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Previous efforts to assemble Rubisco within a cyanobacterial carboxysome-derived protein shell in plant chloroplasts to concentrate CO2 have been unsuccessful. Here, Long et al. produce carboxysomes in tobacco chloroplasts that encapsulate the introduced Rubisco and enable autotrophic growth at elevated CO2.

The ATP-driven bicarbonate transporter 1 (BCT1) from Synechococcus is a four-component complex in the cyanobacterial CO2-concentrating mechanism. BCT1 could enhance photosynthetic CO2 assimilation in plant chloroplasts. However, directing its subunits (CmpA, CmpB, CmpC, and CmpD) to three chloroplast sub-compartments is highly complex. Investigating BCT1 integration into Nicotiana benthamiana chloroplasts revealed promising targeting strategies using transit peptides from the intermembrane space protein Tic22 for correct CmpA targeting, while the transit peptide of the chloroplastic ABCD2 transporter effectively targeted CmpB to the inner envelope membrane. CmpC and CmpD were targeted to the stroma by RecA and recruited to the inner envelope membrane by CmpB. Despite successful targeting, expression of this complex in CO2-dependent Escherichia coli failed to demonstrate bicarbonate uptake. We then used rational design and directed evolution to generate new BCT1 forms that were constitutively active. Several mutants were recovered, including a CmpCD fusion. Selected mutants were further characterized and stably expressed in Arabidopsis thaliana , but the transformed plants did not have higher carbon assimilation rates or decreased CO2 compensation points in mature leaves. While further analysis is required, this directed evolution and heterologous testing approach presents potential for iterative modification and assessment of CO2-concentrating mechanism components to improve plant photosynthesis. [ABSTRACT FROM AUTHOR]

SUMMARY: The introduction of the carboxysome‐based CO2 concentrating mechanism (CCM) into crop plants has been modelled to significantly increase crop yields. This projection serves as motivation for pursuing this strategy to contribute to global food security. The successful implementation of this engineering challenge is reliant upon the transfer of a microcompartment that encapsulates cyanobacterial Rubisco, known as the carboxysome, alongside active bicarbonate transporters. To date, significant progress has been achieved with respect to understanding various aspects of the cyanobacterial CCM, and more recently, different components of the carboxysome have been successfully introduced into plant chloroplasts. In this Perspective piece, we summarise recent findings and offer new research avenues that will accelerate research in this field to ultimately and successfully introduce the carboxysome into crop plants for increased crop yields. Significance Statement: The efficacy of the cyanobacterial CO2‐concentrating mechanism (CCM) relies on its ability to concentrate CO2 around the Rubisco enzyme, which is natively encapsulated within a carboxysome. As our understanding of carboxysome biogenesis and functionality grows, there is optimism that this microcompartment and the cyanobacterial CCM as a whole, can contribute to addressing global food security. [ABSTRACT FROM AUTHOR]

Abstract Few studies have been conducted on group B Streptococcus (GBS) in Vietnam. We determined the GBS colonization and antimicrobial resistance vaginal-rectal profile of 3863 Vietnamese pregnant women over 5 years. Maternal GBS colonization was characterized by antibiotic susceptibility. Overall, the GBS colonization rate was 8.02% (95% CI: 7.20–8.94%). Compared to sampling ≥ 35 weeks of gestation, the GBS colonization rate was statistically higher (p = 0.004) with sampling

Thóc lép ba hoa (Desmodium triflorum) là cây thuốc nam được sử dụng phổ biến và rộng rãi trong y học dân gian. Thử nghiệm in vivo và in vitro của các cao chiết và hoạt chất rutin từ cây thóc lép ba hoa với một số nấm gây bệnh thực vật đã được tiến hành. Các cao chiết từ cây thóc lép ba hoa thể hiện hoạt tính in vitro ức chế nấm Magnaporthe grisea, Sclerotium rolfsii (SR), Fusarium oxysporum và các chủng Colletotrichum sp. ở 1000 µg/mL. Ngoài ra, cao methanol ức chế bệnh đạo ôn do M. grisea gây ra trên cây lúa 50% ở 1000 và 3000 µg/mL in vivo. Sự hiện diện của rutin trong cây được tiến hành bằng phân tách và HPLC. Hoạt tính in vitro của rutin và nanorutin (kích thước hạt 669,3 nm và thế zeta -18,5 mV) được đánh giá với SR và Colletotrichum sp. Cả rutin và nanorutin đều ức chế nấm SR và nanorutin thể hiện hoạt tính tốt hơn khi thử với SR và Colletotrichum gloeosporioides. Các kết quả nghiên cứu đã xác nhận hoạt tính kháng nấm của thóc lép ba hoa và hoạt chất từ...

Trong nghiên cứu này, thành phần hóa học của cao chiết ethyl acetate từ thân và lá cây ba chẽ đã được nghiên cứu. Mẫu nguyên liệu khô được nghiền nhỏ, sau đó chiết bằng phương pháp ngấm kiệt với methanol thu được cao chiết thô. Cao chiết thô được phân tán trong nước và thực hiện quá trình chiết lỏng- lỏng với dung môi ethyl acetate nhằm thu được cao ethyl acetate. Cao chiết ethyl acetate đã được phân tách bằng phương pháp sắc ký trên cột silica gel và Sephadex LH20. Kết quả đã phân lập được bốn hợp chất sạch. Dựa vào dữ liệu phổ 1H-NMR và 13C-NMR và kết hợp với các tài liệu tham khảo đã xác định được cấu trúc của bốn hợp chất hữu cơ đã phân lập là stigmasterol, methyl protocatechuate, methyl syringate và methyl ferulate. Kết quả phân tích HPLC của cao chiết methanol chỉ ra rằng các hợp chất phân cực và kém phân cực là thành phần chính của cao chiết.

Objectives: To assess the modification of the form of medication and evaluate staff observance of good clinical practices Design: One-day assessment of clinical practices. Setting: 17 geriatrics units in the 3 Teaching Hospitals of Paris-Sud (APHP), France. Participants: Elderly in-patients with difficulties swallowing capsules and tablets. Measurements: Assessment of target-patient prescriptions and direct observation of nurses' medical rounds. Results: 155/526 in-patients (29.5%) were unable to swallow tablets or capsules: 98 (40.3%) in long-term care, 46 patients (23.8%) in the rehabilitation unit and 11 (12.2%) in the acute care unit (p = .005). In thirty-nine (27.3%) of the 143 prescriptions studied all tablets were safe to crush and all capsules were safe to open. In 104 cases, at least one medication could not be safely modified, including 26 cases (18.2%) in which none of the prescribed drugs were safe to crush or open. In 48.2% of the 110 medications that were crushed, crushing was forbidden, and presented a potential threat in 12.7% of cases or a reduced efficacy in 8.2% of cases. Crushing methods were rarely appropriate: no specific protective equipment was used (81.8%), crushing equipment was shared between patients without cleaning (95.1%), medications were spilled or lost (69.9%). The method of administration was appropriate (water, jellified water) in 25% of the cases, questionable (soup, coffee, compote, juice, cream) in 55% of the cases and unacceptable (laxative) in 21% of the cases. Conclusion: Management of drug prescriptions in patients with swallowing difficulties is not optimal, and may even have iatrogenic effects. In this study, 12.7% of the modifications of the drug form could have been harmful. Doctors, pharmacists and nurses need to reevaluate their practices. [ABSTRACT FROM AUTHOR]

Growth and productivity in important crop plants is limited by the inefficiencies of the C3 photosynthetic pathway. Introducing CO2-concentrating mechanisms (CCMs) into C3 plants could overcome these limitations and lead to increased yields. Many unicellular microautotrophs, such as cyanobacteria and green algae, possess highly efficient biophysical CCMs that increase CO2 concentrations around the primary carboxylase enzyme, Rubisco, to enhance CO2 assimilation rates. Algal and cyanobacterial CCMs utilize distinct molecular components, but share several functional commonalities. Here we outline the recent progress and current challenges of engineering biophysical CCMs into C3 plants. We review the predicted requirements for a functional biophysical CCM based on current knowledge of cyanobacterial and algal CCMs, the molecular engineering tools and research pipelines required to translate our theoretical knowledge into practice, and the current challenges to achieving these goals. [ABSTRACT FROM AUTHOR]

To satisfy the property requirements for biodegradable medical implants, Zn alloyed with low levels of Mg (≤0.8 wt%) has attracted increased research interest. In the present study, deformation twinning was observed in tensile tests and twinning appears to have an adverse impact on ductility. The profuse twinning in the as-cast Zn-Mg alloys accelerated crack growth in tension due to twinning impingement which caused local stress concentrations and initiates cracking. As-rolled Zn-Mg alloys have better ductility than their as-cast counterparts due to the inhibition of twinning by the refined Mg2Zn11 intermetallic phase and the finer grain size. Keywords: Biodegradable metals, Zn-Mg alloys, Deformation twinning, Mechanical properties, Hot rolling

Emerging from early of 2020, the COVID-19 pandemic has become one of the most serious health crisis globally. In response to such threat, a wide range of digital health applications has been deployed in Vietnam to strengthen surveillance, risk communication, diagnosis, and treatment of COVID-19. Digital health has brought enormous benefits to the fight against COVID-19, however, numerous constrains in digital health application remain. Lack of strong governance of digital health development and deployment; insufficient infrastructure and staff capacity for digital health application are among the main drawbacks. Despite several outstanding problems, digital health is expected to contribute to reducing the spread, improving the effectiveness of pandemic control, and adding to the dramatic transformation of the health system the post-COVID era.

Quantification of plasma cell-free Epstein Barr virus DNA (cf EBV DNA) has been suggested as a promising liquid biopsy assay for screening and early detection of nasopharyngeal carcinoma (NPC). However, the diagnostic value of this assay is currently not known in the population of Vietnam, one of the countries which contributed the most to the NPC cases. Herein, we have reported a highly sensitive quantitative polymerase chain reaction (qPCR)-based assay targeting cf EBV DNA for the detection of NPC. A standard curve with linear regression, R 2 = 0.9961 (range: 25-150 000 copies/mL) and a detection limit of 25 copies/mL were obtained using an EBV standard panel provided by the Chinese University of Hong Kong. The clinical performance of this assay was assessed using plasma samples obtained from 261 Vietnamese individuals. The optimized qPCR assay detected cf EBV DNA in plasma with a sensitivity of 97.4% and a specificity of 98.2%. The absolute quantitative results of pretreatment cf EBV DNA and patient overall clinical stages were statistically correlated ( P < .05). In summary, the remarkably high sensitivity and specificity of our optimized qPCR assay strongly supports the wide use of cf EBV DNA quantification as a routine noninvasive method in early diagnosis and management of patients with NPC.