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1.
Cell Commun Signal ; 21(1): 156, 2023 06 27.
Artículo en Inglés | MEDLINE | ID: mdl-37370099

RESUMEN

BACKGROUND: Golgi apparatus (GA) is assembled as a crescent-like ribbon in mammalian cells under immunofluorescence microscope without knowing the shaping mechanisms. It is estimated that roughly 1/5 of the genes encoding kinases or phosphatases in human genome participate in the assembly of Golgi ribbon, reflecting protein modifications play major roles in building Golgi ribbon. METHODS: To explore how Golgi ribbon is shaped as a crescent-like structure under the guidance of protein modifications, we identified a protein complex containing the scaffold proteins Ajuba, two known GA regulators including the protein kinase Aurora-A and the protein arginine methyltransferase PRMT5, and the common substrate of Aurora-A and PRMT5, HURP. Mutual modifications and activation of PRMT5 and Aurora-A in the complex leads to methylation and in turn phosphorylation of HURP, thereby producing HURP p725. The HURP p725 localizes to GA vicinity and its distribution pattern looks like GA morphology. Correlation study of the HURP p725 statuses and GA structure, site-directed mutagenesis and knockdown-rescue experiments were employed to identify the modified HURP as a key regulator assembling GA as a crescent ribbon. RESULTS: The cells containing no or extended distribution of HURP p725 have dispersed GA membranes or longer GA. Knockdown of HURP fragmentized GA and HURP wild type could, while its phosphorylation deficiency mutant 725A could not, restore crescent Golgi ribbon in HURP depleted cells, collectively indicating a crescent GA-constructing activity of HURP p725. HURP p725 is transported, by GA membrane-associated ARF1, Dynein and its cargo adaptor Golgin-160, to cell center where HURP p725 forms crescent fibers, binds and stabilizes Golgi assembly factors (GAFs) including TRIP11, GRASP65 and GM130, thereby dictating the formation of crescent Golgi ribbon at nuclear periphery. CONCLUSIONS: The Ajuba/PRMT5/Aurora-A complex integrates the signals of protein methylation and phosphorylation to HURP, and the HURP p725 organizes GA by stabilizing and recruiting GAFs to its crescent-like structure, therefore shaping GA as a crescent ribbon. Therefore, the HURP p725 fiber serves a template to construct GA according to its shape. Video Abstract.


Asunto(s)
Núcleo Celular , Aparato de Golgi , Animales , Humanos , Aparato de Golgi/metabolismo , Fosforilación , Núcleo Celular/metabolismo , Proteína-Arginina N-Metiltransferasas/metabolismo , Mamíferos/metabolismo
2.
Sensors (Basel) ; 22(16)2022 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-36015885

RESUMEN

Soil organic carbon (SOC) plays an important role in the global carbon cycle and soil fertility supply. Rapid and accurate estimation of SOC content could provide critical information for crop production, soil management and soil carbon pool regulation. Many researchers have confirmed the feasibility and great potential of visible and near-infrared (Vis-NIR) spectroscopy in evaluating SOC content rapidly and accurately. Here, to evaluate the feasibility of different spectral bands variable selection methods for SOC prediction, we collected a total of 330 surface soil samples from the cotton field in the Alar Reclamation area in the southern part of Xinjiang, which is located in the arid region of northwest China. Then, we estimated the SOC content using laboratory Vis-NIR spectral. The Particle Swarm optimization (PSO), Competitive adaptive reweighted sampling (CARS) and Ant colony optimization (ACO) were adopted to select SOC feature bands. The partial least squares regression (PLSR), random forest (RF) and convolutional neural network (CNN) inversion models were constructed by using full-bands (400-2400 nm) spectra (R) and feature bands, respectively. And we also analyzed the effects of spectral feature band selection methods and modeling methods on the prediction accuracy of SOC. The results indicated that: (1) There are significant differences in the feature bands selected using different methods. The feature bands selected methods substantially reduced the spectral variable dimensionality and model complexity. The models built by the feature bands selected by CARS, PSO and ACO methods showed the different potential of improvement in model accuracy compared with the full-band models. (2) The CNN model had the best performance for predicting SOC. The R2 of the optimal CNN model is 0.90 in the validation, which was improved by 0.05 and 0.04 in comparison with the PLSR and RF model, respectively. (3) The highest prediction accuracy was archived by the CNN model using the feature bands selected by CARS (validation set R2 = 0.90, RMSE = 0.97 g kg-1, RPD = 3.18, RPIQ = 3.11). This study indicated that using the CARS method to select spectral feature bands, combined with the CNN modeling method can well predict SOC content with higher accuracy.


Asunto(s)
Carbono , Suelo , Carbono/análisis , China , Análisis de los Mínimos Cuadrados , Suelo/química , Espectroscopía Infrarroja Corta/métodos
3.
Int J Mol Sci ; 23(13)2022 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-35806471

RESUMEN

Although histone lysine methylation has been studied in thale cress (Arabidopsis thaliana (L.) Heynh.) and rice (Oryza sativa L.) in recent years, its function in maize (Zea mays L.) remains poorly characterized. To better understand the function of histone lysine methylation in maize, SDG102, a H3 lysine 36 (H3K36) methylase, was chosen for functional characterization using overexpressed and knockout transgenic plants. SDG102-deficiency in maize caused multiple phenotypes including yellow leaves in seedlings, late-flowering, and increased adult plant height, while the overexpression of SDG102 led to reduced adult plant height. The key flowering genes, ZCN8/ZCN7 and MADS4/MADA67, were downregulated in SDG102-deficient plants. Chromatin immunoprecipitation (ChIP) experiments showed that H3 lysine 36 trimethylation (H3K36me3) levels were reduced at these loci. Perturbation of SDG102 expression caused the misexpression of multiple genes. Interestingly, the overexpression or knockout of SDG102 also led to genome-wide decreases and increases in the H3K36me3 levels, respectively. Together, our results suggest that SDG102 is a methyltransferase that catalyzes the trimethylation of H3K36 of many genes across the maize genome, which are involved in multiple biological processes including those controlling flowering time.


Asunto(s)
Arabidopsis , Fenómenos Biológicos , Oryza , Arabidopsis/genética , Regulación de la Expresión Génica de las Plantas , Crecimiento y Desarrollo , N-Metiltransferasa de Histona-Lisina/genética , N-Metiltransferasa de Histona-Lisina/metabolismo , Histonas/genética , Histonas/metabolismo , Lisina/metabolismo , Oryza/genética , Zea mays/genética , Zea mays/metabolismo
4.
Am J Physiol Cell Physiol ; 317(3): C600-C612, 2019 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-31314582

RESUMEN

Mitosis is a complicated process by which eukaryotic cells segregate duplicated genomes into two daughter cells. To achieve the goal, numerous regulators have been revealed to control mitosis. The oncogenic Aurora-A is a versatile kinase responsible for the regulation of mitosis including chromosome condensation, spindle assembly, and centrosome maturation through phosphorylating a range of substrates. However, overexpression of Aurora-A bypasses cytokinesis, thereby generating multiple nuclei by unknown the mechanisms. To explore the underlying mechanisms, we found that SLAN, a potential tumor suppressor, served as a substrate of Aurora-A and knockdown of SLAN induced immature cytokinesis. Aurora-A phosphorylates SLAN at T573 under the help of the scaffold protein 14-3-3η. The SLAN phosphorylation-mimicking mutants T573D or T573E, in contrast to the phosphorylation-deficiency mutant T573A, induced higher level of multinucleated cells, and the endogenous SLAN p573 resided at spindle midzone and midbody with the help of the microtubule motor MKLP1. The Aurora-A- or SLAN-induced multiple nuclei was prevented by the knockdown of 14-3-3η or Aurora-A respectively, thereby revealing a 14-3-3η/Aurora-A/SLAN cascade negatively controlling cytokinesis. Intriguingly, SLAN T573D or T573E inactivated and T573A activated the key cytokinesis regulator RhoA. RhoA interacted with SLAN np573, i.e., the nonphosphorylated form of SLAN at T573, which localized to the spindle midzone dictated by RhoA and ECT2. Therefore, we report here that SLAN mediates the Aurora-A-triggered cytokinesis bypass and SLAN plays dual roles in that process depending on its phosphorylation status.


Asunto(s)
Aurora Quinasa A/biosíntesis , Citocinesis/fisiología , Regulación Enzimológica de la Expresión Génica , Proteínas Supresoras de Tumor/metabolismo , Aurora Quinasa A/genética , Células HEK293 , Humanos , Fosforilación/fisiología
5.
Zhonghua Nan Ke Xue ; 24(4): 297-303, 2018 Apr.
Artículo en Zh | MEDLINE | ID: mdl-30168947

RESUMEN

OBJECTIVE: To study the protective effect of lipoic acid (LA) on the spermatogenic function of the male rats with oligoasthenozoospermia induced by ornidazole (ORN). METHODS: Seventy male SD rats were equally randomized into groups A (solvent control: 1 ml 0.5% CMC-Na + 1 ml olive oil), B (low-dose ORN model: 400 mg/kg ORN suspension + 1 ml olive oil), C (low-dose ORN + low-dose LA treatment: 400 mg/kg ORN + 50 mg/kg LA), D (low-dose ORN + high-dose LA treatment: 400 mg/kg ORN + 100 mg/kg LA), E (high-dose ORN model: 800 mg/kg ORN suspension + 1 ml olive oil), F (high-dose ORN + low-dose LA treatment: 800 mg/kg ORN + 50 mg/kg LA), and G (high-dose ORN + high-dose LA treatment: 800 mg/kg ORN + 100 mg/kg LA), and treated respectively for 20 successive days. Then all the rats were sacrificed and the weights of the body, testis, epididymis and seminal vesicle obtained, followed by calculation of the organ index, determination of epididymal sperm concentration and motility, and observation of the histomorphological changes in the testis and epididymis by HE staining. RESULTS: Compared with group A, group E showed significantly decreased body weight (ï¼»117.67 ± 11.53ï¼½ vs ï¼»88.11 ± 12.65ï¼½ g, P < 0.01) and indexes of the testis (ï¼»1.06 ± 0.12ï¼½ vs ï¼»0.65 ± 0.13ï¼½ %, P < 0.01) and epididymis (ï¼»0.21 ± 0.03ï¼½ vs ï¼»0.17 ± 0.01ï¼½ %, P < 0.01). In comparison with group E, group F exhibited remarkable increases in the epididymal index (ï¼»0.17 ± 0.01ï¼½ vs ï¼»0.20 ± 0.02ï¼½ %, P < 0.01), and so did group G in the body weight (ï¼»88.11 ± 12.65ï¼½ vs ï¼»102.70 ± 16.10ï¼½ g, P < 0.05) and the indexes of the testis (ï¼»0.65 ± 0.13ï¼½ vs ï¼»0.95 ± 0.06ï¼½ %, P < 0.01) and epididymis (ï¼»0.17 ± 0.01ï¼½ vs ï¼»0.19 ± 0.02ï¼½ %, P < 0.05), but no obvious difference was observed in the index of seminal vesicle among different groups. Compared with group A, group B manifested significant decreases in sperm motility (ï¼»74.12 ± 8.73ï¼½ vs ï¼»40.25 ± 6.08ï¼½ %, P < 0.01), and so did group E in sperm count (ï¼»38.59 ± 6.40ï¼½ vs ï¼»18.67 ± 4.59ï¼½ ×105/100 mg, P < 0.01) and sperm motility (ï¼»74.12 ± 8.73ï¼½ vs ï¼»27.58 ± 8.43ï¼½ %, P < 0.01). Sperm motility was significantly lower in group B than in C and D (ï¼»40.25 ± 6.08ï¼½ vs ï¼»58.13 ± 7.62ï¼½ and ï¼»76.04 ± 8.44ï¼½%, P < 0.01), and so were sperm count and motility in group E than in F and G (ï¼»18.67 ± 4.59ï¼½ vs ï¼»25.63 ± 9.66ï¼½ and ï¼»29.92 ± 4.15ï¼½ ×105/100 mg, P < 0.05 and P < 0.01; ï¼»27.58 ± 8.43ï¼½ vs ï¼»36.56 ± 11.08ï¼½ and ï¼»45.05 ± 9.59ï¼½ %, P < 0.05 and P < 0.01). There were no obvious changes in the histomorphology of the testis and epididymis in groups A, B, C and D. Compared with group A, group E showed necrotic and exfoliated spermatogenic cells with unclear layers and disorderly arrangement in the seminiferous tubules and remarkably reduced sperm count with lots of noncellular components in the epididymal cavity, while groups F and G exhibited increased sperm count in the seminiferous tubules and epididymis lumen, also with exfoliation, unclear layers and disorderly arrangement of spermatogenic cells, but significantly better than in group E. CONCLUSIONS: LA can reduce ORN-induced damage to the spermatogenetic function of rats, improve sperm quality, and protect the reproductive system.


Asunto(s)
Antioxidantes/farmacología , Astenozoospermia/tratamiento farmacológico , Oligospermia/tratamiento farmacológico , Espermatogénesis/efectos de los fármacos , Ácido Tióctico/farmacología , Animales , Astenozoospermia/inducido químicamente , Peso Corporal/efectos de los fármacos , Epidídimo/anatomía & histología , Epidídimo/efectos de los fármacos , Masculino , Oligospermia/inducido químicamente , Ornidazol , Distribución Aleatoria , Ratas , Ratas Sprague-Dawley , Vesículas Seminales/anatomía & histología , Vesículas Seminales/efectos de los fármacos , Túbulos Seminíferos/anatomía & histología , Túbulos Seminíferos/efectos de los fármacos , Recuento de Espermatozoides , Motilidad Espermática/efectos de los fármacos , Espermatozoides/efectos de los fármacos , Testículo/anatomía & histología , Testículo/efectos de los fármacos
6.
Zhonghua Nan Ke Xue ; 24(4): 317-321, 2018 Apr.
Artículo en Zh | MEDLINE | ID: mdl-30168950

RESUMEN

OBJECTIVE: To explore Mycoplasma genitalium (MG) infection in the urogenital tract of infertile men and its influence on semen quality. METHODS: Semen samples were collected from 352 infertile males in the Center of Reproductive Medicine of Nanjing General Hospital from March to July 2015. MG infection was detected by real-time fluorescence simultaneous amplification and testing and semen analyses were conducted according to the WHO Laboratory Manual for the Examination and Processing of Human Semen (5th Ed) on the semen pH value, semen volume, total sperm count, sperm concentration, total sperm motility, percentages of progressively motile sperm (PMS) and immotile sperm (IMS), and sperm DNA fragmentation index (DFI). The data obtained were subjected to statistical analysis by t-test and non-parametric test (Wilcoxon test). RESULTS: MG infection was found in 3.4% (12/352) of the infertile patients. Compared with the MG-positive cases, the MG-negative ones showed a significantly higher semen volume (ï¼»2.85 ± 0.14ï¼½ vs ï¼»3.84 ± 0.12ï¼½ ml, P = 0.008) and percentage of PMS (ï¼»15.86±1.72ï¼½ vs ï¼»60.95 ± 5.63ï¼½ %, P = 0.032) but a lower DFI (ï¼»30.73 ±2.24ï¼½ vs ï¼»20.71 ± 1.55ï¼½%, P = 0.014). However, no statistically significant differences were observed between the two groups in the semen pH value (7.38 ±0.02 vs 7.39 ± 0.01, P = 0.774), sperm concentration (ï¼»52.96 ± 15.78ï¼½ vs ï¼»60.05 ± 4.29ï¼½×106/ml, P = 0.683), sperm count (ï¼»154.15 ± 46.37ï¼½ vs ï¼»221.56 ± 15.43ï¼½×106, P = 0.236), total sperm motility (ï¼»29.04 ± 3.11ï¼½ vs ï¼»33.52 ± 1.51ï¼½ %, P = 0.626), or percentage of IMS (ï¼»23.57 ± 0.99ï¼½ vs ï¼»62.34 ± 1.69ï¼½ %, P = 0.691). CONCLUSIONS: Urogenital MG infection is common in infertile males and potentially affects the semen quality, especially sperm vitality of the patient.


Asunto(s)
Infertilidad Masculina/microbiología , Enfermedades Urogenitales Masculinas/microbiología , Infecciones por Mycoplasma/complicaciones , Mycoplasma genitalium , Análisis de Semen , Fragmentación del ADN , Humanos , Infertilidad Masculina/fisiopatología , Masculino , Semen , Recuento de Espermatozoides , Motilidad Espermática , Espermatozoides/fisiología
7.
Zhonghua Nan Ke Xue ; 22(12): 1122-1130, 2016 Dec.
Artículo en Zh | MEDLINE | ID: mdl-29282919

RESUMEN

OBJECTIVE: To assess the effects of testicular sperm and epididymal sperm on the outcomes of ICSI for patients with obstructive azoospermia. METHODS: We searched PubMed, MEDLINE, EMBASE, Cochrane, CNKI, VIP, CBM, and Wanfang Database up to December 2015 for published literature relevant to ICSI with testicular or epididymal sperm for obstructive azoospermia patients. According to the inclusion and exclusion criteria, two reviewers independently conducted literature screening, data extraction and quality assessment of the included trials, followed by meta-analysis with the RevMan 5.3 software. RESULTS: A total of 14 studies were identified, involving 1 278 patients and 1 553 ICSI cycles. ICSI with epididymal sperm exhibited a significantly higher fertilization rate than that with testicular sperm (RR = 1.08, 95% CI 1.05-1.11, P<0.01). No statistically significant differences were observed between the epididymal and testicular sperm groups in the rates of cleavage (RR = 1.04, 95% CI 0.99-1.10, P = 0.13), good-quality embryo (RR = 1.01, 95% CI 0.93-1.09,P = 0.85), implantation (RR = 1.14, 95% CI 0.75-1.73, P = 0.55), clinical pregnancy (RR = 1.14, 95% CI 0.98-1.31, P = 0.08), and miscarriage (RR = 0.86, 95% CI 0.53-1.39,P = 0.54). CONCLUSIONS: ICSI with epididymal sperm yields a markedly higher fertilization rate than that with testicular sperm, but has no statistically significant differences from the latter in the rates of cleavage, good-quality embryo, implantation, clinical pregnancy, and miscarriage in the treatment of obstructive azoospermia.


Asunto(s)
Azoospermia/terapia , Epidídimo/citología , Inyecciones de Esperma Intracitoplasmáticas , Espermatozoides/citología , Testículo/citología , Aborto Espontáneo , Implantación del Embrión , Femenino , Humanos , Masculino , Oligospermia , Embarazo , Índice de Embarazo
8.
Zhonghua Nan Ke Xue ; 22(1): 52-6, 2016 Jan.
Artículo en Zh | MEDLINE | ID: mdl-26931027

RESUMEN

OBJECTIVE: To evaluate the therapeutic effect of Longjintonglin Capsules on type IIIA prostatitis accompanied by abnormal semen liquefaction. METHODS: We selected 140 patients with type IIIA prostatitis accompanied by abnormal semen liquefaction according to the diagnostic standards of the American Institutes of Health (NIH) and treated them with Longjintonglin Capsules orally 3 capsules once tid for 12 weeks. We obtained the NIH Chronic Prostatitis Symptom Indexes (NIH-CPSI), traditional Chinese medicine (TCM) syndrome scores, leukocyte count in the expressed prostatic secretion (EPS), semen liquefaction time, and the results of semen analysis and compared these indicators before and after the treatment. RESULTS: Of the 140 cases, 132 were included in this study, excluding 8 due to their incomplete case histories. Before and after 4, 8 and 12 weeks of medication, the total NIH-CPSI scores were 24.52 ± 5.43, 21.28 ± 4.85, 18.01 ± 4.28, and 14.49 ± 3.65 (P < 0.01), the TCM syndrome scores were 35.63 ± 6.07, 26.66 ± 5.03, 17.37 ± 4.18, and 11.11 ± 3.96 (P < 0.01), and the leukocyte counts (/HP) were 27.50 ± 7.01, 22.38 ± 5.22, 16:76 ± 4.10, and 11.40 ± 4.74 (P < 0.01), respectively. After 12 weeks of treatment, 31 of the patients with type IIIA prostatitis were cured and another 72 well responded, with an overall response rate of 78.0%. Of those with abnormal semen liquefaction, 61 were cured, 39 well responded, and 32 failed to respond, with an overall effectiveness rate of 75.8%. Semen analysis showed significantly increased percentage of progressively motile sperm after 4, 8 and 12 weeks of medication as compared with the baseline (P < 0.01). No abnormal liver or renal function or other adverse reactions were observed during the treatment. CONCLUSION: Longjintonglin Capsules, with its advantages of safety, effectiveness and no obvious adverse effects, deserve to be recommended for the treatment of type IIIA prostatitis accompanied by abnormal semen liquefaction.


Asunto(s)
Medicamentos Herbarios Chinos , Fitoterapia , Prostatitis/tratamiento farmacológico , Cápsulas , Humanos , Masculino , Medicina Tradicional China , Prostatitis/clasificación , Semen , Análisis de Semen
9.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(4): 1235-9, 2016 Apr.
Artículo en Zh | MEDLINE | ID: mdl-30052354

RESUMEN

X-ray tube is the most commonly used equipment in X-ray fluorescence spectrum analysis as excitation source whose primary spectrum has become a major source of the background of X-ray fluorescence spectrum. Background subtraction should go before further analysis of this spectrum. The accuracy of the estimation of the background directly affect the results of subsequent processing steps. In this paper, the tube excitation component of X fluorescence spectrum is analyzed with an estimation method of background intensity against their background characteristics, and structuring theoretical spectral lines based on the measured spectral lines in order to evaluate the effect of spectral processing algorithms. The method utilizes the measured X-ray fluorescence spectrum which does not contain the characteristic peak of the spectrum, In order to estimate the composition of the original spectrum of the X-ray tube. It uses the spectrum that contains the continuous background for interpolating the entire measured spectrum, thereby avoiding overlapping the spectral characteristic peaks or improperly estimating full width at half maximum. This paper compared SNIP, Fourier transform method and the background subtraction method using the measured spectral lines. Using this method to estimate the background is closer to the theoretical background. The results showe that the method for X-ray fluorescence spectrum by X-ray tube excitation is accurate in this article, this method can be used to deduct continuous background, and good applied effectiveness has been achieved in the background subtraction of the actually measured X-ray fluorescence spectrometry.

10.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(4): 1240-4, 2016 Apr.
Artículo en Zh | MEDLINE | ID: mdl-30052355

RESUMEN

This paper proposes the analyzing method of adopting wavelength dispersive X-ray fluorescence spectrometry to measure the content of Cu and Zn in PM2.5. PTFE membrane is used to prepare standard samples and atmospheric particulate samples; a research into sample cup's structure,using polypropylene film of 6.7 µm to help to improved sample cup to package atmospheric particulate samples. The improved sample cup is used to measure the content of Cu and Zn in atmospheric particulate, which can obviously reduce background, improve peak/background ratio and decrease detection limit to target element; discussion is made on the measurement condition of Cu and Zn in PM2.5: taking Kα line as analysis line of Cu and Zn, selecting PX10 as analyzer crystal, using 300 µm pitch collimator, adopting scintillation detector for the Kα of Zn, applying the integrating of flow-gas proportional counter and closed-end proportional counter to the Kα of Cu, setting 50 kV, 50 mA as operating voltage and current. The prepared Cu and Zn standard sample is used to set up working curve, the results show that their linear correlations are better, accuracy are higher, relative standard deviations of Cu and Zn are 2.43% and 2.00%(n=8), detection limit are 0.028 and 0.021 µg·cm-2respectively, and analysis of the single sample only need 60 s. To sum up, this method can quickly and accurately analyze the content of Cu and Zn in PM2.5, and provide scientific basis for study the element content characteristics and source apportionment.

11.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(4): 1127-32, 2016 Apr.
Artículo en Zh | MEDLINE | ID: mdl-30052012

RESUMEN

The contents of radionuclides uranium, thorium and potassium in the sedimentary rocks mainly depend on the contents of clay in the rocks. And the content of clay is the main basis for distinguishing types of sedimentary rock. Therefore, the value of specific activity or content of uranium, thorium and potassium can be as the quantitative index to distinguish sedimentary rock type. The specific activity or content of radionuclides uranium, thorium and potassium with the method of low-background gamma spectrometry can distinguish the type of rock quickly and accurately. Because of the influence of geometry, mass and moisture content in the sample, the accuracy of distinguishing types of rocks is influenced. This paper makes a theoretical discussion and experimental verification on the influence of mass and moisture content on the results of low-background gamma spectrometry. Results show that there is a linear relationship between (cps) of characteristic peak of all radionuclides and the mass of sample while different energy ranges and lithologies have different linear coefficient and trend fitting degree; The moisture content which is no more than 10%(while collecting samples, the moisture content is no more than 10%) has a little influence on the measurement results( the change values are within the twice standard deviation), so the moisture content which has no significant influence on the accuracy of distinguishing types of sedimentary rock using the method of low-background gamma spectrometry could not be considered. The distinguishing experiment of drilling cuttings samples collected from one oil and gas exploration area in Shanxi Dingbian is done. By the mass correction of the measured data, normalized (cps) ((cps) of per unit mass) of uranium, thorium and potassium channel can only roughly divide the types of sedimentary rocks. Therefore, synthetic distinguishing mode is established with (cps) of combination peak of characteristic peak of uranium, thorium and potassium. The type of rocks is further subdivided, and the distinguishing accuracy is more than 75%.

12.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(7): 2043-8, 2015 Jul.
Artículo en Zh | MEDLINE | ID: mdl-26717776

RESUMEN

N, Na, Mg, Al, Si, P, S, Cl, K, Ca, Ti, Cr, Mn, Fe, Ni, Cu, Zn, Br, Rb, Sr, Ba and Pb in herb tea were determined by X-ray fluorescence spectrometry with pressed powder pellets. The measuring conditions of target elements were investigated, including how to select its analytical line. In addition to Ba and Pb using L line, Kalpha line was selected for the rest. When the Compton scattered radiation of Rh Kalpha was measured, The X-ray tube voltage should be appropriately reduced, and the appropriate tube current should be selected. The matrix effect was corrected by empirical coefficient method and using scattered radiation (the Rayleigh scattered radiation of Rh Lalpha, the scattered background of 0.1876 nm wavelength position and the Compton scattered radiation of Rh Kalpha) as internal standard, and the spectral overlapping interference of some elements (N, Na, Ca, Ti, Mn, Sr and Ba) was corrected. For the target elements, the detection limit of this method was low, and its accuracy and precision were high. The results showed that there were abandon of elements in herb tea, of which different kinds had different components, even the same kind of herb tea with different source had some difference in element and content more or less, however, there was a lot of similarity between the features of its components. In a word, this method could achieve multi-element determination of herb tea, and it was simple in operation, low cost, rapid, and accurate.


Asunto(s)
Espectrometría de Fluorescencia , Tés de Hierbas/análisis , Oligoelementos/análisis
13.
JACS Au ; 4(7): 2514-2522, 2024 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-39055143

RESUMEN

CO2 electroreduction (CO2RR) to generate valuable chemicals in acidic electrolytes can improve the carbon utilization rate in comparison to that under alkaline conditions. However, the thermodynamically more favorable hydrogen evolution reaction under an acidic electrolyte makes the CO2RR a big challenge. Herein, robust metal phthalocyanine(Pc)-based (M = Ni, Co) conductive metal-covalent organic frameworks (MCOFs) connected by strong metal tetraaza[14]annulene (TAA) linkage, named NiPc-NiTAA and NiPc-CoTAA, are designed and synthesized to apply in the CO2RR in acidic electrolytes for the first time. The optimal NiPc-NiTAA exhibited an excellent Faradaic efficiency (FECO) of 95.1% and a CO partial current density of 143.0 mA cm-2 at -1.5 V versus the reversible hydrogen electrode in an acidic electrolyte, which is 3.1 times that of the corresponding metal-organic framework NiPc-NiN4. The comparison tests and theoretical calculations reveal that in-plane full π-d conjugation MCOF with a good conductivity of 3.01 × 10-4 S m-1 accelerates migration of the electrons. The NiTAA linkage can tune the electron distribution in the d orbit of metal centers, making the d-band center close to the Fermi level and then activating CO2. Thus, the active sites of NiPc and NiTAA collaborate to reduce the *COOH formation energy barrier, favoring CO production in an acid electrolyte. It is a helpful route for designing outstanding conductive MCOF materials to enhance CO2 electrocatalysis under an acidic electrolyte.

14.
J Mater Chem B ; 12(23): 5734-5748, 2024 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-38771222

RESUMEN

Biomaterials with dual functions of osteoimmunomodulation and bone repair are very promising in the field of orthopedic materials. For this purpose, we prepared copper-based carbon dots (CuCDs) and doped them into oxychondroitin sulfate/poly-acrylamide hydrogel (OPAM) to obtain a hybrid hydrogel (CuCDs/OPAM). We evaluated its osteoimmunomodulatory and bone repair properties in vitro and in vivo. The obtained CuCDs/OPAM exhibited good rBMSCs-cytocompatibility and anti-inflammatory properties in vitro. It also could effectively promote rBMSCs differentiation and the expression of osteogenic differentiation factors from rBMSCs under an inflammatory environment. Moreover, CuCDs/OPAM could induce macrophage phenotype switching (from M1-type macrophages to M2-type macrophages) in vivo, which is beneficial for anti-inflammatory action and presents good osteoimmunomodulation capability to induce a bone immune microenvironment to promote the differentiation of rBMSCs. In conclusion, CuCDs/OPAM hydrogel has dual functions of osteoimmunomodulatory and bone repair and is a promising bone filling and repair material.


Asunto(s)
Regeneración Ósea , Carbono , Cobre , Hidrogeles , Osteogénesis , Osteogénesis/efectos de los fármacos , Hidrogeles/química , Hidrogeles/farmacología , Regeneración Ósea/efectos de los fármacos , Carbono/química , Carbono/farmacología , Animales , Cobre/química , Cobre/farmacología , Diferenciación Celular/efectos de los fármacos , Materiales Biocompatibles/química , Materiales Biocompatibles/farmacología , Células Madre Mesenquimatosas/efectos de los fármacos , Células Madre Mesenquimatosas/citología , Puntos Cuánticos/química , Ratones , Células Cultivadas , Macrófagos/efectos de los fármacos , Macrófagos/citología
15.
Transl Cancer Res ; 13(5): 2509-2517, 2024 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-38881925

RESUMEN

Background: The efficacy of immunotherapy for brain metastases from small cell lung cancer (SCLC) is relatively low, and the tumor microenvironment of SCLC brain metastases is still unknown. Therefore, we investigated the distribution of tumor-infiltrating lymphocytes (TILs) and the expression of programmed cell death-ligand 1 (PD-L1) in patients with brain metastases from SCLC to explore the tumor microenvironment of SCLC brain metastases. Methods: A retrospective analysis was performed on 12 surgical specimens of brain metastases from patients with SCLC treated in the Department of Neurosurgery of The First Affiliated Hospital of Anhui Medical University from June 2017 to June 2022. The inclusion criteria for this study were the following: (I) a pathologically confirmed diagnosis of SCLC brain metastases; (II) surgical resection of brain metastases; (III) age >18 years; (IV) and complete clinical data. Patient-related data were retrieved from the inpatient medical record system, telephone follow-up of patients date of death, and overall survival (OS). The immunofluorescence-based tissue microenvironment analysis panel (MAP) was utilized for the detection of TILs, including CD3, CD8, programmed cell death 1 (PD-1), and PD-L1, in formalin-fixed and paraffin-embedded archival specimens of brain metastases. The expression levels of PD-L1 in tumor cells were detected by immunohistochemistry. The correlation between the OS and the above-mentioned markers was analyzed in the 12 patients. Results: Twelve patients were included in the study. The patients' ages ranged from 51-78 years with a median of 68 years, with 1 female and 11 males. Among 12 patients with SCLC brain metastases: positive rates of CD3+ TILs in the tumor parenchyma vs. tumor stroma were 0.60%±0.94% vs. 1.76%±2.72% (P=0.01), respectively; positive rates of CD8+ TILs in the tumor parenchyma vs. tumor stroma were 0.80%±0.78% vs. 2.46%±3.72% (P=0.02), respectively. There was no co-expression of CD8+ and PD-1+ TILs in the tumor parenchyma of 11 cases, and the infiltration density of coexpressed CD3+ and PD-1+ TILs was more than 10/mm2 in only 1 case. There was no coexpression of CD3+ and PD-1+ TIL in the stroma of 10 cases, and the infiltration density of CD8+ and PD-1+ TILs was more than 10/mm2 in 2 cases. Immunohistochemistry was used to detect the expression of PD-L1 in 12 cases of SCLC metastatic lesions, and 3 cases (25%) were positive. Survival analysis showed that patients with positive intraepithelial CD3+ TILs had significantly longer OS [hazard ratio 3.383, 95% confidence interval (CI): 0.959-11.940; P=0.04]. Conclusions: Our study further demonstrated the immune microenvironment of SCLC brain metastases. The distribution of TILs in SCLC brain metastases is low and mainly distributed in the stroma, with the expression of PD-L1 in these tumor tissues being low. Further exploration of the immune microenvironment of SCLC brain metastases is of great significance for potential treatment.

16.
Plants (Basel) ; 13(18)2024 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-39339602

RESUMEN

Phytohormones are vital for developmental processes, from organ initiation to senescence, and are key regulators of growth, development, and photosynthesis. In natural environments, plants often experience high light (HL) intensities coupled with elevated temperatures, which pose significant threats to agricultural production. However, the response of phytohormone-related genes to long-term HL exposure remains unclear. Here, we examined the expression levels of genes involved in the biosynthesis of ten phytohormones, including gibberellins, cytokinins, salicylic acid, jasmonic acid, abscisic acid, brassinosteroids, indole-3-acetic acid, strigolactones, nitric oxide, and ethylene, in two winter wheat cultivars, Xiaoyan 54 (XY54, HL tolerant) and Jing 411 (J411, HL sensitive), when transferred from low light to HL for 2-8 days. Under HL, most genes were markedly inhibited, while a few, such as TaGA2ox, TaAAO3, TaLOG1, and TaPAL2, were induced in both varieties. Interestingly, TaGA2ox2 and TaAAO3 expression positively correlated with sugar content but negatively with chlorophyll content and TaAGP expression. In addition, we observed that both varieties experienced a sharp decline in chlorophyll content and photosynthesis performance after prolonged HL exposure, with J411 showing significantly more sensitivity than XY54. Hierarchical clustering analysis classified the phytohormone genes into the following three groups: Group 1 included six genes highly expressed in J411; Group 2 contained 25 genes drastically suppressed by HL in both varieties; and Group 3 contained three genes highly expressed in XY54. Notably, abscisic acid (ABA), and jasmonic acid (JA) biosynthesis genes and their content were significantly higher, while gibberellins (GA) content was lower in XY54 than J411. Together, these results suggest that the differential expression and content of GA, ABA, and JA play crucial roles in the contrasting responses of tolerant and sensitive wheat cultivars to leaf senescence induced by long-term HL. This study enhances our understanding of the mechanisms underlying HL tolerance in wheat and can guide the development of more resilient wheat varieties.

17.
Guang Pu Xue Yu Guang Pu Fen Xi ; 33(8): 2242-5, 2013 Aug.
Artículo en Zh | MEDLINE | ID: mdl-24159885

RESUMEN

The present paper discusses the influence of matrix effect on measurement results when portable energy dispersive X-ray fluorescence analyzer is used for the determination of Ni in soil. Based on the scattered X-ray intensity of WL(alpha) emitted from the X-ray tube on the sample, a correction method was proposed, and it combines with the correction of absorption element, which can effectively overcome the matrix effect. The correlation coefficient of the content prediction model based on this method is 0.999 and the residual standard deviation is 2.541. The average relative error is 3.90 when the content prediction model is used to measure the content of Ni in the national standard soil samples, so the results coincide well with standard values, and the precision is high.

18.
Int J Biol Macromol ; 241: 124522, 2023 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-37100332

RESUMEN

Acellular porcine aorta (APA) is an excellent candidate for an implanted scaffold but needs to be modified with appropriate cross-linking agent to increase its mechanical property and storage time in vitro as well as to give itself some bioactivities and eliminate its antigenicity for acting as a novel esophageal prosthesis. In this paper, a polysaccharide crosslinker (oxidized chitosan, OCS) was prepared by oxidizing chitosan using NaIO4 and further used to fix APA to prepare a novel esophageal prosthesis (scaffold). And then the surface modification with dopamine (DOPA) and strontium-doped calcium polyphosphate (SCPP) were performed one after another to prepare DOPA/OCS-APA and SCPP-DOPA/OCS-APA to improve the biocompatibility and inhibit inflammation of the scaffolds. The results showed that the OCS with a feeding ratio of 1.5:1.0 and a reaction time of 24 h had a suitable molecular weight and oxidation degree, almost no cytotoxicity and good cross-linking effect. Compared with glutaraldehyde (GA) and genipin (GP), OCS-fixed APA could provide a more suitable microenvironment for cell proliferation. The vital cross-linking characteristics and cytocompatibility of SCPP-DOPA/OCS-APA were evaluated. Results suggested that SCPP-DOPA/OCS-APA exhibited suitable mechanical properties, excellent resistance to enzymatic degradation/acid degradation, suitable hydrophilicity, and the ability to promote the proliferation of Human normal esophageal epithelial cells (HEECs) and inhibit inflammation in vitro. In vivo tests also confirmed that SCPP-DOPA/OCS-APA could diminish the immunological response to samples and had a positive impact on bioactivity and anti-inflammatory. In conclusion, SCPP-DOPA/OCS-APA could act as an effective, bioactive artificial esophageal scaffold and be expected to be used for clinical in the future.


Asunto(s)
Quitosano , Dopamina , Porcinos , Animales , Humanos , Dihidroxifenilalanina , Antiinflamatorios/farmacología , Inflamación/tratamiento farmacológico , Andamios del Tejido , Ingeniería de Tejidos/métodos , Reactivos de Enlaces Cruzados
19.
ACS Biomater Sci Eng ; 9(5): 2452-2469, 2023 05 08.
Artículo en Inglés | MEDLINE | ID: mdl-37000687

RESUMEN

Modulating both inflammation and stem cells by designing an artificial joint material to obtain the continuous prevention and control on aseptic loosening (AL) is a novel strategy. In this paper, graphene/europium-doped calcium polyphosphate (GNPs/ECPP) particles were obtained by ultrasound method and spark plasma sintering (SPS) method. The prepared particles were used to modulate the inflammatory response and further obtain cascade regulation on the proliferation, recruitment, and differentiation of stem cells. The results showed that particles obtained by SPS had a stronger effect on promoting the proliferation and differentiation of stem cells, while by ultrasound method more stem cells were recruited. Besides, the graphene and Eu3+ contained in the particles obtained by SPS method could effectively play a synergistic role on the differentiation of stem cells. In vivo experiment results demonstrated that the composite particles effectively suppress the inflammatory response, recruit stem cells, and prevent AL by inhibiting the secretion of inflammatory factors.


Asunto(s)
Grafito , Macrófagos , Células Madre , Diferenciación Celular , Proliferación Celular
20.
Carbohydr Polym ; 310: 120724, 2023 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-36925249

RESUMEN

Currently commercial glutaraldehyde (GA)-crosslinked bioprosthetic valve leaflets (BVLs) suffer from thromboembolic complications, calcification, and limited durability, which are the major stumbling block to wider clinical application of BVLs. Thus, developing new-style BVLs will be an urgent need to enhance the durability of BVLs and alleviate thromboembolic complications. In this study, a quick and effective collaborative strategy of the double crosslinking agents (oxidized polysaccharide and natural active crosslinking agent) was reported to realize enhanced mechanical, and structural stability, excellent hemocompatibility and anti-calcification properties of BVLs. Dialdehyde xanthan gum (AXG) exhibiting excellent stability to heat, acid-base, salt, and enzymatic hydrolysis was first introduced to crosslink decellularized porcine pericardium (D-PP) and then curcumin with good properties of anti-inflammatory, anti-coagulation, anti-liver fibrosis, and anti-atherosclerosis was used to synergistically crosslink and multi-functionalize D-PP to obtain AXG + Cur-PP. A comprehensive evaluation of structural characterization, hemocompatibility, endothelialization potential, mechanical properties and component stability showed that AXG + Cur-PP exhibited better anti-thrombotic properties and endothelialization potential, milder immune responses, excellent anti-calcification properties and enhanced mechanical properties compared with GA-crosslinked PP. Overall, this cooperative crosslinking strategy provides a novel solution to achieve BVLs with enhanced mechanical properties and excellent anti-coagulation, anti-inflammatory, anti-calcification, and the ability to promote endothelial cell proliferation.


Asunto(s)
Bioprótesis , Curcumina , Prótesis Valvulares Cardíacas , Porcinos , Animales , Curcumina/farmacología , Reactivos de Enlaces Cruzados/química , Glutaral/química
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