bluuebunny/crossref_metadata_2025_split huggingface dataset:
Folding and dimerization kinetics of bone morphogenetic protein‐2, a member of the transforming growth factor‐β family
Authors: Vallejo Luis F. , Rinas Ursula 
Published: November 2012

The kinetics of folding and dimerization of bone morphogenetic protein‐2 (BMP‐2), a disulfide‐connected, homodimeric cystine‐knot protein and a member of the transforming growth factor‐β superfamily, was analyzed under a variety of different conditions. Refolding and dimerization of BMP‐2 were extremely slow under all conditions studied, and could be described by consecutive first‐order reactions involving at least one long‐lived intermediate. The rate constants vary from ∼ 0.2 × 10−5 to ∼ 3.5 × 10−5 s−1, and were strongly dependent on temperature, redox conditions, and the presence of stabilizing or destabilizing ions. In particular, the combined impact of ionic strength and redox conditions on the rates indicates that electrostatic interactions control thiol–disulfide exchange reactions on the path from the unfolded and reduced monomers to the disulfide‐connected growth factor in a rate‐determining way.Structured digital abstract

BMP‐2 and BMP‐2bind by cross-linking study (View interaction)
Structural characterization of the second intra‐discal loop of the photoreceptor tetraspanin RDS
Authors: Chakraborty Dibyendu , Rodgers Karla K. , Conley Shannon M. , Naash Muna I. 
Published: November 2012

Vertebrate photoreceptors contain a unique tetraspanin protein known as ‘retinal degeneration slow’ (RDS). Mutations in the RDS gene have been identified in a variety of human retinal degenerative diseases, and more than 70% of these mutations are located in the second intra‐discal (D2) loop, highlighting the importance of this region. Here we examined the conformational and thermal stability properties of the D2 loop of RDS, as well as interactions with ROM–1, a non‐glycosylated homolog of RDS. The RDS D2 loop was expressed in Escherichia coli as a fusion protein with maltose binding protein (MBP). The fusion protein, referred to as MBP–D2, was purified to homogeneity. Circular dichroism spectroscopy showed that the wild‐type (WT) D2 loop consists of approximately 21% α–helix, approximately 20% β–sheet and approximately 59% random coil. D2 loop fusion proteins carrying disease‐causing mutations in RDS (e.g. R172W, C214S, N244H/K) were also examined, and conformational changes were observed (compared to wild‐type D2). In particular, the C150S, C214S and N244H proteins showed significant reductions in α–helicity. However, the thermal stability of the mutants was unchanged compared to wild‐type, and all the mutants were capable of interacting with ROM–1, indicating that this functional aspect of the isolated D2 loop remained intact in the mutants despite the observed conformational changes. An I–TASSER model of the RDS D2 loop predicted a structure consistent with the circular dichroism experiments and the structure of the conserved region of the D2 loop of other tetraspanin family members. These results provide significant insight into the mechanism of RDS complex formation and the disease process underlying RDS‐associated retinal degeneration.
Sea ice phenology and timing of primary production pulses in the Arctic Ocean
Authors: Ji Rubao , Jin Meibing , Varpe Øystein 
Published: November 2012

AbstractArctic organisms are adapted to the strong seasonality of environmental forcing. A small timing mismatch between biological processes and the environment could potentially have significant consequences for the entire food web. Climate warming causes shrinking ice coverage and earlier ice retreat in the Arctic, which is likely to change the timing of primary production. In this study, we test predictions on the interactions among sea ice phenology and production timing of ice algae and pelagic phytoplankton. We do so using the following (1) a synthesis of available satellite observation data; and (2) the application of a coupled ice‐ocean ecosystem model. The data and model results suggest that, over a large portion of the Arctic marginal seas, the timing variability in ice retreat at a specific location has a strong impact on the timing variability in pelagic phytoplankton peaks, but weak or no impact on the timing of ice‐algae peaks in those regions. The model predicts latitudinal and regional differences in the timing of ice algae biomass peak (varying from April to May) and the time lags between ice algae and pelagic phytoplankton peaks (varying from 45 to 90 days). The correlation between the time lag and ice retreat is significant in areas where ice retreat has no significant impact on ice‐algae peak timing, suggesting that changes in pelagic phytoplankton peak timing control the variability in time lags. Phenological variability in primary production is likely to have consequences for higher trophic levels, particularly for the zooplankton grazers, whose main food source is composed of the dually pulsed algae production of the Arctic.
Above‐ and belowground linkages in Sphagnum peatland: climate warming affects plant‐microbial interactions
Authors: Jassey Vincent EJ , Chiapusio Geneviève , Binet Philippe , Buttler Alexandre , Laggoun‐Défarge Fatima , Delarue Frédéric , Bernard Nadine , Mitchell Edward AD , Toussaint Marie‐Laure , Francez André‐Jean , Gilbert Daniel 
Published: November 2012

AbstractPeatlands contain approximately one third of all soil organic carbon (SOC). Warming can alter above‐ and belowground linkages that regulate soil organic carbon dynamics and C‐balance in peatlands. Here we examine the multiyear impact of in situ experimental warming on the microbial food web, vegetation, and their feedbacks with soil chemistry. We provide evidence of both positive and negative impacts of warming on specific microbial functional groups, leading to destabilization of the microbial food web. We observed a strong reduction (70%) in the biomass of top‐predators (testate amoebae) in warmed plots. Such a loss caused a shortening of microbial food chains, which in turn stimulated microbial activity, leading to slight increases in levels of nutrients and labile C in water. We further show that warming altered the regulatory role of Sphagnum‐polyphenols on microbial community structure with a potential inhibition of top predators. In addition, warming caused a decrease in Sphagnum cover and an increase in vascular plant cover. Using structural equation modelling, we show that changes in the microbial food web affected the relationships between plants, soil water chemistry, and microbial communities. These results suggest that warming will destabilize C and nutrient recycling of peatlands via changes in above‐ and belowground linkages, and therefore, the microbial food web associated with mosses will feedback positively to global warming by destabilizing the carbon cycle. This study confirms that microbial food webs thus constitute a key element in the functioning of peatland ecosystems. Their study can help understand how mosses, as ecosystem engineers, tightly regulate biogeochemical cycling and climate feedback in peatlands
The oral health of HIV‐infected Brazilian children
Authors: de Aguiar Ribeiro Apoena , Portela Maristela Barbosa , de Souza Ivete Pomarico Ribeiro 
Published: November 2012

BackgroundThe number of HIV‐infected people has increased almost continuously. Paediatric dentists should be concerned about the oral findings in HIV‐infected children and their aetiologic factors, to promote adequate treatment.AimTo present the oral health aspects of Brazilian HIV‐infected children and to verify the aetiological factors.DesignA cross‐sectional study was conducted with HIV‐infected children. During the medical appointments, children were submitted to visual‐tactile exams of oral soft tissues and teeth. All parents answered questions in a structured interview. Data were analysed using the SPSS, release 10.0 (Chicago, IL, USA).ResultsOf the 57 children examined, 39 (69.6%) presented one or more oral soft tissue manifestations. More than a half suffered from gingivitis and only 12.5% had no visible dental biofilm. A high prevalence of dental surfaces with active carious lesions was observed; mean DMFS‐m and dmfs‐m scores were 5.41 ± 5.61 and 16.77 ± 19.52, respectively. Caries activity and gingivitis were correlated with the presence of mature dental biofilm.ConclusionsPrevalence of soft tissue lesions, dental caries and gingivitis in HIV‐infected children was high and correlated to lack of satisfactory oral hygiene habits, suggesting the need of therapeutic programmes that allow these children to recover their oral health.
Characterization of serine proteases of Lumbriculus variegatus and their role in regeneration
Authors: Tweeten Kay A. , Reiner Anne 
Published: November 2012

AbstractSerine proteases, ubiquitous enzymes known to function in digestion and immune protection in both vertebrates and invertebrates and implicated in regeneration in some species, were investigated in the California blackworm, Lumbriculus variegatus. Several serine proteases, rather than a single enzyme with broad specificity, were present in tissue extracts from the worms. Extracts were treated with a fluorescein‐labeled peptide chloromethyl ketone that specifically binds to trypsin/thrombin‐like proteases. Denaturing gel electrophoresis of labeled extracts showed several serine proteases with their molecular weight ranging 28,000–38,000 daltons. The trypsin/thrombin‐like activity was localized, using the fluorescein‐conjugated reagent, to the pharynx and digestive tract of L. variegatus. Movement of cells labeled by the reagent into regenerating tissues suggests that some differentiated endodermal tissues were used for reformation of digestive structures during regeneration in L. variegatus. The types of serine proteases in the extracts were further characterized by inhibitor studies. Presence of plasmin‐like activity was indicated by degradation of fibrin by tissue homogenates from the worms and the inhibitory effect of aprotinin on enzymes in these extracts. The ability of L. variegatus extracts to generate clots when incubated with rabbit plasma and partial inhibition of extract activity by phenylmethylsulfonyl fluoride and hirudin indicated presence of thrombin‐like activity. Consistent with the detection of trypsin, chymotrypsin, and plasmin‐like enzymes in the extracts was partial inhibition of L. variegatus serine protease activity by aminoethyl benzenesulfonyl fluoride and soybean trypsin inhibitor. Selective inhibition of chymotrypsin‐like activity by N‐tosyl‐l‐phenylalanine chloromethyl ketone and chymostatin as well as trypsin‐like activity by N‐tosyl‐l‐lysine chloromethyl ketone was observed. A potential role during regeneration for serine proteases is suggested by blockage of formation of head and tail structures by aminoethyl benzenesulfonyl fluoride, an inhibitor of these proteases.
Phylogenetic and mixed Yule‐coalescent analyses reveal cryptic lineages within two South American marine snails of the genus Crepipatella (Gastropoda: Calyptraeidae)
Authors: Nuñez José J. , Vejar‐Pardo Andrés , Guzmán Benjamín E. , Barriga Elías H. , Gallardo Carlos S. 
Published: November 2012

AbstractThe presence of sibling species within the marine gastropod genus Crepipatella has complicated the taxonomy of members of the group. Since the establishment of the genus, 15 species have been described, but recent studies have indicated that there are only five valid species, two of which inhabit the coasts of Chile, namely C. dilatata and C. fecunda. The two species are morphologically indistinguishable as adults, but can be differentiated on the basis of their encapsulated developmental stages. The primary aim of this study was to reconstruct phylogeny within the genus, and to establish species limits of C. dilatata and C. fecunda, using mitochondrial DNA data. To this end, we used maximum parsimony, maximum likelihood, and Bayesian inference to reconstruct phylogenies using 589 bp of the cytochrome oxidase I (COI) gene. The mtDNA phylogenies were then used as input in a general mixed Yule‐coalescent (GMYC) analysis to estimate species boundaries. In addition, quarter likelihood mapping was used to test a posteriori the confidence of inner branch patterns in the phylogenetic tree. Both DNA tree‐based and GMYC methods provide support for five isolated lineages within this species complex. Our data also suggest that Late Pleistocene and Holocene fragmentation and subsequent range expansion events may have shaped contemporary genetic patterns of Crepipatella in South America.
Developing the evidence base for addressing inequalities and smoking in the United Kingdom
Authors: McNeill Ann , Amos Amanda , McEwen Andy , Ferguson Janet , Croghan Emma 
Published: November 2012

AbstractAimsSmoking is an increasing cause of health inequalities in high‐income countries. This supplement describes pilot projects set up in England to develop and test pathways to ensure that disadvantaged groups, where smoking is frequently the norm, are reached, encouraged and supported to stop their tobacco use. Target groups were: smokers attending centres set up for highly deprived parents; smokers with serious and enduring mental illness; pregnant smokers; prisoners/other offenders who smoked; South Asian tobacco chewers; and recent quitters from ‘routine and manual’ occupational groups.MethodsCommonalities observed across the six projects are summarized, alongside recommendations for implementation.ResultsA significant barrier to implementation was the lack of mandatory identification of tobacco users across primary, secondary and community health‐care settings and routine use of expired air carbon monoxide monitoring, particularly for high‐risk groups. Appropriate use of financial incentives and national guidance is probably necessary to achieve both this and the adoption of ‘joined‐up’ tobacco dependence treatment pathways for these target groups. Further research is needed on the impact of ‘opt out’ pathways: while resulting in increased referral rates, success rates were lower. In general, smoking cessation service targets were a barrier to implementation. Flexibility and tailoring of interventions were required and most projects trained those already working in relevant settings, given their greater understanding of target groups. Mandatory training of all frontline health‐care staff was deemed desirable.ConclusionsImplementing the findings of these projects will require resources, for training, incentivizing health‐care workers and further research. However, continuing with the status quo may result in sustained tobacco use health inequalities for the foreseeable future.
Barriers and facilitators to a criminal justice tobacco control coordinator: an innovative approach to supporting smoking cessation among offenders
Authors: Eadie Douglas , MacAskill Susan , McKell Jennifer , Baybutt Michelle 
Published: November 2012

AbstractAimsTo examine the barriers and facilitators to effective operation of a regional tobacco control coordinator working within and across criminal justice and public health, whose goal was to raise tobacco control awareness and support the development of smoking cessation treatment for offenders.DesignA reflexive, mixed‐methods case study approach using in‐depth interviews, project reports and observation of advisory board meetings.SettingThe coordinator worked with prisons, probation and police custody, where there are high levels of social disadvantage and smoking.ParticipantsInterviews (n = 34) at different stages of project with the coordinator, project advisers and local stakeholders from criminal justice and public health.MeasurementsAnalysis of facilitators and barriers and the coordinator role from different perspectives.FindingsReadiness to develop cessation services was a critical predictor of different criminal justice settings' engagement with the coordinator role. The coordinator enhanced cessation service delivery in individual prisons where there was a requirement and infrastructure in place to provide such services. In police custody, where there was no central guidance or pre‐existing requirements, efforts to establish smoking cessation on the local agenda proved ineffective. In probation settings, the coordinator documented examples of good practice and supported brief intervention training. Variability in willingness to engage limited the project's ability to create joined‐up working across criminal justice settings.ConclusionsIn the English criminal justice system, the prison service appears to provide a favourable context for development of smoking cessation support and a means of accessing hard‐to‐reach groups. Other criminal justice settings, most specifically police custody, appear less responsive to such activity. A coordinator role can improve smoking cessation support in the prison setting, and develop local improvements in tobacco control interventions in other settings such as probation, but as configured here, does not have the capacity to effect change across the criminal justice system.
Using text messaging to prevent relapse to smoking: intervention development, practicability and client reactions
Authors: Snuggs Sarah , McRobbie Hayden , Myers Katherine , Schmocker Frances , Goddard Jill , Hajek Peter 
Published: November 2012

AbstractAimsThe NHS Stop Smoking Service (NHS‐SSS) helps approximately half its clients to quit for 4 weeks. However, most initially successful quitters relapse within 6 months. Short message service (SMS) texting has been shown to facilitate stopping smoking. We describe the development, implementation and subsequent evaluation, in terms of practicability and client response, of an SMS text‐based relapse prevention intervention (RPI) delivered within routine community and specialist National Health Service (NHS) Stop Smoking Service (SSS) provision in four Primary Care Trusts.DesignText messages aimed at motivation to remain abstinent, preventing careless lapses and continuing the full course of medicine for smoking cessation were developed and sent weekly to clients' mobile phones for 12 weeks and fortnightly for 6 months. They were asked to respond to some of the texts and contact the NHS SSS if they lapsed. They were also offered free nicotine mini lozenges to be sent via the mail on three occasions.SettingNHS SSS.Participants202 clients who had been abstinent for 4 weeks.MeasurementsFeasibility of introducing RPI into routine care; response to interactive messages and requests for the medication; rating of the helpfulness of RPI; self‐reported and carbon monoxide (CO)‐validated smoking status for up to 26 weeks.FindingsA text‐based RPI was easy to implement within the NHS SSS provided by specialist advisers, but enrolment of clients from services provided by a network of pharmacists was difficult because client contact details were often lacking. Where records of the number of people invited to RPI were available, 94% of eligible participants enrolled. The RPI was well received by both SSS clients and staff, with 70% (n = 63) of clients who completed follow‐up considering the intervention helpful. Eighty‐five per cent (n = 172) of clients responded to at least one of the nine interactive text messages. Sixty‐four clients (32% of the total, 47% of those we managed to contact) reported continuous abstinence at 6 months. Eighteen (9%) clients who relapsed to smoking used the RPI to re‐engage with the NHS SSS and 10 (5%) successfully re‐established abstinence.ConclusionsIn smokers attending National Health Service Stop Smoking Services who are abstinent 4 weeks after their quit date, a relapse prevention intervention based on SMS text messaging was well received, and can be implemented economically and rapidly. A controlled trial is needed to establish whether it has a significant impact on relapse.
Smokeless tobacco cessation in South Asian communities: a multi‐centre prospective cohort study
Authors: Croucher Ray , Shanbhag Siddharth , Dahiya Manu , Kassim Saba , Csikar Julia , Ross Louise 
Published: November 2012

AbstractAimTo evaluate smokeless tobacco cessation in communities of South Asian origin.DesignMulti‐centre prospective cohort study.SettingThree tobacco cessation services offering specialist smokeless tobacco cessation outreach clinic support to South Asians (Bangladeshi, Indian and Pakistani) resident in England.ParticipantsA total of 239 South Asian participants seeking to stop smokeless tobacco use between November 2010 and December 2011.MeasurementsSocio‐demographics, tobacco use and dependence, self‐reported abstinence at 4 weeks and satisfaction measures.FindingsParticipants' mean age was 45 [standard deviation (SD) = 13] years, were predominantly female (76%), of Bangladeshi origin (74%), either home carers (53%) or not working (29%). Sixty‐three per cent were recruited from community locations, 21% through a clinical contact and 16% through friends and family. Mean daily number of smokeless tobacco intakes was 10 (SD = 7) and the mean dependence score was 4.5 (SD = 1.9). Sixty‐three per cent of participants achieved continuous abstinence 4 weeks after quitting. Using nicotine replacement therapy (NRT) versus not using it [OR = 3.47, 95% confidence interval (CI): 1.25, 9.62] and below median (≤8) daily smokeless tobacco intakes (OR = 1.91, 95% CI: 1.07, 3.40) predicted successful abstinence.ConclusionSouth Asian smokeless tobacco users resident in England accessing services to help them stop appear to have short‐term success rates comparable with smokers attending stop‐smoking services, with higher success rates being reported by those using nicotine replacement therapy.
Do time‐lagged extinctions and colonizations change the interpretation of buffer strip effectiveness? – a study of riparian bryophytes in the first decade after logging
Authors: Hylander Kristoffer , Weibull Henrik 
Published: November 2012

SummaryThere is a risk that short‐term studies either underestimate disturbance effects because of time‐lagged responses, including both time‐lagged extinctions and colonizations, or overestimate them because of fast recovery.To evaluate the conservation effectiveness of tree group retention (in this case, buffer strips along streams), we studied the bryophyte community once prior to, and twice after logging, comparing one buffer and one clear‐cut plot (0·1 ha) in each of 13 riparian sites. We asked whether time‐lagged responses or recovery processes had dominated the period between two re‐inventories, 2·5 and 10·5 years after logging, focusing both on the whole community and on species of conservation concern.Although there were examples of recovering species in both clear‐cuts and buffer strips, the similarity in species composition to predisturbance conditions had decreased in the second re‐inventory. Even if the buffer strips displayed more time‐lagged colonizations and local extinctions over the later period compared to the clear‐cuts, the overall species composition in the buffer strips was still significantly more similar to the prelogging conditions than the clear‐cuts.The red‐listed species had mostly declined during the first period, and the number of red‐list species per plot (mostly species growing on dead wood) was rather stable at <20% of predisturbance levels in clear‐cuts and <60% in buffer strips in the last re‐inventory.Synthesis and applications. We show that most extinctions of red‐list species occurred soon after disturbance and that the conclusions drawn from a study carried out 2·5 years after the disturbance did not change profoundly 8 years later. Although the species composition in the buffer strips continued to change over time, sensitive species survived much better in buffer strips than in clear‐cuts, which supports the practice of retaining buffer strips for terrestrial species too. This knowledge should encourage managers to find ways of increasing the efficacy of this practice. One obvious measure could be to retain wider strips or implement other management practices that make the buffer strips less sensitive to wind, which will lead to higher tree retention to support a prelogging species composition.