A study on the factors that influence job satisfaction among lecturers in Universiti Utara Malaysia

Job satisfaction has been an increasingly researched field of study since the past research shown the important to the organization as a whole. Despite the increase in attention given to the study of workplace satisfaction, there is still question on the relationship and affects to the satisfaction. This study tries to identify the relationship between the salary, job stress, career promotion and working environment in the academic community towards job satisfaction of the lecturers. The current research has been conducted among 226 lecturers in Universiti Utara Malaysia (UUM). A questionnaire survey based research was used to collect data and analyzed using Pearson correlation and linear regression to identify the relationship and test the hypothesis. The findings of this study indicate, that there is a significant and positive relationship between salary, job stress, career promotion, working environment and job satisfaction. Job stress was found to be not significant in affecting the job satisfaction of lecturers

A histological study of oil palm (Elaeis guineensis) endosperm during seed development

Information on histological features of oil palm is scarce, especially on seed development. This study aims to examine the cell structure and anatomy of developing oil palm seed. The seeds were analysed by histochemical technique and light microscopy. At early developmental stages, a vacuole fluid-filled endosperm was formed. As the seed developed further, the enlargement of the endosperm size was observed accompanied by cellularisation. Cells were formed from the periphery towards the centre of the endosperm. Accumulation of storage reserves within the cells started at week 10 after anthesis. Polysaccharides were stored in the form of thickened walls whilst lipid and protein were stored in the cytoplasm. At late developmental stages, the endosperm cavity was fully cellularised and storage reserves accumulated within the entire cell. A small cylindrical embryo was seen embedded within the massive endosperm tissue. The endosperm functions as a nutrient reservoir for the embryo. This histological study of developing oil palm seeds provides information on the nature and anatomical changes in endosperm tissues as well as shedding light on the growing points of seed development

Biochemical characterisation during seed development of oil palm (Elaeis guineensis)

Developmental biochemical information is a vital base for the elucidation of seed physiology and metabolism. However, no data regarding the biochemical profile of oil palm (Elaeis guineensis Jacq.) seed development has been reported thus far. In this study, the biochemical changes in the developing oil palm seed were investigated to study their developmental pattern. The biochemical composition found in the seed differed significantly among the developmental stages. During early seed development, the water, hexose (glucose and fructose), calcium and manganese contents were present in significantly high levels compared to the late developmental stage. Remarkable changes in the biochemical composition were observed at 10 weeks after anthesis (WAA): the dry weight and sucrose content increased significantly, whereas the water content and hexose content declined. The switch from a high to low hexose/sucrose ratio could be used to identify the onset of the maturation phase. At the late stage, dramatic water loss occurred, whereas the content of storage reserves increased progressively. Lauric acid was the most abundant fatty acid found in oil palm seed starting from 10 WAA

A model for predicting flower development in Elaeis guineensis Jacq

The proper development of oil palm fruit is important as the source of oil is the fruit mesocarp and kernel. Prior to fruit formation, the development of flowers is therefore also important. Determination of the flower development stages in oil palm generally involves tedious histological analyses of each sampled inflorescence, making it a costly and inefficient way of gauging the developmental state. In this study, a statistical model was established from the association of physical or macroscopic measurement data to flower development, which was determined via histological analyses. The final reduced ordinal logistic regression model is a partial proportional odds model that uses inflorescence length and palm age as predictors to predict the flower development stage. The likelihood-ratio χ2 test suggested the model adequately fits the data (p<0.01). The model, with a prediction accuracy of 78.5%, can be used for selecting inflorescences of specific development stages from palms aged three to 10 years of field-planting. These stages can be further verified by histological analyses. This lowers the overall costs and time by reducing the number of samples requiring histological analysis prior to downstream studies

Stat3 is indispensable for damage-induced crypt regeneration but not for Wnt-driven intestinal tumorigenesis.

金沢大学ナノ生命科学研究所Signal transducer and activator of transcription 3 (Stat3) has been shown to play a role in intestinal regeneration and colitis-associated colon carcinogenesis. However, the role of Stat3 in the Wnt-driven sporadic intestinal tumorigenesis remains poorly understood. We examined the roles of Stat3 in intestinal regeneration and tumorigenesis by organoid culture experiments using Stat3∆IEC mouse-derived intestinal epithelial cells in which Stat3 was disrupted. The regeneration of intestinal mucosa and organoid formation were significantly suppressed by Stat3 disruption, which was compensated by Wnt activation. Furthermore, once organoids were recovered, Stat3 was no longer required for organoid growth. These results indicate that Stat3 and Wnt signaling cooperatively protect epithelial cells at the early phase of intestinal regeneration. In contrast, intestinal tumorigenesis was not suppressed by Stat3 disruption in adenomatous polyposis coli ( Apc) Δ716 and Apc∆716 Tgfbr2∆IEC mice, thus indicating that Stat3 is not required for Wnt activation-driven intestinal tumorigenesis. Mechanistically, Itga5 and Itga6 were down-regulated by Stat3 disruption, and focal adhesion kinase (FAK) activation was also suppressed. Notably, FAK inhibitor suppressed the organoid formation of wild-type epithelial cells. These results indicate that Stat3 is indispensable for the survival of epithelial cells through the activation of integrin signaling and the downstream FAK pathway; however, it is not required for the Wnt signaling-activated normal or tumor epithelial cells.-Oshima, H., Kok, S.-Y., Nakayama, M., Murakami, K., Voon, D. C.-C., Kimura, T., Oshima, M. Stat3 is indispensable for damage-induced crypt regeneration but not for Wnt-driven intestinal tumorigenesis

悪性サブクローンによる線維性ニッチ形成を介した遺伝的に多様な細胞集団の転移誘導機構

第19回　高安賞優秀論文賞受賞Nature Communications 12(1): 863, 2021　2021年2月掲

Histological and biochemical characterization of oil palm (Elaeis guineensis jacq.) endosperm during fruit development

Oil palm (Elaeis guineensis) is commercially planted in Malaysia and Indonesia for palm oil production. Palm oil has become the largest source of edible oil in the world. With increasing global demand for vegetable oil coupled with the challenges in production, there is an urgent need to improve palm oil productivity. Therefore, in vitro propagation of oil palm has been in progress to regenerate desirable traits in order to meet the world demand. However, the oil palm tissue culture technique is still inefficient and there is also no universal culture medium for all genotypes. One of the focus areas is the optimization of media formulation for enhanced somatic embryogenesis through the understanding of endosperm development. Thus, the aim of this study was to investigate changes in nutrient composition and morphology of endosperm during fruit development. Histological features of oil palm fruits were examined by histochemistry and light microscopy. Oil palm endosperm formation started at 2 weeks after anthesis (WAA) and it was in liquid form. Enlargement of endosperm occurred as the seed developed further. Cellularization occurred at 8 WAA and cells started grow around periphery of the endocarp. The cells in endosperm continued to grow towards the centre of endosperm. The mature endosperm contained numerous nutrient reserves which was essential for nurturing embryo growth. Biochemical compositions in developing oil palm fruits were analysed by chromatographic and atomic spectroscopic techniques. Glutamic acid was the predominant amino acid followed by aspartic acid and arginine throughout the endosperm developmental stages of both planting materials, tenera and clonal. It was suggested that the glutamic acid, aspartic acids and arginine were the main building block in kernel protein. At early stages of seed development, the high hexose/sucrose ratio in tenera (57.85) and clonal (250.53) was observed which is important to meet the high metabolic demand required for cell division and differentiation. However,the ratio was switched at 10WAA in both tenera and clonal (0.80 and 1.53, respectively) which indicated the onset of endosperm maturation phase. Analysis of fatty acids revealed that lauric acid was the most abundant fatty acid in mature oil palm endosperm of tenera (54%) and clonal (51%). The macro and micro mineral elements are essential for plant growth. High amount of manganese and calcium were found at 5 WAA. Manganese content found in tenera and clonal endosperm was 68 mg/100g dw and 158 mg/100g dw, respectively. While, calcium content found in tenera and clonal endosperm was 797 mg/100g dw and 6350 mg/100g dw, respectively. For both tenera and clonal, potassium (108 and 751 mg/100g dw, respectively) and phosphorus (653 and 695 mg/100g dw respectively) were accumulated in mature endosperm. Analyses of vitamins showed that alpha-tocopherol and niacin were the predominant vitamins found in both oil palm endosperms. On the whole, the anatomical and nutritional study of oil palm endosperm has provided information on cellular changes and nutrient requirements for zygotic embryo development. This knowledge will be useful in optimizing the tissue culture media of oil palm in order to improve the efficiency of somatic embryogenesis

Comparative proteomic analysis of oil palm (Elaeis guineensis Jacq.) during early fruit development

To gain insights on protein changes in fruit setting and growth in oil palm, a comparative proteomic approach was undertaken to study proteome changes during its early development. The variations in the proteome at five early developmental stages were investigated via a gel-based proteomic technique. A total of 129 variant proteins were determined using mass spectrometric analysis, resulting in 80 identifications. The majority of the identified protein species were classified as energy and metabolism, stress response/defence and cell structure during early oil palm development representing potential candidates for the control of final fruit size and composition. Seven prominent protein species were then characterised using real-time polymerase chain reaction to validate the mRNA expression against the protein abundant profiles. Transcript and protein profiles were parallel across the developmental stages, but divergent expression was observed in one protein spot, indicative of possible post-transcriptional events. Our results revealed protein changes in early oil palm fruit development provide valuable information in the understanding of fruit growth and metabolism during early stages that may contribute towards improving agronomic traits