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1.
J Eur Acad Dermatol Venereol ; 35(1): 211-215, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32216136

RESUMEN

BACKGROUND: Granuloma annulare (GA) and the related annular elastolytic giant cell granuloma (AEGCG) and interstitial granulomatous dermatitis (IGD) are idiopathic histiocytic inflammatory disorders, which are frequently recalcitrant to treatment. OBJECTIVES: Evaluate the efficacy of sulphasalazine in treating GA, AEGCG and IGD. METHODS: Sixteen patients were identified with granulomatous disease who were treated with sulphasalazine between September 2015 and September 2019. Outcomes were based on patients' and providers' subjective evaluations. RESULTS: Sixteen patients were included in the study (ages 56-89, four male and twelve female). Previous treatments were attempted in fifteen patients. Clinical improvement was seen in fourteen patients (87.5%). Initial improvement was noted within a mean (SD) of 66.4 (35.1) days after starting therapy, with increasing benefits over time. Ten patients (62.5%) reported complete or near-complete clearance, three patients (18.8%) reported significant improvement, and one (6.3%) reported partial improvement. Twelve patients elected to stop or reduce therapy, resulting in relapse or worsening in five patients. CONCLUSIONS: Sulphasalazine may be considered as treatment for GA and GA-related conditions.


Asunto(s)
Dermatitis , Granuloma Anular , Granuloma de Células Gigantes , Anciano , Anciano de 80 o más Años , Dermatitis/tratamiento farmacológico , Femenino , Granuloma , Granuloma Anular/tratamiento farmacológico , Humanos , Masculino , Persona de Mediana Edad , Sulfasalazina/uso terapéutico
2.
Med Vet Entomol ; 34(3): 264-278, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32031286

RESUMEN

The aim of this work was to test the efficacy of winter-spring control strategies against Rhipicephalus (Boophilus) microplus (Canestrini, 1888) (Ixodida: Ixodidae) in an area highly favourable for its development in Argentina. Control schemes using three or four annual applications of synthetic acaricides were evaluated. Furthermore, the dynamics of the non-parasitic phases of R. microplus were analysed to provide a framework for the application of pasture spelling as a tool for tick control. The treatment schemes provided appropriate levels of efficacy against R. microplus and also prevented the occurrence of the major peak in abundance of this tick in autumn. A significant overall effect against R. microplus can be achieved when the control strategies tested in this study are applied within the area most ecologically favourable for this tick in Argentina. Analysis of the dynamics of the non-parasitic phase of R. microplus indicates that the spelling period required to achieve a significant reduction of larvae in pastures fluctuates between 12 and 17 weeks if spelling is initiated in spring or early summer, but between 20 and 28 weeks if spelling is started in late summer, autumn or winter.


Asunto(s)
Acaricidas , Rhipicephalus , Control de Ácaros y Garrapatas/métodos , Animales , Argentina , Femenino , Larva
3.
Med Vet Entomol ; 33(2): 312-316, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-30671993

RESUMEN

This work was performed to test the efficacy of winter-spring control strategies against Rhipicephalus (Boophilus) microplus (Ixodida: Ixodidae) infestations on cattle in the area ecologically most favourable for the development of this tick in Argentina. Two control schemes using three and four annual applications of acaricides, respectively, were evaluated. Animals in Group 1 were treated with ivermectin 3.15% on day 0, fluazuron on day 34, and fipronil on day 85. Animals in Group 2 were treated with ivermectin 3.15% on day 0, fluazuron on day 34, flumethrin on day 85, and fipronil on day 114. Animals in Group 3 represented the control group. Both treatment schemes provided appropriate levels of efficacy against R. microplus and also prevented the occurrence of the major peak in the frequency of this tick in autumn. The two treatment schemes were similar in terms of efficacy and thus the addition of a fourth treatment does not seem to confer any further advantage. The results of this work indicate that these strategic control methods provide appropriate levels of control against R. microplus.


Asunto(s)
Acaricidas/farmacología , Enfermedades de los Bovinos/prevención & control , Erradicación de la Enfermedad/métodos , Rhipicephalus/efectos de los fármacos , Infestaciones por Garrapatas/veterinaria , Animales , Argentina , Bovinos , Enfermedades de los Bovinos/parasitología , Ecosistema , Femenino , Rhipicephalus/fisiología , Estaciones del Año , Infestaciones por Garrapatas/parasitología , Infestaciones por Garrapatas/prevención & control
4.
J Eur Acad Dermatol Venereol ; 32(9): 1450-1455, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29178552

RESUMEN

BACKGROUND: The benign and malignant patterns of acral melanocytic naevi (AMN) and acral melanomas (AM) have been defined in a series of retrospective studies. A three-step algorithm was developed to determine when to biopsy acral melanocytic lesions. This algorithm has only been applied to a Japanese population. OBJECTIVES: Our study aimed to review the current management strategy of acral melanocytic lesions and to investigate the utility of the three-step algorithm in a predominately Caucasian cohort. METHODS: A retrospective search of the pathology and image databases at Mayo Clinic was performed between the years 2006 and 2016. Only cases located on a volar surface with dermoscopic images were included. Two dermatologists reviewed all dermoscopic images and assigned a global dermoscopic pattern. Clinical and follow-up data were gathered by chart review. All lesions with known diameter and pathological diagnosis were used for the three-step algorithm. RESULTS: Regular fibrillar and ridge patterns were more likely to be biopsied (P = 0.01). The majority of AMN (58.1%) and AM (60%) biopsied were due to physician-deemed concerning dermoscopic patterns. 39.2% of these cases were parallel furrow, lattice-like or regular fibrillar. When patients were asked to follow-up within a 3- to 6-month period, only 16.7% of the patients returned within that interval. The three-step algorithm would have correctly identified four of five AM for biopsy, missing a 6 mm, multicomponent, invasive melanoma. CONCLUSION: We found one major educational gap in the recognition of low-risk lesions with high rates of biopsy of the fibrillary pattern. Recognizing low-risk dermoscopic patterns could reduce the rate of biopsy of AMN by 23.3%. We identified two major practice gaps, poor patient compliance with follow-up and the potential insensitivity of the three-step algorithm to small multicomponent acral melanocytic lesions.


Asunto(s)
Dermoscopía , Enfermedades del Pie/diagnóstico por imagen , Melanoma/diagnóstico por imagen , Neoplasias Primarias Secundarias/diagnóstico por imagen , Nevo Pigmentado/diagnóstico por imagen , Neoplasias Cutáneas/diagnóstico por imagen , Adulto , Anciano , Algoritmos , Biopsia , Dermoscopía/educación , Femenino , Enfermedades del Pie/patología , Mano , Humanos , Masculino , Melanoma/patología , Persona de Mediana Edad , Neoplasias Primarias Secundarias/patología , Nevo Pigmentado/patología , Estudios Retrospectivos , Piel/patología , Neoplasias Cutáneas/patología
5.
Allergy ; 72(2): 266-273, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27261450

RESUMEN

BACKGROUND: IgG to galactose-α-1,3-galactose (α-gal) are highly abundant natural antibodies (Ab) in humans. α-Gal-specific IgE Ab cause a special form of meat allergy characterized by severe systemic reactions 3-7 h after consumption of red meat. We investigated 20 patients who experienced such reactions and characterized their α-gal-specific IgE and IgG responses in more detail. METHODS: α-Gal-specific IgE was determined by ImmunoCAP. IgE reactivity to meat extract and bovine gamma globulin (BGG) was assessed by immunoblotting and ELISA, respectively. In some experiments, sera were pre-incubated with α-gal or protein G to deplete IgG Ab. α-Gal-specific IgG1-4 Ab in individuals with and without meat allergy were assessed by ELISA. RESULTS: In immunoblots, BGG was the most frequently recognized meat protein. Binding of IgE and IgG to BGG was confirmed by ELISA and completely abolished after pre-incubation with α-gal. Neither the depletion of autologous α-gal-specific IgG Ab nor the addition of α-gal-specific IgG Ab from nonallergic individuals changed the IgE recognition of BGG of meat-allergic patients. Meat-allergic patients showed significantly higher α-gal-specific IgG1 and IgG3 Ab than nonallergic individuals, whereas the latter showed significantly higher levels of α-gal-specific IgG4 Ab. CONCLUSION: Patients with delayed meat allergy display IgE and IgG Ab that selectively recognize the α-gal epitope on BGG. Their enhanced α-gal-specific IgE levels are accompanied by high levels of α-gal-specific IgG1 devoid of IgE-blocking activity. This subclass distribution is atypical for food allergies and distinct from natural α-gal IgG responses in nonallergic individuals.


Asunto(s)
Alérgenos/inmunología , Anticuerpos/inmunología , Hipersensibilidad a los Alimentos/inmunología , Galactosa/inmunología , Hipersensibilidad Tardía/inmunología , Carne Roja/efectos adversos , Adulto , Anciano , Anciano de 80 o más Años , Especificidad de Anticuerpos/inmunología , Femenino , Humanos , Inmunoglobulina E/inmunología , Inmunoglobulina G/inmunología , Masculino , Persona de Mediana Edad
6.
Med Vet Entomol ; 31(1): 6-14, 2017 03.
Artículo en Inglés | MEDLINE | ID: mdl-27747901

RESUMEN

The population dynamics of Rhipicephalus microplus (Ixodida: Ixodidae) in northwest Argentina was analysed to support the design of strategic methods for its control. Both parasitic and non-parasitic phases were studied. The seasonal activity of R. microplus in its parasitic phase was characterized by three peaks in abundance: the first in mid-late spring; the second in summer, and the third in autumn. The non-parasitic phase of R. microplus was characterized by a long total non-parasitic period observed after exposures of females from mid-summer to early autumn, a short total non-parasitic period observed after exposures of females from late winter to late spring, a short period of larval longevity in early and mid-summer, and no hatch of the eggs produced by females exposed in mid- and late autumn and winter. Treatments of cattle administered during the period from late winter to late spring will act on small cohorts of R. microplus, preventing the emergence of larger generations in summer and autumn. A 17-week spelling period starting in late spring and early summer will be necessary to achieve optimal control of R. microplus free-living larvae. If spelling begins in mid- or late summer or in autumn, the required period will be 26-27 weeks.


Asunto(s)
Enfermedades de los Bovinos/prevención & control , Rhipicephalus/fisiología , Control de Ácaros y Garrapatas/métodos , Infestaciones por Garrapatas/veterinaria , Animales , Argentina , Bovinos , Enfermedades de los Bovinos/parasitología , Larva/crecimiento & desarrollo , Larva/fisiología , Dinámica Poblacional , Rhipicephalus/crecimiento & desarrollo , Estaciones del Año , Infestaciones por Garrapatas/parasitología , Infestaciones por Garrapatas/prevención & control
7.
Br J Dermatol ; 174(4): 881-884, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26574343

RESUMEN

Coccidioides species are soil-dwelling fungi endemic to the Southwest U.S.A., especially Arizona and California and Northern Mexico. The cutaneous findings of coccidioidomycosis have a wide range of pathology, which includes organism-specific and reactive processes. Interstitial granulomatous dermatitis (IGD), a granuloma annulare-like reaction, has been described, in a limited form, in association with acute pulmonary coccidioidomycosis. We present a case of chronic, widespread IGD spanning over 9 years in association with an active coccidioidomycosis infection. Similar clinical and histopathological features have been described in association with drug reactions, connective tissue diseases, systemic vasculitis, lymphomas, other infectious diseases and inflammatory bowel disease. Our patient's dramatic presentation and chronic course expands upon the clinical spectrum of IGD occurring in association with pulmonary coccidioidomycosis. While IGD in association with coccidioidomycosis is rare, both dermatologists and general practitioners see IGD reactions, and our case highlights the importance of identifying the underlying driver.

9.
Med Vet Entomol ; 29(3): 297-304, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25736471

RESUMEN

The ecology of Amblyomma tonelliae (Ixodida: Ixodidae), including its seasonal distribution and the development periods of each stage, was investigated during a study carried out over two consecutive years in northwestern Argentina. In addition, the genetic variation of this tick was studied through analyses of 16S rDNA sequences. Amblyomma tonelliae has a 1-year lifecycle characterized by a long pre-moult period in larvae with no development of morphogenetic diapause. Larvae peak in abundance during late autumn and early winter; nymphs peak in abundance in spring, and adults do so from late spring to early summer. Amblyomma tonelliae shows a marked ecological preference for the driest areas of the Chaco ecoregion. In analyses of 16S rDNA sequences in genes from different populations of A. tonelliae, values for nucleotide diversity and the average number of nucleotide differences showed genetic diversity within this species to be low. No significant differences were found in comparisons among populations.


Asunto(s)
Ecosistema , Variación Genética , Ixodidae/fisiología , Animales , Argentina , Femenino , Ixodidae/genética , Ixodidae/crecimiento & desarrollo , Larva/genética , Larva/crecimiento & desarrollo , Larva/fisiología , Masculino , Datos de Secuencia Molecular , Ninfa/genética , Ninfa/crecimiento & desarrollo , Ninfa/fisiología , Filogenia , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN
11.
Exp Parasitol ; 141: 98-105, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24681200

RESUMEN

The population structure of original Babesia bigemina isolates and reference strains with a defined phenotypic profile was assessed using 18S rRNA and rap-1c genes. Two reference strains, BbiS2P-c (virulent) and BbiS1A-c (low virulence), were biologically cloned in vitro. The virulence profile of the strains and clones was assessed in vivo. One fully virulent and one low-virulence clone were mixed in identical proportions to evaluate their growth efficiency in vitro. Each clone was differentiated by two microsatellites and the gene gp45. The 18S rRNA and rap-1c genes sequences from B. bigemina biological clones and their parental strains, multiplied exclusively in vivo or in vitro, were compared with strain JG-29. The virulence of clones derived from the BbiS2P-c strain was variable. Virulent clone Bbi9P1 grew more efficiently in vitro than did the low-virulence clone Bbi2A1. The haplotypes generated by the nucleotide polymorphism, localized in the V4 region of the 18S rRNA, allowed the identification of three genotypes. The rap-1c haplotypes allowed defining four genotypes. Parental and original strains were defined by multiple haplotypes identified in both genes. The rap-1c gene, analyzed by high-resolution melting (HRM), allowed discrimination between two genotypes according to their phenotype, and both were different from JG-29. B. bigemina biological clones made it possible to define the population structure of isolates and strains. The polymorphic regions of the 18S rRNA and rap-1c genes allowed the identification of different subpopulations within original B. bigemina isolates by the definition of several haplotypes and the differentiation of fully virulent from low virulence clones.


Asunto(s)
Babesia/patogenicidad , Babesiosis/veterinaria , Enfermedades de los Bovinos/parasitología , Proteínas Protozoarias/genética , ARN Ribosómico 18S/genética , Animales , Argentina/epidemiología , Babesia/clasificación , Babesia/genética , Babesiosis/epidemiología , Babesiosis/parasitología , Secuencia de Bases , Bovinos , Enfermedades de los Bovinos/epidemiología , Clonación Molecular , ADN Protozoario/química , ADN Protozoario/aislamiento & purificación , Eritrocitos/parasitología , Genotipo , Técnicas de Genotipaje , Haplotipos , Masculino , Datos de Secuencia Molecular , ARN Ribosómico 18S/química , Reacción en Cadena en Tiempo Real de la Polimerasa/normas , Alineación de Secuencia , Virulencia
13.
Resuscitation ; 151: 26-32, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32251701

RESUMEN

AIM: Despite an increased rate of return of spontaneous circulation (ROSC) in out-of-hospital cardiac arrest (OHCA) patients, almost half of patients do not survive up to hospital discharge. Understanding pathophysiological mechanisms of post-cardiac arrest syndrome is essential for developing novel therapeutic strategies. During systemic inflammatory responses and concomitant cell death, double-stranded (ds) DNA is released into circulation, exerting pro-inflammatory effects. Deoxyribonuclease (DNase) degrades dsDNA. The role of DNase activity in OHCA survivors and impact on clinical outcome has not been analyzed yet. METHODS: In a prospective, single-center study, dsDNA and DNase activity were determined at hospital admission (acute phase) and 24 h (subacute phase) after ROSC. The ratio between dsDNA levels and DNase activity was calculated to determine the extent of dsDNA release in relation to the patients' capacity of degradation. Thirty-day mortality was defined as study end point. RESULTS: We enrolled 64 OHCA survivors, of whom 26.6% (n = 17) died within 30 days. A peak of circulating dsDNA was observed at admission which decreased within 24 h. DNase activity did not differ between acute and subacute phase, while dsDNA load per DNase activity significantly decreased. The ratio between dsDNA levels and DNase activity in the subacute phase was the strongest predictor of 30-day mortality with an adjusted HR per 1 SD of 3.59 (95% CI, 1.80-7.18, p < 0.001). CONCLUSION: Disproportionally increased dsDNA levels uncompensated by DNase activity are a strong predictor of mortality in OHCA survivors. This pilot study points to a potentially protective effect of DNase activity in patients undergoing cardiac arrest.


Asunto(s)
Reanimación Cardiopulmonar , Paro Cardíaco Extrahospitalario , ADN , Desoxirribonucleasas , Humanos , Proyectos Piloto , Estudios Prospectivos
14.
Med Vet Entomol ; 23(1): 1-5, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19067794

RESUMEN

One ear of each of five cows on a property close to Dean Funes, province of Córdoba, Argentina, was inspected monthly from December 2004 to November 2006 to determine the presence of Otobius megnini (Dugès) and to ascertain its seasonality. Ticks were collected to study the biological parameters of larvae, nymphs and adult ticks. Groups of nymphs were also maintained at three different photoperiods at 25 degrees C. The abundance of immature stages was greatest during January-April and August-October in the first and second years of the study, respectively. No larvae successfully moulted. Nymphs weighing < 17 mg also failed to moult, but 89% of heavier nymphs moulted into adults. Nymphs moulting to males weighed less (49.5 +/- 16.09 mg) than nymphs moulting to females (98.1 +/- 34.08 mg). The pre-moult period was similar for nymphs moulting to either sex and significantly longer (P < 0.01) for female nymphs maintained at 25 degrees C compared with nymphs kept at 27 degrees C. No effect of photoperiod on the pre-moult periods of nymphs was detected. Female ticks produced a mean of 7.0 +/- 1.94 egg batches after a preoviposition period of 16.4 +/- 8.41 days for the first batch. The mean oviposition period was 61 +/- 20.8 days and the duration of oviposition for each batch varied from 1 to 6 days. The mean number of eggs per batch was 93.1 +/- 87.53. The minimum incubation period for the first egg batch was 13.6 +/- 2.77 days. The total number of eggs laid by each female was 651.6 +/- 288.90. Parthenogenesis was not observed. The reproductive efficiency index (REI) (number of eggs laid/weight of female in mg) was 5.5 +/- 1.26. Pearson's correlations showed a significant direct relationship between the weight of the female and number of eggs laid (P < 0.01) and REI (P < 0.05). Several of the biological values presented above for the tick population from the Neotropical zoogeographic region showed marked differences to equivalent values for O. megnini populations from the U.S.A. (Nearctic) and India (Oriental). Nevertheless, the only two sequences of 16S rDNA deposited in GenBank from ticks originating in Argentina and allegedly in the U.S.A. indicate that they are conspecific (99.8% agreement). We tentatively consider the biological differences among populations of this tick species to represent adaptations for survival at different conditions.


Asunto(s)
Enfermedades de los Bovinos/parasitología , Ixodidae/fisiología , Infestaciones por Garrapatas/veterinaria , Animales , Bovinos , Femenino , Larva/fisiología , Masculino , Muda , Ninfa/fisiología , Infestaciones por Garrapatas/parasitología , Factores de Tiempo
15.
Thorac Cardiovasc Surg ; 57(4): 191-5, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19670109

RESUMEN

BACKGROUND: We have previously shown that the alpha-Gal (Galalpha1.3-Galbeta1-4GlcNAc-R) epitope is a relevant xenoantigen present on bioprostheses utilized in cardiac surgery and elicits an alpha-Gal specific IgM immune response. We sought to investigate whether that immune response continues after valve implantation. MATERIALS AND METHODS: We collected plasma samples from patients who underwent bioprosthesis implantation (n = 19) or mechanical valve replacement (n = 8), respectively, prior to, at 10 days and at 3 months after cardiac surgery. ELISA was utilized to quantify alpha-Gal specific IgG and IgG subclasses. 3 bioprosthetic tissue samples were obtained from patients who had to undergo re-operation within 1 week (n = 1) or at 12-15 months (n = 2) after the initial operation. We utilized confocal laser scanning microscopy (CLSM) to detect the presence of alpha-Gal epitopes (IB4) and cell nuclei (DAPI). RESULTS: alpha-Gal specific IgG was significantly increased 3 months after implantation of bioprostheses compared to preoperative values (p < 0.001) and was significantly higher than alpha-Gal specific IgG levels of the control group (p < 0.05). IgG3 was the major subclass directed against alpha-Gal (p < 0.05, pre- vs. postoperative values). In CLSM analysis we demonstrated that bioprostheses explanted 1 week after implantation contained IB4/DAPI positive cells within the collagen matrix. In contrast, in patients who underwent reoperation after 12 months, porcine tissue showed a complete lack of IB4/DAPI. CONCLUSION: Our results indicate that the implantation of bioprostheses elicits a specific humoral immune response against alpha-Gal bearing cells compared to controls within 3 months after cardiac surgery. The complete absence of IB4/DAPI positive structures 12 months after implantation indicates a specific degradation of alpha-Gal bearing cells through previous exposure to the human blood circuit.


Asunto(s)
Bioprótesis , Prótesis Valvulares Cardíacas , Válvulas Cardíacas/cirugía , Inmunoglobulina G/biosíntesis , Inmunoglobulina G/inmunología , alfa-Galactosidasa/inmunología , Anciano , Animales , Especificidad de Anticuerpos , Bovinos , Ensayo de Inmunoadsorción Enzimática , Epítopos , Humanos , Inmunohistoquímica , Persona de Mediana Edad , Periodo Posoperatorio , Porcinos , Factores de Tiempo
17.
Urologe A ; 58(12): 1499-1510, 2019 Dec.
Artículo en Alemán | MEDLINE | ID: mdl-31741003

RESUMEN

The use of multiparametric magnetic resonance imaging (mpMRI) is becoming increasingly more important for the primary diagnostics of prostate cancer (PCa) and for monitoring under active surveillance. Current studies confirmed that the use of mpMRI can increase the detection of clinically significant PCa and reduce the detection rate of insignificant PCa as well as the rate of unnecessary biopsies. The information from mpMRI can be cognitively used for in-bore biopsy and using fusion biopsy systems. There are no clear recommendations on the access approach for fusion biopsy (e. g. transrectal or perineal), whereby higher rates of rectal bleeding and infections have been described for transrectal access compared to perineal access. The increasing rate of antibiotic resistance as well as restricted indications for the use of quinolones are a major challenge for transrectal biopsy.


Asunto(s)
Biopsia Guiada por Imagen , Neoplasias de la Próstata , Humanos , Imagen por Resonancia Magnética , Masculino , Estudios Prospectivos , Neoplasias de la Próstata/diagnóstico por imagen
18.
J Med Entomol ; 45(5): 832-40, 2008 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-18826024

RESUMEN

A new species of argasid tick, Ornithodoros (Alectorobius) rioplatensis Venzal, Estrada-Peña, & Mangold, is described from larval and adult specimens collected in Uruguay. Further specimens from Argentina, Paraguay, and Chile are ascribed to the new species. Key distinguishing characters of larvae of the species are the number of pairs of dorsal setae (19-20 but typically 20 in O. rioplatensis, compared with 16-17 but typically 17 in O. puertoricensis and O. talaje), and the length of the hypostome, which is clearly longer in O. rioplatensis than in O. talaje. Morphological details of the adults of these species are inadequate for taxonomic purposes. The genetic distance between O. puertoricensis and O. rioplatensis, based on 16S rDNA sequencing, is approximately 12.7%. Variability in some morphological features, using multivariate morphometric discrimination to assess congruence between populations, was examined among larval specimens of O. talaje and O. puertoricensis collected from the United States, and Central and South America. Larval specimens of O. talaje from Guatemala (near the type locality of the species) were morphologically different from Mexican and southern U.S. populations originally described as O. talaje. In the absence of DNA data for these populations, and because of inadequate statistical discrimination among body characters, we prefer to refer to the Mexican and U.S. material as O. nr. talaje until further analysis of population variability is conducted using an adequate sample size.


Asunto(s)
Ixodidae/clasificación , Ixodidae/ultraestructura , Animales , Femenino , Larva/clasificación , Larva/ultraestructura , Masculino , América del Sur
19.
Vet Parasitol ; 156(3-4): 284-92, 2008 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-18584966

RESUMEN

The therapeutic efficacies of ivermectin (subcutaneous injection) and eprinomectin (topical treatment) given at two different dosage levels to goats naturally infested with Amblyomma parvum were assessed. Treatments included subcutaneous injection of ivermectin at 0.2 and 0.4mg/kg and extra-label pour-on administration of eprinomectin at 0.5 and 1mg/kgb.w. Ivermectin and eprinomectin failed to control Amblyomma parvum on goats. Treatment with ivermectin resulted in a low number of engorged female ticks in relation to untreated control goats and, at the highest dose rate (0.4mg/kg), the female engorgement weights were significantly lower and the pre-oviposition period significantly longer than those observed in ticks recovered from untreated control goats. The tick efficacy assessment was complemented in a separate group of tick-free goats with a pharmacokinetic characterization of eprinomectin (topically administered at 0.5, 1.0 and 1.5mg/kg) and ivermectin (subcutaneous treatment given at (0.2 and 0.4mg/kg) in goats. Heparinized blood samples were taken between 0 and 21 days post-treatment. Higher and more persistent drug plasma concentrations were recovered after the subcutaneous treatment with ivermectin compared to those obtained for eprinomectin topically administered. The understanding of the relationship among the pattern of drug absorption, the kinetic disposition and the resultant clinical efficacy is relevant to improve the poor performance observed for ivermectin and eprinomectin against A. parvum on goats.


Asunto(s)
Enfermedades de las Cabras/tratamiento farmacológico , Insecticidas/uso terapéutico , Ivermectina/análogos & derivados , Ivermectina/uso terapéutico , Infestaciones por Garrapatas/veterinaria , Administración Tópica , Animales , Área Bajo la Curva , Relación Dosis-Respuesta a Droga , Femenino , Cabras , Semivida , Inyecciones Subcutáneas , Insecticidas/administración & dosificación , Insecticidas/sangre , Insecticidas/farmacocinética , Ivermectina/administración & dosificación , Ivermectina/sangre , Ivermectina/farmacocinética , Ixodidae/efectos de los fármacos , Infestaciones por Garrapatas/tratamiento farmacológico
20.
J Med Entomol ; 43(5): 801-9, 2006 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-17017212

RESUMEN

The female of Argas (Persicargas) keiransi Estrada-Peña, Venzal & González-Acuña (Acari: Argasidae) is described from specimens collected in the type locality in Chile. The female has a unique combination of characters in the dorsal cuticle and in the number and pattern of ventrolateral setae in the basis capituli. Additional features on tarsus I chaetotaxy and dorsal plate are provided for the larva of the species, as observed on flat specimens derived from engorged females collected in the type locality. Keys for the larvae of the New World Persicargas are provided as well as illustrations for prominent characters in hypostome and posterolateral setae. The mitochondrial 16S rDNA sequence of A. keiransi has been obtained, and an analysis of the phylogenetic relationships with other ticks is included. Phylogenetic analysis provides support for a Persicargas grouping of species, separated from species in Argas.


Asunto(s)
Argas/clasificación , Argas/ultraestructura , Filogenia , Américas , Animales , Argasidae/anatomía & histología , Argasidae/clasificación , Chile , Demografía , Femenino , Geografía , Larva/ultraestructura , Datos de Secuencia Molecular , ARN Ribosómico 16S/genética , Especificidad de la Especie
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