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1.
Int J Biol Macromol ; 278(Pt 3): 134898, 2024 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-39173793

RESUMEN

Edwardsiella tarda is an intracellular pathogenic bacteria that can imperil the health of farmed fish. However, the interactive networks of immune regulation and metabolic response in E. tarda-infected fish are still unclear. In this investigation, we aimed to explore immunometabolic interplay in crucian carp after E. tarda infection by utilizing multiomics analyses. Crucian carp (Carassius auratus) receiving E. tarda infection showed increased levels of tissue damage and oxidative injury in liver. Multiomics analyses suggested that carbon and amino acid metabolism may be considered as crucial metabolic pathways in liver of crucian carp following E. tarda infection, while spaglumic acid, isocitric acid and tetrahydrocortisone were the crucial liver biomarkers. After that, a potential antimicrobial peptide (AMP) sequence called apolipoprotein D (ApoD) was identified from omics study. Then, tissue-specific analysis indicated that liver CaApoD showed the highest expression among isolated tissues. After Aeromonas hydrophila stimulated, CaApoD expressions increased sharply in immune-related tissues. Moreover, CaApoD fusion protein could mediate the in vitro binding to A. hydrophila and E. tarda, attenuate bacterial growth as well as diminish bacterial biofilm forming activity. These findings may have a comprehensive implication for understanding immunometabolic response in crucian carp upon infection.

2.
Bioresour Technol ; 408: 131228, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39117239

RESUMEN

A novel A. pittii J08 with heterotrophic nitrification and aerobic denitrification (HN-AD) isolated from pond sediments could rapidly degrade inorganic nitrogen (N) and total nitrogen (TN-N) with ammonium (NH4+-N) preference. N degradation rate of NH4+-N, nitrite (NO2--N) and nitrate (NO3--N) were 3.9 mgL-1h-1, 3.0 mgL-1h-1 and 2.7 mgL-1h-1, respectively. In addition, strain J08 could effectively utilize most of detected low-molecular-weight carbon (LMWC) sources to degrade inorganic N with a wide adaptability to various culture conditions. Whole genome sequencing (WGS) analysis revealed that assembled genome of stain J08 possessed the crucial genes involved in dissimilatory/assimilatory NO3--N reduction and NH4+-N assimilation. These results indicated that strain J08 could be applied to wastewater treatment in aquaculture.


Asunto(s)
Acinetobacter , Nitrógeno , Nitrógeno/metabolismo , Acinetobacter/metabolismo , Acinetobacter/genética , Genoma Bacteriano , Desnitrificación , Compuestos de Amonio/metabolismo , Genómica/métodos , Nitratos/metabolismo , Biodegradación Ambiental , Nitrificación , Nitritos/metabolismo , Filogenia , Aguas Residuales/microbiología , Secuenciación Completa del Genoma
3.
Fish Physiol Biochem ; 2024 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-39066864

RESUMEN

As a major source of energy, carbohydrates have a protein-saving effect. However, excessive consumption of carbohydrates can lead to the disruption of the intestinal barrier in fish, especially for carnivorous fish. Therefore, traditional Chinese medicine component Yinchenhao Decoction (YD), was used to detect the effect on intestinal barriers and microbial community equilibrium for largemouth bass in current research. In this research, a series of NC (normal carbohydrate diet) and HC (high carbohydrate diet) with graded YD treatments during 10 weeks feeding trial. Results suggested that 2% and 4% YD treatments significantly reduced gut inflammation and mucosal loss caused by HC. Compared with NC, HC significantly decreased the relative expression of intestinal tight junction-related genes (zo1, claudin1, claudin7, and occludin). However, with the application of YD, the expression of tight junction-related genes (zo1, claudin1, and claudin7) increased significantly (p < 0.05). Likewise, administration of YD significantly reduced elevated plasma diamine oxidase (DAO) activity caused by HC (p < 0.05). Additionally, YD significantly downregulated the mRNA expression of endoplasmic reticulum stress (ERS)-related genes (grp78, atf6, chopα, ire1, xbp1, and eifα) and pro-apoptosis genes (casp3, casp8, and bax) (p < 0.05), while upregulating the anti-apoptosis gene bcl2 (p < 0.05). Moreover, YD significantly increased the mRNA expression of antioxidant genes and the enzyme activities of CAT and GPX, while decreased MDA concentration significantly (p < 0.05). Whereas, YD markedly decreased the expression of pro-inflammatory genes (il1ß, tnfα, il8, and nf-κB) and the immune enzymes activity (ACP and AKP) (p < 0.05) by up-regulating the expression of anti-inflammatory genes (ikb and il10). Notably, YD modulated the largemouth bass intestinal microbial community, enhanced the diversity and increased the abundance of probiotic microorganisms in the intestinal microbiota. In summary, YD supplementation in HC alleviated inflammation, apoptosis, oxidative stress, tight-junction injury, and microbiota disequilibrium in the intestine, which suggested that YD could be a valuable functional additive in aquaculture.

4.
Environ Sci Pollut Res Int ; 30(56): 119217-119227, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37922075

RESUMEN

Triphenyl phosphate (TPhP) is the predominant compound of organophosphate flame retardants (OPFRs), which can elicit a toxicological effect on physiological response and tissue development of fish. In this study, we investigated the effect of TPhP exposure on cell viability, antioxidant capacities, and apoptosis in EPC cells. Current study revealed that TPhP exposure could decrease cell viability and promote intracellular oxidative stress in EPC cells. In addition, high-dose TPhP exposure could facilitate antioxidant insults and cause mitochondrial collapse in a dose-dependent manner, along with increased gene expressions involved in apoptosis and unfolded protein response (UPR). These results indicated that reactive oxygen species (ROS)-induced cytotoxic stress and cell death were involved in antioxidant insults and apoptotic activation in TPhP-exposed fish cells.


Asunto(s)
Carcinoma , Retardadores de Llama , Animales , Antioxidantes/metabolismo , Regulación hacia Arriba , Organofosfatos/toxicidad , Apoptosis , Estrés Oxidativo , Retardadores de Llama/toxicidad , Retardadores de Llama/metabolismo
5.
Artículo en Inglés | MEDLINE | ID: mdl-36707042

RESUMEN

Aeromonas hydrophila can pose a great threat to fish survival. In this study, we investigated the differential immune and redox response in gut-liver axis of hybrid fish (WR) undergoing gut infection. WR anally intubated with A. hydrophila showed severe midgut injury with decreased length-to-width ratios of villi along with GC hyperplasia and enhanced antioxidant activities, but expression profiles of cytokines, chemokines, antibacterial molecules, redox sensors and tight junction proteins decreased dramatically. In contrast, immune-related gene expressions and antioxidant activities increased significantly in liver of WR following gut infection with A. hydrophila. These results highlighted the differential immune regulation and redox balance in gut-liver axis response to bacterial infection.


Asunto(s)
Carpas , Enfermedades de los Peces , Animales , Carpa Dorada/metabolismo , Aeromonas hydrophila/fisiología , Antioxidantes/metabolismo , Proteínas de Peces/metabolismo , Hígado/metabolismo , Oxidación-Reducción , Enfermedades de los Peces/microbiología , Carpas/metabolismo , Inmunidad Innata
6.
Front Microbiol ; 13: 912260, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35847092

RESUMEN

We conducted a molecular surveillance study for carbapenem-resistant Enterobacteriaceae (CRE) colonization in food-producing animals in China that included primarily swine and poultry for three consecutive years. A total of 2,771 samples from food-producing animals and their surrounding environments were collected from different regions in China from 2015 to 2017. Enrichment cultures supplemented with meropenem were used to isolate carbapenem non-susceptible isolates and these were subsequently identified by MALDI-TOF MS. Resistance phenotypes and genotypes were confirmed using antimicrobial susceptibility testing and molecular biological techniques. Genomic characteristics of the carbapenemase-producing isolates were investigated using whole genome sequencing (WGS) and bioinformatic analysis. In total, 88 NDM-positive Enterobacteriaceae were identified from 2,771 samples and 96.6% were Escherichia coli. The New Delhi metallo-ß-lactamase (NDM)-positive E. coli displayed a diversity of sequence types (ST), and ST48 and ST165 were the most prevalent. Three variants of bla NDM (bla NDM-1, bla NDM-4, and bla NDM-5) were detected and WGS indicated that bla NDM-5 predominated and was carried primarily on IncX3 plasmids. All these isolates were also multiply-drug resistant. These results revealed that food-producing animals in China are an important reservoir for NDM-positive E. coli and pose a potential threat to public health.

7.
J Fish Dis ; 45(10): 1491-1509, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35749280

RESUMEN

Aeromonas hydrophila is a common pathogen of freshwater fish. In this study, A. hydrophila infection was shown to cause tissue damage, trigger physiological changes as well as alter the expression profiles of immune- and metabolic-related genes in immune tissues of red crucian carp (RCC). Transcriptome analysis revealed that acute A. hydrophila infection exerted a profound effect on mitochondrial oxidative phosphorylation linking metabolic regulation to immune response. In addition, we further identified cellular senescence, apoptosis, necrosis and mitogen-activated protein kinase signal pathways as crucial signal pathways in the kidney of RCC subjected to A. hydrophila infection. These findings may have important implications for understanding modulation of immunometabolic response to bacterial infection.


Asunto(s)
Carcinoma de Células Renales , Carpas , Enfermedades de los Peces , Infecciones por Bacterias Gramnegativas , Neoplasias Renales , Aeromonas hydrophila/fisiología , Animales , Carpas/metabolismo , Enfermedades de los Peces/microbiología , Proteínas de Peces/metabolismo , Perfilación de la Expresión Génica/veterinaria , Carpa Dorada/genética , Infecciones por Bacterias Gramnegativas/microbiología , Mitocondrias/genética , Mitocondrias/metabolismo , Transcriptoma
8.
Animals (Basel) ; 12(10)2022 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-35625156

RESUMEN

Carbapenem and colistin are important antibiotics for the treatment of infections caused by multidrug-resistant Gram-negative pathogens. Here, we isolated the blaNDM-5-harboring Escherichia coli in companion animals in healthy or diseased companion animals from veterinary clinics in six cities in China from July to November 2016. A total of 129 rectal swabs of healthy or diseased dogs and cats were collected from veterinary clinics in six different cities in China, and the isolates were subjected to carbapenem and colistin susceptibility testing. Resistance genes were confirmed using PCR. Conjugation experiments were conducted to determine the transferability of antibiotic resistance genes (ARGs) in the strains. The isolated rate of blaNDM-5-harboring E. coli strains was 3.88% (five strains). These five strains were multidrug resistant to at least three antibiotics and corresponded to four sequence types including ST101. The blaNDM-5 gene was located on 46 kb IncX3 plasmids in these five strains, and the genetic contexts were shared and were nearly identical to the K. pneumoniae plasmid pNDM5-IncX3 from China. In addition, one strain (CQ6-1) co-harbored blaNDM-5-encoding-IncX3 plasmid along with a mcr-1-encoding-IncX4 plasmid, and their corresponding genetic environments were identical to the blaNDM-5-IncX3 and mcr-1-IncX4 hybrid plasmid reported previously from the same area and from the same clinic. The results indicated that the similar genetic contexts were shared between these isolates from companion animals, and the IncX3-type plasmids played a key role in the spread of blaNDM-5 among these bacteria.

9.
Appl Environ Microbiol ; 88(8): e0245721, 2022 04 26.
Artículo en Inglés | MEDLINE | ID: mdl-35389252

RESUMEN

We retrospectively investigated 326 samples that were collected from goose farms in Hainan Province, China, in 2017. A total of 33 carbapenem-resistant Klebsiella pneumoniae (CRKP) isolates were identified from 326 samples, and the 33 CRKP isolates were characterized based on whole-genome sequencing (WGS) data from the Illumina and Oxford Nanopore Technologies (ONT) platforms. All of these 33 CRKP isolates possessed blaNDM-5, and a single isolate coharbored mcr-1 and blaNDM-5, while 4 isolates carried multiple virulence and metal tolerance gene clusters. One CRKP strain (CMG-35-2) was selected for long sequence reading. A hybrid plasmid carrying the virulence, resistance, and metal resistance gene in the strain was found. It possessed 2 backbones [IncFIB(K)-IncFII(K)] within a single plasmid that were closely related to K. pneumoniae plasmids from a human-associated habitat in the United States and from a human isolate in Hong Kong. A mouse abdominal infection model indicated that that strain was of the moderate virulence phenotype. This study revealed that K. pneumoniae on goose farms is an important reservoir for blaNDM-5 and these bacteria are represented by a diversity of sequence types. The heterozygous multiple drug resistance genes carried on plasmids highlighted the genetic complexity of CRKP and the urgent need for continued active surveillance. IMPORTANCE CRKP is one of the most important pathogens, which can cause infection not only in humans but also in waterfowl. The discovery of blaNDM-5-producing K. pneumoniae in waterfowl farms in recent years suggests that waterfowl are an important reservoir for blaNDM-5-producing Enterobacteriaceae. However, there are few studies on the spread of blaNDM-5-producing bacteria in waterfowl farms. Our study showed that the IncX3 plasmid carrying blaNDM-5 in goose farms is widely present in K. pneumoniae isolates and a large number of resistance genes are accumulated in it. We found a transferable IncFIB-FII hybrid plasmid that combines virulence, resistance, and metal resistance genes, which allow transfer of these traits between bacteria in different regions. The results of this study contribute to a better understanding of the prevalence and transmission of carbapenem-resistant K. pneumoniae in goose farms.


Asunto(s)
Antibacterianos , Klebsiella pneumoniae , Animales , Antibacterianos/farmacología , Carbapenémicos , Farmacorresistencia Bacteriana/genética , Granjas , Gansos , Ratones , Estudios Retrospectivos , Virulencia/genética , beta-Lactamasas/genética
10.
Fish Shellfish Immunol ; 120: 547-559, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34923115

RESUMEN

Aeromonas hydrophila can pose a great threat to survival of freshwater fish. In this study, A. hydrophila infection could decrease blood cell numbers, promote blood cell damage as well as alter the levels of alkaline phosphatase (ALP), lysozyme (LZM), aspartate aminotransferase (AST), total antioxidant capacity (T-AOC), total superoxide dismutase (SOD), catalase (CAT) and malondialdehyde (MDA) in immune-related tissues of red crucian carp (RCC, 2 N = 100) and triploid cyprinid fish (3 N fish, 3 N = 150). In addition, the significant alternation of antioxidant status was observed in PBMCs isolated from RCC and 3 N following LPS stimulation. The core differential expression genes (DEGs) involved in apoptosis, immunity, inflammation and cellular signals were co-expressed differentially in RCC and 3 N following A. hydrophila challenge. NOD-like receptor (NLR) signals appeared to play a critical role in A. hydrophila-infected fish. DEGs of NLR signals in RCCah vs RCCctl were enriched in caspase-1-dependent Interleukin-1ß (IL-1ß) secretion, interferon (IFN) signals as well as cytokine activation, while DEGs of NLR signals in 3Nah vs 3Nctl were enriched in caspase-1-dependent IL-1ß secretion and antibacterial autophagy. These results highlighted the differential signal regulation of different ploidy cyprinid fish to cope with bacterial infection.


Asunto(s)
Carpas , Enfermedades de los Peces , Infecciones por Bacterias Gramnegativas , Transcriptoma , Aeromonas hydrophila , Animales , Antioxidantes , Células Sanguíneas , Carpas/genética , Carpas/inmunología , Caspasas , Suplementos Dietéticos , Resistencia a la Enfermedad , Enfermedades de los Peces/inmunología , Enfermedades de los Peces/microbiología , Proteínas de Peces/genética , Perfilación de la Expresión Génica , Infecciones por Bacterias Gramnegativas/inmunología , Infecciones por Bacterias Gramnegativas/veterinaria , Inmunidad Innata , Ploidias
11.
Front Microbiol ; 12: 755233, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34745062

RESUMEN

We determined the prevalence and transmission characteristics of mcr-1-positive Escherichia coli (MCRPEC) isolates from migratory birds Anser indicus in Guangdong, China. We identified 22 MCRPEC from 303 A. indicus fecal samples (7.3%) in Guangzhou, Zhaoqing, and Futian. The mcr-1 gene coexisted with 24 other types of antibiotic resistance genes (ARG), and 11 ARGs were highly prevalent at levels >50%. The MCRPEC displayed a diversity of sequence types (ST), and 19 distinct STs were identified with ST10, ST1146, and ST1147 as the most prevalent. In addition, these MCRPEC from birds were closely related phylogenetically to those from other sources in China. Whole-genome sequencing analysis demonstrated that mcr-1 was located on IncX4 (n=9, 40.9%), IncI2 (n=5, 22.7%) and IncP (n=1, 4.5%) plasmids and the latter shared an identical plasmid backbone with other sources. These results highlight the significance of migratory birds in the transmission of antibiotic resistance and provide powerful evidence that migratory birds are potential transmitters of antibiotic resistance.

12.
Medicine (Baltimore) ; 100(46): e27686, 2021 Nov 19.
Artículo en Inglés | MEDLINE | ID: mdl-34797294

RESUMEN

INTRODUCTION: Patients with amnesic mild cognitive impairment (aMCI) are more likely to develop Alzheimer disease than corresponding age normal population. Because Alzheimer disease is irreversible, early intervention for aMCI patients seems important and urgent. We have designed a pilot multicenter, randomized, parallel controlled trial to assess the efficacy and safety of acupuncture on aMCI, explore the feasibility of acupuncture in the treatment of aMCI, so as to provide a reference for large-sample clinical trials in the next stage. METHOD: We designed a pilot multicenter, randomized, parallel controlled trial. This trial aims to test the feasibility of carrying out a large-sample clinical trial. In this trial, 50 eligible patients with aMCI will be included and allocated to acupuncture group (n = 25) or sham acupuncture group (n = 25) at random. Subjects will accept treatment 2 times a week for 12 weeks continuously, with a total of 24 treatment sessions. We will select 6 acupoints (GV20, GV14, bilateral BL18, bilateral BL23). For the clinical outcomes, the primary outcome is Montreal cognitive assessment, which will be assessed from baseline to the end of this trial. And the secondary outcomes are Mini-mental State Examination, Delayed Story Recall, Clinical Dementia Rating scale, Global Deterioration Scale, Activity of Daily Life, Alzheimer Disease Assessment Scale-Cognitive Section, brain magnetic resonance imaging, brain functional magnetic resonance imaging, and event-related potential P300, which will be assessed before and after treatment. In addition, we will assess the safety outcomes from baseline to the end of this trial and feasibility outcome after treatment. We will evaluate neuropsychological assessment scale (Montreal cognitive assessment, Mini-mental State Examination, Alzheimer Disease Assessment Scale-Cognitive Section) at 3 months and 6 months after treatment. DISCUSSION: This pilot trial aims to explore the feasibility of the trial, verify essential information of its efficacy and safety. This pilot study will provide a preliminary basis for carrying out a larger clinical trial of acupuncture on aMCI in near future.


Asunto(s)
Terapia por Acupuntura/métodos , Enfermedad de Alzheimer/terapia , Disfunción Cognitiva/terapia , Enfermedad de Alzheimer/diagnóstico , Amnesia/terapia , Disfunción Cognitiva/diagnóstico , Manual Diagnóstico y Estadístico de los Trastornos Mentales , Estudios de Factibilidad , Humanos , Pruebas de Estado Mental y Demencia , Proyectos Piloto , Resultado del Tratamiento
13.
J Antimicrob Chemother ; 77(1): 74-82, 2021 12 24.
Artículo en Inglés | MEDLINE | ID: mdl-34613377

RESUMEN

OBJECTIVES: In this study, we developed an IS26-based CRISPR/Cas9 system as a proof-of-concept study to explore the potential of a re-engineered bacterial translocatable unit (TU) for curing and immunizing against the replication genes and antimicrobial resistance genes. METHODS: A series of pIS26-CRISPR/Cas9 suicide plasmids were constructed, and specific guide RNAs were designed to target the replication gene of IncX4, IncI2 and IncHI2 plasmids, and the antibiotic resistance genes mcr-1, blaKPC-2 and blaNDM-5. Through conjugation and induction, the transposition efficiency and plasmid-curing efficiency in each recipient were tested. In addition, we examined the efficiency of the IS26-CRISPR/Cas9 system of cell immunity against the acquisition of the exogenous resistant plasmids by introducing this system into antimicrobial-susceptible hosts. RESULTS: This study aimed to eliminate the replication genes and antimicrobial resistance genes using pIS26-CRISPR/Cas9. Three plasmids with different replicon types, including IncX4, IncI2 and IncHI2 in three isolates, two pUC19-derived plasmids, pUC19-mcr-1 and pUC19-IS26mcr-1, in two lab strains, and two plasmids bearing blaKPC-2 and blaNDM-5 in two isolates were all successfully eliminated. Moreover, the IS26-based CRISPR/Cas9 system that remained in the plasmid-cured strains could efficiently serve as an immune system against the acquisition of the exogenous resistant plasmids. CONCLUSIONS: The IS26-based CRISPR/Cas9 system can be used to efficiently sensitize clinical Escherichia coli isolates to antibiotics in vitro. The single-guide RNAs targeted resistance genes or replication genes of specific incompatible plasmids that harboured resistance genes, providing a novel means to naturally select bacteria that cannot uptake and disseminate such genes.


Asunto(s)
Sistemas CRISPR-Cas , Proteínas de Escherichia coli , Escherichia coli , Antibacterianos/farmacología , Farmacorresistencia Bacteriana/genética , Escherichia coli/genética , Proteínas de Escherichia coli/genética , Plásmidos/genética
14.
Front Microbiol ; 12: 716393, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34497596

RESUMEN

OBJECTIVES: Carbapenems, colistin, and tigecycline are critically important antibiotics in clinics. After the global appearance of bla NDM and mcr mediating the resistance to carbapenems and colistin, respectively, tigecycline becomes the last-resort drug against severe human infections caused by multidrug-resistant bacteria. Recently, a mobile tigecycline resistance gene tet(X4) has been identified in Escherichia coli, Klebsiella pneumoniae, and Acinetobacter baumannii that causes high resistance to tigecycline and other tetracyclines. In this study, the prevalence of tet(X4) in E. coli isolates from duck and goose farms in Southeast China was identified and characterized. METHODS: Feces, soil, sewage, and dust samples were collected from duck and goose farms along with the southeast coast provinces of China. Antimicrobial susceptibility testing and polymerase chain reaction screening were performed to investigate the phenotype and genotype of tigecycline resistance. Conjugation, S1 pulsed-field gel electrophoresis (PFGE), and whole-genome sequencing were used to determine the transferability, genetic location, and the genomic characteristics of tet(X4). RESULTS: In total, 1,716 samples were collected, and 16 isolates (0.9%) recovered from Guangdong, Shandong, and Jiangsu were positive for tet(X4) gene with tigecycline minimum inhibitory concentrations ≥16 mg/L. Notably, among these tet(X4)-positive E. coil isolates, seven of them were from the environment samples (soil and sewage). PFGE and multilocus sequence typing demonstrated that ST3997 was the most prevalent sequence type (eight isolates, 50%) in Jiangsu province. By conjugation assays, 11 isolates were able to transfer tet(X4) plasmid to E. coli C600 recipient, and these plasmids belonged to IncHI1 and IncX1 detected by sequence analysis. tet(X4) was found adjacent to an insertion sequence ISCR2 downstream and a catD gene upstream for all isolates. In addition, multiple-drug resistance to tigecycline, chlortetracycline, ampicillin, florfenicol, ciprofloxacin, gentamicin, trimethoprim/sulfamethoxazole, and fosfomycin was profiled in most of the tet(X4)-positive isolates. CONCLUSION: The identification of tet(X4) harboring E. coli strains in duck farms and their surrounding environment enlarges our knowledge of the variety and prevalence of tigecycline resistance. The prevalence of tet(X4) raises concern for the use of tetracyclines in animal farming, and the tet(X4) gene should be listed as primary gene for resistance surveillance.

15.
Antimicrob Agents Chemother ; 65(10): e0105421, 2021 09 17.
Artículo en Inglés | MEDLINE | ID: mdl-34339270

RESUMEN

The global spread of antimicrobial-resistant bacteria has been one of the most severe threats to public health. The emergence of the mcr-1 gene has posed a considerable threat to antimicrobial medication since it deactivates one last-resort antibiotic, colistin. There have been reports regarding the mobilization of the mcr-1 gene facilitated by ISApl1-formed transposon Tn6330 and mediated rapid dispersion among Enterobacteriaceae species. Here, we developed a CRISPR/Cas9 system flanked by ISApl1 in a suicide plasmid capable of exerting sequence-specific curing against the mcr-1-bearing plasmid and killing the strain with chromosome-borne mcr-1. The constructed ISApl1-carried CRISPR/Cas9 system either restored sensitivity to colistin in strains with plasmid-borne mcr-1 or directly eradicated the bacteria harboring chromosome-borne mcr-1 by introducing an exogenous CRISPR/Cas9 targeting the mcr-1 gene. This method is highly efficient in removing the mcr-1 gene from Escherichia coli, thereby resensitizing these strains to colistin. The further results demonstrated that it conferred the recipient bacteria with immunity against the acquisition of the exogenous mcr-1 containing the plasmid. The data from the current study highlighted the potential of the transposon-associated CRISPR/Cas9 system to serve as a therapeutic approach to control the dissemination of mcr-1 resistance among clinical pathogens.


Asunto(s)
Proteínas de Escherichia coli , Escherichia coli , Antibacterianos/farmacología , Sistemas CRISPR-Cas/genética , Cromosomas , Colistina/farmacología , Farmacorresistencia Bacteriana/genética , Escherichia coli/genética , Proteínas de Escherichia coli/genética , Humanos , Plásmidos/genética
16.
Acupunct Med ; 39(6): 577-588, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34074151

RESUMEN

OBJECTIVES: The aim of this study was to evaluate the effectiveness and safety of acupuncture for the treatment of post-stroke cognitive impairment (PSCI). METHODS: The Cochrane Library, Embase, Medline, China National Knowledge Infrastructure (CNKI), Chinese Science and Technology Periodical (VIP), Wanfang, and Chinese Biological Medicine (CBM) databases were electronically searched from their inception to 10 April 2019. The Montreal Cognitive Assessment (MoCA) scale and Mini-Mental State Examination (MMSE) scale were used as outcomes to assess effectiveness with respect to cognitive function. Assessment of risk of bias (ROB) and Grading of Recommendations Assessment, Development, and Evaluation (GRADE) assessment were performed by two reviewers independently. Data were analyzed using Review Manager (RevMan) 5.3. RESULTS: A total of 28 trials with 2144 participants were included in the qualitative synthesis and meta-analysis. Four of the 28 trials (14%) were assessed as being at overall low ROB, 24 of the 28 trials (86%) were assessed as having overall high ROB. The quality of evidence for both MoCA and MMSE were deemed to be very low by the GRADE criteria. Results indicated that acupuncture groups may be benefiting more than non-acupuncture groups with respect to variation of MoCA scores (merged mean difference (MMD): 2.66, 95% confidence interval (CI): 2.18 to 3.13, p < 0.00001; heterogeneity: χ2 = 35.52, p = 0.0007, I2 = 63%), and the heterogeneity decreased in both subgroup analysis and sensitivity analysis. In addition, acupuncture groups might be benefiting more than non-acupuncture groups in terms of changes in MMSE score (MMD = 2.97, 95% CI = 2.13 to 3.80, p < 0.00001; heterogeneity: χ2 = 269.75; p < 0.00001; I2 = 92%), and the heterogeneity decreased in subgroup analysis. Only one RCT addressed adverse events, and the symptoms were mild and did not affect treatment and evaluation. CONCLUSION: Acupuncture could be effective and safe for PSCI. Nevertheless, the results should be interpreted cautiously due to the high ROB of included trials and very low quality of evidence for assessed outcomes.


Asunto(s)
Terapia por Acupuntura , Disfunción Cognitiva/terapia , Accidente Cerebrovascular/complicaciones , Anciano , Anciano de 80 o más Años , Ensayos Clínicos como Asunto , Disfunción Cognitiva/etiología , Disfunción Cognitiva/psicología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Accidente Cerebrovascular/psicología , Resultado del Tratamiento
17.
Complement Ther Clin Pract ; 40: 101176, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32347210

RESUMEN

BACKGROUND: Hemiplegia after stroke is one of the main dysfunctions in stroke patients. Acupuncture had been widely used for poststroke spastic hemiplegia (PSSH), but the efficiency was unclear. This study aimed to examine the efficiency and safety of acupuncture for individuals with PSSH. METHODS: We searched nine databases from their inception to 27th July 2019. Randomized controlled trials (RCTs) of acupuncture for the treatment of PSSH met the screening criteria. The quality of methodology was evaluated by Cochrane's risk of bias tool. RevMan 5.3 was used to perform the meta-analysis. The primary outcome was the Fugl-Myer Assessment (FMA) score, and the secondary outcomes were the Ashworth Scale for Spasticity (ASS) and Barthel Index (BI) scores. To evaluated the safety of acupuncture therapy, researchers scanned the full text to collect adverse events. RESULTS: Researchers retrieved 2452 articles in total, after screening, thirty-eight studies with 2628 participants of were included. In this meta-analysis, twenty-seven trials revealed that acupuncture therapy was associated with an increase in FMA scores compared with rehabilitation training (RT) (MD: 8.43, 95% CI, 6.57 to 10.28, p < 0.00001, I2 = 75%). According to the analysis of subgroup of interventions, ten trials showed that manual acupuncture (MA) plus RT was associated with an increase in FMA compared with RT (MD: 10.84, 95% CI, 9.29 to 13.29, p < 0.00001, I2 = 24%), three trials showed that electroacupuncture (EA) plus RT was associated with an improvement in FMA compared with RT (MD: 9.44, 95% CI, 1.00 to 17.88, p = 0.03, I2 = 81%), twelve trials showed that MA was associated with an increase in FMA compared with RT (MD: 5.48, 95% CI, 2.07 to 8.89, p = 0.002, I2 = 74%), and one trials showed that EA was associated with an improvement in FMA compared with RT (MD: 11.35, 95% CI, 5.03 to 17.67, p = 0.0004). According to the analysis of subgroup of treatment duration, four trials used acupuncture therapy for more than 1 month, revealed that acupuncture therapy was associated with an increase in FMA scores compared with RT (MD: 9.24, 95% CI, 0.42 to 18.06, p = 0.04, I2 = 93%). Thirty-two trials used acupuncture therapy for less than or equal to 1 month, revealed that acupuncture therapy was associated with an increase in FMA scores compared with RT (MD: 8.32, 95% CI, 6.56 to 10.09, p < 0.00001, I2 = 61%). Six trials indicated that acupuncture therapy was better than RT in terms of the ASS (MD: 0.46, 95% CI, -0.65 to -0.27, p < 0.00001, I2 = 67%), twenty-four trials indicated that acupuncture therapy was better than RT in terms of the BI scores (MD: 8.32, 95% CI, 5.30 to 11.35, p < 0.00001, I2 = 88%). In general, the methodologies of the RCTs were of poor quality. Two RCTs reported no adverse events, one trial reported five adverse events without severe influence, others did not mention. CONCLUSIONS: This review discovered that acupuncture might be a safe and effective adjuvant therapy for individuals with PSSH. Nevertheless, there were methodological limitations in the included RCTs, and well-designed and large-scale studies should be carried out to confirm our results.


Asunto(s)
Terapia por Acupuntura/métodos , Hemiplejía/terapia , Accidente Cerebrovascular/complicaciones , Electroacupuntura/métodos , Femenino , Humanos , Ensayos Clínicos Controlados Aleatorios como Asunto
18.
Ying Yong Sheng Tai Xue Bao ; 30(5): 1487-1493, 2019 May.
Artículo en Chino | MEDLINE | ID: mdl-31107003

RESUMEN

Seeds are the basis for forest regeneration. To examine the composition and spatio-temporal dynamics of seed rains, a total of 150 seed traps of 0.5 m2 were installed in a 25 hm2 broad-leaved Korean pine (Pinus koraiensis) mixed forest plot in Changbai Mountains. With a total of 252 collections from May 2006 to September 2017, we collected 764299 mature and immature seeds which were belonged to 27 species, 17 genera, and 12 families. More than 90% of all collected seeds (704231 seeds) were from 13 canopy species. Seeds of four tree species, including Tilia amurensis, Fraxinus mandschurica, Acer mono, and Acer pseudo-sieboldianum could be collected every year from each trap. Mast-seeding was found in every canopy layer, but it happened one to two years earlier in the overstorey layer than midstorey and understorey layer. Almost all species produced seeds in autumn, with considerable spatiotemporal variation. Generally, the spatial variation of seeds was larger than temporal variation. Compared with annual variation coefficient of seeds in tropical forest of the Barro Colorado Island (BCI) and subtropical evergreen forest in the Gutianshan, annual variation coefficient of seeds in Changbai Mountains was higher, which supported the hypothesis that annual variation in seed rains would be lower in the tropics than that in higher latitudes.


Asunto(s)
Bosques , Pinus , China , Ecosistema , Semillas , Árboles
19.
Ecol Evol ; 8(15): 7285-7296, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-30151149

RESUMEN

Plant sexual systems appear to play an important role in community assembly: Dioecious species are found to tend to have a higher propensity to colonize communities in early successional stages. Here, we test two demographic hypotheses to explain this pattern in temperate forests. First, we test demographic differences between hermaphrodite and dioecious species in stressful younger successional stages: Previous theory predicts that hermaphrodite seed production is more harmed in stressful environments than that of dioecious populations leading to an advantage for females of dioecious species. Second, in primary forest, we hypothesized that dioecious species would show demographic advantage over monomorphic ones. We used data from two temperate forest plots in Northeast China surveyed over 10 years to compare the rates of growth and mortality of tree species with contrasting breeding systems in both secondary and primary forests. We assessed the effect of breeding system on the growth-mortality trade-off, while controlling for other traits usually considered as correlates of growth and mortality rates. We show that in the secondary forest, dioecious species showed weak advantage in demographic rates compared with monomorphic species; dioecious species showed considerably both lower relative growth and mortality rates compared to the hermaphrodites in the primary forest over 10 years, consistent with a priori predictions. Hermaphrodites showed strong growth-mortality trade-offs across forest stages, even when possibly confounding factors had been accounted for. These results suggest that sexual system influences community succession and assembly by acting on the rates of growth and mortality, and the trade-off between them. As vegetation develops, the demographic differences between breeding systems are much larger. Our results demonstrate the association between breeding system, succession, and community assembly and that this relationship is succession-stage dependent. Our findings support the suggestion that the demographic advantage of dioecious species facilitates the coexistence of sexual systems in primary forest.

20.
Ecol Evol ; 7(14): 5191-5200, 2017 07.
Artículo en Inglés | MEDLINE | ID: mdl-28770059

RESUMEN

Forest community structure may be influenced by seedling density dependence, however, the effect is loosely coupled with population dynamics and diversity in the short term. In the long term the strength of conspecific density dependence may fluctuate over time because of seedling abundance, yet few long-term studies exist. Based on 11 years of seedling census data and tree census data from a 25-ha temperate forest plot in Northeast China, we used generalized linear mixed models to test the relative effects of local neighborhood density and abiotic factors on seedling density and seedling survival. Spatial point pattern analysis was used to determine if spatial patterns of saplings and juveniles, in relation to conspecific adults, were in accordance with patterns uncovered by conspecific negative density dependence at the seedling stage. Our long-term results showed that seedling density was mainly positively affected by conspecific density, suggesting dispersal limitation of seedling development. The probability of seedling survival significantly decreased over 1 year with increasing conspecific density, indicating conspecific negative density dependence in seedling establishment. Although there was variation in conspecific negative density dependence at the seedling stage among species and across years, a dispersed pattern of conspecific saplings relative to conspecific adults at the local scale (<10 m) was observed in four of the 11 species examined. Overall, sapling spatial patterns were consistent with the impacts of conspecific density on seedling dynamics, which suggests that conspecific negative density dependence is persistent over the long term. From the long-term perspective, conspecific density dependence is an important driver of species coexistence in temperate forests.

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