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The Historic Sanctuary of Machu Picchu (Cusco, Peru) is one of the most important archaeological monuments in Peru and worldwide. Machu Picchu is classified as a UNESCO World Heritage site and at risk from climatic change. However, the seismic centennial history of Peru reports large earthquakes generated both along the subduction zone (Mw8) and on active crustal faults along the Andean Cordillera (Mw7). It is therefore important to know if Machu Picchu is located in an area of seismic hazard and then to take measures to mitigate potential seismic hazards. Due to the short historical earthquake catalogue (< 500 years) and the absence of significant recent instrumental seismicity in the site's vicinity (radius of < 30 km), our knowledge about the seismic hazard in Machu Picchu is limited. The earthquakes of 1650 and 1950 affected Cusco city and surrounding areas, but without damage descriptions in Machu Picchu (80 km away) (Silgado Ferro 1978). In this study, we make the first attempt to use the analysis of earthquake archaeological effects (EAEs) and their differentiation from the effects generated by slope movements (creep) to investigate the past occurrence of strong earthquakes at the site. The application of geological structural analysis to the deformations observed in Machu Picchu shows two directions of the mean ground movement: N020° E and N110° E. Two earthquakes that affected Machu Picchu during its construction generated these directions. This kind of data should be used in the future to protect this important archaeological site. [ABSTRACT FROM AUTHOR]

A comparative proteomic approach was performed to analyze the differential accumulation of leaf proteins in response to the symbiosis between Solanum lycopersicum and the arbuscular mycorrhizal fungus (AMF) Rhizophagus irregularis. Protein profiling was examined in leaves from tomato plants colonized with AMF ( M), as well as non-colonized plants fertilized with low phosphate (20 μM P; NM-LP) and non-colonized plants fertilized with regular phosphate Hoagland's solution (200 μM P; NM-RP). Comparisons were made between these groups, and 2D-SDS-PAGE revealed that 27 spots were differentially accumulated in M vs. NM-LP. Twenty-three out of the 27 spots were successfully identified by mass spectrometry. Two of these proteins, 2-methylene-furan-3-one reductase and auxin-binding protein ABP19a, were up-accumulated in M plants. The down-accumulated proteins in M plants were associated mainly with photosynthesis, redox, and other molecular functions. Superoxide dismutase, harpin binding protein, and thioredoxin peroxidase were down-accumulated in leaves of M tomato plants when compared to NM-LP and NM-RP, indicating that these proteins are responsive to AMF colonization independently of the phosphate regime under which they were grown. 14-3-3 protein was up-accumulated in NM-RP vs. NM-LP plants, whereas it was down-accumulated in M vs. NM-LP and M vs. NM-RP, regardless of their phosphate nutrition. This suggests a possible regulation by P nutrition and AMF colonization. Our results demonstrate AMF-induced systemic changes in the expression of tomato leaf proteins, including the down-accumulation of proteins related to photosynthesis and redox function. [ABSTRACT FROM AUTHOR]

The effect of population density of Tetraoychus urticae Koch on CO2 assimilation, transpiration and stomatal behaviour in rose leaves and on the diameter and length of stems and flower buds was investigated under greenhouse conditions. The investigation was performed in order to gain more insight into integrated control systems in rose crops grown under greenhouse conditions. Physiological processes, such as photosynthesis and transpiration, as well as stomatal behaviour and chlorophyll content, were studied as they form part of the plant's nutrition mechanism and therefore affect the quantity and quality of the flowers. Information related to the effect of spider mite population density on bloom quality, diameter and length of stems and flower buds was also collected. The data indicate that increased mite density coincides with a decrease in the net photosynthetic rate, transpiration and chlorophyll content. Higher mite densities on leaves cause stomata to remain open for longer periods, which allows a greater loss of water. Spider mite densities of 10 and 50 mites per leaf cause a reduction in flower stem length of 17 and 26%, respectively, as compared to plants with no mites present. [ABSTRACT FROM AUTHOR]

According to epidemiological studies, gallstone disease is a very common disease in Mexican-Americans and Mexicans. However, the major risk factors for cholelithiasis in Mexicans have not been identified. We designed a case-control study in a group of Mexican subjects with and without gallstone disease confirmed by ultrasound. These subjects were prospectively studied over a three-year period. Clinical and epidemiological data were collected by means of a questionnaire. A total of 1500 subjects were included in this study: 1000 with and 500 without gallstone disease. The major risk factor in both men and women was body mass index [odds ratio (OR) 1.64 and 1.96, respectively; P < 0.008 and 0.001]. In addition, parity was an important factor in women (OR 2.17, P < 0.001), whereas age was associated with gallstone disease in men (OR 1.43, P < 0.001). We found that body mass index, parity, and age were the principal risk factors for gallstone disease in this group of Mexican subjects. These results are similar to those found in Mexican-American populations. [ABSTRACT FROM AUTHOR]

We compared the high-density lipoprotein (HDL) composition and particle heterogeneity in 60 non-obese (normal body mass index, BMI) men suffering from coronary artery disease (CAD) with normolipemia and normoinsulinemia with lower and higher insulin output during the oral glucose tolerance test (silent hyperinsulinemia). The apolipoprotein apoAI, apoAII, and apoE levels were higher in the high insulin response (HI) group than in low insulin response (LI) group. The ratio of apoAI versus total protein and the ratio of apoAI versus total cholesterol were increased in HI compared with LI. The lipid components in HDL were higher in HI than in HI, while for DHL2 they were higher in HI. The fractioning of HDL by gradient gel electrophoresis revealed a different pattern of HDL particles in both groups. The larger particles, HDL2b and HDL2a (mean particle diameters 10.6 and 9.2 nm, respectively), occur more frequently in HI patients (up to 60%) than in LI patients, whereas the smaller particles, HDL3a and HDL3b (mean particle diameters 8.6 and 7.8 nm, respectively), predominate in LI patients. Our results demonstrate that even in the normoglycemic, normocholesterolemic CAD patients, a high insulin output observed during the oral glucose tolerance test may be connected with a different HDL particle pattern, which suggests changes in the reverse cholesterol transport. [ABSTRACT FROM AUTHOR]