Description of a hamartoma-type odontoma in Angelfish (Pterophyllum scalare)

Archivo de memoriaFish present the same variety of tumors as described in mammals and birds. Odontogenic tumors are related to alterations in epithelial and/or mesenchymal tissues involved in the formation and development of teeth. Histologically, the odontoma is a tumor characterized by abortive tooth formations and dental tissues (i.e. enamel, dentin, and cementum) that are normally formed but present a more or less disorganized pattern. In small fish species, odontogenic tumors have almost exclusively been described in angelfish (Pterophyllum scalare) and ocellaris clownfish (Amphiprion ocellaris). These tumors are macroscopically characterized as a nodular mass located in the frontal regions of the mouth. In angelfish these tumors have been described only as individual cases either as lip fibroma (in captive specimens) or as ameloblastoma (in wild specimens), but in this report we describe the occurrence of tumors in the frontal region of the mouth in a group of twenty aquarium angelfish.Conacyt, proyecto 287537 (UAEM 4618-2018-C

El efecto de los agroquimicos sobre las abejas meliferas (Apis mellifera) y su relación con el síndrome del colapso de las colonias

The role of bees in agroecosystems is extremely important because they act as natural pollinating agents of both economically important crops and wild plants; which guarantees the production of food and the conservation of biodiversity. In addition, beekeeping represents one of the sectors that obtain the most economic income from the sale and export of honey. However, this sector has multiple problems in its production system, pests, and diseases that have affected them and has caused declines in the number of colonies and a decrease in honey production. Added to this, in the recent years there has been a spontaneous disappearance of bees,without being able to give a convincing explanation; This phenomenon is known as colony collapse disorder or CCD by its acronym in English. One of the factors that affect and cause the collapse of the colonies is the use of agrochemicals, mainly insecticides of the group of neonicotinoids. These insecticides are derivatives of nicotine and when applied to control crop pests also affect the nervous system of bees, causing them to lose their sense of orientation and unable to return to their colony, which causes their death in the field. Hence the recommendation to control and legislate the use of this type of insecticide in Mexico, as has been done in other countries, to protect bees and thereby ensure the production of food for the benefit of humanity.El papel de las abejas en los agroecosistemas es sumamente importante debido a que actúan como agentes polinizadores naturales tanto de los cultivos de importancia económica como de las plantas silvestres; con lo cual se garantiza la producción de alimentos y la conservación de la biodiversidad. Aparte, la apicultura representa uno de los sectores que obtiene más ingresos económicos por concepto de venta y exportación de miel. Sin embargo, este sector tiene múltiples problemas en su sistema de producción, plagas y enfermedades que los han afectado y ha provocado bajas en el número de colonias y una disminución en la producción de miel. Aunado a esto, en los últimos años se ha presentado una desaparición espontanea de las abejas, sin que se le haya podido dar una explicación convincente; a este fenómeno se le conoce como desorden del colapso de las colonias o CCD por sus siglas en ingles. Uno de los factores que afectan y que provocan el colapso de las colonias son el uso de los agroquímicos, principalmente los insecticidas del grupo de los neonicotinoides. Estos insecticidas son derivados de la nicotina y al ser aplicados para controlar las plagas de los cultivos también afectan al sistema nervioso de las abejas, provocando que pierdan el sentido de orientación y que no puedan regresar a su colonia, lo que provoca su muerte en el campo. De aquí la recomendación de controlar y legislar el uso de este tipo de insecticidas en México, como se ha hecho en otros países, para proteger a las abejas y con ello garantizar la producción de alimentos en beneficio de la humanidad

Canagliflozin and renal outcomes in type 2 diabetes and nephropathy

BACKGROUND Type 2 diabetes mellitus is the leading cause of kidney failure worldwide, but few effective long-term treatments are available. In cardiovascular trials of inhibitors of sodium–glucose cotransporter 2 (SGLT2), exploratory results have suggested that such drugs may improve renal outcomes in patients with type 2 diabetes. METHODS In this double-blind, randomized trial, we assigned patients with type 2 diabetes and albuminuric chronic kidney disease to receive canagliflozin, an oral SGLT2 inhibitor, at a dose of 100 mg daily or placebo. All the patients had an estimated glomerular filtration rate (GFR) of 30 to <90 ml per minute per 1.73 m2 of body-surface area and albuminuria (ratio of albumin [mg] to creatinine [g], >300 to 5000) and were treated with renin–angiotensin system blockade. The primary outcome was a composite of end-stage kidney disease (dialysis, transplantation, or a sustained estimated GFR of <15 ml per minute per 1.73 m2), a doubling of the serum creatinine level, or death from renal or cardiovascular causes. Prespecified secondary outcomes were tested hierarchically. RESULTS The trial was stopped early after a planned interim analysis on the recommendation of the data and safety monitoring committee. At that time, 4401 patients had undergone randomization, with a median follow-up of 2.62 years. The relative risk of the primary outcome was 30% lower in the canagliflozin group than in the placebo group, with event rates of 43.2 and 61.2 per 1000 patient-years, respectively (hazard ratio, 0.70; 95% confidence interval [CI], 0.59 to 0.82; P=0.00001). The relative risk of the renal-specific composite of end-stage kidney disease, a doubling of the creatinine level, or death from renal causes was lower by 34% (hazard ratio, 0.66; 95% CI, 0.53 to 0.81; P<0.001), and the relative risk of end-stage kidney disease was lower by 32% (hazard ratio, 0.68; 95% CI, 0.54 to 0.86; P=0.002). The canagliflozin group also had a lower risk of cardiovascular death, myocardial infarction, or stroke (hazard ratio, 0.80; 95% CI, 0.67 to 0.95; P=0.01) and hospitalization for heart failure (hazard ratio, 0.61; 95% CI, 0.47 to 0.80; P<0.001). There were no significant differences in rates of amputation or fracture. CONCLUSIONS In patients with type 2 diabetes and kidney disease, the risk of kidney failure and cardiovascular events was lower in the canagliflozin group than in the placebo group at a median follow-up of 2.62 years

The Combined Effects of Varroa destructor Parasitism and Exposure to Neonicotinoids Affects Honey Bee (Apis mellifera L.) Memory and Gene Expression

Honey bees (Apis mellifera L.) are exposed biotic and abiotic stressors but little is known about their combined effect and impact on neural processes such as learning and memory, which could affect behaviours that are important for individual and colony survival. This study measured memory with the proboscis extension response (PER) assay as well as the expression of neural genes in bees chronically exposed to three different sublethal doses of the insecticide clothianidin and/or the parasitic mite Varroa destructor. The proportion of bees that positively responded to PER at 24 and 48 h post-training (hpt) was significantly reduced when exposed to clothianidin. V. destructor parasitism reduced the proportion of bees that responded to PER at 48 hpt. Combined effects between the lowest clothianidin dose and V. destructor for the proportion of bees that responded to PER were found at 24 hpt. Clothianidin, V. destructor and their combination differentially affected the expression of the neural-related genes, AmNrx-1 (neurexin), AmNlg-1 (neuroligin), and AmAChE-2 (acetylcholinesterase). Different doses of clothianidin down-regulated or up-regulated the genes, whereas V. destructor tended to have a down-regulatory effect. It appears that clothianidin and V. destructor affected neural processes in honey bees through different mechanisms

Effect of Immune Inducers on Nosema ceranae Multiplication and Their Impact on Honey Bee (Apis mellifera L.) Survivorship and Behaviors

Nosema disease is a major disease of honey bees caused by two species of microsporidia, Nosema apis and N. ceranae. Current control involves using antibiotics, which is undesirable because of possible antibiotic resistance and contamination. In this study, flagellin, zymosan, chitosan, and peptidoglycan were investigated as alternatives for controlling N. ceranae infections and for their effect on bee survivorship and behaviors. Chitosan and peptidoglycan significantly reduced the infection, and significantly increased survivorship of infected bees, with chitosan being more effective. However, neither compound altered the bees’ hygienic behavior, which was also not affected by the infection. Chitosan significantly increased pollen foraging and both compounds significantly increased non-pollen foraging compared to healthy and infected bees. Memory retention, evaluated with the proboscis extension reflex assay, was temporarily impaired by chitosan but was not affected by peptidoglycan, nor was it affected by N. ceranae infection compared to the non-infected bees. This study indicates that chitosan and peptidoglycan provide benefits by partially reducing N. ceranae spore numbers while increasing survivorship compared to N. ceranae infected bees. Also, chitosan and peptidoglycan improved aspects of foraging behavior even more than in healthy bees, showing that they may act as stimulators of important honey bee behaviors

Interaction of field realistic doses of clothianidin and Varroa destructor parasitism on adult honey bee (Apis mellifera L.) health and neural gene expression, and antagonistic effects on differentially expressed genes.

While many studies have examined the effects of neonicotinoid insecticides and the parasitic mite Varroa destructor on honey bees (Apis mellifera), more information on the combined effects of such stressors on gene expression, including neural related genes, and their impact on biological pathways is needed. This study analyzed the effects of field realistic concentrations of the neonicotinoid clothianidin on adult bees infested and not infested with V. destructor over 21 consecutive days and then determined bee survivorship, weight, deformed wing virus (DWV) levels and gene expression. V. destructor parasitism with or without clothianidin exposure was significantly associated with decreased survivorship, weight loss and higher DWV levels, while clothianidin exposure was only associated with higher levels of DWV. Expression analysis of the neural genes AmNlg-1, BlCh and AmAChE-2 showed that V. destructor caused a significant down-regulation of all of them, whereas clothianidin caused a significant down-regulation of only AmNrx-1 and BlCh. An interaction was only detected for AmNrx-1 expression. RNAseq analysis showed that clothianidin exposure resulted in 6.5 times more up-regulated differentially expressed genes (DEGs) than V. destructor alone and 123 times more than clothianidin combined with V. destructor. Similar results were obtained with down-regulated DEGs, except for a higher number of DEGs shared between V. destructor and the combined stressors. KEGG (Kyoto Encyclopedia of Genes and Genomes) biological pathway analysis of the DEGs showed that the stressor linked to the highest number of KEGG pathways was clothianidin, followed by V. destructor, and then considerably fewer number of KEGG pathways with the combined stressors. The reduced numbers of DEGs and KEGG pathways associated with the DEGs for the combined stressors compared to the stressors alone indicates that the interaction of the stressors is not additive or synergistic, but antagonistic. The possible implications of the antagonistic effect on the number of DEGs are discussed

A mathematical model for the interplay of Nosema infection and forager losses in honey bee colonies

We present a mathematical model (a) for the infection of a honey bee colony with Nosema ceranae. This is a system of five ordinary differential equations for the dependent variables healthy and infected worker bees in the hive, healthy and infected forager bees, and disease potential deposited in the hive. The model is then (b) extended to account for increased forager losses, e.g. caused by exposure to external stressors. The model is non-autonomous with periodic coefficient functions. Algebraic complexity prevents a rigorous mathematical analysis. Therefore, we resort to computer simulations in addition to some analytical results in the constant coefficient case. We investigate each of the two stressors (a) and (b) individually and jointly. Our results indicate that the combined effect of two stressors, both of which can be tolerated by the colony individually, might lead to colony failure, suggesting multi-factorial causes behind losses of honey bee colonies

of African and European descent

Genotype and task influence stinging response thresholds of honeybee (Apis mellifera L.) worker