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1.
Alkaline phosphatase (ALP) is rapidly induced in the uterine subepithelial stroma after a natural or artificial decidual stimulus. During gestation ALP-specific activity peaked at Day 7 to 8 (Day 1 is day of detection of the copulation plug) followed by a rapid decline to control levels by Day 9. This elevation in enzyme activity was preceded by an 8-fold induction of a 2.6 kilobase (kb) mRNA. This mRNA was not preferentially localized to implantation sites. ALP activity was detected in the placenta at Day 9 and reached maximum specific activity at Day 19. The placental ALP was also encoded by a 2.6 kb mRNA. Uterine and placental ALPs were inhibited to the same extent by levamisole, L-tryptophan and homoarginine. The calculated Ki values for these inhibitors were not statistically different between the uterine and placental forms. Km values towards the substrate p-nitrophenylphosphate, however, were statistically different between the uterine and placental forms. Both uterine and placental ALPs were stimulated 3-4-fold by addition of 2 mM-Mg2+. Electrophoretic mobilities on SDS polyacrylamide gel, where the enzyme migrated as a single band, were the same. The uterine form, however, could be distinguished from the placental isoenzyme by separation on non-denaturing polyacrylamide gels; the uterine form had a single zone of activity which migrated with an intermediate mobility between the two zones of activity detected for the placental enzyme. These differences in mobility could be ascribed to the sialic acid content of the enzyme because treatment with neuraminidase resulted in the uterine and placental forms migrating with comparable but slower mobilities in non-denaturing gels.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
2.
Arduous efforts have been made in the last three decades to elucidate the role of insulin in the brain. A growing number of evidences show that insulin is involved in several physiological function of the brain such as food intake and weight control, reproduction, learning and memory, neuromodulation and neuroprotection. In addition, it is now clear that insulin and insulin disturbances particularly diabetes mellitus may contribute or in some cases play the main role in development and progression of neurodegenerative and neuropsychiatric disorders. Focusing on the molecular mechanisms, this review summarizes the recent findings on the involvement of insulin dysfunction in neurological disorders like Alzheimer’s disease, Parkinson’s disease and Huntington’s disease and also mental disorders like depression and psychosis sharing features of neuroinflammation and neurodegeneration.  相似文献   
3.
In this study, the diversity of Plasmodium vivax populations circulating in Pakistan and Iran has been investigated by using circumsporozoite protein (csp) and merozoite surface proteins 1 and 3α (msp-1 and msp-3α) genes as genetic markers. Infected P. vivax blood samples were collected from Pakistan (n = 187) and Iran (n = 150) during April to October 2008, and were analyzed using nested-PCR/RFLP and sequencing methods. Genotyping pvmsp-1 (variable block 5) revealed the presence of type 1, type 2 and recombinant type 3 allelic variants, with type 1 predominant, in both study areas. The sequence analysis of 33 P. vivax isolates from Pakistan and 30 from Iran identified 16 distinct alleles each, with one allele (R-8) from Iran which was not reported previously. Genotyping pvcsp gene also showed that VK210 type is predominant in both countries. Moreover, based on the size of amplified fragment of pvmsp-3α, three major types: type A (1800 bp), type B (1500 bp) and type C (1200 bp), were distinguished among the examined isolates that type A was predominant among Pakistani (72.7%) and Iranian (77.3%) parasites. PCR/RFLP products of pvmsp-3α with HhaI and AluI have detected 40 and 39 distinct variants among Pakistani and Iranian examined isolates, respectively. Based on these three studied genes, the rate of combined multiple genotypes were 30% and 24.6% for Pakistani and Iranian P. vivax isolates, respectively. These results indicate an extensive diversity in the P. vivax populations in both studies.  相似文献   
4.
International Journal of Peptide Research and Therapeutics - Acinetobacter baumannii is an important pathogen responsible for nosocomial infections worldwide. Trimeric autotransporters, the...  相似文献   
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6.
Hypothesis/objective: Prolonged QT interval is an index of propensity for dangerous ventricular tachyarrhythmias. The aim of this article is to establish an automatic algorithm for QT interval measurement.

Method: The proposed method is based on the continuous wavelet transform. In this method, the concepts of the rescaled wavelet coefficients and dominant scales of the electrocardiogram (ECG) components are used to perform detection of ECG characteristic points. A new concept of rescaled maximum energy density is introduced so as to perform the estimation of the QT interval.

Results and conclusion: We have applied the algorithm to the PTB database of the Physiobank?Physionet in lead II. Then, the results were evaluated using pertinent reference QT. The criterion used for evaluation of the method's performance is the root mean square (RMS) error. The method approached the RMS error of 27.89 ms for 549 subjects. The proposed method is fast, simple and is applicable to a wide range of ECG cardio cycle morphologies.  相似文献   
7.
ErbB-3 (HER-3) receptor is involved in tumor progression and resistance to therapy. Development of specific inhibitors impairing the activity of ErbB-3 is an attractive tool for cancer therapeutics. MP-RM-1, a murine monoclonal antibody targeting human ErbB-3, has shown anticancer activity in preclinical models. With the aim to provide novel candidates for clinical use, we have successfully generated a humanized version of MP-RM-1. The humanized antibody, named EV20, abrogates both ligand-dependent and ligand-independent receptor signaling of several tumor cell types, strongly promotes ErbB-3 down-regulation, and efficiently and rapidly internalizes into tumor cells. Furthermore, treatment with EV20 significantly inhibits growth of xenografts originating from prostatic, ovarian, and pancreatic cancers as well as melanoma in nude mice. In conclusion, we provide a novel candidate for ErbB-3-targeted cancer therapy.  相似文献   
8.
Nitric oxide (NO) is a hormone that connects numerous reactions in plant cells under normal and environmental stress conditions. The application of 100 µM NO as sodium nitroprusside (SNP; NO donor) applied individually or in combination with N or S in different combinations (i.e. 100 mg N or S kg−1 soil applied at the time of sowing [100 N + 100S]0d or with split, 50 mg N or S kg−1 soil at the time of sowing and similar dose at 20 d after sowing [50 N + 50S]0d + [50 N + 50S]20d) was tested to alleviate salt stress in mustard (Brassica juncea L.). Application of 100 µM NO plus split application of N and S more significantly promoted stomatal behavior, photosynthetic and growth performance in the absence of salt stress and maximally alleviated effects of salt stress through increased N- and S-use efficiency, proline and antioxidant system. The combined application of N and S at the time of sowing was lesser effective in promoting photosynthesis and growth under salt or no salt stress conditions in presence or absence of NO. The study suggests that salt stress effects on the photosynthetic performance are mitigated more efficiently when NO was applied together with the split application of N and S given at two stages, and the photosynthetic activity was promoted under salt stress through increased N and S assimilation and antioxidant system. This strategy may be adopted in agricultural system for overcoming salt stress effects on performance of mustard.  相似文献   
9.
The diamondback moth (DBM), Plutella xylostella (L.) (Lepidoptera: Yponomeutidae), is the most serious pest of cauliflower fields in central Iran and its control is primarily based on pesticide sprays. Over the past years, a number of new pesticide compounds were introduced onto the market and some of them may cause adverse effects on natural populations of parasitoids associated with DBM. Excessive use of insecticides against the pest did not produce satisfactory results but has caused concerns about environmental pollution and increased pest resistance to chemicals. This research aims to study natural parasitism of pest on different cauliflower cultivars in the fields of south of Tehran. Dominant species of parasitoids include Diadegma anurum, Cotesia plutellae and Oomyzus sokolowskii. The highest parasitism rate was observed by D. anurum that was recorded on Buris cultivar (19.92?±?1.06) and White cloud cultivar (16.20?±?1.49) and the lowest parasitism rate was observed on Snow crown cultivar (3.42) and SG cultivar (5.00) during the season.  相似文献   
10.
The diamondback moth (DBM), Plutella xylostella (L.) (Lep., Plutellidae), is one of the most important pests of oilseed rape, Brassica napus L., in the world. In this study, resistance of oilseed rape cultivars to DBM was evaluated in fields of Tehran based on injury rate of the cultivars. To evaluate cultivar resistance, 19 cultivars of oilseed rape were planted in randomised complete-block design with three replications. Total experiments were conducted in experimental field of Shahed University. Results showed that DBM had activity on the plants during season and peak of the injury occurred on 27 May. Results indicated that the total of oilseed rape cultivar was spotty. Statistical analysis showed that there was significant difference among determined characteristics in all cultivars. The highest and lowest numbers of holes in the leaf were observed in Midas, Karaj3, Zarfam and Hyola420, Hyola308 cultivars, respectively, in sampling of the end growth. Opera and Midas cultivars have the highest percentage of leaf infestation and the lowest percentage of leaf infestation was observed in Hyola420 and Hyola308. Also, Karaj3 and Zarfam cultivars have the highest percentage of meristem infestation and the lowest percentage of meristem infestation was observed in Licard and Hyola420 cultivars. Based on peak of the injury rate and importance of meristem injury, Hyola420 and Hyola308 cultivars were relatively resistant to DBM, and Karaj3 and Zarfam were relatively sensitive to DBM.  相似文献   
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