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91.
To improve biocontrol of the cassava green mite, Mononychellus tanajoa, a series of screenhouse experiments were conducted on cassava to determine the effects of single and combined releases of the predatory mite Typhlodromalus aripo and the entomopathogenic fungus Neozygites tanajoae on the suppression of M. tanajoa. We showed that, separately or in combination, T. aripo and N. tanajoae significantly reduced M. tanajoa populations. Moreover, combined release of T. aripo and N. tanajoae on the same cassava plants improved M. tanajoa control. However, our data suggest between T. aripo and N. tanajoae an asymmetric competition that significantly affected N. tanajoae only. This interference is indirect, probably mediated by their common prey or host mite, M. tanajoa since N. tanajoae is not pathogenic to T. aripo. We conclude that adding N. tanajoae to T. aripo populations in Africa would not negatively affect T. aripo and would further promote biocontrol of M. tanajoa.  相似文献   
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Background aimsAn accurate and reliable assessment of bone marrow engraftment (BME) after hematopoietic stem cell transplantation (HSCT) is based on the ability to distinguish between recipient and donor cells at selected polymorphic short tandem repeat (STR) DNA loci. Buccal cells are an important source of DNA for determining the recipient's constitutional genotype, particularly in patients transplanted before the STR evaluation.MethodsGenomic DNA was extracted from the recipient buccal cells and from isolated CD3+ (T-cell lymphocyte) and CD33+ (myelocyte) cells after HSCT. BME analysis was performed using a STR-based polymerase chain reaction amplification method followed by fragment-size analysis for assessing the recipient-derived or donor-derived composition of cell lineage-specific peripheral blood DNA.ResultsWe identified three cases of complete buccal epithelial cell engraftment after HSCT detected by BME analysis, potentially leading to misinterpretation of testing results if these cells were used as the sole source for determining the recipient's genotype.ConclusionsThese cases suggest that complete engraftment of buccal epithelial cells may be a common finding in patients receiving HSCT, drawing attention to important issues such as the type of samples used for determining a patient's constitutional genotype that may confound testing results. This study also highlights the need for careful interpretation of the BME testing results in the context of the clinical findings.  相似文献   
93.

Background

Severe stress experienced in early life may have long-term effects on adult physiological and psychological health and well-being. We studied physical and psychosocial functioning in late adulthood in subjects separated temporarily from their parents in childhood during World War II.

Methods

The 1803 participants belong to the Helsinki Birth Cohort Study, born 1934–44. Of them, 267 (14.8%) had been evacuated abroad in childhood during WWII and the remaining subjects served as controls. Physical and psychosocial functioning was assessed with the Short Form 36 scale (SF-36) between 2001 and 2004. A test for trends was based on linear regression. All analyses were adjusted for age at clinical examination, social class in childhood and adulthood, smoking, alcohol intake, physical activity, body mass index, cardiovascular disease and diabetes.

Results

Physical functioning in late adulthood was lower among the separated men compared to non-separated men (b = −0.40, 95% confidence interval [95% CI]: −0.71 to −0.08). Those men separated in school age (>7 years) and who were separated for a duration over 2 years had the highest risk for lower physical functioning (b = −0.89, 95% CI: −1.58 to −0.20) and (b = −0.65, 95% CI: −1.25 to −0.05), respectively). Men separated for a duration over 2 years also had lower psychosocial functioning (b = −0.70, 95% CI: −1.35 to −0.06). These differences in physical and psychosocial functioning were not observed among women.

Conclusion

Early life stress may increase the risk for impaired physical functioning in late adulthood among men. Timing and duration of the separation influenced the physical and psychosocial functioning in late adulthood.  相似文献   
94.
A novel NAD(P) reductase like protein (RL) belonging to a class of reductases involved in phenylpropanoid synthesis was previously purified to homogeneity from the Sauromatum guttatum appendix. The Sauromatum appendix raises its temperature above ambient temperature to ~30 °C on the day of inflorescence opening (D-day). Changes in the charge state distribution of the protein in electrospray ionization–mass spectrometry spectra were observed during the development of the appendix. RL adopted two conformations, state A (an extended state) that appeared before heat-production (D ? 4 to D ? 2), and state B (a compact state) that began appearing on D ? 1 and reached a maximum on D-day. RL in healthy leaves of Arabidopsis is present in state A, whereas in thermogenic sporophylls of male cones of Encephalartos ferox is present in state B. These conformational changes strongly suggest an involvement of RL in heat-production. The biophysical properties of this protein are remarkable. It is self-assembled in aqueous solutions into micrometer sizes of organized morphologies. The assembly produces a broad range of cyclic and linear morphologies that resemble micelles, rods, lamellar micelles, as well as vesicles. The assemblies could also form network structures. RL molecules entangle with each other and formed branched, interconnected networks. These unusual assemblies suggest that RL is an oligomer, and its oligomerization can provide additional information needed for thermoregulation. We hypothesize that state A controls the plant basal temperature and state B allows a shift in the temperature set point to above ambient temperature.  相似文献   
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To assess presence of virus DNA in skin lesions, swab samples from 82 squamous cell carcinomas of the skin (SCCs), 60 actinic keratoses (AKs), paraffin-embedded biopsies from 28 SCCs and 72 kerathoacanthomas (KAs) and fresh-frozen biopsies from 92 KAs, 85 SCCs and 92 AKs were analyzed by high throughput sequencing (HTS) using 454 or Ion Torrent technology. We found total of 4,284 viral reads, out of which 4,168 were Human Papillomavirus (HPV)-related, belonging to 15 known (HPV8, HPV12, HPV20, HPV36, HPV38, HPV45, HPV57, HPV59, HPV104, HPV105, HPV107, HPV109, HPV124, HPV138, HPV147), four previously described putative (HPV 915 F 06 007 FD1, FA73, FA101, SE42) and two putatively new HPV types (SE46, SE47). SE42 was cloned, sequenced, designated as HPV155 and found to have 76% similarity to the most closely related known HPV type. In conclusion, an unbiased approach for viral DNA detection in skin tumors has found that, although some new putative HPVs were found, known HPV types constituted most of the viral DNA.  相似文献   
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Multinucleate cells play an important role in higher plants, especially during reproduction; however, the configurations of their cytoskeletons, which are formed as a result of mitosis without cytokinesis, have mainly been studied in coenocytes. Previous authors have proposed that in spite of their developmental origin (cell fusion or mitosis without cytokinesis), in multinucleate plant cells, radiating microtubules determine the regular spacing of individual nuclei. However, with the exception of specific syncytia induced by parasitic nematodes, there is no information about the microtubular cytoskeleton in plant heterokaryotic syncytia, i.e. when the nuclei of fused cells come from different cell pools. In this paper, we describe the arrangement of microtubules in the endosperm and special endosperm–placenta syncytia in two Utricularia species. These syncytia arise from different progenitor cells, i.e. cells of the maternal sporophytic nutritive tissue and the micropylar endosperm haustorium (both maternal and paternal genetic material). The development of the endosperm in the two species studied was very similar. We describe microtubule configurations in the three functional endosperm domains: the micropylar syncytium, the endosperm proper and the chalazal haustorium. In contrast to plant syncytia that are induced by parasitic nematodes, the syncytia of Utricularia had an extensive microtubular network. Within each syncytium, two giant nuclei, coming from endosperm cells, were surrounded by a three-dimensional cage of microtubules, which formed a huge cytoplasmic domain. At the periphery of the syncytium, where new protoplasts of the nutritive cells join the syncytium, the microtubules formed a network which surrounded small nuclei from nutritive tissue cells and were also distributed through the cytoplasm. Thus, in the Utricularia syncytium, there were different sized cytoplasmic domains, whose architecture depended on the source and size of the nuclei. The endosperm proper was isolated from maternal (ovule) tissues by a cuticle layer, so the syncytium and chalazal haustorium were the only way for nutrients to be transported from the maternal tissue towards the developing embryo.  相似文献   
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