C-C Bond formation in the purine 8-position by addition of allylmetals

8-Substituted purines have been extensively studied as for example anticancer or antiviral drugs. C-C Bond formation at the purine 8-position has been most commonly done via 8-halopurines, e.g. Pd-catalyzed coupling reactions. Meanwhile, direct conversion of purines not substituted at C-8 to 8-alkylpurines seems to be promising but there are few reports in the literature. In this thesis, addition of an allylmetallic reagent to 8-unsustituted purines followed by oxidation of the adduct to form 8-allylated purines will be discussed

THỰC TRẠNG GIẢI PHÓNG MẶT BẰNG ĐẤT NGHĨA TRANG, NGHĨA ĐỊA DỰ ÁN KHU ĐÔ THỊ TÂY NAM XÃ NHƠN LÝ, KHU KINH TẾ NHƠN HỘI, TỈNH BÌNH ĐỊNH

This study used data collection methods, expert methods, and methods of synthesizing, processing, and analyzing data and maps and charts, with a management and practical approach combined with an approach from a cultural perspective. The research results show that the Southwest urban area project in Nhon Ly commune has 1,100 graves affected, with 78.93% of the cemetery and graveyard land area recovered. People whose graves are subject to relocation will be compensated, supported with graves, architectural objects, and grave moving expenses, and will be allocated land to build graves in the reburial area. Interview results show that 100% of people are satisfied with the evaluation criteria of implementation personnel, process, time, and grave relocation plan. However, the standard deviation CS1, CS2 with CV>1 shows that households' opinions on compensation and support costs do not have a high consensus. On the other hand, the project is behind schedule. The study has proposed solutions that have implications for supplementing legal policies and law enforcement organizations to improve the effectiveness of cemetery and graveyard land clearance in the study area.Nghiên cứu này sử dụng phương pháp thu thập số liệu, phương pháp chuyên gia, phương pháp tổng hợp, xử lý, phân tích số liệu và bản đồ, biểu đồ, với cách tiếp cận dưới góc độ quản lý, thực tiễn kết hợp tiếp cận dưới góc độ văn hóa. Kết quả nghiên cứu cho thấy, dự án khu đô thị Tây Nam xã Nhơn Lý có 1.100 mộ bị ảnh hưởng, với 78,93% diện tích đất nghĩa trang, nghĩa địa bị thu hồi. Người có mồ mả thuộc diện di dời được bồi thường, hỗ trợ mồ mả, vật kiến trúc, chi phí di chuyển mồ mả, đồng thời được giao đất xây dựng mồ mả tại khu cải táng. Kết quả phỏng vấn cho thấy, 100% người dân hài lòng với các tiêu chí đánh giá về nhân sự thực hiện, quy trình, thời gian và kế hoạch di dời mồ mả. Tuy nhiên, độ lệch chuẩn CS1, CS2 với CV>1 cho thấy ý kiến các hộ dân về chi phí bồi thường, hỗ trợ chưa có sự đồng thuận cao. Mặt khác, dự án chậm tiến độ. Nghiên cứu đã đề xuất các giải pháp, trong đó có hàm ý bổ sung chính sách pháp luật và tổ chức thực thi pháp luật nhằm nâng cao hiệu quả công tác giải phóng mặt bằng đất nghĩa trang, nghĩa địa tại địa bàn nghiên cứu

How has Learning Motivation of University Students in Vietnam Changed during COVID-19 Pandemic?

With the data from 2,082 students at National Economics University, this article focuses on assessing the decline in learning motivation of undergraduates during the fourth wave of COVID-19 in Vietnam. Using exploratory factor analysis (EFA), descriptive statistics, and One_Way ANOVA tests, it was evident that the decline in learning motivation was noticeable in most students surveyed. Specifically, 36.1% of the survey respondents experienced severe demotivation with all 4 expressions “Distracted”, “Exhausted”, “Uninterested” and “Lack of responsibility for learning”. Furthermore, the level of motivation decline tended to rise significantly among the groups of students with the following characteristics: first-year students, male gender, and low academic performance. The abovementioned results alert educational and training institutions to pay proper attention and comprehensively evaluate the learning motivation of their students. Moreover, supportive measures should be implemented to improve learning motivation for the young in the “post-COVID-19” period

Development of a highly sensitive point‐of‐care test for African swine fever that combines EZ‐Fast DNA extraction with LAMP detection: Evaluation using naturally infected swine whole blood samples from Vietnam

[Background] While early detection and early containment are key to controlling the African swine fever (ASF) pandemic, the lack of practical testing methods for use in the field are a major barrier to achieving this feat. [Objectives] To describe the development of a rapid and sensitive point-of-care test (POCT) for ASF, and its evaluation using swine whole blood samples for field settings. [Methods] In total, 89 swine whole blood samples were collected from Vietnamese swine farms and were performed the POCT using a combination of crude DNA extraction and LAMP (loop-mediated isothermal amplification) amplification. [Results] The POCT enabled crude DNA to be extracted from swine whole blood samples within 10 min at extremely low cost and with relative ease. The entire POCT required a maximum of 50 min from the beginning of DNA extraction to final judgment. Compared to a conventional real-time PCR detection, the POCT showed a 1 log reduction in detection sensitivity, but comparable diagnostic sensitivity of 100% (56/56) and diagnostic specificity of 100% (33/33). The POCT was quicker and easier to perform and did not require special equipment. [Conclusions] This POCT is expected to facilitate early diagnosis and containment of ASF invasion into both regions in which it is endemic and eradicated

SECONDARY METABOLITES FROM MICROMONOSPORA SP. (G044)

In the course of our screening program, the EtOAc extract of a Micromonospora sp. (strain G044) from sponge Tethya aurantium of the sea of Côtô - Thanh Lân exhibited antimicrobial activity against Enterococcus faecalis, Bacillus cereus and Candida albicans. In this paper, we reported the isolation and structural elucidation of six secondary metabolites Cyclo-(Pro-Trp) (1), Cyclo-(Pro-Met) (2), Cyclo-(Pro-Val) (4), N-acetyltryptamine (3), uridine (5), and 2-phenylacetic acid (6) from the cultures broth of Micromonospora sp. (strain G044). The structures of 1 – 6 were determined by analyses of MS and 2D NMR data. All compounds were evaluated for their antimicrobial activity against a panel of clinically significant microorganisms. Compound 1 inhibited Escherichia coli with a MIC value of 128 µg/ml

Penetrating Keratoplasty for Keratoconus in Vietnamese Patients

BACKGROUND: Keratoconus is an ectatic corneal disorder that can impair the visual acuity. Up to now, penetrating keratoplasty (PK) remains the most common surgical procedure to treat severe keratoconus. In Vietnam, most keratoconus patients come to visit doctor at severe stage and were treated by PK, so we conduct this study. AIM: To evaluate the results of PK for keratoconus in Vietnamese patients. METHODS: This was a retrospective study of 31 eyes with keratoconus who underwent PK in VNIO from January 2005 to December 2014. RESULTS: The average visual acuity was 0.86 ± 0.37 logMAR (20/145). In the group of patients without amblyopia, best spectacle-corrected visual acuity of 20/60 or better was recorded in 75.9% of eyes and 93.1% of eyes achieved a best corrected visual acuity with hard contact lenses of 20/40 or better. Mean postoperative corneal power was 43.8 ± 4.5D. Mean corneal astigmatism was 5.9 ± 2.7D. 94.6% of grafts remained clear. Posterior subcapsular cataract developed in 22.6% of eyes. Graft rejection was recognized in 12.9% of eyes. CONCLUSION: PK is an effective procedure with high rate of graft survival for keratoconus patients. However, patients should be aware of the necessary of optical correction to gain the best VA after surgery

Chemical constituents from fruits of Hydnocarpus hainanensis Merr. (Flacourtiaceae) in Vietnam

Five compounds were isolated from the fruits of Hydnocarpus hainanensis Merr. Sleum. (Flacourtiaceae). Their structures were determined by spectroscopic analysis including MS and NMR. The isolates were identified as taraktophyllin (1), hydnocarpic acid (2), 3,4-dihydroxybenzyl alcohol (3), 3,4-dihydroxybenzoic acid (4) and 3-hydroxy-4-methoxybenzoic acid (5)

Secondary metabolites from Micromonospora ectrinospora G017

Eight  compounds, cyclo-(Pro-Tryp) (1), N-[2-(1H-indol-3-yl)-2-oxo-ethyl] acetamide (2), cyclo-(Pro-Tyr) (3), cyclo-(Pro-Phe) (4), cyclo-trans-4-OH-(Pro-Phe) (5), cyclo-(Pro-Leu) (6), cyclo-(Pro-Val) (7), and  uracil (8) were isolated from the culture broth of the marine Micromonospora ectrinospora G017 strain. The structures of the isolated compounds were established on the basis of their spectral data, including mass spectrometry and NMR

Terpenoids from leaves of Viburnum sambucinum Reinw. ex. Blume (Caprifoliaceae)

Six compounds were isolated from the leaves of Viburnum sambucinum Reinw. ex Blume (Caprifoliaceae).  The structures of the isolates were determined by spectroscopic analysis including MS and NMR. Accordingly, the isolated compounds were identified as a-amyrin (1), ursolic acid (2), 3β,28-dihydroxy-urs-12-ene (3), oleanolic acid (4), 16β-hydroxylup-20(29)-ene-3-one (5) and trans-2-phyten-1-ol (6)

Discrepancies in Infectivity of Flavivirus and SARS-CoV-2 Clinical Samples: An Improved Assay for Infectious Virus Shedding and Viremia Assessment

Infectivity and neutralizing antibody titers of flavivirus and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are frequently measured using the conventional plaque assay. While the assay is useful in the determination of infectivity, conventional plaque assays generally possess lower sensitivity and are time-consuming compared to nucleic acid amplification tests. In this study, a microcrystalline cellulose (MCC), Avicel, was evaluated as an alternative to the conventional virus overlay medium, methylcellulose, for a plaque assay. The plaque assay was performed using dengue and COVID-19 clinical samples and laboratory-established flavivirus and SARS-CoV-2 strains. In virus titration of clinical samples, the plaques were significantly larger, and the virus titers were higher when Avicel MCC-containing overlay medium was used than with conventional methylcellulose overlay medium. In addition, for some clinical samples and laboratory virus strains, infectious particles were detected as plaques in the Avicel MCC-containing medium, but not in the conventional methylcellulose medium. The results suggest that the viremia titer determined using the new overlay medium containing Avicel MCC may better reflect the innate infectious and plaque-forming capabilities of clinical samples and better reflect virus infectivity