bluuebunny/crossref_metadata_2025 huggingface dataset:
The evolution of host associations in the parasitic wasp genus Ichneumon (Hymenoptera: Ichneumonidae): convergent adaptations to host pupation sites
Authors: Tschopp Andreas , Riedel Matthias , Kropf Christian , Nentwig Wolfgang , Klopfstein Seraina
Published: March 2013

Background

The diversification of organisms with a parasitic lifestyle is often tightly linked to the evolution of their host associations. If a tight host association exists, closely related species tend to attack closely related hosts; host associations are less stable if associations are determined by more plastic traits like parasitoid searching and oviposition behaviour. The pupal-parasitoids of the genusIchneumonattack a variety of macrolepidopteran hosts. They are either monophagous or polyphagous, and therefore offer a promissing system to investigate the evolution of host associations.Ichneumonwas previously divided into two groups based on general body shape; however, a stout shape has been suggested as an adaptation to buried host pupation sites, and might thus not represent a reliable phylogenetic character.

Results

We here reconstruct the first molecular phylogeny of the genusIchneumonusing two mitochondrial (CO1 and NADH1) and one nuclear marker (28S). The resulting phylogeny only supports monophyly ofIchneumonwhenIchneumon lugensGravenhorst, 1829 (formerly inChasmias,stat. rev.) andIchneumon deliratoriusLinnaeus, 1758 (formerlyCoelichneumon) are included. Neither parasitoid species that attack hosts belonging to one family nor those attacking butterflies (Rhopalocera) form monophyletic clades. Ancestral state reconstructions suggest multiple transitions between searching for hosts above versus below ground and between a stout versus elongated body shape. A model assuming correlated evolution between the two characters was preferred over independent evolution of host-searching niche and body shape.

Conclusions

Host relations, both in terms of phylogeny and ecology, evolved at a high pace in the genusIchneumon. Numerous switches between hosts of different lepidopteran families have occurred, a pattern that seems to be the rule among idiobiont parasitoids. A stout body and antennal shape in the parasitoid female is confirmed as an ecological adaptation to host pupation sites below ground and has evolved convergently several times. Morphological characters that might be involved in adaptation to hosts should be avoided as diagnostic characters for phylogeny and classification, as they can be expected to show high levels of homoplasy.
Transcriptome analysis of the parasite Encephalitozoon cuniculi: an in-depth examination of pre-mRNA splicing in a reduced eukaryote
Authors: Grisdale Cameron J , Bowers Lisa C , Didier Elizabeth S , Fast Naomi M
Published: March 2013

Background

The microsporidian Encephalitozoon cuniculi possesses one of the most reduced and compacted eukaryotic genomes. Reduction in this intracellular parasite has affected major cellular machinery, including the loss of over fifty core spliceosomal components compared to S. cerevisiae. To identify expression changes throughout the parasite’s life cycle and also to assess splicing in the context of this reduced system, we examined the transcriptome of E. cuniculi using Illumina RNA-seq.

Results

We observed that nearly all genes are expressed at three post-infection time-points examined. A large fraction of genes are differentially expressed between the first and second (37.7%) and first and third (43.8%) time-points, while only four genes are differentially expressed between the latter two. Levels of intron splicing are very low, with 81% of junctions spliced at levels below 50%. This is dramatically lower than splicing levels found in two other fungal species examined. We also describe the first case of alternative splicing in a microsporidian, an unexpected complexity given the reduction in spliceosomal components.

Conclusions

Low levels of splicing observed are likely the result of an inefficient spliceosome; however, at least in one case, splicing appears to be playing a functional role. Although several RNA decay genes are encoded in E. cuniculi, the lack of a few key players could be reducing decay levels and therefore increasing the proportion of unspliced transcripts. Significant proportions of genes are differentially expressed in the first forty-eight hours but not after, indicative of genetic changes that precede the intracellular to infective stage transition.
Diversity of endophytic fungi and screening of fungal paclitaxel producer from Anglojap yew, Taxus x media
Authors: Xiong Zhi-Qiang , Yang Ying-Ying , Zhao Na , Wang Yong
Published: March 2013

Background

Endophytic fungi represent underexplored resource of novel lead compounds and have a capacity to produce diverse class of plant secondary metabolites. Here we investigated endophytic fungi diversity and screening of paclitaxel-producing fungi from Taxus x media.

Results

Eighty-one endophytic fungi isolated from T. media were grouped into 8 genera based on the morphological and molecular identification. Guignardia and Colletotrichum were the dominant genera, whereas the remaining genera were infrequent groups. The genera Glomerella and Gibberella were first reported in Taxus. Three representative species of the distinct genera gave positive hits by molecular marker screening and were capable of producing taxol which were validated by HPLC-MS. Among these 3 taxol-producing fungi, the highest yield of taxol was 720 ng/l by Guignardia mangiferae HAA11 compared with those of Fusarium proliferatum HBA29 (240 ng/l) and Colletotrichum gloeosporioides TA67 (120 ng/l). This is the first report of taxol producer from Guignardia. Moreover, the lower similarities of ts and bapt between microbial and plant origin suggested that fungal taxol biosynthetic cluster might be repeatedly invented during evolution, nor horizontal gene transfer from Taxus species.

Conclusions

Taxol-producing endophytic fungi could be a fascinating reservoir to generate taxol-related drug lead and to elucidate the remained 5 unknown genes or the potential regulation mechanism in the taxol biosynthesis pathway.
An assessment of the vulnerability of carotid plaques: a comparative study between intraplaque neovascularization and plaque echogenicity
Authors: Zhou Yangyang , Xing Yingqi , Li Yan , Bai Yang , Chen Ying , Sun Xiaofeng , Zhu Yingqiao , Wu Jiang
Published: March 2013

Background

Carotid plaque echolucency as detected by Color Doppler ultrasonography (CDUS) has been used as a potential marker of plaque vulnerability. However, contrast-enhanced ultrasound (CEUS) has recently been shown to be a valuable method to evaluate the vulnerability and neovascularization within carotid atherosclerotic plaques. The aim of this study was to compare CEUS and CDUS in the assessment of plaque vulnerability using transcranial color Doppler (TCD) monitoring of microembolic signals (MES) as a reference technique.

Methods

A total of 46 subjects with arterial stenosis (≥ 50%) underwent a carotid duplex ultrasound, TCD monitoring of MES and CEUS (SonoVue doses of 2.0 mL) within a span of 3 days. The agreement between the CEUS, CDUS, and MES findings was assessed with a chi-square test. A p-value less than 0.05 was considered statistically significant.

Results

Neovascularization was observed in 30 lesions (44.4%). The vascular risk factors for stroke were similar and there were no age or gender differences between the 2 groups. Using CEUS, MES were identified in 2 patients (12.5%) within class 1 (non-neovascularization) as opposed to 15 patients (50.0%) within class 2 (neovascularization) (p = 0.023). CDUS revealed no significant differences in the appearance of the MES between the 2 groups (hyperechoic and hypoechoic) (p = 0.237).

Conclusion

This study provides preliminary evidence to suggest that intraplaque neovascularization detected by CEUS is associated with the presence of MESs, where as plaque echogenicity on traditional CDUS does not. These findings argue that CEUS may better identify high-risk plaques.
Comparative psychometric analyses of the SCL-90-R and its short versions in patients with affective disorders
Authors: Prinz Ulrich , Nutzinger Detlev O , Schulz Holger , Petermann Franz , Braukhaus Christoph , Andreas Sylke
Published: March 2013

Background

Despite the widespread application of Symptom Checklist 90-R (SCL-90-R), its psychometric weaknesses have repeatedly been noted. This study aimed to comparatively assess the psychometric properties of the SCL-90-R scales and the scales of its short versions Brief Symptom Inventory (BSI), Symptom Checklist-27 (SCL-27), Brief Symptom Inventory-18 (BSI-18), Symptom Checklist-14 (SCL-14), and Symptom Checklist short version-9 (SCL-K-9) in patients with affective disorders.

Methods

The data of 2,727 patients within the main treatment group of affective disorders were assessed according to the DSM-IV. Patients completed the SCL-90-R and Beck Depression Inventory (BDI).

Results

There were no significant differences regarding the internal consistency of the SCL-90-R scales and the scales of the short versions. The dimensional structure was only supported for the short versions BSI-18, SCL-14 and SCL-K-9. The assessment of convergent validity revealed high correlations. With regard to the discriminant validity, there were medium correlations. With regard to the sensitivity of change, no significant differences between the scales were found.

Conclusions

In summary, the scales of the short versions show mostly satisfactory psychometric properties in comparison to the scales of the SCL-90-R. The results support the application of the short versions as screening instruments, especially the BSI-18, and more economic variants of the SCL-90-R covering a wide range of psychopathological symptoms.
Which criteria should be used to define type 2 diabetes remission after bariatric surgery?
Authors: Ramos-Levi Ana M , Cabrerizo Lucio , Matía Pilar , Sánchez-Pernaute Andrés , Torres Antonio J , Rubio Miguel A
Published: March 2013

Background

Comparison of diabetes remission rates after bariatric surgery using two different models of criteria.

Methods

Retrospective analysis of data from 110 patients with type 2 diabetes and morbid obesity who underwent bariatric surgery, preoperatively and at 18-month follow-up. Comparison of two models of remission: 1) 2009 consensus statement criteria; 2) simple criteria using ADA’s HbA1c diabetes diagnostic cut-off values.

Results

Patients’ mean ± SD preoperative characteristics were: age 53.3 ± 9.5 years, BMI 43.6 ± 5.5 kg/m2, HbA1c 7.9 ± 1.8%, duration of diabetes 7.6 ± 7.5 years. 44.5% of patients with previous insulin therapy. With 2009 consensus statement criteria: complete, partial and no remission in 50%, 12.7% and 37.3%, respectively; with HbA1c criteria: 50%, 15% and 34.5% in the analogous categories (p = 0.673).

Conclusions

We suggest a simpler approach to evaluate diabetes remission after bariatric surgery, following the rationale of the definition of diabetes itself.
Relationship between the population incidence of pertussis in children in New South Wales, Australia and emergency department visits with cough: a time series analysis
Authors: Cashmore Aaron W , Muscatello David J , Merrifield Alistair , Spokes Paula , Macartney Kristine , Jalaludin Bin B
Published: March 2013

Background

Little is known about the potential of syndromic surveillance to provide early warning of pertussis outbreaks. We conducted a time series analysis to assess whether an emergency department (ED) cough syndrome would respond to changes in the incidence of pertussis in children aged under 10 years in New South Wales (NSW), Australia, and to evaluate the timing of any association. A further aim was to assess the lag between the onset of pertussis symptoms and case notification in the infectious diseases surveillance system in NSW.

Methods

Using routinely collected data, we prepared a daily count time series of visits to NSW EDs assigned a provisional diagnosis of cough. Separate daily series were prepared for three independent variables: notifications of cases of pertussis and influenza and ED visits with bronchiolitis (a proxy measure of respiratory syncytial virus (RSV) infection). The study period was 1/1/2007-31/12/2010. A negative binomial multivariate model was used to assess associations between the outcome and independent variables. We also evaluated the median delay in days between the estimated onset of a case of pertussis and the date the local public health authority was notified of that case.

Results

When notified pertussis increased by 10 cases in one day, ED visits with cough increased by 5.2% (95% confidence interval (CI): 0.5%-10.0%) seven days later. Daily increases in the other independent variables had a smaller impact on cough visits. When notified influenza increased by 10 cases in one day, ED visits with cough increased by 0.8% (95% CI: 0%-1.7%) seven days later. When ED visits with bronchiolitis increased by 10 visits in one day, ED visits with cough increased by 4.8% (95% CI: 1.2%-8.6%) one day earlier. The median interval between estimated onset of pertussis and case notification was seven days.

Conclusions

Pertussis appears to be an important driver of ED visits with cough in children aged under 10 years. However, the median delay in notification of cases of pertussis was similar to the lag in the pertussis-associated short-term increases in ED visits with cough. Elevations in RSV and influenza activity may also explain increases in the ED cough syndrome. Real time monitoring of ED visits with cough in children is therefore unlikely to consistently detect a potential outbreak of pertussis before passive surveillance.
Zinc protects against diabetes-induced pathogenic changes in the aorta: roles of metallothionein and nuclear factor (erythroid-derived 2)-like 2
Authors: Miao Xiao , Wang Yonggang , Sun Jian , Sun Weixia , Tan Yi , Cai Lu , Zheng Yang , Su Guanfang , Liu Quan , Wang Yuehui
Published: March 2013

Background

Cardiovascular diseases remain a leading cause of the mortality world-wide, which is related to several risks, including the life style change and the increased diabetes prevalence. The present study was to explore the preventive effect of zinc on the pathogenic changes in the aorta.

Methods

A genetic type 1 diabetic OVE26 mouse model was used with/without zinc supplementation for 3 months. To determine gender difference either for pathogenic changes in the aorta of diabetic mice or for zinc protective effects on diabetes-induced pathogenic changes, both males and females were investigated in parallel by histopathological and immunohistochemical examinations, in combination of real-time PCR assay.

Results

Diabetes induced significant increases in aortic oxidative damage, inflammation, and remodeling (increased fibrosis and wall thickness) without significant difference between genders. Zinc treatment of these diabetic mice for three months completely prevented the above pathogenic changes in the aorta, and also significantly up-regulated the expression and function of nuclear factor (erythroid-derived 2)-like 2 (Nrf2), a pivotal regulator of anti-oxidative mechanism, and the expression of metallothionein (MT), a potent antioxidant. There was gender difference for the protective effect of zinc against diabetes-induced pathogenic changes and the up-regulated levels of Nrf2 and MT in the aorta.

Conclusions

These results suggest that zinc supplementation provides a significant protection against diabetes-induced pathogenic changes in the aorta without gender difference in the type 1 diabetic mouse model. The aortic protection by zinc against diabetes-induced pathogenic changes is associated with the up-regulation of both MT and Nrf2 expression.
The novel mTOR inhibitor CCI-779 (temsirolimus) induces antiproliferative effects through inhibition of mTOR in Bel-7402 liver cancer cells
Authors: Li Shuyu , Liang Yan , Wu Manlin , Wang Xiaojing , Fu Haixia , Chen Yuhao , Wang Zhigang
Published: March 2013

Background

Liver cancer is one of the most frequent cancers in the world. Targeted therapy of cancer with specific inhibitors is developing and has shown promising antitumor efficacy. CCI-779 (temsirolimus), a specific inhibitor of mTOR (mammalian target of rapamycin), can block the mTOR signaling pathway. Here, we systematically examined the expression of mTOR and its downstream targets in liver cancer cells and normal liver cells, then investigated inhibitory effects of CCI-779 on mTOR signaling pathway and its role in regulating liver cancer cell growth.

Methods

The expression of mTOR and its downstream targets in Bel-7402 liver cancer cells and HL-7702 normal liver cells were examined by western blot. The mTOR specific inhibitor (CCI-779) was used to treat Bel-7402 cells to identify its effects on Bel-7402 cell growth and activity of mTOR signaling pathway in vitro. Cell viability tests were performed after the treatment of CCI-779. Western blot was applied to assess the changes of mTOR pathway and flow cytometry was used to analyze cell cycle of Bel-7402 cells after the treatment of CCI-779.

Results

mTOR, p70S6K, S6, and 4EBP1 were overexpressed in Bel-7402 cells compared with HL-7702 cells. Bel-7402 cells were sensitive to CCI-779. The survival rate of the cells treated with CCI-779 over 0.312 μM was significantly different compared with that of control (P < 0.05). CCI-779 inhibited the phosphorylation of mTOR (Ser2448), p70S6K (Thr389), S6 (Ser240/244), and 4EBP1 (Thr37/46) in different grades and the expressions of p70S6K, S6, and 4EBP1. As a result, CCI-779 induced a dose-dependent decrease in cell proliferation, G1/S arrest and damage of cell shape.

Conclusions

Taken together, these data showed that CCI-779 can inhibit mTOR signaling and proliferation in Bel-7402 liver cancer cells in vitro. It offers a therapeutic intervention through inhibition of mTOR as a potential strategy for liver cancer.
Self-similarity property of acoustic data acquired in shallow water environment
Authors: Chen Jin , Duan Fa-jie , Jiang Jia-jia , Zhang Baoju , Tong Ying , He Jun
Published: March 2013

Underwater acoustic modeling in shallow water environment is difficult since sound waves reflect several times between the surface and the water bottom. This article discusses an underwater acoustic characteristics analysis method based on self-similarity. It is found that acoustic signal has good self-similarity in shallow water. The actual towed hydrophone linear array was established and it was used for underwater acoustic signal acquisition experiment in Qilihai Reservoir which is located in the suburb of Tianjin, China. It can be derived that the signals acquired by hydrophones have self-similarity by the analysis of the variance of m-aggregated time series. It is proved that the characteristics of self-similarity can be used for the sound pulse propagation in shallow water.
Calcium-deficiency assessment and biomarker identification by an integrated urinary metabonomics analysis
Authors: Wang Maoqing , Yang Xue , Wang Fan , Li Ran , Ning Hua , Na Lixin , Huang Yifan , Song Yue , Liu Liyan , Pan Hongzhi , Zhang Qiuju , Fan Lijun , Li Ying , Sun Changhao
Published: March 2013

Background

Calcium deficiency is a global public-health problem. Although the initial stage of calcium deficiency can lead to metabolic alterations or potential pathological changes, calcium deficiency is difficult to diagnose accurately. Moreover, the details of the molecular mechanism of calcium deficiency remain somewhat elusive. To accurately assess and provide appropriate nutritional intervention, we carried out a global analysis of metabolic alterations in response to calcium deficiency.

Methods

The metabolic alterations associated with calcium deficiency were first investigated in a rat model, using urinary metabonomics based on ultra-performance liquid chromatography coupled with quadrupole time-of-flight tandem mass spectrometry and multivariate statistical analysis. Correlations between dietary calcium intake and the biomarkers identified from the rat model were further analyzed to confirm the potential application of these biomarkers in humans.

Results

Urinary metabolic-profiling analysis could preliminarily distinguish between calcium-deficient and non-deficient rats after a 2-week low-calcium diet. We established an integrated metabonomics strategy for identifying reliable biomarkers of calcium deficiency using a time-course analysis of discriminating metabolites in a low-calcium diet experiment, repeating the low-calcium diet experiment and performing a calcium-supplement experiment. In total, 27 biomarkers were identified, including glycine, oxoglutaric acid, pyrophosphoric acid, sebacic acid, pseudouridine, indoxyl sulfate, taurine, and phenylacetylglycine. The integrated urinary metabonomics analysis, which combined biomarkers with regular trends of change (types A, B, and C), could accurately assess calcium-deficient rats at different stages and clarify the dynamic pathophysiological changes and molecular mechanism of calcium deficiency in detail. Significant correlations between calcium intake and two biomarkers, pseudouridine (Pearson correlation, r = 0.53, P = 0.0001) and citrate (Pearson correlation, r = -0.43, P = 0.001), were further confirmed in 70 women.

Conclusions

To our knowledge, this is the first report of reliable biomarkers of calcium deficiency, which were identified using an integrated strategy. The identified biomarkers give new insights into the pathophysiological changes and molecular mechanisms of calcium deficiency. The correlations between calcium intake and two of the biomarkers provide a rationale or potential for further assessment and elucidation of the metabolic responses of calcium deficiency in humans.
Enhancement by Interleukin-1β of AMPA and NMDA Receptor-Mediated Currents in Adult Rat Spinal Superficial Dorsal Horn Neurons
Authors: Liu Tao , Jiang Chang-Yu , Fujita Tsugumi , Luo Shi-Wen , Kumamoto Eiichi
Published: March 2013

Background

Proinflammatory cytokine interleukin-1β (IL-1β) released from spinal microglia plays an important role in the maintenance of acute and chronic pain states. However, the cellular basis of this action remains poorly understood. Using whole-cell patch-clamp recordings, we examined the action of IL-1β on AMPA- and NMDA-receptor-mediated currents recorded from substantia gelatinosa (SG) neurons of adult rat spinal cord slices which are key sites for regulating nociceptive transmission from the periphery.

Results

AMPA- and NMDA-induced currents were increased in peak amplitude by IL-1β in a manner different from each other in SG neurons. These facilitatory actions of IL-1β were abolished by IL-1 receptor (IL-1R) antagonist (IL-1ra), which by itself had no detectable effects on AMPA- and NMDA-induced currents. The AMPA- but not NMDA-induced current facilitated by IL-1β was recovered to control level 30 min after IL-1β washout and largely depressed in Na+-channel blocker tetrodotoxin-containing or nominally Ca2+-free Krebs solution. Minocycline, a microglia inhibitor, blocked the facilitatory effect of IL-1β on AMPA- but not NMDA-induced currents, where minocycline itself depressed NMDA- but had not any effects on AMPA-induced currents.

Conclusions

IL-1β enhances AMPA and NMDA responses in SG neurons through IL-1R activation; the former but not latter action is reversible and due to an increase in neuronal activity in a manner dependent on extracellular Ca2+ and minocycline. It is suggested that AMPA and NMDA receptors are positively modulated by IL-1β in a manner different from each other; the former but not latter is mediated by a neurotransmitter released as a result of an increase in neuronal activity. Since IL-1β contributes to nociceptive behavior induced by peripheral nerve or tissue injury, the present findings also reveal an important cellular link between neuronal and glial cells in the spinal dorsal horn.
Genetic analysis of peste des petits ruminants virus from Pakistan
Authors: Anees Muhammad , Shabbir Muhammad Zubair , Muhammad Khushi , Nazir Jawad , Shabbir Muhammad Abu Bakar , Wensman Jonas J , Munir Muhammad
Published: March 2013

Background

Peste des petits ruminants (PPR) is an endemic and highly contagious disease in small ruminants of Pakistan. Despite the fact that an effective vaccine is available, outbreaks are regularly occurring in the country. Thus so far, the diagnosis has primarily been made based on clinical outcome or serology. This study was carried out to characterize PPRV from an emerging wave of outbreaks from Punjab, Pakistan.

Results

A total of 32 blood samples from five different flocks were tested with real-time PCR for the presence of PPRV genome. The samples detected positive in real-time PCR (n = 17) were subjected to conventional PCR for the amplification of the nucleoprotein (N) gene. Phylogenetic analysis of the sequenced N genes (n = 8) indicated the grouping of all the sequences in lineage IV along with PPRV strains from Asian and Middle East. However, interestingly sequences were divided into two groups. One group of viruses (n = 7) clustered with previously characterized Pakistani isolates whereas one strain of PPRV was distinct and clustered with Saudi Arabian and Iranian strains of PPRV.

Conclusions

Results demonstrated in this study expanded the information on the genetic nature of different PPRV population circulating in small ruminants. Such information is essential to understand genetic nature of PPRV strains throughout the country. Proper understanding of these viruses will help to devise control strategies in PPRV endemic countries such as Pakistan.
Activated charcoal-mediated RNA extraction method for Azadirachta indica and plants highly rich in polyphenolics, polysaccharides and other complex secondary compounds
Authors: Rajakani Raja , Narnoliya Lokesh , Sangwan Neelam Singh , Sangwan Rajender Singh , Gupta Vikrant
Published: March 2013

Background

High quality RNA is a primary requisite for numerous molecular biological applications but is difficult to isolate from several plants rich in polysaccharides, polyphenolics and other secondary metabolites. These compounds either bind with nucleic acids or often co-precipitate at the final step and many times cannot be removed by conventional methods and kits. Addition of vinyl-pyrollidone polymers in extraction buffer efficiently removes polyphenolics to some extent, but, it failed in case ofAzadirachta indicaand several other medicinal and aromatic plants.

Findings

Here we report the use of adsorption property of activated charcoal (0.03%–0.1%) in RNA isolation procedures to remove complex secondary metabolites and polyphenolics to yield good quality RNA fromAzadirachta indica. We tested and validated our modified RNA isolation method across 21 different plants includingAndrographis paniculata,Aloe vera,Rosa damascena,Pelargonium graveolens, Phyllanthus amarusetc. from 13 other different families, many of which are considered as tough system for isolating RNA. The A260/280 ratio of the extracted RNA ranged between 1.8-2.0 and distinct 28S and 18S ribosomal RNA bands were observed in denaturing agarose gel electrophoresis. Analysis using Agilent 2100 Bioanalyzer revealed intact total RNA yield with very good RNA Integrity Number.

Conclusions

The RNA isolated by our modified method was found to be of high quality and amenable for sensitive downstream molecular applications like subtractive library construction and RT-PCR. This modified RNA isolation procedure would aid and accelerate the biotechnological studies in complex medicinal and aromatic plants which are extremely rich in secondary metabolic compounds.
Partial loss of CovS function in Streptococcus pyogenes causes severe invasive disease
Authors: Tatsuno Ichiro , Okada Ryo , Zhang Yan , Isaka Masanori , Hasegawa Tadao
Published: March 2013

Background

CovRS (or CsrRS) is a two-component regulatory system that regulates the production of multiple virulence factors in Streptococcus pyogenes. covS mutations are often found in isolates recovered from mice that have been experimentally infected with S. pyogenes and covS mutations enhance bacterial virulence in an invasive infection mouse model. In addition, covS mutations were detected more frequently in a panel of clinical isolates from severe invasive streptococcal infections than those from non-severe infections. Thus, covS mutations may be associated with the onset of severe invasive infections.

Results

Known covS mutations were divided into two groups: (i) frameshift mutations that caused a deletion of functional regions and (ii) point mutations that caused single (or double) amino acid(s) substitutions. Frameshift mutations are frequent in mouse-passaged isolates, whereas point mutations are frequent in clinical isolates. The functions of CovS proteins with a single amino acid substitution in clinical isolates were estimated based on the streptococcal pyrogenic exotoxin B (SpeB) production and NAD+-glycohydrolase (NADase) activity, which are known to be regulated by the CovRS system. Point mutations partially, but not completely, impaired the function of the covS alleles. We also investigated some of the benefits that a partial loss of function in covS alleles with point mutations might confer on clinical isolates. We found that covS knockout mutants (ΔcovS strains) had an impaired growth ability in a normal atmosphere in Todd Hewitt broth compared with parental isolates having wild-type or point-mutated covS.

Conclusions

The loss of CovS proteins in S. pyogenes may confer greater virulence, but bacteria may also lose the ability to respond to certain external signals recognized by CovS. Therefore, point mutations that retain the function of CovS and confer hypervirulence may have natural selective advantages.
Clinical implication of Time To Brain Metastasis (TTBM) according to breast cancer subtypes
Authors: Ahn Hee Kyung , Park Yeon Hee , Lee Su Jin , Park Silvia , Maeng Chi Hoon , Park Won , Choi Doo Ho , Hur Seung Jae , Ahn Jin Seok , Im Young-Hyuck
Published: March 2013

The aims of the present study were to investigate how breast cancer (BC) subtypes and treatment affect time to brain metastasis (TTBM). We retrospectively investigated 189 consecutive patients who were diagnosed with brain metastasis (BM) from BC between 2000 and 2009 at Samsung Medical Center. We analyzed TTBM from initial diagnosis of metastatic BC according to subtypes and trastzumab (T) administration before BM diagnosis. The median age of 189 BM patients from BC was 48 years. We divided TTBM into four groups considering BC subtypes and treatment; HR-positive/HER2-negative (n=45), HER2-positive with T before BM development (n=47), HER2-positive without T before BM development (n=39), and TNBC (n=58). The median TTBMs for each group were 17.5 months, 13.7 months, 5.8 months, and 2.9 months, respectively (p<0.001). HER2-positive without T (HR 1.892, p=0.008) and TNBC (HR 1.652, p=0.023) were independently associated with shorter TTBM. In multivariate analysis, HER2-positive without T (hazard ratio 1.725, p=0.002) and TNBC (hazard ratio 1.579, p=0.022) were independent risk factors for worse metastatic OS compared with HR-positive/HER2-negative subtype. TTBMs were shorter in patients with HER2-positive without T and TNBC among BC subtypes. Prospective clinical study for high risk patients for early BM is warranted.
PAR-2, LGL-1 and the CDC-42 GAP CHIN-1 act in distinct pathways to maintain polarity in the C. elegans embryo
Authors: Beatty Alexander , Morton Diane G. , Kemphues Kenneth
Published: March 2013

In the one-cell C. elegans embryo, polarity is maintained by mutual antagonism between the anterior cortical proteins PAR-3, PKC-3, PAR-6 and CDC-42, and the posterior cortical proteins PAR-2 and LGL-1 on the posterior cortex. The mechanisms by which these proteins interact to maintain polarity are incompletely understood. In this study, we investigate the interplay among PAR-2, LGL-1, myosin, the anterior PAR proteins and CDC-42. We find that PAR-2 and LGL-1 affect cortical myosin accumulation by different mechanisms. LGL-1 does not directly antagonize the accumulation of cortical myosin and instead plays a role in regulating PAR-6 levels. By contrast, PAR-2 likely has separate roles in regulating cortical myosin accumulation and preventing the expansion of the anterior cortical domain. We also provide evidence that asymmetry of active CDC-42 can be maintained independently of LGL-1 and PAR-2 by a redundant pathway that includes the CDC-42 GAP CHIN-1. Finally, we show that, in addition to its primary role in regulating the size of the anterior cortical domain via its binding to PAR-6, CDC-42 has a secondary role in regulating cortical myosin that is not dependent on PAR-6.
Extramacrochaetae imposes order on the Drosophila eye by refining the activity of the Hedgehog signaling gradient
Authors: Spratford Carrie M. , Kumar Justin P.
Published: March 2013

The compound eye of Drosophila melanogaster is configured by a differentiating wave, the morphogenetic furrow, that sweeps across the eye imaginal disc and transforms thousands of undifferentiated cells into a precisely ordered repetitive array of 800 ommatidia. The initiation of the furrow at the posterior margin of the epithelium and its subsequent movement across the eye field is controlled by the activity of the Hedgehog (Hh) signaling pathway. Differentiating photoreceptors that lie behind the furrow produce and secrete the Hh morphogen, which is captured by cells within the furrow itself. This leads to the stabilization of the full-length form of the zinc-finger transcription factor Cubitus interruptus (Ci155), the main effector of Hh signaling. Ci155 functions as a transcriptional activator of a number of downstream targets, including decapentaplegic (dpp), a TGFβ homolog. In this report, we describe a mechanism that is in place within the fly retina to limit Hh pathway activity within and ahead of the furrow. We demonstrate that the helix-loop-helix (HLH) protein Extramacrochaetae (Emc) regulates Ci155 levels. Loss of emc leads to an increase in Ci155 levels, nuclear migration, apical cell constriction and an acceleration of the furrow. We find that these roles are distinct from the bHLH protein Hairy (H), which we show restricts atonal (ato) expression ahead of the furrow. Secondary furrow initiation along the dorsal and ventral margins is blocked by the activity of the Wingless (Wg) pathway. We also show that Emc regulates and cooperates with Wg signaling to inhibit lateral furrow initiation.
Five-year results of a randomised controlled trial comparing mobile and fixed bearings in total knee replacement
Authors: Breeman S. , Campbell M. K. , Dakin H. , Fiddian N. , Fitzpatrick R. , Grant A. , Gray A. , Johnston L. , MacLennan G. S. , Morris R. W. , Murray D. W.
Published: March 2013

There is conflicting evidence about the merits of mobile bearings in total knee replacement, partly because most randomised controlled trials (RCTs) have not been adequately powered. We report the results of a multicentre RCT of mobile versus fixed bearings. This was part of the knee arthroplasty trial (KAT), where 539 patients were randomly allocated to mobile or fixed bearings and analysed on an intention-to-treat basis. The primary outcome measure was the Oxford Knee Score (OKS) plus secondary measures including Short Form-12, EuroQol EQ-5D, costs, cost-effectiveness and need for further surgery.

There was no significant difference between the groups pre-operatively: mean OKS was 17.18 (sd 7.60) in the mobile-bearing group and 16.49 (sd 7.40) in the fixed-bearing group. At five years mean OKS was 33.19 (sd 16.68) and 33.65 (sd 9.68), respectively. There was no significant difference between trial groups in OKS at five years (-1.12 (95% confidence interval -2.77 to 0.52) or any of the other outcome measures. Furthermore, there was no significant difference in the proportion of patients with knee-related re-operations or in total costs.

In this appropriately powered RCT, over the first five years after total knee replacement functional outcomes, re-operation rates and healthcare costs appear to be the same irrespective of whether a mobile or fixed bearing is used.

Cite this article: Bone Joint J 2013;95-B:486–92.
Long-term (ten- to 15-year) outcome of arthroscopically assisted Elmslie-Trillat tibial tubercle osteotomy
Authors: Naveed M. A. , Ackroyd C. E. , Porteous A. J.
Published: March 2013

We present the ten- to 15-year follow-up of 31 patients (34 knees), who underwent an Elmslie-Trillat tibial tubercle osteotomy for chronic, severe patellar instability, unresponsive to non-operative treatment. The mean age of the patients at the time of surgery was 31 years (18 to 46) and they were reviewed post-operatively, at four years (2 to 8) and then at 12 years (10 to 15). All patients had pre-operative knee radiographs and Cox and Insall knee scores. Superolateral portal arthroscopy was performed per-operatively to document chondral damage and after the osteotomy to assess the stability of the patellofemoral joint. A total of 28 knees (82%) had a varying degree of damage to the articular surface. At final follow-up 25 patients (28 knees) were available for review and underwent clinical examination, radiographs of the knee, and Cox and Insall scoring. Six patients who had no arthroscopic chondral abnormality showed no or only early signs of osteoarthritis on final radiographs; while 12 patients with lower grade chondral damage (grade 1 to 2) showed early to moderate signs of osteoarthritis and six out of ten knees with higher grade chondral damage (grade 3 to 4) showed marked evidence of osteoarthritis; four of these had undergone a knee replacement. In the 22 patients (24 knees) with complete follow-up, 19 knees (79.2%) were reported to have a good or excellent outcome at four years, while 15 knees (62.5%) were reported to have the same at long-term follow-up. The functional and radiological results show that the extent of pre-operatively sustained chondral damage is directly related to the subsequent development of patellofemoral osteoarthritis.

Cite this article: Bone Joint J 2013;95-B:478–85.
Radiological findings that may indicate a prior silent slipped capital femoral epiphysis in a cohort of 2072 young adults
Authors: Lehmann T. G. , Engesæter I. Ø. , Laborie L. B. , Lie S. A. , Rosendahl K. , Engesæter L. B.
Published: March 2013

The reported prevalence of an asymptomatic slip of the contralateral hip in patients operated on for unilateral slipped capital femoral epiphysis (SCFE) is as high as 40%. Based on a population-based cohort of 2072 healthy adolescents (58% women) we report on radiological and clinical findings suggestive of a possible previous SCFE. Common threshold values for Southwick’s lateral head–shaft angle (≥ 13°) and Murray’s tilt index (≥ 1.35) were used. New reference intervals for these measurements at skeletal maturity are also presented.

At follow-up the mean age of the patients was 18.6 years (17.2 to 20.1). All answered two questionnaires, had a clinical examination and two hip radiographs.

There was an association between a high head–shaft angle and clinical findings associated with SCFE, such as reduced internal rotation and increased external rotation. Also, 6.6% of the cohort had Southwick’s lateral head–shaft angle ≥ 13°, suggestive of a possible slip. Murray’s tilt index ≥ 1.35 was demonstrated in 13.1% of the cohort, predominantly in men, in whom this finding was associated with other radiological findings such as pistol-grip deformity or focal prominence of the femoral neck, but no clinical findings suggestive of SCFE.

This study indicates that 6.6% of young adults have radiological findings consistent with a prior SCFE, which seems to be more common than previously reported.

Cite this article: Bone Joint J 2013;95-B:452–8.
Synovial fluid white cell and differential count in the diagnosis or exclusion of prosthetic joint infection
Authors: Dinneen A. , Guyot A. , Clements J. , Bradley N.
Published: March 2013

Cut-off values with highest sensitivity and specificity for the synovial fluid white cell and differential count will facilitate the accurate diagnosis of infection in total knee (TKR) and total hip replacement (THR). All patients undergoing revision TKR or THR for suspected prosthetic joint infection between 2009 and 2011 at two hospitals were identified. A total of 75 patients were included with a mean age of 70.3 years (38 to 89). Synovial fluid was aspirated pre-operatively and peri-prosthetic tissue samples were taken intra-operatively for histological and microbiological examination.

Receiver operating characteristic (ROC) plots were constructed for white cell and differential counts in aspirated fluid. The optimal cut-off for TKR and THR was 1590 white cells/µl and 65% neutrophilia. The white cell count cut-off value identified for THR was notably lower than previously quoted in the literature. A cut-off value for white cell count in synovial aspirate in suspected prosthetic joint infection of between 1100 and 1700 white cells/µl is likely to be applicable to both THR and TKR.

Cite this article: Bone Joint J 2013;95-B:554–7.
Teres major tendon transfer for patients with massive irreparable posterosuperior rotator cuff tears
Authors: Henseler J. F. , Nagels J. , van der Zwaal P. , Nelissen R. G. H. H.
Published: March 2013

Surgical repair of posterosuperior rotator cuff tears has a poorer outcome and a higher rate of failure compared with repairs of supraspinatus tears. In this prospective cohort study 28 consecutive patients with an irreparable posterosuperior rotator cuff tear after failed conservative or surgical treatment underwent teres major tendon transfer. Their mean age was 60 years (48 to 71) and the mean follow-up was 25 months (12 to 80). The mean active abduction improved from 79° (0° to 150°) pre-operatively to 105° (20° to 180°) post-operatively (p = 0.011). The mean active external rotation in 90° abduction improved from 25° (0° to 70°) pre-operatively to 55° (0° to 90°) post-operatively (p < 0.001). The mean Constant score improved from 43 (18 to 78) pre-operatively to 65 (30 to 86) post-operatively (p < 0.001). The median post-operative VAS (0 to 100) for pain decreased from 63 (0 to 96) pre-operatively to 5 (0 to 56) post-operatively (p < 0.001).

In conclusion, teres major transfer effectively restores function and relieves pain in patients with irreparable posterosuperior rotator cuff tears and leads to an overall clinical improvement in a relatively young and active patient group with limited treatment options.

Cite this article: Bone Joint J 2013;95-B:523–9.
Scapular notching and osteophyte formation after reverse shoulder replacement
Authors: Roche C. P. , Marczuk Y. , Wright T. W. , Flurin P-H. , Grey S. , Jones R. , Routman H. D. , Gilot G. , Zuckerman J. D.
Published: March 2013

This study provides recommendations on the position of the implant in reverse shoulder replacement in order to minimise scapular notching and osteophyte formation. Radiographs from 151 patients who underwent primary reverse shoulder replacement with a single prosthesis were analysed at a mean follow-up of 28.3 months (24 to 44) for notching, osteophytes, the position of the glenoid baseplate, the overhang of the glenosphere, and the prosthesis scapular neck angle (PSNA).

A total of 20 patients (13.2%) had a notch (16 Grade 1 and four Grade 2) and 47 (31.1%) had an osteophyte. In patients without either notching or an osteophyte the baseplate was found to be positioned lower on the glenoid, with greater overhang of the glenosphere and a lower PSNA than those with notching and an osteophyte. Female patients had a higher rate of notching than males (13.3% vs 13.0%) but a lower rate of osteophyte formation (22.9% vs 50.0%), even though the baseplate was positioned significantly lower on the glenoid in females (p = 0.009) and each had a similar mean overhang of the glenosphere.

Based on these findings we make recommendations on the placement of the implant in both male and female patients to avoid notching and osteophyte formation.

Cite this article: Bone Joint J 2013;95-B:530–5.
Primary total hip replacement with a Furlong fully hydroxyapatite-coated titanium alloy femoral component
Authors: Sandiford N. , Doctor C. , Rajaratnam S. S. , Ahmed S. , East D. J. , Miles K. , Butler-Manuel A. , Shepperd J. A. N.
Published: March 2013

We present the extended follow-up (≥ 20 years) of a series of fully hydroxyapatite-coated femoral components used in 72 primary total hip replacements (THRs). Earlier results of this cohort have been previously published. All procedures were performed between 1986 and 1991. The series involved 45 women and 15 men with 12 bilateral procedures. Their mean age at the time of surgery was 60 years (46 to 80) and the mean duration of follow-up was 22.5 years (20 to 25). At final follow-up, the mean Merle d’Aubigné and Postel hip scores were 5.5 (4.5 to 6), 3.8 (3.5 to 5) and 3.3 (3.0 to 5.0) for pain, mobility and function, respectively. Of the patients 92% were very satisfied at the time of final follow-up.

There were seven revisions: six of the acetabular component for aseptic loosening and one of both the stem and the acetabular component for loosening due to deep infection. The survival of this prosthesis at 22.5 years with revision for any reason as the endpoint was 91.7% (95% confidence interval (CI) 84 to 99). Survival with aseptic loosening of the stem as the endpoint was 100% (95% CI 90 to 100).

This prosthesis provides pain relief in the long term. Survival of this component is comparable to the best results for primary THR with any means of fixation.

Cite this article: Bone Joint J 2013;95-B:467–71.
Lateral compartment osteoarthritis of the knee
Authors: Scott C. E. H. , Nutton R. W. , Biant L. C.
Published: March 2013

The lateral compartment is predominantly affected in approximately 10% of patients with osteoarthritis of the knee. The anatomy, kinematics and loading during movement differ considerably between medial and lateral compartments of the knee. This in the main explains the relative protection of the lateral compartment compared with the medial compartment in the development of osteoarthritis. The aetiology of lateral compartment osteoarthritis can be idiopathic, usually affecting the femur, or secondary to trauma commonly affecting the tibia. Surgical management of lateral compartment osteoarthritis can include osteotomy, unicompartmental knee replacement and total knee replacement. This review discusses the biomechanics, pathogenesis and development of lateral compartment osteoarthritis and its management.

Cite this article: Bone Joint J 2013;95-B:436–44.