ABSTRACT
The use of natural supplies is a resource to mimic an original extracellular matrix that allows for migration, proliferation, and cellular organization. Chitosan from Brazilian Atlantic Ocean had low protein, minerals percentage and excellent antibacterial activity. The aim of this study was to evaluate and to compare the effectiveness of different types of acids as solvents with Brazilian chitosan-membrane in the healing process of skin lesions. Experimental full-thickness 2 × 2 cm wounds were created on the dorsum skin of Wistar rats. The applied different treatments were saline, collagenase®, microcrystalline chitosan salt membrane (MCSM), microcrystalline chitosan acetic acid membrane (MCAAM), and microcrystalline chitosan hydrochloric acid membrane (MCHAM). The wound repairs were measured morphologically and histologically on days 0, 3, 7, 10, and 14. The exudate formation and the final wound contractions were similar in all of the groups. There were mild exudations in the groups with chitosan-membranes, despite the formation of crust under the membrane. This configured a serum hematic aspect, but there was no impact on the healing process. The MCHAM group had more favorable aspects that histologically showed the healing phases. A significant migration of neutrophils and macrophages seen by myeloperoxidade and Beta-N-Acetylglucosaminidase activities was evident in the chitosan groups, MCHAM and MCSM, respectively. Furthermore, the MCHAM group created its histological arrangement in a dense and more consistent manner.
Subject(s)
Biocompatible Materials/pharmacology , Chitosan/pharmacology , Wound Healing/drug effects , Acetylglucosaminidase/metabolism , Animals , Collagen/metabolism , Inflammation/pathology , Male , Peroxidase/metabolism , Rats, WistarABSTRACT
INTRODUCTION: The susceptibility to pulmonary tuberculosis (TB) is multifactorial, thus genetic factors such as HLA and immunoglobulins-like killer receptors (KIR) could be predisposed to the development of the disease. Aim To evaluate whether any HLA classi allele and its combination with KIR could be related to the development of TB in the Wichi Amerindian community in north-eastern Argentina. METHODS: A cohort study was conducted that included 18 families, 35 individuals affected with TB, 84 cohabiting families, and 63 controls of the same ethnic group. A and B loci of HLA classi were typed by generic PCR followed by reverse hybridization (Dynal), locus C by PCR-SSOP. KIR receptors were studied using sequence specific PCR. RESULTS: There was a highly significant association with allele B*35:19/47 in TB vs. household contacts [Pc=0.0051] and vs. controls [Pc=0.0033], and with allele HLA-C*03 in TB vs. household contacts [Pc=0.014] and vs. controls [Pc=0.0033]. KIR receptors had shown increased KIR2DL3/KIR2DL3 frequency in combination with the C1 group of HLA-C (P=.018). HLA-C*03 belongs to C1 group, and this combination could have a strong inhibitory action on the infected cell. CONCLUSION: HLA-B35:19/47-C*03 haplotype could be a susceptibility factor to TB and KIR2DL3-HLA-C1 combination have an inhibitory capacity on NK cells, and might contribute to the course of the infection by Mycobacterium tuberculosis.