Computed tomography evaluation of temporomandibular joint alterations in patients with class II division 1 subdivision malocclusions: condyle-fossa relationship.

Thirty persons with Class II Division 1 subdivision malocclusions, ranging in age from 12 years 8 months to 42 years, underwent computed tomography of the temporomandibular joints. The images obtained from sagittal slices were used to assess the depth of the mandibular fossa, the angulation of the posterior wall of the articular tubercle, the condyle-fossa relationship, and the concentric position of the condyles associated with this malocclusion. Paired Student t tests were applied, and Pearson product moment correlations (r) were determined after measurements on both Class I and Class II sides were obtained. No statistically significant asymmetries were found in the depth of the mandibular fossa, the angulation of the posterior wall of the articular tubercle, or the condyle-fossa relationship. However, a statistically significant (P <.05) anterior positioning of the condyles was observed.     

Antioxidant Activity of Limonene on Normal Murine Lymphocytes: Relation to H2O2 Modulation and Cell Proliferation

Abstract: Limonene is a monoterpene present in citrus fruit and is used as flavouring agents of foods. It was shown that monoterpenes possess antioxidant activity. Previously, it was demonstrated that limonene exerts anti‐proliferative action on a lymphoma cell line without modifying normal lymphocyte viability. H₂O₂ has a modulator role in cell proliferation. In the present study, the effect of limonene on normal lymphocytes proliferation and its relation with H₂O₂ level modulation was analysed, evaluating its effect on the activity of cell antioxidant enzymes, such as catalase, peroxidase and superoxide dismutase. Limonene exerted a biphasic effect on cell proliferation; the increase in cell proliferation was related to the decrease in H₂O₂ level by the increase in catalase and peroxidase activities. Moreover, limonene protected the cells to the oxidative stress induced by exogenous addition of H₂O₂. In view of these results, it is possible that limonene could protect normal lymphocytes from diseases related to oxidative stress, including cancer, but further research is necessary to establish the role of limonene as a potential antioxidant that can effectively protect lymphocytes from oxidative stress and mitochondrial dysfunction.     

Permeability of pure lipid bilayers to melatonin

Abstract: Melatonin, the chief hormone of the pineal gland, has been reported to interact with a variety of different cells. This ubiquitously acting hormone has been found to interact with protein receptors both at the cell membrane and in the nucleus. Moreover, melatonin was recently shown to be a very potent hydroxyl radical scavenger. The present work focuses on the interaction of melatonin with pure lipid bilayers. It is shown that melatonin can cross multilamellar lipid vesicles, which are used here as model systems for the lipid phase of biological membranes. Thus, the data prove that melatonin can easily pass through the cell membrane and bath every part of the cell, as previously suggested in the literature. Melatonin lipid association constant was calculated based on the change of the hormone fluorescence intensity due to its penetration into the hydrophobic lipid phase. Though melatonin was recently shown to be highly soluble in aqueous media, its lipid association constant is rather high, indicating that the biological action of the hormone is likely to be at the membrane level, either via its interaction with membrane receptors, and/or as a lipoperoxidation radical scavenger.     

Idiopathic membranous glomerulonephritis in Brazil

Summary: A survey of the medical records and renal biopsy reports of 41 patients with a diagnosis of membranous glomerulonephritis seen at the University Hospital, Faculty of Medicine of Ribeirão Preto, University of São Paulo was undertaken between 1961 and April 1992. Twenty-three of these patients were found to have idiopathic membranous glomerulonephritis (IMG) and 22 of them were treated with corticosteroids and/or immunosuppressants. Data for these 22 patients showed that the age at clinical presentation was 36.3± 17.5 years, white skin colour predominated (14 patients), and 15 were males; nephrotic syndrome was the clinical presentation in 20 patients and proteinuria was accidentally discovered in two patients. On the first hospital visit 11 patients presented proteinuria of up to 3 g/24 h and 16 presented serum creatinine below 1.5 mg/dL, and 14 developed renal hypertension during follow up. Clinicalmorphological correlation permitted us to conclude (in agreement with the literature) that advanced patient age, intensity of proteinuria, serum creatinine levels above 1.5 mg/dL on the occasion of the first hospital visit, and arterial hypertension are clinical-laboratory factors indicating a poor prognosis for IMG. More advanced staging of glomerular damage, presence of segmental mesangial sclerosis and tubulointerstitial involvement are microscopic factors indicating a poor prognosis for IMG.     

Alcohol stimulates the release of dopamine in the ventral pallidum but not in the globus pallidus: a dual-probe microdialysis study.

The mesoaccumbens dopamine system has been hypothesized to be a common neural substrate mediating the actions of various drugs of abuse, including ethanol. However, the involvement of the mesopallidal dopamine system has received very little attention. The present study examined the effects of intraperitoneal (IP) ethanol administration on the extracellular levels of dopamine in the ventral pallidum (VP) and globus pallidus (GP) of Wistar rats. Rats were bilaterally implanted with microdialysis probes aimed at the VP and GP or nucleus accumbens (NAc) and dorsal striatum (dSTR). During microdialysis testing, rats with probes located in the VP and GP were injected IP with sterile saline or 15% (v/v) ethanol in saline at doses of 0.75, 1.5, or 2.25 g/kg. Rats with NAc and dSTR probes were injected with saline or 2.25 g/kg ethanol. The IP administration of 1.5 and 2.25 g/kg ethanol significantly (p <0.05) elevated the extracellular levels of dopamine in the VP (maximal increase: 136 and 182% of baseline, respectively) but not in the GP. No effects on extracellular dopamine levels were observed following the IP injections of 0.75 g/kg ethanol or saline. The IP administration of 2.25 g/kg ethanol significantly (p <0.05) elevated the extracellular levels of dopamine in the NAc (maximal increase: 198% of baseline) and dSTR (maximal increase: 155% of baseline). Analysis of the effects of 2.25 g/kg ethanol on dopamine release revealed greater increases in the VP, NAc, and dSTR compared to the GP. The data suggest that the mesopallidal, mesoaccumbens, and nigrostriatal dopamine systems are more sensitive to the effects of ethanol than the nigropallidal dopamine system.     

Comparative study of the effect of a tube drain in impacted lower third molar surgery.

PURPOSE: Postoperative variables such as pain, swelling, and trismus after surgery of the impacted lower third molars are the main concerns of dental clinicians and surgeons. Many authors claim that the use of a drain could help control these variables. The purpose of this study was to evaluate the effect of the use of a tube drain in impacted lower third molar surgery. MATERIALS AND METHODS: Fifty-three patients of both genders with bilateral impacted lower third molars comprised our comparative study. The patients were divided into 2 groups: in the first the suture procedure was accomplished using a drain, and in the second the suture procedure was accomplished without a drain. The postoperative pain, swelling, and trismus were evaluated at 24 hours, 72 hours, 7 days, and 15 days. RESULTS: In the group in which the drain was used, the control of the swelling variable was statistically significant at 24 and 72 hours (P <.001) in comparison with the group in which the drain was not used. However, pain and trismus were not statistically significant at the evaluation period. CONCLUSION: The use of the drain helps to control swelling. However, it had no effect on pain or trismus.     

Assessment of enamel hypoplasia in autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy (APECED)

The features of enamel hypoplasia in a small group of patients with autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy (APECED) are described. Using a recently developed method, the authors evaluated quantitatively the amount of defect in each tooth by measuring the width of the hypoplastic lesions and dividing the value by the crown height. They then assessed the degree of damage in each tooth type (from central incisors to second premolars) and patient. Canines were the most severely affected among maxillary and mandibular teeth, but all tooth types were involved. Analysing both the differences between patients and their age at the beginning of the defect, the authors observe that hypoparathyroidism is not responsible for the onset of enamel hypoplasia in APECED, although it may contribute to the damage.