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101.
Kotkar HM  Bhide AJ  Gupta VS  Giri AP 《Gene》2012,496(1):1-7
Venoms contain highly complex mixtures that typically include hundreds of different components and have evolved independently in a diverse range of animals including platypuses, shrews, snakes, lizards, fishes, echinoderms, spiders, wasps, centipedes, sea snails, cephalopods, jellyfish and sea anemones. Many venom genes evolved through gene duplication. Gene duplication occurs in all domains of life and provides the raw substrate from which novel function arise. In this review, we focus on the role that gene duplication has played in the origin and diversification of venom genes. We outline the selective advantages of venom gene duplicates and the role that selection has played in the retention of these duplicates. We use toxin gene intermediates to help trace the evolution of toxin innovation. We also focus on other genomic processes, such as exon and domain duplications, in venom evolution. Finally, we conclude by focusing on the use of high throughput sequencing technology in understanding venom evolution.  相似文献   
102.
Bio-nanocapsules (BNCs) are hollow nanoparticles composed of the L protein of hepatitis B virus (HBV) surface antigen (HBsAg), which can specifically introduce genes and drugs into various kinds of target cells. Although the classic electroporation method has typically been used to introduce highly charged molecules such as DNA, it is rarely adopted for proteins due to its very low efficiency. In this study, a novel approach to the preparation of BNC was established whereby a target protein was pre-encapsulated during the course of nanoparticle formation. Briefly, because of the process of BNC formation in a budding manner on the endoplasmic reticulum (ER) membrane, the association of target proteins to the ER membrane with lipidation sequences (ER membrane localization sequences) could directly generate protein-encapsulating BNC in collaboration with co-expression of the L proteins. Since the membrane-localized proteins are automatically enveloped into BNCs during the budding event, this method can be protect the proteins and BNCs from damage caused by electroporation and obviate the need for laborious consideration to study the optimal conditions for protein encapsulation. This approach would be a useful method for encapsulating therapeutic candidate proteins into BNCs.  相似文献   
103.
Huang Y  Yin H  Wang J  Ma X  Zhang Y  Chen K 《Gene》2012,504(2):284-287
Our previous studies suggest that Fc receptor III A of immunoglobulin G (FcγRIIIA, also named CD16) is closely correlated to coronary heart disease (CHD). However, whether or not deregulated FcγRIIIA expression is involved in the development of CHD remains largely unclear. Herein, we investigated the FcγRIIIA mRNA expression in the leukocytes, the serum protein level of soluble CD16 (sCD16) and membrane CD16 on monocytes from 100 diagnosed CHD patients and 40 healthy individuals. Our results demonstrated that there was a significant increase of FcγRIIIA at the mRNA level in leukocytes, and at the protein level for both sCD16 in sera and membrane CD16 on monocytes from CHD patients compared to the healthy control. Similarly to the soluble CD14 (sCD14), the level of macrophage colony stimulating factor (M-CSF) in sera was also higher in CHD patients than that in the control individuals. Furthermore, the levels of inflammatory cytokines, such as tumor necrosis factor-alpha (TNF-α) and interleukin-1 (IL-1), in sera and the mean fluorescent intensity of intercellular adhesion molecule 1 (ICAM-1, CD54) on CD14(+) CD16(+) monocytes were increased in CHD patients. Overall, these data demonstrated that FcγRIIIA (CD16) is involved in the pathogenesis of CHD by activating monocytes and stimulating inflammation. The significant increase of CD14(+) CD16(+) monocytes in CHD patients therefore suggested that the increase of the FcγRIIIA level might be a sensitive marker for the CHD diagnosis.  相似文献   
104.
Non-specific lipid transfer proteins belonging to LTP1 family represent the most important allergens for non pollen-related allergies to Rosaceae fruits in the Mediterranean area. Peach LTP1 (Pru p 3) is a major allergen and is considered the prototypic allergenic LTP. On the contrary, pear allergy without pollinosis seems to be under-reported when compared to other Rosaceae fruits suggesting that the as-yet-uncharacterized pear LTP1 (Pyr c 3) has in vivo a low allergenicity. We report here on the identification of four cDNAs encoding for LTP1 in pear fruits. The two isoforms exhibiting amino acid sequences most similar to those of peach and apple homologues were obtained as recombinant proteins. Such isoforms exhibited CD spectra and lipid binding ability typical of LTP1 family. Moreover, pear LTP1 mRNA was mainly found in the peel, as previously shown for other Rosaceae fruits. By means of IgE ELISA assays a considerable immunoreactivity of these proteins to LTP-sensitive patient sera was detected, even though allergic reactions after ingestion of pear were not reported in the clinical history of the patients. Finally, the abundance of LTP1 in protein extracts from pear peel, in which LTP1 from Rosaceae fruits is mainly confined, was estimated to be much lower as compared to peach peel. Our data suggest that the two isoforms of pear LTP1 characterized in this study possess biochemical features and IgE-binding ability similar to allergenic LTPs. Their low concentrations in pear might be the cause of the low frequency of LTP-mediated pear allergy.  相似文献   
105.

Background

Autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy syndrome (APECED) is an autosomal recessive disease due to mutations of the autoimmune regulator (AIRE) gene. Typical manifestations include candidiasis, Addison's disease, and hypoparathyroidism. Type 1 diabetes, alopecia, vitiligo, ectodermal dystrophy, celiac disease and other intestinal dysfunctions, chronic atrophic gastritis, chronic active hepatitis, autoimmune thyroid disorders, pernicious anemia and premature ovarian failure are other rare associated diseases although other conditions have been associated with APECED.

Case presentation

What follows is the clinical, endocrinological and molecular data of a female APECED patient coming from Lithuania. The patient was affected by chronic mucocutaneous candidiasis, hypoparathyroidism and pre-clinical Addison's disease. Using direct sequencing of all the 14 exons of the AIRE gene in the patient's DNA, we identified in exon 6 the known mutation c.769 C>T (p.Arg257X) in compound heterozygosity with the newly discovered mutation c.1214delC (p.Pro405fs) in exon 10. The novel mutation results in a frameshift that is predicted to alter the sequence of the protein starting from amino acid 405 as well as to cause its premature truncation, therefore a non-functional Aire protein.

Conclusions

A novel mutation has been described in a patient with APECED with classical clinical components, found in compound heterozygosity with the c.769 C>T variation. Expanded epidemiological investigations based on AIRE gene sequencing are necessary to verify the relevancy of the novel mutation to APECED etiopathogenesis in the Lithuanian population and to prove its diagnostic efficacy in association with clinical and immunological findings.  相似文献   
106.
Knowledge of what constitute normal serum immunoglobulin (Ig) concentrations are important for the diagnosis of immunologic disorders. Data on normal Ig evaluated by nephelometry are limited in healthy Asian children, none being available for Thai children. One hundred and forty-eight healthy Thai children aged 2-15 years were tested for serum immunoglobulins G, A, M, G1, G2, G3, and G4 (Ig G, A, M, G1, G2, G3, and G4) by nephelometry. Sixty-three percent were girls of median interquartile range age 6.9 (4.8-9.7) years. The geometric means for each Ig were summarized and categorized by age. Statistical analyses were used to compare Igs between sexes and age groups, and to compare IgG in this study with data from other published studies. The average ratios of IgG subclasses/IgG for Ig G1:2:3:4 were 66:22:5:7%. IgG, IgA, IgG2, and IgG3 concentrations showed a gradual increase with increasing age. There were no significant sex differences for any immunoglobulin isotype (P= 0.971). Our mean IgG concentration was lower than that measured by the radial diffusion method in healthy Thai children (P < 0.05). In all age groups, the mean IgG concentration in our study was significantly higher than that reported in Turkish and USA children, evaluated by the nephelometric and radial diffusion techniques, respectively (both P < 0.001). This study provides information about normal Ig concentrations measured by nephelometry in healthy Asian children and illustrates the importance of ascertaining normal Ig values for age- and ethnic-matched controls using the same assay to diagnose immunologic disorders correctly.  相似文献   
107.
The proteomic response to bacterial infection in a teleost fish (Paralichthys olivaceus) infected with Streptococcus parauberis was analyzed using label-free protein quantitation coupled with LC-MS(E) tandem mass spectrometry. A total of 82 proteins from whole kidney, a major lymphoid organ in this fish, were found to be differentially expressed between healthy and diseased fish analyzed 6, 24, 72 and 120 h post-infection. Among the differentially expressed proteins, those involved in mediating immune responses (e.g., heat shock proteins, cathepsins, goose-type lysozyme and complement components) were most significantly up-regulated by infection. In addition, cell division cycle 48 (CDC48) and calreticulin, which are associated with cellular recovery and glycoprotein synthesis, were up-regulated in the universal protein group, whereas the other proteins in that group were down-regulated. There was continuous activation of expression of immune-associated proteins during infection, but there was also loss of expression of proteins not involved in immune function. We expect that our findings regarding immune response at the protein level would offer new insight into the systemic response to bacterial infection of a major immune organ in teleost fish.  相似文献   
108.
目的:探讨肾移植术后人微小病毒B19感染所致纯红细胞再生障碍性贫血的诊断及其治疗。方法:回顾性分析4例肾移植术后纯红细胞再生障碍性贫血患者的临床特点,诊断方法,治疗过程及预后。结果:两周内在本中心接受肾移植手术的6例患者中,有4例在术后60天内均出现发热、血红蛋白进行性下降等相似症状;综合骨髓穿刺、ELISA方法检测血清特异性IgG、IgM等方法诊断为人微小病毒B19感染;经静脉注射免疫球蛋白、调整免疫抑制方案等综合治疗后,4例患者病情均明显缓解。结论:(1)贫血是肾移植术后患者感染人微小病毒B19的典型临床症状;(2)PCR检测和/或ELISA方法,结合骨髓穿刺及其他实验室指标可诊断人微小病毒感染;(3)静脉注射免疫球蛋白是肾移植术后人微小病毒B19感染导致PRCA的首选治疗方法,病情反复时,再次应用仍然有效。同时予以调整免疫抑制剂方案等综合治疗,可获得理想疗效。  相似文献   
109.
Synthetic antibody libraries with restricted chemical diversity were used to explore the intrinsic contributions of four amino acids (Tyr, Ser, Gly and Arg) to the affinity and specificity of antigen recognition. There was no correlation between nonspecific binding and the content of Tyr, Ser or Gly in the antigen-binding site, and in fact, the most specific antibodies were those with the highest Tyr content. In contrast, Arg content was clearly correlated with increased nonspecific binding. We combined Tyr, Ser and Gly to generate highly specific synthetic antibodies with affinities in the subnanomolar range, showing that the high abundance of Tyr, Ser and Gly in natural antibody germ line sequences reflects the intrinsic capacity of these residues to work together to mediate antigen recognition. Despite being a major functional contributor to co-evolved protein-protein interfaces, we find that Arg does not contribute generally to the affinity of naïve antigen-binding sites and is detrimental to specificity. Again, this is consistent with studies of natural antibodies, which have shown that nonspecific, self-reactive antibodies are rich in Arg and other positively charged residues. Our findings suggest that the principles governing naïve molecular recognition differ from those governing co-evolved interactions. Analogous studies can be designed to explore the roles of the other amino acids in molecular recognition. Results of such studies should illuminate the basic principles underlying natural protein-protein interactions and should aid the design of synthetic binding proteins with functions beyond the scope of natural proteins.  相似文献   
110.
The generation of recombinant antibodies (Abs) using phage display is a proven method to obtain a large variety of Abs that bind with high affinity to a given antigen. Traditionally, the generation of single-chain Abs depends on the use of recombinant proteins in several stages of the procedure. This can be a problem, especially in the case of cell-surface receptors, because Abs generated and selected against recombinant proteins may not bind the same protein expressed on a cell surface in its native form and because the expression of some receptors as recombinant proteins is problematic. To overcome these difficulties, we developed a strategy to generate single-chain Abs that does not require the use of recombinant protein at any stage of the procedure. In this strategy, stably transfected cells are used for the immunization of mice, measuring Ab responses to immunization, panning the phage library, high-throughput screening of arrayed phage clones, and characterization of recombinant single-chain variable regions. This strategy was used to generate a panel of single-chain Abs specific for the innate immunity receptor Toll-like receptor 2. Once generated, individual single-chain variable regions were subcloned into an expression vector allowing the production of recombinant Abs in insect cells, thus avoiding the contamination of recombinant Abs with microbial products. This cell-based system efficiently generates Abs that bind to native molecules on the cell surface, bypasses the requirement of recombinant protein production, and avoids risks of microbial component contamination.  相似文献   
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