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101.
A new soil mite species, Quadroppia (Coronoquadroppia) sezeki sp. n., is described. Adult mites were recorded from moss under a pine tree from a pine forest. The new species differs from
the other species of the subgenus by bearing epimera III+IV with a wide key hole shaped inner border and the shape of frontal
appendage of rostrum. The morphological features of the new species are also compared with those present in closely related
species. 相似文献
102.
Mohammad Raish Varinderpal S Dhillon Arif Ahmad Mushtaq Ahmad Ansari Shahid Mudassar Mohammad Shahid Vineeta Batra Pawan Gupta Bhudev Chandra Das NK Shukla Syed Akhtar Husain 《Translational oncology》2009,2(4):264-270
BACKGROUND: Aberrant DNA methylation has been recognized in human breast carcinogenesis as a common molecular alteration associated with the loss of expression of a number of key regulatory genes. The present study was undertaken to determine whether methylation and expression of p16 and FHIT genes would correlate with the estrogen receptor (ER) and progesterone receptor (PR) status. METHODS: Methylation-specific polymerase chain reaction, messenger RNA (mRNA) expression analysis, immunohistochemistry, and Western blot analysis were performed to study the methylation of p16 and FHIT genes in 351 pairs of malignant/normal breast tissues. We examined the expression of ER and PR in those specimens by immunohistochemistry. Mutations of p16 and FHIT genes in tumors were detected by direct sequencing. RESULTS: The frequency of hypermethylation was 31.9% and 36.8% in p16 and FHIT genes, respectively, and showed significant harmony in concordant hypermethylation (P < .0001). In postmenopausal patients, methylation frequency in both genes is significantly higher in poorly and moderately differentiated tumors. Loss of protein expression of p16 and FHIT in 77 and 74 tumors, respectively, is associated with their methylation status in premenopausal women. CONCLUSION: We did not find any significant differences in tumor-related gene methylation patterns relevant to both ER and PR status of breast tumors. 相似文献
103.
B. Karabulut M.K. Gul B. Karaca G. Gorumlu S. Uzunoglu Y. Baran 《Cell biology international》2009,33(2):239-246
Docetaxel, a semi-synthetic taxane analogue, is used effectively in the treatment of metastatic prostate cancer. Zoledronic acid, the most potent member of bisphosphonates, has shown pleiotropic anti-tumoral effects on prostate cancer cells. We have explored the possible additive/synergistic effects and the apoptotic pathways induced by combination treatment of docetaxel and zoledronic acid in hormone and drug refractory, PC-3 and DU-145 prostate cancer cells. Combination of docetaxel and zoledronic acid synergistically inhibits cell growth in PC-3 and DU-145 cells. Moreover, this effect was due to downregulation of antiapoptotic protein Bcl-2 in PC-3 and DU-145 cells. In conclusion, docetaxel/zoledronic acid combination is potentially a novel and effective approach for the treatment of prostate cancer. 相似文献
104.
Bruce J West Artur Maciejewski Miroslaw Latka Tadeusz Sebzda Zbigniew Swierczynski Sylwia Cybulska-Okolow Eugeniusz Baran 《Journal of applied physiology》2006,101(5):1425-1431
We present a novel approach to the analysis of fluctuations in human myoelectrical gastric activity measured noninvasively from the surface of the abdomen. The time intervals between successive maxima of the wavelet transformed quasi-periodic electrogastrographic waveform define the gastric rate variability (GRV) time series. By using the method of average wavelet coefficients, the statistical fluctuations in the GRV signal in healthy individuals are determined to scale in time. Such scaling was previously found in a variety of physiological phenomena, all of which support the hypothesis that physiological dynamics utilize fractal time series. We determine the scaling index in a cohort of 17 healthy individuals to be 0.80 +/- 0.14, which compared with a set of surrogate data is found to be significant at the level P < 0.01. We also determined that the dynamical pattern, so evident in the spectrum of average wavelet coefficients of the GRV time series of healthy individuals, is significantly reduced in a cohort of systemic sclerosis patients having a scaling index 0.64 +/- 0.17. These results imply that the long-term memory in GRV time series is significantly reduced from healthy individuals to those with systemic sclerosis. Consequently, this disease degrades the complexity of the underlying gastrointestinal control system and this degradation is manifest in the loss of scaling in the GRV time series. 相似文献
105.
Richard C. Crist Jacquelyn J. Roth Amy A. Baran Benjamin J. McEntee Linda D. Siracusa Arthur M. Buchberg 《Mammalian genome》2010,21(9-10):450-457
The adenomatous polyposis coli (APC) gene is known to act as a tumor suppressor gene in both sporadic and hereditary colorectal cancer by negatively regulating WNT signaling. Familial adenomatous polyposis (FAP) patients develop intestinal polyps due to the presence of a single germline mutation in APC. The severity of the FAP phenotype is a function of the position of the APC mutation, indicating a complex role for APC that extends beyond the canonical WNT pathway. APC encodes a large protein with multiple functional domains, including an armadillo repeat domain that has been linked to protein–protein interactions. To determine the effect of the armadillo repeat domain on intestinal tumorigenesis, we generated a congenic mouse line (Apc Δ242 ) carrying a gene trap cassette between exons 7 and 8 of the murine Apc gene. Apc Δ242/+ mice express a truncated Apc product lacking the armadillo repeat domain as part of a fusion protein with β-geo. Expression of the fusion product was confirmed by X-gal staining, ensuring that Apc Δ242 is not a null allele. In contrast, Apc Min/+ mice produce a truncated Apc product that contains an intact armadillo repeat domain. On the C57BL/6J background, Apc Δ242/+ mice develop more polyps than do Apc Min/+ mice along the entire length of the small intestine; however, polyps were significantly smaller in Apc Δ242/+ mice. In addition, polyp multiplicity in Apc Δ242/+ mice is affected by polymorphisms between inbred strains. These data suggest that the armadillo repeat domain of the Apc protein suppresses tumor initiation in the murine intestine while also promoting tumor growth. 相似文献
106.
This is the very first report that suggests high pregnancy rates can be obtained with use of the Doublesynch protocol in anestrous dairy cows. Recently, a new synchronization method has been developed (Doublesynch) that resulted in synchronized ovulations both after the first and second gonadotropin-releasing hormone (GnRH) treatments. It was suggested that this protocol has the potential to increase the pregnancy rates in primiparous dairy cows. The aim of the current study was to confirm the success of the Doublesynch protocol and further to investigate the effect of this method on pregnancy rates in anestrous cows. Lactating primiparous Holstein (Bos taurus) cows (n = 165) between 60 and 172 d postpartum were monitored twice with 10-d intervals (on Days -10 and 0) by ultrasonography, and blood samples were collected. Cows were classified as anestrous if both blood samples had progesterone (P4) concentration <1 ng/mL and as cyclic if at least one of the two samples had P4 concentration ≥1 ng/mL. Cyclic cows were classified again as cyclic-high P4 (having an active corpus luteum) if the second blood samples had P4 concentrations ≥1 ng/mL and as cyclic-low P4 if P4 concentrations were <1 ng/mL on Day 0. Then, the cows classified as anestrous (n = 51), cyclic-high P4 (n = 63), or cyclic-low P4 (n = 51) were put into two treatment groups (Ovsynch or Doublesynch) randomly to establish six groups. Cows in the Ovsynch group were administered a GnRH (lecirelin 50 μg, im) on Day 0, PGF (Prostaglandin F2 alpha, D-cloprostenol 0.150 mg, im) on Day 7, and a second dose of GnRH 48 h later. Cows in the Doublesynch group were administered a PGF on Day 0, GnRH on Day 2, a second PGF on Day 9, and a second GnRH on Day 11. Timed artificial insemination (TAI) was performed 16 to 20 h after the second GnRH in both treatment groups. Pregnancy diagnosis was conducted (by ultrasonography) 45 ± 5 d after TAI. In anestrous cows and those with high and low progesterone concentration at treatment onset, Doublesynch treatment led to markedly increased pregnancy rates with respect to Ovsynch treatment (P < 0.05). On the overall analysis of data, it was revealed that the Doublesynch method increased pregnancy rates by 43 percentage units (29.8% vs. 72.8%, P < 0.0001) in relation to Ovsynch. Pregnancy rates of cows having small, medium, or large follicles at the day of second GnRH administration were similar in the Doublesynch group (70.4%, 85.2%, and 63.0%, respectively; P > 0.05), whereas pregnancy rates reduced dramatically as follicle size increased in the Ovsynch group, particularly in cows with follicles greater than 16 mm (45.5%, 28.1%, and 5.3%, respectively; P < 0.05). Our results confirm and support observations that the Doublesynch protocol increases the pregnancy rates in postpartum primiparous cows as reported previously. Our data also demonstrate that the Doublesynch method increases the pregnancy rates in anestrous cows. Thus, these data suggest that the Doublesynch protocol can be used to obtain satisfactory pregnancy rates after TAI in both anestrous and cycling primiparous dairy cows regardless of stage of estrous cycle. 相似文献
107.
Pollen morphology of 10 taxa from Turkey, four of them endemic, belonging to the genus Petrorhagia (Caryophyllaceae), P. alpina subsp. alpina, P. alpina subsp. olympica, P. cretica, P. dubia, P. hispidula, P. lycica, P. pamphylica, P. peroninii, P. prolifera and P. saxifraga, has been investigated using light (LM) and scanning electron (SEM) microscopy. Pollen morphology differences among these
taxa have been determined. The pollen type of investigated taxa is polyporate (12–22-porate), sphaeroidal, the exine exhibits
a tectate structure and a microechinate ornamentation. Petrorhagia alpina subsp. alpina has the smallest pollen grain diameter (18.57 μm) and P. dubia the largest one (37.80 μm). The number of pores ranges from 12 (in P. dubia and P. saxifraga) to 22 (in P. alpina subsp. alpina and P. alpina subsp. olympica and P. hispidula) with a minimum pore diameter of 2.37 μm in P. alpina subsp. alpina and a maximum pore diameter of 4.23 μm in P. peroninii. The exine thickness ranges from 1.73 μm in P. saxifraga to 3.78 μm in P. pamphylica. In this study, the systematic implications are discussed in the light of palynological results. 相似文献
108.
Stefano Crosignani Marc Missotten Christophe Cleva Ruggero Dondi Yann Ratinaud Yves Humbert Ashis Baran Mandal Agnès Bombrun Christine Power André Chollet Amanda Proudfoot 《Bioorganic & medicinal chemistry letters》2010,20(12):3614-3617
The discovery of a novel series of CXCR3 antagonists is described. Starting from an HTS positive, iterative optimization gave potent compounds (IC50 15 nM in a chemotaxis assay). The strategy employed to improve the metabolic stability of these derivatives is described. 相似文献
109.
Batch kinetic studies on growth of salt tolerant Pseudomonas aeruginosa secreting protease in a biocalorimeter 总被引:1,自引:0,他引:1
Surianarayanan Mahadevan Balaji Dhandapani Senthilkumar Sivaprakasam Asit Baran Mandal 《Biotechnology and Bioprocess Engineering》2010,15(4):670-675
Biocalorimetry has proved to be an efficient tool for studying the energetics involved in several biochemical reactions. In this study, biocalorimetry was employed to simultaneously analyze biokinetics and bioenergetics involved during cultivation of a salt tolerant Pseudomonas aeruginosa for the production of alkaline protease. Batch experiments were performed in a bench scale biocalorimeter for alkaline protease production by P. aeruginosa using optimized process conditions. Tessier’s double substrate growth model was found to provide a good fit for the growth of P. aeruginosa in the biocalorimeter, and the biokinetic parameters were estimated. The heat flow profile resulting from metabolic activity of P. aeruginosa was shown to accurately depict both the kinetics of cell growth and protease production. Biokinetic and bioenergetic analysis on the growth of P. aeruginosa revealed that peptone is preferentially used as the substrate for its intracellular activities and glycerol acts as an energy source for its growth metabolism. 相似文献
110.
Induced cell death of preimplantation mouse embryos cultured in vitro evaluated by comet assay 总被引:2,自引:0,他引:2
The occurrence of apoptosis in mouse preimplantation embryos was analyzed using DNA staining (Hoechst 33342, PI) for the visualization of nuclear changes and by the comet assay, a single-cell gel electrophoresis assay, modified for the analysis of blastocysts. Mouse preimplantation embryos isolated 56 h after superovulation were cultured in vitro for 64 h. Apoptosis was induced by treatment with camptothecin and actinomycin D during the first 15 h of culture. After culture in vitro, a number of embryos were stained and analyzed using morphological criteria. The remaining embryos were examined using the comet assay for the detection of DNA fragmentation. The proportion of damaged embryos in experimental groups, in comparison to controls, was dependent on the dose of apoptosis inductor. At high doses (camptothecin, microg/ml and actinomycin D, 0.05 microg/ml) over 90% (chi-square test, P<0.001) of embryos had apoptotic comets, at medium doses (camptothecin, 0.01 microg/ml and actinomycin D, 0.005 microg/ml) comets appeared only in 30-70% of embryos (camptothecin, P<0.01 and actinomycin D, P<0.001). At low doses (camptothecin, 0.001 microg/ml and actinomycin D, 0.0005 microg/ml) the increase in damaged embryos was not statistically significant. Hoechst/PI staining showed a higher percentage of damaged blastomeres at high doses. Morphological changes correlated with the outcome of the comet assay. Our results show that comet assay is an appropriate method for studying apoptosis in preimplantation embryos, and it appears to be more sensitive than the classically used morphological analyses. 相似文献