Palladium(II) Metal Complex Fabricated Titanium Implant Mitigates Dual-Species Biofilms in Artificial Synovial Fluid.

Metallodrugs have a potent application in various medical fields. In the current study, we used a novel Palladium(II) thiazolinyl picolinamide complex that was directly fabricated over the titanium implant to examine its potency in inhibiting dual-species biofilms and exopolysaccharides. Additionally, inhibition of mono- and dual-species biofilms by coated titanium plates in an in vitro joint microcosm was performed. The study was carried out for 7 days by cultivating mono- and dual-species biofilms on titanium plates placed in both growth media and artificial synovial fluid (ASF). By qPCR analysis, the interaction of co-cultured biofilms in ASF and the alteration in gene expression of co-cultured biofilms were studied. Remarkable alleviation of biofilm accumulation and EPS secretion was observed on the coated titanium plates. The effective impairment of biofilms and EPS matrix of biofilms on Pd(II)-E-coated titanium plates were visualized by Scanning Electron Microscopy. Moreover, coated titanium plates improved the adhesion of osteoblast cells, which is crucial for a bone biomaterial. The potential bioactivity of coated plates was also confirmed at the molecular level using qPCR analysis. The stability of coated plates in ASF for 7 days was examined with FESEM-EDAX analysis. Collectively, the present study provided an excellent anti-infective effect on Pd(II)-E-coated titanium plates without affecting their biocompatibility with bone cells.

Bioprospecting of aqueous phase from pyrolysis of plant waste residues to disrupt MRSA biofilms.

Methicillin resistant Staphylococcus aureus (MRSA) infections have increased at an alarming rate, recently. In India, stubble burning and air pollution due to the burning of agricultural and forest residues have also increased over the past decade causing environmental and health hazards. This work evaluates the anti-biofilm property of the aqueous phase obtained from pyrolysis of wheat straw (WS AQ) and pine cone (PC AQ) against an MRSA isolate. The WS AQ and PC AQ compositions were determined by GC-MS analysis. The minimum inhibitory concentration was found to be 8% (v v-1) and 5% (v v-1) for WS AQ and PC AQ, respectively. The eradication of biofilms was performed on hospital contact surfaces namely, stainless steel and polypropylene and found to be 51% and 52% for WS AQ and PC AQ, respectively. Compounds identified from the aqueous phase of WS and PC docked against AgrA protein showed good binding scores.

Transition metal complex laminated bioactive implant alleviates Methicillin Resistant Staphylococcus aureus virulence.

Orthopedic implant infections cause a serious threat after implantation. The major source of implant infection is biofilms which are highly tolerant to antibiotics due to the presence of rigid biofilm matrix. Hence to overcome biofilm mediated implant infections, we developed a novel antibiofilm agent, palladium (II) thiazolinyl picolinamide complex (Pd(II)-E). From our study, it was found that Pd(II)-E have profound biofilm inhibition activity and also reduced various virulence factors of Methicillin resistant Staphylococcus aureus (MRSA) including slime synthesis, Phenol soluble modulin (PSM) mediated spreading, Exopolysaccharides production and staphyloxanthin synthesis. Further, Pd(II)-E was coated over the titanium plates which was confirmed using EDX (Energy Dispersive X-Ray) analysis. The Pd(II)-E coated plates were able to prevent the biofilm formation on them which was evident under a Scanning electron microscope (SEM) and several virulent genes were found to be downregulated in the biofilms on the coated titanium plates which confirmed by qPCR. From our findings, it was found that Pd(II)-E coated titanium implants would be an effective alternate approach for preventing biofilm mediated implant infections.

Exploration of 3D Printing of Anti-Infective Urinary Catheters: Materials and Approaches to Combat Catheter-Associated Urinary Tract Infections (CAUTIs) - A Review.

Three-dimensional (3D) printing is a pioneering technology that has gained increased popularity in the fields of tissue engineering, drug design, drug delivery systems and biomedical devices. Thus, it enables us to explore this technique for fabricating 3D-printed catheters. Owing to its enhanced productivity and cost-efficiency, this technique can be utilized to fabricate any material for manufacturing or designing catheters with antimicrobial properties. From 1930s, Foley's catheter had been widely used to drain the urinary bladder of patients with impaired bladder function. Despite the complications like catheter-associated urinary tract infections (CAUTIs), kidney damage, chronic infections, encrustations and personal discomfort during inflation of the balloon, Foley's catheter was used universally without any changes in product design. Currently, marketed catheters have been reported for reducing CAUTI, but the prevention of limitations by coating drugs onto the catheter is very expensive. Altering the physical properties of the catheter by biopolymer blend might ease the discomfort. Thus, new technologies have to be adopted to manufacture ideal catheters that are biocompatible and provide antimicrobial and anti-fouling properties. Herein, we provide an overview of 3D printing techniques along with different materials opted for manufacturing catheters to overcome the existing challenges and limitations.

Phytolectin nanoconjugates in combination with standard antifungals curb multi-species biofilms and virulence of vulvovaginal candidiasis (VVC) causing Candida albicans and non-albicans Candida.

Vulvovaginal candidiasis (VVC) is a commonly occurring yeast infection caused by Candida species in women. Among Candida species, C. albicans is the predominant member that causes vaginal candidiasis followed by Candida glabrata. Biofilm formation by Candida albicans on the vaginal mucosal tissue leads to VVC infection and is one of the factors for a commensal organism to get into virulent form leading to disease. In addition to that, morphological switching from yeast to hyphal form increases the risk of pathogenesis as it aids in tissue invasion. In this study, jacalin, a phytolectin complexed copper sulfide nanoparticles (NPs) have been explored to eradicate the mono and mixed species biofilms formed by fluconazole-resistant C. albicans and C. glabrata isolated from VVC patients. NPs along with standard antifungals like micafungin and amphotericin B have been evaluated to explore interaction behavior and we observed synergistic interactions between them. Microscopic techniques like light microscopy, phase contrast microscopy, scanning electron microscopy, confocal laser scanning microscopy were used to visualize the inhibition of biofilm by NPs and in synergistic combinations with standard antifungals. Real-time PCR analysis was carried out to study the expression pattern of the highly virulent genes which are responsible for yeast to hyphal switch, drug resistance and biofilm formation upon treatment with NPs in combination with standard antifungals. The current study shows that lectin-conjugated NPs with standard antifungals might be a different means to disrupt the mixed species population of Candida spp. that causes VVC. LAY SUMMARY: The present study focuses on exploiting the high biding affinity between the cell surface glycans present in Candida cells and the plant lectin, Jacalin. Jacalin serves as a 'Trojan Horse' wherein the lectin-coupled nanoparticles show a high efficacy when compared with the unconjugated nanoparticles. The present approach also improves the anti-biofilm activity of the antifungal drugs against drug-resistant Candida strains.

Heteroleptic pincer palladium(II) complex coated orthopedic implants impede the AbaI/AbaR quorum sensing system and biofilm development by Acinetobacter baumannii.

Implant-associated infections mediated by Acinetobacter baumannii biofilms have become a major concern in the healthcare sector. As biofilm formation by this important pathogen is mediated by quorum sensing, quorum sensing inhibitors (QSI) have gained much attention. The present study confirms that novel thiazolinyl-picolinamide based palladium(II) complexes had good biofilm disruptive and QSI properties against A. baumannii. Key QS-mediated virulence factors like pili mediated surface motility and polysaccharide production were inhibited by the best Pd(II) complex (E). This also showed potent inhibitory activity against both the standard and clinical strains of A. baumannii. Molecular docking analysis also proved the potent binding affinity of Pd(II)-E with the virulence targets. The Pd(II) complex also disrupted preformed biofilms and down-regulated the expression of QS mediated virulence genes in the biofilms established on implant material (titanium plates). As a whole, the present study showed that the novel thiazolinyl-picolinamide based Pd(II) complexes offer a promising anti-infective strategy to combat biofilm-mediated implant infections.

Biofilm-forming fluconazole-resistant Candida auris causing vulvovaginal candidiasis in an immunocompetent patient: A case report

Rationale: Candida auris is a potential emerging pathogen among Candida and causes serious health threats globally. Patient concerns: We reported a case of vulvovaginal candidiasis caused by Candida auris. A 26-year-old female presented with complaints of vaginal discharge, itching and low back pain. Diagnosis: High vaginal swab culture yielded Candida. The strain was confirmed as Candida auris by amplification and sequencing the internal transcribed spacer region. Antifungal susceptibility testing revealed that the isolate was resistant to fluconazole, amphotericin B and clotrimazole and susceptible to ketoconazole and nystatin. The isolate also exhibited biofilm forming ability. Interventions: Her symptoms did not subside with initial management with fluconazole and clotrimazole. Later, she was started on ketoconazole therapy. The patient responded well to ketoconazole. Outcome and lessons: To the best of our knowledge, this is the first report about the presence of a drug resistant biofilm forming Candida auris strain isolated from a vaginal swab sample from Chennai area. Biofilm forming ability might contribute to its drug resistance. Nucleic acid analysis helps in rapid and accurate identification of such rare species.

Essential oil based nanoemulsions to improve the microbial quality of minimally processed fruits and vegetables: A review.

Due to the convenience and nutritional value, minimally processed fruits and vegetables (MPFV) are one of the rapid growing sectors in the food industry. However, their microbiological safety is a cause of great concern. Essential oils (EOs), known for potent antimicrobial efficacy have been shown to reduce microbial load in MPFV, but their low water solubility, high volatility and strong organoleptic properties limit their wide use. Encapsulating EOs to nanoemulsion offers a viable remedy for such limitations. Due to the unique properties of the EOs nanoemulsion, there has been an increasing interest in their fabrication and use in food system. The present review article encompasses the overview of the prominent microflora present in MPFV, the recent developments on the fabrication and stability of EOs based nanoemulsion, their in vitro antimicrobial activity and their application in MPFV. This review also discusses the EOs based nanoemulsions antimicrobial mechanism of action and their regulatory issues related to their use. Application of EOs based nanoemulsion either as washing disinfectant or with incorporation into edible coatings have been shown to considerably improve the microbial quality and safety of MPFV. This efficacy has been further shown to increase when combined with other hurdles. However, further studies are required on the toxicity of EOs based nanoemulsion to assure its commercial exploitation.

Eilatimonas milleporae gen. nov., sp. nov., a marine bacterium isolated from the hydrocoral Millepora dichotoma.

A marine bacterial strain, designated MD2(T), was isolated from the damaged tissue of a hydrocoral, Millepora dichotoma, collected from the coral reef in the northern Red Sea, Gulf of Eilat, Israel. Strain MD2(T) was Gram-reaction-negative, rod-shaped and motile, and formed small, creamy and opaque colonies, 1-2 mm in diameter, after 3 days incubation on Marine agar at 30°C. The novel strain grew well in nutrient broth at 1.5-6 % NaCl and at 20-37°C. The major cellular fatty acids were iso-C17 : 1ω9c, iso-C17 : 0, C18 : 1ω7c and C17 : 1ω6c. The polar lipids consisted of phosphatidylglycerol, phosphatidylethanolamine, an unidentified lipid, two unidentified phospholipids, two unidentified glycolipids and two unidentified aminolipids. Ubiquinone Q-10 was the only respiratory lipoquinone. The DNA G+C content was 60.3 mol%. Analysis of the 16S rRNA gene sequence placed the organism in the α-subclass of the Proteobacteria with a sequence divergence of about 9 % from any species with a validly published name. The highest 16S rRNA gene sequence similarity (approximately 91 %) was notably with type strains of members of the genus Kordiimonas, Kordiimonas aestuarii 101-1(T), Kordiimonas lacus S3-22(T) and Kordiimonas gwangyangensis GW14-5(T). On the basis of genotypic, chemotaxonomic and phenotypic distinctness, strain MD2(T) represents a novel species in a new genus of the class Alphaproteobacteria, for which the name Eilatimonas milleporae gen. nov., sp. nov. is proposed. The type strain of the type species is MD2(T) ( = LMG 26586(T) = DSM 25217(T)).

Bacterial consortium of Millepora dichotoma exhibiting unusual multifocal lesion event in the Gulf of Eilat, Red Sea.

Colonies of the hydrocoral Millepora dichotoma along the Gulf of Eilat are exhibiting unusual tissue lesions in the form of white spots. The emergence and rapid establishment of these multifocal tissue lesions was the first of its kind reported in this region. A characterization of this morphological anomaly revealed bleached tissues with a significant presence of bacteria in the tissue lesion area. To ascertain possible differences in microbial biota between the lesion area and non-affected tissues, we characterized the bacterial diversity in the two areas of these hydrocorals. Both culture-independent (molecular) and culture-dependent assays showed a shift in bacterial community structure between the healthy and affected tissues. Several 16S rRNA gene sequences retrieved from the affected tissues matched sequences of bacterial clones belonging to Alphaproteobacteria and Bacteroidetes members previously associated with various diseases in scleractinian corals.