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941.
Harvestable, starch-storing organs of plants, such as fleshy taproots and tubers, are important agronomic products that are
also suitable target organs for use in the molecular farming of recombinant proteins due to their strong sink strength. To
exploit a promoter directing strong expression restricted to these storage organs, we isolated the promoter region (3.0 kb)
of SRD1 from sweetpotato (Ipomoea batatas cv. ‘White Star’) and characterized its activity in transgenic Arabidopsis, carrot, and potato using the β-glucuronidase (GUS) gene (uidA) as a reporter gene. The SRD1 promoter conferred root-specific expression in transgenic Arabidopsis, with SRD1 promoter activity increasing in response to exogenous IAA. A time-course study of the effect of IAA (50 μM) revealed a maximum
increase in SRD1 promoter activity at 24 h post-treatment initiation. A serial 5′ deletion analysis of the SRD1 promoter identified regions related to IAA-inducible expression as well as regions containing positive and negative elements,
respectively, controlling the expression level. In transgenic carrot, the SRD1 promoter mediated strong taproot-specific expression, as evidenced by GUS staining being strong in almost the entire taproot,
including secondary phloem, secondary xylem and vascular cambium. The activity of the SRD1 promoter gradually increased with increasing diameter of the taproot in the transgenic carrot and was 10.71-fold higher than
that of the CaMV35S promoter. The SRD1 promoter also directed strong tuber-specific expression in transgenic potato. Taken together, these results demonstrate that
the SRD1 promoter directs strong expression restricted to the underground storage organs, such as fleshy taproots and tubers, as well
as fibrous root tissues. 相似文献
942.
Universal phenotyping techniques that can discriminate among various states of biological systems have great potential. We applied 557 fluorescent library compounds to NCI's 60 human cancer cell-lines (NCI-60) to generate a systematic fluorescence phenotypic profiling data. By the kinetic fluorescence intensity analysis, we successfully discriminated the organ origin of all the 60 cell-lines. 相似文献
943.
Thalamocortical (TC) neurons are known to relay incoming sensory information to the cortex via firing in tonic or burst mode. However, it is still unclear how respective firing modes of a single thalamic relay neuron contribute to pain perception under consciousness. Some studies report that bursting could increase pain in hyperalgesic conditions while others suggest the contrary. However, since previous studies were done under either neuropathic pain conditions or often under anesthesia, the mechanism of thalamic pain modulation under awake conditions is not well understood. We therefore characterized the thalamic firing patterns of behaving mice in response to nociceptive pain induced by inflammation. Our results demonstrated that nociceptive pain responses were positively correlated with tonic firing and negatively correlated with burst firing of individual TC neurons. Furthermore, burst properties such as intra-burst-interval (IntraBI) also turned out to be reliably correlated with the changes of nociceptive pain responses. In addition, brain stimulation experiments revealed that only bursts with specific bursting patterns could significantly abolish behavioral nociceptive responses. The results indicate that specific patterns of bursting activity in thalamocortical relay neurons play a critical role in controlling long-lasting inflammatory pain in awake and behaving mice. 相似文献
944.
Seino S Watanabe S Ito N Sasaki K Shoji K Miura S Kozawa K Nakai K Sato H Kanazawa M Fukudo S 《PloS one》2012,7(3):e32913
Background
The electrophysiological properties of the brain and influence of parental bonding in childhood irritable bowel syndrome (IBS) are unclear. We hypothesized that children with chronic gastrointestinal (GI) symptoms like IBS may show exaggerated brainstem auditory evoked potential (BAEP) responses and receive more inadequate parental bonding.Methodology/Principal Findings
Children aged seven and their mothers (141 pairs) participated. BAEP was measured by summation of 1,000 waves of the electroencephalogram triggered by 75 dB click sounds. The mothers completed their Children''s Somatization Inventory (CSI) and Parental Bonding Instrument (PBI). CSI results revealed 66 (42%) children without GI symptoms (controls) and 75 (58%) children with one or more GI symptoms (GI group). The III wave in the GI group (median 4.10 interquartile range [3.95–4.24] ms right, 4.04 [3.90–4.18] ms left) had a significantly shorter peak latency than controls (4.18 [4.06–4.34] ms right, p = 0.032, 4.13 [4.02–4.24] ms left, p = 0.018). The female GI group showed a significantly shorter peak latency of the III wave (4.00 [3.90–4.18] ms) than controls (4.18 [3.97–4.31] ms, p = 0.034) in the right side. BAEP in the male GI group did not significantly differ from that in controls. GI scores showed a significant correlation with the peak latency of the III wave in the left side (rho = −0.192, p = 0.025). The maternal care PBI scores in the GI group (29 [26]–[33]) were significantly lower than controls (31 [28.5–33], p = 0.010), while the maternal over-protection PBI scores were significantly higher in the GI group (16 [12]–[17]) than controls (13 [10.5–16], p = 0.024). Multiple regression analysis in females also supported these findings.Conclusions
It is suggested that children with chronic GI symptoms have exaggerated brainstem responses to environmental stimuli and inadequate parental behaviors aggravate these symptoms. 相似文献945.
Lee SH Yoon J Shin SH Zahoor M Kim HJ Park PJ Park WS Min do S Kim HY Choi KY 《PloS one》2012,7(4):e34152
BACKGROUND: Alopecia is the common hair loss problem that can affect many people. However, current therapies for treatment of alopecia are limited by low efficacy and potentially undesirable side effects. We have identified a new function for valproic acid (VPA), a GSK3β inhibitor that activates the Wnt/β-catenin pathway, to promote hair re-growth in vitro and in vivo. METHODOLOGY/ PRINCIPAL FINDINGS: Topical application of VPA to male C3H mice critically stimulated hair re-growth and induced terminally differentiated epidermal markers such as filaggrin and loricrin, and the dermal papilla marker alkaline phosphatase (ALP). VPA induced ALP in human dermal papilla cells by up-regulating the Wnt/β-catenin pathway, whereas minoxidil (MNX), a drug commonly used to treat alopecia, did not significantly affect the Wnt/β-catenin pathway. VPA analogs and other GSK3β inhibitors that activate the Wnt/β-catenin pathway such as 4-phenyl butyric acid, LiCl, and BeCl(2) also exhibited hair growth-promoting activities in vivo. Importantly, VPA, but not MNX, successfully stimulate hair growth in the wounds of C3H mice. CONCLUSIONS/ SIGNIFICANCE: Our findings indicate that small molecules that activate the Wnt/β-catenin pathway, such as VPA, can potentially be developed as drugs to stimulate hair re-growth. 相似文献
946.
Nonsteroidal anti-inflammatory drug-activated gene-1 (NAG-1) is induced by nonsteroidal anti-inflammatory drugs and possesses proapoptotic and antitumorigenic activities. Although tolfenamic acid (TA) induces apoptosis in head and neck cancer cells, the relationship between NAG-1 and TA has not been determined. This study investigated the induction of apoptosis in head and neck cancer cells treated by TA and the role of NAG-1 expression in this induction. TA reduced head and neck cancer cell viability in a dose-dependent manner and induced apoptosis. The induced apoptosis was coincident with the expression of NAG-1. Overexpression of NAG-1 enhanced the apoptotic effect of TA, whereas suppression of NAG-1 expression by small interfering RNA attenuated TA-induced apoptosis. TA significantly inhibited tumor formation as assessed by xenograft models, and this result accompanied the induction of apoptotic cells and NAG-1 expression in tumor tissue samples. Taken together, these results demonstrate that TA induces apoptosis via NAG-1 expression in head and neck squamous cell carcinoma, providing an additional mechanistic explanation for the apoptotic activity of TA. 相似文献
947.
YR Kim JS Kim YH Min DH Yoon HJ Shin YC Mun Y Park YR Do SH Jeong JS Park SY Oh S Lee EK Park JS Jang WS Lee HW Lee H Eom JS Ahn J Jeong SK Baek SJ Kim WS Kim C Suh 《Journal of hematology & oncology》2012,5(1):49
ABSTRACT: BACKGROUND: The objective of this study was to identify prognostic factors for survival in patients with primary diffuse large B-cell lymphoma (DLBCL) of the adrenal gland. METHODS: Thirty one patients diagnosed with primary adrenal DLBCL from 14 Korean institutions and treated with R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine and prednisone) were analyzed. RESULTS: Complete remission (CR) and overall response rate after R-CHOP chemotherapy were 54.8% and 87.0%. The 2-year estimates of overall survival (OS) and progression-free survival (PFS) were 68.3% and 51.1%. In patients achieving CR, significant prolongations of OS (P = 0.029) and PFS (P = 0.005) were observed. Ann Arbor stage had no influence on OS. There was no significant difference in OS between patients with unilateral involvement of adrenal gland and those with bilateral involvement. When staging was modified to include bilateral adrenal involvement as one extranodal site, early stage (I or II) significantly correlated with longer OS (P = 0.021) and PFS (P <0.001). CONCLUSIONS: Contrary to prior reports, our data suggests that outcomes of primary adrenal DLBCL are encouraging using a regimen of R-CHOP, and that achieving CR after R-CHOP is predictive of survival. Likewise, our modified staging system may have prognostic value. 相似文献
948.
The pitch-loblolly pine hybrid (Pinus rigida × P. taeda) has useful characteristics of the parents, but its exploitation is hindered by restrictions of conventional breeding and
propagation methods. This study was undertaken to establish an effective in vitro system for propagating pitch-loblolly hybrid
pine through somatic embryogenesis and to unravel the relationship between the efficiency of embryogenic tissue initiation
and zygotic embryo development. To initiate embryogenic tissue, megagametophytes of developing seeds were used as explants.
Seeds were collected weekly, examined, and tested during June and July 2004. The medium and seed collection date were the
most important factors for the successful somatic embryogenesis of P. rigida × P. taeda. Five embryogenic lines were obtained using a modified P. taeda basal medium, and the highest initiation rate was 0.55%, for seeds collected in 2 weeks, between July 3 and 16. Histological
observation revealed that zygotic embryos of those seeds were mostly at the proembryonic stage or in transition to precotyledonary
stages. For the successful maturation of somatic embryos, abscisic acid and gellan gum were needed in the medium. The results
show that, although further tests and development are required, somatic embryogenesis could provide a viable option for propagating
P. rigida × P. taeda hybrids. 相似文献
949.
ABSTRACT: BACKGROUND: In sleep efficiency monitoring system, actigraphy is the simplest and most commonly used device. However, low specificity to wakefulness of actigraphy was revealed in previous studies. In this study, we assumed that sleep/wake estimation using actigraphy and electromyography (EMG) signals would show different patterns. Furthermore, each EMG pattern in two states (sleep, wake during sleep) was analysed. Finally, we proposed two types of method for the estimation of sleep/wake patterns using only EMG signals from anterior tibialis muscles and the results were compared with PSG data. METHODS: Seven healthy subjects and five patients (2 obstructive sleep apnea, 3 periodic limb movement disorder) participated in this study. Night time polysomnography (PSG) recordings were conducted, and electrooculogram, EMG, electroencephalogram, electrocardiogram, and respiration data were collected. Time domain analysis and frequency domain analysis were applied to estimate the sleep/wake patterns. Each method was based on changes in amplitude or spectrum (total power) of anterior tibialis electromyography signals during the transition from the sleep state to the wake state. To obtain the results, leave-one-out-cross-validation technique was adopted. RESULTS: Total sleep time of the each group was about 8 hours. For healthy subjects, the mean epoch-by-epoch results between time domain analysis and PSG data were 99%, 71%, 80% and 0.64 (sensitivity, specificity, accuracy and kappa value), respectively. For frequency domain analysis, the corresponding values were 99%, 73%, 81% and 0.67, respectively. Absolute and relative differences between sleep efficiency index from PSG and our methods were 0.8 and 0.8% (for frequency domain analysis). In patients with sleep-related disorder, our proposed methods revealed the substantial agreement (kappa > 0.61) for OSA patients and moderate or fair agreement for PLMD patients. CONCLUSIONS: The results of our proposed methods were comparable to those of PSG. The time and frequency domain analyses showed the similar sleep/wake estimation performance. 相似文献
950.
Min Hwa Shin Ming Yuan Hao Zhang Joseph B. Margolick Mihoko Kai 《Cell cycle (Georgetown, Tex.)》2012,11(9):1796-1803
Upon genotoxic stress and during normal S phase, ATM phosphorylates the checkpoint clamp protein Rad9 in a manner that depends on Ser272. Ser272 is the only known ATM-dependent phosphorylation site in human Rad9. However, Ser272 phosphorylation is not required for survival or checkpoint activation after DNA damage. The physiological function of Ser272 remains elusive. Here, we show that ATM-dependent Rad9Ser272 phosphorylation requires the MRN complex and controls repair pathways. Furthermore, the mutant cells accumulate large numbers of chromosome breaks and induce gross chromosomal rearrangements. Our findings establish a new and unexpected role for ATM: it phosphorylates the checkpoint clamp in order to control repair pathways, thereby maintaining genomic integrity during unperturbed cell cycle and upon DNA damage. 相似文献