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1.
Tropical Biomedicine ; : 392-399, 2023.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-1011282

RESUMO

@#Blastocystis is a prevalent infectious agent found in the gastrointestinal tract of humans and animals. While the morphology of Blastocystis has been extensively studied, there is still a lack of comprehensive research on its ultrastructure, especially regarding surface characteristics and their correlation with pathogenic potential. Additionally, the subtyping of Blastocystis does not provide information on the isolate’s pathogenicity. This study aimed to examine the morphology and the cell surface of Blastocystis in avian and non-human primates, including peafowl, pheasant, and lion-headed tamarin. By employing light microscopy and scanning electron microscopy (SEM), this study provides the first evidence of the cellular and surface features of Blastocystis in these animal species. Our findings revealed distinct variations in cell size, shape, and surface morphology among the different host species. Notably, the isolates from peafowl exhibited larger cell sizes compared to the isolates from the pheasant. However, interestingly, both animal species were found to exhibit the same Blastocystis ST6. It was also observed that the surface structure of Blastocystis from different hosts displayed a diverse range of patterns, including mesh-like appearances, deep indentations, and attachments to bacteria. Additionally, findings also revealed the presence of a rough surface structure in peafowl, a characteristic that has been previously linked to pathogenicity and symptomatic infection in animals, as indicated by earlier studies. The findings contribute to our understanding of the morphological features and the surface characteristic of Blastocystis in different host species, shedding light on the parasite’s adaptations and potential implications for host health.

2.
Trop Biomed ; 40(4): 392-399, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38308825

RESUMO

Blastocystis is a prevalent infectious agent found in the gastrointestinal tract of humans and animals. While the morphology of Blastocystis has been extensively studied, there is still a lack of comprehensive research on its ultrastructure, especially regarding surface characteristics and their correlation with pathogenic potential. Additionally, the subtyping of Blastocystis does not provide information on the isolate's pathogenicity. This study aimed to examine the morphology and the cell surface of Blastocystis in avian and non-human primates, including peafowl, pheasant, and lion-headed tamarin. By employing light microscopy and scanning electron microscopy (SEM), this study provides the first evidence of the cellular and surface features of Blastocystis in these animal species. Our findings revealed distinct variations in cell size, shape, and surface morphology among the different host species. Notably, the isolates from peafowl exhibited larger cell sizes compared to the isolates from the pheasant. However, interestingly, both animal species were found to exhibit the same Blastocystis ST6. It was also observed that the surface structure of Blastocystis from different hosts displayed a diverse range of patterns, including mesh-like appearances, deep indentations, and attachments to bacteria. Additionally, findings also revealed the presence of a rough surface structure in peafowl, a characteristic that has been previously linked to pathogenicity and symptomatic infection in animals, as indicated by earlier studies. The findings contribute to our understanding of the morphological features and the surface characteristic of Blastocystis in different host species, shedding light on the parasite's adaptations and potential implications for host health.


Assuntos
Infecções por Blastocystis , Blastocystis , Animais , Humanos , Infecções por Blastocystis/veterinária , Primatas , Microscopia Eletrônica de Varredura , Fezes
3.
Trop Biomed ; 39(1): 144-149, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-35507937

RESUMO

Accurate diagnosis and prompt treatment are highly essential in the management of malaria, which is one of the deadliest infectious diseases worldwide, particularly in tropical and sub-tropical regions including Nigeria. This study was designed to evaluate the efficacy of malaria histidine-rich protein 2-based rapid diagnostic test (RDT) and microscopy in the diagnosis of falciparum malaria in Nigeria. This was a cross-sectional and hospital-based study. The standard method of microscopy was used as the gold standard. Giemsa stained thick and thin smears were prepared to count and detect malaria parasite species. Also, a malaria histidine-rich protein 2-based RDT was used to detect malaria parasites and diagnostic efficacy were determined through the measure of sensitivity, specificity, Positive Predictive Value (PPV), Negative Predictive Value (NPV), diagnostic accuracy and Youden Index (J). The result showed that out of the total 303 individuals examined, a total malaria prevalence of 67.0% and 68.0% were recorded for micr oscopy and RDT, respectively. Additionally, the sensitivity (95% C.I), specificity (95% C.I), PPV (95% C.I), and NPV (95% C.I) of RDT compared to microscopy were 97.54 (94.36-98.94), 92.00 (85.00-95.89), 96.12 (92.53-98.02), and 94.85 (88.50- 97.78), respectively. The diagnostic accuracy (95% C.I) and Youden Index (J) were 95.71 (92.77- 97.70) and 0.89, respectively. Conclusively, our study revealed that RDT continues to remain efficacious. Thus, while malaria diagnosis by microscopy which is the gold standard remains the major method of malaria detection, it should be complemented by rapid diagnostic test (RDT), particularly in high malaria endemic regions where mean parasite density of patients are usually high.


Assuntos
Malária Falciparum , Malária , Antígenos de Protozoários , Estudos Transversais , Testes Diagnósticos de Rotina/métodos , Histidina , Humanos , Malária Falciparum/epidemiologia , Microscopia/métodos , Nigéria , Plasmodium falciparum , Proteínas de Protozoários , Sensibilidade e Especificidade
4.
Tropical Biomedicine ; : 144-149, 2022.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-936421

RESUMO

@#Accurate diagnosis and prompt treatment are highly essential in the management of malaria, which is one of the deadliest infectious diseases worldwide, particularly in tropical and sub-tropical regions including Nigeria. This study was designed to evaluate the efficacy of malaria histidine-rich protein 2-based rapid diagnostic test (RDT) and microscopy in the diagnosis of falciparum malaria in Nigeria. This was a cross-sectional and hospital-based study. The standard method of microscopy was used as the gold standard. Giemsa stained thick and thin smears were prepared to count and detect malaria parasite species. Also, a malaria histidine-rich protein 2-based RDT was used to detect malaria parasites and diagnostic efficacy were determined through the measure of sensitivity, specificity, Positive Predictive Value (PPV), Negative Predictive Value (NPV), diagnostic accuracy and Youden Index (J). The result showed that out of the total 303 individuals examined, a total malaria prevalence of 67.0% and 68.0% were recorded for microscopy and RDT, respectively. Additionally, the sensitivity (95% C.I), specificity (95% C.I), PPV (95% C.I), and NPV (95% C.I) of RDT compared to microscopy were 97.54 (94.36-98.94), 92.00 (85.00-95.89), 96.12 (92.53-98.02), and 94.85 (88.50- 97.78), respectively. The diagnostic accuracy (95% C.I) and Youden Index (J) were 95.71 (92.77- 97.70) and 0.89, respectively. Conclusively, our study revealed that RDT continues to remain efficacious. Thus, while malaria diagnosis by microscopy which is the gold standard remains the major method of malaria detection, it should be complemented by rapid diagnostic test (RDT), particularly in high malaria endemic regions where mean parasite density of patients are usually high.

5.
Trop Biomed ; 38(1): 14-21, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33797518

RESUMO

Malaria which is caused by parasites of the genus Plasmodium is a devastating parasitic disease of major public health challenge worldwide, particularly Nigeria. This study was carried out to investigate the epidemiology of falciparum malaria among residents of rural and peri-urban communities in Ekiti State, Southwestern Nigeria. Standard parasitological technique of microscopy was employed to determine and identify parasite prevalence and species. A questionnaire was used to collect subject's information such as age, sex, location, occupation and education. Out of the 300 individuals examined, a total of 283 (93.4%) individuals were infected with malaria parasite. Sex pattern of infection indicated that male had higher malaria prevalence of 95.0% compared to female with the prevalence of 93.3% (P>0.05). The age group 51 to 60 years had the highest malaria parasite prevalence of 100% while age group <10 years has the least malaria parasite prevalence of 86.0% (P>0.05). Similarly, a total mean malaria parasite density of 1455.90 parasite/µL of blood was recorded. The mean malaria parasite density does not significantly vary (P>0.05) among age and sex group. The age group >60 years recorded the highest mean parasite density of 2092.50 parasite/µL of blood while age group <10 has the least mean malaria parasite density of 1044. 42 parasite/µL of blood. In relation to sex, the highest mean malaria parasite density was found among the female (1461.80 parasite/µL of blood) compared to male (1450 parasite/ µL of blood). In the same vein, occupation as a socioeconomic risk factor play a major role with respect to malaria infection. The highest malaria prevalence of 113 (98.26%) was recorded among farmers while the least 34 (85%) was recorded among Civil servants (P<0.05). Thus, it is apparent that falciparum malaria is heavily prevalent in this study area and as such urgent management control measures and interventions should be made available and fully utilized.


Assuntos
Malária Falciparum/epidemiologia , Adolescente , Adulto , Criança , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Nigéria/epidemiologia , Ocupações , Prevalência , População Rural , Adulto Jovem
6.
Tropical Biomedicine ; : 14-21, 2021.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-882181

RESUMO

@#Malaria which is caused by parasites of the genus Plasmodium is a devastating parasitic disease of major public health challenge worldwide, particularly Nigeria. This study was carried out to investigate the epidemiology of falciparum malaria among residents of rural and peri-urban communities in Ekiti State, Southwestern Nigeria. Standard parasitological technique of microscopy was employed to determine and identify parasite prevalence and species. A questionnaire was used to collect subject’s information such as age, sex, location, occupation and education. Out of the 300 individuals examined, a total of 283 (93.4%) individuals were infected with malaria parasite. Sex pattern of infection indicated that male had higher malaria prevalence of 95.0% compared to female with the prevalence of 93.3% (P>0.05). The age group 51 to 60 years had the highest malaria parasite prevalence of 100% while age group <10 years has the least malaria parasite prevalence of 86.0% (P>0.05). Similarly, a total mean malaria parasite density of 1455.90 parasite/μL of blood was recorded. The mean malaria parasite density does not significantly vary (P>0.05) among age and sex group. The age group >60 years recorded the highest mean parasite density of 2092.50 parasite/μL of blood while age group <10 has the least mean malaria parasite density of 1044. 42 parasite/μL of blood. In relation to sex, the highest mean malaria parasite density was found among the female (1461.80 parasite/μL of blood) compared to male (1450 parasite/ μL of blood). In the same vein, occupation as a socioeconomic risk factor play a major role with respect to malaria infection. The highest malaria prevalence of 113 (98.26%) was recorded among farmers while the least 34 (85%) was recorded among Civil servants (P<0.05). Thus, it is apparent that falciparum malaria is heavily prevalent in this study area and as such urgent management control measures and interventions should be made available and fully utilized.

7.
Trop Biomed ; 34(4): 1000-1013, 2017 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-33592971

RESUMO

Cathepsin L (CPL) cysteine protease is a proteolytic enzyme that involves in many biological processes in a wide range of organisms. In free-living nematode Caenorhabditis elegans, CPL plays important roles in embryogenesis and development processes. The CPL protein is also believed to have a role in degradation of blood meal in the gut of parasitic nematodes. Considering this enzyme might play the same functions in parasitic nematodes, CPL became a potential candidate for vaccination against Haemonchus contortus, a gastrointestinal nematode of small ruminants. H. contortus has been shown to have variations in term of morphology and genetic materials that correlated with different hosts and geographical areas. These variations could hinder the development of effective vaccines. Thus, the present study was conducted to clone and characterize recombinant Hc-CPL-1 from H. contortus isolated from a goat population in Penang, Malaysia. Reverse transcription polymerase chain reaction (RT-PCR) was used to amplify target complimentary DNA (cDNA) from total RNA and protein expression using Escherichia coli expression system was performed from constructed cDNA clone library. The identity of each protein band was confirmed by liquid chromatography-mass spectrometry (LC-MS) analysis followed by De novo sequencing and database matching. The protein structure and its evolutionary relationship were also studied using several bioinformatics approaches. Basic local alignment search tool (BLAST) analysis of the strain retrieved from clone library showed 99% sequence similarity to the Haemonchus cathepsin L cysteine protease and a 47 kDA protein was successfully expressed. Bioinformatic analysis indicated that this protease has a close relationship with Dv-CPL-1, Sv-CPL-1 and Ce-CPL-1. These data might provide an insight on manipulating this enzyme for future novel vaccine development.

8.
Vet Parasitol ; 190(1-2): 127-35, 2012 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-22749290

RESUMO

This study aimed to represent the first report of the ovicidal and larvicidal activity of the methanolic leaf extract of Manihot esculenta (cassava) against eggs and larvae of susceptible and resistant strains of Trichostrongylus colubriformis. As well as, to determine the total tannin compounds, antioxidant activity and toxicity of the extract. The egg hatch test was used to evaluate ovicidal activity against unembryonated eggs, whereas larval feeding inhibition assay and MTT-formazan assay were used to evaluate larvicidal activity against first (L(1)) and infective (L(3)) larvae, respectively. The results showed no significant differences were detected between the sensitivities of susceptible and resistant strains of T. colubriformis to the extract. Eggs, L(1) and L(3) were significantly affected (P<0.001) compared with negative control, and L(1) were more sensitive than the eggs and L(3). The total tannin compounds were investigated using tannin quantification assay and determined by 254.44 TAE/mg. The antioxidant activity was evaluated using the DPPH radical scavenging assay and the median inhibition concentration (IC(50)) was determined by 2.638 mg/ml. Acute oral toxicity at dose of 5,000 mg/kg, and sub-chronic oral toxicity at 500 and 1,000 mg/kg of the extract were observed in male and female Sprague-Dawley (SD) rats. The acute oral toxicity revealed that the median lethal dose (LD(50)) of methanolic extract of cassava leaves on SD rats was greater than 5,000 mg/kg, whereas the sub-chronic oral toxicity did not show observed adverse effects at 500 and 1,000 mg/kg per day for 28 days. In conclusion, the methanolic extract of cassava leaves has direct ovicidal and larvicidal activity against T. colubriformis strains with a safety margin for animals, and it may be potentially utilized as a source of natural antioxidants.


Assuntos
Anti-Helmínticos/farmacologia , Manihot/química , Extratos Vegetais/farmacologia , Tricostrongilose/parasitologia , Trichostrongylus/efeitos dos fármacos , Animais , Anti-Helmínticos/toxicidade , Antioxidantes/metabolismo , Resistência a Medicamentos , Feminino , Concentração Inibidora 50 , Larva/efeitos dos fármacos , Dose Letal Mediana , Masculino , Extratos Vegetais/química , Extratos Vegetais/toxicidade , Folhas de Planta/química , Ratos , Ratos Sprague-Dawley , Taninos/análise , Tricostrongilose/tratamento farmacológico
9.
Vet Parasitol ; 188(1-2): 85-92, 2012 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-22455724

RESUMO

Anthelmintic resistance of gastrointestinal nematodes is considered as one of the main limiting factors causing significant economic losses to the small ruminant industry. The anthelmintic properties of some plants are among the suggested alternative solutions to control these parasitic worms. The present study investigated the anthelmintic activity of neem (Azadirachta indica) and cassava (Manihot esculenta) leaf extracts against the susceptible and resistant strains of one of the most important nematodes in small ruminants, Teladorsagia (Ostertagia) circumcincta. Three different in vitro tests: egg hatch test, larval development assay, and larval paralysis assay were used to determine the efficiency of neem and cassava extracts on three pre-parasitic stages of T. circumcincta. The LC(50) was determined for the most potent extract in each plant as well as the phytochemical tests, total tannin quantification and cytotoxicity on peripheral blood mononuclear cells of goats. The results revealed a high anthelmintic activity of neem methanol extract (NME) and cassava methanol extract (CME) on both strains of T. circumcincta without significant differences between the strains. The first stage larvae were more sensitive with the lowest LC(50) at 7.15 mg/ml and 10.72 mg/ml for NME and CME, respectively, compared with 44.20mg/ml and 56.68 mg/ml on eggs and 24.91 mg/ml and 71.96 mg/ml on infective stage larvae.


Assuntos
Anti-Helmínticos/farmacologia , Azadirachta/química , Manihot/química , Ostertagia/efeitos dos fármacos , Extratos Vegetais/farmacologia , Albendazol/farmacologia , Animais , Resistência a Medicamentos , Larva/efeitos dos fármacos , Ostertagia/genética , Extratos Vegetais/química
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