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1.
We report the first application of a novel amino-Li resin to water-based solid-phase peptide synthesis (SPPS) applying the Smoc-protecting group approach. We demonstrated that it is a suitable support for the sustainable water-based alternative to a classical SPPS approach. The resin possesses good swelling properties in aqueous milieu, provides significant coupling sites, and may be applicable to the synthesis of difficult sequences and aggregation-prone peptides.  相似文献   
2.
Two morphological variants of Terminalia alata (Combretaceae) differed in leaf flushing phenology and spatial distribution in a Cambodian deciduous forest. The hairy‐type trees displayed leaf exchange behavior in the middle of the dry season. The glabrous type flushed new leaves 3 months after the wet season started. The leafless period of the hairy type was estimated to be <1 month, whereas that of the glabrous type lasted more than 5 months. The landscape‐scale leaf exchange behavior was similar to that of the hairy type. The two types showed clear spatial separation. The hairy type was limited to flat areas with deep soils. The dominance of the glabrous type in hilly areas with shallow soils suggests that it is adapted to water‐limited environments. The abundance of the glabrous type in hilly areas and its unique leaf phenology probably influence the carbon, energy and water balance at the landscape level.  相似文献   
3.
Potato mop-top virus (PMTV; genus Pomovirus; family Virgaviridae) is transmitted by the soil-borne Spongospora subterranea f.sp. subterranea, a protoctist that causes powdery scab on potato. PMTV is distributed widely in the potato growing areas in South and North America, Japan and northwestern Europe. This article reviews the current knowledge on detection, distribution and control of PMTV with focus on the Baltic Sea region. Since the 1980s, PMTV has caused great economic losses to potato production in the Nordic countries (Norway, Sweden, Denmark and Finland), but its occurrence in other countries of the Baltic Sea region remained unknown. To fill this knowledge gap, harmonised sampling and virus detection procedures including bioassays and serological and molecular methods were employed by 21 research institutions to detect PMTV in potato tubers and soil samples in 2005–2008. Potato growing areas were widely contaminated with PMTV in the Nordic countries. Only the main seed potato production area in northern Sweden and the High Grade seed potato production zone in Finland were negative for PMTV. Intensive and systematic surveys in Poland in 2004–2008 found no evidence of PMTV, except a single PMTV-infected tuber detected in 2008. Surveys in the Baltic countries (Lithuania, Latvia and Estonia) and northwestern Russia (Leningrad province) were negative for PMTV, except infection of minitubers in a screenhouse in Latvia in 2005. Varying percentages of tubers expressing spraing symptoms in Sweden, Norway, Denmark and Poland were infected with Tobacco rattle virus, and bioassays indicated similar results for Russia. Incidence of symptomless infections with PMTV was high in tubers of many potato cultivars. Here, we discuss the contrasting patterns of distribution of PMTV in the Baltic Sea region, factors playing a role in dispersal and establishment of PMTV in new fields and means for controlling PMTV and its spread to new areas. We emphasise the use of the current virus-specific methods for the detection of PMTV in symptomless potato tubers and the high risks of disseminating PMTV to new fields and areas in viruliferous resting spores of S. subterranea in the soil adhering to seed tubers. PMTV-resistant potato cultivars will provide the only sustainable means for preventing yield losses in the infested fields and the prospects of resistance breeding are summarised.  相似文献   
4.
We established a strategy for protein production and purification via expression in Yarrowia lipolytica as Lip2p fusion protein. To evaluate the expression system a cysteine-rich miniprotein, an antibody fragment and an enzyme showing galactose oxidase activity were chosen. These proteins have varying disulfide bond content, size, and structural complexity. Endogenous lipase Lip2p was used as a fusion partner to direct the fused proteins to the extracellular medium. A linker sequence was introduced at the junction of Lip2p and the respective fused protein that contains a hexahistidine tag followed by a TEV protease cleavage site. This allows for a specific and simple purification via IMAC for capturing the secreted proteins from the supernatant followed by a second IMAC for removing all contaminants after proteolytic release of the protein of interest. Up to 174 mg/L fusion protein was obtained using shake flask cultivation. Functionality of each of the purified proteins was confirmed by individual assays. Expression of proteins of interest via Lip2p fusion not only provides a convenient expression and purification scheme but also enables for an online monitoring of accumulation of secreted fusion proteins in the medium by exploiting the intrinsic lipase activity of the fusion.  相似文献   
5.
Knee osteoarthritis is a chronic, indolent disease that will affect an ever increasing number of patients, especially the elderly and the obese. It is characterized by degeneration of the cartilage substance inside the knee which leads to pain, stiffness and tenderness. By some estimations in 2030, only in the United States, this medical condition will burden 67 million people. While conventional treatments like physiotherapy or drugs offer temporary relief of clinical symptoms, restoration of normal cartilage function has been difficult to achieve. Moreover, in severe cases of knee osteoarthritis total knee replacement may be required. Total knee replacements come together with high effort and costs and are not always successful. The aim of this review is to outline the latest advances in stem cell therapy for knee osteoarthritis as well as highlight some of the advantages of stem cell therapy over traditional approaches aimed at restoration of cartilage function in the knee. In addition to the latest advances in the field, challenges associated with stem cell therapy regarding knee cartilage regeneration and chondrogenesis in vitro and in vivo are also outlined and analyzed. Furthermore, based on their critical assessment of the present academic literature the authors of this review share their vision about the future of stem cell applications in the treatment of knee osteoarthritis.  相似文献   
6.
Neglected and Underutilized Crop Species (NUS) are grown primarily by traditional farmers in developing countries. They were once more widely grown but are today falling into disuse for a variety of agronomic, genetic, economic and cultural factors. While these crops continue to be maintained by socio-cultural preferences and use practices, most of them remain inadequately characterized and neglected by research and conservation. The aim of our work was to improve the agricultural portfolio by identifying promising neglected and underutilised species in China, Cambodia, Northeastern Thailand and Northern Vietnam. We began with preparing a “Masterlist” containing 260 species, based on farmer interviews and literature review. After an initial pre-selection we identified 17 NUS for China, 13 for Cambodia, 12 for Thailand, and 22 for Vietnam as of highest priority. These NUS then underwent a multi-criteria and trans-disciplinary assessment involving 511 stakeholders such as scientists, farmers, NGOs and policy makers. Based on the assessment we identified the most promising NUS for each country. We also identified some limitations for the promotion of so-called priority NUS regarding to some substancial disagreement between the involved stakeholders. In China and Cambodia, for example, farmers judged the potential of NUS significantly lower than other stakeholders, and in Vietnam scientists and policy makers had substantially different opinions on NUS compared to farmers. Addressing these ambiguous views will be highly relevant to the develoment of an improved agricultural portfolio.
Markus SchmidtEmail: Email:
  相似文献   
7.
The regulation of cell morphology is a dynamic process under the control of multiple protein complexes acting in a coordinated manner. Phosphoinositide 3-kinases (PI3K) and their lipid products are widely involved in cytoskeletal regulation by interacting with proteins regulating RhoGTPases. Class II PI3K isoforms have been implicated in the regulation of the actin cytoskeleton, although their exact role and mechanism of action remain to be established. In this report, we have identified Dbl, a Rho family guanine nucleotide exchange factor (RhoGEF) as an interaction partner of PI3KC2β. Dbl was co-immunoprecipitated with PI3KC2β in NIH3T3 cells and cancer cell lines. Over-expression of Class II phosphoinositide 3-kinase PI3KC2β in NIH3T3 fibroblasts led to increased stress fibres formation and cell spreading. Accordingly, we found high basal RhoA activity and increased serum response factor (SRF) activation downstream of RhoA upon serum stimulation. In contrast, the dominant-negative form of PI3KC2β strongly reduced cell spreading and stress fibres formation, as well as SRF response. Platelet-derived growth factor (PDGF) stimulation of wild-type PI3KC2β over-expressing NIH3T3 cells strongly increased Rac and c-Jun N-terminal kinase (JNK) activation, but failed to show similar effect in the cells with the dominant-negative enzyme. Interestingly, epidermal growth factor (EGF) and PDGF stimulation led to increased extracellular signal-regulated kinase (Erk) and Akt pathway activation in cells with elevated wild-type PI3KC2β expression. Furthermore, increased expression of PI3KC2β protected NIH3T3 from detachment-dependent death (anoikis) in a RhoA-dependent manner. Taken together, these findings suggest that PI3KC2β modulates the cell morphology and survival through a specific interaction with Dbl and the activation of RhoA.  相似文献   
8.
Applied Microbiology and Biotechnology - Flavour and fragrance compounds are extremely important for food, feed, cosmetic and pharmaceutical industries. In the last decades, due to the...  相似文献   
9.
Recent studies have shown that Plasmodium falciparum malaria parasites in Pailin province, along the border between Thailand and Cambodia, have become resistant to artemisinin derivatives. To better define the epidemiology of P. falciparum populations and to assess the risk of the possible spread of these parasites outside Pailin, a new epidemiological tool named “Focused Screening and Treatment” (FSAT), based on active molecular detection of asymptomatic parasite carriers was introduced in 2010. Cross-sectional malariometric surveys using PCR were carried out in 20 out of 109 villages in Pailin province. Individuals detected as P. falciparum carriers were treated with atovaquone-proguanil combination plus a single dose of primaquine if the patient was non-G6PD deficient. Interviews were conducted to elicit history of cross-border travel that might contribute to the spread of artemisinin-resistant parasites. After directly observed treatment, patients were followed up and re-examined on day 7 and day 28. Among 6931 individuals screened, prevalence of P. falciparum carriers was less than 1%, of whom 96% were asymptomatic. Only 1.6% of the individuals had a travel history or plans to go outside Cambodia, with none of those tested being positive for P. falciparum. Retrospective analysis, using 2010 routine surveillance data, showed significant differences in the prevalence of asymptomatic carriers discovered by FSAT between villages classified as “high risk” and “low risk” based on malaria incidence data. All positive individuals treated and followed-up until day 28 were cured. No mutant-type allele related to atovaquone resistance was found. FSAT is a potentially useful tool to detect, treat and track clusters of asymptomatic carriers of P. falciparum along with providing valuable epidemiological information regarding cross-border movements of potential malaria parasite carriers and parasite gene flow.  相似文献   
10.

Background

Body mass index (BMI) and waist circumference (WC) are used in risk assessment for the development of non-communicable diseases (NCDs) worldwide. Within a Cambodian population, this study aimed to identify an appropriate BMI and WC cutoff to capture those individuals that are overweight and have an elevated risk of vascular disease.

Methodology/Principal Findings

We used nationally representative cross-sectional data from the STEP survey conducted by the Department of Preventive Medicine, Ministry of Health, Cambodia in 2010. In total, 5,015 subjects between age 25 and 64 years were included in the analyses. Chi-square, Fisher’s Exact test and Student t-test, and multiple logistic regression were performed. Of total, 35.6% (n = 1,786) were men, and 64.4% (n = 3,229) were women. Mean age was 43.0 years (SD = 11.2 years) and 43.6 years (SD = 10.9 years) for men and women, respectively. Significant association of subjects with hypertension and hypercholesterolemia was found in those with BMI ≥23.0 kg/m2 and with WC >80.0 cm in both sexes. The Area Under the Curve (AUC) from Receiver Operating Characteristic curves was significantly greater in both sexes (all p-values <0.001) when BMI of 23.0 kg/m2 was used as the cutoff point for overweight compared to that using WHO BMI classification for overweight (BMI ≥25.0 kg/m2) for detecting the three cardiovascular risk factors. Similarly, AUC was also significantly higher in men (p-value <0.001) when using WC of 80.0 cm as the cutoff point for central obesity compared to that recommended by WHO (WC ≥94.0 cm in men).

Conclusion

Lower cutoffs for BMI and WC should be used to identify of risks of hypertension, diabetes, and hypercholesterolemia for Cambodian aged between 25 and 64 years.  相似文献   
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