23 research outputs found
Rare presentation of an atrial myxoma in an adolescent patient: A case report and literature review
BACKGROUND: Cardiac tumors are uncommon in the pediatric population. When present, cardiac manifestations stem from the tumor causing inflow or outflow obstruction. While common in adults, cardiac myxomas presenting with generalized systemic illness or peripheral emboli especially with no cardiac or neurological symptoms are rare in children.
CASE PRESENTATION: We report a case of a previously healthy adolescent girl who presented with a 6-month history of constitutional symptoms and a purpuric rash with no cardiac or neurologic symptoms, found to have a cardiac myxoma.
CONCLUSIONS: A vasculopathic rash in the setting of atrial myxomas has been shown be a precursor to significant morbidity and mortality. Due to the rarity of this entity, the time elapsed from onset of non-cardiac symptoms until diagnosis of a myxoma is usually prolonged with interval development of irreversible neurological sequelae and death reported in the literature. Therefore, we highlight the importance of including cardiac myxomas and paraneoplastic vasculitis early in the differential diagnosis for patients presenting with a purpuric rash and systemic symptoms
Conditional loss of PTEN leads to testicular teratoma and enhances embryonic germ cell production
Influence of petrographic textures on the shapes of impact experiment fine fragments measuring several tens of microns: Comparison with Itokawa regolith particles
In 2010, fine regolith particles on asteroid Itokawa were recovered by the Hayabusa mission. The three-dimensional microstructure of 48 Itokawa particles smaller than 120 µm was examined in previous studies. The shape distribution of Itokawa particles is distributed around the mean values of the axial ratio 2:√2:1, which is similar to laboratory impact fragments larger than several mm created in catastrophic disruptions. Thus, the Itokawa particles are considered to be impact fragments on the asteroid's surface. However, there have never been any laboratory impact experiments investigating the shapes of fine fragments smaller than 120 µm, and little is known about the relation between the shapes of fine fragments and the petrographic textures within those fragments. In this study, in order to investigate the relation between the petrographic textures and the shapes of fine fragments by impacts, the shapes of 2163 fine fragments smaller than 120 µm are examined by synchrotron radiation-based microtomography at SPring-8. Most samples are fine fragments from basalt targets, obtained in previous laboratory impact experiments by Michikami et al. (2016). Moreover, two impacts into L5 chondrite targets were carried out and the shapes of their fine fragments are examined for comparison. The results show that the shape distributions of fine fragments in basalt targets are similar regardless of impact energy per target mass (in contract to the shape distribution of relatively large fragments, which are affected by impact energy), and are similar to those in L5 chondrite targets and Itokawa regolith particles. The physical process producing these fine fragments would be due to multiple rarefaction waves in the target. Besides, the petrographic textures do not significantly affect the shapes of fine fragments in our experiments. On the other hand, according to Molaro et al. (2015), the shapes of the fragments produced by thermal fatigue by the day-night temperature cycles on the asteroid surface are influenced by the petrographic textures. Therefore, we conclude that the Itokawa particles are not the products of thermal fatigue but impact fragments on the asteroid surface
阪神パークのチンパンジー
“Hanshin Park” located in Nishinomiya, Hyogo prefecture was an amusement park owned and operated by the Hanshin electric railway company limited. The park was opened near Koshien Stadium in 1929, using the land after the exposition of accession for Emperor Showa. In the1930’s it had a chimpanzee, extremely unusual to see for the public in Japan. Unfortunately, the park was closed in 2003. We investigated the history of the facility the chimpanzees lived in, by checking documents, newspaper articles, and research papers. The female chimpanzee named“ Opera” was imported to Japan from Africa in 1934 and she became nationally famous, riding a bicycle, walking on stilts, and so on. Although it is not known when Opera died, it is estimated that she lived there for 2 to 5 years. A male chimpanzee named“ Bamboo” came to Kobe around 1940. Because the site of the park was using for military airport, he had to move to Higashiyama Zoo, Nagoya-city in 1943. By the end of World War II, he was the only chimpanzee still alive in Japan. Hanshin Park was opened again nearby in 1950 and a female chimpanzee named“ Birdie” arrived in 1973. Two of the three chimpanzees found in this research were not registered in the Japanese Association of Zoos and Aquariums studbook. The information will be valuable not only for learning more about captive chimpanzees but also for improvement of their welfare
The aryl hydrocarbon receptor instructs the immunomodulatory profile of a subset of Clec4a4 eosinophils unique to the small intestine
C-type lectin domain family 4, member a4 (Clec4a4) is a C-type lectin inhibitory receptor specific for glycans thought to be exclusively expressed on murine CD8α− conventional dendritic cells. Using newly generated Clec4a4-mCherry knock-in mice, we identify a subset of Clec4a4-expressing eosinophils uniquely localized in the small intestine lamina propria. Clec4a4+ eosinophils evinced an immunomodulatory signature, whereas Clec4a4− eosinophils manifested a proinflammatory profile. Clec4a4+ eosinophils expressed high levels of aryl hydrocarbon receptor (Ahr), which drove the expression of Clec4a4 as well as other immunomodulatory features, such as PD-L1. The abundance of Clec4a4+ eosinophils was dependent on dietary AHR ligands, increased with aging, and declined in inflammatory conditions. Mice lacking AHR in eosinophils expanded innate lymphoid cells of type 2 and cleared Nippostrongylus brasiliensis infection more effectively than did wild-type mice. These results highlight the heterogeneity of eosinophils in response to tissue cues and identify a unique AHR-dependent subset of eosinophils in the small intestine with an immunomodulatory profile
An fMRI Investigation into the Effects of Ketogenic Medium-Chain Triglycerides on Cognitive Function in Elderly Adults: A Pilot Study
Evidence suggests that oral intake of medium-chain triglycerides (MCTs), which promote the production of ketone bodies, may improve cognitive functions in elderly people; however, the underlying brain mechanisms remain elusive. We tested the hypothesis that cognitive improvement accompanies physiological changes in the brain and reflects the use of ketone bodies as an extra energy source. To this end, by using functional magnetic resonance imaging, cerebral blood oxygenation level-dependent (BOLD) signals were measured while 20 healthy elderly subjects (14 females and 6 males; mean age: 65.7 ± 3.9 years) were engaged in executive function tasks (N-back and Go-Nogo) after ingesting a single MCT meal (Ketonformula®) or placebo meal in a randomized, double-blind placebo-controlled design (UMIN000031539). Morphological characteristics of the brain were also examined in relation to the effects of an MCT meal. The MCT meal improved N-back task performance, and this was prominent in subjects who had reduced grey matter volume in the dorsolateral prefrontal cortex (DLPFC), a region known to promote executive functions. When the participants were dichotomized into high/low level groups of global cognitive function at baseline, the high group showed improved N-back task performance, while the low group showed improved Go-Nogo task performance. This was accompanied by decreased BOLD signals in the DLPFC, indicative of the consumption of ketone bodies as an extra energy source
A type I DnaJ homolog, DjA1, regulates androgen receptor signaling and spermatogenesis
Two type I DnaJ homologs DjA1 (DNAJA1; dj2, HSDJ/hdj-2, rdj1) and DjA2 (DNAJA2; dj3, rdj2) work similarly as a cochaperone of Hsp70s in protein folding and mitochondrial protein import in vitro. To study the in vivo role of DjA1, we generated DjA1-mutant mice. Surprisingly, loss of DjA1 in mice led to severe defects in spermatogenesis that involve aberrant androgen signaling. Transplantation experiments with green fluorescent protein-labeled spermatogonia into DjA1(−/−) mice revealed a primary defect of Sertoli cells in maintaining spermiogenesis at steps 8 and 9. In Sertoli cells of DjA1(−/−) mice, the androgen receptor markedly accumulated with enhanced transcription of several androgen-responsive genes, including Pem and testin. Disruption of Sertoli–germ cell adherens junctions was also evident in DjA1(−/−) mice. Experiments with DjA1(−/−) fibroblasts and primary Sertoli cells indicated aberrant androgen receptor signaling. These results revealed a critical role of DjA1 in spermiogenesis and suggest that DjA1 and DjA2 are not functionally equivalent in vivo