Sleep Quality and Poor Sleep-related Factors Among Healthcare Workers During the COVID-19 Pandemic in Vietnam

Thang Phan,Ha Phan Ai Nguyen,Cao Khoa Dang,Minh Tri Phan,Vu Thanh Nguyen,Van Tuan Le,Binh Thang Tran,Chinh Van Dang,Tinh Huu Ho,Minh Tu Nguyen,Thang Van Dinh,Van Trong Phan,Binh Thai Dang,Huynh Ho Ngo The Korean Society for Preventive Medicine 2023 예방의학회지 Vol.56 No.4

Objectives: The coronavirus disease 2019 (COVID-19) pandemic has increased the workload of healthcare workers (HCWs), impacting their health. This study aimed to assess sleep quality using the Pittsburgh Sleep Quality Index (PSQI) and identify factors associated with poor sleep among HCWs in Vietnam during the COVID-19 pandemic. Methods: In this cross-sectional study, 1000 frontline HCWs were recruited from various healthcare facilities in Vietnam between October 2021 and November 2021. Data were collected using a 3-part self-administered questionnaire, which covered demographics, sleep quality, and factors related to poor sleep. Poor sleep quality was defined as a total PSQI score of 5 or higher. Results: Participants' mean age was 33.20±6.81 years (range, 20.0-61.0), and 63.0% were women. The median work experience was 8.54±6.30 years. Approximately 6.3% had chronic comorbidities, such as hypertension and diabetes mellitus. About 59.5% were directly responsible for patient care and treatment, while 7.1% worked in tracing and sampling. A total of 73.8% reported poor sleep quality. Multivariate logistic regression revealed significant associations between poor sleep quality and the presence of chronic comorbidities (odds ratio [OR], 2.34; 95% confidence interval [CI], 1.17 to 5.24), being a frontline HCW directly involved in patient care and treatment (OR, 1.59; 95% CI, 1.16 to 2.16), increased working hours (OR, 1.84; 95% CI,1.37 to 2.48), and a higher frequency of encountering critically ill and dying patients (OR, 1.42; 95% CI, 1.03 to 1.95). Conclusions: The high prevalence of poor sleep among HCWs in Vietnam during the COVID-19 pandemic was similar to that in other countries. Working conditions should be adjusted to improve sleep quality among this population.

Drug resistance and the genotypic characteristics of rpoB and katG in rifampicin- and/or isoniazid-resistant Mycobacterium tuberculosis isolates in central Vietnam

Thi Binh Nguyen Nguyen,Thi Kieu Diem Nguyen,Van Hue Trương,Thi Tuyet Ngoc Tran,van Bao Thang Phan,Thi Tuyen Nguyen,Hoang Bach Nguyen,Viet Quynh Tram Ngo,Van Tuan Mai,Paola Molicotti 질병관리본부 2023 Osong Public Health and Research Persptectives Vol.14 No.5

Objectives: Tuberculosis (TB) and drug-resistant TB (DR-TB) are national health burdens in Vietnam. In this study, we investigated the prevalence of rifampicin (RIF) and/or isoniazid (isonicotinic acid hydrazide, INH) resistance in patients with suspected TB, and applied appropriate techniques to help rapidly target DR-TB. Methods: In total, 1,547 clinical specimens were collected and cultured using the BACTEC MGIT system (Becton Dickinson and Co.). A resazurin microtiter assay (REMA) was used to determine the proportions of RIF and/or INH resistance. A real-time polymerase chain reaction panel with TaqMan probes was employed to identify the mutations of rpoB and katG associated with DR-TB in clinical isolates. Genotyping of the identified mutations was also performed. Results: A total of 468 Mycobacterium tuberculosis isolates were identified using the REMA. Of these isolates, 106 (22.6%) were found to be resistant to 1 or both antibiotics. Of the resistant isolates, 74 isolates (69.8%) were resistant to isoniazid (INH) only, while 1 isolate (0.94%) was resistant to RIF only. Notably, 31 isolates (29.24%) were resistant to both antibiotics. Of the 41 phenotypically INH-resistant isolates, 19 (46.3%) had the Ser315Thr mutation. There were 8 different rpoB mutations in 22 (68.8%) of the RIF-resistant isolates. The most frequently detected mutations were at codons 531 (37.5%), 526 (18.8%), and 516 (6.3%). Conclusion: To help prevent new cases of DR-TB in Vietnam, it is crucial to gain a comprehensive understanding of the genotypic DR-TB isolates.

Mental Health Among Healthcare Workers During the COVID-19 Pandemic in Vietnam

Nhan Phuc Thanh Nguyen,Ha Phan Ai Nguyen,Cao Khoa Dang,Minh Tri Phan,Huynh Ho Ngoc Quynh,Van Tuan Le,Chinh Van Dang,Tinh Huu Ho,Van Trong Phan,Van Trong Phan,Thang Phan,Dang Thi Anh Thu 대한예방의학회 2024 예방의학회지 Vol.57 No.1

Objectives: The objective of this study was to characterize mental health issues among Vietnamese healthcare workers (HCWs) and to identify related factors.Methods: A cross-sectional study was conducted with 990 HCWs in 2021. Their mental health status was measured using the Depression, Anxiety, and Stress Scale.Results: In total, 49.9%, 52.3%, and 29.8% of respondents were found to have depression, anxiety, and stress, respectively. The multivariable linear regression model revealed that factors associated with increased anxiety scores included depression scores (β, 0.45; 95% confidence interval [CI], 0.39 to 0.51) and stress scores (β, 0.46; 95% CI, 0.41 to 0.52). Factors associated with increased depression scores included being frontline HCWs (β, 0.57; 95% CI, 0.10 to 1.10), stress scores (β, 0.50; 95% CI, 0.45 to 0.56), and anxiety scores (β, 0.41; 95% CI, 0.36 to 0.47), while working experience was associated with reduced depression scores (β, -0.08; 95% CI, -0.16 to -0.01). Factors associated with increased stress scores included working experience (β, 0.08; 95% CI, 0.00 to 0.16), personal protective equipment interference with daily activities (β, 0.55; 95% CI, 0.07 to 1.00), depression scores (β, 0.54; 95% CI, 0.48 to 0.59), and anxiety scores (β, 0.45; 95% CI, 0.39 to 0.50), while age was associated with reduced stress scores (β, -0.12; 95% CI, -0.20 to -0.05).Conclusions: Specific interventions are necessary to enhance and promote the mental health of HCWs so they can successfully cope with the circumstances of the pandemic.

Lanostane Triterpenoids from Ganoderma tropicum Collected in Vietnam and Their Nitroblue Tetrazolium Reductive Activity In Vitro

Nguyen Thi Duyen,Nguyen Minh Khoi,Phan Nguyen Truong Thang,Duong Minh Tan,Tran Viet Hung,Do Thi Ha 한국생약학회 2020 Natural Product Sciences Vol.26 No.4

A new compound, 3β-acetoxylanosta-7,9(11),24-triene-26-al (3), and seven known compounds (1 – 2 and 4 – 8) were isolated from Ganoderma tropicum (Jung.) Bres. collected in Tay Nguyen, Vietnam. The structures of these compounds were determined by one- and two-dimensional nuclear magnetic resonance spectroscopy, electrospray ionization mass spectrometry (ESI-MS), and high-resolution ESI-MS, and by comparison with literature data. All of the isolated compounds were tested for nitroblue tetrazolium (NBT) reduction activity in Saccharomyces cerevisiae-stimulated RAW 246.7 cells. Among them, compounds 2 – 4 and 6 – 8 enhanced the NBT reduction in a dose-dependent manner.

Transition Metal Disulfide Nanosheets Synthesized by Facile Sonication Method for the Hydrogen Evolution Reaction

Nguyen, Thang Phan,Choi, Seokhoon,Jeon, Jong-Myeong,Kwon, Ki Chang,Jang, Ho Won,Kim, Soo Young American Chemical Society 2016 The Journal of Physical Chemistry Part C Vol.120 No.7

<P>Two-dimensional transition metal disulfide (TMD) nanosheets, including MoS2, WS2, TaS2, and TiS2, were used to catalyze the hydrogen evolution reaction (HER). The TMDs were exfoliated by sonication to generate nanosheet layers that were approximately a few hundred milometers in size. X-ray diffraction and transmission electron microscope data indicated that the major plane of the exfoliated nanosheets was the (002) plane and that the hexagonal structure is maintained after exfoliation with lattice constants of 0.32 nm for MoS2 and WS2 and 0.34 nm for TaS2 and TiS2. Exfoliated MoS2, WS2, TaS2, and TiS2 loaded on Au electrodes exhibited good electrocatalytic activity with low onset potentials of similar to 100, 150, 175, and 135 mV, respectively, at a current density of -1 mA/cm(2). MoS2 and TiS2 exhibited the best HER performance with Tafel slopes of 94.91 and 91 mV/decade. These results indicated that TMD nanosheets have potential applications as HER catalysts for the mass production of hydrogen.</P>

Size-Dependent Properties of Two-Dimensional MoS₂ and WS₂

Nguyen, Thang Phan,Sohn, Woonbae,Oh, Jeong Hyeon,Jang, Ho Won,Kim, Soo Young American Chemical Society 2016 The Journal of Physical Chemistry Part C Vol.120 No.18

<P>The characteristic differences between MoS2 and WS2 nanosheets and nanodots are investigated. The nanosheets were formed by liquid-phase sonication, while the nanodots were formed by breaking the nanosheets through heating the solvent ethylene glycol. The nanosheets and nanodots were approximately 0.7-2 nm thick, with slight deviation. Most of the nanosheets were longer than 100 nm, and most of the nanodots were shorter than 5 nm. As the bulk materials were transformed into nanosheets and/or nanodots, the absorption peaks and Raman peaks shifted to shorter wavelengths. Photoluminescence peaks were observed at 500 and 445 nm in the MoS2 and WS2 samples smaller than 100 nm. In the X-ray diffraction spectra, only the (002) peak was present in the nanosheets, while no peak was detected for the nanodots due to their small size. No detectable differences between the nanosheets Wavelength (nm) and nanodots were observed in the transmission electron micrographs, synchrotron radiation photoemission spectra, or work function measurements, suggesting that exfoliation did not affect the crystal structure or bonding configuration of MoS2 and WS2. These results could potentially be used for the application of MoS2 and WS2 nanosheets and nanodots in optical devices, hydrogen evolution reaction catalysts, bioapplicable devices, and so on.</P>

The synthesis and applications of transition metal dichalcogenide using liquid exfoliation method

THANG NGUYEN PHAN,김수영 한국고분자학회 2016 한국고분자학회 학술대회 연구논문 초록집 Vol.41 No.1

Surface extension of MeS₂ (Me=Mo or W) nanosheets by embedding MeS_x for hydrogen evolution reaction

Nguyen, Thang Phan,Le, Quyet Van,Choi, Seokhoon,Lee, Tae Hyung,Hong, Seung-Pyo,Choi, Kyoung Soon,Jang, Ho Won,Lee, Min Hyung,Park, Tae Jung,Kim, Soo Young Elsevier 2018 ELECTROCHIMICA ACTA Vol.292 No.-

<P><B>Abstract</B></P> <P>Two-dimensional transition metal dichalcogenides (2D-TMDs), such as MoS<SUB>2</SUB> and WS<SUB>2</SUB> nanosheets (MeS<SUB>2</SUB>-NS), are reported as efficient catalysts for hydrogen evolution reaction (HER), which can potentially replace the expensive platinum catalyst. In this report, 1T phase MeS<SUB>2</SUB> (1T-MeS<SUB>2</SUB>) NS are synthesized by lithium-intercalation exfoliation method, subsequently being modified by amorphous MoS<SUB>x</SUB> and WS<SUB>x</SUB> (MeS<SUB>x</SUB>@MeS<SUB>2</SUB>-NS) through a solvothermal method. Interestingly, MeS<SUB>x</SUB>@MeS<SUB>2</SUB>-NS significantly improves the HER performance compared with bare MeS<SUB>2</SUB>-NS as catalysts. Among these, MoS<SUB>x</SUB>@MoS<SUB>2</SUB> is observed to be the best combination for HER, with an onset potential and Tafel slope of 114 mV and 45.1 mV decade<SUP>−1</SUP>, respectively. The enhancement in the HER device using MeS<SUB>x</SUB>@MeS<SUB>2</SUB>-NS as the catalyst originates from vertically grown MeS<SUB>x</SUB>, which provides additional active sulfur sites for the reaction, while inhibiting the restacking of MeS<SUB>2</SUB>-NS. Furthermore, MoS<SUB>x</SUB>@MoS<SUB>2</SUB>-NS shows stable catalytic properties for HER after the 1000 cyclic test, without any observable changes. Thus, this study presents a facile method for the synthesis of 2D-TMD catalyst for HER towards large-scale and long-term stability for practical application.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Self-template growth of a 2D materials for hierarchical structure. </LI> <LI> Facile and scalable hydrothermal method. </LI> <LI> Improving of current density and the Tafel slope in optimized samples. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Inhomogeneous Ferromagnetism and Spin-Glass-Like Behavior in <inline-formula> <tex-math notation='TeX'> <tex> $({\rm Nd}_{1-x}{\rm Y}_{x})_{0.7}{\rm Sr}_{0.3}{\rm MnO}_{3}$ </tex> </tex-math></inline-formula> With <inline-formula> <tex-math notation='TeX

Phan, T. L.,Nguyen, V. D.,Ho, T. A.,Khiem, N. V.,Thanh, T. D.,Phuc, N. X.,Thang, P. D.,Yu, S. C. IEEE 2014 IEEE transactions on magnetics Vol.50 No.6

<P>The magnetic properties of polycrystalline ceramic samples (Nd1-xYx)(0.7)Sr0.3MnO3 with x = 0.21 - 0.35 were studied by means of dc magnetization and ac susceptibility measurements. Experimental results reveal a strong decrease of the ferromagnetic (FM)-paramagnetic phase-transition temperature (T-C) from 97 to 65 K as increasing x from 0.21 to 0.35, respectively. There is magnetic inhomogeneity associated with short-range FM order. Particularly, the samples undergo a spin-glass (SG) phase transition at the so-called blocking temperature (T-B) below T-C, which shifts toward lower temperatures with increasing the applied field, Hex; T-B -> T-g (the SG phase-transition temperature) as H-ex -> 0. The existence of the SG behavior in these samples was also confirmed by frequency (f) dependences of the ac susceptibility. For the in-phase/real component, chi' (T), it shows a frequency-dependent peak at the SG freezing temperature (T-f); T-f -> T-g as f -> 0. Dynamics of this process were analyzed by means of the slowing down scaling law, tau/tau(0) proportional to (T-f/T-g - 1)(-zv), where tau(0) and zv are the characteristic time and critical exponent, respectively. Fitting the experimental T-f(f) data to the scaling law gave the results of zv = 10.1-12.3 and tau(0) = 10(-21)-10(-15)s. These values are different from those expected for canonical SG systems with zv = 10 and tau(0) = 10(-13)s, revealing the cluster-SG behavior of (Nd1-xYx)(0.7)Sr0.3MnO3 samples. Notably, the increase in Y content leads to the shift of tau(0) and zv values toward those of canonical SG systems, which is ascribed to an expansion of SG clusters.</P>

Synthesis of fluorescent silicon quantum dots for ultra-rapid and selective sensing of Cr(VI) ion and biomonitoring of cancer cells

Phan, Le Minh Tu,Baek, Seung Hoon,Nguyen, Thang Phan,Park, Kyoung Yeol,Ha, Siyoung,Rafique, Rafia,Kailasa, Suresh Kumar,Park, Tae Jung Elsevier 2018 Materials science & engineering. C, Materials for Vol.93 No.-

<P><B>Abstract</B></P> <P>A facile one-step synthetic approach was developed for fabrication of fluorescent silicon quantum dots (Si QDs) and used as a probe for fluorescence detection of hexavalent chromium (Cr (VI)) in environmental water samples. The as-prepared Si QDs exhibit a strong fluorescence emission peak at 520 nm with a quantum yield of 14.2%. The fluorescent Si QDs were rapidly produced by using ascorbic acid as a reductant at 55 °C. The emission peak of Si QDs at 420 nm was effectively quenched upon the addition of Cr(VI). The Si QDs acted as the best fluorescent probe for the detection of Cr(VI) at PBS pH 7.4. The developed probe possessed a good linear correlation (R<SUP>2</SUP> = 0.992) between Cr(VI) concentration (1.25–40 μM) and the (F<SUB>0</SUB>-F)/F<SUB>0</SUB> values with a detection limit of 0.65 μM. Furthermore, the Si QDs served as a bio-probe for fluorescence imaging of A549 lung cancer cells and cell viability results confirmed the good biocompatible nature of Si QDs. The as-fabricated Si QDs show several advantages such as rapidity, selectivity and biocompatibility for sensing of Cr(VI) and imaging of A549 cells, which opens a facile analytical platform for environmental and bioimaging applications.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Facile one-step hydrothermal method for synthesis of fluorescent Si QDs </LI> <LI> A rapid probe was developed for analysis of Cr(VI) without any sample preparations. </LI> <LI> The detection limit of Cr(VI) was estimated to be 0.65 μM. </LI> <LI> The method exhibited good selectivity and sensitivity for assay of Cr(VI). </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>