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181.
Yau-Hung Chen Yun-Hsin Wang Tsung-Han Yu Hsin-Ju Wu Chiung-Wen Pai 《Transgenic research》2009,18(6):855-864
We generated a transgenic line Tg(k18:shh:RFP) with overexpression of Sonic hedgehog in the skin epidermis. By 5 day-post-fertilization (dpf), many epidermal lesions were
clearly observed, including a swollen yolk sac, epidermis growth malformation around the eyes and at the basement of the pectoral
fins. Skin histology revealed embryos derived from Tg(k18:shh:RFP) displayed an elevated Nuclear/Cytoplasmic ratio and pleomorphic nuclei compared to their wild type littermates, suggesting
the abnormal growth pattern on the epidermis of Tg(k18:shh:RFP) embryos were dysplasia. Later (by 7 dpf), Tg(k18:shh:RFP) embryos displayed broader pectoral fins which are similar to the polydactyly phenotypes of Nevoid basal cell carcinoma syndrome
(NBCCS)/Gorlin patients and polydactylous mice. In addition, treatment with cyclopamine is able to enhance and prolong the
survival rates and survival durations of Tg(k18:shh:RFP) embryos. In conclusion, this unique Tg(k18:shh:RFP) fish line, should be an excellent experimental animal for screening for a lower toxicity level of the new Hh-inhibitor and
can even be used as a new anti-cancer drug-screening platform. 相似文献
182.
Identification and characterization of zinc-starvation-induced ZIP transporters from barley roots 总被引:3,自引:0,他引:3
Zinc (Zn) is an essential element for plants but limited information is currently available on the molecular basis for Zn2+ transport in crop species. To expand the knowledge on Zn2+ transport in barley (Hordeum vulgare L.), a cDNA library prepared from barley roots was expressed in the yeast (Saccharomyces cerevisiae) mutant strain Δzrt1/Δzrt2, defective in Zn2+ uptake. This strategy resulted in isolation and identification of three new Zn2+ transporters from barley. All of the predicted proteins have a high similarity to the ZIP protein family, and are designated HvZIP3, HvZIP5 and HvZIP8, respectively. Complementation studies in Δzrt1/Δzrt2 showed restored growth of the yeast cells transformed with the different HvZIPs, although with different efficiency. Transformation into Fe2+ and Mn2+ uptake defective yeast mutants showed that the HvZIPs were unable to restore the growth on Fe2+ and Mn2+ limited media, respectively, indicating a specific role in Zn2+ transport. In intact barley roots, HvZIP8 was constitutively expressed whereas HvZIP3 and HvZIP5 were mainly expressed in ?Zn plants. These results suggest that HvZIP3, HvZIP5 and HvZIP8 are Zn2+ transporters involved in Zn2+ homeostasis in barley roots. The new transporters may facilitate breeding of barley genotypes with improved Zn efficiency and Zn content. 相似文献
183.
Chen Chun Pai Ignacio García Shao Win Wang Sue Cotterill Stuart A. MacNeill Stephen E. Kearsey 《Molecular biology of the cell》2009,20(4):1213-1222
The tetrameric GINS complex, consisting of Sld5-Psf1-Psf2-Psf3, plays an essential role in the initiation and elongation steps of eukaryotic DNA replication, although its biochemical function is unclear. Here we investigate the function of GINS in fission yeast, using fusion of Psf1 and Psf2 subunits to a steroid hormone-binding domain (HBD) to make GINS function conditional on the presence of β-estradiol. We show that inactivation of Psf1-HBD causes a tight but rapidly reversible DNA replication arrest phenotype. Inactivation of Psf2-HBD similarly blocks premeiotic DNA replication and leads to loss of nuclear localization of another GINS subunit, Psf3. Inactivation of GINS has distinct effects on the replication origin association and chromatin binding of two of the replicative DNA polymerases. Inactivation of Psf1 leads to loss of chromatin binding of DNA polymerase ε, and Cdc45 is similarly affected. In contrast, chromatin association of the catalytic subunit of DNA polymerase α is not affected by defective GINS function. We suggest that GINS functions in a pathway that involves Cdc45 and is necessary for DNA polymerase ε chromatin binding, but that a separate pathway sets up the chromatin association of DNA polymerase α. 相似文献
184.
Mobile Macromolecules in Plant Development 总被引:1,自引:0,他引:1
Plant cells transmit developmental signals and distribute nutrients via dynamic intercellular channels termed plasmodesmata
(PD). Multidisciplinary inquiries have provided evidence that plasmodesmatal regulation is critical to fundamental plant functions,
such as development, host–pathogen interactions, and systemic RNA silencing. This review focuses on macromolecules that transport
cell-to-cell through PD and describes their implications on plant development. 相似文献
185.
Tzu-Yi Pai S. C. Wang C. F. Chiang H. C. Su L. F. Yu P. J. Sung C. Y. Lin H. C. Hu 《Bioprocess and biosystems engineering》2009,32(6):781-790
Three types of adaptive network-based fuzzy inference system (ANFIS) in which the online monitoring parameters served as the
input variable were employed to predict suspended solids (SSeff), chemical oxygen demand (CODeff), and pHeff in the effluent from a biological wastewater treatment plant in industrial park. Artificial neural network (ANN) was also
used for comparison. The results indicated that ANFIS statistically outperforms ANN in terms of effluent prediction. When
predicting, the minimum mean absolute percentage errors of 2.90, 2.54 and 0.36% for SSeff, CODeff and pHeff could be achieved using ANFIS. The maximum values of correlation coefficient for SSeff, CODeff, and pHeff were 0.97, 0.95, and 0.98, respectively. The minimum mean square errors of 0.21, 1.41 and 0.00, and the minimum root mean
square errors of 0.46, 1.19 and 0.04 for SSeff, CODeff, and pHeff could also be achieved. 相似文献
186.
普通烟草K^+通道基因NKT4的克隆、序列和表达分析 总被引:2,自引:0,他引:2
通过比对拟南芥、胡萝卜、番茄和马铃薯的K+通道氨基酸序列得到了保守序列,设计1对简并引物,利用RT-PCR获得3条490bp的普通烟草K+通道基因中间片段.以其中一条中间片段设计特异性引物,应用RACE方法得到5′末端和3′末端cDNA序列.通过拼接并结合全长克隆及测序验证,获得一个未报道的普通烟草K+通道基因,并将其命名为NKT4(GenBank登录号为FJ233071).NKT4的cDNA全长为2937bp,其中5′非编码区45bp、编码区2679bp、3′非编码区213bp;编码区编码892个AA.构建了一个烟草、拟南芥及相关植物K+通道蛋白的系统进化树.基因表达分析表明,NKT4主要在烟草主根和侧根中表达,在烟草叶中也有少量表达. 相似文献
187.
Background
Variability in interferon-gamma release assays (IGRAs) results for tuberculosis has implications for interpretation of results close to the cut-point, and for defining thresholds for test conversion and reversion. However, little is known about the within-subject variability (reproducibility) of IGRAs. Several national guidelines recommend a two-step testing procedure (tuberculin skin test [TST] followed by IGRA) for the diagnosis of LTBI. However, the effect of a preceding TST on subsequent IGRA results has been reported in studies with apparently conflicting results.Methodology/Findings
We conducted a systematic review to synthesize evidence on within-subject variability of IGRA results and the potential boosting effect of TST. We searched several databases and reviewed citations of previous reviews on IGRAs. We included studies using commercial IGRAs, in addition to non-commercial versions of the ELISPOT assay. Four studies, fulfilling our predefined criteria, examined within-subject variability and 13 studies evaluated TST effects on subsequent IGRA responses. Meta-analysis was not considered appropriate because of heterogeneity in study methods, assays, and populations. Although based on limited data, within-subject variability was present in all studies but the magnitude varied (16-80%) across studies. A TST induced “boosting” of IGRA responses was demonstrated in several studies and although more pronounced in IGRA-positive (i.e. sensitized) individuals, also occurred in a smaller but not insignificant proportion of IGRA-negative subjects. The TST appeared to affect IGRA responses only after 3 days and may apparently persist for several months, but evidence for this is weak.Conclusions/Significance
Although reproducibility data are scarce, significant within person IGRA variability has been reported. If confirmed in more studies, this has implications for the interpretation of results close to the cut-point and for definition of conversions and reversions. Although the effect of TST on IGRA results is likely to be inconsequential in IGRA-positive subjects, in IGRA-negative subjects, the interpretation of results may be confounded by a preceding TST if administered more than 3 days prior to an IGRA. 相似文献188.
Peter Daley Joy Sarojini Michael Kalaiselvan S Asha Latha Dilip Mathai K. R. John Madhukar Pai 《PloS one》2009,4(5)
Background
Direct sputum smear microscopy for tuberculosis (TB) lacks sensitivity for the detection of acid fast bacilli. Sputum pretreatment procedures may enhance sensitivity. We did a pilot study to compare the diagnostic accuracy and incremental yield of two short-duration (<1 hour) sputum pretreatment procedures to optimize direct smears among patients with suspected TB at a referral hospital in India.Methodology/Findings
Blinded laboratory comparison of bleach and universal sediment processing (USP) pretreated centrifuged auramine smears to direct Ziehl-Neelsen (ZN) and direct auramine smears and to solid (Loweinstein-Jensen (LJ)) and liquid (BACTEC 460) culture. 178 pulmonary and extrapulmonary TB suspects were prospectively recruited during a one year period. Thirty six (20.2%) were positive by either solid or liquid culture. Direct ZN smear detected 22 of 36 cases and direct auramine smears detected 26 of 36 cases. Bleach and USP centrifugation detected 24 cases each, providing no incremental yield beyond direct smears. When compared to combined culture, pretreated smears were not more sensitive than direct smears (66.6% vs 61.1 (ZN) or 72.2 (auramine)), and were not more specific (92.3% vs 93.0 (ZN) or 97.2 (auramine).Conclusions/Significance
Short duration sputum pretreatment with bleach and USP centrifugation did not increase yield as compared to direct sputum smears. Further work is needed to confirm this in a larger study and also determine if longer duration pre-treatment might be effective in optimizing smear microscopy for TB. 相似文献189.
Nitika Pant Pai Milton Estes Erica E. M. Moodie Arthur L. Reingold Jacqueline P. Tulsky 《PloS one》2009,4(9)
Background
Jails are an important venue of HIV care and a place for identification, treatment and referral for care. HIV infected inmates in the San Francisco County jail are offered antiretroviral treatment (ART), which many take only while in jail. We evaluated the effect of ART administration in a cohort of jail inmates going in and out of jail over a nine year period.Methodology/Principal Findings
In this retrospective study, we examined inmates with HIV going in and out of jail. Inmates were categorized by patterns of ART use: continuous ART - ART both in and out of jail, intermittent ART - ART only in jail; never on ART - eligible by national guidelines, but refused ART. CD4 and HIV viral load (VL) were compared over time in these groups. Over a 9 year period, 512 inmates were studied: 388 (76%) on intermittent ART, 79 (15%) on continuous ART and 45(9%) never-on ART. In a linear mixed model analysis, inmates on intermittent ART were 1.43; 95%CI (1.03, 1.99) times and those never on ART were 2.89; 95%CI (1.71, 4.87) times more likely to have higher VL than inmates on continuous ART. Furthermore, Inmates on intermittent ART and never-on ART lost 1.60; 95%CI (1.06, 2.13) and 1.97; 95%CI (0.96, 3.00) more CD4 cells per month, respectively, compared to continuously treated inmates. The continuous ART inmates gained 0.67CD4 cells/month.Conclusions/Significance
Continuous ART therapy in jail inmate''s benefits CD4 cell counts and control of VL especially compared to those who never took ART. Although jail inmates on intermittent ART were more likely to lose CD4 cells and experience higher VL over time than those on continuous ART, CD4 cell loss was slower in these inmates as compared to inmates never on ART. Further studies are needed to evaluate whether or not intermittent ART provides some benefit in outcome if continuous ART is not possible or likely. 相似文献190.
Keertan Dheda Virginia Davids Laura Lenders Teri Roberts Richard Meldau Daphne Ling Laurence Brunet Richard van Zyl Smit Jonathan Peter Clare Green Motasim Badri Leonardo Sechi Surendra Sharma Michael Hoelscher Rodney Dawson Andrew Whitelaw Jonathan Blackburn Madhukar Pai Alimuddin Zumla 《PloS one》2010,5(3)