bluuebunny/crossref_metadata_2025 huggingface dataset:
Diversity in anopheline larval habitats and adult composition during the dry and wet seasons in Ouagadougou (Burkina Faso)
Authors: Fournet Florence , Cussac Maud , Ouari Ali , Meyer Pierre-Erwann , Toé Hyacinthe K , Gouagna Louis-Clément , Dabiré Roch K
Published: April 2010

Background

Several cases of malaria are frequently recorded during the dry period in Ouagadougou town (Burkina Faso). This has led to the design of a series of studies focusing on both parasitological and entomological investigations intended to provide relevant health data on the risk of local malaria transmission according to the way of urbanisation.

Methods

A cross-sectional entomological survey was carried out in various districts of Ouagadougou in April and October 2006. Adult malaria vectors were collected using CDC traps and indoor insecticide spraying performed in four houses during four consecutive days/nights. Intensive larval sampling was also done in available water ponds throughout the study sites.

Results

In April, the anopheline breeding sites consisted only of semi-permanent or permanent swamps located mainly in the two peripheral districts. Despite the presence of anopheline larvae in these breeding sites, less than five Anopheles gambiae s.l. adults were caught by CDC traps and indoor insecticide spraying. In October, additionally to the permanent breeding sites reported in April, some rainfall swamps were also found positive to anophelines. The number of adults' mosquitoes was higher than that collected in April (2 vs 159 in October). Out of 115 larvae of An. gambiae s.l. analysed by PCR in April, 59.1% (68/115) were identified as Anopheles arabiensis, 39.1% (45/115) as An. gambiae M while the S form represented less than 2%. Overall 120 larvae and 86 females were identified by PCR in October as An. gambiae M form (51%) and An. arabiensis (42.2%). The S form represented only 6.8%. The global sporozoite rate recorded was high (6.8%) and did not differ between the districts except in the central district where no positive mosquito was detected.

Conclusion

Although only few adults' mosquitoes were actively caught during the driest month, malaria vectors persisted all year long that increases the risk of urban malaria transmission. The distribution of breeding sites and especially the occurrence of malaria vectors were more abundant in the periphery, which is more like that of a rural settlement. The evolution of malaria prevalence and the factors sustaining the risk of transmission in Ouagadougou as well in many African cities during the dry season are discussed.
The expression of syndecan-1, syndecan-4 and decorin in healthy human breast tissue during the menstrual cycle
Authors: Hallberg Gunilla , Andersson Eva , Naessén Tord , Ordeberg Gunvor Ekman
Published: April 2010

Background

In order to unravel the interactions between the epithelium and the extra cellular matrix (ECM) in breast tissue progressing to cancer, it is necessary to understand the relevant interactions in healthy tissue under normal physiologic settings. Proteoglycans in the ECM play an important role in the signaling between the different tissue compartments. The proteoglycan decorin is abundant in the breast stroma. Decreased expression in breast cancer tissue is a sign of a poor tumor prognosis. The heparane sulphate proteoglycans syndecan-1 and syndecan-4 promote the integration of cellular adhesion and proliferation. The aim of this study was to investigate the gene expression and location of decorin, syndecan-1 and syndecan-4 in the healthy breast during the menstrual cycle.

Methods

Tissue from healthy women undergoing breast reduction plastic surgery was examined using immunohistochemistry (n = 38) and Real-Time RT-PCR (n = 20). Both parous and nulliparous women were eligible and the mean age of the women was 34(+/- 10 years) with regular menstrual cycles (28 +/- 7 days). None of the women had used hormonal treatment the last three months. The women were randomized to needle biopsy two months before the operation in the follicular or luteal menstrual phase and for another biopsy at the operation in the opposite phase. Serum samples were obtained to characterize the menstrual phase. The Wilcoxon signed rank test and Mann Whitney test were used for statistical analyses.

Results

By real time-RT-PCR the gene signal for all three proteoglycans; decorin (p = 0.02) and syndecan-1 (p = 0.03) and syndecan-4 (p = 0.02) was significantly lower among parous women in the luteal phase than in the follicular phase. Immunohistochemistry confirmed the identification of the proteins but no significant difference between menstrual phases was observed. Serum samples verified the menstrual phase.

Conclusions

Our study shows, for the first time in the healthy breast, a significantly lower expression of the genes for the three proteoglycans, decorin, syndecan-1 and syndecan-4 in the luteal phase during the menstrual cycle. These changes were registered under normal physiologic conditions. Since ECM molecules appear to be involved in tumor progression, these findings in the normal breast could constitute a base for further studies in women receiving hormonal therapy or those with breast cancer.
A comparability study of 5 commercial KRAS tests
Authors: Oliner Kelly , Juan Todd , Suggs Sid , Wolf Michael , Sarosi Ildiko , Freeman Daniel J , Gyuris Tibor , Baron Will , Bakker Andreas , Parker Alex , Patterson Scott D
Published: April 2010

Background

Activating mutations in the KRAS gene occur frequently in human tumors, including colorectal carcinomas; most mutations occur in codons 12 and 13. Mutations in KRAS have been associated with poor response to anti-epidermal growth factor receptor antibodies. Therefore, an accurate and readily available analysis of KRAS mutational status is needed. The aim of this study was to evaluate concordance between KRAS assays performed by 6 different laboratories.

Methods

Forty formalin-fixed paraffin-embedded colorectal cancer tumor samples were obtained. Sample sections were submitted for KRAS mutation analysis to 5 independent commercial laboratories (Agencourt, Gentris, Genzyme, HistoGeneX, and Invitek) and to the Amgen DNA Sequencing Laboratory for direct polymerase chain reaction sequencing. The assay used by Invitek is no longer commercially available and has been replaced by an alternative technique. Results from the commercial services were compared with those from Amgen direct sequencing by κ statistics.

Results

KRAS mutations were observed in codon 12 and/or 13 in 20 of 40 (50%) samples in Amgen direct sequencing assays. Results from HistoGeneX (κ = 0.95), Genzyme (κ = 0.94), and Agencourt (κ = 0.94) were in almost perfect agreement with these results, and the results from Gentris were in substantial agreement with the results from Amgen (κ = 0.75). The Invitek allele-specific assay demonstrated slight agreement (κ = 0.13).

Conclusions

This study provides data on the comparability of KRAS mutational analyses. The results suggest that most (but not all) commercial services provide analysis that is accurate and comparable with direct sequencing.
Cancer risks of dermatomyositis and polymyositis: a nationwide cohort study in Taiwan
Authors: Chen Yi-Ju , Wu Chun-Ying , Huang Yu-Lin , Wang Chang-Bi , Shen Jui-Lung , Chang Yun-Ting
Published: April 2010

Introduction

The association of idiopathic inflammatory myositis (IIM) and malignancies has been reported, but rarely in Asian countries. Our aim was to investigate the risk of cancer among IIM patients without a prior history of malignancies, in Taiwan.

Methods

We conducted a nationwide cohort study of 1,012 patients with dermatomyositis (DM) and 643 patients with polymyositis (PM), but without prior history of malignancies, utilizing the National Health Insurance Database from 1997 to 2007. Standardized incidence ratios (SIRs) of cancers were analyzed.

Results

A total of 95 cancers (9.4%) in DM and 33 cancers (4.4%) in PM were identified. Overall cancer risk was significantly elevated in DM patients (SIR = 5.11, 95% confidence interval [CI] = 5.01 to 5.22) and PM patients (SIR = 2.15, 95% CI = 2.08 to 2.22). Most cancers were detected in the first year of observation. The risk of cancer decreased with observation time, yet remained elevated compared with the general population in both study groups after 5 years of follow-up. DM was associated with sustained elevated risk of cancers in every age group, whereas the risk of cancer in PM was highest in younger patients and decreased with age. DM patients were at the greatest risk of cancers of the nasopharynx, lungs and hematopoietic malignancies.

Conclusions

Patients with IIM are at increased risk for cancer and should receive age-appropriate and gender-appropriate malignancy evaluations, with additional assessment for nasopharyngeal, lung and hematologic malignancy following diagnosis, and with continued vigilance for development of cancers in follow-up.
Frequency tuning and intensity coding of sound in the auditory periphery of the lake sturgeon, Acipenser fulvescens
Authors: Meyer Michaela , Fay Richard R. , Popper Arthur N.
Published: April 2010

Acipenser fulvescens, the lake sturgeon, belongs to one of the few extant non-teleost ray-finned (bony) fishes. The sturgeons (family Acipenseridae) have a phylogenetic history that dates back about 250 million years. The study reported here is the first investigation of peripheral coding strategies for spectral analysis in the auditory system in a non-teleost bony fish. We used a shaker system to simulate the particle motion component of sound during electrophysiological recordings of isolated single units from the eighth nerve innervating the saccule and lagena. Background activity and response characteristics of saccular and lagenar afferents (such as thresholds, response–level functions and temporal firing) resembled the ones found in teleosts. The distribution of best frequencies also resembled data in teleosts (except for Carassius auratus, goldfish) tested with the same stimulation method. The saccule and lagena in A. fulvescens contain otoconia, in contrast to the solid otoliths found in teleosts, however, this difference in otolith structure did not appear to affect threshold, frequency tuning, intensity- or temporal responses of auditory afferents. In general, the physiological characteristics common to A. fulvescens, teleosts and land vertebrates reflect important functions of the auditory system that may have been conserved throughout the evolution of vertebrates.
Sonation in the male common snipe (Capella gallinago gallinagoL.) is achieved by a flag-like fluttering of their tail feathers and consequent vortex shedding
Authors: van Casteren A. , Codd J. R. , Gardiner J. D. , McGhie H. , Ennos A. R.
Published: April 2010

Male common snipe (Capella gallinago gallinago) produce a ‘drumming’ sound with their outer tail feathers during their mating dives, but little is known about how this is achieved. We investigated the movements and sound producing capabilities of the outer tail feathers. Using a wind tunnel, we compared observations of the frequencies of sound produced with the predictions from aerodynamic theory. The feathers were also filmed in an air-flow with a high speed video camera, and subjected to morphological examination and biomechanical testing. We propose a mechanistic hypothesis of how the modified outer feathers of the male common snipe generate sound, and the adaptations that facilitate this. Video and audio analysis of the feather demonstrated that a fluttering of the trailing vane generated the sound. The flutter of the vane is facilitated by the rearward curvature of the feather shaft, reduced branching angles of the barbs in the trailing vane and the lack of hooks on the barbs along a hinge region, all of which increase its flexural compliance. Sound production occurred at the same frequency as the vane movements, at frequencies consistent with it being produced by a fluttering flag mechanism powered by vortex shedding.
The functional morphology of hooding in cobras
Authors: Young Bruce A. , Kardong Kenneth V.
Published: April 2010

Many snakes, particularly cobras, form as part of a defensive display, a hood, an active lateral expansion of their neck skin and underlying musculature and ribs. We identified muscle groups possibly involved in hooding based on their attachments on the specialized ribs of the neck. We then used a combination of morphology, kinematic analysis, morphometrics, electromyography and muscle stimulation to test hypotheses about the functional basis of hooding. We confirmed that hood protraction and erection is an active process that begins cranially and extends caudally, often in stages, through the combined action of several sets of muscles. One set of axial muscles (levator costae and supracostalis lateralis superior) coursing along a line of action to rib displacement are the prime erectors acting to lift the hood. However, a second set of muscles connecting ribs to skin primarily keep the skin taut, rather than to displace the ribs relative to the vertebrae. A third set of muscles coursing between ribs function primarily to transmit forces between adjacent ribs rather than to move ribs. The maintenance of the erect hood requires continued muscle activity. Hood relaxation is due to both active muscle contraction of a fourth set of axial muscles and to passive recoil events in the costovertebral ligaments. The shape of the fully erect hood is reflective of the morphometrics of the underlying ribs, while the duration and kinematics of hood erection and relaxation are related to the behavioral context of the display.
Chitosan produces potent neuroprotection and physiological recovery following traumatic spinal cord injury
Authors: Cho Youngnam , Shi Riyi , Borgens Richard B.
Published: April 2010

Chitosan, a non-toxic biodegradable polycationic polymer with low immunogenicity, has been extensively investigated in various biomedical applications. In this work, chitosan has been demonstrated to seal compromised nerve cell membranes thus serving as a potent neuroprotector following acute spinal cord trauma. Topical application of chitosan after complete transection or compression of the guinea pig spinal cord facilitated sealing of neuronal membranes in ex vivo tests, and restored the conduction of nerve impulses through the length of spinal cords in vivo, using somatosensory evoked potential recordings. Moreover, chitosan preferentially targeted damaged tissues, served as a suppressor of reactive oxygen species (free radical) generation, and the resultant lipid peroxidation of membranes, as shown in ex vivo spinal cord samples. These findings suggest a novel medical approach to reduce the catastrophic loss of behavior after acute spinal cord and brain injury.
Aversiveness of sounds in phocid seals: psycho-physiological factors, learning processes and motivation
Authors: Götz Thomas , Janik Vincent M.
Published: April 2010

Aversiveness of sounds and its underlying physiological mechanisms in mammals are poorly understood. In this study we tested the influence of psychophysical parameters, motivation and learning processes on the aversiveness of anthropogenic underwater noise in phocid seals (Halichoerus grypus and Phoca vitulina). We compared behavioural responses of seals to playbacks of sounds based on a model of sensory unpleasantness for humans, sounds from acoustic deterrent devices and sounds with assumed neutral properties in different contexts of food motivation. In a captive experiment with food presentation, seals habituated quickly to all sound types presented at normalised received levels of 146 dB re. 1 μPa (r.m.s., root mean square). However, the fast habituation of avoidance behaviour was also accompanied by a weak sensitisation process affecting dive times and place preference in the pool. Experiments in the wild testing animals without food presentation revealed differential responses of seals to different sound types. We observed avoidance behaviour at received levels of 135–144 dB re. 1 μPa (sensation levels of 59–79 dB). In this experiment, sounds maximised for ‘roughness’ perceived as unpleasant by humans also caused the strongest avoidance responses in seals, suggesting that sensory pleasantness may be the result of auditory processing that is not restricted to humans. Our results highlight the importance of considering the effects of acoustic parameters other than the received level as well as animal motivation and previous experience when assessing the impacts of anthropogenic noise on animals.
Variation in the seasonal patterns of innate and adaptive immunity in the red-eared slider (Trachemys scripta)
Authors: Zimmerman Laura M. , Paitz Ryan T. , Vogel Laura A. , Bowden Rachel M.
Published: April 2010

The primary function of the immune system is to protect the organism from invading pathogens. In vertebrates, this has resulted in a multifaceted system comprised of both innate and adaptive components. The immune system of all jawed vertebrates is complex, but unlike the endothermic vertebrates, relatively little is known about the functioning of the ectothermic vertebrate immune system, especially the reptilian system. Because turtles are long-lived ectotherms, factors such as temperature and age may affect their immune response, but comprehensive studies are lacking. We investigated variation in immune responses of adult male and female red-eared sliders (Trachemys scripta) across the entire active season. We characterized seasonal variation in innate, cell-mediated and humoral components via bactericidal capacity of plasma, delayed-type hypersensitivity and total immunoglobulin levels, respectively. Results indicate that all immune measures varied significantly across the active season, but each measure had a different pattern of variation. Interestingly, temperature alone does not explain the observed seasonal variation. Immune measures did not vary between males and females, but immunoglobulin levels did vary with age. This study demonstrates the highly dynamic nature of the reptilian immune system, and provides information on how biotic and abiotic factors influence the immune system of a long-lived ectotherm.
Frequency coding of particle motion by saccular afferents of a teleost fish
Authors: Lu Zhongmin , Xu Zemin , Buchser William J.
Published: April 2010

The saccule is known to play an important role in hearing in fishes. In this study we investigated spatial frequency selectivity of single saccular afferents in a teleost fish (the sleeper goby, Dormitator latifrons) to acoustic particle motion at 50–400 Hz. Saccular afferents have similar distributions of best sensitivity (−90.0 to −54.8 dB re. 1 g, mean ± s.d.=−81.1±8.0 dB) and characteristic frequencies (≤50–400 Hz, median=80 Hz) along the longitudinal, side-to-side and dorsoventral axes of fish. They were lowpass, bandpass or broadly tuned to low frequencies with Q50% at 15 dB above threshold in ranges from 0.28 to 3.30 (1.46±0.71), 0.18 to 2.54 (1.36±0.78), and 0.41 to 4.26 (2.25±0.1.12) along the three axes, showing slightly greater frequency tuning in the vertical axis than horizontal axes. At supra threshold we found tuning plasticity, i.e. best frequencies of saccular afferents shifted to high frequencies as stimulus level increased. Isolevel rate–frequency curves were asymmetrical with shallow slopes at the low-frequency edge and steep slopes at the high-frequency edge. Saccular afferents of the sleeper goby have similar capabilities of coding particle motion frequencies in the three orthogonal axes. Results from this and other studies suggest that (1) the saccule is the major hearing organ in this species, (2) the saccule of this species is capable of encoding sound frequencies in three dimensional space, and (3) saccular afferents in fishes without accessory auditory structures exhibit similar frequency selectivity in response to particle motion.
Background colour matching by a crab spider in the field: a community sensory ecology perspective
Authors: Defrize Jérémy , Théry Marc , Casas Jérôme
Published: April 2010

The question of whether a species matches the colour of its natural background in the perspective of the correct receiver is complex to address for several reasons; however, the answer to this question may provide invaluable support for functional interpretations of colour. In most cases, little is known about the identity and visual sensory abilities of the correct receiver and the precise location at which interactions take place in the field, in particular for mimetic systems. In this study, we focused on Misumena vatia, a crab spider meeting the criteria for assessing crypsis better than many other models, and claimed to use colour changes for both aggressive and protective crypsis. We carried out a systematic field survey to quantitatively assess the exactness of background colour matching in M. vatia with respect to the visual system of many of its receivers within the community. We applied physiological models of bird, bee and blowfly colour vision, using flower and spider spectral reflectances measured with a spectroradiometer. We observed that crypsis at long distance is systematically achieved, exclusively through achromatic contrast, in both bee and bird visions. At short distance, M. vatia is mostly chromatically detectable, whatever the substrate, for bees and birds. However, spiders can be either poorly discriminable or quite visible depending on the substrate for bees. Spiders are always chromatically undetectable for blowflies. We discuss the biological relevance of these results in both defensive and aggressive contexts of crypsis within a community sensory perspective.
Hand and foot pressures in the aye-aye (Daubentonia madagascariensis) reveal novel biomechanical trade-offs required for walking on gracile digits
Authors: Kivell Tracy L. , Schmitt Daniel , Wunderlich Roshna E.
Published: April 2010

Arboreal animals with prehensile hands must balance the complex demands of bone strength, grasping and manipulation. An informative example of this problem is that of the aye-aye (Daubentonia madagascariensis), a rare lemuriform primate that is unusual in having exceptionally long, gracile fingers specialized for foraging. In addition, they are among the largest primates to engage in head-first descent on arboreal supports, a posture that should increase loads on their gracile digits. We test the hypothesis that aye-ayes will reduce pressure on their digits during locomotion by curling their fingers off the substrate. This hypothesis was tested using simultaneous videographic and pressure analysis of the hand, foot and digits for five adult aye-ayes during horizontal locomotion and during ascent and descent on a 30° instrumented runway. Aye-ayes consistently curled their fingers during locomotion on all slopes. When the digits were in contact with the substrate, pressures were negligible and significantly less than those experienced by the palm or pedal digits. In addition, aye-ayes lifted their hands vertically off the substrate instead of ‘toeing-off’ and descended head-first at significantly slower speeds than on other slopes. Pressure on the hand increased during head-first descent relative to horizontal locomotion but not as much as the pressure increased on the foot during ascent. This distribution of pressure suggests that aye-ayes shift their weight posteriorly during head-first descent to reduce loads on their gracile fingers. This research demonstrates several novel biomechanical trade-offs to deal with complex functional demands on the mammalian skeleton.
Triangular M/G/1-Type and Tree-Like Quasi-Birth-Death Markov Chains
Authors: Van Houdt Benny , van Leeuwaarden Johan S. H.
Published: April 2010

In applying matrix-analytic methods to M/G/1-type and tree-like quasi-birth-death (QBD) Markov chains, it is crucial to determine the solution to a (set of) nonlinear matrix equation(s). This is usually done via iterative methods. We consider the highly structured subclass of triangular M/G/1-type and tree-like QBD Markov chains that allows for an efficient direct solution of the matrix equation.
A field study of adult witness interviewing practices in a Canadian police organization
Authors: Snook Brent , Keating Kathy
Published: April 2010

Purpose. The current study examined witness interviewing practices in a Canadian police organization. The effect of interviewer, interviewee, and interview characteristics on those practices was also examined.

Method. Ninety witness interviews from a Canadian police organization were coded for the following interviewing practices: types of questions asked (i.e. open‐ended, probing, closed‐ended, clarification, multiple, leading, opinion/statement, and re‐asked), the number of interruptions, percentage of words spoken by interviewer, type of pre‐interview instructions (consequential vs. generic), and whether or not a free narrative was requested (and when requested during the interview). Characteristics pertaining to the interviewer (e.g. primary interviewer's age), interviewee (e.g. witness gender), and interview (e.g. crime type) were also coded.

Results. Results showed that closed‐ended and probing questions were the most widely asked questions, and that open‐ended questions were asked relatively infrequently. It was also found that the 80–20 talking rule was violated in 89% of the interviews, interviewers rarely interrupted the witnesses, and free narratives were requested often. Overall, the effect of interviewer, interview, or interviewee characteristics on interviewing practices was minimal.

Conclusions. The finding that scientifically prescribed interviewing practices are employed rarely by Canadian police officers highlights a need for increased professional interviewing training. The finding that practices are largely unaffected by personal and situational factors suggests that such training would be equally beneficial for all types of interviewers, interviewees, and contexts.
Moderation of Genetic Factors by Parental Divorce in Adolescents' Evaluations of Family Functioning and Subjective Wellbeing
Authors: van der Aa Niels , Boomsma Dorret I. , Rebollo-Mesa Irene , Hudziak James J. , Bartels Meike
Published: April 2010

Adolescents' evaluations of family functioning may have a significant impact on their subjective well-being and adjustment. The aim of the study was to investigate the degree to which genetic and environmental influences affect variation in evaluations of general family functioning, family conflict, and quality of life and the overlap between them. We assessed whether genetic and environmental influences are moderated by parental divorce by analyzing self-report data from 6,773 adolescent twins and their non-twin siblings. Genetic, shared, and nonshared environmental influences accounted for variation in general family functioning and family conflict, with genetic influences being relatively more important in girls than boys in general family functioning. Genetic and nonshared environmental influences accounted for variation in quality of life, with genetic influences being relatively more important in girls. Evidence was found for interaction between genetic factors and parental divorce: genetic influence on general family functioning was larger in participants from divorced families. The overlap between general family functioning and quality of life, and family conflict and quality of life was accounted for the largest part by genetic effects, with nonshared environmental effects accounting for the remaining part. By examining the data from monozygotic twins, we found evidence for interaction between genotype and nonshared, non-measured, environmental influences on evaluations of general family functioning, family conflict, and quality of life.
Twin Study of Heritability of Eating Bread in Danish and Finnish Men and Women
Authors: Hasselbalch Ann L. , Silventoinen Karri , Keskitalo Kaisu , Pietiläinen Kirsi H. , Rissanen Aila , Heitmann Berit L. , Kyvik Kirsten O. , Sørensen Thorkild I. A. , Kaprio Jaakko
Published: April 2010

Bread is an elementary part of the western diet, and especially rye bread is regarded as an important source of fibre. We investigated the heritability of eating bread in terms of choice of white and rye bread and use-frequency of bread in female and male twins in Denmark and Finland. The study cohorts included 575 Danish (age range 18–67 years) and 2009 Finnish (age range 22–27 years) adult twin pairs. Self-reported frequency of eating bread was obtained by food frequency questionnaires. Univariate models based on linear structural equations for twin data were used to estimate the relative magnitude of the additive genetic, shared environmental and individual environmental effects on bread eating frequency and choice of bread. The analysis of bread intake frequency demonstrated moderate heritability ranging from 37–40% in the Finnish cohort and 23–26% in the Danish cohort. The genetic influence on intake of white bread was moderate (24–31%), while the genetic influence on intake of rye bread was higher in men (41–45%) than in women (24–33%). Environmental influences shared by the twins were not significant. Consumption of bread as well as choice of bread is influenced by genetic predisposition. Environmental factors shared by the co-twins (e.g., childhood environment) seem to have no significant effects on bread consumption and preference in adulthood.
Optimization of Zygosity Determination by Questionnaire and DNA Genotyping in Chinese Adolescent Twins
Authors: Chen Jie , Li Xinying , Chen Zhiyan , Yang Xiaodong , Zhang Jie , Duan Qing , Ge Xiaojia
Published: April 2010

The main aim of this study was to develop and optimize a questionnaire-based zygosity determination method in Chinese adolescent twins. Participants were 471 pairs of same-sex twins (345 monozygotic, 126 dizygotic) with a mean age of 14.56 years (SD = 2.62). A second sample was recruited for cross-validation, including 382 pairs of same-sex twins (261 monozygotic, 121 dizygotic) with a mean age of 12.53 years (SD = 2.22). The questionnaire consisted of 12 questions dealing with co-twin similarity or frequency of confusion. Two means were put forward to improve the predictive accuracy of the questionnaire — adding parent-reports to the analysis, and using a 2-point rather than 3-point response format. DNA genotyping was performed on nine short tandem repeat loci, with an estimated zygosity classification accuracy very close to 100%. The validity of all questionnaires was assessed by being compared to the results of DNA analysis. Results of stepwise logistic regression analysis showed that the predictive accuracy of the 3-point self-reported questionnaire is 83.8%. Using parent-reports and 2-point scale led to 3.9% and 4.6% increase in predictive accuracy, respectively. When using the parent-reports and children's self-reports jointly, the predictive accuracy was enhanced to 90.6%. For the cross-validation, the equations and cut-offs derived from the first sample led to an acceptable accuracy (91.3%) in the second sample. In conclusion, the method we developed can be used in future studies among Chinese adolescent twins. Multiple-rater and 2-point response format were suggested for all twin studies for enhancing the predictive accuracy of questionnaires.
Population-Based Research: Breastfeeding Multiple Birth Infants / Twin Research Reviews and News: Perceived Aging in Twins; Separation of Conjoined Twins; School Placement Legislation / Twins in Education, Fashion and Humanitarian Events
Authors: Segal Nancy L.
Published: April 2010

The health benefits of breastfeeding are well known. However, less is known about the frequency and duration of breastfeeding in twins. A population-based study of maternal factors associated with the early cessation of breastfeeding in preterm and term twins is reviewed. This is followed by research reviews and news concerning aging in twins, conjoined twin separation and school legislation for multiple birth children. Twins and quadruplets who have distinguished themselves in the areas of education, fashion design and humanitarian efforts are highlighted.
Tumormarker beim Blasentumor: Aussichten für den klinischen Alltag / Tumor markers for bladder cancer: outlook for routine use
Authors: Ecke Thorsten H.
Published: April 2010

In diesem Artikel wird die aktuelle Rolle der Tumormarker beim Harnblasentumor in Diagnostik und Therapie vorgestellt. Die derzeit wichtigsten und interessantesten Tumormarker werden besonders hervorgehoben und ihr Einsatz für den klinischen Alltag diskutiert. Eine Medline-basierte Literaturrecherche wurde auf diesem Gebiet durchgeführt. Weitere Entwicklungen von Tumormarkern bei Rezidivtumoren und progressiven Krankheitsverläufen werden es in Zukunft möglich machen, Therapieoptionen für den einzelnen Patienten zu entwickeln. Molekulares Staging urologischer Tumoren kann Fälle selektieren, die von systemischen Therapien am besten profitieren. Es ist notwendig und wichtig, Grundlagenforschung und klinische Studien unter denselben Gesichtspunkten zu vereinen.
Oxidation Stability of Soy and Palm Based Biodiesels Evaluated by Pressure Differential Scanning Calorimetry
Authors: Artiaga Ramón , López-Beceiro Jorge , Tarrío-Saavedra Javier , Mier José L. , Naya Salvador , Gracia Carlos
Published: April 2010

The oxidation stabilizing effect of a substituted phenol on soy and palm based biodiesels was investigated according to the ASTM E2009 standard. Pressure differential scanning calorimetry (PDSC) measurements were used to evaluate the influence of oxygen pressure. A relationship was derived to describe the correlation between oxidation onset temperature and oxygen pressure. Additional standard differential scanning calorimetry (DSC) and thermogravimetric analysis tests were performed in order to evaluate other thermal effects of the additive. The different behavior of both fuels was explained on the basis of their different physical and chemical properties. PDSC results were compared with the values obtained by the Rancimat method and the crystallization temperature observed by standard DSC was compared with the cold filter plugging point obtained according to the EN 116 standard.
The adverse effects of obesity on conception and implantation
Authors: Brewer Christopher J , Balen Adam H
Published: April 2010

Whilst many multiparous women are obese (body mass index >30 kg/m2), obesity has been associated with impaired fecundity; however, the mechanism which links obesity to reduced fertility remains to be fully elucidated. Obese women, particularly those with central obesity, are less likely to conceive per cycle. Obese women suffer perturbations to the hypothalamic–pituitary–ovarian axis, menstrual cycle disturbance and are up to three times more likely to suffer oligo-/anovulation. A fine hormonal balance regulates follicular development and oocyte maturation, and it has been observed that obesity can alter the hormonal milieu. Leptin, a hormone produced by adipocytes, is elevated in obese women, and raised leptin has been associated with impaired fecundity. Obesity impairs ovulation but has also been observed to detrimentally affect endometrial development and implantation. The expression of polycystic ovary syndrome (PCOS) is regulated, in part, by weight, and so obese women with PCOS often have a more severe phenotype and experience more subfertility. Obesity also impairs the response of women to assisted conception treatments. Weight loss through lifestyle modification or bariatric surgery has been demonstrated to restore menstrual cyclicity and ovulation and improve the likelihood of conception. In this article, we will discuss the effect of obesity upon key reproductive mechanisms and its relation to fertility treatments.
Sex determination in mammalian germ cells: extrinsic versus intrinsic factors
Authors: Bowles Josephine , Koopman Peter
Published: April 2010

Mammalian germ cells do not determine their sexual fate based on their XX or XY chromosomal constitution. Instead, sexual fate is dependent on the gonadal environment in which they develop. In a fetal testis, germ cells commit to the spermatogenic programme of development during fetal life, although they do not enter meiosis until puberty. In a fetal ovary, germ cells commit to oogenesis by entering prophase of meiosis I. Although it was believed previously that germ cells are pre-programmed to enter meiosis unless they are actively prevented from doing so, recent results indicate that meiosis is triggered by a signaling molecule, retinoic acid (RA). Meiosis is avoided in the fetal testis because a male-specifically expressed enzyme actively degrades RA during the critical time period. Additional extrinsic factors are likely to influence sexual fate of the germ cells, and in particular, we postulate that an additional male-specific fate-determining factor or factors is involved. The full complement of intrinsic factors that underlie the competence of gonadal germ cells to respond to RA and other extrinsic factors is yet to be defined.
Immunoperoxidase technique using an anti-Leishmania (L.) chagasi hyperimmune serum in the diagnosis of culture-confirmed American tegumentary leishmaniasis
Authors: Quintella Leonardo P. , Cuzzi Tullia , Madeira Maria de F. , Okamoto Thais , Schubach Armando de O.
Published: April 2010

The present study reports the production of the rabbit anti-Leishmania (L.) chagasi hyperimmune serum, the standardization of the immunohistochemistry (IHC) technique and the evaluation of its employment in cutaneous leishmaniasis (CL) lesions diagnosed by Leishmania sp. culture isolation. Thirty fragments of active CL lesions were examined as well as 10 fragments of cutaneous mycosis lesions as control group. IHC proved more sensitive in detecting amastigotes than conventional hematoxylin-eosin (HE) stained slides: the former was positive in 24 (80%) biopsies whereas the latter, in 16 (53%) (p = 0.028). The reaction stained different fungus species causing cutaneous mycosis. Besides, positive reaction was noticed in mononuclear and endothelial cells. Nevertheless, this finding was present in the control group biopsies. It is concluded that IHC showed good sensitivity in detecting amastigotes.
Risk factors for and mortality of extended-spectrum-β-lactamase-producing Klebsiella pneumoniae and Escherichia coli nosocomial bloodstream infections
Authors: Superti Silvana Vargas , Augusti Gustavo , Zavascki Alexandre Prehn
Published: April 2010

A case-control study, involving patients with positive blood cultures for Klebsiella pneumoniae (KP) or Escherichia coli (EC) EC and controls with positive blood cultures for non-ESBL-KP or EC, was performed to assess risk factors for extended-spectrum-β-lactamase (ESBL) production from nosocomial bloodstream infections (BSIs). Mortality among patients with BSIs was also assessed. The study included 145 patients (81, 59.5% with K. pneumoniae and 64, 44.1% with E. coli BSI); 51 (35.2%) isolates were ESBL producers and 94 (64.8%) nonproducers. Forty-five (55.6%) K. pneumoniae isolates were ESBL producers, while only six (9.4%) E. coli isolates produced the enzyme. Multivariate analysis showed that recent exposure to piperacillin-tazobactam (adjusted Odds Ratio [aOR] 6.2; 95%CI 1.1-34.7) was a risk factor for ESBL BSI. K. pneumoniae was significantly more likely to be an ESBL-producing isolate than E. coli (aOR 6.7; 95%CI 2.3-20.2). No cephalosporin class was independently associated with ESBLs BSI; however, in a secondary model considering all oxymino-cephalosporins as a single variable, a significant association was demonstrated (aOR 3.7; 95%CI 1.3-10.8). Overall 60-day mortality was significantly higher among ESBL-producing organisms. The finding that piperacillin-tazobactam use is a risk factor for ESBL-production in KP or EC BSIs requires attention, since this drug can be recommended to limit the use of third-generation cephalosporins.
Immunoactivation and immunopathogeny during active visceral leishmaniasis
Authors: Goto Hiro , Prianti Maria das Graças
Published: April 2010

Visceral leishmaniasis is caused by protozoan parasites of the Leishmania donovani complex. During active disease in humans, high levels of IFN-γ and TNF-α detected in blood serum, and high expression of IFN-γ mRNA in samples of the lymphoid organs suggest that the immune system is highly activated. However, studies using peripheral blood mononuclear cells have found immunosuppression specific to Leishmania antigens; this poor immune response probably results from Leishmania antigen-engaged lymphocytes being trapped in the lymphoid organs. To allow the parasites to multiply, deactivating cytokines IL-10 and TGF-β may be acting on macrophages as well as anti-Leishmania antibodies that opsonize amastigotes and induce IL-10 production in macrophages. These high activation and deactivation processes are likely to occur mainly in the spleen and liver and can be confirmed through the examination of organ samples. However, an analysis of sequential data from studies of visceral leishmaniasis in hamsters suggests that factors outside of the immune system are responsible for the early inactivation of inducible nitric oxide synthase, which occurs before the expression of deactivating cytokines. In active visceral leishmaniasis, the immune system actively participates in non-lymphoid organ lesioning. While current views only consider immunocomplex deposition, macrophages, T cells, cytokines, and immunoglobulins by diverse mechanism also play important roles in the pathogenesis.
Human toxocariasis: contribution by Brazilian researchers
Authors: Chieffi Pedro Paulo , Santos Sérgio Vieira dos , Queiroz Maisa Leite de , Lescano Susana A. Zevallos
Published: April 2010

In the present paper the main aspects of the natural history of human infection by Toxocara larvae that occasionally result in the occurrence of visceral and/or ocular larva migrans syndrome were reviewed. The contribution by Brazilian researchers was emphasized, especially the staff of the Tropical Medicine Institute of São Paulo (IMT).
Epidemiology of neglected tropical diseases in transplant recipients: review of the literature and experience of a Brazilian HSCT center
Authors: Machado Clarisse Martins , Martins Talita Chaves , Colturato Iago , Leite Marília Souza , Simione Anderson João , Souza Mair Pedro de , Mauad Marcos Augusto , Colturato Vergílio Rensi
Published: April 2010

The rising success rate of solid organ (SOT) and haematopoietic stem cell transplantation (HSCT) and modern immunosuppression make transplants the first therapeutic option for many diseases affecting a considerable number of people worldwide. Consequently, developing countries have also grown their transplant programs and have started to face the impact of neglected tropical diseases (NTDs) in transplant recipients. We reviewed the literature data on the epidemiology of NTDs with greatest disease burden, which have affected transplant recipients in developing countries or may represent a threat to transplant recipients living in other regions. Tuberculosis, Leprosy, Chagas disease, Malaria, Leishmaniasis, Dengue, Yellow fever and Measles are the topics included in this review. In addition, we retrospectively revised the experience concerning the management of NTDs at the HSCT program of Amaral Carvalho Foundation, a public transplant program of the state of São Paulo, Brazil.
Chronic hepatitis C: hepatic iron content does not correlate with response to antiviral therapy
Authors: Pereira Patricia da Silva Fucuta , Silva Ivonete Sandra de Souza e , Uehara Silvia Naomi de Oliveira , Emori Christini Takemi , Lanzoni Valéria Pereira , Silva Antonio Eduardo Benedito , Ferraz Maria Lucia Gomes
Published: April 2010

The complex interaction between hepatitis C virus infection, iron homeostasis and the response to antiviral treatment remains controversial. The aim of this study was to evaluate the influence of hepatic iron concentration (HIC) on the sustained virological response (SVR) to antiviral therapy in patients with chronic hepatitis C. A total of 50 patients who underwent pretreatment liver biopsy with assessment of HIC by graphite furnace atomic absorption spectroscopy and were subsequently submitted to antiviral treatment with interferon/peginterferon and ribavirin were included in the study. Patients with alcoholism, history of multiple blood transfusion, chronic kidney disease, hemolytic anemia and parenteral iron therapy were excluded. The iron related markers and HIC were compared between those who achieved an SVR and non-responders (NR) patients. The mean age was 45.7 years and the proportion of patients' gender was not different between SVR and NR patients. The median serum iron was 138 and 134 µg/dL (p = 0.9), the median serum ferritin was 152.5 and 179.5 ng/mL (p = 0.87) and the median HIC was 9.9 and 8.2 µmol/g dry tissue (p = 0.51), for SVR and NR patients, respectively. Thus, hepatic iron concentration, determined by a reliable quantitative method, was not a negative predictive factor of SVR in patients with chronic hepatitis C presenting mild to moderate hepatic iron accumulation.
Circulation of antibodies against yellow fever virus in a simian population in the area of Porto Primavera Hydroelectric Plant, São Paulo, Brazil
Authors: Lima Maura Antonia , Romano-Lieber Nicolina Silvana , Duarte Ana Maria Ribeiro de Castro
Published: April 2010

Yellow fever (YF) is an acute viral infectious disease transmitted by mosquitoes which occurs in two distinct epidemiological cycles: sylvatic and urban. In the sylvatic cycle, the virus is maintained by monkey's infection and transovarian transmission in vectors. Surveillance of non-human primates is required for the detection of viral circulation during epizootics, and for the identification of unaffected or transition areas. An ELISA (enzyme-linked immunosorbent assay) was standardized for estimation of the prevalence of IgG antibodies against yellow fever virus in monkey sera (Alouatta caraya) from the reservoir area of Porto Primavera Hydroelectric Plant, in the state of São Paulo, Brazil. A total of 570 monkey sera samples were tested and none was reactive to antibodies against yellow fever virus. The results corroborate the epidemiology of yellow fever in the area. Even though it is considered a transition area, there were no reports to date of epizootics or yellow fever outbreaks in humans. Also, entomological investigations did not detect the presence of vectors of this arbovirus infection. ELISA proved to be fast, sensitive, an adequate assay, and an instrument for active search in the epidemiological surveillance of yellow fever allowing the implementation of prevention actions, even before the occurrence of epizootics.
Crystallographic Properties of Iridium
Authors: Arblaster John W.
Published: April 2010

The crystallographic properties of iridium at temperatures from absolute zero to the melting point are assessed following a review of the literature published during the period 1907 to date. However, the theoretical values above 2000 K are considered to be tentative because of the poor quality of the experimental thermal expansion data in this region. Selected values of the thermal expansion coefficient and measurements of length change due to thermal expansion have been used to calculate the variation with temperature of the lattice parameter, interatomic distance, atomic and molar volumes, and density. This data is presented in the Tables. Comparison of the data available in the literature with the selected values presented in this paper is shown in the Figures. The density of iridium at 293.15 K (20°C) is 22,562 kg m–3.