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1.
Immun Inflamm Dis ; 12(5): e1277, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38775687

RESUMO

BACKGROUND: Kawasaki disease (KD) is an autoimmune disease with cardiovascular disease as its main complication, mainly affecting children under 5 years old. KD treatment has made tremendous progress in recent years, but intravenous immunoglobulin (IVIG) resistance remains a major dilemma. Bibliometric analysis had not been used previously to summarize and analyze publications related to IVIG resistance in KD. This study aimed to provide an overview of the knowledge framework and research hotspots in this field through bibliometrics, and provide references for future basic and clinical research. METHODS: Through bibliometric analysis of relevant literature published on the Web of Science Core Collection (WoSCC) database between 1997 and 2023, we investigated the cooccurrence and collaboration relationships among countries, institutions, journals, and authors and summarized key research topics and hotspots. RESULTS: Following screening, a total of 364 publications were downloaded, comprising 328 articles and 36 reviews. The number of articles on IVIG resistance increased year on year and the top three most productive countries were China, Japan, and the United States. Frontiers in Pediatrics had the most published articles, and the Journal of Pediatrics had the most citations. IVIG resistance had been studied by 1889 authors, of whom Kuo Ho Chang had published the most papers. CONCLUSION: Research in the field was focused on risk factors, therapy (atorvastatin, tumor necrosis factor-alpha inhibitors), pathogenesis (gene expression), and similar diseases (multisystem inflammatory syndrome in children, MIS-C). "Treatment," "risk factor," and "prediction" were important keywords, providing a valuable reference for scholars studying this field. We suggest that, in the future, more active international collaborations are carried out to study the pathogenesis of IVIG insensitivity, using high-throughput sequencing technology. We also recommend that machine learning techniques are applied to explore the predictive variables of IVIG resistance.


Assuntos
Bibliometria , Resistência a Medicamentos , Imunoglobulinas Intravenosas , Síndrome de Linfonodos Mucocutâneos , Síndrome de Linfonodos Mucocutâneos/tratamento farmacológico , Síndrome de Linfonodos Mucocutâneos/epidemiologia , Humanos , Imunoglobulinas Intravenosas/uso terapêutico
2.
PhytoKeys ; 241: 131-141, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38690579

RESUMO

This study provides detailed description of a newly-discovered Callicarpayongshunensis Wen B. Xu, Xiao D. Li & Yan Ling Liu (Lamiaceae) species from Hunan, China. The species shares similarities in the inflorescence, glandular colour and leaf shape features with C.luteopunctata H. T. Chang and C.giraldii Hesse ex Rehd., while its white fruits are similar to those of C.longifolia Lamk. However, its procumbent, evergreen shrub and white fruits are distinctly different from those of C.luteopunctata and C.giraldii, while its procumbent, scarless nodes and stellate pubescence free fruits distinguishes it from C.longifolia. Images, distribution, morphological features, molecular phylogenetic classification and conservation assessment of this new Callicarpa species are explored.

3.
Virol Sin ; 2024 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-38768713

RESUMO

As of December 2022, 2,603 cases laboratory-identified Middle East respiratory syndrome coronavirus (MERS-CoV) infections and 935 associated deaths, with a mortality rate of 36%, had been reported to the World Health Organization (WHO). However, there are still no vaccines for MERS-CoV, which makes the prevention and control of MERS-CoV difficult. In this study, we constructed two vaccine candidates of DNA and replicating Vaccinia Tian Tan (VTT) vector that carried the MERS-CoV Spike (S) protein. Compared with homologous immunization with either vaccine, mice immunized with DNA vaccine prime and VTT vaccine boost exhibited much stronger and durable humoral and cellular immune responses. The mice immunized generated robust binding antibodies and broader neutralizing antibodies against the EMC2012, England1 and KNIH strains of MERS-CoV. Prime-Boost immunization also induced strong MERS-S specific T cells responses, with high memory and poly-functional (CD107a-IFN-γ-TNF-α) effector CD8+ T cells. In conclusion, the research demonstrated that DNA-Prime/VTT-Boost strategy could elicit robust and balanced humoral and cellular immune responses against MERS-CoV-S. This study not only provides a promising set of MERS-CoV vaccine candidates but also proposes a heterologous sequential immunization strategy worthy of further development.

4.
Phytochemistry ; 224: 114140, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38750709

RESUMO

Eight previously undescribed cevanine-type steroidal alkaloids, cirrhosinones I-N and cirrhosinols A-B, along with five known analogs, were isolated from the bulbs of Fritillaria cirrhosa D. Don. Their structures were elucidated on the basis of comprehensive analysis of HRESIMS, 1D and 2D NMR spectroscopic data, and single-crystal X-ray diffraction analyses. All compounds revealed weak NO inhibitory activities in the LPS-stimulated NR8383 cells at the concentration of 20 µM, with inhibition ratios ranging from 5.1% to 14.3%.

5.
J Appl Gerontol ; : 7334648241241392, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38652679

RESUMO

This study explored the association between diabetes, cognitive imFpairment (CI), and mortality in a cohort of 2931 individuals aged 60 and above from the 2011 to 2014 NHANES. Mortality data was gathered through 2019, and multivariable Cox proportional hazards models were used to determine the association between diabetes, CI, and mortality adjusting for sociodemographic characteristics, lifestyle factors, and comorbidity conditions. The study spanned up to 9.17 years, observing 579 deaths, with individuals having both diabetes and CI showing the highest all-cause mortality (23.6 events per 100 patient-years). Adjusted analysis revealed a 2.34-fold higher risk of all-cause mortality for this group, surpassing those with diabetes or CI alone. These results held after a series of stratified and sensitivity analyses. In conclusion, CI was linked to higher all-cause mortality in individuals with diabetes, emphasizing the need to address cognitive dysfunction in diabetic patients.

6.
Integr Zool ; 2024 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-38644525

RESUMO

Musk secreted by male forest musk deer (Moschus berezovskii) musk glands is an invaluable component of medicine and perfume. Musk secretion depends on musk gland maturation; however, the mechanism of its development remains elusive. Herein, using single cell multiome ATAC + gene expression coupled with several bioinformatic analyses, a dynamic transcriptional cell atlas of musk gland development was revealed, and key genes and transcription factors affecting its development were determined. Twelve cell types, including two different types of acinar cells (Clusters 0 and 10) were identified. Single-nucleus RNA and single-nucleus ATAC sequencing analyses revealed that seven core target genes associated with musk secretion (Hsd17b2, Acacb, Lss, Vapa, Aldh16a1, Aldh7a1, and Sqle) were regulated by 12 core transcription factors (FOXO1, CUX2, RORA, RUNX1, KLF6, MGA, NFIC, FOXO3, ETV5, NR3C1, HSF4, and MITF) during the development of Cluster 0 acinar cells. Kyoto Encyclopedia of Genes and Genomes enrichment showed significant changes in the pathways associated with musk secretion during acinar cell development. Gene set variation analysis also revealed that certain pathways associated with musk secretion were enriched in 6-year-old acinar cells. A gene co-expression network was constructed during acinar cell development to provide a precise understanding of the connections between transcription factors, genes, and pathways. Finally, intercellular communication analysis showed that intercellular communication is involved in musk gland development. This study provides crucial insights into the changes and key factors underlying musk gland development, which serve as valuable resources for studying musk secretion mechanisms and promoting the protection of this endangered species.

7.
Forensic Toxicol ; 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38642241

RESUMO

PURPOSE: A rapid and reliable method was developed and validated for the simultaneous analysis of 52 antibiotics (cephalosporins, penicillins, carbapenems, lincosamides, quinolones, nitroimidazoles, macrolides, sulfonamides, tetracyclines, glycopeptide) in urine and whole blood by high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). METHOD: Analytes were extracted by dilution or protein precipitation and analyzed on an Agilent 1260 HPLC system coupled to an Agilent 6470 Triple Quadrupole Mass Spectrometer. RESULTS: The method attended method validation criteria. The limits of detection were equal or lower than 2.0 ng/mL, whereas the limits of quantification ranged from 0.1 to 10.0 ng/mL, from 0.1 to 5.0 ng/mL, in urine and whole blood, respectively. For all analytes, the bias and intra- and inter-day precision values were less than 14.7%. The ranges of recovery values of all antibiotics were 76.5-124.5% in whole blood and 76.3-121.8% in urine, values of the effects were lower than 25% in two matrices. No evidence of carryover was observed. The study of sample stability showed that almost all analytes were stable at 24 °C for 24 h, all analytes were stable at -20 °C for 14 days and at -80 °C for 30 days. Freeze-thaw cycles stability showed that antibiotics were stable except for imipenem. Autosampler stability study showed that all analytes were stable for 24 h, except for imipenem and amoxicillin. Applicability was proven by analyzing authentic whole blood (n = 86) and urine (n = 79) samples from patients under antibiotics treatment. Therefore, this method was applied to the analysis 3 forensic allergy cases, which were positive for at least one analyte. CONCLUSIONS: A simple, sensitive and high-throughput method for the simultaneous determination of different classes of antibiotics in urine and whole blood samples was developed and applied. This sensitive method was successfully applied to forensic cases.

8.
BMC Public Health ; 24(1): 1047, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38622567

RESUMO

BACKGROUND: Adverse childhood experiences (ACEs) might be associated with maternal spontaneous fetal loss, while evidence among Chinese population is limited. This study aims to explore the associations of adverse childhood experiences (ACEs) among women and their spouses with the risk of spontaneous abortion and stillbirth. METHOD: Data were from the China Health and Retirement Longitudinal Study (CHARLS) 2014 survey. ACEs were categorized into intra-familial ACEs and extra-familial ACEs. The associations of maternal and paternal ACEs with women's history of spontaneous abortion and stillbirth were investigated by logistic regression. RESULTS: 7,742 women were included with 9.05% and 2.47% experiencing at least one spontaneous abortion or stillbirth, respectively. Women exposed to 2, 3, and ≥ 4 ACEs were at significantly higher odds of spontaneous abortion, with adjusted odds ratios (ORs) of 1.52 (95% [CI, Confidence Interval] 1.10-2.10), 1.50 (95% CI 1.07-2.09) and 1.68 (95% CI 1.21-2.32), respectively. A significant association between ≥ 4 maternal intra-familial ACEs and stillbirth (OR 2.23, 95% CI 1.12-4.42) was also revealed. Furthermore, paternal exposures to 3 and ≥ 4 overall ACEs were significantly associated with their wives' history of spontaneous abortion, with adjusted ORs of 1.81 (95% CI 1.01-3.26) and 1.83 (95% CI 1.03-3.25), respectively. CONCLUSION: Both maternal and paternal ACEs were associated with spontaneous abortion, and potential mediators might need to be considered to further explore impacts of maternal and paternal ACEs on maternal reproductive health.


Assuntos
Aborto Espontâneo , Experiências Adversas da Infância , Gravidez , Masculino , Humanos , Feminino , Aborto Espontâneo/epidemiologia , Natimorto/epidemiologia , Estudos Transversais , Exposição Materna , Estudos Longitudinais
9.
Nutr Metab (Lond) ; 21(1): 22, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38658956

RESUMO

BACKGROUND: Spexin, a 14 amino acid peptide, has been reported to regulate obesity and its associated complications. However, little is known about the underlying molecular mechanism. Therefore, this study aimed to investigate the effects of spexin on obesity and explore the detailed molecular mechanisms in vivo and in vitro. METHODS: Male C57BL/6J mice were fed a high-fat diet (HFD) for 12 weeks to induce obesity, and mice fed a standard fat diet were used as controls. Then, these mice were treated with SPX or Vehicle by intraperitoneal injection for an additional 12 weeks, respectively. The metabolic profile, fat-browning specific markers and mitochondrial contents were detected. In vitro, 3T3-L1 cells were used to investigate the molecular mechanisms. RESULTS: After 12 weeks of treatment, SPX significantly decreased body weight, serum lipid levels, and improved insulin sensitivity in HFD-induced obese mice. Moreover, SPX was found to promote oxygen consumption in HFD mice, and it increased mitochondrial content as well as the expression of brown-specific markers in white adipose tissue (WAT) of HFD mice. These results were consistent with the increase in mitochondrial content and the expression of brown-specific markers in 3T3-L1 mature adipocytes. Of note, the spexin-mediated beneficial pro-browning actions were abolished by the JAK2/STAT3 pathway antagonists in mature 3T3-L1 cells. CONCLUSIONS: These data indicate that spexin ameliorates obesity-induced metabolic disorders by improving WAT browning via activation of the JAK2/STAT3 signaling pathway. Therefore, SPX may serve as a new therapeutic candidate for treating obesity.

10.
Artigo em Inglês | MEDLINE | ID: mdl-38683715

RESUMO

Video activity anticipation aims to predict what will happen in the future, embracing a broad application prospect ranging from robot vision and autonomous driving. Despite the recent progress, the data uncertainty issue, reflected as the content evolution process and dynamic correlation in event labels, has been somehow ignored. This reduces the model generalization ability and deep understanding on video content, leading to serious error accumulation and degraded performance. In this paper, we address the uncertainty learning problem and propose an uncertainty-boosted robust video activity anticipation framework, which generates uncertainty values to indicate the credibility of the anticipation results. The uncertainty value is used to derive a temperature parameter in the softmax function to modulate the predicted target activity distribution. To guarantee the distribution adjustment, we construct a reasonable target activity label representation by incorporating the activity evolution from the temporal class correlation and the semantic relationship. Moreover, we quantify the uncertainty into relative values by comparing the uncertainty among sample pairs and their temporal-lengths. This relative strategy provides a more accessible way in uncertainty modeling than quantifying the absolute uncertainty values on the whole dataset. Experiments on multiple backbones and benchmarks show our framework achieves promising performance and better robustness/interpretability. Source codes are available at https://github.com/qzhb/UbRV2A.

11.
Virus Res ; 345: 199377, 2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38643858

RESUMO

The membrane-proximal external region (MPER) represents a highly conserved region of the Human Immunodeficiency Virus (HIV) envelope glycoprotein (env) targeted by several broadly neutralizing antibodies (bnAbs). In this study, we employed single genome amplification to amplify 34 full-length env sequences from the 2005 plasma sample of CBJC504, a chronic HIV-1 clade B infected individual. We identified three amino acid changes (N671S, D674N, and K677R) in the MPER. A longitudinal analysis revealed that the proportion of env sequences with MPER mutations increased from 26.5 % in 2005 to 56.0 % in 2009, and the sequences with the same mutation clustered together. Nine functional pseudoviruses were generated from the 34 env sequences to examine the effect of these mutations on neutralizing activity. Pseudoviruses carrying N674 or R677 mutations demonstrate increased sensitivity to autologous plasma and monoclonal antibodies 2F5, 4E10, and 10E8. Reverse mutations were performed in env including N674, R677, D659, and S671/N677 mutations, to validate the impact of the mutations on neutralizing sensitivity. Neutralization assays indicated that the N671S mutation increased neutralization sensitivity to 2F5 and 10E8. The amino acid R at position 677 increased viral resistance to 10E8, whereas N enhanced viral resistance to 4E10 and 10E8. It has been proposed that critical amino acids in the extra-MPER and the number of potential N-like glycosylation sites (PNGSs) in the V1 loop may have an impact on neutralizing activity. Understanding the mutations and evolution of MPER in chronically infected patients with HIV-1 is crucial for the design and development of vaccines that trigger bnAbs against MPER.

12.
J Anim Sci ; 1022024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38651250

RESUMO

Immunoglobulin is an essential component of the body's defense against pathogens, aiding in the recognition and clearance of foreign antigens. Research concerning immunoglobulin gene and its diversity of expression across different breeds within the same species is relatively scarce. In this study, we employed RACE (Rapid Amplification of cDNA Ends) technology, prepared DNA libraries, performed high-throughput sequencing, and conducted related bioinformatics analysis to analyze the differences in immunoglobulin gene diversity and expression at different periods in Hy-line brown hens, Lueyang black-bone chickens, and Beijing-You chickens. The study found that the composition of chicken immunoglobulin genes is relatively simple, with both the light chain and heavy chain having a functional V gene. Additionally, the mechanisms of immunoglobulin diversity generation tended to be consistent among different breeds and periods of chickens, primarily relying on abundant junctional diversity, somatic hypermutation (SHM), and gene conversion (GCV) to compensate for the limitations of low-level V(D)J recombination. As the age increased, the junctional diversity of IgH and IgL tended to diversify and showed similar expression patterns among different breeds. In the three chicken breeds, the predominant types of mutations observed in IGHV and IGLV SHM were A to G and G to A transitions. Specifically, IGLV exhibited a preference for A to G mutations, whereas IGHV displayed a bias toward G to A mutations. The regions at the junctions between framework regions (FR) and complementarity-determining regions (CDR) and within the CDR regions themselves are typically prone to mutations. The locations of GCV events in IGLV and IGHV do not show significant differences, and replacement segments are concentrated in the central regions of FR1, CDR, and FR2. Importantly, gene conversion events are not random occurrences. Additionally, our investigation revealed that CDRH3 in chickens of diverse breeds and periods the potential for diversification through the incorporation of cysteine. This study demonstrates that the diversity of immunoglobulin expression tends to converge among Hy-line brown hens, Lueyang black-bone chickens, and Beijing-You chickens, indicating that the immunoglobulin gene expression mechanisms in different breeds of chickens do not exhibit significant differences due to selective breeding.


Immunoglobulins play a key role in the organism's defense against pathogens, and their diverse expression allows the body to generate a wide array of antibodies. This diversity serves as a critical safeguard for the immune system against various pathogens. Natural geographical variances and artificial breeding and selection can potentially lead to different immune responses in distinct populations of the same species when confronted with the same pathogen. In this study, we investigated the diversity of immunoglobulin gene expression in the natural state of different chicken breeds (Hy-line brown hens, Lueyang black-bone chickens, and Beijing-You chickens) and at different periods from the perspective of immunoglobulin gene expression mechanism. We analyzed the diversity of immunoglobulin based on the results of high-throughput sequencing by extracting Fabricius bursa RNA, RACE (Rapid Amplification of cDNA Ends) technique, and constructing DNA libraries. Our study reveals that the junctional diversity, somatic hypermutation, CDR3 diversity, and gene conversion expression of immunoglobulins in Hy-line brown hens, Lueyang black-bone chickens, and Beijing-You chickens converge during the same time period. This indicates that the immunoglobulin gene expression mechanisms in different chicken breeds do not exhibit significant variations as a result of selective breeding.


Assuntos
Galinhas , Animais , Galinhas/genética , Galinhas/imunologia , Feminino , Imunoglobulinas/genética , Imunoglobulinas/metabolismo , Genes de Imunoglobulinas/genética
13.
Chemosphere ; 357: 141953, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38614395

RESUMO

The effects of culture filtrate of Alexandrium tamarense on Prorocentrum donghaiense and Heterosigma akashiwo were investigated, including determination of algal density, photosynthesis, intracellular enzyme content and activity. The filtrate of A. tamarense had a stronger inhibitory effect on P. donghaiense than H. akashiwo, and the inhibitory effect decreased with higher temperature treatment of the filtrate. Instantaneous fluorescence (Ft) and maximum quantum yield of photosystem II (Fv/Fm) values of both kinds of target algae were reduced as exposed to the filtrate of A. tamarense, which proved that allelopathy could inhibit the normal operation of photosynthetic system. The increase of Malondialdehyde (MDA) content of the two kinds of target algae indicated that the cell membrane was seriously damaged by allelochemicals released by A. tamarense. The different responses of Superoxide Dismutase (SOD) and Catalase (CAT) activity in two kinds of target algae demonstrated the complexity and diversity of allelopathic mechanism. The filtrate of A. tamarense also influenced the metabolic function (ATPases) of P. donghaiense and H. akashiwo, and the influence on P. donghaiense was greater. Liquid-liquid extraction was used to extract and isolate allelochemicals from the filtrate of A. tamarense. It was found that only component I with molecular weight of 424.2573 and 434.2857 could inhibit the growth of P. donghaiense by HPLC-MS.


Assuntos
Alelopatia , Catalase , Dinoflagellida , Malondialdeído , Feromônios , Fotossíntese , Dinoflagellida/fisiologia , Feromônios/farmacologia , Malondialdeído/metabolismo , Fotossíntese/efeitos dos fármacos , Catalase/metabolismo , Superóxido Dismutase/metabolismo , Complexo de Proteína do Fotossistema II/metabolismo
14.
ACS Nano ; 18(14): 9917-9928, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38548470

RESUMO

Single-walled carbon nanotube (SWCNT) films exhibit exceptional optical and electrical properties, making them highly promising for scalable integrated devices. Previously, we employed SWCNT films as templates for the chemical vapor deposition (CVD) synthesis of one-dimensional heterostructure films where boron nitride nanotubes (BNNTs) and molybdenum disulfide nanotubes (MoS2NTs) were coaxially nested over the SWCNT networks. In this work, we have further refined the synthesis method to achieve precise control over the BNNT coating in SWCNT@BNNT heterostructure films. The resulting structure of the SWCNT@BNNT films was thoroughly characterized using a combination of electron microscopy, UV-vis-NIR spectroscopy, Fourier-transform infrared (FT-IR) spectroscopy, and Raman spectroscopy. Specifically, we investigated the pressure effect induced by BNNT wrapping on the SWCNTs in the SWCNT@BNNT heterostructure film and demonstrated that the shifts of the SWCNT's G and 2D (G') modes in Raman spectra can be used as a probe of the efficiency of BNNT coating. In addition, we studied the impact of vacuum annealing on the removal of the initial doping in SWCNTs, arising from exposure to ambient atmosphere, and examined the effect of MoO3 doping in SWCNT films by using UV-vis-NIR spectroscopy and Raman spectroscopy. We show that through correlation analysis of the G and 2D (G') modes in Raman spectra, it is possible to discern distinct types of doping effects as well as the influence of applied pressure on the SWCNTs within SWCNT@BNNT heterostructure films. This work contributes to a deeper understanding of the strain and doping effect in both SWCNTs and SWCNT@BNNTs, thereby providing valuable insights for future applications of carbon-nanotube-based one-dimensional heterostructures.

15.
IEEE Trans Image Process ; 33: 1522-1533, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38373122

RESUMO

Current research on cross-modal retrieval is mostly English-oriented, as the availability of a large number of English-oriented human-labeled vision-language corpora. In order to break the limit of non-English labeled data, cross-lingual cross-modal retrieval (CCR) has attracted increasing attention. Most CCR methods construct pseudo-parallel vision-language corpora via Machine Translation (MT) to achieve cross-lingual transfer. However, the translated sentences from MT are generally imperfect in describing the corresponding visual contents. Improperly assuming the pseudo-parallel data are correctly correlated will make the networks overfit to the noisy correspondence. Therefore, we propose Dual-view Curricular Optimal Transport (DCOT) to learn with noisy correspondence in CCR. In particular, we quantify the confidence of the sample pair correlation with optimal transport theory from both the cross-lingual and cross-modal views, and design dual-view curriculum learning to dynamically model the transportation costs according to the learning stage of the two views. Extensive experiments are conducted on two multilingual image-text datasets and one video-text dataset, and the results demonstrate the effectiveness and robustness of the proposed method. Besides, our proposed method also shows a good expansibility to cross-lingual image-text baselines and a decent generalization on out-of-domain data.

16.
Innovation (Camb) ; 5(2): 100564, 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38379787

RESUMO

The type V-I CRISPR-Cas system is becoming increasingly more attractive for genome editing. However, natural nucleases of this system often exhibit low efficiency, limiting their application. Here, we used structure-guided rational design and protein engineering to optimize an uncharacterized Cas12i nuclease, Cas12i3. As a result, we developed Cas-SF01, a Cas12i3 variant that exhibits significantly improved gene editing activity in mammalian cells. Cas-SF01 shows comparable or superior editing performance compared to SpCas9 and other Cas12 nucleases. Compared to natural Cas12i3, Cas-SF01 has an expanded PAM range and effectively recognizes NTTN and noncanonical NATN and TTVN PAMs. In addition, we identified an amino acid substitution, D876R, that markedly reduced the off-target effect while maintaining high on-target activity, leading to the development of Cas-SF01HiFi (high-fidelity Cas-SF01). Finally, we show that Cas-SF01 has high gene editing activities in mice and plants. Our results suggest that Cas-SF01 can serve as a robust gene editing platform with high efficiency and specificity for genome editing applications in various organisms.

17.
Res Sq ; 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-38260587

RESUMO

As the first identified multidrug efflux pump in Mycobacterium tuberculosis (Mtb), EfpA is an essential protein and promising drug target. However, the functional and inhibitory mechanisms of EfpA are poorly understood. Herein we report cryo-EM structures of EfpA in outward-open conformation, either bound to three endogenous lipids or the inhibitor BRD-8000.3. Three lipids inside EfpA span from the inner leaflet to the outer leaflet of the membrane. BRD-8000.3 occupies one lipid site at the level of inner membrane leaflet, competitively inhibiting lipid binding. EfpA resembles the related lysophospholipid transporter MFSD2A in both overall structure and lipid binding sites, and may function as a lipid flippase. Combining AlphaFold-predicted EfpA structure, which is inward-open, we propose a complete conformational transition cycle for EfpA. Together, our results provide a structural and mechanistic foundation to comprehend EfpA function and develop EfpA-targeting anti-TB drugs.

18.
Chem Biodivers ; 21(3): e202301631, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38205915

RESUMO

Two undescribed protostane triterpenoids, 11-deoxy-13(17),15-dehydro-alisol B 23-acetate (2) and alisol S (3), together with 21 known ones (1, 4-23), were isolated from the dried rhizome of Alisma plantago-aquatica. Of these compounds, 13(17),15-Dehydro-alisol B 23-acetate (1) and 11-deoxy-13(17),15-dehydro-alisol B 23-acetate (2) are two protostane triterpenoids containing conjugated double bonds in the five-membered ring D that are rarely found from nature resource, while alisol S (3) is a protostane triterpenoid with undescribed tetrahydrofuran moiety linked via C20 -O-C24 at the side chain. Additionally, compound 18 is a new natural product, and cycloartenol triterpenoid 23 is a non protostane triterpenoid firstly isolated from genus Alisma. Their structures were elucidated by extensive spectral analysis of the UV, IR, MS, 1D and 2D NMR, and comparison of the experimental and calculated CD curves.


Assuntos
Alisma , Triterpenos , Alisma/química , Rizoma/química , Triterpenos/química , Extratos Vegetais/química , Espectroscopia de Ressonância Magnética
19.
Exp Anim ; 73(1): 83-92, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-37648521

RESUMO

The incidence of autoimmune hepatitis (AIH) has increased significantly worldwide. The present study aims to explore the protective effect of L-lysine supplementation against AIH and to investigate its potential underlying mechanisms. A chronic experimental AIH mouse model was established by repeated tail vein injection of human cytochrome P450 2D6 (CYP2D6) plasmid. Starting from day 14 of the modeling, mice in the CYP2D6-AIH +L-lysine group were given 200 µl of purified water containing 10 mg/kg L-lysine by gavage until day27, once a day, and mice in the healthy control group and model group were given an equal volume of purified water by gavage. Our results showed that L-lysine supplementation partially reversed the liver injury mediated by CYP2D6 overexpression. These effects were consistent with the restraining impacts of L-lysine supplementation on decreasing pro-inflammatory cytokines expression level and CD4+ and CD8+ T lymphocytes infiltration, as well as curbing hepatic oxidative stress. Furthermore, L-lysine supplement relieved liver fibrosis in the context of AIH. In conclusion, L-lysine supplementation attenuates CYP2D6-induced immune liver injury in mice, which may serve as a novel nutrition support approach for AIH.


Assuntos
Hepatite Autoimune , Camundongos , Humanos , Animais , Hepatite Autoimune/prevenção & controle , Hepatite Autoimune/etiologia , Lisina , Citocromo P-450 CYP2D6 , Modelos Animais de Doenças , Autoantígenos , Fígado/metabolismo , Suplementos Nutricionais , Água
20.
IEEE Trans Pattern Anal Mach Intell ; 46(2): 1049-1064, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37878438

RESUMO

Video captioning aims to generate natural language descriptions for a given video clip. Existing methods mainly focus on end-to-end representation learning via word-by-word comparison between predicted captions and ground-truth texts. Although significant progress has been made, such supervised approaches neglect semantic alignment between visual and linguistic entities, which may negatively affect the generated captions. In this work, we propose a hierarchical modular network to bridge video representations and linguistic semantics at four granularities before generating captions: entity, verb, predicate, and sentence. Each level is implemented by one module to embed corresponding semantics into video representations. Additionally, we present a reinforcement learning module based on the scene graph of captions to better measure sentence similarity. Extensive experimental results show that the proposed method performs favorably against the state-of-the-art models on three widely-used benchmark datasets, including microsoft research video description corpus (MSVD), MSR-video to text (MSR-VTT), and video-and-TEXt (VATEX).

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