Chaperone-like effect of the linker on the isolated C-terminal domain of rabbit muscle creatine kinase.

Intramolecular chaperones (IMCs), which are specific domains/segments encoded in the primary structure of proteins, exhibit chaperone-like activity against the aggregation of the other domains in the same molecule. In this research, we found that the truncation of the linker greatly promoted the thermal aggregation of the isolated C-terminal domain (CTD) of rabbit muscle creatine kinase (RMCK). Either the existence of the linker covalently linked to CTD or the supply of the synthetic linker peptide additionally could successfully protect the CTD of RMCK against aggregation in a concentration-dependent manner.

[Tumors of different histological type in unilateral salivary glands: a case report].

Tumors of synchronous benign and malignant in unilateral salivary glands have rarely been reported. A case of 21-year-old girl who was diagnosed as synchronously adenoid cystic carcinoma of the left parotid and pleomorphic adenoma of the left submandibular gland. The classification, clinic pathology, diagnosis, possible mechanism were discussed based on similar literatures.

[Effect of focal adhesion kinase on biological characteristics of Tca8113 tongue squamous cell carcinoma].

Objective: To investigate the effect of FAK on biological characteristics of tongue squamous cell carcinoma cell Tca8113.

Methods: Lipofect was used to transfect FAK into Tca8113 cell lines. The difference in expression of FAK between the transfected and non-transfected cell lines was detected by immunofluorescence assay.

[Function of P63 on the development of salivary glands].

Objective: To study the expression of P63 in human salivary gland development and the existing of salivary gland stem cells.

Methods: 24 embryonic salivary gland samples in different stage, 10 normal salivary gland samples were collected. HE-stained and immunochemistry stain were used.

Role of the linker between the N- and C-terminal domains in the stability and folding of rabbit muscle creatine kinase.

Domain-domain interactions may be very important to the structure and functions of many multidomain proteins. However, little is known about the role of the linker in the folding, stability and function of multidomain proteins. In this research, muscle creatine kinase (CK), a dimeric two-domain protein, was used as a model protein to investigate the role of the linker in CK activity, stability and folding by mutational analysis.

Exploration of the polar microenvironment around the reactive cysteine in rabbit muscle creatine kinase.

The polar microenvironment around the reactive Cys283 of rabbit muscle creatine kinase was explored using kinetic analysis of substrates reaction in the presence of modifiers. In the present study, three specific sulphydryl reagents, 5,5'-dithiobis(2-nitrobenzoic acid), 6,6'-dithiodinicotinic acid and 2,2'-dithiodipyridine, were applied as modifiers to react with Cys283 of creatine kinase. The inactivation kinetics of creatine kinase by the modifiers was analyzed.

[Expression and clinical significance of focal adhesion kinase in oral squamous cell carcinoma].

Objective: To study the correlation between expression levels of focal adhesion kinase (FAK) in oral squamous cell carcinoma (OSCC) and clinical prognosis with pathologic parameters.

Methods: Eighty paraffin embedded tissue specimens of OSCC were studied by immunohistochemistry. The data was analyzed by SPSS statistical software.

Sodium barbital is a slow reversible inactivator of rabbit-muscle creatine kinase.

As a depressant of the central nervous system, the clinical effect of sodium barbital has been extensively studied. Here we report on sodium barbital as an inhibitor of rabbit-muscle creatine kinase (CK), which plays a significant role in energy homeostasis in the muscles. Although sodium barbital gradually inhibits the activity of CK with increased concentration, the inhibition effect can be completely reversed by dilution, indicating that the inactivation process is reversible.

[Expression of deltaNp63 in salivary gland tumours].

Objective: To detect the expression of deltaNp63 in human salivary gland tumor and analyze its role in the malignant salivary gland tumors.

Methods: Collecting the samples from 68 cases of pathologically proven salivary gland tumours and investigating the microscopic sections with HE stain and immunohistochemical-SP stain.

Results: It was found that the expression of deltaNp63 is gradually increased in the malignant tumours, the myoepithelial cells and the basal cells of the salivary gland tumors are positive, and the expression of deltaNp63 is correlated directly with benign and malignant tumor.

Sequential events in ribonuclease A thermal unfolding characterized by two-dimensional infrared correlation spectroscopy.

The conformational changes in the thermal denaturation of bovine pancreatic ribonuclease A was followed with infrared spectra and analyzed by second derivative and two-dimensional correlation techniques. By analyzing the sequential events in each transition stage, the results were consistent with a step-wise thermal denaturation mechanism in which the structural adjustment of the N-terminal and the opening of the central structure of the protein come before the main unfolding process. Non-native turns were found to form along with the unfolding of the native structures.

Oligomerization and aggregation of bovine pancreatic ribonuclease A: characteristic events observed by FTIR spectroscopy.

Nonnative protein aggregation, which is a common feature in biotechnology, is also a clinical feature in more than 20 serious degenerative diseases. We studied the specific events of bovine pancreatic ribonuclease A thermal aggregation by a combination of second derivative infrared analysis and two-dimensional infrared correlation spectroscopy. By comparing the events that occur in reversible and irreversible thermal unfolding processes, certain events that were related to protein aggregation were characterized.

[Clinicopathological study of Ewing's sarcoma/primitive neuroectodermal tumor in oral and maxillofacial region].

Objective: To study the clinicopathological features and diagnostic criteria of Ewing's sarcoma/primitive neuroectodermal tumor (Ewing's sarcoma/PNET) in oral and maxillofacial region.

Methods: There were 15 patients with Ewing's sarcoma/PNET in the last 35 years at our hospital, aged 1-49 years and mean 14.5 years.

Conformational change in the C-terminal domain is responsible for the initiation of creatine kinase thermal aggregation.

Protein conformational changes may be associated with particular properties such as its function, transportation, assembly, tendency to aggregate, and potential cytotoxicity. In this research, the conformational change that is responsible for the fast destabilization and aggregation of rabbit muscle creatine kinase (EC 2.7.

Osmophobic effect of glycerol on irreversible thermal denaturation of rabbit creatine kinase.

Protein stability plays an extremely important role not only in its biological function but also in medical science and protein engineering. Osmolytes provide a general method to protect proteins from the unfolding and aggregation induced by extreme environmental stress. In this study, the effect of glycerol on protection of the model enzyme creatine kinase (CK) against heat stress was investigated by a combination of spectroscopic method and thermodynamic analysis.

[A retrospective study on 615 cases of minor salivary gland tumors].

Objective: To analyse the clinical and pathological characteristics of minor salivary gland tumors.

Methods: A retrospective analysis on 615 cases of intraoral minor salivary gland tumors from 1990-2002 with a confirmed pathologic diagnosis was carried out.

Results: In 615 cases of minor salivary gland tumors, 265 cases were benign, 350 cases malignant.

Protein thermal aggregation involves distinct regions: sequential events in the heat-induced unfolding and aggregation of hemoglobin.

Protein thermal aggregation plays a crucial role in protein science and engineering. Despite its biological importance, little is known about the mechanism and pathway(s) involved in the formation of aggregates. In this report, the sequential events occurring during thermal unfolding and aggregation process of hemoglobin were studied by two-dimensional infrared correlation spectroscopy.

Two-dimensional infrared correlation spectroscopy study of sequential events in the heat-induced unfolding and aggregation process of myoglobin.

Unfolding and aggregation are basic problems in protein science with serious biotechnological and medical implications. Probing the sequential events occurring during the unfolding and aggregation process and the relationship between unfolding and aggregation is of particular interest. In this study, two-dimensional infrared (2D IR) correlation spectroscopy was used to study the sequential events and starting temperature dependence of Myoglobin (Mb) thermal transitions.