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1.
J Virol ; 95(17): e0052321, 2021 08 10.
Artículo en Inglés | MEDLINE | ID: mdl-34132571

RESUMEN

Despite tight genetic compression, viral genomes are often organized into functional gene clusters, a modular structure that might favor their evolvability. This has greatly facilitated biotechnological developments such as the recombinant adeno-associated virus (AAV) systems for gene therapy. Following this lead, we endeavored to engineer the related insect parvovirus Junonia coenia densovirus (JcDV) to create addressable vectors for insect pest biocontrol. To enable safer manipulation of capsid mutants, we translocated the nonstructural (ns) gene cluster outside the viral genome. To our dismay, this yielded a virtually nonreplicable clone. We linked the replication defect to an unexpected modularity breach, as ns translocation truncated the overlapping 3' untranslated region (UTR) of the capsid transcript (vp). We found that the native vp 3' UTR is necessary for high-level VP production but that decreased expression does not adversely impact the expression of NS proteins, which are known replication effectors. As nonsense vp mutations recapitulate the replication defect, VP proteins appear to be directly implicated in the replication process. Our findings suggest intricate replication-encapsidation couplings that favor the maintenance of genetic integrity. We discuss possible connections with an intriguing cis-packaging phenomenon previously observed in parvoviruses whereby capsids preferentially package the genome from which they were expressed. IMPORTANCE Densoviruses could be used as biological control agents to manage insect pests. Such applications require an in-depth biological understanding and associated molecular tools. However, the genomes of these viruses remain difficult to manipulate due to poorly tractable secondary structures at their extremities. We devised a construction strategy that enables precise and efficient molecular modifications. Using this approach, we endeavored to create a split clone of Junonia coenia densovirus (JcDV) that can be used to safely study the impact of capsid mutations on host specificity. Our original construct proved to be nonfunctional. Fixing this defect led us to uncover that capsid proteins and their correct expression are essential for continued rolling-hairpin replication. This points to an intriguing link between replication and packaging, which might be shared with related viruses. This serendipitous discovery illustrates the power of synthetic biology approaches to advance our knowledge of biological systems.


Asunto(s)
Proteínas de la Cápside/metabolismo , Densovirus/fisiología , Genoma Viral , Infecciones por Parvoviridae/virología , Spodoptera/virología , Proteínas no Estructurales Virales/metabolismo , Replicación Viral , Regiones no Traducidas 3'/genética , Animales , Proteínas de la Cápside/genética , Vectores Genéticos , Control Biológico de Vectores , Proteínas no Estructurales Virales/genética
2.
Eur J Clin Invest ; 51(4): e13431, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33065765

RESUMEN

BACKGROUND: Atrial fibrillation (AF) and peripheral artery disease (PAD) are common conditions that increase cardiovascular risk. We determined the association between PAD and prognosis in a cohort of real-world patients receiving oral anticoagulant therapy for nonvalvular AF. METHODS: We prospectively included 1956 patients (mean age 73.8 ± 9.5 years, 44.0% women) receiving oral anticoagulant therapy for AF. Clinical characteristics were collected at baseline. Patients were followed for a period of 3 years. Survival analysis and multivariable regression analyses were performed to assess variables related to death, stroke, bleeding, myocardial infarction and major adverse cardiovascular events (MACE). RESULTS: Patients with PAD (n = 118; 6%) exhibited higher rates of cardiovascular risk factors and cardiovascular diseases. After 3 years of follow-up, there were a total of 255 deaths (no PAD 233, vs PAD 22), 45 strokes (43 vs 2), 146 major bleedings (136 vs 10) and 168 MACE (148 vs 20). On univariate analysis, there was a higher risk of cardiovascular mortality (2.02%/year no PAD vs 4.08%/year PAD, P = .02), myocardial infarction (0.99%/year no PAD vs 2.43%/year PAD, P = .02) and MACE (3.18%/year no PAD vs 6.99%/year PAD, P < .01). There was no statistically significant association with these events after multivariable adjustment. CONCLUSIONS: In a large cohort of anticoagulated patients with AF, the presence of PAD represents a higher risk subgroup and is associated with worse crude outcomes. The exact contribution of the PAD independently of other cardiovascular diseases or risk factors requires further investigation.


Asunto(s)
Anticoagulantes/uso terapéutico , Fibrilación Atrial/tratamiento farmacológico , Enfermedad Arterial Periférica/epidemiología , Accidente Cerebrovascular/prevención & control , Anciano , Anciano de 80 o más Años , Fibrilación Atrial/complicaciones , Fibrilación Atrial/epidemiología , Enfermedades Cardiovasculares/mortalidad , Comorbilidad , Femenino , Hemorragia/epidemiología , Humanos , Masculino , Persona de Mediana Edad , Infarto del Miocardio/epidemiología , Sistema de Registros , Accidente Cerebrovascular/epidemiología , Accidente Cerebrovascular/etiología
3.
J Low Genit Tract Dis ; 21(1): 73-77, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28027121

RESUMEN

OBJECTIVES: The aim of the study was to assess the 2 pathways of vulvar carcinogenesis and correlate immunohistochemical expression of p53 with histopathological findings. MATERIALS AND METHODS: This cross-sectional study included 76 cases. Patients were classified according to the 2004 International Society for the Study of Vulvovaginal Disease Terminology, followed by a review of clinical records and immunohistochemical staining for p53. RESULTS: Fifteen cases were in the human papillomavirus (HPV)-associated pathway (12 cases of usual vulvar intraepithelial neoplasia [VIN] and 3 of warty squamous cell carcinoma [SCC]), and 13 cases were in the HPV-independent pathway (5 cases of differentiated VIN and 8 of keratinizing SCC). Significant differences in p53 expression were observed between the 2 pathways of carcinogenesis: in the lesions related to the HPV-independent pathway, the percentage of p53-positive cells was greater (>25%, p < .001), and the staining pattern was basal (extending into the middle layer) in differentiated VIN and diffuse or infiltrative in warty SCC (p < 0.001). In the lesions HPV-associated pathway, p53 staining was less extensive (≤10% of cells, p < 0.001) and followed basal pattern in usual VIN, whereas warty SCCs were negative for p53 (p < 0.001). CONCLUSIONS: Unique patterns of histological appearance and p53 expression can separate vulvar lesions into 2 distinct pathways of carcinogenesis. We propose that p53 immunohistochemistry may be performed simultaneously with histopathological examination in all cases of VIN and vulvar SCC, because it would aid in definition of the pathway of carcinogenesis and thus enable better clinical follow-up of patients with these conditions.


Asunto(s)
Carcinogénesis , Carcinoma/patología , Carcinoma/fisiopatología , Proteína p53 Supresora de Tumor/análisis , Neoplasias de la Vulva/patología , Neoplasias de la Vulva/fisiopatología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Estudios Transversales , Femenino , Histocitoquímica , Humanos , Inmunohistoquímica , Persona de Mediana Edad , Adulto Joven
4.
PLoS Negl Trop Dis ; 18(3): e0011756, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38427694

RESUMEN

Rift Valley fever (RVF) is a mosquito-borne viral zoonosis caused by the Rift Valley fever virus (RVFV) that can infect domestic and wild animals. Although the RVFV transmission cycle has been well documented across Africa in savanna ecosystems, little is known about its transmission in tropical rainforest settings, particularly in Central Africa. We therefore conducted a survey in northeastern Gabon to assess RVFV circulation among wild and domestic animals. Among 163 wildlife samples tested using RVFV-specific RT-qPCR, four ruminants belonging to subfamily Cephalophinae were detected positive. The phylogenetic analysis revealed that the four RVFV sequences clustered together with a virus isolated in Namibia within the well-structured Egyptian clade. A cross-sectional survey conducted on sheep, goats and dogs living in villages within the same area determined the IgG RVFV-specific antibody prevalence using cELISA. Out of the 306 small ruminants tested (214 goats, 92 sheep), an overall antibody prevalence of 15.4% (95% CI [11.5-19.9]) was observed with a higher rate in goats than in sheep (20.1% versus 3.3%). RVFV-specific antibodies were detected in a single dog out of the 26 tested. Neither age, sex of domestic animals nor season was found to be significant risk factors of RVFV occurrence. Our findings highlight sylvatic circulation of RVFV for the first time in Gabon. These results stress the need to develop adequate surveillance plan measures to better control the public health threat of RVFV.


Asunto(s)
Fiebre del Valle del Rift , Virus de la Fiebre del Valle del Rift , Animales , Ovinos , Perros , Animales Domésticos , Animales Salvajes , Gabón/epidemiología , Estudios Transversales , Ecosistema , Filogenia , Rumiantes , Cabras , Anticuerpos Antivirales , Bosques , Estudios Seroepidemiológicos
5.
Animals (Basel) ; 13(15)2023 Aug 03.
Artículo en Inglés | MEDLINE | ID: mdl-37570320

RESUMEN

Astroviruses (AstVs), enteroviruses (EVs), and caliciviruses (CaVs) infect several vertebrate taxa. Transmitted through the fecal-oral route, these enteric viruses are highly resistant and can survive in the environment, thereby increasing their zoonotic potential. Here, we screened for AstVs, EVs, and CaVs to investigate the role of domestic animals in the emergence of zoonoses, because they are situated at the human/wildlife interface, particularly in rural forested areas in Central Africa. Rectal swabs were obtained from 123 goats, 41 sheep, and 76 dogs in 10 villages located in northeastern Gabon. Extracted RNA reverse-transcribed into cDNA was used to detect AstVs, EVs, and CaVs by amplification of the RNA-dependent RNA polymerase (RdRp), or capsid protein (VP1) gene using PCR. A total of 23 samples tested positive, including 17 goats for AstVs, 2 goats, 2 sheep, 1 dog for EVs, and 1 dog for CaVs. Phylogenetic analyses revealed that AstV RdRp sequences clustered with sheep-, goat-, or bovine-related AstVs. In addition, one goat and two sheep VP1 sequences clustered with caprine/ovine-related Evs within the Enterovirus G species, and the CaV was a canine vesivirus. However, human-pathogenic Evs, EV-B80 and EV-C99, were detected in goats and dogs, raising questions on the maintenance of viruses able to infect humans.

6.
Vet Sci ; 9(2)2022 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-35202302

RESUMEN

We tested 144 pet rabbits sampled in France between November 2020 and June 2021 for antibodies to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) by microsphere immunoassay. We reported the first evidence of a natural SARS-CoV-2 infection in rabbits with a low observed seroprevalence between 0.7% and 1.4%.

7.
J Biomed Biotechnol ; 2010: 752698, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20145711

RESUMEN

Extracellular factors produced by Leishmania spp., Trypanosoma cruzi, and Trypanosoma brucei are important in the host-parasite relationship. Here, we describe a genome-based approach to identify putative extracellular proteins conserved among trypanosomatids that are likely involved in the classical secretory pathway. Potentially secreted proteins were identified by bioinformatic analysis of the T. cruzi genome. A subset of thirteen genes encoding unknown proteins with orthologs containing a signal peptide sequence in L. infantum, L. major, and T. brucei were transfected into L. infantum. Tagged proteins detected in the extracellular medium confirmed computer predictions in about 25% of the hits. Secretion was confirmed for two L. infantum orthologs proteins using the same experimental system. Infectivity studies of transgenic Leishmania parasites suggest that one of the secreted proteins increases parasite replication inside macrophages. This methodology can identify conserved secreted proteins involved in the classical secretory pathway, and they may represent potential virulence factors in trypanosomatids.


Asunto(s)
Biología Computacional/métodos , Genoma de Protozoos , Proteínas Protozoarias/genética , Trypanosomatina/genética , Células Cultivadas , Simulación por Computador , Secuencia Conservada , Humanos , Macrófagos/parasitología , Proteínas Protozoarias/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Estadísticas no Paramétricas , Trypanosomatina/crecimiento & desarrollo , Factores de Virulencia
8.
J Immunol ; 181(4): 2887-97, 2008 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-18684980

RESUMEN

We analyzed reconstitution characteristics of plasmacytoid dendritic cells (PDCs) and myeloid DCs-1 in 38 HIV-1-infected patients with impaired restoration of CD4 T cell counts despite prolonged suppression of plasma viremia (discordant) and compared them with 42 patients showing good immunological and virological responses following highly active antiretroviral therapy (HAART). While myeloid DCs showed spontaneous recovery following HAART in both the groups, the discordant patients demonstrated poor peripheral reconstitution of PDCs as compared with concordant patients. The ability of PDCs to produce IFN-alpha following stimulation with TLR7 ligand imiquimod and TLR9 ligand CpG ODN-2216 was also impaired in discordant patients even after 2 years following initiation of HAART. Lower IFN-alpha expression in the PDCs following TLR stimulation was further associated with lower expression of transcription factor, IFN regulatory factor-7. In contrast, production of TNF-alpha and IL-6 following TLR stimulation was comparable in both groups of patients, indicating that impaired reconstitution characteristics do not affect the capacity of PDCs to produce proinflammatory cytokines. The discordant patients had significantly lower baseline CD4 T cell counts and higher baseline viral load at the initiation of HAART implying that lower baseline CD4 T cell counts and higher plasma viral load are associated with impaired restoration of CD4 T cells and PDCs, thus, increasing the susceptibility of discordant patients toward opportunistic infections despite virological control.


Asunto(s)
Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD4-Positivos/patología , Citocinas/biosíntesis , Células Dendríticas/inmunología , Células Dendríticas/virología , Infecciones por VIH/inmunología , Mediadores de Inflamación/metabolismo , Interferón-alfa/biosíntesis , Adulto , Anciano , Terapia Antirretroviral Altamente Activa , Recuento de Linfocito CD4 , Linfocitos T CD4-Positivos/efectos de los fármacos , Linfocitos T CD4-Positivos/virología , Células Cultivadas , Citocinas/fisiología , Células Dendríticas/efectos de los fármacos , Células Dendríticas/metabolismo , Femenino , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/patología , Infecciones por VIH/virología , VIH-1/efectos de los fármacos , VIH-1/genética , Humanos , Mediadores de Inflamación/fisiología , Interferón-alfa/antagonistas & inhibidores , Masculino , Persona de Mediana Edad , ARN Viral/biosíntesis , Carga Viral
9.
Microorganisms ; 8(7)2020 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-32640689

RESUMEN

Zoonotic cutaneous leishmaniasis (ZCL) caused by Leishmania major Yakimoff & Shokhor and transmitted by Phlebotomus papatasi (Scopoli) is a public health concern in Morocco. The disease is endemic mainly in pre-Saharan regions on the southern slope of the High Atlas Mountains. The northern slope of the High Atlas Mountains and the arid plains of central Morocco remain non-endemic and are currently considered high risk for ZCL. Here we investigate and compare the population genetic structure of P. papatasi populations sampled in various habitats in historical foci and non-endemic ZCL areas. A fragment of the mtDNA cytochrome oxidase I (CO1) gene was amplified and sequenced in 59 individuals from 10 P. papatasi populations. Haplotype diversity was probed, a median-joining network was generated (FST) and molecular variance (AMOVA) were analyzed. Overall, we identified 28 haplotypes with 32 distinct segregating sites, of which seven are parsimony informative. The rate of private haplotypes was high; 20 haplotypes (71.4%) are private ones and exclusive to a single population. The phylogenetic tree and the network reconstructed highlight a genetic structuration of these populations in two well defined groups: Ouarzazate (or endemic areas) and Non-Ouarzazate (or nonendemic areas). These groups are separated by the High Atlas Mountains. Overall, our study highlights differences in terms of population genetics between ZCL endemic and non-endemic areas. To what extent such differences would impact the transmission of L. major by natural P. papatasi population remains to be investigated.

10.
Emerg Microbes Infect ; 8(1): 1003-1016, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31282298

RESUMEN

Zika virus (ZIKV) is a mosquito-borne Flavivirus that causes Zika disease with particular neurological complications, including Guillain-Barré Syndrome and congenital microcephaly. Although ZIKV has been shown to directly infect human neural progenitor cells (hNPCs), thereby decreasing their viability and growth, it is as yet unknown which of the cellular pathways involved in the disruption of neurogenesis are affected following ZIKV infection. By comparing the effect of two ZIKV strains in vitro on hNPCs, the differentiation process of the latter cells was found to lead to a decreased susceptibility to infection and cell death induced by each of the ZIKV strains, which was associated with an earlier and stronger antiviral innate immune response in infected, differentiated hNPCs, as compared to undifferentiated cells. Moreover, ZIKV modulated, both in hNPCs and in vivo in fetal brain in an experimental mouse model, the expression of the Notch pathway which is involved in cellular proliferation, apoptosis and differentiation during neurogenesis. These results show that the differentiation state of hNPCs is a significant factor contributing to the outcome of ZIKV infection and furthermore suggest that ZIKV infection might initiate early activation of the Notch pathway resulting in an abnormal differentiation process, implicated in ZIKV-induced brain injury.


Asunto(s)
Células-Madre Neurales/virología , Neurogénesis , Receptor Notch1/metabolismo , Infección por el Virus Zika/virología , Virus Zika/fisiología , Animales , Apoptosis , Femenino , Humanos , Ratones , Células-Madre Neurales/citología , Células-Madre Neurales/metabolismo , Receptor Notch1/genética , Transducción de Señal , Virus Zika/genética , Infección por el Virus Zika/genética , Infección por el Virus Zika/metabolismo , Infección por el Virus Zika/fisiopatología
11.
Infect Genet Evol ; 49: 134-137, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-28095299

RESUMEN

ZIKA virus (ZIKV) is a newly emerging arbovirus. Since its discovery 60years ago in Uganda, it has spread throughout the Pacific, Latin America and the Caribbean, emphasizing the capacity of ZIKV to spread to non-endemic regions worldwide. Although infection with ZIKV often leads to mild disease, its recent emergence in the Americas has coincided with an increase in adults developing Guillain-Barré syndrome and neurological complications in new-borns, such as congenital microcephaly. Many questions remain unanswered regarding the complications caused by different primary isolates of ZIKV. Here, we report the permissiveness of primary human astrocytes for two clinically relevant, Asian and African ZIKV strains and show that both isolates strongly induce antiviral immune responses in these cells albeit with markedly different kinetics. This study describes for the first time the specific antiviral gene expression in infected primary human astrocytes, the major glial cells within the central nervous system.


Asunto(s)
Astrocitos/inmunología , Proteína 58 DEAD Box/inmunología , Interacciones Huésped-Patógeno , Proteínas NLR/inmunología , Receptores Toll-Like/inmunología , Astrocitos/virología , Proteína 58 DEAD Box/genética , Regulación de la Expresión Génica , Humanos , Inmunidad Innata , Proteínas NLR/genética , Cultivo Primario de Células , ARN Viral/biosíntesis , ARN Viral/genética , Receptores Inmunológicos , Factores de Tiempo , Receptores Toll-Like/genética , Carga Viral/inmunología , Replicación Viral/inmunología , Virus Zika/genética , Virus Zika/crecimiento & desarrollo
12.
Psychopharmacology (Berl) ; 175(2): 154-62, 2004 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-14985920

RESUMEN

RATIONALE: Cocaine-seeking behavior can be investigated in rodents using the conditioned place preference (CPP) paradigm, in which the drug-paired environment serves as a conditioned stimulus. Such approach allowed to previously demonstrate the importance of the neuromodulatory sigma1 (sigma1) receptor in acquisition of cocaine-induced CPP. CPP can be extinguished and then reactivated, notably using a cocaine challenge (i.e., priming). OBJECTIVES AND METHODS: In order to examine the role of the sigma1 receptor in reinstatement of Cocaine-seeking, Swiss mice acquired CPP with cocaine (30 mg/kg, i.p.) and then CPP was extinguished. RESULTS: A challenge cocaine priming (15 mg/kg) reactivated CPP up to 140% of the post-conditioning response. Pre-administration of the sigma1 receptor antagonist BD1047 (330 mg/kg, i.p.) or repeated treatment with an antisense probe targeting the sigma1 receptor prevented CPP reactivation. The sigma1 agonist igmesine (1-10 mg/kg, i.p.) or the steroid dehydroepiandrosterone (DHEA, 10-40 mg/kg, s.c.) reactivated CPP, in a BD1047-sensitive manner. Moreover, the in vivo [3H](+)-SKF-10,047 binding levels to the sigma1 receptor were increased after cocaine conditioning in numerous brain structures and these increases subsisted after extinction. Finally, cross-reactivation of cocaine-induced CPP was observed after phencyclidine (PCP), morphine, nicotine and ethanol administration. However, BD1047 blocked reactivation of CPP induced by PCP, morphine and nicotine but not ethanol. CONCLUSIONS: Since activation of the sigma1 receptor is not sufficient to sustain CPP in naive animals [Neuropsychopharmacology 26 (2002) 444], it is concluded that sigma1 receptor activation is a key event for relapse to drug seeking. Activation may occur via sensitization due to enhanced in vivo available of receptors.


Asunto(s)
Anestésicos Locales/farmacología , Conducta Animal/efectos de los fármacos , Cocaína/farmacología , Etilenodiaminas/farmacología , Receptores sigma/antagonistas & inhibidores , Adyuvantes Inmunológicos/farmacología , Animales , Sitios de Unión , Cinamatos/farmacología , Ciclopropanos/farmacología , Deshidroepiandrosterona/farmacología , Interacciones Farmacológicas , Masculino , Ratones , Receptores sigma/agonistas , Receptores sigma/metabolismo
13.
PLoS Negl Trop Dis ; 8(5): e2850, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24831235

RESUMEN

Intracellular protozoan parasites are causative agents of infectious diseases that constitute major health problems for developing countries. Leishmania sp., Trypanosoma cruzi or Toxoplasma gondii are all obligate intracellular protozoan parasites that reside and multiply within the host cells of mammals, including humans. Following up intracellular parasite proliferation is therefore an essential and a quotidian task for many laboratories working on primary screening of new natural and synthetic drugs, analyzing drug susceptibility or comparing virulence properties of natural and genetically modified strains. Nevertheless, laborious manual microscopic counting of intracellular parasites is still the most commonly used approach. Here, we present INsPECT (Intracellular ParasitE CounTer), an open-source and platform independent software dedicated to automate infection level measurement based on fluorescent DNA staining. It offers the possibility to choose between different types of analyses (fluorescent DNA acquisitions only or in combination with phase contrast image set to further separate intra- from extracellular parasites), and software running modes (automatic or custom). A proof-of-concept study with intracellular Leishmania infantum parasites stained with DAPI (4',6-diamidino-2-phenylindole) confirms a good correspondence between digital results and the "gold standard" microscopic counting method with Giemsa. Interestingly, this software is versatile enough to accurately detect intracellular T. gondii parasites on images acquired with High Content Screening (HCS) systems. In conclusion, INsPECT software is proposed as a new fast and simple alternative to the classical intracellular Leishmania quantification methods and can be adapted for mid to large-scale drug screening against different intracellular parasites.


Asunto(s)
Técnicas Citológicas/métodos , Procesamiento de Imagen Asistido por Computador/métodos , Espacio Intracelular/parasitología , Leishmania/aislamiento & purificación , Parasitología/métodos , Programas Informáticos , Algoritmos , Línea Celular , Fibroblastos/citología , Fibroblastos/parasitología , Humanos , Microscopía Fluorescente , Reproducibilidad de los Resultados
14.
Toxicol Sci ; 139(1): 245-56, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24519524

RESUMEN

Phototoxic properties of systemically applied pharmaceuticals may be the cause of serious adverse drug reactions. Therefore, a reliable preclinical photosafety assessment strategy, combining in vitro and in vivo approaches in a quantitative manner, is important and has not been described so far. Here, we report the establishment of an optimized modified murine local lymph node assay (LLNA), adapted for phototoxicity assessment of systemically applied compounds, as well as the test results for 34 drug candidates in this in vivo photo-LLNA. The drug candidates were selected based on their ability to absorb ultraviolet/visible light and the photo irritation factors (PIFs) determined in the well-established in vitro 3T3 neutral red uptake phototoxicity test. An in vivo phototoxic potential was identified for 13 of these drug candidates. The use of multiple dose levels in the described murine in vivo phototoxicity studies enabled the establishment of no- and/or lowest-observed-adverse-effect levels (NOAELs/LOAELs), also supporting human photosafety assessment. An in vitro-in vivo correlation demonstrated that a drug candidate classified as "phototoxic" in vitro is not necessarily phototoxic in vivo. However, the probability for a drug candidate to cause phototoxicity in vivo clearly correlated with the magnitude of the phototoxicity identified in vitro.


Asunto(s)
Dermatitis Fototóxica , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos , Pruebas de Toxicidad/métodos , Animales , Evaluación Preclínica de Medicamentos , Femenino , Ganglios Linfáticos/efectos de los fármacos , Ratones , Ratones Endogámicos BALB C , Espectrofotometría Ultravioleta
15.
Int J Parasitol ; 42(4): 323-7, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22619752

RESUMEN

Leishmania infantum nicotinamidase, encoded by the Lipnc1 gene, converts nicotinamide into nicotinicacid to ensure Nicotinamide­Adenine­Dinucleotide (NAD+) biosynthesis. We were curious to explore the role of this enzyme during L. infantum development in its natural sand fly vector, Phlebotomus perniciosus (Diptera, Phlebotominae), using null mutants with a deleted Lipnc1 gene. The null mutants developed as well as the wild type L. infantum at the early time points post their ingestion within the bloodmeal. In contrast, once the blood meal digestion was completed, the null mutants were unable to develop further and establish late-stage infections. Data highlight the importance of the nicotinamide degradation pathway for Leishmania development in sand flies. They indicate that the endogenous nicotinamidase is essential for Leishmania development in the sand fly after the blood meal has been digested and the remnants defecated.


Asunto(s)
Leishmania infantum/enzimología , Leishmania infantum/crecimiento & desarrollo , Nicotinamidasa/metabolismo , Phlebotomus/parasitología , Animales , Femenino , Eliminación de Gen , Leishmania infantum/genética , NAD/metabolismo , Niacina/metabolismo , Niacinamida/metabolismo , Nicotinamidasa/deficiencia , Nicotinamidasa/genética
16.
Parasitol Int ; 60(1): 19-24, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-20884376

RESUMEN

To improve the management of leishmaniasis, new drugs and/or alternative therapeutic strategies are required. Combination therapy of antileishmanial drugs is currently considered as one of the most rational approaches to lower treatment failure rate and limit drug resistance spreading. Nicotinamide (NAm), also known as vitamin B3 that is already is used in human therapy, exerts in vitro antileishmanial activity. Drug combination studies, performed on L. infantum axenic amastigotes, revealed that NAm significantly improves the antileishmanial activity of trivalent antimony in a synergistic manner while it shows additive activity with amphotericin B and slightly antagonizes pentamidine activity. NAm also significantly increases the toxicity of pentavalent antimony against the intracellular forms of L. infantum, L. amazonensis and L. braziliensis. The potential of NAm to be used as adjuvant during leishmaniasis chemotherapy is further discussed.


Asunto(s)
Anfotericina B/farmacología , Antimonio/farmacología , Antiprotozoarios/farmacología , Leishmaniasis/tratamiento farmacológico , Niacinamida/farmacología , Línea Celular , Fragmentación del ADN , Combinación de Medicamentos , Resistencia a Medicamentos , Citometría de Flujo , Humanos , Leishmania infantum/efectos de los fármacos , Pruebas de Sensibilidad Parasitaria , Pentamidina/antagonistas & inhibidores
17.
Rev. cuba. hematol. inmunol. hemoter ; 27(2): 224-232, abr.-jun. 2011.
Artículo en Español | CUMED | ID: cum-61211

RESUMEN

Las células del trofoblasto no expresan los antígenos HLA clásicos de clase I (A, B, C), pero sí los antígenos HLA G que pueden generar anticuerpos capaces de tener reacción cruzada con los primeros. Se estudiaron 24 mujeres en el primer trimestre del embarazo, sin antecedentes de embarazos o transfusiones de sangre, con anticuerpos reactivos contra leucocitos, plaquetas o ambos (9 antigranulocitarios y 15 anti-HLA), para determinar la presencia de anticuerpos antitrofoblasto, mediante técnica de inmunofluorescencia indirecta en lámina. El 54,16 por ciento presentó anticuerpos antitrofoblasto. El 86,66 por ciento de las embarazadas con anticuerpos anti-HLA, presentó anticuerpos contra trofoblasto, mientras que ninguno de los sueros con anticuerpos específicos de granulocitos reaccionó con las células trofoblásticas (p=0,00). Después de la adsorción con tejido trofoblástico, los sueros con anticuerpos con especificidad granulocitaria mantuvieron la reactividad con leucocitos de sangre periférica, y solo 2 de los que presentaban especificidad HLA. Los resultados sugieren que la mayoría de los anticuerpos anti-HLA, reactivos con leucocitos, plaquetas o ambos, pueden estar dirigidos contra antígenos HLA-G del trofoblasto y muestran reacción cruzada con los antígenos HLA leucocitarios, lo cual favorece el bloqueo de la respuesta de los leucocitos maternos contra las células fetales, lo que pudiera explicar, además, la alta prevalencia de anticuerpos anti-HLA en el embarazo temprano(AU)


Trophoblast cells do not express classical HLA class I antigens (A, B, C), but they do express HLA G antigens which may generate antibodies capable of cross-reacting with the former. A study was conducted of 24 women in the first quarter of pregnancy, with no previous pregnancies or blood transfusions, with reactive antibodies against leukocytes, platelets or both (9 antigranulocytary and 15 anti-HLA), to determine the presence of antitrophoblast antibodies, by plate indirect immunofluorescence technique. 54.16 percent had antitrophoblast antibodies. 86.66 percent of the pregnant women with anti-HLA antibodies had antibodies against the trophoblast, whereas none of the sera with granulocyte specific antibodies reacted with trophoblastic cells (p=0,00). Following adsorption with trophoblastic tissue, the sera with antibodies showing granulocyte specificity remained reactive with peripheral blood leukocytes, as opposed to just 2 of those showing HLA specificity. Results suggest that most anti-HLA antibodies reactive with leukocytes, platelets or both, may be aimed against trophoblast HLA-G antigens, and cross-react with leukocyte HLA antigens, which facilitates blockage of the response of maternal leukocytes against fetal cells. This may also explain the high prevalence of anti-HLA antibodies during early pregnancy(AU)


Asunto(s)
Humanos , Femenino , Embarazo , Trofoblastos , Reacciones Antígeno-Anticuerpo/inmunología , Primer Trimestre del Embarazo/inmunología , Antígenos HLA
18.
Rev. cuba. hematol. inmunol. hemoter ; 27(2): 224-232, abr.-jun. 2011.
Artículo en Español | LILACS | ID: lil-615349

RESUMEN

Las células del trofoblasto no expresan los antígenos HLA clásicos de clase I (A, B, C), pero sí los antígenos HLA G que pueden generar anticuerpos capaces de tener reacción cruzada con los primeros. Se estudiaron 24 mujeres en el primer trimestre del embarazo, sin antecedentes de embarazos o transfusiones de sangre, con anticuerpos reactivos contra leucocitos, plaquetas o ambos (9 antigranulocitarios y 15 anti-HLA), para determinar la presencia de anticuerpos antitrofoblasto, mediante técnica de inmunofluorescencia indirecta en lámina. El 54,16 por ciento presentó anticuerpos antitrofoblasto. El 86,66 por ciento de las embarazadas con anticuerpos anti-HLA, presentó anticuerpos contra trofoblasto, mientras que ninguno de los sueros con anticuerpos específicos de granulocitos reaccionó con las células trofoblásticas (p=0,00). Después de la adsorción con tejido trofoblástico, los sueros con anticuerpos con especificidad granulocitaria mantuvieron la reactividad con leucocitos de sangre periférica, y solo 2 de los que presentaban especificidad HLA. Los resultados sugieren que la mayoría de los anticuerpos anti-HLA, reactivos con leucocitos, plaquetas o ambos, pueden estar dirigidos contra antígenos HLA-G del trofoblasto y muestran reacción cruzada con los antígenos HLA leucocitarios, lo cual favorece el bloqueo de la respuesta de los leucocitos maternos contra las células fetales, lo que pudiera explicar, además, la alta prevalencia de anticuerpos anti-HLA en el embarazo temprano


Trophoblast cells do not express classical HLA class I antigens (A, B, C), but they do express HLA G antigens which may generate antibodies capable of cross-reacting with the former. A study was conducted of 24 women in the first quarter of pregnancy, with no previous pregnancies or blood transfusions, with reactive antibodies against leukocytes, platelets or both (9 antigranulocytary and 15 anti-HLA), to determine the presence of antitrophoblast antibodies, by plate indirect immunofluorescence technique. 54.16 percent had antitrophoblast antibodies. 86.66 percent of the pregnant women with anti-HLA antibodies had antibodies against the trophoblast, whereas none of the sera with granulocyte specific antibodies reacted with trophoblastic cells (p=0,00). Following adsorption with trophoblastic tissue, the sera with antibodies showing granulocyte specificity remained reactive with peripheral blood leukocytes, as opposed to just 2 of those showing HLA specificity. Results suggest that most anti-HLA antibodies reactive with leukocytes, platelets or both, may be aimed against trophoblast HLA-G antigens, and cross-react with leukocyte HLA antigens, which facilitates blockage of the response of maternal leukocytes against fetal cells. This may also explain the high prevalence of anti-HLA antibodies during early pregnancy

19.
Mundo saúde (Impr.) ; 34(3): 327-335, jul.-set. 2010.
Artículo en Portugués | LILACS | ID: lil-590547

RESUMEN

O objetivo deste trabalho foi descrever um projeto para ensinar valores fundamentais da Medicina de Família, num contexto de visitas domiciliares a crianças com doenças crônicas. Estudantes de medicina acompanharam médico de família da SOBRAMFA (Sociedade Brasileira de Medicina de Família), em visitas domiciliares a crianças com doenças crônicas e relataram seus pontos de vista através de uma narrativa descritiva. Os relatórios dos estudantes foram avaliados através de uma abordagem qualitativa. O estudo revelou que os estudantes de medicina envolvidos neste projeto obtiveram uma ampla perspectiva sobre a complexidade do cuidar de crianças com doenças crônicas. Aspectos emocionais, a dinâmica familiar, o ambiente doméstico, a dor e a angústia que as famílias sofrem para desativar as barreiras a fim de obter medicamentos específicos, juntamente com problemas financeiros, são retratados todos juntos em cada visita domiciliar. Os alunos percebem que precisam lidar com todas essas questões para obter uma assistência mais eficaz e compassiva. Entendem, ainda, que as visitas domiciliares têm alta eficácia clínica, uma vez que os pacientes permanecem em seus domicílios e são menos hospitalizados. Uma proposta projetada para ensinar estudantes de medicina ao ver crianças com doenças crônicas em visitas domiciliares com médicos de família é um cenário de ensino útil, porque revela os aspectos insuspeitados e essenciais ao próprio doutorando e o introduz aos valores centrais da Medicina de Família.


This work aims to describe a project for teaching basic values of Family Medicine, in a context of home visits to children with chronic diseases. Medical students accompanied a family doctor of SOBRAMFA (Brazilian Society of Family Medicine) in home visits to children with chronic diseases and reported their points of view through a descriptive narrative. The reports were evaluated using a qualitative approach. The study showed that medical students participating in this project managed to build a broader perspective on the complexity of caring for children with chronic diseases. Emotional aspects, family dynamics, the home environment, the pain and the anguish that families suffer to surmount obstacles in orderto obtain specific medicines, together with financial problems, are shown to be correlated in each home visit. Students realize that they need to deal with all these questions to offer a more efficient and compassionate presence as doctors. They also understand that home visits have a high clinical efficiency because patients remain in their homes and are less hospitalized. A proposal for teaching medical students in visits to children with chronic diseases together with family doctors is a useful teaching setting because it reveals unsuspected and essential aspects to medical student sand introduces them to the central values of Family Medicine.


El objetivo de este trabajo ha sido describir un proyecto para enseñar valores fundamentales de la Medicina de Familia, en un contexto de visitas domiciliarias a niños con enfermedades crónicas. Algunos alumnos de medicina han acompañado a un médico de família de la SOBRAMFA (Sociedad Brasileña de Medicina de Familia) en visitas domiciliarias a niños con enfermedades crónicas y relataron sus puntos de vista por medio de una narrativa descritiva. Los informes de los estudiantes han sido evaluados por medio de un abordaje cualitativo. El estudio ha revelado que los alumnos de medicina envolucrados en ese proyecto han logrado una amplia perspectiva acerca de la complejidad del cuidar de niños con enfermedades crónicas. Aspectos emocionales, la dinámica familiar, el ambiente doméstico, el dolor y la angustia que las familias sufren para desactivar lasbarreras a fin de obtener medicamentos específicos, al lado de los problemas financieros, son retractados en conjunto en cada visita domiciliaria. Los alumnos perciben que necesitan manejarse con todas esas cuestiones para obtener una asistencia más eficaz y compasiva. Ellos perciben también que las visitas domiciliarias tienen una alta eficacia clínica, porque los pacientes permanecen en sus domicilios y son menos hospitalizados. Una propuesta proyectada para enseñar alumnos de medicina cuando ven niños con enfermedades crónicas en visitas domiciliarias con médicos de familia es un escenario de enseñanza útil, dado que revela los aspectos insospechados y esenciales al propio doctorando y lo introduce en los valores centrales de la medicina de familia.


Asunto(s)
Niño , Cuidado del Niño , Enfermedad Crónica , Servicios de Atención de Salud a Domicilio , Medicina Familiar y Comunitaria
20.
Mundo saúde (Impr.) ; 34(3): 395-403, jul.-set. 2010.
Artículo en Portugués | LILACS | ID: lil-590538

RESUMEN

O 14º Congresso da SOBRAMFA foi introduzido por uma sessão de narrativas, a qual ocorreu antes mesmo de sua abertura oficial. Esta atividade representou uma oportunidade para que os participantes – médicos e estudantes de Medicina – pudessem compartilhar histórias emergentes do ensino e da prática da Medicina. Narrativas comoventes ou ilustrativas foram apresentadas e ficou demonstrado que o contador de histórias que existe no interior de cada ser humano não morreu. A prática da Medicina em sua total magnitude, ou seja, como Ciência e Arte, não ignora as histórias vividas e contadas por médicos, pacientes, estudantes e professores. Este evento informal nos ajudou a compreender o motivo pelo qual as narrativas, cada vez mais, têm sido utilizadas como instrumento terapêutico, paliativo e didático.


The 14th Congress of SOBRAMFA began with a session of narratives, which took place before the official opening. This activity was an opportunity for participants – doctors and medical students – to share emergent histories of teaching and the practice of Medicine. Moving or illustrative narratives were presented and it was demonstrated that the storyteller that exists inside each human being has not died. The practice of Medicine in its full magnitude, in other words, as Science and Art, does not ignore the stories experienced in life and told by doctors, patients, students and teachers. This informal event helped understanding the reason why narratives are being increasingly used as a therapeutic, palliative and educational instrument.


El 14º Congreso de SOBRAMFA comenzó con una sesión de narrativas, que ocurrieron antes de la apertura oficial. Esa actividad fue una oportunidad para participantes – doctores y estudiantes médicos – compartir historias emergentes de la enseñanza y la práctica de la Medicina. Se presentaran narrativas emocionantes e ilustrativas y se demostraran que el cuentista que existe dentro de cada ser humano no se ha muerto. La práctica de la Medicina en su llena magnitud, en otras palabras, como Ciencia y Arte, no ignora las historias experimentadas en la vida y narradas por doctores, pacientes, estudiantes y profesores. Este acontecimiento informal ayudó al entendimiento de la razón por qué las narrativas están siendo cada vez más usadas como un instrumento terapéutico, paliativo y educativo.


Asunto(s)
Humanos , Autobiografía , Medicina , Medicina Familiar y Comunitaria
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