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1.
Parasitology ; 151(5): 506-513, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38533610

RESUMEN

Leishmania is a trypanosomatid parasite that causes skin lesions in its cutaneous form. Current therapies rely on old and expensive drugs, against which the parasites have acquired considerable resistance. Trypanosomatids are unable to synthesize purines relying on salvaging from the host, and nucleoside analogues have emerged as attractive antiparasitic drug candidates. 4-Methyl-7-ß-D-ribofuranosyl-7H-pyrrolo[2,3-d]pyrimidine (CL5564), an analogue of tubercidin in which the amine has been replaced by a methyl group, demonstrates activity against Trypanosoma cruzi and Leishmania infantum. Herein, we investigated its in vitro and in vivo activity against L. amazonensis. CL5564 was 6.5-fold (P = 0.0002) more potent than milteforan™ (ML) against intracellular forms in peritoneal mouse macrophages, and highly selective, while combination with ML gave an additive effect. These results stimulated us to study the activity of CL5564 in mouse model of cutaneous Leishmania infection. BALB/c female and male mice infected by L. amazonensis treated with CL5564 (10 mg kg−1, intralesional route for five days) presented a >93% reduction of paw lesion size likely ML given orally at 40 mg kg−1, while the combination (10 + 40 mg kg−1 of CL5564 and ML, respectively) caused >96% reduction. The qPCR confirmed the suppression of parasite load, but only the combination approach reached 66% of parasitological cure. These results support additional studies with nucleoside derivatives.


Asunto(s)
Modelos Animales de Enfermedad , Leishmania mexicana , Leishmaniasis Cutánea , Ratones Endogámicos BALB C , Animales , Leishmaniasis Cutánea/tratamiento farmacológico , Leishmaniasis Cutánea/parasitología , Ratones , Femenino , Masculino , Leishmania mexicana/efectos de los fármacos , Tubercidina/farmacología , Tubercidina/análogos & derivados , Antiprotozoarios/farmacología , Antiprotozoarios/uso terapéutico , Antiprotozoarios/administración & dosificación , Macrófagos Peritoneales/parasitología , Macrófagos Peritoneales/efectos de los fármacos , Leishmania/efectos de los fármacos
2.
Exp Parasitol ; 262: 108787, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38759776

RESUMEN

New affordable drugs are needed for the treatment of infection with the protozoan parasite Trypanosoma cruzi responsible for the Chagas disease (CD). Only two old drugs are currently available, nifurtimox and benznidazole (Bz) but they exhibit unwanted side effects and display a weak activity in the late chronic phase of the disease. In this context, we evaluated the activity of a series of aryl-pyrazolone derivatives against T cruzi, using both bloodstream trypomastigote and intracellular amastigote forms of the parasite. The test compounds originate from a series of anticancer agents targeting the immune checkpoint ligand PD-L1 and bear an analogy with known anti-trypanosomal pyrazolones. A first group of 6 phenyl-pyrazolones was tested, revealing the activity of a single pyridyl-pyrazolone derivative. Then a second group of 8 compounds with a common pyridyl-pyrazolone core was evaluated. The in vitro testing process led to the identification of two non-cytotoxic and highly potent molecules against the intracellular form of T. cruzi, with an activity comparable to Bz. Moreover, one compound revealed an activity largely superior to that of Bz against bloodstream trypomastigotes, while being non-cytotoxic (selectivity index >1000). Unfortunately, the compound showed little activity in vivo, most likely due to its very limited plasma stability. However, the study opens novel perspectives for the design of new anti-trypanosomal products and the mechanism of action of the compounds is discussed.


Asunto(s)
Enfermedad de Chagas , Pirazolonas , Tripanocidas , Trypanosoma cruzi , Trypanosoma cruzi/efectos de los fármacos , Pirazolonas/farmacología , Pirazolonas/química , Tripanocidas/farmacología , Tripanocidas/química , Animales , Ratones , Enfermedad de Chagas/tratamiento farmacológico , Enfermedad de Chagas/parasitología , Piridinas/farmacología , Piridinas/química , Concentración 50 Inhibidora , Nitroimidazoles/farmacología , Nitroimidazoles/química
3.
Int J Mol Sci ; 23(23)2022 Nov 24.
Artículo en Inglés | MEDLINE | ID: mdl-36498985

RESUMEN

Ecto-nucleoside triphosphate diphosphohydrolases (NTPDases) are enzymes located on the surface of the T. cruzi plasma membrane, which hydrolyze a wide range of tri-/-diphosphate nucleosides. In this work, we used previously developed genetically modified strains of Trypanosoma cruzi (T. cruzi), hemi-knockout (KO +/−) and overexpressing (OE) the TcNTPDase-1 gene to evaluate the parasite infectivity profile in a mouse model of acute infection (n = 6 mice per group). Our results showed significantly higher parasitemia and mortality, and lower weight in animals infected with parasites OE TcNTPDase-1, as compared to the infection with the wild type (WT) parasites. On the other hand, animals infected with (KO +/−) parasites showed no mortality during the 30-day trial and mouse weight was more similar to the non-infected (NI) animals. In addition, they had low parasitemia (45.7 times lower) when compared with parasites overexpressing TcNTPDase-1 from the hemi-knockout (OE KO +/−) group. The hearts of animals infected with the OE KO +/− and OE parasites showed significantly larger regions of cardiac inflammation than those infected with the WT parasites (p < 0.001). Only animals infected with KO +/− did not show individual electrocardiographic changes during the period of experimentation. Together, our results expand the knowledge on the role of NTPDases in T. cruzi infectivity, reenforcing the potential of this enzyme as a chemotherapy target to treat Chagas disease (CD).


Asunto(s)
Enfermedad de Chagas , Trypanosoma cruzi , Ratones , Animales , Enfermedad de Chagas/genética , Enfermedad de Chagas/parasitología , Corazón , Modelos Animales de Enfermedad
4.
Molecules ; 27(22)2022 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-36432189

RESUMEN

Chagas disease, caused by Trypanosoma cruzi (T. cruzi), is a serious public health problem. Current treatment is restricted to two drugs, benznidazole and nifurtimox, displaying serious efficacy and safety drawbacks. Nucleoside analogues represent a promising alternative as protozoans do not biosynthesize purines and rely on purine salvage from the hosts. Protozoan transporters often present different substrate specificities from mammalian transporters, justifying the exploration of nucleoside analogues as therapeutic agents. Previous reports identified nucleosides with potent trypanocidal activity; therefore, two 7-derivatized tubercidins (FH11706, FH10714) and a 3'-deoxytubercidin (FH8513) were assayed against T. cruzi. They were highly potent and selective, and the uptake of the tubercidin analogues appeared to be mediated by the nucleoside transporter TcrNT2. At 10 µM, the analogues reduced parasitemia >90% in 2D and 3D cardiac cultures. The washout assays showed that FH10714 sterilized the infected cultures. Given orally, the compounds did not induce noticeable mouse toxicity (50 mg/kg), suppressed the parasitemia of T. cruzi-infected Swiss mice (25 mg/kg, 5 days) and presented DNA amplification below the limit of detection. These findings justify further studies with longer treatment regimens, as well as evaluations in combination with nitro drugs, aiming to identify more effective and safer therapies for Chagas disease.


Asunto(s)
Enfermedad de Chagas , Tripanocidas , Trypanosoma cruzi , Ratones , Animales , Nucleósidos/farmacología , Nucleósidos/uso terapéutico , Tripanocidas/farmacología , Tripanocidas/uso terapéutico , Tripanocidas/química , Parasitemia/tratamiento farmacológico , Enfermedad de Chagas/tratamiento farmacológico , Mamíferos
5.
Exp Parasitol ; 221: 108061, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33383023

RESUMEN

Chagas disease (CD) caused by Trypanosoma cruzi remains a serious public health problem in Latin America. The available treatment is limited to two old drugs, benznidazole (Bz) and nifurtimox, which exhibit limited efficacy and trigger side effects, justifying the search for new therapies. Also, more accurate and sensitive experimental protocols for drug discovery programs are necessary to shrink the translational gaps found among pre-clinical and clinical trials. Presently, cardiac spheroids were used to evaluate host cell cytotoxicity and anti-T.cruzi activity of benznidazole, exploring its effect on the release of inflammatory mediators. Bz presented low toxic profile on 3D matrices (LC50 > 200 µM) and high potency in vitro (EC50 = 0.99 µM) evidenced by qPCR analysis of T.cruzi-infected cardiac spheroids. Flow cytometry appraisal of inflammatory mediators released at the cellular supernatant showed increases in IL - 6 and TNF contents (≈190 and ≈ 25-fold) in parasitized spheroids as compared to uninfected cultures. Bz at 10 µM suppressed parasite load (92%) concomitantly decreasing in IL-6 (36%) and TNF (68%). Our findings corroborate the successful use of 3D cardiac matrices for in vitro identification of novel anti-parasitic agents and potential impact in host cell physiology.


Asunto(s)
Nitroimidazoles/farmacología , Tripanocidas/farmacología , Trypanosoma cruzi/efectos de los fármacos , Animales , Imagenología Tridimensional , Ratones , Microscopía Fluorescente , Conformación Molecular , Esferoides Celulares , Trypanosoma cruzi/crecimiento & desarrollo
6.
Artículo en Inglés | MEDLINE | ID: mdl-32601163

RESUMEN

Pyrazolones are heterocyclic compounds with interesting biological properties. Some derivatives inhibit phosphodiesterases (PDEs) and thereby increase the cellular concentration of cyclic AMP (cAMP), which plays a vital role in the control of metabolism in eukaryotic cells, including the protozoan Trypanosoma cruzi, the etiological agent of Chagas disease (CD), a major neglected tropical disease. In vitro phenotypic screening identified a 4-bromophenyl-dihydropyrazole dimer as an anti-T. cruzi hit and 17 novel pyrazolone analogues with variations on the phenyl ring were investigated in a panel of phenotypic laboratory models. Potent activity against the intracellular forms (Tulahuen and Y strains) was obtained with 50% effective concentration (EC50) values within the 0.17 to 3.3 µM range. Although most were not active against bloodstream trypomastigotes, an altered morphology and loss of infectivity were observed. Pretreatment of the mammalian host cells with pyrazolones did not interfere with infection and proliferation, showing that the drug activity was not the result of changes to host cell metabolism. The pyrazolone NPD-227 increased the intracellular cAMP levels and was able to sterilize T. cruzi-infected cell cultures. Thus, due to its high potency and selectivity in vitro, and its additive interaction with benznidazole (Bz), NPD-227 was next assessed in the acute mouse model. Oral dosing for 5 days of NPD-227 at 10 mg/kg + Bz at 10 mg/kg not only reduced parasitemia (>87%) but also protected against mortality (>83% survival), hence demonstrating superiority to the monotherapy schemes. These data support these pyrazolone molecules as potential novel therapeutic alternatives for Chagas disease.


Asunto(s)
Enfermedad de Chagas , Nitroimidazoles , Pirazolonas , Tripanocidas , Trypanosoma cruzi , Animales , Enfermedad de Chagas/tratamiento farmacológico , Ratones , Nitroimidazoles/uso terapéutico , Inhibidores de Fosfodiesterasa/uso terapéutico , Pirazolonas/farmacología , Pirazolonas/uso terapéutico , Tripanocidas/farmacología , Tripanocidas/uso terapéutico
7.
Parasitology ; 147(11): 1216-1228, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32530391

RESUMEN

In previous studies, we have identified several families of 5-nitroindazole derivatives as promising antichagasic prototypes. Among them, 1-(2-aminoethyl)-2-benzyl-5-nitro-1,2-dihydro-3H-indazol-3-one, (hydrochloride) and 1-(2-acetoxyethyl)-2-benzyl-5-nitro-1,2-dihydro-3H-indazol-3-one (compounds 16 and 24, respectively) have recently shown outstanding activity in vitro over the drug-sensitive Trypanosoma cruzi CL strain (DTU TcVI). Here, we explored the activity of these derivatives against the moderately drug-resistant Y strain (DTU TcII), in vitro and in vivo. The outcomes confirmed their activity over replicative forms, showing IC50 values of 0.49 (16) and 5.75 µm (24) towards epimastigotes, 0.41 (16) and 1.17 µm (24) against intracellular amastigotes. These results, supported by the lack of toxicity on cardiac cells, led to better selectivities than benznidazole (BZ). Otherwise, they were not as active as BZ in vitro against the non-replicative form of the parasite, i.e. bloodstream trypomastigotes. In vivo, acute toxicity assays revealed the absence of toxic events when administered to mice. Moreover, different therapeutic schemes pointed to their capability for decreasing the parasitaemia of T. cruzi Y acute infected mice, reaching up to 60% of reduction at the peak day as monotherapy (16), 79.24 and 91.11% when 16 and 24 were co-administered with BZ. These combined therapies had also a positive impact over the mortality, yielding survivals of 83.33 and 66.67%, respectively, while untreated animals reached a cumulative mortality of 100%. These findings confirm the 5-nitroindazole scaffold as a putative prototype for developing novel drugs potentially applicable to the treatment of Chagas disease and introduce their suitability to act in combination with the reference drug.


Asunto(s)
Indazoles , Trypanosoma cruzi/efectos de los fármacos , Animales , Línea Celular , Enfermedad de Chagas/tratamiento farmacológico , Enfermedad de Chagas/parasitología , Resistencia a Medicamentos , Quimioterapia Combinada , Humanos , Indazoles/farmacología , Indazoles/toxicidad , Ratones , Nitroimidazoles/farmacología , Parasitemia/tratamiento farmacológico , Tripanocidas/farmacología , Tripanocidas/toxicidad
8.
Folia Phoniatr Logop ; 71(1): 7-15, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30481774

RESUMEN

AIMS: To assess the frequency of vocal symptoms and risk factors in individuals with high and low anxiety and to investigate the relationships among vocal symptoms, risk factors, and anxiety levels. PATIENTS AND METHODS: A total of 201 patients of both sexes with a mean age of 42.88 years (SD = 15.78) served as participants. The patients were divided into two groups according to the level of trait anxiety: a low-anxiety group (n = 108) and a high-anxiety group (HAG, n = 93). Data were collected using three self-assessment instruments: the Vocal Screening Protocol, the Voice Symptom Scale (VoiSS), and the State-Trait Anxiety Inventory (STAI). RESULTS: The HAG presented higher scores in all VoiSS domains. There were positive correlations between the total and emotional scores on the VoiSS and the STAI Trait subscale. There were significant associations between 13 vocal risk factors and anxiety levels. CONCLUSION: Individuals with high anxiety present a higher frequency of vocal symptoms related to either vocal limitation, physical aspects, or the emotional impact of dysphonia. The higher the trait anxiety, the greater the total and emotional scores on the VoiSS. Anxiety levels are associated with certain vocal risk factors.


Asunto(s)
Trastornos de Ansiedad/fisiopatología , Ansiedad/fisiopatología , Disfonía/etiología , Calidad de la Voz , Adulto , Ansiedad/psicología , Trastornos de Ansiedad/psicología , Estudios de Casos y Controles , Autoevaluación Diagnóstica , Disfonía/fisiopatología , Escolaridad , Ambiente , Femenino , Hábitos , Humanos , Masculino , Persona de Mediana Edad , Ocupaciones , Factores de Riesgo , Evaluación de Síntomas
9.
Artículo en Inglés | MEDLINE | ID: mdl-29203486

RESUMEN

Five bis-arylimidamides were assayed as anti-Trypanosoma cruzi agents by in vitro, in silico, and in vivo approaches. None were considered to be pan-assay interference compounds. They had a favorable pharmacokinetic landscape and were active against trypomastigotes and intracellular forms, and in combination with benznidazole, they gave no interaction. The most selective agent (28SMB032) tested in vivo led to a 40% reduction in parasitemia (0.1 mg/kg of body weight/5 days intraperitoneally) but without mortality protection. In silico target fishing suggested DNA as the main target, but ultrastructural data did not match.


Asunto(s)
Amidinas/farmacología , Tripanocidas/farmacología , Trypanosoma cruzi/efectos de los fármacos , Animales , Enfermedad de Chagas/tratamiento farmacológico , Masculino , Ratones , Nitroimidazoles/farmacología , Parasitemia/tratamiento farmacológico , Pruebas de Sensibilidad Parasitaria/métodos
10.
Antimicrob Agents Chemother ; 60(2): 1058-66, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26643331

RESUMEN

A novel antifungal drug candidate, the 1-tetrazole-based agent VT-1161 [(R)-2-(2,4-difluorophenyl)-1,1-difluoro-3-(1H-tetrazol-1-yl)-1-{5-[4-(2,2,2-trifluoroethoxy)phenyl]pyridin-2-yl}propan-2-ol], which is currently in two phase 2b antifungal clinical trials, was found to be a tight-binding ligand (apparent dissociation constant [Kd], 24 nM) and a potent inhibitor of cytochrome P450 sterol 14α-demethylase (CYP51) from the protozoan pathogen Trypanosoma cruzi. Moreover, VT-1161 revealed a high level of antiparasitic activity against amastigotes of the Tulahuen strain of T. cruzi in cellular experiments (50% effective concentration, 2.5 nM) and was active in vivo, causing >99.8% suppression of peak parasitemia in a mouse model of infection with the naturally drug-resistant Y strain of the parasite. The data strongly support the potential utility of VT-1161 in the treatment of Chagas disease. The structural characterization of T. cruzi CYP51 in complex with VT-1161 provides insights into the molecular basis for the compound's inhibitory potency and paves the way for the further rational development of this novel, tetrazole-based inhibitory chemotype both for antiprotozoan chemotherapy and for antifungal chemotherapy.


Asunto(s)
Inhibidores de 14 alfa Desmetilasa/farmacología , Piridinas/farmacología , Esterol 14-Desmetilasa/química , Tetrazoles/farmacología , Tripanocidas/farmacología , Trypanosoma cruzi/efectos de los fármacos , Inhibidores de 14 alfa Desmetilasa/química , Animales , Enfermedad de Chagas/tratamiento farmacológico , Cristalografía por Rayos X , Modelos Animales de Enfermedad , Femenino , Hemo/química , Ratones , Modelos Moleculares , Conformación Proteica , Piridinas/química , Esterol 14-Desmetilasa/metabolismo , Tetrazoles/química , Trypanosoma cruzi/enzimología
11.
Genes Chromosomes Cancer ; 54(8): 472-481, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26031834

RESUMEN

Pancreatic ductal adenocarcinoma (PDAC) is driven by the inactivation of the tumor suppressor genes (TSGs), CDKN2A (P16) and SMAD4 (DPC4), commonly by homozygous deletions (HDs). Using a combination of high density single-nucleotide polymorphism (SNP) microarray and whole genome sequencing (WGS), we fine-mapped novel breakpoints surrounding deletions of CDKN2A and SMAD4 and characterized them by their underlying structural variants (SVs). Only one third of CDKN2A and SMAD4 deletions (6 of 18) were simple interstitial deletions, rather, the majority of deletions were caused by complex rearrangements, specifically, a translocation on one side of the TSG in combination with an inversion on the other side. We designate these as "TransFlip" mutations. Characteristics of TransFlip mutations are: (1) a propensity to target the TSGs CDKN2A and SMAD4 (P < 0.005), (2) not present in the germline of the examined samples, (3) non-recurrent breakpoints, (4) relatively small (47 bp to 3.4 kb) inversions, (5) inversions can be either telomeric or centromeric to the TSG, and (6) non-reciprocal, and non-recurrent translocations. TransFlip mutations are novel complex genomic rearrangements with unique breakpoint signatures in pancreatic cancer. We hypothesize that they are a common but poorly understood mechanism of TSG inactivation in human cancer. © 2015 Wiley Periodicals, Inc.

12.
Am J Med Genet A ; 167A(11): 2702-6, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26139517

RESUMEN

Haploinsufficiency of TAB2 was recently implicated as a cause for a variety of congenital heart defects. Reported cases have genomic deletions of 2-10 Mbs including TAB2 at 6q24-25 are almost always de novo and show variable cardiac and extra cardiac phenotype. We report on an inherited, 281 kb deletion in a three generation family. This is the smallest reported deletion involving TAB2 that segregates with congenital heart defects. Three affected individuals in this family present with myxomatous cardiac valves in addition to structural heart defects commonly associated with TAB2 deletions. Findings from this family support a key role of TAB2 haploinsufficiency in congenital heart defects and expand the phenotypic spectrum of TAB2-microdeletion syndrome.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/genética , Deleción Cromosómica , Cardiopatías Congénitas/complicaciones , Cardiopatías Congénitas/genética , Válvulas Cardíacas/anomalías , Tetralogía de Fallot/complicaciones , Tetralogía de Fallot/genética , Adolescente , Adulto , Anciano , Preescolar , Familia , Femenino , Humanos , Recién Nacido , Linaje , Polimorfismo de Nucleótido Simple/genética
13.
Am J Med Genet A ; 167(7): 1644-9, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25823593

RESUMEN

We describe a 0.73 Mb duplication of chromosome 22q11.21 between LCR-B and LCR-D and a missense mutation in a conserved C2H2 zinc finger domain of SALL4 in a cognitively normal patient with multiple skeletal anomalies including radioulnar synostosis, thumb aplasia, butterfly vertebrae, rib abnormalities, and hypoplasia of the humeral and femoral epiphyses. 22q11.21 is a common site for microdeletions and their reciprocal microduplications as a result of non-allelic homologous recombination between its multiple low copy repeat regions (LCR). DiGeorge /Velocardiofacial syndrome (DG/VCFS) is classically caused by a 3 Mb deletion between LCR-A and LCR-D or a 1.5 Mb deletion between LCR-A and LCR-B. The reciprocal syndrome to DG/VCFS is the recently described 22q11.2 microduplication, which usually presents with the typical 3 Mb or 1.5 Mb duplication. Numerous atypical deletions and duplications have been reported between other LCRs. Typically, SALL4-related Duane-radial ray syndrome is caused by deletions or nonsense mutations; the only missense SALL4 mutation described prior was thought to result in gain of function and produced cranial midline defects. The skeletal anomalies presented in this report have not been previously described in association with 22q11.2 microduplication nor SALL4 mutations.


Asunto(s)
Anomalías Múltiples/genética , Trastornos de los Cromosomas/genética , Duplicación Cromosómica/genética , Cromosomas Humanos Par 22/genética , Deformidades de la Mano/genética , Radio (Anatomía)/anomalías , Sinostosis/genética , Pulgar/anomalías , Factores de Transcripción/genética , Cúbito/anomalías , Anomalías Múltiples/patología , Secuencia de Bases , Trastornos de los Cromosomas/patología , Deformidades de la Mano/patología , Humanos , Datos de Secuencia Molecular , Mutación Missense/genética , Polimorfismo de Nucleótido Simple , Radio (Anatomía)/patología , Duplicaciones Segmentarias en el Genoma/genética , Análisis de Secuencia de ADN , Sinostosis/patología , Pulgar/patología , Cúbito/patología
14.
Am J Med Genet A ; 167A(5): 1147-51, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25851414

RESUMEN

Recently, mutations in FARS2, which encodes for mitochondrial phenylalanyl-tRNA synthetase, have been implicated in autosomal recessive combined oxidative phosphorylation deficiency 14. Associated clinical features in three previously reported patients with confirmed FARS2 mutations include infantile onset epilepsy, and a fatal Alpers-like encephalopathy. Herein, we report on two siblings with global developmental delay, dysarthria and tremor and compound heterozygous FARS2 abnormalities. They have a heterozygous missense mutation, c.1255C>T which predicts p.Arg419Cys in exon 7 of FARS2, inherited from their father and uncovered on exome sequencing, and an interstitial deletion of chromosome 6p25.1 inherited from their mother and uncovered on SNP array. This interstitial deletion includes all of exon 6 and parts of introns 5 and 6 of FARS2. Biochemical studies were also consistent with a mitochondrial disorder. While these siblings had considerable developmental difficulties, they are making consistent developmental progress and appear to be considerably less severely affected than the other patients reported in the literature with FARS2 associated mitochondrial disease. Thus, this study expands the phenotypic spectrum of FARS2 related disease and emphasizes intragenic deletion in the list of causative mutations.


Asunto(s)
Lóbulo Frontal/fisiopatología , Mitocondrias/genética , Enfermedades Mitocondriales/genética , Fenilalanina-ARNt Ligasa/genética , Adolescente , Niño , Preescolar , Exoma/genética , Exones/genética , Femenino , Lóbulo Frontal/diagnóstico por imagen , Humanos , Imagen por Resonancia Magnética , Masculino , Mitocondrias/enzimología , Mitocondrias/patología , Enfermedades Mitocondriales/diagnóstico por imagen , Enfermedades Mitocondriales/fisiopatología , Mutación Missense , Linaje , Radiografía , Hermanos , Sustancia Blanca/diagnóstico por imagen , Sustancia Blanca/fisiopatología
15.
Mod Pathol ; 27(4): 562-8, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24051698

RESUMEN

The biological behavior of teratomas is highly variable, and morphologic features alone are insufficient to predict their clinical course. Prognostic factors that influence behavior include the following: patient sex, age, anatomic site, coincident neoplasm, and cytogenetic abnormalities. Gonadal teratomas have been well-characterized; postpubertal testicular teratomas are commonly associated with isochromosome 12p (i12p) and considered to nearly always carry a potential for malignant behavior, whereas ovarian and prepubertal testicular teratomas are i12p negative and predominantly benign in behavior. For extragonadal sites, such as sacrum and coccyx, clinical characteristics and i12p status are yet to be adequately characterized. As part of this study, we identified 19 sacrococcygeal teratomas in our surgical pathology archives from 1990 to 2012. Clinical records and slides were reviewed to confirm the original diagnosis. Gains in chromosome 12p, including i12p status were assessed in representative paraffin sections by fluorescence in situ hybridization. Our cases included 16 mature sacrococcygeal teratomas (11 prepubertal and 5 postpubertal) and three immature saccrococygeal teratomas (all prepubertal). Among mature teratomas, the average tumor size was larger in adults compared with prepubertal patients. A higher number of adult cases were recurrences (80% vs 21%), but only pediatric recurrences were managed with postoperative chemotherapy. All examined tumors were negative for i12p. 100% survival was documented in our cohort with a median follow-up of 6 years. We present a large series of sacrococcygeal teratomas and the first series to examine postpubertal adults at this anatomic site. All tumors lacked chromosome 12p gains, including i12p. Both pre- and postpubertal sacrococcygeal teratomas had a favorable outcome regardless of age or sex.


Asunto(s)
Biomarcadores de Tumor/genética , Cromosomas Humanos Par 12 , Isocromosomas , Sacro , Neoplasias de la Columna Vertebral/genética , Teratoma/genética , Adulto , Preescolar , Femenino , Predisposición Genética a la Enfermedad , Humanos , Hibridación Fluorescente in Situ , Lactante , Recién Nacido , Masculino , Persona de Mediana Edad , Fenotipo , Neoplasias de la Columna Vertebral/patología , Neoplasias de la Columna Vertebral/terapia , Análisis de Supervivencia , Teratoma/patología , Teratoma/terapia , Resultado del Tratamiento
16.
Genet Med ; 16(9): 657-64, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24625444

RESUMEN

PURPOSE: Chromosomal microarray has been widely adopted as the first-tier clinical test for individuals with multiple congenital anomalies, developmental delay, intellectual disability, and autism spectrum disorders. Although chromosomal microarray has been extensively shown to provide a higher diagnostic yield than conventional cytogenetic methods, some health insurers refuse to provide coverage for this test, claiming that it is experimental and does not affect patients' clinical management. METHODS: We retrospectively reviewed the electronic medical records of all patients who had abnormal chromosomal microarray findings reported by our laboratory over a 3-year period and quantified the management recommendations made in response to these results. RESULTS: Abnormal chromosomal microarray findings were reported for 12.7% of patients (227/1,780). For patients with clinical follow-up notes available, these results had management implications for 54.5% of patients in the entire abnormal cohort (102/187) and for 42.1% of patients referred for isolated neurodevelopmental disorders (16/38). Recommendations included pharmacological treatment, cancer-related screening or exclusion of screening, contraindications, and referrals for further evaluation. CONCLUSION: These results empirically demonstrate the clinical utility of chromosomal microarray by providing evidence that management was directly affected for the majority of patients in our cohort with abnormal chromosomal microarray findings.


Asunto(s)
Cromosomas Humanos , Manejo de la Enfermedad , Pruebas Genéticas , Análisis de Secuencia por Matrices de Oligonucleótidos , Niño , Preescolar , Detección Precoz del Cáncer , Femenino , Estudios de Seguimiento , Pruebas Genéticas/métodos , Humanos , Lactante , Masculino , Polimorfismo de Nucleótido Simple , Derivación y Consulta , Estudios Retrospectivos
17.
Parasitology ; 141(3): 367-73, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24553079

RESUMEN

Chagas disease (CD) is caused by the intracellular protozoan parasite Trypanosoma cruzi and affects more than 10 million people in poor areas of Latin America. There is an urgent need for alternative drugs with better safety, broader efficacy, lower costs and shorter time of administration. Thus the biological activity of viniconazole, a chloroaryl-substituted imidazole was investigated using in vitro and in vivo screening models of T. cruzi infection. Ultrastructural findings demonstrated that the most frequent cellular damage was associated with plasma membrane (blebs and shedding events), Golgi (swelling aspects) and the appearance of large numbers of vacuoles suggesting an autophagic process. Our data demonstrated that although this compound is effective against bloodstream and intracellular forms (16 and 24 µ m, respectively) in vitro, it does not present in vivo efficacy. Due to the urgent need for novel agents against T. cruzi, the screening of natural and synthetic products must be further supported with the aim of finding more selective and affordable drugs for CD.


Asunto(s)
Enfermedad de Chagas/tratamiento farmacológico , Imidazoles/farmacología , Tripanocidas/farmacología , Trypanosoma cruzi/efectos de los fármacos , Animales , Enfermedad de Chagas/parasitología , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Humanos , Imidazoles/química , Imidazoles/uso terapéutico , Masculino , Ratones , Parasitemia/tratamiento farmacológico , Parasitemia/parasitología , Pruebas de Sensibilidad Parasitaria , Cultivo Primario de Células , Tripanocidas/química , Tripanocidas/uso terapéutico , Trypanosoma cruzi/ultraestructura
18.
Dev Med Child Neurol ; 56(11): 1124-8, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24684524

RESUMEN

Homozygous deletions of chromosome 20p12.3, disrupting the promoter region and first three coding exons of the phospholipase C ß1 gene (PLCB1), have previously been described in two reports of early infantile epileptic encephalopathy (EIEE). Both children were born to consanguineous parents, one presented with infantile spasms, the other with migrating partial seizures of infancy. We describe an infant presenting with severe intractable epilepsy (without a specific EIEE electroclinical syndrome diagnosis) and neurodevelopmental delay associated with compound heterozygous mutations in PLCB1. A case note review and molecular genetic investigations were performed for a child, approximately 10 months of age, admitted to Johns Hopkins University Hospital for developmental delay and new-onset seizures. The patient presented at 6 months of age with developmental delay, followed by the onset of intractable, focal, and generalized seizures associated with developmental regression from 10 months of age. Presently, at 2 years of age, the child has severe motor and cognitive delays. Diagnostic microarray revealed a heterozygous 476kb deletion of 20p12.3 (encompassing PLCB1), which was also detected in the mother. The genomic breakpoints for the heterozygous deletion were determined. In order to investigate the presence of a second PLCB1 mutation, direct Sanger sequencing of the coding region and flanking intronic regions was undertaken, revealing a novel heterozygous intron 1 splice site variant (c.99+1G>A) in both the index individual and the father. Advances in molecular genetic testing have greatly improved diagnostic rates in EIEE, and this report further confirms the important role of microarray investigation in this group of disorders. PLCB1-EIEE is now reported in a number of different EIEE phenotypes and our report provides further evidence for phenotypic pleiotropy encountered in early infantile epilepsy syndromes.


Asunto(s)
Epilepsia Tónico-Clónica/genética , Mutación , Fosfolipasa C beta/genética , Discapacidades del Desarrollo , Electroencefalografía , Femenino , Genotipo , Humanos , Lactante , Fenotipo , Índice de Severidad de la Enfermedad
19.
Biol Blood Marrow Transplant ; 19(8): 1254-9, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23769818

RESUMEN

Potential bone marrow donors are screened to ensure the safety of both the donor and recipient. At our institution, potential donors with abnormal peripheral blood cell counts, a personal history of malignancy, or age >60 years are evaluated to ensure that they are viable candidates for donation. Evaluation of the marrow includes morphologic, flow cytometric, and cytogenetic studies. A total of 122 potential donors were screened between the years of 2001 and 2011, encompassing approximately 10% of all donors. Of the screened potential donors, the mean age was 59 years and there were 59 men and 63 women. The donors were screened because of age >60 years (n = 33), anemia (n = 22), cytopenias other than anemia (n = 27), elevated peripheral blood counts without a concurrent cytopenia (n = 20), elevated peripheral blood counts with a concurrent cytopenia (n = 10), history of malignancy (n = 4), abnormal peripheral blood differential (n = 3), prior graft failure (n = 1), history of treatment with chemotherapy (n = 1), and body habitus (n = 1). Marrow abnormalities were detected in 9% (11 of 122) of donors. These donors were screened because of anemia (5 of 22, 23%), age >60 years (2 of 33, 6%), history of malignancy (2 of 4, 50%), elevated peripheral blood counts (1 of 20, 5%), and body habitus (1 of 1, 100%). Abnormalities included plasma cell dyscrasia (n = 3), abnormal marrow cellularity (n = 3), clonal cytogenetic abnormalities (n = 2), low-grade myelodysplastic syndrome (1), a mutated JAK2 V617F allele (n = 1), and monoclonal B cell lymphocytosis (n = 1). Our experience indicates that extended screening of potential donors identifies a significant number of donors with previously undiagnosed marrow abnormalities.


Asunto(s)
Células de la Médula Ósea/patología , Trasplante de Médula Ósea/métodos , Médula Ósea/anomalías , Donadores Vivos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Médula Ósea/patología , Trasplante de Médula Ósea/efectos adversos , Citogenética , Femenino , Citometría de Flujo , Humanos , Masculino , Persona de Mediana Edad , Donantes de Tejidos , Adulto Joven
20.
Antimicrob Agents Chemother ; 57(11): 5307-14, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23939901

RESUMEN

In vitro and in vivo activities against Trypanosoma cruzi were evaluated for two sesquiterpene lactones: psilostachyin A and cynaropicrin. Cynaropicrin had previously been shown to potently inhibit African trypanosomes in vivo, and psilostachyin A had been reported to show in vivo effects against T. cruzi, albeit in another test design. In vitro data showed that cynaropicrin was more effective than psilostachyin A. Ultrastructural alterations induced by cynaropicrin included shedding events, detachment of large portions of the plasma membrane, and vesicular bodies and large vacuoles containing membranous structures, suggestive of parasite autophagy. Acute toxicity studies showed that one of two mice died at a cynaropicrin dose of 400 mg/kg of body weight given intraperitoneally (i.p.). Although no major plasma biochemical alterations could be detected, histopathology demonstrated that the liver was the most affected organ in cynaropicrin-treated animals. Although cynaropicrin was as effective as benznidazole against trypomastigotes in vitro, the treatment (once or twice a day) of T. cruzi-infected mice (up to 50 mg/kg/day cynaropicrin) did not suppress parasitemia or protect against mortality induced by the Y and Colombiana strains. Psilostachyin A (0.5 to 50 mg/kg/day given once a day) was not effective in the acute model of T. cruzi infection (Y strain), reaching 100% animal mortality. Our data demonstrate that although it is very promising against African trypanosomes, cynaropicrin does not show efficacy compared to benznidazole in acute mouse models of T. cruzi infection.


Asunto(s)
Enfermedad de Chagas/tratamiento farmacológico , Hígado/efectos de los fármacos , Nitroimidazoles/farmacología , Tripanocidas/farmacología , Trypanosoma cruzi/efectos de los fármacos , Animales , Autofagia/efectos de los fármacos , Membrana Celular/efectos de los fármacos , Membrana Celular/ultraestructura , Enfermedad de Chagas/mortalidad , Enfermedad de Chagas/parasitología , Lactonas/farmacología , Hígado/parasitología , Hígado/patología , Masculino , Ratones , Microscopía Electrónica de Transmisión , Pruebas de Sensibilidad Parasitaria , Sesquiterpenos/farmacología , Análisis de Supervivencia , Insuficiencia del Tratamiento , Trypanosoma cruzi/crecimiento & desarrollo , Trypanosoma cruzi/ultraestructura , Vacuolas/efectos de los fármacos , Vacuolas/ultraestructura
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