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Jianjun Zhang

Publications and source records attributed to Jianjun Zhang.

At least 37 records · Page 2Linked to original sources
PubMed2004

Food restriction in pregnant rat-like hamsters (Cricetulus triton) affects endocrine, immune function and odor attractiveness of male offspring.

We studied the effect of intrauterine food restriction (FR) on the immune function, endocrine status and attractiveness of scents of male rat-like hamsters, Cricetulus triton. Work was conducted on field-caught parents from the North China plain and their laboratory-born progeny. Restricted pregnant dams were fed 70% of the mean daily intake of hamsters with free access to food. FR caused a marked and protracted weight reduction of the body, adrenal, testes and epididymides in males. During the refeeding period, the spleen and thymus, but not the adrenal weight of the malnourished offspring caught up with that of the control after about 60 days. The present results demonstrated that estrous females preferred the odors of control males to that of FR males. Males whose mothers were food restricted during gestation had lower testosterone concentrations, immune responses and reproductive organ mass but had higher circulating cortisol than did the males in the control group. Thus, the effect of maternal FR may be an important cause in population regulation in the rat-like hamster. The testosterone level was positively correlated with immune function in rat-like hamsters, but the lower immunity was not suppressed by higher level of testosterone, as previously suggested. We also found a negative relationship between cortisol and immune function in the rat-like hamster.

Animals↗
PubMed2004

Facile synthesis of arabinomannose penta- and decasaccharide fragments of the lipoarabinomannan of the equine pathogen, Rhodococcus equi.

Pentasaccharide repeating unit 20 of the lipoarabinomannan from the equine pathogen, Rhodococcus equi, and its dimer 31, were synthesized. The pentasaccharide was obtained by assembling a benzoylated 2,6-branched mannosyl trisaccharide acceptor 13 with a free hydroxyl group at C-2' of the mannose residue attached to the core mannose residue by (1 --> 6)-linkage, followed by coupling with 2,3,5-tri-O-benzoyl-alpha-D-arabinofuranosyl-(1 --> 2)-3,4,6-tri-O-benzoyl-alpha-D-mannopyranosyl trichloroacetimidate (18), and by deacylation. Meanwhile, the decamer 31 was obtained by firstly preparing a benzoylated mannose (1 --> 6)-linked tetrasaccharide backbone 26 with 2-, 2"-O-ClAc, and 2'-, 2'''-O-Ac groups, respectively, then by dechloroacetylation and subsequent condensation with perbenzoylated trichloroacetimidate, and then by deacetylation and subsequent coupling with 18, and finally, by deacylation.

Acetamides↗
PubMed2004

Dietary protein intake and risk of osteoporotic hip fracture in elderly residents of Utah.

UNLABELLED: The role of protein intake in osteoporosis is unclear. In a case-control study in Utah (n = 2501), increasing level of protein intake was associated with a decreased risk of hip fracture in men and women 50-69 years of age but not in those 70-89 years of age. Protein intake may be important for optimal bone health. INTRODUCTION: Protein is an important component of bone, but the role of dietary protein intake in osteoporosis and fracture risk remains controversial. MATERIAL AND METHODS: The role of dietary protein intake in osteoporotic hip fracture was evaluated in a statewide case-control study in Utah. Patients, 50-89 years of age, with hip fracture (cases) were ascertained through surveillance of 18 Utah hospitals during 1997-2001. Age- and gender-matched controls were randomly selected. Participants were interviewed in their place of residence, and diet was assessed using a picture-sort food frequency questionnaire previously reported to give a useful measure of usual dietary intake in the elderly Utah population. The association between protein intake and risk of hip fracture was examined across quartiles of protein intake and stratified by age group for 1167 cases (831 women, 336 men) and 1334 controls (885 women, 449 men). RESULTS: In logistic regression analyses that controlled for gender, body mass index, smoking status, alcohol use, calcium, vitamin D, potassium, physical activity, and estrogen use in women, the odds ratios (OR) of hip fracture decreased across increasing quartiles of total protein intake for participants 50-69 years of age (OR: 1.0 [reference]; 0.51 [95% CI: 0.30-0.87]; 0.53 [0.31-0.89]; 0.35 [0.21-0.59]; p < 0.001). No similar associations were observed among participants 70-89 years of age. Results from analyses stratified by low and high calcium and potassium intake did not differ appreciably from the results presented above. CONCLUSION: Higher total protein intake was associated with a reduced risk of hip fracture in men and women 50-69 years of age but not in men and women 70-89 years of age. The association between dietary protein intake and risk of hip fracture may be modified by age. Our study supports the hypothesis that adequate dietary protein is important for optimal bone health in the elderly 50-69 years of age.

Age Factors↗
PubMed2004

A concise synthesis of two isomeric pentasaccharides, the O repeat units from the lipopolysaccharides of P. syringae pv. porri NCPPB 3364T and NCPPB 3365.

A concise synthesis of two isomeric pentasaccharides, alpha-L-Rhap-(1-->2)-alpha-L-Rhap-(1-->3)-alpha-L-Rhap-(1-->3)-[beta-D-GlcpNAc-(1-->2)]-alpha-L-Rhap (A) and alpha-L-Rhap-(1-->2)-alpha-L-Rhap-(1-->3)-[beta-D-GlcpNAc-(1-->2)]-alpha-L-Rhap-(1-->3)-alpha-L-Rhap (B), the O repeats from the lipopolysaccharides of Pseudonomonas syringae pv. porri NCPPB 3364T and 3365 was achieved via assembly of the building blocks, allyl 3,4-di-O-benzoyl-alpha-L-rhamnopyranoside (1), 2,3,4-tri-O-benzoyl-alpha-L-rhamnopyranosyl trichloroacetimidate (2), allyl 4-O-benzoyl-3-O-chloroacetyl-alpha-L-rhamnopyranoside (6), 3,4,6-tri-O-acetyl-2-deoxy-2-phthalimido-beta-D-glucopyranosyl trichloroacetimidate (7), and allyl 2,4-di-O-benzoyl-alpha-L-rhamnopyranoside (10). Coupling of 1 with 2 followed by deallylation and trichloroacetimidate formation gave the disaccharide donor 5, while condensation of 6 with 7, followed by dechloroacetylation, offered the disaccharide acceptor 9. Then, 5 was coupled with 10 to obtain the trisaccharide 11, and subsequent deallylation and trichloroacetimidate formation furnished the trisaccharide donor 13. Coupling of 9 with 13, followed by deprotection, afforded pentasaccharide 19, while condensation of 9 with 5, followed by deallylation and trichloroacetimidate formation, gave the tetrasaccharide donor 16, whose coupling with 10 and subsequent deprotection yielded another pentasaccharide 22.

Carbohydrate Sequence↗
PubMed2004

Synthesis of two oligosaccharides, the GPI anchor glycans from S. cerevesiae and A. fumigatus.

Two oligosaccharides, alpha-D-Manp-(1-->2)-alpha-D-Manp-(1-->2)-alpha-D-Manp-(1-->6)-alpha-D-Manp-(1-->4)-alpha-D-GlcpNAc (I) and alpha-D-Manp-(1-->3)-alpha-D-Manp-(1-->2)-alpha-D-Manp-(1-->2)-alpha-D-Manp-(1-->6)-alpha-D-Manp-(1-->4)-alpha-D-GlcpNAc (II), the glycosylphosphatidylinositol (GPI) anchor glycans from S. cerevesiae and A. fumigatus were synthesized as their methyl glycosides in a regio- and stereoselective manner. The pentasaccharide I was obtained from 6-O-selective glycosylation of methyl 2,3-di-O-benzoyl-alpha-D-mannopyranosyl-(1-->4)-2-acetamido-3,6-di-O-benzoyl-2-deoxy-alpha-D-glucopyranoside (8) with 2-O-acetyl-3,4,6-tri-O-benzoyl-alpha-D-mannopyranosyl-(1-->2)-3,4,6-tri-O-benzoyl-alpha-D-mannopyranosyl trichloroacetimidate (9), followed by benzoylation, deacetylation, and mannosylation, and then by deprotection. The hexasaccharide (II) was obtained via condensation of allyl 3,4,6-tri-O-benzoyl-alpha-D-mannopyranosyl-(1-->2)-3,4,6-tri-O-benzoyl-alpha-D-mannopyranoside (17) with 2,3,4,6-tetra-O-benzoyl-alpha-D-mannopyranosyl-(1-->3)-2,4,6-tri-O-acetyl-alpha-D-mannopyranosyl trichloroacetimidate (16), followed by deallylation, trichloroacetimidation, and coupling with acceptor (8), and finally by deprotection.

Acetylation↗
PubMed2004

[Influence of male surgical sterilization on social behavior of Brandt's vole].

Using the method of surgical sterilization, this paper studied the influence of sterilized male on the social behavior of Brandt's vole. The results showed that there was no significant difference in the frequency of amicable and agnostic behaviors between male surgical sterilization group and control, and between intact and sterilized males in the same group. It could be concluded that male surgical sterilization had no influence on the social behavior of Brandt's vole.

Animals↗
PubMed2003

A partial allelotyping of urothelial carcinoma of bladder in the Chinese.

The cancer spectrum and genetic pathways underlying tumorigenesis vary among different ethnic populations due to genetic background and/or environment discrepancies. We have implied in our previous study that the genetic alterations found in bladder cancers of Chinese patients differ from those of Caucasians. We performed the present study to explore the genetic pathways of the urothelial carcinoma (UC) in Chinese patients. We carried out a partial allelotyping of Chinese UC on chromosome arms commonly deleted in Caucasian UC, and compared the allelo-typing between Chinese and Caucasian UC. Forty-five Chinese UC specimens were allelotyped using 30 microsatellite markers on 18 chromosome arms. The most frequent regions of loss of heterozygosity found included 9q (54.1%), 17p (51.2%), 9p (48.8%), 18q (42.2%), 3p (41.9%), 16q (33.5%) and 11p (30.0%). Compared with UC from the UK and US, the LOH frequencies on most chromosome arms in this study are higher, with statistically significant differences on 3p, 16q and 18q. Our results suggest that both consensus and different alterations exist between Chinese and Caucasian UC, indicating that genetic alterations of cancer can vary between different ethnic populations due to genetic and/or etiological discrepancies.

Adult↗
PubMed2003

Efficient synthesis of a 3,6-branched mannose hepta- and octasaccharide.

Alpha-D-Manp-(1-->3)-[alpha-D-Manp-(1-->2)-alpha-D-Manp-(1-->6)]-alpha-D-Manp-(1-->3)-[alpha-D-Manp-(1-->2)-alpha-D-Manp-(1-->6)]-D-Manp and alpha-D-Manp-(1-->2)-alpha-D-Manp-(1-->3)-[alpha-D-Manp-(1-->2)-alpha-D-Manp-(1-->6)]-alpha-D-Manp-(1-->3)-[alpha-D-Manp-(1-->2)-alpha-D-Manp-(1-->6)]-D-Manp, were synthesized as their methyl glycosides in a regio- and stereoselective way.

Carbohydrate Conformation↗
PubMed2003

Facile syntheses of the hexasaccharide repeating unit of the exopolysaccharide from Cryptococcus neoformans serovar A.

Two hexasaccharides, beta-D-Xylp-(1-->2)-alpha-D-Manp-(1-->3)-[beta-D-Xylp-(1-->2)-]alpha-D-Manp-(1-->3)-[beta-D-GlcpA-(1-->2)-]alpha-D-Manp and beta-D-GlcpA-(1-->2)-alpha-D-Manp-(1-->3)-[beta-D-Xylp-(1-->2)-]alpha-D-Manp-(1-->3)-[beta-D-Xylp-(1-->2)-]alpha-D-Manp, the repeating unit of the exopolysaccharide from Cryptococcus neoformans serovar A, were synthesized as their methyl glycosides in a regio- and stereoselective manner.

Carbohydrate Conformation↗
PubMed2003

Synthesis of a hexasaccharide, the repeating unit of O-deacetylated GXM of C. neoformans serotype A.

beta-D-GlcpA-(1-->2)-alpha-D-Manp-(1-->3)-[beta-D-Xylp-(1-->2)]-alpha-D-Manp-(1-->3)[-beta-D-Xylp-(1-->2)]-alpha-D-Manp, the repeating unit of the exopolysaccharide from Cryptococcus neoformans serovar A, was synthesized as its allyl glycoside. Thus, 3-O-selective acetylation of allyl 4,6-O-benzylidene-alpha-D-mannopyranoside afforded 2, and subsequent glycosylation of 2 with 2,3,4-tri-O-benzoyl-D-xylopyranosyl trichloroacetimidate furnished the beta-(1-->2)-linked disaccharide 4. Debenzylidenation followed by benzoylation gave allyl 2,3,4-tri-O-benzoyl-beta-D-xylopyranosyl-(1-->2)-3-O-acetyl-4,6-di-O-benzoyl-alpha-D-mannopyranoside (5), and selective 3-O-deacetylation gave the disaccharide acceptor 6. Coupling of 6 with 2-O-acetyl-3,4,6-tri-O-benzoyl-alpha-D-mannopyranosyl trichloroacetimidate yielded the trisaccharide 8, and subsequent deallylation and trichloroacetimidation gave 2,3,4-tri-O-benzoyl-beta-D-xylopyranosyl-(1-->2)-[2-O-acetyl-3,4,6-tri-O-benzoyl-alpha-D-mannopyranosyl-(1-->3)]-4,6-di-O-benzoyl-alpha-D-mannopyranosyl trichloroacetimidate (9). Condensation of the trisaccharide donor 9 with the disaccharide acceptor 6 gave the pentasaccharide 10 whose 2-O-deacetylation gave the acceptor 11. Glycosylation of 11 with methyl 2,3,4-tri-O-acetyl-alpha-D-glucopyranosyluronate trichloroacetimidate and subsequent deprotection gave the target hexasaccharide.

Acetylation↗
PubMed2003

Efficient synthesis of a heptasaccharide, the repeating unit of the O-chain lipopolysaccharide produced by Xanthomonas campestris strain 642.

alpha-L-Rhap-(1-->3)-alpha-L-Rhap-(1-->2)-alpha-L-Rhap-(1-->3)-[beta-D-Xylp-(1-->2)-][beta-D-Xylp-(1-->4)-]alpha-L-Rhap-(1-->3)-alpha-L-Rhap, the repeating unit of the O-chain lipopolysaccharide produced by Xanthomonas campestris strain 642 was synthesized as its methyl glycoside via 3-O-selective glycosylation of methyl alpha-L-rhamnopyranosyl-(1-->3)-2,4-di-O-benzoyl-alpha-L-rhamnopyranoside (9) with 2,3,4-tri-O-benzoyl-alpha-L-rhamnopyranosyl-(1-->3)-2,4-di-O-benzoyl-alpha-L-rhamnopyranosyl-(1-->2)-3,4-di-O-benzoyl-alpha-L-rhamnopyranosyl trichloroacetimidate (8), followed by dixylosylation with 2,3,4-tri-O-benzoyl-alpha,beta-D-xylopyranosyl trichloroacetimidate (12) and subsequent deacylation.

Carbohydrate Sequence↗
PubMed2003

Identification of differentially expressed genes in immortalized human bronchial epithelial cell line as a model for in vitro study of lung carcinogenesis.

Suppression subtractive hybridization (SSH) was applied to identify differentially expressed genes in the SV40LT immortalized human bronchial epithelial cell line Y-BE, with normal human bronchial epithelial cells (HBEC) as a control. Two cDNA libraries of up- and downregulated genes were generated, comprising 218 known genes and 131 unknown genes in total. The expression of 22 clones from the 2 libraries was investigated by Northern blot analysis, and 86.4% (19/22) of them showed differential expression between Y-BE cells and HBEC. Although the Y-BE cells are nontumorigenic in nude mice, Comparative genomic hybridization (CGH) detected some DNA imbalances in Y-BE cells that were similar to lung cancer cells. Our data demonstrate that the studied cell line Y-BE and SSH is a reliable approach for identifying new genes that are associated with immortalization and early tumor development that may help to understand the pathogenesis of lung cancer.

Animals↗
PubMed2003

Synthesis of beta-D-GlcpNAc-(1-->3)-alpha-L-Rhap-(1-->2)-[beta-L-Xylp-(1-->4)]-alpha-L-Rhap-(1-->3)-alpha-L-Rhap, the repeating unit of the O-antigen produced by Pseudomonas solanacearum ICMP 7942.

An efficient synthesis of beta-D-GlcpNAc-(1-->3)-alpha-L-Rhap-(1-->2)-[beta-L-Xylp-(1-->4)]-alpha-L-Rhap-(1-->3)-alpha-L-Rhap, the repeating unit of the O-antigen produced by Pseudomonas solanacearum ICMP 7942 and its isomer beta-D-GlcpNAc-(1-->3)-alpha-L-Rhap-(1-->4)-[beta-L-Xylp-(1-->2)]-alpha-L-Rhap-(1-->3)-alpha-L-Rhap was achieved via sequential assembly of the building blocks, allyl 2,3-O-isopropylidene-alpha-L-rhamnopyranoside (2), allyl 3,4-O-isopropylidene-alpha-L-rhamnopyranoside (3), allyl 2,4-di-O-benzoyl-alpha-L-rhamnopyranoside (6), 3,4,6-tri-O-acetyl-2-deoxy-2-phthalimido-beta-D-glucopyranosyl trichloroacetimidate (7), and 2,3,4-tri-O-benzoyl-beta-L-xylopyranosyl trichloroacetimidate (12). The process was carried out in a regio- and stereoselective manner using glycosyl trichloroacetimidates as donors and unprotected or partially protected rhamnopyranosides as acceptors in the presence of a catalytic amount of trimethylsilyl trifluoromethanesulfonate (TMSOTf).

Carbohydrate Conformation↗
PubMed2003

Synthesis of a mannose heptasaccharide existing in baker's yeast, Saccharomyces cerevisiae X2180-1A wild-type strain.

A mannose heptasaccharide existing in baker's yeast, Saccharomyces cerevisiae X2180-1A wild-type strain, was effectively synthesized as its allyl glycoside via TMSOTf-promoted condensation of a disaccharide donor 13 with a pentasaccharide acceptor 12, followed by deprotection. The pentasaccharide 12 was constructed by coupling of 2,3,4,6-tetra-O-benzoyl-alpha-D-mannopyranosyl-(1-->3)-2,4,6-tri-O-benzoyl-alpha-D-mannopyranosyl-(1-->2)-3,4,6-tri-O-benzoyl-alpha-D-mannopyranosyl-(1-->2)-3,4,6-tri-O-benzoyl-alpha-D-mannopyranosyl trichloroacetimidate (9) with allyl 6-O-acetyl-3,4-di-O-benzoyl-alpha-D-mannopyranoside (10), followed by deacetylation. The tetrasaccharide 9 was obtained by coupling of 2,3,4,6-tetra-O-benzoyl-alpha-D-mannopyranosyl-(1-->3)-2,4,6-tri-O-benzoyl-alpha-D-mannopyranosyl trichloroacetimidate (5) with allyl 3,4,6-tri-O-benzoyl-alpha-D-mannopyranosyl-(1-->2)-3,4,6-tri-O-benzoyl-alpha-D-mannopyranoside (6), followed by deallylation and trichloroacetimidation. The disaccharides 6 and 13 were readily obtained by known methods.

Carbohydrate Sequence↗
PubMed2003

Egg consumption and mortality from colon and rectal cancers: an ecological study.

The relation between egg consumption and mortality from colon and rectal cancers remains unclear and was investigated in this study. Colon and rectal cancer mortality data, mostly around 1993-94 and egg consumption data in nine time periods (1964-94) in 34 countries were derived from World Health Organization and Food and Agriculture Organization, respectively. Egg consumption was significantly and positively correlated with mortality from colon and rectal cancers in both sexes in most of the nine time periods. The correlations were generally stronger for colon cancer (r = 0.39 to 0.63 in men and r = 0.33 to 0.65 in women) than for rectal cancer (r = 0.18 to 0.49 in men and r = 0.08 to 0.45 in women). After adjustment for confounding factors, egg consumption was still significantly and positively associated with mortality from colon cancer in the earliest five time periods (1964-84) (P = 0.046 to 0.017 in men and P = 0.034 to 0.014 in women) and rectal cancer in the latest five time periods except for the last time period (1982-91) (P = 0.046 to 0.024 in men and P = 0.045 to 0.026 in women). This study suggested that egg consumption was associated with an increased risk of colon and rectal cancers at the population level

Agriculture↗
PubMed2002

Deletion of tumor suppressor genes in Chinese non-small cell lung cancer.

In the present study, we used 22 microsatellite markers flanking to or within 13 known or candidate tumor suppressor genes (TSGs) to detect loss of heterozygosity (LOH) in these chromosomal regions among 41 cases of non-small cell lung cancer, including 28 squamous cell carcinoma (SCC) and 13 adenocarcinoma (ADC). The studied TSGs comprised FHIT, VHL, APC, PRLTS, p16, IFNA, PTEN, p57, ATM, p53, BRCA1, DPC4 and DCC. Our data demonstrated frequent allelic losses of FHIT, p53, IFNA, VHL and p16 in both SCC and ADC. PTEN and ATM showed the least frequency of LOH, while no deletion of BRCA1 was detected in all tumor samples. LOH analysis of PRLTS was extended to 26 cases of ADC, which demonstrated significantly higher frequency of LOH than SCC. Our data indicated a possible correlation between specific TSG(s) and either histological type of lung cancer, and more attention should be paid to the PRLTS gene, which might play an important role in the development of ADC.

Adenocarcinoma↗
PubMed2002

[Loss of heterozygosity of tumor suppressor genes at chromosome 3p in transitional cell carcinoma of urinary bladder].

OBJECTIVE: To investigate the potential effects of three tumor suppressor genes located at chromosome 3p, FHIT, hMLH1 and VHL, in carcinogenesis of transitional cell carcinoma (TCC) of urinary bladder in Chinese. METHODS: PCR was used to examine the heterozygosity and loss of heterozygosity (LOH) of the 6 microsatellite polymorphic markers inside of or flanking to the three genes tumor suppressor genes FHIT, hMLHi, and VHL in TCC tissues of 40 cases. RESULTS: The rates of heterozygosity and LOH were 55.0% (38/40) and 59.1% (22/38) for hMLH1 gene. The rates of heterozygosity and LOH were 90.0% (36/40) and 47.2% (17/36). The rate of heterozygosity of the two microsatellite polymorphic markers in the intron of FHIT gene, D2S1234 and D3S1300, were 70% (28/40) and 67.5% (27/40), The LOH rates of D2S1234 and D3S1300 were 46.4% (13/28) and 37% (10/27) respectively. The rate that at least one the these 2 microsatellite polymorphic markers was heterozygote was 95.0% (38/40), the rate that LOH occurred for at least one of them was 57.8% (22/38). The heterozygosity rate of D3S1561 and D3S1612, two microsatellite polymorphic markers linked to hMLH1 gene, were 42.5% (17/40) and 30% (12/40) respectively, the LOH rates for these two markers were 41.2% (7/17) and 75.0% (9/12) respectively, the rate that at least one of these two markers was heterozygote was 59.1% (13/22). The heterozygosity rate of D3S10368 and D3S1284, two microsatellite polymorphic markers linked to VHL gene, were 70% (28/40) and 47.5% (19/40) respectively, the LOH rates for these two markers were 42.8% (12/28) and 42.1% (8/19) respectively, the rate that at least one of these two markers was heterozygote was 90.0% (36/40). High frequencies of LOH were found in tumor suppressor genes FHIT, hMLH1 and VH. Only the LOH of D3S1284 was positively correlated with the pathological staging of TCC of urinary bladder (P < 0.05). CONCLUSION: LOH in tumor suppressor genes FHIT, hMLH1 and VHL may play an important role in carcinogenesis of human urinary bladder, and may provide new approaches for early detection of TCC. Loss of VHK gene may be a late event of carcinogenesis of TCC.

Acid Anhydride Hydrolases↗