Diabetes as a risk factor for periodontal disease—plausible mechanisms

The present narrative review examines the scientific evidence of the biological mechanisms that may link periodontitis and diabetes, as a source of comorbidity. Publications regarding periodontitis and diabetes, in human, animals, and in vitro were screened for their relevance. Periodontal microbiome studies indicate a possible association between altered glucose metabolism in prediabetes and diabetes and changes in the periodontal microbiome. Coinciding with this, hyperglycemia enhances expression of pathogen receptors, which enhance host response to the dysbiotic microbiome. Hyperglycemia also promotes pro-inflammatory response independently or via the advanced glycation end product/receptor for advanced glycation end product pathway. These processes excite cellular tissue destruction functions, which further enhance pro-inflammatory cytokines expression and alteration in the RANKL/osteoprotegerin ratio, promoting formation and activation of osteoclasts. The evidence supports the role of several pathogenic mechanisms in the path of true causal comorbidity between poorly controlled diabetes and periodontitis. However, further research is needed to better understand these mechanisms and to explore other mechanisms.     

Pre-eclampsia is associated with sleep-disordered breathing and endothelial dysfunction.

Pre-eclamptic toxaemia (PET) may be associated with both endothelial dysfunction (ED) and sleep-disordered breathing (SDB). It was hypothesised that females with PET would demonstrate both SDB and ED, and that a correlation between these two would suggest a potential causative association. A total of 17 females with PET and 25 matched females with uncomplicated pregnancy were studied. They underwent a nocturnal ambulatory sleep study (using Watch_PAT100) and noninvasive evaluation of endothelial function utilising the reactive hyperaemia test (using Endo_PAT 2000). A higher ratio of post- to pre-occlusion pulse-wave amplitude (endothelial function index (EFI)) indicated better endothelial function. Females with PET had a significantly higher respiratory disturbance index (RDI) and lower EFI than controls (18.4+/-8.4 versus 8.3+/-1.3.h(-1), and 1.5+/-0.1 versus 1.8+/-0.1, respectively). Blood pressure significantly correlated with RDI and with EFI. EFI tended to correlate with RDI. In conclusion, these results suggest that both sleep-disordered breathing and endothelial dysfunction are more likely to occur in females with pre-eclamptic toxaemia than in females with uncomplicated pregnancies. The current authors speculate that respiratory disturbances contribute to the functional abnormality of the blood vessels seen in females with pre-eclamptic toxaemia, although causality cannot be determined based on this study.     

Emergency orthodontic treatment after the traumatic intrusive luxation of maxillary incisors.

Treatment of traumatically intruded teeth is based largely on empirical clinical experience rather than on scientific data. The aim of this qualitative meta-analysis was to provide an evidence base to evaluate the orthodontic repositioning approach. In a MEDLINE search of the literature in English, 14 reported patients involving 22 teeth were found to have been treated by this modality. Additionally, 3 new patients, involving 9 intruded teeth and presented herein, were combined to form a total study sample of 17 subjects (7 girls, 10 boys, aged 8.9 +/- 1.2 years). Orthodontic extrusive forces were applied in the immediate posttrauma period (up to 3 months), with a variety of orthodontic appliances. Repositioning was achieved for 90.3% of the affected teeth but failed in 9.7% because of inflammatory resorption (2 teeth) or a misdiagnosis of root fracture (1 tooth). Early complications included loss of pulp vitality and external root resorption. All intruded teeth with closed root apices lost their vitality regardless of the degree of intrusion, whereas among those with incomplete apices, 45.5% that had been moderately intruded remained vital. External resorption was encountered in 54.8% of the teeth. Loss of marginal bone support was rarely encountered. Late complications included inflammatory root resorption in teeth with closed apices, in which endodontic treatment was not initially performed, and obliteration of the pulp tissue in teeth that remained vital. The results show that this method is superior to other treatment alternatives.     

Detecting pediatric autoimmune neuropsychiatric disorders associated with streptococcus in children with obsessive-compulsive disorder and tics.

BACKGROUND: A subgroup of children with obsessive-compulsive and tic disorders are proposed to have an infectious trigger. The purpose of this study was to investigate the relationship between group A streptococcal titers and symptom fluctuations in children with a clinical course resembling that described for pediatric autoimmune neuropsychiatric disorders associated with streptococcus. METHODS: Twenty-five children with obsessive-compulsive disorder and/or tic disorder were evaluated for neuropsychiatric severity and group A streptococcal antibody titers (streptolysin O, deoxyribonuclease B, and carbohydrate A) at 6-week intervals for > or = six consecutive evaluations (total visits=277). RESULTS: Children with large symptom fluctuations (n=15) were compared with children without dramatic fluctuations (n=10). Co-movements of obsessive-compulsive/tic severity and group A streptococcal antibodies were assessed. In subjects with large symptom changes, positive correlations were found between streptococcal titers and obsessive-compulsive severity rating changes (p=.0130). These subjects were also more likely to have elevated group A streptococcal titers during the majority of observations (p=.001). Tic symptom exacerbations occurred more often in the fall/winter months than spring/summer months (p=.03). CONCLUSIONS: Patients with marked obsessive-compulsive/tic symptom changes may be characterized by streptococcal titer elevations and exhibit evidence of seasonal tic exacerbations.     

Optimal use of electroconvulsive therapy: choosing a treatment schedule.

Choice of treatment schedule is an important component of the ongoing efforts to optimize electroconvulsive therapy (ECT) administration and thereby maximize therapeutic benefit while reducing cognitive adverse effects. Frequency of ECT administration (that is, the spacing between treatments) and the total number of treatments in a series are the two factors that define the ECT schedule. Available evidence supports the view that a schedule of twice weekly ECT with a total of six to eight treatments is an effective therapeutic regiment that potentially reduces cognitive morbidity associated with more frequent administration and a larger number of treatments. More frequent administration, however, may accelerate antidepressant response and may be indicated in cases in which rapidity of therapeutic effect is a significant clinical consideration. This consideration may be at the cost of greater cognitive impairment, which could be reduced by limiting the number of treatments administered. Aside from their clinical relevance, these issues have important implications for understanding the mechanisms of action of ECT.     

Isochronic transplantation of neonatal grafts in the visual cortex of cats: responsiveness,ocular dominance and specificity of cortical cells to visual stimulation

Summary The visual cortex of adult cats was studied physiologically following neonatal isochronic transplantation of grafts from areas 17,18, which were placed homotopically, in order to reveal their functional integration and thus possible repairing of damaged cortical neuronal circuits. Three homograft cats, in which transplantation was carried out between siblings (228 cortical cells) were compared to 4 animals receiving reimplanted autografts of the equivalent size (131 cells) as well as 3 animals with analogous sectioning of the visual cortex (162 cells) (pseudograft controls). The location of the boundaries between the transplant region and the host were determined using the Nissl's method for staining histological cross sections. Extracellular unit recording revealed typical waveform of the action potentials in the transplanted region and in the surrounding host tissue of all groups of cats. Visual responsiveness in the homograft cats was 17.5% in the transplanted region and 80.4% in the unoperated hemisphere; the corresponding results were 40.3% for the transplanted region and 82.2% for the unoperated hemisphere in the autografts and 23.1% and 73.4% in the pseudografts. The specificity of the cells to visual stimulation as expressed by their orientation and direction specificity, indicated preservation of these properties in the transplanted cats. While all responsive cells in the transplanted region of the homografts were orientation specific, their proportion was 60% in the autografts and 55.5% in the analogous region in the pseudograft controls. As to the direction specific cells, their performance in the grafted region of the grafted cats was even much higher than that of the pseudograft controls. The ocular dominance distribution of the cells showed preservation of binocularity in the transplanted region (90.0% binocular cells) of the homografts; it was however smaller in the equivalent region of the autografts (65.0%) and remarkably reduced (20.0%) in the pseudografts. It was concluded that despite the deafferentation induced during the transplantation procedure, a remarkable visual responsiveness was found in the transplanted region, indicating postoperative recovery. However, the cells there were mainly affected in their activity and less in their specificity to visual stimulation.     

Unknown syndrome in sibs: pili torti, growth delay, developmental delay, and mild neurological abnormalities.

We present male and female sibs of consanguineous parents with features including pili torti with unusual hair shaft electron microscopic (EM) findings, growth delay, developmental delay, and mild to moderate neurological abnormalities. The features of the cases presented here have not been noted in the previously reported clinical syndromes in which pili torti may be found.     

Adjunct endarterectomy of the left anterior descending coronary artery

During a three-year period, complete revascularization of diffusely diseased left anterior descending (LAD) coronary arteries was accomplished by extensive endarterectomy in conjunction with bypass grafting in 37 patients in whom conventional bypass was not feasible. This group constituted 7.0% of all patients undergoing nonemergency coronary revascularization during this period. The left internal mammary artery was used to bypass the endarterectomized LAD artery in 22 patients. There was 1 (2.7%) operative death and 1 perioperative myocardial infarction. At follow-up, which was 100% with a mean of 41.4 months, all endarterectomy patients were in New York Heart Association Functional Class I or II. Twenty-four endarterectomy patients underwent first-pass radionuclide angiographic stress testing 20 months after operation. Twenty patients (83%) had excellent postoperative exercise tolerance, achieving 5 to 7 mets on treadmill testing. Left ventricular functional reserve was preserved, as evidenced by an increase of global ejection fraction from 48 +/- 15% at rest to 59 +/- 18% (p less than 0.005) with exercise. A similar increase was measured in the proximal and distal anterior wall segmental ejection fractions. No difference in response to exercise was found between the internal mammary artery and the vein graft groups. Thus, complete revascularization of the diffusely diseased LAD artery can be accomplished by adjunct endarterectomy without added morbidity or mortality and with excellent functional results.