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91.
Verena Ilona Carrara Julien Zwang Elizabeth A. Ashley Ric N. Price Kasia Stepniewska Marion Barends Alan Brockman Tim Anderson Rose McGready Lucy Phaiphun Stephane Proux Michele van Vugt Robert Hutagalung Khin Maung Lwin Aung Pyae Phyo Piyanuch Preechapornkul Mallika Imwong Sasithon Pukrittayakamee Pratap Singhasivanon Nicholas J. White Fran?ois Nosten 《PloS one》2009,4(2)
Background
Artemisinin combination treatments (ACT) are recommended as first line treatment for falciparum malaria throughout the malaria affected world. We reviewed the efficacy of a 3-day regimen of mefloquine and artesunate regimen (MAS3), over a 13 year period of continuous deployment as first-line treatment in camps for displaced persons and in clinics for migrant population along the Thai-Myanmar border.Methods and Findings
3,264 patients were enrolled in prospective treatment trials between 1995 and 2007 and treated with MAS3. The proportion of patients with parasitaemia persisting on day-2 increased significantly from 4.5% before 2001 to 21.9% since 2002 (p<0.001). Delayed parasite clearance was associated with increased risk of developing gametocytaemia (AOR = 2.29; 95% CI, 2.00–2.69, p = 0.002). Gametocytaemia on admission and carriage also increased over the years (p = 0.001, test for trend, for both). MAS3 efficacy has declined slightly but significantly (Hazards ratio 1.13; 95% CI, 1.07–1.19, p<0.001), although efficacy in 2007 remained well within acceptable limits: 96.5% (95% CI, 91.0–98.7). The in vitro susceptibility of P. falciparum to artesunate increased significantly until 2002, but thereafter declined to levels close to those of 13 years ago (geometric mean in 2007: 4.2 nM/l; 95% CI, 3.2–5.5). The proportion of infections caused by parasites with increased pfmdr1 copy number rose from 30% (12/40) in 1996 to 53% (24/45) in 2006 (p = 0.012, test for trend).Conclusion
Artesunate-mefloquine remains a highly efficacious antimalarial treatment in this area despite 13 years of widespread intense deployment, but there is evidence of a modest increase in resistance. Of particular concern is the slowing of parasitological response to artesunate and the associated increase in gametocyte carriage. 相似文献92.
Antony J. Lynam Alan Rabinowitz Than Myint Myint Maung Kyaw T. Latt Saw Htoo T. Po 《Population Ecology》2009,51(1):115-121
As part of a national strategy for recovering tiger populations, the Myanmar Government recently proposed its first and the
world’s largest tiger reserve in the Hukaung Valley, Kachin State. During November 2002–June 2004, camera-traps were used
to record tigers, identify individuals, and, using capture–recapture approaches, estimate density in the reserve. Despite
extensive (203 trap locations, 275–558 km2 sample plots) and intensive (>4,500 trap nights, 9 months of sampling) survey efforts, only 12 independent detections of
six individual tigers were made across three study sites. Due to the sparse data, estimates of tiger abundance generated by
Program CAPTURE could not be made for all survey sites. Other approaches to estimating density, based on numbers of tigers
caught, or derived from borrowed estimates of detection probability, offer an alternative to capture–recapture analysis. Tiger
densities fall in the range of 0.2–2.2 tigers/100 km2, with 7–71 tigers inside a 3,250 km2 area of prime tiger habitat, where efforts to protect tigers are currently focused. Tiger numbers might be stabilized if
strict measures are taken to protect tigers and their prey from seasonal hunting and to suppress illegal trade in wildlife.
Efforts to monitor abundance trends in the tiger population will be expensive given the difficulty with which tiger data can
be obtained and the lack of available surrogate indices of tiger density. Monitoring occupancy patterns, the subject of a
separate ongoing study, may be more efficient. 相似文献
93.
Takeshi Shimogiri George Msalya Si Lhyam Myint Shin Okamoto Kotaro Kawabe Kazuaki Tanaka Hideyuki Mannen Mitsuru Minezawa Takao Namikawa Takashi Amano Yoshio Yamamoto Yoshizane Maeda 《Biochemical genetics》2010,48(9-10):829-839
Six polymorphic sites of the bovine prion protein gene (PRNP) were genotyped in 569 animals of Asian native cattle, Japanese breeds, purebred mythun (Bos frontalis), and mythun × cattle composite animals. At the 23-bp indel site, a deletion (23?) allele was a major allele in all populations except mythun. At the 12-bp indel site, an insertion (12+) allele was a major allele in all populations. The 14-bp indel site was polymorphic in all Asian native cattle. In the octapeptide repeat region, a six-repeat allele was a major allele in all populations, and 5/5 and 4/6 genotypes were detected in Japanese Black and Mongolian cattle and in mythun, respectively. Two nonsynonymous single nucleotide polymorphisms (SNPs) (K3T and S154N) were detected in Asian native cattle and mythun. Haplotype analysis using the genotypes of the six sites estimated 33 different haplotypes. The haplotype 23? 12? K 6 S 14+ was found in all populations. 相似文献
94.
95.
L. H. Aung 《Biologia Plantarum》1986,28(6):407-411
The action of two anticytokinins, 3-methyl-7-n-pentyl-aminopyrazolo[4,3-d] pyrimidine and 4-cyclopentylamino-2-methylthiopyrrolo [2,3-d] pyrimidine on the zeatin and 6-benzylaminopurine induced lateral bud growth ofLycopersicon esculentum Mill. cv. Fireball seedlings was studied. Bud growth stimulation by 0.1 mM zeatin was not overcome by application of anticytokinin
at concentrations of 0.01 to 1.0 μ 24-h after zeatin application. However, application of 0.1 μM of anticytokinin 24-h before
0.1 mM zeatin caused a significant enhancement of bud growth. A simultaneous application of 1 mM anticytokinin and 6-benzylaminopurine
or concurrent with young leaves excision significantly reduced bud growth. 相似文献
96.
Induction of tyrosine aminotransferase in isolated liver cells 总被引:1,自引:0,他引:1
97.
John W. Huffman John Liddle Shu Yu Mie Mie Aung Mary E. Abood Jenny L. Wiley Billy R. Martin 《Bioorganic & medicinal chemistry》1999,7(12):964
The synthesis and pharmacology of 15 1-deoxy-Δ8-THC analogues, several of which have high affinity for the CB2 receptor, are described. The deoxy cannabinoids include 1-deoxy-11-hydroxy-Δ8-THC (5), 1-deoxy-Δ8-THC (6), 1-deoxy-3-butyl-Δ8-THC (7), 1-deoxy-3-hexyl-Δ8-THC (8) and a series of 3-(1′,1′-dimethylalkyl)-1-deoxy-Δ8-THC analogues (2, n=0–4, 6, 7, where n=the number of carbon atoms in the side chain−2). Three derivatives (17–19) of deoxynabilone (16) were also prepared. The affinities of each compound for the CB1 and CB2 receptors were determined employing previously described procedures. Five of the 3-(1′,1′-dimethylalkyl)-1-deoxy-Δ8-THC analogues (2, n=1–5) have high affinity (Ki=<20 nM) for the CB2 receptor. Four of them (2, n=1–4) also have little affinity for the CB1 receptor (Ki=>295 nM). 3-(1′,1′-Dimethylbutyl)-1-deoxy-Δ8-THC (2, n=2) has very high affinity for the CB2 receptor (Ki=3.4±1.0 nM) and little affinity for the CB1 receptor (Ki=677±132 nM).
Scheme 3. (a) (C6H5)3PCH3+ Br−, n-BuLi/THF, 65°C; (b) LiAlH4/THF, 25°C; (c) KBH(sec-Bu)3/THF, −78 to 25°C then H2O2/NaOH. 相似文献
98.
Miller CS Johnson DH Schroeter JP Myint L Glantz RM 《Journal of computational neuroscience》2003,15(2):247-269
Motoneuron responses were elicited by global visual motion and stepwise displacements of an illuminated stripe. Stimulus protocols were identical to those used in previous behavioral studies of compensatory eyestalk reflexes. The firing rates and directional selectivity of the motoneuron responses were measured with respect to four stimulus dimensions (spatial frequency, contrast, angular displacement and velocity). The directional selectivity of the motoneuron response was correlated to the previously measured gain of the reflex for each stimulus dimension. The information theoretical analysis is based upon Kullback-Leibler (K-L) distances which measure the dissimilarity of responses to different stimuli. K-L distances for single neurons are strongly influenced by the mean rate difference of the responses to any pair of stimuli. Because of redundancy, the joint K-L distances of pairs of neurons were less than the sum of the K-L distances of the individual neurons. Furthermore, the joint K-L distances were only weakly influenced by correlations among coactivated neurons. For most of the stimulus dimensions, the K-L distances of single motoneurons were not sufficient to account for the stimulus discriminations exhibited by the eyestalk reflex which typically required the summed output of 2 to 5 motoneurons. Thus the behaviorally relevant information is encoded in the motoneuron ensemble. The minimum time required to discriminate the direction of motion (the encoding window) for a single motoneuron is about 380 to 480 ms (including a 175 ms response latency) for stepwise displacements and up to 1.0 s for global motion. During this period a motoneuron fires 2 to 3 impulses. 相似文献
99.
Effects of endothelin on microcirculation of the pancreas. 总被引:11,自引:0,他引:11
K Takaori K Inoue M Kogire S Higashide T Tun T Aung R Doi N Fujii T Tobe 《Life sciences》1992,51(8):615-622
Endothelin, a newly described endothelial-derived peptide, has potent vasoconstrictive properties and has been speculated to play a physiological role in the regulation of blood flow in some organs. The present study was designed to evaluate the effects of endothelin-1, endothelin-2 and endothelin-3 on the pancreatic microcirculation. Pancreatic tissue blood flow was measured by a laser Doppler flow meter in anesthetized dogs and endothelin-1, endothelin-2 or endothelin-3 was injected intravenously in graduated doses. Endothelins induced dose-dependent decreases in pancreatic tissue blood flow. Endothelin-1, endothelin-2 and endothelin-3 at a dose of 100 pmol/kg reduced pancreatic blood flow by 45.4%, 19.6% and 51.9%, respectively, whereas systemic arterial blood pressure was not significantly affected. When endothelin-3 was administered at a dose of 1000 pmol/kg, pancreatic blood flow was decreased by 73.5% with a concomitant increase of systemic arterial blood pressure by 17.6%. Endothelins potently decreased pancreatic tissue blood flow, suggesting a possible role of these agents in regulating the pancreatic microcirculation. 相似文献
100.
Interleukin-4 Diminishes CD8+ Respiratory Syncytial Virus-Specific Cytotoxic T-Lymphocyte Activity In Vivo
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Although interleukin-4 (IL-4) has been implicated in respiratory syncytial virus (RSV)-enhanced disease, the mechanism by which it modulates immune responses to primary RSV infection remains unclear. We have developed a system to investigate the effect of IL-4 on RSV epitope-specific cytotoxic T-lymphocyte (CTL) effector function in vivo, using an H-2K(d)-restricted RSV M2 epitope. BALB/c mice were infected with recombinant vaccinia virus (rVV) constructed to express RSV M2 protein (vvM2) alone or coexpress M2 and IL-4 (vvM2/IL-4). Splenocytes were assessed for M2-specific CTL activity in a direct (51)Cr release assay and intracellular gamma interferon (IFN-gamma) production by fluorescence-activated cell sorting analysis. Mice infected with vvM2/IL-4 had less M2-specific primary CTL activity than those infected with vvM2. M2-specific CTL frequency, as measured by M2 peptide-induced intracellular IFN-gamma production, was diminished in the vvM2/IL-4 group, partially accounting for the reduction of CTL activity. Mice immunized with either construct were challenged intravenously with RSV 4 weeks postimmunization, and direct CTL were measured. These results demonstrate that local expression of IL-4, at the time of antigen presentation, diminishes the cytolytic activity of primary and memory CD8(+) RSV-specific CTL responses in vivo. 相似文献