EVALUACIÓN DE MEZCLAS PARA SUSTRATO Y PRODUCCIÓN DE Pleurotus ostreatus (Jacq. ex Fr.) P. Kumm

The pulp of Agave salmiana ssp. crassispina and Agave angustifolia ssp. tequilana var. azul, byproduct of the mezcal industry, was evaluated in different treatments with wheat bran, pine shavings, walnut shavings, cedar shavings and oats straw, used as substrate for the cultivation of Pleurotus ostreatus, determining what mixture is the most adequate to cultivate the mushroom. A bromatological analysis was performed for each treatment at the beginning of the cultivation, determining the variables of moisture, ash, raw fiber, raw protein, lipids, total reducing sugars, as well as quantifying the biological efficiency of P. ostreatus. It was analyzed statistically through the HSD Tukey test, finding that the mixture of pulp of A. angustifolia ssp. tequilana var. azul mixed with 30 % of walnut shavings and 5% of wheat bran obtained a biological efficiency of 33.24 %.Se evaluó el bagazo de Agave salmiana ssp. crassispina y Agave angustifolia ssp. tequilana var. azul, subproducto de la industria del mezcal, en diferentes tratamientos con salvado de trigo, viruta de pino, viruta de nogal, viruta de cedro y paja de avena, usado como sustrato para el cultivo de Pleurotus ostreatus; determinando cual mezcla es la más adecuadas para el cultivo del hongo. Se realizó análisis bromatológico a cada tratamiento al inicio del cultivo, determinando las variables de humedad, cenizas, fibra cruda, proteína cruda, lípidos, azúcares reductores totales; así como cuantificación de la eficiencia biológica de P. ostreatus. Se analizó estadísticamente mediante la prueba HSD de Tukey, registrando que la mezcla bagazo de A. angustifolia ssp. tequilana var. azul mezclado con 30% de viruta de nogal y 5% de salvado de trigo, obtuvo la eficiencia biológica de 33.24%

Analysis of a new strain of Euphorbia mosaic virus with distinct replication specificity unveils a lineage of begomoviruses with short Rep sequences in the DNA-B intergenic region

<p>Abstract</p> <p>Background</p> <p><it>Euphorbia mosaic virus </it>(EuMV) is a member of the SLCV clade, a lineage of New World begomoviruses that display distinctive features in their replication-associated protein (Rep) and virion-strand replication origin. The first entirely characterized EuMV isolate is native from Yucatan Peninsula, Mexico; subsequently, EuMV was detected in weeds and pepper plants from another region of Mexico, and partial DNA-A sequences revealed significant differences in their putative replication specificity determinants with respect to EuMV-YP. This study was aimed to investigate the replication compatibility between two EuMV isolates from the same country.</p> <p>Results</p> <p>A new isolate of EuMV was obtained from pepper plants collected at Jalisco, Mexico. Full-length clones of both genomic components of EuMV-Jal were biolistically inoculated into plants of three different species, which developed symptoms indistinguishable from those induced by EuMV-YP. Pseudorecombination experiments with EuMV-Jal and EuMV-YP genomic components demonstrated that these viruses do not form infectious reassortants in <it>Nicotiana benthamiana</it>, presumably because of Rep-iteron incompatibility. Sequence analysis of the EuMV-Jal DNA-B intergenic region (IR) led to the unexpected discovery of a 35-nt-long sequence that is identical to a segment of the <it>rep </it>gene in the cognate viral DNA-A. Similar short <it>rep </it>sequences ranging from 35- to 51-nt in length were identified in all EuMV isolates and in three distinct viruses from South America related to EuMV. These short <it>rep </it>sequences in the DNA-B IR are positioned downstream to a ~160-nt non-coding domain highly similar to the CP promoter of begomoviruses belonging to the SLCV clade.</p> <p>Conclusions</p> <p>EuMV strains are not compatible in replication, indicating that this begomovirus species probably is not a replicating lineage in nature. The genomic analysis of EuMV-Jal led to the discovery of a subgroup of SLCV clade viruses that contain in the non-coding region of their DNA-B component, short <it>rep </it>gene sequences located downstream to a <it>CP</it>-promoter-like domain. This assemblage of DNA-A-related sequences within the DNA-B IR is reminiscent of polyomavirus microRNAs and could be involved in the posttranscriptional regulation of the cognate viral <it>rep </it>gene, an intriguing possibility that should be experimentally explored</p

Macro-mineral concentrations in soil and forage in three grassland sites at Zacatecas

Mineral concentration in forage is an important factor for extensive livestock production. Therefore, a study was performed in order to evaluate the soil mineral contents and their relationships with forage mineral concentrations taking into account three grassland sites located at Zacatecas state, México. Soil organic matter (OM) content and pH as well as soil and forage contents of Ca, P, Mg, Na and K were estimated. Soil OM contents were not different (P>0.05) among sites averaging 2.99 %. Soil pH of site 2 was higher (P£0.05) than those of sites 1 and 3. Soil of site 2 had higher P, Ca and Mg concentrations than the minimum contents used as references. Soil contents of Na and K were lower than the reference contents suggesting deficiencies in all three sites. Considering requirements for growing cattle, P, Ca and Na were at insufficient levels in forage from all three sites. Significant correlations (r Pearson) suggest a positive effect of soil P content on forage P and Mg concentrations. Soil P content could affect forage Ca concentration and Ca:P ratio. Other correlations suggest soil Ca negative effects on forage Ca concentration and Ca:P ratio.

Implicaciones del uso de clorhidrato de clenbuterol en la producción pecuaria

El objetivo del presente trabajo es resaltar la importancia y el riesgo que tiene en salud pública el consumir productos contaminados con clorhidrato de clenbuterol (CCL). En los sistemas de producción animal actuales se hace uso una gran cantidad de sustancias que son adicionadas o incluidas dentro de la alimentación de diferentes especies productivas con el interés de mejorar los parámetros productivos reproductivos, descuidando el aspecto de inocuidad. El CCL es un aditivo sintético perteneciente a una clase de medicamentos análogos fisiológicamente a la adrenalina. Químicamente se describe como polvo blanco, anhidro, muy soluble en agua y altamente estable a temperatura ambiente. En el humano se utiliza como un medicamento broncodilatador para el tratamiento del asma y en físico culturismo es utilizado por el efecto anabólico que provoca. Es un compuesto utilizado en forma clandestina en animales de ceba destinados para el consumo humano, sin respetar el periodo de retiro antes del sacrificio. El efecto de la administración oral en el ganado, cerdos, ovinos y aves modifica e incrementa el crecimiento por aumento de la masa muscular y disminución de la acumulación de grasa; puede provocar un depósito en diferentes órganos, principalmente en hígado; esta acumulación puede provocar intoxicación en las personas que consuman dicho tejido, los signos clínicos reportados, son: taquicardia, temblor y dolor muscular, mareos, cefalea, incremento en la presión sanguínea, enfermedades tiroideas, alergias, y provocar la muerte por falla cardiaca. Por las repercusiones y problemas en salud pública que produce el CCL se deben mantener programas de vigilancia epidemiológica para el control y erradicación del uso de esta sustancia en la producción animal

The impact of surgical delay on resectability of colorectal cancer: An international prospective cohort study

AimThe SARS-CoV-2 pandemic has provided a unique opportunity to explore the impact of surgical delays on cancer resectability. This study aimed to compare resectability for colorectal cancer patients undergoing delayed versus non-delayed surgery.MethodsThis was an international prospective cohort study of consecutive colorectal cancer patients with a decision for curative surgery (January-April 2020). Surgical delay was defined as an operation taking place more than 4 weeks after treatment decision, in a patient who did not receive neoadjuvant therapy. A subgroup analysis explored the effects of delay in elective patients only. The impact of longer delays was explored in a sensitivity analysis. The primary outcome was complete resection, defined as curative resection with an R0 margin.ResultsOverall, 5453 patients from 304 hospitals in 47 countries were included, of whom 6.6% (358/5453) did not receive their planned operation. Of the 4304 operated patients without neoadjuvant therapy, 40.5% (1744/4304) were delayed beyond 4 weeks. Delayed patients were more likely to be older, men, more comorbid, have higher body mass index and have rectal cancer and early stage disease. Delayed patients had higher unadjusted rates of complete resection (93.7% vs. 91.9%, P = 0.032) and lower rates of emergency surgery (4.5% vs. 22.5%, P ConclusionOne in 15 colorectal cancer patients did not receive their planned operation during the first wave of COVID-19. Surgical delay did not appear to compromise resectability, raising the hypothesis that any reduction in long-term survival attributable to delays is likely to be due to micro-metastatic disease