Clinical Specimens Of Patients Research Articles

GFPT2 expression is induced by gemcitabine administration and enhances invasion by activating the hexosamine biosynthetic pathway in pancreatic cancer

Our previous studies revealed a novel link between gemcitabine (GEM) chemotherapy and elevated glutamine-fructose-6-phosphate transaminase 2 (GFPT2) expression in pancreatic cancer (PaCa) cells. GFPT2 is a rate-limiting enzyme in the hexosamine biosynthesis pathway (HBP). HBP can enhance metastatic potential by regulating epithelial-mesenchymal transition (EMT). The aim of this study was to further evaluate the effect of chemotherapy-induced GFPT2 expression on metastatic potential. GFPT2 expression was evaluated in a mouse xenograft model following GEM exposure and in clinical specimens of patients after chemotherapy using immunohistochemical analysis. The roles of GFPT2 in HBP activation, downstream pathways, and cellular functions in PaCa cells with regulated GFPT2 expression were investigated. GEM exposure increased GFPT2 expression in tumors resected from a mouse xenograft model and in patients treated with neoadjuvant chemotherapy (NAC). GFPT2 expression was correlated with post-operative liver metastasis after NAC. Its expression activated the HBP, promoting migration and invasion. Treatment with HBP inhibitors reversed these effects. Additionally, GFPT2 upregulated ZEB1 and vimentin expression and downregulated E-cadherin expression. GEM induction upregulated GFPT2 expression. Elevated GFPT2 levels promoted invasion by activating the HBP, suggesting the potential role of this mechanism in promoting chemotherapy-induced metastasis.

Retrospective Characterization of Bone Histomorphometric Findings in Clinical Patient Specimens.

Bone histomorphometry provides comprehensive information on bone metabolism and microstructure. In this retrospective study, we aimed to obtain an overview of the typical indications, referring hospitals, and histomorphometric quantification-based diagnoses of the bone tissue in our histomorphometry laboratory, the only laboratory in Finland carrying out histomorphometric examination of clinical bone biopsies. Between January 1, 2005 and December 31, 2020, 553 clinical bone biopsies were sent to our histomorphometry laboratory for histomorphometric examination. The median age of the patients was 55 years (range, 0.2-89.9 years), 51% of them were males, and 18% comprised pediatric patients. We received bone biopsy specimens from 23 hospitals or healthcare units. The majority of the samples we sent by nephrologists. The most common bone biopsy indications were suspicion of renal osteodystrophy (ROD), unknown bone turnover status in osteoporosis, and several or untypical fractures. The most common quantitative bone histomorphometry-based diagnosis was ROD. This study provides information on the clinical application of bone histomorphometry in Finland. Precise and quantitative ROD evaluation is the most common indication for bone histomorphometry, being crucial in clinical decision-making and targeted treatment of this patient group.

Molecular detection of blaNDM and blaOXA-48 genes in Carbapenem-Resistant Klebsiella pneumoniae isolates from a tertiary care hospital

BackgroundThe incidence of carbapenem-resistant Klebsiella pneumoniae (CRKP) infections is increasing globally. In India, around 65% of K. pneumoniae isolates are resistant to carbapenem antibiotics. The blaNDM is the predominant carbapenem-resistant gene in CRKP isolates. However, blaOXA-48 has also been reported to be increasing in recent days. MethodsK. pneumoniae strains isolated from the clinical specimens of patients attending a tertiary care hospital in Hyderabad from June 2021 to May 2022 were included in this study. Resistance to carbapenems and other antibiotics was screened using Kirby-Bauer’s disc diffusion method. Phenotypic tests such as the Carbapenemase Nordmann Poirel (CarbaNP) test, Modified Carbapenem Inactivation Method (mCIM), and EDTA Carbapenem Inactivation Method (eCIM) were used to detect the carbapenemase producers. The genes responsible for carbapenemase production were detected by the real-time polymerase chain reaction (RT-PCR) method. ResultsOut of 1265 K. pneumoniae strains isolated, 241 (19 %) isolates showed resistance to any one of the carbapenem antibiotics tested. Phenotypic tests such as CarbaNP, mCIM, and eCIM revealed that 94.6 %, 97.1 %, and 95.4 % of CRKP isolates were carbapenemase producers, respectively. About 66.4 % of CRKP isolates harbored blaNDM, 17.4 % harbored blaOXA-48, and 16.2 % harbored both blaNDM and OXA-48 genes. None of the isolates tested positive for blaKPC, blaVIM, and blaIMP genes. ConclusionIn this study, blaNDM is the most prevalent carbapenemase gene in CRKP isolates. Furthermore, blaOXA-48 and the co-existence of both blaNDM and blaOXA-48 genes were also found. CRKP is emerging as a serious threat among drug-resistant bacterial pathogens which would complicate the treatment of bacterial infections with available antibiotics.

Occurrence of Staphylococcus aureus among Inpatients of a Tertiary Hospital in Jalingo, Taraba State, Nigeria

Patients stay longer on admission as a result of being infected by certain pathogens like S.aureus. One hundred isolates were obtained from clinical specimens of patients who had stayed for not less than 72 hours in male and female wards of Specialist hospital, Jalingo. The specimens used were sputum, nasalswab, throat swab and wound swab. Standard procedures were used in the isolation and identification of the bacteria as well as in determining the antimicrobial resistance profile. However, resistance to cefoxitin was used to identify the MRSA Neverthless, 21% of the isolates were S. aureus while 61.9% of the S.aureus were MRSA. Though, the prevalence of S.aureus was highest (23.1%) in the nasal swab of inpatients aged 46-55(p=0.054), wound swab (17.4%) of inpatients aged 26-35(p=0.254), throat swab (6.5%) of inpatients aged 36-45 years (p=0.935) and sputum (3.0%) of inpatients aged 36-45 and 76-85(p=0.009), all the S.aureus isolated from the nares were MRSA. All the S.aureus were multi drug resistant-they were respectively 76.2%,90.5%,81.0%,85.7%,47.6% and 52.3% resistant to gentamycin (10μg), ciprofloxacin (20μg), streptomycin (10μg), erythromycin(10μg), cefuroxime (30μg) and levofloxacin (20μg).However,100% resistance was observed in Ampiclox(30μg), Amoxacillin(30μg). Zinnocef (20μg), Cefriaxone (20μg) and cefoxime (10μg).It is therefore recommended that further study be carried out to find out whether there is a relationship between the prevalence of MRSA and the site of isolation(specimen). Also, there is need to find out if there are conditions in the nares that promote the acquisition of mec A gene by S.aureus.

A Prospective, Observational and Comparative Study of In-Vitro Susceptibility of Isepamicin against Clinical Isolates from Various Clinical Sources (Triple I Study - Isepamicin in India)

Objectives: This study aims to investigate the in-vitro susceptibility of clinical isolates against Isepamicin and compared it with Gentamicin and Amikacin.
 Patients and Methods: In this multicentre prospective study, clinical specimens of patients were collected from three different regions of India. Clinical isolates from urine, intra-abdominal, broncho-alveolar lavage, endotracheal secretion, and sterile blood were included. The E-test was used to quantify the minimal inhibitory concentration (MIC) for Isepamicin, Gentamicin, and Amikacin. The percentages of bacterial isolates were categorized as susceptible, intermediate, and resistant according to the European Committee on Antimicrobial Susceptibility Testing (EUCAST) guidelines as per Comité de l'Antibiogramme de la Société Française de Microbiologie (CA-SFM) recommendation.
 Results: A total of 8 different bacterial isolates were collected from 150 clinical samples obtained from 50 patients. Respiratory (63 [42%]) and urine (44 [29.3%]) specimens were the most common sources for bacterial strains. The most identified bacterial isolates were K. pneumoniae (40 [26.6%]) and P. aeruginosa (38 [25%]). Isepamicin was found to be highly effective in urine samples and showed excellent sensitivity against E. coli (93.3%), followed by P. aeruginosa (57.9%) and K. pneumoniae (55.0%). Antimicrobial sensitivity was highest for Isepamicin (60/108 [56%]) at MIC≤1 mg/L and was most effective against Gram-negative bacterial isolates from the intensive care units (ICUs).
 Conclusions: Isepamicin could treat E. coli infections and could be an effective therapy in the treatment of urinary tract infections (UTIs). Moreover, it could also be used as an alternative to Gentamicin and Amikacin against resistant cases.
 Keywords: Aminoglycosides, Amikacin, E. coli, Gentamicin, Gram-negative bacteria, Isepamicin.

Associations between β-Lactamase Types of Acinetobacter baumannii and Antimicrobial Resistance.

Background and objective: Acinetobacter baumannii (A. baumannii) is an important nosocomial pathogen that not only possesses intrinsic resistance to many classes of antibiotics, but is also capable of rapidly developing antimicrobial resistance during treatment. The aim of this study was to determine the characteristics of resistance of A. baumannii strains to β-lactams and other tested antibiotics, to evaluate the associations between the phenotypes of resistance to β-lactams and other tested antibiotics, and to evaluate the changes in antibiotic resistance of A. baumannii strains over 5 years by comparing the periods of 2016-2017 and 2020-2021. Materials and methods: A total of 233 A. baumannii strains were isolated from different clinical specimens of patients treated at the Hospital of Lithuanian University of Health Sciences in 2016-2017 (n = 130) and 2021-2022 (n = 103). All clinical cultures positive for A. baumannii were analyzed. The type of β-lactamase was detected by phenotypic methods using ESBL plus AmpC screen disk tests and the combination meropenem disk test. Results: In both periods, all A. baumannii strains were resistant to ciprofloxacin; resistance to carbapenems, piperacillin/tazobactam, gentamicin, and tobramycin was noted in more than 80% of strains. A comparison of two periods showed that the percentages of A. baumannii strains producing two or three types of β-lactamases were significantly greater in 2021-2022 than in 2016-2017 (94.2% and 5.8% vs. 17.7% and 2.3%, respectively, p < 0.001). Isolates producing two or three types of β-lactamases were more often resistant to tigecycline, tetracycline, and doxycycline than strains producing one type of β-lactamase (p < 0.001). Conclusions: The frequency of isolation of A. baumannii strains producing two different types of β-lactamases (AmpC plus KPC, AmpC plus ESBL, or ESBL plus KPC) or three types of β-lactamases (AmpC, KPC, and ESBL) and the resistance rates to ampicillin/sulbactam, tigecycline, tetracycline, and doxycycline were significantly greater in 2020-2021 as compared with 2016-2017. The production of two or three types of β-lactamases by A. baumannii strains was associated with higher resistance rates to tetracyclines.

Activation of SARS-CoV-2 by trypsin-like proteases in the clinical specimens of patients with COVID-19

SARS-CoV-2 enters host cells through the angiotensin converting enzyme 2 (ACE2) receptor and/or transmembrane protease, serine 2 (TMPRSS2). In this study, we investigated whether proteases increased SARS-CoV-2 infectivity using pseudotyped viruses and clinical specimens from patients with COVID-19. First, we investigated how trypsin increased infectivity using the pseudotyped virus. Our findings revealed that trypsin increased infectivity after the virus was adsorbed on the cells, but no increase in infectivity was observed when the virus was treated with trypsin. We examined the effect of trypsin on SARS-CoV-2 infection in clinical specimens and found that the infectivity of the SARS-CoV-2 delta variant increased 36,000-fold after trypsin treatment. By contrast, the infectivity of SARS-CoV-2 omicron variant increased to less than 20-fold in the clinical specimens. Finally, using five clinical specimens containing delta variants, enhancement of viral infectivity was evaluated in the presence of the culture supernatant of several anaerobic bacteria. As a result, viral infectivities of all the clinical specimens containing culture supernatants of Fusobacterium necrophorum were significantly increased from several- to tenfold. Because SARS-CoV-2 infectivity increases in the oral cavity, which may contain anaerobic bacteria, keeping the oral cavities clean may help prevent SARS-CoV-2 infection.

Molecular Detection of Extended Spectrum Beta-Lactamase Gene in Clinical Isolates of Klebsiella Species in Jos North Central of Nigeria

Aims: The aim of the study was to determine the antimicrobial susceptibility of Klebsiella species, prevalence of Extended Spectrum Beta-Lactamases (ESBLs) and the gene coding ESBL production in Klebsiella Species obtained from clinical specimens of patients attending Plateau State Specialist and Jos University Teaching Hospitals both in Jos North Central of Nigeria.&#x0D; Study Design: This was hospital based study conducted in the Department of Medical Microbiology unit of Plateau State Specialist and Jos University Teaching Hospital (JUTH) during the periods of January to April 2020.&#x0D; Methodology: Out of 156 non-motile, oxidase negative gram negative organisms collected, 137 isolates were identified to be Klebsiella species using oxoid Microbact 24E kit for Enterobacteriaceae identification and Microsoft for bacteria identification. Antimicrobial Susceptibility Testing (AST) and ESBL screening was done by Kirby-Bauer disk diffusion method using oxoid Single disk antibiotics which include Ceftazidime (30µg), Cefotaxime (30µg), Imipenem (10µg), Ciprofloxacin (5µg), Gentamicin (10µg), Ampicillin (10 µg), Aztreonam (30 µg), and Azithromycin (15 µg) on Mueller Hinton Agar (oxoid).Break point was determined by CLSI AST guidelines. The isolates that showed resistance or reduced susceptibility to Ceftazidime and Cefotaxime are suspected to be ESBL positive Klebsiella. Phenotypic confirmation of ESBL positive isolates was carried out using Double Disk Synergy Test (DDST) with Ceftazidime 30µg (oxoid), Cefotaxime 30µg (oxoid) and Amoxicillin Clavulanic acid 20/10ug (Oxoid).Genotypic detection of ESBL gene was done using Polymerase Chain Reaction (PCR).&#x0D; Results: Antimicrobial Susceptibility Test showed Imipenem to be highly sensitive to ESBL positive Klebsiella pneumonia with 100% sensitivity. Gentamicin, Ampicillin, and Azithromycin showed reduced susceptibility. Genotypic results showed presence of bla TEM, bla SHV genes at 868bp and 972bp band size with no occurrence of bla CTX-M gene. There was multiple occurrence of gene in some of the isolates tested while some recorded no ESBL gene. The ESBL prevalence of 15.3% was recorded in this study.&#x0D; Conclusions: The prevalence of 15.3% recorded in this study is low compared to other studies from some other states within the country. Efforts should be put in place to ensure non-proliferation of this ESBL Klebsiella strain as it creates not only a therapeutic challenge but health problem.

Distribution and antifungal resistance rate of yeast isolated from various samples

Objective: Yeast causes hospital-acquired infections at increasing rates, which can cause serious mortality, especially in patients with a suppressed immune system. This study aimed to determine the species distribution and antifungal resistance rates of yeast isolated in a hospital. Material and Methods: Isolated yeasts from clinical specimens of patients who received inpatient treatment in different clinics in our hospital between 1 December 2019 and 30 September 2020 were examined. In all of these isolates, species identification was made with an automated system in addition to classical methods. Additionally, the antifungal susceptibility of yeast against amphotericin B, flucytosine, Fluconazole, micafungin, caspofungin, and Voriconazole was investigated using an automated system. Results: In the study, yeasts isolated from 183 clinical samples, including 64 vagen, 62 blood, 28 urine, 12 wounds, eight tracheal aspirates, five peritoneal fluids, three catheters and one cerebrospinal fluid (CSF) samples were included. Of these isolates, 93 were Candida albicans (50,82%), 40 were Candida parapsilosis (21,86%), 17 were Candida tropicalis (9,29%), eight were Candida glabrata (4,37%), eight were Stephanoascus ciferrii (4,37%), five were Candida lusitaniae (2,19%), four were Candida famata (2,19%), four were Cryptococcus laurentii (2,19%) and four were Candida krusei ( 2,19%). Antifungal susceptibility testing was performed in 103 of the isolates. The highest resistance was found against Fluconazole, with 16.8%, and the lowest resistance was against flucytosine, with 2.2%. Antifungal resistance rates of Fluconazole, Voriconazole, amphotericin B, flucytosine, caspofungin and micafungin were found as 16.8%, 8.2%, 6.1%, 2.2%, 2.9% and 6.8% respectively. Conclusion: Due to the increasing frequency of fungal infections due to long-term hospitalization, it has been concluded that identifying the causative species and reporting the antifungal susceptibility status is important in monitoring the change in resistance rates and guiding the treatment.

Isolation of the rare opportunistic yeast &lt;i&gt;Saprochaete capitata&lt;/i&gt; from clinical specimens of patients with SARS CoV 2 infection

Not available.

Genetic relatedness of third-generation cephalosporin-resistant Escherichia coli among livestock, farmers, and patients in Japan

ObjectivesThe third-generation cephalosporin (3GC)-resistant E. coli strains have been detected worldwide in humans and animals. Hence, in this study, we evaluated the prevalence and genetic characteristics of 3GC-resistant E. coli in livestock, farmers, and patients to further analyse if livestock serves as a potential reservoir of antimicrobial-resistant bacteria. MethodsFaecal samples were collected from 330 healthy livestock (216 cattle and 114 swine), 61 healthy livestock farmers (52 cattle farmers and 9 swine farmers), and 68 non-duplicate 3GC-resistant E. coli isolates were also obtained from the clinical specimens of patients in Japan between 2013 and 2015. Genes associated with resistance in 3GC-resistant E. coli were identified using polymerase chain reaction (PCR) and DNA sequencing. Genotypic diversity was determined by multilocus sequence typing (MLST) and pulsed-field gel electrophoresis (PFGE). ResultsWe obtained 39 and 17 non-duplicated 3GC-resistant E. coli strains from healthy livestock (33 cattle and six swine) and livestock farmers, respectively. All isolates carried either CTX-M-type extended-spectrum β-lactamase or plasmid-mediated AmpC β-lactamase genes, with CTX-M-14 being the most frequent. CTX-M producers from livestock and patients belonged to 22 and 19 different sequence types (STs), respectively, and only three STs were the same. Among the 3GC-resistant E. coli from livestock and farmers, three types of CTX-M producers have shown similar characteristics (CTX-M genotype, ST, PFGE patterns, and antimicrobial susceptibilities) and were identified as clonal isolates shared among their farms. ConclusionsOur study findings indicate that CTX-M-14 is predominant in Japan. No distinct relationship was observed between the 3GC-resistant E. coli isolated from livestock and patients; however, some clonal relatedness was observed between the isolates from livestock and farmers due to their close contact.

Etiology, Clinical Spectrum, Epidemiology, New Developments in Diagnosis and Therapeutic Management of Onychomycosis: An Update

Fungal infections are recognized as an important cause of morbidity as well as mortality, especially in the immune-suppressed subjects worldwide. Onychomycosis is a sporadic fungal infection that can affect any part of the nail unit, including the matrix, bed, and plate. It is caused by a wide variety of fungi that include dermatophytes, yeasts, and non-dermatophyte moulds. Dermatophytes are the most common cause of onychomycosis among the numerous fungi. The disease is mainly sporadic and has been recorded in sexes, all age groups, in rural and urban settings, and developing and developed countries. Onychomycosis affects more than 5% of the world's population today. Distal lateral subungual onychomycosis (DLSO), white superficial onychomycosis (WSO), proximal subungual onychomycosis (PSO), endonyx onychomycosis (EO), and candidal onychomycosis are the five primary subtypes of onychomycosis. The condition can manifest itself in a variety of clinical forms, all of which impact the nails on the fingers and legs. Generalized infections involving both hands have been found on occasion. The infection in immunocompromised patient may cause a serious health problem. A plethora of factors, such as nail trauma, occlusive foot wear, and humidity may predispose to fungal nail infections. Clinical diagnosis should be supported with laboratory findings. Direct microscopic demonstration of the fungal agent in the afflicted nail using the potassium hydroxide procedure and isolation of fungi in pure culture on mycological media, such as Sabouraud dextrose agar, dermatophyte test medium, and Pal sunflower seed agar helps to confirm the diagnosis of onychomycosis. The precise morphology of fungal cultures taken from the clinical specimens of patients can be easily investigated in staining solutions, such a PHOL and Narayan. Direct microscopy in potassium hydroxide is still considered the simplest, quickest, and cheapest way to detect fungal agents in nail scrapings. Onychomycosis medications can be applied locally (amorolfine, ciclopirox, efinaconazole, tavaborole) or taken orally (fluconazole, itraconazole, terbinafine). The cure rate is increased when topical and systemic treatments are used together. Depending on the extent of nail involvement, therapy might last from 3 to 6 months or even longer. It is imperative to manage the risk factors. Hygiene is considered the best prevention strategy of onychomycosis.

Biofilm Formation Status in ESBL-Producing Bacteria Recovered from Clinical Specimens of Patients: A Systematic Review and Meta-Analysis.

Recently, the emergence and spread of extended-spectrum beta-lactamase (ESBL) bacteria have become a global health concern. In addition, the ability to form biofilm due to less impermeability to antibiotics and the horizontal transformation (conjugation) of genes involved in antibiotic resistance have exacerbated the concerns. With a comprehensive meta-analysis, this study evaluated the potential relationship between ESBL and biofilm formation. A literature search was performed using global databases, such as PubMed and Scopus, up to November 2021. We retrieved all relevant documents and selected eligible articles based on inclusion criteria. Finally, the potential association between the biofilm formation capacity and resistance of ESBL-producing bacteria was measured with an odds ratio and a 95% confidence interval. In the present study, 17 articles, including 2,069 Gram-negative isolates, were considered as eligible. The prevalence of biofilm formation in all clinical isolates of ESBL and non-ESBL pathogens was 72.4% (95% CI: 60.7-81.6) and 40.5% (95% CI: 30.2-51.8), respectively. Our results showed a positive relationship between the ability for biofilm formation and conferring antibiotic resistance in ESBL-producing bacteria (OR: 3.35; 95% CI: 1.67-6.74; p-value: 0.001). In general, we showed the rate of biofilm formation to be significantly higher in ESBLproducing strains. Given the current results, the updated therapeutic guidelines should consider the role of biofilm production for optimal therapy, treatment course, and clinical outcomes rather than the recommendation of antimicrobial agents by focusing on the results of the antibiotic susceptibility test.

RBM15 Promates the Proliferation, Migration and Invasion of Pancreatic Cancer Cell Lines.

(1) Background: Pancreatic cancer is increasingly becoming the leading cause of cancer deaths worldwide. In eukaryotic cells, m6A is the most abundant mRNA methylation modification. (2) Methods: We performed a bioinformatic multidimensional analysis using files containing the clinical data of patients and m6A-related gene expression differences downloaded from web-based databases, and performed a statistical analysis and image mapping mainly using R-package. Next, we studied the RBM15 expression in cancer and paracancerous tissues. We then validated these findings in two cell lines by western blot, PCR, Transwell, CCK-8, and EDU animal models. (3) Results: We discovered that RBM15 was highly expressed in pancreatic cancer patients and that it is a significant cause of poor prognosis. Its association with lymphatic T cell family aggregation was established through immune infiltration analysis. A retrospective analysis of data from clinical patient specimens revealed that high expression of RBM15 in patients was closely and positively correlated with preoperative glucose values, gender, and lymphocyte counts. Results from cellular experiments and animal experiments indicated that when the RBM15 gene was silenced, cell proliferation, migration, and metastasis were inhibited. (4) Conclusions: We propose that RBM15 plays a key role in the progression of pancreatic cancer by promoting tumor proliferation, migration and metastasis.

Study of the antibacterial effects of the starch-based zinc oxide nanoparticles on methicillin resistance Staphylococcus aureus isolates from different clinical specimens of patients from Basrah, Iraq.

This study aimed to assess the efficacy of starch-based zinc oxide nanoparticles (ZnO-NPs) against methicillin-resistant Staphylococcus aureus (MRSA) isolates from clinical specimens in Basrah, Iraq. In this cross-sectional study, 61 MRSA were collected from different clinical specimens of patients in Basrah city, Iraq. MRSA isolates were identified using standard microbiology tests, cefoxitin disc diffusion and oxacillin salt agar. ZnO-NPs were synthesized in three different concentrations (0.1 M, 0.05 M, 0.02 M) by the chemical method using starch as the stabilizer. Starch-based ZnO-NPs were characterized using ultraviolet-visible spectroscopy (UV-Vis), X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), energy dispersive X-ray spectroscopy (EDS), and transmission electron microscopy (TEM). The antibacterial effects of particles were investigated by the disc diffusion method. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of the most effective starch-based ZnO-NPs were determined using a broth microdilution assay. The UV-Vis of all concentrations of starch-based ZnO-NPs exhibited a strong absorption band at 360 nm which was characteristic of the ZnO-NPs. XRD assay confirmed the representative hexagonal wurtzite phase of the starch-based ZnO-NPs, and their purity and high crystallinity. The spherical shape with a diameter of 21.56 ± 3.42 and 22.87 ± 3.91 was revealed for the particles by FE-SEM and TEM, respectively. EDS analysis confirmed the presence of zinc (Zn) (61.4 ± 0.54%) and oxygen (O) (36 ± 0.14%). The 0.1 M concentration had the highest antibacterial effects (mean ± SD of inhibition zone = 17.62 ± 2.65 mm) followed by the 0.05 M concentration (16.03 ± 2.24 mm) and the 0.02 M concentration (12.7 ± 2.57 mm). The MIC and the MBC of the 0.1 M concentration were in the range of 25-50 µg/mL and 50-100 µg/mL, respectively. Infections caused by MRSA can be treated with biopolymer-based ZnO-NPs as effective antimicrobials.

Prevalence of carbapenemase-producing organisms among patients admitted to intensive care unit in a tertiary hospital in Benin city, Nigeria

Aim: The study aimed to determine the prevalence of carbapenemase-producing organisms (CPOs) causing clinical infections among intensive care unit (ICU) patients at the University of Benin Teaching Hospital (UBTH), Benin City, Nigeria. Methods: Gram negative bacterial isolates recovered from clinical specimens of patients admitted at the ICU of the hospital during the study period were identified using Microbact 20E and antimicrobial susceptibility tests carried out. Carbapenem resistant isolates were thereafter screened phenotypically for carbapenemase production, CPOs were subsequently screened using PCR for the following genes; NDM, VIM, KPC and OXA-48-like. Results: A total of 64 clinical specimens were received during the study period. Of this number, 26 (40.6%) were culture positive for Enterobacterales (21.9%) and non-fermenters (18.8%). Amikacin showed the best susceptibility profile with 81.5% overall activity against all isolates, the carbapenems showed moderate activity with 66.7% while the third generation cephalosporins were poorly active (37%) against all bacterial isolates. Carbapenemase activity was observed in 9 isolates (14.1%), one isolate of E. cloacae was VIM positive while 62.5% and 25% of CP-P. aeruginosa were NDM and VIM positive respectively. Conclusion: Carbapenemase-producing-P. aeruginosa was the leading cause of infections among ICU patients in Benin City, Nigeria. There is therefore need for surveillance, IPC measures and adherence of antimicrobial stewardship guidelines at institutional and national levels.

Antimicrobial Resistance, Integron Carriage, and Fluoroquinolone Resistance Genes in Acinetobacte baumannii Isolates

Background: Acinetobacte is the leading cause of pneumonia and sepsis in the ICU ward. Accordingly, in the present study, the antibiotic susceptibility pattern, presence, and dissemination of different classes of integrons and fluoroquinolone resistance genes were investigated among A. baumannii isolates. Methods: In this descriptive, cross-sectional study, during a period of 24 months (2018 - 2020), 100 isolates of A. baumannii were isolated from different clinical specimens of patients admitted to the two teaching hospital in Ardabil province in the northwest of Iran. Kirby -Bauer disk diffusion, PCR, and sequencing methods were used for antimicrobial susceptibility testing and gene and mutation verification. Results: The resistance rates to all tested antibiotics were found to be between 78% and 100%. No isolate was resistant to polymyxin B. Multidrug-resistant (MDR) rate among tested clinical isolates was about 99%. The prevalence of class 1, 2, and 3 integrons was found to be 70%, 21%, and 0%, respectively. The aadA1 cassette gene was detected in all class 1 integron-carrying strains. Conclusions: High-level antibiotic resistance and a high prevalence of integrons were observed among these clinical isolates. Our findings highlighted the need for continuous monitoring of resistant isolates.

Biocompatible engineered erythrocytes as plasmonic sensor initiators for high-sensitive screening of non-small cell lung cancer-derived exosomal miRNA in an integrated system

The development of a holistic solution is crucial for exosome-based liquid biopsy, which is a significant advancement from basic research to clinical application for the early and non-invasive diagnosis of disease. However, the challenge of current technology is how to facilitate the separation and quickly connect with the detection. Herein, employing miRNA-155 as a target, a novel integrated concentration and determination system of exosomes (ICDSE) was fabricated for the targeted enrichment of exosomes from the plasma of patients with non-small cell lung cancer and instant downstream analysis of exosomal miRNA. This ICDSE consists of aptamer-engineered erythrocytes with a supramolecular plasmonic biosensor. The streamlined analytical procedure benefited from engineered erythrocytes as an interlinkage, needlessly removing them before extracting total RNA due to the lack of nuclei. With the assistance of a specific aptamer and simple centrifugation, engineered erythrocytes achieved exceptional enrichment of exosomes within 30 min. The LOD of the biosensor for miR-155 approached 2.03 fM due to the substantially high refractive index of the quadruplet supramolecular dendrimer and zirconium metal-organic framework. Impressively, the developed ICDSE successfully isolated and evaluated exosomes from clinical specimens of patients with NSCLC, which can also be promising for other diseases with identifiable exosome signatures. Thus, our ICDSE is expected to have widespread biomedical applications, as it is economical and well-accepted.

The Molecular Characterization of Nosocomial Carbapenem-Resistant Klebsiella pneumoniae Co-Harboring blaNDM and blaOXA-48 in Jeddah

Carbapenem-resistant Klebsiella pneumoniae (CRKP)-associated infections have become a major concern and life-threatening worldwide. Understanding the epidemiology of CRKP using a reliable molecular technology can help to develop an effective infection control policies. In the western region of Saudi Arabia, there are no sufficient data on the prevalence of CRKP and its carbapenem-resistant determinants. Therefore, this study aimed to determine the molecular epidemiology of CRKP and identify the most common carbapenemase genes. In the current study, a total of 191 CRKP isolates were collected and obtained from clinical specimens of patients at King Fahad Armed Forces Hospital (KFAFH), Jeddah, Saudi Arabia. All isolates that were resistant or intermediately susceptible to either of the carbapenem antimicrobials (imipenem, meropenem, or ertapenem) were included. All CRKP showed resistance to ceftazidime, cefepime, and piperacillin/tazobactam, whereas low (14%) and moderate (37.7%) levels of resistance were reported against tigecycline and colistin, respectively. The most common carbapenemase genes identified were blaOXA-48 (n = 157 [82.2%]), followed by blaNDM in 27 (14%) isolates. The blaVIM and blaKPC were reported in only one isolate each and no blaIMP producers were detected among all tested isolates. The high prevalence of OXA-48 among K. pneumoniae isolates reported in the current study may reflect that OXA-48 has become an endemic in Saudi Arabian hospitals. The second major finding was that the identification of CRKP co-harbors both blaNDM and blaOXA-48, and such isolates can be threating for healthcare societies (patients and healthcare workers) due to their high level of resistance to carbapenems. These results suggest that the use of molecular diagnostic methods and proper surveillance programs are required to monitor and control the spread of all multidrug-resistant (MDR) bacteria, including CRKP. Therefore, further research is recommended to expand the study and further analyze the genotyping of the most common clones of CRKP in other hospitals in the western regions of Saudi Arabia.

Mechanisms of linezolid resistance in Staphylococcus capitis with the novel mutation C2128T in the 23S rRNA gene in China

PurposeThe objective of this study was to investigate the molecular characteristics and potential resistance mechanisms of linezolid-resistant (LZR) Staphylococcus capitis isolates from a tertiary hospital in China.MethodsS. capitis isolates were obtained from clinical patient specimens; three of the isolates came from blood cultures and one from the hydrothorax. The agar dilution and E-test methods were used to identify antibiotic resistance. The chloramphenicol-florfenicol resistance (cfr) gene carrier status of the strains was determined by PCR. Whole-genome sequencing (WGS) was used to identify point mutations and L3, L4, and L22 mutations and to study the genetic environment of the cfr gene and the relationships between strains.ResultsThe 4 isolates obtained in this study were all linezolid-resistant Staphylococcus strains. A similar of susceptibility profile pattern was observed in all four S. capitis strains, each of which exhibited a multidrug-resistant phenotype. A potentially novel mutation, C2128T, was identified, and the cfr genes of S. capitis strains were all positive. Additionally, the same mutations (C2128T and G2600T) were identified in all 23S rRNA sequences of the isolates, whereas mutations were lacking in the L3, L4, and L22 ribosomal proteins. The genetic environments surrounding cfr were identical in all four isolates. A schematic diagram of the phylogenetic tree showed that they were closely related to AYP1020, CR01, and TW2795, and a total of seven drug resistance genes were identified in these strains.ConclusionsThe study indicated that the resistance of the Staphylococcus capitis strains to linezolid was caused by multiple mechanisms, and a potential novel mutation, C2128T, that may have an impact on bacterial resistance was identified.