Dental pulp pluripotent-like stem cells (DPPSC), a new stem cell population with chromosomal stability and osteogenic capacity for biomaterials evaluation

Background: Biomaterials are widely used to regenerate or substitute bone tissue. In order to evaluate their potential use for clinical applications, these need to be tested and evaluated in vitro with cell culture models. Frequently, immortalized osteoblastic cell lines are used in these studies. However, their uncontrolled proliferation rate, phenotypic changes or aberrations in mitotic processes limits their use in long-term investigations. Recently, we described a new pluripotent-like subpopulation of dental pulp stem cells derived from the third molars (DPPSC) that shows genetic stability and shares some pluripotent characteristics with embryonic stem cells. In this study we aim to describe the use of DPPSC to test biomaterials, since we believe that the biomaterial cues will be more critical in order to enhance the differentiation of pluripotent stem cells. Methods: The capacity of DPPSC to differentiate into osteogenic lineage was compared with human sarcoma osteogenic cell line (SAOS-2). Collagen and titanium were used to assess the cell behavior in commonly used biomaterials. The analyses were performed by flow cytometry, alkaline phosphatase and mineralization stains, RT-PCR, immunohistochemistry, scanning electron microscopy, Western blot and enzymatic activity. Moreover, the genetic stability was evaluated and compared before and after differentiation by short-comparative genomic hybridization (sCGH). Results: DPPSC showed excellent differentiation into osteogenic lineages expressing bone-related markers similar to SAOS-2. When cells were cultured on biomaterials, DPPSC showed higher initial adhesion levels. Nevertheless, their osteogenic differentiation showed similar trend among both cell types. Interestingly, only DPPSC maintained a normal chromosomal dosage before and after differentiation on 2D monolayer and on biomaterials. Conclusions: Taken together, these results promote the use of DPPSC as a new pluripotent-like cell model to evaluate the biocompatibility and the differentiation capacity of biomaterials used in bone regeneration

An Analysis on the Efficiency of Philippine Microfinance Institutions: A Stochastic Frontier Approach

Microfinance institutions (MFIs) were created to provide loans and financial services for the poor as commercial banks have requirements that are not accessible to them. The Philippines government soon started using MFIs as a poverty alleviation tool to answer the market failure created by the commercial banking industry since it cannot accommodate the needs of low-income earners due to the high costs attached to it. However, recent studies have shown that MFIs are “mission drifting,” which means that they are deviating from their original social purpose and becoming more financially driven. As a result, this paper estimates the financial and social efficiency of Philippine MFIs using a two-step Stochastic Frontier Approach from 2005 to 2018

Psychological Capital of Spanish Workers: Confirmatory Factor Analysis of PCQ-12

Background: The concept of positive psychological capital draws from the study of positive organizational behavior and refers to a psychological state characterized by self-efficacy, hope, resilience, and optimism that can be developed and related to job performance. Methods: This paper analyzed the reliability and factorial structure of the Psychological Capital Questionnaire-12 (PCQ-12) in a sample composed by Spanish workers (N = 339), from different professional sectors, through a confirmatory factor analysis (CFA). Results: The analysis assessed a model with four-correlated factors competing with a second-order model proposed by the authors of this instrument. The results of the adjustment and reliability values of the dimensions are discussed in light of various studies which differ from our model or support it along with its limitations and contributes. Conclusion: Our results indicate the need to contemplate this instrument's sensitivity towards cultural differences, both geographical and organizational

Experimental and Theoretical Investigation of Multispecies Oral Biofilm Resistance to Chlorhexidine Treatment

We investigate recovery of multispecies oral biofilms following chlorhexidine gluconate (CHX) and CHX with surface modifiers (CHX-Plus) treatment. Specifically, we examine the percentage of viable bacteria in the biofilms following their exposure to CHX and CHX-Plus for 1, 3, and 10 minutes, respectively. Before antimicrobial treatment, the biofilms are allowed to grow for three weeks. We find that (a). CHX-Plus kills bacteria in biofilms more effectively than the regular 2% CHX does, (b). cell continues to be killed for up to one week after exposure to the CHX solutions, (c). the biofilms start to recover after two weeks, the percentage of the viable bacteria recovers in the 1 and 3 minutes treatment groups but not in the 10 minutes treatment group after five weeks, and the biofilms fully return to the pretreatment levels after eight weeks. To understand the mechanism, a mathematical model for multiple bacterial phenotypes is developed, adopting the notion that bacterial persisters exist in the biofilms together with regulatory quorum sensing molecules and growth factor proteins. The model reveals the crucial role played by the persisters, quorum sensing molecules, and growth factors in biofilm recovery, accurately predicting the viable bacterial population after CHX treatment.Fundación Obra Social de La CaixaFundación CanadáFundación Ramón Areces (Postdoctoral Scholarship

Septal projections to the nucleus incertus in the rat: Bidirectional pathways for modulation of hippocampal function

Projections from the nucleus incertus (NI) to the septum have been implicated in the modulation of hippocampal theta rhythm. In this study we describe a previously uncharacterized projection from the septum to the NI, which may provide feedback modulation of the ascending circuitry. Fluorogold injections into the NI resulted in retrograde labeling in the septum that was concentrated in the horizontal diagonal band and areas of the posterior septum including the septofimbrial and triangular septal nuclei. Double-immunofluorescent staining indicated that the majority of NI-projecting septal neurons were calretinin-positive and some were parvalbumin-, calbindin-, or glutamic acid decarboxylase (GAD)−67-positive. Choline acetyltransferase-positive neurons were Fluorogold-negative. Injection of anterograde tracers into medial septum, or triangular septal and septofimbrial nuclei, revealed fibers descending to the supramammillary nucleus, median raphe, and the NI. These anterogradely labeled varicosities displayed synaptophysin immunoreactivity, indicating septal inputs form synapses on NI neurons. Anterograde tracer also colocalized with GAD-67-positive puncta in labeled fibers, which in some cases made close synaptic contact with GAD-67-labeled NI neurons. These data provide evidence for the existence of an inhibitory descending projection from medial and posterior septum to the NI that provides a "feedback loop" to modulate the comparatively more dense ascending NI projections to medial septum and hippocampus. Neural processes and associated behaviors activated or modulated by changes in hippocampal theta rhythm may depend on reciprocal connections between ascending and descending pathways rather than on unidirectional regulation via the medial septum.Grant sponsors: Fundación Alicia Koplowitz Fellowship (to A.M.S.P.), CAPES-Brasil Bex - 4494/09-1 (to F.N.S.) and 4496/09-4 (to C.W.P.) and Fapitec edital #01/08 (to F.N.S.), FIS-isciiiPI10/01399 (to J.S.), National Health and Medical Research Council of Australia - 520299 (to S.M.), 509246, 1005985, and 1005988 (to A.L.G.), the Florey Foundation (to S.M., A.L.G.), Besen Family Foundation (to A.L.G.) and a NEUREN project, FP7-PEOPLE-IRSES PIRSES-GA-2012-318997 (to A.L.G., F.E.O.-B.)

Broadening the perspective of zero-deforestation interventions in Peru by incorporating concepts from the global value chain literature

Global narratives around the links between deforestation and agricultural commodity production have led to the application of voluntary zero-deforestation agreements between companies, governments, and civil society. The continued tropical deforestation warrants a re-examination of this approach in order to customize its application for a particular location. Our paper contributes to this by exploring the spatial associations between deforestation and the production of cacao, coffee, and oil palm in the Amazon region in Peru. The geographical overlaps between deforestation, and the distribution of these commodity crops, indicate four types of spatial associations: (1) a high degree of deforestation and a high degree of commodity production (high-high); (2) a high degree of deforestation and a low degree of commodity production (high-low); (3) a low degree of deforestation and a high degree of commodity production (low-high); and (4) a low degree of deforestation and a low degree of commodity production (low-low). On the basis of these associations, we present four scenarios in which zero-deforestation supply chain interventions may operate in Peru and argue that broadening the perspective of such interventions by adopting a global value chain lens can improve the use of previously deforested lands, prevent unintended or future deforestation and, in turn, ensure that no forest area is left behind

Specific allergen immunotherapy for the treatment of atopic eczema: a Cochrane systematic review

Background Specific allergen immunotherapy (SIT) is an effective allergy treatment, but it is unclear whether SIT is effective for atopic eczema (AE). We undertook a systematic review to assess SIT efficacy and safety for treating AE. Methods We searched databases, ongoing clinical trials registers, and conference proceedings up to July 2015. Randomized controlled trials (RCTs) of SIT using standardized allergen extracts, compared with placebo/control, for treating AE in patients with allergic sensitization were eligible. Results We identified 12 eligible trials with 733 participants. Interventions included subcutaneous (six trials), sublingual (four trials), oral or intradermal SIT in children/adults allergic to house dust mite (10 trials), grass pollen or other inhalants. Risk of bias was moderate, with high loss to follow‐up and nonblinding as the main concerns. For our primary outcomes, three studies (208 participants) reported no significant difference – patient‐reported global disease severity improvement RR 0.75 (95% CI 0.45, 1.26); and eczema symptoms mean difference −0.74 on a 20‐point scale (95% CI −1.98, 0.50). Two studies (85 participants) reported a significant difference – SIT improved global disease severity RR 2.85 (95% CI 1.02, 7.96); and itch mean difference −4.20 on a 10‐point scale (95% CI −3.69, −4.71). Meta‐analysis was limited due to extreme statistical heterogeneity. For some secondary outcomes, meta‐analyses showed benefits for SIT, for example investigator‐rated improvement in eczema severity RR 1.48 (95% CI 1.16, 1.88; six trials, 262 participants). We found no evidence of adverse effects. The overall quality of evidence was low. Conclusion We found no consistent evidence that SIT is effective for treating AE, but due to the low quality of evidence further research is needed to establish whether SIT has a role in AE treatment

Toward zero-deforestation value chains: Environmental upgrading and downgrading among non-certified cocoa producers in Colombia

Global pressure to make value chains less damaging to the natural environment, a process known as environment upgrading, has been building in recent years. Most studies that assess environmental upgrading have focused on the compliance of suppliers, which would be farmers in the case of value chains involving agrifood commodities, to sustainability certification standards. Our case study focusing on cocoa producers in Colombia explores an under-investigated topic in environmental upgrading — that of whether sustainable practices of non-certified farmers facilitate zero-deforestation value chains. Using data from 930 randomly sampled households in the Colombian departments of Caqueta and Cesar, we examined the association of non-certified sustainable practices, i.e., processes that benefit the environment which farmers undertake on their own and not because of adherence to sustainability certification criteria, with reforestation and deforestation: A positive association of the practices with the former suggests environmental upgrading, while with the latter would be environmental downgrading, which denotes negative environmental outcomes from the process of environmental upgrading. We also assessed whether or not there are significant differences between mean deforestation and reforestation rates between certified and non-certified cocoa producers in both departments. Based on statistical tests, we found that (a) non-certified sustainable practices can facilitate environmental upgrading and discourage environmental downgrading but only in some cases, and (b) there is no significant difference in mean deforestation rates between certified and non-certified surveyed cocoa producers, but there is a significant difference in mean reforestation rates between the two groups of producers. These results suggest that implementing non-certified sustainable practices poses another way to enable value chain actors to meet the requirements in markets seeking sustainably produced commodities. One such market is that of the European Union, whose legislation on deforestation-free commodities makes certification an optional rather than compulsory process to support the prescribed procedure on diligence procedure

Diminution of Voltage Threshold Plays a Key Role in Determining Recruitment of Oculomotor Nucleus Motoneurons during Postnatal Development

The size principle dictates the orderly recruitment of motoneurons (Mns). This principle assumes that Mns of different sizes have a similar voltage threshold, cell size being the crucial property in determining neuronal recruitment. Thus, smaller neurons have higher membrane resistance and require a lower depolarizing current to reach spike threshold. However, the cell size contribution to recruitment in Mns during postnatal development remains unknown. To investigate this subject, rat oculomotor nucleus Mns were intracellularly labeled and their electrophysiological properties recorded in a brain slice preparation. Mns were divided into 2 age groups: neonatal (1–7 postnatal days, n = 14) and adult (20–30 postnatal days, n = 10). The increase in size of Mns led to a decrease in input resistance with a strong linear relationship in both age groups. A well-fitted inverse correlation was also found between input resistance and rheobase in both age groups. However, input resistance versus rheobase did not correlate when data from neonatal and adult Mns were combined in a single group. This lack of correlation is due to the fact that decrease in input resistance of developing Mns did not lead to an increase in rheobase. Indeed, a diminution in rheobase was found, and it was accompanied by an unexpected decrease in voltage threshold. Additionally, the decrease in rheobase co-varied with decrease in voltage threshold in developing Mns. These data support that the size principle governs the recruitment order in neonatal Mns and is maintained in adult Mns of the oculomotor nucleus; but during postnatal development the crucial property in determining recruitment order in these Mns was not the modifications of cell size-input resistance but of voltage threshold