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1.
BACKGROUND: The aim of the present study was 1) to evaluate the possible effects of therapeutic usage of omega-3 fatty acid on the gingival tissue levels of prostaglandin E2 (PGE2), prostaglandin F2alpha (PGF2alpha), platelet activating factor (PAF), and leukotriene B4 (LTB4) in endotoxin-induced periodontitis in rats and 2) to investigate whether prophylactic usage provides any additional benefits to therapeutic doses of omega-3 fatty acid. METHODS: Experimental periodontitis was induced by repeated injection of Escherichia coli lipopolysaccharide (LPS). Thirty-six adult male Sprague-Dawley rats were divided into four study groups: 1) saline controls; 2) LPS; 3) therapeutic omega-3 fatty acid (TO3); and 4) prophylactic plus therapeutic omega-3 fatty acid (P + TO3) groups. In TO3 group, omega-3 fatty acid was given for 15 days following induction of experimental periodontitis. In P + TO3 group, omega-3 fatty acid was started 15 days before baseline, and then periodontitis was induced at baseline and omega-3 fatty acid was continued for 15 days after baseline. On day 15 after baseline, all rats were anesthetized and sacrificed. PGE2, PGF2alpha, and LTB4 levels in gingival tissue samples were analyzed by enzyme immunoassay and PAF levels were analyzed by radioimmonoassay. Data were evaluated statistically by using parametric tests. RESULTS: LPS injection resulted in significant amount of bone loss (P<0.05). Neither therapeutic nor prophylactic plus therapeutic administration of omega-3 fatty acid with the doses and duration of therapy used in the present study was effective in preventing endotoxin-induced alveolar bone loss. TO3 group exhibited significant decreases in the gingival tissue levels of PGE2, PGF2alpha, LTB4, and PAF compared to the LPS group (P<0.05). PGE2 and PGF2alpha levels in TO3 group were similar to those of the saline group (P>0.05), while LTB4 and PAF levels were statistically higher than the saline group (P<0.05). Prophylactic plus therapeutic usage of omega-3 fatty acid provided similar levels of all these mediators to those of the saline controls (P>0.05). CONCLUSIONS: Therapeutic omega-3 fatty acid significantly reduced the gingival tissue levels of PGE2, PGF2alpha, LTB4, and PAF in experimental periodontitis. Furthermore, prophylactic usage of omega-3 fatty acid provided additional beneficial effects to the therapeutic administration by decreasing the gingival tissue levels of these mediators to levels of healthy tissue. These findings should be verified by longitudinal clinical trials investigating clinical and biochemical periodontal parameters to better define the possible role of omega-3 fatty acids in periodontal treatment.  相似文献   
2.
BACKGROUND: The aim of the present study was to investigate the total proteoglycan (PG) and chondroitin-4-sulfate (C4S) levels in gingival tissue samples obtained from patients with aggressive periodontitis (AgP) and chronic periodontitis (CP) before therapy (baseline) and 1 month after completion of non-surgical periodontal therapy. METHODS: Gingival tissue samples were obtained from 10 AgP and 10 CP patients before initiation of treatment (baseline) and 1 month after non-surgical periodontal treatment. The control group comprised 10 systemically and periodontally healthy subjects. Total PG and C4S levels were determined by biochemical techniques. PG levels were analyzed using a modified Bitter and Muir method. C4S assay was carried out using chondroitin sulphate lyase AC and chondroitin-6 sulphate sulphohydrolase enzymes. The results were tested statistically using parametric tests. RESULTS: The clinical periodontal parameters demonstrated significant decreases in the periodontitis groups (P<0.05) after treatment, and there was no significant difference between AgP and CP groups at baseline and after treatment (P>0.05). At baseline, total PG and C4S levels in both of the periodontitis groups were significantly lower than that of the control group (P<0.05). One month after the non-surgical periodontal treatment, total PG levels in the periodontitis groups were comparable to the control group (P>0.05), whereas C4S levels in the AgP group were significantly lower than the other study groups (P<0.05). In the CP group, total PG and C4S levels increased significantly (P = 0.001 and P = 0.006, respectively) after non-surgical periodontal treatment, but they did not increase in the AgP group (P>0.05). CONCLUSION: The significant increases observed in total proteoglycan and chondroitin-4-sulfate levels after non-surgical periodontal treatment in the CP group but not in the AgP group may suggest that healing patterns differ between the two periodontitis types in terms of PG and C4S composition of extracellular matrix.  相似文献   
3.

Purpose

Natural killer (NK) cells express killer immunoglobulin-like receptors (KIRs) which recognize HLA class I molecules on trophoblasts. KIRs could either activate NK cells or inhibit them to produce soluble factors necessary for the maintenance of pregnancy, thus they are suspected of being involved in the causes of recurrent miscarriage. The aim of this study was to evaluate whether there is any possible association between KIR genes, genotypes and recurrent miscarriage.

Methods

The present study was carried out on 40 women who had unexplained recurrent miscarriage and 90 controls. Sequence-specific oligonucleotide probes analysis were used to investigate 16 KIR genes. All data were statistically analyzed by Fisher Exact Test.

Results

The rate of Bx genotypes that consists elevated number of activating KIR genes was significantly higher (p = 0.014) in women with recurrent miscarriage when compared with the control group. Additionally, the frequency of AA genotype (AA1) of the subjects in the study group was significantly lower than the frequency of the subjects in the control group (p = 0,014). Furthermore, there were no statistically significant differences in the frequencies of the individual KIR genes between women with recurrent miscarriage and the control group.

Conclusions

Inclined balance of KIRs toward an activating state in NK cells may contribute to recurrent miscarriage.  相似文献   
4.
5.
Technetium-99m HMPAO brain SPECT in autistic children and their families   总被引:2,自引:0,他引:2  
The purpose of the study was to investigate perfusion patterns in autistic children (AC) and their families. Ten AC (9 boys, 1 girl; mean age: 6.9+/-1.7 years) with autistic disorder defined by DSM-III-R criteria, five age-matched children (3 boys, 2 girls) as a control group, and the immediate family members of eight AC (8 mothers, 8 fathers, 7 siblings; mean ages: 39+/-4 years, 36+/-5 years and 13+/-5 years, respectively) were included in the study. Age- and sex-matched control groups for both the parents and the siblings were also included in the study. Brain perfusion images were obtained 1 h after the intravenous injection of an adjusted dose of Tc-99m HMPAO to children and the adults. Visual and semiquantitative evaluations were performed. Hypoperfusion was seen in the right posterior parietal cortex in three AC, in bilateral parietal cortex in one AC, bilateral frontal cortex in two AC, left parietal and temporal cortex in one AC, and right parietal and temporal cortex in one AC. Asymmetric perfusion was observed in the caudate nucleus in four AC. In semiquantitative analyses, statistically significant hypoperfusion was found in the right inferior and superior frontal, left superior frontal, right parietal, right mesial temporal and right caudate nucleus. In parents of AC, significant hypoperfusion was noted in the right parietal and bilateral inferior frontal cortex. In siblings of AC, perfusion in the right frontal cortex, right nucleus caudate and left parietal cortex was significantly decreased. This preliminary study suggests the existence of regional brain perfusion alterations in frontal, temporal, and parietal cortex and in caudate nucleus in AC and in their first-degree family members.  相似文献   
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7.
Spinal cord dissemination over 10 years after surgical removal of the fourth ventricle ependymoma without local recurrence is extremely rare. A 49-year-old male underwent a macroscopically gross total removal of the fourth ventricle ependymoma and postoperative radiotherapy to the posterior fossa. Twelve years after the initial operation, the patient complained from uncontrolled fever attacks, low back pain and numbness of the legs. Spinal Magnetic Resonance Imaging revealed intradural extramedullary mass lesions located at the thoracic 2-3 and lumbar 5 vertebrae levels. Cerebrospinal fluid examination showed no tumour cells. He underwent total excision of these spinal lesions. Although the majority of the recurrences take place within a few years after surgery, we experienced a case with multiple spinal disseminations 12 years after the resection of the fourth ventricle ependymoma and administration of the radiation therapy to the posterior fossa. Up to our knowledge, this case represents the second unusual late recurrence reported in the literature. We conclude that low grade ependymomas should be followed neurologically and radiologically for more than 10 years after the initial treatment.  相似文献   
8.
Investigators in the present study explored the effects of hyperbaric oxygen (HBO) therapy on distraction osteogenesis in a rabbit limb-lengthening model. HBO treatment was provided to participants in a small animal pressure chamber once a day during the latent period of distraction osteogenesis at 2.5 absolute atmospheres of pressure. Bone mineral density measurements were obtained through torsional testing. The control group received no HBO treatment. Animals were killed 8 wk postoperatively for biomechanical testing. There was a statistically significant increase in bone mineral density in the HBO group compared with that in the non-HBO group, but no statistically significant differences were observed between biomechanical parameters of the 2 groups. The investigators suggest that these results must be further studied through histologic examination to determine the stepwise effects of HBO during and after collagen synthesis.  相似文献   
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10.
Journal of Clinical Immunology - Immune responses to coronavirus disease 2019 (COVID-19) mRNA vaccines in primary antibody deficiencies (PADs) are largely unknown. We investigated antibody and CD4+...  相似文献   
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