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Abstract The translation of discoveries on extracellular vesicle (EV) based cancer biomarkers to personalised precision oncology requires the development of robust, sensitive and specific assays that are amenable to adoption in the clinical laboratory. Whilst a variety of elegant approaches for EV liquid biopsy have been developed, most of them remain as research prototypes due to the requirement of a high level of microfabrication and/or sophisticated instruments. Hence, this study is set to develop a simple DNA aptamer‐enabled and fluorescence polarisation‐based homogenous assay that eliminates the need to separate unbound detection ligands from the bound species for EV detection. High specificity is achieved by immobilising EVs with one set of antibodies and subsequently detecting them with a DNA aptamer targeting a distinct EV biomarker. This two‐pronged strategy ensures the removal of most, if not all, non‐EV substances in the input biofluids, including soluble proteins, protein aggregates or non‐vesicular particles, prior to quantifying biomarker‐positive EVs. A limit of detection of 5.0 × 106 EVs/mL was achieved with a linear quantification range of 5.0 × 108 to 2.0 × 1010 EVs/mL. Facilitated by a multiple parametric analysis strategy, this aptamer‐guided fluorescence polarisation assay was capable of distinguishing EVs from three different types of solid cancer cells based on quantitative differences in the levels of the same sets of biomarkers on EVs. Given the simplicity of the method and its ease of implementation in automated clinical biochemistry analysers, this assay could be exploited for future EV‐based continuous and real‐time monitoring of the emergence of new macro‐ or micro‐metastasis, cancer progression as well as the response to treatment throughout different stages of cancer management in the clinic.

Rickettsiae, which are obligate intracellular bacterial parasites, have a life cycle commonly associated with arthropod vectors and animal hosts. Rodents are recognized as their natural reservoir hosts and play a role in transmitting the bacteria to humans through arthropod vectors. The true extent of rickettsial infections in Vietnam remains underestimated due to a limited understanding of the disease’s epidemiology, resulting in a significant public health burden.The aim of this investigation was to assess the prevalence of Rickettsia in wild-living rodents in Dien Bien, Son La, and Phu Tho provinces of Northern Vietnam between 2020 and 2022.Materials and methods. A total of 396 wild-living rodents were collected from the Northern provinces of Vietnam during 2020–2022. Real-time polymerase chain reaction (PCR) was employed to detect the percentage of Rickettsia-positive specimens. Subsequently, the ompB and 17kDa genes were extracted, amplified, and sequenced from the Rickettsia-positive rodents.Results and discussion. Among the 396 rodents examined, the majority were Rattus norvegicus (56.1%), followed by R. tanezumi (37.4%), R. nitidus (2.5%), and R. germaini (1.8%). R. korodentsensis and R. argentiverter constituted the remaining rodents, accounting for 2.2% of the total. The real-time PCR analysis revealed that 27 blood samples out of the 396 rodent samples collected, tested positive for Rickettsia (6.81%). R. germaini was shown to have the highest positive rate 1/8 (12.5%), followed by R. nitidus 1/10 (10.0%), R. tanezumi 14/149 (9.5%), and R. norvegicus 11/222 (4.9%). No other tick-borne pathogens were detected in any of the provinces. Sequencing of the positive samples as regards the ompB and 17kDa genes revealed the closest relation to R. felis. These findings highlight the potentially high risk of R. felis infection in humans and animals within the studied areas.

Conamomum vietnamense is an endemic and rare species from Vietnam. The aim of this study is to determine the chemical compositions, antibacterial and antioxidant properties of the acetone extracts obtained from the different organs of this species for the first time. A total of 82 components were identified from the acetone extracts of leaf, flower, and rhizome of C. vietnamense using Gas chromatography–mass spectrometry (GC/MS) technique. Furthermore, the agar disk-diffusion method was also used to determine the antibacterial activity of the C. vietnamense extracts. Accordingly, the leaf extract was found to be effective against eight out of nine bacterial strains while the flower and rhizome extracts displayed activity against four out of nine tested bacteria. In addition, the three organs of C. vietnamense also possessed the high DPPH scavenging properties. The results of this study indicate that C. vietnamense extracts have the potential to be developed into pharmaceutical products in the future.

This research aims to determine the volatile compounds present in Grewia bulot leaf extracts and evaluate their cytotoxic and antioxidant activities. The volatile constituents of the n-hexane and dichloromethane extracts were identified by using gas chromatography–mass spectrometry. The main compounds identified in the former were neophytadiene (18.2%), methyl palmitate (14.4%), methyl linoleate (9.7%), β-sitosterol (4.5%), and methyl stearate (3.4%), while those in the latter were palmitic acid (9.8%), hexadecane (7.4%), octadecane (6.0%), neophytadiene (5.3%), and 2-tert-butoxyethanol (5.3%). The cytotoxicities of the extracts were examined against four human cancer cell lines (SK-LU-1, Hep-G2, MCF-7, and KB), while their antioxidant activities were assessed using the DPPH radical scavenging assay. The n-hexane and dichloromethane extracts displayed weak activity against these cancer cell lines, with IC50 values ranging from 90.60 ± 3.49 to 98.27 ± 2.77 µg/mL. All extracts showed antioxidant activities, and the methanol extract exhibited the strongest at an SC50 value of 9.39 ± 0.90 µg/mL. This is the first report on the volatile constituents and bioactivities of G. bulot leaf extracts, suggesting their potential application as antioxidants.

Sixth-generation mobile networks (6G) are expected to reach extreme communication capabilities to realize emerging applications demanded by the future society. This paper focuses on six technological directions towards 6G, namely, intent-based networking, THz communication, artificial intelligence, distributed ledger technology/blockchain, smart devices and gadget-free communication, and quantum communication. These technologies will enable 6G to be more capable of catering to the demands of future network services and applications. Each of these technologies is discussed highlighting recent developments, applicability in 6G, and deployment challenges. It is envisaged that this work will facilitate 6G related research and developments, especially along the six technological directions discussed in the paper.

This study is the first to investigate the chemical composition and antioxidant, anti-inflammatory, and cytotoxic activities of Peperomia leptostachya leaf oil. A yellow oil was obtained through hydro-distillation, with a yield of 0.1% (w/w). The GC-MS analysis revealed 66 compounds, constituting 99.6% of the oil. Sesquiterpene hydrocarbons predominated (70.4%), followed by monoterpene hydrocarbons (13.2%), oxygenated sesquiterpenes (12.4%), non-terpenic compounds (2.0%), and oxygenated monoterpenes (1.6%). Major constituents included germacrene D (25.1%), (E)-caryophyllene (17.4%), bicyclogermacrene (6.6%), α-pinene (6.2%), and β-pinene (4.7%). The assessment of antioxidant capacity via 1,1-diphenyl-2-picrylhydrazyl (DPPH) scavenging assay yielded a weak effect, with an IC50 value > 100 µg/mL. The inhibition of lipopolysaccharide-induced nitric oxide production in RAW 264.7 cells was quantified using the MTT assay, showing an IC50 value of 15.15 ± 0.68 µg/mL. Furthermore, cytotoxic effects on SK-LU-1 cell line growth were evaluated using the sulforhodamine B assay, resulting in an IC50 value of 37.45 ± 2.43 μg/mL. The anti-inflammatory activity was notable among the analyzed bioactivities of this oil. By employing a computational model, the predominant secondary metabolites in the essential oil were selected as candidates for interaction analysis with cyclooxygenase-2, an enzyme implicated in the inflammatory response. Our findings suggest that P. leptostachya leaf oil could serve as a potential source of natural compounds with prospective therapeutic effects in treating inflammatory conditions.

Abstract Background Vietnam’s aging population is growing rapidly, but its health workforce’s capacity to provide quality geriatric care is not clearly understood. We aimed to provide a cross-culturally relevant and validated instrument to assess evidence-based geriatric knowledge among healthcare providers in Vietnam. Methods We translated the Knowledge about Older Patients Quiz from English to Vietnamese using cross-cultural adaptation methods. We validated the translated version by evaluating its relevance to the Vietnamese context, as well as its semantic and technical equivalence. We fielded the translated instrument on a pilot sample of healthcare providers in Hanoi, Vietnam. Results The Vietnamese Knowledge about Older Patients Quiz (VKOP-Q) had excellent content validity (S-CVI/Ave) and translation equivalence (TS-CVI/Ave) of 0.94 and 0.92, respectively. The average VKOP-Q score was 54.2% (95% CI: 52.5—55.8) and ranged from 33.3 to 73.3% among 110 healthcare providers in the pilot study. Healthcare providers in the pilot study had low scores on questions related to the physiopathology of geriatric conditions, communication techniques with sensory impaired older adults, and differentiating age related changes from abnormal changes or symptoms. Conclusions The VKOP-Q is a validated instrument to assess geriatric knowledge among healthcare providers in Vietnam. The level of geriatric knowledge among healthcare providers in the pilot study was unsatisfactory, which supports the need for further assessment of geriatric knowledge among a nationally representative sample of healthcare providers.

This study investigated the chemical components and bioactivities of acetone leaf extracts of nine Annonaceae plants collected in the Binh Chau-Phuoc Buu Nature Reserve, Vietnam. A total of 182 constituents were identified, with linolenic acid, diaeudesmin, germacrene D, 1-octadecenoic acid, 8-(3-octyl-2-oxiranyl)-1-octanol, oleic acid, and phenylmethyl ester being the major compounds. The antimicrobial activity of the extracts was evaluated using a disc diffusion assay. Eight of the nine extracts, except for the Mitrephora thorelii extract, showed an inhibition effect against Bacillus cereus and Staphylococcus aureus. The antioxidant activity of the extracts was determined using DPPH assay, and the cytotoxic activity was deter mined using SRB assay. The results showed that the acetone extracts of Artabotrys hexapetalus, Uvularia grandiflora, Polyalthia luensis, Xylopia pierrei, Sphaerocoryne affinis, Desmos cochinchinensis, Uvaria littoralis, Mitrephora thorelii, and Goniothalamus touranensis had significant activity with IC50 for the DPPH radical scavenging activity ranging from 18.56 to 702.33 μg/mL, and the IC50 for the cytotoxic effects ranged from 5.39 to 251.77 μg/mL. Overall, the results obtained provide experimental evidence for the potential use of these plants in medicine and other related fields.

Abstract Background People are living longer, and the majority of aging people reside in low- and middle-income countries (LMICs). However, inappropriate healthcare contributes to health disparities between populations of aging people and leads to care dependency and social isolation. Tools to assess and evaluate the effectiveness of quality improvement interventions for geriatric care in LMICs are limited. The aim of this study was to provide a validated and culturally relevant instrument to assess patient-centered care in Vietnam, where the population of aging people is growing rapidly. Methods The Patient-Centered Care (PCC) measure was translated from English to Vietnamese using forward-backward method. The PCC measure grouped activities into sub-domains of holistic, collaborative, and responsive care. A bilingual expert panel rated the cross-cultural relevance and translation equivalence of the instrument. We calculated Content Validity Indexing (CVI) scores at both the item (I-CVI) and scale (S-CVI/Ave) levels to evaluate the relevance of the Vietnamese PCC (VPCC) measure to geriatric care in the Vietnamese context. We piloted the translated instrument VPCC measure with 112 healthcare providers in Hanoi, Vietnam. Multiple logistic regression models were specified to test the a priori null hypothesis that geriatric knowledge is not different among healthcare providers with perception of high implementation compared with low implementation of PCC measures. Results On the item level, all 20 questions had excellent validity ratings. The VPCC had excellent content validity (S-CVI/Ave of 0.96) and translation equivalence (TS- CVI/Ave of 0.94). In the pilot study, the highest-rated PCC elements were the holistic provision of information and collaborative care, while the lowest-rated elements were the holistic attendance to patients’ needs and responsive care. Attention to the psychosocial needs of aging people and poor coordination of care within and beyond the health system were the lowest-rated PCC activities. After controlling for healthcare provider characteristics, the odds of the perception of high implementation of collaborative care were increased by 21% for each increase in geriatric knowledge score. We fail to reject the null hypotheses for holistic care, responsive care and PCC. Conclusion The VPCC is a validated instrument that may be utilized to systemically evaluate the practice of patient-centered geriatric care in Vietnam.