Defects in leaf epidermis of Arabidopsis thaliana plants with CDKA;1 activity reduced in the shoot apical meristem

In Arabidopsis thaliana, like in other dicots, the shoot epidermis originates from protodermis, the outermost cell layer of shoot apical meristem. We examined leaf epidermis in transgenic A. thaliana plants in which CDKA;1.N146, a negative dominant allele of A-type cyclin-dependent kinase, was expressed from the SHOOTMERISTEMLESS promoter, i.e., in the shoot apical meristem. Using cleared whole mount preparations of expanding leaves and sequential in vivo replicas of expanding leaf surface, we show that dominant-negative CDKA;1 expression results in defects in epidermis continuity: loss of individual cells and occurrence of gaps between anticlinal walls of neighboring pavement cells. Another striking feature is ingrowth-like invaginations of anticlinal cell walls of pavement cells. Their formation is related to various processes: expansion of cells surrounding the sites of cell loss, defected cytokinesis, and presumably also, the actual ingrowth of an anticlinal cell wall. The mutant exhibits also increased variation in cell size and locally reduced waviness of anticlinal walls of pavement cells. These unusual features of leaf epidermis phenotype may shed a new light on our knowledge on morphogenesis of jigsaw puzzle-shaped pavement cells and on the CDKA;1 role in regulation of plant development via influence on cytoskeleton and plant cell wall

Epiderma liścia - metody analizy wzrostu i kształtu komórek

Fascination with the construction of biological structures and a desire to explain their function have been a goal of researchers for centuries. Certainly their in-spiration increased when Robert Hook observed plant cells using a microscope 350 years ago. Nowadays, thanks to technological progress, biologists can study the phenomena and relationships of their interest using many different methods allowing them to learn about structures and functions of cells. These methods com-bine the achievements of genetic engineering, molecular biology, physics (including optics) with advanced computer science, allowing quick analysis and visualiza-tion of results in an interesting way. Currently the plant cell may have features “designed” by the researcher. For example, the commonly used transgenic lines allow in vivo observation of specific cell structures without the need for laborious material preparation (e.g. fixing and staining cell structures). Today researchers can also use different magnifications; from macroscopic, through microscopic to nanoscopic ones. Digital technology and constantly increasing computing power enable cell visualization in various dimensions as well as creating simulations and computer models. The purpose of this monograph is to present selected contemporary methods of plant cells’ visualization and analysis using epidermis as an example. The book is directed to a wide range of students interested in developmental biology. The first part focuses on the diversity of shapes of pavement cells of epidermis – the tissue important for morphogenesis and organ protection. This section describes methods enabling observation and analysis of plant cellular structures. The second part presents how to use microscopic techniques such as fluorescence microscopy, laser scanning confocal microscopy and scanning electron microscopy together with computer programs for visualization and quantitative analysis of cell shape and for calculations of epidermal cell growth

Metabolic surgery in zucker rats influenced miRNA, caveolin-1 expression and lipid metabolism

Aims: A transposition of the long segment of distal ileum in obese Zucker rats improved glucose tolerance 6 months after IT. It was undertaken to compare the gene expression of miRNA-103, -107 and caveolin-1 in the liver of euglycemic groups of IT relative to SHAM operated rats. Main methods: Obese, male Zucker rats underwent either transposition of 50% distal ileum or sham surgery. For determining the gene expression, the Real-Time PCR for caveolin-1 and miRNA-103, -107 was performed. Plasma concentrations of LDL, HDL, TG and total cholesterol were measured with enzymatic colorimetric assays after optimization procedure. Key findings: The Cav-1 expression in liver tissue after ileal transposition was 1.22 times higher compared to the SHAM group (SHAM median 63.58, min 41.3, max 82.4; IT median 77.35, min 60.8, max 95.41, p < 0.001). miRNA-107 expression was significantly downregulated by 0.6-fold in the IT group compared to the SHAM group (SHAM median 507.51, min 236.42, max 721.29; IT median 355.2, min 278.15, max 478.15, p < 0.015. The level of TG was significantly higher after IT surgery (SHAM median 115, min 96, max 143; IT median 153, min 115, max 162, p = 0.001). The total cholesterol plasma levels decreased after IT (SHAM median 178, min 161, max 183; IT median 128, min 103, max 114, p < 0.000001). The LDL plasma level in IT was two-fold lower than in the SHAM (SHAM median 117, min 68, max 151; IT median 58, min 45, max 61, p < 0.000001). Significance: The transposition of 50% of the distal ileum lead to an increase in caveolin-1 and reduction in miR-107 expression compared to those of SHAM group. Endogenous miR-107 is more involved in regulation of the functions of insulin-target liver tissue than miRNA-103. Reduced LDL and cholesterol plasma levels suggest positive effects on lipid metabolism in long-term observations. The present study is the first to show a lack of IT effect regarding triglycerides six months after surgery

Public, patient and carers’ views on palliative and end‐of‐life care in India: a systematic review

Aim To systematically review the existing evidence on the Indian public, patient and carers’ perspectives on palliative and end‐of‐life care. Background With a growing population of terminally ill people across the world, there is also an increasing awareness among international health policy makers of the need to improve the quality of life for terminally ill patients. Understanding service users’ (patients, family and public) perspectives is crucial in developing and sustaining successful community‐centred palliative nursing policies and service models especially in countries like India with diverse population. Methods An integrative review was performed on five databases, using hand searches of key journals and reference citation tracking for empirical studies published in English from 1990 to 2015. A thematic analysis framework was used to analyse and identify key themes. Results Analysis of the six eligible studies revealed five themes. Themes describe how social, economic, cultural, religious, spiritual and traditional factors influenced the palliative and end‐of‐life care perspectives and experiences among Indians. They also illustrated preferences relating to place of care, as well as benefits and challenges of family caregiving during the last days of life. Conclusions Although we found minimal evidence on user perspectives, nurses need to aware of those unique components of context‐specific palliative and end‐of‐life care practices in India – socioeconomic, cultural and religious factors – on their nursing encounters. Nurses need to advocate same in policy development to enable accessibility and utility of palliative and end‐of‐life care services, which are scant in India. Implications for nursing and health policy Nurses can be central in gathering the contextual evidence that advocate users’ perspectives to inform further studies and national palliative care policies in India. Emerging policies in nursing education need to focus on integrating family‐centred palliative and end‐of‐life care within curricula, whereas nursing practice may promote nurse‐led community models to address the patchy palliative and end‐of‐life service provision in India