bluuebunny/crossref_metadata_2025 huggingface dataset:
Behavioral impacts of disentanglement of a right whale under sedation and the energetic cost of entanglement
Authors: van der Hoop Julie , Moore Michael , Fahlman Andreas , Bocconcelli Alessandro , George Clay , Jackson Katharine , Miller Carolyn , Morin David , Pitchford Thomas , Rowles Teri , Smith Jamison , Zoodsma Barb
Published: May 2013

Protracted entanglement in fishing gear often leads to emaciation through reduced mobility and foraging ability, and energy budget depletion from the added drag of towing gear for months or years. We examined changes in kinematics of a tagged entangled North Atlantic right whale (Eg 3911), before, during, and after disentanglement on 15 January 2011. To calculate the additional drag forces and energetic demand associated with various gear configurations, we towed three sets of gear attached to a load‐cell tensiometer at multiple speeds. Tag analyses revealed significant increases in dive depth and duration; ascent, descent and fluke stroke rates; and decreases in root mean square fluke amplitude (a proxy for thrust) following disentanglement. Conservative drag coefficients while entangled in all gear configurations (mean ± SD Cd,e,go = 3.4 × 10−3 ± 0.0003, Cd,e,gb = 3.7 × 10−3 ± 0.0003, Cd,e,sl = 3.8 × 10−3 ± 0.0004) were significantly greater than in the nonentangled case (Cd,n = 3.2 × 10−3 ± 0.0003; P = 0.0156, 0.0312, 0.0078, respectively). Increases in total power input (including standard metabolism) over the nonentangled condition ranged from 1.6% to 120.9% for all gear configurations tested; locomotory power requirements increased 60.0%–164.6%. These results highlight significant alteration to swimming patterns, and the magnitude of energy depletion in a chronically entangled whale.
Socioeconomic, demographic and policy comparisons of living and deceased kidney transplantation rates across 53 countries
Authors: Bendorf Aric , Pussell Bruce A , Kelly Patrick J , Kerridge Ian H
Published: May 2013

Aim

There are more than 1.7 million sufferers of end stage kidney disease (ESKD) worldwide and for many a donated kidney provides the only chance of regaining independence from dialysis. Unfortunately, the demand for kidneys for transplantation far exceeds the available supply. It is important, therefore, that we understand the factors that may influence kidney donation rates. While certain socio‐demographic factors have been linked to kidney donation rates, few studies have examined the influence of multiple socio‐demographic factors on rates of both living and deceased kidney transplantation (KT) and none have examined their comparative effect in large numbers of culturally and socio‐politically diverse countries.

Method

In this study, we performed univariate and multivariate analyses of the influence of 15 socio‐economic factors on both the living donor (LD) and the deceased donor (DD) kidney transplantation rates (KTR) in 53 countries.

Results

Our analyses demonstrated that factors such as UN HDI (United Nations Human Development Index), religion, GDP, education, age, healthcare expenditure, presumed consent legislation and existence of a nationally managed organ donation program were associated with higher deceased KTR. In contrast, the only factors associated with living KTR were a highly significant negative association with presumed consent and variable associations with different religions.

Conclusion

We suggest that by identifying factors that affect kidney transplantation rates these can be used to develop programs for enhancing donor rates in individual countries where those rates are below the leading countries.
32S/34S isotope fractionation in plant sulphur metabolism
Authors: Tcherkez Guillaume , Tea Illa
Published: May 2013

Sulphur is a crucial microelement for plant metabolism, involved in response mechanisms to oxidative stress, C1 metabolism, electron transfer, secondary metabolism and post‐translational peptide modifications. However, relatively little is known about sulphur transport and partitioning in plants. Although key steps of sulphur assimilation have been shown using labelling with radioactive 35S in past decades, the use of a natural tracer, allowing the examination of metabolic commitments and mass balance, is desirable. Sulphur stable isotopes (32S and 34S) have been proven to be useful for the investigation of the origin of sulphur atoms in geochemistry and for the detection of the origin of sulphur atoms. Nevertheless, their use for the study of primary sulphur metabolism has been impeded by our lack of knowledge of 32S/34S isotope fractionations and convenient methods for δ34S analyses. Here, we review documented 32S/34S isotope fractionations that may apply to sulphur metabolism, and explain how they should yield disparities amongst sulphur‐containing plant compounds.
Breaking the DNA‐binding code of Ralstonia solanacearum TAL effectors provides new possibilities to generate plant resistance genes against bacterial wilt disease
Authors: de Lange Orlando , Schreiber Tom , Schandry Niklas , Radeck Jara , Braun Karl Heinz , Koszinowski Julia , Heuer Holger , Strauß Annett , Lahaye Thomas
Published: May 2013

Ralstonia solanacearum is a devastating bacterial phytopathogen with a broad host range. Ralstonia solanacearum injected effector proteins (Rips) are key to the successful invasion of host plants. We have characterized Brg11(hrpB‐regulated 11), the first identified member of a class of Rips with high sequence similarity to the transcription activator‐like (TAL) effectors of Xanthomonas spp., collectively termed RipTALs.

Fluorescence microscopy of in planta expressed RipTALs showed nuclear localization. Domain swaps between Brg11 and Xanthomonas TAL effector (TALE) AvrBs3 (avirulence protein triggering Bs3 resistance) showed the functional interchangeability of DNA‐binding and transcriptional activation domains. PCR was used to determine the sequence of brg11 homologs from strains infecting phylogenetically diverse host plants.

Brg11 localizes to the nucleus and activates promoters containing a matching effector‐binding element (EBE). Brg11 and homologs preferentially activate promoters containing EBEs with a 5′ terminal guanine, contrasting with the TALE preference for a 5′ thymine.

Brg11 and other RipTALs probably promote disease through the transcriptional activation of host genes. Brg11 and the majority of homologs identified in this study were shown to activate similar or identical target sequences, in contrast to TALEs, which generally show highly diverse target preferences. This information provides new options for the engineering of plants resistant to R. solanacearum.
Where do roots take up water? Neutron radiography of water flow into the roots of transpiring plants growing in soil
Authors: Zarebanadkouki Mohsen , Kim Yangmin X. , Carminati Andrea
Published: May 2013

Where and how fast does water flow from soil into roots? The answer to this question requires direct and in situ measurement of local flow of water into roots of transpiring plants growing in soil.

We used neutron radiography to trace the transport of deuterated water (D2O) in lupin (Lupinus albus) roots. Lupins were grown in aluminum containers (30 × 25 × 1 cm) filled with sandy soil. D2O was injected in different soil regions and its transport in soil and roots was monitored by neutron radiography. The transport of water into roots was then quantified using a convection–diffusion model of D2O transport into roots.

The results showed that water uptake was not uniform along roots. Water uptake was higher in the upper soil layers than in the lower ones. Along an individual root, the radial flux was higher in the proximal segments than in the distal segments.

In lupins, most of the water uptake occurred in lateral roots. The function of the taproot was to collect water from laterals and transport it to the shoot. This function is ensured by a low radial conductivity and a high axial conductivity. Lupin root architecture seems well designed to take up water from deep soil layers.
Electromagnetic Interference of Avalanche Transceivers with Cardiac Pacemakers and Implantable Cardioverter Defibrillators
Authors: DORENKAMP MARC , BLASCHKE FLORIAN , VOIGT KATHLEEN , FLECK ECKART , GOETZE STEPHAN , ROSER MATTIAS
Published: May 2013

Background

Avalanche transceivers are essentials tools in locating persons who were buried by an avalanche. In the past few years, avalanche transceivers have become widely available and affordable, but it is largely unknown whether they are a source of electromagnetic interference for implanted cardiac devices. We aimed to determine the potential interaction between avalanche transceivers and pacemakers or implantable cardioverter defibrillators (ICDs).

Methods

One hundred and one patients, 41 with pacemakers and 60 with ICDs, were enrolled (mean age 66 ± 15 years). Four avalanche transceivers (Pieps DSP [Pieps GmbH, Lebring, Austria], Ortovox x1, Ortovox m2, and Ortovox f1 [Otovox Sportartikel GmbH, Taufkirchen, Germany]) were evaluated in transmit as well as in receive mode. Surface electrocardiograms, intracardiac electrograms, and marker channels were continuously recorded and observed by an experienced physician. Electromagnetic interference events were categorized as direct interference with the function of the implanted device itself or as interference with the telemetric communication without compromising device function.

Results

Among all patients, there was no interference with the intrinsic function of their pacemakers or ICDs. A total of 120 episodes of telemetry interference occurred in 48% of the patients. Of those episodes, 112 of 404 (28%) were observed in transmit and eight of 404 (2%) in receive mode (P < 0.0001). The digital avalanche transceiver (Pieps DSP) was associated with significantly less telemetry interference (20/202; 10%) than the analog transceiver (Ortovox f1) (39/202; 19%) (P = 0.0108).

Conclusions

Avalanche transceivers are safe for patients with pacemakers and ICDs. Despite the observed telemetry interferences, the intrinsic function of the implanted devices was never compromised.
Clinical Efficacy and Safety of an Implantable Cardioverter‐Defibrillator Lead with a Floating Atrial Sensing Dipole
Authors: SAFAK ERDAL , SCHMITZ DIETMAR , KONORZA THOMAS , WENDE CHRISTIAN , DE ROS JOSE OLAGUE , SCHIRDEWAN ALEXANDER
Published: May 2013

Background

The concept of a single‐lead implantable cardioverter‐defibrillator (ICD), with a floating dipole, has been proven safe and functional.

Methods and Results

The studied active‐fixation, steroid‐eluting lead (Linoxsmart S DX, BIOTRONIK SE & Co KG, Berlin, Germany) is one French thinner than its predecessor and coated with lubricious SilGlide to improve lead handling. A dedicated ICD device has a self‐adaptive atrial input stage including a fourfold amplifier. The amplification, filtering, and adapted atrial input stage are located in the Lumax 540 VR‐T DX (BIOTRONIK). The Linoxsmart S DX ICD lead delivers only the signal. The lead was evaluated during implantation; at predischarge; and 1‐, 3‐, and 6‐month follow‐up examinations. The primary endpoint (efficacy) was the rate of appropriate atrial sensing tests. The secondary endpoint (safety) was freedom from lead‐related invasive reinterventions. Both safety and efficacy were expected to be significantly higher than 90%.

The study enrolled 116 patients at 25 clinical sites. Skin‐to‐skin operation time was 52.4 ± 26.2 minutes. The investigators graded lead insertion as “easy” in 87% of patients. Mean P‐wave amplitudes (preamplified) varied from 5.0 to 6.1 mV in different body positions. Both primary and secondary endpoints were met, as 93.8% (364/388; P = 0.005) of specific sensing tests indicated appropriate atrial sensing, and 94.8% (110/116; P = 0.048) of patients were free from reinterventions (lead dislodgement). Analysis of arrhythmia episodes stored in ICDs and elective 24‐hour Holter electrocardiogram tests raised no concerns about lead functionality.

Conclusion

The studied ICD lead with a floating atrial sensing dipole met the predefined safety expectation and demonstrated appropriate atrial sensing performance.
Communication of results and disclosure of incidental findings in longitudinal paediatric research
Authors: Anastasova Velizara , Mahalatchimy Aurélie , Rial‐Sebbag Emmanuelle , Antó Boqué Josep Maria , Keil Thomas , Sunyer Jordi , Bousquet Jean , Cambon‐Thomsen Anne
Published: May 2013

Background

Communicating results to research participants is an issue frequently discussed in terms of ethics. It has specific features when involving large‐scale paediatric cohorts. High‐throughput biological explorations reveal also incidental findings of medical relevance. This work analyses existing frameworks for managing such issues and proposes a policy grounded in the experience acquired in the FP7 EU project MeDALL – Mechanisms of the Development of ALLergy.

Methods

A bibliographical analysis was performed using law, ethics and academic documentation. Empirical data were acquired through informed consent forms from 9 of the 13 cohorts used in MeDALL and from replies to a general questionnaire (n = 10) on ethical issues sent to consortium members. Group discussions and expert consultations were conducted during project meetings.

Results

The notions of research results and incidental findings remain ambiguous as no agreed definition exists. The most appropriate terms are communication of results and disclosure of incidental findings. No legal norm and no specific guidance govern these issues in paediatric research at European level. Relevant policies depend on decisions in each cohort or project. The policy proposed states that these issues should be discussed during the informed consent process, with due attention to involvement of children, and a balance of interests between children, parents and society. A moral duty for researchers to communicate such information only applies if certain medical and social criteria are met.

Conclusions

As there is no consensus within European Birth cohorts how to deal with results and incidental findings, we propose a general policy.
Stratification of the Radiation Field Inside a Photobioreactor During Microalgae Growth
Authors: Heinrich Josué M. , Niizawa Ignacio , Botta Fausto A. , Trombert Alejandro R. , Irazoqui Horacio A.
Published: May 2013

Light availability is a main issue in autotrophic growth of photosynthetic microorganisms. The change of the suspended cells concentration and that of their chlorophylls content during microalgal growth alters the optical properties of the aqueous suspension. This brings about changes in the properties of the radiation field inside the reactor. In this work, we have computed the evolution in time of the local volumetric rate of absorption of photons inside a photobioreactor by means of a Monte Carlo simulation algorithm previously developed. From this study, we have computed two operational variables that are useful tools for the analysis, performance comparison, optimization and scaling up of photobioreactors: the average rate of photon absorption and the volumetric distribution function of photons absorption rates. Based on these two variables, it is possible to systematically quantify the degree of stratification of the culture medium, which is a decisive aspect that hampers the reactor efficiency regarding the energy usage for biomass production.
Mixed endometrial stromal and smooth muscle tumor: Report of a case with focal anaplasia and early postoperative lung metastasis
Authors: Shintaku Masayuki , Hashimoto Hiromi
Published: May 2013

A rare case of a mixed endometrial stromal and smooth muscle tumor arising in the uterus of a 74‐year‐old woman is reported. The patient underwent hysterectomy for an enlarging uterine mass, and a large intramural tumor, showing marked central hyaline necrosis with calcification, was found. The tumor consisted of an admixture of a low‐grade endometrial stromal sarcoma (ESS) and a fascicular proliferation of spindle cells suggesting smooth muscle differentiation, and a characteristic ‘star‐burst’ appearance was found. In the ESS region, there were a few small foci of anaplasia where large polygonal cells with atypical nuclei and abundant eosinophilic cytoplasm proliferated, and the proliferative activity was locally increased in these foci. A small metastatic nodule appeared in the lung nine months after the hysterectomy, and the resected metastatic lesion showed features of anaplastic spindle cell sarcoma which was immunoreactive for CD10 but not for smooth muscle markers. Mixed endometrial stromal and smooth muscle tumors should be regarded as malignant neoplasms with the potential for hematogenous metastasis, particularly when they contain foci of cellular anaplasia.
Visualization of phosphatidylcholine (16:0/16:0) in type II alveolar epithelial cells in the human lung using imaging mass spectrometry
Authors: Kurabe Nobuya , Hayasaka Takahiro , Igarashi Hisaki , Mori Hiroki , Sekihara Keigo , Tao Hong , Yamada Hidetaka , Kahyo Tomoaki , Onishi Ippei , Tsukui Hiroe , Kawase Akikazu , Matsuura Shun , Inoue Yusuke , Shinmura Kazuya , Funai Kazuhito , Setou Mitsutoshi , Sugimura Haruhiko
Published: May 2013

Imaging mass spectrometry (MS) is an emerging technique that can detect numerous biomolecular distributions in a non‐targeting manner. In the present study, we applied a mass imaging modality, mass microscopy, to human lung tissue and identified several molecules including surfactant constituents in a specific structure of the lung alveoli. Four peaks were identified using imaging MS, and the ion at m/z 772.5, in particular, was localized at some spots in the alveolar walls. Using an MS/MS analysis, the ion was identified as phosphatidylcholine (PC)(16:0/16:0), which is the main component of lung surfactant. In a larger magnification of the lung specimen, PC (16:0/16:0) was distributed in a mottled fashion in a section of the lung. Importantly, the distribution of PC (16:0/16:0) was identical to that of anti‐SLC34A2 antibody immunoreactivity, which is known to be a specific marker of type II alveolar epithelial cells, in the same section. Our experience suggests that imaging MS has excellent potential in human pathology research.
Photosynthesis limitations in three fern species
Authors: Gago Jorge , Coopman Rafael E. , Cabrera Hernán Marino , Hermida Carmen , Molins Arántzazu , Conesa Miquel À. , Galmés Jeroni , Ribas‐Carbó Miquel , Flexas Jaume
Published: May 2013

Maximum photosynthesis rates in ferns are generally lower than those of seed plants, but little is known about the limiting factors, which are crucial to understand the evolution of photosynthesis in land plants. To address this issue, a gas exchange/chlorophyll fluorescence analysis was performed in three fern species spanning high phylogenetic range within Polypodiopsida (Osmunda regalis, Blechnum gibbum and Nephrolepis exaltata) to determine their maximum net photosynthesis (AN), stomatal (gs) and mesophyll (gm) conductances to CO2, and the maximum velocity of carboxylation (Vc,max). The in vitro Rubisco specificity factor (SC/O) was also determined. All three species had values for SC/O similar to those typical of seed plants, but values of AN, gs, gm and Vc,max were within the lowest range of those observed in seed plants. In addition, gs was unresponsive to light and CO2, as already described in other fern species. On the contrary, gm varied with changes CO2. A quantitative photosynthesis limitation analysis suggested that early land plants (ferns) presented not only stomatal limitations—which were less adjustable to the environment—but also restricted gm and Vc,max, resulting in limited maximum photosynthesis rates.
Expression analysis of phosphoenolpyruvate carboxykinase in Porphyra haitanensis (Rhodophyta) sporophytes and gametophytes
Authors: He Linwen , Zhang Xiaojuan , Wang Guangce
Published: May 2013

Phosphoenolpyruvate carboxykinase (PEPCK) catalyzes carboxylation of phosphoenolpyruvate or decarboxylation of oxaloacetate, which plays an important role in some C4 plants and algae. The full‐length cDNA of the PEPCK gene cloned from Porphyra haitanensis T. J. Chang et B. F. Zheng (Bangiales, Rhodophyta), was denoted Phpepck. It had a nucleotide sequence of 2300 bp, including a 5′‐untranslated region (UTR) of 147 bp, a 3′‐UTR of 329 bp and an open reading frame of 1824 bp. The expression of PEPCK in P. haitanensis sporophytes and gametophytes was examined at the levels of transcription, translation and enzyme activity. Both PEPCK abundance and activity were higher in sporophytes than those in gametophytes, suggesting that a C4‐like carbon‐fixation mechanism might be functional in P. haitanensis sporophytes.
Growth, biochemical and enzymatic responses of thermal cyanobacterium Gloeocapsa sp. (Cyanophyceae) to temperature and irradiance
Authors: Gacheva Gergana V. , Gigova Liliana G. , Ivanova Natalia Y. , Pilarski Plamen S. , Lukavský Jaromír
Published: May 2013

The present study describes a strain of Gloeocapsa sp. designated as Gacheva 2007/R‐06/1, originally isolated from a geothermal flow located in Rupite, Bulgaria. To evaluate whether this cyanobacterium is locally adapted to hot environment or has the ability to tolerate lower temperatures, its growth, biochemical composition, enzyme isoforms and activity of the main antioxidant enzymes and proteases were characterized under various temperatures and two irradiance levels. The strain was able to grow over the whole temperature range (15–40°C) under two different photon fluence densities – 132 μmol photons m−2 s−1 (unilateral, low light, LL) and 2 × 132 μmol photons m−2 s−1 (bilateral, high light, HL). The best growth occurred at either 34°C and LL or at 36°C and HL, but significant growth inhibition was noted at 15°C and 40°C. Low temperature treatment (15°C) resulted in higher levels of total protein and an increased activity of manganese superoxide dismutase (MnSOD) and glutathione reductase, as compared to optimum growth temperatures. After simultaneous exposure to 15°C and HL, increases in lipid content and activity of iron superoxide dismutase and catalase (CAT) were also observed. Cultivation of cells at 40°C enhanced MnSOD, CAT and peroxidase activities, regardless of irradiance level. Increased total protein content and protease activity at 40°C was only associated with the HL treatment. Overall, these results indicate that Gloeocapsa sp. strain Gacheva 2007/R‐06/1 used different strategies to enable cells to efficiently acclimate and withstand adverse low or high temperatures. This strain obviously tolerates a wide range of temperatures below its natural habitat temperature, and does not seem to be locally adapted to its original thermal regime. It behaved as a thermotolerant rather than a thermophilic cyanobacterium, which suggests its wider distribution in nature.
The gradual transformation? The incremental dynamics of macroprudential regulation
Authors: Baker Andrew
Published: May 2013

This article focuses on the transformatory potential of macroprudential ideas following the financial crash of 2008, examining how they are being mediated by existing institutional contexts and how and why the task of building a new body of technical macroprudential knowledge is proceeding slowly. It is argued that the movement toward a form of macroprudential regulation has a distinctly incremental dynamic that means any macroprudential transformation will be a gradual process that is likely to span a decade or more. Using Peter Hall's framework of three orders of policy change across substantive and temporal dimensions, the article argues that the macroprudential ideational shift can be compared to third order change. In this sense, it was intellectually radical and took place rapidly in a period of around six months. However, intellectual radicalism does not automatically translate into a radical change in regulatory practice, because of a variety of countervailing political, institutional, and informational variables. In this respect, the task of developing first and second order macroprudential policy is proving to be a much more politically contested process. Furthermore, macroprudential policy is being developed by cautious technocrats who rely on the gradual accumulation of data and evidence to justify policy. The result is a distinctly incremental dynamic to macroprudential policy development that displays many of the features of a process that historical institutionalists refer to as “layering.”
Severe obstructive sleep apnoea is independently associated with pulmonary artery dilatation
Authors: Kawano Yoshiyuki , Tamura Akira , Watanabe Toru , Kadota Junichi
Published: May 2013

Background and objective

We hypothesised that obstructive sleep apnoea (OSA) may cause pulmonary artery dilatation through excessively negative intrathoracic pressure generated during inspiratory efforts against the upper airway collapse during obstructive apnoeas. To test this hypothesis, we examined the association between OSA severity and pulmonary artery dilatation.

Methods

A total of 173 patients who were clinically suspected of having OSA underwent chest radiography and polysomnography. We measured the right descending pulmonary artery diametre (RDPAD) on the chest radiogram and defined an abnormal increase in the RDPAD as RDPAD > 16 mm in males and RDPAD > 15 mm in females.

Results

An abnormal increase in the RDPAD was more prevalent in patients with severe OSA (46.3%) compared to those with no or mild OSA (14.5%) and those with moderate OSA (21.6%). A univariate logistic regression analysis showed that severe OSA was associated with an abnormal increase in the RDPAD (odds ratio 3.94, 95% confidence interval 1.98‐7.87). After controlling for age, gender, body mass index, smoking history and partial pressure of arterial oxygen, severe OSA still remained significantly associated with an abnormal increase in the RDPAD (odds ratio 4.06, 95% confidence interval 1.82–9.07).

Conclusions

Severe OSA is independently associated with an abnormal increase in the RDPAD, suggesting that severe OSA may cause pulmonary artery dilatation.
Focal necrotizing pneumonia is a distinct entity from lung abscess
Authors: Seo Hyewon , Cha Seung‐Ick , Shin Kyung‐Min , Lim Jaekwang , Yoo Seung‐Soo , Lee Jaehee , Lee Shin‐Yup , Kim Chang‐Ho , Park Jae‐Yong
Published: May 2013

Background and objective

‘Focal necrotizing pneumonia’ was defined as a localized type of necrotizing pneumonia characterized by a single or few cavities of low density without rim enhancement on computed tomography (CT) scan. The purpose of this study was to investigate the clinical features and course of patients with focal necrotizing pneumonia, thereby elucidating its clinical relevance.

Methods

The present study was conducted retrospectively in patients who had been interpreted as having lung abscess or necrotizing pneumonia on CT scan. Clinical and radiological characteristics were compared between the focal necrotizing pneumonia and lung abscess groups.

Results

Overall, 68 patients with focal necrotizing pneumonia (n = 35) or lung abscess (n = 33) were included in the present study. The frequency of risk factors for aspiration was significantly lower in the focal necrotizing group, compared with the lung abscess group (14.3% vs 45.5%, P = 0.005). Compared with lung abscess, focal necrotizing pneumonia was observed more commonly in non‐gravity‐dependent segments (66% vs 36%, P < 0.001). In addition, a trend towards more common isolation of aerobes as potential pathogens was observed in the focal necrotizing pneumonia group, compared with the lung abscess group (31% vs 12%, P = 0.08). However, in terms of treatment outcomes, a similar high rate of success was observed in both groups: 97%, respectively.

Conclusions

Compared to lung abscess, focal necrotizing pneumonia occurs more commonly in non‐gravity‐dependent segments with lower incidence of risk factors for aspiration. Similar to lung abscess, the rate of success for treatment of focal necrotizing pneumonia was high.
The rise and fall of XMRV
Authors: Kakisi O. K. , Robinson M. J. , Tettmar K. I. , Tedder R. S.
Published: May 2013

Due to the relatively recent emergence of the human T‐lymphotropic and the human immunodeficiency viruses, enthusiasm for the identification of novel viruses, especially retroviruses, with pathogenic potential in humans, remains high. Novel technologies are now available with the ability to search for unknown viruses, such as gene arrays and new generation sequencing of tissue and other samples. In 2006, chip technology identified a novel retrovirus in human prostate cancer (PCa) tissue samples. Due to close homology to a mouse retrovirus, the virus was named xenotropic murine leukaemia virus‐related virus (XMRV). Ever since the initial disease association with PCa, XMRV has stirred a lot of attention and concern worldwide for the medical community, public health officials and in particular global transfusion services. Public response, in this new era of electronic communication and advocacy was rapid, wide and unprecedented. In this review, we outline the course of biomedical research efforts that were put forward internationally in the process of determining the risk to the human population, the response of the blood banking community and review the current state of knowledge of xenotropic murine retroviruses. Although XMRV is no longer regarded as an infection of humans, a lesson was learnt in modern virology that holds deeper implications for biomedical research, particularly stem cell generation and transplantation practices.
Current status of potential organ donation in cases of lethal fetal anomaly
Authors: Brierley Joe
Published: May 2013

Key content

Anencephaly is the most severe form of neural tube defect with most pregnancies terminated following antenatal diagnosis and those carrying to term often stillborn.

Organ donation following anencephalic live birth has been undertaken worldwide, especially in the early years of infant transplantation. In the USA and Canada this ceased towards the end of the last century.

Although few UK transplants occurred, and the practice has ceased, national guidelines still support organ retrieval from anencephalic babies once certified dead.

With the current organ donation task‐force linked drive, obstetricians are increasingly confronted with women carrying anencephalic fetuses who decline termination, perhaps for religious reasons, who would like to consider donation.

Anencephalic donation does not occur in the UK, or indeed worldwide at present.

Learning objectives

This paper seeks to review the current UK position and possible developments, and to provide guidance for obstetricians to reply to such requests.

Ethical issues

Can a pregnant women elect for her anencephalic infant to be managed in such a manner – with organ support at delivery – that eventual donation after circulatory death can provide organs for others on the subsequent death of the baby?
Stability of relevant plasma protein activities in cryosupernatant plasma units during refrigerated storage for up to 5 days postthaw
Authors: Bhakta Varsha , Jenkins Craig , Ramirez‐Arcos Sandra , Sheffield William P.
Published: May 2013

Background

Cryosupernatant plasma (CSP) is used in Canada for plasma exchange in thrombotic thrombocytopenic purpura. The refrigerated storage time for thawed CSP is limited in many areas to not more than 24 hours postthaw. Because large volumes of CSP are needed for plasma exchange, procedural postponement can lead to product wastage. To determine if CSP storage could be extended, we measured coagulation‐related activities in CSP thawed and stored at 1 to 6°C for up to 5 days.

Study Design and Methods

Thirty‐six CSP units were thawed, refrigerated, and sampled aseptically at 0, 24, 48, and 120 hours postthaw. Clotting factor activities (Factor [F]V, FVII, FVIII, and fibrinogen) and prothrombin time were measured using an automated coagulation analyzer, and von Willebrand factor (vWF) and ADAMTS13 activities using enzyme‐linked immunosorbent assay.

Results

Fibrinogen, FVIII, and vWF activities were unchanged from thaw values after 120 hours of storage; ADAMTS13, FV, and FVII activities were significantly lower than at thaw, but mean reductions were only −2.6, −7.7, and −12%, respectively. Losses were proportionately greater in the first 24 hours of refrigerated storage.

Conclusions

Extending the refrigerated storage of CSP from 1 to 5 days had little impact on product quality. The retention of more than 97% of initial mean ADAMTS13 activity after 5 days of refrigerated storage suggests that the shelf life of thawed refrigerated CSP could be extended without meaningful losses of its likely most important ingredients. CSP postthaw storage could be aligned to that of refrigerated thawed frozen plasma, currently available for transfusion in some jurisdictions for up to 5 days postthaw.
Seven new champion linear codes
Authors: Brown Gavin , Kasprzyk Alexander M.
Published: May 2013

We exhibit seven linear codes exceeding the current best known minimum distance $d$ for their dimension $k$ and block length $n$. Each code is defined over ${ \mathbb{F} }_{8} $, and their invariants $[n, k, d] $ are given by $[49, 13, 27] $, $[49, 14, 26] $, $[49, 16, 24] $, $[49, 17, 23] $, $[49, 19, 21] $, $[49, 25, 16] $ and $[49, 26, 15] $. Our method includes an exhaustive search of all monomial evaluation codes generated by points in the $[0, 5] \times [0, 5] $ lattice square.
Translational physiology: from molecules to public health
Authors: Seals Douglas R.
Published: May 2013

Abstract  The term ‘translational research’ was coined 20 years ago and has become a guiding influence in biomedical research. It refers to a process by which the findings of basic research are extended to the clinical research setting (bench to bedside) and then to clinical practice and eventually health policy (bedside to community). It is a dynamic, multidisciplinary research approach. The concept of translational physiology applies the translational research model to the physiological sciences. It differs from the traditional areas of integrative and clinical physiology by its broad investigative scope of basic research to community health. Translational physiology offers exciting opportunities, but presently is under‐developed and ‐utilized. A key challenge will be to expand physiological research by extending investigations to communities of patients and healthy (or at risk) individuals. This will allow bidirectional physiological investigation throughout the translational continuum: basic research observations can be studied up to the population level, and mechanisms can be assessed by ‘reverse translation’ in clinical research settings and preclinical models based on initial observations made in populations. Examples of translational physiology questions, experimental approaches, roadblocks and strategies for promotion are discussed. Translational physiology provides a novel framework for physiology programs and an investigational platform for physiologists to study function from molecular events to public health. It holds promise for enhancing the completeness and societal impact of our work, while further solidifying the critical role of physiology in the biomedical research enterprise.
Effects of the insertional and appositional forces of the canine diaphragm on the lower ribs
Authors: Wilson Theodore A. , De Troyer André
Published: May 2013

Key points

Although the diaphragm causes a fall in pleural pressure, it expands the lower portion of the ribcage when it contracts.

This action is conventionally considered to be the result of two mechanisms, namely, the force applied by the muscle fibres on the ribs into which they insert (insertional force) and the transmission of abdominal pressure through the zone of apposition (appositional force).

In this study in anaesthetized dogs, we assessed the magnitude of the force exerted by the diaphragm on the lower ribs and the relative contributions of the insertional and appositional components.

The results show that, per unit pressure, the inspiratory effect of the diaphragmatic force on the lower ribs is equal to the expiratory effect of pleural pressure and that the insertional force contributes 60% of that inspiratory effect.

Abstract  The diaphragm has an inspiratory action on the lower ribs, and current conventional wisdom maintains that this action is the result of two mechanisms, namely, the force applied by the muscle fibres on the ribs into which they insert (insertional force) and the transmission of abdominal pressure through the zone of apposition (appositional force). The magnitude of the diaphragmatic force and the relative contributions of the insertional and appositional components, however, are unknown. To assess these forces, the inspiratory intercostal muscles in all interspaces were severed in anaesthetized dogs, so that the diaphragm was the only muscle active during inspiration, and the displacements of the lower ribs along the craniocaudal and laterolateral axes were measured during quiet breathing, during occluded breaths and during passive lung inflation. From these data, the isolated effects of pleural pressure and transdiaphragmatic pressure on rib displacement were determined. Then external forces were applied to the ribs in the cranial and the lateral direction to simulate, respectively, the effects of the insertional and appositional forces, and the rib trajectories for these external forces were used as the basis for a vector analysis to obtain the relative magnitudes of the insertional and appositional contributions to the rib displacement driven by transdiaphragmatic pressure. The results show that, per unit pressure, the inspiratory effect of the diaphragmatic force on the lower ribs is equal to the expiratory effect of pleural pressure, and that the insertional force contributes 60% of that inspiratory effect.
Doublet discharge stimulation increases sarcoplasmic reticulum Ca2+ release and improves performance during fatiguing contractions in mouse muscle fibres
Authors: Cheng Arthur J. , Place Nicolas , Bruton Joseph D. , Holmberg Hans‐Christer , Westerblad Håkan
Published: May 2013

Key points

Motor neurons are frequently activated to give two action potentials at 200–300 Hz (doublets) at the onset of voluntary contractions. Doublets increase force and rate of force development.

During fatigue, decreased sarcoplasmic reticulum Ca2+ release and decreased myofibrillar Ca2+ sensitivity both contribute to the fatigue‐induced force loss. We studied whether electrically evoked doublets at contraction onset can counteract such fatigue‐induced changes. Experiments were performed using intact fast‐twitch and slow‐twitch single muscle fibres of mice.

In the unfatigued state, doublets induce increased sarcoplasmic reticulum Ca2+ release at the onset of contractions, which increases peak force and force–time integral. During fatigue induced by 150 repeated contractions, doublets markedly improve isometric force production during the first 25 contractions. At the end of fatigue, addition of doublets at contraction onset can temporarily increase force production.

Doublets are beneficial in that they improve contractile performance when added at any stage of strenuous activity, although the effect is largest in early fatigue stages.

Abstract  Double discharges (doublets) of motor neurones at the onset of contractions increase both force and rate of force development during voluntary submaximal contractions. The purpose of this study was to examine the role of doublet discharges on force and myoplasmic free [Ca2+] ([Ca2+]i) during repeated fatiguing contractions, using a stimulation protocol mimicking the in vivo activation pattern during running. Individual intact fibres from the flexor digitorum brevis muscle of mice were stimulated at 33°C to undergo 150 constant–frequency (five pulses at 70 Hz) or doublet (an initial, extra pulse at 200 Hz) contractions at 300 ms intervals. In the unfatigued state, doublet stimulation resulted in a transient (∼10 ms) approximate doubling of [Ca2+]i, which was accompanied by a greater force–time integral (∼70%) and peak force (∼40%) compared to constant frequency contractions. Moreover, doublets markedly increased force–time integral and peak force during the first 25 contractions of the fatiguing stimulation. In later stages of fatigue, addition of doublets increased force production but the increase in force production corresponded to only a minor portion of the fatigue‐induced reduction in force. In conclusion, double discharges at the onset of contractions effectively increase force production, especially in early stages of fatigue. This beneficial effect occurs without additional force loss in later stages of fatigue, indicating that the additional energy cost induced by doublet discharges to skeletal muscle is limited.
Optimizing Temper Bead Welding by Computational Weld Mechanics and Design of Experiment Matrix
Authors: Asadi Mahyar , Bayley Christopher , Goldak John
Published: May 2013

Temper bead welding is usually done by experiment, i.e., trial and error. This paper describes a computational weld mechanics model to compute the transient temperature and transient microstructure evolution in temper bead welds. The computed hardness from this model, is compared to measured hardness for validation. Furthermore, the effects of power per unit length, welding current, and welding speed on final hardness, are studied by designing and implementing three design-of-experiment matrices.
Atomic layer deposition of zinc oxide: Understanding the reactions of ozone with diethylzinc
Authors: Warner Ellis J. , Cramer Christopher J. , Gladfelter Wayne L.
Published: May 2013

To understand the reactions involved in the atomic layer deposition (ALD) of zinc oxide films using ozone as the oxygen source, two model systems were examined at the M06-L and M06 levels of density functional theory. The first model involved a two-coordinate zinc complex, HO-Zn-Et, and the second, [(HO)7Zn4(Et)], a cluster having a cubane-like geometry in which each of the zinc ions is four-coordinate. In both cases, the ozone reaction requires two distinct steps to generate a new hydroxyl ligand, which is required for the second phase of the ALD process (reaction with Et2Zn). In step 1, an exothermic insertion of O3 into the Zn-C bond produces an ethyltrioxide (EtOOO–) ligand as an intermediate. Subsequently, a mildly exothermic elimination of singlet oxygen produces an ethoxide complex. In step 2, a second equivalent of ozone abstracts a methylene hydrogen from the ethoxide ligand, resulting in the elimination of acetaldehyde and the formation of a hydrotrioxide (HOOO−) ligand that ultimately eliminates O2 and leaves a hydroxide group bound to the zinc. To simulate one complete ALD cycle, Et2Zn was subsequently reacted with the hydroxyl terminated products from step 1, i.e., Zn(OH)2 or Zn4(OH)8. In the cubane-like model, the geometric availability of additional OH groups opens a 1,4 ethane elimination pathway with an activation energy 7.1 kcal/mol lower than that for 1,2-elimination. A series of experimental ZnO depositions using Et2Zn and O3 were run in a reactor that was modified to allow collection of condensable organic products of the reaction. Acetaldehyde was detected, and quantitative nuclear magnetic resonance established a linear correlation between the amount of acetaldehyde and the number of ALD cycles, consistent with the mechanism inferred on the basis of the computational models.
Epigenetic Regulation by Vitamin C
Authors: Ferrarelli Leslie K.
Published: May 2013

Vitamin C is a cofactor for Tet-mediated DNA demethylation.
Maculatin 1.1 Disrupts Staphylococcus aureus Lipid Membranes via a Pore Mechanism
Authors: Sani M.-A. , Whitwell T. C. , Gehman J. D. , Robins-Browne R. M. , Pantarat N. , Attard T. J. , Reynolds E. C. , O'Brien-Simpson N. M. , Separovic F.
Published: May 2013

Maculatin 1.1 (Mac1) showed potent activity against
Staphylococcus aureus
with an MIC of 7 μM. The mode of action of Mac1 was investigated by combining assays with
S. aureus
cells and lipid vesicles mimicking their membrane composition. A change in Mac1 conformation was monitored by circular dichroism from random coil to ca. 70% α-helix structure in contact with vesicles. Electron micrographs of
S. aureus
incubated with Mac1 showed rough and rippled cell surfaces. An uptake of 65% of small (FD, 4 kDa [FD-4]) and 35% of large (RD, 40 kDa [RD-40]) fluorescent dextrans by
S. aureus
was observed by flow cytometry and indicate that Mac1 formed a pore of finite size. In model membranes with both dyes encapsulated together, the full release of FD-4 occurred, but only 40% of RD-40 was reached, supporting the flow cytometry results, and indicating a pore size between 1.4 and 4.5 nm. Finally, solid-state nuclear magnetic resonance showed formation of an isotropic phase signifying highly mobile lipids such as encountered in a toroidal pore structure. Overall, Mac1 is a promising antimicrobial peptide with the potent capacity to form pores in
S. aureus
membranes.
Induction of Plasmid-Carried
qnrS1
in Escherichia coli by Naturally Occurring Quinolones and Quorum-Sensing Signal Molecules
Authors: Kwak Yee Gyung , Jacoby George A. , Hooper David C.
Published: May 2013

Naturally occurring quinolone and quinolone-like compounds, such as quinine, 2-hydroxyquinoline, 4-hydroxyquinoline, and 2-heptyl-3-hydroxy-4(1H)-quinolone, increased expression of
qnrS1
in
Escherichia coli
2.3- to 11.2-fold, similar to the synthetic quinolone ciprofloxacin. In contrast, chromosomal
qnrVS1
of
Vibrio splendidus
was not induced by these compounds. Molecules associated with quorum sensing, such as
N
-3-hydroxybutyryl-homoserine lactone (HSL),
N
-hexanoyl-HSL, and
N
-3-(oxododecanoyl)-HSL, did not show an induction effect on either
qnrS1
or
qnrVS1
at the tested concentrations.
Coadministration of Atazanavir-Ritonavir and Zinc Sulfate: Impact on Hyperbilirubinemia and Pharmacokinetics
Authors: Moyle Graeme , Else Laura , Jackson Akil , Back David , Yapa Manisha H. , Seymour Natalia , Ringner-Nackter Lisa , Karolia Zeenat , Gazzard Brian , Boffito Marta
Published: May 2013

Atazanavir (ATV) causes an elevation of unconjugated hyperbilirubinemia (HBR) as a result of UDP glucuronyltransferase (UGT) 1A1 inhibition. Zinc sulfate (ZnSO
4
) reduces unconjugated hyperbilirubinemia in individuals with Gilbert's syndrome. We assessed the changes in total, conjugated, and unconjugated bilirubin and the effect on ATV pharmacokinetics (PK) after single and 14-day dosing of ZnSO
4
. HIV patients, stable on ATV/ritonavir (ATV/r)-containing regimens with a total bilirubin level of >25mmol/liter received 125 mg daily of ZnSO
4
as Solvazinc tablets for 14 days. ATV/r and bilirubin concentrations were measured pre-ATV/r dose and 2, 4, 6, 8, and 24 h post-ATV/r dose; before ZnSO
4
initiation (phase 1), after a single dose (phase 2) and after 14 days (phase 3). Changes in bilirubin and ATV/r concentrations in the absence or presence of ZnSO
4
were evaluated by geometric mean ratios (GMRs) and 90% confidence intervals (CIs; we used phase 1 as a reference). Sixteen male patients completed the study maintaining virologic suppression; ZnSO
4
was well tolerated. Statistically significant declines in total bilirubin
C
max
and AUC
0–24
of 16 and 17% were seen in phase2 and 20% in phase 3. Although there were no significant changes in conjugated bilirubin, unconjugated bilirubin
C
max
and AUC
0–24
of were lower (17 and 19%, phase 2; 20 and 23% during phase 3). The ATV GMRs (90% CI) for
C
trough
,
C
max
, and AUC
0–24
were 0.74 (0.62 to 0.89), 0.82 (0.70 to 0.97), and 0.78 (0.70 to 0.88). Intake of ZnSO
4
decreases total and unconjugated bilirubin and causes modest declines in ATV exposure. ZnSO
4
supplementation may be useful in management of ATV-related HBR in selected patients.