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1.
Cell ; 143(1): 99-110, 2010 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-20887895

RESUMO

Auxin is a multifunctional hormone essential for plant development and pattern formation. A nuclear auxin-signaling system controlling auxin-induced gene expression is well established, but cytoplasmic auxin signaling, as in its coordination of cell polarization, is unexplored. We found a cytoplasmic auxin-signaling mechanism that modulates the interdigitated growth of Arabidopsis leaf epidermal pavement cells (PCs), which develop interdigitated lobes and indentations to form a puzzle-piece shape in a two-dimensional plane. PC interdigitation is compromised in leaves deficient in either auxin biosynthesis or its export mediated by PINFORMED 1 localized at the lobe tip. Auxin coordinately activates two Rho GTPases, ROP2 and ROP6, which promote the formation of complementary lobes and indentations, respectively. Activation of these ROPs by auxin occurs within 30 s and depends on AUXIN-BINDING PROTEIN 1. These findings reveal Rho GTPase-based auxin-signaling mechanisms, which modulate the spatial coordination of cell expansion across a field of cells.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/citologia , Arabidopsis/metabolismo , Proteínas de Ligação ao GTP/metabolismo , Ácidos Indolacéticos/metabolismo , Proteínas Monoméricas de Ligação ao GTP/metabolismo , Transdução de Sinais , Membrana Celular/metabolismo , Forma Celular , Folhas de Planta/citologia , Proteínas de Plantas/metabolismo , Receptores de Superfície Celular/metabolismo
2.
Curr Opin Oncol ; 36(4): 276-281, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38726812

RESUMO

PURPOSE OF REVIEW: There are numerous sarcoma subtypes and vary widely in terms of epidemiology, clinical characteristics, genetic profiles, and pathophysiology. They also differ widely between ethnic groups. This review focuses on the different incidence rates of sarcomas in different regions and the potential explanations for these disparities. RECENT FINDINGS: In an intercontinental study using national cancer registry databases from France and Taiwan, the French population had a higher risk of liposarcomas, leiomyosarcomas, and synovial sarcomas, whereas the Taiwanese population had a higher incidence of angiosarcomas and malignant peripheral nerve sheath tumors. The anatomical distribution of these sarcomas also varied between these two regions. In France, most angiosarcoma cases occurred in the extremities and trunk, whereas in Taiwan, angiosarcoma cases in the abdomen and pelvis were more common. Another international study showed that in addition to the common known TP53 and NF1 germline mutations, genes involved in centromere and telomere maintenance were also involved in sarcomagenesis. We reviewed factors related to genetics, environmental effects, chemical exposure, and radiation exposure that could explain the differences in sarcoma incidence among different geographical or ethnic regions. SUMMARY: Our understanding of the potential cause of sarcomas with different subtypes is limited. Establishing a comprehensive global database for patients with sarcomas from all ethnic groups is essential to deepen our understanding of the potential risk factors and the pathophysiology of all sarcoma subtypes.


Assuntos
Sarcoma , Humanos , Saúde Global , Incidência , Sarcoma/epidemiologia , Sarcoma/genética , Sarcoma/patologia , Taiwan/epidemiologia , França/epidemiologia
3.
J Biomed Sci ; 31(1): 69, 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38992696

RESUMO

BACKGROUND: Local translation at synapses is important for rapidly remodeling the synaptic proteome to sustain long-term plasticity and memory. While the regulatory mechanisms underlying memory-associated local translation have been widely elucidated in the postsynaptic/dendritic region, there is no direct evidence for which RNA-binding protein (RBP) in axons controls target-specific mRNA translation to promote long-term potentiation (LTP) and memory. We previously reported that translation controlled by cytoplasmic polyadenylation element binding protein 2 (CPEB2) is important for postsynaptic plasticity and memory. Here, we investigated whether CPEB2 regulates axonal translation to support presynaptic plasticity. METHODS: Behavioral and electrophysiological assessments were conducted in mice with pan neuron/glia- or glutamatergic neuron-specific knockout of CPEB2. Hippocampal Schaffer collateral (SC)-CA1 and temporoammonic (TA)-CA1 pathways were electro-recorded to monitor synaptic transmission and LTP evoked by 4 trains of high-frequency stimulation. RNA immunoprecipitation, coupled with bioinformatics analysis, were used to unveil CPEB2-binding axonal RNA candidates associated with learning, which were further validated by Western blotting and luciferase reporter assays. Adeno-associated viruses expressing Cre recombinase were stereotaxically delivered to the pre- or post-synaptic region of the TA circuit to ablate Cpeb2 for further electrophysiological investigation. Biochemically isolated synaptosomes and axotomized neurons cultured on a microfluidic platform were applied to measure axonal protein synthesis and FM4-64FX-loaded synaptic vesicles. RESULTS: Electrophysiological analysis of hippocampal CA1 neurons detected abnormal excitability and vesicle release probability in CPEB2-depleted SC and TA afferents, so we cross-compared the CPEB2-immunoprecipitated transcriptome with a learning-induced axonal translatome in the adult cortex to identify axonal targets possibly regulated by CPEB2. We validated that Slc17a6, encoding vesicular glutamate transporter 2 (VGLUT2), is translationally upregulated by CPEB2. Conditional knockout of CPEB2 in VGLUT2-expressing glutamatergic neurons impaired consolidation of hippocampus-dependent memory in mice. Presynaptic-specific ablation of Cpeb2 in VGLUT2-dominated TA afferents was sufficient to attenuate protein synthesis-dependent LTP. Moreover, blocking activity-induced axonal Slc17a6 translation by CPEB2 deficiency or cycloheximide diminished the releasable pool of VGLUT2-containing synaptic vesicles. CONCLUSIONS: We identified 272 CPEB2-binding transcripts with altered axonal translation post-learning and established a causal link between CPEB2-driven axonal synthesis of VGLUT2 and presynaptic translation-dependent LTP. These findings extend our understanding of memory-related translational control mechanisms in the presynaptic compartment.


Assuntos
Plasticidade Neuronal , Proteínas de Ligação a RNA , Transmissão Sináptica , Proteína Vesicular 2 de Transporte de Glutamato , Animais , Camundongos , Proteínas de Ligação a RNA/metabolismo , Proteínas de Ligação a RNA/genética , Plasticidade Neuronal/fisiologia , Transmissão Sináptica/fisiologia , Proteína Vesicular 2 de Transporte de Glutamato/metabolismo , Proteína Vesicular 2 de Transporte de Glutamato/genética , Camundongos Knockout , Axônios/metabolismo , Axônios/fisiologia , RNA Mensageiro/metabolismo , RNA Mensageiro/genética , Masculino , Biossíntese de Proteínas
4.
Am J Emerg Med ; 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-39097519

RESUMO

As the landscape becomes more urbanized, snakebites have increasingly become uncommon presentations to the emergency departments in Singapore, while snakebites causing significant envenomation are even rarer. In this case report, we discuss a 55-year-old man who had significant envenomation from a Shore Pit Viper (Trimeresurus Purpureomaculatus) and who was successfully treated with haemato-toxic polyvalent antivenom (HPAV). He initially presented with pain, swelling and bleeding over his wound. Due to a deterioration in his coagulation profile, he was given two doses of HPAV which is typically reserved for viperid snakes instead. Following administration of the anti-venom, the patient's coagulation profile improved, and the local soft tissue effects of the venom resolved. He did not manifest any adverse effects and was discharged uneventfully about 72 h after the snakebite. The cross-neutralization potential of HPAV for Shore Pit Viper (Trimeresurus Purpureomaculatus) venom in this case study suggests that there may be a possible common underlying chemical structure and pathophysiology among the venom proteins of various snake species. Given that Trimeresurus-specific antivenom is unavailable in most countries, this cross-neutralization strategy deserves further consideration and evaluation in similar circumstances.

5.
BMC Nurs ; 23(1): 151, 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38439062

RESUMO

BACKGROUND: The informal caregivers of adult patients with ß-thalassemia major (ß-TM) bear not only physical but also emotional and economic pressures of providing care. This study is the first to evaluate the caregiver burden by Zarit Burden Interview (ZBI) of adult patients with ß-TM in mainland China and to identify predictors of caregiver burden. METHODS: In this cross-sectional study, we conducted an online survey with snowball sampling covering seven provinces between September 1, 2021, and January 31, 2022, of patients aged ≥ 18 years with ß-TM and their informal caregivers. Caregiver burden was assessed using the ZBI. Data on patient demographics, disease and therapy characteristics, and informal caregivers' demographic characteristics were collected and analysed using independent t-tests, analysis of variance, Spearman's correlation and multiple linear regression. RESULTS: Of 75 included patients, more than half (50.7%) were male. The mean patient age was 24.69 ± 5.59 years. The mean age of the informal caregivers was 50.60 ± 9.16 years, with women (74.7%) being predominant. The ZBI score was 38.00 ± 17.02. Multiple linear regression analysis showed that patients with interrupted blood transfusion therapy and informal caregivers required to care of others were positively associated with caregiver burden (p < 0.05). Age of informal caregivers were borderline significant positively associated with caregiver burden (p < 0.1). Married informal caregivers were negatively associated with caregiver burden (p < 0.05). CONCLUSIONS: The informal caregivers of adult patients with ß-TM in mainland China experienced a moderate-to-severe level of caregiving burden. The caregiver burden was higher in patients with a history of interrupted blood transfusion therapy or in informal caregivers who were older or needed to care for others. Additionally, married informal caregivers experienced lower burdens compared to non-married informal caregivers. These findings provide a reference to identify informal caregivers with higher burdens among patients with ß-TM.

6.
Zhongguo Zhong Yao Za Zhi ; 49(9): 2532-2543, 2024 May.
Artigo em Zh | MEDLINE | ID: mdl-38812149

RESUMO

This study employed knowledge graph technology to analyze the research status and hot spots of Realgar and provide guidance for clinical application and further research of this drug. The research articles both in English and Chinese involving Realgar were retrieved from five databases including CNKI, Wanfang, VIP, SinoMed, and Web of Science. And NoteExpress, a literature management software was used to screen literature. CiteSpace was utilized for visualized analysis and presentations of the authors, institutions, and keywords. 2 879 articles in Chinese and 194 articles in English were included. China Journal of Chinese Materia Medica and Journal of Ethnopharmacology were the top Chinese and English journals in terms of publication volume. Realgar is widely used in the treatment of skin diseases, blood diseases, and cancer. JIANG Hong was the author who have published more articles in Chinese and English working with teams. School of Public Health of China Medical University and China Academy of Chinese Medical Sciences published the most articles in Chinese and English. The research on Realgar mainly focuses on clinical application, mechanism of action, reduction of toxicity, and enhancement of efficacy. The authors and institutions of Realgar research are mainly concentrated in China. The study on the mechanism of treating hematological diseases and cancer with Realgar, as well as the research on its effects of reducing toxicity and enhancing efficacy, are the current research hotspots. The mechanism of "same treatment for different diseases" in Realgar needs to be further explored. It is urgent to carry out interdisciplinary research on Realgar. This study can provide a refe-rence for the clinical application of Realgar and provide ideas for further research on Realgar.


Assuntos
Arsenicais , Sulfetos , Humanos , Arsenicais/química , China , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/uso terapêutico , Pesquisa Biomédica
7.
Plant Cell Environ ; 46(8): 2558-2574, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37267124

RESUMO

Sweet potato (Ipomoea batatas) is an important tuber crop, but also target of numerous insect pests. Intriguingly, the abundant storage protein in tubers, sporamin, has intrinsic trypsin protease inhibitory activity. In leaves, sporamin is induced by wounding or a volatile homoterpene and enhances insect resistance. While the signalling pathway leading to sporamin synthesis is partially established, the initial event, perception of a stress-related signal is still unknown. Here, we identified an IbLRR-RK1 that is induced upon wounding and herbivory, and related to peptide-elicitor receptors (PEPRs) from tomato and Arabidopsis. We also identified a gene encoding a precursor protein comprising a peptide ligand (IbPep1) for IbLRR-RK1. IbPep1 represents a distinct signal in sweet potato, which might work in a complementary and/or parallel pathway to the previously described hydroxyproline-rich systemin (HypSys) peptides to strengthen insect resistance. Notably, an interfamily compatibility in the Pep/PEPR system from Convolvulaceae and Solanaceae was identified.


Assuntos
Ipomoea batatas , Ipomoea batatas/genética , Ipomoea batatas/metabolismo , Ligantes , Proteínas de Plantas/metabolismo , Regulação da Expressão Gênica de Plantas , Peptídeos/metabolismo
8.
Org Biomol Chem ; 21(38): 7808-7812, 2023 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-37718644

RESUMO

Based on the correlation between inflammation and reactive oxygen species and viscosity, a fluorescent probe (SWJT-19) was designed for a relay detection of hypochlorite ions and viscosity. The synthesized probe could quickly and selectively detect hypochlorite ions, as well as viscosity of the system effectively. Moreover, the probe had been successfully applied to sequentially detect hypochlorite ions and viscosity in organisms, as well as imaging in mouse inflammation.

9.
Phys Chem Chem Phys ; 25(47): 32421-32429, 2023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-37782052

RESUMO

The experimental C 1s near-edge X-ray absorption fine-structure (NEXAFS) spectra of graphdiyne (GDY) show an evident change at different exposure periods, which is explained by oxidation. Herein, to better understand the structure-spectra relationship and the influence of oxidization, we performed a first-principles simulation of the NEXAFS spectra and X-ray photoelectron spectra (XPS) of both pure GDY and its four typical graphdiyne oxides (GDO) at the carbon K-edge. Pure GDY contains one sp2-hybridized (C1) and two sp-hybridized (C2, C3) carbons, while oxidation introduces more nonequivalent carbons. The experimental NEXAFS spectrum exhibits the lowest peak at ca. 285.8 eV. It was found that the C 1s → π* excitation from the sp2-hybridized carbon atoms (C1) in pure GDY and the sp-hybridized atoms (C2, C3) in GDOs contributes to this peak. The two weak resonances at around 289.0 and 290.6 eV in the experiment are contributed by the carbon atoms bonded to the oxygen atoms. Meanwhile, we found that oxidization leads to an increase in the C 1s ionization potentials (IPs) by 0.3-2.7 eV, which is consistent with the XPS experiments. Our calculations provide a clear explanation of the structure-spectra relationships of GDY and GDOs, and the signatures are useful for estimating the degree of oxidation.

10.
Phys Chem Chem Phys ; 25(27): 18387-18399, 2023 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-37401358

RESUMO

Single-molecule magnets (SMMs) have great potential in becoming revolutionary materials for micro-electronic devices. As one type of SMM and holding the performance record, lanthanide single-ion magnets (Ln-SIMs) stand at the forefront of the family. Lowering the coordination number (CN) is an important strategy to improve the performance of Ln-SIMs. Here, we report a theoretical study on a typical group of low-CN Ln-SIMs, i.e., tetracoordinated structures. Our results are consistent with those of experiments and they identify the same three best Ln-SIMs via a concise criterion, i.e., the co-existence of long τQTM and high Ueff. Compared to the record-holding dysprosocenium systems, the best SIMs here possess τQTM values that are shorter by several orders of magnitude and Ueff values that are lower by ∼1000 Kelvin (K). These are important reasons for the fact that the tetracoordinated Ln-SIMs are clearly inferior to dysprosocenium. A simple but intuitive crystal-field analysis leads to several routes to improve the performance of a given Ln-SIM, including compression of the axial bond length, widening the axial bond angle, elongation of the equatorial bond length and usage of weaker equatorial donor ligands. Although these routes are not brand-new, the most efficient option and the degree of improvement resulting from it are not known in advance. Consequently, a theoretical magneto-structural study, covering various routes, is carried out for the best Ln-SIM here and the most efficient route is shown to be widening the axial ∠O-Dy-O angle. The most optimistic case, having a ∠O-Dy-O of 180°, could have a τQTM (up to 103 s) and Ueff (∼2400 K) close to those of the record-holders. Subsequently, a blocking temperature (TB) of 64 K is predicted to be possible for it. A more practical case, with ∠O-Dy-O being 160°, could have a τQTM of up to 400 s, Ueff of around 2200 K and the possibility of a TB of 57 K. Although having an inherent precision limit, these predictions provide a guide to performance improvement, starting from an existing system.

11.
J Ind Microbiol Biotechnol ; 50(1)2023 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-37580133

RESUMO

Astaxanthin has high utilization value in functional food because of its strong antioxidant capacity. However, the astaxanthin content of Phaffia rhodozyma is relatively low. Adaptive laboratory evolution is an excellent method to obtain high-yield strains. TiO2 is a good inducer of oxidative stress. In this study, different concentrations of TiO2 were used to domesticate P. rhodozyma, and at a concentration of 1000 mg/L of TiO2 for 105 days, the optimal strain JMU-ALE105 for astaxanthin production was obtained. After fermentation, the astaxanthin content reached 6.50 mg/g, which was 41.61% higher than that of the original strain. The ALE105 strain was fermented by batch and fed-batch, and the astaxanthin content reached 6.81 mg/g. Transcriptomics analysis showed that the astaxanthin synthesis pathway, and fatty acid, pyruvate, and nitrogen metabolism pathway of the ALE105 strain were significantly upregulated. Based on the nitrogen metabolism pathway, the nitrogen source was adjusted by ammonium sulphate fed-batch fermentation, which increased the astaxanthin content, reaching 8.36 mg/g. This study provides a technical basis and theoretical research for promoting industrialization of astaxanthin production of P. rhodozyma. ONE-SENTENCE SUMMARY: A high-yield astaxanthin strain (ALE105) was obtained through TiO2 domestication, and its metabolic mechanism was analysed by transcriptomics, which combined with nitrogen source regulation to further improve astaxanthin yield.


Assuntos
Xantofilas , Evolução Molecular Direcionada , Perfilação da Expressão Gênica , Basidiomycota/química , Basidiomycota/classificação , Basidiomycota/genética , Basidiomycota/crescimento & desenvolvimento , Biomassa , Glucose/análise , Carotenoides/análise , Fermentação , Técnicas de Cultura Celular por Lotes , Nitrogênio/metabolismo , Xantofilas/química , Xantofilas/metabolismo
12.
Eur Spine J ; 32(12): 4220-4228, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37237239

RESUMO

PURPOSE: The aim is to compare the pathogen detection performance of metagenomic next-generation sequencing (mNGS) and the culturing of percutaneous needle biopsy samples obtained from an individual with a suspected spinal infection. METHODS: A retrospective study of 141 individuals with a suspected spinal infection was conducted, and mNGS was performed. The microbial spectra and detection performance between mNGS and the culturing-based method were compared, and the effects of antibiotic intervention and biopsy on the detection performance were assessed. RESULTS: The microorganisms isolated most commonly via the culturing-based method were Mycobacterium tuberculosis (n = 21), followed by Staphylococcus epidermidis (n = 13). The most common microorganisms detected via mNGS were Mycobacterium tuberculosis complex (MTBC) (n = 39), followed by Staphylococcus aureus (n = 15). The difference in the type of detected microorganisms between culturing and mNGS was observed only in Mycobacterium (P = 0.001). mNGS helped identify potential pathogens in 80.9% of cases, which was significantly higher than the positivity rate of 59.6% observed for the culturing-based method (P < 0.001). Moreover, mNGS had a sensitivity of 85.7% (95% CI, 78.4% to 91.3%), a specificity of 86.7% (95% CI, 59.5% to 98.3%), and sensitivity gains of 35% (85.7% vs. 50.8%; P < 0.001) during culturing, while no differences were observed in the specificity (86.7% vs. 93.3%; P = 0.543). In addition, antibiotic interventions significantly lowered the positivity rate of the culturing-based method (66.0% vs. 45.5%, P = 0.021) but had no effects on the results of mNGS (82.5% vs. 77.3%, P = 0.467). CONCLUSION: The use of mNGS could result in a higher detection rate compared to that observed with the culturing-based method in an individual with spinal infection and is particularly valuable for evaluating the effects of a mycobacterial infection or previous antibiotic intervention.


Assuntos
Sequenciamento de Nucleotídeos em Larga Escala , Mycobacterium tuberculosis , Humanos , Estudos Retrospectivos , Antibacterianos , Biópsia , Mycobacterium tuberculosis/genética , Sensibilidade e Especificidade
13.
BMC Med Inform Decis Mak ; 23(1): 142, 2023 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-37507752

RESUMO

PURPOSE: With the in-depth application of machine learning(ML) in clinical practice, it has been used to predict the mortality risk in patients with traumatic brain injuries(TBI). However, there are disputes over its predictive accuracy. Therefore, we implemented this systematic review and meta-analysis, to explore the predictive value of ML for TBI. METHODOLOGY: We systematically retrieved literature published in PubMed, Embase.com, Cochrane, and Web of Science as of November 27, 2022. The prediction model risk of bias(ROB) assessment tool (PROBAST) was used to assess the ROB of models and the applicability of reviewed questions. The random-effects model was adopted for the meta-analysis of the C-index and accuracy of ML models, and a bivariate mixed-effects model for the meta-analysis of the sensitivity and specificity. RESULT: A total of 47 papers were eligible, including 156 model, with 122 newly developed ML models and 34 clinically recommended mature tools. There were 98 ML models predicting the in-hospital mortality in patients with TBI; the pooled C-index, sensitivity, and specificity were 0.86 (95% CI: 0.84, 0.87), 0.79 (95% CI: 0.75, 0.82), and 0.89 (95% CI: 0.86, 0.92), respectively. There were 24 ML models predicting the out-of-hospital mortality; the pooled C-index, sensitivity, and specificity were 0.83 (95% CI: 0.81, 0.85), 0.74 (95% CI: 0.67, 0.81), and 0.75 (95% CI: 0.66, 0.82), respectively. According to multivariate analysis, GCS score, age, CT classification, pupil size/light reflex, glucose, and systolic blood pressure (SBP) exerted the greatest impact on the model performance. CONCLUSION: According to the systematic review and meta-analysis, ML models are relatively accurate in predicting the mortality of TBI. A single model often outperforms traditional scoring tools, but the pooled accuracy of models is close to that of traditional scoring tools. The key factors related to model performance include the accepted clinical variables of TBI and the use of CT imaging.


Assuntos
Lesões Encefálicas Traumáticas , Humanos , Lesões Encefálicas Traumáticas/diagnóstico , Sensibilidade e Especificidade , Análise Multivariada , Mortalidade Hospitalar , Aprendizado de Máquina
14.
J Biol Chem ; 296: 100052, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33168624

RESUMO

Microsomal triglyceride transfer protein (MTTP) is an endoplasmic reticulum resident protein that is essential for the assembly and secretion of triglyceride (TG)-rich, apoB-containing lipoproteins. Although the function and structure of mammalian MTTP have been extensively studied, how exactly MTTP transfers lipids to lipid acceptors and whether there are other biomolecules involved in MTTP-mediated lipid transport remain elusive. Here we identify a role in this process for the poorly characterized protein PRAP1. We report that PRAP1 and MTTP are partially colocalized in the endoplasmic reticulum. We observe that PRAP1 directly binds to TG and facilitates MTTP-mediated lipid transfer. A single amino acid mutation at position 85 (E85V) impairs PRAP1's ability to form a ternary complex with TG and MTTP, as well as impairs its ability to facilitate MTTP-mediated apoB-containing lipoprotein assembly and secretion, suggesting that the ternary complex formation is required for PRAP1 to facilitate MTTP-mediated lipid transport. PRAP1 is detectable in chylomicron/VLDL-rich plasma fractions, suggesting that MTTP recognizes PRAP1-bound TG as a cargo and transfers TG along with PRAP1 to lipid acceptors. Both PRAP1-deficient and E85V knock-in mutant mice fed a chow diet manifested an increase in the length of their small intestines, likely to compensate for challenges in absorbing lipid. Interestingly, both genetically modified mice gained significantly less body weight and fat mass when on high-fat diets compared with littermate controls and were prevented from hepatosteatosis. Together, this study provides evidence that PRAP1 plays an important role in MTTP-mediated lipid transport and lipid absorption.


Assuntos
Proteínas de Transporte/metabolismo , Metabolismo dos Lipídeos , Proteínas da Gravidez/metabolismo , Animais , Apolipoproteína B-100/genética , Apolipoproteína B-100/metabolismo , Transporte Biológico , Dieta Hiperlipídica , Fígado Gorduroso/genética , Lipoproteínas/metabolismo , Camundongos , Camundongos Knockout , Proteínas da Gravidez/genética , Ligação Proteica , Triglicerídeos/metabolismo
15.
EMBO J ; 37(19)2018 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-30068531

RESUMO

Lipoprotein lipase (LPL) is a secreted lipase that clears triglycerides from the blood. Proper LPL folding and exit from the endoplasmic reticulum (ER) require lipase maturation factor 1 (LMF1), an ER-resident transmembrane protein, but the mechanism involved is unknown. We used proteomics to identify LMF1-binding partners necessary for LPL secretion in HEK293 cells and found these to include oxidoreductases and lectin chaperones, suggesting that LMF1 facilitates the formation of LPL's five disulfide bonds. In accordance with this role, we found that LPL aggregates in LMF1-deficient cells due to the formation of incorrect intermolecular disulfide bonds. Cells lacking LMF1 were hypersensitive to depletion of glutathione, but not DTT treatment, suggesting that LMF1 helps reduce the ER Accordingly, we found that loss of LMF1 results in a more oxidized ER Our data show that LMF1 has a broader role than simply folding lipases, and we identified fibronectin and the low-density lipoprotein receptor (LDLR) as novel LMF1 clients that contain multiple, non-sequential disulfide bonds. We conclude that LMF1 is needed for secretion of some ER client proteins that require reduction of non-native disulfides during their folding.


Assuntos
Retículo Endoplasmático/metabolismo , Homeostase , Proteínas de Membrana/metabolismo , Dobramento de Proteína , Dissulfetos/metabolismo , Retículo Endoplasmático/genética , Fibronectinas/genética , Fibronectinas/metabolismo , Glutationa/genética , Glutationa/metabolismo , Células HEK293 , Humanos , Lipase Lipoproteica/genética , Lipase Lipoproteica/metabolismo , Proteínas de Membrana/genética , Oxirredução , Proteômica , Receptores de LDL/genética , Receptores de LDL/metabolismo
16.
Hepatology ; 74(2): 776-796, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33619771

RESUMO

BACKGROUND AND AIMS: HCC undergoes active metabolic reprogramming. Reactive oxygen species (ROS) are excessively generated in cancer cells and are neutralized by NADPH. Malic enzymes (MEs) are the less studied NADPH producers in cancer. APPROACH AND RESULTS: We found that ME1, but not ME3, was regulated by the typical oxidative stress response pathway mediated by kelch-like ECH associated protein 1/nuclear factor erythroid 2-related factor (NRF2). Surprisingly, ME3 was constitutively induced by superenhancers. Disruption of any ME regulatory pathways decelerated HCC progression and sensitized HCC to sorafenib. Therapeutically, simultaneous blockade of NRF2 and a superenhancer complex completely impeded HCC growth. We show that superenhancers allow cancer cells to counteract the intrinsically high level of ROS through constitutively activating ME3 expression. When HCC cells encounter further episodes of ROS insult, NRF2 allows cancer cells to adapt by transcriptionally activating ME1. CONCLUSIONS: Our study reveals the complementary regulatory mechanisms which control MEs and provide cancer cells multiple layers of defense against oxidative stress. Targeting both regulatory mechanisms represents a potential therapeutic approach for HCC treatment.


Assuntos
Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Malato Desidrogenase/genética , Álcool Oxidorredutases Dependentes de NAD(+) e NADP(+)/genética , Fator 2 Relacionado a NF-E2/metabolismo , Animais , Carcinoma Hepatocelular/genética , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Hepatócitos , Humanos , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Neoplasias Hepáticas/genética , Malato Desidrogenase/metabolismo , Metabolômica , Camundongos , Álcool Oxidorredutases Dependentes de NAD(+) e NADP(+)/metabolismo , Estresse Oxidativo/genética , Espécies Reativas de Oxigênio/metabolismo , Ativação Transcricional , Ensaios Antitumorais Modelo de Xenoenxerto
17.
J Natl Compr Canc Netw ; 20(8): 906-914.e10, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35948040

RESUMO

BACKGROUND: We sought to identify the absolute risk of specific HPV genotype for cervical intraepithelial neoplasia grade 2/3 or worse (CIN2+/3+) and to develop a risk-based management strategy in an HPV-positive population. METHODS: HPV genotyping was performed based on a 3-year cervical cancer screening cohort. The study endpoints were histologic CIN2+/3+. The prevalence of specific HPV genotype was calculated by minimum, any type, and hierarchical attribution estimate. The absolute CIN2+/3+ risks of specific HPV genotype were estimated and risk-based management strategy was established according to the American Society for Colposcopy and Cervical Pathology guideline. The efficacy of conventional and risk-based management strategies for non-16/18 HPVs were further evaluated. RESULTS: Eligible data were available for 8,370 women with a median age of 48 years (interquartile range, 42-53 years). At baseline, there were 1,062 women with HPV-positive disease, including 424 with multiple and 639 with single infections. CIN2+/3+ cases represented 113/74, 23/8, 20/7, and 52/31 patients at baseline and first-, second-, and third-year visits, respectively. Women with multiple HPV infections at baseline were more prone to persistent infection than those with single infection (P<.0001). HPV16 and HPV52 were the top 2 ranking among baseline and 3-year cumulative CIN2+/3+ cases. Based on the absolute risk of specific HPV genotype combined with cytology for CIN2+/3+, all non-16/18 HPVs were divided into 4 risk-stratified groups. Compared with conventional strategy, the risk-based strategy had higher specificity (P=.0000) and positive predictive value (P=.0322) to detect CIN3+ and needed fewer colposcopies for each CIN3+ case. CONCLUSIONS: Based on our study findings, we propose a new extended HPV genotyping protocol, which would provide a better strategy for achieving precise risk-based management of HPV-positive populations.


Assuntos
Infecções por Papillomavirus , Displasia do Colo do Útero , Neoplasias do Colo do Útero , Adulto , Estudos de Coortes , Detecção Precoce de Câncer/métodos , Feminino , Genótipo , Humanos , Pessoa de Meia-Idade , Papillomaviridae/genética , Infecções por Papillomavirus/complicações , Infecções por Papillomavirus/diagnóstico , Infecções por Papillomavirus/epidemiologia , Medição de Risco , Neoplasias do Colo do Útero/diagnóstico , Neoplasias do Colo do Útero/epidemiologia , Neoplasias do Colo do Útero/patologia , Displasia do Colo do Útero/diagnóstico , Displasia do Colo do Útero/epidemiologia , Displasia do Colo do Útero/patologia
18.
Antonie Van Leeuwenhoek ; 115(6): 773-782, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35396624

RESUMO

A Gram-stain-positive, orange-pigmented, rod-shaped and flagellated bacterial strain T12T was isolated from wetland soil in Kunyu Mountain Wetland in Yantai, China. The strain was able to grow at 15-40 °C (optimum 37 °C), at 0.0-9.0% NaCl (optimum 2%, w/v) and at pH 5.5-9.0 (optimum 8.5). A phylogenetic analysis based on the 16S rRNA gene sequence indicated that strain T12T is a member of the family Planococcaceae, sharing 97.6% and 97.1% sequence similarity with the type strains of Jeotgalibacillus salarius and Jeotgalibacillus marinus, respectively. Genome-based analyses revealed a genome size of 3,506,682 bp and a DNA G + C content of 43.7%. Besides, the genome sequence led to 55.0-74.6% average amino acid identity values and 67.8-74.7% average nucleotide identity values between strain T12T and the current closest relatives. Digital DNA-DNA hybridization of strain T12T with the type strains of Jeotgalibacillus proteolyticus and J. marinus demonstrated 19.0% and 20.3% relatedness, respectively. The chemotaxonomic analysis showed that the sole quinone was MK-7. The predominant cellular fatty acids were iso-C15:0, anteiso-C15:0, C16:1ω7c alcohol and iso-C14:0. The polar lipids consisted of an unidentified aminolipid, phosphatidylglycerol, diphosphatidylglycerol and two unidentified phospholipids. Based on the polyphasic characterization, strain T12T is considered to represent a novel species, for which the name Jeotgalibacillus aurantiacus sp. nov. is proposed. The type strain is T12T (= KCTC 43296 T = MCCC 1K07171T).


Assuntos
Citrus sinensis , Planococáceas , Técnicas de Tipagem Bacteriana , Carotenoides , China , Citrus sinensis/genética , DNA Bacteriano/genética , Ácidos Graxos/química , Família Multigênica , Fosfolipídeos/química , Filogenia , Planococáceas/genética , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Solo , Áreas Alagadas
19.
J Clin Lab Anal ; 36(2): e24232, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34995016

RESUMO

BACKGROUND: Combined biomarkers can improve the sensitivity and specificity of ovarian cancer (OC) diagnosis and effectively predict patient prognosis. This study explored the diagnostic and prognostic values of serum CCL18 and CXCL1 antigens combined with C1D, FXR1, ZNF573, and TM4SF1 autoantibodies in OC. METHODS: CCL18 and CXCL1 monoclonal antibodies and C1D, FXR1, ZNF573, and TM4SF1 antigens were coated with microspheres. Logistic regression was used to construct a serum antigen-antibody combined detection model; receiver-operating characteristic curve (ROC) was used to evaluate the diagnostic efficacy of the model; and the Kaplan-Meier method and Cox regression models were used for survival analysis to evaluate the prognosis of OC. Data from The Cancer Genome Atlas (TCGA) and Genotype-Tissue Expression (GTEx) projects and online survival analysis tools were used to evaluate prognostic genes for OC. The CIBERSORT immune score was used to explore the factors influencing prognosis and their relationship with tumor-infiltrating immune cells. RESULTS: The levels of each index in the blood samples of patients with OC were higher than those of the other groups. The combined detection model has higher specificity and sensitivity in the diagnosis of OC, and its diagnostic efficiency is better than that of CA125 alone and diagnosing other malignant tumors. CCL18 and TM4SF1 may be factors affecting the prognosis of OC, and CCL18 may be related to immune-infiltrating cells. CONCLUSIONS: The serum antigen-antibody combined detection model established in this study has high sensitivity and specificity for the diagnosis of OC.


Assuntos
Autoanticorpos/sangue , Biomarcadores Tumorais/sangue , Quimiocina CXCL1/sangue , Quimiocinas CC/sangue , Neoplasias Ovarianas/diagnóstico , Antígenos de Superfície/imunologia , Proteínas Correpressoras/imunologia , Feminino , Humanos , Imunoglobulina G/sangue , Proteínas de Neoplasias/imunologia , Prognóstico , Proteínas de Ligação a RNA/imunologia , Valores de Referência , Sensibilidade e Especificidade
20.
Mar Drugs ; 20(12)2022 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-36547900

RESUMO

Most reports on signal peptides focus on their ability to affect the normal folding of proteins, thereby affecting their secreted expression, while few studies on its effects on enzymatic properties were published. Therefore, biochemical characterization and comparison of alginate lyase rALYI1/rALYI1-1 (rALYI1: without signal peptides; rALYI1-1:with signal peptides) were conducted in our study, and the results showed that the signal peptide affected the biochemical properties, especially in temperature and pH. rALYI1 (32.15 kDa) belonging to polysaccharide lyase family 7 was cloned from sea-cucumber-gut bacterium Tamlana sp. I1. The optimum temperature of both rALYI1 and rALYI1-1 was 40 °C, but the former had a wider optimum temperature range and better thermal stability. The optimum pH of rALYI1 and rALYI1-1 were 7.6 and 8.6, respectively. The former was more stable and acid resistant. Noticeably, rALYI1 was a salt-activated enzyme and displayed remarkable salt tolerance. Alginate, an essential polysaccharide in algae and Pseudomonas aeruginosa biofilms, is composed of α-L-guluronate and ß-D-mannuronate. It is also found in our study that rALYI1 is also effective in removing mature biofilms compared with controls. In conclusion, the signal peptide affects several biochemical properties of the enzyme, and alginate lyase rALYI1 may be an effective method for inhibiting biofilm formation of Pseudomonas aeruginosa.


Assuntos
Biofilmes , Flavobacteriaceae , Polissacarídeo-Liases , Sinais Direcionadores de Proteínas , Pseudomonas aeruginosa , Alginatos/química , Alginatos/metabolismo , Biofilmes/efeitos dos fármacos , Concentração de Íons de Hidrogênio , Polissacarídeo-Liases/química , Polissacarídeo-Liases/farmacologia , Pseudomonas aeruginosa/fisiologia , Especificidade por Substrato , Flavobacteriaceae/enzimologia
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