Evolutionary history of regeneration in crinoids (Echinodermata)

The fossil record indicates that crinoids have exhibited remarkable regenerative abilities since their origin in the Ordovician, abilities that they likely inherited from stem-group echinoderms. Regeneration in extant and fossil crinoids is recognized by abrupt differences in the size of abutting plates, aberrant branching patterns, and discontinuities in carbon isotopes. While recovery is common, not all lost body parts can be regenerated; filling plates and overgrowths are evidence of non-regenerative healing. Considering them as a whole, Paleozoic crinoids exhibit the same range of regenerative and non-regenerative healing as Recent crinoids. For example, Paleozoic and extant crinoids show evidence of crown regeneration and stalk regrowth, which can occur only if the entoneural nerve center (chambered organ) remains intact. One group of Paleozoic crinoids, the camerates, may be an exception in that they probably could not regenerate their complex calyx-plating arrangements, including arm facets, but their calyxes could be healed with reparative plates. With that exception, and despite evidence for increases in predation pressure, there is no compelling evidence that crinoids have changed though time in their ability to recover from wounds. Finally, although crinoid appendages may be lost as a consequence of severe abiotic stress and through ontogenetic development, spatiotemporal changes in the intensity and frequency of biotic interactions, especially direct attacks, are the most likely explanation for observed patterns of regeneration and autotomy in crinoids.     

The antiestrogen ICI 182,780 decreases the expression of estrogen receptor-alpha but has no effect on estrogen receptor-beta and androgen receptor in rat efferent ductules

Background  

The antiestrogen ICI 182,780 has been used successfully as an alternative experimental model for the study of estrogen action in the rodent adult male reproductive tract. Although ICI 182,780 causes severe alterations in testicular and efferent ductule morphology and function, the effects on the expression of estrogen and androgen receptors in the male have not been shown.     

Clinical data analysis of telmisartan for hypertension management in Indian population

It is of interest to evaluate the clinical characteristics, treatment patterns, clinical effectiveness, and safety of telmisartan as a monotherapy or as part of combination therapy in Indian adults (>18 years old) with hypertension. All patients were receiving telmisartan as monotherapy, or as a combination therapy for hypertension management. Demographics, risk factors, existing comorbidity, and ongoing medical therapies were retrieved from the patients’ medical records. A total of 8607 patients with hypertension (median age, 51.0 years) were part of the study. The gender distribution suggested, 5534(64.3%) patients were male, and 3073 (35.7%) were female patients. The excess salt intake (39.0%) was the most common risk factor according to the results. The analysis revealed telmisartan dual therapy (57.9%) as the most prescribed therapy, followed by monotherapy (32.5%), and triple therapy (9.6%). Further, telmisartan 40mg (21.3%) and telmisartan 40mg plus amlodipine 5mg (17.6%) were the most commonly prescribed therapies. The data suggested that only 17.2% of patients required dose titration. The mean systolic blood pressure (SBP) and diastolic blood pressure (DBP) (mmHg) were significantly decreased with monotherapy (mean change: 19.8 [15.1] mmHg and 8.8[8.2] mmHg), dual therapy (mean change: 23.7 [16.6] mmHg and 10.3[8.5] mmHg), and triple therapy (mean change: 28.6 [19.0] mmHg and 12.1[10.8] mmHg) after the treatment (P<0.001). A total of 98.4% of the patients were compliant, and 97.6% achieved the target blood pressure goal with telmisartan-based therapy. There were 157 adverse events reported altogether. The Physicians'' global evaluation of efficacy and tolerability showed the majority of the patients receiving telmisartan-based therapy on a good to excellent scale. Telmisartan used as a monotherapeutic agent or as a part of combination therapy was successful and effective in reducing blood pressure and achieving the blood pressure target. Irrespective of the patient’s age, duration, and stages of hypertension, the study resulted in a good to excellent scale in efficacy and tolerability in the Indian patients having hypertension.     

Using platyceratid gastropod behaviour to test functional morphology

During the Mississippian (Tournaisian), numerous crinoid genera of the subclass Camerata evolved exaggerated anal tubes, cylindrical extensions of the tegmen with the anus at the distal end. Additionally, camerates exhibit higher frequency of platyceratid gastropod infestation than any other crinoid clade leading some researchers to speculate that anal tubes evolved in response to platyceratid parasitism. To test the infestation avoidance role of anal tubes, platyceratid distribution was analyzed among 636 tubed and 675 tubeless crinoids from Mississippian strata in North America. Results demonstrate significantly higher infestation frequency in tubeless crinoids. Rather than attach to the anal vent, as is typical for platyceratids, the gastropods that infested tubed crinoids are always found at the tube base and acquired nutrients from their hosts via drilling. It is likely that infesting tubeless crinoids was a more cost effective trophic strategy than drilling tubed crinoids.     

Drilling under threat: An experimental assessment of the drilling behavior of Nucella lamellosa in the presence of a predator

Using the drilling muricid, Nucella lamellosa (Gmelin 1791) and its prey, the mussel Mytilus trossulus (Gould 1850), the impact of a secondary predator, the crab Cancer gracilis, on drilling was investigated experimentally. The frequency of incomplete holes was compared under two conditions: (1) when the gastropod's natural predator, C. gracilis, was present and (2) when it was absent. The results indicate that the presence of a secondary predator can affect drilling activity, leading to a significant increase in the frequency of incomplete drill holes. The introduction of a secondary predator can also decrease the overall drilling frequency. The size distributions of completely and incompletely drilled mussels suggest that in the presence of the secondary predator the decision by the gastropod to either abandon or continue drilling its prey might be influenced by how much time it has already invested into drilling or the size of the prey item. These results are important for the ecological and evolutionary implications of incomplete drill holes frequencies, especially with regard for their use as proxies for evolutionary prey improvement.