bluuebunny/crossref_metadata_2025 huggingface dataset:
Spreading introgression in the wake of a moving contact zone
Authors: SECONDI JEAN , FAIVRE BRUNO , BENSCH STAFFAN
Published: April 2006

An increasing number of studies describe moving hybrid zones. This raises the issue of their actual frequency and emphasizes the need for methods that enable the detection of zone movements without historical records. Asymmetric introgression, usually considered as a signature of geographical shift, might be misleading when applied to mitochondrial or potentially non‐neutral markers. We investigated mitochondrial and genomic introgression, using 30 AFLP derived markers, in a well‐documented moving avian contact zone between two warblers. We found no instances of cross‐species transmission of mitochondrial DNA but we detected nuclear introgression. Introgression levels were higher in the expanding species. Highest introgression was observed in populations that recently became allopatric than in current sympatric populations, which suggests that alien genetic material mainly spread at the time just before the receding species became extinct. We propose that either local recruitment or positive selection on some loci contribute to this pattern. Furthermore, we propose that, when the rarefaction of sexual partners drive the hybridization process, movement could be revealed by introgression peaking on the rear edge of the moving zone, or in its close vicinity.
Reduction of Botrytis cinerea sporulation in sweet basil by altering the concentrations of nitrogen and calcium in the irrigation solution
Authors: Yermiyahu U. , Shamai I. , Peleg R. , Dudai N. , Shtienberg D.
Published: April 2006

Current measures for suppressing grey mould (Botrytis cinerea) on sweet basil rely on fungicide applications and climate control. In this study, the nitrogen and calcium concentrations in the standard irrigation solution (7·2 and 1·3 mm, respectively) were varied in a series of experiments conducted in pots and large containers. Treatments differed in the N or Ca concentrations supplied, and effects on host response were determined in detached stem segments, individual plants and plots. Effects of the two elements on grey mould incidence, lesion size and rate of disease progression were erratic and rarely significant, but decreasing the concentration of N and increasing the concentration of Ca in the irrigation solution decreased sporulation of B. cinerea. In some cases, however, altering the standard irrigation solution resulted in significantly lower yields. Analyses of mineral contents in the shoots suggested that yields were not impaired when N content in the shoots was not reduced below 2·9% and Ca content was not raised above 1·3%. These findings were used to compose a modified irrigation solution containing half of the N (3·6 mm) and double of the Ca (2·55 mm) concentrations in the standard irrigation solution. The modified irrigation solution significantly reduced sporulation of B. cinerea without affecting crop yield.
Expression of Idiotypic Antibodies‐1 and ‐2 and Breastfeeding in Relation to Antibody Levels Against Haemophilus Influenzae Type b in Children
Authors: Silfverdal S. A. , Bodin L. , Ulanova M. , Hahn‐Zoric M. , Hanson L. Å. , Olcén P.
Published: April 2006

The aim of the study was to determine the concentrations of serum antibodies against Haemophilus influenzae type b in preschool children in relation to the distribution of idiotypic antibodies 1 and 2 (Id‐1 and Id‐2) and the exposure to breastfeeding in infancy. Sera were obtained from 74 control children recruited in an earlier case‐control study before the introduction of general Hib vaccination. Duration of breastfeeding was monitored, and prevalence of noninvasive infections was registered. Concentrations of IgG1 and IgG2 anti‐Hib, as well as of total Id‐1 and Id‐2, were determined in ELISA. The expression of Id‐1 antibodies increased with age in contrast to the Id‐2 antibodies that were found only in children up to 24 months of age. Expression of Id‐1 antibodies was positively correlated with higher anti‐Hib levels of both the IgG1 and IgG2 isotype. Children expressing Id‐2 antibodies showed higher IgG2 anti‐Hib concentrations than those who did not have Id‐2 (P = 0.001). The concentrations of neither Id‐1 nor Id‐2 antibodies were related to the duration of breastfeeding. Duration of breastfeeding was related to increased anti‐Hib IgG2 in healthy children above 18 months of age. These study shows that the expression of idiotype‐1 and idiotype‐2 antibodies was associated with higher IgG2 anti‐Hib concentration and that breastfeeding could enhance the anti‐Hib IgG2 production in children.
Interleukin‐6 Trans‐Signalling in Chronic Inflammation and Cancer
Authors: Scheller J. , Ohnesorge N. , Rose‐John S.
Published: April 2006

Interleukin‐6 (IL‐6) is a cytokine, which plays an important role in many chronic inflammatory diseases. IL‐6 belongs to a family of 10 cytokines, which all act via receptor complexes containing the cytokine receptor subunit gp130. On cells, IL‐6 first binds to a specific membrane‐bound IL‐6R and the complex of IL‐6 and IL‐6R interacts with gp130 leading to signal initiation. Whereas gp130 is widely expressed throughout the body, the IL‐6R is only found on some cells including hepatocytes and some leucocytes. A soluble form of the IL‐6R is an agonist capable of transmitting signals through interaction with the gp130 protein. In vivo, the IL‐6/soluble IL‐6R complex stimulates several types of target cells, which are unresponsive to IL‐6 alone, as they do not express the membrane‐bound IL‐6R. We have named this process trans‐signalling. We provided evidence that a soluble form of the IL‐6 family signalling receptor subunit gp130 is the natural inhibitor of IL‐6 trans‐signalling responses. We showed that in chronic inflammatory diseases such as inflammatory bowel disease, peritonitis, rheumatoid arthritis, asthma as well as in colon cancer, IL‐6 trans‐signalling is critically involved in the maintenance of the disease state. Moreover, in all these animal models, the progression of the disease can be interrupted by specifically interfering with IL‐6 trans‐signalling using recombinant‐soluble gp130Fc protein. The pathophysiologic mechanisms by which the IL‐6/soluble IL‐6R complex perpetuates the inflammatory state are discussed.
Comparative efficacy of chloroquine and sulphadoxine – pyrimethamine in pregnant women and children: a meta‐analysis
Authors: Kalanda Gertrude C. , Hill Jenny , Verhoeff Francine H. , Brabin Bernard J.
Published: April 2006

Objective  To compare the efficacy of chloroquine and sulphadoxine–pyremethamine against Plasmodium falciparum infection in pregnant women and in children from the same endemic areas of Africa, with the aim of determining the level of correspondence in efficacy determinations in these two risk groups.

Methods  Meta‐analysis of nine published and unpublished in vivo antimalarial efficacy studies in pregnant women and in children across five African countries.

Results  Pregnant women (all gravidae) were more likely to be sensitive than children to both chloroquine (odds ratio: 2.07; 95% confidence interval: 1.5, 2.9) and sulphadoxine–pyrimethamine (odds ratio: 2.66; 95% confidence interval: 11.1, 6.7). Pregnant women demonstrated an almost uniform increased sensitivity for peripheral parasite clearance at day 14 compared with children. This finding was consistent across a wide range of drug sensitivities. Primigravidae at day 14 showed lower clearance to antimalarial drugs than multigravidae (P < 0.05). There was no significant difference between parasite clearance in primigravidae and in children.

Conclusion  The greater drug sensitivity in pregnant women probably indicates differences in host susceptibility rather than parasite resistance. Parasite sensitivity patterns in children may be a suitable guide to antimalarial policy in pregnant women.
Circumsporozoite protein gene diversity among temperate and tropical Plasmodium vivax isolates from Iran
Authors: Zakeri Sedigheh , Abouie Mehrizi Akram , Djadid Navid Diparast , Snounou Georges
Published: April 2006

To date, there is no information on the genetic diversity of the circumsporozoite protein (CSP), a leading vaccine candidate, in Plasmodium vivax populations circulating in Iran. The gene for this protein, Pvcsp, was amplified from 374 P. vivax isolates collected in the temperate northern, and in the tropical southern endemic areas. PCR–RFLP analysis of the repeated central region revealed that the parasites collected in the northern area were almost exclusively of the VK210 type. Parasites collected in the south‐eastern areas were of both VK210 and VK247 types. We detected VK210 parasite in 70.5% of the samples, VK247 parasites in 17.5% and mixed type infections in 12% of the isolates. Sequence analysis of 137 isolates obtained from both areas identified a total of 25 distinct genotypes. The degree of genetic diversity was generally higher for the tropical (21 genotypes) than the temperate (7 genotypes) P. vivax populations, a difference possibly reflecting the high cross‐border exchanges between Afghanistan and Pakistan and southern Iran. Interestingly, all but two VK210 type isolates sequenced harboured a 36‐bp post‐repeat insert previously only observed in North Korea and China. This large‐scale survey of parasite diversity in the Eastern Mediterranean Region provides a set of baseline data suitable for future molecular epidemiological studies of P. vivax.
Accuracy of resource selection functions across spatial scales
Authors: Meyer Carolyn B. , Thuiller Wilfried
Published: April 2006

Resource selection functions (RSFs) can be used to map suitable habitat of a species based on predicted probability of use. The spatial scale may affect accuracy of such predictions. To provide guidance as to which spatial extent or grain is appropriate and most accurate for animals, we used the concept of hierarchical selection orders to dictate extent and grain. We conducted a meta‐analysis from 123 RSF studies of 886 species to identify differences in prediction success that might be expected for five selection orders. Many studies do not constrain spatial extent to the grain of the next broader selection order in the hierarchy, mixing scaling effects. Thus, we also compared accuracy of single‐ vs. multiple‐grain RSFs developed at the unconstrained extent of an entire study area. Results suggested that the geographical range of a species was the easiest to predict of the selection orders. At smaller scales within the geographical range, use of a site was easier to predict when environmental variables were measured at a grain equivalent to the home‐range size or a microhabitat feature required for reproduction or resting. Selection of patches within home ranges and locations of populations was often more difficult to predict. Multiple‐grain RSFs were more predictive than single‐grain RSFs when the entire study area was considered available. Models with variables measured at both small and large (> 100 ha) grains were usually most predictive, even for many species with small home ranges. Multiple‐grain models may be particularly important for species with moderate dispersal abilities in habitat fragments surrounded by an unsuitable matrix. We recommend studies should no longer address only one grain to map animal species distributions.
Pre‐operative measurement of heart rate variability predicts hypotension during general anesthesia
Authors: Huang C.‐J. , Kuok C.‐H. , Kuo T. B. J. , Hsu Y.‐W. , Tsai P.‐S.
Published: April 2006

Background:  Peri‐operative hymodynamic instability is one of the major concerns for anesthesiologists when performing general anesthesia for individuals with autonomic dysfunction. The purpose of this study was to examine the potential usage of pre‐operative measurement of heart rate variability (HRV) in identifying which individuals, with or without diabetes, may be at risk of blood pressure (BP) instability during general anesthesia.

Methods:  We studied 46 patients with diabetes and 87 patients without diabetes ASA class II or III undergoing elective surgery. Participants' cardiovascular autonomic function and HRV were assessed pre‐operatively, and hymodynamic parameters were monitored continuously intra‐operatively by an independent observer.

Results:  Only 6% of the participants were classified as having cardiovascular autonomic neuropathy (CAN) based on traditional autonomic function tests whereas 15% experienced hypotension. Total power (TP, P = 0.006), low frequency (LF, P = 0.012) and high frequency (HF, P = 0.028) were significantly lower in individuals who experienced hypotension compared with those who did not. Multivariate logistic regression analysis revealed that TP [odds ratio (OR) = 0.15, 95% confidence interval (CI) = 0.05–0.47, P = 0.001] independently predicted the incidence of hypotension, indicating that each log ms2 increase in total HRV lowers the incidence of hypotension during general anesthesia by 0.15 times. After stepwise multiple linear regression analysis (R2 = 11.5%), HF (β = −11.1, SE = 2.79, P < 0.001) was the only independent determinant of the magnitude of systolic blood pressure (SBP) reduction at the 15th min after tracheal intubation.

Conclusions:  Spectral analysis of HRV is a sensitive method for detecting individuals who may be at risk of BP instability during general anesthesia but may not have apparent CAN according to traditional tests of autonomic function.
Evaluation of a new recommendation for improved cuffed tracheal tube size selection in infants and small children
Authors: Salgo B. , Schmitz A. , Henze G. , Stutz K. , Dullenkopf A. , Neff S. , Gerber A. C. , Weiss M.
Published: April 2006

Background:  The purpose of this study was to evaluate a new recommendation for tracheal tube size selection using second‐generation Microcuff paediatric endotracheal tubes (PETs) with optimized outer diameter (OD) of the distal tube.

Methods:  With Ethics Committee approval, patients aged from birth to 5 years, requiring general anaesthesia with orotracheal intubation, were included. Tracheal tube sizes were selected as follows: internal diameter (ID) 3.0 mm, birth (if ≥3 kg) to <6 months; ID 3.5 mm, 6 to <18 months; ID 4.0 mm, 18 months to <3 years; ID 4.5 mm, 3 to <5 years. Tracheal tubes with the cuff not inflated were classified as too large if no air leak was obtained at an airway pressure of ≤20 cmH2O. Post‐intubation stridor requiring therapy was noted.

Results:  Three hundred and fifty children were studied. Nine tracheal tubes (2.6%) were too large and had to be exchanged: in patients requiring tracheal tubes of ID 3.0 mm and 3.5 mm, three and four tracheal tubes, respectively, and, in patients requiring tracheal tubes of ID 4.0 mm and 4.5 mm, one tracheal tube in each group. In three patients (0.9%), post‐intubation stridor occurred which required therapy.

Conclusion:  The new recommendation presented for the use of second‐generation Microcuff PETs with improved OD to ID ratio allows the selection of cuffed tracheal tubes with larger IDs than previously recommended for small children without increased need for tracheal tube exchange or increased incidence of post‐intubation stridor in these age groups.
The effect of phenotypic plasticity on evolution in multipeaked fitness landscapes
Authors: Borenstein E. , Meilijson I. , Ruppin E.
Published: April 2006

When facing the challenge of developing an individual that best fits its environment, nature demonstrates an interesting combination of two fundamentally different adaptive mechanisms: genetic evolution and phenotypic plasticity. Following numerous computational models, it has become the accepted wisdom that lifetime acclimation (e.g. via learning) smooths the fitness landscape and consequently accelerates evolution. However, analytical studies, focusing on the effect of phenotypic plasticity on evolution in simple unimodal landscapes, have often found that learning hinders the evolutionary process rather than accelerating it. Here, we provide a general framework for studying the effect of plasticity on evolution in multipeaked landscapes and introduce a rigorous mathematical analysis of these dynamics. We show that the convergence rate of the evolutionary process in a given arbitrary one-dimensional fitness landscape is dominated by the largest descent (drawdown) in the landscape and provide numerical evidence to support an analogous dominance also in multidimensional landscapes. We consider several schemes of phenotypic plasticity and examine their effect on the landscape drawdown, identifying the conditions under which phenotypic plasticity is advantageous. The lack of such a drawdown in unimodal landscapes vs. its dominance in multipeaked landscapes accounts for the seemingly contradictory findings of previous studies.
Epidemiological and aetiological study on tinea pedis and onychomycosis in Algeria
Authors: Djeridane Assya , Djeridane Yasmina , Ammar‐Khodja Aomar
Published: April 2006

Epidemiological studies on tinea pedis and onychomycosis, common fungal infections, have been conducted in many parts of the world. There are currently no studies of tinea pedis and/or onychomycosis in Algeria. The aim of this paper was to study the epidemiology of foot diseases, including tinea pedis and onychomycosis and to identify the aetiological factors of these infections in outpatients attending the Department of Dermatology of the Central Hospital of Army in Algiers, Algeria. A total of 1300 male subjects, mean age 35.9 ± 16 years (range: 16–80) were recruited during the period November 2003 to November 2004 and were clinically examined. A complete dermatological examination was performed on all subjects, and skin and nail specimens of the feet were taken from those patients presenting signs of tinea pedis and/or onychomycosis for microscopy and fungal culture. Clinical diagnosis for tinea pedis and onychomycosis was suspected in 249 and 72 subjects, respectively, and confirmed in 197 and 60 cases, respectively, by positive cultures, resulting in a global prevalence of tinea pedis and toenail onychomycosis of 15% and 4.6% respectively. The age groups most commonly infected were 50–59 and 20–29 years. The yeast species Candida parapsilosis and the dermatophytic species Trichophyton rubrum were shown to be the most common pathogens in both tinea pedis (C. parapsilosis 20.4%; T. rubrum 17%) and onychomycosis (T. rubrum 35%; C. parapsilosis 28.3%). This is the first investigation dealing with fungal foot diseases in Algeria. The clinical and epidemiological data collected would serve as reference for future research and may be useful in the development of preventive and educational strategies.
First case report of empyema caused by Beauveria bassiana
Authors: Gürcan Şaban , Tuğrul H. Murat , Yörük Yener , Özer Burçin , Tatman‐Otkun Müşerref , Otkun Metin
Published: April 2006

Infections with Beauveria bassiana are extremely rare in humans. A 51‐year‐old man was admitted to hospital with the diagnosis of lung adenocarcinoma. Thoracic wall resection with lobectomy was applied and empyema has developed after prolonged air leakage. B. bassiana was isolated in pleural fluid. The patient improved without antifungal therapy after thoracotomy with securing of air leakage.
Antifibrotic effects of tetrandrine on hepatic stellate cells and rats with liver fibrosis
Authors: Hsu Yi‐Chao , Chiu Yung‐Tsung , Cheng Ching‐Chang , Wu Ching‐Fen , Lin Yun‐Lian , Huang Yi‐Tsau
Published: April 2006

Background:  Anti‐inflammation strategies are one of the proposed therapeutic approaches to hepatic fibrosis. Tetrandrine (C38H42O8N2, molecular weight: 622; Tet), an alkaloid isolated from the Chinese medicinal herb Stephania tetrandra, has been shown to exert anti‐inflammatory activity in pulmonary diseases. The purpose of the present study was to investigate the in vitro and in vivo effects of Tet on hepatic fibrosis.

Methods:  A cell line of rat hepatic stellate cells (HSC‐T6) was stimulated with transforming growth factor‐β1 (TGF‐β1) or tumor necrosis factor‐α (TNF‐α). The inhibitory effects of Tet on the nuclear factor κB (NFκB) signaling cascade and molecular markers including intercellular adhesion molecule‐1 (ICAM‐1) and α‐smooth muscle actin (α‐SMA) secretion were assessed. Fibrosis was induced by dimethylnitrosamine (DMN) administration in rats for 4 weeks. Fibrotic rats were randomly assigned to one of the four groups: vehicle (0.7% carboxyl methyl cellulose, CMC), Tet (1 mg/kg), Tet (5 mg/kg), or silymarin (50 mg/kg), each given by gavage twice daily for 3 weeks starting after 1 week of DMN administration. At the end of the study, liver tissues were scored for fibrosis and analyzed for molecular markers of fibrosis.

Results:  Tetrandrine (0.5–5.0 µmol/L) concentration‐dependently inhibited NFκB transcriptional activity induced by TNF‐α, including IκBα phosphorylation and mRNA expressions of ICAM‐1 in HSC‐T6 cells. In addition, Tet also inhibited TGF‐β1‐induced α‐SMA secretion and collagen deposition in HSC‐T6 cells. Fibrosis scores of livers from DMN‐treated rats with high‐dose Tet (1.3 ± 0.3) were significantly reduced in comparison with DMN‐treated rats receiving saline (2.0 ± 0.2). Hepatic collagen content of DMN rats was significantly reduced by either Tet or silymarin treatment. Double‐staining results showed that α‐SMA‐ and NFκB‐positive cells were decreased in the fibrotic livers by Tet and silymarin treatment. In addition, mRNA expression of ICAM‐1, α‐SMA, and TGF‐β1 was attenuated by Tet treatment. Moreover, levels of plasma aspartate aminotransferase and alanine aminotransferase activities were reduced by Tet and silymarin treatment.

Conclusion:  Tetrandrine exerts antifibrotic effects in both HSC‐T6 cells and in rats with DMN‐induced fibrosis.
Akt expression may predict favorable prognosis in cholangiocarcinoma
Authors: Javle Milind M , Yu Jihnhee , Khoury Thaer , Chadha Krishdeep C , Iyer Renuka V , Foster Jason , Kuvshinoff Boris W , Gibbs John F , Geradts Joseph , Black Jennifer D , Brattain Michael G
Published: April 2006

Background:  Overexpression of signaling proteins including epidermal growth factor receptor (EGFR), Akt, mitogen activated protein kinase (MAPK) and cyclooxygenase‐2 (COX‐2) occurs in cholangiocarcinoma cell lines. However, the prognostic value of these markers is unknown. No prior study correlated the expression of these signaling proteins with clinical outcome. Further, co‐expression of these proteins has not been reported. Co‐expression may reflect cross‐talk between signaling pathways. The aim of this clinicopathological study was to investigate the overexpression and co‐expression of EGFR and related signaling proteins in cholangiocarcinoma and explore their relationship to clinical outcome.

Methods:  Twenty‐four consecutive cases of cholangiocarcinoma treated from 1996 to 2002 at Roswell Park Cancer Institute were included. Immunohistochemical staining of paraffin‐embedded tissue sections was performed using antibodies against Akt, p‐Akt, MAPK, p‐MAPK, COX‐2, EGFR and p‐EGFR. Two pathologists independently scored the protein expression.

Results:  Cyclooxygenase‐2, Akt, and p‐MAPK were commonly expressed in biliary cancers (100%, 96% and 87% of malignant cells, respectively). EGFR (60%) and p‐EGFR (22%) overexpression was also detected. There was a significant association between EGFR and p‐EGFR (P = 0.027) and between Akt and p‐Akt (P = 0.017) expression in tumor tissue. A noteworthy association was shown between MAPK and p‐Akt (P = 0.054). Multivariate analysis using the Cox proportional hazard model identified the use of chemotherapy (hazard ratio [HR] = 0.039, P = 0.0002), radiation (HR = 0.176, P = 0.0441) and Akt expression (HR = 0.139, P = 0.006) as the best predictors of overall prognosis.

Conclusion:  Epidermal growth factor receptor signaling intermediates are commonly expressed in cholangiocarcinoma. Expression of Akt and use of systemic chemotherapy or radiation may correlate with improved survival.
Radiotherapy for lymph node metastases in patients with hepatocellular carcinoma: Retrospective study
Authors: Yamashita Hideomi , Nakagawa Keiichi , Shiraishi Kenshiro , Tago Masao , Igaki Hiroshi , Nakamura Naoki , Sasano Nakashi , Siina Shuichiro , Omata Masao , Ohtomo Kuni
Published: April 2006

Aim:  This study was conducted to evaluate the effect of external radiation therapy on lymph node metastases from hepatocellular carcinoma (HCC).

Methods:  A total 28 patients with cytopathologically proven HCC were subjected to radiation therapy over a 5‐year period, and treatment was continued in all cases. All patients underwent irradiation with a total dose ranging between 46 and 60 Gy in daily 2.0‐Gy fractions, five times a week.

Results:  Among the metastatic lesions treated, 18 (64%) and five (18%) patients achieved partial responses and complete responses, respectively. The 1‐ and 2‐year overall survival rates and the median survival time were 53% and 33%, respectively, and 13 months in patients given external beam radiation therapy (EBRT) for a non‐palliative, near‐cure intent (n = 21).

Conclusions:  Although lymph node metastasis from HCC is sensitive to EBRT, the intent of EBRT should be limited to palliation. For palliative purposes, it is useful in treatment with 50 Gy in 25 fractions for these patients.
A null model of temporal trends in biological invasion records
Authors: Wonham Marjorie J. , Pachepsky Elizaveta
Published: April 2006

Biological invasions are a growing aspect of global biodiversity change. In many regions, introduced species richness increases supralinearly over time. This does not, however, necessarily indicate increasing introduction rates or invasion success. We develop a simple null model to identify the expected trend in invasion records over time. For constant introduction rates and success, the expected trend is exponentially increasing. Model extensions with varying introduction rate and success can also generate exponential distributions. We then analyse temporal trends in aquatic, marine and terrestrial invasion records. Most data sets support an exponential distribution (15/16) and the null invasion model (12/16). Thus, our model shows that no change in introduction rate or success need be invoked to explain the majority of observed trends. Further, an exponential trend does not necessarily indicate increasing invasion success or ‘invasional meltdown’, and a saturating trend does not necessarily indicate decreasing success or biotic resistance.
Financial Constraints and Capacity Adjustment: Evidence from a Large Panel of Survey Data
Authors: VON KALCKREUTH ULF
Published: April 2006

The focus of this study is on (i) the interaction between financial constraints and capacity restrictions, and (ii) the difference between large and small firms. Using CBI data to provide information on the financial constraints of UK manufacturers, we develop a new identification scheme based on the link between financial constraints and the prevalence and duration of capacity gaps. Two important results emerge: first, financially constrained firms take longer to close capacity gaps; second, small firms close capacity gaps faster than large firms do, but financial constraints seem to be of greater relevance to their adjustment dynamics.
Ultrastructural features of neurons and synaptic contacts in the posterodorsal medial amygdala of adult male rats
Authors: Hermel E. E. S. , Faccioni‐Heuser M. C. , Marcuzzo S. , Rasia‐Filho A. A. , Achaval M.
Published: April 2006

The aim of the present study was to describe the ultrastructure of neurons (from eight animals) and to analyse the synaptic terminal distribution (from two animals) in the posterodorsal subnucleus of the medial amygdala (MePD) of adult male rats. Using transmission electron microscopy, it was possible to identify many spiny and aspiny dendrites, unmyelinated axonal bundles, single axonal processes, a few myelinated axons, blood vessels and glial processes in the neuropil. Axodendritic synapses were the most frequently observed (67.5%), appearing to be of either the inhibitory or the excitatory types. The presynaptic region contained round or flattened vesicles that occurred either singly or with dense‐cored vesicles (DCVs). The dendrites often received many synapses on a single shaft, and axon terminals displayed synaptic contacts with one or more postsynaptic structures. Dendritic spines showed different morphologies and the synapses on them (23.1%) formed a single and apparently excitatory synaptic contact with round, electron‐lucid vesicles alone or, less frequently, with DCVs. Inhibitory and excitatory axosomatic synapses (8.2%) and excitatory axoaxonic synapses (1.2%) were also identified. The present report provides new findings relevant to the study of the MePD cellular organization and could be combined with other morphological data in order to reveal the functional activity of this area in male rats.
Origin of the styloglossus muscle in the human fetus
Authors: Mérida‐Velasco J. R. , Rodríguez‐Vazquez J. F. , De La Cuadra Blanco C. , Sánchez‐Montesinos I. , Mérida‐Velasco J. A.
Published: April 2006

The origin of the styloglossus muscle was histologically studied bilaterally in nine human fetuses (18 sides). In all cases, the muscle originated in Reichert's cartilage, which gives rise to the temporal styloid process. We identified three types of variation: type A, an accessory muscle fascicle originating from the mandibular angle, found in 7 cases (12 sides); type B, where the styloglossus muscle was attached to the mandibular angle by fibrous tracts, found in three cases (4 sides); and type C, where an accessory muscle fascicle arose from the fibrous tract connecting Reichert's cartilage to the mandibular angle; found in one case. In all cases (2 sides), the styloglossus muscle was innervated by the hypoglossal nerve. Relationships between the styloglossus muscle and vasculonervous elements of the prestyloid and retrostyloid spaces were analysed.
Age‐related impairment of mesenchymal progenitor cell function
Authors: Stolzing Alexandra , Scutt Andrew
Published: April 2006

In most mesenchymal tissues a subcompartment of multipotent progenitor cells is responsible for the maintenance and repair of the tissue following trauma. With increasing age, the ability of tissues to repair themselves is diminished, which may be due to reduced functional capacity of the progenitor cells. The purpose of this study was to investigate the effect of aging on rat mesenchymal progenitor cells. Mesenchymal progenitor cells were isolated from Wistar rats aged 3, 7, 12 and 56 weeks. Viability, capacity for differentiation and cellular aging were examined. Cells from the oldest group accumulated raised levels of oxidized proteins and lipids and showed decreased levels of antioxidative enzyme activity. This was reflected in decreased fibroblast colony‐forming unit (CFU‐f) numbers, increased levels of apoptosis and reduced proliferation and potential for differentiation. These data suggest that the reduced ability to maintain mesenchymal tissue homeostasis in aged mammals is not purely due to a decline in progenitor cells numbers but also to a loss of progenitor functionality due to the accumulation of oxidative damage, which may in turn be a causative factor in a number of age‐related pathologies such as arthritis, tendinosis and osteoporosis.
Patient gender and radiopharmaceutical tracer is of minor importance for the interpretation of myocardial perfusion images using an artificial neural network
Authors: Tägil Kristina , Richard Underwood S. , Davies Glyn , Latus Katherine A. , Ohlsson Mattias , Götborg Cecilia Wallin , Edenbrandt Lars
Published: April 2006

The purpose of this study was to assess the influence of patient gender and choice of perfusion tracer on computer‐based interpretation of myocardial perfusion images. For the image interpretation, an automated method was used based on image processing and artificial neural network techniques. A total of 1000 patients were studied, all referred to the Royal Brompton Hospital in London for myocardial perfusion scintigraphy over a period of 1 year. The patients were randomized to receive either thallium or one of the two technetium tracers, methoxyisobutylisonitrile or tetrofosmin. Artificial neural networks were trained with either mixed gender or gender‐specific and mixed tracer or tracer‐specific training sets of different sizes. The performance of the networks was assessed in separate test sets, with the interpretation of experienced physicians regarding the presence or absence of fixed or reversible defects in the images as the gold standard. The neural networks trained with large mixed gender training sets were as good as the networks trained with gender‐specific data sets. In addition, the neural networks trained with large mixed tracer training sets were as good as or better than the networks trained with tracer‐specific data sets. Our results indicate that the influence of patient gender and perfusion tracer are of minor importance for the computer‐based interpretation of the myocardial perfusion images. The differences that occur can be compensated for by larger training sets.
Steven Lukes on the Concept of Power
Authors: Morriss Peter
Published: April 2006

Steven Lukes has recently reissued his famous book on power, Power: A Radical View. He now admits that the concept of power that he used in his original (1974) book is flawed, but he still wants to defend the position that he advanced there. I argue that he is right to regard his concept of power as flawed, but that admitting this undermines his argument. I conclude that he can rescue his argument by realising that he is not, in fact, using a concept of power at all.
Reversible Palinopsia and the Alice in Wonderland Syndrome Associated With Topiramate Use in Migraineurs
Authors: Evans Randolph W.
Published: April 2006

Two patients are reported who developed palinopsia while taking topiramate for migraine prevention which resolved or decreased in frequency or duration on lower doses, but recurred or increased in frequency or duration on higher doses. Both patients had complete resolution of palinopsia when topiramate was discontinued. A third patient is described who developed the “Alice in Wonderland” syndrome about 1 week after starting topiramate for migraine prevention with complete resolution of symptoms about 1 month after stopping. Topiramate use may cause palinopsia and may be associated with the Alice in Wonderland syndrome through an unknown mechanism.
Interparental Hostility and Early Adolescent Problem Behavior: The Mediating Role of Specific Aspects of Parenting
Authors: Buehler Cheryl , Benson Mark J. , Gerard Jean M.
Published: April 2006

This study examines how parenting helps explain the contemporaneous association between interparental hostility and adolescent problem behavior. A theoretical model of spillover was tested specifying five aspects of mothers' and fathers' parenting that might be associated with parents' hostile interactions with one another: harshness, inconsistency, psychological intrusiveness, and lower levels of acceptance and monitoring knowledge. The sample consisted of 416 early adolescents and their married parents. The association between interparental hostility and adolescent externalizing problems was mediated uniquely by fathers' and mothers' harshness, lower levels of fathers' monitoring knowledge, and mothers' psychological intrusiveness. The association between interparental hostility and adolescent internalizing was mediated uniquely by mothers' harshness, psychological intrusiveness, and lower levels of acceptance. These patterns were similar for sons and daughters.
Trajectories of Perceived Friendship Quality During Adolescence: The Patterns and Contextual Predictors
Authors: Way Niobe , Greene Melissa L.
Published: April 2006

Findings are presented from an ecologically grounded, longitudinal study of 206 urban, ethnic minority adolescents that used hierarchical linear modeling to examine: (1) individual trajectories of change in adolescents' perceptions of general and closest same‐sex friendship quality from middle to late adolescence; (2) the effects of gender and ethnicity on these trajectories of change; and (3) the relative influence of adolescents' perceptions of individual‐level (i.e., self‐esteem) and contextual‐level (i.e., family relationships and school climate) variables on change over time in perceptions of friendship quality. Findings indicated that adolescents' perceptions of the quality of friendships improved from middle to late adolescence. Boys reported sharper increases over time than girls in their perceptions of the quality of their closest, same‐sex friendships. Furthermore, perceptions of contextual level variables (i.e., family relationships, teacher/student relations, and student/student relations) were significantly associated with change over time in perceptions of general and/or closest same‐sex friendship quality.
A Nonlinear Model with Latent Process for Cognitive Evolution Using Multivariate Longitudinal Data
Authors: Proust Cécile , Jacqmin‐Gadda Hélène , Taylor Jeremy M. G. , Ganiayre Julien , Commenges Daniel
Published: April 2006

Summary Cognition is not directly measurable. It is assessed using psychometric tests, which can be viewed as quantitative measures of cognition with error. The aim of this article is to propose a model to describe the evolution in continuous time of unobserved cognition in the elderly and assess the impact of covariates directly on it. The latent cognitive process is defined using a linear mixed model including a Brownian motion and time‐dependent covariates. The observed psychometric tests are considered as the results of parameterized nonlinear transformations of the latent cognitive process at discrete occasions. Estimation of the parameters contained both in the transformations and in the linear mixed model is achieved by maximizing the observed likelihood and graphical methods are performed to assess the goodness of fit of the model. The method is applied to data from PAQUID, a French prospective cohort study of ageing.
Elevated serum erythropoietin levels in patients with Budd‐Chiari syndrome secondary to polycythemia vera: clinical implications for the role of JAK2 mutation analysis
Authors: Thurmes Paul J. , Steensma David P.
Published: April 2006

Abstract:  Purpose: It is widely accepted that an increased serum endogenous erythropoietin (Epo) level in a patient presenting with an elevated red cell mass makes a diagnosis of clonal polycythemia vera (PV) extremely unlikely. However, until the recent description of the constitutively activating V617F point mutation of the Janus 2 tyrosine kinase (JAK2) – a high‐frequency molecular marker that is extremely specific for clonal chronic myeloproliferative disorders – distinction of PV from secondary erythrocytosis or other conditions has often been difficult. The purpose of this study was to use JAK2 V617F analysis to re‐evaluate the validity of elevated Epo levels as a PV‐exclusion criterion in patients with hepatic vein thrombosis [Budd‐Chiari syndrome (BCS)]. Patients and methods: We reviewed clinical data from 30 patients at our institution who presented with erythrocytosis and BCS. We isolated myeloid cells from fresh or archival bone marrow samples from four patients with BCS and an elevated serum Epo level, and analyzed them for the presence of the JAK2 V617F mutation. Results: All four samples were positive for JAK2 V617F, confirming the presence of a clonal hematopoietic disorder consistent with PV. Conclusion: In the presence of BCS, elevated serum Epo levels do not exclude the diagnosis of PV.
Fulminant hepatitis after allogenic bone marrow transplantation caused by reactivation of hepatitis B virus with gene mutations in the core promotor region
Authors: Kitano Kiyoshi , Kobayashi Hikaru , Hanamura Mayu , Furuta Kiyoshi , Ueno Mayumi , Rokuhara Akinori , Tanaka Eiji , Umemura Takeji , Kiyosawa Kendo
Published: April 2006

Abstract:  Under immunosuppressive conditions after hematopoietic stem cell transplantation (HSCT), even if hepatitis B virus (HBV) antigen is negative but hepatitis B surface antibody (HBsAb) or hepatitis B core antibody (HBcAb) is presented, HBV reactivates and sometimes causes fulminant hepatitis. However, it remains unclear which patients will develop fulminant hepatitis, or whether fulminant hepatitis is caused by host‐related factors or by virus‐related factors. A 30‐yr‐old man with a history of aplastic anemia since 3 yr of age underwent allogenic BMT, when HBsAb and HBcAb were positive but HBs antigen (HBsAg) was negative. The donor was negative for HBsAg, HBsAb and HBcAb. After transplantation, the patient was complicated by acute graft‐vs.‐host disease (GVHD), cytomegalovirus infection, intestinal thrombotic microangiopathy and aspergillus colitis. Chronic GVHD was well controlled by FK506 and prednisolone. Twenty months after transplantation, the patient was admitted with general fatigue and liver dysfunction and was found to be positive for HBsAg and HBeAg. His serum HBV‐DNA level was >8.8 log of the genome equivalent (LGE)/mL. Therefore, he was diagnosed as having hepatitis B caused by HBV reactivation and 100 mg/d lamivudine treatment was started. However, jaundice and hepatic failure deteriorated and became fatal. On analysis of the HBV‐DNA, two adjacent gene mutations in the core promoter region (T1762/A1764) were detected. Increased replication of the mutated HBV might have caused HBV reactivation which progressed to fulminant hepatitis.
A comparative ex vivo and in vivo study of day and night perception in teleosts species using the melatonin rhythm
Authors: Migaud H. , Taylor J.F. , Taranger G.L. , Davie A. , Cerdá‐Reverter J.M. , Carrillo M. , Hansen T. , Bromage N.R.
Published: April 2006

Abstract:  The purpose of this study was to determine and compare the light sensitivity of two commercially important, phylogenetically different teleost species in terms of melatonin production. Three series of experiments were performed on both Atlantic salmon and European sea bass. First, a range of light intensities were tested ex vivo on pineal melatonin production in culture during the dark phase. Then, light transmission through the skull was investigated, and finally short‐term in vivo light sensitivity trials were performed. Results showed that sea bass pineal gland ex vivo are at least 10 times more sensitive to light than that of the salmon. Light intensity threshold in sea bass appeared to be between 3.8 × 10−5 and 3.8 × 10−6 W/m2 in contrast to 3.8 × 10−4 and 3.8 × 10−5 W/m2 in salmon. These highlighted species‐specific light sensitivities of pineal melatonin production that are likely to be the result of adaptation to particular photic niches. Light transmission results showed that a significantly higher percentage of light penetrates the sea bass pineal window relative to salmon, and confirmed that penetration is directly related to wavelength with higher penetration towards the red end of the visible spectrum. Although results obtained in vivo were comparable, large differences between ex vivo and in vivo were observed in both species. The pineal gland in isolation thus appeared to have different sensitivities as the whole animal, suggesting that retinal and/or deep brain photoreception may contribute, in vivo, to the control of melatonin production.
Dendritic pathology in mental retardation: from molecular genetics to neurobiology
Authors: Dierssen M. , Ramakers G. J. A.
Published: April 2006

Mental retardation (MR) is a developmental brain disorder characterized by impaired cognitive performance and adaptive skills that affects 1–2% of the population. During the last decade, a large number of genes have been cloned that cause MR upon mutation in humans. The causal role of these genes provides an excellent starting point to investigate the cellular, neurobiological and behavioral alterations and mechanisms responsible for the cognitive impairment in mentally retarded persons. However, studies on Down syndrome (DS) reveal that overexpression of a cluster of genes and various forms of MR that are caused by single‐gene mutations, such as fragile X (FraX), Rett, Coffin‐Lowry, Rubinstein–Taybi syndrome and non‐syndromic forms of MR, causes similar phenotypes. In spite of the many differences in the manifestation of these forms of MR, evidence converges on the proposal that MR is primarily due to deficiencies in neuronal network connectivity in the major cognitive centers in the brain, which secondarily results in impaired information processing. Although MR has been largely regarded as a brain disorder that cannot be cured, our increased understanding of the abnormalities and mechanisms underlying MR may provide an avenue for the development of therapies for MR. In this review, we discuss the neurobiology underlying MR, with a focus on FraX and DS
ASSOCIATION BETWEEN CLINICAL CHARACTERISTICS, COMPUTED TOMOGRAPHY CHARACTERISTICS, AND HISTOLOGIC DIAGNOSIS FOR CATS WITH SINONASAL DISEASE
Authors: TROMBLEE TONYA C. , JONES JERYL C. , ETUE ASHLEY E. , DRU FORRESTER S.
Published: April 2006

The purpose of this retrospective study was to determine the association between clinical characteristics, computed tomography (CT) characteristics, and histologic diagnosis in 43 cats with sinonasal disease. All cats were evaluated with CT and nasopharyngeal endoscopic examination, with histologic diagnosis based on nasal biopsy. Fifteen cats were diagnosed with sinonasal neoplasia and 28 cats were diagnosed with rhinitis. Clinical characteristics determined to be significantly associated with neoplasia were unilateral ocular discharge (odds ratio [OR] 9.6) and the presence of a nasopharyngeal mass during endoscopic examination (OR 18.9). CT characteristics found to be significantly associated with neoplasia included: unilateral lysis of ethmoturbinates (OR 11.0), unilateral lysis of the dorsal (OR 8.3) and lateral maxilla (OR 6.9), lysis of the vomer bone (OR 6.7) and ventral maxilla (OR 28.8), and bilateral lysis of the orbital lamina (OR 4.1); unilateral abnormal soft tissue/fluid within the sphenoid sinus (OR 15.3), frontal sinus (OR 10.4), and/or and retrobulbar space (OR 12.2). Lysis of the maxillary turbinates, nasal septum, nasal bone, palatine bone, and cribriform plate were not significantly associated with sinonasal neoplasia.
Vegas Stripped
Authors: Eadington William
Published: April 2006

Las Vegas is the casino capital of the world. Millions of gamblers and billions of dollars pass through its glittering, neon-lit attractions. How does it operate? Where, if anywhere, are the odds in the gambler's favour? From blackjack to the high-technology slot machines that have replaced the old-time one-armed bandits, Bill Eadington examines probabilities, prices and casino games on offer both on and off the Las Vegas strip and tells us how and where to gain most—or, more accurately, to lose least—in Las Vegas.
Read All About It?
Authors: Forrest David , Simmons Robert
Published: April 2006

If statistics are of little help in predicting individual football results, are the professional followers of the sport any better? David Forrest and Robert Simmons analyse the performance of newspaper tipsters in helping the gambler to beat the bookies.
Reflections on the UK National Lottery
Authors: Haigh John
Published: April 2006

Gambling in Britain has been transformed by the National Lottery. The small pink ticket from the newsagent's electronic outlet offers temptation of wealth beyond the dreams of avarice. John Haigh examines a bet that, statistically, not one of our readers will live to win.
Wild Card
Authors: Diaconis Persi
Published: April 2006

In 1992 Persi Diaconis of Stanford University told the world just how many times a pack of cards should be shuffled. He is one of the more colourful of professors of statistics. He tells Julian Champkin about crooked dice, tossing coins and conjuring tricks—and how statistics makes sense of his world.