AMPKα1 negatively regulates osteoclastogenesis and mitigates pathological bone loss.

Osteoclasts are specialized cells responsible for bone resorption, a highly energy-demanding process. Focus on osteoclast metabolism could be a key for the treatment of osteolytic diseases including osteoporosis. In this context, AMP-activated protein kinase α1 (AMPKα1), an energy sensor highly expressed in osteoclasts, participates in the metabolic reconfiguration during osteoclast differentiation and activation. This study aimed to elucidate the role of AMPKα1 during osteoclastogenesis in vitro and its impact in bone loss in vivo. Using LysMcre/0AMPK⍺1f/f animals and LysMcre/0 as control, we evaluated how AMPKα1 interferes with osteoclastogenesis and bone resorption activity in vitro. We found that AMPKα1 is highly expressed in the early stages of osteoclastogenesis. Genetic deletion of AMPKα1 leads to increased gene expression of osteoclast differentiation and fusion markers. In addition, LysMcre/0AMPK⍺1f/f mice had an increased number and size of differentiated osteoclast. Accordingly, AMPKα1 negatively regulates bone resorption in vitro, as evidenced by the area of bone resorption in LysMcre/0AMPK⍺1f/f osteoclasts. Our data further demonstrated that AMPKα1 regulates mitochondrial fusion and fission markers upregulating Mfn2 and downregulating DRP1 (dynamics-related protein 1) and that Ctskcre/0AMPK⍺1f/f osteoclasts lead to an increase in the number of mitochondria in AMPK⍺1-deficient osteoclast. In our in vivo study, femurs from Ctskcre/0AMPK⍺1f/f animals exhibited bone loss associated with the increased number of osteoclasts, and there was no difference between Sham and ovariectomized group. Our data suggest that AMPKα1 acts as a negative regulator of osteoclastogenesis, and the depletion of AMPKα1 in osteoclast leads to a bone loss state similar to that observed after ovariectomy.

Epstein-Barr virus nuclear antigen 2 extensively rewires the human chromatin landscape at autoimmune risk loci.

The interplay between environmental and genetic factors plays a key role in the development of many autoimmune diseases. In particular, the Epstein-Barr virus (EBV) is an established contributor to multiple sclerosis, lupus, and other disorders. Previously, we showed that the EBV nuclear antigen 2 (EBNA2) transactivating protein occupies up to half of the risk loci for a set of seven autoimmune disorders. To further examine the mechanistic roles played by EBNA2 at these loci on a genome-wide scale, we globally examined gene expression, chromatin accessibility, chromatin looping, and EBNA2 binding in a B cell line that was (1) uninfected, (2) infected with a strain of EBV lacking EBNA2, or (3) infected with a strain that expresses EBNA2. We identified more than 400 EBNA2-dependent differentially expressed human genes and more than 5000 EBNA2 binding events in the human genome. ATAC-seq analysis revealed more than 2000 regions in the human genome with EBNA2-dependent chromatin accessibility, and HiChIP data revealed more than 1700 regions where EBNA2 altered chromatin looping interactions. Autoimmune genetic risk loci were highly enriched at the sites of these EBNA2-dependent chromatin-altering events. We present examples of autoimmune risk genotype-dependent EBNA2 events, nominating genetic risk mechanisms for autoimmune risk loci such as ZMIZ1 Taken together, our results reveal important interactions between host genetic variation and EBNA2-driven disease mechanisms. Further, our study highlights a critical role for EBNA2 in rewiring human gene regulatory programs through rearrangement of the chromatin landscape and nominates these interactions as components of genetic mechanisms that influence the risk of multiple autoimmune diseases.

An ongoing science-society-ethics experiment: The human challenge trial debate in COVID-19 pandemic: The human challenge trial debate in COVID-19 pandemic.

Human challenge trials to deliberately infect volunteers with SARS-CoV-2 should inspire wider debates about research ethics and participants' motivations to take part in such studies.

Intraoperative thermal mapping of mammary tumors in dogs.

In this study, videothermometry's application in detecting mammary tumors in dogs is explored in-depth. The research hypothesizes that this technique can effectively identify cancerous tissues during surgery by analyzing thermal patterns. The methodology involved comparing thermal imaging results from dogs with palpable mammary nodules against a control group, focusing on capturing real-time thermal patterns. Results were significant, showing distinct thermal patterns in carcinomas. This indicates videothermometry's capability in accurately identifying micro metastases and differentiating between neoplastic and non-neoplastic changes. The study concludes that videothermometry has considerable potential in enhancing surgical precision, especially in tumor resection and safety margin definition, but emphasizes the need for further research to thoroughly understand the thermal signatures of various mammary tumors in dogs.

Hybridization in late stages of speciation: Strong but incomplete genome-wide reproductive isolation and 'large Z-effect' in a moving hybrid zone.

In organisms reproducing sexually, speciation occurs when increasing divergence results in pre- or post-zygotic reproductive isolation between lineages. Studies focusing on reproductive isolation origin in early stages of speciation are common and many rely on genomic scans to infer introgression providing limited information on the genomic architecture of reproductive isolation long-term maintenance. This study analyses a natural hybrid zone between two species in a late stage of speciation. We used ddRADseq genotyping in the contact between Podarcis bocagei and P. carbonelli to examine admixture extent, analyse hybrid zone stability and assess genome-wide variation in selection against introgression. We confirmed strong but incomplete reproductive isolation in a bimodal hybrid zone. New findings revealed population genetic structure within P. carbonelli in the contact zone; geographical and genomic clines analysis suggested strong selection against gene flow, but a relatively small proportion of the loci can introgress, mostly within the narrow contact zone. However, geographical clines revealed that a few introgressed loci show signs of potential positive selection, particularly into P. bocagei. Geographical clines also detected a signal of hybrid zone movement towards P. bocagei distribution. Genomic cline analysis revealed heterogeneous patterns of introgression among loci within the syntopy zone, but the majority maintain a strong association with the genomic background of origin. However, incongruences between both cline approaches were found, potentially driven by confounding effects on genomic clines. Last, an important role of the Z chromosome in reproductive isolation is suggested. Importantly, overall patterns of restricted introgression seem to result from numerous strong intrinsic barriers across the genome.

Retractions and Rewards in Science: An Open Question for Reviewers and Funders.

In recent years, the changing landscape for the conduct and assessment of research and of researchers has increased scrutiny of the reward systems of science. In this context, correcting the research record, including retractions, has gained attention and space in the publication system. One question is the possible influence of retractions on the careers of scientists. It might be assessed, for example, through citation patterns or productivity rates for authors who have had one or more retractions. This is an emerging issue today, with growing discussions in the research community about impact. We have explored the influence of retractions on grant review criteria. Here, we present results of a qualitative study exploring the views of a group of six representatives of funding agencies from different countries and of a follow-up survey of 224 reviewers in the US. These reviewers have served on panels for the National Science Foundation, the National Institutes of Health, and/or a few other agencies. We collected their perceptions about the influence of self-correction of the literature and of retractions on grant decisions. Our results suggest that correcting the research record, for honest error or misconduct, is perceived as an important mechanism to strengthen the reliability of science, among most respondents. However, retractions and self-correcting the literature at large are not factors influencing grant review, and dealing with retractions in reviewing grants is an open question for funders.

Atypical cyclins in cancer: New kids on the block?

Atypical cyclins have recently emerged as a new subfamily of cyclins characterized by common structural features and interactor pattern. Interestingly, atypical cyclins are phylogenetically close to canonical cyclins, which have well-established roles in cell cycle regulation and cancer. Therefore, although the function of atypical cyclins is still poorly characterized, it seems likely that they are involved in cancer pathogenesis as well. Here, we coupled gene expression and prognostic significance analysis to bibliographic search in order to provide new insights into the role of atypical cyclins in cancer. The information gathered suggests that atypical cyclins intervene in critical processes to sustain cancer growth and have potential to become novel prognostic markers and drug targets in cancer.

Extended treatment with (1→3)(1→6)-ß-d-glucan (Botryosphaeran) reduces obesity and its comorbidities in high-fat/high-sugar diet-fed rats.

Obesity is associated with other diseases such as diabetes and cancer. Botryosphaeran, a fungal (1→3)(1→6)-ß-d-glucan, is described to present antimutagenic, hypoglycemic, hypocholesterolemic, and antitumor activities when administered by gavage over 15 days in rats and mice. Thus, the present study aims to analyze the metabolic effects of Botryosphaeran (12 mg/kg body weight/day) treatment over 30 days in obese Wistar male rats. Obesity was induced in the rats by a high-fat/high-sugar diet for 8 weeks. Control rats received a standard diet. On the 5th week, Botryosphaeran treatment commenced. Groups: control, obese, and obese+Botryosphaeran 30 days. In the 8th week, obesity was characterized. Feed intake, glucose and lipid profiles, glucose tolerance, and insulin sensitivity were analyzed. Obese rats showed accumulation of visceral adipose tissue, reduction of muscle mass, glucose intolerance, insulin resistance, hyperglycemia, and dyslipidemia. Botryosphaeran effectively reduced weight gains and the accumulation of retroperitoneal adipose tissue, corrected the levels of glucose, triglycerides, and very low-density lipoprotein-cholestrol, and improved insulin sensitivity. Treatment for 30 days was effective in maintaining the beneficial effects demonstrated by this ß-glucan when administered for 15 days without promoting side effects. Treatment with (1→3)(1→6)-ß- d-glucan presented anti-obesogenic and beneficial metabolic effects in Wistar rats; important for the treatment of obesity and its comorbidities.

Toward understanding cancer stem cell heterogeneity in the tumor microenvironment.

The epithelial-mesenchymal transition (EMT) and cancer stem cell (CSC) formation are two paramount processes driving tumor progression, therapy resistance, and cancer metastasis. Recent experiments show that cells with varying EMT and CSC phenotypes are spatially segregated in the primary tumor. The underlying mechanisms generating such spatiotemporal dynamics in the tumor microenvironment, however, remain largely unexplored. Here, we show through a mechanism-based dynamical model that the diffusion of EMT-inducing signals such as TGF-ß, together with noncell autonomous control of EMT and CSC decision making via the Notch signaling pathway, can explain experimentally observed disparate localization of subsets of CSCs with varying EMT phenotypes in the tumor. Our simulations show that the more mesenchymal CSCs lie at the invasive edge, while the hybrid epithelial/mesenchymal (E/M) CSCs reside in the tumor interior. Further, motivated by the role of Notch-Jagged signaling in mediating EMT and stemness, we investigated the microenvironmental factors that promote Notch-Jagged signaling. We show that many inflammatory cytokines such as IL-6 that can promote Notch-Jagged signaling can (i) stabilize a hybrid E/M phenotype, (ii) increase the likelihood of spatial proximity of hybrid E/M cells, and (iii) expand the fraction of CSCs. To validate the predicted connection between Notch-Jagged signaling and stemness, we knocked down JAG1 in hybrid E/M SUM149 human breast cancer cells in vitro. JAG1 knockdown significantly restricted tumor organoid formation, confirming the key role that Notch-Jagged signaling can play in tumor progression. Together, our integrated computational-experimental framework reveals the underlying principles of spatiotemporal dynamics of EMT and CSCs.

Botryosphaeran Attenuates Tumor Development and the Cancer Cachexia Syndrome in Walker-256 Tumor-Bearing Obese Rats and Improves the Metabolic and Hematological Profiles of These Rats.

Studies demonstrate that obesity can increase tumor development. Botryosphaeran, a fungal (1→3)(1→6)-ß-D-glucan, presents antimutagenic, antiproliferative and pro-apoptotic activities. This study evaluated the effects of botryosphaeran on tumor development and metabolic and hematological parameters in tumor-bearing obese and non-obese rats. Obesity was induced by a high-fat and high-sugar diet, while control rats received standard diet and water without sugar for 10 weeks. On 8th-week, Walker-256 tumor cells were inoculated in the rats, and treatment with botryosphaeran (12 mg/Kg b.w.) started. Groups:control tumor-CT, control tumor botryosphaeran-CTB, obese tumor-OT and obese tumor botryosphaeran-OTB. On 10th-week, tumor development, cachexia, metabolic and hematological parameters were analyzed. Tumor development and cachexia were significantly higher in the OT group compared to the CT group, and botryosphaeran attenuated these parameters. OT rats presented accumulation of adipose tissue, reduced muscle mass, glucose intolerance, insulin resistance, hyperglycemia, anemia, leukocytosis, and thrombocytopenia. Botryosphaeran corrected insulin resistance and hyperglycemia, modulated cholesterol levels, and increased leukocyte and lymphocytes in obese rats, which can be attributable to an inflammatory response against the Walker-256 tumor, contributing to a lower tumor development. Our data demonstrated that botryosphaeran was effective in attenuating tumor growth and in improving the metabolic and hematological profiles of the tumor-bearing rats, demonstrating its potential role in the cancer's management.

Variable levels of introgression between the endangered Podarcis carbonelli and highly divergent congeneric species.

Recent empirical studies have demonstrated that speciation with gene flow is more common than previously thought. From a conservation perspective, the potential negative effects of hybridization raise concerns on the genetic integrity of endangered species. However, introgressive hybridization has also been growingly recognized as a source of diversity and new advantageous alleles. Carbonell's wall lizard (Podarcis carbonelli) is an endangered species whose distribution overlaps with four other congeneric species. Our goal here was to determine whether P. carbonelli is completely reproductively isolated from its congeners and to evaluate the relevance of hybridization and interspecific gene flow for developing a conservation plan. We used restriction site associated DNA (RAD) sequencing to discover SNPs in samples from four contact zones between P. carbonelli and four other species. Principal component analysis, multilocus genotype assignment and interspecific heterozygosity suggest incomplete reproductive isolation and ongoing gene flow between species. However, hybridization dynamics vary across all pairs, suggesting complex interactions between multiple intrinsic and extrinsic barriers. Despite seemingly ubiquitous interspecific gene flow, we found evidence of strong reproductive isolation across most contact zones. Instead, indirect effects of hybridization like waste of reproductive effort in small isolated populations may be more problematic. Our results highlight the need to further evaluate the consequences of introgression for P. carbonelli, both on a geographic and genomic level and included in a comprehensive and urgently needed conservation plan. Besides, those findings will add important insights on the potential effects of hybridization and introgression for endangered species.

Atypical cyclins: the extended family portrait.

Regulation of cell division is orchestrated by cyclins, which bind and activate their catalytic workmates, the cyclin-dependent kinases (CDKs). Cyclins have been traditionally defined by an oscillating (cyclic) pattern of expression and by the presence of a characteristic "cyclin box" that determines binding to the CDKs. Noteworthy, the Human Genome Sequence Project unveiled the existence of several other proteins containing the "cyclin box" domain. These potential "cyclins" have been named new, orphan or atypical, creating a conundrum in cyclins nomenclature. Moreover, although many years have passed after their discovery, the scarcity of information regarding these possible members of the family has hampered the establishment of criteria for systematization. Here, we discuss the criteria that define cyclins and we propose a classification and nomenclature update based on structural features, interactors, and phylogenetic information. The application of these criteria allows to systematically define, for the first time, the subfamily of atypical cyclins and enables the use of a common nomenclature for this extended family.

Frontline treatment for transplant-eligible multiple myeloma: A 6474 patients network meta-analysis.

Autologous transplantation continues to be the cornerstone of younger and fit multiple myeloma patients. It is known that frontline induction therapy before transplantation can influence post-transplant results. Therefore, best frontline treatment for transplant-eligible patients should be based on best available evidence to guide therapy. Furthermore, until now due to data scarcity, it was not possible to thoroughly compare lenalidomide to other regimens in this setting. We performed a systematic review and network (mixed treatment comparison) meta-analysis of 21 clinical trial publications, enrolling 6474 patients and comparing 11 different treatment frontline setting regimens regarding survival, response, and safety outcomes. OS analysis showed superiority of CRD (cyclophosphamide-lenalidomide-dexamethasone) over TD-based (thalidomide-dexamethasone, HR = 0.76,0.62-0.90), VAD-based (HR = 0.71,0.52-0.90), and Z-Dex (idarubicin-dexamethasone, HR = 0.37,0.17-0.76) regimens. Concerning PFS, VTD (bortezomib-thalidomide-dexametasone) showed superior results when compared with TD-based (HR = 0.66,0.51-0.84), VAD-based (HR = 0.61,0.46-0.82), Z-Dex (HR = 0.42,0.22-0.78), and high dose dexamethasone (Dex, HR = 0.62,0.41-0.90) regimens. Bortezomib/thalidomide regimens were not superior to lenalidomide, considering these outcomes. Also, concerning complete and overall response, VTD ranked first among other regimens, showing clear superiority over thalidomide-only containing protocols. Safety outcome evaluated infectious, cardiac, gastrointestinal, neurological, thrombotic, and hematological grade 3 to 4 adverse events. Risk of thrombotic events was higher with TAD (thalidomide-doxorubicin-dexamethasone), neurological with PAD (bortezomib-doxorubicin-dexamethasone), infectious with Dex, hematological with Z-Dex, gastrointestinal with VTD, and cardiac with PAD regimens. Our study endorses current recommendations on combined immunomodulatory drugs and proteasome inhibitors frontline regimens (in triplets) in transplant-eligible multiple myeloma patients, but also formally demonstrates the favorable performance of lenalidomide in overall and progression-free survival, when compared with bortezomib/thalidomide protocols.

Colored shade nets induced changes in growth, anatomy and essential oil of Pogostemon cablin.

The purpose of this investigation was to determine the influence of colored shade nets on the growth, anatomy and essential oil content, yield and chemical composition of Pogostemon cablin. The plants were cultivated under full sunlight, black, blue and red nets. The harvesting was performed 5 months after planting and it was followed by the analysis of plant growth parameters, leaf anatomy, essential oil content, yield and chemical composition. The plants grown under red net have produced more leaf, shoot, total dry weight and leaf area. Plants cultivated under colored nets showed differences in morphological features. Plants maintained under red net had a higher leaf blade thickness and polar and equatorial diameter of the stomata ratio. Additionally, higher yield of essential oil in the leaves was observed under red and blue colored shade net. The essential oil of the plants grown under red net showed the highest relative percentage of patchoulol (66.84%). Therefore, it is possible using colored shade nets to manipulate P. cablin growth, as well as its essential oil production with several chemical compositions. The analyses of principal components allowed observing that pogostol has negative correlation with α-guaiene and α-bulnesene. There was difference in total dry weight and patchoulol content when the patchouli is cultured under the red colored shade nets.

New technique of intragastric sleeve: viability and survival in a pig model.

Developing a less invasive, practical and cost-effective operative technique for obesity treatment represents a pressing need for our society. In this way, intragastric single port sleeve by endoplication was tested in six pigs during 18 weeks. Celiotomy was performed with animal placed in dorsal decubitus position. Single port gastrostomy was performed and double tobacco pouch sutures were made in fundic region, making a gastric sleeve. At the end, stomach layers and skin were closed in a conventional manner. Means and the standard deviations of surgical time were calculated. The procedure was simple and all animals survived; there were no significant blood loss and no intra and postoperative complications. The procedure was fast (67.4 minutes). The technique has the advantage of not requiring the use of mechanical sutures, making it less costly. The innovation of this procedure was the use of a single port gastrostomy device to perform an intraluminal sleeve. What made this technique less invasive were the use of a single port, nonmanipulation of the stomach intra-abdominally, ease of execution and no need of pneumoperitoneum. The new technique is acceptable and has reproducible viability, had a short procedure time without intra and postoperative complications.

Human Argonaute 2 Is Tethered to Ribosomal RNA through MicroRNA Interactions.

The primary role of the RNAi machinery is to promote mRNA degradation within the cytoplasm in a microRNA-dependent manner. However, both Dicer and the Argonaute protein family have expanded roles in gene regulation within the nucleus. To further our understanding of this role, we have identified chromatin binding sites for AGO2 throughout the 45S region of the human rRNA gene. The location of these sites was mirrored by the positions of AGO2 cross-linking sites identified via PAR-CLIP-seq. AGO2 binding to the rRNA within the nucleus was confirmed by RNA immunoprecipitation and quantitative-PCR. To explore a possible mechanism by which AGO2 could be recruited to the rRNA, we identified 1174 regions within the 45S rRNA transcript that have the ability to form a perfect duplex with position 2-6 (seed sequence) of each microRNA expressed in HEK293T cells. Of these potential AGO2 binding sites, 479 occurred within experimentally verified AGO2-rRNA cross-linking sites. The ability of AGO2 to cross-link to rRNA was almost completely lost in a DICER knock-out cell line. The transfection of miR-92a-2-3p into the noDICE cell line facilitated AGO2 cross-linking at a region of the rRNA that has a perfect seed match at positions 3-8, including a single G-U base pair. Knockdown of AGO2 within HEK293T cells causes a slight, but statistically significant increase in the overall rRNA synthesis rate but did not impact the ratio of processing intermediates or the recruitment of the Pol I transcription factor UBTF.

Polyphosphate: popping up from oblivion.

Phosphate is one of the essential elements supporting life. Cells accumulate phosphate in the form of a molecule called polyphosphate (polyP), which carries many functions in the physiology of cells that have not been wholly elucidated. Polyphosphate is present in all the types of cells from bacteria to mammals. It consists of a linear polymer constructed with anywhere from a few to hundreds of inorganic phosphate (Pi) molecules linked by phosphoanhydride bonds. Although polyP was described many years ago, difficulties in the study of its roles, most likely due to the many processes polyP is involved in and incomplete information obtained from multiple models and organisms relegate polyP into oblivion. But now, several interesting pieces of evidence are resurrecting the polyP as a key molecule in processes, such as protein folding, carbon metabolism, cell cycle progression, dNTP synthesis, and genomic stability. In this contribution, in addition to briefly summarize the polyP history and roles, we discuss its involvement in supporting cell cycle progression and genomic stability as well as the implications for the truthful replication of genomes.

Perception of nursing and medical professionals on patient safety in neonatal intensive care units. / Segurança do paciente na percepção da enfermagem e medicina em unidades de terapia intensiva neonatal.

OBJECTIVE: To describe patient safety in the perception of nursing and medical professionals of neonatal intensive care units. METHOD: Exploratory and descriptive study with a qualitative approach, using the instrument Hospital Survey on Patient Safety Culture for data collection. Twenty-eight nursing and medical professionals of three neonatal intensive care units in the city of Florianópolis, state of Santa Catarina, participated in the study, from 2013 to 2015. Content thematic analysis was used for data analysis. RESULTS: The following categories emerged: perception and strategies for patient safety; risk factors that interfere with patient safety; challenges in the communication of errors associated with health care. CONCLUSIONS: Patient safety in the perception of professionals reflected the importance of safe care and the identification of risk factors in work conditions, predisposing to errors. Communication of risk situations, development of safety culture, and qualification are of utmost importance.