Transformation Chlorophyll a of Spirulina platensis to Chlorin e6 Derivatives and Several Applications

BACKGROUND: Spirulina platensis contains a large amount of chlorophylls, chlorophyll a, that are starting materials to synthesize functionalized chlorins. Chlorin e6 (Ce6) as well as its derivatives are second generation sensitizers using in photodynamic therapy (PDT) of various cancers. In this study, we transfer chlorophyll a of S. platensis to Ce6derivatives and determine their several applications. AIM: to evaluate the effects of Ce6 derivatives to treat cancer cells. METHODS: Ce6 trimethylester was created from methyl pheophorbide a2 in S. platensis provided by the Hidumi Company, Nghe An province, Viet Nam. Hela cells were incubated with Ce6 trimethylester and the irradiated with the diode laser dose of 1.2 J/cm2/min through the system of filters £ 650 nm. MTT assay and clonogenic assay were used to determine survival rate and cloning efficiency of cells. Antimicrobial effect of Ce6 trimethylester with halogen light were studied with Propionibacterium acnes VTCC 0218 and Staphylococcus aureus VTCC 0173. RESULTS: From dry biomass (700 g) of S. platensis, after extracting chlorophyll a and methanolysis, 4.2 g of methyl pheophorbide a was obtained. The reaction to give Ce6 trimethylester with 82% yield was performed with potassium hydroxide (KOH) in MeOH/THF/CHCl3. After irradiation with a 650 nm laser at 1.2 J, the cell viability in all samples decreased with Ce6 trimethylester treatment, the survival declining trend of Hela cells treated with Ce6 trimethylester were proportional when concentration of Ce6 trimethylester increased. The rate of colony formation was declined as the concentration of Ce6 trimethylester treated was increased. The growth of both S. aureus and P. acnes can be inactivated by Ce6 trimethylester PDT. The MIC99 value against P. acnes VTCC 0218 and S. aureus VTCC 0173 of Ce6 trimethylester with halogen light was 1.25 μg/ml. CONCLUSION: The Ce6 trimethylester from S. platensis cultivated in Viet Nam could be used as a potential photosentizer for photodynamic therapy for treatment of cancer and acne

ĐIỆN CỰC NANO CẤU TRÚC 3D - PHÂN LỚP DỊ THỂ CỦA CdS/ZnO/Pt/WO3 TRONG VIỆC NÂNG CAO HIỆU SUẤT TÁCH NƯỚC QUANG ĐIỆN HÓA

In this work, we report the synthesis of the hierarchical structure of a CdS/ZnO/Pt/WO3 electrode for photoeletrochemical water splitting application. The photoanode was synthesized via the hydrothermal and atomic layer deposition methods. The morphological and structural properties of CdS/ZnO/Pt/WO3 nanoplates were carefully investigated by using SEM, TEM, and XRD techniques. The CdS/ZnO/Pt/WO3-based photoelectrode has a photocurrent density of 8,5 mA·cm-2 and a photoconversion efficiency of 7.9% at a supplied potential of –0,85 V in a 0.5 M Na2S solution. This photocurrent density is twice higher than that of the CdS/ZnO/FTO electrode. Due to built-in potential and efficiently collecting the photo-carriers generated from the ZnO/CdS heterojunction under illumination, the CdS/ZnO/Pt/WO3 electrode exhibits enhanced performance of the photoelectrochemical cell. This is a promising approach to the synthesis of heterojunction layers of semiconductor together with nanostructures for fabricating photoelectrodes of the photoelectrochemical cell to enhance hydrogen production efficiency.Trong bài báo này, chúng tôi nghiên cứu chế tạo điện cực có cấu trúc 3D phân lớp dị thể (cây – cành – nhánh) CdS/ZnO/Pt/WO3 ứng dụng cho tách nước quang điện hóa. Điện cực được tổng hợp bằng phương pháp thủy nhiệt và lắng đọng lớp nguyên tử. Hình thái học, cấu trúc tinh thể, và thành phần nguyên tố của điện cực này được nghiên cứu bằng kính hiển vi điện tử quét (FE–SEM), kính hiển vị điện tử truyền qua (HR–TEM) và nhiễu xạ tia X (XRD). Nghiên cứu tính chất quang điện hóa của cấu trúc CdS/ZnO/Pt/WO3, chúng tôi thu được mật độ dòng quang điện là 8,5 mA·cm-2 và hiệu suất chuyển đổi năng lượng ánh sáng mặt trời thành năng lượng hydro 7,9 %% tại thế cung cấp –0,85 V trong dung dịch chất điện ly Na2S với nồng độ 0,5 mol/L. Cấu trúc 3D phân lớp này có mật độ dòng quang điện của điện cực cao hơn gấp hai lần so với các cấu trúc CdS/ZnO trên điện cực thủy tinh phủ oxit thiếc pha tạp bằng flo. Đây là một hướng tiếp cận rất hứa hẹn tổng hợp các cấu trúc nano phân lớp dị thể nhằm nâng cao hiệu quả sản xuất hydro

The role of technological innovation and cleaner energy towards the environment in ASEAN countries: proposing a policy for sustainable development goals

The association between economic growth (EG) and environmental degradation (ED) has been highlighted extensively in prior studies. However, investigation regarding ‘technological innovation and clean energy role’ in dealing with environmental concerns has comprised limited context while considering the ASEAN economies under sustainable development goals. Therefore, the study attempts to investigate the phenomenon by using CS-ARDL analysis under short as well as long run. The findings through CSARDL in long- and short-run indicate that REN have impact carbon emission and ecological footprints negatively. Additionally, the EG in targeted economies is causing a higher level of CE and ecological footprints. Whereas, GDP2ofund to be significant in lowering the ED in the form of CE and ecological footprints. It is suggested that policies related to CE through EG should be developed in order to control the environmental issues in the future

An Assessment of the Values of French Colonial Townhouses in Hanoi Towards A More Sustainable Conservation

As the capital city of French Indochina, Hanoi was well planned by the French and immensely invested in the construction of public buildings as well as houses. In addition to public buildings and villas designed in French colonial styles that shaped the so-called distinctive architectural heritage in Hanoi throughout the colonial years, a large number of townhouses built during 1920 - 1950 which formed the cityscape of Hanoi in the first half of the 20th century should be noted. After nearly 70 years since the French army withdrew from the city, the number of French townhouses has considerably decreased. The remaining houses have shown that this is a real “treasure” that needs to be conserved because of their important values, not only in terms of urban architecture but also in cultural and historical aspects. However, a fact requiring special attention is that French townhouses in Hanoi - unlike French public buildings and villas - have not yet been recognised as heritage so that they can be kept to avoid the risk of deterioration or demolition under the impact of rapid urbanisation in the market economy. One of the main reasons for this negative urban development is that there has been no concrete or comprehensive rating system to assess the values of those townhouses which will closely correspond to their characteristics and contexts. Therefore, the authors - based on site surveys and by applying some appropriate methods such as expert consultations and case studies - have developed a full set of criteria to help evaluate those remaining townhouses as accurately as possible. This system can be used as a basis for a systematic assessment and classification towards a more effective conservation and even promoting the values of those townhouses with regard to the development of a modern society and in consideration of sustainable heritage conservation as a mainstream in the world.

Genetic variation and outcrossing rate of Dipterocarpus dyeri in the Tan Phu tropical rain forest (Dong Nai), Vietnam

Dipterocarpus dyeri (Dipterocarpaceae) is widely distributed in lowland rainforests in southeastern Vietnam. Due to over- exploitation and habitat destruction in the 1980s and 1990s, this species is listed as threatened. Understanding the genetic variation and mating rate among D. dyeri population that occurs in forest patches is necessary to establish effectively conservation strategies for this species. To conserve the species in tropical forests, genetic diversity and mating rate were investigated using eight microsatellites (single sequence repeat, SSR) as markers. All of the eight loci were polymorphic. A total of 36 different alleles were observed across the loci screened. The SSR data indicated high genetic diversity (NA = 4.5; HO = 0.542 and HE = 0.667) and high inbreeding value, FIS= 0,182. The mating system parameters were determined using the mixed mating model and the results indicated high outcrossing rate (tm=0.81 and ts=0.675) and lowselfing rate (0.19). Difference of tm-ts value indicated that inbreeding contributed to selfing rate for this species in the Tan Phu tropical rain forest. The results reflected that D. dyeri habitat in this area has been restored and the number of individuals was high, about 500 individuals. However, seedlings were not found so far in this study. These results indicated the importance of conserving of the genetic resources of Dipterocarpus dyeri species in the Tan Phu rain forest. The conservation strategy should include an establishment of an ex-situ conservation site with new big population for this species from all genetic groups, which might improve its fitness under different environmental stresses. 

ĐẶC ĐIỂM KHÁNG KHÁNG SINH CỦA VI KHUẨN STREPTOCOCCUS SUIS PHÂN LẬP TỪ LỢN BẢN ĐỊA NUÔI TRÊN ĐỊA BÀN HUYỆN A LƯỚI, TỈNH THỪA THIÊN HUẾ

Streptococcus suis (S. suis) is a Gram-positive bacterium, a common cause of disease in pigs, and is a zoonotic pathogen. The objective of this study was to determine the infection rate, and antimicrobial resistance characteristics of S. suis isolated from local pigs in A Luoi district, Thua Thien Hue province. S. suis was isolated using on blood agar, and identified by PCR method; the antimicrobial resistance was assessed by disk diffusion method and the antimicrobial resistance genes were detected by PCR. The results showed that 33,33% of the samples were positive for S. suis. Most of S. suis isolates were susceptible to neomycin, gentamicin, and erythromycin; but resistant to penicillin, amoxicillin, ampicillin, and tetracycline. The results also showed that, amoxicillin and tetracycline resistance were significantly positively correlated with penicillin resistance; enrofloxacin and gentamicin were significantly negatively correlated with penicillin and ampicillin. A high percentage of S. suis isolates carried gyrA and parC genes (75.61%), Sul1 (70.73%), and ermB (29.27%). There was 92.68% of S. suis isolates showed multidrug resistance and 82.93% of the isolates carried multiple antimicrobial resistance genes.Streptococcus suis (S. suis) là vi khuẩn Gram dương gây bệnh ở lợn và có thể lây sang người. Mục tiêu của nghiên cứu là xác định tỷ lệ nhiễm, đặc điểm kháng kháng sinh của S. suis phân lập được từ lợn bản địa ở A Lưới, Thừa Thiên Huế. S. suis được phân lập trên môi trường thạch máu, định danh bằng phương pháp PCR; kháng kháng sinh được đánh giá bằng phương pháp khuếch tán trên thạch và gene kháng kháng sinh được phát hiện bằng phương pháp PCR. Kết quả cho thấy, có 41/123 (33,33%) con bị nhiễm S. suis. Tỷ lệ cao chủng S. suis nhạy cảm với streptomycin, neomycin, gentamicin và erythromycin; nhưng cũng có tỷ lệ cao đã kháng lại penicillin, amoxicillin, ampicillin và tetracycline. Mối tương quan chặt chẽ giữa tính kháng với amoxicillin và penicillin; tetracycline và penicillin; giữa tính nhạy cảm với enrofloxacin và tính kháng lại penicillin; giữa tính nhạy cảm với gentamicin và tính kháng với ampicillin của các chủng S. suis đã được phát hiện. Tỷ lệ cao các chủng S. suis mang gene gyrA và parC (75,61%), Sul1 (70,73%), và ermB (29,27%). Có 92,68% số chủng S. suis kháng lại nhiều loại kháng sinh và 82,93% chủng mang nhiều gene kháng kháng sinh

Validation of Mesocyclops (Copepoda) and community participation as an effective combination for Dengue control in Northern Vietnam

The “Programme Meso-Vietnam” was implemented in Vietnam from October 2007 to December 2010 to reduce dengue and dengue hemorrhagic fever incidence and to improve the quality of life in the four project communes. This dengue control project was based on biological control using Mesocyclops, a larvivorous micro-crustacean, as well as on the establishment of a strong community involvement to educate the population on dengue transmission and to reduce Aedes breeding by removal of containers. During three years, a network of collaborators was responsible for introducing Mesocyclops in all the containers defined as key breeding-sites, and regular activities such as community training workshops, school programmes, clean-up campaigns and health promotion through IEC programmess were performed. To make this programme sustainable, local leadership has been strengthened as well. The use of these larvivorous micro-crustaceans as a biological control strategy against dengue over the medium and long term, when combined with community participation and effective health promotion, demonstrated a significant reduction in dengue vector populations and dengue cases.  In Vietnam, this study reconfirms that there is an ecological alternative to systematic use of insecticides to control dengue vector population. (Abstract word count: 186)Le " Programme Meso-Vietnam " a été mis en œuvre au Vietnam entre octobre 2007 et décembre 2010. Ce programme vise à réduire l'incidence de la dengue et de la fièvre hémorragique de la dengue et à améliorer la qualité de vie dans les quatre communes sélectionnées pour le projet. Ce projet de lutte contre la dengue était basé sur un contrôle biologique assuré par des Mésocyclopes, micro-crustacés larvivores, et sur l'établissement d'une forte implication de la communauté pour éduquer la population sur la transmission de la dengue et pour réduire la reproduction des moustiques Aedes par élimination des conteneurs leur servant de site de ponte. Pendant trois ans, un réseau de collaborateurs a été chargé d'introduire des Mésocyclopes dans tous les conteneurs définis comme des sites de reproduction clés, et des activités régulières telles que des ateliers de formation communautaires, des programmes scolaires, des campagnes de nettoyage et des activités de promotion de la santé via les programmes IEC ont été mises en place. En outre, pour assurer la pérennité de ce programme, le leadership local a été renforcé. L'utilisation de ces micro-crustacés larvivores comme stratégie de contrôle biologique de la dengue à moyen et long terme, associée à une participation communautaire et à une promotion efficace de la santé, a permis d'aboutir à une réduction significative des populations vecteurs de la dengue et des cas de dengue. Au Vietnam, cette étude confirme une fois de plus qu'il existe une alternative écologique à l'utilisation systématique d'insecticides pour lutter contre les vecteurs de la dengue.El “Programa Meso-Vietnam” se implementó en Vietnam desde octubre de 2007 hasta diciembre de 2010 para reducir la incidencia del dengue y la fiebre hemorrágica del dengue y para mejorar la calidad de vida en los cuatro municipios del proyecto. Este proyecto de control del dengue se basaba en el control biológico usando Mesocyclops, un microcrustáceo larvívoro, así como en el establecimiento de una fuerte implicación comunitaria para educar a la población sobre la transmisión del dengue y para reducir la cría de Aedes mediante la eliminación de recipientes. Durante tres años, una red de colaboradores fue responsable de la introducción de Mesocyclops en todos los recipientes definidos como sitios clave para la cría, y se realizaron actividades regulares tales como talleres de formación comunitaria, programas escolares, campañas de limpieza y promoción de la salud a través de programas de IEC. Para hacer sostenible este programa, también se reforzó el liderazgo local. El uso de estos microcrustáceos larvívoros como estrategia de control biológico contra el dengue a medio y largo plazo demostró una reducción significativa de las poblaciones de vectores del dengue y los casos de dengue cuando se combinaba con la participación comunitaria y la promoción eficaz de la salud. En Vietnam, este estudio vuelve a confirmar que existe una alternativa ecológica al uso sistemático de insecticidas para controlar la población de vectores del dengue

Anatomical Characteristics and Variants of Prostatic Artery in Patients of Benign Hyperplasia Prostate by Digital Subtraction Angiography

AIM: This work is aimed to describe anatomical features and variants of the prostatic artery (PA) using digital subtraction angiography (DSA). METHODS: This is a descriptive statistic study. We reviewed the DSA of 348 patients, who had a PA embolisation to reduce the benign prostatic hyperplasia (BPH) symptoms at Radiology Department of Bach Mai Hospital from Oct – 2014 to Oct – 2018. RESULTS: PA was found at 660 pelvic halves, of which 30 pelvic halves (4.5%) had two PAs, 630 pelvic halves had one PA. In terms of the origin of PA, in total 690 PAs, the percentage of type 1, 2, 3, 4 and 5 was successively 33.9%, 13.9%, 18.3%, 23.9% and 10.4%, respectively. Atherosclerosis of PA observed in 20.9%. The ‘corkscrew’ pattern was found in 30.4%. The average diameter of PA was 1.5 ± 0.34mm. The anastomosis of PA with surrounding arteries was common. PA may supply rectum (6.1%), seminal vesical (9.6%), bladder (5.2%), contralateral prostatic parenchyma (13.0%), surrounding soft-tissues (3.5%). CONCLUSION: The common trunk with SVA superior vesical artery was the most common origin of PA. Anastomoses of PA with surrounding tissues were complex