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31.
The objective of this study was to examine the effect of cytochalasin B (CB) and/or demecolcine (Dc) on the remodeling of donor nuclei, nuclear ploidy, and development of somatic cell nuclear transfer (SCNT) and parthenogenetic (PA) pig embryos. SCNT and PA oocytes were either untreated (control), or treated with CB, Dc, or both CB and Dc after electric activation, and then cultured or transferred to surrogates. In SCNT, blastocyst formation was higher after treatment with CB and/or Dc (26–28%) than in the controls (16%). The number of oocytes that formed a single pronucleus (PN) was higher after treatment with Dc (86%) and CB + Dc (86%) than under control conditions (44%) or after treatment with CB (63%). In PA, blastocyst formation was higher after CB treatment (47%) than under control conditions (28%), while the formation of a single PN was higher after treatment with Dc (88%) and CB + Dc (84%) compared to controls (34%). The rate of formation of diploid embryos was higher after treatment with Dc and CB + Dc than under control conditions. Dc treatment resulted in a farrowing rate of 50% with 1.1% production efficiency, while controls showed a farrowing rate of 37.5% and a production efficiency of 0.7%. The results of our study demonstrate that post‐activation treatment with Dc improves preimplantation development and supports normal in vivo development of SCNT pig embryos, probably because Dc induces formation of a single PN and this leads to normal nuclear ploidy. Mol. Reprod. Dev. 76: 611–619, 2009. © 2008 Wiley‐Liss, Inc.  相似文献   
32.
Cloning of a New Bacillus thuringiensis cry1I-Type CrystalProtein Gene   总被引:1,自引:0,他引:1  
A new cry1I-type gene, cry1Id1, was cloned from a B. thuringiensis isolate, and its nucleotide sequence was determined. The deduced amino acid sequence of Cry1Id1 is 89.7%, 87.2%, and 83.4% identical to the Cry1Ia, Cry1Ib, and Cry1Ic proteins, respectively. The upstream sequence of the cry1Id1 structural gene was not functional as promoter in B. subtilis. The Cry1Id1 protein, purified from recombinant E. coli cells, had a toxicity comparable to that of Cry1Ia against Plutella xylostella, but it was significantly less active than Cry1Ia against Bombyx mori. Cry1Id1 was not active against the coleopteran insect, Agelastica coerulea. Received: 19 January 2000 / Accepted: 22 February 2000  相似文献   
33.

Introduction

This study tested the effectiveness of moxibustion on pain and function in chronic knee osteoarthritis (KOA) and evaluated safety.

Methods

A multi-centre, non-blinded, parallel-group, randomised controlled trial compared moxibustion with usual care (UC) in KOA. 212 South Korean patients aged 40–70 were recruited from 2011–12, stratified by mild (Kellgren/Lawrence scale grades 0/1) and moderate-severe KOA (grades 2/3/4), and randomly allocated to moxibustion or UC for four weeks. Moxibustion involved burning mugwort devices over acupuncture and Ashi points in affected knee(s). UC was allowed. Korean Western Ontario and McMaster Universities Questionnaire (K-WOMAC), Short Form 36 Health Survey (SF-36v2), Beck Depression Inventory (BDI), physical performance test, pain numeric rating scale (NRS) and adverse events were evaluated at 5 and 13 weeks. K-WOMAC global score at 5 weeks was the primary outcome.

Results

102 patients (73 mild, 29 moderate-severe) were allocated to moxibustion, 110 (77 mild, 33 moderate-severe) to UC. K-WOMAC global score (moxibustion 25.42+/−SD 19.26, UC 33.60+/−17.91, p<0.01, effect size  = 0.0477), NRS (moxibustion 44.77+/−22.73, UC 56.23+/−17.71, p<0.01, effect size  = 0.0073) and timed-stand test (moxibustion 24.79+/−9.76, UC 25.24+/−8.84, p = 0.0486, effect size  = 0.0021) were improved by moxibustion at 5 weeks. The primary outcome improved for mild but not moderate-severe KOA. At 13 weeks, moxibustion significantly improved the K-WOMAC global score and NRS. Moxibustion improved SF-36 physical component summary (p = 0.0299), bodily pain (p = 0.0003), physical functioning (p = 0.0025) and social functioning (p = 0.0418) at 5 weeks, with no difference in mental component summary at 5 and 13 weeks. BDI showed no difference (p = 0.34) at 5 weeks. After 1158 moxibustion treatments, 121 adverse events included first (n = 6) and second degree (n = 113) burns, pruritus and fatigue (n = 2).

Conclusions

Moxibustion may improve pain, function and quality of life in KOA patients, but adverse events are common. Limitations included no sham control or blinding.

Trial Registration

Clinical Research Information Service (CRIS) KCT0000130  相似文献   
34.
Huh Y  Bhatt R  Jung D  Shin HS  Cho J 《PloS one》2012,7(1):e30699
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   
35.
Kim DM  Yun NR  Neupane GP  Shin SH  Ryu SY  Yoon HJ  Wie SH  Kim WJ  Lee CY  Choi JS  Yang TY 《PloS one》2011,6(8):e22731

Background

Scrub typhus is an infectious disease caused by Orientia tsutsugamushi. The differences in virulence of O. tsutsugamushi prototypes in humans are still unknown. We investigated whether there are any differences in the clinical features of the Boryoung and Karp genotypes.

Methodology/Principal Findings

Patients infected with O. tsutsugamushi, as Boryoung and Karp clusters, who had visited 6 different hospitals in southwestern Korea were prospectively compared for clinical features, complications, laboratory parameters, and treatment responses. Infected patients in the Boryoung cluster had significantly more generalized weakness, eschars, skin rashes, conjunctival injection, high albumin levels, and greater ESR and fibrinogen levels compared to the Karp cluster. The treatment response to current antibiotics was significantly slower in the Karp cluster as compared to the Boryoung cluster.

Conclusion

The frequency of occurrence of eschars and rashes may depend on the genotype of O. tsutsugamushi.  相似文献   
36.
Biliary atresia (BA) is a rare and serious liver disease in newborn infants. Previously, we reported that non-parenchymal cell (NPC) fractions from cirrhotic liver of BA may contain hepatic stem/progenitor cells in primary culture of NPC fractions. In this study, NPC fractions were subjected to primary or passage culture and found that clusters of hepatocyte-like cells appear even without adding hepatocyte growth factor (HGF) to the culture medium, but not in their passage culture used as a control. Based on these findings, conditioned media (CMs) were collected and soluble factors in the CMs were analyzed in order to elucidate the mechanism of the appearance of hepatocyte-like cells or their clusters. A large amount of active HGF consisting of α and β chains was detected in CMs derived from primary culture, but not in CMs from passage culture, as determined by western blot analysis, bone morphogenetic protein (BMP)-4, oncostatin M (OSM), and transforming growth factor (TGF)-β1 were not detected in any of the CMs. The number of hepatocyte-like cells in primary culture tended to decrease following treatment with the HGF receptor c-Met inhibitor, SU11274 in a dose-dependent manner. Furthermore, the clusters of hepatocyte-like cells tended to increase in size and number when freshly isolated NPC fractions were cultured in the presence of 10% of CMs collected after 3–4 wk of primary culture. In conclusion, these findings indicate that CMs derived from primary culture of NPC fractions of BA liver contain a large amount of active HGF, which may activate hepatic stem/progenitor cells and promote the appearance of hepatocyte-like cells or their clusters through HGF/c-Met signaling. The present study would lead to cell therapy using the patient’s own cells for the treatment of BA.  相似文献   
37.
The domestic chicken (Gallus gallus) is an important model for research in developmental biology because its embryonic development occurs in ovo. To examine the mechanism of embryonic germ cell development, we constructed proteome map of gonadal primordial germ cells (gPGCs) from chicken embryonic gonads. Embryonic gonads were collected from 500 embryos at 6 days of incubation, and the gPGCs were cultured in vitro until colony formed. After 7-10 days in culture, gPGC colonies were separated from gonadal stroma cells (GSCs). Soluble extracts of cultured gPGCs were then fractionated by two-dimensional gel electrophoresis (pH 4-7). A number of protein spots, including those that displayed significant expression levels, were then identified by use of matrix-assisted laser desorption/ionization-time of flight (MALDI-TOF) mass spectrometry and LC-MS/MS. Of the 89 gPGC spots examined, 50 yielded mass spectra that matched avian proteins found in on-line databases. Proteome map of this type will serve as an important reference for germ cell biology and transgenic research.  相似文献   
38.
Mycoleptodonoides aitchisonii (Berk.) Maas Geest. is a culinary mushroom that is recognized as both a nutritious food and an excellent source of bioactive compounds. The purpose of this study was to investigate the antioxidant and antidiabetic properties of M. aitchisonii (MA) both in vitro and in vivo. Total oxyradical scavenging capacity (TOSC) assays revealed that fruit-body extracts had higher antioxidant capacity than mycelial extracts, 0.9-fold higher as measured by peroxynitrite (PN) scavenging assay, 3.7-fold higher as measured by peroxyl radical (PR) scavenging assay, and 1.6-fold as measured by hydroxyl radical (HR) scavenging assay, respectively. The assay of Akt phosphorylation, which is inhibited by Interleukin 6 (IL-6) in the signal transduction pathway for diabetes, was employed to evaluate the antidiabetic activity. Fruit-body extracts significantly increased Akt phosphorylation according to the fruit-body extract concentration, with a maximum increment of 77% at a concentration of 100 μg/mL compared to 51.4% decrement caused by IL-6, but there was no effect of mycelial extracts. Treatment with 5% MA fruit-body powder and streptozotocin (STZ) decreased the blood sugar level to 233.8 mg/dL in diabetic mice compared to 333.8 mg/dL after treatment with STZ alone. Additionally, MA treatment lowered total cholesterol (TC), triglyceride (TG), and LDL-cholesterol levels, while it increased the HDL-cholesterol level. All these findings indicate that fruit-body of M. aitchisonii has potential utility in preventing various diseases such as disorders of sugar and lipid metabolism.  相似文献   
39.
The coryneforms are a diverse group of bacteria which includes animal and plant pathogens as well as non-pathogenic bacteria. Although they are of significant economic and health importance, their genetics is poorly understood. The development of genetic engineering techniques for coryneforms and initial gene cloning studies are discussed.  相似文献   
40.
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