Simple and aneurysmal bone cyst: Aspects of jaw pseudocysts based on an experience of Brazilian pathology service during 53 years.

BACKGROUND: Jaw pseudocysts are benign osseous lesions of unclear etiology. Among these, the simple bone cyst (SBC) and aneurysmal bone cyst (ABC) are intriguing bone pathologies still rarely studied together. This retrospective study aimed to present the long-term case series of patients with jaw pseudocysts focusing on the clinical, radiographic, and transoperative aspects. MATERIAL AND METHODS: A retrospective case series of patients with SBC and ABC was performed. Clinical, radiographic, and transoperative aspects of both pseudocysts were reviewed from the histopathological archives of 20,469 cases between 1959-2012. All descriptive data were summarized. RESULTS: Of 354 (15.25%) bone pathologies, 54 cases of jaw pseudocysts were found, with 42 (11.86%) SBC and 12 (3.39%) ABC cases. For both lesions, most of the sample were young Caucasian women with an asymptomatic posterior mandible lesion with undetermined time of evolution and none trauma history. A unique radiolucent scalloped lesion presenting an empty cavity were also observed for both conditions. However, some atypical findings were found for SBC including: the expansion of bone cortical, tooth resorption, displacement of the mandibular canal, and recurrence. The absence of painful symptoms and the lack of classical blood-filled cavity were observed in some cases of ABC. CONCLUSIONS: The SBC and ABC are bone pathologies with few retrospective studies, no previous studies on the two conditions, varied nomenclature, and atypical aspects in some cases. Therefore, the knowledge of clinical, imaging, and transoperative features of such pseudocysts are clinically valuable as diagnosis hypothesis of radiolucent lesions of the jaws.

Systemic hypoxia and the depression of synaptic transmission in rat hippocampus after carotid artery occlusion.

The relationship between step reductions in inspired oxygen and the amplitude of evoked field excitatory postsynaptic potentials (fEPSPs) recorded from hippocampal CA1 neurons was examined in anaesthetized rats with a unilateral common carotid artery occlusion. The amplitudes of fEPSPs recorded from the hippocampus ipsilateral to the occlusion were significantly more depressed with hypoxia than were the fEPSPs recorded from the contralateral hippocampus. The adenosine A1-selective antagonist, 8-cyclopentyl-1,3-dimethylxanthine (8-CPT), blunted the hypoxic depression of the fEPSP. Tissue partial pressure of oxygen (Ptiss,O2) was measured in the ipsilateral and contralateral hippocampus using glass Clark-style microelectrodes. Ptiss,O2 fell to similar levels as a function of inspired oxygen in the ipsilateral and contralateral hippocampus, and in the ipsilateral hippocampus after administration of 8-CPT. Hippocampal blood flow (HBF) was measured using laser Doppler flowmetry. A decline in HBF was associated with systemic hypoxia in both hippocampi. HBF, as a function of inspired oxygen, fell significantly more in the ipsilateral than in the contralateral hippocampus. We conclude that endogenous adenosine acting at the neuronal A1 receptor plays a major role in the depression of synaptic transmission during hypoxic ischaemia. The greater susceptibility of the fEPSP in the ipsilateral hippocampus to systemic hypoxia cannot be explained entirely by differences in Ptiss,O2 or HBF between the two hemispheres.

Benzylidene analogs of anabaseine display partial agonist and antagonist properties at the mouse 5-hydroxytryptamine(3A) receptor.

The nicotinic receptor drug candidate, 3-(2,4-dimethoxybenzylidene)-anabaseine (also known as GTS-21; DMXBA), its hydroxy metabolites, and some related analogs were evaluated with the two-electrode voltage-clamp technique in mouse 5-hydroxytryptamine (5-HT)(3A) receptors expressed in Xenopus oocytes. Although DMXBA lacked partial agonist activity, its hydroxy-benzylidene metabolites and related analogs were partial agonists, displaying the following rank order of potency (EC(50)) and apparent efficacy: 5-HT, 0.9 +/- 0.06 microM (100% efficacy) > 3-(2-hydroxy,4-methoxybenzylidene)-anabaseine (2-OH-MBA), 2.0 +/- 0.3 microM (63% efficacy) > 3-(2,4-dihydroxybenzylidene)-anabaseine, 2.6 +/- 0.3 microM (63% efficacy) > 3-(2-methoxy,4-hydroxybenzylidene)-anabaseine, 17.2 +/- 1.0 microM (30% efficacy). To examine the influence of a benzylidene ring hydroxy substituent, the agonist actions of the three possible monohydroxy isomers were examined. The rank order of potency, based on EC(50) determinations, and apparent efficacy was: 3-(2-hydroxybenzylidene)-anabaseine, 20.3 +/- 2.6 microM (63% efficacy) > 3-(4-hydroxybenzylidene)-anabaseine, 32.3 +/- 5.9 microM (14% efficacy) > 3-(3-hydroxybenzylidene)-anabaseine (3-OH-BA) (no agonist activity). Both DMXBA and 3-OH-BA antagonized 5-HT-mediated currents, with IC(50) values of 15.7 +/- 0.9 and 27.5 +/- 4.7 microM, respectively. DMXBA demonstrated both competitive and noncompetitive forms of antagonism over the range of concentrations tested. These results suggest that a hydroxy substituent at the 2' position of the benzene ring is necessary and sufficient for partial agonist activity; substitution at the 4' position with a hydroxy or methoxy group further enhances agonist potency. Because 2-OH-MBA is a primary metabolite of DMXBA, it may contribute to the physiological, biochemical, and behavioral effects of the parent compound when administered in vivo.

Effects of forebrain microinjection of cholecystokinin on dopamine cell firing rate.

In anesthetized rats, midbrain dopamine (DA) neuronal firing rate was differentially sensitive to focal brain microinjection of cholecystokinin peptides (CCK-4 and CCK-8) and N-methyl-D-aspartate (NMDA) into nucleus accumbens, amygdala and prefrontal cortex. Whereas changes in DA neuronal firing rate were frequently observed in response to intra-amygdalar microinjection of CCK peptides, NMDA was most effective in eliciting changes in DA neuronal activity following intra-accumbal microinjection. Thus, stimulation of amygdalar CCK receptors and accumbal excitatory amino acid receptors may participate in the afferent regulation of midbrain DA neuronal function.

Overflow of dopamine and cholecystokinin in rat nucleus accumbens in response to acute drug administration.

Cholecystokinin octapeptide (CCK-8) coexists with dopamine (DA) in rat mesencephalic neurons that project to the nucleus accumbens. To obtain indices of corelease, microdialysis probes were placed in the posterior nucleus accumbens of anesthetized rats, which were then injected acutely (s.c.) with drugs that exert known effects on DA neuronal function. Microdialysis samples were assayed for DA and CCK-8 to determine the differential overflow of these cotransmitters in response to drug treatment. Haloperidol (0.5 mg/kg), d-amphetamine (1 mg/kg), and TCP (5 mg/kg) preferentially increased DA overflow, whereas morphine (5 mg/kg) elicited marked increases in the overflow of both DA and CCK-8. These results suggest that the release of accumbal DA and CCK-8 can be differentially regulated by drug treatment.

Mutation of putative phosphorylation sites in the 5-hydroxytryptamine3 receptor does not eliminate its modulation by ethanol.

The function of the 5-hydroxytryptamine3 (5-HT3) receptor is enhanced by ethanol, but the amino acid residue(s) that confers sensitivity to ethanol remains to be identified. Phosphorylation of the related GABA(A) receptor has been implicated in conferring its sensitivity to ethanol. In common with the GABA(A) receptor, the 5-HT3 receptor contains multiple consensus sites for protein kinases. To evaluate the possibility that phosphorylation of the 5-HT3 receptor underlies its ethanol sensitivity, we examined the ability of ethanol to enhance 5-HT-mediated currents in a mutant 5-HT3 receptor containing no intracellular serines, threonines, or tyrosines. Mutation of these 13 residues in the intracellular loops produced a modest leftward shift in the 5-HT concentration response curve, with the EC50's for 5-HT decreasing from 0.839 +/- 0.03 microM in the wild-type receptor to 0.713 +/- 0.03 microM in the mutant receptor. Cooperativity of the 5-HT binding sites was enhanced by the mutations, with Hill coefficients of 2.92 for the wild-type receptor and 3.74 for the mutant receptor, respectively. In oocytes expressing mutant receptors, ethanol (50 to 200 mM) enhanced the currents produced by low concentrations of 5-HT by approximately 5 to 45%, which was not statistically different from the potentiation produced by ethanol in wild-type receptors. These results suggest that ethanol enhancement of the 5-HT3 receptor function does not require receptor phosphorylation.

Money as a tool to extinguish conditioned responses to cocaine in addicts.

Classical conditioning principles offer a nondrug way to treat cocaine dependence. Eleven male subjects with the primary diagnosis of cocaine dependence were placed into one of two groups. The experimental group was asked to handle $500 cash in a mock budgetary task. The control group was asked to just imagine handling and budgeting the money. The subjects rated their craving-related feelings before and after each task. The experimental group showed significantly more craving after the money-handling task as compared to the control group, and the scores improved with time and as more tasks were completed. These data show that craving induced by handling cash is powerful and can be attenuated, at least on a short-term basis, using classical extinction procedures.

Effects of administration of cholecystokinin into the VTA on DA overflow in nucleus accumbens and amygdala of freely moving rats.

The carboxyterminal octapeptide of cholecystokinin (CCK-8) coexists with dopamine (DA) in mesolimbic neurons of the ventral tegmental area (VTA). In the present study, in vivo microdialysis in freely moving rats was used to assess the relative effects of sulfated CCK-8 (CCK-8S), unsulfated CCK-8 (CCK-8US) and CCK tetrapeptide (CCK-4), focally injected into the VTA, on DA overflow in two mesolimbic DA/CCK-8S terminal regions, the nucleus accumbens and the amygdala. Consistent with electrophysiological findings, microinjection of CCK-8S, but not CCK-8US or CCK-4, elicited increases in DA overflow in both terminal regions. In the absence of anatomical evidence of CCK-containing fibers in the VTA region, it seems reasonable to conclude that the modulation of terminal DA overflow by CCK-8S through actions at the somatodendritic region represents a form of autoregulation of these cells. Whereas CCK-8US and CCK-4 are preferential CCK-B receptor agonists, CCK-8S binds non-selectively to CCK-A and CCK-B receptors. Thus, these results implicate CCK-A receptors in the stimulatory effects of CCK-8S on VTA DA neurons.

Striatal extracellular dopamine in conscious vs. anesthetized rats: effects of chloral hydrate anesthetic on responses to drugs of different classes.

Many investigations using the microdialysis technique have been performed in anesthetized animals, both in this laboratory and elsewhere. Concern arises with this preparation that the anesthetic may compromise neuronal function, or that it may interact with test drugs affecting neurotransmitter overflow. In addition, in these studies the microdialysis probe typically is introduced into the brain on the day of testing, and data collection commences within an hour or two following probe insertion. It has been suggested that transmitter recovered in the perfusate probably represents leakage due to tissue damage as well as exocytotic release, and may not accurately reflect neuronal responses to the manipulations of interest. Such potential confounds present important implications for the interpretation of data from these studies. The present investigation examined the effects of chloral hydrate anesthetic on (1) basal dopamine (DA) overflow in the anterior striatum, and (2) DA responses to systemically delivered drugs of two different classes known to influence DA activity. Three putative indices of impulse-dependent release were measured: (a) the time course and stability of basal DA overflow over several hours; (b) sodium channel involvement by adding tetrodotoxin (TTX) to the artificial CSF; and (c) calcium channel involvement using magnesium (Mg) in a calcium-free perfusate. Basal DA levels became stable in both conscious and anesthetized preparations by the second hour after probe insertion. Levels of recovered DA overflow in the anterior striata of conscious rats were approximately double those in chloral hydrate-anesthetized rats. Consistent with other findings, this suggests a general depression of CNS function by chloral hydrate.(ABSTRACT TRUNCATED AT 250 WORDS)

Oral health knowledge and habits of senior elementary school students.

Despite improvements in children's dental health, and significant resource allocation to health education programs, few recent studies have investigated the associations of oral health knowledge, behaviors, and status. This study of 11-year-old children (N = 6,329) in northeastern Ontario used a supervised self-complete questionnaire and a clinical examination to gather baseline data on, and test associations of, caries and periodontal knowledge, self-reported oral health behaviors and source of knowledge, and oral health status. Results show the children had poor knowledge of caries preventive measures such as water fluoridation, dental sealants, and choice of snack foods. Periodontal knowledge was better, but children confused plaque and calculus. Respondents claimed good oral health habits, with 73 percent claiming to brush at least twice daily, 88 percent claiming to use toothpaste, 42 percent claim to floss at least twice weekly, and 84 percent claiming an annual dental visit. Children with the best knowledge claimed dentist and school as the sources. High knowledge was associated with good oral health habits (P less than .001) and low DMFT score (P less than .001). Good habits were not related to DMFT score (P = .1095). Logistic regression showed high knowledge was associated with English cultural status, urban school area, good habits, having a dental sealant, and attending a fluoride-rinse school (P less than .05). Findings suggest a need to reinforce caries preventive teaching, to investigate the effect of cultural status, dental experience, and residence status on oral health knowledge, and to further test the efficacy of different oral health education programs delivered by different sources.

Eosinophilic fasciitis associated with L-tryptophan ingestion.

A 62 year old woman taking L-tryptophan developed eosinophilic fasciitis shortly after starting an exercise class. She received prednisone without benefit but improved after azathioprine treatment was started and L-tryptophan was discontinued. As products containing L-tryptophan have recently been implicated in development of the eosinophilia-myalgia syndrome it is suggested that the use of L-tryptophan might have contributed to the development of eosinophilic fasciitis in this patient. Similarities with toxic oil syndrome are noted. Additional studies are warranted to determine the prevalence of L-tryptophan ingestion among patients diagnosed as having eosinophilic fasciitis.

Neurochemical, endocrine and immunological responses to stress in young and old Fischer 344 male rats.

Two experiments were performed. In the first, a 20 min conditioned emotional response (CER) paradigm was used to compare the neurochemical, endocrine and immunological responses to stress of 7- and 22-month-old Fischer 344 (F344) male rats. In the second, corticosterone levels 20 min following ether stress, and regional brain type I and II corticosterone receptor densities were examined using 7- and 17.5-month-old F344 male rats. Dopamine (DA) metabolism in old nonstressed rats was significantly reduced in the medial frontal cortex, neostriatum, nucleus accumbens and hypothalamus, but not in the amygdala. The CER procedure, nevertheless, increased medial frontal cortical, nucleus accumbens and amygdaloid DA turnover in both the young and old rats. The young and old nonstressed rats did not evidence differences in norepinephrine (NE) and serotonin (5-HT) concentrations. However, stress resulted in a decrease in medial frontal cortical 5-hydroxyindoleacetic acid (5-HIAA) and hypothalamic 5-HT levels in old but not in young animals. These observations suggest age-related differences in the response of central NE and 5-HT systems to stress. Ether and the CER procedure led to exaggerated corticosterone responses in the old rats (17.5 and 22 month, respectively). Hippocampal type I but not type II corticosterone receptors were decreased by 47% in the 17.5-month-old rats. Thus, age-related changes in hippocampal corticosterone receptor types do not occur in unison, and the exacerbated corticosterone response to stress precedes the reported down-regulation of hippocampal type II corticosterone receptors in aged rats. Age-related changes were not observed in the concentrations of corticosterone receptors in other brain regions, or in the prolactin response to stress. The old rats, however, evidenced a reduction in the availability of the renin substrate, angiotensinogen, and in stress-induced renin secretion. Immune function was impaired in the old nonstressed rats, and further compromised by exposure to the CER procedure. In comparison to the young control rats, the old nonstressed rats showed an increased percentage of splenic large granular lymphocytes, reduced splenic natural killer cytotoxicity, and impaired Con-A-stimulated splenic T lymphocyte proliferation. Reductions in T splenic cell proliferation and natural killer cytotoxicity were observed in the young rats subjected to the CER paradigm, but not to the same extent as in the old rats. These observations indicate that aging male F344 rats evidence major alterations in basal central monoamine, endocrine and immune functions, and an increased sensitivity of these systems to stress.

Feeding elicited by dynorphin (1-13) microinjections into the ventral tegmental area in rats.

Both the endogenous opioid peptide, dynorphin (1-13) (DYN), and morphine elicited dose-dependent feeding when microinjected into the ventral tegmental area of food-satiated rats. DYN was 50,000 times more potent than morphine in producing feeding. Whereas the ED50 for morphine was in the nanomole range, the ED50 for DYN was in the femtomole range. Administration of a narcotic antagonist attenuated DYN-elicited feeding. These data suggest a possible role for DYN in the VTA in opioid modulation of feeding behavior.

Influence of p-chloroamphetamine and methysergide on the escape deficits provoked by inescapable shock.

The effects of serotonergic manipulations on the escape interference engendered by exposure to inescapable shock were assessed. Consistent with the view that the behavioral interference was related to reductions of serotonin (5-HT), treatment with the 5-HT receptor blocker methysergide mimicked the effects of inescapable shock in that it increased escape latencies. Conversely, acute treatment with a moderate dose of the 5-HT releasing agent p-chloroamphetamine (PCA) effectively antagonized the escape interference ordinarily provoked by inescapable shock. The effects of PCA were behaviorally distinguishable from the previously observed effects of catecholamine stimulants. Whereas catecholamine stimulants applied prior to either inescapable shock or escape testing eliminated the interference, PCA antagonized the behavioral disruption only if it was administered before testing. It is suggested that catecholamine alterations may be fundamental in the provocation of the interference, whereas 5-HT variations may contribute to the expression of the behavioral disturbance.