A comprehensive new inventory of Brazilian plants and fungi was published just in time to meet a 2010 Convention on Biological Diversity target and offers important insights into this biodiversity's ...global significance. Brazil is the home to the world's richest flora (40,989 species; 18,932 endemic) and includes two of the hottest hotspots: Mata Atlântica (19,355 species) and Cerrado (12,669 species). Although the total number of known species is one-third lower than previous estimates, the absolute number of endemic vascular plant species is higher than was previously estimated, and the proportion of endemism (56%) is the highest in the Neotropics. This compilation serves not merely to quantify the scale of the challenge faced in conserving Brazil's unique flora but also serves as a key resource to direct action and monitor progress. Similar efforts by other megadiverse countries are urgently required if the 2020 targets of the Convention on Biological Diversity and the Global Strategy for Plant Conservation are to be attained.
Several lines of evidence suggest that nitrogen in most tropical forests is relatively more available than N in most temperate forests, and even that it may function as an excess nutrient in many ...tropical forests. If this is correct, tropical forests should have more open N cycles than temperate forests, with both inputs and outputs of N large relative to N cycling within systems. Consequent differences in both the magnitude and the pathways of N loss imply that tropical forests should in general be more 15N enriched than are most temperate forests. In order to test this hypothesis, we compared the nitrogen stable isotopic composition of tree leaves and soils from a variety of tropical and temperate forests. Foliar δ 15N values from tropical forests averaged 6.5‰ higher than from temperate forests. Within the tropics, ecosystems with relatively low N availability (montane forests, forests on sandy soils) were significantly more depleted in 15N than other tropical forests. The average δ 15N values for tropical forest soils, either for surface or for depth samples, were almost 8‰ higher than temperate forest soils. These results provide another line of evidence that N is relatively abundant in many tropical forest ecosystems.
Summary
Background
The considerable genetic predisposition to deep vein thrombosis (DVT) is only partially accounted for by known genetic risk variants. Rare single‐nucleotide variants (SNVs) of the ...coding areas of hemostatic genes may explain part of this missing heritability. The ADAMTS13 and VWF genes encode two interconnected proteins with fundamental hemostatic functions, the disruption of which may result in thrombosis.
Objectives
To study the distribution and burden of rare coding SNVs of ADAMTS13 and VWF found by sequencing in cases and controls of DVT.
Patients/Methods
The protein‐coding areas of 186 hemostatic/proinflammatory genes were sequenced by next‐generation technology in 94 thrombophilia‐negative patients with DVT and 98 controls. Gene‐specific information on ADAMTS13 and VWF was used to study the association between DVT and rare coding SNVs of the two genes.
Results
More than 70 billion base pairs of raw sequence data were produced to sequence the 700‐kb target area with a median redundancy of × 45 in 192 individuals. Most of the 4366 SNVs identified were rare and non‐synonymous, indicating pathogenetic potential. Rare (frequency of < 1%) and low‐frequency (< 5%) coding SNVs of ADAMTS13 were associated with DVT (prevalence 17% vs. 4%; odds ratio OR 4.8 and 95% confidence interval CI 1.6–15.0 for rare coding; prevalence 36% vs. 23%, OR 1.9 and 95% CI 1.0–3.5 for low‐frequency coding). Patients with rare coding SNVs of ADAMTS13 had lower plasma levels of ADAMTS‐13 activity than patients without them. SNVs of VWF were not associated with DVT.
Conclusions
We found an excess of rare coding SNVs of the ADAMTS13 gene in patients with DVT.
As the mechanisms leading to the persistence of hepatitis B virus (HBV) infection are poorly understood and as the histocompatibility leucocyte antigen (HLA)‐G is well described as a tolerogenic ...molecule, we evaluated HLA‐G expression in 74 specimens of HBV liver biopsies and in 10 specimens obtained from previously healthy cadaver liver donors. HBV specimens were reviewed and classified by the METAVIR score, and HLA‐G expression was assessed by immunohistochemistry. No HLA‐G expression was observed in control hepatocytes. In contrast, 57 (77%) of 74 HBV specimens showed soluble and membrane‐bound HLA‐G expression in hepatocytes, biliary epithelial cells or both. No associations between the intensity of HLA‐G expression and patient age or gender, HBeAg status, severity of liver fibrosis, and grade of histological findings were observed. Although significance was not reached (P = 0.180), patients exhibiting HLA‐G expression presented a higher median HBV DNA viral load (105 copies/mL) than those who did not express HLA‐G (103.7 copies/mL). These results indicate that HLA‐G is expressed in most cases of chronic HBV infection in all stages and may play a role in the persistency of HBV infection.
The HFE molecule controls iron uptake from gut, and defects in the molecule have been associated with iron overload, particularly in hereditary hemochromatosis. The HFE gene including both coding and ...boundary intronic regions were sequenced in 304 Brazilian individuals, encompassing healthy individuals and patients exhibiting hereditary or acquired iron overload. Six sites of variation were detected: (1) H63D C>G in exon 2, (2) IVS2 (+4) T>C in intron 2, (3) a C>G transversion in intron 3, (4) C282Y G>A in exon 4, (5) IVS4 (−44) T>C in intron 4, and (6) a new guanine deletion (G>del) in intron 5, which were used for haplotype inference. Nine HFE alleles were detected and six of these were officially named on the basis of the HLA Nomenclature, defined by the World Health Organization (WHO) Nomenclature Committee for Factors of the HLA System, and published via the IPD‐IMGT/HLA website. Four alleles, HFE*001, *002, *003, and *004 exhibited variation within their exon sequences.
The influences of different kinds of anthropogenic activities on rainwater chemistry in a tropical area were studied during one uninterrupted year at Piracicaba River Basin (Southeast Brazil). A ...total of 272 rainwater samples collected continuously from August 1997 to July 1998 at four different sites were analyzed for F
−, CH
3COO
−, HCOO
−, MSA, Cl
−, NO
2
−, Br
−, NO
3
−, SO
4
2−, C
2O
4
2−, PO
4
3−, Na
+, NH
4
+, K
+, Mg
2+, Ca
2+, DOC (dissolved organic carbon), DIC (dissolved inorganic carbon), pH and conductivity. The most abundant ion was H
+ and rain acidity was significant at all sampling sites (average pH of 4.4–4.5). The sources of this free acidity differ among sites and appear to be correlated to the different land-uses. The composition of rainwater appeared to be controlled mostly by three sources: soil dust, sugar cane burning and industrial emissions.
Background/Objectives: Vitamin A deficiency (VAD) is a major public health problem. The supplementation of lactating women could be an effective strategy to combat it. The objective of this study was ...to assess the impact of maternal vitamin A supplementation on the mother–infant pair. Subjects/Methods: This was a double blind, placebo-controlled randomized clinical assay in which 33 women received 200 000 IU of vitamin A and 33 women received soy oil between 20th and 30th postpartum days. Maternal blood and milk samples were collected immediately before supplementation and 3 months after delivery, when blood was also collected from the babies. Retinol concentrations 0.70 μmol/l in serum and 1.05 μmol/l in milk were considered to indicate VAD. Results: Increase in serum retinol level was observed in the supplemented group compared with the pre-supplementation levels (1.05 and 1.17 μmol/l, respectively; P=0.026) and to the post-supplementation levels of the control group (1.02 μmol/l; P=0.032). Reduction in breast milk retinol was observed in the control group compared with the pre-supplementation levels (1.93 and 1.34 μmol/l, respectively; P<0.0001) and to the post-supplementation levels of the supplemented group (1.56 μmol/l; P=0.0003). There was significant difference in the prevalence of VAD in breast milk after supplementation, 55.6% (15/27) in the control group and 16.1% (5/31) in the supplemented group (P=0.002). VAD was present in 66.1% (39/59) of infants, with mean serum retinol levels of 0.64±0.30 μmol/l in the control group and of 0.69±0.26 μmol/l in the supplemented group. Conclusions: Supplementation had a positive impact on maternal vitamin A status. No effect on infant status was detectable 2 months after supplementation with a single dose.
The carbon and nitrogen isotopic compositions of aerosol particles collected in the Piracicaba region, where C4 plants like sugarcane and pasture dominate the land cover, were measured. For ...comparison, aerosol particles were also analyzed from the Santarém region, Amazon basin, where the main land cover is primary forest. The average
δ
13C value of samples collected in Piracicaba was equal to −20.9±0.8‰. The average
δ
13C of samples collected in Santarém was almost 5‰ smaller than in Piracicaba (−25.8±0.5‰). This difference between the two sites was attributed to the presence of C4 material in Piracicaba aerosol particles. On the other hand, there was no statistical difference between the average
δ
15N values observed in Piracicaba (10.6±2.8‰) and Santarém (11.5±2.1‰). The
δ
13C and
δ
15N values of aerosol particles collected in Santarém were higher than vegetation tissues and soil organic matter, which are the potential sources of organic matter to aerosol particles.
Abstract
We present a measurement of the cosmic-ray spectrum above 100 PeV using the part of the surface detector of the Pierre Auger Observatory that has a spacing of 750 m. An inflection of the ...spectrum is observed, confirming the presence of the so-called
second-knee
feature. The spectrum is then combined with that of the 1500 m array to produce a single measurement of the flux, linking this spectral feature with the three additional breaks at the highest energies. The combined spectrum, with an energy scale set calorimetrically via fluorescence telescopes and using a single detector type, results in the most statistically and systematically precise measurement of spectral breaks yet obtained. These measurements are critical for furthering our understanding of the highest energy cosmic rays.
Background/Objectives: Vitamin A deficiency (VAD) is a world public health problem contributing to the increase in childhood morbidity and mortality in developing countries and severe deficiency of ...vitamin A may lead to xerophthalmia and blindness. The objective of this study was to determine the prevalence of VAD among Brazilian school-aged children attended at a primary health unit and to verify if some considered risk factor was associated with VAD in this group. Subjects/Methods: A descriptive prospective transverse study was conducted on 103 randomly selected children. A total of 54 boys and 49 girls aged 5.5-11 years had the relative dose-response (RDR) test performed on. Possible ocular alterations related to vitamin A and the status of anemia, serum zinc, some acute-phase proteins, and anthropometric situation were determinate by an analytic design. Results: No child presented xerophthalmia. Serum retinol values lower than 1.05 and 0.7 mol l-1, respectively were found in 26.2 and 5.8% of the children. The prevalence of hypovitaminosis detected by RDR test was 20.4%. The following variables and their relationship with VAD were evaluated: sex (P=0.33; 95% confidence interval 0.61-4.34), weight and height (P0.5), hemoglobin (P=0.15), C-reactive protein (P=0.56; 95% confidence interval 0.75-18.26), -1-acid-glycoprotein (P=0.56; 95% confidence interval 0.15-15.42) and serum zinc (P=0.31). None of these variables was related to VAD. Conclusions: In this population, the prevalence of VAD detected could be considered a public health problem. School-aged children can be considered at risk for VAD mainly of a subclinical level, even without some associated risk factors.
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