Biomedical subjects

Y Jiang

Publications and source records attributed to Y Jiang.

711 records · Page 40Linked to original sources

PubMedDate not supplied

Immunohistochemical detection of cytokeratin 18 and its neo-epitope in human salivary glands and pleomorphic adenomas.

An immunohistochemical method using a monoclonal antibody M30 (MAb M30), which reacts with the product released by the cleavage of cytokeratin 18 (CK18) by activated caspase, was used to investigate the extent of apoptosis in human salivary glands and pleomorphic adenomas. The distribution of CK18 in the salivary glands and adenomas was also determined and compared with that of the product detected by MAb M30. CK18 was detected in the cytoplasm of serous acinar and ductal cells in normal human salivary glands. In pleomorphic adenomas, CK18 was observed mainly in the tumor cells of duct-like structures, but not in those of myxomatous or chondroid tissues. Positive MAb M30 reaction products were found in the cytoplasm of acinar cells in the restricted lobules of normal salivary glands and in the luminal contents of duct-like structures in pleomorphic adenomas. These results suggest that a mechanism which suppresses apoptosis may be linked to the growth of human pleomorphic adenomas.

Adenoma, Pleomorphic↗

PubMedDate not supplied

Immunohistochemical detection of cytokeratin 18 and its neo-epitope in Warthin's tumor (adenolymphoma) of the parotid glands.

An immunohistochemical method using a monoclonal antibody M30 (MAb M30), which reacts with the product released by cleavage of cytokeratin 18 (CK18) by activated caspase, was used to investigate the presence and extent of apoptosis in 36 cases of Warthin's tumor (WT) of the parotid glands. The distribution of CK18 in WT was also determined and compared with that of the product detected by MAb M30. In WT, CK18 was observed mainly in the tumor cells of duct-like structures, but not in the cells of lymphatic tissues. Positive MAb M30 reaction products were found in luminal contents, duct-like structures and the cytoplasm of some macrophages in lymphatic areas near the duct-like structures in WT. These findings indicated that apoptotic cells are phagocytosed and eliminated as waste by macrophages. It is suggested that a mechanism which regulates the balance of proliferative activity and apoptosis may be closely linked to the growth of WT.

Adenolymphoma↗

PubMedDate not supplied

Diverse biological activity of polycaphenol.

Millimolar concentrations of alkaline extract of Cacao husk (polycaphenol) were more cytotoxic to human oral tumor cells (human oral squamous cell carcinoma HSC-2, human salivary gland tumor HSG), than to human gingival fibroblast (HGF), suggesting its tumor-specific action. Polycaphenol enhanced the radical intensity and cytotoxic activity of vitamin K3 more effectively than that of sodium ascorbate (vitamin C). Polycaphenol effectively scavenged the superoxide anion, produced by the hypoxanthine-xanthine oxidase reaction, indicating bimodal (prooxidant and antioxidant) action of polycaphenol. Polycaphenol inhibited the cytopathic effect of HIV (human immunodeficiency virus) infection in MT-4 cells, to a comparable extent as that achieved by lignin. Pretreatment of mice with polycaphenol protected them from lethal infection of Eschericia coli. These data suggest the medicinal efficacy of polycaphenol.

Animals↗

PubMedDate not supplied

Molecular epidemiology of infectious bronchitis virus isolates from China and Southeast Asia.

In order to trace the origin and evolution of avian infectious bronchitis virus (IBV) isolates in China and Southeast Asia, genomic sequencing was used for molecular characterization of 24 IBV isolates and two reference strains in comparison with the published sequences. The 5' region of the S1 genes, containing hypervariable regions I and II, and 3' region of the nucleocapsid genes, containing cytotoxic T lymphocyte epitopes, were used to construct phylogenetic trees for analysis. The results showed that the 24 isolates could be divided into three distinct groups, that is, American, Asian, and European. Some isolates formed a distinct Asian phylogenetic group, suggesting that IBV has existed for some time in Asia. Our results also showed that in vivo recombination of IBV may have occurred at a rather high frequency, contributing to the diversity of these IBV isolates. Importantly, recombination events have probably occurred between vaccine strains and field strains in the natural condition.

Animals↗

PubMedDate not supplied

Combination effect of lignin F and natural products.

We investigated the effect of lignin F, isolated from the alkaline extract of the cone of Pinus parviflora Sieb. et Zucc, on the cytotoxic activity and radical intensity (measured by ESR spectroscopy) of various natural products. Lignin F slightly inhibited the proliferation of human oral tumor cell lines (human squamous cell carcinoma HSC-2, human salivary gland tumor HSG), but not that of human gingival fibroblast HGF, suggesting its tumor specific cytotoxic action. Lignin F enhanced the cytotoxic activity of vitamin K2, vitamin K3, sodium ascorbate (vitamin C), epigallocatechin gallate (EGCG) (a major component of green tea), gallic acid (structural unit of tannin), chlorogenic acid, and 6 tea extracts (Japanese green tea, Japanese barley tea, black tea, Chinese green tea, Chinese Jasmin tea, Chinese Oolong tea), to various extents. On the other hand, lignin inhibited the cytotoxic activity of curcumin and dopamine. ESR spectroscopy demonstrated that combination of lignin and vitamin K3, EGCG or gallic acid synergistically augmented the radical intensity. Lignin F enhanced the bactericidal activity of EGCG against E. coli. These data suggest the beneficial effect of the combination of lignin F and natural products.

Antineoplastic Agents, Phytogenic↗

PubMedDate not supplied

Characterization of three infectious bronchitis virus isolates from China associated with proventriculus in vaccinated chickens.

Outbreaks of an avian disease in infectious bronchitis-vaccinated chickens in China have led to the characterization of coronaviral isolates Q1, J2, and T3, which were isolated from proventricular tissues of the affected young layer flocks. Serologic analysis revealed that they could induce high titers of infectious bronchitis virus (IBV) antibodies in inoculated specific-pathogen-free (SPF) chickens in indirect enzyme-linked immunosorbent assay but were not neutralized by antisera specific to the IBV serotype M41 and the Australian T strain. In a pathogenicity experiment, the clinical signs and related gross lesions resembling those of field outbreaks were reproduced in SPF chickens, and viruses were reisolated from the damaged tissues, including trachea, proventriculus, duodenum, and cecal tonsil. Sequence data demonstrated the complete S1 amino acid sequences of these isolates were almost identical despite recovery from geographically different areas in China and had 47.3%-82.3% similarity in comparison with the 47 published S1 sequences. On the basis of genotyping and limited serology, the three isolates, which were responsible for field outbreaks of the disease, might be a new IBV variant.

Animals↗

PubMedDate not supplied

Inhibition of chlorogenic acid-induced cytotoxicity by CoCl2.

Chlorogenic acid (CGA) induced apoptotic cell death in human oral squamous cell carcinoma (HSC-2) and salivary gland tumor (HSG) cell lines. CGA exhibited oxidation potential in the culture medium, as demonstrated by NO monitor. Both cytotoxic activity and oxidation potential were significantly reduced by the addition of CoCl2. ESR spectroscopy showed that CGA produced seven peaks of radicals under alkaline condition, while addition of CoCl2 altered the spectral pattern and diminished the radical intensity of CGA. CoCl2 accelerated the CGA-induced coloration of the culture medium and modified the difference spectrum at around 325 nm, an absorption maximum characteristic of CGA. These data suggest that CoCl2 induced conformational changes in the CGA molecule.

Carcinoma, Squamous Cell↗

PubMedDate not supplied

Synergistic cytotoxic action of vitamin C and vitamin K3.

We investigated the combination effect of sodium ascorbate (vitamin C) and menadione (vitamin K3) on the viability of various cultured cells. Human oral squamous cell carcinoma (HSC-2, HSC-3) and human promyelocytic leukemia (HL-60) cells were more sensitive to these vitamins as compared to normal cells (human gingival fibroblast HGF, human periodontal ligament fibroblast HPLF, human pulp cell HPC). The combination of vitamin C and vitamin K3 produced synergistic cytotoxicity against all these 6 cell lines. Treatment with vitamin C or vitamin K3, or their combination, induced internucleosomal DNA fragmentation only in HL-60 cells, but not in the oral tumor cell lines (HSC-2, HSC-3, HSG). ESR spectroscopy showed that vitamins C and K3 produce radicals under alkaline conditions and that the combination of these two vitamins synergistically enhanced their respective radical intensities.

Antineoplastic Combined Chemotherapy Protocols↗

PubMedDate not supplied

Treatment of urgency and urge incontinence with flavoxate in the People's Republic of China.

Flavoxate is a smooth muscle relaxant widely used to treat urgency and urge incontinence. It has been used in an unblinded, uncontrolled clinical trial in 14 urology departments in universities and major hospitals in the People's Republic of China involving 361 patients with urgency/incontinence of various types. Patients were given 200 mg three times daily, orally, for 2 weeks, although 33 patients received a daily dosage of 1200 mg. Frequency, urgency, dysuria, nocturia and incontinence were assessed and scored clinically prior to and after treatment. Three departments also included urodynamic investigations, e.g. monitoring of the end-residual volume. Results from 336 evaluable patients indicate that 228 (67%) were completely cured of urgency/incontinence symptoms, 66 (20%) were improved and 42 (13%) patients were unchanged. Flavoxate was also effective in 77.4% of patients refractory to previous anti-cholinergic treatment. Treatment did not increase the end-residual volume and adverse events occurred only in four (1.3%) patients, two (0.6%) of which discontinued the therapy. The 1200 mg dose produced a complete cure in 82% of patients and improvement in the remaining 18%, with no side-effects. In conclusion, flavoxate is an effective and well tolerated treatment for urgency/incontinence of various causes.

Adolescent↗