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91.
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92.
Since the first in vitro fertilization (IVF) in human, the number of patients using Assisted Reproductive Technologies (ART) has increased tremendously. ART technologies have increased in number and their spectrum has also widened. The first IVF babies are now more than 20 years old. All the retrospective analyses have demonstrated that the obstetrical and pediatrical impact has not really affected single births. The main problems observed occur with multiple pregnancies, including high costs for the couples and for society. The decrease in the number of embryos transferred has improved the situation and moreover does not impair the final results. IntraCytoplasmic Sperm Injection (ICSI) is a more debatable and questionable technique with a real negative genetic impact. The main problem is chromosome abnormalities more specifically related to the sex chromosomes. The question of a systematic genetic work-up on the patients entering ICSI programs is discussed. No negative impact of cryopreservation has been demonstrated even though some controversy arises from time to time. Pre-implantation Genetic Diagnosis (PGD) is now a interesting tool for patients carrying genetic defects. Blastocyst biopsy now has a future role in reproductive medicine. Gender selection through sperm sorting is also now a reality. As with the other developing bio-technologies related to reproduction, there are ethical questions. The decisions concerning these technologies do not belong solely to scientists but are rather a matter for society to decide.  相似文献   
93.
Neurological diseases such as Alzheimer’s and Parkinson’s diseases are incurable progressive neurological disorders caused by the degeneration of neuronal cells and characterized by motor and non-motor symptoms. Curcumin, a turmeric product, is an anti-inflammatory agent and an effective reactive oxygen and nitrogen species scavenging molecule. Hydrogen peroxide (H2O2) is the main source of oxidative stress, which is claimed to be the major source of neurological disorders. Hence, in this study we aimed to investigate the effect of curcumin on Ca2+ signaling, oxidative stress parameters, mitochondrial depolarization levels and caspase-3 and -9 activities that are induced by the H2O2 model of oxidative stress in SH-SY5Y neuronal cells. SH-SY5Y neuronal cells were divided into four groups namely, the control, curcumin, H2O2, and curcumin?+?H2O2 groups. The dose and duration of curcumin and H2O2 were determined from published data. The cells in the curcumin, H2O2, and curcumin?+?H2O2 groups were incubated for 24?h with 5?µM curcumin and 100?µM H2O2. Lipid peroxidation and cytosolic free Ca2+ concentrations were higher in the H2O2 group than in the control group; however, their levels were lower in the curcumin and curcumin?+?H2O2 groups than in the H2O2 group alone. Reduced glutathione (GSH) and glutathione peroxidase (GSH-Px) values were lower in the H2O2 group although they were higher in the curcumin and curcumin?+?H2O2 groups than in the H2O2 group. Caspase-3 activity was lower in the curcumin group than in the H2O2 group. In conclusion, curcumin strongly induced modulator effects on oxidative stress, intracellular Ca2+ levels, and the caspase-3 and -9 values in an experimental oxidative stress model in SH-SY5Y cells.  相似文献   
94.
Tordylium is a medium‐sized genus characterized by an annual habit, 1–3‐pinnate leaves, dorsally compressed mericarps, and thickened mericarp margins. Eighteen Tordylium species occur in Turkey, of which seven are endemic. Although the morphology of the genus is well known, evolutionary relationships among its species have never been evaluated. In this study, phylogenetic relationships within Tordylium are investigated using parsimony analysis based on morphological data from 17 ingroup and 15 outgroup taxa from Turkey. The results indicate that Tordylium is paraphyletic due to the inclusion of Ormosciadium. Further, it suggests that Hasselquistia, Condylocarpus and Ainsworthia are nested within Tordylium, confirming their current taxonomic treatment as synonyms. Within the paraphyletic Tordylium, two major clades are apparent, but these clades are not compatible with the current sub‐generic classification. Tordylium lanatum, T. aegyptiacum and T. elegans, which have dimorphic mericarps, form a monophyletic subclade. In addition, it is suggested that T. aegaeum should be accepted as a distinct species rather than as a synonym of T. pestalozzae.  相似文献   
95.
Exercise training has been shown not only to influence physical fitness positively but also cognition in healthy and impaired populations. However, some particular exercise types, even though comparable based on physical efforts, have distinct cognitive and sensorimotor features. In this study, the effects of different types of exercise, such as fast ball sports and dance training, on brain electrical activity were investigated. Electroencephalography (EEG) scans were recorded in professional dancer, professional fast ball sports athlete (FBSA) and healthy control volunteer groups consisting of twelve subjects each. In FBSA, power of delta and theta frequency activities of EEG was significantly higher than those of the dancers and the controls. Conversely, dancers had significantly higher amplitudes in alpha and beta bands compared to FBSA and significantly higher amplitudes in the alpha band in comparison with controls. The results suggest that cognitive features of physical training can be reflected in resting brain electrical oscillations. The differences in resting brain electrical oscillations between the dancers and the FBSA can be the result of innate network differences determining the talents and/or plastic changes induced by physical training.  相似文献   
96.
Acanthocephaloides irregularis n. sp. (Arhythmacanthidae) is described from four species of marine fishes in the Gulf of Odessa and Sukhyi Lyman, Ukrainan Black Sea waters, making it the tenth species of the genus. The hosts are the combtooth blenny Parablennius zvonimiri (Kolombatovic) (Blenniidae), the mushroom goby Ponticola eurycephalus (Kessler) (Gobiidae), the tubenose goby Proterorhinus marmoratus (Pallas) (Gobiidae) and the black-striped pipefish Syngnathus abaster Risso (Syngnathidae). The new species is most similar to its closest relative, Acanthocephaloides propinquus (Dujardin, 1845), in proboscis shape and armature (12 longitudinal rows of 5 hooks) and the shape of the trunk, reproductive system and lemnisci, but differs in having randomly distributed trunk spines. These trunk spines are organised in circular rings of individual spines separated by aspinose zones. The new species is also unique in having an anterior trunk collar, a very large triangular cephalic ganglion, nucleated pouches at the posterior end of the proboscis receptacle, and hooks and spines with roots bearing anterior manubria. Valid and invalid species of Acanthocephaloides Meyer, 1932 are listed and a key to all ten species is included.  相似文献   
97.
High expression of Hsp27 in glioma cells has been closely associated with tumor cell proliferation and apoptosis inhibition. The aim of the present study was to asses the effects of rosmarinic acid (RA) on Hsp27 expression and apoptosis in non-transfected and transfected human U-87 MG cells. The effect of rosmarinic acid was compared to quercetin, which is known to be a good Hsp27 inhibitor. In order to block the expression of Hsp27 gene (HSPB1), transfection with specific siRNAs was performed. Western blotting technique was used to assess the Hsp27 expression, and caspase-3 colorimetric activity assay was performed to determine apoptosis induction. According to the results, it was found that RA and quercetin effectively silenced Hsp27 and both agents induced apoptosis by activating the caspase-3 pathway. Eighty and 215 μM RA decreased the level of Hsp27 by 28.8 and 46.7% and induced apoptosis by 30 and 54%, respectively. For the first time, we reported that rosmarinic acid has the ability to trigger caspase-3 induced apoptosis in human glioma cells. As a result of siRNA transfection, the Hsp27 gene was silenced by ~?50% but did not cause a statistically significant change in caspase-3 activation. It was also observed that apoptosis was induced at a higher level as a result of Hsp27 siRNA and subsequent quercetin or RA treatment. siRNA transfection and 215 μM RA treatment suppressed Hsp27 expression level by 90.5% and increased caspase-3 activity by 58%. Herein, we demonstrated that RA administered with siRNA seems to be a potent combination for glioblastoma therapy.  相似文献   
98.
Background: The activation and increased expression of BCR-ABL1 lead to malignant chronic myelogenous leukaemia (CML) cells, as well as the resistance to antitumour agents and apoptosis inducers. Moreover, TWIST-1 protein is a prognostic factor of leukemogenesis, and its level is raised in CML patients with cytogenetic resistance to imatinib. So, there is a likely relationship between BCR-ABL1 and TWIST-1 genes.

Objective: The aim of the study was to assess the relationship between TWIST-1 and BCR-ABL1 expressions.

Methods: Peripheral blood samples were obtained from 44 CML patients under treatment and also from ten healthy subjects as normal controls. The expression of TWIST-1 and BCR-ABL1 genes was measured using real-time PCR, and ABL1 was used as the reference gene. The gene expression was evaluated by REST software.

Results: The expression levels of TWIST-1 and BCR-ABL1 genes in CML patients was changed 40.23?±?177.75-fold and 6?±?18-fold, respectively.

Discussion: No significant relationship was observed between the expressions of TWIST-1 and BCR-ABL1 genes. All patients with TWIST-1 expression levels?≥100-fold had failure of response to treatment.

Conclusion: The probability of the relationship between BCR-ABL1 and TWIST-1 is still debatable, and the average of TWIST-1 expression has been higher in patients without response to treatment. Definitive conclusion needs further investigations.  相似文献   
99.
We have investigated defective steps in apoptosis that might account for the development of resistance. For this purpose, A549 and Calu1 NSCLC (non-small-cell lung cancer) cell lines were treated with cisplatin to obtain resistant sub-lines. Gene expression profiles and the phosphorylation status of the BAD (Bcl-2/Bcl-XL-antagonist, causing cell death) protein were determined for each cell line. Cell death and cytochrome c release were analysed after treating cell lines with their appropriate cisplatin doses. Gene expression of BAD, Bid, caspases 4 and 6 were clearly decreased in the resistant cell lines, and the differential phosphorylation status of BAD also seemed to play a role in the development of cisplatin resistance. Since this is a new cisplatin-resistant Calu1 cell line, it is noteworthy that DNA fragmentation, apoptotic cell ratio and cytochrome c levels were most decreased in the CR-Calu1 cell line.  相似文献   
100.
银鲴自然群体线粒体DNA的遗传分化   总被引:19,自引:0,他引:19  
运用21种限制性内切酶对银鲴自然群体进行了mtDNA的限制性片断长度多态性(RFLP)分析。发现银鲴自然群体存在丰富的mtDNA多态性,从4个群体39个个体中,共检测到12种单倍型,对这一现象的成成因进行了探讨。依据单倍型和群体的系统发育关系,结合地理分布的资料,对其现今分布区相互间的历史联系及其对银鲴起源和分化的影响进行了分析。  相似文献   
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