Response of human alveolar bone-derived cells to a novel poly(vinylidene fluoride-trifluoroethylene)/barium titanate membrane

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

Experimental lamellar keratoplasty in rabbits using microfibrilar cellulose membrane: clinical, morphological and immunohistochemical findings

Avaliaram-se aspectos clínicos, histopatógicos e imunoistoquímicos da córnes de coelhos da raça Nova Zelândia adultos e machos em ceratoplastias lamelares com membrana de celulose microfibrilar. Trinta animais distribuídos em cinco grupos (n=6) foram estudados por até 60 dias de pós-operatório. A avaliação clínica revelou manifestações moderadas de edema, blefaroespasmo e fotofobia ao segundo dia, evoluindo para formas discretas ou ausentes a partir do sétimo dia, período em que se observou, clinicamente, reparo do defeito corneal. A histopatologia revelou uma fina camada de células escamosas, recobrindo a área lesada já aos sete dias, com discreto infiltrado de células polimorfonucleares. Observaram-se vasos no epitélio a partir do 15o dia, com regressão ao 48o dia. A marcação com o anticorpo Ki67 mostrou aumento de células em proliferação aos 15 dias no epitélio e aos 30 dias no estroma. Nesse período, ocorreram remodelamento e adesão epitealial. Considerando a boa integração do implante, admite-se a membrana de celulose como um bom material a ser utilizado em ceratoplastia lamellar.

Agarose gel electrophoresis of cerebrospinal fluid proteins of dogs after sample concentration using a membrane microconcentrator technique

Background: Cerebrospinal fluid (CSF) is produced in the cerebral ventricles through ultrafiltration of plasma and active transport mechanisms. Evaluation of proteins in CSF may provide important information about the production of immunoglobulins within the central nervous system as well as possible disturbances in the blood-brain barrier. Objective: the objective of this study was to measure the concentration and fractions of protein in CSF samples using a membrane microconcentrator technique followed by electrophoresis, and to compare the protein fractions obtained with those in serum. Methods: CSF samples from 3 healthy dogs and 3 dogs with canine distemper virus infection were concentrated using a membrane microconcentrator having a 0.5 to 30,000 d nominal molecular weight limit (Ultrafree, Millipore, Billerica, MA, USA). Protein concentration was determined before and after concentration. Agarose gel electrophoresis was done on concentrated CSF samples, serum, and serial dilutions of one of the CSF samples. Results: Electrophoretic bands were clearly identified in densitometer tracings in CSF samples with protein concentrations as low as 1.3 g/dL. The higher CSF protein concentration in dogs with distemper was mainly the result of increased albumin concentration. Conclusion: the microconcentrating method used in this study enables characterization of the main protein fractions in CSF by routine electrophoresis and may be useful for interpreting the underlying cause of changes in CSF protein concentrations

CYTOPLASMIC AND PLASMA-MEMBRANE ULTRASTRUCTURE OF PARACOCCIDIOIDES-BRASILIENSIS YEAST-PHASE CELLS AS REVEALED BY FREEZE-ETCHING

Using a freeze-etch technique the cytoplasmic and plasma membrane ultrastructure of Paracoccidiodies brasiliensis yeast-phase cells was studied. The multinucleate yeast-phase cells which grow by simultaneous multiple budding, like those of Mucor sp. contain several nuclei, mitochondria, well-developed ER, small vacuoles and lipid droplets. Complex structures with no apparent connexion to the plasma membrane of P. brasiliensis usually lack inveginations, but invaginations which do occur are always rod-shaped which indicates P. brasiliensis to be of either ascomycetous or basidiomycetous origin.

QUANTIFICATION OF IMMUNOGLOBULIN-A IN CHORIOAMNIOTIC MEMBRANE OF PATIENTS WITH PREMATURE RUPTURE OF MEMBRANES

Objective: the proposal was to study the presence of immunoglobulin A (IgA) in the chorioamniotic membrane of healthy postpartum women with premature rupture of the chorioamniotic membrane (FROM). Method: A single radial immunodiffusion technique was used to quantify the IgA in the chorioamniotic membrane tissues. Results: the level of IgA was approximately 10 times higher in patients whose membranes had been ruptured for > 10 h (24.58 mg/dl). These results were compared with those of a previously published study where the mean of amount of IgA was 2.52 mg/dl in membranes of patients with rupture < 10 h. Our results show that IgA began to rise after 10-15 h following rupture. Conclusion: Although more studies need to be performed our data indicate that the increasing IgA in our patients after 10 h of latency probably represents the beginning of an ascending colonization of bacteria which could be the source of future infection.