The role of NMDA glutamate receptors in lung injury caused by chronic long-term intermittent hypobaric hypoxia.

Chronic intermittent hypoxia (CIH), a component of sleep apnea-hypopnea syndrome, is suggested to cause damage to lung tissue, and the role of glutamate is not well studied. We used a chronic long-term intermittent hypobaric hypoxia (CLTIHH) model of rats to find out if such procedure causes lung injury and the potential effect of N-methyl-D-aspartate receptors (NMDARs) by using receptor antagonist MK-801 (dizocilpine). Thirty-two rats were placed into four groups; a control and three CLTIHH groups where rats were placed into a low-pressure chamber set to 430 mmHg for 5 h/day, 5 days/week, for 5 weeks. Only one group received MK-801 (0.3 mg/kg, ip) daily. We evaluated tumor necrosis factor (TNF)-α, interleukin (IL)-6, IL-10, and nuclear factor (NF)-kB for the inflammatory process, superoxide dismutase (SOD), malondialdehyde (MDA), catalase (CAT), glutathione peroxidase (GPX), total antioxidant status (TAS), and total oxidant status (TOS) for oxidative stress, and caspase-9 levels. Blood plasma, bronchoalveolar fluid (BALF), and lung tissue extracts were evaluated. Both oxidant and inflammatory parameters were significantly increased in all the mediums of the CLTIHH groups except the group that received MK-801. Significant evidence was collected on MK-801 alleviating the effect of CLTIHH. Histological evaluations revealed lung damage and fibrotic changes in the CLTIHH groups. It was first shown that the CLTIHH procedure caused chronic lung injury, and that inflammation and oxidant stress were influential in the formation of lung injury. Secondly, NMDAR antagonist MK-801 effectively inhibited the development of lung injury and fibrosis.

The role of NMDA glutamate receptors in lung injury caused by chronic long-term intermittent hypobaric hypoxia

Chronic intermittent hypoxia (CIH), a component of sleep apnea-hypopnea syndrome, is suggested to cause damage to lung tissue, and the role of glutamate is not well studied. We used a chronic long-term intermittent hypobaric hypoxia (CLTIHH) model of rats to find out if such procedure causes lung injury and the potential effect of N-methyl-D-aspartate receptors (NMDARs) by using receptor antagonist MK-801 (dizocilpine). Thirty-two rats were placed into four groups; a control and three CLTIHH groups where rats were placed into a low-pressure chamber set to 430 mmHg for 5 h/day, 5 days/week, for 5 weeks. Only one group received MK-801 (0.3 mg/kg, ip) daily. We evaluated tumor necrosis factor (TNF)-α, interleukin (IL)-6, IL-10, and nuclear factor (NF)-kB for the inflammatory process, superoxide dismutase (SOD), malondialdehyde (MDA), catalase (CAT), glutathione peroxidase (GPX), total antioxidant status (TAS), and total oxidant status (TOS) for oxidative stress, and caspase-9 levels. Blood plasma, bronchoalveolar fluid (BALF), and lung tissue extracts were evaluated. Both oxidant and inflammatory parameters were significantly increased in all the mediums of the CLTIHH groups except the group that received MK-801. Significant evidence was collected on MK-801 alleviating the effect of CLTIHH. Histological evaluations revealed lung damage and fibrotic changes in the CLTIHH groups. It was first shown that the CLTIHH procedure caused chronic lung injury, and that inflammation and oxidant stress were influential in the formation of lung injury. Secondly, NMDAR antagonist MK-801 effectively inhibited the development of lung injury and fibrosis.

Evaluation of push-out bond strength of a new MTA-based sealer.

AIM: To evaluate the push-out bond strength of MTA Fillapex (Angelus) and compare it with ProRoot MTA (Dentsply) and AH Plus (Dentsply). DESIGN: Thirty extracted single-rooted teeth were selected and prepared using a rotary system. The samples were divided randomly into three groups (n = 10) and obturated, respectively, with: (1) AH Plus + gutta-percha (DiaDent); (2) MTA Fillapex + gutta-percha; (3) ProRoot MTA. Each root was sectioned into 1-mm-thick slices and 30 samples for each group were obtained. The samples were subjected to push-out test. Failure modes were examined under 30× magnification. The results were analysed statistically by one-way ANOVA and Tukey's test. RESULTS: Mean push-out bond strength values were ranked as follows: ProRoot MTA > AH Plus > MTA Fillapex. Statistically significant differences were found among all groups (p < 0.05). CONCLUSION: ProRoot MTA had the highest bond strength, whilst MTA Fillapex displayed the lowest values among the groups.

In vitro evaluation of apical microleakage of a new MTA-based sealer.

AIM: To evaluate the apical microleakage of a new MTAbased sealer; MTA Fillapex (Angelus) and compare it with ProRoot MTA (Dentsply) and AH Plus (Dentsply). METHODS: 51 single-rooted permanent teeth were selected and the roots were prepared using a rotary system. The samples were divided randomly into 3 groups (n=15). Six roots were used as positive and negative controls. The teeth were obturated with respectively; A. AH Plus and gutta percha (DiaDent); B. MTA Fillapex and gutta percha; C. ProRoot MTA. Specimens were placed in 2% methylene blue dye for 72h. Then linear dye penetration was measured. Measurements were analysed statistically. RESULTS: MTA Fillapex group had significantly higher microleakage values (p<0.05). There were no statistically significant differences between MTA and AH Plus groups (p>0.05). CONCLUSION: The sealing ability of AH Plus and MTA were similar whilst MTA Fillapex showed more microleakage than the other two materials.

Supporting language and cognitive development of infants and young children living in children's homes in Turkey.

AIM: The purpose of the present study was to improve language and cognitive development of infant and young children residing in institutional settings in Turkey. METHOD: In Study I, there were 12 children with a mean age of 35 months in the intervention group and 12 children with a mean age of 36 months in the control group. RESULTS: When both groups' pre-test post-test general development t scores and cognitive and language sub-domain developmental gaps were compared, neither the time nor the time by group interactions were significant. Nevertheless, both groups' developmental gap appeared to decline. In Study II, children were recruited from the same institution and randomly assigned to the intervention and control groups. Results indicated that infants and children who were in the intervention group showed a decline in the language and cognitive development gaps, whereas the control group children's developmental gaps were increased. CONCLUSIONS: It can be concluded that by increasing the quality of care in children's homes infants' and young children's development can be enhanced.

Success rate of calcium hydroxide pulpotomy in primary molars restored with amalgam and stainless steel crowns.

OBJECTIVES: To compare the success rate of calcium hydroxide (Ca(OH)(2)) pulpotomies in primary molars restored with a stainless steel crown (SSC) to that of teeth restored with amalgam and to evaluate the role of restoration failure in treatment outcome. STUDY DESIGN: Pulpotomies were performed in 154 primary molars. Teeth were grouped according to pulpal exposure type as either mechanically or cariously exposed, with cariously exposed teeth further divided according to size of exposure site (pinpoint or larger than pinpoint). Seventy teeth were restored with amalgam and 84 with a SSC. Teeth were followed up for 12 months. RESULTS: Pulpotomy success rates were 79.9% for teeth restored with a SSC and 60% for those restored with amalgam. The difference between these rates was statistically significant (p <0.01). Restoration failure rates were 14.3% for amalgams and 2.4% for SSCs. The difference between these rates was also statistically significant (p <0.01). Among the 12 failed restorations, treatment was found to be successful in five cases (41.7%) and unsuccessful in seven cases (58.3%). This difference was not statistically significant (p >0.05). CONCLUSIONS: The pulpotomy success rate for teeth restored with a SSC was higher than for those restored with amalgam. Restoration failure did not appear to have an effect on treatment prognosis.

Treatment of an avulsed maxillary permanent central incisor by autotransplantation of a primary canine tooth.

AIM: To present a case in which an avulsed permanent maxillary central incisor was replaced by autotransplantation of a primary canine tooth. SUMMARY: The present case describes transplantation of a primary canine tooth into the space left by an avulsed permanent maxillary central incisor after a delay of several days. After root canal treatment, the primary canine tooth was extracted and placed into the prepared socket. To provide better adaptation of the donor tooth, the recipient alveolar site was remodeled using surgical burs. Semi-rigid splinting was maintained for 15 days. The crown of the primary canine was reshaped with composite resin and with an interim prosthesis, preventing movement of the lateral incisor tooth into the space of the transplanted canine. After 24-month follow-up the autotransplanted primary canine showed ankylosis but the tooth was in an acceptable state. The use of permanent tooth autotransplantation has been well documented. However a literature search revealed only one case report on the autotransplantation of primary teeth. KEY LEARNING POINTS: Long term results of primary tooth autotransplantation are scarce but the procedure in this case report could be considered as a temporary space maintainer for the treatment of a patient with a lost permanent incisor under 10 years of age. Success of primary tooth autotransplantation may be affected by several factors, such as case selection, extra oral time, surgical and endodontic procedures.

Altered CD45 isoform expression in C77G carriers influences cytokine responsiveness and adhesion properties of T cells.

The C77G polymorphism in exon A of the human CD45 gene occurs with low frequency in healthy individuals. An enhanced frequency of C77G individuals has been reported in cohorts of patients suffering from multiple sclerosis, systemic sclerosis, autoimmune hepatitis, hepatitis C and human immunodeficiency virus (HIV)-1. C77G individuals overexpress CD45RA isoforms on activated/memory T cells. We have shown previously that aberrant expression of CD45RA isoforms enhances the intensity of T cell receptor (TCR) signalling. Here we report that the C77G polymorphism also influences the responsiveness of T cells to cytokines and alters their adhesion properties. When stimulated by interleukin (IL)-2, C77G T cells proliferated more strongly than wild-type controls and showed accelerated phosphorylation of Janus kinase (Jak1). Furthermore, C77G T cells exhibited a higher tendency to form homotypic aggregates in culture which could be enhanced significantly by antibody-mediated triggering of the variant CD45RA molecules. These data indicate that the changes in CD45 isoform combination resulting from C77G may not only affect TCR signalling but also cytokine-driven T cell responses and cellular adhesion. Altered immune responsiveness may enhance susceptibility of C77G carriers for certain diseases.

Methenamine silver staining quantitative digital histochemistry in chronic allograft nephropathy.

Renal function and final outcome of renal allografts have been correlated with irreversible damage. This study describes a quantitative histochemical method relying on periodic acid methenamine silver (PAMS) staining of all renal compartments. Among 60 renal allograft biopsies from 43 patients, 15 biopsies showing pure chronic allograft nephropathy were selected to determine PAMS-stained area percentage (SAP), using image analysis with quantitative histochemistry. Of the 15 cases, 9 (60%) were grade I and 6 (40%) were grade II chronic allograft nephropathy (CAN). The mean serum creatinine (sCr) value was 1.86 +/- 0.47 for allograft biopsies. The mean (+/-SD) SAP for the implantation biopsies was 10.58 +/- 1.87%, and for allograft biopsies 25.26 +/- 9.67 (P <<.000). The serum creatinine (sCr) values for grade I versus II CAN were 1.63 +/- 0.24 versus 2.20 +/- 0.54 mg/dL, respectively (P=.019), and SAP values were 18.97 +/- 0.24 versus 34.7 +/- 5.89 (P=.003). There was a strong positive correlation between sCr values and SAP (P=.005; r=0.64). These findings show the PAMS approach to be a useful alternative method for reflecting damage in more than one compartment of the renal tissue. Also, the method can discriminated implantation and allograft biopsies as well as grade I and II CAN cases. The series is small for a multivariate analysis of the value of SAP measurements in PAMS-stained sections as a prognosticator, but the data support its use.

Glatiramer acetate (GA) induces IL-13/IL-5 secretion in naive T cells.

In order to define possible mechanisms of immunomodulation by glatiramer acetate (GA), we investigated the primary in vitro cytokine response of peripheral blood mononuclear cells (PBMCs) and T-cell subpopulations. In PBMCs from healthy subjects and untreated patients with multiple sclerosis (MS) GA-induced T-cell proliferation and mRNA expression/cytokine, secretion of IL-13 and IL-5 but not of IL-10, TGF-beta or IL-12, IL-4 was detected at the mRNA level only. IFN-gamma was induced in a few subjects at very low concentrations. The response to GA was driven by the CD4(+)/CD45RA(+) T-cell subpopulation and was mediated by T-cell receptor (TCR) engagement as determined by anti-TCR blocking antibodies. The findings are compatible with the hypothesis that GA functions as partial or weak TCR-agonist activating naive T cells to produce the Th2 cytokines IL-13 and IL-5.