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1.
Exp Parasitol ; 183: 178-181, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28916459

RESUMO

Free-living amoebae (FLA) are protozoa that are widely distributed in the environment mainly in water and soil related habitats. These amoebae have also been reported to be associated with some bacterial pathogens for humans such as Campylobacter spp. The species C. jejuni is the causative agent of about 90% of human campylobacteriosis cases worldwide and this disease may even end up in severe autoimmune sequelae as Guillain-Barré syndrome (GBS). In this study, the interactions between the strain Acanthamoeba castellanii Neff and Campylobacter jejuni was investigated. Campylobacter jejuni was coincubated with Acanthamoeba castellanii Neff trophozoites at different temperatures, in order to evaluate the C. jejuni ability to grow in presence A. castellanii culture and Acanthamoeba Conditioned Medium (ACM). C. jejuni was coincubated with A. castellanii axenic culture at different temperatures in aerobic conditions. Our results revealed that bacteria were still cultivable (Blood Agar medium, at 37 °C, in microaerophilic atmosphere) after a 14 days C. jejuni - A. castellanii coculture, comparing with C. jejuni alone, which was only cultivable for 24 h.


Assuntos
Acanthamoeba castellanii/fisiologia , Campylobacter jejuni/crescimento & desenvolvimento , Acanthamoeba castellanii/efeitos dos fármacos , Acanthamoeba castellanii/crescimento & desenvolvimento , Aerobiose , Animais , Antibacterianos/farmacologia , Campylobacter jejuni/efeitos dos fármacos , Campylobacter jejuni/fisiologia , Técnicas de Cocultura , Gentamicinas/farmacologia , Humanos , Temperatura
2.
Exp Parasitol ; 183: 167-170, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28917709

RESUMO

Free-living amoebae (FLA) are opportunistic protozoa widely distributed in the environment. They are frequently found in water and soil samples, but they have also been reported to be associated with bacterial human pathogens such as Legionella spp. Campylobacter spp or Vibrio cholerae among others. Including within Vibrio spp. V. harveyi (Johnson and Shunk, 1936) is a bioluminescent marine bacteria which has been found swimming freely in tropical marine waters, being part of the stomach and intestine microflora of marine animals, and as both a primary and opportunistic pathogen of marine animals. Our aim was to study the interactions between Vibrio harveyi and Acanthamoeba castellanii Neff. Firstly, in order to analyze changes in it cultivability, V. harveyi was coincubated with A. castellanii Neff axenic culture and with Acanthamoeba Conditioned Medium (ACM) at different temperatures in aerobic conditions. Interestingly, at 4 °C and 18-20 °C bacteria were still cultivable in marine agar, at 28 °C, in aerobic conditions, but there weren't significant differences comparing with the controls. We also noted an enhanced migration of Acanthamoeba toward V. harveyi on non-nutrient agar plates compared to controls with no bacteria.


Assuntos
Acanthamoeba castellanii/fisiologia , Vibrio/fisiologia , Acanthamoeba castellanii/crescimento & desenvolvimento , Antibacterianos/farmacologia , Aquicultura , Técnicas de Cocultura , Testes de Sensibilidade Microbiana , Movimento , Vibrio/efeitos dos fármacos , Vibrio/crescimento & desenvolvimento
3.
Curr Microbiol ; 73(1): 104-7, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27056561

RESUMO

Free-living amoebae (FLA) are widely distributed protozoa in the environment and have been isolated from many sources such as dust, soil and water. Furthermore, some genera/species of FLA such as Naegleria fowleri, Balamuthia mandrillaris and Acanthamoeba spp. are also able to cause opportunistic infections in humans and other animals. More recently, FLA have been reported to be environmental carriers of pathogenic bacteria, fungi and viruses, and thus have gained further importance from the public health point of view. Among them, Acanthamoeba spp. and Vermamoeba vermiformis have been described in many occasions as the most common carriers of pathogens of high medical relevance such as Legionella pneumophila and Mycobacterium spp. In this study, 24 soil samples were collected from the island of El Hierro, Canary Islands, Spain, in order to check for the presence of V. vermiformis strains in these samples. Soil samples were cultured on 2 % non-nutrient agar plates covered with a thin layer of heat-killed E. coli and checked daily for the presence of Vermamoeba. After a week, V. vermiformis amoebae were observed in 5 of the 24 processed samples (20.8 %) incubated at room temperature and 37 °C. Molecular characterization was carried out by amplifying the 18S rDNA gene and DNA sequencing, confirming that the isolated strains belonged to Vermamoeba vermiformis species. The high percentage of V. vermiformis in the studied soil sources should raise awareness in the region since these amoebae are potential environmental carriers of pathogens of high medical relevance.


Assuntos
Amoeba/genética , Amoeba/isolamento & purificação , Solo/parasitologia , Amoeba/fisiologia , DNA de Protozoário/genética , Ilhas , Espanha
4.
Parasitol Res ; 115(8): 2953-6, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27075307

RESUMO

The genus Acanthamoeba includes pathogenic strains which are causative agents of keratitis and encephalitis that often may end fatal in humans and other animals. In the present study, forty soil samples were collected in the island of El Hierro, Canary Islands, Spain, and checked for the presence of Acanthamoeba. Samples were cultivated onto 2 % non-nutrient agar plates seeded with a layer of heat killed Escherichia coli. Amplification by PCR and sequencing of the DF3 region of the 18S rDNA of Acanthamoeba was carried out in order to confirm morphological identification of the amoebae. Furthermore, Acanthamoeba spp. was isolated from 47.5 % of soil samples. Moreover, genotypes T2, T4, and T11 were identified in these samples. To the best of our knowledge, this is the first study to establish genotypes T2, T4, and T11 in soil sources from El Hierro island.


Assuntos
Acanthamoeba/isolamento & purificação , Solo/parasitologia , Acanthamoeba/genética , Amoeba/genética , Animais , DNA de Protozoário , DNA Ribossômico/genética , Genótipo , Humanos , Reação em Cadeia da Polimerase , Espanha
5.
Antimicrob Agents Chemother ; 59(5): 2817-24, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25733513

RESUMO

Members of the genus Acanthamoeba are facultative pathogens of humans, causing a sight-threatening keratitis and a life-threatening encephalitis. In order to treat those infections properly, it is necessary to target the treatment not only to the trophozoite but also to the cyst. Furthermore, it may be advantageous to avoid parasite killing by necrosis, which may induce local inflammation. We must also avoid toxicity of host tissue. Many drugs which target eukaryotes are known to induce programmed cell death (PCD), but this process is poorly characterized in Acanthamoeba. Here, we study the processes of programmed cell death in Acanthamoeba, induced by several drugs, such as statins and voriconazole. We tested atorvastatin, fluvastatin, simvastatin, and voriconazole at the 50% inhibitory concentrations (IC50s) and IC90s that we have previously established. In order to evaluate this phenomenon, we investigated the DNA fragmentation, one of the main characteristics of PCD, with quantitative and qualitative techniques. Also, the changes related to phosphatidylserine exposure on the external cell membrane and cell permeability were studied. Finally, because caspases are key to PCD pathways, caspase activity was evaluated in Acanthamoeba. All the drugs assayed in this study induced PCD in Acanthamoeba. To the best of our knowledge, this is the first study where PCD induced by drugs is described quantitatively and qualitatively in Acanthamoeba.


Assuntos
Acanthamoeba castellanii/efeitos dos fármacos , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Voriconazol/farmacologia , Ácidos Graxos Monoinsaturados/farmacologia , Fluvastatina , Indóis/farmacologia , Concentração Inibidora 50 , Sinvastatina/farmacologia
6.
Arch Microbiol ; 197(5): 639-43, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25716077

RESUMO

The present study describes two cases of Acanthamoeba infections (keratitis and ascites/peritonitis) in small breed domestic dogs in Tenerife, Canary Islands, Spain. In both cases, amoebic trophozoites were observed under the inverted microscope and isolated from the infected tissues and/or fluids, without detecting the presence of other viral, fungal or bacterial pathogens. Amoebae were isolated using 2 % non-nutrient agar plates and axenified for further biochemical and molecular analyses. Osmotolerance and thermotolerance assays revealed that both isolates were able to grow up to 37 °C and 1 M of mannitol and were thus considered as potentially pathogenic. Moreover, the strains were classified as highly cytotoxic as they cause more than 75 % of toxicity when incubated with two eukaryotic cell lines. In order to classify the strains at the molecular level, the diagnostic fragment 3 (DF3) region of the 18S rDNA of Acanthamoeba was amplified and sequenced, revealing that both isolates belonged to genotype T4. In both cases, owners of the animals did not allow any further studies or follow-up and therefore the current status of these animals is unknown. Furthermore, the isolation of these pathogenic amoebae should raise awareness with the veterinary community locally and worldwide.


Assuntos
Acanthamoeba/isolamento & purificação , Amebíase/diagnóstico , Amebíase/veterinária , Doenças do Cão/diagnóstico , Doenças do Cão/parasitologia , Cães/parasitologia , Acanthamoeba/classificação , Acanthamoeba/genética , Amebíase/parasitologia , Animais , Ascite/diagnóstico , Ascite/parasitologia , Ascite/veterinária , Sequência de Bases , DNA Ribossômico/genética , Genes de RNAr , Genótipo , Ceratite/diagnóstico , Ceratite/parasitologia , Ceratite/veterinária , Peritonite/diagnóstico , Peritonite/parasitologia , Peritonite/veterinária , Espanha
7.
J Eukaryot Microbiol ; 62(3): 416-21, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25393552

RESUMO

Acanthamoeba spp. are opportunistic pathogens that are ubiquitous in nature. Many species of this genus are responsible for a fatal encephalitis and keratitis in humans and other animals. Seventy-two soil samples were collected from the parishes across Jamaica and assessed for the presence of Acanthamoeba spp. Cultivation was carried out on non-nutrient agar plates seeded with heat killed Escherichia coli. PCR and sequencing of the DF3 region were carried out in order to genotype the isolated strains of Acanthamoeba. Thermotolerance and osmotolerance assays were utilized to investigate the pathogenic potential of the Acanthamoeba isolates. Acanthamoeba spp. was isolated from 63.9% of soil samples. Sequencing of the DF3 region of the 18S rDNA resulted in the identification of genotypes T4, T5, and T11. T4 genotype was most frequently isolated. Most isolates were thermotolerant or both thermotolerant and osmotolerant, indicating that they may present the potential to cause disease in humans and other animals.


Assuntos
Acanthamoeba/classificação , Acanthamoeba/isolamento & purificação , Genótipo , Solo/parasitologia , Acanthamoeba/genética , Acanthamoeba/crescimento & desenvolvimento , Análise por Conglomerados , DNA Ribossômico/química , DNA Ribossômico/genética , Temperatura Alta , Jamaica , Dados de Sequência Molecular , Pressão Osmótica , Filogenia , RNA Ribossômico 18S/genética , Análise de Sequência de DNA
8.
Curr Microbiol ; 70(5): 685-9, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25578177

RESUMO

Helicobacter pylori is considered to be responsible for the most common gastric infections in humans worldwide. In animals, other Helicobacter species are linked to gastritis with and without the presence of ulcers in their respective hosts. Moreover, gastric ulcers have been reported for decades in wild and captive dolphins. Clinical signs include lack of appetite, anorexia, abdominal tenderness, depression, and occasional unresponsiveness. In this study, serum and stool of nine bottlenose dolphins from Loro Parque collection Tenerife, Spain were examined for the presence of Helicobacter spp. The aim of our study was to evaluate the use of two commercially available kits for the detection of H. pylori in humans: a stool antigen immunoassay (Letitest H. pylori CARD) and a Western blot assay (EUROLINE-WB H. pylori) that were adapted to identify specific Helicobacter spp. antibodies in the tested Loro Parque bottlenose dolphin collection. The utility of these diagnostic kits for their application in dolphins is demonstrated, and their use in the future for the diagnosis of Helicobacter spp. in both wild and captive dolphins is proposed in this study.


Assuntos
Anticorpos Antibacterianos/sangue , Antígenos de Bactérias/análise , Técnicas Bacteriológicas/métodos , Golfinho Nariz-de-Garrafa/microbiologia , Infecções por Helicobacter/veterinária , Helicobacter/isolamento & purificação , Kit de Reagentes para Diagnóstico , Animais , Fezes/microbiologia , Helicobacter/imunologia , Infecções por Helicobacter/diagnóstico , Infecções por Helicobacter/microbiologia , Imunoensaio/métodos , Soro/química , Espanha , Medicina Veterinária/métodos
9.
J Water Health ; 13(3): 909-19, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26322776

RESUMO

Free living amoebae (FLA) are amphizoic protozoa that are ubiquitous in nature. Infection with FLA may result in neurological, ocular and skin infections. Exposure to Acanthamoeba occurs frequently through water contact and knowledge of the presence of the organisms in water sources is important in understanding transmission dynamics. The distribution of Acanthamoeba was studied in recreational and domestic water samples collected from across Jamaica. Morphological assessment and polymerase chain reaction revealed Acanthamoeba spp. isolates in 50.6% (42/83) and 17.3% (14/81) of recreational and domestic water, respectively. Sequencing of the DF3 region of the 18S rDNA resulted in the identification of genotypes T3, T4, T5, T10 and T11 corresponding to Acanthamoeba spp: A. griffini, A. triangularis, A. lenticulata, A. culbertsoni and A. hatchetti. Moreover, T4 was the most frequently isolated genotype in both recreational and domestic water. Thermotolerance and osmotolerance assays indicated that most isolates were potentially pathogenic. This is the first report of T3 and T10 genotypes in the Caribbean and the first report of these Acanthamoeba spp. in Jamaican waters. The study shows that there is potential risk of infection to contact wearers who practise poor lens care. Further, Acanthamoeba should be considered as a cause of neurological infections in Jamaica.


Assuntos
Acanthamoeba/genética , Acanthamoeba/isolamento & purificação , Água Doce/parasitologia , Nascentes Naturais/parasitologia , Praias , Lentes de Contato , Genótipo , Humanos , Jamaica , Medição de Risco , Água do Mar/parasitologia
10.
Arch Microbiol ; 196(11): 785-90, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25064337

RESUMO

Erysipelothrix rhusiopathiae is the causative agent of erysipelas, a disease of many mammalian and avian species, mainly swine and turkeys. In cetaceans, erysipelas is considered to be the most common infection in juvenile individuals, which have not been vaccinated. Moreover, the disease manifest in both forms, the dermatologic and the acute septicemic forms, has been reported in various species of dolphins and whales. It is difficult to diagnose erysipelas by currently available approaches. Moreover, it is mainly based on culture methods and also PCR methods, which are currently being developed. At the present stage, prophylactic approaches are based on antibiotic therapy and vaccination mostly with porcine erysipelas vaccines. In the present study, an Indirect Immuno Fluorescence method for the detection of dolphin antibodies levels against E. rhusiopathiae was developed and applied in two different groups of captive bottlenose dolphins (Tursiops truncatus) from Loro Parque (Tenerife, Canary Islands, Spain) and L'Oceanogràfic de Valencia (Valencia, Spain) in order to check the tittering levels of antibodies after application of porcine erysipelas vaccines in the studied dolphins.


Assuntos
Animais de Zoológico , Anticorpos Antibacterianos/sangue , Golfinho Nariz-de-Garrafa , Infecções por Erysipelothrix/imunologia , Erysipelothrix/imunologia , Técnica Indireta de Fluorescência para Anticorpo/veterinária , Animais , Vacinas Bacterianas/imunologia , Infecções por Erysipelothrix/diagnóstico , Feminino , Masculino , Espanha , Vacinação/veterinária
11.
Parasitol Res ; 113(11): 4117-22, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25134946

RESUMO

Free living amoebae (FLA) are ubiquitous protozoa, which may behave as parasites under certain conditions. Four genera are recognized as causal agents of infections in humans and animals: Naegleria, Sappinia, Acanthamoeba and Balamuthia. This work determines the presence of FLA in combination shower units and employs molecular biology for the characterization of isolates. The morphological analysis and partial sequencing of the 18S rDNA gene revealed the presence of Acanthamoeba genotype T4 in 30% of the units sampled. In addition to Acanthamoeba cysts, trophozoites with morphological characteristics similar to Balamuthia were identified. PCR assay using the mitochondrial 16S rRNA gene as a target confirmed the identification of the amoeba as Balamuthia mandrillaris. Up to date, this is the first report of the isolation of B. mandrillaris in Central America and the fifth report worldwide.


Assuntos
Acanthamoeba/isolamento & purificação , Balamuthia mandrillaris/isolamento & purificação , Água Doce/parasitologia , Abastecimento de Água , Acanthamoeba/genética , Balamuthia mandrillaris/genética , Costa Rica , DNA de Protozoário/genética , Humanos , RNA Ribossômico 16S/genética , Trofozoítos
12.
Parasitol Res ; 113(7): 2509-13, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24781021

RESUMO

Balamuthia mandrillaris is an opportunistic free-living amoeba that has been reported to cause skin lesions and the fatal Balamuthia amoebic encephalitis (BAE) in humans and other animals. Currently, around 200 human BAE cases have been reported worldwide, although this number is considered to be underestimated. The highest number of BAE cases has been reported in the American continent, mainly in the southwest of the USA. Peru seems to be another hotspot for BAE with around 55 human cases having been identified, usually involving cutaneous infection, especially lesions in the central face area. The isolation of Balamuthia from environmental sources has been reported on only three prior occasions, twice from Californian soils and once from dust in Iran and so it seems that this amoeba is relatively rarely encountered in samples from the environment. We investigated that possibility of finding the amoebae in soil samples from different regions where clinical cases have been reported in Peru. Twenty-one samples were cultured in non-nutrient agar plates and were checked for the presence of B. mandrillaris-like trophozoites and/or cysts. Those samples that were positive for these amoebae by microscopic criteria were then confirmed by PCR amplification and DNA sequencing of the mitochondrial 16S rDNA gene of B. mandrillaris. We have detected the presence of B. mandrillaris in four samples collected in the regions of Piura (3) and Lima (1) where infection cases have been previously reported. We hypothesize that B. mandrillaris is present in Peru in soil and dust which therefore constitutes a source of the infection for the BAE cases previously reported in this country. Further studies should be carried out in the area to confirm the generality of this finding.


Assuntos
Balamuthia mandrillaris/isolamento & purificação , RNA de Protozoário/genética , RNA Ribossômico 16S/genética , Solo/parasitologia , Amebíase/epidemiologia , Amebíase/parasitologia , Animais , Balamuthia mandrillaris/genética , Humanos , Peru/epidemiologia , Análise de Sequência de DNA
13.
Parasitol Res ; 113(2): 451-5, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24221890

RESUMO

The diagnosis of toxoplasmosis is often complicated by the lack of specific clinical symptoms or postmortem features, in humans and other animals. The only diagnostic test described so far for the serological diagnosis of Toxoplasma gondii in marine mammals is the modified agglutination test (Dubey et al., Am J Vet Res 48(8):1239-1243, 1987). The development of more sensible and specific immunological techniques requires specific antibodies, which are currently unavailable in the scientific market. Indirect immunofluorescence (IIF) is one of the most widely used methods for the diagnosis of toxoplasmosis in humans (Auer et al., Parasitol Res 12:965-970, 2000). In order to develop and apply this technique to the bottlenose dolphin (Tursiops truncatus), immunoglobulins were firstly purified using ion-exchange chromatography. The purified immunoglobulins were then injected in New Zealand rabbits in order to obtain polyclonal antibodies. These antisera were validated by the IIF technique, using as controls serum samples of dolphins infected by Toxoplasma. The results were visualized using antirabbit IgG labeled with fluorescein. This newly developed and specific serological assay was then tested with the dolphin collection of Loro Parque, Tenerife, Spain (group I), and L'Oceanogràfic of Valencia, Spain (group II). The obtained results in this study showed that none of the dolphins from group 1 were infected by T. gondii and two animals were positive in group 2. Furthermore, we conclude that this study has produced antibodies with high specificity against dolphin immunoglobulins and an IIF method which may be used as immunological diagnostic tools, especially for the serological diagnosis of toxoplasmosis.


Assuntos
Anticorpos Antiprotozoários/sangue , Golfinho Nariz-de-Garrafa/parasitologia , Técnica Indireta de Fluorescência para Anticorpo , Toxoplasma/imunologia , Toxoplasmose Animal/diagnóstico , Testes de Aglutinação , Animais , Golfinho Nariz-de-Garrafa/imunologia , Cromatografia por Troca Iônica , Coelhos , Espanha , Toxoplasmose Animal/imunologia
14.
Anemia ; 2024: 1687917, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39228691

RESUMO

Sickle cell anemia (SCA) results from a mutation in the ß-globin gene, leading to the production of mutant hemoglobin, known as hemoglobin S (HbS). Despite being a genetic disorder, the phenotype of SCA can be influenced by the level of fetal hemoglobin (HbF), which is associated with beta S-globin haplotypes. In this study, we conducted newborn screening (NBS) using samples collected from umbilical cord blood in two hospitals on Santiago Island, Cape Verde. In newborns, HbS was detected using high-performance liquid chromatography (HPLC) on dried blood spot, with confirmation through polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP). In addition, we assessed the hematological and clinical characteristics of a second population group consisting of patients diagnosed with SCA. Haplotype determination was performed on both newborns with HbS and patients with SCA. Beta S-globin haplotypes were determined using PCR-RFLP. Hematological values were analyzed using standard methods. Out of 346 newborns, 21 (6%) were carriers of the sickle cell trait (HbAS) while none were identified as homozygous for sickle cell disease (HbSS). Among both groups of individuals, four haplotypes were identified: Senegal, Arabi-Indian, Bantu, and Benin. The Senegal haplotype was the most prevalent, possibly reflecting the ethnic origin of the mutations observed. Hematological values did not differ significantly among haplotypes. However, higher levels of HbF were associated with better hematological values. These findings suggest a positive impact of elevated HbF levels on reducing the severity of SCA. Finally, we demonstrated how the combination of technics, HPLC and molecular analysis, provided a consistent and reproducible results that can be used for NBS for SCA.

15.
Farm Comunitarios ; 16(2): 14-28, 2024 Apr 15.
Artigo em Espanhol | MEDLINE | ID: mdl-39156028

RESUMO

Introduction: Perception and relief of pain exhibit variability among individuals. Age, gender, ethnicity, educational level, actual stress level, mood, or medical conditions can modify the personal interpretation of pain and responses to pharmacological treatment. These differences may play a significant role in the effects, sometimes unwanted, of analgesic treatment. Objectives: Define patient typologies with Failed Back Syndrome regarding attitudes toward the disease, treatment, healthcare, and the follow-up they receive from their healthcare professionals. Create a tool for patient profile identification. Materials and Methods: A clinical case series study, observational, descriptive, and cross-sectional. Study population: patients from the Pain Unit of Nuestra Señora de La Candelaria University Hospital (HUNSC) in Tenerife, conducted in three phases: collection of medical history data (F0), initial visit (F1), and personal interview (F2). Results: Five patient typologies are obtained based on responses to 17 items. Regression equations are calculated from these responses to predict the patient type. They are grouped into "Classics," "Dependents," "Critics," "Unconscious," and "Responsible." Additionally, two tools with 17 items and another with 7 optimized items are developed to simplify the process. Conclusions: These tools enable Community Pharmacy (CP) to identify patients based on their characteristics to direct personalized strategies for each of them.

16.
Malar J ; 12: 435, 2013 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-24289142

RESUMO

BACKGROUND: Knowledge of appropriate reference intervals is critical not only to provide optimal clinical care, but also to enrol populations in medical research. The aim of this study was to generate normal ranges of laboratory values for haemoglobin among healthy Ethiopian adults and children and to determine if anaemia is a possible indicator of malaria in women and children in this area of Ethiopia. METHODS: This study was carried out from January 2008 to May 2010. The reference sample population with malaria-negative consisted of 454 individuals, divided women, men and children. The malaria-infected sample population consisted of 117 individuals. The reference ranges were based on the guidelines from the Clinical and Laboratory Standards Institute. Haemoglobin concentration was determined by Hemo-Control EKF Diagnostic Analyser on whole blood. Testing for malaria-positive and negative infection was done by microscopy and by PCR. RESULTS: The lower limits for adult haemoglobin range obtained from this population were slightly higher than those derived from other African populations, but were equal to those established by other studies in Ethiopia and the World Health Organization (WHO). Regarding children, the minimum values were lower than those obtained from different African populations and those established by WHO. The malaria-negative group had anaemia in 35.6% of cases and in the malaria-positive group in 70.9%. There was a stronger, statistically significant association between anaemia and malaria-positive samples than between anaemia and malaria-negative samples in women and both groups of children. CONCLUSIONS: The results from this study are a contribution in the definition of the haemoglobin parameters in African populations, which could be taken as standards for interpretation of laboratory results. The haemoglobin indices in adults from Gambo tended to be higher than other African populations and in children were lower than other studies in Africa. The results also suggest that anaemia is not useful as a supportive diagnostic criterion to monitor and evaluate malaria in women and children from Ethiopia, because a 29.1% of malaria cases will be not detected, because of not having anaemia.


Assuntos
Anemia/parasitologia , Hemoglobinas/análise , Malária/sangue , Adulto , Anemia/epidemiologia , Estudos de Casos e Controles , Criança , Pré-Escolar , Etiópia/epidemiologia , Feminino , Humanos , Malária/epidemiologia , Masculino , Valores de Referência
17.
Malar J ; 11: 199, 2012 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-22694993

RESUMO

BACKGROUND: Malaria is a leading public health problem in Ethiopia. Accurate diagnosis of Plasmodium infections is crucial for the reduction of malaria in tropical areas and for epidemiological studies. The role of light microscopy (LM) as gold standard has been questioned and, therefore, new molecular methods have been developed for the detection of Plasmodium species. The aim of the present work was to compare different malaria diagnostic methods in order to detect the most common species of Plasmodium and to broaden the knowledge of malaria prevalence in a hospital in a rural area in Ethiopia. METHODS: A cross-sectional survey of 471 individuals was carried out in a hospital in the rural area of Gambo (Ethiopia). Blood samples were prepared for microscopic observation and collected in filter paper for Seminested-Multiplex PCR (SnM-PCR) and real time PCR (qPCR) testing. The SnM-PCR was considered as the gold standard technique and compared with the rest. Thus, agreement between SnM-PCR and LM was determined by calculating Kappa Statistics and correlation between LM and qPCR quantification was calculated by pair-wise correlation co-efficient. RESULTS: Samples analysed by LM and SnM-PCR were positive for Plasmodium sp. 5.5% and 10.5%, respectively. Sensitivity was 52.2% by LM and 70% by qPCR. Correlation co-efficient between microscopy counts and qPCR densities for Plasmodium vivax was R2 = 0.586. Prevalence was estimated at 7% (95% CI: 4.7-9.3). Plasmodium vivax was the dominant species detected and the difference was statistically significant (χ2 = 5.121 p < 0.05). The highest prevalence of the parasite (10.9%) was observed in age groups under 15 years old. CONCLUSION: Accurate malaria diagnostic methods have a great effect in the reduction of the number of malaria-infected individuals. SnM-PCR detection of malaria parasites may be a very useful complement to microscopic examination in order to obtain the real prevalence of each Plasmodium species. Although SnM-PCR shows that it is a good tool for the determination of Plasmodium species, today light microscopy remains the only viabletool for malaria diagnosis in developing countries. Therefore, re-inforcement in the training of microscopists is essential for making the correct diagnosis of malaria. Plasmodium vivax was the predominant species in Gambo, a meso-endemic area for this species.


Assuntos
Técnicas de Laboratório Clínico/métodos , Malária/diagnóstico , Malária/epidemiologia , Microscopia/métodos , Biologia Molecular/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Sangue/parasitologia , Criança , Pré-Escolar , Estudos Transversais , Etiópia/epidemiologia , Feminino , Hospitais , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase Multiplex/métodos , Reação em Cadeia da Polimerase/métodos , Reação em Cadeia da Polimerase em Tempo Real/métodos , População Rural , Sensibilidade e Especificidade , Adulto Jovem
18.
Antimicrob Agents Chemother ; 54(12): 5151-5, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20855732

RESUMO

Pathogenic strains of the genus Acanthamoeba are causative agents of severe infections, such as fatal encephalitis and a sight-threatening amoebic keratitis. Antimicrobial therapy for these infections is generally empirical, and patient recovery is often problematic, due to the existence of a highly resistant cyst stage in these amoebae. In previous studies, small interfering RNAs (siRNAs) against the catalytic domains of extracellular serine proteases and glycogen phosphorylase from Acanthamoeba were designed and evaluated for future therapeutic use. The silencing of proteases resulted in Acanthamoeba failing to degrade human corneal cells, and silencing of glycogen phosphorylase caused amoebae to be unable to form mature cysts. After the siRNA design and concentration were optimized in order to avoid toxicity problems, cultures of Acanthamoeba were treated with a combination of both siRNAs, and cells were evaluated under an inverted microscope. This siRNA-based treatment dramatically affected the growth rate and cellular survival of the amoebae. These results were observed less than 48 h after the initiation of the treatment. In order to check possible toxic effects of the siRNA combination, three eukaryotic cell lines (HeLa, murine macrophages, and osteosarcoma cells) were treated with the same molecules, and cytotoxicity was examined by measuring lactate dehydrogenase release. The future use of the combination of these siRNAs is proposed as a potential therapeutic approach against pathogenic strains of Acanthamoeba.


Assuntos
Acanthamoeba/efeitos dos fármacos , Amebíase/parasitologia , Antiprotozoários/farmacologia , RNA Interferente Pequeno/farmacologia , Acanthamoeba/genética , Amebíase/tratamento farmacológico , Animais , Linhagem Celular , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Inativação Gênica/efeitos dos fármacos , Células HeLa , Humanos , Camundongos , RNA Interferente Pequeno/efeitos adversos
19.
Eukaryot Cell ; 7(3): 509-17, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18223117

RESUMO

Acanthamoeba infections are difficult to treat due to often late diagnosis and the lack of effective and specific therapeutic agents. The most important reason for unsuccessful therapy seems to be the existence of a double-wall cyst stage that is highly resistant to the available treatments, causing reinfections. The major components of the Acanthamoeba cyst wall are acid-resistant proteins and cellulose. The latter has been reported to be the major component of the inner cyst wall. It has been demonstrated previously that glycogen is the main source of free glucose for the synthesis of cellulose in Acanthamoeba, partly as glycogen levels fall during the encystment process. In other lower eukaryotes (e.g., Dictyostelium discoideum), glycogen phosphorylase has been reported to be the main tool used for glycogen breakdown in order to maintain the free glucose levels during the encystment process. Therefore, it was hypothesized that the regulation of the key processes involved in the Acanthamoeba encystment may be similar to the previously reported regulation mechanisms in other lower eukaryotes. The catalytic domain of the glycogen phosphorylase was silenced using RNA interference methods, and the effect of this phenomenon was assessed by light and electron microscopy analyses, calcofluor staining, expression zymogram assays, and Northern and Western blot analyses of both small interfering RNA-treated and control cells. The present report establishes the role of glycogen phosphorylase during the encystment process of Acanthamoeba. Moreover, the obtained results demonstrate that the enzyme is required for cyst wall assembly, mainly for the formation of the cell wall inner layer.


Assuntos
Acanthamoeba/citologia , Acanthamoeba/enzimologia , Parede Celular/metabolismo , Glicogênio Fosforilase/fisiologia , Proteínas de Protozoários/fisiologia , Acanthamoeba/fisiologia , Animais , Parede Celular/química , Glicogênio Fosforilase/genética , Dados de Sequência Molecular , Proteínas de Protozoários/genética , Interferência de RNA , RNA Interferente Pequeno/genética
20.
Am J Trop Med Hyg ; 77(4): 753-6, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17978083

RESUMO

We surveyed 236 potentially pathogenic Acanthamoeba strains, isolated from water sources in the Canary Islands, for the presence of human adenoviruses (HAdV) using a polymerase chain reaction (PCR)-based typing assay. A total of 34 of these strains were found to be positive for adenovirus belonging to four different HAdV serotypes (HAdV-1, 2, 8, and 37). We found that HAdV-2 was the most frequently encountered serotype amongst the Acanthamoeba strains, and their identification was confirmed by a nested PCR specific for this serotype. We showed that Acanthamoeba genotype T4 was highly associated with serotype HAdV-2, whereas Acanthamoeba genotype T3 was most often associated with adenovirus serotypes related to ocular diseases. Based on these data, we suggest that Acanthamoeba should be considered as a potential reservoir and perhaps even a transmitter of adenoviruses to human and other secondary hosts.


Assuntos
Acanthamoeba/isolamento & purificação , Acanthamoeba/virologia , Adenoviridae/isolamento & purificação , Microbiologia da Água , Adenoviridae/classificação , Adenoviridae/patogenicidade , Amebíase/genética , Amebíase/imunologia , Animais , Humanos , Reação em Cadeia da Polimerase/métodos , Espanha
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