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1.
Nano Lett ; 24(4): 1145-1152, 2024 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-38194429

RESUMEN

We present a novel technique of genetic transformation of bacterial cells mediated by high frequency electromagnetic energy (HF EME). Plasmid DNA, pGLO (5.4 kb), was successfully transformed into Escherichia coli JM109 cells after exposure to 18 GHz irradiation at a power density between 5.6 and 30 kW m-2 for 180 s at temperatures ranging from 30 to 40 °C. Transformed bacteria were identified by the expression of green fluorescent protein (GFP) using confocal scanning microscopy (CLSM) and flow cytometry (FC). Approximately 90.7% of HF EME treated viable E. coli cells exhibited uptake of the pGLO plasmid. The interaction of plasmid DNA with bacteria leading to transformation was confirmed by using cryogenic transmission electron microscopy (cryo-TEM). HF EME-induced plasmid DNA transformation was shown to be unique, highly efficient, and cost-effective. HF EME-induced genetic transformation is performed under physiologically friendly conditions in contrast to existing techniques that generate higher temperatures, leading to altered cellular integrity. This technique allows safe delivery of genetic material into bacterial cells, thus providing excellent prospects for applications in microbiome therapeutics and synthetic biology.


Asunto(s)
Escherichia coli , Transformación Bacteriana , Plásmidos/genética , ADN/metabolismo , Bacterias/genética , Radiación Electromagnética
3.
Small ; : e2403581, 2024 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-39030883

RESUMEN

This work pioneers to combine fast self-assembly of polyhedral oligomeric silsesquioxanes (POSS) nanocage-based giant surfactants with high etching contrast and directed self-assembly for reliable long-range lateral order to create well-aligned sub-10 nm line nanopatterns via reactive ion etching (RIE). Polystyrene-block-oligo(dimethylsiloxane) substituted POSS (PS-b-oDMS7POSS) with seven oligo(dimethylsiloxane) at the corners of the POSS nanocage and one polystyrene (PS) tail is designed and synthesized as a giant surfactant with self-assembly behaviors like block copolymer (BCP). In contrast to BCP, oDMS7POSS gives a volume-persistent "nanoatom" particle with higher mobility for fast self-assembly and higher segregation strength with PS for smaller feature size. By taking advantage of directed self-assembly using nano-trench fabricated by electron beam lithography, well-ordered nanostructured monolayer with well-aligned parallel oDMS7POSS cylinders can be formed by confined self-assembly within the nano-trench. With the optimization of the RIE treatment using O2 as an etchant, the high etching contrast from the oDMS7POSS and PS gives the formation of well-defined line nanopatterns with sub-10 nm critical dimension that can serve as a mask for pattern transfer in lithography. These results demonstrate a cost-effective approach for nanopatterning by utilizing a creatively designed giant surfactant with sub-10 nm feature size and excellent etching contrast for modern lithographic applications.

4.
Parasitol Res ; 123(5): 209, 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38740597

RESUMEN

Artemisinin (ART) combination therapy is the main treatment for malaria. Pfk13 mutations (or K13 mutations, Kelch 13) are associated with ART resistance. This study aims to conduct a systematic review and meta-analysis of the prevalence of K13 mutations with ART resistance in malaria-endemic countries. An electronic search of studies in 2018 and a manual search in 2020 were performed to identify relevant studies. The risk of bias was assessed using the National Institutes of Health (NIH) quality assessment tool for observational cohort and cross-sectional studies. Data analysis was performed using R 4.1.0. Heterogeneity was estimated using the statistic I2 and Cochran Q test. A total of 170 studies were included in our review. Of these, 55 studies investigated the prevalence of K13 mutations in Southeast Asia. The meta-analysis showed that Southeast Asia had the highest prevalence of K13 mutations, whereas Africa, South America, Oceania, and other Asian countries outside Southeast Asia had a low prevalence of K13 mutations. The C580Y mutation was the most common in Southeast Asia with 35.5% (95%CI: 25.4-46.4%), whereas the dominant mutation in Africa was K189T (22.8%, 95%CI: 7.6-43.2%). This study revealed the emergence of ART resistance associated with K13 mutations in Southeast Asia. The diversity of each type of K13 mutation in other regions was also reported.


Asunto(s)
Antimaláricos , Artemisininas , Polimorfismo Genético , Artemisininas/uso terapéutico , Humanos , Antimaláricos/uso terapéutico , Prevalencia , Resistencia a Medicamentos/genética , Plasmodium falciparum/genética , Plasmodium falciparum/efectos de los fármacos , Malaria/tratamiento farmacológico , Malaria/epidemiología , Malaria Falciparum/tratamiento farmacológico , Malaria Falciparum/epidemiología , Malaria Falciparum/parasitología , Mutación , Proteínas Protozoarias/genética , Asia Sudoriental/epidemiología
5.
Chem Biodivers ; : e202401047, 2024 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-39140429

RESUMEN

The C. luuana Orel & Curry (TD3), C. furfuracea (Merr.) Cohen-Stuard (TD4), C. bidoupensis Truong, Luong & Tran (TD6), C. sinensis (L.) Kuntze (TD7), and C. kissii var. spp (TD8), have been traditionally used as a health-promoting beverage by local people in Ta Dung, Dak Nong. Despite their potential health benefits, further scientific data on biological and phytochemical properties of these plants is needed. To address this issue, this study was conducted to investigate phytochemical and biological properties of five Camellia species extracts, using DPPH, ABTS radical scavenging, copper chelating (Cu-chelator), and tyrosinase inhibition (TI), α-amylase (Al-AI), and α-glucosidase (Al-GI) analyses. As results, ten compounds were identified using UPLC method, in which catechins (mainly EGCG and catechin (Cat)), were the most prevalent, and followed by chlorogenic acid (ChlA), quercitrin (Querci), rutin, and quercetin (Querce). Additionally, multiple factor analysis (MFA) also revealed that TD7, TD3, and TD4 containing high TPC, TFC, high concentrations of EGCG, ChlA, and caffeine were responsible for their high DPPH, ABTS radical scavenging activities, as well asTI, Al-AI and Al-GI. Furthemore, TD6 and TD8, possessing elevated levels of Apig, Querci, Rutin, Querce, Cat, and EA, exhibited a high Cu-chelator property, but a weak enzyme inhibition. From all above-mentioned results, the antioxidative and enzyme inhibitory potentials of Camellia species extracts collected in Dak Nong province in Vietnam were scientifically demonstrated paving a pathway to develop health supplement in further studies.

6.
Chem Biodivers ; 21(9): e202400896, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39140809

RESUMEN

This study investigates Symplocos cochinchinensis (Lour.) S. Moore leaves and stems, commonly known as Symplocos, a plant indigenous to Asia renowned for its traditional use in holistic medicine. A comprehensive phytochemical analysis of S. cochinchinensis led to the isolation of two new lignans, namely symplolignans A and B (1 and 2) along with eleven known lignan glucosides: nortrachelogenin 4-O-ß-D-glucopyranoside (3), nortracheloside (4), matairesinol 4-O-ß-D-glucopyranoside (5), lariciresinol 4'-O-ß-D-glucopyranoside (6), balanophonin 4-O-ß-D-glucopyranoside (7), dehydrodiconiferyl alcohol 4-O-ß-D-glucopyranoside (8), dehydrodiconiferyl alcohol γ'-O-ß-D-glucopyranoside (9), 3-(ß-D-glucopyranosyloxymethyl)-2-(4-hydroxy-3-methoxyphenyl)-5-(3-hydroxypropyl)-7-methoxy-(2R,3S)-dihydrobenzofura (10), and pinoresinol 4'-O-ß-D-glucopyranoside (11). Their chemical structures were elucidated using 1D- and 2D-NMR, mass spectrometry, and their spectroscopic data were compared with those reported in literatures. Furthermore, all compounds were evaluated for their hepatoprotective effects using the Resazurin reduction assay in HepG2 hepatocellular carcinoma cells. Compounds 1, 5, 7, and 8 exhibited notable hepatoprotective efficacy, with cell viability ranging from 105.0±2.6 to 109.2±3.3 at a concentration of 10 µM. This research highlights the therapeutic potential of these compounds and enhanced to the understanding of lignans and neolignans in liver cell proliferation.


Asunto(s)
Glicósidos , Lignanos , Hojas de la Planta , Tallos de la Planta , Lignanos/farmacología , Lignanos/aislamiento & purificación , Lignanos/química , Humanos , Hojas de la Planta/química , Glicósidos/química , Glicósidos/aislamiento & purificación , Glicósidos/farmacología , Tallos de la Planta/química , Células Hep G2 , Supervivencia Celular/efectos de los fármacos , Sustancias Protectoras/farmacología , Sustancias Protectoras/química , Sustancias Protectoras/aislamiento & purificación , Proliferación Celular/efectos de los fármacos , Estructura Molecular , Conformación Molecular
7.
Chem Biodivers ; : e202402584, 2024 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-39440571

RESUMEN

Ten tirucallane triterpenes (1-10) including four undescribed compounds, ailantriphysas A-D (1-4), were isolated from the leaves of Ailanthus triphysa (Dennst.) Alston. Their structures were elucidated by using IR, HR-ESI-MS, 1D- and 2D-NMR spectra. Compound 1 exhibited nitric oxide inhibitory activity with a IC50 value of 8.1 ± µM. Additionally, compound 1 also displayed significant inhibitory effects on the secretion of IL-6 and TNF-α at tested concentrations of 4, 8, and 16 µM.

8.
J Synchrotron Radiat ; 30(Pt 4): 780-787, 2023 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-37338043

RESUMEN

The routes by which foreign objects enter cells is well studied; however, their fate following uptake has not been explored extensively. Following exposure to synchrotron-sourced (SS) terahertz (THz) radiation, reversible membrane permeability has been demonstrated in eukaryotic cells by the uptake of nanospheres; nonetheless, cellular localization of the nanospheres remained unclear. This study utilized silica core-shell gold nanospheres (AuSi NS) of diameter 50 ± 5 nm to investigate the fate of nanospheres inside pheochromocytoma (PC 12) cells following SS THz exposure. Fluorescence microscopy was used to confirm nanosphere internalization following 10 min of SS THz exposure in the range 0.5-20 THz. Transmission electron microscopy followed by scanning transmission electron microscopy energy-dispersive spectroscopic (STEM-EDS) analysis was used to confirm the presence of AuSi NS in the cytoplasm or membrane, as single NS or in clusters (22% and 52%, respectively), with the remainder (26%) sequestered in vacuoles. Cellular uptake of NS in response to SS THz radiation could have suitable applications in a vast number of biomedical applications, regenerative medicine, vaccines, cancer therapy, gene and drug delivery.


Asunto(s)
Neoplasias de las Glándulas Suprarrenales , Nanosferas , Feocromocitoma , Humanos , Radiación Terahertz , Nanosferas/química , Sincrotrones
9.
Neuropediatrics ; 54(1): 68-72, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-35817356

RESUMEN

INTRODUCTION: Various neurologic manifestations have already been described in children during or after severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections. The central nervous system disorders reported in children are mainly encephalopathies during multisystem inflammatory syndrome. We present here an acute meningoencephalitis with cerebral vasculitis associated to a coronavirus disease 2019 (COVID-19) infection in a 13-year-old girl with a 1-year clinical, electroencephalogram (EEG), and magnetic resonance imaging (MRI) follow-up. CASE REPORT: A 13-year-old girl presented acute symptoms of consciousness impairment, frontal headache, hyperthermia, and aphasia, with moderate lymphopenia (900/mm3), elevated C-reactive protein (17 mg/L), cerebrospinal fluid (CSF) pleocytosis (15 cells/mm3), slow background with frontal focalization on EEG, a left frontal ischemic lesion, leptomeningeal enhancement, and bilateral limbic fluid-attenuated inversion recovery hyperintensity on cerebral MRI. Reverse transcription-polymerase chain reaction for SARS-CoV-2 was positive in nasopharyngeal swab and COVID serology was positive for immunoglobulin (Ig) M and G, whereas extensive autoimmune antibody investigation was negative except for a positive low titer of anti-myelin oligodendrocyte glycoprotein in CSF and blood. The diagnosis of probable encephalitis associated to cerebral vasculitis after COVID infection was suggested and steroids pulse were started. She recovered within a few days. Six months later, she had moderate clinical sequels including persistent intermittent headaches, an isolated spatial deficit, and focal spikes on the EEG without argument for epilepsia. CONCLUSION: A teenager without previous medical history presented with acute encephalitis with leptomeningitis and vasculitis after a recent COVID-19 infection. Steroids pulse therapy allowed clinical improvement. Cerebral MRI and EEG helped diagnosis, follow-up of the encephalitis, and evolution after treatment.


Asunto(s)
COVID-19 , Encefalitis , Meningoencefalitis , Vasculitis del Sistema Nervioso Central , Femenino , Humanos , COVID-19/complicaciones , SARS-CoV-2 , Meningoencefalitis/complicaciones , Meningoencefalitis/tratamiento farmacológico , Encefalitis/tratamiento farmacológico , Encefalitis/etiología , Corticoesteroides , Vasculitis del Sistema Nervioso Central/complicaciones , Vasculitis del Sistema Nervioso Central/tratamiento farmacológico
10.
World J Surg Oncol ; 21(1): 140, 2023 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-37147674

RESUMEN

PURPOSE: Total laparoscopic right hemicolectomy with complete mesocolic excision (CME), central vascular ligation (CVL), and D3 lymphadenectomy is still the most challenging colon procedures for gastrointestinal surgeons. We herein report the technical details and our preliminary experience of Bach Mai Procedure - a novel-combining (cranial, medial to lateral, and caudal) approach with early resection of the terminal ileum. METHODS: The dissection stage was central vascular isolation and ligation by a combined multiple approaches in the following four steps: cranial approach, dissecting along the inferior aspect of pancreatic isthmus to reveal the middle colic vessels and the anterior aspect of the superior mesentery vein and then exposed the right gastroepiploic vein and the trunk of Henle; medial-to-lateral approach, exposing the surgical axis - the superior mesenteric vascular axis and then early resection of the terminal ileum to open the dissection from the bottom up; and caudal approach, radical ligation of the ileocecal artery and right colic artery (central vascular ligation), lymph node dissection (D3 lymphadenectomy), and resecting the Toldt fascia of the colon to release the entire right colon from the abdominal wall. RESULTS: In 12 months, there were 32 cases of primary right-sided colon malignancies that have undergone tLRHD3, CME/CVL based on the Bach Mai Procedure. In 3 cases (9.4%), the tumor site was hepatic flexure. The median of lymph node number (LNN) was 38, with the maximum number which was 101. No serious postoperative complications (grade 3 or higher) neither inhospital mortality was detected. CONCLUSION: This Bach Mai procedure, a novel-combining approach with early resection of the terminal ileum, is technically feasible and safe for tLRHD3, CME/CVL. Further investigations and follow-up must be proceeded to evaluate the long-term outcomes of our technique.


Asunto(s)
Neoplasias del Colon , Laparoscopía , Mesocolon , Humanos , Estudios Prospectivos , Neoplasias del Colon/cirugía , Neoplasias del Colon/patología , Escisión del Ganglio Linfático/métodos , Ligadura , Mesocolon/cirugía , Mesocolon/patología , Colectomía/métodos , Laparoscopía/métodos
11.
Chem Biodivers ; 20(6): e202300372, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37145919

RESUMEN

From the fruits of Schisandra cauliflora, five new dimethylbutyrylated dibenzocyclooctadiene lignans, named schisandracaurins A-E, were isolated using separation and chromatographic techniques. Their structures were determined by extensive analyses of HR-ESI-MS, NMR, and ECD spectra. The schisandracaurins A-E potentially inhibited NO production in LPS-activated RAW264.7 cells with their IC50 values from 21.4 to 30.3 µM.


Asunto(s)
Lignanos , Schisandra , Schisandra/química , Lipopolisacáridos/farmacología , Estructura Molecular , Frutas/química , Lignanos/química , Ciclooctanos/farmacología , Ciclooctanos/análisis , Ciclooctanos/química
12.
J Asian Nat Prod Res ; 25(6): 603-609, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36069750

RESUMEN

One new phenylpropanoid glycoside, tinosinen A (1) and 13 known compounds, tinosinen (2), citrusin B (3), picraquassioside C (4), erythro-guaiacylglycerol-ß-O-4'-coniferyl alcohol (5), erythro-guaiacylglycerol-8-O-4'-(sinapyl alcohol) ether (6), erythro-syringylglycerol-8-O-4'-(sinapyl alcohol) ether (7), seco-isolariciresinol 9-O-D-ß-glucopyranoside (8), tinosposide A (9), pinoresinol-4'-O-ß-D-glucopyranoside (10), syringaresinol-4'-O-ß-D-glucopyranoside (11), pinoresinol (12), syringaresinol (13), and lirioresino-ß-dimethyl ether (14) were isolated from the stems of Tinospora sinensis (Lour.) Merr. Their structures were established by detailed spectroscopic studies and comparisons with those reported in the literature. Compound 13 showed significant inhibitory NO production (IC50 value of 38.53 ± 1.90 µM) in RAW264.7 macrophages, LPS-stimulated. Compounds 3-7, 11, 12, and 14 inhibited NO production with IC50 values ranging from 38.53 to 99.07 µM.


Asunto(s)
Tinospora , Tinospora/química , Óxido Nítrico , Éteres
13.
J Asian Nat Prod Res ; 25(1): 18-26, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35306942

RESUMEN

Three new chromanes, malloapeltas J-L (1-3), and one new flavone C-glycoside, malloflavoside (4), together with four known compounds, apigenin 6-C-ß-D-xylopyranosyl-8-C-α-L-arabinopyranoside (5), apigenin 6-C-ß-D-glucopyranosyl-8-C-α-L-arabinopyranoside (6), apigenin 7-O-ß-D-apiofuranosyl-(1→2)-ß-D-glucopyranoside (7), and acantrifoside E (8) were isolated from the methanol extract of the leaves of Mallotus apelta. Their chemical structures were determined using spectroscopic methods, including 1D, 2D NMR, and HR-ESI-MS methods. All the isolated compounds were evaluated their cytotoxic activity against human prostate cancer (PC-3) and human breast cancer (MCF-7) cells, but none of them showed cytotoxicities on both human cancer cell lines.


Asunto(s)
Flavonas , Mallotus (Planta) , Humanos , Apigenina , Glicósidos/farmacología , Glicósidos/química , Flavonas/farmacología
14.
Thorax ; 77(8): 805-811, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35236763

RESUMEN

BACKGROUND: Impaired cough results in airway secretion retention, atelectasis and pneumonia in individuals with Duchenne muscular dystrophy (DMD). Lung volume recruitment (LVR) stacks breaths to inflate the lungs to greater volumes than spontaneous effort. LVR is recommended in DMD clinical care guidelines but is not well studied. We aimed to determine whether twice-daily LVR, compared with standard of care alone, attenuates the decline in FVC at 2 years in boys with DMD. METHODS: In this multicentre, assessor-blinded, randomised controlled trial, boys with DMD, aged 6-16 years with FVC >30% predicted, were randomised to receive conventional treatment or conventional treatment plus manual LVR twice daily for 2 years. The primary outcome was FVC % predicted at 2 years, adjusted for baseline FVC % predicted, age and ambulatory status. Secondary outcomes included change in chest wall distensibility (maximal insufflation capacity minus FVC) and peak cough flow. RESULTS: Sixty-six boys (36 in LVR group, 30 in control) were evaluated (median age (IQR): 11.5 years (9.5-13.5), median baseline FVC (IQR): 85% predicted (73-96)). Adjusted mean difference in FVC between groups at 2 years was 1.9% predicted (95% CI -6.9% to 10.7%; p=0.68) in the direction of treatment benefit. We found no differences in secondary outcomes. CONCLUSION: There was no difference in decline in FVC % predicted with use of twice-daily LVR for boys with DMD and relatively normal lung function. The burden associated with routine LVR may outweigh the benefit. Benefits of LVR to maintain lung health in boys with worse baseline lung function still need to be clarified. TRIAL REGISTRATION NUMBER: NCT01999075.


Asunto(s)
Distrofia Muscular de Duchenne , Tos/etiología , Humanos , Mediciones del Volumen Pulmonar , Masculino , Distrofia Muscular de Duchenne/complicaciones , Distrofia Muscular de Duchenne/tratamiento farmacológico , Pruebas de Función Respiratoria/métodos , Capacidad Vital
15.
Arch Microbiol ; 204(5): 252, 2022 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-35411478

RESUMEN

A widely used herbicide for controlling weeds, glyphosate, is causing environmental pollution. It is necessary to remove it from environment using a cost-effective and eco-friendly method. The aims of this study were to isolate glyphosate-degrading bacteria and to optimize their degradative conditions required for bioremediation. Sixteen bacterial strains were isolated through enrichment and one strain, Rhodococcus soli G41, demonstrated a high removal rate of glyphosate than other strains. Response surface methodology was employed to optimize distinct environmental factors on glyphosate degradation of G41 strain. The optimal conditions for the maximum glyphosate degradation were found to have the NH4Cl concentration of 0.663% and glyphosate concentration of 0.115%, resulting in a maximum degradation of 42.7% after 7 days. Bioremediation analysis showed 47.1% and 40% of glyphosate in unsterile soil and sterile soil was removed by G41 strain after 14 days, respectively. The presence of soxB gene in G41 strain indicates that the glyphosate is degraded via the eco-friendly sarcosine pathway. The results indicated that G41 strain has the potential to serve as an in-situ candidate for bioremediation of glyphosate polluted environments.


Asunto(s)
Herbicidas , Rhodococcus , Biodegradación Ambiental , Glicina/análogos & derivados , Herbicidas/metabolismo , Rhodococcus/genética , Rhodococcus/metabolismo , Suelo , Microbiología del Suelo , Glifosato
16.
BMC Cardiovasc Disord ; 22(1): 520, 2022 12 03.
Artículo en Inglés | MEDLINE | ID: mdl-36460951

RESUMEN

BACKGROUND: Mid-aortic syndrome (MAS) is characterized by the congenital coarctation of the abdominal aorta, abdominal and limb claudication, and hypertension. The etiology of this disorder is very diverse and often manifests in conjunction with Takayasu's arteritis, Williams-Beurens syndrome, and neurofibromatosis. The isolated mid-aortic syndrome is very rare with only a few cases reported in the literature. CASE PRESENTATION: A 45 years old man was admitted to the Emergency Department with sudden muscle weakness and facial paralysis on the left side. Imaging studies reveal right middle cerebral artery infarction at the M1 section. Incidental findings include multiple moderate to severe stenoses in the right internal carotid artery, and total abdominal aorta occlusion. A variant at the ELN gene (Elastin, OMIM*130,160): c.1768G > A/wt (p.Ala590Thr) was identified. CONCLUSION: This is the first reported case of ELN related mid-aortic syndrome in Vietnam which was diagnosed through careful clinical and genetic workup. The finding of mid-aortic syndrome, in this case, was incidental and the decision to reverse the occlusion was postponed as there was no immediate risk of renal failure or reduced blood flow to the lower limb.


Asunto(s)
Coartación Aórtica , Elastina , Masculino , Humanos , Persona de Mediana Edad , Mutación Missense , Síndrome , Aorta Abdominal
17.
Tob Control ; 31(Suppl 2): s88-s94, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-34799436

RESUMEN

BACKGROUND: The government of Vietnam is embarking on a radical tobacco excise tax reform, switching from the current pure ad valorem scheme to a mixed system by adding a specific component. There have been concerns raised by state-owned tobacco companies against this initiative that switching to a mixed scheme may shift consumption away from cheaper, domestic brands to more expensive, foreign brands (produced locally by joint ventures between multinational tobacco companies and domestic firms) and to illicit cigarettes, thus impairing the domestic industry, rather than reducing cigarette consumption effectively. Unfortunately, although this concern has been one of the biggest obstacles to the tobacco tax reform in the country, no study thus far has attempted to address it due mostly to the unavailability of relevant micro-market data with detailed information on brand choice. OBJECTIVES: This research attempts to study cigarette brand substitution patterns and quantify the potential effect of the proposed tax structure change on cigarette brand choice to inform tax policy discussions in Vietnam. METHODS: A discrete choice experiment is conducted to collect data on smokers' stated brand choice when cigarette prices change exogenously. Combined with data on their current cigarette consumption, random parameter logit models were estimated and then used to calculate brand-level price semielasticities as well as numerically simulate the impact of tax reforms on smoking. RESULTS: Smokers are more likely to substitute a low-priced domestic brand with another domestic brand than either with a foreign brand or with an illicit brand, both of which are more expensive. Furthermore, the opt-out is one of the closest substitutes to low-priced brands and also the most sensitive to a change in their prices, implying that smokers of low-priced brands are more likely to buy none of the studied brands when cigarette prices increase. This provides strong suggestive evidence that they appear more likely to stop smoking when faced with higher cigarette prices. Imposing a specific tax tends to reduce the market share for both low-priced and high-priced licit brands, although the estimated market share reduction is larger for the former. In response to specific tax increases, a large share of current smokers do not intend to switch to illegal cigarette brands, but rather choose none of the experimented brands, suggesting their intention to quit. Finally, the magnitude of substitution to illicit brands tends to be negatively related to change in their prices as a result of the specific excise tax hike. CONCLUSION: Contrary to the raised concern, smokers are more likely to substitute a domestic brand with another domestic brand than with a foreign brand. Moreover, the threat of illicit trade should not be exaggerated, and there are actions that the government of Vietnam can take to mitigate the threat effectively.


Asunto(s)
Industria del Tabaco , Productos de Tabaco , Comercio , Recolección de Datos , Humanos , Impuestos , Nicotiana , Vietnam
18.
J Infect Chemother ; 28(10): 1380-1386, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35738340

RESUMEN

INTRODUCTION: To find out risk factors for disease severity and mortality of pediatric COVID-19 in the fourth wave of COVID-19 in Vietnam. METHODS: This retrospective cohort study was performed at Children's Hospital 1 from July to December 2021. All children with COVID-19 confirmed by a positive Realtime RT-PCR SARS-CoV-2 result and treated at COVID-19 department for at least 72 h were included. RESULTS: Of the 850 cases admitting to COVID-19 department, 555 children with COVID-19 confirmed by positive RT-PCR and treated at our center for more than 72 h. Median age of confirmed cases was 22.3 (IQR: 3.2-88.6) months, 55.1% were male, and 84.5% had a history of close contact with confirmed COVID-19 patients. The rate of mild, moderate and severe/critical cases was 73,7%, 9.0% and 17.3%, respectively. One hundred ninety-two children (34.6%) had underlying diseases, in which, neurologic disease was the most common underlying disease (7.9%). Underlying disease, dyspnea, elevated CRP >20 mg/L and elevated ferritin were independent factors related to severe illness. Twenty-point two percent of patients in our study needed respiratory support, including 22 invasive mechanical ventilation cases. Eighteen cases (3.2%) died because of severe comorbidities, poor response to treatment. CONCLUSIONS: In our study, the severe/critical and mortality rates in pediatric COVID-19 cases were relatively high. All fatal cases had severe comorbidities. Underlying disease, dyspnea, and elevated inflammatory markers were independent factors related to severity in pediatric COVID-19 cases.


Asunto(s)
COVID-19 , Pueblo Asiatico , COVID-19/epidemiología , Niño , Preescolar , Disnea , Femenino , Hospitales , Humanos , Lactante , Masculino , Estudios Retrospectivos , Factores de Riesgo , SARS-CoV-2 , Índice de Severidad de la Enfermedad , Vietnam/epidemiología
19.
Health Res Policy Syst ; 20(Suppl 1): 112, 2022 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-36443746

RESUMEN

BACKGROUND: Population ageing and the associated increase in the healthcare needs of older people are putting pressure on the healthcare system in Viet Nam. The country prioritizes healthcare for older people and has developed financial protection policies to mitigate financial hardship due to out-of-pocket health expenditures (OOPHEs) borne by their households. This study examines the level and determinants of the financial burden of OOPHE among households with people aged ≥ 60 years in Viet Nam. METHODS: A cross-sectional household survey was conducted among a sample of 1536 older people living in 1477 households in three provinces representing the North, Central and South regions of Viet Nam during 2019-2020. The financial outcomes were catastrophic health expenditure (CHE), using WHO's definition, and financial distress due to OOPHE. Multivariate binary logistic regression analysis was employed to determine the factors associated with these outcomes. RESULTS: OOPHE for older household members accounted for 86.3% of total household health expenditure. Of households with older people, 8.6% (127) faced CHE, and 12.2% (181) experienced financial distress due to OOPHE. Households were at a higher risk of incurring financial burdens related to health expenditures if they had fewer household members; included only older people; were in rural or remote, mountainous areas; and had older members with noncommunicable diseases. There was no significant association between health insurance coverage and financial burden. However, when older people sought tertiary care or private care, the possibility of a household facing CHE increased. Regardless of the type and level of care, health service utilization by older people results in a higher likelihood of a household encountering financial distress. CONCLUSIONS: This study reveals that OOPHE for older people can impose substantial financial burdens on households, leading them to face CHE and financial distress. This study provides evidence to justify reforming financial protection policies and introducing policy interventions targeted at better protecting older people and their households from the financial consequences of OOPHE. There is also the need to strengthen the grassroots health facilities to provide primary care closer to home at lower costs, particularly for the management of noncommunicable diseases.


Asunto(s)
Estrés Financiero , Enfermedades no Transmisibles , Humanos , Anciano , Estudios Transversales , Vietnam , Instituciones de Salud , Gastos en Salud
20.
Magn Reson Chem ; 60(4): 469-475, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-34877702

RESUMEN

Five new seco-labdane-type diterpenoids, caesalatisics A-E (1-5), were isolated from the leaves of Caesalpinia latisiliqua (Cav.) Hattink. Their chemical structures were determined using 1D and 2D NMR, mass spectra, and circular dichroism spectroscopies.


Asunto(s)
Caesalpinia , Diterpenos , Caesalpinia/química , Diterpenos/análisis , Espectroscopía de Resonancia Magnética , Estructura Molecular , Hojas de la Planta/química
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