No abstract available.
Glycosylation End Products, Advanced* ; Lysine*

Isopeptide bond-mediated molecular superglue is the irreversible covalent bond spontaneously formed by the side chains of lysine (Lys) and asparagine/aspartic acid (Asn/Asp) residues. The peptide-peptide interaction is specific, stable, and can be achieved quickly without any particular physicochemical factor. In the light of recent progress by domestic and foreign researchers, here we summarize the origin, assembly system and mechanism of isopeptide bond reaction, as well as the molecular cyclization and protein topological structure mediated by it. The prospect for its application in synthetic vaccine, hydrogel and bacterial nanobiological reactor is further discussed.
Cyclization ; Lysine ; Peptides ; chemistry ; Proteins

It has been known that ultraviolet B(UVB) light made an oxidative damage to lens proteins, lipids and nucleic acids to induce lens opacity. The aim of the study was to investigate the effect of bendazac lysine salt (Bendaline) tot the experimental cataract developed by UV irradiation. Forty rats were exposed to 0.1mW/cm2 of UVB radiation in the range 300-320 mm for 24 hours per day. Five control rats were not exposed UVB radiation. During the investigative period, we measured lens opacity with Scheimpflug camera every other week. Rats were divided into 9 groups according to the duration of UV radiation and initial time of bendazac lysine medication. Bendazac lysine was administered orally by 25mg/kg per day for 2 months. The opacities on anterior cortex, nucleus and posterior capsule began to appear 4 months after UVB irradiation. The longer duration of radiation, the more severe opacity of lens was observed, especially at the layers of posterior supranucleus, posterior cortex and posterior capsule and in the opacity area by retroillumination image. After UVB induced cataract was developed, the lens opacity was not changed nevertheless stop the UV irradiation. Lens opacity of bendazac lysine-treated groups was not severer than that of no medication groups. There were less opacities on 4 month irradiated group rather than 6 month irradiated group at the layers of nucleus and posterior cortex and in the opacity area. Anticataract action of bendazac lysine was effective in earlier cataract. In the group of bendazac lysine medication with UVB irradiation on same time, the prophylactic evidence of bendazac lysine was not observed.
Animals ; Cataract* ; Crystallins ; Lysine* ; Nucleic Acids ; Rats*

Authors are trying to prove the fact that Poly-L-lysine (PLL) might be mixed with alginate to enhance cell-to- matrix adhesion. Before that experiment, the proportion of preadipocytes in cells obtained from rat epididymal fat was detected, and PLL cytotoxicity on preadipocytes was measured. All cells harvested after third passage of culture were differentiated into adipocytes, and there was no decrease in the proliferation of preadipocytes in the culture media under the PLL concentration of 5 microgram/m4. These results suggest that all cells harvested from rat epididymal fat after 3rd passage of culture were preadipocytes and PLL has no cytotoxicity to preadipocytes of rats under the concentration of 5 microgram/mP.
Adipocytes ; Animals ; Culture Media ; Lysine* ; Rats*

The Scheimpflug photography was used to evauate objectively changes in lens opacity at a month interval in 143 eyes of 78 patients affected by early cataract. from Dec. 1993 to Dec. 1994. A total of 48 patients were treated daily with 1.5g bendazac-lysine, and 30 patients constituted the control group. We checked visual acuity and analyzed change of lens opacity by using axial densitometry and retroillumination of Scheimpflug photography after Bendaline(R) medication up to 9 months After treatment, improvement or no change of subjective visual acuity was observed in 65 eyes(78.3%) of treated group, whereas decrement in 35 eyes (58.3%) of control group. In the axial densitometry, the nuclear opacity began to improve after 3 months of medication and opacities of lens between anterior supranucleus and posterior capsule were statistically significant improved after 5 months of medication (p<0.05). There's no correlation in the change of opacity area under retroillumination (p>0.05). The result show that bendazac lysine may be effective in improvement of visual acuity and delay the formation of lens opacity in early cataract.
Cataract* ; Densitometry ; Humans ; Lysine ; Photography ; Visual Acuity

The lysine salt of Bendazac was orally administered(500mg daily) to 18 patients(29 eyes) suffering from senile or adult cataract, for the range of 2 to 6 months. The visual acuity tests and the evaluation of variations of lens opacities by means of slit lamp biomicroscopy showed some improvement in 3 eyes(10.3%) whereas no changes occurred in 24 eyes(82.8%) and aggravation in 2 eyes(6.9%). Although visual improvement was seen in 3 eyes, this was statistically not significant(p>0.1). Group treated with Bendazac lysine salt was not compared with the placebo group.
Adult* ; Cataract* ; Humans ; Lysine* ; Visual Acuity

Histone lysine methyltransferases (HKMTs) deposit methyl groups onto lysine residues on histones and play important roles in regulating chromatin structure and gene expression. The structures and functions of HKMTs have been extensively investigated in recent decades, significantly advancing our understanding of the dynamic regulation of histone methylation. Here, we review the recent progress in structural studies of representative HKMTs in complex with nucleosomes (H3K4, H3K27, H3K36, H3K79, and H4K20 methyltransferases), with emphasis on the molecular mechanisms of nucleosome recognition and trans-histone crosstalk by these HKMTs. These structural studies inform HKMTs' roles in tumorigenesis and provide the foundations for developing new therapeutic approaches targeting HKMTs in cancers.
Nucleosomes ; Histones/metabolism* ; Histone-Lysine N-Methyltransferase/metabolism* ; Lysine/metabolism* ; Methyltransferases/metabolism* ; Methylation

The occurence and development of tumors is a complicated process, which not only depends on the mutation or deletion of genes, but also is affected by epigenetic regulation. Accumulating evidences have shown that epigenetic modifications play fundamental roles in transcriptional regulation, heterochromatin formation, X chromosome inactivation, DNA damage response and tumor development. SET domain containing lysine methyltransferase 7 (SETD7) was initially identified as an important lysine methyltransferase, which methylated histone and non-histone proteins. These modifications play fundamental roles. Once this modification disorders, it can directly lead to cell abnormalities and cause many diseases. Studies have shown that SETD7 is related to the occurence and development of various tumors, but the methylation sites of SETD7 and its regulatory mechanism have not been fully elucidated. This article summarizes the research progress of the role of SETD7 on histone and non-histone methylation modification in tumors and the molecular mechanism, in order to provide new therapeutic targets for tumor pathogenesis and diagnosis.
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Humans ; Epigenesis, Genetic ; Histone-Lysine N-Methyltransferase/metabolism* ; Lysine/metabolism* ; Lung Neoplasms/genetics* ; Histones/metabolism*

Non-swelling cornea was prepared according to the method of Payrau. 1) Rabbit cornea without epithelium was treated with the vapor of 0.04% formalin at 4 degrees C for 48 hours, and then dehydrated with silica gel at room temperature for 48 hours. 2) Dehydrated cornea was soaked in the neutral solution of 0.5% L-lysine HCI for one hour, and in the neutral solution of 0.5% L-arginin HCl for one hour successively. 3) Non-swelling cornea was preserved in the desiccator with silica gel or in 0.02% merthiolate solution. Authors compared the hydration ratio of the non-swelling cornea with untreated cornea. Authors employed the chromotropic acid method to measure the amount of formaldehyde in the non-s-welling cornea and compared with the cornea treated only with formalin showed that: 1) Non-swelling cornea became hydrated within 30 minutes and remained constant thereafter in 0.9% saline solution at room temperature, whereas formalin treated cornea hydrated enormously within 3 hours. 2) The amount of formaldehyde in the non-swelling cornea was on the average 0.129 micro M/mg dry weight, and 3) The amount of formaldehyde in the formalin treated cornea was on the average 0.325 micro M/mg dry weight.
Cornea* ; Epithelium ; Formaldehyde ; Lysine ; Silica Gel ; Sodium Chloride ; Thimerosal

Topoisomerases and histone deacetylases (HDACs) are considered as important therapeutic targets for a wide range of cancers, due to their association with the initiation, proliferation and survival of cancer cells. Topoisomerases are involved in the cleavage and religation processes of DNA, while HDACs regulate a dynamic epigenetic modification of the lysine amino acid on various proteins. Extensive studies have been undertaken to discover small molecule inhibitor of each protein and thereby, several drugs have been transpired from this effort and successfully approved for clinical use. However, the inherent heterogeneity and multiple genetic abnormalities of cancers challenge the clinical application of these single targeted drugs. In order to overcome the limitations of a single target approach, a novel approach, simultaneously targeting topoisomerases and HDACs with a single molecule has been recently employed and attracted much attention of medicinal chemists in drug discovery. This review highlights the current studies on the discovery of dual inhibitors against topoisomerases and HDACs, provides their pharmacological aspects and advantages, and discusses the challenges and promise of the dual inhibitors.
DNA ; Drug Discovery ; Epigenomics ; Histone Deacetylases* ; Histones* ; Lysine ; Population Characteristics