bluuebunny/crossref_metadata_2025 huggingface dataset:
The astrocytic response towards invasive meningiomas
Authors: Zeltner L. , Schittenhelm J. , Mittelbronn M. , Roser F. , Tatagiba M. , Mawrin C. , Kim Y. J. , Bornemann A.
Published: January 2007

Invasive meningiomas disrupt the pial–glial basement membrane. This membrane is closely attached to the subpial glial endfeet forming the glia limitans. The fate of subpial astrocytes during the course of brain invasion by meningiomas is not known. In the present study we immunolabelled sections of 35 brain‐invasive meningiomas (14 meningothelial meningiomas WHO grade I, 11 atypical WHO grade II and 10 anaplastic WHO grade III) using anti‐collagen IV to label basement membrane material, and antibodies against astrocytic markers CD44, SPARC (secreted protein, acidic and rich in cysteine) and glial fibrillary acidic protein (GFAP). Astrocytes were present at the tumour–brain interface of 14/14 WHO grade I meningiomas, 9/11 WHO grade II tumours and 9/10 WHO grade III tumours. The presence of astrocytes was associated with an intact basement membrane in 11/14 WHO grade I meningiomas (P < 0.01), 6/9 WHO grade II tumours, and 6/9 WHO grade III tumours. However, tumour embedded in deep brain parenchyma lacked both an astrocytic reaction and basement membrane material. In conclusion, astrocytes eventually disappear from the tumour–brain interface during the course of meningioma infiltration. This observation might indicate that the survival of subpial astrocytes is dependent on an intact pial–glial basement membrane.
Copper deficiency elicits glial and neuronal response typical of neurodegenerative disorders
Authors: Zucconi G. G. , Cipriani S. , Scattoni R. , Balgkouranidou I. , Hawkins D. P. , Ragnarsdottir K. V.
Published: January 2007

Dysregulation of copper homeostasis has been associated with neurodegenerative diseases including Alzheimer’s disease, amyotrophic lateral sclerosis (ALS) and prion diseases. The investigation of the role of abnormal copper level in the development of neuropathological damage is essential for the understanding of pathogenetic mechanisms of these neurodegenerative disorders. Using a mouse model of perinatally induced copper deficiency, the present study analysed the response of neuronal and glial cells to copper deficiency from infancy to young adult age. In mice born and maintained after weaning on copper‐deficient diet, copper measurements indicated that at 6–8 weeks the copper levels in the brain were decreased by about 80% with respect to controls. In the brain of copper‐deficient mice, microglial and astrocytic activation was observed, mostly in the cerebral cortex and thalamus. In addition, small vacuolated globoid cells confined to the subgranular zone of the dentate gyrus were found in the third postnatal week, and larger vacuolar profiles, identified as neuronal vacuoles, were observed in layer V of the cortex after the fourth week. The spatial distribution and temporal onset of vacuolation appeared to be unrelated to those of activated microglia and astrocytes. Nitrotyrosine‐positivity was found to reflect the distribution of vacuoles in the cortex. The specific histopathological features here reported, as well as the severity of neurological deficits observed in this murine model of copper deficiency, strongly suggest that some hallmarks of neurodegenerative disorders could be mediated by multifactorial pathogenetic mechanisms that include copper dysregulation.
Caveolin‐1 and ‐2 and their relationship to cerebral amyloid angiopathy in Alzheimer's disease
Authors: Van Helmond Z. K. , Miners J. S. , Bednall E. , Chalmers K. A. , Zhang Y. , Wilcock G. K. , Love S. , Kehoe P. G.
Published: January 2007

Cerebral amyloid angiopathy (CAA) affects over 90% of patients with Alzheimer's disease (AD) and increases the risk of cerebral haemorrhage and infarction. Caveolae – cholesterol‐enriched plasmalemmal microinvaginations – are implicated in the production of amyloid β peptide (Aβ). Caveolin‐1 (CAV‐1) is essential for the formation of caveolae. Caveolin‐2 (CAV‐2) is expressed at the plasma membrane only when in a stable hetero‐oligomeric complex with CAV‐1. CAV‐1 and CAV‐2 are highly co‐expressed by endothelium and smooth muscle. Recent studies suggest that down‐regulation of CAV‐1 causes a reduction in α‐secretase activity and consequent accumulation of Aβ. We have used quantitative immunohistochemical techniques to assess the relationship between CAV‐1 and CAV‐2 with respect to Aβ accumulation in the cerebral vasculature in a series of post mortem brains. CAV‐1 and CAV‐2 were co‐expressed within the tunica media and endothelium of cerebral blood vessels. There were regional differences in CAV‐1 immunolabelling, which was significantly greater in the frontal cortex and white matter than in the parietal lobe (in both control and AD cases) or the temporal lobe (in AD alone). However, CAV‐1 labelling in AD did not differ from that in controls in any of the three lobes examined. Assessment of CAV‐1 labelling in relation to the severity of CAA showed CAV‐1 to be significantly increased in the frontal white matter in a subgroup of AD cases with absent/mild CAA compared with controls with absent/mild CAA and to AD cases with moderate/severe CAA, but the latter groups did not show significant differences from one another. CAV‐1 labelling did not vary with age, gender, APOE genotype, post mortem delay or brain weight. Only segments of blood vessels with particularly abundant Aβ and extensive loss of smooth muscle actin showed loss of CAV‐1 and CAV‐2 from the tunica media. Within these vessels endothelial CAV‐1 was preserved and discontinuous CAV‐2 labelling was noted along the outer aspect of the vessel wall. Our findings suggest that alterations in the expression of vascular CAV‐1 and CAV‐2 are unlikely to play a role in the development of CAA in AD.
De novo erythropoietin receptor (EPO‐R) expression in human neoplastic glial cells decreases with grade of malignancy but is favourably associated with patient survival
Authors: Mittelbronn M. , Capper D. , Bunz B. , Dietz K. , Goeppert B. , Ajaaj R. , Tabatabai G. , Stubenvoll F. , Schlaszus H. , Merseburger A. S. , Becker R. , Freudenstein D. , Wick W. , Weller M. , Meyermann R. , Simon P.
Published: January 2007

The erythropoietin receptor (EPO‐R) is mainly known as a regulator of erythropoiesis. However, recent studies revealed that the EPO‐R is not exclusively expressed in haematopoietic tissues but also in various cancer cell types and normal tissue such as the central nervous system (CNS). EPO‐R is up‐regulated under hypoxia and is able to counteract the deleterious effects of hypoxia on tumour growth, metastasis and treatment resistance. Therefore, the EPO–EPO‐R signalling pathway is considered as a possible target for tumour treatment. Here, we investigated brain tumour samples obtained from patients between 1993 and 2003 to study EPO‐R expression in vivo. Tissue samples included 194 gliomas of different WHO grades, additionally 25 infiltration zone samples and 31 relapses of WHO grade IV glioblastomas as well as 23 normal CNS tissue specimens to address the in vivo situation. Immunohistochemistry of the tissue microarray samples revealed significantly higher levels of EPO‐R expression in neoplastic glial cells compared with glial cells derived from normal brain. EPO‐R expression showed a highly significant decrease from low‐ to high‐grade gliomas. Age‐stratified Kaplan‐Meier analysis revealed longer survival for patients exhibiting high EPO‐R status in high‐grade gliomas. Our results show a grade‐dependent EPO‐R down‐regulation and might contribute to the understanding of high‐grade glioma resistance to radio‐ and chemotherapy as both were shown to be improved by a well functioning EPO–EPO‐R pathway in previous studies. Further studies are needed to investigate to what extent the decreased mortality in age‐stratified patient groups with high EPO‐R levels reflects a direct beneficial role of EPO‐R expression.
Immunohistochemistry for PrPSc in natural scrapie reveals patterns which are associated with the PrP genotype
Authors: Spiropoulos J. , Casalone C. , Caramelli M. , Simmons M. M.
Published: January 2007

Immunohistochemistry for PrPSc is used widely in scrapie diagnosis. In natural scrapie cases the use of immunohistochemistry (IHC) has revealed the existence of up to 12 different morphological types of immunostained deposits. The significance of this pattern variability in relation to genotype has not been studied extensively in natural disease. In this study we recorded in detail PrPSc patterns at the obex level of the medulla oblongata from 163 animals derived from 55 flocks which presented through passive surveillance in the UK and Italy. A strong association was seen between PrPSc patterns and PrP genotype, particularly in relation to codon 136. In a blind assessment of this association we were able to predict, with over 80% accuracy, the genotype of 151 scrapie cases which were presented through passive surveillance from 13 farms. The genotype of these cases was ARQ/ARQ or VRQ/VRQ. The association of PrPsc patterns with genotype was generally stronger in those farms where all the affected animals belonged to a single genotype compared with farms where both genotypes were identified, with the exception of one farm in which the genotype of all affected sheep was ARQ/ARQ and the PrPSc patterns were of the VRQ/VRQ type. Our observations support the hypothesis that the observed association between specific IHC patterns and genotypes may in fact be strain driven but in natural disease individual scrapie strains may demonstrate a genotypic tropism.
Cytokine expression in hamsters experimentally infected with Opisthorchis viverrini
Authors: JITTIMANEE J. , SERMSWAN R. W. , PUAPAIROJ A. , MALEEWONG W. , WONGRATANACHEEWIN S.
Published: January 2007

The cytokine mRNA expression of IL‐12, IFN‐γ, TGF‐β, IL‐4, and IL‐10 were investigated in spleen, liver and mesenteric lymph nodes (MLN) in hamsters experimentally infected with Opisthorchis viverrini. Animals were infected with 5, 25 or 100 metacercariae (Mc) and examined by RT‐PCR and real‐time PCR at 2 weeks, 2 and 6 months after infection. The cytokine expression was compared using HPRT. The IL‐12 was significantly expressed at 2 weeks in the liver of the 5‐ and 25‐Mc‐infected groups. It is correlated with the inflammation intensity found in the liver at the same time. The production of IFN‐γ was not increased. The significant increase in expression of IL‐10 was observed in the 6‐month group in the spleen, which may suppress the Th1 and lead to a Th2 response. The IL‐4 and TGF‐β expressions in MLN were significantly increased, and correlated with the dose of infection, especially in the 6‐month groups. The TGF‐β level in MLN was 15‐fold higher than in the uninfected control, compared to a twofold increase in spleen and liver. Because this parasite resides in the bile duct, the regulatory cytokine levels of mucosal immunity were enhanced more than those in systemic immunity. These results indicate the predominance of Th2 responses in chronic O. viverrini infection, and the high level of TGF‐β may inhibit the immune functions, which allows the parasites to evade host immune response.
Lymphotoxin alpha and tumour necrosis factor are not required for control of parasite growth, but differentially regulate cytokine production during Plasmodium chabaudi chabaudi AS infection
Authors: CLARK K. , KULK N. , AMANTE F. , HAQUE A. , ENGWERDA C.
Published: January 2007

Tumour necrosis factor (TNF) plays important roles in the pathogenesis of severe malaria, as well as in the generation of immune responses against malaria parasites. However, far less is known about the role of the closely related TNF family member lymphotoxin alpha (LTα) during malaria. We have used mice deficient in either TNF or LTα, as well as chimeric mice generated using donor bone marrow from these animals, to study the roles of these cytokines following Plasmodium chabaudi chabaudi AS infection. TNF and LTα were not required for the resolution of P. chabaudi chabaudi AS blood‐stage infection. However, LTα, but not TNF, was necessary for early IFNγ production and the regulation of IFNγ production later in infection. A similar delay to that found for IFNγ production was also observed for TNF production in LTα‐deficient mice, compared with control mice. These results identify divergent roles for TNF and LTα in the regulation of host immune responses during P. chabaudi chabaudi AS infection.
Immunization with recombinant beta‐tubulin from Trypanosoma evansi induced protection against T. evansi, T. equiperdum and T. b. brucei infection in mice
Authors: LI S.‐Q. , FUNG M.‐C. , REID S.A. , INOUE N. , LUN Z.‐R.
Published: January 2007

The beta‐tubulin gene of Trypanosoma evansi (STIB 806) was cloned and expressed in Escherichia coli. The predicted amino acid sequence of T. evansi beta‐tubulin shows 100%, 99·8%, 99·1%, and 98·6% homology with T. equiperdum, T. b. brucei, T. cruzi and T. danilewskyi, respectively, but is diverse from that of T. cyclops, showing only 51·6% of homology. Recombinant beta‐tubulin was expressed as inclusion bodies in E. coli. It was purified and renatured for immunological studies. Mice immunized with the renatured recombinant beta‐tubulin were protected from lethal challenge with T. evansi STIB 806, T. equiperdum STIB 818 and T. b. brucei STIB 940, showing 83·3%, 70% and 76·7% protection, respectively. Serum collected from the rabbit immunized with recombinant beta‐tubulin inhibited the growth of T. evansi, T. equiperdum and T. b. brucei in vitro. Serum from mice and rabbits immunized with recombinant beta‐tubulin recognized only T. evansi beta‐tubulin and not mouse beta‐tubulin. The results of this study demonstrated that the recombinant T. evansi beta‐tubulin is a potential candidate for the development of a vaccine to prevent animal trypanosomiasis caused by these three trypanosome species.
Sulphite oxidase as key enzyme for protecting plants against sulphur dioxide
Authors: LANG CHRISTINA , POPKO JENNIFER , WIRTZ MARKUS , HELL RÜDIGER , HERSCHBACH CORNELIA , KREUZWIESER JÜRGEN , RENNENBERG HEINZ , MENDEL RALF R. , HÄNSCH ROBERT
Published: January 2007

Sulphur dioxide (SO2) is known as a strongly damaging air pollutant. After conversion to sulphite in aqueous solution, it becomes a strong nucleophilic agent that attacks numerous compounds in the cell. Therefore, plants have developed a mechanism to control sulphite levels. Recently, we have cloned and characterized the enzyme sulphite oxidase (SO) from Arabidopsis thaliana. Yet, its physiological role remained unclear. Here, we describe results demonstrating that SO is essential for detoxifying excessive amounts of sulphite in the cell which is important for the survival of the plant. T‐DNA‐tagged A. thaliana plants lacking the enzyme showed a decrease in vitality during SO2 fumigation and a change in their S‐metabolites. The same was found with RNA‐interference (RNAi) plants that were generated for tobacco. On the contrary, over‐expression of SO helped the plant to survive SO2 concentrations that are detrimental for non‐transformed wild‐type (WT) plants, as was shown with poplar plants which are known to be particularly sensitive to SO2. Fumigation induced the expression of the enzyme as demonstrated by promoter–reporter gene fusion, by immunoblot analysis of SO‐protein and by induction of enzyme activity. This implies that SO, as an otherwise constitutively expressed protein, is under additional control by SO2 in the environment.
Increase in song frequency decreases spermatophore size: correlative evidence of a macroevolutionary trade‐off in katydids (Orthoptera: Tettigoniidae)
Authors: DEL CASTILLO R. C. , GWYNNE D. T.
Published: January 2007

In many katydids, the male feeds his mate with a large gelatinous spermatophore. Males of most species also produce elaborate calling songs. We predicted a negative relationship between spermatophore size and call frequency because of trade‐offs between these two costly traits. Our comparative analysis controlling phylogeny and body size supported this prediction. Although call frequency is expected to decrease with increasing body size, after controlling for phylogeny, both variables were not related. Finally, given that song frequency and spermatophore size are likely targets of sexual selection, we examined the relationship between these variables and sexual size dimorphism (SSD) which can be influenced by sexual selection on body size. We found that only female body size was positively related to SSD, suggesting that natural and/or sexual selection on female body size may be stronger than sexual selection on male and spermatophore size.
Transmission of the pine wood nematode Bursaphelenchus xylophilus through feeding activity of Monochamus galloprovincialis (Col., Cerambycidae)
Authors: Naves P. M. , Camacho S. , De Sousa E. M. , Quartau J. A.
Published: January 2007

Abstract:  Transmission of the pinewood nematode (PWN) Bursaphelenchus xylophilus (Steiner & Bührer) Nickle to Pinus pinaster Aiton branches through feeding wounds of its vector in Portugal, Monochamus galloprovincialis Olivier, was studied under laboratory conditions. All the B. xylophilus‐infected beetles transmitted nematodes to branches they fed. The transmission was more frequent during the first 6 weeks after emergence, with transmission peaks during the second and the sixth week. The adult M. galloprovincialis transmitted nematodes for a mean of 5 weeks, independently of the beetle's sex or longevity. No relation was found between beetle feeding intensity and effective transmission of B. xylophilus to the branches. The nematode transmission ceased after the ninth week, even in insects which still had B. xylophilus on their bodies. The longevity of the nematode‐free insects (control group) was slightly higher than the B. xylophilus‐infected beetles, although with no significant difference. The results emphasize the necessity to control the immature stages of M. galloprovincialis prior to emergence and develop efficient strategies to capture and eliminate the recently emerged beetles, as majority of the nematode infection of healthy pine trees occurs during a short period of few weeks after beetle emergence.
Non‐target impact of deltamethrin on soil arthropods of maize fields under conventional and no‐tillage cultivation
Authors: Badji C. A. , Guedes R. N. C. , Silva A. A. , Corrêa A. S. , Queiroz M. E. L. R. , Michereff‐Filho M.
Published: January 2007

Abstract: Deltamethrin is a commonly used insecticide for controlling its key maize pest, the fall armywormSpodoptera frugiperda(Lep., Noctuidae). Its toxicological profile is well known, but its impact on arthropods widely reported as bioindicators, mainly springtails (Collembola) and mites (Oribatida), is yet to be assessed in tropical maize fields. The treatments used to circumvent this shortcoming were conventional cultivation and no‐tillage cultivation (with a pre‐sowing application of 2,4‐D and glyphosate) systems with or without deltamethrin spraying. The deltamethrin residue analysis of soil samples by gas chromatography did not detect the insecticide 24 h after it was sprayed on the maize fields. There was no significant overall effect of deltamethrin based on principal component analysis. However, repeated‐measures analyses of variance detected significant impact of deltamethrin in a species of Nitidulidae (Coleoptera). The cultivation system also provided significant impact on Oribatida and Gamasida soil mites and on the same Nitidulidae species referred above, which were more abundant in the conventional cultivation system. Springtails were also significantly affected by the cultivation system showing greater abundance in the conventional system, except Podumorpha. Analyses using only high taxonomic levels did not allow the detection of impact in the ant assemblage assessed. The results suggest that the impact of deltamethrin on soil arthropods from tropical fields varies among species and is lower than expected. The cultivation system imposes more drastic effects on arthropod assemblage.
Consideration of the determinants of women's mental health in remote Australian mining towns
Authors: Sharma Sanjay , Rees Susan
Published: January 2007

Families in remote mining towns constitute a specific sociological group living under unique geographical and sociocultural circumstances. Isolation from friends and relatives and limited resources and opportunities for family members of mine workers are some of the distinct disadvantages of these towns. Decades ago it was observed that a large number of women in new and remote mining towns suffered from neurotic problems. In contemporary times there is a deficit of knowledge about the mental health of women in remote mining towns. However, there are certain indicators of significant mental distress among women living in these particular environments. Deriving from a review of literature, this paper explores various mining work‐related issues and sociocultural settings and processes within remote mining towns that could possibly exert coercive pressures on the psychological health of female partners of mine workers and their relationship well‐being. The paper suggests that work schedules and preponderance of men in mining jobs help promote a patriarchal culture within the community and the family; thereby marginalising women to a secondary status. Limited opportunities and resources within the community isolate women to domestic lives; while atypical work rosters associated with mining employment could negatively impact on the relationship well‐being of couples. The paper recommends that an inquiry into psychiatric well‐being among women of remote mining communities needs to consider the sociocultural structure and processes within these communities, and the structural nature of the mining job that could be responsible for role strain‐induced stress and mental health problems among these women.
Medical students and rural general practitioners: Congruent views on the reality of recruitment into rural medicine
Authors: Eley Diann , Young Louise , Shrapnel Marilyn , Wilkinson David , Baker Peter , Hegney Desley
Published: January 2007

Objective:  In‐depth exploration of the perceptions, experiences and expectations of current long‐term rural GPs and medical students intent on a rural career, regarding the current and future state of rural medicine.

Design:  Qualitative study using semistructured interviews.

Setting:  Rural and remote towns in Central and Southern Queensland and the School of Medicine, University of Queensland.

Participants:  Thirteen rural GPs with 10–40 years experience. Medical students (five second‐ and seven third‐year), all of whom are members of a rural students' club and have an intention to pursue rural practice. Interviews were conducted between August and December 2004.

Main outcome measures:  Emergent themes relating to participant perceptions of the current and future state of rural medicine.

Results:  Despite large differences in generation and experience, medical students and rural GPs hold similar perceptions and expectations regarding the current and future state of rural practice. In particular, they cite a lack of professional support at the systems level. This includes specific support for: continuing medical education to obtain and retain the skills necessary for rural practice; dealing with the higher risks associated with procedural work; and consequences of medico‐legal issues and workforce shortage issues such as long hours and availability of locums.

Conclusions:  Issues relating to recruitment and retention of the rural health workforce are identified by both cohorts as relating to professional support. Medical schools and institutional support systems need to join forces and work together to make rural practice a viable career in medicine.
‘Shared Care – Shared Dream’: Model of shared care in rural Australia between mental health services and general practitioners
Authors: Samy D. Chinna , Hall Philip , Rounsevell Jacquie , Carr Rodney
Published: January 2007

Objective:  To identify a working model between rural and remote mental health services and the local GPs in Australia.

Design:  Postal questionnaire to assess the GPs' satisfaction level with the involvement of the mental health services in their ongoing management of mentally ill in the community.

Result:  There was a greater sense of satisfaction with the mental health services over the five years this program was implemented.

Conclusion:  This study offers a model on how a rural mental health service could enter into a shared care program with the local GP practice and achieve a greater level of satisfaction in serving the rural communities in Australia.
Satisfaction with caring and living conditions in nursing homes: Views of elderly persons, next of kin and staff members
Authors: Berglund Anna‐Lena
Published: January 2007

The aim was to describe satisfaction with the caring and living conditions of elderly persons in nursing homes, expressed by the elderly persons, next of kin and staff members. Elderly persons were interviewed about their caring and living conditions. Next of kin and staff members completed a questionnaire about satisfaction with caring and living conditions of elderly persons. The main results showed significantly low levels of satisfaction regarding: altered health, influence on care, rehabilitation and meaningful occupation, as expressed by the elderly persons. Next of kin stated low satisfaction with staff contacts, influence on care, rehabilitation from staff and meaningful occupation for their elderly relatives. Staff members expressed low satisfaction with influence on care and meaningful occupation. The results present important evidence to guide the heads of nursing homes and those responsible for elderly care, which will help to improve the caring and living conditions of elderly persons.
Sense or no‐sense: The nurse as embodied ethnographer
Authors: Edvardsson David , Street Annette
Published: January 2007

Researching in familiar environments brings about challenges as nurses are learned to tune out their senses to give expert nursing care, and contemporary nursing research using observations has been criticized for being disembodied—not often using senses other than sight. This article draws on experiences from a fieldwork study of palliative and aged care environments to show how a deliberate use of the senses can enhance the richness of nursing research and open up new avenues for investigation. Examples from a reflexive fieldwork journal are presented to demonstrate how sensate experiences was used in a reflexive process that led into areas that otherwise might have remained unexplored. §The authors argue that the interplay between sensate experiences and analytical logic can bring the background to the foreground and provide new ways of making the familiar unfamiliar. In making sense of what residing in health care environments might mean, an embodied research activity is fruitful.
Hearing what older consumers say about participation in their care
Authors: Penney Wendy , Wellard Sally J
Published: January 2007

A study exploring older people's participation in their care in acute hospital settings reveals both consumers' and nurses' views of participation. Using a critical ethnographic design, data were collected through participant observation and interviews from consumers in acute care settings who were over 70 years old and nurses who were caring from them. Thematic analysis identified that older people equated participation with being independent. Importantly, consumers highlighted the complexity of the notion of participation when describing situations where they were unable to participate in their own care. The difficulties in communicating with health professionals and an inability to administer their own medications in inpatient settings were identified as barriers to participation. Understanding what consumers believe participation means provides a starting point for developing meaningful partnerships between health professionals and people receiving care.
Reduced shear stress and disturbed flow may lead to coronary aneurysm and thrombus formations
Authors: OHKUBO TAKASHI , FUKAZAWA RYUJI , IKEGAMI EI , OGAWA SHUNICHI
Published: January 2007

Background: With Kawasaki disease it is important to clarify the mechanisms of coronary artery aneurysm and thrombus to avoid acute myocardial infarction. The authors tested the hypothesis that shear stress is reduced at coronary branching sites and in coronary artery aneurysms, and that this reduction of shear stress can promote formation of coronary artery aneurysms and thrombus.

Methods: The subjects were 111 children with Kawasaki disease with left coronary artery aneurysms, classified into three groups: giant coronary artery aneurysm (n= 28, diameter of coronary artery >8 mm), aneurysm (n= 44, diameter of coronary artery =8 mm), and normal‐appearing coronary (n= 39). Averaged peak flow velocity (APV), flow patterns and shear stress were measured and calculated at normal‐appearing coronary vessels, left coronary artery branching sites and intra‐coronary aneurysm using flow wire, and coronary angiography. Also, presence and appearance of thrombus were detected by intravascular ultrasonography.

Results: The authors found that 90.3% of the coronary artery aneurysms occurred at major left coronary branching sites. APV and shear stress were significantly decreased in giant coronary artery aneurysms (APV, 7.1 ± 2.1 cm/s; shear stress, 3.8 ± 2.1 dyne/cm2) and at the left coronary artery branching site (APV, 9.1 ± 1.2; shear stress, 1±±.2 3.0). In total, 20 of 24 thrombi were detected only in giant aneurysm, and all patients exhibited disturbed flow pattern in their giant coronary artery aneurysms.

Conclusions: Reduced shear stress and disturbed flow pattern may lead to coronary artery aneurysm and thrombus formation.
Hypernatremic dehydration in the newborn period and long‐term follow up
Authors: ERGENEKON EBRU , UNAL SUNA , GÜCÜYENER KIVILCIM , SOYSAL S¸EBNEM , KOÇ ESI˙N , OKUMUS¸ NURULLAH , TÜRKYILMAZ CANAN , ONAL ESRA , ATALAY YILDIZ
Published: January 2007

Background: Hypernatremic dehydration due to inadequate fluid intake can be a significant problem during the neonatal period and thereafter. The objective of the present study was to evaluate the term newborn infants admitted to Gazi University Hospital neonatal intensive care unit (NICU) for hypernatremic dehydration between June 2001 and June 2003 and compare the results with those of the literature search performed via MEDLINE for infants with the same diagnosis.

Methods: Infants with weight loss ≥10% were evaluated for hypernatremia and the ones with serum Na level ≥150 mEq/L were admitted to NICU. Long‐term follow‐up evaluations were performed using Bayley Scales of Infant Development I (BSID I) and Bayley Infant Neurodevelopmental Screener (BINS) tests.

Results: Between June 2001 and June 2003, 28 newborns were admitted to NICU with hypernatremic dehydration. Literature review found 178 newborns with the same diagnosis since 1979 and detailed information was available for 150 patients. In the study and MEDLINE groups, respectively mean days of admission were 3.39 and 11.7; mean serum sodium, 156.5 and 178.6 mEq/L; and mean % weight loss, 11.5 and 25.7. Long‐term follow up was performed in 15 patients from the study group, and two patients were found to be severely neurologically delayed. Five patients were found to have moderate risk scores by BINS tests.

Conclusions: Early follow‐up visits of newborns soon after discharge are important to determine risk for hypernatremic dehydration. Long‐term follow up of this group of babies is also required to gather knowledge about the repercussions of early hypernatremic dehydration later in life.
Detection of anaerobic toluene and hydrocarbon degraders in contaminated aquifers using benzylsuccinate synthase (bssA) genes as a functional marker
Authors: Winderl Christian , Schaefer Sabine , Lueders Tillmann
Published: January 2007

Benzylsuccinate synthase (Bss) is the key enzyme of anaerobic toluene degradation and has been found in all anaerobic toluene degrading bacterial isolates tested. However, only a few pure cultures capable of anaerobic toluene oxidation are available to date, and it is important to understand the relevance of these model organisms for in situ bioremediation of hydrocarbon‐contaminated aquifers. Due to their phylogenetic dispersal, it is not possible to specifically target anaerobic toluene degraders using marker rRNA genes. We therefore established an assay targeting a ∼794 bp fragment within the Bss alpha‐subunit (bssA) gene, which allows for the specific detection and affiliation of both known and unknown anaerobic degraders. Three distinct tar‐oil‐contaminated aquifer sites were screened for intrinsic bssA gene pools in order to identify and compare the diversity of hydrocarbon degraders present at these selected sites. We were able to show that local diversity patterns of degraders were entirely distinct, apparently highly specialized and well‐adapted to local biogeochemical settings. Discovered at one of the sites were bssA genes closely related to that of Geobacter spp., which provides evidence for an importance of iron reduction for toluene degradation in these sediments. Retrieved from the other two sites, dominated by sulfate reduction, were previously unidentified bssA genes and also deeply branching putative bssA homologues. We provide evidence for a previously unrecognized diversity of anaerobic toluene degraders and also of other hydrocarbon degraders using fumarate‐adding key reactions in contaminated aquifers. These findings enhance our current understanding of intrinsic hydrocarbon‐degrading microbial communities in perturbed aquifers and may have potential for the future assessment and prediction of natural attenuation based on degradation genes.
Molecular and morphological characterization of the association between bacterial endosymbionts and the marine nematode Astomonema sp. from the Bahamas
Authors: Musat Niculina , Giere Olav , Gieseke Armin , Thiermann Frank , Amann Rudolf , Dubilier Nicole
Published: January 2007

Marine nematode worms without a mouth or functional gut are found worldwide in intertidal sandflats, deep‐sea muds and methane‐rich pock marks, and morphological studies show that they are associated with endosymbiotic bacteria. While it has been hypothesized that the symbionts are chemoautotrophic sulfur oxidizers, to date nothing is known about the phylogeny or function of endosymbionts from marine nematodes. In this study, we characterized the association between bacterial endosymbionts and the marine nematode Astomonema sp. from coral reef sediments in the Bahamas. Phylogenetic analysis of the host based on its 18S rRNA gene showed that Astomonema sp. is most closely related to non‐symbiotic nematodes of the families Linhomoeidae and Axonolaimidae and is not closely related to marine stilbonematinid nematodes with ectosymbiotic sulfur‐oxidizing bacteria. In contrast, phylogenetic analyses of the symbionts of Astomonema sp. using comparative 16S rRNA gene sequence analysis revealed that these are closely related to the stilbonematinid ectosymbionts (95–96% sequence similarity) as well as to the sulfur‐oxidizing endosymbionts from gutless marine oligochaetes. The closest free‐living relatives of these gammaproteobacterial symbionts are sulfur‐oxidizing bacteria from the family Chromatiaceae. Transmission electron microscopy and fluorescence in situ hybridization showed that the bacterial symbionts completely fill the gut lumen of Astomonema sp., suggesting that these are their main source of nutrition. The close phylogenetic relationship of the Astomonema sp. symbionts to known sulfur‐oxidizing bacteria as well as the presence of the aprA gene, typically found in sulfur‐oxidizing bacteria, indicates that the Astomonema sp. symbionts use reduced sulfur compounds as an energy source to provide their hosts with nutrition.
Urethral replacement using epidermal cell‐seeded tubular acellular bladder collagen matrix
Authors: Fu Qiang , Deng Chen‐liang , Liu Wei , Cao Yi‐lin
Published: January 2007

OBJECTIVES

To investigate the feasibility of replacing urinary epithelium cells with foreskin epidermal cells to reconstruct engineered anterior urethra with an acellular collagen matrix.

MATERIALS AND METHODS

Acellular collagen matrices were generated from allogeneic rabbit bladder submucosa. In nine rabbits, autologous foreskin epidermal cells were isolated, expanded in vitro, and labelled with 5‐bromo2’‐deoxy‐uridine (BrdU) before seeding onto a tubular acellular collagen matrix (1.5 × 1 cm). In male rabbits, a urethral mucosal defect was created, and urethroplasty performed with a tubular acellular collagen matrix seeded with epidermal cells (nine rabbits) or with a matrix with no cell seeding (nine rabbits; control group). Urethrography was done at 1, 2 and 6 months after grafting. The urethral grafts were harvested and analysed grossly and histologically.

RESULTS

In the control group, gross views and urethrography revealed stricture of repaired defects at the different sample times. In the experimental group, a wide urethral calibre was maintained with no sign of strictures. Histology in the control group showed a single layer of epithelium cells with disorganized muscle fibre bundles in the submucosa layer at 1 month after grafting, and a transitional cell layer surrounded by disorganized muscle fibre bundles at 2 and at 6 months. Grafts seeded with epidermal cells formed a single‐layer structure by 1 month, and at 2 and 6 months there were several layers of epidermal cells with abundant vessels in the submucosa. There was an evident margin between graft epidermal cells and host epithelium at 6 months. The implanted cells expressed keratin, shown by staining with anti‐pancytokeratins. Immunofluorescence for BrdU confirmed the presence of implanted epidermal cells at 1 month after grafting; there were fewer positive cells at the implantation site at 2 months. At 6 months, there were several layers of epidermal cells with no signs of BrdU staining.

CONCLUSIONS

Urethral reconstruction was better with an acellular collagen matrix seeded with epidermal cells than with the acellular collagen matrix alone. Foreskin epidermal cells seem adequate in replacing urethral epithelium cells for urethral reconstruction.
Functional heterogeneity of prostatic intraepithelial neoplasia: the duration of hormonal therapy influences the response
Authors: Kang Tyler Y. , Nichols Peter , Skinner Eila , Groshen Susan , Valin Greg , Ye Wei , Raghavan Derek
Published: January 2007

OBJECTIVES

To use a clinical model of androgen‐deprivation therapy (ADT) followed by radical prostatectomy (RP) to test the hypothesis that prostatic intraepithelial neoplasia (PIN, a premalignant lesion of the prostate causally linked to prostate cancer) is heterogeneous for hormone responsiveness, which might explain aspects of the heterogeneity of the natural history of prostate cancer, for although ADT has been used to reduce prostate cancer, there are controversial data on the effect of ADT on PIN.

PATIENTS AND METHODS

We assessed retrospectively patients with biopsy‐confirmed prostate cancer who had RP; some patients had received ≥3 months of ADT at the discretion of their surgeons, and patients from the same cohort who did not have ADT were used as controls. Patients were sequentially selected from the database and their pathology slides were reviewed by a pathologist unaware of the initial presence of PIN (assessed by an independent observer). Fisher’s exact test was used to compare the proportions of patients who had residual PIN in the study and control groups. Exact logistic regression was used to evaluate the duration of ADT on PIN regression.

RESULTS

Eighteen patients initially diagnosed with PIN who had no ADT were identified, and 28 with PIN who had ADT were also assessed. All patients who had had no ADT had residual PIN, whereas seven of 28 receiving ADT had no residual PIN (P = 0.043). The evaluation of ADT between responders and nonresponders showed a statistically significant association between PIN regression and the duration of ADT (P <0.001). However, the response of PIN to ADT was not uniform, as 16% of patients on ADT for >6 months had residual PIN, suggesting variable sensitivity of PIN to ADT.

CONCLUSION

These results show that ADT causes PIN to regress, and that there is heterogeneity in this effect with the duration of ADT. We propose future prospective, multicentre, randomized trials in which the effect of ADT on PIN is characterized further.
Acquisition Premiums, Subsequent Workforce Reductions and Post‐Acquisition Performance
Authors: Krishnan Hema A. , Hitt Michael A. , Park Daewoo
Published: January 2007

abstract This study suggests that paying acquisition premiums leads to workforce reductions in the merged firm, which in turn results in poorer post‐acquisition performance. This issue is important to scholars and practising managers given the pervasiveness and importance of knowledge and human capital to competitive advantage. In a sample of 174 major related acquisitions completed in the period 1992–98, results show a positive relationship between the premium paid for an acquisition and subsequent workforce reductions, controlling for a number of alternative explanations. Additionally, workforce reduction mediates the negative relationship between premiums and post‐acquisition performance. The results suggest that the effects of workforce reductions following large premiums paid for the acquired firm can be detrimental to the interests of the organization.
Identifying, Enabling and Managing Dynamic Capabilities in the Public Sector*
Authors: Pablo Amy L. , Reay Trish , Dewald James R. , Casebeer Ann L.
Published: January 2007

abstract  In this paper, we examine how a public sector organization developed a new strategic approach based on the identification and use of an internal dynamic capability (learning through experimenting). In response to the need for continual performance improvement in spite of reduced financial resources, this organization engaged in three overlapping phases as they shifted to this strategic approach. First, managers identified appropriate latent dynamic capabilities. Next, they used their leadership skills and built on established levels of trust to enable the use of these dynamic capabilities. Finally, they managed the tension between unrestricted development of local initiatives and organizational needs for guidance and control.
Contrasting Institutional and Performance Accounts of Environmental Management Systems: Three Case Studies in the UK Water & Sewerage Industry*
Authors: Schaefer Anja
Published: January 2007

abstract This paper presents results from a longitudinal, qualitative study into the adoption of environmental management systems (EMS) in three companies in the UK water & sewerage industry. Based on institutional theory and the literature on EMS, four factors related to the adoption of EMS are identified: external and internal institutional forces, environmental performance issues, and economic performance issues. While previous literature has often assumed a balance of performance and institutional factors or a preponderance of performance factors, the results of this study indicate that institutional forces are the predominant drivers. The results further indicate that environmental performance issues become less important over time, whereas institutional drivers and economic performance rationales increase in importance over time. While conforming to institutional pressures can result in improved economic performance of a company, adoption of environmental management systems mostly on the basis of institutional and economic factors has wider repercussions for the state of corporate environmental management and progress towards greater ecological sustainability of business.
Market Integration and Economic Development: A Long‐run Comparison
Authors: Keller Wolfgang , Shiue Carol H.
Published: January 2007

How much of China’s recent economic performance can be attributed to market‐oriented reforms introduced in the last two decades? A long‐run perspective may be important for understanding the process of economic development occurring today. This paper compares the integration of rice markets in China today and 270 years ago. In the eighteenth century, transport technology was non‐mechanized, but markets were close to being free. We distinguish local harvest and weather from aggregate sources of price variation in a historical sample and in a similarly constructed contemporary sample. Findings indicate the degree of market integration in the 1720s is a very good predictor of per capita income in the 1990s. Moreover, the current pattern of interregional income in China is strongly linked to persistent geographic factors that were already apparent several centuries ago, well before the enactment of modern reform programs.
Endogenous Growth, Taxes and Government Spending: Theory and Evidence*
Authors: Denaux Zulal S.
Published: January 2007

This paper provides a theoretical and empirical investigation of the simultaneous effects of taxes and government spending on long‐run economic growth in an endogenous growth framework. A two‐sector model is considered: one sector produces physical output and the other produces human capital. Government expenditure is divided into several categories, and several types of taxes are included. The property tax is especially interesting because it is a major source of revenue for local government. The theoretical model is estimated using annual panel data from North Carolina counties. This study finds that state‐level fiscal policies affect economic growth but county‐level fiscal policies do not.
R&D Policies and Endogenous Growth: A Dynamic General Equilibrium Analysis of the Case for Canada*
Authors: Ghosh Madanmohan
Published: January 2007

This paper utilizes a general equilibrium R&D model of endogenous growth via increasing capital variety to examine the impact of alternative policies on productivity and economic growth. The model is calibrated using data from the Canadian economy. Findings reveal that direct incentives such as subsidies to R&D activities would have the highest productivity impact on the Canadian economy, that an increase in subsidies to the users of R&D capital (output) would have a positive but smaller impact, and trade liberalization would have minimal effects on productivity growth via its impact on international R&D spillovers.
Perfect Simulation for Length‐interacting Polygonal Markov Fields in the Plane
Authors: VAN LIESHOUT M. N. M. , SCHREIBER T.
Published: January 2007

Abstract.  The purpose of this paper was to construct perfect samplers for length‐interacting Arak–Clifford–Surgailis polygonal Markov fields in the plane with nodes of order 2 (V‐shaped nodes). This is achieved by providing for the polygonal fields a hard core marked point process representation with individual points carrying polygonal loops as their marks, so that the coupling from the past and clan of ancestors routines can be adopted.
Fiscal Transfers and Distributive Conflict in a Simple Endogenous Growth Model with Unemployment
Authors: Bonatti Luigi
Published: January 2007

In the simplified formal treatment proposed in this paper, a decrease in a policy parameter - the ratio of total tax revenues to GDP - can monotonically increase long-term growth rate and may lead to a higher employment level. This notwithstanding, the paper shows that the redistributive implications of such a decrease may induce the wage earners to oppose it. As a consequence, policy-makers reflecting social preferences may undertake redistributive transfers generating persistent unemployment and lowering growth even if commitment technologies allowing them to follow preannounced tax policies were feasible.