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1.
Transl Androl Urol ; 13(6): 962-969, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38983481

RESUMO

Background: Although minimal is known about coronavirus disease 2019 (COVID-19)'s impact on patient healthcare perceptions, improved understanding can guide healthcare providers to adequately address patient concerns. This cross-sectional study investigated how fear induced by COVID-19 impacted nephrolithiasis patients' perceptions, decision-making, and preferences for care delivery. Methods: Utilizing the validated Fear of COVID-19 Scale (FCV-19S), patients were surveyed at a single stone clinic during part of the COVID-19 pandemic, 03/2021-04/2022. One-way analysis of variance (ANOVA), Chi-square tests, and multinomial logistic regression evaluated the effect of sociodemographics on responses. Results: Two hundred and four surveys were completed. Mean age was 58±16 years, and 112 (54.9%) were women. Mean FCV-19S was 14.8±5.8 points (range, 7-33). Women and non-Caucasian races were associated with higher fear scores (P<0.01 and P=0.01 respectively). Stone prevention effort was not associated with fear (P=0.38). Poorer self-assessed health status was associated with increased stone prevention efforts (P=0.04). Preference for in-person care was reported in 89% of patients. Willingness to seek care varied by age and education, with decreased likelihood to seek care for middle-aged patients (P=0.04) and increased education (P=0.01). Conclusions: Perceived fear during the COVID-19 pandemic was highly variable in nephrolithiasis patients, with higher fear scores in women and non-Caucasians. Willingness to seek care during the pandemic varied with age, education level, symptom severity, COVID-19 fear, current stone status, and health status. Stone patients greatly preferred in-person medical care over telemedicine during COVID-19. Future studies are needed to further evaluate these health disparities, discrepancies in fear, and comfort in seeking stone-related healthcare to help us better inform health policymakers and provide patient-centered care.

2.
Carbohydr Polym ; 340: 122210, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-38858031

RESUMO

Fluorescence labeling with N-(1-naphthyl)ethylenediamine is highly effective for quantifying oxidized reducing end groups (REGs) in cellulosic materials. When combined with size exclusion chromatography in DMAc/LiCl, along with fluorescence / multiple-angle laser light scattering / refractive index detection, a detailed profile of C1-oxidized REGs relative to the molecular weight distribution of the cellulosic material can be obtained. In this work, the derivatization process was extensively optimized, to be carried out heterogeneously in the solvent N-methyl-2-pyrrolidone. Furthermore, we show that to achieve high selectivity for carboxyl groups at the C1 position, keto and aldehyde groups need to be selectively reduced (e.g., by NaBH4), and carboxyl groups other than at C1 need to be blocked (e.g., by methylation with (trimethylsilyl)diazomethane) prior to fluorescence labeling of carboxyl groups at C1 position. Finally, we demonstrate the practical value of the analytical method by measuring the content of the C1-oxidized REGs in cellulose samples after chemical (by Pinnick oxidation) or enzymatic (by treatment with C1-oxidizing LPMO enzymes) oxidation of various pulp samples.

3.
Can J Diet Pract Res ; 85(2): 83-90, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38829673

RESUMO

Purpose: To examine the social network factors associated with changes in nutrition risk scores, measured by SCREEN-8, over three years, in community-dwelling Canadians aged 45 years and older, using data from the Canadian Longitudinal Study on Aging (CLSA).Methods: Change in SCREEN-8 scores between the baseline and first follow-up waves of the CLSA was calculated by subtracting SCREEN-8 scores at follow-up from baseline scores. Multivariable linear regression was used to examine the factors associated with change in SCREEN-8 score.Results: The mean SCREEN-8 score at baseline was 38.7 (SD = 6.4), and the mean SCREEN-8 score at follow-up was 37.9 (SD = 6.6). The mean change in SCREEN-8 score was -0.90 (SD = 5.99). Higher levels of social participation (participation in community activities) were associated with increases in SCREEN-8 scores between baseline and follow-up, three years later.Conclusions: Dietitians should be aware that individuals with low levels of social participation may be at risk for having their nutritional status decrease over time and consideration should be given to screening them proactively for nutrition risk. Dietitians can develop and support programs aimed at combining food with social participation.


Assuntos
Estado Nutricional , Humanos , Canadá , Estudos Longitudinais , Feminino , Masculino , Idoso , Pessoa de Meia-Idade , Fatores de Risco , Envelhecimento , Avaliação Nutricional , Participação Social , Fatores Sociais , Vida Independente , Idoso de 80 Anos ou mais
4.
ACS Omega ; 9(21): 23040-23052, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38826537

RESUMO

Lytic polysaccharide monooxygenases (LPMOs) catalyze the oxidative cleavage of glycosidic bonds in recalcitrant polysaccharides, such as cellulose and chitin, using a single copper cofactor bound in a conserved histidine brace with a more variable second coordination sphere. Cellulose-active LPMOs in the fungal AA9 family and in a subset of bacterial AA10 enzymes contain a His-Gln-Tyr second sphere motif, whereas other cellulose-active AA10s have an Arg-Glu-Phe motif. To shine a light on the impact of this variation, we generated single, double, and triple mutations changing the His216-Gln219-Tyr221 motif in cellulose- and chitin-oxidizing MaAA10B toward Arg-Glu-Phe. These mutations generally reduced enzyme performance due to rapid inactivation under turnover conditions, showing that catalytic fine-tuning of the histidine brace is complex and that the roles of these second sphere residues are strongly interconnected. Studies of copper reactivity showed remarkable effects, such as an increase in oxidase activity following the Q219E mutation and a strong dependence of this effect on the presence of Tyr at position 221. In reductant-driven reactions, differences in oxidase activity, which lead to different levels of in situ generated H2O2, correlated with differences in polysaccharide-degrading ability. The single Q219E mutant displayed a marked increase in activity on chitin in both reductant-driven reactions and reactions fueled by exogenously added H2O2. Thus, it seems that the evolution of substrate specificity in LPMOs involves both the extended substrate-binding surface and the second coordination sphere.

5.
Nat Commun ; 15(1): 3975, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38729930

RESUMO

Oxidoreductases have evolved tyrosine/tryptophan pathways that channel highly oxidizing holes away from the active site to avoid damage. Here we dissect such a pathway in a bacterial LPMO, member of a widespread family of C-H bond activating enzymes with outstanding industrial potential. We show that a strictly conserved tryptophan is critical for radical formation and hole transference and that holes traverse the protein to reach a tyrosine-histidine pair in the protein's surface. Real-time monitoring of radical formation reveals a clear correlation between the efficiency of hole transference and enzyme performance under oxidative stress. Residues involved in this pathway vary considerably between natural LPMOs, which could reflect adaptation to different ecological niches. Importantly, we show that enzyme activity is increased in a variant with slower radical transference, providing experimental evidence for a previously postulated trade-off between activity and redox robustness.


Assuntos
Proteínas de Bactérias , Oxigenases de Função Mista , Oxirredução , Oxigenases de Função Mista/metabolismo , Oxigenases de Função Mista/genética , Oxigenases de Função Mista/química , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/química , Domínio Catalítico , Triptofano/metabolismo , Polissacarídeos/metabolismo , Mutação , Estresse Oxidativo , Tirosina/metabolismo , Modelos Moleculares , Histidina/metabolismo , Histidina/genética
6.
Epidemiol Infect ; 152: e77, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38724258

RESUMO

This study compared the likelihood of long-term sequelae following infection with SARS-CoV-2 variants, other acute respiratory infections (ARIs) and non-infected individuals. Participants (n=5,630) were drawn from Virus Watch, a prospective community cohort investigating SARS-CoV-2 epidemiology in England. Using logistic regression, we compared predicted probabilities of developing long-term symptoms (>2 months) during different variant dominance periods according to infection status (SARS-CoV-2, other ARI, or no infection), adjusting for confounding by demographic and clinical factors and vaccination status. SARS-CoV-2 infection during early variant periods up to Omicron BA.1 was associated with greater probability of long-term sequalae (adjusted predicted probability (PP) range 0.27, 95% CI = 0.22-0.33 to 0.34, 95% CI = 0.25-0.43) compared with later Omicron sub-variants (PP range 0.11, 95% CI 0.08-0.15 to 0.14, 95% CI 0.10-0.18). While differences between SARS-CoV-2 and other ARIs (PP range 0.08, 95% CI 0.04-0.11 to 0.23, 95% CI 0.18-0.28) varied by period, all post-infection estimates substantially exceeded those for non-infected participants (PP range 0.01, 95% CI 0.00, 0.02 to 0.03, 95% CI 0.01-0.06). Variant was an important predictor of SARS-CoV-2 post-infection sequalae, with recent Omicron sub-variants demonstrating similar probabilities to other contemporaneous ARIs. Further aetiological investigation including between-pathogen comparison is recommended.


Assuntos
COVID-19 , Infecções Respiratórias , SARS-CoV-2 , Humanos , Inglaterra/epidemiologia , COVID-19/epidemiologia , COVID-19/virologia , Masculino , Feminino , Pessoa de Meia-Idade , Estudos Prospectivos , Adulto , Infecções Respiratórias/virologia , Infecções Respiratórias/epidemiologia , Idoso , Adulto Jovem , Adolescente
7.
Biomacromolecules ; 25(5): 3076-3086, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38634234

RESUMO

Despite the wide range of analytical tools available for the characterization of cellulose, the in-depth characterization of inhomogeneous, layered cellulose fiber structures remains a challenge. When treating fibers or spinning man-made fibers, the question always arises as to whether the changes in the fiber structure affect only the surface or the entire fiber. Here, we developed an analysis tool based on the sequential limited dissolution of cellulose fiber layers. The method can reveal potential differences in fiber properties along the cross-sectional profile of natural or man-made cellulose fibers. In this analytical approach, carbonyl groups are labeled with a carbonyl selective fluorescence label (CCOA), after which thin fiber layers are sequentially dissolved with the solvent system DMAc/LiCl (9% w/v) and analyzed with size exclusion chromatography coupled with light scattering and fluorescence detection. The analysis of these fractions allowed for the recording of the changes in the chemical structure across the layers, resulting in a detailed cross-sectional profile of the different functionalities and molecular weight distributions. The method was optimized and tested in practice with LPMO (lytic polysaccharide monooxygenase)-treated cotton fibers, where it revealed the depth of fiber modification by the enzyme.


Assuntos
Celulose , Celulose/química , Fibra de Algodão , Cromatografia em Gel/métodos
8.
J Migr Health ; 9: 100218, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38559897

RESUMO

Background: Migrants in the United Kingdom (UK) may be at higher risk of SARS-CoV-2 exposure; however, little is known about their risk of COVID-19-related hospitalisation during waves 1-3 of the pandemic. Methods: We analysed secondary care data linked to Virus Watch study data for adults and estimated COVID-19-related hospitalisation incidence rates by migration status. To estimate the total effect of migration status on COVID-19 hospitalisation rates, we ran mixed-effect Poisson regression for wave 1 (01/03/2020-31/08/2020; wildtype), and mixed-effect negative binomial regressions for waves 2 (01/09/2020-31/05/2021; Alpha) and 3 (01/06/2020-31/11/2021; Delta). Results of all models were then meta-analysed. Results: Of 30,276 adults in the analyses, 26,492 (87.5 %) were UK-born and 3,784 (12.5 %) were migrants. COVID-19-related hospitalisation incidence rates for UK-born and migrant individuals across waves 1-3 were 2.7 [95 % CI 2.2-3.2], and 4.6 [3.1-6.7] per 1,000 person-years, respectively. Pooled incidence rate ratios across waves suggested increased rate of COVID-19-related hospitalisation in migrants compared to UK-born individuals in unadjusted 1.68 [1.08-2.60] and adjusted analyses 1.35 [0.71-2.60]. Conclusion: Our findings suggest migration populations in the UK have excess risk of COVID-19-related hospitalisations and underscore the need for more equitable interventions particularly aimed at COVID-19 vaccination uptake among migrants.

9.
Ergonomics ; : 1-21, 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38635303

RESUMO

Although trust plays a vital role in human-robot interaction, there is currently a dearth of literature examining the effect of users' openness personality on trust in actual interaction. This study aims to investigate the interaction effects of users' openness and robot reliability on trust. We designed a voice-based walking task and collected subjective trust ratings, task metrics, eye-tracking data, and fNIRS signals from users with different openness to unravel the psychological intentions, task performance, visual behaviours, and cerebral activations underlying trust. The results showed significant interaction effects. Users with low openness exhibited lower subjective trust, more fixations, and higher activation of rTPJ in the highly reliable condition than those with high openness. The results suggested that users with low openness might be more cautious and suspicious about the highly reliable robot and allocate more visual attention and neural processing to monitor and infer robot status than users with high openness.


The study could deepen practitioners' understanding of the effect of openness on trust in robots by examining the psychological intention, task performance, visual behaviours, and physiological activations. Moreover, the interaction effect could provide guidelines for designing robots adaptive to users' personalities, and the multimodal method would be practical for measuring trust in interaction.

11.
Biotechnol Biofuels Bioprod ; 17(1): 39, 2024 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-38461298

RESUMO

BACKGROUND: The polysaccharides in lignocellulosic biomass hold potential for production of biofuels and biochemicals. However, achieving efficient conversion of this resource into fermentable sugars faces challenges, especially when operating at industrially relevant high solid loadings. While it is clear that combining classical hydrolytic enzymes and lytic polysaccharide monooxygenases (LPMOs) is necessary to achieve high saccharification yields, exactly how these enzymes synergize at high solid loadings remains unclear. RESULTS: An LPMO-poor cellulase cocktail, Celluclast 1.5 L, was spiked with one or both of two fungal LPMOs from Thermothielavioides terrestris and Thermoascus aurantiacus, TtAA9E and TaAA9A, respectively, to assess their impact on cellulose saccharification efficiency at high dry matter loading, using Avicel and steam-exploded wheat straw as substrates. The results demonstrate that LPMOs can mitigate the reduction in saccharification efficiency associated with high dry matter contents. The positive effect of LPMO inclusion depends on the type of feedstock and the type of LPMO and increases with the increasing dry matter content and reaction time. Furthermore, our results show that chelating free copper, which may leak out of the active site of inactivated LPMOs during saccharification, with EDTA prevents side reactions with in situ generated H2O2 and the reductant (ascorbic acid). CONCLUSIONS: This study shows that sustaining LPMO activity is vital for efficient cellulose solubilization at high substrate loadings. LPMO cleavage of cellulose at high dry matter loadings results in new chain ends and thus increased water accessibility leading to decrystallization of the substrate, all factors making the substrate more accessible to cellulase action. Additionally, this work highlights the importance of preventing LPMO inactivation and its potential detrimental impact on all enzymes in the reaction.

12.
Heliyon ; 10(5): e26582, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38455577

RESUMO

Online medical service robots (OMSRs) are becoming increasingly important in the medical industry, and their design has become a highly focused issue. This study investigated the neuroeconomics underlying the formation of usage intention, specifically evaluating the impact of anthropomorphic appearance and age on users' intentions to use OMSRs. Event-related potentials were used to analyze electroencephalography signals recorded from participants. This study found that OMSRs with a low anthropomorphic appearance induced larger P200 and P300 amplitudes, resulting in increased attentional resources compared to OMSRs with a moderate or high anthropomorphic appearance. OMSRs with moderate anthropomorphic appearances captured more attention and elicited larger P200 and P300 than those with high anthropomorphic appearances. Regarding age characteristics, OMSRs with senior features attracted more attention and induced larger P200 and P300 amplitudes. In terms of usage intention, compared to the others, users demonstrate a stronger usage intention towards the low anthropomorphism of OMSRs. Additionally, compared to the senior ones, users also exhibit a stronger usage intention toward a young appearance of OMSRs. These findings provide valuable insights for robot designers and practitioners to improve the appearance of OMSRs.

13.
Carbohydr Polym ; 330: 121816, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38368098

RESUMO

Lytic polysaccharide monooxygenases (LPMOs) are excellent candidates for enzymatic functionalization of natural polysaccharides, such as cellulose or chitin, and are gaining relevance in the search for renewable biomaterials. Here, we assessed the cellulose fiber modification potential and catalytic performance of eleven cellulose-active fungal AA9-type LPMOs, including C1-, C4-, and C1/C4-oxidizing LPMOs with and without CBM1 carbohydrate-binding modules, on cellulosic substrates with different degrees of crystallinity and polymer chain arrangement, namely, Cellulose I, Cellulose II, and amorphous cellulose. The potential of LPMOs for cellulose fiber modification varied among the LPMOs and depended primarily on operational stability and substrate binding, and, to some extent, also on regioselectivity and domain structure. While all tested LPMOs were active on natural Cellulose I-type fibers, activity on the Cellulose II allomorph was almost exclusively detected for LPMOs containing a CBM1 and LPMOs with activity on soluble hemicelluloses and cello-oligosaccharides, for example NcAA9C from Neurospora crassa. The single-domain variant of NcAA9C oxidized the cellulose fibers to a higher extent than its CBM-containing natural variant and released less soluble products, indicating a more dispersed oxidation pattern without a CBM. Our findings reveal great functional variation among cellulose-active LPMOs, laying the groundwork for further LPMO-based cellulose engineering.


Assuntos
Celulose , Polissacarídeos , Celulose/metabolismo , Polissacarídeos/metabolismo , Oxirredução , Oxigenases de Função Mista/química , Oligossacarídeos/metabolismo , Estresse Oxidativo
14.
Curr Issues Mol Biol ; 46(2): 1424-1436, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38392210

RESUMO

Adipose stem cells (ASCs) have multilineage differentiation capacity and hold great potential for regenerative medicine. Compared to bone marrow-derived mesenchymal stem cells (bmMSCs), ASCs are easier to isolate from abundant sources with significantly higher yields. It is generally accepted that bmMSCs show age-related changes in their proliferation and differentiation potentials, whereas this aspect is still controversial in the case of ASCs. In this review, we evaluated the existing data on the effect of donor age on the osteogenic potential of human ASCs. Overall, a poor agreement has been achieved because of inconsistent findings in the previous studies. Finally, we attempted to delineate the possible reasons behind the lack of agreements reported in the literature. ASCs represent a heterogeneous cell population, and the osteogenic potential of ASCs can be influenced by donor-related factors such as age, but also gender, lifestyle, and the underlying health and metabolic state of donors. Furthermore, future studies should consider experimental factors in in vitro conditions, including passaging, cryopreservation, culture conditions, variations in differentiation protocols, and readout methods.

15.
Cureus ; 16(1): e52994, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38406030

RESUMO

Hyperkalemia has been defined as a condition where a serum potassium level is >5.5 mmol/l. It is associated with fatal dysrhythmias and muscular dysfunction. Certain medical conditions, such as chronic kidney disease (CKD), diabetes mellitus, and others, can lead to hyperkalemia. Many of the signs of hyperkalemia are nonspecific. A history and physical examination can be beneficial in the diagnosis of the condition. In this regard, certain characteristic electrocardiogram findings are associated with hyperkalemia along with laboratory potassium levels. In acute and potentially lethal conditions, hyperkalemia treatments include glucose and insulin, bicarbonate, calcium gluconate, beta-2 agonists, hyperventilation, and dialysis. There are several drugs, both old and new, that can additionally aid in the reduction of serum potassium levels. The present investigation evaluated some of these different drugs, including sodium polystyrene sulfonate (SPS), sodium zirconium cyclosilicate (SZC), and patiromer. These drugs each have increased selectivity for potassium and work primarily in the gastrointestinal (GI) tract. Each of these medications has unique benefits and contraindications. Clinicians must be aware of these medications when managing patients with hyperkalemia.

16.
Physiol Genomics ; 56(4): 360-366, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38314697

RESUMO

Adverse cardiac remodeling contributes to heart failure development and progression, partly due to inappropriate sympathetic nervous system activation. Although ß-adrenergic receptor (ß-AR) blockade is a common heart failure therapy, not all patients respond, prompting exploration of alternative treatments. Minocycline, an FDA-approved antibiotic, has pleiotropic properties beyond antimicrobial action. Recent evidence suggests it may alter gene expression via changes in miRNA expression. Thus, we hypothesized that minocycline could prevent adverse cardiac remodeling induced by the ß-AR agonist isoproterenol, involving miRNA-mRNA transcriptome alterations. Male C57BL/6J mice received isoproterenol (30 mg/kg/day sc) or vehicle via osmotic minipump for 21 days, along with daily minocycline (50 mg/kg ip) or sterile saline. Isoproterenol induced cardiac hypertrophy without altering cardiac function, which minocycline prevented. Total mRNA sequencing revealed isoproterenol altering gene networks associated with inflammation and metabolism, with fibrosis activation predicted by integrated miRNA-mRNA sequencing, involving miR-21, miR-30a, miR-34a, miR-92a, and miR-150, among others. Conversely, the cardiac miRNA-mRNA transcriptome predicted fibrosis inhibition in minocycline-treated mice, involving antifibrotic shifts in Atf3 and Itgb6 gene expression associated with miR-194 upregulation. Picrosirius red staining confirmed isoproterenol-induced cardiac fibrosis, prevented by minocycline. These results demonstrate minocycline's therapeutic potential in attenuating adverse cardiac remodeling through miRNA-mRNA-dependent mechanisms, especially in reducing cardiac fibrosis. NEW & NOTEWORTHY We demonstrate that minocycline treatment prevents cardiac hypertrophy and fibrotic remodeling induced by chronic ß-adrenergic stimulation by inducing antifibrotic shifts in the cardiac miRNA-mRNA transcriptome.


Assuntos
Cardiomiopatias , Insuficiência Cardíaca , MicroRNAs , Humanos , Masculino , Camundongos , Animais , Isoproterenol/farmacologia , Isoproterenol/metabolismo , Minociclina/farmacologia , Miócitos Cardíacos/metabolismo , Adrenérgicos/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , RNA Mensageiro/genética , Remodelação Ventricular/genética , Camundongos Endogâmicos C57BL , Cardiomegalia/metabolismo , Insuficiência Cardíaca/induzido quimicamente , Insuficiência Cardíaca/tratamento farmacológico , Insuficiência Cardíaca/genética , Fibrose
17.
BJU Int ; 133(5): 570-578, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38332669

RESUMO

OBJECTIVE: To assess the impact of kidney stone disease (KSD) and its treatment on the health-related quality of life (HRQOL) of high-risk stone formers with hyperparathyroidism, renal tubular acidosis, malabsorptive disease, and medullary sponge kidney. PATIENTS AND METHODS: The Wisconsin Stone Quality of Life questionnaire was used to evaluate HRQOL in 3301 patients with a history of KSD from 16 institutions in North America between 2014 and 2020. Baseline characteristics and medical history were collected from patients, while active KSD was confirmed through radiological imaging. The high-risk group was compared to the remaining patients (control group) using the Wilcoxon rank-sum test. RESULTS: Of 1499 patients with active KSD included in the study, the high-risk group included 120 patients. The high-risk group had significantly lower HRQOL scores compared to the control group (P < 0.01). In the multivariable analyses, medullary sponge kidney disease and renal tubular acidosis were independent predictors of poorer HRQOL, while alkali therapy was an independent predictor of better HRQOL (all P < 0.01). CONCLUSIONS: Among patients with active KSD, high-risk stone formers had impaired HRQOL with medullary sponge kidney disease and renal tubular acidosis being independent predictors of poorer HRQOL. Clinicians should seek to identify these patients earlier as they would benefit from prompt treatment and prevention.


Assuntos
Cálculos Renais , Qualidade de Vida , Humanos , Feminino , Masculino , Cálculos Renais/complicações , Pessoa de Meia-Idade , Adulto , Idoso , Acidose Tubular Renal/complicações , Rim em Esponja Medular/complicações , Inquéritos e Questionários
18.
Microb Cell Fact ; 23(1): 19, 2024 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-38212746

RESUMO

BACKGROUND: Utilization of commensal bacteria for delivery of medicinal proteins, such as vaccine antigens, is an emerging strategy. Here, we describe two novel food-grade strains of lactic acid bacteria, Lactiplantibacillus pentosus KW1 and KW2, as well as newly developed tools for using this relatively unexplored but promising bacterial species for production and surface-display of heterologous proteins. RESULTS: Whole genome sequencing was performed to investigate genomic features of both strains and to identify native proteins enabling surface display of heterologous proteins. Basic characterization of the strains revealed the optimum growth temperatures for both strains to be 35-37 °C, with peak heterologous protein production at 33 °C (KW1) and 37 °C (KW2). Negative staining revealed that only KW1 produces closely bound exopolysaccharides. Production of heterologous proteins with the inducible pSIP-expression system enabled high expression in both strains. Exposure to KW1 and KW2 skewed macrophages toward the antigen presenting state, indicating potential adjuvant properties. To develop these strains as delivery vehicles, expression of the mycobacterial H56 antigen was fused to four different strain-specific surface-anchoring sequences. CONCLUSION: All experiments that enabled comparison of heterologous protein production revealed KW1 to be the better recombinant protein production host. Use of the pSIP expression system enabled successful construction of L. pentosus strains for production and surface display of an antigen, underpinning the potential of these strains as novel delivery vehicles.


Assuntos
Bactérias , Proteínas Recombinantes/metabolismo , Bactérias/metabolismo , Sequenciamento Completo do Genoma
20.
Nat Rev Chem ; 8(2): 106-119, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38200220

RESUMO

Lytic polysaccharide monooxygenases (LPMOs) have an essential role in global carbon cycle, industrial biomass processing and microbial pathogenicity by catalysing the oxidative cleavage of recalcitrant polysaccharides. Despite initially being considered monooxygenases, experimental and theoretical studies show that LPMOs are essentially peroxygenases, using a single copper ion and H2O2 for C-H bond oxygenation. Here, we examine LPMO catalysis, emphasizing key studies that have shaped our comprehension of their function, and address side and competing reactions that have partially obscured our understanding. Then, we compare this novel copper-peroxygenase reaction with reactions catalysed by haem iron enzymes, highlighting the different chemistries at play. We conclude by addressing some open questions surrounding LPMO catalysis, including the importance of peroxygenase and monooxygenase reactions in biological contexts, how LPMOs modulate copper site reactivity and potential protective mechanisms against oxidative damage.


Assuntos
Peróxido de Hidrogênio , Metaloproteínas , Peróxido de Hidrogênio/química , Cobre/química , Polissacarídeos/química , Oxigenases de Função Mista/química , Catálise
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