Background: Currently, tracking, monitoring insecticide resistance of mosquitoes transmitting disease is an urgent need.\r\n', u'Objectives: To evaluate resistance to insecticide of three mosquito species: Aedes Aegypti, Culex quinquefasciatus and culex tritaenyorhynchus in Ha Noi\r\n', u'Subject and method: Aedes Aegypti, Culex quinquefasciatus culex tritaenyorhynchus mosquito species was collected from some districts of Ha Noi city. These mosquito species was tested sensitivity with 4 insecticides: permethrin 0.75%, lambda-cyhalothrin 0.05%, alpha-cypermethrin 30mg/m2 and DDT 4.0%.\r\n', u'Results: Three main vectors of Dengue fever, Japanese Encephalic and Filariasis mosquitoes were found in a very high density in some areas of Ha Noi City. Aedes aegypti mosquitoes in the districts of Thanh Xuan (TX), Dong Da (DD) and Hoang Mai (HM) was found highly resistant to permethrin, alpha - cypermethrin, lambda - cyhalothrin and DDT with the mortalities rates of 51 % (TX) and 59%(DD); 70%(HM); 90%, 82% and 96%; 74%, 54% and 59%; 1 %, 8% and 32%, respectively. \r\n', u'Culex tritaenyorhynchus was found also highly resistant to permethrin with the mortality rate of 29%, alphacypermethrin - 18%, lambdacyhalothrin - only 3% and DDT x36%. Culex quinquefasciatus was found also highly resistant to those insecticides. \r\n', u'Conclusion: Other insecticides should choose to replace the chemicals used in this experiment to control, kill mosquitoes when epidemics occur.\r\n', u'
Insecticides ; resistance ; Aedes Aegypti ; Culex quinquefasciatus ; culex tritaenyorhynchus

Background:\r\n', u'There are two virus known as Nam Dinh Virus, and Colti group B be found in Viet Nam. These viruses have appeared in the South, the Middle and the Highland. They haven\u2019t been reported in the Southern provinces and Can Thoas well. \r\n', u'Objectives: \r\n', u'To identify the circulation of Nam Dinh virus strain, and coltivirus group B strain in Can Tho, Southern Viet Nam, and their existence in nature.\r\n', u'Subjects and method: \r\n', u'Thirty-four mosquito samples (7, 453 individual mosquitoes) from Culex quinque faciatus and Culex pseudovishnui were collected in Can Tho provice, southern Vietnam 2005.\r\n', u'Isolatingviruses on Aedes albopictuc clone C6/36, Vero cells, and using PT- PCR and ELISA Sandwich for identification. \r\n', u'Results:\r\n', u'2 Nam Dinh virus strains, 2 coltivirus group B strains and 1 flavivirus strain (insect flavivirus) were isolated from Culex quinque faciatus, and no virus was isolated from Culex pseudovishnui.\r\n', u'Conclusion: \r\n', u'The identification of the transmission of Nam dinh Virus, and coltivirus group B in Can Tho province by isolating virus from Culex quinque faciatus has shown the evidence for natural vertical transmission of these viruses.\r\n', u'
Viruses ; Coltivirus ; Flavivirus ; Arboviruses ; Culex ;

OBJECTIVE: This study was aimed at comparing the mandibular arch forms of Korean and Vietnamese patients by using facial axis (FA) points on three-dimensional (3D) models. METHODS: Mandibular casts of 68 Korean (Class I malocclusion, 30; Class II malocclusion, 38) and 78 Vietnamese (Class I malocclusion, 41; Class II malocclusion, 37) patients were scanned in their occluded positions and grouped according to arch form (tapered, ovoid, and square). The FA point of each tooth was digitized on the 3D mandibular models. The measurements and frequency distributions of the arch forms were compared between the ethnic groups. RESULTS: The Vietnamese patients had significantly greater intercanine depth and intercanine and intermolar width-to-depth ratios than the Korean patients (p < 0.05). The frequency distributions of the arch forms were also significantly different (p = 0.038), but no sexual dimorphism was found. CONCLUSIONS: Vietnamese people tend to have deeper and wider arches than Korean people. The three arch forms are evenly distributed in Korean people, but Vietnamese people frequently have square arches. Clinicians should identify the correct arch form of an ethnic group before initiating orthodontic treatment.
Asian Continental Ancestry Group* ; Axis, Cervical Vertebra* ; Ethnic Groups ; Humans ; Malocclusion ; Tooth

A new crinane-type alkaloid, 6-epihydroxypowelline (1), together with six known alkaloids, lycorine (2), 2-O-acetyllycorine (3), deacetylbowdensine (4), 1-epideacetylbowdensine (5), 8-demethyl-3-oxomaritidine (6), and (-)-marithamine (7) were isolated from the whole parts of the Crinum latifolium L. in Vietnam. The structure identification of all compounds was determined by 1D, 2D-NMR as well as HR-ESI-MS spectroscopic techniques. The absolute configuration of these compounds was established by the ECD data. In addition, in vitro inhibition of acetylcholinesterase (AChE) activities was assessed for all isolated alkaloids. All alkaloids had AChE inhibitory effects, with IC50 values ranging from 32.65 ± 2.72 to 212.76 ± 8.30 µM and compound 3 displayed the strongest inhibition of AChE, with IC50 values of 32.65 ± 2.72 µM (in comparison to the reference drug, galanthamine, which had an IC50 of 2.40 ± 0.45 µM).

A new crinane-type alkaloid, 6-epihydroxypowelline (1), together with six known alkaloids, lycorine (2), 2-O-acetyllycorine (3), deacetylbowdensine (4), 1-epideacetylbowdensine (5), 8-demethyl-3-oxomaritidine (6), and (-)-marithamine (7) were isolated from the whole parts of the Crinum latifolium L. in Vietnam. The structure identification of all compounds was determined by 1D, 2D-NMR as well as HR-ESI-MS spectroscopic techniques. The absolute configuration of these compounds was established by the ECD data. In addition, in vitro inhibition of acetylcholinesterase (AChE) activities was assessed for all isolated alkaloids. All alkaloids had AChE inhibitory effects, with IC50 values ranging from 32.65 ± 2.72 to 212.76 ± 8.30 µM and compound 3 displayed the strongest inhibition of AChE, with IC50 values of 32.65 ± 2.72 µM (in comparison to the reference drug, galanthamine, which had an IC50 of 2.40 ± 0.45 µM).

A new crinane-type alkaloid, 6-epihydroxypowelline (1), together with six known alkaloids, lycorine (2), 2-O-acetyllycorine (3), deacetylbowdensine (4), 1-epideacetylbowdensine (5), 8-demethyl-3-oxomaritidine (6), and (-)-marithamine (7) were isolated from the whole parts of the Crinum latifolium L. in Vietnam. The structure identification of all compounds was determined by 1D, 2D-NMR as well as HR-ESI-MS spectroscopic techniques. The absolute configuration of these compounds was established by the ECD data. In addition, in vitro inhibition of acetylcholinesterase (AChE) activities was assessed for all isolated alkaloids. All alkaloids had AChE inhibitory effects, with IC50 values ranging from 32.65 ± 2.72 to 212.76 ± 8.30 µM and compound 3 displayed the strongest inhibition of AChE, with IC50 values of 32.65 ± 2.72 µM (in comparison to the reference drug, galanthamine, which had an IC50 of 2.40 ± 0.45 µM).

A new crinane-type alkaloid, 6-epihydroxypowelline (1), together with six known alkaloids, lycorine (2), 2-O-acetyllycorine (3), deacetylbowdensine (4), 1-epideacetylbowdensine (5), 8-demethyl-3-oxomaritidine (6), and (-)-marithamine (7) were isolated from the whole parts of the Crinum latifolium L. in Vietnam. The structure identification of all compounds was determined by 1D, 2D-NMR as well as HR-ESI-MS spectroscopic techniques. The absolute configuration of these compounds was established by the ECD data. In addition, in vitro inhibition of acetylcholinesterase (AChE) activities was assessed for all isolated alkaloids. All alkaloids had AChE inhibitory effects, with IC50 values ranging from 32.65 ± 2.72 to 212.76 ± 8.30 µM and compound 3 displayed the strongest inhibition of AChE, with IC50 values of 32.65 ± 2.72 µM (in comparison to the reference drug, galanthamine, which had an IC50 of 2.40 ± 0.45 µM).

A new crinane-type alkaloid, 6-epihydroxypowelline (1), together with six known alkaloids, lycorine (2), 2-O-acetyllycorine (3), deacetylbowdensine (4), 1-epideacetylbowdensine (5), 8-demethyl-3-oxomaritidine (6), and (-)-marithamine (7) were isolated from the whole parts of the Crinum latifolium L. in Vietnam. The structure identification of all compounds was determined by 1D, 2D-NMR as well as HR-ESI-MS spectroscopic techniques. The absolute configuration of these compounds was established by the ECD data. In addition, in vitro inhibition of acetylcholinesterase (AChE) activities was assessed for all isolated alkaloids. All alkaloids had AChE inhibitory effects, with IC50 values ranging from 32.65 ± 2.72 to 212.76 ± 8.30 µM and compound 3 displayed the strongest inhibition of AChE, with IC50 values of 32.65 ± 2.72 µM (in comparison to the reference drug, galanthamine, which had an IC50 of 2.40 ± 0.45 µM).

Objective: Human respiratory syncytial virus (RSV) is a primary cause of paediatric severe acute respiratory infection (SARI) worldwide, especially in developing countries. We investigated the genetic characteristics of RSV in northern Viet Nam to determine the prevalence and distribution of subtypes as well as the diversity and transmission patterns of genotypes. Methods: In two facilities, from January 2017 to December 2020, 1563 clinical specimens were collected from paediatric patients hospitalized with SARI and tested for RSV. Selected positive samples underwent sequencing analysis targeting the second hypervariable region of the G gene using next-generation sequencing. Results: The RSV positivity rate was 28.02% (438/1563 samples), and prevalence was highest in children aged <1 year (43.84%; 192/438). Subtype RSV-A accounted for 53.42% (234/438) of cases, RSV-B for 45.89% (201/438), and there was coinfection in 0.68% (3/438). Both subtypes cocirculated and peaked during August–September in each year of the study. Phylogenetic analysis showed that RSV-A samples belonged to the ON1 genotype, which has three subgenotypes: ON1.1, ON1.2 and ON1.3. However, we did not find the 72-nucleotide duplication in the second hypervariable region of the G gene, a characteristic of genotype ON1, in any RSV-A samples. RSV-B samples belonged to genotype BA9. Discussion: Our results provide additional molecular characterization of RSV infections in Viet Nam. Specially, our study is the first to report the absence of the 72-nucleotide duplication in the G gene of RSV-A genotype ON1 in Viet Nam, which may help in understanding the genetic evolution of RSV and be useful for vaccine development in the future.