The third edition of Principles of Tissue Engineering attempts to incorporate the latest advances in the biology and design of tissues and organs and simultaneously to connect the basic sciences — including new discoveries in the field of stem cells — with the potential application of tissue engineering to diseases affecting specific organ systems.
Acetylation of the amino terminus of the core histones H3 and H4 induces an open chromatin conformation that promotes transcription initiation. Histone acetylases are components of coactivator complexes recruited to
promoter/enhancer regions by sequence-specific transcription factors during the activation of genes (Fig. 80-4). Histone deacetylases (HDACs; at least 17 are encoded in the human genome) are recruited to genes by transcriptional repressors and prevent the initiation of gene transcription.
Chymases are chymotrypsin-like serine proteases that are found in large
amounts in mast cell granules. So far, the extended cleavage specificities of
eight such chymases have been determined, and four of these were shown
to have a strong preference for acidic amino acids at position P2¢. These
enzymes have basic amino acids in positions 143 and 192 (Arg and Lys,
Control analysis of the glycolytic flux was carried out in two fast-growth
tumor cell types of human and rodent origin (HeLa and AS-30D, respect-ively). Determination of the maximal velocity (Vmax) of the 10 glycolytic
enzymes from hexokinase to lactate dehydrogenase revealed that hexokin-ase (153–306 times) and phosphfructokinase-1 (PFK-1) (22–56 times) had
higher over-expression in rat AS-30D hepatoma cells than in normal
freshly isolated rat hepatocytes.
A strength of NMR spectroscopy is its ability to monitor, on an atomic
level, molecular changes and interactions. In this review, which is intended
for non-spectroscopists, we describe major uses of NMR in protein science
beyond solution structure determination.
The product chain length determination mechanism of type II geranyl-geranyl diphosphate synthase from the bacterium, Pantoea ananatis, was
studied. In most types of short-chain (all-E) prenyl diphosphate synthases,
bulky amino acids at the fourth and/or fifth positions upstream from the
first aspartate-rich motif play a primary role in the product determination
We have previously demonstrated thata-mannosyl ceramide and its deriva-tives promote immune responses of NK1.1
invariant Va19-Ja33 T cell
receptor (TCR) a
T cells (Va19 NKT cells). In this study, attempts were
made to determine the structural requirements for natural ligands for Va19
Aniline dioxygenase is a multicomponent Rieske nonheme-iron dioxygenase
enzyme isolated from Acinetobactersp. strain YAA. Saturation mutagen-esis of the substrate-binding pocket residues, which were identified using a
homology model of theasubunit of the terminal dioxygenase (AtdA3), was
used to probe the molecular determinants of AtdA substrate specificity.
Human amylin is a small fibrillogenic protein that is the major constituent
of pancreatic islet amyloid, which occurs in most subjects with type 2 dia-betes. There is evidence that it can elicitin vitro apoptosis in isletb-cells,
but the physical properties that underpin its cytotoxicity have not been
ThepyrGgene fromLactococcus lactisencodes CTP syn-thase (EC 220.127.116.11), an enzyme converting UTP to CTP. A
series of strains were constructed with different levels of
pyrGexpression by insertion of synthetic constitutive pro-moters with different strengths in front ofpyrG.These
strains expressed pyrGlevels in a range from 3 to 665%
relative to thewild-type expression level.Decreasing the level
of CTP synthase to 43% had no effect on the growth rate,
showing that the capacity of CTP synthase in the cell is
in excess in a wild-type strain. ...
Thea-melanocyte-stimulating hormone (aMSH) receptor
(MC1R) is amajordeterminant ofmammalianskinandhair
pigmentation. Binding ofaMSHtoMC1Rinhuman mel-anocytes stimulates cell proliferation and synthesis of pho-toprotective eumelanin pigments. Certain MC1Ralleles
have been associated with increased riskof melanoma. This
can be theoretically considered on two grounds. First, gain-of-function mutations may stimulate proliferation, thus
promoting dysplastic lesions.
A series of thylakoid membrane proteins, including PsbX, PsbY and PsbW, are synthesized with cleavable signal peptides yet inserted using none of the known Sec/SRP/Tat/ Oxa1-type insertion machineries. Here, we show that, although superﬁcially similar to Sec-type signal peptides, these thylakoidal signal peptides contain very diﬀerent determinants.
A new automated procedure for preconcentration and analysis of anionic surfactants in water using solid-phase extraction (SPE) in a flow injection (Fl) system together with an UV-vis detection is reported in this paper. The method involves extraction of blue coloured ion-pair complex of anionic surfactants and methylene blue into solid phase and their elution from the SPE column with organic solvent (chloroform stabilised with methanol) and subsequent measurement in an UV-vis flow cell at 650 nm. The system is well optimised before to apply for analysis of real samples.
Mobilization of hematopoietic stem and progenitor cells (HSPCs) from the
bone marrow to the peripheral blood is utilized in clinical HSPC transplan-tation protocols. Retention of HSPCs in the bone marrow is determined by
relationships between the chemokine chemokine (C-X-C motif) ligand 12
(CXCL12) and its major receptor
Despite the aberrant expression of cholinesterases in tumours, the question of
their possible contribution to tumorigenesis remains unsolved. The identifica-tion in kidney of a cholinergic system has paved the way to functional studies,
but details on renal cholinesterases are still lacking. To fill the gap and to
determine whether cholinesterases are abnormally expressed in renal
tumours, paired pieces of normal kidney and renal cell carcinomas (RCCs)
were compared for cholinesterase activity and mRNA levels....
Circulating tumour necrosis factor-a(TNFa) levels, which are elevated in
obesity-associated insulin resistance and diabetes, inhibit insulin signalling at
several points in the signalling cascade. The liver is critical in maintaining cir-culating glucose levels and, in a preliminary investigation using the human
hepatoma (HepG2) cell line in this study, we demonstrated the role of TNFa
in the regulation of this phenomenon and determined the underlying
We determined differentially expressed genes in HT29 human colon cancer
cells, both after short treatment with methotrexate (MTX) and after the
resistance to MTX had been established. Screening was performed using
Atlas Human Cancer 1.2K cDNA arrays. The analysis was carried out
using Atlasimage 2.01 andgenespring6.1 software.
External quality assessment schemes are evaluated by method-dependent consensus values or by method independent target
values, determined with reference measurement procedures. The
reference measurement procedures yield values having a high
trueness and precision with a defined uncertainty of measure-ment. The great advantage of the reference measurement proce-dure is that the comparability of results in the different medical
laboratories is promoted and improved intending in the same ref-erence interval for an analyte in all laboratories. ...
(All-E) prenyl diphosphate synthases catalyze the con-secutive condensation of isopentenyl diphosphates with
allylic prenyl diphosphates, producing products with vari-ous chain-lengths that are unique for each enzyme. Some
short-chain (all-E) prenyl diphosphate synthases, i.e.
farnesyl diphosphate synthases and geranylgeranyl
diphosphate synthases contain characteristic amino acid
sequences around the allylic substrate binding sites, which
have been shown to play a role in determining the chain-length of the product....