42 research outputs found
Implications of MicroRNAs in the Vascular Homeostasis and Remodeling
Vascular remodeling or arterial remodeling is a process of adaptive alteration of vascular wall architecture and leads to the endothelial cell (EC) dysfunction and synthetic or contractile phenotypic change of VSMCs, and the infiltration of monocytes and Macrophages that promotes vascular diseases including atherosclerosis. Recent findings have demonstrated that microRNAs (miRNAs) are involved in regulating gene expression at posttranscriptional level and disease pathogenesis. A change of miRNA expression profiles plays key roles in the gene expressions and the regulation of cellular functions. In this chapter, we summarize the vascular remodeling-related miRNAs and their functions in vascular biology
Large Cell Neuroendocrine Carcinoma of the Cervix with Sequential Metastasis to Different Sites: A Case Report
Neuroendocrine carcinoma of the cervix is rare, and prognosis is very poor. Because of its rarity, effective treatment of neuroendocrine carcinoma of the cervix has not been established. It has distinct patterns of metastasis, but can be successfully treated with radical surgery and platinum-based chemotherapy. We report a 50-year-old woman who was diagnosed with large cell neuroendocrine carcinoma of the cervix and underwent radical surgery followed by adjuvant chemoradiation therapy. She experienced recurrence several times and to different sites, with sequential metastasis to the lung, breast, and retroperitoneum, but nevertheless survived more than 5 years
The immediate upstream region of the 5 0 -UTR from the AUG start codon has a pronounced effect on the translational efficiency in Arabidopsis thaliana
ABSTRACT The nucleotide sequence around the translational initiation site is an important cis-acting element for post-transcriptional regulation. However, it has not been fully understood how the sequence context at the 5 0 -untranslated region (5 0 -UTR) affects the translational efficiency of individual mRNAs. In this study, we provide evidence that the 5 0 -UTRs of Arabidopsis genes showing a great difference in the nucleotide sequence vary greatly in translational efficiency with more than a 200-fold difference. Of the four types of nucleotides, the A residue was the most favourable nucleotide from positions À1 to À21 of the 5 0 -UTRs in Arabidopsis genes. In particular, the A residue in the 5 0 -UTR from positions À1 to À5 was required for a high-level translational efficiency. In contrast, the T residue in the 5 0 -UTR from positions À1 to À5 was the least favourable nucleotide in translational efficiency. Furthermore, the effect of the sequence context in the À1 to À21 region of the 5 0 -UTR was conserved in different plant species. Based on these observations, we propose that the sequence context immediately upstream of the AUG initiation codon plays a crucial role in determining the translational efficiency of plant genes
Les déterminants des performances scolaires des élèves marocains
Le Maroc fait partie des pays en développement dont le niveau des acquis des élèves reste relativement faible. En dépit des efforts engagés en vue d’améliorer en partie la qualité des apprentissages, les résultats des enquêtes internationales et nationales révèlent de faibles niveaux des acquis. Dès lors, l’objectif de cet article est de revenir sur les facteurs qui influencent les performances scolaires des élèves. Nous nous intéressons plus spécifiquement aux déterminants microéconomiques de la qualité de l’éducation à travers les performances des élèves. Les études sur les déterminants des performances scolaires sont riches d’enseignement. Les premières contributions se sont focalisées sur le rôle de l’environnement familial dans l’explication de la réussite des élèves (Coleman, 1966, par exemple). D’autres, plus récemment, ont abordé les facteurs liés à l’établissement scolaire. Pour autant, les contributions récentes mettent en avant l’importance à la fois de l’environnement familial et de l’école (Hanushek, 2003). Des travaux plus récents oulignent également l’influence des pairs sur les performances scolaires. Le présent travail s’inscrit dans cette logique. Son originalité se situe à un double niveau. La première réside dans la mise en évidence de l’ensemble des facteurs explicatifs des performances des élèves et des inégalités scolaires. Malgré l’existence d’une littérature abondante sur le sujet, cette question n’a pas été abordée, à notre connaissance, dans le cas marocain. La seconde cherche à corriger les problèmes d’endogénéité dans les modèles multiniveaux. Enfin, La technique d’imputation adoptée permet de traiter de façon pertinente les valeurs manquantes dans les bases de données. Cet article est structuré en trois parties. La première aborde la littérature empirique sur les déterminants de la réussite scolaire des élèves. La deuxième partie examine le modèle utilisé et décrit la base de données du Programme national d’évaluation des acquis (PNEA). Elle examine l’approche et la méthodologie utilisée. Enfin, la troisième partie traite des résultats obtenus et nous permet de formuler les principaux enseignements pouvant être tirés de nos résultats en matière de politiques publiques
Enzyme engineering of bovine trypsin
Bovine trypsin is a biocatalyst widely used to cleave recombinant proteins during the downstream processing of therapeutic proteins, and is used particularly for insulin bioprocessing. Evolution has produced a wealth of natural biocatalysts over billions of years, which are generally not optimised for specific industrial applications. Bovine trypsin has a relatively broad specificity towards cleavage at the C-terminal end of arginine or lysine residues. Consequently it has a tendency to cleave alternative sites in the insulin process leading to loss of yield and more complex downstream processing. This project describes efforts to alter the primary specificity of bovine trypsin. Trypsin variants were generated using two traditional random mutagenesis methods tailored to improve the chance of producing a useful mutant. These were focussed error prone PCR (fepPCR) and multiple-site saturation mutagenesis (MSSM). In order to select residues useful for MSSM, a study of the correlation between (1) mutations enhancing specificity or activity and (2) sequence entropy and distance of mutations from the active site was carried out based on past examples of directed and rational evolution. This analysis along with biochemical information for trypsin aided the selection of two specificity "hotspots" for random mutagenesis, each comprising four residues. These hotspots were regions in the trypsin gene close to or directly involved in substrate binding. Depending on the mutagenesis method used, the size of the mutant libraries differed considerably. For example, fepPCR of a 522 bp region of the trypsin gene required approximately 3,000 mutants to encompass all possibilities whereas the library size for MSSM was 160,000 for each of the selected four-residue regions. Two alternative library screening approaches, with different throughput capabilities, were tested to isolate mutants of interest. Automated colony screening was considered suitable for the smaller fepPCR library and consisted of the following steps: (1) transformation of a plasmid library into E. coli BL21-Gold(DE3) cells (2) fermentation of individual colonies in 384 square-well microplates (3) lysis of the cultures and (4) spectrophotometric activity measurement on a variety of substrates. The best mutant had a 2.54-fold improvement in arginine specificity. For the larger MSSM libraries, a nutritional selection method was developed using E. coli arg-auxotrophic strains. An alternative approach to generating trypsin variants was also explored based on the known ability of bovine trypsin to autolyse into "pseudo-trypsins". Since these pseudo-trypsins are variants of the native form of the enzyme, it was anticipated that they would have specificities different to that of the native enzyme. Efforts were made to separate the variants via novel chromatographic techniques and to characterise them with respect to molecular weight and specificity. Finally, the activity profile of bovine trypsin was comprehensively carried out on a range of novel substrates, and a comparison made between commercially available bovine trypsin and Eli Lilly's recombinant trypsin. Similar reaction profiles were returned by both enzymes on all substrates with the previously unreported finding that there was a preference for cleavage at the C-terminal end of two positively charged basic residues (i.e. KR or RR rather than GR)
Huge Ovarian Tumor: An Unusual Presentation of Gastric-Type Endocervical Adenocarcinoma
Gastric endocervical adenocarcinoma is a rare type of cervical cancer. It was recently classified as a subtype of cervical cancer that exhibits an aggressive behavior with poor prognosis compared to other cancer types. Nevertheless, little is known about the clinical behavior of this cervical cancer subtype to establish a definitive treatment protocol. Herein, we report a case of poorly advanced gastric endocervical adenocarcinoma in a 47-year-old Korean woman who was suspected to have a borderline ovarian tumor and underwent a laparotomy. A gastric-type endocervical adenocarcinoma was diagnosed incidentally on histopathological examination
Primary Ovarian Neuroendocrine Carcinoid Tumor Arising in a Mature Cystic Teratoma
Primary ovarian neuroendocrine carcinoid tumors are extremely rare. However, their clinical course is good, and hence, fertility-sparing surgery is a feasible treatment option in cases of unilateral localized lesions. In this report, we present the case of a 20-year-old nulliparous woman who was diagnosed as having a primary ovarian neuroendocrine carcinoid tumor arising from a mature cystic teratoma. She underwent laparoscopic right ovarian cystectomy, and her postoperative recovery was uneventful. The patient has been under close observation over a 1-year follow-up period and has shown no evidence of tumor recurrence
An overload-resilient flow removal algorithm for M-LWDF scheduler
In the real-time multimedia applications, packet delay should meet stringent Quality of Service (QoS) requirements. Delay Earliest Due Date (EDD) scheduler, originally designed for wireline data networks to operate under a maximum allowed delay, cannot be directly applied to wireless networks, due to the location-dependent errors and time-varying channel conditions. Several modifications of EDD scheduler have been proposed for wireless applications, which typically assume successful admission control, a condition hard to satisfy with wireless networks. In this paper, we propose a removal algorithm for downlink scheduler designed to perform under overloaded situations. Simulation results show that our proposed algorithm outperforms the conventional ones in the QoS guaranteed flows