Neonatal Fc receptor induces intravenous immunoglobulin growth suppression in Langerhans cell histiocytosis.

The neonatal Fc receptor (FcRn) plays a role in trafficking IgG and albumin and is thought to mediate intravenous immunoglobulin (IVIG) therapy for certain diseases. IVIG can be used for the treatment of human Langerhans cell histiocytosis (LCH); however, the mechanism remains unclear. The expression and function of FcRn protein have not been studied in LCH, though the expression of FcRn messenger RNA (mRNA) have been reported. In this report, we confirmed the expression of FcRn in 26 of 30 pathological cases (86.7%) diagnosed immunohistochemically as LCH. The expression was independent of age, gender, location, multi- or single-system, and the status of BRAFV600E immunostaining. We also confirmed the expression of FcRn mRNA and protein in the human LCH-like cell line, ELD-1. FcRn suppressed albumin consumption and growth of IVIG preparation-treated ELD-1 cells, but not of IVIG preparation-untreated or FcRn-knockdown ELD-1 cells. In addition, FITC-conjugated albumin was taken into Rab11-positive recycle vesicles in mock ELD-1 cells but not in FcRn-knockdown ELD-1 cells. IVIG preparation prolonged this status in mock ELD-1 cells. Therefore, ELD-1 recycled albumin via FcRn and albumin was not used for metabolism. Our results increase our understanding of the molecular mechanism of IVIG treatment of LCH.

A unique case of a typical pancreatic ductal adenocarcinoma that initially presented with a cystic component but underwent morphological changes.

A 66-year-old man was initially suspected of having a microcystic serous cystic neoplasm based on magnetic resonance imaging findings of a multifocal mass measuring 46 mm in the pancreatic head, with a cystic component showing a high signal on T2-weighted images. The tumor marker levels were within normal limits. However, contrast-enhanced computed tomography revealed thick cyst walls with delayed staining, which was atypical for serous cystic neoplasms; therefore, the patient was followed up closely. Twenty-two months later, the delayed contrast area was enlarged, carbohydrate antigen 19-9 levels were elevated, and 18 F-fluorodeoxyglucose-positron emission tomography revealed increased accumulation, indicating a potentially malignant lesion. Pancreatoduodenectomy was performed and histopathological examination confirmed the diagnosis of normal-type pancreatic carcinoma with predominantly poorly differentiated cells. Based on the pathological findings and a literature review, it is highly likely that this case represents pancreatic ductal adenocarcinoma with a cystic structure from the beginning. While distinguishing pancreatic ductal adenocarcinoma from other pancreatic cystic tumors, such as serous cystic neoplasms, is critical owing to differing treatments and prognoses, caution is warranted as they may exhibit similar imaging features, as observed in our patient.

Characterization of proteinous coagulant in Moringa tree seeds for water purification: Stepwise laboratory exercise for high-school students.

Coagulation is an important process in the context of water purification; and the seed protein of the moringa tree (Moringa oleifera) is a remarkably effective coagulant. The laboratory course described here is designed to provide high-school students with a stepwise, hands-on experience in investigating the protein-rich coagulant found in Moringa seeds. First, the seed powder was applied to model polluted water containing fine clay, food dyes, copper sulfate, and bacteria. This treatment changed the polluted water into clear water via coagulation; all students were convinced that the coagulation-inducing agent was a thermostable cationic protein. Finally, basic biochemical techniques (e.g., chromatographic separation and electrophoresis) were used to show that the target coagulant is a dimeric protein composed of 6.5 and 4.5 kDa subunits. Overall, this made it possible for the students to gain a deeper understanding (more comprehensive than the information taught in formal classes) of protein structure and its real-world implications. This stepwise exercise can be applied to research-based learning programs in high school, as it is an effective learning tool.

Analysis of functional ingredients of tempe-like fermented Moringa oleifera seeds (Moringa tempe) prepared with Rhizopus species.

Tempe is a fermented food prepared by fermenting soybeans with Rhizopus species. However, there have recently been concerns about the stable supply of raw soybeans due to global warming and other factors. Moringa is a plant whose cultivation area is expected to expand in the future, and its seeds contain abundant proteins and lipids, and thus could be used as an alternative to soybeans. To develop a novel functional Moringa food, we fermented dehulled Moringa seeds with Rhizopus oligosporus and Rhizopus stolonifer using the solid fermentation method of tempe and investigated changes in the functional components, such as free amino acids and polyphenols, of the respective obtained Moringa tempe Rm and Rs. After 45 h of fermentation, the total content of free amino acids, mainly including gamma-aminobutyric acid and l-glutamic acid, in Moringa tempe Rm was about three times higher, while that in Moringa tempe Rs was almost the same, compared to that in unfermented Moringa seeds. Moreover, after 70 h of fermentation, both Moringa tempe Rm and Rs had approximately four times higher polyphenol content and significantly higher antioxidant activity than did unfermented Moringa seeds. Further, the content of each residual chitin-binding protein of defatted Moringa tempe Rm and Rs was almost the same as that of unfermented Moringa seeds. Taken together, Moringa tempe was rich in free amino acids and polyphenols, exhibited better antioxidant activity, and retained the levels of its chitin-binding proteins, suggesting that Moringa seeds could be used as an alternative to soybean for tempe preparation.