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1.
Microbiol Res ; 283: 127709, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38593579

RESUMO

Bifidobacterium longum subsp. infantis commonly colonizes the human gut and is capable of metabolizing L-fucose, which is abundant in the gut. Multiple studies have focused on the mechanisms of L-fucose utilization by B. longum subsp. infantis, but the regulatory pathways governing the expression of these catabolic processes are still unclear. In this study, we have conducted a structural and functional analysis of L-fucose metabolism transcription factor FucR derived from B. longum subsp. infantis Bi-26. Our results indicated that FucR is a L-fucose-sensitive repressor with more α-helices, fewer ß-sheets, and ß-turns. Transcriptional analysis revealed that FucR displays weak negative self-regulation, which is counteracted in the presence of L-fucose. Isothermal titration calorimetry indicated that FucR has a 2:1 stoichiometry with L-fucose. The key amino acid residues for FucR binding L-fucose are Asp280 and Arg331, with mutation of Asp280 to Ala resulting in a decrease in the affinity between FucR and L-fucose with the Kd value from 2.58 to 11.68 µM, and mutation of Arg331 to Ala abolishes the binding ability of FucR towards L-fucose. FucR specifically recognized and bound to a 20-bp incomplete palindrome sequence (5'-ACCCCAATTACGAAAATTTTT-3'), and the affinity of the L-fucose-loaded FucR for the DNA fragment was lower than apo-FucR. The results provided new insights into the regulating L-fucose metabolism by B. longum subsp. infantis.


Assuntos
Bifidobacterium longum , Bifidobacterium , Humanos , Bifidobacterium/genética , Bifidobacterium/metabolismo , Fucose/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Metabolismo dos Carboidratos , Bifidobacterium longum/genética , Bifidobacterium longum/metabolismo
2.
Front Neurol ; 15: 1352949, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38469591

RESUMO

Objective: Spontaneous hypertensive brainstem hemorrhage (HBSH) is characterized by sudden onset, rapid progression and poor prognosis. There has been a growing tendency of surgical treatment for HBSH. This study aimed to investigate outcomes and potential factors associated with the prognosis of robot-assisted drainage surgery for HBSH treatment. Methods: Patients with HBSH from July 2016 to March 2023 at a single neurosurgery center were included and divided into conservative group and surgical groups. Baseline and clinical data, radiographic characteristics, complications, and outcome evaluations were recorded and analyzed. Results: A total of 125 patients, with 74 in the conservative group and 51 in the surgical group, were enrolled in the study. Mortality at 6 months was 59/74 (79.7%) in the conservative group and 9/51 (17.6%) in the surgical group. Twenty-four patients (47.1%) achieved favorable outcomes in the surgical group, whereas this rate in the conservative group was only 5.4% (4/74). There was a significant difference in NIHSS, GCS, and mRS at 6 months between surviving patients in the conservative and surgical groups. In prognostic analysis in the surgical subgroup, initial GCS score [5 (IQR 4-7) vs. 3 (IQR 3-4), p < 0.001], NIHSS [36 (IQR 32-38) vs. 40 (IQR 38-40), p < 0.001], smoking history [45.8% (11/24) vs. 74.1% (20/27), p = 0.039], hematoma volume [6.9 (IQR 6.2-7.6) vs. 9.6 (IQR 7.3-11.4), p = 0.001], and hemorrhage location (p = 0.001) were potential risk factors for poor 6-month prognosis after robot-assisted surgery for HBSH. Conclusion: Based on the results of this study, robot-assisted minimally invasive drainage of brain stem hematoma may significantly reduce mortality and improve prognosis. Surgery should be conducted for selected patients.

3.
Clin Neurol Neurosurg ; 239: 108246, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38507988

RESUMO

BACKGROUND: Traumatic subdural effusion (TSDE) may increase progressively or evolve into chronic subdural hematoma. These events, defined as deterioration of the effusion, often require close observation or even surgical treatment. The aim of our study was to develop and validate a nomogram for predicting the possibility of an effusion deteriorating in patients with TSDE based on the available clinical characteristics. METHODS: Clinical data from 78 patients with TSDE were retrospectively analyzed. All patients were admitted from January 2019 to May 2022. Logistic regression was applied to the data to screen for independent predictors of effusion deterioration within six months; then, a predictive nomogram model was established in R language. The consistency, predictive accuracy and clinical utility of the model were evaluated with the C-index, calibration plots, ROC curves and decision curve analysis (DCA). Furthermore, we performed internal validation using a bootstrap approach to assess the effectiveness of the model. RESULTS: Time of effusion after trauma, maximum thickness of the effusion, CT value of the effusion as well as the use of atorvastatin were identified as predictors in the nomogram. The predictive model was well calibrated and demonstrated good discrimination (C-index: 0.893). The AUC of the model was 0.893 (95% CI: 0.824-0.962), and the modified C-index (0.865) indicated excellent performance in the internal validation. In addition, DCA revealed that the nomogram had clinical value. CONCLUSIONS: This predictive model can effectively assess the risk of effusion deterioration in TSDE patients within six months and identify high-risk patients early.


Assuntos
Líquidos Corporais , Derrame Subdural , Humanos , Nomogramas , Estudos Retrospectivos , Atorvastatina
4.
Neurochem Int ; 174: 105696, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38354751

RESUMO

Brain-related complications are common in clinical practice after spinal cord injury (SCI); however, the molecular mechanisms of these complications are still unclear. Here, we reviewed the changes in the brain regions caused by SCI from three perspectives: imaging, molecular analysis, and electrophysiology. Imaging studies revealed abnormal functional connectivity, gray matter volume atrophy, and metabolic abnormalities in brain regions after SCI, leading to changes in the structure and function of brain regions. At the molecular level, chemokines, inflammatory factors, and damage-associated molecular patterns produced in the injured area were retrogradely transmitted through the corticospinal tract, cerebrospinal fluid, or blood circulation to the specific brain area to cause pathologic changes. Electrophysiologic recordings also suggested abnormal changes in brain electrical activity after SCI. Transcranial magnetic stimulation, transcranial direct current stimulation, and deep brain stimulation alleviated pain and improved motor function in patients with SCI; therefore, transcranial therapy may be a new strategy for the treatment of patients with SCI.


Assuntos
Traumatismos da Medula Espinal , Estimulação Transcraniana por Corrente Contínua , Humanos , Encéfalo/patologia , Traumatismos da Medula Espinal/terapia , Traumatismos da Medula Espinal/patologia , Substância Cinzenta/patologia , Tratos Piramidais/patologia , Medula Espinal/patologia
6.
Food Chem X ; 20: 100928, 2023 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-38144734

RESUMO

A one-pot extraction-assisted d-galactose-to-d-tagatose isomerization strategy was proposed based on the selective extraction of d-tagatose by phenylborate anions. 4-Vinylphenylboronic acid was selected with high extraction efficiency and selectivity towards d-tagatose. The extracted sugars could be desorbed through a two-staged stripping process with the purity of d-tagatose significantly increased. In-situ extraction-assisted d-galactose-to-d-tagatose isomerization was implemented for the first time ever reported, and the effect of boron-to-sugar ratio (boron: sugar) was investigated. The conversion yield of d-tagatose at 60 °C increased from âˆ¼ 39 % (boron: sugar = 0.5) to âˆ¼ 56 % (boron: sugar = 1) but then decreased to âˆ¼ 44 % (boron: sugar = 1.5). With temperature increased to 70 °C, the conversion yield of d-tagatose was further improved to âˆ¼ 61 % (boron: sugar = 1.5), with the minimized formation of byproducts. Moreover, high purity (∼83 %) and concentrated d-tagatose solution (∼40 g/L) was obtained after sequential desorption. The proposed extraction-assisted isomerization strategy achieved improving the yield and purity of d-tagatose, proving its feasibility in industrial applications.

7.
Health Sci Rep ; 6(11): e1686, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37936615

RESUMO

Background and Aims: The Coronavirus Disease-19 (COVID-19) is posing an ongoing threat to human health. Patients of diabetic foot ulcer (DFU) are susceptible to COVID-19-induced adverse outcomes. Nevertheless, investigations into their mutual molecular mechanisms have been limited to date. In the present work, we tried to uncover the shared pathogenesis and regulatory gene targets of COVID-19 and DFU. Methods: In this study, we chose GSE161281 as the COVID-19 data set, which contained severe acute respiratory syndrome coronavirus 2 infected human induced embryonic stem cell-derived peripheral neurons (n = 2) with uninfected controls (n = 2). The GSE134431 designated as the DFU data set, comprising full-thickness DFU (n = 13) and diabetic foot skin (n = 8) samples from diabetic patients. The differential expressed genes (DEGs) were identified from GSE161281 and GSE134431, and the common DEGs between COVID-19 and DFU were extracted. Multifactor regulatory network and co-expression network of the common DEGs were analyzed, along with candidate drug prediction. Results: Altogether, six common DEGs (dickkopf-related protein 1 [DKK1], serine proteinase inhibitor A3 [SERPINA3], ras homolog family member D [RHOD], myelin protein zero like 3 [MPZL3], Claudin-11 [CLDN11], and epidermal growth factor receptor pathway substrate 8-like 1 [EPS8L1]) were found between COVID-19 and DFU. Functional analyses indicated that pathways of apoptotic and Wnt signaling may contribute to progression of COVID-19. Gene co-expression network implied the shared pathways of immune regulation and cytokine response participated collectively in the development of DFU and COVID-19. A multifactor regulatory network was constructed integrating the corresponding microRNAs (miRNAs) and transcription factors. Additionally, we proposed potential drug objects for the combined therapy. Conclusion: Our study revealed the shared molecular mechanisms underlying COVID-19 and DFU. The identified pivotal targets and common pathways can provide new perspectives for further research and assist the development of management strategies in patients of DFU complicated with COVID-19.

8.
J Sci Food Agric ; 2023 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-37997448

RESUMO

BACKGROUND: Developing the stable and healthy emulsion-based food is in accord with the needs of people for health. In the present study, acidification at pH 3.0 of peanut polysaccharide (APPSI) was employed to regulate its conformation and further improve its advantages in preparing oil-in-water emulsion. RESULTS: The results indicated that acidification induced conversion of PPSI aggregates into linear chains. Increasing concentration promoted formation of cross-linked network structure shown in transmission electron microscopy images. Consequently, the viscosity, yield stress, storage modulus and flow activation energy significantly increased, further fabricating gel structure. Moreover, aggregation behavior suggested that more exposed proteins were involved in gel structure, thereby forming many hydrophobic cores as verified by fluorescence spectroscopy of pyrene. Afterwards, emulsion characteristics indicated that APPSI produced strong and thick steric hindrance around oil droplets and the coil-like interweaved chains locked the continuous phase, bringing strong elasticity and resistance to stress and creaming. Meanwhile, the lower fatty acid in APPSI-emulsion was released after simulated gastrointestinal digestion, mainly as a result of the high retention ratio of emulsion droplets. Furthermore, the elastic and viscous Lissajous curves suggested that the structure strength of APPSI-emulsion was similar to that of the salad dressing within the strain 53.22%. CONCLUSION: The conformation of PPSI after acidification at pH 3.0 was suitable for preparing the stable emulsion. The obtained emulsion could resist digestion and maintain a strong structure, comprising a cholesterol-free and low-fat salad dressing substitute. © 2023 Society of Chemical Industry.

9.
Int J Biol Macromol ; 253(Pt 4): 127093, 2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-37758108

RESUMO

Promiscuous enzymes play a crucial role in organism survival and new reaction mining. However, comprehensive mapping of the catalytic and regulatory mechanisms hasn't been well studied due to the characteristic complexity. The cellobiose 2-epimerase from Caldicellulosiruptor saccharolyticus (CsCE) with complex epimerization and isomerization was chosen to comprehensively investigate the promiscuous mechanisms. Here, the catalytic frame of ring-opening, cis-enediol mediated catalysis and ring-closing was firstly determined. To map the full view of promiscuous CE, the structure of CsCE complex with the isomerized product glucopyranosyl-ß1,4-fructose was determined. Combined with computational calculation, the promiscuity was proved a precise cooperation of the double subsites, loop rearrangement, and intermediate swaying. The flexible loop was like a gear, whose structural reshaping regulates the sway of the intermediates between the two subsites of H377-H188 and H377-H247, and thus regulates the catalytic directions. The different protonated states of cis-enediol intermediate catalyzed by H188 were the key point for the catalysis. The promiscuous enzyme tends to utilize all elements at hand to carry out the promiscuous functions.


Assuntos
Celobiose , Racemases e Epimerases , Celobiose/química , Catálise , Especificidade por Substrato
10.
Food Chem ; 429: 136935, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37499512

RESUMO

High-purity lactulose is mandatory for its medical uses and food applications. This work developed an efficient lab-scale strategy for the synthesis of high-purity lactulose by combining lactose-to-lactulose isomerization with simultaneous recovery of lactulose, which was conducted concurrently and semi-continuously in a boronate affinity adsorbent-packed column. The first step covers the boronate affinity adsorbent-based adsorption-assisted lactose-to-lactulose isomerization. Under optimized conditions, in situ selectively binding of the newly formed lactulose onto the boronate affinity adsorbent enables a much-enhanced lactulose yield up to 80.20% with the lowest byproducts yield of 6.30%. Afterward, over 90% of the adsorbed lactulose can be recovered through sequential desorption with purity >98%. The net outcome of the applied strategy was the yield of high-purity lactulose up to 72.31%, the highest value ever reported. Moreover, the packed column displayed excellent operational stability. The encouraging results validate the high potential of this approach in the sustainable production of high-purity lactulose.


Assuntos
Lactose , Lactulose , Lactose/metabolismo , Adsorção , Isomerismo , Alimentos
11.
J Sci Food Agric ; 103(14): 7006-7020, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37319237

RESUMO

BACKGROUND: Recovery of high-purity tea saponin (TS), a promising non-ionic surfactant with well-documented properties, is one of the major challenges to broadening its industrial applications. In this study, an innovative and sustainable strategy for the highly-efficient purification of TS was developed by using well-designed highly-porous polymeric adsorbents. RESULTS: The prepared Pp-A with controllable macropores (~96 nm) and appropriate surface hydrophobic properties was found more favorable for achieving high adsorption efficiency towards TS/TS-micelles. Kinetic results showed the adsorption follows the pseudo-second-order model (R2 = 0.9800), and the Langmuir model is more qualified to explicate the adsorption isotherms with Qe-TS ~ 675 mg g-1 . Thermodynamic studies revealed the monolayer adsorption of TS was an endothermic process that was conducted spontaneously. Interestingly, ethanol-driven desorption (90% v/v ethanol) of TS was rapidly (< 30 min) complete due to the possible ethanol-mediated disassembling of TS-micelles. A possible mechanism that involves the interactions between the adsorbents and TS/TS-micelles, the formation and disassembling of TS-micelles was proposed to account for the highly efficient purification of TS. Afterwards, Pp-A-based adsorption method was developed to purify TS directly from industrial camellia oil production. Through selective adsorption, pre-washing, and ethanol-driven desorption, the applied Pp-A enabled the direct isolation of high-purity TS (~96%) with a recovery ratio > 90%. Notably, Pp-A exhibited excellent operational stability and is of high potential for long-term industrial application. CONCLUSION: Results ensured the practical feasibility of the prepared porous adsorbents in purifying TS, and the proposed methodology is a promising industrial-scale purification strategy. © 2023 Society of Chemical Industry.


Assuntos
Camellia , Saponinas , Poluentes Químicos da Água , Purificação da Água , Camellia/química , Porosidade , Micelas , Polímeros , Adsorção , Chá/química , Etanol , Cinética , Poluentes Químicos da Água/química , Purificação da Água/métodos
12.
Heliyon ; 9(6): e16996, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37342577

RESUMO

The pathogenesis and progression of GBM (glioblastoma), as one of the most frequently occurring malignancies of the central nervous system, are regulated by several genes. BUB1 (budding uninhibited by benzimidazoles 1) is a mitotic checkpoint that plays an important role in chromosome segregation as well as in various tumors. However, its role in glioma is unknown. The current study discovered prominently elevated BUB1 in glioma and a significant relationship between BUB1 expression, a high World Health Organization grade, and a poor prognosis in glioma patients. Moreover, BUB1 triggered EMT (epithelial-mesenchymal transition) apart from promoting glioma cell proliferation, migration, and infiltration. Besides, BUB1 promoted EMT by activating the Wnt/ß-catenin axis. As implied by our study, BUB1 probably has the potential as a target for GBM management.

13.
J Cell Biol ; 222(7)2023 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-37102997

RESUMO

Homotypic membrane fusion catalyzed by the atlastin (ATL) GTPase sustains the branched endoplasmic reticulum (ER) network in metazoans. Our recent discovery that two of the three human ATL paralogs (ATL1/2) are C-terminally autoinhibited implied that relief of autoinhibition would be integral to the ATL fusion mechanism. An alternative hypothesis is that the third paralog ATL3 promotes constitutive ER fusion with relief of ATL1/2 autoinhibition used conditionally. However, published studies suggest ATL3 is a weak fusogen at best. Contrary to expectations, we demonstrate here that purified human ATL3 catalyzes efficient membrane fusion in vitro and is sufficient to sustain the ER network in triple knockout cells. Strikingly, ATL3 lacks any detectable C-terminal autoinhibition, like the invertebrate Drosophila ATL ortholog. Phylogenetic analysis of ATL C-termini indicates that C-terminal autoinhibition is a recent evolutionary innovation. We suggest that ATL3 is a constitutive ER fusion catalyst and that ATL1/2 autoinhibition likely evolved in vertebrates as a means of upregulating ER fusion activity on demand.


Assuntos
GTP Fosfo-Hidrolases , Fusão de Membrana , Animais , Humanos , Drosophila , GTP Fosfo-Hidrolases/genética , Filogenia
14.
BMC Infect Dis ; 23(1): 245, 2023 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-37072710

RESUMO

BACKGROUND: Balamuthia granulomatous amoebic encephalitis (GAE) is a peculiar parasitic infectious disease of the central nervous system, about 39% of the infected Balamuthia GAE patients were found to be immunocompromised and is extremely rare clinically. The presence of trophozoites in diseased tissue is an important basis for pathological diagnosis of GAE. Balamuthia GAE is a rare and highly fatal infection for which there is no effective treatment plan in clinical practice. CASE PRESENTATION: This paper reports clinical data from a patient with Balamuthia GAE to improve physician understanding of the disease and diagnostic accuracy of imaging and reduce misdiagnosis. A 61-year-old male poultry farmer presented with moderate swelling pain in the right frontoparietal region without obvious inducement three weeks ago. Head computed tomography(CT) and magnetic resonance imaging(MRI) revealed a space-occupying lesion in the right frontal lobe. Intially clinical imaging diagnosed it as a high-grade astrocytoma. The pathological diagnosis of the lesion was inflammatory granulomatous lesions with extensive necrosis, suggesting amoeba infection. The pathogen detected by metagenomic next-generation sequencing (mNGS) is Balamuthia mandrillaris, the final pathological diagnosis was Balamuthia GAE. CONCLUSION: When a head MRI shows irregular or annular enhancement, clinicians should not blindly diagnose common diseases such as brain tumors. Although Balamuthia GAE accounts for only a small proportion of intracranial infections, it should be considered in the differential diagnosis.


Assuntos
Amebíase , Infecções Parasitárias do Sistema Nervoso Central , Infecções Protozoárias do Sistema Nervoso Central , Encefalite , Encefalite Infecciosa , Masculino , Humanos , Pessoa de Meia-Idade , Encefalite/diagnóstico , Infecções Protozoárias do Sistema Nervoso Central/diagnóstico , Infecções Protozoárias do Sistema Nervoso Central/parasitologia , Amebíase/diagnóstico , Amebíase/parasitologia , Amebíase/patologia , Encéfalo/patologia , Infecções Parasitárias do Sistema Nervoso Central/patologia , Granuloma/patologia , Evolução Fatal
15.
Int J Biol Macromol ; 235: 123739, 2023 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-36806768

RESUMO

Bacterial cellulose (BC) with good biocompatibility and superior mechanical properties has broad applications. BC functionalized with silver nanoparticles (AgNPs) has been assessed as an antimicrobial membrane for wound-healing treatment. During the AgNPs synthesis, avoiding the use of toxic chemicals is very necessary for the development of environmentally friendly procedures. Herein, a Komagataeibacter xylinus-based direct biosynthetic method to fabricate D-Saccharic acid potassium salt (SA)-grafted BC (SABC) through in situ bacterial metabolism was firstly explored. Subsequently, the SABC pellicles were immersed in AgNO3 solution for ion-exchanged process, and the silver nanoparticles (AgNPs) with diameter of ∼25.2 nm were in situ synthesized on SABC nanofiber surfaces by thermal reduction instead of using a reducing agent. The morphology and microstructure of SABC/AgNPs pellicles were analyzed by field-emission scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction, and X-ray photoelectron spectra. Moreover, antibacterial activity measurement performed against the Gram-negative Escherichia coli (E. coli) and Gram-positive Staphylococcus aureus (S. aureus) by disk diffusion and plate count methods, showed high-efficiency bacteria-killing performance of SABC/AgNPs pellicles. This work proposed a new method by using microbial metabolism to prepare BC pellicles with functional groups, and antimicrobial films containing AgNPs was prepared by thermal reduction, exhibiting valuable prospects in wound healing treatment.


Assuntos
Anti-Infecciosos , Nanopartículas Metálicas , Prata/farmacologia , Prata/química , Celulose/química , Staphylococcus aureus , Nanopartículas Metálicas/química , Escherichia coli , Antibacterianos/farmacologia , Antibacterianos/química , Bactérias , Espectroscopia de Infravermelho com Transformada de Fourier , Testes de Sensibilidade Microbiana , Difração de Raios X
16.
ACS Appl Mater Interfaces ; 15(5): 6514-6525, 2023 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-36695173

RESUMO

The increasing spread of antibiotic resistance in bacterial pathogens poses a huge threat to global human health. Precise targeting of bacterial pathogens while avoiding collateral damage to healthy tissues has become the overriding goal for bacterial infection treatment. Inspired by the host specificity of bacteriophages, a biomimetic intelligent platform was designed for highly precise photothermal treatment herein. As proof-of-concept, the lysin cell-binding domain (CBD) from a newly discovered virulent methicillin-resistant S. aureus (MRSA) phage Z was applied to the functionalization of gold nanosheets. Our results demonstrated that the bionanocomposite gold particles (Au@PEG-CBDz) could be effectively delivered directly to MRSA and kill them effectively under near infrared irradiation in vitro, while displaying good in vivo biocompatibility. This work is the first to report the combination of phage lysin navigatory function with photothermal effect-induced bactericidal activity from Au nanosheets, providing a novel therapeutic mode for the precision treatment of antibiotic-resistant bacterial infections.


Assuntos
Bacteriófagos , Staphylococcus aureus Resistente à Meticilina , Infecções Estafilocócicas , Humanos , Meticilina/farmacologia , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Resistência a Meticilina , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/microbiologia , Ouro/química
17.
Food Chem ; 403: 134367, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36358067

RESUMO

A pulsed electric field (PEF) induces cell electroporation for solid foods, thereby allowing PEF to be used as a pretreatment method for extraction, drying, peeling, freeze-thawing, and cooking by increasing mass transfer. Currently, popular research mainly focuses on the process and results of the application of PEF to solid food processing. Therefore, this review summarizes the impact of PEF on the quality of solid food, the evaluation techniques of PEF-treated tissues and the characteristics of PEF treatment chambers. Furthermore, other pretreatments, including freezing and peeling, typically used in the meat and vegetable sectors, are also discussed alongside PEF to evaluate the impact on its effects. Finally, this article examined the main obstacles and prospects of PEF in solid food processing. This evaluation is anticipated to expand future PEF research paths in the solid food industry.


Assuntos
Eletricidade , Manipulação de Alimentos , Manipulação de Alimentos/métodos , Indústria de Processamento de Alimentos , Carne/análise , Tecnologia
18.
J Agric Food Chem ; 70(50): 15879-15893, 2022 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-36475670

RESUMO

Enzymatic isomerization of lactose into lactulose via cellobiose 2-epimerase (CE) could provide an eco-friendly route for the industrial production of lactulose, a valuable food prebiotic. However, poor substrate affinity for lactose and preference for epimerization over isomerization hinder this application. Previous studies on CE improvement have focused on random mutagenesis or active site rational design; little is known about the relationship between substrate binding and enzyme efficacy, which was hence the subject of this study. First, residues 372W and 308W were identified as key for disaccharide recognition in CEs based on crystal structure alignment of the N-acetyl-glucosamine 2-epimerase superfamily and site-directed mutation. This binding domain was then reshaped through site saturation mutagenesis, resulting in seven mutants with enhanced isomerization activity. The optimal mutant CsCE/Q371E had significantly enhanced substrate affinity (Km, 269.65 mM vs Km, 417.5 mM), reduced epimerization activity, and 3.3-fold increased isomerization activity over the original CsCE. Molecular dynamics simulation further revealed that substituting Gln-371 with Glu strengthened the hydrogen-bonding network and altered the active site-substrate interactions, increasing the substrate stability and shifting the catalytic direction. This study uncovered new information about the substrate binding region and its mechanisms and impact on CE catalytic performance, paving the way for potential commercial applications.


Assuntos
Celobiose , Lactulose , Lactulose/química , Celobiose/metabolismo , Lactose/química , Isomerismo , Racemases e Epimerases/genética , Racemases e Epimerases/metabolismo , Especificidade por Substrato
19.
Front Surg ; 9: 995986, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36329982

RESUMO

Primary intraosseous meningiomas (PIOMs) are a rare subset of meningiomas, comprising fewer than 1% of all such tumors. Furthermore, PIOMs presenting as osteogenic lesions that invade both the dura and subcutaneous tissue are extremely rare. Unlike intracranial meningiomas, diagnosing and treating PIOMs are challenges due to their insidious clinical behavior and a lack of clear radiological diagnostic criteria. We report the case of a 60-year-old female with headache and a slightly outward protrusion of the parietal region of the skull. CT showed an osteogenic lesion in the right parietal bone. MR imaging indicated mild to moderate homogeneous enhancement with an intense dural reaction. The suggested clinical diagnosis was lymphoma, so we performed a skull biopsy, which revealed an intraosseous benign meningioma. A precise resection strategy was planned with a neuronavigation system accompanied by a one-step customized titanium mesh cranioplasty. The lesion was completely removed, and pathological analysis confirmed a meningothelial meningioma (WHO Grade I) of intraosseous layer origin invading the dura mater and subcutaneous tissue. This case highlights the need for an initial biopsy when the lesion is difficult to diagnose on imaging. Complete resection should be attempted to minimize the risk of recurrence.

20.
Mol Nutr Food Res ; 66(20): e2200171, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36109175

RESUMO

Xylo-oligosaccharides (XOS) has a bidirectional regulatory effect, and can be fermented by gut microbiota. This study aims to investigate how XOS alleviates Folium Sennae extracts induced diarrhea in mice. KM mice are given different concentration XOS for 3 weeks, and then Folium Sennae (Senna alexandrina Mill) extracts solutions (0.8 g mL-1 ) are given to establish diarrhea model. The results show that doses of XOS at 0.25 mg g-1 BW day-1 and higher could alleviate diarrhea symptoms by decreasing the disease activity indexes, down-regulating pro-inflammatory factors, up-regulating anti-inflammatory factor, and suppressing the intestinal permeability in colon tissues. XOS also regulates the composition of gut microbiota via increasing the abundance Prevotellaceae, Ruminococcus, and Bifidobacterium. The results suggest that the dietary supplementation XOS could be a more effective choice to prevent and alleviate diarrhea.


Assuntos
Microbioma Gastrointestinal , Camundongos , Animais , Prebióticos , Oligossacarídeos/farmacologia , Intestinos/microbiologia , Diarreia/tratamento farmacológico
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