Evaluation of Marginal and Internal Adaptation of Crowns Fabricated with Three Different Zirconia CAD/CAM Materials.

BACKGROUND: Marginal and internal adaptation are key factors that determine the clinical success of dental restorations. AIM: The aim of this study is to evaluate the marginal and internal fit of crowns fabricated with three different CAD-CAM zirconia materials; two monolithic zirconia materials and one veneered zirconia copings in comparison with conventional metal-ceramic crowns. MATERIAL AND METHODS: Ninety-six extracted molars (n = 96) were selected. Teeth were randomly divided into four groups (n = 24), and the following restorations were fabricated: Metal-ceramic crowns (Control group) (Group CG); monolithic zirconia crowns (GC initial) (Group MZ1); monolithic zirconia crowns (InCoris TZI),(Group MZ2); bilayered zirconia crowns, cores (InCoris ZI) veneered with a low-fusing glass-ceramic (IPS Emax Ceram),(Group BZ). Internal and marginal adaptations were evaluated using the silicone replica technique. A total of 20 points were recorded for every tooth under the light microscope at 20x magnifications. Results were compared using one-way analysis of variance (ANOVA) and the posthoc Tukey's test at a significance level of 0.01. RESULTS: Marginal, marginal-internal, axial, and occlusal gaps between CG, MZ1, MZ2, and BZ crowns showed statistically significant differences (P < 0.01). CONCLUSION: Monolithic zirconia groups showed better marginal adaptation compared with the veneered zirconia crowns.

Risk of active tuberculosis in adult household contacts of smear-positive pulmonary tuberculosis cases.

SETTING: Seven public tuberculosis (TB) dispensaries in Istanbul, Turkey. OBJECTIVE: To investigate the risk of active TB among adult household contacts (age > or = 15 years) of newly diagnosed sputum smear-positive pulmonary TB (PTB) cases in Istanbul. DESIGN: A retrospective analysis of adult household contacts of 1570 pulmonary TB cases registered at seven TB dispensaries in Istanbul between 1997 and 2000. RESULTS: A total of 6188 household contacts (mean contact/index case: 3.9) were included in the study, of whom 4114 (67%) were aged > or = 15 years (mean contact/index case: 2.6); 3310 (80.5%) of these participated in a contact investigation. The mean duration of follow-up was 2.2 years (range 1-4 years); 222 active TB cases (rate 5.4%, 95%CI 5.2-5.6) were detected, 171 within the first year. The incidence of active TB was 2491/100 000 (3555/100 000 in the 15-34 year age group and 1195/100 000 in the > or = 35 year age group, P < 0.0001). Rates of active TB were highest in the 15-24 year (8.5%) and 25-34 year (6.5%) age groups. CONCLUSION: The incidence of active TB among adult household contacts of sputum smear-positive PTB cases was high. This high incidence justifies the prescription of chemopropylaxis not only for children but also for all contacts, especially those aged between 15 and 34 years.

Diagnosis, treatment and prognosis of carcinoid tumour of the ampulla of Vater: long-term follow-up of a case.

Carcinoid tumours of the gastrointestinal tract are most commonly localized in the appendix, followed by the small intestine and the rectum. Carcinoid tumours of the ampulla of Vater are extremely rare. In this report, we present a long-term follow-up of a new case with carcinoid tumour of the ampulla of Vater.

The effects of dimethylsulfoxide in experimental obstructive jaundice.

MATERIAL AND METHODS: Thirty rats were divided into three groups, as sham, control and DMSO groups. Laparatomy was performed on each animal in the control and DMSO groups and common bile ducts were ligated. Common bile duct was observed but was not ligated for the rats in the sham group. Saline solution injection (1.5 mg/kg/intraperitoneally (i.p.)) was begun on the first day of surgical procedure and repeated once a day for the next 5 days. The same procedure was performed with DMSO (1.5 mg/kg/i.p.) instead of saline in the DMSO group. The rats were sacrificed on the postoperative seventh day, at which time venous blood and liver tissue specimens were taken. MAIN OUTCOME MEASUREMENTS: On the 7th postoperative day, the bilirubin, AST, ALT, ALP and GGT levels of the control and DMSO groups were significantly higher in comparison with the sham group (p < 0.01). On the 7th postoperative day, the erythrocyte superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) levels of the control and DMSO groups were significantly lower than those of the sham group (p < 0.01), but there was no statistical difference between the two groups (p > 0.05). Erythrocyte and liver malondialdehyde (MDA) levels in the control and DMSO groups were significantly higher compared with the sham group (p < 0.01). However, the MDA levels were significantly lower in the DMSO group compared to the control group (p < 0.01). CONCLUSION: It is stated that free oxygen radicals seem to play a role in the liver tissue injury, secondary to obstructive jaundice. In our experimental study, exogenic DMSO seems to have decreased lipid peroxidation and to have improved some of the parameters of liver tissue injury due to the obstructive jaundice in rats.

Natural killer cell lymphoma shares strikingly similar molecular features with a group of non-hepatosplenic γδ T-cell lymphoma and is highly sensitive to a novel aurora kinase A inhibitor in vitro.

Natural killer (NK) cell lymphomas/leukemias are rare neoplasms with an aggressive clinical behavior. The majority of the cases belong to extranodal NK/T-cell lymphoma, nasal type (ENKTL) in the current WHO classification scheme. Gene-expression profiling (GEP) of 21 ENKTL and NK-cell lymphoma/leukemia patients, 17 NK- and T-cell lines and 5 indolent NK-cell large-granular-lymphocytic proliferation was performed and compared with 125 peripheral T-cell lymphoma (PTCL) patients previously studied. The molecular classifier derived for ENKTL patients was comprised of 84 transcripts with the majority of them contributed by the neoplastic NK cells. The classifier also identified a set of γδ-PTCLs both in the ENKTL cases as well as in cases initially classified as PTCL-not otherwise specified. These γδ-PTCLs expressed transcripts associated with the T-cell receptor (TCR)/CD3 complex, suggesting T cell rather than NK-cell lineage. They were very similar to NK-cell tumors by GEP, but were distinct from cytotoxic (αß)-PTCL and hepatosplenic T-cell lymphoma, indicating derivation from an ontogenically and functionally distinct subset of γδ T cells. They showed distinct expression of Vγ9, Vδ2 transcripts and were positive for TCRγ, but negative for TCRß by immunohistochemistry. Targeted inhibition of two oncogenic pathways (AURKA and NOTCH-1) by small-molecular inhibitors induced significant growth arrest in NK-cell lines, thus providing a rationale for clinical trials of these inhibitors in NK-cell malignancies.

Genomic analyses reveal global functional alterations that promote tumor growth and novel tumor suppressor genes in natural killer-cell malignancies.

Natural killer (NK)-cell malignancies are among the most aggressive lymphoid neoplasms with very poor prognosis. We performed array comparative genomic hybridization analysis on a number of NK cell lines and primary tumors to gain better understanding of the pathogenesis and tumor biology of these malignancies. We also obtained transcriptional profiles of genes residing in these regions and compared them with normal and activated NK cells. Only 30-50% of the genes residing in the gained or deleted regions showed corresponding increased or decreased expression. However, many of the upregulated genes in regions of gain are functionally important for the proliferation and growth of the neoplastic population. Genes downregulated in regions of loss included many transcription factors or repressors, tumor suppressors or negative regulators of the cell cycle. The minimal common region of deletion in 6q21 included three known genes (PRDM1, ATG5 and AIM1) showing generally low expression. Mutations resulting in truncated PRDM1 and changes in conserved amino-acid sequences of AIM1 were detected. Highly methylated CpG islands 5' of PRDM1 and AIM1 correlated with low expression of the transcripts. Reversal of methylation by Decitabine induced expression of PRDM1 and cell death. In conclusion, we have shown a general tumor-promoting effect of genetic alterations and have identified PRDM1 as the most likely target gene in del6q21. ATG5, an essential gene for autophagy and AIM1, a gene implicated in melanoma, may also participate in the functional abnormalities.

Survival and symbiotic effectivity of lyophilized root nodule bacteria.

The study has been carried out under the greenhouse and laboratory conditions, using the lyophilization technique to determine the preserving possibilities of 3 native strain isolated from bean root nodules that been widely cultivated in Turkey and was defined as Rhizobium bacteria. The strains been developed separately in the Petri dishes with YMA (Yeast Extract Mannitol Agar) sown into lyophilization tubes containing skim milk, frozen at -85 degrees C and dehydrated at -55 degrees C with vacuum. According to the cultural counting results continued for 35 months after lyophilization, while the living cells in R11 strains and R12 strains found as 41 x 10(9) and 35.5 x 10(9) cell mL(-1), respectively, the best result was determined in the R13 strain as 51.5 x 10(9) cell mL(-1). In the greenhouse trials, the dry weight of plant's green parts, the number of nodules and total nitrogen amounts were evaluated. The tested strains were inoculated with bean varieties peculiar to themselves and the lyophilizated cultures gave similar results with the main cultures kept in tubes with YMA.

Effect of interleukin-10 on pancreatic damage caused by organophosphate poisoning.

Organophosphate poisoning is a common cause of severe morbidity and mortality in emergency departments. Acute pancreatitis is a frequently reported consequence of organophosphate poisoning, but preventing this potentially severe complication has not been the subject of much research. We tested whether interleukin-10, a cytoprotective agent, could prevent or diminish pathological signs of acute pancreatitis caused by organophosphate poisoning. Thirty rats were divided into three equal groups. Group 1 did not receive any agent during the experiment. Group 2 received 0.8 g/kg fenthion intraperitoneally, followed by 6 ml/kg intraperitoneal normal saline 30 min and 3 h later. Group 3 received 0.8 g/kg fenthion intraperitoneally, followed by 2 microg/kg of interleukin-10 intraperitoneally 30 min and 3 h later. All rats underwent laparotomy and thoracotomy while still under anesthesia at 6 h, and tissue samples were obtained from the pancreas. After blood samples were taken by cardiac puncture, the animals were sacrificed. Organophosphate poisoning resulted in significant elevations of serum amylase and glucose. Interleukin-10 significantly reduced pancreatic damage as determined by pathologic scoring, but not by enzyme elevations. Interleukin-10 should be considered for larger studies in other animal models to confirm its ability to decrease pancreatic damage after organophosphate poisoning treatment with interleukin-10.

Role of oxygen free radical scavengers in acute renal failure complicating obstructive jaundice.

Obstructive jaundice is associated with high morbidity and mortality. Major complications such as pulmonary dysfunction, renal failure and sepsis are frequently encountered. Recent studies and observations suggest that the free oxygen radicals (FORs) produced in obstructive jaundice may play a significant role in the etiopathogenesis of acute renal failure (ARF). Thirty rats were divided into three groups, as sham, control and treatment groups containing 10 rats each. Laparatomy was performed on each animal in the control and treatment groups and common bile ducts were ligated. Common bile duct was observed but was not ligated for the rats in the sham group. Saline solution injection was begun on the first day of surgical procedure and repeated once a day during the following 5 days. The same procedure was performed with oxygen radical scavenger dimethyl sulfoxide (1.5 mg/kg/day i.p.) instead of saline in the treatment group. The rats were sacrificed on the 7th postoperative day. On the 7th postoperative day, the bilirubin, urea and creatinine levels of the control and treatment groups were significantly higher in comparison with the sham group (p < 0.01). Although there was no statistically significant difference between the bilirubin levels of the control and treatment groups (p > 0.05), the urea and creatinine levels in the treatment group were significantly lower (p < 0.01). On the 7th postoperative day, the erythrocyte superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) levels of the control and treatment groups were significantly lower than those of the sham group (p < 0.01), whereas renal and erythrocyte malondialdehyde (MDA) levels were significantly higher (p < 0.01). Although SOD and GSH-Px levels did not differ significantly between the treatment and control groups (p > 0.05), renal and erythrocyte MDA levels of the treatment group were significantly lower than those of the control group (p < 0.01). The histopathological scores were significantly higher in the control and treatment groups (p < 0.01); there was no significant difference between the control and treatment groups (p > 0.05). FORs seem to play a significant role in the etiopathogenesis of renal failure in obstructive jaundice. Antioxidant treatment may decrease oxidative damage due to FORs and may prevent renal failure.