Biomedical subjects

L Zou

Publications and source records attributed to L Zou.

At least 55 records · Page 3Linked to original sources

PubMed2000

[Surgical correction of complete atrioventricular septal defect with tetralogy of Fallot].

OBJECTIVE: To report the surgical correction of complete atrioventricular septal defect with tetralogy of Fallot (AVSD-TOF). METHODS: Six consecutive patients aged 3 - 9 years underwent correction of complete AVSD-TOF. The two-patch technique for atrioventricular septal defect was used. The ventricular septal defect was closed through a right ventriculotomy and right atriotomy in each case. The commissure between the superior and inferior bridging leaflets of the left portion of the common atrioventricular valve was closed in each patient. RVOT obstruction was relieved by a transannular autologous pericardium with monocuspid valve. RESULTS: Postoperative complications included respiratory failure in 1 patient, low cardiac output syndrome in 1, and MOF in 1. There was one mortality because of MOF in the early postoperative period. Five survivors were followed up from 6 months to 5.5 years (mean 2.3 years). There was no late mortality and only one patient had mild left atrioventricular valve regurgitation. NYHA cardiac function was class I in 4 patients and class II in 1. CONCLUSIONS: AVSD-TOF can be corrected using the two-patch technique and closure of the ventricular septal defect through a combined approach using a right ventriculotomy and right atriotomy. Routine closure of the commissure of the left portion of the atrioventricular valve results in a low incidence of regurgitation. Good functional result can be achieved in most patients postoperatively.

Cardiac Surgical Procedures↗

PubMed2000

[Evaluation of the results of therapeutic lamellar keratoplasty and penetrating keratoplasty for fungal corneal ulcer].

OBJECTIVE: To evaluate the effects of therapeutic lamellar and penetrating keratoplasty for fungal corneal ulcer. METHODS: Donor corneas preserved in pure glycerine or water-free calcium chloride were used in corneal transplantation for fungal corneal ulcers that were poorly responsive to the anti-fungal medical treatment, 5% iodine was used in lamellar keratoplasty to kill the fungi in the recipient bed, and diluted or original solution of fluconazole was used in penetrating keratoplasty to wash the anterior chamber. RESULTS: In the lamellar keratoplasty group, there were 23 cases; 18 cases were cured with one surgery and 3 cases were cured after second surgery, the success rate being 91.3%. There were 2 cases with recurrence of corneal inflammation, and the lesion was controlled by penetrating keratoplasty. The penetrating keratoplasty group included 31 cases, of them, 27 cases were cured with one surgery and 4 eyes were enucleated due to recurrent corneal inflammation or refractive glaucoma. In the total 54 cases, the inflammation was controlled in 50 cases after therapeutic corneal transplantation, success rate being 92.6%. CONCLUSIONS: For those fungal corneal ulcers that are poorly responsive to anti-fungus eye drops, it is recommended to perform lamellar keratoplasty if the ulcer is located in the anterior 1/2 stroma, the key points of surgery are to remove the affected tissue completely and cauterize the recipient bed with 5% iodine. For deep ulcers or nearly perforative or perforated ulcers, diluted or original solution of diflucan is used to wash the anterior chamber during penetrating keratoplasty, that can help to improve the success rate.

Adolescent↗

PubMed2000

[The relationship of cellular DNA content with clinical stage and biological features of colorectal cancer].

The purpose of this study was to explore the relationship of cellular DNA content with clinical stage and biological features of cancer. Flow cytometry was performed on fresh specimens from 86 patients from 1997 to 1998. Forty-five (53.3%) specimens were found to contain cells with abnormal DNA (DNA nondiploidy). Although none of the sex, age, site, differentiation variables correlated with flow cytometric DNA ploidy, nondiploidy was associated with Dukes' stage and lymph node metastasis. Duke's A stage tumors were more frequently diploid than were more advanced tumors, but no difference between Duke's B, C and D stages were observed. These findings suggest that ploidy is associated with some pathological factors.

Aged↗

PubMed2000

High frequency color Doppler image of choroidal detachment.

PURPOSE: To study the Color Doppler Image (CDI) characteristics of choroidal detachment and the applied value of CDI. METHODS: Seventy-two cases (74 eyes) of choroidal detachment were studied retrospectively. RESULTS: The typical ultragraph of chroridal detachment displayed one or several smooth hemispherical or lobuler circular thick bands, with convex side toward vitreous cavity. Most of the choroidal detachments were located before the equator, a few of them were beyond the equator. CDI displayed blood flow singnal in the band. Pulse Doppler showed the frequency spectrum features of retinal detachment band were similar to those of central retinal vessels, whereas the frequency spectum features of choroidal detachment bend resembled those of ciliary artery in some cases of retinal detachment (RD) accompanied by choroidal detachment. CONCLUSION: CDI could make a correct and precise diagnosis of choroidal detachment.

Adolescent↗

PubMed1999

Selective agenesis of mesencephalic dopaminergic neurons in Nurr1-deficient mice.

Nurr1, a member of the nuclear receptor superfamily of transcription factors, has been found to be essential for the development of ventral midbrain dopamine (DA)ergic neurons. To study the regional selectivity and phenotypic specificity of regulation by Nurr1 of the genesis of DAergic neurons, we examined DAergic, serotonin (5-HT)ergic, norepinephrine (NE)ergic, cholinergic, glutamate (GLU)ergic, and gamma-aminobutyric acid (GABA)ergic neurons in the brains of Nurr1-deficient mice by immunohistochemistry and biochemistry. We demonstrated that in homozygous Nurr1-deficient mice (Nurr1-/-), DAergic neurons were totally absent in substantia nigra and ventral tegmental area, but preserved in other regions including diencephalon and hypothalamus, olfactory bulb (OB). Levels of DA in Nurr1-/- mice were decreased by 98% in striatum (Str) and 65% in OB. NEergic neurons in locus ceruleus, 5-HTergic neurons in raphe nuclei, and cholinergic neurons in basal forebrain and other regions were not changed. A 30% reduction of NE was found in the Str of Nurr1-/- mice. The levels of GLU and GABA and the activity of choline acetyl transferase in the brains of Nurr1-/- mice were not significantly altered. Our results demonstrate a selective and specific deficit of DA and absence of DAergic neurons in the mesencephalic structures of Nurr1-deficient mice, which resembles the pattern similar to that seen in patients with Parkinson's disease (PD). This model may contribute to our understanding of the mechanisms influencing DAergic cell survival in PD.

Animals↗

PubMed1999

Neuroprotection by pramipexole against dopamine- and levodopa-induced cytotoxicity.

Pramipexole, a novel non-ergoline dopamine (DA) agonist, has been applied successfully for treatment of Parkinson's disease (PD). We report here that pramipexole can protect dopaminergic cell line Mes23.5 against dopamine- and levodopa-induced cytotoxicity possibly through a mechanism related to antioxidant activity. In the MES 23.5 cultures, DA and L-DOPA induce a dose- and time-dependent cytotoxicity, as determined by tetrazolium salt and trypan blue assays. Furthermore, an in situ terminal deoxynucleotidyl transferase assay demonstrates that DA-induced cell death is apoptotic. Pretreatment with pramipexole in a concentration range (4-100 microM) significantly attenuates DA- or L-DOPA-induced cytotoxicity and apoptosis, an action which is not blocked by D3 antagonist U-99194 A or D2 antagonist raclopride. Pramipexole also protects MES 23.5 cells from hydrogen peroxide-induced cytotoxicity in a dose-dependent manner. In cell-free system, pramipexole can effectively inhibit the formation of melanin, an end product resulting from DA or L-DOPA oxidation. These results indicate that pramipexole exerts its neuroprotective effect possibly through a mechanism, which is independent of DA receptors but related to antioxidation or scavenging of free radicals (e.g. hydrogen peroxide). As a direct DA agonist and potentially neuroprotective agent, pramipexole remains attractive in the treatment of PD.

Animals↗

PubMed1999

Quantification of root surface plaque using a new 3-D laser scanning method.

There are no published reports in the literature objectively quantifying thickness of plaque on teeth. The aim of this study was to quantify plaque on a tooth surface and assess if this quantification correlates with a clinical index of plaque from each of 51 patients. Patients were instructed not to perform any oral hygiene on the day of the assessment. The Silness and Löe plaque index was scored and replicas were scanned using a co-ordinate measuring machine (CMM) and laser scanning probe. A replica was obtained from this surface before and after toothbrushing. Plaque adjacent to the gingival margin had a mean thickness of 0.106+/-0.118 mm (mean+/-SD) whilst mean plaque thickness 250 microm from the gingival margin was 0.053+/-0.052 mm (mean+/-SD). There was a significant correlation between the plaque index and the plaque thickness (p < or = 0.002). The finding that plaque is present in the greatest amount adjacent to the gingival margin supports a previously reported hypothesis that primary root carious lesions (PRCL's) may initiate adjacent to the gingival margin. This method quantifies plaque thickness on exposed root surfaces which correlates with the plaque index as well as illustrating how the morphological characteristics of teeth, gingivae and plaque can be studied in vivo from replicas recorded.

Adult↗

PubMed1999

Suppression of chronic experimental autoimmune neuritis by nasally administered recombinant rat interleukin-6.

Experimental autoimmune neuritis (EAN) is a CD4+ T-cell-mediated demyelinating disease of the peripheral nervous system (PNS) and serves as experimental model for human immune-demyelinating neurophathies, especially the Guillain-Barré syndrome. In this study, we examined the effect of recombinant rat interleukin-6 (rrIL-6) on chronic EAN in Lewis rats induced by immunization with P2 peptide 57-81 and Freund's complete adjuvant (FCA). Nasal administration of rat rIL-6 (1 microg/rat/day) beginning in the initial phase of EAN as a therapeutic agent, decreased the severity and the duration of clinical EAN. Low-grade inflammation and suppression of regional demyelination within the sciatic nerves were seen in rrIL-6-treated rats. Hyporesponsiveness of lymph node T cells, down-regulation of serum tumour necrosis factor-alpha (TNF-alpha) and increased levels of P2-specific immunoglobulin G1 (IgG1) antibodies document that nasal administration of rrIL-6 was effective systemically. However, because of the non-specific nature of the treatment and multiple effects of IL-6, more experience and great caution are needed, before nasal administration of IL-6 can be considered as a treatment of human autoimmune demyelinating neurophathies.

Administration, Intranasal↗

PubMed1999

[Distribution of six STR loci in Bai ethnic group in Yunnan province of China].

OBJECTIVE: This study was conducted to make known the distribution of six STR loci in Bai ethnic group in Yunnan province. METHODS: DAN extraction from blood samples (126 in number ) and multiplex amplification of CSF1PO,TPOX, TH01,F13A01, FESFPS and vWA were carried out. Using denaturing polyacrylamide gel electrophoresis and silver stain, the authors investigated the distribution of allele frequencies of CSF1PO, TPOX,TH01,F13A01,FESFPS and vWA loci in Bai ethnic group living in Yunnan province. RESULTS: 7 alleles and 19 genotypes of CSF1PO locus, 5 alleles and 11 genotypes of TPOX locus, 6 alleles and 16 genotypes of TH01 locus 6 alleles and 16 genotypes of F13A01 locus, 7 alleles and 15 genotypes of FESFPS locus,and 7 alleles and 21 genotypes of vWA locus were observed. CONCLUSION: The allele distribution of the loci was in good agreement with the Hardy-Weinberg equilibrium.

China↗

PubMed1999

[The genotype-based haplotype relative risk and transmission disequilibrium test analyses of familial febrile convulsions].

OBJECTIVE: To confirm the linkage of familial febrile convulsions to the short arm of chromosome 6(6p) or the long arm of chromosome 8(8q). METHODS: The authors finished genotyping of Pst I locus on the coding region of heat shock protein (HSP) 70, 5'untranslated region of HSP70-1, 3' untranslated region of HSP70-2, D8S84 and D8S85. The data were processed by the genotype-based haplotype relative risk(GHRR) and transmission disequilibrium test(TDT) methods in PPAP. RESULTS: Some signs of association and disequilibrium between D8S85 and FC were shown by GHRR and TDT. CONCLUSION: A suspect linkage of familial febrile convulsions to the long arm of chromosome 8 has been proposed.

Chromosomes, Human, Pair 6↗

PubMed1999

Assessing the quality of shoulder preparations for metal ceramic crowns.

Previous work by the authors indicates a tendency for academic clinicians to under prepare and over angle shoulder preparations for metal ceramic crowns. This has implications for the final restoration in terms of contour, appearance and strength. This study analysed ninety six preparations, forty eight in vitro and forty eight in vivo, performed by six clinicians. The results show a mean shoulder width of 0.804 +/- 0.274 mm and a mean shoulder angle of 116 +/- 18 degrees for preparations performed in vitro; and 0.892 +/- 0.337 mm and 121 +/- 24 degrees for preparations performed in vivo. Thus, despite recommendations that such crowns should have 1-1.5 mm, 90 degrees shoulders, many of the preparations studied here fell short of this, indicating a lack of consistency in preparation geometry and adherence to the perceived 'ideal' preparation for a metal ceramic crown.

Crowns↗

PubMed1999

[High voltage transmission electron microscope and X-ray double-crystal diffractometer observation of pure titanium implant-bone interface].

OBJECTIVE: To examine the integration of pure titanium implant and bone tissue. METHODS: Using low temperature dualion mill technique, the interface of titanium implant and bone was examined with high voltage transmission electron microscope and X-ray double crystal diffractometer. RESULTS: It was shown that calium globules of various electron density or sheets of calcified osseous tissue blended with titanium at the interface. The bone had grown in two directions. CONCLUSION: The integration of pure titanium implant and bone tissue is good, leaving no gap at their interface.

Animals↗

PubMed1999

[A SEM observation on taxonomic and pharmacognostical identification of genus murraya produced in China].

OBJECTIVE: To Observe the morphological characteristics of the leaf epidermis of 9 Chinese species of genus Murraya and prepare and index for their differentiation. METHOD: SEM(scanning electron microscope). RESULT: Sect. Murraya was found having with blurred dividing lines on epidermis without ropy emblazonry, while sect. Bergera appeared the other way round. CONCLUSION: M. kwangsiensis var. macrophylla should be ground under Sect. Murraya as a new species, while M. tetramera should be separated from M. euchrestifolia; SEM has been proved very useful in the identification, taxonomic and pharmacognostical study of Murraya.

Microscopy, Electron, Scanning↗

PubMed1999

[The experience of treatment of 7 cases of olfactory neuroblastoma].

OBJECTIVE: To improve the treatment result of olfactory neuroblastoma. METHOD: Introduce the experience of treatment of 7 patients with this disease. Among these 7 cases, 2 of them were stage B while the others were stage C according to the system proposed by Kadish. 3 cases received radiotherapy alone, and 4 others received radiotherapy pre-operation. The radiation dose was 5000-7000 cGy. All the patients were followed-up until December 1997. RESULT: 5 cases are still alive, survival time are 20, 22, 23, 29 and 76 months respectively. The other 2 patients died with the survival time of 6 and 48 months respectively. CONCLUSION: Radiotherapy seems effective in the treatment of olfactory neuroblastoma; the combination of chemo-radio-therapy is preferable for advanced or metastasis olfactory neuroblastoma. We extrapolate there are different subtypes on pathology in this tumor.

Adolescent↗

PubMed1999

[Study on carbazole alkaloids of Murraya microphylla].

Four carbazole alkaloids were isolated from the methanol extract of Murraya microphylla. Their structures were identified by spectral analysis and chemical evidence, which were identified as koenigine, bis-6-hydroxy-7-methoxygirinimbine, girinimbine and mukonicine. All the compounds were discovered from this plant for the first time, and bis-6-hydroxy-7-methoxygirinimbine was a new compound.

Alkaloids↗

PubMed1998

[Distribution of three STR loci in Dai ethnic group in China].

OBJECTIVE: This study was conducted to investigate the distribution of three STR loci in Dai ethnic group. METHODS: Multiplex amplifications of CSF1PO, TPOX and TH01 were carried out. Using denaturing polyacrylamide gel electrophoresis and silver staining the authors investigated the distribution of allele frequencies of CSF1PO, TPOX and TH01 loci in Dai ethnic group living in Yunnan province. RESULTS: 7 alleles and 15 genotype of CSF1PO locus, 7 alleles and 18 genotypes of TPOX locus, 6 alleles and 17 genotypes of TH01 locus were observed. CONCLUSION: The allele distribution of the loci is in good agreement with the Hardy-Weinberg equilibrium.

China↗

PubMed1998

Formation of a preinitiation complex by S-phase cyclin CDK-dependent loading of Cdc45p onto chromatin.

Cdc45p, a protein essential for initiation of DNA replication, associates with chromatin after "start" in late G1 and during the S phase of the cell cycle. Binding of Cdc45p to chromatin depends on Clb-Cdc28 kinase activity as well as functional Cdc6p and Mcm2p, which suggests that Cdc45p associates with the prereplication complex after activation of S-phase cyclin-dependent kinases (CDKs). As indicated by the timing and the CDK dependence, binding of Cdc45p to chromatin is crucial for commitment to initiation of DNA replication. During S phase, Cdc45p physically interacts with minichromosome maintenance (MCM) proteins on chromatin; however, dissociation of Cdc45p from chromatin is slower than that of MCMs, which indicates that the proteins are released by different mechanisms.

CDC28 Protein Kinase, S cerevisiae↗

PubMed1998

[Distribution of three STR loci in Jingpo ethnic group in Yunnan province].

OBJECTIVE: This study was aimed at the use of old blood stains for investigating the distribution of three STR loci in Jingpo ethnic group. METHODS: DNA extraction from old blood stains (106 in number) and multiplex amplification of CSF1PO, TPOX and TH 01 were carried out. Using denaturing polyacrylamide gel electrophoresis and silver stain, the authors investigated the distribution of allele frequencies of CSF1PO, TPOX and TH01 loci in a Jingpo ethnic group in the southwestern part of Yunnan province. RESULTS: 7 alleles and 26 genotypes of CSF1PO locus,7 alleles and 19 genotypes of TPOX locus, and 6 alleles and 18 genotypes of TH01 locus were observed. CONCLUSION: The satisfactory results demonstrate that multiplex amplification of CSF1PO, TPOX and TH01 is sensitive and the old stain of a drop of blood is sufficient for such amplification.

Asian People↗