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121.

Objectives

To compare the Conventional, Specified, Expanded and Combined Apgar scoring systems in predicting birth asphyxia and the adverse early neurologic outcomes.

Methods

This prospective cohort study was conducted on 464 admitted neonates. In the delivery room, after delivery the umbilical cord was double clamped and a blood samples was obtained from the umbilical artery for blood gas analysis, meanwhile on the 1- , 5- and 10- minutes Conventional, Specified, Expanded, and Combined Apgar scores were recorded. Then the neonates were followed and intracranial ultrasound imaging was performed, and the following information were recorded: the occurrence of birth asphyxia, hypoxic Ischemic Encephalopathy (HIE), intraventricular hemorrhage (IVH), and neonatal seizure.

Results

The Combined-Apgar score had the highest sensitivity (97%) and specificity (99%) in predicting birth asphyxia, followed by the Specified-Apgar score that was also highly sensitive (95%) and specific (97%). The Expanded-Apgar score was highly specific (95%) but not sensitive (67%) and the Conventional-Apgar score had the lowest sensitivity (81%) and low specificity (81%) in predicting birth asphyxia. When adjusted for gestational age, only the low 5-minute Combined-Apgar score was independently associated with the occurrence of HIE (B = 1.61, P = 0.02) and IVH (B = 2.8, P = 0.01).

Conclusions

The newly proposed Combined-Apgar score is highly sensitive and specific in predicting birth asphyxia and also is a good predictor of the occurrence of HIE and IVH in asphyxiated neonates.  相似文献   
122.
Actinomycetes isolated from Iran soil habitats were tested for the capacity to produce compounds which can protect neurons from cell death generated by oxidative stress in NT2 neurons. Confirmation of our initial hit was accomplished via the determination of amyloid β level using the enzyme-linked immunosorbent assay test. The most interesting amyloid β formation inhibitor discovered in our study was a secondary metabolite which was produced by strain HM45. This bioactive strain was identified as a strain of Streptomyces antibioticus DSM 40234 using polyphasic approach. The strain HM45 was deposited in Deutsche Sammlung von Mikroorganismen und Zellkulturen as S. antibioticus DSM 41955 and University of Tehran Microorganisms Sollection as S. antibioticus UTMC 00105. This work is the first report on efficiency of an actinomycete metabolite in prohibition of neurons death caused by amyloid β formation.  相似文献   
123.
The type and frequency of structural hemoglobin variants and their hematological and molecular characteristics were identified using PCR-RFLP and sequencing techniques in 66 individuals from 33 unrelated families who referred to the two clinics of Kermanshah University of Medical Sciences from 2005 to 2006. We detected 28 subjects carrier for Hb D-Punjab (42.4%), 21 individuals carrier of Hb Q-Iran (31.8%), 12 subjects heterozygous for Hb Setif (18.2%), four cases with sickle cell disease (6.1%), and one case with Hb C (1.5%). All βS genes (4 genes) were linked to the Benin haplotype with negative Taq I site 5′ to γA gene. All βD-Punjab genes (29 genes) were in linkage disequilibrium with haplotype I. The only βC chromosome was linked to haplotype II. Both β0-thalassemia chromosomes with CD15 (G → A) mutation had haplotype background I. Three β+-thalassemia chromosomes with IVSI.110 (G → A) mutation were associated with haplotype I [+ − − − − + +]. In turn, the three β-thalassemia chromosomes with IVS II.1 G → A mutation were associated with atypical haplotype [− + + + + + −]. Hematological indices of carriers of Hb D-Punjab, Hb Q-Iran and Hb Setif were lower than those reported for normal individuals. For the first time, we have reported the haplotype background of βS gene among Kurdish population of Iran. Our results revealed that Hb D-Punjab is the most prevalent β-globin chain structural variant in this area and that is followed in frequency by an α-chain variant, Hb Q-Iran. The result of present study is useful for clinical management and the establishment of screening programmes in Western Iran.  相似文献   
124.
125.
A new bisindole alkaloid, bisleuconothine A (1) consisting of an eburnane–aspidosperma type skeleton, was isolated from the bark of Leuconotis griffithii. The structure including absolute stereochemistry was elucidated on the basis of 2D NMR data and X-ray analysis. Bisleuconothine A (1) showed cell growth inhibitory activity against various human cancer cell lines.  相似文献   
126.
In this study, responses of wild species of potato to NaCl stress were investigated in vitro. In S. stoloniferum and S. bulbosum, length of the shoot, fresh and dry weight, photosynthetic pigments, K+ concentration, K+/Na+ ratio, ascorbate pool, anthocyanin, and phenolic and flavonoid compounds were decreased in response to salinity. In these species, salinity increased the level of Na+, lipid peroxidation, proline and ion leakage percentage. In S. acaule, the length of the shoot, and fresh and dry weight were not affected by salinity. Photosynthetic pigments, Na+ concentration, proline, flavonoid and phenolic compounds quantities were increased and K+/Na+ ratio were decreased. K+ concentration, lipid peroxidation, ascorbate pool, anthocyanin and ion leakage were not changed by NaCl stress. Superoxide dismutase, guaiacol peroxidase, ascorbate peroxidase and catalase activities were increased in all species. The results suggest that the non-enzymatic antioxidant capacity in S. acaule (salt tolerant) is more important than the enzymatic antioxidant capacity in comparison with the other species.  相似文献   
127.
Recombinant tissue plasminogen activator (rt-PA) is one of the most important thrombolytic agents for treating cardiovascular obstructions such as stroke. Glycoprotein rt-PA is a serine protease, consisting of 527 amino acids of which 35 are cysteine residues. A variety of recombinant protein expression systems have been developed for heterologous gene expression in prokaryotic and eukaryotic hosts. In recent years, Leishmania tarentolae has been considered because of its safety aspects and special attributes in expression of complex proteins. In this study, two expression cassettes, each one including two copies of t-PA cDNA, were used for integration into the L. tarentolae genome by electroporation. Transformed clones were selected in the presence of appropriate antibiotics. Expression of active rt-PA was confirmed by Western blot and Zymography tests. Real-time PCR analysis was applied to investigate the presence of multiple t-PA gene copies in the parasite genome. Correlation of t-PA gene dosage and production rate was confirmed with real-time PCR. It was shown that the expression level of rt-PA in L. tarentolae is at least 480 IU/mL of culture media. This concentration of rt-PA is seven times higher than what was reported in previous studies in L. tarentolae and some other eukaryotic systems.  相似文献   
128.
The aim of the present study was to elaborate cryopreservation methods for ex situ conservation of tench. Success of cryopreservation was tested during two series of experiments. The first set of experiments studied the effects of two types of cryoprotectants (DMSO and a combination of DMSO with propanediol at ratio 1:1) at concentrations of 8 and 10% and three different equilibration times in two different immobilization solutions (IS) (Kurokura 180 and Kurokura) before freezing (0.0, 2.0 and 4.0h after T(0)). The K4 cooling programme was used to freeze 1ml of cryoextended sperm using 1.8ml cryotubes. Main monitored parameter was hatching rate after using of cryopreserved sperm. The second set of experiments studied the volume effect of 0.5, 1 and 5ml straws and compared these with 1.8ml cryotubes as well as the effect of the cooling programme (K4 and L1). Following the results of the first study, a combination of DMSO and propanediol (ratio 1:1) at concentration of 10% was added to extended sperm in Kurokura 180 IS. Main monitored parameter was hatching rate after using cryopreserved sperm, supplementary parameters were sperm velocity and motility percentage assessed at 10s post-activation. Sperm was collected directly into IS and stored at 4 degrees C for 2.5h. Thereafter were sperm samples pooled, equlibred in IS (first set of experiments) or directly mixed with cryoprotectants (DMSO or a mixture of DMSO with propanediol at ratio 1:1) and transferred to 1.8ml cryotubes or straws (0.5, 1 and 5ml). Then the cryotubes/straws were directly transferred to pre-programmed PLANER Kryo 10 series III and cooled using two different cooling programmes including a slow cooling programme (a) named K4 (from +4 to -9 degrees C at a rate of 4 degrees Cmin(-1) and then from -9 to -80 degrees C at a rate of 11 degrees Cmin(-1)) and a rapid cooling programme (b) named L1 (directly from +4 to -80 degrees C at a rate of 20 degrees Cmin(-1)). Both slow (K4) and rapid (L1) cooled samples were held 6min at -80 degrees C. Finally, samples were transferred into liquid N(2). The frozen spermatozoa were thawed in a water bath (40 degrees C) according to the frozen volume and checked for fertilization and hatching rates. Percentage of sperm motility and sperm velocity were measured using video recorded frames. ANOVA showed a significant influence of frozen and fresh sperm in all treatments. The hatching rates of 33.8% were obtained when sperm was equilibrated for 0h before freezing in IS of Kurokura 180 and frozen with a 10% of mixture 1:1 of DMSO and propanediol into straws of 5ml and cooled using program L1. The velocity of frozen-thawed spermatozoa ranged from 31 to 46microms(-1) and in post-thawed sperm was not significantly different according to frozen sperm volume, but a higher velocity was obtained when sperm was fast frozen using programme L1. A large volume of frozen sperm could reveal the best procedure for freezing, but also for simulating methods of artificial propagation for future practical use of frozen tench sperm at a large scale.  相似文献   
129.
Transgenic trees currently are being produced by Agrobacterium-mediated transformation and biolistics. Since trees are particularly suited for long-term evaluations of the impact of the technology, Prunus subhirtella autumno rosa (PAR) was chosen as model fruit tree species and transformed with a reporter gene (uidA) under the control of the 35S promoter. Using Southern and GUS fluorometric techniques, we compared transgene copy numbers and observed stability of transgene expression levels in 34 different transgenic plants, grown under in vitro, greenhouse and screenhouse conditions, over a period of 9 years. An influence of grafting on gene expression was not observed. No silenced transgenic plant was detected. Overall, these results suggest that transgene expression in perennial species, such as fruit trees, remains stable in time and space, over extended periods and in different organs, confirming the value of PAR as model species to study season-dependent regulation in mature stone fruit tissues. While the Agrobacterium-derived Prunus transformants contained one to two copies of the transgenes, 91% of the transgenic events also contained various lengths of the bacterial plasmid backbone, indicating that the Agrobacterium-mediated transformation is not as precise as previously perceived. The implications for public acceptance and future applications are discussed.  相似文献   
130.
The Punung Fauna is a key component in the biostratigraphic sequence of Java. It represents the most significant faunal turnover on the island in the last 1.5 million years, when Stegodon and other archaic mammal species characteristic of earlier Faunal stages were replaced by a fully modern fauna that included rainforest-dependent species such as Pongo pygmaeus (orangutan). Here, we report the first numerical ages for the Punung Fauna obtained by luminescence and uranium-series dating of the fossil-bearing deposits and associated flowstones. The Punung Fauna contained in the dated breccia is of early Last Interglacial age (between 128+/-15 and 118+/-3 ka). This result has implications for the age of the preceding Ngandong Fauna, including Homo erectus remains found in the Ngandong Terrace, and for the timing of Homo sapiens arrival in Southeast Asia, in view of claims for a modern human tooth associated with the Punung breccia.  相似文献   
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