Gram-positive Bacterial Growth Research Articles

Clinical outcomes in peritoneal dialysis with refractory peritonitis: significance of the day 5 cell count.

Peritoneal dialysis-associated peritonitis is a common and severe complication of peritoneal dialysis, associated with high morbidity and mortality. However, there's a lack of research on refractory peritonitis, which is difficult to manage and has a poor prognosis. Our study aimed to investigate factors affecting clinical outcomes in peritoneal dialysis patients with refractory peritonitis over a 12-year period at a medical faculty hospital in Turkey. We conducted a retrospective study at a single center from January 2009 to December 2020, involving 135 patients with 236 episodes of refractory peritonitis. The average age of the patient cohort was 53.0 ± 15.9years, and 72 (53.4%) of the patients were male. The leading identified causes of end-stage kidney disease were glomerulonephritis, hypertensive glomerulosclerosis, and diabetic nephropathy. Data on microbiological etiology, dialysate white blood cell counts, and patient demographics were analyzed to identify catheter removal risk factors. Statistical significance was set at p ≤ 0.05. Comparative analysis between patients with and without catheter loss revealed no significant differences in gender, age, presence of diabetes, prior hemodialysis, or duration of peritoneal dialysis. However, multivariate logistic regression analysis showed thata dialysate white blood cell count exceeding 1000/mm3 on day 5and hospitalization had a positive associationwith catheter loss, while the presence of gram-positive bacterial growth had an inverse correlation. Our study shows that fifth-day dialysate white blood cell count predicts refractory peritonitis outcomes. Future research should focus on developing tools to manage catheter removal proactively and enhance patient prognosis.

Silver sulphide nanoparticles (Ag2SNPs) synthesized using Phyllanthus emblica fruit extract for enhanced antibacterial and antioxidant properties.

In this study, silver sulfide nanoparticles (Ag2SNP's) were successfully produced by using fruit extracts of Phyllanthus emblica. UV-vis, FTIR, XRD with SEM and EDX techniques were used for the synthesis process and for characterization of the resulting nanostructures. According to the findings, the fabricated nanostructure had a monoclinic crystal structure, measuring 44 nm in grain size, and its strain was 1.82 × 10-3. As revealed by SEM analysis, the synthesized nanostructure consists of irregular spherical and triangular shapes. The presence of silver (Ag) and sulfur (S) was also confirmed through EDX spectra. Furthermore, Ag2S nanoparticles were tested for their ability to effectively inhibit gram-positive and gram-negative bacterial growth. As a result of this study, it was clearly demonstrated that Ag2S nanoparticles possess powerful antibacterial properties, particularly when it came to inhibiting Escherichia coli growth. Ag2S nanoparticles had high total H2O2 and flavonoid concentrations and the greatest overall antioxidant activity, according to the evaluation of antioxidant activity of the samples. The results obtained from the P. emblica fruit extract were followed by those obtained from Ag2S nanoparticles were reported in detail. RESEARCH HIGHLIGHTS: Innovative Ag2SNP synthesis using Phyllanthus emblica fruit extract. SEM with EDX revealed a monoclinic crystal structure with a grain size of 44 nm and a strain of 1.82 × 10-3. Many of these applications are demonstrated by the potential of Ag2SNPs to treat and combat bacteria, particularly Escherichia coli. A peak at 653 cm-1 indicates the presence of primary sulfide aliphatic C-S extension vibrations. The abundant H2O2 and NO2 found in P. emblica nanocomposites make them potent antioxidants.

Mesoporous Mg–Al–Ti composite oxide incorporated mixed matrix ultrafiltration membrane with superior multi-heavy metal removal capacity, anti-fouling & anti-microbial property

Mesoporous Mg–Al–Ti ternary composite oxide nano-adsorbents have demonstrated an exceptional performance to remove multiple heavy metals (As, Pb, Cd, Cr). Incorporation of these nanoparticles (NPs) in polysulfone membrane created a multifunctional mixed matrix membrane (MMM) with heavy metal adsorption capacity (both cationic and anionic species), enhanced hydrophilicity, anti-fouling property, and anti-microbial activity. The best heavy metal removal performance was shown by the membrane incorporated with 0.8 wt% NPs. Hydrophilicity improvement was studied through the decrease in water contact angle from 71° to 57° and surface probing using atomic force microscopy (AFM). With a maximum As(III) adsorption capacity of 256.6 mg/g, the membrane had a breakthrough volume of 25L and could provide safe drinking water for 19 h from a real Arsenic (As) contaminated groundwater sample with a flux of 48 l/m2-h. Beyond that, >90 % removal of Cd, Pb & Cr was also observed with maximum adsorption capacity of 652.9 mg/g, 332.5 mg/g, and 89.4 mg/g respectively. 92.5 % flux recovery after filtering a 1000 ppm bovine serum albumin showed the anti-fouling property. Successful inhibition of both gram-positive and gram-negative bacterial growth, and >99.99 % removal of colony forming units (CFU/ml) in the filtration process confirmed the anti-microbial resistance. With its multifunctionality, these membranes hold great potential for practical water treatment applications.

Inhibition of multiple staphylococcal growth states by a small molecule that disrupts membrane fluidity and voltage.

New molecular approaches to disrupting bacterial infections are needed. The bacterial cell membrane is an essential structure with diverse potential lipid and protein targets for antimicrobials. While rapid lysis of the bacterial cell membrane kills bacteria, lytic compounds are generally toxic to whole animals. In contrast, compounds that subtly damage the bacterial cell membrane could disable a microbe, facilitating pathogen clearance by the immune system with limited compound toxicity. A previously described small molecule, D66, terminates Salmonella enterica serotype Typhimurium (S. Typhimurium) infection of macrophages and reduces tissue colonization in mice. The compound dissipates bacterial inner membrane voltage without rapid cell lysis under broth conditions that permeabilize the outer membrane or disable efflux pumps. In standard media, the cell envelope protects Gram-negative bacteria from D66. We evaluated the activity of D66 in Gram-positive bacteria because their distinct envelope structure, specifically the absence of an outer membrane, could facilitate mechanism of action studies. We observed that D66 inhibited Gram-positive bacterial cell growth, rapidly increased Staphylococcus aureus membrane fluidity, and disrupted membrane voltage while barrier function remained intact. The compound also prevented planktonic staphylococcus from forming biofilms and a disturbed three-dimensional structure in 1-day-old biofilms. D66 furthermore reduced the survival of staphylococcal persister cells and of intracellular S. aureus. These data indicate that staphylococcal cells in multiple growth states germane to infection are susceptible to changes in lipid packing and membrane conductivity. Thus, agents that subtly damage bacterial cell membranes could have utility in preventing or treating disease.IMPORTANCEAn underutilized potential antibacterial target is the cell membrane, which supports or associates with approximately half of bacterial proteins and has a phospholipid makeup distinct from mammalian cell membranes. Previously, an experimental small molecule, D66, was shown to subtly damage Gram-negative bacterial cell membranes and to disrupt infection of mammalian cells. Here, we show that D66 increases the fluidity of Gram-positive bacterial cell membranes, dissipates membrane voltage, and inhibits the human pathogen Staphylococcus aureus in several infection-relevant growth states. Thus, compounds that cause membrane damage without lysing cells could be useful for mitigating infections caused by S. aureus.

Development of novel carboxymethyl cellulose/gelatin-based edible films with pomegranate peel extract as antibacterial/antioxidant agents for beef preservation

Novel antioxidant and antibacterial composite films were fabricated by incorporating pomegranate peel extract (PPE) into gelatin and carboxymethyl cellulose matrices. Increasing PPE concentration significantly (p < 0.05) altered physical properties and improved UV (decrease in light transmission 87.30 % to 9.89 % at 400 nm) and water resistance, while FTIR and molecular docking results revealed hydrogen bonding between PPE and film matrix. PPE incorporation enhanced antioxidant activity up to 84.15 ± 0.12 % and also restricted gram-positive and gram-negative bacterial growth by 72.4 % and 65.9 % respectively after 24 h, measured by antimicrobial absorption assays. For beef packaging applications at refrigeration temperatures, PPE films were most effective at extending shelf-life up to 3 days, as evidenced by reduced total viable counts, total volatile basic nitrogen, weight loss, and pH changes compared to control films. Therefore, these antioxidant and antibacterial films have potential applications in food packaging to protect against mechanical stress, light exposure, microbial spoilage, and oxidative free radicals.

Multifunctional Spirogyra-hyalina-Mediated Barium Oxide Nanoparticles (BaONPs): Synthesis and Applications.

This research aims to biosynthesize Barium oxide nanoparticles (BaONPs) for biomedical applications, using Spirogyra hyalina as a stabilizing and reducing agent. UV-visible spectroscopy, Fourier transform infrared spectroscopy (FTIR), energy-dispersive X-ray, X-ray diffraction (XRD), and scanning electron microscopy (SEM) were used to physiochemically characterize the barium oxide nanoparticles, while antibacterial, minimum inhibitory concentration, antifungal, free radicle scavenging, and anti-inflammatory assay were performed to assess the therapeutic potential of the synthesized BaONPs. Fourier transform infrared spectroscopy revealed bands at 615 and 692 cm-1 that corresponded to the formation of BaONPs. Scanning electron microscopy revealed the spherical and flower-shaped morphology of BaONPs having an average diameter of 64.01 ± 2.0 nm. Both Gram-positive and Gram-negative bacterial growth was halted by the barium nanoparticles, demonstrating their efficacy up to 19.12 ± 0.31 mm against E. coli, 18.83 ± 0.44 mm against Klebsiella pneumoniae, 17.31 ± 0.59 mm against P. aeruginosa, 16.56 ± 0.37 mm against S. aureus, and 15.75 ± 0.38 mm against S. epidermidis, respectively. The minimum inhibitory concentration was 9.0, 6.3, 5.5, 4.5, and 2.0 µg/mL for S. aureus, Klebsiella pneumoniae, S. epidermidis, P. aeruginosa, and E. coli, respectively. BaONPs were not that effective against fungal strains such as Rhizoctonia solani, Fusarium solani, and Fusarium proliferatum. The BaONPs exhibited potent anti-inflammatory and antioxidant activity through inhibiting cyclooxygenases type 1 (43.12 ± 1.21%) and 2 (41.23 ± 1.56%), and DPPH free radicles up to 43.52 ± 0.29% at 400 µg/mL. In conclusion, the biomolecules derived from Spirogyra hyalina have demonstrated remarkable ability to generate stable nanoparticles, offering promising prospects for their utilization as therapeutic agents and coating materials in various biomedical applications.

Lowering the Incidence of Endophthalmitis Following Intravitreal Anti-VEGF Injection: An Analysis of Aseptic Protocol Adjustment.

The impact of anti-sepsis-anesthesia sequence in intravitreal injection (IVI)-associated endophthalmitis is unknown. We compared outcomes of patients who had 10% topical povidone-iodine before or after 2% topical lidocaine gel during IVIs. A retrospective study of IVIs in nine clinical sites was undertaken. Group 1 had lidocaine gel applied first. This protocol was changed on March 1, 2020, with Group 2 having povidone-iodine applied first. Visual and micro-biological outcomes were compared. Among 72 cases (0.07%) from 102,908 IVIs, Group 1 had 59 cases from 65,307 IVI (0.09%) and Group 2 had 13 cases from 37,601 IVI (0.03%; P = 0.001). There was no significant difference in the best-corrected visual acuity between groups. Highly virulent bacteria were predominantly isolated in Group 1, but proportions of gram-positive bacterial growth were similar. Application of povidone-iodine before lidocaine gel, compared to after, significantly decreased rate of IVI endophthalmitis, with no significant changes in visual and microbiological outcomes. [Ophthalmic Surg Lasers Imaging Retina 2023;54:520-525.].

Sortase A Inhibitor Protein Nanoparticle Formulations Demonstrate Antibacterial Synergy When Combined with Antimicrobial Peptides.

Sortase A (SrtA) is an enzyme which attaches proteins, including virulence factors, to bacterial cell walls. It is a potential target for developing anti-virulence agents against pathogenic and antimicrobial resistant bacteria. This study aimed to engineer 𝛽-lactoglobulin protein nanoparticles (PNPs) for encapsulating safe and inexpensive natural SrtA inhibitors (SrtAIs; trans-chalcone (TC), curcumin (CUR), quercetin (QC), and berberine (BR)) to improve their poor aqueous dispersibility, to screen for synergy with antimicrobial peptides (AMPs), and to reduce the cost, dose, and toxicity of AMPs. Minimum inhibitory concentration (MIC), checkerboard synergy, and cell viability assays were performed for SrtAI PNPs against Gram-positive (methicillin-sensitive and -resistant S. aureus) and Gram-negative (E. coli, P. aeruginosa) bacteria alone and combined with leading AMPs (pexiganan, indolicidin, and a mastoparan derivative). Each SrtAI PNP inhibited Gram-positive (MIC: 62.5-125 µg/mL) and Gram-negative (MIC: 31.3-500 µg/mL) bacterial growth. TC PNPs with pexiganan demonstrated synergy against each bacteria, while BR PNPs with pexiganan or indolicidin provided synergy towards S. aureus. Each SrtAI PNP inhibited SrtA (IC50: 25.0-81.8 µg/mL), and did not affect HEK-293 cell viability at their MIC or optimal synergistic concentrations with AMPs. Overall, this study provides a safe nanoplatform for enhancing antimicrobial synergy to develop treatments for superbug infections.

Synthesis of a novel visible-light active Gd2O3/GdVO4/V2O5 photocatalyst for rapid purification of industrial wastewater containing organic dyes and bacteria

In the past decades, population growth and industrial development have posed a significant threat to the aquatic environment and water pollution, considerably influencing our living standards. In the present study, novel visible light-responsive nano photocatalysts Gd2O3/GdVO4/V2O5 were synthesized by mechanical alloying and sintered at different elevated temperatures. All the structural and microstructural parameters of the mechanosynthesized C12.6N0.6VO3 phase have been modified from the reported values. XRD, TEM, SEM, XPS, and FTIR are employed to characterize the as-obtained nanocomposites with elemental mapping. The surface or grain boundary defects, bandgap, and Urbach energy of the nanocomposites are revealed by diffused reflectance spectroscopy (DRS) and BET analysis. The photodegradation and quantum efficiency of the samples are investigated by analyzing UV–Vis spectra, using Rhodamine B (RhB), Congo Red (CR), and Methylene Blue (MB) as model organic dye pollutants. Experimental results reflect that the 5 h milled and sintered sample shows better photocatalytic degradation efficiency of almost 100% within 150 min - nearly twice that of pure precursor materials. Scavenger tests ensure the oxidative radical species involved in the photodegradation mechanism. The antibacterial study reveals that the Gd2O3/GdVO4/V2O5 nanocomposite efficiently prohibits gram-positive bacterial growth in the wastewater. These Gd2O3 /GdVO4 /V2O5 nanocomposites may be utilized as an efficient tool for wastewater treatment in industrial areas and prohibiting bacterial growth in wastewater.

Antibacterial and Antifungal Properties of a Novel Antimicrobial Peptide GK-19 and Its Application in Skin and Soft Tissue Infections Induced by MRSA or Candida albicans.

The increasing resistance of human pathogens promotes the development of novel antimicrobial agents. Due to the physical bactericidal mechanism of membrane disruption, antimicrobial peptides are considered as potential therapeutic candidates without inducing microbial resistance. Scorpion venom-derived peptide, Androctonus amoreuxi Antimicrobial Peptide 1 (AamAP1), has been proved to have broad-spectrum antimicrobial properties. However, AamAP1 can induce hemolysis and shows strong toxicity against mammalian cells. Herein, the antimicrobial activity and mechanism of a novel synthetic antimicrobial peptide, GK-19, derived from AamAP1 and its derivatives, was evaluated. Five bacteria and three fungi were used to evaluate the antimicrobial effects of GK-19 in vitro. Scalded mice models combined with skin and soft tissue infections (SSTIs) were used to evaluate its applicability. The results indicated that GK-19 could not only inhibit Gram-positive and Gram-negative bacterial growth, but also kill fungi by disrupting the microbial cell membrane. Meanwhile, GK-19 showed negligible toxicity to mammalian cells, low hemolytic activity and high stability in plasma. Furthermore, in scalded mice models combined with SSTIs induced by either Methicillin-Resistant Staphylococcus aureus (MRSA) or Candida albicans, GK-19 showed significant antimicrobial and healing effects. Overall, it was demonstrated that GK-19 might be a promising drug candidate in the battle against drug-resistant bacterial and fungal infections.

Successful treatment of type ii diabetes mellitus with infected diabetic foot ulcer caused by ESBL producing Klebsiella pneumonia with cefepime plus sulbactam (Supime): A case report

Diabetic patients are at significant risk of developing neuropathy, leading to a diabetic foot injury. Complications of diabetic foot injury may lead to gangrene and non-traumatic lower extremity amputations. Diabetic patients with diabetic foot ulcers are more prone to bacterial infections and are associated with high chances of amputation. The diabetic patient flora provides an ideal environment for Gram-positive and Gram-negative bacterial growth, leading to increased morbidity and mortality. The antimicrobial-resistant Gram-negative bacterial infections in diabetic patients have a higher probability of amputation. Here we discuss a case of a 70-year male diabetic patient successfully treated with Supime (cefepime plus sulbactam) who had undergone an amputation of the right great toe and infected left foot ulcer due to ESBL producing K. Pneumonia.

Antibacterial activity of functional bioactive peptides derived from fish protein hydrolysate

By-product removal in fish processing is estimated to be between 25 and 70% due to improper fish production handling and significant problems in the fish industry today. Therefore, one of the ways to manage the raw material of by-product is through protein hydrolysis. However, one of the most effective methods for managing this raw material, which includes skin, bones, heads, and viscera, is to convert their protein into peptides via hydrolysis methods, resulting in fish protein hydrolysate (FPH). FPH has been shown to have bioactive properties such as antibacterial, antihypertensive, antioxidative, anticancer, and anticoagulant properties. Bioactivity could be fully utilised in the future in both the nutraceutical and food industries. Numerous studies have been published on the acceptability of FPH in obtaining bioactive properties from various fish, particularly antibacterial activity. For example, the antibacterial peptide was identified as FPIGMGHGSRPA, consisting of 12 amino acids. Its antibacterial activity was tested against B. subtilis using 800 g/mL ampicillin. The inhibition zone increased with peptide concentration. This review discusses functional bioactive peptides derived from fish protein hydrolysate that can be used as antibacterial agents by inhibit Gram-positive and Gram-negative bacterial growth. It also covers fish species, parts, and hydrolysis methods to maximise yields.

Biosynthesis of Silver Nanoparticles by Punica Granatum Peel Extract and their Biological Activity on different Pathogenic Bacteria

The present study was included the assessment of the antimicrobial activity of AgNPs synthesized by Punica granatum peel extract against pathogenic bacteria by testing warm aqueous P. granatum peel extract and silver nanoparticles. Punica granatum indicated potency for AgNP extracellular nanobiosynthesis after addition of silver nitrate (AgNO3) 4mM to the extract supernatant, in both concentrations (100mg and 50mg). The biogenic AgNPs showed potency to inhibit both gram-negative and gram-positive bacterial growth. Zons of inhibition in (mm) was lesser in gram-positive than gram-negative bacteria. The resulted phytogenic AgNPs gave higher biological activity than warm aqueous Punica granatum peel extract. The inhibition zone of the phytogenic AgNPs on E. coli reached 17.53, 22.35, and 26.06 mm at (0.1, 0.5, and 1) mg/ml respectively. While inhibition zones of Punica warm aqueous extract reached 5.33, 10.63, and 16.08 mm at the same concentrations. phytogenic AgNPs gave smaller inhibition zones in gram-positive than gram- negative. Cytotoxic activity of the phytogenic AgNPs was assayed in vitro agaist human blood erythrocytes (RBCs), spectroscopic results showed absorbance at 540 nm hemolysis was observed. In general, AgNPs showed least RBCs hemolysis percentage, at 1 mg/ml concentration, hemolysis percentage was (4.50%). This study, concluded that the Punica granatum peel extract has the power of synthses of AgNPs characterized by broad spectrum antimicrobial activity with cyto-toxicity proportional to AgNPs concentration.

Identification of a New Antimicrobial Agent against Bovine Mastitis-Causing Staphylococcus aureus

Staphylococcus aureus RF122 is a major pathogen that causes bovine mastitis, which is the most prevalent and costly disease in the milk and dairy industry. S. aureus expresses various virulence factors that are especially highly associated with iron metabolism, and the bacterial ferrous iron transport system Feo is important for bacterial growth or virulence in mammalian hosts. In this study, we evaluated a new antimicrobial agent, PHT-427, targeting the S. aureus RF122 Feo system for the prevention of bovine mastitis. Various analyses on in vitro enzymatic assays, growth inhibition, virulence expressions, and toxicity of animal model systems were conducted to characterize the inhibition properties of PHT-427. This small molecule efficiently inhibited enzyme activity of FeoB and bacterial growth. PHT-427 attenuated various virulence factors related to milk quality, including staphyloxanthin production, biofilm formation, and coagulation. Considering the high frequency of antibiotic-resistant S. aureus in bovine mastitis isolates, PHT-427 synergistically enhanced bacterial antibiotic susceptibility and further inhibited global Gram-positive bacterial growth. Unlike its effects on bacteria, the inhibitor did not show any toxicity on animal model systems. These results indicate that the S. aureus Feo system represents a good target for antimicrobial strategies, and this new antimicrobial agent may represent a promising biotechnological application for preventing S. aureus-induced bovine mastitis in the milk and dairy industry.

The analysis of the antimicrobial benefits of Populus balsamifera

This study was conducted to explore a new potential treatment for bacterial infections. This study aimed to investigate the antimicrobial properties of the tree species, Populus balsamifera. The objective was to determine the effectiveness of extract from the buds of P. balsamifera in inhibiting bacterial growth. A Kirby-Bauer assay was used to assess the efficacy of P. balsamifera extract against gram-negative and gram-positive bacterial growth. It was observed that the extract of the buds of P. balsamifera was highly effective against gram-positive bacteria. This helps to indicate the potential use of P. balsamifera in the medical field to eliminate gram-positive bacteria.

Improving Photocatalytic and Antibacterial Properties of Zein/Polyvinyl Alcohol Polymer Composite Film by Dispersing TiO2 Nano Particles

Zein/polyvinyl alcohol/nano-TiO 2 composite film was effectively blended using a solution casting method. Mechanical, photocatalytic, and antibacterial properties of the composite film were evaluated. The breaking elongation of the composite film increased up to the maximum loading of 0.4% of nano-TiO 2 . The humidity and moisture content relationship was estimated with standard modified models of Halsey, Oswin, Chung Pfost, and Henderson. It was found that the Halsey model was the most suitable mathematical model to predict the effect of humidity on moisture absorption of zein/PVA/nano-TiO 2 composite film. The dispersion of nanoparticles in the composite film was evidenced by a field emission scanning electron microscope. In addition, the film was thermally stable up to a temperature of 200 o C, indicated by a thermographic analyzer. Methyl orange photocatalytic degradation met kinetics of the 1 st order reaction with a total degraded amount of 92 percent. Moreover, the role of TiO 2 nanoparticles in the composite film has a remarkable effect on the inhibition of gram-positive and negative bacterial growth. The synthesized film can be a possible alternative for production of surface protective packaging material.

Assessing the Validity of the Storage of Sterilized Surgical Instruments Steam under Pressure

The chronological order of validity of sterile material is indicative adopted by hospitals for the use of hospital instruments after sterilization, intending to maintain sterility and to ensure the environmental conditions of storage, handling, and transportation. This study aimed to evaluate the sterility validity of surgical instruments stored in the sterilization center regarding the feasibility of their safe use over time. Fifteen surgical forceps were sterilized in aseptic (surgical grade) paper and polypropylene blankets packaging and stored in the arsenal of a large hospital. The materials were tested monthly in a laminar flow cabinet to test how long the surgical instruments remained sterile. Sterility tests showed no gram-positive or gram-negative bacterial or fungal microbiological growth from any of the samples evaluated according to storage time (30, 60, 90, and 120 days). Sterile instruments can be safely used for up to 120 days, thus saving costs by avoiding the repacking of those items.

Pleural space infection bacteriology and clinical, laboratory, and physical outcomes

Introduction and Objectives: Even with the development of powerful medicines, bacterial pneumonia remains a leading cause of death and disability. The goal of this article is to discuss the bacteriology of pleural space infection and to identify the parameters that would predict infection outcome in different types of parapneumonic effusion.Materials and Methods: Observational study of patients diagnosed with simple, difficult, or complex parapneumonic effusion who were admitted at the Department of Respiratory Medicine, Mamata Medical College, Khammam, Telangana, India, between March 2019 to September 2019. Gram staining and culture growth of pleural fluid was examined to characterised the bacteria that cause pleural space infection. Multiple logistic regressions were used to statistically analyse the data and draw comparisons between the two outcomes.Results: Multiple logistic regression models and a univariate model were utilised. Comparable gram-positive and gram-negative bacterial growth was seen in this study of pleural space infections. pH, loculation, positive stain, culture, fever, and serum albumin were all statistically significant in independent analyses. Tube thoracostomy success or failure was significantly predicted by PH, loculation, and serum albumin in a multivariate analysis.Conclusion: Predictive indicators for the prognosis of difficult and complex parapneumonic effusion included pleural fluid pH, loculation, and serum albumin in a multivariate analysis. They may be put to use in sending patients on to more permanent care.

Evaluation and comparison between the bactericidal effect of diode laser irradiation (970 nm) and silver nanoparticles on Enterococcus faecalis bacterial strain (an in vitro study)

Background/AimsToday, the using of diode lasers in dentistry has made a significant progress; it increased the speed of treatment, decreased the time of healing, and showed a bactericidal effect. The thermal effects should be considered in root canal treatment by laser, as the temperature rises to critical levels, causing tissues damage and any thermal change occurs after laser irradiation. The temperature can rise up to 10 °C above the body temperature for less than 2–3 min without damaging the periodontal tissue or burring the tooth structure by using cooling. Antibacterial properties of silver nanoparticles (Ag-NPs) were reducing Gram-positive and Gram-negative bacterial growth, due to a larger surface to volume ratio of nanoparticles. The goal of this study is to evaluate the bactericidal effect of diode laser irradiation (970 nm), the silver nanoparticles in root canals infected by Enterococcus faecalis bacteria, and the thermal change that occurs after laser application.Materials and methodsForty-five extracted single-rooted human maxillary anterior teeth were collected and used as a container for the test. The samples are inoculated by Enterococcus faecalis bacterial strain and randomly divided into three groups: group I (control) (n = 15), group II (Enterococcus faecalis bacteria and silver nanoparticles) (n = 15), and group III (Enterococcus faecalis bacteria and diode laser) (n = 15). The laser group was divided into subgroups according to the time of laser irradiation (20 s, 30 s, and 40 s).ResultsThere was a significant difference between the treated groups, in which the laser group showed a high bactericidal effect than the other groups at the time of radiation 40 s, without damaging the tooth structure or periodontal ligament.ConclusionDiode laser with proper parameters is used as an adjunctive endodontic disinfection modality due to its antibacterial effect with a temperature tolerated by periodontal tissues with safety limit.

Synthesis of boron cluster analogs of penicillin and their antibacterial activity

Antimicrobial resistance (AMR) is an exceptional increasing challenge for human health; it is urgently need to develop novel leads that can be developed to clinically useful drugs. The idea to modify old class of antibiotics that has been a cornerstone of medical has been dramatically refreshed searching for ways to overcome antibiotic-resistant bacteria. A very interesting development is the implementation of carboranes in design of pharmacologically active molecules. A series of novel penicillin G analogs bearing lipophilic 1,2-dicarba-closo-dodecaborane (ortho-carborane), 1,7-dicarba-closo-dodecaborane (meta-carborane), or 1,12-dicarba-closo-dodecaborane (para-carborane) boron clusters, instead of the phenyl ring, were synthesized. The boron-cluster penicillin G analogs were obtained via amidation of 6-aminopenicillanic acid (6-APA) with N-succinimidyl active esters containing ortho-, meta-, or para-carborane Alternatively, analogs containing ortho- or para-carborane were synthesized using ortho- or para-carborane cluster acid chlorides. The compounds thus obtained were tested in vitro against gram-positive bacteria Staphylococcus aureus and gram-negative bacteria Klebsiella pneumoniae, Enterobacter cloacae, Acinetobacter baumanii, and Pseudomonas aeruginosa. The most potent inhibitor of gram-positive bacterial growth was compound 9, bearing a para-carborane cluster. Compounds 7 and 8 bearing ortho- or metha-carborane, respectively, were less active against S. aureus.