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1.
Am J Pathol ; 193(7): 899-912, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37068638

RESUMO

The accuracy and timeliness of the pathologic diagnosis of soft tissue tumors (STTs) critically affect treatment decision and patient prognosis. Thus, it is crucial to make a preliminary judgement on whether the tumor is benign or malignant with hematoxylin and eosin-stained images. A deep learning-based system, Soft Tissue Tumor Box (STT-BOX), is presented herein, with only hematoxylin and eosin images for malignant STT identification from benign STTs with histopathologic similarity. STT-BOX assumed gastrointestinal stromal tumor as a baseline for malignant STT evaluation, and distinguished gastrointestinal stromal tumor from leiomyoma and schwannoma with 100% area under the curve in patients from three hospitals, which achieved higher accuracy than the interpretation of experienced pathologists. Particularly, this system performed well on six common types of malignant STTs from The Cancer Genome Atlas data set, accurately highlighting the malignant mass lesion. STT-BOX was able to distinguish ovarian malignant sex-cord stromal tumors without any fine-tuning. This study included mesenchymal tumors that originated from the digestive system, bone and soft tissues, and reproductive system, where the high accuracy of migration verification may reveal the morphologic similarity of the nine types of malignant tumors. Further evaluation in a pan-STT setting would be potential and prospective, obviating the overuse of immunohistochemistry and molecular tests, and providing a practical basis for clinical treatment selection in a timely manner.


Assuntos
Aprendizado Profundo , Tumores do Estroma Gastrointestinal , Neoplasias Ovarianas , Neoplasias de Tecidos Moles , Feminino , Humanos , Tumores do Estroma Gastrointestinal/diagnóstico , Tumores do Estroma Gastrointestinal/patologia , Amarelo de Eosina-(YS) , Hematoxilina , Estudos Prospectivos , Neoplasias de Tecidos Moles/diagnóstico
2.
BMC Cancer ; 23(1): 103, 2023 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-36717797

RESUMO

BACKGROUND: Real-world data of Palbociclib are insufficient in China. This study aimed to investigate the treatment pattern and real-world outcomes in hormone receptor positive and human epidermal growth factor 2 receptor negative (HR+/HER2-) metastatic breast cancer (MBC) patients treated with Palbociclib in the northwest of China. METHODS: HR+/HER2- MBC patients who received Palbociclib in 8 centers from July 2017 to September 2019 were retrospectively included in this study. Real-world objective response rate (ORR), progression-free survival (PFS) and safety profiles were analyzed. The survival curves were plotted by the Kaplan-Meier method to analyze PFS, which was verified by the log-rank test. RESULTS: In total, 211 women were eligible for the analysis. A total of 85 patients (40.3%), 78 (37.0%), and 48 (22.7%) received Palbociclib in the first-, second-, third- or later-line setting, respectively. 46 patients achieved partial response and 145 patients experienced stable disease, with an ORR of 21.8% and a disease control rate of 90.5%. Following a median follow-up period of 14.2 months, the median PFS was 12.2 months (95% confidence interval, 10.1-14.3 m), and the median overall survival was not reached. Early Palbociclib initiation, sensitivity or acquired resistance to endocrine therapy, estrogen receptor and progesterone receptor double positivity, less than 3 metastatic sites, without visceral metastasis, bone metastasis only, without prior chemotherapy or endocrine therapy were associated with a prolonged PFS in MBC (All P < 0.05). The most common grade 3 or 4 adverse events (AE) was neutropenia (36.5%), and the most common nonhematologic AE was fatigue (10.9%). No patient experienced AE leading to treatment discontinuation. CONCLUSION: Palbociclib plus endocrine therapy exhibited favorable effectiveness and manageable toxicities in the real-world setting, supporting their use in Chinese patients with HR+/HER2 - MBC.


Assuntos
Neoplasias da Mama , Feminino , Humanos , Protocolos de Quimioterapia Combinada Antineoplásica , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Receptor ErbB-2/metabolismo , Estudos Retrospectivos
3.
Molecules ; 27(19)2022 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-36235164

RESUMO

An effective method for separating and purifying critical saponins (polyphyllin II and polyphyllin VII) from a Paris polyphylla var. yunnanensis extract was developed in this study which was environmentally friendly and economical. Static adsorption kinetics, thermodynamics, and the dynamic adsorption-desorption of macroporous resins were investigated, and then the conditions of purification and separation were optimized by fitting with an adsorption thermodynamics equation and a kinetic equation. Effective NKA-9 resin from seven macroporous resins was screened out to separate and purify the two saponins. The static adsorption and dynamic adsorption were chemical and physical adsorption dual-processes on the NKA-9 resin. Under the optimum parameters, the contents of polyphyllin II and polyphyllin VII in the product were 17.3-fold and 28.6-fold those in plant extracts, respectively. The total yields of the two saponins were 93.16%. This research thus provides a theoretical foundation for the large-scale industrial production of the natural drugs polyphyllin II and polyphyllin VII.


Assuntos
Liliaceae , Melanthiaceae , Saponinas , Adsorção , Liliaceae/química , Melanthiaceae/química , Extratos Vegetais , Resinas Vegetais , Saponinas/química
4.
Br J Cancer ; 125(3): 351-357, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33953345

RESUMO

BACKGROUND: Oesophageal cancer (EC) ranks high in both morbidity and mortality. A non-invasive and high-sensitivity diagnostic approach is necessary to improve the prognosis of EC patients. METHODS: A total of 525 serum samples were subjected to lipidomic analysis. We combined serum lipidomics and machine-learning algorithms to select important metabolite features for the detection of oesophageal squamous cell carcinoma (ESCC), the major subtype of EC in developing countries. A diagnostic model using a panel of selected features was developed and evaluated. Integrative analyses of tissue transcriptome and serum lipidome were conducted to reveal the underlying mechanism of lipid dysregulation. RESULTS: Our optimised diagnostic model with a panel of 12 lipid biomarkers together with age and gender reaches a sensitivity of 90.7%, 91.3% and 90.7% and an area under receiver-operating characteristic curve of 0.958, 0.966 and 0.818 in detecting ESCC for the training cohort, validation cohort and independent validation cohort, respectively. Integrative analysis revealed matched variation trend of genes encoding key enzymes in lipid metabolism. CONCLUSIONS: We have identified a panel of 12 lipid biomarkers for diagnostic modelling and potential mechanisms of lipid dysregulation in the serum of ESCC patients. This is a reliable, rapid and non-invasive tumour-diagnostic approach for clinical application.


Assuntos
Biomarcadores Tumorais/sangue , Biomarcadores Tumorais/genética , Neoplasias Esofágicas/diagnóstico , Carcinoma de Células Escamosas do Esôfago/diagnóstico , Perfilação da Expressão Gênica/métodos , Lipidômica/métodos , Idoso , Área Sob a Curva , Estudos de Casos e Controles , Detecção Precoce de Câncer , Neoplasias Esofágicas/sangue , Neoplasias Esofágicas/metabolismo , Carcinoma de Células Escamosas do Esôfago/sangue , Carcinoma de Células Escamosas do Esôfago/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Aprendizado de Máquina , Masculino , Pessoa de Meia-Idade , Prognóstico , Curva ROC , Sensibilidade e Especificidade , Máquina de Vetores de Suporte
5.
Microb Pathog ; 160: 105162, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34461245

RESUMO

Heteroresistance is a poorly understood mechanism of resistance which refers to a phenomenon where there are different subpopulations of seemingly isogenic bacteria which exhibit a range of susceptibilities to a particular antibiotic. In the current study, we identified a multidrug-resistant, carbapenemase-positive K. pneumoniae strain SWMUF35 which was classified as susceptible to amikacin and resistant to meropenem by clinical diagnostics yet harbored different subpopulations of phenotypically resistant cells, and has the ability to form biofilm. Population analysis profile (PAP) indicated that SWMUF35 showed heteroresistance towards amikacin and meropenem which was considered as co-heteroresistant K. pneumoniae strain. In vitro experiments such as dual PAP, dual Times-killing assays and checkerboard assay showed that antibiotic combination therapy (amikacin combined with meropenem) can effectively combat SWMUF35. Importantly, using an in vivo mouse model of peritonitis, we found that amikacin or meropenem monotherapy was unable to rescue mice infected with SWMUF35. Antibiotic combination therapy could be a rational strategy to use clinically approved antibiotics when monotherapy would fail. Furthermore, our data warn that antibiotic susceptibility testing results may be unreliable due to undetected heteroresistance which can lead to treatment failure and the detection of this phenotype is a prerequisite for a proper choice of antibiotic to support a successful treatment outcome.


Assuntos
Amicacina , Carbapenêmicos , Animais , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Modelos Animais de Doenças , Klebsiella pneumoniae , Meropeném/farmacologia , Camundongos , Testes de Sensibilidade Microbiana , Falha de Tratamento
6.
Fungal Genet Biol ; 134: 103278, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31610212

RESUMO

Transmembrane proteins as sensors encoded by fungal genes activate specific intracellular signal pathways in response to stress cues to help the fungus survive in a changing environment. To better understand the role of the cell wall integrity (CWI) pathway in the entomopathogenic fungus Metarhizium rileyi, an ortholog encoding the transmembrane protein Mid2, MrMid2, was identified and characterized functionally. Transcriptional analysis indicated that MrMid2 was involved in dimorphic transition, conidiation, and microsclerotium formation. After a targeted deletion of MrMid2, all three traits were impaired. Compared with the wild-type strain, the △MrMid2 mutants were hypersensitive to thermal stress, and cell wall and oxidative stress. Insect bioassays revealed that △MrMid2 mutants had decreased virulence levels following topical (22.5%) and injection bioassays (38.7%). Furthermore, transcription analysis showed that other genes of the CWI pathway, with the exception of another major sensor protein encoding gene, MrWsc1, were down-regulated in △MrMid2 mutants. These results suggest that MrMid2 plays important roles in dimorphic transition, conidiation, the stress response, virulence, and microsclerotium development in M. rileyi.


Assuntos
Parede Celular/metabolismo , Proteínas Fúngicas/genética , Genes Fúngicos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Glicoproteínas de Membrana/genética , Metarhizium/genética , Metarhizium/patogenicidade , Estresse Oxidativo/genética , Esporos Fúngicos/crescimento & desenvolvimento , Animais , Deleção de Genes , Regulação Fúngica da Expressão Gênica , Hifas/crescimento & desenvolvimento , Plasmídeos/genética , Transdução de Sinais/genética , Spodoptera/microbiologia , Transcriptoma , Virulência
7.
Am J Pathol ; 189(8): 1495-1500, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31345466

RESUMO

Skeletal tissue development and regeneration in mammals are intricate, multistep, and highly regulated processes. Various signaling pathways have been implicated in the regulation of these processes, including Notch. Notch signaling is a highly conserved, intercellular signaling pathway that regulates cell proliferation and differentiation, determines cell fate decision, and participates in cellular process in embryonic and adult tissue. Here, we review recent data showing the regulation of Notch signaling in osteogenesis, osteoclastogenesis, and angiogenesis. These processes are cell-context-dependent via direct or indirect mechanisms. Furthermore, Notch signaling may be highly beneficial for efficient coupling of osteogenesis and angiogenesis for tissue engineering and skeletal repair, which is critical to develop clinically therapeutic options.


Assuntos
Diferenciação Celular/fisiologia , Proliferação de Células/fisiologia , Neovascularização Fisiológica/fisiologia , Osteogênese/fisiologia , Receptores Notch/metabolismo , Transdução de Sinais/fisiologia , Animais , Humanos
8.
Appl Environ Microbiol ; 86(8)2020 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-32005738

RESUMO

APSES-type transcription factors (TFs) have analogous and diverse functions in the regulation of fungal morphogenesis processes. However, little is known about these functions in microsclerotium formation. In this study, we characterized two orthologous APSES genes (MrStuA and MrXbp) in the entomopathogenic fungus Metarhizium rileyi Deletion of either MrStuA or MrXbp impaired dimorphic transition, conidiation, fungal virulence, and microsclerotium formation. Compared with the wild-type strain, ΔMrStuA and ΔMrXbp mutants were hypersensitive to thermal and oxidative stress. Furthermore, transcriptome sequencing analysis revealed that MrStuA and MrXbp independently regulate their own distinctive subsets of signaling pathways during dimorphic transition and microsclerotium formation, but they also show an overlapping regulation of genes during these two distinct morphogenesis processes. These results provide a global insight into vital roles of MrStuA and MrXbp in M. rileyi and aid in dissection of the interacting regulatory mechanisms of dimorphism transition and microsclerotium development.IMPORTANCE Transcription factors (TFs) are core components of the signaling pathway and play an important role in transcriptional regulation of gene expression during fungal morphogenesis processes. A prevailing theory suggests an interplay between different TFs regulating microsclerotial differentiation; however, the persisting issue remains that these interplay mechanisms are not clear. Here, we analyzed two members of the APSES-type TFs in Metarhizium rileyi using a gene deletion strategy and transcriptome analysis. Mutants were significantly impaired in microsclerotium formation and dimorphic transition. Transcriptome analysis provided evidence for interacting regulatory mechanisms by the two TFs in microsclerotium formation and dimorphic transition. Furthermore, we investigated their overlapping roles in mediating the expression of genes required for different fungal morphogenesis processes. Characterization of TFs in this study will aid in dissecting the interplay between regulatory mechanisms in fungal morphogenesis processes.


Assuntos
Proteínas Fúngicas/genética , Metarhizium/genética , Fatores de Transcrição/genética , Proteínas Fúngicas/metabolismo , Metarhizium/crescimento & desenvolvimento , Morfogênese/genética , Fatores de Transcrição/metabolismo
9.
Pestic Biochem Physiol ; 165: 104506, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32359553

RESUMO

Monochoria vaginalis and M. korsakowii are allotetraploid noxious weeds in rice cultivation. Occurrences of resistance to acetolactate synthase (ALS)-inhibiting herbicides have been reported in these weeds in Japan since the 1990s. The existence of multiple copies of ALS genes in both species has hindered and complicated the detailed study of molecular mechanisms in them. To determine the copy number and full-length of ALS genes in both species, we first amplified partial sequences of ALS genes and separated them by cloning. Five and three distinct sequences were identified in M. vaginalis and M. korsakowii, respectively. RACE and TAIL PCR successfully isolated full-length ALS genes, revealing that one copy of ALS genes in both species is a pseudogene formed by a frameshift mutation. Interestingly, one of the four putative functional ALS genes in M. vaginalis contains an intron in the 3'-untranslated region. Amplification and sequencing of the full-length ALS genes in sensitive and suspected resistant lines revealed a non-synonymous point mutation at codon Pro197, resulting in amino acid substitutions (Leu, Ser, or Ala) well known to endow ALS inhibitor resistance. Importantly, codon Pro197 of the M. korsakowii pseudogene encodes leucine (Leu) both in resistant and sensitive plants, which is also known to confer ALS inhibitor resistance when ALS genes are functional. Dose responses to imazosulfuron of the lines analyzed for ALS genes were in agreement with the existence of the mutations. These results suggest that some caution is needed when diagnosing molecular resistance in M. korsakowii. The information of copy number and full-length sequences will help diagnose ALS resistance and make a basis for the study of the evolution of ALS resistance in Monochoria spp.


Assuntos
Acetolactato Sintase , Herbicidas , Resistência a Herbicidas , Humanos , Japão , Mutação , Plantas Daninhas , Tetraploidia
10.
BMC Microbiol ; 19(1): 50, 2019 02 26.
Artigo em Inglês | MEDLINE | ID: mdl-30808281

RESUMO

BACKGROUND: Drought and its resulting oxidative damage are the major yield limiting factors for crops in arid and semi-arid regions. Recent studies have found that endophytic fungi coexisting in plants can alleviate biotic or abiotic damage to plant growth and development. In order to screen for the endophytes associated with drought stress, 12 strains of endophytic fungi with high antioxidant activity isolated from riparian plants Myricaria laxiflora were evaluated for their effects in rice by the crude extracts. RESULTS: Of the 12 endophytic fungi, Aspergillus fumigatus SG-17 functioned most effectively, with the crude extract exhibiting relatively higher antioxidant capacity both in vivo and in vitro. The subsequent MS and NMR analysis showed that the primary substance responsible for the antioxidant activity in the extract was (Z)-N-(4-hydroxystyryl) formamide (NFA), an analogue of coumarin. Enzyme activity assay in nerve cells SH-SY5Y showed that NFA could maintain the membrane integrity and regulate the antioxidase activity under oxidative stress. In rice suffering drought stress, NFA effectively alleviated the harm by regulating the contents of NADPH oxidases, antioxidants and heat shock proteins, all of which are closely related with the reactive oxygen species pathway. CONCLUSION: These findings indicated that some endophytes from plants often subjected to flooding and oxidative stress could enhance drought resistance by producing compounds such as NFA to regulate the oxidative pathway.


Assuntos
Antioxidantes/farmacologia , Aspergillus fumigatus/química , Secas , Formamidas/farmacologia , Oryza/efeitos dos fármacos , Antioxidantes/isolamento & purificação , Cumarínicos/isolamento & purificação , Cumarínicos/farmacologia , Endófitos/química , Inundações , Formamidas/isolamento & purificação , Estresse Oxidativo/efeitos dos fármacos , Raízes de Plantas/microbiologia , Salinidade , Estresse Fisiológico/efeitos dos fármacos , Tamaricaceae/microbiologia
11.
Microb Pathog ; 128: 1-6, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30576714

RESUMO

Carbapenem-resistant Enterobacteriaceae strains as a new serious threat for the public health have been increasingly reported worldwide. In this study, one multi-resistant Escherichia coli strain ZSH6 which co-carried blaKPC-2, blaNDM-5 and blaCTX-M, was isolated from human blood sample. By using plasmid conjugation experiments, ZSH6 was found to harbor three plasmids carrying the blaNDM-5 gene, the blaKPC-2 and blaCTX-M gene, respectively. Whole-genome sequencing of ZSH6 yielded 122 scaffolds of chromosomal DNA and three circular plasmids including pZSH6-blaKPC-2 (46,319 bp), pZSH6-blaNDM-5 (46,161bp) and pZSH6-blaCTX-M (184,723). The isolate was classified to Sequence Type 2 and to the O89: H10 serotype. The results of genome analyses revealed that ZSH6 carried three virulence factors (capU, gad and iss) and twenty resistance genes [blaKPC-2blaNDM-5, blaCTX-M-3, blaCTX-M-65, blaTEM-1, floR, tet(A), tet(B), dfrA17, aadA5, sul1, mdf(A), mph(A), erm(B), aph(3')-Ia, aph(3')-Ib, aph(4)-Ia, aph(6)-Id, aac(3)-Iva, aac(3)-IId]. Therefore, the co-existence of such a large number of resistance genes in multiple plasmids making ZSH6 highly resistant to almost all kinds of commonly used antibiotics, and brings a serious challenge for resistance control and clinical treatment of infections caused by this bacterium.


Assuntos
Farmacorresistência Bacteriana Múltipla/genética , Proteínas de Escherichia coli/genética , Escherichia coli/genética , Plasmídeos/genética , Sorogrupo , beta-Lactamases/genética , Idoso de 80 Anos ou mais , Antibacterianos/farmacologia , Enterobacteriáceas Resistentes a Carbapenêmicos , China , Escherichia coli/classificação , Escherichia coli/efeitos dos fármacos , Escherichia coli/patogenicidade , Infecções por Escherichia coli/sangue , Infecções por Escherichia coli/microbiologia , Genes Bacterianos/genética , Genoma Bacteriano , Genótipo , Humanos , Masculino , Filogenia , Pneumonia/microbiologia , Fatores de Virulência/genética , Sequenciamento Completo do Genoma
12.
Mol Carcinog ; 57(7): 896-902, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29566282

RESUMO

Oleanolic acid (OA), a naturally occurring triterpenoid, exhibits potential antitumor activity in several tumor cell lines. Although the inhibition effects of OA on proliferation and survival in human cancers have been confirmed, the potential mechanism underlying OA-induced osteosarcoma cell death has not yet been fully elucidated. Our results in this study showed that OA inhibits proliferation and viability of osteosarcoma cells in a dose-dependent manner. Flow cytometry assays revealed that apoptosis in osteosarcoma cells was significantly induced by OA treatment, while this induction was blocked by Jagged1-mediated activation of Notch signaling. Western blot analysis and a mitochondrial membrane potential assay demonstrated that OA functions through the mitochondrial apoptosis pathway. More importantly, our data revealed that OA treatment interrupted the balance between pro-apoptotic factors and anti-apoptotic factors in osteosarcoma cells by inhibition of the Notch signaling pathway. These data suggest that OA induces osteosarcoma cell apoptosis by targeting mitochondria in a Notch signaling-dependent manner. Thus, OA may be a promising drug for adjuvant chemotherapy in osteosarcoma.


Assuntos
Apoptose/efeitos dos fármacos , Ácido Oleanólico/farmacologia , Osteossarcoma/induzido quimicamente , Osteossarcoma/genética , Receptores Notch/genética , Transdução de Sinais/efeitos dos fármacos , Linhagem Celular Tumoral , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Potencial da Membrana Mitocondrial/genética , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/genética
13.
Microb Pathog ; 116: 168-172, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29360567

RESUMO

The aim of this study is to determine the frequency of virulence genes in high biofilm formation blaKPC-2 producing Klebsiella pneumoniae strains collected over a period of two years. A total of 43 non-repetitive high biofilm blaKPC-2 producing isolates were screened from 429 strains. The MIC of carbapenems (imipenem and meropenem) ranged from 4 to 32 µg/ml. The OD595 value of the biofilm ranged from 0.56 to 2.56. The K1, K2, K5, K20, K54, K57 genotypes, MLST and virulence factors, including entB, ybtS, mrkD, fimH, rmpA, allS, iutA, kfu, wcaG, aerobaction, fecIRA, shiF, magA and pagO gene, were determined by PCR. The results showed that, among the 43 isolates, 5 of 43 were K1 type, 25 of 43 were K2 type, 4 strains and 2 strains were K5 and K57 respectively. The MLST results showed that 23/43 strains were ST11, followed by ST433(4/43), ST107(4/43), ST690(4/43), ST304(2/43), ST2058(1/43), ST1(1/43), ST146(1/43), ST914(1/43), ST2636(1/43), ST2637(1/43). As to the virulence factors, all 43 strains carried entB, ybtS and mrkD gene, followed by fimH(38/43), rmpA(14/43), allS(34/43), iutA(27/43), kfu(25/43), wcaG(21/43), aerobaction(16/43), fecIRA(15/43), shiF(10/43), magA(5/43) and pagO(5/43). This study demonstrated that high frequency of virulence factors emerging in high biofim blaKPC-2 producing strains. It also suggested that we should continue to focus on the toxicity variation and it's high time to enhance clinical awareness to the infections causing by Klebsiella pneumoniae.


Assuntos
Biofilmes/crescimento & desenvolvimento , Infecções por Klebsiella/microbiologia , Klebsiella pneumoniae/enzimologia , Klebsiella pneumoniae/fisiologia , Fatores de Virulência/análise , beta-Lactamases/metabolismo , Carbapenêmicos/farmacologia , Genótipo , Hospitais , Humanos , Klebsiella pneumoniae/genética , Klebsiella pneumoniae/isolamento & purificação , Testes de Sensibilidade Microbiana , Tipagem de Sequências Multilocus , Reação em Cadeia da Polimerase , Fatores de Virulência/genética
14.
Microb Pathog ; 124: 301-304, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30165112

RESUMO

Hypervirulent variants of klebsiella pneumoniae (hvKP), which cause serious infections not only healthy individuals, but also the immunocompromised patients, have been increasingly reported recently. One conjugation of a hypermucoviscous strian SWU01 co-carried the resistance gene blaKPC-2 and virulence gene iroN by the PCR detection from three carbapenem-resistance hvKP. To know the genetic context of this plasmid. The whole genome of this strain was sequenced. We got a 162,552-bp plasmid (pSWU01) which co-carried the resistance gene blaKPC-2 and virulence gene iroN. It is composed of a typical IncFII-type backbone, five resistance genes including blaCTX-M-65, blaKPC-2, blaSHV-12, blaTEM-1 and rmtB, and several virulence relevant factors including iroN, traT and toxin-antitoxin systems. The plasmid pSWU01 co-carrying the multidrug resistance determinants and virulence relevant factors from the hypermucoviscous K. pneumoniae represents a novel therapeutic challenge.


Assuntos
Proteínas de Bactérias/metabolismo , Infecções por Klebsiella/microbiologia , Klebsiella pneumoniae/enzimologia , Fatores de Virulência/metabolismo , beta-Lactamases/metabolismo , Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Humanos , Klebsiella pneumoniae/efeitos dos fármacos , Klebsiella pneumoniae/genética , Metiltransferases/genética , Metiltransferases/metabolismo , Plasmídeos/genética , Plasmídeos/metabolismo , Transporte Proteico , Fatores de Virulência/genética , beta-Lactamases/genética
15.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(4): 1235-9, 2016 Apr.
Artigo em Zh | MEDLINE | ID: mdl-30052354

RESUMO

X-ray tube is the most commonly used equipment in X-ray fluorescence spectrum analysis as excitation source whose primary spectrum has become a major source of the background of X-ray fluorescence spectrum. Background subtraction should go before further analysis of this spectrum. The accuracy of the estimation of the background directly affect the results of subsequent processing steps. In this paper, the tube excitation component of X fluorescence spectrum is analyzed with an estimation method of background intensity against their background characteristics, and structuring theoretical spectral lines based on the measured spectral lines in order to evaluate the effect of spectral processing algorithms. The method utilizes the measured X-ray fluorescence spectrum which does not contain the characteristic peak of the spectrum, In order to estimate the composition of the original spectrum of the X-ray tube. It uses the spectrum that contains the continuous background for interpolating the entire measured spectrum, thereby avoiding overlapping the spectral characteristic peaks or improperly estimating full width at half maximum. This paper compared SNIP, Fourier transform method and the background subtraction method using the measured spectral lines. Using this method to estimate the background is closer to the theoretical background. The results showe that the method for X-ray fluorescence spectrum by X-ray tube excitation is accurate in this article, this method can be used to deduct continuous background, and good applied effectiveness has been achieved in the background subtraction of the actually measured X-ray fluorescence spectrometry.

16.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(4): 1240-4, 2016 Apr.
Artigo em Zh | MEDLINE | ID: mdl-30052355

RESUMO

This paper proposes the analyzing method of adopting wavelength dispersive X-ray fluorescence spectrometry to measure the content of Cu and Zn in PM2.5. PTFE membrane is used to prepare standard samples and atmospheric particulate samples; a research into sample cup's structure,using polypropylene film of 6.7 µm to help to improved sample cup to package atmospheric particulate samples. The improved sample cup is used to measure the content of Cu and Zn in atmospheric particulate, which can obviously reduce background, improve peak/background ratio and decrease detection limit to target element; discussion is made on the measurement condition of Cu and Zn in PM2.5: taking Kα line as analysis line of Cu and Zn, selecting PX10 as analyzer crystal, using 300 µm pitch collimator, adopting scintillation detector for the Kα of Zn, applying the integrating of flow-gas proportional counter and closed-end proportional counter to the Kα of Cu, setting 50 kV, 50 mA as operating voltage and current. The prepared Cu and Zn standard sample is used to set up working curve, the results show that their linear correlations are better, accuracy are higher, relative standard deviations of Cu and Zn are 2.43% and 2.00%(n=8), detection limit are 0.028 and 0.021 µg·cm-2respectively, and analysis of the single sample only need 60 s. To sum up, this method can quickly and accurately analyze the content of Cu and Zn in PM2.5, and provide scientific basis for study the element content characteristics and source apportionment.

17.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(4): 1127-32, 2016 Apr.
Artigo em Zh | MEDLINE | ID: mdl-30052012

RESUMO

The contents of radionuclides uranium, thorium and potassium in the sedimentary rocks mainly depend on the contents of clay in the rocks. And the content of clay is the main basis for distinguishing types of sedimentary rock. Therefore, the value of specific activity or content of uranium, thorium and potassium can be as the quantitative index to distinguish sedimentary rock type. The specific activity or content of radionuclides uranium, thorium and potassium with the method of low-background gamma spectrometry can distinguish the type of rock quickly and accurately. Because of the influence of geometry, mass and moisture content in the sample, the accuracy of distinguishing types of rocks is influenced. This paper makes a theoretical discussion and experimental verification on the influence of mass and moisture content on the results of low-background gamma spectrometry. Results show that there is a linear relationship between (cps) of characteristic peak of all radionuclides and the mass of sample while different energy ranges and lithologies have different linear coefficient and trend fitting degree; The moisture content which is no more than 10%(while collecting samples, the moisture content is no more than 10%) has a little influence on the measurement results( the change values are within the twice standard deviation), so the moisture content which has no significant influence on the accuracy of distinguishing types of sedimentary rock using the method of low-background gamma spectrometry could not be considered. The distinguishing experiment of drilling cuttings samples collected from one oil and gas exploration area in Shanxi Dingbian is done. By the mass correction of the measured data, normalized (cps) ((cps) of per unit mass) of uranium, thorium and potassium channel can only roughly divide the types of sedimentary rocks. Therefore, synthetic distinguishing mode is established with (cps) of combination peak of characteristic peak of uranium, thorium and potassium. The type of rocks is further subdivided, and the distinguishing accuracy is more than 75%.

18.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(7): 2043-8, 2015 Jul.
Artigo em Zh | MEDLINE | ID: mdl-26717776

RESUMO

N, Na, Mg, Al, Si, P, S, Cl, K, Ca, Ti, Cr, Mn, Fe, Ni, Cu, Zn, Br, Rb, Sr, Ba and Pb in herb tea were determined by X-ray fluorescence spectrometry with pressed powder pellets. The measuring conditions of target elements were investigated, including how to select its analytical line. In addition to Ba and Pb using L line, Kalpha line was selected for the rest. When the Compton scattered radiation of Rh Kalpha was measured, The X-ray tube voltage should be appropriately reduced, and the appropriate tube current should be selected. The matrix effect was corrected by empirical coefficient method and using scattered radiation (the Rayleigh scattered radiation of Rh Lalpha, the scattered background of 0.1876 nm wavelength position and the Compton scattered radiation of Rh Kalpha) as internal standard, and the spectral overlapping interference of some elements (N, Na, Ca, Ti, Mn, Sr and Ba) was corrected. For the target elements, the detection limit of this method was low, and its accuracy and precision were high. The results showed that there were abandon of elements in herb tea, of which different kinds had different components, even the same kind of herb tea with different source had some difference in element and content more or less, however, there was a lot of similarity between the features of its components. In a word, this method could achieve multi-element determination of herb tea, and it was simple in operation, low cost, rapid, and accurate.


Assuntos
Espectrometria de Fluorescência , Chás de Ervas/análise , Oligoelementos/análise
19.
Front Biosci (Landmark Ed) ; 29(2): 81, 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38420813

RESUMO

BACKGROUND: Previous clinical studies have suggested that Toll-like receptor (TLR)2 had predictive function for endocrine resistance in HER2-positive breast cancer (BCa). Nevertheless, it remains unclear whether TLR2 would relate to development of endocrine therapy resistance in triple-positive breast cancer (TPBC). METHODS: Bioinformatic analysis of TLR2 was carried out through a database. Ten tumor tissues were obtained from TPBC patients who underwent surgery, with five patients displaying primary resistance to tamoxifen (TAM) with the remaining 5 being sensitive. Different levels of proteins were identified through mass spectrometry analysis and confirmed through reverse transcription polymerase chain reaction (RT-PCR) and western blot. TAM-resistant cell lines (BT474-TAM) were established by continuous exposure to TAM, and TAM resistance was assessed via IC50. Additionally, TLR2 mRNA was analyzed through western blot and RT-PCR in BT474, BT474-TAM, MCF-7, and MCF10A cells. Furthermore, TLR2-specific interference sequences were utilized to downregulate TLR2 expression in BT474-TAM cells to elucidate its role in TAM resistance. RESULTS: TLR2 had a correlation with decreased relapse-free survival in BCa patients from the GSE1456-GPL96 cohort, and it was involved in cancer development predominantly mediated by MAPK and PI3K pathways. TLR2 protein expression ranked in the top 5 proteins within the TAM-resistant group, and was 1.9 times greater than that in the sensitive group. Additionally, TLR2 mRNA and protein expression increased significantly in the established TAM-resistant BT474/TAM cell lines. The sensitivity of TAM was restored upon TLR2 downregulation in BT474/TAM cells. CONCLUSIONS: TLR2 might have a therapeutic value as it was involved in the TAM resistance in TPBC, with potential to be a marker for primary endocrine resistance.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Receptor 2 Toll-Like/genética , Receptor 2 Toll-Like/metabolismo , Receptor 2 Toll-Like/uso terapêutico , Antineoplásicos Hormonais/farmacologia , Antineoplásicos Hormonais/uso terapêutico , Fosfatidilinositol 3-Quinases/metabolismo , Linhagem Celular Tumoral , Transdução de Sinais , Proliferação de Células , Recidiva Local de Neoplasia/tratamento farmacológico , Recidiva Local de Neoplasia/genética , Tamoxifeno/farmacologia , Tamoxifeno/uso terapêutico , RNA Mensageiro/genética , Resistencia a Medicamentos Antineoplásicos/genética , Regulação Neoplásica da Expressão Gênica
20.
Nat Commun ; 15(1): 759, 2024 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-38272905

RESUMO

Anion exchanger 2 (AE2) is an electroneutral Na+-independent Cl-/HCO3- exchanger belongs to the SLC4 transporter family. The widely expressed AE2 participates in a variety of physiological processes, including transepithelial acid-base secretion and osteoclastogenesis. Both the transmembrane domains (TMDs) and the N-terminal cytoplasmic domain (NTD) are involved in regulation of AE2 activity. However, the regulatory mechanism remains unclear. Here, we report a 3.2 Å cryo-EM structure of the AE2 TMDs in complex with PIP2 and a 3.3 Å full-length mutant AE2 structure in the resting state without PIP2. We demonstrate that PIP2 at the TMD dimer interface is involved in the substrate exchange process. Mutation in the PIP2 binding site leads to the displacement of TM7 and further stabilizes the interaction between the TMD and the NTD. Reduced substrate transport activity and conformation similar to AE2 in acidic pH indicating the central contribution of PIP2 to the function of AE2.


Assuntos
Antiporters , Lipídeos , Humanos , Antiportadores de Cloreto-Bicarbonato/genética , Antiporters/genética , Proteínas SLC4A , Mutação , Proteínas de Transporte de Ânions/metabolismo , Concentração de Íons de Hidrogênio
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