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1.
Plant Cell ; 36(7): 2668-2688, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38581433

RESUMO

The style and stigma at the apical gynoecium are crucial for flowering plant reproduction. However, the mechanisms underlying specification of the apical gynoecium remain unclear. Here, we demonstrate that Class II TEOSINTE BRANCHED 1/CYCLOIDEA/PCF (TCP) transcription factors are critical for apical gynoecium specification in Arabidopsis (Arabidopsis thaliana). The septuple tcp2 tcp3 tcp4 tcp5 tcp10 tcp13 tcp17 (tcpSEP) and duodecuple tcp2 tcp3 tcp4 tcp5 tcp10 tcp13 tcp17 tcp24 tcp1 tcp12 tcp18 tcp16 (tcpDUO) mutants produce narrower and longer styles, while disruption of TCPs and CRABS CLAW (CRC) or NGATHAs (NGAs) in tcpDUO crc or tcpDUO nga1 nga2 nga4 causes the apical gynoecium to be replaced by lamellar structures with indeterminate growth. TCPs are predominantly expressed in the apex of the gynoecium. TCP4 interacts with CRC to synergistically upregulate the expression level of NGAs, and NGAs further form high-order complexes to control the expression of auxin-related genes in the apical gynoecium by directly interacting with TCP4. Our findings demonstrate that TCP4 physically associates with CRC and NGAs to control auxin biosynthesis in forming fine structures of the apical gynoecium.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Flores , Regulação da Expressão Gênica de Plantas , Fatores de Transcrição , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Flores/genética , Flores/metabolismo , Flores/crescimento & desenvolvimento , Mutação
2.
Anal Chem ; 96(21): 8696-8704, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38751030

RESUMO

Carbonyl sulfide (OCS) is a toxic gas produced during industrial processes that poses risks to both human health and industrial equipment. Therefore, detecting OCS concentrations plays a crucial role in early hazard warning. This paper presents an online system for detecting OCS at the ppb level using thermal conversion and spectral reconstruction filtering differential optical absorption spectroscopy (SRF-DOAS). First, OCS, which is not suitable for DOAS due to its weak absorption characteristics, is completely transformed into SO2 with strong absorption characteristics under high-temperature conditions. Then, the spectral reconstruction filtering method (SRF) is proposed to eliminate the noise and interference. The core idea of the method is to arrange the spectrum according to the spectral intensity from small to large rather than wavelength, reconstructing the spectrum into a new spectrum with linear characteristics. The reconstructed spectrum can remove noise and interference by linear fitting and retain the characteristic of SO2 oscillation absorption. Next, we demonstrate the ability of the reconstructed spectral method to remove noise and interference by comparing the spectra of the inverse-reconstructed gas mixture and SO2. The relative deviation of 0.88% at 100 ppb and detection limit of 7.26 ppb*m for OCS were obtained using the SRF-DOAS method. Finally, the reliability of the system was confirmed by measurements of OCS concentrations in mixture gas of OCS and air, as well as in human exhaled breath.

3.
Am J Pathol ; 193(5): 608-623, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36804378

RESUMO

Breast cancer is a common indication for ovarian cryopreservation. However, whether the grafting ovarian tissue meets functional requirements, as well as the need for additional interventions, remains unclear. The current study demonstrates abnormal serum hormones in breast cancer in humans and breast cancer cell line-derived tumor-bearing mice, and for the first time shows tumor-induced loss of primordial and growing follicles, and the number of follicles being lost to either growth or atresia. A gene signature of tumor-bearing mice demonstrates the disturbed regulatory network of steroidogenesis, which links to mitochondria dysfunction in oocytes and granulosa cells via the phosphatidylinositol 3-kinase signaling pathway. Notably, increased reactive oxygen species were identified in serum and ovarian tissues in tumor-bearing mice. Furthermore, supplementation with vitamin C promoted follicular quiescence, repairing tumor-induced follicle loss via inactivation of the phosphatidylinositol 3-kinase-Akt-mammalian target of rapamycin pathway, indicating the potential of antioxidants as a fertility therapy to achieve higher numbers of healthy follicles ready for ovarian cryopreservation.


Assuntos
Neoplasias da Mama , Feminino , Humanos , Animais , Camundongos , Neoplasias da Mama/metabolismo , Folículo Ovariano/metabolismo , Oócitos/metabolismo , Estresse Oxidativo , Fosfatidilinositol 3-Quinases/metabolismo , Mamíferos/metabolismo
4.
Phys Chem Chem Phys ; 26(23): 16821-16828, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38828761

RESUMO

Sulfur compounds (SO2, CS2, H2S and OCS) are common toxic pollutants in the atmospheric environment, and the absorption spectroscopy technique can indeed help to realize online monitoring of their concentrations. However, nonlinear effects that occur during absorption spectroscopy measurements have a serious impact on the measurement of the absorption cross-sections (ACSs) of sulfur compounds, leading to serious deviations in both the substance absorption properties and concentrations obtained based on ACS analysis. In this paper, the maximum effective ACSs of sulfur compounds in the linear region are obtained by considering the influence of nonlinear effects and eliminating interference factors such as oxygen and photolysis. In addition, the nonlinear effects are found to be greatly attenuated in spectra with broad band absorption characteristics by comparing the oscillatory absorption spectra before and after the differential treatment and by comparing the change in the oscillatory ACS with the broad band ACS. The experimental results show that the effective ACSs of SO2, CS2, H2S, and OCS with a resolution of 0.23 nm are 14.15 × 10-18 cm2 per molecule, 5.61 × 10-16 cm2 per molecule, 7.09 × 10-18 cm2 per molecule, and 3.20 × 10-19 cm2 per molecule, respectively. So far, it is the largest ACS obtained at room temperature and atmospheric pressure, which is of great significance for online measurement of sulfur compounds.

5.
Appl Microbiol Biotechnol ; 108(1): 333, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38739270

RESUMO

Currently, there are many different therapies available for inflammatory bowel disease (IBD), including engineered live bacterial therapeutics. However, most of these studies focus on producing a single therapeutic drug using individual bacteria, which may cause inefficacy. The use of dual drugs can enhance therapeutic effects. However, expressing multiple therapeutic drugs in one bacterial chassis increases the burden on the bacterium and hinders good secretion and expression. Therefore, a dual-bacterial, dual-drug expression system allows for the introduction of two probiotic chassis and enhances both therapeutic and probiotic effects. In this study, we constructed a dual bacterial system to simultaneously neutralize pro-inflammatory factors and enhance the anti-inflammatory pathway. These bacteria for therapy consist of Escherichia coli Nissle 1917 that expressed and secreted anti-TNF-α nanobody and IL-10, respectively. The oral administration of genetically engineered bacteria led to a decrease in inflammatory cell infiltration in colon and a reduction in the levels of pro-inflammatory cytokines. Additionally, the administration of engineered bacteria did not markedly aggravate gut fibrosis and had a moderating effect on intestinal microbes. This system proposes a dual-engineered bacterial drug combination treatment therapy for inflammatory bowel disease, which provides a new approach to intervene and treat IBD. KEY POINTS: • The paper discusses the effects of using dual engineered bacteria on IBD • Prospects of engineered bacteria in the clinical treatment of IBD.


Assuntos
Escherichia coli , Doenças Inflamatórias Intestinais , Interleucina-10 , Probióticos , Animais , Doenças Inflamatórias Intestinais/microbiologia , Doenças Inflamatórias Intestinais/terapia , Doenças Inflamatórias Intestinais/tratamento farmacológico , Camundongos , Escherichia coli/genética , Probióticos/administração & dosagem , Interleucina-10/genética , Fator de Necrose Tumoral alfa/metabolismo , Modelos Animais de Doenças , Engenharia Genética , Microbioma Gastrointestinal , Camundongos Endogâmicos C57BL , Colo/microbiologia , Colo/patologia , Citocinas/metabolismo , Anti-Inflamatórios/farmacologia
6.
Acta Biochim Biophys Sin (Shanghai) ; 56(8): 1221-1233, 2024 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-39126246

RESUMO

Immunoglobulin G (IgG) is an important serum glycoprotein and a major component of antibodies. Glycans on IgG affect the binding of IgG to the Fc receptor or complement C1q, which in turn affects the biological activity and biological function of IgG. Altered glycosylation patterns on IgG emerge as important biomarkers in the aging process and age-related diseases. Key aging-related alterations observed in IgG glycosylation include reductions in galactosylation and sialylation, alongside increases in agalactosylation, and bisecting GlcNAc. Understanding the role of IgG glycosylation in aging-related diseases offers insights into disease mechanisms and provides opportunities for the development of diagnostic and therapeutic strategies. This review summarizes five aspects of IgG: an overview of IgG, IgG glycosylation, IgG glycosylation with inflammation mediation, IgG glycan changes with normal aging, as well as the relevance of IgG glycan changes to aging-related diseases. This review provides a reference for further investigation of the regulatory mechanisms of IgG glycosylation in aging-related diseases, as well as for evaluating the potential of IgG glycosylation changes as markers of aging and aging-related diseases.


Assuntos
Envelhecimento , Imunoglobulina G , Polissacarídeos , Humanos , Glicosilação , Envelhecimento/metabolismo , Imunoglobulina G/metabolismo , Imunoglobulina G/imunologia , Polissacarídeos/metabolismo , Animais , Inflamação/metabolismo , Biomarcadores/metabolismo , Biomarcadores/sangue , Glicoproteínas
7.
Opt Lett ; 48(22): 5923-5926, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37966753

RESUMO

In this study, we determine the relationship between the broadband absorption spectroscopy and temperature using Doppler broadening combined with a multilinear shape superposition. First, a method for temperature effects on broadband absorption spectroscopy is proposed, utilizing the principle of a multiple Gaussian line shape superposition. A theoretical expression of the temperature effect on broadband spectroscopy is then presented for the first time to the best of our knowledge, and the variation law of broadband absorption spectroscopy with temperature is explained. Furthermore, the effectiveness of the expression is demonstrated by comparing experimental and theoretical data of the SO2 broadband absorption spectroscopy. The results demonstrate that the correlation coefficient (r) between the experimental and theoretical spectra of SO2 within the temperature range of 298.15-923.15 K is greater than 0.93. The method and expression presented in this Letter can effectively explain the data of previous research.

8.
Beilstein J Org Chem ; 15: 703-709, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30992717

RESUMO

A highly efficient and convenient protocol was developed to access 2-amino-4H-benzothiopyran-4-ones through a process of conjugated addition-elimination. The sulfinyl group was proved to be the optimum leaving group by thorough investigations on the elimination of sulfide, sulfinyl, and sulfonyl groups at the 2-position of benzothiopyranone. Most 2-aminobenzothiopyranones were obtained in good to excellent yields under refluxing in isopropanol within 36 h. This method is base-free and the substrate scope in terms of electronic properties of the substituents of the benzothiopyranone is broad. The ten grams scale-up synthesis of the representative compounds 4a and 4d was implemented to show the practical application of this reaction, which afforded the corresponding compounds in good yields and excellent chemical purity without requiring column chromatographical purification.

9.
Breast Cancer Res ; 16(2): R23, 2014 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-24602188

RESUMO

INTRODUCTION: Circulating tumor cells (CTCs) are commonly isolated from the blood by targeting the epithelial cell adhesion molecule (EpCAM) through positive selection. However, EpCAM can be downregulated during metastatic progression, or it can be initially not present. We designed the present prospective trial to characterize CTCs as well as other circulating cell populations in blood samples from women with metastatic breast cancer without EpCAM-dependent enrichment and/or isolation technology. METHODS: A total of 32 patients with metastatic breast cancer were enrolled, and blood samples were processed using a previously described negative depletion immunomagnetic methodology. Samples from healthy volunteers were run as controls (n = 5). Multistep sequential labeling was performed to label and fix cell-surface markers followed by permeabilization for cytokeratins (CK) 8, 18 and 19. Multiparametric flow cytometry (FCM) analysis was conducted using a BD LSR II flow cytometer or a BD FACSAria II or FACSAria III cell sorter. Immunocytochemical staining on postenrichment specimens for DAPI, EpCAM, CD45, CK, epidermal growth factor receptor and vimentin was performed. Expression of these markers was visualized using confocal microscopy (CM). RESULTS: CD45-negative/CK-positive (CD45- CK+) populations with EpCAM + and EpCAM - expression were identified with both FCM and CM from the negatively enriched patient samples. In addition, EpCAM + and EpCAM - populations that were CK + and coexpressing the pan-hematopoietic marker CD45 were also noted. There were more CK + EpCAM - events/ml than CK + EpCAM + events/ml in both the CD45- and CD45+ fractions (both statistically significant at P ≤ 0.0005). The number of CK + CD45- and CK + CD45+ events per milliliter in blood samples (regardless of EpCAM status) was higher in patient samples than in normal control samples (P ≤ 0.0005 and P ≤ 0.026, respectively). Further, a significant fraction of the CK + CD45+ events also expressed CD68, a marker associated with tumor-associated macrophages. Higher levels of CD45-CK + EpCAM - were associated with worse overall survival (P = 0.0292). CONCLUSIONS: Metastatic breast cancer patients have atypical cells that are CK + EpCAM - circulating in their blood. Because a substantial number of these patients do not have EpCAM + CTCs, additional studies are needed to evaluate the role of EpCAM - circulating cells as a prognostic and predictive marker.


Assuntos
Biomarcadores Tumorais/sangue , Neoplasias da Mama/sangue , Células Neoplásicas Circulantes/metabolismo , Adulto , Idoso , Antígenos CD/sangue , Antígenos CD/metabolismo , Antígenos de Diferenciação Mielomonocítica/sangue , Antígenos de Diferenciação Mielomonocítica/metabolismo , Antígenos de Neoplasias/sangue , Antígenos de Neoplasias/metabolismo , Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Moléculas de Adesão Celular/sangue , Moléculas de Adesão Celular/metabolismo , Linhagem Celular Tumoral , Molécula de Adesão da Célula Epitelial , Receptores ErbB/sangue , Receptores ErbB/metabolismo , Feminino , Citometria de Fluxo , Humanos , Imuno-Histoquímica , Queratina-18/sangue , Queratina-18/metabolismo , Queratina-19/sangue , Queratina-19/metabolismo , Queratina-8/sangue , Queratina-8/metabolismo , Antígenos Comuns de Leucócito/sangue , Antígenos Comuns de Leucócito/metabolismo , Células MCF-7 , Microscopia Confocal , Pessoa de Meia-Idade , Metástase Neoplásica , Prognóstico , Estudos Prospectivos , Vimentina/sangue , Vimentina/metabolismo
10.
Methods ; 64(2): 169-82, 2013 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-24056212

RESUMO

A variety of enrichment/isolation technologies exist for the characterization of rare cells in the blood of cancer patients. In this article, a negative depletion process is presented and discussed which consists of red blood cell (RBC) lysis and the subsequent removal of CD45 expressing cells through immunomagnetic depletion. Using this optimized assembly on 120 whole blood specimens, from 71 metastatic breast cancer patients, after RBC lysis, the average nucleated cell log depletion was 2.56 with a 77% recovery of the nucleated cells. The necessity of exploring different anti-CD45 antibody clones to label CD45 expressing cells in this enrichment scheme is also presented and discussed. An optimized, four-color immunofluorescence staining is conducted on the cells retained after the CD45-based immunomagnetic depletion process. Different types of rare non-hematopoietic cells are found in these enriched peripheral blood samples and a wide range of external and internal markers have been characterized, which demonstrates the range and heterogeneity of the rare cells.


Assuntos
Separação Imunomagnética/métodos , Antígenos Comuns de Leucócito/imunologia , Células Neoplásicas Circulantes/imunologia , Biomarcadores Tumorais/análise , Neoplasias da Mama/imunologia , Contagem de Células , Linhagem Celular Tumoral , Feminino , Citometria de Fluxo , Imunofluorescência , Humanos
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