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51.
Christian Loret de Mola Luciana de Avila Quevedo Ricardo Tavares Pinheiro Helen Gon?alves Denise Petrucci Gigante Janaína Vieira dos Santos Motta Fernando C. Barros Bernardo Lessa Horta 《PloS one》2015,10(10)
Background
Poor nutrition and growth during fetal life and childhood might be associated with depression in adulthood; however, studies evaluating these associations present controversial results, especially when comparing studies using different proxies for fetal growth. We evaluated the association of fetal and childhood growth/nutrition with depression, in adulthood, using different approaches and measurement methods.Method
In 1982, hospital births (n = 5914) in Pelotas, southern Brazil, were examined and have been prospectively followed. At 30 years, the presence of major depression and depressive symptoms severity was evaluated using the Mini International Neuropsychiatric Interview (MINI) and Beck Depression Inventory (BDI-II). The present study assessed their association with birth weight, premature birth, small for gestational age (SGA), stunting and conditional growth during childhood.Results
At 30 years, 3576 individuals were evaluated and 7.9% had major depression. Low birth weight (PR = 1.01 95%CI [0.64–1.60]), having been born SGA (PR = 0.87 95%CI [0.64–1.19]) and premature birth (PR = 1.22 95%CI [0.72–2.07]) were not associated with major depression in multivariable models. However, those born SGA who were also stunted in childhood had a higher prevalence of major depression (PR = 1.87 95%CI [1.06–3.29]) and greater odds of scoring a higher level of depression in the BDI-II (OR = 2.18 95%CI [1.34–3.53]).Conclusion
In this Brazilian cohort of young adults, those born SGA who were also stunted during childhood had a higher risk of depression in adulthood. Our results show that the effect of growth impairment on depression is cumulative. 相似文献52.
Lead plays an important role in many industrial processes. Although highly useful to man, lead has various types of toxic effects. There is constantly growing evidence of a relationship between the induction of chromosome breaks and an increased risk of onset of cancer. However, available data about the possible genotoxic and carcinogenic action of lead are conflicting. In this report we present the results of studies on lead concentrations in blood and the respective micronucleus frequencies in peripheral blood lymphocytes from workers employed in the recycling of automotive batteries in the surroundings of Porto Alegre, Brazil. We observed that in the occupationally exposed group, both lead concentration in peripheral blood and micronucleus frequency in lymphocytes were significantly higher compared to control (Z=6.35, P<0.0001 and Z=4.47, P<0.0001). The nuclear division index (NDI) values were significantly higher in the control group than in the exposed group (Z=2.13, P=0.0330), indicating a possible effect of Pb on nuclear proliferation. We also detected a negative correlation between micronuclei and progression of nuclear division (tau=-0.312, P=0.0129). There were no changes in micronucleus frequency between smoking and non-smoking workers exposed to lead (Z=0.03, P=0.9790). The only difference found between the groups of smokers and non-smokers was with respect to NDI, whose values were significantly higher among non-smokers (Z=1.98, P=0.0481). 相似文献
53.
Alberto Busilacchi Antonio Gigante Monica Mattioli-Belmonte Sandra Manzotti Riccardo A.A. Muzzarelli 《Carbohydrate polymers》2013
The idea of using chitosan as a functional delivery aid to support simultaneously PRP, stem cells and growth factors (GF) is associated with the intention to use morphogenic biomaterials to modulate the natural healing sequence in bone and other tissues. For example, chitosan–chondroitin sulfate loaded with platelet lysate was included in a poly(d,l-lactate) foam that was then seeded with human adipose-derived stem cells and cultured in vitro under osteogenic stimulus: the platelet lysate provided to the bone tissue the most suitable assortment of GF which induces the osteogenic differentiation of the mesenchymal stem cells. PDGF, FGF, IGF and TGF-β were protagonists in the repair of callus fractures. The release of GF from the composites of chitosan–PRP and either nano-hydroxyapatite or tricalcium phosphate was highly beneficial for enhancing MSC proliferation and differentiation, thus qualifying chitosan as an excellent vehicle. A number of biochemical characteristics of chitosan exert synergism with stem cells in the regeneration of soft tissues. 相似文献
54.
Thurow HS Haack R Hartwig FP Oliveira IO Dellagostin OA Gigante DP Horta BL Collares T Seixas FK 《Journal of biosciences》2011,36(5):823-831
Arg72Pro SNP of p53 has been associated with many types of cancer as well as with survival and longevity. We evaluated the
Arg72Pro SNP frequencies of a Brazilian birth cohort and their association with current, demographic and birth epidemiological
parameters available. In 1982, all hospital births of Pelotas, southern Brazil, were identified and studied prospectively.
In 2004–5, blood samples were collected and DNA extracted. PCR-RFLP was used to genotype the Arg72Pro SNP in 3794 individual
samples of the Brazil birth cohort and DNA sequencing was performed to confirm the genotypes. The genotype distribution, which
was in Hardy–Weinberg equilibrium, showed a predominance of the arginine amino acid with a frequency of 46.9% Arg/Arg, 42.2%
Arg/Pro and 10.9% Pro/Pro. The allele frequency was 0.68 of Arginine and 0.32 of Proline. The Arg72Pro SNP genotype and allelic
frequency were related to skin colour where proline amino acid was observed more among black subjects, while arginine amino
acid was observed more among white subjects. The individuals without family history of cancer and those with low birth weight
were associated with arginine amino acid. The Arg72Pro SNP was strongly associated with important epidemiological variables
confirming that genetic profiles on cohort studies can improve our understanding of the susceptibility of diseases and its
risk factors. 相似文献
55.
Localization of acetylcholine receptors and synaptic ultrastructure at nerve-muscle contacts in culture: dependence on nerve type 总被引:1,自引:6,他引:1 下载免费PDF全文
In cultures of xenopus myotomal muscle cells and spinal cord (SC) some of the nerve-muscle contacts exhibit a high density of acetylcholine receptors (AchRs [Anderson et al., 1977, J. Physiol. (Lond.). 268:731- 756,757-773]) and synaptic ultrastructure (Weldon and Cohen, 1979, J. Neurocytol. 8:239-259). We have examined whether similarly specialized contacts are established when the muscle cells are cultured with explants of xenopus dorsal root ganglia (DRG) or sympathetic ganglia (SG). The outgrowth from the ganglionic explants contained neuronal and non- neuronal cell processes. Although both types of processes approached within 100 A of muscle cells, synaptic ultrastructure was rarely observed at these contacts. Because patches of postsynaptic ultrastructure also develop on noncontacted muscle cells, the very few examples of contacts with such specializations probably occurred by chance. AChRs were stained with fluroscent α-bungarotoxin. More than 70 percent of the SC-contacted muscle cells exhibited a high receptor density along the path of contact. The corresponding values for DRG- and SG- contacted muscle cells were 10 and 6 percent. Similar values were obtained when the ganlionic and SC explants were cultured together in the same chamber. The few examples of high receptor density at ganglionic-muscle contacts resembled the characteristic receptor patches of noncontacted muscle cells rather than the narrow bands of high receptor density seen at SC-muscle contacts. In addition, more than 90 percent of these ganglionic- contacted muscle cells had receptor patches elsewhere, compared to less than 40 percent for the SC-contacted muscle cells. These findings indicate that the SC neurites possess a specific property which is important for the establishment of synaptically specialized contacts with muscle and that this property is lacking in the DRG and SG neurites. 相似文献
56.
Luísa Gigante Carvalheiro William E. Kunin Petr Keil Jesus Aguirre‐Gutiérrez Willem Nicolaas Ellis Richard Fox Quentin Groom Stephan Hennekens Wouter Van Landuyt Dirk Maes Frank Van de Meutter Denis Michez Pierre Rasmont Baudewijn Ode Simon Geoffrey Potts Menno Reemer Stuart Paul Masson Roberts Joop Schaminée Michiel F. WallisDeVries Jacobus Christiaan Biesmeijer 《Ecology letters》2013,16(7):870-878
Concern about biodiversity loss has led to increased public investment in conservation. Whereas there is a widespread perception that such initiatives have been unsuccessful, there are few quantitative tests of this perception. Here, we evaluate whether rates of biodiversity change have altered in recent decades in three European countries (Great Britain, Netherlands and Belgium) for plants and flower visiting insects. We compared four 20‐year periods, comparing periods of rapid land‐use intensification and natural habitat loss (1930–1990) with a period of increased conservation investment (post‐1990). We found that extensive species richness loss and biotic homogenisation occurred before 1990, whereas these negative trends became substantially less accentuated during recent decades, being partially reversed for certain taxa (e.g. bees in Great Britain and Netherlands). These results highlight the potential to maintain or even restore current species assemblages (which despite past extinctions are still of great conservation value), at least in regions where large‐scale land‐use intensification and natural habitat loss has ceased. 相似文献
57.
Fish is a very important part of the human diet in Amazonia. Near the growing cities, fish populations and individual size have decreased over the past decades. Alternatives to traditional and industrial fishing arise, including fish farming. Strategies to minimize the impact of fish farms on the environment are needed to have a regular and healthy fish supply. This is to avoid a reduction of biodiversity, a depletion of natural resources, and/or the induction of significant changes in the structure and functioning of adjacent ecosystems. Very little research has been performed on management of effluents as to maintain the quality of water resources. The present study aimed at testing the efficiency of the Amazonian aquatic macrophyte Eichhornia crassipes as a biofilter for the treatment of effluents from fish farming. In three filtering treatments (50%, 75% and 100% plant cover) and a control (0%), physical and chemical properties of the water were measured and analyzed in a nursery with fish after passing the biofilter system, with a hydraulic retention time of 24 hours. The analyzed variables showed no significant differences (p>0.05) among the treatments with 50-100% cover, indicating that 50% cover would be enough for a good efficiency of the biofilter. All parameters were reduced after passage of the biofilter under the presence of E. crassipes: 73.7% for electrical conductivity, 15% for pH, 84.5% for turbidity, 86.8% for nitrite, 69% for total phosphorus, and 77.8% for orthophosphate. The concentrations of total nitrogen, nitrate and ammonium ions were not significantly changed (p>0.05). We conclude that E. crassipes is effective in improving the quality of effluents from fish farming, with less efficiency for nitrogen compounds. Our treatment system can be adopted by small and medium-sized farmers, aiming at a sustainable employment of the activity. 相似文献
58.
Gigante A Manzotti S Bevilacqua C Orciani M Di Primio R Mattioli-Belmonte M 《European journal of histochemistry : EJH》2008,52(3):169-174
Bone marrow is a useful cell source for skeletal tissue engineering approaches. In vitro differentiation of marrow mesenchymal stem cells (MSCs) to chondrocytes or osteoblasts can be induced by the addition of specific growth factors to the medium. The present study evaluated the behaviour of human MSCs cultured on various scaffolds to determine whether their differentiation can be induced by cell-matrix interactions. MSCs from bone marrow collected from the acetabulum during hip arthroplasty procedures were isolated by cell sorting, expanded and characterised by a flow cytometry system. Cells were grown on three different scaffolds (type I collagen, type I + II collagen and type I collagen + hydroxyapatite membranes) and analysed by histochemistry, immunohistochemistry and spectrophotometry (cell proliferation, alkaline phosphatase activity) at 15 and 30 days. Widely variable cell adhesion and proliferation was observed on the three scaffolds. MSCs grown on type I+II collagen differentiated to cells expressing chondrocyte markers, while those grown on type I collagen + hydroxyapatite differentiated into osteoblast-like cells. The study highlighted that human MSCs grown on different scaffold matrices may display different behaviours in terms of cell proliferation and phenotype expression without growth factor supplementation. 相似文献
59.
GV Pavlova AA Vergun EY Rybalkina PR Butovskaya AP Ryskov 《Cell cycle (Georgetown, Tex.)》2015,14(2):200-205
Random amplified polymorphic DNA (RAPD) analysis was adapted for genomic identification of cell cultures and evaluation of DNA stability in cells of different origin at different culture passages. DNA stability was observed in cultures after no more than 5 passages. Adipose-derived stromal cells demonstrated increased DNA instability. RAPD fragments from different cell lines after different number of passages were cloned and sequenced. The chromosomal localization of these fragments was identified and single-nucleotide variations in RAPD fragments isolated from cell lines after 8–12 passages were revealed. Some of them had permanent localization, while most variations demonstrated random distribution and can be considered as de novo mutations. 相似文献
60.
Ivana Antonucci Irene Iezzi Elisena Morizio Filiberto Mastrangelo Andrea Pantalone Monica Mattioli-Belmonte Antonio Gigante Vincenzo Salini Giuseppe Calabrese Stefano Tetè Giandomenico Palka Liborio Stuppia 《BMC biotechnology》2009,9(1):1-7