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1.
Trop Anim Health Prod ; 53(3): 392, 2021 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-34231076

RESUMO

Blood and faecal samples from 2086 Sahelian and Djallonke sheep have been collected to assess the epidemiology and spatio-temporal distribution of gastrointestinal parasites. A survey with a questionnaire allowed collecting data on individual animal and farms. Faecal samples were analysed using the McMaster technique, while anaemia was assessed using FAMACHA score test and packed cell volume. The overall prevalence of gastrointestinal parasites was 91%, and strongyles (70.7%), Eimeria sp. (60.4%), Moniezia sp. (5.7%), Stronyloides sp. (0.9%) were identified. There was no significant association between the region and strongyles infection (P ˃ 0.05). Animals sampled during the rainy season (n = 565; P = 82.2%, mean EPG = 154.8 ± 12.02) were mostly and heavily infected than those from the hot dry (n = 518; P = 74.2%; mean EPG = 97.7 ± 17.4) and the cold dry season (n = 392; P = 55.5%; mean EPG = 24.5 ± 19.5) (P ˂ 0.05). Females (n = 1027; P = 72.1%; mean EPG = 77.6 ± 17) were most infected than males (n = 448; P = 67.7%; mean EPG = 61.6 ± 19.5) (P ˂ 0.05). Animals that were treated, at most 3 months before sampling (n = 166; P = 61.5%; mean EPG = 41.7 ± 21.4), were less infected than those, which received this treatment after three months before sampling (n = 199; P = 74.8%; mean EPG = 89.1 ± 15.8) (P ˂ 0.05). Data from blood samples indicate that 6.5% of sheep was anaemic (PCV ≤ 19%), while 59.7% was noted anaemic regarding FAMACHA scores. PCV values varied significantly for FAMACHA scores, and the highest mean value was noted for score 1 (27.6) (P ˂ 0.05). The Cohen's kappa score between FAMACHA and PCV was 0.02. These findings suggest that strongyles infections are significantly associated with season, and heavier infections were noted during rainy season.


Assuntos
Hemoncose , Haemonchus , Parasitos , Doenças dos Ovinos , Agricultura , Animais , Burkina Faso/epidemiologia , Fazendas , Fezes , Feminino , Hemoncose/diagnóstico , Hemoncose/epidemiologia , Hemoncose/veterinária , Masculino , Contagem de Ovos de Parasitas/veterinária , Ovinos , Doenças dos Ovinos/diagnóstico , Doenças dos Ovinos/epidemiologia
2.
Int J Mol Sci ; 22(13)2021 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-34209520

RESUMO

The worldwide development of antimicrobial resistance forces scientists to search for new compounds to which microbes would be sensitive. Many new structures contain the 1,3,4-oxadiazole ring, which have shown various antimicrobial activity, e.g., antibacterial, antitubercular, antifungal, antiprotozoal and antiviral. In many publications, the activity of new compounds exceeds the activity of already known antibiotics and other antimicrobial agents, so their potential as new drugs is very promising. The review of active antimicrobial 1,3,4-oxadiazole derivatives is based on the literature from 2015 to 2021.


Assuntos
Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Oxidiazóis/química , Oxidiazóis/farmacologia , Animais , Bactérias/efeitos dos fármacos , Fungos/efeitos dos fármacos , Humanos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Parasitos/efeitos dos fármacos , Relação Estrutura-Atividade , Vírus/efeitos dos fármacos
3.
Front Cell Infect Microbiol ; 11: 672691, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34222045

RESUMO

Elucidation of the mechanisms of drug resistance in malaria parasites is crucial for combatting the emergence and spread of resistant parasites, which can be achieved by tracing resistance-associated mutations and providing useful information for drug development. Previously, we produced a novel genetic tool, a Plasmodium berghei mutator (PbMut), whose base substitution rate is 36.5 times higher than that of wild-type parasites. Here, we report the isolation of a mutant with reduced susceptibility to piperaquine (PPQ) from PbMut under PPQ pressure by sequential nine-cycle screening and named it PbMut-PPQ-R-P9. The ED50 of PbMut-PPQ-R-P9 was 1.79 times higher than that of wild-type parasites, suggesting that its PPQ resistance is weak. In the 1st screen, recrudescence occurred in the mice infected with PbMut but not in those infected with wild-type parasites, suggesting earlier emergence of PPQ-resistant parasites from PbMut. Whole-genome sequence analysis of PbMut-PPQ-R-P9 clones revealed that eight nonsynonymous mutations were conserved in all clones, including N331I in PbCRT, the gene encoding chloroquine resistance transporter (CRT). The PbCRT(N331I) mutation already existed in the parasite population after the 2nd screen and was predominant in the population after the 8th screen. An artificially inserted PbCRT(N331I) mutation gave rise to reduced PPQ susceptibility in genome-edited parasites (PbCRT-N331I). The PPQ susceptibility and growth rates of PbCRT-N331I parasites were significantly lower than those of PbMut-PPQ-R-P9, implying that additional mutations in the PbMut-PPQ-R9 parasites could compensate for the fitness cost of the PbCRT(N331I) mutation and contribute to reduced PPQ susceptibility. In summary, PbMut could serve as a novel genetic tool for predicting gene mutations responsible for drug resistance. Further study on PbMut-PPQ-R-P9 could identify genetic changes that compensate for fitness costs owing to drug resistance acquisition.


Assuntos
Antimaláricos , Malária Falciparum , Malária , Parasitos , Animais , Antimaláricos/farmacologia , Malária/tratamento farmacológico , Camundongos , Plasmodium berghei/genética , Plasmodium falciparum , Proteínas de Protozoários/genética , Quinolinas , Roedores
4.
Front Cell Infect Microbiol ; 11: 708952, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34249784

RESUMO

As an adaption to their complex lifecycles, helminth parasites garner a unique repertoire of genes at different developmental stages with subtle regulatory mechanisms. These parasitic worms release differential components such as microRNAs (miRNAs) and extracellular vesicles (EVs) as mediators which participate in the host-parasite interaction, immune regulation/evasion, and in governing processes associated with host infection. MiRNAs are small (~ 22-nucleotides) non-coding RNAs that regulate gene expression at the post-transcriptional level, and can exist in stable form in bodily fluids such as serum/plasma, urine, saliva and bile. In addition to reports focusing on the identification of miRNAs or in the probing of differentially expressed miRNA profiles in different development stages/sexes or in specific tissues, a number of studies have focused on the detection of helminth-derived miRNAs in the mammalian host circulatory system as diagnostic biomarkers. Extracellular vesicles (EVs), small membrane-surrounded structures secreted by a wide variety of cell types, contain rich cargos that are important in cell-cell communication. EVs have attracted wide attention due to their unique functional relevance in host-parasite interactions and for their potential value in translational applications such as biomarker discovery. In the current review, we discuss the status and potential of helminth parasite-derived circulating miRNAs and EV cargos as novel diagnostic tools.


Assuntos
Vesículas Extracelulares , Helmintos , MicroRNAs , Parasitos , Animais , Biomarcadores , Helmintos/genética , MicroRNAs/genética
5.
Rev Bras Parasitol Vet ; 30(3): e006021, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34259740

RESUMO

The present study investigated the metazoan parasite community in Pimelodus ornatus from the Amazon River, in the state of Amapá (Brazil). Of 71 fish examined, 70.4% were parasitized by Demidospermus sp. (Monogenea), Cucullanus pinnai, Procamallanus (Spirocamallanus) inopinatus and Contracaecum sp. (Nematoda) and plerocercoids from Proteocephalidae gen. sp. (Cestoda). The dominance was of nematode species such as Procamallanus (S.) inopinatus and Contracaecum sp. The parasites showed a highly aggregated dispersion and a predominance of hosts infected by one species of parasite. The parasite community was characterized by a low Shannon diversity index, low evenness and low species richness. The richness of parasite species, Shannon's diversity index, abundance of P. (S.) inopinatus and Proteocephalidae gen. sp. showed a positive correlation with the length of the hosts. Therefore, the size of the hosts had an influence on the parasite community and infracommunities, as well as their intermediate position in the food web. This is the first record of P. (S.) inopinatus and Contracaecum sp. for P. ornatus.


Assuntos
Peixes-Gato , Cestoides , Parasitos , Animais , Brasil , Rios
6.
Braz J Biol ; 83: e248032, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34259782

RESUMO

A new species of nematode parasite of the subfamily Pudicinae (Heligmosomoidea: Heligmonellidae) is described from the small intestine of Proechimys simonsi (Rodentia: Echimyidae) from the locality of Nova Cintra in the municpality of Rodrigues Alves, Acre state, Brazil. The genus Pudica includes 15 species parasites of Neotropical rodents of the families Caviidae, Ctenomyidae, Dasyproctidae, Echimyidae, Erethizontidae, and Myocastoridae. Four species of this nematode were found parasitizing three different species rodents of the genus Proechimys in the Amazon biome. Pudica wandiquei n. sp. can be differentiated from all other Pudica species by the distance between the ends of rays 6 and 8 and the 1-3-1 pattern of the caudal bursa in both lobes.


Assuntos
Nematoides , Parasitos , Trichostrongyloidea , Animais , Brasil , Roedores
7.
Front Cell Infect Microbiol ; 11: 654216, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34262880

RESUMO

Malaria transmission relies on parasite-mosquito midgut interaction. The interactive proteins are hypothesized to be ideal targets to block malaria transmission to mosquitoes. We chose 76 genes that contain signal peptide-coding regions and are upregulated and highly abundant at sexual stages. Forty-six of these candidate genes (60%) were cloned and expressed using the baculovirus expression system in insect cells. Six of them, e.g., PF3D7_0303900, PF3D7_0406200 (Pfs16), PF3D7_1204400 (Pfs37), PF3D7_1214800, PF3D7_1239400, and PF3D7_1472800 were discovered to interact with blood-fed mosquito midgut lysate. Previous works showed that among these interactive proteins, knockout the orthologs of Pfs37 or Pfs16 in P. berghei reduced oocysts in mosquitoes. Here we further found that anti-Pfs16 polyclonal antibody significantly inhibited P. falciparum transmission to Anopheles gambiae. Investigating these candidate proteins will improve our understanding of malaria transmission and discover new targets to break malaria transmission.


Assuntos
Malária , Parasitos , Plasmodium , Animais , Mosquitos Vetores , Plasmodium falciparum/genética
9.
BMJ Case Rep ; 14(7)2021 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-34285020

RESUMO

We report a case of human fascioliasis in the USA that encountered many diagnostic uncertainties. Numerous tests available for detection of fascioliasis were utilised but the diagnosis remained elusive. Confounders included three negative stool ova and parasite examinations, positive hepatitis A virus IgM antibody, cross-reactive false-positive Echinococcus IgG antibody, absence of characteristic image findings and unrevealing liver biopsy. Praziquantel was started as empiric treatment for helminth infections, but was ineffective. Due to the rarity of the disease in the USA, serologic testing and triclabendazole were only available from the Centers for Disease Control and Prevention, which led to a delay in diagnosis and treatment.


Assuntos
Anti-Helmínticos , Fasciolíase , Parasitos , Animais , Anti-Helmínticos/uso terapêutico , Benzimidazóis/uso terapêutico , Fasciolíase/diagnóstico , Fasciolíase/tratamento farmacológico , Humanos , Triclabendazol/uso terapêutico , Estados Unidos
10.
Biomed Pharmacother ; 139: 111611, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34243597

RESUMO

Trichomonas vaginalis is an amitochondriate protozoan and the agent of human trichomoniasis, the most prevalent non-viral sexually transmitted infection (STI) in the world. In this study we showed that 2,4-diamine-quinazoline derivative compound (PH100) kills T. vaginalis. PH100 showed activity against fresh clinical and American Type Culture Collection (ATCC) T. vaginalis isolates with no cytotoxicity against cells (HMVI, 3T3-C1 and VERO) and erythrocytes. In addition, PH100 showed synergistic action with metronidazole, indicating that these compounds act by different mechanisms. When investigating the mechanism of action of PH100 to ATCC 30236, apoptosis-like characteristics were observed, such as phosphatidylserine exposure, membrane alterations, and modulation of gene expression and activity of peptidases related to apoptosis. The apoptosis-like cell death features were not observed for the fresh clinical isolate treated with PH100 revealing distinct profiles. Our data revealed the heterogeneity among T. vaginalis isolates and contribute with the understanding of mechanisms of cell death in pathogenic eukaryotic organisms without mitochondria.


Assuntos
Diaminas/farmacologia , Parasitos/efeitos dos fármacos , Peptídeo Hidrolases/metabolismo , Quinazolinas/farmacologia , Vaginite por Trichomonas/tratamento farmacológico , Trichomonas vaginalis/efeitos dos fármacos , Células 3T3 , Animais , Apoptose/efeitos dos fármacos , Morte Celular/efeitos dos fármacos , Linhagem Celular , Chlorocebus aethiops , Feminino , Humanos , Metronidazol/farmacologia , Camundongos , Vaginite por Trichomonas/parasitologia , Células Vero
11.
An Acad Bras Cienc ; 93(3): e20190988, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34161511

RESUMO

This study evaluated the presence of metazoan parasites in Leporinus macrocephalus from four fish farms from the western Amazon (Brazil). In 160 fish examined, prevalence was 61.9%, and parasites found were: Urocleidoides paradoxus, Urocleidoides eremitus, Tereancistrum parvus, Jainus leporini, Procamallanus (Spirocamallanus) inopinatus, Rhabdochona (Rhabdochona) acuminata, Dolops discoidalis and Ergasilus sp., but U. paradoxus was the dominant parasite. Jainus leporini and Ergasilus sp. occurred only in L. macrocephalus from one fish farm, while U. paradoxus, U. eremitus and T. parvus were found in fish from three fish farms. Dolops discoidalis, P. (S.) inopinatus and R. (R.) acuminata occurred only in L. macrocephalus from two fish farms. Higher infection levels were caused by U. paradoxus, U. eremitus and P. (S.) inopinatus, which had an aggregated dispersion. There was positive correlation between abundance of parasites and the length of hosts. No difference in the condition factor of parasitized and non-parasitized fish were found. Such differences between fish farms were attributed to differences in management and quality of cultivation environments, and data indicate the need to adopt prophylactic measures in the fish farms to prevent diseases in the future. This was the first report of D. discoidalis and Ergasilus sp. for L. macrocephalus.


Assuntos
Caraciformes , Doenças dos Peixes , Parasitos , Animais , Brasil/epidemiologia , Pesqueiros
12.
Rev Bras Parasitol Vet ; 30(3): e004621, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34190777

RESUMO

The present study describes a new species of the genus Sphaerospora found in the urinary bladder of the flag cichlid, Mesonauta festivus collected in Corre Água district of the municipality of Macapá, Amapá State (Brazil). The study includes morphological and phylogenetic analyses of the new parasite, to determine the relationship of the new species with related myxosporean species. The new species has polysporous plasmodia, which vary in size and shape. The mature myxospores are subspherical shape in valvar view. In the sutural view, the myxospores are 5.3±0.2 (5.2-5.6) µm in length and 7.0±0.7 (6.3-7.7) µm in width, with two piriform polar capsules equal size, 2.5±0.2 (2.3-2.8) µm in length and 1.8±0.2 (1.6-2.0) µm in width. The phylogenetic analyses of a partial sequence of the 18S rRNA gene confirmed the status of the new species and determined the relationship of the new species and related myxosporean species.The sum of the evidence indicates that, Sphaerospora festivus n. sp. belongs to the family Sphaerosporidae, and is the first record of the genus Sphaerospora from Brazil.


Assuntos
Ciclídeos , Doenças dos Peixes , Myxozoa , Parasitos , Doenças Parasitárias em Animais , Animais , Brasil , DNA Ribossômico , Myxozoa/genética , Filogenia
13.
Nat Commun ; 12(1): 3620, 2021 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-34131147

RESUMO

Host membrane remodeling is indispensable for viruses, bacteria, and parasites, to subvert the membrane barrier and obtain entry into cells. The malaria parasite Plasmodium spp. induces biophysical and molecular changes to the erythrocyte membrane through the ordered secretion of its apical organelles. To understand this process and address the debate regarding how the parasitophorous vacuole membrane (PVM) is formed, we developed an approach using lattice light-sheet microscopy, which enables the parasite interaction with the host cell membrane to be tracked and characterized during invasion. Our results show that the PVM is predominantly formed from the erythrocyte membrane, which undergoes biophysical changes as it is remodeled across all stages of invasion, from pre-invasion through to PVM sealing. This approach enables a functional interrogation of parasite-derived lipids and proteins in PVM biogenesis and echinocytosis during Plasmodium falciparum invasion and promises to yield mechanistic insights regarding how this is more generally orchestrated by other intracellular pathogens.


Assuntos
Membrana Eritrocítica/parasitologia , Eritrócitos/parasitologia , Tomografia Computadorizada Quadridimensional/métodos , Interações Hospedeiro-Parasita/fisiologia , Malária/parasitologia , Vacúolos/metabolismo , Animais , Membrana Eritrocítica/metabolismo , Humanos , Merozoítos , Parasitos , Plasmodium/metabolismo , Plasmodium falciparum/metabolismo , Proteínas de Protozoários/metabolismo
14.
Behav Processes ; 189: 104438, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34087347

RESUMO

Females of brood parasitic shiny cowbirds, Molothrus bonariensis, search and prospect host nests, synchronizing parasitism with host laying. This behavior is sex-specific, as females perform this task without male's assistance. Host nests must be removed from the female's memory "library" after being parasitized, to avoid repeated parasitism, or when they become unavailable because of predation. Thus, females must adjust their stored information about host nest status more dynamically than males, possibly leading to differences in learning flexibility. We tested for sex differences in a visual (local cues) and a spatial discrimination reversal learning task, expecting females to outperform males as an expression of greater behavioral flexibility. Both sexes learned faster the spatial than the visual task during both acquisition and reversal. In the visual task there were no sex differences in acquisition, but females reversed faster than males. In the spatial task there were no sex differences during either acquisition or reversal, possibly because of a ceiling effect: both sexes learned too fast for differences in performance to be detectable. Faster female reversal in a visual but not spatial task indicates that the greater behavioral flexibility in females may only be detectable above some level of task difficulty.


Assuntos
Parasitos , Passeriformes , Animais , Feminino , Masculino , Comportamento de Nidação , Comportamento Predatório , Caracteres Sexuais
15.
BMC Infect Dis ; 21(1): 576, 2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-34130649

RESUMO

BACKGROUND: Both capillary and venous blood samples have been interchangeably used for the diagnosis of malaria in Ethiopia. However, Plasmodium parasites are thought to be more concentrated in capillary than in venous blood. Hence, selecting a sample source where parasites are more concentrated is indispensable approach in order to maximize the accuracy of blood film microscopy. Therefore, the present study aimed to compare the detection rate and the parasitemia level of Plasmodium species from conventional capillary and venous blood films, and buffy coat preparations. METHODS: A facility based cross-sectional study was conducted from Feburary to March 2020 among 210 febrile patients attending Hamusite health center, northwest Ethiopia. Capillary and venous blood samples were collected and buffy coat was prepared from each sample. Thin and thick blood films were prepared, stained, and examined microscopically following standard protocol. Data were analysed using Statistical Package for Social Sciences Software version 20 and Med-Calc software version 19.3. RESULTS: Capillary blood buffy coat (61/210, 29.0%) had significantly higher detection rate as compared to capillary (48/210, 22.9%) and venous (42/210, 20.0%) blood films (p < 0.001). However, no significant difference was observed between capillary and venous blood films (p = 0.070) in detecting Plasmodium species. The highest and the lowest mean asexual stage parasite counts were found in capillary blood buffy coat (4692.88) and venous blood (631.43) films, respectively showing significant variations (p < 0.001). Mean gametocyte count was also highest in capillary blood buffy coat (3958.44). As compared to capillary blood buffy coat, the sensitivity of venous blood buffy coat, capillary blood film and venous blood film were 73.8, 78.7, 68.9%, respectively. CONCLUSION: Capillary blood buffy coat samples showed the highest sensitivity in detecting and quantitating malaria parasites that its use should be promoted in clinical settings. However, conventional capillary and venous blood films could be used interchangeably.


Assuntos
Testes Hematológicos/métodos , Malária/diagnóstico , Plasmodium/isolamento & purificação , Adolescente , Adulto , Animais , Buffy Coat/parasitologia , Coleta de Amostras Sanguíneas/métodos , Capilares/parasitologia , Criança , Estudos Transversais , Etiópia , Feminino , Humanos , Malária/sangue , Masculino , Microscopia/métodos , Parasitemia/parasitologia , Parasitos , Veias/parasitologia , Adulto Jovem
16.
BMJ Case Rep ; 14(6)2021 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-34183311

RESUMO

A 31-year-old woman, presenting with right upper quadrant pain, was suspected to have malignant gall bladder polyp based on MRI and CT scan findings. She underwent radical cholecystectomy with excision of bile duct and hepaticojejunostomy. Surprisingly, histology revealed parasitic remnants within the bile duct wall with no evidence of malignancy. A year later, this young woman suffers significant impairment of quality of life, perhaps an aftermath to the radicality of the surgery. Our case demonstrates a masquerade of 'malignant biliary polyp' by a parasite. This raises the need for extensive investigations such as endoscopic ultrasound guided biopsies, parasitic serology and positron emission tomography (PET) scans when patients present with probable malignant biliary lesions, even in difficult-to-access areas. A preoperative diagnosis might have averted an unnecessary major surgery in this young woman.


Assuntos
Doenças da Vesícula Biliar , Parasitos , Adulto , Animais , Colecistectomia , Feminino , Doenças da Vesícula Biliar/diagnóstico por imagem , Doenças da Vesícula Biliar/cirurgia , Humanos , Qualidade de Vida
17.
Front Cell Infect Microbiol ; 11: 687647, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34178725

RESUMO

American Tegumentary Leishmaniasis (ATL) is an endemic disease in Latin America, mainly caused in Brazil by Leishmania (Viannia) braziliensis. Clinical manifestations vary from mild, localized cutaneous leishmaniasis (CL) to aggressive mucosal disease. The host immune response strongly determines the outcome of infection and pattern of disease. However, the pathogenesis of ATL is not well understood, and host microRNAs (miRNAs) may have a role in this context. In the present study, miRNAs were quantified using qPCR arrays in human monocytic THP-1 cells infected in vitro with L. (V.) braziliensis promastigotes and in plasma from patients with ATL, focusing on inflammatory response-specific miRNAs. Patients with active or self-healed cutaneous leishmaniasis patients, with confirmed parasitological or immunological diagnosis, were compared with healthy controls. Computational target prediction of significantly-altered miRNAs from in vitro L. (V.) braziliensis-infected THP-1 cells revealed predicted targets involved in diverse pathways, including chemokine signaling, inflammatory, cellular proliferation, and tissue repair processes. In plasma, we observed distinct miRNA expression in patients with self-healed and active lesions compared with healthy controls. Some miRNAs dysregulated during THP-1 in vitro infection were also found in plasma from self-healed patients, including miR-548d-3p, which was upregulated in infected THP-1 cells and in plasma from self-healed patients. As miR-548d-3p was predicted to target the chemokine pathway and inflammation is a central to the pathogenesis of ATL, we evaluated the effect of transient transfection of a miR-548d-3p inhibitor on L. (V.) braziliensis infected-THP-1 cells. Inhibition of miR-548d-3p reduced parasite growth early after infection and increased production of MCP1/CCL2, RANTES/CCL5, and IP10/CXCL10. In plasma of self-healed patients, MCP1/CCL2, RANTES/CCL5, and IL-8/CXCL8 concentrations were significantly decreased and MIG/CXCL9 and IP-10/CXCL10 increased compared to patients with active disease. These data suggest that by modulating miRNAs, L. (V.) braziliensis may interfere with chemokine production and hence the inflammatory processes underpinning lesion resolution. Our data suggest miR-548d-3p could be further evaluated as a prognostic marker for ATL and/or as a host-directed therapeutic target.


Assuntos
Leishmania braziliensis , MicroRNAs , Parasitos , Animais , Brasil , Humanos , Inflamação , MicroRNAs/genética
18.
Front Cell Infect Microbiol ; 11: 691121, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34178727

RESUMO

Parasites of the phylum Apicomplexa impact humans in nearly all parts of the world, causing diseases including to toxoplasmosis, cryptosporidiosis, babesiosis, and malaria. Apicomplexan parasites have complex life cycles comprised of one or more stages characterized by rapid replication and biomass amplification, which enables accelerated evolutionary adaptation to environmental changes, including to drug pressure. The emergence of drug resistant pathogens is a major looming and/or active threat for current frontline chemotherapies, especially for widely used antimalarial drugs. In fact, resistant parasites have been reported against all modern antimalarial drugs within 15 years of clinical introduction, including the current frontline artemisinin-based combination therapies. Chemotherapeutics are a major tool in the public health arsenal for combatting the onset and spread of apicomplexan diseases. All currently approved antimalarial drugs have been discovered either through chemical modification of natural products or through large-scale screening of chemical libraries for parasite death phenotypes, and so far, none have been developed through a gene-to-drug pipeline. However, the limited duration of efficacy of these drugs in the field underscores the need for new and innovative approaches to discover drugs that can counter rapid resistance evolution. This review details both historical and current antimalarial drug discovery approaches. We also highlight new strategies that may be employed to discover resistance-resistant drug targets and chemotherapies in order to circumvent the rapid evolution of resistance in apicomplexan parasites.


Assuntos
Antimaláricos , Malária , Parasitos , Animais , Antimaláricos/farmacologia , Descoberta de Drogas , Resistência a Medicamentos , Humanos , Malária/tratamento farmacológico , Plasmodium falciparum
19.
Artigo em Inglês | MEDLINE | ID: mdl-34073025

RESUMO

Rodents are one of the most diversified terrestrial mammals, and they perform several beneficial activities in nature. These animals are also important as carriers of many pathogens with public health importance. The current systematic review was conducted to formulate a true depiction of rodent-related zoonoses in Qatar. Following systematic searches on PubMed, Scopus, Science Direct, and Web of Science and a screening process, a total of 94 published articles were selected and studied. The studied articles reported 23 rodent-related zoonotic pathogens that include nine bacterial, eleven parasitic, and three viral pathogens, from which the frequently reported pathogens were Mycobacterium tuberculosis (32 reports), Escherichia coli (23), and Salmonella spp. (16). The possible pathway of entry of the rodent-borne pathogens can be the land port, seaports, and airport of Qatar through carrier humans and animals, contaminated food, and agricultural products. The pathogens can be conserved internally by rodents, pets, and livestock; by agricultural production systems; and by food marketing chains. The overall estimated pooled prevalence of the pathogens among the human population was 4.27% (95%CI: 4.03-4.51%; p < 0.001) with significant heterogeneity (I2 = 99.50%). The top three highest prevalent pathogens were M. tuberculosis (30.90%; 22.75-39.04%; p < 0.001; I2 = 99.70%) followed by Toxoplasma gondii (21.93%; 6.23-37.61%; p < 0.001; I2 = 99.30%) and hepatitis E virus (18.29%; 11.72-24.86%; p < 0.001; I2 = 96.70%). However, there is a knowledge gap about the listed pathogens regarding the occurrence, transmission pathways, and rodent role in transmission dynamics at the human-animal-environment interface in Qatar. Further studies are required to explore the role of rodents in spreading zoonotic pathogens through the One Health framework, consisting of zoologists, ecologists, microbiologists, entomologists, veterinarians, and public health experts in this country.


Assuntos
Parasitos , Roedores , Animais , Humanos , Gado , Catar/epidemiologia , Zoonoses
20.
BMC Ecol Evol ; 21(1): 108, 2021 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-34078265

RESUMO

BACKGROUND: Feather feeding lice are abundant and diverse ectoparasites that complete their entire life cycle on an avian host. The principal or sole source of nutrition for these lice is feathers. Feathers appear to lack four amino acids that the lice would require to complete development and reproduce. Several insect groups have acquired heritable and intracellular bacteria that can synthesize metabolites absent in an insect's diet, allowing insects to feed exclusively on nutrient-poor resources. Multiple species of feather feeding lice have been shown to harbor heritable and intracellular bacteria. We expected that these bacteria augment the louse's diet with amino acids and facilitated the evolution of these diverse and specialized parasites. Heritable symbionts of insects often have small genomes that contain a minimal set of genes needed to maintain essential cell functions and synthesize metabolites absent in the host insect's diet. Therefore, we expected the genome of a bacterial endosymbiont in feather lice would be small, but encode pathways for biosynthesis of amino acids. RESULTS: We sequenced the genome of a bacterial symbiont from a feather feeding louse (Columbicola wolffhuegeli) that parasitizes the Pied Imperial Pigeon (Ducula bicolor) and used its genome to predict metabolism of amino acids based on the presence or absence of genes. We found that this bacterial symbiont has a small genome, similar to the genomes of heritable symbionts described in other insect groups. However, we failed to identify many of the genes that we expected would support metabolism of amino acids in the symbiont genome. We also evaluated other gene pathways and features of the highly reduced genome of this symbiotic bacterium. CONCLUSIONS: Based on the data collected in this study, it does not appear that this bacterial symbiont can synthesize amino acids needed to complement the diet of a feather feeding louse. Our results raise additional questions about the biology of feather chewing lice and the roles of symbiotic bacteria in evolution of diverse avian parasites.


Assuntos
Iscnóceros , Parasitos , Animais , Bactérias/genética , Genoma Bacteriano/genética , Simbiose
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