Features of leukocytes’ apoptosis and emoxypine succinate efficacy in case of combined trauma of the chest and both thighs in rats

Objective: This study aims to establish features of blood leukocytes’ apoptosis and substantiate the efficacy of emoxypine succinate applying in case of combined trauma of the chest and both thighs in rats. Materials and Methods: Analysis of cell samples to determine reactive oxygen species was evaluated by the flow laser cytometry method, using 2.7-dichlorodihydrofluorescein diacetate (Sigma Aldrich, Germany). The number of leukocytes with low mitochondrial transmembrane potential was evaluated by the flow laser cytometry method, using a kit of reagents «MitoScreen» («BD Pharmingen», USA). The number of apoptotic leukocytes was evaluated by the flow laser cytometry method, using a kit of reagents “ANNEXIN V FITC” (“Beckman Coulter”, USA). Emoxypine succinate to animals was injected intraperitoneally 1 time per day during 14 days from the first day of experiment in the dosage of 40 mg/kg. Results and Discussion: It was established the progressive, statistically significant increasing of Annexin V- positive cells percentage from the first day of the combined trauma of the chest and both thighs in rats with the highest values within 7-14 days of observation. On 28 day of experiment the reduction of apoptotic white blood cells percentage by 7.7% than the findings on 14 day was observed, but it remained 33.3% higher than control. The analysis of data in case of emoxypine succinate applying indicates that production of reactive oxygen species by leukocytes began to decline after 3 days of experiment and continued to decrease with maximum of action on 7 day. On 28 day of experiment the production of reactive oxygen species by leukocytes has decreased by 39.8 %; the percentage of leukocytes with low transmembrane potential has decreased by 34.6 % vs rats without medical treatment. At the same time the dynamics of FITC Annexin V- positive leukocytes changes in case of combined trauma of the chest and both thighs in rats and emoxypine succinate applying on 28 day of experiment has decreased by 16.7 % vs rats without medical treatment. Conclusion: One of important signaling pathways of apoptosis triggering in case of experimental combined trauma of the chest and both thighs is reactive oxygen species overproduction and disruption of the mitochondrial inner membrane due to the decreasing of transmembrane potential in 3-7 days of observation. Emoxypine succinate applying in post-traumatic period has a positive effect, characterized by decreasing of the production of reactive oxygen species, the percentage of leukocyte with low mitochondrial transmembrane potential and the percentage of FITC Annexin V- positive cells of leukocyte suspension. But the dynamics of FITC Annexin V- positive leukocytes changes leads us to believe that in the initiation and implementation of cell death in case of combined trauma apart mitochondrial, there are other mechanisms. Bangladesh Journal of Medical Science Vol.18(2) 2019 p.244-251

Rapid Staining and Enumeration of Small Numbers of Total Bacteria in Water by Solid-Phase Laser Cytometry

ABSTRACT The nucleic acid stain SYBR Green I was evaluated for use with solid-phase laser cytometry to obtain total bacterial cell counts from several water sources with small bacterial numbers. Results were obtained within 30 min and exceeded or equaled counts on R2A agar plates incubated for 14 days at room temperature.

Sensitive Detection of Escherichia coliO157:H7 in Food and Water by Immunomagnetic Separation and Solid-Phase Laser Cytometry

ABSTRACT Rapid, direct methods are needed to assess active bacterial populations in water and foods. Our objective was to determine the efficiency of bacterial detection by immunomagnetic separation (IMS) and the compatibility of IMS with cyanoditolyl tetrazolium chloride (CTC) incubation to determine respiratory activity, using the pathogenEscherichia coli O157:H7. Counterstaining with a specific fluorescein-conjugated anti-O157 antibody (FAb) following CTC incubation was used to allow confirmation and visualization of bacteria by epifluorescence microscopy. Broth-grown E. coli O157:H7 was used to inoculate fresh ground beef (<17% fat), sterile 0.1% peptone, or water. Inoculated meat was diluted and homogenized in a stomacher and then incubated with paramagnetic beads coated with anti-O157 specific antibody. After IMS, cells with magnetic beads attached were stained with CTC and then an anti-O157 antibody-fluorescein isothiocyanate conjugate and filtered for microscopic enumeration or solid-phase laser cytometry. Enumeration by laser scanning permitted detection of ca. 10 CFU/g of ground beef or <10 CFU/ml of liquid sample. With inoculated meat, the regression results for log-transformed respiring FAb-positive counts of cells recovered on beads versus sorbitol-negative plate counts in the inoculum were as follows: intercept = 1.06, slope = 0.89, andr 2 = 0.95 (n = 13). The corresponding results for inoculated peptone were as follows: intercept = 0.67, slope = 0.88, andr 2 = 0.98 (n = 24). Recovery of target bacteria on beads by the IMS-CTC-FAb method, compared with recovery by sorbitol MacConkey agar plating, yielded greater numbers (beef, 6.0 times; peptone, 3.0 times; water, 2.4 times). Thus, within 5 to 7 h, the IMS-CTC-FAb method detected greater numbers of E. coli O157 cells than were detected by plating. The results show that the IMS-CTC-FAb technique with enumeration by either fluorescence microscopy or solid-phase laser scanning cytometry gave results that compared favorably with plating following IMS.