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1.
Gastric Cancer ; 27(2): 343-354, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38095766

RESUMO

OBJECTIVE: Patients with gastric atrophy and intestinal metaplasia (IM) were at risk for gastric cancer, necessitating an accurate risk assessment. We aimed to establish and validate a diagnostic approach for gastric biopsy specimens using deep learning and OLGA/OLGIM for individual gastric cancer risk classification. METHODS: In this study, we prospectively enrolled 545 patients suspected of atrophic gastritis during endoscopy from 13 tertiary hospitals between December 22, 2017, to September 25, 2020, with a total of 2725 whole-slide images (WSIs). Patients were randomly divided into a training set (n = 349), an internal validation set (n = 87), and an external validation set (n = 109). Sixty patients from the external validation set were randomly selected and divided into two groups for an observer study, one with the assistance of algorithm results and the other without. We proposed a semi-supervised deep learning algorithm to diagnose and grade IM and atrophy, and we compared it with the assessments of 10 pathologists. The model's performance was evaluated based on the area under the curve (AUC), sensitivity, specificity, and weighted kappa value. RESULTS: The algorithm, named GasMIL, was established and demonstrated encouraging performance in diagnosing IM (AUC 0.884, 95% CI 0.862-0.902) and atrophy (AUC 0.877, 95% CI 0.855-0.897) in the external test set. In the observer study, GasMIL achieved an 80% sensitivity, 85% specificity, a weighted kappa value of 0.61, and an AUC of 0.953, surpassing the performance of all ten pathologists in diagnosing atrophy. Among the 10 pathologists, GasMIL's AUC ranked second in OLGA (0.729, 95% CI 0.625-0.833) and fifth in OLGIM (0.792, 95% CI 0.688-0.896). With the assistance of GasMIL, pathologists demonstrated improved AUC (p = 0.013), sensitivity (p = 0.014), and weighted kappa (p = 0.016) in diagnosing IM, and improved specificity (p = 0.007) in diagnosing atrophy compared to pathologists working alone. CONCLUSION: GasMIL shows the best overall performance in diagnosing IM and atrophy when compared to pathologists, significantly enhancing their diagnostic capabilities.


Assuntos
Aprendizado Profundo , Gastrite Atrófica , Neoplasias Gástricas , Humanos , Gastrite Atrófica/diagnóstico , Gastrite Atrófica/patologia , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/patologia , Gastroscopia/métodos , Biópsia/métodos , Fatores de Risco , Atrofia , Metaplasia/diagnóstico por imagem
2.
Environ Toxicol ; 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38597597

RESUMO

Cervical squamous cell carcinoma (CESC), one of the most common malignancies in women, imposes a significant burden on women's health worldwide. Despite extensive research, the molecular and pathogenic mechanisms of cervical squamous cell carcinoma and CESC remain unclear. This study aimed to explore the immune-related genes, immune microenvironment infiltration, and prognosis of CESC, providing a theoretical basis for guiding clinical treatment. Initially, by mining four gene sets and immune-related gene sets from public databases, 14 immune-related genes associated with CESC were identified. Through univariate and multivariate COX regression analyses, as well as lasso regression analysis, four CESC-independent prognostic genes were identified, and a prognostic model was constructed, dividing them into high and low-risk groups. The correlation between these genes and immune cells and immune functions were explored through ssGSEA enrichment analysis, revealing a close association between the high-risk group and processes such as angiogenesis and epithelial-mesenchymal transition. Furthermore, using public databases and qRT-PCR experiments, significant differences in CXCL8 expression between normal cervical cells and cervical cancer cells were discovered. Subsequently, a CXCL8 knockdown plasmid was constructed, and the efficiency of CXCL8 knockdown was validated in two CESC cell lines, MEG-01 and HCE-1. Through CCK-8, scratch, and Transwell assays, it was confirmed that CXCL8 knockdown could inhibit the proliferation, invasion, and migration abilities of CESC cells. Targeting CXCL8 holds promise for personalized therapy for CESC, providing a strong theoretical basis for achieving clinical translation.

3.
Molecules ; 29(11)2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38893411

RESUMO

The symbiotic relationship between nitrogen-fixing cyanobacteria and plants offers a promising avenue for sustainable agricultural practices and environmental remediation. This review paper explores the molecular interactions between nitrogen-fixing cyanobacteria and nanoparticles, shedding light on their potential synergies in agricultural nanotechnology. Delving into the evolutionary history and specialized adaptations of cyanobacteria, this paper highlights their pivotal role in fixing atmospheric nitrogen, which is crucial for ecosystem productivity. The review discusses the unique characteristics of metal nanoparticles and their emerging applications in agriculture, including improved nutrient delivery, stress tolerance, and disease resistance. It delves into the complex mechanisms of nanoparticle entry into plant cells, intracellular transport, and localization, uncovering the impact on root-shoot translocation and systemic distribution. Furthermore, the paper elucidates cellular responses to nanoparticle exposure, emphasizing oxidative stress, signaling pathways, and enhanced nutrient uptake. The potential of metal nanoparticles as carriers of essential nutrients and their implications for nutrient-use efficiency and crop yield are also explored. Insights into the modulation of plant stress responses, disease resistance, and phytoremediation strategies demonstrate the multifaceted benefits of nanoparticles in agriculture. Current trends, prospects, and challenges in agricultural nanotechnology are discussed, underscoring the need for responsible and safe nanoparticle utilization. By harnessing the power of nitrogen-fixing cyanobacteria and leveraging the unique attributes of nanoparticles, this review paves the way for innovative, sustainable, and efficient agricultural practices.


Assuntos
Agricultura , Cianobactérias , Nanotecnologia , Fixação de Nitrogênio , Cianobactérias/metabolismo , Nanotecnologia/métodos , Agricultura/métodos , Nanopartículas Metálicas/química , Nitrogênio/metabolismo , Simbiose , Nanopartículas/química
4.
Infect Immun ; 90(1): e0058521, 2022 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-34748368

RESUMO

Upon recognition of pathogen components by pattern recognition receptors, cells could be activated to produce inflammatory cytokines and type I interferons. The inflammation is tightly modulated by the host to prevent inappropriate inflammatory responses. MicroRNAs (miRNAs) are noncoding small RNAs that can inhibit gene expression and participate in various biological functions, including maintaining a balanced immune response in the host. To maintain the balance of the immune response, these pathways are closely regulated by the host to prevent inappropriate reactions of the cells. However, in lower vertebrates, the miRNA-mediated inflammatory response regulatory networks remain largely unknown. Here, we report that two miRNAs, i.e., miR-20-1 and miR-101a, were identified as negative regulators in teleost inflammatory responses. Initially, we found that both miR-20-1 and miR-101a dramatically increased after lipopolysaccharide (LPS) stimulation and Vibrio harveyi infection. Upregulated miR-20-1 and miR-101a inhibited LPS-induced inflammatory cytokine production by targeting tumor necrosis factor receptor-associated factor 6 (TRAF6), thus avoiding excessive inflammation. Moreover, miR-20-1 and miR-101a regulate the inflammatory responses through the TRAF6-mediated NF-κB signaling pathway. Collectively, these data indicate that miR-20-1 and miR-101a act as negative regulators by regulating the TRAF6-mediated NF-κB signaling pathway and participate in host antibacterial immune responses, which will provide new insights into the intricate networks of the host-pathogen interactions in the lower vertebrates.


Assuntos
Doenças dos Peixes/etiologia , Doenças dos Peixes/metabolismo , Inflamação/veterinária , MicroRNAs/genética , NF-kappa B/metabolismo , Perciformes/genética , Perciformes/metabolismo , Fator 6 Associado a Receptor de TNF/genética , Animais , Citocinas/metabolismo , Regulação da Expressão Gênica , Técnicas de Silenciamento de Genes , Interações Hospedeiro-Patógeno/genética , Interações Hospedeiro-Patógeno/imunologia , Humanos , Mediadores da Inflamação/metabolismo , Lipopolissacarídeos/efeitos adversos , Modelos Biológicos , Interferência de RNA , Transdução de Sinais
5.
Microb Pathog ; 142: 104044, 2020 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-32032766

RESUMO

Bacterial non-coding RNAs (ncRNAs) can participate in multiple biological processes, including motility, biofilm formation, and virulence. Using high-throughput sequencing and transcriptome analysis of Salmonella enterica serovar Typhi (S. Typhi), we identified a novel antisense RNA located at the opposite strand of the flhDC operon. In this study, a northern blot and qRT-PCR were used to confirm the expression of this newfound antisense RNA in S. Typhi. Moreover, 5' RACE and 3' RT-PCR were performed to reveal the molecular characteristics of the antisense RNA, which was 2079 nt - 2179 nt in length, covered the entire flhDC operon sequence, and termed AsfD. The level of AsfD expression was higher during the stationary phase of S. Typhi and activated by the regulators, OmpR and Fis. When AsfD was overexpressed, the level of flagellar gene flhDC transcription increased; moreover, the level of fliA and fljB expression, as well as the motility and biofilm formation of S. Typhi were also enhanced. The results of this study suggest that AsfD is likely to enhance the motility and biofilm formation of S. Typhi by up-regulating flhDC expression.

6.
Arch Microbiol ; 201(1): 17-25, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30173343

RESUMO

In response to environmental changes, Anabaena cylindrica differentiate three cell types: vegetative cells for photosynthesis, heterocysts for nitrogen fixation, and akinetes for stress survival. Cell-surface polysaccharides play important roles in cyanobacterial ecophysiology. In this study, specific cell-surface sugars were discovered in heterocysts, akinetes and vegetative cells of A. cylindrica using 20 fluorescein-labeled lectins. Both N-acetylglucosamine-binding lectins WGA and succinylated WGA bound specifically to the vegetative cells. Akinetes bound to three mannose-binding lectins (LCA, PSA, and ConA), and one of the galactose-binding lectins (GSL-I). Heterocyst also bound to ConA. However, the heterocysts in all4388 mutant of Anabaena sp. PCC 7120, in which the putative polysaccharide export protein gene all4388 was disrupted, exhibited diminished binding to ConA. Identification of distinct cell-surface sugar helped us to understand the role of polysaccharide for each cell type. Fluorescence-activated cell sorting may be applicable in isolating each cell type for comparative "omics" studies among the three cell types.


Assuntos
Anabaena cylindrica/metabolismo , Transporte Biológico/fisiologia , Fixação de Nitrogênio/genética , Fotossíntese/genética , Polissacarídeos Bacterianos/metabolismo , Anabaena cylindrica/genética , Proteínas de Bactérias/genética , Transporte Biológico/genética , Concanavalina A/metabolismo , Citometria de Fluxo , Fluoresceína/metabolismo , Regulação Bacteriana da Expressão Gênica , Lectinas/genética , Polissacarídeos Bacterianos/genética , Aglutininas do Germe de Trigo/metabolismo
7.
Gynecol Endocrinol ; 35(2): 174-178, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30182781

RESUMO

Gestational diabetes mellitus (GDM) imparts a high risk of developing postpartum diabetes and is considered to be an early stage of type 2 diabetes mellitus (T2DM). In this study, a 75-g oral glucose tolerance test was performed on 472 women with GDM at 6-8 weeks after delivery. The clinical and metabolic characteristics were compared between the patients with normal glucose tolerance (NGT) and abnormal glucose metabolism (AGM). These data were then compared between pre-diabetic and diabetic patients. A total of 37.7% of the women with GDM continued to have abnormal glucose levels after delivery. Compared with the women who reverted to normal, HOMA-IR was significantly higher in AGM. A multiple stepwise regression analysis revealed that age, the postpartum body mass index (BMI), low density lipoprotein-cholesterol (LDL-C), 2 h glucose load plasma glucose (2 h PG), triglycerides (TG), hemoglobin A1c (HbA1c), 1 h glucose load plasma insulin (INS) level, and 2 h INS level were independent risk factors for the development of insulin resistance after delivery. This study has identified a high prevalence of AGM after GDM. Insulin resistance appears to be the major contributor. Any treatment to reduce the postpartum BMI and lipids level may be beneficial to decrease insulin resistance.


Assuntos
Diabetes Mellitus Tipo 2/metabolismo , Diabetes Gestacional/metabolismo , Intolerância à Glucose/metabolismo , Células Secretoras de Insulina/metabolismo , Período Pós-Parto/metabolismo , Estado Pré-Diabético/metabolismo , Adulto , Povo Asiático , Glicemia/metabolismo , Índice de Massa Corporal , China/epidemiologia , LDL-Colesterol/metabolismo , Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Gestacional/epidemiologia , Feminino , Intolerância à Glucose/epidemiologia , Hemoglobinas Glicadas/metabolismo , Humanos , Insulina/metabolismo , Resistência à Insulina , Estado Pré-Diabético/epidemiologia , Gravidez , Análise de Regressão , Fatores de Risco , Triglicerídeos/metabolismo
8.
Ecotoxicol Environ Saf ; 180: 130-138, 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31082576

RESUMO

Open-pit mining activities for minerals and metals have left an international legacy of highly polluted soils and degraded landscapes. Reforestation is usually supposed to restore soil fertility and ecosystem services, and therefore to remediate and recover polluted sites. However, our understanding of the effects of tree species and recovery time on the restoration of abiotic and biotic soil properties remains scarce. In this study, the effects of a series of restoration chronosequence (unrestored control, 10-year, 20-year, and natural forest) and plantation types (nitrogen-fixing broad-leaved Alnus nepalensis and coniferous Cupressus torulosa monocultures, as well as their mixed plantation) on soil physicochemical and biological properties were explored in a phosphate mine. Our results showed that soil quality index (SQI), which integrates important soil physical, chemical, and biological parameters including bulk density, soil organic carbon and microbial biomass, could provide valuable information about soil health. The average SQI values of 20-year plantations were 1.55 times of 10-year plantations, and the mixed plantation was 1.13 and 1.27 times of A. nepalensis and C. torulosa monoculture, respectively. Thus, recovery time, as well as plantation type, were the main determinants of the alterations in key soil conditions during the phosphate mining restoration. At the beginning restoration (10 years), A. nepalensis monoculture performed better than C. torulosa, providing an efficient restoration strategy for early revegetation. The mixed plantation of C. torulosa and A. nepalensis showed the higher moisture and soil organic carbon than did the monocultures, especially after 20 years of revegetation. Hence, our findings address a helpful guideline for selection of tree species and plantation practices, thereby aiding in long-term success of restoration.


Assuntos
Florestas , Mineração , Fosfatos/metabolismo , Solo , Árvores/metabolismo , Biodegradação Ambiental , Ecossistema , Monitoramento Ambiental , Microbiologia do Solo , Fatores de Tempo , Árvores/classificação
9.
Int J Gynecol Cancer ; 28(2): 385-393, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29266019

RESUMO

OBJECTIVES: The aim of this study was to investigate the different efficacies of various fertility-preserving therapies for grade 1 presumed stage IA endometrial cancer. METHODS: We searched the major online databases (PubMed, MEDLINE, Cochrane Library, Web of Science, and Ovid) and retrieved all the research on fertility-preserving treatment for young, grade 1 presumed stage IA endometrial adenocarcinoma patients since January 2000. We used the systemic evaluation of the Cochrane Collaboration to select the literature and merge the data we collected using R3.2.2 software (R Development Core Team, Auckland, New Zealand). By comparing the remission, recurrence, and pregnancy rates, we evaluated the efficiency of 3 existing fertility-preserving treatments indirectly: a) taking oral progestin only therapy, b) hysteroscopic resection followed by progestin therapy, and c) intrauterine progestin therapy: levonorgestrel-releasing intrauterine system combined with gonadotropin-releasing hormone agonist/progestin therapy. RESULTS: Twenty-eight studies met the selection criteria. A total of 619 cases were included in this study. The group that took oral progestin only (456 patients) achieved a complete remission rate (CRR), recurrence rate (ReR), and pregnancy rate (PregR) of 76.3%, (95% confidence interval [CI], 70.7%-81.1%); 30.7% (95% CI, 21.0%-42.4%); and 52.1% (95% CI, 41.2%-66.0%), respectively. The hysteroscopic resection followed by progestin therapy group (73 patients) achieved a CRR, ReR, and PregR of 95.3% (95% CI, 87.8%-100%); 14.1% (95% CI, 7.1%-26.1%); and 47.8% (95% CI, 33.0%-69.5%), respectively. The intrauterine progestin therapy group (90 patients) achieved a CRR, ReR, and PregR of 72.9% (95% CI, 60.4%-82.5%); 11.0% (95% CI, 5.1%-22.0%); and 56.0% (95% CI, 37.3%-73.1%), respectively. CONCLUSIONS: The existing results show that patients who received hysteroscopic resection followed by progestin therapy achieved the highest CRR. Patients who received oral progestin only might be more likely to recur and have more systemic adverse effects. Recent intrauterine progestin therapy such as levonorgestrel-releasing intrauterine system combined with gonadotropin-release hormone receptor agonist/progestin have a satisfactory PregR and low ReR rate. Considering the inherent limitations of the studies we included, further well-designed, randomized controlled trials are necessary to confirm and update this analysis.


Assuntos
Adenocarcinoma/patologia , Adenocarcinoma/terapia , Neoplasias do Endométrio/patologia , Neoplasias do Endométrio/terapia , Preservação da Fertilidade/métodos , Antineoplásicos Hormonais/uso terapêutico , Tratamento Conservador , Feminino , Humanos , Dispositivos Intrauterinos Medicados , Gradação de Tumores , Estadiamento de Neoplasias , Gravidez , Progestinas/uso terapêutico
10.
J Proteome Res ; 15(2): 628-37, 2016 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-26767403

RESUMO

Gestational diabetes mellitus (GDM) is considered as an early stage of type 2 diabetes mellitus. In this study, we compared demographic and clinical data between six GDM subjects and six normal glucose tolerance (NGT; healthy controls) subjects and found that homeostasis model of assessment for insulin resistance index (HOMA-IR) increased in GDM. Many previous studies demonstrated that omental adipose tissue dysfunction could induce insulin resistance. Thus, to investigate the cause of insulin resistance in GDM, we used label-free proteomics to identify differentially expressed proteins in omental adipose tissues from GDM and NGT subjects (data are available via ProteomeXchange with identifier PXD003095). A total of 3528 proteins were identified, including 66 significantly changed proteins. Adipocyte plasma membrane-associated protein (APMAP, a.k.a. C20orf3), one of the differentially expressed proteins, was down-regulated in GDM omental adipose tissues. Furthermore, mature 3T3-L1 adipocytes were used to simulate omental adipocytes. The inhibition of APMAP expression by RNAi impaired insulin signaling and activated NFκB signaling in these adipocytes. Our study revealed that the down-regulation of APMAP in omental adipose tissue may play an important role in insulin resistance in the pathophysiology of GDM.


Assuntos
Adipócitos/metabolismo , Tecido Adiposo/metabolismo , Diabetes Gestacional/metabolismo , Proteínas de Membrana/metabolismo , Proteoma/metabolismo , Proteômica/métodos , Células 3T3-L1 , Tecido Adiposo/fisiopatologia , Adulto , Animais , Western Blotting , Cromatografia Líquida , Diabetes Gestacional/genética , Diabetes Gestacional/fisiopatologia , Feminino , Humanos , Resistência à Insulina/genética , Resistência à Insulina/fisiologia , Proteínas de Membrana/genética , Camundongos , NF-kappa B/metabolismo , Omento/metabolismo , Gravidez , Proteoma/genética , Interferência de RNA , Transdução de Sinais , Espectrometria de Massas em Tandem
11.
Microbiology (Reading) ; 161(6): 1219-30, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25808172

RESUMO

Aspartate and glutamate are two key amino acids used in biosynthesis of many amino acids that play vital role in cellular metabolism. Aspartate aminotransferases (AspATs) are required for channelling nitrogen (N(2)) between Glu and Asp in all life forms. Biochemical and genetic characterization of AspATs have been lacking in N(2)-fixing cyanobacteria. In this report, five putative AspAT genes (alr1039, all2340, alr2765, all4327 and alr4853) were identified in the N(2)-fixing heterocystous cyanobacterium Anabaena sp. PCC 7120. Five recombinant C-terminal hexahistidine-tagged AspATs (AspAT-H(6)) were overexpressed in Escherichia coli and purified to homogeneity. Biochemical analysis demonstrated that these five putative AspATs have authentic AspAT activity in vitro using aspartate as an amino donor. However, the enzymic activities of the five AspATs differed in vitro. Alr4853-H(6) showed the highest AspAT activity, while the enzymic activity for the other four AspATs ranged from 6.5 to 53.7 % activity compared to Alr4853 (100 %). Genetic characterization of the five AspAT genes was also performed by inactivating each individual gene. All of the five AspAT knockout mutants exhibited reduced diazotrophic growth, and alr4853 was further identified to be a Fox gene (requiring fixed N(2) for growth in the presence of oxygen). Four out of five P(aspAT)-gfp transcriptional fusions were constitutively expressed in both diazotrophic and nitrate-dependent growth conditions. Quantitative reverse transcriptase PCR showed that alr4853 expression was increased by 2.3-fold after 24 h of N(2) deprivation. Taken together, these findings add to our understanding of the role of AspATs in N(2)-fixing within heterocystous cyanobacteria.


Assuntos
Anabaena/enzimologia , Aspartato Aminotransferases/genética , Aspartato Aminotransferases/metabolismo , Genes Bacterianos , Anabaena/genética , Aspartato Aminotransferases/isolamento & purificação , Clonagem Molecular , Escherichia coli/genética , Escherichia coli/metabolismo , Expressão Gênica , Perfilação da Expressão Gênica , Regulação Bacteriana da Expressão Gênica , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/metabolismo
12.
Appl Microbiol Biotechnol ; 99(4): 1779-93, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25434810

RESUMO

Determining spatiotemporal gene expression and analyzing knockout mutant phenotypes have become powerful tools in elucidating the function of genes; however, genetic approaches for simultaneously inactivating a gene and monitoring its expression have not been reported in the literature. In this study, we designed a dual-functional gene knockout vector pZR606 that contains a multiple cloning site (MCS) for inserting the internal fragment of a target gene, with a gfp gene as its transcriptional marker located immediately downstream of the MCS. By using this gene knockout system, we inactivated ava_2679 from Anabaena variabilis ATCC 29413, as well as all2508, alr2887, alr3608, and all4388 from Anabaena sp. strain PCC 7120. The ava_2679 knockout mutant fails to grow diazotrophically. Morphological analysis of ava_2679 knockout mutant after nitrogen step-down revealed defective junctions between heterocysts and adjacent vegetative cells, and the heterocyst was 1.53-fold longer compared to wild-type heterocysts. The alr2887, all4388, and alr3608 mutant colonies turned yellow and showed lack of protracted growth when deprived of fixed nitrogen, consistent with the previous reports that alr2887, all4388, and alr3608 are Fox genes. The all2508 encodes a GTP-binding elongation factor (EF4/LepA), and its knockout mutant exhibited reduced diazotrophic growth. The heterocyst development of all2508 knockout was significantly delayed, and only about 4.0 % of vegetative cells differentiated to heterocysts after nitrogen deprivation for 72 h, decreased 49.6 % compared to wild-type. Thus, we discovered that All2508 may regulate heterocyst development spatiotemporally. Concurrently, the GFP reporter revealed that all five target gene expressions were up-regulated in response to nitrogen deprivation. We demonstrated that the pZR606-based specific gene knockout approach worked effectively for the five selected genes, including four previously identified Fox genes or Fox gene homolog, and a previously unknown function of gene all2508. Thus, gene expression and phenotypic analysis of mutants can be achieved simultaneously by targeted gene inactivation using the pZR606-based system. This combined approach for targeted gene inactivation and its promoter reporting with GFP may be broadly applicable to the study of gene function in other prokaryotic organisms.


Assuntos
Anabaena variabilis/crescimento & desenvolvimento , Anabaena variabilis/genética , Regulação Bacteriana da Expressão Gênica , Técnicas de Inativação de Genes/métodos , Inativação Gênica , Genes Reporter , Regiões Promotoras Genéticas , Anabaena variabilis/citologia , Anabaena variabilis/fisiologia , Proteínas de Fluorescência Verde/análise , Proteínas de Fluorescência Verde/genética , Dados de Sequência Molecular , Fixação de Nitrogênio , Análise de Sequência de DNA
13.
Mediators Inflamm ; 2015: 272313, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25653476

RESUMO

Obesity-induced endoplasmic reticulum (ER) stress and inflammation lead to adipocytes dysfunction. Autophagy helps to adapt to cellular stress and involves in regulating innate inflammatory response. In present study, we examined the activity of rapamycin, a mTOR kinase inhibitor, against endoplasmic reticulum stress and inflammation in adipocytes. An in vitro model was used in which 3T3-L1 adipocytes were preloaded with palmitate (PA) to generate artificial hypertrophy mature adipocytes. Elevated autophagy flux and increased number of autophagosomes were observed in response to PA and rapamycin treatment. Rapamycin attenuated PA-induced PERK and IRE1-associated UPR pathways, evidenced by decreased protein levels of eIF2α phosphorylation, ATF4, CHOP, and JNK phosphorylation. Inhibiting autophagy with chloroquine (CQ) exacerbated these ER stress markers, indicating the role of autophagy in ameliorating ER stress. In addition, cotreatment of CQ abolished the anti-ER stress effects of rapamycin, which confirms the effect of rapamycin on ERs is autophagy-dependent. Furthermore, rapamycin decreased PA-induced nuclear translocation of NFκB P65 subunit, thereby NFκB-dependent inflammatory cytokines MCP-1 and IL-6 expression and secretion. In conclusion, rapamycin attenuated PA-induced ER stress/NFκB pathways to counterbalance adipocytes stress and inflammation. The beneficial of rapamycin in this context partly depends on autophagy. Stimulating autophagy may become a way to attenuate adipocytes dysfunction.


Assuntos
Adipócitos/efeitos dos fármacos , Adipócitos/metabolismo , Autofagia/efeitos dos fármacos , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Palmitatos/farmacologia , Sirolimo/farmacologia , Células 3T3-L1 , Adipócitos/ultraestrutura , Animais , Western Blotting , Quimiocina CCL2/metabolismo , Cloroquina/farmacologia , Ensaio de Imunoadsorção Enzimática , Imunofluorescência , Interleucina-6/metabolismo , Camundongos , Microscopia Eletrônica , Reação em Cadeia da Polimerase em Tempo Real
14.
Appl Microbiol Biotechnol ; 98(23): 9869-77, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25301585

RESUMO

Genetically engineered cyanobacteria offer a shortcut to convert CO2 and H2O directly into biofuels and high value chemicals for societal benefits. Farnesene, a long-chained hydrocarbon (C15H24), has many applications in lubricants, cosmetics, fragrances, and biofuels. However, a method for the sustainable, photosynthetic production of farnesene has been lacking. Here, we report the photosynthetic production of farnesene by the filamentous cyanobacterium Anabaena sp. PCC 7120 using only CO2, mineralized water, and light. A codon-optimized farnesene synthase gene was chemically synthesized and then expressed in the cyanobacterium, enabling it to synthesize farnesene through its endogenous non-mevalonate (MEP) pathway. Farnesene excreted from the engineered cyanobacterium volatilized into the flask head space and was recovered by adsorption in a resin column. The maximum photosynthetic productivity of farnesene was 69.1 ± 1.8 µg·L(-1)·O.D.(-1)·d(-1). Compared to the wild type, the farnesene-producing cyanobacterium also exhibited a 60 % higher PSII activity under high light, suggesting increased farnesene productivity in such conditions. We envision genetically engineered cyanobacteria as a bio-solar factory for photosynthetic production of a wide range of biofuels and commodity chemicals.


Assuntos
Anabaena/genética , Anabaena/metabolismo , Dióxido de Carbono/metabolismo , Luz , Engenharia Metabólica , Sesquiterpenos/metabolismo , Água/metabolismo , Biocombustíveis , Fotossíntese
15.
Biomimetics (Basel) ; 9(6)2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38921253

RESUMO

The sophisticated, elegant protein-polymers designed by nature can serve as inspiration to redesign and biomanufacture protein-based materials using synthetic biology. Historically, petro-based polymeric materials have dominated industrial activities, consequently transforming our way of living. While this benefits humans, the fabrication and disposal of these materials causes environmental sustainability challenges. Fortunately, protein-based biopolymers can compete with and potentially surpass the performance of petro-based polymers because they can be biologically produced and degraded in an environmentally friendly fashion. This paper reviews four groups of protein-based polymers, including fibrous proteins (collagen, silk fibroin, fibrillin, and keratin), elastomeric proteins (elastin, resilin, and wheat glutenin), adhesive/matrix proteins (spongin and conchiolin), and cyanophycin. We discuss the connection between protein sequence, structure, function, and biomimetic applications. Protein engineering techniques, such as directed evolution and rational design, can be used to improve the functionality of natural protein-based materials. For example, the inclusion of specific protein domains, particularly those observed in structural proteins, such as silk and collagen, enables the creation of novel biomimetic materials with exceptional mechanical properties and adaptability. This review also discusses recent advancements in the production and application of new protein-based materials through the approach of synthetic biology combined biomimetics, providing insight for future research and development of cutting-edge bio-inspired products. Protein-based polymers that utilize nature's designs as a base, then modified by advancements at the intersection of biology and engineering, may provide mankind with more sustainable products.

16.
J Colloid Interface Sci ; 656: 320-331, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-37995402

RESUMO

Ferroptosis-mediated tumor treatment is constrained by the absence of single-component, activatable multifunctional inducers. Given this, a topological synthesis strategy is employed to develop an efficient bismuth-based semiconductor nano-photocatalyst (Bi2O3:S) for tumor ferroptosis therapy. Photo-excited electrons can participate in the reduction reaction to produce harmful reactive oxygen species (ROS) when exposed to near-infrared light. Meanwhile, photo-excited holes can contribute to the oxidation reaction to utilize extra glutathione (GSH) in tumors. In the acidic tumor microenvironment, bismuth ions generated from Bi2O3:S may further cooperate with GSH to amplify oxidative stress damage and achieve biodegradation. Both promote ferroptosis by downregulating glutathione peroxidase 4 (GPX4) expression. Besides, sulfur doping optimizes its near-infrared light-induced photothermal conversion efficiency, benefiting its therapeutic effect. Thus, bismuth ions and holes synergistically drive photo-activable ferroptosis in this nanoplatform, opening up new avenues for tumor therapy.


Assuntos
Ferroptose , Neoplasias , Fotoquimioterapia , Humanos , Bismuto , Glutationa , Espécies Reativas de Oxigênio , Íons , Neoplasias/terapia , Linhagem Celular Tumoral , Fototerapia , Microambiente Tumoral
17.
Sci Bull (Beijing) ; 69(12): 1920-1935, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38423871

RESUMO

Diabetic retinopathy (DR) is the leading cause of blindness among the working-age population. Although controlling blood glucose levels effectively reduces the incidence and development of DR to less than 50%, there are currently no diagnostic biomarkers or effective treatments for DR development in glucose-well-controlled diabetic patients (GW-DR). In this study, we established a prospective GW-DR cohort by strictly adhering to glycemic control guidelines and maintaining regular retinal examinations over a median 2-year follow-up period. The discovery cohort encompassed 71 individuals selected from a pool of 292 recruited diabetic patients at baseline, all of whom consistently maintained hemoglobin A1c (HbA1c) levels below 7% without experiencing hypoglycemia. Within this cohort of 71 individuals, 21 subsequently experienced new-onset GW-DR, resulting in an incidence rate of 29.6%. In the validation cohort, we also observed a significant GW-DR incidence rate of 17.9%. Employing targeted metabolomics, we investigated the metabolic characteristics of serum in GW-DR, revealing a significant association between lower levels of ethanolamine and GW-DR risk. This association was corroborated in the validation cohort, exhibiting superior diagnostic performance in distinguishing GW-DR from diabetes compared to the conventional risk factor HbA1c, with AUCs of 0.954 versus 0.506 and 0.906 versus 0.521 in the discovery and validation cohorts, respectively. Furthermore, in a streptozotocin (STZ)-induced diabetic rat model, ethanolamine attenuated diabetic retinal inflammation, accompanied by suppression of microglial diacylglycerol (DAG)-dependent protein kinase C (PKC) pathway activation. In conclusion, we propose that ethanolamine is a potential biomarker and represents a viable biomarker-based therapeutic option for GW-DR.


Assuntos
Biomarcadores , Retinopatia Diabética , Etanolamina , Humanos , Retinopatia Diabética/sangue , Retinopatia Diabética/diagnóstico , Retinopatia Diabética/epidemiologia , Biomarcadores/sangue , Animais , Masculino , Feminino , Pessoa de Meia-Idade , Hemoglobinas Glicadas/análise , Hemoglobinas Glicadas/metabolismo , Ratos , Glicemia/metabolismo , Glicemia/análise , Estudos Prospectivos , Diabetes Mellitus Experimental/sangue , Idoso , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/complicações , Controle Glicêmico/métodos
18.
J Diabetes ; 16(1): e13466, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37670495

RESUMO

OBJECTIVE: This study investigated the association of economic status with metabolic index control in type 2 diabetes mellitus (T2DM) patients. METHODS: In total, 37 454 T2DM patients from 10 National Metabolic Management Centers in China were recruited and categorized into two groups: a high-gross domestic product (GDP) group (n = 23 993) and a low-GDP group (n = 13 461). Sociodemographic characteristics, medical histories, and lifestyle factors were recorded. Logistic regression and interaction analysis were performed to evaluate the association of economic status and healthy lifestyle with metabolic control. RESULTS: Compared to the low-GDP group, there were fewer patients with glycated hemoglobin (HbA1c) levels ≥7% in the high-GDP group. Fewer patients with a high GDP had an abnormal metabolic state (HbA1c ≥ 7%, blood pressure [BP] ≥130/80 mm Hg, total cholesterol [TCH] ≥4.5 mmol/L or body mass index [BMI] ≥24 kg/m2 ). The risks of developing HbA1c ≥ 7% (odds ratios [OR] = 0.545 [95% CI: 0.515-0.577], p < .001), BP ≥ 130/80 mm Hg (OR = 0.808 [95% CI: 0.770-0.849], p < .001), BMI ≥ 24 kg/m2 (OR = 0.840 [95% CI: 0.799-0.884], p < .001), and an abnormal metabolic state (OR = 0.533 [95% CI: 0.444-0.636], p < .001) were significantly lower in the high-GDP group even after adjustment for confounding factors. Younger participants; those with a family history of diabetes, normal weight, and a physical activity level up to standard; and those who did not drink alcohol in the high-GDP group were predisposed to better glycemic levels. CONCLUSIONS: T2DM patients in economically developed regions had better metabolic control, especially glycemic control. A healthy lifestyle had an additive effect on achieving glycemic goals, even among high-GDP patients.


Assuntos
Diabetes Mellitus Tipo 2 , Humanos , Hemoglobinas Glicadas , Glicemia/metabolismo , Status Econômico , China/epidemiologia
19.
J Bacteriol ; 195(12): 2793-806, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23585539

RESUMO

Intramembrane proteases regulate diverse processes by cleaving substrates within a transmembrane segment or near the membrane surface. Bacillus subtilis SpoIVFB is an intramembrane metalloprotease that cleaves Pro-σ(K) during sporulation. To elucidate features of Pro-σ(K) important for cleavage by SpoIVFB, coexpression of the two proteins in Escherichia coli was used along with cell fractionation. In the absence of SpoIVFB, a portion of the Pro-σ(K) was peripherally membrane associated. This portion was not observed in the presence of SpoIVFB, suggesting that it serves as the substrate. Deletion of Pro-σ(K) residues 2 to 8, addition of residues at its N terminus, or certain single-residue substitutions near the cleavage site impaired cleavage. Certain multiresidue substitutions near the cleavage site changed the position of cleavage, revealing preferences for a small residue preceding the cleavage site N-terminally (i.e., at the P1 position) and a hydrophobic residue at the second position following the cleavage site C-terminally (i.e., P2'). These features appear to be conserved among Pro-σ(K) orthologs. SpoIVFB did not tolerate an aromatic residue at P1 or P2' of Pro-σ(K). A Lys residue at P3' of Pro-σ(K) could not be replaced with Ala unless a Lys was provided farther C-terminally (e.g., at P9'). α-Helix-destabilizing residues near the cleavage site were not crucial for SpoIVFB to cleave Pro-σ(K). The preferences and tolerances of SpoIVFB are somewhat different from those of other intramembrane metalloproteases, perhaps reflecting differences in the interaction of the substrate with the membrane and the enzyme.


Assuntos
Bacillus subtilis/enzimologia , Bacillus subtilis/metabolismo , Proteínas de Bactérias/metabolismo , Endopeptidases/metabolismo , Proteínas de Membrana/metabolismo , Precursores de Proteínas/metabolismo , Fatores de Transcrição/metabolismo , Bacillus subtilis/química , Bacillus subtilis/genética , Membrana Celular/química , Análise Mutacional de DNA , Escherichia coli/genética , Escherichia coli/metabolismo , Expressão Gênica , Técnicas de Inativação de Genes , Hidrólise , Insulina Lispro , Modelos Moleculares , Precursores de Proteínas/genética , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Fatores de Transcrição/genética
20.
Clin Hemorheol Microcirc ; 83(2): 129-136, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36213990

RESUMO

OBJECTIVE: To establish a nomogram for predicting cervical lymph node metastasis (CLNM) based on the preoperative conventional ultrasound (US) and shear wave velocity (SWV) features of papillary thyroid carcinoma (PTC). METHODS: A total of 101 patients with pathologically confirmed thyroid nodules were enrolled. These patients were divided into the CLNM-positive (n = 40) and CLNM-negative groups (n = 61). All patients underwent the preoperative conventional US and shear wave elastography (SWE) evaluation, and the US parameters and SWV data were collected. The association between SWV ratio and CLNM was compared to assess the diagnostic efficacy of SWV ratio alone as opposed to SWV ratio in combination with the conventional US for predicting CLNM. RESULTS: There were significant differences in shape, microcalcification, capsule contact, SWV mean, and SWV ratio between the CLNM-positive and CLNM-negative groups (P < 0.05). Logistic regression analysis showed that taller-than-wide shape, microcalcification, capsule contact, and SWV ratio > 1.3 were risk factors for CLNM; Logistic(P)=-6.93 + 1.647 * (microcalcification)+1.138 * (taller-than-wide-shape)+1.612 * (capsule contact)+2.933 * (SWV ratio > 1.3). The area under the curve (AUC) of the receiver operating characteristic (ROC) of the model for CLNM prediction was 0.87, with 81.19% accuracy, 77.5% sensitivity, and 85.25% specificity. CONCLUSION: The nomogram based on conventional US imaging in combination with SWV ratio has the potential for preoperative CLNM risk assessment. This nomogram serves as a useful clinical tool for active surveillance and treatment decisions.


Assuntos
Calcinose , Neoplasias da Glândula Tireoide , Humanos , Câncer Papilífero da Tireoide/patologia , Neoplasias da Glândula Tireoide/patologia , Nomogramas , Metástase Linfática/patologia , Linfonodos/patologia , Fatores de Risco , Calcinose/patologia , Estudos Retrospectivos
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