bluuebunny/crossref_metadata_2025 huggingface dataset:
DNA barcoding reveals extraordinary cryptic diversity in an amphipod genus: implications for desert spring conservation
Authors: WITT JONATHAN D. S. , THRELOFF DOUG L. , HEBERT PAUL D. N.
Published: July 2006

DNA barcoding has revealed unrecognized species in several animal groups. In this study we have employed DNA barcoding to examine Hyalella, a taxonomically difficult genus of amphipod crustaceans, from sites in the southern Great Basin of California and Nevada, USA. We assessed the extent of species diversity using a species screening threshold (SST) set at 10 times the average intrapopulation cytochrome c oxidase subunit I (COI) haplotype divergence. Despite the fact that this threshold approach is more conservative in delineating provisional species than the phylogenetic species concept, our analyses revealed extraordinary levels of cryptic diversity and endemism. The SST discriminated two provisional species within Hyalella sandra, and 33 provisional species within Hyalella azteca. COI nucleotide divergences among these provisional species ranged from 4.4% to 29.9%. These results have important implications for the conservation of life in desert springs — habitats that are threatened as a result of groundwater over‐exploitation.
Thresholds for health insurance in Rwanda: who should pay how much?
Authors: Schmidt Jean‐Olivier , Mayindo Jean K. , Kalk Andreas
Published: July 2006

Community‐based health insurance schemes were introduced in Rwanda in 1999 and now cover 27% of the population. Due to widespread poverty, it remains unclear to what degree poorer population strata can be anticipated to pay into the system. This study investigates the extent to which the Rwandan population can financially contribute to obtain health insurance. More specifically, researchers explored the relationship between resource mobilization for the health system and the ability to provide community‐based health insurance across socio‐economic strata. Data from six household surveys are analysed revealing a consistent pattern: the goals of maximizing health revenue and maximizing participation in community‐based health insurance are mutually exclusive. However, the upper three quartiles of the Rwandan population are able to contribute US$1 per capita per year. In order to extend coverage to the poorest quartile, a corresponding subsidy for the coming years has to be considered.
Predictors of treatment error for children with uncomplicated malaria seen as outpatients in Blantyre district, Malawi
Authors: Osterholt Dawn M. , Rowe Alexander K. , Hamel Mary J. , Flanders William D. , Mkandala Christopher , Marum Lawrence H. , Kaimila Nyokase
Published: July 2006

Background  Past studies have shown that health workers in developing countries often do not follow clinical guidelines, though few studies have explored with appropriate methods why errors occur. To develop interventions that improve health worker performance, factors affecting treatment practices must be better understood.

Methods  We analysed data from a health facility survey in Blantyre District, Malawi, in which health workers were observed treating ill children, and then children were independently re‐examined by ‘gold‐standard’ study clinicians. The analysis was limited to children with uncomplicated malaria (defined according to Malawi's guidelines as fever or anaemia without signs of severe illness), and a treatment error was defined as failure to treat with an effective antimalarial.

Results  Twenty‐eight health workers and 349 ill‐child consultations were evaluated; 247 (70.8%) children were treated with an effective antimalarial, and 102 (29.2%) were subject to treatment error. Logistic regression analysis revealed that in‐service malaria training was not associated with treatment quality (univariate odds ratio (OR) = 1.16, 95% confidence interval (CI): 0.46–2.93); whereas acute respiratory infections training was associated with making an error (adjusted OR (aOR) = 2.42, 95% CI: 1.23–4.76). High fever and chief complaint of fever were associated with fewer errors (aOR = 0.25, 95% CI: 0.10–0.60 and aOR = 0.25, 95% CI: 0.13–0.48, respectively). Errors were more likely to occur in consultations starting before 1 p.m. (aOR = 1.88, 95% CI: 1.07–3.31). Supervision was not associated with better treatment quality.

Conclusions  These results suggest that the disease‐specific training and supervision, performed before the survey, did not lead to long‐term improvements in health care quality. Furthermore, case management training for one specific disease may have worsened quality of care for another disease. These results support integration of guidelines for multiple conditions. Interventions should be evaluated for unintended negative effects on overall quality of care.
Maintenance of soil functioning following erosion of microbial diversity
Authors: Wertz Sophie , Degrange Valérie , Prosser James I. , Poly Franck , Commeaux Claire , Freitag Thomas , Guillaumaud Nadine , Roux Xavier Le
Published: July 2006

The paradigm that soil microbial communities, being very diverse, have high functional redundancy levels, so that erosion of microbial diversity is less important for ecosystem functioning than erosion of plant or animal diversity, is often taken for granted. However, this has only been demonstrated for decomposition/respiration functions, performed by a large proportion of the total microbial community, but not for specialized microbial groups. Here, we determined the impact of a decrease in soil microbial diversity on soil ecosystem processes using a removal approach, in which less abundant species were removed preferentially. This was achieved by inoculation of sterile soil microcosms with serial dilutions of a suspension obtained from the same non‐sterile soil and subsequent incubation, to enable recovery of community size. The sensitivity to diversity erosion was evaluated for three microbial functional groups with known contrasting taxonomic diversities (ammonia oxidizers < denitrifiers < heterotrophs). Diversity erosion within each functional group was characterized using molecular fingerprinting techniques: ribosomal intergenic spacer analysis (RISA) for the eubacterial community, denaturing gradient gel electrophoresis (DGGE) analysis ofnirKgenes for denitrifiers, and DGGE analysis of 16S rRNA genes for betaproteobacterial ammonia oxidizers. In addition, we simulated the impact of the removal approach by dilution on the number of soil bacterial species remaining in the inoculum using values of abundance distribution of bacterial species reported in the literature. The reduction of the diversity of the functional groups observed from genetic fingerprints did not impair the associated functioning of these groups, i.e. carbon mineralization, denitrification and nitrification. This was remarkable, because the amplitude of diversity erosion generated by the dilution approach was huge (level of bacterial species loss was estimated to be around 99.99% for the highest dilution). Our results demonstrate that the vast diversity of the soil microbiota makes soil ecosystem functioning largely insensitive to biodiversity erosion even for functions performed by specialized groups.
Long‐term exposure to elevated zinc concentrations induced structural changes and zinc tolerance of the nitrifying community in soil
Authors: Mertens Jelle , Springael Dirk , De Troyer Inne , Cheyns Karlien , Wattiau Pierre , Smolders Erik
Published: July 2006

A series of long‐term Zn‐contaminated soils was sampled around a galvanized pylon. The potential nitrification rate (PNR) was unaffected by the soil total Zn concentrations up to 25 mmol Zn kg−1 whereas spiking the uncontaminated control soil with ZnCl2 to identical total concentrations completely eliminated nitrification. The larger sensitivity of the PNR to spiked ZnCl2 than to the Zn added in the field was equally found when relating the PNR to the Zn concentrations in the pore water of these soils, suggesting differences in Zn tolerance of the nitrifying communities. Zinc tolerance in the long‐term Zn‐contaminated soil was demonstrated by showing that (i) the nitrifying community of long‐term Zn‐contaminated soil samples was less sensitive to Zn than that of the uncontaminated control soil when both communities were inoculated in sterile ZnCl2‐contaminated soil samples, and, that (ii) addition of ZnCl2 to the long‐term Zn‐contaminated soil samples affected nitrification less than equal additions of ZnCl2 to uncontaminated control samples. Denaturing gradient gel electrophoresis fingerprinting of polymerase chain reaction amplified 16SrRNA gene fragments of ammonia‐oxidizing bacteria showed that the community structure in uncontaminated and long‐term contaminated soil samples was different and could be related to soil Zn concentrations.
Insect diversity in Cape fynbos and neighbouring South African vegetation
Authors: Procheş Şerban , Cowling Richard M.
Published: July 2006

Aim  It has often been suggested that South Africa's Cape fynbos shrublands, although extremely rich in plant species, are poor in insects, thus representing a notable exception from the broad plant–insect diversity relationship. The aims of this study were to compare the diversity patterns of plant‐inhabiting insects in fynbos and the vegetation of three neighbouring biomes (grassland, subtropical thicket, and Nama‐karoo), and to test for a general relationship between plant diversity and insect diversity across these biomes.

Location  South‐western to south‐eastern South Africa.

Methods  We conducted seasonal plant surveys and sweep insect sampling in 10 × 10 m plots in the Baviaanskloof Conservation Area (Eastern Cape), where all four biomes occur. We also conducted once‐only collections in the core area of each biome.

Results  Fynbos plots had insect diversity values similar to those of grassland and subtropical thicket (a dense, evergreen and spinescent shrubland with a high abundance of succulents and climbers), and significantly higher than Nama‐karoo (an open, semiarid shrubland). A remarkably strong positive relationship was found between plant and insect species richness.

Main conclusions  Previous generalizations were based on a few insect groups (e.g. butterflies, under‐represented in fynbos), but ignored published results on other groups (e.g. galling insects, which are in fact over‐represented in this vegetation). We show that, overall, insect diversity in fynbos is comparable to that of neighbouring biomes. Fynbos vegetation does not represent a significant exception from the broad positive relationship between plant diversity and insect diversity.
Modelled photosynthesis predicts woody plant richness at three geographic scales across the north‐western United States
Authors: Swenson Jennifer J. , Waring Richard H.
Published: July 2006

Aim We analyse regional patterns of woody plant species richness collected from field data in relation to modelled gross photosynthesis, Pg, compare the performance of Pgin relation to other productivity surrogates, and examine the effect of increasing scale on the productivity–richness relationship.

Location The forested areas in the north‐western states of Oregon, Washington, Idaho, and Montana, USA.

Methods Data on shrub and tree species richness were assembled from federal vegetation surveys and compared with modelled growing season gross photosynthesis, Pg(the sum of above‐ and below‐ground production plus autotrophic respiration) and two measures of spatial heterogeneity. We analysed the productivity–richness relationship at different scales by changing the focus size through spatial aggregation of field plots using 100 and 1000 km2windows covering the study area. Regression residuals were plotted spatially. Using the best available tree data set (Continuous Vegetation Survey: CVS), we compared different productivity indices, such as actual evapotranspiration and average temperature, in their ability to predict patterns of tree species richness.

Results The highest species richness (species/unit area) occurred at intermediate levels of productivity. After accounting for variable sampling intensity, the richness–productivity relationship improved as more field plots were aggregated. At coarser levels of aggregation, modelled productivity accounted for 57–71% of the variation in richness patterns for shrubs and trees (CVS data set). Measures of spatial heterogeneity accounted for more variation in richness patterns aggregated by 100 km2windows than aggregation by 1000 km2windows. Pgwas a better predictor of tree richness in Oregon and Washington (CVS data set) than any surrogate productivity index.

Main conclusions Pgwas observed to be a strong unimodal predictor of both tree (CVS) and shrub (FIA) richness when field data were aggregated. For the tree data set examined, seasonally integrated estimates of photosynthesis (Pg) predicted tree richness patterns better than climatic indices did.
Beyond Rapoport's rule: evaluating range size patterns of New World birds in a two‐dimensional framework
Authors: Hawkins Bradford A. , Felizola Diniz‐Filho José Alexandre
Published: July 2006

Aim  To evaluate Rapoport's rule for New World birds in two‐dimensional geographical space. We specifically test for a topography × climate interaction that predicts little difference in range sizes between lowlands and mountains in cold climates, whereas in the tropics, montane species have narrow ranges and lowland species have broad ranges.

Location  The western hemisphere.

Methods  We used digitized range maps of breeding birds to generate mean range sizes in grids of 27.5 × 27.5 km and 110 × 110 km across North and South America. We examined the geographical pattern with respect to range in elevation, mean temperature in the coldest month, their interaction, biome size and continental width, using model II analysis of variance, multiple regression and simple correlation.

Results  In northern latitudes species have broad ranges in both mountainous and flat areas. However, range sizes in the mountains and lowlands diverge southwards, with the most extreme differences in the tropics. Further, there are minimal differences in range sizes across latitudes in lowlands. The smallest mean ranges occur in the tropical Andes. Mean range sizes in north‐central Canada, Central America and Argentina/Chile are also small, reflecting the narrowing of the continents in these areas. The best regression model explained 51% of the variation in mean range size.

Main conclusions  The two‐dimensional range size pattern indicates that neither winter temperature nor annual variability in temperature strongly influences the distribution of range sizes directly; rather, climate influences bird range sizes indirectly via effects on habitat size. Also, macroclimate interacts with topographic relief across latitudes, generating sharp mesoscale habitat gradients in tropical mountains but not in high latitude mountains or in lowlands at any latitude. Birds respond to these habitat gradients, resulting in ‘latitudinal’ range size gradients in topographically complex landscapes but not in simple landscapes.
How much may I eat? Calorie estimates based upon energy expenditure prediction equations
Authors: Heymsfield S. B. , Harp J. B. , Rowell P. N. , Nguyen A. M. , Pietrobelli A.
Published: July 2006

How much may I eat? Most healthcare workers, when asked this question, have insufficient knowledge to educate their patients on a healthy energy intake level. In this review we examine the available methods for estimating adult energy requirements with a focus on the newly developed National Academy of Sciences/Institute of Medicine (NAS/IOM) doubly‐labelled water total energy expenditure (TEE) prediction equations. An overview is first provided of the traditional factorial method of estimating energy requirements. We then extend this overview by exploring the development of the NAS/IOM TEE prediction models and their role in estimating energy requirments as a function of sex, age, weight, height and physical activity level. The NAS/IOM prediction models were developed for evaluating group energy requirements, although the formulas can be applied in individual ‘example’ patients for educational purposes. Potential limitations and interpretation issues of both the factorial and NAS/IOM methods are examined. This information should provide healthcare professionals with the tools and understanding to appropriately answer the question, ‘How much may I eat?’
Fulminant toxoplasmosis causing fatal pneumonitis and myocarditis
Authors: Eza DE , Lucas SB
Published: July 2006

The obligate intracellular protozoa Toxoplasma gondii is a serious cause of morbidity and mortality in patients with AIDS. Toxoplasmosis most frequently manifests as life‐threatening encephalitis, although extracerebral sites may be involved with or without toxoplasmic encephalitis. Consequently, toxoplasmosis can present in an unusual manner, and may not be included in the differential diagnosis in the absence of encephalitic symptoms. There are few reports of fulminant toxoplasmic myocarditis resulting in death. Toxoplasmic pneumonitis is responsible for less than 1% of HIV‐related pulmonary complications, and can occasionally cause fatal septic shock. Two such clinicopathological presentations of toxoplasmosis are reported here. One patient presented with cardiorespiratory signs and symptoms, whilst the second patient presented with pneumonitis and renal failure. Neither patient was initially known to be HIV‐infected, nor did they have clinical symptoms indicating toxoplasmic encephalitis. Toxoplasmosis was only diagnosed on autopsy and had resulted in death by causing a fulminant myocarditis and a pneumonitis. As overwhelming toxoplasmosis infection may prove rapidly fatal, these two case reports serve as a clinical reminder to consider toxoplasmosis in the differential diagnosis of HIV‐infected patients who present with severe cardiorespiratory signs and symptoms. Furthermore, the cases emphasize the potential importance of early tissue biopsy in patients presenting with immunosuppression‐associated organ failure, and show the importance of requesting a postmortem examination if the cause of death cannot be ascertained in vivo.
Community‐onset methicillin‐resistant Staphylococcus aureus in an urban HIV clinic
Authors: Skiest D , Brown K , Hester J , Moore T , Crosby C , Mussa HR , Hoffman‐Roberts H , Cooper T
Published: July 2006

Objectives

To determine the proportion of skin/soft tissue infections (SSTIs) and to determine risks for MRSA infection caused by methicillin‐resistant Staphylococcus aureus (MRSA) in HIV‐infected out‐patients.

Methods

We conducted a prospective study of SSTIs in HIV‐infected out‐patients. A questionnaire was used to record MRSA risk factors and treatment. In vitro testing for antibiotic susceptibility, inducible clindamycin resistance, panton‐valentine leucocidin (PVL) toxin, and the staphylococcal chromosomal cassette mec (SCCmec) type was performed using standardized methods. Treatment outcomes included resolution of primary site of infection, nonresolution of infection and reinfection and were confirmed at clinic visit and/or telephone follow‐up.

Results

Forty‐one of 44 patients had an SSTI caused by MRSA. African‐Americans comprised 21 of 41 MRSA patients. The median CD4 count of MRSA patients was 411 cells/μL. Four patients required hospitalization and three patients had secondary bacteraemia. Twenty‐one of 41 MRSA patients had healthcare‐associated (HCA) MRSA risk factors including a history of prior MRSA infection (n=9) and hospitalization within 6 months (n=11). Other prevalent MRSA risk factors included receipt of systemic antibiotics within 6 months (n=21) and previous incarceration (n=19). Twenty‐two patients had a significant non‐HIV‐related comorbid illness. The majority of isolates were susceptible to trimethoprim‐sulfamethoxazole, tetracycline, and clindamycin. Inducible clindamycin resistance was detected in 0 of 16 erythromycin‐resistant, clindamycin‐susceptible MRSA isolates. Twenty‐one of 24 isolates tested positive for SCCmec type IV. Twenty‐four of 24 isolates tested positive for the PVL gene. Antibiotic treatment was discordant (bacteria nonsusceptible to antibiotic used) in eight MRSA patients. The primary SSTI resolved in 37 of 40 MRSA patients. Recurrence of infection at a site other than the primary site was relatively common (11 patients).

Conclusions

We found a high rate of MRSA causing SSTI in community‐dwelling patients. The majority of isolates were positive for PVL and SCCmec IV, which is typical of community‐associated MRSA isolates causing SSTIs in the general population. Inducible clindamycin resistance was not detected. Most patients had MRSA risk factors. The initial site of infection resolved in most cases but subsequent MRSA infection was relatively common.
Abnormal glucose metabolism among older men with or at risk of HIV infection
Authors: Howard AA , Floris‐Moore M , Lo Y , Arnsten JH , Fleischer N , Klein RS
Published: July 2006

Objectives

To determine factors associated with diabetes, insulin resistance, and abnormal glucose tolerance in older men with or at risk of HIV infection.

Methods

Diabetes was assessed by self‐report in 643 men ≥49 years old with or at risk of HIV infection. In a subset of 216 men without previously diagnosed diabetes [including 90 HIV‐uninfected men, 28 HIV‐infected, antiretroviral‐naive men, 28 HIV‐infected men taking non‐protease inhibitor (PI)‐containing highly active antiretroviral therapy (HAART), and 70 HIV‐infected men taking PI‐containing HAART], an oral glucose tolerance test with insulin levels was performed. HIV serology, CD4 cell count, weight, height and waist circumference were measured. Antiretroviral use, drug use, family history of diabetes, physical activity and sociodemographic data were obtained using standardized interviews.

Results

Of 643 participants, 116 (18%) had previously diagnosed diabetes. With the oral glucose tolerance test, 15 of 216 men (7%) were found to have undiagnosed diabetes and 40 (18%) impaired glucose tolerance. Factors independently associated with previously diagnosed diabetes included use of non‐PI‐containing HAART, methadone treatment, positive CAGE test for alcoholism, obesity and family history of diabetes. Factors independently associated with greater insulin resistance included waist circumference and heroin use. Factors independently associated with abnormal glucose tolerance (impaired glucose tolerance or diabetes) included age ≥55 years and Hispanic ethnicity.

Conclusions

HIV‐infected men with diabetes risk factors should undergo screening for diabetes regardless of HAART use. Interventions targeting modifiable risk factors, including overweight and physical inactivity, are warranted. The potential impact of opiate and alcohol abuse on glucose metabolism should be recognized in clinical care, and addressed in future research studies of HIV‐infected persons.
A randomized, open‐label study to compare the effects of two different doses of recombinant human growth hormone on fat reduction and fasting metabolic parameters in HIV‐1‐infected patients with lipodystrophy
Authors: Bickel M , Zangos S , Jacobi V , Lutz T , Knecht G , Goebel F , Staszewski S , Klauke S
Published: July 2006

Background

Several studies have shown beneficial effects of recombinant human growth hormone (r‐hGH) in reducing visceral adipose tissue (VAT) in HIV‐1‐infected patients with lipodystrophy.

Methods

Patients were randomized to r‐hGH 4 mg daily (group A) or three times per week (group B) over 12 weeks, followed by a 2 mg daily maintenance dose for 12 weeks. Magnetic resonance imaging (MRI) scans were performed to assess body composition.

Results

A total of 26 subjects were included in the study. VAT was reduced overall by 35.1 cm2 (29.5%) at week 12 and by 49 cm2 (39.9%) at week 24, respectively, compared with baseline (P<0.001 for both comparisons). By week 12, VAT was reduced by 27 and 29% (A vs B; P=0.47) while facial fat was reduced by 3.3 and 2.6 cm2 in groups A and B, respectively (P=0.96). Over 24 weeks, VAT was reduced by 42 and 38% (P=0.35) and facial fat by 3.2 and 2.4 cm2 in groups A and B, respectively (P=0.91), compared with baseline. There was a greater increase in high‐density lipoprotein (HDL) in group A than in group B (4.9 vs 2.4 mg/dL in week 12 and 7.1 vs −0.4 mg/dL in week 24; P=0.03). Fasting insulin levels increased, whereas glucose and insulin measured in oral glucose tolerance tests remained unchanged. Drug‐related side effects were transient and reversible, but more common in group A (67%) than in group B (29%).

Conclusions

This study confirms reports that r‐hGH effectively reduces VAT, with a relatively small reduction of facial and limb fat.
Prevalence of risk factors for cardiovascular disease in HIV‐infected patients over time: the Swiss HIV Cohort Study
Authors: Glass TR , Ungsedhapand C , Wolbers M , Weber R , Vernazza PL , Rickenbach M , Furrer H , Bernasconi E , Cavassini M , Hirschel B , Battegay M , Bucher HC ,   the Swiss HIV Cohort Study
Published: July 2006

Objective

Metabolic changes caused by antiretroviral therapy (ART) may increase the risk of coronary heart disease (CHD). We evaluated changes in the prevalence of cardiovascular risk factors (CVRFs) and 10‐year risk of CHD in a large cohort of HIV‐infected individuals.

Methods

All individuals from the Swiss HIV Cohort Study (SHCS) who completed at least one CVRF questionnaire and for whom laboratory data were available for the period February 2000 to February 2006 were included in the analysis. The presence of a risk factor was determined using cut‐offs based on the guidelines of the National Cholesterol Education Program (NCEP ATP III), the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure (JNC7), the American Diabetes Association, and the Swiss Society for Cardiology.

Results

Overall, 8033 individuals completed at least one CVRF questionnaire. The most common CVRFs in the first completed questionnaire were smoking (57.0%), low high‐density lipoprotein (HDL) cholesterol (37.2%), high triglycerides (35.7%), and high blood pressure (26.1%). In total, 2.7 and 13.8% of patients were categorized as being at high (>20%) and moderate (10–20%) 10‐year risk for CHD, respectively. Over 6 years the percentage of smokers decreased from 61.4 to 47.6% and the percentage of individuals with total cholesterol >6.2 mmol/L decreased from 21.1 to 12.3%. The prevalence of CVRFs and CHD risk was higher in patients currently on ART than in either pretreated or ART‐naive patients.

Conclusion

During the 6‐year observation period, the prevalence of CVRFs remains high in the SHCS. Time trends indicate a decrease in the percentage of smokers and individuals with high cholesterol.
Return Dynamics in Bosnia1and Croatia: A Comparative Analysis
Authors: Harvey Joanna
Published: July 2006

More than ten years after the end of the conflicts in Bosnia and Croatia, this paper examines the process of return of the displaced to their homes, offering a comparison of factors affecting the process in the two countries. The first section sketches the nature and modality of obstruction to minority return in places of origin, describing some of the ways in which politicized obstruction has interacted with other conditions in return locations. The second section looks at the impact on the return process of conditions in places of refuge, examining how particular circumstances of their displacement have differently affected questions of mobilization and representation among displaced communities. In particular, some observations are made about the relationships between the displaced communities and the authorities in the various places of refuge, and about the effect that these relationships have had on the approach taken to the question of return by the different communities. In the final section a comparison is made of the nature of international intervention to support minority returns in the two countries, arguing that considerably more resources, attention, and diplomatic pressure were focused on the question of minority return to Bosnia than to Croatia. Some possible explanations for this include the burden on third countries of large numbers of Bosnian refugees, the perceived peace‐building imperative behind minority returns in Bosnia, and the attempt to redress the highly visible failures of the international community in preventing ethnic cleansing there. These factors are absent in the Croatian context, and it is argued that the corresponding lack of attention to minority return there demonstrates an inconsistency behind the moral claim made by international actors in upholding the right to return. The paper concludes by commenting on the effect of the combination of these factors on individual displaced persons and refugees, and on the parallels that can be drawn with other situations of forced migration, specifically Kosovo (Republic of Serbia).3Current opportunities to redress some of the inconsistencies in approach and outstanding obstacles to return are highlighted.
Changes in cerebral membrane lipid composition and fluidity during thioacetamide‐induced hepatic encephalopathy
Authors: Swapna I. , SathyaSaiKumar K. V. , Murthy Ch. R. K. , Dutta‐Gupta A. , Senthilkumaran B.
Published: July 2006

Lipids are an essential structural and functional component of cellular membranes. Changes in membrane lipid composition are known to affect the activities of many membrane‐associated enzymes, endocytosis, exocytosis, membrane fusion and neurotransmitter uptake, and have been implicated in the pathophysiology of many neurodegenerative disorders. In the present study, we investigated changes in the lipid composition of membranes isolated from the cerebral cortex of rats treated with thioacetamide (TAA), a hepatotoxin that induces fulminant hepatic failure (FHF) and thereon hepatic encephalopathy (HE). HE refers to acute neuropsychiatric changes accompanying FHF. The estimation of membrane phospholipids, cholesterol and fatty acid content in cerebral cortex membranes from TAA‐treated rats revealed a decrease in cholesterol, phosphatidylserine, sphingomyelin, a monounsaturated fatty acid, namely oleic acid, and the polyunsaturated fatty acids γ‐linolenic acid, decosa hexanoic acid and arachidonic acid compared with controls. Assessment of membrane fluidity with pyrene, 1,6‐diphenyl‐1,3,5‐hexatriene and 1‐[4‐(trimethylammonio)phenyl]‐6‐phenyl‐1,3,5‐hexatriene revealed a decrease in the annular membrane fluidity, whereas the global fluidity was unaffected. The level of the thiobarbituric acid reactive species marker for lipid peroxidation also increased in membranes from TAA‐treated rats, thereby indicating the prevalence of oxidative stress. Results from the present study demonstrate gross alterations in cerebral cortical membrane lipid composition and fluidity during TAA‐induced HE, and their possible implications in the pathogenesis of this condition are also discussed.
Interleukin‐1β induces the expression of aquaporin‐4 through a nuclear factor‐κB pathway in rat astrocytes
Authors: Ito Hiroaki , Yamamoto Naoki , Arima Hajime , Hirate Hiroyuki , Morishima Tetsuro , Umenishi Fuminori , Tada Toyohiro , Asai Kiyofumi , Katsuya Hirotada , Sobue Kazuya
Published: July 2006

Interleukin (IL)‐1β is known to play a role in the formation of brain edema after various types of injury. Aquaporin (AQP)4 is also reported to be involved in the progression of brain edema. We tested the hypothesis that AQP4 is induced in response to IL‐1β. We found that expression of AQP4 mRNA and protein was significantly up‐regulated by IL‐1β in cultured rat astrocytes, and that intracerebroventricular administration of IL‐1β increased the expression of AQP4 protein in rat brain. The effects of IL‐1β on induction of AQP4 were concentration and time dependent. The effects of IL‐1β on AQP4 were mediated through IL‐1β receptors because they were abolished by co‐incubation with IL‐1 receptor antagonist. It appeared that IL‐1β increased the level of AQP4 mRNA without involvement of de novo protein synthesis because cycloheximide, a protein synthesis inhibitor, did not inhibit the effects of IL‐1β. Inhibition of the nuclear factor‐κB (NF‐κB) pathway blocked the induction of AQP4 by IL‐1β in a concentration‐dependent manner. These findings show that IL‐1β induces expression of AQP4 through a NF‐κB pathway without involvement of de novo protein synthesis in rat astrocytes.
Reduced expression of neuropeptide genes in a genome‐wide screen of a secretion‐deficient mouse
Authors: Bouwman J. , Spijker S. , Schut D. , Wächtler B. , Ylstra B. , Smit A. B. , Verhage M.
Published: July 2006

Activity‐dependent changes in synapses rely on functional changes in resident proteins and on gene expression. We addressed the relationship between synapse activity and the expression of synaptic genes by comparing RNA levels in the neocortex of normal mice versus secretion‐deficient and therefore synaptically silent munc18‐1 (mammalian homologue of Caenorhabditis elegans uncoordinated locomotion‐18) null mutants, using microarray expression analysis, real‐time quantitative PCR and northern blotting. We hypothesized that genes under the control of synaptic activity would be differentially expressed between mutants and controls. We found that few synaptic genes were differentially expressed. However, most neuropeptide genes with detectable expression on the microarray were differentially expressed, being expressed 3–20‐fold higher in control cortex. Several other secreted proteins were also differentially expressed, but genes encoding their receptors and many other synaptic components were not. Differential expression was confirmed by real‐time quantitative PCR analysis. In situ hybridization indicated that the difference in neuropeptide expression was uniform and not due to the loss of specific cells in the mutant. In primary sensory neurons, which do not depend on synaptic activity for their input, the differential expression of neuropeptides was not observed. These data argue against a general relationship between the activity of synapses and the expression of their resident proteins, but suggest a link between secretion and the expression of genes encoding the secreted products.
JAK2 and STAT3 activation contributes to neuronal damage following transient focal cerebral ischemia
Authors: Satriotomo Irawan , Bowen Kellie K. , Vemuganti Raghu
Published: July 2006

Increased levels of interleukin‐6 (IL‐6) play a role in post‐ischemic cerebral inflammation. IL‐6 binding to its receptors induces phosphorylation of the receptor associated janus kinases (JAKs), and the down‐stream signal transducer and activator of transcription (STAT) family of transcription factors, which amplify the IL‐6 signal transduction. We evaluated the functional significance of JAK2 and STAT3 activation in focal ischemia‐induced neuronal damage. Transient middle cerebral artery occlusion in adult rats led to increased JAK2 and STAT3 phosphorylation in the ipsilateral cortex and striatum after 6–72 h of reperfusion. Fluorescent immunohistochemistry with cell specific markers (NeuN for neurons, glial fibrillary acidic protein for reactive astrocytes and ED1/OX42 for activated macrophages/microglia) showed that both pJAK2 and pSTAT3 staining is predominantly localized in the macrophages/microglia in the post‐ischemic brain. Intracerebroventricular infusion of rats with AG490 (a JAK2 phosphorylation inhibitor) prevented the post‐ischemic JAK2 and STAT3 phosphorylation and significantly decreased the infarct volume, number of apoptotic cells and neurological deficits, compared to vehicle control. Furthermore, intracerebral injection of siRNA specific for STAT3 led to curtailed STAT3 mRNA expression and phosphorylation, decreased infarct volume, fewer apoptotic cells and improved neurological function following transient middle cerebral artery occlusion. These studies show that JAK2‐STAT3 activation plays a role in post‐ischemic brain damage.
Gain of function mutants reveal sites important for the interaction of the atypical inhibitors benztropine and bupropion with monoamine transporters
Authors: Mortensen Ole V. , Amara Susan G.
Published: July 2006

Two atypical inhibitors of the dopamine transporter, benztropine, used in the treatment of Parkinson's disease, and bupropion, used as an antidepressant, show very different psychostimulant effects when compared with another inhibitor, cocaine. Taking advantage of the differential sensitivity of the dopamine and the norepinephrine transporters (DAT and NET) to benztropine and bupropion, we have used site‐directed mutagenesis to produce gain‐of‐function mutants in NET which demonstrate that Ala279 in thetrans‐membrane domain 5 (TM5) and Ser359 in the TM7 of DAT are responsible for the higher sensitivity of DAT to both bupropion and benztropine. Substitution of these two DAT residues into the NET background does not alter the potency of NET‐selective inhibitors, such as desipramine. The results from experiments examining the ability of DAT‐selective inhibitors to displace [3H]nisoxetine binding in NET gain‐of‐function mutants suggest that Ser359 contributes to the initial binding of the inhibitor, and that Ala279 may influence subsequent steps involved in the blockade of translocation. Thus, these studies begin to identify residues that are important for the unique molecular interactions of benztropine and bupropion with the DAT, and that ultimately may contribute to the distinct behavioral actions of these drugs.
Development of microsatellite markers for the red‐listed wood‐decay fungus Phlebia centrifuga
Authors: FRANZÉN INA , SLIPPERS BERNARD , VASILIAUSKAS RIMVYDAS , STENLID JAN
Published: July 2006

Seven polymorphic microsatellite markers were developed for the wood‐decay basidiomycete Phlebia centrifuga. The primers were identified using two techniques, based on intersimple sequence repeats (ISSR) and amplified fragment length polymorphism (AFLP), respectively. The markers were screened on 27 isolates from Europe and North America. Two markers varied only on a worldwide scale, but not within Europe. The other five showed variation on both scales. These markers will now be used to characterize populations of P. centrifuga, which is red‐listed as near‐threatened in its natural habitat due to human disturbance.
EST‐derived polymorphic microsatellites from cultivated strawberry (Fragaria×ananassa) are useful for diversity studies and varietal identification among Fragaria species
Authors: GIL‐ARIZA D. J. , AMAYA I. , BOTELLA M. A. , BLANCO J. MUÑOZ , CABALLERO J. L. , LÓPEZ‐ARANDA J. M. , VALPUESTA V. , SÁNCHEZ‐SEVILLA J. F.
Published: July 2006

Microsatellite or simple sequence repeat markers derived from expressed sequence tags (ESTs) provide genetic markers within potentially functional genes, which could be very useful for breeding programs. To date, the development of microsatellite markers in the genus Fragaria has focused mainly on Fragaria vesca. However, most of the interests of breeding programs relate to specific characteristics of cultivated strawberry. Here, we describe a set of 10 EST‐derived microsatellites from Fragaria × ananassa. These markers showed high levels of polymorphism within strawberry cultivars and among different Fragaria species, indicating their potential for genetic studies not only on strawberry but also in other species within the genus.
Microsatellite loci transferability from Theobroma cacao to Theobroma grandiflorum
Authors: ALVES RAFAEL M. , SEBBENN ALEXANDRE M. , ARTERO ANGELA S. , FIGUEIRA ANTONIO
Published: July 2006

Theobroma grandiflorum (cupuassu) is an important fruit tree native to the Brazilian Amazon. Forty‐eight microsatellite loci developed for the congener Theobroma cacao were tested in cupuassu, and 29 (60.4%) produced robust alleles. The analyses of 216 cupuassu accessions using the 21 polymorphic microsatellite loci revealed a total of 113 alleles. The number of alleles per polymorphic locus ranged from two to 11, with an average of 5.38 alleles per locus. The average observed heterozygosity was 0.343, while the mean expected heterozygosity was 0.614. The successful transferability of T. cacao microsatellite primers to cupuassu was consistent with currently accepted phylogeny.
Regulation of inflammation by PPARs: a future approach to treat lung inflammatory diseases?
Authors: Becker Julien , Delayre‐Orthez Carine , Frossard Nelly , Pons Françoise
Published: July 2006

Lung inflammatory diseases, such as acute lung injury (ALI), asthma, chronic obstructive pulmonary disease (COPD) and lung fibrosis, represent a major health problem worldwide. Although glucocorticoids are the most potent anti‐inflammatory drug in asthma, they exhibit major side effects and have poor activity in lung inflammatory disorders such as ALI or COPD. Therefore, there is growing need for the development of alternative or new therapies to treat inflammation in the lung. Peroxisome proliferator‐activated receptors (PPARs), including the three isotypes PPARα, PPARβ (or PPARδ) and PPARγ, are transcription factors belonging to the nuclear hormone receptor superfamily. PPARs, and in particular PPARα and PPARγ, are well known for their critical role in the regulation of energy homeostasis by controlling expression of a variety of genes involved in lipid and carbohydrate metabolism. Synthetic ligands of the two receptor isotypes, the fibrates and the thiazolidinediones, are clinically used to treat dyslipidaemia and type 2 diabetes, respectively. Recently however, PPARα and PPARγ have been shown to exert a potent anti‐inflammatory activity, mainly through their ability to downregulate pro‐inflammatory gene expression and inflammatory cell functions. The present article reviews the current knowledge of the role of PPARα and PPARγ in controlling inflammation, and presents different findings suggesting that PPARα and PPARγ activators may be helpful in the treatment of lung inflammatory diseases.
Patterns in grouse and Woodcock Scolopax rusticola hunting yields from central Norway 1901–24 do not support the alternative prey hypothesis for grouse cycles
Authors: SELÅS VIDAR
Published: July 2006

According to the alternative prey hypothesis, autumn populations of ground‐nesting game birds fluctuate in synchrony with vole numbers because generalist predators that mainly eat voles switch to alternative prey, such as eggs and chicks, when vole numbers decline. In hunting statistics from Nord‐Trøndelag, central Norway, 1901–24, annual fluctuations in the number of Willow Grouse Lagopus lagopus and Western Capercaillie Tetrao urogallus, but not of Woodcock Scolopax rusticola, were positively related to vole numbers in the current year. Both Woodcock and grouse indices were related to hunting indices of Goshawk Accipiter gentilis and to weather variables assumed to influence the birds’ survival or reproduction, suggesting that the indices actually reflected local population levels. Synchronous vole and grouse fluctuations are consistent with the alternative prey hypothesis (although predator densities were low in the early 1900s), but the asynchronous Woodcock fluctuations refute the hypothesis. Rather, because the Woodcock does not feed on plants utilized by voles and grouse, I suggest that food quality is the ultimate factor for the synchrony in vole and grouse numbers in Norway.
Origins and characteristics of Nearctic landbirds in Britain and Ireland in autumn: a statistical analysis
Authors: MCLAREN IAN A. , LEES ALEXANDER C. , FIELD CHRIS , COLLINS KRISTA J.
Published: July 2006

We used data from eastern North America in regressions to explain autumn frequencies of Nearctic landbird species in Britain and Ireland (UK‐IR). The data were: day‐counts of 16 August–15 November from Nova Scotia (NS) on Sable Island 1963–2000 and Seal Island (1963–2002), combined in half‐monthly intervals to account for seasonality; published seasonal totals (10‐ to 11‐day intervals, 20 August–10 November 1955–80) of birds killed at a Florida (FL) TV tower; and published counts following a ‘Fallout’, 11 October 1998, of unseasonal species and southern vagrants in NS, believed to have originated as migrants in the southeast USA that followed a cold front offshore into strong southwest flow beyond. We also used the following species variables: body mass and wing length for size; sd of mass as a proxy for lipid capacity; a five‐level index of migratory span (1 for within North America to 5 for almost totally to South America); latitude of easternmost breeding, and distance to nearest normal range to indicate status in NS; a two‐level index for day vs. night migrants; an index, where pertinent, of significant population change (0 and 2 for a decrease and increase, respectively, 1 for no change). We also used classification and regression trees to cluster the potential transatlantic vagrants into homogeneous groups based on the explanatory variables. Standard generalized linear model regressions using counts from NS islands and FL produced highly positively skewed residuals (many species too common in UK‐IR), but robust regressions eliminated statistical problems, and strengthened effects of non‐count variables. Results using Fallout records, representing a subset of longer‐distance night migrants, were statistically acceptable. The Fallout list, when supplied with counts from the same species from the NS islands and FL, produced highly significant (R2 = 0.79–0.93) and statistically acceptable regressions that were not improved by robust versions. Overall, the results indicate that October counts, especially of generally larger, longer‐distance migrants, best represented those reaching UK‐IR. The effect of geographical remoteness was negative – vagrants in NS were less likely to appear in UK‐IR. Population changes were important in predicting the 1956–2003 UK‐IR counts from 1955–80 FL counts. The seasonal characteristics, high explanatory power of the Fallout list and over‐representation of probable over‐ocean migrants in the standard regressions all support suggestions by others that many Nearctic vagrants in UK‐IR originate in flights off southeast USA and are displaced downwind across the North Atlantic.
The Complex Links between Governance and Biodiversity
Authors: BARRETT CHRISTOPHER B. , GIBSON CLARK C. , HOFFMAN BARAK , McCUBBINS MATHEW D.
Published: July 2006

Abstract:  We argue that two problems weaken the claims of those who link corruption and the exploitation of natural resources. The first is conceptual and the second is methodological. Studies that use national‐level indicators of corruption fail to note that corruption comes in many forms, at multiple levels, that may affect resource use quite differently: negatively, positively, or not at all. Without a clear causal model of the mechanism by which corruption affects resources, one should treat with caution any estimated relationship between corruption and the state of natural resources. Simple, atheoretical models linking corruption measures and natural resource use typically do not account for other important control variables pivotal to the relationship between humans and natural resources. By way of illustration of these two general concerns, we used statistical methods to demonstrate that the findings of a recent, well‐known study that posits a link between corruption and decreases in forests and elephants are not robust to simple conceptual and methodological refinements. In particular, once we controlled for a few plausible anthropogenic and biophysical conditioning factors, estimated the effects in changes rather than levels so as not to confound cross‐sectional and longitudinal variation, and incorporated additional observations from the same data sources, corruption levels no longer had any explanatory power.