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1.
Artigo em Inglês | MEDLINE | ID: mdl-32087278

RESUMO

Virulent pathogenic microorganisms often enhance their infectivity through immune evasion mechanisms. Our research on the integrative and conjugative element (ICE(r2)) of the virulent fish pathogen Yersinia ruckeri SC09 led to the identification of genes related to immune evasion (designated stir-1, stir-2, stir-3 and stir-4), among which stir-1 and stir-2 were determined as the key contributors to bacterial toxicity and immune evasion. Here, we further examined the ability of stir-3 to mediate immune evasion based on detailed bioinformatic analysis of ICE(r2) from Y. ruckeri SC09. Interactions among the translated STIR-1, STIR-2, STIR-3 and STIR-4 proteins in the secretory process were additionally explored. STIR-3 was positively correlated with bacterial toxicity and inhibited host toll-like receptor (TLR) signaling by interacting with MyD88, thereby facilitating bacterial survival in host cells. Importantly, our data showed co-secretion of STIR-1, STIR-2 and STIR-3 as a complex, with secretion failure occurring in the absence of any one of these proteins. While stir-1, stir-2, stir-3 and stir-4 genes werespecific to Y. ruckeri SC09, the ICE(r2) region where these genes were located is a mobile component widely distributed in bacteria. Therefore, the potential transmission risk of these immune evasion genes requires further research attention.

2.
Fish Physiol Biochem ; 2020 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-32016779

RESUMO

Cadmium (Cd), a substance with one of the most critical health hazard indices, can cause damage to both the blood and kidneys and accumulates in the body at last. The present work studied the toxicological effects of Cd and the therapeutic effects of metallothionein (MT) and vitamin E (VE) on the trunk kidney and blood of freshwater grass carp (Ctenopharyngodon idellus). Grass carp were divided into three groups: Cd + phosphate-buffered saline (PBS) group, Cd + VE group, and the Cd + MT group. Fish were injected with CdCl2 on the first day and then VE, MT, or PBS was administered 4 days post-injection. Fish not injected with Cd were used as a negative control. The blood and trunk kidney amassed Cd and suffered severe damage in the forms of organ toxicity cytotoxicity, and immunotoxicity. However, the MT reduced the Cd content in the trunk kidney and blood and partially stabilized the damaged organs. Treatment with VE, however, only demonstrated weaker protection against on Cd-induced toxicity. The results indicate that exogenous MT may play an essential role in restoring homeostasis of the Cd-poisoned urinary and circulatory system and that it may help eliminate Cd in aquatic animals.

3.
Transbound Emerg Dis ; 2020 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-31904194

RESUMO

Ranaviruses are important emerging pathogens of ectothermic vertebrates that threaten aquaculture and wildlife worldwide. A mortality event occurred in a cultured population of catfish-like loach (Triplophysa siluorides) in Sichuan Province, China. Gross clinical signs of the affected fish included skin lesions and haemorrhagic ulcers, which are often associated with ranaviruses. Inoculation of liver, kidney and spleen tissue homogenates in epithelioma papulosum cyprini (EPC) cells at 25°C resulted in cytopathic effect within 24 hr. Transmission electron microscopy of infected EPC cells revealed hexagonal viral arrays in the cytoplasm and icosahedral geometry of the virions. Following exposure of T. siluroides to the isolated virus, similar clinical signs were observed and the fish experienced 40% and 90% mortality after 21 days at 103.58 and 107.8 TCID50 /0.1 ml doses, respectively, providing evidence the isolated virus was the main causative agent of the mortality event. Diagnostic PCR of the major capsid protein gene of ranavirus showed that all samples of diseased fish and isolated virus were positive. Phylogenetic analysis revealed that the isolated virus, designated as FYLl40220, was associated with the Common Midwife Toad Virus (CMTV)-like ranavirus clade. To our knowledge, this case represents the first report of CMTV-associated mortality in a fish species. Collectively, these results suggest that the host range of CMTV-like ranaviruses is greater than previously thought, and this clade of ranaviruses could have significant economic and biodiversity impacts.

4.
Virulence ; 11(1): 23-31, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31826705

RESUMO

Vibrio mimicus is a foodborne pathogen, which is widely distributed in the aquatic environment. Moreover, it is often involved in aquatic animal diseases. In recent years, V. mimicus is an emerging pathogen in some species of Siluriformes. The strain SCCF01 was isolated from yellow catfish (Pelteobagrus fulvidraco). In this study, we aimed to perform genomic analysis of V. mimicus strain SCCF01 to identify genetic features and evolutionary relationships. Information on gene function and classification was obtained by functional annotation, and circular graph of strain SCCF01 genome, which was created by Circos v0.64. Information on virulence genes (adhesion, flagellum system, exotoxin, and secretory system, etc.) was obtained by virulence genes annotation. Genome element prediction showed that most of the mobile elements were distributed in chromosome I. Therefore, chromosome I of SCCF01 genome has more plasticity than chromosome II and might be larger in size. Genomic linear relationship between the strain of V. mimicus and strain SCCF01 was analyzed by linear pairwise comparison but was unable to determine the relationship. Gene family analysis predicted that the evolutionary direction of strain SCCF01 was: clinical strain → environmental strain → SCCF01 strain. Phylogenetic analysis showed that the strain SCCF01 was more closely related to environmental strains. According to gene family analysis and phylogenetic analysis, we speculated that strain SCCF01 has probably diverged from environmental strains.

5.
Abdom Radiol (NY) ; 45(1): 73-82, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31372777

RESUMO

OBJECTIVE: To compare the ability of MR elastography (MRE) with transient elastography (TE) and intravoxel incoherent motion (IVIM) diffusion-weighted MRI in staging hepatic fibrosis (HF). MATERIALS AND METHODS: 100 patients with chronic liver disease and 25 healthy volunteers underwent preoperative MRE, IVIM on a 3T MRI unit, and ultrasound-based TE. Liver stiffness measurement from MRE (LSM-MRE) and liver stiffness measurement from TE (LSM-TE) were measured; four diffusion parameters including the true diffusion coefficient (Dt), pseudo-diffusion coefficient, perfusion fraction (f), and apparent diffusion coefficient (ADC) were calculated. Receiver operating characteristic (ROC) curves were performed for significant parameters to compare the diagnosis performance for detecting HF. RESULTS: LSM-MRE and LSM-TE values showed positive correlation with the fibrosis stage (r = 0.910 and 0.813, P < 0.001). Dt, f, and ADC values showed negative correlation with the fibrosis stage (r = - 0.727, - 0.503, and - 0.601, all P < 0.001). The area under the ROC curve (AUC) of LSM-MRE (AUC = 0.965, 0.957, 0.983) was significantly higher than that of LSM-TE (AUC = 0.906, 0.913, 0.931) and Dt (AUC = 0.875, 0.879, 0.861) in discriminating significant HF (≥ F2), advanced HF (≥ F3), or cirrhosis (F4) (all P < 0.05). Although LSM-TE showed higher AUCs than Dt in detecting fibrosis stages, there were no significant differences between LSM-TE and Dt (P > 0.05) except for detecting F4 (P < 0.05). CONCLUSION: MRE shows excellent diagnostic performance for predicting significant fibrosis, advanced fibrosis compared with TE and IVIM, while TE and IVIM have comparable diagnostic performance.

6.
Curr Biol ; 29(24): 4337-4344.e5, 2019 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-31813606

RESUMO

External cues, including touch, enable walking animals to flexibly maneuver around obstacles and extricate themselves from dead-ends (for reviews, see [1-3]). In a screen for neurons that enable Drosophila melanogaster to retreat when it encounters a dead-end, we identified a pair of ascending neurons, the TwoLumps Ascending (TLA) neurons. Silencing TLA activity impairs backward locomotion, whereas optogenetic activation triggers backward walking. TLA-induced reversal is mediated in part by the Moonwalker Descending Neurons (MDNs) [4], which receive excitatory input from the TLAs. Silencing the TLAs decreases the extent to which freely walking flies back up upon encountering a physical barrier in the dark, and TLAs show calcium responses to optogenetic activation of neurons expressing the mechanosensory channel NOMPC. We infer that TLAs convey feedforward mechanosensory stimuli to transiently activate MDNs in response to anterior body touch.

7.
Sci Rep ; 9(1): 20014, 2019 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-31882981

RESUMO

Thelohanellus kitauei is a spore-forming myxosporean parasite prevalent in scattered mirror carp (Cyprinus carpio) that generates numerous cysts in the intestine and causes mass mortality in fish. To investigate the infection and mortality induced by T. kitauei in pond-reared farms in Luo-Jiang (104°51'N, 31°31'E), southwest China, morphological and molecular analyses of infected fish were conducted. Natural and specific immune indicators were further evaluated to determine the immunological effects of response to parasitic infection. The infectious parasite was identified as Thelohanellus kitauei based on morphological, 18S rDNA and infectious characteristics. Scattered mirror carp was determined as the specific intermediate host of the parasite. However, T. kitauei still caused considerable damage to the fish, in particular, injury and blockage of the intestines, resulting in malnutrition and even death. The mature spores of T. kitauei colonize the intestinal submucosa of carp and form cysts of various sizes that block the intestinal tract and release spores into the enteric cavity upon rupture, leading to the next phase of T. kitauei growth. Moreover, T. kitauei-infected carp showed weaker innate immunity. IgM is involved in the fight against parasitic infection while cytokines, such as IL-6, IL-1ß and TNF-α, had an impact on infection processes. To our knowledge, this is the first report to show that T. kitauei infects and causes death in scattered mirror carp. Our collective findings from systematic pathology, morphology and immunology experiments provide a foundation for further research on infections by this type of parasite and development of effective treatment strategies.

8.
Colloids Surf B Biointerfaces ; 188: 110755, 2019 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-31887646

RESUMO

Natural cellular membranes, with the outstanding qualities of biocompatibility and specificity, have gained growing attentions in the system of drug delivery. Nanoparticles coated with cellular membranes are starting to be applied as drug-loaded-vehicles to target tumors. Here, neutrophil membranes were selected to apply in the treatment of inflammation because neutrophils can participate in various inflammatory responses and accumulate at inflammatory sites to eliminate pathogens. Through extracting neutrophil membranes from natural neutrophils without affecting their biological properties, nanoparticles loaded with sparfloxacin (SPX) were coated with these membranes and disguised as neutrophils. Compared with traditional nano-medicines, the neutrophil membrane-coated nanoparticles (NM-NP-SPX) possessed precise targeting ability just like the neutrophils could accumulate at inflammatory sites when inflammation burst. In addition, NM-NP-SPX could prolong the circulation time and had the property of controlled-release. Through in vivo experiments, we found that the concentration of three representative inflammatory cytokines in blood, bacteria and inflammatory cells in lungs of the mice with pneumonia reduced significantly in the initial 24 h after the injection of NM-NP-SPX, which meant that NM-NP-SPX could greatly reduce the risk of death for the patients with inflammation. Moreover, the infected lungs could recover rapidly without any side effects to other organs due to the low cytotoxicity of NM-NP-SPX against normal cells. Therefore, our developed drug delivery system has enormous advantages in treating inflammations. Not only that, this kind of bionic method may have greater value and application prospects in curing the inflammations arisen from cancers.

9.
Oxid Med Cell Longev ; 2019: 6407524, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31641424

RESUMO

Most species of the genus Elizabethkingia are pathogenic to humans and animals, most commonly causing meningitis. However, our understanding of the pathogenic mechanisms involved is poor and there have been few pathological studies of Elizabethkingia spp. in animals. To understand the host injury induced by Elizabethkingia spp., we established a model of E. miricola infection in the black-spotted frog (Pelophylax nigromaculatus). The systematic pathology in and oxidative damage in the infection model were investigated. Our results show that recently isolated E. miricola is a bacterium that mainly parasitizes the host brain and that neurogenic organs are the predominant sites of damage. Infection mainly manifested as severe brain abscesses, meningoencephalitis, necrotic spondylitis, and necrotic retinitis. The liver, spleen, kidney, gastrointestinal tract, and lung were also affected to varying degrees, with bacterial necrotic inflammation. P. nigromaculatus also suffered enormous damage to its oxidative system during E. miricola infection, which may have further aggravated its disease state. Our results provide a preliminary reference for the study and treatment of Elizabethkingia spp.-induced neurological diseases in animals.

10.
Medicine (Baltimore) ; 98(39): e17130, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31574813

RESUMO

Animal studies have demonstrated that autophagy was involved in neuronal damage after intracerebral hemorrhage (ICH). Several studies showed thrombin-antithrombin (TAT) plasma levels were elevated in patients with ICH. In this study, we aimed to evaluate if autophagy occurred in patients with ICH; and the relationship between the severity of brain injury and plasma TAT levels.A novel tissue harvesting device was used during hematoma removal surgery to collect loose fragments of tissue surrounding the affected brain area in 27 ICH patients with hematoma volumes of >30 mL in the basal ganglia. Control tissues were obtained from patients who underwent surgery for arteriovenous malformation (n = 25). Transmission electron microscopy (TEM) and immunohistochemistry for autophagy-related proteins were used to evaluate the ultrastructural and morphologic cellular characteristics; and the extent of autophagy in the recovered tissue specimens. Stroke severity was assessed by using the Glasgow Coma Scale (GCS) and the National Institutes of Health Stroke Scale (NIHSS). An enzyme-linked immunosorbent assay (ELISA) was used to measure plasma TAT levels.Transmission electron microscopy showed autophagosomes and autolysosomes exist in neurons surrounding the hematoma, but not in the control tissues. The number of cells containing autophagic vacuoles correlated with the severity of brain injury. Immunohistochemistry showed strong LC3, beclin 1, and cathepsin D staining in ICH tissue specimens. Plasma TAT levels correlated positively with autophagic cells and ICH severity (P < .01).Autophagy was induced in perihematomal neurons after ICH. Autophagy and plasma TAT levels correlated positively with severity of brain injury. These results suggest that autophagy and increased plasma TAT levels may contribute to the secondary damage in ICH patients.


Assuntos
Autofagia , Hemorragia Cerebral/sangue , Hematoma/sangue , Neurônios/fisiologia , Peptídeo Hidrolases/sangue , Adulto , Idoso , Antitrombina III , Gânglios da Base/metabolismo , Hemorragia Cerebral/fisiopatologia , Hemorragia Cerebral/cirurgia , Feminino , Escala de Coma de Glasgow , Hematoma/fisiopatologia , Hematoma/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade
11.
Microb Pathog ; 137: 103748, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31521802

RESUMO

Salmonellosis is a serious threat to human and animal health. Salmonella adhesion to the host cell is an initial and most crucial step in the pathogenesis of salmonellosis. Many factors are involved in the adhesion process of Salmonella infection. Fimbriae are one of the most important factors in the adhesion of Salmonella. The Salmonella fimbriae are assembled in three types of assembly pathways: chaperon-usher, nucleation-precipitation, and type IV fimbriae. These assembly pathways lead to multiple types of fimbriae. Salmonella fimbriae bind to host cell receptors to initiate adhesion. So far, many receptors have been identified, such as Toll-like receptors. However, several receptors that may be involved in the adhesive mechanism of Salmonella fimbriae are still un-identified. This review aimed to summarize the types of Salmonella fimbriae produced by different assembly pathways and their role in adhesion. It also enlisted previously discovered receptors involved in adhesion. This review might help readers to develop a comprehensive understanding of Salmonella fimbriae, their role in adhesion, and recently developed strategies to counter Salmonella infection.

12.
Int J Mol Sci ; 20(18)2019 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-31500298

RESUMO

TIR domain-containing proteins are essential for bacterial pathogens to subvert host defenses. This study describes a fish pathogen, Yersinia ruckeri SC09 strain, with a novel TIR domain-containing protein (STIR-2) that affects Toll-like receptor (TLR) function. STIR-2 was identified in Y. ruckeri by bioinformatics analysis. The toxic effects of this gene on fish were determined by in vivo challenge experiments in knockout mutants and complement mutants of the stir-2 gene. In vitro, STIR-2 downregulated the expression and secretion of IL-6, IL-1ß, and TNF-α. Furthermore, the results of NF-κB-dependent luciferase reporter system, co-immunoprecipitation, GST pull-down assays, and yeast two-hybrid assay indicated that STIR-2 inhibited the TLR signaling pathway by interacting with myeloid differentiation factor 88 (MyD88). In addition, STIR-2 promoted the intracellular survival of pathogenic Yersinia ruckeri SC09 strain by binding to the TIR adaptor protein MyD88 and inhibiting the pre-inflammatory signal of immune cells. These results showed that STIR-2 increased virulence in Y. ruckeri and suppressed the innate immune response by inhibiting TLR and MyD88-mediated signaling, serving as a novel strategy for innate immune evasion.


Assuntos
Proteínas Adaptadoras de Transporte Vesicular/genética , Doenças dos Peixes/microbiologia , Fator 88 de Diferenciação Mieloide/metabolismo , Yersiniose/veterinária , Yersinia ruckeri/patogenicidade , Proteínas Adaptadoras de Transporte Vesicular/imunologia , Animais , Aderência Bacteriana , Proteínas de Bactérias/genética , Proteínas de Bactérias/imunologia , Doenças dos Peixes/imunologia , Proteínas de Peixes/metabolismo , Regulação da Expressão Gênica , Evasão da Resposta Imune , Camundongos Knockout , Oncorhynchus mykiss , Domínios Proteicos , Transdução de Sinais , Receptores Toll-Like/metabolismo , Fatores de Virulência/genética , Fatores de Virulência/imunologia , Yersiniose/imunologia , Yersinia ruckeri/genética , Yersinia ruckeri/imunologia
13.
BMC Med Genomics ; 12(1): 126, 2019 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-31481113

RESUMO

BACKGROUND: Indigenous typhoid fever was continuing to be identified in Taiwan which has not been endemic for the enteric fever for more than 20 years. The source and transmission by which the local patients acquired typhoid and the population structure of the indigenous typhoid strains remain not well characterized. METHODS: During 2001 and 2014, non-duplicated clinical Salmonella enterica serovar Typhi isolates in a hospital were analyzed by whole-genome sequencing (WGS) and determined for pulsotypes. Maximum likelihood phylogeny was constructed by nucleotide alterations in core genomes and compared to the framework of global typhoid strains. Potential source and transmission were traced by correlating the phylogeny and the temporal relationship between isolates. RESULTS: A total of 43 S. Typhi isolates from indigenous cases were analyzed and a majority (39, 90.7%) of them were belonged to six WGS-defined genotypes prevailing mainly in Southeast Asia. Genotype 3.4.0 and a multidrug-resistant type 4.3.1 (also known as pandemic H58 haplotype) were associated respectively with two solitary small-scale outbreaks, implying a transmission mode of importation followed by outbreak. Twelve isolates with nearly identical core genomes were belonged to genotype 3.2.1 but were categorized into three different pulsotypes. The 3.2.1 isolates were identified across 13 years and involved in three clusters and a sporadic case, indicating sustained local transmission of the same strain. The remaining indigenous isolates belonging to three genotypes (2.1, 3.1.2, and 3.0.0) were of substantial genetic diversity and isolated at different time points, indicating independent event of each case. CONCLUSIONS: Indigenous typhoid in Taiwan occurred mainly with the forms of small-scale outbreaks or sporadic events likely by contracting imported strains which prevailed in Southeast Asia. Sustained local transmission of certain strain was also evident by WGS analysis, but not by conventional pulsotyping, highlighting the importance of continuing molecular surveillance of typhoid fever with adequate tools in the non-endemic region.


Assuntos
Dinâmica Populacional , Febre Tifoide/epidemiologia , Febre Tifoide/transmissão , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Demografia , Surtos de Doenças , Genoma Humano , Humanos , Filogenia , Salmonella typhi/isolamento & purificação , Taiwan/epidemiologia , Febre Tifoide/tratamento farmacológico , Febre Tifoide/microbiologia , Sequenciamento Completo do Genoma
14.
Fish Shellfish Immunol ; 94: 58-65, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31470137

RESUMO

TIR domain-containing protein is an important member for some bacterial pathogens to subvert host defenses. Here we described a fish virulent Yersinia ruckeri SC09 strain that interfered directly with Toll-like receptor (TLR) function by a TIR-containing protein. Firstly, the novel TIR-containing protein was identified by bioinformatics analysis and named as TcpA. Secondly, the toxic effects of TcpA in fish was demonstrated in vivo challenge experiments through knockout mutant and complement mutant of tcpA gene. Thirdly, The study in vitro revealed that TcpA could down-regulate the expression and secretion of IL-6, IL-1ß and TNF-α. Finally, we demonstrated that TcpA could inhibit the TLR signaling pathway through interaction with myeloid differentiation factor 88 (MyD88) in experiments such as NF-κB dependent luciferase reporter system, co-immunoprecipitation, GST pull-down and yeast two-hybrid. The study revealed that TcpA was essential for virulence and was able to interact with the TIR adaptor protein MyD88 and inhibit the pre-inflammatory signal of immune cells and promote the intracellular survival of pathogenic Yersinia ruckeri SC09 strain. In conclusion, our results showed that TcpA acted as a new virulence factor in Y. ruckeri could suppress innate immune response and increase virulence by inhibiting TLR and MyD88-mediated specific signaling, highlighting a novel strategy for innate immune evasion in bacteria.

15.
Artigo em Inglês | MEDLINE | ID: mdl-31272359

RESUMO

Ahead of Print article withdrawn by publisher.

16.
Fish Shellfish Immunol ; 92: 377-383, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31202969

RESUMO

Vibrio mimicus (V. mimicus) is a significant pathogen in freshwater catfish, though knowledge of virulence determinants and effective vaccine is lacking. Multiplex genome editing by natural transformation (MuGENT) is an easy knockout method, which has successfully used in various bacteria except for V. mimicus. Here, we found V. mimicus strain SCCF01 can uptake exogenous DNA and insert it into genome by natural transformation assay. Subsequently, we exploited this property to make five mutants (△Hem, △TS1, △TS2, △TS1△TS2, and △II), and removed the antibiotic resistance marker by Flp-recombination. Finally, all of the mutants were identified by PCR and RT-PCR. The results showed that combination of natural transformation and FLP-recombination can be applied successfully to generate targeted gene disruptions without the antibiotic resistance marker in V. mimicus. In addition, the five mutants showed mutant could be inherited after several subcultures and a 668-fold decrease in the virulence to yellow catfish (Pelteobagrus fulvidraco). This study provides a convenient method for the genetic manipulation of V. mimicus. It will facilitate the identification and characterization of V. mimicus virulence factors and eventually contribute to a better understanding of V. mimicus pathogenicity and development of attenuated vaccine.


Assuntos
Vacinas Bacterianas/imunologia , Peixes-Gato , Doenças dos Peixes/imunologia , Edição de Genes/veterinária , Técnicas de Inativação de Genes/veterinária , Vibrio mimicus/imunologia , Animais , Técnicas de Inativação de Genes/métodos , Vacinas Atenuadas/imunologia , Vibrioses/imunologia , Vibrioses/veterinária
17.
J Transl Med ; 17(1): 204, 2019 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-31215436

RESUMO

BACKGROUND: Neutrophil gelatinase-associated lipocalin (NGAL) is a promising biomarker of early diagnosis and prediction for acute kidney injury (AKI). However, the current program for NGAL detection is not extensively applied in clinics due to the high expense of antibodies. Nucleic acid aptamers are single-strand DNAs or RNAs which could bind to targets with high specificity and affinity, and they have been widely used in the diagnosis and therapy for multiple diseases. It is valuable for us to develop a new method for NGAL detection using aptamers instead of antibodies to achieve increased efficiency and decreased cost. METHODS: Nucleic acid aptamers against NGAL were obtained after SELEX process using magnetic beads, and an enzyme-linked aptamer analysis (ELAA), which can be widely used in clinical diagnosis at low cost, were successfully established. The feasibility of ELAA was further validated with urine samples harvested from 43 AKI patients and 30 healthy people. RESULTS: Three candidate aptamers, including NA36, NA42 and NA53, were obtained after 8 rounds of SELEX process with magnetic beads and verified by quantitative polymerase chain reaction (qPCR), and the Kd value of each aptamer was 43.59, 66.55 and 32.52 nM, respectively. Moreover, the linear relationship was consistent at the range of 125-4000 ng/mL, and the detection limit of ELAA assay was 30.45 ng/mL. We also found that NGAL could be exclusively detected with NA53, and no cross-reaction between NA53 and human albumin or globulin occurred, the coefficient of variation (CV) between inner-plate and inter-plate was less than 15%, and the recovery rate was between 80 and 110%. Moreover, the sensitivity and specificity of ELAA assay in this study are 100% and 90%, respectively. Consistently, these results could also diagnose whether the occurrence of AKI in lots of patients, which has been demonstrated with the ELAA method we established after using NA53. CONCLUSIONS: Taken together, NA53, the best candidate aptamer targeting NGAL protein, can be applied in clinical testing.

18.
Magn Reson Imaging ; 61: 9-15, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31071471

RESUMO

PURPOSE: To explore the possibility of using amide proton transfer-weighted imaging (APTWI) for the identification and diagnosis of cervical squamous carcinoma (CSC), cervical adenocarcinoma (CA) and different levels of CSC. MATERIALS AND METHODS: Seventy-six patients with newly diagnosed uterine cervical cancer (UCC) were studied prior to treatment, including 20 with poorly differentiated (Grade 3) CSC, 23 with moderately differentiated (Grade 2) CSC, 17 with well-differentiated (Grade 1) CSC, and 16 with CA (13 with poorly differentiated (Grade 3) CA and 3 with moderately differentiated (Grade 2) CA). Differences in the magnetization transfer ratio at 3.5 ppm (MTRasym (3.5 ppm)) were identified between CSC and CA and between high-level (Grade 3) CSC and low-level (Grade 2 and Grade 1) CSC, as well as among all three grades of CSC differentiation. Receiver operating characteristic (ROC) curve analysis was used to evaluate the diagnostic thresholds and performance of the parameters. Spearman correlation analysis was used to examine the correlation between the MTRasym (3.5 ppm) and histological grade. RESULTS: The MTRasym (3.5 ppm) in CA was higher than that in CSC (P = 0.001). The MTRasym (3.5 ppm) in high-level CSC was higher than that in low-level CSC (P = 0.001). The MTRasym (3.5 ppm) was positively correlated with the grade of CSC differentiation (r = 0.498, P = 0.001). The MTRasym (3.5 ppm) in Grade 3 CSC was higher than that in Grade 2 and Grade 1 CSC (P = 0.02/0.01). No significant difference in the MTRasym (3.5 ppm) was found between Grade 2 CSC and Grade 1 CSC (P = 0.173). The area under the ROC curve (AUC) for the MTRasym (3.5 ppm) in distinguishing CSC and CA was 0.779, with a cut-off, sensitivity, and specificity of 2.97%, 60.0% and 82.5%, respectively. The AUC for distinguishing high-/low-level CSC was 0.756, with a cut-off, sensitivity, and specificity of 3.29%, 68.8% and 83.3%, respectively. CONCLUSION: APTWI may be a useful technique for the identification and diagnosis of CSC, CA and different levels of CSC, which may have an important impact on clinical strategies for treating patients with UCC.


Assuntos
Adenocarcinoma/diagnóstico por imagem , Adenocarcinoma/patologia , Carcinoma de Células Escamosas/diagnóstico por imagem , Carcinoma de Células Escamosas/patologia , Imagem por Ressonância Magnética/métodos , Neoplasias do Colo do Útero/diagnóstico por imagem , Neoplasias do Colo do Útero/patologia , Idoso , Amidas , Colo do Útero/diagnóstico por imagem , Colo do Útero/patologia , Diagnóstico Diferencial , Feminino , Humanos , Pessoa de Meia-Idade , Gradação de Tumores , Prótons , Curva ROC , Sensibilidade e Especificidade
19.
Cell Biosci ; 9: 31, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30962873

RESUMO

Pyroptosis, a type of programmed cell death that along with inflammation, is mainly regulated by two main pathways, cysteinyl aspartate specific proteinase (caspase)-1-induced canonical inflammatory pathway and caspase-11-induced non-canonical inflammatory pathway. The non-canonical inflammatory pathway-induced pyroptosis is a unique immune response in response to gram-negative (G-) bacteria. It is induced by lipopolysaccharide (LPS) on the surface of G- bacteria. This activates caspase-11 which, in turn, activates a series of downstream proteins eventually forming protein pores on the cell membrane and inducing cell sacrificial processes. Caspase-11 belongs to the caspase family and is an homologous protein of caspase-1. It has the ability to specifically hydrolyze proteins, but it is still unclear how it regulates cell death caused by non-canonical inflammatory pathways. The present study describes a pathway that enables LPS to directly enter the cell and activate caspase-11, and the key role caspase-11 plays in the activation of pyroptosis and inflammation.

20.
Pharmacogenomics ; 20(4): 273-277, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30883264

RESUMO

AIM: Exenatide is a glucagon-like peptide 1receptor agonist, having both glycemic and weight loss benefits. Given that previous pharmacogenetic studies reported inconsistent evidence of association between variants in the drug target gene GLP1R and response to exenatide, we set out to examine two common coding variants Chinese population. Materials & methods: Here, we recruited 285 overweight Type 2 diabetes patients from China and investigated the association between two common missense variants and response to exenatide, using multivariate linear model with adjustment for baseline and other covariates. Results: The variant allele T of rs10305420 was associated with a 1.27 kg (p = 0.02) less weight loss and a 0.4% (p = 0.002) lower HbA1c reduction after 6 month of exenatide treatment. CONCLUSION: The consistent large clinical impact of rs10305420 on glycemic response and weight response to exenatide makes the variant a strong candidate biomarker for precision medicine, particularly among overweight patients with Type 2 diabetes.

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