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71.
This study analyzed the variations in space of 8 body dimensions and 11 measures of the head of 1,244 adult Yemenite males, collected in 1933/34 by Coon in Yemen and in Hadhramawt. The aim was to evaluate the presence of geographic microdifferentiation of the populations settled in the different regions of Yemen at the time. Coon sub-divided the sample into six geographical areas according to birthplace and ethnicity of the individuals: Tihamah, the Western Mountains, the Central Plateau, the South Coast, the Eastern Mountains, and Hadhramawt. The results of ANCOVA (age as covariate) show that the observed differences of all variables among the six groups were highly statistically significant. Tukey's post-hoc test reveals higher statistically significant differences among four main groups: (1) Tihamah; (2) the Western Mountains and Central Plateau; (3) the Eastern Mountains; and (4) the Southern Coast and Hadhramawt. Multiple discriminant analysis carried out using only the data of the 11 measures of the head, the more "genetically" determined variables, confirmed these differences. Indeed, the first canonical variate well separates the groups with the Tihamah, Southern Coast and Hadhramawt on the one side and the Eastern Mountains, Western Mountains and Central Plateau on the other. The second canonical variate separates the Tihamah, Western Mountains and Central Plateau from the Eastern Mountains, Southern Coast and Hadhramawt. In conclusion, the Yemenite population seems to be composed of three morphologically distinct groups and an Eastern Mountains group which is positioned between the group formed by the Southern Coast and Hadhramawt and the Western Mountains and Central Plateau group. The Tihamah is the most distant from all the other groups. These differences are probably due to the presence/absence of geographical and cultural barriers that have favored/blocked the gene flow over the years. Indeed, the entire coastal bell, through the centuries, has constituted one of the principal commercial routes between the East, Africa, and the eastern Mediterranean, while the high inland mountains have isolated the remaining communities. This data is also confirmed by genetic studies. Finally, the average height (162.6 cm) of the global Yemenite population, compared to data from the other six middle-eastern Arab countries and Egypt, was found to be 3-6 cm less. This characteristic will be further studied, analyzing variations in average height according to the different age classes in order to evaluate any possible secular changes.  相似文献   
72.
There exist few standards of head length and breadth from childhood to adulthood in Europoid populations. Moreover, such standards are based on samples that cannot be used as references for all populations since they were taken from different ethnic groups and from different periods. The aims of this study were: (1) to test whether standards derived from North Americans of European extraction can be used to assess the Sardinian population; and (2) to produce growth charts for head length and breadth for Sardinian males and females from 3 to 22 years of age.The cross sectional sample consisted of 9,721 subjects of Sardinian origin (4,884 males and 4,837 females), aged 3–22 years, measured from 1998 to 2008. Growth percentiles were produced with the LMS method. The mean values for each sex in each age class (3–18 years) are almost always significantly lower for both head length and breadth than the corresponding North American values. The exceptions are the head length of boys of 14 years and girls of 16–18 years where values for Sardinians are lower, but not significantly so. The results show that the North American standards are not appropriate for the assessment of Sardinian children. For the Sardinian population, specific regional growth charts should be used to correctly evaluate the normal range and the cut-off points of the extreme percentiles.  相似文献   
73.
In many cancers hyaluronan content is increased, either by tumor cells or the surrounding stromal cells and this increased hyaluronan content correlates with unfavorable clinical prognosis. In the present work, we studied the effects of melanoma cell (aggressive melanoma cell line C8161)-derived factors on fibroblast hyaluronan synthesis, intracellular signaling, MMP expression and invasion. Treatment of the fibroblast cultures with melanoma cell conditioned medium (CM) caused accumulation of hyaluronan in the culture medium and formation of thick pericellular hyaluronan coat and hyaluronan cables. The expression of Has2 was increased approximately 20-fold by the C8161 melanoma cell CM, while Has1 and Has3 were increased twofold. Knock-down of Has2 expression with siRNA showed that Has2 was responsible for the increased hyaluronan synthesis induced by the melanoma cell CM. To find out the signaling routes, which led to Has2 upregulation, the phosphorylation profiles of 46 kinases were screened with phosphokinase array kit. Melanoma cell CM treatment strongly induced a rapid phosphorylation of p38, JNK, AKT, CREB, HSP27, STAT3 and cJUN. Treatment of the fibroblasts with specific inhibitors of PI3K, AKT and p38 reduced the melanoma cell CM-induced hyaluronan secretion, while the inhibitor of PDGFR totally blocked it. In addition, siRNA for PDGFRα/β inhibited Has2 upregulation in melanoma cell CM-treated fibroblasts. In parallel with the increased hyaluronan synthesis the melanoma cell CM-treated fibroblasts showed spindle shape, numerous long cell protrusions, enhanced MMP expression and increased invasion into collagen-Cultrex matrix. siRNA blocking of Has2 or PDGFRα/β expression reversed the stimulatory effect of melanoma cell CM on fibroblast invasion. PDGF secreted by melanoma cells thus mediated fibroblasts activation, with HAS2 upregulation as a major factor in the fibroblast response. This effect on stromal matrix is suggested to favor tumor growth.  相似文献   
74.
Density functional theory (DFT) methods were used to simulate the environment of vanadium in several V proteins, such as vanadyl-substituted carboxypeptidase (sites A and B), vanadyl-substituted chloroplast F(1)-ATPase (CF(1); site 3), the reduced inactive form of vanadium bromoperoxidase (VBrPO; low- and high-pH sites), and vanadyl-substituted imidazole glycerol phosphate dehydratase (IGPD; sites α, β, and γ). Structural, electron paramagnetic resonance, and electron spin echo envelope modulation parameters were calculated and compared with the experimental values. All the simulations were performed in water within the framework of the polarizable continuum model. The angular dependence of [Formula: see text] and [Formula: see text] on the dihedral angle θ between the V=O and N-C bonds and on the angle φ between the V=O and V-N bonds, where N is the coordinated aromatic nitrogen atom, was also found. From the results it emerges that it is possible to model the active site of a vanadium protein through DFT methods and determine its structure through the comparison between the calculated and experimental spectroscopic parameters. The calculations confirm that the donor sets of sites B and A of vanadyl-substituted carboxypeptidase are [[Formula: see text], H(2)O, H(2)O, H(2)O] and [N(His)(||), N(His)(⊥), [Formula: see text], H(2)O], and that the donor set of site 3 of CF(1)-ATPase is [[Formula: see text], OH(Thr), H(2)O, H(2)O, [Formula: see text]]. For VBrPO, the coordination modes [N(His)(||), N(His)(∠), OH(Ser), H(2)O, H(2)O(ax)] for the low-pH site and [N(His)(||), N(His)(∠), OH(Ser), OH(-), H(2)O(ax)] or [N(His)(||), N(His)(∠), [Formula: see text], H(2)O] for the high-pH site, with an imidazole ring of histidine strongly displaced from the equatorial plane, can be proposed. Finally, for sites α, β, and γ of IGPD, the subsequent deprotonation of one, two, and three imidazole rings of histidine and the participation of a carboxylate group of a glutamate residue ([N(His)(||), [Formula: see text], H(2)O, H(2)O], [N(His)(||), N(His)(||), [Formula: see text], H(2)O], and [N(His)(||), N(His)(||), [Formula: see text], OH(-), [Formula: see text]], respectively) seems to be the most plausible hypothesis.  相似文献   
75.
The red species of Cortinarius subgenus Dermocybe in Europe were studied based on morphological and molecular data. Three completely red species were recognized: C. sanguineus (syn. C. sanguineus var. aurantiovaginatus), C. puniceus (syn. C. cruentus, C. rubrosanguineus) and C. vitiosus comb. nov. Cortinarius sanguineus has dusky red to red pileus, reddish yellow mycelium and lacking or with only slightly encrusted hyphae in pileipellis. It occurs in mesic to damp forests with Picea, often on rich soil in the boreal and montane areas of Europe, presumably also in eastern Canada. Cortinarius puniceus differs from C. sanguineus by its stronger purplish red, narrower spores and spot-like encrusted hyphae in pileipellis. It grows with deciduous trees in the temperate zone of Europe. Cortinarius vitiosus is known only from Fennoscandia and occurs in dry to mesic coniferous forests. It has fairly thin, often zonate, dark red to dark reddish brown pileus, pale red mycelium, small spores and encrusted lamellar trama and pileipellis hyphae. In addition to these three species C. fervidus and C. phoeniceus occasionally have red basidiomes. The relationships of the species were inferred by analysis of ITS sequences. Our study suggests that the section Sanguinei, as earlier defined, is polyphyletic. Here the section is limited to include C. sanguineus, C. puniceus and North American D. sierraensis. The relationships with other red species were not determined. Section Dermocybe, including C. cinnamomeus, C. croceus and C. uliginosus, formed a monophyletic group, and the section Malicoriae had some support. A total of 34 new sequences are published including nine from type specimens.  相似文献   
76.
Pichia fermentans DiSAABA 726 is a biofilm-forming yeast that undergoes dimorphic transition. Under yeast-like morphology it controls brown rot caused by Monilia spp. on apple fruit, while under pseudohyphal form, it shows pathogenic behaviour itself on peach fruit. The present study investigates the nutritional factors that induce and separate yeast-like and pseudohyphal morphologies under laboratory conditions. We show that P. fermentans DiSAABA 726 produces mainly yeast-like cells on media containing millimolar concentrations of urea and diammonium phosphate, and forms pseudohyphae at micromolar concentrations of these two salts. With ammonium sulphate, yeast-like or pseudohyphal morphology depends on the N concentration and the pH of the culture media. Amino acids such as methionine, valine, and phenylalanine invariably induce pseudohyphal morphology irrespective of the N concentration and the pH of the culture media. Methionol, 1-butanol, isobutanol, and isopropanol induce pseudohyphal growth, while phenylethanol and isoamyl alcohol fail to induce the formation of filaments. Thus, the morphogenesis of P. fermentans DiSAABA 726 depends more on the nitrogen source than on the N concentration, and is regulated by the quorum-sensing molecules that are generally produced from amino-acid assimilation under nitrogen starvation.  相似文献   
77.
Phytoplankton populations can display high levels of genetic diversity that, when reflected by phenotypic variability, may stabilize a species response to environmental changes. We studied the effects of increased temperature and CO(2) availability as predicted consequences of global change, on 16 genetically different isolates of the diatom Skeletonema marinoi from the Adriatic Sea and the Skagerrak (North Sea), and on eight strains of the PST (paralytic shellfish toxin)-producing dinoflagellate Alexandrium ostenfeldii from the Baltic Sea. Maximum growth rates were estimated in batch cultures of acclimated isolates grown for five to 10 generations in a factorial design at 20 and 24°C, and present day and next century applied atmospheric pCO(2), respectively. In both species, individual strains were affected in different ways by increased temperature and pCO(2). The strongest response variability, buffering overall effects, was detected among Adriatic S. marinoi strains. Skagerrak strains showed a more uniform response, particularly to increased temperature, with an overall positive effect on growth. Increased temperature also caused a general growth stimulation in A. ostenfeldii, despite notable variability in strain-specific response patterns. Our data revealed a significant relationship between strain-specific growth rates and the impact of pCO(2) on growth-slow growing cultures were generally positively affected, while fast growing cultures showed no or negative responses to increased pCO(2). Toxin composition of A. ostenfeldii was consistently altered by elevated temperature and increased CO(2) supply in the tested strains, resulting in overall promotion of saxitoxin production by both treatments. Our findings suggest that phenotypic variability within populations plays an important role in the adaptation of phytoplankton to changing environments, potentially attenuating short-term effects and forming the basis for selection. In particular, A. ostenfeldii blooms may expand and increase in toxicity under increased water temperature and atmospheric pCO(2) conditions, with potentially severe consequences for the coastal ecosystem.  相似文献   
78.
The habit of mining within leaves has evolved convergently in numerous plant-feeding insect taxa. Many leaf-mining groups contain a large number of species with distinct feeding preferences, which makes them highly suitable for studies on the evolutionary history of host-plant use and on the role of niche shifts in speciation. We aimed to clarify the origin, classification, and ecological evolution of the tenthredinid sawfly subfamily Heterarthrinae, which contains c. 150 leaf-mining species that collectively feed on over 20 plant genera around the world. For this, we reconstructed the phylogeny of representative heterarthrine species and diverse outgroups from the superfamily Tenthredinoidea on the basis of DNA sequence data collected from two mitochondrial (CoI and Cytb) and two nuclear (EF-1α and NaK) genes. Thereafter, we inferred the history of niche diversification within Heterarthrinae by plotting larval host-plant associations on the trees, and by contrasting a time-calibrated leaf-miner phylogeny with the phylogeny of their host plants. The results show that: (1) heterarthrine leaf-miners constitute a monophyletic group that arose from external-feeding blennocampine lineages within the Tenthredinidae c. 110-80 million years ago; (2) heterarthrines generally radiated well after their host taxa, and extant host-plant associations therefore result from a combination of host conservatism and occasional shifts among available plant taxa; and (3) diversification in Heterarthrinae apparently occurs by multiple mechanisms, including sympatric or allopatric ecological speciation, non-ecological allopatric speciation, and possibly allochronic speciation. Overall, both present and historical host-use patterns within the Heterarthrinae exhibit striking similarities to patterns found in co-occurring herbivore taxa.  相似文献   
79.
Podocytes are insulin-sensitive and take up glucose in response to insulin. This requires nephrin, which interacts with vesicle-associated membrane protein 2 (VAMP2) on GLUT4 storage vesicles (GSVs) and facilitates their fusion with the plasma membrane. In this paper, we show that the filament-forming GTPase septin 7 is expressed in podocytes and associates with CD2-associated protein (CD2AP) and nephrin, both essential for glomerular ultrafiltration. In addition, septin 7 coimmunoprecipitates with VAMP2. Subcellular fractionation of cultured podocytes revealed that septin 7 is found in both cytoplasmic and membrane fractions, and immunofluorescence microscopy showed that septin 7 is expressed in a filamentous pattern and is also found on vesicles and the plasma membrane. The filamentous localization of septin 7 depends on CD2AP and intact actin organization. A 2-deoxy-d-glucose uptake assay indicates that depletion of septin 7 by small interfering RNA or alteration of septin assembly by forchlorfenuron facilitates glucose uptake into cells and further, knockdown of septin 7 increased the interaction of VAMP2 with nephrin and syntaxin 4. The data indicate that septin 7 hinders GSV trafficking and further, the interaction of septin 7 with nephrin in glomeruli suggests that septin 7 may participate in the regulation of glucose transport in podocytes.  相似文献   
80.
Multiple Sclerosis (MS) is the most common progressive and disabling neurological condition affecting young adults in the world today. From a genetic point of view, MS is a complex disorder resulting from the combination of genetic and non-genetic factors. We aimed to identify previously unidentified loci conducting a new GWAS of Multiple Sclerosis (MS) in a sample of 296 MS cases and 801 controls from the Spanish population. Meta-analysis of our data in combination with previous GWAS was done. A total of 17 GWAS-significant SNPs, corresponding to three different loci were identified:HLA, IL2RA, and 5p13.1. All three have been previously reported as GWAS-significant. We confirmed our observation in 5p13.1 for rs9292777 using two additional independent Spanish samples to make a total of 4912 MS cases and 7498 controls (ORpooled = 0.84; 95%CI: 0.80-0.89; p = 1.36 × 10-9). This SNP differs from the one reported within this locus in a recent GWAS. Although it is unclear whether both signals are tapping the same genetic association, it seems clear that this locus plays an important role in the pathogenesis of MS.  相似文献   
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