Consistency of convolutional neural networks in dermoscopic melanoma recognition: A prospective real-world study about the pitfalls of augmented intelligence.

BACKGROUND: Deep-learning convolutional neural networks (CNNs) have outperformed even experienced dermatologists in dermoscopic melanoma detection under controlled conditions. It remains unexplored how real-world dermoscopic image transformations affect CNN robustness. OBJECTIVES: To investigate the consistency of melanoma risk assessment by two commercially available CNNs to help formulate recommendations for current clinical use. METHODS: A comparative cohort study was conducted from January to July 2022 at the Department of Dermatology, University Hospital Basel. Five dermoscopic images of 116 different lesions on the torso of 66 patients were captured consecutively by the same operator without deliberate rotation. Classification was performed by two CNNs (CNN-1/CNN-2). Lesions were divided into four subgroups based on their initial risk scoring and clinical dignity assessment. Reliability was assessed by variation and intraclass correlation coefficients. Excisions were performed for melanoma suspicion or two consecutively elevated CNN risk scores, and benign lesions were confirmed by expert consensus (n = 3). RESULTS: 117 repeated image series of 116 melanocytic lesions (2 melanomas, 16 dysplastic naevi, 29 naevi, 1 solar lentigo, 1 suspicious and 67 benign) were classified. CNN-1 demonstrated superior measurement repeatability for clinically benign lesions with an initial malignant risk score (mean variation coefficient (mvc): CNN-1: 49.5(±34.3)%; CNN-2: 71.4(±22.5)%; p = 0.03), while CNN-2 outperformed for clinically benign lesions with benign scoring (mvc: CNN-1: 49.7(±22.7)%; CNN-2: 23.8(±29.3)%; p = 0.002). Both systems exhibited lowest score consistency for lesions with an initial malignant risk score and benign assessment. In this context, averaging three initial risk scores achieved highest sensitivity of dignity assessment (CNN-1: 94%; CNN-2: 89%). Intraclass correlation coefficients indicated 'moderate'-to-'good' reliability for both systems (CNN-1: 0.80, 95% CI:0.71-0.87, p < 0.001; CNN-2: 0.67, 95% CI:0.55-0.77, p < 0.001). CONCLUSIONS: Potential user-induced image changes can significantly influence CNN classification. For clinical application, we recommend using the average of three initial risk scores. Furthermore, we advocate for CNN robustness optimization by cross-validation with repeated image sets. TRIAL REGISTRATION: ClinicalTrials.gov (NCT04605822).

Dietary phytate induces subclinical mechanical allodynia in mice.

Neuropathic pain is a condition with varying origins, including reduced dietary micronutrient intake. Phytate is a polyphosphate found in seeds and grains that can act as an antinutrient due to the ability of sequester essential divalent metals. Here we tested whether moderate dietary phytate intake could alter nociceptive pain. We subjected weaning mice to a chow supplemented with 1% phytate for eight weeks. Body weight gain, glycemic responses, food ingestion, water ingestion, and liver and adipose tissue weights were not altered compared to controls. We observed a decreased mechanical allodynia threshold in the intervention group, although there were no changes in heat- or cold-induced pain. Animals consuming phytate showed reduced spinal cord tumor necrosis factor (TNF), indicating altered inflammatory process. These data provide evidence for a subclinical induction of mechanical allodynia that is independent of phytate consumption in animals with otherwise normal phenotypic pattern.

Dietary phytate induces subclinical mechanical allodynia in mice

Neuropathic pain is a condition with varying origins, including reduced dietary micronutrient intake. Phytate is a polyphosphate found in seeds and grains that can act as an antinutrient due to the ability of sequester essential divalent metals. Here we tested whether moderate dietary phytate intake could alter nociceptive pain. We subjected weaning mice to a chow supplemented with 1% phytate for eight weeks. Body weight gain, glycemic responses, food ingestion, water ingestion, and liver and adipose tissue weights were not altered compared to controls. We observed a decreased mechanical allodynia threshold in the intervention group, although there were no changes in heat- or cold-induced pain. Animals consuming phytate showed reduced spinal cord tumor necrosis factor (TNF), indicating altered inflammatory process. These data provide evidence for a subclinical induction of mechanical allodynia that is independent of phytate consumption in animals with otherwise normal phenotypic pattern.

Double blind randomized clinical trial comparing minimally- invasive envelope flap and conventional envelope flap on impacted lower third molar surgery.

BACKGROUND: The latest trend in surgery is to look for minimally invasive procedures, with fewer complications and a shorter recovery time. This study aims to compare the minimally- invasive envelope flap, with smaller incision and fewer dissection and the conventional envelope flap, with a 20mm incision, on impacted mandibular third molar surgery, focusing on the hypothesis that there were no differences in postoperative outcomes. MATERIAL AND METHODS: A double-blind randomized clinical trial was designed to compare both incisions, focused on determining the approach with minor postoperative side-effects and minor impact on quality-of-life. A total of 60 patients were enrolled for the study if their presented impacted mandibular third molar and was 18-years-old or more. Both groups were evaluated from time elapsed on the surgery, maximum mouth opening, swelling and quality of life assessment. RESULTS: The flap choice influenced facial swelling (p=0,03), pain on the first three days (p=0,037), interference with oral hygiene (p=0,019) and discomfort on speech (p=0,07). Chewing, swallowing, trismus, pain after seven days, postoperative complications and other quality-of-life arrangements were no different between groups. CONCLUSIONS: The minimally- invasive envelope flap could lead to a less painful experience for the patient, with fewer impact on the oral hygiene and speech discomfort.

Multimorbidity prevalence and patterns and their associations with health literacy among chronic kidney disease patients.

BACKGROUND: Health literacy is the ability to deal with information related to one's health. Patients with low health literacy have poor disease-management skills for chronic diseases, such as chronic kidney disease (CKD). This could influence the number and combination of their diseases. METHODS: We included adult patients with CKD stages 1-5 from the Lifelines Study (n = 2,742). We assessed the association between low health literacy and the number and patterns of comorbidities, considering them globally and stratified by age and sex, using multinomial logistic regression and latent class analysis, respectively. RESULTS: Low health literacy was associated with a higher number of comorbidities in the crude models, and after adjustment for age, sex, eGFR, smoking, and BMI. In the crude model, the OR for low health literacy increased from 1.71 (1.25-2.33) for two comorbidities to 2.71 (2.00-3.68) for four comorbidities. In the fully-adjusted model, the associations remained significant with a maximum OR of 1.70 (1.16-2.49) for four comorbidities. The patterns of multimorbidity were similar for low and adequate health literacy, overall and by sex, bur tended to be different for patients older than 65. Older patients with low health literacy had higher comorbidity prevalence and a relatively greater share of cardiovascular, psychiatric, and central nervous system diseases. CONCLUSIONS: Among CKD patients, low health literacy is associated with more multimorbidity. Health literacy is not associated with patterns of multimorbidity in younger patients, but a difference was observed in older ones. Improving low health literacy could be an intervention efficient also in decreasing multimorbidity in CKD patients.

Cystic fibrosis drug trial design in the era of CFTR modulators associated with substantial clinical benefit: stakeholders' consensus view.

CFTR modulators associated with substantial clinical benefit are expected to rapidly improve the baseline condition of people with cystic fibrosis (PWCF) as well as decrease the rate of lung function decline, the occurrence of pulmonary exacerbations and likely even other disease complications. These changes in clinical status of PWCF introduced by clinically effective modulator therapy will have major repercussions on modalities of future CF drug development. As part of its 'Strategic Plan to speed up Access to new Drugs', the European Cystic Fibrosis Society (ECFS) convened a meeting in Brussels on November 27th 2019 with relevant stakeholders (CF researchers and clinicians, patient organization and pharmaceutical company representatives, regulators, health technology assessors; see Acknowledgments for list of attendees) to discuss the future of clinical trials in cystic fibrosis (CF) in the context of HEMT entering the clinical arena. The following is the conclusion of the presentations and discussions. It is hoped that these concepts will be considered in future regulatory guidelines and may provide rationale and support for alternative trial designs.

Lipid nanocarriers containing Passiflora edulis seeds oil intended for skin application.

Nanostructured lipid carriers (NLC) have been studied for over 20 years, constituting the second generation of lipid nanoparticles. These nanosystems were introduced to overcome the drawbacks of solid lipid nanoparticles (SLN). Passion fruit seeds oil have a high antioxidant potential and also skin whitening properties. The objectives of this work were to prepare NLC by two methods (ultrasonication and High pressure homogenization) using different solid lipids (Glyceryl Distearate, Glyceryl Dibehenate and Cetyl Palmitate) and passion fruit seeds oil as liquid lipid. The nanoparticles prepared with glyceryl distearate, using the ultrasonication method showed better characteristics, since these nanosystems presented smaller particle sizes and polydispersity index, and higher zeta potential. Besides that, these nanoparticles showed a high occlusion factor and non-irritant potential in HET-CAM assay. Based on the results obtained, it may be suggested that the prepared NLCs can be applied to the face, since they did not cause any irritation, and represent a potential strategy for further use in topical formulations with antioxidant activity.

A comparison between endoscopic and microscopic approaches for stapes surgery: a systematic review.

OBJECTIVES: To evaluate the surgical techniques, approaches, audiological outcomes and complications of endoscopic stapes surgery. METHODS: Systematic searches of the literature were performed in PubMed, Web of Science and Scopus databases, to identify studies of patients who underwent stapes surgery using endoscopic approaches and studies reporting objective post-operative hearing outcomes. The following information was extracted: surgery duration, complications, surgical technique and audiometric results. RESULTS: Fourteen studies were selected for appraisal, which included a total of 282 ears subjected to endoscopic stapes surgery. Endoscopic stapes surgery seems to provide adequate visualisation of the middle-ear structures, thereby allowing less invasive surgery and potentially equivalent audiological outcomes as compared with a traditional microscopic approach. Other advantages of endoscopic stapes surgery include decreased surgery time, a reduced need for drilling, and auditory results comparable to those of microscopic techniques. CONCLUSION: Studies have shown that endoscopic stapes surgery has similar surgical and functional advantages as compared with microscopic surgery.

Functionalizing nanoparticles with cancer-targeting antibodies: A comparison of strategies.

Standard cancer therapies sometimes fail to deliver chemotherapeutic drugs to tumor cells in a safe and effective manner. Nanotechnology takes the lead in providing new therapeutic options for cancer due to major potential for selective targeting and controlled drug release. Antibodies and antibody fragments are attracting much attention as a source of targeting ligands to bind specific receptors that are overexpressed on cancer cells. Therefore, researchers are devoting time and effort to develop targeting strategies based on nanoparticles functionalized with antibodies, which hold great promise to enhance therapeutic efficacy and circumvent severe side effects. Several methods have been described to immobilize antibodies on the surface of nanoparticles. However, selecting the most appropriate for each application is challenging but also imperative to preserve antigen binding ability and yield stable antibody-conjugated nanoparticles. From this perspective, we aim to provide considerable knowledge on the most widely used methods of functionalization that can be helpful for decision-making and design of conjugation protocols as well. This review summarizes adsorption, covalent conjugation (carbodiimide, maleimide and "click" chemistries) and biotin-avidin interaction, while discussing the advantages, limitations and relevant therapeutic approaches currently under investigation.

Bactérias zoonóticas isoladas de Passeriformes silvestres recuperados do tráfico de animais no estado do Ceará/Brasil / Zoonotic bacteria isolated from wild Passeriformes recovered from animal trafficking in the State of Ceará/Brazil

A ordem dos Passeriformes é uma das mais pressionadas pelas ações antrópicas, especialmente as relativas ao tráfico de animais, que, devido às más condições de manejo e higiênico-sanitárias, favorecem a infecção dos espécimes por patógenos virulentos e zoonóticos, como cepas de Escherichia coli e Salmonella spp., cujo isolamento em suabes cloacais, bem como a análise dos genes de virulência das cepas de E. coli foram objetivos do estudo. Para isso, 120 Passeriformes silvestres nativos, recebidos pelo Cetas/CE, foram avaliados individualmente. As cepas isoladas foram submetidas a teste de disco difusão para determinação da sensibilidade aos antimicrobianos. Em etapa posterior, foi realizada PCR para a detecção de oito genes de virulência dos principais patotipos diarreiogênicos de E. coli. Quanto aos resultados, nenhuma cepa de Salmonella spp. foi isolada, no entanto a ocorrência de E. coli foi de 40,8%. Foi observada elevada resistência, principalmente aos antimicrobianos tetraciclina, ampicilina e sulfazotrim, ocorrendo multirresistência em 42,8% das cepas. Pela análise molecular, foram diagnosticados quatro entre os nove genes pesquisados, com a identificação de EPEC típicas, EPEC atípicas, ETEC, EHEC e EAEC. Os resultados apontam para a importância de Passeriformes como possíveis disseminadores de zoonoses.(AU)

The order Passeriformes is one of the most pressured by anthropic actions, especially those related to animal trafficking. Due to poor sanitary and hygienic conditions, the infection of the specimens is favored by virulent and zoonotic pathogens such as strains of Escherichia coli and Salmonella spp., whose isolation in cloacal swabs as well as the analysis of the virulence genes of E. coli strains were the objectives of the study. For this, 120 native wild Passeriformes, received by CETAS/CE were individually evaluated. The isolated strains were submitted to diffusion disc test to determine sensitivity to antimicrobials. In a later stage, PCR was performed for the detection of eight virulence genes from the main E. coli diarrhoeagenic pathogens. Regarding the results, no strain of Salmonella spp. was isolated; however, the occurrence of E. coli was 40.8%. High resistance was observed, mainly to the antimicrobials Tetracycline, Ampicillin and Sulfazotrim, with multi-resistance in 42.8% of the strains. By molecular analysis, four of the nine genes were diagnosed, identifying typical EPEC, atypical EPEC, ETEC, EHEC and EAEC. The results point to the importance of Passeriformes as possible disseminators of zoonoses.(AU)

Credentialing for robotic lobectomy: what is the learning curve? A retrospective analysis of 272 consecutive cases by a single surgeon.

Credentialing processes for surgeons seeking robotic thoracic surgical privileges are not evidence-based, and the learning curve has not been reported. The goal of this study is to review our experience with robotic lobectomies and provide evidence for the development of a more uniform credentialing process. We performed a retrospective review of the first 272 consecutive robotic lobectomies performed between 2011 and 2017 by a single surgeon with prior video-assisted thoracoscopic (VATS) experience. Primary outcomes were operative duration, blood loss, chest tube duration, length of hospital stay, intraoperative complication, and conversion to thoracotomy. The patients were subdivided by surgical date into two cohorts of 120 consecutive patients to compare differences in outcomes, thereby illustrating the learning curve. Between 2011 and 2017, 272 patients (median age 67.5 years) underwent a robotic lobectomy by a single surgeon. The majority of patients (157/272) had early stage (T1N0) adenocarcinoma. For the entire cohort, median operative time was 160 min (83-317 min). The median blood loss was 75 mL (10-4000 mL). Median chest tube duration was 2 days (1-23 days) and median hospital stay was 3 days (1-25 days). Intraoperative complications occurred in seven patients. Only six patients required conversion to thoracotomy. Using multivariable logistic regression, it was found that the age, gender, and stage do not factor into conversion to thoracotomy, but BMI was found to be a significant covariate (p 0.043). As the surgeon performs more surgeries, there is a significantly shorter operative time (p < 0.001), decreased blood loss (p < 0.001), and shorter hospital stay (p < 0.014). When the first 120 and last 120 surgeries were compared, there was significantly less blood loss (234.6 vs 78.69 cc, p < 0.001), shorter operative time (181.9 vs 147.4 min, p < 0.001), shorter tube duration (3.49 vs 3.11 days, p 0.007), and shorter length of stay (4.03 vs 3.48 days, p < 0.001), respectively. More intraoperative complications were observed during the first 120 surgeries (6/120) compared to the last 120 surgeries (0/120; Fischer exact p = 0.029). Regression model plots did not show any apparent and significant change points, but rather a steady improvement. The more cases the surgeon does, the better is the outcome in terms of operative duration, blood loss, post-operative length of stay and intraoperative complications. The learning curve for robotic surgery for a surgeon with prior VATS experience is that of a continuous improvement with experience instead of a particular change point. Since most thoracic surgeons who perform robotic-assisted surgery have already gotten past their VATS learning curves, they no longer have a definable learning curve for robotic surgery. Hence, if a surgeon is already proficient and credentialed to perform VATS lung resections, he or she is no longer faced with a significant learning curve for robotic lung resections, and should be credentialed to do so once he or she has undergone the appropriate training with the equipment and technology.

Intestinal cell migration damage induced by enteropathogenic Escherichia coli strains.

Epithelial cell migration is an essential response to enteric pathogens such as enteropathogenic Escherichia coli (EPEC). This study aimed to investigate the effects of EPEC infection on intestinal epithelial cell migration in vitro, as well as the involvement of type III secretion system (T3SS) and Rho GTPases. Crypt intestinal epithelial cells (IEC-6) were infected with EPEC strains (E2348/69, ΔescF, and the LDI001 strain isolated from a malnourished Brazilian child) and commensal E. coli HS. Wound migration and cell death assays were performed at different time-points. Transcription and expression of Rho GTPases were evaluated using real-time PCR and western blotting. Overall, EPEC E2348/69 reduced migration and increased apoptosis and necrosis levels compared to EPEC LDI001 and E. coli HS strains. Moreover, EPEC LDI001 impaired cell migration at a higher level than E. coli HS and increased necrosis after 24 hours compared to the control group. The different profiles of virulence genes between the two wild-type EPEC strains, characterized by the absence of espL and nleE genes in the LDI001, might explain the phenotypic results, playing significant roles on cell migration impairment and cell death-related events. Moreover, the type III secretion system is determinant for the inhibition of intestinal epithelial cell migration by EPEC 2348/69, as its deletion prevented the effect. Active Rac1 concentrations were increased in E2348/69 and LDI001-infected cells, while the T3SS-deficient strain did not demonstrate this activation. This study contributes with valuable insight to characterize the mechanisms involved in the impairment of intestinal cell migration induced by EPEC.

Effectiveness and safety of foam sclerotherapy with 5% ethanolamine oleate in the treatment of low-flow venous malformations in the head and neck region: a case series.

The aim of this study was to evaluate the effectiveness and safety of 5% ethanolamine oleate (EO) foam in the treatment of low-flow venous malformations in the head and neck region. Seventeen consecutive patients (six male, 11 female) and 34 low-flow venous malformations were enrolled. The vascular anomalies ranged between 20mm and 80mm in size. The typical clinical indication was a swelling (88.2%) with a purple colour (85.3%); the most frequent location was the tongue (23.5%). Ethanolamine oleate foam was produced via the Tessari method and applied at 10mg per 1cm to the vascular anomalies. This process resulted in the highest clinical healing score in 64.7% of cases, and half of the patients reported a high level of satisfaction (score >9). In the majority of cases (88.2%), the patients reported that the pain immediately postoperative was mild or moderate. There were direct relationships between vascular anomaly size and the volume of EO applied, the number of sessions, and healing (P<0.05). No recurrence was observed during 6 months of follow-up. This case series showed the effectiveness and safety of 5% EO foam for the treatment of venous malformations in the head and neck region.

Acaricidal activity of essential oil of Syzygium aromaticum, hydrolate and eugenol formulated or free on larvae and engorged females of Rhipicephalus microplus.

The cattle tick, Rhipicephalus microplus (Canestrini, 1888) (Ixodida: Ixodidae), is the most important ectoparasite in cattle-breeding areas and is responsible for severe economic losses. Synthetic acaricides have been used to control this parasite. However, the need for safer products has stimulated the search for new acaricides, such as those to be obtained from medicinal plants. The essential oil of Syzygium aromaticum (clove) has many biological properties and shows great potential for use in veterinary applications. In the context of the need for new agents, this study investigated the in vitro properties of the hydrolate, essential oil and the main constituent of S. aromaticum, eugenol, in formulated and free applications against larvae and females of R. microplus. Eugenol and the essential oil caused 100% mortality in larvae at starting applications of 2.5 mg/mL and 5.0 mg/mL, respectively. The hydrolate showed no activity. Both eugenol and essential oil had good efficacy in adult immersion tests at 50 mg/mL and achieved 100% efficacy at a concentration of 100 mg/mL. The results of these tests reaffirm the important potential of clove essential oil and eugenol.

Intestinal cell migration damage induced by enteropathogenic Escherichia coli strains

Epithelial cell migration is an essential response to enteric pathogens such as enteropathogenic Escherichia coli (EPEC). This study aimed to investigate the effects of EPEC infection on intestinal epithelial cell migration in vitro, as well as the involvement of type III secretion system (T3SS) and Rho GTPases. Crypt intestinal epithelial cells (IEC-6) were infected with EPEC strains (E2348/69, ΔescF, and the LDI001 strain isolated from a malnourished Brazilian child) and commensal E. coli HS. Wound migration and cell death assays were performed at different time-points. Transcription and expression of Rho GTPases were evaluated using real-time PCR and western blotting. Overall, EPEC E2348/69 reduced migration and increased apoptosis and necrosis levels compared to EPEC LDI001 and E. coli HS strains. Moreover, EPEC LDI001 impaired cell migration at a higher level than E. coli HS and increased necrosis after 24 hours compared to the control group. The different profiles of virulence genes between the two wild-type EPEC strains, characterized by the absence of espL and nleE genes in the LDI001, might explain the phenotypic results, playing significant roles on cell migration impairment and cell death-related events. Moreover, the type III secretion system is determinant for the inhibition of intestinal epithelial cell migration by EPEC 2348/69, as its deletion prevented the effect. Active Rac1 concentrations were increased in E2348/69 and LDI001-infected cells, while the T3SS-deficient strain did not demonstrate this activation. This study contributes with valuable insight to characterize the mechanisms involved in the impairment of intestinal cell migration induced by EPEC.

mRNA-based detection of rare CFTR mutations improves genetic diagnosis of cystic fibrosis in populations with high genetic heterogeneity.

Even with advent of next generation sequencing complete sequencing of large disease-associated genes and intronic regions is economically not feasible. This is the case of cystic fibrosis transmembrane conductance regulator (CFTR), the gene responsible for cystic fibrosis (CF). Yet, to confirm a CF diagnosis, proof of CFTR dysfunction needs to be obtained, namely by the identification of two disease-causing mutations. Moreover, with the advent of mutation-based therapies, genotyping is an essential tool for CF disease management. There is, however, still an unmet need to genotype CF patients by fast, comprehensive and cost-effective approaches, especially in populations with high genetic heterogeneity (and low p.F508del incidence), where CF is now emerging with new diagnosis dilemmas (Brazil, Asia, etc). Herein, we report an innovative mRNA-based approach to identify CFTR mutations in the complete coding and intronic regions. We applied this protocol to genotype individuals with a suspicion of CF and only one or no CFTR mutations identified by routine methods. It successfully detected multiple intronic mutations unlikely to be detected by CFTR exon sequencing. We conclude that this is a rapid, robust and inexpensive method to detect any CFTR coding/intronic mutation (including rare ones) that can be easily used either as primary approach or after routine DNA analysis.

Therapeutic Strategies for Alzheimer's and Parkinson's Diseases by Means of Drug Delivery Systems.

Alzheimer's and Parkinson's diseases are prevalent neurodegenerative disorders worldwide, which are essentially related to aging. Within the remarkable era of nanomedicine, nowadays several delivery systems have been suggested to improve the treatment of these disorders, namely, liposomes, micelles, nanoparticles (polymeric, lipid, metallic and inorganic), exosomes, dendrimers and fullerenes. The advantage that has been claimed to these delivery systems is that they facilitate the passage of drugs through the blood brain barrier (BBB), enabling targeting before body degradation, and increasing therapeutic efficacy, comparied to conventional pharmaceutical dosage forms. This review article provides a state of the art regarding the drug delivery systems that have been studied for the treatment of Alzheimer's and Parkinson's diseases. It begins with a brief description of the central nervous system (CNS) and the mechanisms involved in the development of these diseases. Later, some examples of drugs used in the treatment of these neurodegenerative diseases are presented, which are currently available in conventional pharmaceutical dosage forms, and in new drug delivery systems that are under development.

Enzymatic regulation of seasonal glycogen cycling in the freeze-tolerant wood frog, Rana sylvatica.

Liver glycogen is an important energy store in vertebrates, and in the freeze-tolerant wood frog, Rana sylvatica, this carbohydrate also serves as a major source of the cryoprotectant glucose. We investigated how variation in the levels of the catalytic subunit of protein kinase A (PKAc), glycogen phosphorylase (GP), and glycogen synthase (GS) relates to seasonal glycogen cycling in a temperate (Ohioan) and subarctic (Alaskan) populations of this species. In spring, Ohioan frogs had reduced potential for glycogen synthesis, as evidenced by low GS activity and high PKAc protein levels. In addition, glycogen levels in spring were the lowest of four seasonal samples, as energy input was likely directed towards metabolism and somatic growth during this period. Near-maximal glycogen levels were reached by mid-summer, and remained unchanged in fall and winter, suggesting that glycogenesis was curtailed during this period. Ohioan frogs had a high potential for glycogenolysis and glycogenesis in winter, as evidenced by large glycogen reserves, high levels of GP and GS proteins, and high GS activity, which likely allows for rapid mobilization of cryoprotectant during freezing and replenishing of glycogen reserves during thawing. Alaskan frogs also achieved a near-maximal liver glycogen concentration by summer and displayed high glycogenic and glycogenolytic potential in winter, but, unlike Ohioan frogs, started replenishing their energy reserves early in spring. We conclude that variation in levels of both glycogenolytic and glycogenic enzymes likely happens in response to seasonal changes in energetic strategies and demands, with winter survival being a key component to understanding the regulation of glycogen cycling in this species.

Scaffolds for Bone Regeneration: State of the Art.

Nowadays, millions of people worldwide are affected by problems of bones and articulations. These conditions represent about a half of the chronic diseases developed in individuals over 50 years, leading to problems of prolonged pain and physical inability, which usually require surgery, where bone grafts or implants are used. Nonetheless, despite the success of these therapeutic solutions, some drawbacks have been pointed out, related with the risk of developing infections after implant application within the body. Moreover, grafts are associated to pain, infection, tissue death at the donor site and immunological rejection. To overcome these limitations, tissue engineering has an important role that constitutes a promising area for repair and rebuild bone lesions, through the development of three-dimensional (3D) porous matrices, commonly known as scaffolds. Associated with these structures are mesenchymal stem cells and growth factors, which lead to the formation of new bone by stimulating the natural regeneration ability of the patient's tissue. In this review, we address the most important methodologies and concepts regarding tissue engineering for the replacement of bone tissue. The concept of scaffold, and examples of different types of scaffolds and their respective production methods are presented. In vitro and in vivo techniques to evaluate the suitability of scaffolds for human use are discussed. In addition, some of the most recent studies regarding the application of scaffolds for bone tissue engineering are described.

Dioxins, furans, biphenyls, arsenic, thorium and uranium in natural and anthropogenic sources of phosphorus and calcium used in agriculture.

The aim of this study was to assess the presence of dioxins, furans and biphenyls, and the inorganic contaminants such as arsenic (As), thorium (Th) and uranium (U) in three main products used in Agriculture in Brazil: feed grade dicalcium phosphate, calcined bovine bone meal and calcitic limestone. The first two are anthropogenic sources of phosphorus and calcium, while calcitic limestone is a natural unprocessed mineral. Regarding to dioxin-like substances, all samples analyzed exhibited dioxins (PCDD) and furans (PCDF) and dioxin-like polychlorinated biphenyls (dl-PCBs) concentrations below limit of detection (LOD). In general, achieved is in accordance with regulation in Brazil where is established a maximum limit in limestone used in the citric pulp production (0.50pg WHO-TEQ g(-1)). In addition, reported data revealed very low levels for limestone in comparison with similar materials reported by European legislation. As result for toxic metals, achieved data were obtained using Instrumental Neutron Activation Analysis (INAA). On one hand, limestone sample exhibits the largest arsenic concentration. On another hand, dicalcium phosphate exhibited the largest uranium concentration, which represents a standard in animal nutrition. Therefore, it is phosphorus source in the animal feed industry can be a goal of concern in the feed field.