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1.
Langmuir ; 39(39): 13863-13875, 2023 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-37733306

RESUMEN

Co-encapsulated xanthoxylin (GX-50) and vitamin C (Vc) microcapsules (GX-50-Vc-M) were prepared by the combination of a water-in-oil-in-water (W1/O/W2) double emulsion with complex coacervation. The W1/O/W2 double emulsion was prepared by two-step emulsification, and it has a uniform particle size of 8.388 µm and high encapsulation efficiencies of GX-50 (85.95%) and Vc (67.35%) under optimized process conditions. Complex coacervation occurs at pHs 4.0-4.7, which has the highest encapsulation efficiency of GX-50 and Vc at pH 4.5. The complex coacervate with tannic acid solidifying (namely, wet microcapsules) has better mechanical properties and also enhances the ability of co-encapsulation of active ingredients. The resulting microcapsules by freeze-drying of wet microcapsules were characterized by UV-vis absorbance spectroscopy (UV-vis), Fourier infrared spectroscopy (FI-IR), confocal laser scanning microscopy (CLSM), scanning electron microscopy (SEM), X-ray diffraction (XRD), 2,2-diphenyl-1-picrylhydrazyl (DPPH·) radical scavenging, and in vitro permeation measurements. Under optimal conditions, the encapsulation efficiency and drug loading of GX-50-Vc-M for GX-50 and Vc are, respectively, 78.38 ± 0.51 and 59.34 ± 0.56%, and 35.6 ± 0.68 and 29.8 ± 0.92%. A slight shift in the FTIR peak between single GX-50 or Vc and GX-50-Vc-M confirmed the successful co-encapsulation of GX-50 and Vc in microcapsules. GX-50-Vc-M has bridged irregular spherical aggregates, while GX-50 and Vc are, respectively, encapsulated in hydrophobic and hydrophilic cavities of microcapsules in an amorphous dissolved state. GX-50-Vc-M has the highest DPPH· radical scavenging rate of 62.51%, and the scavenging process of GX-50-Vc-M on DPPH· radicals is more in line with the pseudo-second-order kinetic equation model. Moreover, the in vitro permeation of GX-50 and Vc in GX-50-Vc-M can reach maximum values of 40 and 60%, respectively. This concludes that GX-50-Vc-M is a promising delivery system for the penetration of the antioxidant into the deeper layers of the skin for the antioxidant effect.

2.
Anticancer Drugs ; 34(5): 686-689, 2023 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-36206106

RESUMEN

It is relatively rare to achieve a median progression-free survival (PFS) of 40 months with pemetrexed monotherapy maintenance, especially in patients with advanced and severe lung cancer. Here, we reported a case of advanced severe lung adenocarcinoma treated with pemetrexed monotherapy maintenance achieving long survival with a median PFS of 46 months. A 52-year-old female diagnosed with stage IV lung adenocarcinoma was tested for no targeted drug benefit in the driver gene. The patient was financially disadvantaged and could not afford and refused immune checkpoint inhibitor drugs but was in the favor of platinum-based double-drug chemotherapy. After six cycles of effective administration of cisplatin in combination with pemetrexed, pemetrexed monotherapy was given for long-term maintenance treatment to date, with a median PFS of 46 months, with a treatment effect close to complete response and tolerable side effects.


Asunto(s)
Adenocarcinoma del Pulmón , Antineoplásicos , Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Femenino , Humanos , Preescolar , Pemetrexed , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Supervivencia sin Enfermedad , Neoplasias Pulmonares/tratamiento farmacológico , Cisplatino , Antineoplásicos/uso terapéutico , Adenocarcinoma del Pulmón/tratamiento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico
3.
Int J Mol Sci ; 25(1)2023 Dec 26.
Artículo en Inglés | MEDLINE | ID: mdl-38203496

RESUMEN

Diapause, an adaptative strategy for survival under harsh conditions, is a dynamic multi-stage process. Bombus terrestris, an important agricultural pollinator, is declining in the wild, but artificial breeding is possible by imitating natural conditions. Mated queen bees enter reproductive diapause in winter and recover in spring, but the regulatory mechanisms remain unclear. Herein, we conducted a comparative 4D label-free proteomic analysis of queen bees during artificial breeding at seven timepoints, including pre-diapause, diapause, and post-diapause stages. Through bioinformatics analysis of proteomic and detection of substance content changes, our results found that, during pre-diapause stages, queen bees had active mitochondria with high levels of oxidative phosphorylation, high body weight, and glycogen and TAG content, all of which support energy consumption during subsequent diapause. During diapause stages, body weight and water content were decreased but glycerol increased, contributing to cold resistance. Dopamine content, immune defense, and protein phosphorylation were elevated, while fat metabolism, protein export, cell communication, signal transduction, and hydrolase activity decreased. Following diapause termination, JH titer, water, fatty acid, and pyruvate levels increased, catabolism, synaptic transmission, and insulin signaling were stimulated, ribosome and cell cycle proteins were upregulated, and cell proliferation was accelerated. Meanwhile, TAG and glycogen content decreased, and ovaries gradually developed. These findings illuminate changes occurring in queen bees at different diapause stages during commercial production.


Asunto(s)
Diapausa , Proteómica , Abejas , Animales , Peso Corporal , Glucógeno , Agua
4.
Environ Geochem Health ; 45(5): 2213-2228, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-35869374

RESUMEN

Exposure to air pollution during pregnancy has been linked to birth defects. But the directions of studies on the associations between air pollutants exposure and effect on the incidence of congenital heart disease (CHDs) were inconsistent. To date, few studies were concentrated on the effects of both particulate matter and gaseous air pollutant exposure on CHDs across the full gestational week simultaneously. Our study aimed to investigate the critical exposure windows for each air pollutant throughout 40 gestational weeks. Data on CHDs, air pollution, and meteorological factors from 2013 to 2019 were collected in Lanzhou, China. A distributed lag nonlinear model combined with a quasi-Poisson regression model was applied to evaluate the weekly exposure-lag-response association between air pollutants levels and CHDs, and the subgroup analyses were conducted by gender (baby boy and baby girl). The study included 1607 mother-infant pairs. The results demonstrated that exposure of pregnant women to particulate matter ≤ 5 µm (PM2.5) at lag 1-4 weeks was significantly associated with the risk of CHDs, and the strongest effects were observed in the lag 1 week (1.150, 95%CI 1.059-1.248). For exposure to particulate matter ≤ 10 µm (PM10) at lag 1-3 weeks, the strongest effects were observed in the lag 1 week (1.075, 95% CI 1.026-1.128). For exposure to sulfur dioxide (SO2) at lag 1-4 weeks, the strongest effects were observed in the lag 1 week (1.154, 95% CI 1.025-1.299). For exposure to carbon monoxide (CO) at lag 1-3 weeks, the strongest effects were observed in the lag 1 week (1.089, 95% CI 1.002-1.183). For exposure to ozone (O3) concentration at lag 9-15 weeks, the strongest effects were observed in the lag 15 weeks (1.628, 95% CI 1.001-2.649). The cumulative effects of PM2.5, PM10, SO2, and CO along weeks with a maximum of 1.609 (95%CI 1.000-2.589), 1.286 (95%CI 1.007-1.641), 1.648 (95%CI 1.018-2.668), and 1.368 (95%CI 1.003, 1.865), respectively. The effects were obvious in the initial gestational weeks too. Through the gender stratification analysis, the air pollutants with significant effects were PM2.5 for baby boys and PM2.5, PM10, SO2, CO, NO2, and O3 for baby girl. For the relationship between CHDs and air pollution in Lanzhou, PM2.5, PM10, SO2, CO, and O3 played an important role in the initial gestational weeks, especially for baby girl.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Cardiopatías Congénitas , Masculino , Lactante , Humanos , Femenino , Embarazo , Contaminantes Atmosféricos/toxicidad , Contaminantes Atmosféricos/análisis , Contaminación del Aire/efectos adversos , Contaminación del Aire/análisis , Material Particulado/toxicidad , Material Particulado/análisis , Dióxido de Azufre/toxicidad , Dióxido de Azufre/análisis , Cardiopatías Congénitas/inducido químicamente , Cardiopatías Congénitas/epidemiología , China/epidemiología
5.
Plant Cell Environ ; 45(8): 2395-2409, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35610189

RESUMEN

Thylakoid FtsH complex participates in PSII repair cycle during high light-induced photoinhibition. The Arabidopsis yellow variegated2 (var2) mutants are defective in the VAR2/AtFtsH2 subunit of thylakoid FtsH complex. Taking advantage of the var2 leaf variegation phenotype, dissections of genetic enhancer loci have yielded novel paradigms in understanding functions of thylakoid FtsH complex. Here, we report the isolation of a new var2 enhancer, enhancer of variegation2-1 (evr2-1). We confirmed that EVR2 encodes a chloroplast protein that was known as BALANCE OF CHLOROPHYLL METABOLISM 1 (BCM1), or CHLOROPHYLL BIOSYNTHETIC DEFECT 1 (CBD1). We showed that EVR2/BCM1/CBD1 was involved in the oligomerization of photosystem I complexes. Genetic assays indicated that general defects in chlorophyll biosynthesis and the accumulation of photosynthetic complexes do not necessarily enhance var2 leaf variegation. In addition, we found that VAR2/AtFtsH2 is required for the accumulation of photosynthetic proteins during de-etiolation. Moreover, we identified PSII core proteins D1 and PsbC as potential EVR2-associated proteins using Co-IP/MS. Furthermore, the accumulation of D1 protein was greatly compromised in the var2-5 evr2-1 double mutant during de-etiolation. Together, our findings reveal a functional link between VAR2/AtFtsH2 and EVR2/BCM1/CBD1 in regulating chloroplast development and the accumulation of PSII reaction centre D1 protein during de-etiolation.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Proteasas ATP-Dependientes/genética , Proteasas ATP-Dependientes/metabolismo , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Clorofila/metabolismo , Cloroplastos/metabolismo , Etiolado , Proteínas de la Membrana/metabolismo , Mutación/genética , Complejo de Proteína del Fotosistema II/metabolismo
6.
Sensors (Basel) ; 23(1)2022 Dec 30.
Artículo en Inglés | MEDLINE | ID: mdl-36617033

RESUMEN

An electrochemical sensor enabled by electropolymerization (EP) of ß-cyclodextrin on glassy carbon electrode (ß-CDP/GCE) is built for the determination of fenitrothion (FNT). The effects of the EP cycles, pH value, and enrichment time on the electrochemical response of FNT were studied. With the optimum conditions, good linear relationships between the current of the reduction peak of the nitroso derivative of FNT and the concentration are obtained in the range of 10-150 and 150-4000 ng/mL, with a detection limit of 6 ng/mL (S/N = 3). ß-CDP/GCE also exhibits a satisfactory applicability in cabbage and tap water, with recovery values between 98.43% and 112%. These outstanding results suggest that ß-CDP/GCE could be a new effective alternative for the determination of FNT in real samples.


Asunto(s)
Carbono , beta-Ciclodextrinas , Fenitrotión , Técnicas Electroquímicas/métodos , Electrodos
7.
Microvasc Res ; 135: 104130, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33385382

RESUMEN

The aberrant increase of circulating beta-human chorionic gonadotropin (ß-HCG) at early stages of pregnancy can be used to predict gestational hypertension. However, the association of ß-HCG and inflammation, oxidative stress in pregnancy-caused hypertensive disorder on perinatal stage remains unclear. A case-controlled study was performed, with 133 adult pregnant women participated in their perinatal stage. Participants in this research included 45 with mild preeclampsia, 40 with severe preeclampsia and 48 without hypertension. Higher circulating ß-HCG level was correlated with severer pregnancy-induced hypertension. Independent contribution of inflammatory factors including interleukin-6, tumor necrosis factor-α and interferon-γ and oxidative stress factors including thiobarbituric acid reactive substance and total antioxidant capacity to severe pregnancy-induced hypertension was significant (P < 0.001). The correlation of circulating ß-HCG levels with inflammatory and oxidative stress markers in patients with pregnancy-induced hypertension in perinatal stage was statistically significant.


Asunto(s)
Gonadotropina Coriónica Humana de Subunidad beta/sangre , Mediadores de Inflamación/sangre , Estrés Oxidativo , Preeclampsia/sangre , Adulto , Biomarcadores/sangre , Presión Sanguínea , Estudios de Casos y Controles , Femenino , Humanos , Preeclampsia/diagnóstico , Preeclampsia/fisiopatología , Embarazo , Índice de Severidad de la Enfermedad , Adulto Joven
8.
Biometals ; 34(1): 33-48, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33033991

RESUMEN

This study aims to explore the protective effects of quercetin against cadmium-induced nephrotoxicity utilizing metabolomics methods. Male Sprague-Dawley rats were randomly assigned to six groups: control, different dosages of quercetin (10 and 50 mg/kg·bw, respectively), CdCl2 (4.89 mg/kg·bw) and different dosages quercetin plus CdCl2 groups. After 12 weeks, the kidneys were collected for metabolomics analysis and histopathology examination. In total, 11 metabolites were confirmed, the intensities of which significantly changed (up-regulated or down-regulated) compared with the control group (p < 0.00067). These metabolites include xanthosine, uric acid (UA), guanidinosuccinic acid (GSA), hypoxanthine (Hyp), 12-hydroxyeicosatetraenoic acid (tetranor 12-HETE), taurocholic acid (TCA), hydroxyphenylacetylglycine (HPAG), deoxyinosine (DI), ATP, formiminoglutamic acid (FIGLU) and arachidonic acid (AA). When high-dose quercetin and cadmium were given to rats concurrently, the intensities of above metabolites significantly restored (p < 0.0033 or p < 0.00067). The results showed quercetin attenuated Cd-induced nephrotoxicity by regulating the metabolism of lipids, amino acids, and purine, inhibiting oxidative stress, and protecting kidney functions.


Asunto(s)
Riñón/metabolismo , Metabolómica , Sustancias Protectoras/metabolismo , Quercetina/metabolismo , Animales , Cadmio/toxicidad , Relación Dosis-Respuesta a Droga , Inyecciones Intraperitoneales , Riñón/efectos de los fármacos , Riñón/patología , Masculino , Estrés Oxidativo/efectos de los fármacos , Sustancias Protectoras/administración & dosificación , Sustancias Protectoras/farmacología , Quercetina/administración & dosificación , Quercetina/farmacología , Ratas , Ratas Sprague-Dawley
9.
BMC Cardiovasc Disord ; 20(1): 510, 2020 12 04.
Artículo en Inglés | MEDLINE | ID: mdl-33276720

RESUMEN

BACKGROUND: Percutaneous coronary intervention (PCI) is a common treatment for patients with coronary heart disease, and intra-stent restenosis (ISR) is a serious complication after PCI. It's necessary to identify the potential risk factors to provide evidence for the prevention of ISR. METHODS: The patients who underwent coronary angiography 1 year after PCI in our hospital from January 2017 to May 2019 were selected. The characteristics and results of clinical examination of ISR and no-ISR patients were compared, Multivariate logistic regression analyses were performed to identify the risk factors. RESULTS: A total of 209 patients were included, the incidence of ISR after PCI was 30.62%. There were significant differences on the hypertension, diabetes, number of coronary artery lesions, reasons for stent implantation, the diameter of stent, the length of stent and stent position between ISR group and no-ISR patients (all p < 0.05). The LDL-C in ISR groups was significantly higher than that of no-ISR group (p = 0.048), there were no significant differences between two groups in FPG, TG, TC, HDL-C, Apo A1, Apo B, LP-a and glycated haemoglobin (all p > 0.05). The hypertension (OR 4.30, 95% CI 1.12-9.34), diabetes (OR 5.29, 95% CI 1.25-9.01), number of coronary artery lesions ≥ 2 (OR 4.84, 95% CI 1.21-9.55), LDL-C ≥ 1.9 mmol/L (OR 5.93, 95% CI 2.29-10.01), unstable angina (OR 2.92, 95% CI 1.20-4.55), left anterior descending artery (OR 4.01, 95% CI 1.73-7.58), diameter of stent ≥ 3 mm (OR 5.42, 95% CI 1.24-10.84), the length of stent > 20 mm (OR 3.06, 95% CI 1.19-5.22) were the independent risk factor for ISR (all p < 0.05). CONCLUSION: It is necessary to take preventive measures against these risk factors to reduce ISR, and studies with larger sample size and longer follow-up on this issue are needed in the future.


Asunto(s)
Enfermedad de la Arteria Coronaria/terapia , Reestenosis Coronaria/epidemiología , Intervención Coronaria Percutánea/efectos adversos , Intervención Coronaria Percutánea/instrumentación , Stents , Anciano , China/epidemiología , Angiografía Coronaria , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Enfermedad de la Arteria Coronaria/epidemiología , Reestenosis Coronaria/diagnóstico por imagen , Reestenosis Coronaria/prevención & control , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Medición de Riesgo , Factores de Riesgo , Factores de Tiempo , Resultado del Tratamiento
10.
Heart Vessels ; 35(11): 1494-1501, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32449048

RESUMEN

Retinol-binding protein-4 (RBP-4) along with the lipid profile plays crucial roles in Acute coronary syndrome (ACS). The study aimed to investigate the correlation of RBP-4, lipoprotein combine index (LCI), and RBP-4 + LCI with ACS. 163 ACS and 77 non-CAD in patients were consecutively enrolled in this study. The serum level of RBP-4 was measured via enzyme-linked immunosorbent assay. LCI was calculated using the formula: total cholesterol × triglyceride × low-density lipoprotein cholesterol/high-density lipoprotein cholesterol. RBP-4 ≥4 ng/ml, LCI ≥16 and LCI ≥16 + RBP-4 ≥4 ng/ml were new independent risk factors of ACS, and OR value of LCI ≥16 + RBP-4 ≥4 ng/ml was higher than that of RBP-4 and LCI combined (all p < 0.05). The AUC for LCI + RBP-4 was higher than that for LCI and RBP-4 individually. The risk of high LCI in 1 lesion vessel was greater than those of 2 or ≥3 lesion vessels (all p < 0.05). In 1 lesion vessel or ≥3 lesion vessels group, the risk associated with LCI and RBP-4 combined was higher than the risk of LCI or RBP-4 alone (all p < 0.05). The risk of hypertension, diabetes mellitus, smoking and history of MI increased with numbers of vessels lesion (all p < 0.05). Increase in RBP-4 and LCI values were found to be independent risk factors for ACS, and the risk of the combined rise in LCI and RBP-4 values was higher than LCI or RBP-4 alone. The combined tests of LCI and RBP-4 might be a potential diagnostic marker for ACS.


Asunto(s)
Síndrome Coronario Agudo/sangre , Lipoproteínas/sangre , Proteínas Plasmáticas de Unión al Retinol/análisis , Síndrome Coronario Agudo/diagnóstico , Síndrome Coronario Agudo/epidemiología , Anciano , Biomarcadores/sangre , Estudios de Casos y Controles , China/epidemiología , HDL-Colesterol/sangre , LDL-Colesterol/sangre , Femenino , Factores de Riesgo de Enfermedad Cardiaca , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Prevalencia , Medición de Riesgo , Triglicéridos/sangre , Regulación hacia Arriba
11.
Xenobiotica ; 50(8): 894-905, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31928121

RESUMEN

The current study aimed to investigate the hepatotoxicity of rats administered with chronic low-dose acrylamide (AA) by using metabonomics technology on the basis of ultraperformance liquid chromatography-mass spectrometry (UPLC-MS). A total of 40 male Wistar rats were randomly divided into the following four groups: control, low-dose AA (0.2 mg/kg bw, non-carcinogenic end-point based on the induction of morphological nerve changes in rats), middle-dose AA (1 mg/kg bw), and high-dose AA (5 mg/kg bw). The rats continuously received AA by administering it in drinking water daily for 16 weeks. After the treatment, rat livers were collected for metabonomics analysis and histopathology examination. Principal components analysis (PCA) and partial least-squares discriminant analysis (PLS-DA) were used to investigate the metabonomics profile changes in rat liver tissues and screen the potential biomarkers.Fourteen metabolites were identified with significant changes in intensities (increased or decreased compared with the control group) as a result of treatment (p < 0.05 or p < 0.01). These metabolites included tauro-b-muricholic acid, docosapentaenoic acid, sphingosine 1-phosphate, taurodeoxycholic acid, lysoPE(20:5), cervonyl carnitine, linoleyl carnitine, docosahexaenoic acid, lysoPC(20:4), lysoPE(18:3), PA(20:4), stearidonyl carnitine, alpha-linolenic acid, and lysoPA(18:0).Results showed that chronic exposure to AA at NOAEL (0.2 mg/kg bw) exhibited no toxic effect in rat livers at the metabolic level. AA induced oxidative stress to the liver and disrupted lipid metabolism. The results of liver histopathology examination further supported the metabonomic results.


Asunto(s)
Acrilamida/metabolismo , Acrilamida/administración & dosificación , Acrilamida/toxicidad , Animales , Biomarcadores/metabolismo , Relación Dosis-Respuesta a Droga , Metabolismo de los Lípidos/efectos de los fármacos , Hígado/metabolismo , Masculino , Metaboloma/efectos de los fármacos , Metabolómica , Estrés Oxidativo , Ratas , Ratas Wistar , Pruebas de Toxicidad Crónica
12.
Nanomedicine ; 29: 102252, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32615336

RESUMEN

Targeting cisplatin to the sites of action and decreasing its side effects are still major challenges. Here, we introduced a polyglutamic acid-platinum(IV) prodrug nanoconjugates (γ-PGA-CA-Pt(IV)) constructed by polyglutamic acid and modified platinum(IV) prodrug to reserve the anti-tumor efficacy of cisplatin with decreased side effects. We describe the synthesis, physico-chemical characterization, and redox- and pH-sensitive releasing behavior of the nanoconjugate. In vitro studies revealed that, when incubated with glutathione in advance, the γ-PGA-CA-Pt(IV) nanoconjugate induced significant apoptosis in human breast carcinoma MCF-7 cells. From in vivo antitumor efficacy evaluation, the γ-PGA-CA-Pt(IV) nanoconjugate obviously improved the survival rate of tumor-bearing mice with inhibition of the tumor growth compared with cisplatin. Meanwhile, the nanoconjugates showed remarkable improved safety profile than the free cisplatin.


Asunto(s)
Neoplasias de la Mama/tratamiento farmacológico , Sistemas de Liberación de Medicamentos , Nanoconjugados/química , Profármacos/farmacología , Animales , Neoplasias de la Mama/patología , Cisplatino/química , Cisplatino/farmacología , Femenino , Humanos , Concentración de Iones de Hidrógeno , Células MCF-7 , Ratones , Oxidación-Reducción , Platino (Metal)/química , Platino (Metal)/farmacología , Ácido Poliglutámico/análogos & derivados , Ácido Poliglutámico/química , Ácido Poliglutámico/farmacología , Profármacos/química , Ensayos Antitumor por Modelo de Xenoinjerto
13.
Plant Physiol ; 176(1): 804-818, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-29142022

RESUMEN

The development of functional chloroplasts relies on the fine coordination of expressions of both nuclear and chloroplast genomes. We have been using the Arabidopsis (Arabidopsis thaliana) yellow variegated (var2) leaf variegation mutant as a tool to dissect the regulation of chloroplast development. In this work, we screened for var2 genetic enhancer modifiers termed enhancer of variegation (evr) mutants and report the characterization of the first EVR locus, EVR1 We showed that EVR1 encodes the cytosolic 80S ribosome 40S small subunit protein RPS21B and the loss of EVR1 causes the enhancement of var2 leaf variegation. We further demonstrated that combined S21 activities from EVR1 and its close homolog, EVR1L1, are essential for Arabidopsis, and they act redundantly in regulating leaf development and var2 leaf variegation. Moreover, using additional cytosolic ribosomal protein mutants, we showed that although mutations in cytosolic ribosomal proteins all enhance var2 leaf variegation to varying degrees, the 40S subunit appears to have a more profound role over the 60S subunit in regulating VAR2-mediated chloroplast development. Comprehensive genetic analyses with var2 suppressors that are defective in chloroplast translation established that the enhancement of var2 leaf variegation by cytosolic ribosomal protein mutants is dependent on chloroplast translation. Based on our data, we propose a model that incorporates the suppression and enhancement of var2 leaf variegation, and hypothesize that VAR2/AtFtsH2 may be intimately involved in the balancing of cytosolic and chloroplast translation programs during chloroplast biogenesis.


Asunto(s)
Cloroplastos/metabolismo , Citosol/metabolismo , Hojas de la Planta/fisiología , Biosíntesis de Proteínas , Proteínas de Arabidopsis/metabolismo , Clonación Molecular , Regulación de la Expresión Génica de las Plantas , Prueba de Complementación Genética , Modelos Biológicos , Familia de Multigenes , Mutación/genética , Filogenia , Plantas Modificadas Genéticamente , Proteínas Ribosómicas/metabolismo , Subunidades Ribosómicas/metabolismo
14.
J Basic Microbiol ; 59(9): 890-900, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31318074

RESUMEN

Saccharopine dehydrogenase (EC 1.5.1.7) regulates the last step of fungal lysine biosynthesis. The gene (Fvsdh) encoding saccharopine dehydrogenase was identified and cloned from the whole genome of Flammulina velutipes. The genomic DNA of Fvsdh is 1257 bp, comprising three introns and four exons. The full-length complementary DNA of Fvsdh comprises 1107 bp with a deduced amino acid sequence of 368 residues. A 1,000-bp promoter sequence containing the TATA box, CAAT box, and several putative cis-acting elements was also identified. The results of tissue expression analysis showed that the expression level of the Fvsdh gene was higher in the pileus than in the stipe whether in the elongation or maturation stage. Further research showed that the lysine contents were 3.03 and 2.95 mg/g in maturation-pileus and elongation-pileus, respectively. In contrast, the lysine contents were 2.49 and 2.07 mg/g in elongation-stipe and maturation-stipe, respectively. To study the function of Fvsdh, we overexpressed Fvsdh in F. velutipes and found that Fvsdh gene expression was increased from 1.1- to 3-fold in randomly selected transgenic strains. The lysine contents were also increased from 1.12- to 1.3-fold in these five transformants, except for strain T3, in which the lysine contents were the same as the control. These results indicate that the expression of the Fvsdh gene can affect the lysine content of F. velutipes.


Asunto(s)
Flammulina/genética , Flammulina/metabolismo , Proteínas Fúngicas/genética , Lisina/biosíntesis , Sacaropina Deshidrogenasas/genética , Secuencia de Bases , Vías Biosintéticas/genética , Clonación Molecular , Flammulina/clasificación , Flammulina/crecimiento & desarrollo , Proteínas Fúngicas/metabolismo , Expresión Génica , Regulación Fúngica de la Expresión Génica , Filogenia , Regiones Promotoras Genéticas , Sacaropina Deshidrogenasas/metabolismo
15.
Molecules ; 24(11)2019 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-31174262

RESUMEN

Corn flour was prepared by wet-milling with the treatment of neutral protease and the gelatinization, thermal and rheological properties were analyzed. Tortilla was prepared with enzyme treated corn flour (ECF) and additives (xanthan gum and cassava starch) and the properties were analyzed. Compared with dry-milling corn flour (DCF) and wet-milling corn flour (WCF), the ECF had less average particle size (16.74 µm), higher peak viscosity and higher final viscosity of 2997 cP and 3300 cP, respectively. The thermal properties showed that ECF had higher ∆H and lower To, Tp and Tc. The G' of ECF gel (6%, w/w) was higher than that of DCF gel and WCF gel. Dynamic viscoelastic measurement indicated that the tortillas made of ECF had lower G' and G″ over the frequency range (0.1-100 rad/s) after adding xanthan gum and cassava starch. The gel structure of tortillas made of ECF was homogeneous in distribution of pores. The gelatinization, thermal and rheological properties of corn flour were improved by addition of neutral protease. The addition of xanthan gum and cassava starch helped to make the tortilla with porous structure and good sensory quality.


Asunto(s)
Pan/análisis , Grano Comestible/química , Harina , Zea mays/química , Manipulación de Alimentos , Tamaño de la Partícula , Almidón , Temperatura , Viscosidad
16.
Soft Matter ; 12(16): 3703-9, 2016 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-26996652

RESUMEN

The combination of a simple modification of the sample addition method to generate a sort of continuously accumulated external stimulation with only minute increments in amplitude and the introduction of probe molecules (herein aniline) within the micelle allow the direct continuous in situ spectroscopic monitoring of possible micellar transitions. In this way, a sphere-to-ellipsoid and further an ellipsoid-to-bilayer micellar transition of sodium dodecyl sulfate (SDS) induced by camphor sulfuric acid (CSA) is observed to experience four stages in the time sequence: (i) the accumulated protons released from CSA in the hydration layer of the micelle stimulate the rearrangement of SDS micelles; (ii) the micelles transform into ellipsoidal shapes as evidenced by the characteristic chemical shift anisotropy and the corresponding molecular dynamic properties from probe molecules; (iii) further protonation of aniline induces the micelle to turn into lamellar structures; (iv) aniline is freed from the micelle while leaving the SDS bilayers undistorted. Moreover, polyaniline nanosheets incorporating SDS bilayers in sandwich structures, which can display excellent capacitive behavior at relatively high current densities for the fabricated supercapacitors, are prepared from the aniline oriented by the bending energy of the SDS bilayers.

18.
Langmuir ; 30(8): 1957-68, 2014 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-24528103

RESUMEN

Effects of cationic ammonium gemini surfactant hexamethylene-1,6-bis(dodecyldimethylammonium bromide) (12-6-12) on the micellization of two triblock copolymers of poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide), F127 (EO97PO69EO97) and P123 (EO20PO70EO20), have been studied in aqueous solution by differential scanning calorimetry (DSC), dynamic light scattering (DLS), isothermal titration calorimetry (ITC), and NMR techniques. Compared with traditional single-chain ionic surfactants, 12-6-12 has a stronger ability of lowering the CMT of the copolymers, which should be attributed to the stronger aggregation ability and lower critical micelle concentration of 12-6-12. The critical micelle temperature (CMT) of the two copolymers decreases as the 12-6-12 concentration increases and the ability of 12-6-12 in lowering the CMT of F127 is slightly stronger than that of P123. Moreover, a combination of ITC and DLS has shown that 12-6-12 binds to the copolymers at the temperatures from 16 to 40 °C. At the temperatures below the CMT of the copolymers, 12-6-12 micelles bind on single copolymer chains and induce the copolymers to initiate aggregation at very low 12-6-12 concentration. At the temperatures above the CMT of the copolymers, the interaction of 12-6-12 with both monomeric and micellar copolymers leads to the formation of the mixed copolymer/12-6-12 micelles, then the mixed micelles break into smaller mixed micelles, and finally free 12-6-12 micelles form with the increase of the 12-6-12 concentration.

19.
Langmuir ; 30(27): 7968-76, 2014 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-24933418

RESUMEN

Cationic quaternary ammonium gemini surfactants C(n)H(2n+1)(CH3)2N(+)CH2CHCHCH2(CH3)2N(+)C(n)H(2n+1)2Br(-) (C(n)C4C(n), n = 12, 8, 6) with alkyl spacers, C(n)H(2n+1)(CH3)2N(+)CH2CHOHCHOHCH2(CH3)2N(+)C(n)H(2n+1)2Br(-) (C(n)C4(OH)2C(n), n = 12, 8, 6, 4) with two hydroxyl groups in alkyl spacers, and cationic ammonium single-chain surfactants C(n)H(2n+1)(CH3)2N(+)Br(-) (C(n)TAB, n = 12, 8, 6) have been chosen to fabricate oppositely charged surfactant mixtures with anionic sulfonate gemini surfactant C12H25N(CH2CH2CH2SO3(-))CH2CH2CH2(CH3)2N(CH2CH2CH2SO3(-))C12H252Na (C12C3C12(SO3)2). Surface tension, electrical conductivity, and isothermal titration microcalorimetry (ITC) were used to study their surface properties, aggregation behaviors, and intermolecular interactions. The mixtures of C12C3C12(SO3)2/C(n)C4(OH)2C(n) (n = 12, 8) and C12C3C12(SO3)2/C12C4C12 show anomalous larger critical micelle concentration (CMC) than C12C3C12(SO3)2, while the mixtures of C12C3C12(SO3)2/C(n)C4(OH)2C(n) (n = 6, 4), C12C3C12(SO3)2/C(n)C4(OH)2C(n) (n = 6, 4), and C12C3C12(SO3)2/C(n)TAB (n = 12, 8, 6) exhibit much lower CMC than C12C3C12(SO3)2. The results indicate that strong hydrophobic interactions between the alkyl chains assisted by strong electrostatic attractions between the headgroups and hydrogen bonds between the spacers lead to the formation of less surface active premicellar aggregates in bulk solution, resulting in the increase of CMC. If these interactions are weakened or inhibited, less surface active premicellar aggregates are no longer formed in the mixtures, and thus the CMC values are reduced. The work reveals that the combination of two surfactants with great self-assembling ability separately may have strong intermolecular binding interactions; however, their mixtures do not always generate superior synergism properties. Only moderate intermolecular interaction can generate the strongest synergism in CMC reduction.

20.
Am J Hematol ; 89(3): 320-4, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24166850

RESUMEN

Sitosterolemia (phytosterolemia) is a rare inherited sterol storage disorder, characterized by significantly elevated plasma levels of plant sterols. The clinical features of sitosterolemia are xanthomas, premature atherosclerosis, arthritis, and, occasionally, liver function impair and hematologic abnormalities. This disorder is caused by mutations of ABCG5/ABCG8 genes. We report here the clinical, laboratory, and molecular genetic features of 13 patients with sitosterolemia from eight unrelated families who had specific hematologic problems of macrothrombocytopenia, hemolytic anemia, and splenomegaly besides the major clinical manifestations. The peripheral blood films showed some unique features: large platelets surrounded by a circle of vacuoles, and various abnormal erythrocyte shapes, especially stomatocyte. According to these distinct changes of blood cell morphology, we identified two sitosterolemia patients who lacked the classical clinical phenomena. All the patients had been misdiagnosed with immune thrombocytopenia (ITP), Evans syndrome, or secondary ITP with delay being 28.8 years between symptom onset and correct diagnosis. These results indicate that sitosterolemia is certainly not as rare as originally thought. The phenomena of macrothrombocytopenia/hemolysis might represent a new platelet disorder. Plasma plant sterols and ABCG5/ABCG8 genes should be analyzed when such hematologic abnormalities are unexplained.


Asunto(s)
Anemia Hemolítica Congénita/genética , Plaquetas/ultraestructura , Errores Diagnósticos , Eritrocitos Anormales/ultraestructura , Hipercolesterolemia/sangre , Enfermedades Intestinales/sangre , Errores Innatos del Metabolismo Lipídico/sangre , Fitosteroles/efectos adversos , Trombocitopenia/genética , Transportador de Casetes de Unión a ATP, Subfamilia G, Miembro 5 , Transportador de Casete de Unión a ATP, Subfamilia G, Miembro 8 , Transportadoras de Casetes de Unión a ATP/genética , Adulto , Forma de la Célula , Colesterol/sangre , Análisis Mutacional de ADN , Diagnóstico Tardío , Exones/genética , Femenino , Humanos , Hipercolesterolemia/complicaciones , Hipercolesterolemia/diagnóstico , Hipercolesterolemia/genética , Enfermedades Intestinales/complicaciones , Enfermedades Intestinales/diagnóstico , Enfermedades Intestinales/genética , Errores Innatos del Metabolismo Lipídico/complicaciones , Errores Innatos del Metabolismo Lipídico/diagnóstico , Errores Innatos del Metabolismo Lipídico/genética , Lipoproteínas/genética , Masculino , Persona de Mediana Edad , Fragilidad Osmótica , Linaje , Fenotipo , Fitosteroles/sangre , Fitosteroles/genética , Fitosteroles/farmacocinética , Prevalencia , Púrpura Trombocitopénica Idiopática/diagnóstico , Esplenectomía , Esplenomegalia/etiología , Esplenomegalia/cirugía , Vacuolas/ultraestructura , Xantomatosis/etiología
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