17 research outputs found
An interlaboratory study of TEX86 and BIT analysis of sediments, extracts and standard mixtures.
Two commonly used proxies based on the distribution of glycerol dialkyl glycerol tetraethers (GDGTs) are the TEX86 (TetraEther indeX of 86 carbon atoms) paleothermometer for sea surface temperature reconstructions and the BIT (Branched Isoprenoid Tetraether) index for reconstructing soil organic matter input to the ocean. An initial round-robin study of two sediment extracts, in which 15 laboratories participated, showed relatively consistent TEX86 values (reproducibility ±3-4°C when translated to temperature) but a large spread in BIT measurements (reproducibility ±0.41 on a scale of 0-1). Here we report results of a second round-robin study with 35 laboratories in which three sediments, one sediment extract, and two mixtures of pure, isolated GDGTs were analyzed. The results for TEX86 and BIT index showed improvement compared to the previous round-robin study. The reproducibility, indicating interlaboratory variation, of TEX86 values ranged from 1.3 to 3.0°C when translated to temperature. These results are similar to those of other temperature proxies used in paleoceanography. Comparison of the results obtained from one of the three sediments showed that TEX86 and BIT indices are not significantly affected by interlaboratory differences in sediment extraction techniques. BIT values of the sediments and extracts were at the extremes of the index with values close to 0 or 1, and showed good reproducibility (ranging from 0.013 to 0.042). However, the measured BIT values for the two GDGT mixtures, with known molar ratios of crenarchaeol and branched GDGTs, had intermediate BIT values and showed poor reproducibility and a large overestimation of the "true" (i.e., molar-based) BIT index. The latter is likely due to, among other factors, the higher mass spectrometric response of branched GDGTs compared to crenarchaeol, which also varies among mass spectrometers. Correction for this different mass spectrometric response showed a considerable improvement in the reproducibility of BIT index measurements among laboratories, as well as a substantially improved estimation of molar-based BIT values. This suggests that standard mixtures should be used in order to obtain consistent, and molar-based, BIT values
Salmonella typhimurium infection triggers dendritic cells and macrophages to adopt distinct migration patterns in vivo
The presence of an anti-bacterial T cell response and evidence of bacterial products in inflamed joints of reactive arthritis patients suggests an antigen transportation role in this disease for macrophages and dendritic cells. We have investigated the functional properties and in vivo migration of macrophages and DC after infection with Salmonella enterica serovar Typhimurium (S. typhimurium). BM-derived macrophages and DC displayed enhanced expression of costimulatory molecules (CD40 and CD86) and increased production of pro-inflammatory cytokines (TNF-alpha, IL-6 and IL-12p40) and nitric oxide after infection. Upon adoptive transfer into mice, infected DC migrated to lymphoid tissues and induced an anti-Salmonella T cell response, whereas infected macrophages did not. Infection of DC with S. typhimurium was associated with strong up-regulation of the chemokine receptor CCR7 and acquisition of responsiveness to chemokines acting through this receptor. Moreover, S. typhimurium-infected CCR7-deficient DC were unable to migrate to lymph nodes after adoptive transfer, although they did reach the spleen. Our data demonstrate distinct roles for macrophages and DC as antigen transporters after S. typhimurium infection and a dependence on CCR7 for migration of DC to lymph nodes after bacterial infection
Multichannel raman scattering: Comparison of an intensified linear diode array and an ICCD detector
Recombinant inbreeding in mice reveals thresholds in embryonic corpus callosum development
Influence of elevated pulmonary vascular resistance on the relationship between central venous pressure and pulmonary artery occluded pressure following cardiopulmonary bypass
Multiplex PCR assay for detection of human interferon alpha2b gene in transgenic plants
During the last decade interferons are regarded as potent candidates for generation of plant-based edible vaccines because of broad spectrum of antiviral activities and adjuvant properties. Establishment and certification of numerous interferon producing plant systems requests development of fast and efficient multiplex PCR protocol for the transgene detection in GM plants. Here we represent a protocol for simultaneous amplification in one assay of fragments of hIFN alpha 2b gene and two control genes, namely virD1 of Agrobacterium tumefaciens and conservative region of plant actin gene.В последнее десятилетие интерфероны рассматриваются как перспективные кандидаты для получения из растений в виде съедобных вакцин, поскольку обладают широким спектром антивирусной активности и адъювантными свойствами. Создание и сертификация многочисленных растительных систем, продуцирующих рекомбинантный интерферон, делают актуальной разработку быстрого и эффективного протокола мультиплексной ПЦР для определения данного трансгена в генетически модифицированных растениях. В настоящей публикации мы приводим метод детекции гена человеческого интерферона альфа-2b в трансгенных растениях с помощью совместной амплификации в ходе одной реакции фрагментов гена hINTα2b и двух контрольных генов, virD1 Agrobacterium tumefaciens и консервативного участка гена актина растений.В останнє десятиліття інтерферони розглядаються як перспективні кандидати для отримання з рослин у вигляді їстівних вакцин оскільки, вони мають широкий спектр антивірусної активності й ад’ювантні властивості. Створення і сертифікація численних рослинних систем, які накопичують рекомбінантний інтерферон, роблять актуальною розробку швидкого й ефективного протоколу мультиплексної ПЛР для визначення даного трансгена в генетично модифікованих рослинах. В цій публікації ми наводимо метод детекції гена людського інтерферону альфа-2b у трансгенних рослинах за допомогою сумісної ампліфікації в ході однієї реакції фрагментів гена hINTα2b і двох контрольних генів, virD1 Agrobacterium tumefaciens і консервативної ділянки гена актину рослин