Nitric oxide-donating properties of mesoionic 3-aryl substituted oxatriazole-5-imine derivatives.

1. The nitric oxide (NO)-releasing properties of two new mesoionic 3-aryl substituted oxatriazole-5-imine derivatives (GEA 3162 and GEA 3175) were characterized and compared with the known NO-donors 3-morpholino-sydnonimine (SIN-1) and S-nitroso-N-acetylpenicillamine (SNAP). 2. GEA 3162, GEA 3175, SIN-1 and SNAP inhibited adenosine 5'-diphosphate-induced platelet aggregation (IC50 values 0.18, 0.39, 3.73 and 2.12 microM, respectively). All four compounds induced a dose-dependent and more than 4 fold increase in cyclic GMP in platelets. The increase in cyclic GMP concentration was potentiated more than 1.5 fold by a phosphodiesterase inhibitor, zaprinast (10 microM) and inhibited 38-97% by oxyhaemoglobin (10-45 microM). 3. All of the four compounds studied converted oxyhaemoglobin to methaemoglobin and formed a paramagnetic NO-haemoglobin complex. All but GEA 3175 formed nitrite and nitrate in phosphate buffer. During a 40 min incubation, GEA 3162, SIN-1 and SNAP (100 microM) produced 50-70 microM NO2- + NO3- as determined by high performance liquid chromatography. The release of NO and NO2 by GEA 3175 was increased 140 fold in the presence of human plasma (0.14 and 19.7 ppb in the absence and presence of 1% human plasma, respectively) as analyzed by ozone chemiluminescence. 4. The results suggest that the mesoionic 3-aryl substituted oxatriazole-5-imine derivatives GEA 3162 and GEA 3175 as well as SIN-1 and SNAP release nitric oxide.     

Endothelium-dependent and -independent effects of exogenous ATP, adenosine, GTP and guanosine on vascular tone and cyclic nucleotide accumulation of rat mesenteric artery.

1. The effects of exogenous guanosine 5'-triphosphate (GTP) and guanosine on vascular tone and cyclic nucleotide accumulation of noradrenaline-precontracted endothelium-intact and endothelium-denuded rat mesenteric artery rings were compared with the effects of the known purinoceptor agonists adenosine 5'-triphosphate (ATP) and adenosine. 2. GTP (10 microM-1 mM) dose-dependently relaxed endothelium-intact mesenteric artery rings by producing a rapid initial response followed by sustained relaxation resembling the relaxant response to acetylcholine. GTP also slightly relaxed endothelium-denuded artery rings. The acetylcholine- and GTP-induced relaxations of endothelium-intact rings were attenuated by NG-nitro L-arginine methyl ester (L-NAME, 330 microM) which attenuation was reversed with L-arginine (1 mM). 3. Guanosine (10 microM-1 mM) relaxed both endothelium-intact and -denuded artery rings in a dose-dependent manner. The relaxations were more pronounced in endothelium-intact preparations and were only slightly attenuated by L-NAME (330 microM). 4. ATP (1 microM-1 mM) and adenosine (10 microM-1 mM) dose-dependently relaxed endothelium-intact and -denuded artery rings. The responses were more pronounced in endothelium-intact vascular preparations. 5. GTP (100 microM) and guanosine (100 microM) increased guanosine 3':5'-cyclic monophosphate (cyclic GMP) accumulation in both endothelium-intact and -denuded artery rings corresponding to the relaxations observed. The concentrations of adenosine 3':5'-cyclic monophosphate (cyclic AMP) were not affected. 6. ATP (100 microM) increased cyclic GMP concentration of endothelium-intact artery rings. The concentrations of cyclic AMP were not affected by ATP (100 microM) and adenosine (100 microM) in endothelium-intact and -denuded vascular preparations.(ABSTRACT TRUNCATED AT 250 WORDS)     

Real-time PCR for rapid diagnosis of entero- and rhinovirus infections using LightCycler.

BACKGROUND: PCR techniques have proved to be more sensitive than traditional cell culture in the diagnosis of enterovirus and rhinovirus infections and are widely used in clinical virus laboratories. However, PCR assays are relatively time-consuming and labor intensive, particularly if separate hybridization steps are used to confirm the specificity of positive findings. OBJECTIVES: The aim of the present study was to develop fast and sensitive real-time PCR assay, which would allow simultaneous detection of entero- and rhinoviruses and their quantification in clinical and experimental samples. STUDY DESIGN: Two real-time RT-PCR protocols were developed using LightCycler (LC) technology; SYBRGreen and hybridization probe assays. The sensitivity of these assays to detect entero- and rhinoviruses was compared with that of a traditional reference RT-PCR-hybridization assay and cell culture. All PCR protocols used the same primers amplifying the 5'-non coding region (NCR) of entero- and rhinoviruses. The LC probe assay and the reference RT-PCR used almost identical detection probes, which bind to enterovirus specific amplicons. RESULTS AND CONCLUSIONS: Both real-time PCR assays were equally sensitive as the reference RT-PCR-assay and all were more sensitive than cell culture. Both real-time assays quantified reliably the amount of the virus and took much shorter time than the reference RT-PCR. As the real-time SYBRGreen assay detects both entero- and rhinoviruses it can be used for primary screening of samples, which can be positive for either of these viruses. The real-time probe-assay can confirm the presence of enterovirus in SYBRGreen positive samples or it can be used for selective screening of enteroviruses e.g. from CSF samples.     

Coxsackievirus B3-induced acute pancreatitis: analysis of histopathological and viral parameters in a mouse model.

Coxsackievirus B3 infection in mice was studied histopathologically, by virus isolation and by nucleic acid hybridization after intraperitoneal inoculation of the virus. Extensive viraemia was detected for 1-3 days post-infection. All mice developed necrotizing acute pancreatitis and focal myocarditis. Pancreatitis eventually lead to complete atrophy of the exocrine pancreas. However, the islets of Langerhans and pancreatic ducts remained morphologically intact. Virus could be demonstrated in pancreatic tissue for 1-5 days post-infection by in-situ and spot hybridization as well as by virus isolation. Virus was not detectable on days 7-22 post-infection suggesting an autodigestive aetiology in further destruction of the exocrine pancreas. The mouse model described here permits detailed analysis of viral and host factors in the pathogenesis of enterovirus infections. Since coxsackie B viruses have been proposed to be aetiological agents in human acute pancreatitis, the application of in-situ hybridization allows analysis of enteroviruses directly from pancreatic tissue of clinical routine specimens.     

Effect of surgical stress on the erythrocyte insulin receptor

The aim of this study was to investigate whether surgical trauma causes changes in insulin receptors which may have significance on the causation of post-traumatic insulin resistance. Twenty-four patients scheduled for lumbar intervertebral disc operations or thoracotomy were investigated. In patients who did not receive glucose during operation blood glucose and plasma insulin concentrations did not change but lipolysis was induced as indicated by the increase of serum free fatty acids concentration. Glucose infusion (5% w/v) caused a hyperglycaemic and hyperinsulaenemic response without lipolysis. In patients not receiving a glucose load the number of insulin receptors on erythrocyte measured 4 h postoperatively increased from the preoperative values and the affinity of the receptors to insulin in physiological concentration range increased. In patients with glucose load the number of receptors decreased and receptor affinity to insulin at physiological concentration decreased. The results suggest that in patients receiving a glucose load the receptor changes indicate the perioperative development of insulin resistance at receptor level.     

Transmission of Streptococcus equi Subspecies zooepidemicus Infection from Horses to Humans

Streptococcus equi subspecies zooepidemicus (S. zooepidemicus) is a zoonotic pathogen for persons in contact with horses. In horses, S. zooepidemicus is an opportunistic pathogen, but human infections associated with S. zooepidemicus are often severe. Within 6 months in 2011, 3 unrelated cases of severe, disseminated S. zooepidemicus infection occurred in men working with horses in eastern Finland. To clarify the pathogen’s epidemiology, we describe the clinical features of the infection in 3 patients and compare the S. zooepidemicus isolates from the human cases with S. zooepidemicus isolates from horses. The isolates were analyzed by using pulsed-field gel electrophoresis, multilocus sequence typing, and sequencing of the szP gene. Molecular typing methods showed that human and equine isolates were identical or closely related. These results emphasize that S. zooepidemicus transmitted from horses can lead to severe infections in humans. As leisure and professional equine sports continue to grow, this infection should be recognized as an emerging zoonosis.     

Rhinovirus species and clinical characteristics in the first wheezing episode in children

The clinical data on the first wheezing episodes induced by different rhinovirus (RV) species are still limited. We aimed to investigate the prevalence of RV genotypes, sensitization status, and clinical characteristics of patients having a respiratory infection caused by either different RV species or other respiratory viruses. The study enrolled 111 patients (aged 3–23 months, 79% hospitalized, 76% with RV infection) with the first wheezing episode. RV‐specific sequences were identified by partial sequencing of VP4/VP2 and 5′ non‐coding regions with 80% success rate. The investigated clinical and laboratory variables included atopic characteristics and illness severity, parental atopic illnesses, and parental smoking. Of the study children, 56% percent had > 1 atopic characteristic (atopy, eczema and/or blood eosinophil count > 0.4 × 10⁹/L) and 23% were sensitised to allergens. RV‐C was detected in 58% of RV positive samples, followed by RV‐A (20%) and RV‐B (1.2%). Children with RV‐A and RV‐C induced wheezing were older (P = 0.014) and had more atopic characteristics (P = 0.001) than those with non‐RV. RV‐A and RV‐C illnesses had shorter duration of preadmission symptoms and required more bronchodilator use at the ward than non‐RV illnesses (both P < 0.05, respectively). RV‐C is the most common cause of severe early wheezing. Atopic and illness severity features are associated with children having RV‐A or RV‐C induced first wheezing episode rather than with children having a non‐RV induced wheezing. J. Med. Virol. 88:2059–2068, 2016. © 2016 Wiley Periodicals, Inc.

     

Preschool teachers' views on competence in the context of home and preschool collaboration

The purpose of this article is to analyse and discuss preschool teachers' views regarding competence within their profession in the context of home and preschool collaboration. The question addressed is as follows: In what situations do preschool teachers perceive that their competence becomes visible for parents? The results, based on interviews with 30 preschool teachers, show that preschool teachers work consciously to draw attention to specific competencies related to children's learning and development and the preschool curriculum. The ability to establish dialogue with parents and gain their trust is seen as particularly important for establishing and maintaining collaboration between preschool and the home. Furthermore, the participants recognise that parents seek their competence in daily matters concerning the child's well-being. The competencies that preschool teachers emphasise and those they believe parents ask for do not, therefore, always coincide. The results of this study can contribute to a better understanding of the prerequisites for preschool–home collaboration.