Menadione and protocatechuic acid: A drug combination with antitumor effects in murine osteosarcoma cells.

Osteosarcoma (OS) is a primary malignant bone tumor that has an abnormal expression of oncogenesis and tumor suppressors and causes dysregulation of various signaling pathways. Thus, novel therapeutic strategies for OS are needed to overcome the resistance of traditional treatments. This study evaluated the cytotoxic and anticancer effects of the association between menadione (MEN) and protocatechuic acid (PCA) in murine OS cells (UMR-106). The concentrations were 3.12 µM of isolated MEN, 500 µM of isolated PCA, and their associations. We performed cell viability assays, morphology modification analysis, cell migration by the wound-healing method, apoptosis by flow cytometry, reactive oxygen species (ROS) production, gene expression of NOX by RT-qPCR, and degradation of MMP-2 and 9 by zymography. Our results showed that the association of MEN+PCA was more effective in OS cells than the compounds alone. The association decreased cell viability, delayed cell migration, and decreased the expression of NOX-2 and ROS. In addition, the MEN+PCA association induced a slight increase in the apoptotic process. In summary, the association can enhance the compound's antitumor effects and establish a higher selectivity for tumor cells, possibly caused by significant mitochondrial damage and antioxidant properties.

The role of the visceral adiposity index in the assessment of metabolic syndrome of polycystic ovary syndrome patients: a new anthropometric index.

PURPOSE: Polycystic ovary syndrome (PCOS) is a common endocrine disorder often linked to metabolic syndrome (MS), raising the risk of cardiovascular disease and type II diabetes. Certain indicators, such as the lipid accumulation product (LAP) and homeostatic model assessment for insulin resistance (HOMA-IR), can predict MS in PCOS patients. This study aimed to assess the predictive power of the visceral adiposity index (VAI) in comparison to LAP and HOMA-IR as predictors of MS in PCOS patients. METHODS: In this cross-sectional observational study, data from 317 diagnosed PCOS women were analyzed. VAI, LAP, and HOMA-IR were computed as indexes. Participants were categorized into two groups for index accuracy comparison: PCOS patients with and without MS. The data were assessed using a ROC curve. RESULTS: Among PCOS women with MS, 92.3% had abnormal VAI results, 94.5% had abnormal LAP results, and only 50.5% had abnormal HOMA-IR results. Conversely, the majority of PCOS women without MS had normal HOMA-IR (64.6%). When comparing these indexes using the ROC curve, VAI displayed the highest accuracy, followed by LAP and HOMA-IR. CONCLUSION: The VAI index proved to be a superior predictor of metabolic MS in PCOS women when compared to other indexes.

In-hospital breastfeeding and predictive factors during the SARS-CoV-2 pandemic: A retrospective cohort study - Aleitamento materno hospitalar e fatores preditores durante a pandemia pelo SARS-CoV-2: Coorte retrospectiva.

PURPOSE: To analyze breastfeeding and the factors that positively influence the first hour of life, during hospitalization, and at discharge during the SARS-CoV-2 pandemic. DESIGN AND METHOD: This is a retrospective cohort study, with data collected from medical records. Consisting of 225 mother-newborn dyads with deliveries between 2020 and 2021. Breastfeeding in the first hour of life, during hospitalization, and at discharge was considered as the outcome variable. The independent variables were sociodemographic, obstetric, and neonatal data. The analysis was performed with bivariate and multivariate regression through a generalized linear model (Poisson family), with a 5% significance level. It was approved by the Institutional Review Board (IRB), under approval number 4,911,317. RESULT: Newborns of women without COVID-19 suspicion or diagnosis and who had skin-to-skin contact with their mother at birth are twice as likely to be breastfed in the first hour of life. Absence of complications in the newborn during hospitalization and no COVID-19 suspicion or diagnosis double the exclusive breastfeeding rate during hospitalization. Newborns exclusively breastfed during hospitalization present 1.6 times more chances of being exclusively breastfeeding at hospital discharge. CONCLUSION: It was evidence that women who gave birth without COVID-19 suspicion, and newborns who had skin-to-skin contact with their mother at birth represented a predictive factor for favoring exclusive breastfeeding. PRACTICE IMPLICATIONS: This research contributes to the innovation of evaluating breastfeeding in the newborn's first hour of life, during hospitalization, and at discharge in a pandemic context.

SOX3 duplication in a boy with 46,XX ovotesticular disorder of sex development and his 46,XX sister with atypical genitalia: Probable germline mosaicism.

Ovotesticular disorders of sex development (OT-DSD) are characterized by ovarian follicles and seminiferous tubules in the same individual, with a wide range of atypical genitalia. We report on two sibs with atypical genitalia and SRY-negative 46,XX DSD, OT-DSD was confirmed only in the boy, while the girl had bilateral ovaries. Chromosome microarray analysis (CMA) showed a 737-kb duplication at Xq27.1 including the entire SOX3 gene in both sibs, which was confirmed by quantitative real time PCR. Also, X chromosome inactivation assay showed random inactivation in both sibs. Whole exome sequencing revealed no pathogenic or likely pathogenic variant. CMA of the parents showed normal results for both, suggesting that germline mosaicism could be the reason of recurrence of this duplication in the siblings. Our results support a pathogenic role of SOX3 overexpression in 46,XX subjects leading to variable DSD phenotypes.

Pro-adherence complementary audiovisual educational intervention model for chronic myeloid leukemia patients treated with imatinib mesylate.

BACKGROUND: Imatinib mesylate (IM) treatment adherence is a challenge, especially in an economic-social population neglected from developing countries. OBJECTIVE: To create a new complementary audiovisual educational intervention model to improve IM treatment adherence of CML patients. METHODS: Two adherence verification methods were applied before and after intervention: modified Morisky-Green test and molecular responses (BCR-ABL transcripts quantification). Adherence estimates were calculated using univariate and multivariate component analysis (MCA) for the socio-demographic and clinical characteristics of patients. RESULTS: Modified Morisky-Green test results demonstrated a substantial increase of CML patient adherence from 23% (pre-film) to 65% (post-film). Greater improvement was obtained for patients presenting major molecular response (MMR) from 38% (pre-film) to 60% (post-film). Although slight gain for complete molecular response (CMR) from 23% (pre-film) to 26% (post-film) was achieved, it represents a total tumour regression. MCA identified that females <50 years-old, using less than two medications (no disease associated) and CMR condition were the most benefited with intervention. CONCLUSION: Audiovisual educational intervention was an effective complementary pro-adherence model, activating patient memory and improving IM treatment adherence. Although this intervention shows effective, not all patients responded as expected, being necessary a combination of educational and clinical interventions to improve IM adherence.

Influence of simulation design on stress, anxiety and self-confidence of nursing students: Systematic review with meta-analysis.

AIM: To evaluate the simulation design characteristics that may influence the stress, anxiety and self-confidence of undergraduate nursing students during learning. DESIGN: Systematic review with meta-analysis. DATA SOURCES: Searchers were conducted in October 2020 and updated in August 2022 in the databases CENTRAL, CINAHL, Embase®, ERIC, LILACS, MEDLINE, PsycINFO®, Scopus and Web of Science, PQDT Open (ProQuest), BDTD, Google Scholar and specific journals on simulation. REVIEW METHODS: This review was conducted according to the recommendations of Cochrane Handbook for Systematic Reviews and reported according to the PRISMA Statement. Experimental and quasi-experimental studies that compared the effect of simulation on stress, anxiety and self-confidence of nursing students were included. The selection of studies and data extraction was performed independently by two reviewers. Simulation information was collected as prebriefing, scenario, debriefing, duration, modality, fidelity and simulator. Data summarization was performed by qualitative synthesis and meta-analytical methods. RESULTS: Eighty studies were included in the review, and most reported in detail the structure of the simulation, contemplating prebriefing, scenario, debriefing and the duration of each step. In subgroup meta-analysis, the presence of prebriefing, duration of more than 60 min and high-fidelity simulations helped reduce anxiety, while the presence of prebriefing and debriefing, duration, immersive clinical simulation modalities and procedure simulation, high-fidelity simulations and use of mannequins, standardised patients and virtual simulators, contributed to greater students' self-confidence. CONCLUSIONS: Different modulations of simulation design components imply reduction of anxiety and increased self-confidence in nursing students, especially highlighting the quality of the methodological report of simulation interventions. RELEVANCE TO CLINICAL PRACTICE: These findings help to support the need of more rigorous methodology in simulation designs and research methods. Consequently, impact on the education of qualified professionals prepared to work in clinical practice. No Patient or Public Contribution.

Symptoms of Depression in the Postpartum Period: Targeting Maternal Mental Health in the Perinatal Period.

This cross-sectional study aimed to examine the relationship between postpartum depression symptoms, anxiety, and stress during the postpartum period. A total of 101 women were assessed using the Depression, Anxiety and Stress Scale (DASS-21) and the Edinburgh Postnatal Depression Scale (EPDS) within 14 days after delivery. Multivariate regression analysis revealed that paid work, tobacco use, and stress symptoms were significantly associated with a higher incidence of postpartum depression symptoms. These results underscore the importance of comprehensive prenatal care and effective postpartum follow-up to address maternal mental health and prevent adverse outcomes for both mothers and children.

Articular cartilage degeneration and bone adaptation due to lack of dystrophin in mice.

INTRODUCTION: Duchenne muscular dystrophy is caused by the absence of dystrophin. This study aimed to investigate femoral morphological characteristics of lack of dystrophin in MDX mice, considering that this model, different from DMD patient, is not influenced by corticosteroids administration and limited ambulation. MATERIALS AND METHODS: Proximal femur of male 16-week-old Control and MDX mice were submitted to histological, morphometric (volume density of articular cartilage, compact bone, trabecular bone and bone marrow; articular cartilage layers area; articular cartilage cell area), and immunohistochemistry analysis for RUNX-2, RANK-L, MMP-2, MMP-9, Caspase-3 and KI-67. RESULTS: MDX showed loss of linearity of articular cartilage with subchondral bone transition and elevation of this subchondral bone to the articular surface when compared with control. In addition, MDX presented morphological difference in the pantographic network of collagen fibers. Volume density of trabecular bone tissue was higher in the MDX than Control, but volume density of articular cartilage was lower in MDX (p < 0.05). The articular cartilage layers and chondrocytes area were significantly smaller in MDX than Control. These results associated to MMPs and osteogenic markers of proximal femur revealed an adaptation process as a consequence of lack of dystrophin. CONCLUSIONS: The morphological changes observed in the bone tissue of the MDX may be not only secondary to muscle weakness or chronic use of corticosteroids but also our results indicate connections between decrease of cartilage thickness, collagen network alteration and consequent subchondral changes that may lead to articular cartilage degeneration and bone adaptation mechanism in MDX mice.

The Colombian Strain of Trypanosoma cruzi Induces a Proinflammatory Profile, Neuronal Death, and Collagen Deposition in the Intestine of C57BL/6 Mice Both during the Acute and Early Chronic Phase.

The objective of this study was to evaluate the histopathological changes caused by infection with the Colombian strain of Trypanosoma cruzi (T. cruzi) in the acute and chronic experimental phases. C57Bl/6 mice were infected with 1000 trypomastigote forms of the Colombian strain of T. cruzi. After 30 days (acute phase) and 90 days (early chronic phase) of infection, the animals were euthanized, and the colon was collected and divided into two parts: proximal and distal. The distal portion was used for histopathological analysis, whereas the proximal portion was used for quantification of pro- and anti-inflammatory cytokines. In addition, the weight of the animals and parasitemia were assessed. The infection induced gradual weight loss in the animals. In addition, the infection induced an increase in interferon gamma (IFNγ) and tumor necrosis factor-alpha (TNF-α) in the intestine in the acute phase, in which this increase continued until the early chronic phase. The same was observed in relation to the presence of intestinal inflammatory infiltrates. In relation to interleukin (IL)-10, there was an increase only in the early chronic phase. The Colombian strain infection was also able to induce neuronal loss in the myenteric plexus and deposition of the collagen fibers during the acute phase. The Colombian strain of T. cruzi is capable of causing histopathological changes in the intestine of infected mice, especially in inducing neuronal destructions. Thus, this strain can also be used to study the intestinal form of Chagas disease in experimental models.

COVID-19 and Lung Mast Cells: The Kallikrein-Kinin Activation Pathway.

Mast cells (MCs) have relevant participation in inflammatory and vascular hyperpermeability events, responsible for the action of the kallikrein-kinin system (KKS), that affect patients inflicted by the severe form of COVID-19. Given a higher number of activated MCs present in COVID-19 patients and their association with vascular hyperpermeability events, we investigated the factors that lead to the activation and degranulation of these cells and their harmful effects on the alveolar septum environment provided by the action of its mediators. Therefore, the pyroptotic processes throughout caspase-1 (CASP-1) and alarmin interleukin-33 (IL-33) secretion were investigated, along with the immunoexpression of angiotensin-converting enzyme 2 (ACE2), bradykinin receptor B1 (B1R) and bradykinin receptor B2 (B2R) on post-mortem lung samples from 24 patients affected by COVID-19. The results were compared to 10 patients affected by H1N1pdm09 and 11 control patients. As a result of the inflammatory processes induced by SARS-CoV-2, the activation by immunoglobulin E (IgE) and degranulation of tryptase, as well as Toluidine Blue metachromatic (TB)-stained MCs of the interstitial and perivascular regions of the same groups were also counted. An increased immunoexpression of the tissue biomarkers CASP-1, IL-33, ACE2, B1R and B2R was observed in the alveolar septum of the COVID-19 patients, associated with a higher density of IgE+ MCs, tryptase+ MCs and TB-stained MCs, in addition to the presence of intra-alveolar edema. These findings suggest the direct correlation of MCs with vascular hyperpermeability, edema and diffuse alveolar damage (DAD) events that affect patients with a severe form of this disease. The role of KKS activation in events involving the exacerbated increase in vascular permeability and its direct link with the conditions that precede intra-alveolar edema, and the consequent DAD, is evidenced. Therapy with drugs that inhibit the activation/degranulation of MCs can prevent the worsening of the prognosis and provide a better outcome for the patient.

Consequences of ankle joint immobilisation: insights from a morphometric analysis about fibre typification, intramuscular connective tissue, and muscle spindle in rats.

Orthosis immobilisations are routinely used in orthopaedic procedures. This intervention is applicable in bone fractures, ligament injuries, and tendonitis, among other disorders of the musculoskeletal system. We aimed to evaluate the effects of ankle joint functional immobilisation on muscle fibre morphology, connective tissue, muscle spindle and fibre typification triggered by a novel metallic orthosis. We developed a rodent-proof experimental orthosis able to hold the tibiotalar joint in a functional position for short and long terms. The tibialis anterior muscles of free and immobilised legs were collected and stained by histology and histochemistry techniques to investigate general muscle morphology, connective tissue and muscle fibre typification. Morphometric analysis of muscle cross-section area, fibre type cross-section area, fibre type density, percentage of intramuscular connective tissue, and thickness of the muscle spindle capsule were obtained to gain insights into the experimental protocol. We found that short- and long-term immobilisation decreased the cross-section area of the muscles and induced centralisation of myonuclei. The connective tissue of immobilised muscle increased after 2 and 4 weeks mainly by deposition of type III and type I collagen fibres in the perimysium and endomysium, respectively, in addition to muscle spindle capsule thickening. Type IIB muscle fibre was severely affected in our study; the profile assumed odd shapes, and our data suggest interconversion of these fibre types within long-term immobilisation. In conclusion, our protocol has produced structural and histochemical changes in muscle biology. This method might be applied to various rodent models that enable genetic manipulation for the investigation of muscle degeneration/regeneration processes.

Insulin Modulates Myogenesis and Muscle Atrophy Resulting From Skin Scald Burn in Young Male Rats.

BACKGROUND: Burn injuries (BIs) due to scalding are one of the most common accidents among children. BIs greater than 40% of total body surface area are considered extensive and result in local and systemic response. We sought to assess morphological and myogenic mechanisms through both short- and long-term intensive insulin therapies that affect the skeletal muscle after extensive skin BI in young rats. MATERIALS AND METHODS: Wistar rats aged 21 d were distributed into four groups: control (C), control with insulin (C + I), scald burn injury (SI), and SI with insulin (SI + I). The SI groups were submitted to a 45% total body surface area burn, and the C + I and SI + I groups received insulin (5 UI/Kg/d) for 4 or 14 d. Glucose tolerance and the homeostatic model assessment of insulin resistance index were determined. Gastrocnemius muscles were analyzed for histopathological, morphometric, and immunohistochemical myogenic parameters (Pax7, MyoD, and MyoG); in addition, the expression of genes related to muscle atrophy (MuRF1 and MAFbx) and its regulation (IGF-1) were also assessed. RESULTS: Short-term treatment with insulin favored muscle regeneration by primary myogenesis and decreased muscle atrophy in animals with BIs, whereas the long-term treatment modulated myogenesis by increasing the MyoD protein. Both treatments improved histopathological parameters and secondary myogenesis by increasing the MyoG protein. CONCLUSIONS: Treatment with insulin benefits myogenic parameters during regeneration and modulates MuRF1, an important mediator of muscle atrophy.

Are visual inspection and digital palpation reliable methods to assess ability to perform a pelvic floor muscle contraction? An intra-rater study.

AIMS: To investigate the intrarater reliability of visual inspection and digital palpation to classify women's ability to perform a voluntary pelvic floor muscle (PFM) contraction and the association between the two methods. METHODS: This was a test-retest clinical study including 44 women. The ability to perform a PFM voluntary contraction was evaluated two times in all participants using visual inspection and digital palpation. All analyzed participants were assessed with a 7-day interval between the two assessments and by the same examiner. Kappa's agreement coefficient was used to estimate the intrarater reliability, and Fisher's exact test was used to analyze association between the two methods. RESULTS: This study found a substantial intrarater reliability of visual inspection (k = 0.73; p < .001) and digital palpation (k = 0.74; p < .001). A significant association between visual inspection and digital palpation was found at both time points (p < .001). CONCLUSION: Both visual inspection and digital palpation have substantial intrarater reliability and visual inspection can be recommended when vaginal palpation is not tolerated.

Immunolocalization of stem/progenitor cell biomarkers Oct-4, C-kit and Musashi-1 in endometriotic lesions.

BACKGROUND: Human endometrium harbors stem/progenitor cells (SPCs) that may contribute to the establishment of endometriosis when seeded outside the uterus. Oct-4, C-kit and Musashi-1 are some of the many proteins used to characterize SPCs, but their association with endometriosis is uncertain. OBJECTIVE AND DESIGN: In this study, specimens of normal endometrium (n = 12), eutopic endometrium from women with endometriosis (n = 9), superficial peritoneal endometriosis (SUP, n = 12) and deep endometriosis (DE, n = 13) lesions were evaluated for localization and intensity of immunostaining for Oct-4, C-kit and Musashi-1. RESULTS: The three markers were abundantly expressed in normal endometrium, eutopic endometrium from endometriosis patients, SUP and DE specimens. Oct-4 and C-kit expression did not vary across groups as regards intensity or frequency. C-kit staining signal was seldom detected in vascular endothelium of normal or eutopic endometrium from endometriosis patients; however, it was positive in 67% of the SUP lesions and in 25% of the DE lesions (p = 0.042). Musashi-1 was expressed in some endometriotic glands as cell clusters, but its signal was similar between the four types of tissue (p = 0.971) CONCLUSION: The wide distribution of Oct-4, C-kit and Musashi-1 in endometria of patients with and without endometriosis and in SUP and DE endometriotic lesions suggests that these markers are not suitable for the in situ characterization of endometrial SPCs and should not be taken as surrogates for the study of SPCs in the pathogenesis of endometriosis.

Pain scores at the insertion of the 52 MG levonorgestrel-releasing intrauterine system among nulligravidas and parous women.

PURPOSE: This study aimed to assess the pain scores at the insertion of the 52 mg levonorgestrel-releasing intrauterine system (LNG-IUS) among nulligravidas, parous women with previous vaginal delivery and parous women with elective caesarean-delivery without any previous labour or cervix dilation. MATERIALS AND METHODS: The present research is a prospective, single-cohort study that included 413 women aged 15-49 years who opted for LNG-IUS placement for contraception or treatment of heavy menstrual bleeding. Women who participated in the present study were not submitted to any pharmacological pain-relieving intervention to perform the procedure. Pain at insertion was evaluated by using a Visual Analogue Scale (VAS). Pain was classified as absent (0), mild (1-3), moderate (4-6), or severe (7-10). The women were divided as: (1) nulligravidas, (2) parous women with a previous vaginal delivery, or (3) parous women with elective caesarean-delivery without any previous labour or cervix dilation. RESULTS: Nulligravidas women presented a higher mean pain score, when compared to women with elective caesarean-delivery and women with previous vaginal delivery (6.6 ± 2.0 vs 5.5 ± 2.1 and 3.9 ± 2.4, respectively; p < 0.001). Nulligravidas and women with elective caesarean-delivery were more likely to have pain classified as moderate or severe (in relation to absent or mild) than women with previous vaginal delivery (p < 0.001). Multiple Linear Regression Analysis demonstrated that 29.5% of all variability of the pain score was explained by two predictor/independent variables: nulligravidas or women with elective caesarean and difficulty at IUD insertion. CONCLUSIONS: Women with previous vaginal delivery had lower pain scores at LNG-IUS insertion when compared to nulligravidas and women with elective caesarean-delivery without any previous labour.

Sleep Deprivation Interferes with JAK/STAT Signaling Pathway and Myogenesis in the Masseter Muscle of Rats.

OBJECTIVES: The aim of the study was to study the Janus kinase/tyrosine kinase-activated transduction factor (JAK/STAT) signaling pathway and myogenesis on the masseter muscle after sleep deprivation and to investigate the role of stress in this scenario. SUBJECTS AND METHODS: A total of 18 male Wistar rats were divided into the following groups: control (n = 6): animals were not submitted to any procedures, and paradoxical sleep deprivation and vehicle (PSD + V; n = 6): animals were subjected to PSD for 96 h and (PSD + MET; n = 6): animals were subjected to PSD for 96 h with administration of metyrapone. Paradoxical sleep deprivation was performed by the modified multiple platforms method. Histopathological analysis, histomorphometry, and immunohistochemistry were performed. RESULTS: The results showed the presence of inflammatory infiltrate in the PSD + V and PSD + MET groups and atrophy. Histomorphometry showed that the cellular profile area decreased, while cellular density increased in both experimental groups. Expression of p-STAT 3, MyoD, and MyoG increased in the PSD + V group, while the PSD + MET group showed increased expression of IL-6 and p-STAT 3. CONCLUSION: Our results suggest that sleep deprivation induces an inflammatory response and atrophy in the masseter muscle of rats.

Fluoride effects on cell viability and ENaC expression in kidney epithelial cells.

Fluoride (F) at micromolar (µM) concentrations induces apoptosis in several cell lines. Moreover, proteomic studies have shown major changes in the profile of proteins involved in signal transduction. These effects may negatively affect ion transport in the kidneys. The activity of epithelial sodium channels (ENaCs) is a limiting factor for sodium and water resorption in the kidneys, which is essential for the maintenance of the electrolyte balance and homeostasis of the body. Here we investigated the effects of F, at different concentrations (10, 40, 100, 200, and 400 µM), on the viability of renal epithelial cells (M-1), and ENaC expression. We showed that sodium fluoride (NaF) reduces cell viability in a concentration-dependent manner (p < 0.05) up to a 96-h time-point when compared to control. Sodium fluoride at moderate concentrations (100 and 200 µM), upregulated the ENaC subunit genes Scnn1a and Scnn1g, but not Scnn1b. Sodium fluoride downregulated all three ENaC subunit genes at a higher concentration of 400 µM (p < 0.05). Immunofluorescence analysis showed that Scnn1a and Scnn1g expression was decreased within 24 h of NaF treatment. After 48 h, NaF (400 µM) increased the expression of Scnn1a but not Scnn1g. However, NaF decreased the expression of Scnn1g at all studied concentrations. We conclude that F, at µM concentrations, modulates the expression of ENaC subunit genes, which is likely to significantly affect molecular signaling in kidney epithelial cells.

Phosphatidylserine controls calcium phosphate nucleation and growth on lipid monolayers: A physicochemical understanding of matrix vesicle-driven biomineralization.

Bone biomineralization is an exquisite process by which a hierarchically organized mineral matrix is formed. Growing evidence has uncovered the involvement of one class of extracellular vesicles, named matrix vesicles (MVs), in the formation and delivery of the first mineral nuclei to direct collagen mineralization. MVs are released by mineralization-competent cells equipped with a specific biochemical machinery to initiate mineral formation. However, little is known about the mechanisms by which MVs can trigger this process. Here, we present a combination of in situ investigations and ex vivo analysis of MVs extracted from growing-femurs of chicken embryos to investigate the role played by phosphatidylserine (PS) in the formation of mineral nuclei. By using self-assembled Langmuir monolayers, we reconstructed the nucleation core - a PS-enriched motif thought to trigger mineral formation in the lumen of MVs. In situ infrared spectroscopy of Langmuir monolayers and ex situ analysis by transmission electron microscopy evidenced that mineralization was achieved in supersaturated solutions only when PS was present. PS nucleated amorphous calcium phosphate that converted into biomimetic apatite. By using monolayers containing lipids extracted from native MVs, mineral formation was also evidenced in a manner that resembles the artificial PS-enriched monolayers. PS-enrichment in lipid monolayers creates nanodomains for local increase of supersaturation, leading to the nucleation of ACP at the interface through a multistep process. We posited that PS-mediated nucleation could be a predominant mechanism to produce the very first mineral nuclei during MV-driven bone/cartilage biomineralization.

Effects of Short Term Metformin Treatment on Brown Adipose Tissue Activity and Plasma Irisin Levels in Women with Polycystic Ovary Syndrome: A Randomized Controlled Trial.

Polycystic ovary syndrome (PCOS) is a chronic dysfunction associated with obesity and metabolic disorders that can be ameliorated by treatment with metformin. Brown adipose tissue (BAT) has been recently identified in adult humans, and irisin is a myokine that induces BAT formation. The aim of this randomized controlled trial was to evaluate whether a short term treatment with metformin alters BAT activity and plasma irisin levels in women with PCOS. The participants were randomly assigned to receive metformin (1500 mg/day, n=21) or placebo (n=24) during 60 days. BAT activity was assessed by 18F-FDG positron emission tomography-computed tomography (PET-CT) and plasma irisin levels were measured by enzyme immunoassay. The groups were similar in age, body measures, metabolic profile and PCOS phenotypes. BAT activity did not change significantly in the women treated with metformin (median Δ SUVmax=-0.06 g/ml, interquartile interval -2.81 to 0.24 g/ml, p=0.484, Wilcoxon's test) or placebo (median Δ SUVmax=0.98 g/ml, interquartile interval -2.94 to 4.60 g/ml, p=0.386). In addition, plasma irisin levels remained unchanged in the groups treated with metformin (median Δ=-98 ng/ml, interquartile interval -366 to 60 ng/ml, p=0.310) and placebo (median Δ=28 ng/ml, interquartile interval -1260 to 215 ng/ml, p=0.650). These results suggest that in PCOS women BAT activity and plasma irisin levels may not change after a brief treatment with metformin.

Extensive burn injury causes bone collagen network alteration and growth delay related to RANK-L immunoexpression change.

PURPOSE: Extensive burn injury mainly affects children, and hypermetabolic state can lead to growth delay. This study aimed to investigate bone histopathological and morphometric aspects, collagen fibers network and the immunoexpression of biological markers related to bone development in a young experimental model for extensive burn. MATERIALS AND METHODS: A total of 28 male Wistar rats were distributed into Control (C) and subjected to scald burn injury (SBI) groups. Sham or injured animals were euthanized 4 or 14 days post-lesion and proximal epiphyses of the femur were submitted to histological, morphometric (thickness epiphyseal plate), and RUNX-2 and receptor activator of nuclear factor kappa- ß ligand (RANK-L) immunoexpression methods. RESULTS: Histopathological femoral findings showed delayed appearance of the secondary ossification center in SBI, 14 days post-injury. Collagen fibers 4 days after injury were observed in articular cartilage as a pantographic network with a transversally oriented lozenge-shaped mesh, but this network was thinner in SBI. Fourteen days after the injury, the pantographic network of collagen presented square-shaped mesh in C, but this aspect was changed to a wider mesh in SBI. Morphometric analysis of epiphyseal plate revealed that the SBI group had less thickness than the respective controls (p<0.05). RUNX-2 showed no difference between groups, but RANK-L score was higher in all SBI groups. CONCLUSIONS: Extensive burn injury causes delayed bone growth and morphological changes. Alterations in collagen network and enhancement in immunoreactivity of RANK-L result in increased osteoclastogenesis.