3-Hydroxy-3-methylglutaric aciduria

3-Hydroxy-3-methylglutaric aciduria was found in a newborn infant whose parents are first cousins. The patient presented at 5 days of life with hyperammonemia, hypoglycemia, and metabolic acidosis. There was no ketonuria. Diagnosis was made by analysis of the pattern of organic acids excreted in the urine. A profound deficiency in activity of 3-hydroxy-3-methylglutaryl-coenzyme A lyase was found in cultured skin fibroblasts. The parents had intermediate levels of enzyme activity.     

3-Hydroxy-3-Methylglutaric Aciduria

3-Hydroxy-3-methylglutaric aciduria was found in a newborn infant whose parents are first cousins. The patient presented at 5 days of life with hyperammonemia, hypoglecemia, and metabolic acidosis. There was no ketonuria. Diagnosis was made by analysis of the pattern of organic acids excreted in the urine. A profound deficiency in activity of 3-hydroxy-3-methylglutaryl-coenzyme A lyase was found in cultured skin fibroblasts. The parents had intermediate levels of enzyme activity.     

Fetal thymocyte potential for T cell receptor Vγ3-Jγ1 junctional modification

Junctional modifications of T cell receptor (TcR) and immunoglobulin (Ig) gene joining regions provide great diversity to respective protein repertoires. The addition of non-germ-line-encoded nucleotides (N-regions) in the V-Jγ junction is one such modification which is developmentally regulated, rarely evident in the fetal animal, but common in the adult. A question has recently arisen as to whether developmentally patterned N-region additions in V-Jγ joins are a reflection of T cell progenitors which are committed to particular types of rearrangement prior to the event, or of changing environmental influences on uncommitted cell populations. To address this question with regard to theVγ3-Jγ1 join, T cells were examined in the fetal thymic organ culture (FTOC), a system with which the environment of early progenitor cells could be deliberately altered. At various times following FTOC initiation, cells were isolated for examination by the polymerase chain reaction, cloning and sequencing. Vγ3-Jγl sequences within genomic DNA as well as cDNA were evaluated. Data from these studies revealed frequent N-region additions within V-Jγ joins among day 14 fetal thymocyte populations, a situation dissimilar from that in vivo. Also dissimilar from the in vivo situation was the degree of exonuclease activity evident in FTOC. The canonical Vγ3-Jγl join (a frequent junction lacking N-region addition) was recognized in all experiments, but was least common among DNA versus cDNA sequences. Results illustrate that early progenitor cell populations are not programmed to exclude junctional modifications from Vγ3-Jγ1 joins.     

γδ cells involved in contact sensitivity preferentially rearrange the Vγ3 region and require interleukin-7

Ptak and Askenase showed that both αβ and γδ cells are required for transfer of contact sensitivity (CS). This study confirms that day 4 immune cells depleted of γδ cells fail to transfer CS to trinitrochlorobenzene (TNP-Cl) systemically and demonstrates that administration of anti-γδ monoclonal antibodies (mAb) in vivo abolishes the CS reaction. Moreover, γδ cells accumulate at the antigen challenge site: these cells have the unusual phenotype CD8α⁺, CD8β^-, IL-4 R⁺ which we suggest is due to their state of activation. Following immunization with contact sensitizer on the skin, the absolute number of γδ cells increases in the regional lymph nodes with a peak at 4 days. Of the γδ cells, 80%, both in the lymph nodes of TNP-Cl-immune mice and accumulating at the antigen challenge site are Vγ3⁺. The γδ cells expressing Vγ3, which is characteristic of dendritic epithelial T cells (DETC), obtained 4 days after sensitization, proliferate in response to interleukin (IL)-7, but only poorly to IL-2 and IL-4. They also respond to concanavalin A and immobilized anti-γδ mAb, but not to haptens or heat-shocked syngeneic spleen cells. Furthermore, injection of mice with mAb to IL-7 inhibits accumulation of Vγ3⁺ cells both in the lymph nodes after skin sensitization and at the antigen-challenge site. Altogether, these results strongly support the view that DETC are related to, or the original source of, the γδ cells found in the lymph node after skin sensitization and at the site of challenge, and that IL-7 is implicated in these phenomena.     

Hypoxia Increases Serum Amyloid A3 (SAA3) in Differentiated 3T3-L1 Adipocytes

Hypoxia has been implicated as a possible cause of adipose tissue inflammation. Furthermore, the acute phase protein serum amyloid A (SAA) has been associated with the modulation of the adipogenic process, and it is well-known that obese individuals have increased levels of SAA. The effect of hypoxia in the expression and production of SAA was examined in murine 3T3-L1 adipocytes. Hypoxia leads to a substantial increase in SAA3 mRNA and protein level, apparently in a time-dependent manner (threefold in 48 h), in fully differentiated 3T3-L1, followed by reestablishment of gene expression to basal levels after 24 h of reoxygenation. Hypoxia-induced SAA may be one of the key molecules to the development of the inflammatory response in adipose tissue.     

γδ cells regulate autoimmunity

γδ cells are attractive candidates for mediators of autoimmune disease. They can expand in germ-free mice, probably through recognition of autoantigens, and γδ-cell-deficient mice, unlike mice deficient in αβ T cells or B cells, show no severe defects in the immune response to foreign antigen challenge. A capacity of γδ cells to effect or regulate tissue damage is also plausible, given their ready localization to tissues, and their myriad of effector functions. Added to this, attempts to reconstruct the physiological course of autoimmune diseases with only autoreactive αβ T cells seem invariably to fall short for lack of other unidentified players. γδ cells and their putative ligands have been linked to autoimmune conditions, and recent experiments confirm that γδ cells play a significant role in autoimmune disease in vivo.     

Assembly of the TCR/CD3 complex: CD3ϵ/δ and CD3ϵ/γ dimers associate indistinctly with both TCRα and TCRβ chains. Evidence for a double TCR heterodimer model

The TCR/CD3 complex is composed of six subunits which are expressed on the cell surface in a coordinate fashion after assembly in the endoplasmic reticulum (ER). The TCR/CD3 complex is assembled after a series of pairwise interactions involving the formation of dimers of CD3ϵ with either CD3γ or CD3δ. These dimers assemble with TCRα and TCRβ chains, and finally, the CD3ζ homodimer is added to allow export of the full complex from the ER. A model has been proposed suggesting that during assembly the CD3ϵ/CD3γ dimer interacts exclusively with TCRβ and the CD3ϵ/CD3δ dimer with TCRα to form a complex with a single TCRα/β heterodimer. We show in this study, by immunoprecipitation and two-dimensional gel electrophoresis, that in the human T cell line Jurkat as well as in total human thymocytes, this preferential interaction does not occur and instead, the CD3ϵ/CD3γ and CD3ϵ/CD3δ dimers associate with both TCR chains simultaneously and indistinctly. These data are confirmed by the analysis of the TCRα-negative T cell line MOLT-4 in which TCRβ is found separately associated with CD3ϵ/CD3γ and with CD3ϵ/CD3δ dimers. Indirectly, our results support a model of stoichiometry in which two TCRα/β heterodimers are present in a TCR/CD3 complex. Furthermore, immunoprecipitation with anti-CD3γ and anti-CD3δ antibodies from 1 % NP40 and 1 % Brij96 cell lysates showed that these subunits form independent partial complexes which are cross-linked through the CD3ζ homodimer. This suggests that CD3ζ mediates the interaction between both TCRα/β heterodimers contained in the double TCR complex. Further proof for this hypothesis is obtained after analysis of a Jurkat cell transfectant containing a point mutation in the transmembrane domain of TCRβ that impairs the association of CD3ζ. In this mutant cell line, unlike a control line with wild-type TCRβ, the CD3γ- and CD3δ-containing complexes were found completely independent. Altogether, these results support a model of TCR/CD3 assembly and stoichiometry in which two TCR-α/β heterodimers form two hemicomplexes containing either CD3ϵ/γ or CD3ϵ/δ dimers which become associated via the CD3ζ homodimer.     

DNM3OS Facilitates Ovarian Cancer Progression by Regulating miR-193a-3p/MAP3K3 Axis

PurposeLong non-coding RNAs (lncRNAs) are essential regulators in the development of ovarian cancer (OC). Nonetheless, the function of lncRNA DNM3 opposite strand/antisense RNA (DNM3OS) in OC remains unclear. This work aimed to investigate the biological roles and underlying mechanisms of DNM3OS in OC.Materials and MethodsQuantitative real-time polymerase chain reaction was conducted to examine DNM3OS, microRNA (miR)-193a-3p, and mitogen-activated protein kinase 3 (MAP3K3) mRNA expression in OC tissues and cell lines. Kaplan-Meier survival analysis was employed to analyze the relationship between DNM3OS expression and the prognosis of OC patients. Cell counting kit-8, 5-ethynyl-2′-deoxyuridine, and transwell experiments were conducted to monitor cell proliferation, migration, and invasion, respectively. Western blot was applied to examine epithelial-mesenchymal transition associated protein (E-cadherin and N-cadherin) expression. Luciferase reporter gene and RNA immunoprecipitation experiments were performed to confirm the relationships among DNM3OS, miR-193a-3p, and MAP3K3. Pearson''s correlation analysis was adopted to analyze the correlations among DNM3OS, miR-193a-3p, and MAP3K3 mRNA.ResultsDNM3OS expression was remarkably increased in OC tissues and cell lines, which was associated with the unfavorable prognosis of the patients. DNM3OS overexpression enhanced OC cell proliferation, migration, and invasion; suppressed E-cadherin protein expression; and facilitated N-cadherin protein expression, while the transfection of miR-193a-3p mimics had the opposite effects. DNM3OS directly interacted with miR-193a-3p, and miR-193a-3p targeted MAP3K3 by directly binding to 3′UTR. DNM3OS could up-regulate the expression of MAP3K3 via repressing miR-193a-3p expression.ConclusionDNM3OS, as an oncogenic lncRNA, increases the malignancy of OC cells via regulation of an miR-193a-3p/MAP3K3 axis.     

14-3-3蛋白的研究进展

14-3-3是一个在真核生物中广泛表达的酸性蛋白家族，主要以同源/异源二聚体形式存在，通过磷酸化丝/苏氨酸作用与靶蛋白或靶蛋白的2个结构域结合。7种不同亚型的高度保守的14-3-3蛋白与人类细胞中多种不同的信号通路有密切的关系。14-3-3通过调节靶蛋白间的相互作用在信号转导途径中发挥调控作用。     

Electrochemical copolymerization of 3-dodecylthiophene and 3-methylthiophene

3-Dodecylthiophene ( 1a ) and 3-methylthiophene ( 1b ) were copolymerized electrochemically. The visible and IR spectra of the neutral copolymers prove the copolymers to be of random structure, which can be denoted as that of poly(3-alkyl-2,5-thienylene)s. 1b polymerizes with preference over 1a . With increasing fraction of monomeric units of 1b in the copolymers, the conductivity increases and the solubility of the neutral copolymers decreases. The copolymer containing 58 mol-% monomeric units of 1b has a high conductivity of 220 S/cm and a good solubility of 75 wt.-% in chloroform. ¹H NMR spectra of poly(3-dodecylthienylene) and copolymers show two chemical shifts for the α(1)-methylene protons of the monomeric units of 1a as well as of the methyl protons of the monomeric units of 1b . This fact may be explained by the presence of head-to-head and other constitutions.     

Sepharose-C3

Summary. Effective conditions were devised for the specific depletion from lymphocyte populations of complement receptor lymphocytes (CRL) on columns of Sepharose-C3. CRL among both human and murine lymphocytes were found by this method to be a subpopulation of B cells.