Rhythmic 24 h Variation of Core Body Temperature and Locomotor Activity in a Subterranean Rodent (Ctenomys aff. knighti), the Tuco-Tuco

The tuco-tuco Ctenomys aff. knighti is a subterranean rodent which inhabits a semi-arid area in Northwestern Argentina. Although they live in underground burrows where environmental cycles are attenuated, they display robust, 24 h locomotor activity rhythms that are synchronized by light/dark cycles, both in laboratory and field conditions. The underground environment also poses energetic challenges (e.g. high-energy demands of digging, hypoxia, high humidity, low food availability) that have motivated thermoregulation studies in several subterranean rodent species. By using chronobiological protocols, the present work aims to contribute towards these studies by exploring day-night variations of thermoregulatory functions in tuco-tucos, starting with body temperature and its temporal relationship to locomotor activity. Animals showed daily, 24 h body temperature rhythms that persisted even in constant darkness and temperature, synchronizing to a daily light/dark cycle, with highest values occurring during darkness hours. The range of oscillation of body temperature was slightly lower than those reported for similar-sized and dark-active rodents. Most rhythmic parameters, such as period and phase, did not change upon removal of the running wheel. Body temperature and locomotor activity rhythms were robustly associated in time. The former persisted even after removal of the acute effects of intense activity on body temperature by a statistical method. Finally, regression gradients between body temperature and activity were higher in the beginning of the night, suggesting day-night variation in thermal conductance and heat production. Consideration of these day-night variations in thermoregulatory processes is beneficial for further studies on thermoregulation and energetics of subterranean rodents.     

High water flow velocity reduces beta diversity and leads to a distinct composition of Oligochaeta in Neotropical lotic ecosystems

Limnology - Water flow velocity is a strong environmental filter structuring benthic communities in lotic ecosystems. While many studies have determined its effect on the distribution and diversity...     

Effects of novel acylhydrazones derived from 4-quinolone on the acetylcholinesterase activity and Aβ42 peptide fibrils formation

Acetylcholinesterase inhibitors and compounds that trigger Aβ amyloid oligomerization and fibrillization represent an opportunity to discover new drug candidates to treat Alzheimer’s disease. In this work, we synthesized nine new acylhydrazones and a known one, both employing 3-carboethoxy-4-quinolone derivatives as starting materials with chemical yields ranging from 63% to 90%. We evaluated the effect of these compounds on the acetylcholinesterase (AChE) activity and the fibrillization of Aβ₄₂ peptide. Except for one acylhydrazone, the compounds exhibited good inhibitory effect on AChE (1.2?μM?<?IC₅₀ values?<?17?μM). They also showed a significant decrease in the thioflavin-T fluorescence emission, suggesting an inhibitory effect on the Aβ₄₂ fibril formation.     

Development and Evaluation of Sustained-Release Etoposide-Loaded Poly(ε-Caprolactone) Implants

Poly(ε-caprolactone) implants containing etoposide, an important chemotherapeutic agent and topoisomerase II inhibitor, were fabricated by a melt method and characterized in terms of content uniformity, morphology, drug physical state, and sterility. In vitro and in vivo drug release from the implants was also evaluated. The cytotoxic activity of implants against HeLa cells was studied. The short-term tolerance of the implants was investigated after subcutaneous implantation in mice. The original chemical structure of etoposide was preserved after incorporation into the polymeric matrix, in which the drug was dispersed uniformly. Etoposide was present in crystalline form in the polymeric implant. In vitro release study showed prolonged and controlled release of etoposide, which showed cytotoxicity activity against HeLa cells. After implantation, good correlation between in vitro and in vivo drug release was found. The implants demonstrated good short-term tolerance in mice. These results tend to show that etoposide-loaded implants could be potentially applied as a local etoposide delivery system.     

Selective serotonin reuptake inhibitors,and serotonin and norepinephrine reuptake inhibitors for anxiety,obsessive-compulsive,and stress disorders: A 3-level network meta-analysis

BackgroundAnxiety, obsessive-compulsive, and stress-related disorders frequently co-occur, and patients often present symptoms of several domains. Treatment involves the use of selective serotonin reuptake inhibitors (SSRIs) and serotonin and norepinephrine reuptake inhibitors (SNRIs), but data on comparative efficacy and acceptability are lacking. We aimed to compare the efficacy of SSRIs, SNRIs, and placebo in multiple symptom domains in patients with these diagnoses over the lifespan through a 3-level network meta-analysis.Methods and findingsWe searched for published and unpublished randomized controlled trials that aimed to assess the efficacy of SSRIs or SNRIs in participants (adults and children) with diagnosis of any anxiety, obsessive-compulsive, or stress-related disorder in MEDLINE, PsycINFO, Embase, and Cochrane Library from inception to 23 April 2015, with an update on 11 November 2020. We supplemented electronic database searches with manual searches for published and unpublished randomized controlled trials registered in publicly accessible clinical trial registries and pharmaceutical companies’ databases. No restriction was made regarding comorbidities with any other mental disorder, participants’ age and sex, blinding of participants and researchers, date of publication, or study language. The primary outcome was the aggregate measure of internalizing symptoms of these disorders. Secondary outcomes included specific symptom domains and treatment discontinuation rate. We estimated standardized mean differences (SMDs) with 3-level network meta-analysis with random slopes by study for medication and assessment instrument. Risk of bias appraisal was performed using the Cochrane Collaboration’s risk of bias tool. This study was registered in PROSPERO (CRD42017069090). We analyzed 469 outcome measures from 135 studies (n = 30,245). All medications were more effective than placebo for the aggregate measure of internalizing symptoms (SMD −0.56, 95% CI −0.62 to −0.51, p < 0.001), for all symptom domains, and in patients from all diagnostic categories. We also found significant results when restricting to the most used assessment instrument for each diagnosis; nevertheless, this restriction led to exclusion of 72.71% of outcome measures. Pairwise comparisons revealed only small differences between medications in efficacy and acceptability. Limitations include the moderate heterogeneity found in most outcomes and the moderate risk of bias identified in most of the trials.ConclusionsIn this study, we observed that all SSRIs and SNRIs were effective for multiple symptom domains, and in patients from all included diagnostic categories. We found minimal differences between medications concerning efficacy and acceptability. This three-level network meta-analysis contributes to an ongoing discussion about the true benefit of antidepressants with robust evidence, considering the significantly larger quantity of data and higher statistical power when compared to previous studies. The 3-level approach allowed us to properly assess the efficacy of these medications on internalizing psychopathology, avoiding potential biases related to the exclusion of information due to distinct assessment instruments, and to explore the multilevel structure of transdiagnostic efficacy.

In a meta-analysis of randomized trials, Natan Pereira Gosmann and colleagues study efficacy of SSRIs and SNRIs for symptoms of anxiety, obsessive-compulsive, and stress-related disorders.     

Comparison between two cryopreservation techniques of human ovarian cortex: morphological aspects and the heat shock response (HSR)

This study was tailored to compare the cryopreservation of the human ovarian cortex using closed metal container vitrification or the slow-freezing technique. Superficial ovarian cortical tissue biopsies were collected from 12 participants who underwent gynaecological videolaparoscopy. The fragmented samples were allocated to three experimental conditions: (a) fresh ovarian tissue, (b) slow-freezing, and (c) vitrification with a metal closed container. After thawing or rewarming, cellular morphological analyses were performed to determine tissue viability. The cellular response to thermal stress was measured by a putative increase in the immune quantification of the heat shock protein 70 kDa (heat shock protein 70 kDa response — HSR) after a heat challenge (2 h exposure at 42 °C). Both the total number of intact follicles and the frequency of primordial follicles were higher in fresh ovarian tissue than in the preserved samples, regardless of the technique employed. There was a trend towards an increase in the absolute number of intact follicles in the tissue preserved by vitrification. After cryopreservation, a higher HSR was obtained after slow-freezing. These results indicate that both cryopreservation techniques present advantages and may be used as alternatives to ovarian tissue cryopreservation.