Behaviour of Incorporation of Bacteria in Concrete

The life of the healing in concrete is many years old and when the study was done on this, outcomes were coinciding with the auto-genus healing process which was capable to heal the micro cracks inside cementitious based materials and hereafter research led to the study of autonomous healing. In the autonomous healing process, the main aim was to fill the cracks and heal the fracture at the macro level. This was possible with the help of bacteria that were embedded in the cementitious based material with different technologies and methods. In this paper, Enterobacter species and Cohnii bacteria were incorporated into concrete. The behaviour of bacterial concrete was investigated in terms of compressive, tensile, flexural strength and ultrasonic pulse velocity. It observed that the compressive strength of concrete was increased by 11.5%, flexural strength increased by 11.9%, tensile strength increased by 12.8% with the replacement of Cohnii bacteria as compare to conventional concrete. These bacteria have been proved a positive approach to the healing process in cementitious based material. Also, the important criterion has been studied which is essential when dealing with the autonomous healing process. Both the bacteria generate the calcite that helps to fill the concrete crack and voids if water come in to contact.

Bacterial and Fungal Co-Infections among ICU COVID-19 Hospitalized Patients in a Palestinian Hospital: Incidence and Antimicrobial Stewardship

Diagnosis of co-infections with multiple pathogens among hospitalized COVID-19 patients can be jointly challenging and very essential for appropriate treatment, shortening hospital stay and preventing antimicrobial resistance. This study proposes to investigate the burden of bacterial and fungal co-infections outcomes on COVID-19 patients. It is a single centre cross-sectional study of hospitalized COVID-19 patients at Beit-Jala hospital in Palestine. The study included 321 hospitalized patients admitted to the ICU between June 2020 and March 2021 aged ≥ 20 years, with a confirmed diagnosis of COVID-19 via RT-PCR conducted on a nasopharyngeal swab. The patient’s information was gathered using graded data forms from electronic medical reports. The diagnosis of bacterial and fungal infection was proved through the patient’s clinical presentation and positive blood or sputum culture results. All cases had received empirical antimicrobial therapy before the ICU admission, and different regimens during the ICU stay. The rate of bacterial co-infection was 51.1%, mainly from gram-negative isolates (Enterobacter species and K.pneumoniae). The rate of fungal co-infection caused by A.fumigatus was 48.9%, and the mortality rate was 8.1%. However, it is unclear if it had been attributed to SARS-CoV-2 or coincidental.

Re-examining the association of AmpC variants with Enterobacter species in the context of updated taxonomy

We performed whole genome sequencing for 17 Enterobacter clinical strains and analyzed all available Enterobacter genomes and its closely-related genera (n=3,389) from NCBI. The exact origin of plasmid-borne bla CMH and bla MIR genes is Enterobacter cloacae and Enterobacter roggenkampii , respectively, while plasmid-borne bla ACT genes originated from multiple other Enterobacter species including Enterobacter xiangfangensis , Enterobacter hoffmannii , and Enterobacter asburiae , Enterobacter ludwigii , and Enterobacter kobei . The genus of Enterobacter represents a large reservoir of plasmid-borne AmpC β-lactamase.

Isolation and Molecular Characterization of Klebsiella And Enterobacter Species Recovered in Sunflower Seed Agar from Cases Resembling Respiratory Cryptococcosis

Respiratory cryptococcosis caused by Cryptococcus species can present with symptoms indistinguishable from bacterial or viral etiology. Cryptococcus species produce typical colonial features on Sunflower Seed Agar (SSA), which aids in rapid diagnoses of cryptococcosis. In studying respiratory cryptococcosis, we observed bacterial growths on SSA that resembled Cryptococcus species in colonial characteristics. This study aimed at identifying and characterizing those bacterial isolates for documentation. Sputum samples were collected from 201 patients with symptoms suggestive of respiratory cryptococcosis. The samples were inoculated onto SSA, incubated at 37oC for two weeks. Suspected colonies were further evaluated. Of the samples, none yielded Cryptococcus species, although a total of twenty Cryptococcus-resembling bacterial colonies were encountered and isolated. Eight of the isolates could not amplify by PCR techniques. The other twelve were identified as follows: Klebsiella pneumonia (8 or 67%), Klebsiella ozaneae (3 or 25%), and Enterobacter ludwigii (1 or 8%). All isolates were susceptible to Ertapenem, Meropenem, and Fosfomycin but resistant to ampicillin. Results show that Klebsiella and Enterobacter pneumonia-like illnesses can be misidentified as cryptococcosis using SSA. Reliance on microscopic rather than macroscopic, colonial features on SSA will prevent misdiagnosis.

Risk Factors for and Mechanisms of COlistin Resistance Among Enterobacterales: Getting at the CORE of the Issue

Background Despite the recent emergence of plasmid-mediated colistin resistance, the epidemiology and mechanisms of colistin-resistant Enterobacterales (CORE) infections remain poorly understood. Methods A case-case-control study was conducted utilizing routine clinical isolates obtained at a single tertiary health system in Ann Arbor, MI. Patients with CORE isolates from January 1st 2016 to March 31st 2017 were matched 1:1 with patients with colistin-susceptible Enterobacterales (COSE) and uninfected controls. Multivariable logistic regression was used to compare clinical and microbiologic features of patients with CORE and COSE to controls. A subset of available CORE isolates underwent whole genome sequencing to identify putative colistin resistance genes. Results Of 16,373 tested clinical isolates, 166 (0.99%) were colistin-resistant, representing 103 unique patients. Among 103 CORE isolates, 103 COSE isolates, and 102 uninfected controls, antibiotic exposure in the antecedent 90 days and age > 55 years were predictors of both CORE and COSE. Of 33 isolates that underwent WGS, a large variety of mutations associated with colistin resistance were identified, including 4 mcr-1/mcr-1.1 genes and 4 pmrA/B mutations among 9 Escherichia coli isolates; 5 mgrB and 3 PmrA mutations among 8 Klebsiella pneumoniae isolates. Genetic mutations found in Enterobacter species were not associated with known phenotypic colistin resistance. Conclusions Increased age and prior antibiotic receipt were associated with increased risk for patients with CORE, and for patients with COSE. Mcr-1, pmrA/B, and mgrB were the predominant colistin resistance-associated mutations identified among E. coli and K. pneumoniae, respectively. Mechanisms of colistin resistance among Enterobacter species could not be determined.

Animal Models in the Evaluation of the Effectiveness of Phage Therapy for Infections Caused by Gram-Negative Bacteria from the ESKAPE Group and the Reliability of Its Use in Humans

The authors emphasize how extremely important it is to highlight the role played by animal models in an attempt to determine possible phage interactions with the organism into which it was introduced as well as to determine the safety and effectiveness of phage therapy in vivo taking into account the individual conditions of a given organism and its physiology. Animal models in which phages are used make it possible, among other things, to evaluate the effective therapeutic dose and to choose the possible route of phage administration depending on the type of infection developed. These results cannot be applied in detail to the human body, but the knowledge gained from animal experiments is invaluable and very helpful. We would like to highlight how useful animal models may be for the possible effectiveness evaluation of phage therapy in the case of infections caused by gram-negative bacteria from the ESKAPE (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, Enterobacter species) group of pathogens. In this review, we focus specifically on the data from the last few years.

Emerging carbapenem resistance in ESKAPE organisms in sub-Saharan Africa and the way forward

The epidemiology of Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter species (ESKAPE) and their role in the development and spread of multidrug resistance (MDR) is not well characterized in sub-Saharan Africa (SSA). Carbapenems possess a broad spectrum of activity and are often reserved for the treatment of MDR infections in developed countries. However, the emergence of carbapenem resistance is increasingly being reported and therefore presents a significant public health threat. Although carbapenems are generally unavailable in African hospitals due to high cost, a small number of studies have reported the occurrence of carbapenem-resistant bacteria (CRB) in SSA. This, therefore, shows that carbapenem resistance (CR) is emerging in Africa. Thus, there is a critical need for deploying robust national and regional multidisciplinary, collaborative, and regulatory approaches aiming at elucidating the epidemiology of CR, its burden on the health care system, and strategies for compacting the development and spread of CR. This report hopes to highlight the epidemiology of carbapenem resistance and the main drivers of antibiotic resistance in SSA and proposes future strategies that can be used to combat the emergence of carbapenem resistance in the region

Isolation and Characterization of Streptomycetes with Potential to Decompose Organic Compounds During Bioremediation of Arable Soil

The study has an objective of isolating and characterizing suspected Streptomycetes with the potential to decompose organic compounds in arable soil. The isolates were grown on a culture media and a total of 61 slopes were inoculated and labeled using the following characterization tests: catalase test, gram staining, oxidase test, motility test, and oxidative-fermentative test. After characterization tests, data generated in the laboratory were analyzed and the study showed that isolates A2 (c, e), B2 (c), C1 (b), C2 (a), D1 (e) and D2 (d) were suspected to be Streptomycetes species. Isolates D1 (d) and D2 (b) were suspected to be Escherichia coli while isolates A1 (a), B2 (a, b) and D1 (a) were suspected to be Bacillus species. Isolates A1 (b), C1 (a), D1 (c), D2 (e) were suspected to be Pseudomonas species. Further identification showed that isolates A2 (d) and B1 (b) could be Enterobacter species while isolates A2 (a, b) were suspected to be Klebsiella species. The study tentatively identified Streptomycetes species; Escherichia coli; Bacillus species; Enterobacter species; Pseudomonas species and Klebsiella species. The suspected Streptomycetes identified were considered as potential organic matter decomposers in arable soil.