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Xu Q, Liu ZH, Fang SF. [Retrieval method for estimating snow depth using hyperspectral data in snowmelt period]. GUANG PU XUE YU GUANG PU FEN XI = GUANG PU 2013; 33:1927-1931. [PMID: 24059203] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
The snow surface reflectance spectra with different depth in snowmelt period and snow depth data were measured and its correlation was analyzed. The characteristic absorption band data of the valley with higher correlation were used to establish a single band snow depth regression model. The highest contribution rate of the band was selected as the input variable of the neural network model to retrieve snow depth. The results show that in Juntang Lake area, near 1 022, 1 241 and 1 492 nm exists characteristic absorption valley of snow, and compared to estimation accuracy of the single-band inversion of snow depth model (R2 = 0.53), ANN-BP model has a higher inversion level, and determination coefficient (R2 = 0.86, RMSE = 0.67) was obtained with 4 nodes in hidden layers, indicating that ANN-BP model can greatly improve the ability of inversion of snow depth with hyperspectral data.
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Su ZH, Gan J, Yu QK, Zhang QH, Liu ZH, Bao JM. High-resolution fiber optic temperature sensors using nonlinear spectral curve fitting technique. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2013; 84:045002. [PMID: 23635225 DOI: 10.1063/1.4802684] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
A generic new data processing method is developed to accurately calculate the absolute optical path difference of a low-finesse Fabry-Perot cavity from its broadband interference fringes. The method combines Fast Fourier Transformation with nonlinear curve fitting of the entire spectrum. Modular functions of LabVIEW are employed for fast implementation of the data processing algorithm. The advantages of this technique are demonstrated through high performance fiber optic temperature sensors consisting of an infrared superluminescent diode and an infrared spectrometer. A high resolution of 0.01 °C is achieved over a large dynamic range from room temperature to 800 °C, limited only by the silica fiber used for the sensor.
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Zhuo FL, Sun ZG, Li CY, Liu ZH, Cai L, Zhou C, Zhang JZ. Clinical isolates of Mycobacterium abscessus in Guangzhou area most possibly from the environmental infection showed variable susceptibility. Chin Med J (Engl) 2013; 126:1878-1883. [PMID: 23673103] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/02/2023] Open
Abstract
BACKGROUND Mycobacterium abscessus (M. abscessus) can cause a variety of human infections, involving the lung, skin and soft tissues, and is generally believed to be acquired from environmental sources. The aim of this study was to investigate the molecular diversity and antibiotic susceptibility of M. abscessus isolates as the basis for strategies to improve control and management of infection. METHODS Seventy M. abscessus isolates from patients attending the Guangzhou Thoracic Hospital were identified from 2003 to 2005 by biochemical tests, gas chromatography, polymerase chain reaction (PCR)-restriction analysis (PRA) of heat shock protein gene hsp65, and sequencing of the quinolone resistance determining regions (QRDRs) of gyrA. Susceptibilities to six antibiotics were determined by micro-broth dilution. Isolates were genotyped using randomly amplified polymorphic DNA (RAPD) analysis. RESULTS Most isolates (63/70; 90%) were susceptible to amikacin but rates of susceptibility to other antibiotics varied from moderate, clarithromycin (60%) and imipenem (43%), to low for ciprofloxacin and ofloxacin (3%), and 87% of isolates had intermediate susceptibility to cefoxitin. RAPD analysis showed that the 70 clinical isolates displayed 69 unique RAPD patterns. CONCLUSIONS The high genetic diversity of isolates suggests that they are not transmitted from person to person but, presumably, are acquired independently from environmental sources. M. abscessus isolates displayed variable levels of susceptibility to all antibiotics tested, other than amikacin, indicating a need for routine susceptibility testing to guide treatment.
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Li YQ, Pan QJ, Liu ZH, Hu XH, Liao XL, Huang SQ. Efficacy of intraperitoneal versus intravenous pemetrexed administration in management of malignant ascites in mice bearing ascitic hepatoma-22. Shijie Huaren Xiaohua Zazhi 2012; 20:3767-3772. [DOI: 10.11569/wcjd.v20.i36.3767] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
AIM: To compare the effectiveness of intraperitonea and intravenous administration of pemetrexed (PEM) in the management of malignant ascites in mice bearing hepatoma-22 (H22).
METHODS: A mouse model of ascites was established by intraperitoneal injection of 0.2 mL of H22 cell suspension (at a density of 1 × 107/mL cells). The mice were randomly divided into three groups at random on day 5 after induction of ascites (n = 18 per group): normal control group (normal saline), intraperitoneal pemetrexed group (PEM 300 mg/kg), and intravenous pemetrexed group (PEM 300 mg/kg). Pemetrexed was injected intraperitoneally or intravenously on days 5 and 8. The body weight, abdomen circumference and behavior of the mice were measured daily. Eight mice of each group were sacrificed on day 11 to measure the volume of ascites. The survival time of rest mice were recorded.
RESULTS: The mean volumes of ascites in the normal control group, intraperitoneal pemetrexed group and intravenous pemetrexed group were 15.74 mL ± 1.71 mL, 13.31 mL ± 2.45 mL and 8.58 mL ± 1.89 mL, respectively. In comparison to the normal control group, the two pemetrexed treatment group had significantly less production of ascites in (both P < 0.05). The mean volume of ascites in the intraperitoneal pemetrexed group was significantly lower than that in the intravenous administration group (P < 0.01). The mean survival times of mice in the intraperitoneal pemetrexed group, intravenous pemetrexed group, and normal control group were 15.10 d ± 0.46 d, 17.90 d ±0.71 d, and 14.20 d ± 0.44 d, respectively. The survival time was prolonged by 6.34% and 26.06% in the intraperitoneal pemetrexed group and intravenous pemetrexed group compared to the normal control group. There was no significant difference in the survival time between the intraperitoneal pemetrexed group and normal control group (P > 0.05), but the mean survival time was significantly longer in the intravenous pemetrexed group than in the normal control group and intraperitoneal pemetrexed group (both P < 0.01).
CONCLUSION: Intraperitoneal administration of pemetrexed is not superior to traditional intravenous administration in the management of malignant ascites in mice bearing ascitic hepatoma-22.
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Abstract
Pancreatic cancer is a disease that seriously threatens the health of human beings. The treatment options currently available for pancreatic cancer are still limited. In this article, we describe the principle of whole body gamma knife and SBRT (a treatment similar to whole body gamma knife) for the treatment of advanced pancreatic cancer. By improving the absorbed dose in the lesion, whole body gamma knife can control tumor progression and improve survival in patients with pancreatic cancer with low side effects. Despite that controversy still exists, the advantages of SBRT in the treatment of pancreatic cancer have been gradually recognized in foreign countries.
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Zhao YZ, Liu ZH. First Report of Black Spot Disease Caused by Alternaria alternata on Cherry Fruits in China. PLANT DISEASE 2012; 96:1580. [PMID: 30727320 DOI: 10.1094/pdis-04-12-0416-pdn] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Cherry (Cerasus pseudocerasus) has become an economically important fruit in China in recent years. In June 2010, fruit spots were discovered on fruit grown in Dalian City, Liaoning Province, China and 30% of local-orchard trees were infected with the disease, reducing yield and fruit quality. Disease incidence increased up to 75% in 2011. At the initial stage of the infection, some small, light brown spots appeared on the fruit that gradually became round or irregular and dark brown, and a black-brown concentric ring formed in the advanced stage of the infection. As disease progressed, the lesions expanded, causing the fruit surface to become pitted, withered, and dead. The pathogen was isolated from infected fruit of four orchards by a tissue isolation method (1) and cultured on potato dextrose agar (PDA) at 25°C in the dark for one week. Colonies on PDA were initially white and became grayish brown over time. Conidiophores were single or fasciculate, straight or knee curved, gray-brown with regular septa, branched or unbranched, and 12.5 to 90.0 × 2.0 to 5.0 μm. Conidia were oval, obclavate, or obpyriform, brown or dark brown, surface smooth or spinulose with short columnar beaks, and 20.0 to 42.0 × 7.5 to 14.5 μm with three to eight transverse septa and zero to three longitudinal or oblique septa. The sporulation pattern appeared in bush branches. According to the morphology, the pathogen was identified as Alternaria alternata (Fr:Fr.) Keissler (2,3). The internal transcribed spacer (ITS) region of rDNA was amplified using the primers ITS1/ITS4 and the ITS sequence was 99% identical to A. alternata (GenBank Accession No. FJ228163). Pathogenicity tests were performed on detached, asymptomatic fruit. Six fruit were inoculated by placing a PDA plug containing mycelia on the upper surface of the fruit. Another six fruit received sterile PDA plugs. Fruit were cultured in petri dishes with a 12-h photoperiod at 25°C and 90% relative humidity. Black spot symptoms were observed on inoculated fruit but not control fruit after 5 days. The pathogen was reisolated from inoculated fruit and confirmed to be A. alternata. The pathogenicity test was repeated once. A. alternata has a broad host range, but to our knowledge, this is the first report of A. alternata infecting cherries in China. References: (1) Z. D. Fang. Research Methods of Plant Disease, 124, 1998. (2) E. G. Simmons. Alternaria themes and variations. Mycotaxon 37: 79, 1990. (3) T. Y. Zhang et al. Fungi Notes-Genera Alternaria in China, 16:32, 2003.
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Wei KJ, Li HQ, Chen HD, Li EB, Liu ZH. [Research on enhancement of the extraction efficiency of C-band LED with 2D photonic crystals]. GUANG PU XUE YU GUANG PU FEN XI = GUANG PU 2012; 32:2341-2346. [PMID: 23240392] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
On-chip light source is the main development part of the optoelectronic systems in the future. As on-chip light source, the main disadvantage of LED is its low extraction efficiency. Photonic crystal is an efficient method to increase the extraction efficiency of LED. The structure and parameters of the C-band LED was designed and the band gap of the 2D photonic crystals for different arrangement and different ratio was calculated using the finite-difference time-domain (FDTD) method, and then the best structural parameters of the 2D photonic crystals were determined using the method of band gap theory in this paper. Results show that the best structure is air holes PC with a triangular arrangement having a lattice constant of 500 nm and a ratio of 0.44.
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Liu ZH, Chen LL, Deng XL, Song HJ, Liao YF, Zeng TS, Zheng J, Li HQ. Methylation status of CpG sites in the MCP-1 promoter is correlated to serum MCP-1 in Type 2 diabetes. J Endocrinol Invest 2012; 35:585-9. [PMID: 21975431 DOI: 10.3275/7981] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
AIM Monocyte chemoattractant protein-1 (MCP-1) is a potent chemokine and plays an important role in atherosclerosis of Type 2 diabetes. The aim of this study was to investigate the methylation status of CpG sites in the MCP-1 promoter in Type 2 diabetic patients and its correlation to serum MCP- 1 level, and blood glucose level. METHODS The 32 patients with Type 2 diabetes and 15 healthy controls were enrolled into the study. Bodymass index, blood pressure, blood lipid, blood glucose, glycosylated hemoglobin (HbA1c), and serum MCP-1 were measured. Genomic DNA was isolated fromthe peripheral blood mononuclear cells (PBMC). Methylation status of CpG sites in theMCP-1 promoter was determined using methylation specific polymerase chain reaction. RESULTS The promoter region (2890-3050 bp) was predominantly methylated in PBMC from controls.Methylation of CpGmotifs were less methylated in the patients than in the controls (25% vs 80%; p<0.001), while the level of MCP-1 in serum was higher in patients with Type 2 diabetes (193.95±74.96 vs 88.46±55.10; p<0.001). MCP-1 promoter methylation was significantly correlated to serum MCP-1, HbA1c, fasting blood glucose, and triglyceride. CONCLUSION These data suggest that hypomethylation of CpG sites in the MCP-1 promoter region may be affected by blood glucose and TG, which then increase the serum MCP-1 level and may play a role in the vascular complications of Type 2 diabetes.
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Liu ZH, Zhong S, Stasko AK, Edwards MC, Friesen TL. Virulence profile and genetic structure of a North Dakota population of Pyrenophora teres f. teres, the causal agent of net form net blotch of barley. PHYTOPATHOLOGY 2012; 102:539-46. [PMID: 22494251 DOI: 10.1094/phyto-09-11-0243] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
A Pyrenophora teres f. teres population in North Dakota was analyzed for virulence variation and genetic diversity using 75 monospore isolates that were collected across a 4-year period (2004 to 2007) from two North Dakota State University agricultural experiment stations at Fargo and Langdon. Pathogenicity tests by inoculation onto 22 barley differential lines at seedling stage revealed 49 pathotypes, indicating a wide range of pathogenic diversity. Two-way analysis of variance of disease ratings revealed a significant difference in the virulence among isolates and in the resistance among barley lines, as well as in the interactions between the two. 'CI5791', 'Algerian', and 'Heartland' were three barley lines showing a high level of seedling resistance to all North Dakota isolates tested; however, many previously reported resistance genes have been overcome. Forty multilocus genotypes were identified from this set of isolates by genotyping at 13 simple-sequence repeat loci. High percentages of clonal cultures were detected in the samplings from 2005 and 2007 in Fargo and 2005 in Langdon. Using a clone-corrected sample set, the mean gene diversity (h) was estimated to be 0.58, approximately the same for both locations. The calculated Wright's F(ST) value is small (0.11) but was significantly >0, indicating a significant differentiation between the Fargo and Langdon populations. In the gametic disequilibrium test, only 3 of 78 possible pairwise comparisons over all isolates showed significant (P < 0.05) nonrandom association, suggesting a random mating mode. Our results suggest that the populations from the two locations are derived from a common source and undergo frequent recombination. This research provides important information for barley breeders regarding development and deployment of cultivars with resistance to net form net blotch in this region.
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Crook AD, Friesen TL, Liu ZH, Ojiambo PS, Cowger C. Novel necrotrophic effectors from Stagonospora nodorum and corresponding host sensitivities in winter wheat germplasm in the southeastern United States. PHYTOPATHOLOGY 2012; 102:498-505. [PMID: 22494247 DOI: 10.1094/phyto-08-11-0238] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
Stagonospora nodorum blotch (SNB), caused by the necrotrophic fungus Stagonospora nodorum (teleomorph: Phaeosphaeria nodorum), is among the most common diseases of winter wheat in the United States. New opportunities in resistance breeding have arisen from the recent discovery of several necrotrophic effectors (NEs, also known as host-selective toxins) produced by S. nodorum, along with their corresponding host sensitivity (Snn) genes. Thirty-nine isolates of S. nodorum collected from wheat debris or grain from seven states in the southeastern United States were used to investigate the production of NEs in the region. Twenty-nine cultivars with varying levels of resistance to SNB, representing 10 eastern-U.S. breeding programs, were infiltrated with culture filtrates from the S. nodorum isolates in a randomized complete block design. Three single-NE Pichia pastoris controls, two S. nodorum isolate controls, and six Snn-differential wheat controls were also used. Cultivar-isolate interactions were visually evaluated for sensitivity at 7 days after infiltration. Production of NEs was detected in isolates originating in each sampled state except Maryland. Of the 39 isolates, 17 produced NEs different from those previously characterized in the upper Great Plains region. These novel NEs likely correspond to unidentified Snn genes in Southeastern wheat cultivars, because NEs are thought to arise under selection pressure from genes for resistance to biotrophic pathogens of wheat cultivars that differ by geographic region. Only 3, 0, and 23% of the 39 isolates produced SnToxA, SnTox1, and SnTox3, respectively, by the culture-filtrate test. A Southern dot-blot test showed that 15, 74, and 39% of the isolates carried the genes for those NEs, respectively; those percentages were lower than those found previously in larger international samples. Only two cultivars appeared to contain known Snn genes, although half of the cultivars displayed sensitivity to culture filtrates containing unknown NEs. Effector sensitivity was more frequent in SNB-susceptible cultivars than in moderately resistant (MR) cultivars (P = 0.008), although some susceptible cultivars did not exhibit sensitivity to NEs produced by isolates in this study and some MR cultivars were sensitive to NEs of multiple isolates. Our results suggest that NE sensitivities influence but may not be the only determinant of cultivar resistance to S. nodorum. Specific knowledge of NE and Snn gene frequencies in this region can be used by wheat breeding programs to improve SNB resistance.
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Xu Y, Ding XQ, Zou JZ, Liu ZH, Jiang SH, Chen YM. Serum hepcidin in haemodialysis patients: associations with iron status and microinflammation. J Int Med Res 2012; 39:1961-7. [PMID: 22118000 DOI: 10.1177/147323001103900542] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
Hepcidin plays a key role in iron homeostasis. This cross-sectional study measured the serum hepcidin levels of 48 maintenance haemodialysis patients and 20 age-matched healthy control subjects using a competitive enzyme-linked immunosorbent assay (C-ELISA). Serum hepcidin, interleukin (IL)-6 and high-sensitivity C-reactive protein levels were significantly higher in maintenance haemodialysis patients compared with control subjects. In all patients, there was a positive correlation between serum hepcidin levels and ferritin, transferrin saturation and IL-6, and an inverse correlation between serum hepcidin and unsaturated iron-binding capacity, total iron-binding capacity (TIBC) and transferrin. Linear regression analyses showed that ferritin and TIBC were independently associated with serum hepcidin levels. In conclusion, serum hepcidin levels are associated with iron status and microinflammation (defined as hsCRP < 15 mg/l, without clinical manifestation of inflammation) in maintenance haemodialysis patients. The C-ELISA method for measuring serum hepcidin should facilitate the routine measurement of hepcidin in clinical practice.
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Zheng JM, Yao GH, Cheng Z, Wang R, Liu ZH. Pathogenic role of mast cells in the development of diabetic nephropathy: a study of patients at different stages of the disease. Diabetologia 2012; 55:801-11. [PMID: 22130579 DOI: 10.1007/s00125-011-2391-2] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/03/2011] [Accepted: 11/04/2011] [Indexed: 12/16/2022]
Abstract
AIMS/HYPOTHESIS Increased renal mast cells have been detected in diabetic nephropathy. However, only a few patients have been examined. Evidence of the involvement of mast cells in diabetic nephropathy is still scarce, and no observation of mast cells during the development of diabetic nephropathy has yet been reported in humans. Here, we examined changes in renal mast cells in patients at different stages of diabetic nephropathy and related these to the development of the disease. METHODS Eighty patients at different clinical stages of diabetic nephropathy and 16 normal kidney donors were recruited. Immunohistochemical staining for tryptase, chymase, TGF-β1, renin and TNF-α was done on renal sections from patients and control participants. Changes in mast cell number, degranulation, subtype and phenotype were examined. Correlation between mast cells and patients' clinical and pathological indices was analysed. RESULTS With progression of diabetic nephropathy, the number and degranulation level of mast cells increased. Increase in mast cell number and degranulation level correlated significantly with tubular interstitial injury. Almost all renal mast cells in patients with diabetic nephropathy were found to produce chymase, renin, TGF-β1 and TNF-α. The level of TNF-α in mast cells increased with progression of diabetic nephropathy. CONCLUSIONS/INTERPRETATION This study suggests that mast cells are involved in development of diabetic nephropathy. Through release of bioactive substances, such as tryptase, chymase, TGF-β1, renin and TNF-α, into the tubular interstitium by degranulation, mast cells could promote renal inflammation and fibrosis, and thus contribute to diabetic nephropathy.
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Zheng DD, Liu ZH, Fang J, Wang XY, Zhang J. The effect of age and cerebral ischemia on diffusion-weighted proton MR spectroscopy of the human brain. AJNR Am J Neuroradiol 2012; 33:563-8. [PMID: 22081680 PMCID: PMC7966455 DOI: 10.3174/ajnr.a2793] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2011] [Accepted: 06/16/2011] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE DW-MRS is a promising tool for the noninvasive identification of the cellular response to cerebral ischemia. To date, the potential confounding effects of aging and the stage of ischemia are unknown. We, therefore, examined the cross-sectional effects of age and different stages of cerebral ischemia on the diffusion of brain metabolites. MATERIALS AND METHODS The ADCs of 3 major metabolites, including Cho, Cr, and NAA were measured by DW-MRS in healthy younger (n = 26, 24 ± 2.2 years of age) and older (n = 17, 63 ± 7.0 years of age) adults, as well as in patients with acute (n = 7, 57 ± 4.0 years of age) and subacute (n = 12, 62 ± 7.8 years of age) cerebral ischemia. RESULTS Compared with younger adults, healthy older adults presented with significantly reduced ADC values of NAA (P = .000052), Cr (P = .000018), and Cho (P = .00075). Meanwhile, the ADC values of NAA (F(2,36) = 6.057, P = .006), Cr (F(2,36) = 5.634, P = .008), and Cho (F(2,36) = 8.167, P = .001) were significantly different among the acute cerebral ischemia group, subacute cerebral ischemia group, and healthy older controls. These metabolites decreased in the acute stage of cerebral ischemia but increased in the subacute stage, compared with age-matched controls. CONCLUSIONS The effect of age should be considered when analyzing diffusion of cerebral metabolites with DW-MRS. Our observations also suggest that metabolite diffusion data may be used to reveal changes in the intracellular environment, depending on the pathologic status of ischemia.
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Yin Z, Kong QR, Zhao ZP, Wu ML, Mu YS, Hu K, Liu ZH. Position effect variegation and epigenetic modification of a transgene in a pig model. GENETICS AND MOLECULAR RESEARCH 2012; 11:355-69. [PMID: 22370938 DOI: 10.4238/2012.february.16.1] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Sequences proximal to transgene integration sites are able to regulate transgene expression, resulting in complex position effect variegation. Position effect variegation can cause differences in epigenetic modifications, such as DNA methylation and histone acetylation. However, it is not known which factor, position effect or epigenetic modification, plays a more important role in the regulation of transgene expression. We analyzed transgene expression patterns and epigenetic modifications of transgenic pigs expressing green fluorescent protein, driven by the cytomegalovirus (CMV) promoter. DNA hypermethylation and loss of acetylation of specific histone H3 and H4 lysines, except H4K16 acetylation in the CMV promoter, were consistent with a low level of transgene expression. Moreover, the degree of DNA methylation and histone H3/H4 acetylation in the promoter region depended on the integration site; consequently, position effect variegation caused variations in epigenetic modifications. The transgenic pig fibroblast cell lines were treated with DNA methyltransferase inhibitor 5-Aza-2'-deoxycytidine and/or histone deacetylase inhibitor trichostatin A. Transgene expression was promoted by reversing the DNA hypermethylation and histone hypoacetylation status. The differences in DNA methylation and histone acetylation in the CMV promoter region in these cell lines were not significant; however, significant differences in transgene expression were detected, demonstrating that variegation of transgene expression is affected by the integration site. We conclude that in this pig model, position effect variegation affects transgene expression.
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Hao GY, Goldstein G, Sack L, Holbrook NM, Liu ZH, Wang AY, Harrison RD, Su ZH, Cao KF. Ecology of hemiepiphytism in fig species is based on evolutionary correlation of hydraulics and carbon economy. Ecology 2012; 92:2117-30. [PMID: 22164836 DOI: 10.1890/11-0269.1] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Woody hemiepiphytic species (Hs) are important components of tropical rain forests, and they have been hypothesized to differ from non-hemiepiphytic tree species (NHs) in adaptations relating to water relations and carbon economy; but few studies have been conducted comparing ecophysiological traits between the two growth forms especially in an evolutionary context. Using common-garden plants of the genus Ficus, functional traits related to plant hydraulics and carbon economy were compared for seven NHs and seven Hs in their adult terrestrial "tree-like" growth phase. We used phylogenetically independent contrasts to test the hypothesis that differences in water availability selected for contrasting suites of traits in Hs and NHs, driving evolutionary correlations among functional traits including hydraulic conductivity and photosynthetic traits. Species of the two growth forms differed in functional traits; Hs had substantially lower xylem hydraulic conductivity and stomatal conductance, and higher instantaneous photosynthetic water use efficiency. Leaf morphological and structural traits also differed strikingly between the two growth forms. The Hs had significantly smaller leaves, higher leaf mass per area (LMA), and smaller xylem vessel lumen diameters. Across all the species, hydraulic conductivity was positively correlated with leaf gas exchange indicating high degrees of hydraulic-photosynthetic coordination. More importantly, these correlations were supported by correlations implemented on phylogenetic independent contrasts, suggesting that most trait correlations arose through repeated convergent evolution rather than as a result of chance events in the deep nodes of the lineage. Vatiation in xylem hydraulic conductivity was also centrally associated with a suite of other functional traits related to carbon economy and growth, such as LMA, water use efficiency, leaf nutrient concentration, and photosynthetic nutrient use efficiency, indicating important physiological constraints or trade-offs among functional traits. Shifts in this trait cluster apparently related to the adaptation to drought-prone canopy growth during the early life cycle of Hs and clearly affected ecophysiology of the later terrestrial stage of these species. Evolutionary flexibility in hydraulics and associated traits might be one basis for the hyper-diversification of Ficus species in tropical rain forests.
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Luk NMT, Hui M, Lee HCS, Fu LH, Liu ZH, Lam LY, Eastel M, Chan YKA, Tang LSN, Cheng TS, Siu FYC, Ng SC, Lai YKD, Ho KM. Antibiotic-resistant Propionibacterium acnes among acne patients in a regional skin centre in Hong Kong. J Eur Acad Dermatol Venereol 2011; 27:31-6. [PMID: 22103749 DOI: 10.1111/j.1468-3083.2011.04351.x] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
BACKGROUND There has been no study on antibiotic-resistant Propionibacterium acnes in Hong Kong. OBJECTIVE We investigated the prevalence and pattern of antibiotic-resistant P. acnes and to identify any associated factors for harbouring the resistant strains. METHODS Culture and sensitivity testing of P. acnes to commonly used antibiotics were performed. Resistance to tetracycline was defined at a minimal inhibitory concentration (MIC) of 2 μg/mL or more; erythromycin at an MIC of 0.5 μg/mL or more; clindamycin at an MIC of 0.25 μg/mL or more according to EUCAST. For breakpoints of doxycycline and minocycline, those with an MIC of 1 μg/mL or more were defined as resistant strains. RESULTS Among the 111 specimens collected from 111 patients, 86 strains of P. acnes were recovered, one from each specimen. Twenty-five specimens had no growth. Forty-seven (54.8%) strains were found to be resistant to one or more antibiotics. Forty-six (53.5%), 18 (20.9%), 14 (16.3%), 14(16.3%) and 14 (16.3%) strains were resistant to clindamycin (CL), erythromycin (EM), tetracycline (TET), doxycycline (DOX) and minocycline (MR) respectively. Ten strains (11.6%) had cross resistance between the MLS antibiotics (erythromycin or clindamycin), one strain (1.2%) had cross resistance among the cyclines and 14 strains (16.4%) had cross resistance between the MLS and cycline antibiotics. Binary logistic regression showed an association between MLS antibiotic resistance with an increased age whereas cycline resistance was associated with the duration of treatment. CONCLUSION Antibiotic-resistant P. acnes is prevalent in Hong Kong. Dermatologists should be more vigilant in prescribing antibiotics for acne patients.
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Huang BF, Sun YL, Wu FR, Liu ZH, Wang ZJ, Luo LF, Zhang YG, Wang DS. Isolation, sequence analysis, and characterization of androgen receptor in Southern catfish, Silurus meridionalis. FISH PHYSIOLOGY AND BIOCHEMISTRY 2011; 37:593-601. [PMID: 21188633 DOI: 10.1007/s10695-010-9461-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2010] [Accepted: 12/08/2010] [Indexed: 05/30/2023]
Abstract
Androgen receptor (AR), the mediator of androgen, plays important roles in the androgen signal pathway. In the present study, we isolated and analyzed the cDNA sequence and tissue distribution of androgen receptor in Southern catfish (scAR). The full-length cDNA of scAR contains 3,116 bp with an open reading frame (ORF) of 2,415 bp, encoding a protein of 804 amino acids (aa). Tissue distribution analysis of scAR revealed that it was expressed in all tissues examined, with no sexual dimorphism in the ovary and testis. Phylogenetic analysis and multiple amino acids sequence alignment indicated the close relationship and high similarity of scAR with ARs from cypriniform species. In addition, partial sequences of ARs from 7 other siluriform species were also isolated. Comparison of catfish ARs with those from other vertebrates revealed that an extra C-terminal tail of about 20aa exists in all the ARs from siluriform fishes investigated, but not in other ARs. The extra sequence was resulted from a 4-bp insertion before the stop codon of other vertebrate ARs, and it was identical in ARs from siluriform species of the same genus but different among ARs from species of different genera. We report here for the first time that the ARs from siluriform species are longer in C-terminal than those from other vertebrates and it might be useful in reconstruction of the phylogenetic relationship among siluriform fishes. The significance of the extra C-terminal tail for AR function remains elusive.
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Kong QR, Wu ML, Zhang L, Wang F, Yin Z, Mu YS, Liu ZH. Transgene insertion affects transcription and epigenetic modification of flanking host sequence in transgenic pigs. Cell Mol Biol (Noisy-le-grand) 2011; 57 Suppl:OL1505-OL1512. [PMID: 21699765] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2011] [Accepted: 06/09/2011] [Indexed: 05/31/2023]
Abstract
Transgenic technology has been used for years to study gene function, produce important proteins, and generate models for the study of human diseases. However, the efficiency of producing transgenic animal lines that retain normal function is extremely low. The low efficiency can be mainly attributed to the integrated transgene. A further understanding of the effects of transgene integration on transcription and epigenetic modification of the host genome would improve the transgenic efficiency. Therefore, we utilized three transgenic pigs produced by SCNT expressing GFP, to identify alterations of transcription, DNA methylation and histone acetylation resulting from integration of the GFP gene. Multiple copies of the transgene integrated into a single site of the three transgenic pigs were verified by TAIL—PCR and the integration sites were different in each pig. We observed that the integrated transgene frequently resulted in significantly low transcription of flanking sequences in various tissues of transgenic pigs in comparison with wild—type pigs. Corresponding with the low transcription, DNA hypermethylation and loss of acetylation of histone H3 and H4 were detected. Our results demonstrate that the abnormal transcription and epigenetic modification of sequences flanking the transgene were not correlated with the expression of the transgene. However, the disturbance caused by the insertion of the transgene, was dependent upon the integration site. This suggests that some sequences in the host genome could permit integration and expression of transgene without causing defects in the host.
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169
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Hao GY, Wang AY, Liu ZH, Franco AC, Goldstein G, Cao KF. Differentiation in light energy dissipation between hemiepiphytic and non-hemiepiphytic Ficus species with contrasting xylem hydraulic conductivity. TREE PHYSIOLOGY 2011; 31:626-636. [PMID: 21697148 DOI: 10.1093/treephys/tpr035] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Hemiepiphytic Ficus species (Hs) possess traits of more conservative water use compared with non-hemiepiphytic Ficus species (NHs) even during their terrestrial growth phase, which may result in significant differences in photosynthetic light use between these two growth forms. Stem hydraulic conductivity, leaf gas exchange and chlorophyll fluorescence were compared in adult trees of five Hs and five NHs grown in a common garden. Hs had significantly lower stem hydraulic conductivity, lower stomatal conductance and higher water use efficiency than NHs. Photorespiration played an important role in avoiding photoinhibition at high irradiance in both Hs and NHs. Under saturating irradiance levels, Hs tended to dissipate a higher proportion of excessive light energy through thermal processes than NHs, while NHs dissipated a larger proportion of electron flow than Hs through the alternative electron sinks. No significant difference in maximum net CO2 assimilation rate was found between Hs and NHs. Stem xylem hydraulic conductivity was positively correlated with maximum electron transport rate and negatively correlated with the quantum yield of non-photochemical quenching across the 10 studied Ficus species. These findings indicate that a canopy growth habit during early life stages in Hs of Ficus resulted in substantial adaptive differences from congeneric NHs not only in water relations but also in photosynthetic light use and carbon economy. The evolution of epiphytic growth habit, even for only part of their life cycle, involved profound changes in a suite of inter-correlated ecophysiological traits that persist to a large extent even during the later terrestrial growth phase.
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Kuang YL, Yuan WJ, Zhang Z, Xing TH, Yu Q, Liu J, Chen L, Liu ZH, Peng ZH. [Effects of non-bioartificial liver support system on Gc-globulin in patients with liver failure]. ZHONGHUA GAN ZANG BING ZA ZHI = ZHONGHUA GANZANGBING ZAZHI = CHINESE JOURNAL OF HEPATOLOGY 2011; 19:196-200. [PMID: 21586238 DOI: 10.3760/cma.j.issn.1007-3418.2011.03.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
OBJECTIVE To investigate the effects of artificial liver support system(plasma exchange combined with continuous veno - venous hemodiafiltration, PE + CVVHDF) on Gc globulin in patients with liver failure. METHODS 81 patients with liver failure were divided into 4 groups according to the treatment protocols and indicators such as liver function and clinical symptoms. Totally 29 effective cases and 14 ineffective cases in the ALSS group versus 15 effective cases and 23 ineffective cases in the medical group were included. Finally the changes of Gc globulin were observed in four subgroups before and after treatment. The correlation between Gc globulin and IL-10, IL-4, IL-18, TNFa, endotoxin, NO, sVCAM-1and sICAM-1were analyzed by Pearson correlation analysis. RESULTS The effectiveness rate was 67.44% in ALSS group and 34.21% in the medical treatment (P less than 0.01). Gc globulin, one of liver cell protection proteins was notably increased following the artificial liver treatment as compared with the increase in the medical treatment (P less than 0.01). The time-response curve of Gc globulin level had a significant upward trend in the effective group as compared to no significant rise in the ineffective group. Moreover, the Gc globulin was negatively correlated with IL-4, IL-18, TNFa, SVCAM-1, SICAM-1 and NO. In contrast, no correlation existed between Gc globulin and IL-10. The treatment with artificial liver can improve the outcome of the patients with liver failure. The level of Gc globulin was correlated with the curative effect and thus may be used as a potential indicator for curative effect forcast in the patients with liver failure.
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Wang X, Zang JJ, Wang H, Nie H, Wang TC, Deng XY, Gu YQ, Liu ZH, Jia G. Pulmonary toxicity in mice exposed to low and medium doses of water-soluble multi-walled carbon nanotubes. JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY 2010; 10:8516-8526. [PMID: 21121361 DOI: 10.1166/jnn.2010.2688] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Carbon nanotubes (CNTs) are a class of new allotrope of carbon. Different functionalized CNTs may vary from their physical and chemical properties to the biological property. In this study, the toxicity of water-soluble taurine multi-walled CNTs (tau-MWNTs), raw MWNTs and positive control crystalline silicon dioxide particles on mouse lungs via intratracheal instillation (i.t.) was investigated. The dosages we used were 0.125, 0.25, 0.5 or 1 mg/kg of tau-MWNTs and raw MWNTs, and 1 mg/kg of silicon dioxide particles; Serum and lungs were collected at 1, 7, 14 or 28 days postexposure. The biochemical and cellular parameters were assessed, which include the ratio of the lung weight and body weight (lung indices), lactate dehydrogenase (LDH), alkaline phosphatase (ALP) and angiotensin converting enzyme (ACE) in serum, and malondialdehyde (MDA), reduced glutathione (GSH), total sulfhydryl group (TSH) in lung tissue homogenates as well as the hydroxyproline in lungs. The characteristic recovery of the lung injury at 28 days postexposure was examined by the assessment of LDH, ALP, lung indices, and histopathology. ACE, MDA, GSH, TSH and histopathological changes showed that tau-MWNTs were less toxic than the raw MWNTs. Histopathological and ultrastructural investigation indicated that the acute pulmonary inflammation in lungs alleviated after 7d postexposure, and were greatly recovered within 28d. Meanwhile, the entrapment of tau-MWNTs reduced greatly by the 28d postexposure. Whereas the heavier pathologic changes induced by raw MWNTs lasted 7 days more than that of tau-MWNTs. Notably, no occurrence of granulomas and fibrosis were found in this study both in the two CNTs samples through 28d postexposure. Silicon dioxide particles, on the contrary, produced more severe damage to lungs than CNTs did in lung index, as well as other biochemical and cellular parameters. These findings indicate that water-soluble tau-MWNTs in low and medium doses induce slight and recoverable pulmonary inflammation in mice, and are less toxic than the insoluble raw MWNTs.
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172
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Hu WX, Liu ZZ, Chen HP, Zhang HT, Li LS, Liu ZH. Clinical characteristics and prognosis of diffuse proliferative lupus nephritis with thrombotic microangiopathy. Lupus 2010; 19:1591-8. [PMID: 20798137 DOI: 10.1177/0961203310376523] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
We retrospectively analyzed the clinicopathologic characteristics and prognosis of 33 patients with diffuse proliferative lupus nephritis (class IV LN) complicated with thrombotic microangiopathy (TMA). Eighty-one percent of patients had renal dysfunction (mean Scr 3.1 ± 2.0 mg/dl), among whom 42.4% needed acute hemodialysis. Nephrotic proteinuria, gross hematuria and hypertension were presented in 57.6%, 24.2% and 93.9% of the patients. Microangiopathic hemolytic anemia, serum anti-dsDNA and anticardiolipin antibodies were found in 60.6%, 75.8% and 33.3% of the patients. Renal biopsy showed IV-G in 75.8%, class IV with class V in 21.2%, and IV-S in 1.23% of the patients. Glomerular segmental necrosis, microthrombi, crescents and arteriolar thrombosis were found in 51.5%, 69.7%, 60.6% and 60.7% of the patients, respectively. The follow up was 1 to 101 months (median 13 months). Only 50% of patients showed response to treatment. Three patients died, 10 developed end-stage renal failure (ESRF). The 5-year patient and renal survival rate was 69.2% and 46.7%, respectively. Major risks for ESRF included: a need for acute dialysis on admission, no response to the treatment and high renal chronic index. The results showed that class IV lupus nephritis with TMA has high mortality and low renal survival.
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Liu ZH, Zhang YG, Wang DS. Studies on feminization, sex determination, and differentiation of the Southern catfish, Silurus meridionalis--a review. FISH PHYSIOLOGY AND BIOCHEMISTRY 2010; 36:223-235. [PMID: 19002765 DOI: 10.1007/s10695-008-9281-7] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/02/2008] [Accepted: 10/13/2008] [Indexed: 05/27/2023]
Abstract
The sex ratio of the feral Southern catfish was reported to be about 1:1, while the fish obtained by artificial fertilization were always female. Hence, we examined the possible influence of the micro-environment during artificial insemination (pH of the ovarian fluid and concentration of the semen) and early development (feed, hatching temperature, and water) on the sex ratio of Southern catfish fry. In order to examine the possibility of the occurrence of gynogenesis during artificial propagation, cytological observations on the insemination processes and the artificial induction of gynogenesis were also performed. However, no male fish were obtained even in these experiments, excluding the possibilities of these micro-environmental changes on catfish sex ratio and the occurrence of gynogenesis during artificial propagation. Female-to-male sex reversal was achieved by treatment with fadrozole (an aromatase inhibitor) and tamoxifen (an estrogen receptor antagonist). Histological analyses on the gonadal development of both female and induced male fish were subsequently performed. Moreover, several genes involved in sex differentiation, such as dmrt1, foxl2, and cyp19, and three subunits of gonadotropin (gth), i.e., gthalpha, lhbeta, and fshbeta, were isolated. Their expression patterns were studied under normal gonadal development and sex reversal conditions. The results revealed that dmrt1, foxl2, and cyp19a were closely related to catfish sex differentiation, and the gth subunits were possibly related to ovarian differentiation and oocyte development. Taken together, we hypothesized that estrogen was highly responsible for the ovarian differentiation and feminization of catfish fry under artificial propagation, although the mechanism involved remains elusive.
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Fang SF, Pei H, Liu ZH. [Spectral characters analysis of ground objects in snowmelt period in the northern slope of Tianshan Mountains]. GUANG PU XUE YU GUANG PU FEN XI = GUANG PU 2010; 30:1301-1304. [PMID: 20672622] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Urumqi River Basin and Juntanghu Basin, located in the northern slope of Tianshan Mountains in Xinjiang, were selected as typical study areas. With the portable field spectrometer CI700 produced by CID in the United States and from a large number of field investigations and field measurements in the snowmelt period (usually starts in the end of February or the beginning of March, and goes on for many days) from 2006 to 2009, a variety of spectral curves and their variation of typical ground objects in the snowmelt period in the northern slope of Tianshan Mountains, such as snow, ice, water and soil, were obtained, and spectral characters analysis was carried out based on the collected data. The results showed that the classes of ground objects in snowmelt period are quite monotone, however, a great challenge was brought about to the quantitative remote sensing research on surface parameters in snowmelt period because of the interactive effects of the complex systems of snow-ice-water-soil, the spectral properties of typical ground objects, and their complex changes. Reflectance of soil with different moisture conditions is distinct, as well as reflectance of ice and snow under different environment or dissimilar mixtures have obvious development trends. The series of observations and analysis of the typical and complex spectral features in snowmelt period are of great significance for the fundamental study of objects' spectral characteristics, as well as for the application of quantitative remote sensing studies.
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Xiao WJ, Gong YX, Liu ZH, Wang JM. Single nucleotide polymorphisms and haplotypes of TLR6 gene in Chinese Cantonese population. Int J Immunogenet 2010; 37:245-51. [PMID: 20402822 DOI: 10.1111/j.1744-313x.2010.00916.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Sequence polymorphisms in the coding region of Toll-like receptor 6 gene were investigated in Chinese Cantonese population. By amplifying and sequencing a 2787 bp segment containing the entire coding region of TLR6 gene of 191 individuals in Chinese Cantonese population, a total of seven single nucleotide polymorphisms (SNP) along with their frequencies were detected. Comparing these data with SNP published in dbSNP database of National Center for Biotechnology Information (NCBI), two SNP (+176T/C and +1408G/T) were firstly reported, and five SNP caused amino-acid substitution. Sixteen haplotypes and their distributions were reconstructed. Linkage disequilibrium analysis and neutrality test were also performed. Comparing with other ethnic populations, Chinese Cantonese displayed obvious differences in TLR6 polymorphism. It may in part reflect the ethnic diversity of pathogen susceptibility and facilitate to develop the disease-association studies as well as population genetics and evolutionary research.
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