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1.
Heliyon ; 10(10): e31503, 2024 May 30.
Article in English | MEDLINE | ID: mdl-38818209

ABSTRACT

Recently, agriculture systems have faced numerous challenges involving sustainable nutrient use efficiency and feeding, environmental pollution especially heavy metals (HMs), infection of harmful microorganisms, and maintenance of crop production quality during postharvesting and packaging. Nanotechnology and nanomaterials have emerged as powerful tools in agriculture applications that provide alternatives or support traditional methods. This review aims to address and highlight the current overarching issue and various implementation strategies of nanotechnology for sustainable agriculture development. In particular, the current progress of different nano-fertilizers (NFs) systems was analyzed to show their advances in enhancing the uptake and translocations in plants and improving nutrient bioavailability in soil. Also, the design strategy and application of nanotechnology for rapid detection of HMs and pathogenic diseases in plant crops were emphasized. The engineered nanomaterials have great potential for biosensors with high sensitivity and selectivity, high signal throughput, and reproducibility through various detection approaches such as Raman, colorimetric, biological, chemical, and electrical sensors. We obtain that the development of microfluidic and lab-on-a-chip (LoC) technologies offers the opportunity to create on-site portable and smart biodevices and chips for real-time monitoring of plant diseases. The last part of this work is a brief introduction to trends in nanotechnology for harvesting and packaging to provide insights into the overall applications of nanotechnology for crop production quality. This review provides the current advent of nanotechnology in agriculture, which is essential for further studies examining novel applications for sustainable agriculture.

3.
PLoS One ; 18(11): e0293888, 2023.
Article in English | MEDLINE | ID: mdl-37963172

ABSTRACT

Type 2 diabetes is considered one of the top ten life-threatening diseases worldwide. Following economic growth, obesity and metabolic syndrome became the most common risk factor for type 2 diabetes. In this regard, high-fat diet-fed C57BL/6J mouse model is widely used for type 2 diabetes pathogenesis and novel therapeutics development. However, criteria for classifying type 2 diabetes progressive stages in this mouse model are yet to be determined, led to the difficulty in experimental end-point decision. In this study, we fed C57BL/6J male mice with 45% high-fat diet, which is physiologically close to human high-fat consumption, and evaluated the progression of type 2 diabetes. After consuming high-fat diet for 4 weeks, mice developed metabolic syndrome, including obesity, significant increase of fasting plasma cholesterol level, elevation of both C-peptide and fasting blood glucose levels. By combining both fasting blood glucose test and 2-hour-oral glucose tolerance test, our results illustrated clear progressive stages from metabolic syndrome into pre-diabetes before onset of type 2 diabetes in C57BL/6J mice given a 45% high-fat diet. Besides, among metabolic measurements, accumulating body weight gain > 16.23 g for 12 weeks could be utilized as a potential parameter to predict type 2 diabetes development in C57BL/6J mice. Thus, these results might support future investigations in term of selecting appropriate disease stage in high-fat diet-fed C57BL/6J mouse model for studying early prevention and treatment of type 2 diabetes.


Subject(s)
Diabetes Mellitus, Type 2 , Metabolic Syndrome , Humans , Male , Mice , Animals , Glucose Tolerance Test , Diet, High-Fat/adverse effects , Blood Glucose/metabolism , Diabetes Mellitus, Type 2/complications , Metabolic Syndrome/complications , Mice, Inbred C57BL , Obesity/metabolism , Disease Models, Animal , Fasting
4.
J Public Health Res ; 12(3): 22799036231196681, 2023 Jul.
Article in English | MEDLINE | ID: mdl-37693737

ABSTRACT

Background: Drugstores are preferred patients' channels of contact when getting minor ailments. Given the hike in both the prevalence and severity of influenza and acute childhood diarrhea, the role, and performances of pharmacy staff should be examined. Design and methods: A team of pharmacy students was voluntarily recruited and trained to play the role of simulated customer visiting 228 chosen community pharmacies in six districts in Can Tho city. This process is conducted from 2021 to 2022. Results: The study reveals detailed information about symptoms is the most common inquiry (99.2% in scenario 1). The consulting quality is poor, 85% of instances recorded to have no medical guidelines for influenza circumstances. Meanwhile, nearly four-fifths of pharmacists provide instructions on dosage intake. It is also found that length of services is statistically different between influenza and watery diarrhea (p < 0.05, CI = 95%). Conclusions: Clinical practices of community pharmacists, overall, are disappointing and far below expectations.

5.
Pharm. pract. (Granada, Internet) ; 21(2): 1-10, abr.-jun. 2023. ilus, tab, graf
Article in English | IBECS | ID: ibc-222786

ABSTRACT

Objectives: To access determinants of the intent of providing ETC medicines in non-prescription settings in community pharmacists in Can Tho, Vietnam in 2021. Additionally, we aimed to create a new measurement scale of degrees of effect for each factor. Methods: A cross-sectional research was conducted between June and October 2021. A self-administered questionnaire stemmed from the “Theory of Planned Behavior” (TPB), consisting of 24 statements on a 5-point Likert scale was mailed to targeted individuals. Exploratory factor analysis is the major instrument apart from the t-Test and ANOVA statistics. 120 pharmacy personnel working at 120 randomly chosen drugstores in Can Tho. Results: Subjective norms have been found to be the most influential factor, followed by perceived behavior controls, and positive attitudes toward the action of concern. TPB-based model is responsible for approximately 40% of the variance in the willingness to take action. Conclusion: It seems that community pharmacists’ decision toward prescription pharmaceuticals has not been academically attractive. Extra papers are necessary to understand the motives behind the execution of the behavior. (AU)


Subject(s)
Humans , Male , Female , Adult , Middle Aged , Pharmacists , Nonprescription Drugs , Products Commerce , Vietnam , Cross-Sectional Studies , Epidemiology, Descriptive , Surveys and Questionnaires , Factor Analysis, Statistical
7.
ACS Omega ; 8(7): 6679-6688, 2023 Feb 21.
Article in English | MEDLINE | ID: mdl-36844600

ABSTRACT

With the emergence of antibody-evasive omicron subvariants (BA.2.12.1, BA.4, and BA.5), which can compromise the efficacy of vaccination, it is of utmost importance to widen the finite therapeutic options for COVID-19. Although more than 600 co-crystal complexes of Mpro with inhibitors have been revealed, utilizing them to search for novel Mpro inhibitors remains limited. Although there were two major groups of Mpro inhibitors, covalent and noncovalent inhibitors, noncovalent inhibitors were our main focus due to the safety concerns with their covalent counterparts. Hence, this study aimed to explore Mpro noncovalent inhibition ability of phytochemicals extracted from Vietnamese herbals by combining multiple structure-based approaches. By closely inspecting 223 complexes of Mpro with noncovalent inhibitors, a 3D-pharmacophore model representing typical chemical features of Mpro noncovalent inhibitors was generated with good validation scores (sensitivity = 92.11%, specificity = 90.42%, accuracy = 90.65%, and goodness-of-hit score = 0.61). Afterward, the pharmacophore model was applied to explore the potential Mpro inhibitors from our in-house Vietnamese phytochemical database, revealing 18 substances, 5 of which were in vitro assayed. The remaining 13 substances were then examined by induced-fit molecular docking, revealing 12 suitable compounds. A machine-learning activity prediction model was developed to rank the hit, suggesting nigracin and calycosin-7-O-ß-glucopyranoside as promising Mpro natural noncovalent inhibitors.

8.
Ultrasound Med Biol ; 49(5): 1345-1350, 2023 05.
Article in English | MEDLINE | ID: mdl-36813583

ABSTRACT

OBJECTIVE: Alveolar crestal bone thickness and level provide important diagnostic and prognostic information for orthodontic treatment, periodontal disease management and dental implants. Ionizing radiation-free ultrasound has emerged as a promising clinical tool in imaging oral tissues. However, the ultrasound image is distorted when the wave speed of the tissue of interest is different from the mapping speed of the scanner and, therefore, the subsequent dimension measurements are not accurate. This study was aimed at deriving a correction factor that can be applied to the measurements to correct for discrepancy caused by speed variation. METHODS: The factor is a function of the speed ratio and the acute angle that the segment of interest makes with the beam axis perpendicular to the transducer. The phantom and cadaver experiments were designed to validate the method. DISCUSSION: The comparisons agree well with absolute errors not more than 4.9%. Dimension measurements on ultrasonographs can be properly corrected by applying the correction factor without recourse to the raw signals. CONCLUSION: The correction factor has reduced the measurement discrepancy on the acquired ultrasonographs for the tissue whose speed is different from the scanner's mapping speed.


Subject(s)
Cone-Beam Computed Tomography , Dental Implants , Humans , Alveolar Process/diagnostic imaging , Imaging, Three-Dimensional , Ultrasonography , Cadaver
9.
J Leukoc Biol ; 111(3): 539-551, 2022 03.
Article in English | MEDLINE | ID: mdl-34028877

ABSTRACT

Immunometabolism is rising as an intriguing topic that reveals the connection between immune cell function and metabolic processes. Especially, fatty acid metabolism plays an essential role in the dendritic cells (DCs) during the differentiation and maturation period. We questioned whether regulation of acetyl-CoA carboxylases 1 and 2-(ACC1/2), the core enzymes of fatty acid synthesis (FAS), would control DC function. Here, we report that blocking ACC1/2 to prevent FAS during DC maturation switched their cellular metabolism into fatty acid oxidation to fuel oxidative phosphorylation. This action turned DCs to utilize exogenous fatty acids to sustain their basal energy demand and maintain a stable cellular respiration rate. Coincidentally, under the ACC1/2 inhibitor treatment, LPS-treated DCs exhibited a semimaturation phenotype with a maturation-resistance feature, with decreased expression of costimulatory molecules including CD86 and CD40, along with the reduction of IL-12 and IL-6. The migratory capability of DCs has been known to relate to the glycolysis pathway, and here we showed that the ACC1/2 blockade did not affect the expression of CCR7 and DC migration. Furthermore, we found that under the ACC1/2 blocking condition, DCs pulsed with OVA failed to activate OVA-specific CD4+ T cell proliferation even though their antigen uptake capacity was intact. Together, our data suggest ACC1/2 as a promising target to control DC fate.


Subject(s)
Acetyl-CoA Carboxylase , Fatty Acids , Acetyl-CoA Carboxylase/genetics , Acetyl-CoA Carboxylase/metabolism , Dendritic Cells , Fatty Acids/metabolism , Lymphocyte Activation , Oxidative Phosphorylation
10.
Malar J ; 20(1): 264, 2021 Jun 11.
Article in English | MEDLINE | ID: mdl-34116665

ABSTRACT

BACKGROUND: Emergence of cross-resistance to current anti-malarial drugs has led to an urgent need for identification of potential compounds with novel modes of action and anti-malarial activity against the resistant strains. One of the most promising therapeutic targets of anti-malarial agents related to food vacuole of malaria parasite is haemozoin, a product formed by the parasite through haemoglobin degradation. METHODS: With this in mind, this study developed two-dimensional-quantitative structure-activity relationships (QSAR) models of a series of 21 haemozoin inhibitors to explore the useful physicochemical parameters of the active compounds for estimation of anti-malarial activities. The 2D-QSAR model with good statistical quality using partial least square method was generated after removing the outliers. RESULTS: Five two-dimensional descriptors of the training set were selected: atom count (a_ICM); adjacency and distance matrix descriptor (GCUT_SLOGP_2: the third GCUT descriptor using atomic contribution to logP); average total charge sum (h_pavgQ) in pKa prediction (pH = 7); a very low negative partial charge, including aromatic carbons which have a heteroatom-substitution in "ortho" position (PEOE_VSA-0) and molecular descriptor (rsynth: estimating the synthesizability of molecules as the fraction of heavy atoms that can be traced back to starting material fragments resulting from retrosynthetic rules), respectively. The model suggests that the anti-malarial activity of haemozoin inhibitors increases with molecules that have higher average total charge sum in pKa prediction (pH = 7). QSAR model also highlights that the descriptor using atomic contribution to logP or the distance matrix descriptor (GCUT_SLOGP_2), and structural component of the molecules, including topological descriptors does make for better anti-malarial activity. CONCLUSIONS: The model is capable of predicting the anti-malarial activities of anti-haemozoin compounds. In addition, the selected molecular descriptors in this QSAR model are helpful in designing more efficient compounds against the P. falciparum 3D7A strain.


Subject(s)
Antimalarials/chemistry , Hemeproteins/drug effects , Models, Chemical , Quantitative Structure-Activity Relationship , Antimalarials/pharmacology , Hemeproteins/chemistry , Humans , Least-Squares Analysis , Malaria, Falciparum/parasitology , Malaria, Falciparum/prevention & control
11.
Biochem Biophys Res Commun ; 534: 1053-1058, 2021 01 01.
Article in English | MEDLINE | ID: mdl-33160622

ABSTRACT

High mobility group (HMGB1) is an alarmin known to be harmful to pancreatic beta cells and associated with diabetes mellitus pathogenesis and pancreatic islet graft failure. It has been long thought that the suppression of HMGB1 molecule is beneficial to the beta cells. However, recent studies have indicated that cytoplasmic HMGB1 (cHMGB1) could function as a modulator to relieve cells from apoptotic stress by autophagy induction. Particularly, pancreatic beta cells have been known to utilize the autophagy-to-apoptosis switch when exposed to hypoxia or lipotoxicity. This study aimed to investigate the beta cells under hypoxic and lipotoxic stress while utilizing a small molecule inhibitor of HMGB1, inflachromene (ICM) which can suppress cHMGB1 accumulation. It was revealed that under cellular stress, blockade of cHMGB1 accumulation decreased the viability of islet grafts, primary islets and MIN6 cells. MIN6 cells under cHMGB1 blockade along with lipotoxic stress showed decreased autophagic flux and increased apoptosis. Moreover, cHMGB1 blockade in HFD-fed mice produced unfavorable outcomes on their glucose tolerance. In sum, these results suggested the role of cHMGB1 within beta cell autophagy/apoptosis checkpoint. Given the importance of autophagy in beta cells under apoptotic stresses, this study might provide further insights regarding HMGB1 and diabetes.


Subject(s)
HMGB1 Protein/antagonists & inhibitors , Heterocyclic Compounds, 4 or More Rings/pharmacology , Insulin-Secreting Cells/cytology , Insulin-Secreting Cells/drug effects , Animals , Apoptosis/drug effects , Autophagy/drug effects , Cell Hypoxia , Cell Survival/drug effects , HMGB1 Protein/metabolism , Insulin-Secreting Cells/metabolism , Insulin-Secreting Cells/transplantation , Male , Mice, Inbred BALB C , Mice, Inbred C57BL , Mice, Inbred NOD , Swine
12.
Entropy (Basel) ; 22(11)2020 Oct 29.
Article in English | MEDLINE | ID: mdl-33286999

ABSTRACT

We study the nature of the smectic-isotropic phase transition using a mobile 6-state Potts model. Each Potts state represents a molecular orientation. We show that with the choice of an appropriate microscopic Hamiltonian describing the interaction between individual molecules modeled by a mobile 6-state Potts spins, we observe the smectic phase dynamically formed when we cool the molecules from the isotropic phase to low temperatures (T). In order to elucidate the order of the transition and the low-T properties, we use the high-performance Wang-Landau flat energy-histogram technique. We show that the smectic phase goes to the liquid (isotropic) phase by melting/evaporating layer by layer starting from the film surface with increasing T. At a higher T, the whole remaining layers become orientationally disordered. The melting of each layer is characterized by a peak of the specific heat. Such a succession of partial transitions cannot be seen by the Metropolis algorithm. The successive layer meltings/evaporations at low T are found to have a first-order character by examining the energy histogram. These results are in agreement with experiments performed on some smectic liquid crystals.

13.
Molecules ; 25(20)2020 Oct 13.
Article in English | MEDLINE | ID: mdl-33066044

ABSTRACT

Inhibition of human pancreatic lipase, a crucial enzyme in dietary fat digestion and absorption, is a potent therapeutic approach for obesity treatment. In this study, human pancreatic lipase inhibitory activity of aurone derivatives was explored by molecular modeling approaches. The target protein was human pancreatic lipase (PDB ID: 1LPB). The 3D structures of 82 published bioactive aurone derivatives were docked successfully into the protein catalytic active site, using AutoDock Vina 1.5.7.rc1. Of them, 62 compounds interacted with the key residues of catalytic trial Ser152-Asp176-His263. The top hit compound (A14), with a docking score of -10.6 kcal⋅mol-1, was subsequently submitted to molecular dynamics simulations, using GROMACS 2018.01. Molecular dynamics simulation results showed that A14 formed a stable complex with 1LPB protein via hydrogen bonds with important residues in regulating enzyme activity (Ser152 and Phe77). Compound A14 showed high potency for further studies, such as the synthesis, in vitro and in vivo tests for pancreatic lipase inhibitory activity.


Subject(s)
Benzofurans/chemistry , Enzyme Inhibitors/chemistry , Enzyme Inhibitors/pharmacology , Lipase/antagonists & inhibitors , Lipase/chemistry , Benzofurans/pharmacology , Catalytic Domain , Humans , Hydrogen Bonding , Ligands , Lipase/metabolism , Molecular Docking Simulation , Molecular Dynamics Simulation , Orlistat/chemistry
14.
Malar J ; 19(1): 298, 2020 Aug 21.
Article in English | MEDLINE | ID: mdl-32825818

ABSTRACT

BACKGROUND: Despite noticeable improvement in anti-malarial treatment, rapid growth of resistant malaria strains points out the need for continuous development of novel anti-malarials to fight the disastrous infection. Haemozoin is considered as a novel inhibitory pathway for new anti-malarial drugs, therefore, this study aimed to systematically review all articles investigating the correlation between anti-malarial and anti-haemozoin activities of anti-malarial compounds. METHODS: A literature search was conducted on 22 October 2017 in eight databases for relevant in vitro articles reporting the correlation between anti-malarial and anti-haemozoin of anti-malarial compounds, based on the constructed search terms and inclusion criteria. ToxRtool was used to assess quality of each study. RESULTS: A total of ten articles were included in the review. In vitro anti-malarial and anti-haemozoin activity had a good correlation for quinolines for sensitive strains (R2 ranging from 0.66 to 0.95) and xanthones (Spearman ρ = 0.886). However, these correlations were reached after removing some compounds which had non-detectable anti-malarial or anti-haemozoin effects. Other structures (acridines, pyrolidines) showed negligible correlation with Spearman ρ ranging from 0.095 to 0.381 for acridines, and r varying from 0.54 to 0.62 for pyrolidines. Some good correlations were only shown in a logarithmic manner or when the anti-malarial activity was normalized. CONCLUSION: The results raised a relative relationship between anti-haemozoin and in vitro anti-malarial activities. Some studies reported compounds that were effective in the inhibition of haemozoin formation, but failed to inhibit the parasite survival and vice versa. The correlation results in these studies were calculated after these compounds were removed from their analysis. The ability of anti-malarial compounds to accumulate inside the reaction site might strengthen their anti-malarial activity.


Subject(s)
Antimalarials/pharmacology , Hemeproteins/antagonists & inhibitors , Malaria, Falciparum/prevention & control , Plasmodium falciparum/drug effects , Protozoan Proteins/antagonists & inhibitors , Antimalarials/therapeutic use
15.
Neurosurg Focus ; 46(6): E9, 2019 06 01.
Article in English | MEDLINE | ID: mdl-31153151

ABSTRACT

OBJECTIVEFor stereotactic radiosurgery (SRS) planning, precise contouring of tumor boundaries and organs at risk is of utmost importance. Correct interpretation of standard neuroimaging (i.e., CT and MRI) can be challenging after previous surgeries or in cases of skull base lesions with complex shapes. The aim of this study was to evaluate the impact of 68Ga-DOTATOC PET/MRI on treatment planning for image-guided SRS by CyberKnife.METHODSThe authors retrospectively identified 11 meningioma treatments in 10 patients who received a 68Ga-DOTATOC PET/MRI prior to SRS. The planning target volume (PTV) used for the patients' treatment was defined as the reference standard. This was contoured by a treating radiosurgeon (RS0) using fused planning CT and PET/MRI data sets. The same tumors were then contoured by another experienced radiosurgeon (RS1) and by a less-experienced radiosurgeon (RS2), both blinded to PET data sets. A comparison of target volumes with focus on volume-based metrics and distance to critical structures was performed. RS1 and RS2 also filled in a questionnaire analyzing the confidence level and the subjective need for the implementation of PET data sets for contouring.RESULTSAnalysis showed a subjective personal preference for PET/MRI in all cases for both radiosurgeons, particularly in proximity to critical structures. The analysis of the planning volumes per physician showed significantly smaller RS2-PTV in comparison to RS1-PTV and to RS0-PTV, whereas the median volumes were comparable between RS1-PTV and RS2-PTV (median: RS0: 4.3 cm3 [IQR 3.4-6.5 cm3] and RS1: 4.5 cm3 [IQR 2.7-6 cm3] vs RS2: 2.6 cm3 [IQR 2-5 cm3]; p = 0.003). This was also reflected in the best spatial congruency between the 2 experienced physicians (RS0 and RS1). The percentage of the left-out volume contoured by RS1 and RS2 compared to RS0 with PET/MRI demonstrated a relevant left-out-volume portion in both cases with greater extent for the less-experienced radiosurgeon (RS2) (RS1: 19.1% [IQR 8.5%-22%] vs RS2: 40.2% [IQR 34.2%-53%]). No significant differences were detected regarding investigated critical structures.CONCLUSIONSThis study demonstrated a relevant impact of PET/MRI on target volume delineation of meningiomas. The extent was highly dependent on the experience of the treating physician. This preliminary study supports the relevance of 68Ga-DOTATOC PET/MRI as a tool for radiosurgical treatment planning of meningiomas.


Subject(s)
Cranial Irradiation , Gallium Radioisotopes , Magnetic Resonance Imaging , Meningeal Neoplasms/diagnostic imaging , Meningioma/diagnostic imaging , Multimodal Imaging , Octreotide/analogs & derivatives , Organometallic Compounds , Positron-Emission Tomography , Preoperative Care/methods , Radiopharmaceuticals , Radiosurgery , Robotic Surgical Procedures , Attitude of Health Personnel , Consumer Behavior , Humans , Meningeal Neoplasms/surgery , Meningioma/surgery , Retrospective Studies , Surgeons/psychology , Tumor Burden
16.
Ultrasonics ; 96: 40-47, 2019 Jul.
Article in English | MEDLINE | ID: mdl-30947073

ABSTRACT

This article is concerned with the application of reciprocity in computing guided wave motions generated by a time-harmonic load in a layer of uniform thickness joined to a half-space. Explicit expressions for free Rayleigh waves and Love waves propagating in the layered half-space are introduced. Exact solutions of Rayleigh waves and Love waves are derived from reciprocity relations between an actual state - guided waves generated by a time-harmonic line load and a virtual state - an appropriately chosen free wave traveling in the structure. Scattered amplitudes of the wave motions are thus determined. The validation of the reciprocity approach is shown through the computation of the lowest Rayleigh wave mode in the layered half-space, which approaches the calculation of the Rayleigh surface wave in the half-space once the layer thickness approaches zero in the limit.

17.
J Public Health Manag Pract ; 24 Suppl 2: S74-S81, 2018.
Article in English | MEDLINE | ID: mdl-29369260

ABSTRACT

Health sector decentralization has created an urgent need to strengthen public health management capacity in many countries throughout the developing world. This article describes the establishment of a national management training network in Vietnam that used Project-Based Learning to strengthen management competencies of HIV program workers and linked training to measurable improvement in HIV/AIDS public health program outcomes. Skills were taught using a combination of classroom learning and mentored fieldwork. From 2005 to 2015, 827 HIV/AIDS program managers were trained with this method throughout Vietnam by trainers in 3 regional training centers. A total of 218 applied learning projects were carried out by trainees during this period; 132 resulted in measurable improvements in HIV/AIDS program outputs, and 86 produced well-organized plans for implementing, monitoring, and evaluating HIV/AIDS intervention strategies. Vietnam's management training network represents an important advancement in public health workforce development that helps prepare workers for new roles and responsibilities in a decentralized health system.


Subject(s)
Capacity Building/methods , Delivery of Health Care/methods , Public Health/standards , Capacity Building/organization & administration , Capacity Building/trends , Delivery of Health Care/trends , Government Programs , Humans , Politics , Public Health/statistics & numerical data , Quality Improvement/trends , Vietnam
18.
Drug Saf ; 41(2): 151-159, 2018 02.
Article in English | MEDLINE | ID: mdl-28975584

ABSTRACT

Drug safety issues in developing countries are complex and sensitive, and health authorities cannot always simply implement decisions from developed countries because the health system, disease patterns, and lists of marketed drugs all differ. A system for proactive and effective surveillance of drugs in each nation is needed to identify and manage the exact drug-related problems faced by patients in these countries. Vietnam launched its university-based National Drug Information and Adverse Drug Reaction Monitoring Centre (NDIADRMC) in 2009, a significant step towards catching up with international trends. Although the center is still in its infancy and has limited resources, it has attained some achievements and largely met the minimum World Health Organization requirements for a functional pharmacovigilance center. The number of reports has increased rapidly, with some important signals generated from the national database leading to regulatory actions at a national level. In addition, this system can help detect drug-quality problems that are less common in developed countries. The success of the quantity and quality of reporting, risk assessment, and communication is still limited compared with more developed systems. A number of opportunities remain to enhance the system, particularly in risk communication and evaluation of the impact of pharmacovigilance, and to apply reporting outcomes to reduce drug-related risks throughout the country. More internal and external support is needed to develop a stronger and more comprehensive pharmacovigilance system.


Subject(s)
Adverse Drug Reaction Reporting Systems/organization & administration , Developing Countries/statistics & numerical data , Drug-Related Side Effects and Adverse Reactions/prevention & control , Pharmacovigilance , Drug Monitoring/statistics & numerical data , Humans , Vietnam , World Health Organization
19.
Acta Biotheor ; 64(4): 495-517, 2016 Dec.
Article in English | MEDLINE | ID: mdl-27770315

ABSTRACT

We investigate a system of two species exploiting a common resource. We consider both abiotic (i.e. with a constant resource supply rate) and biotic (i.e. with resource reproduction and self-limitation) resources. We are interested in the asymmetric competition where a given consumer is the locally superior resource exploiter (LSE) and the other is the locally inferior resource exploiter (LIE). They also interact directly via interference competition in the sense that LIE individuals can use two opposite strategies to compete with LSE individuals: we assume, in the first case, that LIE uses an avoiding strategy, i.e. LIE individuals go to a non-competition patch to avoids competition with LSE individuals, and in the second one, LIE uses an aggressive strategy, i.e. being very aggressive so that LSE individuals have to go to a non-competition patch. We further assume that there is no resource in the non-competition patch so that individuals have to come back to the competition patch for their maintenance, and the migration process acts on a fast time scale in comparison with demography and competition processes. The models show that being aggressive is efficient for LIE's survival and even provoke global extinction of the LSE and this result does not depend on the nature of resource.


Subject(s)
Behavior, Animal/physiology , Cats/psychology , Competitive Behavior/physiology , Models, Theoretical , Population Dynamics , Animals , Cats/classification , Cats/physiology , Computer Simulation
20.
Acta Biotheor ; 64(4): 519-536, 2016 Dec.
Article in English | MEDLINE | ID: mdl-27770316

ABSTRACT

We present a mathematical model of two competing marine species that are harvested. We consider three models according to different levels of complexity, without and with species refuge and density-independent and density-dependent species movement between fishing area and refuge. We particularly study the effects of the fishing pressure on the outcome of the competition. We focus on conditions that allow an inferior competitor to invade as a result of fishing pressure. The model is discussed in relationship to the case of the thiof and the octopus along the Atlantic West African coast. At the origin, the thiof was abundant and the octopus scarce in that region. Since, the fishing pressure has strongly increased in some fishing areas leading to the depletion of the thiof and the invasion of its competitor, the octopus.


Subject(s)
Competitive Behavior , Fisheries , Fishes/classification , Fishes/physiology , Models, Theoretical , Octopodiformes/physiology , Animals , Population Dynamics , Senegal
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