bluuebunny/crossref_metadata_2025 huggingface dataset:
The Evolving Epidemiology of Methicillin-Resistant Staphylococcus aureus at a University Hospital
Authors: Layton Marcelle C. , Hierholzer Walter J. , Patterson Jan Evans
Published: September 2009

Objective:

To describe the epidemiology of methicillin-resistant Staphylococcus aureus (MRSA) at a university hospital during a 14-month period.

Design:

Prospective laboratory-based surveillance for MRSA with descriptive epidemiology based on medical chart review and characterization of strains by DNA typing, using pulsed-field gel electrophoresis (PFGE).

Setting:

An 850-bed tertiary care university hospital.

Patients:

Patients with clinical isolates of MRSA.

Main Outcome Measure:

Determination whether MRSA isolates were community- or hospital-related.

Results:

Among 87 patients with MRSA, 36 (41%) had community-acquired infections. Community acquisition was associated with recent hospitalization, previous antibiotic therapy, nursing home residence, and intravenous drug use. Greater than 3 months had elapsed from the time of discharge for 13 (62%) of the 21 patients with community-acquired isolates hospitalized within the last year. Eight patients (22%) with community-acquired MRSA had no discernible risk factors. PFGE allowed differentiation of 35 distinct whole-cell DNA patterns; heterogeneity was seen among both nosocomial and community-acquired isolates, with few instances of cross-transmission.

Conclusions:

Our data suggest an increase in community acquisition of MRSA. PFGE demonstrated heterogeneity of MRSA isolates from both the community and the hospital setting.
Interrepeat Fingerprinting of Third- Generation Cephalosporin-Resistant Enterobacter cloacae Isolated During an Outbreak in a Neonatal Intensive Care Unit
Authors: Verweij Paul E. , Van Belkum Alex , Melchers Willem J.G. , Voss Andreas , Hoogkamp-Korstanje Jacomina A.A. , Meis Jacques F.G.M.
Published: September 2009

Objective:

To investigate an outbreak in neonates of Enterobacter cloacae infection resistant to third-generation cephalosporins.

Design:

A retrospective study of an outbreak in the neonatal intensive care unit (NICU) and review of E cloacae isolates in pediatric wards and other intensive care units from June 1992 through March 1993.

Setting:

An academic tertiary care hospital.

Patients:

Six patients admitted to the NICU were colonized or infected with E cloacae resistant to third-generation cephalosporins. In the period preceding the outbreak, four E cloacae isolates were available from four patients in the pediatric surgical ward. Nine isolates from four patients in two other intensive care units (ICUs) also were collected during the outbreak. Isolates were biotyped by the API 50CH system and genotyped by polymerase chain reaction (PCR) fingerprinting.

Results:

Typing by interrepeat PCR showed that 21 isolates, which were obtained from five neonates, were identical. One neonate was colonized with a different strain. Some neonates were colonized with a single type of E cloacae for a relatively long period of time. Isolates of patients who were cared for in the pediatric surgical ward and the two other intensive care units (ICUs) showed different genotypes. One patient in an ICU was colonized with an E cloacae strain genetically identical to the outbreak strain. No predominant biotype could be established.

Conclusions:

E cloacae can colonize neonates for a long period of time and although colonization with E cloacae initially may arise endogenously, we were able to show further transmission by cross-contamination in a neonatal intensive care unit.
Recovery of Pseudomonas cepacia and Other Pseudomonas Species from the Environment
Authors: Mortensen Joel E. , Fisher Margaret C. , LiPuma John J.
Published: September 2009

Nine hundred sixteen cultures were obtained from homes of patients with cystic fibrosis, control homes, salad bars, and food markets, and analyzed for the presence of Pseudomonas cepacia and related bacteria. P cepacia was recovered from 5 (18%) of 27 homes, and from 20 (4%) of 509 cultures collected outside of homes. Relative to other pseudomonads, P cepacia is found infrequently in the environment. It is not clear how frequently these sources contribute to acquisition of this bacteria by persons with cystic fibrosis.
The Project to Monitor Indicators: A Collaborative Effort Between the Joint Commission on Accreditation of Healthcare Organizations and the Society for Healthcare Epidemiology of America
Authors: Kritchevsky Stephen B. , Simmons Bryan P. , Braun Barbara I.
Published: September 2009

The Project to Monitor Indicators (PMI) will be a collaborative effort between the Society for Healthcare Epidemiology of America (SHEA) and the Joint Commission on Accreditation of Healthcare Organizations (JCAHO). The goal of this collaboration is to create an intellectual infrastructure to support the effective use, development, understanding, and continuous improvement of clinical quality indicators through coordinated study by hospital epidemiologists.

The Joint Commission is in the midst of an extensive effort to develop a set of indicators that reflect the performance of various aspects of clinical practice. These indicators will form the foundation of a national comparative measurement system called the Indicator Measurement System (IMSystem). It is the Joint Commission's plan that hospitals will be required to participate in the IMSystem as part of the accreditation process in the near future.
The Effect of Surveillance Definitions on Nosocomial Urinary Tract Infection Rates in a Rehabilitation Hospital
Authors: Lewis Steven M.
Published: September 2009

This article presents original research findings to illustrate the influence of surveillance definitions on infection rate. Several definitions for urinary tract infection were applied to clinical and laboratory data from rehabilitation hospital patients, and the effect on sensitivity and specificity examined. We demonstrate that it is essential to take into account the influence of the surveillance definition when interpreting surveillance data, and the importance of ensuring that the surveillance definition is compatible with the surveillance objectives when selecting a definition. Surveillance definitions that serve well in one surveillance program may not serve well in another.
Infection Control in Switzerland
Authors: Pittet Didier , Francioli Patrick , von Overbeck Jan , Raeber Pierre-Alain , Ruef Christian , Widmer Andreas F.
Published: September 2009

Infection control in hospitals is not mandatory in Switzerland as in the United States. There are more than 300 acute-care hospitals in Switzerland. Hospitals are reimbursed by patient-days rather than diagnosis-related group. However, all five Swiss university hospitals have developed an infection control program. The major criteria for setting up and running these programs are reviewed; data are based on a questionnaire and personal interviewing of each institution. Most of the major criteria exist in all five institutions. Resources allocated to infection control differ markedly. The number of infection control nurses per 250 beds varies between 0.2 and 0.75 for the five hospitals; the activity of those in charge of infection control differs between hospitals. A comparison is made between the Swiss and U.S. programs with regard to some aspects of healthcare and infection control.
Containment of Pertussis in the Regional Pediatric Hospital During the Greater Cincinnati Epidemic of 1993
Authors: Christie Celia D.C. , Glover Anne Marie , Willke Mary Jane , Marx Mary L. , Reising Shirley F. , Hutchinson Nancy M.
Published: September 2009

Objective:

To describe methods of preventing nosocomial pertussis in patients, employees, and visitors to a hospital during a communitywide epidemic in Greater Cincinnati.

Design:

Six-month descriptive study of the methods, effectiveness, and cost of a program to prevent nosocomial pertussis.

Setting:

Three hundred sixty-one bed, tertiary-care, university, pediatric hospital.

Results:

We educated 3,764 hospital employees about pertussis. We evaluated 206 employees with respiratory illnesses, based on clinical presentation, pertussis exposure, and work setting. Eighty-seven had pertussis: 84 coughed for ≥2 weeks (outbreak clinical case definition), 65 had paroxysms, 27 whooped, 22 had posttussive emesis, and 13 were positive by direct fluorescent antibody or culture for Bordetella pertussis. Seventy-nine employees were sent on 5-day furloughs. Six hundred twenty-two employees received 14 days of erythromycin (579) or trimethoprim-sulfamethoxazole (43). Symptomatic patients were identified at triage in the emergency department and placed in respiratory isolation. Suspect pertussis cases were admitted in respiratory isolation. Among 49 toddlers who were given erythromycin and managed in “coughing respiratory cohorts,” eight had proven pertussis. Inpatients were restricted to assigned nursing units. Respiratory masks were required for those entering the test referral center, where more than 3,500 pertussis cultures were performed. Hospitalwide visitor restriction was enforced for those aged 14 years or younger and for those with respiratory symptoms. Only parents and guardians were permitted to visit the newborn intensive care unit. A child-care service managed 488 inpatient sibling visitors. Four symptomatic children in the employees' child-care center were excluded pending physician evaluation; one had pertussis.

Conclusions:

Control measures appeared effective. Pertussis occurred in 87 (2%) employees. Among 102 children hospitalized with pertussis, respiratory isolation was delayed in nine cases, and one case was nosocomial. Program expenses totalled $85,400. Adult booster immunization with acellular pertussis vaccine might represent the safest and least expensive strategy for preventing epidemic pertussis, and controlled trials of acellular pertussis vaccine in hospital employees are needed.
Vertical Transmission of Citrobacter diversus Documented by DNA Fingerprinting
Authors: Harvey Brenda S. , Koeuth Thearith , Versalovic James , Woods Charles R. , Lupski James R.
Published: September 2009

Objective:

To confirm the vertical transmission of Citrobacter diversus from a mother to her infant and to evaluate the epidemiologic usefulness of a new automated procedure for analysis of polymerase chain reaction (PCR)-generated DNA fingerprints.

Design:

Repetitive element-based PCR (rep-PCR) analysis of C diversus isolates from the blood and amniotic fluid of a mother and the blood of her infant was performed. Unrelated C diversus isolates also were characterized and compared with the isolates from mother and infant. DNA fingerprints were generated by gel electrophoresis of PCR products derived from either unlabeled standard repetitive sequence-based oligonucleotide primers or fluorescent primers. The standard rep-PCR fingerprints were analyzed by visual inspection. The fluorescent primers were used in fluorophore-enhanced rep-PCR (FERP), and the FERP DNA fingerprints were analyzed by an Applied BioSystems (ABI) Model 373A laser scanning unit equipped with Genescan 672 software (Applied Biosystems, Inc, Foster City, CA).

Setting and Patients:

A mother and her newborn infant, both with invasive disease due to C diversus, in an urban tertiary-care hospital.

Results:

The DNA fingerprints of the maternal blood, amniotic fluid, and infant blood isolates of C diversus were identical by both visual inspection of ethidium bromide-stained agarose gels and computer-aided analysis of FERP patterns. These strains appeared to differ from all but one control isolate, which had been collected 7 years earlier in the same city in which the infant was born.

Conclusions:

Vertical transmission of C diversus from mother to infant can occur in utero. Automated analysis of rep-PCR–generated DNA fingerprints derived using fluorescent primers is an objective means for comparing isolates of C diversus and in all likelihood would be useful for other species of bacteria that possess repetitive elements.
Treatment of Hickman Catheter Sepsis Using Antibiotic Lock Technique
Authors: Krzywda Elizabeth A. , Andris Deborah A. , Edmiston Charles E. , Quebbeman Edward J.
Published: September 2009

Antibiotic lock therapy, an alternative treatment for Hickman catheter sepsis, was evaluated in six recipients of prolonged outpatient intravenous therapy. Twenty-two episodes of catheter sepsis were identified, involving coagulase-negative staphylococci (11), gram-negative bacilli (3), gram-positive bacilli (1), yeast (4), and mixed bacteria or fungi (3). In a select group of patients, treatment was successful 92% of the time.
Hospital Epidemiology in Smaller Hospitals
Authors: Boyce John M.
Published: September 2009

In hospitals with 200 to 300 beds, hospital epidemiologists serve primarily as medical and epidemiology consultants to the infection control practitioners, as advocates for the infection control programs, and as chairpersons of the infection control committees. Because smaller hospitals often have limited resources for infection control, surveillance and control activities must focus on issues that have caused problems for the facility and on compliance with mandates and recommendations made by healthcare agencies. The clinical microbiology laboratory plays an important role in ongoing surveillance activities and often is responsible for performing cultures obtained during point prevalence culture surveys or outbreak investigations. Because laboratory support often is limited, the indications for obtaining a culture from patients, personnel, or the inanimate environment for infection control purposes must be reviewed and discussed carefully with the clinical laboratory in advance.
Nilpotent orbits in classical Lie algebras over finite fields of characteristic 2 and the Springer correspondence
Authors: Xue Ting
Published: September 2009

Let

G
G

be an adjoint algebraic group of type

B
B

,

C
C

, or

D
D

over an algebraically closed field of characteristic 2. We construct a Springer correspondence for the Lie algebra of

G
G

. In particular, for orthogonal Lie algebras in characteristic 2, the structure of component groups of nilpotent centralizers is determined and the number of nilpotent orbits over finite fields is obtained.
The Transforming Growth Factor-β Type III Receptor Mediates Distinct Subcellular Trafficking and Downstream Signaling of Activin-like Kinase (ALK)3 and ALK6 Receptors
Authors: Lee Nam Y. , Kirkbride Kellye C. , Sheu Richard D. , Blobe Gerard C.
Published: September 2009

Bone morphogenetic proteins (BMPs) signal through the BMP type I and type II receptors to regulate cellular processes, including embryonic development. The type I BMP receptors activin-like kinase (ALK)3 and ALK6 share a high degree of homology, yet possess distinct signaling roles. Here, we report that although the transforming growth factor (TGF)-β type III receptor (TβRIII) enhanced both ALK3 and ALK6 signaling, TβRIII more potently enhanced ALK6-mediated stimulation of the BMP-responsive promoters XVent2 and 3GC2, and up-regulation of the early response gene Smad6. In contrast, TβRIII specifically enhanced ALK3-mediated up-regulation of the early response gene ID-1. TβRIII associated with ALK3 primarily through their extracellular domains, whereas its interaction with ALK6 required both the extracellular and cytoplasmic domains. TβRIII, along with its interacting scaffolding protein β-arrestin2, induced the internalization of ALK6. In contrast, TβRIII colocalized with and resulted in the cell surface retention of ALK3, independently of β-arrestin2. Although complex formation between TβRIII, ALK6, and β-arrestin2 and TβRIII/ALK6 internalization resulted in maximal BMP signaling, the TβRIII mutant unable to interact with β-arrestin2, TβRIII-T841A, was unable to do so. These studies support a novel role for TβRIII in mediating differential ALK3 and ALK6 subcellular trafficking resulting in distinct signaling downstream of ALK3 and ALK6.
Integrating population genetics and conservation biology in the era of genomics
Authors: Ouborg N. Joop
Published: September 2009

As one of the final activities of the ESF-CONGEN Networking programme, a conference entitled ‘Integrating Population Genetics and Conservation Biology’ was held at Trondheim, Norway, from 23 to 26 May 2009. Conference speakers and poster presenters gave a display of the state-of-the-art developments in the field of conservation genetics. Over the five-year running period of the successful ESF-CONGEN Networking programme, much progress has been made in theoretical approaches, basic research on inbreeding depression and other genetic processes associated with habitat fragmentation and conservation issues, and with applying principles of conservation genetics in the conservation of many species. Future perspectives were also discussed in the conference, and it was concluded that conservation genetics is evolving into conservation genomics, while at the same time basic and applied research on threatened species and populations from a population genetic point of view continues to be emphasized.
Affective responses in tamarins elicited by species-specific music
Authors: Snowdon Charles T. , Teie David
Published: September 2009

Theories of music evolution agree that human music has an affective influence on listeners. Tests of non-humans provided little evidence of preferences for human music. However, prosodic features of speech (‘motherese’) influence affective behaviour of non-verbal infants as well as domestic animals, suggesting that features of music can influence the behaviour of non-human species. We incorporated acoustical characteristics of tamarin affiliation vocalizations and tamarin threat vocalizations into corresponding pieces of music. We compared music composed for tamarins with that composed for humans. Tamarins were generally indifferent to playbacks of human music, but responded with increased arousal to tamarin threat vocalization based music, and with decreased activity and increased calm behaviour to tamarin affective vocalization based music. Affective components in human music may have evolutionary origins in the structure of calls of non-human animals. In addition, animal signals may have evolved to manage the behaviour of listeners by influencing their affective state.
Nanoparticles, human health hazard and regulation
Authors: Seaton Anthony , Tran Lang , Aitken Robert , Donaldson Kenneth
Published: September 2009

New developments in technology usually entail some hazard as well as advantage to a society. Hazard of a material translates into risk by exposure of humans and/or their environment to the agent in question, and risk is reduced by control of exposure, usually guided by regulation based on understanding of the mechanisms of harm. We illustrate risks relating to the causation of diseases associated with exposure to aerosols of combustion particles and asbestos, leading to paradigms of particle toxicity, and discuss analogies with potential exposure to manufactured nanoparticles (NPs). We review the current understanding of the hazard of NPs derived from the new science of nanotoxicology and the limited research to date into human exposure to these particles. We identify gaps in knowledge relating to the properties of NPs that might determine toxicity and in understanding the most appropriate ways both to measure this in the laboratory and to assess it in the workplace. Nevertheless, we point out that physical principles governing the behaviour of such particles allow determination of practical methods of protecting those potentially exposed. Finally, we discuss the early steps towards regulation and the difficulties facing regulators in controlling potentially harmful exposures in the absence of sufficient scientific evidence.
Pressure rise generated by the expansion of a local gas volume in a closed vessel
Authors: Stamps Douglas , Cooper Edward , Egbert Ryan , Heerdink Steve , Stringer Valerie
Published: September 2009

Experiments were conducted to determine the pressure rise that results from either the combustion of a localized gas volume or the expansion of a pressurized gas volume adjacent to an inert gas in a closed vessel. The experiments consisted of either pressurized air or the combustion of stoichiometric and fuel-lean hydrogen–air mixtures compressing an inert gas. The pressure rise in the inert gas was measured as a function of either the volume fraction or the initial pressure of the expanding gas. Helium, nitrogen, air and carbon dioxide were tested to explore the effect of inert gas heat capacity on the pressure rise. The final pressure of the inert gas increased with the volume fraction and initial pressure of the expanding gas, and was influenced to a lesser extent by the heat capacity of the inert gas. A model was assessed using the experimental data, and the theoretical results were consistent with the observed trends. This model and other published models were assessed and compared using prior data for localized gas combustion surrounded by an inert gas and the partial combustion of homogeneous methane–air mixtures.
Deterioration, death and the evolution of reproductive restraint in late life
Authors: McNamara John M. , Houston Alasdair I. , Barta Zoltan , Scheuerlein Alexander , Fromhage Lutz
Published: September 2009

Explaining why organisms schedule reproduction over their lifetimes in the various ways that they do is an enduring challenge in biology. An influential theoretical prediction states that organisms should increasingly invest in reproduction as they approach the end of their life. An apparent mismatch of empirical data with this prediction has been attributed to age-related constraints on the ability to reproduce. Here we present a general framework for the evolution of age-related reproductive trajectories. Instead of characterizing an organism by its age, we characterize it by its physiological condition. We develop a common currency that if maximized at each time guarantees the whole life history is optimal. This currency integrates reproduction, mortality and changes in condition. We predict that under broad conditions it will be optimal for organisms to invest less in reproduction as they age, thus challenging traditional interpretations of age-related traits and renewing debate about the extent to which observed life histories are shaped by constraint versus adaptation. Our analysis gives a striking illustration of the differences between an age-based and a condition-based approach to life-history theory. It also provides a unified account of not only standard life-history models but of related models involving the allocation of limited resources.
A new mammal skull from the Lower Cretaceous of China with implications for the evolution of obtuse-angled molars and ‘amphilestid’ eutriconodonts
Authors: Gao Chun-Ling , Wilson Gregory P. , Luo Zhe-Xi , Maga A. Murat , Meng Qingjin , Wang Xuri
Published: September 2009

We report the discovery of
Juchilestes liaoningensis
, a new genus and species of eutriconodont mammal from the Lujiatun Site of the Lower Cretaceous Yixian Formation (123.2 ± 1.0 Ma; Lower Aptian). The holotype preserves a partial skull and full dentition. Among eutriconodonts, its lower dentition is similar to taxa formerly assigned to the paraphyletic group of ‘amphilestids’. Some have considered ‘amphilestid’ molars to represent the structural intermediate between the lower molars of the ‘triconodont’ pattern of cusps in alignment and the fully triangulate and more derived therian molars. However, ‘amphilestid’ taxa were previously represented only by the lower dentition. Our study reveals, for the first time, the upper dentition and skull structure of an ‘amphilestid’, and shows that at least some eutriconodonts have an obtuse-angled cusp pattern on molars in middle positions of the long molar series. Its petrosal is similar to those of other eutriconodonts and spalacotheroid ‘symmetrodonts’. Our phylogenetic analyses suggest that (i)
Juchilestes
is most closely related to the Early Cretaceous
Hakusanodon
from Japan, in the same Eastern Asiatic geographic region; (ii) ‘amphilestids’ are not monophyletic; and (iii) eutriconodonts might not be a monophyletic group, although this hypothesis must be further tested.
Phospholamban S-nitrosylation modulates Starling response in fish heart
Authors: Garofalo F. , Parisella M. L. , Amelio D. , Tota B. , Imbrogno S.
Published: September 2009

The Frank–Starling mechanism is a fundamental property of the vertebrate heart, which allows the myocardium to respond to increased filling pressure with a more vigorous contraction of its lengthened fibres. In mammals, myocardial stretch increases cardiac nitric oxide (NO) release from both vascular endothelium and cardiomyocytes. This facilitates myocardial relaxation and ventricular diastolic distensibility, thus influencing the Frank–Starling mechanism.

In thein vitroworking heart of the eelAnguilla anguilla, we previously showed that an endogenous NO release affects the Frank–Starling response making the heart more sensitive to preload. Using the same bioassay, we now demonstrate that this effect is confirmed in the presence of the exogenous NO donorS-nitroso-N-acetyl penicillamine, is independent from endocardial endothelium and guanylate cyclase/cGMP/protein kinase G and cAMP/protein kinase A pathways, involves a PI(3)kinase-mediated activation of endothelial NO synthase and a modulation of the SR-CA2+ATPase (SERCA2a) pumps. Furthermore, we show that NO influences cardiac response to preload through S-nitrosylation of phospholamban and consequent activation of SERCA2a. This suggests that in the fish heart NO modulates the Frank–Starling response through a beat-to-beat regulation of calcium reuptake and thus of myocardial relaxation.

We propose that this mechanism represents an important evolutionary step for the stretch-induced intrinsic regulation of the vertebrate heart, providing, at the same time, a stimulus for mammalian-oriented studies.
A neurochemical approach to valuation sensitivity over gains and losses
Authors: Zhong Songfa , Israel Salomon , Xue Hong , Sham Pak C. , Ebstein Richard P. , Chew Soo Hong
Published: September 2009

Prospect theory proposes the hypothesis that people have diminishing sensitivity in valuing increases in the size of monetary outcomes, for both gains and losses. For decision-making under risk, this implies a tendency to be risk-tolerant over losses while being generally risk averse over gains. We offer a neurochemistry-based model of the diminishing valuation sensitivity hypothesis. Specifically, we propose that dopamine tone modulates the sensitivity towards valuation of gains while serotonin tone modulates the sensitivity towards valuation of losses. Consequently, higher dopamine tone would yield a more concave valuation function over gains while higher serotonin tone would yield a more convex valuation function over losses. Using a neurogenetics strategy to test our neurochemical model, we find that subjects with the 9-repeat allele of DAT1 (lower DA tone) are more risk-tolerant over gains than subjects with the 10-repeat allele, and that subjects with the 10-repeat allele of STin2 (higher 5HT tone) are more risk-tolerant over losses than subjects with the 12-repeat allele. Overall, our results support the implications of our model and provide the first neurogenetics evidence that risk attitudes are partially hard-wired in differentiating between gain- and loss-oriented risks.
Parallel evolution and ecological selection: replicated character displacement in spadefoot toads
Authors: Rice Amber M. , Leichty Aaron R. , Pfennig David W.
Published: September 2009

Ecological character displacement—trait evolution stemming from selection to lessen resource competition between species—is most often inferred from a pattern in which species differ in resource-use traits in sympatry but not in allopatry, and in which sympatric populations within each species differ from conspecific allopatric populations. Yet, without information on population history, the presence of a divergent phenotype in multiple sympatric populations does not necessarily imply that there has been repeated evolution of character displacement. Instead, such a pattern may arise if there has been character displacement in a single ancestral population, followed by gene flow carrying the divergent phenotype into multiple, derived, sympatric populations. Here, we evaluate the likelihood of such historical events versus ongoing ecological selection in generating divergence in trophic morphology between multiple populations of spadefoot toad (Spea multiplicata) tadpoles that are in sympatry with a heterospecific and those that are in allopatry. We present both phylogenetic and population genetic evidence indicating that the same divergent trait, which minimizes resource competition with the heterospecific, has arisen independently in multiple sympatric populations. These data, therefore, provide strong indirect support for competition's role in divergent trait evolution.
Laterality enhances cognition in Australian parrots
Authors: Magat Maria , Brown Culum
Published: September 2009

Cerebral lateralization refers to the division of information processing in either hemisphere of the brain and is a ubiquitous trait among vertebrates and invertebrates. Given its widespread occurrence, it is likely that cerebral lateralization confers a fitness advantage. It has been hypothesized that this advantage takes the form of enhanced cognitive function, potentially via a dual processing mechanism whereby each hemisphere can be used to process specific types of information without contralateral interference. Here, we examined the influence of lateralization on problem solving by Australian parrots. The first task, a pebble-seed discrimination test, was designed for small parrot species that feed predominately on small seeds, which do not require any significant manipulation with the foot prior to ingestion. The second task, a string-pull problem, was designed for larger bodied species that regularly use their feet to manipulate food objects. In both cases, strongly lateralized individuals (those showing significant foot and eye biases) outperformed less strongly lateralized individuals, and this relationship was substantially stronger in the more demanding task. These results suggest that cerebral lateralization is a ubiquitous trait among Australian parrots and conveys a significant foraging advantage. Our results provide strong support for the enhanced cognitive function hypothesis.
Recent de novo origin of human protein-coding genes
Authors: Knowles David G. , McLysaght Aoife
Published: September 2009

The origin of new genes is extremely important to evolutionary innovation. Most new genes arise from existing genes through duplication or recombination. The origin of new genes from noncoding DNA is extremely rare, and very few eukaryotic examples are known. We present evidence for the de novo origin of at least three human protein-coding genes since the divergence with chimp. Each of these genes has no protein-coding homologs in any other genome, but is supported by evidence from expression and, importantly, proteomics data. The absence of these genes in chimp and macaque cannot be explained by sequencing gaps or annotation error. High-quality sequence data indicate that these loci are noncoding DNA in other primates. Furthermore, chimp, gorilla, gibbon, and macaque share the same disabling sequence difference, supporting the inference that the ancestral sequence was noncoding over the alternative possibility of parallel gene inactivation in multiple primate lineages. The genes are not well characterized, but interestingly, one of them was first identified as an up-regulated gene in chronic lymphocytic leukemia. This is the first evidence for entirely novel human-specific protein-coding genes originating from ancestrally noncoding sequences. We estimate that 0.075% of human genes may have originated through this mechanism leading to a total expectation of 18 such cases in a genome of 24,000 protein-coding genes.
Dual Roles of Reactive Oxygen Species and NADPH Oxidase RBOHD in an Arabidopsis-Alternaria Pathosystem
Authors: Pogány Miklós , von Rad Uta , Grün Sebastian , Dongó Anita , Pintye Alexandra , Simoneau Philippe , Bahnweg Günther , Kiss Levente , Barna Balázs , Durner Jörg
Published: September 2009

Arabidopsis (Arabidopsis thaliana) NADPH oxidases have been reported to suppress the spread of pathogen- and salicylic acid-induced cell death. Here, we present dual roles of RBOHD (for respiratory burst oxidase homolog D) in an Arabidopsis-Alternaria pathosystem, suggesting either initiation or prevention of cell death dependent on the distance from pathogen attack. Our data demonstrate that a rbohD knockout mutant exhibits increased spread of cell death at the macroscopic level upon inoculation with the fungus Alternaria brassicicola. However, the cellular patterns of reactive oxygen species accumulation and cell death are fundamentally different in the AtrbohD mutant compared with the wild type. Functional RBOHD causes marked extracellular hydrogen peroxide accumulation as well as cell death in distinct, single cells of A. brassicicola-infected wild-type plants. This single cell response is missing in the AtrbohD mutant, where infection triggers spreading-type necrosis preceded by less distinct chloroplastic hydrogen peroxide accumulation in large clusters of cells. While the salicylic acid analog benzothiadiazole induces the action of RBOHD and the development of cell death in infected tissues, the ethylene inhibitor aminoethoxyvinylglycine inhibits cell death, indicating that both salicylic acid and ethylene positively regulate RBOHD and cell death. Moreover, A. brassicicola-infected AtrbohD plants hyperaccumulate ethylene and free salicylic acid compared with the wild type, suggesting negative feedback regulation of salicylic acid and ethylene by RBOHD. We propose that functional RBOHD triggers death in cells that are damaged by fungal infection but simultaneously inhibits death in neighboring cells through the suppression of free salicylic acid and ethylene levels.
SET DOMAIN GROUP25Encodes a Histone Methyltransferase and Is Involved inFLOWERING LOCUS CActivation and Repression of Flowering
Authors: Berr Alexandre , Xu Lin , Gao Juan , Cognat Valérie , Steinmetz Andre , Dong Aiwu , Shen Wen-Hui
Published: September 2009

Covalent modifications of histone lysine residues by methylation play key roles in the regulation of chromatin structure and function. In contrast to H3K9 and H3K27 methylations that mark repressive states of transcription and are absent in some lower eukaryotes, H3K4 and H3K36 methylations are considered as active marks of transcription and are highly conserved in all eukaryotes from yeast (Saccharomyces cerevisiae) to Homo sapiens. Paradoxically, protein complexes catalyzing H3K4 and H3K36 methylations are less-extensively characterized in higher eukaryotes, particularly in plants. Arabidopsis (Arabidopsis thaliana) contains 12 SET DOMAIN GROUP (SDG) proteins phylogenetic classified to Trithorax Group (TrxG) and thus potentially involved in H3K4 and H3K36 methylations. So far only some genes of this family had been functionally characterized. Here we report on the genetic and molecular characterization of SDG25, a previously uncharacterized member of the Arabidopsis TrxG family. We show that the loss-of-function mutant sdg25-1 has an early flowering phenotype associated with suppression of FLOWERING LOCUS C (FLC) expression. Recombinant SDG25 proteins could methylate histone H3 from oligonucleosomes and mutant sdg25-1 plants showed weakly reduced levels of H3K36 dimethylation at FLC chromatin. Interestingly, sdg25-1 transcriptome shared a highly significant number of differentially expressed genes with that of sdg26-1, a previously characterized mutant exhibiting late-flowering phenotype and elevated FLC expression. Taken together, our results provide, to our knowledge, the first demonstration for a biological function of SDG25 and reveal additional layers of complexity of overlap and nonoverlap functions of the TrxG family genes in Arabidopsis.
TheSPOROCYTELESS/NOZZLEGene Is Involved in Controlling Stamen Identity in Arabidopsis
Authors: Liu Xiaodong , Huang Jian , Parameswaran Sriram , Ito Toshiro , Seubert Brandon , Auer Max , Rymaszewski Amy , Jia Gengxiang , Owen Heather A. , Zhao Dazhong
Published: September 2009

The stamen, which consists of an anther and a filament, is the male reproductive organ in a flower. The specification of stamen identity in Arabidopsis (Arabidopsis thaliana) is controlled by a combination of the B genes APETALA3 (AP3) and PISTILLATA, the C gene AGAMOUS (AG), and the E genes SEPALLATA1 (SEP1) to SEP4. The “floral organ-building” gene SPOROCYTELESS/NOZZLE (SPL/NZZ) plays a central role in regulating anther cell differentiation. However, much less is known about how “floral organ identity” and floral organ-building genes interact to control floral organ development. In this study, we report that ectopic expression of SPL/NZZ not only affects flower development in the wild-type background but also leads to the transformation of petal-like organs into stamen-like organs in flowers of ap2-1, a weak ap2 mutant allele. Moreover, our loss-of-function analysis indicates that the spl/nzz mutant enhances the phenotype of the ag weak allele ag-4. Furthermore, ectopic expression and overexpression of SPL/NZZ altered expression of AG, SEP3, and AP2 in rosette leaves and flowers, while ectopic expression of SPL/NZZ resulted in ectopic expression of AG and SEP3 in the outer whorls of flowers. Our results indicate that the SPL/NZZ gene is engaged in controlling stamen identity via interacting with genes required for stamen identity in Arabidopsis.
Coordination of Plastid Protein Import and Nuclear Gene Expression by Plastid-to-Nucleus Retrograde Signaling
Authors: Kakizaki Tomohiro , Matsumura Hideo , Nakayama Katsuhiro , Che Fang-Sik , Terauchi Ryohei , Inaba Takehito
Published: September 2009

Expression of nuclear-encoded plastid proteins and import of those proteins into plastids are indispensable for plastid biogenesis. One possible cellular mechanism that coordinates these two essential processes is retrograde signaling from plastids to the nucleus. However, the molecular details of how this signaling occurs remain elusive. Using the plastid protein import2 mutant of Arabidopsis (Arabidopsis thaliana), which lacks the atToc159 protein import receptor, we demonstrate that the expression of photosynthesis-related nuclear genes is tightly coordinated with their import into plastids. Down-regulation of photosynthesis-related nuclear genes is also observed in mutants lacking other components of the plastid protein import apparatus. Genetic studies indicate that the coordination of plastid protein import and nuclear gene expression is independent of proposed plastid signaling pathways such as the accumulation of Mg-protoporphyrin IX and the activity of ABA INSENSITIVE4 (ABI4). Instead, it may involve GUN1 and the transcription factor AtGLK. The expression level of AtGLK1 is tightly correlated with the expression of photosynthesis-related nuclear genes in mutants defective in plastid protein import. Furthermore, the activity of GUN1 appears to down-regulate the expression of AtGLK1 when plastids are dysfunctional. Based on these data, we suggest that defects in plastid protein import generate a signal that represses photosynthesis-related nuclear genes through repression of AtGLK1 expression but not through activation of ABI4.
Insulin‐independent promotion of chemically induced hepatocellular tumor development in genetically diabetic mice
Authors: Yamasaki Kohtaro , Hayashi Yoshihiro , Okamoto Sumika , Osanai Makoto , Lee Gang‐Hong
Published: September 2009

Diabetes mellitus has been proposed as an epidemiological risk factor for human liver cancer development. One reasonable possibility is that this is attributable to hyperinsulinemia compensatory for obesity‐related insulin resistance. However, diabetes mellitus is a complex disease with multiple abnormal conditions essentially caused by hyperglycemia. Therefore, it is not evident whether hyperinsulinemia is prerequisite for the elevated cancer risk. To gain a clue to answer this question, we characterized chemically induced hepatocarcinogenesis in diabetic model mice genetically deficient for insulin. Akita inbred mice originating from the C57BL/6 strain carry a heterozygous germline mutation of the insulin II gene and suffer from inherited insulin deficiency and diabetes in an autosomal dominant manner. They were mated with normal C3H/HeJ mice with high sensitivity to liver carcinogenesis and the resultant F1 littermates, which were either normal or insulin deficient, were exposed to diethylnitrosamine and induced hepatocellular tumors were evaluated for number, size, proliferative activity, and apoptosis. Unexpectedly, both mean and total volumes of hepatocellular tumors in the insulin‐deficient animals were more than twofold larger than those in the normal controls, with no significant difference in tumor number. The tumors in insulin‐deficient mice showed a significantly lower frequency of apoptosis but no alteration in cell proliferation. In conclusion, our results indicate that insulin‐independent liver tumor promotion occurred in diabetic mice. Clearly, insulin‐independent mechanisms for the human case also deserve consideration. (Cancer Sci 2009)
Timing of initiation of enzyme replacement therapy after diagnosis of type 1 Gaucher disease: effect on incidence of avascular necrosis
Authors: Mistry Pramod K. , Deegan Patrick , Vellodi Ashok , Cole J. Alexander , Yeh Michael , Weinreb Neal J.
Published: September 2009

Data from the International Collaborative Gaucher Group Gaucher Registry were analysed to assess the relationship between enzyme replacement therapy with imiglucerase (ERT) and incidence of avascular necrosis (AVN) in type 1 Gaucher disease (GD1), and to determine whether the time interval between diagnosis and initiation of ERT influences the incidence rate of AVN. All patients with GD1 enrolled in the Gaucher Registry who received ERT and did not report AVN prior to starting therapy (n = 2700) were included. The incidence rate of AVN following initiation of ERT was determined. An incidence rate of AVN of 13·8 per 1000 person‐years was observed in patients receiving ERT. Patients who initiated ERT within 2 years of diagnosis had an incidence rate of 8·1 per 1000 person‐years; patients who started ERT ≥2 years after diagnosis had an incidence rate of 16·6 per 1000 person‐years. The adjusted incidence rate ratio was 0·59 [95% confidence interval (CI) 0·36–0·96, P = 0·0343]. Splenectomy was an independent risk factor for AVN (adjusted incidence rate ratio 2·23, 95% CI 1·61–3·08, P < 0·0001). In conclusion, the risk of AVN was reduced among patients who initiated ERT within 2 years of diagnosis, compared to initiating treatment ≥2 years after diagnosis. A higher risk of AVN was observed among patients who had previously undergone splenectomy.
Postoperative impact of daily life after primary treatment of proximal/distal tibiafracture with Ilizarov external fixation
Authors: Modin Marina , Ramos Telmo , Stomberg Margareta Warrén
Published: September 2009

Aims and objectives.  To describe patients’ experience of the impact of their health‐related life situation on their daily life two and four weeks after primary fracture treatment with Ilizarov external fixation.

Background.  A few studies have been conducted postoperatively focussing on fracture treatment with Ilizarov fixation.

Design.  A prospective descriptive research design.

Method.  Patients who had been treated for a proximal/distal tibial fracture were invited to participate in the study. Data were collected with a semi‐structured questionnaire where 20 patients described in their own words their situation at home two and four weeks postoperatively. The process used when analysing the data was similar to content analysis.

Results.  Four key themes were identified: ‘limitations in the home environment’, ‘limitations outside the home’, ‘limitations to social relations’ and ‘experience of having an Ilizarov fixation’. The patient’s life situation was strongly affected during the first postoperative month. This took the form of clear limitations on activities outside the home and a degree of limitation on coping with household chores and personal hygiene. These limitations became less severe after between 2–4 weeks and were very much a consequence of using crutches.

Conclusion.  This study points to limitations in the patient’s daily life situation in the home. The results from the study make it obvious that the information given to patients prior to discharge, concerning the value of putting weight on the leg, had not been clear or that the patients had not understood it. This had a negative impact on the patient’s daily life after discharge. Further data are needed to uncover the extent of the issue to be able to optimise patient outcomes.

Relevance to clinical practice.  There is a need for clearer and more active information from the nurse before discharge but also a need to follow up how the information given is understood.
The identification of older nursing home residents vulnerable for deterioration of grade 1 pressure ulcers
Authors: Vanderwee Katrien , Grypdonck Maria , Bacquer Dirk De , Defloor Tom
Published: September 2009

Aims and objective.  The objective of this study was to identify prognostic factors associated with the development of pressure ulcer lesions (grade 2–4) in nursing home patients with non‐blanchable erythema.

Background.  No studies could be found that identify risk factors for further development of pressure ulcer in patients with non‐blanchable erythema. For some patients with non‐blanchable erythema, standard preventive measures do not suffice to prevent pressure ulcers from deterioration. Identifying these patients beforehand can considerably contribute to the efficiency of pressure ulcer prevention.

Design.  Secondary data analyses of a previously conducted randomised controlled trial were performed.

Methods.  Eighty‐four wards of 16 Belgian nursing homes participated in the study. In total, 235 nursing home residents with a grade 1 pressure ulcer (non‐blanchable erythema) were included. All the residents received standard preventive care. Potential prognostic factors were collected using a standardised form. The incidence of pressure ulcers was recorded according to the European pressure ulcer classification system.

Results.  The cumulative pressure ulcer incidence was 18·7% (44/235). Hypotension (relative risk = 3·42, 95% CI = 1·56–7·49), a history of a cerebral vascular accident (relative risk = 1·94, 95% CI = 1·10–3·70) and contractures (relative risk = 2·02, 95% CI 1·03–3·95) were identified as independent predictive factors for developing pressure ulcers. Remarkably, being urinary incontinent decreased the risk of developing a pressure ulcer by 76%.

Conclusions.  In nursing home residents with non‐blanchable erythema, hypotension, contractures, and a history of cerebral vascular accident were independent risk factors for the development of pressure ulcer lesions.

Relevance to clinical practice.  Patients with non‐blanchable erythema who have hypotension, contractures or a history of cerebral vascular accident are in need of more intensive preventive measures. Identifying these patients can contribute considerably to a more efficient pressure ulcer prevention policy, resulting in a lower pressure ulcer lesion incidence and in lower costs.