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1.
Primer sequences and initial characterization are presented for 10 microsatellite loci isolated from the German cockroach, Blattella germanica. In a sample of 30 individuals from a single population sample, all loci were polymorphic with two to 12 alleles segregating per locus and levels of observed heterozygosity ranging from 0.27 to 0.92. One locus showed a deficit of heterozygotes. Experimental conditions are described for polymerase chain reaction multiplexing, which enables the genotyping of eight loci in three electrophoretic runs consisting of one set of three and two sets of two markers. Seven primer sets cross‐amplify in the related Blattella asahinai.  相似文献   
2.
Sulfamide and sulfamic acid are the simplest compounds containing the SO2NH2 moiety, responsible for binding to the Zn(II) ion within carbonic anhydrase (CA, EC 4.2.1.1) active site, and thus acting as inhibitors of the many CA isozymes presently known. Here we describe two novel classes of CA inhibitors obtained by derivatizations of the lead molecules mentioned above. The new compounds, possessing the general formula RSO2NH-SO2X (X = OH, NH2), were obtained by reaction of sulfamide or sulfamic acid with alkyl/arylsulfonyl halides or arylsulfonyl isocyanates. A smaller series of derivatives has been obtained by reaction of aromatic aldehydes with sulfamide, leading to Schiff bases of the type ArCH = NSO2NH2. All the new compounds act as strong inhibitors of isozymes I, II and IV of carbonic anhydrase. Their mechanism of CA inhibition is also discussed based on electronic spectroscopic measurements on adducts with the Co(II)-substituted enzyme. These experiments led to the conclusion that the new inhibitors are directly coordinated (in a monodentate manner) to the metal ion within the enzyme active site, similarly to the classical inhibitors, the aromatic/heterocyclic sulfonamides.  相似文献   
3.
Reaction of o- or p-hydroxybenzaldehydes with sulfanilamide, homosulfanilamide and p-(2-aminoethyl)- benzene-sulfonamide afforded several new Schiff bases which were subsequently derivatized at the phenolic hydroxy moiety by reaction with arylsulfonylisocyanates. The new arylsulfonylcarbamates obtained in this way possessed interesting inhibitory properties against three carbonic anhydrase (CA) isozymes, hCA I, hCA II and bCA IV (h = human, b = bovine isozyme). All these new derivatives, the simple Schiff bases and the arylsulfonylcarbamates obtained as outlined above, were more inhibitory against all isozymes as compared to the corresponding parent sulfonamide from which they were obtained. Generally, the p-hydroxybenzaldehyde derivatives were more active than the corresponding ortho isomers. An interesting behavior was evidenced for some of the ortho-substituted arylsulfonylcarbamato-sulfonamides, which showed higher affinities for the isozyme hCA I, as compared to hCA II and bCA IV (generally hCA I is 10-1000 less sensitive to "normal" sulfonamide inhibitors, such as acetazolamide, methazolamide or dorzolamide, as compared to hCA II). This make the new derivatives attractive leads for designing isozyme I-specific inhibitors.  相似文献   
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Glucorticoids are potent drugs that have a multitude of pharmacological actions both at genomic and non-genomic levels. Many of the diseases in which glucorticoids are routinely administered are featured by angiogenesis and enhanced capillary permeability, permitting targeted delivery using long-circulating drug delivery systems. By encapsulation of glucorticoids in long-circulating liposomes, drug levels at the site of the pathology are markedly higher, increasing and prolonging therapeutic efficacy in models of rheumatoid arthritis, multiple sclerosis, and cancer.  相似文献   
7.
Important physiological and physio-pathological functions are played by several carbonic anhydrase (CA, EC 4.2.1.1) isozymes, which are strongly inhibited by aromatic and heterocyclic sulfonamides. Here we report several new types of such sulfonamides, incorporating furan-, thiophene- and pyrrole-carboxamide moieties in their molecules. Some of these compounds showed very good CA II and CA IV inhibitory properties. with affinities for the enzymes in the low nanomolar range. Due to their relatively low water solubility, some of the most active CA II inhibitors reported here have been formulated as aqueous suspension for topical administration as antiglaucoma agents. in normotensive and glaucomatous rabbits. The derivatives incorporating furan- and pyrrole-carboxamide moieties (but not the corresponding thiophene-substituted derivatives), showed effective and long-lasting intraocular pressure (IOP) lowering both in normotensive as well as glaucomatous animals, with potencies superior to dorzolamide and brinzolamide, the two available topically acting sulfonamide drugs. This is the first example of non-water soluble sulfonamides that significantly lower IOP, being thus similar with the recently introduced drug brinzolamide, which belongs to a completely different chemical family of antiglaucoma sulfonamides.  相似文献   
8.
This study evaluates whether the inhibitory effects of prednisolone phosphate (PLP) encapsulated in long-circulating liposomes (LCL-PLP) on tumor growth and tumor angiogenesis described previously can be generalized to other types of glucocorticoids (GC) encapsulated in LCL (LCL-GC). Four types of synthetic GC, i.e. budesonide disodium phosphate (BUP), dexamethasone disodium phosphate (DXP), methylprednisolone disodium phosphate (MPLP), and PLP, were selected based on the difference in their potency to activate the human glucocorticoid receptor. The effects of all LCL-GC on the production of angiogenic/inflammatory factors in vivo in the B16.F10 murine melanoma model as well as on the viability and proliferation of tumor cells and endothelial cells in vitro were investigated. Our results show that all four selected LCL-GC formulations inhibit tumor growth, albeit to different degrees. The differences in antitumor activity of LCL-GC correlate with their efficacy to suppress tumor angiogenesis and inflammation. The strongest antitumor effect is achieved by LCL-encapsulated BUP (LCL-BUP), due to the highest potency of BUP versus the other three GC types. The in vitro results presented herein suggest that LCL-BUP has strong cytotoxic effects on B16.F10 melanoma cells and the anti-proliferative effects of all LCL-GC towards angiogenic endothelial cells play a role in their antitumor activity.  相似文献   
9.
We report a novel weathering mechanism in South African sandstone formations, where cryptoendolithic cyanobacteria induce weathering by substrate alkalization during photosynthesis. As a result, the upper rock part is loosened and then eroded away by physical forces such as wind, water, trampling. This special type of ‘exfoliation’ is widely distributed and affects the geomorphology of whole sandstone mountain ranges and outcrops across several biomes. We show, that this weathering type is initiated by bioalkalization because of the photosynthesis of cryptoendolithic (i.e. those organisms living in small tight open spaces between the sand grains) cyanobacteria causing pH values high enough to enhance silica solution in the cryptoendolithic zone. As modern cyanobacteria are the initial photoautotrophic colonizers of bare rocks in arid and semiarid landscapes, it is possible that they may also have played a significant role in shaping sandstone landscapes in the geological past.  相似文献   
10.
Elaborate horns or horn‐like structures in male scarab beetles commonly scale with body size either (a) in a linear fashion with horn size increasing relatively faster than body size or (b) in a threshold‐dependent, sigmoid fashion; that is, males smaller than a certain critical body size develop no or only rudimentary horns, whereas males larger than the threshold size express fully developed horns. The development of linear vs. sigmoid scaling relationships is thought to require fundamentally different regulatory mechanisms. Here we show that such disparate regulatory mechanisms may co‐occur in the same individual. Large males of the south‐east Asian Onthophagus (Proagoderus) watanabei (Ochi & Kon) (Scarabaeidae, Onthophagini) develop a pair of long, curved head horns as well as a single thoracic horn. We show that unlike paired head horns in a large number of Onthophagus species, in O. watanabei the relationship between head horns and body size is best explained by a linear model. Large males develop disproportionately longer horns than small males, but the difference in relative horn sizes across the range of body sizes is small compared to other Onthophagus species. However, the scaling relationship between the thoracic horn and body size is best explained by a strongly sigmoid model. Only males above a certain body size threshold express a thoracic horn and males smaller than this threshold express no horn at all. We found a significant positive correlation between head and thoracic horn length residuals, contrary to what would be expected if a resource allocation tradeoff during larval development would influence the length of both horn types. Our results suggest that the scaling relationship between body size and horn length, and the developmental regulation underlying these scaling relationships, may be quite different for different horns, even though these horns may develop in the same individual. We discuss our results in the context of the developmental biology of secondary sexual traits in beetles. © 2004 The Linnean Society of London, Biological Journal of the Linnean Society, 2004, 83 , 473–480.  相似文献   
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