Plasticity and rectangularity in survival curves

Living systems inevitably undergo a progressive deterioration of physiological function with age and an increase of vulnerability to disease and death. To maintain health and survival, living systems should optimize survival strategies with adaptive interactions among molecules, cells, organs, individuals, and environments, which arises plasticity in survival curves of living systems. In general, survival dynamics in a population is mathematically depicted by a survival rate, which monotonically changes from 1 to 0 with age. It would be then useful to find an adequate function to describe complicated survival dynamics. Here we describe a flexible survival function, derived from the stretched exponential function by adopting an age-dependent shaping exponent. We note that the exponent is associated with the fractal-like scaling in cumulative mortality rate. The survival function well depicts general features in survival curves; healthy populations exhibit plasticity and evolve towards rectangular-like survival curves, as examples in humans or laboratory animals

A SURVEY OF TRANSCRIPTS EXPRESSED SPECIFICALLY IN ROOT-NODULES OF BROADBEAN (VICIA-FABA L)

PERLICK AM, Pühler A. A SURVEY OF TRANSCRIPTS EXPRESSED SPECIFICALLY IN ROOT-NODULES OF BROADBEAN (VICIA-FABA L). PLANT MOLECULAR BIOLOGY. 1993;22(6):957-970.More than 600 potentially nodule-specific clones have been detected by differential hybridization of a broadbean cDNA library constructed from root nodule poly(A)+ RNA. These isolated cDNAs belong to at least 28 different clone groups containing cross-hybridizing sequences. The number of clones within a clone group varies from about 200 to only one single clone. Northern hybridization experiments revealed nodule-specific transcripts for 14 clone groups and markedly nodule-enhanced transcripts for another 7 clone groups. Sequence homologies indicate that three transcript sequences code for different leghemoglobins. Two other transcripts encode a nodule-specific sucrose synthase and a nodule-enhanced asparagine synthetase, respectively. Four deduced gene products are proline-rich, two of them being the homologues of PsENOD2 and PsENOD12. The third proline-rich protein (PRP) is composed of similar amino acid repeats as the nodule-specific PsENOD12 but is expressed in nodules and roots in comparable amounts. The fourth PRP is a nodule-enhanced extensin-type protein built up by Ser-Pro4 repeats. Two further nodule-specific transcripts encode gene products showing some similarity to structural glycine-rich proteins. Additionally, transcripts could be identified for broadbean homologues of the nodulins MsNOD25, PsENOD3 and PsENOD5 and transcripts specifying a nodule-enhanced lipoxygenase and a translation elongation factor EF-1alpha, which is expressed in all broadbean tissues tested

Have lichenized fungi delivered promising anticancer small molecules?

This review, covering the literature from 1844 to present (end 2017), probes questions concerning small molecule metabolites derived from lichens (lichenized fungi) and their impact in terms of providing compounds with significant promise in oncology. The review gives an overview of lichenized fungi and summarizes the classes of compounds obtained as metabolites from these organisms. A definition of what characteristics an actual “promising” anticancer compound should possess is also delineated. The review reports a brief overview on human cancer and then goes into depth in listing compounds with so-called “anticancer properties” that have been isolated from lichenized fungi, according to their small molecule structural classes. Five “most promising” compounds are discussed in-depth, also considering the possibility of obtaining sufficient amounts for further investigations