bluuebunny/crossref_metadata_2025 huggingface dataset:
Rates of Intraperitoneal Temperature Change in Lake Trout Implanted with Archival Tags
Authors: Negus Mary T. , Bergstedt Roger A.
Published: March 2012

The rates of change in the intraperitoneal temperature of lake trout Salvelinus namaycush weighing between 817 g and 2,230 g were examined in the laboratory. Nine lake trout implanted with archival tags were moved between three tanks containing different water temperatures. The intraperitoneal temperatures recorded by the archival tags lagged behind the external temperatures when these thermal changes were encountered, but the smallest fish shifted temperature about twice as fast as the largest fish. The rate of core temperature change can be described by Newton's law of cooling, which states that the rate of temperature change of an object is proportional to the difference between its own temperature and the ambient temperature. This time lag can provide ample opportunity for fish to make brief forays into water temperatures outside an optimal range, while experiencing minimal change in intraperitoneal temperature. The relationship between the rate of temperature change and body mass varies with the body shape and the location where measurements are taken. The rate of thermal exchange was calculated from each temperature trial, and a regression derived from the log–log plot of these rates versus body mass was used to determine a standardized rate of thermal exchange for lake trout of any body mass within the range tested.
Thirty-Five Questions
Authors: Mortensen Peter
Published: March 2012

The research projects upon which Hallenbeck, Olson, Solberg, and Wang reflect raise challenging questions about the location of and boundaries around their archival sources. The authors' reflections prompt my inquiry into how access to these sources might be affected by the socioeconomic and technological developments that are reshaping academe.
Constructing Unit-Specific Empiric Treatment Guidelines for Catheter-Related and Primary Bacteremia by Determining the Likelihood of Inadequate Therapy
Authors: Davis Megan E. , Anderson Deverick J. , Sharpe Michelle , Chen Luke F. , Drew Richard H.
Published: March 2012

This study aimed to determine the feasibility of using likelihood of inadequate therapy (LIT), a parameter calculated by using pathogen frequency and in vitro susceptibility for determination of appropriate empiric antibiotic therapy for primary bloodstream infections. Our study demonstrates that LIT may reveal differences in traditional antibiograms.
Implementation of an Antimicrobial Stewardship Program at a 60-Bed Long-Term Acute Care Hospital
Authors: Pate Perry G. , Storey Donald F. , Baum Donna L.
Published: March 2012

We implemented an antimicrobial stewardship program at an urban, 60-bed long-term acute care hospital using a strategy of weekly postprescriptive chart audit with intervention and feedback. The results for the first 15 months demonstrated 80% acceptance of recommendations, a 21% reduction in use, and a 28% reduction in cost per patient-day.
Rates and Appropriateness of Antimicrobial Prescribing at an Academic Children's Hospital, 2007–2010
Authors: Levy E. R. , Swami S. , Dubois S. G. , Wendt R. , Banerjee R.
Published: March 2012

Objective and Design.

Antimicrobial use in hospitalized children has not been well described. To identify targets for antimicrobial stewardship interventions, we retrospectively examined pediatric utilization rates for 48 antimicrobials from 2007 to 2010 as well as appropriateness of vancomycin and cefepime use in 2010.

Patients and Setting.

All children hospitalized between 2007 and 2010 at the Mayo Clinic Children's Hospital, a 120-bed facility within a larger adult hospital in Rochester, Minnesota.

Methods.

We calculated antimicrobial utilization rates in days of therapy per 1,000 patient-days. Details of vancomycin and cefepime use in 2010 were abstracted by chart review. Two pediatric infectious disease physicians independently assessed appropriateness of antibiotic use.

Results.

From 2007 to 2010, 9,880 of 17,242 (57%) hospitalized children received 1 or more antimicrobials. Antimicrobials (days of therapy per 1,000 patient-days) used most frequently in 2010 were cefazolin (97.8), vancomycin (97.1), fluconazole (76.4), piperacillin-tazobactam (70.7), and cefepime (67.6). Utilization rates increased significantly from 2007 to 2010 for 10 antimicrobials, including vancomycin, fluconazole, piperacillin-tazobactam, cefepime, trimethoprim-sulfamethoxazole, caspofungin, and cefotaxime. In 2010, inappropriate use of vancomycin and cefepime was greater in the pediatric intensive care unit than ward (vancomycin: 17.8% vs 6.4%,P= .001; cefepime: 9.2% vs 3.9%,P= .142) and on surgical versus medical services (vancomycin: 20.5% vs 8.0%,P= .001; cefepime: 19.4% vs 3.4%,P≤ .001). The most common reason for inappropriate antibiotic use was failure to discontinue or de-escalate therapy.

Conclusions.

In our children's hospital, use of 10 antimicrobials increased during the study period. Inappropriate use of vancomycin and cefepime was greatest on the critical care and surgical services, largely as a result of failure to de-escalate therapy, suggesting targets for future antimicrobial stewardship interventions.
Impact of the Use of Procalcitonin Assay in Hospitalized Adult Patients with Pneumonia at a Community Acute Care Hospital
Authors: Kook Janet L. , Chao Stephanie R. , Le Jennifer , Robinson Philip A.
Published: March 2012

A retrospective, quasi-experimental cohort study compared antibiotic use before and after implementation of a procalcitonin assay at a community acute care hospital. This study demonstrated that the implementation of the procalcitonin assay was associated with a decrease in antibiotic days of therapy in adult patients with pneumonia.
Evaluation of Postprescription Review and Feedback as a Method of Promoting Rational Antimicrobial Use: A Multicenter Intervention
Authors: Cosgrove Sara E. , Seo Susan K. , Bolon Maureen K. , Sepkowitz Kent A. , Climo Michael W. , Diekema Daniel J. , Speck Kathleen , Gunaseelan Vidhya , Noskin Gary A. , Herwaldt Loreen A. , Wong Edward , Perl Trish M. ,   CDC Prevention Epicenter Program
Published: March 2012

Objective.

To evaluate the impact of postprescription review of broad-spectrum antimicrobial (study-ABX) agents on rates of antimicrobial use.

Design.

Quasi-experimental before-after study.

Setting.

Five academic medical centers.

Patients.

Adults receiving at least 48 hours of study-ABX.

Methods.

The baseline, intervention, and follow-up periods were 6 months each in 2 units at each of 5 sites. Adults receiving at least 48 hours of study-ABX entered the cohort as case-patients. During the intervention, infectious-diseases physicians reviewed the cases after 48 hours of study-ABX. The provider was contacted with alternative recommendations if antimicrobial use was considered to be unjustified on the basis of predetermined criteria. Acceptance rates were assessed 48 hours later. The primary outcome measure was days of study-ABX per 1,000 study-patient-days in the baseline and intervention periods.

Results.

There were 1,265 patients in the baseline period and 1,163 patients in the intervention period. Study-ABX use decreased significantly during the intervention period at 2 sites: from 574.4 to 533.8 study-ABX days/1,000 patient-days (incidence rate ratio [IRR], 0.93; 95% confidence interval [CI], 0.88-0.97; P = .002) at hospital В and from 615.6 to 514.4 study-ABX days/1,000 patient-days (IRR, 0.83; 95% CI, 0.79-0.88; P < .001) at hospital D. Both had established antimicrobial stewardship programs (ASP). Study-ABX use increased at 2 sites and stayed the same at 1 site. At all institutions combined, 390 of 1,429 (27.3%) study-ABX courses were assessed as unjustified; recommendations to modify or stop therapy were accepted for 260 (66.7%) of these courses.

Conclusions.

Postprescription review of study-ABX decreased antimicrobial utilization in some of the study hospitals and may be more effective when performed as part of an established ASP.
JOINT ANALYSIS OF X-RAY AND SUNYAEV–ZEL'DOVICH OBSERVATIONS OF GALAXY CLUSTERS USING AN ANALYTIC MODEL OF THE INTRACLUSTER MEDIUM
Authors: Hasler Nicole , Bulbul Esra , Bonamente Massimiliano , Carlstrom John E. , Culverhouse Thomas L. , Gralla Megan , Greer Christopher , Hawkins David , Hennessy Ryan , Joy Marshall , Kolodziejczak Jeffery , Lamb James W. , Landry David , Leitch Erik M. , Mantz Adam , Marrone Daniel P. , Miller Amber , Mroczkowski Tony , Muchovej Stephen , Plagge Thomas , Pryke Clem , Woody David
Published: March 2012

We perform a joint analysis of X-ray and Sunyaev–Zel'dovich effect data using an analytic model that describes the gas properties of galaxy clusters. The joint analysis allows the measurement of the cluster gas mass fraction profile and Hubble constant independent of cosmological parameters. Weak cosmological priors are used to calculate the overdensity radius within which the gas mass fractions are reported. Such an analysis can provide direct constraints on the evolution of the cluster gas mass fraction with redshift. We validate the model and the joint analysis on high signal-to-noise data from the Chandra
X-ray Observatory and the Sunyaev–Zel'dovich Array for two clusters, A2631 and A2204.
One-pot synthesis of PVA-capped silver nanoparticles their characterization and biomedical application
Authors: Patil Rupali S , Kokate Mangesh R , Jambhale Chitra L , Pawar Sambhaji M , Han Sung H , Kolekar Sanjay S
Published: March 2012

The rapid one-pot synthesis of silver nanoparticles (SNPs) at room temperature by using hydrazine hydrate as reducing agent and polyvinyl alcohol as stabilizing agent is reported. The SNPs were characterized with UV-visible (UV-Vis) spectroscopy, x-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), atomic force microscopy (AFM) and transmission electron microscopy (TEM). The synthesized silver nanoparticle shows surface plasmon resonance at 410 nm. The XRD reveals face-centered cubic (FCC) structure of SNPs. FE-SEM, AFM and TEM show that nanoparticles have spherical morphology with diameters in the range of 10–60 nm. The antimicrobial activity of synthesized hybrid material against strains of four different bacteria (Bacillus cereus, Escherichia coli, Staphylococus aureus, Proteus vulgaris), that are commonly found in hospitals has been studied. The results indicate that such particles have potential applications in biotechnology and biomedical science.
Tabulation of cubic function fields via polynomial binary cubic forms
Authors: Rozenhart Pieter , Jr. Michael Jacobson , Scheidler Renate
Published: March 2012

We present a method for tabulating all cubic function fields overFq(t)\mathbb {F}_q(t)whose discriminantDDhas either odd degree or even degree and the leading coefficient of−3D-3Dis a non-square inFq∗\mathbb {F}_{q}^*, up to a given boundBBondeg⁡(D)\deg (D). Our method is based on a generalization of Belabas’ method for tabulating cubic number fields. The main theoretical ingredient is a generalization of a theorem of Davenport and Heilbronn to cubic function fields, along with a reduction theory for binary cubic forms that provides an efficient way to compute equivalence classes of binary cubic forms. The algorithm requiresO(B4qB)O(B^4 q^B)field operations asB→∞B \rightarrow \infty. The algorithm, examples and numerical data forq=5,7,11,13q=5,7,11,13are included.
Elliptic 𝐾3 surfaces with 𝐩^{𝐧}-torsion sections
Authors: Ito Hiroyuki , Liedtke Christian
Published: March 2012

We classify elliptic K3 surfaces in characteristicppwithpnp^n-torsion section. Forpn≥3p^n\geq 3we verify conjectures of Artin and Shioda, compute the heights of their formal Brauer groups, as well as Artin invariants and Mordell–Weil groups in the supersingular cases.
Seasonal dynamics of growth and mortality suggest contrasting population structure and ecology for cod, pollack, and saithe in a Norwegian fjord
Authors: Heino Mikko , Svåsand Terje , Nordeide Jarle Tryti , Otterå Håkon
Published: March 2012

Heino, M., Svåsand, T., Nordeide, J. T., Otterå, H. 2012. Seasonal dynamics of growth and mortality suggest contrasting population structure and ecology for cod, pollack, and saithe in a Norwegian fjord. – ICES Journal of Marine Science, 69: 537–546. We study the dynamics of Atlantic cod (Gadus morhua L.), pollack (Pollachius pollachius L.), and saithe (Pollachius virens L.) in Masfjorden, a small fjord in western Norway. Annually, cohorts of pollack and cod grow in size and decline in abundance, as expected of closed populations, whereas saithe virtually disappear before maturity. Seasonally, in contrast, the dynamics of cod and pollack differ. Pollack shows a regular growth pattern, with most of the growth taking place in summer. Its abundance-at-age shows strong seasonal variations, with a marked increase from spring to summer followed by a decline through autumn and winter. These patterns relate partly to seasonal changes in depth distribution and catchability. Combined with the observation that spawning-stage pollack are abundant in spring, we interpret these patterns to suggest that pollack in Masfjorden represent a dynamically independent unit. Seasonal changes in abundance are less marked for cod, and seasonal changes in depth distribution seem insignificant. However, cod shows an unusual pattern in length at age, with no apparent growth in summer and fast growth in autumn. These patterns suggest that the population structure of cod may be more open than that of pollack and may involve mixing of more than one population component.
Molecular Characterization and Functional Analysis of a Necrosis- and Ethylene-Inducing, Protein-Encoding Gene Family from Verticillium dahliae
Authors: Zhou Bang-Jun , Jia Pei-Song , Gao Feng , Guo Hui-Shan
Published: March 2012

Verticillium dahliae Kleb. is a hemibiotrophic, phytopathogenic fungus that causes wilt disease in a wide range of crops, including cotton. Successful host colonization by hemibiotrophic pathogens requires the induction of plant cell death to provide the saprophytic nutrition for the transition from the biotrophic to the necrotrophic stage. In this study, we identified a necrosis-inducing Phytophthora protein (NPP1) domain–containing protein family containing nine genes in a virulent, defoliating isolate of V. dahliae (V592), named the VdNLP genes. Functional analysis demonstrated that only two of these VdNLP genes, VdNLP1 and VdNLP2, encoded proteins that were capable of inducing necrotic lesions and triggering defense responses in Nicotiana benthamiana, Arabidopsis, and cotton plants. Both VdNLP1 and VdNLP2 induced the wilting of cotton seedling cotyledons. However, gene-deletion mutants targeted by VdNLP1, VdNLP2, or both did not affect the pathogenicity of V. dahliae V592 in cotton infection. Similar expression and induction patterns were found for seven of the nine VdNLP transcripts. Through a comparison of the conserved amino acid residues of VdNLP with different necrosis-inducing activities, combined with mutagenesis-based analyses, we identified several novel conserved amino acid residues, in addition to the known conserved heptapeptide GHRHDWE motif and the cysteine residues of the NPP domain–containing protein, that are indispensable for the necrosis-inducing activity of the VdNLP2 protein.
The awr Gene Family Encodes a Novel Class of Ralstonia solanacearum Type III Effectors Displaying Virulence and Avirulence Activities
Authors: Solé Montserrat , Popa Crina , Mith Oriane , Sohn Kee Hoon , Jones Jonathan D. G. , Deslandes Laurent , Valls Marc
Published: March 2012

We present here the characterization of a new gene family, awr, found in all sequenced Ralstonia solanacearum strains and in other bacterial pathogens. We demonstrate that the five paralogues in strain GMI1000 encode type III-secreted effectors and that deletion of all awr genes severely impairs its capacity to multiply in natural host plants. Complementation studies show that the AWR (alanine-tryptophan-arginine tryad) effectors display some functional redundancy, although AWR2 is the major contributor to virulence. In contrast, the strain devoid of all awr genes (Δawr1-5) exhibits enhanced pathogenicity on Arabidopsis plants. A gain-of-function approach expressing AWR in Pseudomonas syringae pv. tomato DC3000 proves that this is likely due to effector recognition, because AWR5 and AWR4 restrict growth of this bacterium in Arabidopsis. Transient overexpression of AWR in nonhost tobacco species caused macroscopic cell death to varying extents, which, in the case of AWR5, shows characteristics of a typical hypersensitive response. Our work demonstrates that AWR, which show no similarity to any protein with known function, can specify either virulence or avirulence in the interaction of R. solanacearum with its plant hosts.
First Report of Orobanche aegyptiaca Parasitism on Sesame in Iran
Authors: Teimoury M. , Karimmojeni H. , Ehtemam M. H. , Mehri H. R.
Published: March 2012

A field survey revealed infestations of broomrape, Orobanche aegyptiaca (syn. Phelipanche aegyptiaca), on sesame (Sesamum indicum L.) plants in the province of Khorasan (36°12'N, 57°39'E, 972 m above sea level) in northeastern Iran in November 2011. About 5% of total sesame fields in this area were infested, and the estimated average yield losses were approximately 30 to 40%. The annual mean air temperature and the average maximum and minimum air temperatures were 17.5, 24.2, and 10.6°C, respectively. In a pot experiment that was also conducted at the Isfahan University of Technology to study the effect of sesame as a trap crop for managing broomrape, a total of 20 genotypes of sesame were infested with broomrape. The infestation of sesame was confirmed by verifying the attachment of the broomrape to the sesame roots. Broomrape plant heights were between 20 and 35 cm, with flowering stems 15 to 20 cm. The stems were erect, usually branched, slender, glandular-pubescent, pale yellowish, and inflorescent rather than lax. Flowers had one bract and two bracteoles. The bracts measured 6 to 8 mm, had ovate lanceolates shorter than the calyces, and filiform, lanceolate bracteoles measuring 8 mm. The calyces measured 10 to 11 mm, and were gamosepalous, entire, whitish, hairy, and glandular. Corollas measured 32 to 35 mm, and were blue violet or sky blue with darker veins and cream proximally, straight or slightly curved, conspicuously infundibuliform in distal parts, and glandular-pubescent with two lips. Stamens were epipetalous, inserted 4 to 5 mm above the corolla base, with filaments hairy below, sparsely so above; anthers were villous or spidery hairy along sutures. Stigma lobes were white. The Botanists Group of the College of Agriculture of IUT confirmed the plants' identity. Sesame has been mentioned before as a trap crop for broomrape (1); however, to our knowledge, this is the first report of broomrape parasitism on sesame in Iran.

Reference: (1) B. M. Chittapur et al. Allelopathy J. 8:147, 2001.
Citrus Responses to Xylella fastidiosa Infection
Authors: Garcia A. L. , Torres S. C. Z. , Heredia M. , Lopes S. A.
Published: March 2012

The xylem-limited bacterium Xylella fastidosa causes the widely disseminated citrus variegated chlorosis disease (CVC). In Brazil, CVC has been known for more than 20 years and affects only sweet orange. Lime and mandarin have remained free of symptoms despite the high inoculum pressure. Knowing the mechanisms underlying this apparent resistance is important to devise new disease control strategies. The reaction of commercial sweet orange (‘Caipira’, ‘Natal’, ‘Pêra’, and ‘Valencia’), lime (Mexican and Persian), mandarin (‘Cleopatra’, ‘Cravo’, ‘Ponkan’, and ‘Sunki’), and the acid citrus species Rangpur to X. fastidiosa was compared in artificially inoculated seedlings, which were assessed for symptom expression, pathogen isolation, and the amount of apparently occluded xylem vessels in cross-sectioned leaf petioles. Only the sweet orange expressed typical CVC symptoms, varying from 53.8% in Valencia to 63.0% in Caipira. Average percentages of positive isolations (pi) and occluded vessels (ov) were higher in sweet orange (pi= 59.2 to 75.0; ov = 10.7 to 25.8) than mandarin (pi = 2.3 to 16.3; ov = 1.4 to 4.0), lime (pi = 0 to 5.4; ov = 0 to 2.1), or Rangpur (pi = 1,9; ov = 1.1). There were no obvious differences in xylem anatomy among all citrus varieties, suggesting that the mechanisms of resistance to CVC are not related to any physical variation in xylem structure.
First Report of Anthracnose Caused by Colletotrichum gloeosporioides on Cymbidium sinense in China
Authors: Huang J. H. , Shi Z. R. , Zhang Y. X. , Xiang M. M.
Published: March 2012

Cymbidium sinense are among the most important commercial orchids cultivated in China for flower production. In April of 2010, a leaf spot was sporadically observed on C. sinense in fields located in Guangzhou, China. Symptoms first appeared as yellow to brown, irregular-shaped lesions on the leaf margin or tip. As the infection continued on the tissues, the spot expanded and became dark brown along the margins and developed gray brown centers. At later stages, numerous epidermal acervuli developed on the lesions and mucilaginous conidial masses appeared on the lesions under moist conditions. Ten samples from tissue along the margins of lesions were collected and surface sterilized by washing in 70% ethanol for 30 s, followed by washing in 1% sodium hypochlorite for 30 s, and rinsing in sterile distilled water. These samples were plated onto potato dextrose agar (PDA) and incubated at 25°C with a 12-h alternating light and dark cycle. After 5 days, fungal colonies that grew from the tissue were subcultured onto PDA and pure cultures were obtained using the single-spore method. The fungus was identified as Colletotrichum gloeosporioides based on typical cultural characteristics and conidial morphology (1). PDA cultures were white at first and subsequently became grayish white to gray and pink to reddish brown. Conidia were straight, one-celled, hyaline, oblong, or cylindrical, slightly curved with truncate base and rounded apex and measured 14.0 to 19.5 × 4.0 to 6.0 μm. Chlamydospores, sclerotia, and a teleomorph were not found. Genomic DNA was extracted from one isolate and the internal transcribed spacer (ITS) region of the ribosomal DNA (ITS1-5.8S-ITS2) was amplified using ITS1 (5′-TCCGTAGGTGAACCTGCGG-3′) and ITS4 (5′-CCTCCGCTTATTGATATGC-3′) primers. The ITS region was further cloned and sequenced and showed 100% homology with many GenBank sequences (e.g., HQ333546.1) of C. gloeosporioides as the closest match. Pathogenicity tests were done by transferring one 4-mm-diameter disk of PDA that was colonized by the test isolates to wounds (4 × 4 mm) made with a needle in the leaves of 1-year-old C. sinense plants. Control plants received a sterile agar plug in wound. Ten inoculated plants were covered with plastic bags to maintain a high relative humidity and maintained in a greenhouse at 25 ± 2°C for 72 h. Five days after inoculation, no symptoms developed on the control plants. Foliar lesions closely resembled those observed in the field. C. gloeosporioides was reisolated consistently from symptomatic tissue collected from greenhouse experiments. To our knowledge, this is the first report of C. gloeosporioides causing anthracnose on C. sinense in China.

Reference: (1) B. C. Sutton. Colletotrichum Biology, Pathology and Control. CAB International, Wallingford, UK, 1992.
Gabapentin Inhibits Catecholamine Release from Adrenal Chromaffin Cells
Authors: Todd Robert D. , McDavid Sarah M. , Brindley Rebecca L. , Jewell Mark L. , Currie Kevin P. M.
Published: March 2012

Background

Gabapentin is most commonly prescribed for chronic pain, but acute perioperative effects, including preemptive analgesia and hemodynamic stabilization, have been reported. Adrenal chromaffin cells are a widely used model to investigate neurosecretion, and adrenal catecholamines play important physiologic roles and contribute to the acute stress response. However, the effects of gabapentin on adrenal catecholamine release have never been tested.

Methods

Primary cultures of bovine adrenal chromaffin cells were treated with gabapentin or vehicle for 18-24 h. The authors quantified catecholamine secretion from dishes of cells using high-performance liquid chromatography and resolved exocytosis of individual secretory vesicles from single cells using carbon fiber amperometry. Voltage-gated calcium channel currents were recorded using patch clamp electrophysiology and intracellular [Ca2+] using fluorescent imaging.

Results

Gabapentin produced statistically significant reductions in catecholamine secretion evoked by cholinergic agonists (24 ± 3%, n = 12) or KCl (16 ± 4%, n = 8) (mean ± SEM) but did not inhibit Ca2+ entry or calcium channel currents. Amperometry (n = 51 cells) revealed that gabapentin inhibited the number of vesicles released upon stimulation, with no change in quantal size or kinetics of these unitary events.

Conclusions

The authors show Ca2+ entry was not inhibited by gabapentin but was less effective at triggering vesicle fusion. The work also demonstrates that chromaffin cells are a useful model for additional investigation of the cellular mechanism(s) by which gabapentin controls neurosecretion. In addition, it identifies altered adrenal catecholamine release as a potential contributor to some of the beneficial perioperative effects of gabapentin.
The Use of Adipose Tissue–Derived Stem Cells within a Dermal Substitute Improves Skin Regeneration by Increasing Neoangiogenesis and Collagen Synthesis
Authors: Meruane Manuel A. , Rojas Mariana , Marcelain Katherine
Published: March 2012

Background:

Surgical treatment of injuries with loss of skin tissue has improved significantly with the advent of regenerative medicine and tissue bioengineering, and the use of stem cells and dermal substitutes. The success of tissue regeneration depends on optimal local vascularization and the successful integration of the artificial skin. The present study combines the use of autologous adipose-derived stem cells with a commercially available dermal substitute (Integra) for skin regeneration.

Methods:

Adipose-derived stem cells were isolated from the inguinal region of eight Sprague-Dawley adult rats, seeded onto a piece of dermal substitute for 48 hours, and then implanted into the same rat, followed by comparison of the evolution with a contralateral implant without adipose-derived stem cells. After 1, 2, and 3 weeks of regeneration in vivo, implants were removed for histologic evaluation.

Results:

Adipose-derived stem cells adhere properly to the dermal matrix, and autologous tissue integration in the rat was good. The histologic evaluation showed that adipose-derived stem cells significantly increased microvascular density (7.7 ± 0.6 percent versus 5.3. ± 0.5 percent, as assessed by immunohistochemical staining of factor VIII) and the synthesis of collagen type I (24 ± 3 percent versus 16 ± 2 percent, as assessed by Sirius red staining). Although there was greater epithelialization on the side treated with adipose-derived stem cells (2530 ± 939 μm versus 1911 ± 763 μm), as assessed by anticytokeratin immunohistochemistry staining 34βE12, this difference was not statistically significant.

Conclusions:

The authors' data suggest that the seeding of adipose-derived stem cells onto a dermal substitute improves skin regeneration and tissue integration by increasing vascularity and collagen synthesis. Further studies are necessary to achieve complete epithelialization with the use of adipose-derived stem cells.
The Survival Curve
Authors: Selber Jesse Creed , Angel Soto-Miranda Miguel , Liu Jun , Robb Geoff
Published: March 2012

Background:

When vascular compromise is detected, a free flap is immediately taken back to the operating room for attempted salvage. Which factors predict the success or failure of a take-back is currently unknown.

Methods:

A review of free flaps performed at a single institution over the last 10 years was performed. A total of 4965 flaps were identified, and an analysis of factors predicting salvage or failure of first, second, and third take-backs for microvascular complications was performed.

Results:

Of 4965 flaps, 517 (10.3 percent) required return to the operating room, 157 (3.34 percent) for vascular complications. There were 66 (1.41 percent) total flap failures. Of 157 take-backs, 102 required return once, 44 twice, and 11 three times, with salvage rates of 72, 34, and 27 percent, respectively (p < 0.01). Overall salvage rate was 58 percent. The probability of a flap going back for a second time was 35 percent. Risks for flap failure included thrombotic (35.1 percent) versus mechanical (8 percent) etiology (p = 0.01) and arterial (37.5 percent) or mixed (61.5 percent) versus venous only (25 percent) etiology (p = 0.06). Failure was more likely the greater number of days postoperatively the take-back occurred (p = 0.02).

Conclusions:

The number of returns to the operating room is inversely proportional to flap salvage. Mechanical and venous etiologies tend to result in salvage and arterial and thrombotic etiologies in failure. Earlier take-backs are more likely to be successful. Knowledge of these predictors of salvage should guide clinical decision making and informed consent.

CLINICAL QUESTION/LEVEL OF EVIDENCE:

Risk, II.
Squamosal Suture Synostosis
Authors: Smartt James M. , Singh Davinder J. , Reid Russell R. , Hellinger Jeffrey C. , Hsu Vivian M. , Bartlett Scott P.
Published: March 2012

Background:

The squamosal suture is markedly different from the major calvarial sutures of the human skull. The unique properties of the suture are a result of the complex developmental biology of the temporal bone and biomechanical force exerted by surrounding structures. The dysmorphic effects of premature fusion of the suture, and possible treatment strategies in cases of synostosis, have received only brief description in the literature.

Methods:

A retrospective case series was performed. The study included patients evaluated by one of the senior authors (S.P.B., R.R.R., and D.J.S.) between 1993 and 2009. All pertinent patient data including inpatient and outpatient charts, photographic records, and radiographic scans were reviewed. Any management performed under the direction of a craniofacial surgeon was documented—including orthotic helmet therapy and operative management.

Results:

The study included 14 patients. Synostosis of the squamosal suture was noted to occur either in an isolated fashion or in the setting of other craniofacial malformations. Patients with isolated squamosal synostosis often suffered from a deformity that was mild in severity and tended to improve with time. However, when occurring in the setting of other forms of craniosynostosis, the deformity was often progressive, and transcranial surgery was frequently required.

Conclusions:

Synostosis of the squamosal suture can result in, or contribute to, significant craniofacial dysmorphism. The optimal form of therapy for this disorder is evolving.
Tip Rhinoplasty in Broad Noses in a Turkish Population
Authors: Erol Ö. Onur
Published: March 2012

Background:

Historically, one of the most persistent challenges to the rhinoplasty surgeon has been the thick, heavy, and poorly defined nasal tip. In the Mediterranean, Anatolian, and Middle Eastern regions, rhinoplasty is the most frequently performed aesthetic procedure. In these regions, the ethnic characteristic of the nasal tip is mostly broad with thick skin, a poorly defined nasal tip, and weak lower lateral cartilages, which makes shaping the tip challenging. In this population, conventional rhinoplasty techniques may result in dissatisfied patients and surgeons.

Methods:

The author presents his experience over the past 20 years with 3800 rhinoplasty patients with broad noses treated using his personal approach.

Results:

Using the Turkish delight type of cartilage graft (diced cartilage wrapped in Surgicel) for the tip region and the columellar strut improved the author's results considerably, giving the tip the desired form and eliminating the complications of late show seen in other types of tip grafts. In patients with very short columellae, insertion of a secondary strut was necessary after 1 year.

Conclusions:

This technique is safe, reliable, effective, simple, and easily applicable by plastic surgeons at all experience levels. Early and late results are very satisfactory, and there is no late show as is sometimes seen with other types of cartilage grafts such as crushed, oval, or rectangular grafts.

CLINICAL QUESTION/LEVEL OF EVIDENCE:

Therapeutic, IV.
Chicks, like children, spontaneously reorient by three-dimensional environmental geometry, not by image matching
Authors: Lee Sang Ah , Spelke Elizabeth S. , Vallortigara Giorgio
Published: March 2012

Spatial reorientation by layout geometry occurs in numerous species, but its underlying mechanisms are debated. While some argue that navigating animals' sense of place is based on geometric computations over three-dimensional representations, others claim it depends on panoramic image-matching processes. Because children reorient by subtle three-dimensional perturbations of the terrain and not by salient two-dimensional brightness contours on surfaces or freestanding columns, children's sense of place cannot be explained by image matching. To test image-matching theories in a different species, the present experiment investigates the reorientation performance of domestic chicks (
Gallus gallus
) in environments similar to those used with children. Chicks, like children, spontaneously reoriented by geometric relationships of subtle three-dimensional terrains, and not by salient two-dimensional brightness contours on surfaces or columns. These findings add to the evidence for homologous navigation systems in humans and other vertebrates, and they cast doubt on image-matching theories of reorientation in these species.
The long and the short of avian W chromosomes: no evidence for gradual W shortening
Authors: Rutkowska Joanna , Lagisz Malgorzata , Nakagawa Shinichi
Published: March 2012

The well-established view of the evolution of sex chromosome dimorphism is of a gradual genetic and morphological degeneration of the hemizygous chromosome. Yet, no large-scale comparative analysis exists to support this view. Here, we analysed karyotypes of 200 bird species to test whether the supposed directional changes occur in bird sex chromosomes. We found no support for the view that W chromosomes gradually become smaller over evolutionary time. On the contrary, the length of the W chromosome can fluctuate over short time scales, probably involving both shortening and elongation of non-coding regions. Recent discoveries of near-identical palindromes and neo-sex chromosomes in birds may also contribute to the observed variation. Further studies are now needed to investigate how chromosome morphology relates to its gene content, and whether the changes in size were driven by selection.
Parasitoids as vectors of facultative bacterial endosymbionts in aphids
Authors: Gehrer Lukas , Vorburger Christoph
Published: March 2012

Heritable bacterial endosymbionts play an important role in aphid ecology. Sequence-based evidence suggests that facultative symbionts such as
Hamiltonella defensa
or
Regiella insecticola
also undergo horizontal transmission. Other than through male-to-female transfer during the sexual generation in autumn, the routes by which this occurs remain largely unknown. Here, we tested if parasitoids or ectoparasitic mites can act as vectors for horizontal transfer of facultative symbionts. Using symbiont-specific primers for diagnostic PCR, we demonstrate for the first time, to our knowledge, that parasitoids can indeed transfer
H. defensa
and
R. insecticola
by sequentially stabbing infected and uninfected individuals of their host,
Aphis fabae
, establishing new, heritable infections. Thus, a natural route of horizontal symbiont transmission is also available during the many clonal generations of the aphid life cycle. No transmissions by ectoparasitic mites were observed, nor did parasitoids that emerged from symbiont-infected aphids transfer any symbionts in our experiments.
Assessing the impact of adherence to anti-retroviral therapy on treatment failure and resistance evolution in HIV
Authors: Cadosch Dominique , Bonhoeffer Sebastian , Kouyos Roger
Published: March 2012

The adherence of patients to therapy is a crucial factor for successful HIV anti-retroviral therapy. Imperfect adherence may lead to treatment failure, which can cause the emergence of resistance within viral populations. We have developed a stochastic model that incorporates compartments of latently infected cells and virus genotypes with different susceptibilities to three simultaneously used drugs. With this model, we study the impact of several key parameters on the probability of treatment failure, i.e. insufficient viral suppression, and the emergence of resistance. Specifically, we consider the impact of drug dosage, drug half-lives, fitness costs for resistance, different basic reproductive numbers of the virus and the influence of pre-existing mutations under various levels of adherence. Furthermore, we also investigate the influence of different temporal distributions of non-adherent days (drug holidays) during a treatment. Factors that promote resistance evolution include a high reproductive number, extended drug holidays and poor adherence. Pre-existing mutations only have a substantial effect if they confer resistance against more than one drug. Overall, our study highlights the importance of the interactions between imperfect adherence, pharmacodynamics, pharmacokinetics and latently infected cells for our understanding of drug resistance and therapy failure in HIV anti-retroviral therapy.
Toner-print removal from paper by long and ultrashort pulsed lasers
Authors: Leal-Ayala David Ricardo , Allwood J. M. , Schmidt M. , Alexeev I.
Published: March 2012

Toner-print removal from paper would allow paper to be re-used instead of being recycled, incinerated or disposed of in landfill. This could significantly reduce the environmental impact of paper production and use. Previous work on the subject has explored the applicability of ultraviolet, visible and infrared (IR) lasers under nanosecond pulses for toner removal. This article expands on this work by testing a wider range of ultrafast and long-pulsed lasers. Results from 10 distinct laser set-ups are used to propose an operating window for the toner-removal process. Colour analysis under the
L
*
a
*
b
* colour space, scanning electron microscope examination and attenuated total reflectance–Fourier transform IR spectroscopy measurements of the outcome show that, with the right laser, it is possible to remove toner from paper to enable its re-use. Theoretical models to predict the laser ablation of toner are discussed, and, while imperfect, provide sufficient evidence to support a physical explanation of toner ablation.
Rational design of single-site heterogeneous catalysts: towards high chemo-, regio- and stereoselectivity
Authors: Dal Santo Vladimiro , Guidotti Matteo , Psaro Rinaldo , Marchese Leonardo , Carniato Fabio , Bisio Chiara
Published: March 2012

The main methods for the design and preparation of single-site heterogeneous catalysts on inorganic oxide supports are described and reviewed. Catalytically active metal sites can be either introduced into the framework of porous materials via direct synthesis or added to a pre-existing support by post-synthesis techniques. Particular attention is paid to selected examples where the geometry, the nature and the chemical surroundings of the active single site is a key factor to obtain catalytic systems with enhanced chemo-, regio- and stereoselectivity. The ever-increasing capabilities of ‘nanoarchitecture’ at molecular level enable chemists to build ideal catalysts for the sustainable transformation of bulky and high added-value molecules.
Hybrid organic–inorganic structured materials as single-site heterogeneous catalysts
Authors: Díaz Urbano , Boronat Mercedes , Corma Avelino
Published: March 2012

Catalyst selectivity is associated with well-defined homogeneous active sites. Transition metal complexes and organocatalysts are highly active and selective in the homogeneous phase, and their heterogenization by incorporating them into inorganic solid materials allows combining their excellent catalytic activity with improved separation, recovering and recycling properties. In this article, we present the structural characteristics and catalytic properties of hybrid organic–inorganic materials in which the molecular catalysts are part of the inorganic structure, emphasizing the possibilities of periodic mesoporous hybrid materials and coordination polymers as single-site solid catalysts.
Chiral porous metal-organic frameworks with dual active sites for sequential asymmetric catalysis
Authors: Song Feijie , Zhang Teng , Wang Cheng , Lin Wenbin
Published: March 2012

Metal-organic frameworks (MOFs) are a class of organic–inorganic hybrid materials built from metal-connecting nodes and organic-bridging ligands. They have received much attention in recent years owing to the ability to tune their properties for potential applications in various areas. Properly designed MOFs with uniform, periodically aligned active sites have shown great promise in catalysing shape-, size-, chemo-, regio- and stereo-selective organic transformations. This study reports the synthesis and characterization of two chiral MOFs (CMOFs
1
and
2
) that are constructed from Mn-salen-derived dicarboxylic acids [salen is (
R
,
R
)-
N
,
N
′-bis(5-
tert
-butylsalicylidene)-1,2-cyclohexanediamine], bis(4-vinylbenzoic acid)-salen manganese(III) chloride (H
2
L
4
) or bis(benzoic acid)-salen manganese(III) chloride (H
2
L
3
) and [Zn
4
(μ
4
-O)(O
2
CR)
6
] or [Zn
5
(H
2
O)
2
(μ
3
-OH)
2
(O
2
CR)
8
] secondary building units (SBUs), respectively. The SBUs in CMOF-
1
are connected by the linear ditopic Mn-salen-derived linkers to construct a fourfold interpenetrated isoreticular MOF (IRMOF) structure with
pcu
topology. In CMOF-
2
, the Mn-salen centres dimerize in a cross-linking way to form a diamondoid structure with threefold interpenetration. CMOF-
1
was examined for highly regio- and stereo-selective tandem alkene epoxidation/epoxide ring-opening reactions by using the Mn-salen andZn
4
(μ
4
-O)(carboxylate)
6
active sites, respectively. Our work demonstrated the potential utility of chiral MOFs with multiple active sites in the efficient synthesis of complex molecules with excellent regio- and stereo-controls
Decreased GH dose after the catch‐up growth period maintains metabolic outcome in short prepubertal children with and without classic GH deficiency
Authors: Decker Ralph , Albertsson‐Wikland Kerstin , Kriström Berit , Halldin Maria , Dahlgren Jovanna
Published: March 2012

Objective

Few studies have evaluated metabolic outcomes following growth hormone (GH) treatment in short prepubertal children during different periods of growth. Previously, we found that individualized GH dosing in the catch‐up period reduced the variation in fasting insulin levels by 34% compared with those receiving a standard GH dose. We hypothesized that the GH dose required to maintain beneficial metabolic effects is lower during the prepubertal growth phase after an earlier catch‐up growth period.

Design

Short prepubertal children with isolated GH deficiency or idiopathic short stature were randomized to individualized GH treatment (range, 17–100 μg/kg/day) or a standard dose in a preceding 2‐year study. After achieving near mid‐parental heightSDS, children receiving an individualized dose were randomized to either a 50% reduced individualized dose (RID, n = 28) or an unchanged individualized dose (UID, n = 37) for 2 years. The dose remained unchanged in 33 children initially randomized to receive a standard dose (FIX, 43 μg/kg/day).We evaluated whether the variations in metabolic parameters measured during maintenance growth diminished in RID compared with UID or FIX.

Results

We observed less variation in fasting insulin levels (−50%), insulin sensitivity as assessed by homoeostasis model assessment (−55·1%), lean soft tissue (−27·8%) and bone mineral content (−31·3%) in RID compared with UID (all P < 0·05), but no differences compared with FIX.

Conclusions

Continued reduced individualized GH treatment after the catch‐up growth period is safe and reduces hyperinsulinism. Individualized GH dose can be reduced once the desired heightSDS is achieved to avoid overtreatment in terms of metabolic outcome.
Controlled source strength variation by changing the firing pressure ‐ a sensitivity study for 4D calibration
Authors: Barker Daniel , Landrø Martin
Published: March 2012

For a 4D seismic operation to be successful, it is important to know what kind of 4D signal we expect to observe, as well as its magnitude. Normally, in a 4D feasibility study, we use rock physics models to quantify the effect of fluid or pressure changes within the reservoir and calculate the corresponding effects to the seismogram. However, to find if the predicted changes are actually observable at a given field, a dedicated calibration procedure might give valuable insight. One such procedure for marine seismics is to gradually change the source strength by varying the firing pressure in order to detect the sensitivity threshold for a given subsurface reflection. This procedure would be practical and feasible if the change of the source signature changes linearly with the source pressure. However, non‐linear effects will lead to minor changes in the later arrivals of the source signature, the so‐called bubble. By investigating these introduced errors for a reasonable air‐gun array we conclude that the method is still feasible since we find it possible to control and diminish the impact of the introduced errors.
Lack of correlation between sealer penetration into dentinal tubules and sealability in nonbonded root fillings
Authors: De‐Deus G. , Brandão M. C. , Leal F. , Reis C. , Souza E. M. , Luna A. S. , Paciornik S. , Fidel S.
Published: March 2012

De‐Deus G, Brandão MC, Leal F, Reis C, Souza EM, Luna AS, Paciornik S, Fidel S. Lack of correlation between sealer penetration into dentinal tubules and sealability in nonbonded root fillings. International Endodontic Journal, 45, 642–651, 2012.

Aim  To determine the correlation between leakage and sealer penetration into dentinal tubule.

Methodology  The root canal of 60 mandibular central incisor teeth were prepared and filled under standardized conditions. Teeth were placed into a device to assess glucose penetration using 15 psi pressure application. After 1 h, glucose concentrations in the lower chamber were measured using an enzymatic reaction. Each specimen was then sectioned horizontally at 3, 6 and 8 mm from the apex, and a standard metallographic preparation was performed. The coronally facing surface of each slice was examined in a high‐resolution stereomicroscope and under Confocal Laser Scanning Microscope. For each slice, the external outline of the root canal, the internal circumference of the root canal walls and the areas along the canal walls where the sealer had penetrated into the dentinal tubules (sealer tags) were outlined and measured. Afterwards, the percentage of the sealer penetration in each section was calculated. The Spearman correlation test was used to verify the correlation between the variables studied (glucose leakage and sealer penetration into dentinal tubules).

Results  The means and standard deviations of glucose leakage were 0.744 g L−1 (±0.5), and the percentage of the dentinal tubule sealer penetration varied between teeth from 5.6% to 42.21%, with an average of 13.7 ± 17.2%. The Spearman correlation test revealed no significant correlation between the two factors analysed (P = 0.082). The r2 value was equal to 0.12.

Conclusions  There was no significant correlation between sealability sealer penetration into dentinal tubles. The lack of correlation reported is of relevance as sealer penetration into dentinal tubules has been used as an advantageous property during the launch of new root filling materials and techniques.