Characterization of lipoprotein supplement and influence of its oxidized lipid content on cell culture performance and monoclonal antibody production by a SP2/0 hybridoma cell line

A challenging aspect with the use of the Sp2/0 hybridoma cell line in commercial manufacturing processes of recombinant therapeutic proteins is their exogenous lipids requirement for cell proliferation and optimal protein secretion. Lipids are commonly provided to the culture using serum or serum-derivatives, such as lipoprotein supplement. The batch-to-batch variability of these non-chemically defined raw-materials is known to impact cell culture process performance. Lipoprotein supplement variability and its impact on fed-batch production of a recombinant monoclonal antibody (mAb) expressed in Sp2/0 cells were studied using 36 batches from the same vendor. Several batches were associated with early viability drops leading to low process performance during fed-batch production. Increased caspase-3 activity (an indicator of apoptosis) was correlated to viability drops when low-performing batches were used. Addition of an antioxidant to the culture limited the increase in caspase-3 activity. Physicochemical characterization of batches confirmed that lipoproteins are mainly composed of lipids and proteins; no clear correlation between low-performing batches and lipoprotein supplement composition was observed. Controlled lipoprotein oxidation leads to lipoprotein solution browning, increasing absorbance at 276 nm and results in poor process performance. Because low-performing batches absorb more at 276 nm than other batches, oxidized lipids were suspected to be the root cause of low-performing batches. This study increased the understanding of lipoprotein supplement composition, its sensitivity to oxidation and its impact on process performance.     

Comparing Bioenergy Production Sites in the Southeastern US Regarding Ecosystem Service Supply and Demand

Biomass for bioenergy is debated for its potential synergies or tradeoffs with other provisioning and regulating ecosystem services (ESS). This biomass may originate from different production systems and may be purposefully grown or obtained from residues. Increased concerns globally about the sustainable production of biomass for bioenergy has resulted in numerous certification schemes focusing on best management practices, mostly operating at the plot/field scale. In this study, we compare the ESS of two watersheds in the southeastern US. We show the ESS tradeoffs and synergies of plantation forestry, i.e., pine poles, and agricultural production, i.e., wheat straw and corn stover, with the counterfactual natural or semi-natural forest in both watersheds. The plantation forestry showed less distinct tradeoffs than did corn and wheat production, i.e., for carbon storage, P and sediment retention, groundwater recharge, and biodiversity. Using indicators of landscape composition and configuration, we showed that landscape planning can affect the overall ESS supply and can partly determine if locally set environmental thresholds are being met. Indicators on landscape composition, configuration and naturalness explained more than 30% of the variation in ESS supply. Landscape elements such as largely connected forest patches or more complex agricultural patches, e.g., mosaics with shrub and grassland patches, may enhance ESS supply in both of the bioenergy production systems. If tradeoffs between biomass production and other ESS are not addressed by landscape planning, it may be reasonable to include rules in certification schemes that require, e.g., the connectivity of natural or semi-natural forest patches in plantation forestry or semi-natural landscape elements in agricultural production systems. Integrating indicators on landscape configuration and composition into certification schemes is particularly relevant considering that certification schemes are governance tools used to ensure comparable sustainability standards for biomass produced in countries with variable or absent legal frameworks for landscape planning.     

Lysosomal lipoprotein processing in endothelial cells stimulates adipose tissue thermogenic adaptation

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Grueneberg Glomeruli in the Olfactory Bulb are Activated by Odorants and Cool Temperature

Neurons of the Grueneberg ganglion respond to cool temperatures as well as to distinct odorants and extend axonal processes to the olfactory bulb of the brain. Analyses of transgenic mice, in which Grueneberg ganglion neurons and their axons are labeled, revealed that these axons innervated nine distinct glomeruli distributed in a characteristic topographical pattern in dorsal, lateral, ventral, and medial regions of rather posterior areas in the bulb. To assess activation of these glomeruli (hereinafter designated as Grueneberg glomeruli) upon stimulation of Grueneberg ganglion neurons, mice were exposed to the odorant 2,3-dimethylpyrazine (2,3-DMP) and the expression of the activity-dependent marker c-Fos in juxtaglomerular cells of the relevant glomeruli was monitored. It was found that all of these glomeruli were activated, irrespective of their localization in the bulb. To verify that the activation of juxtaglomerular cells in Grueneberg glomeruli was indeed based on stimulation of Grueneberg ganglion neurons, the 2,3-DMP-induced responses in these glomeruli were investigated in mice lacking the cyclic nucleotide-gated channel CNGA3 which is critical for chemo- and thermosensory signal transduction in Grueneberg ganglion neurons. This approach revealed that elimination of CNGA3 led to a reduction of the odorant-induced activity in Grueneberg glomeruli, indicating that the activation of these glomeruli is based on a preceding stimulation of the Grueneberg ganglion. Analyzing whether Grueneberg glomeruli in the bulb might also process thermosensory information, it was found that upon exposure to coolness, Grueneberg glomeruli were activated. Investigating mice lacking CNGA3, the activation of these glomeruli by cool temperatures was attenuated.     

Illegitimate authorship and flawed procedures: Fundamental,formal criticisms of the Declaration of Helsinki

Some of the recent criticisms published during and after the last revision process of the Declaration of Helsinki are directed at its basic legitimacy. In this article we want to have a closer look at the two criticisms we consider to be the most fundamental. The first criticism questions the legitimate authorship of the World Medical Association to publish a document such as the Declaration. The second fundamental criticism we want to examine argues that the last revision process failed to meet the standards for fair, democratic procedures. Although both criticisms deny the formal legitimacy of the Declaration in the most fundamental way, they have never been addressed in detail in a single article. We refute most of the related arguments. However, acknowledging some of the points made, improvements for future revision processes and versions of the Declaration of Helsinki are outlined.     

Central projection of auditory receptors in the prothoracic ganglion of the bushcricket Psorodonotus illyricus (tettigoniidae): Computer-aided analysis of the end branch pattern

The projection patterns of morphologically and functionally identified auditory and auditory-vibratory receptor cells of receptor organs (the crista acustica and the intermediate organ) in the foreleg of the tettigoniid Psorodonotus illyricus, were investigated with combined recording and staining techniques, and subsequent histological examination and morphometric measurements. With the application of a computer program (AutoCAD), three-dimensional reconstructions of the axon end branches of receptor cells within the neuropile of the anterior Ring Tract (aRT) were made, in order to determine, the entire shape of each, the pattern and density of the end branches, and the positions of the target areas within the auditory neuropile. Clear differences for different functional types of receptors were found. 1994 John Wiley & Sons, Inc.