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21.
New approaches for high-yield purification of Müllerian inhibiting substance improve its bioactivity
Lorenzo HK Teixeira J Pahlavan N Laurich VM Donahoe PK MacLaughlin DT 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2002,766(1):89-98
We have established a new method to purify Müllerian inhibiting substance (MIS) with higher purity and recovery over existing procedures. Recombinant human MIS was expressed in Chinese hamster ovary cells and secreted into chemically defined serum-free media. The secreted products were concentrated by either precipitation with ammonium sulfate or lectin-affinity chromatography, each of which was followed by anion-exchange chromatography. Further separation of the active carboxy-terminal domain of MIS was achieved after cleavage by plasmin followed by lectin-affinity chromatography. This method may be applicable to other members of the transforming growth factor beta family with which MIS shares sequence homology. 相似文献
22.
Mohammadreza Maghami Hashim Hizam Chandima Gomes Shahrooz Hajighorbani Nima Rezaei 《PloS one》2015,10(8)
Pollution in Southeast Asia is a major public energy problem and the cause of energy losses. A significant problem with respect to this type of pollution is that it decreases energy yield. In this study, two types of photovoltaic (PV) solar arrays were used to evaluate the effect of air pollution. The performance of two types of solar arrays were analysed in this research, namely, two units of a 1 kWp tracking flat photovoltaic (TFP) and two units of a 1 kWp fixed flat photovoltaic arrays (FFP). Data analysis was conducted on 2,190 samples at 30 min intervals from 01st June 2013, when both arrays were washed, until 30th June 2013. The performance was evaluated by using environmental data (irradiation, temperature, dust thickness, and air pollution index), power output, and energy yield. Multiple regression models were predicted in view of the environmental data and PV array output. Results showed that the fixed flat system was more affected by air pollution than the tracking flat plate. The contribution of this work is that it considers two types of photovoltaic arrays under the Southeast Asian pollution 2013. 相似文献
23.
Amirzargar A Shahram F Nikoopour E Rezaei N Saeedfar K Ziaei N Davatchi F 《European cytokine network》2010,21(4):292-296
Beh?et's disease (BD) is a chronic, systemic disease, characterized by oral and genital lesions, and ocular inflammation. There is evidence indicating altered levels of proinflammatory cytokines, such as interleukin (IL)-6 and tumor necrosis factor alpha (TNF-α) in patients with BD. This study involved 150 patients with BD and 140 healthy controls, and investigated the role of proinflammatory cytokine gene polymorphisms in the disease. The frequency of the TNF-α (-238) G/G genotype was significantly higher in the patient group, compared to the controls (p < 0.001), whilst the G/A genotype was significantly lower in the patients with BD (p < 0.001). Patients with BD showed a significant increase in the TNF-α (- 308, - 238) GG haplotype (p < 0.001), whilst there was a significant decrease in the GA haplotype (p < 0.001). The heterozygous, IL-6 (- 174) C/G genotype (p = 0.005), and the IL-6 (- 174, nt565) haplotype CG (p < 0.001), were significantly decreased in the patient group. The increased production of proinflammatory cytokines in BD could be a consequence of specific, cytokine gene polymorphisms. Particular genotypes and haplotypes in TNF-α were over-represented in BD, which may, in turn, predispose individuals to this disease. 相似文献
24.
Nima Dehghani Claude Bédard Sydney S. Cash Eric Halgren Alain Destexhe 《Journal of computational neuroscience》2010,29(3):405-421
The resistive or non-resistive nature of the extracellular space in the brain is still debated, and is an important issue
for correctly modeling extracellular potentials. Here, we first show theoretically that if the medium is resistive, the frequency
scaling should be the same for electroencephalogram (EEG) and magnetoencephalogram (MEG) signals at low frequencies (<10 Hz).
To test this prediction, we analyzed the spectrum of simultaneous EEG and MEG measurements in four human subjects. The frequency
scaling of EEG displays coherent variations across the brain, in general between 1/f and 1/f
2, and tends to be smaller in parietal/temporal regions. In a given region, although the variability of the frequency scaling
exponent was higher for MEG compared to EEG, both signals consistently scale with a different exponent. In some cases, the
scaling was similar, but only when the signal-to-noise ratio of the MEG was low. Several methods of noise correction for environmental
and instrumental noise were tested, and they all increased the difference between EEG and MEG scaling. In conclusion, there
is a significant difference in frequency scaling between EEG and MEG, which can be explained if the extracellular medium (including
other layers such as dura matter and skull) is globally non-resistive. 相似文献
25.
To date, the majority of plant small RNAs (sRNA) have been identified in rice, poplar and Arabidopsis. To identify novel tomato sRNAs potentially involved in tomato specific processes such as fruit development and/or ripening,
we cloned 4,018 sRNAs from tomato fruit tissue at the mature green stage. From this pool of sRNAs, we detected tomato homologues
of nine known miRNAs, including miR482; a poplar miRNA not conserved in Arabidopsis or rice. We identified three novel putative miRNAs with flanking sequence that could be folded into a stem-loop precursor
structure and which accumulated as 19-24nt RNA. One of these putative miRNAs (Put-miRNA3) exhibited significantly higher expression
in fruit compared with leaf tissues, indicating a specific role in fruit development processes. We also identified nine sRNAs
that accumulated as 19–24nt RNA species in tomato but genome sequence was not available for these loci. None of the nine sRNAs
or three putative miRNAs possessed a homologue in Arabidopsis that had a precursor with a predicted stem-loop structure or that accumulated as a sRNA species, suggesting that the 12 sRNAs
we have identified in tomato may have a species specific role in this model fruit species.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
26.
Yu Zhao Mona C Majid Jennifer M Soll Joshua R Brickner Sebastian Dango Nima Mosammaparast 《The EMBO journal》2015,34(12):1687-1703
Repair of DNA alkylation damage is critical for genomic stability and involves multiple conserved enzymatic pathways. Alkylation damage resistance, which is critical in cancer chemotherapy, depends on the overexpression of alkylation repair proteins. However, the mechanisms responsible for this upregulation are unknown. Here, we show that an OTU domain deubiquitinase, OTUD4, is a positive regulator of ALKBH2 and ALKBH3, two DNA demethylases critical for alkylation repair. Remarkably, we find that OTUD4 catalytic activity is completely dispensable for this function. Rather, OTUD4 is a scaffold for USP7 and USP9X, two deubiquitinases that act directly on the AlkB proteins. Moreover, we show that loss of OTUD4, USP7, or USP9X in tumor cells makes them significantly more sensitive to alkylating agents. Taken together, this work reveals a novel, noncanonical mechanism by which an OTU family deubiquitinase regulates its substrates, and provides multiple new targets for alkylation chemotherapy sensitization of tumors. 相似文献
27.
First Report of Curtobacterium flaccumfaciens pv. flaccumfaciens Causing Cowpea Bacterial Wilt in Iran
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Ebrahim Osdaghi Babak Pakdaman Sardrood Majed Bavi Nima Akbari Oghaz Shabnam Kimiaei Saideh Hadian 《Journal of Phytopathology》2015,163(7-8):653-656
During surveys in cowpea fields of Marand County, East Azerbaijan province, Iran, in the summer of 2013, a suspected bacterial disease was observed on cowpea leaves as tan spots and interveinal necrotic lesions surrounded by chlorotic margins. The disease was of high incidence where some fields had been fully destroyed and severity of the disease in some fields had reached up to 70%. Gram‐positive, yellow‐pigmented, coryneform bacteria were isolated from infected leaves. Pathogenicity of isolates was confirmed on 20‐day‐old cowpea (cv. Khoy) plants, and they were identified as Curtobacterium flaccumfaciens pv. flaccumfaciens based on biochemical test results confirmed using specific PCR primers. This is the first report of C. flaccumfaciens pv. flaccumfaciens, the causal agent of cowpea bacterial wilt in Iran. 相似文献
28.
Mohammed Arifullah Chiruvella Kishore K. Namsa Nima D. Ghanta Rama Gopal 《Physiology and Molecular Biology of Plants》2015,21(3):417-424
Physiology and Molecular Biology of Plants - Bixa orellana L. (Bixaceae) is a multipurpose tree grown for the production of commercially important dyes. In the present study, an efficient,... 相似文献
29.
Nima Taha Jing Zhang Reza Rafie Rupesh Ranjan Salima Qamruddin Tasneem Z Naqvi 《Cardiovascular ultrasound》2011,9(1):1-12
Background
Biventricular (Biv) pacemaker echo optimization has been shown to improve cardiac output however is not routinely used due to its complexity. We investigated the role of a simple method involving computerized pre-ejection time (PEP) assessment by radial artery tonometry in guiding Biv pacemaker optimization.Methods
Blinded echo and radial artery tonometry were performed simultaneously in 37 patients, age 69.1 ± 12.8 years, left ventricular (LV) ejection fraction (EF) 33 ± 10%, during Biv pacemaker optimization. Effect of optimization on echo derived velocity time integral (VTI), ejection time (ET), myocardial performance index (MPI), radial artery tonometry derived PEP and echo-radial artery tonometry derived PEP/VTI and PEP/ET indices was evaluated.Results
Significant improvement post optimization was achieved in LV ET (286.9 ± 37.3 to 299 ± 34.6 ms, p < 0.001), LV VTI (15.9 ± 4.8 cm to 18.4 ± 5.1 cm, p < 0.001) and MPI (0.57 ± 0.2 to 0.45 ± 0.13, p < 0.001) and in PEP (246.7 ± 36.1 ms to 234.7 ± 35.5 ms, p = 0.003), PEP/ET (0.88 ± 0.21 to 0.79 ± 0.17, p < 0.001), and PEP/VTI (17.3 ± 7 to 13.78 ± 4.7, p < 0.001). The correlation between comprehensive echo Doppler and radial artery tonometry-PEP guided optimal atrioventricular delay (AVD) and optimal interventricular delay (VVD) was 0.75 (p < 0.001) and 0.69 (p < 0.001) respectively. In 29 patients with follow up assessment, New York Heart Association (NYHA) class reduced from 2.5 ± 0.8 to 2.0 ± 0.9 (p = 0.004) at 1.8 ± 1.4 months.Conclusion
An acute shortening of PEP by radial artery tonometry occurs post Biv pacemaker optimization and correlates with improvement in hemodynamics by echo Doppler and may provide a cost-efficient approach to assist with Biv pacemaker echo optimization. 相似文献30.