Enhanced expression of the β II subspecies of protein kinase C in differentiating erythroleukemia cells

Polyclonal antipeptide antibodies which recognize selected isozymes (α, β I, β II, and γ) of the protein kinase C family were used to identify specific subspecies in undifferentiated Friend erythroleukemia cells and in cells triggered to differentiate with hexamethylene bisacetamide. The β II isozyme of protein kinase C was the primary isozyme expressed and its abundance was significantly increased (P < 0.05) in differentiated cells. Differences in immunostaining between control and experimental groups were objectively quantitated by determining percentage transmission of light through cells based on color threshold rather than gray intensity levels. Staining was localized to the cytoplasm predominantly in differentiated cells, whereas nuclei stained more intensely in undifferentiated cells. These results provide immunocytochemical evidence to support the hypothesis that changes in the expression of the β II subspecies of protein kinase C are essential to the programmed maturation of differentiating Friend erythroleukemia cells.     

Proposed guidelines to evaluate scientific validity and evidence for genotype-based dietary advice

Nutrigenetic research examines the effects of inter-individual differences in genotype on responses to nutrients and other food components, in the context of health and of nutrient requirements. A practical application of nutrigenetics is the use of personal genetic information to guide recommendations for dietary choices that are more efficacious at the individual or genetic subgroup level relative to generic dietary advice. Nutrigenetics is unregulated, with no defined standards, beyond some commercially adopted codes of practice. Only a few official nutrition-related professional bodies have embraced the subject, and, consequently, there is a lack of educational resources or guidance for implementation of the outcomes of nutrigenetic research. To avoid misuse and to protect the public, personalised nutrigenetic advice and information should be based on clear evidence of validity grounded in a careful and defensible interpretation of outcomes from nutrigenetic research studies. Evidence requirements are clearly stated and assessed within the context of state-of-the-art ‘evidence-based nutrition’. We have developed and present here a draft framework that can be used to assess the strength of the evidence for scientific validity of nutrigenetic knowledge and whether ‘actionable’. In addition, we propose that this framework be used as the basis for developing transparent and scientifically sound advice to the public based on nutrigenetic tests. We feel that although this area is still in its infancy, minimal guidelines are required. Though these guidelines are based on semi-quantitative data, they should stimulate debate on their utility. This framework will be revised biennially, as knowledge on the subject increases.     

Special Issue: 2019 Consortium for Trans-Pyrenean Investigations on Obesity and Diabetes

Journal of Physiology and Biochemistry - This Special Issue of the Journal of Physiology and Biochemistry contains 6 contributions that exemplify the advances obtained by the mini-network entitled...     

Management of interruptions in radiotherapy treatments: Adaptive implementation in high workload sites

Owing to predictable or unpredictable causes, interruptions may arise during therapy. On average, the extension of fractionated radiotherapy treatments is prone to be delayed by several weeks and interruptions can come up extending overall treatment time (OTT). Clonogenic cells of aggressive tumors might benefit from this situation, modifying local control (LC).Preserving treatment quality in radiotherapy is an essential issue for the treatment outcome, and our institution is increasingly concerned about this line of work.Establishing some objective criteria to schedule patients that have suffered interruptions along their treatments is of capital importance and not a trivial issue. Publications strongly encourage departments to minimize the effect of lag periods during treatments. Therefore, in July 2017, our facility implemented the so called ‘Protocol to Manage Interruptions in Radiotherapy’, based on a scoring system for patient categorization that considers not only histology but also associated comorbidity and sequence of the therapy.     

Agar-Screen Specimen Carrier for Bulk Processing of Biopsy Materials for Electron Microscopy

A specimen carrier for processing large numbers of biopsy materials for epoxy embedding and electron microscopy is described. Commercially available 18-mesh stainless steel or 16-mesh aluminum wire screening is used. The screening is cut into 1 × 3-inch strips. One corner is snipped off for orientation purposes. Four drops of warm 4% agar is placed on a prewarmed standard microscopic glass slide. A thin agar support film is formed on the bottom side of the horizontally held wire screen by lightly running it against the agar. Tissue blocks trimmed to 1 mm³ are blotted on filter paper and placed in a prearranged order on the top surface of the support film. A thin top coating of agar is applied on the specimen by touching it with the tip of a pasteur pipette containing warm 4% agar. The agar-screen unit with the mounted specimens is stabilized in 4% buffered formalin and rinsed with Sorenson's phosphate buffer, pH 7.4, with 6.8% sucrose. It is then processed as a unit through routine osmium tetroxide postfixation, alcohol dehydration, and Epon 812 infiltration. The tissue blocks are plucked off the agar support film with fine-tipped tweezers and embedded in individual capsules. No difficulty in thin sectioning was encountered and examination of the sections under the electron microscope showed good infiltration by the epoxy resin.     

Agential autonomy and biological individuality

What is a biological individual? How are biological individuals individuated? How can we tell how many individuals there are in a given assemblage of biological entities? The individuation and differentiation of biological individuals are central to the scientific understanding of living beings. I propose a novel criterion of biological individuality according to which biological individuals are autonomous agents. First, I articulate an ecological–dynamical account of natural agency according to which, agency is the gross dynamical capacity of a goal-directed system to bias its repertoire to respond to its conditions as affordances. Then, I argue that agents or agential dynamical systems can be agentially dependent on, or agentially autonomous from, other agents and that this agential dependence/autonomy can be symmetrical or asymmetrical, strong or weak. Biological individuals, I propose, are all and only those agential dynamical systems that are strongly agentially autonomous. So, to determine how many individuals there are in a given multiagent aggregate, such as multicellular organism, a colony, symbiosis, or a swarm, we first have to identify how many agential dynamical systems there are, and then what their relations of agential dependence/autonomy are. I argue that this criterion is adequate to the extent that it vindicates the paradigmatic cases, and explains why the paradigmatic cases are paradigmatic, and why the problematic cases are problematic. Finally, I argue for the importance of distinguishing between agential and causal dependence and show the relevance of agential autonomy for understanding the explanatory structure of evolutionary developmental biology.     

Enlargement of fibrous roots inIpomoea sectionBatatas (Convolvulaceae)

The bank of sweet potato germplasm at the International Potato Center (CIP) in Lima, Peru, is made up of cultivated germplasm [Ipomoea batatas (L.) Lam.] and wild germplasm collected in Latin America and the Caribbean. In the wild germplasm sectionBatatas is included because of its genetic importance in relation to its phylogenetic affinity with the cultivated sweet potato. In our study we have included 11 wild species of the section to identify and determine the primary factors that influence the enlargement of fibrous roots under greenhouse conditions. Thus, the study was divided into two sequential phases: a) identification of wild species with thickened fibrous roots; b) determination of the primary factors that influence the thickening of fibrous roots. The first phase began between 197 and 593 days after planting the 11 species by using a visual evaluation of the roots according to the gradual scale: 0 = fibrous roots; 1 = slightly thickened; 2 = moderately thickened; 3 = thickened; 4 = very thick. As a result four species were identified in categories three and four (I. batatas, I. cordato-triloba, I. tiliacea, andI. ramosissima). The second phase was begun between 123 and 669 days after planting of nine species identified with some category of enlargement according to an evaluation with a gradual quantified scale: 0 = <1.45 mm; 1 = 1.45–3.99 m; 2 = 4.0–6.99 mm; 3 = 7.0–9.0 mm; 4 = >9.0 mm. In this phase, two physiological factors were identified (vegetative period and volume of substrate) and a genetic factor (level of ploidy), which directly influence the thickening of fibrous roots. Considering the four species identified with thickened fibrous roots in categories three and four in the two phases of the study [I. batatas (4x),I. tiliacea (4x),I. cordato-triloba (2x) andI. ramosissima (2x)], we propose a plan for the use of wild germplasm in a program of systematic genetic improvement of the sweet potato.