Compounds from multilayer plastic bags cause reproductive failures in artificial insemination

High levels of reproductive failure were detected in some Spanish sow farms in the Spring of 2010. Regular returns to estrus and variable reductions in litter size were observed. The problem started suddenly and did not appear to be related to the quality of the ejaculates, disease, alterations of body condition or any other apparent reasons. Subsequent studies determined that the problem was the origin of the plastic bags used for semen storage. Chemical analysis of the suspicious bags identified unexpected compounds such as BADGE, a cyclic lactone and an unknown phthalate that leached into the semen at concentrations of 0.2 to 2.5 mg/L. Spermatozoa preserved in these bags passed all of the routine quality control tests, and no differences were observed between storage in the control and suspicious bags (p > 0.05). In vitro fecundation tests and endocrine profiler panel analysis (EPP) did not show any alterations, whereas the in vivo tests confirmed the described failure. This is the first described relationship between reproductive failure and toxic compounds released from plastic bags.

Muscarinic toxins: novel pharmacological tools for the muscarinic cholinergic system

Muscarinic receptors are widely spread throughout the body, and are involved in the regulation of fundamental physiological processes, like the modulation of the heart rate, control of motor systems and modulation of learning and memory. In the central nervous system the cholinergic transmission is mainly mediated by muscarinic receptors; there are five subtypes that are all expressed in the brain of mammals (m1-m5). There are regional differences in their concentrations in the brain and more than one subtype is expressed in the same cell. It has been difficult to study their localization and function in vivo due to the lack of ligands that exclusively act on one subtype of the receptor. We studied the action of the muscarinic toxins MT1, MT2 and MT3, from the venom of the snake Dendroaspis angusticeps, on muscarinic receptors, by using the classical muscarinic radioligand 3H-NMS as reporter of the inhibition of its own binding, to either native or cloned receptors. We have also studied the in vivo effects on memory retention of the injection of the toxins into discrete brain regions. The muscarinic toxins appear to be invaluable tools to study receptor pharmacology, physiology and structure/function relationships. They would enable the design of new, more selective, pharmacological agents.

Muscarinic toxin selective for m4 receptors impairs memory in the rat

The selectivity of the muscarinic toxin MT3 from green mamba snake venom was corroborated by inhibition of the binding of [3H]NMS, a classical muscarinic radioligand, to native and cloned muscarinic receptors, showing 214-fold higher affinity for m4 than for m1 subtype, without significant binding to the others. The highest concentrations of MT3 sites (putative m4 receptors) in the rat brain were found in striatum and olfactory tubercle, intermediate concentration in dentate gyrus and CA1, and lower but still conspicuous levels in CA3 and frontal cortex. MT3 caused retrograde amnesia of an inhibitory avoidance task, when injected into the dorsal hippocampus of rats after training, suggesting a positive role of these MT3 sensitive sites, which are probably m4 muscarinic receptors, in memory consolidation of this task.

Radiotherapy compared to chemotherapy as initial treatment of angiocentric centrofacial lymphoma (polymorphic reticulosis)

Polymorphic reticulosis has recently been characterized as an angiocentric lymphoproliferative disorder of the peripheral T-lymphocytes. However, its treatment is still a matter of controversy. In order to study efficacy and toxicity of the primary treatment, we reviewed clinical features and therapeutic results in 29 patients seen at the Instituto Nacional de Cancerologia de Mexico. Nineteen patients received primary local irradiation and 10 patients primary combination chemotherapy. In the radiotherapy group, 14 (74%) patients achieved complete response, but only 4 (40%) did so in the primary chemotherapy group. Five patients in the latter group died of treatment-related complications. The 5-year actuarial survival rate was 70% in the irradiation group, while the 1-year survival rate was only 15% in the chemotherapy group. These data strongly suggest that, in polymorphic reticulosis, initial chemotherapy may be very toxic.

[Occlusion distribution in a 7- to 14-year old student population]

The epidemiological characterization of the occlusion was made on basis of the classical Angle Classification through a statistical selection from a total of 4363 females and males children; which ages ranged between 7 to 14 years old. These were students registered in public federal schools located in the south of the metropolitan area. The results of the study were determined as follows: Class I, 84.7%; Class II, 10.9%, Class III 4.3%.

Hyperbilirubinemia after single-stage radical cystectomy and ileal loop diversion

One hundred ninety-two patients underwent single-stage radical cystectomy and ileal loop diversion over a three-year period. Postoperative hyperbilirubinemia occurred in 21 patients (10.9%) within the first ten days. Early hyperbilirubinemia occurred in 11 patients by postoperative day 5, accounting for 52 percent of the hyperbilirubinemic patients and 5.7 percent of the study population. Elevation persisted into the six to ten-day postoperative period for 9 at which time a total of 18 patients had bilirubin levels elevated above their presurgical values (P less than 0.001). This clinical observation appears to be benign and worthy of further investigation.