5-Aminolevulinic Acid: Production by Fermentation,and Agricultural and Biomedical Applications

Abstract

Research involving differentiated embryonic stem (ES) cells may revolutionize the study of liver disease, improve the drug discovery process, and assist in the development of stem-cell-based clinical therapies. Generation of ES cell-derived hepatic tissue has benefited from an understanding of the cytokines, growth factors and biochemical compounds that are essential in liver development, and this knowledge has been used to mimic some aspects of embryonic development in vitro. Although great progress has been made in differentiating human ES cells into liver cells, current protocols have not yet produced cells with the phenotype of a mature hepatocyte. There is a of disease models have been examined concerning whether stem cells can correct liver disease. It is a bit premature to conclude that hepatocytes can be generated from non-hepatic cells in culture that will be clinically useful. Standard criteria will need to be developed to assess the extent to which human stem cell-derived hepatocytes have been produced.     

Solubilization of Chicken Feather Keratin by Ammonium Copper Hydroxide (Schweitzer’s Reagent)

Chicken feather powder was solubilized by Schweitzer’s reagent with shaking in the presence of air and the soluble feather keratin was prepared by dialyzing this extract against running water. Cystine residues in the starting feather keratin was converted to cysteic acid residues in the solubilized derivatives by air oxygen. Copper was bound fairly tightly to the solubilized protein and this copper-protein complex was separated into four fractions by CM- and DEAE-cellulose column chromatography. Each fraction had varied amount of bound copper, having a broad distribution of the molecular weight between 10,000 and 60,000 Sephadex column chromatographically. Although the amino acid composition of all separated feather keratin fractions were quite similar, the different electrophoretic patterns were observed among them by DISC electrophoresis.     

Angiogenesis in the mouse retina: a model system for experimental manipulation

The vascular system of the mouse retina provides a useful model for analyzing the molecular and cellular mechanisms regulating angiogenesis because (1) hierarchical vascular networks are newly formed only after birth, (2) the cellular components involved in angiogenesis are well characterized, and (3) all the processes are accessible for monitoring and manipulation. In this article, we present an overview of our current understanding of the process of retinal angiogenesis and describe a number of methodologies applicable to experimental manipulation of the retinal vascular system.     

A case of first trimester prenatal diagnosis of 21-hydroxylase deficiency with human complement C4 cDNA probe

Early prenatal diagnosis of 21-hydroxylase (21-OHase) deficiency would enable treatment to be done to protect the fetus from masculinization and/or life-threatening adrenal crisis at birth. We report here the prenatal diagnosis of 21-OHase deficiency with human complement component C4 cDNA to probe DNA from chorionic villi at 10 weeks of gestation. Southern analysis with human C4 cDNA identified TaqI restriction fragment length polymorphisms (RFLPs) in the family. Family analysis with these RELPs showed that the fetus was not affected at greater than 99% probability, because the frequency of recombination between the 21-OHase B gene and the C4 gene would be extremely low.     

Elongation of oligonucleotides in the 3'-direction with activated mononucleotides and their analogs using RNA ligase.

P1-Adenosine 5'-P2-2',3'-ethoxymethylidene nucleosides [A(5')ppN(Em)] from four common nucleosides have been prepared and used for single addition of nucleotides to elongate oligonucleotide chains in the 3'-direction in RNA ligase reaction. U-U-C, T-U-C and A-C-C were used as acceptors. Structural dependence in these acceptors was found to be smaller compared to joining reactions between oligonucleotides. Adenosine analogs including 8-bromo-, 2'-fluoro-, 2'-azido-, 8,2'-O-cyclo-, 8,2'-S-cyclo-adenosine, arabinosyladenine and 2'-deoxyadenosine were added to the 3'-end of A-C-C by adenylation chemically followed by joining with RNA ligase. Symmetrical 5'-pyrophosphates of 8-bromo-, 2'-fluoro- and 2'-azido-adenosine were not recognized as donor substrates.     

Novel system evaluating in vivo pathogenicity of desmoglein 3-reactive T cell clones using murine pemphigus vulgaris

Autoreactive T cells are thought to be involved in the pathogenesis of autoimmune diseases, but evidence for their direct pathogenicity is almost lacking. Herein we established a unique system for evaluating the in vivo pathogenicity of desmoglein 3 (Dsg3)-reactive T cells at a clonal level in a mouse model for pemphigus vulgaris (PV), an autoimmune blistering disease induced by anti-Dsg3 autoantibodies. Dsg3-reactive CD4(+) T cell lines generated in vitro were adoptively transferred into Rag-2(-/-) mice with primed B cells derived from Dsg3-immunized Dsg3(-/-) mice. Seven of 20 T cell lines induced IgG anti-Dsg3 Ab production and acantholytic blister, a typical disease phenotype, in recipient mice. Comparison of the characteristics between pathogenic and nonpathogenic Dsg3-reactive T cell lines led to the identification of IL-4 and IL-10 as potential factors associated with pathogenicity. Further in vitro analysis showed that IL-4, but not IL-10, promoted IgG anti-Dsg3 Ab production by primed B cells. Additionally, adenoviral expression of soluble IL-4Ralpha in vivo suppressed IgG anti-Dsg3 Ab production and the PV phenotype, indicating a pathogenic role of IL-4. This strategy is useful for evaluating the effector function of autoreactive T cells involved in the pathogenesis of various autoimmune diseases.     

Synthesis of novel alpha-C-glycosylamino acids and reverse regioselectivity in Larock's heteroannulation for the synthesis of the indole nucleus

An alpha-C-iodoethynylglucose derivative was coupled with an L-serine-derived zinc-copper reagent to give alpha-C-glucosylpropargyl glycine, which underwent palladium catalyzed-heteroannulation with o-iodoaniline to give not alpha-C-glucosyl-tryptophan but alpha-C-glucosyl-iso-tryptophan. This is the first observation of complete reverse regioselectivity to Larock's proposal.     

Increase in leaf mass per area benefits plant growth at elevated CO2 concentration

An increase in leaf mass per area (MLA) of plants grown at elevated [CO2] is often accompanied by accumulation of non-structural carbohydrates, and has been considered to be a response resulting from source-sink imbalance. We hypothesized that the increase in MLA benefits plants by increasing the net assimilation rate through maintaining a high leaf nitrogen content per area (NLA). To test this hypothesis, Polygonum cuspidatum was grown at ambient (370 micro mol mol-1) and elevated (700 micro mol mol-1) [CO2] with three levels of N supply. Elevated [CO2] significantly increased MLA with smaller effects on NLA and leaf mass ratio (fLM). The effect of change in MLA on plant growth was investigated by the sensitivity analysis: MLA values observed at ambient and elevated [CO2] were substituted into a steady-state growth model to calculate the relative growth rate (R). At ambient [CO2], substitution of a high MLA (observed at elevated [CO2]) did not increase R, compared with R for a low MLA (observed at ambient [CO2]), whereas at elevated [CO2] the high MLA always increased R compared with R at the low MLA. These results suggest that the increase in MLA contributes to growth enhancement under elevated [CO2]. The optimal combination of fLM and MLA to maximize R was determined for different [CO2] and N availabilities. The optimal fLM was nearly constant, while the optimal MLA increased at elevated [CO2], and decreased at higher N availabilities. The changes in fLM of actual plants may compensate for the limited plasticity of MLA.