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It is essential to refrain from unnecessary isolation measures indicated for patients identified with multidrug-resistant Gram-negative bacteria (MDR-GNB). To evaluate whether a pro-active follow-up strategy to discontinue isolation measures of patients identified with MDR-GNB (without carbapenemase production) resulted in reduced isolation days during hospitalization, compared to passive follow-up. A comparison was made between active and passive follow-up strategies over a two-year period after first MDR-GNB identification. Patients could be declared negative after two consecutive negative screening cultures. Active follow-up patients received a questionnaire for screening cultures within six months of MDR-GNB identification. Of the 2208 patients included, 1424 patients (64.5%) underwent passive follow-up and 784 patients (35.5%) underwent active follow-up. A significantly higher proportion of active follow-up patients who had sufficient (at least two) screening cultures were declared MDR-GNB negative compared to those with passive follow-up; 66.9% vs 20.6% (P < 0.001) for adult patients and 76.0% vs 17.1% (P < 0.001) for paediatric patients. A comparison between active follow-up patients with sufficient versus those with active follow-up but insufficient cultures revealed a reduction of isolation days for paediatric patients (median 10.6 vs 1.6 days; P = 0.031). Though this difference was not statistically significant for adults (median 5.3 vs 4.2 isolation days), there was a valuable decrease in the number of isolation days for both adult and paediatric patients under active follow-up with sufficient (≥2) cultures, indicating clinical relevance. We recommend an active follow-up strategy for patients identified with an MDR-GNB, to prevent further unneeded infection prevention measures. [ABSTRACT FROM AUTHOR]

Antimicrobial resistance (AMR) is a growing threat to human and animal health. Data are limited on the prevalence of resistant bacteria in pet rabbits. Therefore, we aimed to identify prevalent bacterial infections and AMR profiles among pet rabbits in Hong Kong (HK). Our search of the CityU Veterinary Diagnostic Laboratory (VDL) database found 301 cases of pet rabbits submitted for bacteriologic and antimicrobial susceptibility testing by veterinarians at 20 exotic veterinary clinics across HK between 2019 and 2022. The rabbits were of 8 different breeds and had a median age of 6.5 y, with 54.8% males, 40.2% females, and 5% unspecified. Of the 301 samples received, 168 (55.8%) had positive bacterial growth; 125 (74.4%) had single bacterial isolates, and 43 (25.6%) had mixed cultures. Cultures included Enterococcus faecalis (21.3%) as the most frequently isolated gram-positive bacterium, followed by Streptococcus intermedius (12.5%), and Staphylococcus aureus (11.3%). The most frequently isolated gram-negative bacteria were Pseudomonas aeruginosa (18.1%), followed by Escherichia coli (8.3%), Pasteurella multocida (6.9%), and Klebsiella pneumoniae (4.2%). Approximately 83% of the isolates had acquired resistance to at least one antimicrobial agent, and 49.4% were multidrug-resistant. The isolated bacteria had high levels of resistance to penicillin (69.8%), clindamycin (47.4%), and doxycycline (46.9%). Our findings highlight the high levels of AMR in bacteria isolated from pet rabbit clinical samples in HK; many of these bacteria are zoonotic and pose a public health threat. [ABSTRACT FROM AUTHOR]

Virulence pathways in pathogenic bacteria are regulated by quorum sensing mechanisms, particularly biofilm formation through autoinducer (AI) production and sensing. In this study, the culture filtrate extracted from an edible mushroom, Agaricus subrutilescens , was fractionated to isolate a compound that inhibits biofilm formation. Four gram-negative bacteria (Klebsiella pneumoniae, Escherichia coli, Proteus mirabilis , and Enterobacter cloacae) and two gram-positive bacteria (Enterococcus faecalis and Staphylococcus aureus) were used for the bioassay. The bioassay-guided chromatographic separations of the culture filtrate extract resulted in the isolation of the compound. Further, spectroscopic analyses revealed the identity of the compound as 2,2′-azoxybisbenzyl alcohol (ABA). The minimum inhibitory and sub-inhibitory concentrations of the compound were also determined. Azoxybisbenzyl alcohol was significantly effective in inhibiting biofilm formation in all tested bacteria, with half-maximal inhibitory concentrations of 3–11 µg/mL. Additionally, the bioactivity of ABA was confirmed through the bioassays for the inhibition of exopolysaccharide matrixes and AI activities. [ABSTRACT FROM AUTHOR]

Urinary tract infections (UTIs) can lead to neonatal complications like sepsis, worsened by empirical treatment, contributing to antimicrobial resistance (AMR). This study examined the incidence, etiology, risk factors, and antimicrobial susceptibility of uropathogens in a Neonatal Intensive Care Unit (NICU) in Brazil. Medical records of neonates hospitalized in the NICU from January 2015 to June 2022 were retrospectively analyzed through the National Healthcare Safety Network system. Among 1,474 neonates, 3.9% developed UTI, with an alarming 24-fold increase in incidence from 2015 to 2021. Genitourinary complications (odds ratio = 4.8) were a major risk factor. Of the 71 uropathogens, 74.6% were Gram-negative bacteria (GNB), 21.2% Gram-positive bacteria (GPB), and 4.2% Candida albicans. AMR was notable, with 13.3% of GPB and 20.7% of GNB exhibiting multidrug-resistant (MDR), while 6.6% of GPB and 1.9% of GNB showed extensive drug-resistant (XDR). UTI was associated with prolonged hospitalization (16-59 days). In 57 neonates with UTI, 40.3% had bloodstream infections, elevating the risk of death (odds ratio = 1.8). The study underscores the urgency of implementing infection prevention and control measures in the NICU to curb rising UTI incidences, combat AMR, and mitigate severe complications in critically ill neonates. • UTI incidence soared 24× (2015: 0.1 to 2021: 2.4). • Genitourinary issues: major risk factors. • MDR isolates were found in 20% of GPB and 22.6% of GNB. • K. pneumoniae (38%) dominated, 48.1% were ESBL. • UTI linked to prolonged hospitalization (16-59 days). [ABSTRACT FROM AUTHOR]

The treatment of sepsis caused by multidrug-resistant (MDR) Gram-negative bacterial infections remains challenging. With these pathogens exhibiting resistance to carbapenems and new generation cephalosporins, the traditional antibiotic polymyxin B (PMB) has reemerged as a critical treatment option. However, its severe neurotoxicity and nephrotoxicity greatly limit the clinical application. Therefore, we designed negatively charged high-density lipoprotein (HDL) mimicking nanodiscs as a PMB delivery system, which can simultaneously reduce toxicity and enhance drug efficacy. The negative charge prevented the PMB release in physiological conditions and binding to cell membranes, significantly reducing toxicity in mammalian cells and mice. Notably, nanodisc-PMB exhibits superior efficacy than free PMB in sepsis induced by carbapenem-resistant Acinetobacter baumannii (CRAB) strains. Nanodisc-PMB shows promise as a treatment for carbapenem-resistant Gram-negative bacterial sepsis, especially caused by Acinetobacter baumannii , and the nanodiscs could be repurposed for other toxic antibiotics as an innovative delivery system. Multidrug-resistant Gram-negative bacteria, notably carbapenem-resistant Acinetobacter baumannii , currently pose a substantial challenge due to the scarcity of effective treatments, rendering Polymyxins a last-resort antibiotic option. However, their therapeutic application is significantly limited by severe neurotoxic and nephrotoxic side effects. Prevailing polymyxin delivery systems focus on either reducing toxicity or enhancing bioavailability yet fail to simultaneously achieve both. In this scenario, we have developed a distinctive HDL-mimicking nanodisc for polymyxin B, which not only significantly reduces toxicity but also improves efficacy against Gram-negative bacteria, especially in sepsis caused by CRAB. This research offers an innovative drug delivery system for polymyxin B. Such advancement could notably improve the therapeutic landscape and make a significant contribution to the arsenal against these notorious pathogens. [Display omitted] [ABSTRACT FROM AUTHOR]

With increasing awareness of water sinks as potential sources of outbreaks and transmission of multi-drug resistant (MDR) bacteria in intensive care units (ICUs), there is growing interest in water-free patient care systems. This systematic review reviewed and synthesized available evidence on the effectiveness of sink removal with or without water-free activities in the ICU environment to reduce water-borne healthcare-associated infections. We searched five databases (PubMed, MEDLINE, Scopus, Web of Science and Embase) for studies published from 1st January 1980 to 2nd April 2024 that examined water-less or water-free activities in the ICU to reduce healthcare-associated infections and patient colonization. Of 2075 articles, seven quasi-experimental studies (total: 332 patient beds) met the study selection criteria. Six of these seven studies (85.7%) were based in adult ICUs; one (14%) was in a neonatal ICU. Five of seven sites (71.4%) implemented water-less interventions after an outbreak. Water-free alternatives used included water-less bath products (six of seven; 85.7%), bottled water for consumption (three of seven; 42.9%), oral care (three of seven; 42.9%) and dissolving of oral medication (four of seven; 57.1%), designated 'contaminated' sink outside of patient and medication preparation areas for disposal of wastewater (four of seven; 57.1%). Implicated pathogens studied included MDR Gram-negative bacteria (four of seven; 57.1%), MDR Pseudomonas aeruginosa only (two of seven; 28.6%), and pulmonary non-tuberculous mycobacterium (NTB) (one of seven; 14.3%). Five of seven (71.4%) studies reported outbreak cessation. Preliminary evidence, from a limited number of studies of which the majority were conducted in an outbreak setting, suggest that sink removal and other water-free interventions in the ICU helped terminate outbreaks involving taps and decrease hospital-onset respiratory isolation of pulmonary NTB. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this research is to develop an environmentally friendly antimicrobial dyeing of cotton fabric from the root of Euclea racemosa. Textile phytochemical finishing is in high demand worldwide because of its low toxicity, low pollution, ease of availability, renewability, pharmacological effects and non-carcinogenic properties, as well as its multifunctionality, rapid process stages and potential health benefit. Design/methodology/approach: The cotton fabric was dyed with aqueous extracts of Euclea racemosa root dyes. Dyes were extracted for 20 min at pH 7.43 at room and boiling temperatures with material-to-liquor ratios (MLRs) of 1:5, 1:10, 1:15 and 1:20, altering one variable at a time, and the cotton fabric was colored using a post-mordanting procedure at 50°C with an MLR of 1:20. Using a properly cleaned Petri plate, the colored samples were tested in vitro for antibacterial activity. A spectrophotometer was used to assess color strength and shade depth, as well as wash fastness and annual rubbing fastness tests for both wet and dry. Findings: L* = 36.29, a* = 58.56, b* = 32.46 and K/S = 0.51 were the CIELAB values for dye extracted at boiling temperature. L* = 47.14, a* = 42.23, b* = 49.61 and K/S = 0.38 were the CIELAB values for dye extracted at room temperature. The wash and rubbing fastness of the dyed samples were outstanding and the dyed cotton fabrics were found antibacterial against Gram-negative bacteria Escherichia coli. Originality/value: Dyes derived from the E. racemosa root could be used to develop a new antibacterial cotton fabric dye. [ABSTRACT FROM AUTHOR]

Cascade-reaction containers generating reactive oxygen species (ROS) as an alternative for antibiotic-based strategies for bacterial infection control, require endogenous oxygen-sources and ROS-generation close to or preferably inside target bacteria. Here, this is achieved by cetyltrimethylammonium-chloride (CTAC) assisted in situ metabolic labeling and incorporation of mesoporous SiO 2 -nanoparticles, dual-loaded with glucose-oxidase and Fe 3 O 4 -nanoparticles as cascade-reaction containers, inside bacterial cell walls. First, azide-functionalized d-alanine (D-Ala-N 3) was inserted in cell wall peptidoglycan layers of growing Gram-positive pathogens. In Gram-negatives, this could only be achieved after outer lipid-membrane permeabilization, using a low concentration of CTAC. Low concentrations of CTAC had no adverse effect on in vitro blood clotting or hemolysis nor on the health of mice when blood-injected. Next, dibenzocyclooctyne-polyethylene-glycol modified, SiO 2 -nanoparticles were in situ click-reacted with d-Ala-N 3 in bacterial cell wall peptidoglycan layers. Herewith, a two-step cascade-reaction is facilitated inside bacteria, in which glucose-oxidase generates H 2 O 2 at endogenously-available glucose concentrations, while subsequently Fe 3 O 4 -nanoparticles catalyze generation of •OH from the H 2 O 2 generated. Generation of •OH inside bacterial cell walls by dual-loaded mesoporous SiO 2 -nanoparticles yielded more effective in vitro killing of both planktonic Gram-positive and Gram-negative bacteria suspended in 10 % plasma than SiO 2 -nanoparticles solely loaded with glucose-oxidase. Gram-positive or Gram-negative bacterially induced sepsis in mice could be effectively treated by in situ pre-treatment with tail-vein injected CTAC and d-Ala-N 3 , followed by injection of dual-loaded cascade-reaction containers without using antibiotics. This makes in situ metabolic incorporation of cascade-reaction containers as described attractive for further investigation with respect to the control of other types of infections comprising planktonic bacteria. In situ metabolic-incorporation of cascade-reaction-containers loaded with glucose-oxidase and Fe 3 O 4 nanoparticles into bacterial cell-wall peptidoglycan is described, yielding ROS-generation from endogenous glucose, non-antibiotically killing bacteria before ROS inactivates. Hitherto, only Gram-positives could be metabolically-labeled, because Gram-negatives possess two lipid-membranes. The outer membrane impedes direct access to the peptidoglycan. This problem was solved by outer-membrane permeabilization using a quaternary-ammonium compound. Several studies on metabolic-labeling perform crucial labeling steps during bacterial-culturing that in real-life should be part of a treatment. In situ metabolic-incorporation as described, can be applied in well-plates during in vitro experiments or in the body as during in vivo animal experiments. Surprisingly, metabolic-incorporation proceeded unhampered in blood and a murine, bacterially-induced sepsis could be well treated. [Display omitted] [ABSTRACT FROM AUTHOR]

Gastrointestinal adenocarcinomas are often reported in South American camelids (SAC). We describe here cases of gastroduodenal adenocarcinoma in an adult alpaca (Vicugna pacos) and a llama (Llama glama); both SACs were anorectic and lethargic before death. At autopsy, a prominent and firm caudal C3-pyloric-duodenal junction with stricture and ulceration was present in both animals, as were hemorrhages in various organs and hydrothorax. Microscopically, scattered nests, cords, and tortuous acini of neoplastic epithelial cells were embedded in desmoplastic stroma and invaded the submucosa and muscle layers of the gastroduodenal junction. The mucosa was necrotic, with gram-negative rods in the alpaca and colonies of gram-positive cocci in the llama. No tumor metastases were observed. The neoplastic cells immunolabeled for pancytokeratin. Escherichia coli was isolated from the alpaca and Streptococcus lutetiensis from the llama; septicemia was the cause of death in both animals. Although adenocarcinomas arising from gastric compartments and intestinal segments have been reported in SACs, adenocarcinoma of the caudal C3-pyloric-duodenal junction has not been reported previously in these species, to our knowledge. [ABSTRACT FROM AUTHOR]

Stenotrophomonas maltophilia is an emerging multi-drug resistant, opportunistic pathogen in the neonatal intensive care unit (NICU). In this study, we aimed to assess the incidence, clinical features, antibiotic susceptibility, and treatment options of S. maltophilia infection among the healthcare-associated infections (HAIs) in the neonatal unit. In this study , the patients who were hospitalized in the NICU between January 2020 and December 2021 with S. maltophilia isolated from clinical samples were included. Demographic, clinic features, and microbiological findings of the patients were retrospectively evaluated by using the medical records. The samples (lower respiratory tract, urine, peritoneal fluid) were first examined microscopically by gram preparation and cultured. Antibiotic susceptibility tests were performed according to the recommendations of The European Committee on Antimicrobial Susceptibility Testing (EUCAST) for TMP-SMX. S. maltophilia was isolated in 38 clinical samples of the 20 patients who were hospitalized at the NICU between January 2020 and December 2021. A total of 40 % (n = 8) of samples from different patients were accepted as colonization. Ventilator-associated pneumonia was determined in 55 % (n = 11), and urinary tract infection in 5 % (n = 1). S. maltophilia -associated bacteremia was not detected in any of the cases. The TMP-SMX susceptibilities of the strains were as it follows: 3 (15 %) were resistant (R), 7 (28 %) were susceptible (S), and 10 (47 %) were susceptible-increased exposure (I). Three of these patients were given dual antibiotics therapy (levofloxacin plus TMP-SMX) and nine of them were given only TMP-SMX. The most common hospital-acquired infectious agents are Gram negative microorganisms (51 %), followed by coagulase negative staphylococci (CNS), Staphylococcus aureus (24 %) and S. maltophilia (24 %). Increasing TMP-SMX resistance and specific drug and dosage-related problems in the neonatal unit are important problems in treatment management. [ABSTRACT FROM AUTHOR]

Citrobacter braakii (C. braakii) is an anaerobic, gram‐negative bacterium that has been isolated from the environment, food, and humans. Infection by C. braakii has been associated with acute mucosal inflammation in the intestine, respiratory tract, and urinary tract. However, the pathogenesis of C. braakii in the gastric mucosa has not yet been clarified. In this study, the bacterium was detected in 35.5% (61/172) of patients with chronic gastritis (CG) and was closely associated with the severity of mucosal inflammation. Citrobacter braakii P1 isolated from a patient with CG exhibited urease activity and acid resistance. It contained multiple secretion systems, including a complete type I secretion system (T1SS), T5aSS and T6SS. We then predicted the potential pilus‐related adhesins. Citrobacter braakii P1 diffusely adhered to AGS cells and significantly increased lactate dehydrogenase (LDH) release; the adhesion rate and LDH release were much lower in HEp‐2 cells. Strain P1 also induced markedly increased mRNA and protein expression of IL‐8 and TNF‐α in AGS cells, and the fold increase was much higher than that in HEp‐2 cells. Our results demonstrate proinflammatory and cytotoxic role of C. braakii in gastric epithelial cells, indicating the bacterium is potentially involved in inducing gastric mucosa inflammation. [ABSTRACT FROM AUTHOR]

Imipenem/relebactam (IMR) was approved for patient use in Taiwan in 2023. We evaluated the in vitro susceptibility of recent Gram-negative pathogens collected in Taiwan hospitals to IMR and comparators with a focus on carbapenem-resistant and KPC-carrying non- Morganellaceae Enterobacterales (NME), and carbapenem-resistant Pseudomonas aeruginosa (CRPA). From 2018 to 2021, eight hospitals in Taiwan each collected up to 250 consecutive, aerobic or facultative, Gram-negative pathogens per year from patients with bloodstream, intraabdominal, lower respiratory tract, and urinary tract infections. MICs were determined using Clinical Laboratory Standards Institute (CLSI) broth microdilution. Most isolates that were IMR-, imipenem-, or ceftolozane/tazobactam-nonsusceptible were screened for β-lactamase genes by PCR or whole-genome sequencing. Ninety-eight percent of NME (n = 5063) and 94% of P. aeruginosa (n = 1518) isolates were IMR-susceptible. Percent susceptible values for non-carbapenem β-lactam comparators, including piperacillin/tazobactam, were 68–79% for NME isolates, while percent susceptible values for all β-lactam comparators, including meropenem, were 73–81% for P. aeruginosa. IMR retained activity against 93% of multidrug-resistant (MDR) NME and 70% of MDR P. aeruginosa. Sixty-five percent of carbapenem-resistant NME and 81% of KPC-positive NME (n = 80) were IMR-susceptible. IMR inhibited 70% of CRPA (n = 287). Fifty percent of IMR-nonsusceptible NME tested for β-lactamase carriage had an MBL or OXA-48-like enzyme, whereas most (95%) IMR-nonsusceptible P. aeruginosa examined did not carry acquired β-lactamase genes. Based on our in vitro data, IMR may be a useful option for the treatment of hospitalized patients in Taiwan with infections caused by common Gram-negative pathogens, including carbapenem-resistant NME, KPC-positive NME, and CRPA. [ABSTRACT FROM AUTHOR]

Objective: This study aims to determine the pattern of germs and antibiotic sensitivity in septic patients treated with culture-based antibiotics. Design: This study was designed for observational- descriptive retrospective. Setting: The medical record of Dr. Wahidin Sudirohusodo Hospital from January 2018 to January 2022. Patient and participants: All patients who were diagnosed with sepsis and had data on bacterial culture and treatment with antibiotics. Interventions: We took blood culture data of patients diagnosed with sepsis from medical records. Measurement and results: The pattern of bacteria found was Gram-negative bacteria, with the most abundant bacteria being Burkholderia cepacia (37.93%), followed by Acinetobacter baumannii (24.14%), and Klebsiella pneumoniae (10.34%). The highest antibiotic sensitivity was obtained for tigecycline with 88.89% followed by levofloxacin with 78.57%. The lowest antibiotic sensitivity was found in ampicillin, ampicillin/ sulbactam, and cefoperazone/sulbactam as much as 0% or all of these antibiotics showed results that were resistant to culture results. Conclusions: Gram-negative bacteria are the main cause of septic patients with varying antibiotic sensitivity depending on the type of antibiotic used. [ABSTRACT FROM AUTHOR]

Endotoxins, products of Gram-negative bacteria, are the primary cause of blood-brain barrier (BBB) damage. In the present study, we aimed to investigate the possible neuroprotection mechanisms of melatonin on BBB damage induced by endotoxemia. Adult, female Sprague-Dawley rats (n = 42) were separated into four random groups as a control group and three treatment groups. Lipopolysaccharide (7,5 mg/kg/day) was administrated for a single dose to generate a 24-hour sepsis model on rats. Melatonin (10 mg/kg/day) was treated a week before sepsis. Afterward, the dissected brain tissues were examined by histopathological, biochemical, and molecular analyses. LPS caused weight loss in the groups. As a result, degenerated neurons with cytoplasmic vacuoles and irregular pyknotic nuclei, pale stained necrotic neurons, and vascular congestion were observed in LPS-exposed rats. However, MEL decreased the number of degenerated neurons in treated groups. MEL treatment increased ZO1 and Occludin immunoreactivity while decreasing TLR4 in brain tissues. MEL effect on protein expression was recorded for ZO1 increase and TLR4 decrease in brain tissue compared to LPS groups. MEL also decreased MDA levels in brain tissue. MEL recovered the degenerative damage of sepsis by contributing to blood-brain barrier integrity, and by decreasing inflammation, thus the neuroprotective effects of MEL might provide an experimental basis for clinical applications. [ABSTRACT FROM AUTHOR]

Objective: This study aims to determine the pattern of germs and antibiotic sensitivity in septic patients treated with culture-based antibiotics. Design: This study was designed for observational-descriptive retrospective. Setting: The medical record of Dr. Wahidin Sudirohusodo Hospital from January 2018 to January 2022. Patient and participants: All patients who were diagnosed with sepsis and had data on bacterial culture and treatment with antibiotics. Interventions: We took blood culture data of patients diagnosed with sepsis from medical records. Measurement and results: The pattern of bacteria found was Gram-negative bacteria, with the most abundant bacteria being Burkholderia cepacia (37.93%), followed by Acinetobacter baumannii (24.14%), and Klebsiella pneumoniae (10.34%). The highest antibiotic sensitivity was obtained for tigecycline with 88.89% followed by levofloxacin with 78.57%. The lowest antibiotic sensitivity was found in ampicillin, ampicillin/sulbactam, and cefoperazone/sulbactam as much as 0% or all of these antibiotics showed results that were resistant to culture results. Conclusions: Gram-negative bacteria are the main cause of septic patients with varying antibiotic sensitivity depending on the type of antibiotic used. [ABSTRACT FROM AUTHOR]

Patients already colonized with multidrug-resistant (MDR) Gram-negative bacteria (GNB) on admission to critical care units may be an important source of transmission of these bacteria in hospitals. We sought to determine the prevalence of MDR GNB colonization in patients, staff and the ward environment and to assess the risk factors for colonization of patients in wards. The study was conducted from April 2021 to July 2021 in a teaching hospital in Ghana. MDR GNB were isolated from rectal, and hand swabs were taken from patients on admission and after 48 h. Swabs from HCW's hands and the ward environment were also taken. Risk factors for colonization with MDR GNB were assessed using univariate and multivariate analysis. MDR GNB rectal colonization rate among patients was 50.62% on admission and 44.44% after 48 h. MDR GNB were isolated from 6 (5.26%) and 24 (11.54%) of HCW's hand swabs and environmental swabs, respectively. Previous hospitalization (p -value = 0.021, OR, 95% CI= 7.170 (1.345–38.214) was significantly associated with colonization by MDR GNB after 48 h of admission. Age (21–30 years) (p -value = 0.022, OR, 95% CI = 0.103 (0.015–0.716) was significantly identified as a protective factor associated with a reduced risk of rectal MDR GNB colonization. The high colonization of MDR GNB in patients, the carriage of MDR GNB on HCW's hands, and the contamination of hospital environments highlights the need for patient screening and stringent infection prevention and control practices to prevent the spread of MDR GNB in hospitals. [ABSTRACT FROM AUTHOR]

Early detection of antimicrobial-resistant microorganisms is crucial to prevent subsequent invasive infections and contain their spread in the Neonatal Intensive Care Unit (NICU). This study aims to investigate the association between intestinal colonization (IC) by Gram-negative bacteria and the risk of bloodstream infection (BSI) in critically ill neonates. Data from the electronic medical records of 678 newborns admitted to a NICU Brazilian between 2018 and 2022 were retrospectively analyzed. Participants were monitored by the National Health Security Network. Among neonates, 6.9 % had IC (56.9 % attributed to Acinetobacter baumannii); of these, 19.1 % developed BSI (66.7 % by Staphylococcus spp.). Within the A. baumannii colonization, 34.5 % occurred during an outbreak in September 2021. Colonized individuals had a longer mean length of stay (49.3 ± 26.4 days) and higher mortality rate (12.8 %) compared to non-colonized individuals (22.2 ± 16.9 days; 6.7 %, respectively). Previous use of antimicrobials and invasive devices significantly increased the risk of colonization. Colonization by drug-resistant microorganisms, along with the occurrence of BSI, was associated with increased mortality and reduced survival time. IC contributed to the incidence of BSI, leading to more extended hospital stays and higher mortality rates. Its early detection proved to be essential to identify an outbreak and control the spread of resistant microorganisms within the NICU. [ABSTRACT FROM AUTHOR]

The bacterial ATP-competitive GyrB/ParE subunits of type II topoisomerase are important anti-bacterial targets to treat super drug-resistant bacterial infections. Herein we discovered novel pyrrolamide-type GyrB/ParE inhibitors based on the structural modifications of the candidate AZD5099 that was withdrawn from the clinical trials due to safety liabilities such as mitochondrial toxicity. The hydroxyisopropyl pyridazine compound 28 had a significant inhibitory effect on Gyrase (GyrB, IC 50 = 49 nmol/L) and a modest inhibitory effect on Topo IV (ParE, IC 50 = 1.513 μmol/L) of Staphylococcus aureus. It also had significant antibacterial activities on susceptible and resistant Gram-positive bacteria with a minimum inhibitory concentration (MIC) of less than 0.03 μg/mL, which showed a time-dependent bactericidal effect and low frequencies of spontaneous resistance against S. aureus. Compound 28 had better protective effects than the positive control drugs such as DS-2969 (5) and AZD5099 (6) in mouse models of sepsis induced by methicillin-resistant Staphylococcus aureus (MRSA) infection. It also showed better bactericidal activities than clinically used vancomycin in the mouse thigh MRSA infection models. Moreover, compound 28 has much lower mitochondrial toxicity than AZD5099 (6) as well as excellent therapeutic indexes and pharmacokinetic properties. At present, compound 28 has been evaluated as a pre-clinical drug candidate for the treatment of drug-resistant Gram-positive bacterial infection. On the other hand, compound 28 also has good inhibitory activities against stubborn Gram-negative bacteria such as Escherichia coli (MIC = 1 μg/mL), which is comparable with the most potent pyrrolamide-type GyrB/ParE inhibitors reported recently. In addition, the structure–activity relationships of the compounds were also studied. A novel pyrrolamide-type GyrB/ParE inhibitor against drug-resistant bacterial infection with excellent pharmacological activity and druggability was discovered by the structural modifications of the AZD5099 which was withdrawn from clinical trials. [Display omitted] [ABSTRACT FROM AUTHOR]

Background The presence of drug-resistant Gram-negative pathogenic bacteria and Extended Spectrum P-Lactamase Producers (ESBLs) in hospital associated fomites like door handles can serve as vehicles in transmission and may be the key factor in epidemiology of ESBL producing bacterial infection not only in a hospital setting but also in the community. The aim of this study was to determine the prevalence of ESBLs and antibiotic resistance of Gram-Negative pathogenic Bacteria isolated from door-handles in two selected hospitals in Pokhara Metropolitan City, Nepal. The study was conducted in selected hospitals in Pokhara Metropolitan City, Western Nepal. A cross-sectional study design was used. The hospitals were selected randomly. A total of 100 swab samples were taken from door-handles. Isolation and identification of bacteria were done using standard microbiological procedures. An antibiotic susceptibility test, screening and confirmation of ESBLs were performed using the Clinical Laboratory Standard Institute's guidelines. Results Out of the 100 swab samples cultured, 96 (96%) showed bacterial growth. A total of one hundred and forty isolates were isolated in this study which were further identified based on cultural, morphological and biochemical characteristics. The study also found that door handles/knobs had higher level of contamination in Outpatient Departments (OPDs), Emergency, Laboratory, General wards and Toilets, in that order as compared to Radiology Room, Staff rooms, Intensive Care Unit and Operation Theatre which were lower. The level of contamination varies depending on the traffic exposure and the environment. The most prevalent Gram-negative bacteria identified was Escherichia coli 28.85%, followed by Klebsiella spp 21.15%, Pseudomonas aeruginosa 15.38%, Proteus spp 11.54%, Enterobacter spp 9.62%, Acenetobacter spp 7.69%, Citrobacter spp 5.77%. The most effective drug of choice was Amikacin, Nitrofurantoin, Norfloxacin, Ciprofloxacin, Tetracycline and Imipenem for many Gram-negative isolates. The overall prevalence of ESBLs in this study was 27.14%. Out of total 15 Escherichia coli isolated, 11(73.3%), Klebsiella spp 9/11 (81.8%); Pseudomonas spp 7/8 (87.5%), Proteus spp 4/6 (66.6%); Enterobacter spp 3/5 (60%), Acenetobacter spp 3/4 (75%) and Citrobacter spp 1/3 (33.3%) were found to be Extended P-Lactamase Producers (ESBLs). Conclusion The isolation of of pathogenic Gram-negative bacteria and ESBLs in hospital environments and subsequent detection of high drug resistance patterns indicates a potentially serious public health challenge that strengthens the need for the effective and routine cleaning of door-handles in hospitals. [ABSTRACT FROM AUTHOR]

Background: Chronic rhinosinusitis with nasal polyposis (CRSwNP) is a multifactorial disease with no known single cause, but it is thought that bacteria play a role in the disease process. Objective: This pilot study aims to assess the longitudinal effect of corticosteroid therapy on sinus microbiota in chronic rhinosinusitis patients with nasal polyposis (CRSwNP). Methods: A longitudinal prospective case-control study was done on patients with CRSwNP and healthy controls. Patients with CRSwNP were randomly allocated to a corticosteroids and antibiotics treatment group (CRSwNP-SA) or a corticosteroid-only treatment group (CRSwNP-S). Data were collected at three-time points (before treatment, 1, and 3 months after treatment). Specimens were cultured and matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) mass spectrometry (MS) was used as a bacterial detection method. Results: Data from 29 patients with CRSwNP (16 CRSwNP-SA and 13 CRSwNP-S) was compared to 15 healthy subjects. Patients reported significant symptom improvement initially (1 month), but not in the long-term (3 months). This result was found in both treatment groups, whether or not antibiotics were used. After 3 months from treatment, the prevalence of Corynebacterium genera tended to increase in the CRSwNP-SA, while Staphylococcus and Gram-negative genera (Pseudomonas) tended to increase in the CRSwNP-S. Smoking, aspirin sensitivity, and previous endoscopic sinus surgery were found to be co-factors significantly associated with the response to systemic corticosteroid therapy. Conclusion: In this pilot study, both treatment options were effective to improve symptoms in the short-term but not in the long-term, and were not linked to any clear sinus microbiota response. As a result, this study supports the avoidance of systemic antibiotics without evidence of active infection. [ABSTRACT FROM AUTHOR]

Five pigs experimentally infected with Actinobacillus pleuropneumoniae serovar 15 isolated in our previous study were pathologically examined. One pig died at 2 days post inoculation (dpi) and four pigs were euthanized at 7 dpi. Autopsy revealed fibrinohemorrhagic pleuropneumonia in all pigs. Histopathologically, the lesions were characterized by extensive hemorrhage and necrosis, fibrin deposition, and multifocal abscesses composed of numerous neutrophils including oat cells and numerous Gram-negative bacilli. In one survived pig, asteroid body formation was confirmed in the lung. The bacteria within the abscesses and asteroid bodies were immunohistochemically positive for antiserum raised against A. pleuropneumoniae serovar 15. This is the first report describing porcine pleuropneumonia with asteroid bodies in a pig experimentally infected with A. pleuropneumoniae serovar 15. [ABSTRACT FROM AUTHOR]

The emergence of antimicrobial resistance raises the fear of untreatable diseases. Antimicrobial resistance is a multifaceted and dynamic phenomenon that is the cumulative result of different factors. While Gram-positive pathogens, such as methicillin-resistant Staphylococcus aureus and Clostridium difficile, were previously the most concerning issues in the field of public health, Gram-negative pathogens are now of prime importance. The World Health Organization's priority list of pathogens mostly includes multidrug-resistant Gram-negative organisms particularly carbapenem-resistant Enterobacterales, carbapenem-resistant Pseudomonas aeruginosa, and extensively drug-resistant Acinetobacter baumannii. The spread of Gram-negative bacterial resistance is a global issue, involving a variety of mechanisms. Several strategies have been proposed to control resistant Gram-negative bacteria, such as the development of antimicrobial auxiliary agents and research into chemical compounds with new modes of action. Another emerging trend is the development of naturally derived antibacterial compounds that aim for targets novel areas, including engineered bacteriophages, probiotics, metal-based antibacterial agents, odilorhabdins, quorum sensing inhibitors, and microbiome-modifying agents. This review focuses on the current status of alternative treatment regimens against multidrugresistant Gram-negative bacteria, aiming to provide a snapshot of the situation and some information on the broader context. [ABSTRACT FROM AUTHOR]

Copyright of Chemical Industry / Hemijska Industrija is the property of Association of Chemical Engineers and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

To evaluate the clinical utility of metagenomic next-generation sequencing (mNGS) for the diagnosis of central nervous system infections (CNSI). Cerebrospinal fluid (CSF) from 54 patients who were high-level clinical suspicion of CNSI was collected and sent for mNGS and conventional tests from January 2019 to March 2022. Twenty out of 54 patients were diagnosed with CNSI and 34 non-CNSI. Among the 34 non-CNSI, one was false positive by mNGS. Among the 20 CNSI, 11 had presumed viral encephalitis and/or meningitis, 5 had presumed bacterial meningitis, 2 had presumed TMB, 1 had Crytococcus meningitis and 1 had neurosyphilis. The sensitivity of viral encephalitis and/or meningitis was 0.73 (8/11); 10 virus were detected; 9/10 was dsDNA; 1/10 was ssRNA. SSRN ranged from 1 to 13. The accuracy rate was 0.4, the accuracy rate was positively correlated with SSRN (r = 0.738, P = 0.015), SSRN ≥ 1, the accuracy rate was 0.4; SSRN ≥ 3, the accuracy rate was 0.66; SSRN ≥ 4, the accuracy rate was 0.75; SSRN ≥ 6, the accuracy rate was 1. The sensitivity of bacterial meningitis was 1. Seven kinds of bacteria were detected, among which 3/7 were gram positive, 3/7 were gram negative, and 1/7 was infected NTM (nontuberculous mycobacteria). The accuracy rate was 0.43 (3/7). The sensitivity of TBM was 0.66 (2/3), the accuracy rate was 1. The sensitivity of Crytococcus meningitis was 1, the accuracy rate was 0.5. PPV (positive predictive value) of mNGS was 0.94, NPV (negative predictive value) of mNGS was 0.89, specificity was 0.97 and sensitivity was 0.8. The AUG for CSF mNGS diagnosis of CNSI was 0.89 (95% CI = 0.78–0.99) Headache, meningeal irritation sign and image of meninges abnormal were correlated with the sensitivity of mNGS (r = 0.451, 0.313, 0.446; p = 0.001, 0.021, 0.001); CSF Glucose and CSF Chloride were negatively correlated with sensitivity of mNGS (r = -0.395, −0.462; p = 0.003, ＜ 0.001). mNGS is a detection means with high sensitivity, wide coverage and strong timeliness, which can help clinicians to identify the pathogen diagnosis quickly, conduct targeted anti-infection treatment early and reduce antibiotic abuse. The pathogen which causing low CSF Glucose, low CSF Chloride or meninges infections was more likely to be detected by mNGS. It may be related to growth and structural characteristics of the pathogen and blood–brain barrier damage. [ABSTRACT FROM AUTHOR]

Copyright of Salud Uninorte is the property of Fundacion Universidad del Norte and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Biomédica: Revista del Instituto Nacional de Salud is the property of Instituto Nacional de Salud of Colombia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Corynebacterium glutamicum AJ1511 and Escherichia coli BW25113 strains were compared in terms of resistance to sarcosine (N-methylglycine). The E. coli strain was more sensitive to sarcosine than C. glutamicum, especially when grown in minimal medium. Growth inhibition of the BW25113 strain in minimal M9 medium containing 0.5 m sarcosine was overcome by the addition of glycine. Inactivation of the glycine cleavage (GCV) system (gcvP) as well as the removal of its activator (gcvA) in BW25113 cells increased the threshold for sarcosine inhibition up to 0.75 m. Activation of the promoter of the E. coli gcvTHP operon by 0.1-0.4 m sarcosine added to M9 medium was demonstrated in vivo using dasherGFP as the reporter. Sensitivity to sarcosine on glucose minimal medium is suggested to be a characteristic of Gram-negative bacteria with GcvA/GcvR regulation of the GCV system. [ABSTRACT FROM AUTHOR]

To investigate the distribution and antimicrobial susceptibility of causative microorganisms recovered from patients with intra-abdominal infections (IAIs). A total of 2,926 bacterial and fungal strains were identified in samples collected from 1,679 patients with IAIs at the Peking Union Medical College Hospital between 2011 and 2021. Pathogenic bacteria and fungi were identified using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Antimicrobial susceptibility testing (AST) was performed using the VITEK 2 compact system and the Kirby–Bauer method. AST results were interpreted based on the M100-Ed31 clinical breakpoints of the Clinical and Laboratory Standards Institute. Of the 2,926 strains identified, 49.2%, 40.8%, and 9.5% were gram-negative bacteria, gram-positive bacteria, and fungi, respectively. Escherichia coli was the most prevalent pathogen in intensive care unit (ICU) and non-ICU patients; however, a significant decrease was observed in the isolation of E. coli between 2011 and 2021. Specifically, significant decreases were observed between 2011 and 2021 in the levels of extended-spectrum β-lactamase (ESBL)-producing E. coli (from 76.9% to 14.3%) and Klebsiella pneumoniae (from 45.8% to 4.8%). Polymicrobial infections, particularly those involving coinfection with gram-positive and gram-negative bacteria, were commonly observed in IAI patients. Moreover, Candida albicans was more commonly isolated from hospital-associated IAI samples, while Staphylococcus epidermidis had a higher ratio in community-associated IAIs. Additionally, AST results revealed that most antimicrobial agents performed better in non-ESBL-producers than in ESBL-producers, while the overall resistance rates (56.9%–76.8%) of Acinetobacter baumanmii were higher against all antimicrobial agents than those of other common gram-negative bacteria. Indeed, Enterococcus faecium , Enterococcus faecalis , S. epidermidis , and S. aureus were consistently found to be susceptible to vancomycin, teicoplanin, and linezolid. Similarly, C. albicans exhibited high susceptibility to all the tested antifungal drugs. The distribution and antimicrobial susceptibility of the causative microorganisms from patients with IAIs were altered between 2011 and 2021. This finding is valuable for the implementation of evidence-based antimicrobial therapy and provides guidance for the control of hospital infections. [ABSTRACT FROM AUTHOR]

Copyright of Revista Veterinaria is the property of Universidad Nacional del Nordeste and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Arquivos Brasileiros de Oftalmologia is the property of Arquivos Brasileiros de Oftalmologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A series of new monobactam sulfonates is continuously synthesized and evaluated for their antimicrobial efficacies against Gram-negative bacteria. Compound 33a (IMBZ18G) is highly effective in vitro and in vivo against clinically intractable multi-drug-resistant (MDR) Gram-negative strains, with a highly druglike nature. The checkerboard assay reveals its significant synergistic effect with β -lactamase inhibitor avibactam, and the MIC values against MDR enterobacteria were reduced up to 4–512 folds. X-ray co-crystal and chemoproteomic assays indicate that the anti-MDR bacteria effect of 33a results from the dual inhibition of the common PBP3 and some class A and C β -lactamases. Accordingly, preclinical studies of 33a alone and 33a ‒avibactam combination as potential innovative candidates are actively going on, in the treatment of β -lactamase-producing MDR Gram-negative bacterial infections. IMBZ18G is highly effective against MDR Gram-negative bacteria, with the dual inhibition on PBP3 and class A and C β -lactamases. IMBZ18G-avibactam combination further broadens the antibacterial application of IMBZ18G. [Display omitted] [ABSTRACT FROM AUTHOR]

Copyright of Cukurova Medical Journal / Çukurova Üniversitesi Tip Fakültesi Dergisi is the property of Cukurova University, Faculty of Medicine and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Konuralp Medical Journal / Konuralp Tip Dergisi is the property of Duzce University Medical School and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

• Preparation of new series of Gemini cationic surfactant. • Evaluating surface and thermodynamic parameters of the prepared amphiphiles. • The different analyses confirm the structure of the prepared amphiphiles. • The prepared amphiphiles were evaluated as antibacterial agents against both gram negative and positive bacteria and fugi. Three Gemini amphiphiles had prepared through reaction of amide of succinic acid with different bromo olefins. Their chemical structure was emphasized different spectroscopic methods. the surface tension measurements were investigated at 20, 40 and 60 °C. The Gemini surfactant with the longest tail clarified enhancement of surface parameters values with elevating mixture temperature. Both (ΔGo ads) & (ΔGo mic) data are negative, providing spontaneously occurrence of adsorption and micellization processes while the positivity of (ΔSo ads) &(ΔSo mic) revealing more order for both processes. Thermodynamic behaviour increases by raising chain length. All of fabricated amphiphiles exhibited antimicrobial activity against bacteria and fungi. [ABSTRACT FROM AUTHOR]

Carbapenemase producing gram-negative bacteria (GNB) has become a huge problem in majority of tertiary care centers worldwide. They are associated with very high morbidity and mortality rates, especially when they cause invasive infections. Therefore, rapid detection of these organisms is very important for prompt and adequate antibiotic therapy as well as infection control. The aim of this study was rapid detection of carbapenemase genes and thereby likely carbapenem resistance, 24–48 hours in advance, directly from the positive-flagged blood culture bottles using CHROMagar and Xpert® Carba-R. Aspirate from positively flagged blood culture bottles was subjected to differential centrifuge. All gram-negative bacilli on gram stain from the deposit were processed in Xpert® Carba-R and inoculated on CHROMagar. The presence of genes and growth on CHROMagar was compared with carbapenem resistance on VITEK-2 Compact. A total of 119 GNB isolates were processed. One or more of the carbapenemase genes were detected in 80 isolates. On comparison with VITEK-2 result, 92 samples showed concordance for carbapenem resistance 48 hours in advance. There was discordance in 21 isolates with 12 major errors and 09 minor errors. The sensitivity of direct Xpert® Carba-R test for rapid detection of carbapenem resistance, 48 hours in advance, was 81.42%. The sensitivity of direct CHROMagar test for accurate detection of carbapenem resistance, 24 hours in advance, was 92.06%. The ability to detect carbapenem resistance with very high accuracy, 48 hours in advance, helps in appropriate antibiotic therapy and implementation of effective infection control practices. [ABSTRACT FROM AUTHOR]

Background: The Ag-NPs by green synthesis has a notable interest because of their eco-friendliness, economic views, feasibility, and applications in a wide range. Herein, native plants of Jharkhand (Polygonum plebeium, Litsea glutinosa, and Vangueria spinosus) were selected for the current work of Ag-NP synthesis and further antibacterial activity. Green synthesis was performed for Ag-NPs using Silver nitrate solution as precursor and the dried leaf extract performs as a reductant and stabilizer here. Result: Visually Ag-NP formation was observed along with a colour change and confirmed by UV-visible spectrophotometry on which an absorbance peak occurs at around 400–450nm. Further characterization was done on DLS, FTIR, FESEM, and XRD. Size around 45–86 nm of synthesized Ag-NPs was predicted through DLS. The synthesized Ag-NPs exhibited significant antibacterial activity against Bacillus subtilis (Gram-positive bacteria) and Salmonella typhi (Gram-negative bacteria). The finest antibacterial activity was disclosed by the Ag-NPs synthesized by Polygonum plebeium extract. The diameter of the zone of inhibition in the bacterial plate measured was 0–1.8 mm in Bacillus and 0–2.2 mm in Salmonella typhi. Protein-Protein interaction study was performed to study the effect of Ag-NPs towards different antioxidant enzyme system of bacterial cell. Conclusion: Present work suggest the Ag-NPs synthesized from P. plebeium were more stable for long term and might have prolonged antibacterial activity. In the future, these Ag-NPs can be applied in various fields like antimicrobial research, wound healing, drug delivery, bio-sensing, tumour/cancer cell treatment, and detector (detect solar energy). Schematic representation of Ag-NPs green synthesis, characterization, antibacterial activity and at the end, in silico study to analyse the mechanism of antibacterial activity [ABSTRACT FROM AUTHOR]

Copyright of Industria Textila is the property of Institutul National de Cercetare-Dezvoltare pentru Textile si Pielarie and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Lipid A is a fragment of lipopolysaccharide (LPS) in gram-negative bacteria such as Escherichia coli and Pseudomonas aeruginosa; hence inhibition of its biosynthesis is one of the plausible ways of preventing such bacteria from growth and thus preventing gastrointestinal diseases caused by Escherichia coli and pseudomonas aeruginosa. This research revolves around the development of antibiotic glyceride derivatives for the inhibition of the biosynthesis of lipid A. To target the enzymes involved in the biosynthesis of lipid A, four N,N-dimethylaminobenzoate moiety containing fatty diglyceride derivatives were synthesized through a multi-step synthetic scheme starting from glycerol. The molecular structure of the targeted molecules and synthesized intermediates in the synthetic scheme were confirmed by detailed structural analysis through 1N-NMR, mass and IR spectroscopic techniques. Antibacterial activity was evaluated against the gram-negative bacteria (Escherichia coli and Pseudomonas aeruginosa). The derivatives also underwent docking analysis on the pdb's of enzymatic catalysts involved in the biosynthesis of lipid A using AutoDock Vina package. All synthesized fatty esters gave good antibacterial activity and binding energy upto -7 kcal/mol in the docking analysis. A structure-property relationship was established between alkyl chain lengths of diglycerides and their resultant binding energies. These molecules and their resultant activity can assist in further designing and retrosynthesis of molecular derivatives of drug molecules with lipid A biosynthesis as target for its inhibition. [ABSTRACT FROM AUTHOR]

This study aimed to examine the antimicrobial susceptibility of bovine mastitis pathogens in Japan and develop criteria for testing antimicrobial susceptibility using the simplified agar disk diffusion (ADD) method that is currently being used in clinical practice. Milk samples from 1,349 dairy cows with clinical mastitis were collected and cultured. The minimum inhibitory concentrations (MICs) of the antimicrobials were determined for 504 strains of 28 bacteria. Of the gram-positive bacteria, most Staphylococcus spp. were susceptible to penicillin G (PCG), kanamycin (KM), oxytetracycline (OTC), cefazolin (CEZ), pirlimycin, enrofloxacin, and marbofloxacin. Streptococcus spp. and Trueperella pyogenes showed resistance to OTC and KM. Most gram-negative bacteria were resistant to OTC and CEZ and particularly susceptible to fluoroquinolones. To develop the criteria for a disk diffusion test of the simplified ADD method, the relationships between MICs and diameters of inhibition zones (DIZs) were analyzed and compared with the conventional method. The susceptibility breakpoints of several antimicrobials were lower for both gram-positive and gram-negative bacteria. Particularly for gram-positive bacteria, the application of the new criteria lowers the breakpoint for PCG, suggesting that the use of PCG instead of CEZ may increase. The results suggest that use of these criteria for the simplified ADD method may lead to appropriate antimicrobial choice and consequently the appropriate use of antimicrobials in clinical practice. [ABSTRACT FROM AUTHOR]

Background: Antimicrobial resistance (AMR) surveillance plays an important role in early detection of resistant strains of pathogens and informs treatments decisions at local, regional and national levels. In 2017, Tanzania developed a One Health AMR Surveillance Framework to guide establishment of AMR surveillance systems in the human and animal sectors. Aim: We reviewed AMR surveillance studies in Tanzania to document progress towards establishing an AMR surveillance system and determine effective strengthening strategies. Methods: We conducted a literature review on AMR studies conducted in Tanzania by searching Google Scholar, PubMed, and the websites of the Tanzania Ministry of Health and the World Health Organization for articles written in English and published from January 2012 to March 2021 using relevant search terms. Additionally, we reviewed applicable guidelines, plans, and reports from the Tanzanian Ministry of Health. Results: We reviewed 10 articles on AMR in Tanzania, where studies were conducted at hospitals in seven of Tanzania's 26 regions between 2012 and 2019. Nine AMR sentinel sites had been established, and there was suitable and clear coordination under 'One Health'. However, sharing of surveillance data between sectors had yet to be strengthened. Most studies documented high resistance rates of Gram-negative bacteria to third-generation cephalosporins. There were few laboratory staff who were well trained on AMR. Conclusion: Important progress has been made in establishing a useful, reliable AMR surveillance system. Challenges include a need to develop, implement and build investment case studies for the sustainability of AMR surveillance in Tanzania and ensure proper use of third-generation cephalosporins. What this study adds: This article adds to the knowledge base of AMR trends in Tanzania and progress made in the implementation of AMR surveillance in human health sector as a contribution to the global AMR initiatives to reduce AMR burden worldwide. It has highlighted key gaps that need policy and implementation level attention. [ABSTRACT FROM AUTHOR]

Antimicrobial resistance in methicillin-resistant Staphylococcus aureus and beta-lactamase-producing Gram-negative bacteria is a global health concern necessitating research and the development of effective antimicrobial agents. This study, conducted in May 2020 in Mwanza, Tanzania, aimed to determine the antibacterial activity of metabolites from soil-isolated Bacillus species against clinical bacterial pathogens. One soil-isolated Bacillus species, identified as Bacillus altitudinis/pumilus complex, showed antibacterial activity against Gram-positive cocci, including a methicillin-resistant S. aureus strain with inducible clindamycin resistance, previously isolated from a patient with osteomyelitis. Bacillus altitudinis/pumilus complex metabolites may be a potential source of antimicrobial agents against multidrug-resistant bacteria. What this study adds: The study supports existing research on the discovery and development of new antimicrobial agents against multi-drug-resistant bacteria. We report the antimicrobial activity of metabolites extracted from soil-isolated Bacillus altitudinis/pumilus complex strains against Gram-positive bacteria, including a methicillin-resistant Staphylococcus aureus strain with inducible clindamycin resistance. [ABSTRACT FROM AUTHOR]

Healthcare-associated infections (HCAIs) caused by extended spectrum β-lactamase-producing Gram-negative bacteria (ESBL-GNB) increase morbidity and mortality. This cross-sectional study characterised ESBL genes (bla CTX-M, bla TEM and bla SHV) among 30 ceftriaxone-resistant GNB causing HCAIs between January 2022 and July 2022 by multiplex polymerase chain reaction assay at the zonal referral hospital in Mwanza, Tanzania. Twenty-five (83.3%) had at least one ESBL gene, of which 23/25 (92.0%) carried the bla CTX-M gene. Seventy-two percent (18/25) of the GNB-ESBL isolates carried more than one ESBL gene, of which the majority (88.8%; n = 16/25) carried the bla CTX-M and bla TEM genes. Extended spectrum β-lactamase genes, particularly bla CTX-M, are common among ceftriaxone-resistant GNB causing HCAIs. What this study adds: This study revealed the distribution of genes (bla CTX-M, bla TEM and bla SHV) coding for ESBL production among ceftriaxone resistant GNB causing HCAIs However, all ESBL producing GNB were susceptible towards ceftriaxone-sulbactam indicating that ceftriaxone-sulbactam may be empirically prescribed for treating patients with HCAIs. [ABSTRACT FROM AUTHOR]

Copyright of Brazilian Journal of Biology is the property of Instituto Internacional de Ecologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Brazilian Journal of Biology is the property of Instituto Internacional de Ecologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Brazilian Journal of Biology is the property of Instituto Internacional de Ecologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)