Morphology of the arthrodial membrane gland in a Neotropical harvester (Arachnida: Opiliones)

We describe a gland in the arthrodial membrane of the coxa-trochanter articulation in the fourth pair of legs in the Neotropical harvester Mischonyx squalidus Bertkau, 1880. Externally the glandular area has a rough appearance with pores on its surface, with folds of the arthrodial membrane. Internally, its secretory cells have spherical secretory vesicles, smooth endoplasmic reticulum, mitochondria and ducts that exit from the cells and cross the arthrodial membrane. Histochemical tests indicate the presence of proteins and neutral glycoproteins. The function of the gland might be to produce lubricating products that allow better movement of the coxa-trochanter region.

Peritrophic membrane origin in adult bees (Hymenoptera): immunolocalization.

The midgut is a region of the digestive tract of bees with the lumen lined by a peritrophic membrane that is composed of chitin and proteins (peritrophins). The origin of the peritrophins in the midgut of adult bees is unknown. This study used an anti-peritrophin 55-kDa antibody to immunolocalize the sites of the peritrophic membrane synthesis in nine species of adult bees' representatives of different families and sociability levels. In all studied species the peritrophin-55 is produced by digestive cells in the entire midgut in the rough endoplasmic reticulum following transference to Golgi apparatus and released by secretory vesicles, which fuses with the plasma membrane and microvilli. Thus, in the representatives of different groups of bees, the PM is of type I.

Histometric analysis of alveolar bone regeneration with expanded polytetrafluoroethylene (e-PTFE) and latex membranes

AIM: To investigate the amount of connective tissue migrated into the extraction socket using EPTFE and latex membranes. METHODS: Seventeen rats were selected and randomly divided into 3 groups: e-PTFE membrane (n = 6), Latex membrane (n = 6) and Control (no membrane, n=5). After extraction of the maxillary right incisor, the animals of the test groups were subjected to alveolar guided bone regeneration (GBR) surgery and received an expanded polytetrafluoroethylene (e-PTFE) and a latex membrane, respectively. Thirty days after surgery, the animals were killed and histometric analysis was done to evaluate the migration of connective tissue. Data were analyzed statistically by one-way ANOVA and multiple-comparison Tukey's test at 5% significance level. RESULTS: There was statistically significant difference between groups e-PTFE and Latex (p=0.001), and between groups e-PTFE and Control (p=0.012), but no significant difference was found between groups Latex and Control (p=0.416). CONCLUSIONS: The e-PTFE membrane showed better results and appeared more adequate for GBR therapy, forming a barrier to prevent the migration of connective tissue into the extraction socket. The latex membrane, on the other hand, did not show benefits over the control group.

Propriedades tensiométricas comparadas entre fragmentos do centro tendíneo do diafragma, pericárdio fibroso e peritônio parietal de bovinos não conservados e conservados em glicerina / Compared tensiometrical properties between non conserved and glycerin conserved fragments of bovine diaphragmas tendinous center, fibrous pericardium and parietal peritoneum

Objetivou-se descrever o comportamento do centro tendíneo do diafragma, pericárdio fibroso e peritônio parietal de bovinos não conservados e conservados em glicerina a 98% durante 30, 60 e 90 dias submetidos a ensaios mecânicos de tração. Utilizou-se para tanto dez bovinos com idade entre 30 meses e 36 meses, mestiços, machos e fêmeas, coletando-se de cada animal fragmentos das membranas referidas. O centro tendíneo do diafragma e o peritônio parietal não sofreram alteração significante (p>0,05) para os valores de tensão quando comparados os testes de resistência à tração do material não conservado com aqueles conservados em glicerina. Entretanto, todos os tecidos avaliados exibiram aumento significante (p£0,05) para os valores de alongamento quando conservados em glicerina 98% poraté 90 dias. Verificou-se que o pericárdio fibroso é a membrana que suporta as maiores tensões, ou seja, maior força de tração por área desecção. Assim, concluiu-se que a glicerina é eficaz para conservação de membranas biológicas, além de alterar suas propriedades mecânicas.(AU)

The behaviour of the non conserved and 98% glycerin conservedspecimens for periods of 30, 60 and 90 days of bovine diaphragmastendinous center, fibrous pericardium and parietal peritoneumsubmitted to mechanical tests of traction, was observed in ten bovinesbetween 30 months and 36 months of age, crossbreeds, males andfemales, collecting fragments of these aforesaid membranes in eachanimal. The diaphragmas tendinous center and parietal peritoneumdid not suffered significant modification (p>0.05) in the values oftension when compared to the resistance tests of traction of nonconserved and 98% glycerin conserved membranes. However, all theevaluated tissues showed significant increase (p£0.05) of theelongation values when conserved in 98% glycerin for until 90 days.It was also observed that fibrous pericardium is the one whichsupports greaters tensions. So, it to was concluded, that glycerin isefficient to the conservation of biological membranes besidesmodifying its mechanical properties.(AU)

Propriedades tensiométricas comparadas entre fragmentos do centro tendíneo do diafragma, pericárdio fibroso e peritônio parietal de bovinos não conservados e conservados em glicerina / Compared tensiometrical properties between non conserved and glycerin conserved fragments of bovine diaphragma’s tendinous center, fibrous pericardium and parietal peritoneum

Objetivou-se descrever o comportamento do centro tendíneo do diafragma, pericárdio fibroso e peritônio parietal de bovinos não conservados e conservados em glicerina a 98% durante 30, 60 e 90 dias submetidos a ensaios mecânicos de tração. Utilizou-se para tanto dez bovinos com idade entre 30 meses e 36 meses, mestiços, machos e fêmeas, coletando-se de cada animal fragmentos das membranas referidas. O centro tendíneo do diafragma e o peritônio parietal não sofreram alteração significante (p>0,05) para os valores de tensão quando comparados os testes de resistência à tração do material não conservado com aqueles conservados em glicerina. Entretanto, todos os tecidos avaliados exibiram aumento significante (p£0,05) para os valores de alongamento quando conservados em glicerina 98% poraté 90 dias. Verificou-se que o pericárdio fibroso é a membrana que suporta as maiores tensões, ou seja, maior força de tração por área desecção. Assim, concluiu-se que a glicerina é eficaz para conservação de membranas biológicas, além de alterar suas propriedades mecânicas.

Clinical and histologic evaluation of the demineralized freeze-dried bone membrane used for ridge augmentation.

The biologic principle of guided bone regeneration has been successfully used to regenerate alveolar ridges. The objective of this pilot study was to clinically and histologically evaluate the demineralized freeze-dried bone membrane. Four premolar teeth were extracted from two dogs, and the remaining alveolar bone was surgically reduced in width and height to produce Class III ridge defects. After a 2-month healing period, mucoperiosteal flaps were elevated, and demineralized freeze-dried cortical columns were used as space maintainers. Bone membranes were used as barriers. The animals were sacrificed at 3 months and the surgical areas were recovered and processed for histologic evaluation. Results showed ridge augmentation in all sites. Clinically, the augmented areas appeared to have the same hardness as the surrounding bone on the periphery of the experimental site. After elevation of a mucoperiosteal flap, the bone membrane could be seen. Histologically, the bone membrane acted as an efficient barrier, excluding the nonosteogenic tissues. New bone formation underneath the membrane was found in all specimens. This study suggests that a bone membrane in combination with a space maintainer can guide new bone formation to regenerate localized chronic alveolar ridge defects.

Schistosoma mansoni: surface membrane isolation with lectin-coated beads.

Lectins from Lens culinaris and Arachis hypogaea immobilized on polyacrylamide beads were used for selective isolation of glycosylated surface membrane domains of adult Schistosoma mansoni worms, and the method was compared with the membrane isolation procedure developed with polycationic (Affi-Gel) beads. The lentil lectin proved to be suitable for interaction with surface membrane components: an increment in the specific activities of tegumental phosphohydrolases was observed in the bound fraction with respect to that observed in a total worm homogenate. A characteristic polypeptide pattern on gel electrophoresis was also seen, more restricted than that obtained with the bound Affi-Gel fraction. Immobilized peanut lectin was not successful as a method for isolating membrane material from the tegument of adult worms. Solubilization and dissociation of the lentil lectin-bound enzyme markers was achieved after addition of detergent and competing sugars. Glycosylation of the solubilized enzymes was further confirmed by affinity chromatography with fresh lentil lectin-coated beads. These results, together with histochemical evidences, suggest that the active sites of some of these enzymes are located within or close to the cytoplasmic leaflet of the surface tegumental membranes, and allow us to propose a model for the double surface membrane complex where some proteins may be crossing the two bilayers.

Anatomia microscópica da parte membranácea (pars membranacea) do septo interventricular do coraçäo humano / Microscopic anatomy of the pars membranacea of the human heart interventricular septum

A parte membranácea do septo interventricular relaciona-se com as cúspides semilunares aórticas direita e posterior. Pode ser evidenciada por tansluminaçäo pelos seus lados direito e esquerdo. Com o emprego da luz polarizada, postula-se uma estrutura complexa para a parte membranácea, em confronto com a propsota de diferentes autores. A disposiçäo estrutural, tanto das fibras colágenas como das fibras elásticas, permite admitir a área da parte membranácea como uma estrutura estrategicamente situada para fornecer simultaneamente deformaçöes e apoio às câmaras e vasos a ela relacionados

Consideraçoes morfológicas sobre a Pars membranacea do septo interventricular do coraçäo humano / Morphological considerations on the Pars membranacea of the interventricular septum of the human heart

A grande divergência de opiniöes sobre a Pars membranacea em relaçäo a tópicos como: sua topografia, limites, forma, área e espessura nos levou a pesquisar o assunto utilizando-nos de técnicas objetivas. Quanto as áreas da Pars membranacea obtivemos medidas extremas de 2,0 mm2 e 101 mm2, as quais apresentaram estatisticamente uma correlaçäo linear positiva entre dimensöes das áreas e idade dos indivíduos e uma correlaçäo significativa com o grupo étnico que no grupo dos näo brancos as dimensöes das áreas eram maiores. Verificamos quanto a espessura da Pars membranacea uma variabilidade entre 0,37mm e 2,88 mm. Estatisticamente obtivemos uma correlaçäo linear negativa entre a espessura e as dimensöes das áreas da Pars membranacea