Issue 1 - "Update on adverse respiratory effects of outdoor air pollution" Part 2): Outdoor air pollution and respiratory diseases: Perspectives from Angola, Brazil, Canada, Iran, Mozambique and Portugal.

OBJECTIVE: To analyse the GARD perspective on the health effects of outdoor air pollution, and to synthesise the Portuguese epidemiological contribution to knowledge on its respiratory impact. RESULTS: Ambient air pollution has deleterious respiratory effects which are more apparent in larger, densely populated and industrialised countries, such as Canada, Iran, Brazil and Portugal, but it also affects people living in low-level exposure areas. While low- and middle-income countries (LMICs), are particularly affected, evidence based on epidemiological studies from LMICs is both limited and heterogeneous. While nationally, Portugal has a relatively low level of air pollution, many major cities face with substantial air pollution problems. Time series and cross-sectional epidemiological studies have suggested increased respiratory hospital admissions, and increased risk of respiratory diseases in people who live in urban areas and are exposed to even a relatively low level of air pollution. CONCLUSIONS: Adverse respiratory effects due to air pollution, even at low levels, have been confirmed by epidemiological studies. However, evidence from LMICs is heterogeneous and relatively limited. Furthermore, longitudinal cohort studies designed to study and quantify the link between exposure to air pollutants and respiratory diseases are needed. Worldwide, an integrated approach must involve multi-level stakeholders including governments (in Portugal, the Portuguese Ministry of Health, which hosts GARD-Portugal), academia, health professionals, scientific societies, patient associations and the community at large. Such an approach not only will garner a robust commitment, establish strong advocacy and clear objectives, and raise greater awareness, it will also support a strategy with adequate measures to be implemented to achieve better air quality and reduce the burden of chronic respiratory diseases (CRDs).

Emerging new avian reovirus variants from cases of enteric disorders and arthritis/tenosynovitis in Brazilian poultry flocks.

1. The objective of this study was to characterise circulating Brazilian avian reovirus (ARV) strains by genetic analysis of the σC protein encoded by segment 1 of the viral genome and compare these with those of viral strains used for immunising commercial poultry.2. The analysis detected the presence of ARV genomes by quantitative reverse transcriptase PCR (RT-qPCR) in the enteric samples and the joint tissues (JT) of birds with signs of viral arthritis/tenosynovitis. Nucleotide sequencing used 16 strains (three commercial vaccines, 10 from enteric tissues and three from JT). The results indicated high variability in the amino acid sequences of 13 wild strains, showing between 40% and 75% similarity compared with the vaccine strains (S1133 and 2177).3. The sequences were grouped into three well-defined clusters in a phylogenetic tree, two of these clusters together with previous Brazilian σC ARV sequences, and one cluster (VII) that was novel for Brazilian strains. Antigenic analysis showed that there were amino acids within putative epitopes located on the surface of the receptor-binding region of the σC protein with a high degree of variability.4. The study confirmed the presence of ARV genetic variants circulating in commercial birds in Brazil, and according to the antigenic prediction, the possibility of antigenic variants appears to be high.

Molecular diagnostic of chicken parvovirus (ChPV) affecting broiler flocks in Ecuador

Enteric diseases affect poultry and cause important economic losses in many countries worldwide. Avian parvovirus has been linked to enteric conditions, such as malabsorption and runting-stunting syndrome (RSS), characterized by diarrhoea, and reduced weight gain and growth retardation. In 2013 and 2016, 79 samples were collected from different organs of chickens in Ecuador that exhibited signs of diarrhea and stunting syndrome, and analysed for the presence of chicken parvovirus (ChPV). The detection method of ChPV applied was Polymerase Chain Reaction (PCR), using primers designed from the conserved region of the viral genome that encodes the non-structural protein NS1. Out of the 79 samples, 50.6% (40/79) were positive for ChPV, and their nucleotide and amino acid sequences were analysed to determine their phylogenetic relationship with the sequences reported in the United States, Canada, China, South Korea, Croatia, Poland, Hungary, and Brazil. Strong similarity of nucleotide and amino acid sequences among all analyzed sequences and between the analysed and reference sequences was demonstrated, and the phylogenetic analysis clustered all the sequences within the same group, demonstrating a strong relation between the studied strains and the reference chicken parvovirus strains.(AU)

Molecular diagnostic of chicken parvovirus (ChPV) affecting broiler flocks in Ecuador

Enteric diseases affect poultry and cause important economic losses in many countries worldwide. Avian parvovirus has been linked to enteric conditions, such as malabsorption and runting-stunting syndrome (RSS), characterized by diarrhoea, and reduced weight gain and growth retardation. In 2013 and 2016, 79 samples were collected from different organs of chickens in Ecuador that exhibited signs of diarrhea and stunting syndrome, and analysed for the presence of chicken parvovirus (ChPV). The detection method of ChPV applied was Polymerase Chain Reaction (PCR), using primers designed from the conserved region of the viral genome that encodes the non-structural protein NS1. Out of the 79 samples, 50.6% (40/79) were positive for ChPV, and their nucleotide and amino acid sequences were analysed to determine their phylogenetic relationship with the sequences reported in the United States, Canada, China, South Korea, Croatia, Poland, Hungary, and Brazil. Strong similarity of nucleotide and amino acid sequences among all analyzed sequences and between the analysed and reference sequences was demonstrated, and the phylogenetic analysis clustered all the sequences within the same group, demonstrating a strong relation between the studied strains and the reference chicken parvovirus strains.

New records of helminths in reptiles from five states of Brazil / Novos registros de helmintos em répteis de cinco estados do Brasil

Forty five specimens representing nine species of reptile (Salvator merianae, Enyalius bilineatus, Amphisbaena alba, Xenopholis undulatus, Chironius fuscus, Helicops angulatus, Chironius flavolineatus, Erythrolamprus viridis and Crotalus durissus) collected in five Brazilian states were examined for helminths. Twelve helminth species were found as follow: nine Nematoda (Physaloptera tupinambae, Strongyluris oscari, Paracapillaria sp., Dracunculus brasiliensis, Physaloptera liophis, Serpentirhabias sp. 1, Serpentirhabias sp. 2, Serpentirhabias sp. 3 and Aplectana sp.), one Cestoda (Semenoviella amphisbaenia), one Trematoda (Paracotyletrema sp.), and one Acantocephala (Centrorhynchus sp.). Ten new host records and seven new locality records were reported.(AU)

Quarenta e cinco espécimes que representa nove espécies de répteis (Salvator merianae, Enyalius bilineatus, Amphisbaena alba, Xenopholis undulatus, Chironius fuscus, Helicops angulatus, Chironius flavolineatus, Erythrolamprus viridis e Crotalus durissus) coletados em cinco estados brasileiros foram examinados para helmintos. Foram encontrados doze espécies de helmintos sendo: nove Nematoda (Physaloptera tupinambae, Strongyluris oscari, Paracapillaria sp., Dracunculus brasiliensis, Physaloptera liophis, Serpentirhabias sp. 1, Serpentirhabias sp. 2, Serpentirhabias sp. 3 e Aplectana sp.), um Cestoda (Semenoviella amphisbaenia), um Trematoda (Paracotyletrema sp.) e um Acantocephala (Centrorhynchus sp.). Dez novos registros de hospedeiros e sete novos registros de localidade foram relatados.(AU)

New records of Helminths in Reptiles from five states of Brazil / Novos registros de helmintos em répteis de cinco estados do Brasil

Abstract Forty five specimens representing nine species of reptile (Salvator merianae, Enyalius bilineatus, Amphisbaena alba, Xenopholis undulatus, Chironius fuscus, Helicops angulatus, Chironius flavolineatus, Erythrolamprus viridis and Crotalus durissus) collected in five Brazilian states were examined for helminths. Twelve helminth species were found as follow: nine Nematoda (Physaloptera tupinambae, Strongyluris oscari, Paracapillaria sp., Dracunculus brasiliensis, Physaloptera liophis, Serpentirhabias sp. 1, Serpentirhabias sp. 2, Serpentirhabias sp. 3 and Aplectana sp.), one Cestoda (Semenoviella amphisbaenia), one Trematoda (Paracotyletrema sp.), and one Acantocephala (Centrorhynchus sp.). Ten new host records and seven new locality records were reported.

Resumo Quarenta e cinco espécimes que representa nove espécies de répteis (Salvator merianae, Enyalius bilineatus, Amphisbaena alba, Xenopholis undulatus, Chironius fuscus, Helicops angulatus, Chironius flavolineatus, Erythrolamprus viridis e Crotalus durissus) coletados em cinco estados brasileiros foram examinados para helmintos. Foram encontrados doze espécies de helmintos sendo: nove Nematoda (Physaloptera tupinambae, Strongyluris oscari, Paracapillaria sp., Dracunculus brasiliensis, Physaloptera liophis, Serpentirhabias sp. 1, Serpentirhabias sp. 2, Serpentirhabias sp. 3 e Aplectana sp.), um Cestoda (Semenoviella amphisbaenia), um Trematoda (Paracotyletrema sp.) e um Acantocephala (Centrorhynchus sp.). Dez novos registros de hospedeiros e sete novos registros de localidade foram relatados.

Detection by Rt-Pcr and Molecular Characterization of Tremovirus A Obtained from Clinical Cases of Avian Encephalomyelitis (AE) Outbreaks in Brazil

This study determined the presence of Tremovirus A as the possible agent related to Avian Encephalomyelitis in broiler chicks from the states of São Paulo (SP) Paraná (PR), Goiás (GO), Santa Catarina (SC) and Rio Grande do Sul (RS), between the years 2006 and 2015. Samples of the nervous, digestive, respiratory, immune, and renal systems, plus muscular organs from broiler chicks with neurological problems such as ataxia and muscle tremors, and four (4) commercial vaccines as positive control, were tested by reverse-transcriptase (RT-PCR) amplification and DNA sequencing. A highly conserved region (P1) of the viral genome, was used to amplify a segment which encodes a structural protein VP4. Out of 112 samples, 46 were positive (42%) for Tremovirus A, that was identified in the nervous, digestive, respiratory, renal and immune systems. The phylogenetic analysis clustered together the nucleotide sequences of the 46 samples, the four commercial vaccine strains and the reference sequence of Calnek strain obtained from the GenBank. According to these results, we conclude that the presence of Tremovirus A in these Brazilian chicken flocks distributed in all states was due to flaws in the biosecurity measurements.(AU)

Detection by Rt-Pcr and Molecular Characterization of Tremovirus A Obtained from Clinical Cases of Avian Encephalomyelitis (AE) Outbreaks in Brazil

This study determined the presence of Tremovirus A as the possible agent related to Avian Encephalomyelitis in broiler chicks from the states of São Paulo (SP) Paraná (PR), Goiás (GO), Santa Catarina (SC) and Rio Grande do Sul (RS), between the years 2006 and 2015. Samples of the nervous, digestive, respiratory, immune, and renal systems, plus muscular organs from broiler chicks with neurological problems such as ataxia and muscle tremors, and four (4) commercial vaccines as positive control, were tested by reverse-transcriptase (RT-PCR) amplification and DNA sequencing. A highly conserved region (P1) of the viral genome, was used to amplify a segment which encodes a structural protein VP4. Out of 112 samples, 46 were positive (42%) for Tremovirus A, that was identified in the nervous, digestive, respiratory, renal and immune systems. The phylogenetic analysis clustered together the nucleotide sequences of the 46 samples, the four commercial vaccine strains and the reference sequence of Calnek strain obtained from the GenBank. According to these results, we conclude that the presence of Tremovirus A in these Brazilian chicken flocks distributed in all states was due to flaws in the biosecurity measurements.

New records of Helminths in Reptiles from five states of Brazil.

Forty five specimens representing nine species of reptile (Salvator merianae, Enyalius bilineatus, Amphisbaena alba, Xenopholis undulatus, Chironius fuscus, Helicops angulatus, Chironius flavolineatus, Erythrolamprus viridis and Crotalus durissus) collected in five Brazilian states were examined for helminths. Twelve helminth species were found as follow: nine Nematoda (Physaloptera tupinambae, Strongyluris oscari, Paracapillaria sp., Dracunculus brasiliensis, Physaloptera liophis, Serpentirhabias sp. 1, Serpentirhabias sp. 2, Serpentirhabias sp. 3 and Aplectana sp.), one Cestoda (Semenoviella amphisbaenia), one Trematoda (Paracotyletrema sp.), and one Acantocephala (Centrorhynchus sp.). Ten new host records and seven new locality records were reported.

Epidemiology of avian infectious laryngotracheitis with special focus to south america: an update

Avian Infectious laryngotracheitis (AILT) is a respiratory tract disease of great importance because it causes significant economic losses in the poultry industry around the world. It is caused by a Gallid herpesvirus type 1, a member of the genus Iltovirus. The target system for Avian Infectious Laryngotracheitis virus (AILTV) infections is the respiratory system, and the main organ in which the virus remains latent is the trigeminal ganglia. However, the virus has demonstrated tropism for other organs besides the respiratory tract. The main transmission routes are ocular and respiratory. Infected birds with clinical symptoms are main sources of transmission, but birds with latent infections, litter, and contaminated fomites may also transmit the virus. Clinical signs usually appear 6-12 days after natural exposure and may be moderate or severe. The causative agent of this disease can be propagated in chorioallantoic membrane (CAM) of developing chicken embryos and replicate in mature chicken kidney cells, as well as in a variety of epithelial chick embryo cells, such as kidneys, liver and lungs. There are several procedures for the diagnosis of ILT such as the observation of clinical signs, the detection of gross and histopathological lesions, and the use of molecular techniques, including RFLP, polymerase chain reaction (PCR), real-time PCR, and loop-mediated isothermal amplification. Vaccination with different types of vaccine provides a good expectation on disease control, such as vaccines produced in chicken-embryo-origin (CEO), tissue-culture-origin (TCO), and recombinant vaccines. However, in endemic areas, biosecurity measures and best management practices are important for the control of the disease. It is distributed worldwide and, in South America, it has been reported in Brazil, Peru, Ecuador, Bolivia, and Argentina causing great economic losses.(AU)

Epidemiology of avian infectious laryngotracheitis with special focus to south america: an update

Avian Infectious laryngotracheitis (AILT) is a respiratory tract disease of great importance because it causes significant economic losses in the poultry industry around the world. It is caused by a Gallid herpesvirus type 1, a member of the genus Iltovirus. The target system for Avian Infectious Laryngotracheitis virus (AILTV) infections is the respiratory system, and the main organ in which the virus remains latent is the trigeminal ganglia. However, the virus has demonstrated tropism for other organs besides the respiratory tract. The main transmission routes are ocular and respiratory. Infected birds with clinical symptoms are main sources of transmission, but birds with latent infections, litter, and contaminated fomites may also transmit the virus. Clinical signs usually appear 6-12 days after natural exposure and may be moderate or severe. The causative agent of this disease can be propagated in chorioallantoic membrane (CAM) of developing chicken embryos and replicate in mature chicken kidney cells, as well as in a variety of epithelial chick embryo cells, such as kidneys, liver and lungs. There are several procedures for the diagnosis of ILT such as the observation of clinical signs, the detection of gross and histopathological lesions, and the use of molecular techniques, including RFLP, polymerase chain reaction (PCR), real-time PCR, and loop-mediated isothermal amplification. Vaccination with different types of vaccine provides a good expectation on disease control, such as vaccines produced in chicken-embryo-origin (CEO), tissue-culture-origin (TCO), and recombinant vaccines. However, in endemic areas, biosecurity measures and best management practices are important for the control of the disease. It is distributed worldwide and, in South America, it has been reported in Brazil, Peru, Ecuador, Bolivia, and Argentina causing great economic losses.

Surveillance for Newcastle disease virus, Avian influenza virus and Mycoplasma gallisepticum in wild birds near commercial poultry farms surrounded by Atlantic rainforest remnants, Southeastern Brazil

The geographic overlap between areas of Atlantic rainforest and human activities allows interactions to occur between humans and wild and domestic animals. Despite the great importance of the domestic animal-wildlife-human interface that occurs at poultry farms in terms of public health, economic production and wildlife conservation, there are few studies in Brazil examining the distribution and health of wild birds that interact with poultry farms. From January to December 2010, mist nets were used to capture 166 free-ranging birds that were within close proximity to three poultry farms in Atlantic rainforest remnants in south-eastern Brazil. The species composition was examined, and molecular methods were used to test for avian influenza virus, Newcastle disease virus, and Mycoplasma gallisepticum. The avian communities near the poultry farms were dominated by three synanthropic species, which corresponded to 70% of all captured individuals: house sparrows Passer domesticus (33%), saffron finches (Sicalis flaveola) (22%), and ruddy ground-doves (Columbina talpacoti) (15%). These predominant bird species were in poor body condition (27%), were infested with feather mites (43%), or presented both conditions (23%). No evidence of infection by avian influenza virus, Newcastle disease virus or M. gallisepticum was identified in any of the studied birds. Although no evidence of the studied pathogens was, our findings demonstrate that differences in the environmental characteristics and biosecurity practices influence the wild bird community near poultry farms, which in turn may affect the health status of these synanthropic birds and strengthen their role in the transmission of pathogens.(AU)

Surveillance for Newcastle disease virus, Avian influenza virus and Mycoplasma gallisepticum in wild birds near commercial poultry farms surrounded by Atlantic rainforest remnants, Southeastern Brazil

The geographic overlap between areas of Atlantic rainforest and human activities allows interactions to occur between humans and wild and domestic animals. Despite the great importance of the domestic animal-wildlife-human interface that occurs at poultry farms in terms of public health, economic production and wildlife conservation, there are few studies in Brazil examining the distribution and health of wild birds that interact with poultry farms. From January to December 2010, mist nets were used to capture 166 free-ranging birds that were within close proximity to three poultry farms in Atlantic rainforest remnants in south-eastern Brazil. The species composition was examined, and molecular methods were used to test for avian influenza virus, Newcastle disease virus, and Mycoplasma gallisepticum. The avian communities near the poultry farms were dominated by three synanthropic species, which corresponded to 70% of all captured individuals: house sparrows Passer domesticus (33%), saffron finches (Sicalis flaveola) (22%), and ruddy ground-doves (Columbina talpacoti) (15%). These predominant bird species were in poor body condition (27%), were infested with feather mites (43%), or presented both conditions (23%). No evidence of infection by avian influenza virus, Newcastle disease virus or M. gallisepticum was identified in any of the studied birds. Although no evidence of the studied pathogens was, our findings demonstrate that differences in the environmental characteristics and biosecurity practices influence the wild bird community near poultry farms, which in turn may affect the health status of these synanthropic birds and strengthen their role in the transmission of pathogens.

Detection and molecular characterization of chicken astrovirus associated with chicks that have an unusual condition known as "white chicks" in Brazil.

Chicken astrovirus (CAstV) is one of many viruses related to enteric diseases in poultry that are associated with Runting-Stunting Syndrome (RSS), which affects young chickens. CAstV was also recently associated with an unusual condition in chicks called "white chicks." Some hatcheries in certain states of Brazil have reported several incubation problems, mortality, and the presence of chicks with white plumages over the past several months. These chicks were termed locally as "white chicks." The present work investigated 30 chicks with this unusual condition using a multidisciplinary approach. Postmortem examination of each chick showed enlarged livers and intestines that were full of liquid and gas (30/30). The pancreas, kidneys, and spleen were pale (30/30). The other organs did not show any macroscopic alterations. CAstV, chicken parvovirus (ChPV), avian nephritis virus (ANV), avian rotavirus (ARtV), avian reovirus (AReoV), infectious bronchitis virus (IBV), and fowl adenovirus group I (FAdV-1) were tested in the intestines, pancreas, proventriculus, gizzard, liver, spleen, bursa, kidneys, thymus, lung, heart, brain, and yolk sac in each chick. All organs and yolk sacs were positive for CAstV in different titres and negative for the other tested viruses. The partial molecular characterization of the ORF 1b gene of CAstV using 28 sequences revealed a high similarity of the nucleotides and amino acids with sequences of CAstV from North America, Europe, and Asia, and our CAstV sequences clustered into a unique group that was separate from the other sequences. These results demonstrated that CAstV was associated with the white chick condition in Brazil. The virus was distributed in most organs, including the brain and yolk sac. These results suggest that the virus could be transmitted vertically. The molecular characterization also revealed that the CAstV associated with white chick condition was molecularly related to other CAstV sequences found worldwide.

Molecular detection of chicken parvovirus in broilers with enteric disorders presenting curving of duodenal loop, pancreatic atrophy, and mesenteritis.

Enteric disorders are an important cause of economic losses in broiler chickens worldwide. Several agents have been associated with enteric problems, such as viruses, bacteria, and parasites. In this study, broiler chickens showing signs of enteric disorders were subjected to molecular diagnosis for several viral agents and also for pathological examination for elucidating this problem. Thus, the chickens were screened for avian nephritis virus (ANV), chicken astrovirus (CAstV), avian rotavirus (ArtV), avian reovirus (AReoV), infectious bronchitis virus (IBV), fowl adenovirus group I (FAdV-1), and chicken parvovirus (ChPV). Postmortem examinations revealed a curving of the duodenal loop (J-like appearance) and intestines filled with liquid and gaseous content. Histopathological analysis of the duodenal loop showed pancreatic atrophy, acute mesenteritis, and enteritis. PCR results showed that ChPV was the sole viral agent detected in samples with lesions such as the curved duodenal loop and pancreatic atrophy. Molecular characterization of the nucleotide and deduced amino acid sequences revealed a high similarity with other strains of ChPV from Brazil, Canada, United States, Europe, and Asia. These findings suggest an association between ChPV and the development of enteritis, pancreatitis, and pancreatic atrophy, which may lead to curling of the duodenal loop. Together, these alterations may disrupt the normal functioning of the digestive system, diminishing digestion and the absorption of dietary nutrients and consequently leading to reduced weight gain, flock impairment, dwarfism, and an elevated feed conversion rate.

Virulence and antimicrobial resistance of Klebsiella pneumoniae isolated from passerine and psittacine birds.

Klebsiella pneumoniae is considered one of the most important Gram-negative opportunistic pathogens. The contact between humans and birds poses health risks to both. The aim of this study was to investigate the resistance and virulence of K. pneumoniae isolates from psittacines and passerines, seized from illegal trade in Brazil. We analysed 32 strains isolated from birds of the orders Psittaciformes and Passeriformes by polymerase chain reaction (PCR) for virulence factor genes. Antibiotic resistance was assessed by disk diffusion assay and PCR. The results indicated that fimH (100%), uge (96.8%), kfu (81.2%) and irp-2 (68.7%) were the most common virulence genes, followed by kpn (46.8%), K2 (43.7%), mrkD (34.3%) and iroN (15.6%). The combination of virulence genes resulted in a great diversity of genotypes and the heterogeneity of the strains is also confirmed in the analysis by amplified fragment length polymorphism. The susceptibility profiles of the K. pneumoniae showed 25% of multiple antibiotic resistance strains. We identified seven strains that presented non-extended spectrum beta lactamase blaSHV variants SHV-1 and SHV-11 and one strain positive to the blaTEM-1 gene. Plasmid-mediated quinolone resistance was present in 10 strains (10/32). The data obtained in this study reveal the pathogenic potential of this pathogen and highlight the need for surveillance and monitoring.

Single-walled carbon nanotubes functionalized with sodium hyaluronate enhance bone mineralization.

The aim of this study was to evaluate the effects of sodium hyaluronate (HY), single-walled carbon nanotubes (SWCNTs) and HY-functionalized SWCNTs (HY-SWCNTs) on the behavior of primary osteoblasts, as well as to investigate the deposition of inorganic crystals on titanium surfaces coated with these biocomposites. Primary osteoblasts were obtained from the calvarial bones of male newborn Wistar rats (5 rats for each cell extraction). We assessed cell viability using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide assay and by double-staining with propidium iodide and Hoechst. We also assessed the formation of mineralized bone nodules by von Kossa staining, the mRNA expression of bone repair proteins, and the deposition of inorganic crystals on titanium surfaces coated with HY, SWCNTs, or HY-SWCNTs. The results showed that treatment with these biocomposites did not alter the viability of primary osteoblasts. Furthermore, deposition of mineralized bone nodules was significantly increased by cells treated with HY and HY-SWCNTs. This can be partly explained by an increase in the mRNA expression of type I and III collagen, osteocalcin, and bone morphogenetic proteins 2 and 4. Additionally, the titanium surface treated with HY-SWCNTs showed a significant increase in the deposition of inorganic crystals. Thus, our data indicate that HY, SWCNTs, and HY-SWCNTs are potentially useful for the development of new strategies for bone tissue engineering.

Dexamethasone Regulates Macrophage and Cd4+Cd25+ Cell Numbers in the Chicken Spleen

Dexamethasone (DEX) is a corticoid hormone that is experimentally used to mimic the effects of increased levels of endogenous corticosterone observed during the stress response. Currently, stress is considered one of the major predisposing factors for diseases in the poultry industry. The aim of this study was to analyze the effects of DEX and/or of a 20-fold coccidial vaccine dose on leukocyte phenotypes in the spleen and cecal tonsils of chickens. Twenty specific-pathogen-free (SPF) Leghorn chickens were divided into four groups: a non-treated group (NT), a DEX-treated group (Dex), a vaccinated group (V) and a DEX-treated+vaccinated group (Dex+V). On experimental day (ED) 42, each bird in the vaccinated groups received a anti-coccidial vaccine. DEX was injected in the birds of the Dex and Dex+V groups (0.9 mg/kg) onED42 and ED45. The immunophenotyping was performed by flow cytometry analysis of splenocytes and cecal tonsils cells onED48. DEX treatment per se was unable to change CD4+CD8+, CD4+CD8+ and CD4-CD8+ populations with TCRgd or CD28 in the spleen, or macrophages and T lymphocytes in the cecal tonsils. V group birds presented higher numbers of splenic macrophages compared with those measured in the Dex+V group. The number of CD4+CD25+ cells in the spleen of birds of the V group was higher than those measured in the other experimental groups. Our data suggest that CD4+CD25+ cells and macrophages might be influenced by DEX treatment in spleen, but not in the cecal tonsils of chickens inoculated with Eimeria.(AU)

Dexamethasone Regulates Macrophage and Cd4+Cd25+ Cell Numbers in the Chicken Spleen

Dexamethasone (DEX) is a corticoid hormone that is experimentally used to mimic the effects of increased levels of endogenous corticosterone observed during the stress response. Currently, stress is considered one of the major predisposing factors for diseases in the poultry industry. The aim of this study was to analyze the effects of DEX and/or of a 20-fold coccidial vaccine dose on leukocyte phenotypes in the spleen and cecal tonsils of chickens. Twenty specific-pathogen-free (SPF) Leghorn chickens were divided into four groups: a non-treated group (NT), a DEX-treated group (Dex), a vaccinated group (V) and a DEX-treated+vaccinated group (Dex+V). On experimental day (ED) 42, each bird in the vaccinated groups received a anti-coccidial vaccine. DEX was injected in the birds of the Dex and Dex+V groups (0.9 mg/kg) onED42 and ED45. The immunophenotyping was performed by flow cytometry analysis of splenocytes and cecal tonsils cells onED48. DEX treatment per se was unable to change CD4+CD8+, CD4+CD8+ and CD4-CD8+ populations with TCRgd or CD28 in the spleen, or macrophages and T lymphocytes in the cecal tonsils. V group birds presented higher numbers of splenic macrophages compared with those measured in the Dex+V group. The number of CD4+CD25+ cells in the spleen of birds of the V group was higher than those measured in the other experimental groups. Our data suggest that CD4+CD25+ cells and macrophages might be influenced by DEX treatment in spleen, but not in the cecal tonsils of chickens inoculated with Eimeria.

Single-walled carbon nanotubes functionalized with sodium hyaluronate enhance bone mineralization

The aim of this study was to evaluate the effects of sodium hyaluronate (HY), single-walled carbon nanotubes (SWCNTs) and HY-functionalized SWCNTs (HY-SWCNTs) on the behavior of primary osteoblasts, as well as to investigate the deposition of inorganic crystals on titanium surfaces coated with these biocomposites. Primary osteoblasts were obtained from the calvarial bones of male newborn Wistar rats (5 rats for each cell extraction). We assessed cell viability using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide assay and by double-staining with propidium iodide and Hoechst. We also assessed the formation of mineralized bone nodules by von Kossa staining, the mRNA expression of bone repair proteins, and the deposition of inorganic crystals on titanium surfaces coated with HY, SWCNTs, or HY-SWCNTs. The results showed that treatment with these biocomposites did not alter the viability of primary osteoblasts. Furthermore, deposition of mineralized bone nodules was significantly increased by cells treated with HY and HY-SWCNTs. This can be partly explained by an increase in the mRNA expression of type I and III collagen, osteocalcin, and bone morphogenetic proteins 2 and 4. Additionally, the titanium surface treated with HY-SWCNTs showed a significant increase in the deposition of inorganic crystals. Thus, our data indicate that HY, SWCNTs, and HY-SWCNTs are potentially useful for the development of new strategies for bone tissue engineering.