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1.
Nat Immunol ; 24(1): 148-161, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36577929

RESUMO

Regulatory T (Treg) cells have an immunosuppressive function and highly express the immune checkpoint receptor PD-1 in the tumor microenvironment; however, the function of PD-1 in tumor-infiltrating (TI) Treg cells remains controversial. Here, we showed that conditional deletion of PD-1 in Treg cells delayed tumor progression. In Pdcd1fl/flFoxp3eGFP-Cre-ERT2(+/-) mice, in which both PD-1-expressing and PD-1-deficient Treg cells coexisted in the same tissue environment, conditional deletion of PD-1 in Treg cells resulted in impairment of the proliferative and suppressive capacity of TI Treg cells. PD-1 antibody therapy reduced the TI Treg cell numbers, but did not directly restore the cytokine production of TI CD8+ T cells in TC-1 lung cancer. Single-cell analysis indicated that PD-1 signaling promoted lipid metabolism, proliferation and suppressive pathways in TI Treg cells. These results suggest that PD-1 ablation or inhibition can enhance antitumor immunity by weakening Treg cell lineage stability and metabolic fitness in the tumor microenvironment.


Assuntos
Neoplasias , Linfócitos T Reguladores , Animais , Camundongos , Linfócitos T CD8-Positivos , Expressão Gênica , Linfócitos do Interstício Tumoral , Neoplasias/metabolismo , Receptor de Morte Celular Programada 1/metabolismo , Microambiente Tumoral
2.
Nat Immunol ; 24(8): 1308-1317, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37365384

RESUMO

Virtual memory T (TVM) cells are a T cell subtype with a memory phenotype but no prior exposure to foreign antigen. Although TVM cells have antiviral and antibacterial functions, whether these cells can be pathogenic effectors of inflammatory disease is unclear. Here we identified a TVM cell-originated CD44super-high(s-hi)CD49dlo CD8+ T cell subset with features of tissue residency. These cells are transcriptionally, phenotypically and functionally distinct from conventional CD8+ TVM cells and can cause alopecia areata. Mechanistically, CD44s-hiCD49dlo CD8+ T cells could be induced from conventional TVM cells by interleukin (IL)-12, IL-15 and IL-18 stimulation. Pathogenic activity of CD44s-hiCD49dlo CD8+ T cells was mediated by NKG2D-dependent innate-like cytotoxicity, which was further augmented by IL-15 stimulation and triggered disease onset. Collectively, these data suggest an immunological mechanism through which TVM cells can cause chronic inflammatory disease by innate-like cytotoxicity.


Assuntos
Alopecia em Áreas , Linfócitos T CD8-Positivos , Humanos , Interleucina-15 , Memória Imunológica , Subpopulações de Linfócitos T
4.
Cell ; 163(4): 960-74, 2015 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-26544941

RESUMO

Alterations in estrogen-mediated cellular signaling play an essential role in the pathogenesis of endometriosis. In addition to higher estrogen receptor (ER) ß levels, enhanced ERß activity was detected in endometriotic tissues, and the inhibition of enhanced ERß activity by an ERß-selective antagonist suppressed mouse ectopic lesion growth. Notably, gain of ERß function stimulated the progression of endometriosis. As a mechanism to evade endogenous immune surveillance for cell survival, ERß interacts with cellular apoptotic machinery in the cytoplasm to inhibit TNF-α-induced apoptosis. ERß also interacts with components of the cytoplasmic inflammasome to increase interleukin-1ß and thus enhance its cellular adhesion and proliferation properties. Furthermore, this gain of ERß function enhances epithelial-mesenchymal transition signaling, thereby increasing the invasion activity of endometriotic tissues for establishment of ectopic lesions. Collectively, we reveal how endometrial tissue generated by retrograde menstruation can escape immune surveillance and develop into sustained ectopic lesions via gain of ERß function.


Assuntos
Endometriose/patologia , Receptor beta de Estrogênio/metabolismo , Inflamassomos/metabolismo , Menstruação/metabolismo , Animais , Apoptose , Adesão Celular , Proliferação de Células , Endometriose/metabolismo , Receptor alfa de Estrogênio/metabolismo , Feminino , Humanos , Vigilância Imunológica , Interleucina-1beta/metabolismo , Camundongos , Fator de Necrose Tumoral alfa/metabolismo
5.
Nature ; 610(7930): 67-73, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36131017

RESUMO

The high volatility of the price of cobalt and the geopolitical limitations of cobalt mining have made the elimination of Co a pressing need for the automotive industry1. Owing to their high energy density and low-cost advantages, high-Ni and low-Co or Co-free (zero-Co) layered cathodes have become the most promising cathodes for next-generation lithium-ion batteries2,3. However, current high-Ni cathode materials, without exception, suffer severely from their intrinsic thermal and chemo-mechanical instabilities and insufficient cycle life. Here, by using a new compositionally complex (high-entropy) doping strategy, we successfully fabricate a high-Ni, zero-Co layered cathode that has extremely high thermal and cycling stability. Combining X-ray diffraction, transmission electron microscopy and nanotomography, we find that the cathode exhibits nearly zero volumetric change over a wide electrochemical window, resulting in greatly reduced lattice defects and local strain-induced cracks. In-situ heating experiments reveal that the thermal stability of the new cathode is significantly improved, reaching the level of the ultra-stable NMC-532. Owing to the considerably increased thermal stability and the zero volumetric change, it exhibits greatly improved capacity retention. This work, by resolving the long-standing safety and stability concerns for high-Ni, zero-Co cathode materials, offers a commercially viable cathode for safe, long-life lithium-ion batteries and a universal strategy for suppressing strain and phase transformation in intercalation electrodes.

6.
Proc Natl Acad Sci U S A ; 120(23): e2221707120, 2023 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-37253006

RESUMO

Steroid receptor coactivator 3 (SRC-3) is most strongly expressed in regulatory T cells (Tregs) and B cells, suggesting that it plays an important role in the regulation of Treg function. Using an aggressive E0771 mouse breast cell line syngeneic immune-intact murine model, we observed that breast tumors were "permanently eradicated" in a genetically engineered tamoxifen-inducible Treg-cell-specific SRC-3 knockout (KO) female mouse that does not possess a systemic autoimmune pathological phenotype. A similar eradication of tumor was noted in a syngeneic model of prostate cancer. A subsequent injection of additional E0771 cancer cells into these mice showed continued resistance to tumor development without the need for tamoxifen induction to produce additional SRC-3 KO Tregs. SRC-3 KO Tregs were highly proliferative and preferentially infiltrated into breast tumors by activating the chemokine (C-C motif) ligand (Ccl) 19/Ccl21/chemokine (C-C motif) receptor (Ccr)7 signaling axis, generating antitumor immunity by enhancing the interferon-γ/C-X-C motif chemokine ligand (Cxcl) 9 signaling axis to facilitate the entrance and function of effector T cells and natural killer cells. SRC-3 KO Tregs also show a dominant effect by blocking the immune suppressive function of WT Tregs. Importantly, a single adoptive transfer of SRC-3 KO Tregs into wild-type E0771 tumor-bearing mice can completely abolish preestablished breast tumors by generating potent antitumor immunity with a durable effect that prevents tumor reoccurrence. Therefore, treatment with SRC-3-deleted Tregs represents an approach to completely block tumor growth and recurrence without the autoimmune side effects that typically accompany immune checkpoint modulators.


Assuntos
Neoplasias da Mama , Neoplasias Mamárias Animais , Coativador 3 de Receptor Nuclear , Animais , Feminino , Masculino , Camundongos , Ligantes , Camundongos Knockout , Coativador 3 de Receptor Nuclear/genética , Linfócitos T Reguladores , Tamoxifeno/farmacologia
7.
Proc Natl Acad Sci U S A ; 119(15): e2119429119, 2022 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-35377791

RESUMO

Charge density waves (CDWs) have been observed in nearly all families of copper-oxide superconductors. But the behavior of these phases across different families has been perplexing. In La-based cuprates, the CDW wavevector is an increasing function of doping, exhibiting the so-called Yamada behavior, while in Y- and Bi-based materials the behavior is the opposite. Here, we report a combined resonant soft X-ray scattering (RSXS) and neutron scattering study of charge and spin density waves in isotopically enriched La1.8−xEu0.2SrxCuO4 over a range of doping 0.07≤x≤0.20. We find that the CDW amplitude is temperature independent and develops well above experimentally accessible temperatures. Further, the CDW wavevector shows a nonmonotonic temperature dependence, exhibiting Yamada behavior at low temperature with a sudden change occurring near the spin ordering temperature. We describe these observations using a Landau­Ginzburg theory for an incommensurate CDW in a metallic system with a finite charge compressibility and spin-CDW coupling. Extrapolating to high temperature, where the CDW amplitude is small and spin order is absent, our analysis predicts a decreasing wavevector with doping, similar to Y and Bi cuprates. Our study suggests that CDW order in all families of cuprates forms by a common mechanism.

8.
Ophthalmology ; 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-39089371

RESUMO

PURPOSE: To determine the association between pentosan polysulfate (PPS) use and the subsequent development of maculopathy in Asian population. DESIGN: A nationwide population-based retrospective cohort study using the Health Insurance Review and Assessment Service database. PARTICIPANTS: 103,553 individuals in the PPS user group and 205,792 individuals in the PPS non-user group, all newly diagnosed with cystitis between 2009 and 2020. METHODS: The association between PPS use and maculopathy was evaluated using a time dependent Cox proportional hazard model. Additionally, two sensitivity analyses were conducted by defining PPS users as individuals with an observation period over 6 months from the initial prescription or those with cumulative dose exceeding 9 g, employing the same analysis. MAIN OUTCOME MEASURES: The outcome measures included the hazard ratios (HR) representing the association between PPS use and maculopathy. RESULTS: PPS use was associated with an increased risk of subsequent maculopathy in univariate (HR, 1.7; 95% confidence intervals [CI], 1.66-1.75) and multivariate analysis (HR, 1.34; 95% CI, 1.31-1.38). These results were also confirmed in two sensitivity analyses. The mean cumulative dose of PPS for the cohort was 37.2 ± 76.7 g. CONCLUSIONS: In this nationwide cohort study involving an Asian population, individuals with cystitis using PPS exhibit an increased risk of developing subsequent maculopathy.

9.
Phys Rev Lett ; 132(26): 266201, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38996321

RESUMO

We propose helical topological superconductivity away from the Fermi surface in three-dimensional time-reversal-symmetric odd-parity multiband superconductors. In these systems, pairing between electrons originating from different bands is responsible for the corresponding topological phase transition. Consequently, a pair of helical topological Dirac surface states emerges at finite excitation energies. These helical Dirac surface states are tunable in energy by chemical potential and strength of band splitting. They are protected by time-reversal symmetry combined with crystalline twofold rotation symmetry. We suggest concrete materials in which this phenomenon could be observed.

10.
BMC Geriatr ; 24(1): 369, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38658827

RESUMO

BACKGROUND: Regular exercise is emphasized for the improvement of functional capacity and independence of older adults. This study aimed to compare the effects of a dual-task resistance exercise program and resistance exercise on cognition, mood, depression, physical function, and activities of daily living (ADL) in older adults with cognitive impairment. METHODS: A total of 44 older adults participated in the study. Participants were randomly allocated to an experimental group (n = 22) performing a dual-task resistance exercise program for cognitive function improvement and a control group (n = 22) performing a resistance exercise program. Both groups performed the exercise for 40 min per session, three times a week, for 6 weeks (18 sessions). Cognition, mood, depression, functional fitness, and ADL were quantified before and after the intervention using the Mini-Mental State Examination (MMSE), profile of mood states (POMS), geriatric depression scale (GDS), senior fitness test (SFT), and Korean version of ADL, respectively. RESULTS: There was a significant time and group interaction on the MMSE (p = 0.044). There were no significant time and group interactions in the POMS, GDS, SFT, or ADL. Cognitive function (p < 0.001), mood (p < 0.001), depression (p < 0.001), functional fitness (p < 0.001), and ADL (p < 0.001) significantly improved after dual-task resistance exercise, and cognitive function (p < 0.001), mood (p < 0.001), depression (p < 0.001), functional fitness (p < 0.001), and ADL (p < 0.001) significantly improved after resistance exercise. CONCLUSIONS: Dual-task resistance exercise is more effective than resistance exercise in improving cognitive function in older adults with cognitive impairment. Both dual-task resistance exercise and resistance exercise improves mood, depression, functional fitness, and ADL after the intervention. We propose using dual-task resistance exercises for cognitive and physical health management in the older adults with cognitive impairment. TRIAL REGISTRATION: This study was registered with the Clinical Research Information Service (WHO International Clinical Trials Registry Platform) (Registration ID, KCT0005389; Registration date, 09/09/2020).


Assuntos
Atividades Cotidianas , Afeto , Cognição , Disfunção Cognitiva , Depressão , Aptidão Física , Treinamento Resistido , Humanos , Idoso , Masculino , Atividades Cotidianas/psicologia , Feminino , Disfunção Cognitiva/terapia , Disfunção Cognitiva/psicologia , Treinamento Resistido/métodos , Depressão/terapia , Depressão/psicologia , Cognição/fisiologia , Aptidão Física/fisiologia , Aptidão Física/psicologia , Afeto/fisiologia , Método Simples-Cego , Idoso de 80 Anos ou mais
11.
J Korean Med Sci ; 39(27): e203, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39015001

RESUMO

BACKGROUND: The prevalence of diabetes is increasing globally, highlighting the importance of preventive healthcare. This study aimed to identify the diabetic retinopathy (DR) screening rates and risk factors linked to DR screening nonadherence in the Korean population through a nationally representative sample survey. METHODS: Among the Korea National Health and Nutrition Examination Survey database from 2016 to 2021, participants aged ≥ 40 years with diabetes were included. The weighted estimate for nonadherence to DR screening within a year was calculated. Risk factor analyses were conducted using univariate and multivariate logistic regression. RESULTS: Among the 3,717 participants, 1,109 (29.5%) underwent DR screening within the past year, and this national estimate exhibited no statistically significant difference from 2016 to 2021 (P = 0.809). Nonadherence to annual DR screening was associated with residing in rural areas, age ≥ 80 years, low educational level, self-reported good health, absence of ocular disease, current smoking, lack of exercise and dietary diabetes treatment, and no activity limitation (all P < 0.05). CONCLUSION: The recent DR screening rate in Korea was relatively low. Factors associated with apathy and complacency towards personal health were associated with the nonadherence to DR screening. Educational interventions have the potential to enhance the annual screening rate for diabetic patients.


Assuntos
Retinopatia Diabética , Programas de Rastreamento , Inquéritos Nutricionais , Humanos , Retinopatia Diabética/diagnóstico , Retinopatia Diabética/epidemiologia , República da Coreia/epidemiologia , Feminino , Masculino , Pessoa de Meia-Idade , Idoso , Adulto , Fatores de Risco , Idoso de 80 Anos ou mais , Modelos Logísticos , Prevalência , Razão de Chances
12.
Arthroscopy ; 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38331368

RESUMO

PURPOSE: To assess serial changes of preoperative bone marrow lesion (BML) following medial open-wedge high tibial osteotomy (MOWHTO) up to 2 years and evaluate whether postoperative change of BML affected patient-reported outcome measures (PROMs) at 2 years' follow-up. Factors related to the postoperative changes in BML also were evaluated. METHODS: The current study retrospectively assessed prospectively collected data of consecutive patients between December 2016 and March 2018 who underwent MOWHTO for symptomatic knee osteoarthritis with varus malalignment (≥5°) and a minimum 2-year follow-up. Serial magnetic resonance imaging scans at preoperative and postoperative 3, 6, 18, and 24 months were performed, and the extent of BML was evaluated consecutively using 2 validated methods. Clinically, preoperative and postoperative PROMs and their achievement of minimal clinically important difference values were evaluated. The associations of the extent of BMLs with PROMs at each follow-up period over time were analyzed using a linear mixed model. Furthermore, factors related to the postoperative changes of BML were assessed. RESULTS: Of 26 patients, 21 (80.8%) had preoperative BML at medial femoral and tibial condyles. The postoperative decrease in BML was noted in 17 (81.0%) and 18 (85.7%) at medial femoral and tibial condyles. The BML decreased at postoperative 3 months and, thereafter, the extent of BML gradually reduced until postoperative 24 months. The proportion of patients achieved minimal clinically important difference was 84.6% for total Western Ontario and McMaster Universities Osteoarthritis Index scores and 80.8%, 76.9%, and 84.6% for KOOS symptom, pain, and activity of daily living subscales. Postoperative decrease in BML was significantly associated with better PROMs over postoperative 24 months. Furthermore, normo-correction (2°-5° valgus) was a significant factor for decreased BML following MOWHTO. CONCLUSIONS: Preoperative BML gradually decreased with time following MOWHTO, and the postoperative decrease in BML related with better PROMs over postoperative 24 months. Moreover, postoperative valgus alignment was a significant factor relating the postoperative decrease of BML. LEVEL OF EVIDENCE: Level IV, retrospective case series.

13.
Nano Lett ; 23(5): 1743-1751, 2023 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-36811529

RESUMO

P2-Na0.67Ni0.33Mn0.67O2 represents a promising cathode for Na-ion batteries, but it suffers from severe structural degradation upon storing in a humid atmosphere and cycling at a high cutoff voltage. Here we propose an in situ construction to achieve simultaneous material synthesis and Mg/Sn cosubstitution of Na0.67Ni0.33Mn0.67O2 via one-pot solid-state sintering. The materials exhibit superior structural reversibility and moisture insensitivity. In-operando XRD reveals an essential correlation between cycling stability and phase reversibility, whereas Mg substitution suppressed the P2-O2 phase transition by forming a new Z phase, and Mg/Sn cosubstitution enhanced the P2-Z transition reversibility benefiting from strong Sn-O bonds. DFT calculations disclosed high chemical tolerance to moisture, as the adsorption energy to H2O was lower than that of the pure Na0.67Ni0.33Mn0.67O2. A representative Na0.67Ni0.23Mg0.1Mn0.65Sn0.02O2 cathode exhibits high reversible capacities of 123 mAh g-1 (10 mA g-1), 110 mAh g-1 (200 mA g-1), and 100 mAh g-1 (500 mA g-1) and a high capacity retention of 80% (500 mA g-1, 500 cycles).

14.
Medicina (Kaunas) ; 60(5)2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38793022

RESUMO

Background and Objectives: Endoscopic epidural neuroplasty (EEN) facilitates adhesiolysis through direct epiduroscopic visualization, offering more precise neural decompression than that exhibited by percutaneous epidural neuroplasty (PEN). We aimed to compare the effects of EEN and PEN for 6 months after treatment with lower back and radicular pain in patients. Methods: This retrospective study compared the visual analog scale (VAS) and Oswestry disability index (ODI) scores in patients with low back and radicular pain who underwent EEN or PEN with a steering catheter. The medical records of 107 patients were analyzed, with 73 and 34 undergoing EEN and PEN, respectively. Results: The VAS and ODI scores decreased at all time points after EEN and PEN. VAS and ODI scores decreased more in the EEN group than those in the PEN group at 1 day and 1- and 6-months post-procedure, indicating superior pain relief for both lower back and radicular pain through EEN. Conclusions: EEN is a superior treatment of pain control than PEN in lower back and radicular pain patients.


Assuntos
Dor Lombar , Humanos , Dor Lombar/cirurgia , Dor Lombar/terapia , Feminino , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento , Seguimentos , Idoso , Adulto , Endoscopia/métodos , Medição da Dor/métodos , Espaço Epidural , Descompressão Cirúrgica/métodos
15.
J Biol Chem ; 298(12): 102697, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36379252

RESUMO

Organisms must either synthesize or assimilate essential organic compounds to survive. The homocysteine synthase Met15 has been considered essential for inorganic sulfur assimilation in yeast since its discovery in the 1970s. As a result, MET15 has served as a genetic marker for hundreds of experiments that play a foundational role in eukaryote genetics and systems biology. Nevertheless, we demonstrate here through structural and evolutionary modeling, in vitro kinetic assays, and genetic complementation, that an alternative homocysteine synthase encoded by the previously uncharacterized gene YLL058W enables cells lacking Met15 to assimilate enough inorganic sulfur for survival and proliferation. These cells however fail to grow in patches or liquid cultures unless provided with exogenous methionine or other organosulfurs. We show that this growth failure, which has historically justified the status of MET15 as a classic auxotrophic marker, is largely explained by toxic accumulation of the gas hydrogen sulfide because of a metabolic bottleneck. When patched or cultured with a hydrogen sulfide chelator, and when propagated as colony grids, cells without Met15 assimilate inorganic sulfur and grow, and cells with Met15 achieve even higher yields. Thus, Met15 is not essential for inorganic sulfur assimilation in yeast. Instead, MET15 is the first example of a yeast gene whose loss conditionally prevents growth in a manner that depends on local gas exchange. Our results have broad implications for investigations of sulfur metabolism, including studies of stress response, methionine restriction, and aging. More generally, our findings illustrate how unappreciated experimental variables can obfuscate biological discovery.


Assuntos
Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae , Enxofre , Humanos , Sulfeto de Hidrogênio/metabolismo , Metionina/metabolismo , Mutação , Saccharomyces cerevisiae/metabolismo , Enxofre/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo
16.
Kidney Int ; 103(2): 343-356, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36332729

RESUMO

Current treatment strategies for autoimmune diseases may not sufficiently control aberrant metabolism in B-cells. To address this concern, we investigated a biguanide derivative, IM156, as a potential regulator for B-cell metabolism in vitro and in vivo on overactive B-cells stimulated by the pro-inflammatory receptor TLR-9 agonist CpG oligodeoxynucleotide, a mimic of viral/bacterial DNA. Using RNA sequencing, we analyzed the B-cell transcriptome expression, identifying the major molecular pathways affected by IM156 in vivo. We also evaluated the anti-inflammatory effects of IM156 in lupus-prone NZB/W F1 mice. CD19+B-cells exhibited higher mitochondrial mass and mitochondrial membrane potential compared to T-cells and were more susceptible to IM156-mediated oxidative phosphorylation inhibition. In vivo, IM156 inhibited mitochondrial oxidative phosphorylation, cell cycle progression, plasmablast differentiation, and activation marker levels in CpG oligodeoxynucleotide-stimulated mouse spleen B-cells. Interestingly, IM156 treatment significantly increased overall survival, reduced glomerulonephritis and inhibited B-cell activation in the NZB/W F1 mice. Thus, our data indicated that IM156 suppressed the mitochondrial membrane potentials of activated B-cells in mice, contributing to the mitigation of lupus activity. Hence, IM156 may represent a therapeutic alternative for autoimmune disease mediated by B-cell hyperactivity.


Assuntos
Doenças Autoimunes , Lúpus Eritematoso Sistêmico , Camundongos , Animais , Potencial da Membrana Mitocondrial , Fosforilação Oxidativa , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Linfócitos B , Camundongos Endogâmicos NZB , Oligodesoxirribonucleotídeos/farmacologia
17.
Genome Res ; 30(5): 768-775, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32327447

RESUMO

Genome editing has been revolutionized by the CRISPR-Cas9 system. CRISPR-Cas9 is composed of single-molecular guide RNA (sgRNA) and a proteinaceous Cas9 nuclease, which recognizes a specific target sequence and a protospacer adjacent motif (PAM) sequence and, subsequently, cleaves the targeted DNA sequence. This CRISPR-Cas9 system has been used as an efficient negative-selection tool to cleave unedited or unchanged target DNAs during site-specific mutagenesis and, consequently, obtain microbial cells with desired mutations. This study aimed to investigate the genome editing efficiency of the CRISPR-Cas9 system for in vivo oligonucleotide-directed mutagenesis in bacteria. This system successfully introduced two- to four-base mutations in galK in Escherichia coli with high editing efficiencies (81%-86%). However, single-point mutations (T504A or C578A) were rarely introduced with very low editing efficiencies (<3%), probably owing to mismatch tolerance. To resolve this issue, we designed one- or two-base mismatches in the sgRNA sequence to recognize target sequences in galK in E. coli A single-point nucleotide mutation (T504A or C578A in the galK gene) was successfully introduced in 36%-95% of negatively selected E. coli cells using single-base mismatched sgRNAs. Sixteen targets were randomly selected through genome-wide single-base editing experiments using mismatched sgRNAs. Consequently, out of 48 desired single-base mutations, 25 single bases were successfully edited, using mismatched sgRNAs. Finally, applicable design rules for target-mismatched sgRNAs were provided for single-nucleotide editing in microbial genomes.


Assuntos
Sistemas CRISPR-Cas , Edição de Genes/métodos , Pareamento Incorreto de Bases , Proteína 9 Associada à CRISPR/genética , Escherichia coli/genética , Genoma Bacteriano , Mutagênese , Mutação , Plasmídeos/genética , RNA/química
18.
Am J Gastroenterol ; 118(4): 654-663, 2023 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-36594820

RESUMO

INTRODUCTION: For the treatment of spontaneous bacterial peritonitis (SBP), cefotaxime, ceftriaxone, and ciprofloxacin were used as first-line agents. However, considering the increasing rate of antibiotic resistance, it is unclear which of these drugs can be initially recommended. This study aimed to compare the current efficacy of the 3 antibiotics, namely cefotaxime, ceftriaxone, and ciprofloxacin, for the treatment of SBP in patients with cirrhosis with ascites, when guided by therapeutic responses. METHODS: This study was a multicenter, prospective, randomized controlled trial. The inclusion criteria were 16- to 75-year-old patients with liver cirrhosis with ascites, having polymorphonuclear cell count of >250/mm 3 . We performed a follow-up paracentesis at 48 hours to decide continuing or changing the assigned antibiotics and then assessed the resolution rates at 120 and 168 hours of treatment. RESULTS: A total of 261 patients with cirrhosis who developed SBP were enrolled. Most of the patients were diagnosed as those with SBP within 48 hours of admission. The resolution rates at 120 hours, which is the primary endpoint, were 67.8%, 77.0%, and 73.6% in the cefotaxime, ceftriaxone, and ciprofloxacin groups, respectively ( P = 0.388), by intension-to-treat analysis. The 1-month mortality was similar among the groups ( P = 0.770). The model for end-stage liver disease score and the SBP resolution were significant factors for survival. CONCLUSION: The efficacy of empirical antibiotics, such as cefotaxime, ceftriaxone, and ciprofloxacin, against SBP was not significantly different. In addition, these antibiotics administered based on response-guided therapy were still efficacious as initial treatment for SBP, especially in those with community-acquired infections.


Assuntos
Infecções Bacterianas , Doença Hepática Terminal , Peritonite , Humanos , Adolescente , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Idoso , Cefotaxima/uso terapêutico , Ceftriaxona/uso terapêutico , Ciprofloxacina/uso terapêutico , Ascite/tratamento farmacológico , Estudos Prospectivos , Doença Hepática Terminal/tratamento farmacológico , Índice de Gravidade de Doença , Antibacterianos/uso terapêutico , Peritonite/tratamento farmacológico , Peritonite/etiologia , Peritonite/diagnóstico , Cirrose Hepática/terapia , Infecções Bacterianas/complicações , Infecções Bacterianas/tratamento farmacológico , Infecções Bacterianas/microbiologia
19.
J Transl Med ; 21(1): 263, 2023 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-37069607

RESUMO

BACKGROUND: Non-alcoholic fatty liver disease (NAFLD) is a serious public health issue globally, currently, the treatment of NAFLD lies still in the labyrinth. In the inchoate stage, the combinatorial application of food regimen and favorable gut microbiota (GM) are considered as an alternative therapeutic. Accordingly, we integrated secondary metabolites (SMs) from GM and Avena sativa (AS) known as potent dietary grain to identify the combinatorial efficacy through network pharmacology. METHODS: We browsed the SMs of AS via Natural Product Activity & Species Source (NPASS) database and SMs of GM were retrieved by gutMGene database. Then, specific intersecting targets were identified from targets related to SMs of AS and GM. The final targets were selected on NAFLD-related targets, which was considered as crucial targets. The protein-protein interaction (PPI) networks and bubble chart analysis to identify a hub target and a key signaling pathway were conducted, respectively. In parallel, we analyzed the relationship of GM or AS─a key signaling pathway─targets─SMs (GASTM) by merging the five components via RPackage. We identified key SMs on a key signaling pathway via molecular docking assay (MDA). Finally, the identified key SMs were verified the physicochemical properties and toxicity in silico platform. RESULTS: The final 16 targets were regarded as critical proteins against NAFLD, and Vascular Endothelial Growth Factor A (VEGFA) was a key target in PPI network analysis. The PI3K-Akt signaling pathway was the uppermost mechanism associated with VEGFA as an antagonistic mode. GASTM networks represented 122 nodes (60 GM, AS, PI3K-Akt signaling pathway, 4 targets, and 56 SMs) and 154 edges. The VEGFA-myricetin, or quercetin, GSK3B-myricetin, IL2-diosgenin complexes formed the most stable conformation, the three ligands were derived from GM. Conversely, NR4A1-vestitol formed stable conformation with the highest affinity, and the vestitol was obtained from AS. The given four SMs were no hurdles to develop into drugs devoid of its toxicity. CONCLUSION: In conclusion, we show that combinatorial application of AS and GM might be exerted to the potent synergistic effects against NAFLD, dampening PI3K-Akt signaling pathway. This work provides the importance of dietary strategy and beneficial GM on NAFLD, a data mining basis for further explicating the SMs and pharmacological mechanisms of combinatorial application (AS and GM) against NAFLD.


Assuntos
Medicamentos de Ervas Chinesas , Microbioma Gastrointestinal , Hepatopatia Gordurosa não Alcoólica , Avena , Simulação de Acoplamento Molecular , Farmacologia em Rede , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Fosfatidilinositol 3-Quinases , Proteínas Proto-Oncogênicas c-akt , Fator A de Crescimento do Endotélio Vascular
20.
Nat Mater ; 21(10): 1144-1149, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35927432

RESUMO

Van der Waals heterostructures with two-dimensional magnets offer a magnetic junction with an atomically sharp and clean interface. This attribute ensures that the magnetic layers maintain their intrinsic spin-polarized electronic states and spin-flipping scattering processes at a minimum level, a trait that can expand spintronic device functionalities. Here, using a van der Waals assembly of ferromagnetic Fe3GeTe2 with non-magnetic hexagonal boron nitride and WSe2 layers, we demonstrate electrically tunable, highly transparent spin injection and detection across the van der Waals interfaces. By varying an electrical bias, the net spin polarization of the injected carriers can be modulated and reversed in polarity, which leads to sign changes of the tunnelling magnetoresistance. We attribute the spin polarization reversals to sizable contributions from high-energy localized spin states in the metallic ferromagnet, so far inaccessible in conventional magnetic junctions. Such tunability of the spin-valve operations opens a promising route for the electronic control of next-generation low-dimensional spintronic device applications.

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