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1.
Vaccines (Basel) ; 12(4)2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38675825

RESUMO

Candidate vaccines against African swine fever virus (ASFV) based on naturally attenuated or genetically modified viruses have the potential to generate protective immune responses, although there is no consensus on what defines a protective immune response against ASFV. Studies, especially in sensitive host species and focused on unravelling protective mechanisms, will contribute to the development of safer and more effective vaccines. The present study provides a detailed analysis of phenotypic and functional data on cellular responses induced by intradermal immunization and subsequent boosting of domestic pigs with the naturally attenuated field strain Lv17/WB/Rie1, as well as the mechanisms underlying protection against intramuscular challenge with the virulent genotype II Armenia/07 strain. The transient increase in IL-8 and IL-10 in serum observed after immunization might be correlated with survival. Protection was also associated with a robust ASFV-specific polyfunctional memory T-cell response, where CD4CD8 and CD8 T cells were identified as the main cellular sources of virus-specific IFNγ and TNFα. In parallel with the cytokine response, these T-cell subsets also showed specific cytotoxic activity as evidenced by the increased expression of the CD107a degranulation marker. Along with virus-specific multifunctional CD4CD8 and CD8 T-cell responses, the increased levels of antigen experienced in cytotoxic CD4 T cells observed after the challenge in immunized pigs might also contribute to controlling virulent infection by killing mechanisms targeting infected antigen-presenting cells. Future studies should elucidate whether the memory T-cell responses evidenced in the present study persist and provide long-term protection against further ASFV infections.

2.
Ann Geriatr Med Res ; 28(1): 9-19, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37963716

RESUMO

BACKGROUND: While multidimensional and interdisciplinary assessment of older adult patients improves their short-term outcomes after evaluation in the emergency department (ED), this assessment is time-consuming and ill-suited for the busy environment. Thus, identifying patients who will benefit from this strategy is challenging. Therefore, this study aimed to identify older adult patients suitable for a different ED approach as well as independent variables associated with poor short-term clinical outcomes. METHODS: We included all patients ≥65 years attending 52 EDs in Spain over 7 days. Sociodemographic, comorbidity, and baseline functional status data were collected. The outcomes were 30-day mortality, re-presentation, hospital readmission, and the composite of all outcomes. RESULTS: During the study among 96,014 patients evaluated in the ED, we included 23,338 patients ≥65 years-mean age, 78.4±8.1 years; 12,626 (54.1%) women. During follow-up, 5,776 patients (24.75%) had poor outcomes after evaluation in the ED: 1,140 (4.88%) died, 4,640 (20.51) returned to the ED, and 1,739 (7.69%) were readmitted 30 days after discharge following the index visit. A model including male sex, age ≥75 years, arrival by ambulance, Charlson Comorbidity Index ≥3, and functional impairment had a C-index of 0.81 (95% confidence interval, 0.80-0.82) for 30-day mortality. CONCLUSION: Male sex, age ≥75 years, arrival by ambulance, functional impairment, or severe comorbidity are features of patients who could benefit from approaches in the ED different from the common triage to improve the poor short-term outcomes of this population.

3.
Rev Esp Salud Publica ; 972023 Oct 17.
Artigo em Espanhol | MEDLINE | ID: mdl-37921381

RESUMO

OBJECTIVE: Functional assessment is part of geriatric assessment. How it is performed in hospital Emergency Departments (ED) is poorly understood, let alone its prognostic value. The aim of this paper was to investigate whether baseline disability to perform basic activities of daily living (BADL) was an independent prognostic factor for death after the index visit to the ED during the first wave of the COVID-19 pandemic and whether it had a different impact on patients with and without diagnosis of COVID-19. METHODS: A retrospective observational study of the EDEN-Covid (Emergency Department and Elder Needs during COVID) cohort was carried out, consisting of all patients aged ≥65 years seen in 52 Spanish EDs selected by chance during 7 consecutive days (30/3/2020 to 5/4/2020). Demographic, clinical, functional, mental and social variables were analyzed. Dependence was categorized with the Barthel index (BI) as independent (BI=100), mild-moderate dependence (100>BI>60) and severe-total dependence (BI<60), and their crude and adjusted association was evaluated with mortality at 30, 180 and 365 days using COX proportional hazards models. RESULTS: Of 9,770 enrolled patients with a mean age of 79 years, 51% were men, 6,305 (64.53%) were independent, 2,340 (24%) had mild-moderate dependence, and 1,125 (11.5%) severe-total dependence. The number of deaths at 30 days in these three groups was 500 (7.9%), 521 (22.3%) and 378 (33.6%), respectively; at 180 days it was 757 (12%), 725 (30.9%) and 526 (46.8%); and at 365 days 954 (15.1%), 891 (38.1%) and 611 (54.3%). In relation to independent patients, the adjusted risks (hazard ratio) of dying within 30 days associated with mild-moderate and severe-total dependency were 1.91 (95% CI: 1.66-2.19) and 2.51. (2.11-2.98); at 180 days they were 1.88 (1.68-2.11) and 2.64 (2.28-3.05); and at 365 days they were 1.82 (1.64-2.02) and 2.47 (2.17-2.82). This negative impact of dependency on mortality was greater in patients diagnosed with COVID-19 than in non-COVID-19 (p interaction at 30, 180 and 365 days of 0.36, 0.05 and 0.04). CONCLUSIONS: The functional dependence of older patients who attend Spanish EDs during the first wave of the pandemic is associated with mortality at 30, 180 and 365 days, and this risk is significantly higher in patients treated for COVID-19.


OBJETIVO: La valoración funcional forma parte de la valoración geriátrica. No se conoce bien cómo se realiza en los servicios de Urgencias hospitalarios (SUH) y menos aún su valor pronóstico. El objetivo de este trabajo fue investigar si la dependencia funcional basal para realizar las actividades básicas de la vida diaria (ABVD) era un factor pronóstico independiente de muerte tras la visita índice al SUH durante la primera ola pandémica de la COVID-19 y si tuvo un impacto diferente en pacientes con y sin diagnóstico de COVID-19. METODOS: Se realizó un estudio observacional retrospectivo de la cohorte EDEN-Covid (Emergency Department and Elder Needs during COVID) formada por todos los pacientes de edad mayor o igual a 65 años atendidos en 52 SUH españoles, seleccionados por oportunidad durante siete días consecutivos (del 30 de marzo al 5 de abril de 2020). Se analizaron variables demográficas, clínicas, funcionales, mentales y sociales. La dependencia se categorizó con el índice de Barthel (IB) en independiente (IB=100), dependencia leve-moderada (100>IB>60) y dependencia grave-total (IB<60), y se evaluó su asociación cruda y ajustada con la mortalidad a 30, 180 y 365 días mediante modelos de riesgos proporcionales de COX. RESULTADOS: De 9.770 pacientes incluidos con una media de edad de 79 años, un 51% eran hombres, 6.305 (64,53%) eran independientes, 2.340 (24%) tenían dependencia leve-moderada y 1.125 (11,5%) dependencia grave-total. El número de fallecidos a 30 días en estos tres grupos fue 500 (7,9%), 521 (22,3%) y 378 (33,6%), respectivamente; a 180 días fue 757 (12%), 725 (30,9%) y 526 (46,8%); y a 365 días 954 (15,1%), 891 (38,1%) y 611 (54,3%). En relación a los pacientes independientes, los riesgos (hazard ratio) ajustados de fallecer a 30 días, asociados a dependencia leve-moderada y grave-total, fueron 1,91 (IC 95%: 1,66-2,19) y 2,51 (2,11-2,98); a 180 días fueron de 1,88 (1,68-2,11) y 2,64 (2,28-3,05); y a 365 días fueron 1,82 (1,64-2,02) y 2,47 (2,17-2,82). Este impacto negativo de la dependencia sobre la mortalidad fue mayor en pacientes diagnosticados de COVID-19 que en los no COVID-19 (p interacción a 30, 180 y 365 días de 0,36, 0,05 y 0,04). CONCLUSIONES: La dependencia funcional de los pacientes mayores que acuden a SUH españoles durante la primera ola pandémica se asocia a mortalidad a 30, 180 y 365 días, y este riesgo es significativamente mayor en los pacientes atendidos por COVID-19.


Assuntos
Atividades Cotidianas , COVID-19 , Masculino , Humanos , Idoso , Feminino , Pandemias , Espanha/epidemiologia , Estudos Retrospectivos , Complicações Pós-Operatórias/epidemiologia
4.
Front Vet Sci ; 10: 1112850, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36761884

RESUMO

Introduction: African swine fever (ASF) is a contagious viral disease of pigs and wild boar that poses a major threat to the global swine industry. The genotype II African swine fever virus (ASFV) entered the European Union (EU) in 2014 and since then fourteen countries have been affected, Italy and North Macedonia being the last in 2022. While whole genome sequencing remains the gold standard for the identification of new genetic markers, sequencing of multiple loci with significant variations could be used as a rapid and cost-effective alternative to track outbreaks and study disease evolution in endemic areas. Materials and methods: To further our understanding of the epidemiology and spread of ASFV in Europe, 382 isolates collected during 2007 to 2022 were sequenced. The study was initially performed by sequencing the central variable region (CVR), the intergenic region (IGR) between the I73R and I329L genes and the O174L and K145R genes. For further discrimination, two new PCRs were designed to amplify the IGR between the 9R and 10R genes of the multigene family 505 (MGF505) and the IGR between the I329L and I215L genes. The sequences obtained were compared with genotype II isolates from Europe and Asia. Results: The combination of the results obtained by sequencing these variable regions allowed to differentiate the European II-ASFV genotypes into 24 different groups. In addition, the SNP identified in the IGR I329L-I215L region, not previously described, grouped the viruses from North Macedonia that caused the 2022 outbreaks with viruses from Romania, Bulgaria, Serbia and Greece, differentiating from other genotype II isolates present in Europe and Asia. Furthermore, tandem repeat sequence (TRS) within the 9R-10R genes of the multigene family 505 (MGF505) revealed eight different variants circulating. Discussion: These findings describe a new multi-gene approach sequencing method that can be used in routine genotyping to determine the origin of new introductions in ASF-free areas and track infection dynamics in endemic areas.

5.
Sensors (Basel) ; 22(15)2022 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-35898078

RESUMO

This paper shows wind speed measurements from the TASEC-Lab experiment in a stratospheric balloon mission. The mission was launched in July 2021 from León (Spain) aerodrome. Measurements of horizontal wind speed in relation to the balloon gondola were successfully carried out with a cup anemometer. According to the available literature, this is the first time a cup anemometer has been used in a stratospheric balloon mission. The results indicate the need to consider the horizontal wind speed from the balloon ascent phase for thermal calculations of the mission.

6.
Transbound Emerg Dis ; 68(5): 2826-2841, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34273247

RESUMO

This study aimed to compare the infection dynamics of three genotype II African swine fever viruses (ASFV) circulating in Europe. Eighteen domestic pigs divided into three groups were infected intramuscularly or by direct contact with two haemadsorbent ASFVs (HAD) from Poland (Pol16/DP/ OUT21) and Estonia (Est16/WB/Viru8), and with the Latvian non-HAD ASFV (Lv17/WB/Rie1). Parameters, such as symptoms, pathogenicity, and distribution of the virus in tissues, humoral immune response, and dissemination of the virus by blood, oropharyngeal and rectal routes, were investigated. The Polish ASFV caused a case of rapidly developing fatal acute disease, while the Estonian ASFV caused acute to sub-acute infections and two animals survived. In contrast, animals infected with the ASFV from Latvia developed a more subtle, mild, or even subclinical disease. Oral excretion was sporadic or even absent in the attenuated group, whereas in animals that developed an acute or sub-acute form of ASF, oral excretion began at the same time the ASFV was detected in the blood, or even 3 days earlier, and persisted up to 22 days. Regardless of virulence, blood was the main route of transmission of ASFV and infectious virus was isolated from persistently infected animals for at least 19 days in the attenuated group and up to 44 days in the group of moderate virulence. Rectal excretion was limited to the acute phase of infection. In terms of diagnostics, the ASFV genome was detected in contact pigs from oropharyngeal samples earlier than in blood, independently of virulence. Together with blood, both samples could allow to detect ASFV infection for a longer period. The results presented here provide quantitative data on the spread and excretion of ASFV strains of different virulence among domestic pigs that can help to better focus surveillance activities and, thus, increase the ability to detect ASF introductions earlier.


Assuntos
Vírus da Febre Suína Africana , Febre Suína Africana , Doenças dos Suínos , Febre Suína Africana/epidemiologia , Vírus da Febre Suína Africana/genética , Animais , Genótipo , Sus scrofa , Suínos , Virulência
7.
Anim Reprod Sci ; 211: 106227, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31785635

RESUMO

Artificial insemination (AI) in pigs is mainly performed with refrigerated boar semen. There is a marked negative seasonal effect on the quality of boar sperm, mainly due to relatively greater ambient temperatures; to counteract this thermal stress, sperm cells possess natural defensive mechanisms such as Heat Shock Proteins (HSPs) that prevent protein denaturation. Thus, the objective of this research was to improve the quality of commercial boar semen collected during the summer when ambient temperatures are greater using recombinant HSPs. For this purpose, different concentrations (0.1, 0.5 and 1 µg/ml) of recombinant heat shock proteins (HSPD1, HSPA8 or HSP86) were added to commercial boar semen and there was cooling for 48 h at 17 °C. After this storage period, sperm quality was assessed by analyzing sperm viability, mitochondrial membrane potential and plasma membrane lipid organization using flow cytometry; additionally, sperm motility was examined using a CASA system. Also, in vitro fertilization (IVF) using HSP-supplemented boar semen was performed and the quality of the embryos produced was evaluated using quantitative real-time polymerase chain reaction (qPCR) analyzing the relative abundance of mRNA transcripts for genes encoding for embryo quality-related proteins (BAX, TFAM, POLG and POG2). Sperm quality variables, blastocyst rates and the abundance of mRNA transcripts for the selected genes were not affected by the presence of recombinant HSPs at any concentration. These results indicate that the supplementation of commercial seminal doses with recombinant HSPs does not improve boar sperm quality or fertility during the summer months when ambient temperatures are greater.


Assuntos
Proteínas de Choque Térmico/farmacologia , Inseminação Artificial/veterinária , Análise do Sêmen/veterinária , Sêmen , Suínos/fisiologia , Animais , Sobrevivência Celular , Relação Dose-Resposta a Droga , Proteínas de Choque Térmico/administração & dosagem , Masculino , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Proteínas Recombinantes , Estações do Ano , Motilidade dos Espermatozoides
8.
J Reconstr Microsurg ; 35(7): 541-548, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31067581

RESUMO

BACKGROUND: In microsurgical reconstruction, vascular obstruction occurs in approximately 20% of patients. Close monitoring is central to their care. Clinical/Doppler detection of vascular obstruction could be enhanced by thermography. METHODS: A diagnostic test design included consecutive cases of hospitalized patients, ≥18 years old, who underwent surgery with free flaps. Two researchers separately evaluated patients with clinical/Doppler methods and thermographic camera hourly for 24 hours, every 2 hours for the next 24 hours, and then every 3 hours until discharge. The gold standard was visualization of thrombus or vascular obstruction during surgical reintervention. Sensitivity, specificity, positive/negative predictive value (PPV/NPV), and a delta temperature receiver operating characteristic (ROC) curve were calculated. RESULTS: A total of 2,364 tests were performed with a thermographic camera in 40 patients (31 females, 9 males) aged 50.12 ± 9.7 years. There were 28 deep inferior epigastric perforator, 5 anterolateral thigh, 3 radial, 2 scapular, 1 fibular, and 1 anteromedial thigh flaps included. Six (15%) had postoperative vascular obstruction (5 venous and 1 arterial). One flap developed partial necrosis and one total necrosis (overall survival 97.5%). ROC curve (area 0.97) showed the best results at ≥ 1.8°C of difference to the surrounding skin. Considering two consecutive positive evaluations, the sensitivity was 93%, specificity 96%, PPV 57%, and NPV 99%. The thermal imaging camera allows to identify the obstruction between 2 and 12 hours before the clinical method. CONCLUSION: Utilizing a thermographic camera can reduce detection time of vascular obstruction by several hours in microvascular free flaps that include the cutaneous island. This method proves useful for early diagnosis of postoperative vascular obstruction.


Assuntos
Retalhos de Tecido Biológico/irrigação sanguínea , Oclusão de Enxerto Vascular/diagnóstico , Termografia/instrumentação , Diagnóstico Precoce , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade
9.
Transbound Emerg Dis ; 66(3): 1399-1404, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30667598

RESUMO

A non-haemadsorbing (non-HAD) ASF virus (ASFV) genotype II, namely Lv17/WB/Rie1, was isolated from a hunted wild boar in Latvia in 2017. Domestic pigs experimentally infected with the non-HAD ASFV developed a nonspecific or subclinical form of the disease. Two months later, these animals were fully protected when exposed to other domestic pigs infected with a related virulent HAD genotype II ASFV.


Assuntos
Vírus da Febre Suína Africana/imunologia , Febre Suína Africana/virologia , Febre Suína Africana/epidemiologia , Vírus da Febre Suína Africana/genética , Vírus da Febre Suína Africana/isolamento & purificação , Vírus da Febre Suína Africana/patogenicidade , Animais , Infecções Assintomáticas , Proteção Cruzada , Europa (Continente)/epidemiologia , Genótipo , Letônia/epidemiologia , Sus scrofa , Suínos
10.
Vaccine ; 36(19): 2694-2704, 2018 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-29609966

RESUMO

The risk of spread of African swine fever virus (ASFV) from Russia and Caucasian areas to several EU countries has recently emerged, making it imperative to improve our knowledge and defensive tools against this important pathogen. The ASFV genome encodes many genes which are not essential for virus replication but are known to control host immune evasion, such as NFκB and the NFAT regulator A238L, the apoptosis inhibitor A224L, the MHC-I antigen presenting modulator EP153R, and the A276R gene, involved in modulating type I IFN. These genes are hypothesized to be involved in virulence of the genotype I parental ASFV NH/P68. We here describe the generation of putative live attenuated vaccines (LAV) prototypes by constructing recombinant NH/P68 viruses lacking these specific genes and containing specific markers.


Assuntos
Vírus da Febre Suína Africana/genética , Febre Suína Africana/prevenção & controle , Vacinas Atenuadas/farmacologia , Vacinas Virais/farmacologia , Vírus da Febre Suína Africana/patogenicidade , Animais , Células COS , Chlorocebus aethiops , Interações Hospedeiro-Patógeno/genética , Mutação , Suínos , Vacinas Atenuadas/imunologia , Proteínas Virais/genética , Proteínas Virais/imunologia , Vacinas Virais/imunologia , Virulência/genética
11.
PLoS One ; 13(2): e0192565, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29489860

RESUMO

African swine fever (ASF) is a complex infectious disease of swine that constitutes devastating impacts on animal health and the world economy. Here, we investigated the evolutionary epidemiology of ASF virus (ASFV) in Eurasia and Africa using the concatenated gene sequences of the viral protein 72 and the central variable region of isolates collected between 1960 and 2015. We used Bayesian phylodynamic models to reconstruct the evolutionary history of the virus, to identify virus population demographics and to quantify dispersal patterns between host species. Results suggest that ASFV exhibited a significantly high evolutionary rate and population growth through time since its divergence in the 18th century from East Africa, with no signs of decline till recent years. This increase corresponds to the growing pig trade activities between continents during the 19th century, and may be attributed to an evolutionary drift that resulted from either continuous circulation or maintenance of the virus within Africa and Eurasia. Furthermore, results implicate wild suids as the ancestral host species (root state posterior probability = 0.87) for ASFV in the early 1700s in Africa. Moreover, results indicate the transmission cycle between wild suids and pigs is an important cycle for ASFV spread and maintenance in pig populations, while ticks are an important natural reservoir that can facilitate ASFV spread and maintenance in wild swine populations. We illustrated the prospects of phylodynamic methods in improving risk-based surveillance, support of effective animal health policies, and epidemic preparedness in countries at high risk of ASFV incursion.


Assuntos
Febre Suína Africana/epidemiologia , Asfarviridae/genética , Epidemiologia Molecular , Filogenia , África/epidemiologia , Febre Suína Africana/virologia , Animais , Asfarviridae/classificação , Ásia/epidemiologia , Europa (Continente)/epidemiologia , Genes Virais , Suínos
13.
J Child Health Care ; 21(2): 153-161, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29119810

RESUMO

Few studies have evaluated the changes in physical fitness (PF) of obese children and adolescents of a physical activity program for the treatment of obesity, and even fewer have explored the modality of home-based physical exercise. The objective of this study is to evaluate the changes in PF and body composition (BC) of a home-based physical exercise for treating childhood obesity. Thirty-three overweight/obese children and adolescents participated for six months in a home-based intervention that combined aerobics and muscular strength exercises. The results were compared, before and after the intervention, for the different PF components (VO2max, abdominal muscle resistance strength, and lower body explosive strength) and BC (body mass index Z-score (BMI-Z), percentage of body fat, and fat-free mass) variables. A significant reduction was observed in the percentage of body fat (4.7%) and the BMI- Z score (.23), and there was an increase in the fat-free mass of 2.9 kg ( p < .001). In addition, the VO2max showed a significant increase ( p < .05). The results of the different strength tests also showed significant improvements ( p < .05). Our findings support the effectiveness of this program improving not only BC but also PF. However, our results should be interpreted with caution due to lack of control group.


Assuntos
Índice de Massa Corporal , Serviços de Assistência Domiciliar , Obesidade Infantil/prevenção & controle , Aptidão Física/fisiologia , Adolescente , Criança , Feminino , Humanos , Masculino , Força Muscular , Estudos Prospectivos
14.
Sci Rep ; 6: 31265, 2016 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-27507613

RESUMO

Spider orb webs are multifunctional structures, the main function of which is to dissipate the kinetic energy of the impacting prey, while minimizing structural damage. There is no single explanation for their remarkable strength and ductility. However, it is clear that topology is decisive in the structural performance upon impact, and the arrangement of the different silk threads in the web must also exert an effect. The aim of this study is to show how a slight variation in the geometry markedly affects the prey-capture ability of spider orb webs. The study is focused on the secondary frame, a thread interposed between radial and primary frame strands, the importance of which has not been examined until now. The simulation of the impact performance of webs using different lengths of the secondary frame clarifies its structural role, which has proven to be decisive. Furthermore, the study explains why secondary frame threads of moderate length, as commonly encountered, enable the capture of prey with higher energy without a marked increase in the volume of silk used.


Assuntos
Seda/química , Aranhas/fisiologia , Resistência à Tração , Algoritmos , Animais , Fenômenos Biomecânicos , Simulação por Computador , Análise de Elementos Finitos , Comportamento Predatório , Estresse Mecânico
15.
Emerg Infect Dis ; 20(9): 1544-7, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25148518

RESUMO

African swine fever virus (ASFV) was first reported in eastern Europe/Eurasia in 2007. Continued spread of ASFV has placed central European countries at risk, and in 2014, ASFV was detected in Lithuania and Poland. Sequencing showed the isolates are identical to a 2013 ASFV from Belarus but differ from ASFV isolated in Georgia in 2007.


Assuntos
Vírus da Febre Suína Africana/genética , Febre Suína Africana/epidemiologia , Febre Suína Africana/virologia , Variação Genética , Genótipo , Animais , Sequência de Bases , Europa (Continente)/epidemiologia , Evolução Molecular , Genes Virais , Dados de Sequência Molecular , Filogenia , Alinhamento de Sequência , Suínos
16.
J R Soc Interface ; 11(98): 20140484, 2014 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-24966235

RESUMO

An orb-weaving spider's likelihood of survival is influenced by its ability to retain prey with minimum damage to its web and at the lowest manufacturing cost. This set of requirements has forced the spider silk to evolve towards extreme strength and ductility to a degree that is rare among materials. Previous studies reveal that the performance of the web upon impact may not be based on the mechanical properties of silk alone, aerodynamic drag could play a role in the dissipation of the prey's energy. Here, we present a thorough analysis of the effect of the aerodynamic drag on wind load and prey impact. The hypothesis considered by previous authors for the evaluation of the drag force per unit length of thread has been revisited according to well-established principles of fluid mechanics, highlighting the functional dependence on thread diameter that was formerly ignored. Theoretical analysis and finite-element simulations permitted us to identify air drag as a relevant factor in reducing deterioration of the orb web, and to reveal how the spider can take greater-and not negligible-advantage of drag dissipation. The study shows the beneficial air drag effects of building smaller and less dense webs under wind load, and larger and denser webs under prey impact loads. In essence, it points out why the aerodynamics need to be considered as an additional driving force in the evolution of silk threads and orb webs.


Assuntos
Seda/fisiologia , Aranhas/fisiologia , Ar , Animais , Evolução Biológica , Fenômenos Biomecânicos , Análise de Elementos Finitos , Comportamento Predatório , Resistência à Tração , Vento
17.
Vet Microbiol ; 165(1-2): 135-9, 2013 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-23374655

RESUMO

African swine fever (ASF) is a complex, highly lethal, notifiable disease of swine. ASF is wide-spread in sub-Saharan Africa and East European countries and there is presently a great risk of spread to neighboring countries. Since there is no vaccine for ASF virus (ASFV), control is based on rapid and early detection of the disease via surveillance. This approach requires collecting blood samples from large number of animals. Laborious and expensive of itself, this process also presents an additional risk because ASFV is present at high concentrations in the blood. The objective of this study was to initiate studies into the potential use of oral fluid as an alternative to serum for ASF diagnosis, for latter studying its possible use in surveillance and control programs. To this end, oral fluid samples collected at different times post infection from eight pigs experimentally inoculated with an attenuated ASFV were assayed using modified protocols of the two validated serological techniques, the enzyme-immune-liked assay (ELISA) and immunoperoxidase technique (IPT). Antibodies against ASFV were detected in oral fluid samples of all animals from early post infection through the end of the experiment by ELISA and IPT. These results confirmed the presence of ASFV antibodies in swine oral fluids samples, the possibility of an oral fluid-based approach in ASF diagnosis and, potentially in ASF surveillance.


Assuntos
Vírus da Febre Suína Africana/isolamento & purificação , Febre Suína Africana/diagnóstico , Ensaio de Imunoadsorção Enzimática/veterinária , Saliva/virologia , África Subsaariana/epidemiologia , Febre Suína Africana/epidemiologia , Febre Suína Africana/imunologia , Febre Suína Africana/virologia , Vírus da Febre Suína Africana/imunologia , Animais , Anticorpos Antivirais/análise , Ensaio de Imunoadsorção Enzimática/métodos , Suínos
18.
Cancer Discov ; 2(8): 722-35, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22822050

RESUMO

UNLABELLED: Indoleamine 2,3-dioxygenase (IDO) enzyme inhibitors have entered clinical trials for cancer treatment based on preclinical studies, indicating that they can defeat immune escape and broadly enhance other therapeutic modalities. However, clear genetic evidence of the impact of IDO on tumorigenesis in physiologic models of primary or metastatic disease is lacking. Investigating the impact of Ido1 gene disruption in mouse models of oncogenic KRAS-induced lung carcinoma and breast carcinoma-derived pulmonary metastasis, we have found that IDO deficiency resulted in reduced lung tumor burden and improved survival in both models. Micro-computed tomographic (CT) imaging further revealed that the density of the underlying pulmonary blood vessels was significantly reduced in Ido1-nullizygous mice. During lung tumor and metastasis outgrowth, interleukin (IL)-6 induction was greatly attenuated in conjunction with the loss of IDO. Biologically, this resulted in a consequential impairment of protumorigenic myeloid-derived suppressor cells (MDSC), as restoration of IL-6 recovered both MDSC suppressor function and metastasis susceptibility in Ido1-nullizygous mice. Together, our findings define IDO as a prototypical integrative modifier that bridges inflammation, vascularization, and immune escape to license primary and metastatic tumor outgrowth. SIGNIFICANCE: This study provides preclinical, genetic proof-of-concept that the immunoregulatory enzyme IDO contributes to autochthonous carcinoma progression and to the creation of a metastatic niche. IDO deficiency in vivo negatively impacted both vascularization and IL-6­dependent, MDSC-driven immune escape, establishing IDO as an overarching factor directing the establishment of a protumorigenic environment.


Assuntos
Indolamina-Pirrol 2,3,-Dioxigenase/antagonistas & inibidores , Neoplasias Pulmonares/enzimologia , Adenocarcinoma/irrigação sanguínea , Adenocarcinoma/enzimologia , Adenocarcinoma/genética , Adenocarcinoma/patologia , Adenocarcinoma de Pulmão , Animais , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/metabolismo , Transformação Celular Neoplásica/patologia , Progressão da Doença , Genes ras , Células HL-60 , Humanos , Indolamina-Pirrol 2,3,-Dioxigenase/deficiência , Indolamina-Pirrol 2,3,-Dioxigenase/genética , Indolamina-Pirrol 2,3,-Dioxigenase/metabolismo , Inflamação/tratamento farmacológico , Inflamação/enzimologia , Interleucina-6/biossíntese , Estimativa de Kaplan-Meier , Neoplasias Pulmonares/irrigação sanguínea , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/secundário , Neoplasias Mamárias Experimentais/enzimologia , Neoplasias Mamárias Experimentais/patologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Metástase Neoplásica , Neovascularização Patológica/enzimologia , Análise de Sobrevida , Células U937
19.
Dig Dis Sci ; 57(7): 1813-21, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22526583

RESUMO

BACKGROUND: Inflammatory bowel disease (IBD) is associated with defects in intestinal barriers that rely upon cellular tight junctions. Thus, identifying genes that could be targeted to enforce tight junctions and improve barrier function may lead to new treatment strategies for IBD. AIMS: This preclinical study aimed to evaluate an hypothesized role for the tumor suppressor gene Bin1 as a modifier of the severity of experimental colitis. METHODS: We ablated the Bin1 gene in a mosaic mouse model to evaluate its effects on experimental colitis and intestinal barrier function. Gross pathology, histology and inflammatory cytokine expression patterns were characterized and ex vivo physiology determinations were conducted to evaluate barrier function in intact colon tissue. RESULTS: Bin1 attenuation limited experimental colitis in a sexually dimorphic manner with stronger protection in female subjects. Colitis suppression was associated with an increase in basal transepithelial electrical resistance (TER) and a decrease in paracellular transepithelial flux, compared to control wild-type animals. In contrast, Bin1 attenuation did not affect short circuit current, nor did it alter the epithelial barrier response to non-inflammatory permeability enhancers in the absence of inflammatory stimuli. CONCLUSIONS: Bin1 is a genetic modifier of experimental colitis that controls the paracellular pathway of transcellular ion transport regulated by cellular tight junctions. Our findings offer a preclinical validation of Bin1 as a novel therapeutic target for IBD treatment.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/deficiência , Permeabilidade da Membrana Celular/fisiologia , Colite/prevenção & controle , Mucosa Intestinal/fisiologia , Proteínas do Tecido Nervoso/deficiência , Proteínas Supressoras de Tumor/deficiência , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/fisiologia , Animais , Colite/induzido quimicamente , Colite/patologia , Sulfato de Dextrana/efeitos adversos , Modelos Animais de Doenças , Feminino , Mucosa Intestinal/patologia , Masculino , Camundongos , Camundongos Knockout , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/fisiologia , Índice de Gravidade de Doença , Caracteres Sexuais , Junções Íntimas/fisiologia , Proteínas Supressoras de Tumor/genética , Proteínas Supressoras de Tumor/fisiologia
20.
Cancer Biol Ther ; 12(12): 1050-8, 2011 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-22157149

RESUMO

Indoleamine 2,3-dioxygenase (IDO) modifies adaptive immunity, in part by determining the character of inflammatory responses in the tissue microenvironment. Small molecule inhibitors of IDO are being developed to treat cancer, chronic infections and other diseases, so the systemic effects of IDO disruption on inflammatory phenomena may influence the design and conduct of early phase clinical investigations of this new class of therapeutic agents. Here, we report cardiac and gastrointestinal phenotypes observed in IDO deficient mice that warrant consideration in planned assessments of the safety risks involved in clinical development of IDO inhibitors. Calcification of the cardiac endometrium proximal to the right ventricle was a sexually dimorphic strain-specific phenotype with ~30% penetrance in BALB/c mice lacking IDO. Administration of complete Freund's adjuvant containing Toll-like receptor ligands known to induce IDO caused acute pancreatitis in IDO deficient mice, with implications for the design of planned combination studies of IDO inhibitors with cancer vaccines. In an established model of hyperlipidemia, IDO deficiency caused a dramatic elevation in levels of serum triglycerides. In the large intestine, IDO loss only slightly increased sensitivity to induction of acute colitis, but it markedly elevated tumor incidence, multiplicity and staging during inflammatory colon carcinogenesis. Together, our findings suggest potential cardiac and gastrointestinal risks of IDO inhibitors that should be monitored in patients as this new class of drugs enter early clinical development.


Assuntos
Gastroenteropatias/enzimologia , Cardiopatias/enzimologia , Indolamina-Pirrol 2,3,-Dioxigenase/deficiência , Animais , Cálcio/metabolismo , Transformação Celular Neoplásica/metabolismo , Colesterol/sangue , Neoplasias do Colo/enzimologia , Neoplasias do Colo/genética , Endométrio/metabolismo , Feminino , Adjuvante de Freund/efeitos adversos , Adjuvante de Freund/farmacologia , Gastroenteropatias/metabolismo , Gastroenteropatias/patologia , Cardiopatias/metabolismo , Cardiopatias/patologia , Hiperlipidemias/sangue , Hiperlipidemias/enzimologia , Hiperlipidemias/genética , Indolamina-Pirrol 2,3,-Dioxigenase/genética , Indolamina-Pirrol 2,3,-Dioxigenase/metabolismo , Inflamação/enzimologia , Inflamação/metabolismo , Inflamação/patologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Knockout , Pancreatite/induzido quimicamente , Pancreatite/enzimologia , Pancreatite/genética , Caracteres Sexuais
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