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H Ye

Publications and source records attributed to H Ye.

At least 91 records · Page 5Linked to original sources
PubMed1996

Efficient adenovirus-mediated gene transfer to basal but not columnar cells of cartilaginous airway epithelia.

Adenoviral vectors (AdV) developed for treatment of the pulmonary manifestations of cystic fibrosis (CF) can deliver, with high efficiency, transgenes to respiratory epithelial cells grown in culture. This study investigated the efficiency of AdV-mediated gene transfer to murine and human respiratory epithelium in vivo and concluded that the epithelial cells facing the lumen of the respiratory cartilaginous airways (columnar cells) are poorly transduced with AdV. Mechanical injury to the epithelium, however, leads to efficient in vivo gene transfer by exposing a susceptible epithelial subtype (basal cells). Increased gene transfer efficiency in vivo after injury is not a nonspecific response because the proliferative status of the epithelium after injury was shown not to correlate temporally to the increased transduction susceptibility of the epithelium. Although basal cells were the cell type transduced at the time of vector delivery, with time, basal cell differentiation to columnar cells occurred with maintenance of transgene expression. Collectively, these results show that murine and human cartilaginous airways are poorly transduced by AdV. To correct the cartilaginous airway CF bioelectrical defect in vivo, efforts should be directed to increase the tropism of AdV to the columnar airway epithelial cells.

Adenoviridae↗
PubMed1996

In vitro assessment of variables affecting the efficiency and efficacy of adenovirus-mediated gene transfer to cystic fibrosis airway epithelia.

Primary cultures of airway epithelia were used to evaluate variables pertinent to adenovirus (Ad)-mediated gene transfer efficiency and efficacy including: (i) Ad-vectors with different promoters, (ii) the duration of vector incubation with cells, (iii) the concentration and depth of vector-containing medium at constant multiplicity of infection (moi) (10(3)), and (iv) the relative sensitivity of reverse transcription polymerase chain reaction (RT-PCR) versus functional analysis for the detection of transduced cystic fibrosis transmembrane conductance regulator (CFTR). An Ad5-lacZ vector with a cytomegalovirus (CMV) enhancer/promoter transduced the greatest amount of beta-galactosidase (beta-Gal) activity, while an Ad2-lacZ vector with an E1a enhancer/promoter transduced the least. Ad5-lacZ vectors with the Rous sarcoma virus (RSV), E1a/RSV, or CMV enhancer/beta-actin (CB) promoters transduced intermediate levels of beta-Gal. Optimal gene transfer efficiency was detected with a 4-8 hr incubation of Ad5-CMVlacZ with cells, although optimal CFTR Cl-transport function was detectable after only a 30 min incubation of Ad5-CBCFTR with cells, consistent with correction of > or = 6-10% of cells in the epithelial sheet. Ad5-CBCFTR transduction of CF airway epithelial cells (moi = 10(3)) was optimal when higher concentrations, lower volumes, or smaller depths of vector-containing medium were utilized. RT-PCR was at least 100-fold more sensitive for the detection of transduced CFTR than functional analysis, and could detect as few as 0.001% Ad5-CBCFTR-infected CF cells admixed with uninfected CF cells. In summary, the variables studied clearly affect the efficiency of Ad-mediated gene transfer in vitro and potentially in vivo. They also suggest that RT-PCR is a poor marker of gene transfer efficiency and efficacy.

Adenoviruses, Human↗
PubMed1996

Treatment of chancroid with azithromycin.

A randomized, comparative study undertaken in Nairobi, Kenya and a non-comparative evaluation undertaken in Carletonville, South Africa have both shown that a single oral dose of azithromycin 1 g is effective in the treatment of the genital ulcer disease (GUD), chancroid, with cure rates of 89% and 92% recorded respectively. While treatment failure was associated with human immunodeficiency virus seropositivity and lack of circumcision in Kenya, no such association could be found in the South African study. In both series, azithromycin treatment resulted in cure of both Haemophilus ducreyi culture-positive and culture-negative cases of GUD, including two cases subsequently diagnosed as lymphogranuloma venereum. A combination of single-dose azithromycin with single-dose benzathine penicillin may provide effective 'single-visit' syndromic treatment for GUD in many developing countries.

Anti-Bacterial Agents↗
PubMed1996

[Effects of intermittent short-course chemotherapy under full-course supervision on the treatment of smear positive pulmonary tuberculosis].

OBJECTIVE: To evaluate the effects of intermittent short-course chemotherapy under full-course supervision on the treatment of smear positive pulmonary tuberculosis. METHOD: The regimens of 2H3R3Z3S3(E3)/4H3R3 and 2H3R3Z3S3E3/6H3R3E3 were respectively used in 125 initial and 249 relapse smear positive pulmonary tuberculosis cases under full-course supervision and management. RESULTS: The total rate of treatment completion was 99.7%, and the rates of sputum negative conversion in initial and relapse cases were 96.7% and 84.8% respectively. During three-year follow-up, the bacteriological relapse rates were found to be 1.8% in initial cases and 10.2% in relapse cases. CONCLUSIONS: The regimen was proved to be convenient, economical and effective in tuberculosis control programme.

Antitubercular Agents↗
PubMed1995

Heterogeneity of astrocytes in human optic nerve head.

Previous studies demonstrated regional differences in the synthesis of extracellular matrix by astrocytes during optic nerve head (ONH) maturation and in glaucomatous optic neuropathy, suggesting heterogeneity of astrocytes. To characterize different types of glial cells in human fetal and adult ONH, we used a variety of neural cell markers such as HNK-1/N-CAM, A2B5, galactocerebroside (GalC), myelin basic protein (MBP), and glial fibrillary acidic protein (GFAP). Cryostat or paraffin sections were prepared from fetal (16-25 weeks) and mature (8 months to 75 years old) ONH and processed for standard single/double immunocytochemistry. Two subpopulations of type 7 astrocytes were present in the mature prelaminar and laminar regions. Glial cells expressing only GFAP were identified as type 1A astrocytes at the edges of the cribriform plates. Cells forming the glial columns and lining the cribriform plates expressed both GFAP and HNK-1/N-CAM and were identified as type 1B astrocytes. In the myelinated nerve, type 1A astrocytes form the glial limiting membrane. Cells labeled with GFAP and A2B5 were identified as type 2 astrocytes, and GFAP-negative cells labeled with GalC, MBP, and HNK-1/N-CAM were identified as oligodendrocytes. In fetal ONH, all glial cells expressed HNK-1/N-CAM. In older fetal ONH, some glial cells also expressed GFAP. No type 2 astrocytes or oligodendrocytes were present in the fetal ONH. In conclusion, at least two subpopulations of type 1 astrocytes exist in human ONH: Type 1A astrocytes may serve as structural support for axons; type 1B astrocytes, which retain the developmental neural marker HNK-1/N-CAM, may have a more complex function by interfacing between blood vessels and other connective tissue surfaces. These findings demonstrate the heterogeneity of astrocytes in the human ONH and suggest differential regional responses to changes in their microenvironment.

Adult↗
PubMed1995

Elastosis of the lamina cribrosa in pseudoexfoliation syndrome with glaucoma.

BACKGROUND: Pseudoexfoliation syndrome is characterized by the presence of glycoprotein fibers in ocular and extraocular tissues, and often is associated with glaucoma. Pseudoexfoliation material may be associated closely with elastic microfibrillar-associated glycoprotein as well as elastin. METHODS: Four optic nerve heads of two patients with pseudoexfoliation syndrome and glaucoma were examined using electron microscopy and immunogold detection of elastin. Optic nerve heads from healthy age-matched individuals and patients with primary open-angle glaucoma were used for comparisons. RESULTS: In all eyes with pseudoexfoliation and glaucoma, there was marked and widespread elastosis in the connective tissue of the lamina cribrosa. Elastotic fibers appeared as large and irregular aggregates of electron-dense material labeled with anti-elastin antibody. Abundant microfibrils were interspersed in the elastotic aggregates, whereas no typical pseudoexfoliation fibers were observed. In contrast, there were less elastotic fibers in the lamina cribrosa from patients with primary open-angle glaucoma compared with pseudoexfoliation glaucoma. Other changes of extracellular matrix were similar to those observed in primary open-angle glaucoma: decreases in collagen fiber density, presence of basement membranes not associated with cell surfaces, and abundant bundles of microfibrils not labeled with elastin antibody. The elastic fibers appeared normal in other locations within the optic nerves of patients with pseudoexfoliation glaucoma, including in the pial septa and blood vessels of the retrolaminar myelinated optic nerve. CONCLUSION: The authors' findings demonstrate marked and site-specific elastosis in the lamina cribrosa of patients with pseudoexfoliation syndrome with glaucoma, suggesting an abnormal regulation of elastin synthesis and/or degradation in the optic nerve of patients with this disease.

Aged↗
PubMed1995

[The effective time of HX solution for rat liver preservation].

The effects of HX solution and UW solution for rat liver preservation were studied with non-circulated isolated perfused rat liver model. Sixty-six inbred Wistar rat livers were randomly preserved for 12, 18, 24, and 30h with HX solution or UW solution. The effects were assessed by measuring hepatic tissue water content, sinusoidal lining cell mortality, Krebs-Henseleit's perfusate aspartate aminotransferase, the number of livers secreting bile during isolated perfusion, and by observing the morphological changes in liver. The experimental results suggest that the effects of HX solution for rat liver preservation be similar to those of UW solution within 24h storage.

Adenosine↗
PubMed1995

Rabies viral antigen in human tongues and salivary glands.

Lingual and major salivary tissue samples from three cases of rabies were stained with the immunoperoxidase (ABC) technique. All tissue blocks had been embedded in paraffin 4-10 years before. The first antibody used was monoclonal antirabies nucleocapsin (N) mouse antibody (HAM). Four out of five pieces of tongue from two cases showed a large amount of granular staining indicating rabies antigen (RVAg) inside serous glandular cells, terminal nerves, muscle cells and covering epithelial cells including taste cells. In the tissue probes from the third case only minimal granular staining was found, probably due to complete absence of the serous gland. In contrast to the tongue, only a little weakly reacting material was found in 4 out of 9 probes of salivary gland, either in acini or in nerve fibres. The amount of RVAg is evidently much greater in the human tongue than in major salivary glands, whereas major salivary glands from infected dogs, foxes and skunks reportedly contain much RVAg. As the human tongue's serous gland appears to be a preferred location for RVAg, it may be a source of oral infection.

Adolescent↗
PubMed1995

Hairy root culture of Artemisia annua L. by Ri plasmid transformation and biosynthesis of artemisinin.

The hairy root culture system of the medical plant Artemisia annua L. was established by infection with Agrobacterium rhizogenes R1601. The transgenic state of transformed roots was confirmed by Southern blot hybridization with TL-DNA of pFw302. The expression of NPTII gene was confirmed by enzymic assay. The important secondary metabolites-artemisinin was obtained in the hairy root culture. The effects of various physical and chemical factors on the growth of the hairy roots and production of artemisinin were studied. Artemisinin could be detected in hairy roots cultures in the light. The optimum pH value of the medium was 5.4. Fast growth of the hairy roots and maximal production of artemisinin was observed in the presence of 3% sucrose. Low concentration of naphthylacetic acid (0.025 mg/L) enhanced the growth of the roots but inhibited the production of artemisinin. The growth and artemisinin production in hairy root cultures were greatly promoted by the addition of gibberellin (GA3) to the medium. Its optimum concentration was 4.8 mg/L.

Antimalarials↗
PubMed1994

Inefficient gene transfer by adenovirus vector to cystic fibrosis airway epithelia of mice and humans.

The success of adenoviral vectors for gene therapy of lung disease in cystic fibrosis (CF) depends on efficient transfer of the complementary DNA encoding the correct version of the cystic fibrosis transmembrane regulator (CFTR) to the affected columnar epithelial cells lining the airways of the lung. Pre-clinical studies in vitro suggest that low doses of adenovirus vectors carrying this CFTR cDNA can correct defective Cl- transport in cultured human CF airway epithelia. Here we use mice carrying the disrupted CF gene to test the efficacy of this transfer system in vivo. We find that even repeated high doses can only partially (50%) correct the CF defect in Cl- transport in vivo and do not correct the Na+ transport defect at all. We investigated this discrepancy between the in vivo and in vitro transfer efficiency using CF mouse and human samples, and found that it reflects a difference in the susceptibility to adenovirus-5 transduction of the epithelial cell types dosed in vivo (columnar) and in vitro (basal-cell-like). These studies indicate that more efficient adenoviral gene-transfer vectors and/or refinement of dosing strategies are needed for therapy of CF lung disease.

Adenoviruses, Human↗
PubMed1994

Members of the HNF-3/forkhead family of transcription factors exhibit distinct cellular expression patterns in lung and regulate the surfactant protein B promoter.

The hepatocyte nuclear factor-3 (HNF-3)/forkhead (fkh) proteins consist of an extensive family of tissue-specific and developmental gene regulators which share homology within the winged helix DNA binding motif. We report on the isolation of a new family member, HNF-3/forkhead homolog 8 (HFH-8), from lung cDNA libraries and the derivation of the complete amino acid sequences for the HFH-8 protein as well as previously identified HFH-1 and HFH-4 proteins. The HFH proteins contain several sequence motifs found in activation domains of other transcription factors and HNF-3/fkh family members. In situ hybridization with the HNF-3, HFH-4, and HFH-8 probes in adult lung demonstrate that the HNF-3/fkh cellular expression patterns are regionally specified. Whereas HNF-3 alpha and HNF-3 beta are normally coexpressed in the hepatocyte, their expression patterns in the lung are different. The HNF-3 alpha and HFH-4 genes are coexpressed in the bronchiolar epithelium (clara cells), whereas the HNF-3 beta probe exhibits prominent hybridization with the smooth muscle surrounding arterioles and bronchioles. In contrast, HFH-8 probes labeled the type II pneumocyte cells lining the respiratory surfaces of terminal bronchioles and alveolar sac. We have identified an HNF-3 consensus DNA binding sequence in the proximal surfactant protein B (SPB) promoter region (SPB-f2, -78 to -88). SPB gene transcription is restricted to bronchiolar and alveolar epithelium which colocalizes with the expression pattern of the HNF-3 alpha and HFH-8 genes, respectively. We show that the SPB-f2 sequence is recognized by both HNF-3 alpha and HFH-8 proteins and that these cDNA expression vectors activate the SPB promoter in cotransfection assays through the HNF-3 consensus sequence. Our results suggest that SPB promoter activity is regulated by HNF-3 alpha and HFH-8 proteins in a cell type-specific manner.

Aging↗
PubMed1994

Collagen type IV gene expression in human optic nerve heads with primary open angle glaucoma.

Previous studies have demonstrated proliferation of basement membranes in the optic nerve head in primary open angle glaucoma (POAG). We used in situ hybridization (ISH) of a radiolabeled riboprobe specific for human collagen IV, a ubiquitous component of basement membranes, to identify cells actively synthesizing basement membranes in the optic nerve head in POAG. In addition, to detect and further characterize the collagen IV mRNA transcripts, we used reverse transcriptase-polymerase chain reaction (RT-PCR) in total RNA extracted from individual optic nerve heads with POAG and from age-matched normal controls. ISH results demonstrate that, in POAG, numerous astrocytes in the prelaminar region expressed collagen IV mRNA. Lamina cribrosa cells and astrocytes in the compressed lamina cribrosa hybridized the probe. Few astrocytes and lamina cribrosa cells hybridized the probe in the optic nerve head of normal age-matched controls. RT-PCR products for collagen IV and for glyceraldehyde-3-dehydrogenase (G3PDH), a reference gene, were detected by agarose electrophoresis as single bands of the expected sizes and positively identified by Southern hybridization using specific cDNA probes in normal and POAG samples. No additional products (bands) were observed in RT-PCR experiments, indicating that there was no genomic DNA contamination in the total RNA extract. The lack of additional bands suggests that, at least in the ten samples used in this study, there were no alternatively spliced RNA products in any of the amplified sequences. Semi-quantitative analyses using densitometry showed a two-fold increase in collagen type IV PCR present in POAG samples. No differences were detected in levels of G3PDH PCR products between POAG and normal samples. This investigation provides evidence of increased biosynthesis of collagen type IV at the mRNA level in optic nerve heads with POAG. Whether this phenomenon represents a response to elevated intraocular pressure or a reparative mechanism to the loss of axons remains to be determined.

Aged↗
PubMed1994

Localization of collagen type III mRNA in normal human optic nerve heads.

Previous studies using immunocytochemistry and electron microscopy have localized collagen type III (CIII) in the human optic nerve head (ONH). CIII is present in the core of the cribriform plates of the lamina cribrosa and increases with age. In this study, in situ hybridization was used to localize mRNA for CIII in specific cells in human fetal and adult ONH to determine its cellular origin and to provide temporal and regional information on the synthesis of CIII in the ONH. Human ONH from donors with no history of eye disease (16-24 weeks gestation and 6-75 years) were fixed, embedded and sectioned serially. Sections were hybridized with antisense riboprobe for CIII and controls with sense riboprobe and processed for ISH. Immunoperoxidase staining with antibodies against GFAP and von Willebrand factor was used to detect astrocytes and vascular endothelial cells respectively. Fetal ONH: CIII mRNA was localized in most blood vessels throughout the ONH in sections hybridized with antisense probe. The label was localized to endothelial cells of small vessels. Endothelial cells of central retinal vessels were not labeled. In the lamina cribrosa, CIII mRNA was localized to small vessels, but not to astrocytes. Fibroblasts of the peripapillary sclera were labelled with antisense probe. Young-Adult ONH: In the cribriform plates, lamina cribrosa cells hybridized the probe at all ages. Few astrocytes hybridized the probe. Some endothelial cells of small vessels were also labeled. In the insertion region, most vessels were labeled in young ONH, but very few, if any, in old adults. The apparent intensity of hybridization signal associated with blood vessels in adult ONH is markedly reduced with age. No hybridization was observed inside of nerve bundles consistent with the absence of mRNA inside axon and CIII in this location. Localization of mRNA for CIII to blood vessels in fetal lamina cribrosa suggests a vascular origin for CIII in the plates, and perhaps, for lamina cribrosa cells. In young and old lamina cribrosa, localization of CIII mRNA suggests lifelong synthesis of this protein in agreement with age-related increase of CIII in this tissue.

Adolescent↗
PubMed1994

Role of a 35 kDa fos-related antigen (FRA) in the long-term induction of striatal dynorphin expression in the 6-hydroxydopamine lesioned rat.

D1 dopamine (DA) receptor agonists induce the expression of the opioid peptide dynorphin (DYN) in the striatum, an effect accentuated several fold by removing the dopaminergic innervation to the striatum (e.g., by lesioning the DA cell bodies in the substantia nigra [SN]). D1 receptor-mediated effects are thought to involve cAMP and/or phosphoinositides as second messengers. However, it is unclear what third messengers are involved in the regulation of DYN expression. The present experiments evaluated the possible role of two families of immediate-early gene (IEG) proteins, Fos and Jun, in the induction of DYN biosynthesis following repeated treatment with DA agonists. In addition, the role of N-methyl-D-aspartate (NMDA) receptors in modulating DA-induced changes in DYN and IEG protein expression was assessed. Adult male rats received unilateral 6-hydroxydopamine (6-OHDA) or sham lesions of the SN. Following a recovery period, animals were injected twice daily with the DA agonist, apomorphine (APO; 5 mg/kg), for 4 or 7 days. As expected, APO induced DYN biosynthesis, at both the peptide and mRNA level, several fold more in the striatum ipsilateral to the 6-OHDA lesion than in the contralateral control side (or a sham lesioned striatum). These effects appeared to be mediated by D1 receptors since the D1 agonist, SKF 38393 (5 mg/kg), caused the same changes in DYN expression as APO whereas a D2 agonist, quinpirole (1 mg/kg), had no effect. Paralleling the increase in DYN expression, APO also induced the expression of c-Fos and Fos-related antigens (FRA's), in particular a 35 kDa FRA, but had no effect on the expression of various Jun-related IEG proteins (i.e., c-Jun, Jun B, Jun D). Consistent with the notion that Fos and FRA proteins alter transcriptional activity by binding to AP-1 (or AP-1-like) DNA sequences in the promoter regions of target genes, we found that repeated APO treatment caused large increases in AP-1 binding activity in striata ipsilateral to 6-OHDA lesions. These data indicate that repeated activation of D1 receptors increases both the expression of a 35 kDa FRA and AP-1 binding, events which may mediate the large increases in DYN expression in the DA denervated striatum. While co-administration of the NMDA receptor antagonist, MK-801, inhibited APO-induced increases in DYN and Fos/FRA expression in the intact striatum, its only effect in the DA-denervated striatum was a partial (35%) inhibition of the APO-induced increase in DYN-ir concentrations.(ABSTRACT TRUNCATED AT 400 WORDS)

2,3,4,5-Tetrahydro-7,8-dihydroxy-1-phenyl-1H-3-ben↗