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1.
Chinese Journal of Neonatology ; (6): 550-554, 2023.
Article in Chinese | WPRIM | ID: wpr-990784

ABSTRACT

Objective:To study the clinical significance of alveolar-arterial oxygen gradients (P A-aO 2) for late preterm and full-term infants with acute respiratory distress syndrome (ARDS). Methods:From January 2020 to June 2022, infants (gestational age ≥34 weeks) diagnosed with ARDS were admitted to the Neonatology Department of our hospital. The infants were assigned into the invasive group and the non-invasive group according to the ventilation mode. The infants with the same gestational age and diagnosed with neonatal wet lung were assigned into the control group. P A-aO 2 levels within 1 h after birth were compared among the three groups. The correlation of P A-aO 2 with ARDS, ventilation mode and duration were studied. Receiver operating characteristic (ROC) curve was used to determine the predictive value of P A-aO 2 within 1 h after birth for ARDS and the need of invasive ventilation. Results:A total of 36 cases were enrolled in the invasive group, 19 cases in the non-invasive group and 50 cases in the control group. Within 1 h after birth, P A-aO 2 in the invasive group was significantly higher than the non-invasive group and the control group ( P<0.05), and the non-invasive group higher than the control group ( P<0.05). Correlation analysis showed that P A-aO 2 within 1 h after birth in the invasive group was positively correlated with the duration of invasive ventilation and total mechanical ventilation ( r=0.601, P<0.001; r=0.504, P=0.002); P A-aO 2 before successful withdrawal of invasive ventilation was not correlated with subsequent non-invasive ventilation duration; and no correlation existed between P A-aO 2 within 1 h after birth and the duration of non-invasive ventilation in the non-invasive group. The area under the ROC curve for P A-aO 2 within 1 h after birth to predict ARDS was 0.875, with a sensitivity of 87.3% and a specificity of 72.0% at a cutoff value of 50.0 mmHg. The area under the ROC curve for predicting the need for invasive ventilation in infants with ARDS was 0.851, with a sensitivity of 80.0% at a cutoff value of 73.3 mmHg and a specificity of 75.0%. Conclusions:Late preterm and full-term infants have a higher risk of ARDS at P A-aO 2>50.0 mmHg within 1 h after birth. Infants with ARDS are more likely to require invasive ventilation if P A-aO 2>73.3 mmHg. The higher the level of P A-aO 2, the longer the duration of invasive ventilation and total duration of mechanical ventilation.

2.
Chinese Journal of Ultrasonography ; (12): 497-503, 2022.
Article in Chinese | WPRIM | ID: wpr-956623

ABSTRACT

Objective:To investigate the changes of intraventricular pressure differences (IVPDs) and intraventricular pressure gradients (IVPGs) in different diastolic phases of hypertensive patients with different left ventricular configurations by relative pressure imaging (RPI) based on vector flow mapping (VFM), and to explore its diagnostic value for diastolic function in hypertensive patients with different left ventricular configurations.Methods:Totally 180 patients with hypertension were selected from April 2020 to March 2021 in the Outpatient Clinic of the Second Affiliated Hospital of Harbin Medical University. According to the relative wall thickness (RWT) and left ventricular mass index (LVMI), the patients were divided into normal geometry group (NG group, n=62), concentric remodeling group (CR group, n=62) and concentric hypertrophy group (CH group, n=56). Sixty-one healthy volunteers were selected as the control group. Clinical data and echocardiographic parameters were collected and the differences of each parameter among 4 groups were compared. IVPDs and IVPGs in four diastolic phases were obtained by RPI, including isovolumic relaxation (IR), rapid filling (RF), slow filling (SF) and atrial contraction (AC). The differences of IVPDs and IVPGs in each phase of diastole among 4 groups and their correlations with echocardiographic parameters were analyzed, and the diagnostic efficacy of RPI parameters in NG group patients with reduced diastolic function was analyzed by the ROC curve. Results:The absolute values of IVPDs and IVPGs were greater in all subgroups of hypertension than those of the control group at each diastole phase( P<0.001). Pairwise comparisons showed statistically significant differences of IVPDs-IR and IVPGs-IR among 4 groups( P<0.001). They were correlated with E/e′( rs=-0.615, -0.605; all P<0.001). IVPDs-IR and IVPGs-IR had good diagnostic efficacy for the decrease of diastolic function of patients in NG group, the cutoff values were <-0.705 mmHg (AUC=0.935, P<0.001) and <-0.130 mmHg/cm (AUC=0.926, P<0.001). Conclusions:RPI can precisely assess different degrees of diastolic function changes in hypertensive patients with different configurations. IVPDs-IR and IVPGs-IR can be used as potential new indicators for non-invasive early diagnosis of hypertensive patients with reduced diastolic function, which is of great significance for timely clinical intervention and treatment of reversing ventricular remodeling.

3.
Biota Neotrop. (Online, Ed. ingl.) ; 21(4): e20211210, 2021. tab, graf
Article in English | LILACS-Express | LILACS | ID: biblio-1339280

ABSTRACT

Abstract: The Mid-Domain Effect (MDE) and the Rapoport (RE) effect are two biogeographical theories that make predictions about biogeogaphic patterns. MDE predicts higher richness in the central portions of a gradient if it is within a bounded domain. RE predicts a positive relation between altitude and species range size along an altitudinal gradient. Our aim was to document the distribution of spider species richness along an altitudinal gradient in the Brazilian Amazon, and to test the influence of MDE and RE on the diversity patterns. Our study was conducted at the Pico da Neblina (Amazonas state, Brazil), and we sampled spiders at six different altitudes using two methods: nocturnal hand sampling and a beating tray. We obtained 3,140 adult spiders from 39 families, sorted to 529 species/morphospecies. Richness declined continuously with an altitude increase, but the fit with the MDE richness estimates was very weak and was not significant. Range size was not related to altitude, i. e., no RE. Finally, the abundance distribution within each species range varied more specifically, which prevented the occurrence of a RE at the community level. The influence of MDE was extremely low, a consequence of our community characteristics, formed mostly by small range size species. Short and medium range species were located at all altitudes, preventing a significant relation between range size and altitude. The distribution of abundance within a species range varied specifically and do not support a RE hypothesis.


Resumo: O Efeito do Domínio Central (MDE) e o Efeito Rapoport (ER) são duas teorias biogeografias que fazem previsões sobre a distribuição da diversidade ao longo de gradientes. O MDE prevê maior riqueza nas porções centrais de um gradiente, se este estiver dentro de um domínio fechado. O ER prevê uma relação positiva entre altitude e tamanho da distribuição ao longo do gradiente altitudinal. Nosso objetivo foi o de registrar a distribuição de uma comunidade de aranhas ao longo de um gradiente altitudinal na Amazônia Brasileira, e testar se há uma influência do EDC e do ER sobre os padrões de diversidade da comunidade. Nosso estudo foi feito no Parque Nacional do Pico da Neblina (AM, Brasil), e nós amostramos aranhas em seis altitudes diferentes. Nós coletamos 3.140 exemplares adultos de 39 famílias, que foram divididos em 529 espécies/morfoespécies. A riqueza declinou com o aumento de altitude, mas o padrão não mostrou ajuste com as previsões feitas pelo EDC. O tamanho da distribuição altitudinal também não esteve relacionado ao previsto pelo ER. Por fim, a distribuição de abundância ao longo da distribuição altitudinal das espécies variou de maneira específica, o que impediu a ocorrência de um ER nos padrões da comunidade. A influência do EDC sobre os padrões observados foi baixíssima, uma consequência de características de nossa comunidade, já que esta é formada por espécies com pequena distribuição altitudinal. Espécies de distribuição altitudinal médias e grandes ocorreram em todas as partes do gradiente o que impediu a ocorrência de um ER. Por fim, o ER também não foi observado na distribuição de abundância das espécies ao longo do gradiente, já que essa variou de maneira específica.

4.
Rev. biol. trop ; 68(1)mar. 2020.
Article in Spanish | LILACS-Express | LILACS | ID: biblio-1507654

ABSTRACT

Introducción: Las características de los humedales costeros son resultado de las interacciones hidrogeomorfológicas entre el continente y el océano, que causan un gradiente ambiental, que resulta en diferentes tipos de vegetación como manglares, popales, tulares, selvas y palmares inundables. Objetivo: Caracterizar las variables del hidroperiodo y fisicoquímicas del agua y suelo para determinar la relación que existe en el patrón de distribución de la vegetación en el Sistema de Humedales El Castaño (SHC). Metodología: Se establecieron 11 unidades de muestreo (UM) permanentes por estrato definidos: cinco en el manglar, dos en selvas inundables, dos en tular y dos en pastizal inundable. De mayo 2016 a octubre 2017 se caracterizó la vegetación y se muestreó mensualmente los niveles de inundación y parámetros fisicoquímicos del agua (superficial, intersticial y subterránea): salinidad, conductividad y pH; y el suelo: densidad aparente, porcentaje de humedad y potencial redox. Resultados: El manglar es el más cercano al mar, tiene la menor diversidad (H:1.66) y especies registradas (14), está dominado por Laguncularia racemosa y Rhizophora mangle y tiene los valores más altos de salinidad intersticial y subterránea, mayores a 10.8 ups, se mantiene inundado de 4 a 12 meses, su potencial redox es de 14.57 mV. Seguido está el manglar, tierra adentro, se ubican los remanentes de la selva inundable, (H:2.18 y 18 especies), dominada por Pachiraaquatica, la salinidad intersticial y subterránea de 4.95 ups, permanece inundada de 0 a 6 meses y el potencial redox es de 119.07 mV. El tular, después de la selva, (H:1.92 y 16 especies), dominado por Typha domingensis, salinidad intersticial y subterránea de 6.1 ups, el tiempo de inundación es de 5 a 8 meses y potencial redox es de 125.9 mV. El pastizal inundable, con menor influencia marina, es un humedal herbáceo modificado para uso ganadero, presentó los valores más altos de diversidad (H:3.44 y 50 especies), Paspalum conjugatum es la especie dominante, la salinidad intersticial y subterránea es menor a 0.5 ups, se mantiene inundado de 5 a 9 meses y el potencial redox es de 151.23 mV. Conclusiones: En cada tipo de vegetación, la estructura, composición y diversidad es diferente, con un alto recambio de especies que indica un gradiente definido por la salinidad. La vegetación en el SHC sigue los patrones de organización típica de los humedales costeros tropicales, manglares, selvas inundables y humedales herbáceos, en este caso los tulares y pastizales inundables. El factor que define la distribución de la vegetación, es salinidad y el gradiente que se observa está en función de la dinámica hidrológica que depende de entradas de agua marina y de la bajada de agua dulce del interior del continente.


Introduction: The characteristics of coastal wetlands are the result of hydrogeomorphological interactions between the continent and the ocean, which cause an environmental gradient, hat results in different vegetation types such as mangroves, freshwater marshes, swamp forests and palm swamps. Objective: To characterize the hydroperiod and physicochemical variables of water and soil and their effect on the distribution of vegetation in the Sistema de Humedales El Castaño. Methods: A total of 11 permanent sampling units (UM) were established by defined strata: five in the mangrove, two in swamp forest, two in freshwater marshes and two in the flooded pasture. From May 2016 to October 2017 the vegetation was characterized and the water levels and physicochemical parameters (superficial, interstitial and groundwater) were sampled monthly for: salinity, and pH; and the soil for: bulk density, humidity percentage, and redox potential. Results: Mangroves are the closest to the sea, have the lowest diversity (H: 1.66) and species richness (14), they are dominated by Laguncularia racemosa and Rhizophora mangle, have the highest values of interstitial and groundwater salinity, (> 10.8 ups), remain flooded for 4 to 12 months per year, and have a redox potential of 14.57 mV. Immediately, inland, there are remnants of the swamp forests (H: 2.18 and 18 species), dominated by Pachira aquatica, with 5 ups interstitial and groundwater salinity, flooded from 0 to 6 months per year, with a redox potential of 119.07 mV. These forests are followed inland by freshwater marshes (H: 1.92 and 16 species), dominated by Typha domingensis with 6.1 ups interstitial and groundwater salinity, flooded for 5 to 8 months per year and a redox potential of 125.9 mV. Finally, furthest inland is the flooded pasture, a modified herbaceous wetland for cattle grazing (H: 3.44 and 50 species) dominated by Paspalum conjugatum, where interstitial and groundwater salinity is less than 0.5 ups, it stays flooded for 5 to 9 months and the redox potential is 151.23 mV. Conclusions: In each type of vegetation, the structure, composition, and diversity are different, with a high turnover of species that indicates a gradient defined by salinity. The vegetation in the SHC follows the patterns of typical organization of the tropical coastal wetlands, mangroves, swamp forests and herbaceous wetlands, in this case the freshwater marshes and flooded pastures. The factor that define the distribution of the vegetation is the salinity and the gradient that is observed are a function of the hydrological dynamics that depends on the mixing of marine and freshwater.

5.
Pesqui. vet. bras ; 40(3): 197-201, Mar. 2020. tab
Article in English | VETINDEX, LILACS | ID: biblio-1135609

ABSTRACT

The temperature gradients are dynamic and noninvasive monitoring techniques that provide information on peripheral blood flow and have been related to the prognosis of patients with circulatory shock. This study evaluated 47 elderly domestic cats' temperature gradients, and we measured central (rectal) and peripheral (palmar, plantar and medial region of the radio) temperatures. Values found in this study are compatible with studies in young felines and differ from dogs and humans. The mean gradients found were 7.5°C for the central-peripheral; 5.6°C for the peripheral-environmental; 2.7°C for the skin-diff; and 0°C for the member-diff and the variables age and gender do not seem to influence these measurements. To the authors' knowledge, there is no description of temperature gradients in elderly domestic cats, so this study pretends to clarify the vasoconstriction response in this group of animals.(AU)


Os gradientes de temperatura são técnicas de monitoração dinâmicas e não-invasivas que fornecem informações sobre o fluxo sanguíneo periférico, e têm sido relacionados ao prognóstico de paciente com choque circulatório. O presente estudo avaliou os gradientes de temperatura em 47 felinos domésticos idosos aferindo as temperaturas central (retal) e periférica (palmar, plantar e região medial do rádio). Os gradientes encontrados foram 7,5°C para o centro-periférico; 5,6°C para o periférico-ambiental; 2,7°C para o skin-diff; e 0°C para o member-diff. As variáveis idade e sexo não pareceram influenciar as mensurações. Não há, em conhecimento dos autores, descrição prévia dos gradientes de temperatura em felinos domésticos idosos, e por isso esse estudo pretende contribuir com o entendimento sobre a capacidade de resposta de vasoconstrição nesse grupo de animais.(AU)


Subject(s)
Animals , Cats , Shock/diagnosis , Shock/prevention & control , Skin/blood supply , Vasoconstriction , Body Temperature , Thermometers
6.
Rev. biol. trop ; 67oct. 2019.
Article in English | LILACS-Express | LILACS | ID: biblio-1507476

ABSTRACT

Introduction: The Río Lagartos lagoon, located in the Ría Lagartos Biosphere Reserve, Yucatán, Gulf of Mexico, is a coastal hypersaline system ca. 80 km long (east-west). It comprises three basins: western (close to Río Lagartos fishermen village), middle (Las Coloradas) and eastern (close to El Cuyo fishermen village), that communicate through very narrow natural channels. Despite several studies have been performed on the vertebrate fauna, the aquatic invertebrates, and especially polychaetes, remain largely unknown. Objective: The objective of this study is to describe the composition and distribution of the benthic polychaete community, and to analyse potential environmental drivers. Methods: The biological material was collected in 16 stations distributed along the lagoon during the rainy season (September 2017). Two replicates per station were obtained using a Ponar standard dredge or cores (6" diameter). Environmental variables such as grain size, organic carbon content in the sediments, and salinity, among others, were measured. Results: A total of 827 specimens belonging to 26 species and 16 families were identified. Of these, 23 species are new records for the Río Lagartos lagoon. Community composition changed between the different basins associated with strong gradients in salinity, subaquatic vegetation (algae and seagrasses) proportions in the samples and grain size. No polychaetes were recorded at the easternmost basin (El Cuyo basin), where salinity was between 67-80 psu. In the rest of the lagoon, the distribution of polychaetes was heterogeneous, especially near the mouth (western basin), where the highest and lowest density, species richness and diversity were recorded. The highest density was found at station 6, where dense algal mats of the genus Avrainvillea dominated. The families Syllidae and Nereididae were the most abundant and widely distributed families in the lagoon. The species Syllis lagunae and Nereis pelagica dominated the western basin and Prionospio heterobranchia and Sphaerosyllis taylori dominated the middle basin. Conclusions: The salinity records associated with some species were well above the top limits previously reported, establishing the euryhaline character of many species in the region.


Introducción: La laguna Río Lagartos, ubicada en la Reserva de la Biosfera Ría Lagartos, Yucatán, Golfo de México, es un sistema costero hipersalino con una longitud aproximada de 80 km (este-oeste). La laguna está conformada por tres cuencas (Río Lagartos, Las Coloradas y El Cuyo) comunicadas entre sí por canales naturales extremadamente estrechos. Aunque existen varios estudios sobre la fauna vertebrada asociada a la laguna, los invertebrados acuáticos, y especialmente la poliquetofauna, son todavía desconocidos. Objetivo: El objetivo de este estudio es analizar la composición y distribución de los poliquetos bentónicos, y su relación con las condiciones ambientales. Metodología: El material biológico fue recolectado en 16 estaciones a lo largo del sistema lagunar durante la época climática de "lluvias" (septiembre 2017). Se tomaron dos réplicas por estación con una draga Ponar standard o un nucleador de PVC (diámetro= 6"). En cada estación se midieron distintas variables ambientales p. ej., granulometría, carbono orgánico en sedimento, salinidad, entre otras. Resultados: Se identificaron 827 ejemplares pertenecientes a 26 especies y 16 familias. De éstas, 23 especies son nuevos registros para la laguna Río Lagartos. La composición de la comunidad varió entre las distintas cuencas de la laguna en relación con importantes gradientes de salinidad, de la proporción de vegetación (algas y pastos) en la muestra y del tamaño de grano. En la cuenca este, El Cuyo, donde el rango de salinidad fue 67-80 ups, no se encontraron poliquetos. En el resto de la laguna, la distribución de los poliquetos fue heterogénea, especialmente cerca de la boca (cuenca de Río Lagartos), donde se registraron los valores más altos y más bajos de densidad, riqueza específica y diversidad. La densidad más alta se registró en la estación 6, donde la muestra estuvo dominada por densos lechos de algas del género Avrainvillea. Las familias Syllidae y Nereididae fueron las más abundantes y ampliamente distribuidas en la laguna. Las especies Syllis lagunae y Nereis pelagica dominaron en la cuenca de Río Lagartos y Prionospio heterobranchia y Sphaerosyllis taylori, en Las Coloradas. Conclusiones: Los rangos de salinidad reportados para algunas de las especies fueron mucho más altos que registros anteriores, estableciendo el carácter eurihalino de varias especies en la región.

7.
Chinese Journal of Ultrasonography ; (12): 1019-1024, 2019.
Article in Chinese | WPRIM | ID: wpr-824450

ABSTRACT

Objective To evaluate the changes of intraventricular pressure differences(IVPDs)and intraventricular pressure gradients(IVPGs)in different phases of cardiac cycle in patients with heart failure (HF)patients by relative pressure imaging based on vector flow imaging(VFM).Methods Forty-nine HF patients with left ventricular ejection fraction (LVEF) lower than 0.50 hospitalized in Qilu Hospital of Shandong University from November 2018 to January 2019,including thirty-three patients with HF with reduced ejection fraction (HFrEF group) and fifteen patients with midrange ejection fraction (HFmrEF group),and forty-three controls were enrolled in this study.Clinical data and echocardiographic images were collected and the conventional left ventricular diameter,mass,volume,and systolic and diastolic function parameters were measured. IVPDs and IVPGs during isovolemic systole (IC),rapid ej ection (RE), isovolemic diastole (IR),rapid filling (RF) and atrial systole (AC) phases were obtained by the VFM technique.The changes of IVPDs and IVPGs in different phases between the HF and control groups,and their correlations with conventional ultrasound parameters were analyzed.Results IVPDs and IVPGs in heart failure group were significantly reduced compared with the control group especially in isovolumic relaxation phase(all P <0.001).IVPDs and IVPGs showed a decreasing trend in the control group, HFmrEF group and the HFrEF group(P<0.001).IVPDs and IVPGs were correlated with LVID,LVMI,ESV,LVEF,GLS and E/e'(all P <0.01),among which IVPD-IR and IVPG-IR were best correlated. IVPD-IR and IVPG-IR had excellent diagnostic efficacy for HF patients with LVEF<0.5,with cut-off values of<0.73 mmHg(AUC=0.915,P<0.001)and <0.103 mmHg/cm(AUC=0.932,P<0.001), respectively.Conclusions Early diastolic hemodynamics are severely impaired when systolic function declines.IVPG-IR,as a marker of left ventricular diastolic function,significantly correlates with left ventricular systolic function,and can be used as a potential indicator for assessing left ventricular systolic and diastolic function in patients with heart failure and identifying patients with heart failure.

8.
Chinese Journal of Ultrasonography ; (12): 1019-1024, 2019.
Article in Chinese | WPRIM | ID: wpr-800512

ABSTRACT

Objective@#To evaluate the changes of intraventricular pressure differences (IVPDs) and intraventricular pressure gradients (IVPGs) in different phases of cardiac cycle in patients with heart failure(HF) patients by relative pressure imaging based on vector flow imaging(VFM).@*Methods@#Forty-nine HF patients with left ventricular ejection fraction (LVEF) lower than 0.50 hospitalized in Qilu Hospital of Shandong University from November 2018 to January 2019, including thirty-three patients with HF with reduced ejection fraction (HFrEF group) and fifteen patients with midrange ejection fraction (HFmrEF group), and forty-three controls were enrolled in this study. Clinical data and echocardiographic images were collected and the conventional left ventricular diameter, mass, volume, and systolic and diastolic function parameters were measured. IVPDs and IVPGs during isovolemic systole (IC), rapid ejection (RE), isovolemic diastole (IR), rapid filling (RF) and atrial systole (AC) phases were obtained by the VFM technique. The changes of IVPDs and IVPGs in different phases between the HF and control groups, and their correlations with conventional ultrasound parameters were analyzed.@*Results@#IVPDs and IVPGs in heart failure group were significantly reduced compared with the control group especially in isovolumic relaxation phase(all P<0.001). IVPDs and IVPGs showed a decreasing trend in the control group, HFmrEF group and the HFrEF group(P<0.001). IVPDs and IVPGs were correlated with LVID, LVMI, ESV, LVEF, GLS and E/e′ (all P<0.01), among which IVPD-IR and IVPG-IR were best correlated. IVPD-IR and IVPG-IR had excellent diagnostic efficacy for HF patients with LVEF<0.5, with cut-off values of <0.73 mmHg (AUC=0.915, P<0.001) and <0.103 mmHg/cm (AUC=0.932, P<0.001), respectively.@*Conclusions@#Early diastolic hemodynamics are severely impaired when systolic function declines.IVPG-IR, as a marker of left ventricular diastolic function, significantly correlates with left ventricular systolic function, and can be used as a potential indicator for assessing left ventricular systolic and diastolic function in patients with heart failure and identifying patients with heart failure.

9.
Braz. j. biol ; 78(3): 487-500, Aug. 2018. tab, graf
Article in English | LILACS | ID: biblio-951575

ABSTRACT

Abstract Large reservoirs usually present spatial gradients in fish assemblage, distinguishing three strata (littoral, pelagic, and bathypelagic) along the vertical and horizontal axes, and three zones (fluvial, transitional, and lacustrine) along the longitudinal axis. The main objective of this study was to assess if small reservoirs also present the spatial gradients in fish assemblage attributes and structure as already observed in large reservoirs. Fish surveys were conducted quarterly, from 2003 to 2008, in the Mourão Reservoir (Mourão River, Paraná, Brazil), using gillnets with different mesh sizes, arranged in all strata of all three zones. Community attributes (species richness and evenness) were calculated for each sample, and differences were tested using three-way ANOVA (factors: zone, strata, year). Community composition was summarized using Correspondence Analysis (CA) and differences were tested with three-way ANOVA for each axis, controlling the same three factors. Because of the high variability in reservoir water level through time, all analyses were made considering temporal variations. Species richness presented a decreasing trend from fluvial to lacustrine zones, and higher values in littoral strata, possibly because upper reaches and littoral regions provide better conditions for fish to feed and to reproduce. Evenness was considerably low, presenting high variability, and no evident pattern. The expected longitudinal gradient was not found in this study indicating longitudinal similarity, contrary to observed in large reservoirs. Vertical and horizontal gradients were observed in all sampling stations, indicating that abiotic and biotic conditions are influencing fish distributions within the reservoir.


Resumo Grandes reservatórios, em geral, apresentam gradientes espaciais da assembleia de peixes, distinguindo três estratos (litoral, pelágico e batipelágico) ao longo dos eixos vertical e horizontal, e três zonas (fluvial, transição e lacustre) ao longo do eixo longitudinal. O principal objetivo deste estudo foi avaliar se pequenos reservatórios também apresentam tais gradientes espaciais, nos atributos e na estrutura da assembleia de peixes, como já observado em grandes reservatórios. As coletas dos peixes foram realizadas trimestralmente, de 2003 a 2008, no reservatório de Mourão (Rio Mourão, Paraná, Brasil), com redes de espera com diferentes tamanhos de malha, dispostas em todos os estratos de todas as três zonas. Atributos da assembleia (riqueza de espécies e equitabilidade) foram calculados para cada amostra, e as diferenças foram testadas utilizando ANOVA tri-fatorial (fatores: zona, estratos, anos). A estrutura da assembleia foi sumarizada usando uma Análise de Correspondência (CA) e as diferenças foram testadas com ANOVA tri-fatorial para cada eixo, controlando os mesmos três fatores. Devido à alta variabilidade no nível da água do reservatório ao longo do tempo, todas as análises foram feitas considerando as variações temporais. A riqueza de espécies apresentou tendência decrescente, da zona fluvial até a lacustre, com valores maiores no estrato litoral, possivelmente porque locais à montante e regiões litorâneas proporcionam melhores condições de alimentação e reprodução para os peixes. A equitabilidade foi consideravelmente baixa, apresentando alta variabilidade e nenhum padrão evidente. O gradiente longitudinal esperado não foi encontrado neste estudo, indicando similaridade longitudinal, ao contrário do observado em grandes reservatórios. Gradientes verticais e horizontais foram observadas em todas as áreas amostradas, sugerindo que as condições bióticas e abióticas estão influenciando a distribuição dos peixes ao longo do reservatório.


Subject(s)
Animals , Biodiversity , Spatio-Temporal Analysis , Fishes , Fresh Water , Seasons , Brazil , Population Density , Rivers
10.
Rev. biol. trop ; 66(4): 1469-1480, oct.-dic. 2018. tab, graf
Article in English | LILACS | ID: biblio-1003338

ABSTRACT

Abstract Gall-inducing insects manipulate the structural, histochemical and physiological profiles of host-plant tissues to develop galls. We evaluated galls induced by Eugeniamyia dispar on the leaves of Eugenia uniflora in an attempt to answer the following questions: (i) How does this gall-inducing insect change the structural and histochemical profiles of the host-plant organ? (ii) Despite structural changes, can gall tissues maintain photosynthetic activity? Starch, proteins, reducing sugars and reactive oxygen species were detected mainly in the nutritive tissue surrounding the larval chamber. Despite structural changes, the galls induced by E. dispar on E. uniflora retain chlorophyllous tissue, although its amount and photosynthetic activity are less than that of non-galled leaves. This reduced photosynthetic activity, in association with the presence of large intercellular spaces, could improve gas diffusion and, consequently, avoid hypoxia and hypercarbia in gall tissue.(AU)


Resumen Los insectos que inducen las agallas manipulan los perfiles estructurales, histoquímicos y fisiológicos de los tejidos de la planta hospedera para su desarrollo. Nosotros evaluamos las agallas inducidas por Eugeniamyia dispar en las hojas de Eugenia uniflora en un intento de responder las siguientes preguntas: (i) ¿Cómo este insecto inductor de agallas cambia los perfiles estructurales e histoquímicos en el órgano de la planta hospedera? (ii) A pesar de las modificaciones estructurales, ¿pueden los tejidos de la agalla mantener la actividad fotosintética? El almidón, las proteínas, los azúcares reductores y las especies reactivas de oxígeno se detectaron principalmente en la capa de tejido nutritivo que rodea a la cavidad larval. A pesar de las modificaciones estructurales, las agallas inducidas por E. dispar en E. uniflora retienen su tejido clorofílico, aunque su cantidad y actividad fotosintética son menores que en las hojas no agalladas. Esta actividad fotosintética reducida, asociado a la presencia de grandes espacios intercelulares, pueden mejorar la difusión de gases y, en consecuencia, evitar la hipoxia y la hipercapnia en los tejidos de las agallas.(AU)


Subject(s)
Photosynthesis , Diptera , Eugenia , Chlorophyll A , Hypoxia
11.
Chinese Pharmacological Bulletin ; (12): 1030-1036, 2018.
Article in Chinese | WPRIM | ID: wpr-705171

ABSTRACT

Aim To establish a rapid method to efficiently iso-late mononuclear cells from central nervous system ( CNS) tis-sues of mice that can be effectively utilized for identification of various immune cell populations in a single sample by flow cy-tometry. Methods For defining the feasibility and practicality of the method, wild-type C57BL/6 mice and two mouse models of CNS disease including EAE mice and APP/PS1 mice were used in this study. After the collection and homogenization of the brain and spinal cord tissues respectively, the mononuclear cells were isolated by spinning the 70% -30% Percoll gradients. Cell activities were detected by trypan blue staining, and the im-mune population that infiltrated CNS was identified by flow cy-tometry. Results The results of trypan blue staining showed that the survival rate of the isolated cells was above 90% in all groups. Flow cytometry analysis showed that the relative num- bers of lymphocytes infiltrating CNS of EAE and AD mice in-creased significantly compared with wild-type C57BL/6 mice. In addition, the relative numbers of Th1 and Th17 cell subsets me-diating the inflammatory response also increased significantly, while the decreased regulatory T cells frequency was observed in the two mouse models of CNS disease. Conclusions The cells isolated by the 70% ~30% Percoll gradients centrifugation can be effectively utilized for the identification of various immune cell populations in a single sample by flow cytometry. The meth-od described in this article is simple and rapid in operation and with high survival rate and activity of the cells, which can be ap-plied to the study of the mononuclear cells in CNS.

12.
Article in English | LILACS-Express | LILACS, VETINDEX | ID: biblio-1467116

ABSTRACT

Abstract Large reservoirs usually present spatial gradients in fish assemblage, distinguishing three strata (littoral, pelagic, and bathypelagic) along the vertical and horizontal axes, and three zones (fluvial, transitional, and lacustrine) along the longitudinal axis. The main objective of this study was to assess if small reservoirs also present the spatial gradients in fish assemblage attributes and structure as already observed in large reservoirs. Fish surveys were conducted quarterly, from 2003 to 2008, in the Mourão Reservoir (Mourão River, Paraná, Brazil), using gillnets with different mesh sizes, arranged in all strata of all three zones. Community attributes (species richness and evenness) were calculated for each sample, and differences were tested using three-way ANOVA (factors: zone, strata, year). Community composition was summarized using Correspondence Analysis (CA) and differences were tested with three-way ANOVA for each axis, controlling the same three factors. Because of the high variability in reservoir water level through time, all analyses were made considering temporal variations. Species richness presented a decreasing trend from fluvial to lacustrine zones, and higher values in littoral strata, possibly because upper reaches and littoral regions provide better conditions for fish to feed and to reproduce. Evenness was considerably low, presenting high variability, and no evident pattern. The expected longitudinal gradient was not found in this study indicating longitudinal similarity, contrary to observed in large reservoirs. Vertical and horizontal gradients were observed in all sampling stations, indicating that abiotic and biotic conditions are influencing fish distributions within the reservoir.


Resumo Grandes reservatórios, em geral, apresentam gradientes espaciais da assembleia de peixes, distinguindo três estratos (litoral, pelágico e batipelágico) ao longo dos eixos vertical e horizontal, e três zonas (fluvial, transição e lacustre) ao longo do eixo longitudinal. O principal objetivo deste estudo foi avaliar se pequenos reservatórios também apresentam tais gradientes espaciais, nos atributos e na estrutura da assembleia de peixes, como já observado em grandes reservatórios. As coletas dos peixes foram realizadas trimestralmente, de 2003 a 2008, no reservatório de Mourão (Rio Mourão, Paraná, Brasil), com redes de espera com diferentes tamanhos de malha, dispostas em todos os estratos de todas as três zonas. Atributos da assembleia (riqueza de espécies e equitabilidade) foram calculados para cada amostra, e as diferenças foram testadas utilizando ANOVA tri-fatorial (fatores: zona, estratos, anos). A estrutura da assembleia foi sumarizada usando uma Análise de Correspondência (CA) e as diferenças foram testadas com ANOVA tri-fatorial para cada eixo, controlando os mesmos três fatores. Devido à alta variabilidade no nível da água do reservatório ao longo do tempo, todas as análises foram feitas considerando as variações temporais. A riqueza de espécies apresentou tendência decrescente, da zona fluvial até a lacustre, com valores maiores no estrato litoral, possivelmente porque locais à montante e regiões litorâneas proporcionam melhores condições de alimentação e reprodução para os peixes. A equitabilidade foi consideravelmente baixa, apresentando alta variabilidade e nenhum padrão evidente. O gradiente longitudinal esperado não foi encontrado neste estudo, indicando similaridade longitudinal, ao contrário do observado em grandes reservatórios. Gradientes verticais e horizontais foram observadas em todas as áreas amostradas, sugerindo que as condições bióticas e abióticas estão influenciando a distribuição dos peixes ao longo do reservatório.

13.
Rev. biol. trop ; 64(4): 1537-1551, oct.-dic. 2016. tab, ilus
Article in Spanish | LILACS | ID: biblio-958233

ABSTRACT

Resumen:Los estudios sobre gradientes altitudinales han permitido examinar cambios en la riqueza y composición de los ensamblajes de aves, lo que hace posible obtener información sobre las variables ambientales que determinan su distribución y factores que definen la estructura. En este trabajo se describe la variación en la riqueza y composición de los ensamblajes de aves a través de un gradiente altitudinal al sur de Nayarit. Para analizar el comportamiento de la riqueza en el gradiente se obtuvo información mediante puntos de conteo en nueve intervalos altitudinales (separados cada 300 m de altitud) desde el nivel del mar hasta los 2 700 msnm. Se estandarizó el esfuerzo de muestreo y se realizaron curvas de rarefacción, y los cambios en la composición de especies se analizaron mediante análisis de clasificación jerárquica utilizando la técnica TWINSPAN. Para identificar las variables asociadas con los cambios en riqueza se analizó el efecto de la precipitación y de la estructura del hábitat mediante árboles de regresión. Para determinar si los cambios en composición responden a cambios en los tipos de vegetación se realizó un análisis de escalamiento multidimensional no métrico (NMDS). La riqueza de especies varió de forma significativa a través del gradiente: fue alta en las partes bajas del gradiente, alcanzó su valor máximo en la parte media y disminuyó monotónicamente con la elevación. Las especies respondieron a cambios en el gradiente y se agruparon en tres pisos altitudinales. Los análisis sugieren que los cambios en la riqueza y composición de las especies están influenciados por la vegetación, su estructura y precipitación, así como por diversos aspectos relacionados con características del hábitat y la perturbación. Estos aspectos deberán ser tomados en cuenta con el fin de diseñar estrategias adecuadas para la conservación de las aves de Nayarit.


Abstract:Elevation gradient studies have strengthened the evaluation of changes in richness and composition of bird assemblages. They also provide information on environmental variables that determine bird distribution, and the variables that define their population structure. Our aim was to describe their variation through an elevational cline in Southern Nayarit, Mexico. To analyze the behavior of richness across the gradient, we gathered information through point counts in nine elevational intervals (300 m from each other) from sea level to 2 700 m of elevation. With a standardized sampling effort, we produced rarefaction curves and analyzed changes in species composition by hierarchical classification using the TWINSPAN technique. In order to identify variables associated with richness changes, we examined the effect of precipitation and habitat structure via regression trees. An analysis of nonmetric multidimensional scaling (NMDS) was implemented with the purpose to determine if the changes in composition correspond to changes in vegetation types. Species richness varied significantly across the gradient: high in the lower parts of the gradient, reached its peak in the middle, and decreased monotonically with elevation. Species responded to changes in the cline and were grouped in three elevational zones. Analyses suggest that changes in richness and species composition are influenced by vegetation, its structure and precipitation regime, as well as various aspects related to habitat features and disturbance. These aspects should be taken into account in order to design appropriate strategies for the conservation of the birds of Nayarit. Rev. Biol. Trop. 64 (4): 1537-1551. Epub 2016 December 01.


Subject(s)
Animals , Birds/classification , Altitude , Animal Distribution , Species Specificity , Birds/physiology , Forests , Population Dynamics , Climate , Biodiversity , Mexico
14.
Mem. Inst. Oswaldo Cruz ; 111(11): 676-685, Nov. 2016. tab, graf
Article in English | LILACS | ID: biblio-829251

ABSTRACT

Given their medical and veterinary relevance, the members of the Pipiens Assemblage are a worldwide target of ecological research. The distribution of Culex pipiens s.s. and Cx. quinquefasciatus converge in Buenos Aires, Argentina, where hybrids have been detected. Each member of the assemblage exhibits a distinct eco-physiological behaviour that can affect its efficiency in pathogen transmission. Our aim was to identify the environmental drivers for the spatio-temporal distribution of each member, focusing on latitudinal and urbanisation gradients. Immatures of mosquitoes were surveyed in artificial containers found within 11 public cemeteries, raised up to the adult stage and identified by their male genitalia. The distribution of each member was associated with the environment in a Generalized Linear Model. The variable accounting for most of the heterogeneity was latitude; Cx. quinquefasciatus was collected more frequently at northern cemeteries, whereas Cx. pipiens and hybrids were more likely at the southern extreme. The urbanisation gradient was also associated with the occurrence of Cx. quinquefasciatus and hybrids at the high and low end, respectively. Other relevant variables were cemetery total area, the proportion with graves and the presence of plastic flowers in the containers. The spatial distribution of the members of the Pipiens Assemblage within the sympatric region in South America is driven by environmental features. The information presented herein provides essential baseline data for surveillance programs and control activities.


Subject(s)
Animals , Male , Female , Animal Distribution/physiology , Culex/physiology , Disease Vectors/classification , Ecosystem , Urbanization , Argentina , Culex/classification , Culex/growth & development , Population Density , Seasons , Spatio-Temporal Analysis , Species Specificity , Temperature
15.
Chinese Journal of Analytical Chemistry ; (12): 965-969, 2016.
Article in Chinese | WPRIM | ID: wpr-494379

ABSTRACT

A technique of diffusive gradients in thin films (DGT) was developed for the in situ measurement of reactive phosphorus species in natural waters, sediments and potentially soils. Polyacrylamide / basic magnesium carbonate was used as the novel binding phase of DGT. Various factors, such as initial concentration, deployment time, pH and ionic strength, which may affect the adsorption of phosphate to the DGT were investigated. H2 SO4(0. 25 mol/ L, 10 mL) was used for elution of phosphate from the binding gel, and an elution efficiency of 85±5% was obtained. The DGT measurement was independent of ionic strength (0. 001-0. 05 mol/ L) and pH (4. 10-9. 15). The results indicated that the maximum adsorption capacities of DGT were limited to 20. 4 μg per disc ( T = 25℃, pH = 7. 00, [ P] = 2 mg / L). Good agreement was obtained between the measurement results of DGT method and molybdenum blue method in the P concentration from 0. 001 to 20 mg / L. The method detection limit (MDL) was 102. 4 ng / L. Field performances of DGT in synthetic seawater, the coastal seawater of Xiamen, Lake Yihai, Lake Chaohu and Nanfei River indicated that the basic magnesium carbonate-DGT method was more reliable than the commonly used ferrihydrite-DGT method.

16.
Int. j. morphol ; 32(4): 1222-1227, Dec. 2014. ilus
Article in English | LILACS | ID: lil-734662

ABSTRACT

This investigation was undertaken in order to quantify the effects of early polysensorial enrichment on the development of cortical pyramids, located in the parietal cortex of rats simultaneously submitted to protein-energy undernutrition. A short period of stimulation during suckling significantly decreases the cellular density in the cortical plate (phylogenetic-ontogenetic evolutionary index). Results suggest that the cerebral cortex develops according to a sophisticated neuronal network, which exhibits a notable degree of structural specificity, regulated by genetic and environmental clues. The most obvious prediction is that environmental influences are probably transduced as a structural expression in the developing parietal cortical plate.


La presente investigación se realizó con la finalidad de cuantificar los efectos del enriquecimiento polisensorial temprano sobre el desarrollo de células piramidales de la corteza parietal, en ratas que simultáneamente fueron sometidas a desnutrición calórico-proteica. Un breve periodo de estimulación durante el periodo de lactancia disminuyó significativamente la densidad celular en la placa cortical (índice evolutivo filogenético-ontogenético). Los resultados sugieren que la corteza cerebral se desarrolla de acuerdo con una red neuronal altamente sofisticada, la cual exhibe un notable grado de especificidad estructural regulada por claves genéticas y ambientales. La predicción más obvia es que las influencias ambientales son probablemente traducidas como expresión estructural en la placa cortical parietal.


Subject(s)
Animals , Rats , Parietal Lobe/anatomy & histology , Parietal Lobe/growth & development , Protein-Energy Malnutrition , Environment , Rats, Sprague-Dawley
17.
Rev. biol. trop ; 62(3): 987-996, jul.-sep. 2014. graf, tab
Article in Spanish | LILACS | ID: lil-753669

ABSTRACT

Most Andean mountain streams of the Orinoco Basin in Venezuela, had been suffering various disturbances. in spite of this, fish communities have been poorly evaluated in terms of spatial and temporal gradients. Thus, the generation of information about these communities is a priority, since it may support conservation of regional hydrobiological resources. For this, six sites were monthly evaluated in tributaries of upper Turbio River in Sierra de Portuguesa (770-1 305msnm), during the dry season and the beginning of the rainy season (January-April 2012); we characterized stream dimensions, substrate and water physicochemical variables. Electrofishing was used to determine the number and abundance of fish species. The fish communities and their stability were evaluated by exploring the changes in richness and abundance, coefficients of variation, hierarchical classification and non-metrical multidimensional scaling analysis. The sites conservation status was estimated with a habitat integrity index. Our results showed that richness of the 12 species found varied according to the mountain elevation, the tributaries and the conservation status of the sites. Chaetostoma dorsale, Creagrutus taphorni and Chaetostoma milesi comprised 90.8% of the relative abundance, and maintained the first ranks during the study period. The communities had little spatio-temporal variation which was associated with a gradient signed principally by the amount of shadow, rocks and gravel cover, water temperature and conductivity. Stability was moderate but varied with elevation and according to site conservation status. The tributaries in upper Turbio River were found to be under severe impacts and their fishes were found impoverished and at risk.


La mayoría de los ríos en las montañas andinas de Venezuela en la cuenca del Orinoco sufren variadas perturbaciones. A pesar de esto, sus comunidades de peces han sido poco evaluadas en términos de sus gradientes espaciales y temporales. La generación de información sobre estas comunidades es prioritaria, y puede impulsar la conservación de los recursos hidrobiológicos regionales. Con este fin, seis localidades fueron evaluadas mensualmente en tributarios de la cuenca alta del río Turbio en la Sierra de Portuguesa (770-1 305msnm) durante el período de sequía y el inicio del período de lluvias (enero-abril de 2012), se caracterizaron las dimensiones del cauce, el sustrato y las variables físico-químicas del agua. Se utilizó electropesca para determinar el número y abundancia de especies de peces. Las comunidades de peces y su estabilidad se evaluaron explorando los cambios en la riqueza y abundancia y por coeficientes de variación, clasificación jerárquica y análisis de escalamiento multidimensional no métrico. El estado de conservación de las localidades se estimó con un índice de integridad del hábitat. La riqueza de 12 especies varió según la elevación, los tributarios y el estado de conservación de las localidades. Chaetostoma dorsale, Creagrutus taphorni y Chaetostoma milesi comprendieron el 90.8% de la abundancia relativa y mantuvieron los primeros rangos durante el período. Las comunidades tuvieron poca variación espacio-temporal y esta se expresó en un gradiente asociado principalmente por las coberturas de sombra, rocas y grava, la temperatura del agua y la conductividad. La estabilidad fue moderada, variando con la elevación y el estado de conservación de las localidades. Los tributarios en la cuenca alta del río Turbio se encuentran bajo impactos severos y sus ictiofaunas son empobrecidas y en situación de riesgo.


Subject(s)
Animals , Biodiversity , Fishes/classification , Rivers , Population Density , Population Dynamics , Seasons , Venezuela
18.
Acta sci., Biol. sci ; 34(1): 69-75, Jan.-Mar. 2012.
Article in Portuguese | LILACS-Express | LILACS, VETINDEX | ID: biblio-1460700

ABSTRACT

Several ecological hypotheses try to explain geographical patterns in biodiversity. The Metabolic Theory of Ecology (MTE) predicts that temperature is the main determinant of richness patterns for ectothermic organisms and that the relationship between richness (lnS) and temperature (1/kT) is a linear relationship with angular coefficient (b) near -0.65. This study tested the MTE for continental zooplankton diversity in 63 lakes in Brazil. Copepoda, Cladocera and Rotifera, as well as the three groups combined, showed different patterns from that predicted by MTE, with b values equal to 0.871, 0.516, 0.720 and 0.901, respectively. Temperature explains 12.7% of the richness of Copepoda, 5.3% of Cladocera, 6.7% of Rotifera, and 11.4% of all zooplankton groups together. Several studies have shown that the MTE does not apply to many terrestrial groups, perhaps because the model does not consider variances generated by other factors such as environmental spatial range, body size and other variables. The present study confirms this point of view, expanding it to continental aquatic invertebrates as well. macroecology; biodiversity; Copepoda; Cladocera; Rotífera; temperature gradients

19.
Acta sci., Biol. sci ; 34(1): 69-75, Jan.-Mar. 2012. tab, graf, mapas
Article in English | LILACS, VETINDEX | ID: biblio-868061

ABSTRACT

Several ecological hypotheses try to explain geographical patterns in biodiversity. The Metabolic Theory of Ecology (MTE) predicts that temperature is the main determinant of richness patterns for ectothermic organisms and that the relationship between richness (lnS) and temperature (1/kT) is a linear relationship with angular coefficient (b) near -0.65. This study tested the MTE for continental zooplankton diversity in 63 lakes in Brazil. Copepoda, Cladocera and Rotifera, as well as the three groups combined, showed different patterns from that predicted by MTE, with b values equal to 0.871, 0.516, 0.720 and 0.901, respectively. Temperature explains 12.7% of the richness of Copepoda, 5.3% of Cladocera, 6.7% of Rotifera, and 11.4% of all zooplankton groups together. Several studies have shown that the MTE does not apply to many terrestrial groups, perhaps because the model does not consider variances generated by other factors such as environmental spatial range, body size and other variables. The present study confirms this point of view, expanding it to continental aquatic invertebrates as well.


Várias hipóteses ecológicas tentam explicar os padrões geográficos de biodiversidade. A Teoria Metabólica da Ecologia (Metabolic Theory of Ecology - MTE) prediz que a temperatura é o principal determinante dos padrões de riqueza de organismos ectotérmicos e que a relação entre riqueza (lnS) e temperatura (1/kT) é uma reta com coeficiente angular (b) próximo a -0,65. O presente estudo testou a MTE para a diversidade zooplanctônica continental em 63 lagos brasileiros. Copepoda, Cladocera e Rotifera, assim como os três grupos analisados em conjunto, apresentaram padrões diferentes do previsto pela MTE, com os valores de b iguais a 0,871; 0,516; 0,720 e 0,901, respectivamente. A temperatura explicou 12,7% da riqueza de Copepoda, 5,3% de Cladocera, 6,7% de Rotifera e 11,4% do zooplâncton total. Diversos trabalhos têm demonstrado que a MTE não se aplica a muitos grupos terrestres, talvez porque o modelo não prevê desvios ocasionados por fatores como a variação espacial no ambiente, o tamanho corporal e outras variáveis. O presente trabalho corrobora este ponto de vista, expandindo-o também para invertebrados aquáticos continentais.


Subject(s)
Animals , Rotifera , Temperature , Cladocera , Copepoda , Biodiversity , Ecology
20.
Biol. Res ; 44(1): 63-67, 2011. ilus
Article in English | LILACS | ID: lil-591865

ABSTRACT

Proliferation and cell fate determination in the developing embryo are extrinsically regulated by multiple interactions among diverse secreted factors, such as Sonic Hedgehog (SHh), which act in a concentration-dependent manner. The fact that SHh is secreted as a lipid-modified protein suggests the existence of a mechanism to regulate its movement across embryonic fields. We have previously shown that heparan sulfate proteoglycans (HSPGs) are required for SHh binding and signalling. However, it was not determined which specific HSPG was responsible for these functions. Here we evaluated the contribution of perlecan on SHh localization and activity. To understand the mechanism of action of perlecan at the cellular level, we studied the role of perlecan-SHh interaction in SHh activity using both cell culture and biochemical assays. Our findings show that perlecan is a crucial anchor and modulator of SHh activity acting as an extracellular positive regulator of SHh.


Subject(s)
Animals , Humans , Mice , Rats , Brain/drug effects , Heparan Sulfate Proteoglycans/pharmacology , Signal Transduction/drug effects , Brain/metabolism , Chromatography, Gel , Fibroblasts/drug effects , Fibroblasts/metabolism , Gene Expression Regulation, Developmental , Hedgehog Proteins/metabolism , Heparan Sulfate Proteoglycans/isolation & purification , Heparan Sulfate Proteoglycans/metabolism , Heparan Sulfate Proteoglycans/physiology , Immunohistochemistry
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