Particle recognition by haemocytes from the colonial ascidianBotrylloides leachii: Evidence that theB. leachii HA-2 agglutinin is opsonic

Summary Haemocytes from the ascidianBotrylloides leachii were observed in vivo to phagocytose sheep erythrocytes. The possibility that a sheep erythrocyte agglutinin (the HA-2 agglutinin) previously purified fromB. leachii haemolymph functions as a recognition molecule for the phagocytosis of these erythrocytes was investigated. Untreated sheep erythrocytes were found to adhere toB. leachii haemocytes in vitro. Adherence appeared to be mediated by the HA-2 agglutinin, as evidenced by the inhibition of adhesion by lactose (which is a specific inhibitor of the HA-2 agglutinin) and by an anti-HA-2 IgG preparation. Immunofluorescence studies indicated that HA-2 molecules secreted by the haemocytes bound to unsensitised erythrocytes, causing them to adhere to haemocytes. No HA-2 agglutinin could be detected on the surface of the haemocytes in the absence of erythrocytes but receptors for the agglutinin were detected. The results suggest that the HA-2 agglutinin can function as a recognition molecule for sheep erythrocytes and other particles bearing the appropriate carbohydrate moieties on their surfaces. At least one of two other lectins purified from haemolymph (HA-1 and LBP-3) was detected by immunofluorescence on the surface of haemocytes. The function(2) of these latter molecules, neither of which binds to sheep erythrocytes, is not known.     

Schiff Base Derivatives of 4-Aminoantipyrine as Promising Molecules: Synthesis,Structural Characterization,and Biological Activities

Russian Journal of Bioorganic Chemistry - In this study, some Schiff bases derived from 4-aminoantipyrine (4-AAP) (VI–X) were synthesized, characterized by elemental analysis (C, H, N) and...     

Lesions in thighs from hunted Brown Hares (<Emphasis Type="Italic">Lepus europaeus</Emphasis>) and microflora under vacuum-packaging storage

In two surveys, thighs of a total of 137 hunted hares were tested for the presence of intramuscular shots and femur fractures, which were detected in 42.7% and 29.2% of 274 thighs, respectively. Femur fractures were significantly associated with the presence of intramuscular shots. In the second survey (46 hares), 92 thighs were grouped into three categories, “A” (no fractures, no intramuscular shot), “B” (one intramuscular shot), and “C” (multiple shots and hematoma), with 49.0%, 33.6%, and 17.4%, respectively. Category “C” was found unfit for human consumption. During 7-day storage of vacuum-packed “A” and “B” thighs, total aerobic counts increased from initially 3.3 ± 0.3 (mean ± SD) and 4.1 ± 0.6 log cfu/g by ca. 2 log units when stored at 3–4°C, whereas the increase was clearly <1 log unit at 0°C. In comparison to temperature, differences between “A” and “B” category were less pronounced. Similar dynamics were observed for Enterobacteriaceae. In all categories, muscle pH values (mean = 5.83) were similar. It is concluded that storage at temperatures of ca. 4°C, although in compliance with EU legislation, does not afford keeping microbial contaminants in check, and thus will not preserve microbiological quality of vacuum-packed hare meat.     

Fimbria targeting superparamagnetic iron oxide nanoparticles enhance the antimicrobial and antibiofilm activity of ciprofloxacin against quinolone-resistant E. coli

High quinolone resistance of Escherichia coli limits the therapy options for urinary tract infection (UTI). In response to the urgent need for efficient treatment of multidrug-resistant infections, we designed a fimbriae targeting superparamagnetic iron oxide nanoparticle (SPION) delivering ciprofloxacin to ciprofloxacin-resistant E. coli. Bovine serum albumin (BSA) conjugated poly(acrylic acid) (PAA) coated SPIONs (BSA@PAA@SPION) were developed for encapsulation of ciprofloxacin and the nanoparticles were tagged with 4-aminophenyl-α-D-mannopyrannoside (mannoside, Man) to target E. coli fimbriae. Ciprofloxacin-loaded mannoside tagged nanoparticles (Cip-Man-BSA@PAA@SPION) provided high antibacterial activity (97.1 and 97.5%, respectively) with a dose of 32 μg/mL ciprofloxacin against two ciprofloxacin-resistant E. coli isolates. Furthermore, a strong biofilm inhibition (86.9% and 98.5%, respectively) was achieved in the isolates at a dose 16 and 8 times lower than the minimum biofilm eradication concentration (MBEC) of ciprofloxacin. Weaker growth inhibition was observed with untargeted nanoparticles, Cip-BSA@PAA@SPIONs, confirming that targeting E. coli fimbria with mannoside-tagged nanoparticles increases the ciprofloxacin efficiency to treat ciprofloxacin-resistant E. coli. Enhanced killing activity against ciprofloxacin-resistant E. coli planktonic cells and strong growth inhibition of their biofilms suggest that Cip-Man-BSA@PAA@SPION system might be an alternative and/or complementary therapeutic option for the treatment of quinolone-resistant E. coli infections.