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31.
Recovery from acute renal failure (ARF) requires the replacement of injured cells by new cells that are able to restore tubule epithelial integrity. We have recently described the expression of nephrogenic proteins [Vimentin, neural cell adhesion molecule, basic fibroblast growth factor (bFGF), Pax-2, bone morphogen protein-7, Noggin, Smad 1-5-8, p-Smad, hypoxia-inducible factor-1alpha, vascular endothelial growth factor], in a time frame similar to that observed in kidney development, after ischemic ARF induced in an ischemia-reperfusion (I/R) model. Furthermore, we show that bFGF, a morphogen involved in mesenchyme/epithelial transition in kidney development, induces a reexpression of morphogenic proteins in an earlier time frame and accelerates the recovery process after renal damage. Herein, we confirm that renal morphogenes are modulated by bFGF and hypothesized that a decrease in bFGF receptor 2 (bFGFR2) levels by the use of antisense oligonucleotides diminishes the expression of morphogenes. Male Sprague-Dawley rats submitted to ischemic injury were injected with 112 microg/kg bFGFR2 antisense oligonucleotide (bFGFR2-ASO) followed by reperfusion. Rats were killed, and the expression of nephrogenic proteins and renal marker damage was analyzed by immunohistochemistry and immunoblot. Animals subjected to I/R treated with bFGFR2-ASO showed a significant reduction in morphogen levels (P < 0.05). In addition, we observed an increase in markers of renal damage: macrophages (ED-1) and interstitial alpha-smooth muscle actin. These results confirm that bFGF participates in the recovery process and that treatment with bFGFR2-ASO induces an altered expression of morphogen proteins.  相似文献   
32.
Recent investigations identified heterozygous CFC1 mutations in subjects with heterotaxy syndrome, all of whom had congenital cardiac malformations, including malposition of the great arteries. We hypothesized that a subset of patients with similar types of congenital heart disease---namely, transposition of the great arteries and double-outlet right ventricle, in the absence of laterality defects---would also have CFC1 mutations. Our analysis of the CFC1 gene in patients with these cardiac disorders identified two disease-related mutations in 86 patients. The present study identifies the first autosomal single-gene defect for these cardiac malformations and indicates that some cases of transposition of the great arteries and double-outlet right ventricle can share a common genetic etiology with heterotaxy syndrome. In addition, these results demonstrate that the molecular pathway involving CFC1 plays a critical role in normal and abnormal cardiovascular development.  相似文献   
33.
The armyworm, Spodoptera frugiperda, is the principal pest of corn in Brazil. Control is achieved primarily by synthetic insecticides, which cause problems for the agro-ecosystem. Alternative methods of control are under investigation and citronella (Cymbopogon winterianus) essential oil appears to be a promising agent. We investigated the effects of citronella oil using histological, histochemical and immunohistochemical methods. The midgut of larvae treated with citronella exhibited altered epithelium including cytoplasmic protrusions, columnar cell extrusion, pyknotic nuclei, and increased periodic acid-Schiff positive granules. Regenerative cells in the epithelium of the midgut increased in number, which facilitated subsequent regeneration of this tissue. After exposure to citronella, trophocytes, the principal cell type of the fat body, possessed enlarged vacuoles and mitotic bodies, and contained reduced amounts of glycogen, lipid, and protein. Citronella oil caused morphological changes of the midgut and reduction of stored resources in the fat body, which may adversely affect insect reproduction and survival.  相似文献   
34.
ABSTRACT

Sleep deprivation impairs performance on cognitive tasks, but it is unclear which cognitive processes it degrades. We administered a semantic matching task with variable stimulus onset asynchrony (SOA) and both speeded and self-paced trial blocks. The task was administered at the baseline and 24 hours later after 30.8 hours of total sleep deprivation (TSD) or matching well-rested control. After sleep deprivation, the 20% slowest response times (RTs) were significantly increased. However, the semantic encoding time component of the RTs remained at baseline level. Thus, the performance impairment induced by sleep deprivation on this task occurred in cognitive processes downstream of semantic encoding.  相似文献   
35.
Holoprosencephaly (HPE) is a genetically heterogeneous disorder that affects the midline development of the forebrain and midface in humans. As a step toward identifying one of the HPE genes, we have set out to refine the HPE3 critical region on human chromosome 7q36 by analyzing 34 cell lines from families with cytogenetic abnormalities involving 7q, 24 of which are associated with HPE. Genomic clones surrounding the DNA marker D7S104, which has previously been shown to be in the HPE3 critical region, have been examined by fluorescent in situ hybridization and microsatellite analysis of our panel of patient cell lines. We report the analysis of a cluster of four translocation breakpoints within a 300-kb region of 7q36 that serves to define the minimal critical region for HPE3 and that has directed the search for candidate genes. The human Sonic Hedgehog (hSHH) gene maps to this region and has been shown to be HPE3 on the basis of mutations within the coding region of the gene. We present evidence that cytogenetic deletions and/or rearrangements of this region of chromosome 7q containing Sonic Hedgehog, and translocations that may suppress Sonic Hedgehog gene expression through a position effect are common mechanisms leading to HPE. Received: 23 December 1996 / Accepted: 17 March 1997  相似文献   
36.
Focusing on the interactional aspects of art in health interventions, we qualify guidelines for art in hospitals. Patients in this user-oriented study primarily ranked items to favor figurative art painted in light colors; however both figurative and abstract art in light and dark colors figured among the highest ratings. The role of spatial context, motif, color and shapes seems to have an effect on patients’ experience of a hospital stay. This article draws attention to the application of visual art as a source of stimulus and healing—and a means to affect patient satisfaction in hospitals.  相似文献   
37.
Trade in freshwater ornamental fish in South Africa is currently regulated by a ‘blacklist’ to prevent potentially invasive taxa from establishing in the country. Because its effective implementation requires accurate identification, the aim of the present study was to test whether DNA barcoding is a useful tool to identify freshwater fishes in the South African pet trade. A total of 351 aquarium fish specimens, representing 185 traded taxa, were sequenced for the mitochondrial COI barcoding marker in 2011 and 2012. Lake Malawi cichlids were treated as a single group due to a lack of resolution in their COI marker, resulting in a data set of 137 successfully sequenced taxa. The Barcode Of Life Database (BOLD) and GenBank were used for taxonomic assignment comparisons. The genetic identification matched the scientific name inferred from the trade name for 60 taxa (43.8%) using BOLD, and for 67 taxa (48.9%) using GenBank. A genetic ID could not be assigned in 47 (34.3%) cases using BOLD and in 37 cases (27%) using GenBank. Whereas DNA barcoding can be a useful tool to help identify imported freshwater fishes, it requires further development of publicly available databases to become a reliable means of identification.  相似文献   
38.
Background Common marmoset monkeys (Callithrix jacchus) are readily used in biomedical research. However, superovulation for embryonic stem cell production and developmental research still remain difficult. Inexplicably, follicle‐stimulating hormone (FSH) as key player in superovulation has to be administered in extremely high dosages in this non‐human primate compared to human. Methods To evaluate whether marmoset FSH (cjFSH) is functionally more competent than its human homologue on the marmoset FSH receptor (cjFSHR), we established in vitro a homologous system characterizing homologous and recombinantly produced cjFSH. Results Upon stimulation of two cell lines stably expressing either the marmoset or the human FSH receptor (cj/hFSHR), respectively, the second messenger signaling of the activated receptor displayed no significant difference in ED50 values. Thermostability of cjFSH was significantly prolonged by roughly 20% on both FSHRs. Conclusion High FSH dosage in marmoset superovulation cannot be explained by enhanced biopotency of the natural animal’s gonadotropin.  相似文献   
39.
苯肼对红细胞在体衰老过程中微观流变特性的影响   总被引:2,自引:1,他引:2  
在Brunara等人用苯肼使动物造成急性溶血性贫血的方法基础上,建立一种由急性溶血性贫血后,而诱发家兔幼红细胞增多的非正常生理状态的红细胞在体衰老模型,继而研究新生红细胞从产生到死亡死亡过程,即衰老过程的流变学特性的变化规律。通过对新生红细胞的压积、变形、取向及与之相应的全血的粘度、血沉等指标的连续60多天的监测,发现红细胞在衰老过程中的微观流变学特性确实有明显改变。红细胞在体衰老过程中微观流变特性逐渐变差。  相似文献   
40.
华西银腊梅挥发油化学成分的研究   总被引:1,自引:0,他引:1  
用水蒸气蒸馏法提取华西银腊梅挥发油,并用气相色谱-质谱(GC-MS)联用技术对其挥发油的化学成分进行分析,结果共鉴定了其中的39种成分,所鉴定成分含量约占总检出量的87.83%。其化学成分主要为(Z,Z)-9,12-十八碳二烯酸甲酯(9.00%),壬醛(5.83%),二十一烷(5.69%),二十烷(5.08%),辛炔酸(4.50%),2,6,10,15-四甲基十七烷(3.93%),(Z)-6-十八烯酸甲酯(3.65%),3,8-二甲基十一烷(3.52%),1-十六碳炔(3.31%),肉豆蔻酸(2.86%),月桂醛(2.81%),壬酸(2.23%),5,6,7,7α-四氢-4,4,7α三甲基-2(4H)-苯并呋喃酮(2.18%)等。  相似文献   
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