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1.
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   
2.
The CAF1 protein is a component of the CCR4–NOT deadenylase complex. While yeast CAF1 displays deadenylase activity, this activity is not required for its deadenylation function in vivo, and CCR4 is the primary deadenylase in the complex. In order to identify CAF1-specific functional regions required for deadenylation in vivo, we targeted for mutagenesis six regions of CAF1 that are specifically conserved among CAF1 orthologs. Defects in residues 213–215, found to be a site required for binding CCR4, reduced the rate of deadenylation to a lesser extent and resulted in in vivo phenotypes that were less severe than did defects in other regions of CAF1 that displayed greater contact to CCR4. These results imply that CAF1, while affecting deadenylation through its contact to CCR4, has functions in deadenylation separate from its contact to CCR4. Synthetic lethalities of caf1Δ, but not that of ccr4Δ, with defects in DHH1 or PAB1, both of which are involved in translation, further supports a role of CAF1 separate from that of CCR4. Importantly, other mutations in PAB1 that reduced translation, while not affecting deadenylation by themselves or when combined with ccr4Δ, severely blocked deadenylation when coupled with a caf1 deletion. These results indicate that both CAF1 and factors involved in translation are required for deadenylation.  相似文献   
3.
Images of multiply labeled fluorescent samples provide unique insights into the localization of molecules, cells, and tissues. The ability to image multiple channels simultaneously at high speed without cross talk is limited to a few colors and requires dedicated multichannel or multispectral detection procedures. Simpler microscopes, in which each color is imaged sequentially, produce a much lower frame rate. Here, we describe a technique to image, at high frame rate, multiply labeled samples that have a repeating motion. We capture images in a single channel at a time over one full occurrence of the motion then repeat acquisition for other channels over subsequent occurrences. We finally build a high-speed multichannel image sequence by combining the images after applying a normalized mutual information-based time registration procedure. We show that this technique is amenable to image the beating heart of a double-labeled embryonic quail in three channels (brightfield, yellow, and mCherry fluorescent proteins) using a fluorescence wide-field microscope equipped with a single monochrome camera and without fast channel switching optics. We experimentally evaluate the accuracy of our method on image series from a two-channel confocal microscope.  相似文献   
4.
Serine/arginine-rich splicing factor 3 (SRSF3), a member of the serine/arginine (SR)-rich family of proteins, regulates both alternative splicing of pre-mRNA and export of mature mRNA from the nucleus. Although its role in nuclear mRNA processing is well understood, the mechanism by which it alters the fate of cytoplasmic mRNA molecules remains elusive. Here, we provide evidence that SRSF3 not only regulates the alternative splicing pattern of programmed cell death 4 (PDCD4) mRNA, but also modulates its translational efficiency in the cytoplasm by lowering translation levels. We observed a marked increase in PDCD4 mRNA in translating polysome fractions upon silencing of SRSF3, and, conversely, ectopic overexpression of SRSF3 shifted PDCD4 mRNA into non-translating ribosomal fractions. In live cells, SRSF3 colocalized with PDCD4 mRNA in P-bodies (PBs), where translationally silenced mRNAs are deposited, and this localization was abrogated upon SRSF3 silencing. Furthermore, using two different reporter systems, we showed that SRSF3 interacts directly with PDCD4 mRNA and mediates translational repression by binding to the 5′-untranslated region (5′-UTR). In summary, our data suggest that the oncogenic potential of SRSF3 might be realized, in part, through the translational repression of PDCD4 mRNA.  相似文献   
5.
6.
Maturity Onset Diabetes of Young (MODY) is a monogenic and autosomal dominant form of diabetes mellitus with onset of the disease often before 25 years of age. It is due to dysfunction of pancreatic ß cells characterised by non-ketotic diabetes and absence of pancreatic auto-antibodies. It is frequently mistaken for type 1 or type 2 diabetes mellitus. Diagnosis of MODY is important as the GCK subtype has better prognosis and may not require any treatment. Subtypes HNF1A and HNF4A are sensitive to sulfonylureas, however diabetes complications are common if not treated early. Moreover, there is genetic implication for the patient and family. Rare MODY subtypes can be associated with pancreatic and renal anomalies as well as exocrine dysfunction of the pancreas. So far there are six widely accepted subtypes of MODY described but the list has grown to nine. Although the majority of diabetes mellitus in youth remains type 1 and the incidence of type 2 is rising, MODY should be considered in patients with non-ketotic diabetes at presentation, and in patients with a strong family history of diabetes mellitus without pancreatic auto-antibodies. Furthermore the diagnosis must be confirmed by molecular studies. With advancement in genomic technology, rapid screening for MODY mutations will become readily available in the future.  相似文献   
7.
Banana is one of the most important subtropical crops. The genetic system, however, is relatively unknown and is complicated by specific interhybridization, heterozygosity, and polyploidy, which are common in most clones. These factors make identification of closely related banana cultivars difficult, particularly when sterile. Amplified fragment length polymorphism (AFLP) analysis using eight primer combinations was carried out on 16 banana cultivars. Results showed that AFLP could be used to distinguish the different cultivars by their unique banding patterns. Unique AFLP molecular markers were detected for 12 banana cultivars, which can be used to develop specific probes for identification purposes. The cluster analysis also revealed the need for a link between genotype studies using molecular techniques and the current system of classification of Musa cultivars based purely on morphological traits.  相似文献   
8.
The incidence of melanoma among the Asian population is lower compared to that among the Western European population. These populations differed in their most common histopathologic subtypes, acral lentiginous melanoma being the most common in the Asian population. Although the dermoscopic features of the melanomas on the acral skin have been thoroughly investigated in the Asian population, studies concerning the dermoscopic patterns of melanomas on the non-acral skin have been scarce. The aim of this study was to investigate the dermoscopic patterns of melanomas on the trunk and extremities in the Asian population. To achieve this, we evaluated the dermoscopic patterns of 22 primary melanomas diagnosed at two university hospitals in Korea. In addition, 100 benign melanocytic lesions were included as the control group for comparative analysis. A P value less than 0.05 was regarded as statistically significant. Melanoma-associated dermoscopic features such as asymmetry (odds ratio [OR], 30.00), multicolor pattern (OR, 30.12), blotches (OR, 13.50), blue white veils (OR, 15.75), atypical pigment networks (OR, 9.71), irregular peripheral streaks (OR, 6.30), atypical vascular patterns (OR, 11.50), ulcers (OR, 15.83), atypical dots/globules (OR, 3.15), shiny white lines (OR, 5.88), and regression structures (OR, 7.06) were more commonly observed in patients with melanomas than in patients of the control group. The mean dermoscopic scores obtained on the 7-point checklist, revised 7-point checklist, 3-point checklist, ABCD rule, and CASH algorithm were 5.36, 3.41, 2.05, 6.89, and 9.68, respectively, in the primary melanomas, and 1.33, 0.93, 0.46, 2.45, and 3.60, respectively, in the control group (all, P < 0.001). The present study showed that melanoma-related dermoscopic patterns were common in Asian patients. Dermoscopy is a reliable diagnostic tool for the melanomas of the trunk and extremities in the Asian populations.  相似文献   
9.
Several aquaporins (AQPs) have been identified to be present in the eyes, and it has been suggested that they are involved in the movement of water and small solutes. AQP6, which has low water permeability and transports mainly anions, was recently discovered in the eyes. In the present study, we investigate the localization of AQP6 in the rat retina and show that AQP6 is selectively localized to the ganglion cell layer and the outer plexiform layer. Along with the gradual decrease in retinal ganglion cells after a crushing injury of optic nerve, immunofluorescence signals of AQP6 gradually decreased. Confocal microscope images confirmed AQP6 expression in retinal ganglion cells and Müller cells in vitro. Therefore, AQP6 might participate in water and anion transport in these cells.  相似文献   
10.
Activation of neutrophils results in a one-electron reduction of oxygen to produce the superoxide anion and other oxygen-derived, microbicidal species. Evidence from many kinetic studies of oxygen-derived radicals generated by stimulated neutrophils in vitro shows that radical production is optimal at 37°C but only lasts several minutes and then rapidly subsides. These findings support the widely held perception that the neutrophil's “oxidative burst” is a transitory event that peaks within minutes of stimulation and ends shortly thereafter. However, while some studies have shown that under controlled conditions stimulated neutrophils can generate superoxide continuously for several hours, others have observed that the superoxide formation by neutrophils stimulated in buffer at 37°C does not persist. To reconcile the conflicting findings and to better understand neutrophil function, we have reinvestigated the effect of temperature on the kinetics of radical generation by PMA-stimulated cells. Electron paramagnetic resonance spectroscopy coupled with spin-trapping and SOD-inhibitable ferricytochrome c reduction were used to monitor superoxide production by neutrophils stimulated at either 25°C or 37°C in RPMI 1640 medium or in Hank's balanced salt solution. When oxygen was supplied continuously, neutrophils stimulated at 25°Cin buffer or in medium generated superoxide for several hours but at 37°C. particularly in HBSS, O2-formation strikingly and rapidly decreased. This cessation of superoxide generation was reversible by lowering the temperature back to 25°C. These data imply that in vivo neutrophils may be capable of generating oxy-radicals for prolonged periods. In part, our results may also explain the often observed termination of neutrophil-derived radical formation in vitro and help to dispel the perception that neutrophil-derived oxy-radical production is an ephemeral phenomenon.  相似文献   
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