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2.
Water Resour Res ; 58(11): e2021WR031721, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36582769

RESUMEN

The redistribution of biological (transpiration) and non-biological (interception loss, soil evaporation) fluxes of terrestrial evaporation via atmospheric circulation and precipitation is an important Earth system process. In vegetated ecosystems, transpiration dominates terrestrial evaporation and is thought to be crucial for regional moisture recycling and ecosystem functioning. However, the spatial and temporal variability in the dependency of precipitation on transpiration remains understudied, particularly in sparsely sampled regions like Africa. Here, we investigate how biological and non-biological sources of evaporation in Africa contribute to rainfall over the major watersheds in the continent. Our study is based on simulated atmospheric moisture trajectories derived from the Lagrangian model FLEXPART, driven by 1° resolution reanalysis data over 1981-2016. Using daily satellite-based fractions of transpiration over terrestrial evaporation, we isolate the contribution of vegetation to monthly rainfall. Furthermore, we highlight two watersheds (Congo and Senegal) for which we explore intra- and interannual variability of different precipitation sources, and where we find contrasting patterns of vegetation-sourced precipitation within and between years. Overall, our results show that almost 50% of the annual rainfall in Africa originates from transpiration, although the variability between watersheds is large (5%-68%). We conclude that, considering the current and projected patterns of land use change in Africa, a better understanding of the implications for continental-scale water availability is needed.

4.
J Visc Surg ; 159(3): 222-228, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35249858

RESUMEN

The French legislation on human subject research known as the Jardé law of 5th March 2012 has been applicable since November 2016. It concerns all research involving human subjects (RIPH, in French) and is defined according to 3 categories: high-risk interventional RIPH, low-risk interventional RIPH and non-interventional RIPH. This recent development in the supervision of research on human subjects had several objectives: to redefine the various categories of research, to strengthen data protection and to effectively address the ethical guidelines of international journals. The levels of constraint differ between categories of research according to level of risk, the common objective being to ensure patient protection. Retrospective studies based on information drawn from medical records or other databases, which are widely used in the surgical field, are not covered by the Jardé law. However, they require approval by local ethics committees and compliance with European legislation on personal data protection. Simplified procedures have been set up by the research and innovation departments in our university hospitals. In this update, we shall synthesize the legal prerequisites applying to retrospective studies on data from medical files.


Asunto(s)
Investigación Biomédica , Humanos , Registros Médicos , Estudios Retrospectivos
5.
Geohealth ; 6(3): e2021GH000534, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35280229

RESUMEN

A significant fraction of Brazil's population has been exposed to drought in recent years, a situation that is expected to worsen in frequency and intensity due to climate change. This constitutes a current key environmental health concern, especially in densely urban areas such as several big cities and suburbs. For the first time, a comprehensive assessment of the short-term drought effects on weekly non-external, circulatory, and respiratory mortality was conducted in 13 major Brazilian macro-urban areas across 2000-2019. We applied quasi-Poisson regression models adjusted by temperature to explore the association between drought (defined by the Standardized Precipitation-Evapotranspiration Index) and the different mortality causes by location, sex, and age groups. We next conducted multivariate meta-analytical models separated by cause and population groups to pool individual estimates. Impact measures were expressed as the attributable fractions among the exposed population, from the relative risks (RRs). Overall, a positive association between drought exposure and mortality was evidenced in the total population, with RRs varying from 1.003 [95% CI: 0.999-1.007] to 1.010 [0.996-1.025] for non-external mortality related to moderate and extreme drought conditions, from 1.002 [0.997-1.007] to 1.008 [0.991-1.026] for circulatory mortality, and from 1.004 [0.995-1.013] to 1.013 [0.983-1.044] for respiratory mortality. Females, children, and the elderly population were the most affected groups, for whom a robust positive association was found. The study also revealed high heterogeneity between locations. We suggest that policies and action plans should pay special attention to vulnerable populations to promote efficient measures to reduce vulnerability and risks associated with droughts.

6.
Sci Total Environ ; 751: 142332, 2021 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-33182008

RESUMEN

Portugal (Southwestern Europe) experiences a high incidence of dry hazards such as drought, a phenomenon that entails a notable burden of morbidity and mortality worldwide. For the first time in the Lisbon district, a time-series study was conducted to evaluate the impact of drought measured by the Standardised Precipitation Index (SPI) and Standardised Precipitation-Evapotranspiration Index (SPEI) on the daily natural, circulatory, and respiratory mortality from 1983 to 2016. An assessment by gender and adult age population groups (45-64, 65-74, ≥75 years old) was included. To estimate the relative risks and attributable risks, generalised linear models with a Poisson link were used. Additionally, the influence of heatwaves and atmospheric pollution for the period from 2007 to 2016 (available period for pollution data) was considered. The main findings indicate statistically significant associations between drought conditions and all analysed causes of mortality. Moreover, SPEI shows an improved capability to reflect the different risks. People in the 45-64 year-old group did not indicate any significant influence in any of the cases, whereas the oldest groups had the highest risk. The drought effects on mortality among the population varied across the different study periods, and in general, the men population was affected more than the women population (except for the SPEI and circulatory mortality during the long study period). The short-term influence of droughts on mortality could be explained primarily by the effect of heatwaves and pollution; however, when both gender and age were considered in the Poisson models, the effect of drought also remained statistically significant when all climatic phenomena were included for specific groups of the total population and men. This type of study facilitates a better understanding of the population at risk and allows the development of more effective measures to mitigate the drought effects on the population.


Asunto(s)
Sequías , Adulto , Europa (Continente) , Femenino , Humanos , Modelos Lineales , Masculino , Persona de Mediana Edad , Portugal/epidemiología , Factores de Riesgo
7.
Environ Res ; 183: 109200, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-32036270

RESUMEN

Spain is a country of southern Europe that is prone to drought, and it is likely that this type of hydrological extreme will become substantially more frequent and intense in the 21st century, which could lead to greater health risks if adequate adaptive measures are not taken. For the first time, we calculated the relative risks (RRs) of daily natural (ICD10: A00-R99), circulatory (ICD10: I00-I99), and respiratory (ICD: J00-J99) mortality associated with drought events in each province of Spain from 2000 to 2009. For this purpose, we compared the performance of the Standardized Precipitation Index (SPI) and Standardized Precipitation- Evapotranspiration Index (SPEI) obtained at 1 month of accumulation (denoted as SPI-1/SPEI-1) to estimate the short-term risks of droughts on daily mortality using generalised linear models. Attributable risks were calculated from the RR data. The main findings of this study revealed statistically significant associations between the different causes of daily mortality and drought events for the different provinces of Spain, and clear spatial heterogeneity was observed across the country. Western Spain (northwest to southwest) was the region most affected, in contrast to northern and eastern Spain, and daily respiratory mortality was the group most strongly linked to the incidence of drought conditions. Moreover, for a considerable number of provinces, the effect of SPI-1 and SPEI-1 largely reflected the impact of atmospheric pollution and/or heatwaves; however, for other regions, the effect of drought conditions on daily mortality remained when these different climatic events were controlled in Poisson models. When the performances of the SPEI and SPI were compared to identify and estimate the risks of drought on daily mortality, the results were very similar, although there were slight differences in the specific causes of daily mortality.


Asunto(s)
Sequías , Mortalidad , Europa (Continente) , Modelos Lineales , Mortalidad/tendencias , Factores de Riesgo , España/epidemiología
8.
Epidemiol Infect ; 147: e109, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30869022

RESUMEN

As part of the evaluation of the French plan for the elimination of measles and rubella, we conducted a seroprevalence survey in 2013, aimed at updating seroprevalence data for people 18-32 years old. A secondary objective was to estimate measles incidence in this population during the 2009-2011 outbreak, and thus estimate the exhaustiveness of measles mandatory reporting. We used a cross-sectional survey design, targeting blood donors 18-32 years old, living in France since 2009, who came to give blood in a blood collecting site. We included 4647 people in metropolitan France, 806 people in Réunion Island and 496 in the French Caribbean. A further 3942 individuals were interviewed in the south-east region of metropolitan France to estimate the exhaustiveness of measles mandatory reporting. One of the main findings of this survey is that the proportion of people 18-32 years old susceptible to both measles and rubella infections remained high in France in 2013, 9.2% and 5.4%, respectively, in metropolitan France, even after the promotion campaigns about vaccination catch-up during and following the major measles epidemic in 2009-2011. Applying our results to French census data would suggest that around 1 million people aged 18-32 years old are currently susceptible to measles in France, despite this age group being one of the vaccination targets of the national measles elimination plan. Another important finding is that only an estimated 45% of the true number of cases in this age group was actually notified, despite notification being mandatory.


Asunto(s)
Donantes de Sangre/estadística & datos numéricos , Brotes de Enfermedades , Sarampión/epidemiología , Rubéola (Sarampión Alemán)/epidemiología , Adulto , Susceptibilidad a Enfermedades/epidemiología , Francia/epidemiología , Humanos , Incidencia , Prevalencia , Estudios Seroepidemiológicos , Adulto Joven
9.
Sci Total Environ ; 662: 121-133, 2019 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-30690347

RESUMEN

Climate change scenarios indicate an increase in the intensity and frequency of droughts in several regions of the world in the 21st century, especially in Southern Europe, highlighting the threat to global health. For the first time, a time-series diagnostic study has been conducted regarding the impact of droughts in Galicia, a region in north-western Spain, on daily natural-cause mortality, daily circulatory-cause mortality, and daily respiratory-cause mortality, from 1983 to 2013. We analysed the drought periods over the area of interest using the daily Standardized Evapotranspiration-Precipitation Index (SPEI) and the daily Standardized Precipitation Index (SPI), obtained at various timescales (1, 3, 6, 9 months), to identify and classify the intensity of drought and non-drought periods. Generalized linear models with the Poisson regression link were used to calculate the Relative Risks (RRs) of different causes of mortality, and the percentage of Attributable Risk Mortality (%AR) was calculated based on RRs data. According to our findings, there were statistically significant (p < 0.05) associations between drought periods, measured by both the daily SPEI and SPI, and daily mortality in all provinces of Galicia (except Pontevedra) for different timescales. Furthermore, drought periods had a greater influence on daily mortality in the interior provinces of Galicia than in the coastal regions, with Lugo being the most affected. In short term, the effect of droughts (along with heatwaves) on daily mortality was observed in interior regions and was mainly explained by atmospheric pollution effect throughout 2000 to 2009 period in Ourense, being respiratory causes of mortality the group most strongly associated. The fact that droughts are likely to become increasingly frequent and intense in the context of climate change and the lack of studies that have considered the impact of droughts on specific causes of mortality make this type of analysis necessary.


Asunto(s)
Enfermedades Cardiovasculares/mortalidad , Cambio Climático , Sequías , Mortalidad , Enfermedades Respiratorias/mortalidad , Enfermedades Cardiovasculares/etiología , Humanos , Modelos Lineales , Mortalidad/tendencias , Distribución de Poisson , Enfermedades Respiratorias/etiología , Estaciones del Año , España/epidemiología , Factores de Tiempo
10.
Eur J Clin Microbiol Infect Dis ; 35(11): 1851-1855, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27503076

RESUMEN

The increase in the number of clinical isolates of multiresistant Enterobacteriaceae and Pseudomonas aeruginosa raises problems in decision-making on empirical treatments for severe Gram-negative bacilli-associated infections. The aim of our study is to determine the resistance of meropenem in our setting and the co-resistance of a combination of this compound with two antibiotics from different families: amikacin and ciprofloxacin. Between 2009 and 2013, a total of 81,310 clinical isolates belonging to the main species of Enterobacteriaceae and 39,191 clinical isolates of P. aeruginosa isolated in 28 hospitals in the Valencian Community on the South East Mediterranean Coast of Spain were analyzed using data provided by RedMiva (microbiological surveillance network of the Valencian Community). Meropenem resistance in Enterobacteriaceae increased from 0.16 % in 2009 to 1.25 % in 2013. Very few Enterobacteriaceae strains resistant to meropenem were sensitive to ciprofloxacin; in contrast, the combination of meropenem and amikacin led to a marked decrease in the risk of the microorganisms being resistant to both drugs (RR = 34 in 2013). In the case of P. aeruginosa, meropenem resistance also increased (from 14.32 % in 2009 to 24.52 % in 2013). Most meropenem-resistant P. aeruginosa isolates were also resistant to fluoroquinolones. However, the addition of amikacin led to a more than three-fold decrease in the risk of resistance. In our setting, empirical treatment with meropenem is adequate in enterobacterial infections, but poses difficulties when infection due to P. aeruginosa is suspected, in which case a combination of meropenem and amikacin has been shown to have a higher microbiological success rate.


Asunto(s)
Amicacina/farmacología , Antibacterianos/farmacología , Ciprofloxacina/farmacología , Farmacorresistencia Bacteriana , Enterobacteriaceae/efectos de los fármacos , Pseudomonas aeruginosa/efectos de los fármacos , Tienamicinas/farmacología , Amicacina/uso terapéutico , Antibacterianos/uso terapéutico , Ciprofloxacina/uso terapéutico , Quimioterapia Combinada/métodos , Enterobacteriaceae/aislamiento & purificación , Infecciones por Enterobacteriaceae/tratamiento farmacológico , Infecciones por Enterobacteriaceae/microbiología , Humanos , Meropenem , Infecciones por Pseudomonas/tratamiento farmacológico , Infecciones por Pseudomonas/microbiología , Pseudomonas aeruginosa/aislamiento & purificación , Estudios Retrospectivos , España , Tienamicinas/uso terapéutico
11.
Theriogenology ; 83(7): 1162-73, 2015 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-25623231

RESUMEN

The mammalian oocyte is surrounded by a matrix called the zona pellucida (ZP). This envelope participates in processes such as acrosome reaction induction, sperm binding and may be involved in speciation. In cat (Felis catus), this matrix is composed of at least three glycoproteins called ZP2, ZP3, and ZP4. However, recent studies have pointed to the presence of a fourth protein in several mammals (rat, human, hamster or rabbit), meaning that a reevaluation of cat ZP is needed. For this reason, the objective of this research was to analyze the protein composition of cat ZP by means of proteomic analysis. Using ZP from ovaries and oocytes, several peptides corresponding to four proteins were detected, yielding a coverage of 33.17%, 71.50%, 50.23%, and 49.64% for ZP1, ZP2, ZP3, and ZP4, respectively. Moreover, the expression of four genes was confirmed by molecular analysis. Using total RNA isolated from cat ovaries, the complementary deoxyribonucleic acids encoding cat ZP were partially amplified by reverse-transcribed polymerase chain reaction. Furthermore, ZP1 was totally amplified for the first time in this species. As far as we are aware, this is the first study that confirms the presence of four proteins in cat ZP.


Asunto(s)
Gatos/genética , Proteínas del Huevo/análisis , Proteínas del Huevo/genética , Expresión Génica , Glicoproteínas de Membrana/análisis , Glicoproteínas de Membrana/genética , Receptores de Superficie Celular/análisis , Receptores de Superficie Celular/genética , Zona Pelúcida/metabolismo , Secuencia de Aminoácidos , Animales , Proteínas del Huevo/química , Femenino , Glicoproteínas de Membrana/química , Datos de Secuencia Molecular , Sistemas de Lectura Abierta/genética , Proteómica , ARN Mensajero/análisis , Receptores de Superficie Celular/química , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/veterinaria , Zona Pelúcida/química , Glicoproteínas de la Zona Pelúcida
12.
Gene ; 521(1): 204-6, 2013 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-23537992

RESUMEN

Complement component C6 deficiency is a genetic disease presenting as increased susceptibility to invasive Neisseria meningitidis infections. This disorder has rarely been diagnosed in the Spanish population. In this work we report the immunochemical and molecular characterization of complement C6 deficiency in a Spanish patient showing no detectable functional activity of either the classical or alternative complement pathways and reporting a history of several episodes of meningococcal meningitis. The levels of individual complement components C3, C4, C5, C7, C8 and C9 were within the normal range. However, C6 level was low in the patient's serum as measured by radial immunodiffusion. Exon-specific polymerase chain reaction and sequencing of the C6 gene revealed a previously described homozygous single base deletion in exon 6 (c.821delA), leading to a shift in the reading frame that caused the generation of a downstream stop codon, which, in turn, provoked the truncation of the C6 protein (p.Gln274fs). To our knowledge, this is the first report on the c.821delA mutation in the Spanish population, which has previously only been identified in individuals of African ancestry. Characterization of this mutation was thought interesting in order to elucidate its source and help understand the molecular basis of this uncommon deficiency in our population. Moreover, this report highlights the importance of complement screening in cases of repeated meningococcal infections in order to establish its involvement and to consider adequate clinical recommendations such as prophylactic antibiotics or meningococcal vaccines and, subsequently, for genetic counselling.


Asunto(s)
Complemento C6/genética , Síndromes de Inmunodeficiencia/genética , Adulto , Complemento C6/deficiencia , Exones , Femenino , Enfermedades por Deficiencia de Complemento Hereditario , Homocigoto , Humanos , Masculino , Linaje , España
13.
Hum Immunol ; 74(3): 318-24, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23247208

RESUMEN

Cardiac allograft vasculopathy (CAV) is the single most important long-term limitation to heart transplantation. This study aimed to assess the value of monitoring soluble human leukocyte antigen-G (sHLA-G) during the first year post-transplantation to predict the severity of CAV, in 21 out of 77 heart recipients assessed by intravascular ultrasound (IVUS). Serum sHLA-G concentration increased after transplant in recipients free of severe CAV, but decreased in recipients suffering from severe CAV, significant differences between these two groups were found 6 to 12 months post-transplantation. The optimal value of the change in post-transplant sHLA-G for identifying severe CAV was ≥0.062%, which maximized sensitivity (80%) and specificity (100%). Importantly, increases in post-transplant sHLA-G were inversely associated with severe CAV, but directly associated with human cytomegalovirus reactivation. In addition, recipients presenting non-severe CAV or an increased sHLA-G post-transplantation, showed higher numbers of CD8(+)CD28(-) T cells and a down-modulation of CD28 on CD4(+) lymphocytes, which typically identifies CD8(+) regulatory T cells and anergic/tolerogenic T helper cells, respectively. In conclusion, quantification of sHLA-G might offer a complementary non-invasive method for identifying recipients at risk of more severe CAV and who might benefit from earlier preventive therapies, although these results need to be confirmed in larger series.


Asunto(s)
Antígenos HLA-G/inmunología , Trasplante de Corazón/inmunología , Túnica Íntima/inmunología , Adulto , Anciano , Antígenos CD28/inmunología , Antígenos CD28/metabolismo , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD4-Positivos/metabolismo , Linfocitos T CD8-positivos/inmunología , Linfocitos T CD8-positivos/metabolismo , Citomegalovirus/inmunología , Infecciones por Citomegalovirus/inmunología , Infecciones por Citomegalovirus/virología , Ensayo de Inmunoadsorción Enzimática , Femenino , Citometría de Flujo , Antígenos HLA-G/sangre , Antígenos HLA-G/metabolismo , Trasplante de Corazón/efectos adversos , Trasplante de Corazón/métodos , Humanos , Hiperplasia/sangre , Hiperplasia/etiología , Hiperplasia/inmunología , Masculino , Persona de Mediana Edad , Periodo Posoperatorio , Índice de Severidad de la Enfermedad , Solubilidad , Factores de Tiempo , Trasplante Homólogo , Túnica Íntima/diagnóstico por imagen , Túnica Íntima/patología , Ultrasonografía Intervencional , Activación Viral/inmunología
15.
Hum Immunol ; 72(3): 229-37, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21215286

RESUMEN

Natural killer (NK) and CD8(+) T cells may be active elements in the allograft response, but little is known about their role in liver transplantation. Some of these cells express killer immunoglobulin-like receptors (KIRs), which after binding specific ligands may transmit inhibitory/activating signals. In this study, circulating NK and CD8(+) T cells expressing CD158a/h (KIR2DL1/S1) or CD158b/j (KIR2DL2/3/S(2)) receptors were analyzed in 142 liver recipients by flow cytometry. They were underrepresented in patients before transplantation, but following transplantation, whereas the KIR2D(+) NK subsets experienced a late recuperation (day 365) mainly in C2-homozygous patients developing early acute rejection, recovery of the 2 CD8(+)KIR2D(+) T cells started earlier, showing significant differences on day 365 between patients without acute rejection and those suffering from it (p = 0.004 and p < 0.0001, respectively). These differences were also evident when the human leukocute antigen-C genotypes of the recipient were considered. In conclusion, whereas the late recovery of KIR2D(+) NK cells in C2/C2 patients appears to be linked to acute rejection, the increase in early CD8(+)KIR2D(+) T cells in overall liver recipients correlates with a most successful early graft outcome. Therefore, monitoring of KIR2D(+) cells appears to be a useful tool for liver transplant follow-up.


Asunto(s)
Linfocitos T CD8-positivos/inmunología , Trasplante de Hígado/inmunología , Células T Asesinas Naturales/inmunología , Receptores KIR/genética , Receptores KIR/inmunología , Femenino , Citometría de Flujo , Rechazo de Injerto/genética , Rechazo de Injerto/inmunología , Antígenos HLA-C/genética , Antígenos HLA-C/inmunología , Humanos , Masculino , Persona de Mediana Edad , Células T Asesinas Naturales/metabolismo , Receptores KIR2DL1/genética , Receptores KIR2DL1/inmunología , Receptores KIR2DL1/metabolismo , Receptores KIR2DL3/genética , Receptores KIR2DL3/inmunología , Receptores KIR2DL3/metabolismo
16.
Theriogenology ; 75(3): 463-72, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21074836

RESUMEN

The zona pellucida (ZP) is an extracellular coat that surrounds the mammalian oocyte and the early embryo until implantation. This coat mediates several critical aspects of fertilization, including species-selective sperm recognition, the blocking of polyspermy and protection of the oocyte and the preimplantation embryo. Depending on the species, the ZP is composed of three to four different glycoproteins encoded by three or four genes. These genes have been cloned and sequenced for different species. However, controversy exists about the cell type specificity of the ZP glycoproteins, for which several models have been proposed. Different groups have reported that ZP is produced only by the oocytes, by the granulosa cells or by both cell types, depending on the species under study. We recently described the expression of four ZP proteins in the hamster ovary. By means of the complete set of the hamster ZP cDNAs, we undertook the study of the origin and expression pattern of the four ZP genes. In the present work, the expression of ZP1, ZP2, ZP3 and ZP4 is carefully analyzed by in situ hybridization (ISH) in hamster ovaries. Our data suggest that the four hamster ZP genes are expressed in a coordinate and oocyte-specific manner during folliculogenesis. Furthermore, this expression is maximal during the first stages of the oocyte development and declines in oocytes from later development stages, particularly within large antral follicles.


Asunto(s)
Proteínas del Huevo/biosíntesis , Proteínas del Huevo/genética , Glicoproteínas de Membrana/biosíntesis , Glicoproteínas de Membrana/genética , Mesocricetus/metabolismo , Oocitos/metabolismo , Receptores de Superficie Celular/biosíntesis , Receptores de Superficie Celular/genética , Zona Pelúcida/química , Animales , Cricetinae , Femenino , Expresión Génica , Hibridación in Situ , Mesocricetus/genética , Oocitos/química , Oocitos/crecimiento & desarrollo , Folículo Ovárico/fisiología , ARN Mensajero/análisis , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Zona Pelúcida/fisiología , Glicoproteínas de la Zona Pelúcida
18.
Ann N Y Acad Sci ; 1146: 256-90, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19076419

RESUMEN

Cut-off low pressure systems (COLs) are defined as closed lows in the upper troposphere that have become completely detached from the main westerly current. These slow-moving systems often affect the weather conditions at the earth's surface and also work as a mechanism of mass transfer between the stratosphere and the troposphere, playing a significant role in the net flow of tropospheric ozone. In the first part of this work we provide a comprehensive summary of results obtained in previous studies of COLs. Following this, we present three long-term climatologies of COLs. The first two climatologies are based on the conceptual model of a COL, using European Centre for Medium-range Weather Forecasts (ECMWF) analyses (1958-2002) and National Centers for Environmental Prediction-National Center for Atmospheric Research (1948-2006) reanalysis data sets. The third climatology uses a different method of detection, which is based on using potential vorticity as the physical parameter of diagnosis. This approach was applied only to the ECMWF reanalysis data. The final part of the paper is devoted to comparing results obtained by these different climatologies in terms of areas of preferential occurrence, life span, and seasonal cycle. Despite some key differences, the three climatologies agree in terms of the main areas of COL occurrence, namely (1) southwestern Europe, (2) the eastern north Pacific coast, and (3) the north China-Siberian region. However, it is also shown that the detection of these areas of main COL occurrence, as obtained using the potential vorticity approach, depends on the level of isentropic analysis used.


Asunto(s)
Presión Atmosférica , Clima , Tiempo (Meteorología) , China , Región Mediterránea , Océano Pacífico , Siberia
20.
Dev Dyn ; 236(8): 2285-97, 2007 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-17654705

RESUMEN

Fibroblast growth factors (Fgfs) constitute a family of signaling molecules that play essential roles in development. We have studied the expression pattern of mouse Fgf15 in the developing brain. Fgf19 is another member of the FGF family that has been suggested as the chick and human ortholog of mouse and rat Fgf15. Here, we compare the expression pattern during neural development of chick Fgf19 with mouse Fgf15. Unlike Fgf15, Fgf19 presents an expression in the isthmic alar plate, diencephalic and mesencephalic parabasal plates, hindbrain basal plate, as well as in the zona limitans intrathalamica (zli). Moreover, we explored the regulation between Fgf19 and the signaling molecules of the isthmic and zli organizers: Fgf8 and Shh, respectively. Considering the possibility that Fgf19 plays a similar role in humans and chicks, this finding could explain the significant diencephalic phenotypic differences between humans and mice in models and diseases where the Shh pathway is affected.


Asunto(s)
Encéfalo/crecimiento & desarrollo , Factores de Crecimiento de Fibroblastos/genética , Factores de Crecimiento de Fibroblastos/fisiología , Proteínas Hedgehog/fisiología , Animales , Encéfalo/embriología , Sistema Nervioso Central/embriología , Sistema Nervioso Central/crecimiento & desarrollo , Embrión de Pollo , Diencéfalo/embriología , Diencéfalo/crecimiento & desarrollo , Desarrollo Embrionario , Factor 8 de Crecimiento de Fibroblastos/fisiología , Humanos , Ratones
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