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Yi Zhong

Publications and source records attributed to Yi Zhong.

At least 19 recordsLinked to original sources
PubMed2026

Development and clinical validation of a CRISPR/Cas9-engineered reporter phage cocktail for rapid detection of Escherichia coli in urine.

Urinary tract infections are one of the most common infectious diseases, with Escherichia coli as the predominant pathogen. Traditional diagnostic methods fail to meet clinical demands for rapid and specific detection. Here, we developed an efficient urine E. coli detection strategy via a reporter phage cocktail. Four reporter phages (T2::Nluc, T4::Nluc, T5::Nluc, T6::Nluc) were constructed by the CRISPR/Cas9 system combined with homologous recombination. One-step growth curves, optimal multiplicity of infection, and lytic efficiency showed that the Nluc gene block insertion exerted heterogeneous effects on phages. Luminescence assays demonstrated that all five reporter phages (including previously preserved T7::Nluc) and the cocktail offered favorable limits of detection (≥103 CFU/mL), high specificity, and no urine matrix interference. However, single phages exhibited limited coverage among 177 clinical E. coli isolates. But the reporter phage cocktail remedies this limitation. In large-scale clinical validation, the cocktail achieved sensitivity 73.15% (63.76%-81.22%), specificity 100.00% (99.53%-100.00%), positive predictive value (PPV) 100.00% (95.44%-100.00%), and negative predictive value (NPV) 96.42% (95.18%-97.36%) (all 95% confidence interval [CI]), and excellent concordance with the gold-standard method (Kappa = 0.83, 95% CI: 0.77-0.89), greatly outperforming single reporter phages (~40.00% sensitivity). This method requires no sample pretreatment, is simple to operate, and completes detection within 4 h, significantly improving diagnostic efficiency. Accordingly, it provides a novel platform for pathogen detection and supports the clinical translation of reporter phage diagnostics.IMPORTANCEUrinary tract infections impose substantial economic and public health burdens. In this study, we successfully constructed Escherichia coli-specific reporter phages T2::Nluc, T4::Nluc, T5::Nluc, and T6::Nluc. Combined with the previously preserved T7::Nluc, these phages formed a reporter phage cocktail. Co-cultivation of this cocktail with clinical samples enabled rapid and specific detection of E. coli in clinical urine, with a significantly shortened detection time (4 h) and good concordance with the gold-standard detection method (Kappa = 0.83), effectively improving detection efficiency and accuracy. This novel pathogen detection platform, integrating specific recognition and signal amplification, not only provides a new technical approach for the rapid and accurate diagnosis of clinical urinary tract infections but also effectively promotes the coordinated improvement of infectious disease diagnosis and treatment in terms of timeliness-precision-cost.

Escherichia coli↗
PubMed2025

ABO exon polymorphisms are related to ischemic stroke in a Chinese Han population.

BACKGROUND: Recent research have underscored the relation of ABO blood group system to cerebrovascular disorders predisposition. The present investigation endeavors to delve into the relationship between ABO polymorphisms and ischemic stroke (IS) risk. METHODS: A cohort of 646 IS patients and 649 matched healthy controls was recruited. Genotyping of five SNPs within ABO were conducted by Agena MassARRAY platform. Logistic regression models were employed to estimate odds ratios (ORs) and 95% confidence intervals (CIs). Additionally, SNP-SNP interaction was assessed by multifactor dimensionality reduction (MDR) method. Furthermore, Analysis of Variance (ANOVA) was utilized to explore the association between genotypes and blood lipid profiles. RESULTS: The study identified an elevated IS risk associated with rs8176740 and rs8176720 in the overall population. Notably, ABO rs8176720 emerged as the most informative single-locus model for IS susceptibility. These variants were related to an elevated IS risk, specifically in female subjects, the subgroup aged > 64 years, non-smokers, drinkers or non-drinkers. Moreover, rs8176749 and rs8176745 were associated with red blood cell count levels and total bilirubin levels. CONCLUSION: This study firstly demonstrated the association of ABO rs8176740 and rs8176720 with IS incidence, which increased the understanding regarding the effect of ABO on IS pathogenesis.

Aged↗
PubMed2006

Deletion and single nucleotide substitution at G:C in the kidney of gpt delta transgenic mice after ferric nitrilotriacetate treatment.

An iron chelate, ferric nitrilotriacetate (Fe-NTA), induces oxidative renal proximal tubular damage that subsequently leads to a high incidence of renal cell carcinoma in rodents, presenting an intriguing model of free radical-induced carcinogenesis. In the present study, we used gpt delta transgenic mice, which allow efficient detection of point mutations and deletions in vivo, to evaluate the mutation spectra, in association with the formation of 8-oxoguanine and acrolein-modified adenine during the first 3 weeks of carcinogenesis. Immunohistochemical analysis revealed the highest levels of 8-oxoguanine and acrolein-modifed adenine in the renal proximal tubules after 1 week of repeated administration. DNA immunoprecipitation and quantitative polymerase chain reaction analysis showed that the relative abundance of 8-oxoguanine and acrolein-modified adenine at the gpt reporter gene were increased at the first week in the kidney. Similarly, in both 6-thioguanine and Spi(-) selections performed on the renal specimens after Fe-NTA administration, the mutant frequencies were increased in the Fe-NTA-treated mice at the first week. Further analyzes of 79 mutant clones and 93 positive plaques showed a high frequency of G:C pairs as preferred targets for point mutation, notably G:C to C:G transversion-type mutation followed by deletion, and of large-size (>1 kilobase) deletions with short homologous sequences in proximity to repeated sequences at the junctions. The results demonstrate that the iron-based Fenton reaction is mutagenic in vivo in the renal tubular cells and induces characteristic mutations.

Animals↗
PubMed2006

Requirement of Akt to mediate long-term synaptic depression in Drosophila.

Drosophila larval neuromuscular junction (NMJ) is a well established preparation enabling quantitative analyses of synaptic physiology at identifiable synapses. Here, we report the first characterization of synaptic long-term depression (LTD) at the Drosophila NMJ. LTD can be reliably induced by specific patterns of tetanic stimulation, and the level of LTD depends on both stimulus frequency and Ca2+ concentration. We provide evidence that LTD is likely a result of presynaptic changes. Through screening of targeted mutants with defects in memory or signal transduction pathways, we found that LTD is strongly reduced in the akt mutants. This defect can be rescued by acutely induced expression of the normal akt transgene, suggesting that altered LTD is not attributable to developmental abnormalities and that Akt is critical for the induction of LTD. Our study also indicates that the molecular mechanisms of LTD are distinct from that of short-term synaptic plasticity, because akt mutants showed normal short-term facilitation and posttetanic potentiation, whereas LTD was unaffected in mutants that exhibit defective short-term synaptic plasticity, such as dunce and rutabaga. The characterization of LTD allows genetic analysis of the molecular mechanisms of long-term synaptic plasticity in Drosophila and provides an additional assay for studying functions of genes pertaining to synaptic and behavioral plasticity.

Animals↗
PubMed2006

Effect of neurofibromatosis type I mutations on a novel pathway for adenylyl cyclase activation requiring neurofibromin and Ras.

Neurofibromatosis type I (NFI) is a common genetic disorder that causes nervous system tumors, and learning and memory defects in humans, and animal models. We identify a novel growth factor stimulated adenylyl cyclase (AC) pathway in the Drosophila brain, which is disrupted by mutations in the epidermal growth factor receptor (EGFR), neurofibromin (NF1) and Ras, but not Galpha(s). This is the first demonstration in a metazoan that a receptor tyrosine kinase (RTK) pathway, acting independently of the heterotrimeric G-protein subunit Galpha(s), can activate AC. We also show that Galpha(s) is the major Galpha isoform in fly brains, and define a second AC pathway stimulated by serotonin and histamine requiring NF1 and Galpha(s), as well as a third, classical Galpha(s)-dependent AC pathway, which is stimulated by Phe-Met-Arg-Phe-amide (FMRFamide) and dopamine. Using mutations and deletions of the human NF1 protein (hNF1) expressed in Nf1 mutant flies, we show that Ras activation by hNF1 is essential for growth factor stimulation of AC activity. Further, we demonstrate that sequences in the C-terminal region of hNF1 are sufficient for NF1/Galpha(s)-dependent neurotransmitter stimulated AC activity, and for rescue of body size defects in Nf1 mutant flies.

Adenylyl Cyclases↗
PubMed2006

[Clinical observation on liang's anti-rheumatism and rheumatoid granule in rheumatoid arthritis in the active stage].

OBJECTIVE: To evaluate the therapeutic effect of Liang's anti-rheumatism and rheumatoid granule (LARG) in treating patients with rheumatoid arthritis (RA) at the active stage. METHODS: Fifty patients were administered orally with LARG in the treated group, 30 patients were treated with Wangbi granule in the control group. Symptoms, physical signs and relevant laboratory indexes in the 2 groups were observed and compared before treatment and after being treated for 2 months. RESULTS: The total effective rate and curative-markedly effective rate in the treated groups were superior to those in the control group (P <0.01). The improvement in aspects of integral scoring of symptom and physical signs, including arthragia, tumefaction, dysfunction indexes, morning stiffness and 15m walking time, and laboratory indexes, including blood sedimentation rate, rheumatoid factor, C creative protein, immunoglobin, as well as hemorheology relevant indexes in the treated group after treatment were significantly different to those before treatment and those in the control group (P <0.05 or P <0.01). CONCLUSION: LARG has obvious therapeutic effect on RA at the active stage.

Adult↗
PubMed2005

Transcriptional control of fetal liver hematopoiesis: dominant negative effect of the overexpression of the LIM domain mutants of LMO2.

OBJECTIVE: The LIM-finger protein LMO2 forms a transcription factor complex with other hematopoietic regulator proteins, such as TAL1 (SCL), LDB1, GATA1, 2, and 3, in the promoters of several erythroid genes. To elucidate the functional role of two LIM domains in LMO2, we introduced deletion or mutation in each of the LIM domains and analyzed their phenotypic effects on the hematopoietic system when overexpressed in vivo or in vitro. MATERIALS AND METHODS: Protein interactions of LIM-modified LMO2 constructs with TAL1, LDB1, and GATAs were examined in an immunoprecipitation assay. In vivo hematopoiesis in transgenic mice with wild-type and LIM-modified Lmo2 was studied morphologically and by measuring the progenitor cells in fetal liver. Their effects on the erythroid differentiation of the dimethylsulfoxide (DMSO)-induced murine erythroleukemia (MEL) cells were evaluated. RESULTS: Deletion of the LIM2 domain, but not of the LIM1 domain, abolished its binding of GATA proteins. Overexpression of wild-type LMO2 is known to have dominant negative inhibitory effects on erythropoietic development. Enforced expression of LMO2 constructs with mutant or absent LIM2 but with an intact LIM1 domain resulted in fetal death, small livers and hearts, and decreased hematopoiesis, as well as a hypoplastic thymus. DMSO-induced erythroid differentiation of the MEL cells was inhibited by the overexpressed LMO2 with mutant LIM2 but not by the LMO2 with modified LIM1. CONCLUSION: Overexpression of the LMO2 with modified LIM2 inhibited hematopoiesis probably by interfering with the formation of the physiological complex or by replacing the functional LMO2 with mutants with reduced affinity to GATA proteins. In this experiment, no evident effect of the LMO2 with modified LIM1 could be observed.

Adaptor Proteins, Signal Transducing↗
PubMed2005

[Clinical observation on effect of weichangshu in treating diabetic gastroparesis].

OBJECTIVE: To observe the effect of Weichangshu (WCS) in treating diabetic gastroparesis (DGP). METHODS: Ninety-six patients with DGP were randomly divided into two groups. Besides the same conventional blood glucose controlling regimen was given to both groups, WSC was given to the treated group and Mosapride Citrate tablet to the control group additionally. The treatment course for them was 4 weeks. Therapeutic effect on clinical syndromes was assessed, the fasting and 2-hr postprandial blood glucose, antro-duodenal interdigestive migrating motor complex (MMC) and electrogastrogram (EGG) were measured before and after treatment. RESULTS: The therapeutic effect in the two groups were similar with no statistical significant difference. The time of MMC phase II was shortened, time of MMC phase III prolonged, and the constriction amplitude of which increased after treatment in both groups, showing significant difference as compared to those before treatment (P < 0.05). EGG were significantly changed after treatment mainly manifested as increase of proportional dominant frequency (PDF) and strengthening of proportional dominant amplitude (PDP ) (P <0.05 or P < 0.01). Besides, WSC also promoted the decrease of post-prandial blood glucose. CONCLUSION: WSC has dual effect in promoting gastric motility and decreasing blood glucose, with less adoerst reaction.

Adult↗
PubMed2005

[Effects of acid soils on the biodegradation of hydrocarbons].

Biodegradation efficiency of hydrocarbons and melioration of micro-ecosystem conditions in acid soils should be seriously concerned due to either occurrence of acid polluted soils or acidification during bioremediation process. The influence of acid situation on degrading microbes and the biodegradation rate were figured out by monitoring variations of biomass, microbial activities and petroleum contents with time in acid and alkaline polluted soils in laboratory. Injecting degrading microbes and meliorating micro-ecosystem conditions of acid soils were conducted. The results showed that acid soils (pH = 5.4-5.7) had extreme restraint on local microbe numbers and activities, and biodegradation rate almost reached zero. Injection of degrading microbes could not remarkably reduce the restriction of acid conditions. The microbe numbers quickly went down from 10(6) cells/g dried soil to zero in 14 days and the Fluorescein Diacetate (FDA) activities were only about 0.10 Abs/g dried soil. However, addition of bio-carriers could effectively improve micro-ecosystem conditions in acid soils, thus notably diminish the restraint to some extent. In 19 days, the amount of microorganisms decreased from 2 x 10(6) to 2.2 x 10(2) cells/g dried soil. And up to 49 days, about 13% hydrocarbons were removed from the polluted soils by microbes.

Acids↗
PubMed2005

[Clinical observation on jiangni hewei decoction in treatment of 45 patients with reflux esophagitis].

OBJECTIVE: To observe the therapeutic efficacy of Jiangni Hewei Decoction (JHD) in treating reflux esophagitis (RE). METHODS: Seventy-five RE patients conformed with the inclusive criteria were randomly divided into the treated group (45 patients) and the control group (30 patients). Patients in the treated group received JHD orally, one dose per day, while those in the control group received Omeprazole, 20 mg once per day. The therapeutic course was 8 weeks. The efficacy on clinical symptoms, RE grades and scores determined by gastroscope were evaluated. RESULTS: Patients' symptoms were obviously improved after treatment of JHD and Omeprazole. The cured rate and the total effective rate in the treatedgroup were 37.8% (17 cases) and 84.5%, respectively, while in the control group were 36.7% (11 cases) and 83.3% respectively. The symptomatic score and the total score in both groups after treatment were obviously lowered (P < 0.01). Gastroscopic examination showed that the patients in the two groups with RE of 0 grade were significantly increased and no patients with RE of III grade. The healing rate and the total effective rate were 48.9% (22 cases) and 91.1% respectively in the treated group, and the corresponding numbers in the control group were 46.7% (14 cases) and 93.3% respectively. Significant difference was found in comparison of the gastroscopic figures in the same group before and after treatment (P < 0.01). The therapeutic effect of JHD on RE was similar to that of Omeprazole in aspects of improving clinical symptoms such as heartburn, acid regurgitation, chest pain, etc., and in curing oesophageal mucous inflammation (under gastroscope) and esophagitis. But the recurrence in the JHD group was obviously lower than that in the control group in 12 weeks after withdrawal of treatment (P < 0.05). Besides, no adverse reaction happened in the JHD group. CONCLUSION: JHD showed favorable therapeutic efficacy in treating RE.

Adult↗
PubMed2004

Stereotyped odor-evoked activity in the mushroom body of Drosophila revealed by green fluorescent protein-based Ca2+ imaging.

To study the representation of olfactory information in higher brain centers, we expressed a green fluorescent protein-based Ca2+ sensor, G-CaMP, in the Drosophila mushroom body (MB). Using two-photon microscopy, we imaged odor-evoked G-CaMP fluorescence transients in MB neurons [Kenyon cells (KCs)] with single-cell resolution. Odors produced large fluorescence transients in a subset of KC somata and in restricted regions of the calyx, the neuropil of the MB. In different KCs, odor-evoked fluorescence transients showed diverse changes with odor concentration: in some KCs, fluorescence transients were evoked by an odor at concentrations spanning several orders of magnitude, whereas in others only at a narrow concentration range. Different odors produced fluorescence transients in different subsets of KCs. The spatial distributions of KCs showing fluorescence transients evoked by a given odor were similar across individuals. For some odors, individual KCs with fluorescence transients evoked by a particular odor could be found in similar locations in different flies with spatial precisions on the order of the size of KC somata. These results indicate that odor-evoked activity can have remarkable spatial specificity in the MB.

Animals↗
PubMed2004

Notch signaling in Drosophila long-term memory formation.

Notch (N) is a cell surface receptor that mediates an evolutionarily ancient signaling pathway to control an extraordinarily broad spectrum of cell fates and developmental processes. To gain insights into the functions of N signaling in the adult brain, we examined the involvement of N in Drosophila olfactory learning and memory. Long-term memory (LTM) was disrupted by blocking N signaling in conditional mutants or by acutely induced expression of a dominant-negative N transgene. In contrast, neither learning nor early memory were affected. Furthermore, induced overexpression of a wild-type (normal) N transgene specifically enhanced LTM formation. These experiments demonstrate that N signaling contributes to LTM formation in the Drosophila adult brain.

Animals↗
PubMed2004

Dissecting the pathological effects of human Abeta40 and Abeta42 in Drosophila: a potential model for Alzheimer's disease.

Accumulation of amyloid-beta (Abeta) peptides in the brain has been suggested to be the primary event in sequential progression of Alzheimer's disease (AD). Here, we use Drosophila to examine whether expression of either the human Abeta40 or Abeta42 peptide in the Drosophila brain can induce pathological phenotypes resembling AD. The expression of Abeta42 led to the formation of diffused amyloid deposits, age-dependent learning defects, and extensive neurodegeneration. In contrast, expression of Abeta40 caused only age-dependent learning defects but did not lead to the formation of amyloid deposits or neurodegeneration. These results strongly suggest that accumulation of Abeta42 in the brain is sufficient to cause behavioral deficits and neurodegeneration. Moreover, Drosophila may serve as a model for facilitating the understanding of molecular mechanisms underlying Abeta toxicity and the discovery of novel therapeutic targets for AD.

Aging↗
PubMed2004

TARGETing "when" and "where".

In Drosophila, the cyclic adenosine monophosphate (cAMP) pathway has been shown to be crucial for learning and memory, but whether this represents a developmental or a specific effect has not been resolved. Research with a new targeting system that allows both spatial and temporal control of gene expression shows that expression of rutabaga-encoded adenylyl cyclase, a component of the cAMP signaling pathway, in the mushroom bodies of adult flies is necessary and sufficient to rescue the learning defect of rutabaga mutant. This demonstrates an acute role for Rutabaga in learning and memory.

Animals↗
PubMed2004

Neuronal activity and adenylyl cyclase in environment-dependent plasticity of axonal outgrowth in Drosophila.

The development of the nervous system is influenced by environmental factors. Among all environmental factors, temperature belongs to a unique category. Besides activating some specific sensory pathways, it exerts nonspecific, pervasive effects directly on the entire nervous system, especially in exothermic species. This study uses mutants to genetically discover how temperature affects nerve terminal arborization at larval neuromuscular junctions of Drosophila. It is known that hyperexcitability in K(+) channel mutants leads to enhanced ramification of larval nerve terminals. Elevated cAMP levels in dunce mutants with reduced phosphodiesterase activity also cause enhanced arborization. These genetic alterations are thought to perturb mechanisms relevant to activity-dependent neural plasticity, in which neuronal activity activates the cAMP pathway, and consequently affect nerve terminal arborization by regulating expression of adhesion molecules. Here we demonstrate the robust influence of rearing temperature on motor nerve terminal arborization. Analysis of ion channel and cAMP pathway mutants indicates that this temperature-dependent plasticity is mediated via neuronal activity changes linked to mechanisms controlled by the rutabaga-encoded adenylyl cyclase.

Adenylyl Cyclases↗
PubMed2004

[The relationship between abiotic factors and microbial activities of microbial eco-system in contaminated soil with petroleum hydrocarbons].

By means of the biostimulation and bioaugmentation in the micro-ecological environment of contaminated soil with petrochemical hydrocarbons, the biodegradation rates and mode of the contaminants were significantly improved. Based on the investigations carried out in some oilfields and petrochemical industrial area of Northern China, the relationship between the abiotic factors such as nutrient, pH, contaminants, water content, alkalinity, etc., and microbial activities was interpreted and identified in this paper. The results from the investigations and indoor and in-situ experiments conducted recent years indicated that the soils in the areas, to the extent, have been polluted by the different kinds of organic compounds composed of monoaromatic benzene, PAHs, chlorinated solvent, and alkanes, and the concentrations of the compounds mostly were elevated as compared to the background, with the highest 34,000 mg/kg dry soil. The column chromatography analysis results showed that the alkyl and aromatic compounds were accounted for more than 50% of the total hydrocarbon contents, which was readily degraded by degrading bacteria and improved the degrading microbe activities. The effective nitrogen and phosphorus encountered in the soil was less than 30 mg/kg dry soil and 10 mg/kg dry soil, only about 5% of total contents of them respectively. Based on the stoichiometric calculation and reasonable ratio of carbon to nutrient content regarding the biodegradation of organic compounds, the nutrient levels mainly composed of nitrogen and phosphorus in polluted soil as importantly limiting factors to degrading bacterial growth and activity were insufficient to the biodegradation of petrochemicals, and it is needed to add the nutrient for the bioremediation of contaminated soil. It is undoubted that the optimization of abiotic factors play significant role in increasing the microbial activity and improving the biodegradation rates.

Biodegradation, Environmental↗
PubMed2003

Blockade of neurotransmission in Drosophila mushroom bodies impairs odor attraction, but not repulsion.

Olfaction can elicit a rich perceptual experience. It is not known, however, whether olfactory information is decomposed into various components and processed in distinct perceptual centers as in other sensory systems, such as vision, where neural representations of different visual sensations are segregated in different cortical regions, despite the fact that multiple structures of the primary olfactory cortex receive projections from the olfactory bulb. Here, we use Drosophila as a model to investigate whether different olfactory information may be processed in separate brain structures. Organizations of the peripheral olfactory system are remarkably similar from mammals to insects. As in vertebrates, the olfactory pathway in Drosophila follows similar convergence and divergence, and multiple high-order structures in the Drosophila brain, including the mushroom body (MB) and lateral horn (LH) of the protocerebrum, receive olfactory input. We specifically blocked neurotransmission in the MB while leaving the LH unaffected and examined its effect on olfactory avoidance and attraction behaviors. We show that blocking MB activity disrupted responses to attractive, but not repulsive, odors, and this finding suggests that attractive and repulsive olfactory information may be separately processed in higher olfactory centers of the Drosophila brain.

Animals↗