Morphogenesis of the Spleen During the Human Embryonic Period

We aimed to observe morphological changes in the spleen from the emergence of the primordium to the end of the embryonic period using histological serial sections of 228 samples. Between Carnegie stages (CSs) 14 and 17, the spleen was usually recognized as a bulge in the dorsal mesogastrium (DM), and after CS 20, the spleen became apparent. Intrasplenic folds were observed later. A high-density area was first recognized in 6 of the 58 cases at CS 16 and in all cases examined after CS 18. The spleen was recognized neither as a bulge nor as a high-density area at CS 13. The mesothelium was pseudostratified until CS 16 and was replaced with high columnar cells and then with low columnar cells. The basement membrane was obvious after CS 17. The mesenchymal cells differentiated from cells in the DM, and sinus formation started at CS 20. Hematopoietic cells were detected after CS 18. The vessels were observed at CS 14 in the DM. Hilus formation was observed after CS 20. The parallel entries of the arteries and veins were observed at CS 23. The rate of increase in spleen length in relation to that of stomach length along the cranial-caudal direction was 0.51±0.11, which remained constant during CSs 19 and 23, indicating that their growths were similar. These data may help to better understand the development of normal human embryos and to detect abnormal embryos in the early stages of development

A generalized linear model for decomposing cis-regulatory, parent-of-origin, and maternal effects on allele-specific gene expression

Joint quantification of genetic and epigenetic effects on gene expression is important for understanding the establishment of complex gene regulation systems in living organisms. In particular, genomic imprinting and maternal effects play important roles in the developmental process of mammals and flowering plants. However, the influence of these effects on gene expression are difficult to quantify because they act simultaneously with cis-regulatory mutations. Here we propose a simple method to decompose cis-regulatory (i.e., allelic genotype, AG), genomic imprinting (i.e., parent-of-origin, PO), and maternal (i.e., maternal genotype, MG) effects on allele-specific gene expression using RNA-seq data obtained from reciprocal crosses. We evaluated the efficiency of method using a simulated dataset and applied the method to whole-body Drosophila and mouse trophoblast stem cell (TSC) and liver RNA-seq data. Consistent with previous studies, we found little evidence of PO and MG effects in adult Drosophila samples. In contrast, we identified dozens and hundreds of mouse genes with significant PO and MG effects, respectively. Interestingly, a similar number of genes with significant PO effect were detect in mouse TSCs and livers, whereas more genes with significant MG effect were observed in livers. Further application of this method will clarify how these three effects influence gene expression levels in different tissues and developmental stages, and provide novel insight into the evolution of gene expression regulation.Comment: 27 pages, 3 figures, 2 tabl

Modified Method of Kluver-Barrera's Staining with Microwave Irradiation

クリューバー･バレラ(KB)染色は中枢神経系の白質における重要成分である髄鞘を選択的に染色する方法として日常的に広く使われている｡しかし現在の所,ルクソール･ファスト青(LFB)染色後の0.05%炭酸リチウム及び70%アルコールによる分別時間が確定されていないので,分別の良否を経験的にしか判断せざるをえないという欠点がある｡そこで,本研究において,マイクロウェーブ照射をLFB染色に応用することで,その後の分別について検討した結果,従来の0.05%炭酸リチウムでは良好な結果が得られなかったが分別液として,0.05%炭酸水素ナトリウムおよび70%アルコールを用いることで分別時間の確定が可能となった。Kluver-Barrera's (KB) staining is the well-known and widely used method for staining the Schwann's sheath of the central nervous systems. On the contrary, the optimum time is not established yet, which incubated with 0.05% lithium carbonate and 70% alcohol after luxol fast blue staining. The modified method was studied that was stained with the microwave irradiation and used 0.05% sodium bicarbonate in stead of 0.05% lithium carbonate. This method was simple and useful to differentiate Schwann's sheath from other components

Embryonic dermal condensation and adult dermal papilla induce hair follicles in adult glabrous epidermis through different mechanisms

Hair induction in the adult glabrous epidermis by the embryonic dermis was compared with that by the adult dermis. Recombinant skin, composed of the adult sole epidermis and the embryonic dermis containing dermal condensations (DC), was transplanted onto the back of nude mice. The epidermis of transplants formed hairs. Histology on the induction process demonstrated the formation of placode-like tissues, indicating that the transplant produces hair follicles through a mechanism similar to that underlying hair follicle development in the embryonic skin. An isolated adult rat sole skin piece, inserted with either an aggregate of cultured dermal papilla (DP) cells or an intact DP between its epidermis and dermis, was similarly transplanted. The transplant produced hair follicles. Histology showed that the epidermis in both cases surrounded the aggregates of DP cells. The epidermis never formed placode-like tissues. Thus, it was concluded that the adult epidermal cells recapitulate the embryonic process of hair follicle development when exposed to DC, whereas they get directly into the anagen of the hair cycle when exposed to DP. The expression pattern of Edar and Shh genes, and P-cadherin protein during the hair follicle development in the two types of transplants supported the above conclusion

Atomic Bomb Fallout and “Black rain” at Manose District (Hirama-cho) Located Northeast of Nagasaki City

Plutonium atomic bomb (A-bomb) was exploded at 503 meters height above Nagasaki City on August 9, 1945. Many studies on radioactive contamination, radiation dose, effect to people and so on have been conducted until now. Local fallout from the A-bomb mainly spread a lot in the east direction centering on Nishiyama area located about 4 km east of the hypocenter. Like the Hiroshima A-bomb, black rain accompanied by radioactive materials fell shortly after the explosion, but relationship between local fallout fall zone and black rain fall area has not been sufficiently elucidated, which has enhanced the concerns on radiation exposure to the A-bomb survivor. Concerning the black rain due to the Nagasaki A-bomb, it has been said that black rain did not fall across a wide area in a comprehensive way, except for the heavily contaminated Nishiyama area, but fell at various areas with conditions of light rain and/or soaking after the explosion. Among many villages or towns, especially in the Manose District where is a small intermountain village about 7.5 km northeast of the hypocenter, it had always been heard and known that the residents living there encountered black rain and experienced hair loss. In this district, the hair loss of inhabitants occurred actually with high probability, but its reason has not been elucidated well. Therefore, in order to reevaluate the local fallout level in the Manose District by the A-bomb, residual long-lived radionuclides 137Cs and Pu isotopes were measured for soil samples collected at the Manose District including the surrounding areas in July, 2011. As a result, accumulated levels of 137Cs and 239,240Pu in the Manose District were not so high, each being nearly background (BG) level. The dispersion of local fallout Pu from the A-bomb was reconfirmed by 240Pu/239Pu atomic ratios measured in soil samples at the same time, and was found to be primarily limited in the east direction, especially around the Nishiyama area. Those results were consistent with results obtained so far. Further researches are needed for understanding scientifically the cause of the high incidence rate of hair loss in this district.This research was supported by JSPS KAKENHI Grants Numbers 23406002 (April 2011-March 2014) and 26257501 (April 2014-March 2018)

DETERMINAÇÃO DO TEOR DE ÁGUA DE PIPER NIGRUM L. CULTIVADO NA AMAZÔNIA ORIENTAL

Black pepper is an important agricultural crop in Brazil and other developing countries. Proper drying of pepper is crucial to ensure the quality and safety of the product. The objective of the experiment was to define the water content in the grain of black pepper (Piper nigrum L.) grown in the Brazilian Amazon region, variety Bragantina, using the standard oven method. The results of the experiment indicated that the Bragantina variety of black pepper presented water contents within the standards established by the normative number 10 of May 2006, with samples similar among themselves and without significant variations after drying. The exception was the thirteenth sample, which presented a lower average water content, possibly due to differences in harvesting or processing. It is concluded that the quality of the Bragantina variety is stable and meets the requirements of the regulation.A pimenta-do-reino é uma importante cultura agrícola no Brasil e em outros países em desenvolvimento. A secagem adequada da pimenta é crucial para garantir a qualidade e segurança do produto. O objetivo do experimento foi definir o teor de água no grão da pimenta do reino (Piper nigrum L.) cultivado na região Amazônica brasileira, variedade Bragantina, utilizando o método padrão da estufa. Os resultados do experimento indicaram que a variedade Bragantina de pimenta-do-reino apresentou teores de água dentro dos padrões estabelecidos pela normativa nº 10 de maio de 2006, com amostras similares entre si e sem variações significativas após a secagem. A exceção foi a décima terceira amostra, que apresentou uma média menor de teor de água, possivelmente devido a diferenças na colheita ou processamento. Conclui-se que a qualidade da variedade Bragantina é estável e atende às exigências da normativa