bluuebunny/crossref_metadata_2025 huggingface dataset:
State of the art: Stem cells in equine regenerative medicine
Authors: Lopez M. J. , Jarazo J.
Published: June 2014

According to Greek mythology, Prometheus' liver grew back nightly after it was removed each day by an eagle as punishment for giving mankind fire. Hence, contrary to popular belief, the concept of tissue and organ regeneration is not new. In the early 20th century, cell culture and ex vivo organ preservation studies by Alexis Carrel, some with famed aviator Charles Lindbergh, established a foundation for much of modern regenerative medicine. While early beliefs and discoveries foreshadowed significant accomplishments in regenerative medicine, advances in knowledge within numerous scientific disciplines, as well as nano‐ and micromolecular level imaging and detection technologies, have contributed to explosive advances over the last 20 years. Virtually limitless preparations, combinations and applications of the 3 major components of regenerative medicine, namely cells, biomaterials and bioactive molecules, have created a new paradigm of future therapeutic options for most species. It is increasingly clear, however, that despite significant parallels among and within species, there is no ‘one‐size‐fits‐all’ regenerative therapy. Likewise, a panacea has yet to be discovered that completely reverses the consequences of time, trauma and disease. Nonetheless, there is no question that the promise and potential of regenerative medicine have forever altered medical practices. The horse is a relative newcomer to regenerative medicine applications, yet there is already a large body of work to incorporate novel regenerative therapies into standard care. This review focuses on the current state and potential future of stem cells in equine regenerative medicine.
Toll‐like receptor 2 mediates a cutaneous reaction induced by repetitive ultraviolet B irradiation in C57/BL6 mice in vivo
Authors: Park Hyun Sun , Jin Seon Pil , Lee Youngae , Oh In Gyung , Lee Serah , Kim Jung Ho , Cho Kwang Hyun , Chung Jin Ho
Published: June 2014

Toll‐like receptors (TLRs) mediate not only innate immunity against infection and but also sterile inflammation triggered by endogenous molecules. We conducted a comparative study of the different inflammatory responses induced by repetitive ultraviolet (UV) B irradiation in wild‐type (WT) and TLR2 knockout (KO) mice, to provide in vivo evidence of the role of TLRs in mediating UVB‐induced responses. UVB‐induced inflammatory responses were less severe in TLR2 KO mice than in WT mice after 6 weeks of repeated UVB irradiation. UVB‐treated TLR2 KO mice displayed less prominent erythema and scaling, and histopathology showed significantly thinner skin and less inflammatory cell infiltration than that in WT mice. UVB‐induced expression of heat‐shock protein 70 (an endogenous ligand of TLR2) was lower in TLR2 KO mice. Quantitative RT‐PCR revealed significantly lower gene expression levels of UVB‐induced interleukin (IL)‐1β, IL‐6 and matrix metalloproteinase (MMP)‐13 in TLR2 KO mice. TLR2 KO mice also showed significantly lower protein level expression of UVB‐induced IL‐1β in ELISA and MMP‐13 in Western blots. Our study demonstrated that TLR2 was associated with inflammatory responses to repetitive UVB irradiation in C57/BL6 mice. Moreover, it suggests that the role of TLR2 in the cutaneous response of UV irradiation and in developing new agents for modulating the effects of UV irradiation should be considered.
Magnesium‐dependent folding of a picornavirus IRES element modulates RNA conformation and eIF4G interaction
Authors: Lozano Gloria , Fernandez Noemi , Martinez‐Salas Encarnacion
Published: June 2014

Internal ribosome entry site (IRES) elements are high‐order RNA structures that promote internal initiation of translation to allow protein synthesis under situations that compromise the general cap‐dependent translation mechanism. Picornavirus IRES elements are highly efficient elements with a modular RNA structure organization. Here we investigated the effect of Mg2+ concentration on the local flexibility and solvent accessibility of the foot‐and‐mouth disease virus (FMDV) IRES element measured on the basis of selective 2′‐hydroxyl acylation analyzed by primer extension (SHAPE) reactivity and hydroxyl radical cleavage. We have found that Mg2+ concentration affects the organization of discrete IRES regions, mainly the apical region of domain 3, the 10 nt loop of domain 4, and the pyrimidine tract of domain 5. In support of the effect of RNA structure on IRES activity, substitution or deletion mutants of the 10 nt loop of domain 4 impair internal initiation. In addition, divalent cations affect the binding of eIF4G, a eukaryotic initiation factor that is essential for IRES‐dependent translation that interacts with domain 4. Binding of eIF4G is favored by the local RNA flexibility adopted at low Mg2+ concentration, while eIF4B interacts with the IRES independently of the compactness of the RNA structure. Our study shows that the IRES element adopts a near‐native structure in the absence of proteins, shedding light on the influence of Mg2+ ions on the local flexibility and binding of eIF4G in a model IRES element.
A review of equivalent pre‐crack sizes in aluminium alloy 7050‐T7451
Authors: Molent L.
Published: June 2014

This paper reviews some analyses of quantitative fractography measurements of the fatigue fracture surfaces of 7050 aluminium alloy specimens along with relevant fatigue crack information including crack initiating discontinuity size and type. These data were used to assess whether surface finish or applied stress level has any effect on the estimated effective crack initiating discontinuity size, namely the equivalent pre‐crack size (EPS). The statistical distributions for the EPSs of the following initiating discontinuity types were examined: chemically etched pits, glass bead peening damage, mechanical damage, inclusions and porosity. The EPSs at various percentile levels for these types were determined on the basis of the samples considered. Finally, the correlation between measured initiating discontinuity depth and EPS was investigated, and good correlation was found in the case of mechanical damage. The purpose of conducting these analyses was to gain a better understanding of the parameters governing the fatigue crack‐like effect of discontinuities to facilitate the better prediction of fatigue lives.
Fatigue crack tip damaging micromechanisms in pearlitic ductile cast irons
Authors: Iacoviello F. , Di Cocco V. , Rossi A. , Cavallini M.
Published: June 2014

In the last years, damaging micromechanisms in ductile cast irons (DCIs) were widely investigated: DCI microstructure (ranging from ferritic–pearlitic DCIs to austempered ones), graphite elements morphology (shape, dimension and distributions) and loading conditions were the main investigated parameters. Focusing on the role played by the graphite nodules, they were considered merely as voids embedded in a metal matrix. Recent analysis underlined that the nodules role in the DCIs damage evolution is more complicated and is influenced by the matrix microstructure. In this work, the crack tip damaging micromechanisms in a pearlitic DCI is investigated considering both fatigue loading conditions and the effects of overloads, focusing the interaction between the crack and the investigated DCI microstructure (pearlitic matrix and graphite nodules). On the basis of experimental results, the applicability of ASTM E399 standard on the characterization of fatigue crack propagation resistance in pearlitic DCIs is critically re‐analyzed.
Predicting potential responses to future climate in an alpine ungulate: interspecific interactions exceed climate effects
Authors: Mason Tom H.E. , Stephens Philip A. , Apollonio Marco , Willis Stephen G.
Published: June 2014

The altitudinal shifts of many montane populations are lagging behind climate change. Understanding habitual, daily behavioural rhythms, and their climatic and environmental influences, could shed light on the constraints on long‐term upslope range‐shifts. In addition, behavioural rhythms can be affected by interspecific interactions, which can ameliorate or exacerbate climate‐driven effects on ecology. Here, we investigate the relative influences of ambient temperature and an interaction with domestic sheep (Ovis aries) on the altitude use and activity budgets of a mountain ungulate, the Alpine chamois (Rupicapra rupicapra). Chamois moved upslope when it was hotter but this effect was modest compared to that of the presence of sheep, to which they reacted by moving 89–103 m upslope, into an entirely novel altitudinal range. Across the European Alps, a range‐shift of this magnitude corresponds to a 46% decrease in the availability of suitable foraging habitat. This highlights the importance of understanding how factors such as competition and disturbance shape a given species’ realised niche when predicting potential future responses to change. Furthermore, it exposes the potential for manipulations of species interactions to ameliorate the impacts of climate change, in this case by the careful management of livestock. Such manipulations could be particularly appropriate for species where competition or disturbance already strongly restricts their available niche. Our results also reveal the potential role of behavioural flexibility in responses to climate change. Chamois reduced their activity when it was warmer, which could explain their modest altitudinal migrations. Considering this behavioural flexibility, our model predicts a small 15–30 m upslope shift by 2100 in response to climate change, less than 4% of the altitudinal shift that would be predicted using a traditional species distribution model‐type approach (SDM), which assumes that species’ behaviour remains unchanged as climate changes. Behavioural modifications could strongly affect how species respond to a changing climate.
Identification and characterization of retinoic acid‐responsive genes in mouse kidney development
Authors: Takayama Mami , Miyatake Koichi , Nishida Eisuke
Published: June 2014

Retinoic acid (RA) signaling regulates a variety of developmental processes through controlling the expression of numerous genes. Here, we have identified and characterized RA‐responsive genes in mouse kidney development. Analysis of isolated embryonic kidneys cultured in the presence and absence of RA identified 33 candidates of RA‐responsive genes. Most of these candidate genes were down‐regulated by treatment with the RA receptor antagonist. Many of them have potential binding sites for Elf5, one of the RA‐responsive genes, in their promoter region. Whole‐mount in situ hybridization showed that specific expression of Elf5 in the ureteric trunk depends on RA. RA‐dependent expression in the ureteric trunk was also showed for the sodium channel subunit Scnn1b, which has been shown to be the marker gene of the collecting duct. In contrast, the expression of Ecm1, Tnfsf13b and IL‐33 was detected in the stromal mesenchymal cells. Both Tnfsf13b and IL‐33 were previously shown to cause nuclear factor κB (NF‐κB) activation. We have showed that the inhibition of NF‐κB signaling with specific inhibitors suppresses branching morphogenesis of the ureteric bud. Our study thus identifies and characterizes RA‐dependent up‐regulated genes in kidney development, and suggests an involvement of NF‐κB signaling in the branching morphogenesis.
Joint Hypermobility and Headache: The Glue That Binds the Two Together – Part 2
Authors: Martin Vincent T. , Neilson Derek
Published: June 2014

Background

Past studies have reported that connective tissue disorders (CTDs) are more common in patients with specific types of headache disorders.

Objectives

The objectives of this study are (1) to review and critique the clinical studies reporting an association between joint hypermobility, CTDs and headache and (2) to postulate mechanisms though which CTDs might predispose to headache disorders.

Methods

PubMed was searched for relevant articles with search terms that included joint hypermobility, Ehlers–Danlos syndrome, Marfan syndrome, and specific headache disorders. A narrative review was performed of these articles as well as those identified from the bibliography of these articles.

Results

Case reports and case control studies confirm an association between CTDs and migraine, coat‐hanger headaches, carotid arterial dissections, intracranial hypotension, Arnold Chiari malformations‐type 1, cervical spine disorders, and temporomandibular joint disorders.

Conclusions

Observational cross‐sectional studies suggest that the prevalence of CTDs is increased in patients with specific types of headache disorders. It is unknown if the CTDs directly cause these headaches disorders or are associated with them through other mechanisms.
Electrical Characterization of Pd‐Doped CMAS‐TiO2 Glass‐Ceramics
Authors: Davis Mark J. , Vullo Paula , Reich Maria‐Louisa
Published: June 2014

Electrical characterization was performed on Pd‐bearing and Pd‐free, electrically conductive glass‐ceramics in the CMAS‐TiO2 system. AC impedance plots clearly revealed both grain‐core and grain‐boundary semicircles. Grain boundaries had a lower magnitude of conductivity but a similar activation energy to grain‐core conduction except when Pd was present, for which much lower activation energies were indicated. The lack of any frequency (f) dependence of conductivity for f < 100 Hz, while using noble metal electrodes, suggests the conduction was dominantly electronic in origin in these glass‐ceramics. Time‐dependent polarization measurements showed no change in electrical current over several days, also consistent with this conclusion. Overall, the temperature dependence of the conductivity was relatively low over a very large temperature range, but quite complex. The appearance of a sharp minimum in conduction seen near 600°C suggests some type of transition occurred with our glass‐ceramics, possibly related to semiconductor‐to‐metal transitions seen with some transition‐metal crystals. The available data suggest that Pd did have some effect on grain‐boundary conduction, but that a percolating Pd network was not formed.
Interleukin‐2‐mediated inhibition of dendritic cell development correlates with decreased CD135 expression and increased monocyte/macrophage precursors
Authors: Guerrero Alan D. , Dong Matthew B. , Zhao Yongge , Lau‐Kilby Annie , Tarbell Kristin V.
Published: June 2014

We have previously shown that interleukin‐2 (IL‐2) inhibits dendritic cell (DC) development from mouse bone marrow (BM) precursors stimulated with the ligand for FMS‐like tyrosine kinase 3 receptor (Flt3L), and have provided evidence that this inhibition occurs at the monocyte DC precursor stage of DC development. Here, we explored the mechanism of IL‐2‐mediated inhibition of DC development. First, we showed that these in vitro cultures accurately model DCs that develop in vivo by comparing gene and protein expression of the three main Flt3L‐induced DC subsets from the BM, CD11b+ and CD24+ conventional DCs (cDCs) and plasmacytoid DCs (pDCs) with their respective ex vivo spleen DC subsets (CD11b+, CD8+ and pDCs). Next, gene expression changes were quantified in Flt3L DC subsets that developed in the presence of IL‐2. These changes included increased expression of Bcl2l11, which encodes the apoptosis‐inducing protein Bim, and decreased expression of Flt3 (CD135), the receptor that initiates DC development. Interleukin‐2 also significantly reduced Flt3 protein expression on all three Flt3L DC subsets, and attenuated Flt3L‐induced STAT3 phosphorylation in DCs. Based on these data, we hypothesized that decreased Flt3 signalling may divert BM precursors down monocyte and macrophage lineages. Indeed, addition of IL‐2 led to increases in Flt3− cells, including cKit+ Ly6C+ CD11b− populations consistent with the recently identified committed monocyte/macrophage progenitor. Therefore, IL‐2 can inhibit DC development via decreased signalling through Flt3 and increased monocyte/macrophage development.
Prenatal dexamethasone exposure in rats results in long‐term epigenetic histone modifications and tumour necrosis factor‐α production decrease
Authors: Yu Hong‐Ren , Kuo Ho‐Chang , Chen Chih‐Cheng , Sheen Jiunn‐Ming , Tiao Mao‐Meng , Chen Yu‐Chieh , Chang Kow‐Aung , Tain You‐Lin , Huang Li‐Tung
Published: June 2014

Glucocorticoid (GC) is often given when preterm delivery is expected. This treatment is successful in stimulating the development of the fetal lung. However, reports and related research regarding the prolonged effects of prenatal GC on the development of immunity are very limited. Some data, derived from infants whose mothers were given immunosuppressants during pregnancy for the treatment of autoimmune disorders, suggest that prenatal exposure to GC may have only a limited effect on the development of the immune system. What is unknown is whether the immune modulation effects of prenatal GC might appear at a later childhood stage and beyond. Here we evaluated the immune programming influenced by prenatal GC. Pregnant Sprague‐Dawley rats received dexamethasone (DEX; 0·1 mg/kg/day) or saline at gestational days 14–20. Male offspring were killed at day 7 or day 120 after birth. Spleens were collected for immune study. Of the inflammation mediators, matrix metalloproteinase‐9, tumour necrosis factor‐α (TNF‐α) and granulocyte–macrophage colony‐stimulating factor mRNAs decreased in the prenatal DEX group at an early stage after birth. Upon concanavalin A stimulation, prenatal DEX treatment reduced TNF‐α production, but not interferon‐γ production, by splenocytes at day 120 after birth compared with the vehicle group. Decreased levels of active chromatin signs (acetylation of histone H3 lysines, H3K4me1/3, and H3K36me3) in TNF‐α promoter were compatible with the expressions of TNF‐α. Our results suggest that prenatal DEX has a profound and lasting impact on the developing immune system even to the adult stage. Epigenetic histone modifications regulate TNF‐α expression following prenatal DEX in rats.
A Conversation with James O. Ramsay
Authors: Genest Christian , Nešlehová Johanna G.
Published: June 2014

Jim Ramsay was born on September 5, 1942, in Prince George, British Columbia. He pursued undergraduate studies at the University of Alberta, where he completed a BEd in 1964 with a major in English and a minor in mathematics. He then specialized in statistics and psychometry, earning a PhD in psychology from Princeton University in 1966. After holding a temporary lectureship in the Department of Psychology at University College London for one year, he joined the Department of Psychology at McGill University, where he rose through the academic ranks. He was chair of his department from 1986 to 1989 and spent sabbatical leaves in Cambridge, Grenoble, and Toulouse. He was named professor emeritus upon his retirement in 2007. Jim is the author of four influential books and over 100 peer‐reviewed articles in statistical and psychometric journals. He developed much of the statistical theory behind multidimensional scaling and is widely recognized as the founder of functional data analysis. Three of his papers were read to the Royal Statistical Society, and another wonThe Canadian Journal of Statistics2000 Best Paper Award. The Statistical Society of Canada (SSC) awarded him a Gold Medal for research in 1998 and an honorary membership in 2012. Jim was president of the Psychometric Society in 1981–82 and president of the SSC in 2002–03. The following conversation took place at Jim's home in Ottawa, Ontario, on March 14 and April 4, 2012.
Impact of preceding respiratory viral infections on the clinical severity of patients with pneumococcal pneumonia
Authors: Yoon Young Kyung , Yang Kyung Sook , Sohn Jang Wook , Lee Chang Kyu , Kim Min Ja
Published: June 2014

Background

This study aimed to investigate the impact of preceding respiratory viral infections (RVI) on the clinical severity of pneumococcal pneumonia patients.

Methods

A retrospective observational study was conducted at a university hospital from January 2009 to March 2013. Study subjects included adults (aged ≥18 years) with pneumococcal pneumonia who had undergone laboratory tests for RVI. Multivariate logistic regression analysis was performed to identify risk factors associated with severe pneumococcal pneumonia, defined as severity with the Pneumonia Severity Index (PSI) score ≥91.

Results

In total, 191 patients with pneumococcal pneumonia were included for analysis and stratified into 2 groups: the severe group with a PSI score ≥91 (n = 99) and the non‐severe group with a PSI score <91 (n = 92). Preceding RVIs were detected in 48 patients, including influenza A virus (n = 20), influenza B virus (n = 4), parainfluenza viruses (n = 5), metapneumovirus (n = 4), rhinovirus (n = 4), respiratory syncytial viruses (n = 6), coronaviruses (n = 2), and mixed viral infections (n = 3). In the multivariate logistic regression analysis, preceding RVIs (odds ratio [OR], 2·49; 95% confidence interval [CI], 1·10–5·60), male sex (OR, 2·58; 95% CI, 1·24–5·38), old age (OR, 2·92; 95% CI, 1·37–6·24), hypoalbuminemia (OR, 3·26; 95% CI, 1·56–6·84)], and azotemia (OR, 2·24; 95% CI, 1·08–4·67) were significantly associated with severe pneumococcal pneumonia.

Conclusion

This study suggests that preceding RVIs might be one of the risk factors affecting the clinical severity of pneumococcal pneumonia.
A study of decision process in MCDM problems with large number of criteria
Authors: Liu Jian , Liu Peng , Liu Si‐Feng , Zhou Xian‐Zhong , Zhang Tao
Published: June 2014

In this paper, an effective decision process method is proposed to address the challenge in a multiple criteria decision‐making (MCDM) problem because of large number of criteria. This method is based on the criteria reduction, tolerance relation, and prospect theory (PT). By building a discernibility matrix for tolerance relation (DMTR) in an MCDM problem with numerical values or interval numbers, this method first allows us to recognize a set of critical criteria from a large criteria pool, and ignore the other criteria. Next, it establishes the criteria weights through the DMTR as they are usually not indicated in the data. Then, the method ranks all the choices and selects the most desirable choice according to the weighted majority advantage value (WMAV). Here two risk‐preference assumptions are proposed based on the PT and tolerance degree to select the WMAVs of different interval numbers with the same expectation. Using different risk‐preference assumptions, we separately build WMAVs for different types of DMs. Finally, we presented two voting examples to demonstrate the applicability and effectiveness of the proposed method.
A simulated annealing with multiple‐search paths and parallel computation for a comprehensive flowshop scheduling problem
Authors: Defersha Fantahun M.
Published: June 2014

Recent studies have demonstrated that the performance of a simulated annealing algorithm can be improved by following multiple‐search paths and parallel computation. In this paper, we use these strategies to solve a comprehensive mathematical model for a flexible flowshop lot streaming problem. In the flexible flowshop environment, a number of jobs will be processed in several consecutive production stages, and each stage may involve a certain number of parallel machines that may not be identical. Each job has to be split into several unequal sublots by following the concept of lot streaming. The sublots are to be processed in the order of the stages, and sublots of certain products may skip some stages. This complex problem also incorporates sequence‐dependent setup times, the anticipatory or nonanticipatory nature of setups, release dates for machines, and machine eligibility. Numerical examples are presented to demonstrate the effectiveness of lot streaming in hybrid flowshops, the performance of the proposed simulated annealing algorithm, and the improvements achieved using parallel computation.
Contract efficiency for a decentralized supply chain in the presence of quality improvement
Authors: Yan Xinghao
Published: June 2014

In this paper, we study a joint pricing and product quality decision problem in a decentralized supply chain consisting of one manufacturer and one retailer. Although the manufacturer decides the product quality with an associated cost, the retailer decides the retail price. We aim to study and compare different contract formats for this decentralized supply chain. There is a trade‐off in the choice of contracts: simpler format contract (with a few parameters) is less complicated, but the contract efficiency is low. We start with the simplest one‐parameter contract: a wholesale price contract that serves as the benchmark. We then study how contract efficiency can be improved by adding one more parameter. Specifically, we consider three two‐parameter contracts that are commonly used in reality: two‐part tariff contract, revenue‐sharing contract, and effort cost sharing contract. We find that the contract efficiency is improved under all the three contracts, but in different ways: the improvement in contract efficiency under each of them dominates the other two when manufacturer's quality improvement effectiveness is relatively low, moderate, and high, respectively. Furthermore, through numerical examples, we find that under some cases, a choice from these three two‐parameter contracts can achieve a close‐to‐perfect efficiency (>85%). Finally, we investigate whether a combination of the three two‐parameter contracts can achieve coordination. Interestingly, we find that only the combination of effort cost sharing contract and revenue‐sharing contract can achieve coordination, whereas combinations of either of them and two‐part tariff contract cannot.
Recursive circle packing problems
Authors: Pedroso João Pedro , Cunha Sílvia , Tavares João Nuno
Published: June 2014

This paper presents a class of packing problems where circles may be placed either inside or outside other circles, the whole set being packed in a rectangle. This corresponds to a practical problem of packing tubes in a container. Before being inserted in the container, tubes may be put inside other tubes in a recursive fashion. A variant of the greedy randomized adaptive search procedure is proposed for tackling this problem, and its performance is assessed in a set of benchmark instances.
Cementless Total Hip Replacement in 20 Juveniles Using BFX™ Arthroplasty
Authors: Fitzpatrick Noel , Law Andy Y. , Bielecki Malgorzata , Girling Sarah
Published: June 2014

Objective

To describe outcome after a minimum of 1 year for total hip replacement (THR) using BioMedtrix BFX™ biologic fixation implants in skeletally immature dogs (6–10 months of age).

Study Design

Case series.

Animals

Dogs (n = 20).

Methods

Medical records (November 2007–June 2010) of 20 dogs, 6–10 months old that had cementless THR were reviewed. Preoperative, immediate, 6‐week and >1‐year postoperative radiographs were compared. Clinical examination was performed at 6 weeks and >1 year postoperatively. Owner questionnaire was obtained at final follow‐up.

Results

Cementless THR using BFX™ implants was performed because of debilitating coxofemoral pain, resulting from canine hip dysplasia, after unsatisfactory outcome with medical management. Radiographs taken immediately, 6 weeks and at a mean of 29.8 months (range, 12–48 months) postoperatively revealed satisfactory implant positioning and stability. Significant change in measured cranial–caudal femoral stem fill and level (P < .001 and P = .006, respectively) were recorded at 6 weeks postoperatively without clinical significance. No further change in stem positioning occurred. Acetabular cup orientation remained unchanged throughout follow‐up. Complications requiring further surgical intervention were not encountered. One minor superficial infection was recorded and treated. Lameness and pain on manipulation of the affected hip had greatly improved in all dogs by 6 weeks postoperatively.

Conclusion

Cementless THR can safely be performed in skeletally immature dogs, providing satisfactory return to normal joint function and implant survivability for at least a mean of 29.8 months.
Cefazolin Concentration in Surgically Created Wounds Treated With Negative Pressure Wound Therapy Compared to Surgically Created Wounds Treated With Nonadherent Wound Dressings
Authors: Coutin Julia V. , Lanz Otto I. , Magnin‐Bissel Geraldine C. , Ehrich Marion F. , Miller Emily I. , Werre Stephen R. , Riegel Thomas O.
Published: June 2014

Objective

To compare cefazolin concentrations in biopsied tissue samples collected from surgically created wounds treated with negative pressure wound therapy to those collected from surgically created wounds treated with nonadherent dressings.

Study Design

Prospective, controlled, experimental study.

Animals

Adult female spayed Beagles (n = 12).

Methods

Full thickness cutaneous wounds were created on each antebrachium (n = 24). Immediately after surgery, cefazolin (22 mg/kg intravenously [IV]) was administered to each dog and continued every 8 hours during the study. The right wound was randomly assigned to group I or group II whereas the wound on the contralateral antebrachium was assigned to the other group. Group I wounds were treated with negative pressure wound therapy (NPWT) and group II wounds were treated with nonadherent dressings for 3 days. Dressings were changed and tissue biopsies obtained from wound beds at 24 hours intervals for both groups. Cefazolin wound tissue and plasma concentrations were measured by liquid chromatography mass spectrometry (LC–MS/MS). Blood samples for measuring plasma cefazolin concentrations were collected before biopsy sampling. At the time of surgery and at each subsequent bandage change, wound beds were swabbed and submitted for aerobic and anaerobic culture.

Results

After initiating cefazolin treatment, wound tissue antibiotic concentrations between treatment groups were not significantly different at any sampling time. Similarly, after initiating cefazolin treatment, plasma cefazolin concentrations were not significantly different at any sampling time for individual dogs.

Conclusions

Using a canine experimental model, NPWT treatment of surgically created wounds does not statistically impact cefazolin tissue concentrations when compared with conventional nonadherent bandage therapy.
Two‐Step Surgery Combining Standing Laparoscopy With Recumbent Ventral Median Celiotomy for Removal of Enlarged Pathologic Ovaries in 20 Mares
Authors: Vitte Amélie , Rossignol Fabrice , Mespoulhes‐Rivière Céline , Lechartier Antoine , Röecken Michael
Published: June 2014

Objectives

To report a combination of standing laparoscopic technique for intra‐abdominal dissection of the mesovarial pedicle followed by a limited ventral median celiotomy under general anesthesia for removal of enlarged ovaries in mares.

Study Design

Case series.

Animals

Mares (n = 20) aged 3–22 years with unilateral enlarged ovaries.

Methods

Enlarged ovaries were confirmed by transrectal palpation and ultrasonography. After sedation, 3 laparoscopic portals were made in the paralumbar fossa. The mesovarium was desensitized and dissected using a vessel sealing device, and the ovary was left free in the abdomen. Then under general anesthesia, the mare was positioned in dorsal recumbency and an 8 cm ventral median celiotomy made for ovary retrieval in a specimen bag.

Results

This 2‐step procedure was successfully used for removal enlarged ovaries (12–50 cm) in 17 mares and for management of behavioral problems in 3 mares. No operative or postoperative complications occurred. Owner satisfaction and cosmesis were considered excellent.

Conclusions

Standing laparoscopy combined with a limited median celiotomy is a safe technique for ovariectomy in mares. This technique mitigates most of the disadvantages of standing flank ovariectomy and a conventional open ventral median approach.
Evaluation of 3 Handheld Portable Analyzers for Measurement of L‐Lactate Concentrations in Blood and Peritoneal Fluid of Horses With Colic
Authors: Nieto Jorge E. , Dechant Julie E. , le Jeune Sarah S. , Snyder Jack R.
Published: June 2014

Objective

To compare 3 portable handheld analyzers with a bench top blood gas analyzer for measurement of blood and peritoneal fluid L‐lactate concentrations in horses admitted with signs of colic.

Study Design

Prospective clinical study.

Sample Population

Blood and peritoneal fluid from horses with colic.

Methods

L‐lactate concentrations in heparinized blood and peritoneal fluid were measured serially on 10 occasions to evaluate repeatability of the portable analyzers. Blood and peritoneal fluid L‐lactate concentrations were simultaneously evaluated by a bench top and 3 portable analyzers and the results compared by intraclass correlation coefficients and Bland Altman plots. L‐Lactate concentrations in a subgroup of peritoneal fluid samples were evaluated by a chromogenic laboratory assay and compared with the bench top and the handheld analyzers.

Results

Portable lactate analyzers had good intra‐analyzer reliability for peritoneal fluid. Two portable analyzers had poor intra‐analyzer reliability for mid concentrations of L‐lactate in blood. L‐lactate measurements from portable analyzers were closer to the bench top analyzer at low concentrations of L‐lactate than at higher concentrations. Compared with the bench top analyzer, the Lactate Pro and Lactate Plus have the highest intraclass correlation coefficient and the smallest bias for peritoneal fluid and blood L‐lactate, respectively. The bench top analyzer and the Lactate Pro had the highest level of agreement for peritoneal fluid compared with the chromogenic assay.

Conclusions

Although portable analyzers are alternatives for the measurement of L‐lactate concentration in field situations, clinicians need to be aware of the variable results between analyzers, especially when extrapolating means or cutoff values from studies using different lactate analyzers.
Elevation–diversity patterns through space and time: ant communities of the Maloti‐Drakensberg Mountains of southern Africa
Authors: Bishop Tom R. , Robertson Mark P. , van Rensburg Berndt J. , Parr Catherine L.
Published: June 2014

Aim

Patterns of biological diversity are often investigated across space but little work has attempted to explore the consistency of such observations through time. Here, our aim was to understand the patterns of diversity for a functionally critical taxon, the ants (Hymenoptera: Formicidae), through space and time using an extensive dataset collected across an elevational gradient. In addition, we evaluated the importance of two key postulated drivers of elevational diversity patterns: temperature and available area.

Location

The Maloti‐Drakensberg Mountains of southern Africa.

Methods

We sampled epigaeic ant communities biannually for 7 years (2006–2012) at eight different elevational sites. We then used an information theoretic approach combined with generalized linear mixed models to: (1) describe diversity patterns through space and time; (2) assess the importance of different abiotic drivers; and (3) understand how much spatio‐temporal variation can be explained by these drivers. Simple regression approaches were also used to test for differences in seasonal variation along the elevational gradient.

Results

We found clear mid‐elevational peaks of species density and evenness measures. Abundance patterns were complex. The spatial distributions of all three metrics changed across seasons and years. Temperature variables had important roles in explaining both species density and abundance patterns, whilst species density was also influenced by available area. In conjunction, we found much greater seasonal variability in species density at low elevations. This variation was independent of differences in species pool size.

Main conclusions

We found patterns of ant diversity that are strongly modulated by temporal change. There was a consistent and strong signature of seasonality on the elevation–diversity patterns of the ants, whilst annual changes throughout the study period had a weaker influence. We conclude that both spatial and temporal patterns are driven primarily by temperature, with only a weak influence of available elevational area. This study is the first to describe the spatio‐temporal distribution of a suite of community‐level metrics along an elevational gradient and implies that temporal variation should be considered more carefully in studies of invertebrate diversity, particularly with respect to elevation and the mechanisms that may be maintaining diversity patterns.
Microbial diversity and community–environment relationships in boreal streams
Authors: Heino Jani , Tolkkinen Mikko , Pirttilä Anna Maria , Aisala Heidi , Mykrä Heikki
Published: June 2014

Aim

The perspective that microbial communities are controlled solely by environmental factors (‘everything is everywhere, but the environment selects’) has persisted for a long time, notwithstanding that recent studies have found that both environmental factors and spatial processes are important. We examined variation in the structure of fungal and bacterial communities in boreal streams along large local environmental gradients (e.g. stream size, acidity and nutrients) at intermediate spatial extent. Owing to the intermediate spatial extent of our study area and high dispersal rates of microbes, we expected that local environmental factors would structure stream fungal and bacterial communities.

Location

A set of 30 streams was sampled along a geographical transect from western to eastern Finland.

Methods

Leaf packs were used as sampling units in each stream. Fungal and bacterial operational taxonomic units (OTUs) were determined using pyrosequencing in the laboratory. Species accumulation curves were used to assess how well the regional species pools were sampled. Partial redundancy analysis and partial linear regression were used to determine the relative contributions of environmental and spatial variables to community structure and OTU richness, respectively.

Results

We found that environmental control was important in structuring fungal and bacterial communities, yet much of the variation was attributable to the shared effects of environmental and spatial predictors, or remained unexplained. The composition of fungal and bacterial communities was most strongly related to water chemistry variables (i.e. pH, aluminium and total phosphorus), whereas habitat variables (i.e. riparian deciduous trees, moss cover, substratum particle size and stream width) were clearly less important. We also found that fungal richness was negatively related to water iron concentration, whereas bacterial richness showed only a weak relationship with water pH.

Main conclusions

The composition and richness of stream microbial communities are mostly related to water chemistry variables at the spatial extent studied, emphasizing an important role for species sorting. This finding supports the traditional perspective that local environmental conditions are important drivers of variation in microbial communities. However, much of the variation in fungal and bacterial communities remained unexplained, suggesting that drivers of these communities are likely to be complex and not yet fully understood.
Parental psychopathology in families of children with attention‐deficit/hyperactivity disorder and exposed to maternal smoking during pregnancy
Authors: Sengupta Sarojini M. , Fortier Marie‐Ève , Thakur Geeta A. , Bhat Venkat , Grizenko Natalie , Joober Ridha
Published: June 2014

Background

Both genetic and environmental factors have been implicated in the etiology of attention‐deficit/hyperactivity disorder (ADHD). We had previously suggested that exposure to maternal smoking during pregnancy (MSDP) may be a valid basis for delineating a distinct subtype of ADHD, where children exposed to MSDP present with a more severe clinical picture. Here, we examine the psychopathology of parents in this group, to better understand the etiology of ADHD.

Methods

Using the Family Interview for Genetic Studies in a sample of 514 families of children with ADHD, we collected data pertaining to lifetime parental psychopathology. Families were stratified based on maternal smoking during the complete gestational period. The frequency of different disorders was compared using the χ2 statistic.

Results

In the group where mothers smoked during pregnancy, both parents were significantly more likely to have antisocial personality disorder, and problems with alcohol and drug abuse. Mothers had a significantly higher frequency of major depressive disorder (MDD), while fathers showed a trend for both MDD and bipolar disorder.

Conclusions

Based on the pattern of psychopathology in parents of children exposed to MSDP, as well as earlier reports of the severe clinical, behavioral, and cognitive phenotype in these children, combined with the large body of epidemiological evidence, we propose that these children present a distinct subtype of ADHD with comorbid conduct disorder. Furthermore, we propose that MSDP may be a proxy measure to help delineate this subtype.
Interaction effects of cell diffusion, cell density and public goods properties on the evolution of cooperation in digital microbes
Authors: Dobay A. , Bagheri H. C. , Messina A. , Kümmerli R. , Rankin D. J.
Published: June 2014

Microbial cooperation typically consists in the sharing of secreted metabolites (referred to as public goods) within the community. Although public goods generally promote population growth, they are also vulnerable to exploitation by cheating mutants, which no longer contribute, but still benefit from the public goods produced by others. Although previous studies have identified a number of key factors that prevent the spreading of cheaters, little is known about how these factors interact and jointly shape the evolution of microbial cooperation. Here, we address this issue by investigating the interaction effects of cell diffusion, cell density, public good diffusion and durability (factors known to individually influence costs and benefits of public goods production) on selection for cooperation. To be able to quantify these effects across a wide parameter space, we developed an individual‐based simulation platform, consisting of digital cooperator and cheater bacteria inhabiting a finite two‐dimensional continuous toroidal surface. Our simulations, which closely mimic microbial microcolony growth, revealed that: (i) either reduced cell diffusion (which keeps cooperators together) or reduced public good diffusion (which keeps the public goods closer to the producer) is not only essential but also sufficient for cooperation to be promoted; (ii) the sign of selection for or against cooperation can change as a function of cell density and in interaction with diffusion parameters; and (iii) increased public goods durability has opposing effects on the evolution of cooperation depending on the level of cell and public good diffusion. Our work highlights that interactions between key parameters of public goods cooperation give rise to complex fitness landscapes, a finding that calls for multifactorial approaches when studying microbial cooperation in natural systems.
Morphology and Molecular Phylogeny of Apoterritricha lutea n. g., n. sp. (Ciliophora, Spirotrichea, Hypotrichia): A Putative Missing Link Connecting Cyrtohymena and Afrokeronopsis
Authors: Kim Ji Hye , Vďačný Peter , Shazib Shahed Uddin Ahmed , Shin Mann Kyoon
Published: June 2014

A new hypotrichous ciliate, Apoterritricha lutea n. g., n. sp., was discovered in a sample of a terrestrial liverwort from Korea. Its morphology was studied using detailed in vivo observation and protargol impregnation. Its phylogenetic relationships were revealed by analyses of the 18S rRNA gene. This new taxon is characterized by a combination of the following traits: (i) ellipsoidal to narrowly ellipsoidal body with an average size of 230 × 85 μm; (ii) two macronuclear nodules and two to five micronuclei; (iii) golden yellow cortical granules, forming small groups along the microtubular appendages of cirri, adoral membranelles, and dorsal kineties; (iv) typically three frontal cirri, one buccal cirrus, four frontoventral cirri, seven midventral cirri, two pretransverse cirri, seven transverse cirri, ca. 38 left, and ca. 36 right marginal cirri; and (v) on average six dorsal kineties, three dorsomarginal kineties, and three caudal cirri. In molecular phylogenies, A. lutea clusters with strong support within a clade containing Afrokeronopsis aurea and several “typical” oxytrichids having golden yellow to brown cortical granules. In this light we propose a hypothesis that is not unambiguously rejected by the present phylogenetic analyses, which shows how the Afrokeronopsis‐like pattern could have evolved from a Rubrioxytricha‐like ancestor via an Apoterritricha‐like stage by cirri‐multiplication.
Changes in Daily Activity Patterns with Age in U.S. Men and Women: National Health and Nutrition Examination Survey 2003–04 and 2005–06
Authors: Martin Kathryn R. , Koster Annemarie , Murphy Rachel A. , Van Domelen Dane R. , Hung Ming‐yang , Brychta Robert J. , Chen Kong Y. , Harris Tamara B.
Published: June 2014

Objectives

To compare daily and hourly activity patterns according to sex and age.

Design

Cross‐sectional, observational.

Setting

Nationally representative community sample: National Health and Nutrition Examination Survey (NHANES) 2003–04 and 2005–06.

Participants

Individuals (n = 5,788) aged 20 and older with 4 or more valid days of monitor wear‐time, no missing data on valid wear‐time minutes, and covariates.

Measurements

Activity was examined as average counts per minute (CPM) during wear‐time; percentage of time spent in nonsedentary activity; and time (minutes) spent in sedentary (<100 counts), light (100–759), and moderate to vigorous physical activity (MVPA (≥760)). Analyses accounted for survey design, adjusted for covariates, and were sex specific.

Results

In adjusted models, men spent slightly more time (~1–2%) in nonsedentary activity than women aged 20 to 34, with levels converging at age 35 to 59, although the difference was not significant. Women aged 60 and older spent significantly more time (~3–4%) in nonsedentary activity than men, despite similarly achieved average CPM. With increasing age, all nonsedentary activity decreased in men; light activity remained constant in women (~30%). Older men had fewer CPM at night (~20), more daytime sedentary minutes (~3), fewer daytime light physical activity minutes (~4), and more MVPA minutes (~1) until early evening than older women.

Conclusion

Although sex differences in average CPM declined with age, differences in nonsedentary activity time emerged as men increased sedentary behavior and reduced MVPA time. Maintained levels of light‐intensity activity suggest that women continue engaging in common daily activities into older age more than men. Findings may help inform the development of behavioral interventions to increase intensity and overall activity levels, particularly in older adults.