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INTRODUCTION: Circulating tumor DNA (ctDNA) can be obtained from cell-free DNA (cfDNA) andis a new technique for genotyping, response assessment and prognosis in lymphoma. METHODS: Eighteen patients with samples at diagnosis (ctDNA1), after treatment (ctDNA2) and extracted from diagnostic tissue (FFPE) were evaluated. RESULTS: In all patients, at least one mutation in cfDNA was detected at diagnosis. CREBBP was the most frequent mutated gene (67 %). In 12 of the 15 patients with complete remission, the mutation attributed to the disease found at diagnosis cleared with treatment. A reduction in the ctDNA was observed after treatment in 14 patients, 12 of whom achieved complete remission. Correlations were found between the ctDNA at diagnosis and total metabolic tumor volume (r = 0.51; p-value = 0.014) and total lesion glycolysis 2.5 (r = 0.47; p-value = 0.024) by PET at diagnosis and between ctDNA at diagnosis and radiomic features of the lesions with the largest standardized uptake value. There was a strong inverse correlation between ΔctDNA1 and ΔSUVmax by PET/CT (r = -0.8788; p-value = 0.002). CONCLUSION: Analysis of ctDNA and PET/CT in large B-cell lymphoma are complementary data for evaluating tumor burden and tumor clearance after treatment. Analysis of radiomic data might help to identify tumor characteristics and their changes after treatment.

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Infective Endocarditis (IE) is a complex, life-threatening disease. The aim of the present study was to evaluate the impact of the Endocarditis-Team on management of IE. This observational study conducted at a university hospital (2015‒22), included adult patients with IE. The study period was divided in two periods: before (pre-Endocarditis-Team; pre-ET) and after the establishment of the Endocarditis-Team (post-Endocarditis-Team; post-ET) on January 2018. Among 505 IE episodes (187 in pre-Endocarditis-Team, 318 in post-ET period), 18F-Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography was more commonly used in post-ET period (14 % vs. 28 %; p < 0.001). Overall, thirty-day and one-year mortality were 14 % and 27 %, respectively; no difference was observed between the two periods. In post-ET period, the administration of 4-weeks, rather than 6-weeks, of intravenous antimicrobial treatment was higher than in the post-ET period (15 % vs. 45 %; p < 0.001). Indication for surgery was present in 115 (61 %) patients in pre-ET and in 153 (48 %) in the post-ET period. In post-ET period, among patients with indication, valve surgery was more frequently performed (66 % vs. 78 %; p = 0.038). Such difference was due to a higher acceptance of operative indication by the cardiac surgeon (69 % vs. 94 %; p = 0.013). The observed increase in number of patients benefiting from cardiac surgery in the post-ET period led to a decrease of subsequent embolic events, since among patients with operative indication (n = 268), new embolic events after the establishment of the indication were more common in the pre-ET period compared to post-ET (23 % vs. 12 %; p = 0.033). After the implementation of the multidisciplinary Endocarditis-Team we observed several improvements in the general management of IE patients.

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The differential diagnosis between malignant and benign adrenal cortical tumors is challenging, and concurrent androgen and cortisol production should raise  suspicion of a malignant tumor. We present the case of a 36-year-old woman who exhibited pronounced hirsutism, clitoromegaly, and secondary amenorrhea. A contrast-enhanced computed tomography (CT) scan revealed a 35 × 27 mm right adrenal mass with unenhanced CT attenuation of 40 Hounsfield units (HUs). The mass exhibited absolute and relative washout rates of 50% and 28%, respectively, and was accompanied by a 25 × 20 mm adenopathy located in the hepatogastric space. Total testosterone was elevated by 247 ng/dL (8.56 nmol/L) (normal reference range, 10-75 ng/dL; 0.34-2.6 nmol/L). A 1-mg dexamethasone suppression test revealed an elevated serum morning cortisol concentration of 10.57 µg/dL (291.58 nmol/L) (reference range, <1.8 µg/dL; < 49.66 nmol/L). A fluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) scan revealed increased uptake in both the adrenal mass and the adenopathy. Subsequently, the patient underwent an open right adrenalectomy and lymphadenectomy. Histological examination revealed the presence of an adrenal adenoma with myelolipomatous metaplasia, as well as a positive polymerase chain reaction (PCR) for Mycobacterium tuberculosis in the adenopathy.

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PURPOSE: This retrospective study was undertaken to assess the predictive efficacy of 18F-FDG PET/CT -derived radiomic features concerning the co-mutation status of epidermal growth factor receptor (EGFR) and TP53 in LUAD. METHODS: A cohort of 150 LUAD patients underwent pretreatment 18F-FDG PET/CT scans with known mutation status of EGFR and TP53 were collected. The feature extraction based on their PET/CT images utilized the Pyradiomics package based on the 3D Slicer. The optimal radiomic features were selected through correlation analysis and the Gradient Boosting Decision Tree (GBDT) algorithm, followed by the construction of the radiomic model. The clinical model incorporated meaningful clinical variables, whereas the complex model integrated both the radiomic and clinical models. The area under the receiver operating characteristic curve (AUC) facilitated the comparison of prediction performance across the three models. The DCA gauged the clinical utility of these models. RESULTS: The patient cohort was randomly allocated into a training set (n = 105) and a validation set (n = 45) in a 7:3 ratio. Eleven PET and eleven CT optimal radiomic features were selected to construct the radiomic model. The model showed a good ability to discriminate the co-occurrence of EGFR and TP53, with AUC equal to 0.850 in the training set, and 0.748 in the validation set, compared with 0.750 and 0.626 for the clinical model. The complex model exhibited the highest AUC values, with 0.880 and 0.794 in both sets, but there were no significant differences compared to the radiomic model. The DCA revealed favorable clinical value.

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Parkinsonian syndromes are considered clinicopathological conditions that are challenging to diagnose. Molecular imaging with [18F]-FDOPA and [18F]-FDG contributes to a more accurate clinical diagnosis by evaluating presynaptic dopaminergic pathways and glucose metabolism, respectively. The aim of this study was to correlate diagnoses made from dual PET/CT with the initial clinical diagnoses, as well as during follow-ups in patients with Parkinsonian syndromes. A secondary objective was to describe the imaging findings. Methods: A total of 150 patients with a clinical diagnosis of neurodegenerative Parkinsonism were evaluated using dual PET/CT. Clinically, 82% were diagnosed with PD, while the remaining 18% had an atypical Parkinsonism. Results: Using dual PET/CT, the most frequent diagnosis was PD in 67% of the patients, with the rest being diagnosed with an atypical Parkinsonism. In an agreement analysis between the initial clinical diagnosis and the imaging diagnosis by dual PET/CT, a concordance of 94.1% (n = 95) was observed for PD. In the remaining patients, the clinical diagnosis differed from that suggested by dual PET/CT, with atypical Parkinsonian syndromes being diagnosed as DLB in 40% (n = 4), PSP in 46.7% (n = 7), MSA-C in 75% (n = 6), MSA-P in 70% (n = 7), and CBD in 66.7% (n = 4). A total of 38.66% (n = 58) of patients were followed up (median follow-up of 27 months), with a Kappa coefficient of 0.591 (p < 0.001), suggesting substantial agreement. Conclusions: Dual FDOPA-FDG PET/CT demonstrated moderate agreement with the initial clinical diagnosis of Parkinsonism and moderate to substantial agreement during follow-up. This dual technique, therefore, stands out in differentiating between types of Parkinsonisms.

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OBJECTIVE: Image quality in positron emission tomography (PET) is influenced by positron range. In this work, the effect of the magnetic field of a PET/MR Siemens Biograph mMR 3T on the quality of PET images was studied. APPROACH: Experimental measurements were conducted using18F and68Ga-filled phantoms to quantify image uniformity, recovery coefficients (RCs), spill-over ratios and percent contrast for spherical lesions. Tissue-equivalent phantoms (lung inhale and exhale, adipose, water, trabecular and cortical bone) were used together with a line source to quantify the impact of the magnetic field on the reconstructed PET images. A comparative analysis was made with images obtained with a PET/CT Biograph Vision 600, using the same radionuclides and phantoms. MAIN RESULTS: Higher RCs values were obtained when the image quality phantom was filled with68Ga and scanned with the PET/MR system compared to those obtained with the PET/CT scanner. Hot spheres in the lesion detectability phantom, appear contracted in the transverse direction in the PET/MR system, an effect more evident for68Ga compared to18F, but no elongation in the direction parallel to the magnetic field was observed. In the PET/CT scanner, radial profiles taken from axial slices of line sources, show longer distribution tails extending beyond 20 mm when filled with68Ga and placed inside lung-inhale tissue. In the PET/MR scanner the radial profiles of all materials collapsed into a single distribution with tails extending no more than 10 mm in the direction perpendicular to the magnetic field. SIGNIFICANCE: Positron range depends on positron energy and material density in which they traverse. The results show an evident improvement in image quality in the transaxial direction only, particularly in phantoms filled with68Ga when using a PET/MR system as opposed to images acquired in the PET/CT system due to the presence of the magnetic field.

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Dienelactone hydrolase (DLH) is one of numerous hydrolytic enzymes with an α/ß-hydrolase fold, which catalyze the hydrolysis of dienelactone to maleylacetate. The DLHs share remarkably similar tertiary structures and a conserved arrangement of catalytic residues. This study presents the crystal structure and comprehensive functional characterization of a novel thermostable DLH from the bacterium Hydrogenobacter thermophilus (HtDLH). The crystal structure of the HtDLH, solved at a resolution of about 1.67 Å, exhibits a canonical α/ß-hydrolase fold formed by eight ß-sheet strands in the core, with one buried α-helix and six others exposed to the solvent. The structure also confirmed the conserved catalytic triad of DHLs formed by Cys121, Asp170, and His202 residues. The HtDLH forms stable homodimers in solution. Functional studies showed that HtDLH has the expected esterase activity over esters with short carbon chains, such as p-nitrophenyl acetate, reaching optimal activity at pH 7.5 and 70 °C. Furthermore, HtDLH maintains more than 50 % of its activity even after incubation at 90 °C for 16 h. Interestingly, HtDLH exhibits catalytic activity towards polyethylene terephthalate (PET) monomers, including bis-1,2-hydroxyethyl terephthalate (BHET) and 1-(2-hydroxyethyl) 4-methyl terephthalate, as well as other aliphatic and aromatic esters. These findings associated with the lack of activity on amorphous PET indicate that HtDLH has characteristic of a BHET-degrading enzyme. This work expands our understanding of enzyme families involved in PET degradation, providing novel insights for plastic biorecycling through protein engineering, which could lead to eco-friendly solutions to reduce the accumulation of plastic in landfills and natural environments.

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BACKGROUND: Efforts on a global scale for combating malaria have achieved substantial progress over the past twenty years. Two Central American nations have accomplished their goal of eliminating malaria: El Salvador and Belize. Honduras has decreased the incidence of malaria and now reports fewer than 4000 malaria cases annually, aspiring to reach elimination by 2030. To accomplish this goal, it is essential to assess the existing strategies employed for malaria control and to address the task of incorporating novel intervention strategies to identify asymptomatic reservoirs. METHODS: A survey for detecting asymptomatic cases was carried out in the community of Kaukira, in Gracias a Dios, Honduras, focusing on malaria transmission during 2023. Asymptomatic community members were recruited as participants, malaria screening was performed through a rapid diagnostic test in situ, and a blood sample was collected on filter paper. Highly sensitive molecular assays based on photo-induced electron transfer PCR (PET-PCR) were performed to detect the two species of Plasmodium circulating in Honduras: Plasmodium vivax and Plasmodium falciparum. In addition, the identification of the parasite species was verified by amplifying three genetic markers (Pvmsp3α, Pvmsp3ß, and Pfmsp1). RESULTS: A total of 138 participants were recruited, mostly adult women. All individuals tested negative on the rapid diagnostic test. Positive results for malaria were detected by PET-PCR in 17 samples (12.3%). Most samples (12 out of 17) were amplified with a Ct value between 37 and 42, indicating very low parasitemias. Out of the 17 samples, 16 of them also showed amplification in the species assays. There were nine cases of P. falciparum infections and seven cases of P. vivax infections that were further confirmed by nested PCR (nPCR) of Pvmsp3 and Pfmsp1. Parasitemias ranged from 100 p/µL to less than 0.25 p/µL. One sample showed mixed infection. CONCLUSIONS: The existence of asymptomatic malaria reservoirs in Honduras can contribute to disease transmission and pose a challenge that may hinder elimination efforts, requiring public health authorities to modify surveillance strategies to identify the disease and treat this population accordingly.

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BACKGROUND: Metastatic hormone-sensitive prostate cancer (mHSPC) is treatment-resistant and generally considered incurable. The development of prostate-specific membrane antigen positron emission-computed tomography (PSMA PET/CT) has generated immense expectations due to its diagnostic accuracy in prostate cancer (PCa). PSMA expression of the primary tumor, quantified by SUVmax, is a predictor of oncological outcomes. The role of PSMA-PET/CT SUVmax in metachronous mHSPC treated with ADT plus second-generation antiandrogens (ARSI) is unknown. The main aim of this study was to evaluate 68Ga-PSMA-11expression (SUVmax) as a potential prognostic biomarker in patients with metachronous mHSPC treated with ADT and first or second-generation antiandrogens. A second aim was to determine the association between PSMA SUVmax and PSA response to hormone therapy. MATERIAL AND METHODS: Patients diagnosed with metachronous mHSPC between July 2017 and February 2023 who developed biochemical recurrence following radical surgery (with or without salvage radiotherapy and/or ADT) or external radiation therapy (with or without ADT) were included. All patients underwent 68 Ga-PSMA-11 PET/CT imaging and the SUVmax value was determined for all measurable locations. The SUVmax value was used for the semiquantitative analysis. The Wilcoxon method was used to compare responders (PSA reduction ≥ 50%) to non-responders (PSA reduction < 50%). The SUVmax value and hormone therapy were evaluated as independent variables relative to the PSA response rate or PSA reduction using the linear regression method. A mixed-effects model (ANOVA) was used for the comparisons. RESULTS: A total of 82 patients were included. Median follow-up was 11.7 months. On the linear regression analysis, patients with a high SUVmax treated with ADT + ARSI showed a greater PSA response (p = 0.034) than those treated with ADT + first-generation antiandrogens. In the mixed-effects model, SUVmax was significant (p = 0.041). On the univariate analysis, PSA at recurrence (HR, 3.2; 95% CI: 1.07-13.6; p = 0.078) and the number of metastases (HR, 4.77; 95% CI 1.1-26.1: p = 0.002) were associated with the type of hormone therapy administered. CONCLUSIONS: PSMA-PET/CT SUVmax is a prognostic biomarker that can be used to predict a PSA response to ADT + ARSI in patients with metachronous mHSPC. However, these findings need to be confirmed in larger prospective studies.

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Actinomycosis is a rare infectious disease characterized by slowly progressive, chronic suppurative lesions, often mistaken for malignancies due to its ability to mimic them. It is caused by Actinomyces bacteria, which are part of the normal flora of the human oropharynx, gastrointestinal, and urogenital tracts. This case report describes a 51-year-old male with a history of mandibular rhabdomyosarcoma presenting with severe shoulder and hip pain, dysphagia, and headaches, initially suspected to be a cancer recurrence. However, after further investigation, including a PET-CT and tonsillectomy, the diagnosis of actinomycosis was confirmed through histopathological examination. The case highlights the diagnostic challenges of actinomycosis, especially in patients with complex clinical histories, emphasizing the importance of considering it as a differential diagnosis in similar presentations. The patient was treated with long-term antibiotic therapy, predominantly beta-lactams, demonstrating the necessity of a comprehensive diagnostic approach and the implications of a delayed diagnosis. This case underscores the critical need for high clinical suspicion and awareness among healthcare professionals regarding the potential for actinomycosis to mimic more common diseases, ensuring timely and accurate treatment.

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PURPOSE: The objective of this investigation is to explore the capability of baseline 18F-FDG PET/CT radiomics to predict the prognosis of diffuse large B-cell lymphoma (DLBCL) with extranodal involvement (ENI). METHODS: 126 patients diagnosed with DLBCL with ENI were included in the cohort. The least absolute shrinkage and selection operator (LASSO) Cox regression was utilized to refine the optimum subset from the 1328 features. Cox regression analyses were employed to discern significant clinical variables and conventional PET parameters, which were then employed with radiomics score to develop combined model for predicting both progression-free survival (PFS) and overall survival (OS). The fitness and the predictive capability of the models were assessed via the Akaike information criterion (AIC) and concordance index (C-index). RESULTS: 62 patients experienced disease recurrence or progression and 28 patients ultimately died. The combined model exhibited a lower AIC value compared to the radiomics model and SDmax/clinical variables for both PFS (507.101 vs. 510.658 vs. 525.506) and OS (215.667 vs. 230.556 vs. 219.313), respectively. The C-indices of the combined model, radiomics model, and SDmax/clinical variables were 0.724, 0.704, and 0.615 for PFS, and 0.842, 0.744, and 0.792 for OS, respectively. Kaplan--Meier curves showed significantly higher rates of relapse and mortality among patients classified as high-risk compared to those classified as low-risk (all P < 0.05). CONCLUSIONS: The combined model of clinical variables, conventional PET parameters, and baseline PET/CT radiomics features demonstrates a higher accuracy in predicting the prognosis of DLBCL with ENI.

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The development of new radiopharmaceuticals for the detection of hidden infection foci has great relevance for early detection and the selection of the correct treatment, particularly in immunosuppressed patients. In that sense, the labelling of antimicrobial peptides (AMPs) that are capable of binding specifically to the pathogenic microorganism which causes the infection, should provide a sufficiently specific agent, able to distinguish an infection from a sterile inflammation. Defensins are particularly interesting molecules with antimicrobial activity, the EcgDf1 defensin was identified from the genome of a Uruguayan native plant, Erythrina crista-galli, the 'Ceibo' tree. Our group has previously reported a synthetic biologically active short analogue EcgDf21 (ERFTGGHCRGFRRRCFCTKHC) successfully labelled with 99mTc. Herein we present a shorter analogue which also preserves the γ-core domain, as a pharmacophore for a potential infection detection agent. This peptide was derivatized with the bifunctional chelating agent 1,4,7-triazacyclononane-1,4,7-triacetic acid (NOTA) through a lysine linker in the amino-terminal group (NOTA-KGHCRGFRRRC) and radiolabelled with 68Ga ([68Ga]Ga-NOTA-K-EcgDf1(10)). The [68Ga]Ga-NOTA-K-EcgDf1(10) labelling procedure rendered a product with high radiochemical purity and stability in the labelling milieu. The Log P value indicated that the complex has a hydrophilic behaviour, confirmed by the biodistribution profile. The [68Ga]Ga-NOTA-K-EcgDf1(10) complex demonstrated specific binding to cultures of Candida albicans and Aspergillus niger. Its biodistribution showed renal elimination and low accumulation in the rest of the body. It was possible to successfully differentiate sterile inflammation from infection by PET images in nude mice with a target/non-target ratio of 3.3 for C. albicans and 3.7 for A. niger, respectively.

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Collisions lesions are rare neoplasms where two histologically distinct tumors coexist in the same organ or anatomical site. Vertebral hemangiomas (VHs) are the most common lesions involving the vertebral bodies and imaging findings of typical and atypical hemangiomas, variant forms of hemangioma such as aggressive hemangiomas are well known, but collision lesions involving VHs are extremely rare. This article presents a case report of a 73-year-old male patient diagnosed with clear cell renal cancer in a rare presentation of a bone metastasis coinciding with the same anatomical position as a VH (collision lesion). This required a multidisciplinary approach involving various diagnostic techniques to determine the best therapeutic management.

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Introduction: This study aimed to perform a cross-cultural adaptation of the cat-owner/dog-owner relationship scales. The method involved several stages: conceptual, item, semantic, operational, measurement, and functional equivalence. Procedures included translation, synthesis of translations, back-translation, consensus on the English versions, external evaluation by the original authors, expert committee evaluation, and pre-tests. Methods: The study surveyed 234 pet owners across Brazil using a 20-item questionnaire. Data analysis utilized confirmatory factor analysis, covariance-based modeling, and multigroup analysis. Results: The study confirmed the content and construct validity of the model, demonstrating good convergent validity. Hypotheses testing revealed significant inverse relationships between Perceived Cost and Perceived Emotional Closeness, and between Perceived Cost and Pet-Owner Interactions. A positive correlation was found between Perceived Emotional Closeness and Pet-Owner Interactions, with Perceived Emotional Closeness also mediating the relationship between Perceived Cost and Pet-Owner Interactions. No significant differences were found across different pet owner groups, indicating the scale's invariance and reliability across various demographics. Discussion: The study significantly expands understanding of the complex dynamics in pet-owner relationships and emphasizes the interplay between emotional and practical factors. It offers valuable insights for future research and practices in animal and human welfare.

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Dirofilaria immitis infection is routinely detected in dogs during veterinary care in tropical and subtropical regions worldwide. Parasitological tests for the detection of this infection are routinely performed only in areas with a high prevalence. Baixada Fluminense, a region in Rio de Janeiro, was considered heartworm-free until local veterinarians began to receive blood exams results indicating the presence of microfilariae (MF). A laboratory database was hence used to collect data from 2017 to 2020 to understand the extent of spread of the parasite in this area. The results of complete blood count analysis and MF or heartworm antigen detection tests conducted on canine samples sent from veterinary clinics in Baixada Fluminense (Magé, Duque de Caxias, Guapimirim, Nova Iguaçu, and São João de Meriti municipalities) were included. In total, the results of 16,314 hematological tests were considered. The overall prevalence of D. immitis was 3.4% (554/16,314), considering that only one test result was obtained per animal on the same day. This study is highly relevant because it indicates the spreading geographic distribution of the worms, heightens awareness among local health professionals and the general population, and encourages compliance with prophylactic measures to prevent further spread of parasite.

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A new, sustainable polypropylene terephthalate (PPT) coating was synthesized from recycled polyethylene terephthalate (PET) and applied onto a hydraulic concrete substrate to improve its durability. For the first step, PET bottle wastes were ground and depolymerized by glycolysis using propylene glycol (PG) in a vessel-type reactor (20-180 °C) to synthesize bis(2-hydroxypropyl)-terephthalate (BHPT), which was applied as a coating to one to three layers of hydraulic concrete substrate using the brushing technique and polymerized (150 °C for 15 h) to obtain PPT. PET, BHPT, and PPT were characterized by FT-IR, PET, and PPT using TGA, and the PPT coatings by SEM (thickness), ASTM-D3359-17 (adhesion), and water contact angle (wettability). The durability of hydraulic concrete coated with PPT was studied using resist chloride ion penetration (ASTM-C1202-17), carbonation depth at 28 days (RILEM-CPC-18), and the absorption water ratio (ASTM-C1585-20). The results demonstrated that the BHPT and PPT were synthetized (FT-IR), and PPT had a similar thermal behavior to PET (TGA); the PPT coatings had good adhesion to the substrate, with thicknesses of micrometric units. PPT coatings presented hydrophilic hydrophilic behavior like PET coatings, and the durability of hydraulic concrete coated with PPT (2-3 layers) improved (migration of chloride ions decreased, carbonation depth was negligible, and the absorption water ratio decreased).

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The overwhelming use of PET plastic in various day-to-day activities led to the voluminous increase in PET waste and growing environmental hazards. A plethora of methods have been used that are associated with secondary pollutants. Therefore, microbial degradation of PET provides a sustainable approach due to its versatile metabolic diversity and capacity. The present work highlights the cutinase enzyme's role in PET degradation. This study focuses on the bacterial cutinases homologs screened from 43 reported phylum of bacteria. The reported bacterial cutinases for plastic degradation have been chosen as reference sequences, and 917 sequences have shown homology across the bacterial phyla. The dienelactone hydrolase (DLH) domain was identified for attaining specificity towards PET binding in 196 of 917 sequences. Various computational tools have been used for the physicochemical characterization of 196 sequences. The analysis revealed that most selected sequences are hydrophilic, extracellular, and thermally stable. Based on this analysis, 17 sequences have been further pursued for three-dimensional structure prediction and validation. The molecular docking studies of 17 selected sequences revealed efficient PET binding with the three sequences derived from the phylum Bacteroidota, the lowest binding energy of -5.9 kcal/mol, Armatimonadota, and Nitrososphaerota with -5.8 kcal/mol. The two enzyme sequences retrieved from the phylum Bacteroidota and Armatimonadota are metagenomically derived. Therefore, the present studies concluded that there is a high probability of finding cutinase homologs in various environmental resources that can be further explored for PET degradation.

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Objectives: Bisphosphonates (BFs) show clinical effectiveness in managing osteoporosis and bone metastases but pose risks of bisphosphonate-related jaw osteonecrosis (BRONJ). With no established gold standard for BRONJ treatment, our focus is on symptom severity reduction. We aimed to assess the preventive effects of bioactive glass and/or pericardial membrane in a preclinical BRONJ model, evaluating their potential to prevent osteonecrosis and bone loss post-tooth extractions in zoledronic acid (ZA)-treated animals. Methods: Rats, receiving ZA or saline biweekly for four weeks, underwent 1st and 2nd lower left molar extractions. Pericardial membrane alone or with F18 bioglass was applied post-extractions. Microarchitecture analysis and bone loss assessment utilized computerized microtomography (CT) and positron emission tomography (PET) with 18F-FDG and 18F-NaF tracers. Histological analysis evaluated bone injury. Results: Exclusive alveolar bone loss occurred post-extraction in the continuous ZA group, inducing osteonecrosis, osteolysis, osteomyelitis, and abscess formation. Concurrent pericardial membrane with F18 bioglass application prevented these outcomes. Baseline PET/CT scans showed no discernible uptake differences, but post-extraction 18F-FDG tracer imaging revealed heightened glucose metabolism at the extraction site in the ZA-treated group with membrane, contrasting the control group. Conclusion: These findings suggest pericardial membrane with F18 bioglass effectively prevents BRONJ in the preclinical model.