A stereological study of the effects of mercury inhalation on the cerebellum

Mercury in the environment that arises from organic and inorganic sources can cause irreversible damage to the nervous system. Toxicity may be direct or may arise from interactions with other metals in the environment. We evaluated the possible effects of mercury vapor on rat cerebellum. Twelve adult female rats were divided into control and experimental groups. The rats in the experimental group were exposed to mercury vapor for 9 h/day for 45 days. Cerebellar tissue samples were evaluated using stereology and for histopathology. The total number of Purkinje cells was estimated using a physical disector method. We found that in the experimental group, overall volume decreased and the number of Purkinje cells was reduced. We also found cellular damage including pycnotic nuclei, eosinophilic cytoplasm and vacuolization; these features were absent in the control group. We found that chronic exposure to inorganic mercury vapor is toxic to the cerebellum

Inhalation of mercury vapor can cause the toxic effects on rat kidney

Dental amalgam has been used in dentistry as a filling material. The filler comprises mercury (Hg). It is considered one of the most important and widespread environmental pollutants, which poses a serious potential threat for the humans and animals. However, mercury deposition affects the nervous, cardiovascular, pulmonary, gastrointestinal, and especially renal systems. In most animals' species and humans, the kidney is one of the main sites of deposition of mercury and target organ for its toxicity. In this study, the effects of mercury intake on kidney in rats were searched. For the this purpose; we used 24 adult female Wistar albino rats (200g in weight) obtained from Experimental Research and Application Center of Ataturk University with ethical approval. Besides, they were placed into a specially designed glass cage. Along this experiment for 45 days, subjects were exposed to (1mg/m(3)/day) mercury vapor. However, no application was used for the control subjects. At the end of the experiment, kidney samples were obtained from all subjects and processed for routine light microscopic level and stereological aspect were assessed. Finally, according to our results, mercury affects the histological features of the kidney. That means, the severe effects of mercury has been shown using stereological approach, which is one of the ideal quantitative methods in the current literature. In this study, it was detected that chronic exposure to mercury vapor may lead to renal damage and diseases in an experimental rat model

Effect of mercury vapor inhalation on rat ovary: stereology and histopathology

AimMercury, an environmental contaminant, is a risk factor for health in whole living organisms. In this study, we investigated whether mercury vapor (HgO) inhalation has an effect on rat ovary. MethodsTwelve Wistar albino rats were divided equally into experimental (Hg) and control groups (n = 6). Animals in the Hg group were exposed to HgO for 45 days at a dose 1 mg/m(3)/day, after which, histological and stereological assessment were carried out. ResultsOvaries exposed to HgO had histo-morphometric alterations. HgO inhalation resulted in reduction of the total number of primordial, primary and Graaf follicles. Also, mean volume of ovary, medulla and cortex, corpus luteum (c.luteum) and Graaf follicles was decreased in the Hg group. Moreover, there was a significant increase in total volume of the atretic follicles. On light microscopy, thickening of tunica albuginea, increase of fibrils within the connective tissue, congestion of the capillaries and venous vessels, thinned walls and fibrin deposition in some large blood vessels, and edema were seen. Also, irregular follicle and oocyte borders, and hydropic degeneration in follicular granulosa cells were detected. ConclusionStructural alterations could be attributed to the toxic influence of HgO on rat ovary. The use of Hg should therefore be more controlled to minimize its toxic effect

A stereological and histopathological study of the effects of exposure of male rat testes to mercury vapor

Mercury is ubiquitous in the environment; it is an occupational pollutant and a potential toxicant. We investigated the effects of exposure of rat testes to mercury vapor (Hg-0). Twelve male rats were divided into two groups of six: the rats of the Hg-0 group were exposed to mercury (1 mg/m(3)/day) in a chamber for six weeks; the control group rats were housed under the same conditions without exposure to Hg-0. After the experimental period, the testes were removed, sections of testis were evaluated histopathologically after hematoxylin and eosin staining, and stereologically using the Cavalieri principle and optical fractionator methods. We found significant decreases in the total volume of testis, diameters of seminiferous tubules and total volume of seminiferous tubules. Significant decreases were detected in the numbers of Sertoli cells, spermatogonia, spermatocytes and spermatids of the Hg-0 group compared to the control group. In the Hg-0 exposed group, spermatogenic cells were degenerated and seminiferous tubules were atrophied.This study was supported by Ataturk University Scientific Project Fun

Comparison of the translucency of two multishaded composite resins polymerized with direct or indirect method

The aim of this study was to measure the translucency of one indirect and direct resin composite after polymerization and to examine the effect of color parameters on this property. Tescera and Filtek Ultimate, each containing three shade groups (Enamel, Dentin and Body for Filtek Ultimate; and Incisal, Opaceous Dentin and Body for Tescera), were investigated. The translucency parameter (TP) was measured as the color difference between a specimen over a white and black background. Significant differences were observed in TP values between shade groups. Tukey’s multiple comparison test revealed TP values among the groups of Filtek Ultimate-Enamel > Tescera-Incisal > Filtek Ultimate-Body > Tescera-Body = Filtek Ultimate-Dentin > Tescera-Opaceous Dentin. In conclusion, it is concluded that the translucency of resin composite was affected by polymerization and color parameters

Effects of composite restorations on nitric oxide and uric acid levels in saliva

Background and Aims: Dental materials that are used in dentistry should be harmless to oral tissues, and should, therefore, not contain any leachable toxic and diffusible substances capable of causing side effects. This study was intended to investigate the effects on salivary nitric oxide (NO) and uric acid (UA) levels after application of dental composite filling materials to healthy volunteers. Materials and Methods: A total of 52 individuals (32 female and 20 male) participated in the study. Filtek Z250 composite filling material (3M ESPE, St Paul, MN, USA) was applied to healthy volunteers. Saliva samples were collected before restoration (baseline) and 1 h, 1-day, 7 days, and 30 days after restoration. NO concentrations were measured using the Griess reaction method, and UA was measured using an enzymatic method. Data were analyzed using repeated measures ANOVA and the Bonferroni post-hoc test (α =5%). Results: NO values increased statistically significant after 7 days (P 0.05). There was no correlation between NO and UA levels in saliva (P > 0.05). Conclusion: Composite resins activated the antioxidant system in saliva. However, further studies are now needed to confirm our findings and to permit a definitive conclusion

1-4Comparison of the Antibacterial Efficacy of Several Dentin Bonding Agents: Two Different in Vitro Studies

Abstract Objective: In this study, we compared the antibacterial effects of several dentin bonding agents with different pH values and active monomers. Method and Materials: Infected dentin samples were obtained from depths of approximately 4-6 mm, from isolated and air-dried dental caries. Streptococcus mitis was isolated and incubated on sheep blood agar plates at 37°C for 18 h. Impregnated antimicrobial disks were used for the liquids, and the samples were grouped as follows: group 1 was a negative control group with nothing applied; group 2 was a positive control group with 2% chlorhexidine digluconate applied; group 3 had Adper Single Bond Universal applied; group 4 had Clearfil SE Bond 2 (including 10-methacryloyloxydodecyl dihydrogen phosphate[MDP]) applied; group 5 had Clearfil S3 Bond Plus (including [MDP])applied; and group 6 had Clearfil Protect Bond (including 12-methacryloyloxydodecylpyridinium bromide [MDPB])applied. The antimicrobial disks were inserted into the blood agar plates. Inhibition zones were measured on the plates by well-educated specialists. Results: The 2% chlorhexidine digluconate solution had a more extensive inhibition zone than the other groups. S. mitis was significantly inhibited on the MDPB-impregnated disks applied to the agar plates. Conclusions: The results demonstrated that dentin bonding agents including MDPB-containing primer had significant antibacterial effects

Stężenie troponiny I oznaczane metodą wysokoczułą u chorych z wolnym przepływem wieńcowym

Hypothesis: We examined the hypothesis that a specific myocardial injury marker, namely high sensitive cardiac troponin-I (HsTn-I), is elevated in patients with slow coronary flow (SCF) pattern.Aim: To examine the above hypothesis by studying a group of patients who had undergone coronary angiography for the detection of their chest pain aetiology with SCF pattern despite an angiographically normal coronary arteriogram.Methods: We evaluated and performed coronary angiography (CAG) of 97 patients with chest discomfort. The indication forCAG was at least Canada class 3 angina and/or proven myocardial ischaemia according to noninvasive diagnostic tests. We further divided patients into three subgroups according to CAG images and compared HsTn-I plasma levels in 39 patients with SCF pattern, 28 patients with coronary artery disease (CAD), and 30 patients with normal coronary arteries. We researched the association between qualitative HsTn-I positivity and demographic features including cardiovascular risk factors, inflammation markers and TIMI frame count for each of the epicardial coronary arteries.Results: TIMI frame count for each epicardial coronary artery was significantly higher in patients with SCF pattern than in patients with CAD and normal coronary arteries (p < 0.001). HsTn-I positivity was not statistically different between patients with SCF pattern and normal coronary arteries (p = 512), but it was significantly higher in the CAD group than the other two group of patients (p < 0.001).Conclusions: In patients with SCF, HsTn-I may be detectable, but it is not elevated as in patients with normal coronary arteries.Wstęp: Autorzy sprawdzili hipotezę, że swoisty wskaźnik uszkodzenia mięśnia sercowego, stężenie sercowej troponiny I oznaczone metodą wysokoczułą (HsTn-I), jest podwyższone u chorych z wolnym przepływem wieńcowym.Cel: Zbadanie powyższej hipotezy w grupie chorych poddanych koronarografii w celu ustalenia przyczyny bólu w klatce piersiowej, u których przy prawidłowym obrazie angiograficznym naczyń wieńcowych współistniał wolny przepływ wieńcowy.Metody: U 97 chorych z objawami dyskomfortu w klatce piersiowej przeprowadzono ocenę kliniczną i koronarografię. Wskazaniami do koronarografii były: co najmniej 3. stopień w skali nasilenia objawów dławicowych Kanadyjskiego Towarzystwa Kardiologicznego (CCS) i/lub niedokrwienie mięśnia sercowego potwierdzone w badaniach nieinwazyjnych. Następnie podzielono pacjentów na 3 grupy w zależności od wyników koronarografii i porównano stężenia HsTn-I w osoczu u 39 chorych z wolnym przepływem wieńcowym, 28 pacjentów z chorobą wieńcową (CAD) i 30 osób z prawidłowym obrazem tętnic wieńcowych. Przeanalizowano zależności między dodatnim wynikiem oznaczenia HsTn-I (zmienna jakościowa) a parametrami demograficznymi obejmującymi m.in. czynniki ryzyka sercowo-naczyniowego, wskaźniki zapalenia i ocenę przepływu w skali TIMI dla każdej tętnicy nasierdziowej.Wyniki: U pacjentów z wolnym przepływem wieńcowym punktowa ocena w skali TIMI była istotnie wyższa niż u osób z chorobą wieńcową i z prawidłowym obrazem tętnic wieńcowych w przypadku każdej tętnicy nasierdziowej (p < 0,001). Nie było statystycznie istotnych różnic w zakresie częstości dodatnich wyników oznaczenia HsTn-I miedzy pacjentami z wolnym przepływem wieńcowym a osobami z prawidłowym obrazem tętnic wieńcowych (p = 512). Dodatni wynik oznaczenia HsTn-I stwierdzano natomiast istotnie częściej w grupie osób z CAD niż w pozostałych grupach pacjentów (p < 0,001).Wnioski: U chorych z wolnym przepływem wieńcowym HsTn-I może być wykrywalna, ale jej stężenie może się utrzymywać w granicach normy, podobnie jak u osób z prawidłowymi tętnicami wieńcowymi