Search PubMed⌕ Search

Biomedical subjects

F Deng

Publications and source records attributed to F Deng.

At least 37 records · Page 2Linked to original sources
PubMed1999

[Study on bacterial strains in conjunctival sac before and after intraocular surgery].

PURPOSE: To investigate the changes of bacterial strains in the conjunctival sac before and after intraocular surgery, as well as clinical effects of preoperative antibiotic agents. METHODS: One hundred and thirty-three eyes with intraocular surgery included 68 eyes with cataract surgery, 39 eyes with glaucoma surgery, 20 eyes with retinal detachment surgery and 6 eyes with vitretomy. Bacterial culture and pharmacologic sensitivity test were performed on the conjunctival smear from the 133 eyes with intraocular surgery before and after the operation and the anterior chamber aspirate from the 68 eyes with cataract surgery after the operation. RESULTS: At the time of admission, 61 eyes(45.8%) of 133 eyes with intraocular surgery were culture-positive conjunctival smears with the following identified: Staphlococcus aureus: 23 eyes; Staphlococcus epidermidis: 25 eyes; Gram-positive rods: 13 eyes. 8 eyes(6%) had culture-positive conjunctival smears before disinfection, (Staphlococcus aureus: 3 eyes; Staphlococcus epidermidis: 5 eyes). One eye(1.5%) had culture-positive Staphylococcus epidermidis in anterior chamber aspirate of 68 eyes with cataract surgery at conclusion of surgery. Also, 4 eyes(3%) were culture-positive conjunctival smears after surgery. All the bacterial strains of the group were sensitive to Tobramycin, Gentamycin, Cephradinum(Velosel), Vancomycinum and Rifampin, but they were resistance to Tetracyclinum, Chloromycetin, Erythromycin and Ofloxacin. Eye Science 1999; 15: 267-269. CONCLUSION: In order to prevent bacterial endophthalmitis after intraocular surgery, installation of an useful antibiotic eye drop before the surgery is important.

Adult↗
PubMed1998

1H/27Al TRAPDOR NMR studies on aluminum species in dealuminated zeolites.

Aluminum species in several dealuminated zeolites (ultrastable HY, HZSM-5 and mordenite) were investigated in detail by means of the newly introduced 1H/27Al TRAPDOR method in combination with 27Al MAS NMR, and the quadrupole coupling constants (Q[CC]s) for aluminum atoms associated with these species were obtained. A signal at ca. 6.8 ppm, due to water molecules adsorbed on Lewis acid sites, was observed in the 1H MAS spectra for all the three zeolites. The TRAPDOR NMR provides direct evidence that there is a strong interaction between the adsorbed water molecules and the aluminum atoms of the Lewis-acid sites. The Q(CC) values for this aluminum species of 8.3, 6.7 and 11.3 MHz were determined from the TRAPDOR profiles for the ultrastable HY, HZSM-5 and mordenite zeolites, respectively. The Q(CC)s calculated from the TRAPDOR curves are usually larger than 10 MHz for both Bronsted-acid sites (SiOHAI) and non-framework aluminum species in the three zeolites. Three narrow peaks at 54, 30 and 0 ppm are separately superimposed on a broad hump in the 27Al MAS spectra of the three dehydrated zeolites, while the latter is associated with the 'NMR invisible' Al. The NMR experimental results suggest that the three kinds of aluminum species (non-framework aluminum species, Bronsted- and Lewis-acid sites) are all responsible for the resonance of the broad hump in dehydrated zeolites, which makes it difficult to explain the 27Al MAS spectra. Fortunately, the TRAPDOR NMR provides a direct method for individually studying different aluminum species with large Q(CC)s via their dipolar coupling to nearby proton nuclei.

Aluminum↗
PubMed1998

EGFR antisense RNA blocks expression of the epidermal growth factor receptor and partially reverse the malignant phenotype of human breast cancer MDA-MB-231 cells.

The effects of human EGFR to the malignant phenotype of human breast cancer cell line MDA-MB-231 were investigated experimentally. A retroviral vector containing a 5'1350bp fragment of the human EGFR cDNA in the antisense orientation was transfected into targeted cells by lipofectamine. The effects on cell proliferation, cell cycle and adherent ability to extracellular matrix (ECM) components were studied after the expression of antisense transcripts to EGFR 5'1350bp fragment in target cells. In vitro studies showed that the growth ability of the transfected cells was partially inhibited in comparison to parental cells and to cells transfected with the plasmid containing the neomycin resistance gene only. It was found that EGF (10 ng/ml) had an argumenation effect on the growth of transfected MDA-AS10 cells but not MDA-MB-231 cells. Flow cytometric analysis showed that the cell cycle of the transfected cells was abnormal with a decrease of cells in G2/M and S phases and an increase of cells in G1 phase, indicating a blockage in phase G1. Immunofluorescence of EGFR expression in transfectants stained with an anti-EGFR antibody was decreased and their growth in soft agarose was also severely impaired. The transfected cells showed less adherence to laminin (LN) and fibronectin (FN). In short, EGFR antisense RNA decreases the expression of EGFR on MDA-MB-231 cells and partially reverses their malignant phenotype as well.

Breast Neoplasms↗
PubMed1998

Downstream technique study of human tumor necrosis factor alpha and its mutant.

The study of downstream techniques for recombinant human necrosis factor alpha (rhTNF alpha) and its mutant (Lys2)-rhTNF alpha led to the results of approximately 50 g wet recombinant E. coli per liter with high expression level (> 50%) harvested from autocontrolled fed-batch culture in 15 L fermentor (B. Braun). The rhTNF alpha and (Lys2)-rhTNF alpha expressed are totally soluble. Followed by the process of ultrasonication, ammonium sulfate precipitation, ion-exchange chromatography (DEAE-sepharose FF, CM-sepharose FF), and molecular sieve (Sephacryl S-200), a yield of approximately 1 g pure recombinant protein from 1 L broth is obtained. The purity is up to 98%. The specific activity of rhTNF alpha and (Lys2)-rhTNF alpha are approximately 1.5 x 10(8) IU/mg and approximately 6 x 10(8) IU/mg, respectively.

Escherichia coli↗
PubMed1998

[Analysis of amino acids, vitamins and inorganic elements in Dictyophora indusiata].

Fifteen amino acids(total content: 13.37 mg.100 ml-1), 12 inorganic elements(Zn 37.3 micrograms.g-1, Mn 56.9 micrograms.g-1, Cr 4.88 micrograms.g-1, Fe 370 micrograms.g-1, Se 0.81 microgram.g-1, Cu 28.2 micrograms.g-1, Co 0.78 microgram.g-1, Ni 2.09 micrograms.g-1, etc.), and vitamin E(73.2 micrograms.g-1) in Dictyophora indusiata were determined. Seven amino acids, including valine 0.61, leucine 1.04, isoleucine 0.66, threonine 0.74, methionine 0.20, lysine 0.52, and pheuylalanine 0.64(mg.100 mg-1), were found to be essential. The possible medical significance of Dictyophora indusiata is discussed.

Amino Acids↗
PubMed1998

[Hodgkin's disease: Ig gene rearrangements in single H/R-s cells].

OBJECTIVE: To investigate the origin and cell lineage of Hodgkin/Reed-Sternberg (H/R-S) cells from various subtypes of Hodgkin's disease (HD). METHODS: 68 single H/R-S cells were taken from frozen section of 8 cases of HD. The DNA from these single cells was amplified by polymerase chain reaction (PCR) with immunoglobulin heavy chain gene FR III a/JH primers and light chain family-specific primers. RESULTS: (1) IgH and V kappa 4 rearrangements were repeatedly found in H/R-S cells from one case of lymphocytic predominant HD (LPHD). (2) Repeated and unique IgH and V kappa 2,4 rearrangements were observed in 1 case of nodular sclerosing HD (NSHD) and unique IgH, V lambda 3/V kappa 4 rearrangements in another case of NSHD. (3) Repeated IgH/V lambda 3 and unique V lambda 2,4 rearrangements, repeated V kappa 4 and unique IgH/V kappa 3 rearrangements, plus repeated IgH and unique V kappa 3/V lambda 4 rearrangements were detected respectively in 3 cases of mixed cellularity HD (MCHD). Repeated and unique rearrangements were found respectively in 2 cases of MCHD. CONCLUSIONS: The H/R-S cells isolated from LPHD had monoclonal Igh and V kappa 4 gene rearrangements, which supports the conclusion that LPHD is a monoclonal proliferation of B cells. The appearance of IgH and kappa, lambda gene rearrangement suggest that the H/R-S cells isolated from classical HD (MCHD and NSHD) originate from B lineage cells at various stages of differentiation.

Gene Rearrangement, B-Lymphocyte, Light Chain↗
PubMed1998

[A monoclonal antibody that reacts with an antigen on both normal and malignant prostate cells].

OBJECTIVE: To study the YDPC--a monoclonal antibody that reacts with an antigen on both normal and malignant prostate cell. METHOD: A murine monoclonal antibody (MAb) designated YDPC was generated by treating the primed spleen cells with leucine methyl ester (LeuOMe) following immunization of mice with prostate cancer cell line PC-3M. RESULT: YDPC reacted uniformly with all adenocarcinomas of the prostate examined. It also reacted with the surface antigen on normal prostate epithelial cells and on cells from benign prostate hyperplasia. YDPC reacted with a limited number of normal tissues including renal tubules, adrenal and sweat gland. In addition, three lymph nodes metastasis and one bladder metastasis were found to be strongly positive, while four transitional cell carcinomas of the prostate negative. Preliminary experiments showed that this antibody does specifically localize to prostate cancer xenografts in nude mice. CONCLUSION: YDPC reacts with a differentiation antigen and this antigen continues to be expressed on all adenocarcinomas of the prostate. This antibody may be useful in the diagnosis of or therapy for prostate cancer.

Adenocarcinoma↗
PubMed1998

[Studies on the liquid-liquid extraction behaviour of Co(II) and Ni(II) without organic solvents].

In PEG-Eriochrome cyanine R-(NH4)2SO4 system the liquid-liquid extraction behaviour of Co(II) and Ni(II) without organic solvents was investigated. We found that Ni(II) was almost extracted by PEG phase while Co(II) was not extracted in the water solutions of NaAc-HAc (pH=5) and (NH4)2SO4. Thus Co(II) was quantitatively separated from mixed solutions of Ni(II) and Co(II) ions.

English Abstract↗
PubMed1997

1H MAS and 1H[23Na] double resonance NMR studies on the modification of surface hydroxyl groups of gamma-alumina by sodium.

The modification of surface hydroxyl groups with sodium in a series of Na2CO3-gamma-Al2O3 catalysts was investigated as a function of both the Na2CO3 loading and the calcination temperature by means of 1H magic angle spinning (MAS) and 1H(23Na) spin-echo double resonance NMR techniques. The 1H NMR experiments revealed that sodium ions are homogeneously distributed over the alumina surface and closely coordinated with the surface hydroxyl groups. In the catalysts calcined at 250 degrees C, the acidic hydroxyl groups (with a chemical shift of 2.0 ppm) are preferentially associated with sodium ions at low Na2CO3 coverages (5 and 10%), while both the acidic and the basic (0 ppm) hydroxyl groups are accessible for sodium ions at high coverages (15 and 20%). The coordination causes a low-field shift of about 2 ppm in the 1H MAS spectra, and a broad signal at 4.5 ppm appears. It is interesting that the 4.5 ppm signal is completely suppressed in the 1H(23Na) MAS experiments, providing direct evidence that a strong interaction exists between adsorbed sodium ions and the surface hydroxyl groups. Increasing the calcination temperature to 450 degrees C results in preferential removal of the acidic hydroxyl groups, and only the most basic hydroxyl groups remain when the calcination temperature is raised to 600 degrees C. This is attributed to the formation of the coordinated species. [formula: see text] which enhances the acidity of the surface hydroxyl groups and prompts their dehydroxylation, especially at high calcination temperature. Correlation of the 1H MAS NMR results and catalytic activity measurements indicates that the basic hydroxyl groups are essential for the carbonyl sulfide hydrolysis reaction.

Aluminum Oxide↗
PubMed1997

[Hemolysis of Scolopendra toxins].

The hemolysis of toxins from alive Scolopendra subspinipes mutilans, medicinal material of Scolopendra subspimipes mutilans and S. multidens have been compared. The result shows that all the toxins have hemolytic activity. The hemolytic activity of the toxin from the medicinal materials of S. subspinipes mutilans is obviously lower than that from alive ones, and that from fresh medicinal materials are twice as high that from old ones, and that from S. multidens is higher than that from S. subspinipes multilans.

Animals↗
PubMed1997

[A study of anaerobic infection in maxillofacial region].

To analyse the anaerobic infection of maxillofacial surgery and estimate the efficacy of antianaerobic therapy, 45 patients were divided into two groups, tinidazole group and metronidazole group. Bacterial culture was positive before treating in all cases. There were Bacillus Melaniogenicus, Veillonella, Peptococcus and Peptostreptococus, etc. There was excellent efficacy in the treatment of maxillofacial anaerobic infection by tinidazole intravenously. After treatment, the result of bacterial examination was negative. The healing rate was 96.4% in 28 cases which used tinidazol, but 82.4% in control group which used metronidazole. The value of white blood cell and the function of liver and kidney pro- and post-treatment were not significantly different (P < 0.05) by comparision.

Adolescent↗
PubMed1996

High resolution 1H spectra of powdered solids observed by Hahn echo pulse sequence with magic-angle spinning.

The 1H magic-angle spinning (MAS) spectrum for a typical powdered solid is composed of a high resolution component and a broadline component. The high resolution component can be well isolated from the broadline component by the Hahn echo sequence with a long echo time. Compared with CRAMPS experiment, which measures the proton system as a whole, the high resolution echo-MAS method measures only a fraction of the solid, which is usually small at room temperature and quite different from the majority of the solid in both molecular motion and chemical environment. It is shown that for a sample of fumaric acid monoethyl ester, the chemical shifts of the high resolution component are apparently distinguishable from the isotropic chemical shifts of the broadline component in the CRAMPS spectrum as the temperature approaches the melting point. In addition, for a sample of malonic acid, the echo-MAS spectrum is sensitive to moisture and temperature, while its corresponding CRAMPS spectrum is not. It is suggested that the molecules which produce the high resolution component are related to the lattice defects in a solid, including the surface disorder of the polycrystallites, while the molecules that generate the broadline component are located on the rigid lattice of the solid.

Chemical Phenomena↗
PubMed1996

Solid-state NMR investigation of acid sites in dealuminated HZSM-5 zeolite.

The acid sites and the hydration behaviors of dealuminated HZSM-5 zeolites (calcined at 550, 600, 650, and 700 degrees C) were characterized by high-resolution 1H MAS, 1H{27A1} spin-echo double resonance in combination with 27A1 MAS NMR. Apart from the usually observed peaks for dealuminated zeolite HZSM-5, a narrow plus a broad peak simultaneously appears at ca. 6.9 ppm in the 1H spectra and they exhibit different decay behavior in the 1H [27A1] double-resonance experiments. The existence of the former signal indicates that Lewis acid sites may'be formed in the zeolites after calcination. By means of the spin echo double resonance technique, we observed for the first time a previously unexpected narrow signal at 5.2 ppm, which resonates on the downfield side of Bronsted acid signal (4.3 ppm) and cannot be resolved in the 1H MAS spectra. This new signal is probably due to another kind of Bronsted acid site, locating in the small cages bounded by four- and five-membered rings. Three narrow peaks at 50 ppm, 30 ppm, and 0 ppm are superimposed on a very broad signal in the 27A1 MAS NMR spectra of dried HZSM-5. The intensity of the line at 50 ppm is significantly reduced compared with that of the rehydrated sample. 27A1 MAS NMR suggests that most part of the four-coordinated framework A1 turns into a intermediate case between four- and three-coordinated A1 after the dehydration and this process is reversible upon dehydration/rehydration. While some framework A1 atoms are transformed into three-coordinated A1 species and Lewis acid sites are, thus, generated in the dealuminated zeolites. For the signal at 30 ppm, the hydration leads to a dispersion in the chemical shift or the quadrupole interaction, which broadens its linewidth in hydrated samples.

Magnetic Resonance Spectroscopy↗
PubMed1996

[The application of high molecular weight cytokeratin in differential diagnosis of prostate adenocarcinoma].

In order to understand the characteristics of proliferative and malignant prostate lesions and to improve the differential diagnosis, immunohistochemical methods using high molecular weight cytokeratin monoclonal antibody 34BE12 to stain the basal cells and to differentiate prostate cancer from hyperplasia in 82 prostate biopsies and specimens, which included 21 adenocarcinoma, 30 intraepithelial neoplasia, 5 atypical adenomatous hyperplasia, 8 basal cell hyperplasia, 11 atrophy of prostate, 4 postatrophic hyperplasia and 3 cribriform hyperplasia. It was demonstrated that the basal cell layer was lost in all prostate adenocarcinomas, but existed in most of the proliferative lesions except for atypical adenomatous hyperplasia and grade 3 intra-epithelial neoplasia in which the basal layer was disrupted in some cases. The study showed that the 34BE12 antibody was useful in the differential diagnosis of prostate adenocarcinoma.

Adenocarcinoma↗
PubMed1996

[Proliferation and apoptosis status in benign prostatic hyperplasia].

The aim of this study was to examine the proliferation and apoptosis status in normal prostate and benign prostatic hyperplasia. The proliferation status was evaluated by using monoclonal antibodies which recognize the proliferating cell nuclear antigen and the proliferating associated nuclear antigen Ki67. The apoptosis status was detected by in situ end-labeling of fragmented DNA using the terminal deoxynucleotidyl transferase reaction. A total of 22 cases benign prostatic hyperplasia and 20 cases of normal protate specimens were studied. The proliferation index of BPH was much higher than that of normal prostates, and the apoptosis index of hyperplasia epithelium was much lower than that of normal prostatic epithelium. The results suggest that both high proliferating rate and low apoptosis rate are associated with the pathogenesis of benign prostatic hyperplasia.

Antibodies, Monoclonal↗
PubMed1996

[Expression of basic fibroblast growth factor and its receptor in renal cell carcinoma].

Basic fibroblast growth factor (bFGF) is a pluripotent polypeptide which plays an important role in tumor progression and angiogensis. We determined the expression and localization patterns of bFGF and one of its receptor (FGFR-1) in normal renal as well as in renal cancers. The results were compared with clinicopathologic features. Using bFGF and FGFR-1 antibody, the repairing method of antigen with microwave oven heating and LSAB immunohistochemistry we used in 36 cases of paraffin-embedded renal cell carcinoma (RCC) and their paired normal renal tissues. The expression of bFGF and FGFR-1 was nearly consistent. The normal renal tissues and ECM of 29 cases of renal cancer tissues showed heterogenous immunoreactivities. Renal cancer cell cytoplasm of 12 primary tumors and 2 metastatic tumors, as in the cytoplasmic bFGF of cultured GRC-1 cells, were positively homogenous stained. The bFGF and FGFR-1 can be consistently expressed in normal renal and renal cancer tissues, reflecting that the expression and function of these substances were closely associated. The cytoplasmic bFGF expression of renal cancer was related to tumor stages, suggesting that b bFGF plays an important role in the progression of renal cell carcinoma.

Adenocarcinoma, Clear Cell↗
PubMed1996

[In situ hybridization to detect the mRNA for insulin-like growth factor-I and II in the prostate].

In order to well understand the expression of mRNA for insulin-like growth factor I and II in normal and hyperplastic prostate, in situ hybridization were used to detect them in a total of 35 cases of prostate. Both the normal and the hyperplastic prostate expressed the mRNA for IGF-I/II. The mRNA for IGF-I was mainly expressed by the epithelial cells and the IGF-II was mainly expressed by the stromal cells. The hyperplastic tissues expressed higher levels of the mRNA for IGF-I and IGF-II. The results suggested that the IGF might play an important role in the regulation of prostate growth and the pathogenesis of benign prostatic hyperplasia.

Adolescent↗