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1.
Phyu Phyu Khine Zar Satoshi Yano Kozue Sakao Fumio Hashimoto Takayuki Nakano Makoto Fujii 《Bioscience, biotechnology, and biochemistry》2013,77(10):1731-1737
Fresh loquat leaves have been used as folk health herb in Asian countries for long time, although the evidence supporting their functions is still minimal. This study aimed to clarify the chemopreventive effect of loquat tea extract (LTE) by investigating the inhibition on proliferation, and underlying mechanisms in human promyelocytic leukemia cells (HL-60). LTE inhibited proliferation of HL-60 in a dose-dependent manner. Molecular data showed that the isolated fraction of LTE induced apoptosis of HL-60 as characterized by DNA fragmentation; activation of caspase-3, -8, and -9; and inactivation of poly(ADP)ribose polymerase. Moreover, LTE fraction increased the ratio of pro-apoptotic Bcl-2-associated X protein (Bax)/anti-apoptotic myeloid cell leukemia 1 (Mcl-1) that caused mitochondrial membrane potential loss and cytochrome c released to cytosol. Thus, our data indicate that LTE might induce apoptosis in HL-60 cells through a mitochondrial dysfunction pathway. These findings enhance our understanding for chemopreventive function of loquat tea. 相似文献
2.
Charles M. Peters Andrew Henderson U Myint Maung U Saw Lwin U Tin Maung Ohn U Kyaw Lwin U Tun Shaung 《Economic botany》2007,61(1):3-13
Although Myanmar exports millions of dollars of rattan cane each year, the last systematic treatment of rattans in this country
was done over 100 years ago, and virtually nothing has been written about the collection and trade of this important forest
resource. Here we report the results from a study of rattans in the Hukaung Valley Tiger Reserve in northern Myanmar. A total
of 15 species of rattan were encountered; seven species are new records for Myanmar and two species are new to science. Inventory
transects revealed that the density of commercial rattans in local forests averages 40.5 canes ≽4m long/hectare. Populations
of all species appear to be actively regenerating. The current pattern of rattan exploitation, however, is largely uncontrolled
and will eventually lead to resource depletion unless some form of management is implemented. 相似文献
3.
Libraty DH Myint KS Murray CK Gibbons RV Mammen MP Endy TP Li W Vaughn DW Nisalak A Kalayanarooj S Hospenthal DR Green S Rothman AL Ennis FA 《PLoS neglected tropical diseases》2007,1(3):e111
Background
Leptospirosis is an emerging zoonosis that is often under-recognized in children and commonly confused with dengue in tropical settings. An enhanced ability to distinguish leptospirosis from dengue in children would guide clinicians and public health personnel in the appropriate use of limited healthcare resources.Methodology/Principal Findings
We conducted a prospective, hospital-based, study of children with acute febrile illnesses and dengue in Thailand. Among the children without dengue, we identified those with leptospirosis using anti-leptospira IgM and microscopic agglutination titers in paired acute and convalescent blood samples. We then performed a case-control comparison of symptoms, signs, and clinical laboratory values between children with leptospirosis and dengue.In a semi-rural region of Thailand, leptospirosis accounted for 19% of the non-dengue acute febrile illnesses among children presenting during the rainy season. None of the children with leptospirosis were correctly diagnosed at the time of hospital discharge, and one third (33%) were erroneously diagnosed as dengue or scrub typhus. A predictive model to distinguish pediatric leptospirosis from dengue was generated using three variables: the absolute neutrophil count, plasma albumin, and aspartate aminotransferase levels in the first 72 hours of illness.Conclusions/Significance
Unrecognized leptospirosis can be a significant cause of “dengue-like” febrile illness in children. Increased awareness of pediatric leptospirosis, and an enhanced ability to discriminate between leptospirosis and dengue early in illness, will help guide the appropriate use of healthcare resources in often resource-limited settings. 相似文献4.
Nitrogen-15 Carr-Purcell-Meiboom-Gill (CPMG) transverse relaxation experiment are widely used to characterize protein backbone dynamics and chemical exchange parameters. Although an accurate value of the transverse relaxation rate, R(2), is needed for accurate characterization of dynamics, the uncertainty in the R(2) value depends on the experimental settings and the details of the data analysis itself. Here, we present an analysis of the impact of CPMG pulse phase alternation on the accuracy of the (15)N CPMG R(2). Our simulations show that R(2) can be obtained accurately for a relatively wide spectral width, either using the conventional phase cycle or using phase alternation when the r.f. pulse power is accurately calibrated. However, when the r.f. pulse is miscalibrated, the conventional CPMG experiment exhibits more significant uncertainties in R(2) caused by the off-resonance effect than does the phase alternation experiment. Our experiments show that this effect becomes manifest under the circumstance that the systematic error exceeds that arising from experimental noise. Furthermore, our results provide the means to estimate practical parameter settings that yield accurate values of (15)N transverse relaxation rates in the both CPMG experiments. 相似文献
5.
Cohen E Koch L Thu KM Rahamim Y Aluma Y Ilan M Yarden O Carmeli S 《Bioorganic & medicinal chemistry》2011,19(22):6587-6593
Three novel meroterpenoids, insuetolides A-C (1-3) and four drimane sesquiterpenes, the new (E)-6-(4'-hydroxy-2'-butenoyl)-strobilactone A (4) and the known 2α, 9α, 11-trihydroxy-6-oxodrim-7-ene (5), strobilactone A (6) and (E,E)-6-(6',7'-dihydroxy-2',4'-octadienoyl)-strobilactone A (7), were isolated from the EtOAc extract of the culture medium of the marine-derived fungus Aspergillus insuetus (OY-207), which was isolated from the Mediterranean sponge Psammocinia sp. The structures of the compounds were determined by spectroscopic methods. Insuetolides A-C reveal a new carbon skeleton derived from the cyclization of farnesyl and 3, 5-dimethylorsellinic acid. Compounds 1, 6, and 7 exhibited anti-fungal activity towards Neurospora crassa with MIC values of 140, 242, and 162 μM, respectively; and compounds 3, 4, and 7 exhibited mild cytotoxicity towards MOLT-4 human leukemia cells. 相似文献
6.
Doris Riether Renée Zindell Jennifer A. Kowalski Brian N. Cook Jörg Bentzien Stéphane De Lombaert David Thomson Stanley Z. Kugler Donna Skow Leslie S. Martin Ernest L. Raymond Hnin Hnin Khine Kathy O’Shea Joseph R. Woska Deborah Jeanfavre Rosemarie Sellati Kerry L.M. Ralph Jennifer Ahlberg Gabriel Labissiere Mohammed A. Kashem Hidenori Takahashi 《Bioorganic & medicinal chemistry letters》2009,19(6):1588-1591
Benzamide 1 demonstrated good potency as a selective ITK inhibitor, however the amide moiety was found to be hydrolytically labile in vivo, resulting in low oral exposure and the generation of mutagenic aromatic amine metabolites. Replacing the benzamide with a benzylamine linker not only addressed the toxicity issue, but also improved the cellular and functional potency as well as the drug-like properties. SAR studies around the benzylamines and the identification of 10n and 10o as excellent tools for proof-of-concept studies are described. 相似文献
7.
X protein of hepatitis B virus inhibits Fas-mediated apoptosis and is associated with up-regulation of the SAPK/JNK pathway 总被引:34,自引:0,他引:34
Diao J Khine AA Sarangi F Hsu E Iorio C Tibbles LA Woodgett JR Penninger J Richardson CD 《The Journal of biological chemistry》2001,276(11):8328-8340
The X protein from a chronic strain of hepatitis B virus (HBx) was determined to inhibit Fas-mediated apoptosis and promote cell survival. Fas-mediated apoptosis is the major cause of hepatocyte damage during liver disease. Experiments demonstrated that cell death caused by anti-Fas antibodies was blocked by the expression of HBx in human primary hepatocytes and mouse embryo fibroblasts. This effect was also observed in mouse erythroleukemia cells that lacked p53, indicating that protection against Fas-mediated apoptosis was independent of p53. Components of the signal transduction pathways involved in this protection were studied. The SAPK/JNK pathway has previously been suggested to be a survival pathway for some cells undergoing Fas-mediated apoptosis, and kinase assays showed that SAPK activity was highly up-regulated in cells expressing the HBx protein. Normal mouse fibroblasts expressing HBx were protected from death, whereas identical fibroblasts lacking the SEK1 component from the SAPK pathway succumbed to Fas-mediated apoptosis, whether HBx was present or not. Assays showed that caspase 3 and 8 activities and the release of cytochrome c from mitochondria were inhibited, in the presence of HBx, following stimulation with anti-Fas antibodies. Coprecipitation and confocal immunofluorescence microscopy experiments demonstrated that HBx localizes with a cytoplasmic complex containing MEKK1, SEK1, SAPK, and 14-3-3 proteins. Finally, mutational analysis of HBx demonstrated that a potential binding region for 14-3-3 proteins was essential for induction of SAPK/JNK activity and protection from Fas-mediated apoptosis. 相似文献
8.
Yo Morimoto Jun-ya Shibata Mizuki Takahata Omar Myint Masanori Kohda 《Journal of Ethology》2010,28(3):429-436
Like many other gobies, male Isaza (Gymnogobius isaza) which are endemic to Lake Biwa, Japan, exclusively care for broods in nests. This goby may have an optimal range of brood
size (i.e., an average clutch size of about 2000–3000 eggs) within which they may produce larger numbers of hatching young
because much larger broods may be destroyed by fungal infection before hatching. This optimal brood size hypothesis (Takahashi
et al. in J Ethol 22:153–159, 2004) predicts that (1) after spawning, both males and females will refuse additional spawning by other gravid females (second
females) to keep brood sizes within optimal ranges, (2) larger fish will repel second females more successfully than will
smaller fish, and thus, (3) both sexes prefer larger mates. To examine these predictions, we first observed Isaza’s aggressive
behaviors in aquaria and investigated whether fish attacked and repelled second females that were introduced after spawning,
and, if so, what were the sizes of fish that did so. Large fish, regardless of sex, aggressively prevented second females
from entering the nest, but second females larger than the pairs displaced the pair females forcibly and spawned eggs into
their clutches. Mate choice experiments showed that males preferred large females. Although females’ choice of large mates
was not confirmed, many results may largely coincide with the predictions of the optimal brood size hypothesis. Thus, Isaza
males’ choice of large mates will be advantageous for defending against brood parasitism by conspecific females and for achieving
optimal clutch size. 相似文献
9.
Gundi VA Kosoy MY Myint KS Shrestha SK Shrestha MP Pavlin JA Gibbons RV 《Applied and environmental microbiology》2010,76(24):8247-8254
Bartonellae were detected in a total of 152 (23.7%) of 642 tissues from 108 (48.4%) of 223 small mammals trapped in several urban areas of Nepal. Based on rpoB and gltA sequence analyses, genotypes belonging to seven known Bartonella species and five genotypes not belonging to previously known species were identified in these animals. 相似文献
10.
Myint Myint Khine Norbert Arnold Katrin Franke Andrea Porzel Jürgen Schmidt Ludger Wessjohann 《Biochemical Systematics and Ecology》2007
A new cardenolide, 17β-H-periplogenin-3-O-β-d-digitoxoside (1), and a new pregnane glycoside, Δ5-pregnene-3β,16α-diol-d-O-[2,4-O-diacetyl-β-digitalopyranosyl-(1 → 4)-β-d-cymaropyranoside]-16-O-[β-d-glucopyranoside] (2) were isolated from the roots of Streptocaulon tomentosum (Asclepiadaceae) together with a series of known compounds. Their chemotaxonomic significance for the separation of S. tomentosum from Streptocaulon juventas is discussed, suggesting a rather clear distinction of these species. 相似文献