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This study investigates the synthesis and characterization of KSrVO4 phosphors doped with Er3+ ions using combustion synthesis route by using urea as a fuel. X-ray diffraction analysis confirmed the orthorhombic phase and nano-scale crystallite size of around 21 nm, while transmission electron microscopy showed spherical and rod-shaped morphologies. The studies detected upconversion emission spectra at 526, 542 and 643 nm, representing green and red transitions under 980 nm excitation. Downshifting emissions under 350 nm excitation revealed peaks at 492, 544 and 680 nm. The critical quenching concentration was 2.5 mol%, resulting from dipole-quadrupole interactions among dopant ions. The direct and indirect optical band gaps were calculated as 3.61 and 3.41 eV, respectively. The calculated chromaticity coordinates and color correlated temperature values of the phosphor surpassed 5000 K, suggesting its viability for cool LED applications. These findings emphasize KSrVO4:Er3+ as a promising greenish component in white LEDs and a potent upconverting luminescence material for bio-imaging and photovoltaics.
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Reducing defects in the active layer is important for improving the crystalline quality of all-inorganic perovskite solar cells (PSCs). Exploring novel additives is one of the most promising approaches to minimize active layer defects. In this work, two-dimensional (2D) SnSe nanosheets with excellent optoelectronic properties are prepared using an ultrasonic exfoliation method. The prepared 2D SnSe nanosheets are introduced into a CsPbI2Br precursor, which reduces the defect formation at grain boundaries and enhances the crystallinity of CsPbI2Br perovskites. We use the in situ photoluminescence (PL) technique to investigate the role of 2D materials in the crystallization process. The results show that SnSe nanosheets primarily shorten the grain boundary merging time and reduce the defect generation during the grain boundary merging stage, thereby regulating the crystallization of perovskite. In addition, SnSe nanosheets passivate uncoordinated Pb atoms at grain boundaries by Se atoms, further reducing the defect density in perovskite. As a result, PSCs exhibit a higher power conversion efficiency (PCE) of 14.24% and a Voc of 1.22 V. This study highlights the role of 2D materials in enhancing the crystalline quality and PCE of PSCs.
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Alginate is one of the most important marine colloidal polysaccharides, and its oligosaccharides have been proven to possess diverse biological functions. Alginate lyases could specifically degrade alginate and therefore serve as desirable tools for the research and development of alginate. In this report, a novel catalytic domain, which demonstrated no significant sequence similarity with all previously defined functional domains, was verified to exhibit a random endo-acting lyase activity to alginate. The action pattern analysis revealed that the heterologously expressed protein, named Aly44A, preferred to degrade polyM. Its minimum substrates and the minimum products were identified as unsaturated alginate trisaccharides and disaccharides, respectively. Based on the sequence novelty of Aly44A and its homologs, a new polysaccharide lyase family (PL44) was proposed. The discovery of the novel enzyme and polysaccharide lyase family provided a new entrance for the gene-mining and acquiring of alginate lyases, and would facilitate to the utilization of alginate and its oligosaccharides.
Subject(s)
Alginates , Polysaccharide-Lyases , Polysaccharide-Lyases/metabolism , Polysaccharide-Lyases/chemistry , Polysaccharide-Lyases/genetics , Alginates/chemistry , Alginates/metabolism , Substrate Specificity , Catalytic Domain , Oligosaccharides/chemistry , Oligosaccharides/metabolism , Amino Acid Sequence , Hexuronic Acids/chemistry , Hexuronic Acids/metabolismABSTRACT
Key Clinical Message: Acute digital ischemia is a rare manifestation of anti-synthetase syndrome in the absence of Raynaud's phenomenon. A high index of suspicion may result in early diagnosis and better clinical outcomes. Abstract: A 61-year-old male patient was admitted to the hospital for worsening arthralgias with morning stiffness lasting hours, as well as left sided headaches, and jaw pain while eating. He had significant weight loss and subjective fever at home. Multiple fingers and toes were noted to be ischemic. His laboratory workup was pertinent for significantly elevated inflammatory markers, and mild Creatinine kinase elevation. Chest imaging and later lung biopsy were notable for organizing pneumonia. Conventional angiogram showed evidence of significant digital disease without collaterals. Subsequent autoimmune screening tests with extended myositis-specific and myositis-associated panels revealed a strongly positive anti-PL-12 antibody and moderately positive anti- SSA-52KD IgG ab. After ruling out infectious etiologies and malignancy, anti-synthetase syndrome (ASyS) diagnosis was considered in the presence of ischemic digits, organizing pneumonia, polyarthralgia, constitutional symptoms, increased inflammatory markers and positive antibodies. The patient was treated with high dose prednisone and mycophenolate mofetil along with amlodipine and sildenafil for digital vasodilation. Acute digital ischemia may be the first manifestation of ASyS with ILD. A high index of suspicion is warranted for early diagnosis and better outcomes.
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We report the results of synthesis of zinc selenide (ZnSe) nanocrystals into SiO2/Si track templates formed by irradiation with 200 MeV Xe ions up to a fluence of 107 ions/cm2. Zinc selenide nanocrystals were obtained by chemical deposition from the alkaline aqueous solution. Scanning electron microscopy, X-ray diffractometry, Raman and photoluminescence spectroscopy, and electrical measurements were used for characterization of synthesized ZnSe/SiO2nanoporous/Si nanocomposites. XRD data for as-deposited precipitates revealed the formation of ZnSe nanocrystals with cubic crystal structure, spatial syngony F-43m (216). According to non-empirical calculations using GGA-PBE and HSE06 functionals, ZnSe crystal is a direct-zone crystal with a minimum bandgap width of 2.36 eV and anisotropic electronic distribution. It was found that a thermal treatment of synthesized nanocomposites at 800 °C results in an increase in ZnSe nanocrystallites size as well as an increase in emission intensity of created precipitates in a broad UV-VIS spectra range. However, vacuum conditions of annealing still do not completely prevent the oxidation of zinc selenide, and a formation of hexagonal ZnO phase is registered in the annealed samples. The current-voltage characteristics of the synthesized nanocomposites proved to have n-type conductivity, as well as increased conductivity after annealing.
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Broadband spectrum detectors exhibit great promise in fields such as multispectral imaging and optical communications. Despite significant progress, challenges like materials instability in such devices, complex manufacturing process, and high cost still hinder their further application. Here, we present a method that achieves broadband spectral detection by impurity-level in SrSnO3. We report over 500 mA/W photoresponsivity at 275 nm (ultraviolet C solar-bind) and 367 nm (ultraviolet A) and â¼60 mA/W photoresponsivity at 532 and 700 nm (visible) with a voltage bias of -5 V. Further transport and photoluminescence results reveal a new phase transition at 88 K, which would significantly affect the impurity level of the La-doped SrSnO3 film, indicating that the broadband response attributes to the impurity levels and mutual interactions. Additionally, the photodetector demonstrates excellent robustness and stability under repeated tests and prolonged exposure in air. These findings show the potential of SrSnO3 as a material for photodetectors and propose a method to achieve broadband spectrum detection, creating new possibility for the development of single-phase, low-cost, simple structure, and high-efficiency photodetectors.
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A fixed Nd3+ and varied Yb3+ ion concentration were incorporated in a Zinc-Silicate (SZNYX) composite solution using ex-situ sol-gel solution to fabricate a novel thin film (TF) on Si (100)-substrate. The upconversion luminescence (UCL) spectra of the thin films were measured under 980 nm laser excitation, with the most optimized result for Yb3+ ion concentration of 1.5 mol%. Additionally, a 2-D photoluminescence (PL) confocal mapping of the SZNY15-TF material confirmed uniform PL distribution throughout the space under the same excitation wavelength. Structural characterization via XRD revealed the tetragonal Zn2SiO4 nano-crystalline nature of the film at three distinct annealing temperatures. Morphological characterization using the Field-emission scanning electron Microscope (FESEM) coupled with energy dispersion spectrometer (EDS) affirmed the nanoflower structure and the purity of doping purity in the samples, respectively. These findings collectively confirm the promising UCL properties of the SZNYX-TF samples, suggesting potential applications in photonic.
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In preclinical drug discovery, at the step of lead optimization of a compound, in vivo experimentation can differentiate several compounds in terms of efficacy and potency in a biological system of whole living organisms. For the lead optimization study, it may be desirable to implement a dose-response design so that compound comparisons can be made from nonlinear curves fitted to the data. A dose-response design requires more thought relative to a simpler study design, needing parameters for the number of doses, the dose values, and the sample size per dose. This tutorial illustrates how to calculate statistical power, choose doses, and determine sample size per dose for a comparison of two or more dose-response curves for a future in vivo study.
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Shuffling-type gradient method is a popular machine learning algorithm that solves finite-sum optimization problems by randomly shuffling samples during iterations. In this paper, we explore the convergence properties of shuffling-type gradient method under mild assumptions. Specifically, we employ the bandwidth-based step size strategy that covers both monotonic and non-monotonic step sizes, thereby providing a unified convergence guarantee in terms of step size. Additionally, we replace the lower bound assumption of the objective function with that of the loss function, thereby eliminating the restrictions on the variance and the second-order moment of stochastic gradient that are difficult to verify in practice. For non-convex objectives, we recover the last iteration convergence of shuffling-type gradient algorithm with a less cumbersome proof. Meanwhile, we also establish the convergence rate for the minimum iteration of gradient norms. Under the Polyak-Lojasiewicz (PL) condition, we prove that the function value of last iteration converges to the lower bound of the objective function. By selecting appropriate boundary functions, we further improve the previous sublinear convergence rate results. Overall, this paper contributes to the understanding of shuffling-type gradient method and its convergence properties, providing insights for optimizing finite-sum problems in machine learning. Finally, numerical experiments demonstrate the efficiency of shuffling-type gradient method with bandwidth-based step size and validate our theoretical results.
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Pedalium Murex leaf extract was used in this study to create Nickel-doped Cerium oxide (Ni-CeO2) nanoparticles at 3 mol% and 5 mol% molar concentrations. The biosynthesized process was applied for the fabrication of Ni-CeO2 NPs. The X-ray diffraction method was used to identify their crystal structure. The XRD measurements showed that the Ni-CeO2 NPs crystallized into the face-centred cubic system. Fourier transform infrared spectral study was applied to explore the molecular vibrations and chemical bonding. The surface texture and chemical ingredients of Ni-CeO2 NPs were studied using field-emission scanning electron microscopy and energy-dispersive X-ray analysis. The EDX mapping spectra illustrate the uniform dispersal of Ce, Ni, and O atoms over the sample's surface. X-ray photoelectron spectroscopy (XPS) was conducted to confirm the chemical state of the Ni-CeO2 NPs. UV-Vis spectrum study was performed to ascertain the photon absorption, bandgap, and Urbach edge of Ni-CeO2 NPs. Photoluminescence (PL) research has been used to study the light-emitting characteristic of Ni-CeO2 NPs. The emissive intensity transition corresponding to Ni-CeO2 NPs was found to increase with the dopant level. The CIE 1931 chromaticity map was plotted to find the aptness of the samples for optical uses. The antifungal ability of Ni-CeO2 NPs was evaluated against the fungi candida albicans and candida krusein with the agar well-diffusion process. The fungicidal activity of the 3 mol% Ni doped CeO2 nanoparticles has shown a maximum zone of inhibition. The experimental findings illustrate the utility of Ni-CeO2 NPs for optical and antifungal applications.
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In the global fight against the COVID-19 pandemic caused by the highly transmissible SARS-CoV-2 virus, the search for potent medications is paramount. With a focused investigation on the SARS-CoV-2 papain-like protease (PLpro) as a promising therapeutic target due to its pivotal role in viral replication and immune modulation, the catalytic triad of PLpro comprising Cys111, His272, and Asp286, highlights Cys111 as an intriguing nucleophilic center for potential covalent bonds with ligands. The detailed analysis of the binding site unveils crucial interactions with both hydrophobic and polar residues, demonstrating the structural insights of the cavity and deepening our understanding of its molecular landscape. The sequence of PLpro among variants of concern (Alpha, Beta, Gamma, Delta and Omicron) and the recent variant of interest, JN.1, remains conserved with no mutations at the active site. Moreover, a thorough exploration of apo, non-covalently bound, and covalently bound PLpro conformations exposes significant conformational changes in loop regions, offering invaluable insights into the intricate dynamics of ligand-protein complex formation. Employing strategic in silico medication repurposing, this study swiftly identifies potential molecules for target inhibition. Within the domain of covalent docking studies and molecular dynamics, using reported inhibitors and clinically tested molecules elucidate the formation of stable covalent bonds with the cysteine residue, laying a robust foundation for potential therapeutic applications. These details not only deepen our comprehension of PLpro inhibition but also play a pivotal role in shaping the dynamic landscape of COVID-19 treatment strategies.
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Constructing self-assembly with definite assembly structure-property correlation is of great significance for expanding the property richness and functional diversity of metal nanoclusters (NCs). Herein, a well-designed liquid reaction strategy was developed through which a highly ordered nanofiber superstructure with enhanced green photoluminescence (PL) was obtained via self-assembly of the individual silver nanoclusters (Ag NCs). By visual monitoring of the kinetic reaction process using time-dependent and in situ spectroscopy measurements, the assembling structure growth and the structure-determined luminescence mechanisms were revealed. The as-prepared nanofibers featured a series of advantages involving a high emission efficiency, large Stokes shift, homogeneous chromophore, excellent photostability, high temperature, and pH sensibility. By virtue of these merits, they were successfully employed in various fields of luminescent inks, encryption and anticounterfeiting platforms, and optoelectronic light-emitting diode (LED) devices.
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BACKGROUND: Dermatomyositis (DM) is an idiopathic immune-mediated myopathy, and may involve many organs, including muscles, skin and lungs. Myositis-specific autoantibodies (MSAs) are a useful aid in diagnosis DM and identifying its clinical subtype. During the COVID-19 pandemic, several studies found clinical similarities regarding lung involvement in both COVID-19 and DM. Such similarities have prompted speculation of a common pathogenetic mechanism. Indeed, viral infections are well-known triggers of autoimmune diseases. This prompted us to investigate whether circulating MSAs could be markers of the severity of lung involvement and of clinical outcome in COVID-19 patients. Moreover, we investigated the presence of cutaneous signs of DM in COVID-19 patients. METHODS: We conducted a retrospective cohort study on 178 hospitalized patients affected by COVID-19. The diagnosis was confirmed by naso-pharyngeal swab positivity for SARS-CoV-2. The severity of lung involvement was assessed by assigning to each patient a radiological score ranging from 1 to 4, based on chest imaging (chest X-rays or CT scans). Serum samples were tested for MSAs. RESULTS: Anti-PL-7 antibodies were detected in 10.1% of patients and were found to be associated with an increased risk of severe pulmonary involvement (p = 0.019) and a worse prognosis in COVID-19 patients. Cutaneous lesions were observed in 26.4% of patients. However, none were cutaneous manifestations of DM. CONCLUSIONS: The detection of anti-PL7 antibodies might predict severe pulmonary involvement and a worse prognosis in COVID-19 patients.
Subject(s)
Autoantibodies , COVID-19 , Severity of Illness Index , Humans , COVID-19/immunology , COVID-19/diagnostic imaging , Retrospective Studies , Male , Female , Middle Aged , Autoantibodies/blood , Aged , Dermatomyositis/immunology , Dermatomyositis/diagnostic imaging , Dermatomyositis/diagnosis , Adult , Prevalence , SARS-CoV-2/immunology , Lung/diagnostic imaging , Lung/immunology , Myositis/immunology , Myositis/diagnostic imagingABSTRACT
Retinoblastoma is the most common pediatric intraocular malignant tumor affecting 1:15 000-1:20 000 live births. Even though the survival rate in developed countries is over 90â¯%, more efficient treatment options are needed for better vision salvage and reduction of the adverse effects. Therefore, we investigated fluorescein-labeled PL3 peptide targeting properties towards the Y79 retinoblastoma cell line in vitro. Through the application of cellular imaging and flow cytometry techniques, the PL3 peptide exhibited a rapid and specific internalization within Y79 cells, with subsequent translocation to the cell nuclei, showcasing notable accumulation in the nucleoli. This phenomenon was not present in other investigated cell lines and was not observable with similarly charged and length control peptide. However, the exact mechanism behind this Y79 cell line-specific nuclear and nucleolar targeting pattern remains elusive. In the future, this targeting process could facilitate specific treatment modalities of retinoblastoma with PL3 peptide-coupled drug delivery technologies.
Subject(s)
Cell Nucleolus , Retinoblastoma , Retinoblastoma/metabolism , Retinoblastoma/drug therapy , Humans , Cell Line, Tumor , Cell Nucleolus/metabolism , Cell Nucleolus/drug effects , Peptides/pharmacology , Retinal Neoplasms/metabolism , Retinal Neoplasms/drug therapy , Cell-Penetrating Peptides/pharmacologyABSTRACT
Research indicates that COVID-19 has had adverse effects on the mental health of adolescents, exacerbating their negative psychological states. The purpose of this study is to investigate the impact of Physical Literacy (PL) on Negative Mental State caused by COVID-19 (NMSC) and identify potential factors related to NMSC and PL in Chinese adolescents. This cross-sectional study involved a total of 729 Chinese high school students with an average age of 16.2 ± 1.1 years. Participants' demographic data, PL data, and NMSC data were collected. PL and NMSC were measured using the self-reported Portuguese Physical Literacy Assessment Questionnaire (PPLA-Q), the Stress and Anxiety to Viral Epidemics-6 (SAVE-6), and the Fear of COVID-19 Scale (FCV-19). Adolescents in the current study demonstrated higher levels of NMSC and lower PL, with average scores of 3.45 and 2.26, respectively (on a scale of 5). Through multiple linear regression analysis, Motivation (MO), Confidence (CO), Emotional Regulation (ER), and Physical Regulation (PR) were identified as factors influencing NMSC in adolescents. The study findings contribute to providing guidance for actions aimed at alleviating NMSC among adolescents.
Subject(s)
COVID-19 , Resilience, Psychological , Adolescent , Female , Humans , Male , China/epidemiology , COVID-19/psychology , COVID-19/epidemiology , COVID-19/prevention & control , Cross-Sectional Studies , East Asian People , Health Literacy/statistics & numerical data , Mental Health , Surveys and QuestionnairesABSTRACT
GaN on Si plays an important role in the integration and promotion of GaN-based wide-gap materials with Si-based integrated circuits (IC) technology. A series of GaN film materials were grown on Si (111) substrate using a unique plasma assistant molecular beam epitaxy (PA-MBE) technology and investigated using multiple characterization techniques of Nomarski microscopy (NM), high-resolution X-ray diffraction (HR-XRD), variable angular spectroscopic ellipsometry (VASE), Raman scattering, photoluminescence (PL), and synchrotron radiation (SR) near-edge X-ray absorption fine structure (NEXAFS) spectroscopy. NM confirmed crack-free wurtzite (w-) GaN thin films in a large range of 180-1500 nm. XRD identified the w- single crystalline structure for these GaN films with the orientation along the c-axis in the normal growth direction. An optimized 700 °C growth temperature, plus other corresponding parameters, was obtained for the PA-MBE growth of GaN on Si, exhibiting strong PL emission, narrow/strong Raman phonon modes, XRD w-GaN peaks, and high crystalline perfection. VASE studies identified this set of MBE-grown GaN/Si as having very low Urbach energy of about 18 meV. UV (325 nm)-excited Raman spectra of GaN/Si samples exhibited the GaN E2(low) and E2(high) phonon modes clearly without Raman features from the Si substrate, overcoming the difficulties from visible (532 nm) Raman measurements with strong Si Raman features overwhelming the GaN signals. The combined UV excitation Raman-PL spectra revealed multiple LO phonons spread over the GaN fundamental band edge emission PL band due to the outgoing resonance effect. Calculation of the UV Raman spectra determined the carrier concentrations with excellent values. Angular-dependent NEXAFS on Ga K-edge revealed the significant anisotropy of the conduction band of w-GaN and identified the NEXAFS resonances corresponding to different final states in the hexagonal GaN films on Si. Comparative GaN material properties are investigated in depth.
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Silicon in its nanoscale range offers a versatile scope in biomedical, photovoltaic, and solar cell applications. Due to its compatibility in integration with complex molecules owing to changes in charge density of as-fabricated Silicon Nanostructures (SiNSs) to realize label-free and real-time detection of certain biological and chemical species with certain biomolecules, it can be exploited as an indicator for ultra-sensitive and cost-effective biosensing applications in disease diagnosis. The morphological changes of SiNSs modified receptors (PNA, DNA, etc) have huge future scope in optimized sensitivity (due to conductance variations of SiNSs) of target biomolecules in health care applications. Further, due to the unique optical and electrical properties of SiNSs realized using the chemical etching technique, they can be used as an indicator for photovoltaic and solar cell applications. In this work, emphasis is given on different critical parameters that control the fabrication morphologies of SiNSs using metal-assisted chemical etching technique (MACE) and its corresponding fabrication mechanisms focusing on numerous applications in energy storage and health care domains. The evolution of MACE as a low-cost, easy process control, reproducibility, and convenient fabrication mechanism makes it a highly reliable-process friendly technique employed in photovoltaic, energy storage, and biomedical fields. Analysis of the experimental fabrication to obtain high aspect ratio SiNSs was carried out using iMAGEJ software to understand the role of surface-to-volume ratio in effective bacterial interfacing. Also, the role of silicon nanomaterials has been discussed as effective anti-bacterial surfaces due to the presence of silver investigated in the post-fabrication energy dispersive x-ray spectroscopy analysis using MACE.
Subject(s)
Nanostructures , Silicon , Silicon/chemistry , Nanostructures/chemistry , Biosensing Techniques/methods , Solar Energy , Humans , Nanotechnology/methods , Nanotechnology/economicsABSTRACT
Probiotics are posited to enhance exercise performance by influencing muscle protein synthesis, augmenting glycogen storage, and reducing inflammation. This double-blind study randomized 88 participants to receive a six-week intervention with either a placebo, Lactococcus lactis subsp. lactis LY-66, Lactobacillus plantarum PL-02, or a combination of both strains, combined with a structured exercise training program. We assessed changes in maximal oxygen consumption (VO2max), exercise performance, and gut microbiota composition before and after the intervention. Further analyses were conducted to evaluate the impact of probiotics on exercise-induced muscle damage (EIMD), muscle integrity, and inflammatory markers in the blood, 24 and 48 h post-intervention. The results demonstrated that all probiotic groups exhibited significant enhancements in exercise performance and attenuation of muscle strength decline post-exercise exhaustion (p < 0.05). Notably, PL-02 intake significantly increased muscle mass, whereas LY-66 and the combination therapy significantly reduced body fat percentage (p < 0.05). Analysis of intestinal microbiota revealed an increase in beneficial bacteria, especially a significant rise in Akkermansia muciniphila following supplementation with PL-02 and LY-66 (p < 0.05). Overall, the combination of exercise training and supplementation with PL-02, LY-66, and their combination improved muscle strength, explosiveness, and endurance performance, and had beneficial effects on body composition and gastrointestinal health, as evidenced by data obtained from non-athlete participants.
Subject(s)
Gastrointestinal Microbiome , Lactobacillus plantarum , Lactococcus lactis , Muscle Strength , Physical Endurance , Probiotics , Humans , Probiotics/administration & dosage , Double-Blind Method , Male , Physical Endurance/physiology , Female , Adult , Young Adult , Oxygen Consumption , Muscle, Skeletal/physiology , Exercise/physiologyABSTRACT
Background: Proboscis lateralis (PL) is a rare congenital malformation of the craniofacial structure. On the basis of 34 reported cases, Boo-Chai developed the first classification system in 1985 based on commonly associated anomalies of the eyes, palate, and lips. Sinonasal deformity is the most prevalent systemic abnormality associated with PL, accounting for 87.9%, and concomitant ocular anomalies account for 44-70%. Case Description: We report a case of PL in a 20-month-old female patient with a mass in the left medial canthal area, and ipsilateral symptomatic epiphora. The removal of the proboscis at 4 months without the reconstruction of the nasolacrimal duct resulted in secondary sequelae that lasted 16 months. A second operation by a multidisciplinary team released the pressure on the lacrimal sac and reconstructed the lacrimal system. External dacryocystorhinostomy (DCR) is performed through the original external incision aided by nasal endoscopic examination. The bony passage between the nasal cavity and the lacrimal sac was reconstructed, and nasal endoscopy revealed a wide opening in the nasal cavity of at least 6 mm. Follow ups ensured a patent nasal airway, without complications. Conclusions: It is instructive to learn from this case that treatment plans for PL should consider associated ocular anomalies and lacrimal drainage reconstruction, following a comprehensive and multidisciplinary approach.
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Currently, tuberculosis immunoprophylaxis is based solely on Bacillus Calmette-Guérin (BCG) vaccination, and some of the new potential tuberculosis vaccines are based on the BCG genome. Therefore, it is reasonable to analyze the genomes of individual BCG substrains. The aim of this study was the genetic characterization of the BCG-Moreau Polish (PL) strain used for the production of the BCG vaccine in Poland since 1955. Sequencing of different BCG lots showed that the strain was stable over a period of 59 years. As a result of comparison, BCG-Moreau PL with BCG-Moreau Rio de Janeiro (RDJ) 143 single nucleotide polymorphisms (SNPs) and 32 insertion/deletion mutations (INDELs) were identified. However, the verification of these mutations showed that the most significant were accumulated in the BCG-Moreau RDJ genome. The mutations unique to the Polish strain genome are 1 SNP and 2 INDEL. The strategy of combining short-read sequencing with long-read sequencing is currently the most optimal approach for sequencing bacterial genomes. With this approach, the only available genomic sequence of BCG-Moreau PL was obtained. This sequence will primarily be a reference point in the genetic control of the stability of the vaccine strain in the future. The results enrich knowledge about the microevolution and attenuation of the BCG vaccine substrains. IMPORTANCE: The whole genome sequence obtained is the only genomic sequence of the strain that has been used for vaccine production in Poland since 1955. Sequencing of different BCG lots showed that the strain was stable over a period of 59 years. The comprehensive genomic analysis performed not only enriches knowledge about the microevolution and attenuation of the BCG vaccine substrains but also enables the utilization of identified markers as a reference point in the genetic control and identity tests of the stability of the vaccine strain in the future.