Increased radial glia quiescence,decreased reactivation upon injury and unaltered neuroblast behavior underlie decreased neurogenesis in the aging zebrafish telencephalon

The zebrafish has recently become a source of new data on the mechanisms of neural stem cell (NSC) maintenance and ongoing neurogenesis in adult brains. In this vertebrate, neurogenesis occurs at high levels in all ventricular regions of the brain, and brain injuries recover successfully, owing to the recruitment of radial glia, which function as NSCs. This new vertebrate model of adult neurogenesis is thus advancing our knowledge of the molecular cues in use for the activation of NSCs and fate of their progeny. Because the regenerative potential of somatic stem cells generally weakens with increasing age, it is important to assess the extent to which zebrafish NSC potential decreases or remains unaltered with age. We found that neurogenesis in the ventricular zone, in the olfactory bulb, and in a newly identified parenchymal zone of the telencephalon indeed declines as the fish ages and that oligodendrogenesis also declines. In the ventricular zone, the radial glial cell population remains largely unaltered morphologically but enters less frequently into the cell cycle and hence produces fewer neuroblasts. The neuroblasts themselves do not change their behavior with age and produce the same number of postmitotic neurons. Thus, decreased neurogenesis in the physiologically aging zebrafish brain is correlated with an increasing quiescence of radial glia. After injuries, radial glia in aged brains are reactivated, and the percentage of cell cycle entry is increased in the radial glia population. However, this reaction is far less pronounced than in younger animals, pointing to irreversible changes in aging zebrafish radial glia. J. Comp. Neurol. 521: 3099–3115, 2013. © 2013 Wiley Periodicals, Inc.     

Mortality of Roma population in Serbia, 2002-2005

Aim

To describe and compare mortality and population changes in the Roma and non-Roma population in Serbia in 2002 and 2005.

Methods

The number of cases of death were obtained from the 2002 and 2005 Mortality Database and population data from the Population Census 2002. Standardized sex specific rates of non-traumatic and traumatic mortality in 2002 and 2005 were calculated in relation to the European standard population. We presented population pyramid and aging index for both populations in 2002 and compared sex specific standardized traumatic and non-traumatic mortality rates and the average age of death for 2002 and 2005. The causes of death were coded according to the 10th revision of the International Classification of Diseases (ICD-10) groups, and the proportional mortalities in the year 2002 and 2005 were compared between the Roma and non-Roma population using χ² test.

Results

Standardized mortality rates were higher in the Roma than in the general population. Non-traumatic mortality rate in Roma men in 2002 was 18.2 per 1000 and in slightly decreased to 18.0 per 1000 in 2005; it was significantly higher than in non-Roma men in both years (11.9 per 1000 in 2002 and 12.5 per 1000 in 2005; P<0.001). Standardized non-traumatic mortality rate in Roma women decreased significantly from 16.78 per 1000 in 2002 to 14.89 per 1000 in 2005 (P=0.014), but it was still significantly higher than in non-Roma women (8.46 per 1000 in 2002 and 8.84 per 1000 in 2005; P<0.001). Morbidity structure indicated that the most common causes of death in the Roma population were cardiovascular diseases, neoplasms, and respiratory system diseases. In relation to the general population respiratory system diseases were denoted as main causes of deaths in significantly higher percent (6% vs 3% in 2002 and 7% vs 4% in 2005; P<0.001) and cardiovascular diseases in significantly lower percent (44%:55% in 2002 and 46%:57%; P<0.001).

Conclusions

Our data show that mortality rates in the Roma population are significantly higher than in the general population, and morbidity structure of the most common causes of death significantly different from that of general population.According to the most recent population census in the Serbia from 2002, 108 193 or 1.44% residents declared themselves as Romani. The Roma population is among the most imperiled and potentially most vulnerable groups. Living Standards Measurement Survey (LSMS) conducted in Serbia in 2002-2003 indicated significant differences in living conditions between the Roma and non-Roma population (1). The prevalence of poverty, defined as an average total consumption below the poverty line of 57 euros per month/consumption unit, in the Roma population was as high as 64.4%, which is 6.1 times more frequent than in the general population (10.5%) (1). Extremely low level of education and very high level of unemployment characterize the social status of the Romani people. Almost two thirds (62%) of the Roma older than 15 years did not finish primary school, as opposed to 19% of the general population (1). The unemployment rate is also high, reaching 45%, while in the rest of the Serbian population it amounts to 9% (1). Such findings are not unexpected since these characteristics are highly associated with poverty (1).Although the range of vaccination coverage in Serbian general population is 98%-100%, many Roma children are not included in vaccination programs (2). Twenty nine percent of Roma children aged 18-29 months do not even have vaccination cards. Data regarding the education of Roma children are also discouraging: 62% of them attended pre-school programs one year prior to the first grade, as opposed to 89% children in the general population. Also, the vast majority (98%) of children of primary school age in general population attends school, while the attendance rate among Roma children is significantly lower (74%). The difference between the proportions of Roma children and children in general population who attend secondary schools is even more drastic (only 10% vs 85%).During the last decade, several studies dealing with diverse problems of the Roma population have been conducted in South-Eastern Europe (3-10). Compared with the general populations in Eastern and Central Europe, life expectancy of the Roma population is 10-year shorter because of poor living conditions and poverty (11). A study conducted in the Czechoslovakia in 1989 compared census data and pointed out that life expectancy of the Roma men and women were 12.1 and 14.4 years, respectively, shorter than in the general population (12).The aim of this study was to describe and compare mortality and population changes in the Roma and non-Roma population in Serbia in 2002 and 2005. We present population pyramid and aging index for both populations for the year 2002 and compared sex specific standardized traumatic and non-traumatic mortality rates and the average age of death for 2002 and 2005.     

CYP1A induction potential and the concentration of priority pollutants in marine sediment samples -In vitro evaluation using the PLHC-1 fish hepatoma cell line

The use of in vitro biotests in combination with chemical determination of priority pollutants is considered a promising approach in environmental risk assessment. The main goal of this study was to evaluate the relationship between the CYP1A induction potential and the concentration of priority pollutants (PAHs, PCBs and heavy metals) in contaminated marine sediments. Six sediment samples characterized by different types of pollution were collected from the Bay of Kvarner, Croatia. CYP1A induction potency was determined in vitro by the measurement of ethoxyresorufin-O-deethylase (EROD) activity in PLHC-1 fish hepatoma cells. The results were compared to the potency of the model CYP1A inducer 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and expressed in 2,3,7,8-TCDD equivalents. All of the tested sediment samples were able to induce CYP1A activity in a dose-dependent manner. On a general scale, there was a good correlation between CYP1A induction and the concentration of priority pollutants in the tested samples. However, some samples, which had relatively low levels of priority pollutants, exhibited a strong CYP1A induction response. Therefore, apart from the confirmed usability and sensitivity of the EROD determination in the PLHC-1 cells as a suitable in vitro model in ecotoxicology, the results of this study indicate that the list of priority pollutants usually determined in the attempt to evaluate the risk of adverse effects to marine wildlife should be reconsidered.     

Dipyridamole-Atropine-Induced Myocardial Infarction in a Patient with Patent Epicardial Coronary Arteries

BACKGROUND: The diagnostic accuracy of the physical and pharmacological stress echocardiography tests is higher than routine exercise electrocardiography. They have an acceptable safety profile and have been rarely associated with severe adverse effects. CASE REPORT: We present a case of acute anterior myocardial reinfarction immediately after exercise and pharmacological (dipyridamole-atropine) stress echocardiography testing 1 month after successful stent implantation in LAD. Our patient was a 43-year-old man with a history of heavy smoking and hypertension. Remarkably, the stress echocardiogram was non-diagnostic few hours before the infarction occurred. Angiography performed 4 months after the reinfarction revealed neither a culprit lesion nor stent thrombosis. CONCLUSION: Aggressive "last generation" pharmacological stress testing may provide optimal diagnostic accuracy, but as in our case, complications may occur, even after negative stress testing. To our knowledge, this is the first reported case of an acute myocardial infarction as a severe complication of stress testing, which developed in a patient after stent implantation.     

Screening commercial drivers for obstructive sleep apnea: translation and validation of Serbian version of Berlin Questionnaire

Purpose

Obstructive sleep apnea (OSA) can lead to severe health consequences. Drivers of motor vehicles with untreated or undiagnosed OSA have a greater risk of traffic accidents. Use of self-reported questionnaires is the first step in OSA diagnosis. The main aim of this study was to perform the translation and validation of Berlin Questionnaire in a sample of commercial drivers.

Methods

After formal translation, validation was performed on a sample of commercial drivers and included evaluation of internal consistency, test–retest reliability, construct and criterion validity. Full-night attended polysomnography or cardiorespiratory polygraphy was used for OSA diagnosis.

Results

One hundred male participants, 24–62 years old, were included. Berlin Questionnaire classified 35 % subjects as potential OSA patients. Polysomnography confirmed OSA in 58 % of the subjects. Berlin Questionnaire showed good internal consistency (Cronbach’s alpha 0.82—first category, 0.73–0.95—second category). Test–retest reliability (Cohen’s kappa 0.78) was adequate. Berlin score was significantly correlated with OSA category and apnea–hypopnea index (AHI). Sensitivity of Berlin Questionnaire was from 50.9 (AHI ≥ 5) to 75 % (AHI ≥ 30), while specificity ranged from 86 to 70.5 %.

Conclusions

Berlin Questionnaire (Serbian version) showed good measurement properties, creating basis for further research of its usefulness as OSA screening tool in populations of interest.

     

Systemic vascular diseases in the antiphospholipid syndrome. What is the best diagnostic choice?

Antiphospholipid syndrome (APS) is an autoimmune disease which is characterized by arterial and venous thromboses, fetal loss, and the presence of antiphospholipid antibodies in the serum (aPL). It is characterized by accelerated atherosclerosis and that together with an increased tendency towards thrombosis leading to the occurrence of various vascular events. Timely diagnosis of vascular changes, preferably in subclinical phase, is required due both to their severity and to the high mortality rate. Detection of arterial and venous changes nowadays is performed through diversity of invasive and non invasive diagnostic methods. 64-multi slice computed tomographic angiography (64-MSCT) seems to be the most precise method with low exposure time, giving the opportunity for clinicians to early diagnose and timely treat APS patients.     

Anti‐ACSA‐2 defines a novel monoclonal antibody for prospective isolation of living neonatal and adult astrocytes

Astrocytes are the most abundant cell type of the central nervous system and cover a broad range of functionalities. We report here the generation of a novel monoclonal antibody, anti‐astrocyte cell surface antigen‐2 (Anti‐ACSA‐2). Flow cytometry, immunohistochemistry and immunocytochemistry revealed that Anti‐ACSA‐2 reacted specifically with a not yet identified glycosylated surface molecule of murine astrocytes at all developmental stages. It did not show any labeling of non‐astroglial cells such as neurons, oligodendrocytes, NG2⁺ cells, microglia, endothelial cells, leukocytes, or erythrocytes. Co‐labeling studies of GLAST and ACSA‐2 showed largely overlapping expression. However, there were also notable differences in protein expression levels and frequencies of single‐positive subpopulations of cells in some regions of the CNS such as cerebellum, most prominently at early postnatal stages. In the neurogenic niches, the dentate gyrus of the hippocampus and the subventricular zone (SVZ), again a general overlap with slight differences in expression levels were observed. ACSA‐2 was unlike GLAST not sensitive to papain‐based tissue dissociation and allowed for a highly effective, acute, specific, and prospective purification of viable astrocytes based on a new rapid sorting procedure using Anti‐ACSA‐2 directly coupled to superparamagnetic MicroBeads. In conclusion, ACSA‐2 appears to be a new surface marker for astrocytes, radial glia, neural stem cells and bipotent glial progenitor cells which opens up the possibility of further dissecting the characteristics of astroglial subpopulations and lineages.     

Enzymatic study of tonsil tissue alkaline and acid phosphatase in children with recurrent tonsillitis and tonsil hypertrophy

Objective

Indications for tonsillectomy in recurrent tonsillitis are defined according to the number of episodes of acute bacterial infections in a year. However, little is known about the tonsil immune competence status in patients presenting with recurrent tonsillitis with either hypertrophied or atrophied tonsils, or in patients presenting with obstructive sleep apnoea. In this study we examined the tonsil immune status in children with 3-5 acute recurrent infections a year and in children with obstructive sleep apnoea by comparing the activity of tonsil and adenoid tissue nonspecific alkaline and acid phosphatase.

Methods

Specific activity of tonsil and adenoid tissue nonspecific alkaline and acid phosphatase was investigated in children who underwent tonsillectomy and adenoidectomy for recurrent infection (72 children) and for obstructive sleep apnoea (10 children). Tissue enzyme activities were measured using p-nitrophenylphosphate as a substrate. Tissue samples were examined by the haematoxylin-eosin histological technique. Statistical analyses were performed using SPSS v. 16 software.

Results

The tissue nonspecific alkaline phosphatase activity was similar in hypertrophied tonsils in the recurrent infection group and in the obstructive sleep apnoea group (3.437 ± 1.226 and 3.978 ± 0.762 U/mg of protein, respectively). The enzyme activity in both hypertrophied tonsil groups was significantly higher as compared to atrophied tonsils in the recurrent tonsillitis group, p = 0.021 and p = 0.006, respectively. The enzyme activity was significantly higher in the adenoids compared to the tonsils from all three groups. Contrary to this, no significant differences were noticed for tonsil and adenoid acid phosphatase activities among the groups.

Conclusion

Similar acid phosphatase activity in all three groups implies that all three groups have preserved antigen presenting cell activity. In patients with hypertrophied tonsils similar tissue nonspecific alkaline phosphatase activity suggests preserved B cell tonsil immune activity, regardless of the pathology. Patients with atrophied tonsils had significantly lower alkaline phosphatase activity, indicating relative tonsil B cell immune deficiency. Thus, different immunological status in patients presenting with hypertrophied vs. atrophied tonsils could point to a different underlying pathophysiologic mechanism of the disease.