In vitro import of peroxisome-targeting signal type 2 (PTS2) receptor Pex7p into peroxisomes

AbstractPex7p, the peroxisome-targeting signal type 2 (PTS2) receptor, transports PTS2 proteins to peroxisomes from the cytosol. We here established a cell-free Pex7p translocation system. In assays using post-nuclear supernatant fractions each from wild-type CHO-K1 and pex7 ZPG207 cells, 35S-labeled Pex7p was imported into peroxisomes. 35S-Pex7p import was also evident using rat liver peroxisomes. 35S-Pex7p was not imported into peroxisomal remnants from a pex5 ZPG231 defective in PTS2 import and pex2 Z65. When the import of 35S-Pex5pL was inhibited with an excess amount of recombinant Pex5pS, 35S-Pex7p import was concomitantly abrogated, suggesting that Pex5pL was a transporter for Pex7p, unlike a yeast cochaperone, Pex18p. 35S-Pex7p as well as 35S-Pex5p was imported in an ATP-independent manner, whilst the import of PTS1 and PTS2 cargo-proteins was ATP-dependent. Thereby, ATP-independent import of Pex7p implicated that Pex5p export requiring ATP hydrolysis is not a limiting step for its cargo recruitment to peroxisomes. PTS1 protein import was indeed insensitive to N-ethylmaleimide, whereas Pex5p export was N-ethylmaleimide-sensitive. Taken together, the cargo-protein translocation through peroxisomal membrane more likely involves another ATP-requiring step in addition to the Pex5p export. Moreover, upon concurrent import into peroxisomes, 35S-Pex5pL and 35S-Pex7p were detected at mutually distinct ratios in the immunoprecipitates each of the import machinery peroxins including Pex14p, Pex13p, and Pex2p, hence suggesting that Pex7p as well as Pex5p translocated from the initial docking complex to RING complex on peroxisomes

Comet 9P/Tempel 1: Interpretation with the Deep Impact Results

According to our common understandings, the original surface of a short-period comet nucleus has been lost by sublimation processes during its close approaches to the Sun. Sublimation results in the formation of a dust mantle on the retreated surface and in chemical differentiation of ices over tens or hundreds of meters below the mantle. In the course of NASA's Deep Impact mission, optical and infrared imaging observations of the ejecta plume were conducted by several researchers, but their interpretations of the data came as a big surprise: (1) The nucleus of comet 9P/Tempel 1 is free of a dust mantle, but maintains its pristine crust of submicron-sized carbonaceous grains; (2) Primordial materials are accessible already at a depth of several tens of cm with abundant silicate grains of submicrometer sizes. In this study, we demonstrate that a standard model of cometary nuclei explains well available observational data: (1) A dust mantle with a thickness of ~1-2 m builds up on the surface, where compact aggregates larger than tens of micrometers dominate; (2) Large fluffy aggregates are embedded in chemically differentiated layers as well as in the deepest part of the nucleus with primordial materials. We conclude that the Deep Impact results do not need any peculiar view of a comet nucleus.Comment: 11 pages, 1 figure, 1 table. ApJ letters, 673, L199-20

Distribution and Endocrine Morphology of Polypeptide YY (PYY) Containing Cells in the Human Gut

Using human materials, the distribution of PYY containing cells was determined by immunocytochemical methods and discussion was made on their morphological endocrinology. PYY cells were fairly numerous in the lower gastrointestinal tract of man, particularly in the colon and rectum. The cells were also present in the pancreas and duodenum but quite rarely. PYY cells were not observed at all in the lower part of the esophagus, stomach and gall bladder. Their peculiar and characteristic shapes as well as distribution suggest that PYY may have some action (probably specific) on the function of the distal gastrointestinal tract

Spontaneous Remission of Solitary-Type Infantile Myofibromatosis

Infantile myofibromatosis is a rare fibrous tumor of infancy. The cutaneous solitary type has typically an excellent prognosis. However, histologically, it is important to rule out leiomyosarcoma, which has a poor prognosis. The low frequency of mitosis was definitive for a diagnosis of infantile myofibromatosis. We present a cutaneous solitary-type case of infantile myofibromatosis. Following incisional biopsy, the tumor remitted spontaneously

Ectopic adrenal adenoma causing gross hematuria: Steroidogenic enzyme profiling and literature review

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/149375/1/iju512068.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/149375/2/iju512068_am.pd

Early Diagnosis of Wolfram Syndrome by Ophthalmologic Screening in a Patient with Type 1B Diabetes Mellitus: A Case Report

Wolfram syndrome (WS) is a monogenic diabetes caused by variants of the WFS1 gene. It is characterized by diabetes mellitus (DM) and optic atrophy. Individuals with WS initially present with autoantibody-negative type 1 DM (type 1B DM; T1BDM). The diagnosis is often delayed or misdiagnosed, even after visual impairment becomes apparent. We report a case of WS diagnosed by ophthalmologic screening before the appearance of visual impairment. A 7-year-old male patient developed T1BDM at the age of 3 years. At 6 years of age, his endogenous insulin secretion decreased but was not completely absent, and glycemic control was good with insulin treatment. Fundus examination at that time revealed optic nerve head pallor, and WFS1 gene analysis confirmed a compound heterozygous variant (c.2483delinsGGA/c.1247T>A). Ophthalmological screening can help in early diagnosis of WS in T1BDM, especially when endogenous insulin secretion is preserved, which would facilitate effective treatment

Effectiveness of metformin and lifestyle interventions as an initial treatment in Japanese patients with newly diagnosed type 2 diabetes : a prospective observational study

Although global guidelines recommend metformin and lifestyle interventions as an initial treatment in patients with newly diagnosed type 2 diabetes (T2DM), few reports exist about its effectiveness in Japanese patients. To examine its effectiveness, we performed a prospective observational study within a routine clinical setting. We provided metformin (≥1,500 mg/day) and lifestyle interventions to 23 patients with newly diagnosed T2DM (20 men and 3 women, mean age 53 years, mean body mass index [BMI] 25.7 kg/m2). After 16 weeks, HbA1c levels significantly decreased from 9.1±2.1% (mean±SD) to 6.6±0.8% (p<0.001). Thirteen patients (56.5%) achieved a target HbA1c<6.5%. We did not find a significant correlation between baseline BMI and the changes in HbA1c (ΔHbA1c) (r=-0.165, p=0.451). In contrast, we found a significant correlation between baseline fasting plasma glucose and ΔHbA1c (r=-0.755, p<0.001). Body weight decreased from 73.3±13.3 kg to 69.8±11.6 kg (p<0.001). Total cholesterol, low density lipoprotein-cholesterol, non-high density lipoprotein-cholesterol, and serum vitamin B-12 concentrations also significantly decreased. Adverse events included diarrhea (26.1%) and mild elevation of liver enzymes (8.7%). These results suggest that metformin and lifestyle interventions is effective and safe as an initial treatment in Japanese patients with newly diagnosed T2DM

Task Attention Facilitates Learning of Task-Irrelevant Stimuli

Attention plays a fundamental role in visual learning and memory. One highly established principle of visual attention is that the harder a central task is, the more attentional resources are used to perform the task and the smaller amount of attention is allocated to peripheral processing because of limited attention capacity. Here we show that this principle holds true in a dual-task setting but not in a paradigm of task-irrelevant perceptual learning. In Experiment 1, eight participants were asked to identify either bright or dim number targets at the screen center and to remember concurrently presented scene backgrounds. Their recognition performances for scenes paired with dim/hard targets were worse than those for scenes paired with bright/easy targets. In Experiment 2, eight participants were asked to identify either bright or dim letter targets at the screen center while a task-irrelevant coherent motion was concurrently presented in the background. After five days of training on letter identification, participants improved their motion sensitivity to the direction paired with hard/dim targets improved but not to the direction paired with easy/bright targets. Taken together, these results suggest that task-irrelevant stimuli are not subject to the attentional control mechanisms that task-relevant stimuli abide