Insight into multidrug-resistant microorganisms from microbial infected diabetic foot ulcers

Curcumin-Polyethylene Glycol Loaded on Chitosan-Gelatin Nanoparticles Enhances Infected Wound Healing

The aim of the present study was to evaluate effects of curcumin-polyethylene glycol loaded on chitosan-gelatin nanoparticles (C-PEG-CGNPs) on healing of methicillin-resistant Staphylococcus aureus (MRSA)-infected wounds in rat as a model study. Forty male Wistar rats were randomized into 5 groups of 8 animals each. In CNTRL group, no infected/no treated wounds were covered with sterile saline 0.9% solution (0.1 mL). In MRSA group, MRSA-infected wounds were only treated with sterile saline 0.9% solution (0.1 mL). In MRSA/CP group, 0.1 mL curcumin nanoparticles (1 mg/mL) was applied topically to treat MRSA-infected wounds. In MRSA/CG group, 0.1 mL CG (1 mg/mL) was applied topically to treat MRSA-infected wounds. In MRSA/CP-CG group, 0.1 mL CP-CG (1 mg/mL) was applied topically to treat MRSA-infected wounds. Microbiological examination; planimetric, biochemical, histological, morphometric studies, angiogenesis, hydroxyproline levels, and reverse transcription polymerase chain reaction for caspase 3, Bcl-2, and p53 showed significant difference between rats in MRSA/CP-CG group in comparison with other groups (P < .05). Accelerated and improved healing in wounds infected with MRSA were observed in animals treated with C-PEG-CGNPs. Via increasing solubility of curcumin in C-PEG-CGNP, this harmless and easily available composition could be considered to be topically applied in infected wounds.

Formulation of novel bioactive gelatin inspired by cinnamaldehyde for combating multi-drug resistant bacteria: Characterization, molecular docking, pharmacokinetic analyses, and in vitro assessments

This study set out to formulate antibacterial and antioxidant gelatin boosted by cinnamaldehyde for combating multi-drug resistant bacteria previously obtained from chronic wounds. Towards this end, gelatin amine groups were conjugated with carbonyl groups of cinnamaldehyde, producing cinnamyl-gelatin Schiff bases. The physicochemical attributes of cinnamyl-gelatin Schiff bases were probed concerning alterations in chemical structures and microstructures compared to native gelatin. Besides, cinnamyl-gelatin Schiff bases exhibited higher thermal stability than gelatin, with a diminishing in solubility due to increases in hydrophobicity features. Interestingly, cinnamyl-gelatin derivatives exerted antibacterial activities versus multi-drug resistant Gram-negative and Gram-positive bacteria, showing maximum growth inhibition at the highest concentration of cinnamaldehyde incorporated into gelatin. The scavenging activities of gelatin against DPPH and ABTS•+ were promoted in cinnamyl-gelatin derivatives from 11.93 ± 0.6 % to 49.9 ± 2.5 % and 12.54 ± 0.63 % to 49.9 ± 3.12 %, respectively. Remarkably, cinnamyl-gelatin derivatives induced the proliferation of fibroblast cells, implying their prospective applications in tissue engineering. Molecular docking and pharmacokinetic investigations disclosed the potential antibacterial mechanisms of cinnamyl-gelatin derivatives alongside their biopharmaceutical applications. Altogether, these findings suggest that cinnamyl-gelatin derivatives could be utilized to tailor antibacterial-free antibiotics and antioxidant wound dressings against virulent bacteria to promote chronic wound recovery.

Microbiological Pattern, Antimicrobial Resistance and Prevalence of MDR/XDR Organisms in Patients With Diabetic Foot Infection in an Indian Tertiary Care Hospital

Foot infections are the most prevalent problem in persons with diabetes. The burden of multidrug resistant (MDR) microorganisms in diabetic foot infections (DFIs) is rising day by day. Given that, the present study aims to determine the variety of microorganisms isolated from the diabetic foot ulcers (DFUs), and their antibiotic sensitivity pattern. This prospective observational study was conducted for 1 year at Bharati Hospital and Research Centre, Pune, India. Clinically infected patients with DFU admitted to the surgery ward were included in this study. The specimen for microbiological studies is obtained from the wound swabs, soft tissue, and bone tissue as a part of routine clinical care. All demographic, clinical data, microbial culture results were collected, and evaluated for each case. Antimicrobial susceptibility testing to different agents was carried out using the VITEK-2® machine. A total of 110 microorganisms were isolated from 76 specimens, with an average of 1.4 organisms per lesion. Staphylococcus aureus (n = 27, 24.5%) and Escherichia coli (n = 17, 15.4%) were the most prevalent Gram-positive and Gram-negative organisms isolated, respectively. MDR organisms constituted up to 52 (47.2%), while 6 (5.4%) of the samples were extensively drug resistant (XDR). Methicillin-resistant S aureus (MRSA) accounted for up to 19 (70.3%) of the S aureus isolates, likewise extended-spectrum beta-lactamase producing microorganisms constituted 16 (14.5%) of total isolates in this study. Oxacillin and benzyl penicillin exhibited least susceptibility against Gram-positive bacteria, among Gram-negative organisms; cefuroxime, ceftriaxone, and ciprofloxacin were least sensitive. As most of the S aureus isolate in our study was MRSA, empirical antimicrobial therapy may include coverage for MRSA in a patient with risk factors associated with this pathogen. A crucial observation is the presence of XDR strains of Proteus mirabilis in DFIs, which is resistant to almost all the antimicrobials, tested. Appropriate antimicrobial selection may reduce the morbidity and the emergence of MDR organisms in DFIs.

Effect of hyperbaric oxygen treatment on diabetic foot ulcers: A meta-analysis

The meta-analysis aimed to assess the effect of hyperbaric oxygen treatment on diabetic foot ulcers. Using dichotomous or contentious random or fixed effect models, the outcomes of this meta-analysis were examined and the odds ratio (OR) and the mean difference (MD) with 95% confidence intervals (CIs) were computed. 17 examinations from 1992 to 2022 were enrolled for the present meta-analysis, including 7219 people with diabetic foot ulcers. Hyperbaric oxygen treatment had a significantly higher healed ulcer (OR, 14.39; 95% CI, 4.02-51.52, p < 0.001), higher adverse event (OR, 2.14; 95% CI, 1.11-4.11, p = 0.02), lower mortality (OR, 0.22; 95% CI, 0.07-0.71, p = 0.01) and higher ulcer area reduction (MD, 23.39; 95% CI, 11.79-34.99, p < 0.001) compared to standard treatment in patients with diabetic foot ulcers. However, hyperbaric oxygen treatment and standard treatment had no significant difference in amputation (OR, 0.62; 95% CI, 0.22-1.75, p = 0.37), major amputation (OR, 0.59; 95% CI, 0.18-1.92, p = 0.38), minor amputation (OR, 0.64; 95% CI, 0.15-2.66, p = 0.54) and healing time (MD, -0.001; 95% CI, -0.76 to 0.75, p = 0.99) in patients with diabetic foot ulcers. The examined data revealed that hyperbaric oxygen treatment had a significantly higher healed ulcer, adverse event, and ulcer area reduction and lower mortality, however, there was no significant difference in amputation and healing time compared to standard treatment in patients with diabetic foot ulcers. Yet, attention should be paid to its values since most of the selected examinations had a low sample size and some of the comparisons had a low number of selected studies.

A comprehensive review of recent advances in silk sericin: Extraction approaches, structure, biochemical characterization, and biomedical applications

Silks are natural polymers that have been widely used for centuries. Silk consists of a filament core protein, termed fibroin, and a glue-like coating substance formed of sericin (SER) proteins. This protein is extracted from the silkworm cocoons (particularly Bombyx mori) and is mainly composed of amino acids like glycine, serine, aspartic acid, and threonine. Silk SER can be obtained using numerous methods, including enzymatic extraction, high-temperature, autoclaving, ethanol precipitation, cross-linking, and utilizing acidic, alkali, or neutral aqueous solutions. Given the versatility and outstanding properties of SER, it is widely fabricated to produce sponges, films, and hydrogels for further use in diverse biomedical applications. Hence, many authors reported that SER benefits cell proliferation, tissue engineering, and skin tissue restoration thanks to its moisturizing features, antioxidant and anti-inflammatory properties, and mitogenic effect on mammalian cells. Remarkably, SER is used in drug delivery depending on its chemical reactivity and pH-responsiveness. These unique features of SER enhance the bioactivity of drugs, facilitating the fabrication of biomedical materials at nano- and microscales, hydrogels, and conjugated molecules. This review thoroughly outlines the extraction techniques, biological properties, and respective biomedical applications of SER.

The Synergistic Influence of Polyflavonoids from Citrus aurantifolia on Diabetes Treatment and Their Modulation of the PI3K/AKT/FOXO1 Signaling Pathways: Molecular Docking Analyses and In Vivo Investigations

This study was aimed at probing the modulatory influence of polyflavonoids extracted from Citrus aurantifolia, lemon peel extract (LPE-polyflavonoids), on attenuating diabetes mellitus (DM) and its complications. HPLC investigations of the LPE exhibited the incidence of five flavonoids, including diosmin, biochanin A, hesperidin, quercetin, and hesperetin. The in silico impact on ligand-phosphatidylinositol 3-kinase (PI3K) interaction was investigated in terms of polyflavonoid class to explore the non-covalent intakes and binding affinity to the known protein active site. The drug likeness properties and pharmacokinetic parameters of the LPE-polyflavonoids were investigated to assess their bioavailability in relation to Myricetin as a control. Remarkably, the molecular docking studies demonstrated a prominent affinity score of all these agents together with PI3K, implying the potency of the extract to orchestrate PI3K, which is the predominant signal for lessening the level of blood glucose. To verify these findings, in vivo studies were conducted, utilizing diabetic male albino rats treated with LPE-polyflavonoids and other groups treated with hesperidin and diosmin as single flavonoids. Our findings demonstrated that the LPE-polyflavonoids significantly ameliorated the levels of glucose, insulin, glycogen, liver function, carbohydrate metabolizing enzymes, G6Pd, and AGEs compared to the diabetic rats and those exposed to hesperidin and diosmin. Furthermore, the LPE-polyflavonoids regulated the TBARS, GSH, CAT, TNF-α, IL-1β, IL-6, and AFP levels in the pancreatic and hepatic tissues, suggesting their antioxidant and anti-inflammatory properties. In addition, the pancreatic and hepatic GLUT4 and GLUT2 were noticeably increased in addition to the pancreatic p-AKT in the rats administered with the LPE-polyflavonoids compared to the other diabetic rats. Remarkably, the administration of LPE-polyflavonoids upregulated the expression of the pancreatic and hepatic PI3K, AMPK, and FOXO1 genes, emphasizing the efficiency of the LPE in orchestrating all the signaling pathways necessitated to reduce the diabetes mellitus. Notably, the histopathological examinations of the pancreatic and hepatic tissues corroborated the biochemical results. Altogether, our findings accentuated the potential therapeutic role of LPE-polyflavonoids in controlling diabetes mellitus.

Functionalization of chitosan with poly aromatic hydroxyl molecules for improving its antibacterial and antioxidant properties: Practical and theoretical studies

In this study, the chitosan backbone was functionalized with 2,2',4,4'-tetrahydroxybenzophenone by Schiff base, bonding the molecules into the repeating amine groups. The use of ¹H NMR, FT-IR, and UV-Vis analyses provided compelling evidence of the structure of the newly developed derivatives. The deacetylation degree was calculated to be 75.35 %, and the degree of substitution was 5.53 % according to elemental analysis. The thermal analysis of samples using TGA demonstrated that CS-THB derivatives are more stable than chitosan itself. SEM was used to investigate the change in surface morphology. The improvement of the biological properties of chitosan was investigated in terms of its antibacterial activity against pathogenic antibiotic-resistant bacteria. The antioxidant properties showed an improvement in activity compared to chitosan by two times against ABTS radicals and four times against DPPH radicals. Furthermore, the cytotoxicity and anti-inflammatory properties were investigated using normal skin cells (HBF4) and WBCs. Quantum chemistry calculations revealed that combining polyphenol with chitosan makes it more effective as an antioxidant than either chitosan or polyphenol alone. Our findings suggest that the new chitosan Schiff base derivative could be utilized for tissue regeneration applications.

Synthesis and physicochemical properties of an aromatic chitosan derivative: In vitro antibacterial, antioxidant, and anticancer evaluations, and in silico studies

This study was designed to synthesize a functionalized chitosan by coupling the amine groups of chitosan with 2,4,6-Trimethoxybenzaldehyde, producing a chitosan Schiff base (Cs-TMB). The development of Cs-TMB was verified employing FT-IR, ¹H NMR, the electronic spectrum, and elemental analysis. Antioxidant assays exhibited significant ameliorations of Cs-TMB, reporting scavenging activities of 69.67 ± 3.48 % and 39.65 ± 1.98 % for ABTS^•+ and DPPH, respectively, while native chitosan showed scavenging ratios of 22.69 ± 1.13 % and 8.24 ± 0.4.1 % toward ABTS^•+ and DPPH, respectively. Besides, Cs-TMB exerted significant antibacterial activity up to 90 % with remarkable bactericidal capacity against virulent gram-negative and gram-positive bacteria compared to the original chitosan. Furthermore, Cs-TMB exhibited a safe profile against normal fibroblast cells (HFB4). Interestingly, flow cytometric analysis showed that Cs-TMB demonstrated prominent anticancer properties of 52.35 ± 2.99 % against human skin cancer cells (A375), compared to 10.66 ± 0.55 % for Cs-treated cells. Moreover, Python and PyMOL in-house scripts were used to predict the interaction of Cs-TMB with the adenosine A1 receptor and visualized as a protein-ligand system submerged in a lipid membrane. Overall, these findings accentuate that Cs-TMB could be a favorable representative for wound dressing formulations and skin cancer treatment.

Review and analysis of the overlapping threats of carbapenem and polymyxin resistant E. coli and Klebsiella in Africa

BACKGROUND

Carbapenem-resistant Enterobacterales are among the most serious antimicrobial resistance (AMR) threats. Emerging resistance to polymyxins raises the specter of untreatable infections. These resistant organisms have spread globally but, as indicated in WHO reports, the surveillance needed to identify and track them is insufficient, particularly in less resourced countries. This study employs comprehensive search strategies with data extraction, meta-analysis and mapping to help address gaps in the understanding of the risks of carbapenem and polymyxin resistance in the nations of Africa.

METHODS

Three comprehensive Boolean searches were constructed and utilized to query scientific and medical databases as well as grey literature sources through the end of 2019. Search results were screened to exclude irrelevant results and remaining studies were examined for relevant information regarding carbapenem and/or polymyxin(s) susceptibility and/or resistance amongst E. coli and Klebsiella isolates from humans. Such data and study characteristics were extracted and coded, and the resulting data was analyzed and geographically mapped.

RESULTS

Our analysis yielded 1341 reports documenting carbapenem resistance in 40 of 54 nations. Resistance among E. coli was estimated as high (> 5%) in 3, moderate (1-5%) in 8 and low (< 1%) in 14 nations with at least 100 representative isolates from 2010 to 2019, while present in 9 others with insufficient isolates to support estimates. Carbapenem resistance was generally higher among Klebsiella: high in 10 nations, moderate in 6, low in 6, and present in 11 with insufficient isolates for estimates. While much less information was available concerning polymyxins, we found 341 reports from 33 of 54 nations, documenting resistance in 23. Resistance among E. coli was high in 2 nations, moderate in 1 and low in 6, while present in 10 with insufficient isolates for estimates. Among Klebsiella, resistance was low in 8 nations and present in 8 with insufficient isolates for estimates. The most widespread associated genotypes were, for carbapenems, blaOXA-48, blaNDM-1 and blaOXA-181 and, for polymyxins, mcr-1, mgrB, and phoPQ/pmrAB. Overlapping carbapenem and polymyxin resistance was documented in 23 nations.

CONCLUSIONS

While numerous data gaps remain, these data show that significant carbapenem resistance is widespread in Africa and polymyxin resistance is also widely distributed, indicating the need to support robust AMR surveillance, antimicrobial stewardship and infection control in a manner that also addresses broader animal and environmental health dimensions.

Therapeutic potential of two formulated novel chitosan derivatives with prominent antimicrobial activities against virulent microorganisms and safe profiles toward fibroblast cells

The development of new antimicrobial agents has been drawing considerable attention due to the extreme escalation of multi-drug resistant microorganisms. We thus sought to ameliorate the antimicrobial activities of the chitosan (Cs) biopolymer by coupling chitosan with cyclohexanone and 2-N-methyl pyrrolidone, synthesizing two novel Schiff bases (CsSB1 and CsSB2), respectively. FT-IR, TGA, DSC, SEM, and potentiometric titration were employed to characterize the formulated chitosan derivatives. The findings exposed that the degrees of deacetylation were 88.12% and 89.98% for CsSB1 and CsSB2, respectively. The antimicrobial capacities of CsSB1 and CsSB2 were substantially enhanced compared with prime chitosan. Furthermore, the CsSB1 and CsSB2 demonstrated minimum inhibitory concentrations (MIC) of 50 µg/ml in relation to all studied microorganisms, whereas chitosan revealed MIC value of 50 µg/ml only for E. coli. Furthermore, CsSB1 with a concentration of 250 µg/ml manifested the highest antibacterial activity against Gram-positive bacteria. Correspondingly, CsSB2 revealed a comparable trend of microbial hindrance with lower activities. Besides, the two derivatives could thwart the growth of Candida albicans (C. albicans). The cytotoxicity assay of the biomaterials accentuated their biocompatibility with fibroblasts. Collectively, the two formulated chitosan derivatives could competently rival the native chitosan, particularly for future applications in wound healing.

Influence of Cedar Essential Oil on Physical and Biological Properties of Hemostatic, Antibacterial, and Antioxidant Polyvinyl Alcohol/Cedar Oil/Kaolin Composite Hydrogels

Polyvinyl alcohol (PVA) is a safe and biodegradable polymer. Given the unique physical and chemical properties of PVA, we physically cross-linked PVA with kaolin (K) and cedar essential oil (Ced) using the freeze-thawing approach to fabricate PVA/Ced/K sponge hydrogels as hemostatic, antibacterial, and antioxidant wound healing materials. The physicochemical characteristics of PVA/Ced/K hydrogels, including water swelling profiles and gel fractions, were surveyed. Additionally, the functional groups of hydrogels were explored by Fourier transform infrared spectroscopy (FTIR), while their microstructures were studied using scanning electron microscopy (SEM). Furthermore, the thermal features of the hydrogels were probed by thermal gravimetric analysis (TGA) and differential scanning calorimetry (DSC). Evidently, alterations in cedar concentrations resulted in significant variations in size, water uptake profiles, and hydrolytic degradation of the hydrogels. The incorporation of cedar into the PVA/K endowed the hydrogels with significantly improved antibacterial competency against Bacillus cereus (B. cereus) and Escherichia coli (E. coli). Moreover, PVA/Ced/K exhibited high scavenging capacities toward ABTS^•+ and DPPH free radicals. Beyond that, PVA/Ced/K hydrogels demonstrated hemocompatibility and fast blood clotting performance in addition to biocompatibility toward fibroblasts. These findings accentuate the prospective implementation of PVA/Ced/K composite hydrogel as a wound dressing.

Short- and Long-Term Effects of Different Antibiotics on the Gut Microbiota and Cytokines Level in Mice

BACKGROUND

Antibiotics are the first line of treatment for infectious diseases. However, their overuse can increase the spread of drug-resistant bacteria. The present study analyzed the impact of different types of antibiotics on the gut microbiome and cytokines level of mice.

METHODS

A total of five groups of 8-week-old male BALB/c mice (n = 35) were treated with piperacillin-tazobactam (TZP), ceftriaxone (CRO), tigecycline (TGC), levofloxacin (LEV) or normal saline (Ctrl), respectively, for up to 4 weeks. Fecal samples were analyzed by bacterial 16S rRNA gene sequencing for bacterial identification. Blood samples were used for the determination of 23 serum cytokines using multiplex immunoassay.

RESULTS

Exposure to antibiotics was shown to affect the normal weight gain of mice. Significant changes in gut composition caused by TZP, CRO and TGC treatment included the decreased abundance of Bacteroidetes (p < 0.01), Muribaculaceae (p < 0.01) and Lachnospiraceae (p < 0.01), and the increased abundance of Proteobacteria (p < 0.05), Enterobacteriaceae (including Klebsiella and Enterobacter) (p < 0.01) and Enterococcaceae (including Enterococcus) (p < 0.01). After 4-week treatment, the TZP, CRO and LEV groups had significantly lower concentrations of several serum cytokines. Correlation analysis of the top 30 bacterial genera and cytokines showed that Enterococcus and Klebsiella were strongly positively correlated with tumor necrosis factor-α (TNF-α), interleukins (IL) IL-12p70 and IL-1β. Desulfovibrio, Candidatus Saccharimonas, norank_f__norank_o__Clostridia_UCG-014, Lactobacillus, and Roseburia were strongly negatively correlated with these cytokines.

CONCLUSION

This study demonstrates the effects of various antibiotics on the intestinal microflora and immune status of mice. Compared with TZP, CRO and TGC, LEV had minimal impact on the gut microbiota. In addition to TGC, long-term TZP, CRO and LEV intervention can lead to a decrease in serum cytokine levels, which may depend on the intestinal microflora, antibiotic used and the duration of treatment.

Recent advances of the nanocomposite hydrogel as a local drug delivery for diabetic ulcers

Diabetic ulcer is a serious complication of diabetes. Compared with that of healthy people, the skin of patients with a diabetic ulcer is more easily damaged and difficult to heal. Without early intervention, the disease will become increasingly serious, often leading to amputation or even death. Most current treatment methods cannot achieve a good wound healing effect. Numerous studies have shown that a nanocomposite hydrogel serves as an ideal drug delivery method to promote the healing of a diabetic ulcer because of its better drug loading capacity and stability. Nanocomposite hydrogels can be loaded with one or more drugs for application to chronic ulcer wounds to promote rapid wound healing. Therefore, this paper reviews the latest progress of delivery systems based on nanocomposite hydrogels in promoting diabetic ulcer healing. Through a review of the recent literature, we put forward the shortcomings and improvement strategies of nanocomposite hydrogels in the treatment of diabetic ulcers.

Preparation, Characterization, and Bio Evaluation of Fatty N- Hexadecanyl Chitosan Derivatives for Biomedical Applications

The objective of this study was to improve the antibacterial activities of chitosan via N-alkyl substitution using 1-bromohexadecane. Mono and di substitution (Mono-NHD-Ch and Di-NHD-Ch) were prepared and characterized using FT-IR, HNMR, TGA, DSC, and SEM. Elemental analysis shows an increase in the C/N ratio from 5.45 for chitosan to 8.63 for Mono-NHD-Ch and 10.46 for Di-NHD-Ch. The antibacterial properties were evaluated against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, and Bacillus cereus. In the examined microorganisms, the antibacterial properties of the novel alkyl derivatives increased substantially higher than chitosan. The minimum inhibitory concentration (MIC) of Mono-NHD-Ch and Di-NHD-Ch was perceived at 50 μg/mL against tested microorganisms, except for B. cereus. The MTT test was used to determine the cytotoxicity of the produced materials, which proved their safety to fibroblast cells. The findings suggest that the new N-Alkyl chitosan derivatives might be used as antibacterial alternatives to pure chitosan in wound infection treatments.

Status of Microbiota in Odontogenic Inflammatory Lesions and Dental Surgery Procedures Performed on an Outpatient Basis

Inflammations of the facial part of the skull are most commonly caused by a bacterial infection. They are a frequently occurring pathological process, which results from a rich bacterial flora of the oral cavity, as well as diseased teeth and periodontal tissues. These inflammations have a primarily mixed character with the prevalence of anaerobic bacteria. Gangrene of the dental pulp is the most common odontogenic cause. In the case of inflammations of oral tissues an early and corrective treatment results in quick recovery. The purpose of this work was to assess the efficiency of empirical antibiotic therapy applied in patients with inflammations of oral tissues on the basis of a drug susceptibility profile of bacteria isolated from material extracted from inflammatory lesions. The research material consisted of smears collected from patients with existing acute inflammations in the oral cavity. The smear was collected from the bottom of the lesion after its prior surgical treatment and pus evacuation, and again, 7 days after surgery. In patients with acute odontogenic inflammations the recommended first-line therapy are extended-spectrum penicillins, characterized by a low risk of side effects and strong antimicrobial activity. In the study group, both clindamycin and amoxicillin exhibited high efficiency in treating acute odontogenic inflammatory lesions in the oral cavity.

Quorum Sensing and Biofilm Disrupting Potential of Imidazole Derivatives in Chromobacterium violaceum Using Antimicrobial and Drug Discovery Approaches

Population of drug-resistant bacteria have increased at an alarming rate in the past few decades. The major reason for increasing drug resistance is the lack of new antibiotics and limited drug targets. It has therefore been a vital task to develop new antibiotics with different drug targets. Two such targets are biofilm formation and quorum sensing. Quorum sensing is cell to cell communication used by bacteria that initiates many important survival processes and aids in establishing pathogenesis. Both biofilm and quorum sensing are inter-related processes and play a major role in physiological and pathogenesis processes. In this study, five novel imidazole derivatives (IMA-1-IMA-5) were synthesised and tested for their antibacterial and anti-quorum sensing activities against Chromobacterium violaceum using different in silico and in vitro techniques following the standard protocols. In silico results revealed that all compounds were able to effectively bind to and interact sufficiently with the target protein CviR. CviR is a protein to which autoinducers bind to initiate the quorum sensing process. In silico results also revealed that the compounds generated favourable structural dynamics implying that the compounds would be able to effectively bind to CviR and inhibit quorum sensing. Susceptibility results revealed that IMA-1 is the most active of all the derivatives against both planktonic cells and biofilms. Qualitative and quantitative evaluation of anti-quorum sensing activity at sub-inhibitory concentrations of these compounds also revealed high activity for IMA-1. Down-regulation of most of the quorum sensing genes when cells were treated with the test compounds affirmed the high anti-quorum sensing activities of these compounds. The results from this study are promising and urges on the use of anti-quorum sensing and biofilm disrupting molecules to combat multi-drug resistance problem.

Bioactive Injectable Hydrogel Dressings for Bacteria-Infected Diabetic Wound Healing: A "Pull-Push" Approach

Chronic diabetic wound healing remains a challenge due to the existence of excessive danger molecules and bacteria in the inflammatory microenvironment. There is an urgent need for advanced wound dressings that target both inflammation and infection. Here, a bioactive hydrogel without loading any anti-inflammatory ingredients is rationally designed to achieve a "Pull-Push" approach for efficient and safe bacteria-infected diabetic wound healing by integrating danger molecule scavenging (Pull) with antibiotic delivery (Push) in the inflammatory microenvironment. The cationic hydrogel, termed the OCMC-Tob/PEI hydrogel, is fabricated by the conjugation of polyethylenimine (PEI) and tobramycin (Tob) on an oxidized carboxymethyl cellulose (OCMC) backbone via the Schiff base reaction with injectable, self-healing, and biocompatible properties. The OCMC-Tob/PEI hydrogel not only displays the remarkable capability of capturing multiple negatively charged danger molecules (e.g., cell-free DNA, lipopolysaccharides, and tumor necrosis factor-α) to ameliorate anti-inflammation effects but also achieves controllable long-term antibacterial activity by the pH-sensitive release of Tob. Consequently, this multifunctional hydrogel greatly expedites the wound closure rate with combined anti-inflammation and anti-infection effects on Pseudomonas aeruginosa-infected diabetic wounds. Our work provides a highly versatile treatment approach for chronic diabetic wounds and a promising dressing for regenerative medicine.

Chitosan-curcumin complexation to develop functionalized nanosystems with enhanced antimicrobial activity against hetero-resistant gastric pathogen

With the apparent stagnation in the antibiotic discovery and the propagation of multidrug resistance, Helicobacter pylori associated gastric infections are hard to eradicate. In pursuance of alternative medicines, in this study, covalent modification of chitosan (CS) polymer with curcumin (Cur) was accomplished. Proton Nuclear Magnetic Resonance and Fourier Transform Infrared spectroscopy elucidated the covalent interaction between Cur and CS with characteristic peak of imine functional group (C=N). Scanning Electron Microscopy provided visual proof for surface topology, while size and zeta potential values further affirmed the development of curcumin functionalized chitosan nanosystems (Cur-FCNS). The complexation efficiency of CS with Cur was found as 70 ± 3% at an optimal ratio of 5:1 for CS and Cur, respectively. Cur-FCNS developed with ionic gelation and ultrasonication method demonstrated synergistic anti-H. pylori activity in growth-kinetics and anti-biofilm assays, which was superior to free Cur and even chitosan nanosystems. Under simulated gastric conditions, Cur-FCNS revealed cumulative-release of only 16 ± 0.8% till 40 h, which indicated its improved stability to interact with H. pylori. In silico findings affirmed high binding affinity of Cur-FCNS with multiple bacterial virulence factors. Thus, our results affirmed the exceptional potential of Cur-FCNS as next-generation alternative-medicine to treat resistant H. pylori.

Zingiber officinale ameliorates diabetic nephropathy and hepatotoxicity in rats by preventing tissue injury and controlling liver/kidney function

BACKGROUND: Chronic hyperglycemia results in decrease glucose metabolism leading to nephropathy, hepatotoxicity and neuropathy. Diabetic complications are regarded globally as one of the leading cause of disability and mortality. OBJECTIVE: The study aims to evaluate the role of Zingiber officinale (ZO) on diabetic nephropathy and hepatotoxicity in rats. METHODS: Thirty diabetic rats and six non-diabetic rats were distributed into six groups (n = 6). Group 1 & 2 (nondiabetic and diabetic) received distilled water at 1 ml/kg. Groups 3–5 received (12.5, 25& 50) mg/kg of ZO respectively while group 6 received 100 mg/kg metformin. All treatments lasted for 28 days and rats were euthanized on day 29. Biochemical parameters, kidney and liver histology were evaluated. RESULTS: No significant change (P >  0.05) was noticed in blood glucose and creatinine levels of diabetic rats treated with 25 mg/kg ZO compared to control. The liver of 25 mg/kg ZO treated diabetic rats showed mild distortion of hepatocytes while kidneys of ZO treated diabetic rats showed mild distortion of renal tubules with few collagen deposits and intact Bowman’s capsule. CONCLUSIONS: ZO ameliorates diabetic complications by regulating biochemical parameters and preventing renal tubules and hepatocytes damage in rats.

Engineered Nanotechnology: An Effective Therapeutic Platform for the Chronic Cutaneous Wound

The healing of chronic wound infections, especially cutaneous wounds, involves a complex cascade of events demanding mutual interaction between immunity and other natural host processes. Wound infections are caused by the consortia of microbial species that keep on proliferating and produce various types of virulence factors that cause the development of chronic infections. The mono- or polymicrobial nature of surface wound infections is best characterized by its ability to form biofilm that renders antimicrobial resistance to commonly administered drugs due to poor biofilm matrix permeability. With an increasing incidence of chronic wound biofilm infections, there is an urgent need for non-conventional antimicrobial approaches, such as developing nanomaterials that have intrinsic antimicrobial-antibiofilm properties modulating the biochemical or biophysical parameters in the wound microenvironment in order to cause disruption and removal of biofilms, such as designing nanomaterials as efficient drug-delivery vehicles carrying antibiotics, bioactive compounds, growth factor antioxidants or stem cells reaching the infection sites and having a distinct mechanism of action in comparison to antibiotics—functionalized nanoparticles (NPs) for better incursion through the biofilm matrix. NPs are thought to act by modulating the microbial colonization and biofilm formation in wounds due to their differential particle size, shape, surface charge and composition through alterations in bacterial cell membrane composition, as well as their conductivity, loss of respiratory activity, generation of reactive oxygen species (ROS), nitrosation of cysteines of proteins, lipid peroxidation, DNA unwinding and modulation of metabolic pathways. For the treatment of chronic wounds, extensive research is ongoing to explore a variety of nanoplatforms, including metallic and nonmetallic NPs, nanofibers and self-accumulating nanocarriers. As the use of the magnetic nanoparticle (MNP)-entrenched pre-designed hydrogel sheet (MPS) is found to enhance wound healing, the bio-nanocomposites consisting of bacterial cellulose and magnetic nanoparticles (magnetite) are now successfully used for the healing of chronic wounds. With the objective of precise targeting, some kinds of “intelligent” nanoparticles are constructed to react according to the required environment, which are later incorporated in the dressings, so that the wound can be treated with nano-impregnated dressing material in situ. For the effective healing of skin wounds, high-expressing, transiently modified stem cells, controlled by nano 3D architectures, have been developed to encourage angiogenesis and tissue regeneration. In order to overcome the challenge of time and dose constraints during drug administration, the approach of combinatorial nano therapy is adopted, whereby AI will help to exploit the full potential of nanomedicine to treat chronic wounds.

Bacteriological Profile and Antibiotic Susceptibility Pattern of Diabetic Foot Infection in a Tertiary Care Hospital in Lampung, Indonesia

Background

Diabetic foot infection (DFI) is a serious complication of diabetes mellitus and identification of the causative bacteria is an essential step in selecting the appropriate antibiotic therapy. This study aimed to evaluate the bacterial pattern and antibiotic susceptibility of the bacteria causing DFI in Lampung Province in Indonesia.

Methods

This study is a retrospective study reviewing the medical records of DFI patients admitted to the Dr Hi Abdul Moeloek Regional General Hospital in 2017–2019. DFI patients with complete medical record data were included in this study. Demographic, clinical, laboratory, wound culture and antibiotic susceptibility data were collected from the medical records using a short structural chart. The data obtained then reviewed.

Results

In this study, 131 DFI patients met the study criteria and were included. Based on the wound culture results, Gram-negative bacteria were obtained in 112 (85.5%) subjects with Enterobacter spp. as the predominant bacteria. Gram-positive bacteria were found in 19 (14.5%) subjects with Staphylococcus spp. as the predominant bacteria. Gram-negative bacteria found in this study showed high susceptibility to amikacin, meropenem and sulbactam/cefoperazone. Meanwhile, the Gram-positive bacteria showed high susceptibility to meropenem, sulbactam/cefoperazone and amikacin.

Conclusion

The findings of the study revealed Enterobacter spp. as the most predominant bacteria causing DFI in the studied population. The highest antibiotic susceptibility was seen for amikacin, meropenem and sulbactam/cefoperazone.

Accelerative Effect of Cinnamon Nanoparticles as well as HAMLET on Healing of Wounds Infected with MRSA in Diabetic Rats

Objective

The aim of the present study was to investigate the effect of cinnamon nanoparticles (CNPs) on healing of wounds infected with methicillin-resistant Staphylococcus aurous with human alpha-lactalbumin made lethal to tumor cells sensitization in diabetic rats.

Methods

We included fifty diabetic male rats and divided them into 5 groups. There were 10 rats in each group as follows: CONTROL group: we did not infect the CONTROL group. The wound was only covered with sterile saline 0.9% solution (0.1 mL). INFCTD group: in this group, the wounds were infected with MRSA and covered with sterile saline 0.9% solution (0.1 mL). INFCTD-HMLT group: in this group, the wounds were infected with MRSA and HAMLET (100 μg). INFCTD-CNM group: in this group, the wounds were infected with MRSA and 0.1 mL CNPs (1 mg/mL) were applied topically to wounds. INFCTD-HMLT-CNM group: in this group, the wounds were infected with MRSA, HAMLET (100 μg), and 0.1 mL CNPs (1 mg/mL).

Results

Bacteriology, wound area reduction measurements, biochemistry, histomorphometrical studies, hydroxyproline levels, and reverse transcription polymerase chain reaction for caspase-3, Bcl-2, and p53 showed significant difference between rats in the INFCTD-HMT-CNM group in comparison with other groups (P < 0.05).

Conclusions

Accelerated healing of diabetic wounds infected with MRSA showed that local application of cinnamon nanoparticles along with HAMLET sensitization on S. aureus-infected wound could be taken into consideration.

Prevalence, antimicrobial resistance profile, and characterization of multi-drug resistant bacteria from various infected wounds in North Egypt

Multi-drug resistant (MDR) bacteria associated with wounds are extremely escalating. This study aims to survey different wounds in Alexandria hospitals, North Egypt, to explore the prevalence and characteristics of MDR bacteria for future utilization in antibacterial wound dressing designs. Among various bacterial isolates, we determined 22 MDR bacteria could resist different classes of antibiotics. The collected samples exhibited the prevalence of mono-bacterial infections (60%), while 40% included poly-bacterial species due to previous antibiotic administration. Moreover, Gram-negative bacteria showed dominance with a ratio of 63.6%, while Gram-positive bacteria reported 36.4%. Subsequently, the five most virulent bacteria were identified following the molecular approach by 16S rRNA and physiological properties using the VITEK 2 automated system. They were deposited in GenBank as Staphylococcus haemolyticus MST1 (KY550377), Pseudomonas aeruginosa MST2 (KY550378), Klebsiella pneumoniae MST3 (KY550379), Escherichia coli MST4 (KY550380), and Escherichia coli MST5 (KY550381). In terms of isolation source, S. haemolyticus MST1 was isolated from a traumatic wound, while P. aeruginosa MST2 and E. coli MST4 were procured from hernia surgical wounds, and K. pneumoniae MST3 and E. coli MST5 were obtained from diabetic foot ulcers. Antibiotic sensitivity tests exposed that K. pneumoniae MST3, E. coli MST4, and E. coli MST5 are extended-spectrum β-lactamases (ESBLs) bacteria. Moreover, S. haemolyticus MST1 belongs to the methicillin-resistant coagulase-negative staphylococcus (MRCoNS), whereas P. aeruginosa MST2 exhibited resistance to common empirical bactericidal antibiotics. Overall, the study provides new insights into the prevalent MDR bacteria in Egypt for further use as specific models in formulating antibacterial wound dressings.

Development of Polyvinyl Alcohol/Kaolin Sponges Stimulated by Marjoram as Hemostatic, Antibacterial, and Antioxidant Dressings for Wound Healing Promotion

The predominant impediments to cutaneous wound regeneration are hemorrhage and bacterial infections that lead to extensive inflammation with lethal impact. We thus developed a series of composite sponges based on polyvinyl alcohol (PVA) inspired by marjoram essential oil and kaolin (PVA/marjoram/kaolin), adopting a freeze-thaw method to treat irregular wounds by thwarting lethal bleeding and microbial infections. Microstructure analyses manifested three-dimensional interconnected porous structures for PVA/marjoram/kaolin. Additionally, upon increasing marjoram and kaolin concentrations, the pore diameters of the sponges significantly increased, recording a maximum of 34 ± 5.8 µm for PVA-M0.5-K0.1. Moreover, the porosity and degradation properties of PVA/marjoram/kaolin sponges were markedly enhanced compared with the PVA sponge with high swelling capacity. Furthermore, the PVA/marjoram/kaolin sponges exerted exceptional antibacterial performance against Escherichia coli and Bacillus cereus, along with remarkable antioxidant properties. Moreover, PVA/marjoram/kaolin sponges demonstrated significant thrombogenicity, developing high thrombus mass and hemocompatibility, in addition to their remarkable safety toward fibroblast cells. Notably, this is the first study to our knowledge investigating the effectiveness of marjoram in a polymeric carrier for prospective functioning as a wound dressing. Collectively, the findings suggest the prospective usage of the PVA-M0.5-K0.1 sponge in wound healing for hemorrhage and bacterial infection control.

Oxygen-Releasing Composites: A Promising Approach in the Management of Diabetic Foot Ulcers

In diabetes, lower extremity amputation (LEA) is an irreversible diabetic-related complication that easily occurs in patients with diabetic foot ulcers (DFUs). Because DFUs are a clinical outcome of different causes including peripheral hypoxia and diabetic foot infection (DFI), conventional wound dressing materials are often insufficient for supporting the normal wound healing potential in the ulcers. Advanced wound dressing development has recently focused on natural or biocompatible scaffolds or incorporating bioactive molecules. This review directs attention to the potential of oxygenation of diabetic wounds and highlights current fabrication techniques for oxygen-releasing composites and their medical applications. Based on different oxygen-releasable compounds such as liquid peroxides and solid peroxides, for example, a variety of oxygen-releasing composites have been fabricated and evaluated for medical applications. This review provides the challenges and limitations of utilizing current oxygen releasable compounds and provides perspectives on advancing oxygen releasing composites for diabetic-related wounds associated with DFUs.

High prevalence of multiple antibiotic resistance in clinical E. coli isolates from Bangladesh and prediction of molecular resistance determinants using WGS of an XDR isolate

Multi-drug-resistance (MDR) is a severe public health concern worldwide, and its containment is more challenging in developing countries due to poor antimicrobial resistance (AMR) surveillance and irrational use of antibiotics. The current study investigated 100 clinical E. coli isolates and revealed that 98% of them were MDR. PCR analysis using 25 selected isolates showed the predominance of metallo-β-lactamase gene bla_NDM (80%) and ESBL genes bla_OXA (48%) and bla_CTX-M-15 (32%). The AmpC gene was detected in 68% of the isolates, while 32% was tetC positive. Notably, 34% of the isolates were resistant to carbapenem. Whole genome sequence (WGS) analysis of an extensively drug-resistant (XDR) isolate (L16) revealed the presence of the notorious sequence type 131 responsible for multi-drug-resistant infections, multiple antibiotic resistance genes (ARGs), virulence genes, and mobile genetic elements that pose risks to environmental transmission. Our results indicate that MDR is alarmingly increasing in Bangladesh that critically limits the treatment option against infections and contributes to further aggravation to the prevailing situation of MDR worldwide. The findings of this study will be valuable in designing sustainable strategies to contain MDR in the region.

Epigallocatechin Gallate: The Emerging Wound Healing Potential of Multifunctional Biomaterials for Future Precision Medicine Treatment Strategies

Immediate treatment for cutaneous injuries is a realistic approach to improve the healing rate and minimise the risk of complications. Multifunctional biomaterials have been proven to be a potential strategy for chronic skin wound management, especially for future advancements in precision medicine. Hence, antioxidant incorporated biomaterials play a vital role in the new era of tissue engineering. A bibliographic investigation was conducted on articles focusing on in vitro, in vivo, and clinical studies that evaluate the effect and the antioxidants mechanism exerted by epigallocatechin gallate (EGCG) in wound healing and its ability to act as reactive oxygen species (ROS) scavengers. Over the years, EGCG has been proven to be a potent antioxidant efficient for wound healing purposes. Therefore, several novel studies were included in this article to shed light on EGCG incorporated biomaterials over five years of research. However, the related papers under this review's scope are limited in number. All the studies showed that biomaterials with scavenging ability have a great potential to combat chronic wounds and assist the wound healing process against oxidative damage. However, the promising concept has faced challenges extending beyond the trial phase, whereby the implementation of these biomaterials, when exposed to an oxidative stress environment, may disrupt cell proliferation and tissue regeneration after transplantation. Therefore, thorough research should be executed to ensure a successful therapy.

Antimicrobial Resistance Patterns in Diabetic Foot Infections, an Epidemiological Study in Northeastern Italy

This study is a retrospective epidemiological assessment of bacterial species isolated from a cohort of out-patients with diabetic foot infections referred to our “Diabetic Foot Unit” over one year, with particular attention to index pathogens, as identified by the EARS Network. Staphylococcus aureus and Pseudomonas aeruginosa accounted for 33.5% and 11.9% of cases, respectively. MRSA was isolated in 27.1% of patients, with 14.06% showing additional resistance to three antimicrobial classes. Pseudomonas aeruginosa presented extensive resistance to fluoroquinolones (57.3%), which was associated with resistance to piperacillin in 17.6% or to carbapenems in 23.5% of cases. Other pathogens, such as methicillin resistantStaphylococcus epidermidis, Escherichia coli and Morganella morganii ESBL and Enterococcus faecium VRE, were also found.

Hemostatic Electrospun Nanocomposite Containing Poly(lactic acid)/Halloysite Nanotube Functionalized by Poly(amidoamine) Dendrimer for Wound Healing Application: In Vitro and In Vivo Assays

The main challenge in treating injuries is excessive bleeding whereas intervention is required if the body's hemostatic systems fail to control the bleeding. Herein, a novel nanocomposite consisting of poly(lactic acid) (PLA) and poly(amidoamine) (PAMAM) dendrimer functionalized halloysite nanotube (HNT) with a highly porous structure via electrospinning is developed. HNT is functionalized by PAMAM via divergent synthetic routes from zero to third-generation numbers. The effect of different percentages and generation numbers of PAMAM dendrimer (G1, G2, and G3) functionalized HNT on PLA is studied using physicochemical nanocomposite characteristics. These resultant nanocomposites provide a nanofibrous structure with appropriate physicochemical characteristics such as mechanical properties, surface wettability, and water permeability. The hemostatic assays indicate that nanocomposite with PAMAM G3 functionalized HNT have the quickest blood clotting time due to the abundant amino functional group. Furthermore, the nanocomposites with 10 wt% of nanoparticles significantly promote cellular behavior in vitro. The in vivo study demonstrates that PLA/PAMAM G3 functionalized HNT promotes angiogenesis, collagen deposition, and re-epithelialization in the wound sites of the rat model, as well as inhibiting inflammatory response. The findings indicate that nanofibrous structure and the presence of dendrimer functionalized HNT have a synergetic effect on the enhanced nanocomposite wound healing performance.

3D-printed antioxidant antibacterial carboxymethyl cellulose/ε-polylysine hydrogel promoted skin wound repair

Developing a wound dressing for the treatment of large and irregular-shaped wounds remains a great challenge. Herein we developed novel printable bionic hydrogels with antibacterial and antioxidant properties which could effectively overcome the challenge by inhibiting inflammation and accelerating wound healing. The CMC/PL (CP) hydrogels were customized with glycidyl methacrylate (GMA) modified carboxymethyl cellulose (CMC) and ε-polylysine (ε-PL) via ultraviolet (UV) light polymerization using a 3D printer. Except for the high compression modulus (238 kPa), stable rheological properties, and effective degradability, these CP hydrogels also had an excellent inhibitory effect (95%) on both Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). Remarkably, CP hydrogels could remove the excessive reactive oxygen species (ROS) and protect the fibroblasts from damage. Compared with the commercial dressing (Tegaderm ™ film), CP hydrogels showed a better ability to increase the expression of VEGF and CD31, accelerate granulation tissue regeneration, and promote wound healing. This work provides a new strategy to fabricate on-demand multi-functional hydrogels in the field of skin tissue engineering.

Intelligent Nanoparticle-Based Dressings for Bacterial Wound Infections

Conventional wound dressing materials containing free antibiotics for bacterial wound infections are presented with several limitations, that is, lack of controlled and triggered release capabilities, and may often not be adequate to address the complex bacteria microenvironment of such infections. Additionally, the improper usage of antibiotics may also result in the emergence of drug resistant strains. While delivery systems (i.e., nanoparticles) that encapsulate antibiotics may potentially overcome some of these limitations, their therapeutic outcomes are still less than desirable. For example, premature drug release or unintended drug activation may occur, which would greatly reduce treatment efficacy. To address this, responsive nanoparticle-based antimicrobial therapies could be a promising strategy. Such nanoparticles can be functionalized to react to a single stimulus or multi stimulus within the bacteria microenvironment and subsequently elicit a therapeutic response. Such "intelligent" nanoparticles can be designed to respond to the microenvironment, that is, an acidic pH, the presence of specific enzymes, bacterial toxins, etc. or to an external stimulus, for example, light, thermal, etc. These responsive nanoparticles can be further incorporated into wound dressings to better promote wound healing. This review summarizes and highlights the recent progress on such intelligent nanoparticle-based dressings as potential wound dressings for bacteria-infected wounds, along with the current challenges and prospects for these technologies to be successfully translated into the clinic.

Novel chitosan-ulvan hydrogel reinforcement by cellulose nanocrystals with epidermal growth factor for enhanced wound healing: In vitro and in vivo analysis

Several dressing materials can be used efficiently in recent times, both in their natural and synthetic combinations like; microfibers, film, nanofibers, hydrogels, and various drugs. The specific characteristics, such as biocompatibility and providing a favorable environment for wound healing, make many polysaccharides pivotal as wound dressings. Keeping in view the importance of these polysaccharides, we have developed novel chitosan-ulvan hydrogel incorporated by cellulose nanocrystals (CNCs) loading epidermal growth factor (EGF) drug (CS-U-CNC-EGF) by the freeze-dried process. The morphological features of novel hydrogel were perceived by FTIR, XRD, FESEM, and DSC analysis. The incorporation of the nanocrystals content modified the porous microstructure at pore size from 237 ± 59 μm to 53 ± 16 μm, improved mechanical stress curve from 0.57 MPa to 1.2 MPa, thermal and swelling behavior. The novel nanocomposites revealed non-toxic behavior and excellent cell proliferation. Whereas hydrogel showed sustained release of the epidermal growth factor (EGF), thereby enhancing EGF delivery at the wound site for 15 days from a 100% wound contraction treated group. Moreover, the controlled release of EGF from CS-U-CNC-EGF hydrogels showed significantly faster-wound healing efficiency concerning considerably faster granulations tissue formation and collagen deposition. The study's results point to possible future applications of this composite hydrogel in wound healing as a wound dressing material.

Characterization of staphylococci sampled from diabetic foot ulcer of Jordanian patients

AIMS

The aim of this study was to isolate and characterize staphylococcal isolates from diabetic foot ulcers (DFU) in Jordanian patients.

METHODS AND RESULTS

Selected aerobic pathogens recovered from DFU specimens and patients' nares with a focus on staphylococci were investigated. Antimicrobial susceptibilities and the prevalence of methicillin-resistant staphylococci (MRS) were determined. SCCmec types and toxigenic characteristics were analysed and spa typing was performed for methicillin-resistant Staphylococcus aureus (MRSA) isolates. The relationship between toxigenic characteristics of MRSA and the Wagner ulcer grading system was statistically analysed. A total number of 87 DFU patients were recruited for the study. The DFU cultures were polymicrobial. Members of the genus Staphylococcus were the most common among DFU-associated isolates found in 48·3% (n = 42) of all patients enrolled. Coagulase-negative staphylococci (CoNS) comprised 63·3% of staphylococci isolated from DFUs predominated by Staphylococcus epidermidis in both DFU (7·6%) and nares (39·2%). Staphylococcus aureus was isolated from DFUs and nares in 14·2 and 9·8%, respectively, while 93 and 70% of these isolates were MRSA. Most of MRSA carried SCCmec type IV (76·2%) while SCCmec elements were non-typeable in most methicillin resistant coagulase negative staphylococci (MR-CoNS) (61·9%). The most frequent MRSA spa type was t386 (23·8%). Most MRSA and MR-CoNS exhibited resistance towards aminoglycosides, fluoroquinolones and macrolides and susceptibility towards vancomycin, mupirocin and linezolid. No association was found between the possession of pvl, tst, sea and hlg toxins and Wagner ulcer grading system (P value >0·05).

CONCLUSIONS

This analysis of Jordanian DFU culture demonstrated its polymicrobial nature with predominance of Staphylococcus sp.

SIGNIFICANCE AND IMPACT OF THE STUDY

This study is the first of its type to assess the microbiology of DFU among Jordanian patients. The results will help in the appropriate application of antimicrobial chemotherapy in the management of DFU.

Antimicrobial properties of olive oil phenolic compounds and their regenerative capacity towards fibroblast cells

Some micronutrients of vegetable origin are considered potentially useful as wound-healing agents because they can increase fibroblast proliferation and differentiation.

THE AIM OF THIS STUDY

was to evaluate the regenerative effects of selected olive oil phenolic compounds on cultured human fibroblasts and explore their antimicrobial properties.

MATERIAL AND METHODS

The CCD-1064Sk fibroblast line was treated for 24 h with 10^-6M luteolin, apigenin, ferulic, coumaric acid or caffeic acid, evaluating the effects on cell proliferation by using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) spectrophotometric assay; the migratory capacity by the scratch assay and determining the expression of Fibroblast Growth Factor (FGF), Vascular Endothelial Growth Factor (VEGF), Transforming Growth Factor- β1 (TGFβ1), Platelet Derived Growth Factor (PDGF), and Collagen Type I (COL-I) genes by real-time polymerase chain reaction. The antimicrobial capacity of the polyphenols was evaluated by the disc diffusion method.

RESULTS

All compounds except for ferulic acid significantly stimulated the proliferative capacity of fibroblasts, increasing their migration and their expression of the aforementioned genes. With respect to their antimicrobial properties, treatment with the studied compounds inhibited the growth of Staphylococcus aureus, Staphylococcus epidermidis, Escherichia coli, Proteus spp., and Candida Albicans.

CONCLUSIONS

The phenolic compounds in olive oil have a biostimulatory effect on the regeneration capacity, differentiation, and migration of fibroblasts and exert major antibacterial activity. According to the present findings, these compounds may have a strong therapeutic effect on wound recovery.

A thermostable Fe/Mn SOD of Geobacillus sp. PCH100 isolated from glacial soil of Indian trans-Himalaya exhibits activity in the presence of common inhibitors

Superoxide dismutases are the enzymes involved in dismutation of superoxide radicals into oxygen and hydrogen peroxide. The present work reports a thermostable Fe/Mn SOD of Geobacillus sp. strain PCH100 (GsSOD) isolated from glacial soil. Purified recombinant GsSOD is a dimeric protein of ~57 kDa that exhibited highest activity at a temperature of 10 °C and pH of 7.8. Maximum enzyme velocity and Michaelis constant of the GsSOD were 1098.90 units/mg and 0.62 μM, respectively. At 80 °C, thermal inactivation rate constant and half-life of GsSOD were 3.33 × 10^-3 min^-1 and 208 min, respectively. Interestingly, GsSOD tolerated a temperature of 100 °C and 130 °C up to 15 min and 5 min, respectively. Circular dichroism and differential scanning calorimetry confirmed thermostable nature of GsSOD. Apoenzyme of GsSOD regained enzymatic activity in the presence of Fe²⁺ and Mn²⁺ as metal ion cofactors. GsSOD was stable under varying concentrations of chemicals, namely ethylenediaminetetraacetic acid, potassium cyanide, hydrogen peroxide, chloroform-ethanol, 3-[(3-cholamidopropyl)-dimethylammonio]-1-propanesulfonate, Tween-20, Triton X-100, urea, and guanidine hydrochloride. The enzyme exhibited >70% activity in presence of 10 mM metal ions. Owing to its thermostable nature and resistance to chemical inhibitors, GsSOD is a potential enzyme for industrial applications.

Hemostatic and antibacterial PVA/Kaolin composite sponges loaded with penicillin-streptomycin for wound dressing applications

Hemorrhage is the major hindrance over the wound healing, which triggers microbial infections and might provoke traumatic death. Herein, new hemostatic and antibacterial PVA/Kaolin composite sponges were crosslinked using a freeze-thawing approach and boosted by penicillin–streptomycin (Pen-Strep). Physicochemical characteristics of developed membranes were analyzed adopting Fourier transformed infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), a thermal gravimetric analyzer (TGA), and differential scanning calorimetry (DSC). Furthermore, the impacts of kaolin concentrations on porosity, swelling behavior, gel fraction, and degradation of the membranes were investigated. SEM analyses revealed a spongy-like structure of hydrogels associated with high dispersion of kaolin inside PVA matrix. The thermal characteristics of PVA/Kaolin were significantly ameliorated compared to the prime PVA. Moreover, the results exhibited significant variations of swelling performance, surface roughness and pore capacity due to the alterations of kaolin contents. Besides, the adhesive strength ability was manifestly enhanced for PVA-K0.1 sponge. Biomedical evaluations including antibacterial activity, blood clotting index and thrombogenicity of the membranes were studied. The contact of PVA/Kaolin to blood revealed notable augmentation in blood clotting. Furthermore, the incorporation of kaolin into PVA presented mild diminution in antibacterial activities. Moreover, PVA/Kaolin composites illustrated no cellular toxicity towards fibroblast cells. These remarkable features substantiate that the PVA-K0.1 sponge could be applied as a multifunctional wound dressing.

Efficacy of hyperbaric oxygen therapy for diabetic foot ulcer, a systematic review and meta-analysis of controlled clinical trials

Studies have suggested that hyperbaric oxygen therapy (HBOT) is effective in the healing of diabetic foot ulcer (DFU); however, there is a lack of consensus. Therefore, to assess the efficacy of HBOT on diabetic foot ulcer among diabetic patients, controlled clinical trials were searched through PubMed, EMBASE, Clinical key, Ovid Discovery, ERMED, Clinical Trials.gov databases for randomized controlled trials (RCTs) and other sources until 15 September 2020. Studies that evaluated the effect of HBOT on diabetic foot ulcer, complete healing, amputation, adverse events, ulcer reduction area, and mortality rate were included. Of 1984 study records screened, 14 studies (768 participants) including twelve RCTs, and two CCTs were included as per inclusion criteria. The results with pooled analysis have shown that HBOT was significantly effective in complete healing of diabetic foot ulcer (OR = 0.29; 95% CI 0.14-0.61; I² = 62%) and reduction of major amputation (RR = 0.60; 95% CI 0.39-0.92; I² = 24%). Although, it was not effective for minor amputations (RR = 0.82; 95% CI 0.34-1.97; I² = 79%); however, less adverse events were reported in standard treatment group (RR = 1.68; 95% CI 1.07-2.65; I² = 0%). Nevertheless, reduction in mean percentage of ulcer area and mortality rate did not differ in HBOT and control groups. This review provides an evidence that hyperbaric oxygen therapy is effective as an adjunct treatment measure for the diabetes foot ulcers. These findings could be generalized cautiously by considering methodological flaws within all studies.

Negative pressure wound therapy in grade 1 and 2 diabetic foot ulcers: A randomized controlled study

BACKGROUND AND AIMS

Foot ulcers are one of the major causes of morbidity and mortality among diabetics in India. Early diagnosis and timely management is vital in preventing the progression of the disease which may require amputation. Conventional methods take a long time for healing. This study aims to compare negative pressure wound therapy (NPWT) and conventional saline dressings in diabetic foot ulcer (DFU) healing.

METHODS

This prospective randomized study was conducted in 45 patients with grade 1 and 2 DFUs. 22 patients in group A received NPWT and 23 patients in group B received saline dressings. The formation of granulation tissue, reduction in ulcer size, duration of hospital stay and time for complete healing of wounds were assessed.

RESULTS

The formation of granulation tissue (91.14 vs 52.61%, p < 0.001) and reduction in ulcer size (40.78 vs 21.18%, p = 0.008) at 14 days was significantly more in group A. The duration of hospital stay (15.68 vs 29.00 days, p < 0.001) and time for 100% coverage of the wound with granulation tissue (14.82 ± 7.30 vs 44.57 ± 7.11 days, p < 0.001) was significantly less in group A. Complete healing of wounds at 3 months was observed in 20 patients (90.9%) in group A and 6 patients (26.1%) in group B (p = 0.006).

CONCLUSION

In our study NPWT led to early reduction in ulcer size, more granulation tissue formation, shorter hospital stay and complete wound healing. In lower and middle income countries like India with high prevalence of DFUs, early recovery is a boon to the patients to resume their daily activities.

Bio-functional hydrogel membranes loaded with chitosan nanoparticles for accelerated wound healing

Wounds are often recalcitrant to traditional wound dressings and a bioactive and biodegradable wound dressing using hydrogel membranes can be a promising approach for wound healing applications. The present research aimed to design hydrogel membranes based on hyaluronic acid, pullulan and polyvinyl alcohol and loaded with chitosan based cefepime nanoparticles for potential use in cutaneous wound healing. The developed membranes were evaluated using dynamic light scattering, proton nuclear magnetic resonance, Fourier transform infrared spectroscopy, thermogravimetric analysis, and scanning electron microscopy. The results indicated the novel crosslinking and thermal stability of the fabricated hydrogel membrane. The in vitro analysis demonstrates that the developed membrane has water vapors transmission rate (WVTR) between 2000 and 2500 g/m²/day and oxygen permeability between 7 and 14 mg/L, which lies in the range of an ideal dressing. The swelling capacity and surface porosity to liberate encapsulated drug (cefepime) in a sustained manner and 88% of drug release was observed. The cefepime loaded hydrogel membrane demonstrated a higher zone of inhibition against Staphylococcus aureus, Pseudomonas aeruginosa, and Escherichia coli and excisional rat model exhibit expeditious recovery rate. The developed hydrogel membrane loaded with cefepime nanoparticles is a promising approach for topical application and has greater potential for an accelerated wound healing process.

Antioxidant and antibacterial polyelectrolyte wound dressing based on chitosan/hyaluronan/phosphatidylcholine dihydroquercetin

Antioxidant and antimicrobial wound dressings are the most favorable for acute and chronic wounds treatment. Herein, we formulated a multifunctional polyelectrolyte wound dressing membrane on the basis of chitosan (Ch) and hyaluronan (HA) enhanced by phosphatidylcholine dihydroquercetin (PCDQ). Physicochemical properties and microstructures of fabricated films were investigated adopting Fourier transform infrared (FT-IR) spectroscopy, thermogravimetric analysis (TGA) and scanning electron microscope (SEM). Furthermore, water uptakes, wettability profiles, surface roughness, and mechanical characteristics of the developed membranes were studied. The developed wound dressing revealed free radical scavenging potency, hemocompatibility with a tendency to enhance blood clotting. Furthermore, incorporation of PCDQ significantly promoted the antibacterial and anti-inflammatory activities of Ch/HA/PCDQ. Moreover, Ch/HA/PCDQ films exhibited cellular compatibility towards mouse fibroblast cells. The capability of Ch/HA/PCDQ to promote wound healing was evaluated using adult Wistar albino female rats. The in vivo findings demonstrated that Ch/HA/PCDQ films significantly ameliorated mouse full-thickness wounds as evidenced by a reduction in the wound area. Moreover, histological examinations of wounds dressed with Ch/HA/PCDQ illustrated a prominent re-epithelialization compared with wounds handled with the cotton gauze and Ch/HA dressings, exposing the efficiency of PCDQ. These findings emphasized that a Ch/HA/PCDQ membrane has outstanding potential for wound healing and skin regeneration.

Healthcare resources attributable to methicillin-resistant Staphylococcus aureus orthopedic surgical site infections

The number of orthopedic surgeries is increasing as populations steadily age, but surgical site infection (SSI) rates remain relatively consistent. This study aimed to quantify the healthcare resources attributable to methicillin-resistant Staphylococcus aureus (MRSA) SSIs in orthopedic surgical patients. The analysis was conducted using a national claims database comprising data from almost all Japanese residents. We examined patients who underwent any of the following surgeries between April 2012 and March 2018: amputation (AMP), spinal fusion (FUSN), open reduction of fracture (FX), hip prosthesis (HPRO), knee prosthesis (KPRO), and laminectomy (LAM). Propensity score matching was performed to identify non-SSI control patients, and generalized estimating equations were used to estimate the differences in outcomes between the case and control groups. The numbers of MRSA SSI cases (infection rates) ranged from 64 (0.03%) to 1,152 (2.33%). MRSA SSI-attributable increases in healthcare expenditure ranged from $11,630 ($21,151 vs. $9,521) for LAM to $35,693 ($50,122 vs. $14,429) for FX, and increases in hospital stay ranged from 40.6 days (59.2 vs. 18.6) for LAM to 89.5 days (122.0 vs. 32.5) for FX. In conclusion, MRSA SSIs contribute to substantial increases in healthcare resource utilization, emphasizing the need to implement effective infection prevention measures for orthopedic surgeries.

Microbial spectrum, antibiotic susceptibility profile, and biofilm formation of diabetic foot infections (2014-18): a retrospective multicenter analysis

This study identifies the risk factors, microbiological properties, antimicrobial susceptibility patterns, mortality, and clinical complications associated with organisms causing diabetic foot infections (DFIs) with or without antibiotic treatment using data from a retrospective multicenter surveillance. Specimens collected from different hospitals were cultured and the extended-spectrum β-lactamase (ESBL) excretion was estimated. The antibacterial susceptibility pattern and biofilm formation were completed along with the recommended standard methods. Overall, 792 diabetic foot patients (DFPs) were enrolled and a total of 1803 causative organisms were isolated. Polymicrobial infection was identified in 48.5% of the patients. The isolated Gram-positive pathogens (46.7%) were higher than Gram-negative (38.6%) or anaerobes (7.9%). The predominant pathogens were S. aureus (22.2%), methicillin-resistant S. aureus (7.7%), Enterococcus spp. (12.8%), Pseudomonas aeruginosa (9.4%), E. coli (7.9%), Klebsiella spp. (7.5%), Proteus mirabilis (8.9%), coagulase negative staphylococci (CoNS) (6.6%), anaerobic organisms (5.9%), and fungi (2.3%). Vancomycin and clindamycin exhibited no activity against Gram-positive bacteria. However, meropenem and imipenem displayed high activity against the Gram-negative isolates. Out of the 765 tested strains, 251 showed moderate (15.8%) to high (34%) level biofilm-producing phenotype. DFIs were widespread among the diabetic patients with different microbial etiology and the major organisms were aerobic organisms. Our findings may provide an insight into the development of appropriate therapeutic strategies for the management of DFIs.

Frequency and Antimicrobial Susceptibility Patterns of Diabetic Foot Infection of Patients from Bandar Abbas District, Southern Iran

Diabetic foot infection is among the most common complications of diabetes mellitus which significantly causes hospitalization and is the most prevalent etiology of nontraumatic amputation worldwide. The current study aimed at assessing the frequency and antimicrobial susceptibility patterns of diabetic foot infection of patients from the Bandar Abbas area, in the south of Iran. In this study, a total of 83 diabetic patients with diabetic infected foot wounds referring to Shahid Mohammadi Hospital, Bandar Abbas, from 2017 to 2018 were assessed. Samples were obtained from wound sites and evaluated by aerobic culture and also an antibiogram test for antibiotic susceptibility. Factors including age, sex, type of diabetes, the medication used for diabetes, previous history of diabetic foot infection, duration of wound incidence, fever, and laboratory indices were recorded for each subject. The most prevalent detected bacteria were Escherichia coli (20.5%), Enterococcus sp. (16.9%), Klebsiella sp. (12%), Staphylococcus aureus (8.4%), Enterobacter sp. (7.2%), and Acinetobacter sp. (6%). The results of antibiogram tests revealed the most and the least antibiotic sensitivity for E. coli sp. as meropenem and ciprofloxacin, for Enterococcus sp. as gentamicin and ciprofloxacin, for Klebsiella sp. as amikacin and cotrimoxazole, and for Enterobacter sp. as cotrimoxazole and both amikacin and ciprofloxacin. Staphylococcus aureus was sensitive to vancomycin and doxycycline, and Acinetobacter sp. was 100% resistant to all antibiotics except amikacin and gentamycin. A significant statistical association was found between the C-reactive protein and the patients' diabetic foot infection organisms (P=0.019). Findings of the study revealed E. coli sp. as the most common bacteria which are infecting the foot lesions in the studied population. The highest antibiotic susceptibility was seen for vancomycin, linezolid, and carbapenem.

The Novel Role of Healing from Bacterial Infections of Lower Limb Open Fractures by X-Ray Exposure

Objective

To confirm the role of X-ray exposure in treating infected wound fractures at the lower limb and determine X-ray exposure times.

Methods

Fifty-one wound swabs were collected from patients with infected open fractures at the lower limb with grade II, IIIA, B, and C according to the Gustilo and Anderson classification system and then cultured. The bacterial isolates were identified by biochemical tests and the VITEK-2 System and tested against several antibiotics. The X-ray exposure was done for open fractures by radiography (at kV133 and 5 milliambers).

Results

The higher isolation rate was recorded for Staphylococcus aureus with 21 (41.2%) isolates, and most of them (20, 95.2%) were isolated from grade II fractures. The isolation rate of Gram-negative bacteria was 25.5% for Escherichia coli with 13 isolates, 19.6% for Pseudomonas aeruginosa with 10 isolates, and 13.7% for Klebsiella pneumoniae with 7 isolates, most of which were isolated from grade III fractures. The isolation rate of P. aeruginosa was 60% (6 isolates) from grade IIIA and 71.4% (5 isolates) from grade IIIB for K. pneumoniae, while for E. coli it was 69.2% (9 isolates) from grade IIIC. All the bacterial isolates recorded high levels of antibiotic resistance against most tested antibiotics. Wound cultures of grade II fractures appeared sterile after the first X-ray exposure, and these wounds were infected with S. aureus or P. aeruginosa. However, cultures of grade IIIA and IIIB fractures appeared sterile after the second X-ray exposure for all isolated bacteria, except for S. aureus (grade IIIA fractures) (after the third X-ray exposure). Grade IIIC fractures showed sterile culture after the third X-ray exposure for wounds infected with P. aeruginosa and E. coli.

Conclusions

The study concluded that X-ray exposure showed high effectiveness in treating infected open fractures.

Prevalence and interrelationships of foot ulcer, risk-factors and antibiotic resistance in foot ulcers in diabetic populations: A systematic review and meta-analysis

BACKGROUND

Diabetic foot ulceration (DFU) is the prime health concern globally. It accounts for the major burden related to disease mortality and morbidity and economic cost. The timely and early recognition of the DFU can help present its occurrence and improve clinical outcomes.

AIM

To evaluate interrelationships between foot ulcers, risk factors, and antibiotic resistance among diabetic patients having ulcers in their foot.

METHODS

The databases such as PubMed, ERIC, Medline, and Google Scholar were extensively used for the extraction of studies. The selected studies were published within the time-period of 2014-2018. Ten studies were selected, which were found to be completely relevant to the current study.

RESULTS

The prevalence of diabetic foot ulcers among the population was evaluated, and the associated risk factors with its prevalence. Moreover, few studies also reported on the bacteria that are found to be most prevailing among diabetic patients. A narrative discussion was drawn through this analysis, which was used to highlight the specific area of research through selected studies, extraction of the significant information that matched with the topic of research, and analysis of problem through the findings of the selected articles. The results helped in assessing significant knowledge regarding the risk factors of diabetic foot ulcers and the role of antimicrobial resistant in its treatment.

CONCLUSION

The gram-negative bacteria were found to be the most common reason for diabetic foot ulcers. The study only included 10 studies that are not sufficient to produce generalized results, and no information was reported on the tests required to analyze antimicrobial susceptibility that can guide clinicians to propose better and sound treatment plans. It is evident that most study results depicted that the most common risk factors were found to be hypertension and neuropathy.

Bacterial nanocellulose from agro-industrial wastes: low-cost and enhanced production by Komagataeibacter saccharivorans MD1

Bacterial nanocellulose (BNC) has been drawing enormous attention because of its versatile properties. Herein, we shed light on the BNC production by a novel bacterial isolate (MD1) utilizing various agro-industrial wastes. Using 16S rRNA nucleotide sequences, the isolate was identified as Komagataeibacter saccharivorans MD1. For the first time, BNC synthesis by K. saccharivorans MD1 was investigated utilizing wastes of palm date, fig, and sugarcane molasses along with glucose on the Hestrin-Schramm (HS) medium as a control. After incubation for 168 h, the highest BNC yield was perceived on the molasses medium recording 3.9 g/L with an initial concentration of (v/v) 10%. The physicochemical characteristics of the BNC sheets were inspected adopting field-emission scanning electron microscope (FESEM), atomic force microscopy (AFM), X-ray diffraction (XRD), and Fourier transform infrared (FTIR) analysis. The FESEM characterization revealed no impact of the wastes on either fiber diameter or the branching scheme, whereas the AFM depicted a BNC film with minimal roughness was generated using date wastes. Furthermore, a high crystallinity index was estimated by XRD up to 94% for the date wastes-derived BNC, while the FTIR analyses exhibited very similar profiles for all BNC films. Additionally, mechanical characteristics and water holding capacity of the produced BNCs were studied. Our findings substantiated that expensive substrates could be exchanged by agro-industrial wastes for BNC production conserving its remarkable physical and microstructural properties.