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1.
BMC Psychiatry ; 24(1): 179, 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38439012

RESUMO

BACKGROUND: People with schizophrenia often face challenges such as lower psychological resilience, reduced self-worth, and increased social stigma, hindering their recovery. Mindfulness-Based Cognitive Therapy (MBCT) has shown promise in boosting psychological resilience and self-esteem while diminishing stigma. However, MBCT demands professional involvement and substantial expenses, adding to the workload of professionals and the financial strain on patients. Mixed-mode Mindfulness-Based Cognitive Therapy (M-MBCT) integrates both "face-to-face" and "self-help" approaches to minimize staff effort and costs. This study aims to assess the impact of M-MBCT on the psychological resilience, self-esteem, and stigma in schizophrenia patients. METHODS: This randomized, controlled, parallel-group, assessor-blinded clinical trial enrolled 174 inpatients with schizophrenia. Participants were randomly assigned to either the experimental or control group. The experimental group underwent an 8-week M-MBCT intervention, while the control group received standard treatment. Data collection employed the Connor-Davidson Resilience Scale (CD-RISC), Internalized Stigma of Mental Illness Scale (ISMI), and Rosenberg Self-Esteem Scale (RSES) before and after the intervention. Post-intervention, significant differences in ISMI, CD-RISC, and RSES scores were observed between the experimental and control groups. RESULTS: In the experimental group, ISMI scores notably decreased, while CD-RISC and RSES scores significantly increased (P < 0.05). Multiple linear regression analysis identified age, education, and family history of mental illness as significant factors related to stigma (P < 0.05). Additionally, correlation analysis indicated a significant negative relationship between the reduction in CD-RISC scores and the reduction in ISMI scores (P < 0.05). CONCLUSION: M-MBCT effectively enhanced psychological resilience and self-esteem while diminishing stigma in individuals with schizophrenia. M-MBCT emerges as a promising treatment option for schizophrenia sufferers. TRIAL REGISTRATION: The trial was registered at the Chinese Clinical Trial Registry on 03/06/2023 ( www.chictr.org.cn ; ChiCTR ID: ChiCTR2300069071).


Assuntos
Terapia Cognitivo-Comportamental , Atenção Plena , Testes Psicológicos , Resiliência Psicológica , Esquizofrenia , Humanos , Esquizofrenia/terapia , Estigma Social , Pacientes Internados , Autoimagem
2.
J Chem Phys ; 160(4)2024 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-38294317

RESUMO

The knowledge of exact analytical functional forms for the pair correlation function g2(r) and its corresponding structure factor S(k) of disordered many-particle systems is limited. For fundamental and practical reasons, it is highly desirable to add to the existing database of analytical functional forms for such pair statistics. Here, we design a plethora of such pair functions in direct and Fourier spaces across the first three Euclidean space dimensions that are realizable by diverse many-particle systems with varying degrees of correlated disorder across length scales, spanning a wide spectrum of hyperuniform, typical nonhyperuniform, and antihyperuniform ones. This is accomplished by utilizing an efficient inverse algorithm that determines equilibrium states with up to pair interactions at positive temperatures that precisely match targeted forms for both g2(r) and S(k). Among other results, we realize an example with the strongest hyperuniform property among known positive-temperature equilibrium states, critical-point systems (implying unusual 1D systems with phase transitions) that are not in the Ising universality class, systems that attain self-similar pair statistics under Fourier transformation, and an experimentally feasible polymer model. We show that our pair functions enable one to achieve many-particle systems with a wide range of translational order and self-diffusion coefficients D, which are inversely related to one another. One can design other realizable pair statistics via linear combinations of our functions or by applying our inverse procedure to other desirable functional forms. Our approach facilitates the inverse design of materials with desirable physical and chemical properties by tuning their pair statistics.

3.
Molecules ; 29(7)2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38611918

RESUMO

Fever is a serious condition that can lead to various consequences ranging from prolonged illness to death. Tetrastigma hemsleyanum Diels et Gilg (T. hemsleyanum) has been used for centuries to treat fever, but the specific chemicals responsible for its antipyretic effects are not well understood. This study aimed to isolate and identify the chemicals with antipyretic bioactivity in T. hemsleyanum extracts and to provide an explanation for the use of T. hemsleyanum as a Chinese herbal medicine for fever treatment. Our results demonstrate that kaempferol 3-rutinoside (K3OR) could be successfully isolated and purified from the roots of T. hemsleyanum. Furthermore, K3OR exhibited a significant reduction in rectal temperature in a mouse model of fever. Notably, a 4 µM concentration of K3OR showed more effective antipyretic effects than ibuprofen and acetaminophen. To explore the underlying mechanism, we conducted an RNA sequencing analysis, which revealed that PXN may act as a key regulator in the fever process induced by lipopolysaccharide (LPS). In the mouse model of fever, K3OR significantly promoted the secretion of IL-6 and TNF-α during the early stage in the LPS-treated group. However, during the middle to late stages, K3OR facilitated the elimination of IL-6 and TNF-α in the LPS-treated group. Overall, our study successfully identified the chemicals responsible for the antipyretic bioactivity in T. hemsleyanum extracts, and it answered the question as to why T. hemsleyanum is used as a traditional Chinese herbal medicine for treating fever. These findings contribute to a better understanding of the therapeutic potential of T. hemsleyanum in managing fever, and they provide a basis for further research and development in this field.


Assuntos
Antocianinas , Antipiréticos , Medicamentos de Ervas Chinesas , Flavonas , Animais , Camundongos , Temperatura Corporal , Fator de Necrose Tumoral alfa/genética , Antipiréticos/farmacologia , Antipiréticos/uso terapêutico , Interleucina-6 , Quempferóis/farmacologia , Medicamentos de Ervas Chinesas/farmacologia , Lipopolissacarídeos , Febre/tratamento farmacológico , Flavonas/farmacologia , Flavonas/uso terapêutico , Modelos Animais de Doenças
4.
Biochem Biophys Res Commun ; 675: 155-161, 2023 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-37473530

RESUMO

Acute myeloid leukemia (AML) is a heterogeneous disease and about one third of AML patients carry nucleophosmin (NPM1) mutation. Because 95% mutations give NPM1 an additional nuclear export signaling (NES) and dislocate NPM1 in cytoplasm (NPMc+), relocating NPM1 in nucleus provide an innovative strategy for treating this type of AML. The nuclear export of NPM1 depends on the nuclear protein export receptor XPO1, which recognizes the NES sequence on NPM1. Homoharringtonine (HHT) is a first-line chemotherapy drug of AML, yet the exact mechanism of its anti-AML activity is elusive. In this study, we found that HHT can directly target XPO1 to its NES-binding cleft, bind to Cys528 of XPO1, and inhibits its nuclear transport function. In addition, HHT can block NPMc+ proteins nuclear export and thus make NPMc+ AML cells much more sensitive to HHT treatment. Furthermore, the sensitivity of NPMc+ AML cells to HHT is a universal phenomenon irrespective of the different genetic lesions of AML. Taken together, our findings suggest that XPO1 is a new target of HHT and provide a novel strategy for NPMc+ AML treatment.


Assuntos
Leucemia Mieloide Aguda , Humanos , Mepesuccinato de Omacetaxina , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/metabolismo , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Núcleo Celular/metabolismo , Citoplasma/metabolismo , Mutação
5.
Soft Matter ; 19(3): 550-564, 2023 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-36546870

RESUMO

The Zhang-Torquato conjecture [G. Zhang and S. Torquato, Phys. Rev. E, 2020, 101, 032124.] states that any realizable pair correlation function g2(r) or structure factor S(k) of a translationally invariant nonequilibrium system can be attained by an equilibrium ensemble involving only (up to) effective two-body interactions. To further test and study this conjecture, we consider two singular nonequilibrium models of recent interest that also have the exotic hyperuniformity property: a 2D "perfect glass" and a 3D critical absorbing-state model. We find that each nonequilibrium target can be achieved accurately by equilibrium states with effective one- and two-body potentials, lending further support to the conjecture. To characterize the structural degeneracy of such a nonequilibrium-equilibrium correspondence, we compute higher-order statistics for both models, as well as those for a hyperuniform 3D uniformly randomized lattice (URL), whose higher-order statistics can be very precisely ascertained. Interestingly, we find that the differences in the higher-order statistics between nonequilibrium and equilibrium systems with matching pair statistics, as measured by the "hole" probability distribution, provide measures of the degree to which a system is out of equilibrium. We show that all three systems studied possess the bounded-hole property and that holes near the maximum hole size in the URL are much rarer than those in the underlying simple cubic lattice. Remarkably, upon quenching, the effective potentials for all three systems possess local energy minima (i.e., inherent structures) with stronger forms of hyperuniformity compared to their target counterparts. Our methods are expected to facilitate the self-assembly of tunable hyperuniform soft-matter systems.

6.
J Fluoresc ; 33(6): 2503-2513, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37162634

RESUMO

Here, two novel naphthalimide derivatives SNI-Cz and SNI-DCz with AIE were designed and synthesized. The correctness of the two structures was characterized by NMR and HRMS. Their crystal structures, photophysical properties, electrochemical properties, thermal stabilities, fluorescence lifetime and yields have been characterized. Photoluminescence experiments revealed that SNI-DCz had superior properties due to the D-π-A-π-D structure and sliding away stacking of molecules. SNI-DCz exhibited weak fluorescence in pure DMF, with a significant AIE effect observed in the 40% water mixture and a sharp increase in fluorescence intensity was also observed. Cyclic voltammetry and thermogravimetric analysis indicated that SNI-DCz had good electron affinity and thermal stability. The excellent properties of SNI-DCz made it a promising emitter for optoelectronics.

7.
Int J Nurs Pract ; : e13204, 2023 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-37727093

RESUMO

AIMS: The present study aimed to explore the effects of a guided self-help mindfulness intervention on psychological resilience and job burnout among psychiatric nurses. BACKGROUND: Psychiatric nurses work in challenging and potentially high stress settings. Mindfulness interventions can improve psychological resilience and reduce job burnout of nurses. However, face-to-face delivery of mindfulness interventions may be inconvenient for individuals. Guided self-help interventions may be more accessible. METHODS: This randomized controlled trial was conducted from January to August 2022. One hundred and eighteen psychiatric nurses were randomized into the intervention and control groups. The individuals in the intervention group received an 8-week guided self-help mindfulness intervention, while the individuals in the control group received a psycho-educational brochure. The Five Facet Mindfulness Questionnaire, the Connor-Davidson Resilience Scale and the Maslach Burnout Inventory-Human Services Survey were used to evaluate the levels of mindfulness, psychological resilience and job burnout, respectively. RESULTS: After an 8-week intervention, compared with the control group, the levels of mindfulness and psychological resilience were higher, while the level of job burnout was lower in the intervention group. CONCLUSIONS: The guided self-help mindfulness intervention can improve psychological resilience and reduce job burnout among psychiatric nurses.

8.
Cancer Cell Int ; 22(1): 40, 2022 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-35081975

RESUMO

BACKGROUND: Rearrangements involving the fibroblast growth factor receptor 1 (FGFR1) gene result in 8p11 myeloproliferative syndrome (EMS), which is a rare and aggressive hematological malignancy that is often initially diagnosed as myelodysplastic syndrome (MDS). Clinical outcomes are typically poor due to relative resistance to tyrosine kinase inhibitors (TKIs) and rapid transformation to acute leukemia. Deciphering the transcriptomic signature of FGFR1 fusions may open new treatment strategies for FGFR1 rearrangement patients. METHODS: DNA sequencing (DNA-seq) was performed for 20 MDS patients and whole exome sequencing (WES) was performed for one HOOK3-FGFR1 fusion positive patient. RNA sequencing (RNA-seq) was performed for 20 MDS patients and 8 healthy donors. Fusion genes were detected using the STAR-Fusion tool. Fluorescence in situ hybridization (FISH), quantitative real-time PCR (qRT-PCR), and Sanger sequencing were used to confirm the HOOK3-FGFR1 fusion gene. The phosphorylation antibody array was performed to validate the activation of nuclear factor-kappaB (NF-kappaB) signaling. RESULTS: We identified frequently recurrent mutations of ASXL1 and U2AF1 in the MDS cohort, which is consistent with previous reports. We also identified a novel in-frame HOOK3-FGFR1 fusion gene in one MDS case with abnormal monoclonal B-cell lymphocytosis and ring chromosome 8. FISH analysis detected the FGFR1 break-apart signal in myeloid blasts only. qRT-PCR and Sanger sequencing confirmed the HOOK3-FGFR1 fusion transcript with breakpoints located at the 11th exon of HOOK3 and 10th exon of FGFR1, and Western blot detected the chimeric HOOK3-FGFR1 fusion protein that is presumed to retain the entire tyrosine kinase domain of FGFR1. The transcriptional feature of HOOK3-FGFR1 fusion was characterized by the significant enrichment of the NF-kappaB pathway by comparing the expression profiling of FGFR1 fusion positive MDS with 8 healthy donors and FGFR1 fusion negative MDS patients. Further validation by phosphorylation antibody array also showed NF-kappaB activation, as evidenced by increased phosphorylation of p65 (Ser 536) and of IKBalpha (Ser 32). CONCLUSIONS: The HOOK3-FGFR1 fusion gene may contribute to the pathogenesis of MDS and activate the NF-kappaB pathway. These findings highlight a potential novel approach for combination therapy for FGFR1 rearrangement patients.

9.
J Chem Phys ; 157(22): 224106, 2022 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-36546822

RESUMO

An outstanding problem in statistical mechanics is the determination of whether prescribed functional forms of the pair correlation function g2(r) [or equivalently, structure factor S(k)] at some number density ρ can be achieved by many-body systems in d-dimensional Euclidean space. The Zhang-Torquato conjecture states that any realizable set of pair statistics, whether from a nonequilibrium or equilibrium system, can be achieved by equilibrium systems involving up to two-body interactions. To further test this conjecture, we study the realizability problem of the nonequilibrium iso-g2 process, i.e., the determination of density-dependent effective potentials that yield equilibrium states in which g2 remains invariant for a positive range of densities. Using a precise inverse algorithm that determines effective potentials that match hypothesized functional forms of g2(r) for all r and S(k) for all k, we show that the unit-step function g2, which is the zero-density limit of the hard-sphere potential, is remarkably realizable up to the packing fraction ϕ = 0.49 for d = 1. For d = 2 and 3, it is realizable up to the maximum "terminal" packing fraction ϕc = 1/2d, at which the systems are hyperuniform, implying that the explicitly known necessary conditions for realizability are sufficient up through ϕc. For ϕ near but below ϕc, the large-r behaviors of the effective potentials are given exactly by the functional forms exp[ - κ(ϕ)r] for d = 1, r-1/2 exp[ - κ(ϕ)r] for d = 2, and r-1 exp[ - κ(ϕ)r] (Yukawa form) for d = 3, where κ-1(ϕ) is a screening length, and for ϕ = ϕc, the potentials at large r are given by the pure Coulomb forms in the respective dimensions as predicted by Torquato and Stillinger [Phys. Rev. E 68, 041113 (2003)]. We also find that the effective potential for the pair statistics of the 3D "ghost" random sequential addition at the maximum packing fraction ϕc = 1/8 is much shorter ranged than that for the 3D unit-step function g2 at ϕc; thus, it does not constrain the realizability of the unit-step function g2. Our inverse methodology yields effective potentials for realizable targets, and, as expected, it does not reach convergence for a target that is known to be non-realizable, despite the fact that it satisfies all known explicit necessary conditions. Our findings demonstrate that exploring the iso-g2 process via our inverse methodology is an effective and robust means to tackle the realizability problem and is expected to facilitate the design of novel nanoparticle systems with density-dependent effective potentials, including exotic hyperuniform states of matter.

10.
Psychol Health Med ; 27(7): 1602-1608, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-33779418

RESUMO

This study explored the relationship between social support and subjective well-being of the rural Chinese older adults and investigated whether self-worth could mediate this association. A total number of 356 older adults from rural areas of China were investigated using three scales. The results were as follows: there were significant correlations between social support, self-worth, and subjective well-being (where P < 0.01 in all of them). Bootstrapping mediation analyses indicated that self-worth partly mediated the association between social support and subjective well-being. Accordingly, social support and self-worth are important targets for improving the subjective well-being level of the rural older adults.


Assuntos
População Rural , Apoio Social , Idoso , China/epidemiologia , Estudos Transversais , Humanos
11.
J Gen Virol ; 102(3)2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33331812

RESUMO

Ovaliviridae is a family of enveloped viruses with a linear dsDNA genome. The virions are ellipsoidal, and contain a multi-layered spool-like capsid. The viral genome is presumably replicated through protein priming by a putative DNA polymerase encoded by the virus. Progeny virions are released through hexagonal openings resulting from the rupture of virus-associated pyramids formed on the surface of infected cells. The only known host is a hyperthermophilic archaeon of the genus Sulfolobus. This is a summary of the International Committee on Taxonomy of Viruses (ICTV) Report on the family Ovaliviridae, which is available at ictv.global/report/ovaliviridae.


Assuntos
Vírus de Archaea/classificação , Vírus de Archaea/fisiologia , Vírus de DNA/classificação , Vírus de DNA/fisiologia , Vírus de Archaea/genética , Vírus de Archaea/ultraestrutura , Capsídeo/ultraestrutura , Vírus de DNA/genética , Vírus de DNA/ultraestrutura , Genoma Viral , Sulfolobus/virologia , Vírion/genética , Vírion/fisiologia , Vírion/ultraestrutura , Replicação Viral
12.
J Virol ; 94(4)2020 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-31748395

RESUMO

Fuselloviruses are among the most widespread and best-characterized archaeal viruses. They exhibit remarkable diversity, as the list of members of this family is rapidly growing. However, it has yet to be shown how a fuselloviral genome may undergo variation at the levels of both single nucleotides and sequence stretches. Here, we report the isolation and characterization of four novel spindle-shaped viruses, named Sulfolobus spindle-shaped viruses 19 to 22 (SSV19-22), from a hot spring in the Philippines. SSV19 is a member of the genus Alphafusellovirus, whereas SSV20-22 belong to the genus Betafusellovirus The genomes of SSV20-SSV22 are identical except for the presence of two large variable regions, as well as numerous sites of single-nucleotide polymorphisms (SNPs) unevenly distributed throughout the genomes and enriched in certain regions, including the gene encoding the putative end filament protein VP4. We show that coinfection of the host with SSV20 and SSV22 led to the formation of an SSV21-like virus, presumably through homologous recombination. In addition, large numbers of SNPs were identified in DNA sequences retrieved by PCR amplification targeting the SSV20-22 vp4 gene from the original enrichment culture, indicating the enormous diversity of SSV20-22-like viruses in the environment. The high variability of VP4 is consistent with its potential role in host recognition and binding by the virus.IMPORTANCE How a virus survives in the arms race with its host is an intriguing question. In this study, we isolated and characterized four novel fuselloviruses, named Sulfolobus spindle-shaped viruses 19 to 22 (SSV19-22). Interestingly, SSV20-22 differ primarily in two genomic regions and are apparently convertible through homologous recombination during coinfection. Moreover, sites of single-nucleotide polymorphism (SNP) were identified throughout the genomes of SSV20-22 and, notably, enriched in certain regions, including the gene encoding the putative end filament protein VP4, which is believed to be involved in host recognition and binding by the virus.


Assuntos
Fuselloviridae/genética , Sulfolobus/genética , Sequência de Aminoácidos , Vírus de Archaea/genética , Evolução Biológica , Vírus de DNA/genética , DNA Viral/genética , Fuselloviridae/isolamento & purificação , Variação Genética/genética , Genoma Viral , Genômica/métodos , Fontes Termais/virologia , Filipinas , Sulfolobus/isolamento & purificação , Sulfolobus/virologia , Proteínas Virais/metabolismo
13.
J Chem Phys ; 153(12): 124106, 2020 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-33003740

RESUMO

We study the sensitivity and practicality of Henderson's theorem in classical statistical mechanics, which states that the pair potential v(r) that gives rise to a given pair correlation function g2(r) [or equivalently, the structure factor S(k)] in a classical many-body system at number density ρ and temperature T is unique up to an additive constant. While widely invoked in inverse-problem studies, the utility of the theorem has not been quantitatively scrutinized to any large degree. We show that Henderson's theorem has practical shortcomings for disordered and ordered phases for certain densities and temperatures. Using proposed sensitivity metrics, we identify illustrative cases in which distinctly different potential functions give very similar pair correlation functions and/or structure factors up to their corresponding correlation lengths. Our results reveal that due to a limited range and precision of pair information in either direct or reciprocal space, there is effective ambiguity of solutions to inverse problems that utilize pair information only, and more caution must be exercised when one claims the uniqueness of any resulting effective pair potential found in practice. We have also identified systems that possess virtually identical pair statistics but have distinctly different higher-order correlations. Such differences should be reflected in their individually distinct dynamics (e.g., glassy behaviors). Finally, we prove a more general version of Henderson's theorem that extends the uniqueness statement to include potentials that involve two- and higher-body interactions.

14.
Planta Med ; 86(12): 867-875, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32557519

RESUMO

Artemisia annua tea is a popular dosage form used to treat and prevent malaria in some developing countries. However, repeated drinking leads to an obviously decreased efficacy, which may be related to the induction of metabolizing enzymes by artemisinin. In the present study, the ability of different components in A. annua to activate the pregnane X receptor and constitutive androstane receptor was evaluated by the dual luciferase reporter gene system. The changes in mRNA and protein expression of CYP3A4 and CYP2B6 were determined by quantitative real-time PCR and Western blotting. Results showed that in the pregnane X receptor-mediated CYP3A4 reporter gene system, chrysosplenetin and arteannuin B exhibited a weak induction effect on pregnane X receptor wt, while arteannuin A had a strong induction effect on pregnane X receptor wt and pregnane X receptor 370 and a weak induction effect on pregnane X receptor 163. In the pregnane X receptor-mediated CYP2B6 reporter gene system, arteannuin A had a moderate induction effect on pregnane X receptor wt and pregnane X receptor 379, and a weak induction effect on pregnane X receptor 403, while arteannuin B had a weak induction effect on pregnane X receptor wt and pregnane X receptor 379. Arteannuin A had a strong induction effect on constitutive androstane receptor 3 in constitutive androstane receptor-mediated CYP3A4/2B6 reporter gene systems, while arteannuin B showed a weak induction effect on constitutive androstane receptor 3 in the constitutive androstane receptor-mediated CYP2B6 reporter gene system. The mRNA and protein expressions of CYP3A4 and CYP2B6 were increased when the pregnane X receptor or constitutive androstane receptor was activated. Various components present in A. annua differentially affect the activities of pregnane X receptor isoforms and the constitutive androstane receptor, which indicates the possibility of a drug-drug interaction. This partly explains the decline in efficacy after repeated drinking of A. annua tea.


Assuntos
Artemisia annua , Receptores de Esteroides/genética , Citocromo P-450 CYP2B6 , Citocromo P-450 CYP3A , Indução Enzimática , Hepatócitos , Extratos Vegetais , Receptores Citoplasmáticos e Nucleares
15.
J Virol ; 92(5)2018 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-29212941

RESUMO

A novel archaeal virus, denoted Sulfolobus ellipsoid virus 1 (SEV1), was isolated from an acidic hot spring in Costa Rica. The morphologically unique virion of SEV1 contains a protein capsid with 16 regularly spaced striations and an 11-nm-thick envelope. The capsid exhibits an unusual architecture in which the viral DNA, probably in the form of a nucleoprotein filament, wraps around the longitudinal axis of the virion in a plane to form a multilayered disk-like structure with a central hole, and 16 of these structures are stacked to generate a spool-like capsid. SEV1 harbors a linear double-stranded DNA genome of ∼23 kb, which encodes 38 predicted open reading frames (ORFs). Among the few ORFs with a putative function is a gene encoding a protein-primed DNA polymerase. Sixfold symmetrical virus-associated pyramids (VAPs) appear on the surface of the SEV1-infected cells, which are ruptured to allow the formation of a hexagonal opening and subsequent release of the progeny virus particles. Notably, the SEV1 virions acquire the lipid membrane in the cytoplasm of the host cell. The lipid composition of the viral envelope correlates with that of the cell membrane. These results suggest the use of a unique mechanism by SEV1 in membrane biogenesis.IMPORTANCE Investigation of archaeal viruses has greatly expanded our knowledge of the virosphere and its role in the evolution of life. Here we show that Sulfolobus ellipsoid virus 1 (SEV1), an archaeal virus isolated from a hot spring in Costa Rica, exhibits a novel viral shape and an unusual capsid architecture. The SEV1 DNA wraps multiple times in a plane around the longitudinal axis of the virion to form a disk-like structure, and 16 of these structures are stacked to generate a spool-like capsid. The virus acquires its envelope intracellularly and exits the host cell by creating a hexagonal hole on the host cell surface. These results shed significant light on the diversity of viral morphogenesis.


Assuntos
Proteínas do Capsídeo/química , Capsídeo/ultraestrutura , Genoma Arqueal , Genoma Viral , Sulfolobus/ultraestrutura , Sequência de Aminoácidos , Sequência de Bases , Proteínas do Capsídeo/metabolismo , Fontes Termais , Microscopia Eletrônica de Transmissão , Fases de Leitura Aberta , Homologia de Sequência de Aminoácidos , Sulfolobus/genética , Proteínas Virais/química , Proteínas Virais/genética , Proteínas Virais/metabolismo
16.
Cell Commun Signal ; 17(1): 54, 2019 05 27.
Artigo em Inglês | MEDLINE | ID: mdl-31133022

RESUMO

BACKGROUND: In previous research, we found that lamprey immune protein (LIP) possessed cytocidal activity against tumor cells, but the mechanism of the selective recognition and killing of tumor cells by LIP was not identified. METHODS: Superresolution microscopy, crystallographic structural analysis, glycan chip assay, SPR experiments, FACS assays, computational studies and mass spectrometric analysis firmly establish the mode of action of LIP, which involves dual selective recognition and efficient binding. RESULTS: We determined the overall crystallographic structure of LIP at a resolution of 2.25 Å. LIP exhibits an elongated structure with dimensions of 105 Å × 30 Å × 30 Å containing an N-terminal lectin module and a C-terminal aerolysin module. Moreover, the Phe209-Gly232 region is predicted to insert into the lipid bilayer to form a transmembrane ß-barrel, in which the hydrophobic residues face the lipid bilayer, and the polar residues constitute the hydrophilic lumen of the pore. We found that LIP is able to kill various human cancer cells with minimal effects on normal cells. Notably, by coupling biochemical and computational studies, we propose a hypothetical mechanism that involves dual selective recognition and efficient binding dependent on both N-linked glycans on GPI-anchored proteins (GPI-APs) and sphingomyelin (SM) in lipid rafts. Furthermore, specific binding of the lectin module with biantennary bisialylated nonfucosylated N-glycan or sialyl Lewis X-containing glycan structures on GPI-APs triggers substantial conformational changes in the aerolysin module, which interacts with SM, ultimately resulting in the formation of a membrane-bound oligomer in lipid rafts. CONCLUSIONS: LIP holds great potential for the application of a marine protein towards targeted cancer therapy and early diagnosis in humans.


Assuntos
Antineoplásicos/química , Citotoxinas/química , Proteínas de Peixes/química , Lampreias/metabolismo , Microdomínios da Membrana/efeitos dos fármacos , Animais , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Citotoxinas/farmacologia , Proteínas de Peixes/farmacologia , Proteínas Ligadas por GPI/metabolismo , Humanos , Lectinas/metabolismo , Microdomínios da Membrana/metabolismo , Simulação de Dinâmica Molecular , Ligação Proteica , Esfingomielinas/metabolismo
17.
Phys Chem Chem Phys ; 21(8): 4513-4522, 2019 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-30735214

RESUMO

The potential energy surface (PES) of a chemical system is an analytical function that outputs the potential energy of the system when a nuclear configuration is given as input. The PESs of small atmospheric clusters have theoretical as well as environmental significance. A common method used to generate analytical PESs is the Shepard interpolation, where the PES is a weighed sum of Taylor series expansions (nodal functions) at ab initio sample points. Based on this, in this study we present a new method based on the Shepard interpolation, where the nodal functions are composed of a symmetric Gaussian term and an asymmetric exponential term in each dimension. Corresponding sampling methods were also developed. We tested the method on several atmospheric bimolecular clusters and achieved root mean square errors (RMSE) below 0.13 kJ mol-1 in 150 samples for Ar-rigid H2O and Ne-rigid CO2, and below 0.39 kJ mol-1 in 1800 samples for rigid N2-rigid CO2.

18.
Pharmazie ; 73(11): 666-670, 2018 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-30396387

RESUMO

Hovenia dulcis Thunb. is a traditional hepatoprotective Chinese medicine, and in research, much effort has been focused on the protection against alcoholic liver injury. In this study, the protective effects of a fruit ethanol extract of Hovenia dulcis (FE) against APAP-induced acute hepatotoxicity in mice and the possibly involved molecular mechanisms were investigated. Hepatoprotective activity of FE is clearly indicated by histopathological and biochemical examination. Treatment with FE resulted in inhibition of CYP2E1 activity involved in the transformation of APAP in vivo. Expressions of the altered bile acid metabolism and transport-related genes and relative proteins of apoptosis were normalized by preconditioning with FE before APAP treatment. These results suggested FE to alleviate APAP-induced liver injury in a dose-dependent manner by inhibition of cytochrome P450 activity, hepatocyte apoptosis and regulation of bile acid homeostasis imbalance.


Assuntos
Acetaminofen/toxicidade , Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle , Extratos Vegetais/farmacologia , Rhamnaceae/química , Doença Aguda , Animais , Apoptose/efeitos dos fármacos , Ácidos e Sais Biliares/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Citocromo P-450 CYP2E1/efeitos dos fármacos , Citocromo P-450 CYP2E1/metabolismo , Relação Dose-Resposta a Droga , Medicamentos de Ervas Chinesas/administração & dosagem , Medicamentos de Ervas Chinesas/farmacologia , Frutas , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Extratos Vegetais/administração & dosagem , Ratos Wistar
19.
Biochem Biophys Res Commun ; 478(3): 1268-73, 2016 09 23.
Artigo em Inglês | MEDLINE | ID: mdl-27553277

RESUMO

The covalent modification of intrinsically nucleophilic cysteine in proteins is crucial for diverse biochemical events. Bioinformatics approaches may prove useful in the design and discovery of covalent molecules targeting the cysteine in proteins to tune their functions and activities. Herein, we describe the Cysteinome, the first online database that provides a rich resource for the display, search and analysis of structure, function and related annotation for proteins with targetable cysteine as well as their covalent modulators. To this end, Cysteinome compiles 462 proteins with targetable cysteine from 122 different species along with 1217 covalent modulators curated from existing literatures. Proteins are annotated with a detailed description of protein families, biological process and related diseases. In addition, covalent modulators are carefully annotated with chemical name, chemical structure, binding affinity, physicochemical properties, molecule type and related diseases etc. The Cysteinome database may serve as a useful platform for the identification of crucial proteins with targetable cysteine in certain cellular context. Furthermore, it may help biologists and chemists for the design and discovery of covalent chemical probes or inhibitors homing at functional cysteine of critical protein targets implicated in various physiological or disease process. The Cysteinome database is freely available to public at http://www.cysteinome.org/.


Assuntos
Cisteína/antagonistas & inibidores , Cisteína/metabolismo , Bases de Dados de Proteínas , Metaboloma , Cisteína/química , Internet
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