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1.
Cancer Cell Int ; 24(1): 119, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38553712

RESUMO

OBJECTIVE: This study aimed to construct a model based on 23 enrolled molecules to evaluate prognoses of pT2/3N0M0 esophageal squamous cell carcinoma (ESCC) patients with up to 20 years of follow-up. METHODS: The lasso-Cox model was used to identify the candidate molecule. A nomogram was conducted to develop the survival model (molecular score, MS) based on the molecular features. Cox regression and Kaplan-Meier analysis were used in this study. The concordance index (C-index) was measured to compare the predicted ability between different models. The primary endpoint was overall survival (OS). RESULTS: A total of 226 patients and 23 proteins were enrolled in this study. Patients were classified into high-risk (MS-H) and low-risk (MS-L) groups based on the MS score of 227. The survival curves showed that the MS-L cohort had better 5-year and 10-year survival rates than the MS-H group (5-year OS: 51.0% vs. 8.0%; 10-year OS: 45.0% vs. 5.0%, all p < 0.001). Furthermore, multivariable analysis confirmed MS as an independent prognostic factor after eliminating the confounding factors (Hazard ratio 3.220, p < 0.001). The pT classification was confirmed to differentiate ESCC patients' prognosis (Log-rank: p = 0.029). However, the combination of pT and MS could classify survival curves evidently (overall p < 0.001), which showed that the prognostic prediction efficiency was improved significantly by the combination of the pT and MS than by the classical pT classification (C-index: 0.656 vs. 0.539, p < 0.001). CONCLUSIONS: Our study suggested an MS for significant clinical stratification of T2/3N0M0 ESCC patients to screen out subgroups with poor prognoses. Besides, the combination of pT staging and MS could predict survival more accurately for this cohort than the pT staging system alone.

2.
Nano Lett ; 23(14): 6727-6735, 2023 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-37459599

RESUMO

Cell migration occurs in confined microenvironments, which plays a vital role in the process of tumor metastasis. However, it is challenging to study their behaviors in vivo. Here we developed a cell squeeze system that can be scaled down to micrometers to mimic native physical confined microenvironments, wherein degrees of surface adhesion and mechanical constraints could be manipulated in order to investigate cell-migrating behaviors. Based on the microscale cell squeeze system, we found the synergistic role of lamin A/C and vimentin in cell transition and migration under strong confinement. The dynamic variations in lamin A/C and vimentin expression establish a positive feedback loop in response to confinement, effectively promoting amoeboid migration by modulating nuclear deformability while ensuring cell viability. This work shed light on modulating cell response to microenvironments by altering the expression of lamin A/C and/or vimentin, which may be a more efficient way of inhibiting cancer metastasis.


Assuntos
Movimento Celular , Lamina Tipo A , Núcleo Celular/metabolismo , Filamentos Intermediários , Lamina Tipo A/genética , Lamina Tipo A/metabolismo , Vimentina/metabolismo , Humanos , Células HeLa
3.
J Med Virol ; 95(8): e29041, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37621182

RESUMO

The emerging outbreak of monkeypox is closely associated with the viral infection and spreading, threatening global public health. Virus-induced cell migration facilitates viral transmission. However, the mechanism underlying this type of cell migration remains unclear. Here we investigate the motility of cells infected by vaccinia virus (VACV), a close relative of monkeypox, through combining multi-omics analyses and high-resolution live-cell imaging. We find that, upon VACV infection, the epithelial cells undergo epithelial-mesenchymal transition-like transformation, during which they lose intercellular junctions and acquire the migratory capacity to promote viral spreading. After transformation, VACV-hijacked RhoA signaling significantly alters cellular morphology and rearranges the actin cytoskeleton involving the depolymerization of robust actin stress fibers, leading-edge protrusion formation, and the rear-edge recontraction, which coordinates VACV-induced cell migration. Our study reveals how poxviruses alter the epithelial phenotype and regulate RhoA signaling to induce fast migration, providing a unique perspective to understand the pathogenesis of poxviruses.


Assuntos
Mpox , Vaccinia virus , Humanos , Movimento Celular , Surtos de Doenças , Células Epiteliais
4.
FASEB J ; 34(1): 446-457, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31914682

RESUMO

Mechanical damage or infection to the endometrium can lead to the formation of adhesions in the uterine cavity, which may result in reduced reproductive outcome and/or pregnancy complications. The prognosis of this disease is poor due to few effective treatments and the complex environment of endometrium. Heparin-Poloxamer Hydrogel (HP hydrogel) is a nontoxic and biodegradable biomaterial, which has been commonly used as a sustained-release delivery system. In this study, we applied a mini-endometrial curette to scrape the endometrium of rats to mimic the process of curettage in patients. After the establishment of IUA model in rats, we injected the thermo-sensitive hydrogel(E2-HP hydrogel) into the injured uterine cavity and evaluated the therapeutic effect of E2-HP hydrogel on the recovery of IUA. Our results showed that E2-HP hydrogel can significantly facilitate the regeneration of injured endometrium along with inhibiting the cell apoptosis in IUA model. Furthermore, we revealed that E2-HP hydrogel on the recovery of IUA was closely associated with the upregulation of kisspeptin through activating the ERK1/2 and MAPKs p38 pathways. In conclusion, E2-HP hydrogel can effectively transfer E2 into the injured endometrium and it can be considered as a promising therapeutic method for the women with intrauterine adhesions.


Assuntos
Endométrio/citologia , Estradiol/farmacologia , Heparina/química , Hidrogéis/farmacologia , Poloxâmero/química , Regeneração , Aderências Teciduais/tratamento farmacológico , Útero/citologia , Animais , Endométrio/efeitos dos fármacos , Endométrio/lesões , Estradiol/química , Feminino , Hidrogéis/química , Gravidez , Ratos , Ratos Sprague-Dawley , Recuperação de Função Fisiológica , Útero/efeitos dos fármacos , Útero/lesões
5.
Phys Chem Chem Phys ; 22(30): 17229-17235, 2020 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-32685948

RESUMO

Compared with the conventional magnetic means (such as ferromagnetic contacts), controlling a spin current by electrical methods could largely reduce the energy consumption and dimensions of nano-devices, which has become a focus of research in spintronics. Inspired by recent progress in the synthesis of an iron-based metal-organic nanostructure, we investigate the spin-dependent electronic transport of the molecule of Fe3-terpyridine-phenyl-phenyl-terpyridine-Fe3 (Fe3-TPPT-Fe3) through first-principles calculations, and propose a three-terminal device without ferromagnetics. By applying a gate voltage, not only the spin polarization can be switched between 100% and -100% to achieve a dual-spin filter, but also its fine regulation can be realized, where the transmission with any ratio of spin-up to spin-down electron numbers is achievable. Analysis shows that the particular transmission spectra are the key mechanism, where two peaks reside discretely on both sides of the Fermi level with opposite spins. Such a feature is found to be robust to the number of Fe atoms and TPPT chain length, suggesting that it is an intrinsic feature of such systems and very conducive to practical applications. The electrical control (such as an electric field) of spin polarization is realized at the single-molecule level, showing great application potential.

6.
FASEB J ; 32(5): 2492-2506, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29273674

RESUMO

Asparagine ( N)-linked glycosylation requires the ordered, stepwise synthesis of lipid-linked oligosaccharide (LLO) precursor Glc3Man9GlcNAc2-pyrophosphate-dolichol (Glc3Man9Gn2-PDol) on the endoplasmic reticulum. The fourth and fifth steps of LLO synthesis are catalyzed by Alg2, an unusual mannosyltransferase (MTase) with two different MTase activities; Alg2 adds both an α1,3- and α1,6-mannose onto ManGlcNAc2-PDol to form the trimannosyl core Man3GlcNAc2-PDol. The biochemical properties of Alg2 are controversial and remain undefined. In this study, a liquid chromatography/mass spectrometry-based quantitative assay was established and used to analyze the MTase activities of purified yeast Alg2. Alg2-dependent Man3GlcNAc2-PDol production relied on net-neutral lipids with a propensity to form bilayers. We further showed addition of the α1,3- and α1,6-mannose can occur independently in either order but at differing rates. The conserved C-terminal EX7E motif, N-terminal cytosolic tail, and 3 G-rich loop motifs in Alg2 play crucial roles for these activities, both in vitro and in vivo. These findings provide insight into the unique bifunctionality of Alg2 during LLO synthesis and lead to a new model in which alternative, independent routes exist for Alg2 catalysis of the trimannosyl core oligosaccharide.-Li, S.-T., Wang, N., Xu, X.-X., Fujita, M., Nakanishi, H., Kitajima, T., Dean, N., Gao, X.-D. Alternative routes for synthesis of N-linked glycans by Alg2 mannosyltransferase.


Assuntos
Polissacarídeos Fúngicos/química , Bicamadas Lipídicas/química , Manosiltransferases/química , Modelos Moleculares , Oligossacarídeos/química , Proteínas de Saccharomyces cerevisiae/química , Saccharomyces cerevisiae/enzimologia , Motivos de Aminoácidos , Polissacarídeos Fúngicos/genética , Polissacarídeos Fúngicos/metabolismo , Glicosilação , Bicamadas Lipídicas/metabolismo , Manosiltransferases/genética , Manosiltransferases/metabolismo , Oligossacarídeos/metabolismo , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Relação Estrutura-Atividade
7.
Glycobiology ; 28(10): 741-753, 2018 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-29939232

RESUMO

In eukaryotes, the biosynthesis of a highly conserved dolichol-linked oligosaccharide (DLO) precursor Glc3Man9GlcNAc2-pyrophosphate-dolichol (PP-Dol) begins on the cytoplasmic face of the endoplasmic reticulum (ER) and ends within the lumen. Two functionally distinguished heteromeric glycosyltransferase (GTase) complexes are responsible for the cytosolic DLO assembly. Alg1, a ß-1, 4 mannosyltransferase (MTase) physically interacts with Alg2 and Alg11 proteins to form the multienzyme complex which catalyzes the addition of all five mannose to generate the Man5GlcNAc2-PP-Dol intermediate. Despite the fact that Alg1 plays a central role in the formation of the multi-MTase has been confirmed, the topological information of Alg1 including the molecular mechanism of membrane association are still poorly understood. Using a combination of bioinformatics and biological approaches, we have undertaken a structural and functional study on Alg1 protein, in which the enzymatic activities of Alg1 and its variants were monitored by a complementation assay using the GALpr-ALG1 yeast strain, and further confirmed by a liquid chromatography-mass spectrometry-based in vitro quantitative assay. Computational and experimental evidence confirmed Alg1 shares structure similarity with Alg13/14 complex, which has been defined as a membrane-associated GT-B GTase. Particularly, we provide clear evidence that the N-terminal transmembrane domain including the following positively charged amino acids and an N-terminal amphiphilic-like α helix domain exposed on the protein surface strictly coordinate the Alg1 orientation on the ER membrane. This work provides detailed membrane topology of Alg1 and further reveals its biological importance at the spatial aspect in coordination of cytosolic DLO biosynthesis.


Assuntos
Membrana Celular/metabolismo , Dolicóis/biossíntese , Manosiltransferases/metabolismo , Oligossacarídeos/biossíntese , Saccharomyces cerevisiae/metabolismo , Membrana Celular/química , Dolicóis/química , Manosiltransferases/química , Manosiltransferases/genética , Oligossacarídeos/química , Conformação Proteica , Saccharomyces cerevisiae/citologia
8.
Yeast ; 35(2): 225-236, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29027702

RESUMO

In eukaryotes, the glycosylphosphatidylinositol (GPI) modification of many glycoproteins on the cell surface is highly conserved. The lipid moieties of GPI-anchored proteins undergo remodelling processes during their maturation. To date, the products of the PER1, GUP1 and CWH43 genes of the yeast Saccharomyces cerevisiae have been shown to be involved in the lipid remodelling. Here, we focus on the putative GPI remodelling pathway in the methylotrophic yeast Ogataea minuta. We found that the O. minuta homologues of PER1, GUP1 and CWH43 are functionally compatible with those of S. cerevisiae. Disruption of GUP1 or CWH43 in O. minuta caused a growth defect under non-permissive conditions. The O. minuta per1Δ mutant exhibited a more fragile phenotype than the gup1Δ or cwh43Δ mutants. To address the role of GPI modification in O. minuta, we assessed the effect of these mutations on the processing and localization of the O. minuta homologues of the Gas1 protein; in S. cerevisiae, Gas1p is an abundant and well-characterized GPI-anchored protein. We found that O. minuta possesses two copies of the GAS1 gene, which we designate GAS1A and GAS1B. Microscopy and western blotting analysis showed mislocalization and/or lower retention of Gas1Ap and Gas1Bp within the membrane fraction in per1Δ or gup1Δ mutant cells, suggesting the significance of lipid remodelling for GPI-anchored proteins in O. minuta. Localization behaviour of Gas1Bp differed from that of Gas1Ap. Our data reveals, for the first time (to our knowledge), the existence of genes related to GPI anchor remodelling in O. minuta cells.


Assuntos
Parede Celular/metabolismo , Proteínas Fúngicas/metabolismo , Leveduras/metabolismo , Sequência de Aminoácidos , Parede Celular/química , Proteínas Fúngicas/genética , Regulação Fúngica da Expressão Gênica
9.
Inflamm Res ; 66(2): 187-196, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27900412

RESUMO

OBJECTIVE: The activation of NF-κB signaling and unbalance of T-helper (Th) cells have been reported to play a key role in the pathogenesis of colitis. Cortex Phellodendri Chinensis (CPC) is commonly used to treat inflammation and diarrhea. Demethyleneberberine (DMB), a component of CPC, was reported to treat alcoholic liver disease as a novel natural mitochondria-targeted antioxidant in our previous study. In this study, we investigated whether DMB could protect against dextran sulfate sodium (DSS)-induced inflammatory colitis in mice by regulation of NF-κB pathway and Th cells homeostatis. METHODS: Inflammatory colitis mice were induced by 3% DSS, and DMB were orally administered on the doses of 150 and 300 mg/kg. In vitro, DMB (10, 20, 40 µM) and N-acetyl cysteine (NAC, 5 mM) were co-cultured with RAW264.7 for 2 h prior to lipopolysaccharide (LPS) stimulation, and splenocytes from the mice were cultured ex vivo for 48 h for immune response test. RESULTS: In vivo, DMB significantly alleviated the weight loss and diminished myeloperoxidase (MPO) activity, while significantly reduced the production of pro-inflammatory cytokines, such as interleukin (IL)-6 and tumor necrosis factor-α (TNF-α), and inhibited the activation of NF-κB signaling pathway. Furthermore, DMB decreased interferon (IFN)-γ, increased IL-4 concentration in the mice splenocytes and the ratio of IgG1/IgG2a in the serum. In vitro, ROS production and pro-inflammation cytokines were markedly inhibited by DMB in RAW264.7 cell. CONCLUSIONS: Our findings revealed that DMB alleviated mice colitis and inhibited the inflammatory responses by inhibiting NF-κB pathway and regulating the balance of Th cells.


Assuntos
Anti-Inflamatórios/farmacologia , Berberina/análogos & derivados , Doenças Inflamatórias Intestinais/imunologia , NF-kappa B/antagonistas & inibidores , Linfócitos T Auxiliares-Indutores/efeitos dos fármacos , Animais , Anti-Inflamatórios/uso terapêutico , Berberina/farmacologia , Berberina/uso terapêutico , Colo/efeitos dos fármacos , Colo/imunologia , Colo/patologia , Citocinas/imunologia , Sulfato de Dextrana , Feminino , Homeostase/efeitos dos fármacos , Imunoglobulina G/sangue , Doenças Inflamatórias Intestinais/sangue , Doenças Inflamatórias Intestinais/induzido quimicamente , Doenças Inflamatórias Intestinais/tratamento farmacológico , Camundongos , Camundongos Endogâmicos C57BL , NF-kappa B/imunologia , Células RAW 264.7 , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos , Baço/citologia , Linfócitos T Auxiliares-Indutores/imunologia
10.
Chemistry ; 21(9): 3821-30, 2015 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-25641070

RESUMO

To improve the photocatalytic properties of coordination polymers under irradiation in the visible-light region, coordination polymer nanobelts (CPNB) were loaded on functional carbon fiber (FCF) through the use of a simple colloidal blending process. The resulting coordination polymer nanobelt loaded functional carbon fiber composite material (CPNB/FCF) exhibited dramatically improved photocatalytic activity for the degradation of rhodamine B (RhB) under visible-light irradiation. Optical and electrochemical methods illustrated the enhanced photocatalytic activity of CPNB/FCF originated from high separation efficiency of photogenerated electrons and holes on the interface of CPNB and FCF, which was produced by the synergy effect between them. In the composite material, the role of FCF could be described as photosensitizer and good electron transporter. For FCF, the number of functional groups on its surface has a significant influence on the photocatalytic performance of the resulting CPNB/FCF composite material, and an ideal FCF carrier was obtained as a highly efficient CPNB/FCF photocatalyst. CPNB/FCF showed outstanding stability during the degradation of rhodamine B (RhB); thus, the material is suitable for use as a photocatalyst in the treatment of organic dyes in water.

12.
Talanta ; 277: 126415, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38878513

RESUMO

Endothelial cells (ECs) migration is a crucial early step in vascular repair and tissue neovascularization. While extensive research has elucidated the biochemical drivers of endothelial motility, the impact of biophysical cues, including vessel geometry and topography, remains unclear. Herein, we present a novel approach to reconstruct 3D self-assembly blood vessels-on-a-chip that accurately replicates real vessel geometry and topography, surpassing conventional 2D flat tube formation models. This vessels-on-a-chip system enables real-time monitoring of vasculogenesis and ECs migration at high spatiotemporal resolution. Our findings reveal that ECs exhibit increased migration speed and directionality in response to narrower vessel geometries, transitioning from a rounded to a polarized morphology. These observations underscore the critical influence of vessel size in regulating ECs migration and morphology. Overall, our study highlights the importance of biophysical factors in shaping ECs behavior, emphasizing the need to consider such factors in future studies of endothelial function and vessel biology.


Assuntos
Vasos Sanguíneos , Movimento Celular , Células Endoteliais da Veia Umbilical Humana , Humanos , Vasos Sanguíneos/citologia , Vasos Sanguíneos/fisiologia , Células Endoteliais/citologia , Dispositivos Lab-On-A-Chip , Neovascularização Fisiológica
13.
Ann Surg Oncol ; 20(3): 828-35, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22990647

RESUMO

BACKGROUND: Reconstruction rates after mastectomy have been reported to range from 25-40%; however, most studies have focused on patients treated in an inpatient setting. We sought to determine the utilization of outpatient mastectomy and use of breast reconstruction in Southern California. METHODS: Postmastectomy reconstruction rates were determined from the California Office of Statewide Health Planning and Development database from 2006-2009 using CPT codes and similarly from an inpatient database using ICD-9 codes. Reconstruction rates were compared between the inpatient and outpatient setting. For the outpatient setting, univariate and multivariate odds ratios with 95% confidence intervals were estimated for relative odds of immediate reconstruction versus mastectomy alone. RESULTS: The percentage of patients undergoing outpatient mastectomy ranged from 20.4 to 23.9% of the total number of all patients undergoing mastectomy. Whereas immediate inpatient reconstruction increased from 29.2 to 41.6% (overall rate 35.5%), the proportion of outpatients undergoing reconstruction only increased from 7.7 to 10.3% (overall rate 9.1%). Similar to the inpatient setting, in multivariate analysis, age, insurance status, race/ethnicity, and type of hospital were significantly associated with the use of reconstruction in the outpatient setting. CONCLUSIONS: A substantial number of patients undergo outpatient mastectomy with low rates of reconstruction. Although the choice of an outpatient mastectomy may certainly represent a selection bias for those not choosing reconstruction, an increase in the use of outpatient mastectomy may result in decreases in the use of postmastectomy reconstruction.


Assuntos
Neoplasias da Mama/cirurgia , Carcinoma Intraductal não Infiltrante/cirurgia , Mamoplastia/estatística & dados numéricos , Mastectomia/estatística & dados numéricos , Pacientes Ambulatoriais/estatística & dados numéricos , Adulto , Neoplasias da Mama/classificação , Neoplasias da Mama/patologia , Carcinoma Intraductal não Infiltrante/classificação , Carcinoma Intraductal não Infiltrante/patologia , Feminino , Seguimentos , Humanos , Classificação Internacional de Doenças , Pessoa de Meia-Idade , Invasividade Neoplásica , Estadiamento de Neoplasias , Prognóstico
16.
Mitochondrial DNA B Resour ; 7(10): 1766-1767, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36212091

RESUMO

Spondias dulcis is a deciduous tree in the family Anacardiaceae. The species originates in South America and now is widely cultivated in tropical areas due to its edible fruits. In this study, we find that the length of the complete plastome of S. dulcis is 162,256 bp. It includes 35 tRNA genes and eight rRNA genes, 86 protein-coding genes and totally 130 genes. The complete plastome of S. dulcis includes a small single-copy (SSC) region of 18,459 bp, a large single-copy (LSC) region of 89,353 bp, and two inverted repeats (IRs) regions of 27,222 bp. The total G/C content of S. dulcis is 37.7%. It shows that S. dulcis is closely related to S. mombin within Anacardiaceae. It will contribute to the conservation genetics of S. dulcis and the phylogenetic studies in Anacardiaceae.

17.
Artigo em Inglês | MEDLINE | ID: mdl-35805692

RESUMO

"Soundscape" is defined as "an acoustic environment as perceived or experienced and/or understood by a person or people, in context." The research focuses on the physical properties of sound, paying attention to the relationship between the soundscape and people. Sports provide a comprehensive context, including the athletes, their behavior, the environment, spectators, and other elements. Soundscape in sports has many important functions, such as indicating the movement process, promoting positive emotions, and enhancing the entertainment atmosphere. It is also related to the physical and mental health of people who are exercising. As a technical sport with multidimensional soundscape qualities, diabolo is very popular among older adults in China due to its easy portability and operation. In order to explore the influence mechanism of the soundscape on the mental health of older players and better guide the shaping of soundscapes at sports venues, this paper focuses on soundscape perception and proposes a two-channel (direct and indirect) model of the influence of the diabolo soundscape on the psychological perception of older players. At the same time, we introduce the flow state as an indicator to evaluate mental health, and use the Short Flow State Scale (SFSS) to measure the flow state. By setting up a control experiment using the diabolo with and without sound and using the two-channel (direct and indirect) influence model to compare the differences in flow state scores under the two states, we analyzed the influence mechanism of the diabolo soundscape on the flow state of elderly groups. The results show that the scores of various flow state dimensions and total flow scores in the silent state of diabolo exercise are significantly lower than those in the sound state (p < 0.05 and p < 0.001), and the main differences are in the three dimensions of unambiguous feedback, sense of control, and autotelic experience. The two-channel influence model can effectively explain the differences in older adults' flow state, which provides a new comprehensive perspective to study the effect of the soundscape in sports on people's mental health.


Assuntos
Acústica , Som , Idoso , China , Exercício Físico , Humanos , Saúde Mental
18.
Commun Biol ; 5(1): 117, 2022 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-35136180

RESUMO

N-glycosylation starts with the biosynthesis of lipid-linked oligosaccharide (LLO) on the endoplasmic reticulum (ER). Alg2 mannosyltransferase adds both the α1,3- and α1,6-mannose (Man) onto ManGlcNAc2-pyrophosphate-dolichol (M1Gn2-PDol) in either order to generate the branched M3Gn2-PDol product. The well-studied yeast Alg2 interacts with ER membrane through four hydrophobic domains. Unexpectedly, we show that Alg2 structure has diverged between yeast and humans. Human Alg2 (hAlg2) associates with the ER via a single membrane-binding domain and is markedly more stable in vitro. These properties were exploited to develop a liquid chromatography-mass spectrometry quantitative kinetics assay for studying purified hAlg2. Under physiological conditions, hAlg2 prefers to transfer α1,3-Man onto M1Gn2 before adding the α1,6-Man. However, this bias is altered by an excess of GDP-Man donor or an increased level of M1Gn2 substrate, both of which trigger production of the M2Gn2(α-1,6)-PDol. These results suggest that Alg2 may regulate the LLO biosynthetic pathway by controlling accumulation of M2Gn2 (α-1,6) intermediate.


Assuntos
Manosiltransferases , Proteínas de Saccharomyces cerevisiae , Vias Biossintéticas , Dolicóis/metabolismo , Humanos , Lipopolissacarídeos , Manosiltransferases/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo
19.
Biosens Bioelectron ; 217: 114709, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36115123

RESUMO

Osteosarcoma is one of the most frequent primary sarcoma of bone among adolescents. Early diagnosis of osteosarcoma is the key factor to achieve high survival rate of patients. Nevertheless, traditional histological biopsy is highly invasive and associated with the risk of arousing tumor spread. Herein, we develop a method integrating microfluidics and surface-enhanced Raman spectroscopy (SERS) to isolate plasma-derived exosomes and profile multiple exosomal biomarkers for the diagnosis of osteosarcoma. The method showed highly efficient isolation of exosomes directly from human plasma and can profile exosomes based on protein biomarkers, with the detection limit down to 2 exosomes per µL. The whole assay can be performed in 5 h and only consumed 50 µL of plasma for one analysis. With the method, we analyzed the level of three protein biomarkers, i.e., CD63, vimentin (VIM) and epithelial cell adhesion molecule (EpCAM), on plasma-derived exosomes from 20 osteosarcoma patients and 20 heathy controls. Significantly higher levels of CD63, VIM and EpCAM were observed on plasma exosomes from the osteosarcoma patients compared to the healthy controls. Based on the level of the exosomal biomarkers, a classification model was built for the rapid diagnosis of osteosarcoma, with the sensitivity, specificity and accuracy of 100%, 90% and 95%, respectively. The proposed method does not require complex operations nor expensive equipment, and has great promise in clinical diagnosis of cancer as a liquid biopsy technique.


Assuntos
Técnicas Biossensoriais , Neoplasias Ósseas , Exossomos , Osteossarcoma , Adolescente , Biomarcadores Tumorais , Neoplasias Ósseas/diagnóstico , Neoplasias Ósseas/metabolismo , Molécula de Adesão da Célula Epitelial/análise , Exossomos/química , Humanos , Microfluídica/métodos , Osteossarcoma/diagnóstico , Osteossarcoma/metabolismo , Vimentina/análise , Vimentina/metabolismo
20.
Ann Surg Oncol ; 18(8): 2158-65, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21308486

RESUMO

BACKGROUND: Many factors influence whether breast cancer patients undergo reconstruction after mastectomy. We sought to determine the patterns of care and variables associated with the use of breast reconstruction in Southern California. MATERIALS AND METHODS: Postmastectomy reconstruction rates were determined from the California Office of Statewide Health Planning and Development (OSHPD) inpatient database from 2003 to 2007. International Classification of Disease-9 codes were used to identify patients undergoing reconstruction after mastectomy. Changes in reconstruction rates were examined by calendar year, age, race, type of insurance, and type of hospital using a chi-square test. Univariate and multivariate odds ratios (OR) with 95% confidence intervals (95% CI) were estimated for relative odds of immediate reconstruction versus mastectomy only. RESULTS: In multivariate analysis, calendar year, age, race, type of insurance, and type of hospital were statistically significantly associated with use of reconstruction. The proportion of patients undergoing reconstruction rose from 24.8% in 2003 to 29.2% in 2007. Patients with private insurance were 10 times more likely to undergo reconstruction than patients with Medi-Cal insurance (OR 9.95, 95% CI 8.46-11.70). African American patients were less likely (OR 0.58, 95% CI 0.46-0.73) and Asian patients one-third as likely (OR 0.37, 95% CI 0.29-0.47) to undergo reconstruction as Caucasians patients Most reconstructive procedures were performed at teaching hospitals and designated cancer centers. CONCLUSIONS: Although the rate of postmastectomy reconstruction is increasing, only a minority of patients undergo reconstruction. Age, race, type of insurance, and type of hospital appear to be significant factors limiting the use of reconstruction.


Assuntos
Neoplasias da Mama/cirurgia , Etnicidade/estatística & dados numéricos , Disparidades nos Níveis de Saúde , Disparidades em Assistência à Saúde , Mamoplastia/estatística & dados numéricos , Mastectomia , Adulto , Negro ou Afro-Americano , Idoso , Idoso de 80 Anos ou mais , Asiático , Neoplasias da Mama/psicologia , California , Estudos de Coortes , Etnicidade/psicologia , Feminino , Seguimentos , Hispânico ou Latino , Humanos , Mamoplastia/psicologia , Pessoa de Meia-Idade , Planejamento de Assistência ao Paciente , Estudos Prospectivos , Taxa de Sobrevida , Resultado do Tratamento , População Branca
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