Basal levels of DNA damage detected by micronuclei and comet assays in untreated breast cancer patients and healthy women

Breast cancer is the second most frequent type of cancer worldwide and is the most common malignant disease among women. Risk factors for breast cancer include early menarche, late menopause, hormonal therapies, exposure to environmental pollutants, smoking and alcohol use. However, increased or prolonged exposure to estrogen is the most important risk factor. It has been suggested that accumulation of DNA damage may contribute to breast carcinogenesis. Epidemiological studies suggest that cytogenetic biomarkers such as micronuclei in peripheral blood lymphocytes may predict cancer risk because they indicate genomic instability in target tissues. The objective of the present study was to evaluate the frequencies of micronuclei and the extent of DNA damage detected by comet assay in peripheral blood lymphocytes of untreated breast cancer patients and healthy women. The study was conducted using peripheral blood lymphocytes from 45 women diagnosed for Ductal ""in situ"" or invasive breast carcinoma and 85 healthy control women. Micronuclei and comet assays were performed to detect spontaneous DNA damage. The results showed that micronuclei frequencies and tail intensity, detected by comet assay, were significantly higher in the breast cancer group than in controls. The levels of DNA damage were similar in smokers and non-smokers, and aging did not influence the frequencies of micronuclei or tail intensity values observed in either group. In conclusion, the present work demonstrates higher levels of DNA damage in untreated breast cancer patients than in healthy women.

Chronic administration of harmine elicits antidepressant-like effects and increases BDNF levels in rat hippocampus

A growing body of evidence has pointed to the beta-carboline harmine as a potential therapeutic target for the treatment of major depression. The present study was aimed to evaluate behavioural and molecular effects of the chronic treatment with harmine and imipramine in rats. To this aim, rats were treated for 14 days once a day with harmine (5, 10 and 15 mg/kg) and imipramine (10, 20 and 30 mg/kg) and then subjected to the forced swimming and open-field tests. Harmine and imipramine, at all doses tested, reduced immobility time of rats compared with the saline group. Imipramine increased the swimming time at 20 and 30 mg/kg and harmine increased swimming time at all doses. The climbing time increased in rats treated with imipramine (10 and 30 mg/kg) and harmine (5 and 10 mg/kg), without affecting spontaneous locomotor activity. Brain-derived neurotrophic factor (BDNF) hippocampal levels were assessed in imipramine and harmine-treated rats by ELISA sandwich assay. Interestingly, chronic administration of harmine at the higher doses (10 and 15 mg/kg), but not imipramine, increased BDNF protein levels in rat hippocampus. Finally, these findings further support the hypothesis that harmine could bring about behavior and molecular effects, similar to antidepressants drugs.

Electrophysiologic Activity of the Vestibular Fold

Objectives: To assess the vestibular fold muscle after cordectomy and laryngeal reconstruction, the pattern of motor unit recruitment during sound emission, and the morphologic characteristics of motor unit action potentials. Design: Prospective analysis. Setting: Tertiary academic hospital. Patients: We evaluated 11 men (mean age, 65.7 years; age range, 53-82 years) who underwent laryngofissure, cordectomy, and laryngeal reconstruction with a vestibular fold flap. Interventions: Laryngeal electromyography with the insertion of a needle electrode for the assessment of the electrophysiologic activity of thyroartenoid muscle fibers and of the cricothyroid muscle on the operated on and nonoperated on sides. The thyroarytenoid muscle was evaluated by introducing a needle electrode through the thyroid cartilage and the cricothyroid membrane. Main Outcome Measures: Activities of needle insertion, spontaneous muscle activity during rest, and pattern of motor unit recruitment. Results: Seven patients (64%) had vestibular fold muscle fiber, all of whom showed motor unit recruitment in response to sound emission. No neurogenic muscle injuries were observed except in 1 patient with evidence of chronic injury. Conclusion: After cordectomy and laryngeal reconstruction, thyroarytenoid muscle fibers are present in the vestibular fold, with motor unit recruitment during sound emission.

Rubella Vaccination of Unknowingly Pregnant Women: The Sao Paulo Experience, 2001

Background. Rubella vaccination is contraindicated during pregnancy. During mass immunization of women of childbearing age against rubella, women unknowingly pregnant may be vaccinated. To evaluate the effects of rubella vaccination during pregnancy, the Brazilian state of Sao Paulo conducted a follow-up study of pregnant women vaccinated during a rubella campaign in 2001. Methods. Women vaccinated during pregnancy were reported to a national surveillance system. In the state of Sao Paulo, follow-up of vaccinated women included household interviews. Serum samples from vaccinated women were tested for antirubella antibodies to classify susceptibility to rubella infection. Children born to susceptible mothers were tested for evidence of congenital rubella infection and evaluated for signs of congenital rubella syndrome. Results. The Sao Paulo State Health Department received 6473 notifications of women vaccinated during pregnancy. Serology performed for 5580 women identified 811 (15%) that were previously susceptible. Incidence of spontaneous abortion or stillbirth among previously susceptible vaccinated women was similar to women with prior immunity. Twenty-seven (4.7%) of 580 newborns tested had evidence of congenital rubella infection; none had congenital rubella syndrome. Conclusions. Mass rubella vaccination of women of childbearing age was not associated with adverse birth outcomes or congenital rubella syndrome among children born to women vaccinated during pregnancy.

The effect of ovariectomy on cardiac autonomic control in rats submitted to aerobic physical training

We have investigated the ovariectomy effects on the cardiovascular autonomic adaptations induced by aerobic physical training and the role played by nitric oxide (NO). Female Wistar rats (n =70) were divided into five groups: Sedentary Sham (SS): Trained Sham (TS); Trained Hypertensive Sham treated with N(C)-nitro-L-arginine methyl ester (L-NAME) (THS): Trained Ovariectomized (TO); and Trained Hypertensive Ovariectomized treated with L-NAME (THO). Trained groups were submitted to a physical training during 10 weeks. The cardiovascular autonomic control was investigated in all groups using different approaches: 1) pharmacological evaluation of autonomic tonus with methylatropine and propranolol; 2) analysis of heart rate (HR) and systolic arterial pressure (AP) variability; 3) spontaneous baroreflex sensitivity (BRS) evaluation. Hypertension was observed in THS and THO groups. Pharmacological analysis showed that TS group had increased predominance of autonomic vagal tonus compared to SS group. HR and intrinsic HR were found to be reduced in all trained animals. TS group, compared to other groups, showed a reduction in LF oscillations (LF=0.2-0.75 Hz) of pulse interval in both absolute and normalized units as well as an increase in HF oscillations (HF=0.75-2.50 Hz) in normalized unit. FIRS analysis showed that alpha-index was different between all groups. TS group presented the greatest value, followed by the TO, SS. THO and THS groups. Ovariectomy has negative effects on cardiac autonomic modulation in trained rats, which is characterized by an increase in the sympathetic autonomic modulation. These negative effects suggest NO deficiency. In contrast, the ovariectomy seems to have no effect on AP variability. (C) 2008 Elsevier B.V. All rights reserved.

Inflammatory mediators involved in the nociceptive and oedematogenic responses induced by Tityus serrulatus scorpion venom injected into rat paws.

The present study investigated the role of kinins, prostaglandins (PGs) and nitric oxide (NO) in mechanical hypernociception, Spontaneous nociception and paw oedema after intraplantar (ipl) injection of Tityus serrulatus venom (Tsv) in male Wistar rats. Tsv was ipl-injected in doses of 0.01-10 mu g/paw. Pre-treatment (30 min prior) with DALBK (100 nmol/paw) and icatibant (10 nmol/paw), B1 and B2 selective kinin receptor antagonists, L-NAME (50 mg/kg, i.p., a non-selective nitric oxide synthase inhibitor) or celecoxib, selective COX-2 inhibitor, was given 1 h prior per os (5 mg/kg, p.o.), significantly reduced the hypernociceptive response (Von Frey method), the spontaneous nociception (determined by counting the number of flinches) and paw oedema (plethysmometer method) induced by Tsv at doses of 1.0 and 10 mu g/paw for both nociceptive and oedematogenic responses, respectively. Nevertheless, indomethacin (5 mg/kg, i.p.. 30 min prior) was ineffective in altering all of these events. The results of the present study show that Tsv, injected ipl into the rat paw, causes a dose-dependent paw oedema, mechanical hypernociception and flinches (a characteristic biphasic response) in which kinins and NO are substantially involved. Although celecoxib was effective against the oedema and pain caused by Tsv, COX-2 does not seem to be involved in the inflammatory response caused by Tsv. (C) 2008 Elsevier Ltd. All rights reserved.

Perinatal outcome of fetal atrioventricular block - One-hundred-sixteen cases from a single institution

Background-Fetal atrioventricular (AV) block is an uncommon lesion with significant mortality. Because of the rarity of this disorder, the natural course, extensive evaluation of untreated fetuses, and late follow-up remain unclear. Methods and Results-Of the 116 consecutive cases of fetal AV block studied from 1988 to 2006, only 1 was terminated, and 75% were live births. Fifty-nine cases of AV block were associated with major structural heart disease, mainly left atrial isomerism (n = 40), with only 26% of neonatal survivors. Of the 57 fetuses with normal cardiac anatomy, 41 (72%) were positive for maternal antinuclear antibodies, and 32 of these seropositive mothers did not receive any treatment. This untreated group had live-birth and 1-year infant survival rates of 93% and 90%, respectively. Five fetuses from seronegative mothers showed regression to sinus rhythm during pregnancy. The presence of major structural heart disease, hydrops, an atrial rate <= 120 bpm, and a ventricular rate <= 55 bpm were identified as risk factors for mortality. Logistic regression analysis of the whole group showed that the presence of structural heart disease was the only independent predictor of death (P < 0.001). Conclusions-This long-term study confirms that fetal AV block has a poor outcome when associated with structural heart disease and that spontaneous regression of AV block is possible in seronegative forms. The survival rate of >90% of our untreated patients with isolated forms of AV block raises concerns about any decision to intervene with immunosuppressive agents.

Tissue diffusion and retention of metalloproteinases in ascending aortic aneurysms and dissections

Histopathological alterations in human aneurysms and dissections of the thoracic ascending aorta include areas of mucoid degeneration within the medial layer, colocalized with areas of cell disappearance and disruption of extracellular matrix elastic and collagen fibers. We studied the presence of matrix metalloproteinases in relation to their capacity to diffuse through the tissue or to be retained in areas of mucoid degeneration in aneurysms and dissections of the ascending aorta. Ascending aortas from 9 controls, 33 patients with aneurysms, and 14 with acute dissections, all collected at surgery, were analyzed. The morphological aspect was similar whatever the etiology or phenotypic expression of the pathological aortas, involving areas of extracellular matrix breakdown and cell rarefaction associated with mucoid degeneration. Release of proMMP-2, constitutively expressed by smooth muscle cells, was not different between controls and aneurysmal aortas, whereas the aneurysmal aortas released more of the active form. Release of pro and active MMP-9 was also similar between controls and aneurysmal aortas. Immunohistochemical staining of MMP-2 and MMP-9 was weak in both control and pathological aortas. In contrast, released MMP-7 (matrilysin) and MMP-3 (stromelysin-1) could not be detected in conditioned media but were present in tissue extracts with no detectable quantitative difference between controls and pathological aortas. Immunohistochemical staining of MMP-7 and MMP-3 revealed their retention in areas of mucoid degeneration, and semiquantitative evaluation of immunostaining showed more MMP-7 in pathological aortas than in controls. In conclusion, areas of mucoid degeneration, the hallmark of aneurysms, and dissections of thoracic ascending aortas, whatever their etiology, are not inert and can retain specific proteases. (c) 2009 Elsevier Inc. All rights reserved.

Antitumoural effect of an L-amino acid oxidase isolated from Bothrops jararaca snake venom

An L-amino acid oxidase (BjarLAAO-I) from Bothrops jararaca snake venom was highly purified using a stepwise sequential chromatography on Sephadex G-75, Benzamidine Sepharose and Phenyl Sepharose. Purified BjarLAAO-I showed a molecular weight around 60,000 under reducing conditions and about 125,000 in the native form, when analysed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and gel filtration, respectively. BjarLAAO-I is a homodimeric acidic glycoprotein, pI similar to 5.0, and N-terminal sequence showing close structural homology with other snake venom LAAOs. The purified enzyme catalysed the oxidative deamination of L-amino acids, the most specific substrate being L-Phe. Five amino acids, L-Ser, L-Pro, L-Gly, L-Thr and L-Cys were not oxidized, clearly indicating a significant specificity. BjarLAAO-I significantly inhibited Ehrlich ascites tumour growth and induced an influx of polymorphonuclear cells, as well as spontaneous liberation of H(2)O(2) from peritoneal macrophages. Later, BjarLAAO-I induced mononuclear influx and peritoneal macrophage spreading. Animals treated with BjarLAAO-I showed higher survival time.

Distinct tumor suppressor mechanisms evolve in rodent species that differ in size and lifespan

Large, long-lived species experience more lifetime cell divisions and hence a greater risk of spontaneous tumor formation than smaller, short-lived species. Large, long-lived species are thus expected to evolve more elaborate tumor suppressor systems. In previous work, we showed that telomerase activity coevolves with body mass, but not lifespan, in rodents: telomerase activity is repressed in the somatic tissues of large rodent species but remains active in small ones. Without telomerase activity, the telomeres of replicating cells become progressively shorter until, at some critical length, cells stop dividing. Our findings therefore suggested that repression of telomerase activity mitigates the increased risk of cancer in larger-bodied species but not necessarily longer-lived ones. These findings imply that other tumor suppressor mechanisms must mitigate increased cancer risk in long-lived species. Here, we examined the proliferation of fibroblasts from 15 rodent species with diverse body sizes and lifespans. We show that, consistent with repressed telomerase activity, fibroblasts from large rodents undergo replicative senescence accompanied by telomere shortening and overexpression of p16(Ink4a) and p21(Cip1/Waf1) cycline-dependent kinase inhibitors. Interestingly, small rodents with different lifespans show a striking difference: cells from small shorter-lived species display continuous rapid proliferation, whereas cells from small long-lived species display continuous slow proliferation. We hypothesize that cells of small long-lived rodents, lacking replicative senescence, have evolved alternative tumor-suppressor mechanisms that prevent inappropriate cell division in vivo and slow cell growth in vitro. Thus, large-bodied species and small but long-lived species have evolved distinct tumor suppressor mechanisms.

Management of a permanent tooth after trauma to deciduous predecessor: an evaluation by cone-beam computed tomography

Impaction of permanent teeth represents a clinical challenge with regard to diagnosis, treatment plan, and prognosis. There is a close relationship between deciduous teeth and permanent teeth germ, and any injury in the deciduous dentition may influence the permanent teeth eruption. The extent of the damage caused to the permanent teeth germ depends on the patient age at the time of injury, type of trauma, severity, and direction of the impact. Conventional radiographic images are frequently used for diagnosis; however, recent developments in three-dimensional (3D) imaging systems have enabled dentistry to visualize structural changes effectively, with better contrast and more details, close to the reality. The cone-beam computed tomography (CBCT) has been used in the diagnosis and treatment plan of these impacted teeth. The purpose of the present case report is to describe a successful conservative management of a retained permanent maxillary lateral incisor with delayed root development after a trauma through the deciduous predecessor in a 9 year-old patient. After clinical and radiographic examination, a CBCT examination of the maxilla was requested to complement the diagnosis, providing an accurate 3D position of the retained tooth and its relationship to adjacent structures. The proposed treatment plan was the surgical exposure and orthodontic traction of the retained tooth. The lateral incisor spontaneously erupted after 6 months. Therefore, this case report suggests that permanent teeth with incomplete root formation have a great potential for spontaneous eruption because no tooth malposition or mechanical obstacles are observed.

Nitric oxide synthase inhibitors improve prepulse inhibition responses of Wistar rats

Introduction: Cognitive and attentional deficits in schizophrenia include impairment of the sensorimotor filter as measured by prepulse inhibition (PPI). In this way, the study of animals that naturally present low PPI responses could be a useful approach for screening new antipsychotic drugs. Several pieces of evidence suggest that dopamine and nitric oxide (NO) can modulate PPI but their role in those animals is unknown. Objectives: The aim of this study was to investigate the role of dopamine and NO in Wistar rats with naturally low PPI response. Methods: Male Wistar rats with low PPI responses received an i.p. injection of the antipsychotics haloperidol (0.1, 0.3 or 1 mg/kg) or clozapine (0.5, 1.5 or 5 mg/kg), the anxiolytic diazepam (1 or 3 mg/kg) or the NO synthase (NOS) inhibitors, N(G)- nitro-L-arginine (L-NOARG; 40 mg/kg, acutely or sub-chronically) or 7-Nitroindazole (7-NI; 3, 10 or 30 mg/kg). All animals were submitted to the PPI test 1 h after injection. Striatal and cortical dopamine, DOPAC, and noradrenaline levels of rats with low PPI responses were compared to rats with normal PPI responses. Results: We found increased levels of catecholamines on the striatum and prefrontal cortex of Wistar rats with low PPI. In these animals, both antipsychotics, typical and atypical, and NOS inhibitors significantly increased PPI. Conclusion: Taken together, our findings suggest that the low PPI phenotype may be driven by an over-active catecholamine system. Additionally, our results corroborate the hypothesis of dopamine and NO interaction on PPI modulation and suggest that Wistar rats with low PPI may represent an interesting non-pharmacological model to evaluate new potential antipsychotics. (C) 2010 Elsevier B.V. All rights reserved.

GABAergic antagonist blocks the reduction of tonic immobility behavior induced by activation of 5-HT(2) receptors in the basolateral nucleus of the amygdala in guinea pigs

Tonic immobility (TI) is a temporary state of profound motor inhibition induced by situations that generate intense fear, with the objective of protecting an animal from attacks by predators. A preliminary study by our group demonstrated that microinjection into the basolateral nucleus of the amygdala (BLA) of an agonist to 5-HT(1A) and 5-HT(2) receptors promoted a decrease in TI duration. In the current study, the effects of GABAergic stimulation of the BLA and the possible interaction between GABA(A) and 5-HT(2) receptors on TI modulation were investigated. Observation revealed that GABAergic agonist muscimol (0.26 nmol) reduced the duration of TI episodes, while microinjection of the GABAergic antagonist bicuculline (1 nmol) increased TI duration. Additionally, microinjection of 5-HT(2) agonist receptors (alpha-methyl-5-HT, 0.32 nmol) into the BLA decreased TI duration, an effect reversed by pretreatment with bicuculline (at the dose that had no effect per se, 0.2 nmol). Moreover, the activation of GABA(A) and 5-HT(2) receptors in the BLA did not alter the spontaneous motor activity in the open field test. These experiments demonstrated that the activation of GABA(A) and 5-HT(2) receptors of the BLA possibly produce a reduction in unconditioned fear that decreases the TI duration in guinea pigs, but this is not due to increased spontaneous motor activity, which could affect a TI episode nonspecifically. Furthermore, these results suggest an interaction between GABAergic and serotoninergic mechanisms mediated by GABA(A) and 5-HT(2) receptors. In addition, the GABAergic circuit of the BLA presents a tonic inhibitory influence on TI duration. (C) 2009 Elsevier Inc. All rights reserved.