In-Office dental bleaching efficacy assessment in function of the light exposure regime by digital colometric reflectance spectroscopy

In-office dental bleaching has been subject of several studies. Generally those studies quantify through visual analysis, the shade reduction of the teeth submitted to different bleaching protocols (light sources, bleaching agent concentrations and irradiation time). The objective of this work is the determination of the influence of four irradiation protocols on the obtainment of better aesthetic results using a colorimetric spectrophotometer that quantifies color changes in each situation imposed. Forty bovine incisors were selected in function of similar anatomic characteristics; a concentrated coffee solution was used to stain the teeth. A commercial spectrophotometer was used to measure the color changes during evolution of the experiment (stain and bleaching phases) and the obtained data was analyzed by the ANOVA test. The obtained data showed the evolution of teeth color during the staining period, as well as, the color reduction that each bleaching protocol achieved. Based on our findings it is possible to conclude that bleaching protocols with larger irradiation periods did not showed significant differences when compared with shorter irradiation protocols, in that way the use of protocols with 30 min or more of consecutive irradiation are not clinically justified and also can cause several side effects.

Evaluation of dental restorations: a comparative study between clinical and digital photographic assessments

The aim of this study was to compare the efficacy of a direct clinical evaluation method with an indirect digital photographic method in assessing the quality of dental restorations. Seven parameters (color, occlusal marginal adaptation, anatomy form, roughness, occlusal marginal stain, luster, and secondary caries) were assessed in 89 Class I and Class II restorations from 36 adults using the modified US Public Health Service/Ryge criteria. Standardized photographs of the same restorations were digitally processed by Adobe Photoshop software, separated into the following four groups and assessed by two calibrated examiners: Group A: The original photograph displayed at 100%, without modifications (IMG100); Group B: Formed by images enlarged at 150% (IMG150); Group C: Formed by digital photographs displayed at 100% (mIMG100), with digital modifications (levels adjustment, shadow and highlight correction, color balance, unsharp Mask); and Group D: Formed by enlarged photographs displayed at 150% with modifications (mIMG150), with the same adjustments made to Group C. Photographs were assessed on a calibrated screen (Macbook) by two calibrated clinicians, and the results were statistically analyzed using Wilcoxon tests (SSPS 11.5) at 95% CI. Results: The photographic method produced higher reliability levels than the direct clinical method in all parameters. The evaluation of digital images is more consistent with clinical assessment when restorations present some moderate defect (Bravo) and less consistent when restorations are clinically classified as either satisfactory (Alpha) or in cases of severe defects (Charlie). Conclusion: The digital photographic method is a useful tool for assessing the quality of dental restorations, providing information that goes unnoticed with the visual-tactile clinical examination method. Additionally, when analyzing restorations using the Ryge modified criteria, the digital photographic method reveals a significant increase of defects compared to those clinically observed with the naked eye. Photography by itself, without the need for enlargement or correction, provides more information than clinical examination and can lead to unnecessary overtreatment.

Constitutive heterochromatin and nucleolus organizer region in the knifefish, Apteronotus albifrons (Pisces, Apteronotidae)

The C-banding and silver staining of the chromosomes of the knifefish Apteronotus albifrons (2n=24), demonstrated the presence of constitutive heterochromatin in the centromeric region of every chromosome, except pair 4, where the entire long arm was darkly stained, the silver stain positive nucleolus organizer region (NOR) being embedded in it. © 1981 Birkhüuser Verlag.

The effect of non-antihypertensive doses of angiotensin converting enzyme inhibitor on myocardial necrosis and hypertrophy in young rats with renovascular hypertension

In renovascular hypertensive rats, low doses of angiotensin converting enzyme (ACE) inhibitors have been found to prevent myocardial hypertrophy independent of blood pressure level. This finding would suggest humoral rather than mechanical control of myocyte growth. The aim of this study was to examine the effect of nonantihypertensive doses of ACE inhibitor on myocardial hypertrophy and necrosis in hypertensive rats. Renovascular hypertension (RHT) was induced in four-week-old Wistar rats. Twenty-eight animals were treated for four weeks with three doses of ramipril (0.01, 0.1 or 1. 0 mg/kg/day, which are unable to lower blood pressure. Fourteen animals were not treated (RHT group). A sham operated, age/sex-matched group was used as control (n = 10). Myocardial histology was analysed in 3 microm thick sections of the ventricle stained with either haematoxylin-eosin, reticulin silver stain or Masson's trichrome. There was a significant correlation between systolic blood pressure and left ventricular to body weight ratio in both sets of animals: untreated plus controls and ramipril-treated rats. ACE inhibition prevented myocyte and perivascular necrosis and fibrosis in a dose-dependent manner. We conclude that myocardial hypertrophy in rats with renovascular hypertension is directly related to arterial pressure, and that this relationship is not affected by nonantihypertensive doses of ACE inhibitor. Myocardial necrosis/fibrosis and coronary artery damage induced by angiotensin II are prevented by ACE inhibitor in a dose-dependent manner, despite the presence of arterial hypertension.

Ki67/KIT double immunohistochemical staining in cutaneous mast cell tumors from Boxer dogs

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Does spinal block through tattooed skin cause histological changes in nervous tissue and meninges?: an experimental model in rabbits

Although there is no documented evidence that tattoo pigments can cause neurological complications, the implications of performing neuraxial anesthesia through tattooed skin are unknown. In this study, we aimed to assess whether spinal puncture performed through tattooed skin of rabbits determines changes over the spinal cord and meninges. In addition, we sought to evaluate the presence of ink fragments entrapped in spinal needles. Thirty-six young male adult rabbits, each weighing between 3400 and 3900 g and having a spine length between 38.5 and 39 cm, were divided by lot into 3 groups as follows: GI, spinal puncture through tattooed skin; GII, spinal puncture through tattooed skin and saline injection; and GIII, spinal puncture through skin free of tattoo and saline injection. After intravenous anesthesia with ketamine and xylazine, the subarachnoid space was punctured at S1-S2 under ultrasound guidance with a 22-gauge 2½ Quincke needle. Animals in GII and GIII received 5 μL/cm of spinal length (0.2 mL) of saline intrathecally. In GI, the needle tip was placed into the yellow ligament, and no solution was injected into the intrathecal space; after tattooed skin puncture, 1 mL of saline was injected through the needle over a histological slide to prepare a smear that was dyed by the Giemsa method to enable tissue identification if present. All animals remained in captivity for 21 days under medical observation and were killed by decapitation. The lumbosacral spinal cord portion was removed for histological analysis using hematoxylin-eosin stain. None of the animals had impaired motor function or decreased nociception during the period of clinical observation. None of the animals from the control group (GIII) showed signs of injuries to meninges. In GII, however, 4 animals presented with signs of meningeal injury. The main histological changes observed were focal areas of perivascular lymphoplasmacyte infiltration in the pia mater and arachnoid. There was no signal of injury in neural tissue in any animal of both groups. Tissue coring containing ink pigments was noted in all GI smears from the spinal needles used to puncture the tattooed skin. On the basis of the present results, intrathecal injection of saline through a needle inserted through tattooed skin is capable of producing histological changes over the meninges of rabbits. Ink fragments were entrapped inside the spinal needles, despite the presence of a stylet.

Maturidade pulmonar e fetal de bezerros da raça holandesa preta e branca tecém-nascidos, a termo e hígidos: análise do líquido amniótico

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Utilização de redes neurais artificiais aplicadas na discriminação de padrões de doenças florestais

Pós-graduação em Ciência Florestal - FCA

Pasteurelose em juvenis de cobias (Rachycentron canadum) criados em tanques-redes no litoral norte do estado de São Paulo - Brasil

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Cytopathology in the diagnosis of oral trichomoniasis in a rock pigeon (columba livia)

A Rock Pigeon (Columba livia) submitted for necropsy had an oral white-yellow mass with a friable surface and putrid odor. Impression smears were performed and tissue samples were collected for histopathology. Cytopathological analysis revealed numerous pyriform protozoa, compatible with Trichomonas gallinae. Protozoans were not evident within the lesions by histopathology after staining the samples with Hematoxylin and Eosin or Gomori methenamine silver (GMS) stain. We conclude that impression smears from avian oral trichomoniasis suspects, even during post-mortem evaluation, can be a useful technique for the diagnosis of this disease.

A importância da atenção farmacêutica após a verificação da qualidade microbiológica de medicamentos contendo paracetamol encontrados em algumas residências de Américo Brasiliense - SP

It is known that a high microbial count can compromise the stability of medicines, thus reducing their therapeutic efficacy. This work tried to demonstrate that the microbial contamination can be directly related to the inadequate handling of the medicines stored in homes, making it possible to draw strategies to reduce the possible risks of medical therapy offering correct information and advising. The objective of this work was to evaluate the quality of the medicines containing paracetamol found in the residences of Américo Brasiliense-SP, using the microbial analysis of non-sterile method described in the Brazilian Pharmacopoeia (1988). The medicine samples (30 samples) were obtained directly from the interviewed local residents, who had received new medicine bottles of the same product. An analysis of viable microorganisms (bacteria and fungus) was carried out to identify pathogens found in the collected samples. Although 90% of the analyzed samples have shown some microbial contamination, the results indicated the absence of pathogenic microorganisms, and the total count of viable microorganisms was below the maximum value for non-sterile (104 UFC/g or mL). It was also verified that the local residents stored the medicines in appropriate places, according to the orientations received when they bought the medicines in pharmacies and drugstores, showing the importance of information for the correct use and conservation of pharmaceuticals.

Cytopathology in the diagnosis of oral trichomoniasis in a Rock Pigeon (Columba livia)

A Rock Pigeon (Columba livia) submitted for necropsy had an oral white-yellow mass with a friable surface and putrid odor. Impression smears were performed and tissue samples were collected for histopathology. Cytopathological analysis revealed numerous pyriform protozoa, compatible with Trichomonas gallinae. Protozoans were not evident within the lesions by histopathology after staining the samples with Hematoxylin and Eosin or Gomori methenamine silver (GMS) stain. We conclude that impression smears from avian oral trichomoniasis suspects, even during post-mortem evaluation, can be a useful technique for the diagnosis of this disease.