Common Gram-positive Bacteria Research Articles

Clinical validation of the two-point method for predicting vancomycin AUC based on peak and trough plasma concentrations.

Vancomycin area under the curve/minimum inhibitory concentration (AUC/MIC) has been proposed as a therapeutic drug monitoring (TDM) target to dose vancomycin. It is time-consuming to estimate AUCs using traditional methods. A two-point trough-peak method is more straightforward for calculating the vancomycin AUC. However, the technique and the AUC/MIC target have not been validated in Chinese patients. To compare the clinical outcomes of vancomycin therapy in Chinese older adults (aged > 60years) between the trough-only and the two-point peak-trough AUC TDM approaches. The patients were divided into study and control groups according to TDM approaches. A trough-based TDM was used in the control group (target trough level 15-20mg/L). Stanford University has provided a method to predict vancomycin AUC using peak-valley concentration alone (two-point method). A two-point trough-peak TDM approach was employed in the study group (target AUC/MIC ≥ 400). The effect of vancomycin was evaluated in terms of clinical findings, laboratory values, and bacteriologic responses. The effects of treatment and kidney functions were compared between the two groups. A total of 389 patients met the study inclusion criteria, and 189 were excluded based on the exclusion criteria. Of the 200 patients, 80 received the two-point TDM approach (the study group), and 120 were monitored using the trough-based approach (the control group). The average age was 69.8 ± 7.1years. Staphylococcus aureus (34%) was the most common Gram-positive bacteria. No vancomycin-related nephrotoxicity was observed in either group. The percentages of patients with an excellent response to vancomycin therapy were significantly higher in the study group than in the control group, 90% (72/80) versus 73.3% (88/120),P = 0.0039. The two-point peak-trough method is practical for obtaining vancomycin AUC. The AUC/MIC ≥ 400 target demonstrates treatment effectiveness and safety in older Chinese patients.

The Prevalence of Malaria and Bacteremia Co-Infections among Febrile Patients: A Systematic Review and Meta-Analysis.

Comprehensive data on the relative contribution of bacteremia to malaria outcomes in a large number of participants are lacking. Therefore, we collated data on the co-existence of malaria and bacteremia in the literature to provide evidence-based information for future studies investigating the clinical significance of this co-infection. The study protocol was registered at PROSPERO (ID: CRD42021287971). Relevant studies were identified from PubMed, Web of Science, and Scopus. The pooled prevalence of (1) co-existent malaria and bacteremia among febrile patients, (2) the pooled prevalence of bacteremia among patients with malaria, (3) the probability of co-infection, and (4) the pooled prevalence of deaths were estimated by the random-effects model. Fifty-one studies involving 1583 cases of co-infection were included in the analyses. Typhoidal Salmonella spp. and Staphylococcus aureus were the most common Gram-negative and Gram-positive bacteria, respectively. The prevalence of co-existent malaria and bacteremia among febrile patients was 1.9% (95% confidence interval (CI) = 1.5–2.2%, I2 = 96.64%, 31 studies). The prevalence of bacteremia among patients with malaria was 7.6% (95% CI = 6.7–8.7%, and I2 = 96.68%, 43 studies). Co-infection by malaria and bacteremia did not occur by chance (p = 0.024, odds ratio = 0.64, 95% CI = 0.43–0.94, and I2 = 95.7%, 29 studies). The pooled prevalence of deaths among patients with co-infection was 15.0% (95% CI = 8.0–23.0%, I2 = 75.23%, 8 studies). On the basis of this study, we conclude that although the prevalence of co-infection was low, patients with malaria appear at greater risk of bacteremia and death.

Prevalence and Transmission of Multi Drug Resistance Gene in Staphylococcus aureus

Abstract: Antibiotics are antimicrobial substances that are commonly used to treat humans, ani-mals, and fish, as well as to research susceptibility patterns in a variety of bacteria. With the rising number of diseases and the emergence of new infections, many drugs for humans, animals, fish, and plants are being developed. However, with the development of pharmaceuticals came the advent of a phenomenon known as drug resistance, which has alarmed scientists and researchers all around the world. The building of resistance in genes that code for specific drugs, plasmids, or transposons, the action of multidrug efflux pumps, changes in chromosomal genes, or the Staphylococci cassette chromosome can all produce it. Staphylococcus aureus, the most common Gram-positive bacteria, has a multidrug-resistant phenotype that reveals its pathogenicity. Staphylococcus sp. possesses a variety of transmissible genes that cause them to be resistant to treatments such as antibiotics. The discovery of antibiotics by Alexander Fleming has long been a boon in the fight against bacterial illnesses. Drug-resistant bacteria have emerged as a result of antibiotic overuse and suboptimal us-age, attracting the attention of scientists throughout the world. Therefore, as a first step in combat-ing drug-resistant bacteria, it is obvious that widespread efforts to curb antibiotic abuse are required. This review focuses on and brings to society the prevalence of different multidrug resistant genes in Staphylococcus aureus and their transmission.

Isolation and drug susceptibility pattern of uropathogens in Saudi diabetic and non-diabetic patients with urinary tract infection.

Urinary tract infection (UTI), contribute substantially to healthcare burden. Diabetes predispose to UTI with high glycosuria being fertile medium for bacterial growth. With changing bacterial drug resistance patterns; the problem needs to be studied periodically to ensure a rational therapy, minimize adverse effects, and cost. Therefore, it is of interest to compare the profile and susceptibility pattern of uropathogens isolated from diabetic and non-diabetic patients with UTI. Mid-stream urine samples of 1100 patients (diabetic and non-diabetic), presenting with UTI symptoms were aseptically collected and inoculated into CLED medium. Colony counts of 105cfu/ml or 104cfu/ml and >5 pus cells per high power microscopic field were regarded as significant bacteriuria. Colonies from CLED were sub-cultured onto sheep blood agar and MacConkey agar. Bacterial identification was performed on the basis of colony morphology, gram staining, and series of biochemical tests though Analytical Profile Index (API) test strips. Drug susceptibility was done by standard Kirby-Bauer disk diffusion. Data was analyzed by SPSS ver. 25.Clinically significant bacteriuria was 32.8% and 19.2% in diabetics and non-diabetics respectively. The frequency of male and female patients was 153 and 208 in diabetic group; and 69 and 142 respectively in non-diabetic group. Diabetics were twice at risk of UTI; [Odds ratio; 2.04 (CI: 1.68-2.48, p<0.05)]. .Escherichia coli and klebsiella were most common gram-negative, while Staphylococcus aureus and Coagulase-negative staphylococci (CoNS) were most common gram-positive bacteria in both the groups. Most effective antibiotics against gram-negative bacteria were carbapenems, amikacin, colistin, and piperacillin/tazobactam; while ampicillin/amoxicillin, fluoroquinolones and cephalexin were least effective. For gram-positives, vancomycin, linezolid and tigecycline were most effective. No significant difference in bacterial profile and susceptibility pattern was found between diabetics and non-diabetics. However, diabetics were twice at risk of UTI compared to non-diabetics.

Pathogen distribution and risk factors of bacterial and fungal infections after liver transplantation.

Liver transplant recipients have a high rate of postoperative infection, and identification of patients at high risk for bacterial and fungal infections will help prevent disease and improve long-term outcomes for them. This study aims to understand the composition, distribution, prognosis of bacterial and fungal infections within 2 months after liver transplantation and to analyze their risk factors. The data of pathogen composition, distribution, and prognosis of bacterial and fungal infections among liver transplant recipients in the Third Xiangya Hospital of Central South University from May 2020 to October 2021 were collected, and the risk factors for these infections were analyzed. A total of 106 episodes of bacterial or fungal infections occurred in 71.4% of liver transplant recipients (75/105). Gram-negative bacteria were the dominant pathogenic bacteria (49/106, 46.2%), followed by Gram-positive bacteria (31/106, 29.2%). The most common Gram-negative bacterium was Acinetobacter baumannii (13/106, 12.3%). The most common Gram-positive bacterium was Enterococcus faecium (20/106, 18.9%). The most common infections were pulmonary (38/105, 36.2%) and multiple site infections (30/105, 28.6%). Six (6/105, 5.7%) patients with infections died within 2 months after liver transplantation. Univariate analysis showed that the model for end-stage liver disease (MELD) score ≥25, antibiotic use within half a month before transplantation, infections within 2 months prior to transplantation, intraoperative red blood cell infusion≥8 U, indwelling urinary tract catheter ≥4 days after transplantation, and the dosage of basiliximab use ≥40 mg were associated with infections. Multivariate logistic regression analysis revealed that only infections within 2 months prior to transplantation (OR=5.172, 95% CI 1.905-14.039, P<0.01) was an independent risk factor for bacterial and fungal infections after liver transplantation. Postoperative bacterial and fungal infections were reduced in liver transplant recipients receiving basiliximab ≥40 mg (OR=0.197, 95% CI: 0.051-0.762, P<0.05). The incidence of bacterial and fungal infections is high in the early stage after liver transplantation, and the mortality after infection is significantly higher than that of non-infected patients. The most common infection is respiratory infection, and the dominant pathogens is Gram-negative bacteria. Patients infected within 2 months prior to liver transplantation are prone to bacterial and fungal infections. Standard use of basiliximab can reduce the incidence of infections after liver transplantation.

The association between bacteria and outcome and the influence of sampling method, in people with a diabetic foot infection

PurposeDifferent bacteria lead to divers diabetic foot infections (DFIs), and some bacteria probably lead to higher amputation and mortality risks. We assessed mortality and amputation risk in relation to bacterial profiles in people DFI and investigated the role of sampling method.MethodsWe included people (> 18 years) with DFI in this retrospective study (2011–2020) at a Dutch tertiary care hospital. We retrieved cultures according to best sampling method: (1) bone biopsy; (2) ulcer bed biopsy; and (3) swab. We aggregated data into a composite determinant, consisting of unrepeated bacteria of one episode of infection, clustered into 5 profiles: (1) Streptococcus and Staphylococcus aureus; (2) coagulase-negative Staphylococcus, Cutibacterium, Corynebacterium and Enterococcus; (3) gram-negative; (4) Anaerobic; and (5) less common gram-positive bacteria. We calculated Hazard Ratio’s (HR’s) using time-dependent-Cox regression for the analyses and investigated effect modification by sampling method.ResultsWe included 139 people, with 447 person-years follow-up and 459 episodes of infection. Sampling method modified the association between bacterial profiles and amputation for profile 2. HR’s (95% CI’s) for amputation for bacterial profiles 1–5: 0.7 (0.39–1.1); stratified analysis for profile 2: bone biopsy 0.84 (0.26–2.7), ulcer bed biopsy 0.89 (0.34–2.3), swab 5.9*(2.9–11.8); 1.3 (0.78–2.1); 1.6 (0.91–2.6); 1.6 (0.58–4.5). HR’s (95% CI’s) for mortality for bacterial profiles 1–5: 0.89 (0.49–1.6); 0.73 (0.38–1.4); 2.6*(1.4–4.8); 1.1(0.58–2.2); 0.80(0.19–3.3).ConclusionsIn people with DFI, there was no association between bacterial profiles in ulcer bed and bone biopsies and amputation. Only in swab cultures, low-pathogenic bacteria (profile 2), were associated with a higher amputation risk. Infection with gram-negative bacteria was associated with a higher mortality risk. This study underlined the possible negative outcome of DFI treatment based on swabs cultures.

Exploring the Role of Staphylococcus aureus in Inflammatory Diseases.

Staphylococcus aureus is a very common Gram-positive bacterium, and S. aureus infections play an extremely important role in a variety of diseases. This paper describes the types of virulence factors involved, the inflammatory cells activated, the process of host cell death, and the associated diseases caused by S. aureus. S. aureus can secrete a variety of enterotoxins and other toxins to trigger inflammatory responses and activate inflammatory cells, such as keratinocytes, helper T cells, innate lymphoid cells, macrophages, dendritic cells, mast cells, neutrophils, eosinophils, and basophils. Activated inflammatory cells can express various cytokines and induce an inflammatory response. S. aureus can also induce host cell death through pyroptosis, apoptosis, necroptosis, autophagy, etc. This article discusses S. aureus and MRSA (methicillin-resistant S. aureus) in atopic dermatitis, psoriasis, pulmonary cystic fibrosis, allergic asthma, food poisoning, sarcoidosis, multiple sclerosis, and osteomyelitis. Summarizing the pathogenic mechanism of Staphylococcus aureus provides a basis for the targeted treatment of Staphylococcus aureus infection.

Preparation and Characterization of Eco-Friendly Transparent Antibacterial Starch/Polyvinyl Alcohol Materials for Use as Wound-Dressing.

In this study, eco-friendly and transparent starch-based/polyvinyl alcohol/citric acid composite films are evaluated for their efficacy as wound dressing materials. The starch/polyvinyl alcohol (PVA) materials with added citric acid (0.46–1.83 wt%) and glycerol were made and handled based on the modified casting method. This new formulation decreases the amount of PVA used in the conventional preparation method. Citric acid ensures an appropriate antibacterial environment for wound-dressing materials. The mechanical, chemical, and surface morphological properties of such films were assessed and analyzed by tensile strength tests, UV–Vis spectrometry, swelling index, and scanning electron microscopy (SEM). Furthermore, the water vapor transmission (WVT) quantity was measured for an ideal wound-healing process to investigate an optimal moisture environment around the wound bed. Moreover, the pH level of the dressings was measured to examine the possibility of bacterial growth around these starch-based films. Additionally, the films’ in-vitro antibacterial activities were studied against the two most common Gram-positive and Gram-negative bacteria (Escherichia coli and Staphylococcus aureus). The new starch-based dressings demonstrated suitable degradation, antibacterial activity, fluid absorption, and adequate mechanical strength, representing wound-dressing materials’ vital features.

Microbiology and Outcome of Peritoneal Dialysis-Related Peritonitis in Elderly Patients: A Retrospective Study in China

ObjectiveThe number of elderly patients on peritoneal dialysis (PD) has rapidly increased in the past few decades. We sought to explore the microbiology and outcomes of peritonitis in elderly PD patients compared with younger PD patients.MethodsWe conducted a retrospective study to analyze the clinical characteristics, causative organism distribution, and outcome of all PD patients who developed peritonitis between September 1, 2014 and December 31, 2020, from Second Xiangya Hospital, Central South University, China. Patients who experienced peritonitis were separated into elderly and younger groups. The elderly was defined as ≥ 65 years old at the initiation of PD.ResultsAmong 1,200 patients, 64(33.9%) in elderly (n = 189) and 215 (21.3%) in younger (n = 1,011) developed at least one episode of peritonitis. A total of 394 episodes of peritonitis occurred in 279 patients. Of these, 88 episodes occurred in 64 elderly patients, and 306 episodes occurred in 215 younger patients. Gram-positive bacteria were the main causative organisms in elderly and younger patients (43.2% and 38.0%, respectively). Staphylococcus and Escherichia coli were the most common gram-positive and gram-negative bacteria, respectively. Fungal peritonitis in elderly patients was higher compared with younger patients (χ2 = 6.55, P = 0.01). Moreover, Acinetobacter baumannii (χ 2=9.25, P = 0.002) and polymicrobial peritonitis (χ 2 = 6.41, P = 0.01) in elderly patients were also significantly higher than that in younger patients. Additionally, elderly PD patients had higher peritonitis-related mortality than younger patients (χ 2 = 12.521, P = 0.000), though there was no significant difference in catheter removal between the two groups. Kaplan-Meier analysis showed that cumulative survival was significantly lower in elderly patients than younger patients (log rank = 7.867, p = 0.005), but similar technical survival in both groups (log rank = 0.036, p = 0.849).ConclusionsThis retrospective study demonstrated that elderly PD patients were more likely to develop Acinetobacter baumannii, fungal and polymicrobial peritonitis than younger PD patients. In addition, peritonitis-related mortality was significantly higher in elderly patients, whereas peritonitis-related catheter removal was comparable between elderly and younger PD patients. Understanding microbiology and outcome in elderly patients will help to reduce the incidence of PD-associated peritonitis and improve the quality of life.

Antibacterial Activity and Phytochemical Screening of Erythrina fusca Lour. Leaf Extract (Fabaceae)

Erythrina fusca Lour. (family Fabaceae) is a flowering tree that is locally known as ‘chengkering’. The plant is traditionally used in treatment of some symptoms related to bacterial infections such as wound infections, inflammations, and skin itching. This work reports for the first time in vitro antibacterial screening of the E. fusca Lour. methanolic leaf extract against some common Gram-negative and Gram-positive bacteria such as Klebsiella pneumonia, Proteus vulgaris, Pseudomonas aeruginosa, Bacillus cereus, Bacillus subtilis, and Staphylococcus aureus. The in vitro antibacterial assay was carried out using agar diffusion method with the extract concentration of 3 mg/well and vancomycin 30 µg/well as the positive control. It was found that the extract exhibits antibacterial effects in range of 10.5 – 14 mm of zone of inhibition (ZOI) against all tested bacteria except for K. pneumoniae. P. aeruginosa showing ZOI of 14 mm was the most sensitive bacterium while P. vulgaris (ZOI of 10.5 mm) was the least sensitive strain to the extract. Based on the preliminary phytochemical screening of using standard qualitative phytochemical tests, this species contains significant amount of alkaloids, flavonoids, terpenoids, and tannins, which might contribute to the antibacterial activity of the extract. Both antibacterial potential and presence of various phytochemicals in the extract could support the traditional uses of E. fusca , and the obtained results would serve as a basis for further exploration of antibacterial properties of the plant’s leaves.

Establishing a MALDI-TOF-TOF-MS method for rapid identification of three common Gram-positive bacteria (Bacillus cereus, Listeria monocytogenes, and Micrococcus luteus) associated with foodborne diseases

We aimed to establish a method for the rapid identification of three common Gram-positive bacteria (Bacillus cereus, Listeria monocytogenes, and Micrococcus luteus) associated with foodborne diseases. MALDI-TOF-MS was used to determine the effects of sample pretreatment, culture medium, and culture time on the identification results. Then, MALDI-TOF-TOF-MS was used to establish an optimized method and further explore the effects of culture time on secondary proteins. Among the three sample pretreatment methods, formic acid extraction outperformed direct transfer and extended direct transfer, resulting in more protein peaks and higher peak intensity in B. cereus culture samples. However, with different culture times (1–7 d), ion peaks of all bacterial proteins were relatively stable according to MALDI-TOF-TOF-MS data. The protein peaks of B. cereus (1430 m/z), L. monocytogenes (2100 m/z), and M. luteus (2140 m/z) were split into small ion peaks at 1162, 1465, and 1625 m/z, respectively. After 7 d of culture, the secondary spectra, peak intensities, and peak values of formic acid-treated samples were relatively stable, indicating that secondary protein peaks were less affected by culture time. It provides a new approach for the routine identification and market supervision of food safety in China.

Relationship between high bile juice amylase levels and chronic bacterial infections in patients with gallbladder cancer.

PurposePancreatic enzyme reflux into the biliary tract is associated with chronic inflammation and increased cellular proliferation in the biliary epithelium, leading to biliary carcinoma. We evaluated the relationship between high bile juice amylase levels and biliary microflora in patients with malignant gallbladder lesions.MethodsIn this retrospective study, 25 gallbladder specimens were obtained from patients with gallbladder cancer to evaluate amylase levels and perform bacterial culture. The samples were divided into high and low amylase groups and culture-positive and negative groups for analysis. Bile juice amylase 3 times higher than the normal serum amylase level (36–128 IU/L) was considered high.ResultsThe number of positive cultures was higher in the high amylase group than in the low amylase group, but the difference was insignificant. There were no differences in other clinicopathological factors. Sixteen patients showed positive culture results; Escherichia coli and Klebsiella spp. were the most common gram-negative bacteria, whereas Enterococcus and Streptococcus spp. were the most common gram-positive bacteria. Age and bile juice amylase levels were significantly higher in the culture-positive group than in the culture-negative group. The incidence of bacterial resistance to cephalosporins was 6.25%–35.29%, and this incidence was particularly high for lower-generation cephalosporins.ConclusionBacteria in gallbladder were identified more frequently when the amylase level was high. High amylase levels in the gallbladder can be associated with caused chronic bacterial infections with occult pancreaticobiliary reflux, potentially triggering gallbladder cancer.

Antimicrobial resistance in Libya: A systematic literature review of two decades

Background: In low- and middle-income countries, antimicrobial resistance (AMR) imposes a significant burden on patients and health-care systems. Due to a lack of data, the overall impact of AMR in Libya is not well known or documented. As a result, this study presents the results of a review of available data on AMR in Libya over the past 20 years (from 2002 to 2021) to aid understanding of the current AMR situation in this portion of the continent. Methods: Articles related to the topic were researched using databases and search engines such as PubMed, Google Scholar, and ResearchGate websites. These articles were selected based on predetermined inclusion and exclusion criteria. The total number of tested isolates for each of the reported Bacterial spp. was used to calculate antibiotic resistance to a specific bacterium. Results: Studies published in the past 20 years, representing reports of 18,160 AMR tests, showed that Urinary Tract Infection (UTI) was the most reported clinical diagnosis in Libya (61.3%). Out of 43 articles, Staphylococcus aureus was the most common Gram-positive bacteria documented in (31, 61.3%) studies, and was most common in 59.78% of skin infections. Whereas, Pseudomonas spps., were the most common Gram-negative bacteria presented in (23, 53.48%) studies, and were commonly isolated in respiratory infection (9.39%). Among Gram-negative bacteria, Pseudomonas spp. reported a high resistance percentage for penicillin beta-lactam antibiotic, i.e., piperacillin (10.4%) and to the first-generation cephalosporins antibiotics, i.e., cefazolin (7.7%). However, they are susceptible to metronidazole, vancomycin, and colistin. Gram-positive bacteria, S. aureus shows high resistance to oxacillin, followed by gentamycin and cefoxitin (8.5%, 8.3%, and 8.3%, respectively). Effective antibiotics against S. aureus were azithromycin, clarithromycin, and metronidazole, whose susceptibility was 99.9% each, while 1% of S. aureus were vancomycin-resistant S. aureus. Conclusion: This study gives a comprehensive analysis of the state of AMR in Libya with respect to the most regularly prescribed antibiotics. The findings of the research show the alarmingly persistent occurrences of AMR in Libya, as well as the critical need to establish national action, plans to combat AMR and improve surveillance programs.

Recombinant expression and coexpression of oyster defensin and proline-rich peptide in Komagataella phaffii.

Proline-rich peptide (CgPrp) and defensin (CgDef), oyster (Crassostrea gigas)-originated antimicrobial peptides (AMPs), were produced by the recombinant technique in Komagataella phaffii GS115 cells. For this purpose, the nucleotide sequences encoding the CgPrp and CgDef peptides were synthesized by the recursive PCR technique, and ligated in pPICZaA expression vector. Additionally, the expression cassettes of pPICZαA-CgDef and pPICZαA-CgPrp were combined using in vitro multimer ligation strategy to construct the coexpression vector pPICZaA-CgPrp-CgDef. The expression and coexpression vectors transformed into K. phaffii GS115 cells by electroporation. At the end of the 0.5% methanol-induced expression stage for 96h, the recombinant peptides were purified from the culture medium. The concentrations of purified peptides were changed between 1.05 and 1.21mg/L. The recombinant peptides successfully inhibited the growth of tested Gram-positive bacterial strains belonging to Staphylococcus aureus, methicillin-resistant S. aureus (MRSA), Listeria monocytogenes, and Bacillus cereus. The minimum inhibitory concentrations (MIC) of recombinant CgPrp, CgDef, and CgPrp-CgDef peptides against tested bacteria were in the range of 12.50-25.00, 18.75-75.00, and 5.80-11.60pg/μl, respectively. The results of the study proved that the recombinant CgPrp, CgDef, and CgPrp-CgDef peptides expressed in K. phaffii might have good potential for the inhibition of common Gram-positive pathogenic bacteria, including drug-resistant MRSA.

The value of procalcitonin for predicting urosepsis after mini-percutaneous nephrolithotomy or flexible ureteroscopy based on different organisms.

To assess the value of procalcitonin (PCT) as an early biomarker for predicting urosepsis caused by Gram-negative (GN) bacteria, Gram-positive (GP) bacteria and fungi following mini-percutaneous nephrolithotomy (mPCNL) and flexible ureteroscopy (FURS). A total number of 356 patients with positive preoperative UC (urine cultures) who underwent mPCNL and FURS between June 2017 and January 2021 were retrospectively analyzed. Univariable analysis and multivariable logistic regression analysis were conducted to compare the predictors for urosepsis caused by different organisms. Furthermore, the nomogram was established as a predicted model for urosepsis. Among 356 positive UC, 265 (74.4%) were positive for GN bacteria, 77 (21.4%) for GP bacteria and 14 (3.9%) for fungal pathogens. Escherichia coli (48.9%) were the predominant pathogens and Enterococcus (54/77) were the most common GP bacteria. Multivariate logistic regression analysis showed that positive nitrite (OR 3.31, 95% CI 1.20-9.14; P = 0.021), operative time > 90min (OR 3.10, 95% CI 1.10-8.75, P = 0.033) and postoperative PCT > 0.1ng/mL (OR 56.18, 95% CI 15.20-207.64, P < 0.001) were associated with postoperative urosepsis originated in GN infections, while urosepsis caused by GP bacteria and fungi was not associated with PCT > 0.1ng/mL (P = 0.198), only stone burden > 800mm2 (OR 3.69, 95% CI 1.01-13.53, P = 0.049) was an independent risk factor. For patients with positive preoperative UC, postoperative PCT > 0.1ng/mL was an independent risk factor of post-PCNL and post-FURS urosepsis caused by GN bacteria rather than GP bacteria and fungi.

Activity of the lyases LysSSE1 and HolSSE1 against common pathogenic bacteria and their antimicrobial efficacy in biofilms

Bacillary dysentery is a common foodborne disease with an exaggerated mortality rate because of Shigella infection. With the increasing severity of Shigella infection, lyase has been considered as the most promising alternative to antimicrobial agents, owing to the emergence of resistant bacteria and the difficulty in disrupting and eliminating bacterial biofilms. In this study, we cloned and characterised HolSSE1 and LysSSE1, holin, and lysozyme from the S. dysenteriae phage SSE1 with extended bacterial host range against common gram-negative and gram-positive bacteria. In addition, the efficacy of HolSSE1 and LysSSE1 in removing bacterial biofilms was observed on polystyrene surfaces. Moreover, synergistic bacteriostasis was observed when they were used together. Alignment and structural model analysis showed that both HolSSE1 and LysSSE1 are T4 phage proteins that have not yet been identified. Therefore, HolSSE1 and LysSSE1 can be promising biocontrol agents for the prevention and treatment of various pathogenic infections.

Selective inactivation of Gram-positive bacteria in vitro and in vivo through metabolic labelling

Bacterial infections are grave threats to human health, particularly those caused by the most common Gram-positive bacteria. The massive administration of broad-spectrum antibiotics to treat various bacterial infections has led to the evolution and spread of drug resistance. As a universal antimicrobial technique unapt to induce drug resistance, photothermal therapy (PTT) is attracting extensive attention in recent years. However, its unspecific killing capability and side effects towards adjacent mammalian cells severely impede the practical applications. Herein, we proposed a metabolic engineering strategy to selectively inactivate Gram-positive bacteria by PTT. A bioorthogonal photothermal agent was prepared by the conjugation of IR-780 iodide and dibenzo-cyclooctyne (IR780-DBCO). Upon pre-metabolizing with 3-azido-D-alanine, Gram-positive bacteria rather than Gram-negative ones, such as Staphylococcus aureus and vancomycin-resistant Enterococcus faecalis (VRE), could be specifically tied up by the explosive IR780-DBCO via copper-free click chemistry. Thereafter, they spontaneously detonated under 15 min near-infrared light irradiation and inactivated nearly 100% Gram-positive bacteria in vitro. Moreover, superbug VRE-induced infection was significantly inhibited by this approach in a mouse skin wound model. This metabolic labelling-based photothermal ablation strategy specific to Gram-positive microbes would stimulate the development of precise anti-bacterial candidates for preclinical applications.

Analysis of antibiotics administration in diabetic ulcer patients at Panembahan Senopati regional hospital Bantul

Background: This study provides an overview of diabetic ulcer infection, antibiotic susceptibility patterns, the most common types of antibiotics, factors influence in antibiotics administrations, and verifying the guideline used of antibiotics.Methods: The research used descriptive analysis combined with interviews. The study was starting from February-March 2021. Eighty-six diabetic ulcer patients were selected considering the inclusion and exclusion criteria. We interviewed seven doctors.Results: 71 bacterias were found with a gram-negative bacteria count of 80.3%- higher than gram-positive bacteria (19.7%). The most common gram-negative bacteria found are Escherichia coli (12.7%) and show the most heightened sensitivity with imipenem (80.7%), while cefuroxime and trimethoprim-sulfamethoxazole show the highest resistance (64.9%). The most common gram-positive bacteria found are Staphylococcus aureus (14.1%), and vancomycin shows the most heightened sensitivity (100%), while penicillin shows the highest resistance (71.4%). The most common single antibiotic administration was ceftriaxone, as well as a combination of two antibiotics, namely ceftriaxone and metronidazole.Conclusions: Escherichia coli was the most gram-negative bacteria, which has the highest sensitivity with imipenem, while Staphylococcus aureus was the most gram-positive bacteria, which has the most heightened sensitivity with vancomycin. The most common single antibiotic administration was ceftriaxone, as well as a combination of two antibiotics, ceftriaxone and metronidazole. Factors that influence antibiotics administration are patient condition, susceptibility testing, training, and advice from colleagues. Every doctor uses different guidelines for diabetic foot ulcer.

English

BACKGROUND Dacryocystitis is one of the most frequent diseases of the efferent lacrimal system. It is the infection or inflammation of the lacrimal sac. This is usually because of nasolacrimal duct obstruction. Acute dacryocystitis can cause severe morbidity and rarely mortality in patients. This study wanted to identify the aerobic bacterial aetiology, and demonstrate the antibiogram of bacterial isolates of acute dacryocystitis. METHODS A retrospective record-based study was conducted in Rural Tertiary Healthcare Centre. Clinical Data of 89 patients was collected from medical records of 2014 to 2018 documents. Data of bacterial isolates and their antibiogram were retrieved from records in the Department of Microbiology. RESULTS The most common aerobic Gram-positive bacteria were Staphylococcus aureus (29.8 %) and Coagulase Negative staphylococcus (23.3 %). The most common Gramnegative bacteria were pseudomonas spp. (19.4 %) and klebsiella spp. (12.9 %). CONCLUSIONS The knowledge of bacterial profile in different geographic region, different age group will help to develop and implement treatment protocol. KEY WORDS Acute Dacryocystitis, Bacterial Profile, Antibiogram

Fibrin(ogen)-Pathogen Interactions Support Antimicrobial Host Defense Following Staphylococcus Aureus Peritonitis Infection

Staphylococcus aureus is a common gram-positive bacterium that is a frequent cause of community and hospital-acquired infections. The emergence of antibiotic resistant S. aureus hashighlighted a renewed need to better understand host-pathogen interactions for defining novel treatment strategies. The clotting factor fibrinogen is a target of several S. aureus virulence factors. Clumping factor A (ClfA) is a well characterized fibrin(ogen) binding protein known to mediate bacterial adhesion and clumping in blood plasma and has been shown to play an important role in several types of S aureus infections. Studies using Fib-/- (fibrinogen deficient) and FibAEK (mice expressing fibrinogen unable to form a fibrin polymer) indicated that fibrinogen and subsequent fibrin polymer formation are critical for clearance of USA300 S. aureus following peritonitis. Here, we tested the hypothesis that ClfA-fibrin(ogen)interactions are a key mechanistic feature of host antimicrobial function following S. aureus peritonitis. Analyses were performed with FibγΔ5 mutant mice, which express a mutant form of fibrinogen lacking the final 5 amino acids of the g chain encoding the bacterial ClfA binding motif. In vitro studies confirmed that fibrinogenWT supported robust bacterial adhesion and clumping whereas a complete absence of adhesion and clumping was observed using fibrinogenγΔ5. Infection studies of WT and FibγΔ5 mice revealed that ClfA-mediated, fibrin(ogen)- S. aureus interactions are an important determinant of host antimicrobial function in the context of peritonitis. Taken together, these data indicate that direct, ClfA-mediated binding of bacteria to fibrin(ogen) is a critical mechanistic component of host antimicrobial function following S. aureus peritonitis. DisclosuresNo relevant conflicts of interest to declare.