261 research outputs found
Microenvironmental regulation of the sinusoidal endothelial cell phenotype in vitro
Author Manuscript: 2010 June 23.Liver sinusoidal endothelial cells (LSECs) differ, both structurally and functionally, from endothelial cells (ECs) lining blood vessels of other tissues. For example, in contrast to other ECs, LSECs possess fenestrations, have low detectable levels of platelet endothelial cell adhesion molecule 1 expression, and in rat tissue, they distinctively express a cell surface marker recognized by the SE-1 antibody. These unique phenotypic characteristics seen in hepatic tissue are lost over time upon culture in vitro; therefore, this study sought to systematically examine the effects of microenvironmental stimuli—namely, extracellular matrix and neighboring cells, on the LSEC phenotype in vitro. In probing the role of the underlying extracellular matrix, we identified collagen I and collagen III as well as mixtures of collagen I/collagen IV/fibronectin as having a positive effect on LSEC survival. Furthermore, using a stable hepatocellular model (hepatocyte–fibroblast) we were able to prolong the expression of both SE-1 and phenotypic functions of LSEC such as factor VIII activity and AcLOL uptake in cocultured LSECs through the production of short-range paracrine signals. In the course of these experiments, we identified the antigen recognized by SE-1 as CD32b. Conclusion: Collectively, this study has identified several microenvironmental regulators of liver sinusoidal endothelial cells that prolong their phenotypic functions for up to 2 weeks in culture, enabling the development of better in vitro models of liver physiology and disease
PENGARUH KOMPOSISI MEDIA DAN FERTIGASI PUPUK ORGANIK TERHADAP KANDUNGAN BIOAKTIF DAUN TANAMAN KEMUNING (Murraya paniculata (L.) JACK) DI PEMBIBITAN
Kemuning (Murraya paniculata) dapat digunakan sebagai obat tradisional. Banyak penelitian mengenai fitofarmakologi kemuning tapi tidak pada penelitian mengenai budidaya. Penelitian dilaksanakan sejak Oktober 2011 sampai Maret 2012 di Gunung Batu, Bogor. Tujuan penelitian ini adalah untuk mengetahui pengaruh kombinasi komposisi media dan aplikasi fertigasi dengan pupuk organik terhadap kandungan bioaktif daun kemuning. Penelitian menggunakan analisis kualitatif fitokimia pada daun kemuning. Perlakuan yang diberikan komposisi media tanah latosol Darmaga + arang sekam padi (1:1) v/v tanpa fertigasi; komposisi media tanah latosol Darmaga + arang sekam padi + pupuk kandang kambing (1:1:1) v/v dan aplikasi fertigasi dengan kotoran kambing; komposisi media dengan tanah latosol Darmaga + arang sekam padi + pupuk kandang kambing (1:1:1) v/v dan aplikasi fertigasi dengan pupuk kandang kotoran ayam; komposisi media tanah latosol Darmaga + arang sekam padi + kotoran ayam (1:1:1 ) v/v dan aplikasi fertigasi dengan kotoran kambing; komposisi media tanah latosol Darmaga + arang sekam padi + kotoran ayam (1:1:1) v/v dan aplikasi fertigasi dengan pupuk kandang ayam. Konsentrasi yang digunakan untuk fertigasi yaitu satu kg pupuk organik per lima liter air, dengan dosis 60 ml per tanaman, dan diaplikasikan setiap dua minggu. Hasil penelitian analisis kualitatif fitokimia menunjukkan bahwa daun kemuning mengandung steroid yang paling tinggi, dan diikuti saponin, flavonoid, tanin, dan alkaloid
HUBUNGAN JUMLAH BUNGA, JUMLAH DAUN, JUMLAH ANAK DAUN, JUMLAH CABANG, DAN TINGGI TANAMAN TERHADAP PERTUMBUHAN BIBIT TANAMAN KEMUNING (Murraya paniculata (L.) Jack)
ABSTRACTThere is a problem that is frequently complained by the nursery which usually cultivated orange jessamine (Murraya paniculata (L.) Jack) from seed as a landscape plant. The problem is orange jessamine usually flowering although the size of the plants are still very small (about 5 cm) and even only has two leafs. These condition tends to be less favorable for the nursery because the orange jessamine grows slow because of vegetative growth was delayed due to the generative growth is underway. This study aims to see how important the presence of orange jessamine flowers in the nursery and how its relationship with branching, plant height, numberof leaves and number of leaflets. This research used a simple linear regression analysis and correlation of 150 orange jessamine plant seeds. The results showed only the correlation of the amount of flowers with plant height that has no significant correlation. Nevertheless, the presence of flowers in the nursery remains important because every increase in the number of flowers, there is also an increase in the number of branch, number of leaf, and number of leaflet.Keywords: Murraya paniculata (L.) Jack, rutaceae, flowers, landscape plants, plant nurser
Patrimonio cultural platense : El arte funerario, una vía para recuperar la identidad
El presente trabajo forma parte de una serie de investigaciones realizadas en el último año, investigaciones que apuntan, como objetivo final, a revalorizar el patrimonio cultural de la ciudad de la Plata.
Frente a un problema de alcance municipal como lo es la pérdida del patrimonio- cultural de la mencionada ciudad comenzamos por circunscribir nuestras investigaciones al tema del arte; más específicamente, del arte del Cementerio Municipal. Desde este punto de partida, intentamos rescatar la organización particular y el valor simbólico de la arquitectura urbana.
A través de la evaluación de conclusiones en trabajos previos de investigación, pudimos hallar una íntima vinculación entre el arte fúnebre y el edilicio de las partes restantes de la ciudad. Tal configuración respire un eclecticismo que es denominador común de la generación de la fundación de la ciudad, verdadero reflejo de la identidad de una época.Facultad de Ciencias Naturales y Muse
Host Cell Phosphatidylcholine Is a Key Mediator of Malaria Parasite Survival during Liver Stage Infection
During invasion, Plasmodium, the causative agent of malaria, wraps itself in a parasitophorous vacuole membrane (PVM), which constitutes a critical interface between the parasite and its host cell. Within hepatocytes, each Plasmodium sporozoite generates thousands of new parasites, creating high demand for lipids to support this replication and enlarge the PVM. Here, a global analysis of the total lipid repertoire of Plasmodium-infected hepatocytes reveals an enrichment of neutral lipids and the major membrane phospholipid, phosphatidylcholine (PC). While infection is unaffected in mice deficient in key enzymes involved in neutral lipid synthesis and lipolysis, ablation of rate-limiting enzymes in hepatic PC biosynthetic pathways significantly decreases parasite numbers. Host PC is taken up by both P. berghei and P. falciparum and is necessary for correct localization of parasite proteins to the PVM, which is essential for parasite survival. Thus, Plasmodium relies on the abundance of these lipids within hepatocytes to support infection.Seventh Framework Programme (European Commission) (Grant Agreement 311502)Fundacao para a Ciencia e a Tecnologia (Grant EXCL/IMI-MIC/0056/2012)Fundacao para a Ciencia e a Tecnologia (Grant PTDC/IMI-MIC/1568/2012
Assessing the use of marine protected areas by loggerhead sea turtles (Caretta caretta) tracked from the western Mediterranean.
Up to date 264 Marine Protected Areas (MPAs) have been declared in the western Mediterranean Sea. The management plans of 25 of these MPAs include the loggerhead sea turtle (Caretta caretta) as a priority species to protect. However, the actual use of these MPAs by the species remains unknown. Therefore, it is important to assess their contribution to loggerhead conservation in the area. To this end, satellite tracking data of 103 loggerhead turtles of varying sizes and life stages released in Spanish Mediterranean waters and Southern Tyrrhenian Sea over the 2003-2018 period were herein used. Home range and use of MPAs by tracked loggerhead turtles were analysed using post-processed state-space model locations. The tracked turtles visited several Mediterranean MPAs, but barely used them (mean percentage of monitoring time = 12.6 ± 18.2 %). There was very little overlap between turtle's core areas and tracks with the protected areas. Indeed, most of the core areas and high-density areas estimated (>85 %) were not included within any of the MPAs. Furthermore, less than 5 % of the Mediterranean MPAs were used by any tracked loggerhead sea turtles. Most of these MPAs have no protection measures that focus on this species. Loggerheads mainly use wide oceanic zones and international waters, which are difficult to protect. A high-use core area was identified for loggerhead turtles, located at the western waters of the Algerian Basin, an important fishing area outside any designated MPA and with no protection measures that focus on marine turtle conservation. We conclude that existing MPAs in the western Mediterranean may not contribute enough to loggerhead turtle conservation. We propose potential MPAs designations to be considered for loggerhead sea turtle conservation in the Mediterranean Sea at the Alboran Sea, the Algerian basin, the Northern area of the Strait of Sicily, Northeast Tunisian waters, waters around Malta, waters at the Tyrrhenian Sea and at the Ionian Sea
ASSOCIAÇÃO ENTRE A FRAÇÃO EXALADA DE ÓXIDO NÍTRICO E DADOS DA ESPIROMETRIA E O CONTROLE CLÍNICO DA ASMA EM CRIANÇAS E ADOLESCENTES
- …