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81.
The lf (leucophore free) locus was previously reported autosomal recessive in the medaka fish (Oryzias latipes). However, extensive linkage analyses in this study using various strains revealed that the lf locus was closely sex-linked. The recombination frequency between lf and the male determining factor (y) was 2.2% (10 recombinants out of 464 progeny). Because the lf/lf homozygous fish do not have visible leucophores, they are distinguishable from wild type in early developmental stages. In the Qurt strain with heterozygous sex chromosomes (X(lf)/X(lf) in females and X(lf)/Y(+) in males), we can predict sex of each embryo on second day after fertilization. The strain should be a very useful material for studying sex determination or differentiation mechanisms in the medaka fish. 相似文献
82.
UV-irradiated plasmids (pNPV B and pBSCATSV) were transfected into RBCF-1 cells derived from a goldfish (Carassius auratus) and into a xeroderma pigmentosum (group A) cell line, XP20SSV. The frequency of stable neor transformation by pNPV B decreased in a dose-dependent manner. However, in spite of large differences in UV sensitivity detected in the colony formation assay, the dose-response curves of RBCF-1 cells and XP20SSV cells were almost the same. The photorecovery (PR) of transforming activity of UV-irradiated plasmids was confirmed in RBCF-1 cells but its extent was much smaller than that observed in the survival assay. The expression of the transfected cat (chloramphenicol acetyltransferase; CAT) gene after 24-h incubation in the dark was much more sensitive to UV irradiation when compared with the stable transformation assay. The extent of PR of cat gene expression in RBCF-1 cells was high and comparable with that of the survival assay. The CAT value of RBCF-1 cells transfected with UV-irradiated plasmids relative to that of unirradiated controls increased as incubation time in the dark after transfection became longer. This suggests that the UV lesions on the plasmids transfected in the RBCF-1 cells were repaired in the dark. The cat gene expression of UV-irradiated plasmids in XP20SSV was very low and independent of incubation time after transfection. 相似文献
83.
Larval dispersal can connect distant subpopulations, with important implications for marine population dynamics and persistence, biodiversity conservation and fisheries management. However, different dispersal pathways may affect the final phenotypes, and thus the performance and fitness of individuals that settle into subpopulations. Using otolith microchemical signatures that are indicative of ‘dispersive’ larvae (oceanic signatures) and ‘non-dispersive’ larvae (coastal signatures), we explore the population-level consequences of dispersal-induced variability in phenotypic mixtures for the common triplefin (a small reef fish). We evaluate lipid concentration and otolith microstructure and find that ‘non-dispersive’ larvae (i) have greater and less variable lipid reserves at settlement (and this variability attenuates at a slower rate), (ii) grow faster after settlement, and (iii) experience similar carry-over benefits of lipid reserves on post-settlement growth relative to ‘dispersive’ larvae. We then explore the consequences of phenotypic mixtures in a metapopulation model with two identical subpopulations replenished by variable contributions of ‘dispersive’ and ‘non-dispersive’ larvae and find that the resulting phenotypic mixtures can have profound effects on the size of the metapopulation. We show that, depending upon the patterns of connectivity, phenotypic mixtures can lead to larger metapopulations, suggesting dispersal-induced demographic heterogeneity may facilitate metapopulation persistence. 相似文献
84.
A Sequence Recall Task with disyllabic stimuli contrasting either for the location of prosodic prominence or for the medial consonant was administered to 150 subjects equally divided over five language groups. Scores showed a significant interaction between type of contrast and language group, such that groups did not differ on their performance on the consonant contrast, while two language groups, Dutch and Japanese, significantly outperformed the three other language groups (French, Indonesian and Persian) on the prosodic contrast. Since only Dutch and Japanese words have unpredictable stress or accent locations, the results are interpreted to mean that stress “deafness” is a property of speakers of languages without lexical stress or tone markings, as opposed to the presence of stress or accent contrasts in phrasal (post-lexical) constructions. Moreover, the degree of transparency between the locations of stress/tone and word boundaries did not appear to affect our results, despite earlier claims that this should have an effect. This finding is of significance for speech processing, language acquisition and phonological theory. 相似文献
85.
Shannon Bunker Joanna Holeniewska Sauparnika Vijay Annegret Dahlmann-Noor Peng Khaw Yin-Shan Ng David Shima Richard Foxton 《Journal of visualized experiments : JoVE》2015,(96)
Progress in understanding the pathophysiology, and providing novel treatments for glaucoma is dependent on good animal models of the disease. We present here a protocol for elevating intraocular pressure (IOP) in the rat, by injecting magnetic microspheres into the anterior chamber of the eye. The use of magnetic particles allows the user to manipulate the beads into the iridocorneal angle, thus providing a very effective blockade of fluid outflow from the trabecular meshwork. This leads to long-lasting IOP rises, and eventually neuronal death in the ganglion cell layer (GCL) as well as optic nerve pathology, as seen in patients with the disease. This method is simple to perform, as it does not require machinery, specialist surgical skills, or many hours of practice to perfect. Furthermore, the pressure elevations are very robust, and reinjection of the magnetic microspheres is not usually required unlike in some other models using plastic beads. Additionally, we believe this method is suitable for adaptation for the mouse eye. 相似文献
86.
Kimon Bekelis Symeon Missios Shannon Coy Redi Rahmani Robert J. Singer Todd A. MacKenzie 《PloS one》2015,10(9)
Object
Randomized trials have demonstrated a survival benefit for endovascular treatment of ruptured cerebral aneurysms. We investigated the association of surgical clipping and endovascular coiling with outcomes in subarachnoid hemorrhage (SAH) patients in a real-world regional cohort.Methods
We performed a cohort study involving patients with ruptured cerebral aneurysms, who underwent surgical clipping, or endovascular coiling from 2009–2013 and were registered in the Statewide Planning and Research Cooperative System (SPARCS) database. An instrumental variable analysis was used to investigate the association of treatment technique with outcomes.Results
Of the 4,098 patients undergoing treatment, 2,585 (63.1%) underwent coiling, and 1,513 (36.9%) underwent clipping. Using an instrumental variable analysis, we did not identify a difference in inpatient mortality [marginal effect (ME), -0.56; 95% CI, -1.03 to 0.02], length of stay (LOS) (ME, 1.72; 95% CI, -3.39 to 6.84), or the rate of 30-day readmissions (ME, -0.30; 95% CI, -0.82 to 0.22) between the two treatment techniques for patients with SAH. Clipping was associated with a higher rate of discharge to rehabilitation (ME, 0.63; 95% CI, 0.24 to 1.01). In sensitivity analysis, mixed effect regression, and propensity score adjusted regression models demonstrated identical results.Conclusions
Using a comprehensive all-payer cohort of patients in New York State presenting with aneurysmal SAH we did not identify an association of treatment method with mortality, LOS or 30-day readmission. Clipping was associated with a higher rate of discharge to rehabilitation. 相似文献87.
Ganesh Ram R. Visweswaran Shima Gholizadeh Marcel H. J. Ruiters Grietje Molema Robbert J. Kok Jan. A. A. M. Kamps 《PloS one》2015,10(9)
Together with mesangial cells, glomerular endothelial cells and the basement membrane, podocytes constitute the glomerular filtration barrier (GFB) of the kidney. Podocytes play a pivotal role in the progression of various kidney-related diseases such as glomerular sclerosis and glomerulonephritis that finally lead to chronic end-stage renal disease. During podocytopathies, the slit-diaphragm connecting the adjacent podocytes are detached leading to severe loss of proteins in the urine. The pathophysiology of podocytopathies makes podocytes a potential and challenging target for nanomedicine development, though there is a lack of known molecular targets for cell selective drug delivery. To identify VCAM-1 as a cell-surface receptor that is suitable for binding and internalization of nanomedicine carrier systems by podocytes, we investigated its expression in the immortalized podocyte cell lines AB8/13 and MPC-5, and in primary podocytes. Gene and protein expression analyses revealed that VCAM-1 expression is increased by podocytes upon TNFα-activation for up to 24 h. This was paralleled by anti-VCAM-1 antibody binding to the TNFα-activated cells, which can be employed as a ligand to facilitate the uptake of nanocarriers under inflammatory conditions. Hence, we next explored the possibilities of using VCAM-1 as a cell-surface receptor to deliver the potent immunosuppressant rapamycin to TNFα-activated podocytes using the lipid-based nanocarrier system Saint-O-Somes. Anti-VCAM-1-rapamycin-SAINT-O-Somes more effectively inhibited the cell migration of AB8/13 cells than free rapamycin and non-targeted rapamycin-SAINT-O-Somes indicating the potential of VCAM-1 targeted drug delivery to podocytes. 相似文献
88.
The presence of beta-endorphin-like immunoreactivity (beta-END-LI) in human gallbladder and its release were examined by means of radioimmunochemical measurements and immunohistochemical stainings. beta-END-LI was detected in the gallbladder (27.2 +/- 3.2 ng/g wet weight, mean +/- S.E.). The immunoreactivity in beta-END-LI extracted from the gallbladder was similar to that of synthetic beta-END, judging from the result of its inhibition curve parallel to that of the synthetic substance in the radioimmunoassay (RIA) system. On gel-filtration chromatography of a gallbladder extract, two components of beta-END-LI were found; one eluted on a position of beta-lipotropin (beta-LPH) and another on a position of synthetic beta-END. Specific beta-END-LI positive cells were detectable in metaplastic mucous glands. When human gallbladder mucosa was perfused with a solution of 10(-8) M or 10(-6) M cholecystokinin octapeptide (CCK-8), the release of beta-END-LI from mucosa into the perfusate increased 2-3 fold. These results indicate that beta-END-LI present in human gallbladder is released by the direct action of CCK-8 on the gallbladder mucosa and suggest that it may have a physiological or pathophysiological role. 相似文献
89.
Read JT Rahmani M Boroomand S Allahverdian S McManus BM Rennie PS 《The Journal of biological chemistry》2007,282(44):31954-31963
Versican, one of the key components of prostatic stroma, plays a central role in tumor initiation and progression. Here, we investigated promoter elements and mechanisms of androgen receptor (AR)-mediated regulation of the versican gene in prostate cancer cells. Using transient transfection assays in prostate cancer LNCaP and cervical cancer HeLa cells engineered to express the AR, we demonstrate that the synthetic androgen R1881 and dihydrotestosterone stimulate expression of a versican promoter-driven luciferase reporter vector (versican-Luc). Further, both basal and androgen-stimulated versican-Luc activities were significantly diminished in LNCaP cells, when AR gene expression was knocked down using a short hairpin RNA. Methylation-protection footprinting analysis revealed an AR-protected element between positions +75 and +102 of the proximal versican promoter, which strongly resembled a consensus steroid receptor element. Electrophoretic mobility shift and supershift assays revealed strong and specific binding of the recombinant AR DNA binding domain to oligonucleotides corresponding to this protected DNA sequence. Site-directed mutagenesis of the steroid receptor element site markedly diminished R1881-stimulated versican-Luc activity. In contrast to the response seen using LNCaP cells, R1881 did not significantly induce versican promoter activity and mRNA levels in AR-positive prostate stromal fibroblasts. Interestingly, overexpression of beta-catenin in the presence of androgen augmented versican promoter activity 10- and 30-fold and enhanced versican mRNA levels 2.8-fold in fibroblasts. In conclusion, we demonstrate that AR transactivates versican expression, which may augment tumor-stromal interactions and may contribute to prostate cancer progression. 相似文献
90.
The kinase inhibitor sorafenib induces cell death through a process involving induction of endoplasmic reticulum stress 总被引:1,自引:0,他引:1
Rahmani M Davis EM Crabtree TR Habibi JR Nguyen TK Dent P Grant S 《Molecular and cellular biology》2007,27(15):5499-5513
Sorafenib is a multikinase inhibitor that induces apoptosis in human leukemia and other malignant cells. Recently, we demonstrated that sorafenib diminishes Mcl-1 protein expression by inhibiting translation through a MEK1/2-ERK1/2 signaling-independent mechanism and that this phenomenon plays a key functional role in sorafenib-mediated lethality. Here, we report that inducible expression of constitutively active MEK1 fails to protect cells from sorafenib-mediated lethality, indicating that sorafenib-induced cell death is unrelated to MEK1/2-ERK1/2 pathway inactivation. Notably, treatment with sorafenib induced endoplasmic reticulum (ER) stress in human leukemia cells (U937) manifested by immediate cytosolic-calcium mobilization, GADD153 and GADD34 protein induction, PKR-like ER kinase (PERK) and eukaryotic initiation factor 2alpha (eIF2alpha) phosphorylation, XBP1 splicing, and a general reduction in protein synthesis as assessed by [35S]methionine incorporation. These events were accompanied by pronounced generation of reactive oxygen species through a mechanism dependent upon cytosolic-calcium mobilization and a significant decline in GRP78/Bip protein levels. Interestingly, enforced expression of IRE1alpha markedly reduced sorafenib-mediated apoptosis, whereas knockdown of IRE1alpha or XBP1, disruption of PERK activity, or inhibition of eIF2alpha phosphorylation enhanced sorafenib-mediated lethality. Finally, downregulation of caspase-2 or caspase-4 by small interfering RNA significantly diminished apoptosis induced by sorafenib. Together, these findings demonstrate that ER stress represents a central component of a MEK1/2-ERK1/2-independent cell death program triggered by sorafenib. 相似文献