Neuroanatomical and morphometric study of S100ß positive astrocytes in the entorhinal cortex during ageing in the 3xTg-Alzehimer's disease mouse model.

Astrocytes contribute to the progression of neurodegenerative diseases, including Alzheimer's disease (AD). Here, we report the neuroanatomical and morphometric analysis of astrocytes in the entorhinal cortex (EC) of the aged wild type (WT) and triple transgenic (3xTg-AD) mouse model of AD. Using 3D confocal microscopy, we determined the surface area and volume of positive astrocytic profiles in male mice (WT and 3xTg-AD) from 1 to 18 months of age. We showed that S100ß-positive astrocytes were equally distributed throughout the entire EC in both animal types and showed no changes in Nv (number of cells/mm3) nor in their distribution at the different ages studied. These positive astrocytes, demonstrated an age-dependent gradual increase in their surface area and in their volume starting at 3 months of age, in both WT and 3xTg-AD mice. This last group demonstrated a large increase in both surface area and volume at 18 months of age when the burden of pathological hallmarks of AD is present (69.74% to 76.73% in the surface area and the volume, for WT and 3xTg-AD mice respectively). We observed that these changes were due to the enlargement of the cell processes and to less extend the somata. In fact, the volume of the cell body was increased by 35.82% in 18-month-old 3xTg-AD compared to WT. On the other hand, the increase on the astrocytic processes were detected as soon as 9 months of age where we found an increase of surface area and volume (36.56% and 43.73%, respectively) sustained till 18 month of age (93.6% and 113.78%, respectively) when compared age-matched non-Tg mice. Moreover, we demonstrated that these hypertrophic S100ß-positive astrocytes were mainly associated with Aß plaques. Our results show a severe atrophy in GFAP cytoskeleton in all cognitive areas; whilst within the EC astrocytes independent to this atrophy show no changes in GS and S100ß; which can play a key role in the memory impairment.

Single nucleotide polymorphisms of the inflamatory cytokine genes: interleukin-1B, tumor necrosis factors-A and tumor necrosis factor-B in adult patients with immune thrombocytopenia.

Immune thrombocytopenia (ITP) is an autoimmune disease characterized by thrombocytopenia due to platelet autoantibodies, causing an accelerated clearance of opsonized platelets by phagocytes. The etiology of ITP remains unclear, both genetic and environmental factors may have a role in the disease development. The aim of our study was to investigate a possible association of three single nucleotide polymorphisms (SNP) in the genes for interleukin beta (IL1B-511C/T), tumor necrosis factor beta (TNF+252G/A) and tumor necrosis factor alpha (TNFA-308G/A) with ITP. We have analyzed 125 adult patients with ITP and 120 healthy matched controls. Genotyping was performed by using PCR- RFLP methods. Our results demonstrated significantly different genotype distributions and allele frequencies for TNFB+252G/A in patients with ITP, p = 0.005 and p = 0.009 with Yates correction. We did not find any significant differences in the genotype distribution or allele frequencies for the other two genes. We have found significantly different genotype distribution and allele frequencies for TNFA-308G/A between patients with unresponsive and responsive ITP patients, p = 0.016 and p = 0.009. There were no significant differences in genotype distribution and allele frequencies for ILB-511C/T and TNFB+252G/A polymorphisms between those two groups of patients. We did not find any significant differences in genotype distribution and allele frequencies for all three polymorphisms between splenectomized and unsplenectomized ITP patients. The obtained data indicate that the A allele of TNFB+252G/A is more frequent in these patients than in the controls and that this polymorphism may play a significant role in disease susceptibility. The A allele of TNFA-308G/A was more frequent in patients with unresponsive ITP, indicating that this gene polymorphisms may contribute to therapy resistance.

Immune thrombocytopenic purpura in adults in the last 10 years: single-centre experience.

BACKGROUND: Immune thrombocytopenic purpura (ITP) is a benign disease with low morbidity and mortality and frequent remissions that occur spontaneously or in response to first-line treatment with steroids or splenectomy. AIM: The purpose of this study is to describe the clinical outcomes of 170 patients with ITP diagnosed and/or treated in our hospital between 2000 and 2010. METHODS AND RESULTS: The median age at diagnosis was 47 years. Forty three (25%) were asymptomatic, 65% had minor skin or mucosal bleeding and 10% had significant bleeding from the gastrointestinal or genitourinary system. The median platelet count at diagnosis was 13x10(9)/L (range: 0-98x10(9)/L). Median follow-up of all patients was 13 months. Ninety-five patients had a follow-up longer than 12 months, with median 44 months (range 14-384). Corticosteroids were the initial treatment for 161/170 (95%) patients, 38 (22%) were splenectomized, 25 (14.7%) were treated with intravenous gamma globulins, while 9 did not received any specific treatment. A complete response to initial treatment (prednisone±splenectomy) was achieved in 55/161 (34.2%), a partial response in 90 (55.9%) and no response in 16 (9.9%) patients. In the group of patients with follow-up longer than 1 year; 28 (29%) patients had refractory or unresponsive ITP with a median follow-up of 66 months. All patients with refractory ITP were treated with steroids, 11 were splenctomized, significantly more patients with refractory ITP 12 (43%) were treated with IVIG compared with other ITP patients (16%), p=0.005. The median age of 38 splenectomized patients was 28 years and it is significantly different from the other patients (p<0.001). There were no significant differences in other characteristics between splenctomized or refractory ITP and other patients at diagnosis. CONCLUSION: Our results were similar to results already reported in other similar studies.

Comparison of methods for detection and enumeration of airborne microorganisms collected by liquid impingement.

Bacterial agents and cell components can be spread as bioaerosols, producing infections and asthmatic problems. This study compares four methods for the detection and enumeration of aerosolized bacteria collected in an AGI-30 impinger. Changes in the total and viable concentrations of Pseudomonas fluorescens in the collection fluid with respect to time of impingement were determined. Two direct microscopic methods (acridine orange and BacLight) and aerodynamic aerosol-size spectrometry (Aerosizer) were employed to measure the total bacterial cell concentrations in the impinger collection fluid and the air, respectively. These data were compared with plate counts on selective (MacConkey agar) and nonselective (Trypticase soy agar) media, and the percentages of culturable cells in the collection fluid and the bacterial injury response to the impingement process were determined'. The bacterial collection rate was found to be relatively unchanged during 60 min of impingement. The aerosol measurements indicated an increased amount of cell fragments upstream of the impinger due to continuous bacterial nebulization. Some of the bacterial clusters, present in the air upstream of the impinger, deagglomerated during impingement, thus increasing the total bacterial count by both direct microscopic methods. The BacLight staining technique was also used to determine the changes in viable bacterial concentration during the impingement process. The percentage of viable bacteria, determined as a ratio of BacLight live to total counts was only 20% after 60 min of sampling. High counts on Trypticase soy agar indicated that most of the injured cells could recover. On the other hand, the counts from the MacConkey agar were very low, indicating that most of the cells were structurally damaged in the impinger. The comparison of data on the percentage of injured bacteria obtained by the traditional plate count with the data on percentage of nonviable bacteria obtained by the BacLight method showed good agreement.

Effect of impact stress on microbial recovery on an agar surface.

Microbial stress due to the impaction of microorganisms onto an agar collection surface was studied experimentally. The relative recovery rates of aerosolized Pseudomonas fluorescens and Micrococcus luteus were determined as a function of the impaction velocity by using a moving agar slide impactor operating over a flow rate range from 3.8 to 40 liters/min yielding impaction velocities from 24 to 250 m/s. As a reference, the sixth stage of the Andersen Six-Stage Viable Particle Sizing Sampler was used at its operating flow rate of 28.3 liters/min (24 m/s). At a collection efficiency of close to 100% for the agar slide impactor, an increase in sampling flow rate and, therefore, in impaction velocity produced a significant decline in the percentage of microorganisms recovered. Conversely, when the collection efficiency was less than 100%, greater recovery and lower injury rates occurred. The highest relative rate of recovery (approximately 51% for P. fluorescens and approximately 62% for M. luteus) was obtained on the complete (Trypticase soy agar) medium at 40 and 24 m/s (6.4 and 3.8 liters/min), respectively. M. luteus demonstrated less damage than P. fluorescens, suggesting the hardy nature of the gram-positive strain versus that of the gram-negative microorganism. Comparison of results from the agar slide and Andersen impactors at the same sampling velocity showed that recovery and injury due to collection depends not only on the magnitude of the impaction velocity but also on the degree to which the microorganisms may be embedded in the collection medium.(ABSTRACT TRUNCATED AT 250 WORDS)

Survival and injury of Escherichia coli, Campylobacter jejuni, and Yersinia enterocolitica in stream water.

Experiments were done to describe the survival and injury of three strains each of enteropathogenic Escherichia coli, Yersinia enterocolitica, and Campylobacter jejuni in agricultural surface water. Bacterial suspensions within membrane diffusion chambers were immersed in two large vessels of stream water that were held at 6 and 16 degrees C and changed daily. The results of daily plate counts, using selective and nonselective media, revealed some variation among strains and genera. Injury increased rapidly in all of the bacteria examined during an initial 4-day period of population stability. Bacterial persistence was generally prolonged at 6 degrees C, while the occurrence of injury was directly related to temperature. However, both survival and injury in C. jejuni were less dependent on temperature, while Y. enterocolitica displayed the greatest survival at both 6 and 16 degrees C. These results suggest that surface water in the temperate zone might serve as a persistent vehicle for the transmission of these enteropathogenic bacteria between animals and humans.

Survival ofEscherichia coli andYersinia enterocolitica in stream water: Comparison of field and laboratory exposure.

Experiments were done to compare the influence of three aquatic exposure methods on the behavior of pathogenic and nonpathogenic enteric bacteria (Yersinia enterocolitica andEscherichia coli). Bacterial suspensions were exposed to stream water in membrane diffusion chambers in situ as well as in the laboratory using a large vessel of stream water and in enclosed bottles. The persistence of culturability of the bacterial suspensions was dependent upon the method of aquatic exposure. This difference was most apparent during the initial six days of each experiment. A steady decline in colony forming units was seen after a short stationary period in chambers in situ, while there was an abrupt increase in bacteria within chambers exposed in the laboratory. A rapid initial decrease was observed in the experimental variation using bottles, accompanied by higher levels of injury inE. coli and reduced expression of plasmid-borne virulence phenotypes inY. enterocolitica. However, there were no changes in the plasmid profiles of either organism throughout the 21-day duration of the experiments. In addition, the survival and injury of pathogenic and nonpathogenic strains of both test bacteria was very similar with aquatic exposure. These results suggest that the response of enteric bacteria in aquatic environments is influenced by experimental design as well as other factors and that the comparison of survival data should only be attempted when similar methods are used.

[Virulence of the microbial preparation Bactorodencide for various animal species]. / Virulentnost na mikrobialniia preparat "Baktorodentsid" za razlichni vidove zhivotni.

The virulence of the biological preparation for plant protection Bactorodencite is studied in 6 species of wild and domestic animals and game. Its high specificity concerning rodents is established at the highest rate in Ratus Norvegicus and inbred mice - C57 Black. Indocile to S. enteritidis var. issatschenko (active start of the Bactorodencite) are the grey pigeons, hens, ducks, pheasants, lambs and pigs. The time for clearing the organism of the indocile animals depends on the quantity (dose) absorbed bacteria, the specy of animals, and is not longer than 18-20 days.