Biomedical subjects
Publications and source records attributed to Jian Zheng.
Chen et al. identified 132 whole-genome duplications (WGDs) clustered around environmental crises. We highlight how, over longer evolutionary timescales, ancient WGDs convergently retained MADS-box, MYB, WRKY and HSF transcription factors, building stress-adaptation networks. These insights guide climate-resilient crop improvement through comparative genomics and CRISPR engineering.
Five germacrane-type sesquiterpene alcohols obtained from curdione (1) by microbial biotransformation were isolated. Their structures were characterized as (2R)-2beta-hydroxycurdione (2), 1alpha, 10beta-epoxy-11-hydroxycurdione (3), (2S)-2alpha, 11-dihydroxycurdione (4), 11,15-dihydroxycurdione (5) and (3R)-3alpha-hydroxycurdione (6) based on the extensive NMR studies. Among them, 4, 5 and 6 are new compounds.
BACKGROUND: One of the major characteristics of the human immunodeficiency virus type 1 (HIV-1) is its unusually high degree of genetic variability, which involves in genetic diagnosis, subtyping, vaccine design, and epidemiology. HIV-1 CRF01_AE is a main prevalent HIV-1 recombinant strain in China. In this study, three full-length CRF01_AE genomes from Fujian Province, China were cloned, sequenced, and analyzed; and the further genetic diversity defining and epidemiologic analysis were carried out. METHODS: Proviral DNA was extracted from non-cultured peripheral blood mononuclear cells, the near full-length HIV-1 genome was amplified and the PCR products were cloned into pCR-XL-TOPO vector and sequenced. 5'-long terminal repeat (LTR) and 3'-LTRs were amplified by additional independent PCR and cloned into pMD18T vector. Gene-based phylogenic tree was constructed and genetic distances were calculated by MEGA 3.1. Simplot was used for Bootscan analysis. RESULTS: The phylogeny and genetic distance analysis of the three near full-length sequences confirmed that these three samples clustered with CRF01_AE isolates, more close to Thailand CRF01_AE strain CM240, and were distantly related to African CRF01_AE strain 90CF402. Analysis of their genomic organization revealed the presence of nine potential open reading frames. There were no major deletions, rearrangements, or insertions in the three sequences, but an in-frame stop codon was found in tat gene of Fj051. LTRs of the three sequences contained a few nucleotides mutation. We did not find new mosaic recombinant in the three sequences. The V3 motif was GPGQ in all the three sequences, and there were only few amino acids differences in all three V3 loop sequences. CONCLUSION: This report reveals the background of the three full-length CRF01_AE genomes, the most dominantly circulating HIV-1 strain in Fujian Province, China. The work is essential for the design and development of an effective AIDS vaccine for the region.
Porous fiber membranes consisting of 1D assemblies of ZnO nanocrystal-supported poly(vinyl alcohol) (PVA) nanofibers are described. These hybrid nanofiber membranes were assembled by first electrospinning a ZnO precursor-containing PVA aqueous solution. Subsequently, the electrospun composite nanofibers were submerged in a basic ethanol solution. As a result, ZnO precursors in solid PVA matrixes were hydrolyzed to generate ZnO crystals residing on the fiber surfaces. Photoluminescence spectroscopy analysis demonstrated the as-hydrolyzed fiber membranes possess white luminescence. Furthermore, the ZnO-encapsulated PVA nanofibers were prepared by directly electrospinning a ZnO nanocrystal-containing PVA solution as the contrast of the as-hydrolyzed hybrid nanofibers. The surface photovoltage spectroscopy (SPS) confirmed that the as-hydrolyzed hybrid fiber membranes had a strong SPS response, but the directly spun fiber membranes did not have any SPS response. This can be attributed to the favorable structure of the hydrolyzed hybrid nanofibers, that is, the surface residence of ZnO permits ZnO crystals to make direct contact with ITO electrodes to transfer the photogenerated electron originating from ZnO to ITO electrodes. By contrast, the transfer of the photogenerated electron is limited by PVA matrixes in the directly spun fiber system.
Large-volume seawater samples were collected in the Sulu and South China Seas and their (137)Cs activities were determined by gamma-ray spectrometry using a low background type high-purity Ge detector. Vertical distributions of (137)Cs activity showed an exponential decrease in the South China Sea, whereas a subsurface maximum at 200m depth and monotonic decrease below 300m were observed in the Sulu Sea. A significant difference in intermediate water (137)Cs activities in the 500-2000m depth was observed between the Sulu and South China Seas, i.e., the (137)Cs activities in the Sulu Sea were remarkably higher than those in the South China Sea. The difference in the (137)Cs inventory below 500m was approximately 1200Bqm(-2) between the Sulu and South China Seas. The (137)Cs total inventory of 3200Bqm(-2) in the Sulu Sea was 5.7 times higher than that expected from global fallout. A possible mechanism controlling this extremely high (137)Cs total inventory may be inflows of the (137)Cs rich water masses through the Luzon Strait, lateral transport across the Mindoro Strait into the Sulu Sea, and then subduction into the deep layer in the basin.
We examined the vertical distributions of 239+240Pu activity and 240Pu/239Pu atom ratio in settling particles and quantified the particulate 239+240Pu fluxes in the water column in the western Northwest Pacific. Settling particle samples were collected using sediment traps. Plutonium isotopes were analyzed using a sector field high-resolution ICP-MS. To the best of our knowledge, this is the first time that both Pu activity and Pu isotope ratio data have been obtained for settling particles in the Pacific Ocean. The high (>0.18) 240Pu/239Pu atom ratios in settling particles indicate that plutonium from the Pacific Proving Grounds (PPG) source in the central Pacific is transported toward the western Northwest Pacific. Evidence indicates that Pu scavenging onto the settling particles is strongly dependent upon the bulk mass flux. The results suggest that advective lateral transport of dissolved Pu from the open ocean to the ocean margin and removal of Pu into the margin sediments by particle scavenging is a common phenomenon in the Pacific Ocean. Plutonium can be considered as a useful tracer to study the transport and fate of other contaminants that readily adsorb to particles in marine environments.
Three new triterpenoid saponins, julibroside J(29) (1), julibroside J(30) (2), and julibroside J(31) (3), were isolated from the stem bark of Albizia julibrissin Durazz. (Leguminosae) by using chromatographic method. Their structures were established by spectroscopic methods. Compounds 1, 2, and 3 displayed significant anti-tumor activities in vitro against PC-3M-1E8, HeLa, and MDA-MB-435 cancer cell lines at 10microM assayed by SRB and MTT methods.
OBJECTIVE: To seek the pathomorphological targets for forensic expertise in anaphylactic shock. METHODS: The expression of IgE in hearts, lungs, livers, spleens, kidneys, gastrics, intestinals, tracheas and tonsils of anaphylactic shock guinea-pigs was observed at 0, 6, 12 h and 24 h respectively by tissue chip S-P immuno-histochemical method. RESULTS: Positive expression of IgE presented in lungs and tracheas in the test group with the peak at 0 hour and it declined as time advanced, and also there were significant differences at different times (P<0.05). CONCLUSION: The immuno-histochemical method of detecting the expression of IgE in lungs, tracheas and spleens can be supposed to be the pathomorphological targets for forensic expertise in anaphylactic shock. The weakening of the positive expression of IgE in lungs and tracheas as the time advanced suggested that in this kind of case the autopsy should be arried out as early as possible.
AIM: To prepare monoclonal antibody (mAb) against Vibrio cholerae O139, which would be used as the gold colloidal reagent strip for rapid detection of O139, and to determine its biological characterization. METHODS: BALB/c mice were immunized by inactivated Vibrio cholerae O139. Anti-O139 mAbs were prepared by using hybridoma technique. The specificity of mAb was determined by indirect ELISA and Western blot. The indirect ELISA was used to identify Ig subgroup, detect its titer in ascites and relative affinity, and analyze antigen-binding epitope of mAbs. RESULTS: Two hybridoma cells (O4D7 and O4D10), secreting anti-O139 mAbs were obtained. The Ig subgroups of O4D7 and O4D10 were IgG2b and IgG3, respectively. The mAb's titer in ascites was 1:10(7). The relative affinity of mAb O4D7 was more than 10(5) and that of O4D10 was more than 10(4). The result of additive ELISA showed that two mAbs could recognize different antigen epitopes. CONCLUSION: The successful preparation of two anti-O139 mAbs provides a powerful tool for the development of a rapid method of detecting Vibrio cholerae O139 infection.
OBJECTIVE: To study the chemical constituents of Mentha spicata. METHOD: The chemical constituents were isolated by silica gel column chromatography, and identified by physical and chemical characters and spectroscopic analysis. RESULT: Compounds I - V were obtained and their structures were elucidated as protocatechuic aldehyde (I), protocatechuic acid (II), chrysoeriol (III), 5, 6-dihydroxy-7, 8, 3', 4'-tetramethoxyflavone (IV), nodifloretin (V). CONCLUSION: Compound I and II were first isolated from the genus Mentha. Compound Ill, IV and V were isolated from M. spicata for the first time.
AIM: To study the effect of antiparallel phosphorothioate triplex-forming oligonucleotide (apsTFO) matching with the shear stress response element (SSRE) of tissue factor (TF) gene promoter region on the expression of TF in endothelial cells (ECs) of rat common carotid artery stenosis. METHODS: The model of common carotid artery middle segment stenosis was established by silica gel pipe loop ligation in SD rats. The mRNA expression and protein synthesis of TF, early growth response-1 (Egr-1) and specificity protein 1 (Sp1) were measured by in situ hybridization (ISH) and immunohistochemistry (IHC) technique. GT21-apsTFO, GT20-apsTFO, GT20-psTFO and FITC-labeled apsTFO, matching with the SSRE of TF gene promoter region, were designed, and intravenously injected into rats at 0.5 h before operation. TFO was detected 4 h after the operation, and the mRNA expression and protein synthesis of TF, Egr-1 and Sp1 were detected 6 h after the operation. RESULTS: There were much fluorescence in vascular tissue, especially in the nuclear of ECs 4.5 h after the injection of apsTFO. The mRNA expression and protein synthesis of TF reduced by 22% - 23% with injection of GT20-apsTFO 6.5 h after stenosis (P < 0.01) and by 10% - 11% with GT21-apsTFO at the same time (P < 0.05). The inhibition by GT20-apsTFO was stronger than that of the GT21-apsTFO (P < 0.05). The expression of TF was not inhibited by the GT20-psTFO (P > 0.05). The mRNA expression and protein synthesis of Egr-1 and Sp1 did not change in the rat treated with GT20-apsTFO, GT20-psTFO and GT21-apsTFO (P > 0.05). CONCLUSION: apsTFO could mero-inhibit the expression of TF gene but could not change the expression of Egr-1 and Sp1 protein.
A [(3)H]batrachotoxinin A-20alpha-benzoate ([(3)H]BTX-B) binding assay was used to investigate the interaction of two ginseng aglycones (20(S)protopanaxadiol and 20(S)protopanaxatriol) and Rh(2) (a monoglucoside of 20(S)protopanaxadiol) with voltage-gated sodium channels in mouse brain. All compounds inhibited the binding of [(3)H]BTX-B and IC(50)s were established at 42 microM (20(S)protopanaxadiol), 79 microM (20(S)protopanaxatriol) and 162 microM (Rh(2)). Scatchard analysis confirmed that 20(S)protopanaxadiol and Rh-2 reduced the B(max) of [(3)H]BTX-B binding while Rh(2) also increased the K(d). At IC(50) concentrations and above, 20(S)protopanaxadiol and Rh(2) increased the dissociation of the [(3)H]BTX-B:sodium channel complex above that produced by a saturating concentration of veratridine, but failed to reduce the rate of association of [(3)H]BTX-B with sodium channels. Reversal of the inhibition of [(3)H]BTX-B binding by 20(S)protopanaxadiol and Rh(2) occurred slowly. We conclude that the 20(S)protopanaxadiol and the less potent inhibitor Rh(2) destabilize BTX-B-activated sodium channels through non-covalent allosteric modification of neurotoxin binding site 2.
OBJECTIVE: To study the relationship between the change of N2 wave in flash visual evoked potentials (fVEP) and the intracranial pressure after the administration of mannitol. METHODS: Fifty-two patients with elevated intracranial pressure were chosen and are divided into two groups: the former (n = 32) were treated with mannitol, the latter (n = 20) were treated with mannitol and glycerol and sodium chloride injection. The latency and amplitude of N2 wave of fVEP was measured by NIP-200 noninvasive intracranial pressure apparatus before and after the 1st, 4th, 10th administration of mannitol. RESULTS: The latency of N2 wave began to reduce at 30 min after the injection of mannitol and was lowest at 2 h. At 4 h after the injection of mannitol, the latency of N2 wave increased but was still shorter than that before the injection of mannitol. The amplitude of N2 wave did not change significantly. The reduction of the latency of N2 wave after the administration of mannitol decreased with the multiple mannitol injection. The latency of N2 wave did not change significantly after the administration of mannitol when combined with glycerol and sodium chloride injection. CONCLUSION: The latency of N2 wave of fVEP changes after the administration of mannitol, which suggests that the change of the latency of N2 wave of fVEP can reflect the change of intracranial pressure.
Surface seawater samples were collected along the track of the R/V Hakuho-Maru cruise (KH-96-5) from Tokyo to the Southern Ocean. The (137)Cs activities were determined for the surface waters in the western North Pacific Ocean, the Sulu and Indonesian Seas, the eastern Indian Ocean, the Bay of Bengal, the Andaman Sea, and the South China Sea. The (137)Cs activities showed a wide variation with values ranging from 1.1 Bq m(-3) in the Antarctic Circumpolar Region of the Southern Ocean to 3 Bq m(-3) in the western North Pacific Ocean and the South China Sea. The latitudinal distributions of (137)Cs activity were not reflective of that of the integrated deposition density of atmospheric global fallout. The removal rates of (137)Cs from the surface waters were roughly estimated from the two data sets of Miyake et al. [Miyake Y, Saruhashi K, Sugimura Y, Kanazawa T, Hirose K. Contents of (137)Cs, plutonium and americium isotopes in the Southern Ocean waters. Pap Meteorol Geophys 1988;39:95-113] and this study to be 0.016 yr(-1) in the Sulu and Indonesian Seas, 0.033 yr(-1) in the Bay of Bengal and Andaman Sea, and 0.029 yr(-1) in the South China Sea. These values were much lower than that in the coastal surface water of the western Northwest Pacific Ocean. This was likely due to less horizontal and vertical mixing of water masses and less scavenging. (239+240)Pu activities and (240)Pu/(239)Pu atom ratios were also determined for the surface waters in the western North Pacific Ocean, the Sulu and Indonesian Seas and the South China Sea. The (240)Pu/(239)Pu atom ratios ranged from 0.199+/-0.026 to 0.248+/-0.027 on average, and were significantly higher than the global stratospheric fallout ratio of 0.18. The contributions of the North Pacific Proving Grounds close-in fallout Pu were estimated to be 20% for the western North Pacific Ocean, 39% for the Sulu and Indonesian Seas and 42% for the South China Sea by using the two end-member mixing model. The higher (240)Pu/(239)Pu atom ratios could be attributed to close-in fallout Pu delivered from the Enewetak and Bikini Atolls by ocean currents of branches of the North Equatorial Current to the Southeast Asian seas.
The objectives of the present work were to study isotope ratios and the inventory of plutonium and uranium isotope compositions in sediments from Lake Obuchi, which is in the vicinity of several nuclear fuel facilities in Rokkasho, Japan. Pu and its isotopes were determined using sector-field ICP-MS and U and its isotopes were determined with ICP-QMS after separation and purification with a combination of ion-exchange and extraction chromatography. The observed (240)Pu/(239)Pu atom ratio (0.186 +/- 0.016) was similar to that of global fallout, indicating that the possible early tropospheric fallout Pu did not deliver Pu from the Pacific Proving Ground to areas above 40 degrees N. The previously reported higher Pu inventory in the deep water area of Lake Obuchi could be attributed to the lateral transportation of Pu deposited in the shallow area which resulted from the migration of deposited global fallout Pu from the land into the lake by river runoff and from the Pacific Ocean by tide movement and sea water scavenging, as well as from direct soil input by winds. The (235)U/(238)U atom ratios ranged from 0.00723 to 0.00732, indicating the natural origin of U in the sediments. The average (234)U/(238)U activity ratio of 1.11 in a sediment core indicated a significant sea water U contribution. No evidence was found for the release of U containing wastes from the nearby nuclear facilities. These results will serve as a reference baseline on the levels of Pu and U in the studied site so that any further contamination from the spent nuclear fuel reprocessing plants, the radioactive waste disposal and storage facilities, and the uranium enrichment plant can be identified, and the impact of future release can be rapidly assessed.
The vertical distributions of 239+240Pu-specific activities and 240Pu/239Pu atom ratios in sediment cores of the Japan Sea were investigated. For comparison, the 239+240Pu-specific activities and 240Pu/239Pu atom ratios in the surface layer of bottom sediments in the Sea of Okhotsk were also determined. The 239+240Pu-specific activities in the surface layer sediments varied from 0.43 to 2.65 mBq/g in the Japan Sea. The lowest value was seen in the eastern Japan Basin, while the highest value was found in a sample collected from a coastal area off Hokkaido in the northern Japan Sea. It was found that the 240Pu/239Pu atom ratios in the surface sediments for the Japanese side of the Japan Sea ranged from 0.15 to 0.22. The 240Pu/239Pu atom ratios in the surface sediments collected from the Yamato Basin and Japan Basin were typically close to the global fallout value of 0.18, but higher 240Pu/239Pu atom ratios (0.20-0.22) were seen in samples from the northern Japan Sea. Vertical profiles of 240Pu/239Pu atom ratios revealed that these atom ratios were higher than the global fallout value in the deeper layers in the sediment cores from the northern Japan Sea on the Hokkaido coast and the Yamato Basin. In addition, the sediment cores from the northern Japan Sea near the Soya Strait and in the Ishikari Estuary had a constant vertical distribution of 240Pu/239Pu atom ratios with a value around 0.20. The results obtained in this work support the hypothesis that the prevailing ocean currents transported Pu derived from the Pacific Proving Grounds to the Japan Sea, and this contributed to the general elevated Pu inventory in the Japan Sea.
Aged individuals experience the highest rate of stroke and have less functional recovery, but do not have larger infarcts. We hypothesized that aged individuals experience greater sublethal damage in peri-infarct cortex. Focal cortical stroke was produced in aged and young adult animals. After 30 min, 1, 3 and 5 days brain sections and Western blot were used to analyze markers of apoptotic cell death, oxidative DNA and protein damage, heat shock protein (HSP) 70 induction, total neuronal number and infarct size. Focal stroke produces significantly more oxidative DNA and protein damage and fewer cells with HSP70 induction in peri-infarct cortex of aged animals. There is no difference in infarct size or the number of cells undergoing apoptosis between aged and young adults. Stroke in the aged brain is associated with a greater degree of DNA and protein damage and a reduced stress response in intact, surviving tissue that surrounds the infarct.
BACKGROUND & OBJECTIVE: Platinum-based chemotherapy regimens are better than other regimens when treating patients with advanced non-small cell lung cancer (NSCLC). The third generation of platinum-based regimens {NP [Navelbine (NVB), cisplatin (DDP)], TP (Taxol, DDP), GP (Gemzar, DDP)} is better than the second generation {MVP [mitomycin (MMC), desacetylvinblastin amide (VDS), DDP], MIP [MMC, ifosfamide (IFO), DDP], EP [etopside (VP-16), DDP], VDS+DDP}. This study was to compare the efficacy between the second and the third generations of platinum-based regimens combined with radiotherapy on advanced non-small cell lung cancer (NSCLC). METHODS: From Jul. 1999 to Dec. 2001, 47 pathologically confirmed advanced NSCLC patients received chemoradiotherapy: 24 received the second generation of platinum-based regimens, 23 received the third generation; all patients received routine external irradiation of (60)Co (65-76 Gy). Characteristics of the patients were comparable. Kaplan-Meier analysis was used to evaluate survival rates, and log-rank test to study differences between the 2 groups. RESULTS: The objective response rates were 41.7% in the second generation group, and 56.5% in the third generation group (Chi (2)=0.53, P=0.47). The median time to progression and median survival time were significantly longer in the third generation group than in the second generation group (12.6 months vs. 6.0 months, Chi(2)=6.93, P=0.01; 14.0 months vs. 9.0 months, Z=-2.17, P=0.03). The 1-, and 2-year survival rates were significantly higher in the third generation group than in the second generation group (56.3% vs. 30.7%, 15.6% vs. 0%, Chi(2)=6.59, P=0.01). The major adverse events were leukocytopenia, nausea and vomiting, radiation-induced esophagitis and pneumonia, which were tolerable. CONCLUSIONS: The third generation of platinum-based regimens in combination with radiotherapy for advanced non-small lung cancer may be more advantageous over the second generation of platinum-based regimens in prolonging survival of advanced NSCLC patients, which would be worth being studied further.