using data from different weather sources gave qualitatively similar results; however, determining flight direction and speed from successive locations, even at short (15 min intervals), was inferior to using instantaneous GPS-based measures of speed and direction. Use of successive location data significantly underestimated the birds' ground and airspeed, and also resulted in mistaken associations between cross-winds, wind support, and their interactive effects, in relation to the birds' onward flight. CONCLUSIONS: Wind has strong effects on bird flight, and combining GPS technology with path annotation of weather variables allows us to quantify these effects for understanding flight behaviour. The potentially strong influence of scaling effects must be considered and implemented in developing sampling regimes and data analysis.

14.
PLoS One ; 7(11): e49002, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23145046

RESUMO

During recent years, extensive amounts of data have become available regarding influenza A virus (IAV) in wild birds in northern Europe, while information from southern Europe is more limited. Here, we present an IAV surveillance study conducted in western Portugal 2008-2009, analyzing 1653 samples from six different species of waterfowl, with the majority of samples taken from Mallards (Anas platyrhynchos). Overall 4.4% of sampled birds were infected. The sampling results revealed a significant temporal variation in the IAV prevalence, including a pronounced peak among predominantly young birds in June, indicating that IAV circulate within breeding populations in the wetlands of western Portugal. The H10N7 and H9N2 subtypes were predominant among isolated viruses. Phylogenetic analyses of the hemagglutinin and neuraminidase sequences of H10N7, H9N2 and H11N3 virus showed that sequences from Portugal were closely related to viral sequences from Central Europe as well as to IAVs isolated in the southern parts of Africa, reflecting Portugal's position on the European-African bird migratory flyway. This study highlights the importance of Portugal as a migratory crossroad for IAV, connecting breeding stationary waterfowl with birds migrating between continents which enable transmission and spread of IAV.


Assuntos
Aves/virologia , Vírus da Influenza A Subtipo H10N7/isolamento & purificação , Vírus da Influenza A Subtipo H9N2/isolamento & purificação , Influenza Aviária/virologia , Migração Animal , Animais , Animais Selvagens/genética , Animais Selvagens/virologia , Feminino , Vírus da Influenza A Subtipo H10N7/genética , Vírus da Influenza A Subtipo H9N2/genética , Influenza Aviária/epidemiologia , Filogenia , Portugal/epidemiologia
16.
Circ Res ; 104(12): e62-70, 2009 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-19478203

RESUMO

The immune system represents a promising novel target for prevention of atherosclerosis. Several pilot vaccines that reduce atherosclerosis in experimental animals have been developed. The aluminum hydroxide adjuvant Alum has been shown to have antiatherogenic properties in itself, suggesting that it may be a suitable adjuvant in possible future atherosclerosis vaccines. To characterize the immune pathways mediating this protection, we treated wild-type C57BL/6 and Apoe(-)(/)(-) mice with Alum or PBS. Analyses of splenocytes isolated from 12-week-old mice demonstrated that Alum increased the presence of CD4(+)CD25(+)FoxP3(+) regulatory T cells and downregulated the expression of T cell activation markers CD28 and ICOS in Apoe(-)(/)(-) mice but not in C57BL/6 wild-type mice. A similar immunosuppressive phenotype was found also in 25-week-old Apoe(-)(/)(-) mice and was associated with reduced atherosclerosis. Alum precipitates recovered from the injection site of Apoe(-)(/)(-) mice contained antigens derived from oxidized LDL. These findings demonstrate that treatment of Apoe(-)(/)(-) mice with Alum results in an increase of regulatory T cells and suggest that these are activated by tolerogenic antigen-presenting cells presenting oxidized LDL antigens. Our findings provide improved mechanistic understanding of the atheroprotective properties of aluminum hydroxide adjuvants but also point to the importance of determining if hypercholesterolemia may compromise the efficacy of Alum-containing vaccines used clinically today.


Assuntos
Adjuvantes Imunológicos/farmacologia , Compostos de Alúmen/farmacologia , Aterosclerose/prevenção & controle , Tolerância Imunológica/efeitos dos fármacos , Lipoproteínas LDL/imunologia , Linfócitos T Reguladores/imunologia , Hidróxido de Alumínio/farmacologia , Animais , Células Apresentadoras de Antígenos/imunologia , Antígenos de Diferenciação de Linfócitos T/genética , Antígenos de Diferenciação de Linfócitos T/imunologia , Apolipoproteínas E/genética , Apolipoproteínas E/imunologia , Aterosclerose/genética , Aterosclerose/imunologia , Antígenos CD28/genética , Antígenos CD28/imunologia , Hipercolesterolemia/genética , Hipercolesterolemia/imunologia , Proteína Coestimuladora de Linfócitos T Induzíveis , Camundongos , Camundongos Knockout , Vacinas/imunologia , Vacinas/farmacologia
17.
Diabetes ; 55(5): 1407-12, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16644698

RESUMO

Cytokines, particularly interleukin (IL)-1beta, have been postulated to cause beta-cell destruction in type 1 diabetes. We tested the efficacy of an IL-1 cytokine trap in counteraction of suppressive and toxic effects after exposure of rat pancreatic islets in vitro to IL-1beta. The IL-1 cytokine trap used herein comprised extracellular domains of the IL-1 receptor accessory protein and the human IL-1 receptor 1 arranged inline and fused to the Fc portion of human IgG1. Groups of isolated rat pancreatic islets were maintained in medium culture with or without IL-1beta (150 pmol/l) for 48 hours in the absence or presence of the IL-1 trap at 1-, 10-, or 100-fold excess the molar concentration of the cytokine. IL-1beta alone induced a strong inhibition of insulin secretion and glucose oxidation rate and a marked increase in medium nitrite accumulation as an indicator of nitric oxide generation. When the IL-1 trap was used at a ratio 10:1 or 100:1, a complete protection against these effects were observed. Moreover, the IL-1 trap (100:1) blocked the increased islet cell death seen in islets treated with a combination of IL-1beta + tumor necrosis factor-alpha + interferon-gamma as well as functional suppression induced by the cytokine combination. In conclusion, we show that addition of an IL-1 trap can protect rat pancreatic islets in vitro against noxious effects induced by IL-1beta. Exploring the IL-1 trap in relevant animal models of type 1 diabetes represents an interesting future intervention strategy.


Assuntos
Citocinas/antagonistas & inibidores , Citocinas/fisiologia , Interleucina-1/farmacologia , Ilhotas Pancreáticas/citologia , Animais , Citometria de Fluxo , Glucose/metabolismo , Insulina/metabolismo , Secreção de Insulina , Ilhotas Pancreáticas/efeitos dos fármacos , Ilhotas Pancreáticas/fisiologia , Masculino , Nitritos/metabolismo , Ratos , Ratos Sprague-Dawley
18.
Appl Opt ; 44(10): 1934-41, 2005 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-15813529

RESUMO

The fluorescence spectrum measured from a fluorophore in tissue is affected by the absorption and scattering properties of the tissue, as well as by the measurement geometry. We analyze this effect with Monte Carlo simulations and by measurements on phantoms. The spectral changes can be used to estimate the depth of a fluorescent lesion embedded in the tissue by measurement of the fluorescence signal in different wavelength bands. By taking the ratio between the signals at two wavelengths, we show that it is possible to determine the depth of the lesion. Simulations were performed and validated by measurements on a phantom in the wavelength range 815-930 nm. The depth of a fluorescing layer could be determined with 0.6-mm accuracy down to at least a depth of 10 mm. Monte Carlo simulations were also performed for different tissue types of various composition. The results indicate that depth estimation of a lesion should be possible with 2-3-mm accuracy, with no assumptions made about the optical properties, for a wide range of tissues.


Assuntos
Algoritmos , Interpretação de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Nefelometria e Turbidimetria/métodos , Espectrometria de Fluorescência/métodos , Método de Monte Carlo , Nefelometria e Turbidimetria/instrumentação , Imagens de Fantasmas , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Espectrometria de Fluorescência/instrumentação
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