bluuebunny/crossref_metadata_2025 huggingface dataset:
Monitoring of lipid degradation products by solid‐phase microextraction*
Authors: Doleschall Fruzsina , Kemény Zsolt , Recseg Katalin , Kővári Katalin
Published: November 2004

The final sensory characteristic of vegetable oils is influenced by a series of aroma compounds and volatile oxidation products formed during storage and processing. Crude sunflower oil was stored at room temperature and was regularly refined by applying physical refining process in laboratory scale studying lipid degradation. Effect of long‐term storage and different steps of refining process on overall oxidative state and volatile compounds' formation was investigated by means of solid‐phase microextraction (SPME). Results were achieved by a 100‐μm polydimethylsiloxane fiber in the sample's headspace. Hexanal, tr‐2‐hexenal, tr‐2‐heptenal, tr‐2‐octenal, tr‐2‐nonenal, tr,tr‐2,4‐decadienal, α‐pinene, pentylfuran, 1‐octen‐3‐ol were used for external standard calibration. It was proved that hexanal and tr,tr‐2,4‐decadienal are aldehydes, which appear first in sunflower oil during long‐term storage. Detection limit using splitless injection and flame ionization detector was in 1–5 mg/kg depending on individual components. SPME was successfully applied for both controlling decomposition of hydroperoxides during bleaching and aldehydes removal during deodorization. SPME and traditional static headspace techniques were compared. Static headspace gave better recovery and lower detection limit for compounds having higher volatility, but SPME made it possible to measure higher molecular weight aldehydes providing a simple, reliable solution. © 2001 John Wiley & Sons, Inc. J Micro Sep 13: 215–220, 2001
Critical assessment of electrolyte systems for the capillary electrophoresis analysis of phenolic compounds in herbal extracts
Authors: Fonseca Fabiana Novaes , Kato Massuo Jorge , Oliveira Levi , Neto Nestor Pinto , Tavares Marina Franco Maggi
Published: November 2004

This work presents a comparative evaluation of electrolyte systems for the capillary electrophoresis analysis of the phenolic compounds apigenin and luteolin, and their corresponding 7‐O‐glucosides naringenin, rutin, quercetin, umbelliferone, herniarin, chlorogenic, and caffeic acids, in methanolic, glycolic, and hydroalcoholic extracts of Matricaria recutita L. (Asteraceae). The electrolytes included tetraborate buffer at different pHs and concentrations, containing varied amounts of sodium dodecyl sulfate, β‐cyclodextrin, and acetonitrile. The electrophoretic profile of the extracts changes considerably from electrolyte to electrolyte. However, in a single electrolyte, the profile of different extracts seems to be very similar (identical elution order), varying only in relative composition. The best condition for quantitative work was 20 mmol/L tetraborate buffer, pH 10, using direct detection at 337 nm. Baseline resolution of 9 among 11 selected standards was achieved readily in this electrolyte, showing distinct migration patterns for flavonoid aglycones (flavones, dihydroflavonols, and flavonols), coumarins, and acidic phenylpropanoids. To assure reproducibility, several capillary conditioning procedures were tested. Electrokinetic rinses with tetraborate buffer prior to sample injection gave the best results. Precision of migration times and peak areas were better than 4 and 2%, respectively, for 10 consecutive injections of the methanolic extract. A few method validation parameters also are reported, such as linearity (r2<0.999, concentration range from 5.0 to 75.0 μg/mL), limit of detection (3.8 μg/mL), and limit of quantitation (11.5 μg/mL), referred to apigenin, a commonly used compound to standardize chamomile extracts for topical use. Flavonoid glucosides that have distinct sugar moieties were separated readily in free solution; however, those with similar sugar moieties were separated only in micellar medium, using β‐cyclodextrin as the additive. The presence of reference compounds in the extracts was confirmed by spiking techniques and their identification was assisted by a UV‐spectra library. The validity of the diode array detector as an identification tool for phenolic compounds also is discussed. © 2001 John Wiley & Sons, Inc. J Micro Sep 13: 227–235, 2001
Optimization of solid phase microextraction analysis of aroma compounds in a Portuguese muscatel wine must
Authors: Vaz Freire Luís M. T. , Costa Freitas A. M. , Relva A. M.
Published: November 2004

The fundamental suitability of solid‐phase microextraction (SPME) has been investigated for the quantitative determination of eight aroma compounds present in a Portuguese muscatel wine must. The method has been optimized using a commercially available fiber coated with 85 μm polyacrylate (PA). The matrix effect was evaluated by comparing the results obtained with the standard additions method to those obtained, for the same analyte, by means of a calibration curve (internal standard method). The results obtained with the standard additions method show poor accuracy and higher confidence limits than those obtained by the calibration curve. Experiments during the SPME process were carried out to investigate the influence of (1) ethanol concentration and (2) high concentrations of one analyte on the absorption of minor components. No significant decrease in peak response was observed either for ethanol concentration from 3 to 12% or for excess concentration of one analyte over the others. The method was evaluated with respect to the linearity, within run precision and limit of detection. The curves obtained by plotting mass ratio vs. area ratio showed higher correlation coefficient R2>0.99 for most compounds. The use of internal standard minimizes quantitative errors due to the extraction process and injection. Ethanol concentration does not seem to affect quantitative determination. Polydimethylsiloxane (PDMS) fiber is more suitable for the analysis of esters, whereas polyacrylate is suitable for alcohols of low molecular weight and terpene quantification. The method has been applied to a Portuguese wine must to investigate the recovery of its aroma profile, formed by Saccharomyces cerevisiae during the wine‐must fermentation, using organophilic pervaporation [1]. © 2001 John Wiley & Sons, Inc. J Micro Sep 13: 236–242, 2001
Ion trap mass spectrometry as detector for capillary electrochromatography of peptides: Possibilities and limitations
Authors: Gaspari Marco , Guček Marjan , Walhagen Karin , Vreeken Rob J. , Verheij Elwin R. , Tjaden Ubbo R. , Van der Greef Jan
Published: November 2004

Capillary electrochromatography has been coupled to an ion trap mass spectrometer via a sheath flow electrospray interface. Peptide analysis was performed on 25 cm columns packed with C18‐bonded silica particles, and very fast separations were obtained. Full mass spectrometry and tandem mass spectrometry (MS/MS) detection were evaluated in terms of sensitivity and scanning speed. The separation of seven selected peptides and their detection by MS/MS in selected reaction monitoring mode was demonstrated. The performance of this sheath flow interface also was compared with the previously reported sheathless interface. Despite the loss in sensitivity (20–40‐fold), the sheath flow interface was shown to be superior in terms of ruggedness, and allowed the use of higher electric fields to achieve faster analysis times. © 2001 John Wiley & Sons, Inc. J Micro Sep 13: 243–249, 2001
Small broadband semicircular patch antenna with an L‐probe feeding
Authors: Guo Y. X. , Luk K. M. , Lee K. F.
Published: November 2004

Experimental results for an L‐probe‐fed shorted semicircular patch antenna are presented. Using a foam layer thickness ∼0.12λ0 as a supported substrate, an impedance bandwidth of 57% (SWR≤2) and a gain of over 4.0 dBi in the majority of the wide bandwidth have been obtained. The far‐field patterns are stable across the passband. © 2001 John Wiley & Sons, Inc. Microwave Opt Technol Lett 29: 289–290, 2001.
1‐D photonic bandgap resonator antenna
Authors: Serier C. , Cheype C. , Chantalat R. , Thèvenot M. , Monédière T. , Reineix A. , Jecko B.
Published: November 2004

This paper presents a theoretical method used to realize a 1‐D photonic bandgap (PBG) resonator antenna. Studies in the frequency and space domain were made to determine the properties of the material. Then a 1‐D PBG resonator antenna was designed, and some characteristics of the antenna were shown as the radiation pattern, the linear, and the circular polarization. The results show that such a device permits us to obtain high gain with a very thin structure. © 2001 John Wiley & Sons, Inc. Microwave Opt Technol Lett 29: 312–315, 2001.
Excitation of low‐profile equilateral‐triangular dielectric resonator antenna using a conducting conformal strip
Authors: Lo H. Y. , Leung K. W.
Published: November 2004

A new configuration that employs a conducting conformal strip to excite the low‐profile equilaterial‐triangular dielectric resonator antenna (DRA) of very high permittivity is proposed. As compared with the previous aperture‐coupling configuration, the new configuration has a wider impedance bandwidth (∼5.5%) and a higher front‐to‐back radiation ratio. The return loss, radiation patterns, and antenna gain are measured and discussed. © 2001 John Wiley & Sons, Inc. Microwave Opt Technol Lett 29: 317–319, 2001.
Genetic algorithms for the automatic synthesis of equivalent lumped‐element circuits
Authors: Selleri Stefano
Published: November 2004

The derivation of a lumped‐element equivalent circuit of a device is a fundamental topic in electronic and electromagnetic analysis. Here, a fully automatic genetic algorithm is devised and implemented to perform this task. The proposed method not only recovers the values of the lumped element, but also automatically synthesizes the topology of the equivalent circuit. © 2001 John Wiley & Sons, Inc. Microwave Opt Technol Lett 29: 356–359, 2001.
Electromagnetic scattering problems solved by an improved spectral iteration technique
Authors: Costanzo Sandra , Di Massa Giuseppe
Published: November 2004

The spectral iteration technique is used to solve electromagnetic scattering problems. A detailed analysis is carried out to investigate the convergence properties of the procedure, and a static solution is proposed as an initial estimate of the current to solve divergence problems. Diffraction by strips is considered to validate the method. © 2001 John Wiley & Sons, Inc. Microwave Opt Technol Lett 29: 384–388, 2001.
Frequency dependence of dielectric constant of construction materials in microwave and millimeter‐wave bands
Authors: Cuiñas Iñigo , Pugliese Jean‐Pierre , Hammoudeh Akram , García Sánchez Manuel
Published: November 2004

Results of experiments made to characterize the electromagnetic properties of typical building materials at 5.8 and 62.4 GHz are presented and compared. Transmission and reflection coefficients were measured as functions of the angle of incidence. A multiple successive internal reflection model was developed and used to estimate the dielectric constants by comparing measured and predicted values. It has been shown that, at a given frequency, the type of material used determines the value of its dielectric constant. The variation of the value of this constant with frequency does not necessarily follow the same trend for different materials. © 2001 John Wiley & Sons, Inc. Microwave Opt Technol Lett 30: 123–124, 2001.
Test adequacy criteria for UML design models
Authors: Andrews Anneliese , France Robert , Ghosh Sudipto , Craig Gerald
Published: November 2004

Systematic design testing, in which executable models of behaviours are tested using inputs that exercise scenarios, can help reveal flaws in designs before they are implemented in code. In this paper a technique for testing executable forms of UML (Unified Modelling Language) models is described and test adequacy criteria based on UML model elements are proposed. The criteria can be used to define test objectives for UML designs. The UML design test criteria are based on the same premise underlying code test criteria: coverage of relevant building blocks of models is highly likely to uncover faults. The test adequacy criteria proposed in this paper are based on building blocks for UML class and interaction diagrams. Class diagram criteria are used to determine the object configurations on which tests are run, while interaction diagram criteria are used to determine the sequences of messages that should be tested. Copyright © 2003 John Wiley & Sons, Ltd.
Systems engineering and cost as an independent variable
Authors: Brady Jim
Published: November 2004

The cost as an independent variable discipline is receiving increased emphasis in system design and development due to competitive pressure and the need to provide high performance products at lower cost. Successful implementation of this discipline depends on stakeholder buy‐in, effective communication, and application of the proper tools. The purpose of this article is to describe how and why CAIV belongs within the systems engineering area. Many of the processes involved are already being used by systems engineers including cost modeling, quality function deployment, and design for manufacturing and assembly. Integrating these and other standard tools into an effective cost reduction discipline is a job best performed by systems engineers. © 2001 John Wiley & Sons, Inc. Syst Eng 4: 233–241, 2001
Characterization of reproductive cycles and adrenal activity in the black‐footed ferret (Mustela nigripes) by fecal hormone analysis
Authors: Young K.M. , Brown J.L. , Goodrowe K.L.
Published: November 2004

The reproductive cycle of the black‐footed ferret (Mustela nigripes) was characterized by enzyme immunoassay (EIA) analysis of ovarian fecal steroids (estradiol, progestins) in 29 females over two consecutive breeding seasons. Estrous status was determined by measuring the vulva size and examining the percentage of superficial cells in vaginal lavages. Mean fecal estradiol concentrations were correlated with vulval area (r = 0.370, P < 0.0001) and the percentage of superficial cells (r = 0.380, P < 0.0001). Ovulation resulted in a rise in fecal progestin concentrations 5 days after breeding that differed (P < 0.05) between pregnant (n = 14) and pseudopregnant (n = 12) females during the late luteal phase (days 12–40), with concentrations remaining higher in pregnant animals. Gestation length was 41.3 ± 0.7 days with 3.6 ± 0.4 kits produced per female. Litter size correlated significantly (P < 0.05) with fecal estradiol, but not progestins during the 12 to 40 days after breeding. Females failing to breed (n = 3) remained in estrus for 31 ± 6.2 days before ovulation induction with human chorionic gonadotropin. Adrenal activity in male (n = 4) and female (n = 6) black‐footed ferrets was monitored by quantifying fecal corticoid metabolites after a series of manipulations (physical restraint, intramuscular saline, intramuscular gel adrenocorticotropic hormone (ACTH), intramuscular liquid ACTH). A significant (P < 0.0001) increase in fecal corticoids above the pre‐treatment baseline occurred 20 to 44 hours after restraint (five of 10 animals), saline (six of nine), gel ACTH (seven of 10), and liquid ACTH (nine of 10) treatments. Immunoreactivity of high‐performance liquid chromatography–separated fecal elutes was compared using antibodies against cortisol and corticosterone. The cortisol EIA demonstrated immunoreactivity that co‐eluted with 3H‐cortisol, whereas a corticosterone radioimmunoassay detected a metabolite peak that co‐eluted with 3H‐corticosterone in addition to a slightly less polar and one considerably more polar peak. Despite recognizing different metabolites, both assays produced similar temporal profiles of corticoid excretion after manipulation. This study provides new information on the black‐footed ferret regarding differences in fecal steroid excretion patterns between pregnancy and pseudopregnancy and the potential application of fecal corticoid metabolite monitoring for evaluating responses to stressors associated with practices used in breeding management. Zoo Biol 20:517–536, 2001. © 2002 Wiley‐Liss, Inc.
Chemical modification on lignocellulosic polymeric oil palm empty fruit bunch for advanced material
Authors: Zakaria Sarani , Hamzah Hazira , Murshidi Julie Andrianny , Deraman Mohamad
Published: November 2004

Oil palm fiber empty fruit bunch (EFB) was chemically treated with benzyl chloride (bz‐efb) and ethylene oxide (E‐efb) at different reaction temperatures (100 and 110°C for bz‐efb; 55, 85, and 92°C for E‐efb). The SEM micrographs of bz‐efb and E‐efb samples showed tremendous changes in morphological structure such as plastic properties as the reaction temperature was increased. The crystallinity (by XRD) and Tg of the reacted fibers were found to decrease as the reaction temperature increased. The FT‐IR of the reacted samples show that the chemical reactions have taken place between cellulose hydroxyl groups and bz‐efb and E‐efb, respectively. © 2001 John Wiley & Sons, Inc. Adv Polym Techn 20: 289–295, 2001
A comparison of anthropometric indices of nutritional status in Tukanoan and Achuar Amerindians
Authors: Orr Caley M. , Dufour Darna L. , Patton John Q.
Published: November 2004

Anthropometric data from a Tukanoan population in the Vaupes region of Colombia and an Achuar population in the Ecuadorian Amazon were compared relative to international references. The Tukanoans exploit an oligotrophic blackwater ecosystem, whereas the Achuar inhabit a resource rich montane ecosystem. Given this ecological distinction, three hypotheses regarding nutritional statuses were proposed: (1) Tukanoans are significantly shorter than the Achuar, indicating a greater degree of stunting; (2) Tukanoans are significantly leaner, indicating a greater degree of wasting; and (3) Tukanaons have significantly lower upper arm muscle area, indicating lower lean body mass. Z‐scores for height, weight‐for‐height, and estimated upper arm muscle area were determined and significant nutritional stress was assumed at z ≤ −2.0. Between population differences in z‐scores for height‐for‐age (ZHT), weight‐for‐height (ZWH), and upper arm muscle area (ZUMA) were examined using analysis of variance with a subsequent Scheffe's test. Between‐group differences in the frequencies of individuals with low z‐scores (z ≤ −2.0) were assessed via chi‐squared analysis. Both populations showed stunting in most age groups, but neither showed low ZWH or ZUMA. Significant differences between populations were found only for ZHT in children (females 1.0–4.9 and 5.0–9.9 years, and males 5.0–9.9 years). Tukanoans have significantly higher frequencies of stunting in all age‐sex groups except females and males age 30–49.9 years. There were no significant between‐population differences in the frequencies of individuals with low ZWH or ZUMA. These differences in nutritional status may reflect differences in resource availability. Am. J. Hum. Biol. 13:301–309, 2001. © 2001 Wiley‐Liss, Inc.
Prediction of adult stature for Japanese population: A stepwise regression approach
Authors: Ayub Ali MD. , Ohtsuki Fumio
Published: November 2004

The longitudinal growth in stature for 509 males and 311 females was characterized from early childhood to adulthood. A triphasic generalized logistic (BTT) model (Bock et al. [1994] Chicago: SSI) was used through the AUXAL software program. Growth parameters were derived from the estimated distance and velocity curves for each individual. A set of estimated growth parameters, including adult stature, was selected to develop equations, through the forward stepwise regression method, for the prediction of adult stature for Japanese boys and girls. Am. J. Hum. Biol. 13:316–322, 2001. © 2001 Wiley‐Liss, Inc.
Growth of children in two economically diverse Peruvian high‐altitude communities
Authors: Pawson Ivan G. , Huicho Luis , Muro Manuel , Pacheco Alberto
Published: November 2004

The growth of children living in two high‐altitude communities associated with an active copper mine in southern Peru was examined. In the community directly associated with mining operations, nutritional and health conditions were believed to be relatively favorable as a result of the substantial mine‐related infrastructure that had developed over the previous 12 years. In contrast, few such benefits were available in the other community, which provides limited part‐time labor at the mine. Anthropometric data, including measurements of height, weight, skinfold thicknesses, upper arm circumference, and chest dimensions, and determination of bone age, were collected from a total of 880 children between the ages of 4 and 18 years. There were significant differences between the two communities, with those in the mining community exhibiting significantly greater height and weight, a higher level of body fat, and more rapid skeletal development. Among children over the age of 12 years, a plateau in height was seen, suggesting that the benefits to growth resulting from mining‐related development were more noticeable in younger children. Compared with Peruvian high‐altitude populations examined during the 1960s, both samples from the present study were substantially taller and heavier, suggesting that despite local differences in socioeconomic conditions between the communities studied, overall conditions for growth are generally more favorable than those that existed among Peruvian high‐altitude populations surveyed in the 1960s. Am. J. Hum. Biol. 13:323–340, 2001. © 2001 Wiley‐Liss, Inc.
Variation in sexual dimorphism in relation to physical activity
Authors: Buffa Roberto , Marini Elisabetta , Floris Giovanni
Published: November 2004

The aim of this study was to examine variations in sexual dimorphism in relation to physical activity. A sample of 542 males and females (20–30 years), born and resident in Cagliari (Sardinia, Italy), was divided into two groups: active and inactive. Twenty‐five anthropometric dimensions were taken (weight, lengths, breadths, circumferences, and skinfolds). The circumferences and skinfolds were adjusted for the effects of overall body size (represented by skeletal variables). Body composition parameters—fat‐free mass (FFM), fat mass (FM), and arm muscular area (AMA)—were derived from the adjusted values. The D index (Bennett, 1981; Chakraborty and Majumder, 1982) was used to assess the degree of sexual dimorphism. The difference between the D values of active and inactive individuals was analyzed with the technique of Bennett (1981). Principal components analysis (PCA) was performed on groups of homogeneous variables (circumferences and skinfolds) in order to simplify the description of the original anthropometric data. The univariate and multivariate analyses indicate a greater sex difference in the group of individuals who are regularly active. The results agree with theoretical expectations, and suggest greater stability of women to environmental pressures (i.e., physical activity). Am. J. Hum. Biol. 13:341–348, 2001. © 2001 Wiley‐Liss, Inc.
Changes in adiposity and body mass index from late childhood to adult life in the Trois‐Rivières Study
Authors: Trudeau François , Shephard Roy J. , Arsenault François , Laurencelle Louis
Published: November 2004

This study explored tracking of the body mass index (BMI) in a representative subgroup of subjects (95 women and 96 men) who were involved in the Trois‐Rivières Growth and Development Study by testing autocorrelations between data for 10, 11, and 12 years and corresponding values at 34 years of age. Tracking of skinfold measurements (subscapular, triceps, suprailiac, and abdominal, and their sum) over the same intervals (60 women and 52 men) was also evaluated. After the age of 12 years, subjects showed a similar development of absolute values, whether they were from the experimental or the control group. Gains of the BMI and skinfold thicknesses showed expected gender differences. In particular, men showed larger gains of the BMI and abdominal skinfolds, whereas women had larger gains in the triceps skinfold. Increases in the sum of four skinfolds did not differ significantly between men and women, suggesting that the larger BMI gains in men were caused by a larger relative increase of fat‐free mass in the men. Tracking coefficients for the BMI were lower in men than in women between 10, 11, 12, and 34 years (r = 0.43–0.49 vs. r = 0.64–0.70, P < 0.001). The results indicate that the body composition of participants in the Trois‐Rivières Growth and Development study developed in a similar fashion whether or not their primary school instruction included additional physical education instruction. The results also suggest that prediction of adult obesity based on childhood BMI measurements is more effective in girls than in boys. Am. J. Hum. Biol. 13:349–355, 2001. © 2001 Wiley‐Liss, Inc.
Evidence on major gene control of cortical index in pedigree data from Middle Dalmatia, Croatia
Authors: Ginsburg Emil , Škarić‐Jurić Tatjana , Kobyliansky Eugene , Malkin Ida , Rudan Pavao
Published: November 2004

It was recently reported that the inheritance of the metacarpal cortical index (CI) in the Chuvashian population can be described in terms of a major gene (MG) model. By applying transmission probability tests, the hypothesis was accepted that not only baseline level of CI but also its sex‐specific dependence on age were under control of the same putative large‐effect gene. Using a pedigree sample from the population of the islands of Middle Dalmatia, Croatia (847 observed individuals in 278 pedigrees), data are presented to support the above findings. The following hypotheses were accepted: (i) inheritance of baseline CI in the Croatian population can be attributed to the effect of a MG responsible for about 42% of the variation; (ii) the same MG takes part in the control of the dependence of CI on age, particularly the age at onset of involutive bone changes (inflection point), and of the rate of decrease in CI with age (slope coefficient). Issues related to the assortative mating effect on CI and the determination of the most parsimonious model are discussed. Am. J. Hum. Biol. 13:398–408, 2001. © 2001 Wiley‐Liss, Inc.
Birth weight and parental PGM1 alleles
Authors: Gloria‐Bottini F. , Lucarini N. , La Torre M. , Lucarelli P. , Bottini E.
Published: November 2004

A deviation of the maternal–neonatal joint phosphoglucomutase locus 1 (PGM1) distribution from Hardy–Weinberg expectation has been reported. It was suggested that selection on PGM1 during intrauterine life might account for these deviations and that maternal and paternal PGM1 alleles might have different associations with intrauterine survival. This study considered possible associations between the joint mother–newborn PGM1 genotype and intrauterine growth. There was a significant association between birth weight percentile class and mother–newborn PGM1 genotype in infant females. Also, the paternal PGM1*2 allele was associated negatively with macrosomia, and this effect was significant only in female infants. Am. J. Hum. Biol. 13:417–420, 2001. © 2001 Wiley‐Liss, Inc.
Muscularity in adult humans: Proportion of adipose tissue‐free body mass as skeletal muscle
Authors: Wang Zimian , Heo Moonseong , Lee Robert C. , Kotler Donald P. , Withers Robert T. , Heymsfield Steven B.
Published: November 2004

Muscularity, or the proportion of adipose tissue‐free body mass (ATFM) as skeletal muscle (SM), provides valuable body composition information, especially for age‐related SM loss (i.e., sarcopenia). Limited data from elderly cadavers suggest a relatively constant SM/ATFM ratio, 0.540 ± 0.046 for men (mean ± SD, n = 6) and 0.489 ± 0.049 for women (n = 7). The aim of the present study was to examine the magnitude and constancy of the SM/ATFM ratio in healthy adults. Whole‐body SM and ATFM were measured using multi‐scan magnetic resonance imaging. The SM/ATFM ratio was 0.528 ± 0.036 for men (n = 139) and 0.473 ± 0.037 for women (n = 165). Multiple regression analysis indicated that the SM/ATFM ratio was significantly influenced by sex, age, body weight, and race. The four factors explained 50% of the observed between individual variation in the SM/ATFM ratio. After adjusting for age, body weight, and race, men had a larger SM/ATFM ratio than women. Both older men and women had a lower SM/ATFM ratio than younger subjects, although the relative reduction was greater in men. After adjustment for sex, age, and body weight, there were no significant differences in the SM/ATFM ratios between Asian, Caucasian, and Hispanic subjects. In contrast, African‐American subjects had a significantly greater SM/ATFM ratio than subjects in the other three groups. In addition, the SM/ATFM ratio was significantly lower in AIDS patients than corresponding values in healthy subjects. Am. J. Hum. Biol. 13:612–619, 2001. © 2001 Wiley‐Liss, Inc.
Tibetan protection from intrauterine growth restriction (IUGR) and reproductive loss at high altitude
Authors: Moore Lorna G. , Young David , McCullough Robert E. , Droma Tarshi , Zamudio Stacy
Published: November 2004

Chronic hypoxia at high altitude restricts fetal growth, reducing birth weight and increasing infant mortality. We asked whether Tibetans, a long‐resident high‐altitude population, exhibit less altitude‐associated intrauterine growth restriction (IUGR) and prenatal or postnatal reproductive loss than Han (ethnic Chinese), a group that has lived there for a shorter period of time. A population sample was obtained, comprising 485 deliveries to Tibetan or Han women over an 18‐month period at 8 general hospitals or clinics located at 2,700–4,700 m in the Tibet Autonomous Region, China. Birth weight, gestational age, and other information were recorded for each delivery. Prenatal and postnatal mortality were calculated using information obtained from all pregnancies or babies born to study participants. Tibetan babies weighed more than the Han, averaging 310 g heavier at altitudes 2,700–3,000 m (95% CI = 126, 494 g; P < 0.01) and 530 g heavier at 3,000–3,800 m (210, 750 g; P < 0.01). More Han than Tibetan babies were born prematurely. Prenatal and postnatal mortality rose with increasing elevation and were 3‐fold higher across all altitudes in the Han than the Tibetans (P < 0.05). Tibetans experience less altitude‐associated IUGR than Han and have lower levels of prenatal and postnatal mortality. When the relationships between birth weight and altitude are compared among these and other high‐altitude populations, those living at high altitude the longest have the least altitude‐associated IUGR. This may suggest the occurrence of an evolutionary adaptation. Am. J. Hum. Biol. 13:635–644, 2001. © 2001 Wiley‐Liss, Inc.
Intergenerational correlation of effective family size in early Québec (Canada)
Authors: Gagnon Alain , Heyer Evelyne
Published: November 2004

The use of a comprehensive demographic database of the early French Canadian population (1608–1800) reveals an almost null impact of parents' fertility on children's fertility (r ≃ 0.01–0.05), which contradicts the commonly held view that family size has a tendency to run in families. However, in this population, there is a clear transmission from one generation to the next of the effective family size within a given geographical area (EFS, defined as the number of children that settle per settled individual). Three types of correlations between EFS of parents and children are presented in order to account for the impact of socio‐demographic differentials. Individuals who belong to a large sibship and who settled in a given subdivision tend to encourage the settlement of a high number of their own children in the same subdivision (r ≃ 0.1–0.3). An additional correlation was introduced to see if geographically‐based differentials of EFS can account for the differential of founders' regional genetic contribution. The analysis shows that EFS correlation has a definite impact on the concentration of a population's gene pool (it increases it by ≃20%–45%), and partly accounts for the differences between subdivisions in this regard. Am. J. Hum. Biol. 13:645–659, 2001. © 2001 Wiley‐Liss, Inc.
Body mass index growth in a sample of U.S. children: Repeated measures data analysis of the minneapolis children's blood pressure study
Authors: Hlaing Wayway M. , Prineas Ronald J. , Zhu Yiliang , Leaverton Paul E.
Published: November 2004

Longitudinal assessments of the body mass index (BMI) in children and adolescents are limited. The purpose of the study was to describe the growth patterns of the BMI in children and young adults. Black and White children of Minneapolis Children's Blood Pressure Study (MCBPS) were 6 to 9 years old at entry and were followed for 12 years at 19 separate visits. Those with at least five visits (n = 1,302) were included for analysis, using non‐linear mixed effects models in conjunction with the Gompertz curve. The growth patterns of four sex‐ethnic groups were different at three levels: starting level (SL) (kg/m2), asymptote level (AL) (kg/m2), and peak growth age (PGA) (in years). In this context, SL is the average BMI level at age 6, AL is the average BMI level when growth diminishes, and PGA is the average age at which the rate of growth in the BMI peaks. The SL (16.3 ± 0.1) for White males was significantly greater than SL in the other three sex‐ethnic groups, among which there were no significant differences. There was a significant ethnic difference in AL between Black females (25.5 ± 0.3) and White females (24.4 ± 0.2) and a marginally significant difference in AL between Black females and Black males (24.4 ± 0.3). For PGA, only sex differences were significant: Black females reached the peak at the earliest age at (11.5 ± 0.1) years, followed by White females (11.7 ± 0.1), Black males (12.6 ± 0.1), and White males (12.8 ± 0.1). Am. J. Hum. Biol. 13:821–831, 2001. © 2001 Wiley‐Liss, Inc.
Absence of N‐acetylaspartate in the human brain: Impact on neurospectroscopy?
Authors: Martin Ernst , Capone Andrea , Schneider Jacques , Hennig Juergen , Thiel Thorsten
Published: November 2004

N‐acetylaspartate (NAA) contributes to the most prominent signal in proton magnetic resonance spectroscopy (1H‐MRS) of the adult human brain. We report the absence of NAA in the brain of a 3‐year‐old child with neurodevelopmental retardation and moderately delayed myelination. Since normal concentration of NAA in body fluids is hardly detectable, 1H‐MRS is a noninvasive technique for identifying neurometabolic diseases with absent NAA. This report puts NAA as a neuronal marker to question. Ann Neurol 2001;49:518–521
Subthalamic infusion of an NMDA antagonist prevents basal ganglia metabolic changes and nigral degeneration in a rodent model of Parkinson's disease
Authors: Blandini Fabio , Nappi Giuseppe , Greenamyre J. Timothy
Published: November 2004

Using permanent cannulas connected to subcutaneous pumps, we infused selective glutamate antagonists into the subthalamic nucleus of rats. Pumps were implanted immediately after the intrastriatal injection of 6‐hydroxydopamine and delivered micro‐quantities of the N‐methyl‐D‐aspartate antagonist MK‐801 or the α‐amino‐3‐hydroxy‐5‐methylisoxazole antagonist NBQX for 4 weeks. Subthalamic infusion of MK‐801, but not of NBQX, prevented the basal ganglia metabolic changes and motor abnormalities caused by nigrostriatal lesion. Animals treated with MK‐801 also exhibited marked reduction of nigral cell loss. We conclude that pharmacological modulation of subthalamic activity may have both symptomatic and neuroprotective effects in Parkinson's disease. Ann Neurol 2001;49:525–529
Germline mutations in the CCM1 gene, encoding Krit1, cause cerebral cavernous malformations
Authors: Lucas Miguel , Costa Alzenira F. , Montori Mariano , Solano Francisca , Zayas María D. , Izquierdo Guillermo
Published: November 2004

Mutations in the Krit1 gene have been recently discovered as the cause of hereditary cerebral cavernous angioma. We sought the possibility that de novo, noninherited mutations of Krit1 also cause cavernous angioma. A patient with two cerebral malformations carries a heterozygous deletion of two base pairs (741delTC) in exon VI of the Krit1 gene. The deletion initiates a frameshift mutation that, 23 amino acids downstream, encodes a TAA stop triplet replacing a CAT triplet of histidine at exon VII (H271X). Magnetic resonance images of the parents were normal, neither parent carries the 741delTC mutation, and both bear the wild‐type sequence of exon VI. These findings document a de novo germline mutation in Krit1 gene that causes cerebral cavernous malformations. Ann Neurol 2001;49:529–532
Late‐onset metachromatic leukodystrophy clinically presenting as isolated peripheral neuropathy: Compound heterozygosity for the IVS2+1G→a mutation and a newly identified missense mutation (Thr408Ile) in a Spanish family
Authors: Comabella Manuel , Waye John S. , Raguer Nuria , Eng Barry , Domínguez Carmen , Navarro Carmen , Borrás Cecilia , Krivit William , Montalbán Xavier
Published: November 2004

We report the case of a 50‐year‐old woman and her 32‐year‐old daughter, both of whom are affected with adult‐onset metachromatic leukodystrophy (MLD) clinically presenting as peripheral neuropathy. Arylsulfatase A (ARSA) activities were markedly reduced, and electrophysiology showed a severe demyelinating neuropathy with features of chronic acquired demyelinating polyneuropathy. Molecular genetic studies of the family revealed that the proband and her affected daughter are compound heterozygotes for the common IVS2+1G→A mutation and a newly identified missense mutation, Thr408Ile. This case indicates that adult metachromatic leukodystrophy should be considered in adult patients with demyelinating peripheral neuropathy of unknown etiology.
A disorder similar to Huntington's disease is associated with a novel CAG repeat expansion
Authors: Margolis Russell L. , O'Hearn Elizabeth , Rosenblatt Adam , Willour Virginia , Holmes Susan E. , Franz Mary L. , Callahan Colleen , Hwang Hyon S. , Troncoso Juan C. , Ross Christopher A.
Published: November 2004

Huntington's disease (HD) is an autosomal dominant disorder characterized by abnormalities of movement, cognition, and emotion and selective atrophy of the striatum and cerebral cortex. While the etiology of HD is known to be a CAG trinucleotide repeat expansion, the pathways by which this mutation causes HD pathology remain unclear. We now report a large pedigree with an autosomal dominant disorder that is clinically similar to HD and that arises from a different CAG expansion mutation. The disorder is characterized by onset in the fourth decade, involuntary movements and abnormalities of voluntary movement, psychiatric symptoms, weight loss, dementia, and a relentless course with death about 20 years after disease onset. Brain magnetic resonance imaging scans and an autopsy revealed marked striatal atrophy and moderate cortical atrophy, with striatal neurodegeneration in a dorsal to ventral gradient and occasional intranuclear inclusions. All tested affected individuals, and no tested unaffecteds, have a CAG trinucleotide repeat expansion of 50 to 60 triplets, as determined by the repeat expansion detection assay. Tests for the HD expansion, for all other known CAG expansion mutations, and for linkage to chromosomes 20p and 4p were negative, indicating that this mutation is novel. Cloning the causative CAG expansion mutation for this new disease, which we have termed Huntington's disease‐like 2 (HDL2), may yield valuable insight into the pathogenesis of HD and related disorders.
Molecular heterogeneity of myophosphorylase deficiency (Mcardle's disease): A genotype‐phenotype correlation study
Authors: Martín Miguel A. , Rubio Juan C. , Buchbinder Jenny , Fernández‐Hojas Roberto , Del Hoyo Pilar , Teijeira Susana , Gámez Josep , Navarro Carmen , Fernández José M. , Cabello Ana , Campos Yolanda , Cervera Carlos , Culebras José M. , Andreu Antoni L. , Fletterick Robert , Arenas Joaquín
Published: November 2004

We report on 54 Spanish patients with McArdle's disease from 40 unrelated families. Molecular analysis revealed that the most common R49X mutation was present in 70% of patients and 55% of alleles. The G204S mutation was less frequent and found in 14.8% of patients and 9% of mutant alleles. The W797R mutation was observed in 16.5% of patients, accounting for 13.7% of mutant alleles. Moreover, 78% of mutant alleles among Spanish patients can be identified by using polymerase chain reaction‐restriction fragment length polymorphism analysis for the R49X, G204S, and W797R mutations, which makes noninvasive diagnosis possible through molecular genetic analysis of blood DNA. Six novel mutations were found. Three were missense mutations, E348K, R601W, and A703V; two nonsense mutations, E124X and Q754X; and one single base pair deletion, 533 delA. No clear genotype‐phenotype correlation emerges from our study. Most of the mutations of uncharged and solvent inaccessible residues and the truncations must disrupt the basic structure of the protein. The mutations of charged residues would be expected to interfere with internal hydrogen bonding networks, introducing severe incompatible partnering that is caused by poor packing or electrostatic repulsions.
Increased incidence of sporadic Creutzfeldt‐Jakob disease on the island of Crete associated with a high rate of PRNP 129‐methionine homozygosity in the local population
Authors: Plaitakis Andreas , Viskadouraki Anna K. , Tzagournissakis Minas , Zaganas Ioannis , Verghese‐Nikolakaki Susan , Karagiorgis Vasilis , Panagiotides Ioannis , Kilindireas Constantine , Patsouris Eustratios , Haberler Christine , Budka Herbert , Sklaviadis Theodoros
Published: November 2004

Since the spring of 1997, when the Neurology Department of the University Hospital of Crete admitted its first patient, 9 cases (8 neuropathologically confirmed and 1 probable) of sporadic Creutzfeldt‐Jakob disease (sCJD) have been recorded. This represents an annual incidence five‐fold higher than expected based on the island's population (0.54 million). Molecular analysis of the prion‐protein gene (PRNP) showed no mutations in any of the seven CJD cases studied. Five patients (ages 64–88 years) were homozygous for methionine‐129 of PRNP and showed the classic sCJD triad (subacute dementia, myoclonus, periodic electroencephalogram). Brains contained Type 1 (unglycosylated 21.5 kDa band) protease‐resistant prion protein (PrPres). Two patients (ages 56 and 57 years), both homozygous for valine‐129, showed cerebellar ataxia and later dementia not associated with periodic electroencephalogram; brain PrPres was Type 2. Genotyping of 205 Cretan controls showed that methionine‐129 homozygosity, a susceptibility factor for sCJD, was significantly higher in this population than in other Caucasian populations (57.0%, n = 205 versus 41.5%, n = 859. These data are the first to relate a high regional incidence rate for sCJD to the distribution of PRNP 129 genotypes in the local population; however, additional factors may be operational.
Biochemical variations in the synaptic level of dopamine precede motor fluctuations in Parkinson's disease: PET evidence of increased dopamine turnover
Authors: De La Fuente‐Fernández Raúl , Lu Jian‐Qiang , Sossi Vesna , Jivan Salma , Schulzer Michael , Holden James E. , Lee Chong S. , Ruth Thomas J. , Calne Donald B. , Stoessl A. Jon
Published: November 2004

Motor fluctuations are a major disabling complication in the treatment of Parkinson's disease. To investigate whether such oscillations in mobility can be attributed to changes in the synaptic levels of dopamine, we studied prospectively patients in the early stages of Parkinson's disease with a follow‐up after at least 3 years of levodopa treatment. At baseline, 3 positron emission tomography (PET) scans using [11C]raclopride before and after (1 hour and 4 hours) orally administered levodopa were performed on the same day for each patient. Patients who developed “wearing‐off” fluctuations during the follow‐up period had a different pattern of levodopa‐induced changes in [11C]raclopride binding potential (BP) from that observed in patients who were still stable by the end of the follow‐up. Thus, 1 hour post‐levodopa the estimated increase in the synaptic level of dopamine was 3 times higher in fluctuators than in stable responders. By contrast, only stable responders maintained increased levels of synaptic dopamine in the PET scan performed after 4 hours. These results indicate that fluctuations in the synaptic concentration of dopamine precede clinically apparent “wearing‐off” phenomena. The rapid increase in synaptic levels of dopamine observed in fluctuators suggests that increased dopamine turnover might play a relevant role in levodopa‐related motor complications. Ann Neurol 2001;49:298–303
Corticotropin (ACTH) acts directly on amygdala neurons to down‐regulate corticotropin‐releasing hormone gene expression
Authors: Brunson Kristen L. , Khan Najeeb , Eghbal‐Ahmadi Mariam , Baram Tallie Z.
Published: November 2004

The hormone corticotropin (ACTH) is employed as therapy for diverse neurological disorders, but the mechanisms for its efficacy remain unknown. ACTH promotes the release of adrenal steroids (glucocorticoids), and most ACTH effects on the central nervous system (CNS) have been attributed to activation of glucocorticoid receptors. However, in several human disorders, ACTH has therapeutic actions that differ qualitatively or quantitatively from those of steroids. This study tested the hypothesis that ACTH directly influences limbic neurons via the recently characterized melanocortin receptors and focused on the effects of ACTH on the expression of corticotropin‐releasing hormone (CRH), a neuropeptide involved in neuroimmune functions and in certain developmental seizures. The results demonstrated that ACTH potently reduced CRH expression in amygdala neurons. This down‐regulation was not abolished by experimental elimination of steroids or by blocking their receptors and was reproduced by a centrally administered ACTH fragment that does not promote steroid release. Importantly, selective blocking of melanocortin receptors prevented ACTH‐induced down‐regulation of CRH expression. Taken together, these data indicate that ACTH activates central melanocortin receptors to modulate CRH gene expression in amygdala, supporting the notion that direct, steroid‐independent actions of ACTH may account for some of its established clinical effects on the CNS. Ann Neurol 2001;49:304–312
Genome scan of idiopathic generalized epilepsy: Evidence for major susceptibility gene and modifying genes influencing the seizure type
Authors: Durner Martina , Keddache Mehdi A. , Tomasini Livia , Shinnar Shlomo , Resor Stanley R. , Cohen Jeffrey , Harden Cynthia , Moshe Solomon L. , Rosenbaum David , Kang Harriet , Ballaban‐Gil Karen , Hertz Sharon , Labar Douglas R. , Luciano Daniel , Wallace Sibylle , Yohai David , Klotz Irene , Dicker Elisa , Greenberg David A.
Published: November 2004

Idiopathic generalized epilepsy (IGE) is a common, complex disease with an almost exclusively genetic etiology but with variable phenotypes. Clinically, IGE can be divided into different syndromes. Varying lines of evidence point to the involvement of several interacting genes in the etiology of IGE. We performed a genome scan in 91 families ascertained through a proband with adolescent‐onset IGE. The IGEs included juvenile myoclonic epilepsy (JME), juvenile absence epilepsy (JAE), and epilepsy with generalized tonic clonic seizures (EGTCS). Our linkage results support an oligogenic model for IGE, with strong evidence for a locus common to most IGEs on chromosome 18 (lod score 4.4/5.2 multipoint/two‐point) and other loci that may influence specific seizure phenotypes for different IGEs: a previously identified locus on chromosome 6 for JME (lod score 2.5/4.2), a locus on chromosome 8 influencing non‐JME forms of IGE (lod score 3.8/2.5), and, more tentatively, two newly discovered loci for absence seizures on chromosome 5 (lod scores 3.8/2.8 and 3.4/1.9). Our data also suggest that the genetic classification of different forms of IGE is likely to cut across the clinical classification of these subforms of IGE. We hypothesize that interactions of different combinations of these loci produce the related heterogeneous phenotypes seen in IGE families. Ann Neurol 2001;49:328–335