A Rapid and Sensitive Detection Method for Pseudomonas aeruginosa Using Visualized Recombinase Polymerase Amplification and Lateral Flow Strip Technology

Pseudomonas aeruginosa is a common opportunistic pathogen that causes acute nosocomial necrotizing pneumonia and is the predominant source of chronic lung infections in patients with the genetic disorder cystic fibrosis. Early diagnosis in infected patients and monitoring P. aeruginosa contamination is therefore of great importance in controlling disease spread and development with timely drugs intervention treatment and cut off infection source. Traditional culture-biochemical methods are time consuming and highly dependent on technicians and expensive instruments. To address these challenges, the present study aimed to develop a rapid, sensitive, and specific, on-site detection method for P. aeruginosa based on recombinase polymerase amplification (RPA) combined with lateral flow strip (LFS) technology. The experimental process included screening and modification of primer and probe sets targeting the unique virulence gene elastase B (lasB); specificity detection in 29 strains of P. aeruginosa and 23 closely-related pathogenic bacteria; sensitivity measurements with gradient-diluted P. aeruginosa genomic DNA and probit regression analysis; and clinical application evaluation using 574 patients samples and calculating coincidence rate and kappa index value in comparison with the culture-biochemical method. The P. aeruginosa RPA-LFS assay could complete the amplification process at 37°C constant temperature within 30 min and results could be visualized by the naked eye within 10 min on LFS. The assay displayed high sensitivity with a limit of detection of 3.05 CFU/reaction. It also demonstrated high specificity by showing no cross reaction with other pathogenic bacteria, and rapidness by being completed in less than an hour. Furthermore, when used with clinical samples, the assay had a coincidence rate of 98.26% with the culture-biochemical method and a kappa index value of 0.9433. These data indicate that the RPA-LFS assay represents a major improvement for P. aeruginosa detection, especially in resource-limited areas.

Identification of Micro-organisms (Parasites and Bacteria) which are Potential as Pathogenic Agent in Glass Eel of Anguilla spp. at the Eel Capture Location, Sukabumi, West Java

Eel (Anguilla sp.) is one of the important commercial fish in some countries particularly in East Asian countries such as Japan, South Korea, China, and Taiwan. The need of eel fry or frequently called as glass eel still relies on the natural capture. The issue of natural captured fish is the high level of bacterial infections and diseases. The dependence of glass eel from the nature provides an indication of infections of parasites and bacteria in glass eel. The existence of parasites and bacteria as microorganisms which are potential as pathogenic agents in the cycle of eel culture can be a serious obstacle, so that the glass eel handling needs a particular attention since the capturing proses from the nature. Therefore, identification of parasites and bacteria in the capture location of glass eel was necessarily conducted in Pelabuhan Ratu Bay, Sukabumi, West Java. The glass eel sampling was conducted in May-June 2019, in 3 locations of estuary with the highest capture yield namely Cimandiri River, Cikaso River and Cibuni River. The number of samples taken were 30 eels at each river location with 2 replicates, so that the total eel samples which were taken were 180 eels. Identification of parasites was conducted by examination of ectoparasite and endoparasite and dentification of bacteria was conducted by conventional method (biochemical method). Based on the result of identification, there was no parasite found in the glass eel samples, while bacteria found as many as 12 species and 3 dominant species namely Listeria sp. found in 40 eel samples with prevalence of 22.2%, Aeromonas hydrophila found in 28 eel samples with prevalence of 15.6%, and Staphylococcus spp. found in 22 eel samples with prevalence of 12.2%.

Epidemiological Profile and Detection of Resistance Genes in Bloodstream Infection in Cancer Patients: High Occurrence of Metallo-β-lactamases in Enterobacteriales

Bloodstream infections remain one of the most common major complications in cancer patients. The aim of the study was to describe the etiology, phenotypic and molecular epidemiology of ICS isolates from cancer patients. Method: identification and the resistance profile were carried out using the automated biochemical method Vitek 2®. The presence and genes resistant to carbapenemases blaIMP, blaVIM, blaGIM, blaSIM, blaSPM, blaKPC, blaNDM, genes oxacilinase blaOXA-48, blaOXA-58, and the presence of ESBL genes blaSHV, blaCTX, blaTEM for Gram-negatives, as well as, mecA, vanA and vanB for Gram-positives were investigated in blood culture isolates. Result: Escherichia coli and Klebsiella pneumoniae were the most frequent pathogens. The serine-β-lactamase gene blaOXA-48 was the most frequent, followed by MβL blaSIM. blaTEM and blaCTX were the most common among ESBL. The mecA and vanA genes were found in Staphylococcus spp. and Enterococcus faecium, respectively. Candida spp showed high resistance to voriconazole and fluconazole. Conclusion: measures to prevent and control the spread of resistance genes are essential to reduce the risks of morbidity and mortality.

Isolation and identification of bacteria and parasites in glass eel (Anguilla spp.)

The disease is the main agent that causes mortality of fish, especially during seed stages. The research aimed to find out bacteria and parasitic speciesin glass eel, Anguilla spp. Bacterial identification was carried out by a biochemical method. The prevalence of bacterial species was calculated using the El-Gohary et al. (2020) formula, while the results of bacterial identification from glass eel were Aeromonas spp., Vibrio spp., Enterococcus spp., Staphylococcus spp., Planococcus spp., Lactobacillus spp., Listeria spp., Citrbacterfreundii, Neisseria spp., Pseudomonas aeruginosa, Kurthia spp., Streptococcus spp., and Corynebacterium spp. It was found that the five highest prevalence rate was for Listeria spp. (39.64%), followed by Aeromonas spp. (26.13%), Staphylococcus spp. (16.22%), Corynebacterium spp. (5.41%), Lactobacillus spp. (2.70%), and the lowest prevalence rate was Streptococcus spp. (0.90%). The type of parasitic pathogen obtained was Trichodina spp. (2,70%), Dactylogyrus spp. (2,70%) and Gyrodactylus spp. (2,70%). Bacterial and parasites identified in glass eels need further verification on the epizootiology characteristic of each pathogenic agent.

Resource-saving technology for dewatering and decontamination of activated sludge

The authors of the article consider the problem of the formation of huge volumes of liquid toxic activated sludge in the biochemical method of the residential area wastewater decontamination. At present, there are no effective technical solutions and technologies in terms of eliminating the negative impact of activated sludge on environmental components. The article examines the technologies that allow to involve activated sludges in reuse and use them as fertilizers in agriculture. A resource-saving biotechnology for activated sludge dewatering and decontamination from ecotoxicants has been developed. The results of the study confirm the effectiveness of the process of heavy metal extraction from activated sludge.

Diagnosis of helicobacter pylori infection: problems and prospects

(HP) infection was performed using invasive and non-invasive methods. The study group consisted of 95 patients with dyspepsia. HP infection was detected in 47 patients (49.4 %). The expediency of using a set of diagnostic methods for detecting HP (PCR, immunochromatographic, bacteriological and method for determining urease activity) is proved. Most often (100 %) in patients HP infection was detected in biopsies using the PCR method. Somewhat less frequently it was detected when examining biopsies with an invasive biochemical method (AMA RUT Reader) (82 %) and fecal immunochromatographic method (83 %). Despite the fact that helicobacteriosis was detected bacteriologically in a small number of patients (24 %), this method is of particular value, since it allows you to assess the sensitivity to antimicrobial drugs and probiotics, and does not give false positive results.

Metabolomics in Lipoid Proteinosis

Background: Lipoid proteinosis (LP) is an autosomal recessive transfer lysosomal storage disease that is characterized by the accumulation of hyalin substance in the mucous membranes, skin, internal organs, and brain. Thus far, no biochemical diagnostic method has been identified. Objective: The aim of this study was to determine the carnitine and acylcarnitine metabolic profiles of LP patients and to examine the potential of LC-MS/MS as a new biochemical method for the identification of biochemical markers. Methods: In this study, 27 carnitine and acylcarnitine esters were measured with LCMS/ MS in serum samples taken from 14 healthy control subjects and 14 patients. The patients, who presented at the Skin and Venereal Diseases Polyclinic, were diagnosed with LP on the basis of clinical, radiological, and histopathological examinations. Results: The results of the study showed that the C0 (free carnitine) C3, C4, C4:DC, C5DC, C6, C8, C14:1, C14:2, C16, and C18 acylcarnitines were statistically significantly reduced in the LP patients (p < 0.05, p < 0.01). Conclusion: It was concluded that the application of carnitine profile screening, an inexpensive, rapid, and reliable method, as a supporting laboratory test could make a contribution to the differential diagnosis for individuals with suspected LP.

Habitats Characteristic and the Resistance Status of Aedes sp. Larvae in the Endemic Areas of Dengue Haemorrhagic Fever in Sewon Subdistrict, Bantul Regency, Special Region of Yogyakarta

Dengue Hemorrhagic Fever (DHF) is caused by Dengue Virus and transmitted by female Aedes mosquito which spread almost all over the world. Aedes sp. mosquito lives cosmopolitan and breeds in wet environments. Panggungharjo and Bangunharjo villages were categorized as endemic and non-endemic DHF areas, respectively. The aims of this research were to study the characteristics of Aedes sp. mosquito breeding sites, the identity of presence species found in the sites, and the resistance status of Aedes sp. mosquitoes against organophosphate insecticide. The method was using a larval survey which consists of 200 houses as respondents located in Panggungharjo and Bangunharjo villages. The larval resistance was tested by a biochemical method since resistance could be associated with esterase enzyme activity. The characteristics of mosquito breeding sites that found were open containers, filled with clear and calm water, dark and rough wall surfaces, the bottom surface was not directly in contact with the ground, the water temperature was 27-29 °C, pH 6.5-7, and not directly exposed to sunlight. There was only one species of mosquito was found, Aedes aegypti. The resistance test of Aedes sp. larvae showed that Aedes sp. larvae population from Panggungharjo village were susceptible, and Aedes sp. larvae from Bangunharjo village were in moderate resistant against organophosphate insecticide.

Recent Advance in Anaerobic Co-digestion Technology: A Review

Due to their polluting characteristics, fossil fuels presently tend to be replaced by renewable energy resources. Anaerobic digestion is a recent technology for producing biofuels. As a biochemical method to produce biogas, it is more environmentally friendly than other processes and is almost non-polluting. The anaerobic co-digestion is an upgrade of the mono-digestion since some limitations of the single-substrate degradation were solved by digesting two or more substrates. The present review gives an overview of the progress made in the anaerobic co-digestion technology. Appearing as a complex technology, lots of factors can affect its operation. Those factors include the choice and the composition of the substrates, the ratio between the substrates and the inoculum, the pretreatment, the environmental conditions, the operational parameters, and the post-treatment at the end of the process. Analytical and empirical tools for the assessment of the whole system in terms of biodegradability and synergy of the substrates, the efficiency of the process, and the identification of the operation inhibitors are also presented in this paper.

Prooxidant effect of α-tocopherol in pancreatic tumors.

e16698 Background: The coexistence of neuroendocrine tumors and pancreatic adenocarcinoma is rare, and treatment of such mixed tumors is challenging due to the differences in their natural course and response to systemic therapy. There is growing evidence that vitamins affect the biology of pancreatic tumors. The purpose of the study was to measure concentrations of retinol (RET), α-tocopherol (α-TCP) and diene conjugates (DC) in the blood of patients with pancreatic cancer in order to reveal its pathogenetic characteristics. Methods: Blood levels of RET and α-TCP (ELISA methods, Cloud-Clone Corp, USA), their ratio and DC concentrations (biochemical method) were measured before treatment if 42 patients with pancreatic cancer: adenocarcinoma (AC), T1-3N0-1M0, n = 9; AC with a neuroendocrine component (AC+NE) (up to 30%), n = 21; neuroendocrine tumors (NET), T1-3N0-1M0, n = 12. 22 healthy men of similar age were controls. All patients gave their voluntary informed consent for the study. Results: RET levels in all patient were statistically significantly lower than in controls: in AC by 3.8 times, in AC+NE by 1.9 times, in NET by 3.7 times (p = 0.0000). Concentrations of α-TCP in AC were 1.6 times (p = 0.0011) lower than in controls, in AC+NE were similar, and in NET α-TCP was 1.5 times higher than in controls (p = 0.0000). The ratio of α-TCP/RET in all patients significantly exceeded control values: in AC by 2.2 times, in AC+NE by 1.6 times, in NET by 5.7 times (p = 0.0000). Levels of DC in all patients were higher than in controls: in AC by 2.5, in AC+NE by 2.1, in NET by 2.7 times (p = 0.0001). Conclusions: Changes in serum levels of RET and α-TCP differ in patients with AC, NET and mixed tumors, which causes changes in the balance of vitamins and can contribute to a prooxidant effect, as evidenced by an increase in DC levels.