bluuebunny/crossref_metadata_2025 huggingface dataset:
Control of Bacillus subtilis mtl operon expression by complex phosphorylation‐dependent regulation of the transcriptional activator MtlR
Authors: Joyet Philippe , Derkaoui Meriem , Poncet Sandrine , Deutscher Josef
Published: April 2010

Many bacteria transport mannitol via the mtlAF‐encoded phosphoenolpyruvate (PEP):carbohydrate phosphotransferase system (PTS). In most firmicutes the transcriptional activator MtlR controls expression of the mtl operon. MtlR possesses an N‐terminal DNA binding domain, two PTS regulation domains (PRDs), an EIIBGat‐ and EIIAMtl‐like domain. These four regulatory domains contain one or two potential PTS phosphorylation sites. Replacement of His‐342 or His‐399 in PRD2 with Ala prevented the phosphorylation of Bacillus subtilis MtlR by PEP, EI and HPr. These mutations as well as EI inactivation caused a loss of MtlR function in vivo. In contrast, phosphomimetic replacement of His‐342 with Asp rendered MtlR constitutively active. The absence of phosphorylation in PRD2 serves as catabolite repression mechanism. When EIIAMtl and the soluble EIIBMtl domain of the EIICBMtl permease were included in the phosphorylation mixture, His‐599 in the EIIA‐like domain of MtlR also became phosphorylated. Replacement of His‐599 with Asp rendered MtlR inactive, while His599Ala replacement caused slightly constitutive, glucose‐repressible MtlR activity. Doubly mutated His342Ala/His599Ala MtlR was still phosphorylated by EI, HPr and EIIAMtl at Cys‐419 in the EIIBGat‐like domain. Cys419Ala replacement and deletion of EIIAMtl caused strong constitutive glucose‐repressible MtlR activity. This is the first report that Cys phosphorylation controls PRD‐containing transcriptional activators.
SecA: a tale of two protomers
Authors: Sardis Marios Frantzeskos , Economou Anastassios
Published: April 2010

Bacteria, Archaea and Eukaryotes have evolved a plethora of mechanisms to translocate proteins across their various membranes. The bacterial Sec pathway is ubiquitous and essential for cell viability and is used by most proteins destined for the inner membrane, the periplasm or beyond. In bacteria, Sec system components include the heterotrimers SecY/SecE/SecG and SecD/SecF/YajC and the peripherally associated ATPase motor SecA. SecA in solution is mainly dimeric. Unexpectedly, structures of SecA dimers from different or even the same bacterium do not have a consistent dimerization interface. Analysis of the functional assembled translocase complexes blurs the picture even further as the functional quaternary state of the SecYEG channel is also disputed. Several experimental approaches tried to define the oligomeric state of SecA during preprotein ‘pushing’ through SecYEG. One high‐resolution SecA–SecYEG complex has been visualized. This snapshot might be a step closer to the actual translocating machinery. Nevertheless, because of the use of detergent, the true quartenary state of the translocase might have been disturbed. Hence, even after this and other studies, several issues remain puzzling. New approaches must be combined with current tools to gain insight into the functionally relevant quartenary states of SecA and SecYEG during preprotein translocation.
Genetic diversity of weedy red rice (Oryza sativa) in Arkansas, USA
Authors: SHIVRAIN V K , BURGOS N R , AGRAMA H A , LAWTON‐RAUH A , LU B , SALES M A , BOYETT V , GEALY D R , MOLDENHAUER K A K
Published: April 2010

Shivrain VK, Burgos NR, Agrama HA, Lawton‐Rauh A, Lu B, Sales MA, Boyett V, Gealy DR & Moldenhauer KAK (2010). Genetic diversity of weedy red rice (Oryza sativa) in Arkansas, USA. Weed Research50, 289–302.

Weedy red rice (Oryza sativa) is a problematic weed in cultivated rice. About 50% of US rice is produced in Arkansas and 60% of these fields have some red rice infestation. Red rice populations are morphologically and phenologically diverse. We hypothesise that red rice in Arkansas has high genetic diversity, which underlies its wide phenotypic diversity, and that some alleles from cultivated rice have been introgressed into red rice during more than a century of coexistence. We tested 137 red rice accessions from four ecological zones in Arkansas and 36 cultivars that have been grown in Arkansas in the past century. Twenty‐seven rice microsatellite primers, distributed across 12 chromosomes, were used to generate molecular markers. The overall Nei’s genetic distance (GD) of red rice accessions was 0.70. Rice grown in the last century had an overall GD of 0.26. The awnless strawhull red rice was genetically distant from blackhull (GD = 0.55) and brownhull (GD = 0.60) red rice types. Nei’s GD between blackhull and brownhull red rice was 0.42. Brownhull and blackhull formed one genotypic cluster, whereas the majority of strawhull red rice formed another cluster. Within blackhull red rice, the GD was 0.76, whereas for awnless strawhull it was 0.68, 0.75 for awned strawhull and 0.80 for brownhull types. The gene diversity of blackhull and strawhull correlated with zone of origin. A quarter of the red rice accessions share common alleles with cultivated rice. A diverse complex of weedy populations has evolved in a region devoid of other weedy and wild Oryza species.
Definitions of hypotension after spinal anaesthesia for caesarean section: literature search and application to parturients
Authors: KlÖHR S. , ROTH R. , HOFMANN T. , ROSSAINT R. , HEESEN M.
Published: April 2010

Background: Spinal anaesthesia for caesarean section may cause hypotension, jeopardizing the foetus and its mother. We aimed to identify the spectrum of definitions of hypotension used in the scientific literature. In a second part, we applied these definitions to a prospective cohort in order to evaluate the effect of different definitions on the incidence of hypotension.

Methods: A systematic literature search in PubMed was performed from 1999 to 2009 with the search terms ‘hypotension’ and ‘caesarean section’. Consecutive parturients undergoing caesarean section under spinal anaesthesia were included in a prospective study.

Results: Sixty‐three eligible publications (7120 patients) were retrieved, revealing 15 different definitions of hypotension. A decrease below 80% baseline and the combined definition of a blood pressure below 100 mmHg or a decrease below 80% baseline were the two most frequent definitions, found in 25.4% and 20.6% of the papers, respectively. When applying the spectrum of definitions to a prospective cohort, the incidences of hypotension varied between 7.4% and 74.1%. The incidence increased from 26.7% to 38.5% when using a value below 75% of baseline instead of below 70% of baseline.

Conclusion: There is not one accepted definition of hypotension in the scientific literature. The incidence of hypotension varies depending on the chosen definition. Even minor changes of the definition cause major differences in the frequency of hypotension. This makes it difficult to compare studies on interventions to treat/prevent hypotension and probably hampers progress in this area of research.
Stuck long‐term indwelling central venous catheters in adolescents: three cases and a short topical review
Authors: MORTENSEN A. , AFSHARI A. , HENNEBERG S. W. , HANSEN M. A.
Published: April 2010

We present three cases of fixated vascular injection ports. Two patients had cystic fibrosis and one had an immunological defect. All catheters were made from polyurethane and implanted in adolescent patients. Indwelling time were 6–8 years. One patient's catheter was entirely integrated in the vessel wall and impossible to remove. In the other two cases, catheters were removed with great difficulty by the interventional radiologists. These cases raise important questions concerning the maximum indwelling time and the choice of catheter material when implanting permanent central venous catheters (CVCs) in adolescents. Furthermore, it highlights the importance of not breaking a CVC in the attempt to remove it.
Sex‐specific heritability of cell‐mediated immune response in the blue tit nestlings (Cyanistes caeruleus)
Authors: DROBNIAK S. M. , WIEJACZKA D. , ARCT A. , DUBIEC A. , GUSTAFSSON L. , CICHOŃ M.
Published: April 2010

Here, we aimed at estimating sex‐specific heritabilities of cell‐mediated immune response (CMI) in the blue tit nestlings (Cyanistes caeruleus). To separate genetic and environmental components of the phenotypic variance in CMI (measured using phytohaemagglutinin assay), we performed a cross‐fostering experiment. Additionally, controlled environmental variation was introduced by enlarging some broods. Our analyses revealed a significant genetic component (as approximated by the nest‐of‐origin term) of the phenotypic variance in immune response. More importantly, these genetic effects differed between sexes and experimentally manipulated brood sizes, as indicated by significant genotype‐by‐sex and genotype‐by‐environment interactions. We discuss possible causes of such sexual dimorphism in gene expression and suggest that sex‐ and environment‐specific genetic interactions may contribute to the maintenance of genetic variability in traits related to immune functions.
Interaction between female mating preferences and predation may explain the maintenance of rare males in the pentamorphic fish Poecilia parae
Authors: HURTADO‐GONZALES J. L. , BALDASSARRE D. T. , UY J. A. C.
Published: April 2010

Variation in mating preferences coupled with selective predation may allow for the maintenance of alternative mating strategies. Males of the South American live‐bearing fish Poecilia parae fall in one of five discrete morphs: red, yellow, blue, stripe‐coloured tail (parae) and female mimic (immaculata). Field surveys indicate that the red and yellow morphs are the rarest and that their rarity is consistent across years. We explored the role of variable female mating preference and selective predation by visual predators in explaining the rarity of red and yellow males, and more generally, the maintenance of this extreme colour polymorphism. We presented wild‐caught P. parae females and Aequidens tetramerus, the most common cichlid predator, with the five male colour morphs in separate trials to determine mating and prey preferences, respectively. We found that a large proportion of females shared a strong preference for the rare carotenoid‐based red and yellow males, but a distinct group also preferred the blue and parae morphs. The cichlid predator strongly preferred red and yellow males as prey. Together, these results suggest that the interaction between premating sexual selection favouring and predation acting against the red and yellow morphs may explain their rarity in the wild. The trade‐off between sexual and natural selection, accompanied by variation in female mating preferences, may therefore facilitate the maintenance of the striking colour polymorphism in P. parae.
Environmental and not maternal effects determine variation in offspring phenotypes in a passerine bird
Authors: MAINWARING M. C. , DICKENS M. , HARTLEY I. R.
Published: April 2010

Maternal and environmental effects can profoundly influence offspring phenotypes, independent of genetic effects. Within avian broods, both the asymmetric post‐hatching environment created by hatching asynchrony and the differential maternal investment through the laying sequence have important consequences for individual nestlings in terms of the allocation of resources to body structures with different contributions to fitness. The purpose of this study was to evaluate the relative importance of post‐hatching environmental and maternal effects in generating variation in offspring phenotypes. First, an observational study showed that within blue tit,Cyanistes caeruleus, broods, late‐hatched nestlings allocated resources to tarsus development, maintained mass gain and head‐bill growth and directed resources away from the development of fourth primary feathers. Second, a hatching order manipulation experiment resulted in nestlings from first‐laid eggs hatching last, thereby allowing comparison with both late and early‐hatched nestlings. Experimental nestlings had growth patterns which were closer to late‐hatched nestlings, suggesting that within‐brood growth patterns are determined by post‐hatching environmental effects. Therefore, we conclude that post‐hatching environmental effects play an important role in generating variation in offspring phenotypes.
Ancestral polymorphism in exon 2 of bluethroat (Luscinia svecica) MHC class II B genes
Authors: ANMARKRUD J. A. , JOHNSEN A. , BACHMANN L. , LIFJELD J. T.
Published: April 2010

The genes of the major histocompatibility complex (MHC) are important model genes for understanding selective forces in evolution. Here, we document, using a cloning and sequencing approach, high polymorphism at the exon 2 of the MHC class II B (MHCIIB) genes in the bluethroat (Luscinia svecica); a minimum of 61 unique alleles were detected in 20 individuals, and at least 11 functional loci. In addition, several pseudogenes were revealed. The specimens originated from three different bluethroat subspecies (azuricollis, cyanecula and svecica), and we also analysed four specimens of the closely related thrush nightingale (L. luscinia) for comparison. Phylogenetic analyses of the functional alleles revealed 258 equally parsimonious trees with poor statistical support for the majority of nodes. The distribution of the sequences in the trees point to an ancestral origin of the polymorphism in MHC class II B genes, a portion of which predated the phylogenetic split between the bluethroat and the thrush nightingale. Strong signatures of balancing selection were uncovered for the codons coding for the peptide‐binding residues of the functional MHCIIB exon 2 alleles. Our results highlight the importance of duplication and recombination events for shaping passerine MHC and give insights in the evolutionary dynamics of MHC variation among closely related taxa.
Geological and mineralogical study of eclogite and glaucophane schists in the Naga Hills Ophiolite, Northeast India
Authors: Ghose Naresh C. , Agrawal Om Prakash , Chatterjee Nilanjan
Published: April 2010

A variety of low‐ to high‐pressure metamorphic assemblages occur in the metabasic rocks and metachert in the Upper Cretaceous–Eocene ophiolite belt of the central part of the Naga Hills, an area in the northern sector of the Indo–Myanmar Ranges in the Indo–Eurasian collision zone. The ophiolite suite includes peridotite tectonite containing garnet lherzolite xenoliths, layered ultramafic–mafic cumulates, metabasic rocks, basaltic lava, volcaniclastics, plagiogranite, and pelagic sediments emplaced as dismembered and imbricated bodies at thrust contacts between moderately metamorphosed accretionary rocks/basement (Nimi Formation/Naga Metamorphics) and marine sediments (Disang Flysch). It is overlain by coarse clastic Paleogene sediments of ophiolite‐derived rocks (Jopi/Phokphur Formation). The metabasic rocks, including high‐grade barroisite/glaucophane‐bearing epidote eclogite and glaucophane schist, and low‐grade greenschist and prehnite–clinochlore schist, are associated with lava flows and ultramafic cumulates at the western thrust contact. Chemically, the metabasites show a low‐K tholeiitic affinity that favors derivation from a depleted mantle source as in the case of mid‐ocean ridge basalt. Thermobarometry indicates peakP–Tconditions of about 20 kb and 525°C. Retrogression related to uplift is marked by replacement of barroisite and omphacite by glaucophane followed by secondary actinolite, albite, and chlorite formation. A metabasic lens with an eclogite core surrounded by successive layers of glaucophane schist and greenschist provides field evidence of retrogression and uplift. Presence of S‐C mylonite in garnet lherzolite and ‘mica fish’ in glaucophane schist indicates ductile deformation in the shear zone along which the ophiolite was emplaced.
Restriction–modification systems may be associated with Helicobacter pylori virulence
Authors: Ando Takafumi , Ishiguro Kazuhiro , Watanabe Osamu , Miyake Nobuyuki , Kato Tsuyoshi , Hibi Satoshi , Mimura Shunya , Nakamura Masanao , Miyahara Ryoji , Ohmiya Naoki , Niwa Yasumasa , Goto Hidemi
Published: April 2010

Restriction–modification (R‐M) systems are exclusive to unicellular organisms and ubiquitous in the bacterial world. Bacteria use R‐M systems as a defense against invasion by foreign DNA. Analysis of the genome sequences of Helicobacter pylori strains 26 695 and J99 identified an extraordinary number of genes with homology to R‐M genes in other bacterial species. All H. pylori strains possess their own unique complement of active R‐M systems. All of the methylases that have been studied so far were present in all major human population groupings, suggesting that their horizontal acquisition pre‐dated the separation of these populations. The two most strongly conserved methylase genes of H. pylori, hpy IM and hpy IIIM, are both preceded by alternative genes that compete for presence at their loci, and furthermore these genes may be associated with H. pylori pathogenicity. Further study should investigate the roles of H. pylori R‐M systems.
Protective effect of roxatidine against indomethacin‐induced small intestinal mucosal injury in rats
Authors: Umegaki Eiji , Yoda Yukiko , Tokioka Satoshi , Murano Mitsuyuki , Higuchi Kazuhide
Published: April 2010

Background and Aims:  Non‐steroidal anti‐inflammatory drugs (NSAIDs) are among the most significant causative factors of gastroduodenal ulcers. Recent reports have demonstrated that NSAIDs can also frequently induce ulceration and erosions of the small intestine. The aim of this study was to examine whether or not roxatidine (an H2 receptor antagonist), which is known to increase gastric mucus in addition to inhibiting gastric acid, might suppress indomethacin‐induced small intestinal mucosal injury, through an increase in mucus in rats.

Methods:  Rats were given two p.o. doses of roxatidine, famotidine or cimetidine before and after the s.c. indomethacin injection. The injured area of the small intestine was analyzed. To examine effects of drugs on small intestinal mucus, rats were also given two p.o. doses of roxatidine, famotidine or cimetidine, and the ratio of the periodic acid Schiff (PAS)‐positive area to the area of the mucosa in the small intestine was analyzed. In addition, we evaluated the involvement of nitric oxide (NO) and prostaglandins (PG) in the effect of roxatidine on small intestinal mucus.

Results:  Roxatidine significantly ameliorated indomethacin‐induced small intestinal injury and increased the PAS‐stained areas in the small intestinal mucosa, while cimetidine and famotidine had no significant effect. Pretreatment with N‐nitro‐L‐arginine methyl ester but not with indomethacin, suppressed the effect of roxatidine on small intestinal mucus, suggesting that the effect is mediated by endogenous NO but not by PG.

Conclusion:  Roxatidine suppressed indomethacin‐induced small intestinal injury in rats. One possible mechanism is an increase of small intestinal mucus, mediated by NO.
Identification of inflammation‐related proteins in a murine colitis model by 2D fluorescence difference gel electrophoresis and mass spectrometry
Authors: Naito Yuji , Takagi Tomohisa , Okada Hitomi , Omatsu Tatsushi , Mizushima Katsura , Handa Osamu , Kokura Satoshi , Ichikawa Hiroshi , Fujiwake Hideshi , Yoshikawa Toshikazu
Published: April 2010

Background and Aims:  The aim of this study was to identify new intestinal proteins potentially associated with acute inflammation using proteomic profiling of an in vivo mice model of ulcerative colitis.

Methods:  2D fluorescence difference gel electrophoresis (2D‐DIGE) and matrix‐assisted laser desorption/ionization time‐of‐flight spectrometer (MALDI‐TOF) peptide mass fingerprinting were used to determine differentially expressed proteins between normal and inflamed intestinal mucosa. Acute colitis was induced by 8.0% dextran sodium sulfate (DSS) given p.o. for 7 days.

Results:  Among a total of seven protein spots showing differential expression, we identified five different proteins, of which two were upregulated and three downregulated in colitis in comparison to normal mucosa, using the MASCOT search engine. 3‐Hydroxy‐3‐methylglutaryl‐coenzyme A synthase 2 and serpin b1a were upregulated proteins, and protein disulfide‐isomerase A3, peroxiredoxin‐6 and vimentin were identified as downregulated proteins.

Conclusion:  These identified proteins may be responsible for the development of the intestinal inflammation. 2D‐DIGE and MALDI‐TOF mass spectrometry are useful in the search for the differentially expressed proteins.
Contribution of efflux pumps to clarithromycin resistance in Helicobacter pylori
Authors: Hirata Kenro , Suzuki Hidekazu , Nishizawa Toshihiro , Tsugawa Hitoshi , Muraoka Hiroe , Saito Yoshimasa , Matsuzaki Juntaro , Hibi Toshifumi
Published: April 2010

Background and Aims:  Although clarithromycin (CLR) is one of the most commonly recommended component drugs of Helicobacter pylori eradication regimens, the prevalence of CLR‐resistant H. pylori has been increasing. It is well known that CLR resistance is associated with point mutations in 23S rRNA, but an active multidrug efflux mechanism of H. pylori may also play a role in its drug resistance. At least four gene clusters have been identified as efflux pump systems in H. pylori and the present study was designed to investigate their role in the CLR resistance of clinical isolates of H. pylori.

Methods:  Fifteen CLR‐resistant H. pylori strains (minimal inhibitory concentration [MIC]≥ 1 µg/mL) isolated from patients at Keio University Hospital were examined for expression of efflux pump mRNA by real‐time polymerase chain reaction. In addition, the MIC of CLR in the presence or absence of Phe‐Arg‐β‐naphthylamide (PAβN), an efflux pump inhibitor (EPI), were determined.

Results:  In all 15 strains, efflux pump mRNA was expressed, and the MIC of CLR were decreased by using EPI, despite possessing 23s rRNA point mutations. In addition, the MIC of CLR was decreased by the EPI in a concentration‐dependent fashion.

Conclusion:  The efflux pump of H. pylori is associated with the development of resistance to CLR, in addition to 23S rRNA point mutations. Efflux pumps could be a novel target for reversing drug resistance in H. pylori.
Serological analysis of Helicobacter hepaticus infection in patients with biliary and pancreatic diseases
Authors: Shimoyama Tadashi , Takahashi Ryoki , Abe Daijiro , Mizuki Ichiro , Endo Tetsu , Fukuda Shinsaku
Published: April 2010

Background and Aims:  Infection with Helicobacter hepaticus has been associated with development of hepatocellular carcinoma and gallstones in animal models. In humans, however, the association of H. hepaticus infection with biliary and pancreatic diseases has not been elucidated. The aim of this study was to serologically examine the prevalence of H. hepaticus infection in patients with biliary and pancreatic diseases.

Methods:  Serum samples obtained from 55 patients with cholelithiasis, 18 with bile duct or gallbladder cancer and 19 with pancreatic cancer were studied. Sera were obtained from 34 control subjects who underwent endoscopy and were diagnosed as not having peptic ulcers or cancers. Seropositivity of H. hepaticus was examined by western blot analysis using a H. hepaticus‐specific antigen. To validate the specificity, positive sera were also tested after absorption with H. hepaticus whole‐cell sonicate. Serum samples were also tested for the presence of anti‐Helicobacter pylori antibody.

Results:  Prevalence of antibody to H. hepaticus‐specific antigen in patients with bile tract cancer was 38.8% and was significantly higher than in control subjects (13.1%, P < 0.05). Prevalence of antibody to H. hepaticus‐specific antigen was 18.2% and 10.5% in patients with cholelithiasis and pancreatic cancer, respectively. Seropositivity for H. pylori was similar in all groups. Detection of the H. hepaticus‐specific band was significantly decreased after the sera were absorbed with H. hepaticus whole‐cell sonicate.

Conclusion:  Infection with H. hepaticus might be associated with bile duct cancer. Results obtained from absorbed sera suggested high specificity of the western blot analysis.
Efficacy of antibiotic combination therapy in patients with active ulcerative colitis, including refractory or steroid‐dependent cases
Authors: Uehara Toshiki , Kato Kimitoshi , Ohkusa Toshifumi , Sugitani Masahiko , Ishii Yukimoto , Nemoto Norimichi , Moriyama Mitsuhiko
Published: April 2010

Background and Aims:  We previously demonstrated that antibiotic combination therapy is effective for induction and maintenance of ulcerative colitis (UC) remission. Herein, we assessed whether antibiotic combination therapy is effective for active UC, including cases with steroid refractory or dependent disease.

Methods:  We enrolled 25 patients with active UC including 17 steroid‐dependent or refractory cases. These patients received amoxicillin 500 mg t.i.d., tetracycline 500 mg t.i.d. and metronidazole 250 mg t.i.d. for 2 weeks as well as conventional treatment. Seven colonic segments from the appendiceal region to the rectum were scored for endoscopic activity and histology. Clinical activity indexes (CAI) were also determined.

Results:  At 3 and 12 months after antibiotic treatment, CAI and endoscopic score were significantly decreased as compared to those before treatment (P < 0.001 and P < 0.05, P < 0.01, respectively). Histological scores were also significantly decreased at 12 months as compared to before treatment (P < 0.01). The clinical response rates in steroid‐dependent patients were 60% and 73.3% at 3 and 12 months, respectively, while being 50% at 12 months in steroid‐refractory patients. Among the 17 steroid‐dependent or refractory patients, 12 (70.6%) were able to discontinue steroid therapy at 12 months. No serious drug‐related toxicities were observed during the trial.

Conclusion:  This long‐term follow‐up study suggests 2‐week antibiotic combination therapy to be effective and safe in patients with active UC including those with steroid‐refractory or dependent disease.
Colonoscopic differences of erosive and/or small ulcerative lesions for diagnosis of colonic inflammatory diseases
Authors: Inoue Takuya , Murano Mitsuyuki , Abe Yosuke , Morita Eijiro , Murano Naoko , Toshina Ken , Umegaki Eiji , Hirata Ichiro , Higuchi Kazuhide
Published: April 2010

Background and Aims:  Various etiologies and diseases may be related to erosive and/or small ulcerative lesions without gross appearance in the colon during colonoscopy. However, few investigators report on differential diagnosis of colonic inflammatory diseases. Thus, we investigated the clinical significance of these lesions and the value of colonoscopy in the differential diagnosis of colitis.

Methods:  In 110 patients with erosive and/or small ulcerative lesions (<5 mm) who were treated in our hospital during the past 9 years, we retrospectively investigated the relationship between endoscopic morphology and clinical diagnosis. The intestinal lesions were endoscopically classified into three groups (A, hyperemic type; B, aphthous type; and C, verrucous type).

Results:  The lesions were mainly located in the rectum to the sigmoid colon in group A. In group C, the lesions were most frequently located in the transverse colon and deeper areas. Endoscopically, the etiology was unclear in 74.5% of group A and 73.8% of group B, however, in group C, most of them (81.0%) were associated with specific diseases. With respect to inflammatory bowel diseases, 71.4% of the patients with Crohn's disease and all patients with ulcerative colitis were assigned to group A or B.

Conclusion:  Erosive and/or small ulcerative lesions belonging to group A or B were mainly non‐specific. However, careful follow up was required in groups A and B, which included the possibility of inflammatory bowel diseases, when the symptoms or lesions were not improved.
Homology model of the DNA gyrase enzyme of Helicobacter pylori, a target of quinolone‐based eradication therapy
Authors: Matsuzaki Juntaro , Suzuki Hidekazu , Tsugawa Hitoshi , Nishizawa Toshihiro , Hibi Toshifumi
Published: April 2010

Background and Aims:  Resistance of Helicobacter pylori to the standard therapeutic antimicrobial agents has been demonstrated. Although quinolones are an alternative candidate for third‐line eradication therapy, quinolone resistance of H. pylori is also increasing. Quinolone resistance of H. pylori is caused by a point mutation of the DNA gyrase subunit A (GyrA) protein, especially on amino acids 87 and 91. The aim of this study is to surmise the structure of H. pylori GryA.

Methods:  The modeling of the 3‐D structure of H. pylori GyrA was performed by an automated homology modeling program: SWISS‐MODEL. The position of amino acids 87 and 91 in H. pylori GyrA was plotted on the homology model. To estimate the function of quinolone resistance‐determining region (QRDR), the structure of H. pylori GyrA was compared with Escherichia coli GyrA.

Results:  A molecular model of H. pylori GyrA could be predicted using SWISS‐MODEL. The GyrA N‐ and C‐terminal domains closely resembled those of E. coli. The position of amino acids 87 and 91 in H. pylori GyrA was part of the DNA binding region (head dimer interface) on the GyrA N‐terminal domain.

Conclusion:  Our homology model of H. pylori GryA suggests that the quinolone resistance‐determining region is on the head dimer interface of the GyrA N‐terminal domain.
Asthma and insulin resistance in children
Authors: ARSHI Mandana , CARDINAL John , HILL Rebecca J. , DAVIES Peter S.W. , WAINWRIGHT Claire
Published: April 2010

Background and objective: Increased BMI is a risk factor for asthma in children and may be related to adipokines. Adipokines affect insulin‐stimulated glucose uptakein vitrobut, to date there is little evidence for such a rolein vivo. We explored relationships between obesity and allergic asthma in children.

Methods: Twenty‐one allergic asthmatics (AA) and 10 non‐allergic healthy controls, aged 6–17.9 years were studied. AA group included children with a positive mannitol challenge test, >25 ppb of exhaled nitric oxide and a positive skin prick test. BMIz‐scores were calculated. Blood levels of insulin, glucose, leptin, resistin, tumour necrosis factor‐α, IL‐4, IL‐5 and IL‐6 were measured. Insulin resistance (IR) was estimated using the homeostasis model assessment (HOMA).

Results: There was no significant difference in BMIz‐scores between AA and healthy controls (mean: 0.01 vs −0.10). However, significant differences were found in the blood levels of IL‐6 (P = 0.05), IL‐4 (P = 0.04), IL‐5 (P = 0.01) and leptin (P = 0.02). IR was only found in the AA group (42.85%). Homeostasis model assessment insulin resistance (HOMA‐IR) was significantly related to IL‐6 (r = 0.44,P = 0.05) and tumour necrosis factor‐α (r = −0.45,P = 0.05).

Conclusions: IR was observed in AA. Our findings are suggestive of a complex interaction between the inflammatory state and adiposity, allergy and asthma.
Robotic‐assisted laparoscopic radical prostatectomy: Learning curve of first 100 cases
Authors: Ou Yen Chuan , Yang Chi Rei , Wang John , Cheng Chen Li , Patel Vipul R
Published: April 2010

Objective:  Robotic‐assisted laparoscopic radical prostatectomy (RALP) is gaining popularity for treating localized prostate cancer. We aimed to analyze the learning curve of a single surgeon using RALP in Taiwan.

Methods:  Medical records of 100 consecutive patients who underwent RALP were retrospectively reviewed. Preoperative, perioperative and postoperative parameters between patients in the first 30 cases (Group I), the second 30 cases (Group II) and cases 61–100 (Group III) undergoing RALP were analyzed.

Results:  Console time was shorter and blood loss was reduced in Groups II and III compared with Group I. Significant differences were found in vesicourethral anastomosis time (46.38 min for Group I vs 31.0 min for Group II vs 27 min for Group III, P < 0.01). Postoperative stay became statistically significantly shorter, from 7.33 days for Group I to 3.93 days for Group II to 3.0 days for Group III. Positive surgical margin of pT2 was reduced (13.3% for Group I, 7.1% for Group II and 0% for Group III) but not of pT3 (86.7% for Group I, 75% for Group II and 62.9% for Group III). Continence rate at 3 months was higher in Groups II (95%) and III (96.6%) than in Group 1 (76.7%, P < 0.05).

Conclusions:  For every 30 cases of RALP, vesicourethral anastomosis time and postoperative stay were significantly shorter. However, the incidence of surgical margin in pT3 prostate cancer was not significantly reduced. A learning curve of more than 100 cases is required to decrease the positive surgical margin in pT3 tumors.
Utilization of therapeutic intervention to prevent mother to child transmission of HIV in a teaching hospital in Kolkata, India
Authors: Chaudhuri Snehamay , Mundle Malay , Konar Hiralal , Das Chandana , Talukdar Arunansu , Ghosh Uday Sankar
Published: April 2010

Aim:  To assess the uptake of an HIV screening program and therapeutic intervention to minimize the risk of mother to child transmission.

Methods:  This was a cross‐sectional, observational study with retrospective data obtained from patient medical records. Pregnant women presenting to a tertiary care center in Kolkata, India, from 1 January 2004 – 31 December 2007 underwent HIV serology by rapid test after receiving group counseling. Care was administered using a standard national protocol by a multi‐disciplinary team of health‐care personnel. Main outcome measures were: acceptance of pretest counseling and HIV testing by pregnant women attending antenatal clinic services, post‐test counseling rate, coverage rate of nevirapine to mother–child pairs, and averted HIV infection in children.

Results:  Of the 52 127 new antenatal booking visits, 49 580 (95.11%) women attended pretest counseling and 47 506 (91.13%) women accepted HIV testing. Eighty‐six women were found to be seropositive. The seroprevalence rate of HIV infection was 0.17%. Thirty‐seven mothers (88%) and all newborn infants (100%) had received nevirapine prophylaxis. Overall nevirapine coverage rate was 48%. Twenty‐four of the mother–infant pairs that we assessed had infants who were aged over 18 months by June 2008. Eleven (45.83%) of these women turned up with their babies for a blood test at 18 months. Three (27.27%) babies tested reactive.

Conclusion:  As uptake of testing is high and detection of HIV‐infected women in pregnancy remains very low, a radical rethinking of policies on therapeutic intervention and their implementation now needs to be undertaken.
Risk factors for term small for gestational age infants in women with low prepregnancy body mass index
Authors: Watanabe Hiroko , Inoue Kazuko , Doi Masako , Matsumoto Momoyo , Ogasawara Kayoko , Fukuoka Hideoki , Nagai Yasushi
Published: April 2010

Aim:  The purpose of our study was to investigate the association between low maternal prepregnancy body mass index (BMI) less than 18.5 kg/m2 and the incidence of small for gestational age (SGA) infants.

Material & Methods:  This was a cross‐sectional study. The women with BMI of less than 25.0 kg/m2 who gave birth to single term infants (37–42 weeks) at clinics and hospitals in the Tokyo metropolitan area between 2003 and 2004 were analyzed for risk factors for SGA.

Results:  Five hundred and seventy‐two women were underweight (BMI < 18.5 kg/m2) and 2708 (75.1%) were normal (18.5 ≤ BMI < 25.0 kg/m2). Birthweight, analyzed by multiple regression analysis, was highly related (P < 0.05) to gestational age, maternal age, parity, prepregnancy BMI, maternal weight gain and maternal smoking status. Women with a less than 9 kg weight during pregnancy were 1.8 times (confidence interval [CI], 1.6–2.2) more likely to give birth to an SGA infant compared with women who gained 9–12 kg. Maternal smoking more than 10 cigarettes per day was associated with an increased risk of having an SGA infant (odds ratio [OR], 2.5; CI, 1.8–3.5). Women with prepregnancy BMI less than 21.0 kg/m2 were associated with an increased risk of having an SGA infant (OR, 1.6; CI, 1.3–2.2 for BMI < 18.5 kg/m2, and OR, 1.4; CI, 1.2–1.7 for 18.5 ≤ BMI ≤ 21.0 kg/m2).

Conclusion:  We conclude that the detrimental effect of low prepregnancy BMI in Japanese women on birthweight and incidence of SGA infants. Our findings suggest that appropriate maternal BMI at conception followed by adequate weight gain during pregnancy may have a substantial influence on reducing the SGA infants and increasing the birthweight.
Scleroderma‐like cutaneous lesions induced by paclitaxel and carboplatin for ovarian carcinoma, not a single course of carboplatin, but re‐induced and worsened by previously administrated paclitaxel
Authors: Konishi Yoshitomo , Sato Hirokazu , Sato Naoki , Fujimoto Toshio , Fukuda Jun , Tanaka Toshinobu
Published: April 2010

Scleroderma‐like cutaneous lesion as an adverse event from paclitaxel and carboplatin has been reported. No report shows the occurrence of scleroderma‐like cutaneous lesions from a single course of carboplatin. The patient is a 67‐year‐old female, administered paclitaxel and carboplatin as neoadjuvant chemotherapy. Following four courses, scleroderma‐like cutaneous lesions were demonstrated. Skin biopsy corresponded to histopathological findings of scleroderma. Immunological investigation shows only antinuclear antibodies are positive. The characteristic Raynaud's phenomenon of scleroderma and hemorrhagic spots on the cuticles were not found. Postoperatively, a single course of carboplatin treatment was given. Scleroderma‐like cutaneous lesions re‐induced and worsened. This is the first report detailing scleroderma‐like cutaneous lesions induced by previously administrated paclitaxel that worsened by carboplatin.
Glu298Asp polymorphism of the endothelial nitric oxide synthase gene and plasma concentrations of asymmetric dimethylarginine in Turkish pre‐eclamptic women without fetal growth retardation
Authors: Turan Fahri , İlhan Necip , Kaman Dilara , Ateş Kadir , Kafkaslı Ayşe
Published: April 2010

Aims: Pre‐eclampsia (PE) is a leading cause of maternal death worldwide, affecting 3 to 5% of all pregnancies. We analyzed the Glu298Asp polymorphism of the endothelial nitric oxide synthase gene and asymmetric dimethylarginine (ADMA) in 55 Turkish patients with PE without fetal growth retardation (FGR) and in 54 healthy pregnant women.

Methods: Restriction fragment length polymorphism analysis of Glu298Asp of the endothelial nitric oxide synthase gene was evaluated by amplification of genomic DNA isolated from whole blood followed by digestion with the restriction enzyme Frio. PE was defined according to the Working Group2000criteria as high blood pressure (≥140/90 mmHg after 20 weeks of gestation) and proteinuria (>300 mg/24 h). We excluded the women with FGR Serum arginine, with only ADMA and symmetric dimethylarginine (SDMA) levels measured by high‐performance liquid chromatography.

Results: Genotypes were defined as GG, GT and TT according to the presence of the G and T alleles. In this case‐control study, we did not find any significant difference in either the genotypic distribution or allelic frequency of Glu298Asp gene polymorphism between the pre‐eclamptic patients and healthy pregnant women. Serum ADMA, arginine and SDMA levels were higher in patients with PE compared with healthy pregnant women (respectively,P < 0.0001,P < 0.0001,P < 0.0001).

Conclusions: The results suggested a lack of association between the Glu298Asp gene polymorphism and pre‐eclampsia without FGR in the Turkish population. But elevated ADMA and SDMA levels suggest that ADMA has a role in the pathogenesis of PE.
Comparison of clinical effects between total vaginal hysterectomy and total laparoscopic hysterectomy on large uteruses over 300 grams
Authors: Kim Hong‐Bae , Song Ji‐Eun , Kim Geun‐Hee , Cho Hye‐Yon , Lee Keun‐Young
Published: April 2010

Objective:  To compare intra‐ and postoperative complications, operation time, and duration of hospital stay, and to evaluate cost‐effectiveness between total vaginal hysterectomy (TVH) and total laparoscopic hysterectomy (TLH) groups.

Material & Methods:  Patients undergoing TVH or TLH for a large uterus weighing more than 300 g were recruited from January to December 2007: 150 cases of TVH and 100 cases of TLH, were used. Evaluated variables are as follows: age, parity, previous surgical history, intra‐ and postoperative complications, hysterectomy specimen weight, operation time, duration of hospital stay and total cost. Total cost ($US) include admission, anesthesia and operation costs.

Results:  There was no difference in demographics, intra‐ and postoperative complications, and uterine weight. However, operation time in TLH (mean, 179.9 min) was significantly longer than TVH (mean, 93.8 min; P < 0.05). The mean length of hospital stay was 6.13 days in TVH group and 5.78 days in TLH group, respectively (P < 0.05). TVH was more cost‐effective than TLH. There was significant difference in total cost between the two groups (TVH, mean $1815.7 vs TLH, mean $2560.5; P < 0.05). When the total cost was analyzed in detail, there was no difference in admission cost. However, the significant mean differences in anesthesia cost (TVH, $165 vs TLH, $245) and operation cost (TVH, $30.3 vs TLH, $768) were demonstrated (P < 0.05).

Conclusion:  TVH should not be abandoned for cases with a large uterus, and skilled surgeons for vaginal approach should preferentially perform TVH rather than TLH for the management of large uteruses.
Carcinosarcoma of the vulva: A case report
Authors: Loizzi Vera , Cormio Gennaro , Leone Luca , Scardigno Doriana , Carriero Carmine , Resta Leonardo , Selvaggi Luigi
Published: April 2010

Carcinosarcoma is a well‐recognized tumor even if it is an uncommon entity. Neoplasms usually occur in the oral cavity, pharynx, esophagus, larynx and skin, and have been rarely documented in the female genital tract. This case reports a patient with a diagnosis of vulvar carcinosarcoma that has been treated with radical vulvectomy and a left inguinal lymphadenectomy but she died two months later of progressive disease. Because of the extreme rarity and severe prognosis of the tumor, we believe that this is a useful addition to the literature and might serves as a reminder to physicians that a multidisciplinary approach for management should be undertaken for treatment.
Acoustic trauma evokes hyperactivity and changes in gene expression in guinea‐pig auditory brainstem
Authors: Dong Songyu , Mulders Wilhelmina H. A. M. , Rodger Jennifer , Woo Samantha , Robertson Donald
Published: April 2010

Hearing loss from acoustic trauma is a risk factor for tinnitus. Animal models using acoustic trauma have demonstrated hyperactivity in central auditory pathways, which has been suggested as a substrate for tinnitus. We used a guinea‐pig model of unilateral acoustic trauma. Within the same animals, measurements of peripheral hearing loss, spontaneous activity of single neurons in the inferior colliculus and gene expression in cochlear nucleus and inferior colliculus were combined, acutely and after recovery from acoustic trauma. Genes investigated related to inhibitory (GABA‐A receptor subunit alpha 1; glycine receptor subunit alpha 1) and excitatory neurotransmission (glutamate decarboxylase 1; glutamate receptor AMPA subunit alpha 2; glutamate receptor NMDA subunit 1), regulation of transmitter release (member of RAB family of small GTPase; RAB3 GTPase activating protein subunit 1) and neuronal excitability (potassium channel subfamily K member 15). Acoustic trauma resulted in unilateral hearing loss and hyperactivity bilaterally in inferior colliculus. Changes in expression of different mRNAs were observed in ipsilateral cochlear nucleus and in ipsi‐ and contralateral inferior colliculus, immediately after acoustic trauma, and after 2 and 4 weeks’ recovery. Gene expression was generally reduced immediately after trauma, followed by a return to near normal levels or over‐expression as recovery time increased. Different mechanisms appear to underlie the spontaneous hyperactivity observed. There is evidence of down‐regulation of genes associated with neuronal inhibition in the contralateral inferior colliculus, whereas in ipsilateral cochlear nucleus, competing actions of inhibitory and excitatory systems seem to play a major role in determining overall excitability.
Dynamic links between theta executive functions and alpha storage buffers in auditory and visual working memory
Authors: Kawasaki Masahiro , Kitajo Keiichi , Yamaguchi Yoko
Published: April 2010

Working memory (WM) tasks require not only distinct functions such as a storage buffer and central executive functions, but also coordination among these functions. Neuroimaging studies have revealed the contributions of different brain regions to different functional roles in WM tasks; however, little is known about the neural mechanism governing their coordination. Electroencephalographic (EEG) rhythms, especially theta and alpha, are known to appear over distributed brain regions during WM tasks, but the rhythms associated with task‐relevant regional coupling have not been obtained thus far. In this study, we conducted time–frequency analyses for EEG data in WM tasks that include manipulation periods and memory storage buffer periods. We used both auditory WM tasks and visual WM tasks. The results successfully demonstrated function‐specific EEG activities. The frontal theta amplitudes increased during the manipulation periods of both tasks. The alpha amplitudes increased during not only the manipulation but also the maintenance periods in the temporal area for the auditory WM and the parietal area for the visual WM. The phase synchronization analyses indicated that, under the relevant task conditions, the temporal and parietal regions show enhanced phase synchronization in the theta bands with the frontal region, whereas phase synchronization between theta and alpha is significantly enhanced only within the individual areas. Our results suggest that WM task‐relevant brain regions are coordinated by distant theta synchronization for central executive functions, by local alpha synchronization for the memory storage buffer, and by theta–alpha coupling for inter‐functional integration.
Seeking a second opinion: uncertainty in disease ecology
Authors: McClintock Brett T. , Nichols James D. , Bailey Larissa L. , MacKenzie Darryl I. , Kendall William. L. , Franklin Alan B.
Published: April 2010

Ecology Letters(2010) 13: 659–674

Analytical methods accounting for imperfect detection are often used to facilitate reliable inference in population and community ecology. We contend that similar approaches are needed in disease ecology because these complicated systems are inherently difficult to observe without error. For example, wildlife disease studies often designate individuals, populations, or spatial units to states (e.g., susceptible, infected, post‐infected), but the uncertainty associated with these state assignments remains largely ignored or unaccounted for. We demonstrate how recent developments incorporating observation error through repeated sampling extend quite naturally to hierarchical spatial models of disease effects, prevalence, and dynamics in natural systems. A highly pathogenic strain of avian influenza virus in migratory waterfowl and a pathogenic fungus recently implicated in the global loss of amphibian biodiversity are used as motivating examples. Both show that relatively simple modifications to study designs can greatly improve our understanding of complex spatio‐temporal disease dynamics by rigorously accounting for uncertainty at each level of the hierarchy.