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J Xu

Publications and source records attributed to J Xu.

At least 1,045 records · Page 58Linked to original sources
PubMed1995

Cloning and functional characterization through antisense mapping of a kappa 3-related opioid receptor.

We have identified a putative opioid receptor from mouse brain (KOR-3), belonging to the G protein-coupled receptor family, that is distinct from the previously cloned mu, delta, and kappa 1 receptors. Assignment of the clone to the opioid receptor family derives from both structural and functional studies. Its predicted amino acid sequence is highly homologous to that of the other opioid receptors, particularly in many of the transmembrane regions, where long stretches are identical to mu, delta, and kappa 1 receptors. Both cyclazocine and nalorphine inhibit cAMP accumulation in COS-7 cells stably expressing the clone. Northern analysis shows that the mRNA is present in brain but not in a number of other organs. Southern analysis suggests a single gene encoding the receptor. A highly selective monoclonal antibody directed against the native kappa 3 receptor recognizes, in Western analysis, the clone expressed in COS-7 cells. The in vitro translation product is also labeled by the antibody. Additional clones reveal the presence of several introns, including one in the second extracellular loop and another in the first transmembrane region. Antisense studies with an oligodeoxynucleotide directed against a region of the second extracellular loop reveal a selective blockade of kappa 3 analgesia in vivo that is not observed with a mismatch oligodeoxynucleotide based upon the antisense sequence. The mu, delta, and kappa 1 analgesia is unaffected by this antisense treatment. Antisense mapping of the clone downstream from the splice site in the first transmembrane region reveals that six different antisense oligodeoxynucleotides all block kappa 3 analgesia. In contrast, only one of an additional six different antisense oligodeoxynucleotides directed at regions upstream from this splice site is effective. This strong demarcation between the two regions raises the possibility of splice variants of the receptor. An additional clone reveals an insert in the 3' untranslated region. In conclusion, the antibody and antisense studies strongly associate KOR-3 with the kappa 3-opioid receptor, although it is not clear whether it is the kappa 3 receptor itself or a splice variant.

Amino Acid Sequence↗
PubMed1995

[Pathological and immunohistochemical studies on primary nasal mucosal malignant melanoma].

The pathological and immunohistochemical features of primary nasal mucosal malignant melanoma (PNMMM) were reported in 40 cases. The results showed that approximate 70% of PNMMM was polypoid. The principal features were the mixed existance of different cellular patterns and morphologies. Immunohistochemically, PNMMM reactivity to S-100 protein and vimentin was 90% and 77.5%, respectively, along with no reactivity to Keratin. We believe that PNMMM may arise from preexistant melocytes in nasal mucosa. Histological pleomorphism and immunohistochemical reactivity to S-100 protein and vimentin were of importance for diagnosis of PNMMM, especially for the amelanotic type.

Adult↗
PubMed1995

[An epidemiological survey of primary angle-closure glaucoma in Doumen county Guangdong].

A comparison between the results of an epidemiological study of primary angle-closure glaucoma (PACG) in Doumen County, Guangdong in 1990 and those of a similar study in Shunyi County, Beijing in 1985 was reported. The prevalence of PACG in subjects over 45 years old was 0.64% and that, over 50 years, 0.85% in Doumen, while that, over 50 years, 1.99% in Shunyi (P < 0.05). There was significant difference in the prevalence of PACG between the two counties and the difference was discussed.

Aged↗
PubMed1995

[Evaluation of chemosensitivities of human breast cancers by primary culture assay in vitro].

Chemosensitivities of 32 human breast cancer to 6 antitumor drugs were assayed in vitro using MTT colorimetric method. The results showed that the chemosensitivity of primary breast cancer cultures varied remarkably from one patient, and from one drug, to another with hundred-to thousand-fold differences. The distribution of 50% inhibition concentration (IC50) was significantly deviated from normal distribution (P < 0.0001), and the drug sensitivity could be divided into four different catagories by means of percentile method. Preliminary results showed that the in vitro chemosensitivities of different antitumor drugs were consistent with the clinical therapeutic responses It seems that the herein reported assay might be useful on an individual basis to optimize chemotherapy of human breast cancer.

Antineoplastic Agents↗
PubMed1995

Evidence for two unlinked loci regulating total serum IgE levels.

Studies investigating the genetic control of total serum IgE levels are of major importance in understanding basic pathophysiologic mechanisms in atopy and asthma, since IgE levels predict onset and correlate with the clinical expression of these disorders. Previous analysis of data from 92 families, ascertained through a parent with asthma, showed evidence for recessive inheritance of high IgE levels with linkage to chromosome 5q. Since there was significant residual familial correlation in the one-locus segregation analysis, two-locus segregation and linkage analyses were performed. Segregation analyses provided evidence for a second major locus unlinked to the locus on 5q. Utilization of this two-locus model corroborates the previous evidence for linkage between this trait and markers on 5q31-q33. The LODs for the most informative marker D5S436 increased from 3.00 at 10% recombination to 4.67 at 9% recombination, when the two-locus model was used. Additional linkage studies are needed to map this second locus. These results demonstrate the importance of performing multilocus segregation and linkage analyses for quantitative traits that are related to the phenotype of a complex disorder. This approach has given further insight into the genetics of allergy and asthma by providing evidence for a two-locus model.

Asthma↗
PubMed1995

Investigations on a curved intracochlear array.

A curved electrode array and inserting tool have been developed at the University of Melbourne. This electrode array can be successfully implanted with few modifications to the surgical procedure presently in use. When implanted, the curved electrode array adopts a position closer to the modiolus than does the standard straight electrode array.

Cochlear Implants↗
PubMed1995

Encircling suture method in the treatment of femoral venous valvular incompetency.

Many patients with chronic venous insufficiency syndrome caused by the "relative valvular incompetency" with venous dilatation. Eighty-six per cent of the cases can be cured by reducing the femoral venous diameter by simply using the encircling suture method just distal to the first femoral valvular sinus. Our preliminary results suggest that such a method of surgical treatment is simple and efficient.

Adult↗
PubMed1995

The population association of glucokinase gene with type 2 (noninsulin-dependent) diabetes mellitus in Chinese.

The association of gluckinase (GCK) gene with type 2 (non-insulin-dependent) diabetes mellitus was investigated in 168 Chinese subjects (85 unrelated type 2 diabetics and 83 non-diabetic controls). The microsatellite polymorphism marker, GCK-5', was amplified with polymerase chain reaction. Four alleles were observed in Chinese population with length varying from 137bp to 143bp and the most common one being the 139bp allele 3. In comparison with non-diabetics, allele 4 was significantly increased in type 2 diabetes (10% versus 38, respectively; X2 = 6.773, P = 0.009); genotype 44 and 4X (X denotes any allele other than allele 4) were significantly increased in type 2 diabetes (16% versus 6% respectively; X2 = 6.439, P = 0.011). The frequency difference was also shown in overweight/obese subgroup comparison (X2 = 7.718, P = 0.021), but not in lean/normal-weight subgroup comparison. No differences of age of onset and frequency of positive family history were observed between type 2 diabetic patients with genotype 44 or 4X and those with XX. The risk for type 2 diabetes in Chinese with genotype 44 or 4X was about 3.5 times higher than in Chinese with genotype XX. Therefore, GCK gene was associated with Chinese type 2 diabetes.

Adult↗
PubMed1995

[Experimental study on acute hypoxia in newborn rabbits].

To investigate the hypoxic-ischemic damage of perinatal asphyxia, the acute hypoxic models of newborn rabbits were established and the effects of ligustrazine and anisodamine on pulmonary arterial pressure (PAP), dural blood flow (DBF) and blood gas of the hypoxia rabbits were observed. Acute hypoxia was caused by inhalation of 10% O2 + 90% N2 mixture. PaO2 was obviously reduced, PAP and DBF were obviously increased. But PAP in ligustrazine group did not increase and the elevated level of PAP in the anisodamine group was lower than the control. DBF and PaO2 was not affected by using both of the drugs. Ligustrazine and anisodamine might be effective for preventing and treating newborn persistent pulmonary hypertension.

Acute Disease↗
PubMed1995

Refinement of the spinal muscular atrophy locus by genetic and physical mapping.

We report the mapping and characterization of 12 microsatellite markers including 11 novel markers. All markers were generated from overlapping YAC clones that span the spinal muscular atrophy (SMA) locus. PCR amplification of 32 overlapping YAC clones shows that 9 of the new markers (those set in italics) map to the interval between the two previous closest flanking markers (D5S629 and D5S557): cen-D5S6-D5S125-D5S435-D5S1407- D5S629-D5S1410-D5S1411/D5S1412-D5S1413- D5S1414-D5Z8-D5Z9-CATT1-D5Z10/D5Z6- D5S557-D5S1408-D5S1409-D5S637-D5S351-MA P1B-tel. Four of these new markers detect multiple loci in and out of the SMA gene region. Genetic analysis of recombinant SMA families indicates that D5S1413 is a new proximal flanking locus for the SMA gene. Interestingly, among the 40 physically mapped loci, the 14 multilocus markers map contiguously to a genomic region that overlaps, and perhaps helps define, the minimum genetic region encompassing the SMA gene(s).

Base Sequence↗
PubMed1995

Evidence for linkage of bipolar disorder to chromosome 18 with a parent-of-origin effect.

A susceptibility gene on chromosome 18 and a parent-of-origin effect have been suggested for bipolar affective disorder (BPAD). We have studied 28 nuclear families selected for apparent unilineal transmission of the BPAD phenotype, by using 31 polymorphic markers spanning chromosome 18. Evidence for linkage was tested with affected-sib-pair and LOD score methods under two definitions of the affected phenotype. The affected-sibpair analyses indicated excess allele sharing for markers on 18p within the region reported previously. The greatest sharing was at D18S37: 64% in bipolar and recurrent unipolar (RUP) sib pairs (P = .0006). In addition, excess sharing of the paternally, but not maternally, transmitted alleles was observed at three markers on 18q: at D18S41, 51 bipolar and RUP sib pairs were concordant for paternally transmitted alleles, and 21 pairs were discordant (P = 0004). The evidence for linkage to loci on both 18p and 18q was strongest in the 11 paternal pedigrees, i.e., those in which the father or one of the father's sibs is affected. In these pedigrees, the greatest allele sharing (81%; P = .00002) and the highest LOD score (3.51; phi = 0.0) were observed at D18S41. Our results provide further support for linkage of BPAD to chromosome 18 and the first molecular evidence for a parent-of-origin effect operating in this disorder. The number of loci involved, and their precise location, require further study..

Adolescent↗
PubMed1995

[Characteristics and recent trends in endemicity of human parasitic diseases in China].

An analysis of the nationwide survey of the distribution of human parasites in the light of the literature previously published, two major trends in the endemicity of parasitic diseases in China was observed. For one trend, the infection rate of E. histolytica, Fasciolopsis buski and soil-transmitted helminthasis etc. declined markedly. The second trend was that the prevalence of food-transmitted parasitic diseases (Trichinella spiralis, Clonorchis sinensis, Paragonimiasis, cysticercosis) and hydatidosis was increasing. The relationship between the social economic factors and the two trends were discussed.

Animals↗
PubMed1995

Epidemiological survey of primary angle-closure glaucoma in Doumen.

PURPOSE: To determine the prevalence of primary angle-closure glaucoma (PACG) in Doumen Countty, Guangdong province. METHODS: Four villages from eight districts in doumen were selected by stratified, cluster and random sampling. Of a total of 1055 people aged 45 years or over, 932 (88.62%) were examined. The examination and diagnostic criterion were similar to those of shunyi survey. RESULTS: The prevalence of PACG in subjects over 45 year of eye is 0.64%, in those over 50 years of age is 0.85% in Doumen, which is significantly lower than the corresponding figure of 1.99% in shunyi (P < 0.05). CONCLUSION: This study identifies the prevalence of PACG in Doumen is lower than in Shunyi.

Aged↗
PubMed1995

[Clinical and experimental study on inhibitory effect of sanhuang mixture on platelet aggregation].

Sanhuang mixture (Xinmai capsule) is composed of Astragalus membranaceus, Coptis chinensis and Scutellaria baicalensis. It could inhibit platelet aggregation (PAG) induced by ADP in rats or by ADP and ADR in vivo. Patients with high PAG took Xinmai capsule for 4 weeks, the effective rate was 88.7%, which was same as the efficacy of aspirin 50 mg/day. In Syndrome Differentiation of TCM, the effective rate was the highest (92.3%) in the Syndrome of Qi Deficiency-Blood Stasis, and the lowest (72.7%) in the Syndrome of Stasis Phlegm and combined together.

Adult↗
PubMed1995

Some fluorescent properties of non-enzymic transamination and measurement of the relative molecular mass of protein.

A procedure for transaminating proteins and removing the transaminated N-terminal residue has been used for studying structure-function relationship of protein (Dixon and Fields 1972, Meth. Enzymol. 25, 409-419). We show that it is convenient for measuring the relative molecular masses of proteins by measuring the glycine formed from glyoxylate during such transamination. Quinoxaline derivatives have been synthesized by the reaction of 2-oxo acids from amino acids reacting with o-phenylenediamine. 2-Oxo acids transaminated from amino acids fluoresced at around 405 nm, depending on the nature of residual side groups. The emission maximum of 3-benzyl-2-hydroxy-quinoxaline from the reaction of o-phenylenediamine with phenylpyruvate was at 363 nm. The fluorescent derivatives have been used to study conformational changes of peptides and to detect whether or not N-termini of proteins were blocked.

Glycine↗