bluuebunny/crossref_metadata_2025 huggingface dataset:
Combining the Taguchi Method with an Artificial Neural Network to Construct a Prediction Model for Near-Field Photolithography Experiments
Authors: Lin Z-C , Yang C-B
Published: April 2010

For analysis using the Taguchi method, the L18 or L27 orthogonal array is usually adopted. However, this requires many experiments (18 or 27 runs, respectively), which consumes time and increases costs. In addition, while traditional analysis with the Taguchi model provides a better group of processing parameters, it cannot predict the unexperimented results. This article proposes a progressive Taguchi neural network model that combines the Taguchi method with an artificial neural network and constructs a prediction model for near-field photolithography experiments. This approach establishes a Taguchi neural network that requires fewer experimental runs, while achieving a high predictive precision. The analytical results of the progressive Taguchi neural network model show that, because there are few training examples in the stage 1 preliminary network, there is a significant fluctuation in the network prediction values. In the stage 2 refining network, the prediction effect in the region around the Taguchi factor level points is not bad, but the prediction in the region more remote from the learning and training examples has greater error. The stage 3 precise network can provide optimal prediction results for the full field.
An Enhanced Binary Particle Swarm Optimization for Structural Topology Optimization
Authors: Tseng K-Y , Zhang C-B , Wu C-Y
Published: April 2010

Particle swarm optimization (PSO), a heuristic optimization method, has been successfully applied in solving many optimization problems in real-value search space. The original binary particle swarm optimization (BPSO) uses the concept of bit flipping of the binary string to convert the velocity from a real code into a binary code. However, the conversion process cannot be reversed, and it is difficult to extend this framework to solve certain discrete optimization problems. An enhanced binary particle swarm algorithm is proposed in this study based on pure binary bit-string frameworks to deal with structural topology optimization problems. Further, two enhancement strategies, stress-based strategy and pair-switched strategy, were developed to improve the performance of the proposed algorithm for topology optimization of structure. The results of experimental cases demonstrated in this study show that the proposed enhanced binary particle swarm optimization (EBPSO) with two developed strategies is an efficient population-based approach for finding the optimal design for structural topology optimization problems of minimum compliance design and minimum weight design.
Primary and long-term stability of a short-stem hip implant
Authors: Dabirrahmani D , Hogg M , Kohan L , Gillies M
Published: April 2010

The new generation short-stem hip implants are designed to encourage physiological-like loading, to minimize stress—strain shielding and therefore implant loosening in the long term. As yet there are no long-term clinical studies available to prove the benefits of these short-stem implants. Owing to this lack of clinical data, numerical simulation may be used as a predictor of longer term behaviour. This finite element study predicted both the primary stability and long-term stability of a short-stem implant. The primary implant stability was evaluated in terms of interface micromotion. This study found primary stability to fall within the critical threshold for osseointegration to occur. Longer term stability was evaluated using a strain-adaptive bone remodelling algorithm to predict the long-term behaviour of the bone in terms of bone mineral density (BMD) changes. No BMD loss was observed in the classical Gruen zones 1 and 7 and bone remodelling patterns were comparable with hip resurfacing results in the literature.
Robotics can lead to a reproducibly high-quality operative result for ear, nose, and throat patients
Authors: Coulson C J , Reid A P , Proops D W
Published: April 2010

The success rates and morbidity of operations on the ear, nose, and throat (ENT) have improved markedly in the last 20—25 years. This has been largely due to improved vision, by microscopes and endoscopes, and has led to a greatly reduced hospital stay. During this time there has been minimal improvement in surgical tools. This paper discusses the need for robotic tools, detailing the clinical constraints that proposed solutions need to adhere to, and presenting a recently trialled micro drilling robot for creating a cochleostomy in the cochlear implant procedure.
Does the choice of stair gait cycle affect resulting knee joint kinematics and moments?
Authors: Whatling G M , Holt C A
Published: April 2010

Stair gait is a useful activity for the assessment of knee function. The aim of this study was to determine whether knee joint kinematics and moments are affected by the choice of stair gait cycle (SGC) and the step used to measure ground reaction forces (GRFs). This was investigated through motion analysis of ten non-pathological subjects as they ascended and descended a four-step staircase. The SGCs compared for ascent were, first, step 1 (measuring GRFs) to step 3 and, second, step 2 (measuring GRFs) to step 4, and vice versa for stair descent. Knee joint kinematics were not significantly influenced by the choice of SGC. For ascent, significantly larger peak adduction moments were measured for SGCs beginning on step 1 (0.30 ± 0.08 N m/kg) than for SGCs beginning on step 2 (0.23 ± 0.09 N m/kg). For descent, the second flexion moment peak was found to be significantly larger for SGCs ending on step 2 (1.17 ± 0.25 N m/kg) than for SGCs ending on step 1 (0.97 ± 0.19 N m/kg), and the first adduction moment peak was found to be significantly larger for SGCs ending on step 2 (0.28 ± 0.15 N m/kg) than for SGCs ending on step 1 (0.21 ± 0.18 N m/kg). This study highlights important considerations when planning stair gait measurement protocols and comparing results from studies made by other laboratories.
Usefulness of cell-free plasma DNA, procalcitonin and C-reactive protein as markers of infection in febrile patients
Authors: Moreira Vanessa García , Prieto Belén , Rodríguez Julia San Martín , Álvarez Francisco V
Published: April 2010

Background

Circulating nucleic acids were discovered more than 60 y ago. With the recent developments in the study of circulating nucleic acids, its application in the diagnostic field has increased. The objective of this study was to assess the usefulness of the quantification of cell-free plasma DNA (CF-DNA) concentration in the diagnosis of infections in febrile patients and as a prognostic marker in septic patients.

Methods

Concentrations of CF-DNA, procalcitonin (PCT) and C-reactive protein (CRP) were measured in 110 febrile patients who were clinically diagnosed with fever of unknown origin, localized infection, sepsis or septic shock.

Results

Concentrations of CF-DNA increase according to the severity of the infection. The best cut-off point for predicting infection was 2800 GE (genome equivalents)/mL (sensitivity: 95.0%; specificity: 96.7%) and 14,000 GE/mL for sepsis prediction (sensitivity: 77.8%; specificity: 94.6%). Higher concentrations of CF-DNA were found in exitus septic patients than in survivors. The diagnostic efficiency of CF-DNA was similar to PCT and higher than CRP in infectious processes.

Conclusions

Normal concentrations of CF-DNA can exclude the presence of an infection in febrile patients, and very high concentrations (>10-fold over the normal reference range) stratify the severity of infections, showing a high prognostic value to predict mortality in the absence of other causes for elevated CF-DNA.
Enhancing hardiness among health-care workers: the perceptions of senior managers
Authors: Hague Ann , Leggat Sandra G
Published: April 2010

The purpose of this exploratory study was to understand ‘hardiness’ as defined and operationalized by senior health executives, and to explore the options for increasing the hardiness of the health-care workforce. Previous research has shown that hardiness is important in the workplace as a means to reduce or avoid the negative impact of stress, which then has an association with the maintenance of individual health. Hardiness has been thought to play an important role in assisting health-care workers deal with emotional and stressful work environments. In depth interviews were conducted with senior managers in a Victorian health service to explore hardiness and determine whether the senior executives had identified hardiness as a factor related to performance, how they recognized it within their staff and how hardiness might be enhanced within the organization. The senior managers were able to identify hardy members of their staff, whom they largely described as high performers. We argue that there is opportunity to strengthen health-care organizations by identifying and supporting hardy staff members. Our findings suggest that health-care organizations can teach the concept of hardiness, select hardy employees and develop strategies to assist employees to increase their levels of hardiness in the workplace.
Improving patient evaluation of hospital care and increasing their intention to recommend: Are they the same or different constructs?
Authors: Otani Koichiro , Herrmann Patrick A , Kurz Richard S
Published: April 2010

Many patient satisfaction studies consider patient satisfaction and intention to recommend as the same constructs. However, we propose to investigate the two constructs separately. This study has utilized patient satisfaction data with 32 hospitals in different locations to investigate how hospital discharged patients combine their attribute reactions to arrive at their evaluation of hospital care and their intention to recommend to others. A multiple linear regression analysis with a scatter term was conducted while controlling for age, gender, perceived health, educational attainment and race. The interpretation of the scatter term is presented with a story. There were 31,471 cases for the analysis, and the results show some similarities and critical differences between the two models. In conclusion, hospital managers are well advised to focus on improving nursing care first, and then staff care and environment in order to increase patient evaluation of hospital care and intention to recommend.
Trends and geographic variation of potentially avoidable hospitalizations in the veterans health-care system
Authors: Finegan Michael S , Gao Jian , Pasquale Donald , Campbell James
Published: April 2010

The rate of hospitalizations due to ambulatory care-sensitive conditions (ACSCs) has been widely accepted as an indicator of access and quality of primary care. This study aimed to examine the trends and geographic variation of ACSC hospitalizations in US veterans health-care system, to identify factors associated with ACSC hospitalizations and to develop a quality indicator that can monitor access and effectiveness of primary care at hospital level. Using fiscal years 1997–2007 data, we found total ACSC hospitalizations per 1000 ACSC patients decreased by 58%; ACSC hospitalizations as percentage of total hospitalizations decreased 9%. However, significant geographic variations of ACSC hospitalizations remained and we found that adjustment of case-mix or confounding factors was essential in making meaningful comparisons among hospitals in a health-care system. Further, this study also reveals that low-income veterans still had higher ACSC hospitalization rates and patient travel time less than 30 minutes to the nearest VA providers was associated with fewer ACSC hospitalizations, which possess important policy implications.
Ethical budgets: a critical success factor in implementing new public management accountability in health care
Authors: Bosa Iris M
Published: April 2010

New public management accountability is increasingly being introduced into health-care systems throughout the world – albeit with mixed success. This paper examines the successful introduction of new management accounting systems among general practitioners (GPs) as an aspect of reform in the Italian health-care system. In particular, the study examines the critical role played by the novel concept of an ‘ethical budget’ in engaging the willing cooperation of the medical profession in implementing change. Utilizing a qualitative research design, with in-depth interviews with GPs, hospital doctors and managers, along with archival analysis, the present study finds that management accounting can be successfully implemented among medical professionals provided there is alignment between the management imperative and the ethical framework in which doctors practise their profession. The concept of an ‘ethical budget’ has been shown to be an innovative and effective tool in achieving this alignment.
Age-related differential diagnosis of vaginal bleeding in postmenopausal women: a series of 3047 symptomatic postmenopausal women
Authors: Burbos Nikolaos , Musonda Patrick , Giarenis Ilias , Shiner Alice M , Giamougiannis Panagiotis , Morris Edward , Nieto Joaquin J
Published: April 2010

Objective

The aim of this study is to identify the causes of vaginal bleeding in different age groups of postmenopausal women. Also, we attempt to estimate the incidence of postmenopausal vaginal bleeding and endometrial cancer in a defined geographical area.

Study design

The study was conducted at a gynaecological oncology centre in the United Kingdom, between February 2006 and May 2009. Patients were investigated according to established evidence-based departmental guidelines.

Results

During the study period 3047 women were referred with postmenopausal vaginal bleeding. In 1356 women (44.5%) the endometrial thickness measured less than 5 mm on transvaginal ultrasound scan. Benign histology was found in 1144 women (37.5%). Benign endometrial polyps were the cause of bleeding in 10.1% of the cases. The incidence of endometrial cancer in our study population was 5%. The rate of postmenopausal vaginal bleeding during the study period peaks at the age of 55–59 years (25.9/1000 postmenopausal women/year) and declines thereafter. The peak incidence of endometrial cancer during the study period (12.6/10,000 postmenopausal women/year) was seen between the ages of 60 and 64 years and similarly declines with increasing age.

Conclusion

To our knowledge, this is the first population-based estimation of the incidence of genital tract bleeding and endometrial cancer among postmenopausal women in the United Kingdom. The results of this study showing the age-related differential diagnosis can be used to inform clinical practice when counselling postmenopausal women with vaginal bleeding.
Women with recurrent postmenopausal bleeding should be re-investigated but are not more likely to have endometrial cancer
Authors: Ronghe Rashmi , Gaudoin Marco
Published: April 2010

Objectives

We aimed to determine the prevalence of endometrial cancer in patients presenting with recurrent postmenopausal bleeding (PMB) after initial negative investigations.

Study design

This was a retrospective study carried out in a dedicated PMB clinic. All patients presenting with recurrent PMB between 1 January 2003 and 31 May 2009 were studied. All patients had transvaginal ultrasound, speculum examination and endometrial sampling attempted.

Main outcome measure

The prevalence of endometrial cancer in patients presenting with recurrent PMB after initial negative investigations.

Results

A total of 1536 women with PMB were seen over a period of 56 months. Sixty-six required definitive treatment after their first visit. One hundred and twenty-six re-presented with recurrent bleeding. The prevalence of endometrial cancer in women presenting for the first time with PMB was 3.04% whereas that in women presenting with recurrent PMB after initial negative investigations was 4%. One of these women re-presented within six months of initial visit and another within one year. All the other cancers were diagnosed more than one year after initial negative investigations (range 19.6–57.1 months). One woman had an endometrial cancer even though the endometrial thickness was less than 3 mm.

Conclusions

Women with recurrent PMB after initial negative investigations are no more likely to have endometrial cancer than those presenting for the first time but re-investigation is indicated if six months has elapsed.
Should transdermal rather than oral estrogens be used in menopausal hormone therapy?: a review
Authors: Fournier Agnès
Published: April 2010

The current evaluation of the benefit/risk ratio associated with menopausal hormone therapy (MHT) use is largely based on clinical trials which investigated the effects of oral treatments. Would MHT with transdermal estrogens be associated with a more favourable benefit/risk ratio? We reviewed the available epidemiologic evidence on that question. Epidemiologic studies were considered if they provided risk estimates of conditions which carry an important weight among menopausal women, and for which epidemiologic evidence of a possible link with MHT use is convincing: cardiovascular diseases, breast cancer, diabetes, colorectal cancer and hip fracture. We did not include studies with only surrogate measures. We found that the available information on the potential impact of the route of administration of MHT on the risk of our selected outcomes is limited. To date, epidemiologic data suggest that it has no impact on the risk of breast cancer and hip fracture. Results on the risk of coronary heart disease and colorectal cancer are inconsistent. Studies on stroke and diabetes risk are too few to allow meaningful conclusions. There is a suggestion that transdermal MHT may be less deleterious than oral MHT regarding venous thromboembolism which needs to be confirmed. The issue of the route of administration of MHT should remain an active area of research as part of an attempt to identify treatment modalities that would have the least potential for exerting adverse effects.
Treatment of premature ovarian failure trial: description of an ongoing clinical trial
Authors: Cartwright Beth , Robinson Jillian , Rymer Janice
Published: April 2010

Premature ovarian failure is a relatively common clinical condition, and carries important long-term health consequences. Estrogen replacement is recommended to alleviate unpleasant hypo-estrogenic symptoms and reduce long-term health risks. However, the most suitable form of estrogen replacement, and the exact effects of no treatment, is unknown. Surprisingly, little research has been carried out in this area. We describe the design of an ongoing clinical trial that will address these issues so that we can begin to provide evidence-based care for affected women.
Bioinformatic, structural, and functional analyses support release factor-like MTRF1 as a protein able to decode nonstandard stop codons beginning with adenine in vertebrate mitochondria
Authors: Young David J. , Edgar Christina D. , Murphy Jennifer , Fredebohm Johannes , Poole Elizabeth S. , Tate Warren P.
Published: April 2010

Vertebrate mitochondria use stop codons UAA and UAG decoded by the release factor (RF) MTRF1L and two reassigned arginine codons, AGA and AGG. A second highly conserved RF-like factor, MTRF1, which evolved from a gene duplication of an ancestral mitochondrial RF1 and not a RF2, is a good candidate for recognizing the nonstandard codons. MTRF1 differs from other RFs by having insertions in the two external loops important for stop codon recognition (tip of helix α5 and recognition loop) and by having key substitutions that are involved in stop codon interactions in eubacterial RF/ribosome structures. These changes may allow recognition of the larger purine base in the first position of AGA/G and, uniquely for RFs, only of G at position 2. In contrast, residues that support A and G recognition in the third position in RF1 are conserved as would be required for recognition of AGA and AGG. Since an assay with vertebrate mitochondrial ribosomes has not been established, we modified Escherichia coli RF1 at the helix α5 and recognition loop regions to mimic MTRF1. There was loss of peptidyl-tRNA hydrolysis activity with standard stop codons beginning with U (e.g., UAG), but a gain of activity with codons beginning with A (AAG in particular). A lower level of activity with AGA could be enhanced by solvent modification. These observations imply that MTRF1 has the characteristics to recognize A as the first base of a stop codon as would be required to decode the nonstandard codons AGA and AGG.
Histochemical Mapping of hnRNP A2/B1 in Rat Brain After Ischemia–Reperfusion Insults
Authors: Liu Yichen , Gao Yan , Wu Yan , Wu Yonghong , Wang Hangyan , Zhang Chenggang
Published: April 2010

Cerebral ischemia–reperfusion (I/R) insults result in neuronal cell death, brain tissue loss, and severe neurological deficits. However, the underlying mechanism is still not fully understood. Heterogeneous nuclear ribonucleoprotein (hnRNP) A2/B1 belongs to a family of RNA-binding proteins that plays a central role in pre-mRNA processing. Recent studies have revealed that hnRNP A2/B1 may be involved in the progress of I/R; therefore, the present study aimed to examine expression patterns of hnRNP A2/B1 to better understand posttranscriptional regulations in cerebral I/R insults. Focal cerebral I/R models were induced by right middle cerebral artery occlusion (MCAO) for 120 min followed by 3, 6, 12, 24, 48, and 72 hr of reperfusion in male Sprague-Dawley rats. We employed immunohistochemistry to examine expression of hnRNP A2/B1 in rat cerebral cortex (including cingulate cortex, striate cortex, temporal cortex, and piriform cortex) and hippocampus after I/R insults. Results showed that expression of hnRNP A2/B1 was significantly downregulated in cerebral cortex and hippocampus from 3 to 24 hr of reperfusion after MCAO for 120 min, but significantly upregulated at 48 hr of reperfusion. Unexpectedly, translocation of hnRNP A2/B1 from nucleus to cytoplasm and even to neurites was observed in cerebral cortex at 3 hr of reperfusion, reaching a peak at 24 hr of reperfusion, but not in hippocampus, indicating different posttranscriptional regulation patterns in different brain regions. Interestingly, translocation of hnRNP A2/B1 was only observed in cerebral cortex with MCAO but not in the opposite side, suggesting an I/R–specific expression pattern in the brain. Our data suggest that hnRNP A2/B1 participates in posttranscriptional regulation of neurons in cerebral cortex and hippocampus that suffered I/R insults, although posttranscriptional regulation is more extensive in neuronal cells of cerebral cortex than in hippocampus.
Spatial, Cellular, and Intracellular Localization of Na+/K+-ATPase in the Sterically Disposed Renal Tubules of Japanese Eel
Authors: Teranishi Keitaro , Kaneko Toyoji
Published: April 2010

The kidney plays a crucial role in the regulation of water and ion balances in both freshwater and seawater fishes. However, the complicated structures of the kidney hamper comprehensive understanding of renal functions. In this study, to investigate the structure of sterically disposed renal tubules, we examined spatial, cellular, and intracellular localization of Na+/K+-ATPase in the kidney of the Japanese eel. The renal tubule was composed of the first (PT-I) and second (PT-II) segments of the proximal tubule and the distal tubule (DT), followed by the collecting ducts (CDs). Light microscopic immunocytochemistry detected Na+/K+-ATPase along the renal tubules and CD; however, the subcellular distribution of the Na+/K+-ATPase immunoreaction varied among different segments. Electron microscopic immunocytochemistry further revealed that Na+/K+-ATPase was distributed on the basal infoldings of PT-I, PT-II, and DT cells. Three-dimensional analyses showed that the renal tubules meandered in a random pattern through lymphoid tissues, and then merged into the CD, which was aligned linearly. Among the different segments, the DT and CD cells showed more-intense Na+/K+-ATPase immunoreaction in freshwater eel than in seawater-acclimated eel, confirming that the DT and CD segments are important in freshwater adaptation, or hyperosmoregulation.
The Neural Stem/Progenitor Cell Marker Nestin Is Expressed in Proliferative Endothelial Cells, but Not in Mature Vasculature
Authors: Suzuki Sayuri , Namiki Jun , Shibata Shinsuke , Mastuzaki Yumi , Okano Hideyuki
Published: April 2010

Nestin is an intermediate filament protein that is known as a neural stem/progenitor cell marker. It is expressed in undifferentiated central nervous system (CNS) cells during development, but also in normal adult CNS and in CNS tumor cells. Additionally, nestin is expressed in endothelial cells (ECs) of CNS tumor tissues and of adult tissues that replenish by angiogenesis. However, the regulation of nestin expression in vascular endothelium has not been analyzed in detail. This study showed that nestin expression was observed in proliferating endothelial progenitor cells (EPCs), but not in mature ECs. In adherent cultured cells derived from bone marrow cells, EPCs that highly expressed nestin also expressed the endothelial marker CD31 and the proliferation marker Ki67. ECs cultured without growth factors showed attenuated nestin immunoreactivity as they matured. Trans-genic mice that carried the enhanced green fluorescent protein under the control of the CNS-specific second intronic enhancer of the nestin gene showed no reporter gene expression in EPCs. This indicated that the mechanisms of nestin gene expression were different in EPCs and CNS cells. Immunohistochemistry showed nestin expression in neovascular cells from two distinct murine models. Our results demonstrate that nestin can be used as a marker protein for neovascularization.
Pathologic Changes and Glucose Homeostasis According to Expression of Human Islet Amyloid Polypeptide in Type 2 Diabetic Patients
Authors: Park Ji Young , No Hee Sung , Ahn You Ran , Oh Seung Hoon , Kim Young Seok , Kim Sook Young , Jang Kee Taek , Kim Sun Wook , Chung Jae Hoon , Min Yong Ki , Heo Jin Seok , Choi Seong Ho , Choi Dong Wook , Lee Myung-Shik , Lee Moon Kyu , Kim Jae Hyeon , Kim Kwang-Won
Published: April 2010

The amount of amyloid detectable in islets varies, and is not always correlated with degree of β-cell loss. It has been hypothesized that islet amyloid polypeptide (IAPP) aggregation causes β-cell dysfunction. In this study, we investigated the relationship between IAPP expression and glucose homeostasis in pancreatectomized patients. Human pancreatic head tissues were collected from 46 pancreatic tumor patients. We divided the diabetic cases into two groups, patients with higher IAPP–expressing islets (DM-H) and patients with lower IAPP–expressing islets (DM-L), and compared both groups to patients with normal glucose tolerance (NGT). Interestingly, oral glucose tolerance test analyses showed that DM-L patients had significantly higher glucose levels and lower C-peptide levels than DM-H patients. Furthermore, the DM-H group showed a relative β-cell volume similar to that of the NGT group, as well as a significantly higher relative β-cell volume than the DM-L group. The DM-L group was significantly higher than the DM-H group, not only in the rates of replication and apoptosis, but also in the nuclear C/EBP homologous protein and the ratio of oligomer to IAPP. Thus, IAPP expression may not be an indicator of cell death induction. IAPP, including oligomer, may be an important determinant in the fate of islet β-cells. This manuscript contains online supplemental material at http://www.jhc.org . Please visit this article online to view these materials.
Differential Cellular Localization of Galectin-1 and Galectin-3 in the Regressing Corpus Luteum of Mice and Their Possible Contribution to Luteal Cell Elimination
Authors: Nio-Kobayashi Junko , Iwanaga Toshihiko
Published: April 2010

Galectin-1 and galectin-3, β-galactoside–binding lectins, are predominantly expressed in the regressing corpus luteum (CL) of mouse ovary. This study revealed the expression patterns and cellular localizations of galectins during CL formation and regression by ISH and IHC. Galectin-1 mRNA expression temporarily increased in active CL, preceding the expression of progesterone degradation enzyme 20α-hydroxysteroid dehydrogenase (20α-HSD), which represents functional luteolysis. The expressions of both galectin-1 and galectin-3 remarkably increased in the structurally regressing CL, which vigorously expressed 20α-HSD and contained abundant apoptotic luteal cells. Ultrastructurally, galectin-1– and galectin-3–immunoreactive cells were identified as fibroblasts and infiltrating macrophages, respectively. In addition, some populations of luteal cells themselves expressed galectin-3 in regressing CL and formed unique demarcation membranes in the cytoplasm, showing a non-typical apoptotic feature. Ovary of adult mice with repeated estrus cycles contained CL of three different generations. Among them, the old CL formed during previous estrus cycles consisted of galectin-3–positive luteal cells. The galectin-3–positive old CL was resistant to apoptosis and seemed to be eliminated by a mechanism different from apoptosis. The stage- and cell-specific expression of galectin in CL suggests its differential contribution to luteolysis, and this expression may be mediated by major regulatory molecules of CL function, prolactin and/or prostaglandin F2α.
GOAT: the master switch for the ghrelin system?
Authors: Romero Amparo , Kirchner Henriette , Heppner Kristy , Pfluger Paul T , Tschöp Matthias H , Nogueiras Ruben
Published: April 2010

The ghrelin–ghrelin receptor system is one of the most important mechanisms regulating energy balance and metabolism. Among other actions, central and peripheral administration of ghrelin increases food intake and adiposity. During the last years, many efforts have been made in the investigation of the cellular and molecular mechanisms modulating the effects of ghrelin. One particularity of this peptide hormone is its acylation at serine-3 with an eight-carbon fatty acid (octanoate), which confers its biological activity. Recent reports have demonstrated that the ghrelinO-acyltransferase (GOAT) is the enzyme that catalyzes ghrelin octanoylation. Therefore, all questions concerning the posttranslational acylation of ghrelin are of great interest for the complete understanding of this system. In this review, we summarize the discovery and characterization of GOAT, and remark the importance of GOAT as a novel and potential target that regulates the biological actions of ghrelin, revealing several therapeutical possibilities for the treatment of the metabolic syndrome.
A Fluorescence in Situ Hybridization System for Karyotyping Soybean
Authors: Findley Seth D , Cannon Steven , Varala Kranthi , Du Jianchang , Ma Jianxin , Hudson Matthew E , Birchler James A , Stacey Gary
Published: April 2010

The development of a universal soybean (Glycine max [L.] Merr.) cytogenetic map that associates classical genetic linkage groups, molecular linkage groups, and a sequence-based physical map with the karyotype has been impeded due to the soybean chromosomes themselves, which are small and morphologically homogeneous. To overcome this obstacle, we screened soybean repetitive DNA to develop a cocktail of fluorescent in situ hybridization (FISH) probes that could differentially label mitotic chromosomes in root tip preparations. We used genetically anchored BAC clones both to identify individual chromosomes in metaphase spreads and to complete a FISH-based karyotyping cocktail that permitted simultaneous identification of all 20 chromosome pairs. We applied these karyotyping tools to wild soybean, G. soja Sieb. and Zucc., which represents a large gene pool of potentially agronomically valuable traits. These studies led to the identification and characterization of a reciprocal chromosome translocation between chromosomes 11 and 13 in two accessions of wild soybean. The data confirm that this translocation is widespread in G. soja accessions and likely accounts for the semi-sterility found in some G. soja by G. max crosses.
On Relevance of Codon Usage to Expression of Synthetic and Natural Genes in Escherichia coli
Authors: Supek Fran , \#352;muc Tomislav
Published: April 2010

A recent investigation concluded that codon bias did not affect expression of green fluorescent protein (GFP) variants in Escherichia coli, while stability of an mRNA secondary structure near the 5′ end played a dominant role. We demonstrate that combining the two variables using regression trees or support vector regression yields a biologically plausible model with better support in the GFP data set and in other experimental data: codon usage is relevant for protein levels if the 5′ mRNA structures are not strong. Natural E. coli genes had weaker 5′ mRNA structures than the examined set of GFP variants and did not exhibit a correlation between the folding free energy of 5′ mRNA structures and protein expression.
Effect of Translesion DNA Polymerases, Endonucleases and RpoS on Mutation Rates inSalmonella typhimurium
Authors: Koskiniemi Sanna , Hughes Diarmaid , Andersson Dan I
Published: April 2010

It has been suggested that bacteria have evolved mechanisms to increase their mutation rate in response to various stresses and that the translesion DNA polymerase Pol IV under control of the LexA regulon and the alternative sigma factor RpoS are involved in regulating this mutagenesis. Here we examined in Salmonella enterica serovar Typhimurium LT2 the rates for four different types of mutations (rifampicin, nalidixic acid, and chlorate resistance and Lac+ reversion) during various growth conditions and with different levels of four translesion DNA polymerases (Pol II, Pol IV, Pol V, and SamAB) and RpoS. Constitutive derepression of the LexA regulon by a lexA(def) mutation had no effect on Lac+ reversion rates but increased the other three mutation rates up to 11-fold, and the contribution of the translesion DNA polymerases to this mutagenesis varied with the type of mutation examined. The increase in mutation rates in the lexA(def) mutant required the presence of the LexA-controlled UvrB protein and endonucleases UvrC and Cho. With regard to the potential involvement of RpoS in mutagenesis, neither an increase in RpoS levels conferred by artificial overexpression from a plasmid nor long-term stationary phase incubation or slow growth caused an increase in any of the four mutation rates measured, alone or in combination with overexpression of the translesion DNA polymerases. In conclusion, mutation rates are remarkably robust and no combination of growth conditions, induction of translesion DNA polymerases by inactivation of LexA, or increased RpoS expression could confer an increase in mutation rates higher than the moderate increase caused by derepression of the LexA regulon alone.
The Conserved miR-51 microRNA Family Is Redundantly Required for Embryonic Development and Pharynx Attachment in Caenorhabditis elegans
Authors: Shaw W Robert , Armisen Javier , Lehrbach Nicolas J , Miska Eric A
Published: April 2010

microRNAs (miRNAs) are ∼22-nucleotide small RNAs that act as endogenous regulators of gene expression by base-pairing with target mRNAs. Here we analyze the function of the six members of the Caenorhabditis elegans  miR-51 family of miRNAs (miR-51, miR-52, miR-53, miR-54, miR-55, miR-56). miR-51 family miRNAs are broadly expressed from mid-embryogenesis onward. The miR-51 family is redundantly required for embryonic development. mir-51 family mutants display a highly penetrant pharynx unattached (Pun) phenotype, where the pharyngeal muscle, the food pump of C. elegans, is not attached to the mouth. Unusually, the Pun phenotype in mir-51 family mutants is not due to a failure to attach, but instead a failure to maintain attachment during late embryogenesis. Expression of the miR-51 family in the mouth is sufficient to maintain attachment. The Fat cadherin ortholog CDH-3 is expressed in the mouth and is a direct target of the miR-51 family miRNAs. Genetic analysis reveals that miR-51 family miRNAs might act in part through CDH-3 to regulate pharynx attachment. This study is the first to assign a function to the miR-51/miR-100 miRNA family in any organism.
An mre11 Mutation That Promotes Telomere Recombination and an Efficient Bypass of Senescence
Authors: Joseph Immanual S , Kumari Alpana , Bhattacharyya Mrinal K , Gao Honghai , Li Bibo , Lustig Arthur J
Published: April 2010

Preventing the formation of dysfunctional telomeres is essential for genomic stability. In most organisms, the ribo-nucleoprotein reverse transcriptase telomerase is responsible for telomere GT-strand elongation. However, in telomerase-negative cells, low-frequency recombination mechanisms can avert lethality by elongating critically short telomeres. This study focuses on the involvement of the budding yeast Mre11 in telomere recombination and homeostasis. We have identified a novel allele of MRE11, mre11-A470T, that, in telomerase-positive cells, confers a semidominant decrease in telomere size and a recessive defect in telomere healing. In addition, mutant cells lack normal telomere size homeostasis. Telomerase-negative mre11-A470T cells display a Rad51-dependent bypass of replicative senescence via induction of a highly efficient type I-related recombination pathway termed type IA. The type IA pathway involves an amplification of subtelomeric Y′ elements, coupled with elongated and more heterogeneous telomere tracts relative to the short telomere size of type I survivors. The data have led us to propose the involvement of break-induced replication in telomere expansion. The differing phenotypes elicited by the mre11-A470T mutants in telomerase-positive and telomerase-negative cells have also led us to speculate that the telomere end structure may be modified differentially in mre11-A470T cells, directing the telomere into specific pathways.
The Host Response to Sepsis and Developmental Impact
Authors: Wynn James , Cornell Timothy T. , Wong Hector R. , Shanley Thomas P. , Wheeler Derek S.
Published: April 2010

Invasion of the human by a pathogen necessitates an immune response to control and eradicate the microorganism. When this response is inadequately regulated, systemic manifestations can result in physiologic changes described as “sepsis.” Recognition, diagnosis, and management of sepsis remain among the greatest challenges shared by the fields of neonatology and pediatric critical care medicine. Sepsis remains among the leading causes of death in both developed and underdeveloped countries and has an incidence that is predicted to increase each year. Despite these sobering statistics, promising therapies derived from preclinical models have universally failed to obviate the substantial mortality and morbidity associated with sepsis. Thus, there remains a need for well-designed epidemiologic and mechanistic studies of neonatal and pediatric sepsis to improve our understanding of the causes (both early and late) of deaths attributed to the syndrome. In reviewing the definitions and epidemiology, developmental influences, and regulation of the host response to sepsis, it is anticipated that an improved understanding of this host response will assist clinician-investigators in identifying improved therapeutic strategies.
Intimate Partner Violence: The Role of the Pediatrician
Authors: Thackeray Jonathan D , Hibbard Roberta , Dowd M. Denise ,   The Committee on Child Abuse and Neglect, and the Committee on Injury, Violence, and Poison Prevention
Published: April 2010

This Clinical Report was revised. See https://doi.org/10.1542/peds.2023-062509.

The American Academy of Pediatrics and its members recognize the importance of improving the physician's ability to recognize intimate partner violence (IPV) and understand its effects on child health and development and its role in the continuum of family violence. Pediatricians are in a unique position to identify abused caregivers in pediatric settings and to evaluate and treat children raised in homes in which IPV may occur. Children exposed to IPV are at increased risk of being abused and neglected and are more likely to develop adverse health, behavioral, psychological, and social disorders later in life. Identifying IPV, therefore, may be one of the most effective means of preventing child abuse and identifying caregivers and children who may be in need of treatment and/or therapy. Pediatricians should be aware of the profound effects of exposure to IPV on children.
Izolált pulmonalis arteriovenosus malformatio (PAVM) − 3 eset kapcsán
Authors: Füredi Árpád , Kecskés László István
Published: April 2010

Absztrakt

Bevezetés: A PAVM izolált formája ritka, és csak kevés VATS (Video-Assisted Thoracoscopic Surgery) resectiós eset ismertetése található a szakirodalomban. Mivel klinikai viselkedése bizonytalan, folyamatos növekedése és súlyos szövődményei (paradox embolisatio, stroke, abscessus cerebri stb.) miatt a legkevésbé invazív, de még megfelelően radikális kezelési módszert kell választani. Az embolisatiós terápia magában rejti az inkomplett kezelés és a véletlenszerű szisztémás embolisatio kockázatát, ezért inkább sebészi kimetszés mérlegelendő. Betegek és módszerek: Három beteget mutatunk be, akiket tünetmentes pulmonalis kerekárnyék (SPN) miatt vettünk fel további kivizsgálás és kezelés céljából. Két esetben VATS-ékresectiót, egy esetben axillaris thoracotomiából segmentectomiát végeztünk. Eredmények: Szövődménymentes posztoperatív szak után a betegeket egy héten belül emittáltuk. Kiújulást nem észleltünk (követés: 7, 3, 1 év). Következtetés: Gondolni kell erre a kórképre is annak érdekében, hogy a szövődményeket megelőzhessük. Ezekben az esetekben parenchymakímélő technika – mint amilyen az ékresectio – a választandó módszer, ha lehetséges VATS.
Interatomic potential to predict the binary metallic glass formation
Authors: Liu Baixin , Li Jiahao , Lai Wensheng
Published: April 2010

Interatomic potentials are constructed for eight representative binary metal systems covering various structural combinations and thermodynamic characteristics. On the basis of the constructed interatomic potentials, molecular dynamics simulations reveal that the physical origin of metallic glass formation is the crystalline lattice collapsing while solute atoms are exceeding the critical value, thus determining two critical solid solubilities for the system. For a binary metal system, the composition range bounded by the two determined critical solid solubilities is therefore defined as its intrinsic glass-forming range, or quantitative glass-forming ability.
Effect of presynthesis of Ta precursor on the formation of Ta nitrides
Authors: Park Jong-Chul , Pee Jae-Hwan , Park Hyung-Ho
Published: April 2010

We synthesized Ta3N5 by ammonolysis of Ta(OH)5. Ta(OH)5 was prepared by titration using TaCl5. The stirring speed and the amount of NH4OH to be added were important factors for controlling the particle size and formation of Ta(OH)5 during titration. During transformation of Ta(OH)5 to Ta3N5, the color changed from white to red. A small particle size and high level of formation of Ta(OH)5 improved nitridation, which was related to the color value. An x-ray diffractometer was used for phase identification. A scanning electron microscope was used to determine the microstructure, particle shape, and size. A colorimeter was used to obtain CIELab values. Ultraviolet–visible (UV–VIS) spectroscopy was carried out to determine the absorbance of colored powders. Thermogravimetry and a differential scanning calorimeter were used in air with a heating rate of 5 °C/min for thermal stability and behavior. An ON detector was used for detecting oxygen and nitrogen contents in Ta3N5.
Nano/micro-mechanical and tribological characterization of Ar, C, N, and Ne ion-implanted Si
Authors: Xu Zhi-Hui , Park Young-Bae , Li Xiaodong
Published: April 2010

Ion implantation has been widely used to improve the mechanical and tribological properties of single crystalline silicon, an essential material for the semiconductor industry. In this study, the effects of four different ion implantations, Ar, C, N, and Ne ions, on the mechanical and tribological properties of single crystal Si were investigated at both the nanoscale and the microscale. Nanoindentation and microindentation were used to measure the mechanical properties and fracture toughness of ion-implanted Si. Nano and micro scratch and wear tests were performed to study the tribological behaviors of different ion-implanted Si. The relationship between the mechanical properties and tribological behavior and the damage mechanism of scratch and wear were also discussed.
Microstructural and mechanical study of an Al matrix composite reinforced by Al-Cu-Fe icosahedral particles
Authors: Laplanche Guillaume , Joulain Anne , Bonneville Joël , Gauthier-Brunet Veronique , Dubois Sylvain , Kabir Tarik El
Published: April 2010

In this study, we produced an Al matrix composite material reinforced by Al-Cu-Fe particles of the icosahedral phase. The composite material was prepared using a hot isostatic pressure technique at T = 673 K and P = 180 MPa. The mechanical properties were investigated by compression tests performed at constant strain rate over the temperature range 290–823 K. The results show a vigorous strengthening effect resulting from the reinforcement particles. Strengthening is attributed to two main contributions arising from load transfer between the Al matrix and the reinforcement particles and from plastic deformation of the Al grains. The present results are compared with those obtained in a previous work on an Al-based composite reinforced by Al-Cu-Fe particles of the ω-tetragonal phase.
Study on the role of tarnishing film in stress-corrosion cracking of brass in Mattsson's solution
Authors: Zhang Cheng , Su Yanjing , Qiao Lijie , Chu Wuyang
Published: April 2010

In this paper, the influence of tarnishing film-induced stress and tarnishing film-induced brittle cracking on stress-corrosion cracking (SCC) of brass in Mattsson’s solution are investigated using hydrogen charging. Results showed that the SCC susceptibility of brass in Mattsson’s solution increased with the increase of tarnishing film-induced tensile stress. Also, the film-induced brittle cracking showed little effect on SCC susceptibility. From the results obtained, an improved SCC mechanism is proposed to explain the role of the tarnishing film-induced stress and the film-induced brittle cracking in SCC of brass in Mattsson’s solution. It seems that the film-induced brittle cracking is responsible for crack initiation of ductile brass. Also, the SCC susceptibility of brass in Mattsson’s solution was controlled by the growth rate of tarnishing film. Hydrogen enhanced the SCC susceptibility, which can be ascribed to the fact that hydrogen facilitates the tarnishing film growth.
Electronic structure and photoluminescence properties of Eu3+-activated KMPO4 (M = Sr, Ba)
Authors: Zhang Feng , Wang Yuhua , Zhang Zhiya , Liu Bitao
Published: April 2010

The electronic structures of KMPO4 (M = Sr, Ba) were calculated by the density functional theory with the local-density approximation. The calculated result shows that KSrPO4 and KBaPO4 are direct-band gap materials with direct energy gaps of 4.52 and 4.35 eV, respectively. Meanwhile, by analyzing the valence band structures of KMPO4 (M = Sr, Ba), the strength of binding of valence band electrons of KBaPO4 is stronger than that of KSrPO4. In addition, the photoluminescence (PL) properties of the intense red-emitting phosphors KM1–xPO4:Eu3+x (M = Sr, Ba) were investigated. The PL emission spectra excited at 393 nm are dominated by the peak at 611 nm due to the forced electric dipole 5D0–7F2 transition of Eu3+ ions, which is attributed to low local symmetry sites occupied by Eu3+ ions in these hosts. And the optimum integrated intensities for KSr1–xPO4:Eu3+x and KBa1–xPO4:Eu3+x are 1.3 times and 1.1 times of that for commercial Y2O3:Eu3+, respectively.