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Soil organic matter (SOM) constitutes roughly 60% organic carbon (OC) and therefore plays a crucial role in regulating global climate. However, our understanding of the long-term dynamics of the soil carbon pool remains constrained by limitations in analytical approaches capable of providing high resolution molecular-level information from arguably the most complex biomaterial on the planet. In this contribution, we combine hydrofluoric acid (HF) treatment with a spectroscopic approach as a strategy to provide refined molecular-level information on the interactions between soil minerals and SOM. Critically, we have not seen the use of this combined approach anywhere in the literature and strongly believe that it could allow us to improve our overall understanding to the mechanisms and pathways that regulate SOM transformation. Results clearly illustrates which organic structures are preferentially adsorbed to soil minerals and are likely to be protected from degradation, as well as spatial co-variations of SOM with specific mineral components such as Al3+, Si4+ and dibasic cations such as Mg2+as a function of their importance in the interaction process.•Soil samples were collected from different land-use types in rural farming communities of the Upper Rio Grande Valley.•Samples were oven dried, disaggregated, sieved, treated with 10% HF, rinsed and oven dried.•Oven dried samples were subjected to Mid-infrared (4000-400 cm-1), XRD and ED-XRF analyses.

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Peruvianin-I is a cysteine peptidase (EC 3.4.22) purified from Thevetia peruviana. Previous studies have shown that it is the only germin-like protein (GLP) with proteolytic activity described so far. In this work, the X-ray crystal structure of peruvianin-I was determined to a resolution of 2.15 Å (PDB accession number: 6ORM) and its specific location was evaluated by different assays. Its overall structure shows an arrangement composed of a homohexamer (a trimer of dimers) where each monomer exhibits a typical ß-barrel fold and two glycosylation sites (Asn55 and Asn144). Analysis of its active site confirmed the absence of essential amino acids for typical oxalate oxidase activity of GLPs. Details of the active site and molecular docking results, using a specific cysteine peptidase inhibitor (iodoacetamide), were used to discuss a plausible mechanism for proteolytic activity of peruvianin-I. Histological analyses showed that T. peruviana has articulated anastomosing laticifers, i.e., rows of cells which merge to form continuous tubes throughout its green organs. Moreover, peruvianin-I was detected exclusively in the latex. Because latex peptidases have been described as defensive molecules against insects, we hypothesize that peruvianin-I contributes to protect T. peruviana plants against herbivory.

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The germin-like protein (GLP) purified from Thevetia peruviana, Peruvianin-I, is the only one described as having proteolytic activity. Therefore, the goal of this study was to investigate the structural features responsible for its enzymatic activity. Although the amino acid sequence of Peruvianin-I showed high identity with other GLPs, it exhibited punctual mutations, which were responsible for the absence of oxalate oxidase activity. The phylogenetic analysis showed that Peruvianin-I does not belong to any classification of GLP subfamilies. Moreover, Peruvianin-I contains a catalytic triad found in all plant cysteine peptidases. Molecular docking simulations confirmed the role of the catalytic triad in its proteolytic activity. Synchrotron radiation circular dichroism assays confirmed that Peruvianin-I was stable at pH ranging from 5.0 to 8.0 and that it presented significant structural changes only above 60 °C. The addition of iodoacetamide caused changes in its native conformation, but only a slight effect was observed after adding a reducing agent. This study reports an unusual protein with germin-like structure, lacking typical oxalate oxidase activity. Instead, the proteolytic activity observed suggests that the protein is a cysteine peptidase. These structural peculiarities make Peruvianin­I an interesting model for further understanding of the action of laticifer fluids in plant defense.

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Klippel-Trenaunay syndrome (KTS) is a congenital disorder characterized by venous malformations and a predisposition to pulmonary embolism. We reviewed the imaging findings of 7 adult patients with KTS who underwent thoracic CT. While the superficial manifestations of KTS predominantly affect the extremities, patients frequently develop abnormalities of the pulmonary arterial system, particularly chronic thromboembolic pulmonary hypertension. Additionally, some patients are seen to develop pulmonary arteriolar aneurysms; the physiologic significance of this finding is unknown at this time. Radiologists should be aware of these potential findings and have a high index of suspicion for chronic PE in patients with KTS.

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MAIN CONCLUSION: The latex from Thevetia peruviana is rich in plant defense proteins, including a 120 kDa cysteine peptidase with structural characteristics similar to germin-like proteins. More than 20,000 plant species produce latex, including Apocynaceae, Sapotaceae, Papaveraceae and Euphorbiaceae. To better understand the physiological role played by latex fluids, a proteomic analysis of Thevetia peruviana (Pers.) Schum latex was performed using two-dimensional gel electrophoresis and mass spectrometry. A total of 33 proteins (86 %) were identified, including storage proteins, a peptidase inhibitor, cysteine peptidases, peroxidases and osmotins. An unusual cysteine peptidase, termed peruvianin-I, was purified from the latex by a single chromatographic step involving gel filtration. The enzyme (glycoprotein) was inhibited by E-64 and iodoacetamide and exhibited high specific activity towards azocasein (K m 17.6 µM), with an optimal pH and temperature of 5.0-6.0 and 25-37 °C, respectively. Gel filtration chromatography, two-dimensional gel electrophoresis, and mass spectrometry revealed that peruvianin-I possesses 120 kDa, pI 4.0, and six subunits (20 kDa). A unique N-terminal amino acid sequence was obtained to oligomer and monomers of peruvianin-I (1ADPGPLQDFCLADLNSPLFINGYPCRNPALAISDDF36). High-resolution images from atomic force microscopy showed the homohexameric structure of peruvianin-I may be organized as a trimer of dimers that form a central channel similar to germin-like proteins. Peruvianin-I exhibited no oxalate oxidase and superoxide dismutase activity or antifungal effects. Peruvianin-I represents the first germin-like protein (GLP) with cysteine peptidase activity, an activity unknown in the GLP family so far.

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BACKGROUND: African-Caribbean men, particularly Jamaican men, have one of the highest incidences of prostate cancer in the world. This cross-sectional study was conducted to investigate knowledge, attitudes, practices and factors associated with prostate cancer screening among men in western Jamaica. METHODS: A questionnaire was administered to men 40-93 years old during May to August 2007. The outcome variable of interest was previous prostate cancer screening. RESULTS: Approximately 35% of men were previously screened for prostate cancer. Men > 70 years were 93% less likely to be screened compared to men 40-49 years (95% CI: 0.01, 0.56). Men living in the parish of Trelawny were 10.5 times more likely not to be screened compared to men in St James (95% CI: 2.33, 47.17) and manual labourers were 5.5 times less likely to have been screened than non-manual labourers (95% CI: 0.97, 31.68). Men who had not been advised to have prostate cancer screening were 92% less likely to be screened than those advised (95% CI: 0.02, 0.29), and men who were not sure of how frequently screening should be conducted were 6.1 times more likely not to be screened compared to those who knew that screening should be conducted annually (95% CI: 1.10, 33.35). Men who visit healthcare providers only when they feel sick were 6.4 times more likely not to be screened compared to men who visit annually (95% CI: 1.63, 25.41). CONCLUSION: A substantial proportion of Jamaican men ≥ 40 years had never been screened for prostate cancer. Interventions should be instituted to make prostate cancer screening readily available and to promote active participation of men in these programmes especially men ≥ 70 years, men with less economic resources, and men who do not routinely visit a physician or health facility.

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Anthocyanins are of interest to the food industry because of their antioxidant power, attractive color, and stability in high acid foods. Powder from the Peruvian berry Berberis boliviana Lechler, rich in nonacylated anthocyanins (7% to 8% dry weight), was incorporated into yogurt samples containing 3 different fat levels. Color (CIE L, a, b, chroma, and hue angle), pigment (monomeric anthocyanin and polymeric color), and total phenolics were monitored over 8 wk of storage and compared to yogurt treatments containing purple carrot acylated anthocyanins, red beet betalaines, or FD&C Red nr 40. Anthocyanin profiles were analyzed by HPLC coupled to photodiode array and mass detectors. Color of yogurt containing B. boliviana anthocyanins at 20 mg cyanidin-3-glucoside (cy-3-glu) equivalents/100 g yogurt (L*= 65, chroma = 14, and hue angle = 335 degrees ) was similar to commercial blueberry yogurt (L*= 65, chroma = 10.5, and hue angle = 341 degrees ). High color, pigment, and phenolic stability were observed in yogurts colored with B. boliviana, independent of the fat matrix. Acylated anthocyanins from purple carrot extracts exhibited increased stability with higher fat content. Anthocyanin degradation followed 1st-order kinetics. Pigment half-lives were 125 and 104 d for nonacylated anthocyanins at 10 and 20 mg cy-3-glu equivalents/100 g yogurt and 550.2, 232.6, and 128.9 d for acylated anthocyanins at 20 mg of cy-3-glu equivalents/100 g of 4%, 2%, and 0% fat yogurt. Addition of B. boliviana whole berry powder to yogurt matrices produced an attractive, stable anthocyanin-rich product, eliminating the need for industrial colorant extraction.

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The M(w) = 8.3 deep (636 kilometers) Bolivian earthquake of 9 June 1994 was the largest deep-focus earthquake ever recorded. Seismic data from permanent stations plus portable instruments in South America show that rupture occurred on a horizontal plane and extended at least 30 by 50 kilometers. Rupture proceeded at 1 to 3 kilometers per second along the down-dip azimuth of the slab and penetrated through more than a third of the slab thickness. This extent is more than three times that expected for a metastable wedge of olivine at the core of the slab, and thus appears to be incompatible with an origin by transformational faulting. These large events may instead represent slip on preserved zones of weakness established in oceanic lithosphere at the Earth's surface.

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The observed joint distribution of births and child deaths for a cohort of women at a given point in time depends on the number of children that would have been born had the family experienced no deaths, the number of child deaths experienced, and the proportion of these deaths that are replaced by a subsequent birth. In this paper we estimate the parameters of the assumed distributions of these three events using a minimum distance estimation model and data from the 1970 Brazilian census. The parameter estimates are shown to be similar to those obtained previously using a maximum likelihood estimation model. When the data are subdivided according to women's years of schooling, estimates of probability of a child death and mean and variance of children born if no deaths decrease while estimates of probability of replacement of a dead child increase as years of schooling increase.

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