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1.
Philos Trans R Soc Lond B Biol Sci ; 375(1810): 20190513, 2020 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-32892733

RESUMO

During the summer of 2018, a widespread drought developed over Northern and Central Europe. The increase in temperature and the reduction of soil moisture have influenced carbon dioxide (CO2) exchange between the atmosphere and terrestrial ecosystems in various ways, such as a reduction of photosynthesis, changes in ecosystem respiration, or allowing more frequent fires. In this study, we characterize the resulting perturbation of the atmospheric CO2 seasonal cycles. 2018 has a good coverage of European regions affected by drought, allowing the investigation of how ecosystem flux anomalies impacted spatial CO2 gradients between stations. This density of stations is unprecedented compared to previous drought events in 2003 and 2015, particularly thanks to the deployment of the Integrated Carbon Observation System (ICOS) network of atmospheric greenhouse gas monitoring stations in recent years. Seasonal CO2 cycles from 48 European stations were available for 2017 and 2018. Earlier data were retrieved for comparison from international databases or national networks. Here, we show that the usual summer minimum in CO2 due to the surface carbon uptake was reduced by 1.4 ppm in 2018 for the 10 stations located in the area most affected by the temperature anomaly, mostly in Northern Europe. Notwithstanding, the CO2 transition phases before and after July were slower in 2018 compared to 2017, suggesting an extension of the growing season, with either continued CO2 uptake by photosynthesis and/or a reduction in respiration driven by the depletion of substrate for respiration inherited from the previous months due to the drought. For stations with sufficiently long time series, the CO2 anomaly observed in 2018 was compared to previous European droughts in 2003 and 2015. Considering the areas most affected by the temperature anomalies, we found a higher CO2 anomaly in 2003 (+3 ppm averaged over 4 sites), and a smaller anomaly in 2015 (+1 ppm averaged over 11 sites) compared to 2018. This article is part of the theme issue 'Impacts of the 2018 severe drought and heatwave in Europe: from site to continental scale'.


Assuntos
Atmosfera/análise , Ciclo do Carbono , Dióxido de Carbono/análise , Secas , Ecossistema , Europa (Continente)
3.
Maturitas ; 69(1): 91-3, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21429677

RESUMO

The 'stem cell burden' hypothesis represents a plausible explanation for the association between birth-weight and the risk of breast cancer in adulthood. The size of the overall stem cell pool would be expected to affect organ size and consequently birth-weight, making birth-weight a proxy for the overall number of fetal stem cells. As stem cells are self-renewing, the greater their number is at birth, the higher will be the chance that one of them will undergo carcinogenesis over the years. To investigate the correlation between birth-weight and stem cell burden, we examined the cord blood hematopoietic CD34+ stem cell population as an indicator of the overall fetal stem cell number. We measured both the CD34+ level (by flow cytometry) and the CD34+ proliferative potential (by the GM-CFU culture), in a sample of 1037 healthy newborn cord blood donors. We found that heavier babies had a significantly greater CD34+ stem cell concentration (p<0.001) and a higher GM-CFU number than lighter babies (p<0.001). Thus, a high birth-weight was positively associated with a high concentration of CD34+ stem cells and also with a qualitatively higher "stemness" of this pool. Therefore, our data support the theory that birth-weight reflects the number of fetal stem cells.


Assuntos
Antígenos CD34 , Peso ao Nascer , Sangue Fetal/citologia , Células-Tronco Fetais/metabolismo , Células-Tronco Hematopoéticas/metabolismo , Neoplasias/etiologia , Adulto , Proliferação de Células , Feminino , Citometria de Fluxo , Células Progenitoras de Granulócitos e Macrófagos/metabolismo , Humanos , Recém-Nascido , Masculino , Neoplasias/metabolismo , Tamanho do Órgão , Fatores de Risco
5.
Tissue Antigens ; 74(2): 156-63, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19500315

RESUMO

Birth weight is known to be a direct indicator of perinatal mortality and a clear predictor of adult pathologies too. It has been correlated with several causes of mortality in adulthood: low birth weight with diabetes, nephropathy and cardiovascular diseases and high birth weight with autoimmune diseases and cancer. In genome-wide studies, an extended human leucocyte antigen (HLA) region has been linked to birth weight variation. We focused our attention on the HLA haplotypes marked by HLA-A, HLA-B and HLA-DRB1 polymorphisms in 1206 healthy Caucasian newborns belonging to the Cord Blood Bank of Pavia (Italy) and their mothers, aiming to investigate the association between this restricted HLA region and birth weight variation. In our study, the HLA-B*38;DRB1*13 haplotype showed an ascending trend among centiles addressing to the high foetal weight. The HLA-A*02;B*15 haplotype showed a descending trend among centiles addressing to the low foetal weight. Besides the acknowledged correlation between the HLA-A*02 and HLA-B*15 alleles (as well as low birth weight) and type I diabetes and between the HLA-B*38 and HLA-DRB1*13 alleles (as well as high birth weight) and several autoimmune diseases, we cannot predict if our babies, healthy at birth, will suffer from these pathologies during life. Nevertheless, our data point to the HLA telomeric end for markers linked to the low birth weight and to the HLA centromeric end for markers linked to the high birth weight, thus limiting the region involved in birth weight variation, which still represents a useful predictor of disease risk in adulthood.


Assuntos
Peso ao Nascer/genética , Crescimento e Desenvolvimento/genética , Antígenos HLA/genética , Estudos de Coortes , Feminino , Previsões , Haplótipos , Humanos , Recém-Nascido , Masculino , Distribuição Normal , Polimorfismo Genético , Gravidez
6.
Environ Pollut ; 150(1): 125-39, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17604887

RESUMO

Recent research in nitrogen exchange with the atmosphere has separated research communities according to N form. The integrated perspective needed to quantify the net effect of N on greenhouse-gas balance is being addressed by the NitroEurope Integrated Project (NEU). Recent advances have depended on improved methodologies, while ongoing challenges include gas-aerosol interactions, organic nitrogen and N(2) fluxes. The NEU strategy applies a 3-tier Flux Network together with a Manipulation Network of global-change experiments, linked by common protocols to facilitate model application. Substantial progress has been made in modelling N fluxes, especially for N(2)O, NO and bi-directional NH(3) exchange. Landscape analysis represents an emerging challenge to address the spatial interactions between farms, fields, ecosystems, catchments and air dispersion/deposition. European up-scaling of N fluxes is highly uncertain and a key priority is for better data on agricultural practices. Finally, attention is needed to develop N flux verification procedures to assess compliance with international protocols.


Assuntos
Poluentes Atmosféricos/química , Efeito Estufa , Modelos Químicos , Compostos de Nitrogênio/química , Poluentes Atmosféricos/análise , Atmosfera , Ecossistema , Monitoramento Ambiental/métodos , Europa (Continente) , Compostos de Nitrogênio/análise
7.
Stem Cells Dev ; 13(4): 350-6, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15345128

RESUMO

Immunomagnetic cell selection (ICS) of CD34(+) cells is increasingly adopted in allogeneic and autologous transplant settings. Because many variables can affect the final results of ICS, we focused our study toward the influence exerted by the leukapheresis (LKF) cell composition on recovery, purity, and log of T and B depletion of the immunoselected cells. A total of 39 consecutive CD34(+) ICS were performed with the Isolex 300i (Baxter) device on 39 LKF from 9 HLA haploidentical donors and 20 patients. Flow cytometric analysis was performed both on the leukapheresis content and on the immunoselected cells. The statistical analysis was performed utilizing the Pearson's correlation test and the Mann-Whitney U test. The median purity and recovery of the immunoselected CD34(+) cells were 95.3% (IR: 93.0-99.0) and 55.1% (IR: 41.8-68.2), respectively. The median log of T and B depletion were 3.87 (IR: 3.5-4.3) and 2.9 (IR: 2.5-3.5), respectively. Our data indicate that not only the CD34(+) cell load but also the ratio among the cells belonging to the starting fraction can influence the results of ICS. LKF collection protocols have to be addressed to collect an high number of CD34(+) cells (>500 x 10(6)) without taking care of the contaminating cells when the Baxter Isolex 300i device is employed.


Assuntos
Leucaférese/métodos , Leucócitos/citologia , Adolescente , Adulto , Antígenos CD/sangue , Antígenos CD34/sangue , Artrite Reumatoide/terapia , Linfócitos B/citologia , Linfócitos B/imunologia , Criança , Pré-Escolar , Feminino , Mobilização de Células-Tronco Hematopoéticas , Doença de Hodgkin/terapia , Humanos , Separação Imunomagnética/instrumentação , Separação Imunomagnética/métodos , Leucemia Mielogênica Crônica BCR-ABL Positiva/terapia , Masculino , Pessoa de Meia-Idade , Mieloma Múltiplo/terapia , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , Análise de Regressão , Linfócitos T/citologia , Linfócitos T/imunologia
8.
Transfusion ; 41(10): 1299-305, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11606832

RESUMO

BACKGROUND: Extracorporeal photochemotherapy (EPC) has recently been proposed for the treatment of adults with either acute or chronic GVHD. However, data on children given this therapy are scarce. A Phase I-II study was carried out on EPC in children experiencing GVHD after allogeneic transplantation of HPCs. STUDY DESIGN AND METHODS: Nine patients with steroid-resistant, grade II-IV acute GVHD and 14 with chronic GVHD, all of whom had been refractory to at least one line of treatment, were enrolled in this study and analyzed. The median age was 10.3 years (range, 5.4-18.1), and the median body weight was 35 kg (range, 17-89). RESULTS: Seven of the nine patients with acute GVHD showed a response to EPC, whereas the disease progressed in the remaining two children (both with skin, gastrointestinal, and liver GVHD), and they died of grade IV acute GVHD. Among the seven children who responded to EPC, it was possible to completely discontinue immunosuppressive treatment in three. In the 14 children with chronic GVHD, 4 and 5 patients experienced complete and partial response to EPC, respectively, whereas the remaining 5 patients, all with extensive chronic GVHD, had stable disease or disease that progressed during EPC. Among these latter 5 patients, 3 died. In 6 of the 9 patients with chronic GVHD responding to EPC, immunosuppressive therapy was discontinued. CONCLUSION: EPC is safe, feasible, and effective in children with either acute or chronic GVHD occurring after an allograft.


Assuntos
Doença Enxerto-Hospedeiro/terapia , Fotoferese/normas , Doença Aguda , Adolescente , Criança , Pré-Escolar , Doença Crônica , Resistência a Medicamentos , Doença Enxerto-Hospedeiro/mortalidade , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Humanos , Estudos Prospectivos , Esteroides , Taxa de Sobrevida , Transplante Homólogo/efeitos adversos , Resultado do Tratamento
9.
Science ; 281(5376): 544-6, 1998 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-9677193

RESUMO

Atmospheric carbon monoxide (CO) exhibits mass-independent fractionation in the oxygen isotopes. An 17O excess up to 7.5 per mil was observed in summer at high northern latitudes. The major source of this puzzling fractionation in this important trace gas is its dominant atmospheric removal reaction, CO + OH --> CO2 + H, in which the surviving CO gains excess 17O. The occurrence of mass-independent fractionation in the reaction of CO with OH raises fundamental questions about kinetic processes. At the same time the effect is a useful marker for the degree to which CO in the atmosphere has been reacting with OH.

10.
Appl Opt ; 33(33): 7704-16, 1994 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-20962979

RESUMO

Measurements of (13)CH(4)/(12)CH(4) and (12)CH(3)D/(12)CH(4) ratios in atmospheric methane (CH(4)) sources provide important information about the global CH(4) budget as well as about CH(4) production and consumption processes occurring within the various sources. As an alternative to the conventional mass spectrometer (MS) technique, which requires conversion of CH(4) to CO(2) and H(2), we have developed a tunable diode laser absorption spectrometer (TDLAS), which permits rapid direct measurements of the (13)CH(4)/(12)CH(4) and (12)CH(3)D/(12)CH(4) ratios. An intercomparison between TDLAS and MS techniques for samples from natural wetlands, landfills, and natural gas sources resulted in a mean deviation of Δδ(13)C = 0.44‰ and ΔδD = 5.1‰. In the present system the minimum mixing ratios required are 50 parts in 10(6) by volume (ppmv) CH(4) (sample size 2 µmol CH(4)) for direct δ(13)C measurements and 2000 ppmv (sample size 80 µmol CH(4)) for direct δD measurements. These mixing-ratio limits are adequate for most CH(4) source characterization studies without requiring sample preconcentration.

11.
Haematologica ; 75(3): 220-3, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-2227617

RESUMO

Iron transport from the mother to the fetus is mediated by transferrin receptors located at the maternofetal interface of the placenta. Transferrin receptors bind iron-loaded transferrin molecules from the maternal plasma, thus allowing iron uptake by trophoblastic cells which then deliver the metal to the fetal plasma. We have measured the transferrin receptor content in the placentas from 16 normal-term pregnancies and investigated the relationships between transferrin receptor expression and non-haem iron content, as well as maternal and fetal iron status. Transferrin receptor content was evaluated indirectly by determining the transferrin binding capacity of a placenta extract. Transferrin receptor content of the placenta ranged from 20 to 154 micrograms/g of tissue, with a mean value of 96 +/- 37 micrograms/g. The mean non-haem iron content was 78 +/- 11 micrograms/g of tissue, corresponding to 47 +/- 10 mg for the whole placentas. The amount of transferrin receptors in the placenta was found to be inversely related to the amount of non-haem iron (r = 0.64; p less than 0.025). No significant relationship was observed between each of these two parameters and the iron status of either the mother or the fetus. We conclude that placental non-haem iron, which represents a storage form of this element, is likely to play a regulatory role in the expression of transferrin receptors, and consequently in the process of iron uptake by the placenta.


Assuntos
Placenta/metabolismo , Receptores da Transferrina/biossíntese , Feminino , Humanos , Gravidez
12.
Medicina (Firenze) ; 10(1): 31-2, 1990.
Artigo em Italiano | MEDLINE | ID: mdl-2381277

RESUMO

A case of primary biliary cirrhosis occurred during the first quarter of pregnancy in a 29-years-old primipara is described. Possible relationships with a former anti-hepatitis B vaccination and with positive familiarity reduction of IgA are discussed. Follow-up to the patient after two years therapy with colchicine 1 mg a day is also described.


Assuntos
Cirrose Hepática Biliar , Complicações na Gravidez , Adulto , Colchicina/uso terapêutico , Feminino , Seguimentos , Humanos , Cirrose Hepática Biliar/tratamento farmacológico , Gravidez , Complicações na Gravidez/tratamento farmacológico , Fatores de Tempo
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