Encapsulação da rifampicina em matrizes poliméricas flutuantes obtidas por liofilização a partir de metilcelulose e ftalato de hidroxipropilmetilcelulose. Avaliação da liberação in vitro

Floating multiparticles for oral administration with different compositions were studied from a matricial polymeric system to obtain sustained release. The polymers used in the multiparticles constitution were methylceullose (MC) and hydroxypropylmethylcelullose phthalate (HPMCP) in several proportions. Spherical and isolated structures were obtained using HPMCP/MC in the range from 1:3 to 1: 13. The diameters of the floating multiparticles were in the range from 3 to 3.25 mm, while the non-floating particles were between 1.75 and 2.1 mm. The morphological analysis by confocal microscopy showed that the probable mechanism of drug release was the diffusion from the inner of particles to external media. The encapsulation of hydrophilic model substances (tartrazin and bordeaux S), showed that the maximum incorporation was about 38%, while for the lipophilic model substances (rifampicin) was 45%. The in vitro release of rifampicin in acid medium was dependent on the ratio HPMCP/MC. In alkaline medium the release followed a two-step profile, with slow release in the initial times and subsequent increase in the higher times The initial drug delivery profile was not dependent on the MC/HPMCP ratio and can be related with the release of the antibiotic from multiparticle inner caused by the swelling of polymers by the presence of water in the system. However, afterwards the release proceeds with typical profile of process involving hydrogels systems.

P-077. Myxoma of bone. Review of 17 cases

Myxoma of bone (fibromyxoma) is a slowly growing, locally invasive tumor that almost always occurs in the facial bones. The tumor has a potential to recur, but does not metastasize. The lesion is usually painless but causes slowly progressive swelling, sometimes resulting in severe facial deformity. Aim: Review of myxoma of bone experience in two institutions. Methods: Retrospective chart review of all patients with diagnose of myxoma/fibromyxoma of bone identified in the tumor registry of two referral cancer centers: Hospital Erasto Gaerntner (HEG), Curitiba, PR Brazil and University of Sao Paulo (UNESP), Aracaatuba Campus, Sao Paulo, SP Brazil. We reviewed the age, sex, ace, presenting symptoms, topography of lesion and treatment. Results: From January 1972 to July 2000 we found 17 patients from both institutions that met the diagnostic criteria; 15 from HEG and two from UNESP. The median age was 32 years (range 10-55 years). Eleven patients were male, 14 were white and three were black. Only three patients presented with local pain, the remaining were free of symptoms, presenting only with local tumor. The tumor affected the maxilla in 11 patients (six on the right), the mandible in five and the zygomatic bone in one. All patients were treated by excisional surgery and one patient received adjuvant radiation therapy. Nine patients needed reconstruction after the tumor excision. Five of them were reconstructed with local soft tissue flaps; two received iliac crest autologous bone graft; and two had a microvascularized autologous fibula graft. Conclusion: The myxoma of bone in our experience is a rare tumor and occurs more frequently in the maxilly bone in young males. These findings are consistent with the literature data.

The ultrastructure of the guinea pig rete testis

The chambers of the rete testis (RT) of guinea pig are lined by a simple epithelium, whose cells are squamous, cubical and columnar in shape. The epithelial cells with distinct shapes were counted and the quantitative analysis of the number of these cells showed relative predominance of cubical cells. The ultrastructural observations showed predominance of membrane interdigitations among the epithelial cells. These cells present common cytoplasmic organelles. The Golgi complex polarity is typical with observation of electronlucent vesicles on the Golgi cis face closely related to rough endoplasmic reticulum (ER) lamellae, mitochondria and large number of polysomes on the Golgi trans face. These related structures present in Golgi area of RT cells suggest secretory activity which maybe occurs in the RT epithelium. Endocytotic process also occurs in the RT and this function probably concerns the uptake of substances and resorption of seminiferous fluid. Apical cilia present in RT epithelium cells are related with fluid transport and perhaps with chemoreception. Presence of spermatozoa portions enclosed into the cytoplasm of some epithelium cells has been refferred to as spermatophagy. The RT complex is mainly supported by loose connective tissue, with collagen fibres and some Leydig cells. Leydig cells are adjacent to the network channels of the septal part of the RT and apparently are able to secrete inside the RT lumen.

Standardization of platelet parameters determination in blood samples collected with EDTA

The Abbott Cell-Dyn 3000 automated hematological analyzer prepares a histogram of platelet volume, which is measured by a technique using electrical impedance, inferring from its platelet count (PLT), mean platelet volume (MPV) and platelet distribution width (PDW). This equipment also calculates the plateletcrit (PCT). These platelet parameters may be important to evaluate platelet function, but they require standardization, because platelets swell when in contact with ethylenediaminetetra-acetic acid salts, hence an increase in blood sample storage time produces artificially increased results. To assess the effect of storage time on MPV, PLT, PDW and PCT, blood samples from 23 sickle cell anemia patients during steady state (Group I) and 50 from healthy controls (Group II) were placed in Vacutainer® tubes with dipotassium ethylenediaminetetra-acetic acid and measured over a period of 1440 minutes (24 h) at the following times: immediately after the venipuncture (time 0), 15, 30, 60, 120, 240, 360, 480 and 1440 minutes. The mean values of MPV and PCT were significantly increased (p<0.00001) along the storage time in both groups. The mean values of PLT and PDW were practically stable (p>0.05) throughout the storage time in both groups.

The ultrastructure of the intestinal epithelium in Oreochromis niloticus on a diet with different concentrations of zinc

The effects of diets with variable zinc levels on the midgut epithelial cells were studied in Oreochromis niloticus L. One hundred and twenty fry of tilapia were apportioned into 4 experimental groups (I, II, III and IV groups), with 30 fish in each treatment, 5 replicate aquaria per treatment containing 6 fish each. The animals of the 4 groups were fed with isonitrogenous (30% crude protein) and isoenergetic (3000 Kcal/Kg of digestible energy) diets with increasing quantities of zinc (44.59; 149.17; 309.93; 599.67 mg Zn/kg of diet), twice a day, for 93 days. Three fish from each group were sacrificed at 36, 66 and 93 days and samples of midgut were removed for ultrastructural analysis. After 93 days of treatment, 3 animals of each experimental group were used for the analysis of zinc concentration by atomic absorption spectrophotometry. The comparative relative index (CRI) revealed that the animals in groups II, III and IV contained, respectively, 1.99%, 34.67% and 22.78% more zinc than the mean concentration in animals from group I. The ultrastructural analysis showed enterocytes with swelling of smooth surfaced endoplasmic reticulum and dilated mitochondria with variable matrix rarefaction and cristae number reduction in the fish exposed to 599.67 mg Zn/Kg of diet at 66 and 93 days of treatment.

Relation between the compaction rate and physical and mechanical properties of particleboards

The compaction rate, the relation between the density of the wood panel and the density of the wood used for producing the particles, is an indicator of the product's densification. Among the various types of wood panels, particleboards are widely employed in the lumber industry, mainly for the furniture production. This paper presents a study of the relation between the compaction rate and the properties of tensile strength perpendicular to surface, Modulus of Rupture (MOR) and Modulus of Elasticity (MOE) obtained from a static bending test, thickness swelling and water absorption (2 and 24 hours). These properties were calculated according to the Brazilian ABNT, NBR 14810 standard. Particleboards were produced using the species Pinus elliotti and adhesive ureaformaldehyde. The relation was established by a multiple linear regression, and the most appropriate statistical models were determined. The estimated models indicate statistically significant effects of water absorption in 2 hours and MOR in the particleboards' compaction rate.

COX24 codes for a mitochondrial protein required for processing of the COX1 transcript

In most strains of Saccharomyces cerevisiae the mitochondrial gene COX1, for subunit 1 of cytochrome oxidase, contains multiple exons and introns. Processing of COX1 primary transcript requires accessory proteins factors, some of which are encoded by nuclear genes and others by reading frames residing in some of the introns of the COX1 and COB genes. Here we show that the low molecular weight protein product of open reading frame YLR204W, for which we propose the name COX24, is also involved in processing of COX1 RNA intermediates. The growth defect of cox24 mutants is partially rescued in strains harboring mitochondrial DNA lacking introns. Northern blot analyses of mitochondrial transcripts indicate cox24 null mutants to be blocked in processing of introns aI2 and aI3. The dependence of intron aI3 excision on Cox24p is also supported by the growth properties of the cox24 mutant harboring mitochondrial DNA with different intron compositions. The intermediate phenotype of the cox24 mutant in the background of intronless mitochondrial DNA, however, suggests that in addition to its role in splicing of the COX1 pre-mRNA, Cox24p still has another function. Based on the analysis of a cox14-cox24 double mutant, we propose that the other function of Cox24p is related to translation of the COX1 mRNA. © 2006 by The American Society for Biochemistry and Molecular Biology, Inc.

The plant energy-dissipating mitochondrial systems: Depicting the genomic structure and the expression profiles of the gene families of uncoupling protein and alternative oxidase in monocots and dicots

The simultaneous existence of alternative oxidases and uncoupling proteins in plants has raised the question as to why plants need two energy-dissipating systems with apparently similar physiological functions. A probably complete plant uncoupling protein gene family is described and the expression profiles of this family compared with the multigene family of alternative oxidases in Arabidopsis thaliana and sugarcane (Saccharum sp.) employed as dicot and monocot models, respectively. In total, six uncoupling protein genes, AtPUMP1-6, were recognized within the Arabidopsis genome and five (SsPUMP1-5) in a sugarcane EST database. The recombinant AtPUMP5 protein displayed similar biochemical properties as AtPUMP1. Sugarcane possessed four Arabidopsis AOx1-type orthologues (SsAOx1a-1d); no sugarcane orthologue corresponding to Arabidopsis AOx2-type genes was identified. Phylogenetic and expression analyses suggested that AtAOx1d does not belong to the AOx1-type family but forms a new (AOx3-type) family. Tissue-enriched expression profiling revealed that uncoupling protein genes were expressed more ubiquitously than the alternative oxidase genes. Distinct expression patterns among gene family members were observed between monocots and dicots and during chilling stress. These findings suggest that the members of each energy-dissipating system are subject to different cell or tissue/organ transcriptional regulation. As a result, plants may respond more flexibly to adverse biotic and abiotic conditions, in which oxidative stress is involved. © The Author [2006]. Published by Oxford University Press [on behalf of the Society for Experimental Biology]. All rights reserved.

Antisperm antibodies in infertile men and their correlation with seminal parameters

Aim: Antisperm antibodies (ASA) in males cause the autoimmune disease 'immune infertility'. The present study intended to detect the presence of ASA and their incidence in men with unexplained infertility, as well as to evaluate the correlation between the presence of ASA and semen parameter alterations. Methods: Blood and sperm assessment were collected to carry out a direct and indirect mixed antiglobulin reaction (MAR) test and semen analysis in infertile and fertile men from the University Hospital of the Faculty of Medicine, Sao Paulo State University, Sao Paulo. Results: In the MARtest, 18.18% of infertile men were positive for ASA. In fertile men, no positivity was found. A significant correlation between the presence of ASA with an increased white blood cell count plus a decreased hypoosmotic swelling test result was observed. Conclusions: The results indicate that ASA are involved in reduced fertility. It is not ASA detection per.se that provides conclusive information about the occurrence of damage to fertility. The correlation between infertility and altered seminal parameters reinforce the ASA participation in this pathology. © 2007 The Authors Journal compilation. © 2007 Japan Society for Reproductive Medicine.

Congenital ranula: A case report

The purpose of this study was to report a case of bilateral swelling on the floor of the mouth of a 7-month-old patient. The lesion was congenital and had started to cause feeding problems. After the clinical diagnosis of ranula was made, the lesion was marsupialized. The obtained specimen was submitted for histopathological examination, which revealed an epithelial-lined cystic lesion. These results led to the final diagnosis of mucus retention cyst. After an 8-year follow-up period, the patient is in good general health with no recurrences.

Imprint cytology of osteosarcoma of the jaw: A case report

Introduction. Osteosarcomas are highly malignant bone-forming neoplasms that account for about 20% of all sarcomas. In light of their aggressive behavior, early diagnosis is crucial for determining adequate treatment. Dental professionals may be the first to detect jaw osteosarcomas in their initial stages. The aim of this case report is to draw attention to the possibility of diagnosing this tumor based on clinical, radiographical and cytological characteristics before confirmation by histology. Case presentation. A 24-year-old Afro-Brazilian man presented with swelling and pain on the left side of the mandible in the region of the third molar (tooth 38). Radiography showed a poorly delimited intraosseous lesion with radiolucent and radiopaque areas. The cytological aspects were consistent with the diagnosis of osteosarcoma, which was confirmed by biopsy. Conclusion. Imprint cytology was found to be a reliable, rapid and easy complementary examination. An early diagnosis of osteosarcoma of the jaw is fundamental to the early determination of an adequate treatment. © 2009 Cabral et al; licensee BioMed Central Ltd.

Glucocorticoids in vivo induce both insulin hypersecretion and enhanced glucose sensitivity of stimulus-secretion coupling in isolated rat islets

Although glucocorticoids are widely used as antiinflammatory agents in clinical therapies, they may cause serious side effects that include insulin resistance and hyperinsulinemia. To study the potential functional adaptations of the islet of Langerhans to in vivo glucocorticoid treatment, adult Wistar rats received dexamethasone (DEX) for 5 consecutive days, whereas controls (CTL) received only saline. The analysis of insulin release in freshly isolated islets showed an enhanced secretion in response to glucose in DEX-treated rats. The study of Ca2 2+ signals by fluorescence microscopy also demonstrated a higher response to glucose in islets from DEX-treated animals. However, no differences in Ca2 2+signals were found between both groups with tolbutamide or KCl, indicating that the alterations were probably related to metabolism. Thus, mitochondrial function was explored by monitoring oxidation of nicotinamide dinucleotide phosphate autofluorescence and mitochondrial membrane potential. Both parameters revealed a higher response to glucose in islets from DEX-treated rats. The mRNA and protein content of glucose transporter-2, glucokinase, and pyruvate kinase was similar in both groups, indicating that changes in these proteins were probably not involved in the increased mitochondrial function. Additionally,weexplored the status of Ca2 2+-dependent signaling kinases. Unlike calmodulin kinase II, we found an augmented phosphorylation level of protein kinase Cα as well as an increased response of the phospholipase C/inositol 1,4,5-triphosphate pathway in DEX-treated rats. Finally, an increased number of docked secretory granules were observed in the β-cells of DEX animals using transmission electron microscopy. Thus, these results demonstrate that islets from glucocorticoid-treated rats develop several adaptations that lead to an enhanced stimulus-secretion coupling and secretory capacity. Copyright © 2010 by The Endocrine Society.

Retention mucocele on the lower lip associated with inadequate use of pacifier

Mucocele forms because of salivary gland mucous extravasation or retention and is usually related to trauma in the area of the lower lips. Ruptured ducts release the mucous that accumulates into adjacent tissues, leading to swelling. This report describes a large mucocele involving the lower lip, which was produced in a child by incorrect use of a pacifier. A few important concepts are discussed to help clinicians in the diagnosis and treatment of this pathology. © 2010 Dermatology Online Journal.

A comparative study of myocardial function and morphology during fasting/refeeding and food restriction in rats

Background: This study compared the influence of fasting/refeeding cycles and food restriction on rat myocardial performance and morphology. Methods: Sixty-day-old male Wistar rats were submitted to food ad libitum (C), 50% food restriction (R50), and fasting/refeeding cycles (RF) for 12 weeks. Myocardial function was evaluated under baseline conditions and after progressive increase in calcium and isoproterenol. Myocardium ultrastructure was examined in the papillary muscle. Results: Fasting/refeeding cycles maintained rat body weight and left ventricle weight between control and food-restricted rats. Under baseline conditions, the time to peak tension (TPT) was more prolonged in R50 than in RF and C rats. Furthermore, the maximum tension decline rate (-dT/dt) increased less in R50 than in RF with calcium elevation. While the R50 group showed focal changes in many muscle fibers, such as the disorganization or loss of myofilaments, polymorphic mitochondria with disrupted cristae, and irregular appearance or infolding of the plasma membrane, the RF rats displayed few alterations such as loss or disorganization of myofibrils. Conclusion: Food restriction promotes myocardial dysfunction, not observed in RF rats, and higher morphological damage than with fasting/refeeding. The increase in TPT may be attributed possibly to the disorganization and loss of myofibrils; however, the mechanisms responsible for the alteration in -dT/dt in R50 needs to be further clarified. © 2010 Elsevier Inc. All rights reserved.