Mass extinction in poorly known taxa

Since the 1980s, many have suggested we are in the midst of a massive extinction crisis, yet only 799 (0.04%) of the 1.9 million known recent species are recorded as extinct, questioning the reality of the crisis. This low figure is due to the fact that the status of very few invertebrates, which represent the bulk of biodiversity, have been evaluated. Here we show, based on extrapolation from a random sample of land snail species via two independent approaches, that we may already have lost 7% (130,000 extinctions) of the species on Earth. However, this loss is masked by the emphasis on terrestrial vertebrates, the target of most conservation actions. Projections of species extinction rates are controversial because invertebrates are essentially excluded from these scenarios. Invertebrates can and must be assessed if we are to obtain a more realistic picture of the sixth extinction crisis.     

Effects of a continuous-combined regimen of low-dose hormone therapy (oestradiol and norethindrone acetate) and tibolone on the quality of life in symptomatic postmenopausal women: A double-blind,randomised study

ObjectiveThis study compared the effects of a continuous-combined regimen of low-dose hormone therapy (LD-HT) versus tibolone and supplemental calcium/vitamin D3 (control) on quality of life (QoL) in symptomatic postmenopausal women.DesignThis study was a prospective, randomised, double-blind, comparative trial with a control group.SettingThe study was conducted in a climacteric outpatient clinic in the University Hospital of Federal University of Juiz de Fora, Brazil.PopulationA total of 174 postmenopausal women under 60 years of age who attended the climacteric outpatient clinic between June 2009 and June 2011 were recruited. These women complained of moderate or intense vasomotor symptoms and exhibited no contraindications for the use of hormone therapy.InterventionsThe patients were randomised into three groups: (1) daily treatment with 2.5 mg tibolone (n = 64), (2) 50 mg calcium carbonate + 200 IU vitamin D3 (Ca/Vit D3, n = 54) or (3) 1 mg oestradiol + 0.5 mg norethindrone acetate (E2/NETA, n = 56) for 12 weeks.Primary outcome measuresThe primary outcome was the evaluation of QoL using the Women's Health Questionnaire (WHQ) in all subjects at baseline and after 4, 8 and 12 weeks of treatment.ResultsA total of 130 women in the following groups completed the study: tibolone (n = 42), Ca/Vit D3 (n = 44) and E2/NETA (n = 44). An improved QoL based on the WHQ was observed at T0 (80.12 ± 14.04, 77.73 ± 15.3, 77.45 ± 15.4) and T12 (57.0 ± 15.5, 55.7 ± 16.7, 58.4 ± 12.6) for the tibolone, E2 + NETA and Ca/Vit D3 groups, respectively (p values <0.05). The three groups exhibited significantly different scores at T12 for sexual behaviour and vasomotor symptoms. The tibolone group exhibited better sexual function compared with the E2/NETA and Ca/Vit D3 groups (4.2 ± 26, 5.6 ± 2.8, 5.4 ± 2.8, respectively, p values <0.05). LD-HT was superior to tibolone and Ca/Vit D3 treatment for improvements in vasomotor symptoms (3.2 ± 1.5, 4.0 ± 1.8, 4.3 ± 2.0, respectively, p values <0.05). Adverse effects were few and mild.ConclusionsAn improved QoL was observed in the three study groups. Tibolone primarily improved sexual function, and E2/NETA exhibited a superior response for vasomotor symptoms.     

Cell viability and hemocompatibility evaluation of a starch-based hydrogel loaded with hydroxyapatite or calcium carbonate for maxillofacial bone regeneration

The objective of this study is to evaluate the cell viability and hemocompatibility of starch-based hydrogels for maxillofacial bone regeneration. Seven starch-based hydrogels were prepared: three loaded with 0.5, 1 and 2% calcium carbonate (Sigma Aldrich, St. Louis, MO, USA); three loaded with 2, 3 and 4% hydroxyapatite (Sigma Aldrich); and one not loaded as a control. A 10 M NaOH was then added to induce hydrogel formation. Human osteoblasts were cultured on each hydrogel for 72 h. An MTS assay (Cell Titer96; PROMEGA, Madison, WI, USA) was used to assess cell viability. Hemocompatibility testing was conducted with normal human blood in the following conditions: 100 mg of each hydrogel in contact with 900 µL of whole blood for 15 min at 37 °C under lateral stirring. Higher percentages of cell viability were observed in starch-based hydrogels loaded with hydroxyapatite as compared with the control. The hemolysis test showed a hemolysis level lower than 2%. Activated partial thromboplastin time and prothrombin time were unchanged, while platelet counting showed a slight decrease when compared with controls.     

The favorable impact of PIK3CA mutations on survival: an analysis of 2587 patients with breast cancer

The phosphatidylinositol-3 kinase(PI3K) pathway regulates a number of cellular processes, including cell survival, cell growth, and cell cycle progression. Consequently, this pathway is commonly deregulated in cancer. In particular, mutations in the gene PIK3CA that encodes the p110α catalytic subunit of the PI3K enzymes result in cell proliferation and resistance to apoptosis in vitro and induce breast tumors in transgenic mice. These data underscore the role of this pathway during oncogenesis. Thus, an ongoing, large-scale effort is underway to develop clinically active drugs that target elements of the PI3K pathway. However, conflicting data suggest that gain-of-function PIK3CA mutations may be associated with either a favorable or a poor clinical outcome, compared with the wild-type PIK3CA gene. In the current study, we performed a systematic review of breast cancer clinical studies. Upon evaluation of 2587 breast cancer cases from 12 independent studies, we showed that patients with tumors harboring a PIK3CA mutation have a better clinical outcome than those with a wild-type PIK3CA gene. Importantly, this improved prognosis may pertain only to patients with mutations in the kinase domain of p110α and to postmenopausal women with estrogen receptor-positive breast cancer. We propose three potential explanations for this paradoxical observation. First, PIK3CA mutations may interfere with the metastasis process or may induce senescence, which results in a better outcome for patients with mutated tumors. Secondly, we speculate that PIK3CA mutations may increase early tumor diagnosis by modification of the actin cytoskeleton in tumor cells. Lastly, we propose that PIK3CA mutations may be a favorable predictive factor for response to hormonal therapy, giving a therapeutic advantage to these patients. Ultimately, an improved understanding of the clinical impact of PIK3CA mutations is critical for the development of optimally personalized therapeutics against breast cancer and other solid tumors. This effort will be important to prevent or explain therapeutic failures and select patients who are most likely to respond to new therapies that inhibit the PI3K pathway.     

Selective detection of bacterial layers with terahertz plasmonic antennas

Current detection and identification of micro-organisms is based on either rather unspecific rapid microscopy or on more accurate but complex and time-consuming procedures. In a medical context, the determination of the bacteria Gram type is of significant interest. The diagnostic of microbial infection often requires the identification of the microbiological agent responsible for the infection, or at least the identification of its family (Gram type), in a matter of minutes. In this work, we propose to use terahertz frequency range antennas for the enhanced selective detection of bacteria types. Several microorganisms are investigated by terahertz time-domain spectroscopy: a fast, contactless and damage-free investigation method to gain information on the presence and the nature of the microorganisms. We demonstrate that plasmonic antennas enhance the detection sensitivity for bacterial layers and allow the selective recognition of the Gram type of the bacteria.OCIS codes: (250.5403) Plasmonics, (300.6495) Spectroscopy, terahertz, (310.6188) Spectral properties, (170.1420) Biology     

Bilateral vertical complicated fracture of mandibular first primary molars associated with trauma: Report of an unusual case

Oral and maxillofacial injuries occur frequently during the primary and mixed dentitions, although vertical, complicated fractures involving the crown and root of primary molars are rarely observed during early childhood. Treatment of this type of fracture can be complex, requiring both an early, accurate diagnosis and a precise treatment plan. The purpose of this report was to describe the management of bilateral vertical complicated fracture of mandibular primary first molars associated with trauma in a 2-year-9-monthold girl.     

Prevalence of overweight and obesity in the adult indigenous population in Brazil: A systematic review with meta-analysis

To carry out a systematic review to identify the prevalence of overweight and obesity in the adult indigenous population in Brazil. The databases used were PubMed, Scopus, Virtual Health Library (VHL), and Science Direct, with the following search strategy: “overweight” OR “obesity” AND “indigenous” OR “tribe” AND “Brazil”. For the meta-analysis, RStudio^® software was used. Were 22 articles included. The combined effect of the meta-analysis studies showed a global prevalence of overweight and obesity of 45%. Approximately half (45%) of indigenous Brazilian adults have excess weight. These findings highlight the need to implement public policies for the prevention and treatment of these morbidities.     

Extreme Learning Machines for VISualization+R: Mastering Visualization with Target Variables

The current paper presents an improvement of the Extreme Learning Machines for VISualization (ELMVIS+) nonlinear dimensionality reduction method. In this improved method, called ELMVIS+R, it is proposed to apply the originally unsupervised ELMVIS+ method for the regression problems, using target values to improve visualization results. It has been shown in previous work that the approach of adding supervised component for classification problems indeed allows to obtain better visualization results. To verify this assumption for regression problems, a set of experiments on several different datasets was performed. The newly proposed method was compared to the ELMVIS+ method and, in most cases, outperformed the original algorithm. Results, presented in this article, prove the general idea that using supervised components (target values) with nonlinear dimensionality reduction method like ELMVIS+ can improve both visual properties and overall accuracy.     

Time-dependent lymphocyte count after transplantation is associated with higher risk of graft failure and death

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