A long-term eutrophication process observed from the changes in the horizontal distribution of profundal oligochaete fauna in mesotrophic-eutrophic Lake Kawaguchi, Japan

The purpose of this study was to record the oligochaete fauna in Lake Kawaguchi and clarify their horizontal distribution. In addition, annual changes in the lake were recorded. Samples were collected between 5 March 1993 and 7 March 2006 by using a standard Ekman-Birge sampler at 22 stations, and multipoint sampling surveys were carried out. As a result of the study, a total of 8 species belonging to 6 genera and 3 subfamilies were identified. The average density of oligochaetes for the entire lake was 5247 +/- 3873 ind m(-2) and the average wet weight of oligochaetes was 25.5 +/- 23.4 g m(-2) in 1993, compared to 1075 +/- 676 ind m(-2) and 2.7 +/- 1.7 g m(-2), respectively, in 2006. Tubifex tubifex had inhabited the entire lake bottom in 1993, but Limnodrilus spp. inhabited only the center of the lake in 2006. In recent years, the total number of oligochaetes has shown a tendency to increase, compared with the past record from the 1970s, suggesting that eutrophication is an ongoing process.ArticleTURKISH JOURNAL OF ZOOLOGY. 36(1):39-46 (2012)journal articl

Synthesis and Characterization of Anti-HER2 Antibody Conjugated CdSe/CdZnS Quantum Dots for Fluorescence Imaging of Breast Cancer Cells

The early detection of HER2 (human epidermal growth factor receptor 2) status in breast cancer patients is very important for the effective implementation of anti-HER2 antibody therapy. Recently, HER2 detections using antibody conjugated quantum dots (QDs) have attracted much attention. QDs are a new class of fluorescent materials that have superior properties such as high brightness, high resistance to photo-bleaching, and multi-colored emission by a single-light source excitation. In this study, we synthesized three types of anti-HER2 antibody conjugated QDs (HER2Ab-QDs) using different coupling agents (EDC/sulfo-NHS, iminothiolane/sulfo-SMCC, and sulfo-SMCC). As water-soluble QDs for the conjugation of antibody, we used glutathione coated CdSe/CdZnS QDs (GSH-QDs) with fluorescence quantum yields of 0.23∼0.39 in aqueous solution. Dispersibility, hydrodynamic size, and apparent molecular weights of the GSH-QDs and HER2Ab-QDs were characterized by using dynamic light scattering, fluorescence correlation spectroscopy, atomic force microscope, and size-exclusion HPLC. Fluorescence imaging of HER2 overexpressing cells (KPL-4 human breast cancer cell line) was performed by using HER2Ab-QDs as fluorescent probes. We found that the HER2Ab-QD prepared by using SMCC coupling with partially reduced antibody is a most effective probe for the detection of HER2 expression in KPL-4 cells. We have also studied the size dependency of HER2Ab-QDs (with green, orange, and red emission) on the fluorescence image of KPL-4 cells

Grafting of iPS cell-derived tenocytes promotes motor function recovery after Achilles tendon rupture

ヒトのiPS細胞から腱の細胞を作製する --アキレス腱断裂のラットに移植し、機能回復を確認--. 京都大学プレスリリース. 2021-08-31.Repairing tendon injuries with stem cells. 京都大学プレスリリース. 2021-08-31.Tendon self-renewal is a rare occurrence because of the poor vascularization of this tissue; therefore, reconstructive surgery using autologous tendon is often performed in severe injury cases. However, the post-surgery re-injury rate is relatively high, and the collection of autologous tendons leads to muscle weakness, resulting in prolonged rehabilitation. Here, we introduce an induced pluripotent stem cell (iPSC)-based technology to develop a therapeutic option for tendon injury. First, we derived tenocytes from human iPSCs by recapitulating the normal progression of step-wise narrowing fate decisions in vertebrate embryos. We used single-cell RNA sequencing to analyze the developmental trajectory of iPSC-derived tenocytes. We demonstrated that iPSC-tenocyte grafting contributed to motor function recovery after Achilles tendon injury in rats via engraftment and paracrine effects. The biomechanical strength of regenerated tendons was comparable to that of healthy tendons. We suggest that iPSC-tenocytes will provide a therapeutic option for tendon injury

Glycine insertion makes yellow fluorescent protein sensitive to hydrostatic pressure

Fluorescent protein-based indicators for intracellular environment conditions such as pH and ion concentrations are commonly used to study the status and dynamics of living cells. Despite being an important factor in many biological processes, the development of an indicator for the physicochemical state of water, such as pressure, viscosity and temperature, however, has been neglected. We here found a novel mutation that dramatically enhances the pressure dependency of the yellow fluorescent protein (YFP) by inserting several glycines into it. The crystal structure of the mutant showed that the tyrosine near the chromophore flipped toward the outside of the β-can structure, resulting in the entry of a few water molecules near the chromophore. In response to changes in hydrostatic pressure, a spectrum shift and an intensity change of the fluorescence were observed. By measuring the fluorescence of the YFP mutant, we succeeded in measuring the intracellular pressure change in living cell. This study shows a new strategy of design to engineer fluorescent protein indicators to sense hydrostatic pressure

Tornar-se professor: desvelando a atuação docente no início do exercício da docência

This research, based on authors such as Was (1999), Guarnieri (1996 and 2005), Freitas (2002 and 2007) argue that the understanding of teacher education as a complex continuum aimed at understanding the initiation of the educational performance in the first five years of professional practice, by analyzing the history of teaching teachers early in their career. As we contemplate the specific objectives of interest to examine the training received to enter and work in the classroom and the experiences in teaching at undergraduate students. To perform the empirical study we adopted the use of semi-structured, guided by an outline of issues significant to the conduct of the respondents' narratives. The main results can highlight the difficulties encountered at the beginning of the educational performance are recurrent, data analysis shows that there is a significant increase in the duties of the teacher. With the study arrives at the premise that we must rethink the quality and structure of training courses aimed at improving the quality of performance of professional education, but for this to occur there must be deepening of studies and improvements not only in initial training and in continuing education courses. It is understood here that the training is not solely responsible for the current educational scene, which encompasses the question of the beginner there are many issues to be studied, such as public policies, structuring the curriculum, pay, but the training is beginning to there are faculty prepared to actA presente pesquisa, baseada em autores como Esteve (1999), Guarnieri (1996 e 2005), Freitas (2002 e 2007) que defendem a compreensão da formação de professores como um complexo contínuo tem como objetivo compreender o início da atuação docente nos primeiros cinco anos de exercício profissional, por meio da análise da história da docência de professores no início da carreira. Como objetivos específicos contemplamos o interesse em analisar a formação recebida para ingressar e atuar na sala de aula e as vivências no magistério pelo ingressante. Para a realização do estudo empírico adotamos o uso da entrevista semi-estruturada, guiada por um roteiro de temáticas significativas para a condução da narrativa dos entrevistados. Dentre os principais resultados podemos destacar que as dificuldades encontradas no início da atuação docente são recorrentes, a análise dos dados mostra que há um aumento significativo das funções do professor. Com o estudo realizado chega-se a premissa de que é preciso repensar a qualidade e a estrutura dos cursos de formação, visando melhorar a qualidade do desempenho do profissional da educação, mas para que isto ocorra é necessário que haja “aprofundamento” de estudos e melhorias não só na formação inicial bem como nos cursos de formação continuada. Entende-se neste trabalho que a formação não é a única responsável pelo atual cenário educacional, que engloba a questão do iniciante, há inúmeras questões a serem estudadas, como políticas públicas, estruturação do currículo, condições salariais, mas a formação é o inicio para que haja corpo docente preparado para atua

Enhanced Bonding Strength of Hydrophobically Modified Gelatin Films on Wet Blood Vessels

The bonding behavior between hydrophobically modified alkaline-treated gelatin (hm-AlGltn) films and porcine blood vessels was evaluated under wet conditions. Hexanoyl (Hx: C6), decanoyl (Dec: C10), and stearyl (Ste: C18) chlorides were introduced into the amino groups of AlGltn to obtain HxAlGltn, DecAlGltn, and SteAlGltn, respectively, with various modification percentages. The hm-AlGltn was fabricated into films and thermally crosslinked to obtain water-insoluble films (t-hm-AlGltn). The 42% modified t-HxAlGltn (t-42HxAlGltn) possessed higher wettability than the 38% modified t-DecAlGltn (t-38DecAlGltn) and the 44% modified t-SteAlGltn (t-44SteAlGltn) films, and the t-42HxAlGltn film showed a high bonding strength with the blood vessel compared with all the hm-AlGltn films. Histological observations indicated that t-42HxAlGltn and t-38DecAlGltn remained on the blood vessel even after the bonding strength measurements. From cell culture experiments, the t-42HxAlGltn films showed significant cell adhesion compared to other films. These findings indicate that the Hx group easily interpenetrated the surface of blood vessels and effectively enhanced the bonding strength between the films and the tissue