PRELIMINARY STUDY ON CHEMICAL MECHANISM OF DECREASE OF TETRODOTOXIN CONTENT IN OVARIES OF A PUFFER FISH Lagocephalus inermis (Temminck and Schlegel, 1850) FERMENTED WITH RICE BRAN

Tetrodotoxins in salted and fermented ovaries with rice bran of a puffer fish Lagocephalus inermis (Temminck Schlegel, 1850) during five months were determined by high-performance liquid chromatography with fluorometric detector (HPLC- FLD). The analysed results showed that the original ovaries contained only tetrodotoxin with content of 7.59 µg/g fresh weight. 4,9-Anhydrotetrodotoxin - an isomer which is less toxic than tetrodotoxin has been found in all ovary samples since the second month. Tetrodotoxin in the ovaries disappeared in the 4th month of the experiment. In addition, 4,9-anhydrotetrodotoxin level in ovaries increased during fermentation. The present study contributes to clarifying the chemical mechanism of decreasing tetrodotoxin content in fermented ovary of puffer fish.Tetrodotoxins in salted and fermented ovaries with rice bran of a puffer fish Lagocephalus inermis (Temminck and Schlegel, 1850) during five months were determined by high-performance liquid chromatography with fluorometric detector (HPLC- FLD). The analysed results showed that the original ovaries contained only Tetrodotoxin with content of 7.59 µg/g fresh weight. 4,9-Anhydrotetrodotoxin- an isomer which is less toxic than Tetrodotoxin has been found in all ovary samples since the second month. Tetrodotoxin in the ovaries disappeared in the 4th month of the experiment. In addition, 4,9-Anhydrotetrodotoxin level in ovaries increased during fermentation. The present study contributes to clarify the chemical mechanism of decreasing Tetrodotoxin content in fermented ovary of puffer fish

MỘT SỐ ĐẶC TÍNH CỦA CANXI HYDROXYAPATIT CHIẾT XUẤT TỪ XƯƠNG CÁ NGỪ VẰN Katsuwonus pelamis

This paper is concerned with certain properties of calcium hydroxyapatite from skipjack tuna bone (Katsuwonus pelamis) which are by-products of fish export industry. Hydroxyapatite Ca10(PO4)6(OH)2 and β-tricalcium phosphate Ca3(PO4)2, the high-value compounds, have been successfully extracted from skipjack tuna bones. The bones were heated at different temperatures of 600oC, 900oC, 1200oC. While at 600oC hydroxyapatites were obtained with Ca/P ratio of 1.658, comparable to the value of 1.67 found in human bone; the hydroxyapatite crystals of average size of 0.25 µm were formed with the same size distribution. In case of heated bone samples at 900°C and 1200°C, the calcium formed were biphasic calcium phosphate composed of hydroxyapatite and β-tricalcium phosphate; the Ca/P ratio was between 1.660–1.665; the calcium crystals of more than 1 µm were highly porous and connected to each other in priority orientation of tube direction.Bài báo này trình bày kết quả nghiên cứu về một số đặc tính của canxi hydroxyapatit chiết xuất từ xương cá ngừ Katsuwonus pelamis, một sản phẩm phụ từ ngành xuất khẩu thịt cá ngừ. Các hợp chất có giá trị là hydroxyapatit Ca10(PO4)6(OH)2 và β-tricanxi phosphat β-TCP Ca3(PO4)2 đã được chiết xuất thành công từ xương cá ngừ vằn. Xương cá ngừ được nung ở các nhiệt độ khác nhau 600, 900 và 1.200oC. Dạng canxi thu được khi nung mẫu ở 600oC là hydroxyapatit với tỉ lệ Ca/P 1,658 gần với tỉ lệ Ca/P 1,67 trong xương người; các tinh thể hydroxyapatit có kích thước trung bình 0,25 µm và sự phân bố kích thước tương đối đồng đều. Đối với mẫu xương được xử lý ở 900 và 1.200oC, canxi thu được là hỗn hợp hai pha hydroxyapatit Ca10(PO4)6(OH)2 và β-tricanxi phosphat Ca3(PO4)2; tỉ lệ Ca/P từ 1,660–1,665, các tinh thể canxi có độ xốp cao và liên kết với nhau theo hướng ưu tiên kiểu hình ống với kích thước lớn hơn 1 µm

Attitudes About Sex and Marital Sexual Behavior in Hai Duong Province, Vietnam

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/74926/1/j.1728-4465.2005.00047.x.pd

Global, regional, and national incidence of six major immune-mediated inflammatory diseases: findings from the global burden of disease study 2019

Background The causes for immune-mediated inflammatory diseases (IMIDs) are diverse and the incidence trends of IMIDs from specific causes are rarely studied. The study aims to investigate the pattern and trend of IMIDs from 1990 to 2019. Methods We collected detailed information on six major causes of IMIDs, including asthma, inflammatory bowel disease, multiple sclerosis, rheumatoid arthritis, psoriasis, and atopic dermatitis, between 1990 and 2019, derived from the Global Burden of Disease study in 2019. The average annual percent change (AAPC) in number of incidents and age standardized incidence rate (ASR) on IMIDs, by sex, age, region, and causes, were calculated to quantify the temporal trends. Findings In 2019, rheumatoid arthritis, atopic dermatitis, asthma, multiple sclerosis, psoriasis, inflammatory bowel disease accounted 1.59%, 36.17%, 54.71%, 0.09%, 6.84%, 0.60% of overall new IMIDs cases, respectively. The ASR of IMIDs showed substantial regional and global variation with the highest in High SDI region, High-income North America, and United States of America. Throughout human lifespan, the age distribution of incident cases from six IMIDs was quite different. Globally, incident cases of IMIDs increased with an AAPC of 0.68 and the ASR decreased with an AAPC of −0.34 from 1990 to 2019. The incident cases increased across six IMIDs, the ASR of rheumatoid arthritis increased (0.21, 95% CI 0.18, 0.25), while the ASR of asthma (AAPC = −0.41), inflammatory bowel disease (AAPC = −0.72), multiple sclerosis (AAPC = −0.26), psoriasis (AAPC = −0.77), and atopic dermatitis (AAPC = −0.15) decreased. The ASR of overall and six individual IMID increased with SDI at regional and global level. Countries with higher ASR in 1990 experienced a more rapid decrease in ASR. Interpretation The incidence patterns of IMIDs varied considerably across the world. Innovative prevention and integrative management strategy are urgently needed to mitigate the increasing ASR of rheumatoid arthritis and upsurging new cases of other five IMIDs, respectively. Funding The Global Burden of Disease Study is funded by the Bill and Melinda Gates Foundation. The project funded by Scientific Research Fund of Sichuan Academy of Medical Sciences & Sichuan Provincial People's Hospital (2022QN38)

Intermolecular amidation of unactivated sp2 and sp3 C-H bonds via palladium-catalyzed cascade C-H activation/nitrene insertion

This communication describes the Pd(OAc)2-catalyzed intermolecular amidation reactions of unactivated sp2 and sp3 C-H bonds using primary amides and potassium persulfate. The substrates containing a pendent oxime or pyridine group were amidated with excellent chemo- and regioselectivities. It is noteworthy that reactive C-X bonds were well-tolerated and a variety of primary amides can be effective nucleophiles for the Pd-catalyzed C-H amidation reactions. For the reaction of unactivated sp3 C-H bonds, β-amidation of 1° sp3 C-H bonds versus 2° C-H bonds is preferred. The catalytic reaction is initiated by chelation-assisted cyclopalladation involving C-H bond activation. Preliminary mechanistic study suggested that the persulfate oxidation of primary amides should generate reactive nitrene species, which then reacted with the cyclopalladated complex. Copyright © 2006 American Chemical Society.link_to_subscribed_fulltex

Tác phẩm chọn lọc, số 1 : Tháng 1-1995

164 tr.; 19 cm