Trajectory of Water- and Fat-Soluble Dyes in the Grass-Cutting ant Atta capiguara (Hymenoptera, Formicidae): Evaluation of Infrabuccal Cavity, Post-Pharyngeal Glands and Gaster

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Contribution of the study of the styloid prominence in the posterior tympanic cavity

70 human temporal bones were analyzed with the aid of an otologic microscope. The styloid prominence was found to be extremely variable in shape, location and occurrence. Depending on the degree of development, the prominence establishes important relationships with the sinus tympani, with the fossula of the cochlear fenestra, and with the suprapyramidal recess. Serial sections were used to study the relationship of the styloid process with the facial nerve inside the bony mass of the mastoid portion of the temporal bone.

Numerical and experimental analysis of natural convection in a cavity with flush mounted heat sources on a side wall

This work considers a problem of interest in several technological applications such as the thermal control of electronic equipment. It is also important to study the heat transfer performance of these components under off-normal conditions, such as during failure of cooling fans. The effect of natural convection on the flow and heat transfer in a cavity with two flush mounted heat sources on the left vertical wall, simulating electronic components, is studied numerically and experimentally. The influence of the power distribution, spacing between the heat sources and cavity aspect ratio have been investigated. An analysis of the average Nusselt number of the two heat sources was performed to investigate the behavior of the heat transfer coefficients. The results obtained numerically and experimentally, after an error analysis, showed a good agreement.

Peritoneal effusion in a dog secondary to visceral mast cell tumor: A case report

BACKGROUND: Mast cell tumor, one of the most common skin tumors in dogs, may also be found in visceral sites (mainly spleen and liver). When a visceral mast cell tumor is present, neoplastic mast cells may be found in any effusion secondary to the tumor. Therefore, the diagnosis may be made by cytologic analysis of the effusion. CASE: An 8-year-old, spayed, female Siberian husky presented with a peritoneal effusion secondary to a visceral mast cell tumor. Seven months earlier, the dog had presented with a cutaneous nodule diagnosed as a well-differentiated mast cell tumor. The peritoneal fluid was classified as a transudate. Numerous neoplastic mast cells were found in the effusion. Although the mast cell tumor presented with characteristics of the well-differentiated tumor, its biologic behavior was that of a malignant tumor. CONCLUSION: Care should be taken to evaluate the prognosis of mast cell tumors in dogs since their biologic behavior is extremely variable.

Gelatinous polyethylene in the treatment of the anophthalmic cavity

PURPOSE: Gelatinous polyethylene (GP) has been used as an orbital implant to evaluate volume maintenance and tissue reaction in the anophthalmic socket in a rabbit model. METHODS: Twenty-eight Norfolk white rabbits underwent unilateral evisceration with placement of 2ml GP (GP group - 16 animals) or 2ml 0.9% sodium chloride solution (Control group - 12 animals). Animal behavior, postoperative tissue response and socket conditions were evaluated. The animals were sacrificed at 7, 15, 30 and 60 days after the surgery and the bulbs were enucleated; volume maintenance and histopathological evaluation were done in the enucleated bulbs. The results were submitted to statistical analysis. RESULTS: All animals showed normal behavior. The orbital volume maintenance was better in the GP group. Histopathology in the GP animals showed mild tissue inflammation throughout the evaluation period and a thin pseudocapsule formation surrounding the orbital implant material. CONCLUSION: The clinical findings, good orbital volume maintenance and mild inflammatory tissue response make GP a good choice to replace the lack of volume in anophthalmic socket reconstruction.

Secretion of tumor necrosis factor-alpha by mouse peritoneal macrophages in the presence of dental sealers, sealapex and endomethasone

After filling root canals, the healing process depends on the chemical composition or physical-chemical properties of the material used, among other factors. All root canal sealers, whether solid or plastic, are foreign matter for the body if they remain in permanent contact with apical and periapical tissues. As a result, the first organic reaction that occurs is an attempt to phagocytize the material. During phagocytosis, macrophages release a large number of cell mediators into the area, among which are cytokines that are essential in intercellular communication and in many physiological and pathophysiological processes. One of these cytokines is tumor necrosis factor-alfa (TNF-α), which acts through links to specific receptors on the cell membrane initiating a cascade of events leading to induction, activation, or inhibition of numerous cytokine-regulated genes in the cell nucleus. The release of TNF-α in a cell culture of mouse peritoneal macrophages incubated with three concentrations (25, 50, and 100 mg/ml) of two endodontic sealers was measured. The solutions containing the calcium hydroxide-based root canal sealer (Sealapex) released fewer units of TNF-α than solutions containing the zinc oxide and eugenol-based sealer (Endomethasone).

Prevalence of yeasts in the oral cavity of children treated with inhaled corticosteroids

The aim of this study was to observe the prevalence of Candida spp. in the oral cavity of children undergoing treatment with inhaled corticosteroids. Thirty children treated with inhaled corticosteroids and thirty control children were studied. Saliva samples were collected through oral rinses with phosphate buffered saline (PBS). The samples were plated on Sabouraud's dextrose agar and incubated at 37 degrees C for 48 h. After this period, the number of colony-forming units per ml (cfu/ml) of saliva was calculated. The isolates were identified by phenotypic characterization. Candida spp. was isolated from 43.33% of the samples of children treated with corticosteroids, with a mean of 780 cfu/ml of saliva, and from 30% of the samples of the control group, with a mean of 560 cfu/ml of saliva. No significant statistical difference was observed between the groups. C. albicans was the prevalent species in both groups, followed by C. guilliermondii, C. parapsilosis and C. stellatoidea. Furthermore, Rhodotorula rubra and C. lusitaniae were also isolated from the treated group. We concluded that there was no significant increase in the prevalence and number of Candida spp. in the oral cavity of children treated with inhaled corticosteroids.

Increased implantation and pregnancy rates obtained by placing the tip of the transfer catheter in the central area of the endometrial cavity

The influence of endometrial cavity length (ECL) on implantation and pregnancy rates after 400 embryo transfers was studied prospectively in a population with the indication of IVF/intracytoplasmic sperm injection (ICSI). The tip of the transfer catheter was placed above or below the half point of the ECL in a randomized manner. Two analyses were performed: (i) absolute position (AP); embryo transfers were divided into three groups according to the distance between the end of the fundal endometrial surface and the catheter tip (DTC - distance tip catheter): AP 1 (n = 212), 10-15 mm; AP 2 (n = 158), 16-20 mm; and AP 3 (n = 30), ≥21 mm. (ii) relative position (RP) - embryo transfers were divided into four groups according to their RP [RP = (DTC/ECL) × 100]: RP 1 (n = 23), ≤40%; RP 2 (n = 177), 41-50%; RP 3 (n = 117), 51-60%; and RP 4 (n = 83), ≥61%. Analysis based on relative distance revealed significantly higher implantation and pregnancy rates (P < 0.05) in more central areas of the ECL. However, analysis based on absolute position did not reveal any difference. In conclusion, the present results demonstrated that implantation and pregnancy rates are influenced by the site of embryo transfer, with better results being obtained when the catheter tip is positioned close to the middle area of the endometrial cavity. In this respect, previous analysis of the ECL is the fundamental step in establishing the ideal site for embryo transfers.

Experimental candidosis and recovery of Candida albicans from the oral cavity of ovariectomized rats

The aim of this study was to analyze the development of candidosis and the recovery of C. albicans from the oral cavity of ovariectomized and sham-ovariectomized rats. One hundred aiid twenty-four rats originally negative for Candida spp. in the oral cavity were divided into two groups: ovariectomized and sham-ovariectomized. Fifty-eight ovariectomized and the same quantity of sham-ovariectomized rats were inoculated with C. albicans for the study of candidosis development and recovery of yeast. Four animals from each group were not inoculated with yeast suspension and were submitted to tongue dorsum morphologic analysis by optical and scanning electron microscopy. The development of candidosis in the tongue dorsum was observed by optical and scanning electron microscopy in the periods of 6 hr, 24 hr, 7 days and 15 days after the last inoculation. Recovery of C. albicans was performed by oral samples plating on Sabouraud agar after 1,2, 5 and 7 days and progressively at each 15-day interval until negative cultures for yeasts were obtained. The results were analyzed by Mann-Whitney and Student's t tests. The tongue dorsum of sham-ovariectomized and ovariectomized rats, not infected by Candida, presented normal aspect. Among the infected rats, the ovariectomized group showed less occurrence of candidosis lesions and lower recovery of C. albicans from the oral cavity in relation to the sham-ovariectomized group. It could be concluded that candidosis was less frequent from the oral cavities of ovariectomized rats in relation to sham-ovariectomized.

Implantation sites after embryo transfer into the central area of the uterine cavity

A total of 63 pregnancies (47 singleton, 15 twin, 1 triplet) from intracytoplasmic sperm injection cycles were analysed. In all embryo transfers, the catheter was introduced into the endometrial cavity guided by abdominal ultrasound, with the catheter tip placed at the middle point of the endometrial cavity. Gestational sacs (GS) were located 21-24 days after transfer (gestational age = 5 weeks) by two-dimensional and three-dimensional transvaginal ultrasound. The uterine cavity was divided into three parts: upper, middle and lower. Furthermore, the upper region was subdivided into right, middle and left areas, and the middle region was subdivided into right and left areas. The frequency of gestational sacs in each area was evaluated. In singleton pregnancies 66.0% (31/47) of the GS were detected in the upper region, 29.8% (14/47) in the middle region and 4.2% (2/47) in the lower region. In multiple pregnancies (twins and triplet) 45.5% (15/33) of the GS were detected in the upper region, 51.5% (17/33) in the middle region and 3.0% (1/33) in the lower region. In conclusion, the results demonstrate that when embryos are transferred to the central area of the uterine cavity there is an increase in implantation rate in the middle region compared with the rate expected in naturally conceived pregnancies (9-15%).

Influence of cavity preparation and curing method on the marginal seal of resin composite restorations: an in vitro evaluation.

OBJECTIVE: To evaluate the influence of cavity design and photocuring method on the marginal seal of resin composite restorations. METHOD AND MATERIALS: Seventy-two bovine teeth were divided into 2 groups: group 1 received box-type cavity preparations, and group 2 received plate-type preparations. Each group was divided into 3 subgroups. After etching and bonding, Z250 resin composite (3M Espe) was applied in 2 equal increments and cured with 1 of 3 techniques: (1) conventional curing for 30 seconds at 650 mW/cm2; (2) 2-step photocuring, in which the first step was performed 14 mm from the restoration for 10 seconds at 180 mW/cm2 and the second step was performed in direct contact for 20 seconds at 650 mW/cm2; or (3) progressive curing using Jetlite 4000 (J. Morita) for 8 seconds at 125 mW/cm2 and then 22 seconds at 125 mW/cm2 up to 500 mW/cm2. The specimens were thermocycled for 500 cycles and then submitted to dye penetration with a 50% silver nitrate solution. Microleakage was assessed using a stereomicroscope. Data were analyzed using analysis of variance and Tukey test (5% level of significance). RESULTS: A statistically significant difference was found between groups when a double interaction between photocuring and cavity preparation was considered (P = .029). CONCLUSIONS: No one type of cavity preparation or photocuring method prevented micro-leakage. The plate-type preparation showed the worst dye penetration when conventional and progressive photocuring methods were used. The best results were found using the 2-step photocuring with the plate-type preparation.

Presence of Candida spp. in infants oral cavity and its association with early childhood caries

Candida spp., mainly C. albicans, colonizes oral cavity of infants. Transmission by mother to childbirth, pacifier use, feeding habits and caries are factors related to Candida oral colonization. Some researches related that early childhood caries favor the oral colonization of C. albicans. The present literature review described the presence of Candida spp. in oral cavity of infants and its association with early childhood caries (ECC). The literature was searched for original papers relating Candida, pacifier and baby bottle usage and ECC.The articles, were selected using Bireme and Medline databases. Manual tracing of references cited in key papers was also elicited It can be concluded that Candida spp. colonization in the infants'oral cavity especially C. albicans, can be related to the pacifier usage, feeding habits caries lesion. The early childhood caries favor the C. albicans colonization, although it's role in the carious process need further studies to be elucidate scientifically.

Influence of the power level of an ultra-sonic system on dental cavity preparation

The aim of this study was to evaluate the shape of dental cavities made with the CVDentus® system using different ultrasound power levels. One standard cavity was made on the buccal aspect of 15 bovine incisors with a CVDentus® cylindrical bur (82142). The sample was divided into three groups: G1 - ultrasound with power II; G2 - ultrasound with power III; and G3 - ultrasound with power IV. A standardizing device was used to obtain standardized preparations and ultrasound was applied during one minute in each dental preparation. The cavities were sectioned in the middle, allowing observation of the cavity's profile with a magnifying glass, and width and depth measurement using the Leica Qwin program. The Kruskal-Wallis (p < 0.05) and Dunn statistical analyses demonstrated differences between the dental cavity shapes when powers III and IV were used. However, the cavities that were made with power III presented dimensions similar to those of the bur used for preparation. We concluded that the power recommended by the manufacturer (III) is the most adequate for use with the CVDentus® system.