Background and Objectives: Blood stream infections cause significant morbidity and mortality in the world. In this study, we aimed at describing the organisms responsible for septicemia in 20062007- and their antimicrobial susceptibility that might lead to proper selection of antimicrobial agents in hospitalized patients with suspected sepsis. Materials and Methods: Microbiology reports of 1753 blood specimens collected from inpatients of a referral hospital in Iran were retrospectively reviewed. Specimen culture, bacterial identification, and disk diffusion susceptibility testing were performed according to The Clinical and Laboratory Standards Institute guidelines. Data were analyzed by SPSS, X² Test and the fisher exact Test.Results: Coagulase-negative Staphylococci accounted for most isolated bacteria (24.61%), in both genders. The second and third most frequent isolated bacteria in adults were staphylococcus aureus and STENOTROPHOMONAS maltophilia, and in children were Klebsiella pneumoniae and S. aureus. Among the all Gram – positive cocci, vancomycin was the most effective agent. The most effective antibiotic varied among the Gram-Negative isolates, for example 95.65% of S. maltophilia were susceptible to co-Trimoxazole, and amikacin were suitable antibiotic in 85.29% of E. coli. Conclusion: As the degree of antibiotic resistance rate for blood stream pathogens is alarming, it is mandatory to monitor the susceptibility of these isolates in order to avoid inappropriate use of antibiotics in hospital wards.

Background: The pandemic caused by the new coronavirus is overwhelming the world. Bacteria and fungi were detected in some cases, which suggested the associations between COVID-19 and bacterial and fungal infections. Objectives: To provide suggestions and treatment opinions by analyzing laboratory data of COVID-19 patients co-infected with bacteria. Methods: We analyzed 63 patients with COVID-19 admitted to the isolation ward of the First Affiliated Hospital of Wenzhou Medical University. COVID-19 was detected using PCR, and bacteria were identified using culture. Patients were divided into two groups, including those with and those without bacterial infections, and differences in hematologic indices between the groups were analyzed. Results: There were 63 patients with median age of 55. 82 years. The average hospital stay was 22. 56 days. Seven patients (11. 11%) had coincident bacterial infections. Detection rates in sputum/alveolar lavage and blood were the highest, 60. 52% and 21. 05%, respectively. Klebsiella pneumoniae, Acinetobacter, and STENOTROPHOMONAS maltophilia were the most common found in 31. 58%, 18. 42%, and 15. 79%, respectively. Interleukin 6 (IL-6) levels were elevated in 84. 13% of patients, while IL-10 levels were elevated in 69. 84%, blood ammonia levels were elevated in 82. 05%, lactate levels were elevated in 75. 41%, and LDH levels were elevated in 69. 84%. There were significant differences between the groups in terms of expression levels of IgG, C4, AST, LDH, IL-6, IL-10, percentage of neutrophils, percentage of lymphocytes, and platelets. Conclusions: For patients with COVID-19 suspected of having bacterial infections, empiric antibiotics should be given to cover K. pneumoniae, Acinetobacter, and S. maltophilia.

Mangroves are the tidal forest existing in the intertidal zone and usually considered as the special marine ecosystem. In the present study, 452 actinomycetes were recovered from nine diferent sites at Maowei Sea Mangrove Reserve in Qinzhou (Guangxi province, China). Among them, Seventy-four strains were purified for 16s RNA gene sequencing and further characterization. The results indicated that the majority of isolates belonged to the genera Streptomyces, including 17 species. Streptomyces sanyensis was the dominant species (31.1%), followed by Streptomyces griseorubens (17.5%), Streptomyces viridobrunneus (10.8%) and other Streptomyces species. Only one rare actinomycete, STENOTROPHOMONAS was discovered. The isolation of actinomycetes was obviously related to the type of soil and edaphic conditions. Rhizosphere-associated soils gave almost 62.2% actinomycete isolates, nearly twice as many as the non-rhizosphere-associated soils. In addition, 20 actinomycete strains (27%) presented varied antibacterial activities towards four tested organisms, including two drug-resistant clinical strains (MRSA and VRE), while some species of Streptomyces like S.sanyensis, S.viridobrunneus, S.tanashiensis, S.parvus, S.flavotricini, and S.parvulus exhibited remarkable cytotoxic activities. Further bioinformatical analysis of these 29 bioactive strains for secondary metabolites biosynthetic machineries revealed that nonribosomal peptide synthetase (NRPS) was detected in 20 isolates (68.9%), whereas type-I polyketide synthase (PKS-I) and type- II polyketide synthase (PKS-II) were detected in 16 and all of the 29 strains, respectively. Hence, our work demonstrated that actinomycetes from mangroves in Maowei Sea Mangrove Reservewere fascinating reservoirs for antibacterial and antitumor natural products discovery

The biosorption of copper (II) from aqueous solution using different bacterial strains was studied. Copper-biosorbing bacteria were isolated from tannery effluent collected from Borg Al-Arab, Alexandria, Egypt. These isolates displayed different degrees of copper biosorption under aerobic conditions. Based on 16S rDNA gene sequence analysis, three of them (S2, S5 and S7) were identified as Chryseobacterium sp., Enterobacter sp. And STENOTROPHOMONAS sp., respectively. Initial copper (II) ion concentrations from 25-250 mg/L at constant temperature 30°C were studied. The residual copper (II) concentration and its toxicity effect in solution were determined using atomic absorption spectrophotometer and bioluminescent bioreporter. The bioluminescence inhibition of strain (S5) reached to 91.4 % as compared with the strain (S7) reached to 83.3 % at 225 mg/L of copper ion where the maximum biosorption efficiency for S5 and S7 were 71 % and 70.1% correspondingly using atomic absorption. The bioluminescent bioreporter was proved to be fast and accurate technique for measurement the toxicity effect of residual copper (II) in solution.

Background and Objectives: Non-fementer gram-negative bacilli (NFGB) are ubiquitous pathogen that has emerged as a major cause of health care associated infections. The aim of this study was to determine the prevalence and antimicrobial susceptibility of NFGB in an Iranian hospital.Materials and Methods: From July 2005 to November 2006 a total of 257 strains of NFGB including 109 (42.41%) strains of Pseudomonas aeruoginosa, 88 (34.24%) strains of Acinetobacter baumannii, 48 (18.67%) stains of STENOTROPHOMONAS maltophilia and 12 (4.66%) strains of Burkholderia cepacia were isolated from clinical specimens taken from patients hospitalized in Milad Hospitsl, Tehran, Iran. Conventional bacteriological methods were used for identification and susceptibility testing of NFGB. Susceptibility testing was performed by method as recommended by Clinical Laboratory Standard Institute (CLSI). Data were analyzed using SPSS 11.5 for Windows (SPSS Inc., Chicago, IL).Results: A total of 257 non-duplicating of NFGB strains were isolated from 234 hospitalized patients. The most effective antibiotic against P. aeruginosa and A. baumannii was imipenem followed by tobramycin. Fluoroquinolones had moderate activity against P. aerugunosa. Most isolates of A.baumannii were multi-drug resistant. Susceptibility of S. maltophila to ticarcillinclavuanic, ofloxacin and ceftazidim was 96%, 94% and 81%, respectively. Thirty three percent of this bacterium isolates were resistant to co-trimoxazole.Conclusion: In our study, imipenem was the most effective antibiotic against P. aeruginosa and A. baummannii isolates. Previous history use of antibiotics, longer duration of hospital stay and mechanical ventilation were the major risk factors for resistance acquisition in NFGB especially in P. aeruginosa and A. baumannii.

Background: Ventilator-associated pneumonia (VAP) is a common nosocomial infection among hospitalized patients who have undergone intubation and mechanical ventilation for more than 48 hours. Patients admitted to the intensive care unit (ICU) are at risk of developing life-threatening VAP due to specific conditions, especially with Gram-negative pathogens with advanced drug resistance. Hereby, the control of these agents and its monitoring is of particular importance. In this study, the pattern of antibiotic resistance of Gram-negative bacteria isolated from tracheal culture of patients with VAP investigated in ICU of Imam Khomeini Hospital of Ahwaz. Materials and Methods: In this cross-sectional study, tracheal samples were collected during April 2016 to April 2017 from patients who were on mechanical ventilation in ICU of Imam Khomeini Hospital in Ahwaz, Khuzestan province, southwest of Iran. After isolation, bacterial strains were identified using biochemical tests. Then, antimicrobial resistance pattern of these isolates investigated using standard disc diffusion according to clinical and laboratory standards institute 2016 (CLSI 2016) guidelines. Results: A total of 111 bacterial isolates were identified which were as following; Acinetobacter baumannii, Pseudomonas aeruginosa, Klebsiella pneumoniae, Escherichia coli, STENOTROPHOMONAS maltophilia, and Serratia marcescens, with prevalence of 54%, 19. 8%, 14. 4%, 6. 4%, 4. 5%, and 0. 9%, respectively. Antibiotic susceptibility test of isolates showed that almost all isolates had high resistance to treatment antibiotics and were multi-drug resistance (MDR). The A. baumannii isolates were resistant to ciprofloxacin and piperacillin-tazobactam, but ampicillin-tazobactam had a good effect. Conclusion: The results of this study showed that patients admitted to ICU due to their conditions of treatment are more likely to develop VAP by Gram-negative pathogens. The empirical treatment of VAP due to predominant bacterial causes and emerging drug resistance has become more challenging. It requires to use of multidrug regimens for routine clinical practice. It should be noted that in order to appropriate antimicrobial therapy, precise and correct diagnosis is very important.