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Systematic Parasitology - This paper presents a review of host specificity among cestodes collected from Soricidae mammals in Europe and a revision of cestodes preserved in formalin in the...  相似文献   
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Haemosporida is a diverse group of vector-borne parasitic protozoa, ubiquitous in terrestrial vertebrates worldwide. The renewed interest in their diversity has been driven by the extensive use of molecular methods targeting mitochondrial genes. Unfortunately, most studies target a 478?bp fragment of the cytochrome b (cytb) gene, which often cannot be used to separate lineages from different genera found in mixed infections that are common in wildlife. In this investigation, an alignment constructed with 114 mitochondrial genome sequences belonging to four genera (Leucocytozoon, Haemoproteus, Plasmodium and Hepatocystis) was used to design two different sets of primers targeting the cytb gene as well as the other two mitochondrial DNA genes: cytochrome c oxidase subunit 1 and cytochrome c oxidase subunit 3. The design of each pair of primers required consideration of different criteria, including a set for detection and another for differential amplification of DNA from parasites belonging to different avian haemosporidians. All pairs of primers were tested in three laboratories to assess their sensitivity and specificity under diverse practices and across isolates from different genera including single and natural mixed infections as well as experimental mixed infections. Overall, these primers exhibited high sensitivity regardless of the differences in laboratory practices, parasite species, and parasitemias. Furthermore, those primers designed to separate parasite genera showed high specificity, as confirmed by sequencing. In the case of cytb, a nested multiplex (single tube PCR) test was designed and successfully tested to differentially detect lineages of Plasmodium and Haemoproteus parasites by yielding amplicons with different sizes detectable in a standard agarose gel. To our knowledge, the designed assay is the first test for detection and differentiation of species belonging to these two genera in a single PCR. The experiments across laboratories provided recommendations that can be of use to those researchers seeking to standardise these or other primers to the specific needs of their field investigations.  相似文献   
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Four different silica sol-gel films: methyltrimethoxysilane (MTMOS), tetraethoxysilane (TEOS), 3-aminopropyltriethoxysilane (APTOS) and 3-glycidoxypropyl-trimethoxysilane (GOPMOS) assembled onto highly oriented pyrolytic graphite (HOPG) were characterized using atomic force microscopy (AFM), due to their use in the development of glucose biosensors. The chemical structure of the oxysilane precursor and the composition of the sol-gel mixture both influenced the roughness, the size and the distribution of pores in the sol-gel films, which is relevant for enzyme encapsulation. The GOPMOS sol-gel film fulfils all the morphological characteristics required for good encapsulation of the enzyme, due to a smooth topography with very dense and uniform distribution of only small, 50nm diameter, pores at the surface. APTOS and MTMOS sol-gel films developed small pores together with large ones of 300-400nm that allow the leakage of enzymes, while the TEOS film formed a rough and incomplete network on the electrode, less suitable for enzyme immobilisation. GOPMOS sol-gel film with encapsulated glucose oxidase and poly(neutral red) redox mediator, prepared by in situ electropolymerization, were also morphologically characterized by AFM. The AFM results explain the variation of the stability in time, sensitivity and limit of detection obtained with different oxysilane sol-gel encapsulated glucose oxidase biosensors with redox mediator.  相似文献   
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Gastrointestinal cancers (gastric, pancreatic and colorectal) are life-threatening diseases, which easily spread to peritoneal cavity (Juhl et al. in Int J Cancer 57:330–335, 1994; Schneider et al. in Gastroenterology 128:1606–1625, 2005; Geer and Brennan in Am J Surg 165:68–72 1993). Application of hyperthermal intraperitoneal chemotherapy (HIPEC) is one of the choices treating these malignancies and prolonging patient survival time. Despite numbers of clinical trials showing positive effects of HIPEC against various types of cancer, the question whether hyperthermia significantly potentiate the cytotoxicity of cisplatin remains unanswered. Little information is available on the HIPEC effect at the level of mitochondria. To define the effect of hyperthermia (40 °C and 43 °C) to cisplatin treated human gastric AGS, pancreatic T3M4 and colorectal Caco-2 cancer cells, we established an in vitro experiment, which mimics clinical HIPEC conditions. Giving the importance of mitochondrial energy metabolism in cancer, we investigated the effect of cisplatin and hyperthermia on mitochondrial Complex-I (glutamate/malate) and complex-II (succinate) dependent respiratory rates, the coupling of oxidative phosphorylation, the proton permeability of mitochondrial inner membrane and on the integrity of mitochondrial outer membrane in Caco-2, AGS and T3M4 cancer cell lines. Our main findings are: 1) treatment of cells with cisplatin causes the impairment of mitochondrial functions – the increase in the proton permeability of mitochondrial inner membrane and decrease in the oxidative phosphorylation efficiency in Caco-2, AGS and T3M4 cancer cells; 2) hyperthermia (40 °C and 43 °C) increased state 2 respiration rate only in AGS cells without any effects on Caco-2 and T3M4 cells; 3) hyperthermia in combination with cisplatin doesn’t enhance cisplatin effect neither in Caco-2 and T3M4 nor in AGS cells. Thus, our results show the different mitochondrial response of gastric AGS, pancreatic T3M4 and colorectal Caco-2 cancer cells to cisplatin or/and hyperthermia – treatment. Further studies are needed to find the mechanisms of cell line - specific mitochondrial response to cisplatin and hyperthermia.  相似文献   
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Parastizopus armaticeps (Coleoptera: Tenebrionidae), a nocturnal fossorial detritivore inhabiting southern Kalahari dunes, aggregates in burrows during the day. Group size increases during drought but 25% of beetles are still found alone or in pairs. During drought, beetles from large groups leave burrows after sunset synchronously and carlier than pairs and single animals and earlier than beetles of any group size after rain. Detritus from the beetles' major foodplant is scarce and food competition high. Beetles emerging early preferentially select and carry high-quality transportable items into burrows to eat (forage); late-emerging ones feed on the low-quality large twigs on the surface. Foraging is shown to be a strategy to secure food items against surface competitors, not one to reduce body water loss during surface exposure. The costs and benefits of group vs. solitary lifestyles and alternate hypotheses for early and synchronous emergence were tested experimentally. Grouped beetles had lower body water loss rates but, due to competition with burrow mates, higher feeding costs than single ones. It is hunger that advances and thus synchronizes emergence time, not social facilitation. Field data support a model predicting that, for maximal benefits, beetles should alternate between solitary and group life at optimal time intervals.  相似文献   
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