bluuebunny/crossref_metadata_2025 huggingface dataset:
Claudin-2–deficient mice are defective in the leaky and cation-selective paracellular permeability properties of renal proximal tubules
Authors: Muto Shigeaki , Hata Masaki , Taniguchi Junichi , Tsuruoka Shuichi , Moriwaki Kazumasa , Saitou Mitinori , Furuse Kyoko , Sasaki Hiroyuki , Fujimura Akio , Imai Masashi , Kusano Eiji , Tsukita Shoichiro , Furuse Mikio
Published: April 2010

Claudin-2 is highly expressed in tight junctions of mouse renal proximal tubules, which possess a leaky epithelium whose unique permeability properties underlie their high rate of NaCl reabsorption. To investigate the role of claudin-2 in paracellular NaCl transport in this nephron segment, we generated knockout mice lacking
claudin-2
(

Cldn2
−/−

)

. The

Cldn2
−/−

mice displayed normal appearance, activity, growth, and behavior. Light microscopy revealed no gross histological abnormalities in the

Cldn2
−/−

kidney. Ultrathin section and freeze-fracture replica electron microscopy revealed that, similar to those of wild types, the proximal tubules of

Cldn2
−/−

mice were characterized by poorly developed tight junctions with one or two continuous tight junction strands. In contrast, studies in isolated, perfused S2 segments of proximal tubules showed that net transepithelial reabsorption of Na
+
, Cl
–
, and water was significantly decreased in

Cldn2
−/−

mice and that there was an increase in paracellular shunt resistance without affecting the apical or basolateral membrane resistances. Moreover, deletion of claudin-2 caused a loss of cation (Na
+
) selectivity and therefore relative anion (Cl
–
) selectivity in the proximal tubule paracellular pathway. With free access to water and food, fractional Na
+
and Cl
–
excretions in

Cldn2
−/−

mice were similar to those in wild types, but both were greater in

Cldn2
−/−

mice after i.v. administration of 2% NaCl. We conclude that claudin-2 constitutes leaky and cation (Na
+
)–selective paracellular channels within tight junctions of mouse proximal tubules.
Model-based method for transcription factor target identification with limited data
Authors: Honkela Antti , Girardot Charles , Gustafson E. Hilary , Liu Ya-Hsin , Furlong Eileen E. M. , Lawrence Neil D. , Rattray Magnus
Published: April 2010

We present a computational method for identifying potential targets of a transcription factor (TF) using wild-type gene expression time series data. For each putative target gene we fit a simple differential equation model of transcriptional regulation, and the model likelihood serves as a score to rank targets. The expression profile of the TF is modeled as a sample from a Gaussian process prior distribution that is integrated out using a nonparametric Bayesian procedure. This results in a parsimonious model with relatively few parameters that can be applied to short time series datasets without noticeable overfitting. We assess our method using genome-wide chromatin immunoprecipitation (ChIP-chip) and loss-of-function mutant expression data for two TFs, Twist, and Mef2, controlling mesoderm development in
Drosophila
. Lists of top-ranked genes identified by our method are significantly enriched for genes close to bound regions identified in the ChIP-chip data and for genes that are differentially expressed in loss-of-function mutants. Targets of Twist display diverse expression profiles, and in this case a model-based approach performs significantly better than scoring based on correlation with TF expression. Our approach is found to be comparable or superior to ranking based on mutant differential expression scores. Also, we show how integrating complementary wild-type spatial expression data can further improve target ranking performance.
Protein transduction from retroviral Gag precursors
Authors: Voelkel Christine , Galla Melanie , Maetzig Tobias , Warlich Eva , Kuehle Johannes , Zychlinski Daniela , Bode Juergen , Cantz Tobias , Schambach Axel , Baum Christopher
Published: April 2010

Retroviral particles assemble a few thousand units of the Gag polyproteins. Proteolytic cleavage mediated by the retroviral protease forms the bioactive retroviral protein subunits before cell entry. We hypothesized that this process could be exploited for targeted, transient, and dose-controlled transduction of nonretroviral proteins into cultured cells. We demonstrate that gammaretroviral particles tolerate the incorporation of foreign protein at several positions of their Gag or Gag-Pol precursors. Receptor-mediated and thus potentially cell-specific uptake of engineered particles occurred within minutes after cell contact. Dose and kinetics of nonretroviral protein delivery were dependent upon the location within the polyprotein precursor. Proteins containing nuclear localization signals were incorporated into retroviral particles, and the proteins of interest were released from the precursor by the retroviral protease, recognizing engineered target sites. In contrast to integration-defective lentiviral vectors, protein transduction by retroviral polyprotein precursors was completely transient, as protein transducing retrovirus-like particles could be produced that did not transduce genes into target cells. Alternatively, bifunctional protein-delivering particle preparations were generated that maintained their ability to serve as vectors for retroviral transgenes. We show the potential of this approach for targeted genome engineering of induced pluripotent stem cells by delivering the site-specific DNA recombinase, Flp. Protein transduction of Flp after proteolytic release from the matrix position of Gag allowed excision of a lentivirally transduced cassette that concomitantly expresses the canonical reprogramming transcription factors (Oct4, Klf4, Sox2, c-Myc) and a fluorescent marker gene, thus generating induced pluripotent stem cells that are free of lentivirally transduced reprogramming genes.
Transgenic ablation of doublecortin-expressing cells suppresses adult neurogenesis and worsens stroke outcome in mice
Authors: Jin Kunlin , Wang Xiaomei , Xie Lin , Mao Xiao Ou , Greenberg David A.
Published: April 2010

Injury stimulates neurogenesis in the adult brain, but the role of injury-induced neurogenesis in brain repair and recovery is uncertain. One strategy for investigating this issue is to ablate neuronal precursors and thereby prevent neurogenesis, but this is difficult to achieve in a specific fashion. We produced transgenic mice that express herpes simplex virus thymidine kinase (TK) under control of the promoter for doublecortin (Dcx), a microtubule-associated protein expressed in newborn and migrating neurons. Treatment for 14 days with the antiviral drug ganciclovir (GCV) depleted Dcx-expressing and BrdU-labeled cells from the rostral subventricular zone and dentate gyrus, and abolished neurogenesis and associated neuromigration induced by focal cerebral ischemia. GCV treatment of Dcx-TK transgenic, but not WT, mice also increased infarct size and exacerbated postischemic sensorimotor behavioral deficits measured by rotarod, limb placing, and elevated body swing tests. These findings provide evidence that injury-induced neurogenesis contributes to stroke outcome and might therefore be a target for stroke therapy.
Blocking of
Plasmodium
transmission by cooperative action of Cecropin A and Defensin A in transgenic
Aedes aegypti
mosquitoes
Authors: Kokoza Vladimir , Ahmed Abdouelaziz , Woon Shin Sang , Okafor Nwando , Zou Zhen , Raikhel Alexander S.
Published: April 2010

To overcome burden of mosquito-borne diseases, multiple control strategies are needed. Population replacement with genetically modified mosquitoes carrying antipathogen effector genes is one of the possible approaches for controlling disease transmission. However, transgenic mosquitoes with antipathogen phenotypes based on overexpression of a single type effector molecule are not efficient in interrupting pathogen transmission. Here, we show that co-overexpression of two antimicrobial peptides (AMP), Cecropin A, and Defensin A, in transgenic
Aedes aegypti
mosquitoes results in the cooperative antibacterial and anti
Plasmodium
action of these AMPs. The transgenic hybrid mosquitoes that overexpressed both Cecropin A and Defensin A under the control of the
vitellogenin
promoter exhibited an elevated resistance to
Pseudomonas aeruginosa
infection, indicating that these AMPs acted cooperatively against this pathogenic bacterium. In these mosquitoes infected with
P. gallinaceum
, the number of oocysts was dramatically reduced in midguts, and no sporozoites were found in their salivary glands when the mosquitoes were fed twice to reactivate transgenic AMP production. Infection experiments using the transgenic hybrid mosquitoes, followed by sequential feeding on naive chicken, and then naive wild-type mosquitoes showed that the
Plasmodium
transmission was completely blocked. This study suggests an approach in generating transgenic mosquitoes with anti
Plasmodium
refractory phenotype, which is coexpression of two or more effector molecules with cooperative action on the parasite.
Translating intentions into nutrition behaviors via planning requires self‐efficacy: Evidence from Thailand and Germany
Authors: Schwarzer Ralf , Richert Jana , Kreausukon Pimchanok , Remme Lena , Wiedemann Amelie U. , Reuter Tabea
Published: April 2010

A first step towards the improvement of daily dietary behaviors is forming an intention to change one's nutrition. However, an intention by itself is not sufficient for successful action. Rather, to translate intentions into behavior, careful planning is recommended. Thus, planning constitutes a mediator between the intention and the behavior. However, if a person lacks self‐efficacy, this mediation might fail. Previous research in Costa Rica and South Korea has identified perceived self‐efficacy as a moderator of the intention–planning–behavior relationship. To examine further the moderator role of self‐efficacy, two additional studies were designed in Thailand and Germany. Study 1 surveyed 1718 Thai university students in terms of a low‐fat diet; Study 2 surveyed 1140 German internet users in terms of their fruit and vegetable consumption at two measurement points in time, 6 months apart. Intentions served as predictor, planning as mediator, self‐efficacy as moderator, and behaviors as outcomes. First, intentions were translated into nutrition behaviors by planning. Second, self‐efficacy moderated this mediation in both studies: The strength of the mediated effect increased along with levels of self‐efficacy, even when accounting for baseline behaviors. For planning to mediate the intention–behavior relation, people must not harbor self‐doubts. If they lack self‐efficacy, intentions are not well translated into nutrition behavior through planning.
Negotiating the ‘Garibaldi moment’ in Newcastle-upon-Tyne (1854–1861)
Authors: Sutcliffe Marcella Pellegrino
Published: April 2010

The year of the Risorgimento, 1860, is associated with the ‘Garibaldi moment’, a time when the image of the radical revolutionary appeared to be ‘depoliticised’ in Britain. While recognising such a phenomenon, this article considers whether regional pockets escaped such a trend, analysing the case-study of Newcastle-upon-Tyne, where strong links between Garibaldi and local radicals coloured public perceptions of the Italian hero. By scrutinising the unfolding of the ‘Garibaldi moment’ in this context a complex picture emerges, showing that, far from being a unifying ‘depoliticised’ figure, Garibaldi was a source of divisions within Newcastle society. Crucial in this division was George Crawshay's challenge to the recruitment of a British Legion to follow Garibaldi. By looking at the provincial press and examining the local reception of a variety of entertainments, it is argued that, while political engagement drove the enthusiasm of radical audiences, fashionable shows–devoid of political content–could not rely on Newcastle ‘Garibaldimania’.
The Italian Communist Party, local government and the Cold War
Authors: Forlenza Rosario
Published: April 2010

The Italian national elections of 18 April 1948 handed power to the Christian Democratic Party. The Italian Communist Party had, however, gained significant municipal control in the local elections of 1946. For the Communists, the local level became the testing ground where administrative practices, political initiatives, social alliances and economic projects were developed. The leaders and the intellectuals worked to outline the cultural framework of a political project which could challenge national politics from town councils. Meanwhile, with a view to making gains in the local elections of 1951–1952, propaganda was used in an attempt to diffuse and proselytise municipal political programmes among different social classes in a divided socioeconomic environment.
Party organisational change in Italy (1991–2006)
Authors: Ignazi Piero , Bardi Luciano , Massari Oreste
Published: April 2010

This article analyses, adopting the well-known approach of Katz and Mair, the issue of organizational change within Italian political parties since 1990. In addition to an account of trends in membership, local units, finances, staff, and of changes in party statutes, the article aims at testing the widespread view in the literature that organizational resources–hence power–are becoming more and more concentrated in the hands of party and/or parliamentary leaders, and correspondingly that the territorial presence of parties is declining. The analysis of the change over time of Katz and Mair's party organisational ‘faces’ leads to the confirmation, to a large extent, of the overall hypothesis of a decline of the party at ground level, and a concentration of party resources in the central office, and above all in the party in public office.
‘The way we were’: the social construction of Italian security policy
Authors: Pirani Pietro
Published: April 2010

Italian security policy literature reveals, usually implicitly rather than explicitly, two distinct strains of analysis. One set of explanations, rooted in realist theory, views Italian foreign policy behaviour by reference to its power position. A second set of arguments, rooted in liberalism, assumes that policy-makers are ultimately influenced by domestic institutional factors in deciding foreign policy issues. The purpose of this article is to offer a theoretical contribution to the ongoing debate on continuity and change in Italian foreign policy. While neorealist and liberal theories have been widely used to explain the development of Italian international behaviour, neither approach has yet provided a full explanation of Italian security policy since the end of the Cold War. In contrast to these theories, it is argued that Italy has built its foreign policy on the basis of cultural considerations involving conflicting strategies of action.
Umberto Zanotti Bianco and the Mogadishu events of 1948
Authors: Ungari Andrea
Published: April 2010

Soon after the Second World War and the signing of the 1947 Peace Treaty, Italy was faced with the traumatic loss of its African colonial Empire, an Empire whose establishment had been one of the main objectives of the Fascist regime's foreign policy. This article analyses Anglo-Italian relations in the Somalian context, highlighting the contributions made by Fascism and by the anti-Italian policies of British troops to the tensions that were to lead to the tragic events of January 1948. Attention is focused on the diplomatic mission carried out by Umberto Zanotti Bianco, President of the Italian Red Cross, an important figure in Italian Liberalism. Zanotti Bianco was conscious of the need for Italy to rejoin the ‘club’ of democratic powers and, in accordance with the diplomatic strategy of Foreign Minister Carlo Sforza, he sought to reopen dialogue between Britain and Italy. The dispute between Italy and Britain brought about by the Mogadishu events and, more generally, by the Italian presence in Africa was soon brought to a close, due both to Zanotti Bianco's shrewd strategy and to the clear need for the Western Allies to strengthen De Gasperi's government on the eve of the decisive April 1948 elections.
Gramsci's unorthodox Marxism: political ambiguity and sociological relevance
Authors: Schecter Darrow
Published: April 2010

Gramsci's work continues to enjoy popularity amongst academics and activists. There is nonetheless a real question about the relevance of his central political ideas for the twenty-first century. This paper defends the thesis that Gramsci's humanism is part of a long tradition of political thought which dates back to Machiavelli, and that although this national-popular humanism is now outdated for reasons which are suggested in the writings and films of Pier Paolo Pasolini, there is also a sociological component to Gramsci's theorising that retains resonance today.
‘Policies Are Never Implemented, But Negotiated’: Analyzing Integration of Policies in Managing Water Resources in the Indian Himalayas Using a Bayesian Network
Authors: Saravanan V. S. , McDonald Geoffrey T. , Horen Basil van , Ip David
Published: April 2010

The paper contributes by analyzing nonlinear and complex integration of policies in framing a water management problem in a case study hamlet in the Indian Himalayas. It reveals that policies are never implemented, but integrated through the negotiation with other policies and socio-cultural settings in (re)shaping water resources management. It demonstrates the incremental and cumulative integration of policies that are formulated from different governance arrangements in (mis)managing water. In such a regime, the paper calls for statutory public actors to lay-out broad principles in their policy statements that allow multiple actors to debate and negotiate diverse alternatives in order to make the policy-making process integrative, adaptive, and dynamic.
Fiscal Balance: Environmental Taxes and Investments
Authors: Thampapillai Dodo J. , Xun Wu , Tan Seck L.
Published: April 2010

In this paper we develop a simple framework in macroeconomics for evaluating environmental investments that bear national significance. The framework rests on the concept of fiscal balance and the premise that environmental taxes must be returned towards restoring and/or enhancing environmental capital investments. We further illustrate that traditional frameworks in macroeconomics are not capable of evaluating the social desirability of environmental investments owing to the absence of environmental variables in these frameworks. The framework developed here shows that the recognition of environmental capital depreciation in macroeconomics permits the differentiation between various environmental investments in terms of their environmental impacts. These impacts are measured in terms of the costs of abating pollutants associated with climate change. The framework and its application are illustrated with reference to environmental investments in Vietnam.
The New Forest Legislation in Russia: The Leaseholders' Attitudes
Authors: Torniainen Tatu J. , Mashkina Olga V. , Saastamoinen Olli J. , Petrov Vladimir N.
Published: April 2010

The Russian forest sector has undergone significant institutional changes over its history. This is especially so during the last 15 years following market reforms including abolition of a central command economy. During this time the forest sector has performed poorly in comparison with other natural resource sectors in Russia. The problems were identified to be in the existing formal and informal institutions. In 2007, the new Forest Code was adopted and introduced several major changes in the formal institutional environment. The implementation of the Code constitutes a major challenge for the Russian forest policy. The perceptions and attitudes of the actors play a very important role in how the Code is going to be implemented. The role of these attitudes is analyzed by creating typologies of opinions towards the new Forest Code among the leaseholders in the Northwest Russian forest abundant regions, Karelia, Leningrad, and Archangel. Results indicate that differences in perceptions and attitudes may have different impacts on the law enforcement and further on the realization of forest policy.
Overcoming Obstacles to Collaborative Water Governance: Moving Toward Sustainability in New Zealand
Authors: Memon Ali , Weber Edward P.
Published: April 2010

Given that New Zealand has long been known as an innovative, effective leader in natural resource policy, the idea that a major region of the country is facing a water resource crisis will strike many as odd. Yet, much like the many areas of the world experiencing serious water resource management and allocation problems, current water use and development trends in Canterbury (South Island) since 1991 have resulted in the gradual depletion and overuse of key water resources. The regional governing authority, Environment Canterbury (ECAN), and many stakeholders recognize that the current top-down, hierarchical water resource policy and management initiatives are not working and are, in many instances, contributing to the very crisis they seek to avoid. Nor are they making headway toward their desired overarching goal of establishing a network of sustainable communities within the region. The research examines the daunting problem of water resource policy management in the Canterbury area, describes the many obstacles in the way of a collaborative approach to water resource sustainability, and uses lessons learned from the international literature on collaborative approaches to critically appraise the potential for the successful collaborative governance of water resources in the region, specifically for the purpose of engendering sustainable communities.
Technical Efficiency of Sawmilling and the Conservation of Natural Forests: Evidence from Sri Lanka
Authors: Gunatilake H. , Gopalakrishnan C.
Published: April 2010

Existing policy instruments for conserving tropical forests have shown limited success. This paper investigates the feasibility of improving the technical efficiency of the wood processing industry as an alternative approach to forest conservation, using sawmills in Sri Lanka as a case study. Improved wood processing efficiency decreases the volume of raw material (logs) required to produce a given quantity of processed wood products and, therefore, decreases the pressure on forests lands. A stochastic frontier production function was estimated to assess the technical efficiency of sawmilling in Sri Lanka. Given the considerable inefficiency found in sawmilling operations, current sawn wood output can be obtained with 28% less inputs. Compared with other policy measures, technical efficiency improvement has a potential to play a noteworthy role in conserving natural forests.
Indirect effect of IGF2 intron3 g.3072G>A mutation on prolificacy in sows
Authors: Stinckens A. , Mathur P. , Janssens S. , Bruggeman V. , Onagbesan O. M. , Schroyen M. , Spincemaille G. , Decuypere E. , Georges M. , Buys N.
Published: April 2010

A QTL located in the paternally expressed insulin‐like growth factor 2 (IGF2) gene is known to increase muscle growth and reduce fat deposition in pigs. This makes the QTL in IGF2 a good marker for use in pig breeding programmes. However, care has to be taken as it is postulated that increased leanness and lowered fat deposition may have a negative effect on the prolificacy and longevity of sows. Selection of sire and dam lines for different alleles of the mutation in the paternally imprinted IGF2 gene could actually provide a solution to this problem. Therefore, in this study, the effect of the IGF2 QTL on prolificacy‐related traits in sows was investigated. It was found that the paternal IGF2 wild‐type allele was associated with higher reproduction performance in the sow. Moreover, it was also examined whether the difference in prolificacy in sows could be a consequence of differential IGF2 expression in the ovarian follicles of the sow or whether it is mainly a secondary effect caused by differences in fatness traits. Therefore, IGF2 expression was measured in follicles of different sizes from sows with different genotypes for the paternal IGF2 allele. It was observed that, however, while the size of the follicles was associated with follicular IGF2 expression level, the IGF2 genotype was not. It could be concluded that the difference in prolificacy of sows with a different paternal IGF2 genotype could be a secondary effect, resulting from differences in fat deposition.
Risk of digoxin intoxication in heart failure patients exposed to digoxin–diuretic interactions: a population‐based study
Authors: Wang Meng‐Ting , Su Chen‐Yi , Chan Agnes L. F. , Lian Pei‐Wen , Leu Hsin‐Bang , Hsu Yu‐Juei
Published: April 2010

WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT

• Increased frequency of electrolyte abnormalities and cardiac arrhythmias among patients exposed to digoxin–diuretic interactions has been well‐documented in numerous descriptive studies.

• Nonetheless, a clear causal relationship has not been established in these studies.

WHAT THIS STUDY ADDS

• The risks of digoxin intoxication associated with use of digoxin in combination with any diuretic use, types of diuretics, combinations of diuretics, and individual diuretics were quantified using a population‐based nested case–control study design.

• The combined therapy of digoxin with any diuretic is associated with a 3.08‐fold increase in the risk of digoxin intoxication.

• Regarding diuretic class, the risk carried by loop diuretics is greater than that of thiazides or potassium–sparing diuretics, and the risk varies with different combinations of diuretic classes and individual diuretics.

AIMS

To quantify the digoxin intoxication risk associated with exposure to digoxin–diuretic interactions, and evaluate whether the risk varies by diuretic type, individually or in combination.

METHODS

This was a population‐based nested case–control study in which data from the National Health Insurance Research Database (NHIRD) in Taiwan were analysed.

RESULTS

The study cohort comprised 154 058 heart failure (HF) patients taking digoxin between 2001 and 2004, in whom digoxin intoxication requiring a hospitalization (ICD‐9 code 972.1) occurred in 595 cases. A total of 28 243 matched controls were also selected for analysis. Cases were 3.08 times (adjusted OR 3.08, 95% CI 2.50, 3.79) more likely to have been prescribed diuretic medication in the previous month than controls. Regarding the class of diuretics, loop diuretics carried the greatest risk (adjusted OR 2.97, 95% CI 2.35, 3.75), followed by thiazides (OR 2.36, 95% CI 1.70, 3.29) and potassium‐sparing diuretics (OR 1.72, 95% CI 0.83, 3.56). The risk was also observed to vary with different combinations of diuretics, and the loops/thiazides/potassium‐sparing diuretics combination carried the greatest risk (adjusted OR 6.85, 95% CI 4.93, 9.53). Among the individual diuretics examined, hydrochlorothiazide carried the greatest risk (adjusted OR 4.63, 95% CI 2.50, 8.57).

CONCLUSIONS

This study provided empirical evidence that digoxin–diuretic interactions increased the risk of hospitalization for digoxin intoxication in HF patients. The risk was particularly high for concomitant use of digoxin with a combination of loop diuretics, thiazide and potassium‐sparing diuretics. The combined use of digoxin and diuretics should be avoided if possible.
Host‐searching responses to herbivory‐associated chemical information and patch use depend on mating status of female solitary parasitoid wasps
Authors: KUGIMIYA SOICHI , SHIMODA TAKESHI , WAJNBERG ERIC , UEFUNE MASAYOSHI , TAKABAYASHI JUNJI
Published: April 2010

1. In a tritrophic interaction system consisting of plants, herbivores, and their parasitoids, chemicals released from plants after herbivory are known to play important roles for many female parasitoids to find their hosts efficiently. On the plant side, chemical information associated with herbivory can act as an indirect defence by attracting the natural enemies of the host herbivores.

2. However, mated and virgin females of haplodiploid parasitoids might not necessarily respond to such chemical cues in the same way. Since virgin females can produce only sons, they might refrain from searching for hosts to invest eggs until copulation, in order to produce both sexes.

3. Here, we investigated differential host‐searching behaviours shown by mated and virgin females in the solitary parasitoid wasp,Cotesia vestalis, in response to herbivory‐associated chemical information from cruciferous plants infested by their host larvae,Plutella xylostella.

4. Mated females showed a significantly higher flight preference for host‐infested plants over intact plants, while no preference was observed with virgin females. Mated females also showed more intensive antennal searching and ovipositor probing behaviours to leaf squares with wounds caused by hosts than did virgin females. Furthermore, mated females stayed longer in host patches with higher parasitism rates than virgin females.

5. These results indicate that mating status ofC. vestalisfemales clearly influences their host‐searching behaviour in response to herbivory‐associated chemical information and patch exploitation. Female parasitoids seem to forage for hosts depending on their own physiological condition in a tritrophic system.
Vertical fracture resistance of roots after ultrasonic removal of fractured instruments
Authors: Madarati A. A. , Qualtrough A. J. E. , Watts D. C.
Published: April 2010

Madarati AA, Qualtrough AJE, Watts DC. Vertical fracture resistance of roots after ultrasonic removal of fractured instruments. International Endodontic Journal, 43, 424–429, 2010.

Aims  To investigate ex vivo root resistance to vertical fracture after fractured instruments were ultrasonically removed from different locations in the root canal.

Materials and methods Fifty‐three canine roots were weighed and divided into four groups. Eight roots served as a control group in which canals were instrumented to a size F5‐ProTaper instrument. In the experimental groups, F5‐ProTaper fragments were fractured in the coronal, middle and apical one‐thirds, and then removed ultrasonically. The time required for removal was recorded. Roots were reweighed, and canals were shaped to a size F5‐ProTaper and filled with GuttaFlow. After incubation, roots underwent a vertical fracture test in which the force at fracture was recorded. The difference in root mass before and after treatment (fractured file removal or canal preparation) was calculated. Data were analysed using the Kruskal–Wallis, Mann–Whitney post‐hoc and regression tests at P < 0.05.

Results  The highest root‐mass loss was recorded when fragments were removed from the apical one‐third (46.04 mg) followed by the middle and coronal (27.7 and 13.5 mg, respectively); these differences were significant (P < 0.05). There were significant differences in the force required for vertical fracture amongst the experimental groups (P < 0.05) with the lowest mean force recorded in the apical‐third group (107.1 N) followed by the middle and coronal (152.6 and 283.3 N, respectively). The highest mean force was recorded in the control group (301.5 N) which was not significantly different from that in the coronal group (P = 1.00). A negative exponential correlation (r = 0.669) existed between the root‐mass loss and the force required to fracture the roots.

Conclusion  Whilst removal of fractured instruments from the coronal one‐third of the root canal can be considered as a safe procedure, removal from deeper locations renders the root less resistant to vertical fracture.
Fracture resistance of incisor teeth restored using fibre‐reinforced posts and threaded metal posts: effect of post length, location, pretreatment and cementation of the final restoration
Authors: Schmitter M. , Lippenberger S. , Rues S. , Gilde H. , Rammelsberg P.
Published: April 2010

Schmitter M, Lippenberger S, Rues S, Gilde H, Rammelsberg P. Fracture resistance of incisor teeth restored using fibre‐reinforced posts and threaded metal posts: effect of post length, location, pretreatment and cementation of the final restoration. International Endodontic Journal, 43, 436–442, 2010.

Objective  The hypothesis of this study was that the fracture load of incisor teeth restored using short, threaded, parallel‐sided posts (TMP) is, under special conditions, not inferior to that of teeth restored using long TMPs or fibre‐reinforced posts (FRP).

Methodology  Seventy‐two maxillary incisors and 72 mandibular incisors were collected. Sixty‐four in each group were root filled; in half of these FRPs were cemented, and in the other half TMPs were used. Half of the FRPs were pretreated; the others were not pretreated. In the TMP‐group, half of the teeth received a long post (10 mm), the other half a short post (3 mm). Crowns were fabricated and cemented with Ketac‐cem or Panavia. Eight maxillary incisors and eight mandibular incisors with intact natural crowns were used as control groups. All specimens were loaded until fracture.

Results  Fracture loads were higher for pretreated FRPs than for untreated FRPs. If the FRPs were not pretreated, fracture loads for maxillary incisors after use of short metal posts were significantly higher (248 N compared with 133 N, P = 0.027). Fracture loads for teeth restored using long TMPs were not higher than for teeth restored using short TMPs (277 N compared with 266 N). Fracture loads for mandibular incisors restored using long (10 mm) pretreated FRP were higher than for mandibular incisors restored using short (3 mm) metal posts (436 N compared with 285 N). Cementation of the crowns using an adhesive resin cement did not increase the fracture load for mandibular incisors, whereas for maxillary incisors, this cementation technique tended to increase fracture loads in teeth restored with FRP, although this increase was not significant at the P < 0.05 level (P = 0.06). In both groups, fracture loads were higher for mandibular incisors.

Conclusions  Short, threaded, parallel‐sided metal posts might be an alternative to fibre‐ reinforced posts for maxillary incisors, for teeth with short roots or when FRP cannot be pretreated.
Essential lysine residues within transmembrane helix 1 of diphtheria toxin facilitate COPI binding and catalytic domain entry
Authors: Trujillo Carolina , Taylor‐Parker Julian , Harrison Robert , Murphy John R.
Published: April 2010

The translocation of the diphtheria toxin catalytic domain from the lumen of early endosomes into the cytosol of eukaryotic cells is an essential step in the intoxication process. We have previously shown that the in vitro translocation of the catalytic domain from the lumen of toxin pre‐loaded endosomal vesicles to the external medium requires the addition of cytosolic proteins including coatomer protein complex I (COPI) to the reaction mixture. Further, we have shown that transmembrane helix 1 plays an essential, but as yet undefined role in the entry process. We have used both site‐directed mutagenesis and a COPI complex precipitation assay to demonstrate that interaction(s) between at least three lysine residues in transmembrane helix 1 are essential for both COPI complex binding and the delivery of the catalytic domain into the target cell cytosol. Finally, a COPI binding domain swap was used to demonstrate that substitution of the lysine‐rich transmembrane helix 1 with the COPI binding portion of the p23 adaptor cytoplasmic tail results in a mutant that displays full wild‐type activity. Thus, irrespective of sequence, the ability of transmembrane helix 1 to bind to COPI complex appears to be the essential feature for catalytic domain delivery to the cytosol.
Cellular Expression or Binding of desLys58‐β2 Microglobulin is not Dependent on the Presence of the Tri‐molecular MHC Class I Complex
Authors: Wang M. , Corlin D. B. , Heegaard N. H. H. , Claesson M. H. , Nissen M. H.
Published: April 2010

The monoclonal antibody 332‐01 is a newly developed antibody which specifically recognizes human desLys58‐β2 microglobulin (dβ2m). In the present study, we characterized the binding of 332‐01 to peripheral blood mononuclear cells (PBMC), a number of human leukaemic and monocytic cell lines, and β2m gene‐deleted murine lymphocytes. dβ2m was found to be expressed on non‐activated and activated monocytes. When cells were pre‐exposed to dβ2m, 332‐01 also bound to non‐activated T lymphocytes. dβ2m was expressed on the monocytic cell lines U937 and TIB‐202, and binding was significantly increased when cells were pre‐incubated with dβ2m and when TIB‐202 cells were exposed to lipopolysaccharide. dβ2m was also expressed on T leukaemic Jurkat cells as well as on low HLA‐expressing erythroleukaemic K562 cells. β2m gene‐deleted murine splenocytes only bound 332‐01 after pre‐exposure to dβ2m. Binding of 332‐01 antibody could not be displaced by addition of high concentrations of native β2m. In conclusion, our data indicate that dβ2m – in contrast to native β2m – binds to a hitherto unknown cell surface receptor independent of classical MHC class I molecules. As β2m has previously been shown to display biological activities such as the induction of both growth promotion and apoptosis, C1 complement activity, shown to mediate cleavage of β2m, could be involved in these processes.
Breaking B‐cell Tolerance and CTL Tolerance in three OVA‐transgenic Mouse Strains Expressing Different Levels of OVA
Authors: Steinaa L. , Rasmussen P. B. , Gautam A. , Mouritsen S.
Published: April 2010

It is of major importance to overcome the immunological tolerance in attempts to generate efficient tumour vaccines. Here, we describe induction of autoantibodies and self‐reactive CTL in three types of OVA‐transgenic mouse strains, RIP‐OVAlow, RIP‐mOVA and RIP‐OVAHI exhibiting varying levels of OVA expression and tolerance. This was achieved by immunizing with DNA constructs where a foreign T‐helper epitope, P30 from tetanus toxin, was inserted into the OVA sequence. OVA wild‐type DNA as well as the P30‐modified OVA DNA vaccines (OVA‐P30) were constructed and used for immunization in the OVA‐transgenic mouse strains as well as in control C57Bl/6 mice. The data show that insertion of a foreign T‐helper peptide (P30) in OVA is sufficient for breaking B‐cell tolerance in three different OVA‐transgenic mice strain. This approach is sufficient for induction of self‐reactive CTL in two of the three strains that expressed either a membrane‐bound form of OVA or a low amount of soluble OVA. It was not possible to induce CTL but still possible to induce autoantibodies in the strain that expressed a higher level of soluble OVA.
Macrophage Migration Inhibitory Factor Has a MHC class I‐Like Motif and Function
Authors: Gibbings D. J. , Ghetu A. F. , Dery R. , Befus A. D.
Published: April 2010

Macrophage migration inhibitory factor (MIF) is found in immune‐privileged sites and inhibits cytotoxicity mediated by CD3‐ve lymphokine‐activated killer cells (LAK). The mechanism by which MIF attenuates LAK cytotoxicity is unknown. We provide evidence that MIF has a major histocompatibility complex (MHC) class I‐like motif. A monoclonal antibody (OX18) that binds a conserved region of rat MHC class I proteins binds native MIF. Anti‐MIF polyclonal antibodies bind MHC class I. Epitope mapping suggests OX18 binds a loop of MHC class I bound by several receptors for MHC class I. A sequence (PRPEG) within the proposed OX18‐binding site on MHC class I exists with a short insertion in MIF. OX18 does not bind MIF that is denatured by SDS‐PAGE. This suggests the OX18 epitope is dependent on higher order structure in MIF. Interestingly, MIF inhibits binding of tetramers of MHC class I (H2Db) to LAK cells, suggesting it may bind to receptors for MHC class I. MIF may be an example where small regions of MHC class I are used by endogenous and viral proteins to control cytotoxicity mediated by immune cells.
Naturally Acquired Immunity and Reduced Susceptibility to falciparum Malaria in Two Subpopulations of Endemic Eastern India
Authors: Biswas S. , Seth R. K. , Tyagi P. K. , Sharma S. K. , Dash A. P.
Published: April 2010

This study was aimed to assess the prevalence of naturally acquired humoral immune responses and their association with reduced susceptibility to malaria in children and adults with differential clinical conditions from an Indian zone where malaria is endemic. The study was undertaken in an eastern province of India (Keonjhar, Orissa) in a group of 341 children (both younger and older) and 98 adults living in two different areas, Town area and Forest area. They were studied for their parasitological and immunological profiles. Sera from different age‐matched groups were screened by ELISA to measure IgG reactivities for characterizing humoral immune responses to the B‐cell epitopes of Plasmodium falciparum MSP1, AMA1, RAP1 and EBA175 peptides and P. falciparum‐infected erythrocyte lysate. In Town area, overall P. falciparum cases were 5.5%, whereas those in Forest area were 26.7%. We observed an age‐wise increasing trend of immunity in these two populations. It was also noticed that the frequency of responders to stage‐specific antigens was higher in individuals from the Town area where the frequency of malaria was lower. The naturally acquired humoral immune responses to different stage‐specific antigens of P. falciparum reflect the reduced risk of malaria in the study groups. The higher frequency of seroresponders showed correlation with lower risk of developing malaria.
Evaluation of a new Recombinant BCG which Contains Mycobacterial Antigen ag85B–mpt64190–198–mtb8.4 in C57/BL6 Mice
Authors: Qie Y. Q. , Wang J. L. , Zhu B. D. , Xu Y. , Wang Q. Z. , Chen J. Z. , Wang H. H.
Published: April 2010

Tuberculosis (TB) caused by Mycobacterium tuberculosis continues to be one of the major public health problems in the world. The eventual control of this disease will require the development of a safe and effective vaccine. Bacille Calmette‐Guerin (BCG), the only vaccine against TB, is not perfect for its limited ability to protect against the adult form of TB. Some improvements of TB vaccines relied to strengthening the immunogenicity and/or persistence of genetically modified recombinant BCG (rBCG) strain. Antigen 85B (Ag85B) and Mtb8.4 are importantly immunodominant antigens of M. tuberculosis, and both are very promising vaccine candidate molecules. MPT64190–198, is presented to CD8+ T cells during mycobacterial infections. In this study, we combined these above genes into one recombinant gene of ag85B–mpt64190–198–mtb8.4. Then we constructed the new rBCG containing this united gene. This rBCG can induce an increased Th1‐type immune response in mice, characterized by an elevated level of interferon‐γ in antigen‐stimulated splenocyte culture and a strong IgG2a antibody response. Also, it can elicit longer immune responses than BCG. The results show that this rBCG is a promising candidate for further study.
B‐cell Activating Factor of the Tumour Necrosis Factor Family Expression in Blood Monocytes and T Cells from Patients with Primary Sjögren’s Syndrome
Authors: Lavie F. , Miceli‐Richard C. , Ittah M. , Sellam J. , Gottenberg J.‐E. , Mariette X.
Published: April 2010

We investigated B‐cell activating factor of the tumour necrosis factor family (BAFF) level in peripheral blood mononuclear cells (PBMCs), monocytes and T cells from patients with primary Sjögren’s syndrome (pSS) and controls both ex vivo and in vitro after cytokine stimulation. PBMCs, monocytes and T cells were isolated from 15 patients with pSS and 17 controls. Cells were cultured alone or with interferon (IFN)α, IFNγ and interleukin 10 (IL‐10). T cells were stimulated with phytohaemagglutin and anti‐CD3. BAFF protein was assessed by enzyme‐linked immunosorbent assay. Ex vivo, no difference was observed in BAFF mRNA level in PBMCs and monocytes from patients and controls. Blood monocytes were the main cell type secreting BAFF both in patients and controls. In vitro, after IFNα stimulation, BAFF mRNA level was significantly higher in cells from patients than from controls (63.8 versus 20.7, P = 0.03). T cells from patients secreted a higher level of BAFF protein than those from healthy donor cells (17.4 versus 2.9 pg/ml, respectively, P = 0.04) but at a lower level than that from monocytes. Stimulation of T cells did not change BAFF secretion level. The induction of Th17 cells showed no increased BAFF expression. In conclusion, similar to epithelial cells, blood monocytes in patients with pSS show increased production of BAFF under IFNα, which confirms the involvement of IFNα in pSS. BAFF expression is also increased in blood T cells of such patients, independently of T‐cell stimulation.
Suppression of Allergic Inflammation by Allergen‐DNA‐modified Dendritic Cells Depends on the Induction of Foxp3+ Regulatory T Cells
Authors: Wu Kui , Bi Yuttian , Sun Kun , Xia Junbo , Wang Yan , Wang Changzheng
Published: April 2010

CD4+CD25+Foxp3+Regulatory T cells (Tregs) play important roles in regulating allergic inflammation. To analyse if allergen‐DNA‐modified dendritic cells (DC) can suppress allergic responses and what roles Treg cells play in DC‐based allergen‐specific immunotherapy. Immature DC were transfected with retrovirus encoding Der p2 DNA, and administered to mice that sensitized and challenged with Der p2 protein. After Treg cells were depleted with anti‐CD25 mAb, mice were re‐challenged to observe the airway inflammation, and Treg cells in spleen CD4+ T cells. And responses of spleen CD4+ T cells to Der p2 were determined. Co‐culture of naïve CD4+ T cells with allergen‐modified DC induced Foxp3+ Tregs. Sensitized and challenged mice developed allergic airway inflammation and Th2 responses, and decreased Foxp3+ Tregs. Treatment with allergen‐modified‐DC suppressed airway inflammation and Th2 responses, and increased IL‐10 and IFN‐γ production and Foxp3+ Tregs significantly; and eliminated the responses of CD4+ T cells to allergen. Administration of anit‐CD25 mAb eliminated all the effects of modified‐DC except for the increasing of IFN‐γ. Allergen‐modified DC can induce immune tolerance to allergens and reverse the established Th2 responses induced by allergen, with dependence on the induction of Foxp3+ Tregs.
Peripheral Blood CD14high CD16+ Monocytes are Main Producers of IL‐10
Authors: Skrzeczyńska‐Moncznik J. , Bzowska M. , Lo˝seke S. , Grage‐Griebenow E. , Zembala M. , Pryjma J.
Published: April 2010

Based on CD14 and CD16 expression, human peripheral blood monocytes (MO) can be divided into a major CD14high CD16− population and two minor CD14high CD16+ and CD14dim CD16+ subpopulations. CD14dim CD16+ MO are well characterized and regarded as pro‐inflammatory because upon stimulation produce TNF‐α but little, if any, IL‐10. By contrast, little is known about CD14high CD16+ MO. We investigated the surface expression of selected determinants by CD16+ MO subpopulations, cytokine production, phagocytosis and antigen presentation. We found that both CD16+ subpopulations had a higher expression of HLA‐DR, CD86, CD54 and a lower expression of CD64 than CD14high CD16− population. In addition, CD14high CD16+ MO showed a higher expression of CD11b and TLR4 than CD14dim CD16+ and CD14high CD16− subpopulations. CD14high CD16+ MO exhibited an increased phagocytic activity and a decreased antigen presentation in comparison with CD14dim CD16+. As expected, lipopolysaccharide (LPS)‐stimulated CD14dim CD16+ MO produced TNF‐α but little IL‐10. By contrast, LPS‐stimulated CD14high CD16+ subpopulation produced significantly more IL‐10 than CD14dim CD16+ and CD14high CD16− MO. In conclusion, our data show that human peripheral blood CD16+ MO are heterogeneous in function and consist of two subpopulations: CD14dim CD16+ pro‐inflammatory and CD14high CD16+ with anti‐inflammatory potential.