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1.
Radiol Case Rep ; 19(7): 2629-2632, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38645949

ABSTRACT

Ruptured aneurysmal subarachnoid hemorrhage associated with multiple basilar trunk aneurysms represents a rare clinical condition. Endovascular intervention stands as the preferred therapeutic approach. We present the case of a 35-year-old patient with subarachnoid hemorrhage and three consecutive basilar trunk aneurysms. Utilizing a flow-diverter stent, we achieved simultaneous occlusion of all 3 aneurysms, performed 2 hours post dual antiplatelet therapy (comprising salicylic acid 300 mg and ticagrelor 180 mg). Sustained resistance to clopidogrel necessitated the subsequent 3 months, followed by single antiplatelet therapy. At the 1-month follow-up, the patient demonstrated a favorable clinical course, devoid of cerebral infarction, and evidenced unobstructed stent patency upon brain magnetic resonance imaging.

2.
PLoS One ; 17(11): e0275149, 2022.
Article in English | MEDLINE | ID: mdl-36417456

ABSTRACT

Peatlands account for 15 to 30% of the world's soil carbon (C) stock and are important controls over global nitrogen (N) cycles. However, C and N concentrations are known to vary among peatlands contributing to the uncertainty of global C inventories, but there are few global studies that relate peatland classification to peat chemistry. We analyzed 436 peat cores sampled in 24 countries across six continents and measured C, N, and organic matter (OM) content at three depths down to 70 cm. Sites were distinguished between northern (387) and tropical (49) peatlands and assigned to one of six distinct broadly recognized peatland categories that vary primarily along a pH gradient. Peat C and N concentrations, OM content, and C:N ratios differed significantly among peatland categories, but few differences in chemistry with depth were found within each category. Across all peatlands C and N concentrations in the 10-20 cm layer, were 440 ± 85.1 g kg-1 and 13.9 ± 7.4 g kg-1, with an average C:N ratio of 30.1 ± 20.8. Among peatland categories, median C concentrations were highest in bogs, poor fens and tropical swamps (446-532 g kg-1) and lowest in intermediate and extremely rich fens (375-414 g kg-1). The C:OM ratio in peat was similar across most peatland categories, except in deeper samples from ombrotrophic tropical peat swamps that were higher than other peatlands categories. Peat N concentrations and C:N ratios varied approximately two-fold among peatland categories and N concentrations tended to be higher (and C:N lower) in intermediate fens compared with other peatland types. This study reports on a unique data set and demonstrates that differences in peat C and OM concentrations among broadly classified peatland categories are predictable, which can aid future studies that use land cover assessments to refine global peatland C and N stocks.


Subject(s)
Carbon , Soil , Carbon/chemistry , Soil/chemistry , Wetlands , Nitrogen
3.
Braz J Biol ; 84: e264369, 2022.
Article in English | MEDLINE | ID: mdl-36287528

ABSTRACT

Panax vietnamensis Ha et Grushv. is a precious medicinal species native to the tropical forests of Vietnam. Due to habitat loss and over-harvesting, this species is endangered in Vietnam. To conserve the species, we investigated genetic variability and population structure using nine microsatellites for 148 individuals from seven populations across the current distribution range of P. vietnamensis in Vietnam. We determined a moderate genetic diversity within populations (HO = 0.367, HE = 0.437) and relatively low population differentiation (the Weir and Cockerham index of 0.172 and the Hedrick index of 0.254) and showed significant differentiation (P < 0.05), which suggested fragmented habitats, over-utilization and over-harvesting of P. vietnamensis. Different clustering methods revealed that individuals were grouped into two major clusters, which were associated with gene flow across the geographical range of P. vietnamensis. This study also detected that ginseng populations can have undergone a recent bottleneck. We recommend measures in future P. vietnamensis conservation and breeding programs.


Subject(s)
Panax , Humans , Panax/genetics , Panax/chemistry , Vietnam , Plant Breeding , Microsatellite Repeats/genetics , Asian People , Genetic Variation/genetics
4.
Nat Prod Res ; 35(4): 548-555, 2021 Feb.
Article in English | MEDLINE | ID: mdl-30887834

ABSTRACT

New asterosaponin, acanthaglycoside G (1), along with three previously known steroidal oligoglycosides (2‒4), were isolated from the ethanolic extract of the starfish Acanthaster planci, collected off the coast of Vietnam. The structure of 1 was mainly elucidated by extensive NMR and ESIMS techniques as sodium 6-O-{ß-D-fucopyranosyl-(1→2)-ß-D-quinovopyranosyl-(1→4)-[ß-D-quinovopyranosyl-(1→2)]-ß-D-quinovopyranosyl-(1→3)-ß-D-quinovopyranosyl}-6α-hydroxy-5α-pregn-9(11)-en-20-one-3ß-yl sulfate. Compounds 3 and 4 showed slight cytotoxic activities against cancer RPMI-7951, HT-29, and MDA-MB-231 cell lines, but effectively inhibited in non-toxic concentrations colony formation of HT-29 and MDA-MB-231 cells and cell migration of MDA-MB-231 cells. Compounds 1 and 2 were inactive or less active, respectively.


Subject(s)
Saponins/isolation & purification , Saponins/pharmacology , Starfish/chemistry , Tropical Climate , Animals , Antineoplastic Agents/chemistry , Antineoplastic Agents/pharmacology , Cell Death/drug effects , Cell Line, Tumor , Cell Movement/drug effects , Humans , Proton Magnetic Resonance Spectroscopy , Saponins/chemistry , Vietnam
5.
Glob Health Sci Pract ; 8(4): 680-688, 2020 12 23.
Article in English | MEDLINE | ID: mdl-33361235

ABSTRACT

INTRODUCTION: Limited information exists on health care workers' (HCWs) perceptions about use of multidose vaccine vials and their preferences about doses per container (DPC). We present findings from qualitative studies conducted in Senegal, Vietnam, and Zambia to explore HCWs' behavior regarding opening vials and their perceptions and preferences for the number of doses in vials of BCG and measles-containing vaccine (MCV). Zambia and Senegal currently offer MCV in 10-dose vials and BCG in 20-dose vials; 10-dose vials are used for both vaccines in Vietnam. Unused doses in vials of these reconstituted vaccines must be discarded within 6 hours. METHODS: Key informant interviews (KIIs) were conducted with frontline HCWs in Senegal, Vietnam, and Zambia. In Senegal and Vietnam, the KIIs were conducted as part of broader formative research; in Zambia, KIIs were conducted in control districts using 10-dose MCV vials only and in intervention districts that switched from 10- to 5-dose vials during the study. During analysis, themes common to all 3 countries were synthesized. Critical themes relevant to country contexts were also examined. RESULTS: HCWs in all 3 countries preferred containers with fewer doses for BCG and MCV to reduce wastage and increase the likelihood of vaccinating every eligible child. HCWs in Senegal and HCWs using 10-dose vials in Zambia reported sending unvaccinated children away because not enough children were present to warrant opening a new vial. In Vietnam, where sessions are typically held monthly, and in Zambia when the 5-dose vials were used, almost all HCWs reported opening a vial of MCV for even 1 child. DISCUSSION: HCWs prefer vials with fewer DPC. Their concerns about balancing coverage and wastage influence their decisions to vaccinate every eligible child; and their perspectives are crucial to ensuring that all target populations are reached with vaccines in a timely manner.


Subject(s)
Immunization Programs , Vaccination , Child , Health Personnel , Humans , Measles Vaccine , Senegal , Vietnam , Zambia
6.
Molecules ; 25(6)2020 Mar 23.
Article in English | MEDLINE | ID: mdl-32209997

ABSTRACT

Four new polyhydroxylated steroids 1-4 were isolated along with two previously known related steroids 5 and 6 from the methanolic extract of the starfish Anthenoides laevigatus collected off the coastal waters of Vietnam. Structures of new compounds were substantially elucidated by one-dimensional (1D) and two-dimensional (2D) NMR spectroscopy and HRESIMS techniques. Heptaol 1 and hexaol 2 contain the common 5α-cholestane skeleton, while hexaol 3 and heptaol 4 have the rare among starfish steroid compounds 5ß-cholestane skeleton. Compounds 1, 5, and 6 do not show cytotoxic effects against normal JB6 Cl41 and cancer HT-29 and MDA-MB-231 cells, however they inhibit cell proliferation and colony formation of cancer HT-29 and MDA-MB-231 cells.


Subject(s)
Antineoplastic Agents , Cell Proliferation/drug effects , Neoplasms/drug therapy , Starfish/chemistry , Steroids , Animals , Antineoplastic Agents/chemistry , Antineoplastic Agents/isolation & purification , Antineoplastic Agents/pharmacology , HT29 Cells , Humans , Molecular Structure , Neoplasms/metabolism , Neoplasms/pathology , Nuclear Magnetic Resonance, Biomolecular , Steroids/chemistry , Steroids/isolation & purification , Steroids/pharmacology , Vietnam
7.
Ther Apher Dial ; 24(5): 554-560, 2020 Oct.
Article in English | MEDLINE | ID: mdl-31856402

ABSTRACT

Tumor necrosis factor alpha (TNF-α) is an inflammatory cytokine produced during acute inflammation. Few studies have evaluated the association between serum TNF-α and its receptors and their clinical outcomes in hemodialysis patients. However, a study assessing patients using a low-flux dialyzer reuse has not been conducted yet. The serum TNF-α concentrations of 319 prevalent hemodialysis patients (mean age, 45 ± 15 years; median duration of hemodialysis, 48 [interquartile range, 26-79] months; 185 males and 134 females) was examined to predict their 3-year mortality. The patients were divided into tertiles according to their serum TNF-α concentrations: T1 (n = 106; serum TNF-α concentration, <41.22 pg/mL), T2 (n = 106; serum TNF-α level, from 41.22 to 67.28 pg/mL), and T3 (n = 107; serum TNF-α concentration, ≥ 67.29 pg/mL). During the 36-month follow-up period, a total of 50 (15.7%) patients died from all causes. The Kaplan-Meier analysis revealed that the all-cause mortality in T3 was significantly higher compared to that in T1 and T2 (log-rank test, P < .001). The serum TNF-α level was a significant predictor for all-cause mortality (area under the curve = 0.887, P < .001, cutoff value, 89.812 pg/mL, sensitivity = 76%, specificity = 96.3%). The serum TNF-α level was a better predictor of mortality than the duration of hemodialysis and serum albumin, serum high-sensitivity C-reactive protein, and serum beta-2 microglobulin concentrations. The serum TNF-α concentration was a good predictor of the 3-year mortality in low-flux hemodialysis patients.


Subject(s)
Kidney Failure, Chronic/mortality , Kidney Failure, Chronic/therapy , Renal Dialysis/mortality , Tumor Necrosis Factor-alpha/blood , Adult , Biomarkers/blood , Female , Humans , Kaplan-Meier Estimate , Kidney Failure, Chronic/blood , Male , Middle Aged , Proportional Hazards Models , Renal Dialysis/methods , Renal Dialysis/statistics & numerical data , Survival Analysis , Vietnam/epidemiology
8.
Hum Reprod Open ; 2019(2): hoz006, 2019.
Article in English | MEDLINE | ID: mdl-30937394

ABSTRACT

STUDY QUESTIONS: Does ICSI result in a higher live birth rate as compared with conventional IVF in couples with non-male factor infertility? WHAT IS KNOWN ALREADY: ICSI is primarily indicated for severe male factor infertility. While the use of ICSI for couples with non-male factor infertility has been increasing worldwide, this is not supported by data from randomised controlled trials. Evidence from non-randomised studies suggest no benefit from ICSI compared with conventional IVF in non-male factor infertility, if not a harm. STUDY DESIGN SIZE DURATION: This randomised, open-label, multi-centre trial aims to compare the effectiveness of one ICSI cycle and one conventional IVF cycle in infertile couples with non-male factor infertility. A total of 1064 couples will be randomly allocated to an ICSI group and a conventional IVF group. The estimated duration of the study is 30 months. PARTICIPANTS/MATERIALS SETTING METHODS: Eligible couples are those whose husbands' total sperm count and motility are normal, have undergone ≤2 previous IVF/ICSI attempts, use antagonist protocol for ovarian stimulation, agree to have ≤2 embryos transferred and are not participating in another IVF study at the same time. Women undergoing IVM cycles, using frozen semen or having a poor fertilisation (≤25%) in previous cycle will not be eligible. Couples will be randomised to undergo ICSI or conventional IVF (1:1) with ongoing pregnancy resulting in live birth after the first embryo transfer of the started treatment cycle as the primary endpoint. All analyses will be conducted on an intention-to-treat basis. Effect sizes will be summarised as relative risk (RR), with precision evaluated by 95% CIs. STUDY FUNDING/COMPETING INTERESTS: All authors declare having no conflict of interests with regards to this trial. This work was supported by a grant from MSD [MISP #57508]. TRIAL REGISTRATION NUMBER: NCT03428919. TRIAL REGISTRATION DATE: 8 February 2018. DATE OF FIRST PATIENT'S ENROLMENT: 16 March 2018.

9.
Chem Biodivers ; 16(1): e1800401, 2019 Jan.
Article in English | MEDLINE | ID: mdl-30417533

ABSTRACT

In our research on biologically active compounds from Vietnamese marine invertebrates, rare melibiose-containing glycosphingolipids were found in a sample of a sponge-coral association (Desmapsamma anchorata/Carijoa riisei). Melibiosylceramides were analyzed as constituents of some multi-component RP-HPLC fractions, and the structures of 14 new (1b, 3b, 4a-4c, 6a-6c, 8b, 9a, 9b, 10b, 11a, 11b) and five known (2b, 5a-5c, 7b) natural compounds were elucidated using NMR, mass spectrometry, optical rotation, and chemical transformations. These α-d-Galp-(1→6)-ß-d-Glcp-(1 ↔ 1)-ceramides (presumably sponge-derived compounds) were shown to contain phytosphingosine-type n-t17:0 (1), (6E)-n-t17:1 (2), i-t17:0 (3), n-t18:0 (4), (6E)-n-t18:1 (5), i-t18:0 (6), (6E)-i-t18:1 (7), i-t19:0 (8), (6E)-i-t19:1 (9), ai-t19:0 (10), and (6E)-ai-t19:1 (11) backbones N-acylated with saturated straight-chain (2R)-2-hydroxy C21 (a), C22 (b), and C23 (c) acids. Characteristic trends in the fragmentations of the terminal parts of tetraacetylated normal-chain and iso- and anteiso-branched sphingoid bases were observed using GC/MS. The total sum of melibiosylceramides and compound 5b caused a reduction in colony formation of human melanoma cells.


Subject(s)
Anthozoa/chemistry , Biological Products/chemistry , Glycosphingolipids/analysis , Melibiose/analysis , Porifera/chemistry , Animals , Biological Products/isolation & purification , Biomarkers/analysis , Carbon-13 Magnetic Resonance Spectroscopy , Cell Line, Tumor , Cell Proliferation/drug effects , Cerebrosides/chemistry , Cerebrosides/pharmacology , Chromatography, High Pressure Liquid/methods , Chromatography, Reverse-Phase/methods , Drug Screening Assays, Antitumor , Esters , Fatty Acids, Nonesterified/chemistry , Gas Chromatography-Mass Spectrometry , Glycosphingolipids/chemistry , Glycosphingolipids/pharmacology , Humans , Melibiose/pharmacology , Proton Magnetic Resonance Spectroscopy , Sugars/analysis
10.
Biomicrofluidics ; 12(4): 044119, 2018 Jul.
Article in English | MEDLINE | ID: mdl-30174777

ABSTRACT

A custom-built mask aligner (CBMA), which fundamentally covers all the key features of a commercial mask aligner, while being low cost and light weight and having low power consumption and high accuracy, is constructed. The CBMA is composed of a custom high fidelity light emitting diode light source, a vacuum chuck, a mask holder, high-precision translation and rotation stages, and high resolution digital microscopes. The total cost of the system is under $7500, which is over ten times cheaper than a comparable commercial system. It produces a collimated ultraviolet illumination of 1.8-2.0 mW cm-2 over an area of a standard 4-in. wafer, at the plane of photoresist exposure, and the alignment accuracy is characterized to be <3 µm, which is sufficient for most microfluidic applications. Moreover, this manuscript provides detailed descriptions of the procedures needed to fabricate multilayered master molds using our CBMA. Finally, the capabilities of the CBMA are demonstrated by fabricating two- and three-layer masters for micro-scale devices, commonly encountered in biomicrofluidic applications. The former is a flow-free chemical gradient generator, and the latter is an addressable microfluidic stencil. Scanning electron microscopy is used to confirm that the master molds contain the intended features of different heights.

11.
Chem Biodivers ; 15(3): e1700553, 2018 Mar.
Article in English | MEDLINE | ID: mdl-29356326

ABSTRACT

Six new polyhydroxysteroidal glycosides, anthenosides S1  - S6 (1 - 6), along with a mixture of two previously known related glycosides, 7 and 8, were isolated from the methanolic extract of the starfish Anthenea sibogae. The structures of 1 - 6 were established by NMR and HR-ESI-MS techniques as well as by chemical transformations. All new compounds have a 5α-cholest-8(14)-ene-3α,6ß,7ß,16α-tetrahydroxysteroidal nucleus and differ from majority of starfish glycosides in positions of carbohydrate moieties at C(7) and C(16) (1 - 4, 6) or only at C(16) (5). The 4-O-methyl-ß-d-glucopyranose residue (2) and Δ24 -cholestane side chain (3) have not been found earlier in the starfish steroidal glycosides. The mixture of 7 and 8 slightly inhibited the proliferation of human breast cancer T-47D cells and decreased the colony size in the colony formation assay.


Subject(s)
Antineoplastic Agents, Phytogenic/pharmacology , Glycosides/pharmacology , Hydroxysteroids/pharmacology , Rhizophoraceae/chemistry , Animals , Antineoplastic Agents, Phytogenic/chemistry , Antineoplastic Agents, Phytogenic/isolation & purification , Cell Line, Tumor , Cell Proliferation/drug effects , China , Dose-Response Relationship, Drug , Drug Screening Assays, Antitumor , Glycosides/chemistry , Glycosides/isolation & purification , Humans , Hydroxysteroids/chemistry , Hydroxysteroids/isolation & purification , Magnetic Resonance Spectroscopy , Molecular Conformation , Starfish , Structure-Activity Relationship
12.
J Voice ; 32(3): 363-366, 2018 May.
Article in English | MEDLINE | ID: mdl-28778373

ABSTRACT

OBJECTIVE: Contact granulomas are benign, exophytic inflammatory lesions of the larynx that typically arise on or near the vocal process of the arytenoid cartilage. The most common management options include voice therapy and antireflux pharmacotherapy, intralesional steroid injections, botulinum toxin injections, and surgical excision. In-office Botox injection into the lateral cricoarytenoid (LCA) muscle can be effective even for recurrent granulomas. STUDY DESIGN: This is a retrospective chart review and literature review. METHOD: We reviewed more than 400 charts and included two patients, who underwent in-office injection with botulinum toxin A into LCA muscles bilaterally, after previously failing both conservative and surgical management. RESULTS: Both cases showed significant improvement of the laryngeal granulomas after 6 months and a single botulinum toxin injection. Both cases were initially grade III granuloma that improved to grade I. CONCLUSIONS: In-office injection of botulinum toxin A targeting the LCA muscle appears to be a safe and effective treatment modality in refractory laryngeal granuloma.


Subject(s)
Acetylcholine Release Inhibitors/administration & dosage , Botulinum Toxins/administration & dosage , Granuloma, Laryngeal/drug therapy , Laryngeal Muscles/drug effects , Vocal Cords/drug effects , Voice Disorders/drug therapy , Voice Quality/drug effects , Acetylcholine Release Inhibitors/adverse effects , Adult , Botulinum Toxins/adverse effects , Electromyography , Female , Granuloma, Laryngeal/diagnosis , Granuloma, Laryngeal/physiopathology , Humans , Injections, Intramuscular , Laryngeal Muscles/physiopathology , Laryngoscopy , Male , Middle Aged , Recovery of Function , Retrospective Studies , Stroboscopy , Treatment Outcome , Video Recording , Vocal Cords/physiopathology , Voice Disorders/diagnosis , Voice Disorders/physiopathology
13.
Sci Rep ; 7(1): 10465, 2017 09 05.
Article in English | MEDLINE | ID: mdl-28874790

ABSTRACT

Delivering liquid through the void spaces in porous metals is a daunting challenge for a variety of emerging interface technologies ranging from battery electrodes to evaporation surfaces. Hydraulic transport characteristics of well-ordered porous media are governed by the pore distribution, porosity, and morphology. Much like energy transport in polycrystalline solids, hydraulic transport in semi-ordered porous media is predominantly limited by defects and grain boundaries. Here, we report the wicking performances for porous copper inverse opals having pore diameters from 300 to 1000 nm by measuring the capillary-driven liquid rise. The capillary performance parameter within single crystal domain (K ij /R eff = 10-3 to 10-2 µm) is an order of magnitude greater than the collective polycrystal (K eff /R eff = ~10-5 to 10-3 µm) due to the hydraulic resistances (i.e. grain boundaries between individual grains). Inspired by the heterogeneity found in biological systems, we report that the capillary performance parameter of gradient porous copper (K eff /R eff = ~10-3 µm), comparable to that of single crystals, overcomes hydraulic resistances through providing additional hydraulic routes in three dimensions. The understanding of microscopic liquid transport physics through porous crystals and across grain boundaries will help to pave the way for the spatial design of next-generation heterogeneous porous media.

14.
Mucosal Immunol ; 10(2): 520-530, 2017 03.
Article in English | MEDLINE | ID: mdl-27461178

ABSTRACT

Mucosal antigen-specific CD4 T-cell responses to intestinal pathogens remain incompletely understood. Here we examined the CD4 T-cell response after oral infection with an internalin A 'murinized' Listeria monocytogenes (Lm). Oral Lm infection induced a robust endogenous listeriolysin O (LLO)-specific CD4 T-cell response with distinct phenotypic and functional characteristics in the intestine. Circulating LLO-specific CD4 T cells transiently expressed the 'gut-homing' integrin α4ß7 and accumulated in the intestinal lamina propria and epithelium where they were maintained independent of interleukin (IL)-15. The majority of intestinal LLO-specific CD4 T cells were CD27- Ly6C- and CD69+ CD103- while the lymphoid LLO-specific CD4 T cells were heterogeneous based on CD27 and Ly6C expression and predominately CD69-. LLO-specific effector CD4 T cells transitioned into a long-lived memory population that phenotypically resembled their parent effectors and displayed hallmarks of residency. In addition, intestinal effector and memory CD4 T cells showed a predominant polyfunctional Th1 profile producing IFNγ, TNFα, and IL-2 at high levels with minimal but detectable levels of IL-17A. Depletion of CD4 T cells in immunized mice led to elevated bacterial burden after challenge infection highlighting a critical role for memory CD4 T cells in controlling intestinal intracellular pathogens.


Subject(s)
Immunologic Memory , Intestinal Mucosa/metabolism , Listeria monocytogenes/immunology , Listeriosis/immunology , Th1 Cells/immunology , Administration, Oral , Animals , Antigens, CD/metabolism , Bacterial Proteins/immunology , Bacterial Proteins/metabolism , Bacterial Toxins/immunology , Cell Differentiation , Cells, Cultured , Cytokines/metabolism , Heat-Shock Proteins/immunology , Hemolysin Proteins/immunology , Integrin alpha4/metabolism , Integrin beta Chains/metabolism , Intestinal Mucosa/immunology , Lymphocyte Activation , Mice , Mice, Inbred C57BL , Mice, Knockout , Receptors, Lymphocyte Homing/metabolism
15.
Infect Genet Evol ; 41: 73-83, 2016 07.
Article in English | MEDLINE | ID: mdl-27016374

ABSTRACT

The fungal pathogen, Ceratocystis manginecans, has caused serious canker and wilt disease on Mangifera indica (mango), on legume tree species in Oman and Pakistan and on Acacia spp. in Indonesia. A Ceratocystis species, with similar morphology to C. manginecans, has recently been reported in Vietnam, causing severe disease of Acacia trees. Previous population genetic studies on isolates from M. indica in Oman and Pakistan have shown that the pathogen represents a single clonal haplotype, indicative of an introduced pathogen. The aim of this study was to investigate the genetic diversity and population structure of 160 C. manginecans isolates, from four host-associated populations from Oman, Pakistan, Indonesia and Vietnam. This was done by applying a combination of 14 previously developed microsatellite markers and a new set, designed in this study from two different C. manginecans genomes. Sequence data confirmed that the isolates in Vietnam are the same species as those in Indonesia and were thus identified as C. manginecans. Unlike the populations in Oman and Pakistan, relatively high levels of genetic variation were found for the isolates from Indonesia and Vietnam. The Vietnam population was significantly differentiated from the other populations and isolates from this area had the highest level of genetic diversity thus far encountered for the pathogen.


Subject(s)
Ascomycota/genetics , DNA, Fungal/genetics , DNA, Ribosomal Spacer/genetics , Genome, Fungal , Phylogeny , Trees/microbiology , Acacia/microbiology , Ascomycota/classification , Ascomycota/isolation & purification , Asia, Southeastern , Genetic Variation , Haplotypes , Mangifera/microbiology , Microsatellite Repeats , Phylogeography , Plant Diseases/microbiology
16.
Phys Med ; 31(8): 861-874, 2015 Dec.
Article in English | MEDLINE | ID: mdl-26653251

ABSTRACT

Understanding the fundamental mechanisms involved in the induction of biological damage by ionizing radiation remains a major challenge of today's radiobiology research. The Monte Carlo simulation of physical, physicochemical and chemical processes involved may provide a powerful tool for the simulation of early damage induction. The Geant4-DNA extension of the general purpose Monte Carlo Geant4 simulation toolkit aims to provide the scientific community with an open source access platform for the mechanistic simulation of such early damage. This paper presents the most recent review of the Geant4-DNA extension, as available to Geant4 users since June 2015 (release 10.2 Beta). In particular, the review includes the description of new physical models for the description of electron elastic and inelastic interactions in liquid water, as well as new examples dedicated to the simulation of physicochemical and chemical stages of water radiolysis. Several implementations of geometrical models of biological targets are presented as well, and the list of Geant4-DNA examples is described.


Subject(s)
DNA/chemistry , Models, Molecular , Monte Carlo Method , Water/chemistry , Chemical Phenomena , Humans
17.
Science ; 346(6212): 996-1000, 2014 Nov 21.
Article in English | MEDLINE | ID: mdl-25414313

ABSTRACT

We introduce the antibody landscape, a method for the quantitative analysis of antibody-mediated immunity to antigenically variable pathogens, achieved by accounting for antigenic variation among pathogen strains. We generated antibody landscapes to study immune profiles covering 43 years of influenza A/H3N2 virus evolution for 69 individuals monitored for infection over 6 years and for 225 individuals pre- and postvaccination. Upon infection and vaccination, titers increased broadly, including previously encountered viruses far beyond the extent of cross-reactivity observed after a primary infection. We explored implications for vaccination and found that the use of an antigenically advanced virus had the dual benefit of inducing antibodies against both advanced and previous antigenic clusters. These results indicate that preemptive vaccine updates may improve influenza vaccine efficacy in previously exposed individuals.


Subject(s)
Antibodies, Viral/immunology , Influenza A Virus, H3N2 Subtype/immunology , Influenza Vaccines/immunology , Influenza, Human/immunology , Vaccination , Antibodies, Viral/blood , Antigenic Variation/genetics , Antigenic Variation/immunology , Evolution, Molecular , Humans , Influenza A Virus, H3N2 Subtype/genetics , Influenza, Human/blood , Influenza, Human/prevention & control
18.
Rev Epidemiol Sante Publique ; 60(6): 437-46, 2012 Dec.
Article in French | MEDLINE | ID: mdl-23137871

ABSTRACT

BACKGROUND: Cervical cancer (CC) is almost always induced by some oncogenic types of human papillomavirus (HPV). In Vietnam, it is the first leading cause of cancer in women, with highest prevalence in Ho Chi Minh City (HCMC). Since 2006, prevention of the CC has been improved by licensure of recombinant vaccines directed against HPV 16 and 18, effective when administered before the age of first sexual intercourse. A national program for routine immunization of pre-adolescent girls in addition to cytological screening of adult women would greatly reduce the impact of CC in Vietnam but vaccines remain expensive and it is unclear how this strategy would be accepted by the target population. The aim of this study was to assess the acceptability of HPV vaccination by pediatricians, mothers with a daughter aged 9-15 years and young women aged 16-26 years in HCMC. METHODS: Between March and June 2010, a cross-sectional survey of knowledge and attitudes was administered to 115 pediatricians in the pediatric hospital, 210 mothers and 400 young women attending the gynecology department of the University Hospital. RESULTS: Pediatricians generally had a good perception of the risk but they still lacked knowledge about HPV vaccination, given by 66% of them. Among mothers, 18% knew the relationship between HPV infection and CC, 43% had heard of HPV vaccination and 40% agreed to vaccinate their daughter. Among young women, 35% knew the risk, 49% knew the vaccine and 38% wanted to be vaccinated. Level of education, amount of income and celibacy were positively related to intention to be vaccinated. The lack of information on HPV vaccination and the high cost of vaccines were the main causes of refusal or indecision. CONCLUSION: Routine HPV vaccination of girls in HCMC will be well accepted by the population if a large campaign of health education is implemented by the government and if the affordability of vaccines is facilitated.


Subject(s)
Papillomaviridae/immunology , Papillomavirus Infections/prevention & control , Papillomavirus Vaccines/administration & dosage , Patient Acceptance of Health Care/statistics & numerical data , Uterine Cervical Neoplasms/prevention & control , Adolescent , Adult , Child , Cross-Sectional Studies , Female , Humans , Mothers , Uterine Cervical Neoplasms/virology , Vietnam , Young Adult
19.
Steroids ; 75(12): 897-904, 2010 Dec.
Article in English | MEDLINE | ID: mdl-20493893

ABSTRACT

Five new steroidal compounds, including an unusual glucoside, along with several known steroids were isolated from the starfish Archaster typicus collected in shallow waters of Quang Ninh province (Vietnam). Three new compounds are 27-nor-cholestane derivatives and the other two are 24,26-dihydroxycholestane derivatives. A biogenesis pathway for the unusual side chain of 27-nor-cholestane derivatives is proposed. Isolated compounds presented moderate toxic effects in the sperm- and 8-blastomere tests on embryonal development of the sea urchin Strongylocentrotusintermedius.


Subject(s)
Seawater , Starfish/chemistry , Steroids/chemistry , Steroids/isolation & purification , Animals , Ethanol/chemistry , Fertilization/drug effects , Hydroxylation , Steroids/toxicity , Strongylocentrotus/drug effects , Strongylocentrotus/embryology , Strongylocentrotus/physiology , Vietnam
20.
Bioorg Med Chem Lett ; 20(12): 3826-30, 2010 Jun 15.
Article in English | MEDLINE | ID: mdl-20493687

ABSTRACT

New asterosaponins archasterosides A (1), B (2), and the known regularoside A (3) were isolated from the Vietnamese starfish Archaster typicus and structurally elucidated by extensive NMR techniques and chemical transformations. Compounds 1-3 showed moderate cytotoxic activities against HeLa and mouse JB6 P(+) Cl41 cell lines. The most active, 2, induced basal AP-1- and p53-, but not NF-kappaB-transcriptional activations in JB6 Cl41 cells.


Subject(s)
Antineoplastic Agents/isolation & purification , Saponins/pharmacology , Starfish/chemistry , Animals , Cell Line, Tumor , HeLa Cells , Humans , Magnetic Resonance Spectroscopy , Mice , Molecular Structure , NF-kappa B/genetics , Saponins/isolation & purification , Transcription Factor AP-1/genetics , Transcriptional Activation/drug effects , Tumor Suppressor Protein p53/genetics
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