PURPOSE: The purpose of the study was to coat surgical sutures with a new quaternary ammonium silane (QAS) antimicrobial compound at two different application temperatures and then to evaluate the resulting structural, physical, mechanical, and biological properties.

STUDY DESIGN, SETTING, SAMPLE: In vitro and in vivo studies were conducted using male albino Wistar rats approved by the Joint Ethical Committee of IMU and Postgraduate Medical Institute, Lahore. Only suture samples, coated uniformly with verified presence of the compound and of adequate length were used. Samples which were not coated uniformly and with inadequate length or damaged were excluded.

PREDICTOR VARIABLE: Predictor variables were sutures with and without QAS coatings and different temperatures. Sutures were coated with QAS at 0.5 and 1.0% wt/vol using the dip coating technique and sutures with and without QAS coating were tested at 25 and 40 °C temperatures.

MAIN OUTCOME VARIABLE(S): Outcome variables of structural and physico-mechanical properties of QAS-coated and non-coated sutures were measured using Fourier transform infrared spectroscopy (for structural changes), confocal laser and scanning electron (for diameter changes), and tensile strength/modulus (for mechanical testing). Biologic outcome variables were tested (bacterial viability); macrophage cultures from Wistar rats were tested (M1/M2 polarization detecting IL-6 and IL-10). Macrophage cells were analyzed with CD80+ (M1) and CD163+ (M2). Chemotaxis index was calculated as a ratio of quantitative fluorescence of cells.

COVARIATES: Not applicable.

MATERIAL AND METHODS: Thirty Sprague Dawley rats (3-monthold, 200 to 300 gm) were randomly divided into six groups, namely control (C), 4 weeks diabetes mellitus (DM1), 8 weeks DM (DM2) and three DM1 groups (VD1, VD2, and VD3) who received Vitamin D doses of 0.125, 0.25 and 0.50 μg/kg BW, respectively. After 4 weeks, daily VD was administered intraperitoneally for 30 days. Lung tissues were taken for IL- 6, MCP-1, NFKB and CD68 mRNA expression analysis and paraffin embedding. Immunohistochemical staining against CD68 and MCP-1 was conducted. Data were analysed using one-way ANOVA. p < 0.05 was considered statistically significant.

RESULTS: DM2 group represented significantly higher IL6, MCP1, NFKB and CD68 mRNA expression than Control group (p < 0.05). Meanwhile, VD2 and VD3 groups revealed significantly lower mRNA expression of IL-6, MCP1, NFKB and CD68 than DM2 (p < 0.05). Immunostaining revealed the spreading of MCP1 protein expression in lung tissue along with macrophage infiltration in the DM2 group, which was reduced in the VD2 and the VD3 groups.

MATERIALS AND METHODS: This was a randomised post-testonly study. A total of 28 rats were assigned into four groups: Group 1 is control group (C), samples had bile duct ligation and UDCA monotherapy 20 mg; Group 2, bile duct ligation + UDCA 10 mg + glutathione 10 mg (P1); Group 3, bile duct ligation + UDCA 20 mg + glutathione 15 mg (P2); Group 4, bile duct ligation + UDCA 30 mg + glutathione 20 mg (P3). Serum AST, ALT, ALP activity, total, direct and indirect bilirubin were collected. Shapiro-Wilk test was used for the normality test. All groups' data were compared using Kruskall-Wallis and Mann-Whitney tests.

RESULTS: There was a significant difference in the ALP level in all rats and between the C and P2 groups. ALP level of all groups decreased significantly compared to the control group. Combination therapy group showed lower bilirubin levels. ALT levels significantly differed between the C-P1, P1-P2, and P1-P3 groups.