First-order structural transition in the multiferroic perovskite-like formate [(CH3)2NH2][Mn(HCOO)3]

In this work we explore the overall structural behaviour of the [(CH3)2NH2][Mn(HCOO)3] multiferroic compound across the temperature range where its ferroelectric transition takes place by means of calorimetry, thermal expansion measurements and variable temperature powder and single crystal X-ray diffraction. The results clearly proof the presence of structural phase transition at Tt ~187 K (temperature at which the dielectric transition occurs) that involves a symmetry change from R-3c to Cc, twinning of the crystals, a discontinuous variation of the unit cell parameters and unit cell volume, and a sharp first-order-like anomaly in the thermal expansion. In addition, the calorimetric results show a 3-fold order-disorder transition. The calculated pressure dependence of the transition temperature is rather large (dTt/dP = 4.6 $\pm$ 0.1 K/kbar), so that it should be feasible to shift it to room temperature using adequate thermodynamic conditions, for instance by application of external pressure

alpha-Galactosylceramide protects swine against influenza infection when administered as a vaccine adjuvant

Citation: Artiaga, B. L., Yang, G., Hackmann, T. J., Liu, Q. F., Richt, J. A., Salek-Ardakani, S., . . . Driver, J. P. (2016). alpha-Galactosylceramide protects swine against influenza infection when administered as a vaccine adjuvant. Scientific Reports, 6, 13. doi:10.1038/srep23593Natural killer T (NKT)-cells activated with the glycolipid ligand a-galactosylceramide (alpha-GalCer) stimulate a wide array of immune responses with many promising immunotherapeutic applications, including the enhancement of vaccines against infectious diseases and cancer. In the current study, we evaluated whether alpha-GalCer generates protective immunity against a swine influenza (SI) virus infection when applied as an intramuscular vaccine adjuvant. Immunization of newly weaned piglets with UV-killed pandemic H1N1 A/California/04/2009 (kCA04) SI virus and alpha-GalCer induced high titers of anti-hemagglutinin antibodies and generated virus-specific T cells that localized in intrapulmonary airways and in alveolar walls. Vaccination with alpha-GalCer resulted in a systemic increase in NKT-cell concentrations, including in the respiratory tract, which was associated with complete inhibition of viral replication in the upper and lower respiratory tract and much reduced viral shedding. These results indicate that NKT-cell agonists could be used to improve swine vaccine formulations in order to reduce the clinical signs of SI infection and limit the spread of influenza viruses amongst commercial pigs

Determinants of gastric CDX2 expression : a study in Mozambique

As CDX2 expression precedes the occurrence of gastric preneoplastic lesions in the intestinal differentiation pathway, study of these steps of gastric carcinogenesis may contribute toward understanding the early effects of gastric cancer determinants. Our aim was to quantify the association between Helicobacter pylori infection and other environmental factors and the gastric expression of CDX2. Dyspeptic patients undergoing an upper digestive endoscopy (Gastroenterology Department, Maputo Central Hospital) were consecutively invited to participate in this study and classified as having normal stomach/chronic nonatrophic gastritis (NS/CNAG), chronic atrophic gastritis (CAG), or intestinal metaplasia (IM). For all patients with CAG or IM and a subsample of NS/CNAG patients (sex-matched and age-matched, 1\u2009:\u20092), H. pylori infection and CDX2 gene expression were assessed by histology and PCR and by immunohistochemistry, respectively. Age-adjusted, sex-adjusted, education-adjusted, and H. pylori infection-adjusted odds ratios (OR) and 95% confidence intervals (95% CI) were computed. CDX2 expression was observed in 56 NS/CNAG (49.1%), 39 CAG (86.7%), and all IM patients (n=12). It was more frequent among the H. pylori-infected patients (OR=2.26, 95% CI: 1.00-5.15). Infection with high-virulence strains was associated with CDX2 expression in patients with CAG (cagA, OR=3.20, 95% CI: 1.35-7.52) and IM (vacA m1, OR=5.86, 95% CI: 1.08-31.62). Patients with a lower frequency of vegetable consumption had a higher risk of marked CDX2 expression (OR=3.64, 95% CI: 1.02-12.95). The virulence of the infecting strains and vegetable consumption were associated with CDX2 expression and may play a role in the progression to more advanced lesions

First-order structural transition in the multiferroic perovskite-like formate [(CH3)(2)NH2][Mn(HCOO)(3)]

In this work we explore the overall structural behaviour of the [(CH 3)2NH2][Mn(HCOO)3] multiferroic compound across the temperature range where its ferroelectric transition takes place by means of calorimetry, thermal expansion measurements and variable temperature powder and single crystal X-ray diffraction. The results clearly prove the presence of a structural phase transition at Tt ~ 187 K (the temperature at which the dielectric transition occurs) that involves a symmetry change from R3c to Cc, twinning of the crystals, a discontinuous variation of the unit cell parameters and unit cell volume, and a sharp first-order-like anomaly in the thermal expansion. In addition, the calorimetric results show a 3-fold order-disorder transition. The calculated pressure dependence of the transition temperature is rather large (dTt/dP = 4.6 ± 0.1 K kbar-1) in that it should be feasible to shift it to room temperature under adequate thermodynamic conditions, for instance by application of an external pressure. © 2014 the Partner Organisations

Sars-Cov-2 Infection, Disease And Transmission In Domestic Cats

Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) is the cause of Coronavirus Disease 2019 (COVID-19) and responsible for the current pandemic. Recent SARS-CoV-2 susceptibility studies in cats show that the virus can replicate in these companion animals and transmit to other cats. Here, we present an in-depth study of SARS-CoV-2 infection, disease and transmission in domestic cats. Cats were challenged with SARS-CoV-2 via intranasal and oral routes. One day post challenge (DPC), two sentinel cats were introduced. Animals were monitored for clinical signs, clinicopathological abnormalities and viral shedding. Postmortem examinations were performed at 4, 7 and 21 DPC. Viral RNA was not detected in blood but transiently in nasal, oropharyngeal and rectal swabs and bronchoalveolar lavage fluid as well as various tissues. Tracheobronchoadenitis of submucosal glands with the presence of viral RNA and antigen was observed in airways of the infected cats. Serology showed that both, principals and sentinels, developed antibodies to SARS-CoV-2. All animals were clinically asymptomatic during the course of the study and capable of transmitting SARS-CoV-2 to sentinels. The results of this study are critical for understanding the clinical course of SARS-CoV-2 in a naturally susceptible host species, and for risk assessment

Experimental Re-Infected Cats Do Not Transmit Sars-Cov-2

SARS-CoV-2 is the causative agent of COVID-19 and responsible for the current global pandemic. We and others have previously demonstrated that cats are susceptible to SARS-CoV-2 infection and can efficiently transmit the virus to naive cats. Here, we address whether cats previously exposed to SARS-CoV-2 can be re-infected with SARS-CoV-2. In two independent studies, SARS-CoV-2-infected cats were re-challenged with SARS-CoV-2 at 21 days post primary challenge (DPC) and necropsies performed at 4, 7 and 14 days post-secondary challenge (DP2C). Sentinels were co-mingled with the re-challenged cats at 1 DP2C. Clinical signs were recorded, and nasal, oropharyngeal, and rectal swabs, blood, and serum were collected and tissues examined for histologic lesions. Viral RNA was transiently shed via the nasal, oropharyngeal and rectal cavities of the re-challenged cats. Viral RNA was detected in various tissues of re-challenged cats euthanized at 4 DP2C, mainly in the upper respiratory tract and lymphoid tissues, but less frequently and at lower levels in the lower respiratory tract when compared to primary SARS-CoV-2 challenged cats at 4 DPC. Viral RNA and antigen detected in the respiratory tract of the primary SARS-CoV-2 infected cats at early DPCs were absent in the re-challenged cats. Naive sentinels co-housed with the re-challenged cats did not shed virus or seroconvert. Together, our results indicate that cats previously infected with SARS-CoV-2 can be experimentally re-infected with SARS-CoV-2; however, the levels of virus shed was insufficient for transmission to co-housed naive sentinels. We conclude that SARS-CoV-2 infection in cats induces immune responses that provide partial, non-sterilizing immune protection against re-infection