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81.
Junyu Liu Michael Maxwell Thom Cuddihy Theo Crawford Madeline Bassetti Cameron Hyde Steve Peigneur Jan Tytgat Eivind A. B. Undheim Mehdi Mobli 《Protein science : a publication of the Protein Society》2023,32(2)
Receptor avidity through multivalency is a highly sought‐after property of ligands. While readily available in nature in the form of bivalent antibodies, this property remains challenging to engineer in synthetic molecules. The discovery of several bivalent venom peptides containing two homologous and independently folded domains (in a tandem repeat arrangement) has provided a unique opportunity to better understand the underpinning design of multivalency in multimeric biomolecules, as well as how naturally occurring multivalent ligands can be identified. In previous work, we classified these molecules as a larger class termed secreted cysteine‐rich repeat‐proteins (SCREPs). Here, we present an online resource; ScrepYard, designed to assist researchers in identification of SCREP sequences of interest and to aid in characterizing this emerging class of biomolecules. Analysis of sequences within the ScrepYard reveals that two‐domain tandem repeats constitute the most abundant SCREP domain architecture, while the interdomain “linker” regions connecting the functional domains are found to be abundant in amino acids with short or polar sidechains and contain an unusually high abundance of proline residues. Finally, we demonstrate the utility of ScrepYard as a virtual screening tool for discovery of putatively multivalent peptides, by using it as a resource to identify a previously uncharacterized serine protease inhibitor and confirm its predicted activity using an enzyme assay. 相似文献
82.
Phloridzin reduces blood glucose levels and improves lipids metabolism in streptozotocin-induced diabetic rats 总被引:2,自引:0,他引:2
Najafian M Jahromi MZ Nowroznejhad MJ Khajeaian P Kargar MM Sadeghi M Arasteh A 《Molecular biology reports》2012,39(5):5299-5306
Phloridzin is the specific and competitive inhibition of sodium/glucose cotransporters in the intestine (SGLT1) and kidney
(SGLT2). This property which could be useful in the management of postprandial hyperglycemia in diabetes and related disorders.
Phloridzin is one of the dihydrochalcones typically contained in apples and in apple-derived products. The effect of phloridzin
orally doses 5, 10, 20 and 40 mg/kg body weight on diabetes was tested in a streptozotocin-induced rat model of diabetes type
1. From beneficial effect of this compound is significant reduction of blood glucose levels and improve dyslipidemia in diabetic
rats. As a well-known consequence of becoming diabetic, urine volume and water intake were significantly increased. Administration
of phloridzin reduced urine volume and water intake in a dose-dependent manner. Phloretin decreases of food consumption, as
well as a marked lowering in the weight. In conclusion, this compound could be proposed as an antihyperglycemic and antihyperlipidemic
agent in diabetes and potential therapeutic in obesity. 相似文献
83.
Ivan Light Georges Sabagh Mehdi Bozorgmehr Claudia Der‐Martirosian 《Ethnic and racial studies》2013,36(4):581-597
Internal ethnicity refers to ethnic subgroups within an immigrant group. An ‘ethnic economy’ includes the self‐employed and their co‐ethnic workers. Although most research treats the boundaries of ‘ethnic economy’ and its variant, the ‘ethnic enclave economy’, as though they were coterminous with those of national‐origin immigrant groups, this assumption is unreliable. Ethnic boundaries need not coincide with those of nationality origin when internal ethnicity exists. To test this hypothesis, we utilize survey data collected from a sample of Iranians in Los Angeles. Because this national‐origin immigrant group contains four ethno‐religious subgroups (Armenians, Bahais, Jews and Muslims), the Iranians in Los Angeles operated four distinctive ethnic economies, not one. Each ethno‐religious subgroup had its own ethnic economy, and these separate economies were only weakly tied to an encompassing Iranian ethnic economy. 相似文献
84.
85.
Bahareh Majnon Jahromi Mehdi Gheibi Christian Kehlmaier Shahram Hesami 《Zoology in the Middle East.》2017,63(4):336-347
A checklist of 39 species of the genus Tomosvaryella Aczél (Diptera, Pipunculidae) known from the Middle East is provided. A new species, T. hamata Majnon Jahromi &; Kehlmaier sp. n. is described from southern Iran and diagnostic characters of male and female terminalia are illustrated. Tomosvaryella dentiterebra (Collin, 1949) is redescribed and male and female terminalia are illustrated for the first time. A phylogenetic maximum-likelihood analysis and uncorrected pairwise genetic distances of 18 out of 22 Iranian species of Tomosvaryella based on DNA barcodes of the mitochondrial COI gene are presented and also discussed.http://www.zoobank.org/urn:lsid:zoobank.org:pub:FF8C116D-0C92-431A-B52C-11F3711B6A62 相似文献
86.
Kheirandish Maryam Siadat Seyed Davar Norouzian Dariush Razavi Mohamad Reza Aghasadeghi Mohammad Reza Rezaei Nima Farazmand Ali Izadi Mobarakeh Jalal Zangeneh Mehrangiz Moshiri Arfa Sadat Seyed Mehdi Salmani Ali Sharifat 《Annals of microbiology》2009,59(4):801-806
Neisseria meningitidis is efficiently phagocytosed by polymorphonuclear leukocytes (PMNS) following opsonization with opsonic antibodies; opsonophagocytosis is the primary mechanism for clearance of meningococci from the host. Thus, in testing meningococcal vaccines, the level of opsonophagocytic antibodies appears to correlate with vaccine-induced protection. Our previous studies demonstrated that the conjugation ofN. meningitidis serogroup A capsular polysaccharide (CPSA) to serogroup B outer membrane vesicle (OMV) could induce a high level of bactericidal antibody response against serogroup A meningococci in animals. The purpose of this study was to evaluate opsonophagocytic activity of the conjugate of CPSA to OMV (CPSA-OMV). In order to evaluate the potential efficacy of CPSA-OMV a flow cytometric opsonophagocytic assay was used. The conjugate and controls were injected intramuscularly into four groups of rabbits with boosters on days 14, 28 and 42 following primary immunization. The rabbits were bled prior to injection and two weeks after each injection. Opsonophagocytic activity of antibodies in hyperimmune sera through rabbit PMNS were measured with flow cytometer, using dihydrorhodamine-123 as a probe. The results indicated that our conjugate could induce a highly significant level of opsonophagocytic activity against serogroup A meningococci after 56 days compared to the control groups (P<0.05). We conclude that this conjugate represents a vaccine candidate against serogroups A and B meningococci after further investigation. 相似文献
87.
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90.
Shahid S Abid A Mehdi SQ Mehdi QS Firasat S Lanewala A Naqvi SA Naqvi AA Rizvi SA Rizvi AU Khaliq S 《Gene》2012,493(1):165-168
Nephrotic syndrome is a common pediatric glomerular disease associated with heavy proteinuria. Since, the angiotensin converting enzyme (ACE) gene insertion/deletion (I/D) polymorphism is a putative genetic risk factor for NS, in this study, ACE (I/D) polymorphism was analyzed in 268 NS and 223 control samples by a PCR-based method. The genotypic and allelic frequencies were determined and the association between ACE I/D polymorphism and NS was evaluated. The frequency distribution of the II, ID and DD genotypes was 82 (30.6%), 128 (47.8%) and 58 (21.6%) in the NS patients and 9 (4.0%), 171 (76.7%) and 43 (19.3%) in the control samples respectively. In the Pakistani pediatric NS population, the II genotypic and allelic frequencies were found to be significantly associated with the disease (OR = 6.755; C.I = 3-14.9). No significant association was found between this polymorphism and the response to standard steroid therapy. Thus, in contrast to reports from other parts of the world, the II genotype was found to be significantly associated with NS in the Indian and Malay populations and in the Pakistani population described here. To our knowledge, this is the first report from Pakistan describing the association of the ACE I/D polymorphism with pediatric NS. On the basis of these results, it is suggested that analysis of the ACE (I/D) polymorphism should be performed for the early diagnosis in the high risk NS patients in South Asia. 相似文献