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71.

Background

The treatment of Helicobacter pylori (H. pylori) infection is a challenge for those who cannot use amoxicillin.

Objective

To evaluate the eradication rate and adverse effects of vonoprazan and tetracycline dual therapy as first-line and rescue treatment regimens used in special populations with penicillin allergy or failed in previous amoxicillin-containing therapies.

Design

Patients enrolled were those who were H. pylori-positive with selected conditions: (1) allergic to penicillin, either naïve to treatment or had failed before; or (2) failed in previous amoxicillin-containing therapies. All enrolled patients accepted 14-day vonoprazan and tetracycline dual therapy (VT dual therapy) as follows: vonoprazan (20 mg b.i.d.) and tetracycline (500 mg t.i.d. [body weight < 70 kg] or 500 mg q.i.d. [body weight ≥ 70 kg]). H. pylori status was evaluated by 13C-urease breath test 6 weeks after treatment. All adverse effects were recorded. Some patients underwent bacterial culture and antibiotic susceptibility testing.

Results

A total of 62 patients were enrolled; 18 of them received VT dual therapy as first-line treatment, 44 patients received VT dual therapy as rescue treatment. Overall, 58 of 62 patients achieved successful eradication (93.5%), while all involved (100%,18/18) succeeded in the first-line treatment group and 40 cases (90.9%, 40/44) succeeded in the rescue treatment group. Sixty-one (61/62, 98.4%) patients completed the whole course of treatment. Adverse events occurred in 6 patients (6/62, 9.7%), while one patient quit because of skin rash. All adverse effects were mild and relieved spontaneously after H. pylori treatment. Five patients achieved successful H. pylori culture, and all strains isolated were sensitive to tetracycline.

Conclusions

For the treatment of H. pylori infection in special populations with penicillin allergy or failed in previous amoxicillin-containing therapies, a 14-day vonoprazan and tetracycline dual therapy was effective and safe as first-line and rescue treatment in our study. Further study is warranted to verify its efficacy, especially for those who cannot use amoxicillin.  相似文献   
72.
毛梦婷  张瑾  文姣  陈波  廖丽 《微生物学报》2023,63(6):2066-2077
【目的】南极洲具备独特的环境和相对的生物地理隔离,南极洲各类生境中蕴藏了大量尚未培养和难培养的微生物,也是新颖微生物物种的重要来源之一。本研究以南极冰锥洞这类特殊生境为研究对象,通过培养条件的多样化提升南极微生物的培养率和多样性,揭示南极冰锥洞可培养微生物类群多样性,为该环境可培养微生物功能研究奠定基础,也为南极极端环境未培养微生物的培养方法提供借鉴。【方法】通过采用不同培养基添加复苏促进因子(resuscitation promoting factor, Rpf)的方式,提高南极柯林斯冰盖冰锥洞生境中微生物的可培养率,探究该生境中微生物的多样性。采用4种不同营养水平的培养基,平行添加Rpf进行菌株培养,经分离纯化与16S rRNA基因鉴定,分析冰锥洞可培养微生物的多样性及培养条件对多样性的影响。【结果】本研究共分离培养细菌407株,涵盖5个门、18个科、29个属,其中:放线菌门(Actinomycetota)为优势门,占72.73%;微杆菌科(Microbacteriaceae)为优势科,占69.78%;Lacisediminihabitans属为优势属,占45.70%。从培养基效果...  相似文献   
73.
氯化镧对玉米根切段钾离子外渗影响的动力学研究   总被引:9,自引:0,他引:9  
研究了氯化镧对玉米(Zea mays L.)“京早8号”根切段细胞膜透性及质子分泌的影响,并用动力学方法研究了钾离子外渗过程的变化。氯化镧处理可降低外渗液的电导率及K~ 和糖的外渗量,使质子分泌活动增强。用动力学方法分析玉米根切段K~ 外渗过程的结果表明:(1)应用于K~ 吸收研究的数学模型也能适应于K~ 外渗的研究;(2)在LaCl_3和(或)CaCl_2存在的条件下,最大吸收速度(V_(max))升高,而米氏常数(K_m)没有变化;(3)在LaCl_3和(或)CaCl_2存在的条件下,K~ 外渗量降低是由于最大吸收速度(V_(max))升高所致。  相似文献   
74.
代梨梨  彭亮  陶玲  郝柳柳  张辉  李谷 《微生物学报》2023,63(10):3811-3824
硫酸盐引起的生态学效应已得到了越来越多的关注,但目前关于硫酸盐对养殖池塘底泥微生物的影响还知之甚少。【目的】探究不同浓度硫酸盐对养殖池塘底泥微生物的影响规律及可能的机制。【方法】本研究利用采集自养殖池塘的底泥和表层水构建了试验系统,研究了加入约0 mg/L (对照组)、30 mg/L (T1处理组)、150 mg/L (T2处理组)、500 mg/L (T3处理组) Na2SO4后表层底泥微生物的丰度、多样性、组成和共生网络的变化规律,并分析了环境影响因素。【结果】孵育第30天前,各实验组底泥微生物变化不大;但到第50天时,T2和T3处理组微生物丰度和多样性相比对照组均明显下降。相比其他实验组,T1处理组酸杆菌门(Acidobacteriota)、拟杆菌门(Bacteroidota)相对丰度出现显著升高(P<0.05),T3处理组变形菌门(Proteobacteria)和放线菌门(Actinobacteriota)相对丰度出现显著升高(P<0.05)。与对照组相比,T1处理组增加了较多差异类群(62种),而T3处理组差异类群大量减少(45种)。共生网络图分析显示硫酸盐浓度的增加引起了底泥微生物网络复杂性的增加,说明微生物群落可能通过自身的调节来响应硫酸盐引起的环境改变。冗余分析(redundant analysis,RDA)和相关性分析揭示底泥总有机碳、总氮和氧化还原电位是影响底泥微生物的主要环境因素,提示底泥微生物可能受到硫酸盐和有机质作用的影响。【结论】较长时间的高浓度硫酸盐会对池塘底泥微生物群落造成重要影响,微生物群落自身的转变和硫酸盐引起的有机质分解改变可能是造成微生物群落变化的关键因素。  相似文献   
75.
【目的】对分离自健康成人粪便样本的棒状腐败乳杆菌(Loigolactobacillus coryniformis)Lc7进行分类学鉴定和益生潜力评估。【方法】基于16SrRNA基因和基因组核心基因构建系统发育树,对Lc7进行分类学鉴定;通过耐酸和胆汁酸盐、粘附、抗氧化和抑菌实验,以及溶血、明胶酶活性和抗菌药物敏感性实验,评估Lc7的益生特性。同时,构建小鼠溃疡性结肠炎模型,评估Lc7的体内抗炎潜力。【结果】Lc7鉴定为L. coryniformis,在酸和胆汁酸盐的连续作用下,Lc7的存活率为70.17%。Lc7对HT-29细胞的粘附指数为56.33 CFU/cell,其自聚集和疏水性分别为80%和40%;Lc7对福氏志贺菌和鼠伤寒沙门菌等7个常见致病菌均有较强的抑制能力;对1,1-二苯基-2-苦基肼(1,1-diphenyl-2-picryl-hydrazyl,DPPH)和羟自由基(hydroxyl radicals,·OH)的清除率分别为91.70%和48.53%;Lc7无溶血现象和明胶酶活性,对选取的大多数抗生素均敏感。在小鼠结肠炎实验中,Lc7干预组小鼠结肠长度明显长于模型组(...  相似文献   
76.
Mitogen-activated protein kinase (MAPK) cascades play pivotal roles in plant responses to both biotic and abiotic stress. A screen of a Nicotiana benthamiana cDNA virus-induced gene silencing (VIGS) library for altered plant responses to inoculation with Phytophthora infestans previously identified an NbMKK gene, encoding a clade D MAPKK that we renamed as NbMKK5, which is involved in immunity to P. infestans. To study the role of the potato orthologous gene, referred to as StMKK5, in the response to P. infestans, we transiently overexpressed StMKK5 in N. benthamiana and observed that cell death occurred at 2 days postinfiltration. Silencing of the highly conserved eukaryotic protein SGT1 delayed the StMKK5-induced cell death, whereas silencing of the MAPK-encoding gene NbSIPK completely abolished the cell death response. Further investigations showed that StMKK5 interacts with, and directly phosphorylates, StSIPK. Furthermore, both StMKK5 and StSIPK trigger salicylic acid (SA)- and ethylene (Eth)-related gene expression, and co-expression of the salicylate hydroxylase NahG with the negative regulator of Eth signalling CTR1 hampers StSIPK-triggered cell death. This observation indicates that the cell death triggered by StMKK5-StSIPK is dependent on the combination of SA- and Eth-signalling. By introducing point mutations, we showed that the kinase activity of both StMKK5 and StSIPK is required for triggering cell death. Genetic analysis showed that StMKK5 depends on StSIPK to trigger plant resistance. Thus, our results define a potato StMKK5-SIPK module that positively regulates immunity to P. infestans via activation of both the SA and Eth signalling pathways.  相似文献   
77.
Zanthoxylum armatum and Zanthoxylum bungeanum, known as ‘Chinese pepper’, are distinguished by their extraordinary complex genomes, phenotypic innovation of adaptive evolution and species-special metabolites. Here, we report reference-grade genomes of Z. armatum and Z. bungeanum. Using high coverage sequence data and comprehensive assembly strategies, we derived 66 pseudochromosomes comprising 33 homologous phased groups of two subgenomes, including autotetraploid Z. armatum. The genomic rearrangements and two whole-genome duplications created large (~4.5 Gb) complex genomes with a high ratio of repetitive sequences (>82%) and high chromosome number (2n = 4x = 132). Further analysis of the high-quality genomes shed lights on the genomic basis of involutional reproduction, allomones biosynthesis and adaptive evolution in Chinese pepper, revealing a high consistent relationship between genomic evolution, environmental factors and phenotypic innovation. Our study provides genomic resources and new insights for investigating diversification and phenotypic innovation in Chinese pepper, with broader implications for the protection of plants under severe environmental changes.  相似文献   
78.
Grain size and filling are two key determinants of grain thousand-kernel weight (TKW) and crop yield, therefore they have undergone strong selection since cereal was domesticated. Genetic dissection of the two traits will improve yield potential in crops. A quantitative trait locus significantly associated with wheat grain TKW was detected on chromosome 7AS flanked by a simple sequence repeat marker of Wmc17 in Chinese wheat 262 mini-core collection by genome-wide association study. Combined with the bulked segregant RNA-sequencing (BSR-seq) analysis of an F2 genetic segregation population with extremely different TKW traits, a candidate trehalose-6-phosphate phosphatase gene located at 135.0 Mb (CS V1.0), designated as TaTPP-7A, was identified. This gene was specifically expressed in developing grains and strongly influenced grain filling and size. Overexpression (OE) of TaTPP-7A in wheat enhanced grain TKW and wheat yield greatly. Detailed analysis revealed that OE of TaTPP-7A significantly increased the expression levels of starch synthesis- and senescence-related genes involved in abscisic acid (ABA) and ethylene pathways. Moreover, most of the sucrose metabolism and starch regulation-related genes were potentially regulated by SnRK1. In addition, TaTPP-7A is a crucial domestication- and breeding-targeted gene and it feedback regulates sucrose lysis, flux, and utilization in the grain endosperm mainly through the T6P-SnRK1 pathway and sugar–ABA interaction. Thus, we confirmed the T6P signalling pathway as the central regulatory system for sucrose allocation and source–sink interactions in wheat grains and propose that the trehalose pathway components have great potential to increase yields in cereal crops.  相似文献   
79.
This paper reports a sequence of a Ca3YAl3B4O15:xEu3+ red phosphor prepared using a high-temperature solid-state reaction. At the excitation of 396 nm, the samples emitted intense red emission centred at ~623 nm, which could be attributed to the 5D07F2 transition of the Eu3+ ion. The results showed that the optimum Eu3+ doping concentration of Ca3YAl3B4O15:Eu3+ phosphor was x = 80 mol%, and the concentration quenching mechanism of Ca3YAl3B4O15:Eu3+ red phosphor belonged to the exchange coupling between Eu3+ ions. The Commission Internationale de l'éclairage (CIE) coordinates and colour purity of Ca3Y0.2Al3B4O15:0.8Eu3+ were calculated as (0.6375, 0.3476) and 95.5%, respectively. Moreover, the red emission of the obtained phosphor Ca3YAl3B4O15:0.8Eu3+ exhibited a low thermal quenching behaviour with an intensity retention rate of 92.85% at 150°C. The above results manifest that the Eu3+-activated Ca3YAl3B4O15 phosphor is predicted to be a promising red luminescent component for white light-emitting diodes.  相似文献   
80.
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