Association between serum calcium levels and the presentation of postpartum endometritis in housed dairy cows.

The present work aims to identify the minimum threshold of serum calcium (SC) values in cows during the first week postpartum and evaluate their relationship with the presentation of endometritis in housed dairy cows. In this prospective longitudinal observational study, 467 cows from 3 farms in Lima-Peru were studied. Blood samples were collected from cows during the first week postpartum. Endometritis was diagnosed on day 35 ± 3 days postpartum by evaluation of vaginal discharge samples. The samples were obtained using the MetricheckTM device (Simcro, New Zealand). Two cut-off points were used to diagnose endometritis: a) endometritis metricheck score ≥ 3, and b) endometritis metricheck score ≥ 2. In the univariate model that considers a SC threshold of 5.25 to 8.75 mg/dL (1.31 to 2.18 mmol/L), a significant relationship (p < 0.05) was found for endometritis metricheck score ≥ 3, while no significant relationship was found (p = 0.12) with endometritis metricheck score ≥ 2. In both cases, the optimal SC threshold for the appearance of endometritis was determined to be a value ≥7.0 mg/dL (≥1.75 mmol/L). In the logistic regression models (parity, calving season, calcium level, and their interaction), only two variables were retained, parity and calcium level (p < 0.10). It was found that the probability of having endometritis metricheck score ≥ 3 was 1.9 (95% CI: 1.1 to 3.1), whereas the probability of having endometritis metricheck score ≥ 2 was 1.5 (95% CI: 1.0 to 2.5) in cows with calcium levels <7.0 mg/dL (<1.75 mmol/L). In conclusion, cows with calcium levels <7.0 mg/dL (<1.75 mmol/L) have a 1.9-fold greater risk of developing endometritis metricheck score ≥ 3 in the first week postpartum.

Reproductive versatility and the epigenetic control of female gametogenesis.

Each year, plants and animals perform the task of repopulating the planet through patterns of courtship and mating that have a unifying and compelling logic: the production of offspring. Although life of nearly all organisms is organized around sex and breeding, Darwinian thinking focused more on the struggle for existence than on evolutionary significance of this frantic race to reproduce. In Darwin's own words, "We do not know the final cause of sexuality; why new beings should be produced by the union of the two sexual elements. The whole subject is hidden in darkness…" (Darwin 1862). In plants, a major consequence of this search for survival is the evolution of a multitude of reproductive alternatives that have intrigued botanists, geneticists, and evolutionary biologists for more than 100 years. Because sexually derived genetic diversity is interpreted as essential for adaptation, it is often thought that sex is necessary for the perpetuation of a species; however, many organisms--including several hundred families of flowering plants--are going efficiently about propagating their kind without bothering with meiosis and mating. Whereas many plants can undergo vegetative propagation, through the production of stolons, bulbs, or rhizomes, for example, many others have developed methods to produce an embryo from a single cell whose nucleus is not formed by the fusion of two gametes, offering a direct developmental and evolutionary challenge to sexual reproduction. Recent evidence suggests that epigenetic mechanisms that control transcriptional silencing of DNA repetitive elements and heterochromatin are crucial for the acquisition of cell identity in the ovule, opening the possibility that the developmental distinction between sexual development and apomixis might have evolved as an adaptive response to evolutionary forces that modulate structural variation and reproductive versatility in flowering plants.

Cramér-Rao bounds on the performance of simulated annealing and genetic algorithms in EEG source localization.

In this paper, we evaluate the performance of simulated annealing (SA) and the genetic algorithm (GA) when used for electroencephalographic (EEG) source localization. The performance is evaluated on the variance of the estimated localizations as a function of the optimization's initialization parameters and the signal-to-noise ratio (SNR). We use the concentrated likelihood function (CLF) as objective function and the Cramér-Rao bound (CRB) as a reference on the performance. The CRB sets the lower limit on the variance of our estimated values. Then, our simulations on realistic EEG data show that both SA and GA are highly sensitive to noise, but adjustments on their parameters for a fixed SNR value do not improve performance significantly. Our results also confirm that SA is more sensitive to noise and its performance may be affected by correlated sources.

Randomized, double-blind clinical trial of topical imiquimod 5% with parenteral meglumine antimoniate in the treatment of cutaneous leishmaniasis in Peru.

BACKGROUND: Current treatments for cutaneous leishmaniasis are limited by their toxicity, high cost, and discomfort and the emergence of drug resistance. New approaches, including combination therapies, are urgently needed. We performed a double-blind, randomized trial of therapy with parenteral antimony plus topical imiquimod, an innate immune-response modulator, versus therapy with antimony alone, in subjects with cutaneous leishmaniasis for whom an initial course of antimony therapy had failed. METHODS: Forty subjects with clinical resistance to antimony were recruited in Lima, Peru, between February 2001 and December 2002. All subjects received meglumine antimoniate (20 mg/kg/day im or iv) and were randomized to receive either topical imiquimod 5% cream (Aldara; 3M Pharmaceuticals) or vehicle control every other day for 20 days. Lesions and adverse events were evaluated during treatment and at 1, 2, 3, 6, and 12 months after the treatment period. RESULTS: The mean number of lesions was 1.2 per person; 71% of the lesions were facial and 76% were ulcerative. There were no major differences between the groups, and all but 2 subjects completed therapy. Mild adverse events were reported by 73% of the subjects, but only erythema occurred more commonly in the imiquimod group (P < or = .02). Lesions resolved more rapidly in the imiquimod group: 50% of the imiquimod group achieved cure at 1 month after the treatment period versus 15% of the vehicle cream group (P < or = .02); 61% of the imiquimod group at 2 months versus 25% of the vehicle cream group (P < or = .03); and 72% of the imiquimod group at 3 months versus 35% of the vehicle cream group (P < or = .02). Residual scarring in the imiquimod group was less prominent than in the vehicle cream group. CONCLUSIONS: Combined antimony plus imiquimod treatment was well tolerated, accelerated healing of lesions, and improved scar quality. This therapy may have particular advantages for subjects with facial lesions.

Successful treatment of drug-resistant cutaneous leishmaniasis in humans by use of imiquimod, an immunomodulator.

Treatment failures for leishmaniasis with pentavalent antimonials, including meglumine antimonate, are increasingly common in many endemic areas. Imiquimod (Aldara; 3M Pharmaceuticals) is a novel immune response-activating compound, approved by the United States Food and Drug Administration, that is currently used to treat cervical warts and has been shown to activate macrophage killing of Leishmania species. Therefore, an open-label, prospective study was conducted of combined imiquimod plus meglumine antimonate therapy in 12 patients with cutaneous leishmaniasis who had previously not responded to meglumine antimonate therapy. All of the patients responded well to this combination therapy, and 90% were found to be cured at the 6-month follow-up period.

Trypanosoma cruzi infection of squirrel monkeys: comparison of blood smear examination, commercial enzyme-linked immunosorbent assay, and polymerase chain reaction analysis as screening tests for evaluation of monkey-related injuries.

BACKGROUND AND PURPOSE: Wild-caught New World monkeys (NWM) from Central or South America are often infected with Trypanosoma species, including T. cruzi. In humans, T. cruzi causes Chagas' disease. Even in closed monkey colonies, T. cruzi can be propagated by blood-to-blood exposure, sexual activity, and transplacental transmission. Animal handlers and laboratory staff who deal with blood and tissues from infected NWM are at riskfor acquiring Chagas' disease via accidental exposure. METHODS: We screened 162 blood samples from wild-caught Saimiri sp. monkeys for Trypanosoma species infections by use of blood smear examination, ELISA, and polymerase chain reaction (PCR) analysis. Blood samples from 19 employees with recent history of monkey-associated injuries also were tested. RESULTS: Six percent (10/162) of the monkey samples were T. cruzi positive on the basis of blood smear examination results, 10.4% (17/162) were positive by ELISA results, and 26.5% (43/162) were positive by PCR results. Other organisms identified by PCR analysis included T. rangeli in two animals, Plasmodium spp. in two animals (P. malariae confirmed by PCR results) and microfilariae in one animal (morphologically, Mansonella perstans). Evidence of trypanosome infection was not found in the 19 employee samples on the basis of results of any of the three aforementioned tests. CONCLUSIONS: Close attention must be paid to worker safety where wild-caught NWM are used. The PCR analysis has a clear advantage over conventional techniques (ELISA, blood smear) for screening NWM for trypanosome infections during quarantine and after employee injury.

Control de calidad en laboratorios de análisis clínicos a través de un programa de intervención educativa / Quality assessment in clinical laboratories throught on educative program

Estudios previos dirigidos a conocer el estado de calidad en química clínica de los laboratorios en Paraguay, revelaron inexactitud en los resultados y falta de conocimientos en control de calidad. Esto llevó a realizar este estudio de diseño experimental, con el objeto de investigar si cambia la calidad de los resultados emitidos por los laboratorios del Area Metropolitana de Asunción, con un programa educativo en control de calidad, con y sin seguimiento sistemático a los laboratorios participantes. De los 71 laboratorios participantes el 25 por ciento (18/17) fueron públicos y el 75 por ciento (53/71) fueron privados, de un total de 150 laboratorios registrados. Por selección al azar, 37 laboratorios conformaron el grupo de intervención con seguimiento y los 34 restantes del conjunto el grupo de intervención sin seguimiento. Las mediciones realizadas al inicio del estudio, a los 6 y 12 meses post-intervención fueron, el nivel de conocimiento del bioquímico responsable designado por el laboratorio y el nivel de exactitud de los resultados emitidos. Teniendo como instrumentos, un cuestionario de autorreporte y una encuesta serológica de exactitud. Las medidas de intervención proporcionadas a ambos grupos fueron, un manual y un curso básico de control de calidad interna en química clínica. El grupo de intervención con seguimiento recibió, además, jornadas teórico prácticas y material de control para implementar un control interno de precisión. En las mediciones realizadas al inicio del estudio no hubo diferencia en los grupos de intervención, detectándose 65 por ciento resultados insatisfactorios en exactitud y 53 por ciento de profesionales con resultados insatisfactorios en conocimientos de control de calidad. En las mediciones realizadas a los 6 y 12 meses en los 71 laboratorios, sin distinción de grupo, mejoró el nivel de conocimiento (p < 0,05). Lo que constata que el programa educativo empleado fue bueno. En las mediciones del nivel de exactitud no cambiaron los resultados en los grupos de estudio (p > 0,05). Sin embargo, el grupo con seguimiento sistemático, tuvo un incremento de los resultados satisfactorios de 32 por ciento a 41 por ciento y 38 por ciento respectivamente, sin ser estadísticamente significativo (p > 0,05). Los que mejoraron su exactitud fueron aquellos que ya trabajaban con precisión e implementaron medidas preventivas y correctivas en el trabajo diario. Mientras que en los laboratorios que no mejoraron, detectamos problemas de mala organización administrativa y falta de interés en adoptar medidas de control. Los resultados de este estudio sugieren que la duración del seguimiento sistemático educativo fue probablemente insuficiente para que el profesional de nuestro país adopte sistemas de control de calidad en el laboratorio y así poder mejorar la exactitud de los resultados emitidos. Siendo probablemente necesaria una educación continua que se inicie a nivel pregrado

Control de calidad en laboratorios de análisis clínicos a través de un programa de intervención educativa / Quality assessment in clinical laboratories throught on educative program

Estudios previos dirigidos a conocer el estado de calidad en química clínica de los laboratorios en Paraguay, revelaron inexactitud en los resultados y falta de conocimientos en control de calidad. Esto llevó a realizar este estudio de diseño experimental, con el objeto de investigar si cambia la calidad de los resultados emitidos por los laboratorios del Area Metropolitana de Asunción, con un programa educativo en control de calidad, con y sin seguimiento sistemático a los laboratorios participantes. De los 71 laboratorios participantes el 25 por ciento (18/17) fueron públicos y el 75 por ciento (53/71) fueron privados, de un total de 150 laboratorios registrados. Por selección al azar, 37 laboratorios conformaron el grupo de intervención con seguimiento y los 34 restantes del conjunto el grupo de intervención sin seguimiento. Las mediciones realizadas al inicio del estudio, a los 6 y 12 meses post-intervención fueron, el nivel de conocimiento del bioquímico responsable designado por el laboratorio y el nivel de exactitud de los resultados emitidos. Teniendo como instrumentos, un cuestionario de autorreporte y una encuesta serológica de exactitud. Las medidas de intervención proporcionadas a ambos grupos fueron, un manual y un curso básico de control de calidad interna en química clínica. El grupo de intervención con seguimiento recibió, además, jornadas teórico prácticas y material de control para implementar un control interno de precisión. En las mediciones realizadas al inicio del estudio no hubo diferencia en los grupos de intervención, detectándose 65 por ciento resultados insatisfactorios en exactitud y 53 por ciento de profesionales con resultados insatisfactorios en conocimientos de control de calidad. En las mediciones realizadas a los 6 y 12 meses en los 71 laboratorios, sin distinción de grupo, mejoró el nivel de conocimiento (p < 0,05). Lo que constata que el programa educativo empleado fue bueno. En las mediciones del nivel de exactitud no cambiaron los resultados en los grupos de estudio (p > 0,05). Sin embargo, el grupo con seguimiento sistemático, tuvo un incremento de los resultados satisfactorios de 32 por ciento a 41 por ciento y 38 por ciento respectivamente, sin ser estadísticamente significativo (p > 0,05). Los que mejoraron su exactitud fueron aquellos que ya trabajaban con precisión e implementaron medidas preventivas y correctivas en el trabajo diario. Mientras que en los laboratorios que no mejoraron, detectamos problemas de mala organización administrativa y falta de interés en adoptar medidas de control. Los resultados de este estudio sugieren que la duración del seguimiento sistemático educativo fue probablemente insuficiente para que el profesional de nuestro país adopte sistemas de control de calidad en el laboratorio y así poder mejorar la exactitud de los resultados emitidos. Siendo probablemente necesaria una educación continua que se inicie a nivel pregrado (AU)