Different effects of whitening treatment on natural teeth and teeth treated with Icon resin: an experimental study in vitro.

BACKGROUND: It is quite common for white spots to develop on a tooth, due sometimes to a defective formation of the enamel layer, and sometimes to patches of demineralisation as a result of poor oral hygiene during orthodontic treatment with fixed braces. ICON DMG is currently the only noninvasive treatment for white spots. After a preliminary etching, it infiltrates the enamel, filling the spaces between the prisms with a resinous material that has a refraction coefficient very similar to that of healthy tooth enamel. The aim of this study was to test the efficacy of professional whitening procedures on teeth previously treated with ICON. The study hypothesis was that infiltration with ICON resin creates a barrier capable of preventing the bleaching action of the whitening agent. MATERIALS: White spots were artificially created on one half of the vestibular surface of 12 human teeth, while the other half was protected with a composite adhesive. The white spots were infiltrated with ICON and the protective adhesive was subsequently removed. A professional teeth whitening procedure was then completed on both halves of the teeth. A statistical analysis was performed to compare spectrophotometric recordings obtained before and after the ICON infiltration and teeth whitening procedures. CONCLUSION: The whitening procedure modified the colour of the teeth on the half not infiltrated with ICON (p<0.05), but there was no statistically significant change in colour on the half infiltrated with ICON. The presence of the ICON resin seems to act as a partial barrier to the action of the whitening agent.

Metaphylactic effect of minerals on the immune response, biochemical variables and antioxidant status of newborn calves.

The aim of this study was to evaluate whether injectable zinc and copper affect host immune responses and antioxidant status of newborn calves. For this study, 19 newborn calves were divided into two groups. The control group consisted of 10 animals; and the treated group consisted of nine animals that received copper edetate (Cu-ed) and zinc edetate (Zn-ed) subcutaneously at the first day of life at doses of 0.3 mg/kg and 1.0 mg/kg respectively. Blood and faecal samples were collected for laboratory analyses (seric biochemistry, proteinogram, antioxidant enzymes and parasitological examination) on days 10, 20 and 30 after birth. On day 10, treated animals showed increased levels of total proteins, as well as increased globulin levels compared to the control group, a finding probably related to the increase in ceruloplasmin and IgG heavy chain. Thirty days after mineral metaphylactic administration, IgG light chain and acid glycoprotein levels significantly increased in treated animals (p < .05). There were no significant differences between groups regarding the biochemical analyses (triglycerides, cholesterol, glucose and urea). On the other hand, the superoxide dismutase and catalase activities increased on day 10 after treatment. In the control group, eight animals showed severe diarrhoea and one died 8 days after birth. Two animals from this group showed mild diarrhoea. Only three treated animals had severe diarrhoea, and six showed signs of mild diarrhoea. All animals that showed severe diarrhoea (control = 8; treated = 3) had hyperthermia (over 39.5°C), and therefore, antibiotic therapy was administered (sulfadiazine and trimethoprim) for five consecutive days. In summary, Zn-ed and Cu-ed decreased the frequency and intensity of diarrhoea, modulated superoxide dismutase (SOD) and catalase (CAT) enzymes and also heightened the immune responsiveness of newborn calves, suggesting a new approach to improve cattle performance and minimize the occurrence of diarrhoea.

Surgery beyond the visible light spectrum: theoretical and applied methods for localization of the male urethra during transanal total mesorectal excision.

The risk of urethral injury during transanal total mesorectal excision (taTME) is delineated, and potential risk factors for iatrogenic transection are reviewed. A variety of applied and theoretical techniques can be used by surgeons to diminish the risk of injury in males undergoing this operation. Many of the approaches utilize non-optic media and wavelengths beyond the visible light spectrum which can enhance the surgeon's frame of reference. The aim of the present study was to assess the techniques and theoretical approaches to urethral localization during taTME. Future directions in surgical imaging are also discussed, including the use of organic dyes, quantum dots, and carbon nanotubes; collectively, technology that could someday provide surgeons with an ability to identify anatomic structures prone to injury.

In vitro repellent effect of tea tree (Melaleuca alternifolia) and andiroba (Carapa guianensis) oils on Haemotobia irritans and Chrysomya megacephala flies.

This study aimed to evaluate the repellent effect of tea tree (Melaleuca alternifolia) and andiroba (Carapa guianensis) essential oils on two species of flies (Haemotobia irritans and Chrysomya megacephala). For the in vitro studies, free-living adult flies were captured and reared in the laboratory. To verify the repellency effect, an apparatus was constructed where H. irritans and C. megacephala were exposed to andiroba and tea tree oils (5.0%), as well as to a known repellent (citronella, 5.0%) to validate the test. The study demonstrated that all three oils used showed in vitro repellent effect against both species of flies. It is possible to conclude that the essential oils (tea tree and andiroba) have repellent effect on these species of flies used in this study.

Transmission of a multidrug-resistant HIV-! from an accupational exposure, in São Paulo, Brazil

We documented the first transmission of a multidrug-resistant HIV from an occupational exposure in Sao Paulo, Brazil, albeit with antiretroviral prophylaxis instituted within 1 h after the accident. A 27-year-old female healthcare worker (HCW) sustained an index finger needle stick injury with a 20-gauge needle while puncturing the forearm of an HIV-infected patient. The putative source (index) patient was a 44-year-old homeless female, on irregular use of zidovudine (AZT), lamivudine (3TC) and ritonavir boosted lopinavir(LPV/r). She was hepatitis C virus (HCV) coinfected and had been prescribed different regimens including nucleos(t)ide reverse transcriptase inhibitors (NRTI), non-nucleos(t)ide reverse transcriptase inhibitors (NNRTI) or protease inhibitors since 2011. Around the time of the accident, she had a HIV viral load of 4.56 log10, HCV viral load of 5.9 log10 (Abbott Real Time HIV and HCV, USA) and CD4+ cell count (BD Biosciences FACSCalibur Flow Cytometer, USA) of 143 cells/µl. After the HCW tested negative by rapid test, AZT/3TC/LPV/r was instituted, as suggested by current guidelines [1,2], within 1 h of the accident.

Omega-3 prevents behavior response and brain oxidative damage in the ketamine model of schizophrenia.

Supplementation with omega-3 has been identified as an adjunctive alternative for the treatment of psychiatric disorders, in order to minimize symptoms. Considering the lack of understanding concerning the pathophysiology of schizophrenia, the present study hypothesized that omega 3 prevents the onset of symptoms similar to schizophrenia in young Wistar rats submitted to ketamine treatment. Moreover, the role of oxidative stress in this model was assessed. Omega-3 (0.8g/kg) or vehicle was given by orogastric gavage once daily. Both treatments were performed during 21days, starting at the 30th day of life in young rats. After 14days of treatment with omega-3 or vehicle, a concomitant treatment with saline or ketamine (25mg/kg ip daily) was started and maintained until the last day of the experiment. We evaluated the pre-pulse inhibition of the startle reflex, activity of antioxidant systems and damage to proteins and lipids. Our results demonstrate that supplementation of omega-3 prevented: decreased inhibition of startle reflex, damage to lipids in the hippocampus and striatum and damage to proteins in the prefrontal cortex. Furthermore, these changes are associated with decreased GPx in brain tissues evaluated. Together, our results suggest the prophylactic role of omega-3 against the outcome of symptoms associated with schizophrenia.

Effect of maternal deprivation on acetylcholinesterase activity and behavioral changes on the ketamine-induced animal model of schizophrenia.

Maternal deprivation has been associated with physiological and developmental changes that may be related to an increased risk for childhood and adult neuropsychiatric diseases. A growing number of studies demonstrated the importance of childhood experiences in the development of psychosis and schizophrenia in adulthood. Therefore, the present study investigated different behavior responses in rats following maternal deprivation and/or ketamine treatment in adulthood. Male rats were subjected to maternal deprivation for 180 min from postnatal day-01 to postnatal day-10. We evaluated locomotor activity, avoidance task and social interaction of adult male rats deprived or not deprived that were administered with saline or acute subanesthetic doses of ketamine (5, 15 and 25 mg/kg, i.p.). Our results show that only ketamine (25 mg/kg, i.p.) treatment in the adult rats lead to hyperlocomotion but not ketamine (5 and 15 mg/kg) and maternal deprivation alone. However, maternally deprived rats treated with ketamine (5 mg/kg) induced hyperlocomotion. Additionally, ketamine (25 mg/kg) and maternal deprivation alone induced cognitive deficit in the avoidance task. Rats deprived of and treated with ketamine (5, 15 and 25 mg/kg) also lead to memory deficit. Moreover, ketamine (25 mg/kg) and maternal deprivation alone increased latency to start social behavior. However, ketamine (5 mg/kg) and maternal deprivation lead to an increase of latency to start social behavior. Biochemistry data showed that all doses of ketamine and ketamine plus maternal deprivation increased the acetylcholinesterase (AChE) activity in the prefrontal cortex, hippocampus and striatum. The major doses of ketamine associated with maternal deprivation induced a major increase of AChE activity. Together, our results suggest that animals subjected to maternal deprivation had an increased risk for schizophrenia-like behavior and cholinergic alteration.

Developmental origins of health and disease: experimental and human evidence of fetal programming for metabolic syndrome.

The concept of developmental origins of health and disease has been defined as the process through which the environment encountered before birth, or in infancy, shapes the long-term control of tissue physiology and homeostasis. The evidence for programming derives from a large number of experimental and epidemiological observations. Several nutritional interventions during diverse phases of pregnancy and lactation in rodents are associated with fetal and neonatal programming for metabolic syndrome. In this paper, recent experimental models and human epidemiological studies providing evidence for the fetal programming associated with the development of metabolic syndrome and related diseases are revisited.