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101.
Eighteen isolates if anaerobic coryneforms from human bone marrow and skin and four type strains of Propionibacterium were studied chemically, biochemically and antigenically. All of the isolates were identified as Propionibacterium acnes; of the 18 isolates,16 belonged to sterotype I and two to serotype II. By means of gas liquid chromatography and mass spectral analysis, a large amount of iso-type fatty acids, such as iso-pentadecanoic and iso-heptadecanoic acids were detected in whole cells of isolates and type strains. Antitumor and adjuvant effects of the isolates and type strains were found to differ considerably among the strains. One of the isolates, P. acnes C-7, which showed potent biological activities was fractionated by hot phenol-water extraction. The resulting insoluble middle layer was found the most effective in tumor protection, adjuvant action in immune response and phagocytic activity in mice.  相似文献   
102.
It is known that interfaces have various impacts on crystallization from a solution. Here, we describe crystallization of acetaminophen using a microflow channel, in which two liquids meet and form a liquid–liquid interface due to laminar flow, resulting in uniform mixing of solvents on the molecular scale. In the anti‐solvent method, the microflow mixing promoted the crystallization more than bulk mixing. Furthermore, increased flow rate encouraged crystal formation, and a metastable form appeared under a certain flow condition. This means that interface management by the microchannel could be a beneficial tool for crystallization and polymorph control.  相似文献   
103.
Hybridization between divergent lineages generates new allelic combinations. One mechanism that can hinder the formation of hybrid populations is mitonuclear incompatibility, that is, dysfunctional interactions between proteins encoded in the nuclear and mitochondrial genomes (mitogenomes) of diverged lineages. Theoretically, selective pressure due to mitonuclear incompatibility can affect genotypes in a hybrid population in which nuclear genomes and mitogenomes from divergent lineages admix. To directly and thoroughly observe this key process, we de novo sequenced the 747‐Mb genome of the coastal goby, Chaenogobius annularis, and investigated its integrative genomic phylogeographics using RNA‐sequencing, RAD‐sequencing, genome resequencing, whole mitogenome sequencing, amplicon sequencing, and small RNA‐sequencing. Chaenogobius annularis populations have been geographically separated into Pacific Ocean (PO) and Sea of Japan (SJ) lineages by past isolation events around the Japanese archipelago. Despite the divergence history and potential mitonuclear incompatibility between these lineages, the mitogenomes of the PO and SJ lineages have coexisted for generations in a hybrid population on the Sanriku Coast. Our analyses revealed accumulation of nonsynonymous substitutions in the PO‐lineage mitogenomes, including two convergent substitutions, as well as signals of mitochondrial lineage‐specific selection on mitochondria‐related nuclear genes. Finally, our data implied that a microRNA gene was involved in resolving mitonuclear incompatibility. Our integrative genomic phylogeographic approach revealed that mitonuclear incompatibility can affect genome evolution in a natural hybrid population.  相似文献   
104.

Herbaceous plant diversity including rare aquatic species has been lost in many countries by agricultural intensification and abandonment. In paddy fields of the Lao People’s Democratic Republic (Lao PDR), irrigation facilities have been constructed rapidly since 1997. The aim of this study was to clarify the impacts of double rice cropping accompanied by the introduction of irrigation systems on herbaceous plant diversity and utilization in paddy fields of southern Lao PDR. Ground vegetation surveys and interviews were conducted in Kok Deau and Lak 30 villages in Champasak Province, and propagule bank survey was conducted in Kok Deau village. The species richness and species diversity, measured by the Shannon’s diversity index, were not significantly different between the irrigated and rainfed paddies (p?>?0.05), when compared in both the wet and dry seasons. However, double rice cropping with irrigation systems affected herbaceous plant species composition in paddy fields. Increased use of chemical fertilizers in irrigated paddies resulted in predominance of tall undesirable species, such as Fimbristylis miliacea (L.) Vahl and Echinochloa colona (L.) Link. Small and frequently submerged species were dominant in the ground vegetation and propagule banks of the rainfed paddies. Since small submerged species are often sensitive to environmental changes, increase of irrigated paddy area may lead to a decrease in the variety of aquatic herbaceous plants in Lao PDR. While a total of 9 herbaceous plant species were utilized as foods in the villages, no change was recognized by farmers in species composition and frequency of utilization of paddy plants as food before and after the development of the irrigation systems.

  相似文献   
105.
Landscape and Ecological Engineering - This study investigated the export of dissolved iron (DFe) from river catchments with emphasis on land use and land cover (LULC). The DFe concentrations were...  相似文献   
106.
To understand the geographical differences between diapause systems and synchronization of adult occurrence in the soybean pod borer Leguminivora glycinivorella (Lepidoptera: Tortricidae), we examined the timing of winter diapause termination and intensity of summer diapause using univoltine and potentially bivoltine individuals in Iwate, Japan. In laboratory rearing experiments of mature larvae maintained at constant temperature (20 °C), winter diapause intensity weakened by January without photoperiodic responses. Meanwhile, summer diapause was maintained by the long day length and presumably terminated with the photoperiodic transition from long to short day length. The intensity of summer diapause was stronger for cocoons that transitioned from a 16 h light to 8 h dark (LD 16:8) to a LD 15:9 photoperiod than for those that transitioned from LD 15:9 to LD 14:10. These results suggest that populations distributed in relatively low-latitude areas, with partly or potentially bivoltine individuals, would have a weaker summer diapause or none at all. Moreover, sexual differences in the number of days to emergence were not detected when individuals experienced a photoperiodic transition from long to short day length, suggesting that the summer diapause system may function to synchronize the emergence of males and females in the population examined.  相似文献   
107.
Osmotic adjustment plays a fundamental role in water stress responses and growth in plants; however, the molecular mechanisms governing this process are not fully understood. Here, we demonstrated that the KUP potassium transporter family plays important roles in this process, under the control of abscisic acid (ABA) and auxin. We generated Arabidopsis thaliana multiple mutants for K+ uptake transporter 6 (KUP6), KUP8, KUP2/SHORT HYPOCOTYL3, and an ABA-responsive potassium efflux channel, guard cell outward rectifying K+ channel (GORK). The triple mutants, kup268 and kup68 gork, exhibited enhanced cell expansion, suggesting that these KUPs negatively regulate turgor-dependent growth. Potassium uptake experiments using 86radioactive rubidium ion (86Rb+) in the mutants indicated that these KUPs might be involved in potassium efflux in Arabidopsis roots. The mutants showed increased auxin responses and decreased sensitivity to an auxin inhibitor (1-N-naphthylphthalamic acid) and ABA in lateral root growth. During water deficit stress, kup68 gork impaired ABA-mediated stomatal closing, and kup268 and kup68 gork decreased survival of drought stress. The protein kinase SNF1-related protein kinases 2E (SRK2E), a key component of ABA signaling, interacted with and phosphorylated KUP6, suggesting that KUP functions are regulated directly via an ABA signaling complex. We propose that the KUP6 subfamily transporters act as key factors in osmotic adjustment by balancing potassium homeostasis in cell growth and drought stress responses.  相似文献   
108.
Abstract

The 5-oxo-6-methylene-pyrimidine-2,4-dione intermediate (6) that is formed when 5-acetoxy-6-acetoxymethyl-1-β-D-(5-O-acetyl-2,3-O-isopropylidene)-ribofuranosyluracil (5) is treated with sodium hydroxide undergoes cyclization at pH 14 to give 2′,3′-O-isopropylidene-5-hydroxy- O 5, 6-methanouridine (8) in good yield. Conversion of 8 into the 5-triflate ester 14 followed by reduction with [(Ph)3P]4Pd/Bu3SnH and deblocking with acetic acid then affords O 5′, 6-methanouridine (4) Conformational studies (NOE difference spectra, vicinal 1H-13C coupling constants, NOESY and CD spectra, molecular modeling) indicate that the C7-methylene group of 4 projects towards the furanose ring oxygen atom, producing a glycosyl rotation angle of about ? 160°.  相似文献   
109.
MCP-1/CCL2 plays an important role in the initiation and progression of cancer. Since tumor cells produce MCP-1, they are considered to be the main source of this chemokine. Here, we examined whether MCP-1 produced by non-tumor cells affects the growth and lung metastasis of 4T1 breast cancer cells by transplanting them into the mammary pad of WT or MCP-1−/− mice. Primary tumors at the injected site grew similarly in both mice; however, lung metastases were markedly reduced in MCP-1−/− mice, with significantly longer mouse survival. High levels of MCP-1 mRNA were detected in tumors growing in WT, but not MCP-1−/− mice. Serum MCP-1 levels were increased in tumor-bearing WT, but not MCP-1−/− mice. Transplantation of MCP-1−/− bone marrow cells into WT mice did not alter the incidence of lung metastasis, whereas transplantation of WT bone marrow cells into MCP-1−/− mice increased lung metastasis. The primary tumors of MCP-1−/− mice consistently developed necrosis earlier than those of WT mice and showed decreased infiltration by macrophages and reduced angiogenesis. Interestingly, 4T1 cells that metastasized to the lung constitutively expressed elevated levels of MCP-1, and intravenous injection of 4T1 cells producing a high level of MCP-1 resulted in increased tumor foci in the lung of WT and MCP-1−/− mice. Thus, stromal cell-derived MCP-1 in the primary tumors promotes lung metastasis of 4T1 cells, but tumor cell-derived MCP-1 can also contribute once tumor cells enter the circulation. A greater understanding of the source and role of this chemokine may lead to novel strategies for cancer treatment.  相似文献   
110.
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