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1.
Amino Acids ; 56(1): 35, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38698213

RESUMO

Chagas disease, caused by the protozoa Trypanosoma cruzi, continues to be a serious public health problem in Latin America, worsened by the limitations in its detection. Given the importance of developing new diagnostic methods for this disease, the present review aimed to verify the number of publications dedicated to research on peptides that demonstrate their usefulness in serodiagnosis. To this end, a bibliographic survey was conducted on the PubMed platform using the keyword "peptide" or "epitope" combined with "Chagas disease" or "Trypanosoma cruzi"; "diagno*" or "serodiagnosis" or "immunodiagnosis", without period restriction. An increasing number of publications on studies employing peptides in ELISA and rapid tests assays was verified, which confirms the expansion of research in this field. It is possible to observe that many of the peptides tested so far originate from proteins widely used in the diagnosis of Chagas, and many of them are part of commercial tests developed. In this sense, as expected, promising results were obtained for several peptides when tested in ELISA, as many of them exhibited sensitivity and specificity values above 90%. Furthermore, some peptides have been tested in several studies, confirming their diagnostic potential. Despite the promising results observed, it is possible to emphasize the need for extensive testing of peptides, using different serological panels, in order to confirm their potential. The importance of producing an effective assay capable of detecting the clinical stages of the disease, as well as new immunogenic antigens that enable new serological diagnostic tools for Chagas disease, is evident.


Assuntos
Doença de Chagas , Ensaio de Imunoadsorção Enzimática , Peptídeos , Trypanosoma cruzi , Doença de Chagas/diagnóstico , Doença de Chagas/imunologia , Doença de Chagas/sangue , Humanos , Trypanosoma cruzi/imunologia , Peptídeos/imunologia , Peptídeos/química , Ensaio de Imunoadsorção Enzimática/métodos , Testes Imunológicos/métodos , Antígenos de Protozoários/imunologia , Antígenos de Protozoários/sangue , Testes Sorológicos/métodos
2.
Parasite Immunol ; 46(5): e13037, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38720446

RESUMO

The treatment for visceral leishmaniasis (VL) causes toxicity in patients, entails high cost and/or leads to the emergence of resistant strains. No human vaccine exists, and diagnosis presents problems related to the sensitivity or specificity of the tests. Here, we tested two phage clones, B1 and D11, which were shown to be protective against Leishmania infantum infection in a murine model as immunotherapeutics to treat mice infected with this parasite species. The phages were used alone or with amphotericin B (AmpB), while other mice received saline, AmpB, a wild-type phage (WTP) or WTP/AmpB. Results showed that the B1/AmpB and D11/AmpB combinations induced polarised Th1-type cellular and humoral responses, which were primed by high levels of parasite-specific IFN-γ, IL-12, TNF-α, nitrite and IgG2a antibodies, which reflected in significant reductions in the parasite load in distinct organs of the animals when analyses were performed 1 and 30 days after the treatments. Reduced organic toxicity was also found in these animals, as compared with the controls. In conclusion, preliminary data suggest the potential of the B1/AmpB and D11/AmpB combinations as immunotherapeutics against L. infantum infection.


Assuntos
Anfotericina B , Anticorpos Antiprotozoários , Imunoterapia , Leishmania infantum , Leishmaniose Visceral , Camundongos Endogâmicos BALB C , Leishmaniose Visceral/imunologia , Leishmaniose Visceral/tratamento farmacológico , Animais , Anfotericina B/uso terapêutico , Anfotericina B/administração & dosagem , Anticorpos Antiprotozoários/sangue , Leishmania infantum/imunologia , Leishmania infantum/efeitos dos fármacos , Camundongos , Imunoterapia/métodos , Feminino , Antiprotozoários/uso terapêutico , Antiprotozoários/administração & dosagem , Imunoglobulina G/sangue , Carga Parasitária , Modelos Animais de Doenças , Técnicas de Visualização da Superfície Celular , Citocinas/metabolismo , Células Th1/imunologia
3.
Microb Cell Fact ; 23(1): 145, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38778337

RESUMO

Recombinant multiepitope proteins (RMPs) are a promising alternative for application in diagnostic tests and, given their wide application in the most diverse diseases, this review article aims to survey the use of these antigens for diagnosis, as well as discuss the main points surrounding these antigens. RMPs usually consisting of linear, immunodominant, and phylogenetically conserved epitopes, has been applied in the experimental diagnosis of various human and animal diseases, such as leishmaniasis, brucellosis, cysticercosis, Chagas disease, hepatitis, leptospirosis, leprosy, filariasis, schistosomiasis, dengue, and COVID-19. The synthetic genes for these epitopes are joined to code a single RMP, either with spacers or fused, with different biochemical properties. The epitopes' high density within the RMPs contributes to a high degree of sensitivity and specificity. The RMPs can also sidestep the need for multiple peptide synthesis or multiple recombinant proteins, reducing costs and enhancing the standardization conditions for immunoassays. Methods such as bioinformatics and circular dichroism have been widely applied in the development of new RMPs, helping to guide their construction and better understand their structure. Several RMPs have been expressed, mainly using the Escherichia coli expression system, highlighting the importance of these cells in the biotechnological field. In fact, technological advances in this area, offering a wide range of different strains to be used, make these cells the most widely used expression platform. RMPs have been experimentally used to diagnose a broad range of illnesses in the laboratory, suggesting they could also be useful for accurate diagnoses commercially. On this point, the RMP method offers a tempting substitute for the production of promising antigens used to assemble commercial diagnostic kits.


Assuntos
Epitopos , Escherichia coli , Proteínas Recombinantes , Escherichia coli/genética , Escherichia coli/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/imunologia , Humanos , Epitopos/imunologia , Epitopos/genética , Testes Imunológicos/métodos , Animais , COVID-19/diagnóstico
4.
Molecules ; 27(3)2022 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-35164183

RESUMO

BACKGROUND: Despite research on the molecular bases of Alzheimer's disease (AD), effective therapies against its progression are still needed. Recent studies have shown direct links between AD progression and neurovascular dysfunction, highlighting it as a potential target for new therapeutics development. In this work, we screened and evaluated the inhibitory effect of natural compounds from native Peruvian plants against tau protein, amyloid beta, and angiotensin II type 1 receptor (AT1R) pathologic AD markers. METHODS: We applied in silico analysis, such as virtual screening, molecular docking, molecular dynamics simulation (MD), and MM/GBSA estimation, to identify metabolites from Peruvian plants with inhibitory properties, and compared them to nicotinamide, telmisartan, and grapeseed extract drugs in clinical trials. RESULTS: Our results demonstrated the increased bioactivity of three plants' metabolites against tau protein, amyloid beta, and AT1R. The MD simulations indicated the stability of the AT1R:floribundic acid, amyloid beta:rutin, and tau:brassicasterol systems. A polypharmaceutical potential was observed for rutin due to its high affinity to AT1R, amyloid beta, and tau. The metabolite floribundic acid showed bioactivity against the AT1R and tau, and the metabolite brassicasterol showed bioactivity against the amyloid beta and tau. CONCLUSIONS: This study has identified molecules from native Peruvian plants that have the potential to bind three pathologic markers of AD.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Descoberta de Drogas , Compostos Fitoquímicos/farmacologia , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/antagonistas & inibidores , Peptídeos beta-Amiloides/metabolismo , Bloqueadores do Receptor Tipo 1 de Angiotensina II/química , Bloqueadores do Receptor Tipo 1 de Angiotensina II/farmacologia , Humanos , Simulação de Acoplamento Molecular , Peru , Compostos Fitoquímicos/química , Plantas/química , Receptor Tipo 1 de Angiotensina/metabolismo , Proteínas tau/antagonistas & inibidores , Proteínas tau/metabolismo
5.
Molecules ; 26(13)2021 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-34202092

RESUMO

(1) Background: The COVID-19 pandemic lacks treatments; for this reason, the search for potential compounds against therapeutic targets is still necessary. Bioinformatics tools have allowed the rapid in silico screening of possible new metabolite candidates from natural resources or repurposing known ones. Thus, in this work, we aimed to select phytochemical candidates from Peruvian plants with antiviral potential against three therapeutical targets of SARS-CoV-2. (2) Methods: We applied in silico technics, such as virtual screening, molecular docking, molecular dynamics simulation, and MM/GBSA estimation. (3) Results: Rutin, a compound present in Peruvian native plants, showed affinity against three targets of SARS-CoV-2. The molecular dynamics simulation demonstrated the high stability of receptor-ligand systems during the time of the simulation. Our results showed that the Mpro-Rutin system exhibited higher binding free energy than PLpro-Rutin and N-Rutin systems through MM/GBSA analysis. (4) Conclusions: Our study provides insight on natural metabolites from Peruvian plants with therapeutical potential. We found Rutin as a potential candidate with multiple pharmacological properties against SARS-CoV-2.


Assuntos
Antivirais/química , Antivirais/farmacologia , Compostos Fitoquímicos/química , Compostos Fitoquímicos/farmacologia , Plantas/química , Plantas/metabolismo , Asteraceae/química , Asteraceae/metabolismo , Proteases 3C de Coronavírus/antagonistas & inibidores , Proteases 3C de Coronavírus/química , Proteínas do Nucleocapsídeo de Coronavírus/antagonistas & inibidores , Proteínas do Nucleocapsídeo de Coronavírus/química , Proteases Semelhantes à Papaína de Coronavírus/antagonistas & inibidores , Proteases Semelhantes à Papaína de Coronavírus/química , Bases de Dados Factuais , Humanos , Lepidium/química , Lepidium/metabolismo , Ligantes , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Peru , Fosfoproteínas/antagonistas & inibidores , Fosfoproteínas/química , Rutina/química , Rutina/farmacologia , SARS-CoV-2
6.
Parasitol Res ; 117(2): 391-403, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29248978

RESUMO

Leishmaniasis has become a significant public health issue in several countries in the world. New products have been identified to treat against the disease; however, toxicity and/or high cost is a limitation. The present work evaluated the antileishmanial activity of a new naphthoquinone derivate, Flau-A [2-(2,3,4-tri-O-acetyl-6-deoxy-ß-L-galactopyranosyloxy)-1,4-naphthoquinone], against promastigote and amastigote-like stages of Leishmania amazonensis and L. infantum. In addition, the cytotoxicity in murine macrophages and human red cells was also investigated. The mechanism of action of Flau-A was assessed in L. amazonensis as well as its efficacy in treating infected macrophages and inhibiting infection of pretreated parasites. Results showed that Flau-A was effective against promastigotes and amastigote-like forms of both parasite species, as well as showed low toxicity in mammalian cells. Results also highlighted the morphological and biochemical alterations induced by Flau-A in L. amazonensis, including loss of mitochondrial membrane potential, as well as increased reactive oxygen species production, cell shrinkage, and alteration of the plasma membrane integrity. The present study demonstrates for the first time the antileishmanial activity of Flau-A against two Leishmania species and suggests that the mitochondria of the parasites may be the main target organelle. Data shown here encourages the use of this molecule in new studies concerning treatment against Leishmania infection in mammalian hosts.


Assuntos
Antiprotozoários/farmacologia , Leishmania infantum/efeitos dos fármacos , Leishmania mexicana/efeitos dos fármacos , Naftoquinonas/farmacologia , Animais , Eritrócitos/efeitos dos fármacos , Feminino , Humanos , Macrófagos/efeitos dos fármacos , Macrófagos/parasitologia , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos BALB C , Mitocôndrias/efeitos dos fármacos , Naftoquinonas/química
7.
Parasitol Res ; 116(4): 1197-1206, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28150041

RESUMO

The serodiagnosis for tegumentary leishmaniasis (TL) presents problems related to the sensitivity and/or specificity of the tests. In the present study, an enzyme-linked immunosorbent assay (ELISA) technique was used to evaluate the performance from a Leishmania braziliensis hypothetical protein, LbHyM, in an attempt to compare its serological reactivity with a soluble Leishmania antigenic preparation (SLA) for the serodiagnosis of cutaneous (CL) and mucosal (ML) leishmaniasis. LbHyM was predicted to be a kinesin-like protein by bioinformatics tools. Serum samples were collected from both CL and ML patients, as well as from those with Chagas disease and from healthy subjects living in endemic or non-endemic areas of TL. Also, sera were collected from patients before and after the treatments, seeking to evaluate their serological follow-up in relation to the anti-protein and anti-parasite antibody levels. When an ELISA-rLbHyM assay was performed, it proved to be significantly more sensitive than ELISA-L. braziliensis SLA in detecting both CL and ML patients. Also, when using sera from Chagas disease patients, the ELISA-rLbHyM proved to be more specific than ELISA-SLA. The anti-protein and anti-parasite antibody levels were also evaluated 6 months after the treatments, and treated patients showed significantly lower levels of specific-rLbHyM antibodies, when compared to the anti-parasite antibody levels. In conclusion, the ELISA-rLbHyM assay can be considered a confirmatory serological technique for the serodiagnosis of L. braziliensis infection and can also be used in the serological follow-up of treated patients, aiming to correlate the low anti-protein antibody levels with the improvement of the healthy state of the patients.


Assuntos
Anticorpos Antiprotozoários/sangue , Doença de Chagas/diagnóstico , Cinesinas/imunologia , Leishmania braziliensis/imunologia , Leishmaniose Cutânea/diagnóstico , Proteínas de Protozoários/imunologia , Adulto , Animais , Anticorpos Antiprotozoários/imunologia , Doença de Chagas/parasitologia , Ensaio de Imunoadsorção Enzimática/métodos , Feminino , Humanos , Leishmania infantum/imunologia , Leishmaniose Cutânea/parasitologia , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade , Testes Sorológicos/métodos , Adulto Jovem
8.
Parasitology ; 142(10): 1335-47, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26099574

RESUMO

Two mimotopes of Leishmania infantum identified by phage display were evaluated as vaccine candidates in BALB/c mice against Leishmania amazonensis infection. The epitope-based immunogens, namely B10 and C01, presented as phage-fused peptides; were used without association of a Th1 adjuvant, and they were administered isolated or in combination into animals. Both clones showed a specific production of interferon-gamma (IFN-γ), interleukin-12 (IL-12) and granulocyte/macrophage colony-stimulating factor (GM-CSF) after in vitro spleen cells stimulation, and they were able to induce a partial protection against infection. Significant reductions of parasite load in the infected footpads, liver, spleen, bone marrow and paws' draining lymph nodes were observed in the immunized mice, in comparison with the control groups (saline, saponin, wild-type and non-relevant clones). Protection was associated with an IL-12-dependent production of IFN-γ, mediated mainly by CD8(+) T cells, against parasite proteins. Protected mice also presented low levels of IL-4 and IL-10, as well as increased levels of parasite-specific IgG2a antibodies. The association of both clones resulted in an improved protection in relation to their individual use. More importantly, the absence of adjuvant did not diminish the cross-protective efficacy against Leishmania spp. infection. This study describes for the first time two epitope-based immunogens selected by phage display technology against L. infantum infected dogs sera, which induced a partial protection in BALB/c mice infected with L. amazonensis.


Assuntos
Bacteriófagos/imunologia , Epitopos/imunologia , Leishmania infantum/imunologia , Vacinas contra Leishmaniose/imunologia , Leishmaniose/prevenção & controle , Vacinas Protozoárias/imunologia , Animais , Células Cultivadas , Feminino , Camundongos , Camundongos Endogâmicos BALB C
9.
Exp Parasitol ; 153: 180-90, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25845753

RESUMO

The development of effective prophylactic strategies to prevent leishmaniasis has become a high priority. No less important than the choice of an antigen, the association of an appropriate adjuvant is necessary to achieve a successful vaccination, as the majority of the tested antigens contain limited immunogenic properties, and need to be supplemented with immune response adjuvants in order to boost their immunogenicity. However, few effective adjuvants that can be used against leishmaniasis exist on the market today; therefore, it is possible to speculate that the research aiming to identify new adjuvants could be considered relevant. Recently, Agaricus blazei extracts have proved to be useful in enhancing the immune response to DNA vaccines against some diseases. This was based on the Th1 adjuvant activity of the polysaccharide-rich fractions from this mushroom. In this context, the present study evaluated purified fractions derived from Agaricus blazei as Th1 adjuvants through in vitro assays of their immune stimulation of spleen cells derived from naive BALB/c mice. Two of the tested six fractions (namely F2 and F4) were characterized as polysaccharide-rich fractions, and were able to induce high levels of IFN-γ, and low levels of IL-4 and IL-10 in the spleen cells. The efficacy of adjuvant action against L. infantum was evaluated in BALB/c mice, with these fractions being administered together with a recombinant antigen, LiHyp1, which was previously evaluated as a vaccine candidate, associated with saponin, against visceral leishmaniasis (VL). The associations between LiHyp1/F2 and LiHyp1/F4 were able to induce an in vivo Th1 response, which was primed by high levels of IFN-γ, IL-12, and GM-CSF, by low levels of IL-4 and IL-10; as well as by a predominance of IgG2a antibodies in the vaccinated animals. After infection, the immune profile was maintained, and the vaccines proved to be effective against L. infantum. The immune stimulatory effects in the BALB/c mice proved to be similar when comparing the F2 and F4 fractions with a known Th1 adjuvant (saponin), though animals vaccinated with saponin did present a slight to moderate inflammatory edema on their hind footpads. In conclusion, the F2 and F4 fractions appear to induce a Th1-type immune response and, in this context, they could be evaluated in association with other protective antigens against Leishmania, as well as in other disease models.


Assuntos
Adjuvantes Imunológicos/administração & dosagem , Agaricus/química , Antígenos de Protozoários/administração & dosagem , Leishmaniose Visceral/prevenção & controle , Polissacarídeos/administração & dosagem , Animais , Anticorpos Antiprotozoários/imunologia , Antígenos de Protozoários/genética , Antígenos de Protozoários/imunologia , Avaliação Pré-Clínica de Medicamentos , Feminino , Humanos , Interferon gama/imunologia , Interleucina-10/imunologia , Interleucina-4/imunologia , Leishmania infantum/genética , Leishmania infantum/imunologia , Leishmaniose Visceral/imunologia , Leishmaniose Visceral/parasitologia , Camundongos , Camundongos Endogâmicos BALB C , Polissacarídeos/imunologia , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Baço/efeitos dos fármacos , Baço/imunologia , Células Th1/imunologia
10.
Pathogens ; 13(3)2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38535539

RESUMO

Sarcocystis spp. are coccidian protozoans belonging to the Apicomplexa phylum. As with other members of this phylum, they are obligate intracellular parasites with complex cellular machinery for the invasion of host cells. Sarcocystis spp. display dixenous life cycles, involving a predator and a prey as definitive and intermediate hosts, respectively. Specifically, these parasites develop sarcocysts in the tissues of their intermediate hosts, ranging in size from microscopic to visible to the naked eye, depending on the species. When definitive hosts consume sarcocysts, infective forms are produced in the digestive system and discharged into the environment via feces. Consumption of oocyst-contaminated water and pasture by the intermediate host completes the parasitic cycle. More than 200 Sarcocystis spp. have been described to infect wildlife, domestic animals, and humans, some of which are of economic or public health importance. Interestingly, Old World camelids (dromedary, domestic Bactrian camel, and wild Bactrian camel) and New World or South American camelids (llama, alpaca, guanaco, and vicuña) can each be infected by two different Sarcocystis spp: Old World camelids by S. cameli (producing micro- and macroscopic cysts) and S. ippeni (microscopic cysts); and South American camelids by S. aucheniae (macroscopic cysts) and S. masoni (microscopic cysts). Large numbers of Old and New World camelids are bred for meat production, but the finding of macroscopic sarcocysts in carcasses significantly hampers meat commercialization. This review tries to compile the information that is currently accessible regarding the biology, epidemiology, phylogeny, and diagnosis of Sarcocystis spp. that infect Old and New World camelids. In addition, knowledge gaps will be identified to encourage research that will lead to the control of these parasites.

11.
Trop Med Infect Dis ; 9(2)2024 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-38393130

RESUMO

Visceral Leishmaniasis (VL) has a high death rate, with 500,000 new cases and 50,000 deaths occurring annually. Despite the development of novel strategies and technologies, there is no adequate treatment for the disease. Therefore, the purpose of this study is to find structural analogs of natural products as potential novel drugs to treat VL. We selected structural analogs from natural products that have shown antileishmanial activities, and that may impede the purine salvage pathway using computer-aided drug-design (CADD) approaches. For these, we started with the vastly studied target in the pathway, the adenine phosphoribosyl transferase (APRT) protein, which alone is non-essential for the survival of the parasite. Keeping this in mind, we search for a substance that can bind to multiple targets throughout the pathway. Computational techniques were used to study the purine salvage pathway from Leishmania infantum, and molecular dynamic simulations were used to gather information on the interactions between ligands and proteins. Because of its low homology to human proteins and its essential role in the purine salvage pathway proteins network interaction, the findings further highlight the significance of adenylosuccinate lyase protein (ADL) as a therapeutic target. An analog of the alkaloid Skimmianine, N,N-diethyl-4-methoxy-1-benzofuran-6-carboxamide, demonstrated a good binding affinity to APRT and ADL targets, no expected toxicity, and potential for oral route administration. This study indicates that the compound may have antileishmanial activity, which was granted in vitro and in vivo experiments to settle this finding in the future.

12.
Front Pharmacol ; 15: 1403203, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38873424

RESUMO

Visceral Leishmaniasis (VL) is a serious public health issue, documented in more than ninety countries, where an estimated 500,000 new cases emerge each year. Regardless of novel methodologies, advancements, and experimental interventions, therapeutic limitations, and drug resistance are still challenging. For this reason, based on previous research, we screened natural products (NP) from Nuclei of Bioassays, Ecophysiology, and Biosynthesis of Natural Products Database (NuBBEDB), Mexican Compound Database of Natural Products (BIOFACQUIM), and Peruvian Natural Products Database (PeruNPDB) databases, in addition to structural analogs of Miglitol and Acarbose, which have been suggested as treatments for VL and have shown encouraging action against parasite's N-glycan biosynthesis. Using computer-aided drug design (CADD) approaches, the potential inhibitory effect of these NP candidates was evaluated by inhibiting the Mannosyl-oligosaccharide Glucosidase Protein (MOGS) from Leishmania infantum, an enzyme essential for the protein glycosylation process, at various pH to mimic the parasite's changing environment. Also, computational analysis was used to evaluate the Absorption, Distribution, Metabolism, Excretion, and Toxicity (ADMET) profile, while molecular dynamic simulations were used to gather information on the interactions between these ligands and the protein target. Our findings indicated that Ocotillone and Subsessiline have potential antileishmanial effects at pH 5 and 7, respectively, due to their high binding affinity to MOGS and interactions in the active center. Furthermore, these compounds were non-toxic and had the potential to be administered orally. This research indicates the promising anti-leishmanial activity of Ocotillone and Subsessiline, suggesting further validation through in vitro and in vivo experiments.

13.
Pathogens ; 13(6)2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38921753

RESUMO

Visceral leishmaniasis is a disease caused by protozoa of the species Leishmania (Leishmania) infantum (syn = Leishmania chagasi) and Leishmania (Leishmania) donovani, which are transmitted by hematophagous insects of the genera Lutzomyia and Phlebotomus. The domestic dog (Canis familiaris) is considered the main urban reservoir of the parasite due to the high parasite load on its skin, serving as a source of infection for sandfly vectors and, consequently, perpetuating the disease in the urban environment. Some factors are considered important in the perpetuation and spread of canine visceral leishmaniasis (CVL) in urban areas, such as stray dogs, with their errant behavior, and houses that have backyards with trees, shade, and organic materials, creating an attractive environment for sandfly vectors. CVL is found in approximately 50 countries, with the number of infected dogs reaching millions. However, due to the difficulty of controlling and diagnosing the disease, the number of infected animals could be even greater. In the four continents endemic for CVL, there are reports of disease expansion in endemic countries such as Brazil, Italy, Morocco, and Tunisia, as well as in areas where CVL is not endemic, for example, Uruguay. Socio-environmental factors, such as migration, drought, deforestation, and global warming, have been pointed out as reasons for the expansion into areas where it had been absent. Thus, the objective of this review is to address (i) the distribution of CVL in endemic areas, (ii) the role of the dog in the visceral leishmaniasis epidemiology and the factors that influence dog infection and the spread of the disease, and (iii) the challenges faced in the control of CVL.

14.
F1000Res ; 12: 93, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37424744

RESUMO

Introduction: Leishmaniasis is a disease with high mortality rates and approximately 1.5 million new cases each year. Despite the new approaches and advances to fight the disease, there are no effective therapies. Methods: Hence, this study aims to screen for natural products' structural analogs as new drug candidates against leishmaniasis. We applied Computer-aided drug design (CADD) approaches, such as virtual screening, molecular docking, molecular dynamics simulation, molecular mechanics-generalized Born surface area (MM-GBSA) binding free estimation, and free energy perturbation (FEP) aiming to select structural analogs from natural products that have shown anti-leishmanial and anti-arginase activities and that could bind selectively against the Leishmania arginase enzyme. Results: The compounds 2H-1-benzopyran, 3,4-dihydro-2-(2-methylphenyl)-(9CI), echioidinin, and malvidin showed good results against arginase targets from three parasite species and negative results for potential toxicities. The echioidinin and malvidin ligands generated interactions in the active center at pH 2.0 conditions by MM-GBSA and FEP methods. Conclusions: This work suggests the potential anti-leishmanial activity of the compounds and thus can be further in vitro and in vivo experimentally validated.


Assuntos
Produtos Biológicos , Desenho de Fármacos , Leishmania , Leishmaniose , Humanos , Arginase/metabolismo , Arginase/farmacologia , Arginase/uso terapêutico , Produtos Biológicos/farmacologia , Leishmania/metabolismo , Leishmaniose/tratamento farmacológico , Simulação de Acoplamento Molecular
15.
Diagnostics (Basel) ; 13(9)2023 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-37174941

RESUMO

In this paper, we present a systematic review and meta-analysis that aims to evaluate the reliability of coronavirus disease diagnostic tests in 2019 (COVID-19). This article seeks to describe the scientific discoveries made because of diagnostic tests conducted in recent years during the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic. Between 2020 and 2021, searches for published papers on the COVID-19 diagnostic were made in the PubMed database. Ninety-nine scientific articles that satisfied the requirements were analyzed and included in the meta-analysis, and the specificity and sensitivity of the diagnostic accuracy were assessed. When compared to serological tests such as the enzyme-linked immunosorbent assay (ELISA), chemiluminescence immunoassay (CLIA), lateral flow immunoassay (LFIA), and chemiluminescent microparticle immunoassay (CMIA), molecular tests such as reverse transcription polymerase chain reaction (RT-PCR), reverse transcription loop-mediated isothermal amplification (RT-LAMP), and clustered regularly interspaced short palindromic repeats (CRISPR) performed better in terms of sensitivity and specificity. Additionally, the area under the curve restricted to the false-positive rates (AUCFPR) of 0.984 obtained by the antiviral neutralization bioassay (ANB) diagnostic test revealed significant potential for the identification of COVID-19. It has been established that the various diagnostic tests have been effectively adapted for the detection of SARS-CoV-2; nevertheless, their performance still must be enhanced to contain potential COVID-19 outbreaks, which will also help contain potential infectious agent outbreaks in the future.

16.
Sci Rep ; 13(1): 7577, 2023 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-37165197

RESUMO

Since the number of drugs based on natural products (NPs) represents a large source of novel pharmacological entities, NPs have acquired significance in drug discovery. Peru is considered a megadiverse country with many endemic species of plants, terrestrial, and marine animals, and microorganisms. NPs databases have a major impact on drug discovery development. For this reason, several countries such as Mexico, Brazil, India, and China have initiatives to assemble and maintain NPs databases that are representative of their diversity and ethnopharmacological usage. We describe the assembly, curation, and chemoinformatic evaluation of the content and coverage in chemical space, as well as the physicochemical attributes and chemical diversity of the initial version of the Peruvian Natural Products Database (PeruNPDB), which contains 280 natural products. Access to PeruNPDB is available for free ( https://perunpdb.com.pe/ ). The PeruNPDB's collection is intended to be used in a variety of tasks, such as virtual screening campaigns against various disease targets or biological endpoints. This emphasizes the significance of biodiversity protection both directly and indirectly on human health.


Assuntos
Produtos Biológicos , Animais , Humanos , Peru , Avaliação Pré-Clínica de Medicamentos , Produtos Biológicos/farmacologia , Produtos Biológicos/química , Bases de Dados Factuais , Descoberta de Drogas
17.
Pathogens ; 12(2)2023 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-36839519

RESUMO

Malaria is a parasitic infection that is a great public health concern and is responsible for high mortality rates worldwide. Different strategies have been employed to improve disease control, demonstrating the ineffectiveness of controlling vectors, and parasite resistance to antimalarial drugs requires the development of an effective preventive vaccine. There are countless challenges to the development of such a vaccine directly related to the parasite's complex life cycle. After more than four decades of basic research and clinical trials, the World Health Organization (WHO) has recommended the pre-erythrocytic Plasmodium falciparum (RTS, S) malaria vaccine for widespread use among children living in malaria-endemic areas. However, there is a consensus that major improvements are needed to develop a vaccine with a greater epidemiological impact in endemic areas. This review discusses novel strategies for malaria vaccine design taking the target stages within the parasite cycle into account. The design of the multi-component vaccine shows considerable potential, especially as it involves transmission-blocking vaccines (TBVs) that eliminate the parasite's replication towards sporozoite stage parasites during a blood meal of female anopheline mosquitoes. Significant improvements have been made but additional efforts to achieve an efficient vaccine are required to improve control measures. Different strategies have been employed, thus demonstrating the ineffectiveness in controlling vectors, and parasite resistance to antimalarial drugs requires the development of a preventive vaccine. Despite having a vaccine in an advanced stage of development, such as the RTS, S malaria vaccine, the search for an effective vaccine against malaria is far from over. This review discusses novel strategies for malaria vaccine design taking into account the target stages within the parasite's life cycle.

18.
Front Mol Neurosci ; 16: 1104585, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36873109

RESUMO

Evidence suggests that there may be racial differences in risk factors associated with the development of Alzheimer's disease and related dementia (ADRD). We used whole-genome sequencing analysis and identified a novel combination of three pathogenic variants in the heterozygous state (UNC93A: rs7739897 and WDR27: rs61740334; rs3800544) in a Peruvian family with a strong clinical history of ADRD. Notably, the combination of these variants was present in two generations of affected individuals but absent in healthy members of the family. In silico and in vitro studies have provided insights into the pathogenicity of these variants. These studies predict that the loss of function of the mutant UNC93A and WDR27 proteins induced dramatic changes in the global transcriptomic signature of brain cells, including neurons, astrocytes, and especially pericytes and vascular smooth muscle cells, indicating that the combination of these three variants may affect the neurovascular unit. In addition, known key molecular pathways associated with dementia spectrum disorders were enriched in brain cells with low levels of UNC93A and WDR27. Our findings have thus identified a genetic risk factor for familial dementia in a Peruvian family with an Amerindian ancestral background.

19.
Vet Sci ; 10(10)2023 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-37888541

RESUMO

The blood-sucking mites Dermanyssus gallinae ("red mite"), Ornithonyssus sylviarum ("northern fowl mite"), and Ornithonyssus bursa ("tropical fowl mite") stand out for causing infestations in commercial poultry farms worldwide, resulting in significant economic damage for producers. In addition to changes in production systems that include new concerns for animal welfare, global climate change in recent years has become a major challenge in the spread of ectoparasites around the world. This review includes information regarding the main form of controlling poultry mites through the use of commercially available chemicals. In addition, non-chemical measures against blood-sucking mites were discussed such as extracts and oils from plants and seeds, entomopathogenic fungi, semiochemicals, powder such as diatomaceous earth and silica-based products, and vaccine candidates. The control of poultry mites using chemical methods that are currently used to control or eliminate them are proving to be less effective as mites develop resistance. In contrast, the products based on plant oils and extracts, powders of plant origin, fungi, and new antigens aimed at developing transmission-blocking vaccines against poultry mites provide some encouraging options for the rational control of these ectoparasites.

20.
Curr Mol Med ; 2023 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-37461338

RESUMO

BACKGROUND: Monkeypox is a global public health issue caused by the monkeypox virus (MPXV). As of October 28, 2022, a total of 77,115 laboratory-confirmed cases and 3,610 probable cases, including 36 deaths, were reported, with 9,070 cases reported in Brazil, the second most affected country. The need to develop national technologies for the rapid diagnosis of emerging diseases for mass testing of the population is evident, as observed in the SARS-CoV-2 pandemic. OBJECTIVE: With that in mind, this article provides an overview of current methods, techniques, and their applications in the molecular detection of monkeypox, focusing the search on real-time polymerase chain reaction (qPCR), polymerase chain reaction (PCR), and polymerase chain reaction-enzyme linked immunosorbent assay (PCR-ELISA). METHODS: The relevant documents or papers covered in this study were selected by a search in international bibliographic databases. The search terms used in the databases were aimed at summarizing existing knowledge on molecular diagnostic methods, such as monkeypox; MPX, MPXV, qPCR, PCR, PCR-ELISA, diagnosis and detection searched separately or together using the Boolean operator "AND" either in the title or abstract. The searches took place in September 2022, and the corresponding articles were selected between 2012 and 2022. RESULTS: We found 256 documents in total and twelve studies addressing the molecular diagnosis of monkeypox were classified as possible sources for this review. CONCLUSION: It is evident there is a pressing need to develop national technologies for rapid diagnosis of emerging diseases for mass testing of the population. It is also extremely important to have national detection kits with greater diagnostic capacity to assist in developing effective public policies in countries affected by this disease.

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