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1.
Molecules ; 29(12)2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38930983

RESUMO

The Lichen moth, Lyclene dharma dharma (Arctiidae, Lithosiinae), plays a significant role in forest ecosystem dynamics. A concise and novel method to synthesize the active sex pheromone components, (S)-14-methyloctadecan-2-one ((S)-1), (S)-6-methyloctadecan-2-one ((S)-2), and their enantiomers has been developed. Key steps in the synthesis include the use of Evans' chiral auxiliaries, Grignard cross-coupling reactions, hydroboration-oxidation, and Wacker oxidation. The synthesized sex pheromone components hold potential value for studies on communication mechanisms, species identification, and ecological management.


Assuntos
Mariposas , Atrativos Sexuais , Atrativos Sexuais/química , Atrativos Sexuais/síntese química , Animais , Estereoisomerismo , Feminino , Estrutura Molecular
2.
Opt Express ; 31(16): 26807-26814, 2023 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-37710531

RESUMO

We report a pulse Fe: ZnSe laser pumped by an optical chopper Q-switched Er: YAG laser. By analyzed the spatial and temporal match of the gain and chopper, the maximum energy of the optical chopper Q-switched Er: YAG laser is 31mJ with the pulse width of 165 ns. By employing this Er: YAG laser as pump laser of Fe: ZnSe crystal, the maximum output energy of Fe: ZnSe laser is 10mJ with the pulse width of 80 ns at room temperature, that is the maximum energy of Fe: ZnSe laser at this Q-switched system to the best of our knowledge. We also study the directly Q-switched Fe: ZnSe laser, and the 2.7mJ mid-infrared laser with the pulse width of 200 ns is obtained at 80 K.

3.
J Transl Med ; 19(1): 51, 2021 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-33536036

RESUMO

BACKGROUND: Currently, there is no reliable blood-based marker to track tumor recurrence in endometrial cancer (EC) patients. Liquid biopsies, specifically, circulating tumor DNA (ctDNA) analysis emerged as a way to monitor tumor metastasis. The objective of this study was to examine the feasibility of ctDNA in recurrence surveillance and prognostic evaluation of high-risk EC. METHODS: Tumor tissues from nine high-risk EC patients were collected during primary surgery and tumor DNA was subjected to next generation sequencing to obtain the initial mutation spectrum using a 78 cancer-associated gene panel. Baseline and serial post-operative plasma samples were collected and droplet digital PCR (ddPCR) assays for patient-specific mutations were developed to track the mutations in the ctDNA in serial plasma samples. Log-rank test was used to assess the association between detection of ctDNA before or after surgery and disease-free survival. RESULTS: Somatic mutations were identified in all of the cases. The most frequent mutated genes were PTEN, FAT4, ARID1A, TP53, ZFHX3, ATM, and FBXW7. For each patient, personalized ddPCR assays were designed for one-to-three high-frequent mutations. DdPCR analysis and tumor panel sequencing had a high level of agreement in the assessment of the mutant allele fractions in baseline tumor tissue DNA. CtDNA was detected in 67% (6 of 9) of baseline plasma samples, which was not predictive of disease-free survival (DFS). CtDNA was detected in serial post-operative plasma samples (ctDNA tracking) of 44% (4 of 9) of the patients, which predicted tumor relapse. The DFS was a median of 9 months (ctDNA detected) versus median DFS undefined (ctDNA not detected), with a hazard ratio of 17.43 (95% CI, 1.616-188.3). The sensitivity of post-operative ctDNA detection in estimating tumor relapse was 100% and specificity was 83.3%, which was superior to CA125 or HE4. CONCLUSIONS: Personalized ctDNA detection was effective and stable for high-risk EC. CtDNA tracking in post-operative plasma is valuable for predicting tumor recurrence.


Assuntos
DNA Tumoral Circulante , Neoplasias do Endométrio , Biomarcadores Tumorais/genética , DNA Tumoral Circulante/genética , Neoplasias do Endométrio/diagnóstico , Neoplasias do Endométrio/genética , Feminino , Humanos , Mutação/genética , Recidiva Local de Neoplasia/genética , Prognóstico
4.
NPJ Vaccines ; 9(1): 44, 2024 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-38402256

RESUMO

The human papillomavirus minor capsid protein L2 is being extensively explored in pre-clinical studies as an attractive vaccine antigen capable of inducing broad-spectrum prophylactic antibody responses. Recently, we have developed two HPV vaccine antigens - PANHPVAX and CUT-PANHPVAX- both based on heptameric nanoparticle antigens displaying polytopes of the L2 major cross-neutralizing epitopes of eight mucosal and twelve cutaneous HPV types, respectively. Prompted by the variable neutralizing antibody responses against some of the HPV types targeted by the antigens observed in previous studies, here we investigated the influence on immunogenicity of six distinct glycine-proline spacers inserted upstream to a specific L2 epitope. We show that spacer variants differentially influence antigen immunogenicity in a mouse model, with the antigen constructs M8merV6 and C12merV6 displaying a superior ability in the induction of neutralizing antibodies as determined by pseudovirus-based neutralization assays (PBNAs). L2-peptide enzyme-linked immunosorbent assay (ELISA) assessments determined the total anti-L2 antibody level for each antigen variant, showing for the majority of sera a correlation with their repective neutralizing antibody level. Surface Plasmon Resonance revealed that L2 epitope-specific, neutralizing monoclonal antibodies (mAbs) display distinct avidities to different antigen spacer variants. Furthermore, mAb affinity toward individual spacer variants was well correlated with their neutralizing antibody induction capacity, indicating that the mAb affinity assay predicts L2-based antigen immunogenicity. These observations provide insights on the development and optimization of L2-based HPV vaccines.

5.
NPJ Vaccines ; 9(1): 119, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38926425

RESUMO

Persistent infection with high-risk human papillomavirus (HPV) is widely recognized as the primary cause of cervical and other malignant cancers. There are six licensed prophylactic vaccines available against HPV, but none of them shows any significant therapeutic effect on pre-existing infections or lesions. Thus, a prophylactic vaccine also endowed with therapeutic activity would afford protection regardless of the vaccine recipients HPV-infection status. Here, we describe the refinement and further potentiation of a dual-purpose HPV nanoparticle vaccine (hereafter referred to as cPANHPVAX) relying on eight different HPV L2 peptide epitopes and on the E7 oncoantigens from HPV16 and 18. cPANHPVAX not only induces anti-HPV16 E7 cytotoxic T-cell responses in C57BL/6 mice, but also anti-HPV18 E7 T-cell responses in transgenic mice with the A2.DR1 haplotype. These cytotoxic responses add up to a potent, broad-coverage humoral (HPV-neutralizing) response. cPANHPVAX safety was further improved by deletion of the pRb-binding domains of E7. Our dual-purpose vaccine holds great potential for clinical translation as an immune-treatment capable of targeting active infections as well as established HPV-related malignancies, thus benefiting both uninfected and infected individuals.

6.
Vaccines (Basel) ; 11(10)2023 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-37896984

RESUMO

Human papillomaviruses (HPVs) are a large family of viruses with a capsid composed of the L1 and L2 proteins, which bind to receptors of the basal epithelial cells and promote virus entry. The majority of sexually active people become exposed to HPV and the virus is the most common cause of cervical cancer. Vaccines are available based on the L1 protein, which self-assembles and forms virus-like particles (VLPs) when expressed in yeast and insect cells. Although very effective, these vaccines are HPV type-restricted and their costs limit broad vaccination campaigns. Recently, vaccine candidates based on the conserved L2 epitope from serotypes 16, 18, 31, 33, 35, 6, 51, and 59 were shown to elicit broadly neutralizing anti-HPV antibodies. In this study, we tested whether E. coli outer membrane vesicles (OMVs) could be successfully decorated with L2 polytopes and whether the engineered OMVs could induce neutralizing antibodies. OMVs represent an attractive vaccine platform owing to their intrinsic adjuvanticity and their low production costs. We show that strings of L2 epitopes could be efficiently expressed on the surface of the OMVs and a polypeptide composed of the L2 epitopes from serotypes 18, 33, 35, and 59 provided a broad cross-protective activity against a large panel of HPV serotypes as determined using pseudovirus neutralization assay. Considering the simplicity of the OMV production process, our work provides a highly effective and inexpensive solution to produce universal anti-HPV vaccines.

7.
NPJ Vaccines ; 7(1): 116, 2022 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-36216845

RESUMO

Skin colonization by human papillomavirus (HPV) is typically related to inconspicuous cutaneous infections without major disease or complications in immunocompetent individuals. However, in immunosuppressed patients, especially organ transplanted recipients, cutaneous HPV infections may cause massive, highly spreading and recurrent skin lesions upon synergism with UV-exposure. Current HPV prophylactic vaccines are not effective against cutaneous HPV types (cHPV). By applying a modular polytope-based approach, in this work, we explored different vaccine candidates based on selected, tandemly arranged cHPV-L2 epitopes fused to thioredoxin (Trx) as a scaffold protein. Upon conversion to heptameric nanoparticles with the use of a genetically fused oligomerization domain, our candidate Trx-L2 vaccines induce broadly neutralizing immune responses against 19 cHPV in guinea pigs. Similar findings were obtained in mice, where protection against virus challenge was also achieved via passive transfer of immune sera. Remarkably, immunization with the candidate cHPV vaccines also induced immune responses against several mucosal low- and high-risk HPV types, including HPV16 and 18. Based on cumulative immunogenicity data but also on ease and yield of production, we identified a lead vaccine candidate bearing 12 different cHPV-L2 epitopes that holds great promise as a scalable and GMP production-compatible lead molecule for the prevention of post-transplantation skin lesions caused by cHPV infection.

8.
Colloids Surf B Biointerfaces ; 217: 112669, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35810613

RESUMO

Biologically fixed arthroplasty is limited in its development by the long postoperative recovery time and the low quality of solidity of the fixed interface in the short postoperative period. Therefore, fretting stimulation is used to accelerate the combination between bone tissue and the biological fixation interface of artificial joint prostheses. The effects of different compression loads and tangential micro-motion amplitude on the growth rate of bone tissue and the firm quality of fixation interface were studied by using two kinds of micro-motion stimuli: compression and tangential micro-motion. The mechanism of micro-motion stimulation to promote bone growth at the fixation interface was revealed. The results of binding force detection of biological fixation interface and bone tissue section staining showed that the bone tissue and hydroxyapatite coating interface had the most tendency to produce new bone tissue under compression load of 4 N. In the tangential fretting environment, the tangential fretting amplitude of ± 40 µm and the normal load of 7.5 N were the most conducive to bone growth, making the combination of bone tissue and titanium alloy prosthesis coated with hydroxyapatite more firm. The study is important for accelerating the integration and shortening the rehabilitation time after artificial joint replacement.


Assuntos
Ligas , Durapatita , Desenvolvimento Ósseo , Osso e Ossos , Durapatita/farmacologia , Titânio/farmacologia
9.
Huan Jing Ke Xue ; 37(4): 1478-84, 2016 Apr 15.
Artigo em Zh | MEDLINE | ID: mdl-27548972

RESUMO

To explore the potential stressing effect of nanoscale zero-valent iron (nZVI) on denitrifying granular sludge (DGS), the evolution of DGS denitrifying performance under different C/N ratios was investigated in this study, by carrying out batch tests of eight successive periods with the nZVI shock-loading. The results showed that the specific denitrification rate of µ value decreased when the nZVI dosage was higher than 5 mg · L⁻¹. Meanwhile, a positive correlation between the inhibition ratio (IR) of µ value and substrate C/N ratios or nZVI dosage was observed. When the nZVI dosage reached 100 mg · L⁻¹, both extracellular protein and polysaccharides concentrations decreased obviously. It would be beneficial to promote the recovery of DGS denitrifying activity and reduce the COD demanding to remove unit mass of nitrate, by increasing external carbon source with C/N ratios of higher than 4. On the basis of Freundlich and Langmuir adsorption isotherms, when higher C/N ratio was provided, stronger bioadsorption of nZVI would be achieved. During the recovery period, a significant improvement of DCS denitrifying performance under the high C/N ratio was expected, due to the continuous washout of total iron in sludge phase (Qe), while the µ value would reach or approach the one of the control group when Qe was lower than 0.4 mg · g⁻¹.


Assuntos
Desnitrificação , Ferro/química , Nitratos/isolamento & purificação , Esgotos/química , Adsorção , Análise da Demanda Biológica de Oxigênio , Carbono/análise , Nitrogênio/análise
10.
Microbiology (Reading) ; 148(Pt 8): 2567-2572, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12177350

RESUMO

Several recent publications have suggested that oligo(dT) can prime reverse transcription of several mycobacterial mRNAs. To determine if this is the case for most Mycobacterium tuberculosis mRNA species, reverse transcription reactions of M. tuberculosis RNA were primed with oligo(dT) or with other primers that did not target polyadenylylated sequences, and the resultant cDNA product was evaluated. Priming with oligo(dT) yielded more cDNA than priming with an arbitrary primer for only 1 of 12 unrelated M. tuberculosis genes, as measured by competitive PCR. Priming with oligo(dT) yielded cDNA for only 30% of the genes primed for by 37 M. tuberculosis genome-directed oligonucleotides, as assessed by hybridization of cDNA with an M. tuberculosis microarray. These data demonstrate that priming of reverse transcription of mycobacterial mRNA with oligo(dT) does not yield representative samples of cDNA.


Assuntos
DNA Complementar/genética , Mycobacterium tuberculosis/genética , Oligodesoxirribonucleotídeos/metabolismo , DNA Polimerase Dirigida por RNA/metabolismo , Primers do DNA/genética , DNA Complementar/biossíntese , Regulação Bacteriana da Expressão Gênica , Mycobacterium tuberculosis/enzimologia , Análise de Sequência com Séries de Oligonucleotídeos , RNA Mensageiro/química , RNA Mensageiro/genética , Transcrição Gênica
11.
J Immunol ; 168(7): 3520-6, 2002 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-11907114

RESUMO

Mycobacterium tuberculosis-induced IFN-gamma protein and mRNA expression have been shown to be reduced in tuberculosis patients, compared with healthy tuberculin reactors. To determine whether this decrease was associated with reduced activity of the IFN-gamma promoter, we first studied binding of nuclear proteins to the radiolabeled proximal IFN-gamma promoter (-71 to -40 bp), using EMSAs with nuclear extracts of freshly isolated peripheral blood T cells. Nuclear extracts of T cells from most tuberculosis patients showed markedly reduced expression of proteins that bind to the proximal IFN-gamma promoter, compared with findings in nuclear extracts of T cells from healthy tuberculin reactors. These DNA-binding complexes contained CREB proteins, based on competitive EMSAs, supershift assays, and Western blotting with an anti-CREB Ab. Transient transfection of PBLs with a luciferase reporter construct under the control of the IFN-gamma promoter revealed reduced IFN-gamma promoter activity in tuberculosis patients. Transient transfection of Jurkat cells with a dominant-negative CREB repressor plasmid reduced IFN-gamma promoter activity. These data suggest that reduced expression of CREB nuclear proteins in tuberculosis patients results in decreased IFN-gamma promoter activity and reduced IFN-gamma production.


Assuntos
Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/biossíntese , Regulação para Baixo/imunologia , Interferon gama/genética , Líquido Intracelular/microbiologia , Proteínas Nucleares/biossíntese , Regiões Promotoras Genéticas/imunologia , Tuberculose/imunologia , Tuberculose/microbiologia , Sequência Consenso , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/antagonistas & inibidores , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/genética , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Regulação para Baixo/genética , Regulação Bacteriana da Expressão Gênica/imunologia , Humanos , Interferon gama/metabolismo , Interferon gama/fisiologia , Líquido Intracelular/imunologia , Células Jurkat , Mycobacterium tuberculosis/imunologia , NF-kappa B/metabolismo , Proteínas Nucleares/antagonistas & inibidores , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Ligação Proteica/genética , Ligação Proteica/imunologia , RNA Mensageiro/biossíntese , Linfócitos T/imunologia , Linfócitos T/metabolismo , Transfecção , Tuberculina/imunologia
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