Biosynthesis of Gold Nanoparticles (AuNPs) by Diopatra claparedii Grube, 1878 (Polychaeta: Onuphidae) and Its Antibacterial Activity

Gold nanoparticles (AuNPs) have gained attention as it possesses outstanding physicochemical properties, and utilised in variety of applications especially in biomedical and pharmaceutical. Majorly, AuNPs are produced by conventional methods (chemical and physical). However, these methods bring several drawbacks such as toxic, hazardous, low yield and non-environmental friendly. Hence, biosynthesis of AuNPs that compliance with ‘greener’ approach becomes vitals. In this study, marine tube worm of Diopatra claparedii (polychaetes) was employed as reducing agent in the biosynthesis of AuNPs. The biosynthesised of AuNPs by D. claparedii extract was successfully prepared under ambient temperature and normal atmospheric conditions. The formation of AuNPS was confirmed by the appearance of surface Plasmon resonance (SPR) bands around 540 to 560 nm characterized by UV-Vis spectroscopy. Scanning electron microscopy (SEM) showed that the AuNPs are mostly in agglomerated spherical like shapes with size ranging from 100 to 400 nm. Meanwhile, transmission electron microscopy (TEM) showed that the particles are in the size range from 25 to 60 nm, also mainly form in spherical like shape. The particle size of AuNPs in a range of 50-100 nm was showed by dynamic light scattering (DLS). Fourier-transform infrared (FTIR) spectrum of D. claparedii extract indicated the existence of several functional groups. Biosynthesised AuNPs also successfully gave inhibition on bacterial growth (Staphyloccus aureus, S. epidermidis, Escheratia coli, Salmonella typhi) through antibacterial assessment.

Comparison of the Patient Diagnostic Yield of Fibre-optic Bronchoscopy with Conventional Tracheal Aspirate

Objective: To know the efficacy of Bronchoalveolar Lavage (BAL) in establishing diagnosis and its impact on overall health status of the patients. Methods: A single center, longitudinal study involving 40 patients aged > 18 years old with septic shock with similar baseline characteristics was conducted. Two study arms, 20 patients in intervention arm - patient with utilization of Bronchoscopy and BAL in aiding diagnosis and 20-patients in conservative- arm without Bronchoscopy were compared in terms of establishing diagnosis primarily and secondarily in terms of length of stay and 30-day mortality. We were able to identify following organisms in BAL sample: Mycobacterium tuberculosis- 4, Acinetobacter baumanii- 3, Pseudomonasaeruginosa- 2, Klebsiella oxytica- 2, E. coli- 2, Streptococcus pneumoniae- 2, Staphyloccus aureus- Results: We were able to identify various infectious agents as mentioned above 16/20 in BAL group compared to 8/20 in conventional arm; neoplasm in 4 out of 20 subjects in BAL group. In 80% of cases, BAL helped in identifying the organisms compared to only 40% in tracheal aspirate group. In addition, six cases in Intervention arm vs. nine cases in conventional arm had more than > 14 days hospital stay with the p-value 0 .492091. Interventional arm had lesser mortality 5 cases vs. 7 cases in Conventional arm with the p-value of 0.490153 which was not statistically significant. Conclusion: We conclude that the diagnostic bronchoscope and related procedures among critically ill patients are helpful in identifying the pathogens and in detecting malignancy.

Antibiotic Resistance in Nosocomial Bacteria Isolated from Infected Wounds of Hospitalized Patients in Czech Republic

Hospitalized patients with wounds face an increased risk of infection with multi-drug-resistant nosocomial bacteria. In this study, samples from almost 10,000 patients from big hospitals in Czech Republic with infected wounds were analyzed for the presence of bacterial pathogens. In 7693 patients (78.8%), bacterial etiological agents were identified. Members of the Enterobacterales (37.1%) and Staphyloccus aureus (21.1%) were the most prevalent pathogens. Staphyloccus aureus showed methicillin resistance in 8.6%. Almost half of the Klebsiella pneumoniae isolates were ESBL-positive and 25.6% of the Enterobacter spp. isolates were AmpC-positive. The third most prevalent Pseudomonas aeruginosa showed resistance to 19–32% of the antipseudomonal antibiotics tested. Based on the results, amoxicillin/clavulanic acid, ampicillin/sulbactam or piperacillin/tazobactam combined with gentamicin can be recommended for antibiotic treatment of infected wounds. Once the etiological agent is identified, the therapy should be adjusted according to the species and its resistance.