Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 66
Filtrar
Más filtros

País/Región como asunto
Tipo del documento
País de afiliación
Intervalo de año de publicación
1.
Virol J ; 20(1): 264, 2023 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-37968757

RESUMEN

The porcine pseudorabies virus (PRV) is one of the most devastating pathogens and brings great economic losses to the swine industry worldwide. Viruses are intracellular parasites that have evolved numerous strategies to subvert and utilize different host processes for their life cycle. Among the different systems of the host cell, the cytoskeleton is one of the most important which not only facilitate viral invasion and spread into neighboring cells, but also help viruses to evade the host immune system. RhoA is a key regulator of cytoskeleton system that may participate in virus infection. In this study, we characterized the function of RhoA in the PRV replication by chemical drugs treatment, gene knockdown and gene over-expression strategy. Inhibition of RhoA by specific inhibitor and gene knockdown promoted PRV proliferation. On the contrary, overexpression of RhoA or activation of RhoA by chemical drug inhibited PRV infection. Besides, our data demonstrated that PRV infection induced the disruption of actin stress fiber, which was consistent with previous report. In turn, the actin specific inhibitor cytochalasin D markedly disrupted the normal fibrous structure of intracellular actin cytoskeleton and decreased the PRV replication, suggesting that actin cytoskeleton polymerization contributed to PRV replication in vitro. In summary, our data displayed that RhoA was a host restriction factor that inhibited PRV replication, which may deepen our understanding the pathogenesis of PRV and provide further insight into the prevention of PRV infection and the development of anti-viral drugs.


Asunto(s)
Herpesvirus Suido 1 , Seudorrabia , Porcinos , Animales , Herpesvirus Suido 1/fisiología , Actinas , Línea Celular , Replicación Viral
2.
Inorg Chem ; 62(35): 14216-14227, 2023 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-37615424

RESUMEN

Novel endohedral metallofullerenes (EMFs), namely, Er2C2@C2v(5)-C80, Er2C2@Cs(6)-C82, Er2C2@Cs(15)-C84, Er2C2@C2v(9)-C86, Er2C2@Cs(15)-C86, and Er2C2@Cs(32)-C88, had been experimentally synthesized, and the unique structures and many fascinating properties had also been widely explored. Nevertheless, the position of the Er atoms inside the cage shows a severe disorder within the stable EMF monomer, which is difficult to understand and explain from the experimental point of view. In this work, based on the density functional theoretical calculations, the Er2C2@Cs(6)-C82 has 73 directional isomers and 2 Er atoms that are far beyond from Er-Er single bonding and tend to be close to the cage side (marked as "shell"), and the core (Er2C2 units) takes on a butterfly shape as generally revealed. The energy difference between any two of the isomers is in the range of 0.05 to 25.6 kcal/mol, indicating a relatively easy thermodynamic transition between the isomers. The other five Er carbide cluster EMFs (Er2C2@C2v(5)-C80, Er2C2@Cs(15)-C84, Er2C2@C2v(9)-C86, Er2C2@Cs(15)-C86, and Er2C2@Cs(32)-C88) are also studied in the same way, and 30, 37, 39, and 43 most stable Er-oriented sites inside the cage, respectively, are obtained. In addition, the shape of the Er2C2 gradually changed from butterfly to linear. Moreover, the electronic structure and molecular orbital analyses show that it is easy for Er2C2@C80-88 to form a charge transfer state of [Er2C2]4+@[C80-88]4- via the dynamic core-shell coordination equilibrium. Er2C2 with a steep drop in chemical stability is restricted to forming varying degrees of metastable states in the shell, determined by the shell size, to ensure the overall stability. The lowest unoccupied molecular orbital energy level of these EMFs is increased by 0.5-1.1 eV compared with fullerenes C80-88, potentially providing favorable conditions for suitable energy level matching with EMF as an electron acceptor used in organic solar cell devices.

3.
Phys Chem Chem Phys ; 25(37): 25871-25879, 2023 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-37725156

RESUMEN

Tri-(2,4,6-trichlorophenyl)methyl (TTM) based radicals can be promising in providing relatively high fluorescence quantum efficiency. In this study, we have evaluated the photoluminescence properties of a series of TTM-based radicals by means of DFT and TD-DFT methods. The optimized structures of the ground states (D0) and the first excited states (D1) of all the radicals are calculated and the computed emission bands are comparable with previous experimental results. knr is determined from transition dipole moments (µ12) and the energy gaps between D0 and D1 (ΔE), both of which can be regulated by the conjugated structures from the substituent groups. knr was derived from the mode-averaging method and is consistent with the experimental results. Factors influencing kr and knr, including the potential energy differences (ΔG0), the vibrational reorganization energies (λ) and the electron coupling term (Hab), are discussed. By comparing kr and knr in solvents with different polarities (cyclohexane, toluene, and chloroform), TTM based radicals in cyclohexane exhibit the most promising fluorescence efficiencies. Besides, two substituted radicals, namely 2Br-TTM-3PCz and 2F-TTM-3PCz, have been fabricated. The results show that fluorine atoms are able to increase ΔG0 and a considerably small knr has been predicted. We expect that our calculation can benefit the design of light-emitting molecules in further experiments.

4.
Plant Physiol ; 183(2): 656-670, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32241877

RESUMEN

One of the biggest challenges in clonal propagation of grapevine (Vitis vinifera) is difficulty of rooting. Adventitious root initiation and development are the critical steps in the cutting and layering process of grapevine, but the molecular mechanism of these processes remains unclear. Previous reports have found that microRNA (miRNA)-encoded peptides (miPEPs) can regulate plant root development by increasing the transcription of their corresponding primary miRNA. Here, we report the role of a miPEP in increasing adventitious root formation in grapevine. In this study, we performed a global analysis of miPEPs in grapevine and characterized the function of vvi-miPEP171d1, a functional, small peptide encoded by primary-miR171d. There were three small open reading frames in the 500-bp upstream sequence of pre-miR171d. One of them encoded a small peptide, vvi-miPEP171d1, which could increase the transcription of vvi-MIR171d Exogenous application of vvi-miPEP171d1 to grape tissue culture plantlets promoted adventitious root development by activating the expression of vvi-MIR171d Interestingly, neither exogenous application of the vvi-miPEP171d1 peptide nor overexpression of the vvi-miPEP171d1 coding sequence resulted in phenotypic changes in Arabidopsis (Arabidopsis thaliana). Similarly, application of synthetic ath-miPEP171c, the small peptide encoded by the Arabidopsis ortholog of vvi-MIR171d, inhibited the growth of primary roots and induced the early initiation of lateral and adventitious roots in Arabidopsis, while it had no effect on grape root development. Our findings reveal that miPEP171d1 regulates root development by promoting vvi-MIR171d expression in a species-specific manner, further enriching the theoretical research into miPEPs.


Asunto(s)
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , MicroARNs/metabolismo , Raíces de Plantas/metabolismo , Vitis/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Regulación de la Expresión Génica de las Plantas , MicroARNs/genética , Fenotipo , Raíces de Plantas/genética , Vitis/genética
5.
Reprod Biomed Online ; 42(3): 589-594, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33384268

RESUMEN

RESEARCH QUESTION: What are the risks associated with cryopreserved semen collected during and after the coronavirus disease 2019 (COVID-19) pandemic wave in Wuhan, China? DESIGN: Retrospective cohort study involving young adult men who were qualified sperm donors at the Hunan Province Human Sperm Bank (China) during the pandemic wave (1 January 2020 to 30 January 2020) and after the wave and return to work (7 April 2020 to 30 May 30 2020). One hundred paired semen and blood specimens from 100 donors were included. One-step single-tube nested quantitative real-time polymerase chain reaction (OSN-qRT-PCR) was used to detect SARS-CoV-2. Moreover, to control the unacceptable risk of false-negative results, a second round of screening was performed with pooled RNA from negative semen samples using crystal digital PCR (cd-PCR). RESULTS: For individual blood and semen samples, the target genes, namely the nucleocapsid protein (N) and open reading frame (ORF-1ab) genes, tested negative in all of the 100 paired samples. Further, as per cd-PCR results, there were >20,000 droplets per well in the RNA for each combined sample and no positive droplets were present for either of the aforementioned target genes. A total of 100 paired semen and blood samples from these two groups tested negative for SARS-CoV-2. CONCLUSIONS: Cryopreserved semen at the Hunan Province Human Sperm Bank during and after the COVID-19 pandemic wave was free of SARS-CoV-2 and was judged safe for external use in the future.


Asunto(s)
COVID-19 , Pandemias , China/epidemiología , Humanos , Masculino , Reacción en Cadena en Tiempo Real de la Polimerasa , Estudios Retrospectivos , SARS-CoV-2 , Semen , Bancos de Esperma , Espermatozoides , Adulto Joven
6.
Inorg Chem ; 60(3): 1480-1490, 2021 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-33427451

RESUMEN

Graphene materials with particular properties are proved to be beneficial to photoelectric devices, but there are rare reports on a positive effect by graphene on emissive layer materials of organic light-emitting diodes (OLEDs) previously. On the basis of the latest important experiments, an OLED device with the aid of graphene quantum dots shows the dawn of their application for luminescent materials. The luminescence performance has been improved, but the understanding of the internal excited-state radiation mechanism of the material needs further study. In this work, the Pt(II)-coordinated graphene quantum dot coplanar structures with different shapes are studied theoretically in detail, and the results present the improvement in phosphorescence under the promoted radiative decay and suppressed nonradiative decay. This composite combines the advantages of transition metal complexes and graphene quantum dots and also exhibits excellent properties in the light absorption region and carrier transportation for the OLED. This comprehensive theoretical calculation research can provide a comprehensive basis of the material design in the future.

7.
Angew Chem Int Ed Engl ; 59(44): 19716-19721, 2020 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-32924218

RESUMEN

Herein we report two new TPE-based 3D MOFs, that is, Sr-ETTB and Co-ETTB (TPE=Tetraphenylethylene, H8 ETTB=4',4''',4''''',4'''''''-(ethene-1,1,2,2-tetrayl)tetrakis(([1,1'-biphenyl]-3,5-dicarboxylic acid))). Through tailoring outer shell electron configurations of SrII and CoII cations, the fluorescence intensity of the MOFs is tuned from high emission to complete non-emission. Sr-ETTB with strong blue fluorescence shows reversible fluorescence variations in response to pressure and temperature, which is directly related to the reversible deformation of the crystal structure. In addition, non-emissive Co-ETTB counterpart exhibits a turn-on fluorescent enhancement under the stimulation of analyte histidine. In the process, TPE-cored linkers in the MOFs are released through competitive coordination substitution and subsequently reassembled to perform aggregation-induced luminescence behavior originated from the organic linkers.

8.
Zhonghua Nan Ke Xue ; 25(11): 978-983, 2019 Nov.
Artículo en Zh | MEDLINE | ID: mdl-32233230

RESUMEN

OBJECTIVE: To investigate the expression of the sperm-specific cation channel (CatSper1) in the epididymal sperm of varicocele (VC) rats and the effect of L-carnitine (LC) on the CatSper1 level. METHODS: Seventy male rats were equally randomized into groups A (normal control), B (VC model control), C (VC treated with normal saline), D (VC treated with low-dose LC), E (VC treated with medium-dose LC), F (VC treated with high-dose LC), and G (VC treated by prolonged medication of high-dose LC). The VC model was established by partial ligation of the left renal vein. At 12 weeks after modeling, the model rats in group C were treated intragastrically with normal saline at 1 ml/kg/d, those in groups D, E and F with LC at 0.05, 0.1 and 0.2 g/kg/d respectively, all for 5 consecutive weeks, and those in group G with LC at 0.2 g/kg/d for 7 successive weeks. Then, all the animals were sacrificed and their epididymides harvested for obtainment of the semen parameters by computer-assisted semen analysis (CASA) and determination of the mRNA and protein expressions of CatSper1 in the sperm by RT-PCR and Western blot. RESULTS: Compared with the rats in group A, those in group B showed significantly decreased percentage of grade a+b sperm (P < 0.01), sperm viability (P < 0.01), sperm concentration (P < 0.01) and expressions of CatSper1 mRNA (1.44 ± 0.67 vs 0.71 ± 0.38, P < 0.01) and protein (1.87 ± 0.67 vs 0.84 ± 0.42, P < 0.01). In comparison with the animals in group C, those in the four LC intervention groups exhibited a markedly increased percentage of grade a+b sperm, sperm viability and mRNA and protein expressions of CatSper1, even more remarkably in groups F and G (P < 0.01). No statistically significant difference, however, was observed in sperm concentration between group C and the LC intervention groups (P > 0.05), nor in the mRNA and protein expressions of CatSper1 between groups F and G. CONCLUSIONS: The expression of CatSper1 is decreased in the epididymal sperm of varicocele rats, and L-carnitine can increase the sperm viability, percentage of grade a+b sperm and CatSper1 expression of the rats.


Asunto(s)
Canales de Calcio/metabolismo , Carnitina/uso terapéutico , Espermatozoides/efectos de los fármacos , Varicocele/metabolismo , Animales , Epidídimo/citología , Masculino , Distribución Aleatoria , Ratas , Recuento de Espermatozoides , Espermatozoides/metabolismo , Varicocele/tratamiento farmacológico
9.
Microb Ecol ; 72(3): 647-58, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-27423979

RESUMEN

Arbuscular mycorrhizal (AM) fungi play key roles in plant nutrition and plant productivity. AM fungal responses to either plant identity or fertilization have been investigated. However, the interactive effects of different plant species and fertilizer types on these symbiotic fungi remain poorly understood. We evaluated the effects of the factorial combinations of plant identity (grasses Avena sativa and Elymus nutans and legume Vicia sativa) and fertilization (urea and sheep manure) on AM fungi following 2-year monocultures in a sown pasture field study. AM fungal extraradical hyphal density was significantly higher in E. nutans than that in A. sativa and V. sativa in the unfertilized control and was significantly increased by urea and manure in A. sativa and by manure only in E. nutans, but not by either fertilizers in V. sativa. AM fungal spore density was not significantly affected by plant identity or fertilization. Forty-eight operational taxonomic units (OTUs) of AM fungi were obtained through 454 pyrosequencing of 18S rDNA. The OTU richness and Shannon diversity index of AM fungi were significantly higher in E. nutans than those in V. sativa and/or A. sativa, but not significantly affected by any fertilizer in all of the three plant species. AM fungal community composition was significantly structured directly by plant identity only and indirectly by both urea addition and plant identity through soil total nitrogen content. Our findings highlight that plant identity has stronger influence than fertilization on belowground AM fungal community in this converted pastureland from an alpine meadow.


Asunto(s)
Biodiversidad , Fertilizantes , Hongos/efectos de los fármacos , Micorrizas/efectos de los fármacos , Plantas/efectos de los fármacos , Plantas/microbiología , Microbiología del Suelo , Suelo/química , Animales , Secuencia de Bases , Biomasa , China , ADN de Hongos/aislamiento & purificación , ADN Ribosómico , Ecosistema , Hongos/clasificación , Hongos/genética , Hongos/crecimiento & desarrollo , Pradera , Hifa/crecimiento & desarrollo , Estiércol , Micorrizas/clasificación , Micorrizas/genética , Micorrizas/crecimiento & desarrollo , Nitrógeno/análisis , Filogenia , Raíces de Plantas/microbiología , Poaceae/microbiología , Ovinos , Esporas Fúngicas/efectos de los fármacos , Esporas Fúngicas/crecimiento & desarrollo , Estadística como Asunto , Simbiosis , Urea/farmacología
10.
Artículo en Zh | MEDLINE | ID: mdl-27089776

RESUMEN

Schistosomiasis is a type of zoonotic parasitosis that severely impairs human health. Rapid detection of infection sources is a key to the control of schistosomiasis. With the effective control of schistosomiasis in China, the detection techniques for infection sources have also been developed. The rate and the intensity of infection among humans and livestocks have been significantly decreased in China, as the control program has entered the transmission control stage in most of the endemic areas. Under this situation, the traditional etiological diagnosing techniques and common immunological methods can not afford rapid detection of infection sources of schistosomiasis. Instead, we are calling for detection methods with higher sensitivity, specificity and stability while being less time-consuming, more convenient and less costing. In recent years, many improved or novel detection methods have been applied for the epidemiological surveillance of schistosomiasis, such as the automatic scanning microscopic image acquisition system, PCR-ELISA, immunosensors, loop-mediated isothermal amplification, etc. The development of new monitoring techniques can facilitate rapid detection of schistosome infection sources in endemic areas.


Asunto(s)
Esquistosomiasis , Animales , China , Schistosoma
11.
Artículo en Zh | MEDLINE | ID: mdl-26541047

RESUMEN

Fifteen soil samples were collected from Oncomelania hupensis culture pond in Miluo Schistosomiasis Control and Prevention Base, Hunan Province. Four strains of bacteria were identified to have molluscacidal effects, numbered as B8, B27, B36 and B59. Compared with the fermentation broth groups and bacteria suspension groups, the fermentation supernatant groups of the four strains showed the strongest molluscacidal effect. The fermentation supernatant of B59 strain showed the best molluscacidal effect, with snail mortalit of 73.3% and 96.7% at 48 h and 72 h of treatment, respectively. SDS-PAGE revealed no proteins in fermentation supernatant, fermentation broth and bacteria suspension of B59 strain. Molecular phylogenetic analysis based on ITS sequence showed that the ITS sequence of strain B59 (accession No. KP146144) was 100% homologous to that of the same fragment of Bacillus cereus (accession No. CP001746).


Asunto(s)
Filogenia , Animales , Moluscocidas , Caracoles
12.
Ann Plast Surg ; 73(6): 710-5, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24830660

RESUMEN

The vascularized whole femur transplantation model is one of the commonly used vascularized bone marrow transplant models. It involves technical complexity and morbidities. To optimize this model, we took 2/3 femur as the carrier of bone marrow cells, and developed a vascularized partial femur model. Four experimental groups were carried out, namely, the syngeneic partial femur transplantation, allogeneic partial femur transplantation with or without cyclosporine A, and allogeneic whole femur transplantation with cyclosporine A. The results showed that the partial femur model was technically simpler and shortened the operative and ischemia time compared to the whole femur model. Gross and histologic appearance confirmed the viability of femur, and its bone marrow inside the bone could also maintain normal morphologically at 60-day posttransplant. Besides, donor multilineage chimerism could be continuously detected in immunosuppressed allogeneic partial femur recipients at 1-, 2-, 3-, 4-, and 8-week posttransplant, and it showed no significant differences when compared with whole femur transplantation. Meanwhile, long-term engraftment of donor-origin cells was also confirmed in recipients' bone marrow, lymph nodes, and spleen, but not in thymus. Therefore, the vascularized partial femur can serve as a continuous resource of bone morrow cells and may provide a useful tool for the study of immune tolerance in vascularized composite allotransplantation.


Asunto(s)
Trasplante de Médula Ósea/métodos , Trasplante Óseo/métodos , Fémur/trasplante , Animales , Quimerismo , Supervivencia de Injerto , Ratas , Ratas Endogámicas Lew , Trasplante Homólogo/métodos , Trasplante Isogénico/métodos
13.
Ann Plast Surg ; 72(1): 94-9, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23403542

RESUMEN

BACKGROUND: A lot of methods have been intensively investigated to improve random skin flap survival. Decreasing inflammation and alleviating tissue injury have been reported to be effective in improving survival ratio. Vasonatrin peptide (VNP) is a chimera of atrial natriuretic peptide (ANP) and C-type natriuretic peptide (CNP). The current study demonstrates that VNP possesses the venodilating actions of CNP, the natriuretic actions of ANP, and the unique arterial vasodilating actions not associated with either ANP or CNP. However, its effects on skin flap survival have not been previously reported. METHODS: Sprague-Dawley rats, weighing 220 to 260 g, were randomly divided into 2 groups, namely, the VNP-treated group and the control group. Rectangular random dorsal skin flaps measuring 3 × 9 cm including the panniculus carnosus were elevated, then the flaps were sutured into their original places. In the VNP group, 0.1 mg/kg of VNP was administered intravenously (IV) after surgery and then daily for 3 days. In the control group, 1 mL/kg of saline was administered IV after surgery and then daily for 3 days. To observe the effects of VNP, blood perfusion, histopathological examination, the inflammatory mediators (tumor necrosis factor α, interleukin 1ß, and interferon γ), and biochemical analysis (malondialdehyde, glutathione, and myeloperoxidase) were detected and the flap viability was evaluated 7 days after surgery by measuring necrotic flap area and total flap area. RESULTS: The viability measurements showed the percentage of flap survival was increased in the VNP-treated group (76.53% ± 6.36%) as compared with the control group (61.12% ± 4.92%) (P < 0.05), and the histological and biochemical assays corroborated the data. The blood perfusion of flaps in the VNP-treated group was higher than the control group (P < 0.05). The inflammatory mediators (tumor necrosis factor α, interleukin 1ß, and interferon γ) were significantly lower in the VNP-treated group than the control group (P < 0.05). CONCLUSIONS: This study found that VNP, which could elevate the tissue blood perfusion and mitigate the tissue damage and inflammatory reaction, is associated with a higher percentage of survival random pattern skin flap area.


Asunto(s)
Factor Natriurético Atrial/farmacología , Supervivencia de Injerto/efectos de los fármacos , Natriuréticos/farmacología , Piel/efectos de los fármacos , Colgajos Quirúrgicos/irrigación sanguínea , Vasodilatadores/farmacología , Administración Intravenosa , Animales , Factor Natriurético Atrial/uso terapéutico , Biomarcadores/metabolismo , Esquema de Medicación , Supervivencia de Injerto/fisiología , Inmunohistoquímica , Flujometría por Láser-Doppler , Natriuréticos/uso terapéutico , Necrosis/etiología , Necrosis/metabolismo , Necrosis/patología , Necrosis/prevención & control , Complicaciones Posoperatorias/metabolismo , Complicaciones Posoperatorias/patología , Complicaciones Posoperatorias/prevención & control , Distribución Aleatoria , Ratas , Ratas Sprague-Dawley , Piel/irrigación sanguínea , Piel/metabolismo , Piel/patología , Colgajos Quirúrgicos/patología , Colgajos Quirúrgicos/fisiología , Vasodilatadores/uso terapéutico
14.
Guang Pu Xue Yu Guang Pu Fen Xi ; 34(10): 2685-9, 2014 Oct.
Artículo en Zh | MEDLINE | ID: mdl-25739208

RESUMEN

In the present research, synchronous fluorescence technique was used for qualitative and quantitative detection of re- constituted milk mixed into two kinds of milk samples, raw milk and pasteurized milk, respectively. The total accuracy of sample was used to evaluate the performance of the qualitative discrimination models. The correlation coefficient (r), the root mean square error of correction (RMSEC) and the root mean square error of prediction (RMSEC) were used to evaluate the perform- ance of the quantitative analysis models. The constant wavelength difference (Δλ) between the excitation and emission scanning was determined to be 80 nm from three-dimensional fluorescence spectrum of milk. The total discrimination accuracy was 100% by partial least squares discrimination analysis (PLS-DA) for raw milk, pasteurized milk and reconstituted milk samples. When checking whether the raw milk and pasteurized milk were mixed with reconstituted milk, the total accuracy of calibration samples was 100% and the accuracy of prediction samples was 75% and 81.25%, respectively. The effects of qualitative discrimination models were satisfactory. The PLS regression was used for quantitative analysis of the reconstituted milk content mixed in raw milk and pasteurized milk. The correlation coefficients of actual values versus predicted values were 0.911 2 and 0.911 2, re-spectively. The RMSEC was 0.042 2 and 0.0384, respectively. The RMSEP was 0.054 8 and 0.057 5, respectively. The cor- relation coefficients of quantitative analysis models could reach up to 0.9. The results showed that synchronous fluorescence technology could be applied for rapid detection of reconstituted milk mixed in fresh milk


Asunto(s)
Fluorescencia , Contaminación de Alimentos , Leche/química , Animales , Calibración , Análisis de los Mínimos Cuadrados
15.
Fitoterapia ; 172: 105763, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38040094

RESUMEN

Filamentous fungi belonging to the genus Aspergillus are prodigious producers of alkaloids, particularly prenylated indole alkaloids, that often exhibit structurally diversified skeletons and potent biological activities. In this study, five prenylated indole alkaloids possessing a bicyclo[2.2.2]diazaoctane core ring system, including a novel derivative, namely aspertaichamide A (1), as well as four known compounds, (+)-stephacidin A (2), sclerotiamide (3), (-)-versicolamide B (4), and (+)-versicolamide B (5), were isolated and identified from A. taichungensis 299, an endophytic fungus obtained from the marine red alga Gelidium amansii. The chemical structures of the compounds were elucidated by comprehensive NMR and HRESIMS spectroscopic analyses. In addition to the previously reported prenylated indole alkaloids, aspertaichamide A (1) was characterized as having an unusual ring structure with the fusion of a 3-pyrrolidone dimethylbenzopyran to the bicyclo[2.2.2]diazaoctane moiety, which was rare in these kinds of compounds. The absolute configuration of 1 was determined by TDDFT-ECD calculations. In vitro cytotoxic assays revealed that the novel compound 1 possessed selective cytotoxic activity against five human tumor cell lines (A549, HeLa, HepG2, HCT-116, and AGS), with IC50 values of 1.7-48.5 µM. Most importantly, compound 1 decreased the viability of AGS cells in a concentration-dependent manner with an IC50 value of 1.7 µM. Further studies indicated that 1 may induce AGS cells programmed cell death via the apoptotic pathway.


Asunto(s)
Antineoplásicos , Aspergillus , Algas Comestibles , Rhodophyta , Humanos , Estructura Molecular , Aspergillus/química , Hongos/química , Alcaloides Indólicos , Antineoplásicos/farmacología
16.
Exp Parasitol ; 134(4): 447-54, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23684910

RESUMEN

The pathogenesis of chronic schistosomiasis is caused by irritation of the schistosome eggs trapped in liver that induce delayed hypersensitive reactions from the surrounding tissues, leading to the formation of inflammatory granuloma and subsequent fibrosis. A Schistosoma japonicum (S. japonicum) single-chain fragment variable (SjscFv) which specifically binds to the S. japonicum soluble immature egg antigen (SIEA) can be used as a target to deliver specific cytokine towards the site of hepatic fibrosis. To test this hypothesis, a novel recombinant plasmid, pVAX1/SjscFv-IL18, was constructed by fusing SjscFv to IL-18 gene with a 45bp glycine-rich linker. Furthermore, experiments on mice showed that pVAX1/SjscFv-IL18 could effectively express IL-18 in the liver and in serum. Hepatic contents of IL-2 and IFN-γ (Th1-type) in S. japonicum-infected mice vaccinated with pVAX1/SjscFv-IL18 increased significantly but those of their IL-4 and IL-10 (Th2-type) decreased as compared to the analyzed results of 4 cytokines in the liver cells of control mice vccinated with pVAX1/IL18. Consistent with the levels of Th1 and Th2 cytokines, mice vaccinated with pVAX1/SjscFv-IL18 developed much less hepatic fibrosis 20weeks after infection, which was evaluated by average volumn of granuloma and collagen contents. These data suggested that the linkage of IL-18 to the target-specific SjscFv molecule appears to be a potentially promising trial route of therapy, the hepatic fibrosis in S. japonicum-infected mice may be ameliorated through effective expression of IL18 in liver.


Asunto(s)
Interleucina-18/genética , Cirrosis Hepática/prevención & control , Hígado/metabolismo , Schistosoma japonicum/genética , Esquistosomiasis Japónica/complicaciones , Anticuerpos de Cadena Única/genética , Animales , ADN de Helmintos/administración & dosificación , Femenino , Interleucina-18/inmunología , Interleucina-18/metabolismo , Hígado/inmunología , Hígado/parasitología , Cirrosis Hepática/parasitología , Ratones , Ratones Endogámicos BALB C , Plásmidos , Distribución Aleatoria , Schistosoma japonicum/inmunología , Esquistosomiasis Japónica/inmunología , Anticuerpos de Cadena Única/inmunología , Anticuerpos de Cadena Única/metabolismo
17.
Zhonghua Nan Ke Xue ; 19(4): 346-9, 2013 Apr.
Artículo en Zh | MEDLINE | ID: mdl-23678716

RESUMEN

OBJECTIVE: To study the effect of Shengjingsan on spermatogenic function following testicular torsion/detorsion in rats and its action mechanism. METHODS: Forty SD male rats were equally randomized to groups A (sham operation), B (control), C (low-dose Shengjingsan), D (medium-dose Shengjingsan) and E (high-dose Shengjingsan). The model of testicular torsion was established by 720 degrees clockwise torsion of the left testis for 4 hours. An hour before operation, the rats of group B received daily gavage of normal saline at 1 ml per kg per d, while those in groups C, D and E that of Shengjingsan at 0.01, 0.02 and 0.03 g per kg per d, all for 35 days. Then all the rats were sacrificed for measuring the semen parameters by CASA and detecting the expression of the CatSper1 gene in the sperm by RT-PCR. RESULTS: Compared with group A, Sperm concentration, the percentage of grade a + b sperm, sperm vitality and CatSper1 expression were significantly lower in group B ([15.30 +/- 6.30] %, [44.42 +/- 6.36] %, [21.00 +/- 6.14] x 10(6)/ml and 1.12 +/- 0.50) than in A ([51.30 +/- 6.60]%, [69.01 +/- 7.20]%, [40.53 +/- 7.01] x 10(6)/ml and 2.04 +/- 0.77) (P < 0.01). Compared with group B, the four parameters were increased remarkably in groups D ([51.63 +/- 3.20] %, [72.09 +/- 2.20]%, [55.30 +/- 5.90] x10(6)/ml and 2.11 +/- 0.20) andE ([55.93 +/- 3.17]%, [73.01 +/- 2.11]%, [58.33 + 4.90] x 10(6)/ml and 2.31 +/- 0.17) (P < 0.01), but not significantly in C ([18.02 +/- 0.23]%, [48.04 +/- 7.01]%, [22.87 +/- 2.10] x 10(6)/ml and 1.19 +/- 0.51) (P > 0.05). CONCLUSION: Shengjingsan can improve sperm parameters following testicular torsion/ detorsion in male rats by regulating their spermatogenic function and improving the expression of CatSper1 in the sperm.


Asunto(s)
Medicamentos Herbarios Chinos/farmacología , Torsión del Cordón Espermático/metabolismo , Espermatogénesis/efectos de los fármacos , Espermatozoides/metabolismo , Animales , Canales de Calcio/metabolismo , Masculino , Ratas , Ratas Sprague-Dawley , Recuento de Espermatozoides , Torsión del Cordón Espermático/fisiopatología
18.
Clin Chim Acta ; 547: 117415, 2023 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-37271272

RESUMEN

BACKGROUND: Great concerns have been raised on SARS-CoV-2 impact on men's andrological well-being, and many studies have attempted to determine whether SARS-CoV-2 is present in the semen and till now the data are unclear and somehow ambiguous. However, these studies used quantitative real-time (qRT) PCR, which is not sufficiently sensitive to detect nucleic acids in clinical samples with a low viral load. METHODS: The clinical performance of various nucleic acid detection methods (qRT-PCR, OSN-qRT-PCR, cd-PCR, and CBPH) was assessed for SARS-CoV-2 using 236 clinical samples from laboratory-confirmed COVID-19 cases. Then, the presence of SARS-CoV-2 in the semen of 12 recovering patients was investigated using qRT-PCR, OSN-qRT-PCR, cd-PCR, and CBPH in parallel using 24 paired semen, blood, throat swab, and urine samples. RESULTS: The sensitivity and specificity along with AUC of CBPH was markedly higher than the other 3methods. Although qRT-PCR, OSN-qRT-PCR and cdPCR detected no SARS-CoV-2 RNA in throat swab, blood, urine, and semen samples of the 12 patients, CBPH detected the presence of SARS-CoV-2 genome fragments in semen samples, but not in paired urine samples, of 3 of 12 patients. The existing SARS-CoV-2 genome fragments were metabolized over time. CONCLUSIONS: Both OSN-qRT-PCR and cdPCR had better performance than qRT-PCR, and CBPH had the highest diagnostic performance in detecting SARS-CoV-2, which contributed the most improvement to the determination of the critical value in gray area samples with low vrial load, which then provides a rational screening strategy for studying the clearance of coronavirus in the semen over time in patients recovering from COVID-19. Although the presence of SARS-CoV-2 fragments in the semen was demonstrated by CBPH, COVID-19 is unlikely to be sexually transmitted from male partners for at least 3 months after hospital discharge.


Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , Masculino , SARS-CoV-2/genética , COVID-19/diagnóstico , Semen/química , Prueba de COVID-19 , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , ARN Viral/genética
19.
Parasitology ; 139(4): 522-9, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22309838

RESUMEN

The aim of this study was to evaluate the therapeutic effects of osteopontin neutralization treatment on schistosome-induced liver injury in BALB/C mice. We randomly divided 100 BALB/C mice into groups A, B, C, D and group E. Mice in all groups except group A were abdominally infected with schistosomal cercariae to induce a schistosomal hepatopathological model. Mice in group C, D and group E were respectively administered with praziquantel, praziquantel plus colchicine and praziquantel plus neutralizing osteopontin antibody. We extracted mouse liver tissues at 3 and 9 weeks after the 'stool-eggs-positive' day, observed liver histopathological changes by haematoxylin-eosin and Masson trichrome staining and detected the expression of osteopontin, alpha-smooth muscle actin (α-SMA) and transforming growth factor-beta (TGF-ß1) by immunohistochemistry, RT-PCR and Western blot. We found that praziquantel plus neutralizing osteopontin antibody treatment significantly decreased the granuloma dimension, the percentage of collagen and the expression of osteopontin, α-SMA and TGF-ß1 compared to praziquantel plus colchicine treatment in both the acute and chronic stage of schistosomal liver damage (P<0·05). So we believe that the combined regimen of osteopontin immunoneutralization and anti-helminthic treatment can reduce the granulomatous response and liver fibrosis during the schistosomal hepatopathologic course.


Asunto(s)
Anticuerpos Neutralizantes/uso terapéutico , Cirrosis Hepática/tratamiento farmacológico , Osteopontina/inmunología , Praziquantel/uso terapéutico , Schistosoma japonicum/efectos de los fármacos , Esquistosomiasis Japónica/tratamiento farmacológico , Animales , Anticuerpos Neutralizantes/inmunología , Arteriosclerosis , Quimioterapia Combinada , Femenino , Granuloma/tratamiento farmacológico , Granuloma/metabolismo , Granuloma/patología , Síndromes de Inmunodeficiencia , Hígado/efectos de los fármacos , Hígado/parasitología , Hígado/patología , Cirrosis Hepática/inmunología , Cirrosis Hepática/metabolismo , Cirrosis Hepática/patología , Ratones , Ratones Endogámicos BALB C , Síndrome Nefrótico , Osteocondrodisplasias , Osteopontina/metabolismo , Praziquantel/farmacología , Enfermedades de Inmunodeficiencia Primaria , Embolia Pulmonar , Schistosoma japonicum/patogenicidad , Esquistosomiasis Japónica/inmunología , Esquistosomiasis Japónica/metabolismo , Esquistosomiasis Japónica/parasitología , Factor de Crecimiento Transformador beta1/metabolismo , Resultado del Tratamiento
20.
Appl Microbiol Biotechnol ; 93(5): 2193-203, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21847510

RESUMEN

Knowledge about methanotrophs and their activities is important to understand the microbial mediation of the greenhouse gas CH(4) under climate change and human activities in terrestrial ecosystems. The effects of simulated warming and sheep grazing on methanotrophic abundance, community composition, and activity were studied in an alpine meadow soil on the Tibetan Plateau. There was high abundance of methanotrophs (1.2-3.4 × 10(8) pmoA gene copies per gram of dry weight soil) assessed by real-time PCR, and warming significantly increased the abundance regardless of grazing. A total of 64 methanotrophic operational taxonomic units (OTUs) were obtained from 1,439 clone sequences, of these OTUs; 63 OTUs (98.4%) belonged to type I methanotrophs, and only one OTU was Methylocystis of type II methanotrophs. The methanotroph community composition and diversity were not apparently affected by the treatments. Warming and grazing significantly enhanced the potential CH(4) oxidation activity. There were significantly negative correlations between methanotrophic abundance and soil moisture and between methanotrophic abundance and NH(4)-N content. The study suggests that type I methanotrophs, as the dominance, may play a key role in CH(4) oxidation, and the alpine meadow has great potential to consume more CH(4) under future warmer and grazing conditions on the Tibetan Plateau.


Asunto(s)
Bacterias/clasificación , Bacterias/metabolismo , Biota , Metano/metabolismo , Microbiología del Suelo , Amoníaco/análisis , Animales , ADN Bacteriano/química , ADN Bacteriano/genética , Datos de Secuencia Molecular , Oxidación-Reducción , Reacción en Cadena en Tiempo Real de la Polimerasa , Análisis de Secuencia de ADN , Ovinos , Suelo/química , Temperatura , Tibet
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA