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1.
J Helminthol ; 97: e38, 2023 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-37070359

RESUMEN

In this paper we re-describe Trichuris muris based on morphological data following isolation from two commensal rodent species, Mus musculus from Mexico and Rattus rattus from Argentina. Furthermore, we provide a molecular characterization based on mitochondrial (cytochrome c oxidase subunit 1 mitochondrial gene) and nuclear (internal transcribed spacer 2 region) markers in order to support the taxonomic identification of the studied specimens of T. muris from M. musculus. We distinguished T. muris from 29 species of Trichuris found in American rodents based on morphological and biometrical features, such as the presence of a spicular tube, length of spicule, size of proximal and distal cloacal tube and non-protrusive vulva. We suggest that spicular tube patterns can be used to classify Trichuris species in three groups. Considering that the diagnosis among the species of this genus is mainly based on morphometry, this proposal represents a relevant contribution. We provide molecular studies on two markers, making this the first contribution for T. muris in the Americas. This study makes an important contribution to the integrative taxonomy of cosmopolitan nematode species, and its correct determination from the parasitological study of commensal rodents.


Asunto(s)
Roedores , Trichuris , Ratones , Femenino , Animales , Filogenia , Argentina , Genes Mitocondriales
3.
J Dairy Sci ; 104(3): 3522-3531, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33358810

RESUMEN

Staphylococcus aureus is one of the most frequent pathogens causing intramammary infections in dairy herds. Consequently, virulence factors, pathobiology, and epidemiology of Staphylococcus aureus strains have been widely assessed through the years. Nevertheless, not much has been described about the epidemiology of Staph. aureus strains from bulk tank milk (BTM) and adherences on milking equipment (AMES), even when these strains may play a role in the quality of milk that is intended for human consumption. The objective of this study was to assess the strain diversity of 166 Staph. aureus isolates collected from 3 consecutive BTM samples, and from AMES in contact with milk from 23 Chilean dairy farms. Isolates were analyzed and typed using pulsed-field gel electrophoresis. Diversity of strains, both within and among farms, was assessed using Simpson's index of diversity (SID). On farms where Staph. aureus was isolated from both AMES and BTM (n = 8), pulsotypes were further analyzed to evaluate the role of AMES as a potential source of Staph. aureus strains in BTM. Among all Staph. aureus analyzed by pulsed-field gel electrophoresis, a total of 42 pulsotypes (19 main pulsotypes and 23 subtypes) were identified. Among dairy farms, strain diversity was highly heterogeneous (SID = 0.99). Within dairy farms, Staph. aureus strain diversity was variable (SID = 0 to 1), and 18 dairy operations (81.8%) had one pulsotype that was shared between at least 2 successive BTM samples. In those farms where Staph. aureus was isolated in both AMES and BTM (n = 8), 7 (87.5%) showed a clonal distribution of Staph. aureus strains between these 2 types of samples. The overlapping of certain Staph. aureus strains among dairy farms may point out common sources of Staph. aureus among otherwise epidemiologically unrelated farms. Indistinguishable Staph. aureus strains between AMES and BTM across dairy farms suggest that Staph. aureus-containing AMES may represent a source for BTM contamination, thus affecting milk quality. Our study highlights the role of viable Staph. aureus in AMES as a source for BTM contamination on dairy farms, and also describes the overlapping and presence of specific BTM and AMES pulsotypes among farms.


Asunto(s)
Enfermedades de los Bovinos , Mastitis Bovina , Infecciones Estafilocócicas , Animales , Biopelículas , Bovinos , Chile , Industria Lechera , Femenino , Leche , Infecciones Estafilocócicas/veterinaria , Staphylococcus aureus/genética
4.
J Dairy Sci ; 103(5): 4732-4737, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32113752

RESUMEN

Staphylococcus aureus is an important intramammary pathogen for dairy cows that also is remarkably important for public health. Multiple virulence factors can be involved simultaneously during the pathogenesis of a staphylococcal disease, including adhesion proteins, extracellular enzymes, and toxins. The main objective of this study was to assess virulence factors that are associated with cow intramammary infection (IMI) and of human health concern among Staph. aureus isolates obtained from bulk tank milk (BTM) and adherences on milking equipment surfaces. A total of 166 Staph. aureus isolates from 23 dairy farms were characterized according to their virulence profiles. For virulence factors of importance in IMI, the presence of the virulence markers thermonuclease (nuc) and coagulase (coa) and virulence genes such as fibronectin (fnbA) and intercellular adhesion (icaA, icaD) were assessed. For virulence factors of public health concern, presence of antimicrobial resistance (mecA and mecC) and enterotoxin (sea and seb) genes were analyzed. Among all Staph. aureus isolates, 5 virulence profiles were found; the profile nuc(+)coa(+)fnbA(+)icaA(+)icaD(+)mecA(-)mecC(-)sea(-)seb(-) was the most frequently observed (21 out of 23 dairy farms). No differences were found between the virulence profile frequencies of Staph. aureus from BTM and adherences on milking equipment surfaces. The virulence profiles most frequently observed included genes involved in the adherence and biofilm-forming ability of Staph. aureus, which could represent a potential advantage for the bacterium during the early stages of IMI colonization and for persistence on surfaces. Our results indicate a greater frequency of virulence factors of importance for IMI pathogenesis than virulence factors of public health concern, consistent with the dairy origin of isolates. The mecA, mecC, and seb genes were not observed among Staph. aureus isolates analyzed in this study. However, the sea gene was detected in 3 Staph. aureus isolated from BTM, thus posing a potential public health threat. Our results emphasize the importance of understanding the epidemiology and dynamics of Staph. aureus on dairy farms as a tool for the improvement of udder health and milk safety.


Asunto(s)
Biopelículas/crecimiento & desarrollo , Mastitis Bovina/microbiología , Leche/microbiología , Infecciones Estafilocócicas/veterinaria , Staphylococcus aureus/patogenicidad , Factores de Virulencia/genética , Animales , Bovinos , Chile , Coagulasa/genética , Industria Lechera/instrumentación , Enterotoxinas/genética , Granjas , Femenino , Glándulas Mamarias Animales/microbiología , Nucleasa Microcócica/genética , Infecciones Estafilocócicas/microbiología , Staphylococcus aureus/aislamiento & purificación , Staphylococcus aureus/fisiología , Virulencia
5.
Rev Neurol ; 69(3): 94-98, 2019 Aug 01.
Artículo en Español, Inglés | MEDLINE | ID: mdl-31309998

RESUMEN

INTRODUCTION: Chemotherapy-induced peripheral neuropathy is a common adverse reaction in a variety of medications frequently used for a great number of cancer treatments. This condition consists of mainly sensory-type symptoms, motor components and autonomic changes. Reported prevalence ranges from 30-68%, after the completion of chemotherapy in non-Latin American people with different populations and socioeconomic levels. AIM: To determine the prevalence of chemotherapy-induced peripheral neuropathy in a Colombian population. PATIENTS AND METHODS: A real-world evidence cross-sectional retrospective study was performed in all patients from oncological clinical centers in Colombia, which received pharmacological therapy for any cancer between January 2015 and December 2016, with taxanes (paclitaxel, docetaxel), alkylators (oxaliplatin), proteasome inhibitors (bortezomib), and epothilone B analogs (ixabepilone). RESULTS: A total of 1,551 patients in four cities were included, and 11,280 doses were applied; predominantly females (n = 1,094; 70.5%), with a mean age of 57 ± 13 years old. Paclitaxel was the most commonly prescribed drug (n = 788; 50.8%). Chemotherapy-induced peripheral neuropathy was developed in 48.9% of paclitaxel, 58.5% of oxaliplatin, 50.5% of docetaxel, 43.7% of bortezomib and 95.2% of ixabepilone patients. Thirty-three patients were treated with two of these medications simultaneously. CONCLUSIONS: Chemotherapy-induced peripheral neuropathy is a frequent adverse reaction to daily cancer therapy in Colombian patients managed with taxanes, alkylators, proteasome inhibitors, and epothilone B analogs. Hence, it is necessary to establish more successful diagnostic methods and incorporate validated scales in the routine evaluation of all patients receiving these medications in our environment.


TITLE: Prevalencia de neuropatia periferica asociada a quimioterapia en cuatro centros oncologicos de Colombia.Introduccion. La neuropatia periferica inducida por quimioterapia es una reaccion comun a una variedad de medicamentos usados en el tratamiento del cancer, que consiste principalmente en sintomas sensitivos, con componentes motores y cambios autonomicos. La prevalencia es del 30-68% despues de terminar la quimioterapia en paises no latinoamericanos. Objetivo. Determinar la prevalencia de la neuropatia periferica inducida por quimioterapia en la poblacion colombiana. Pacientes y metodos. Estudio retrospectivo con evidencia del mundo real en la totalidad de pacientes atendidos en cuatro centros oncologicos de Colombia, quienes recibieron terapia farmacologica para algun tipo de cancer entre enero de 2015 y diciembre de 2016 con taxanos (paclitaxel, docetaxel), agentes alquilantes (oxaliplatino), inhibidores de proteasoma (bortezomib) y analogos de epotilona B (ixabepilona). Resultados. Se siguio a un total de 1.551 pacientes en cuatro ciudades a quienes se les aplicaron 11.280 dosis, con predominio femenino (n = 1.094; 70,5%) y una edad media de 57 ± 13 años. El paclitaxel fue el farmaco mas prescrito (n = 788; 50,8%). La neuropatia inducida por quimioterapia se presento en el 48,9% de los pacientes con paclitaxel, el 58,5% de los pacientes con oxaliplatino, el 50,5% de los pacientes con docetaxel, el 43,7% de los pacientes con bortezomib y el 95,2% de los pacientes con ixabepilona. Se trato a 33 pacientes con dos de estos medicamentos simultaneamente. Conclusiones. La neuropatia periferica inducida por quimioterapia es una reaccion adversa frecuente en pacientes con cancer en Colombia tratados con taxanos, alquilantes, inhibidores de proteasoma e ixabepilona. Es necesario establecer metodos diagnosticos efectivos e incorporar escalas validadas en la evaluacion rutinaria de los pacientes que reciben estas medicaciones.


Asunto(s)
Antineoplásicos/efectos adversos , Enfermedades del Sistema Nervioso Periférico/inducido químicamente , Adulto , Anciano , Antineoplásicos/uso terapéutico , Bortezomib/efectos adversos , Instituciones Oncológicas/estadística & datos numéricos , Colombia/epidemiología , Estudios Transversales , Epotilonas/efectos adversos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Oxaliplatino/efectos adversos , Enfermedades del Sistema Nervioso Periférico/diagnóstico , Enfermedades del Sistema Nervioso Periférico/epidemiología , Prevalencia , Inhibidores de Proteasas/efectos adversos , Estudios Retrospectivos , Taxoides/efectos adversos
6.
Oper Dent ; 38(1): 39-47, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-22770432

RESUMEN

PURPOSE: To evaluate the effect of bur roughness on bond strength values and conditioner pattern of two-step self-etch adhesives applied on sclerotic dentin. METHODS: The roots of 48 bovine incisors were removed and the crowns were divided into four groups: the control group (CO) teeth were left untreated or the teeth were slightly roughened with coarse-, medium-, or fine-grit diamond burs. Next, the teeth were subdivided and Clearfil SE Bond (CSE) and Adper SE Bond (ASE) were applied according to the manufacturers' instructions. Composite resin (Opallis) buildups were incrementally constructed on the bonded surfaces. After storage for 24 hours in distilled water at 37°C, the teeth were sectioned into sticks (area of 0.8 mm(2)). The sticks were stressed until failure by tensile forces (0.5 mm/min). Additionally, eight bovine teeth were treated as previously described, and after adhesive application, the surface was rinsed off and examined by scanning electron microscopy to measure the relative number of open tubules (OT). Data (MPa) were analyzed by two-way analysis of variance and Tukey test (p=0.05). RESULTS: CO showed the highest bond strength values (p<0.05). As regards OT, the lowest mean was observed for CO (p<0.05) and the highest was found after application of CSE or ASE (p<0.05).


Asunto(s)
Recubrimiento Dental Adhesivo , Dentina Secundaria/ultraestructura , Recubrimientos Dentinarios/química , Diamante/química , Preparación del Diente/instrumentación , Grabado Ácido Dental/métodos , Adhesividad , Animales , Bovinos , Resinas Compuestas/química , Análisis del Estrés Dental/instrumentación , Diseño de Equipo , Ensayo de Materiales , Metacrilatos/química , Microscopía Electrónica de Rastreo , Polietilenglicoles/química , Ácidos Polimetacrílicos/química , Poliuretanos/química , Distribución Aleatoria , Cementos de Resina/química , Estrés Mecánico , Propiedades de Superficie , Temperatura , Resistencia a la Tracción , Factores de Tiempo , Agua/química
7.
Phys Rev E Stat Nonlin Soft Matter Phys ; 64(5 Pt 2): 056104, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11736011

RESUMEN

We study a one-dimensional fixed-energy version (that is, with no input or loss of particles) of Manna's stochastic sandpile model. The system has a continuous transition to an absorbing state at a critical value of the particle density, and exhibits the hallmarks of an absorbing-state phase transition, including finite-size scaling. Critical exponents are obtained from extensive simulations, which treat stationary and transient properties, and an associated interface representation. These exponents characterize the universality class of an absorbing-state phase transition with a static conserved density in one dimension; they differ from those expected at a linear-interface depinning transition in a medium with point disorder, and from those of directed percolation.

8.
Phys Rev E Stat Nonlin Soft Matter Phys ; 63(3 Pt 1): 031104, 2001 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11308627

RESUMEN

Extensive Monte Carlo simulations are performed in order to evaluate both the local (straight theta(l)) and global (straight theta(g)) persistence exponents in the Ziff-Gulari-Barshad (ZGB) [Phys. Rev. Lett. 56, 2553 (1986)] irreversible reaction model. At the second-order irreversible phase transition (IPT) we find that both the local and the global persistence exhibit power-law behavior with a crossover between two different time regimes. On the other hand, at the ZGB first-order IPT, active sites are short lived and the persistence decays more abruptly; it is not clear whether it shows power-law behavior or not. In order to analyze universality issues, we have also studied another model with absorbing states, the contact process, and evaluated the local persistence exponent in dimensions from 1 to 4. A striking apparent superuniversality is reported: the local persistence exponent seems to coincide in both one- and two-dimensional systems. Some other aspects of persistence in systems with absorbing states are also analyzed.

9.
Childs Nerv Syst ; 15(6-7): 318-21, 1999 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10461780

RESUMEN

With the object of evaluating different epidemiological factors in the acute phase of head injury (HI) in the pediatric age group in five countries (Argentina, Brazil, France, Hong-Kong and Spain), we carried out a prospective and descriptive study, in which we analyzed the clinical and radiological risk factors versus management and outcome 7-30 days after trauma. We included all children seen in the emergency department and hospitalized who were aged between 0 and 15 years and had sustained HI. Data were compiled from the clinical records and analyzed for neurological evaluation with the Glasgow Coma Scale (GCS) and the Glasgow Paediatric Coma Score (GPCS), and also by means of dynamics, symptoms, skull X-rays, CT scans. The total of 2478 patients enrolled in the study was made up of 60.9% boys and 39.1 % girls. Age distribution was as follows: 55.2% aged 0-4 years; 28.3% aged 5-9 years, and 16.4% aged 10-15 years. Most (75.3%, or 1768) of these patients completed follow-up. The total sample included 1058 children (42.7%) who required hospitalization. Skull fractures were identified in 11.8% (298) of the cases, and 6.4% (158) of CT scans were pathologic. Minor HI accounted for 56.4% of these children, moderate HI for 38.9%, and severe HI for the remaining 4.7%. The lethality rate was 1.6%. Our preliminary data reveal that it is very important for new guidelines on the treatment of minor HI to be prepared, because patients with minor HI had undergone the most skull X-rays and also most frequently been admitted to hospital for unnecessarily long periods of time, though the incidence of brain damage (1.6%) was lowest in this group of the study population. We intend to carry out a full analysis of the various risk factors at the end of the study.


Asunto(s)
Traumatismos Craneocerebrales/diagnóstico , Traumatismos Craneocerebrales/epidemiología , Adolescente , Distribución por Edad , Argentina/epidemiología , Lesiones Encefálicas/diagnóstico , Lesiones Encefálicas/epidemiología , Brasil/epidemiología , Niño , Preescolar , Traumatismos Craneocerebrales/diagnóstico por imagen , Traumatismos Craneocerebrales/mortalidad , Traumatismos Craneocerebrales/terapia , Femenino , Francia/epidemiología , Hong Kong/epidemiología , Humanos , Incidencia , Lactante , Recién Nacido , Masculino , Estudios Prospectivos , Factores de Riesgo , Fracturas Craneales/diagnóstico por imagen , España/epidemiología , Tasa de Supervivencia , Tomografía Computarizada por Rayos X , Índices de Gravedad del Trauma , Resultado del Tratamiento
10.
Genet. mol. biol ; Genet. mol. biol;21(1): 139-44, Mar. 1998. tab
Artículo en Inglés | LILACS | ID: lil-238889

RESUMEN

A populaçäo urbana Chilena contemporânea deriva da mistura de ameríndios nativos com espanhóis, apresentando uma incidência média de fissura labial näo sindrômica associada ou näo a fissura palativa (NSCLP) de 1,8 por 1000 nascimentos vivos. A análise de segregaçäo complexa usando o programa de computador POINTER foi feita em 249 pedigrees estendidos, distribuídos em 202 famílias simplex e 47 famílias multiplex obtidas de probands de NSCLP afetados (157 homens e 92 mulheres). Esses pedigrees deram origem a 326 indivíduos afetados e mais de 1454 parentes. Oito modelos hipotéticos foram examinados e comparados pelo teste X²log2 razäo de máxima verossimilhança. Os modelos que postulam que NSCLP näo era transmitida nestas famílias foram rejeitados, assim como os modelos que postulam apenas um componente multifatorial (P<0,0001). O modelo que postula näo haver componente poligênico para a transmissäo do efeito mais importante foi rejeitado (P<0,0001). Entre os modelos do locus mais importante apenas o modelo recessivo de transmissäo foi rejeitado, enquanto que as heranças codominante e dominante sem um componente multifatorial näo puderam ser excluídas. O modelo näo restrito sugere que a freqüência do alelo de suscetibilidade a NSCLP no locus mais importante é 0,0037 e sua penetrância é de 92 por cento.


Asunto(s)
Humanos , Masculino , Femenino , Niño , Adulto , Labio Leporino/genética , Fisura del Paladar/genética , Chile , Variación Genética , Modelos Genéticos , Linaje
12.
Rev Med Panama ; 21(3): 107-12, 1996 Sep.
Artículo en Español | MEDLINE | ID: mdl-9280923

RESUMEN

The records of 96 patients with sickle cell disease were studied in relation to various immunological parameters. Age, sex, levels of total and fractionated serum protein and immunoglobulins, serum complements, antierythrocytic antibodies, circulating immune complexes, antiviral antibodies and lymphoid populations were taken into account. No major alterations in humoral immunity were found in this group of panamanian sickle cell patient.


Asunto(s)
Anemia de Células Falciformes/inmunología , Adolescente , Adulto , Formación de Anticuerpos , Niño , Femenino , Humanos , Inmunoglobulinas/sangre , Masculino , Estudios Prospectivos
13.
Rev. méd. Panamá ; 21(3): 107-112, Sept. 1996.
Artículo en Español | LILACS | ID: lil-409867

RESUMEN

The records of 96 patients with sickle cell disease were studied in relation to various immunological parameters. Age, sex, levels of total and fractionated serum protein and immunoglobulins, serum complements, antierythrocytic antibodies, circulating immune complexes, antiviral antibodies and lymphoid populations were taken into account. No major alterations in humoral immunity were found in this group of panamanian sickle cell patient


Asunto(s)
Humanos , Masculino , Femenino , Niño , Adolescente , Adulto , Anemia de Células Falciformes/inmunología , Estudios Prospectivos , Formación de Anticuerpos , Inmunoglobulinas/sangre
14.
Rev Med Chil ; 121(10): 1118-22, 1993 Oct.
Artículo en Español | MEDLINE | ID: mdl-8191114

RESUMEN

The aim of this work was to study the influence of cholelithiasis and cholecystectomy on duodenogastric biliary reflux. Total bile acid concentration (TBAC) in fasting gastric juice was measured in 23 consecutive patients with cholelithiasis and functioning gallbladder before and at least 3 months after cholecystectomy (group 1) and in 14 healthy volunteers (group II). In group two, TBAC was 8.5 +/- 2.8 uMol/l (mean +/- sem), the preoperative value in group I was 32.8 +/- 8.9 uMol/l and the postoperative value 69.9 +/- 14 uMol/l (p < 0.002 compared with group II and < 0.035 compared with preoperative values). These results suggest that cholelithiasis, even with a functioning gallbladder is associated with a significant increase in bile reflux to the stomach, with raises further after cholecystectomy.


Asunto(s)
Colecistectomía , Colelitiasis/fisiopatología , Reflujo Duodenogástrico/fisiopatología , Adulto , Anciano , Ácidos y Sales Biliares/análisis , Colelitiasis/cirugía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Estómago/química
16.
Rev Med Chil ; 120(9): 978-85, 1992 Sep.
Artículo en Español | MEDLINE | ID: mdl-1340990

RESUMEN

The familial association of epilepsy and cleft lip with or without cleft palate (CL (P)) is analyzed assuming both entities share common genetic predisposing factors. The genealogical data stemming from 169 CL (P) probands and 168 epileptic probands yielded information on the prevalence rates of cleft and epileptic relatives. The working hypothesis assumes that the relatives of epileptic and cleft probands should have a greater liability to CL (P) and epilepsy, respectively. The results obtained do not support the hypothesis of an etiologic association given that a greater joint prevalence of epileptic and cleft relatives is only observed when the proband is epileptic and not with a cleft proband. This situation seems to reflect a teratogenic effect of the epileptic genotype which expresses itself in those individuals which simultaneously present a greater liability to cleft.


Asunto(s)
Labio Leporino/genética , Fisura del Paladar/genética , Epilepsia/genética , Labio Leporino/complicaciones , Fisura del Paladar/complicaciones , Epilepsia/complicaciones , Femenino , Humanos , Masculino
17.
Rev Med Chil ; 120(1): 13-9, 1992 Jan.
Artículo en Español | MEDLINE | ID: mdl-1305304

RESUMEN

Eight cephalometric parameters were determined in individuals affected with cleft lip and cleft palate, their parents and siblings and a sample of normal individuals. No differences were found in males in any group. In contrast, affected females had lower measurements than their female relatives, and these lower latter in turn had measurements than control females. Although differences between groups were significant enough overlap existed and therefore genetic counseling based on these measurements would be uncertain.


Asunto(s)
Cefalometría/métodos , Labio Leporino/genética , Fisura del Paladar/genética , Adolescente , Factores de Edad , Análisis de Varianza , Estudios de Casos y Controles , Niño , Chile , Labio Leporino/patología , Fisura del Paladar/patología , Femenino , Asesoramiento Genético , Humanos , Masculino , Factores Sexuales
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