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BACKGROUND: The BODY-Q is a widely used patient-reported outcome measure for comprehensive assessment of treatment outcomes specific to patients undergoing body contouring surgery (BCS). However, for BODY-Q to be meaningfully interpreted and used in clinical practice, minimal important difference (MID) scores are needed. A MID is defined as the smallest change in outcome measure score that patients perceive important. OBJECTIVES: The aim of this study was to determine BODY-Q MID estimates for patients undergoing BCS to enhance the interpretability of the BODY-Q. METHODS: Data from an international, prospective cohort from Denmark, Finland, Germany, Italy, the Netherlands, and Poland were included. Two distribution-based methods were used to estimate MID: 0.2 standard deviations of mean baseline scores and the mean standardized response change of BODY-Q scores from baseline to 3 years postoperatively. RESULTS: A total of 12,554 assessments from 3,237 participants (mean age; 42.5±9.3 years; body mass index; 28.9±4.9 kg/m2) were included. Baseline MID scores ranged from 1 to 5 in the health-related quality of life (HRQL) scales and 3 to 6 in the appearance scales. The estimated MID scores from baseline to 3 years follow-up ranged from 4 to 5 in HRQL and from 4 to 8 in the appearance scales. CONCLUSIONS: The BODY-Q MID estimates from before BCS to 3 years postoperatively ranged from 4 to 8 and are recommended for use to interpret patients' BODY-Q scores, evaluate treatment effects of different BCS procedures, and for calculating sample size for future studies.

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Purpose: To assess management and outcomes of bladder neck stenosis (BNS) post-transurethral resection of the prostate (TURP) in 12 centers. Patients and Methods: A retrospective analysis of patients who underwent transurethral BN incision for stenosis following TURP from January 2015 and January 2023 was performed. Inclusion criteria included endoscopic diagnosis of BNS associated with obstruction and/or lower urinary tract symptoms. Data are presented as median and interquartile range. Two distinct univariable logistic regression analyses were performed to identify factors associated with overall urinary incontinence and recurrent stenosis. Results: Three hundred and seventy-two men were included. 95.2% of patients developed BNS following bipolar TURP. 21.0% of patients were on an indwelling catheter before BNS incision. Bipolar electrocautery was the most commonly employed energy for incision (66.5%). Collings knife was the most commonly employed (61.2%) instrument for incision, followed by end-firing holmium lasering (35.3%). Median operation time was 30 (25-45) minutes. The overall complication rate was 12.4%, with 19 (5.1%) patients suffering from acute urinary retention, 6 (1.6%) patients requiring prolonged irrigation due to persistent hematuria, and a surgical hemostasis was necessary in 8 cases (2.2%). Overall postoperative incontinence rate was 17.2%, with urge incontinence accounting for the most common type (45.3%). Incontinence lasted more than 3 months in 9/46 (14.3%) patients. Recurrent BNS occurred in 29 (7.8%) patients and was managed by re-endoscopic incision in 21 (5.6%) patients and dilatation only in 6 (1.6%) patients. Two (0.5%) patients underwent urethroplasty for recalcitrant stenosis. Logistic regression analysis showed that Collings knife was associated with higher odds of having postoperative incontinence (OR 3.93 95% CI 1.45-11.13, p=0.008) and BN recurrence (OR 3.589 95% CI 1.157-15.7, p=0.047). Conclusion: Transurethral BN incision provides satisfactory short-term results with an acceptable rate of complications.

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OBJECTIVE: To examine health-related quality of life (HRQL) and satisfaction with appearance in patients who have undergone bariatric surgery (BS) with or without subsequent body contouring surgery (BCS) in relation to the general population normative for the BODY-Q. BACKGROUND: The long-term impact of BS with or without BCS has not been established using rigorously developed and validated patient-reported outcome measures. The BODY-Q is a patient-reported outcome measure developed to measure changes in HRQL and satisfaction with appearance in patients with BS and BCS. METHODS: Prospective BODY-Q data were collected from 6 European countries (Denmark, the Netherlands, Finland, Germany, Italy, and Poland) from June 2015 to February 2022 in a cohort of patients who underwent BS. Mixed-effects regression models were used to analyze changes in HRQL and appearance over time between patients who did and did not receive BCS and to examine the impact of patient-level covariates on outcomes. RESULTS: This study included 24,604 assessments from 5620 patients. BS initially led to improved HRQL and appearance scores throughout the first postbariatric year, followed by a gradual decrease. Patients who underwent subsequent BCS after BS experienced a sustained improvement in HRQL and appearance or remained relatively stable for up to 10 years postoperatively. CONCLUSIONS: Patients who underwent BCS maintained an improvement in HRQL and satisfaction with appearance in contrast to patients who only underwent BS, who reported a decline in scores 1 to 2 years postoperatively. Our results emphasize the pivotal role that BCS plays in the completion of the weight loss trajectory.

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Acinetobacter baumannii is currently a serious threat to human health, especially to people with immunodeficiency as well as patients with prolonged hospital stays and those undergoing invasive medical procedures. The ever-increasing percentage of strains characterized by multidrug resistance to widely used antibiotics and their ability to form biofilms make it difficult to fight infections with traditional antibiotic therapy. In view of the above, phage therapy seems to be extremely attractive. Therefore, phages with good storage stability are recommended for therapeutic purposes. In this work, we present the results of studies on the stability of 12 phages specific for A. baumannii under different conditions (including temperature, different pH values, commercially available disinfectants, essential oils, and surfactants) and in the urine of patients with urinary tract infections (UTIs). Based on our long-term stability studies, the most optimal storage method for the A. baumannii phage turned out to be - 70 °C. In contrast, 60 °C caused a significant decrease in phage activity after 1 h of incubation. The tested phages were the most stable at a pH from 7.0 to 9.0, with the most inactivating pH being strongly acidic. Interestingly, ethanol-based disinfectants caused a significant decrease in phage titers even after 30 s of incubation. Moreover, copper and silver nanoparticle solutions also caused a decrease in phage titers (which was statistically significant, except for the Acba_3 phage incubated in silver solution), but to a much lesser extent than disinfectants. However, bacteriophages incubated for 24 h in essential oils (cinnamon and eucalyptus) can be considered stable.

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Bacteriolytic enzymes are promising antibacterial agents, but they can cause a typical immune response in vivo. In this study, we used a targeted modification method for two antibacterial endolysins, Pal and Cpl-1. We identified the key immunogenic amino acids, and designed and tested new, bacteriolytic variants with altered immunogenicity. One new variant of Pal (257-259 MKS → TFG) demonstrated decreased immunogenicity while a similar mutant (257-259 MKS → TFK) demonstrated increased immunogenicity. A third variant (280-282 DKP → GGA) demonstrated significantly increased antibacterial activity and it was not cross-neutralized by antibodies induced by the wild-type enzyme. We propose this variant as a new engineered endolysin with increased antibacterial activity that is capable of escaping cross-neutralization by antibodies induced by wild-type Pal. We show that efficient antibacterial enzymes that avoid cross-neutralization by IgG can be developed by epitope scanning, in silico design, and substitutions of identified key amino acids with a high rate of success. Importantly, this universal approach can be applied to many proteins beyond endolysins and has the potential for design of numerous biological drugs.

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Rothia is an opportunistic pathogen, particularly life-threatening for the immunocompromised. It is associated with pneumonia, endocarditis, peritonitis and many other serious infections, including septicemia. Of note, Rothia mucilaginousa produces metabolites that support and increase overgrowth of Pseudomonas aeruginosa, one of the ESKAPE bacteria. Endolysins are considered as antibacterial enzymes derived from bacteriophages that selectively and efficiently kill susceptible bacteria without harming human cells or the normal microbiome. Here, we applied a computational analysis of metagenomic sequencing data of the gastric mucosa phageome extracted from human patients' stomach biopsies. A selected candidate anti-Rothia sequence was produced in an expression system, purified and confirmed as a Rothia mucilaginosa- and Rothia dentocariosa-specific endolysin PolaR, able to destroy bacterial cells even when aggregated, as in a biofilm. PolaR had no cytotoxic or antiproliferative effects on mammalian cells. PolaR is the first described endolysin selectively targeting Rothia species, with a high potential to combat infections caused by Rothia mucilaginosa and Rothia dentocariosa, and possibly other bacterial groups. PolaR is the first antibacterial enzyme selected from the gastric mucosa phageome, which underlines the biological complexity and probably underestimated biological role of the phageome in the human gastric mucosa.

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Infections with the opportunistic Gram-negative bacterium Acinetobacter baumannii pose a serious threat today, which is aggravated by the growing problem of multi-drug resistance among bacteria, caused by the overuse of antibiotics. Treatment of infections caused by antibiotic-resistant A. baumannii strains with the use of phage therapy is not only a promising alternative, but sometimes the only option. Therefore, phages specific for clinical multi-drug resistant A. baumannii were searched for in environmental, municipal, and hospital wastewater samples collected from different locations in Poland. The conducted research allowed us to determine the biological properties and morphology of the tested phages. As a result of our research, 12 phages specific for A. baumannii, 11 of which turned out to be temperate and only one lytic, were isolated. Their lytic spectra ranged from 11 to 75%. The plaques formed by most phages were small and transparent, while one of them formed relatively large plaques with a clearly marked 'halo' effect. Based on Transmission Electron Microscopy (TEM), most of our phages have been classified as siphoviruses (only one phage was classified as a podovirus). All phages have icosahedral capsid symmetry, and 11 of them have a long tail. Optimal multiplicity of infections (MOIs) and the adsorption rate were also determined. MOI values varied depending on the phage-from 0.001 to 10. Based on similarities to known bacteriophages, our A. baumannii-specific phages have been proposed to belong to the Beijerinckvirinae and Junivirinae subfamilies. This study provides an additional tool in the fight against this important pathogen and may boost the interest in phage therapy as an alternative and supplement to the current antibiotics.

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Multiple pathogens are competing against the human immune response, leading to outbreaks that are increasingly difficult to control. For example, the SARS-CoV-2 virus continually evolves, giving rise to new variants. The ability to evade the immune system is a crucial factor contributing to the spread of these variants within the human population. With the continuous emergence of new variants, it is challenging to comprehend all the possible combinations of previous infections, various vaccination types, and potential exposure to new variants in an individual patient. Rather than conducting variant-to-variant comparisons, an efficient approach could involve identifying key protein regions associated with the immune evasion of existing immunity against the virus. In this study, we propose a new biotechnological application of bacteriophages, the phage display platform for experimental identification of regions (linear epitopes) that may function as cross-reacting IgG hotspots in SARS-CoV-2 structural proteins. A total of 34,949 epitopes derived from genomes of all SARS-CoV-2 variants deposited prior to our library design were tested in a single assay. Cross-reacting IgG hotspots are protein regions frequently recognized by cross-reacting antibodies in many variants. The assay facilitated the one-step identification of immunogenic regions of proteins that effectively induced specific IgG in SARS-CoV-2-infected patients. We identified four regions demonstrating both significant immunogenicity and the activity of a cross-reacting IgG hotspot in protein S (located at NTD, RBD, HR1, and HR2/TM domains) and two such regions in protein N (at 197-280 and 358-419 aa positions). This novel method for identifying cross-reacting IgG hotspots holds promise for informing vaccine design and serological diagnostics for COVID-19 and other infectious diseases.

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Endolysins are bacteriolytic enzymes derived from bacteriophages. They represent an alternative to antibiotics, since they are not susceptible to conventional antimicrobial resistance mechanisms. Since non-human proteins are efficient inducers of specific immune responses, including the IgG response or the development of an allergic response mediated by IgE, we evaluated the general immunogenicity of the highly active antibacterial enzyme, PlyC, in a human population and in a mouse model. The study includes the identification of molecular epitopes of PlyC. The overall assessment of potential hypersensitivity to this protein and PlyC-specific IgE testing was also conducted in mice. PlyC induced efficient IgG production in mice, and the molecular analysis revealed that PlyC-specific IgG interacted with four immunogenic regions identified within the PlyCA subunit. In humans, approximately 10% of the population demonstrated IgG reactivity to the PlyCB subunit only, which is attributed to cross-reactions since this was a naïve serum. Of note, in spite of being immunogenic, PlyC induced a normal immune response, without hypersensitivity, since both the animals challenged with PlyC and in the human population PlyC-specific IgE was not detected.

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Presented herein are the results of a novel recycling method for waste Tetra Pak® packaging materials. The polyethylene (PE-T) component of this packaging material, obtained via a separation process using a "solvents method", was used as a carbon source for the biosynthesis of polyhydroxyalkanoates (PHAs) by the bacterial strain Cupriavidus necator H16. Bacteria were grown for 48-72 h, at 30 °C, in TSB (nitrogen-rich) or BSM (nitrogen-limited) media supplemented with PE-T. Growth was monitored by viable counting. It was demonstrated that C. necator utilised PE-T in both growth media, but was only able to accumulate 40% w/w PHA in TSB supplemented with PE-T. Only 1.5% w/w PHA was accumulated in the TSB control, and no PHA was detected in the BSM control. Extracted biopolymers were characterised by nuclear magnetic resonance (NMR), Fourier-transform infrared (FTIR) spectroscopy, electrospray tandem mass spectrometry (ESI-MS/MS), gel permeation chromatography (GPC), and accelerator mass spectrometry (AMS). The characterisation of PHA by ESI-MS/MS revealed that PHA produced by C. necator in TSB supplemented with PE-T contained 3-hydroxybutyrate, 3-hydroxyvalerate, and 3-hydroxyhexanoate co-monomeric units. AMS analysis also confirmed the presence of 96.73% modern carbon and 3.27% old carbon in PHA derived from Tetra Pak®. Thus, this study demonstrates the feasibility of our proposed recycling method for waste Tetra Pak® packaging materials, alongside its potential for producing value-added PHA, and the ability of 14C analysis in validating this bioconversion process.

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Herein, an alternative method for adipic acid (AA) synthesis of industrial importance has been reported. The proposed novel method involves the one-step, solvent-free oxidation of a cyclohexane/cyclohexanone (CH/CH=O) mixture, with a cheap oxidizing agent such as O2 or air under mild conditions in the presence of N-hydroxyphtalimide (NHPI) and transition metals as catalysts. It has been showed that CH/CH=O mixture under applied mild conditions oxidized faster than CH and CH=O separately. This was due to the greater oxidizability of CH=O compared to CH. The peroxyl radicals formed by CH=O oxidation initiated the oxidation of the less reactive CH. Additionally, CH=O increased the polarity of the reaction mixture, promoting the solubility of NHPI. The influence of type and amount of catalyst, cyclohexane to cyclohexanone ratio, temperature, time, type of oxidizing agent on the composition of CH/CH=O oxidation products have been reported.

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While endometriosis affects up to 15% of the female population of childbearing potential, the involvement of the urinary system is a relatively rare occurrence. It affects only 1-2% of all patients with endometriosis. Symptoms consistent with chronic pelvic pain syndrome or dysuria, related to endometriosis, remain a challenge in both diagnostic and therapeutic terms. AIM: The aim of the study was to evaluate the long term effects of advanced laparoscopic surgery of deep infiltrating endometriosis of the bladder. MATERIALS AND METHODS: This paper is a summary of radical laparoscopic surgery results in 21 patients with urinary bladder endometriosis. The majority of cases involved primary endometriosis of the bladder, there was only one case of postoperative bladder endometriosis, that was diagnosed many years after a caesarean section. All patients underwent radical laparoscopic surgery. RESULTS: All endometriotic lesions involving the bladder wall were excised within healthy tissue margins in all patients undergoing surgery. Pathology confirmed endometriosis in all cases. Dysuria and chronic pelvic pain have completely withdrawn in all patients, and postoperative observation at the time of writing (median period of 30.7 months, range 4.1-111.2 months) revealed a consistent and durable therapeutic effect of surgery. CONCLUSIONS: Endometriosis of the urinary bladder is not a common pathology. Nevertheless, it should be taken into consideration in cases of unexplained dysuria or imaging suggestive of urinary bladder malignancy. The treatment of choice is radical laparoscopic excision of the endometriotic lesions. This modality usually ensures complete resolution of symptoms, along with a marginal risk for recurrence and minimal early and late complication rates.

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This study investigated the molecular structure of the polyhydroxyalkanoate (PHA) produced via a microbiological shake flask experiment utilizing oxidized polypropylene (PP) waste as an additional carbon source. The bacterial strain Cupriavidus necator H16 was selected as it is non-pathogenic, genetically stable, robust, and one of the best known producers of PHA. Making use of PHA oligomers, formed by controlled moderate-temperature degradation induced by carboxylate moieties, by examination of both the parent and fragmentation ions, the ESI-MS/MS analysis revealed the 3-hydroxybutyrate and randomly distributed 3-hydroxyvalerate as well as 3-hydroxyhexanoate repeat units. Thus, the bioconversion of PP solid waste to a value-added product such as PHA tert-polymer was demonstrated.

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Endometriosis affects 10-15% of the female population of childbearing potential. Endometrioid lesions of the cervical surface are a rare manifestation of the disease. There are various complaints related to this particular form of endometriosis, making the diagnosis challenging. Treatment also raises problems, as widely available and used therapeutic methods often prove to be ineffective. AIM: The aim of the study was to evaluate the efficacy of CO2 laser beam ablation in a group of patients with cervical endometriosis lesions. MATERIALS AND METHODS: This paper presents a summary of cervical endometriosis treatment efficacy in a group of 15 patients who have undergone CO2 laser ablation between May 2016 and April 2019. The majority of patients have already been treated for cervical endometriosis, using cryotherapy, electrocoagulation, curettage and loop electrosurgical excision procedure (LEEP). All patients, following preliminary colposcopy verification and exclusion of malignancies, have undergone CO2 laser ablation of endometrioid cervical lesions. A visual evaluation of the cervix was performed before treatment, directly after the procedure, as well as 4-6 weeks after the procedure, and subsequently every 6-8 months. RESULTS: This paper presents a summary of cervical endometriosis treatment efficacy in a group of 15 patients who have undergone CO2 laser ablation between May 2016 and April 2019. The majority of patients have already been treated for cervical endometriosis, using cryotherapy, electrocoagulation, curettage and loop electrosurgical excision procedure (LEEP). All patients, following preliminary colposcopy verification and exclusion of malignancies, have undergone CO2 laser ablation of endometrioid cervical lesions. A visual evaluation of the cervix was performed before treatment, directly after the procedure, as well as 4-6 weeks after the procedure, and subsequently every 6-8 months. CONCLUSIONS: Cervical endometriosis is a rare manifestation of the diseases, with variable symptoms. It can become a diagnostic challenge, as endometrioid lesions may be confused with cervical malignancies, as well as a therapeutic one, as many of the methods employed prove unsuccessful. Laser ablation of endometrioid cervical lesions seen to be a minimally invasive, safe and effective treatment method that can be offered in an outpatient setting.

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Endometriosis affects 6%-15% of the female population of childbearing potential. Endometriosis has a wide range of symptoms. Infertility is one of the major and common consequences of endometriosis. Many treatment options are offered to the infertile patient - pharmacotherapy, dietary treatment, Assisted Reproductive Technology (ART), and surgery. Medical and dietary treatment alleviate symptoms, without improvement in pregnancy rates. Limited value of surgery is sometimes advocated, suggesting only ART improve pregnancy rates. AIM: The aim of the study was to analyze the effectiveness of the surgical treatment of patients with endometriosis and infertility expressed in the number of pregnancies and the births. MATERIALS AND METHODS: The basis for the analysis was the prospectively updated database of patients with endometriosis undergoing surgical treatment, which included 768 records as of May 30, 2019. The analysis selected the period from 01/01/2013 to 31/12/2016, which treated 164 patients with endometriosis and sterility. 139 patients were qualified for the analysis. Most of the previously analyzed were treated for endometriosis and infertility (pharmacotherapy, surgery, ART-Assisted Reproductive Technology). All patients underwent standardized surgical treatment developed by the authors - radical conservative laparoscopic surgery. The analysis of pregnancies was performed for all patients jointly and according to the division according to the severity of the disease, including the methods of pregnancy (spontaneous pregnancy, ART). The analyzed group was divided according to the stage of endometriosis (IV - 40.3%, III - 21.6%, II - 26.6%, I - 11.5%), the majority being patients with symptoms of severe endometriosis (III + IV = 61.9%). Values of nominal variables were compared between groups with the chi-square test, and the Kruskal-Wallis test was used for measurable variables. As a statistical significance threshold, p <0.05 was accepted. RESULTS: By May 2019, a total of 130 pregnancies in 101 cases were registered. There were 35 abortions, 95 live births (including 7 premature births) and 2 ongoing pregnancies. The percentage of pregnancies in the study group was 72.66%. CONCLUSIONS: Pregnancy rate of 72.66% in the whole group and 70.93% in the group of advanced endometriosis is an encouraging and indicative result of radical conservative laparoscopic surgical treatment of endometriosis in patients with infertility.

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Polybutylene succinate (PBS) nanocomposite materials were prepared using a melt compounding process. The Mg2Al-based PBS nanocomposites, dispersed with inorganic-organic hybrid materials (layered double hydroxides, LDHs), were functionalized with the amino acids L-histidine (HIS) and L-phenylalanine (PHE). The rheological and anti-ultraviolet (anti-UV) properties were investigated and compared to filler-free PBS as well as LDH Mg2Al/nitrate as references. Both organo-modified LDHs exhibited a remarkable chain-extension effect for PBS with an outstanding increase in the zero-shear viscosity η0 for PBS-Mg2Al/PHE (two order of magnitude increase as compared to filler-free PBS). These results were compared to data found in the literature. Moreover, HIS and PHE anions embedded into the LDH structure can successfully prevent the chain scission reactions that usually occur during photo-ageing of PBS under UV radiation exposure. This highlights the outstanding performance of the LDH hybrid materials, and in particular, their application as a polymer chain extender and UV stabilizer for PBS, which can likely be extended to other biodegradable polymers.

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Orotic acid is a natural heterocyclic compound that acts as a nucleation agent in poly(lactic acid) (PLA). PLA materials with increasing orotic acid content were prepared and characterized. It was found that crystallinity of about 28% was reached with 0.3% content of the agent. Further enhancement in the content of the agent did not provoke any additional significant increase of crystallinity. Subsequently, it was investigated whether the orotic acid content affected photodegradation of PLA and, in the next phase, its biodegradation. The results of rheological measurements showed that the compound slightly accelerates photodegradation of the material, which was accompanied by the cleavage of PLA chains. Previous photodegradation was shown to accelerate the subsequent biodegradation by shortening the lag phase of the process, where the explanation is probably in the reduction of the polymer molecular weight during the photodegradation. Moreover, the presence of orotic acid in both initial and photodegraded samples was found to influence biodegradation positively by shortening the lag phase and increasing the observed maximal rate of the biodegradation.

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Nanocomposites based on poly(butylene succinate) (PBS) and hydrotalcite-type anionic clays (HTs) organo-modified with biomolecules characterized by antibacterial and/or antioxidant activities, such as l-ascorbic acid (ASA), phloretic acid (HPP), l-tyrosine (TYR) and l-tryptophan (TRP), have been prepared by in situ polymerization. From XRD analysis and rheology experiments in a molten polymer state, intercalated HT hybrid platelets acting here as a hybrid filler are found to be well dispersed into polymers while providing a chain extension effect on PBS. Moreover, the molecules, when hosted within a HT interlayer gap, do preserve their pristine antibacterial activity, both in HT and in the resulting PBS composites. In particular, under the experimental conditions tested, HT/ASA and HT/TYR present the best combination of both properties (chain extension effect and antibacterial), especially versus E. coli as high as 90 and 97% of inhibition, respectively, using 2.5 wt% hybrid filler only. These findings open future applications for PBS associated with the hybrid HT filler as multifunctional materials in active packaging applications.

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Excessive levels of plastic waste in our oceans and landfills indicate that there is an abundance of potential carbon sources with huge economic value being neglected. These waste plastics, through biological fermentation, could offer alternatives to traditional petrol-based plastics. Polyhydroxyalkanoates (PHAs) are a group of plastics produced by some strains of bacteria that could be part of a new generation of polyester materials that are biodegradable, biocompatible, and, most importantly, non-toxic if discarded. This study introduces the use of prodegraded high impact and general polystyrene (PS0). Polystyrene is commonly used in disposable cutlery, CD cases, trays, and packaging. Despite these applications, some forms of polystyrene PS remain financially and environmentally expensive to send to landfills. The prodegraded PS0 waste plastics used were broken down at varied high temperatures while exposed to ozone. These variables produced PS flakes (PS1⁻3) and a powder (PS4) with individual acid numbers. Consequently, after fermentation, different PHAs and amounts of biomass were produced. The bacterial strain, Cupriavidus necator H16, was selected for this study due to its well-documented genetic profile, stability, robustness, and ability to produce PHAs at relatively low temperatures. The accumulation of PHAs varied from 39% for prodegraded PS0 in nitrogen rich media to 48% (w/w) of dry biomass with the treated PS. The polymers extracted from biomass were analyzed using nuclear magnetic resonance (NMR) and electrospray ionization tandem mass spectrometry (ESI-MS/MS) to assess their molecular structure and properties. In conclusion, the PS0⁻3 specimens were shown to be the most promising carbon sources for PHA biosynthesis; with 3-hydroxybutyrate and up to 12 mol % of 3-hydroxyvalerate and 3-hydroxyhexanoate co-monomeric units generated.

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We report on the ability of bacteria to produce biodegradable polyhydroxyalkanoates (PHA) using oxidized polyethylene wax (O-PEW) as a novel carbon source. The O-PEW was obtained in a process that used air or oxygen as an oxidizing agent. R. eutropha H16 was grown for 48 h in either tryptone soya broth (TSB) or basal salts medium (BSM) supplemented with O-PEW and monitored by viable counting. Study revealed that biomass and PHA production was higher in TSB supplemented with O-PEW compared with TSB only. The biopolymers obtained were preliminary characterized by nuclear magnetic resonance (NMR), gel permeation chromatography (GPC), differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA). The detailed structural evaluation at the molecular level was performed by electrospray ionization tandem mass spectrometry (ESI-MS/MS). The study revealed that, when TSB was supplemented with O-PEW, bacteria produced PHA which contained 3-hydroxybutyrate and up to 3 mol % of 3-hydroxyvalerate and 3-hydroxyhexanoate co-monomeric units. The ESI-MS/MS enabled the PHA characterization when the content of 3-hydroxybutyrate was high and the appearance of other PHA repeating units was very low.