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1.
Nucleic Acids Res ; 51(13): 6870-6882, 2023 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-37283056

RESUMO

Actinobacteria are ubiquitous bacteria undergoing complex developmental transitions coinciding with antibiotic production in response to stress or nutrient starvation. This transition is mainly controlled by the interaction between the second messenger c-di-GMP and the master repressor BldD. To date, the upstream factors and the global signal networks that regulate these intriguing cell biological processes remain unknown. In Saccharopolyspora erythraea, we found that acetyl phosphate (AcP) accumulation resulting from environmental nitrogen stress participated in the regulation of BldD activity through cooperation with c-di-GMP. AcP-induced acetylation of BldD at K11 caused the BldD dimer to fall apart and dissociate from the target DNA and disrupted the signal transduction of c-di-GMP, thus governing both developmental transition and antibiotic production. Additionally, practical mutation of BldDK11R bypassing acetylation regulation could enhance the positive effect of BldD on antibiotic production. The study of AcP-dependent acetylation is usually confined to the control of enzyme activity. Our finding represents an entirely different role of the covalent modification caused by AcP, which integrated with c-di-GMP signal in modulating the activity of BldD for development and antibiotic production, coping with environmental stress. This coherent regulatory network might be widespread across actinobacteria, thus has broad implications.


Assuntos
Antibacterianos , Saccharopolyspora , Antibacterianos/biossíntese , Proteínas de Bactérias/metabolismo , GMP Cíclico/metabolismo , Regulação Bacteriana da Expressão Gênica , Saccharopolyspora/metabolismo
2.
Mol Microbiol ; 119(2): 151-160, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36349384

RESUMO

Actinobacteria have a complex life cycle, including morphological and physiological differentiation which are often associated with the biosynthesis of secondary metabolites. Recently, increased interest in post-translational modifications (PTMs) in these Gram-positive bacteria has highlighted the importance of PTMs as signals that provide functional diversity and regulation by modifying proteins to respond to diverse stimuli. Here, we review the developments in research on acylation, a typical PTM that uses acyl-CoA or related metabolites as donors, as well as the understanding of the direct link provided by acylation between cell metabolism and signal transduction, transcriptional regulation, cell growth, and pathogenicity in Actinobacteria.


Assuntos
Actinobacteria , Virulência , Transdução de Sinais , Acilação , Proteínas , Processamento de Proteína Pós-Traducional
3.
Chemistry ; 30(18): e202303919, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38263478

RESUMO

Encouraged by the successful fabrication of C60-GNR (GNR=graphene nanoribbon) single-molecule transistors in experiments, four Fe-containing derived double-layered devices of Fe@C60-GNR are designed by employing different electrode linkages and their transport properties are investigated by using density functional theory (DFT) and nonequilibrium Green's function (NEGF) methods. Regardless of electrode connection, all these devices give rise to a smaller negative differential resistance (NDR) peak at V=0.2 and a higher peak at 1.2 V, suggesting their stable maneuverability as molecular devices and good candidates for developing on(off)-off(on)-on(off) current switches. The macroscopic NDR performance depends on the delocalization character and the crossing mechanism of the frontier orbitals. The peak-to-valley current ratios (Rmax) range from 454 to 2737, determined by the electrode linkage. Such a large Rmax-value is necessary for developing dynamic random-access memory (DRAM) cells. Encapsulating the Fe atom inside C60 not only improves the conductivity but also introduces the spin-polarized transport property. The spin-filtering efficiency (SFE) of almost all devices oscillates up and down in response to the bias voltage, indicating the possibility of designing on(off)-off(on)-on(off) spin switches and up-down spin switches. All these fascinating properties provide an important clue for designing similar molecular devices with multiple functions by trapping magnetic transition metal atoms inside fullerenes.

4.
J Hepatol ; 79(2): 394-402, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37086919

RESUMO

BACKGROUND & AIMS: Ischemia-reperfusion injury (IRI) has thus far been considered as an inevitable component of organ transplantation, compromising outcomes, and limiting organ availability. Ischemia-free organ transplantation is a novel approach designed to avoid IRI, with the potential to improve outcomes. METHODS: In this randomized-controlled clinical trial, recipients of livers from donors after brain death were randomly assigned to receive either an ischemia-free or a 'conventional' transplant. The primary endpoint was the incidence of early allograft dysfunction. Secondary endpoints included complications related to graft IRI. RESULTS: Out of 68 randomized patients, 65 underwent transplants and were included in the analysis. 32 patients received ischemia-free liver transplantation (IFLT), and 33 received conventional liver transplantation (CLT). Early allograft dysfunction occurred in two recipients (6%) randomized to IFLT and in eight (24%) randomized to CLT (difference -18%; 95% CI -35% to -1%; p = 0.044). Post-reperfusion syndrome occurred in three recipients (9%) randomized to IFLT and in 21 (64%) randomized to CLT (difference -54%; 95% CI -74% to -35%; p <0.001). Non-anastomotic biliary strictures diagnosed with protocol magnetic resonance cholangiopancreatography at 12 months were observed in two recipients (8%) randomized to IFLT and in nine (36%) randomized to CLT (difference, -28%; 95% CI -50% to -7%; p = 0.014). The comprehensive complication index at 1 year after transplantation was 30.48 (95% CI 23.25-37.71) in the IFLT group vs. 42.14 (95% CI 35.01-49.26) in the CLT group (difference -11.66; 95% CI -21.81 to -1.51; p = 0.025). CONCLUSIONS: Among patients with end-stage liver disease, IFLT significantly reduced complications related to IRI compared to a conventional approach. CLINICAL TRIAL REGISTRATION: chictr.org. ChiCTR1900021158. IMPACT AND IMPLICATIONS: Ischemia-reperfusion injury has thus far been considered as an inevitable event in organ transplantation, compromising outcomes and limiting organ availability. Ischemia-free liver transplantation is a novel approach of transplanting donor livers without interruption of blood supply. We showed that in patients with end-stage liver disease, ischemia-free liver transplantation, compared with a conventional approach, led to reduced complications related to ischemia-reperfusion injury in this randomized trial. This new approach is expected to change the current practice in organ transplantation, improving transplant outcomes, increasing organ utilization, while providing a clinical model to delineate the impact of organ injury on alloimmunity.


Assuntos
Doença Hepática Terminal , Transplante de Fígado , Traumatismo por Reperfusão , Humanos , Transplante de Fígado/efeitos adversos , Transplante de Fígado/métodos , Doença Hepática Terminal/complicações , Isquemia/patologia , Fígado/patologia , Traumatismo por Reperfusão/etiologia , Traumatismo por Reperfusão/prevenção & controle , Traumatismo por Reperfusão/patologia , Perfusão/métodos , Preservação de Órgãos/métodos
5.
Mol Pharm ; 19(11): 3877-3883, 2022 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-36018674

RESUMO

The innovation of cancer immunotherapy is improving the prognosis of colorectal cancer (CRC) in clinics. Nevertheless, due to tumor heterogeneity and complex underlying inhibitory mechanisms, the therapeutic response greatly varies among different patients. To optimize the clinical management of CRC patients, it is critical to develop novel approaches for response monitoring and prediction. In the current study, we developed a novel near-infrared fluorescence (NIRF) imaging probe (Cy5.5-ICOS mAb) targeting the inducible T-cell costimulatory receptor (ICOS or CD278) and assessed its capacity for the detection of ICOS+-activated T cells in vivo. ICOS expression was evaluated by flow cytometry and immunofluorescence staining in subcutaneous MC38 models treated with the stimulator of interferon genes (STING) agonist (STINGa). NIRF imaging study was performed 1 day after the last treatment, and tumor volume was monitored every other day with a caliper. A significantly higher optical signal could be detected at tumor regions in STINGa group, compared with that in the PBS group at all time points imaged, and this was in line with ex vivo imaging and immunofluorescence staining study. The data demonstrated that Cy5.5-ICOS mAb could detect ICOS+-activated T cells with high specificity, and ICOS NIRF imaging is a promising strategy for predicting and monitoring immune response in CRC.


Assuntos
Neoplasias Colorretais , Imunoterapia , Humanos , Carbocianinas , Imunoterapia/métodos , Diagnóstico por Imagem , Corantes Fluorescentes , Neoplasias Colorretais/diagnóstico por imagem , Neoplasias Colorretais/tratamento farmacológico
6.
BMC Surg ; 22(1): 356, 2022 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-36195942

RESUMO

BACKGROUND: Fractures of the lateral process of the talus (LTPF) are rare and only rarely are associated ligamentous injuries. The injury mechanism is commonly considered to be similar with ankle sprains, where excessive varus of the hindfoot leads to avulsion fractures of the lateral process of the talus. However, previous cadaveric studies have suggested that LTPF was more likely to be caused by eversion or external rotation force with dorsiflexion of the ankle. But no clinical evidence has been provided. CASE PRESENTATION: Two patients presented to the emergency department with ankle pain after ankle eversion or external rotation. Physical examination revealed tenderness and swelling on both medial and lateral sides of the ankles. Plain radiographs and computed tomography revealed LTPF and medial soft tissue swelling, and magnetic resonance imaging confirmed a discontinuity of the deltoid ligament in Case 1. Surgical exploration revealed rupture of the superficial layer of the deltoid ligaments with intact deep layer in both patients. Treatment included fixation of the lateral process of the talus with headless compression screws and repair of deltoid ligaments. Both patients achieved excellent clinical outcomes 1 year post injury. CONCLUSION: There are many possibilities of the injury mechanism of LTPF. These two cases provided clinical evidence that eversion or external rotation force, in addition to inversion, was also an important mechanism of LTPF.


Assuntos
Traumatismos do Tornozelo , Fraturas Ósseas , Tálus , Adulto , Traumatismos do Tornozelo/complicações , Traumatismos do Tornozelo/diagnóstico por imagem , Traumatismos do Tornozelo/cirurgia , Articulação do Tornozelo/cirurgia , Fraturas Ósseas/complicações , Fraturas Ósseas/diagnóstico por imagem , Fraturas Ósseas/cirurgia , Humanos , Ligamentos Articulares/diagnóstico por imagem , Ligamentos Articulares/lesões , Ligamentos Articulares/cirurgia , Masculino , Tálus/diagnóstico por imagem
7.
Med Sci Monit ; 26: e922598, 2020 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-32772042

RESUMO

BACKGROUND For proximal humeral fractures (PHFs), locking intramedullary nails and locking plates have been widely used. However, few reports have been published on the therapy of complex PHFs accompanying humeral shaft fractures. Therefore, we performed this research to analyze the effectiveness of locking intramedullary nails and locking plates in the management of proximal humeral fractures involving the humeral shaft. MATERIAL AND METHODS We retrospectively reviewed 40 cases diagnosed with proximal humeral fractures involving the humeral shaft fixed with either locking intramedullary nails or locking plates with at least of 2 years' follow-up. Clinical data were obtained from the medical records. Follow-up data included the Constant-Murley score, American Shoulder and Elbow Surgeons score (ASES), visual analog scale score (VAS), and the relative strength of the supraspinatus and deltoid muscles. RESULTS In total, 19 locking plate patients and 21 locking intramedullary nail patients were analyzed. The average follow-up period was 35 months in the locking plate group and 34 months in the locking intramedullary nail group. There were obvious differences in the intraoperative blood loss, time of operation, and the length of operative incision between the 2 groups (p<0.05). There were no significant differences between the groups in Constant-Murley score, ASES, VAS, or the relative strength of supraspinatus and deltoid muscles. CONCLUSIONS For PHFs involving the humeral shaft, both locking plates and locking intramedullary nails can achieve satisfactory functional results in the long-term follow-up assessment. The locking intramedullary nail group was superior with regards to intraoperative blood loss, time of operation, and length of incision.


Assuntos
Pinos Ortopédicos , Fixação Intramedular de Fraturas/métodos , Fraturas do Ombro/cirurgia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/fisiopatologia , Estudos Retrospectivos , Fraturas do Ombro/reabilitação
8.
BMC Surg ; 20(1): 71, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32293417

RESUMO

BACKGROUND: Simultaneous dislocation of the radial head and distal radio-ulnar joint without fracture (Criss-Cross Injury) in an adult patient is rarely reported in previous studies. The pathological changes and injury patterns have not been clearly demonstrated. CASE PRESENTATION: A 26-year-old woman presented with acute pain of the right wrist and elbow after a fall from cycling. Physical examination revealed an unstable elbow and wrist joint. Plain radiographs showed volar dislocation of the radial head and dorsal dislocation of the distal radius without associated fracture, forming a criss-cross appearance of the ulna and radius on the lateral radiograph. MRI images confirmed partial rupture of the proximal interosseous membrane from its dorsal attachment on the radius, as well as partial rupture of the medial collateral ligament. Conservative treatment failed because the radiocapitellar joint and distal radio-ulnar joint could not be simultaneously reduced. Surgical exploration revealed a highly unstable radial head, but the annular ligament was found to be intact. Manual force was applied to reduce the radial head and a percutaneous K-wire was used to stabilize the proximal radioulnar joint with the forearm in full supination. After surgery, the elbow was immobilized in 90° flexion by a long arm cast for 4 weeks. The K-wire was removed at 6 weeks postoperatively. At 18 months postoperatively, the patient had regained a full range of flexion and extension, with normal supination and a slight limitation in pronation. CONCLUSIONS: The proximal IOM, especially the dorsal band, was injured in Criss-Cross injuries, while the central part of the IOM remained intact. This injury pattern distinguished itself from Essex-Lopresti injury, which mainly involves rupture of the central band of the IOM.


Assuntos
Articulação do Cotovelo/patologia , Luxações Articulares/cirurgia , Articulação do Punho/patologia , Adulto , Fios Ortopédicos , Feminino , Humanos , Radiografia , Rádio (Anatomia)/patologia , Amplitude de Movimento Articular , Ruptura , Ulna/patologia
9.
Acta Orthop Belg ; 85(3): 283-288, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31677623

RESUMO

We investigated the outcome of conservative treatment and potential causes for clavicle stress fractures following the clavicular hook plate fixation. Six cases of clavicle stress fractures were retrospectively reviewed. All the stress fractures occurred near the medial end of the hook plates. The average interval between the hook plate fixation and the clavicle stress fractures was 28.3 days (range, 18 to 60 days). The mean follow-up was 27 months (range, 15 to 42 months). Fracture union was achieved in all 6 cases. The most proximal screws in the hook plates were found to be eccentric in the clavicular midshaft in 5 cases. At the final follow-up, the average Constant and Murley scores of the operated shoulders were 91.7 (range, 83 to 96). Clavicle stress fractures could be treated conservatively with satisfactory results. Attention should be paid to the position of the most proximal screws in the hook plates.


Assuntos
Placas Ósseas/efeitos adversos , Clavícula/lesões , Fixação Interna de Fraturas/efeitos adversos , Fraturas de Estresse/etiologia , Adulto , Idoso , Clavícula/diagnóstico por imagem , Clavícula/cirurgia , Feminino , Fraturas de Estresse/diagnóstico por imagem , Fraturas de Estresse/terapia , Humanos , Masculino , Pessoa de Meia-Idade , Radiografia , Estudos Retrospectivos , Tomografia Computadorizada por Raios X
10.
Heliyon ; 10(9): e30197, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38756562

RESUMO

Purpose: This study aimed to explore the test-retest reliability of fNIRS in measuring frontal and parietal cortices activation during straight walking and turning walking in older adults, in order to provide a theoretical foundation for selecting assessment tools for clinical research on motor control and some diseases such as Parkinson's disease in older adults. Methods: 18 healthy older participants (69.1 ± 0.7 years) were included in this study. The participants completed straight walking and figure-of-eight turning walking tasks at self-selected speeds. Intra-class correlation coefficients (ICCs) and Bland-Altman scatter plots were used to assess the test-retest reliability of oxyhemoglobin (HbO2) changes derived from fNIRS. p < 0.05 was considered statistically significant. Results: The test-retest reliability of HbO2 in prefrontal cortex (ICC, 0.67-0.78) was good and excellent, in frontal motor cortex (ICC, 0.51-0.61) and parietal sensory cortex (ICC, 0.53-0.62) is fair and good when the older adults performed straight and turning walking tasks. Bland-Altman diagram shows that the data consistency is fair and good. Conclusion: fNIRS can be used as a clinical measurement method to evaluate the brain activation of the older adults when walking in a straight line and turning, and the results are acceptable repeatability and consistency. However, it is necessary to strictly control the testing process and consider the possible changes in the repeated measurements.

11.
Orthop Traumatol Surg Res ; 110(1): 103572, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36739963

RESUMO

INTRODUCTION: Fractures of the anterior process of the calcaneus (APC) are easily overlooked in clinical practice. Most patients have good to excellent clinical outcome after conservative treatment, while some patients may have persisting symptoms and unfavorable functional outcomes. The aim of this study was to identify the risk factors associated with unfavorable functional outcome after conservative treatment in APC fractures. METHODS: All patients presenting with APC fractures and receiving conservative treatment from April 2019 to April 2020 were retrospectively assessed. The primary outcome measurement was the ankle joint function assessed using Karlsson Scoring System at 2 years post-injury. The risk factors associated with unfavorable functional outcomes (Karlsson score ≤ 80) were evaluated by logistic regression analysis. RESULTS: In total, 84 patients were included with a mean age of 40 years. 26 (31%) patients presented with unfavorable functional outcome at 2 years post-injury. In multivariate logistic regression, concomitant fractures of talonavicular (TN) joints and older age were significantly associated with unfavorable functional outcome (p<0.05). Patients with concomitant fractures of TN joints had an odds ratio of 3.623 for unfavorable functional outcome. The optimal cutoff age for an unfavorable outcome was ≥ 47.5 years, with an odds ratio of 5.010. CONCLUSION: Most patients with APC fractures achieved good to excellent results when treated conservatively. Attention should be paid to those with concomitant fractures of TN joints and with age ≥ 47.5 years, which might lead to unfavorable functional recovery. LEVEL OF EVIDENCE: IV; case series.


Assuntos
Traumatismos do Tornozelo , Calcâneo , Traumatismos do Pé , Fraturas Ósseas , Traumatismos do Joelho , Humanos , Adulto , Pessoa de Meia-Idade , Calcâneo/diagnóstico por imagem , Calcâneo/lesões , Estudos Retrospectivos , Fixação Interna de Fraturas/métodos , Extremidade Inferior , Resultado do Tratamento
12.
Clin Mol Hepatol ; 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38600871

RESUMO

Background & Aims: The shortage of donor livers hinders the development of liver transplantations. This study aimed to clarify the poor outcomes of functioned marginal liver grafts (FMLs) and provide evidence for the improvement of ischemia-free liver transplantation (IFLT) on transplantation with FMLs. Methods: Propensity score matching was used to control for confounding factors. The outcomes of the control group and FMLs were compared to demonstrate the negative impact of FMLs in liver transplantation patients. We compared the clinical improvements of the different surgical types. To elucidate the underlying mechanism, we conducted bioinformatic analysis based on transcriptome and single-cell profiles. Results: FMLs showed a significantly higher Hazard Ratio (HR: 1.969, P = 0.018) than other marginal livers. A worse 90-days survival (12.3% vs. 5.0%, P = 0.007) was observed in patients who underwent FMLs. Patients receiving FMLs had a significant overall survival benefit after IFLT (10.4% vs. 31.3%, P = 0.006). Pyroptosis and inflammation are inhibited in patients who undergo IFLT. The infiltration of Natural Killer cells was lower in liver grafts from these patients. A positive relationship was observed between IL32 and Caspase 1 (R = 0.73, P = 0.01) and Gasdermin D (R = 0.84, P = 0.0012) in the bulk transcriptome profiles. Conclusion: FMLs function as a more important negative prognostic parameter than other marginal livers do. IFLT might ameliorate liver injury in FMLs by inhibiting the infiltration of NK cells, consequently leading to the abortion of IL-32, which drives pyroptosis in monocytes and macrophages.

13.
Anal Chim Acta ; 1311: 342720, 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38816155

RESUMO

BACKGROUND: The monkeypox virus (MPXV) is a linear double-stranded DNA virus with a large genome that causes tens of thousands of infections and hundreds of deaths in at least 40 countries and regions worldwide. Therefore, timely and accurate diagnostic testing could be an important measure to prevent the ongoing spread of MPXV and widespread epidemics. RESULTS: Here, we designed multiple sets of primers for the target region of MPXV for loop-mediated isothermal amplification (LAMP) detection and identified the optimal primer set. Then, the specificity in fluorescent LAMP detection was verified using the plasmids containing the target gene, pseudovirus and other DNA/RNA viruses. We also evaluated the sensitivity of the colorimetric LAMP detection system using the plasmid and pseudovirus samples, respectively. Besides, we used monkeypox pseudovirus to simulate real samples for detection. Subsequent to the establishment and introduction of a magnetic beads (MBs)-based nucleic acid extraction technique, an integrated device was developed, characterized by rapidity, high sensitivity, and remarkable specificity. This portable system demonstrated a visual detection limit of 137 copies/mL, achieving sample-to-answer detection within 1 h. SIGNIFICANCE: The device has the advantages of integration, simplicity, miniaturization, and visualization, which help promote the realization of accurate, rapid, portable, and low-cost testing. Meanwhile, this platform could facilitate efficient, cost-effective and easy-operable point-of-care testing (POCT) in diverse resource-limited settings in addition to the laboratory.


Assuntos
Colorimetria , Monkeypox virus , Técnicas de Amplificação de Ácido Nucleico , Colorimetria/métodos , Colorimetria/instrumentação , Técnicas de Amplificação de Ácido Nucleico/métodos , Monkeypox virus/genética , Monkeypox virus/isolamento & purificação , Limite de Detecção , Técnicas de Diagnóstico Molecular/métodos , Técnicas de Diagnóstico Molecular/instrumentação
14.
Front Physiol ; 14: 1153469, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37051020

RESUMO

Background: Neurological disorders with dyskinesia would seriously affect older people's daily activities, which is not only associated with the degeneration or injury of the musculoskeletal or the nervous system but also associated with complex linkage between them. This study aims to review the relationship between motor performance and cortical activity of typical older neurological disorder patients with dyskinesia during walking and balance tasks. Methods: Scopus, PubMed, and Web of Science databases were searched. Articles that described gait or balance performance and cortical activity of older Parkinson's disease (PD), multiple sclerosis, and stroke patients using functional near-infrared spectroscopy were screened by the reviewers. A total of 23 full-text articles were included for review, following an initial yield of 377 studies. Results: Participants were mostly PD patients, the prefrontal cortex was the favorite region of interest, and walking was the most popular test motor task, interventional studies were four. Seven studies used statistical methods to interpret the relationship between motor performance and cortical activation. The motor performance and cortical activation were simultaneously affected under difficult walking and balance task conditions. The concurrent changes of motor performance and cortical activation in reviewed studies contained the same direction change and different direction change. Conclusion: Most of the reviewed studies reported poor motor performance and increased cortical activation of PD, stroke and multiple sclerosis older patients. The external motor performance such as step speed were analyzed only. The design and results were not comprehensive and profound. More than 5 weeks walking training or physiotherapy can contribute to motor function promotion as well as cortices activation of PD and stroke patients. Thus, further study is needed for more statistical analysis on the relationship between motor performance and activation of the motor-related cortex. More different type and program sports training intervention studies are needed to perform.

15.
Front Microbiol ; 14: 1230775, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37637117

RESUMO

Phage contamination has become a major concern for industrial bacteria, such as Escherichia coli BL21(DE3), used in fermentation processes. Herein, we report a CRISPR/Cas9 defense system-based strategy to precisely prey and degrade phage DNA to decontaminate target phages. First, we isolated a novel phage from fermentation substrates with BL21(DE3) as the host, named TR1. It showed a typical podovirus morphology with a head diameter of 51.46 ± 2.04 nm and a tail length of 9.31 ± 2.77 nm. The burst size of phage TR1 was 151 PFU/cell, suggesting its strong fecundity in the fermentation system. Additionally, whole-genome sequencing revealed that phage TR1 has a DNA genome of 44,099 bp in length with a 43.8% GC content, encoding a total of 68 open reading frames. Comparative genomics and phylogenetic analysis designated this phage to be a new species of the genus Christensenvirus. To counteract phage TR1, we employed the CRISPR/Cas9 system-based strategy and constructed two phage-resistant E. coli strains, BL21-C and BL21-T, based on conserved genes. Both EOP assays and growth curves indicated strong phage resistance of the recombinant strains, without affecting cell growth. Therefore, this study aimed to provide a resilient strategy to respond to ever-changing phages and ongoing phage-host arm race in industrial fermentation environments by the personalized design of spacers in the recombinant CRISPR/Cas system-containing plasmid. More importantly, our research sparks the use of phage defense mechanism to prevent phage contamination in extensive biotechnological applications.

16.
Diabetes Metab Syndr Obes ; 16: 285-298, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36760596

RESUMO

Purpose: Delayed skin healing in diabetic wounds is a major clinical problem. The tRNA-derived small RNAs (tsRNAs) were reported to be associated with diabetes. However, the role of tsRNAs in diabetic wound healing is unclear. Our study was designed to explore the tsRNA expression profile and mine key potential tsRNAs and their mechanism in diabetic wounds. Methods: Skin tissues of patients with diabetic foot ulcers and healthy controls were subjected to small RNA sequencing. The role of candidate tsRNA was explored by loss- and gain-of-function experiments in HUVECs. Results: A total of 55 differentially expressed tsRNAs were identified, including 12 upregulated and 43 downregulated in the diabetes group compared with the control group. These tsRNAs were mainly concentrated in intercellular interactions and neural function regulation in GO terms and enriched in MAPK, insulin, FoxO, calcium, Ras, ErbB, Wnt, T cell receptor, and cGMP-PKG signaling pathways. tRF-Gly-CCC-039 expression was upregulated in vivo and in vitro in the diabetic model. High glucose disturbed endothelial function in HUVECs, and tRF-Gly-CCC-039 mimics further harmed HUVECs function, characterized by the suppression of proliferation, migration, tube formation, and the expression of Coll1a1, Coll4a2, and MMP9. Conversely, the tRF-Gly-CCC-039 inhibitor could attenuate high-glucose-induced endothelial injury to HUVECs. Conclusion: We investigated the tsRNAs expression profile in diabetic foot ulcers and defined the impairment role of tRF-Gly-CCC-039 in endothelial function in HUVECs. This study may provide novel insights into accelerating diabetic skin wound healing.

17.
PeerJ ; 11: e15620, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37520254

RESUMO

Introduction: The use of extended criteria donor (ECD) grafts such as donor with infection of hepatitis B virus (HBV) is a potential solution for organ shortage. In this study, we aimed to evaluate the safety and long-term survival of utilization of hepatitis B surface antigen-positive (HBsAg+) donor livers in HCC patients using propensity score matching (PSM) analysis. Methods: Forty-eight donors with HBsAg-positive and 279 donors with HBsAg-negative were transplanted and enrolled in this study. PSM analysis were used to eliminate selection bias. Perioperative data and survival were collected and analyzed. Results: PSM generated 44 patient pairs. When comparing intra- and post-operative data, no significant difference was found between groups (P > 0.05). Patients with a HBsAg-positive donor had significantly worse progression-free survival (1-year: 65.9% vs. 90.9%; 3-year: 18.1% vs. 70.4%, P = 0.0060) and overall survival (1-year: 84.1% and 95.4%; 3-year: 27.2% vs. 79.5%, P = 0.0039). In multivariate analysis, donor HBsAg-positivity was an independent risk factor for survival and occurrence (P = 0.005 and 0.025, respectively). Conclusion: In conclusion, with adequate antiviral prophylaxis and treatment, utilization of HBsAg positive liver grafts did not increase the incidence of early-stage complications. However, patient with an HBsAg-positive graft had poorer progression-free survival and overall survival.

18.
Nanomaterials (Basel) ; 13(1)2023 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-36616124

RESUMO

Bi2MoO6 was one of the important bismuth-based semiconductors with a narrow bandgap, and has been widely used in selective oxidation catalysts, supercapacitors, and energy-storage devices. A series of Bi2MoO6/ZnO composite photocatalysts with different mass ratios were synthesized by the hydrothermal method. The synthesized samples were characterized by XRD, PL, UV-Vis, SEM, TEM, XPS, and BET analysis techniques. Under visible light conditions, Methylene blue (MB) was used as the target degradation product to evaluate its photocatalytic performance. The results showed that the degradation rate constant of Bi2MoO6/ZnO (0.4-BZO) was about twice that of the traditional photocatalysis of ZnO. The Bi2MoO6/ZnO composite catalyst maintained stable performance after four consecutive runs. The high photocatalytic activity of Bi2MoO6/ZnO was attributed to the efficient electron transport of the heterojunction, which accelerates the separation of electron-hole pairs and reduces the probability of carrier recombination near the Bi2MoO6/ZnO heterojunction. Bi2MoO6/ZnO nanocomposites have potential applications in the field of photodegradation.

19.
Foods ; 12(5)2023 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-36900437

RESUMO

Depression is a chronic mental illness with devastating effects on a person's physical and mental health. Studies have reported that food fermentation with probiotics can enrich the nutritional values of food and produce functional microorganisms that can alleviate depression and anxiety. Wheat germ is an inexpensive raw material that is rich in bioactive ingredients. For example, gamma-aminobutyric acid (GABA) is reported to have antidepressant effects. Several studies concluded that Lactobacillus plantarum is a GABA-producing bacteria and can alleviate depression. Herein, fermented wheat germs (FWGs) were used to treat stress-induced depression. FWG was prepared by fermenting wheat germs with Lactobacillus plantarum. The chronic unpredictable mild stress (CUMS) model was established in rats, and these rats were treated with FWG for four weeks to evaluate the effects of FWG in relieving depression. In addition, the study also analyzed the potential anti-depressive mechanism of FWG based on behavioral changes, physiological and biochemical index changes, and intestinal flora changes in depressed rats. The results demonstrated that FWG improved depression-like behaviors and increased neurotransmitter levels in the hippocampus of CUMS model rats. In addition, FWG effectively altered the gut microbiota structure and remodeled the gut microbiota in CUMS rats, restored neurotransmitter levels in depressed rats through the brain-gut axis, and restored amino acid metabolic functions. In conclusion, we suggest that FWG has antidepressant effects, and its potential mechanism may act by restoring the disordered brain-gut axis.

20.
Appl Biochem Biotechnol ; 195(7): 4399-4413, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36696038

RESUMO

Fructose, which is produced by the isomerization of glucose isomerase, is a crucial precursor for the biosynthesis of rare sugars. In this study, thermophilic glucose isomerases (GI) from Caldicellulosiruptor acetigenus (CAGI), Thermoanaerobacter thermocopriae (TTGI), and Thermotoga petrophila (TPGI) were screened from GenBank database by a virtual probe and were successfully expressed in Escherichia coli BL21(DE3). The results of characterization demonstrated that the optimal pH for CAGI and TTGI were 8.0 and were maintained at 80% in a slightly acidic environment. The relative residual activities of CAGI and TTGI were found to be 40.6% and 52.6%, respectively, following an incubation period of 24 h at 90 ℃. Furthermore, CAGI and TTGI exhibited superior catalytic performance that their reaction equilibrium both reached only after an hour at 85 ℃ with 200 g/L glucose, and the highest conversion rates were 54.2% and 54.1%, respectively. This study identifies competitive enzyme candidates for fructose production in the industry with appreciable cost reduction.


Assuntos
Aldose-Cetose Isomerases , Glucose , Glucose/química , Frutose/química , Aldose-Cetose Isomerases/genética , Aldose-Cetose Isomerases/química , Clostridiales , Clostridium , Tecnologia , Concentração de Íons de Hidrogênio , Proteínas Recombinantes
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