H9N2 avian influenza virus dispersal along Bangladeshi poultry trading networks.

Avian influenza virus subtype H9N2 is endemic in Bangladesh's poultry population. The subtype affects poultry production and poses a potential zoonotic risk. Insufficient understanding of how the poultry trading network shapes the dissemination of avian influenza viruses has hindered the design of targeted interventions to reduce their spread. Here, we use phylodynamic analyses of haemagglutinin sequences to investigate the spatial spread and dispersal patterns of H9N2 viruses in Bangladesh's poultry population, focusing on its two largest cities (Dhaka and Chattogram) and their poultry production and distribution networks. Our analyses suggest that H9N2 subtype avian influenza virus lineage movement occurs relatively less frequently between Bangladesh's two largest cities than within each city. H9N2 viruses detected in single markets are often more closely related to viruses from other markets in the same city than to each other, consistent with close epidemiological connectivity between markets. Our analyses also suggest that H9N2 viruses may spread more frequently between chickens of the three most commonly sold types (sunali-a cross-bred of Fayoumi hen and Rhode Island Red cock, deshi-local indigenous, and exotic broiler) in Dhaka than in Chattogram. Overall, this study improves our understanding of how Bangladesh's poultry trading system impacts avian influenza virus spread and should contribute to the design of tailored surveillance that accommodates local heterogeneity in virus dispersal patterns.

Altered serotonin (5-HT) 1D and 2A receptor expression may contribute to defective insulin and glucagon secretion in human type 2 diabetes.

Islet produced 5-hydroxy tryptamine (5-HT) is suggested to regulate islet hormone secretion in a paracrine and autocrine manner in rodents. Hitherto, no studies demonstrate a role for this amine in human islet function, nor is it known if 5-HT signaling is involved in the development of beta cell dysfunction in type 2 diabetes (T2D). To clarify this, we performed a complete transcriptional mapping of 5-HT receptors and processing enzymes in human islets and investigated differential expression of these genes in non-diabetic and T2D human islet donors. We show the expression of fourteen 5-HT receptors as well as processing enzymes involved in the biosynthesis of 5-HT at the mRNA level in human islets. Two 5-HT receptors (HTR1D and HTR2A) were over-expressed in T2D islet donors. Both receptors (5-HT1d and 5-HT2a) were localized to human alpha, beta and delta cells. 5-HT inhibited both insulin and glucagon secretion in non-diabetic islet donors. In islets isolated from T2D donors the amine significantly increased release of insulin in response to glucose. Our results suggest that 5-HT signaling participates in regulation of overall islet hormone secretion in non- diabetic individuals and over-expression of HTR1D and HTR2A may either contribute to islet dysfunction in T2D or arise as a consequence of an already dysfunctional islet.

Workplace bullying: an emergent issue.

All companies, including dentists, rely on their staff to represent their firms in the most positive and effective manner. Today's managers face a multitude of issues, and as such, they must walk a fine line of fostering a productive, harmonious and safe working environment for their employees. Over the last several decades it is apparent that on the- job sexual harassment is no longer the leading issue of employee complaints. Rather, the organization issue which was investigated is workplace bullying, also commonly referred to as employee harassment. Risk management is no longer limited to avoiding malpractice issues but also preventing litigation created by poor organizational behavior. The primary purpose of this paper is to explore the background of workplace bullying and how it affects today's managers and their employees, customers and suppliers. In other words, the scope of this paper will feature research on past studies, results and conclusions. Since workplace bullying affects all levels of a corporation, it must be stated that the concern and focus of this paper is for today's manager to understand the background and history of workplace bullying, and what they can do to foster a safe working environment and prevent the bully from creating mental and physical harm to their employees. This paper details the history of workplace bullying and how management, employees and suppliers deal with and address the issue. Lastly, this treatise looks at risk management from a manger/dentist's perspective, the assessment/conclusion summarizes the implications for managers regarding how they must handle the issue or risk harm to the employee and/or serious legal ramifications.

First reported detection of a low pathogenicity avian influenza virus subtype H9 infection in domestic fowl in England.

In December 2010, infection with a H9N1 low pathogenicity avian influenza (LPAI) virus was detected in a broiler breeder flock in East Anglia. Disease suspicion was based on acute drops in egg production in two of four sheds on the premises, poor egg shell quality and evidence of diarrhoea. H9N1 LPAI virus infection was confirmed by real-time reverse transcription PCR. Sequencing revealed high nucleotide identity of 93.6 per cent and 97.9 per cent with contemporary North American H9 and Eurasian N1 genes, respectively. Attempted virus isolation in embryonated specific pathogen free (SPF) fowls' eggs was unsuccessful. Epidemiological investigations were conducted to identify the source of infection and any onward spread. These concluded that infection was restricted to the affected premises, and no contacts or movements of poultry, people or fomites could be attributed as the source of infection. However, the infection followed a period of extremely cold weather and snow which impacted on the biosecurity protocols on site, and also led to increased wild bird activity locally, including waterfowl and game birds around the farm buildings. Analysis of the N1 gene sequence suggested direct introduction from wild birds. Although H9 infection in poultry is not notifiable, H9N2 LPAI viruses have been associated with production and mortality episodes in poultry in many parts of Asia and the Middle East. In the present H9N1 outbreak, clinical signs were relatively mild in the poultry with no mortality, transient impact on egg production and no indication of zoonotic spread. However, this first reported detection of H9 LPAI virus in chickens in England was also the first H9 UK poultry case for 40 years, and vindicates the need for continued vigilance and surveillance of avian influenza viruses in poultry populations.

Descriptive clinical and epidemiological characteristics of influenza A H1N1 2009 virus infections in pigs in England.

Infection of pigs with influenza A H1N1 2009 virus (A(H1N1)pdm09) was first detected in England in November 2009 following global spread of the virus in the human population. This paper describes clinical and epidemiological findings in the first English pig farms in which A(H1N1)pdm09 influenza virus was detected. These farms showed differences in disease presentation, spread and duration of infection. The factors likely to influence these features are described and relate to whether pigs were housed or outdoors, the age of the pigs, inter-current disease and the management system of the unit. Infection could be mild or clinically inapparent in breeding pigs with more typical respiratory disease being identified later in their progeny. Mortality was low where disease was uncomplicated by environmental stresses or concurrent infections. Where deaths occurred in pigs infected with A(H1N1)pdm09 influenza, they were mainly due to other infections, including streptococcal disease due to Streptococcus suis infection. This paper demonstrates the ease with which A(H1N1)pdm09 virus was transmitted horizontally and maintained in a pig population.

Digital imaging in dentistry.

Information technology is vital to operations, marketing, accounting, finance and administration. One of the most exciting and quickly evolving technologies in the modern dental office is digital applications. The dentist is often the business manager, information technology officer and strategic planning chief for his small business. The information systems triangle applies directly to this critical manager supported by properly trained ancillary staff and good equipment. With emerging technology driving all medical disciplines and the rapid pace at which it emerges, it is vital for the contemporary practitioner to keep abreast of the newest information technology developments. This article compares the strategic and operational advantages of digital applications, specifically imaging. The focus of this paper will be on digital radiography (DR), 3D computerized tomography, digital photography and digitally-driven CAD/CAM to what are now considered obsolescing modalities and contemplates what may arrive in the future. It is the purpose of this essay to succinctly evaluate the decisions involved in the role, application and implications of employing this tool in the dental environment

Virological surveillance and preliminary antigenic characterization of influenza viruses in pigs in five European countries from 2006 to 2008.

This study presents the results of the virological surveillance for swine influenza viruses (SIVs) in Belgium, UK, Italy, France and Spain from 2006 to 2008. Our major aims were to clarify the occurrence of the three SIV subtypes - H1N1, H3N2 and H1N2 - at regional levels, to identify novel reassortant viruses and to antigenically compare SIVs with human H1N1 and H3N2 influenza viruses. Lung tissue and/or nasal swabs from outbreaks of acute respiratory disease in pigs were investigated by virus isolation. The hemagglutinin (HA) and neuraminidase (NA) subtypes were determined using standard methods. Of the total 169 viruses, 81 were classified as 'avian-like' H1N1, 36 as human-like H3N2 and 47 as human-like H1N2. Only five novel reassortant viruses were identified: two H1N1 viruses had a human-like HA and three H1N2 viruses an avian-like HA. All three SIV subtypes were detected in Belgium, Italy and Spain, while only H1N1 and H1N2 viruses were found in UK and Northwestern France. Cross-hemagglutination inhibition (HI) tests with hyperimmune sera against selected older and recent human influenza viruses showed a strong antigenic relationship between human H1N1 and H3N2 viruses from the 1980s and H1N2 and H3N2 human-like SIVs, confirming their common origin. However, antisera against human viruses isolated during the last decade did not react with currently circulating H1 or H3 SIVs, suggesting that especially young people may be, to some degree, susceptible to SIV infections.

Initial incursion of pandemic (H1N1) 2009 influenza A virus into European pigs.

The initial incursion of pandemic (H1N1) 2009 influenza A virus (pH1N1) into a European pig population is reported. Diagnosis of swine influenza caused by pandemic virus was made during September 2009 following routine submission of samples for differential diagnosis of causative agents of respiratory disease, including influenza A virus. All four pigs (aged six weeks) submitted for investigation from a pig herd of approximately 5000 animals in Northern Ireland, experiencing acute-onset respiratory signs in finishing and growing pigs, were positive by immunofluorescence for influenza A. Follow-up analysis of lung tissue homogenates by real-time RT-PCR confirmed the presence of pH1N1. The virus was subsequently detected on two other premises in Northern Ireland; on one premises, detection followed the pre-export health certification testing of samples from pigs presumed to be subclinically infected as no clinical signs were apparent. None of the premises was linked to another epidemiologically. Sequencing of the haemagglutinin and neuraminidase genes revealed high nucleotide identity (>99.4 per cent) with other pH1N1s isolated from human beings. Genotypic analyses revealed all gene segments to be most closely related to those of contemporary pH1N1 viruses in human beings. It is concluded that all three outbreaks occurred independently, potentially as a result of transmission of the virus from human beings to pigs.

Toll-like receptor 2 is upregulated by hog confinement dust in an IL-6-dependent manner in the airway epithelium.

Hog confinement workers are at high risk to develop chronic bronchitis as a result of their exposure to organic dust. Chronic bronchitis is characterized by inflammatory changes of the airway epithelium. A key mediator in inflammation is Toll-like receptor 2 (TLR2). We investigated the role of TLR2 in pulmonary inflammation induced by hog confinement dust. Normal human bronchial epithelial cells (NHBE) were grown in culture and exposed to hog confinement dust extract. Hog confinement dust upregulated airway epithelial cell TLR2 mRNA in a concentration- and time-dependent manner using real-time PCR. There was a similar increase in TLR2 protein at 48 h as shown by Western blot. TLR2 was upregulated on the surface of airway epithelial cells as shown by flow cytometry. A similar upregulation of pulmonary TLR2 mRNA and protein was shown in a murine model of hog confinement dust exposure. Hog confinement dust is known to stimulate epithelial cells to produce IL-6. To determine whether TLR2 expression was being regulated by IL-6, the production of IL-6 was blocked using an IL-6-neutralizing antibody. This resulted in attenuation of the dust-induced upregulation of TLR2. To further demonstrate the importance of IL-6 in the regulation of TLR2, NHBE were directly stimulated with recombinant human IL-6. IL-6 alone was able to upregulate TLR2 in airway epithelial cells. Hog confinement dust upregulates TLR2 in the airway epithelium through an IL-6-dependent mechanism.

Exposure to hog barn dust alters airway epithelial ciliary beating.

Swine confinement workers are at increased risk of airway diseases, including mucus membrane irritation syndrome, chronic rhinosinusitis and chronic bronchitis. Dust extracts from swine confinement facilities stimulate the production of pro-inflammatory cytokines in bronchial epithelial cells, including interleukin (IL)-8. As IL-8 is capable of blocking beta-agonist-stimulated increases in cilia beating, which impacts on mucociliary clearance, it was hypothesised that hog barn-dust exposure might alter cilia responses to stimulation. To test this hypothesis, ciliated bovine bronchial epithelial cell cultures were exposed to hog barn-dust extract (HDE) and ciliary beat frequency (CBF) was assayed. An elevation in baseline CBF was observed. This effect appeared to be independent of endotoxin but dependent upon nitric oxide. HDE also stimulated nitric oxide production in bronchial epithelial cells; however, stimulation of cilia beating by a beta-agonist did not occur in cells pre-exposed to HDE. These data demonstrate that hog barn dust can alter normal stimulation of cilia, suggesting a mechanism for the abrogation of stimulated increases in mucociliary clearance in response to inhaled dust exposure.

Validated H5 Eurasian real-time reverse transcriptase-polymerase chain reaction and its application in H5N1 outbreaks in 2005-2006.

Real time reverse transcriptase (RRT)-polymerase chain reaction (PCR) for the detection of Eurasian H5 avian influenza virus (AIV) isolates was adapted from an existing protocol, optimized, and validated using a number of genetically diverse H5 isolates (n = 51). These included 34 "Asian lineage" H5N1 highly pathogenic avian influenza (HPAI) viruses (2004-2006), plus 12 other H5 isolates from poultry outbreaks and wild birds in the Eastern Hemisphere (1996-2005). All 51 were positive by H5 Eurasian RRT-PCR. Specificity was assessed by testing representative isolates from all other AL virus subtypes (n = 52), non-AI avian pathogens (n = 8), plus a negative population of clinical specimens derived from AI-uninfected wild birds and poultry (n = 604); all were negative by H5 Eurasian RRT-PCR. RNA was directly extracted from suspect HPAI H5N1 clinical specimens (Africa, Asia, and Europe; 2005-2006; n = 58) from dead poultry and wild birds, and 55 recorded as positive by H5 Eurasian RRT-PCR: Fifty-one of these 55 were in agreement with positive AIV isolation in embryonated chickens' eggs. H5 Eurasian RRT-PCR was invaluable in H5 outbreak diagnosis and management by virtue of its rapidity and high degree of sensitivity and specificity. This method provides a platform for automation that can be applied for large-scale intensive investigations, including surveillance.

Recent epidemiology and ecology of influenza A viruses in avian species in Europe and the Middle East.

There have been at least ten distinct outbreaks of LPAI or HPAI in poultry caused by H5 or H7 viruses in the last eight years in Europe and the Middle East. There appears to be an increased occurrence of such episodes consistent with global trends. As a result, surveillance systems have been enhanced to facilitate early detection of infection in poultry, together with active surveillance of wild bird populations. These complementary activities have resulted in the detection of a number of viruses in wild bird populations, including some with high genetic similarity to newly detected viruses in poultry, for example, H7N3 in Italy and H7N7 in the Netherlands. Furthermore, there is evidence for continued circulation of H5 and H7 viruses in wild Anseriformes, thereby presenting a real and current threat for the introduction of viruses to domestic poultry, especially those reared in outdoor production systems. Viruses of H9N2 subtype continue to circulate widely in the Middle East and are associated with significant disease problems in poultry. The epidemiology has the potential to be complicated further by introduction of novel viruses through illegal importation of captive birds, such as was detected with H5N1 in Belgium in 2004. Continual genetic exchange in the avian virus gene pool and independent evolution of all gene segments either within an individual host species or among wild bird hosts suggests that these viruses are not in evolutionary stasis in the natural reservoir.

Genetic subtyping of influenza A viruses using RT-PCR with a single set of primers based on conserved sequences within the HA2 coding region.

Influenza A viruses are subtyped conventionally according to the antigenic characteristics of the external glycoproteins, haemagglutinin (HA) and neuraminidase (NA). To date 15 HA and 9 NA subtypes have been described. There is a need to develop fast, accurate and reliable methods to identify influenza virus subtypes, which may be associated with disease outbreaks. An RT-PCR is described using a single primer pair based on a conserved region of the HA2 gene that can detect all 15 HA influenza A subtypes. The assay was validated initially using a panel of 12 known standard prototype strains of influenza virus representing 6 HA subtypes and subsequently in a blind study using a panel of 30 strains. Selected viruses represented all known HA subtypes derived from avian, swine and human hosts separated both geographically and with time Sequence analysis of RT-PCR product showed complete correlation with results obtained using conventional serological methods. It is concluded that this RT-PCR is a reliable, robust and reproducible tool for the rapid identification of a wide range of all the HA subtypes of influenza A viruses.

Hog barn dust extract augments lymphocyte adhesion to human airway epithelial cells.

The dust of hog confinement facilities induces airway inflammation. Mechanisms by which this dust modulates inflammation are not completely defined, although it is clear that exposure to dust can modulate both epithelial cell and inflammatory cell function. In this work, we demonstrate that airway epithelial cell (BEAS-2B) treatment with hog barn dust extract (HDE) results in augmentation of peripheral blood lymphocyte adhesion to epithelial cell cultures in vitro. The augmentation of lymphocyte adhesion to epithelial cells is dependent on the concentration of HDE and time of HDE exposure, with twofold increases observed by 3 h and maintained at 24 h. Similar results are seen with primary human bronchial epithelial cells in culture. Lymphocyte adhesion to epithelial cells is inhibited in a concentration-dependent fashion by the treatment of epithelial cells with antibody to intercellular adhesion molecule-1 (ICAM-1). In addition, HDE exposure of epithelial cells results in an approximate twofold increase in ICAM-1 expression as determined by flow cytometry analysis. Pretreatment of epithelial cells with a protein kinase C-alpha (PKC-alpha) inhibitor, Gö-6976, also inhibited subsequent lymphocyte adhesion to HDE-exposed epithelial cells. These data suggest that airway epithelial cell HDE exposure enhances subsequent lymphocyte adhesion to epithelial cells that is mediated in part by HDE modulation of ICAM-1 expression and PKC-alpha.

The respiratory inflammatory response to the swine confinement building environment: the adaptation to respiratory exposures in the chronically exposed worker.

Swine confinement facility workers often develop respiratory problems secondary to their work, including the asthma-like syndrome, exacerbation of underlying asthma, chronic bronchitis, and mucous membrane irritation syndrome. Organic dust toxic syndrome is seen in these workers as well. Swine confinement barns are characterized by the presence of multiple factors that can cause respiratory tract and systemic inflammation symptoms, including dust, endotoxin, and ammonia. Investigators have found evidence of inflammation characterized by increased numbers of neutrophils, macrophages, and to a lesser degree, lymphocytes in both naïve subjects and swine confinement building workers. Interestingly, this inflammation is most pronounced in subjects with no prior exposure to this environment. This finding suggests that adaptation or tolerance to endotoxin or other substances in this environment is induced by repeated exposures. Interventions have been devised to reduce the risk of symptomatic respiratory disease from working in a swine confinement facility. The efficacy of several of these interventions was tested using objective measures of respiratory tract inflammation. Recent finding suggests that such studies should be done in swine confinement workers if they appear promising using testing of naïve subjects exposed to this environment.

The relationship between agricultural environments and olfactory dysfunction.

OBJECTIVES: To examine the olfactory ability of farmers and identify exposures in agricultural environments associated with olfactory loss. STUDY DESIGN: Cross-sectional. METHODS: 405 individuals (214 males and 191 females) completed a questionnaire assessing agricultural exposures, health status, and olfactory history. Participants then completed a scratch-and-sniff 12-item odor identification test. Data analysis was conducted using the method of least squares to fit general linear models. Equality of outcome measures (the number of correctly identified odorants) between groups was evaluated using the Wilcoxon rank sum test. Differences were considered to be significant at the 0.05 level. RESULTS: Approximately 80% of participants reported active participation in farm work. Farmers correctly identified an average of 9.3 of 12 odorants, compared to 10.1 of 12 correctly identified by non-farmers, a difference that was not statistically significant (p = 0.2). Participants reporting sneezing after handling soybeans, wheat, or oats scored significantly lower than those without symptoms. There were suggestive associations between olfactory ability and exposure to anhydrous ammonia, history of wheezing and asthma, and a history of flu-like illness after farm work. CONCLUSIONS: Results indicate that, in general, farming is not associated with olfactory loss. However, we identified certain groups of farmers with inflammatory-type reactions who appeared to be susceptible to olfactory loss. The association between inflammatory reactions or conditions and olfactory loss is a novel finding.

Hog barn dust extract stimulates IL-8 and IL-6 release in human bronchial epithelial cells via PKC activation.

Hog barn workers have an increased incidence of respiratory tract symptoms and demonstrate an increase in lung inflammatory mediators, including interleukin (IL)-8 and IL-6. Utilizing direct kinase assays for protein kinase C (PKC) activation, we demonstrated that dust from hog confinement facilities, or hog dust extract (HDE), augments PKC activity of human airway epithelial cells in vitro. A 5% dilution of HDE typically stimulates an approximately twofold increase in human bronchial epithelial cell (HBEC) PKC activity compared with control medium-treated cells. This increase in PKC is observed with 15 min of HDE treatment, and kinase activity reaches peak activity by 1-2 h of HDE treatment before returning to baseline PKC levels between 6 and 24 h. The classic PKC inhibitor, calphostin C, blocks HDE-stimulated PKC activity and associated IL-8 and IL-6 release. Desensitization to HDE stimulation of PKC activation does not appear to occur because subsequent exposures to HDE after an initial exposure result in further augmentation of PKC. Detoxification of HDE with polymyxin B to remove endotoxin did not change PKC activation or IL-8 release, suggesting that endotoxin is not solely responsible for HDE augmentation of PKC. These data support the hypothesis that HDE exposure augments HBEC IL-8 and IL-6 release via a PKC-dependent pathway.