Sequence-defined multifunctional polyethers via liquid-phase synthesis with molecular sieving

Synthetic chemists have devoted tremendous effort towards the production of precision synthetic polymers with defined sequences and specific functions. However, the creation of a general technology that enables precise control over monomer sequence, with efficient isolation of the target polymers, is highly challenging. Here, we report a robust strategy for the production of sequence-defined synthetic polymers through a combination of liquid-phase synthesis and selective molecular sieving. The polymer is assembled in solution with real-time monitoring to ensure couplings proceed to completion, on a three-armed star-shaped macromolecule to maximize efficiency during the molecular sieving process. This approach is applied to the construction of sequence-defined polyethers, with side-arms at precisely defined locations that can undergo site-selective modification after polymerization. Using this versatile strategy, we have introduced structural and functional diversity into sequence-defined polyethers, unlocking their potential for real-life applications in nanotechnology, healthcare and information storage

Addressing challenges faced by insecticide spraying for the control of dengue fever in Bangkok, Thailand: a qualitative approach

Background This study focused on evaluating the fumigation scheme and identifying problems encountered during the operation in the Bangkok Metropolitan Administration area. Methods Ten district health officers working in different fumigation teams of the dengue outbreak control programme around Bangkok had participated in an in-depth interview. Five predetermined themes, including (i) dengue surveillance and control strategy, (ii) quality and availability of equipment, (iii) delays, (iv) human resources, and (v) area coverage, and other emerging themes were addressed during the interviews. Results Although the staff seemed to know the operation protocol of the dengue surveillance and control programmes well, they encountered some difficulties in accessing households for proper spraying, and a lack of human and material resources, especially during an outbreak. Other emerging themes concerned inefficient communications among the sectors from hospital to district offices, leading to inaccurate or missing patient addresses for spraying, and the lack of community networks and public cooperation for the dengue control programmes. Conclusions The findings suggest that coordination among the relevant health sectors to acquire accurate and timely information about dengue cases is essential. Involving community networks should help to improve public engagement with and participation in the surveillance and outbreak control programmes.</p

Addressing challenges faced by insecticide spraying for the control of dengue fever in Bangkok, Thailand: a qualitative approach

Background This study focused on evaluating the fumigation scheme and identifying problems encountered during the operation in the Bangkok Metropolitan Administration area. Methods Ten district health officers working in different fumigation teams of the dengue outbreak control programme around Bangkok had participated in an in-depth interview. Five predetermined themes, including (i) dengue surveillance and control strategy, (ii) quality and availability of equipment, (iii) delays, (iv) human resources, and (v) area coverage, and other emerging themes were addressed during the interviews. Results Although the staff seemed to know the operation protocol of the dengue surveillance and control programmes well, they encountered some difficulties in accessing households for proper spraying, and a lack of human and material resources, especially during an outbreak. Other emerging themes concerned inefficient communications among the sectors from hospital to district offices, leading to inaccurate or missing patient addresses for spraying, and the lack of community networks and public cooperation for the dengue control programmes. Conclusions The findings suggest that coordination among the relevant health sectors to acquire accurate and timely information about dengue cases is essential. Involving community networks should help to improve public engagement with and participation in the surveillance and outbreak control programmes.</p

Gallic acid conjugated with gold nanoparticles: antibacterial activity and mechanism of action on foodborne pathogens

Narintorn Rattanata,1 Sompong Klaynongsruang,1 Chanvit Leelayuwat,2 Temduang Limpaiboon,2 Aroonlug Lulitanond,2 Patcharee Boonsiri,3 Sirinart Chio-Srichan,4 Siriwat Soontaranon,4 Supagorn Rugmai,4 Jureerut Daduang2 1Department of Biochemistry, Faculty of Science, 2Centre for Research and Development of Medical Diagnostic Laboratories, Faculty of Associated Medical Sciences, 3Department of Biochemistry, Faculty of Medicine, Khon Kaen University, Khon Kaen, 4Synchrotron Light Research Institute (Public Organization), Nakhon Ratchasima, Thailand Abstract: Foodborne pathogens, including Plesiomonas shigelloides and Shigella flexneri B, are the major cause of diarrheal endemics worldwide. Antibiotic drug resistance is increasing. Therefore, bioactive compounds with antibacterial activity, such as gallic acid (GA), are needed. Gold nanoparticles (AuNPs) are used as drug delivery agents. This study aimed to conjugate and characterize AuNP&ndash;GA and to evaluate the antibacterial activity. AuNP was conjugated with GA, and the core&ndash;shell structures were characterized by small-angle X-ray scattering and transmission electron microscopy. Antibacterial activity of AuNP&ndash;GA against P. shigelloides and S. flexneri B was evaluated by well diffusion method. AuNP&ndash;GA bactericidal mechanism was elucidated by Fourier transform infrared microspectroscopic analysis. The results of small-angle X-ray scattering showed that AuNP&ndash;GA conjugation was successful. Antibacterial activity of GA against both bacteria was improved by conjugation with AuNP because the minimum inhibitory concentration value of AuNP&ndash;GA was significantly decreased (P&lt;0.0001) compared to that of GA. Fourier transform infrared analysis revealed that AuNP&ndash;GA resulted in alterations of lipids, proteins, and nucleic acids at the bacterial cell membrane. Our findings show that AuNP&ndash;GA has potential for further application in biomedical sciences.Keywords: gold nanoparticles, gallic acid, antibacterial activity, foodborne bacteria, small-angle X-ray scattering (SAXS)&nbsp

Synthesis of Sequence-Controlled Copolymers Using Time-Regulated Additions of N -Substituted Maleimides in Styrenic Radical Polymerizations

International audienc

Level of agreement between self-rated and clinician-rated instruments when measuring major depressive disorder in the Thai elderly: a 1-year assessment as part of the THAISAD study

Nahathai Wongpakaran,1 Tinakon Wongpakaran,1 Kamonporn Wannarit,2 Nattha Saisavoey,2 Manee Pinyopornpanish,1 Peeraphon Lueboonthavatchai,3 Nattaporn Apisiridej,4 Thawanrat Srichan,5 Ruk Ruktrakul,5 Sirina Satthapisit,6 Daochompu Nakawiro,7 Thanita Hiranyatheb,7 Anakevich Temboonkiat,8 Namtip Tubtimtong,9 Sukanya Rakkhajeekul,9 Boonsanong Wongtanoi,10 Sitthinant Tanchakvaranont,11 Putipong Bookkamana,12 Usaree Srisutasanavong,1 Raviwan Nivataphand,3 Donruedee Petchsuwan4 1Faculty of Medicine, Chiang Mai University, Chiang Mai, Kingdom of Thailand; 2Faculty of Medicine, Siriraj Hospital, Mahidol University, Bangkok, Kingdom of Thailand; 3Faculty of Medicine, Chulalongkorn University, Bangkok, Kingdom of Thailand; 4Trang Hospital, Trang, Kingdom of Thailand; 5Lampang Hospital, Lampang, Kingdom of Thailand; 6Khon Kaen Hospital, Khon Kaen, Kingdom of Thailand; 7Faculty of Medicine, Ramathibodi Hospital, Mahidol University, Bangkok, Kingdom of Thailand; 8Phramongkutklao Hospital, Bangkok, Kingdom of Thailand; 9Faculty of Medicine Naresuan University, Pitsanulok, Kingdom of Thailand; 10Srisangwal Hospital, Mae Hong Son, Kingdom of Thailand; 11Queen Savang Vadhana Memorial Hospital, Chonburi, Kingdom of Thailand; 12Faculty of Science, Chiang Mai University, Chiang Mai, Kingdom of Thailand Purpose: Whether self-reporting and clinician-rated depression scales correlate well with one another when applied to older adults has not been well studied, particularly among Asian samples. This study aimed to compare the level of agreement among measurements used in assessing major depressive disorder (MDD) among the Thai elderly and the factors associated with the differences found. Patients and methods: This was a prospective, follow-up study of elderly patients diagnosed with MDD and receiving treatment in Thailand. The Mini International Neuropsychiatric Inventory (MINI), 17-item Hamilton Depression Rating Scale (HAMD-17), 30-item Geriatric Depression Scale (GDS-30), 32-item Inventory of Interpersonal Problems scale, Revised Experience of Close Relationships scale, ten-item Perceived Stress Scale (PSS-10), and Multidimensional Scale of Perceived Social Support were used. Follow-up assessments were conducted after 3, 6, 9, and 12 months. Results: Among the 74 patients, the mean age was 68&plusmn;6.02 years, and 86% had MDD. Regarding the level of agreement found between GDS-30 and MINI, Kappa ranged between 0.17 and 0.55, while for Gwet&#39;s AC1 the range was 0.49 to 0.91. The level of agreement was found to be lowest at baseline, and increased during follow-up visits. The correlation between HAMD-17 and GDS-30 scores was 0.17 (P=0.16) at baseline, then 0.36 to 0.41 in later visits (P&lt;0.01). The PSS-10 score was found to be positively correlated with GDS-30 at baseline, and predicted the level of disagreement found between the clinicians and patients when reporting on MDD. Conclusion: The level of agreement between the GDS, MINI, and HAMD was found to be different at baseline when compared to later assessments. Patients who produced a low GDS score were given a high rating by the clinicians. An additional self-reporting tool such as the PSS-10 could, therefore, be used in such under-reporting circumstances. Keywords: late-life depression, measurement, correlatio