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Abstract Motile cells can use and switch between different modes of migration. Here, we use traction force microscopy and fluorescent labeling of actin and myosin to quantify and correlate traction force patterns and cytoskeletal distributions in Dictyostelium discoideum cells that move and switch between keratocyte‐like fan‐shaped, oscillatory, and amoeboid modes. We find that the wave dynamics of the cytoskeletal components critically determine the traction force pattern, cell morphology, and migration mode. Furthermore, we find that fan‐shaped cells can exhibit two different propulsion mechanisms, each with a distinct traction force pattern. Finally, the traction force patterns can be recapitulated using a computational model, which uses the experimentally determined spatiotemporal distributions of actin and myosin forces and a viscous cytoskeletal network. Our results suggest that cell motion can be generated by friction between the flow of this network and the substrate.

Congenital anomalies (CA) encompass all morphological or functional alterations originating prenatally and present at birth. The prenatal diagnosis of these anomalies can significantly impact the overall health of the pregnant individual and may influence her decision regarding the continuation of the pregnancy. In contexts where safe pregnancy termination is not guaranteed by the state, it can lead to unsafe procedures with severe consequences. In our research, we analyzed epidemiological information on CA to develop potential indicators of inequity in access to safe abortion prior to the legalization of legal termination of pregnancy in Argentina. We included cases from 13 public hospitals and 9 non-public subsector hospitals, from the period 2013–2020. Two groups of specific CA were selected: 1) CA capable of being prenatally diagnosed, and 2) CA related to vascular disruptive events. 10/18 of the selected CA capable of being prenatally diagnosed had a significantly higher prevalence in public hospitals (anencephaly, encephalocele, spina bifida, microcephaly, hydrocephalus, holoprosencephaly, hydranencephaly, diaphragmatic hernia, gastroschisis, bilateral renal agenesis). Non public hospitals had higher prenatal detection. Birth prevalence of CA related with vascular disruptive events (limb reduction, Moebius syndrome, amniotic band sequence) were significantly higher in public hospitals. These results suggest disparities in access to prenatal diagnosis and safe abortion based on socioeconomic status. There was a significant gap in access to prenatal diagnosis for CA and possibly to safe elective abortion depending on the type of institution (public vs. non-public). [ABSTRACT FROM AUTHOR]

Transitivity, the existence of periodic points, and positive topological entropy can be used to characterize complexity in dynamical systems. It is known that, for every graph that is not a tree and any ε > 0, there exist (complicated) totally transitive maps (then with cofinite set of periods) such that the topological entropy is smaller than ε (simplicity). To numerically measure the complexity of the set of periods, we introduce a notion of the boundary of cofiniteness. Larger boundary of cofiniteness corresponds to a simpler set of periods. We show that, for any continuous circle maps of degree one, every totally transitive (and, hence, robustly complicated) map with small topological entropy has arbitrarily large (simplicity) boundary of cofiniteness. [ABSTRACT FROM AUTHOR]

Aim: To assess in a pilot study the prevalence and severity of dental caries among pregnant women compared to non-pregnant women in the state of Rio de Janeiro, Brazil. Materials and methods: A cross-sectional, observational study was conducted. Data collection consisted of clinical examinations and general questionnaires concerning oral hygiene habits and recent dental visits of pregnant and non-pregnant women. Prevalence and severity of caries was determined by the CAST index and the CAST severity score. Permission for this study was granted by the National Research Ethics Commission of Brazil. Written informed consent was obtained from all participants. Results: In total, 67 pregnant women were included (mean age (SD) 25.5 ± 5.4 years) and 79 non-pregnant women (26.0 ± 5.3 years). Mean number of teeth with untreated caries (CAST 4–7) among pregnant women was significantly lower (1.2 ± 1.8) compared to non-pregnant women (2.7 ± 4.0; Mann-Whitney test, p = 0.027). In both groups, 40–60% were in need of curative treatment. There was no significant difference between the two groups in frequency of dental visits (p > 0.05), but pregnant women brushed their teeth more often (Mann-Whitney test, p < 0.001). Conclusion: Pregnant women in the state of Rio de Janeiro have fewer untreated caries and less severe dental caries compared to non-pregnant women. Still, half of all women in this study are in need of curative treatment for at least one tooth. Effective preventive programs should therefore be developed to stimulate preventive oral care among all women. [ABSTRACT FROM AUTHOR]

Anti-neoplastic effect of DNA cross-linking agents such as cisplatin, mitomycin C, and psoralen is attributed to their ability to induce DNA interstrand cross-links (ICLs), which block replication, transcription, and linear repair pathways by preventing DNA strand separation and trigger apoptosis. It is generally agreed that the Fanconi anemia (FA) pathway orchestrates the removal of ICLs by the combined actions of various DNA repair pathways. Recently, attention has been focused on the ability of the NEIL3-initiated base excision repair pathway to resolve psoralen- and abasic site-induced ICLs in an FA-independent manner. Intriguingly, overexpression of NEIL3 is associated with chemo-resistance and poor prognosis in many solid tumors. Here, using loss- and gain-of-function approaches, we demonstrate that NEIL3 confers resistance to cisplatin and participates in the removal of cisplatin–DNA adducts. Proteomic studies reveal that the NEIL3 protein interacts with the 26S proteasome in a cisplatin-dependent manner. NEIL3 mediates proteasomal degradation of WRNIP1, a protein involved in the early step of ICL repair. We propose that NEIL3 participates in the repair of ICL-stalled replication fork by recruitment of the proteasome to ensure a timely transition from lesion recognition to repair via the degradation of early-step vanguard proteins. [ABSTRACT FROM AUTHOR]

Abstract The efficient sequestration of nutrients is vital for the growth and survival of microorganisms. Some nutrients, such as CO2 and NH3, are readily diffusible across the cell membrane. The large membrane permeability of these nutrients obviates the need of transporters when the ambient level is high. When the ambient level is low, however, maintaining a high intracellular nutrient level against passive back diffusion is both challenging and costly. Here, we study the delicate management of ammonium (NH4+/NH3) sequestration by E. coli cells using microfluidic chemostats. We find that as the ambient ammonium concentration is reduced, E. coli cells first maximize their ability to assimilate the gaseous NH3 diffusing into the cytoplasm and then abruptly activate ammonium transport. The onset of transport varies under different growth conditions, but always occurring just as needed to maintain growth. Quantitative modeling of known interactions reveals an integral feedback mechanism by which this need‐based uptake strategy is implemented. This novel strategy ensures that the expensive cost of upholding the internal ammonium concentration against back diffusion is kept at a minimum.

The celebrated Brouwer translation theorem asserts that for a preserving orientation fixed point free homeomorphism of the plane, each point belongs to an invariant region where the dynamics is continuously conjugate to a translation. In this work we prove that if we start with a C m , m ∈ N ∪ { ∞ } , diffeomorphism then the referred conjugacy has the same kind of regularity. [ABSTRACT FROM AUTHOR]

Objective: This study evaluated the preventive effect of a chitosan gel containing CaneCPI-5 against enamel erosion and erosion + abrasion in situ. Methods: Sixteen volunteers participated in a crossover, double-blind protocol, comprising 4 phases: (1) no treatment (Nt); (2) chitosan gel (Cg); (3) chitosan gel + 12,300 ppm NaF (Cg + NaF); and (4) chitosan gel + 0.1 mg/mL CaneCPI-5 (Cg + Cane). Volunteers wore an appliance containing 4 specimens. Once/day, they applied the gel (except for Nt) (4 min/specimen). Erosive challenges were performed extra-orally (0.1% citric acid, 90 s, 4 × /day; ERO). Specimens were also abraded (toothbrush, 15 s/specimen, 2 × /day; ERO + ABR). Enamel wear was assessed by profilometry and relative surface reflection intensity (%SRI). Two-way RM-ANOVA/Sidak's tests and Spearman's correlation were used (p < 0.05). Results: For profilometry, ERO + ABR promoted significantly greater wear when compared with ERO. There was a significant difference among all treatments. The lowest enamel loss occurred for Cg + Cane, followed by Cg + NaF, Cg, and Nt (p < 0.05). The %SRI was significantly lower for ERO + ABR when compared to ERO, only for the Nt group. The greatest %SRI was found for the Cg + NaF and Cg + Cane groups, which did not differ significantly, regardless of the conditions. The lowest %SRI was found for the Nt and Cg groups, which did not differ from each other, regardless of the conditions. The Nt group did not differ significantly from the Cg + NaF (ERO). There was a significant correlation between both analyses. Conclusion: The incorporation of CaneCPI-5 in the chitosan gel prevented erosive wear in situ. Clinical relevance: These results open a new perspective for the use of CaneCPI-5 in other application vehicles, such as chitosan gel. [ABSTRACT FROM AUTHOR]

To analyze the effect of a sugarcane cystatin (CaneCPI-5) on the microbial profile and viability, as well as on the prevention of dentin demineralization using a microcosm biofilm model. Ninety bovine dentine specimens were divided into five experimental groups according with the solution they were treated for 60 s: (1) PBS (negative control), (2) 0.12% chlorhexidine (positive control), (3) Fluoride (500 ppm F, as NaF), (4) 0.025 mg/ml CaneCPI-5, and (5) 0.05 mg/ml CaneCPI-5. Specimens were incubated with inoculum (McBain's saliva plus human saliva) in the first 8 h, and from then on, they were exposed to McBain saliva containing sucrose and daily treated (60 s) with the solutions for 5 days. Resazurin and colony-forming unit counting assays were performed. Dentin demineralization was measured by transverse micro-radiography (TMR). 0.12% chlorhexidine significantly reduced the metabolic activity of the microcosm biofilm in relation to the negative control and treated groups (p < 0.01). CHX and F significantly reduced the counts of total microorganisms, mutans group streptococci, and lactobacilli when compared with the negative control. None of the treatments was able to significantly reduce dentin demineralization in comparison with the negative control. In the model evaluated, CaneCPI-5 neither altered the microcosm biofilm profile and viability nor protected dentin against demineralization. [ABSTRACT FROM AUTHOR]

Birth prevalence of congenital anomalies (CA) in Argentina is estimated around 1.7%. CA are the second leading cause of infant mortality. Poverty and other adverse socioeconomic conditions have been associated with birth defects. To describe the prevalence at birth of CA, according to the two proxy variables of socioeconomic level: the health subsector of the hospital where the cases were born (PUB-public versus PRI-private or social security) and its geographical location. The design of the study was ecological using the data of the National Network of Congenital Anomalies of Argentina (RENAC); from October 2010 to December 2018. CA birth prevalence was estimated using the Poisson regression. We used a logistic regression model to analyze the association birth prevalence to health subsector and geographical region. A total of 2,202,994 births were examined in the study period, with a global CA prevalence of 1.69% (95% CI 1.68–1.71). The highest prevalence was observed in PUB hospitals when comparing to PRI hospitals at the country level and in all regions. There were differences in the prevalence of selected congenital anomalies with a statistically significant association to PUB (observed in anencephaly, encephalocele, hydrocephalus, microcephaly, holoprosencephaly, microtia/anotia, cleft lip and palate, postaxial polydactyly, talipes equinovarus, talipes calcaneovalgus, and gastroschisis). The prevalence of critical heart defects and chromosomal anomalies was significantly higher in PRI hospitals. Although this is an ecological study with no information on socioeconomic status at individual level, we found an association between CA frequency and selected CA with the PUB subsector. Vulnerable populations affected with CA require a greater effort from policy makers and health care providers to allocate more resources and design strategies to access to health. [ABSTRACT FROM AUTHOR]

Motivated by tumor growth models we establish conditions for the R-positivity of Markov processes and positive matrices. We then apply them to obtain the asymptotic behavior of the tumors sizes in the supercritical regime. [ABSTRACT FROM AUTHOR]

Congenital anomalies (CAs) are a leading cause of neonatal death. Many CAs can be diagnosed prenatally. To estimate the prenatal detection rate (PDR) of CA in hospitals participating in the RENAC (National Network of Congenital Anomalies of Argentina) and to analyze the PDR according to different factors. Sources were reports of RENAC from the 2013–2016 period. Congenital anomalies included were those detectable by ultrasound or by a prenatal karyotype. PDR was calculated by region, health subsector, clinical presentation, maternal age, sex, and twining. Using multiple logistic regression analysis, we evaluated predictors of prenatal detection. In total, 9976 cases were defined as prenatal detectable; 5021 were detected (PDR = 50.3%). Multiple presentation increased the chances of prenatal detection (Adj. OR = 1.6; 95%CI 1.4–1.9). Prenatal detection was lower in the public subsector (Adj. OR = 0.8; 95%CI 0.7–0.9) and in the northern regions of the country. PDR was higher than 75% in isolated cases of urinary malformation, anencephaly, and gastroschisis. Prenatal detection increased the chance of birth in higher complexity–level hospitals (Adj. OR = 2.5; 95%CI 2.3–2.8). PDR was within the range previously reported. Heterogeneity between regions and health subsector suggests the need for training to achieve equity in detection. [ABSTRACT FROM AUTHOR]

The goal of our study is to describe the prevalence of congenital anomalies (CA) in hospitals of the City of Buenos Aires, Argentina, according to two proxy variables of the socioeconomic level: health subsector, public (PUB) versus private/social security (PRI), and geographical location, northern (N) versus southern (S). The source of data was the National Network of Congenital Anomalies of Argentina (RENAC) (period 2010–2016). From a total of 228,208 births, 4872 newborns with CA were detected (2.14%). The prevalence in PRI-N, PUB-N, PRI-S, and PUB-S hospitals were 1.59%, 1.91%, 2.20%, and 2.43%, respectively. Prevalence of neural tube defects, abdominal wall defects, and oral clefts was significantly higher in PUB than in PRI hospitals. Prevalence of critical heart defects was significantly lower in PUB-N and in PRI-S hospitals. Prevalence of anencephaly, encephalocele, hydrocephalus, microcephaly, gastroschisis, cleft lip and palate, ductus arteriosus, and bilateral renal agenesis was higher in PUB hospitals, both N and S, as well as microphthalmia/anophthalmia and ambiguous genitalia, spina bifida, anotia/microtia, postaxial polydactyly, and diaphragmatic hernia had higher prevalences in PUB-S hospitals. Omphalocele was more frequent in PUB-N hospitals. Results suggest that vulnerable populations in the public and southern subsectors of the city still require a greater support to reinforce resources and strategies that lead to greater equity in access to health. [ABSTRACT FROM AUTHOR]

Damaged DNA bases are removed by the base excision repair (BER) mechanism. This enzymatic process begins with the action of one of DNA glycosylases, which recognize damaged DNA bases and remove them by hydrolyzing N-glycosidic bonds with the formation of apurinic/apyrimidinic (AP) sites. Apurinic/apyrimidinic endonuclease 1 (APE1) hydrolyzes the phosphodiester bond on the 5′-side of the AP site with generation of the single-strand DNA break. A decrease in the functional activity of BER enzymes is associated with the increased risk of cardiovascular, neurodegenerative, and oncological diseases. In this work, we developed a fluorescence method for measuring the activity of key human DNA glycosylases and AP endonuclease in cell extracts. The efficacy of fluorescent DNA probes was tested using purified enzymes; the most efficient probes were tested in the enzymatic activity assays in the extracts of A549, MCF7, HeLa, WT-7, HEK293T, and HKC8 cells. The activity of enzymes responsible for the repair of AP sites and removal of uracil and 5,6-dihydrouracil residues was higher in cancer cell lines as compared to the normal HKC8 human kidney cell line. [ABSTRACT FROM AUTHOR]

Birth defects (BDs) are structural or functional anomalies, sporadic or hereditary, of prenatal origin. Public health surveillance is defined as the ongoing systematic collection, analysis, and interpretation of outcome-specific data for use in the planning, implementation, and evaluation of public health practice. BD surveillance systems may have different characteristics according to design, coverage, type of surveillance, case ascertainment, case definition, BD description, maximum age of diagnosis, pregnancy outcomes, coding systems, and the location of the coding process (central or local). The aim of this article is to describe and compare methodology, applications, and results of birth defect surveillance systems in two South-American countries: Colombia and Argentina. In both countries, the surveillance systems developed activities in relation to the Zika virus emergency. For most BDs, a statistically significant higher prevalence is observed in Argentina-RENAC than in Colombian registries. This may be due to methodological reasons or real differences in prevalence. The strengths, weaknesses, and the future perspectives of the Argentine and Colombian systems are presented. When developing a surveillance system, the objectives, the available resources, and previous experiences in similar contexts must be taken into account. In that sense, the experience of Argentina and Colombia can be useful for others when developing a birth defect surveillance system. [ABSTRACT FROM AUTHOR]

Birth defects (BD), also known as congenital anomalies, are structural or functional abnormalities present at birth as a result of abnormal prenatal development. Their cause can be broadly categorized as genetic, environmental, or a combination of both. It is estimated that approximately 3-6% of newborn infants worldwide are affected by BD, many of which are associated with serious morbidity, mortality, and lifelong disabilities. The International Clearinghouse for Birth Defects Surveillance and Research (ICBDSR), founded in 1974, promotes worldwide birth defect surveillance, research, and prevention through the ongoing sharing of data, expertise, and training. In this review, we show value and contribution of BD surveillance systems in pursuing these aims. In the time of personalized medicine for many rare and common diseases, there are still massive gaps in our understanding of the causes and mechanisms of many birth defects, especially structural congenital anomalies. The main aim of the Sustainable Development Goals (SDGs), adopted by the United Nations in 2015, is to ensure healthy lives and promote well-being for all children. One specific goal is to end preventable deaths of newborns and children less than 5 years of age by 2030. The SDGs also underscore the need to consider BD as a priority in the global child health agenda. It can be said that counting BD helps BD to count. By sharing data and expertise and joining in surveillance and research, BD surveillance programs can play a major role in increasing our understanding of the causes of BD, and promoting prevention. [ABSTRACT FROM AUTHOR]

The formation of condensed matter typically involves a trade-off between structural order and flexibility. As the extent and directionality of interactions between atomic or molecular components increase, materials generally become more ordered but less compliant, and vice versa. Nevertheless, high levels of structural order and flexibility are not necessarily mutually exclusive; there are many biological (such as microtubules [1], [2], flagella [3], viruses [4], [5]) and synthetic assemblies (for example, dynamic molecular crystals [6]- [9] and frameworks [10]- [13]) that can undergo considerable structural transformations without losing their crystalline order and that have remarkable mechanical properties [8], [14], [15] that are useful in diverse applications, such as selective sorption [16], separation [17], sensing [18] and mechanoactuation [19]. However, the extent of structural changes and the elasticity of such flexible crystals are constrained by the necessity to maintain a continuous network of bonding interactions between the constituents of the lattice. Consequently, even the most dynamic porous materials tend to be brittle and isolated as microcrystalline powders [14], whereas flexible organic or inorganic molecular crystals cannot expand without fracturing. Owing to their rigidity, crystalline materials rarely display self-healing behaviour [20]. Here we report that macromolecular ferritin crystals with integrated hydrogel polymers can isotropically expand to 180 per cent of their original dimensions and more than 500 per cent of their original volume while retaining periodic order and faceted Wulff morphologies. Even after the separation of neighbouring ferritin molecules by 50 ångströms upon lattice expansion, specific molecular contacts between them can be reformed upon lattice contraction, resulting in the recovery of atomic-level periodicity and the highest-resolution ferritin structure reported so far. Dynamic bonding interactions between the hydrogel network and the ferritin molecules endow the crystals with the ability to resist fragmentation and self-heal efficiently, whereas the chemical tailorability of the ferritin molecules enables the creation of chemically and mechanically differentiated domains within single crystals. The integration of macromolecular ferritin protein crystals with hydrogel polymers gives a composite material that expands isotropically and reversibly to twice its size while maintaining periodicity, resists fragmentation and self-heals efficiently. [ABSTRACT FROM AUTHOR]

During the past several decades, the Earth system has changed significantly, especially across Northern Eurasia. Changes in the socio-economic conditions of the larger countries in the region have also resulted in a variety of regional environmental changes that can have global consequences. The Northern Eurasia Future Initiative (NEFI) has been designed as an essential continuation of the Northern Eurasia Earth Science Partnership Initiative (NEESPI), which was launched in 2004. NEESPI sought to elucidate all aspects of ongoing environmental change, to inform societies and, thus, to better prepare societies for future developments. A key principle of NEFI is that these developments must now be secured through science-based strategies co-designed with regional decision-makers to lead their societies to prosperity in the face of environmental and institutional challenges. NEESPI scientific research, data, and models have created a solid knowledge base to support the NEFI program. This paper presents the NEFI research vision consensus based on that knowledge. It provides the reader with samples of recent accomplishments in regional studies and formulates new NEFI science questions. To address these questions, nine research foci are identified and their selections are briefly justified. These foci include warming of the Arctic; changing frequency, pattern, and intensity of extreme and inclement environmental conditions; retreat of the cryosphere; changes in terrestrial water cycles; changes in the biosphere; pressures on land use; changes in infrastructure; societal actions in response to environmental change; and quantification of Northern Eurasia's role in the global Earth system. Powerful feedbacks between the Earth and human systems in Northern Eurasia (e.g., mega-fires, droughts, depletion of the cryosphere essential for water supply, retreat of sea ice) result from past and current human activities (e.g., large-scale water withdrawals, land use, and governance change) and potentially restrict or provide new opportunities for future human activities. Therefore, we propose that integrated assessment models are needed as the final stage of global change assessment. The overarching goal of this NEFI modeling effort will enable evaluation of economic decisions in response to changing environmental conditions and justification of mitigation and adaptation efforts. [ABSTRACT FROM AUTHOR]

Background: Companioned by economic development, a dietary shift toward higher meat consumption is seen in developing countries and transitional economies, where the demand for livestock production has been increasing in response to such a dietary shift. In the Asian Dryland Belt, approaches to meet this demand have focused on grazing intensification, cropland conversion for animal feed, and supplemental feeding. With the scarcity of water, energy, and food in the region, a key question is whether or not the current approaches are sustainable. If not, what are the pathways to increase livestock production while protecting the region's environment for a sustainable future? We provide our reviews and discuss current approaches in response to these dietary shifts and assess their environmental resilience with a focus on the grassland ecosystems in the Asian Dryland Belt. Results: While current approaches alleviate the urgent need for short-term livestock production, they lead to long-term vulnerability in food security. Trade-offs between short gains and long-term losses, between food for humans and for animals, and between agricultural intensification and environmental degradation need to be holistically examined for the sustainable development of the region. A grassland water, energy, and food nexus framework is proposed with specific recommendations to increase livestock production while considering other ecosystem services of the dryland grassland ecosystems in the Asian Dryland Belt. Conclusions: Current practices to increase livestock production are likely to lead to long-term, large-scale ecological degradation of the grassland ecosystems in the Asian Dryland Belt and are thus unsustainable. By considering the trade-offs in the nexus of water, land, food, and livelihoods, sustainable pathways were articulated and recommended. Future pilot studies are needed for validation and adoption. [ABSTRACT FROM AUTHOR]

Geographical clusters are defined as the occurrence of an unusual number of cases higher than expected in a given geographical area in a certain period of time. The aim of this study was to identify potential geographical clusters of specific selected congenital anomalies (CA) in Argentina. The cases were ascertained from 703,325 births, examined in 133 maternity hospitals in the 24 provinces of Argentina. We used the spatial scan statistic to determine areas of Argentina which had statistically significant elevations of prevalence. Prenatal diagnosis followed by referral of high-risk pregnancies to high complexity hospitals in a hospital-based surveillance system can create artifactual clusters. We assessed the referral bias by evaluating the prevalence heterogeneity within each cluster. Eight clusters of selected CAs with unusually high birth prevalence were identified: anencephaly, encephalocele, spina bifida, diaphragmatic hernia, talipes equinovarus, omphalocele, Cleft lip with or without cleft palate (CL/P), and Down syndrome. The clusters of Down syndrome and CL/P observed in this study match the previously reported clusters. These findings support local targeted interventions to lower the prevalence of the CAs and/or further research on the cause of each cluster. The clusters of spina bifida, anencephaly, encephalocele, omphalocele, congenital diaphragmatic hernia, and talipes equinovarus may be influenced by prenatal diagnosis and referral to high complexity hospitals. [ABSTRACT FROM AUTHOR]

TWIST1 is a highly conserved basic helix-loop-helix transcription factor that promotes epithelial-mesenchymal transition (EMT). Its misregulation has been observed in various types of tumors. Using the MCF-10A-series of cell lines that recapitulate the early stages of breast cancer formation and EMT, we found TWIST1 to be upregulated during EMT and downregulated early in carcinogenesis. The TWIST1 3′UTR contains putative regulatory elements, including miRNA target sites and two cytoplasmic polyadenylation elements (CPE). We found that miR-580, CPEB1, and CPEB2 act as negative regulators of TWIST1 expression in a sequence-specific and additive/cooperative manner. [ABSTRACT FROM AUTHOR]

We present a reconstruction algorithm that resolves cellular tractions in diffraction-limited nascent adhesions (NAs). The enabling method is the introduction of sparsity regularization to the solution of the inverse problem, which suppresses noise without underestimating traction magnitude. We show that NAs transmit a distinguishable amount of traction and that NA maturation depends on traction growth rate. A software package implementing this numerical approach is provided. [ABSTRACT FROM AUTHOR]

Birth defects are a global problem, but their impact is particularly severe in low and middle income countries, where the conditions for prevention, treatment, and rehabilitation are more critical. The epidemiological transition in the infant mortality causes, and the concern of the community and the mass media about the teratogenic risk of environmental pollutants, has made health authorities aware of the importance of birth defects in Argentina. The objective of this paper is to outline those actions specifically taken in Argentina aimed at the prevention of birth defects at a national level. Firstly, we focus on birth defects in Argentina on a general basis, and then we present different laws and actions taken in terms of surveillance and public health programs, primary, secondary, and tertiary prevention. Finally, we present the Teratology Information Service 'Fetal Health Line', and the genetic services organization and health professionals training by the National Center of Medical Genetics and the National Program of Genetics Network. In conclusion, in the country, several programs focus on different approaches to the problem, and the challenge is to coordinate the teamwork between them. Finally, we list tips to address birth defects from the public health perspective. [ABSTRACT FROM AUTHOR]

We consider Gibbs distributions on the set of permutations of $${\mathbb Z}^d$$ associated to the Hamiltonian $$H(\sigma ):=\sum _{x} {V}(\sigma (x)-x)$$ , where $$\sigma $$ is a permutation and $${V}:{\mathbb Z}^d\rightarrow {\mathbb R}$$ is a strictly convex potential. Call finite-cycle those permutations composed by finite cycles only. We give conditions on $${V}$$ ensuring that for large enough temperature $$\alpha >0$$ there exists a unique infinite volume ergodic Gibbs measure $$\mu ^\alpha $$ concentrating mass on finite-cycle permutations; this measure is equal to the thermodynamic limit of the specifications with identity boundary conditions. We construct $$\mu ^{\alpha }$$ as the unique invariant measure of a Markov process on the set of finite-cycle permutations that can be seen as a loss-network, a continuous-time birth and death process of cycles interacting by exclusion, an approach proposed by Fernández, Ferrari and Garcia. Define $$\tau _v$$ as the shift permutation $$\tau _v(x)=x+v$$ . In the Gaussian case $${V}=\Vert \cdot \Vert ^2$$ , we show that for each $$v\in {\mathbb Z}^d$$ , $$\mu ^\alpha _v$$ given by $$\mu ^\alpha _v(f)=\mu ^\alpha [f(\tau _v\cdot )]$$ is an ergodic Gibbs measure equal to the thermodynamic limit of the specifications with $$\tau _v$$ boundary conditions. For a general potential $${V}$$ , we prove the existence of Gibbs measures $$\mu ^\alpha _v$$ when $$\alpha $$ is bigger than some $$v$$ -dependent value. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this research was to evaluate the effect of ultrasound on mass transport across fetal membrane for direct fetal drug delivery and sensing of the amniotic fluid in a noninvasive manner. Methods: Post-delivery human fetal membranes (chorioamnion) were used for in vitro experiments, in which the effect of ultrasound on transport across fetal membrane of fluorescent model molecule (250 kDa) was evaluated. Ex vivo experiments were carried out on a whole rat amniotic sac. The model molecule or alpha-fetoprotein was injected into the amniotic sac through the placenta. Transport of these molecules across pre- and post-insonation of the amniotic sac was evaluated. The ultrasound enhancement's mechanism was also assessed. Results: The greatest enhancement in mass transport (43-fold) in vitro was achieved for 5 min of insonation (20 kHz, 4.6 W/cm, 5 mm distance). Ex vivo results showed a rapid increase (23-fold) in mass transport of the model molecule and also for alphafetoprotein following 30 s of insonation (20 kHz, 4.6 W/cm, 5 mm distance). Conclusions: Mass transport across fetal membranes was enhanced post-insonation both in vitro and ex vivo in a reversible and transient manner. We suggest that exterior (to the amniotic sac) ultrasound-induced cavitation is the main mechanism of action. [ABSTRACT FROM AUTHOR]

Cell signaling, one of key processes in both normal cellular function and disease, is coordinated by numerous interactions between membrane proteins that change in response to stimuli. We present a split ubiquitin-based method for detection of integral membrane protein-protein interactions (PPIs) in human cells, termed mammalian-membrane two-hybrid assay (MaMTH). We show that this technology detects stimulus (hormone or agonist)-dependent and phosphorylation-dependent PPIs. MaMTH can detect changes in PPIs conferred by mutations such as those in oncogenic ErbB receptor variants or by treatment with drugs such as the tyrosine kinase inhibitor erlotinib. Using MaMTH as a screening assay, we identified CRKII as an interactor of oncogenic EGFR(L858R) and showed that CRKII promotes persistent activation of aberrant signaling in non-small cell lung cancer cells. MaMTH is a powerful tool for investigating the dynamic interactomes of human integral membrane proteins. [ABSTRACT FROM AUTHOR]

Background: Eukaryotic translation elongation factor 1A2 (eEF1A2) is a known proto-oncogene. We proposed that stimulation of the eEF1A2 expression in cancer tissues is caused by the loss of miRNA-mediated control.Methods: Impact of miRNAs on eEF1A2 at the mRNA and protein levels was examined by qPCR and western blot, respectively. Dual-luciferase assay was applied to examine the influence of miRNAs on 3'-UTR of EEF1A2. To detect miRNA-binding sites, mutations into the 3'-UTR of EEF1A2 mRNA were introduced by the overlap extension PCR.Results: miR-663 and miR-744 inhibited the expression of luciferase gene attached to the 3'-UTR of EEF1A2 up to 20% and 50%, respectively. In MCF7 cells, overexpression of miR-663 and miR-744 reduced the EEF1A2 mRNA level by 30% and 50%. Analogous effects were also observed at the eEF1A2 protein level. In resveratrol-treated MCF7 cells the upregulation of mir-663 and mir-744 was accompanied by downregulation of EEF1A2 mRNA. Both miRNAs were able to inhibit the proliferation of MCF7 cells.Conclusion: miR-663 and miR-744 mediate inhibition of the proto-oncogene eEF1A2 expression that results in retardation of the MCF7 cancer cells proliferation. Antitumour effect of resveratrol may include stimulation of the miR-663 and miR-744 expression. [ABSTRACT FROM AUTHOR]

Health needs assessment (HNA) is a commonly used process for those working in public health. The PHG Foundation has developed a Toolkit to provide users with a stepwise approach for undertaking a HNA on birth defects. We report the findings from using the Toolkit to examine needs in relation to policies and programs, services, and interventions for neural tube defects (NTDs) in Argentina. The trend over the last few decades is one of decline in infant mortality from nutritional and infectious causes, thus further increasing the relative importance of birth defects. The observed prevalence of NTDs is consistent with that reported internationally. Since 2002 folic acid fortification (FAF) has been mandatory by law, and different studies have shown at least a 50 % decrease in the birth prevalence of NTDs after FAF. In Argentina, there is inequity between the public and non-public health sectors. The birth prevalence of NTDs seems lower in the non-public sector, possibly as a result of better nutritional status of women, higher access to folic acid supplementation, and earlier prenatal diagnosis followed by termination of pregnancy (ToP) in non-public hospitals. Although illegal, ToP is believed to be widespread, with better access for people of higher socioeconomic status. Through the process of HNA, we identified several unmet needs regarding registration of cases, public and professional education, legislation, and organization of care pathways. In our experience, the Toolkit brought together people working on the same issue, and it engaged and motivated experts and stakeholders to work together to tackle the problem. [ABSTRACT FROM AUTHOR]

Consider a system of independent random walks in the discrete torus with creation-annihilation of particles and possible explosion of the total number of particles in finite time. Rescaling space and rates for diffusion/creation/annihilation of particles, we obtain a strong law of large numbers for the density of particles in the supremum norm. The limiting object is a classical solution to the semilinear heat equation ∂ u= ∂ u+ f( u). If f( u)= u, 1< p≤3, we also obtain a law of large numbers for the explosion time. [ABSTRACT FROM AUTHOR]

Most leukocytes can roll along the walls of venules at low shear stress (1?dyn?cm?2), but neutrophils have the ability to roll at tenfold higher shear stress in microvessels in vivo. The mechanisms involved in this shear-resistant rolling are known to involve cell flattening and pulling of long membrane tethers at the rear. Here we show that these long tethers do not retract as postulated, but instead persist and appear as 'slings' at the front of rolling cells. We demonstrate slings in a model of acute inflammation in vivo and on P-selectin in vitro, where P-selectin-glycoprotein-ligand-1 (PSGL-1) is found in discrete sticky patches whereas LFA-1 is expressed over the entire length on slings. As neutrophils roll forward, slings wrap around the rolling cells and undergo a step-wise peeling from the P-selectin substrate enabled by the failure of PSGL-1 patches under hydrodynamic forces. The 'step-wise peeling of slings' is distinct from the 'pulling of tethers' reported previously. Each sling effectively lays out a cell-autonomous adhesive substrate in front of neutrophils rolling at high shear stress during inflammation. [ABSTRACT FROM AUTHOR]

The facultative intracellular pathogen Salmonella enterica resides within a membrane-bound compartment inside macrophages. This compartment must be acidified for Salmonella to survive within macrophages, possibly because acidic pH promotes expression of Salmonella virulence proteins. We reasoned that Salmonella might sense its surroundings have turned acidic not only upon protonation of the extracytoplasmic domain of a protein sensor but also by an increase in cytosolic ATP levels, because conditions that enhance the proton gradient across the bacterial inner membrane stimulate ATP synthesis. Here we report that an increase in cytosolic ATP promotes transcription of the coding region for the virulence gene mgtC, which is the most highly induced horizontally acquired gene when Salmonella is inside macrophages. This transcript is induced both upon media acidification and by physiological conditions that increase ATP levels independently of acidification. ATP is sensed by the coupling/uncoupling of transcription of the unusually long mgtC leader messenger RNA and translation of a short open reading frame located in this region. A mutation in the mgtC leader messenger RNA that eliminates the response to ATP hinders mgtC expression inside macrophages and attenuates Salmonella virulence in mice. Our results define a singular example of an ATP-sensing leader messenger RNA. Moreover, they indicate that pathogens can interpret extracellular cues by the impact they have on cellular metabolites. [ABSTRACT FROM AUTHOR]

Central Asia is one of the most vulnerable regions on the planet earth to global climate change, depending on very fragile natural resources. The Soviet legacy has left the five countries (Kazakhstan, Tajikistan, Kyrgyzstan, Turkmenistan, and Uzbekistan) with a highly integrated system but they are facing great challenges with tensions that hinder regional coordination of food and water resources. With increasing climate variability and warming trend in the region, food and water security issues become even more crucial now and, if not addressed properly, could affect the regional stability. The long-term drivers of these two most critical elements, food and water, are climate change; the immediate and probably more drastic factors affecting the food and water security are land uses driven by institutional change and economic incentives. As a feedback, changes in land use and land cover have directly implications on water uses, food production, and lifestyles of the rural community in the region. Regional and international efforts have been made to holistically understand the cause, extent, rate and societal implications of land use changes in the region. Much of these have been understood, or under investigation by various projects, but solutions or research effort to develop solutions, to these urgent regional issues are lacking. This article, serves as an introduction to the special issue, provides a brief overview of the challenges facing the Central Asian countries and various international efforts in place that resulted in the publications of this special issue. [ABSTRACT FROM AUTHOR]

During the past decade, the Arctic has experienced its highest temperatures of the instrumental record, even exceeding the warmth of the 1930s and 1940s. Recent paleo-reconstructions also show that recent Arctic summer temperatures are higher than at any time in the past 2000 years. The geographical distribution of the recent warming points strongly to an influence of sea ice reduction. The spatial pattern of the near-surface warming also shows the signature of the Pacific Decadal Oscillation in the Pacific sector as well as the influence of a dipole-like circulation pattern in the Atlantic sector. Areally averaged Arctic precipitation over the land areas north of 55°N shows large year-to-year variability, superimposed on an increase of about 5% since 1950. The years since 2000 have been wetter than average according to both precipitation and river discharge data. There are indications of increased cloudiness over the Arctic, especially low clouds during the warm season, consistent with a longer summer and a reduction of summer sea ice. Storm events and extreme high temperature show signs of increases. The Arctic Ocean has experienced enhanced oceanic heat inflows from both the North Atlantic and the North Pacific. The Pacific inflows evidently played a role in the retreat of sea ice in the Pacific sector of the Arctic Ocean, while the Atlantic water heat influx has been characterized by increasingly warm pulses. Recent shipboard observations show increased ocean heat storage in newly sea-ice-free ocean areas, with increased influence on autumn atmospheric temperature and wind fields. [ABSTRACT FROM AUTHOR]

Analysis of in situ and satellite data shows evidence of different regional snow cover responses to the widespread warming and increasing winter precipitation that has characterized the Arctic climate for the past 40-50 years. The largest and most rapid decreases in snow water equivalent (SWE) and snow cover duration (SCD) are observed over maritime regions of the Arctic with the highest precipitation amounts. There is also evidence of marked differences in the response of snow cover between the North American and Eurasian sectors of the Arctic, with the North American sector exhibiting decreases in snow cover and snow depth over the entire period of available in situ observations from around 1950, while widespread decreases in snow cover are not apparent over Eurasia until after around 1980. However, snow depths are increasing in many regions of Eurasia. Warming and more frequent winter thaws are contributing to changes in snow pack structure with important implications for land use and provision of ecosystem services. Projected changes in snow cover from Global Climate Models for the 2050 period indicate increases in maximum SWE of up to 15% over much of the Arctic, with the largest increases (15-30%) over the Siberian sector. In contrast, SCD is projected to decrease by about 10-20% over much of the Arctic, with the smallest decreases over Siberia (<10%) and the largest decreases over Alaska and northern Scandinavia (30-40%) by 2050. These projected changes will have far-reaching consequences for the climate system, human activities, hydrology, and ecology. [ABSTRACT FROM AUTHOR]

Snow cover plays a major role in the climate, hydrological and ecological systems of the Arctic and other regions through its influence on the surface energy balance (e.g. reflectivity), water balance (e.g. water storage and release), thermal regimes (e.g. insulation), vegetation and trace gas fluxes. Feedbacks to the climate system have global consequences. The livelihoods and well-being of Arctic residents and many services for the wider population depend on snow conditions so changes have important consequences. Already, changing snow conditions, particularly reduced summer soil moisture, winter thaw events and rain-on-snow conditions have negatively affected commercial forestry, reindeer herding, some wild animal populations and vegetation. Reductions in snow cover are also adversely impacting indigenous peoples' access to traditional foods with negative impacts on human health and well-being. However, there are likely to be some benefits from a changing Arctic snow regime such as more even run-off from melting snow that favours hydropower operations. [ABSTRACT FROM AUTHOR]

The cyclical protrusion and retraction of the leading edge is a hallmark of many migrating cells involved in processes such as development, inflammation and tumorigenesis. The molecular identity of the signalling mechanisms that control these cycles has remained unknown. Here, we used live-cell imaging of biosensors to monitor spontaneous morphodynamic and signalling activities, and employed correlative image analysis to examine the role of cyclic-AMP-activated protein kinase A (PKA) in protrusion regulation. PKA activity at the leading edge is closely synchronized with rapid protrusion and with the activity of RhoA. Ensuing PKA phosphorylation of RhoA and the resulting increased interaction between RhoA and RhoGDI (Rho GDP-dissociation inhibitor) establish a negative feedback mechanism that controls the cycling of RhoA activity at the leading edge. Thus, cooperation between PKA, RhoA and RhoGDI forms a pacemaker that governs the morphodynamic behaviour of migrating cells. [ABSTRACT FROM AUTHOR]

We introduce quantitative dynamic footprinting microscopy to resolve neutrophil rolling on P-selectin. We observed that the footprint of a rolling neutrophil was fourfold larger than previously thought, and that P-selectin-PSGL-1 bonds were relaxed at the leading edge of the rolling cell, compressed under the cell center, and stretched at the trailing edge. Each rolling neutrophil formed three to four long tethers that extended up to 16 ?m behind the rolling cell. [ABSTRACT FROM AUTHOR]

Natural habitats of some microorganisms may fluctuate erratically, whereas others, which are more predictable, offer the opportunity to prepare in advance for the next environmental change. In analogy to classical Pavlovian conditioning, microorganisms may have evolved to anticipate environmental stimuli by adapting to their temporal order of appearance. Here we present evidence for environmental change anticipation in two model microorganisms, Escherichia coli and Saccharomyces cerevisiae. We show that anticipation is an adaptive trait, because pre-exposure to the stimulus that typically appears early in the ecology improves the organism’s fitness when encountered with a second stimulus. Additionally, we observe loss of the conditioned response in E. coli strains that were repeatedly exposed in a laboratory evolution experiment only to the first stimulus. Focusing on the molecular level reveals that the natural temporal order of stimuli is embedded in the wiring of the regulatory network—early stimuli pre-induce genes that would be needed for later ones, yet later stimuli only induce genes needed to cope with them. Our work indicates that environmental anticipation is an adaptive trait that was repeatedly selected for during evolution and thus may be ubiquitous in biology. [ABSTRACT FROM AUTHOR]

Abstract??The best Sobolev trace constant is given by the first eigenvalue of a Steklov-like problem. We deal with minimizers of the Rayleigh quotient ?u?2H1(?)2/?u?2L2(??)for functions that vanish in a subsetA? ?, which we call the hole. We look for holes that minimize the best Sobolev trace constant among subsets of ? with prescribed volume. First, we find a formula for the first variation of the first eigenvalue with respect to the hole. As a consequence of this formula, we prove that when ? is a ball the symmetric hole (a centered ball) is critical when we consider deformations that preserves volume but is not optimal. Finally, we prove that by the Finite Element Method we can approximate the optimal configuration and, by means of the shape derivative, we design an algorithm to compute the discrete optimal holes. [ABSTRACT FROM AUTHOR]

The mating pathway in Saccharomyces cerevisiae has been the focus of considerable research effort, yet many quantitative aspects of its regulation still remain unknown. Using an integrated approach involving experiments in microfluidic chips and computational modelling, we studied gene expression and phenotypic changes associated with the mating response under well-defined pheromone gradients. Here we report a combination of switch-like and graded pathway responses leading to stochastic phenotype determination in a specific range of pheromone concentrations. Furthermore, we show that these responses are critically dependent on mitogen-activated protein kinase (MAPK)-mediated regulation of the activity of the pheromone-response-specific transcription factor, Ste12, as well as on the autoregulatory feedback of Ste12. In particular, both the switch-like characteristics and sensitivity of gene expression in shmooing cells to pheromone concentration were significantly diminished in cells lacking Kss1, one of the MAP kinases activated in the mating pathway. In addition, the dynamic range of gradient sensing of Kss1-deficient cells was reduced compared with wild type. We thus provide unsuspected functional significance for this kinase in regulation of the mating response. [ABSTRACT FROM AUTHOR]