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1.
World J Gastroenterol ; 28(34): 5023-5035, 2022 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-36160645

RESUMEN

BACKGROUND: Data that assess maternal and infant outcomes in hepatitis C virus (HCV)-infected mothers are limited. AIM: To investigate the frequency of complications and the associated risk factors. METHODS: We performed a cohort study to compare pregnancy and fetal outcomes of HCV-viremic mothers with those of healthy mothers. Risk factors were analyzed with logistic regression. RESULTS: Among 112 consecutive HCV antibody-positive mothers screened, we enrolled 79 viremic mothers. We randomly selected 115 healthy mothers from the birth registry as the control. Compared to healthy mothers, HCV mothers had a significantly higher frequency of anemia [2.6% (3/115) vs 19.0% (15/79), P < 0.001] during pregnancy, medical conditions that required caesarian section [27.8% (32/115) vs 48.1% (38/79), P = 0.004], and nuchal cords [9.6% (11/115) vs 34.2% (27/79), P < 0.001]. In addition, the mean neonatal weight in the HCV group was significantly lower (3278.3 ± 462.0 vs 3105.1 ± 459.4 gms; P = 0.006), and the mean head circumference was smaller (33.3 ± 0.6 vs 33.1 ± 0.7 cm; P = 0.03). In a multivariate model, HCV-infected mothers were more likely to suffer anemia [adjusted odds ratio (OR): 18.1, 95% confidence interval (CI): 4.3-76.6], require caesarian sections (adjusted OR: 2.6, 95%CI: 1.4-4.9), and have nuchal cords (adjusted OR: 5.6, 95%CI: 2.4-13.0). Their neonates were also more likely to have smaller head circumferences (adjusted OR: 2.1, 95%CI: 1.1-4.3) and lower birth weights than the average (≤ 3250 gms) with an adjusted OR of 2.2 (95%CI: 1.2-4.0). The vertical transmission rate was 1% in HCV-infected mothers. CONCLUSION: Maternal HCV infections may associate with pregnancy and obstetric complications. We demonstrated a previously unreported association between maternal HCV viremia and a smaller neonatal head circumference, suggesting fetal growth restriction.


Asunto(s)
Hepatitis C Crónica , Hepatitis C , Complicaciones Infecciosas del Embarazo , Estudios de Cohortes , Femenino , Hepacivirus/genética , Hepatitis C/complicaciones , Hepatitis C/diagnóstico , Hepatitis C/epidemiología , Hepatitis C Crónica/complicaciones , Humanos , Lactante , Recién Nacido , Transmisión Vertical de Enfermedad Infecciosa/prevención & control , Madres , Embarazo , Complicaciones Infecciosas del Embarazo/epidemiología , ARN Viral , Viremia/epidemiología
2.
Inflamm Res ; 69(8): 789-800, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32451556

RESUMEN

OBJECTIVE: Transmembrane protein 88 (TMEM88), a new protein of increasing concern existed in cell membrane, inhibits the typical Wnt/ß-catenin signaling pathway to play a regulatory role on cell proliferation by binding to Dishevelled-1. Until recently, the connection between TMEM88 and alcoholic liver disease is unknown. In this research, we explored the effect of TMEM88 on the secretion of inflammatory cytokines in ethanol (EtOH)-induced RAW264.7 cells, moreover, the function of YAP signaling pathway in EtOH-induced RAW264.7 cells were investigated. METHODS: We administered TMEM88 adenovirus (ADV-TMEM88) by tail vein injection into C57BL/6J mice in vivo. In vitro, RAW264.7 murine macrophages were stimulated with EtOH and were transfected with pEGFP-C1-TMEM88 and TMEM88 siRNA, respectively, protein expression and mRNA expression of IL-6 and IL-1ß were assessed by Western Blotting and RT-qPCR, respectively. RESULTS: Our group found that the overexpression of TMEM88 led to an up-regulation of IL-6 and IL-1ß secretion, hinting that it had the possibility of linking with the initiation, the development, and the end of inflammation. In addition to that, TMEM88 silencing reduced the secretion of IL-6 and IL-1ß in RAW264.7 cells. Moreover, we demonstrated that the YAP signaling pathway under the action of EtOH was activated by TMEM88. CONCLUSIONS: All in all, these experimental outcomes indicated that TMEM88 had an indispensable impact on EtOH-induced secretion of inflammatory cytokines (IL-6 and IL-1ß) in RAW264.7 cells through YAP signaling pathway.


Asunto(s)
Citocinas/biosíntesis , Lipoproteínas/fisiología , Hepatopatías Alcohólicas/etiología , Proteínas de la Membrana/fisiología , Transactivadores/fisiología , Animales , Apoptosis/efectos de los fármacos , Etanol/farmacología , Hepatopatías Alcohólicas/inmunología , Masculino , Ratones , Ratones Endogámicos C57BL , Células RAW 264.7 , Transducción de Señal/fisiología
3.
Pharmacol Res ; 150: 104501, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31689520

RESUMEN

Alcoholic liver disease (ALD) is a major cause of chronic liver disease worldwide that afflicts human health. With the in-depth study of the disease, its pathogenesis has gradually become clear. Although great breakthroughs have been made in the research of ALD, the research and development of drugs related to ALD has lagged behind seriously. However, natural products have always inspired the development of drugs. Meanwhile, there is evidence that some natural products can also play a certain role in the treatment of ALD. Thus, we reviewed the natural products, extracts and formulations with potential anti-ALD activities by consulting the relevant data in the databases of PubMed, Web of Science and CNKI databases, in order to elucidate the regulated mechanism of these natural products. Sum up, the insights provided in present review will be needed for further exploration of botanical drugs in the development of ALD therapy.


Asunto(s)
Productos Biológicos/uso terapéutico , Hepatopatías Alcohólicas/tratamiento farmacológico , Animales , Humanos , Hepatopatías Alcohólicas/metabolismo , Medicina Tradicional China , Aceites Volátiles/uso terapéutico , Fitoterapia , Transducción de Señal
4.
Biomed Res Int ; 2016: 1893474, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27314010

RESUMEN

In this study, the authors have developed endoscopic fibre-optic pressure sensor to detect variceal pressure and presented the validation of in vivo and in vitro studies, because the HVPG requires catheterization of hepatic veins, which is invasive and inconvenient. Compared with HVPG, it is better to measure directly the variceal pressure without puncturing the varices in a noninvasive way.


Asunto(s)
Endoscopía/instrumentación , Endoscopía/métodos , Várices Esofágicas y Gástricas/fisiopatología , Esófago/fisiopatología , Animales , Perros , Femenino , Venas Hepáticas/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Presión , Reproducibilidad de los Resultados
5.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(8): 2252-6, 2015 Aug.
Artículo en Chino | MEDLINE | ID: mdl-26672304

RESUMEN

In order to achieve precisely two-dimensional spatial distribution reconstruction of smoke plume, passive MAX-DOAS tomography is established, the measurement of the spatial distribution of the exhaust plume is implemented by more passive multi-axis differential absorption spectrum system. First, the multi-axis differential absorption spectrum system and its mechanism of inverse gas concentration are introduced in the paper. Then, algebra iterative algorithm is adopted to extract the information of the trace gas concentration in reconstruction simulation with different models and different scanning optical path, and the reconstruction program is designed. Then, the numerical simulation results are compared. Finally, a platform of multi-axis differential absorption optical tomography system is set up, a field campaign was carried out. The numerical simulation results show that the MAX-DOAS tomography can accurately reconstruct two-dimensional spatial distribution of plume model, the re- construction error of MAX-DOAS tomography with four light sources is about a third of the reconstruction error with double light sources, moreover, the reconstruction time is about a quarter of the reconstruction time of double light sources, and the reconstruction error of the twin peaks model is greater than that of the one peak model. Field test results show that the integral data of reconstruction image is consistent with the measured projection data of multi-axis differential absorption spectrum, the spatial distribution reconstruction of plume is in line with the actual situation. Studies have shown that the result of numerical simulation and field test results have consistency.

6.
Guang Pu Xue Yu Guang Pu Fen Xi ; 33(2): 444-7, 2013 Feb.
Artículo en Chino | MEDLINE | ID: mdl-23697129

RESUMEN

Nitrate radical (NO3) is the most important oxidant in the tropospheric nighttime chemistry. Due to its high reactivity and low atmospheric concentrations, modern red light emitting diodes (LEDs) was proposed as light source in long path differential optical absorption spectroscopy (LP-DOAS) to measure NO3 radical in the atmosphere. The spectral properties of Luxeon LXHL-MD1D LEDs were analyzed in the present paper. The principle of LEDs-DOAS system to measure nitrate radical was studied in this paper. The experimental setup and retrieval method of NO3 radical were discussed in this paper. The retrieved example of NO3 was given and the time series of NO3 concentrations was performed for a week. The results showed that the detection limits of LEDs-DOAS system were 12 ppt for atmospheric NO3 radical when the optical path of LEDs-DOAS system was 2.8 km.

7.
World J Gastroenterol ; 19(46): 8745-51, 2013 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-24379595

RESUMEN

AIM: To construct normal values for the tests of the psychometric hepatic encephalopathy score (PHES) and to evaluate its usefulness in the diagnosis of minimal hepatic encephalopathy (MHE) among Chinese individuals with cirrhosis. METHODS: The five tests of PHES, number connection test-A (NCT-A), number connection test-B, serial dotting test, line tracing test and digit symbol test (DST), were administered to all enrolled subjects in a quiet room with sufficient light. Cirrhotic subjects with overt HE were excluded by the West-Haven criteria and a detailed neurological examination. Based on the nomograms of healthy volunteers, the patients were classified as having MHE when their PHES was less than -4. RESULTS: In total, 146 healthy volunteers completed all the PHES tests. Age and education years were confirmed to be predictors of all five tests. In total, 53 patients with liver cirrhosis completed the PHES. Of the patients with liver cirrhosis, 24 (45.3%), 22(41.5%) and 7(13.2%) had Child-Pugh grades A, B and C, respectively. MHE was diagnosed in 26 patients (49.1%). Compared with compensated cirrhotic patients (Child A), decompensated cirrhotic patients (Child B and C) had a higher proportion of MHE (65.5% vs 29.2%). No differences in age and education years were found between the MHE and non-MHE groups. NCT-A and DST were able to diagnose MHE with a sensitivity of 76.9% and a specificity of 96.3% (AUC = 0.866, K = 0.735). CONCLUSION: The proportion of MHE is associated with liver function. NCT-A and DST are simple tools that can be used for the diagnosis of MHE in China.


Asunto(s)
Encefalopatía Hepática/diagnóstico , Pruebas Neuropsicológicas , Psicometría , Adulto , Anciano , Pueblo Asiatico/psicología , Estudios de Casos y Controles , China/epidemiología , Cognición , Femenino , Encefalopatía Hepática/etnología , Encefalopatía Hepática/psicología , Humanos , Cirrosis Hepática/complicaciones , Pruebas de Función Hepática , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Reproducibilidad de los Resultados , Índice de Severidad de la Enfermedad , Adulto Joven
8.
PLoS One ; 6(11): e27282, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-22073304

RESUMEN

Ulcerative colitis is a gastrointestinal disorder characterized by local inflammation and impaired epithelial barrier. Previous studies demonstrated that CXC chemokine receptor 4 (CXCR4) antagonists could reduce colonic inflammation and mucosal damage in dextran sulfate sodium (DSS)-induced colitis. Whether CXCR4 antagonist has action on intestinal barrier and the possible mechanism, is largely undefined. In the present study, the experimental colitis was induced by administration of 5% DSS for 7 days, and CXCR4 antagonist AMD3100 was administered intraperitoneally once daily during the study period. For in vitro study, HT-29/B6 colonic cells were treated with cytokines or AMD3100 for 24 h until assay. DSS-induced colitis was characterized by morphologic changes in mice. In AMD3100-treated mice, epithelial destruction, inflammatory infiltration, and submucosal edema were markedly reduced, and the disease activity index was also significantly decreased. Increased intestinal permeability in DSS-induced colitis was also significantly reduced by AMD3100. The expressions of colonic claudin-1, claudin-3, claudin-5, claudin-7 and claudin-8 were markedly decreased after DSS administration, whereas colonic claudin-2 expression was significantly decreased. Treatment with AMD3100 prevented all these changes. However, AMD3100 had no influence on claudin-3, claudin-5, claudin-7 and claudin-8 expression in HT-29/B6 cells. Cytokines as TNF-α, IL-6, and IFN-γ increased apoptosis and monolayer permeability, inhibited the wound-healing and the claudin-3, claudin-7 and claudin-8 expression in HT-29/B6 cells. We suggest that AMD3100 acted on colonic claudin expression and intestinal barrier function, at least partly, in a cytokine-dependent pathway.


Asunto(s)
Claudinas/metabolismo , Colitis/fisiopatología , Inhibidores de Fusión de VIH/farmacología , Compuestos Heterocíclicos/farmacología , Mucosa Intestinal/fisiopatología , Receptores CXCR4/antagonistas & inhibidores , Animales , Bencilaminas , Western Blotting , Colitis/metabolismo , Ciclamas , Femenino , Células HT29 , Humanos , Inmunohistoquímica , Ratones , Ratones Endogámicos BALB C
9.
Guang Pu Xue Yu Guang Pu Fen Xi ; 30(8): 2292-4, 2010 Aug.
Artículo en Chino | MEDLINE | ID: mdl-20939360

RESUMEN

Due to heavy air pollutants and aerosols in our country, the model for simultaneous evaluation of aerosol parameters and trace gases based on differential optical absorption spectroscopy is developed in the present paper. The spectra were used to get the concentrations of many trace gases and mean geometrical diameter, total number concentration and total volume of aerosol simultaneously over the same air volume. Retrieval of aerosol parameters was performed by the "table look-up" method based on total extinction coefficient. Experimental results show that trace gases and aerosol parameters can be successfully retrieved using this model.

10.
Guang Pu Xue Yu Guang Pu Fen Xi ; 29(8): 2126-30, 2009 Aug.
Artículo en Chino | MEDLINE | ID: mdl-19839323

RESUMEN

Ozone (O3) often serves as the benchmark for the overall pollution level of a given airshed and it is critical that the measurement technique be accurate and precise, In the DOAS measurement, the accuracy of O3 concentration is determined by the selected spectral range. The present paper focuses on the effect of spectral range on the detected characteristic absorption structure of O3, and the variation of differential cross section of O3 with the change in spectral range and the source of interference in different spectral range. The effect of practical atmospheric light extinction on the light intensities of different spectral ranges was deduced; the effect of spectral range on the accuracy was determined by detecting the standard gases at different concentration and different spectral resolution. The optimized spectral range was determined for O3, which can yield high sensitivity, good selectivity and a reasonable time resolution for the accurate qualitative and quantitative analysis of O3.

11.
Huan Jing Ke Xue ; 30(6): 1567-73, 2009 Jun 15.
Artículo en Chino | MEDLINE | ID: mdl-19662832

RESUMEN

The concentration of HONO, NO2, O3 and other atmospheric pollutants were observed continuously by using differential optical absorption spectroscopy (DOAS) from 2007-08-14 to 2007-08-24 in Beijing, China. Diurnal variation characteristics of HONO and NO2 were analyzed. The HONO levels originated from the nocturnal direct emission were discussed. And the correlation between the heterogeneous formation of HONO and its related factors (BC, RH, and so on) was studied. The results showed that HONO had two peaks at about 01:00 and 06:00, respectively, while two peaks of NO2 concentrations appeared at about 01:00 and 07:00. The highest HONO(em)/HONO ratio of 31.3% was observed at about 20:00 between 19:00 to 07:00, and the average ratio was 15%. Good correlation of HONO(corr)/NO2 ratio with BC and RH at night was obtained. The correlation suggested that heterogeneous NO2 to HONO conversion processes may occur on BC surfaces by reaction with absorption water, and the average nighttime conversion frequency from NO2 into HONO (HONO/NO2) was calculated about 0.8% x h(-1). At the same time, the results showed that heterogeneous formation of HONO was increased with RH and inhibited at RH > 80%, and the hypothesis was further supported by detailed analysis of selected case.


Asunto(s)
Contaminantes Atmosféricos/análisis , Atmósfera/análisis , Óxido Nítrico/análisis , Dióxido de Nitrógeno/análisis , Ácido Nitroso/química , China , Monitoreo del Ambiente/métodos , Oxidantes Fotoquímicos/análisis , Fotoquímica , Estaciones del Año
12.
Guang Pu Xue Yu Guang Pu Fen Xi ; 29(2): 413-7, 2009 Feb.
Artículo en Chino | MEDLINE | ID: mdl-19445217

RESUMEN

The method of retrieving the concentration of trace gases using of the diagnostic absorption of trace gases based on the scattered sunlight is called passive DOAS. It has been developed so fast in recent years because it remains simple and is prone to being combined with different platform. While retrieving the column density of trace gases with the scattered sunlight as light source, it will be affected strongly by solar Fraunhofer lines, which is also called Ring effect. It makes it hard to retrieve trace gases concentration and affects measurement precision, especially for lower concentration. The influence of Ring effect and its relation with solar zenith angle in stable day will be introduced in the present paper, and the modification will be provided so that different Ring spectrum is selected according to different solar zenith angle. The slant column density (SCD) of NO2 for 3 stable days was retrieved with this modification. It was proved that the modification is possible.

13.
Guang Pu Xue Yu Guang Pu Fen Xi ; 29(11): 3057-60, 2009 Nov.
Artículo en Chino | MEDLINE | ID: mdl-20101985

RESUMEN

For real-time and on-line monitoring DOAS (differential optical absorption spectroscopy) system, a model based on an improved Elman network for monitoring pollutant concentrations was proposed. In order to reduce the systematical complexity, the forecasting factors have been obtained based on the step-wise regression method. The forecasting factors were current concentrations, temperature and relative humidity, and wind speed and wind direction. The dynamic back propagation (BP) algorithm was used for creating training set. The experiment results show that the predicted value follows the real well. So the modified Elman network can meet the demand of DOAS system's real time forecasting.

14.
Guang Pu Xue Yu Guang Pu Fen Xi ; 28(3): 507-11, 2008 Mar.
Artículo en Chino | MEDLINE | ID: mdl-18536400

RESUMEN

Featuring excellent response characteristics and detection sensitivity and with much lower operational cost, differential optical absorption spectroscopy (DOAS) can be a powerful tool to trace concentration variation of trace indicators -O3, Ox (O3 + NO2) and HCHO for fast VOCs atmospheric photochemistry. But it's difficult to measure those gases accurately because of trace concentration. Here using a self-made DOAS system, the accurate measurement of those indicators was achieved through improving the ratio of signal to noise ratio and correcting the background scattering light; the retrieving method of those indicators was developed through eliminating the temperature effect of absorption cross section, accurately removing the intrinsic structure and lamp structure of spectrum. The preference of different spectral windows that could be used for the concentration retrieval of those indicators was analyzed and compared including interfering factors, results retrieved and the accuracy.

15.
Guang Pu Xue Yu Guang Pu Fen Xi ; 27(7): 1254-8, 2007 Jul.
Artículo en Chino | MEDLINE | ID: mdl-17944388

RESUMEN

Long path differential optical absorption spectroscopy (LP-DOAS) can be used to retrieve the concentration of trace gases based on the principle of least squares. LP-DOAS permits the sensitive measurement of concentrations of trace gases. However, the calculation of a statistically sound measurement precision still remains an unsolved problem. The absorbance of atmospheric trace gases is usually very weak, so the interference caused by the occurrence of non-reproducible spectral artifacts often determines the detection limit and the measurement precision. These spectral artifacts bias the least squares fitting result in two respects. Spectral artifacts are falsely interpreted as real absorption, and spectral artifacts add non-statistical noise to spectral residuals, resulting in a significant underestimation of the least squares fitting error. Monte Carlo method was presented to investigate the evaluation errors in DOAS spectra accurately. Residual inspection by cyclic displacement was used to estimate the effect of false interpretation of the artifact structures. The evaluation of simulated atmospheric measurement spectra shows that Monte Carlo method yields a good estimate of the spectra evaluation error. It is approximately real error, factors of errors are 1.13, but errors are ordinarily underestimated by err(LSQ), and factors of errors are 3.12.

16.
Guang Pu Xue Yu Guang Pu Fen Xi ; 26(12): 2291-3, 2006 Dec.
Artículo en Chino | MEDLINE | ID: mdl-17361733

RESUMEN

Differential optical absorption spectroscopy (DOAS) has become a widely used method to measure trace gases in the atmosphere. Concentration of trace gases is retrieved using least-squares fits of reference spectra to the measurement spectra. The measurement precision not only depends on the measurement precision of spectra and the noise of instrument and disturbing of other gases in measuring band, but suffers the influence of signal sampling and pre-processing. The present paper simply introduced DOAS measuring principle and the setup of instrument and put forward improving method-the technology of over sampling sigma- deltaA/D. Using the sigma-delta modulator structure to shape noises together with the over sampling technology can doubly restrain quantifying noises, which can improve the signal-to-noise ratio within the measuring band. So the measurement precision of DOAS system is improved with this technology.

17.
Ai Zheng ; 23(12): 1622-7, 2004 Dec.
Artículo en Chino | MEDLINE | ID: mdl-15601549

RESUMEN

BACKGROUND & OBJECTIVE: Multidrug resistant (MDR) cells can resist drug-induced apoptosis, which is the functional mechanism for many chemotherapeutic drugs. It is necessary to search for the molecular mechanism underlying anti-apoptosis of MDR cells. However, because of the anti-apoptosis characteristic of MDR cells, it is hard to study the mechanism on their apoptosis pathway. This study was to induce apoptosis in human acute leukemia cell line HL-60, and its MDR cell lines HR20 and HT9 by cyclosporin A (CsA), analyze the differences in apoptosis pathway between MDR cells and sensitive cells by detecting several important apoptosis-related molecules. METHODS: HL-60, HR20, and HT9 cells were treated with 10, and 20 mg/L of CsA, cell apoptosis was identified by cell morphologic changes,electrophoresis,and flow cytometry. Changes of apoptosis-related factors were detected by spectrophotometer and Western blot. RESULTS: HL-60, HR20, and HT9 cells all showed obvious apoptotic characteristics after treated with CsA,such as chromatin condensation, DNA fragmentation factor (DFF) degradation and activation, and DNA fragmentation. However, Caspase-3 activation was only detected in apoptotic HL-60 cells. CONCLUSIONS: CsA may induce apoptosis of HR20, and HT9 cells in a Caspase-3 independent manner, which is different from apoptosis of sensitive cells. In the apoptosis pathway of HR20, and HT9 cells, there may be some factors other than Caspase-3 that can activate DFF. It is postulated that the difficulty of Caspase-3 to be activated may be an important reason for HR20 and HT9 cells to resist apoptosis induced by many chemotherapeutic drugs.


Asunto(s)
Apoptosis/efectos de los fármacos , Caspasas/metabolismo , Ciclosporina/farmacología , Resistencia a Múltiples Medicamentos , Resistencia a Antineoplásicos , Proteínas Reguladoras de la Apoptosis , Caspasa 3 , Núcleo Celular/patología , Daunorrubicina/farmacología , Relación Dosis-Respuesta a Droga , Doxorrubicina/farmacología , Células HL-60 , Humanos , Proteínas/metabolismo , Vincristina/farmacología
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