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1.
Development ; 151(15)2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38975838

RESUMO

Cohesin, a chromatin-associated protein complex with four core subunits (Smc1a, Smc3, Rad21 and either Stag1 or 2), has a central role in cell proliferation and gene expression in metazoans. Human developmental disorders termed 'cohesinopathies' are characterized by germline variants of cohesin or its regulators that do not entirely eliminate cohesin function. However, it is not clear whether mutations in individual cohesin subunits have independent developmental consequences. Here, we show that zebrafish rad21 or stag2b mutants independently influence embryonic tailbud development. Both mutants have altered mesoderm induction, but only homozygous or heterozygous rad21 mutation affects cell cycle gene expression. stag2b mutants have narrower notochords and reduced Wnt signaling in neuromesodermal progenitors as revealed by single-cell RNA sequencing. Stimulation of Wnt signaling rescues transcription and morphology in stag2b, but not rad21, mutants. Our results suggest that mutations altering the quantity versus composition of cohesin have independent developmental consequences, with implications for the understanding and management of cohesinopathies.


Assuntos
Proteínas de Ciclo Celular , Proteínas Cromossômicas não Histona , Coesinas , Mutação , Proteínas de Peixe-Zebra , Peixe-Zebra , Peixe-Zebra/embriologia , Peixe-Zebra/genética , Peixe-Zebra/metabolismo , Animais , Proteínas de Ciclo Celular/metabolismo , Proteínas de Ciclo Celular/genética , Proteínas Cromossômicas não Histona/metabolismo , Proteínas Cromossômicas não Histona/genética , Proteínas de Peixe-Zebra/metabolismo , Proteínas de Peixe-Zebra/genética , Mutação/genética , Regulação da Expressão Gênica no Desenvolvimento , Via de Sinalização Wnt/genética , Desenvolvimento Embrionário/genética , Dosagem de Genes , Mesoderma/metabolismo , Mesoderma/embriologia
2.
bioRxiv ; 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-39026718

RESUMO

BACKGROUND: High-risk neuroblastoma (HR-NBL) is an aggressive tumor of the sympathetic nervous system with high risk of relapse and poor overall survival. Allogeneic hematopoietic cell transplant (allo-HCT) has been used previously in HR-NBL patients; however, graft-versus-host-disease (GVHD) and disease progression have limited clinical application. Ex-vivo stimulated allogeneic natural killer (NK) cells represent a potential approach to enhance the graft-versus-tumor (GVT) effect without exacerbation of GVHD but have not shown efficacy in NBL. METHODS: Ex-vivo stimulated NK cells from C57BL/6NCr (B6) mice were expanded with soluble IL-15/IL-15Rα alone or with irradiated CD137L/CD54+ AgN2a-4P (15-4P) at a 1:1 ratio for 10-12 days. Allogeneic NK cells were then analyzed for activation, proliferation, cytokine production, and cytotoxicity against two murine NBL cell lines, Neuro2a and NXS2, in the absence or presence of anti-TIM-3. Lethally irradiated B6AJF1 Mice received allo-HCT from B6 donors followed by NBL challenge after 7 days to mimic tumor relapse. Select groups received anti-TIM-3 starting on day 9 for every 4 days with/without infusions of 15-4P B6 NK cells on days 14, 21, and 28. In select experiments, T cell and NK cells were selectively depleted to establish their contribution to the GVT effect. All groups were analyzed for tumor growth, GVHD and overall survival. RESULTS: Co-culturing NK cells with 15-4P results in 78-fold expansion with increased expression of Ki-67 and NKG2D, NKp46, TRAIL and TIM-3. 15-4P stimulated allogeneic NK cells showed enhanced cytotoxicity against NBL compared to IL-15 NK cells alone but was limited in part due to high expression of TIM-3 ligands on Neuro-2a compared to NXS2. The addition of TIM-3 blockade further enhanced NK cytotoxicity versus Neuro-2a, with enhanced 15-4P NK cell degranulation, Eomes, TRAIL and FasL expression observed. Analysis of RNA from 15-4P NK cells exposed to TIM-3 blockade showed gene expression of chemokines, NKG2D/DAP12 signaling, non-canonical NF-κb pathway and TRAIL signaling. Blockade of NKG2D, TRAIL or FasL on 15-4P NK cells abrogated cytotoxicity. In vivo, the combination of 15-4P stimulated allogeneic NK cells and TIM-3 blockade after allo-HCT resulted in prolonged survival against NBL with decreased tumor burden compared to NK cells or anti-TIM-3 alone, without inducing GVHD. Depletion of NK cells, but not T cells, abrogated the GVT effect. CONCLUSION: Allo-HCT can be a platform for treating NBL using combination ex-vivo stimulated allogeneic NK cell therapy with TIM-3 blockade to enhance the GVT effect without inducing GVHD.

3.
Acta Crystallogr E Crystallogr Commun ; 80(Pt 7): 777-782, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38974158

RESUMO

In the title compound, C19H18BrFN2O, the pyrrolidine ring adopts an envelope conformation. In the crystal, mol-ecules are linked by inter-molecular N-H⋯O, C-H⋯O, C-H⋯F and C-H⋯Br hydrogen bonds, forming a three-dimensional network. In addition, C-H⋯π inter-actions connect mol-ecules into ribbons along the b-axis direction, consolidating the mol-ecular packing. The inter-molecular inter-actions in the crystal structure were qu-anti-fied and analysed using Hirshfeld surface analysis.

4.
Front Public Health ; 12: 1371996, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38993707

RESUMO

Background: To combat the hesitancy towards implementing a hepatitis A universal mass vaccination (UMV) strategy and to provide healthcare authorities with a comprehensive analysis of the potential outcomes and benefits of the implementation of such a vaccination program, we projected HAV seroprevalence and incidence rates in the total population of the Russian Federation and estimated the pediatric vaccination threshold required to achieve an incidence level of less than 1 case per 100,000 using a new mathematical model. Methods: A dynamic age-structured SEIRV (susceptible-exposed-infectious-recovered-vaccinated) compartmental model was developed and calibrated using demographic, seroprevalence, vaccination, and epidemiological data from different regions of the Russian Federation. This model was used to project various epidemiological measures. Results: The projected national average age at the midpoint of population immunity increases from 40 years old in 2020 to 50 years old in 2036 and is shifted even further to the age of 70 years in some regions of the country. An increase of varying magnitude in the incidence of symptomatic HAV infections is predicted for all study regions and for the Russian Federation as a whole between 2028 and 2032, if the HAV vaccination coverage level remains at the level of 2022. The national average vaccination coverage level required to achieve a symptomatic HAV incidence rate below 1 case per 100,000 by 2032 was calculated to be 69.8% if children aged 1-6 years are vaccinated following the implementation of a UMV program or 34.8% if immunization is expanded to children aged 1-17 years. Conclusion: The developed model provides insights into a further decline of herd immunity to HAV against the background of ongoing viral transmission. The current favorable situation regarding hepatitis A morbidity is projected to be replaced by an increase in incidence rates if vaccination coverage remains at the current levels. The obtained results support the introduction of a hepatitis A UMV strategy in the Russian Federation.


Assuntos
Vacinas contra Hepatite A , Hepatite A , Humanos , Hepatite A/epidemiologia , Hepatite A/prevenção & controle , Federação Russa/epidemiologia , Criança , Incidência , Pré-Escolar , Vacinas contra Hepatite A/administração & dosagem , Adolescente , Adulto , Pessoa de Meia-Idade , Lactente , Estudos Soroepidemiológicos , Idoso , Masculino , Feminino , Adulto Jovem , Vacinação em Massa/estatística & dados numéricos , Modelos Teóricos , Vacinação/estatística & dados numéricos
5.
bioRxiv ; 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38979286

RESUMO

With within-species genetic diversity estimates that span the gambit of that seen across the entirety of animals, the Caenorhabditis genus of nematodes holds unique potential to provide insights into how population size and reproductive strategies influence gene and genome organization and evolution. Our study focuses on Caenorhabditis brenneri, currently known as one of the most genetically diverse nematodes within its genus and metazoan phyla. Here, we present a high-quality gapless genome assembly and annotation for C. brenneri, revealing a common nematode chromosome arrangement characterized by gene-dense central regions and repeat rich peripheral parts. Comparison of C. brenneri with other nematodes from the 'Elegans' group revealed conserved macrosynteny but a lack of microsynteny, characterized by frequent rearrangements and low correlation iof orthogroup sizes, indicative of high rates of gene turnover. We also assessed genome organization within corresponding syntenic blocks in selfing and outcrossing species, affirming that selfing species predominantly experience loss of both genes and intergenic DNA. Comparison of gene structures revealed strikingly small number of shared introns across species, yet consistent distributions of intron number and length, regardless of population size or reproductive mode, suggesting that their evolutionary dynamics are primarily reflective of functional constraints. Our study provides valuable insights into genome evolution and expands the nematode genome resources with the highly genetically diverse C. brenneri, facilitating research into various aspects of nematode biology and evolutionary processes.

6.
Cureus ; 16(6): e62382, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-39006707

RESUMO

Minoxidil is an effective and relatively safe topical drug that is used to treat androgenetic alopecia and other types of alopecia. This active ingredient is used in dermatology as a hair growth stimulant; however, the use of solutions containing minoxidil can be accompanied by a variety of cardiovascular systemic side effects. In this case report, we describe the case of a 23-year-old man who presented with complaints of dizziness, blurred vision, general malaise, fatigue, and feeling pre-syncopal while standing after applying large amounts of topical minoxidil solution for three days in a row. Other potential causes of the presenting condition were excluded. The symptoms quickly resolved after the discontinuation of minoxidil. No other treatment was used apart from minoxidil withdrawal.

7.
Molecules ; 29(14)2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-39064826

RESUMO

In the past, polyacrylamide hydrogel was a popular choice for breast augmentation filler, and many women underwent mammoplasty with this gel. However, due to frequent complications, the use of polyacrylamide hydrogel in mammoplasty has been banned. Despite this ban, patients experiencing complications still seek medical treatment. The aim of this study was to investigate the fate of the polymer over a defined implantation period. Biopsies of breast implants were obtained from patients with 23 and 27 years of post-mammoplasty. These biopsies were meticulously purified from biological impurities and subjected to analysis using IR spectrometry, liquid chromatography-mass spectrometry, gas chromatography, and differential scanning calorimetry. The findings revealed the presence of polyacrylamide hydrogel residues, along with degradation products, within the infected material. Notably, the low-molecular-weight degradation products revealed via gas chromatography are aggressive and toxic substances capable of inducing chronic inflammation. This study sheds light on the long-term consequences of polyacrylamide hydrogel implantation, highlighting the persistence of harmful degradation products and their role in exacerbating patient complications.


Assuntos
Resinas Acrílicas , Inflamação , Humanos , Resinas Acrílicas/química , Feminino , Glândulas Mamárias Humanas/metabolismo , Glândulas Mamárias Humanas/patologia , Implantes de Mama/efeitos adversos , Adulto , Mamoplastia , Pessoa de Meia-Idade
8.
Microorganisms ; 12(7)2024 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-39065035

RESUMO

Planctomycetes of the genus Singulisphaera are common inhabitants of soils and peatlands. Although described members of this genus are characterized as possessing hydrolytic capabilities, the ability to degrade chitin has not yet been reported for these bacteria. In this study, a novel Singulisphaera representative, strain Ch08, was isolated from a chitinolytic enrichment culture obtained from a boreal fen in Northern European Russia. The 16S rRNA gene sequence of this isolate displayed 98.2% similarity to that of Singulisphaera acidiphila MOB10T. Substrate utilization tests confirmed that strain Ch08 is capable of growth on amorphous chitin. The complete genome of strain Ch08 determined in this study was 10.85 Mb in size and encoded two predicted chitinases, which were only distantly related to each other and affiliated with the glycoside hydrolase family GH18. One of these chitinases had a close homologue in the genome of S. acidiphila MOB10T. The experimental verification of S. acidiphila MOB10T growth on amorphous chitin was also positive. Transcriptome analysis performed with glucose- and chitin-growth cells of strain Ch08 showed upregulation of the predicted chitinase shared by strain Ch08 and S. acidiphila MOB10T. The gene encoding this protein was expressed in Escherichia coli, and the endochitinase activity of the recombinant enzyme was confirmed. The ability to utilize chitin, a major constituent of fungal cell walls and arthropod exoskeletons, appears to be one of the previously unrecognized ecological functions of Singulisphaera-like planctomycetes.

9.
J Biomed Sci ; 31(1): 75, 2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-39044206

RESUMO

BACKGROUND: Among the non-traditional antibacterial agents in development, only a few targets critical Gram-negative bacteria such as carbapenem-resistant Pseudomonas aeruginosa, Acinetobacter baumannii or cephalosporin-resistant Enterobacteriaceae. Endolysins and their genetically modified versions meet the World Health Organization criteria for innovation, have a novel mode of antibacterial action, no known bacterial cross-resistance, and are being intensively studied for application against Gram-negative pathogens. METHODS: The study presents a multidisciplinary approach, including genetic engineering of LysECD7-SMAP and production of recombinant endolysin, its analysis by crystal structure solution following molecular dynamics simulations and evaluation of antibacterial properties. Two types of antimicrobial dosage forms were formulated, resulting in lyophilized powder for injection and hydroxyethylcellulose gel for topical administration. Their efficacy was estimated in the treatment of sepsis, and pneumonia models in BALB/c mice, diabetes-associated wound infection in the leptin receptor-deficient db/db mice and infected burn wounds in rats. RESULTS: In this work, we investigate the application strategies of the engineered endolysin LysECD7-SMAP and its dosage forms evaluated in preclinical studies. The catalytic domain of the enzyme shares the conserved structure of endopeptidases containing a putative antimicrobial peptide at the C-terminus of polypeptide chain. The activity of endolysins has been demonstrated against a range of pathogens, such as Klebsiella pneumoniae, A. baumannii, P. aeruginosa, Staphylococcus haemolyticus, Achromobacter spp, Burkholderia cepacia complex and Haemophylus influenzae, including those with multidrug resistance. The efficacy of candidate dosage forms has been confirmed in in vivo studies. Some aspects of the interaction of LysECD7-SMAP with cell wall molecular targets are also discussed. CONCLUSIONS: Our studies demonstrate the potential of LysECD7-SMAP therapeutics for the systemic or topical treatment of infectious diseases caused by susceptible Gram-negative bacterial species and are critical to proceed LysECD7-SMAP-based antimicrobials trials to advanced stages.


Assuntos
Endopeptidases , Bactérias Gram-Negativas , Infecções por Bactérias Gram-Negativas , Camundongos Endogâmicos BALB C , Animais , Infecções por Bactérias Gram-Negativas/tratamento farmacológico , Camundongos , Endopeptidases/farmacologia , Endopeptidases/administração & dosagem , Bactérias Gram-Negativas/efeitos dos fármacos , Antibacterianos/farmacologia , Antibacterianos/administração & dosagem , Ratos , Masculino , Engenharia de Proteínas/métodos
10.
J Voice ; 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39048460

RESUMO

OBJECTIVES: The objective of this study is to present a novel clinical manifestation of COVID-19 with characteristic endoscopic laryngeal findings. A group of patients who reported similar symptoms, displayed akin laryngoscopic features, and received appropriate treatment is analyzed. Endoscopic images are provided and the pattern of this entity is discussed. STUDY DESIGN: This single-center descriptive analysis of a case series was performed in the General Hospital of Volos (Greece), during a 6-month period (from April 2022 to September 2022). Twenty-three patients who suffered from COVID-19 and were simultaneously diagnosed with acute laryngitis were enrolled. METHODS: Demographic data, clinical and endoscopic findings, laboratory results, and treatment courses were recorded. Descriptive statistics were performed with the statistical package SPSS (IBM Corp. Released 2017. IBM SPSS Statistics for Windows, Version 25.0. Armonk, NY: IBM Corp.). RESULTS: The majority of the patients were male and fully vaccinated, as defined by Greek legislation at the time. None of them was a smoker. All patients were infected with Severe Acute Respiratory Syndrome Coronavirus 2 for the first time and presented with acute odynophagia. The characteristic endoscopic finding was an erythematous larynx with white undetachable lesions mainly in the supraglottic area. Pooling of saliva in the pyriform fossae was an independent predicting factor for patients' hospitalization (P < 0.001). None of the patients required intubation or tracheostomy and all responded to the systemic treatment with corticosteroids and antibiotics. CONCLUSIONS: COVID-19-induced laryngitis should be considered in any patient with positive COVID-19 who complains of acute odynophagia. Fiberoptic laryngoscopy is necessary to confirm the diagnosis. In our series, timely initiation of treatment minimized the need to secure the airway and ensured a favorable prognosis.

11.
Chem Commun (Camb) ; 2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-39045825

RESUMO

Molecules with chiral boron atoms have been scarcely studied due to limited synthetic access. Herein, we report a new method for their synthesis via asymmetric insertion of arydiazoacetates into the B-H bonds of prochiral carbene-boranes NHC-BH2R. The reaction is catalyzed by the rhodium(I) complex with the chiral diene ligand tBu2-TFB, which can be conveniently prepared by diastereoselective coordination of the racemic diene with (S-Salox)Rh(CO)2. The target boranes were typically obtained in 75-90% yields with 90-95% ee.

12.
Commun Biol ; 7(1): 799, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38956304

RESUMO

In this paper, we propose a fluorescence-lifetime imaging microscopy (FLIM) multiplexing system based on the fluorogen-activating protein FAST. This genetically encoded fluorescent labeling platform employs FAST mutants that activate the same fluorogen but provide different fluorescence lifetimes for each specific protein-dye pair. All the proposed probes with varying lifetimes possess nearly identical and the smallest-in-class size, along with quite similar steady-state optical properties. In live mammalian cells, we target these chemogenetic tags to two intracellular structures simultaneously, where their fluorescence signals are clearly distinguished by FLIM. Due to the unique structure of certain fluorogens under study, their complexes with FAST mutants display a monophasic fluorescence decay, which may facilitate enhanced multiplexing efficiency by reducing signal cross-talks and providing optimal prerequisites for signal separation upon co-localized and/or spatially overlapped labeling.


Assuntos
Corantes Fluorescentes , Microscopia de Fluorescência , Microscopia de Fluorescência/métodos , Corantes Fluorescentes/química , Humanos , Animais , Fluorescência , Mutação
13.
Chempluschem ; : e202400375, 2024 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-39073319

RESUMO

А chemical modification of cellulose diacetate by phthalate and nitrate was performed to increase solubility in organic solvents and change the electrical properties. The role of substituents on the conductivity, permittivity, and polarizability of cellulose films is revealed. It has been shown that highly porous micro particles can be obtained from cellulose derivatives by a simple and technological freeze-drying method. The resulting micro sized aerogels have a predominantly spherical morphology and amorphous structure. Suspensions of porous particles of nitro- and phthalylated cellulose derivatives in silicone oil have an increased dielectric permittivity compared to cellulose diacetate particles. Produced particles are novel promising material with tunable electrical properties for advanced applications in composites, including for electrorheological fluids.

14.
Clin Transl Immunology ; 13(6): e1517, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38873124

RESUMO

Objectives: The evolution of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) necessitates rapid methods for assessing monoclonal antibody (mAb) potency against emerging variants. Authentic virus neutralisation assays are considered the gold standard for measuring virus-neutralising antibody (nAb) titres in serum. However, authentic virus-based assays pose inherent practical challenges for measuring nAb titres against emerging SARS-CoV-2 variants (e.g. storing infectious viruses and testing at biosafety level-3 facilities). Here, we demonstrate the utility of pseudovirus neutralisation assay data in conjunction with serum mAb concentrations to robustly predict nAb titres in serum. Methods: SARS-CoV-2 nAb titres were determined via authentic- and lentiviral pseudovirus-based neutralisation assays using serological data from three AZD7442 (tixagevimab-cilgavimab) studies: PROVENT (NCT04625725), TACKLE (NCT04723394) and a phase 1 dose-ranging study (NCT04507256). AZD7442 serum concentrations were assessed using immunocapture. Serum-based half-maximal inhibitory concentration (IC50) values were derived from pseudovirus nAb titres and serum mAb concentrations, and compared with in vitro IC50 measurements. Results: nAb titres measured via authentic- and lentiviral pseudovirus-based neutralisation assays were strongly correlated for the ancestral SARS-CoV-2 virus and SARS-CoV-2 Alpha. Serum AZD7442 concentrations and pseudovirus nAb titres were strongly correlated for multiple SARS-CoV-2 variants with all Spearman correlation coefficients ≥ 0.78. Serum-based IC50 values were similar to in vitro IC50 values for AZD7442, for ancestral SARS-CoV-2 and Alpha, Delta, Omicron BA.2 and Omicron BA.4/5 variants. Conclusions: These data highlight that serum mAb concentrations and pseudovirus in vitro IC50 values can be used to rapidly predict nAb titres in serum for emerging and historical SARS-CoV-2 variants.

15.
Artigo em Inglês | MEDLINE | ID: mdl-38829580

RESUMO

BACKGROUND: Rectal cancer (RC) occupies a leading position in the structure of oncological morbidity and mortality. Aberrant methylation of tumor-suppressor genes and hypomethylation of retrotransposons were shown to be detectable in cell-free DNA, circulating in the blood (cfDNA) of cancer patients, indicating the possibility to use them as diagnostic and prognosis markers. PURPOSE: Evaluation of the changes in the methylation level of LINE-1 elements and SEPTIN9 and IKZF1 genes in the cell-surface-bound cfDNA (csb-cfDNA) from the blood of RC patients after antitumor therapy at a long-term follow-up. METHODS: Blood samples were obtained from RC patients (n = 25) before treatment, after preoperative chemotherapy (3 courses according to the XELOX scheme), 10-15 days after surgery, and every 3 months during 12 months of dynamic observation. The methylation level of LINE-1, SEPTIN9, and IKZF1 in the csb-cfDNA was evaluated by quantitative methyl-specific PCR. RESULTS: The LINE-1 methylation level in the csb-cfDNA increased 1.6 times in RC patients after chemotherapy and 3 times after tumor resection versus methylation level before therapy. The SEPTIN9 gene methylation level in the csb-cfDNA decreased by 1.7 times in RC patients after chemotherapy and by 2.3 times after tumor resection compared with the values before the treatment. The IKZF1 gene methylation level decreased by 2 times in RC patients after combined therapy. Notably, all patients with relapses (n = 5) showed an increase in methylation level for the SEPTIN9 and IKZF1 genes and a decrease of methylation level for the LINE-1 elements by 2 times or more in comparison with the level 10-15 days after surgery. There were no changes in the circulating SEPTIN9, IKZF1, and LINE-1 methylation levels during the 12-month follow-up period after the combined therapy of RC patients (n = 20) without relapses. CONCLUSION: The results indicate that SEPTIN9, IKZF1, and LINE-1 methylation levels in the csb-cfDNA are potential markers of the effectiveness of antitumor therapy and early detection of relapse in RC patients.

16.
Biomedicines ; 12(6)2024 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-38927487

RESUMO

Currently, obesity is a critical global public health burden. Numerous studies have demonstrated the regulation of the pathogenesis of obesity and metabolic abnormalities by the gut microbiota and microbial factors; however, their involvement in the various degrees of obesity is not yet well understood. Previously, obesity has been shown to be associated with decreased levels of vitamin B12. Considering exclusive microbial production of vitamin B12, we hypothesized that a decrease in cobalamin levels in obese individuals may be at least partially caused by its depleted production in the intestinal tract by the commensal microbiota. In the present study, our aim was to estimate the abundance of enzymes and metabolic pathways for vitamin B12 synthesis in the gut microbiota of mouse models of alimentary and genetically determined obesity, to evaluate the contribution of the obesogenic microbiome to vitamin B12 synthesis in the gut. We have defined a significantly lower predicted abundance of enzymes and metabolic pathways for vitamin B12 biosynthesis in obese mice compared to non-obese mice, wherein enzyme depletion was more pronounced in lepr(-/-) (db/db) mice, which developed severe obesity. The predicted abundance of enzymes involved in cobalamin synthesis is strongly correlated with the representation of several microbes in high-fat diet-fed mice, while there were almost no correlations in db/db mice. Therefore, the degree of obesity and the composition of the correspondent microbiota are the main contributors to the representation of genes and pathways for cobalamin biosynthesis in the mouse gut.

17.
Polymers (Basel) ; 16(11)2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38891542

RESUMO

Chitosan takes second place of the most abundant polysaccharides naturally produced by living organisms. Due to its abundance and unique properties, such as its polycationic nature, ability to form strong elastic porous films, and antibacterial potential, it is widely used in the food industry and biomedicine. However, its low solubility in both water and organic solvents makes its application difficult. We have developed an environmentally friendly method for producing water-soluble graft copolymers of chitosan and poly (N-vinylpyrrolidone) with high grafting efficiency and a low yield of by-products. By using AFM, SEM, TGA, DSC, and XRD, it has been demonstrated that the products obtained have changed properties compared to the initial chitosan. They possess a smoother surface and lower thermal stability but are sufficient for practical use. The resulting copolymers have a higher viscosity than the original chitosan, making them a promising thickener and stabilizer for food gels. Moreover, the copolymers exhibit an antibacterial effect, suggesting their potential use as a component in smart food packaging.

18.
Int J Mol Sci ; 25(12)2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38928317

RESUMO

Imbalanced nutrition, such as a high-fat/high-carbohydrate diet, is associated with negative effects on human health. The composition and metabolic activity of the human gut microbiota are closely related to the type of diet and have been shown to change significantly in response to changes in food content and food supplement administration. Alkylresorcinols (ARs) are lipophilic molecules that have been found to improve lipid metabolism and glycemic control and decrease systemic inflammation. Furthermore, alkylresorcinol intake is associated with changes in intestinal microbiota metabolic activity. However, the exact mechanism through which alkylresorcinols modulate microbiota activity and host metabolism has not been determined. In this study, alterations in the small intestinal microbiota (SIM) and the large intestinal microbiota (LIM) were investigated in mice fed a high-fat diet with or without pentadecylresorcinol (C15) supplementation. High-throughput sequencing was applied for jejunal and colonic microbiota analysis. The results revealed that C15 supplementation in combination with a high-fat diet could decrease blood glucose levels. High-throughput sequencing analysis indicated that C15 intake significantly increased (p < 0.0001) the abundance of the probiotic bacteria Akkermansia muciniphila and Bifidobacterium pseudolongum in both the small and large intestines and increased the alpha diversity of LIM (p < 0.05), but not SIM. The preliminary results suggested that one of the mechanisms of the protective effects of alkylresorcinol on a high-fat diet is the modulation of the content of SIM and LIM and metabolic activity to increase the probiotic bacteria that alleviate unhealthy metabolic changes in the host.


Assuntos
Akkermansia , Dieta Hiperlipídica , Suplementos Nutricionais , Microbioma Gastrointestinal , Resorcinóis , Animais , Dieta Hiperlipídica/efeitos adversos , Resorcinóis/farmacologia , Camundongos , Microbioma Gastrointestinal/efeitos dos fármacos , Akkermansia/efeitos dos fármacos , Masculino , Camundongos Endogâmicos C57BL , Intestino Delgado/efeitos dos fármacos , Intestino Delgado/microbiologia , Intestino Delgado/metabolismo
19.
Front Immunol ; 15: 1401728, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38827749

RESUMO

Background: Immunity to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is now widespread; however, the degree of cross-immunity between SARS-CoV-2 and endemic, seasonal human coronaviruses (HCoVs) remains unclear. Methods: SARS-CoV-2 and HCoV cross-immunity was evaluated in adult participants enrolled in a US sub-study in the phase III, randomized controlled trial (NCT04516746) of AZD1222 (ChAdOx1 nCoV-19) primary-series vaccination for one-year. Anti-HCoV spike-binding antibodies against HCoV-229E, HCoV-HKU1, HCoV-OC43, and HCoV-NL63 were evaluated in participants following study dosing and, in the AZD1222 group, after a non-study third-dose booster. Timing of SARS-CoV-2 seroconversion (assessed via anti-nucleocapsid antibody levels) and incidence of COVID-19 were evaluated in those who received AZD1222 primary-series by baseline anti-HCoV titers. Results: We evaluated 2,020/21,634 participants in the AZD1222 group and 1,007/10,816 in the placebo group. At the one-year data cutoff (March 11, 2022) mean duration of follow up was 230.9 (SD: 106.36, range: 1-325) and 94.3 (74.12, 1-321) days for participants in the AZD1222 (n = 1,940) and placebo (n = 962) groups, respectively. We observed little elevation in anti-HCoV humoral titers post study-dosing or post-boosting, nor evidence of waning over time. The occurrence and timing of SARS-CoV-2 seroconversion and incidence of COVID-19 were not largely impacted by baseline anti-HCoV titers. Conclusion: We found limited evidence for cross-immunity between SARS-CoV-2 and HCoVs following AZD1222 primary series and booster vaccination. Susceptibility to future emergence of novel coronaviruses will likely persist despite a high prevalence of SARS-CoV-2 immunity in global populations.


Assuntos
Anticorpos Antivirais , Vacinas contra COVID-19 , COVID-19 , ChAdOx1 nCoV-19 , Imunidade Humoral , SARS-CoV-2 , Humanos , COVID-19/imunologia , COVID-19/prevenção & controle , ChAdOx1 nCoV-19/imunologia , Adulto , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , SARS-CoV-2/imunologia , Masculino , Feminino , Vacinas contra COVID-19/imunologia , Vacinas contra COVID-19/administração & dosagem , Pessoa de Meia-Idade , Imunidade Humoral/efeitos dos fármacos , Reações Cruzadas/imunologia , Estações do Ano , Adulto Jovem , Vacinação , Método Duplo-Cego
20.
Int J Mol Sci ; 25(11)2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38892289

RESUMO

Familial Mediterranean fever (FMF) is a systemic autoinflammatory disorder caused by inherited mutations in the MEFV (Mediterranean FeVer) gene, located on chromosome 16 (16p13.3) and encoding the pyrin protein. Despite the existing data on MEFV mutations, the exact mechanism of their effect on the development of the pathological processes leading to the spontaneous and recurrent autoinflammatory attacks observed in FMF, remains unclear. Induced pluripotent stem cells (iPSCs) are considered an important tool to study the molecular genetic mechanisms of various diseases due to their ability to differentiate into any cell type, including macrophages, which contribute to the development of FMF. In this study, we developed iPSCs from an Armenian patient with FMF carrying the M694V, p.(Met694Val) (c.2080A>G, rs61752717) pathogenic mutation in exon 10 of the MEFV gene. As a result of direct differentiation, macrophages expressing CD14 and CD45 surface markers were obtained. We found that the morphology of macrophages derived from iPSCs of a patient with the MEFV mutation significantly differed from that of macrophages derived from iPSCs of a healthy donor carrying the wild-type MEFV gene.


Assuntos
Diferenciação Celular , Febre Familiar do Mediterrâneo , Células-Tronco Pluripotentes Induzidas , Macrófagos , Mutação , Pirina , Humanos , Pirina/genética , Células-Tronco Pluripotentes Induzidas/metabolismo , Febre Familiar do Mediterrâneo/genética , Febre Familiar do Mediterrâneo/patologia , Macrófagos/metabolismo , Diferenciação Celular/genética , Masculino
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