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The genital anatomy of Orcula jetschini (Romania), Orcula zilchi (Bulgaria), and Orcula wagneri (Albania) is described. Based on anatomical features (morphology of the penial caecum) shell characters (sculpture and shape) and unpublished molecular data the genus Orcula is subdivided into three subgenera. Orcula zilchi was classified within the monotypic subgenus Orcula (Hausdorfia) subgen. n.; Orcula jetschini, Orcula wagneri, and Orcula schmidtii were classified to Orcula (Illyriobanatica) subgen. n. (type species: Pupa schmidtii) whereas the other Orcula species remain in the nominotypical subgenus. Orcula (Hausdorfia) is known from South-Eastern Bulgaria and North-Western Turkey, Orcula (Illyriobanatica) inhabits Western Romania, North-Western Greece, Albania, Macedonia, Kosovo, and Montenegro. The nine species of Orcula (Orcula) are known mainly from the Alps and the Western Carpathians (from Eastern France to Eastern Hungary and Slovakia).The occurrence of only one Orcula species namely Orcula jetschini is verified from Romania. Available information suggests that data on the Romanian occurrence of Orcula dolium and Orcula gularis were based on wrongly identified specimens. Sphyradium dobrogicum (=Orcula dobrogica) is considered as a synonym of Sphyradium doliolum.  相似文献   
43.
Cancer represents a heterogeneous disease with multiple levels of regulation and a dynamic environment that sustains the evolution of the malignant mass. This dynamic is in part sustained by a class of extracellular vesicles termed exosomes that are able to imprint the pathological state by incorporating differential cargos in order to facilitate cell-to-cell communication. Exosomes are stable within the extracellular medium and function as shuttles secreted by healthy or pathological cells, being further taken by the accepting cell with direct effects on its phenotype. The exosomal trafficking is deeply involved in multiple levels of cancer development with roles in all cancer hallmarks. Nowadays, studies are constantly exploring the ability of exosomes to sustain the malignant progression in order to attack this pathological trafficking and impair the ability of the tumor mass to expand within the organisms. As important, the circulatory characteristics of exosomes represent a steady advantage regarding the possibility of using them as minimally invasive diagnosis tools, where cancer patients’ present modified exosomal profiles compared to the healthy ones. This last characteristic, as novel diagnosis tools, has the advantage of a possible rapid transition within the clinic, compared to the studies that evaluate the therapeutic meaning.  相似文献   
44.
Acyl-CoA carboxylases (ACC) are involved in important primary or secondary metabolic pathways such as fatty acid and/or polyketides synthesis. In the 62 kb fragment of pccB gene locus of Streptomyces toxytricini producing a pancreatic inhibitor lipstatin, 3 distinct subunit genes of presumable propionyl-CoA carboxylase (PCCase) complex, assumed to be one of ACC responsible for the secondary metabolism, were identified along with gene for a biotin protein ligase (Bpl). The subunits of PCCase complex were a subunit (AccA3), P subunit (PccB), and auxiliary ɛ subunit (PccE). In order to disclose the involvement of the PCCase complex in secondary metabolism, some biochemical characteristics of each subunit as well as their complex were examined. In the test of substrate specificity of the PCCase complex, it was confirmed that this complex showed much higher conversion of propionyl-CoA rather than acetyl-CoA. It implies the enzyme complex could play a main role in the production of methylmalonyl-CoA from propionyl-CoA, which is a precursor of secondary polyketide biosynthesis.  相似文献   
45.
Hairy root cultures of Salvia tomentosa were initiated by transformation with Agrobacterium rhizogenes. To prevent necrosis in the explants and to protect young hairy roots, Amberlite XAD-4 resin, in combination with a temporary immersion cultivation system, was applied. HPLC analyzes showed that the resin adsorbed more than 93% of the released phenolic acids and 100% of the released flavonoids. The decreased content of the released phenolics significantly reduced their destructive effects on the plant tissues, prevented, and speeded up the appearance of hairy roots.  相似文献   
46.
Atanasov AT 《Bio Systems》2007,90(1):224-233
The aim of this study is to establish and calculate the exact allometric relationship between the total metabolic energy per life span and the body mass in a wide range of mammals with about six orders of magnitude variation of the body mass of animals. The study shows that it exists a linear relationship between the total metabolic energy per life span PT(ls) (kJ) and the body mass M (kg) of 95 mammals (3 monotremes, Subclass Prototheria, 16 marsupialis (Subclass Theria, Infraclass Metatheria) and 76 placentals (Subclass Theria, Infraclass Eutheria)) from type: PT(ls)=A(ls)(+)M(1.0511), where P (kJ/day) is the basal rate of metabolism and T(ls) (days) is the mean life span of animals. The linear coefficient A(ls)(+)=7.158x10(5) kJ/kg is the total metabolic energy, exhausted during the life span per 1 kg body mass of the animals. The mean values of the total metabolic energy per life span, per unit body mass (A(ls)) for orders from Subclass Prototheria and Theria (Infraclass Metatheria) and orders Xenarthra, Pholidota, Soricomorpha, Rodentia (Infraclass Eutheria) varied negligible in interval (4.656-5.80)x10(5) kJ/kg. The coefficient A(ls) grows from (7.68-8.36)x10(5) kJ/kg in Lagomorpha and Artiodactyla (Eutheria) to (10.58-12.64)x10(5) kJ/kg in orders Carnivora, Pinnipeda and Chiroptera (Eutheria). A(ls) grows maximum to 18.5x10(5) kJ/kg in Primates. Thus, the values of coefficient A(ls) differ maximum four-fold in all orders. Across the all species the values of A(ls) are changes about one order of magnitude. Consequently, our survey shows that the changes of the body mass, basal metabolic rate and the life span of animals are three mutually related parameters, so that the product A(ls)=(PT(ls))/M remains relatively constant in comparison to 1 million fold difference in body mass and total metabolic energy per life span between mammals.  相似文献   
47.
Hairy root type plant in vitro systems as sources of bioactive substances   总被引:6,自引:0,他引:6  
“Hairy root” systems, obtained by transforming plant tissues with the “natural genetic engineer” Agrobacterium rhizogenes, have been known for more than three decades. To date, hairy root cultures have been obtained from more than 100 plant species, including several endangered medicinal plants, affording opportunities to produce important phytochemicals and proteins in eco-friendly conditions. Diverse strategies can be applied to improve the yields of desired metabolites and to produce recombinant proteins. Furthermore, recent advances in bioreactor design and construction allow hairy root-based technologies to be scaled up while maintaining their biosynthetic potential. This review highlights recent progress in the field and outlines future prospects for exploiting the potential utility of hairy root cultures as “chemical factories” for producing bioactive substances.  相似文献   
48.
The early secretory pathway (ESP) consisting of the endoplasmic reticulum (ER), pre-Golgi intermediates and the Golgi stack links protein synthesis to folding and vesicle trafficking to generate the membrane architecture of the eukaryotic cell. The fundamental principles that contribute to organization of the ESP remain largely unknown. We raise the possibility that assembly of the ESP is largely built on a foundation that is influenced by the kinetic and thermodynamic properties of the protein fold. Folding energetics may provide an adjustable platform for adaptor-dependent interactions with the transport machinery, suggesting the possibility that protein cargo energetics plays a central role in directing both trafficking patterns and global compartmental organization of the ESP. In this view, cargo energetics likely coordinates the composition and maturation of ER and Golgi compartments with the physiological state of the cell in different tissue and environmental settings.  相似文献   
49.
The alkaloid patterns of sea daffodil (Pancratium maritimum L.) shoot culture, cultivated in a temporary immersion cultivation system were investigated. The shoots accumulated maximal amounts of biomass (0.8 g dry biomass/L and Growth Index?=?1.6) at immersion frequency with 15 min flooding and 12 h stand-by periods. At this regime P. maritimum shoots achieved the highest degree of utilization of carbon source. Twenty-two alkaloids, belonging to narciclasine, galanthamine, haemanthamine, lycorine, montanine, tazettine, homolycorine and tyramine types were identified in intracellular and extracellular alkaloid extracts. The immersion frequency affected strongly the capacity of alkaloid biosynthesis in P. maritimum shoots and at the optimum conditions of cultivation, the total intracellular alkaloid content reached up to 3,469 μg/g dry biomass. The main biosynthesized alkaloids were haemanthamine (900.1 μg/g) and lycorine (799.9 μg/g). The obtained results proved that temporary immersion technology, as a cultivation approach, and P. maritimum shoots, as a biological system, are prospective for producing wide range bioactive alkaloids.  相似文献   
50.
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