bluuebunny/crossref_metadata_2025 huggingface dataset:
In situ measurement of leaf chlorophyll concentration: analysis of the optical/absolute relationship
Authors: PARRY CHRISTOPHER , BLONQUIST J. MARK , BUGBEE BRUCE
Published: March 2014

In situ optical meters are widely used to estimate leaf chlorophyll concentration, but non‐uniform chlorophyll distribution causes optical measurements to vary widely among species for the same chlorophyll concentration. Over 30 studies have sought to quantify the in situ/in vitro (optical/absolute) relationship, but neither chlorophyll extraction nor measurement techniques for in vitro analysis have been consistent among studies. Here we: (1) review standard procedures for measurement of chlorophyll; (2) estimate the error associated with non‐standard procedures; and (3) implement the most accurate methods to provide equations for conversion of optical to absolute chlorophyll for 22 species grown in multiple environments. Tests of five Minolta (model SPAD‐502) and 25 Opti‐Sciences (model CCM‐200) meters, manufactured from 1992 to 2013, indicate that differences among replicate models are less than 5%. We thus developed equations for converting between units from these meter types. There was no significant effect of environment on the optical/absolute chlorophyll relationship. We derive the theoretical relationship between optical transmission ratios and absolute chlorophyll concentration and show how non‐uniform distribution among species causes a variable, non‐linear response. These results link in situ optical measurements with in vitro chlorophyll concentration and provide insight to strategies for radiation capture among diverse species.
The regulatory network of cluster‐root function and development in phosphate‐deficient white lupin (Lupinus albus) identified by transcriptome sequencing
Authors: Wang Zhengrui , Straub Daniel , Yang Huaiyu , Kania Angelika , Shen Jianbo , Ludewig Uwe , Neumann Günter
Published: March 2014

Lupinus albus serves as model plant for root‐induced mobilization of sparingly soluble soil phosphates via the formation of cluster‐roots (CRs) that mediate secretion of protons, citrate, phenolics and acid phosphatases (APases). This study employed next‐generation sequencing to investigate the molecular mechanisms behind these complex adaptive responses at the transcriptome level. We compared different stages of CR development, including pre‐emergent (PE), juvenile (JU) and the mature (MA) stages. The results confirmed that the primary metabolism underwent significant modifications during CR maturation, promoting the biosynthesis of organic acids, as had been deduced from physiological studies. Citrate catabolism was downregulated, associated with citrate accumulation in MA clusters. Upregulation of the phenylpropanoid pathway reflected the accumulation of phenolics. Specific transcript expression of ALMT and MATE transporter genes correlated with the exudation of citrate and flavonoids. The expression of transcripts related to nucleotide degradation and APases in MA clusters coincided with the re‐mobilization and hydrolysis of organic phosphate resources. Most interestingly, hormone‐related gene expression suggested a central role of ethylene during CR maturation. This was associated with the upregulation of the iron (Fe)‐deficiency regulated network that mediates ethylene‐induced expression of Fe‐deficiency responses in other species. Finally, transcripts related to abscisic acid and jasmonic acid were upregulated in MA clusters, while auxin‐ and brassinosteroid‐related genes and cytokinin receptors were most strongly expressed during CR initiation. Key regulations proposed by the RNA‐seq data were confirmed by quantitative real‐time polymerase chain reaction (RT‐qPCR) and some physiological analyses. A model for the gene network regulating CR development and function is presented.
Creating value while avoiding its destruction through R&D management and innovation
Authors: Gauthier Caroline
Published: March 2014

Value creation and capture remain a key but quite a challenging objective for many organizations. R&D and innovation management have to operate in a context of increasing complexity, particularly enriched by emerging technologies, new opportunities for transformation of business models, and multidimensional changes in market demands. This special section proposes new options to deal with this challenge. One paper contributes to the adoption of open business models by studying their antecedents and casual relationships. The three other papers propose using a different focus on value, avoiding its destruction by adopting different unusual mindsets; i.e. learning through failure, learning by deviating and investigating motivations for not participating in innovation communities.
Variability in coefficient of restitution in human facial skin
Authors: Anderson K. R. , Oleson J. J. , Anthony T. R.
Published: March 2014

Background

If particles rebound on human facial skin, they can be re‐entrained into the airflow and subsequently inhaled, increasing aspiration efficiency estimates. A realistic estimate of facial skin coefficient of restitution (CoR) is necessary to accurately model particle bounce. This study investigated the effects of sampling location, temperature, humidity levels, age, gender, and BMI on facial skin CoR.

Methods

A torsional ballistometer was used to measure facial CoR for 30 participants divided into three age groups (18–30, 31–40, and 41–65 years), at three temperatures and three humidity levels. The study was repeated twice: once in the late winter and once in the early summer to capture the seasonal variability.

Results

The CoR significantly varied across five facial locations, with values ranging from 0.55 to 0.75. Gender, sampling season and the interaction between sampling location and age were found to be significant, but changes in values were relatively small (0.05 at most) and are not considered practically significant.

Conclusion

CoR was non‐uniform across the face. The use of uniform CoR value as modeling input parameters or for mannequin facial surfaces in experimental wind tunnel studies may not be accurate due to the high variability in CoR between facial sampling locations.
Displacement Through Participation
Authors: Huisman Carla
Published: March 2014

Citizen participation is often regarded as a means to increase local democracy. Seldom is participation viewed as a means to legitimate disruptive practices of states. However, participation can become a tool for the effective implementation of policy rather than a means to enhance justice, if no power is transferred to citizens. Displacement in Amsterdam is a case in point. Here the local council together with housing corporations yearly forces over 2,000 households to leave their houses, a consequence of an ambitious policy of state‐led gentrification. Following Foucault, I explore the rationalities and techniques employed to ensure compliance. The promise of influence lures tenants into lengthy discussions with power holders. Investment choices are presented as objective facts and so provide a rationale for the disruptive interventions. Participation thus provides government a platform to impose its views in a context of severe power asymmetries, while alternatives are marginalised and dissent is disciplined.
Inserting Temporality into the Analysis of Displacement: Living Under the Threat of Displacement
Authors: Sakizlioğlu Bahar
Published: March 2014

Even though there is a growing literature on the extent and impacts of state‐led gentrification and displacement, there is little attention to the process of change in restructuring neighbourhoods and how residents experience the threat of displacement. How is it to live in a house that is to be demolished? How does a neighbourhood change once it is targeted for gentrification? How do the residents experience the threat of displacement before actual displacement takes place? This paper addresses this gap and investigates the trajectory of neighborhood change in neighbourhoods targeted for gentrification. Based on an ethnographic study of the renewal process inTarlabaşı /Istanbul, it discusses how residents live under the threat of displacement.
A Window on the (Changing) Neighbourhood: The Role of Pubs in the Contested Spaces of Gentrification
Authors: Ernst Olaf , Doucet Brian
Published: March 2014

This paper examines the effects of gentrification through the lens of the interactions and perceptions which can be found in local, neighbourhood pubs. By interviewing predominantly Dutch, non‐gentrifying customers in the rapidly gentrifying Indische Buurt neighbourhood in Amsterdam, we uncovered discourses which are both welcoming to, and cautious of the process. Three themes were examined: changes in the neighbourhood, changes in the role of pubs in daily life and changes in the interactions within pubs. In many respects, the process of gentrification is welcomed because it represents something ‘Dutch’ coming into the neighbourhood after years of immigration. Divisions between gentrifiers and non‐gentrifiers are not experienced as starkly as is often portrayed in the literature; our respondents tended to be much more ambivalent than other non‐gentrifying groups portrayed in studies elsewhere. This may be due to the more managed‐nature of Dutch gentrification. However, there is a sense that one's pub is impervious to the changes in the rest of the neighbourhood, a discourse which must be taken into account when drawing any long‐term conclusions from this study.
A Process of Change and a Changing Process: Introduction to the Special Issue on Contemporary Gentrification
Authors: Doucet Brian
Published: March 2014

Gentrification is a process of social and spatial change, but it is also a changing process. This special issue aims to better understand new forms of gentrification, policies and experiences which have emerged since the year 2000. Specific emphasis has been given to the Netherlands, a country where the strong role of the state and more than two decades of pro‐gentrification policy have created a unique context where gentrification is pursued, implemented and experienced in different ways than in the Anglo‐Saxon world. Research into Dutch gentrification has led to new theoretical insights in the past and the papers in this special issue should present international readers with new and alternative perspectives towards contemporary gentrification, thereby contributing to a wider understanding of the ‘geography of gentrification’. This introduction will examine new spatial and social manifestations of gentrification over the past decade, examine what binds them together as part of the gentrification process, introduce Dutch gentrification and outline the papers featured in this special issue.
Cutaneous legionellosis: case report and review of the medical literature
Authors: Padrnos L.J. , Blair J.E. , Kusne S. , DiCaudo D.J. , Mikhael J.R.
Published: March 2014

Discrete nodules developed on the leg of a 27‐year‐old immunosuppressed woman after an allogeneic stem cell transplant. Biopsy and culture grew Legionella pneumophila serogroup 8. On day 7 of azithromycin treatment, respiratory distress and abnormal liver transaminases developed, and the patient died on day 14. Review of the medical literature identified 19 reports of Legionella species‐associated skin or soft tissue infections (total of 20 patients, 13 with confirmed infection). Manifestations of the 13 confirmed cases included erythematous macular rash (n = 7), erythema after thoracentesis (n = 1), abscess formation (n = 4), respiratory symptoms (n = 6), and abnormal chest radiographs (n = 8). Six required surgical exploration and débridement, and 7 were immunocompromised. Rash and respiratory infection improved with antibiotics in 10, but 3 died. Immunosuppression may predispose transplant recipients to Legionella infections. Diagnostic biopsies may facilitate appropriate treatment.
Oxygen and pulse oximetry in childhood pneumonia: surveys of clinicians and student clinicians in Cambodia
Authors: Ginsburg Amy Sarah , Gerth‐Guyette Emily , Mollis Brenda , Gardner Michelle , Chham Samnang
Published: March 2014

Objective

To better understand the availability of oxygen and pulse oximetry, barriers to use, clinician perceptions and practices regarding their role in the management of childhood pneumonia, and the formal education and training regarding these technologies received by student clinicians in Cambodia.

Methods

In the clinician survey, we surveyed 81 clinicians practising at all national paediatric, provincial and district referral hospitals throughout Cambodia. Respondents were primarily physicians whose scope of practice included paediatrics, and most reported the presence of oxygen (93% (95% confidence interval (CI) [87, 98])) but less availability of pulse oximetry (51% (95% CI [39, 61])).

Results

Common barriers to use included a lack of policies and guidelines, as well as a lack of training. In the student clinician survey, 332 graduating medical and nursing students were surveyed, and most reported learning about oxygen (96% (95% CI [94, 98])) and pulse oximetry (72% (95% CI [67, 77])) during their training.

Conclusions

Data from both surveys indicate that despite their utility, oxygen and pulse oximetry may be underused in Cambodia. The reported barriers and perceptions of the tools indicate a clear role for improved training for clinicians and students on the use of oxygen and pulse oximetry, the value of oxygen and pulse oximetry for managing childhood pneumonia, and the need for improved policies and guidelines governing their use.
The interaction between malaria and human immunodeficiency virus infection in severely anaemic Malawian children: a prospective longitudinal study
Authors: Kyeyune Francis X. , Calis Job C. J. , Phiri Kamija S. , Faragher Brian , Kachala David , Brabin Bernard J. , van Hensbroek Michaël Boele
Published: March 2014

Objective

Malaria and human immunodeficiency virus (HIV) infection are co‐prevalent in sub‐Saharan Africa and cause severe anaemia in children. Interactions between these infections occur in adults, although these are less clear in children. The aim of study was to determine their interaction in a cohort of severely anaemic children.

Methods

Severely anaemic Malawian children were enrolled, tested for HIV and malaria, transfused and followed for 18 months for malaria incidence. Antiretrovirals were not widely available in Malawi during the study period.

Results

Of 381 children (haemoglobin <5 g/dl), 357 consented for HIV testing, 12.6% were HIV‐infected, and 59.5% had malaria parasitaemia. At enrolment, HIV‐infected children had similar malaria parasitaemia prevalence (59.1% vs. 58.7%; P = 0.96) and parasite density (geometric mean [parasites/μl] 6903 vs. 12417; P = 0.18) as HIV‐negative children. There were no differences in mean CD4%, or prevalence of severe immunosuppression, between those with and without malaria parasitaemia. Plasma viral load correlated negatively with log parasitaemia (r = −0.78; P = 0.01). During follow‐up, HIV‐infected children did not experience more frequent parasitaemias or symptomatic malaria episodes. Adjusted risk estimates (95% CI) for malaria parasitaemia in HIV‐infected children at 6 and 18 months follow‐up were 0.39 (0.13–1.14) and 0.40 (0.11–1.51), respectively.

Conclusions

Severely anaemic HIV‐infected children showed no increased susceptibility to asymptomatic or symptomatic malaria during or following their anaemic episode, although all experienced lower parasite prevalence during follow‐up. This contrasts with data in adults and may relate to the malaria immunity of young children which is insufficiently developed to be impaired by HIV. The negative correlation between viral load and malaria parasitaemia remains unexplained.
Patterns of divergence of a large family of nodule cysteine‐rich peptides in accessions of Medicago truncatula
Authors: Nallu Sumitha , Silverstein Kevin A. T. , Zhou Peng , Young Nevin D. , VandenBosch Kathryn A.
Published: March 2014

The nodule cysteine‐rich (NCR) groups of defensin‐like (DEFL) genes are one of the largest gene families expressed in the nodules of some legume plants. They have only been observed in the inverted repeat loss clade (IRLC) of legumes, which includes the model legume Medicago truncatula. NCRs are reported to play an important role in plant–microbe interactions. To understand their diversity we analyzed their expression and sequence polymorphisms among four accessions of M. truncatula. A significant expression and nucleotide variation was observed among the genes. We then used 26 accessions to estimate the selection pressures shaping evolution among the accessions by calculating the nucleotide diversity at non‐synonymous and synonymous sites in the coding region. The mature peptides of the orthologous NCRs had signatures of both purifying and diversifying selection pressures, unlike the seed DEFLs, which predominantly exhibited purifying selection. The expression, sequence variation and apparent diversifying selection in NCRs within the Medicago species indicates rapid and recent evolution, and suggests that this family of genes is actively evolving to adapt to different environments and is acquiring new functions.
Digital imaging analysis to assess scar phenotype
Authors: Smith Brian J. , Nidey Nichole , Miller Steven F. , Moreno Uribe Lina M. , Baum Christian L. , Hamilton Grant S. , Wehby George L. , Dunnwald Martine
Published: March 2014

In order to understand the link between the genetic background of patients and wound clinical outcomes, it is critical to have a reliable method to assess the phenotypic characteristics of healed wounds. In this study, we present a novel imaging method that provides reproducible, sensitive, and unbiased assessments of postsurgical scarring. We used this approach to investigate the possibility that genetic variants in orofacial clefting genes are associated with suboptimal healing. Red‐green‐blue digital images of postsurgical scars of 68 patients, following unilateral cleft lip repair, were captured using the 3dMD imaging system. Morphometric and colorimetric data of repaired regions of the philtrum and upper lip were acquired using ImageJ software, and the unaffected contralateral regions were used as patient‐specific controls. Repeatability of the method was high with intraclass correlation coefficient score > 0.8. This method detected a very significant difference in all three colors, and for all patients, between the scarred and the contralateral unaffected philtrum (p ranging from 1.20−05 to 1.95−14). Physicians’ clinical outcome ratings from the same images showed high interobserver variability (overall Pearson coefficient = 0.49) as well as low correlation with digital image analysis results. Finally, we identified genetic variants in TGFB3 and ARHGAP29 associated with suboptimal healing outcome.
Glycation of extracellular matrix proteins impairs migration of immune cells
Authors: Haucke Elisa , Navarrete‐Santos Alexander , Simm Andreas , Silber Rolf‐Edgar , Hofmann Britt
Published: March 2014

The immune response during aging and diabetes is disturbed and may be due to the altered migration of immune cells in an aged tissue. Our study should prove the hypothesis that age and diabetes‐related advanced glycation end products (AGEs) have an impact on the migration and adhesion of human T‐cells. To achieve our purpose, we used in vitro AGE‐modified proteins (soluble albumin and fibronectin [FN]), as well as human collagen obtained from bypass graft. A Boyden chamber was used to study cell migration. Migrated Jurkat T‐cells were analyzed by flow cytometry and cell adhesion by crystal violet staining. Actin polymerization was determined by phalloidin‐Alexa‐fluor 488‐labeled antibody and fluorescence microscopy. We found that significantly fewer cells (50%, p = 0.003) migrated through methylglyoxal modified FN. The attachment to FN in the presence of AGE‐bovine serum albumin (BSA) was also reduced (p < 0.05). In ex vivo experiments, isolated collagen from human vein graft material negatively affected the migration of the cells depending on the grade of AGE modification of the collagen. Collagen with a low AGE level reduced the cell migration by 30%, and collagen with a high AGE level by 60%. Interaction of the cells with an AGE‐modified matrix, but not with soluble AGEs like BSA‐AGE per se, was responsible for a disturbed migration. The reduced migration was accompanied by an impaired actin polymerization. We conclude that AGEs‐modified matrix protein inhibits cell migration and adhesion of Jurkat T‐cells.
Clinical effect of bovine amniotic membrane and hydrocolloid on wound by laser treatment: Prospective comparative randomized clinical trial
Authors: Min Seonguk , Yoon Ji Young , Park Seon Yong , Kwon Hyuck Hoon , Suh Dae Hun
Published: March 2014

Bovine amniotic membrane (BAM) has been regarded as an ideal dressing material because it accelerates epithelization and has anti‐inflammatory, anti‐angiogenic, and strong analgesic effects. To evaluate the clinical effects of BAM and compare them to that of hydrocolloid dressings on wounds created by ablative laser treatments, 49 subjects with nevi or scars requiring ablative laser treatment were evaluated. To compare efficacy, we divided the body into six areas and included patients with two or more similar skin lesions in the same body area. After ablative laser treatments, BAM and hydrocolloid dressing were applied to the wounds with random allocation. Clinical assessments were performed at baseline, 1, 4, 6, 8, 11, and 13 days after treatment. Histologic changes were assessed by skin biopsy. BAM treatment induced faster epithelization than hydrocolloid treatment (6.7 vs. 9.2 days). Erythema and oozing faded more quickly, and the satisfaction score was higher in BAM‐treated sites than it was in hydrocolloid‐treated sites, without severe adverse effects. Histologic analysis confirmed epithelization and immunohistochemistry revealed different growth factor profiles between the two treatment modalities. BAM benefits wound healing following ablative laser treatment.
Time course of lewisite‐induced skin lesions and inflammatory response in the SKH‐1 hairless mouse model
Authors: Nguon Nina , Cléry‐Barraud Cécile , Vallet Virginie , Elbakdouri Nacéra , Wartelle Julien , Mouret Stéphane , Bertoni Marine , Dorandeu Frédéric , Boudry Isabelle
Published: March 2014

Data on the toxicity of lewisite (L), a vesicant chemical warfare agent, are scarce and conflicting, and the use of the specific antidote is not without drawbacks. This study was designed to evaluate if the SKH‐1 hairless mouse model was suitable to study the L‐induced skin injuries. We studied the progression of lesions following exposure to L vapors for 21 days using paraclinical parameters (color, transepidermal water loss (TEWL), and biomechanical measurements), histological assessments, and biochemical indexes of inflammation. Some data were also obtained over 27 weeks. The development of lesions was similar to that reported in other models. The TEWL parameter appeared to be the most appropriate index to follow their progression. Histological analysis showed inflammatory cell infiltration and microvesications at day 1 and a complete wound closure by day 21. Biochemical studies indicated a deregulation of the levels of several cytokines and receptors involved in inflammation. An increase in the quantity of pro‐matrix metalloproteinases 2 and 9 was shown as observed in other models. This suggests that the SKH‐1 mouse model is relevant for the investigation of the physiopathological process of skin lesions induced by L and to screen new treatment candidates.
Application of stems cells in wound healing—An update
Authors: Teng Miao , Huang Yuesheng , Zhang Hengshu
Published: March 2014

Wound healing is a complex but well‐orchestrated tissue repair process composed of a series of molecular and cellular events conducted by various types of cells and extracellular matrix. Despite a variety of therapeutic strategies proposed to accelerate the healing of acute and/or chronic wounds over the past few decades, effective treatment of chronic nonhealing wounds still remains a challenge. Due to the recent advances in stem cell research, a dramatic enthusiasm has been drawn to the application of stem cells in regenerative medicine. Both embryonic and adult stem cells have prolonged self‐renewal capacity and are able to differentiate into various tissue types. Nevertheless, use of embryonic stem cells is limited, owing to ethical concerns and legal restrictions. Adult stem cells, which could be isolated from bone marrow, umbilical cord blood, adipose tissue, skin and hair follicles,are being explored extensively to facilitate the healing of both acute and chronic wounds. The current article summarizes recent research on various types of stem cell‐based strategies applied to improve wound healing. In addition, future directions of stem cell‐based therapy in wound healing have also been discussed. Finally, despite its apparent advantages, limitations and challenges of stem cell therapy are discussed.
Effects of reduction in the alpha‐gal antigen on bony union: a model of xenobone graft using GalT knockout mouse
Authors: Park Moon Seok , Kim Tae Gyun , Lee Kyoung Min , Chung Chin Youb , Kwon Soon‐Sun , Yoon Il‐Hee , Park Chung‐Gyu
Published: March 2014

Background

Among the bone graft sources used currently, the availability of autografts is limited and allografts are expensive. Therefore, xenobone grafts have drawn attention as a new source of bone grafts, although immunologic rejection issues are unresolved. This study used a GalT knockout mouse model to investigate the effects of reducing the alpha‐gal epitope using alpha‐galactosidase on the union of porcine xenobone grafts.

Methods

Sixty‐eight alpha‐gal knockout C57/BL6 mice and eight wild‐type mice were used. The mice were divided into five groups: In group 1 (26 alpha‐gal knockout mice), an alpha‐galactosidase‐treated porcine xenograft was transplanted into the mouse femur to reduce antigenicity, and intramedullary fixation was performed. In group 2 (26 alpha‐gal knockout mice), a non‐treated porcine xenobone graft was performed. In group 3 (eight alpha‐gal knockout C57/BL6 mice), syngenic bone grafts were performed. In group 4 (eight wild‐type C57/BL6 mice), syngenic bone grafts were performed. In group 5 (eight C57/BL6 alpha‐gal knockout mice), a bone defect model was obtained by maintaining the gap of the osteotomy site. Groups 3, 4, and 5 were used for positive and negative control groups. Qualitative immunohistochemical analysis of the porcine bone was performed to detect the presence of the alpha‐gal epitope in groups 1 and 2. The concentration of the anti‐alpha‐gal antibody was evaluated using a quantitative enzyme‐linked immunosorbent assay (ELISA) at the time of sacrifice (3, 4, and 5 weeks after the operation). Histologic and radiologic results (Goldberg method) for the bone union were compared.

Results

The qualitative immunohistochemical analysis showed that the alpha‐gal epitope was reduced when xenobone grafts were treated with alpha‐galactosidase. Compared with group 2, group 1 showed a low anti‐alpha‐gal antibody concentration in the ELISA results. In group 2, the anti‐alpha‐gal antibody concentration increased with time. Group 1 showed significantly better histologic union than group 2, but the amount of radiologic union was similar in the two groups.

Conclusions

Alpha‐galactosidase treatment of a porcine xenobone graft can reduce the alpha‐gal epitope. This reduction in the antigen could significantly reduce the humoral immune response to the alpha‐gal antigen in C57/BL6 alpha‐gal knockout mice, leading to significant improvements in histologic union. This study provides a relevant GalT knockout mouse model for detecting the effects of alpha‐gal epitope reduction by alpha‐galactosidase on the union of porcine xenobone grafts.
Pig‐to‐baboon liver xenoperfusion utilizing GalTKO.hCD46 pigs and glycoprotein Ib blockade
Authors: LaMattina John C. , Burdorf Lars , Zhang Tianshu , Rybak Elana , Cheng Xiangfei , Munivenkatappa Raghava , Salles Isabelle I. , Broos Katleen , Sievert Evelyn , McCormick Brian , Decarlo Marc , Ayares David , Deckmyn Hans , Azimzadeh Agnes M. , Pierson Richard N. , Barth Rolf N.
Published: March 2014

Background

Although transplantation of genetically modified porcine livers into baboons has yielded recipient survival for up to 7 days, survival is limited by profound thrombocytopenia, which becomes manifest almost immediately after revascularization, and by subsequent coagulopathy. Porcine von Willebrand's factor (VWF), a glycoprotein that adheres to activated platelets to initiate thrombus formation, has been shown to constitutively activate human platelets via their glycoprotein Ib (GPIb) receptors. Here, we report our pig‐to‐primate liver xenoperfusion model and evaluate whether targeting the GPIb‐VWF axis prevents platelet sequestration.

Methods

Twelve baboons underwent cross‐circulation with the following extracorporeal livers: one allogeneic control with a baboon liver, 4 xenogeneic controls with a GalTKO.hCD46 pig liver, 3 GalTKO.hCD46 pig livers in recipients treated with αGPIb antibody during perfusion, and 4 GalTKO.hCD46 pig livers pre‐treated with D‐arginine vasopressin (DDAVP) in recipients treated with αGPIb antibody during perfusion.

Results

All perfused livers appeared grossly and macroscopically normal and produced bile. Xenograft liver perfusion experiments treated with αGPIb antibody may show less platelet sequestration during the initial 2 h of perfusion. Portal venous resistance remained constant in all perfusion experiments. Platelet activation studies demonstrated platelet activation in all xenoperfusions, but not in the allogeneic perfusion.

Conclusion

These observations suggest that primate platelet sequestration by porcine liver and the associated thrombocytopenia are multifactorial and perhaps partially mediated by a constitutive interaction between porcine VWF and the primate GPIb receptor. Control of platelet sequestration and consumptive coagulopathy in liver xenotransplantation will likely require a multifaceted approach in our clinically relevant perfusion model.
Anti‐non‐Gal‐specific combination treatment with an anti‐idiotypic Ab and an inhibitory small molecule mitigates the xenoantibody response
Authors: Stewart John M. , Tarantal Alice F. , Chen Yan , Appleby Nancy C. , Fuentes Tania I. , Lee C. Chang I. , Salvaris Evelyn J. , d'Apice Anthony J. F. , Cowan Peter J. , Kearns‐Jonker Mary
Published: March 2014

Background

B‐cell depletion significantly extends survival of α‐1,3‐galactosyltranferase knockout (GTKO) porcine organs in pig‐to‐primate models. Our previous work demonstrated that the anti‐non‐Gal xenoantibody response is structurally restricted. Selective inhibition of xenoantigen/xenoantibody interactions could prolong xenograft survival while preserving B‐cell‐mediated immune surveillance.

Methods

The anti‐idiotypic antibody, B4N190, was selected from a synthetic human phage display library after enrichment against a recombinant anti‐non‐Gal xenoantibody followed by functional testing in vitro. The inhibitory small molecule, JMS022, was selected from the NCI diversity set III using virtual screening based on predicted xenoantibody structure. Three rhesus monkeys were pre‐treated with anti‐non‐Gal‐specific single‐chain anti‐idiotypic antibody, B4N190. A total of five monkeys, including two untreated controls, were then immunized with GTKO porcine endothelial cells to initiate an anti‐non‐α‐1,3‐Gal (non‐Gal) xenoantibody response. The efficacy of the inhibitory small molecule specific for anti‐non‐Gal xenoantibody, JMS022, was tested in vitro.

Results

After the combination of in vivo anti‐id and in vitro small molecule treatments, IgM xenoantibody binding to GTKO cells was reduced to pre‐immunization levels in two‐thirds of animals; however, some xenoantibodies remained in the third animal. Furthermore, when treated with anti‐id alone, all three experimental animals displayed a lower anti‐non‐Gal IgG xenoantibody response compared with controls. Treatment with anti‐idiotypic antibody alone reduced IgM xenoantibody response intensity in only one of three monkeys injected with GTKO pig endothelial cells. In the one experimental animal, which displayed reduced IgM and IgG responses, select B‐cell subsets were also reduced by anti‐id therapy alone. Furthermore, natural antibody responses, including anti‐laminin, anti‐ssDNA, and anti‐thyroglobulin antibodies were intact despite targeted depletion of anti‐non‐Gal xenoantibodies in vivo indicating that selective reduction of xenoantibodies can be accomplished without total B‐cell depletion.

Conclusions

This preliminary study demonstrates the strength of approaches designed to selectively inhibit anti‐non‐Gal xenoantibody. Both anti‐non‐Gal‐specific anti‐idiotypic antibody and small molecules can be used to selectively limit xenoantibody responses.
Development of a High-Pressure, High-Temperature, Optically Accessible Continuous-Flow Vessel for Fuel-Injection Experiments
Authors: James Kemar C. , Wang Jin , Maynard Michael C. , Morris Zackery B. , Fisher Brian T.
Published: March 2014

A vessel has been designed for nonreacting fuel-injection experiments with continuous flow of sweep gas at pressures up to 1380 kPa and temperatures up to 200 °C. Four orthogonal windows provide optical access for high-speed spray-visualization using a fast-pulsed light emitting diode (LED) and a high-speed camera. Initial experiments have been conducted to determine spray characteristics of n-heptane. At room conditions, liquid length and cone angle were 170 mm and 14.5 deg, respectively. With air flow in the chamber at 690 kPa and 100 °C, liquid length was considerably shorter at 92 mm and cone angle was wider at 16.5 deg.
Validation of a Three-Dimensional Internal Nozzle Flow Model Including Automatic Mesh Generation and Cavitation Effects
Authors: Zhao Hongwu , Quan Shaoping , Dai Meizhong , Pomraning Eric , Senecal P. K. , Xue Qingluan , Battistoni Michele , Som Sibendu
Published: March 2014

Fuel injectors often experience cavitation due to regions of extremely low pressure. In this work, a cavitation modeling method is implemented in the CONVERGE computational fluid dynamics (CFD) code in order to model the flow in fuel injectors. The CONVERGE code includes a Cartesian mesh based flow solver. In this solver, a volume of fluid (VOF) method is used to simulate the multiphase flow. The cavitation model is based on a flash-boiling method with rapid heat transfer between the liquid and vapor phases. In this method, a homogeneous relaxation model is used to describe the rate at which the instantaneous quality, the mass fraction of vapor in a two-phase mixture, will tend towards its equilibrium value. The model is first validated with the nozzle flow case of Winklhofer by comparing the mass flow rate with experimentally measured values at different outlet pressures. The cavitation contour shape is also compared with the experimental observations. Flow in the Engine Combustion Network Spray-A nozzle configuration is simulated. The mesh dependency is also studied in this work followed by validation against discharge coefficient data. Finally, calculations of a five-hole injector, including moving needle effects, are compared to experimental measurements.
Constructal Design of Convective Y-Shaped Cavities by Means of Genetic Algorithm
Authors: Lorenzini G. , Biserni C. , Estrada E. D. , Isoldi L. A. , dos Santos E. D. , Rocha L. A. O.
Published: March 2014

In the present work constructal design is employed to optimize the geometry of a convective, Y-shaped cavity that intrudes into a solid conducting wall. The main purpose is to investigate the influence of the dimensionless heat transfer parameter a over the optimal geometries of the cavity, i.e., the ones that minimize the maximum excess of temperature (or reduce the thermal resistance of the solid domain). The search for the best geometry has been performed with the help of a genetic algorithm (GA). For square solids (H/L = 1.0) the results obtained with an exhaustive search (which is based on solution of all possible geometries) were adopted to validate the GA method, while for H/L ≠ 1.0 GA is used to find the best geometry for all degrees of freedom investigated here: H/L, t1/t0, L1/L0, and α (four times optimized). The results demonstrate that there is no universal optimal shape that minimizes the thermal field for all values of a investigated. Moreover, the temperature distribution along the solid domain becomes more homogeneous with an increase of a, until a limit where the configuration of “optimal distribution of imperfections” is achieved and the shape tends to remain fixed. Finally, it has been highlighted that the GA method proved to be very effective in the search for the best shapes with the number of required simulations much lower (8 times for the most difficult situation) than that necessary for exhaustive search.
The Failure Behavior of Geometrically Asymmetric Metal Foam Core Sandwich Beams Under Three-Point Bending
Authors: Zhang Jianxun , Qin Qinghua , Ai Weilong , Li Huimin , Wang T. J.
Published: March 2014

The failure behavior of geometrically asymmetric sandwich beams with a metal foam core is analytically and experimentally investigated. New initial failure modes of the asymmetric sandwich beams are observed under three-point bending, i.e., face yield, face wrinkling, core shear A, core shear AB, core shear A-AB, and indentation. It is shown that the initial failure modes of sandwich beams depend on the span of the beam, the thicknesses of top and bottom face sheets, core height and material properties. We derived the analytical formulae for the initial failure loads and then constructed the initial failure mechanism maps for the geometrically asymmetric sandwich beams. It is shown that the analytically predicted initial failure mechanism maps are in good agreement with the experimental results, which are clearly different from the symmetric sandwich beams. As a preliminary application, the minimum weight designs are presented for asymmetric metal sandwich beams.
Fish bone perforation of the terminal ileum presenting as acute appendicitis
Authors: Saunders David , Jones Michael , Kaushik Monika , Thomas William Michael
Published: March 2014

We report a case of a bowel perforation due to a fish bone that presented as an acute abdomen. This patient's gastrointestinal perforation was treated with laparoscopic and open technique. Diagnosis can be difficult as foreign body bowel perforation can mimic other causes of acute abdomen. Diagnosis is still most commonly made intraoperatively. Laparoscopy proved useful in this case as it allowed the most appropriate surgical approach to be made.
ONLINE REPORT IN REAL TIME FROM THE NATIONAL PROSTATE CANCER REGISTER (NPCR) OF SWEDEN, A NEW AND EFFICIENT TOOL FOR QUALITY ASSURANCE
Authors: Stattin Pär , Sandin Fredrik , Örtqvist David , Damber Lena , Holmberg Erik , Cederberg Håkan , Lambe Mats
Published: March 2014

Introduction

Traditionally data in The Swedish Cancer register, The Patient Register and other health care registers have been characterized by a very high capture rate but a very long time between date of reported event and final report. However for quality assurance a rapid ascertainment and reporting is crucial.

Methods

We developed an online report in real time in INCA, a software for Internet Based Cancer Registration, with graphical views, developed in R, exactly identical to those used in the NPCR annual report (www.npcr.se/rapporter).

Results

The user can assess data for his/her own department, and compare with all 21 counties in Sweden, and mean for the nation for procedures and outcomes in real time. These data include waiting times between referral and first consultation, time between biopsy procedure and cancer information (Figure 1), selection of treatment, surgical outcome (positive margins) and many other pertinent aspects of cancer care. Data were made available in October 2013 for clinicians.

Discussion

These online data can be used for quality assurance, quality improvement and bench marking. The real time reporting system increases the need for rapid registration of data in NPCR in order to make optimal use of the system.

Figure 1

Waiting times in own hospital (red) and all counties (blue) and mean for nation (“riket” yellow)

Declaration of competing interests

This research was funded by the Swedish Research Council.
DOES PAY FOR PERFORMANCE IN HOSPITALS SAVE LIVES?
Authors: Roland Martin , Sutton Matt , Boaden Ruth , Macdonald Ruth
Published: March 2014

Introduction

Pay for performance is increasingly used as a way of improving the quality of medical care. We previously showed that a pay for performance scheme targeting a range of processes measures in hospitals in the North West of England was associated with a substantial reduction in mortality for pneumonia, myocardial infarction and heart failure equivalent to 890 fewer deaths (Sutton et al. Reduced Mortality with Hospital Pay for Performance in England. New England Journal of Medicine 2012;367:1821–28). This analysis only assessed mortality in the first 18 months after introduction of the scheme. We now report mortality outcomes at 42 months to see whether the effect was sustained.

Methods

Difference-in-differences regression analysis based on mortality for 230,985 patients admitted with pneumonia, myocardial infarction and heart failure to incentivised hospitals 18 months before and 42 months after the introduction of the program. These were compared with mortality in the following control groups: 1,260,545 patients admitted for the same three conditions to all 132 other hospitals in England, 50,400 patients admitted for six non-incentivised conditions to the incentivised group of hospitals and 285,301 patients admitted for non-incentivised conditions to all other hospitals in England. Analyses were adjusted for differences in age, gender, primary diagnosis, co-morbidities, type of admission, and location from which the patient was admitted.

Results

Preliminary analyses suggest that the gains in mortality seen 18 months after the introduction of the pay for performance programme were not sustained at 42 months.

Discussion

Pay for performance schemes remain controversial, and there are many unanswered questions about how and when they work. Our previous analyses were important because the incentive scheme that was introduced (Premier HQID) had no impact on mortality when introduced in the US, but appeared to have a substantial impact on mortality when introduced in the UK. However, our long term analyses suggest that these improvements were not sustained. We will comment on a number of possible reasons for the observed effects. One factor is that during the study period, the financial incentives changed from being bonuses to penalties for hospitals in the scheme.

Declaration of competing interests

None.
Sequence analysis of single-copy genes in two wild olive subspecies: nucleotide diversity and potential use for testing admixture
Authors: Besnard G. , El Bakkali A.
Published: March 2014

The wild olive distribution extends from the Mediterranean region to south Asia and Austral Africa. The species is also invasive, particularly in Australia. Here, we investigated the sequence variation at five nuclear single-copy genes in 41 native and invasive accessions of the Mediterranean and African olive subspecies. The nucleotide diversity was assessed and the phylogenetic relationships between alleles were depicted with haplotype networks. A Bayesian clustering method (STRUCTURE) was applied to identify the main gene pools. We found an average of 18.4 alleles per locus. Native Mediterranean and African olives only share one allele, which testifies for ancient admixture on the Red Sea hills. The presence of divergent alleles in the Mediterranean olive, as well as the identification of two main genetic clusters, suggests a complex origin with two highly differentiated gene pools from the eastern and western Mediterranean that recently admixed. In the invasive range, relatively high nucleotide diversity is observed as a consequence of the introduction of alleles from two subspecies. Our data confirm that four invasive individuals are early-generation hybrids. Finally, the utility of single-copy gene sequences in olive population genomic and phylogenetic studies is briefly discussed.
Texture zeros of neutrino mass matrix with seesaw mechanism and leptogenesis
Authors: Nguyen T. Phong
Published: March 2014

We study the seesaw realization of seven textures of the neutrino mass matrix with two zeros, which were presented by Frampton, Glashow and Marfatia. It is found that once the Dirac neutrino mass matrix is fixed, only texture A2 out of the seven textures is realized by the seesaw with three different heavy Majorana right-handed neutrino (RHN) mass matrices. As a consequence of the seesaw mechanism, the out of equilibrium decay of the lightest RHN generates a lepton number asymmetry. By the leptogenesis process, this lepton asymmetry is converted to the Baryon Asymmetry of the Universe (BAU). By a proper choice of the parameter space of the model which satisfied the low energy experimental data, the BAU is successfully explained by both flavor dependent and flavor independent leptogenesis of the model. It is also shown that the predictions of Dirac charge parity (CP) violation phase, δ CP , for some fixed parameters of high energy physics can be constrained by the current observation of baryon asymmetry.
GENERAL VALUES AND WORK VALUES OF SOCIAL WORK STUDENTS IN HONG KONG
Authors: WONG SHUI-WAI , YUEN MANTAK
Published: March 2014

This paper reports research that examines general values and work values held by university students studying social work in Hong Kong. Comparison is also made with values held by similar students studying in different majors. Results indicated that social work students rated general values such as benevolence, self-direction, universalism and tradition higher than their non-social work counterparts. They also rated work values such as altruism, creativity, supervisory relations, independence and intellectual stimulation more highly. However, the social work students held lower values associated with economic returns, thus supporting a view that students with an inclination towards social work tend to espouse self-transcendence and intrinsic work values, and are less influenced by material rewards. Among the social work respondents, gender differences were found in both general and work values. Differences were also noted between the groups with different modes of study. Implications for social work education and future research are discussed.
RESARCH ON THE HELP SEEKING EXPERIENCES OF SEXUAL VIOLENCE VICTIMS: COMMUNITY RESPONSES AND SECONDARY VICTIMIZATION
Authors: HUNG SUET-LIN
Published: March 2014

This is a research brief on a qualitative study conducted from 2009 to 2010 in Hong Kong on the experiences of sexual violence victims in dealing with the various social systems and different professionals. The findings reveal that not only did the victims suffer from being sexually assulted, they also experienced a "secondary trauma". Secondary victimization is most serious in schools, the Equal Opportunities Commission and the judical system. The police, medical and social welfare systems need to be improved as well.