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1.
Bioengineering (Basel) ; 11(4)2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38671737

RESUMO

Chest X-ray (CXR) examination serves as a widely employed clinical test in medical diagnostics. Many studied have tried to apply artificial intelligence (AI) programs to analyze CXR images. Despite numerous positive outcomes, assessing the applicability of AI models for comprehensive diagnostic support remains a formidable challenge. We observed that, even when AI models exhibit high accuracy on one dataset, their performance may deteriorate when tested on another. To address this issue, we propose incorporating a variational information bottleneck (VIB) at the patch level to enhance the generalizability of diagnostic support models. The VIB introduces a probabilistic model aimed at approximating the posterior distribution of latent variables given input data, thereby enhancing the model's generalization capabilities on unseen data. Unlike the conventional VIB approaches that flatten features and use a re-parameterization trick to sample a new latent feature, our method applies the trick to 2D feature maps. This design allows only important pixels to respond, and the model will select important patches in an image. Moreover, the proposed patch-level VIB seamlessly integrates with various convolutional neural networks, offering a versatile solution to improve performance. Experimental results illustrate enhanced accuracy in standard experiment settings. In addition, the method shows robust improvement when training and testing on different datasets.

2.
Clin Case Rep ; 12(4): e8726, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38550741

RESUMO

An epidermoid cyst is a benign tumor in many locations. The symptoms of an epidermoid cyst depend on its location. The brain or spine MRI can confirm the lesion. Removing total decompression is the first choice in treatment with a symptomatic cyst.

3.
Phys Chem Chem Phys ; 25(41): 28296-28308, 2023 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-37830378

RESUMO

NaGdF4 nanocrystalline doped with different concentrations of Eu3+ ions were synthesized using the precipitation method. The structure and morphology of the material were investigated through the measurements of the XRD patterns and SEM images, respectively. The optical properties of the NaGdF4:Eu3+ nanocrystalline were studied in the framework of the Judd-Ofelt theory in which the Ωλ parameters were calculated by two methods: the traditional method using the luminescence spectra and the self-referenced method using the luminescence excitation spectra. In NaGdF4:Eu3+ nanocrystalline, the Gd3+ ions in the lattice act as sensitizer centers for the luminescence of Eu3+ ions under excitation at 272 and 310 nm. The energy transfer process from Gd3+ to Eu3+ causes the emission enhancement of Eu3+ ions. Upon excitation by the characteristic wavelengths of Gd3+, the luminescence efficiency of the Eu3+ ions in NaGdF4:Eu3+ is affected by two mechanisms: the emission of Gd3+ ions and the trapping of excited energy by the Eu3+ ions. The energy transfer between Eu3+ ions was also discussed in detail. This process leads to the enhancement of the luminescence bands originating from the 5D0 level. The dominant interaction between the Eu3+ ions in the energy transfer process is the dipole-dipole mechanism, which is determined by fitting the decay curve of the 5D2 level to the Inokuti-Hirayama model.

4.
Indian J Endocrinol Metab ; 27(1): 37-44, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37215277

RESUMO

Background: Papillary thyroid carcinoma (PTC) is more frequently reported in patients with Hashimoto's thyroiditis (HT), which may be associated with the presence of solid cell nests (SCNs) and focal PTC-like nuclear alterations in the thyroid gland. The point of this consideration was to assess the morphological and immunohistochemical features of SCNs and follicular epithelial changes in Vietnamese patients with HT. Materials and Methods: Hematoxylin-eosin and immunohistochemistry were performed on 20 samples of HT patients who underwent thyroidectomy and were diagnosed with Hashimoto's thyroiditis at Military Medical Hospital 103 from 6/2018 to 6/2019. The expression of five markers (P63, Calcitonin, TTF1, CK19 and HBME-1) in SCNs and follicular epithelial changes were evaluated. Results: Ninety per cent of samples had SCNs with an average of 10 SCNs per section. Only type 1 and type 4 SCNs were presented (85% and 55%, respectively) and all SCNs were composed of main cells (p63-positive). Fifteen of the 18 cases having SCNs possessed nuclear features of PTC. C-cell hyperplasia was found in one case with 20 clusters. All SCNs showed strong staining with CK19 and weak staining with HBME-1. Follicular epithelial changes were Hürthle cell metaplasia, PTC-like nuclear alterations, atypical solid nodules, papillary and glomerular-like forms (40%, 100%, 25% and 50%, respectively). Follicular cells of glomerular-like forms (new alteration) especially were positive with CK19 (2+ ~ 3+), HBME-1 (1+) and TTF1, while the components in these follicles were negative with CK19, HBME-1 and TTF1. Among PTC-like nuclear alterations, all the atypical solid nodules related to HT showed markers related to PTC and without SCNs. Conclusions: Increasing the number of SCNs, as well as PTC-like nuclear alterations of main cells in SCNs and follicular epithelial changes were co-expressed CK19 and HBME-1. Therefore, the need for HT management should be considered.

5.
Langmuir ; 39(18): 6637-6645, 2023 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-37116116

RESUMO

van der Waals heterostructures provide a powerful platform for engineering the electronic properties and for exploring exotic physical phenomena of two-dimensional materials. Here, we construct a graphene/BSe heterostructure and examine its electronic characteristics and the tunability of contact types under electric fields. Our results reveal that the graphene/BSe heterostructure is energetically, mechanically, and thermodynamically stable at room temperature. It forms a p-type Schottky contact and exhibits a high carrier mobility, making it a promising candidate for future Schottky field-effect transistors. Furthermore, applying an electric field not only reduces contact barriers but also induces a transition from a p-type to an n-type Schottky contact and from a Schottky to an ohmic contact, offering further potential for the control and manipulation of the heterostructure's electronic properties. Our findings offer a rational basis for the design of energy-efficient and tunable heterostructure devices based on the graphene/BSe heterostructure.

6.
Environ Sci Pollut Res Int ; 30(55): 117061-117081, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36701062

RESUMO

In this study, we use a time-varying parameter vector autoregression (TVP-VAR) in conjunction with the extended joint connectedness approach to examine the influences of the economic globalization measured by foreign direct investment (FDI) as well as trade openness (TO), on renewable and non-renewable energy consumption, by characterizing the connectedness of these variables, from 1987 to 2020 in Vietnam. Our results demonstrate that abolishing the state monopoly in foreign trade influences the system-wide dynamic connectedness of trade openness, which peaked in 1989. Net total directional connectedness of FDI and energy consumption suggests that both the consumption of renewable and non-renewable energy consistently act as net contagion shock receivers, and FDI is a critical net transmitter the whole time. Trade openness behaves consistently as a critical net shock transmitter in 1989 but turned into an essential net receiver from 1990 to 2020. In a system with trade openness, the consumption of non-renewable energy consistently acts as a net contagion shock receiver, and renewable energy consumption is a critical net transmitter in the whole sample. Pairwise connectedness reveals that FDI consistently appears as a shock transmitter to renewable and non-renewable energy consumption. Trade openness could be either a transmitter or a receiver of shock from non-renewable energy, depending on the period, and is a net receiver of shocks from renewable energy consumption during our sample. The findings of this paper are critical for Vietnam's government to make a greater contribution to the expansion of global commerce and a sustainable environment.


Assuntos
Dióxido de Carbono , Desenvolvimento Econômico , Vietnã , Dióxido de Carbono/análise , Internacionalidade , Investimentos em Saúde , Energia Renovável
7.
Glob Health Action ; 15(1): 2114616, 2022 12 31.
Artigo em Inglês | MEDLINE | ID: mdl-36174100

RESUMO

BACKGROUND: Smoking among adolescents in schools is a major global public health concern. There is limited evidence regarding prevalence and associated factors in Vietnam. OBJECTIVE: To compare the prevalence of smoking and associated factors among in-school adolescents aged 13-17 years in Vietnam between 2013 and 2019. METHODS: Data were collected from two rounds of the national representative Vietnam Global School-based Student Health Survey (GSHS) conducted in 2013 (n = 3,331) and 2019 (n = 7,690). Logistic regression was used to identify the factors associated with tobacco and electronic cigarette smoking among in-school adolescents. RESULTS: There was a significant reduction in the prevalence of current smoking (water pipes and cigarettes) from 5.4% (95% CI: 4.0-7.2) in 2013 to 2.8% (95% CI: 2.2-3.6) in 2019. In 2019, 2.6% of the in-school adolescents reported having used electronic cigarette products 30 days prior to the survey. Factors associated with a significantly higher likelihood of current smoking status included gender, loneliness, suicidal ideation, sexual activity, truancy, and alcohol consumption. Similar patterns were observed for e-cigarettes. CONCLUSION: Smoking among in-school adolescents in Vietnam decreased between 2013 and 2019. Follow-up studies are needed to further investigate causal factors so that future policies and communication programmes can be more effectively targeted to reduce smoking in adolescents.


Assuntos
Fumar Cigarros , Sistemas Eletrônicos de Liberação de Nicotina , Produtos do Tabaco , Adolescente , Fumar Cigarros/epidemiologia , Humanos , Prevalência , Nicotiana , Vietnã/epidemiologia
8.
J Colloid Interface Sci ; 599: 453-466, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33962206

RESUMO

During the past few decades, photoelectrochemical (PEC) water splitting has attracted significant attention because of the reduced production cost of hydrogen obtained by utilizing solar energy. Significant efforts have been invested by the scientific community to produce stable ternary metal oxide semiconductors, which can enhance the stability and increase the overall production of oxygen. Herein, we present the ternary metal oxide deposition of ZnCo2O4 as a route to obtain a novel photocatalyst layer on BiVO4 to form BiVO4/ZnCo2O4 a novel composite photoanode for PEC water splitting. The structural, topographical, and optical analyses were performed using field emission scanning electron microscopy, X-ray diffraction, high-resolution transmission electron microscopy, and UV-Vis spectroscopy to confirm the structure of the ZnCo2O4 grafted over BiVO4. A remarkable 4.4-fold enhancement of the photocurrent was observed for the BiVO4/ZnCo2O4 composite compared with bare BiVO4 under visible illumination. The optimum loading of ZnCo2O4 over BiVO4 yields unprecedented stable photocurrent density with an apparent cathodic shift of 0.46 V under 1.5 AM simulated light illumination. This is also evidenced by the flat-band potential change through Mott-Schottky analysis, which reveals the formation of p-ZnCo2O4 on n-BiVO4. The improvement in the PEC performance of the composite with respect to bare BiVO4 is ascribed to the formation of thin passivating layer of p-ZnCo2O4 on n-BiVO4 which improves the kinetics of interfacial charge transfer. Based on our study, we have gained an in-depth understanding of the BiVO4/ZnCo2O4 composite as high potential in efficient PEC water splitting devices.

9.
Parasitol Res ; 119(12): 4073-4088, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33068148

RESUMO

As a result of the experimental infection of rats with metacercariae of Paragonimus heterotremus Chen et Hsia, 1964 from crabs (Potamiscus tannanti) caught in Yen Bai province, Vietnam, it was found that worms migrated into the lungs, to the liver and less frequently to the tissue that lines body cavities of the hosts, where they reached the adult stage, but in the muscles, worms stayed at the larval stage. Studies have shown that for P. heterotremus, rats can simultaneously play the role of the final and paratenic host; herewith, an infection with the trematode of this species can lead to the development of three forms of paragonimiasis: pulmonary, hepatic and muscular. Eggs from the adult worms localised in the liver, unlike eggs from the adult worms localised in the lungs, were not excreted into the external environment, but accumulated inside the organ. Histology and description of changes, which take place on the external surface of organs affected with P. heterotremus, are given in this study. Based on the behavioural characteristics of worms during rat infection and molecular genetic data, we established that worms from Vietnam and India should be assigned to different species of Paragonimus. P. heterotremus distribution is limited to the territory of the Southeast China, Northern Vietnam, Laos and Thailand.


Assuntos
Fígado/parasitologia , Pulmão/parasitologia , Músculos/parasitologia , Paragonimíase/patologia , Paragonimus/classificação , Animais , Braquiúros/parasitologia , China , Índia , Laos , Metacercárias/patogenicidade , Paragonimus/genética , Paragonimus/patogenicidade , Ratos , Tailândia , Vietnã
10.
Parasit Vectors ; 11(1): 613, 2018 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-30497522

RESUMO

BACKGROUND: Due to the relative short life span and the limited spatial movement, porcine cysticercosis is an excellent indicator of current local active transmission. The aim of this study was to map at province-level, the occurrence of T. solium and T. asiatica in pigs and areas at risk of transmission to pigs in East and Southeast Asia, based on the density of extensive pig production systems and confirmed reports of porcine cysticercosis. METHODS: This study covered East and Southeast Asia, which consist of the following countries: Brunei, Cambodia, China, East Timor, Indonesia, Japan, Laos, Malaysia, Mongolia, Myanmar, North Korea, Philippines, Singapore, South Korea, Thailand and Vietnam. Literature searches were carried out to identify current epidemiological data on the occurrence of porcine cysticercosis caused by T. solium and T. asiatica infections. Modelled densities of pigs in extensive production systems were mapped and compared to available data on porcine cysticercosis. RESULTS: Porcine cysticercosis was confirmed to be present during the period 2000 to 2018 in eight out of the 16 countries included in this study. Taenia solium porcine cysticercosis was confirmed from all eight countries, whereas only one country (Laos) could confirm the presence of T. asiatica porcine cysticercosis. Province-level occurrence was identified in five countries (Cambodia, Indonesia, Laos, Myanmar, and Vietnam) across 19 provinces. Smallholder pig keeping is believed to be widely distributed throughout the region, with greater densities predicted to occur in areas of China, Myanmar, Philippines and Vietnam. CONCLUSIONS: The discrepancies between countries reporting taeniosis and the occurrence of porcine cysticercosis, both for T. solium and T. asiatica, suggests that both parasites are underreported. More epidemiological surveys are needed to determine the societal burden of both parasites. This study highlights a straightforward approach to determine areas at risk of porcine cysticercosis in the absence of prevalence data.


Assuntos
Cisticercose/parasitologia , Cisticercose/veterinária , Doenças dos Suínos/parasitologia , Taenia solium/isolamento & purificação , Taenia/isolamento & purificação , Animais , Sudeste Asiático/epidemiologia , Cisticercose/epidemiologia , Ásia Oriental/epidemiologia , Humanos , Suínos , Doenças dos Suínos/epidemiologia , Taenia/classificação , Taenia/genética , Taenia solium/classificação , Taenia solium/genética
12.
Zootaxa ; 4061(5): 483-503, 2016 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-27395515

RESUMO

A total of 12 chigger species (Acariformes: Trombiculidae) occurred on 7 bird species in Vietnam. Two new species, namely Neoschoengastia vietnamensis sp. nov. and Hypogastia stekolnikovi sp. nov. are described, figured and compared with similar species placed in relevant genera using differential diagnoses of related species. Figures and diagnosis of Leptotrombidium taiyuanense Tian and Wen, 1984 are added. Odontacarus audy (Radford, 1946), Leptotrombidium allosetum Wang, Liao and Lin, 1981, L. taiyuanense, Leptotrombidium hanseni Traub and Lakshana, 1966, Leptotrombidium kunshui Wen and Xiang, 1984, Leptotrombidium paradux Vercammen-Grandjean and Langston, 1976, Leptotrombidium turdicola Vercammen-Grandjean and Langston, 1976, Neotrombicula elegans Schluger, 1966 and Neoschoengastia longitar-salis Schluger and Belskaya, 1966 were recorded in Vietnam for the first time.


Assuntos
Doenças das Aves/parasitologia , Trombiculíase/veterinária , Trombiculidae/classificação , Distribuição Animal , Estruturas Animais/anatomia & histologia , Estruturas Animais/crescimento & desenvolvimento , Animais , Aves , Tamanho Corporal , Feminino , Masculino , Tamanho do Órgão , Trombiculíase/parasitologia , Trombiculidae/anatomia & histologia , Trombiculidae/crescimento & desenvolvimento , Vietnã
13.
Parasit Vectors ; 8: 21, 2015 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-25586313

RESUMO

BACKGROUND: Ninh Binh province is known as an endemic area of fish-borne zoonotic trematode (FZT) transmission in Vietnam. A cross-sectional study was conducted in Gia Minh and Gia Thinh communes of Gia Vien district, Ninh Binh province to investigate the infections with different stages of FZT in various host species. METHODS: Faecal samples from 1,857 humans were examined for trematode eggs using the Kato-Katz method, while faecal samples from 104 dogs, 100 cats, and 100 pigs were examined using the Formalin-ethyl acetate concentration technique (FECT). A total of 483 specimens of freshwater fish, representing 9 species, were examined for metacercariae using the artificial digestion method. Three methods of cercarial detection (shedding, crushing and cutting) were applied for examination of 3,972 specimens of freshwater snails, representing 7 species. All relevant data e.g. location, sex, age group, animal species, and habitat were recorded for statistical analyses. RESULTS: Helminth eggs were found in 65.5% of the human faecal samples, including 20.5% of faecal samples containing small trematode eggs. Infection with small trematodes differed among communes, age groups and sexes. Eggs of small trematodes were found in 32.7% of faecal samples from dogs, 49.0% from cats and 13.0% from pigs. The difference in prevalences and intensities were significant among species of animals but did not differ between the two communes. All fish species were infected with FZT, with an average prevalence of 56.1% and a mean intensity of 33.245 metacercariae per gram. Prevalence and intensity in fish differed significantly among cummunes and fish groups. Six species of zoonotic trematodes were identified. Metacercariae of the small liver fluke, Clonorchis sinensis, was only found in Hemiculter leucisculus. A total of 9 specimens from two snail species, Melanoides tuberculata and Bithynia fuchsiana, were infected with trematodes and four cercarial types were detected in the study sites. CONCLUSIONS: We conclude that Gia Minh and Gia Thinh communes are continuing to be hot-spot endemic areas of FZT and other helminths infections where the habit of eating raw fish by the local people is still present.


Assuntos
Peixes/parasitologia , Doenças Transmitidas por Alimentos/parasitologia , Infecções por Trematódeos/veterinária , Adolescente , Adulto , Animais , Doenças do Gato/epidemiologia , Doenças do Gato/parasitologia , Gatos , Doenças do Cão/epidemiologia , Doenças do Cão/parasitologia , Cães , Fezes/parasitologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Caramujos , Suínos , Doenças dos Suínos/epidemiologia , Doenças dos Suínos/parasitologia , Infecções por Trematódeos/epidemiologia , Infecções por Trematódeos/parasitologia , Vietnã/epidemiologia , Adulto Jovem , Zoonoses
14.
Int J Parasitol ; 44(11): 795-810, 2014 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-25123068

RESUMO

Clonorchiasis is a parasitic disease of high public health importance in many countries in southeastern Asia and is caused by the Chinese liver fluke Clonorchis sinensis. However, the genetic structure and demographic history of its populations has not been sufficiently studied throughout the geographic range of the species and available data are based mainly on partial gene sequencing. In this study, we explored the genetic diversity of the complete 1560 bp cytochrome c oxidase subunit 1 (cox1) gene sequence for geographically isolated C. sinensis populations in Russia and Vietnam, to our knowledge for the first time. The results demonstrated low nucleotide and high haplotype differentiation within and between the two compared regions and a clear geographical vector for the distribution of genetic diversity patterns among the studied populations. These results suggest a deep local adaptation of the parasite to its environment including intermediate hosts and the existence of gene flow across the species' range. Additionally, we have predicted an amino acid substitution in the functional site of the COX1 protein among the Vietnamese populations, which were reported to be difficult to treat with praziquantel. The haplotype networks consisted of several region-specific phylogenetic lineages, the formation of which could have occurred during the most extensive penultimate glaciations in the Pleistocene Epoch. The patterns of genetic diversity and demographics are consistent with population growth of the liver fluke in the late Pleistocene following the Last Glacial Maximum, indicating the lack of a population bottleneck during the recent past in the species' history. The data obtained have important implications for understanding the phylogeography of C. sinensis, its host-parasite interactions, the ability of this parasite to evolve drug resistance, and the epidemiology of clonorchiasis under global climate change.


Assuntos
Clonorquíase/parasitologia , Clonorchis sinensis/genética , Variação Genética , Animais , Sequência de Bases , Clonorquíase/epidemiologia , DNA de Helmintos/genética , Masculino , Filogenia , Ratos , Ratos Sprague-Dawley , Federação Russa/epidemiologia , Vietnã/epidemiologia
15.
Zootaxa ; 3755: 419-33, 2014 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-24869830

RESUMO

A total of 239 individuals of 50 bird species were examined for chewing lice (Insecta: Phthiraptera) in southern Vietnam. Fifty-six birds of 20 species were parasitised by 15 species of lice belonging to 10 genera from two suborders, Amblycera: Menacanthus, Meromenopon, Myrsidea, and Ischnocera: Alcedoecus, Brueelia, Cuculicola, Meropoecus, Penenirmus, Philopteroides and Philopterus. Thirteen louse samples from Passeriformes were identified to genus only because they contain inadequate material. A total of 29 host-louse associations were found, of which nine are new, including: (1) two new species of the genus Brueelia, which are described and named in this paper: Brueelia binhchauensis from Megalaima lineata (Vieillot, 1816) (Piciformes: Megalaimidae), and Brueelia malacocincla from Malacocincla abbotti Blyth, 1845 (Passeriformes: Pellorneidae); (2) first records of lice from Cyornis hainanus (Ogilvie-Grant, 1900); and (3) the first record of Myrsidea claytoni Hellenthal & Price, 2003 from Cymbirhynchus macrorhynchos (Gmelin, 1788) (Passeriformes: Eurylaimidae), here regarded as a case of natural host-switching. A portion of the mitochondrial cytochrome oxidase I (COI) gene for some species of chewing lice was sequenced in order to assess their genetic divergences.


Assuntos
Amblíceros/anatomia & histologia , Amblíceros/classificação , Doenças das Aves/parasitologia , Iscnóceros/anatomia & histologia , Iscnóceros/classificação , Infestações por Piolhos/veterinária , Amblíceros/fisiologia , Animais , Doenças das Aves/epidemiologia , Aves , Demografia , Feminino , Iscnóceros/fisiologia , Infestações por Piolhos/epidemiologia , Infestações por Piolhos/parasitologia , Masculino , Especificidade da Espécie , Vietnã/epidemiologia
16.
J Parasitol ; 100(3): 280-3, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24393023

RESUMO

Thirty-two black-and-red broadbill Cymbirhynchus macrorhynchos were examined for chewing lice in Vietnam. All birds examined were parasitized by Myrsidea claytoni. Mean abundance was 27.3, with intensity range 5-80 lice per bird. This is the first report of a Myrsidea from this host, although the females differ slightly from the original description of M. claytoni from Pycnonotus eutilotus in the shape of metanotum and of tergites I-II. So this is also the first record of 1 species of Myrsidea from 2 very distantly related hosts. Although the original hosts of M. claytoni belong to the family Pycnonotidae, C. macrorhynchos is a member of the family Eurylaimidae, representing the Old World Suboscines, which are considered as a basal lineage among passerines. Therefore, our record represents an interesting case of natural host switching. The high prevalence as well as the intensity of infestation show that M. claytoni is well established on C. macrorhynchos in Vietnam.


Assuntos
Amblíceros/classificação , Doenças das Aves/parasitologia , Infestações por Piolhos/veterinária , Passeriformes/parasitologia , Amblíceros/anatomia & histologia , Amblíceros/crescimento & desenvolvimento , Animais , Doenças das Aves/epidemiologia , Feminino , Infestações por Piolhos/epidemiologia , Infestações por Piolhos/parasitologia , Masculino , Prevalência , Razão de Masculinidade , Vietnã/epidemiologia
17.
Am J Trop Med Hyg ; 89(4): 721-723, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23980132

RESUMO

We have modified an existing semi-nested multiplex polymerase chain reaction (PCR) by adding one Plasmodium knowlesi-specific nested PCR, and validated the latter against laboratory and clinical samples. This new method has the advantage of being relatively affordable in low resource settings while identifying the five human Plasmodium species with a three-step PCR.


Assuntos
Malária/parasitologia , Plasmodium/classificação , Plasmodium/isolamento & purificação , Reação em Cadeia da Polimerase/métodos , Animais , Sudeste Asiático/epidemiologia , Humanos , Malária/epidemiologia
18.
Acta Parasitol ; 58(3): 231-58, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23990419

RESUMO

Fishborne zoonotic trematodes (FZT), infecting humans and mammals worldwide, are reviewed and options for control discussed. Fifty nine species belonging to 4 families, i.e. Opisthorchiidae (12 species), Echinostomatidae (10 species), Heterophyidae (36 species) and Nanophyetidae (1 species) are listed. Some trematodes, which are highly pathogenic for humans such as Clonorchis sinensis, Opisthorchis viverrini, O. felineus are discussed in detail, i.e. infection status in humans in endemic areas, clinical aspects, symptoms and pathology of disease caused by these flukes. Other liver fluke species of the Opisthorchiidae are briefly mentioned with information about their infection rate and geographical distribution. Intestinal flukes are reviewed at the family level. We also present information on the first and second intermediate hosts as well as on reservoir hosts and on habits of human eating raw or undercooked fish.


Assuntos
Doenças dos Peixes/epidemiologia , Doenças dos Peixes/transmissão , Infecções por Trematódeos/epidemiologia , Infecções por Trematódeos/veterinária , Zoonoses/epidemiologia , Zoonoses/transmissão , Animais , Doenças dos Peixes/parasitologia , Peixes , Humanos , Topografia Médica , Infecções por Trematódeos/parasitologia , Infecções por Trematódeos/transmissão , Zoonoses/parasitologia
19.
PLoS One ; 8(3): e58205, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23536790

RESUMO

BACKGROUND: Despite much success in reducing the burden of malaria in Vietnam, pockets of malaria persist and eliminating them remains an important development goal. In central Vietnam, insecticide-treated hammocks have recently been introduced to help counter the disease in the highly forested, mountainous areas, where other measures have so far been unsuccessful. This study assesses the cost-effectiveness of using long-lasting insecticide-treated hammocks in this area. METHODS AND FINDINGS: This cost-effectiveness study was run alongside a randomized control trial testing the efficacy of the long-lasting insecticide-treated hammocks. Data were collected through an exit survey, a household survey, expenditure records and key informant interviews. The study estimates that under normal (non-trial) conditions the total net societal cost per malaria episode averted in using long-lasting insecticide-treated hammocks in this area was 126 USD. Cost per hammock, including insecticidal netting, sewing, transport, and distribution was found to be approximately 11.76 USD per hammock. Average savings per episode averted were estimated to be $14.60 USD for the health system and 14.37 USD for households (including both direct and indirect cost savings). The study estimates that the annual financial outlay required of government to implement this type of programme to be 3.40 USD per person covered per year. CONCLUSION: The study finds that the use of a hammock intervention could represent good value for money to help prevent malaria in more remote areas, where traditional control measures such as insecticide-treated bednets and indoor residual spraying are insufficient or inappropriate to control malaria. However, the life span of the hammock-the number of years over which it effectively deters mosquitoes-has a significant impact on the cost-effectiveness of the intervention and study results should be interpreted in light of the evidence on effectiveness gathered in the years to come.


Assuntos
Inseticidas/economia , Malária/economia , Malária/prevenção & controle , Controle de Mosquitos/economia , Leitos , Análise Custo-Benefício , Humanos , Vietnã
20.
J Parasitol ; 95(3): 629-33, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19642804

RESUMO

Recent studies in Vietnam and other Asian countries have shown that fish-borne zoonotic intestinal trematodes (FZT) occur very frequently in humans. The dominant intestinal FZT in Vietnamese fish are species of Haplorchis, in particular H. pumilio. However, basic studies on the biology and pathology of adult H. pumilio are difficult because of the lack of a standardized experimental animal model. The objective of this study was to establish and optimize such an animal-infection model for H. pumilio. Using metacercariae isolated from naturally infected fish, experiments were conducted to identify a suitable experimental animal host species, as well as the optimum metacercariae infection dose, and to determine the post-infection interval for patency. In a series of experiments, mice (Mus musculus) and chickens (Gallus gallus dom.) were infected with different numbers of metacercariae, and worm recoveries were made at varying intervals post-infection (PI). Based on the mean number of adult flukes recovered/number of metacercariae inoculated and the percent of hosts infected, mice were significantly more susceptible to infection than were chickens. The proportion of metacercariae developing to the adult stage increased with dose size. The peak worm recovery (geometric mean) was found to be day 7, although not all recovered flukes were gravid until day 9 PI. These results describe a mouse infection model with good predictability for intestinal flukes, such as H. pumilio, results which could facilitate investigations on important biological and pathological aspects of intestinal fluke infections.


Assuntos
Modelos Animais de Doenças , Suscetibilidade a Doenças , Doenças dos Peixes/parasitologia , Heterophyidae/isolamento & purificação , Infecções por Trematódeos/parasitologia , Análise de Variância , Animais , Carpas , Galinhas , Doenças dos Peixes/transmissão , Heterophyidae/imunologia , Heterophyidae/patogenicidade , Interações Hospedeiro-Parasita , Intestino Delgado/parasitologia , Camundongos , Fatores de Tempo , Infecções por Trematódeos/imunologia , Infecções por Trematódeos/transmissão , Zoonoses
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