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1.
Biochem Biophys Res Commun ; 702: 149654, 2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38340657

RESUMEN

Accumulating evidence underscores the pivotal role of envelope proteins in viral secondary envelopment. However, the intricate molecular mechanisms governing this phenomenon remain elusive. To shed light on these mechanisms, we investigated a Golgi-retained gD of EHV-1 (gDEHV-1), distinguishing it from its counterparts in Herpes Simplex Virus-1 (HSV-1) and Pseudorabies Virus (PRV). To unravel the specific sequences responsible for the Golgi retention phenotype, we employed a gene truncation and replacement strategy. The results suggested that Golgi retention signals in gDEHV-1 exhibiting a multi-domain character. The extracellular domain of gDEHV-1 was identified as an endoplasmic reticulum (ER)-resident domain, the transmembrane domain and cytoplasmic tail (TM-CT) of gDEHV-1 were integral in facilitating the protein's residence within the Golgi complex. Deletion or replacement of either of these dual domains consistently resulted in the mutant gDEHV-1 being retained in an ER-like structure. Moreover, (TM-CT)EHV-1 demonstrated a preference for binding to endomembranes, inducing the generation of a substantial number of vesicles, potentially originate from the Golgi complex or the ER-Golgi intermediate compartment. In conclusion, our findings provide insights into the intricate molecular mechanisms governing the Golgi retention of gDEHV-1, facilitating the comprehension of the processes underlying viral secondary envelopment.


Asunto(s)
Herpesvirus Équido 1 , Proteínas del Envoltorio Viral , Animales , Caballos , Proteínas del Envoltorio Viral/química , Herpesvirus Équido 1/metabolismo , Aparato de Golgi/metabolismo , Retículo Endoplásmico/metabolismo , Dominios Proteicos
2.
J Transl Med ; 22(1): 507, 2024 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-38802851

RESUMEN

BACKGROUND: Gastric cancer (GC) ranks fifth in global cancer incidence and third in mortality rate among all cancer types. Circular RNAs (circRNAs) have been extensively demonstrated to regulate multiple malignant biological behaviors in GC. Emerging evidence suggests that several circRNAs derived from FNDC3B play pivotal roles in cancer. However, the role of circFNDC3B in GC remains elusive. METHODS: We initially screened circFNDC3B with translation potential via bioinformatics algorithm prediction. Subsequently, Sanger sequencing, qRT-PCR, RNase R, RNA-FISH and nuclear-cytoplasmic fractionation assays were explored to assess the identification and localization of circ0003692, a circRNA derived from FNDC3B. qRT-PCR and ISH were performed to quantify expression of circ0003692 in human GC tissues and adjacent normal tissues. The protein-encoding ability of circ0003692 was investigated through dual-luciferase reporter assay and LC/MS. The biological behavior of circ0003692 in GC was confirmed via in vivo and in vitro experiments. Additionally, Co-IP and rescue experiments were performed to elucidate the interaction between the encoded protein and c-Myc. RESULTS: We found that circ0003692 was significantly downregulated in GC tissues. Circ0003692 had the potential to encode a novel protein FNDC3B-267aa, which was downregulated in GC cells. We verified that FNDC3B-267aa, rather than circ0003692, inhibited GC migration in vitro and in vivo. Mechanistically, FNDC3B-267aa directly interacted with c-Myc and promoted proteasomal degradation of c-Myc, resulting in the downregulation of c-Myc-Snail/Slug axis. CONCLUSIONS: Our study revealed that the novel protein FNDC3B-267aa encoded by circ0003692 suppressed GC metastasis through binding to c-Myc and enhancing proteasome-mediated degradation of c-Myc. The study offers the potential applications of circ0003692 or FNDC3B-267aa as therapeutic targets for GC.


Asunto(s)
Fibronectinas , Metástasis de la Neoplasia , Complejo de la Endopetidasa Proteasomal , Proteínas Proto-Oncogénicas c-myc , ARN Circular , Neoplasias Gástricas , Neoplasias Gástricas/patología , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo , Humanos , ARN Circular/genética , ARN Circular/metabolismo , Complejo de la Endopetidasa Proteasomal/metabolismo , Línea Celular Tumoral , Proteínas Proto-Oncogénicas c-myc/metabolismo , Proteínas Proto-Oncogénicas c-myc/genética , Animales , Fibronectinas/metabolismo , Regulación Neoplásica de la Expresión Génica , Masculino , Proteolisis , Ratones Desnudos , Secuencia de Bases , Movimiento Celular/genética , Femenino , Ratones
3.
Biochem Biophys Res Commun ; 617(Pt 2): 41-47, 2022 08 30.
Artículo en Inglés | MEDLINE | ID: mdl-35689841

RESUMEN

Parkinson's disease (PD) is the second most common neurodegenerative disease worldwide, with the incidence in men being about twice as compared to women. Gender differences may provide clues for finding key targets that mediate the death of dopaminergic (DA) neurons in PD. Luteinizing hormone (LH), analog of human chorionic gonadotropin (hCG), and their receptor, luteinizing hormone/choriogonadotropin receptor (LHCGR), are associated with the pathogenesis of PD. Movement-related symptoms are partially improved by hCG in PD patients. However, the relationship between hCG and PD, as well as its roles in mediating DA neuronal death, has not been elucidated. In this study, we investigated the potential of hCG as a treatment during PD progression. After establishment of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced PD mouse models, we found that hCG restored the decrease of LHCGR activity caused by down-regulation of LH in the substantia nigra. Furthermore, the reduction of LHCGR activity led to DA neuronal death through knocking down the LHCGR in DA neurons by AAV-mTH-shRNA. Treatment with hCG alleviated the DA neuronal death induced by MPTP. Finally, hCG exerted neuroprotective effects by inhibiting the activation of glycogen synthase kinase 3 beta (GSK3ß) in our MPTP-induced PD mouse and MPP+-treated SH-SY5Y cell models. Together, these results demonstrate that hCG exerts neuroprotective effects for PD through LHCGR, and the inhibition of GSK3ß activation is involved in this protective effect, suggesting that hCG can be taken as a potential therapeutic for the treatment of PD.


Asunto(s)
Neuroblastoma , Enfermedades Neurodegenerativas , Fármacos Neuroprotectores , Enfermedad de Parkinson , 1-Metil-4-fenil-1,2,3,6-Tetrahidropiridina/farmacología , Animales , Gonadotropina Coriónica/farmacología , Modelos Animales de Enfermedad , Neuronas Dopaminérgicas/patología , Femenino , Glucógeno Sintasa Quinasa 3 beta , Humanos , Ratones , Ratones Endogámicos C57BL , Neuroblastoma/patología , Enfermedades Neurodegenerativas/tratamiento farmacológico , Fármacos Neuroprotectores/farmacología , Fármacos Neuroprotectores/uso terapéutico , Enfermedad de Parkinson/tratamiento farmacológico , Enfermedad de Parkinson/patología , Sustancia Negra/patología
4.
Gastrointest Endosc ; 91(4): 932-942, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-31738926

RESUMEN

BACKGROUND AND AIMS: Studies comparing the diagnostic efficacy of liquid-based cytology (LBC) and smear cytology (SC) of pancreatic tissue sampling obtained via EUS-guided FNA (EUS-FNA) are still insufficient, mainly because results were controversial. We compared the diagnostic efficiency of LBC and SC of EUS-FNA of pancreatic lesions in one of the largest tertiary hospitals in China. METHODS: A retrospective database search (January 2015 to January 2019) was performed for patients who underwent EUS-FNA with both LBC and SC. Demographic, cytologic, and endosonographic data were collected from 819 patients; 514 cases met the inclusion criteria. Diagnostic accuracy, sensitivity, specificity, positive predictive value, and negative predictive value were compared. Rapid on-site evaluation was not available in all cases. RESULTS: Three hundred eighty-five cases (74.90%) had confirmed malignancy, and 40 cases (7.78%) confirmed benign neoplasm. Adequate tissue sampling rates showed no significant difference between the 2 groups. The sensitivity, accuracy, and negative predictive value (NPV) of LBC were higher than those of SC with statistical significance (71.4% vs 55.1%, 76.1% vs 61.6%, and 40.6% vs 27.7%, respectively). The sensitivity, accuracy, and NPV of combined SC and LBC were higher than those of LBC alone with statistical significance (83.9% vs 71.4%, 86.5% vs 76.1%, and 56.8% vs 40.6%, respectively). Multivariate analysis revealed that pancreatic neck/body/tail lesions (P = .003), solid lesions (P < .001), 22-gauge needle size (P < .001), and number of needle passage >3 (P = .041) were associated with higher diagnostic sensitivity in all participants using LBC, whereas number of needle passage >3 (P = .017) was associated with higher diagnostic sensitivity using SC. CONCLUSIONS: LBC was more accurate and sensitive than SC in EUS-FNA of pancreatic lesions with higher NPV when rapid on-site evaluation is unavailable. Pancreatic neck/body/tail lesions, solid lesions, 22-gauge needle, and more than 3 passes were associated with higher sensitivity when using LBC. Performing more than 3 passes is associated with higher sensitivity when using SC.


Asunto(s)
Biopsia por Aspiración con Aguja Fina Guiada por Ultrasonido Endoscópico , China , Humanos , Páncreas/diagnóstico por imagen , Neoplasias Pancreáticas/diagnóstico por imagen , Estudios Retrospectivos , Centros de Atención Terciaria
5.
Org Biomol Chem ; 16(35): 6491-6498, 2018 09 11.
Artículo en Inglés | MEDLINE | ID: mdl-30155541

RESUMEN

Enabled by nickel catalysis, a practical access to the synthesis of 4-benzyl-3,3-difluoro-γ-lactams has been developed via radical tandem cyclisation/arylation. This method features a nickel catalyst, high reaction efficiency, and good substrate tolerance and scope. This protocol proceeds through an intramolecular radical addition to form a primary alkyl radical followed by intermolecular Suzuki-type coupling.

6.
Nephrology (Carlton) ; 19(3): 129-35, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24397346

RESUMEN

AIM: Early intervention in patients with chronic kidney disease (CKD) significantly improves the prognosis. The present widely used markers of renal function, such as serum creatinine (sCr), fail to reflect early renal damage and predict the progression of disease. The authors aimed to evaluate whether neutrophil gelatinase-associated lipocalin (NGAL), a novel specific biomarker of acute kidney injury, could predict the progression of CKD. METHODS: We identified 92 patients with stage 2-4 CKD caused by primary chronic glomerulonephritis. The patients were followed for 2 years, the changes in NGAL levels in the progressive and non-progressive groups were compared. RESULTS: First, the serum NGAL levels of patients with stage 2-4 CKD were significantly increased compared with the control group. Second, based on Pearson correlation analysis, positive correlations existed between NGAL and cystatin C levels and between NGAL and sCr levels. Third, bounded by the progress of renal function, the area under the curve of serum NGAL was 0.872 (95% confidence interval, 0.786-0.933), which suggests a blood NGAL cut-off level of 246 ng/mL (sensitivity 85.19%, specificity 81.54%). Fourth, Kaplan-Meier survival curve analysis showed that the serum NGAL level was closely related to the end-point of renal function in patients with CKD. Fifth, Cox multivariate regression analysis showed that the estimated glomerular filtration rate and blood NGAL are associated with progression of CKD. CONCLUSION: Serum NGAL is an effective biomarker for detecting early-stage renal damage in CKD patients. Serum NGAL was significantly correlated with the severity of renal damage and the progression of renal function deterioration.


Asunto(s)
Cistatina C/sangre , Lipocalinas/sangre , Proteínas Proto-Oncogénicas/sangre , Insuficiencia Renal Crónica/sangre , Proteínas de Fase Aguda , Adulto , Anciano , Creatinina/sangre , Femenino , Tasa de Filtración Glomerular , Humanos , Lipocalina 2 , Masculino , Persona de Mediana Edad , Modelos de Riesgos Proporcionales , Insuficiencia Renal Crónica/mortalidad , Insuficiencia Renal Crónica/fisiopatología
7.
Adv Sci (Weinh) ; 11(22): e2400615, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38489666

RESUMEN

Selenium (Se), the world's oldest optoelectronic material, has been widely applied in various optoelectronic devices such as commercial X-ray flat-panel detectors and photovoltaics. However, despite the rare and widely-dispersed nature of Se element, a sustainable recycling of Se and other valuable materials from spent Se-based devices has not been developed so far. Here a sustainable strategy is reported that makes use of the significantly higher vapor pressure of volatile Se compared to other functional layers to recycle all of them from end-of-life Se-based devices through a closed-space evaporation process, utilizing Se photovoltaic devices as a case study. This strategy results in high recycling yields of ≈ 98% for Se and 100% for other functional materials including valuable gold electrodes and glass/FTO/TiO2 substrates. The refabricated photovoltaic devices based on these recycled materials achieve an efficiency of 12.33% under 1000-lux indoor illumination, comparable to devices fabricated using commercially sourced materials and surpassing the current indoor photovoltaic industry standard of amorphous silicon cells.

8.
ACS Sens ; 9(3): 1545-1554, 2024 03 22.
Artículo en Inglés | MEDLINE | ID: mdl-38450702

RESUMEN

rRNAs are prevalent in living organisms. They are produced in nucleolus and mitochondria and play essential cellular functions. In addition to the primary biofunction in protein synthesis, rRNAs have been recognized as the emerging signaling molecule and drug target for studies on nucleolus morphology, mitochondrial autophagy, and tumor cell malignancy. Currently, only a few rRNA-selective probes have been developed, and most of them encounter the drawbacks of low water solubility, poor nuclear membrane permeability, short emission wavelength, low stability against photobleaching, and high cytotoxicity. These unfavorable properties of rRNA probes limit their potential applications. In the present study, we reported a new rRNA-selective and near-infrared fluorescent turn-on probe, 4MPS-TO, capable of tracking rRNA in live human cancer cells. The real-time monitoring performance in nucleolus morphology and mitochondrial autophagy is demonstrated in HeLa cells. The probe shows great application potential for being used as a rRNA-selective, sensitive, and photostable imaging tool in chemical biology study and drug screening.


Asunto(s)
Mitofagia , Neoplasias , Humanos , Células HeLa , Colorantes Fluorescentes/química , Imagen Óptica/métodos , Autofagia
9.
Oncol Res ; 20(10): 473-82, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24308158

RESUMEN

Heme oxygenase-1 [HO-1, also called heat shot protein 32 (HSP32)] can specifically metabolize heme to carbon monoxide, biliverdin, and ferrous iron and plays an important role in the processes of anti-inflammation, tissue protection, and antioxidative stress reaction. It has been reported that HO-1 can promote tumorigenesis and metastasis of many tumors. However, the detailed mechanisms of how HO-1 affects tumor progress are not clear. Here, we used ZnPPIX (a specific inhibitor of HO-1) to evaluate its potential effects on mouse breast cancer and tumor-associated macrophages (TAMs). We found out that mouse 4T1 breast cancer growth can be effectively suppressed through inhibition of HO-1 in vitro and in vivo. Moreover, in the 4T1 mouse model, when HO-1 was suppressed in TAMs, alternatively activated macrophages (M2 type) switched to classically activated macrophages (M1 type). In conclusion, 4T1 breast cancer growth was modulated by HO-1 expression. Furthermore, inhibition of HO-1 may induce tumor-associated immune response by activating TAMs' alternative proliferation. These data suggest that HO-1 may be an important target of breast cancer treatment.


Asunto(s)
Antineoplásicos/farmacología , Neoplasias de la Mama/tratamiento farmacológico , Inhibidores Enzimáticos/farmacología , Hemo-Oxigenasa 1/antagonistas & inhibidores , Macrófagos/efectos de los fármacos , Neoplasias Mamarias Experimentales/tratamiento farmacológico , Proteínas de la Membrana/antagonistas & inhibidores , Protoporfirinas/farmacología , Animales , Apoptosis/efectos de los fármacos , Neoplasias de la Mama/enzimología , Neoplasias de la Mama/patología , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Femenino , Hemo-Oxigenasa 1/metabolismo , Activación de Macrófagos/efectos de los fármacos , Macrófagos/enzimología , Macrófagos/patología , Neoplasias Mamarias Experimentales/enzimología , Neoplasias Mamarias Experimentales/patología , Proteínas de la Membrana/metabolismo , Ratones , Ratones Endogámicos BALB C , Necrosis , Factores de Tiempo , Carga Tumoral/efectos de los fármacos
10.
Acta Pharmacol Sin ; 34(2): 221-30, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23202797

RESUMEN

AIM: To study the effects of Na(+) channel blocker flecainide and L-type Ca(2+) channel antagonist verapamil on the voltage-gated fKv1.4ΔN channel, an N-terminal-deleted mutant of the ferret Kv1.4 K(+) channel. METHODS: fKv1.4ΔN channels were stably expressed in Xenopus oocytes. The K(+) currents were recorded using a two-electrode voltage-clamp technique. The drugs were administered through superfusion. RESULTS: fKv1.4ΔN currents displayed slow inactivation, with a half-inactivation potential of -41.74 mV and a slow recovery from inactivation (τ=1.90 s at -90 mV). Flecainide and verapamil blocked the currents with IC(50) values of 512.29 ± 56.92 and 260.71 ± 18.50 µmol/L, respectively. The blocking action of the drugs showed opposite voltage-dependence: it was enhanced with depolarization for flecainide, and was attenuated with depolarization for verapamil. Both the drugs exerted state-dependent blockade on fKv1.4ΔN currents, but verapamil showed a stronger use-dependent blockage compared with flecainide. Flecainide accelerated the C-type inactivation rate without affecting the recovery kinetics and the steady-state activation. Verapamil also accelerated the inactivation kinetics of the currents, but unlike flecainide, it affected both the recovery and the steady-state activation, causing slower recovery of fKv1.4ΔN channel and a depolarizing shift of the steady-state activation curve. CONCLUSION: The results demonstrate that widely used antiarrhythmic drugs flecainide and verapamil substantially inhibit fKv1.4ΔN channels expressed in Xenopus oocytes by binding to the open state of the channels. Therefore, caution should be taken when these drugs are administered in combination with K(+) channel blockers to treat arrhythmia.


Asunto(s)
Antiarrítmicos/farmacología , Flecainida/farmacología , Canal de Potasio Kv1.4/antagonistas & inhibidores , Canal de Potasio Kv1.4/metabolismo , Oocitos/efectos de los fármacos , Verapamilo/farmacología , Animales , Células Cultivadas , Femenino , Expresión Génica , Canal de Potasio Kv1.4/genética , Mutación , Oocitos/metabolismo , Xenopus
11.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 6): o1817, 2012 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-22719589

RESUMEN

The title compound, C(17)H(12)N(2)O·H(2)O, was synthesized by the reaction of 4,5-diaza-fluoren-9-one with a Grignard reagent in ether (the reaction mixture being hydrolysed with saturated NH(4)Cl solution), and crystallizes with two organic mol-ecules and two water mol-ecules in the asymmetric unit. The 4,5-diaza-fluorene fragment is approximately planar, with r.m.s. deviations of 0.0448 and 0.0198 Šin the two mol-ecules. The dihedral angles between the 4,5-diaza-fluorene planes and the phenyl ring are 80.49 (6) and 76.57 (7)°. The crystal packing features O-H⋯N and O-H⋯O hydrogen bonds involving the bridging solvent water mol-ecules, which link the mol-ecules into a three-dimensional network.

12.
J Immunol Res ; 2022: 8025055, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36052280

RESUMEN

One of the most prevalent malignant primary brain tumors is primary glioma. Although glutathione peroxidase 8 (GPX8) is intimately associated with carcinogenesis, its function in primary gliomas has not yet been thoroughly understood. Here, we leveraged Chinese Glioma Genome Atlas (CGGA), The Cancer Genome Atlas (TCGA), and Genotype-Tissue Expression (GTEx) database to investigate the association between GPX8 and overall survival (OS) of patients with primary gliomas, and our results showed that GPX8 expression was negatively correlated with OS. Moreover, the expression of GPX8 is significantly lower in normal tissue when compared to glioma tissue. According to results of univariate and multivariate analysis from CGGA using R studio, GPX8 is a valuable primary glioma prognostic indicator. Interestingly, high GPX8 expression is correlated positively with the hedgehog and kras signaling pathways and negatively with G2 checkpoint, apoptosis, reactive oxygen species (ROS) pathway, and interferon gamma pathway, which could be beneficial for the proliferation of glioma cells. Furthermore, GPX8 knockdown caused G1 cell cycle arrest, increased cell death, and reduced colony formation in U87MG and U118MG cells. In conclusion, GPX8 is a promising therapeutic target and meaningful prognostic biomarker of primary glioma.


Asunto(s)
Neoplasias Encefálicas , Glioma , Peroxidasas , Apoptosis/genética , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patología , Carcinogénesis , Glioma/genética , Glioma/metabolismo , Glioma/terapia , Humanos , Peroxidasas/genética , Pronóstico
13.
Acta Pharmacol Sin ; 32(4): 465-77, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21468083

RESUMEN

AIM: To investigate the effects of diltiazem, an L-type calcium channel blocker, and propafenone, a sodium channel blocker, on the inactivation and recovery kinetics of fKv1.4, a potassium channel that generates the cardiac transient outward potassium current. METHODS: The cRNA for fKv1.4ΔN, an N-terminal deleted mutant of the ferret Kv1.4 potassium channel, was injected into Xenopus oocytes to express the fKv1.4ΔN channel in these cells. Currents were recorded using a two electrode voltage clamp technique. RESULTS: Diltiazem (10 to 1000 µmol/L) inhibited the fKv1.4ΔN channel in a frequency-dependent, voltage-dependent, and concentration-dependent manner, suggesting an open channel block. The IC(50) was 241.04±23.06 µmol/L for the fKv1.4ΔN channel (at +50 mV), and propafenone (10 to 500 µmol/L) showed a similar effect (IC(50)=103.68±10.13 µmol/L). After application of diltiazem and propafenone, fKv1.4ΔN inactivation was bi-exponential, with a faster drug-induced inactivation and a slower C-type inactivation. Diltiazem increased the C-type inactivation rate and slowed recovery in fKv1.4ΔN channels. However, propafenone had no effect on either the slow inactivation time constant or the recovery. CONCLUSION: Diltiazem and propafenone accelerate the inactivation of the Kv1.4ΔN channel by binding to the open state of the channel. Unlike propafenone, diltiazem slows the recovery of the Kv1.4ΔN channel.


Asunto(s)
Fármacos Cardiovasculares/farmacología , Diltiazem/farmacología , Canal de Potasio Kv1.4/antagonistas & inhibidores , Propafenona/farmacología , Animales , Femenino , Concentración 50 Inhibidora , Cinética , Canal de Potasio Kv1.4/genética , Canal de Potasio Kv1.4/metabolismo , Proteínas Recombinantes/antagonistas & inhibidores , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Xenopus
14.
Acta Crystallogr Sect E Struct Rep Online ; 67(Pt 10): m1343, 2011 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-22065644

RESUMEN

In the title compound, [Ir(C(18)H(12)NO(2))(2)(C(5)H(7)O(2))], the Ir atom is O,O'-chelated by the acetyl-acetonate group and C,N-chelated by the 2-aryl-naphth[1,2-d]oxazole groups. The six-coordinate metal atom displays a distorted octa-hedral geometry. Intra-molecular C-H⋯O hydrogen bonds occur. In the crystal, inter-molecular C-H⋯O hydrogen bonds link the mol-ecules into columns parallel to the b axis.

15.
Guang Pu Xue Yu Guang Pu Fen Xi ; 29(4): 1036-40, 2009 Apr.
Artículo en Zh | MEDLINE | ID: mdl-19626898

RESUMEN

Valuable achievements on differential optical absorption spectroscopy (DOAS) for monitoring atmospheric pollutants gas have been made in the past decades. Based on the idea of setting the threshold according to the maximum value, symbolized as OD'm, of differential optical density, the algorithm of traditional DOAS was combined with the DOAS algorithm based on the kalman filtering to improve the detection limit without losing measurement accuracy in the present article. Two algorithms have different inversion accuracy at the same ratio of signal to noise and the problem of inversion accuracy was well resolved by combining two algorithms at short light path length. Theoretical and experimental research on the concentration measurement of SO2 in the flue gases was carried out at the normal temperature and atmospheric pressure. The research results show that with the OD'm less than 0.0481, the measurement precision is very high for SO2 with the improved DOAS algorithm. The measurement lower limit of SO2 is less than 28.6 mg x m(-3) and the zero drift of the system is less than 2.9 mg x m(-3). If the OD'm is between 0.0481 and 0.9272, the measurement precision is high with the traditional DOAS algorithm. However, if the OD'm is more than 0.922, the errors of measurement results for both two DOAS algorithms are very large and the linearity correction must be performed.

16.
Zhonghua Yi Xue Za Zhi ; 88(17): 1185-8, 2008 Apr 29.
Artículo en Zh | MEDLINE | ID: mdl-18844113

RESUMEN

OBJECTIVE: To investigate the association between two estrogen receptor (ER) beta gene polymorphisms and Parkinson disease (PD) as well as Parkinson disease with dementia (PDD) in Chinese people. METHODS: Peripheral blood samples were collected from 115 PD patients (including 26 PDD cases), 56 males and 55 females, aged 64 +/- 10, and 116 sex and age-matched healthy controls. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method was used to analyze the polymorphism of the fifth exon RsaI and the eighth exon AluI of ERbeta gene. Te relationship between each genotype or allele frequencies and PD/PDD was analyzed using chi-square test. RESULTS: There was no difference in the polymorphism of ERbeta genes AluI and Rsa I between the PD group and control group and between the PDD group and control group (all P > 0.05). CONCLUSION: Genetic variations from AluI and RsaI digestion in ERbeta gene do not affect the risk of PD and PDD.


Asunto(s)
Receptor beta de Estrógeno/genética , Enfermedad de Parkinson/genética , Polimorfismo Genético , Anciano , Secuencia de Bases , Estudios de Casos y Controles , Distribución de Chi-Cuadrado , Femenino , Frecuencia de los Genes , Genotipo , Humanos , Masculino , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa , Polimorfismo de Longitud del Fragmento de Restricción
17.
ACS Nano ; 11(10): 10330-10336, 2017 10 24.
Artículo en Inglés | MEDLINE | ID: mdl-28933813

RESUMEN

Carbon fiber is a good candidate in various applications, including in the military, structural, sports equipment, energy storage, and infrastructure. Coloring of carbon fiber has been a big challenge for decades due to their high degrees of crystallization and insufficient chemical affinity to dyes. Here, multicolored carbon fiber fabrics are fabricated using a feasible and effective atomic layer deposition (ALD) technique. The vibrant and uniform structural colors originating from thin-film interference is simply regulated by controlling the thickness of conformal TiO2 coatings on the surface of black carbon fibers. Impressively, the colorful coatings show excellent laundering durability, which can endure 50 cycles of domestic launderings. Moreover, the mechanical properties only drop off slightly after coloring. Overall, these results open an alternative avenue for development of TiO2 nanostructured films with multifunctional features grown using ALD technologies. This technology is speculated to have potential applications in various fields such as color engineering and radiation-proof fabrics and will further guide material design for future innovations in functional optical and color-display devices. More importantly, this research demonstrates a route for the coloring of black carbon fiber-based materials with vibrant colors.

18.
J Chromatogr A ; 1129(2): 255-61, 2006 Oct 06.
Artículo en Inglés | MEDLINE | ID: mdl-16846607

RESUMEN

The thermodynamic properties of poly(methyl methacrylate-co-butyl acrylate-co-cyclo -pentylstyryl polyhedral oligomeric silsesquioxane) (poly(MMA-co-BA-co-styryl-POSS)) were investigated by means of inverse gas chromatography (IGC) using 20 different kinds of solvents as the probes. Some thermodynamic parameters, such as molar heats of sorption, weight fraction activity coefficient, Flory-Huggins interaction parameter, partial molar heats of mixing and solubility parameter were obtained to judge the interactions between POSS-contained polymers and solvents and the solubility of the polymers in these solvents. It was found that acetates, aromatic hydrocarbons and hydrocarbon halides were good solvents, n-hexane, ethanol, n-propanol, n-butanol and n-pentanol were moderate solvents, while n-heptane, n-octane, n-nonane, n-decane and methanol were poor solvents for all POSS-contained polymers within the experimental temperature range. Incorporation of POSS in polymer increased the solubility of polymers in solvents, and the more the POSS in polymer was, the better the solubility was and stronger the hydrogen bonding interaction was, but the POSS content in polymers seemed to have no obvious influence on the solubility parameter of polymers.


Asunto(s)
Cromatografía de Gases/métodos , Compuestos de Organosilicio/química , Polimetil Metacrilato/química , Poliestirenos/química , Compuestos de Organosilicio/análisis , Polimetil Metacrilato/análisis , Poliestirenos/análisis , Reproducibilidad de los Resultados , Solubilidad , Solventes/química , Propiedades de Superficie , Termodinámica
19.
J Chromatogr A ; 1110(1-2): 140-5, 2006 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-16460744

RESUMEN

The surface properties of poly(methyl methacrylate-co-n-butyl acrylate-co-cyclopentylstyryl polyhedral oligomeric silsesquioxane) (poly(MMA-co-BA-co-styryl-POSS)) were studied by means of inverse gas chromatography (IGC) using 10 non-polar and polar solvents as the probes. Thermodynamic parameters of adsorption, e.g., specific retention volume, the dispersive component of the surface free energy, the specific interaction contribution to the free energy of adsorption and the acid/base constants were obtained to investigate the interactions between the surfaces of the copolymers and different solvents. It was found that incorporation of styryl-POSS into polymer resulted in increasing interactions between polymers and solvents, dispersive component of surface free energy of polymer and acidity of the surfaces of the polymers. The more the styryl-POSS were embedded, the stronger the interaction between the polymer surface and solvent, the dispersive component of the surface free energy and the acidity of the polymer surface were.


Asunto(s)
Acrilatos/química , Cromatografía de Gases/métodos , Compuestos de Organosilicio/química , Polimetil Metacrilato/química , Poliestirenos/química , Adsorción , Concentración de Iones de Hidrógeno , Solventes/química , Propiedades de Superficie , Termodinámica
20.
Zhonghua Nan Ke Xue ; 11(7): 514-6, 519, 2005 Jul.
Artículo en Zh | MEDLINE | ID: mdl-16078669

RESUMEN

OBJECTIVE: To investigate the objective index of the diagnosis of varicocele (VC) in infertile males by ultrasonography and the testis volume changes resulting from varicocele. METHODS: Forty-six healthy male volunteers and 178 infertile men with left varicocele were detected by high frequency ultrasound. According to the clinical data and ultrasonographic results, the 178 VC patients were divided into 4 groups, SVC group (45 cases), VC I group (44 cases), VC II group (48 cases), and VC III group (41 cases). RESULTS: (1) The differences in DR, DV, Vmax, TR and testis volume between the right and the left sides were not statistically significant in the control group (P > 0.05). (2) The differences in DR, DV, Vmax and TR between the experimental and control groups as well as among the VC groups were statistically significant (P < 0.001). (3) The left testis volume was smaller than the right among the VC groups (P < 0.01). The right testis volume of the VC II and VC III groups was significantly smaller than that of the control group ( P < 0.05), and the left testis volume in the VC III group was significantly smaller than that of the SVC group (P < 0.05). CONCLUSION: (1) High frequency ultrasound can detect the accurate diameter of the internal spermatic vein, hemodynamic index and testis volume of infertile men with VC, and hence help to screen the causes of male infertility. (2) Unilateral varicocele can cause a volume decrease in both testes, especially in the left. Both unilateral SVC and VC can cause testicular atrophy, and the more serious VC, the higher testicular atrophy.


Asunto(s)
Infertilidad Masculina/diagnóstico por imagen , Testículo/diagnóstico por imagen , Varicocele/diagnóstico por imagen , Adulto , Humanos , Masculino , Ultrasonografía Doppler en Color
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