RESUMO
Dengue is a significant disease transmitted by Aedes mosquitoes in the tropics and subtropics worldwide. The disease is caused by four virus (DENV) serotypes and is transmitted to humans by female Aedes aegypti mosquito bites infected with the virus and vertically to their progeny. Current strategies to control dengue transmission focus on the vector. In this study, we describe an indirect Enzyme-Linked Immunosorbent Assay (ELISA), using a monoclonal antibody against the non-structural dengue virus protein 1 (NS1), to detect DENV2 in Ae. aegypti eggs. The assay detects NS1 in eggs homogenates with 87.5% sensitivity and 75.0% specificity and it is proposed as a tool for the routine entomovirological surveillance of DENV 2 in field mosquito populations.
RESUMO
The MutS homolog 6 (MSH6) is a nuclear DNA mismatch repair (MMR) gene that encodes the MSH6 protein. MSH6 interacts with MSH2 to form the MutSα heterodimer. MutSα corrects DNA mismatches and unpaired nucleotides arising during DNA replication, deamination of 5-methylcytosine, and recombination between non-identical DNA sequences. In addition to correcting DNA biosynthetic errors, MutSα also recognizes chemically damaged DNA bases. Here, we show that inactivation of MSH6 affects the basal susceptibility of Arabidopsis thaliana to Pseudomonas syringae pv tomato DC3000. The msh6 T-DNA insertional mutant exhibited a reduced susceptibility to the bacterial invasion. This heightened basal resistance of msh6 mutants appears to be dependent on an increased stomatal closure, an accumulation of H2O2 and double-strand breaks (DSBs) and a constitutive expression of pathogenesis-related (NPR1 and PR1) and DNA damage response (RAD51D and SOG1) genes. Complementation of this mutant with the MSH6 wild type allele under the control of its own promoter resulted in reversal of the basal bacterial resistance phenotype and the stomatal closure back to wild type levels. Taken together, these results demonstrate that inactivation of MSH6 increases Arabidopsis basal susceptibility to the bacterial pathogen and suggests a link between DNA repair and stress signaling in plants.
Assuntos
Proteínas de Arabidopsis , Arabidopsis , Proteínas de Ligação a DNA , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , DNA , Reparo de Erro de Pareamento de DNA , Proteínas de Ligação a DNA/genética , Peróxido de Hidrogênio , Proteína 2 Homóloga a MutS/genética , Proteína 2 Homóloga a MutS/metabolismo , Pseudomonas syringae/fisiologia , Proteínas Repressoras/metabolismo , Fatores de Transcrição/genéticaRESUMO
Cancer patients experience several symptoms throughout their illness and the treatments they receive. While this pathology represents a worldwide health problem, knowing the symptom prevalence in oncology patients remains a challenge; validated tools to obtain this information are essential. Furthermore, this prevalence information would help health professionals to establish appropriate treatments. The objective of this study was to ascertain the symptom prevalence in cancer patients from Spain and Colombia to improve future approaches. The frequency, severity, and distress of 32 symptoms from a validated scale experienced by cancer patients from Spain and Colombia were measured. Two hundred and forty-six patients (49.7%) who attended the Day University Hospital of Salamanca (Spain) and two hundred and forty-nine outpatients (50.3%) of the San Diego Cancer Center (Colombia) between 2016 and 2019 participated in the study. All patients filled in the Assessment Scale only once. Four hundred and ninety-five patients (333 women (67.3%) and 162 men (32.7%)) completed the Memorial Symptom Assessment Scale (Spanish version). The most frequent symptom for both samples (Spanish and Colombian) was "lack of energy" (38.4% and 13.7%, respectively). The most severe symptoms for the Spanish and Colombian samples were "problems with sexual interest or activity" (38.4%) and "dry mouth" (13.7%), respectively, and both samples agreed on the most distressing symptom: "hair loss" (Spanish, 38%; Colombian, 10.1%). The Spanish version of the MSAS has proven to be a valid and reliable tool in Spanish-speaking countries to obtain the most prevalent, severe, and distressing symptoms in Spanish and Colombian oncology patients. The prevalence of symptoms was demonstrated to be similar across both countries, and the results will help to design and adapt treatments for cancer patients, targeting these symptoms to reduce or avoid them and thus improving their quality of life.
RESUMO
BACKGROUND: ROR2 is a tyrosine-kinase receptor whose expression is dysregulated in many human diseases. In cancer, ROR2 stimulates proliferation, survival, migration, and metastasis, and is associated with more aggressive tumor stages. The purpose of this work is to study the role of ROR2 in the chemoresistance of melanoma. METHODS: Gain- and loss-of-function experiments were used to study the biological function of ROR2 in melanoma. Cell death induced by chemotherapeutic drugs and BH-3 mimetics was evaluated using crystal violet cytotoxicity assays and annexin V/propidium iodide staining. Western blots were used to evaluate the expression of proteins implicated in cell death. The differences observed between cells with manipulation of ROR2 levels and control cells were evaluated using both Student's t-test and ANOVA. RESULTS: We describe that ROR2 contributes to tumor progression by enhancing the resistance of melanoma cells to both chemotherapeutic drugs and BH-3 mimetics. We demonstrate that ROR2 reduced cell death upon treatment with cisplatin, dacarbazine, lomustine, camptothecin, paclitaxel, ABT-737, TW-37, and venetoclax. This effect was mediated by the inhibition of apoptosis. In addition, we investigated the molecular mechanisms implicated in this role of ROR2. We identified the MDM2/p53 pathway as a novel target of ROR2 since ROR2 positively regulates MDM2 levels, thus leading to p53 downregulation. We also showed that ROR2 also upregulates Mcl-1 and Bcl2-xL while it negatively regulates Bax and Bid expression. The effect of ROR2 on the expression of these proteins is mediated by the hyperactivation of ERK. CONCLUSIONS: These results demonstrate that ROR2 contributes to melanoma progression by inhibiting apoptosis and increasing chemoresistance. These results not only position ROR2 as a marker of chemoresistance but also support its use as a novel therapeutic target in cancer.
Assuntos
MAP Quinases Reguladas por Sinal Extracelular , Melanoma , Proteínas Proto-Oncogênicas c-bcl-2 , Receptores Órfãos Semelhantes a Receptor Tirosina Quinase , Proteína Supressora de Tumor p53 , Apoptose , Linhagem Celular Tumoral , Cisplatino/farmacologia , Resistencia a Medicamentos Antineoplásicos , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Humanos , Melanoma/tratamento farmacológico , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Receptores Órfãos Semelhantes a Receptor Tirosina Quinase/genética , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismoRESUMO
Dengue fever is one of the most devastating infectious diseases worldwide. Development of methods for dengue virus (DENV) detection in mosquitoes to assess prevalence as a preliminary screen for entomological surveillance in endemic regions of DENV will certainly contribute to the control of the disease. A monoclonal antibody against the NS1 (nonstructural protein 1) viral protein was generated using recombinant NS1 protein and used to detect and analyze DENV in both excreta and total homogenates from Aedes aegypti mosquitoes. Results demonstrated expression of NS1 in excreta of DENV laboratory-infected mosquitoes and homogenates from field mosquitoes infected with DENV. The immunodetection method reported here represents a first-line strategy for assessing the prevalence of DENV in mosquitoes, for entomological surveillance in endemic regions of dengue. Detection of DENV prevalence in field mosquitoes could have an impact on vector surveillance measures to interrupt dengue transmission.
Assuntos
Aedes , Vírus da Dengue , Animais , Anticorpos Monoclonais , Mosquitos VetoresRESUMO
In invertebrates, "immunological priming" is considered as the ability to acquire a protective (adaptive) immune response against a pathogen due to previous exposure to the same organism. To date, the mechanism by which this type of adaptive immune response originates in insects is not well understood. In the Anopheles albimanus - Plasmodium berghei model, a DNA synthesis that probably indicates an endoreplication process during priming induction has been evidenced. This work aimed to know the transcriptomic profile in the midguts of An. albimanus after priming induction. Our analysis indicates the participation of regulatory elements of the cell cycle in the immunological priming and points out the importance of the cell cycle regulation in the mosquito midgut.
Assuntos
Imunidade Adaptativa , Anopheles/imunologia , Interações Hospedeiro-Parasita/imunologia , Plasmodium berghei/imunologia , Animais , Anopheles/parasitologia , Ciclo Celular/imunologia , Epigênese Genética/imunologia , Perfilação da Expressão Gênica , Interações Hospedeiro-Parasita/genética , Masculino , CamundongosRESUMO
Chikungunya virus (CHIKV) is an alphavirus transmitted by Aedes mosquitoes, which causes Chikungunya fever. Three CHIKV genotypes have been identified: West African, East-Central-South African and Asian. In 2014, CHIKV was detected for the first time in Mexico, accumulating 13,569 confirmed cases in the following three years. Studies on the molecular diversification of CHIKV in Mexico focused on limited geographic regions or investigated only one structural gene of the virus. To describe the dynamics of this outbreak, we analyzed 309 serum samples from CHIKV acute clinical cases from 15 Mexican states. Partial NSP3, E1, and E2 genes were sequenced, mutations were identified, and their genetic variability was estimated. The evolutionary relationship with CHIKV sequences sampled globally were analyzed. Our sequences grouped with the Asian genotype within the Caribbean lineage, suggesting that the Asian was the only circulating genotype during the outbreak. Three non-synonymous mutations (E2 S248F and NSP3 A437T and L451F) were present in our sequences, which were also identified in sequences of the Caribbean lineage and in one Philippine sequence. Based on the phylogeographic analysis, the viral spread was reconstructed, suggesting that after the introduction through the Mexican southern border (Chiapas), CHIKV dispersed to neighboring states before reaching the center and north of the country through the Pacific Ocean states and Quintana Roo. This is the first viral phylogeographic reconstruction in Mexico characterizing the CHIKV outbreak across the country.
Assuntos
Febre de Chikungunya/virologia , Vírus Chikungunya/classificação , Vírus Chikungunya/genética , Variação Genética , Epidemiologia Molecular , Aedes/virologia , Animais , Região do Caribe , Febre de Chikungunya/epidemiologia , Surtos de Doenças , Genótipo , México/epidemiologia , Mutação , Oceano Pacífico , Filogenia , FilogeografiaRESUMO
The heat shock protein family 70 (Hsp70) comprises chaperone proteins that play major multiple roles in Plasmodium asexual and sexual development. In this study, we analyzed the expression of Hsp70-1 in gametocytes, gametes, zygotes, and its participation in ookinete formation and their transition into oocysts. A monoclonal antibody against recombinant Hsp70-1 revealed its presence in zygotes and micronemes of ookinetes. Compared to wild type parasites, Hsp70-1 knockout ookinetes produced fewer oocysts in Plasmodium-susceptible Anopheles albimanus mosquitoes. This may indicate a defective transformation of ookinetes into oocysts in the absence of Hsp70-1. The presence of this protein in micronemes suggests its participation in mosquito infection, probably aiding to the adequate structural conformation of proteins in charge of motility, recognition and invasion of the insect midgut epithelium.
Assuntos
Anopheles/parasitologia , Expressão Gênica , Proteínas de Choque Térmico HSP70/genética , Plasmodium berghei/genética , Proteínas de Protozoários/genética , Animais , Trato Gastrointestinal/parasitologia , Vetores Genéticos/genética , Estágios do Ciclo de Vida , Masculino , Fenótipo , Plasmodium berghei/crescimento & desenvolvimento , Ratos , Zigoto/metabolismoRESUMO
Plant ribosomal proteins play universal roles in translation, although they are also involved in developmental processes and hormone signaling pathways. Among Arabidopsis RPL10 family members, RPL10A exhibits the highest expression during germination and early development, suggesting that RPL10A is the main contributor to these processes. In this work, we first analyzed RPL10A expression pattern in Arabidopsis thaliana using transgenic RPL10Apro:GUS plants. The gene exhibits a ubiquitous expression pattern throughout the plant, but it is most strongly expressed in undifferentiated tissues. Interestingly, gene expression was also detected in stomatal cells. We then examined protein function during seedling establishment and abscisic acid (ABA) response. Heterozygous rpl10A mutant plants show decreased ABA-sensitivity during seed germination, are impaired in early seedling and root development, and exhibit reduced ABA-inhibition of stomatal aperture under light conditions. Overexpression of RPL10A does not affect the germination and seedling growth, but RPL10A-overexpressing lines are more sensitive to ABA during early plant development and exhibit higher stomatal closure under light condition both with and without ABA treatment than wild type plants. Interestingly, RPL10A expression is induced by ABA. Together, we conclude that RPL10A could act as a positive regulator for ABA-dependent responses in Arabidopsis plants.
RESUMO
Several natural and synthetic polypeptides possess important antimalarial activity. Shorter peptides with potent antimalarial activity have also been described, among them linear di-, tri-, tetra- and pentapeptides and their cyclic analogs. In an attempt to find dipeptides with antimalarial activities we show that linear and cyclic dipeptides, the latter known as diketopiperazines, still retain the fundamental core to preserve antimalarial activity. Thirteen linear dipeptides and ten diketopiperazines were investigated. Eight linear dipeptides showed IC(50) values between 2.78 and 7.07 µM, while eight diketopiperazines were also active with IC(50) values between 2.26 and 4.26 µM on Plasmodium berghei schizont cultures.
Assuntos
Antimaláricos/química , Dipeptídeos/química , Antimaláricos/síntese química , Antimaláricos/farmacologia , Cristalografia por Raios X , Dipeptídeos/síntese química , Dipeptídeos/farmacologia , Conformação Molecular , Peptídeos Cíclicos/síntese química , Peptídeos Cíclicos/química , Peptídeos Cíclicos/farmacologia , Plasmodium berghei/efeitos dos fármacosRESUMO
We have synthesized two new benzologues of Nitazoxanide (NIT) and Tizoxanide (TIZ), using a short synthetic route. Both compounds were tested in vitro against six protozoa (Giardia intestinalis, Trichomonas vaginalis, Entamoeba histolytica, Plasmodium berghei, Leishmania mexicana and Trypanosoma cruzi). Compound 1 (benzologue of NIT) showed broad antiprotozoal effect against all parasites tested, showing IC(50)'s<5 µM. This compound was five-times more active than NIT, and 18-times more potent than metronidazole against G. intestinalis. It was 10-times more active than pentamidine against L. mexicana, and it was sevenfold more potent than benznidazole versus T. cruzi. This compound could be considered as a new broad spectrum antiprotozoal agent.
Assuntos
Antiprotozoários/síntese química , Antiprotozoários/farmacologia , Tiazóis , Giardia/efeitos dos fármacos , Estrutura Molecular , Nitrocompostos , Plasmodium/efeitos dos fármacos , Tiazóis/síntese química , Tiazóis/farmacologia , Trichomonas vaginalis/efeitos dos fármacosRESUMO
A series of ten novel hybrids from benzimidazole and pentamidine were prepared using a short synthetic route. Each compound was tested in vitro against the protozoa Trichomonas vaginalis, Giardia lamblia, Entamoeba histolytica, Leishmania mexicana, and Plasmodium berghei, in comparison with pentamidine and metronidazole. Some analogues showed high bioactivity in the low micromolar range (IC(50)<1 microM) against the first four protozoa, which make them significantly more potent than either standard. 1,5-bis[4-(5-methoxy-1H-benzimidazole-2-yl)phenoxy]pentane (2) was 3- and 9-fold more potent againstG. lamblia than metronidazole and pentamidine, respectively. This compound was 23-, 108-, and 13-fold more active than pentamidine against T. vaginalis, E. histolytica and L. mexicana, respectively. Studying further structure-activity relationships through the use of bioisosteric substitution in these hybrids should provide new leads against protozoal diseases.
Assuntos
Antiprotozoários/síntese química , Antiprotozoários/farmacologia , Benzimidazóis/síntese química , Benzimidazóis/farmacologia , Desenho de Fármacos , Pentamidina/síntese química , Pentamidina/farmacologia , Animais , Antiprotozoários/química , Benzimidazóis/química , Entamoeba histolytica/efeitos dos fármacos , Giardia lamblia/efeitos dos fármacos , Concentração Inibidora 50 , Leishmania mexicana/efeitos dos fármacos , Metronidazol/farmacologia , Estrutura Molecular , Testes de Sensibilidade Parasitária , Pentamidina/química , Plasmodium berghei/efeitos dos fármacos , Relação Estrutura-Atividade , Trichomonas vaginalis/efeitos dos fármacosRESUMO
Malaria parasite transmission-blocking control strategies within the mosquito vector require an adequate understanding of the parasite mosquito interaction at the molecular level. The ookinete P25-P28 surface proteins are required for the transition from ookinete to oocyst in the mosquito midgut; however, their respective molecular interactions in the mosquito are largely unknown. We used recombinant Pvs25 and Pvs28 as probes for identification of potential Anopheles albimanus midgut ligands. A 50 kDa protein interacted with Pvs25 but not with Pvs28 in blot overlay assays. This protein was identified as calreticulin by LS MS and was detected in membrane, but not in soluble midgut protein extracts. Calreticulin was detected in An. albimanus midgut microvilli by immunofluorescence analysis. The An. albimanus calreticulin cDNA was cloned and recombinant calreticulin was shown to interact with recombinant Pvs25 in overlay and co-immunoprecipitation assays, confirming the interaction of the two proteins. The Pvs25-calreticulin interaction in vivo could represent a potential target for developing transmission blocking strategies based on interfering the parasite-midgut interaction.
Assuntos
Anopheles , Antígenos de Protozoários/metabolismo , Antígenos de Superfície/metabolismo , Calreticulina/metabolismo , Sistema Digestório , Insetos Vetores , Vacinas Antimaláricas/metabolismo , Plasmodium vivax/metabolismo , Sequência de Aminoácidos , Animais , Anopheles/genética , Anopheles/metabolismo , Anopheles/parasitologia , Antígenos de Protozoários/química , Antígenos de Protozoários/genética , Antígenos de Superfície/química , Antígenos de Superfície/genética , Sequência de Bases , Calreticulina/química , Calreticulina/genética , Homólogo 5 da Proteína Cromobox , Clonagem Molecular , Sistema Digestório/metabolismo , Sistema Digestório/parasitologia , Humanos , Insetos Vetores/genética , Insetos Vetores/metabolismo , Insetos Vetores/parasitologia , Vacinas Antimaláricas/química , Vacinas Antimaláricas/genética , Dados de Sequência Molecular , Plasmodium vivax/crescimento & desenvolvimento , Plasmodium vivax/fisiologia , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Análise de Sequência de DNARESUMO
The EtOAc extract of the stem bark of Hintonia latiflora showed the suppression of total parasitemia and the chemosuppression of schizont numbers, when tested in vivo against Plasmodium berghei infection in mice. Bioassay-directed fractionation of the EtOAc extract, using the in vitro 16 h and the in vivo 4-day suppression tests on P. berghei schizont numbers, led to the isolation of the new compound 5-O-beta-D-glucopyranosyl-7,4'-dimethoxy-3'-hydroxy-4-phenylcoumarin (1), along with the known 5-O-beta-D-glucopyranosyl-7-methoxy-3',4'-dihydroxy-4-phenylcoumarin (2). The structure of compound 1 was established on the basis of spectroscopic data interpretation. Compounds 1 and 2 suppressed the development of P. berghei schizonts in vitro with IC50 values of 24.7 and 25.9 microM, respectively. Compound 2 suppressed the development of schizonts at the dose of 40 mg/kg by 70.8% in the in vivo assay.
Assuntos
Antimaláricos , Cumarínicos , Plantas Medicinais/química , Rubiaceae/química , Animais , Antimaláricos/química , Antimaláricos/isolamento & purificação , Antimaláricos/farmacologia , Cumarínicos/química , Cumarínicos/isolamento & purificação , Cumarínicos/farmacologia , Concentração Inibidora 50 , México , Camundongos , Estrutura Molecular , Casca de Planta/química , Plasmodium berghei/efeitos dos fármacosRESUMO
Las infecciones de piel y tejido celular subcutáneo (IPSC) son entidades observadas frecuentemente en los servicios de atención médica, cuyo diagnóstico y tratamiento se basa en las caratcterísticas de las lesiones y el grado de compromiso de los tejidos. Estas infecciones incluyen una amplia variedad de presentaciones clínicas importantes de reconocer para su adecuado manejo. OBJETIVOS: Describir las características clínicas y epidemiológicas de las IPSC en un grupo de pacientes en el Hospital Nacional Cayetano Heredia (HNCH) entre 1994 y 1999. PACIENTES Y METODOS: Se condujo un estudio descriptivo de tipo transversal y retrospectivo por revisión de los registros de 82 pacientes adultos con IPSC reclutados en cuatro ensayos clínicos en el HNCH entre 1994 y 1999. RESULTADOS: Se incluyeron 82 pacientes evaluados por IPSC. La edad y el tiempo de enfermedad promedio fueron treinta y siete años y cuatro días respectivamente. 43,9 por ciento refirió un antecedente contributorio, específicamente un traumatismo en 41,6 por ciento de ellos. El 100 por ciento de los pacientes presentó dolor a la palpación y eritema. El diagnóstico de celulitis fue el más frecuente (63 por ciento), localizándose mayormente en miembros inferiores (p<0,01), el tiempo de enfermedad más corto correspondió a erisipela (p=0,03). La piodermitis se presentó más frecuentemente en varones (p=0,01). CONCLUSIONES: En menos del 50 por ciento de pacientes con IPSC se asociaron antecedentes contributorios, en todos se evidenció dolor y eritema. La celulitis fue la IPSC, encontrada con mayor frecuencia.
Assuntos
Humanos , Masculino , Adulto , Feminino , Dermatopatias , Celulite (Flegmão) , Erisipela , Estudos Transversais , Estudos Retrospectivos , Epidemiologia DescritivaRESUMO
El síndrome de secresión inapropiada de hormona antidiurética (SIADH) fue descubierto en 1957 y se le describió como un síndrome clínico caracterizado por hiponatremia, hiposmolaridad plasmática, pérdida renal de sodio y orina hiperosmolar con relación al plasma; asociado a diversas neoplasias, enfermedades infecciosas pulmonares y lesiones neurológicas. Por alta prevalencia del SIADH en pacientes de riesgo y el mal estado general la sintomatología de este síndrome podría ser atribuida a la enfermedad de fondo, no administrando el tratamiento adecuado y aumentando así la morbilidad de los pacientes. Se realiza una revisión de los criterios diagnósticos, los factores etiológicos, las manifestaciones clínicas, las diversas teorías que explican la fisiopatología del síndrome, el diagnóstico diferencial con otros tipos de hiponatremia y finalmente, el tratamiento sugerido.