bluuebunny/crossref_metadata_2025 huggingface dataset:
Mitogenetic structure of brown bears (Ursus arctos L.) in northeastern Europe and a new time frame for the formation of European brown bear lineages
Authors: SAARMA URMAS , HO SIMON Y. W. , PYBUS OLIVER G. , KALJUSTE MARJU , TUMANOV IGOR L. , KOJOLA ILPO. , VOROBIEV ALEX A. , MARKOV NIKOLAI I. , SAVELJEV ALEXANDER P. , VALDMANN HARRI , LYAPUNOVA ELENA A. , ABRAMOV ALEXEI V. , MÄNNIL PEEP. , KORSTEN MARJU , VULLA EGLE. , PAZETNOV SERGEI V. , PAZETNOV VALENTIN S. , PUTCHKOVSKIY STANISLAV V. , RÕKOV ALEXANDER M.
Published: November 2006

We estimated the phylogenetic relationships of brown bear maternal haplotypes from countries of northeastern Europe (Estonia, Finland and European Russia), using sequences of mitochondrial DNA (mtDNA) control region of 231 bears. Twenty‐five mtDNA haplotypes were identified. The brown bear population in northeastern Europe can be divided into three haplogroups: one with bears from all three countries, one with bears from Finland and Russia, and the third composed almost exclusively of bears from European Russia. Four haplotypes from Finland and European Russia matched exactly with haplotypes from Slovakia, suggesting the significance of the current territory of Slovakia in ancient demographic processes of brown bears. Based on the results of this study and those from the recent literature, we hypothesize that the West Carpathian Mountains have served either as one of the northernmost refuge areas or as an important movement corridor for brown bears of the Eastern lineage towards northern Europe during or after the last ice age. Bayesian analyses were performed to investigate the temporal framework of brown bear lineages in Europe. The molecular clock was calibrated using Beringian brown bear sequences derived from radiocarbon‐dated ancient samples, and the estimated mutation rate was 29.8% (13.3%−47.6%) per million years. The whole European population and Western and Eastern lineages formed about 175 000, 70 000 and 25 000 years before present, respectively. Our approach to estimating the time frame of brown bear evolution demonstrates the importance of using an appropriate mutation rate, and this has implications for other studies of Pleistocene populations.
Characterization of the OxyR regulon of Neisseria gonorrhoeae
Authors: Seib Kate L. , Wu Hsing‐Ju , Srikhanta Yogitha N. , Edwards Jennifer L. , Falsetta Megan L. , Hamilton Amanda J. , Maguire Tina L. , Grimmond Sean M. , Apicella Michael A. , McEwan Alastair G. , Jennings Michael P.
Published: November 2006

OxyR regulates the expression of the majority of H2O2 responses in Gram‐negative organisms. In a previous study we reported the OxyR‐dependent derepression of catalase expression in the human pathogen Neisseria gonorrhoeae. In the present study we used microarray expression profiling of N. gonorrhoeae wild‐type strain 1291 and an oxyR mutant strain to define the OxyR regulon. In addition to katA (encoding catalase), only one other locus displayed a greater than two‐fold difference in expression in the wild type : oxyR comparison. This locus encodes an operon of two genes, a putative peroxiredoxin/glutaredoxin (Prx) and a putative glutathione oxidoreductase (Gor). Mutant strains were constructed in which each of these genes was inactivated. A previous biochemical study in Neisseria meningitidis had confirmed function of the glutaredoxin/peroxiredoxin. Assay of the wild‐type 1291 cell free extract confirmed Gor activity, which was lost in the gor mutant strain. Phenotypic analysis of the prx mutant strain in H2O2 killing assays revealed increased resistance, presumably due to upregulation of alternative defence mechanisms. The oxyR, prx and gor mutant strains were deficient in biofilm formation, and the oxyR and prx strains had decreased survival in cervical epithelial cells, indicating a key role for the OxyR regulon in these processes.
Substitutions in the N‐terminal alpha helical spine of Neisseria gonorrhoeae pilin affect Type IV pilus assembly, dynamics and associated functions
Authors: Aas Finn Erik , Winther‐Larsen Hanne C. , Wolfgang Matthew , Frye Stephan , Løvold Cecilia , Roos Norbert , Van Putten Jos P. M. , Koomey Michael
Published: November 2006

Type IV pili (Tfp) are multifunctional surface appendages expressed by many Gram negative species of medical, environmental and industrial importance. The N‐terminally localized, so called α‐helical spine is the most conserved structural feature of pilin subunits in these organelles. Prevailing models of pilus assembly and structure invariably implicate its importance to membrane trafficking, organelle structure and related functions. Nonetheless, relatively few studies have examined the effects of missense substitutions within this domain. Using Neisseria gonorrhoeae as a model system, we constructed mutants with single and multiple amino acid substitutions localized to this region of the pilin subunit PilE and characterized them with regard to pilin stability, organelle expression and associated phenotypes. The consequences of simultaneous expression of the mutant and wild‐type PilE forms were also examined. The findings document for the first time in a defined genetic background the phenomenon of pilin intermolecular complementation in which assembly defective pilin can be rescued into purifiable Tfp by coexpression of wild‐type PilE. The results further demonstrate that pilin subunit composition can impact on organelle dynamics mediated by the PilT retraction protein via a process that appears to monitor the efficacy of subunit–subunit interactions. In addition to confirming and extending the evidence for PilE multimerization as an essential component for competence for natural genetic transformation, this work paves the way for detailed studies of Tfp subunit–subunit interactions including self‐recognition within the membrane and packing within the pilus polymer.
A family of stage‐specific alanine‐rich proteins on the surface of epimastigote forms of Trypanosoma brucei
Authors: Urwyler Simon , Studer Erwin , Renggli Christina Kunz , Roditi Isabel
Published: November 2006

A ‘two coat’ model of the life cycle of Trypanosoma brucei has prevailed for more than 15 years. Metacyclic forms transmitted by infected tsetse flies and mammalian bloodstream forms are covered by variant surface glycoproteins. All other life cycle stages were believed to have a procyclin coat, until it was shown recently that epimastigote forms in tsetse salivary glands express procyclin mRNAs without translating them. As epimastigote forms cannot be cultured, a procedure was devised to compare the transcriptomes of parasites in different fly tissues. Transcripts encoding a family of glycosylphosphatidyl inositol‐anchored proteins, BARPs (previously called bloodstream alanine‐rich proteins), were 20‐fold more abundant in salivary gland than midgut (procyclic) trypanosomes. Anti‐BARP antisera reacted strongly and exclusively with salivary gland parasites and a BARP 3′ flanking region directed epimastigote‐specific expression of reporter genes in the fly, but inhibited expression in bloodstream and procyclic forms. In contrast to an earlier report, we could not detect BARPs in bloodstream forms. We propose that BARPs form a stage‐specific coat for epimastigote forms and suggest renaming them brucei alanine‐rich proteins.
Clostridium taeniosporum spore ribbon‐like appendage structure, composition and genes
Authors: Walker James R. , Gnanam Annie J. , Blinkova Alexandra L. , Hermandson Mary Jo , Karymov Mikhail A. , Lyubchenko Yuri L. , Graves Paul R. , Haystead Timothy A. , Linse Klaus D.
Published: November 2006

Clostridium taeniosporum spores have about 12 large, flat, ribbon‐like appendages attached through a common trunk at one spore pole to a previously unknown surface layer outside the coat that is proposed to be called the ‘encasement’. Appendages are about 4.5 μm long, 0.5 μm wide and 30 nm thick and taper at the attachment end into a semicircle that is twisted relative to the flat ribbon. Individual fibrils, about 45 nm in length with spherical heads and long thin tails, form a hair‐like nap, visible along the appendage edge. Four appendage proteins have been detected: a paralogous pair of 29 kDa (designated P29a and P29b), a glycoprotein of about 37 kDa (designated GP85) and an orthologue of the Bacillus spore morphogenetic protein SpoVM. The P29 proteins consist of duplicated regions and each region includes a domain of unknown function 11. The GP85 glycoprotein contains a collagen‐like region. The genes for P29a and b, GP85 and possibly related proteins are closely linked on two small chromosome fragments. Putative σK‐dependent promoters upstream of the P29a and b genes indicate that they likely are expressed late in the mother cell, consistent with their deposition into the layer external to the coat.
Subcellular positioning of the origin region of the Bacillus subtilis chromosome is independent of sequences within oriC, the site of replication initiation, and the replication initiator DnaA
Authors: Berkmen Melanie B. , Grossman Alan D.
Published: November 2006

Regions of bacterial chromosomes occupy characteristic locations within the cell. In Bacillus subtilis, the origin of replication, oriC, is located at 0°/360° on the circular chromosome. After duplication, sister 0° regions rapidly move to and then reside near the cell quarters. It has been hypothesized that origin function or oriC sequences contribute to positioning and movement of the 0° region. We found that the position of a given chromosomal region does not depend on initiation of replication from the 0° region. In an oriC mutant strain that replicates from a heterologous origin (oriN) at 257°, the position of both the 0° and 257° regions was similar to that in wild‐type cells. Thus, positioning of chromosomal regions appears to be independent of which region is replicated first. Furthermore, we found that neither oriC sequences nor the replication initiator DnaA is required or sufficient for positioning a region near the cell quarters. A sequence within oriC previously proposed to play a critical role in chromosome positioning and partitioning was found to make little, if any, contribution. We propose that uncharacterized sites outside of oriC are involved in moving and/or maintaining the 0° region near the cell quarters.
Acid pH activation of the PmrA/PmrB two‐component regulatory system of Salmonella enterica
Authors: Perez J. Christian , Groisman Eduardo A.
Published: November 2006

Acid pH often triggers changes in gene expression. However, little is known about the identity of the gene products that sense fluctuations in extracytoplasmic pH. The Gram‐negative pathogen Salmonella enterica serovar Typhimurium experiences a number of acidic environments both inside and outside animal hosts. Growth in mild acid (pH 5.8) promotes transcription of genes activated by the response regulator PmrA, but the signalling pathway(s) that mediates this response has thus far remained unexplored. Here we report that this activation requires both PmrA's cognate sensor kinase PmrB, which had been previously shown to respond to Fe3+ and Al3+, and PmrA's post‐translational activator PmrD. Substitution of a conserved histidine or of either one of four conserved glutamic acid residues in the periplasmic domain of PmrB severely decreased or abolished the mild acid‐promoted transcription of PmrA‐activated genes. The PmrA/PmrB system controls lipopolysaccharide modifications mediating resistance to the antibiotic polymyxin B. Wild‐type Salmonella grown at pH 5.8 were > 100 000‐fold more resistant to polymyxin B than organisms grown at pH 7.7. Our results suggest that protonation of the PmrB periplasmic histidine and/or of the glutamic acid residues activate the PmrA protein, and that mild acid promotes cellular changes resulting in polymyxin B resistance.
Immunomodulatory Role of Chloroquine and Pyrimethamine in Plasmodium yoelii 17XL Infected Mice
Authors: Ramos‐Avila A. , Ventura‐Gallegos J. L. , Zentella‐Dehesa A. , Machuca‐Rodríguez C. , Moreno‐Altamirano M. M. , Narváez V. , Legorreta‐Herrera M.
Published: November 2006

Chloroquine (CLQ) and Pyrimethamine (PYR) are used for the treatment of malaria and some autoimmune diseases; although their mechanism of action is only partially understood, their therapeutic effectiveness in the second case has been attributed to their ability to increase apoptosis of T lymphocytes. In view of the potential for immunomodulation during malaria chemotherapy, we investigated the effects of CLQ and PYR treatment on lymphocyte apoptosis and cytokine expression during infection with blood‐stage Plasmodium. This work shows that infection of BALB/c mice with Plasmodium yoelii 17XL (Py17XL) reduced apoptosis in spleen cells but when infected mice were treated with CLQ, apoptosis of B and T lymphocytes increased significantly via a Fas‐mRNA expression independent mechanism associated with downregulation of Bcl‐2 expression, whereas treatment with PYR increased apoptosis to a lesser extent and only in B lymphocytes. CLQ treatment of Py17XL infected mice upregulated tumour necrosis factor‐α mRNA expression, while PYR treatment increased interferon‐γ mRNA expression. In infected mice, treatment with CLQ downregulated expression of the anti‐inflammatory cytokines, interleukin‐10 and transforming growth factor‐β (TGF‐β), while PYR treatment upregulated TGF‐β. Thus, in addition to their anti‐malarial effects, both drugs modulate the immune response in malaria by increasing apoptosis and modulating the mRNA expression of cytokines involved in parasite elimination and regulation of inflammatory responses.
Autoantibody‐mediated Bladder Dysfunction in Type 1 Diabetes
Authors: Wan E.‐C. , Gordon T. P. , Jackson M. W.
Published: November 2006

Bladder dysfunction is a common complication of diabetic autonomic neuropathy; however, its cause remains uncertain. We have recently identified a novel IgG autoantibody (Ab) in patients with type 1 diabetes that acts as an agonist at the dihydropyridine (DHP) site of L‐type voltage‐gated calcium channels (VGCC), disrupting neuronal regulation of visceral smooth muscle. In the present study, passive transfer to mice of IgG from patients with type 1 diabetes was used to investigate the role of anti‐VGCC Abs in mediating diabetic bladder dysfunction. Injection of mice with diabetic immunoglobulin (IgG) with anti‐VGCC activity induced features of an overactive bladder, including phasic detrusor contractions and a loss of bladder wall compliance. The bladder overactivity is mimicked by the DHP agonist Bay K8644, reversed by the DHP antagonist nicardipine, but is insensitive to the motor nerve blocker tetrodotoxin, indicating that the anti‐VGCC Ab acts at the level of the bladder detrusor itself. This study reports the first evidence of Ab‐mediated bladder dysfunction in type 1 diabetes, which may be part of a wider spectrum of smooth muscle and cardiac abnormalities.
Control of FWA gene silencing in Arabidopsis thaliana by SINE‐related direct repeats
Authors: Kinoshita Yuki , Saze Hidetoshi , Kinoshita Tetsu , Miura Asuka , Soppe Wim J.J. , Koornneef Maarten , Kakutani Tetsuji
Published: November 2006

A unique feature of late‐flowering fwa epigenetic mutations is that the phenotype is caused by ectopic expression of the homeobox gene FWA. During normal development the FWA gene is expressed specifically in the endosperm in an imprinted manner. Ectopic FWA expression and disruption of imprinting can be induced in mutants of a CG methyltransferase MET1 (methyltransferase 1) or a chromatin‐remodeling gene DDM1 (decrease in DNA methylation 1), suggesting that the proper FWA expression depends on cytosine methylation. However, critical methylated residues controlling FWA silencing are not pinpointed. Nor is it understood how the FWA gene is initially methylated and silenced in wild‐type plants. Here we mapped sequences critical for FWA silencing by application of RdDM (RNA‐directed DNA methylation) to a ddm1‐induced stable fwa epiallele. Transcription of double‐stranded RNA corresponding to the tandem direct repeats around the FWA transcription start site induced de novo DNA methylation, transcriptional suppression and phenotypic reversion. The induced changes were heritable even without the transgene, which correlates with inheritance of CG methylation in the direct repeats. The newly silenced FWA allele was transcribed in an endosperm‐specific and imprinted manner, as is the case for the wild‐type FWA gene. The results indicate that methylation of the direct repeats, which presumably originated from a short interspersed nuclear element (SINE), is sufficient to induce proper epigenetic control of the FWA gene.
The rice heterochronic gene SUPERNUMERARY BRACT regulates the transition from spikelet meristem to floral meristem
Authors: Lee Dong‐Yeon , Lee Jinwon , Moon Sunok , Park Soung Young , An Gynheung
Published: November 2006

Regulating the transition of meristem identity is a critical step in reproductive development. After the shoot apical meristem (SAM) acquires inflorescence meristem identity, it goes through a sequential transition to second‐ and higher‐order meristems that can eventually give rise to floral organs. Despite ample information on the molecular mechanisms that control the transition from SAM to inflorescence meristems, little is known about the mechanism for inflorescence development, especially in monocots. Here, we report the identification of the SUPERNUMERARY BRACT (SNB) gene controlling the transition from spikelet meristem to floral meristem and the floral organ development. This gene encodes a putative transcription factor carrying two AP2 domains. The SNB:GFP fusion protein is localized to the nucleus. SNB is expressed in all the examined tissues, but most strongly in the newly emerging spikelet meristems. In SNB knockout plants, the transition from spikelet meristems to floral meristems is delayed, resulting in the production of multiple rudimentary glumes in an alternative phyllotaxy. The development of additional bracts interferes with subsequent floral architecture. In some spikelets, the empty glumes and lodicules are transformed into lemma/palea‐like organs. Occasionally, the number of stamens and carpels is altered and an ectopic floret occurs in the axil of the rachilla. These phenotypes suggest that snb is a heterochronic mutant, affecting the phase transition of spikelet meristems, the pattern formation of floral organs and spikelet meristem determinancy.
Bacterial risk reduction by improved donor arm disinfection, diversion and bacterial screening
Authors: McDonald C. P.
Published: November 2006

summary The Interventions of improved donor arm disinfection, diversion and bacterial screening have been implemented by blood services and shown to have substantial benefit. The major source of bacterial contamination is donor arm derived. Blood services are now introducing best practice donor arm disinfection techniques.

Diversion has been shown to substantially reduce bacterial contamination in the order of 40–88%. Diversion, together with improved donor arm disinfection, has shown to improve the percentage of reduction in contamination from 47% to 77%. Residual contamination levels after the Introduction of diversion and improved donor arm disinfection may be in the order of 30–40%. Numerous countries have now implemented screen testing programmes for platelet concentrates, which are the major source of bacterial transfusion transmission.

Pathogen reduction systems have been developed and are under development. At present, concerns remain with these systems regarding cost, process control, ability to inactivate high titres of viruses, killing of bacterial spores, product damage, genotoxicity and mutagenicity.

The interventions of diversion, improved donor arm disinfection and bacterial screen testing are currently available, As such they can be implemented now to increase blood safety with no associated patient risk.
Revaccination with Bacillus Calmette‐Guerin (BCG) vaccine does not reduce morbidity from malaria in African children
Authors: Rodrigues Amabelia , Schellenberg Joanna Armstrong , Roth Adam , Benn Christine Stabell , Aaby Peter , Greenwood Brian
Published: November 2006

Background  Studies in West Africa and elsewhere have suggested that Bacillus Calmette‐Guérin (BCG) vaccine given at birth is beneficial for child survival. It is possible that this effect is mediated partly through an effect on malaria, a hypothesis supported by animal studies. We investigated whether revaccination with BCG at 19 months of age reduced morbidity from malaria.

Method  In the capital of Guinea‐Bissau, between January and November 2003, children who had previously received BCG vaccination and who did not have a strong reaction to tuberculin were individually randomised to either receive revaccination with BCG at the age of 19 months or to be a control. Episodes of malaria were recorded during the 2003 malaria transmission season through passive case detection at health centres in the study area and at the national hospital. Cross‐sectional surveys were carried out at the beginning and at the end of the rainy season.

Results  Incidence rates of first episodes of malaria associated with any level of parasitaemia were 0.16 episodes per child‐year among 713 revaccinated children and 0.12 among 720 control children [incidence rate ratio (IRR) = 1.37; 95% confidence intervals (CI): 0.84–2.25]. Results were similar when the diagnosis of malaria was based on the presence of parasitaemia >5000 parasites/μl (IRR = 1.30; 95% CI: 0.61–2.77). The incidence of all‐cause hospitalisation was higher among BCG‐revaccinated children than among controls (IRR = 2.13; 95% CI: 1.10–4.13). There were no significant differences in the prevalence of parasitaemia between the two groups of children at cross‐sectional surveys.

Conclusion  We found no evidence that BCG revaccination reduces morbidity from malaria.
Quality control of active ingredients in artemisinin‐derivative antimalarials within Kenya and DR Congo
Authors: Atemnkeng Magnus A. , De Cock Katelijne , Plaizier‐Vercammen Jacqueline
Published: November 2006

Objectives  Artemisinin‐derivative drugs are widely used to treat Plasmodium falciparum malaria and very few studies have investigated the quality of these medicines in Africa. We analysed the active ingredient contents of artemisinin‐derivative drugs marketed in Kenya and DR Congo.

Methods  We analysed tablets, capsules, dry suspensions and injections (IM) containing either artemether (AM), arteether (AE), artesunate (ARS) or dihydroartemisinin (DHA). The content of active ingredients and preservatives was determined quantitatively using validated HPLC‐UV methods. All analyses were done according to European pharmacopoeia requirements.

Results  Labelled active ingredients were identified in all samples, however with varying dosages. Nine of the 24 drug samples analysed did not comply with the pharmacopoeial requirements of 95–105%: seven samples were underdosed and two were slightly overdosed. DHA was the active ingredient in 57% of the underdosed samples. AE injections had the lowest drug content (77%). Two‐thirds of the dry powder suspensions were either substandard or fake. Tablets were up to 23% out of range. Unidentified peaks were observed on the chromatograms of AE IM injections and a DHA dry powder.

Conclusions  Counterfeit or substandard artemisinin‐derivative drugs are being sold in parts of Africa, presenting a potential route for resistance development in the future. Appropriate measures need to be taken to maintain proper and safe use of these medicines.
Survival bias in observational studies of the impact of routine immunizations on childhood survival
Authors: Jensen Henrik , Benn Christine Stabell , Lisse Ida Maria , Rodrigues Amabelia , Andersen Per Kragh , Aaby Peter
Published: November 2006

Objectives  In situations with vaccination coverage high enough to control pertussis, observational studies have reported divergent effects of diphtheria–tetanus–pertussis (DTP) vaccination on childhood survival. We examined whether this could be because of methodological differences.

Methods  Some studies of the impact of DTP updated information on vaccination retrospectively (retrospective updating approach) while others kept vaccination status fixed for the time between follow‐up visits (landmark approach). First, we conducted simulations with these approaches to investigate the impact of different mortality levels, vaccination incidence rates, intervals between data collection visits, and the proportion of children whose vaccination card had not been seen after death. Second, we re‐analysed data from Guinea‐Bissau using the retrospective updating approach.

Results  In simulations, the retrospective updating approach produced rate ratio (vaccinated/unvaccinated) estimates biased towards zero because of a differential misclassification which created survival bias as risk‐free observation time was allocated to the vaccinated group. The landmark approach produced rate ratio estimates biased towards one. Biases increased with interval between data collection visits and incidence of vaccination, but were unaffected by the underlying mortality level. Survival bias increased with the proportion of dead children whose vaccination status could not be updated. The re‐analysis of data from Guinea‐Bissau changed the estimated impact of DTP from an 84% higher mortality using the landmark approach to a 37% lower mortality using the retrospective updating approach.

Conclusions  The apparent contradiction between DTP studies could be because of methodological differences. To assess child survival associated with routine vaccinations, studies minimizing the effect of biases are warranted.
A biological test to quantify pyrethroid in impregnated nets
Authors: Martin T. , Chandre F. , Chabi J. , Guillet P. F. , Akogbeto M. , Hougard J. M.
Published: November 2006

First instar larvae of Aedes aegypti (L.) (Diptera: Culicidae) are very susceptible to deltamethrin, which kills all larvae at a very low dose (0.1 μg/l). Thus the sensitivity of this insect to detect that pyrethroid is in parts per billion, as obtained with most common chromatographic methods of analysis. Here we describe a biological test (BT) to quantify deltamethrin in long‐lasting insecticidal nets (LLINs) by exposing first instar larvae of Ae. aegypti to serial extracted insecticide solutions from net samples. The deltamethrin concentration in the net was calculated at the doses killing 50% of larva, from the LC50 of deltamethrin (6.5 × 10−5 mg/l) and the dilution factor (DF50) of the extracted net solution. The pyrethroid quantification in LLINs after 0–25 washes with this BT was correlated with those obtained by direct chromatographic analysis (r2 = 0.84). This BT did not require sophisticated equipment and could be extended to other molecules and materials. It appeared accurate, robust, cheap and well adapted to the national malaria programmes as the eggs of Ae. aegypti might be used for some months. This method was adapted to provide an easy to use kit test for the quality control of LLINs in the field.
Is molecular biology the best alternative for diagnosis of malaria to microscopy? A comparison between microscopy, antigen detection and molecular tests in rural Kenya and urban Tanzania
Authors: Mens P. , Spieker N. , Omar S. , Heijnen M. , Schallig H. , Kager P. A.
Published: November 2006

Objective  To assess the agreement of different diagnostic methods for the diagnosis and confirmation of the clinical suspicion of Plasmodium infection in children in Tanzania and Kenya.

Method  Blood samples were collected by the finger prick method from 338 children. Blood samples were collected from 338 children with the clinical suspicion of uncomplicated malaria in health clinics in Tanzania and Kenya. The presence of Plasmodium parasites was assessed with microscopy, rapid diagnostic tests (RDTs) and the molecular assays, quantitative nucleic acid sequence based amplification (QT‐NASBA) and polymerase chain reaction (PCR). The results were compared and analysed for agreement.

Results  There was a high degree of agreement (88.6–100%) between RDTs or molecular tests and microscopy. In rural Kenya, with a high incidence of malaria cases, the correlation coefficient ranged from 0.94 for RDTs to 0.76 for PCR. In urban Tanzania, where there was a low incidence of cases, R for RDTs was 1.0 but only 0.25 for PCR and 0.33 for NASBA.

Conclusion  Malaria is overestimated if the diagnosis is based solely on clinical signs. Therefore, laboratory confirmation is essential. Microscopy is a reliable method in rural areas where malaria is prevalent, but RDTs offer a good alternative with the advantage that it is an easy and rapid method. Molecular tests are more sensitive but difficult to implement in rural areas. In areas with lower incidence, molecular tests detect a significantly higher number of Plasmodium infections than RDTs or microscopy. Although implementation of molecular tools can be difficult, the prospect of an easy and cheap detection system makes them promising tools for the near future.
Diagnosis and management of early‐ and late‐onset cerebellar ataxia
Authors: Brusse E , Maat‐Kievit JA , Van Swieten JC
Published: November 2006

Cerebellar ataxias represent a heterogeneous group of neurodegenerative disorders. Two main categories are distinguished: hereditary and sporadic ataxias. Sporadic ataxias may be symptomatic or idiopathic. The clinical classification of hereditary ataxias is nowadays being replaced by an expanding genotype‐based classification. A large spectrum of degenerative and metabolic disorders may also present with ataxia early or late in the course of disease. We present a diagnostic algorithm for the adult patient presenting with subacute cerebellar ataxia, based on family history and straightforward clinical characteristics of the patient. Along with the algorithm, an overview of the autosomal dominant, autosomal recessive, X‐linked, mitochondrial, symptomatic and idiopathic subtypes of cerebellar ataxia is presented. An appropriate diagnosis is of utmost importance to such considerations as prognosis, genetic counselling and possible therapeutic implications.
Safety and efficacy of prolonged cytomegalovirus prophylaxis with intravenous ganciclovir in pediatric and young adult lung transplant recipients
Authors: Spivey John F. , Singleton Dana , Sweet Stuart , Storch Gregory A. , Hayashi Robert J. , Huddleston Charles B. , Danziger‐Isakov Lara A.
Published: November 2006

Abstract:  CMV infection causes morbidity and mortality after transplantation. Despite a wide range of prevention strategies among pediatric lung transplant programs, the optimal duration of prophylactic therapy against CMV infection in pediatric lung transplantation is unknown. To assess the feasibility, safety, and short‐term efficacy of extending intravenous ganciclovir administration from six wk duration to 12 wk duration in pediatric lung transplant recipients. An open‐label pilot study was performed in primary pediatric lung transplant recipients with donor and/or recipient CMV seropositivity. Intravenous ganciclovir was given for 12 wk post‐transplantation. Subjects were tracked for protocol completion. Toxicities monitored included renal dysfunction, myelosuppression, gastrointestinal and neurological complications, as well as infection related to indwelling catheter placement. Serial CMV levels were measured to determine short‐term efficacy of the intervention. Nine of nine subjects enrolled completed the pilot study. Subjects’ ages ranged from six to 18 yr. Indications for lung transplantation included cystic fibrosis (n = 7), idiopathic pulmonary hypertension (n = 1), and complex congenital heart disease with pulmonary hypertension (n = 1). Seven subjects underwent deceased donor bilateral lung transplantation and two subjects underwent heart–lung transplantation. No subjects had protocol‐defined drug toxicity. No episodes of neutropenia, thrombocytopenia, or renal toxicity occurred. Five subjects had catheter‐related infections (three after week 12 of ganciclovir). Seven of nine subjects had CMV detected by PCR (four prior to ganciclovir completion) with only one subject having a positive viral culture for CMV viremia (prior to ganciclovir completion). No subjects had UL‐97 mutation for ganciclovir resistance detected. The use of prolonged prophylactic administration of ganciclovir for 12 wk duration is a feasible, safe, and effective treatment to prevent CMV viremia based on viral culture in at risk pediatric lung transplant recipients. Further clinical studies are underway to determine optimal CMV prevention strategies.
Health insurance considerations for adolescent transplant recipients as they transition to adulthood
Authors: Willoughby Lisa M. , Fukami Sumina , Bunnapradist Suphamai , Gavard Jeffrey A. , Lentine Krista L. , Hardinger Karen L. , Burroughs Thomas E. , Takemoto Steven K. , Schnitzler Mark A.
Published: November 2006

Abstract:  The advent of improved immunosuppression and enhanced allograft outcomes has resulted in a growing number of patients taking expensive immunosuppression medications for the rest of their lives. Healthcare costs for the majority of transplantation procedures in the USA currently are covered by Medicare, but coverage ends for outpatient immunosuppression medications 36–44 months after transplantation. Two or three immunosuppressive agents typically are included in post‐transplant regimens with a total annual cost that can exceed $13 000. This represents a significant financial burden for families no matter if they have adequate health insurance coverage because of co‐payment obligations. Evidence suggests that some patients have reduced immunosuppression doses because of an inability to afford their medication, increasing the risk of graft failure. The purpose of this article was to review these and other issues pertaining to medical insurance coverage and transplantation, particularly for adolescent recipients as they transition to adulthood.
A relative resistance of T cells to dexamethasone in bipolar disorder
Authors: Knijff Esther M , Breunis M Nadine , Van Geest Marielle C , Kupka Ralph W , Ruwhof Cindy , De Wit Harm J , Nolen Willem A , Drexhage Hemmo A
Published: November 2006

Objective:  A relative resistance of immune cells to steroids has been established in patients with major depression (MD). In this study, we investigated the in vitro responsiveness of T cells to dexamethasone (DEX) of patients with bipolar disorder (BD).

Methods:  T cells of outpatients with DSM‐IV BD (n = 54) and of healthy control subjects (HC; n = 29) were isolated, cultured and stimulated with phytohemagglutinin (PHA) for 72 h. The suppressive effect of graded concentrations of DEX (5 × 10−9–10−5 M) on PHA‐induced CD25 (IL‐2R) expression was measured by fluorescence‐activated cell sorting (FACS) analysis. Data were correlated to the T‐cell activation status in the peripheral blood of the same patients and to their diagnosis, current mood state, ultradian cycling pattern and current use of medication, including lithium.

Results:  T cells of patients with BD were less sensitive to DEX‐induced suppressive effects as compared with T cells of HC. These data were particularly evident at 10−7 M DEX (mean % suppression ± SEM BD: 18.9% ± 3.5 versus HC: 35.8% ± 4.7, p = 0.001). We found no correlations of this relative in vitro DEX resistance of T cells neither with the previously mentioned clinical characteristics nor with the actual activation status of the T cells in the BD patients.

Conclusion:  A relative T‐cell resistance to steroids, as has been observed in MD previously, may be a trait phenomenon of BD, independent of mood state.
Co‐occurrence of bipolar and attention‐deficit hyperactivity disorders in children
Authors: Singh Manpreet K , DelBello Melissa P , Kowatch Robert A , Strakowski Stephen M
Published: November 2006

Objectives:  Pediatric bipolar disorder (BPD) and attention‐deficit hyperactivity disorder (ADHD) co‐occur more frequently than expected by chance. In this review, we examine 4 potential explanations for the high rate of this common co‐occurrence: (i) BPD symptom expression leads to overdiagnosis of ADHD in BPD youth; (ii) ADHD is a prodromal or early manifestation of pediatric‐onset BPD; (iii) ADHD and associated factors (e.g., psychostimulants) lead to the onset of pediatric BPD; and (iv) ADHD and BPD share an underlying biological etiology (i.e., a common familial or genetic risk or underlying neurophysiology).

Methods:  Peer‐reviewed publications of studies of children and adolescents with comorbid BPD and ADHD were reviewed.

Results:  There is a bidirectional overlap between BPD and ADHD in youth, with high rates of ADHD present in children with BPD (up to 85%), and elevated rates of BPD in children with ADHD (up to 22%). Phenomenologic, genetic, family, neuroimaging, and treatment studies revealed that BPD and ADHD have both common and distinct characteristics. While there are data to support all 4 explanations postulated in this paper, the literature most strongly suggests that ADHD symptoms represent a prodromal or early manifestation of pediatric‐onset BPD in certain at‐risk individuals. Bipolar disorder with comorbid ADHD may thus represent a developmentally specific phenotype of early‐onset BPD.

Conclusions:  The etiology of comorbid BPD and ADHD is likely multifactorial. Additional longitudinal and biological studies are warranted to clarify the relationships between BPD and ADHD since they may have important diagnostic and treatment implications.
Comorbidity of eating disorders with bipolar disorder and treatment implications
Authors: McElroy Susan L , Kotwal Renu , Keck Paul E
Published: November 2006

Objectives:  To review the scientific evidence examining the comorbidity among eating disorders and bipolar disorder (BD).

Methods:  We reviewed all published English‐language studies addressing the comorbidity of anorexia nervosa, bulimia, bulimia nervosa, and binge eating disorder in patients with BD and studies of comorbidity of BD in patients with eating disorders. In addition, we discuss the pharmacologic treatment implications from reviewed studies of agents used in BD and eating disorders.

Results:  Community and clinical population studies of the lifetime prevalence rates of eating disorders in patients with BD, and of BD in patients with eating disorders, particularly when subthreshold and spectrum manifestations of these disorders are included, indicate high rates of comorbidity among these illnesses.

Conclusions:  Pharmacologic treatment approaches to patients with BD and a co‐occurring eating disorder require examination of the possible adverse effects of the treatment of each syndrome on the other and attempts to manage both syndromes with agents that might be beneficial to both.
Inbreeding avoidance in spiders: evidence for rescue effect in fecundity of female spiders with outbreeding opportunity
Authors: Bilde T. , Maklakov A. A. , Schilling N.
Published: November 2006

Selection by inbreeding depression should favour mating biases that reduce the risk of fertilization by related mates. However, equivocal evidence for inbreeding avoidance questions the strength of inbreeding depression as a selective force in the evolution of mating biases. Lack of inbreeding avoidance can be because of low risk of inbreeding, variation in tolerance to inbreeding or high costs of outbreeding. We examined the relationship between inbreeding depression and inbreeding avoidance adaptations under two levels of inbreeding in the spider Oedothorax apicatus, asking whether preference for unrelated sperm via pre- and/or post-copulatory mechanisms could restore female fitness when inbreeding depression increases. Using inbred isofemale lines we provided female spiders with one or two male spiders of different relatedness in five combinations: one male sib; one male nonsib; two male sibs; two male nonsibs; one male sib and one male nonsib. We assessed the effect of mating treatment on fecundity and hatching success of eggs after one and three generations of inbreeding. Inbreeding depression in F1 was not sufficient to detect inbreeding avoidance. In F3, inbreeding depression caused a major decline in fecundity and hatching rates of eggs. This effect was mitigated by complete recovery in fecundity in the sib–nonsib treatment, whereas no rescue effect was detected in the hatching success of eggs. The rescue effect is best explained by post-mating discrimination against kin via differential allocation of resources. The natural history of O. apicatus suggests that the costs of outbreeding may be low which combined with high costs of inbreeding should select for avoidance mechanisms. Direct benefits of post-mating inbreeding avoidance and possibly low costs of female multiple mating can favour polyandry as an inbreeding avoidance mechanism.
Which patients are more likely to benefit from postoperative shed blood salvage after unilateral total knee replacement? An analysis of 581 consecutive procedures
Authors: Muñoz M. , Kühlmorgen B. , Ariza D. , Haro E. , Marroquí A. , Ramirez G.
Published: November 2006

Introduction  Requirements for allogeneic blood transfusion (ABT) after total knee replacement (TKR) are still high (30–50%), and salvage of unwashed filtered postoperative shed blood (USB) may represent an alternative to ABT. We evaluated that patients are more likely to benefit of USB reinfusion after TKR.

Patients and Methods  Data from 581 consecutive primary TKR, managed with (reinfusion group, n= 382) or without (control group, n= 199) reinfusion of USB, were retrospectively reviewed.

Results  Patients from reinfusion group received 119 ± 88 ml of red blood cells from USB, without clinically relevant incidents, and showed a lower ABT rate (30.6% vs. 8·4%, for control and reinfusion groups, respectively; P = 0·001) (transfusion trigger, haemoglobin [Hb] < 9 g/dl). Differences in ABT rate between groups were significant for all preoperative Hb levels, except for Hb ≤ 12 g/dl. A lower transfusion threshold (Hb < 8 g/dl) might have further decreased ABT rate (14·6% vs. 5·2%, respectively; P < 0·001), with differences being significant for preoperative Hb between 12 and 15 g/dl. There were no differences with respect to postoperative infection rate, but patients from reinfusion group had a shorter length of hospital stay (11 ± 4 vs. 13 ± 4 days, respectively; P= 0·001).

Conclusions  Return of USB after TKR seems to reduce the need for ABT, especially in patients with preoperative Hb between 12 and 15 g/dl. There is little benefit of USB reinfusion for patients with preoperative Hb > 15 g/dl, whereas patients with preoperative Hb < 12 g/dl would probably benefit from the combination of USB with some other blood‐saving method.
A Comparative Ontogenic Study of Urinary Bladder: Impact of the Epithelial Differentiation in Embryonic and Newborn Rats
Authors: Ersoy Y. , Ercan F. , ÇEtinel Ş.
Published: November 2006

The present study aimed to show the cellular and subcellular distribution of glycogen content during the differentiation of urothelial cells from simple cuboidal to stratified transitional epithelium. Bladder samples were taken from rat embryos on the 15th to 19th days and newborn at 21st day. During the development of the bladder, the formation of fusiform vesicles, asymmetric unit membrane (AUM) and microridges were examined with staining with haematoxylin–eosin and periodic acid Schiff for light microscope and periodic acid–thiocharbohydrazide–silver proteinate for transmission electron microscope. The topographical changes of luminal differentiation were examined with the scanning electron microscope. The urothelium was simple cuboidal from 15th till the 17th days of gestation. Glycogen content was present in the cytoplasm till the 18th day of gestation. At the early stage (16th day) of gestation, the apical surface contains microvilli that points the undifferentiated cells. The density of microvilli decreased and ropy microridges appeared at the 17th day of gestation. The small discoid vesicles lined with AUM developed at the apical cytoplasm of the surface cells at the 17th day of gestation. After this stage, both the density of microridges and large and elongated fusiform vesicles increased. The differentiation of the urothelium begins with the formation of the round and small vesicles, continues with the formation of the AUM and at the final stage there is a decrease in both glycogen content and the appearance of the microridges at the luminal surface of the urothelial cells.
Defining Cytochemical Markers for Different Cell Types in the Equine Retina
Authors: Deeg C. A. , Amann B. , Hauck S. M. , Kaspers B.
Published: November 2006

The major cell types in the mammalian retina are photoreceptors, amacrine, horizontal, bipolar, ganglion and Mueller glial cells. Most of the specific cell types are conserved, but cytochemical markers vary between species. The aim of our study was to characterize cytochemically distinctive markers for different cell types in the equine retina. We were able to define specific markers for equine Mueller glial cells and photoreceptor cells. Furthermore, we describe markers for large ganglion cells, horizontal and amacrine cells and a subpopulation of bipolar cells. Additionally, discrimination between the inner plexiform layer and nerve fibre layer can be achieved by expression of syntaxin and neurofilament 200 respectively.
Variability of Endotoxin Expression in Bt Transgenic Cotton
Authors: Dong H. Z. , Li W. J.
Published: November 2006

Transgenic cotton expressing Bt (Bacillus thuringiensis) toxins is currently cultivated on a large commercial scale in many countries, but observations have shown that it behaves variably in toxin efficacy against target insects under field conditions. Understanding of the temporal and spatial variation in efficacy and the resulting mechanisms is essential for cotton protection and production. In this review, we summarize current knowledge on variability in Bt cotton efficacy, in particular on the induced variability by environmental stresses. We also discuss the resulting mechanisms and the countermeasures for the inconsistence in efficacy in Bt cotton. It is indicated that insecticidal protein content in Bt cotton is variable with plant age, plant structure or under certain environmental stresses. Variability in Bt cotton efficacy against target insect pests is mainly attributed to the changes in Bt protein content, but physiological changes associated with the production of secondary compounds in plant tissues may also play an important role. Reduction of Bt protein content in late‐season cotton could be due to the overexpression of Bt gene at earlier stages, which leads to gene regulation at post‐transcription levels and consequently results in gene silencing at a later stage. Methylation of the promotor may be also involved in the declined expression of endotoxin proteins. As a part of total protein, the insecticidal protein in plant tissues changes its level through inhibited synthesis, degradation or translocation to developing plant parts, particularly under environmental stresses, thus being closely correlated to N metabolism. It can be concluded that developing new cotton varieties with more powerful resistance, applying certain plant growth regulators, enhancing intra‐plant defensive capability, and maintenance of general health of the transgenic crop are important in realizing the full transgenic potential in Bt cotton.