Tissue-specific laminin expression facilitates integrin-dependent association of the embryonic wing disc with the trachea in Drosophila

AbstractThe interaction of heterologous tissues involves cell adhesion mediated by the extracellular matrix and its receptor integrins. The Drosophila wing disc is an ectodermal invagination that contacts specific tracheal branches at the basolateral cell surface. We show that an α subunit of laminin, encoded by wing blister (wb), is essential for the establishment of the interaction between the wing and trachea. During embryogenesis, wing disc cells present Wb at their basolateral surface and extend posteriorly, expanding their association to more posteriorly located tracheal branches. These migratory processes are impaired in the absence of the trachea, Wb, or integrins. Time-lapse and transmission electron microscopy analyses suggest that Wb facilitates integrin-dependent contact over a large surface and controls the cellular behavior of the wing cells, including their exploratory filopodial activity. Our data identify Wb laminin as an extracellular matrix ligand that is essential for integrin-dependent cellular migration in Drosophila

Theoretical properties of Bayesian Student-tt linear regression

Student-$t$ linear regression is a commonly used alternative to the normal model in Bayesian analysis when one wants to gain robustness against outliers. The assumption of heavy-tailed error distribution makes the model more adapted to a potential presence of outliers by assigning higher probabilities to extreme values. Even though the Student-$t$ model is often used in practice, not a lot is known about its theoretical properties. In this paper, we aim to fill some gaps by providing analyses in two different asymptotic scenarios. In the first one, outliers are considered to be further and further away from the bulk of the data. The analysis allows to characterize the limiting posterior distribution, a distribution in which a trace of the outliers is present, making the approach partially robust. The impact of the trace is seen to increase with the degrees of freedom of the Student-$t$ distribution assumed. The second asymptotic scenario is one where the sample size increases and the normal model is the true generating process to be able to compare the efficiency of the robust estimator to the ordinary-least-squares one when the latter is the benchmark. The asymptotic efficiency is comparable, in the sense that the variance of the robust estimator is inflated but only by a factor, and this factor converges to 1 as the degrees of freedom increase. The trade-off between robustness and efficiency controlled through the degrees of freedom is thus precisely characterized (at least asymptotically)

因果関係モデルによる腎移植レシピエントのQOLの分析

The purpose of this study is to analyze the structural relationship among the components of quality of life of kidney transplant recipients by using a causal model. The subjects were 329 recipients who had regular checks-up following transplantation in seven general hospitals in Tokyo, Gunma, Aichi, Okayama, and Hiroshima, and agreed to participate in this study. Ferrans and Powers's Quality of Life - Index Kidney Transplant version was used to measure perceived quality of life. The self-administered questionnaires were handed over to the subjects, who completed the instrument on the spot. After that, the answers were collected immediately. The factor analysis and the covariance structure analysis were used to make clear the structural relationship among the components of quality of life. The results of data analysis were as follows : (1) Five components of quality of life were extracted ; socio-economic functioning, family ties, emotional support, physical health, and peace & happiness. (2) The scores in the family ties dimension and the physical health dimension were higher than in the others, and the score in the socio-economic functioning dimension was the lowest. (3) The physical health showed the starting point in a causal model. (4) The physical health influenced the family ties and the socio-economic functioning. (5) The socio-economic functioning strongly influenced the peace & happiness and the emotional support. (6) The family ties influenced the socio-economic functioning, the emotional support, and the peace & happiness. Therefore, it was conceivable that it was particularly important to make approaches for the physical health, the family ties, and the socio-economic functioning dimensions to improve quality of life.本研究は，因果関係モデルによって，腎移植後レシピエントのQOLの構成要素間の関係を明らかにすることを目的としている。対象者は，東京，群馬，愛知，岡山，広島の7医療機関に外来通院中で，研究に同意が得られた329名の腎移植後のレシピエントである。レシピエントのQOLに関するデータは，Ferrans＆PowersのQuality of Life Index―Kidney Transplant versionの測定用具を用いて収集した。収集は外来受診時に行い，対象者に自己記入式質問紙を配布し，その場で記入してもらった後，直ちに回収した。データ分析は，QOLの構成要素と構成要素間の因果関係を明らかにするために，因子分析と共分散構造分析を行った。分析結果は以下の通りである。すなわち、(1)QOLの構成要素として，社会・経済的な機能，家族の絆，情緒的な支え，身体の健康，安らぎと幸福の5つが抽出された。(2)「家族の絆」と「身体の健康」についての得点が高く，「社会・経済的な機能」についての得点が最も低かった。(3)因果関係モデルにおいて，「身体的な健康」が原点となっていた。(4)「身体的な健康」は，「家族の絆」と「社会・経済的な機能」に影響を及ぼしていた。(5)「社会・経済的な機能」は，「安らぎと幸福」と「情緒的な支え」に強く影響を及ぼしていた。(6)「家族の絆」は，「社会・経済的な機能」，「情緒的な支え」，「安らぎと幸福」に影響を及ぼしていた。したがって、レシピエントのQOLを高めるために，「身体的な健康」，「家族の絆」，「社会・経済的な機能」の側面に働きかけていくことが特に重要であると考えられた

Development of 1,3a,6a-triazapentalene-labeled enterobactin as a fluorescence quenching sensor of iron ion

1,3a,6a-Triazapentalene (TAP)-labeled enterobactin was developed as an iron ion sensor. 3-Acetylated-TAP was successfully introduced to the catechol ring of enterobactin, a well-recognized siderophore secreted by various Gram-negative bacteria. The fluorescence of TAPlabeled enterobactin decreased gradually as the amount of Fe3+ ion as an additive was increased, and 1.2 equiv of Fe3+ ion completely quenched the fluorescence. In clear contrast, when other metal ions were used, the fluorescence of TAP-labeled enterobactin remained even at 5.0 equiv

GATA2 functions in adrenal chromaffin cells

Catecholamine synthesized in the sympathoadrenal system, including sympathetic neurons and adrenal chromaffin cells, is vital for cardiovascular homeostasis. It has been reported that GATA2, a zinc finger transcription factor, is expressed in murine sympathoadrenal progenitor cells. However, a physiological role for GATA2 in adrenal chromaffin cells has not been established. In this study, we demonstrate that GATA2 is specifically expressed in adrenal chromaffin cells. We examined the consequences of Gata2 loss- of- function mutations, exploiting a Gata2 conditional knockout allele crossed to neural crest- specific Wnt1- Cre transgenic mice (Gata2 NC- CKO). The vast majority of Gata2 NC- CKO embryos died by embryonic day 14.5 (e14.5) and exhibited a decrease in catecholamine- producing adrenal chromaffin cells, implying that a potential catecholamine defect might lead to the observed embryonic lethality. When intercrossed pregnant dams were fed with synthetic adrenaline analogs, the lethality of the Gata2 NC- CKO embryos was partially rescued, indicating that placental transfer of the adrenaline analogs complements the lethal catecholamine deficiency in the Gata2 NC- CKO embryos. These results demonstrate that GATA2 participates in the development of neuroendocrine adrenaline biosynthesis, which is essential for fetal survival.GATA2 is specifically expressed in adrenal chromaffin cells in which GATA2 plays a role for catecholamine biosynthesis.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/162786/2/gtc12795_am.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/162786/1/gtc12795.pd

Late Established Mutans Streptococci in Children over 3 Years Old

Acquisition of mutans streptococci has been reported to most commonly occur at approximately 26 months of age. In the present study, we detected Streptococcus mutans and S. sobrinus using polymerase chain reaction (PCR) assays in children, then re-examined the subjects to determine the time of acquisition of these bacteria over a 1-year period. The subjects were 57 children ranging in age from 3 to 5 years old, each with primary dentition. Plaque samples were collected from all erupted tooth sites using a sterile toothbrush. PCR assays were performed to detect the targeted mutans streptococci at the beginning of the study (baseline) and after 1 year. At the baseline examination, the prevalence of S. mutans and S. sobrinus was 61.4% and 54.4%, respectively, in all subjects, of whom 14 (24.6%) were positive for S. mutans alone, 10 (17.5%) for S. sobrinus alone, and 21 (36.8%) for both S. mutans and S. sobrinus, with 12 (21.1%) negative for both. After 1 year, 4 of 22 (18.2%) subjects newly had acquired S. mutans and 15 of 26 (57.7%) had aquired S. sobrinus, while 5 (8.8%) remained negative for both bacteria. The age of the first positive S. mutans finding ranged from 49 to 71 months, while that for S. sobrinus ranged from 49 to 81 months old. Our results suggest that S. sobrinus becomes established later than S. mutans in the oral cavities of children over the age of 3 years old

Lemon Polyphenols Suppress Diet-induced Obesity by Up-Regulation of mRNA Levels of the Enzymes Involved in β-Oxidation in Mouse White Adipose Tissue

The aim of this study was to investigate the effect of dietary lemon polyphenols on high-fat diet-induced obesity in mice, and on the regulation of the expression of the genes involved in lipid metabolism to elucidate the mechanisms. Mice were divided into three groups and fed either a low fat diet (LF) or a high fat diet (HF) or a high fat diet supplemented with 0.5% w/w lemon polyphenols (LP) extracted from lemon peel for 12 weeks. Body weight gain, fat pad accumulation, the development of hyperlipidemia, hyperglycemia, and insulin resistance were significantly suppressed by lemon polyphenols. Supplementation with lemon polyphenols also significantly up-regulated the mRNA level of the peroxisome proliferator activated receptor-α (PPARα) compared to the LF and HF groups in the liver. Furthermore, the mRNA level of acyl-CoA oxidase (ACO) was up-regulated in the LP group compared to the LF group, but not HF group in the liver, and was also significantly increased in the epididymal white adipose tissue. Thus, feeding with lemon polyphenols suppressed body weight gain and body fat accumulation by increasing peroxisomal β-oxidation through up-regulation of the mRNA level of ACO in the liver and white adipose tissue, which was likely mediated via up-regulation of the mRNA levels of PPARα