Positive Isolates Research Articles

Protective Effects of Antimicrobial Peptide Microcin J25 (MccJ25) Isolated From Escherichia coli Against Breast Cancer Cells

ABSTRACTMicrocins are antimicrobial peptides (AMPs) with low molecular weight, which are produced by Enterobacterales and have broad‐spectrum antibacterial activity. Alternative approaches like AMPs could help conventional anticancer treatments to fight malignant cells. The present study endeavors to examine the antitumor activity of microcins isolated from different Enterobacterales strains. In total, 120 Enterobacterales isolates were examined after identification. Subsequently, the bacteria were subjected to an agar diffusion test to assess their antibacterial efficacy. Positive isolates were further examined for the presence of Mccj25 using PCR. The cytotoxic effects of isolates harboring the microcin gene were explored using quantitative real‐time PCR (RT‐qPCR) and the MTT test on breast cancer cells. In addition, the expression levels of BCL2 and STAT3 genes were evaluated, and apoptosis was quantified using flow cytometry. The repair rate of normal cells was determined using a scratch assay. The findings obtained from the phenotypic and biochemical assays have duly verified and established the categorization of the Enterobacterales. After conducting the agar diffusion test, a total of 25 isolates of Escherichia coli and Klebsiella pneumoniae displaying inhibition zones were chosen as suitable specimens possessing AMPs. The analysis conducted on the expression of the Mccj25 gene within the aforementioned isolates indicated that Isolate 83 exhibited significant expression of the Mccj25 gene. The extract obtained from this isolate on the breast cancer cell line exhibited the most significant degree of toxicity after 48 h. Furthermore, the treatment of breast cancer cells with Isolate 83 showed that the rate of apoptosis was about 86%, and the expression of BCL2 and STAT3 genes decreased. Contrarily, it potentiated the reparative ability of nontumoral fibroblasts, supporting the in vitro safety toward normal cells and, at the same time, the selectivity against malignant ones. In summary, our results highlighted a significant growth suppression of breast cancer cells with an escalated rate of cellular demise via the apoptosis pathway.

Evaluating the impact of human movement-induced airflow on particle dispersion: A novel real-time validation using IoT technology

Human movement significantly influences local airflow and particle dispersion in indoor environments. Therefore, this study integrates the dynamics of human walking into the analysis of airborne infection risks in a positive pressure isolation ward designed for the protection of immunocompromised patients. Real-time data collection was performed using an anemometer and IoT-based PM sensors to measure airflow velocities and particulate matter (PM) concentrations within a full-scale experimental chamber. Computational Fluid Dynamics (CFD) was used for the numerical simulations, and a User-Defined Function (UDF) code simulated the translational movement of a manikin. The results demonstrated strong agreement with the experimental data, thereby validating the airflow turbulence and Lagrangian-based Discrete Phase Model (DPM) in predicting the airflow velocities and particle transport. The study revealed that human walking substantially enhanced particle dispersion distance by 10-fold compared to static conditions, primarily attributed to intensified air mixing induced by the body movement. Furthermore, the CFD analysis underscored that the direction of walking plays a crucial role in airborne transmission. Specifically, walking away from a patient did not elevate infection risk, whereas approaching a patient significantly increased particle deposition in the patient-occupied region. This study highlights the critical need to consider both movement patterns and directional flow in managing airborne infection risks, contributing to the development of more effective infection control strategies in healthcare settings.

Characterization of blaOXA-232 carrying carbapenem-resistant Klebsiella pneumoniae (CRKP) & their expression profiles under selective carbapenem pressure: An in-depth study from India.

Background & objectives OXA-232 is a five amino acid substitution variant of OXA-48 and is reported in carbapenem-resistant Klebsiella pneumoniae (CRKP), which is associated with nosocomial infections among immunocompromised patients in the intensive care unit. This study aimed to characterise blaOXA-232 in CRKP of clinical origin and investigate its transcriptional response against sub-inhibitory levels of carbapenems. Methods CRKP was isolated from blood (pathogens) and stool cultures (colonisers) of neonates and was characterized for blaOXA-232. Co-existing resistance determinants were investigated in blaOXA-232 positive isolates, followed by horizontal gene transferability assay and PCR-based replicon typing (PBRT). Cloning of blaOXA-232 was performed, and expression of blaOXA-232 in the isolates and their clones under sub-inhibitory concentrations of carbapenems was checked via RT-PCR. Mobile genetic elements associated with blaOXA-232 were investigated, followed by DNA fingerprinting through enterobacterial repetitive intergenic consensus (ERIC) PCR. Results blaOXA-232 with co-carriage of extended-spectrum beta-lactamases (ESBLs), sulphonamides and quinolones were identified in seven CRPK isolates recovered from blood samples of neonates. Transformation and cloning of blaOXA-232 was successful. The sub-inhibitory concentration of carbapenems induces elevated expression of this resistant determinant. ISEcp1 was associated with blaOXA-232 in the upstream region within two haplotypes of CRKP isolates of clinical origin. Interpretation & conclusions Selective carbapenem pressure resulted in higher expression of this gene, which could account for treatment failure. With frequent reports of occurrence among clinical isolates, monitoring and further investigation of this novel variant are necessary to understand its transmission dynamics and to thwart its further dissemination.

Monitoring the VDPV2 outbreak in Egypt during 2020–2021 highlights the crucial role of environmental surveillance and boosting immunization in combating Poliovirus

BackgroundPoliovirus is a highly infectious enterovirus (EV) that primarily affects children and can lead to lifelong paralysis or even death. Vaccine-derived polioviruses (VDPVs) are a great threat since they are derived from the attenuated virus in the Oral Poliovirus Vaccine (OPV) and can mutate to a more virulent form. The purpose of this study was to identify VDPV serotype 2 through the year 2020–2021 via surveillance of sewage samples collected from different localities and governorates in Egypt and stool specimens from Acute Flaccid Paralysis (AFP) cases. Both were collected through the national poliovirus surveillance system and according to the guidelines recommended by the WHO.MethodsA total of 1266 sewage samples and 3241 stool samples from January 2020 to December 2021 were investigated in the lab according to World Health Organization (WHO) protocol for the presence of Polioviruses by cell culture, molecular identification of positive isolates on L20B cell line was carried out using real-time polymerase chain reactions (RT-PCR). Any positive isolates for Poliovirus type 2 and isolates suspected of Vaccine Derived Poliovirus Type 1 and type 3 screened by (VDPV1) or Vaccine Poliovirus Type 3 (VDPV3) assay in RT-PCR were referred for VP1 genetic sequencing.ResultsThe outbreak was caused by circulating VDPV2 (cVDPV2) strains started in January 2021. By the end of February 2021, a total of 11 cVDPV2s were detected in sewage samples from six governorates confirming the outbreak situation. One additional cVDPV2 was detected later in the sewage sample from Qena (June 2021). The first and only re-emergence of VDPV2 in stool samples during the outbreak was in contact with Luxor in June 2021. By November 2021, a total of 80 VDPVs were detected. The Egyptian Ministry of Health and Population (MOHP), in collaboration with the WHO, responded quickly by launching two massive vaccination campaigns targeting children under the age of five. Additionally, surveillance systems were strengthened to detect new cases and prevent further spread of the virus.ConclusionThe continued threat of poliovirus and VDPVs requires ongoing efforts to prevent their emergence and spread. Strategies such as improving immunization coverage, using genetically stable vaccines, and establishing surveillance systems are critical to achieving global eradication of poliovirus and efficient monitoring of VDPVs outbreaks.

Pneumococcal carriage and changes in serotype distribution post- PCV13 introduction in children in Matiari, Pakistan

BackgroundIn early 2021, the 10-valent Pneumococcal conjugate vaccine (PCV10) was replaced with 13-valent (PCV13) by the federal directorate of immunization (FDI), Pakistan. We assessed the impact of a higher valent vaccine, PCV13, on the serotype distribution of nasopharyngeal carriage in rural Pakistan. MethodsChildren <2 years were randomly selected from two rural union councils of Matiari, Sindh in Pakistan between September–October,2022. Clinical, sociodemographic and vaccination histories were recorded. Nasopharyngeal swabs were collected and processed at Infectious Disease Research Laboratory, Aga Khan University, Karachi. Whole genome sequencing was performed on the culture positive isolates. ResultsOf the 200 children enrolled, pneumococcus was detected in 140(70 %) isolates. Majority of age-eligible children (60.1 %,110/183) received 3 PCV13 doses. PCV10 carriage declined from 13.2 %(78/590) in 2017/18 to 7.2 % (10/140) in 2022, additional PCV13 serotypes (3, 6A/6C and 19A) decreased from 18.5 %(109/590) to 11.4 %(16/140) while non-PCV13 serotypes increased from 68.3 %(403/590) to 81.4 %(114/140). There were 88.5 %(n = 124), 80.7 %(n = 113), 55.0 %(n = 77), and 46.0 %(n = 65) isolates predicted to be resistant to cotrimoxazole, penicillin(meningitis cut-off), tetracycline, and erythromycin respectively. ConclusionReplacing PCV10 with PCV13 rapidly decreased prevalence of PCV13 carriage among vaccinated children in Matiari, Pakistan. Vaccine-driven selection pressure may have been responsible for the increase of non-PCV13 serotypes.

Evaluation of antibacterial susceptibility profile in pregnant women with asymptomatic bacteriuria in Kadapa

: The bacterial urinary tract infection in pregnancy may be symptomatic (cystitis, pyelonephritis) or asymptomatic (bacteriuria without symptoms). Empirical antimicrobial therapy may be affected by resistance of uropathogens due to the irrational use of antibiotics. This prevalence of resistance is rising and varies across the globe due to different treatment recommendations which may be determined by taking into account frequently occurring infections, susceptibility patterns, evidence, physician acceptance, antimicrobial stewardship norms, availability of formularies, and antimicrobial prices. So the current research was carried out. : A cross-sectional study was conducted among pregnant women with UTI attending antenatal care (ANC) by excluding pregnant women who had taken antibiotics within the two weeks prior to their ANC follow-up and symptomatic UTI pregnant women. The antibiotic sensitivity of the uropathogens and their identification were evaluated by conventional culture, microbiological techniques and sensitivity tests. The results were analysed by SPSS software for descriptive statistics. : 377 pregnant women with UTI participated in the present study. The results demonstrated that most of the participants who lived in urban areas (64%) were affected. The results also suggest that 42% of participants who had secondary education as the highest level of education, 45% of participants belonged to an upper middle-class family and, 40% of working professionals in the study were affected. Out of 103 isolates, 79 isolates were gram negative &amp; 24 were Gram positive. Out of seventy-nine gram negative isolates, the major contribution was by (36), . (26). Among 24 gram positive isolates, the major contribution was by Coagulase Negative Staphylococci (CONS) (12). The uropathogens were shown diverse antibiotic sensitivity for the study test drugs. : This study concludes that the antibacterial susceptibility and resistance of uropathogens may vary in different geographical areas based on antibiotic usage and circumstances. This study also demonstrated the imperative prerequisite of periodic assessments.

Urinary Tract Infection Due to Streptococcus agalactiae - A Missed Clinical Entity: A Study from a Tertiary Care Center in Southern India

: Streptococcus agalactiae (group B Streptococcus or GBS) commonly causes various urinary tract infections (UTIs), including asymptomatic bacteriuria, cystitis, pyelonephritis, urethritis, and urosepsis. While GBS neonatal disease has decreased, its prevalence in non-pregnant adults has risen. However, its role in UTIs among males and non-pregnant women is less documented. This study aims to investigate the prevalence, clinical presentation, antibiotic susceptibility, and risk factors of GBS UTIs. Over 16 months, a prospective study included all patients diagnosed with GBS UTIs. Among 6305 urine specimens tested, 2.1% (N = 134, 95% CI: 0.68% - 4.8%) were positive for GBS, with a notably higher prevalence among pregnant women (73%, N = 79). This prevalence rate significantly exceeded regional reports, as indicated by a z-score exceeding the critical value. Additionally, 50% of positive isolates were from antenatal patients, indicating pregnancy as a significant risk factor (P &lt; 0.0001). All 134 GBS isolates exhibited sensitivity to penicillin, cefotaxime, ofloxacin, and vancomycin. Sensitivity to cotrimoxazole, erythromycin, and clindamycin was 80%, 95%, and 97%, respectively. Treatment varied by case severity. Uncomplicated cases (41.7% antenatal; 33.5% non-pregnant women and adults) received 3rd or 4th generation cephalosporins, while complicated cases (24.6%, N = 33) required intravenous vancomycin due to comorbidities like chronic kidney disease (CKD), renal calculi, diabetes, and obstetric complications. In conclusion, GBS UTIs predominantly affect females, particularly pregnant women, followed by those with chronic conditions like CKD and diabetes mellitus. Routine GBS culture and susceptibility testing are crucial in laboratories to ensure effective UTI management.

Agroclimatic zone-wise prevalence of biofilm forming methicillin resistant staphylococcus aureus in West Bengal

The present study envisages the prevalence of biofilm producing, methicillin resistant Staphylococcus aureus, isolated from cattle milk of different agro-climatic zones of an eastern state of India, West Bengal. The milk samples (n=168) were collected from three predominant agro- climatic zones of South Bengal, viz. new alluvial, coastal saline and red laterite. A total of 146 Staphylococcus aureus isolates were recovered, confirmed by biochemical tests and polymerase chain reaction (PCR). Through PCR of mecA gene, it was found that 45 strains were methicillin resistant, encompassing 28.57% new alluvial zone, 30.19% red laterite region and 29.16% coastal saline region. Determination of biofilm formation was done, both phenotypically by microtiter plate method and genotypically by PCR of icaA and icaD genes, specific for biofilm formation in Staphylococcus aureus. Phenotypic study revealed that 14 isolates were strong biofilm producers, 79 were moderate and the 47 were weak biofilm producers. PCR studies also showed that a total of 30 isolates were icaA positive and 25 isolates were icaD positive. Although no significant difference was found in the occurrence of icaA positive isolates, the possession of icaD by the Staphylococcus aureus isolates varied significantly according to different agro-climatic zones.

Effect of dry period immunization of Salmonella Dublin latent carriers with a commercial live culture vaccine on intrauterine transmission based on the presence of precolostral antibodies in offspring

Salmonella Dublin latent carrier cows represent a high risk for infection of newborn calves via intrauterine transmission and shedding of bacteria in feces and colostrum at calving. Vaccination of these latent carrier dams during late gestation boosts immunity against S. Dublin. This could reduce the activation of the dormant bacteria during the periparturient immune dysfunction period, thereby reducing the risk of early-life infection in the offspring. Thus, the objective of this study was to evaluate the extent to which vaccinating S. Dublin latent carrier cows at dry-off with a commercial live culture vaccine reduces bacterial shedding at calving and intrauterine infection to calves. To identify latent carriers, we screened 1,084 cows in 4 Michigan commercial dairy farms with a history of S. Dublin. Cows were defined as latent carriers when they showed 3 consecutive positive milk antibody ELISA tests conducted every 2 mo. Subsequently, 148 latent carriers were randomly allocated to the vaccine or control group. Vaccine cows received a commercial live culture vaccine subcutaneously (SC) at dry-off and a booster 2 weeks later. Control cows received saline SC at the same times. At calving, we collected fecal and colostrum samples from the dam and a pre-colostral serum sample from the calf. Bacterial shedding was evaluated in feces and colostrum both qualitatively and quantitatively through bacterial culture and qPCR, respectively. Intrauterine transmission was defined when a calf was positive for serum antibody ELISA at birth. Vaccination decreased the likelihood of calves being born S. Dublin seropositive (Relative Risk [95%CI]) = 0.19 [0.04 - 0.84]). However, no S. Dublin positive isolates were identified through either bacteriological culture or qPCR in feces or colostrum. Vaccination of S. Dublin latent-carrier cows at dry-off reduced intrauterine transmission to calves. Further research is warranted into the potential of vaccination to decrease vertical transmission of S. Dublin in dairy farms. Additionally, the absence of S. Dublin positive fecal and colostrum samples warrants further evaluation of the detection methods for identifying latent carriers or S. Dublin isolation, as well as the role of latent carriers in infecting newborn calves in the maternity area at birth.

Assessment of in vitro activity of ceftazidime/avibactam on carbapenemase-producing Enterobacterales from Iran: An experimental study.

The prevalence of carbapenemase-producing Enterobacterales (CPE) continues to increase worldwide. Combination of β-lactam and novel β-lactamase inhibitors introduce a revolutionary treatment option for CPE. Ceftazidime/avibactam (CAZ/AVB) has been recently developed for treatment of severe infections caused by multidrug-resistant bacteria. We aimed to evaluate in vitro activity of CAZ/AVB on a collection of 85 ESBL-producing-carbapenemase negative and CPE from Iran. ESBL and carbapenemase production was phenotypically confirmed by combined disk test and modified carbapenem inactivation method respectively. The presence of clinically important carbapenemase encoding genes was examined using PCR. Susceptibility of all isolates to CAZ/AVB was determined using discs containing 30 μg ceftazidime +20 μg avibactam (AVB). Minimum inhibitory concentrations (MICs) of CAZ/AVB in 28 CPE (4 Escherichia coli and 24 Klebsiella pneumoniae) was determined by gradient diffusion method using MIC test strips (0.016-256 mg/L ceftazidime +4 mg/L AVB). All phenotypically identified ESBL positive-carbapenemase negative isolates were found to be susceptible to CAZ/AVB. Among the carbapenem resistant isolates, CAZ/AVB showed potent inhibitory activity against all OXA-48-like (MIC ranges 0.125/4-0.75/4 mg/L) and KPC positive isolates (MIC ranges <0.016/4-0.19/4 mg/L). However, AVB could not restore the activity of ceftazdime against isolates producing metallo-β-lactamases (MLBs) including VIM, NDM (MIC > 256/4 mg/L) and IMP (MIC > 8/4 mg/L). Our data highlighted the excellent in vitro performance of CAZ/AVB against ESBL-producing and CPE suggesting that this combination can efficiently be used as therapeutic option for management of CPE infections particularly in regions with high prevalence of KPC and/or OXA-48-like positive but MBL-negative Enterobacterales.

Functional Attributes of Gut Guardians: Probiotic Potential of Lactobacillus strains isolated from Traditional Nepalese Fermented Foods

The interplay between the gut microbiome and fermented foods has significant implications for human health and nutrition. Fermented foods, rich in beneficial microorganisms such as Lactic Acid Bacteria (LAB) including Lactobacillus spp., have attracted considerable research interest due to their potential probiotic effects. The six Nepalese fermented foods selected for this research—homemade yogurt, commercial yogurt, gundruk, tama, chhurpi, and achaar—are recognized for their diverse microbial profiles and purported health benefits, commonly consumed across various regions of Nepal. This study aims to elucidate their probiotic potential through tests such as acid and salt tolerance and their antimicrobial effects against five pathogens (Staphylococcus aureus, Klebsiella pneumoniae, Escherichia coli, Pseudomonas aeruginosa, and Salmonella spp.). A total of 120 samples of these six different fermented foods were collected from households and local markets in Chitwan District. Among 120 fermented food samples, 103 samples (85.83%) were found to be LAB positive. Out of the total sample, 64 samples (53.30%) were found to be Lactobacillus spp. positive. These positive isolates were further tested for their pH tolerance, NaCl tolerance, and antibacterial potential. Upon research, 18 isolates were found to be tolerant at pH 2, and 21 isolates were found to be tolerant at 8% NaCl concentration. The highest antibacterial effect of Lactobacillus spp. was found against Staphylococcus aureus with ZOI 18 mm and lowest against Escherichia coli. The study here contributes to the importance of utilizing the microbial diversity present in fermented foods, along with providing valuable insights for developing novel probiotic interventions for enhancing gut and overall health. Moreover, the research highlights the potential of traditional fermented foods as a valuable source of probiotic strains, paving the way for innovative approaches to improve health through diet.

Comprehensive Assessment of Initial Adaptation of ESBL Positive ST131 Escherichia coli to Carbapenem Exposure.

It remains unclear how high-risk Escherichia coli lineages, like sequence type (ST) 131, initially adapt to carbapenem exposure in their progression to becoming carbapenem resistant. Carbapenem mutation frequency was measured in multiple subclades of extended-spectrum β-lactamase (ESBL) positive ST131 clinical isolates using a fluctuation assay followed by whole genome sequencing (WGS) characterization. Genomic, transcriptomic, and porin analyses of ST131 C2/ H 30Rx isolate, MB1860, under prolonged, increasing carbapenem exposure was performed using two distinct experimental evolutionary platforms to measure fast vs. slow adaptation. All thirteen ESBL positive ST131 strains selected from a diverse (n=184) ST131 bacteremia cohort had detectable ertapenem (ETP) mutational frequencies with a statistically positive correlation between initial ESBL gene copy number and mutation frequency (r = 0.87, P -value <1e-5). WGS analysis of mutants showed initial response to ETP exposure resulted in significant increases in ESBL gene copy numbers or mutations in outer membrane porin (Omp) encoding genes in the absence of ESBL gene amplification with subclade specific associations. In both experimental evolutionary platforms, MB1860 responded to initial ETP exposure by increasing bla CTX-M-15 copy numbers via modular, insertion sequence 26 (IS 26 ) mediated pseudocompound transposons (PCTns). Transposase activity driven by PCTn upregulation was a conserved expression signal in both experimental evolutionary platforms. Stable mutations in Omp encoding genes were detected only after prolonged increasing carbapenem exposure consistent with clinical observations. ESBL gene amplification is a conserved response to initial carbapenem exposure, especially within the high-risk ST131 C2/ H 30Rx subclade. Targeting such amplification could assist with mitigating carbapenem resistance development.

Extended-spectrum beta-lactamase and carbapenemase producing Klebsiella Pneumoniae isolated from patient with suspected urinary tract infection

Urinary tract infection (UTI) is the most common bacterial infections in humans and serious health problem in many parts of the world. Carbapenem resistant Enterobacteriaceae (CRE) are increasingly reported from healthcare facilities in Nepal and around the world. This study is carried out with an objective to assess the Prevalence of ESBL and carbapenemase producing Klebsiella pneumoniae isolate from patient with suspected of UTI. Total 880 urine sample was collected during 6-month period and processed and identified by using conventional microbiological procedure and biochemical test. ESBL screening isolates were done by using Ceftazidime and Ceftazidime with clavulanic acid. Production of ESBL was determine by combination Disc Test. For the confirmation of carbapenemase producing K. pneumoniae Modified Hodge Method, Carbapenem Inactivation Method and EDTA Impregnated Disc test (MBL) was performed. Out of total sample, 9.30% (82) showed significant growth. Prevalence of UTI seen more in male as compare to female patients. Out of positive isolates, 37.8% were K. pneumoniae. K. pneumoniae were resistance with Ceftriaxone (54.8%) followed by 51.61% Ceftazidime, Cotrimoxazole. Multi drug resistance (MDR) was found to be 54.83%. Out of 31 isolates, 10(32%) were confirmed as ESBL positive by Combination Disc Assay. 14 isolates were screened as carbapenemase producers but 2(14.28%) showed positive through Modified Hodge Method, 4(28.57%) Modified Carbapenem Inactivation Method and 7(50%) EDTA impregnated Disc Test (MBL). Analytically, the sensitivity of MHT, CIM, and MBL tests was 42.81%, 58.10%, and 76.96%, respectively, all with 100% specificity. Colistin was the drug of choice, with 93.54% of isolates showing sensitivity to it. Early detection of ESBL and MBL-producing isolates is crucial for reducing mortality rates and preventing the intra-hospital spread of these strains.

Quantification using a HPLC-FLD-based Detector and Molecular Identifi-cation of Ochratoxin-A Producing Aspergillus Species Isolated from Stored Grain Samples.

Quantification using an HPLC-FLD based detector and Molecular identification of Ochratoxin-A producing Aspergillus Species isolated from stored grain samples. Fungi are cosmopolitan in origin and are known to grow in any suitable substra-tum. In the present investigation, Aspergillus species isolated from stored grain samples were analyzed for ochratoxin-A production. The objective of this study is the quantification of Ochratoxin and identification of ochratoxigenic fungi. A total of n=34 black Aspergilli and n=1 Ochre Aspergilli were isolated from grain samples of Bihar, India and it was tested for OTA production. The limit of detection (LOD) is found to be 0.33μg/Kg and the limit of quantification (LOQ) is found to be 1μg/Kg for OTA in HPLC-FLD. In the present study, out of all the fungal isolates, only TiB fungal isolate was able to produce the ochratoxin-A above the level of LOQ. The positive isolate TiB obtained from stored sesame seed samples was able to produce 25.54 μg/Kg of OTA. ITS sequence analysis of TiB isolate was able to matche 100% with Aspergillus welwitschiae and Aspergillus foetidus. This is the initial report of ochratoxigenic Aspergillus fungal isolate isolated from stored sesame seed samples of flood-prone areas of Bihar, India.

Use of magnetic fluids in process system for pipe isolations

This paper investigates the use of magnetic fluids known as ferrofluids to act as ad hoc valves within pipe systems to create isolation points for stemming pipe leakages and to halt leakages before they become largescale disasters. The sealing abilities of ferrofluids were proven for microvalves (ID ≤ 1 mm) in hydrostatic experiments and extended to the macroscale applications (ID ≥ 6 mm). Theoretical prediction and magnetic finite element analysis (FEA) were also undertaken to predict the burst pressure, and a comparison of both results against the experimental measurement was made. The up-scale results (10–18 mm ID) indicated that it is feasible to develop a ferrofluid that can be extended to approximate the applicable magnet strength to achieve higher burst pressure. It was concluded that the ferrofluid isolation valves hold potential in macroscale environments for process engineering in favour of a positive isolation.

Bacteriological profile of bloodstream infections in pediatric age group in a tertiary care centre, Solapur

Bloodstream infections (BSI) due to multidrug-resistant organisms from paediatric setup have become increasingly common. BSI can be transient and be rapidly cleared out by the host defence mechanism or be associated with high morbidity and mortality if it becomes persistent.Blood samples were collected from 1112 children within a 1-year study period (July 2022 to June 2023) which included all children admitted with complaint of fever and suspected of having sepsis in Paediatric department of Shri Chhatrapati Shivaji Maharaj Sarvopchar Rugnalaya (SCSMSR), Solapur. Blood volume was collected depending upon age and body weight of the patient with aseptic precautions and inoculated in Brain Heart Infusion broth (BHI) which was incubated at 37°C for 7 days. Subcultures were made on blood agar and MacConkey agar plates. Organisms were identified by biochemical reactions and antibiotic susceptibility test of the isolates were performed by disk diffusion. Out of 1112 suspected cases, 175 (15.74%) were culture positive. (27.43%) was the most common isolate followed by (16.57%) Most common Gram positive isolate was (11.43%) followed by (6.86%). Total Multidrug resistant (MDR) isolates in Gram negative and Gram positive were 50.35% and 31.25% respectively.High rates of antibiotic resistance are observed in both gram positive and gram negative organisms. Thus, there is an urgent need for proper implementation of antibiotic stewardship programme and infection prevention and control measures.

The Genomic Epidemiology of Clinical Burkholderia pseudomallei Isolates in North Queensland, Australia.

Background:Burkholderia pseudomallei, the causative agent of melioidosis, is highly genetically recombinant, resulting in significant genomic diversity. Multiple virulence factors have been associated with specific disease presentations. To date, there are limited data relating to genomic diversity and virulence factors associated with melioidosis cases in North Queensland, Australia. Aim: To describe the genetic diversity of B. pseudomallei and identify virulence factors associated with clinical risk factors and patient outcomes. Methods: Whole genome sequencing of clinical isolates was performed and analysed with clinical data obtained from a retrospective melioidosis cohort study. Results: Fifty-nine distinct sequence types (STs) were identified from the 128 clinical isolates. Six STs comprised 64/128 (50%) isolates. Novel STs accounted for 38/59 (64%) STs, with ST TSV-13 as the most prevalent (n = 7), and were less likely to possess an LPS A genotype or YLF gene cluster (p < 0.001). These isolates were most likely to be found outside the inner city (aOR: 4.0, 95% CI: 1.7-9.0, p = 0.001). ST TSV-13 was associated with increased mortality (aOR: 6.1, 95% CI: 1.2-30.9, p = 0.03). Patients with a history of alcohol excess were less likely to be infected by fhaB3 (aOR 0.2, 95% CI: 0.1-0.7, p = 0.01) or YLF (aOR: 0.4, 95% CI: 0.2-0.9, p = 0.04) positive isolates. Conclusions: There are a significant number of novel sequence types in Townsville, Australia. An emerging novel ST appears to have an association with geographic location and mortality. Ongoing investigation is required to further understand the impact of this ST on the Townsville region.

ANTIMICROBIAL RESISTANCE PATTERNS AMONG BACTERIAL PATHOGENS ISOLATED FROM CLINICAL SAMPLES IN SANA'A HOSPITALS

Background and objectives: Yemen is among the developing nations where antimicrobial resistance (AMR) is posing a danger to public health. AMR can lead to increased morbidity and mortality from treatment failures and a lack of effective therapies. Particularly in the research arena, there is a dearth of knowledge about the antimicrobial resistance patterns of frequently isolated, locally occurring diseases. Therefore, the purpose of this study was to evaluate the diseases' microbiological profiles and resistance trends in Sana'a, Yemen. Methods: In Sana'a, Yemen, a retrospective study was carried out at various governmental and private hospitals between June and September of 2020. Information about antibiotic susceptibilities and cultures was taken from the microbiology department's 2019 files. The data analysis method employed was descriptive statistics. Results: This study includes 4156 pathogen isolates, with 58.2% of the isolates being Gram negative. Of all the isolates, urine (26.1 %, n = 1086) and pus specimens (24.6 %, n = 1025) demonstrated the greatest detection rates. The most often isolated pathogens were S. aureus (35.6%, n=1479), E. coli (29.2%, n=1215), P. aeroginosa (14.1%, n=586), and Klebsiella species (10.7%, n=443). The highest rates of resistance were found for cephalosporins (cefixime 90%, cefadroxil 87.9%, cefepime 72%, and ceftriaxone 70%) and penicillins (carbincillin 87%, amoxacillin 80%, and amoxacillin/clavulanic acid 77%). Gram positive and Gram negative isolates showed minimal resistance to linezolid and vancomycin, with Enterococcus showing higher resistance. Colistin was most effective against Gram negative, while E. coli, Klebseilla, and Proteus showed high resistance. Conclusions: The high rate of resistance discovered in the current study in both Gram-positive and Gram-negative organisms is alarming and highlights the necessity of routinely determining the prevalence of resistance in a given area in order to guide empirical therapy and choose the most effective course of antibiotic treatment. Peer Review History: Received 27 March 2024; Revised 8 May 2024; Accepted 27 June; Available online 15 July 2024 Academic Editor: Prof. Dr. Gorkem Dulger, Duzce University, Turkey, gorkemdulger@yandex.com Average Peer review marks at initial stage: 6.5/10 Average Peer review marks at publication stage: 7.0/10 Reviewers: Dr. Heba M. Abd El-Azim, Damanhour University, Egypt, h_m_abdelazim@hotmail.com Dr. Jennifer Audu-Peter, University of Jos, Nigeria, drambia44@gmail.com

Cryptosporidium Infections in Neonatal Calves on a Dairy Farm.

This study was conducted with the aim of the molecular identification of the protozoan parasite Cryptosporidium spp. in calves in the early stage of their development on a dairy farm in Eastern Slovakia. Twenty-five Holstein and Holstein cross calves were included in the study and monitored from their birth to the fifth week of life (1-5 weeks). Fresh fecal samples were collected from the same group of calves each week, except during the fourth week, and with the exception of Sample 8. All samples were analyzed using the Ziehl-Neelsen staining method and coproantigen was tested using the ELISA test as the screening method. Using the ELISA method, the highest incidence of cryptosporidiosis was observed in the second week of life of the calves, while the antigen was detected in 21 (91.6%) calves. Using the Ziehl-Neelsen staining method, the highest incidence was also observed in the second week, with an incidence rate of 62.5%. Positive isolates confirmed by the ELISA test were molecularly characterized. The species and subtypes of Cryptosporidium in the positive isolates were identified using PCR and the sequence analysis of the small subunit of the ribosomal 18S RNA (ssu rRNA) and the 60 kDa glycoprotein (gp60) genes of the parasite. The sequence analysis of 29 isolates at the 18S rRNA loci confirmed the presence of two species-Cryptosporidium parvum and Cryptosporidium ryanae. Out of 29 isolates, 25 were assigned to the species C. parvum, with the gp60 locus identified as genotype IIaA17G1R1. Among the individual animal groups, calves are the most common reservoirs of the C. parvum zoonotic species. This disease has significant public health implications as contact with livestock and their feces and working with barn manure are major sources of infection, not only for other animals but also for humans.

Incidence and clinical significance of non-tuberculous mycobacteria among migrants in Denmark: A nationwide register-based cohort study from 1991 through 2021

BackgroundThere is limited knowledge about non-tuberculous mycobacteria (NTM) infections in migrants. We aimed to assess the incidence and clinical significance of NTM among migrants in Denmark. MethodNationwide register-based cohort study of migrants with a positive NTM culture in Denmark from 1991 through 2021, stratified by patient demographics, disease localisation, species, and clinical significance. Results433 migrants had a positive NTM culture, resulting in an overall incidence rate (IR) of 3.7 (95%CI 3.3–4.0) per 100,000 migrants. Overall NTM IRs for definite disease were 1.0 (95%CI 0.9–1.2), possible disease 1.0 (95%CI 0.8–1.2), and isolation 1.7 (95%CI 1.4–1.9) per 100,000 migrants. Migrants had considerably higher age- and sex-adjusted NTM IRs of positive cultures (incidence rate ratio [IRR] = 2.1, 95%CI 1.9–2.3, p < 0.001), possible disease (IRR = 2.4, 95%CI 2.0–3.0, p < 0.001), and isolation (IRR = 4.6, 95%CI 3.9–5.4, p < 0.001) compared to Danish-born, but not of definite disease (IRR = 1.1, 95%CI 0.9–1.3, p = 0.562). IRs of migrants with positive NTM cultures did not increase over time (−0.8 %/year, p = 0.133). ConclusionsMigrants have a higher, but stable, burden of NTM compared with Danish-born. The higher rates likely reflect that more specimens are examined for Mycobacterium tuberculosis. Microbiologically classified definite NTM disease is not substantially more common among migrants.