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1.
Anal Chem ; 96(24): 9961-9968, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38838250

RESUMO

In this study, a novel europium dual-ligand metal-organic gel (Eu-D-MOGs) with high-efficient anodic annihilation electrochemiluminescence (ECL) was synthesized as an ECL emitter to construct a biosensor for ultrasensitive detection of microRNA-221 (miR-221). Impressively, compared to the ECL signal of europium single-ligand metal-organic gels (Eu-S-MOGs), the ECL signal of Eu-D-MOGs was significantly improved since the two organic ligands could jointly replace the H2O and coordinate with Eu3+, which could remarkably reduce the nonradiative vibrational energy transfer caused by the coordination between H2O and Eu3+ with a high coordination demand. In addition, Eu-D-MOGs could be electrochemically oxidized to Eu-D-MOGs•+ at 1.45 V and reduced to Eu-D-MOGs•- at 0.65 V to achieve effective annihilation of ECL, which overcame the side reaction brought by the remaining emitters at negative potential. This benefited from the annihilation ECL performance of the central ion Eu3+ caused by its redox in the electrochemical process. Furthermore, the annihilation ECL signal of Eu3+ could be improved by sensitizing Eu3+ via the antenna effect. In addition, combined with the improved rolling circle amplification-assisted strand displacement amplification strategy (RCA-SDA), a sensitive biosensor was constructed for the sensitive detection of miR-221 with a low detection limit of 5.12 aM and could be successfully applied for the detection of miR-221 in the lysate of cancer cells. This strategy offered a unique approach to synthesizing metal-organic gels as ECL emitters without a coreactant for the construction of ECL biosensing platforms in biomarker detection and disease diagnosis.


Assuntos
Técnicas Eletroquímicas , Eletrodos , Európio , Géis , Medições Luminescentes , MicroRNAs , Európio/química , MicroRNAs/análise , Técnicas Eletroquímicas/métodos , Ligantes , Géis/química , Técnicas Biossensoriais/métodos , Limite de Detecção , Humanos
2.
Eur Radiol ; 33(6): 4082-4093, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36576546

RESUMO

OBJECTIVES: To investigate microvascular alterations in the Glisson system of biliary atresia (BA) patients after Kasai portoenterostomy (KP) using three-dimensional (3D) virtual histopathology based on X-ray phase-contrast CT (PCCT). METHODS: Liver explants from BA patients were imaged using PCCT, and 32 subjects were included and divided into two groups: KP (n = 16) and non-KP (n = 16). Combined with histological analysis and 3D visualization technology, 3D virtual histopathological assessment of the biliary, arterial, and portal venous systems was performed. According to loop volume ratio, 3D spatial density, relative surface area, tortuosity, and other parameters, pathological changes of microvasculature in the Glisson system were investigated. RESULTS: In the non-KP group, bile ducts mostly manifested as radial multifurcated hyperplasia and twisted into loops. In the KP group, the bile duct hyperplasia was less, and the loop volume ratio of bile ducts decreased by 13.89%. Simultaneously, the arterial and portal venous systems presented adaptive alterations in response to degrees of bile duct hyperplasia. Compared with the non-KP group, the 3D spatial density of arteries in the KP group decreased by 3.53%, and the relative surface area decreased from 0.088 ± 0.035 to 0.039 ± 0.015 (p < .01). Deformed portal branches gradually recovered after KP, with a 2.93% increase in 3D spatial density and a decrease in tortuosity from 1.17 ± 0.06 to 1.14 ± 0.04 (p < .01) compared to the non-KP group. CONCLUSION: 3D virtual histopathology via PCCT clearly reveals the microvascular structures in the Glisson system of BA patients and provides key insights into the morphological mechanism of microvascular adaptation induced by biliary tract dredging after KP in BA disease. KEY POINTS: • 3D virtual histopathology via X-ray phase-contrast computed tomography clearly presented the morphological structures and pathological changes of microvasculature in the Glisson system of biliary atresia patients. • The morphological alterations of microvasculature in the Glisson system followed the competitive occupancy mechanism in the process of biliary atresia.


Assuntos
Atresia Biliar , Humanos , Lactente , Atresia Biliar/diagnóstico por imagem , Atresia Biliar/cirurgia , Portoenterostomia Hepática/métodos , Hiperplasia , Raios X , Tomografia Computadorizada por Raios X
3.
Hepatobiliary Pancreat Dis Int ; 22(6): 584-593, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37308361

RESUMO

BACKGROUND: Early identification of patients with high mortality risk is critical for optimizing the clinical management of drug-induced liver injury (DILI). We aimed to develop and validate a new prognostic model to predict death within 6 months in DILI patients. METHODS: This multicenter study retrospectively reviewed the medical records of DILI patients admitted to three hospitals. A DILI mortality predictive score was developed using multivariate logistic regression and was validated with area under the receiver operating characteristic curve (AUC). A high-mortality-risk subgroup was identified according to the score. RESULTS: Three independent DILI cohorts, including one derivation cohort (n = 741) and two validation cohorts (n = 650, n = 617) were recruited. The DILI mortality predictive (DMP) score was calculated using parameters at disease onset as follows: 1.913 × international normalized ratio + 0.060 × total bilirubin (mg/dL) + 0.439 × aspartate aminotransferase/alanine aminotransferase - 1.579 × albumin (g/dL) - 0.006 × platelet count (109/L) + 9.662. The predictive performance for 6-month mortality of DMP score was desirable, with an AUC of 0.941 (95% CI: 0.922-0.957), 0.931 (0.908-0.949) and 0.960 (0.942-0.974) in the derivation, validation cohorts 1 and 2, respectively. DILI patients with a DMP score ≥ 8.5 were stratified into high-risk group, whose mortality rates were 23-, 36-, and 45-fold higher than those of other patients in the three cohorts. CONCLUSIONS: The novel model based on common laboratory findings can accurately predict mortality within 6 months in DILI patients, which should serve as an effective guidance for management of DILI in clinical practice.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas , Humanos , Estudos Retrospectivos , Doença Hepática Induzida por Substâncias e Drogas/diagnóstico , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Alanina Transaminase , Prognóstico
4.
Acta Pharmacol Sin ; 43(5): 1200-1209, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35165400

RESUMO

Nonalcoholic steatohepatitis (NASH) is increasingly recognized as a serious disease that can lead to cirrhosis, hepatocellular carcinoma (HCC), and death. However, there is no effective drug to thwart the progression of the disease. Development of new drugs for NASH is an urgent clinical need. Liver biopsy plays a key role in the development of new NASH drugs. Histological findings based on liver biopsy are currently used as the main inclusion criteria and the primary therapeutic endpoint in NASH clinical trials. However, there are inherent challenges in the use of liver biopsy in clinical trials, such as evaluation reliability, sampling error, and invasive nature of the procedure. In this article, we review the advantages and value of liver histopathology based on liver biopsy in clinical trials of new NASH drugs. We also discuss the challenges and limitations of liver biopsy and identify future drug development directions.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Hepatopatia Gordurosa não Alcoólica , Biópsia , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/patologia , Desenvolvimento de Medicamentos , Humanos , Fígado/patologia , Cirrose Hepática/patologia , Neoplasias Hepáticas/patologia , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/patologia , Reprodutibilidade dos Testes
5.
Radiology ; 299(3): 597-610, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33876972

RESUMO

Background Biliary obstruction leads to an increase in biliary pressure within the biliary system, which induces the morphologic adaptation of the biliary tree. Purpose To observe and to quantify the morphologic characteristics of the adaptation in a bile duct ligation rat model and verify it in patients with biliary atresia in a three-dimensional (3D) manner using x-ray phase-contrast CT. Materials and Methods A bile duct ligation model was induced in 40 male Sprague-Dawley rats, which were divided into five groups: the control group (no ligation) and groups 2, 4, 6, and 8 weeks after bile duct ligation (eight animals in each group). Liver tissue samples (approximately 1.8 cm in length and 1.3 cm in height) were imaged by using phase-contrast CT and compared with histologic analysis. With a combination of phase-contrast CT and 3D visualization technology, the entire biliary system and the intrahepatic vascular system were quantitatively analyzed according to downstream, midstream, and upstream domains based on bile duct volume, surface area, and other parameters. Additionally, liver explant tissues from 28 patients with biliary atresia were studied to determine the impact of biliary tract reconstruction. Results To offset the increased biliary pressure within the biliary system, the ductular reaction in the downstream, midstream, and upstream domains manifested as dilatation, spiderweb-like looping, and interconnected honeycomb-like patterns, respectively. The most severe ductular reaction occurred in the upstream domain, and the relative surface area (mean, 0.02 µm-1 ± 0.01, 0.04 µm-1 ± 0.01, 0.07 µm-1 ± 0.02, and 0.10 µm-1 ± 0.02 for the 2-8-week groups, respectively; P < .01 among the groups) and volume fraction of ductules (mean, 16.54% ± 4.62, 19.69% ± 6.41, 26.92% ± 5.82, and 38.34% ± 10.36 for the 2-8-week groups, respectively; P < .01 among the groups except between the 2- and 4-week groups [P = .062]) significantly increased over time. In patients with biliary atresia, it was observed that both fibrosis and proliferative ductules regressed after successful biliary tract reconstruction following Kasai portoenterostomy. Furthermore, ductular reaction was accompanied by a progressive increase in the arterial supply but a loss of portal blood supply. Conclusion X-ray phase-contrast CT with three-dimensional rendering of the biliary system in a bile duct ligation rat model provides key insights into ductular reaction or biliary self-adaptation triggered by increased biliary pressure. © RSNA, 2021 Online supplemental material is available for this article. See also the editorial by Vannier and Wang in this issue.


Assuntos
Colestase/diagnóstico por imagem , Colestase/patologia , Imageamento Tridimensional/métodos , Fígado/diagnóstico por imagem , Fígado/patologia , Tomografia Computadorizada por Raios X/métodos , Animais , Sistema Biliar/diagnóstico por imagem , Modelos Animais de Doenças , Ligadura , Fígado/irrigação sanguínea , Masculino , Ratos , Ratos Sprague-Dawley
6.
Mod Pathol ; 32(12): 1795-1805, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31300804

RESUMO

Histologically, drug-induced liver injury could be classified into acute hepatitis, chronic hepatitis, acute cholestasis, chronic cholestasis, and cholestatic hepatitis. The correlation between these histologic patterns and long-term clinical outcomes has not been well established. Therefore, we conducted a retrospective cohort study to investigate the association of histologic patterns and long-term clinical outcomes defined as biochemical normalization, persistent abnormal liver biochemistry or death at designated time points. In this study, biochemical classification was determined by R-values; histologic injury pattern was determined by morphological features. Predictive ability of clinical outcomes by these two classifications was assessed using Receiver Operating Characteristic Curves. Logistic regression was performed to identify histologic factors associated with outcomes. Totally, 88 patients with drug-induced liver injury were included for final analysis. Biochemical and histologic classification were consistent in 50 (57%) cases. 53 (60%) cases showed biochemical normalization within 6 months, and a further 11 (13%), 16 (18%), and 6 (7%) cases within 1, 2, and 3 years, respectively. Compared with biochemical classification, histologic injury pattern had better predictive ability for abnormal biochemistry at 6 months (Areas under Receiver Operating Characteristic Curves 0.92 versus 0.60, P < 0.001) and 1 year (Areas under Receiver Operating Characteristic Curves 0.94 versus 0.69, P < 0.001). Interlobular bile duct loss in >25% portal areas was independently associated with abnormal biochemistry at 6 months, 1 year, and 2 years. In conclusion, histologic injury pattern is better correlated with clinical outcome at 6 months and 1 year than biochemical classification. Moderate bile duct loss is an important histologic feature associated with persistent biochemical abnormality at 6 months, 1 year, and 2 years.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas/classificação , Doença Hepática Induzida por Substâncias e Drogas/patologia , Adolescente , Adulto , Idoso , Criança , Estudos de Coortes , Feminino , Humanos , Testes de Função Hepática , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto Jovem
7.
Zhonghua Gan Zang Bing Za Zhi ; 21(4): 295-8, 2013 Apr.
Artigo em Zh | MEDLINE | ID: mdl-24021793

RESUMO

OBJECTIVE: To generate a comprehensive clinical profile of intrahepatic cholestasis of pregnancy (ICP) by systematically reviewing ICP cases managed in our hospital. METHODS: The recorded clinical data, including diagnosis, complications, management, and maternal and infant outcomes, of nine ICP cases were collected retrospectively and reviewed systematically. RESULTS: Seven of the nine total ICP patients presented with pruritus. All nine of the ICP patients showed bile acid level beyond the normal range. ICP complications included gestational hypertension (n = 3), diabetes mellitus (DM, n = 1) and impaired glucose tolerance (IGT, n = 1), and pre-eclampsia (n = 1). The infant of one patient with severe ICP showed meconium-stained liquor. All nine of the ICP patients underwent surgical delivery, of which three were delivered preterm (between the 35th and 36th week of gestation). All mothers' total bile acids declined to normal levels after delivery, and all infants survived without complication. CONCLUSION: ICP does not increase the puerpera mortality rate and does not represent a poor prognosis for infants. Bile acid levels in the ICP patients, however, may be related to the extent of premature delivery time. While the standard drug treatment of ursodeoxycholic acid is suitable for most ICP cases, those with insufficient gestational age may benefit from adjuvant corticosteroid therapy to promote fetal lung maturation prior to preterm delivery. Severe ICP cases should be managed by inducing artificial labor or performing Caesarean section.


Assuntos
Resultado da Gravidez , Ácido Ursodesoxicólico , Ácidos e Sais Biliares , Feminino , Humanos , Gravidez , Prurido , Estudos Retrospectivos , Ácido Ursodesoxicólico/uso terapêutico
8.
J Dig Dis ; 24(5): 332-339, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37460777

RESUMO

OBJECTIVES: Drug-induced liver injury (DILI) is an increasing etiology of liver dysfunction, with various incidence worldwide. To better understand the disease burden and establish appropriate preventive and treatment strategies, a systematic review and meta-analysis was conducted. METHODS: PubMed, EMBASE, Web of Science, and Cochrane Library were searched for studies on the incidence of DILI published up to June 1, 2022. According to the predefined criteria, only population-based studies were included. Incidence was presented as cases per 100 000 person-years with 95% confidence interval (CI) using a random-effects model. RESULTS: A total of 14 studies were included. The overall incidence of DILI was 4.94 per 100 000 person-years (95% CI 4.05-5.83). Time-based cumulative meta-analysis suggested that the incidence of DILI increased over time since 2010. The incidence varied by regions, with Asia having the highest incidence of 17.82 per 100 000 person-years (95% CI 6.26-29.38), while North America having the lowest incidence of 1.72 per 100 000 person-years (95% CI 0.48-2.95). All studies reported a higher incidence of DILI in the elderly but comparable incidences between male and female (3.42 per 100 000 person-years vs 4.64 per 100 000 person-years). CONCLUSIONS: The global incidence of DILI has been increasing since 2010, with the highest incidence in Asia. Understanding the epidemiological characteristics of DILI helps establish specific strategies to deal with this emerging health problems.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas , Humanos , Masculino , Feminino , Idoso , Incidência , Doença Hepática Induzida por Substâncias e Drogas/epidemiologia , Doença Hepática Induzida por Substâncias e Drogas/etiologia
9.
Cell Mol Gastroenterol Hepatol ; 15(4): 841-867, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36521660

RESUMO

BACKGROUND & AIMS: Fibroblast activation protein (FAP) is expressed on activated fibroblast. Its role in fibrosis and desmoplasia is controversial, and data on pharmacological FAP inhibition are lacking. We aimed to better define the role of FAP in liver fibrosis in vivo and in vitro. METHODS: FAP expression was analyzed in mice and patients with fibrotic liver diseases of various etiologies. Fibrotic mice received a specific FAP inhibitor (FAPi) at 2 doses orally for 2 weeks during parenchymal fibrosis progression (6 weeks of carbon tetrachloride) and regression (2 weeks off carbon tetrachloride), and with biliary fibrosis (Mdr2-/-). Recombinant FAP was added to (co-)cultures of hepatic stellate cells (HSC), fibroblasts, and macrophages. Fibrosis- and inflammation-related parameters were determined biochemically, by quantitative immunohistochemistry, polymerase chain reaction, and transcriptomics. RESULTS: FAP+ fibroblasts/HSCs were α-smooth muscle actin (α-SMA)-negative and located at interfaces of fibrotic septa next to macrophages in murine and human livers. In parenchymal fibrosis, FAPi reduced collagen area, liver collagen content, α-SMA+ myofibroblasts, M2-type macrophages, serum alanine transaminase and aspartate aminotransferase, key fibrogenesis-related transcripts, and increased hepatocyte proliferation 10-fold. During regression, FAP was suppressed, and FAPi was ineffective. FAPi less potently inhibited biliary fibrosis. In vitro, FAP small interfering RNA reduced HSC α-SMA expression and collagen production, and FAPi suppressed their activation and proliferation. Compared with untreated macrophages, FAPi regulated macrophage profibrogenic activation and transcriptome, and their conditioned medium attenuated HSC activation, which was increased with addition of recombinant FAP. CONCLUSIONS: Pharmacological FAP inhibition attenuates inflammation-predominant liver fibrosis. FAP is expressed on subsets of activated fibroblasts/HSC and promotes both macrophage and HSC profibrogenic activity in liver fibrosis.


Assuntos
Hepatite , Hepatopatias , Humanos , Camundongos , Animais , Tetracloreto de Carbono/toxicidade , Cirrose Hepática/metabolismo , Inflamação , Fibrose , Colágeno/metabolismo , Fibroblastos/metabolismo , Macrófagos/metabolismo
10.
Int J Surg ; 109(11): 3450-3458, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37578449

RESUMO

BACKGROUND: Liver allograft fibrosis (LAF) is prevalent among children with long-term survival after liver transplantation (LT). The authors aimed to identify clinical risk factors, with a focus on the impact of immunosuppression (IS) level in the early post-transplant period on LAF. METHODS: A retrospective study was conducted on pediatric LT recipients with at least 1-year of follow-up. Cox regression models were used to analyze risk factors associated with LAF, and landmark analysis was used to evaluate the impact of IS level on LAF. Longitudinal analysis was also conducted in patients with paired biopsies. RESULTS: A total of 139 patients involving 174 liver biopsies were included. With 2.3 to 5.9 years of follow-up, LAF was detected in 91.4% of patients (7.9% were significant), up to 88.2% of whom showed normal liver function. Episodes of acute rejection, biliary complications, cytomegalovirus infection, and prolonged cold ischemia time were independent risk factors. Besides, the risk of LAF in patients with relatively low IS levels at postoperative 1-3, 3-6, 6-12, and 12-36 months was higher than the counterparts. Especially, in patients with relatively high IS levels (mean tacrolimus trough concentration ≥5.1 ng/ml) during postoperative 12-36 months, the risk of LAF was 67% lower in the short future ( P =0.006). In paired analysis, patients with increased IS levels were more likely to achieve fibrosis-reduction (HR=7.53, P =0.025). CONCLUSIONS: Mild to moderate LAF is common among pediatric LT recipients and can appear early and silently. Maintaining adequate levels of IS during 1-3 years after LT seems crucial to ensure protection against LAF.


Assuntos
Transplante de Fígado , Criança , Humanos , Transplante de Fígado/efeitos adversos , Estudos Retrospectivos , Cirrose Hepática/etiologia , Cirrose Hepática/cirurgia , Terapia de Imunossupressão/efeitos adversos , Fibrose , Rejeição de Enxerto/etiologia , Rejeição de Enxerto/prevenção & controle , Aloenxertos , Imunossupressores/efeitos adversos
11.
J Dig Dis ; 24(1): 28-38, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36908183

RESUMO

OBJECTIVES: In this study we aimed to assess the clinicopathological characteristics and long-term prognosis of patients with nonalcoholic fatty liver disease (NAFLD) having distinct steatosis distribution patterns. METHODS: Clinicopathological data of 238 individuals with biopsy-confirmed NAFLD were collected. Nonalcoholic steatohepatitis-clinical research network (NASH-CRN) and steatosis, activity and fibrosis (SAF)/fatty liver inhibition of progression (FLIP) algorithm were used. Cumulative incidence of liver-related events (LREs) was compared by Kaplan-Meier analysis. Univariate and multivariate logistic regression analyses were used to identify independent predictors for steatosis distribution. RESULTS: Eligible patients were categorized into three groups based on their steatosis distribution, including azonal steatosis (AS) (62 [26.1%]), perivenular steatosis (PVS) (147 [61.8%]), and the pan-acinar steatosis (PAS) groups (29 [12.1%]). There were significantly higher ballooning grade and disease activity (P < 0.05), more severe fibrosis (P < 0.001), and a higher cumulative incidence of LREs (hazard ratio [HR] 8.0, 95% confidence interval [CI] 2.34-27.35, P < 0.0001) in the AS group than in the PVS and PAS groups after a median of 3.6-year follow-up. Multivariate logistic regression analysis revealed age (odds ratio [OR] 1.11, 95% CI 1.06-1.16, P < 0.001) might be independently associated with AS distribution, and PNPLA3 rs738409 CG/GG genotype (OR 3.36, 95% CI 0.98-11.47, P = 0.053) might also play a role. CONCLUSIONS: AS is associated with more severe disease activity and fibrosis stage in NAFLD, and predisposes toward poor prognosis. Age might be an independent predictor for AS in NAFLD, while PNPLA3 rs738409 CG/GG genotype might also play a role.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Humanos , Hepatopatia Gordurosa não Alcoólica/complicações , Genótipo , Fibrose , Gravidade do Paciente
12.
Zhonghua Nei Ke Za Zhi ; 51(8): 618-22, 2012 Aug.
Artigo em Zh | MEDLINE | ID: mdl-23158860

RESUMO

OBJECTIVE: To verify and assess diagnostic value of noninvasive diagnostic model of liver fibrosis in primary biliary cirrhosis (PBC) based on conventional laboratory markers. METHODS: Seventy-three patients with PBC diagnosed by liver biopsy between January 2003 and June 2011 in Beijing Friendship Hospital, Capital Medical University were recruited in this study. Correlation analysis and logistic regression analysis between the conventional laboratory markers and histology stages were assessed. A liver fibrosis diagnostic model was established based upon aforementioned biomarkers and verified by its sensitivity and specificity for predicting the liver fibrosis. RESULTS: The predictive model (H index) consisting of five conventional laboratory markers, i.e., platelet count, serum cholinesterase, albumin, HDL-C and prothrombin time activity, could predict advanced fibrosis (stages III-IV) with an AUC(ROC) of 0.861. The sensitivity of predicting the absence of advanced fibrosis using H index < -2.20 was 96.6% and the specificity of predicting the presence of advanced fibrosis using H index > 0.41 was 93.2%. CONCLUSION: The established noninvasive diagnostic model consisting of five laboratory markers could accurately distinguish pathological changes of early stage PBC (stages I-II) from advanced stage PBC (stages III-IV).


Assuntos
Cirrose Hepática Biliar/diagnóstico , Cirrose Hepática/diagnóstico , Biomarcadores/sangue , Feminino , Humanos , Cirrose Hepática/sangue , Cirrose Hepática/patologia , Cirrose Hepática Biliar/sangue , Cirrose Hepática Biliar/patologia , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Contagem de Plaquetas
14.
Nat Plants ; 8(3): 257-268, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35318444

RESUMO

Multicellular organisms undergo several developmental transitions during their life cycles. In contrast to animals, the plant germline is derived from adult somatic cells. As such, the juvenility of a plant must be reset in each generation. Previous studies have demonstrated that the decline in the levels of miR156/7 with age drives plant maturation. Here we show that the resetting of plant juvenility during each generation is mediated by de novo activation of MIR156/7 in Arabidopsis. Blocking this process leads to a shortened juvenile phase and premature flowering in the offspring. In particular, an Arabidopsis plant devoid of miR156/7 flowers even without formation of rosette leaves in long days. Mechanistically, we find that different MIR156/7 genes are reset at different developmental stages through distinct reprogramming routes. Among these genes, MIR156A, B and C are activated de novo during sexual reproduction and embryogenesis, while MIR157A and C are reset upon seed germination. This redundancy generates a robust reset mechanism that ensures accurate restoration of the juvenile phase in each plant generation.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , MicroRNAs , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Flores/genética , Regulação da Expressão Gênica de Plantas , MicroRNAs/genética
15.
Opt Express ; 19(4): 3599-603, 2011 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-21369183

RESUMO

An optically-controlled terahertz (THz) modulator based on nonlinear photonic crystals (PCs) is proposed, which has the merits of high speed, compactness and easy integration. The PC structure consists of point and line defects. High speed modulation of THz wave can be realized by filling one of the point defects with organic polymer polyaniline which has rapid nonlinear response time. Simulation results show that the modulation rate, modulation depth and insertion loss of the modulator achieve 2.5 GHz, 20.3 dB and 1.02 dB, respectively.

16.
Yi Chuan ; 33(4): 389-96, 2011 Apr.
Artigo em Zh | MEDLINE | ID: mdl-21482530

RESUMO

Peanut bacterial wilt (BW) caused by Ralstonia solanacearum is one of the most devastating diseases for peanut production in the world. It is believed that breeding and subsequent planting BW-resistant cultivars of peanut (Arachis hypogaea L.) should represent the most effective and economic means of controlling the disease. To illustrate the molecular mechanism of peanut resistant to BW, a BW-resistant cultivar, 'Yuanza 9102', and a BW-sensitive one, 'Zhonghua 12', were infected with Ralstonia solanacearum and differential expression of the genes related to BW-resistance was analyzed using complementary DNA amplified length polymorphism (cDNA-AFLP) technique. The infected 3-leaflet seedlings were followed for 48 h and root samples were taken at 0, 2, 10, 24 and 48 h after inoculation, respectively. A total of 12596 transcript-derived fragments (TDFs) were amplified with 256 primer combinations, including 709 differential expressed TDFs, which were generated from 119 primer combinations. Ninety-eight TDFs were randomly chosen for DNA sequence analysis. BLASTx analysis of the obtained sequences revealed that 40 TDFs encoded gene products associated with energy, transcription, signal transduction, defense, metabolism, cell growth, cell structure or/and protein synthesis. Analysis of the expression of four genes by qRT-PCR verified the results from cDNA-AFLP. Strikingly, one of the identified TDFs, 32-54-1, occurred for 47 times in a known BW-resistant SSH library. These results suggest that resistance to BW in peanut involves multifaceted biochemical and physiological reactions, including regulation of the genes involved in different pathways, such as defense, singal transduction, metabolism, transcription and abiotic stresses. The TDF 32-54-1 was predicted to be closely related to BW resistance in peanut.


Assuntos
Arachis/genética , Arachis/microbiologia , Perfilação da Expressão Gênica , Doenças das Plantas/genética , Ralstonia solanacearum , Análise do Polimorfismo de Comprimento de Fragmentos Amplificados , Reação em Cadeia da Polimerase Via Transcriptase Reversa
17.
Zhonghua Gan Zang Bing Za Zhi ; 19(2): 118-20, 2011 Feb.
Artigo em Zh | MEDLINE | ID: mdl-21492515

RESUMO

To observe the characteristics of primary biliary cirrhosis (PBC) with a suboptimal biochemical response to ursodeoxycholic acid. A total of 38 Chinse PBC patients (5 male patients, 33 female patients, average age 55 years old) with treatment of ursodeoxycholic acid in our hospital from January 1999 to January 2009 were erolled and studied retrospectively. 17 suboptimal biochemical responders mainly presented with liver diseases related symptoms including jaundice (41.1%), fatigue, anorexia (23.5%), edema and abdominal distension (11.7%). 21 good biochemical responders mainly presented with abnormal liver function tests without symptoms. The suboptimal biochemical responders had significantly higher baseline levels of total serum bilirubin, alkaline phosphatase, alanine aminotransferase, aspartate aminotransferase, immunoglobulin G and globulin as compared to the good biochemical responsers. There were no differences in gender, age and the dose of UDCA. PBC patients with liver diseases related symptoms, marked abnormal liver tests and characteristics of autoimmune hepatitis may have a suboptimal biochemical response to ursodeoxycholic acid treatment.

18.
Histol Histopathol ; 36(5): 577-586, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33851410

RESUMO

AIM: As a specialized intraparenchymal vascular conduit, hepatic sinusoids play a key role in liver microcirculation. This study aimed to explore the three-dimensional (3D) morphological changes of cirrhotic sinusoids by serial histological sections. METHODS: Cirrhosis was induced by tail vein injection of albumin in Wistar rats with a positive antibody. A total of 356 serial histological sections were prepared from liver tissue blocks of normal and cirrhotic rats. The optical microscope images were registered and reconstructed, and 3D reconstructions of the fine structures of fibrous tissues and sinusoids were subsequently visualized. RESULTS: The fibrosis area of the cirrhotic sample was 6-16 times that of the normal sample (P<0.001). Cirrhosis led to obvious changes in the distribution and morphology of sinusoids, which were mainly manifested as dilation, increased quantity and disordered distribution. Compared with normal liver, cirrhotic liver has a significantly increased volume ratio, number and volume of sinusoids (1.63-, 0.53-, and 1.75-fold, respectively, P<0.001). Furthermore, the samples were further divided into three zones according to the oxygen supply, and there were significant differences in the morphology of the sinusoids in the normal and cirrhotic samples (P<0.05). In particular, morphological parameters of the cirrhotic sinusoids near the portal area were obviously greater than those in the normal liver (P<0.05). CONCLUSION: 3D morphological structures of hepatic sinusoids were reconstructed, and the adaptive microstructure changes of cirrhotic sinusoids were accurately measured, which has an important implications for the study of hepatic microcirculation and pathological changes of cirrhosis.


Assuntos
Veias Hepáticas , Imageamento Tridimensional/métodos , Cirrose Hepática/patologia , Animais , Veias Hepáticas/anatomia & histologia , Veias Hepáticas/patologia , Fígado/patologia , Cirrose Hepática Experimental/induzido quimicamente , Microcirculação , Ratos , Ratos Wistar
19.
World J Clin Cases ; 9(35): 10792-10804, 2021 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-35047591

RESUMO

BACKGROUND: Cytomegalovirus (CMV) infection is common in liver transplant (LT)_ recipients, and biliary complications occur in a large number of patients. It has been reported that CMV-DNA is more detectable in bile than in blood. AIM: To investigate the effects of CMV infection on biliary complications by comparing the levels of CMV-DNA in the bile and blood of patients after LT. METHODS: We conducted a retrospective analysis of 57 patients who underwent LT, 10 of these patients had no biliary complications and 47 patients had biliary complications. We also compared the levels of CMV-DNA in patients' bile and blood, which were sampled concurrently. We used RNAscope technology to identify CMV in paraffin-embedded liver sections. RESULTS: CMV-DNA was not detected in bile samples and was detected in 2 blood samples from patients without biliary complications. In the 47 patients with biliary complications, CMV-DNA was detected in 22 bile samples and 8 blood samples, both bile and blood samples were positive for CMV-DNA in 6 patients. The identification rate of CMV-DNA in blood was 17.0%, and was 46.8% in bile. Moreover, tissue samples from 4 patients with biliary complications tested positive using RNAscope technology but were negative with hematoxylin and eosin staining. During the follow-up period, graft failure occurred in 13 patients with biliary complications, 8 of whom underwent retransplantation, and 3 died. CMV-DNA in bile was detected in 9 of 13 patients with graft failure. CONCLUSION: In patients with biliary complications, the identification rate of CMV-DNA in bile was higher than that in blood. Blood CMV-DNA negative patients with biliary complications should still be monitored for CMV-related biliary tract diseases. Potential occult CMV infection may also be a contributing etiological factor in the development of graft failure.

20.
Chemistry ; 16(24): 7125-33, 2010 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-20461834

RESUMO

A novel cationic Ir(III) complex [Ir(Bpq)(2)(CzbpyCz)]PF(6) (Bpq=2-[4-(dimesitylboryl)phenyl]quinoline, CzbpyCz = 5,5'-bis(9-hexyl-9H-carbazol-3-yl)-2,2'-bipyridine) containing both triarylboron and carbazole moieties was synthesized. The excited-state properties of [Ir(Bpq)(2)(CzbpyCz)]PF(6) were investigated through UV/Vis absorption and photoluminescence spectroscopy and molecular-orbital calculations. This complex displayed highly efficient orange-red phosphorescent emission with an emission peak of 583 nm and quantum efficiency of Phi=0.30 in dichloromethane at room temperature. The binding of fluoride ions to [Ir(Bpq)(2)(CzbpyCz)]PF(6) can quench the phosphorescent emission from the Ir(III) complex and enhance the fluorescent emission from the N--N ligand, which corresponds to a visual change in the emission from orange-red to blue. Thus, both colorimetric and ratiometric fluoride sensing can be realized. Interestingly, an unusual intense absorption band in the visible region was observed. And the detection of F(-) ions can also be carried out with visible light as the excitation wavelength. More importantly, the linear response of the probe absorbance change at lambda=351 nm versus the concentration of F(-) ions allows efficient and accurate quantification of F(-) ions in the range 0-50 microM.


Assuntos
Compostos de Boro/química , Carbazóis/química , Cátions/química , Fluoretos/química , Irídio/química , Substâncias Luminescentes/química , Compostos Organometálicos/química , Cristalografia por Raios X , Ligantes , Modelos Moleculares , Estrutura Molecular
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