Obligate ectosymbionts increase the physiological resilience of a scleractinian coral to high temperature and elevated pCO2

Coral Reefs - Invertebrate ectosymbionts within the coralla of scleractinians enhance host fitness through protection from corallivores and nutrient addition. Here, we explore the ectosymbiotic...     

Toward Enhanced MIQE Compliance: Reference Residual Normalization of qPCR Gene Expression Data

Normalization of fluorescence-based quantitative real-time PCR (qPCR) data varies across quantitative gene expression studies, despite its integral role in accurate data quantification and interpretation. Identification of suitable reference genes plays an essential role in accurate qPCR normalization, as it ensures that uncorrected gene expression data reflect normalized data. The reference residual normalization (RRN) method presented here is a modified approach to conventional 2^−ΔΔCtqPCR normalization that increases mathematical transparency and incorporates statistical assessment of reference gene stability. RRN improves mathematical transparency through the use of sample-specific reference residuals (RR_i) that are generated from the mean C_t of one or more reference gene(s) that are unaffected by treatment. To determine stability of putative reference genes, RRN uses ANOVA to assess the effect of treatment on expression and subsequent equivalence-threshold testing to establish the minimum permitted resolution. Step-by-step instructions and comprehensive examples that demonstrate the influence of reference gene stability on target gene normalization and interpretation are provided. Through mathematical transparency and statistical rigor, RRN promotes compliance with Minimum Information for Quantitative Experiments and, in so doing, provides increased confidence in qPCR data analysis and interpretation.     

A Metabolic Basis for Endothelial-to-Mesenchymal Transition

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Rhythmic settling induced by temperature cycles in continuously-stirred autotrophic cultures of Euglena gracilis (Z strain)

Summary Temperature cycles which produced synchrony of cell division in autotrophic Euglena (preceding paper, Terry and Edmunds, 1970) usually also evoked a cellular settling rhythm. The rhythm was expressed as a recurrent cycle of cell attachment to culture-vessel surfaces, with nearly the same phase angle to each of the different temperature cycles. Attachment occurred in cultures stirred rapidly enough for thorough mixing of the cell suspension, but it was possible to prevent attachment by increased agitation. The settling rhythm was entrained by temperature cycles with periods shorter than the minimum period length required to phase cell division, but the rhythm also persisted with a circadian period at constant temperature in continuous light following entrainment by 12,12 hr temperature cycles. The rhythm appeared in stationary-phase cultures exposed to either cold-synchronizing or heat-synchronizing temperature cycles, and also in growth-phase cultures exposed to cold-synchronizing cycles. The settling rhythm was generally not observable in heat-synchronized growth-phase cultures although it often appeared in the same cultures as they approached the stationary phase.This work is derived from a dissertation submitted to the Department of Biological Sciences of the State University of New York at Stony Brook by OzTerry in partial fulfillment of the requirements for the degree of Doctor of Philosophy. It was supported in part by a National Science Foundation Cooperative Graduate Fellowship to 0. Terry and in part by National Science Foundation research grants GB-4140 and GB-6892 and by State University of New York Research Foundation Grant-in-Aid 31-7150A to L. Edmunds.     

The hidden dynamics of low coral cover communities

Our study presents a low-cost method (no expensive hardware platforms required) of quantified biomonitoring based on computer image analysis. The negative influence of toxins on surface waters was analysed. The method was verified on widespread freshwater macrophyte Lemna minor to test populations treated with non-ionic detergents. We showed that the proposed automated bioassay has a broad applicability in assessing the negative impacts of aquatic toxicants. This approach enabled fast and precise evaluation of the morphometric parameters of the duckweed test population. We observed that growth rate of L. minor reacts to non-ionic detergents, which is reflected by the change in the surface area. The decrease in the growth of L. minor was revealed at high doses of detergents. This test proved to be highly useful, because it is well repeatable and fast in its implementation. Unlike classical bioassays, the proposed test allows the elimination of measurement errors, resulting from observers’ subjectivity.     

Serum keratan sulphate levels rise in rheumatoid arthritis patients, but fall in ankylosing spondylitis patients compared with normal controls

Serum levels of keratan sulphate (KS) were found to be significantly elevated in patients with destructive and predominantly seronegative rheumatoid arthritis (RA) compared with a control population. Levels in RA did not correlate with clinical or laboratory indices of joint activity or damage. Conversely levels were depressed in ankylosing spondylitis (AS) compared with controls.     

Perspective: human contact patterns and the spread of airborne infectious diseases.

Networks of social contacts channel the transmission of airborne infections. Emerging insights from fields of science as diverse as mathematics, population biology and the social sciences are beginning to reveal how the contact pattern of the hosts determines the spread and evolution of airborne infectious agents.