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1.
Front Vet Sci ; 11: 1427490, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39015103

RESUMO

Introduction: Globally, rodents and shrew populations constitute crucial elements of diverse environments and animal communities. It is imperative to study their population dynamics to mitigate any potential negative impact on humans, as they can be involved in the transmission of critical zoonotic agents, such as Blastocystis. Therefore, this study aimed to identify the prevalence and genetic composition of Blastocystis in wild rodents and shrews residing in the Zhejiang provinces of China. Methods: A total of 652 wild rodents and and shrews were captured from three different regions in Zhejiang Province from April 1st to October 31, 2023. The DNA was isolated by collecting fresh feces from the intestines of each rodent or and shrew. Rodent and shrew species were examined by vertebrate cytochrome b (cytb) analysis and PCR amplification. Blastocystis was also found in all fecal samples using PCR analysis and sequencing of the partial small subunit of ribosomal RNA (SSU rRNA) gene. Results: Among all the samples, 6.6% (43/652) showed a positive result for Blastocystis. In the results, 6 species of rodent and shrew were identified with Blastocystis, including Apodemus agrarius (n = 36) (2.8%), Niviventer confucianus (n = 75) (17.3%), Rattus losea (n = 18) (5.6%), R. norvegicus (n = 155) (2.6%), R. tanezumi (n = 86) (3.5%), and Suncus murinus (n = 282) (7.4%). The existence of 6 Blastocystis subtypes, ST4 (n = 33), ST1 (4), ST7 (n = 3), ST2 (n = 1), ST3 (n = 1), and ST5 (n = 1), were confirmed by sequence analysis. Discussion: Based on the molecular data obtained, the wild rodents and shrews under investigation were found to be concurrently infected with zoonotic subtypes of Blastocystis, including ST1 to ST5 and ST7. This suggests that these animals could potentially pose a zoonotic threat to humans and other animals susceptible to Blastocystis infection.

2.
Mol Pharm ; 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38920116

RESUMO

The continuous evolution of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has evaded the efficacy of previously developed antibodies and vaccines, thus remaining a significant global public health threat. Therefore, it is imperative to develop additional antibodies that are capable of neutralizing emerging variants. Nanobodies, as the smallest functional single-domain antibodies, exhibit enhanced stability and penetration ability, enabling them to recognize numerous concealed epitopes that are inaccessible to conventional antibodies. Herein, we constructed an immune library based on the immunization of alpaca with the S1 subunit of the SARS-CoV-2 spike protein, from which two nanobodies, Nb1 and Nb2, were selected using phage display technology for further characterization. Both nanobodies, with the binding residues residing within the receptor-binding domain (RBD) region of the spike, exhibited high affinity toward the S1 subunit. Moreover, they displayed cross-neutralizing activity against both wild-type SARS-CoV-2 and 10 ο variants, including BA.1, BA.2, BA.3, BA.5, BA.2.75, BF.7, BQ.1, EG.5.1, XBB.1.5, and JN.1. Molecular modeling and dynamics simulations predicted that both nanobodies interacted with the viral RBD through their complementarity determining region 1 (CDR1) and CDR2. These two nanobodies are novel tools for the development of therapeutic and diagnostic countermeasures targeting SARS-CoV-2 variants and potentially emerging coronaviruses.

3.
J Phys Chem Lett ; 15(25): 6467-6475, 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38869188

RESUMO

Photoexcitation induces intricate changes in both the real and imaginary components of the complex refractive index of thin film materials, which is essential for interpreting transient spectral features. Here, we employ a Kramers-Kronig-based analytical approach to elucidate light-induced changes in the complex refractive index from transient transmission spectra of thin films. Using gold-perovskite films as model systems, we conduct experimental measurements of transient transmission spectra for both individual gold and perovskite films, as well as for the bilayer heterostructure. Our analysis reveals significant changes in the refractive index and absorption for these systems. Notably, we observe negligible photocarrier transfer between the gold and perovskite layers based on transient spectroscopic analysis. These findings have implications for the design and optimization of bilayer heterostructures in optoelectronic applications. This work highlights the importance of spectroscopic techniques in studying the photophysical properties of heterostructure films.

4.
J Gen Physiol ; 156(7)2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38814250

RESUMO

The TMEM16A calcium-activated chloride channel is a promising therapeutic target for various diseases. Niclosamide, an anthelmintic medication, has been considered a TMEM16A inhibitor for treating asthma and chronic obstructive pulmonary disease (COPD) but was recently found to possess broad-spectrum off-target effects. Here, we show that, under physiological Ca2+ (200-500 nM) and voltages, niclosamide acutely potentiates TMEM16A. Our computational and functional characterizations pinpoint a putative niclosamide binding site on the extracellular side of TMEM16A. Mutations in this site attenuate the potentiation. Moreover, niclosamide potentiates endogenous TMEM16A in vascular smooth muscle cells, triggers intracellular calcium increase, and constricts the murine mesenteric artery. Our findings advise caution when considering clinical applications of niclosamide as a TMEM16A inhibitor. The identification of the putative niclosamide binding site provides insights into the mechanism of TMEM16A pharmacological modulation and provides insights into developing specific TMEM16A modulators to treat human diseases.


Assuntos
Anoctamina-1 , Niclosamida , Vasoconstrição , Niclosamida/farmacologia , Anoctamina-1/metabolismo , Anoctamina-1/genética , Animais , Camundongos , Humanos , Vasoconstrição/efeitos dos fármacos , Células HEK293 , Sítios de Ligação , Cálcio/metabolismo , Artérias Mesentéricas/efeitos dos fármacos , Artérias Mesentéricas/metabolismo , Músculo Liso Vascular/efeitos dos fármacos , Músculo Liso Vascular/metabolismo , Miócitos de Músculo Liso/efeitos dos fármacos , Miócitos de Músculo Liso/metabolismo , Masculino
5.
Artigo em Inglês | MEDLINE | ID: mdl-38598173

RESUMO

Motivated by the surging demand for low-temperature waste heat harvesting, materials with both prominent thermoelectric and good mechanical properties are preferred in practical applications. In this present work, the composite exploration of Te-doped Mg3.2Bi1.5Sb0.5-x vol % nanosized SiC (x = 0, 0.05, 0.1, 0.2, and 0.5) was carried out, where nanosized SiC is physically dispersed in the matrix in the form of a second phase. SiC second phase compositing further optimized the matrix carrier concentration, resulting in a higher power factor in the service temperature range (the highest value from 28.9 to 31.7 µW cm-1 K-2), and the (ZT)ave from 0.91 to 0.96 compared with the matrix sample. In addition, the SiC second phase effectively enhanced the mechanical properties of composite materials, including flexural strength, microhardness, and modulus. Because of the simultaneous optimization of thermoelectric and mechanical properties, the overall performance of Te-doped Mg3.2Bi1.5Sb0.5-0.05 vol % SiC composite is leveraged to meet special requirements of power generation. It is expected that the addition of SiC should be broadly applicable to address the physical performance in other thermoelectric systems.

6.
Microorganisms ; 12(4)2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38674755

RESUMO

Globally, Enterocytozoon bieneusi has been detected in humans and various animal hosts. Wild rats and shrews have the potential to act as carriers of E. bieneusi, facilitating the parasite's transmission to humans and domestic animals. We aimed to investigate the prevalence of E. bieneusi in 652 wild rats and shrews from Zhejiang Province, China, by amplifying the internal transcribed spacer (ITS) region of rDNA through polymerase chain reaction (PCR). To determine animal species, we amplified the Cytochrome b (Cyt-b) gene in their fecal DNA using PCR. Furthermore, we determined the genotype of E. bieneusi by amplifying the ITS region of rDNA through PCR. Genetic traits and zoonotic potential were evaluated using similarity and phylogenetic analyses. Suncus murinus (n = 282) and five rat species, Rattus losea (n = 18), Apodemus agrarius (n = 36), Rattus tanezumi (n = 86), Rattus norvegicus (n = 155), and Niviventer niviventer (n = 75), were identified. The average infection rate of E. bieneusi was 14.1% (92/652) with 18.1% (51/282) in S. murinus and 11.1% (41/370) in rats (27.8% in R. losea, 22.2% in A. agrarius, 10.5% in R. tanezumi, 8.4% in R. norvegicus, and 8.0% in N. niviventer). Thirty-three genotypes were identified, including 16 known genotypes. The most commonly known genotypes were HNR-VI (n = 47) and Peru11 (n = 6). Type IV, KIN-1, SHW7, and HNPL-II were each found in two samples, while Macaque4, CH5, K, Henan-III, Henan-V, HNP-II, HNPL-I, HNPL-III, HNHZ-II, and HNHZ-III were each found in one sample. Additionally, 17 novel genotypes were discovered: WZR-VIII (n = 5), WZR-I to WZR-VII, WZR-IX to WZR-XII, and WZSH-I to WZSH-V (n = 1 each). Those 33 genotypes were divided into three groups: Group 1 (n = 25), Group 2 (n = 3), and Group 13 (n = 5). The initial report underscores the extensive occurrence and notable genetic diversity of E. bieneusi in wild rats and shrews from Zhejiang province, China. These results suggest that these animals play a pivotal role in the transmission of E. bieneusi. Furthermore, animals carrying the zoonotic genotypes of E. bieneusi pose a serious threat to residents.

7.
Virol Sin ; 39(3): 414-421, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38677713

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative agent of COVID-19, encodes several accessory proteins that have been shown to play crucial roles in regulating the innate immune response. However, their expressions in infected cells and immunogenicity in infected humans and mice are still not fully understood. This study utilized various techniques such as luciferase immunoprecipitation system (LIPS), immunofluorescence â€‹assay (IFA), and western â€‹blot (WB) to detect accessory protein-specific antibodies in sera of COVID-19 patients. Specific antibodies to proteins 3a, 3b, 7b, 8 and 9c can be detected by LIPS, but only protein 3a antibody was detected by IFA or WB. Antibodies against proteins 3a and 7b were only detected in ICU patients, which may serve as a marker for predicting disease progression. Further, we investigated the expression of accessory proteins in SARS-CoV-2-infected cells and identified the expressions of proteins 3a, 6, 7a, 8, and 9b. We also analyzed their ability to induce antibodies in immunized mice and found that only proteins 3a, 6, 7a, 8, 9b and 9c were able to induce measurable antibody productions, but these antibodies lacked neutralizing activities and did not protect mice from SARS-CoV-2 infection. Our findings validate the expression of SARS-CoV-2 accessory proteins and elucidate their humoral immune response, providing a basis for protein detection assays and their role in pathogenesis.


Assuntos
Anticorpos Antivirais , COVID-19 , Modelos Animais de Doenças , Imunidade Humoral , SARS-CoV-2 , Animais , Humanos , SARS-CoV-2/imunologia , COVID-19/imunologia , COVID-19/virologia , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Camundongos , Feminino , Camundongos Endogâmicos BALB C , Masculino , Pessoa de Meia-Idade , Anticorpos Neutralizantes/imunologia , Anticorpos Neutralizantes/sangue , Adulto , Idoso
8.
Tumori ; : 3008916231221636, 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-38183180

RESUMO

The microenvironment of diffuse large B-cell lymphoma (DLBCL) is composed of various components, including immune cells and immune checkpoints, some of which have been correlated with the prognosis of DLBCL, but their results remain controversial. Therefore, we conducted a systematic review and meta-analysis to investigate the association between the microenvironment and prognosis in DLBCL. We searched PubMed, Web of Science, and EMBASE for relevant articles between 2001 and 2022. Twenty-five studies involving 4495 patients with DLBCL were included in the analysis. This meta-analysis confirmed that high densities of Foxp3+Tregs and PD-1+T cells are good indicators for overall survival (OS) in DLBCL, while high densities of programmed cell death protein ligand1(PD-L1)-positive expression cells and T-cell immunoglobulin-and mucin domain-3-containing molecule 3 (TIM-3)-positive expression tumor-infiltrating cells (TILs) play a contrary role in OS. Additionally, higher numbers of T-cell intracytoplasmic antigen-1(TIA-1)-positive expression T cells imply better OS and progression-free survival (PFS), while high numbers of lymphocyte activation gene(LAG)-positive expression TILs predict bad OS and PFS. Various non-tumoral cells in the microenvironment play important roles in the prognosis of DLBCL.

9.
Adv Sci (Weinh) ; 11(9): e2303366, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38105421

RESUMO

To combat SARS-CoV-2 variants and MERS-CoV, as well as the potential re-emergence of SARS-CoV and spillovers of sarbecoviruses, which pose a significant threat to global public health, vaccines that can confer broad-spectrum protection against betacoronaviruses (ß-CoVs) are urgently needed. A mosaic ferritin nanoparticle vaccine is developed that co-displays the spike receptor-binding domains of SARS-CoV, MERS-CoV, and SARS-CoV-2 Wild-type (WT) strain and evaluated its immunogenicity and protective efficacy in mice and nonhuman primates. A low dose of 10 µg administered at a 21-day interval induced a Th1-biased immune response in mice and elicited robust cross-reactive neutralizing antibody responses against a variety of ß-CoVs, including a series of SARS-CoV-2 variants. It is also able to effectively protect against challenges of SARS-CoV, MERS-CoV, and SARS-CoV-2 variants in not only young mice but also the more vulnerable mice through induction of long-lived immunity. Together, these results suggest that this mosaic 3-RBD nanoparticle has the potential to be developed as a pan-ß-CoV vaccine.


Assuntos
Infecções por Coronavirus , Coronavírus da Síndrome Respiratória do Oriente Médio , Nanopartículas , Vacinas Virais , Humanos , Animais , Camundongos , Anticorpos Neutralizantes , Anticorpos Antivirais , Infecções por Coronavirus/prevenção & controle , SARS-CoV-2 , Coronavírus da Síndrome Respiratória do Oriente Médio/química , Modelos Animais
10.
Sci Total Environ ; 904: 166744, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37659528

RESUMO

BACKGROUND: Little is known about the associations of exposure to fine particulate matter (PM2.5) and its constituents with ovarian reserve, and the potential susceptible window of exposure remains unclear. METHODS: We performed a retrospective cohort study of 5189 women who attended a fertility center in Hubei, China, during 2019-2022, and estimated concentrations of PM2.5 and its major constituents during the development of follicles (4th-6th month [W1], 0-4th month [W2], 0-6th month [W3]) and 1-year before measurement (W4) based on Tracking Air Pollution in China database. We used multivariable linear regression and logistic regression models to examine the associations of PM2.5 and its constituent exposures with anti-Müllerian hormone (AMH), the preferred indicator of ovarian reserve. RESULTS: We observed significantly decreased AMH levels associated with increasing PM2.5 concentrations, with the percent changes (95 % confidence intervals [CIs]) of 1.99 % (0.24 %-3.71 %) during W1 and 3.99 % (0.74 %-7.15 %) during W4 for per 10 µg/m3 increases in PM2.5.When PM2.5 exposure levels were equal to 50th percentile (32.6-42.3 µg/m3) or more, monotonically decreased AMH levels and increased risks of low AMH were seen with increasing PM2.5 concentrations during W1 and W4 (P < 0.05). Black carbon (BC), ammonium (NH4+), nitrate (NO3-), and organic matter (OM) during W1, and NH4+, NO3-, as well as sulfate (SO42-) during W4 were significantly associated with decreased AMH. Moreover, PM2.5 and SO42- exposures during W4 were positively associated with low AMH. Additionally, the associations were stronger among women aged <35 years, lived in urban regions, or measured AMH in cold-season (P for interaction <0.05). CONCLUSION: PM2.5 and specific chemical components (particularly NH4+, NO3-, and SO42-) exposure during the secondary to antral follicle stage and 1-year before measurement were associated with diminished ovarian reserve (DOR), indicating the adverse impact of PM2.5 and its constituent exposures on female reproductive potential.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Reserva Ovariana , Feminino , Humanos , Material Particulado/análise , Estudos Retrospectivos , Poluição do Ar/análise , Fertilidade , Hormônio Antimülleriano , China , Poluentes Atmosféricos/análise , Exposição Ambiental
11.
Clin Lab ; 69(8)2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37560870

RESUMO

BACKGROUND: This study aimed to investigate the value of miR-671-5p in multiple myeloma (MM) in diagnostics and prognosis and developed a potential biomarker to improve the prognosis of MM. METHODS: Plasma cells were isolated from bone marrow samples of 80 MM patients, in which miR-671-5p levels were determined. The correlation between miR-671-5p expression with serum creatinine, ß-2-microglobulin, lactate dehydrogenase, bone lesions, International Staging System staging, chromosomal abnormalities, and albumin was analyzed. The association between miR-671-5p expression with progression-free survival and overall survival in MM patients was determined. RESULTS: miR-671-5p expression was reduced and predicted an increased risk of MM. miR-671-5p expression was negatively correlated with serum creatinine, ß-2-microglobulin, lactate dehydrogenase, bone lesions, International Staging System staging, and chromosomal abnormalities, and positively correlated with albumin. miR-671-5p expression was augmented in complete response patients and overall response rate patients, and differentiated CR and ORR patients from Non-CR and Non-ORR patients. Furthermore, miR-671-5p low expression was associated with unfavorable progression-free survival and overall survival in MM patients. CONCLUSIONS: In a word, miR-671-5p is associated with worsening clinical properties, increased ISS staging, unfavorable chromosomal abnormalities, and poor prognosis in MM patients.


Assuntos
MicroRNAs , Mieloma Múltiplo , Humanos , MicroRNAs/genética , Mieloma Múltiplo/diagnóstico , Mieloma Múltiplo/genética , Creatinina , Prognóstico , Albuminas , Aberrações Cromossômicas , Lactato Desidrogenases
12.
bioRxiv ; 2023 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-37577682

RESUMO

The TMEM16A calcium-activated chloride channel is a promising therapeutic target for various diseases. Niclosamide, an anthelmintic medication, has been considered as a TMEM16A inhibitor for treating asthma and chronic obstructive pulmonary disease, but was recently found to possess broad-spectrum off-target effects. Here we show that, under physiological conditions, niclosamide acutely potentiates TMEM16A without having any inhibitory effect. Our computational and functional characterizations pinpoint a putative niclosamide binding site on the extracellular side of TMEM16A. Mutations in this site attenuate the potentiation. Moreover, niclosamide potentiates endogenous TMEM16A in vascular smooth muscle cells, triggers intracellular calcium increase, and constricts the murine mesenteric artery. Our findings advise caution when considering niclosamide as a TMEM16A inhibitor to treat diseases such as asthma, COPD, and hypertension. The identification of the putative niclosamide binding site provides insights into the mechanism of TMEM16A pharmacological modulation, shining light on developing specific TMEM16A modulators to treat human diseases.

13.
Front Public Health ; 11: 1159348, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37457253

RESUMO

Background: Noise energy has been well-established to increase the risk of occupational noise-induced hearing loss (NIHL). However, the role of noise temporal structure (expressed by kurtosis) or its combination with energy metrics (e.g., kurtosis-adjusted cumulative noise exposure, adj-CNE) in occupational NIHL was still unclear. Methods: A cross-sectional survey of 867 Chinese workers, including 678 metal manufacturing workers and 189 workers exposed to Gaussian noise, was conducted. Noise energy metrics, including LAeq,8h and CNE, kurtosis (ß), and adj-CNE were used to quantify noise exposure levels. Noise-induced permanent threshold shift at frequencies 3, 4, and 6 kHz (NIPTS346) and the prevalence of high-frequency NIHL (HFNIHL%) were calculated for each participant. The dose-response relationship between kurtosis or adj-CNE and occupational NIHL was observed. Results: Among 867 workers, different types of work had specific and independent noise energy and kurtosis values (p > 0.05). HFNIHL% increased with an increase in exposure duration (ED), LAeq,8h, CNE, or kurtosis (p < 0.01), and there were strong linear relationships between HFNIHL% and ED (coefficient of determination [R2] = 0.963), CNE (R2 = 0.976), or kurtosis (R2 = 0.938, when CNE < 100 dB(A)∙year). The "V" shape notching extent in NIPTS became deeper with increasing kurtosis when CNE < 100 dB(A)∙year and reached the notching bottom at the frequency of 4 or 6 kHz. The workers exposed to complex noise (ß ≥ 10) had a higher risk of NIHL than those exposed to Gaussian noise (ß < 10) at the frequencies of 3, 4, 6, and 8 kHz (OR > 2, p < 0.01). Moreover, HFNIHL% increased with adj-CNE (p < 0.001). There were strong linear relationships between NIHL and adj-CNE or CNE when ß ≥ 10 (R2adj-CNE > R2CNE). After CNE was adjusted by kurtosis, average differences in NIPTS346 or HFNIHL% between the complex and Gaussian noise group were significantly reduced (p < 0.05). Conclusion: Kurtosis was a key factor influencing occupational NIHL among metal manufacturing workers, and its combination with energy metrics could assess the risk of NIHL more effectively than CNE alone.


Assuntos
Perda Auditiva Provocada por Ruído , Ruído Ocupacional , Exposição Ocupacional , Humanos , Perda Auditiva Provocada por Ruído/epidemiologia , Perda Auditiva Provocada por Ruído/etiologia , Exposição Ocupacional/efeitos adversos , Estudos Transversais , Inquéritos e Questionários , Ruído Ocupacional/efeitos adversos
14.
Ann Diagn Pathol ; 66: 152165, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37348414

RESUMO

PURPOSE: Diffuse large B-cell lymphoma (DLBCL) is a heterogeneous group of non-Hodgkin lymphoma, characterized by a variety of clinicopathological, histomorphological, immunophenotypic, and molecular genetic features. The subtype of DLBCL known as double-expressor lymphoma (DEL) is associated with an adverse prognosis when treated with R-CHOP. Our study aimed to investigate the clinicopathologic features of DEL and the prognostic roles of Myc rearrangement and C-Myc expression in DEL patients. PATIENTS AND METHODS: We conducted a retrospective study of 145 patients who were identified through fluorescence in situ hybridization (FISH) and immunohistochemistry (IHC) testing. RESULTS: We found that DEL patients were more likely to have a non-germinal center B-cell (GCB) subtype, stage III/IV disease, and a high International Prognostic Index (IPI) score. Our survival analysis indicated that Myc rearrangement and C-Myc expression were associated with poor prognosis. Although DEL patients with Myc rearrangement exhibited trends towards worse survival compared with patients without Myc rearrangement, the differences were not statistically significant (P = 0.4008). The median overall survival (OS) of DEL patients with ≥70 % C-Myc expression (DEL-C-Mychigh) was 5 months. In the DEL-C-Mychigh group, the non-GCB subtype showed nonsignificant trends towards poorer survival compared with the GCB subtype (P = 0.1042). CONCLUSION: In conclusion, our study shows that a cut-off of ≥70 % for C-Myc expression in DEL patients can improve risk stratification, and suggests that more intensive treatment regimens may be necessary to improve survival in this high-risk population.


Assuntos
Linfoma Difuso de Grandes Células B , Proteínas Proto-Oncogênicas c-myc , Humanos , Estudos Retrospectivos , Hibridização in Situ Fluorescente , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo , Prognóstico , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Linfoma Difuso de Grandes Células B/diagnóstico , Linfoma Difuso de Grandes Células B/genética , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico
15.
Org Lett ; 25(20): 3607-3610, 2023 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-37166363

RESUMO

An enantioselective metal-free hydrogenation of hydrazones has been realized successfully using chiral boranes as catalysts, producing a range of optically active hydrazines in 87-99% yields with 75-93% ee's. The bulky 2,2,6,6-tetramethylpiperidinyl moiety was found to be essential for achieving the high enantioselectivities.

16.
Photoacoustics ; 31: 100494, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37131996

RESUMO

Membrane viscosity is an important property of cell biology, which determines cellular function, development and disease progression. Various experimental and computational methods have been developed to investigate the mechanics of cells. However, there have been no experimental measurements of the membrane viscosity at high-frequencies in live cells. High frequency measurements are important because they can probe viscoelastic effects. Here, we investigate the membrane viscosity at gigahertz-frequencies through the damping of the acoustic vibrations of gold nanoplates. The experiments are modeled using a continuum mechanics theory which reveals that the membranes display viscoelasticity, with an estimated relaxation time of ca. 5.7 + 2.4 / - 2.7 ps. We further demonstrate that membrane viscoelasticity can be used to differentiate a cancerous cell line (the human glioblastoma cells LN-18) from a normal cell line (the mouse brain microvascular endothelial cells bEnd.3). The viscosity of cancerous cells LN-18 is lower than that of healthy cells bEnd.3 by a factor of three. The results indicate promising applications of characterizing membrane viscoelasticity at gigahertz-frequency in cell diagnosis.

17.
Nat Cancer ; 4(3): 382-400, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36894639

RESUMO

Immunotherapies targeting the PD-1/PD-L1 axis have become first-line treatments in multiple cancers. However, only a limited subset of individuals achieves durable benefits because of the elusive mechanisms regulating PD-1/PD-L1. Here, we report that in cells exposed to interferon-γ (IFNγ), KAT8 undergoes phase separation with induced IRF1 and forms biomolecular condensates to upregulate PD-L1. Multivalency from both the specific and promiscuous interactions between IRF1 and KAT8 is required for condensate formation. KAT8-IRF1 condensation promotes IRF1 K78 acetylation and binding to the CD247 (PD-L1) promoter and further enriches the transcription apparatus to promote transcription of PD-L1 mRNA. Based on the mechanism of KAT8-IRF1 condensate formation, we identified the 2142-R8 blocking peptide, which disrupts KAT8-IRF1 condensate formation and consequently inhibits PD-L1 expression and enhances antitumor immunity in vitro and in vivo. Our findings reveal a key role of KAT8-IRF1 condensates in PD-L1 regulation and provide a competitive peptide to enhance antitumor immune responses.


Assuntos
Antígeno B7-H1 , Receptor de Morte Celular Programada 1 , Humanos , Linhagem Celular Tumoral , Antígeno B7-H1/genética , Receptor de Morte Celular Programada 1/metabolismo , Interferon gama/genética , Interferon gama/farmacologia , Imunoterapia , Histona Acetiltransferases/metabolismo , Fator Regulador 1 de Interferon/genética , Fator Regulador 1 de Interferon/metabolismo
18.
Proc Natl Acad Sci U S A ; 120(12): e2218825120, 2023 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-36917666

RESUMO

Interferons (IFNs) and the products of interferon-stimulated genes (ISGs) play crucial roles in host defense against virus infections. Although many ISGs have been characterized with respect to their antiviral activity, their target specificities and mechanisms of action remain largely unknown. Kaposi's sarcoma-associated herpesvirus (KSHV) is a gammaherpesvirus that is linked to several human malignancies. Here, we used the genetically and biologically related virus, murine gammaherpesvirus 68 (MHV-68) and screened for ISGs with anti-gammaherpesvirus activities. We found that overexpression of RNF213 dramatically inhibited MHV-68 infection, whereas knockdown of endogenous RNF213 significantly promoted MHV-68 proliferation. Importantly, RNF213 also inhibited KSHV de novo infection, and depletion of RNF213 in the latently KSHV-infected iSLK-219 cell line significantly enhanced lytic reactivation. Mechanistically, we demonstrated that RNF213 targeted the Replication and Transcription Activator (RTA) of both KSHV and MHV-68, and promoted the degradation of RTA protein through the proteasome-dependent pathway. RNF213 directly interacted with RTA and functioned as an E3 ligase to ubiquitinate RTA via K48 linkage. Taken together, we conclude that RNF213 serves as an E3 ligase and inhibits the de novo infection and lytic reactivation of gammaherpesviruses by degrading RTA through the ubiquitin-proteasome pathway.


Assuntos
Gammaherpesvirinae , Infecções por Herpesviridae , Herpesvirus Humano 8 , Proteínas Imediatamente Precoces , Humanos , Adenosina Trifosfatases/metabolismo , Gammaherpesvirinae/genética , Regulação Viral da Expressão Gênica , Infecções por Herpesviridae/genética , Herpesvirus Humano 8/metabolismo , Proteínas Imediatamente Precoces/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo , Transativadores/metabolismo , Fatores de Transcrição/metabolismo , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo , Latência Viral/genética , Replicação Viral
19.
Sci Total Environ ; 854: 158606, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36089043

RESUMO

Global concern over microplastics (MPs) is increasing because of the potential threat these substances pose to ecosystem and human health. Disposable cups, frequently used as containers of beverages, are typically made of plastic or plastic-coated paper. The release of MPs from disposable cups during use may provide a direct exposure pathway for humans. In this study, the MP release capacities of 90 batches of commercial disposable cups, including polyethylene (PE)-coated paper cups, polypropylene (PP) cups, and polystyrene (PS) cups, were investigated under daily use conditions, and the properties of released MP particles are characterized with Raman spectroscopy, scanning electron microscopy (SEM), and atomic force microscopy (AFM). The MPs release into containing beverages is detected for each of the tested cups in this study. The released MPs particles are in irregular shapes and dominantly smaller than 20 µm. The quantities of released MPs are in the range of 675-5984, 781-4951, and 838-5215 particles/L for PE-coated paper cups, PP cups and PS cups, respectively, when containing pure water at 95 °C for 20 min. No significant difference in the quantity of MP released is observed among the three types of the cups in the experimental conditions. High temperature is found to promote the release of MPs from disposable cups. The MP release is notable when the cups are used for a second time, although at a slightly lower level than the first use. Acidic carbonated beverages obviously enhance MP release from PE-coated cups over that of ultrapure water.


Assuntos
Microplásticos , Poluentes Químicos da Água , Humanos , Plásticos/química , Ecossistema , Polipropilenos/análise , Poliestirenos , Água , Polietileno , Poluentes Químicos da Água/análise , Monitoramento Ambiental
20.
Nat Hum Behav ; 7(2): 200-210, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36482078

RESUMO

Cooking is practiced worldwide and is associated with multiple social, economic and environmental factors; thus, understanding cooking-related health effects would have broad public health implications. Here, we show that after an average 9.9 years of follow-up for 510,106 Chinese adults, always cooking with clean fuels was associated with lower risks of all-cause (0.90 [95% confidence interval 0.87-0.93]; P = 1.39 × 10-9), cardiovascular (0.83 [0.78-0.87]; P = 6.83 × 10-11) and respiratory (0.88 [0.79-0.99]; P = 0.026) mortality compared with non-cooking, of which 50.1% (14.5-85.6%) to 66.0% (38.5-85.8%) could be attributed to increased household physical activity. The mortality risks decreased with extended duration of cooking with clean fuels in dose-response manners, with the lowest hazard ratios of 0.74 (0.68-0.80; P = 1.20 × 10-13) for all-cause and 0.62 (0.55-0.71; P = 3.15 × 10-12) for cardiovascular mortality among never-smokers reported over 25 years of cooking. Our findings suggest lower future mortality risks may be gained only when cooking with clean fuels.


Assuntos
Poluição do Ar em Ambientes Fechados , Características da Família , Adulto , Humanos , Estudos Prospectivos , Culinária
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