Biomedical subjects

Y Lü

Publications and source records attributed to Y Lü.

34 records · Page 2Linked to original sources

PubMed1998

[The influence of pressure on human lamina cribrosa cell and its collagen synthesis].

OBJECTIVE: To study the influence of pressure on human lamina cribrosa cell (HLC) and its synthesis of collagen. METHOD: HLCs were cultured in vitro and submitted to elevated hydrostatic pressure, their changes in morphology were observed by light and electron microscopy and their synthesis of collagen was measured with fluorescence spectrophotometer. RESULTS: Under a hydrostatic pressure of 6.67 kPa (1 kPa = 7.5 mmHg), the flat and polygonal HLCs became elongated. Vacuoles appeared in the cytoplasm and increased as the pressure persisted. The mitochondria were swollen, some of them turned into vacuoles, and myelin figures were found in the cytoplasm. When exposed to elevated pressure for 3 days, the amounts of synthesized collagen type I, III, IV were 43.95 +/- 6.37, 61.35 +/- 10.35 and 82.90 +/- 11.36 arbitrary unit (AU) by fluorometry respectively, and compared to controls, they were statistically significantly (P < 0.05) increased; after 5 days of pressure exposure, the amounts were 33.50 +/- 6.94, 40.85 +/- 12.30 and 80.45 +/- 14.65 AU, e.g., still increased. CONCLUSION: It is indicated that under pressure, HLCs undergo obvious morphological changes and increase their synthesis of collagen types I, III and IV.

Collagen↗

PubMed1998

[A preliminary observation on vitrectomy combined with autologous platelet concentrate for the treatment of idiopathic macular holes].

OBJECTIVE: To investigate the efficacy of vitrectomy combined with autologous platelet concentrate for the treatment of idiopathic macular holes. METHODS: Fifteen eyes of 14 patients with idiopathic macular hole were treated. The follow-up period ranged from 3 to 16 months. Postoperatively, visual acuity, macular threshold, Amsler grid, fluorescein angiography (FA) and complications were evaluated. RESULTS: Of the fifteen eyes, the closure of the holes was achieved in 13 eyes (86.7%), visual acuity improved for two lines or more in 12 eyes (80.0%). The postoperative visual acuities in patients with abnormal Amsler grid were improved. No significant differences were found in the macular threshold (P = 0.34). Postoperative FA showed that the blocked fluorescence at the site of the macular hole which was surrounded by a hyperfluorescence ring (window defect) in three eyes. The intraoperative complication was primarily the retinal hole, and the postoperative complication was chiefly the aggravation of cataract. CONCLUSIONS: These results indicate that vitrectomy combined with autologous platelet concentrate can seal the macular hole well and improve the visual acuity in most patients. A large multicenter randomized prospective study and a longer period of follow-up are needed to verify these results.

Blood Transfusion, Autologous↗

PubMed1997

[Numerical change of 7, 17 and Y chromosomes in human lung carcinoma detected by fluorescence in situ hybridization].

OBJECTIVE: To study the copy number of chromsomes 7,17 and Y in lung carcinomas. METHODS: Fluorescence in situ hybridization (FISH) was used to detect the number of above mentioned chromosomes on the touch smears of 17 cases of lung carcinoma (adenocarcinoma and squamous cell carcinoma). RESULTS: Triploid chromosome 7 FISH signals were found in 31.73% of the tumor nuclei, dipoid chromosome 17 FISH signals in 43.00% and monoploid chromosome Y FISH signals in 58.04% of these nuclei. CONCLUSIONS: The number of chromosome 7 was obviously increased in both lung adenocarcinoma and squamous cell carcinoma, and the rate of trisomy 7 was the highest. In addition, there is a significant difference in the distribution of chromosome 7 ploidy between lung adenocarcinoma and squamous cell carcinoma.

Adenocarcinoma↗

PubMed1997

[Chromosome marker--2q- during carcinogenesis and development of human lung cancer].

OBJECTIVE: To study the cytogengtic alterations during the development of human lung cancer and to clarify the genetic basis of lung cancer. METHODS: Using Fluorescence in situ Hybridization FISH, we have studied the chromosomal alterations of chromosome 2 and 3 in human bronchial epithelial cell line M, and 12 primary non-small cell lung cancer (NSCLC) specimens. RESULTS: 2q- was found in the later passage of human bronchial epithelial cell line M, and 3 out of 7 primary NSCLC specimens tested. 3p- being noted in five cases of 12 primary NSCLC patients examined was the first cytogenetic discovery and the most prominent abnormality in lung cancer. 2q- was rarely reported in human lung cancer before. But loss of heterozygosity by RFLP analysis for 2q had been reported in lung cancer. CONCLUSION: 2q- is also a common chromosome abnormality in human lung cancer. There would also be one or more putative tumor suppressor gene(s) on the long arm of chromosome 2. Loss of the gene(s) may contribute to the carcinogenesis of human non-small-cell lung cancer.

Adenocarcinoma↗

PubMed1997

Coexistence of mu-opioid receptor-like and substance P-like immunoreactivities in the cat dorsal root ganglionic neurons.

Coexistence of mu-opioid receptor (MOR)-like immunoreactivity (LI) and substance P (SP)-LI in the neurons of the cat dorsal root ganglia (DRG) was examined by a double immunofluorescence histochemical method. Approximately 91% of SP-LI neurons in the DRG showed MOR-LI. However, SP-LI was exhibited in approximately 28% of the neurons labeled with MOR-LI. These morphological findings indicated that the MOR exist on most of the primary afferent SP-containing terminals, and suggest that MOR may regulate SP release from the primary afferent terminals in the cat dorsal horn.

Afferent Pathways↗

PubMed1996

Synthesis and structure-activity relationships of 1,2,3,4-tetrahydroquinoline-2,3,4-trione 3-oximes: novel and highly potent antagonists for NMDA receptor glycine site.

A series of 1,2,3,4-tetrahydroquinoline-2,3,4-trione 3-oximes (QTOs) was synthesized and evaluated for antagonism of NMDA receptor glycine site. Glycine site affinity was determined using a [3H]DCKA binding assay in rat brain membranes and electrophysiologically in Xenopus oocytes expressing 1a/2C subunits of cloned rat NMDA receptors. Selected compounds were also assayed for antagonism of AMPA receptors in Xenopus oocytes expressing rat brain poly-(A)+RNA. QTOs were prepared by nitrosation of 2,4-quinolinediols. Structure-activity studies indicated that substitutions in the 5-, 6-, and 7-positions increase potency, whereas substitution in the 8-position causes a decrease in potency. Among the derivatives evaluated, 5,6,7-trichloro-QTO was the most potent antagonist with an IC50 of 7 nM in the [3H]DCKA binding assay and a Kb of 1-2 nM for NMDA receptors expressed in Xenopus oocytes. 5,6,7-Trichloro-QTO also had a Kb of 180 nM for AMPA receptors in electrophysiological assays. The SAR of QTOs was compared with the SAR of 1,4-dihydroquinoxaline-2,3-diones (QXs). For compounds with the same benzene ring substitution pattern, QTOs were generally 5-10 times more potent than the corresponding QXs. QTOs represent a new class of inhibitors of the NMDA receptor which, when appropriately substituted, are among the most potent glycine site antagonists known.

Animals↗

PubMed1996

[The overexpression of c-met oncogene correlation with gastric mucosal lesion].

OBJECTIVE: To determine whether there is a relationship between overexpression of c-met oncoprotein and stage of human gastric mucosal lesions, and its significance. METHOD: Immunohistochemical staining was used in 157 cases of endoscopic biopsies with c-met monoclonal antibody, S-19, which was raised against the human c-met gene product. RESULTS: overexpresion of c-met oncoprotein was detected in 3/30 cases (10%) of superficial gastritis, 4/33 cases (12.1%) of chronic atrophic gastritis, 10/31 cases (32.3%) of intestinal mataplasia, 10/30 cases (33.3%) of dysplasia, and 10/30 cases (33.3%) of gastric carcinoma. The positive staining rate was higher in intestinal mataplasia (54.8%), dysplasia (56.7%), carcinoma (53.3%) than in two kinds of simple chronic gastritis (P < 0.05). The positive staining was obviously located in luminal membrane of mucosal cells. The positive cells were mainly situated in proliferative cell zone of gastric glands. Moreover, the weak staining only in this zone was shown in two of the three normal mucosa. CONCLUSIONS: The overexpression of c-met may be involved in proliferation of gastric mucosa. It is possible that persistent overexpression of c-met oncoprotein is associated with the malignant transformation of gastric mucosal cells.

Adenocarcinoma↗

PubMed1996

[A study of 5-fluorouracil on bovine trabecular meshwork cells in vitro].

OBJECTIVE: To determine whether the clinical use of 5-fluorouracil (5-FU) may have any toxic effects on trabecular meshwork cells. METHODS: Bovine trabecular meshwork (BTM) cells were cultured in vitro. The effects of 5-FU on BTM cells concerning cellular morphology, ultrastructure, vitality and phagocytosis were observed. RESULT: The safe dosage of 5-FU on BTM cell was 1 x 10-6g.ml-1. CONCLUSION: Based on the pharmacokinetic data in the rabbit anterior chamber, it is suggested that the 5-FU dosage of conventional use cause no injury to human trabecular meshwork cells.

Animals↗

PubMed1995

Synthesis and structure-activity relationships of substituted 1,4-dihydroquinoxaline-2,3-diones: antagonists of N-methyl-D-aspartate (NMDA) receptor glycine sites and non-NMDA glutamate receptors.

A series of mono-, di-, tri-, and tetrasubstituted 1,4-dihydroquinoxaline-2,3-diones (QXs) were synthesized and evaluated as antagonists at N-methyl-D-aspartate (NMDA)/glycine sites and alpha-amino-3-hydroxy-5-methylisoxazole-4-propionic acid-preferring non-NMDA receptors. Antagonist potencies were measured by electrical assays in Xenopus oocytes expressing rat whole brain poly(A)+ RNA. Trisubstituted QXs 17a (ACEA 1021), 17b (ACEA 1031), 24a, and 27, containing a nitro group in the 5 position and halogen in the 6 and 7 positions, displayed high potency (Kb approximately 6-8 nM) at the glycine site, moderate potency at non-NMDA receptors (Kb = 0.9-1.5 microM), and the highest (120-250-fold) selectivity in favor of glycine site antagonism over non-NMDA receptors. Tetrasubstituted QXs 17d,e were more than 100-fold weaker glycine site antagonists than the corresponding trisubstituted QXs with F being better tolerated than Cl as a substituent at the 8 position. Di- and monosubstituted QXs showed progressively weaker antagonism compared to trisubstituted analogues. For example, removal of the 5-nitro group of 17a results in a approximately 100-fold decrease in potency (10a,b,z), while removal of both halogens from 17a results in a approximately 3000-fold decrease in potency (10v). In terms of steady-state inhibition, most QX substitution patterns favor antagonism at NMDA/glycine sites over antagonism at non-NMDA receptors. Among the QXs tested, only 17i was slightly selective for non-NMDA receptors.

Animals↗

PubMed1995

Expression of c-fos protein in substance P receptor-like immunoreactive neurons in response to noxious stimuli on the urinary bladder: an observation in the lumbosacral cord segments of the rat.

Chemical irritation of the urinary bladder with formalin in the rat induced c-fos protein-like immunoreactivity in more than 80% of substance P receptor-like immunoreactive (SPR-LI) neurons of the dorsal commissural nucleus, sacral parasympathetic nucleus and lamina I in the 6th lumbar and 1st sacral cord segments. These neurons with SPR-LI may receive noxious information from the urinary bladder through the primary afferent fibers with substance P.

Animals↗

PubMed1995

[Detecting human papillomavirus DNA of condylomata and pseudo-condylomata by in situ hybridization and polymerase chain reaction in paraffin-embedded specimens].

One hundred and thirty seven cases of paraffin-embedded tissue specimens biopsied each from condylomata and pseudo-condylomata of vulva and vagina were examined. Type 6b 11 human papillomavirus (HPV) DNA was detected in condylomata by in situ hybridization using digoxigeninlabelled probes and polymerase chain reaction (PCR). The positive rate was 82.5%, 83.9% respectively. It was negative in the 137 cases of pseudo-condylomata by in situ hybridization, but positive in 3 cases by PCR. For a correct diagnosis, the necessity of combining the data of clinical finding, microscopic examination and in situ hybridization or PCR is emphasized. Our results showed that pseudo-condylomata represent dysplastic appearances of vulval and vaginal mucosa, which become more marked during pregnancy and fungal or trichomonal infections, and could rather easily be misdiagnosed as condylomata.

Condylomata Acuminata↗

PubMed1995

Stable oncogenic transformation induced by microcell-mediated gene transfer.

Oncogenes have been identified using DNA-mediated transfection, but the size of the transferable and unrearranged DNA, gene rearrangement and amplification which occur during the transfection process limit the use of the techniques. We have evaluated microcell-mediated gene transfer techniques for the transfer and analysis of dominant oncogenes. MNNG-HOS, a transformed human cell line which contained the met oncogene mapping to human chromosome 7 was infected with retroviruses carrying drug resistance markers and used to optimize microcell preparation and transfer. Stable and drug-resistant hybrids containing single human chromosomes as well as the foci of the transformed cells containing the activated met oncogene and intact human chromosomes were obtained. Hybridization analysis with probes (i.e. col1A2, pJ3.11) mapping up to 1 Mb away from met shows that the cells from the individual foci contain different amounts of apparently unrearranged human DNA associated with the oncogene, and the microcell-generated transformants retain more distal markers than those observed in either DNA- or chromosome-mediated transfers. In conjunction with other techniques, microcell fusion should be useful for gene mapping as well as the study of gene function and expression in cell transformation and malignancy.

3T3 Cells↗

PubMed1994

The distribution and origin of axon terminals with NADPH diaphorase activity in the nucleus of the solitary tract of the rat.

The distribution and origin of axon terminals containing nitric oxide synthase (NOS) were examined in the nucleus of the solitary tract (NST) of the rat by NADPH diaphorase histochemistry combined with nodose ganglionectomy. Axon terminals with NADPH diaphorase activity were densely distributed in the middle and caudal part of the NST. After removal of the nodose ganglion (NG), most of the axon terminals with NADPH activity in the NST were eliminated on the ipsilateral side. These results indicated that most of the axon terminals with NADPH diaphorase in the NST derive from the primary afferent neurons in the NG, and that NOS may be richly contained in the central terminals of NG neurons to produce nitric oxide as a transmitter.

Amino Acid Oxidoreductases↗

PubMed1994

Treatment of adolescent myopia by pressure plaster of semen impatientis on otoacupoints.

295 cases (424 eyes) of adolescent myopia were treated by pressure plaster of Semen Impatientis on otoacupoints with a cure rate of 44.3% and a total effective rate of 98.5%. 36 random cases (69 eyes) were compared with the same number of similar control cases. Findings were that the therapeutic effects of the pressure plaster group excelled significantly those of the control group.

Acupuncture Points↗

PubMed1994

Comparative observations on the types of atrophic gastritis and biopsy pathology of gastric mucosa.

300 cases of chronic atrophic gastritis were classified into 3 types of qi-deficiency of spleen and stomach, yang-deficiency of spleen and stomach, and yin-deficiency of spleen and stomach according to syndrome differentiation of traditional Chinese medicine. The biopsy specimens of gastric mucosa were examined histopathologically and for the presence of pyloric spirobacteria. The results showed that the type of yin-deficiency was the most serious in the degree of pathologic changes, or the glandular atrophy and the interstitial inflammatory cellular infiltration, while the rate of pyloric spirobacteria presence was comparable in all types.

Biopsy↗

PubMed1993

The subdivisions of the intermediolateral nucleus in the sacral spinal cord of the cat.

The subdivisions of the sacral intermediolateral nucleus (IML) of the cat have been studied by using a double-labeling technique of retrograde Fluoro-gold (FG) and wheat germ agglutinin-conjugated horseradish peroxidase (WGA-HRP) tracing. The parasympathetic preganglionic neurons (PGNs) that were labeled by the FG injected into the pelvic nerve formed a 'V'-shaped column known as the sacral parasympathetic nucleus (SPN) in the sacral IML. The neurons that were labeled by the WGA-HRP applied to the lateral parabrachial nucleus (PBL) formed an elongated spindle-shaped column extending throughout the IML of the sacral segments. We designated it by the name of sacral visceral sensory nucleus (SVSN). These findings indicate that the sacral IML of the cat contain two distinct subdivisions, SPN and SVSN.

Animals↗