Potential Role of Transient Receptor Potential Channel M5 in Sensing Putative Pheromones in Mouse Olfactory Sensory Neurons

Based on pharmacological studies of chemosensory transduction in transient receptor potential channel M5 (TRPM5) knockout mice it was hypothesized that this channel is involved in transduction for a subset of putative pheromones in mouse olfactory sensory neurons (OSNs). Yet, in the same study an electroolfactogram (EOG) in the mouse olfactory epithelium showed no significant difference in the responses to pheromones (and odors) between wild type and TRPM5 knockout mice. Here we show that the number of OSNs expressing TRPM5 is increased by unilateral naris occlusion. Importantly, EOG experiments show that mice lacking TRPM5 show a decreased response in the occluded epithelia to putative pheromones as opposed to wild type mice that show no change upon unilateral naris occlusion. This evidence indicates that under decreased olfactory sensory input TRPM5 plays a role in mediating putative pheromone transduction. Furthermore, we demonstrate that cyclic nucleotide gated channel A2 knockout (CNGA2-KO) mice that show substantially decreased or absent responses to odors and pheromones also have elevated levels of TRPM5 compared to wild type mice. Taken together, our evidence suggests that TRPM5 plays a role in mediating transduction for putative pheromones under conditions of reduced chemosensory input

A Comparison of Osteoclast-Rich and Osteoclast-Poor Osteopetrosis in Adult Mice Sheds Light on the Role of the Osteoclast in Coupling Bone Resorption and Bone Formation

Osteopetrosis due to lack of acid secretion by osteoclasts is characterized by abolished bone resorption, increased osteoclast numbers, but normal or even increased bone formation. In contrast, osteoclast-poor osteopetrosis appears to have less osteoblasts and reduced bone formation, indicating that osteoclasts are important for regulating osteoblast activity. To illuminate the role of the osteoclast in controlling bone remodeling, we transplanted irradiated skeletally mature 3-month old wild-type mice with hematopoietic stem cells (HSCs) to generate either an osteoclast-rich or osteoclast-poor adult osteopetrosis model. We used fetal liver HSCs from (1) oc/oc mice, (2) RANK KO mice, and (3) compared these to wt control cells. TRAP5b activity, a marker of osteoclast number and size, was increased in the oc/oc recipients, while a significant reduction was seen in the RANK KO recipients. In contrast, the bone resorption marker CTX-I was similarly decreased in both groups. Both oc/oc and Rank KO recipients developed a mild osteopetrotic phenotype. However, the osteoclast-rich oc/oc recipients showed higher trabecular bone volume (40 %), increased bone strength (66 %), and increased bone formation rate (54 %) in trabecular bone, while RANK KO recipients showed only minor trends compared to control recipients. We here show that maintaining non-resorbing osteoclasts, as opposed to reducing the osteoclasts, leads to increased bone formation, bone volume, and ultimately higher bone strength in vivo, which indicates that osteoclasts are sources of anabolic molecules for the osteoblasts

Clinical outcomes of patients with lumbar disc herniation, selected for one-level open-discectomy and microdiscectomy

The aim of our study was twofold: firstly, to compare the preoperative and postoperative results at mid-term follow-up periods along with the data of the control group. Secondly, to evaluate the effectiveness among open-discectomy and microdiscectomy surgical groups. In the present study, we investigated a cohort of 100 patients with the lumbar disc herniation causing low back pain compared to 100 subjects of the control group with the non-specific low back pain by applying physical activity, pain scale, Short Form 36 General Health Questionnaire and additional postoperative records of patient’s satisfaction and complications level, consumption of analgesics, and return to work status. The quantitative analysis of all questionnaires showed substantial differences in the preoperative and postoperative groups. The best results were achieved at the second year follow-up period. However, there were no statistically significant differences in both the examined surgical subgroups (p > 0.05). In addition, we estimated from moderate to great statistical significance (p < 0.01–0.05) among preoperative and overall postoperative results: PHC and MHC in the SF-36, Oswestry and VAS. The total increased satisfaction, reherniation rate and return to work frequency comprised 40, 9 and 64%, respectively. The analgesics were still indicated for 21% of the patients. The results of the present study suggest of sufficient decompression in both surgical groups, as the health-related quality of life parameters (Oswestry, VAS and SF-36) were defined as clinically improved. Regardless of persisted minor pain in both areas, it remained greater in the low back than in the leg, which should be held for beneficial to decompressive surgery

Costly Signaling Theory in Archaeology

Why do people engage in seemingly wasteful behaviors and invest in extravagant material displays? Since its introduction into anthropological archaeology two decades ago, costly signaling theory (CST) has been used to provide an answer to this question. With broad origins in biology and social theory, costly signaling theory seeks to provide an evolutionary explanation for why humans engage in seemingly wasteful behaviors. In this chapter, I take stock of costly signaling theory in archaeology by (1) tracing its theoretical origins and history of adoption into anthropological archaeology, (2) highlighting key issues that archaeologists have been wrestling with in order to make CST applicable to the past, (3) discussing the breadth of uses of CST in the recent archaeological literature, and (4) presenting an analytical framework that can make CST more rigorous and in the future. Despite persistent doubts about the explanatory utility of CST, the study of signaling from an evolutionary perspective remains a key aspect of evolutionary archaeology