The potential use of Pseudomonas in terrestrial and space agriculture.

In the last few years, there has been an increasing interest in solutions for sustainable agriculture to reduce negative impacts on the environment resulting from modern agricultural practices. The use of environmentally beneficial bacteria, like Pseudomonas, which can increase plant productivity by reducing growth time, is a promising opportunity for sustainable agriculture. Pseudomonas is a gram-negative bacterium genus, commonly present in soils, plants, and irrigation water. Pseudomonas has a wide range of metabolic routes that could benefit agriculture, such as nutrient uptake, pathogen suppression, heavy metal solubilization, drought tolerance, and high salt concentration tolerance. Pseudomonas may even be proposed as a potential tool for future agriculture on other planets, where the use of microorganisms would be essential for crop development in hostile and inhospitable environments. Hence, the present review discusses the potential use of Pseudomonas in sustainable agriculture on planet Earth and potentially on Mars, highlighting its role in plant growth enhancement and plant protection from pathogenic microorganisms.

Photocatalytic activity enhancement of two-step and one-pot synthesis of Pd/ZnO nanocomposites: an experimental and DFT study.

Pd/ZnO nanocomposites were successfully synthesized by means of one and two pot synthesis and applied in the photodegradation of Rh6G. The nanocomposites were characterized by XRD, SEM, TEM, FTIR and micro-Raman spectroscopies. It was found the presence of PdZn2, PdO and agglomerated particles in the support surface for the Palladium-based nanocomposites fabricated by one-pot route; the two-step method allowed the formation of spherical Pd nanoparticles, with homogeneous distribution in the nanocomposite matrix, with an average size of 2.16 nm. The results show higher photocatalytic efficiency for the samples fabricated under the two-step approach compared to the one-pot synthesis. Based on experimental results, density functional theory (DFT) calculations were carried out to understand the enhancement photocatalytic of Pd/ZnO nanocomposites. To achieve it, the ZnO (001) and (101) surfaces were built and decorated by different Pd coverages. The theoretical results indicated two different photocatalytic mechanisms. In ZnO (001) case, the electrons flowed from surface to Pd, generating the superoxide radical anion (⋅O2-). Furthermore, the density of states of the ZnO (001) surface was modified by impurity Pd-d states at proximity to the conduction states, which may work as electron acceptors states. On the other hand, we found that the electrons flow from Pd to ZnO (101) surface, inducing the formation of ⋅OH and ⋅O2- for the degradation of Rh6G. The density of states of the ZnO (101) revealed a reduction in its bandgap, due to Pd-d states localized above valence states. Hence, our theoretical results suggest that the Pd-d states may facilitate the mobility of electrons and holes in (001) and (101) surfaces, respectively, reducing the rate of charge recombination.

Prevalence of flukes (Fasciola hepatica and paramphistomids) in cattle in south-eastern Mexico.

The objective of this study was to determine the risk factors and prevalence of trematodes in south-eastern Mexico. The prevalence of trematodes was determined in 1010 bovines. The study was carried out from October 2018 (n=291) to December 2019 (n=719). Only in 2019 rumen and liver fluke eggs were differentiated. Faecal samples (n=311) were obtained from farms in southeast Mexico located in Tabasco, Chiapas and Campeche. In addition, the presence of flukes in liver and rumen from slaughtered cattle in abattoirs was recorded with a total of 408 samples. A logistic procedure was used to obtain the prevalence and the effect of main risk factors such as land physiography (flooded areas and hills), year, sex, animals' age and type of sample obtained (eggs in faeces and flukes). The general prevalence of flukes in cattle was 32.3 % in 2018 and 41.7 % in 2019. Prevalence of F. hepatica (liver fluke) was 18.6 % (134/719) and that of paramphistomids (rumen fluke) was 33.4 % (240/719). The infected cattle from the slaughterhouse indicated a lower prevalence of F. hepatica (1 %) and rumen fluke (26.7 %) than in farms detected by egg in faeces (41.8 % and 42.1 %, respectively). The physiographic zone was decisive in the presence of F. hepatica and rumen fluke, while sex did not represent a risk factor (P > 0.05). The environmental conditions of the Mexican southeast favour the presence of both liver and rumen fluke.

Changes in sugar-sweetened beverage purchases across the price distribution after the implementation of a tax in Mexico: a before-and-after analysis.

BACKGROUND: A tax of one-Mexican peso per liter of sugar-sweetened beverage (SSB) came into effect in January 2014 in Mexico as a national health policy to tackle the high overweight and obesity prevalence. Previous studies have shown an overall reduction in SSB purchases after the tax implementation. However, it remains unknown whether and to what extent SSB consumers switched to cheaper taxed beverages, attenuating the potential effect of the policy. Our study's objective was to estimate changes in household purchases of taxed SSBs by tertiles of SSB prices (low, middle, and high) in urban areas after the SSB tax implementation in 2014. METHODS: Based on purchase data for 2012-2015 from households living in 54 Mexican cities with a population > 50,000 inhabitants, we calculated unit-value SSB prices for the full period and sorted them on a monthly basis to create monthly price tertiles. We merged these price tertiles to household purchases and created average monthly ml/capita/day SSB purchases by price tertile at the city level. We assessed SSB purchase switching patterns before and after the tax implementation through price-tertile stratified linear models. The main variable in the models was a dummy indicator that allowed us to identify the pre-tax period (2012-13) and post-tax period (2014-15). We controlled our models for time trends and contextual economic variables. RESULTS: In the regression adjusted models, we found a statistically significant purchase reduction ranging between 10.80 and 13.79 ml/capita/day (p-value < 0.001) across taxed beverages from the middle-price SSB after the tax implementation. We observed no statistically significant reductions in purchases of low-price SSBs and high-price SSBs. CONCLUSIONS: Our findings show purchase reductions in the middle-price SSBs, which represents ≈30% of the overall SSB purchases in urban Mexico. Future studies should be conducted to test if the redesign of the current the tax, by either doubling the tax amount or taxing sugar content, might reduce more effectively purchases across all SSBs.

Estimation of milk yield based on udder measures of Pelibuey sheep using artificial neural networks.

Udder measures have been used to assess milk yield of sheep through classical methods of estimation. Artificial neural networks (ANN) can deal with complex non-linear relationships between input and output variables. In the current study, ANN were applied to udder measures from Pelibuey ewes to estimate their milk yield and this was compared with linear regression. A total of 357 milk yield records with its corresponding udder measures were used. A supervised learning was used to train and teach the network using a two-layer ANN with seven hidden structures. The globally convergent algorithm based on the resilient backpropagation was used to calculate ANN. Goodness of fit was evaluated using the mean square prediction error (MSPE), root MSPE (RMSPE), correlation coefficient (r), Bayesian's Information Criterion (BIC), Akaike's Information Criterion (AIC) and accuracy. The 15-15 ANN architecture showed that the best predictive milk yield performance achieved an accuracy of 97.9% and the highest values of r2 (0.93), and the lowest values of MSPE (0.0023), RMSPE (0.04), AIC (- 2088.81) and BIC (- 2069.56). The study revealed that ANN is a powerful tool to estimate milk yield when udder measures are used as input variables and showed better goodness of fit in comparison with classical regression methods.

Guillain-Barre syndrome in Mexico: clinical features and validation of Brighton Collaboration Group criteria. / Síndrome de Guillain-Barré en México: características clínicas y validación de los criterios de Brighton.

INTRODUCTION: As SARS-CoV-2 vaccination is ongoing in Mexico and Guillain-Barre syndrome (GBS) cases have been reported, validation of Brighton criteria in Mexico is necessary. Moreover, epidemiology of GBS in Mexico differs from European and North American countries. OBJECTIVE: To describe the clinical, cerebrospinal and electrodiagnostic features in Mexican patients diagnosed with GBS and classify them according to the Brighton Collaboration Group diagnostic criteria. Patrients and methods. An ambispective cohort study was conducted. We included patients that fulfilled the National Institute of Neurological Disorders and Stroke (NINDS) diagnostic criteria for Guillain-Barre syndrome. Patients in this study were classified according to Brighton collaboration group levels of certainty for Guillain-Barre syndrome. RESULTS: Sixty eight percent of patients were male. Of the 248 patients included, 58.4% had history of a precedent infection, mean time from symptom onset to admission was 5 (1-30) days. Mean Medical Research Council sum score 30.3 ± 15.5. Almost 98% of patients had a monophasic course. Level 1 of certainty according to Brighton collaboration group criteria was fulfilled by 54.6% of patients, level 2 by 45% and level 4 by 0.6%. Patients meeting level 2 of certainty were mostly because normal cerebrospinal fluid findings or findings in nerve conduction studies not consistent with any GBS variants. CONCLUSION: GBS is a frequent autoimmune neuropathy that has been associated with preceding infections and with vaccination campaigns. For SARS-CoV-2 vaccination campaign in Mexico, validation of Brighton Criteria is necessary. Although Mexico's GBS epidemiology has been changing throughout recent years, this study provides similar data compared to other countries.

TITLE: Síndrome de Guillain-Barré en México: características clínicas y validación de los criterios de Brighton.Introducción. Dado que la vacunación contra el SARS-CoV-2 está en curso en México y se han notificado casos de Guillain-Barré, es necesaria la validación de los criterios de Brighton en México. La epidemiología de Guillain-Barré en México difiere de la de los países europeos y norteamericanos. Objetivo. Describir las características clínicas, cerebroespinales y electrodiagnósticas en pacientes mexicanos con diagnóstico de Guillain-Barré y clasificarlos según los criterios diagnósticos del Brighton Collaboration Group. Pacientes y métodos. Se realizó un estudio de cohorte ambispectivo. Se incluyó a pacientes que cumplen con los criterios del National Institute of Neurological Disorders and Stroke para el síndrome de Guillain-Barré (SGB). Se clasificó a los pacientes según los niveles de certeza del Brighton Collaboration Group para el SGB. Resultados. El 68% de los pacientes eran hombres. De los 248 pacientes incluidos, el 58,4% tenía antecedentes de infección previa. La media desde el inicio de los síntomas hasta el ingreso fue de 5 (1-30) días, y la puntuación media de la suma del Medical Research Council, de 30,3 ± 15,5. El nivel 1 de certeza según los criterios del Brighton Collaboration Group se cumplió en el 54,6% de los pacientes; el nivel 2, en el 45%; y el nivel 4, en el 0,6%. Los pacientes que alcanzaron el nivel 2 de certeza se debieron principalmente a hallazgos normales en el líquido cefalorraquídeo o a hallazgos en estudios de neuroconducción que no cumplen los criterios de ninguna variante de SGB. Conclusión. El SGB es una neuropatía autoinmune frecuente que se ha asociado con infecciones previas y con campañas de vacunación. Para la campaña de vacunación contra el SARS-CoV-2 en México es necesaria la validación de los criterios de Brighton. Aunque la epidemiología del SGB en México ha ido cambiando a lo largo de los últimos años, este estudio proporciona datos similares en comparación con otros países.

Effect of tannins from tropical plants on methane production from ruminants: A systematic review.

Methane (CH4) is a greenhouse gas generated during the feed fermentation processes in the rumen. However, numerous studies have been conducted to determine the capacity of plant secondary metabolites to enhance ruminal fermentation and decrease CH4 production, especially those plants rich in tannins. This review conducted a descriptive analysis and meta-analysis of the use of tannin-rich plants in tropical regions to mitigate CH4 production from livestock. The aim of this study was to analyse the effect of tannins supplementation in tropical plants on CH4 production in ruminants using a meta-analytic approach and the effect on microbial population. Sources of heterogeneity were explored using a meta-regression analysis. Final database was integrated by a total of 14 trials. The 'meta' package in R statistical software was used to conduct the meta-analyses. The covariates defined a priori in the current meta-regression were inclusion level, species (sheep, beef cattle, dairy cattle, and cross-bred heifers) and plant. Results showed that supplementation with tropical plants with tannin contents have the greatest effects on CH4 mitigation . A negative relationship was observed between the level of inclusion and CH4 emission (-0.09), which means that the effect of CH4 mitigation is increasing as the level of tannin inclusion is higher. Therefore, less CH4 production will be obtained when supplementing tropical plants in the diet with a high dose of tannins.

Guillain-Barre syndrome during COVID-19 pandemic: experience from a referral healthcare center in Mexico. / Síndrome de Guillain-Barré durante la pandemia de COVID-19: experiencia de un centro de referencia en México.

INTRODUCTION: To describe clinical characteristics and electrophysiological variants of GBS cases during the pandemic, we carried out a comparative analysis between SARS-CoV2 related GBS and non-SARS-CoV2 patients and then compared to the 2019 cases. PATIENTS AND METHODS: We carried out a cross-sectional study of GBS patients diagnosed according to Asbury and Cornblath criteria. We collected information on clinical and paraclinical variables. We defined a SARS-CoV-2 related GBS case according to the description of Ellul et al. We used Hadden criteria to classify the electrophysiological variants. We performed a comparative analysis between groups. RESULTS: Fourty-two patients were diagnosed with GBS in 2020, men 64.2%, age 46 ± 17.4 years, patients with obesity/overweight 42.8%, previous diarrhea 31%, history of respiratory tract infection 14.2%. Guillain Barre Disability Scale = 3 points 71.4% and, cranial nerve involvement 69%. The most frequent electrophysiological variant was acute inflammatory demyelinating polyradiculoneuropathy (AIDP) 53.5%. Seven (16.6%) cases were SARS-CoV2 related, four men, age 43.4 ± 13.4 years. When comparing patients with GBS in 2020 vs patients in 2019, we observed a decrease in the previous infection history during 2020 (45.2% vs 73.3%, p-value = 0.005) and a decrease in previous respiratory infection (14.2% vs 33.3%, p = 0.045), as well as a higher frequency of cranial nerve involvement, and albuminocytologic dissociation. CONCLUSIONS: SARS-CoV2 virus infection preventive measures may be impacting the presentation of post-infectious diseases such as GBS. We did not observe an increase in GBS cases during 2020. Also, the AIDP variant were more frequent in our population in the COVID-19 pandemic.

TITLE: Síndrome de Guillain-Barré durante la pandemia de COVID-19: experiencia de un centro de referencia en México.Introducción. Se trata de describir las características clínicas y variantes electrofisiológicas de los casos de síndrome de Guillain-Barré (SGB) durante la pandemia. Llevamos a cabo un análisis comparativo entre pacientes con SGB relacionado con el SARS-CoV-2 y sin antecedente del virus, y posteriormente realizamos una comparación con los casos de 2019. Pacientes y métodos. Se llevó a cabo un estudio transversal de los pacientes con diagnóstico de SGB según los criterios de Asbury y Cornblath. Se recolectaron información clínica y variables paraclínicas. Definimos el SGB relacionado con el SARS-CoV-2 conforme a la descripción de Ellul et al. Se utilizaron los criterios de Hadden para la clasificación de las variantes electrofisiológicas. Por último, realizamos un análisis comparativo entre grupos. Resultados. Se diagnosticó a 42 pacientes con SGB en 2020, un 64,2% hombres, con una edad de 46 ± 17,4 años, un 42,8% con obesidad/sobrepeso, un 31% con historia de diarrea previa y un 14,2% con infección respiratoria previa. El 71,4% tuvo una puntuación en la Guillain-Barré Disability Score igual o mayor que 3 puntos y el 69% tenía afectados los nervios del cráneo. La variante electrofisiológica más común fue la polirradiculoneuropatía desmielinizante inflamatoria aguda (PDIA; 53,5%). Siete (16,6%) casos tuvieron relación con el SARS-CoV-2, cuatro hombres, con edad de 43,4 ± 13,4 años. Al realizar la comparación entre pacientes con SGB de 2020 frente a los de 2019, observamos un decremento en el antecedente de infección previa en 2020 (45,2 frente a 73,3%; p = 0,005) y un decremento específico en la historia de infección respiratoria (14,2 frente a 33,3%; p = 0,045), así como una mayor frecuencia de afectación de los nervios del cráneo y de disociación albuminocitológica. Conclusiones. Las maniobras preventivas para la infección por el SARS-CoV-2 impactan directamente en la presentación de enfermedades postinfecciosas como el SGB. No observamos un incremento en los casos de SGB durante 2020. Asimismo, la variante de PDIA fue la más frecuente en nuestra población durante la pandemia de COVID-19.

[Vulpian-Bernhardt syndrome. Its frequency and clinical and electrophysiological features in a tertiary care centre in Mexico]. / Síndrome de Vulpian-Bernhardt. Frecuencia, características clínicas y electrofisiológicas en un centro de atención de tercer nivel en México.

INTRODUCTION: Vulpian-Bernhardt syndrome (VBS) is an atypical rare clinical phenotype of amyotrophic lateral sclerosis (ALS) that causes a significant delay in diagnosis, and thus it is important to recognise its clinical and electrophysiological features. MATERIALS AND METHODS: Retrospective cross-sectional study. We reviewed the clinical records of patients diagnosed with ALS in the period from January to December 2019. Those meeting criteria for VBS were included so as to describe their frequency as well as their clinical and electrophysiological features. RESULTS: Twenty patients (15.8%) met criteria for VBS; 55% were female; age at onset of symptoms was 46.6 ± 12.9 years; 40% were smokers; median delay in diagnosis was 24 (12-96) months; median time to involvement of the second body segment was 24 (12-132) months, which was lumbosacral in 65%; mean Revised Amyotrophic Lateral Sclerosis Functional Rating Scale score was 27 ± 7 points; 45% met the El Escorial criteria for ALS defined at diagnosis and 58.8% met the Awaji criteria. There were 19 nerve conduction studies and 17 electromyograms, and an abductor digiti minimi-abductor pollicis brevis (ADM/APB) ratio < 0.6 was found in 63% (split hand). CONCLUSIONS: There is a significant delay in the diagnosis of motor neuron diseases in general and more particularly in VBS. Calculating the ADM/APB ratio and applying the Awaji criteria in the electrophysiology study can be a valuable aid to increase diagnostic certainty in this clinical entity.

TITLE: Síndrome de Vulpian-Bernhardt. Frecuencia, características clínicas y electrofisiológicas en un centro de atención de tercer nivel en México.Introducción. El síndrome de Vulpian-Bernhardt (SVB) es un fenotipo clínico atípico e infrecuente de la esclerosis lateral amiotrófica (ELA) que condiciona un importante retraso diagnóstico, por lo que reconocer sus características clínicas y electrofisiológicas tiene relevancia. Materiales y métodos. Estudio retrospectivo y transversal. Se revisaron los expedientes clínicos de pacientes con diagnóstico de ELA en el período de enero de 2017 a diciembre de 2019. Se incluyeron los que cumplían criterios para SVB para describir su frecuencia, características clínicas y electrofisiológicas. Resultados. Veinte pacientes (15,8%) cumplieron los criterios para el SVB; el 55% eran mujeres; la edad de inicio de los síntomas era de 46,6 ± 12,9 años; presentaba tabaquismo el 40%; la mediana de retraso del diagnóstico fue de 24 (12-96) meses; la mediana en afectarse un segundo segmento corporal fue de 24 (12-132) meses, que fue el lumbosacro en el 65%; el promedio en la escala Revised Amyotrophic Lateral Sclerosis Functional Rating Scale fue de 27 ± 7 puntos; el 45% cumplía los criterios de El Escorial para ELA definida en el momento del diagnóstico y el 58,8%, los de Awaji. Se contó con 19 estudios de neuroconducción y 17 electromiogramas, y se encontró una razón abductor digiti minimi-abductor pollicis brevis (APB/ADM) menos de 0,6 en el 63% (mano dividida). Conclusiones. Existe un retraso importante en el diagnóstico de enfermedades de la motoneurona en general y de SVB en particular. Calcular la razón APB/ADM y aplicar los criterios de Awaji en el estudio de electrofisiología puede ser de gran ayuda para aumentar la certeza diagnóstica en esta entidad clínica.

Sublethal effect of Abamectin in the functional response of the predator Phytoseiulus persimilis (Athias-Henriot) on Tetranychus urticae (Koch) (Acari: Phytoseiidae, Tetranychidae) / Efeito subletal da Abamectina na resposta funcional do predador Phytoseiulus persimilis (Athias-Henriot) em Tetranychus urticae (Koch) (Acari: Phytoseiidae, Tetranychidae)

Abstract The biological control used for the control of Tetranychus urticae (Koch) is the predator mite Phytoseiulus persimilis (Athias-Henriot). It is important to the know the effects of acaricides on the biological behavior the Abamectin on the functional response of P. persimilis. The functional response of the predator was of type II exposed to concentration of Abamectin, the functional response parameters: successful attack rate (a'), handling time (Th), search efficiency and the maximum predation theory (T/Th) were affected by the acaricide. The predator spends more time in persecute, dominate, consume and prepair it self to the next searching comparing with the proof subject an the predation ability was affected.

Resumo O controle biológico utilizado para o controle de Tetranychus urticae (Koch) é o acaro predador Phytoseiulus persimilis (Athias-Henriot). É importante conhecer os efeitos dos acaricidas sobre o comportamento biológico do predador. Foi avaliado o efeito tóxico de a Abamectina na resposta funcional de P. persimilis. A resposta funcional do predador foi tipo II exposta a concentrações subletais de Abacmetina, os parâmetros da resposta funcional: taxa de ataque (a'), tempo de manipulação (Th), a eficiência na procura e predação teórica máxima (T/Th) foram afetados pelo acaricida. O predador passa mais tempo na procura, dominar, consumir e se preparar para a próxima procura em comparação com a testemunha e sua capacidade de predação foi afetada.

Sublethal effect of Abamectin in the functional response of the predator Phytoseiulus persimilis (Athias-Henriot) on Tetranychus urticae (Koch) (Acari: Phytoseiidae, Tetranychidae).

The biological control used for the control of Tetranychus urticae (Koch) is the predator mite Phytoseiulus persimilis (Athias-Henriot). It is important to the know the effects of acaricides on the biological behavior the Abamectin on the functional response of P. persimilis. The functional response of the predator was of type II exposed to concentration of Abamectin, the functional response parameters: successful attack rate (a'), handling time (Th), search efficiency and the maximum predation theory (T/Th) were affected by the acaricide. The predator spends more time in persecute, dominate, consume and prepair it self to the next searching comparing with the proof subject an the predation ability was affected.

Sublethal effect of Abamectin in the functional response of the predator Phytoseiulus persimilis (Athias-Henriot) on Tetranychus urticae (Koch) (Acari: Phytoseiidae, Tetranychidae) / Efeito subletal da Abamectina na resposta funcional do predador Phytoseiulus persimilis (Athias-Henriot) em Tetranychus urticae (Koch) (Acari: Phytoseiidae, Tetranychidae)

The biological control used for the control of Tetranychus urticae (Koch) is the predator mite Phytoseiulus persimilis (Athias-Henriot). It is important to the know the effects of acaricides on the biological behavior the Abamectin on the functional response of P. persimilis. The functional response of the predator was of type II exposed to concentration of Abamectin, the functional response parameters: successful attack rate (a), handling time (Th), search efficiency and the maximum predation theory (T/Th) were affected by the acaricide. The predator spends more time in persecute, dominate, consume and prepair it self to the next searching comparing with the proof subject an the predation ability was affected.(AU)

O controle biológico utilizado para o controle de Tetranychus urticae (Koch) é o acaro predador Phytoseiulus persimilis (Athias-Henriot). É importante conhecer os efeitos dos acaricidas sobre o comportamento biológico do predador. Foi avaliado o efeito tóxico de a Abamectina na resposta funcional de P. persimilis. A resposta funcional do predador foi tipo II exposta a concentrações subletais de Abacmetina, os parâmetros da resposta funcional: taxa de ataque (a'), tempo de manipulação (Th), a eficiência na procura e predação teórica máxima (T/Th) foram afetados pelo acaricida. O predador passa mais tempo na procura, dominar, consumir e se preparar para a próxima procura em comparação com a testemunha e sua capacidade de predação foi afetada.(AU)

Blood biochemistry of olive ridley (Lepidochelys olivacea) sea turtles foraging in northern Sinaloa, Mexico.

Blood parameters provide an excellent tool to evaluate the health status of wildlife. However, there are few studies about health parameters of sea turtles in Mexico. For olive ridley turtles (Lepidochelys olivacea), no information was available to establish the health baseline for the species. The objective of this study was to establish reference blood biochemistry values for olive ridley turtles in the northern Sinaloa foraging area. Between 2013 and 2015, 82 olive ridley turtles were captured. Body condition index (BCI) presented a mean of 1.46 ± 0.14 (1.17-2.02) that categorized the population with excellent body condition; in addition, 99% of the turtles captured had a good physical appearance. Blood was collected for biochemistry analysis from 60 turtles. Significantly higher values of total protein, albumin, A/G ratio (albumin/globulin) and PCV (packed cell volume or hematocrit) were observed in adult when compared to subadult turtles. On the other hand, no significant differences were found when females and males were compared. Based on the BCI, physical assessment, and blood parameters, and compared to other sea turtle species, olive ridley turtles in northern Sinaloa were considered in excellent health. To the best of our knowledge, this is the first study to establish normal blood biochemistry values of foraging olive ridley turtles in northern Sinaloa.

Effect of diet on carboxylesterase activity of tadpoles (Rhinella arenarum) exposed to chlorpyrifos.

An outdoor microcosm was performed with tadpoles (Rhinella arenarum) exposed to 125µgL-1 chlorpyrifos and fed two types of food, i.e., lettuce (Lactuca sativa) and a formulated commercial pellet. Acetylcholinesterase (AChE) and carboxylesterase (CbE) activities were measured in liver and intestine after 10 days of pesticide exposure. Non-exposed tadpoles fed lettuce had an intestinal AChE activity almost two-fold higher than that of pellet-fed tadpoles. No significant differences were observed, however, in liver AChE activity between diets. Likewise, intestinal CbE activity - measured using two substrates, i.e. 1-naphthyl acetate (1-NA) and 4-nitrophenyl valerate (4-NPV) - was higher in tadpoles fed lettuce than in those fed pellets. However, the diet-dependent response of liver CbE activity was opposite to that in the intestine. Chlorpyrifos caused a significant inhibition of both esterase activities, which was tissue- and diet-specific. The highest inhibition degree was found in the intestinal AChE and CbE activities of lettuce-fed tadpoles (42-78% of controls) compared with pellet-fed tadpoles (<60%). Although chlorpyrifos significantly inhibited liver CbE activity of the group fed lettuce, this effect was not observed in the group fed pellets. In general, intestinal CbE activity was more sensitive to chlorpyrifos inhibition than AChE activity. This finding, together with the high levels of basal CbE activity found in the intestine, may be understood as a detoxification system able to reduce intestinal OP uptake. Moreover, the results of this study suggest that diet is a determinant factor in toxicity testing with tadpoles to assess OP toxicity, because it modulates levels of this potential detoxifying enzyme activity.

Plate size does not affect perception of food portion size.

BACKGROUND: Evidences have suggested that larger utensils may provoke 'size-contrast illusions', influencing the perceived volume and food consumption. OBJECTIVE: To analyse the influence of plate size on the visual estimate of food portion size. METHODS: Two 400 g portions of pasta with tomato sauce were presented on two plates of different diameters (24.0 and 9.0 cm). Each participant visually estimated on an individual basis the quantities of the pasta portions (g) present on each plate. In addition, each subject classified the size of the portions on each plate as 'small', 'medium' and 'large'. The mean estimates of the amount of pasta on each plate were compared by the nonparametric Mann-Whitney. The differences in the frequencies of portion classifications between plates were evaluated by the chi-squared test. RESULTS: Forty-eight students (average 25.8 ± 8.9 years) participated in the study. There was no difference in the median amount of pasta estimated for the large and small plates (150 g; range 50-500 and 115 g; range 40-500 g, respectively). The classification of the portion size as 'large' was reported by a significantly greater number of persons when they evaluated the amount of pasta arranged on the large plate compared to the small plate (47.9 versus 22.9%, respectively; P = 0.018). CONCLUSION: The size of the plate did not influence the estimate of food portions, even though it did influence the classification of portion size.

[Cryptococcoma in the central nervous system of a non-immunocompromised patient]. / Criptococoma en el sistema nervioso central de un paciente no inmunoafectado.

INTRODUCTION: Central nervous system cryptococcosis is an important cause of morbidity and mortality in immunocompromised patients; nevertheless, its presentation in immuno-spared patients is extremely rare, giving rise to a hole different spectrum, since it is manifested like granulomatous masses named cryptococomas. AIM. To describe an intracerebral case of cryptococcoma in an immuno-spared woman in the Hospital Universitario de Santander and to discuss the most relevant topics of this pathology. CASE REPORT: A 24 years-old woman, coming to the service presenting generalized tonic-clonic seizure, fixed upward gaze, sialorrhea and lost, without any data suggesting immunosupression. The computarized tomography of skull demonstrates a mass of possible inflammatory vs. noeplasmic origin. After performing imaging the patient is taken to surgery for craniotomy with excisional biopsy. By means of hystological analysis the diagnosis of cerebral criptococcoma is made, and antimycotic therapy is started, with favorable response. Actually the patient evidences good health, and no evidence of active disease. CONCLUSIONS: The presence of masses of criptococcal origin located at the central nervous system, which origin is due to a chronic granulomatous reaction, is rarely reported; these appear in almost all cases in immunocompetent patients, in which there is of primary importance to discard all causes of cellular immune deficit. Also, the diagnosis of these injuries must be considered before the presence of intracerebral masses that show inflammatory characteristics.

First 100 liver transplants at the medico-surgical research center (CIMEQ).

In July 1999 we began a liver transplant program that to October 2005 has included 100 liver transplants in 92 patients, eight retransplants, and two combined liver and kidney grafts. Twelve transplants were in pediatric patients, who showed a 92% survival rate in the first year. Fifty-four percent of the patients were male and 46% female. The most frequent etiologies of cirrhosis were 27% hepatitis virus C, 18% alcoholic, 13% cryptogenic, and 11% autoimmune. In 95% of the patients, we preserved the retrohepatic vena cava. The bile duct was reconstructed with a Kehr tube in 46% of patients with 31% using end-to-end suture with a tutor and 15% an end-to-end suture without a tutor. A hepaticojejunostomy was performed in 8%. The immunosuppression included cyclosporine (Neoral) or Prograf combined with mycophenolate mofetil or mycophenolate sodium and steroids. The most frequent biliary complications were local anastomosis leaks (6%) and stenosis (10%). The overall 1-year survival rate was 72%.

Solid mesenchymal hamartoma in an adult: a case report.

Mesenchymal hamartoma of the liver (MHL) is an uncommon tumour composed of architecturally abnormal bile ducts in an uncommitted myxoid stroma. Most MHL are diagnosed in childhood and few cases have been reported in adults. This report describes a case of a well defined solid mass in the right lobe of the liver in a 51 year old man. Preoperative radiological examination revealed a large completely solid mass. Biopsy showed a dense fibrous stroma with hyalinisation and some bile ducts. A provisional diagnosis of MHL was made. Surgical excision was impossible and liver transplantation was undertaken. Definitive pathology confirmed the diagnosis. Review of published reports shows this to be the fourth case of MHL treated by liver transplantation.