Susceptibility/resistance of Anticarsia gemmatalis larvae to its nucleopolyhedrovirus (AgMNPV): Structural study of the peritrophic membrane

This investigation compares the peritrophic membrane (PM) morphology along the midgut of susceptible (SL) and resistant (RL) Anticarsia gemmatalis larvae to the AgMNPV. The PM increased the thickness from the anterior to the posterior midgut region in both insects strain; however, the intensity of FITC-WGA reaction of the PM in the RL were greater than in SL. The PM in RL was ultrastructurally constituted by several layers of fibrous/vesicular materials in comparison with the few ones in SL. Our results showed that the structure of PM in the RL could be one of the resistance barriers to AgMNPV. © 2007.

Reconstruction of Mandibular Segmental Defects Using the Guided-Bone Regeneration Technique With Polylactide Membranes and/or Autogenous Bone Graft: A Preliminary Study on the Influence of Membrane Permeability

Purpose: Bone maintenance after mandibular reconstruction with autogenous iliac crest may be disappointing due to extensive resorption in the long term. The potential of the guided-bone regeneration (GBR) technique to enhance the healing process in segmental defects lacks comprehensive scientific documentation. This study aimed to investigate the influence of polylactide membrane permeability on the fate of iliac bone graft (BG) used to treat mandibular segmental defects. Materials and Methods: Unilateral 10-mm-wide segmental defects were created through the mandibles of 34 mongrel dogs. All defects were mechanically stabilized, and the animals were divided into 6 treatment groups: control, BG alone, microporous membrane (poly L/DL-lactide 80/20%) (Mi); Mi plus BG; microporous laser-perforated (15 cm2 ratio) membrane (Mip), and Mip plus BG. Calcein fluorochrome was injected intravenously at 3 months, and animal euthanasia was carried out at 6 months postoperatively. Results: Histomorphometry showed that BG protected by Mip was consistently related to larger amounts of bone compared with other groups (P ≤ .0001). No difference was found between defects treated with Mip alone and BG alone. Mi alone rendered the least bone area and reduced the amount of grafted bone to control levels. Data from bone labeling indicated that the bone formation process was incipient in the BG group at 3 months postoperatively regardless of whether or not it was covered by membrane. In contrast, GBR with Mip tended to enhance bone formation activity at 3 months. Conclusions: The use of Mip alone could be a useful alternative to BG. The combination of Mip membrane and BG efficiently delivered increased bone amounts in segmental defects compared with other treatment modalities. © 2008 American Association of Oral and Maxillofacial Surgeons.

Treatment of gingival recession with collagen membrane and DFDBA: A histometric study in dogs

In a previous study, we evaluated the findings related to the use of resorbable collagen membranes in humans along with DFDBA (demineralized freeze-dried bone allograft). The aim of this subsequent study was to histometrically evaluate in dogs, the healing response of gingival recessions treated with collagen membrane + DFDBA (Guided Tissue Regeneration, GTR) compared to a coronally positioned flap (CPF). Two types of treatment were randomly carried out in a split-mouth study. Group 1 was considered as test (GTR: collagen membrane + DFDBA), whereas Group 2 stood for the control (only CPF). The dogs were given chemical bacterial plaque control with 0.2% chlorhexidine digluconate during a 90-day repair period. Afterwards, the animals were killed to obtain biopsies and histometric evaluation of the process of cementum and bone formation, epithelial migration and gingival level. A statistically significant difference was found between groups with a larger extension of neoformed cementum (GTR = 32.72%; CPF = 18.82%; p = 0.0004), new bone (GTR = 23.20%; CPF = 09.90%; p = 0.0401) and with a smaller area of residual gingival recession in the test group (GTR = 50.69%; CPF = 59.73%; p = 0.0055) compared to the control group. The only item assessed that showed no statistical difference was epithelial proliferation on the root surface, with means of 15.14% for the GTR group and 20.34% for the CPF group (p = 0.0890). Within the limits of this study we concluded that the treatment of gingival recession defects with GTR, associating collagen membrane with DFDBA, showed better outcomes in terms of a larger extension of neoformed cementum and bone, as well as in terms of a smaller proportion of residual recessions.

Evaluation of Sperm Kinetics and Plasma Membrane Integrity of Frozen Equine Semen in Different Storage Volumes and Freezing Conditions

In the present study, different freezing systems (Styrofoam box and Mini Digitcool ZH 400) and storage volumes (0.5- and 0.25-mL straws) were compared with regard to sperm kinetics and plasma membrane integrity of frozen and thawed semen. For that, three ejaculates from four animals were frozen in Styrofoam box and Mini Digitcool ZH 400 machine. The 0.5-mL straws were thawed at 46°C for 20 seconds, and the 0.25-mL straws were thawed at 46°C for 12 seconds. Statistical analysis was performed using program R of descriptive analysis box plot, followed by analysis of variance using PROC MIXED of SAS 9.1 package. Variances of 5% were considered as different. There was no interaction between the straw sizes and volumes; however, statistical differences were observed between the semen storage volumes. The 0.5-mL straws had higher total motility (%), progressive motility (%), average path velocity (μm/s), straight-line velocity (μm/s), curvilinear velocity (μm/s), and rapid sperm percentage (%) than the 0.25-mL straws. However, plasma membrane integrity analysis did not differ between the two straws. Thus, it is possible to conclude that equine sperm cryopreserved in 0.5-mL straws has better sperm kinetics than when stored in 0.25-mL straws. Additionally, it is possible to conclude that automated systems that enable faster freezing rates result in a seminal quality that is similar to the one obtained by the conventional system using Styrofoam boxes. © 2013 Elsevier Inc.

Optically transparent membrane based on bacterial cellulose/ polycaprolactone

Optically transparent membranes from bacterial cellulose (BC)/polycaprolactone (PCL) have been prepared by impregnation of PCL acetone solution into dried BC membranes. UV-Vis measurements showed an increase on transparency in BC/PCL membrane when compared with pristine BC. The good transparency of the BC/PCL can be related to the presence of BC nanofibers associated with deposit of PCL nano-sized spherulites which are smaller than the wavelength of visible light and practically free of light scattering. XRD results show that cellulose type I structure is preserved inside the BC/PCL membrane, while the mechanical properties suggested indicated that PCL acts as a plasticizer for the BC membrane. The novel BC/PCL membrane could be used for preparation of fully biocompatible flexible display and biodegradable food packaging.

Biochemical Profile of Amniotic and Allantoic Fluid During Different Gestational Phases in Mares

Fetal fluids have different vital functions that sustain both pregnancy and normal parturition. The biochemical composition of amniotic fluid during gestation is not well established; thus the purpose of the present study was to determine the biochemical profile of both amniotic and allantoic fluids from mares during initial, mid, and latter third phases of pregnancy. Samples were collected after slaughter, using allantocentesis and amniocentesis. Sixty samples of fetal fluids were analyzed. Alkaline phosphatase (AP), glucose, total protein (TP), urea, creatinine, Ca, chloride (Cl), Na, and K concentrations were measured using commercially available kits. The AP concentration in amniotic fluid was higher than that in allantoic fluid during the three gestational phases (P < .05). There were no differences between glucose mean values of allantoic and those of amniotic fluids (P < .05). However, glucose values were higher in the allantoic fluid in the last trimester of pregnancy. TP was higher in the amniotic fluid than in allantoic fluid (P < .05). Urea values varied among the phases; however, there were no differences between the amniotic and allantoic fluid values (P > .05). Creatinine values were higher in allantoic fluid (P < .05). Na and Cl concentrations were higher in amniotic fluid (P < .05). However, Ca and K concentrations were higher in the allantoic fluid. © 2013 Elsevier Inc. All rights reserved.

Efeitos da membrana amniótica homógena associada ao laser arseneto de gálio-alumínio (λ=660) na reparação de mucosite oral em ratos tratados com 5-fluoruracila: análise histológica e imunohistoquímica

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Rotura prematura de membranas pré-termo e corioamnionite histológica: aspectos da resposta imune inata e repercussões no período neonatal

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Methods for obtaining reabsorbable composites, composites, membrane, scaffold and its uses

The present invention relates to novel methods of obtaining reabsorbable composites, based on bacterial cellulose and collagen, for application in tissue repairing Additionally, the present invention relates to the composites obtained by the methods described herein and their uses.