Hematochezia in a Child With Heiner Syndrome.

Heiner syndrome (HS) is a food hypersensitivity disease that is mostly caused by cow's milk. The main features may include chronic or recurrent respiratory syndromes, pulmonary infiltrates on radiography, and even pulmonary hemosiderosis. However, gastrointestinal symptoms are rare in HS, which can lead to a misdiagnosis when the chief complaint is about the gastrointestinal system. Here, we report a case of HS complicated by severe hematochezia.

Retraction Note to: An assessment of transgenomics as a tool for gene discovery in Populus euphratica Oliv.

This article (Zhou et al. 2018) has been retracted by the authors because the sequence BIBAC 002A111F06 was incorrectly assigned to the wrong bacterial species. The BIBAC 002A111F06 sequence (GenBank Accession KC129717) reported in the paper was attributed to Populus euphratica Oliv. The BLAST search of this KC129717 sequence against the nr database at NCBI showed that it has very high similarity to a genomic sequence from the gram-negative bacteria Stenotrophomonas maltophilia. The bacterium associates with Populus euphratica Oliv. and DNA isolated from Populus euphratica Oliv. for the construction of the BIBAC clone library inlcuded DNA from Stenotrophomonas maltophilia. Therefore, the phenotype of the transgenic Arabidopsis line carrying the KC129717 sequence cannot be attributed to genes from Populus euphratica Oliv. The authors apologize for the confusion and misinterpretation of our data resulting from the incorrect sequence assignment. All authors agree to this retraction.

An assessment of transgenomics as a tool for gene discovery in Populus euphratica Oliv.

KEY MESSAGE: Transgenomics for gene discovery in Populus euphratica. Transgenomics, a member of the omics family of methodologies, is characterized as the introduction of DNA from one organism into another on a genome-wide scale followed by the identification of recipients with altered phenotypes. This strategy allows investigators to identify the gene(s) involved in these phenotypic changes. It is particularly promising for woody plants that have a long life cycle and for which molecular tools are limited. In this study, we constructed a large-insert binary bacterial artificial chromosome library of Populus euphratica, a stress-tolerant poplar species, which included 55,296 clones with average insert sizes of about 127 kb. To date, 1077 of the clones have been transformed into Arabidopsis thaliana via Agrobacterium by the floral dip method. Of these, 69 transgenic lines showed phenotypic changes represented by diverse aspects of plant form and development, 22 of which were reproducibly associated with the same phenotypic change. One of the clones conferring transgenic plants with increased salt tolerance, 002A1F06, was further analyzed and the 127,284 bp insert in this clone harbored eight genes that have been previously reported to be involved in stress resistance. This study demonstrates that transgenomics is useful in the study of functional genomics of woody plants and in the identification of novel gene(s) responsible for economically important traits. Thus, transgenomics can also be used for validation of quantitative trait loci mapped by molecular markers.

Experiment research of cisplatin implants inhibiting transplantation tumor growth and regulating the expression of KLK7 and E-cad of tumor-bearing mice with gastric cancer.

OBJECTIVE: To study the influence of cisplatin implants on transplantation tumor growth and the expression of tissue kallikrein-7 (KLK7) and E-cadherin (E-cad) in tumor-bearing mice with gastric cancer. METHODS: BALB/c nude mice were collected as experimental animal and were randomly divided into model control group (Group A), tail intravenous injection of cisplatin group (Group B), intratumor injection of cisplatin group (Group C) and cisplatin implants treatment group (Group D). After the drugs intervening, the weight and volume of transplantation tumors were measured on Day 20, Day 30 and Day 40 and serum and KLK7 and E-cad contents in transplanted tumor tissue were examined. RESULTS: On Day 20, Day 30 and Day 40 after treatment, the weight and volume of transplantation tumors of tumor-bearing mice in four groups were different (Group A > Group B > Group C > Group D). The contents of KLK-7 and E-cad in tumor tissue and serum of tumor-bearing mice in four groups were different (Group A > Group B > Group C > Group D in KLK-7) and (Group A < Group B < Group C < Group D in E-cad). The weight and volume, and KLK7 and E-cad contents of transplantation tumors in four groups were significant difference (P < 0.05). CONCLUSION: Cisplatin implants can inhibit the growth of transplanted tumor tissue and down-regulated KLK7 expression and up-regulated E-cad expression of tumor-bearing mice with gastric cancer.

Expression of serum Dickkopf-1 in gastric cancer patients.

OBJECTIVE: To explore the expression and clinical significance of DKK-1 protein in patients with gastric cancers. METHODS: Enzyme linked immuno sorbent assay was used to detect expressions of serum DKK-1 protein in 90 cases of gastric cancers, 50 cases of gastric benign disease and 40 healthy cases. The dynamic change in serum DKK-1 protein of gastric cancer patients who accepted radical operation for a month was also observed. RESULTS: The expression of serum DKK-1 protein in gastric cancer groups was significantly higher than that in gastric benign group's (P < 0.01) and in health control (P < 0.01). Serum DKK-1 level was increased gradually along with the progress of the disease. Serum DKK-1 levels were significantly higher in patients at TNM staging III and IV than patients at TNM staging I and II. Level of serum DKK-1 was related to microvascular invasion, differentiation degree and infiltration depth. Level of serum DKK-1 was significantly reduced in patients after radical surgery (P < 0.01). CONCLUSIONS: The expression of serum DKK-1 protein in gastric cancer patients is increased. Level of serum DKK-1 is related to TNM staging, microvascular invasion, differentiation degree and infiltration depth. DKK-1 detection can be used as a reference index in monitoring gastric cancer progress and biological behavior.

The peptidyl-prolyl isomerase activity of SlyD is not required for maturation of Escherichia coli hydrogenase.

Escherichia coli SlyD, which is involved in the biosynthesis of the metal cluster in the [NiFe]-hydrogenase enzymes, exhibits several activities including that of a peptidyl-prolyl isomerase (PPIase). Mutations that result in deficient PPIase activity do not produce corresponding decreases in the other activities of SlyD in vitro or in hydrogenase production levels in vivo.

The role of complex formation between the Escherichia coli hydrogenase accessory factors HypB and SlyD.

The Escherichia coli protein SlyD is a member of the FK-506-binding protein family of peptidylprolyl isomerases. In addition to its peptidylprolyl isomerase domain, SlyD is composed of a molecular chaperone domain and a C-terminal tail rich in potential metal-binding residues. SlyD interacts with the [NiFe]-hydrogenase accessory protein HypB and contributes to nickel insertion during biosynthesis of the hydrogenase metallocenter. This study examines the HypB-SlyD complex and its significance in hydrogenase activation. Protein variants were prepared to delineate the interface between HypB and SlyD. Complex formation requires the HypB linker region located between the high affinity N-terminal Ni(II) site and the GTPase domain of the protein. In the case of SlyD, the deletion of a short loop in the chaperone domain abrogates the interaction with HypB. Mutations in either protein that disrupt complex formation in vitro also result in deficient hydrogenase production in vivo, indicating that the contact between HypB and SlyD is important for hydrogenase maturation. Surprisingly, SlyD stimulates release of nickel from the high affinity Ni(II)-binding site of HypB, an activity that is also disrupted by mutations that affect complex formation. Furthermore, a SlyD truncation lacking the C-terminal metal-binding tail still interacts with HypB but is deficient in stimulating metal release and is not functional in vivo. These results suggest that SlyD could activate metal release from HypB during metallation of the [NiFe] hydrogenase.

Interactions of the Escherichia coli hydrogenase biosynthetic proteins: HybG complex formation.

Assembly of the active site of the [NiFe]-hydrogenase enzymes involves a multi-step pathway and the coordinated activity of many accessory proteins. To analyze complex formation between these factors in Escherichia coli, they were genomically tagged and native multi-protein complexes were isolated. This method validated multiple interactions reported in separate studies from several organisms and defined a new complex containing the putative chaperone HybG and the large subunit of hydrogenase 1 or 2. The complex also includes HypE and HypD, which interact with each other before joining the larger complex.

A role for SlyD in the Escherichia coli hydrogenase biosynthetic pathway.

The [NiFe] centers at the active sites of the Escherichia coli hydrogenase enzymes are assembled by a team of accessory proteins that includes the products of the hyp genes. To determine whether any other proteins are involved in this process, the sequential peptide affinity system was used. The analysis of the proteins in a complex with HypB revealed the peptidyl-prolyl cis/trans-isomerase SlyD, a metal-binding protein that has not been previously linked to the hydrogenase biosynthetic pathway. The association between HypB and SlyD was confirmed by chemical cross-linking of purified proteins. Deletion of the slyD gene resulted in a marked reduction of the hydrogenase activity in cell extracts prepared from anaerobic cultures, and an in-gel assay was used to demonstrate diminished activities of both hydrogenase 1 and 2. Western analysis revealed a decrease in the final proteolytic processing of the hydrogenase 3 HycE protein, indicating that the metal center was not assembled properly. These deficiencies were all rescued by growth in medium containing excess nickel, but zinc did not have any phenotypic effect. Experiments with radioactive nickel demonstrated that less nickel accumulated in DeltaslyD cells compared with wild type, and overexpression of SlyD from an inducible promoter doubled the level of cellular nickel. These experiments demonstrate that SlyD has a role in the nickel insertion step of the hydrogenase maturation pathway, and the possible functions of SlyD are discussed.

Reduction of antigenicity and allergenicity of genetically modified egg white allergen, ovomucoid third domain.

Ovomucoid (Gal d1) is a major allergen in hen egg white, consisting of three tandem domains. In this study, five genetically modified third domain (DIII) mutants, which were substituted single or double amino acids within its IgE and IgG epitopes were compared with those prepared and their antigenicity and allergenicity with native analogue using Western immunoblot and enzyme-linked immunosorbent assay. The replacement of phenylalanine at 37 (F37) position with methionine caused drastical loss of IgG and IgE binding activities of human sera derived from egg allergic patients as well as disruption of the alpha-helix structure which comprises a part of the IgG and IgE epitopes. Substituting glycine at 32 position in conjunction with F37 showed a synergistic effect of decreasing antigenicity. The present study indicated that glycine 32 and phenylalanine 37 have an important role on its antigenicity and allergenicity as well as structural integrity of ovomucoid DIII.

Comparative studies on antigenicity and allergenicity of native and denatured egg white proteins.

The binding activities of IgG and IgE antibodies from egg-allergic patients to physically or chemically treated egg white proteins were examined and compared with those of rabbit anti-egg white IgG antibodies. The sera from eight patients and four rabbit antibodies were used in this study. The binding activities of human IgG antibody to partially denatured ovotransferrin (Tf), ovalbumin (OA), and lysozyme (Lys) forms were increased, whereas carboxymethylation (RCM) and heat treatment caused a dramatic decrease in the antigenicity of Tf and ovomucoid (OVM). Tf and OVM were major immunogenic antigens for the rabbit IgG response. Urea also caused Tf to exhibit greater rabbit IgG binding activity. In contrast, human and rabbit antibodies did not react with ovomucin. Partially denatured Tf and Lys also induced strong IgE binding activities. The allergenicity of Tf, OVM, and Lys was decreased by RCM, whereas OA retained its binding capacity. These results suggested that anti-OA IgE recognizes more sequential epitopes and that anti-OVM and Lys antibodies recognize both conformational and sequential epitopes. Tf and OVM were dominant allergens for the IgE antibodies of anaphylaxis patients, whereas IgE from atopic patients bound more strongly with OA and OVM.