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Summary Introduction This report presents a synopsis of a three‐part, cross‐sector, seminar series held at the George Washington University (GWU) in Washington, DC from February–April, 2018. The overarching goal of the seminar series was to provide a neutral forum for diverse stakeholders to discuss and critically evaluate approaches to address added sugar intake, with a key focus on the role of low‐calorie sweeteners (LCS). Methods During three seminars, twelve speakers from academic institutions, federal agencies, non‐profit organizations, and the food and beverage industries participated in six interactive panel discussions to address: 1) Do Farm Bill Policies Impact Population Sugar Intake? 2) What is the Impact of Sugar‐sweetened Beverage (SSB) Taxes on Health and Business? 3) Is Sugar Addictive? 4) Product Reformulation Efforts: Progress, Challenges, and Concerns? 5) Low‐calorie Sweeteners: Helpful or Harmful, and 6) Are Novel Sweeteners a Plausible Solution? Discussion of each topic involved brief 15‐minute presentations from the speakers, which were followed by a 25‐minute panel discussion moderated by GWU faculty members and addressed questions generated by the audience. Sessions were designed to represent opposing views and stimulate meaningful debate. Given the provocative nature of the seminar series, attendee questions were gathered anonymously using Pigeonhole™, an interactive, online, question and answer platform. Results This report summarizes each presentation and recapitulates key perspectives offered by the speakers and moderators. Conclusions The seminar series set the foundation for robust cross‐sector dialogue necessary to inform meaningful future research, and ultimately, effective policies for lowering added sugar intakes.

Cultivated pepper is a rich source of diverse bioactive compounds with potential properties related to the prevention of major degenerative and proliferative diseases. In the present study, 15 sweet pepper varieties, highly appreciated on the Italian market, were assessed for variation in the content of ascorbic acid, isoprenoids and flavonoids, as well as morpho-agronomic performances and molecular diversity.; Results: The collection under study showed a wide variability for all traits considered. Traditional cultivars, although less productive, were characterized by a high content of β-carotene and ascorbic acid, reaching maximum concentrations of 230.5 mg kg-1 fresh weight (fw) and 2750 mg kg-1 fw, respectively. Strong correlations were demonstrated between neoxanthin and luteolins. Fruit weight was positively correlated with α-tocopherol content and negatively correlated with luteolins content. The genotyping by sequencing platform allowed the identification of 1833 single nucleotide polymorphism, which better defined the relationships among cultivars, based on provenance and improvement rate.; Conclusions: The present study provides an overview of the variability in the expression of fruit nutritional traits in a collection of horn-shaped pepper cultivars, integrating agronomic and molecular data. The impact for breeding and consumers is discussed. © 2017 Society of Chemical Industry.; © 2017 Society of Chemical Industry.

The average American child eats fewer fruits than recommended. Although taste is the primary motivator for food intake among children, little research has systematically measured children's liking of fruit and determined whether their preferences differ from adults. We phenotyped 49 children and their mothers to determine: (1) their liking of the taste of 3 blueberry cultivars (“Arcadia,” “Keecrisp,” and “Kestrel”) from 2 harvests for which total soluble solids were determined using a handheld Brix refractometer; (2) the association between liking and blueberry sugar content; and (3) the most preferred level of fructose, one of the primary sugars in blueberry fruit. Multiple methods, identical for all participants, assessed which cultivar they liked best. Dietary intake, determined via 24‐h dietary recall, revealed most children (73%) and adults (92%) did not meet dietary guidelines for fruit intake. We found that during the 1st harvest, Keecrisp was sweeter by 4° Brix than either Arcadia or Kestrel and was the cultivar most preferred by both children and adults. For the 2nd harvest, mothers liked each of the cultivars equally, but children preferred Arcadia, which was 2° Brix sweeter than the other 2 cultivars. Like other sugars, children's most preferred concentration of fructose was significantly higher than that of adults. In sum, children appear to be more sensitive to smaller variations in sweetness than are adults. Identifying drivers of fruit preference and assessing children's liking for whole fruits are important steps in developing strategies to increase fruit consumption among children. Although taste is the primary motivator for food intake among children, little research has systematically measured children's liking of fruit and determined whether their preferences differ from adults. In this farm‐to‐sensory‐lab study, we used multiple methods to assess liking for the taste of 3 blueberry cultivars picked during the beginning of the Florida blueberry season. We found that children prefer higher levels of fructose and appear to be more sensitive to small changes in the sugar content of blueberry fruit than did adults. These findings provide insight into the child consumer and highlights the potential for consumer‐driven breeding to produce fruit accepted by young children.

Objective: This review summarizes a portion of the discussions of an NIH Workshop (Bethesda, MD, 2015) titled “Self-Regulation of Appetite—It's Complicated,” which focused on the biological aspects of appetite regulation. Methods: This review summarizes the key biological inputs of appetite regulation and their implications for body weight regulation. Results: These discussions offer an update of the long-held, rigid perspective of an “adipocentric” biological control, taking a broader view that also includes important inputs from the digestive tract, from lean mass, and from the chemical sensory systems underlying taste and smell. It is only beginning to be understood how these biological systems are integrated and how this integrated input influences appetite and food eating behaviors. The relevance of these biological inputs was discussed primarily in the context of obesity and the problem of weight regain, touching on topics related to the biological predisposition for obesity and the impact that obesity treatments (dieting, exercise, bariatric surgery, etc.) might have on appetite and weight loss maintenance. Finally considered is a common theme that pervaded the workshop discussions, which was individual variability. Conclusions: It is this individual variability in the predisposition for obesity and in the biological response to weight loss that makes the biological component of appetite regulation so complicated. When this individual biological variability is placed in the context of the diverse environmental and behavioral pressures that also influence food eating behaviors, it is easy to appreciate the daunting complexities that arise with the self-regulation of appetite.

Steroid hormones activate nuclear receptors which, as transcription factors, can regulate critical aspects of neural development. Many regions of the rat forebrain, midbrain and hindbrain express progestin receptors (PR) during perinatal life, suggesting that progesterone may play an important role in the development of the brain. An immunohistochemical approach using two antibodies with differential recognition of ligand-bound PR was used to examine whether fetuses are exposed to maternal progesterone during pregnancy and whether progesterone from maternal circulation can bind to PR within the fetal brain. Findings demonstrate that maternal and fetal serum progesterone levels are positively correlated at the end of gestation, suggesting a common source of progesterone in mothers and fetuses (e.g., the maternal ovary). Additional findings suggest that administration of exogenous progesterone to mothers not only increases fetal serum progesterone levels within 2 h, but appears to increase ligand-bound PR in fetal brain. These findings suggest that progesterone of maternal origin may play a previously overlooked role in neural development. In addition, there are implications for the ongoing prophylactic use of synthetic progestins in pregnant women for the prevention of premature birth. © 2016 Wiley Periodicals, Inc. Develop Neurobiol 77: 767-774, 2017.

This article summarizes research findings from 6 experts in the field of taste and feeding that were presented at the 2015 American Society for Parenteral and Enteral Nutrition Research Workshop. The theme was focused on the interaction of taste signals with those of a postingestive origin and how this contributes to regulation of food intake through both physiological and learning processes. Gastric bypass results in exceptional loss of fat mass and increases in circulating levels of key gut peptides, some of which are also expressed along with their cognate receptors in taste buds. Changes in taste preference and food selection in both bariatric surgery patients and rodent models have been reported. Accordingly, the effects of this surgery on taste-related behavior were examined. The conservation of receptor and peptide signaling mechanisms in gustatory and extraoral tissues was discussed in the context of taste responsiveness and the regulation of metabolism. New findings detailing the features of neural circuits between the caudal nucleus of the solitary tract (NST), receiving visceral input from the vagus nerve, and the rostral NST, receiving taste input, were discussed, as was how early life experience with taste stimuli and learned associations between flavor and postoral consequences of nutrients can exert potent and long-lasting effects on feeding.

The double burden of under- and overnutrition profoundly affects human health globally. According to the World Health Organization, obesity and diabetes rates have almost doubled worldwide since 1980, and, in 2011, more than 40 million children under 5 years of age were overweight. Ecologic factors, parental genetics and fitness, and the intrauterine environment significantly influence the likelihood of offspring developing the dysmetabolic diathesis of obesity. This report examines the effects of these factors, including preconception, intrauterine and postnatal energy balance affecting programming of transgenerational transmission, and development of chronic diseases later in life-in particular, diabesity and its comorbidities.

Objective: This review summarizes a portion of the discussions of an NIH Workshop (Bethesda, MD, 2015) titled “Self-Regulation of Appetite—It's Complicated,” which focused on the biological aspects of appetite regulation. Methods: This review summarizes the key biological inputs of appetite regulation and their implications for body weight regulation. Results: These discussions offer an update of the long-held, rigid perspective of an “adipocentric” biological control, taking a broader view that also includes important inputs from the digestive tract, from lean mass, and from the chemical sensory systems underlying taste and smell. It is only beginning to be understood how these biological systems are integrated and how this integrated input influences appetite and food eating behaviors. The relevance of these biological inputs was discussed primarily in the context of obesity and the problem of weight regain, touching on topics related to the biological predisposition for obesity and the impact that obesity treatments (dieting, exercise, bariatric surgery, etc.) might have on appetite and weight loss maintenance. Finally considered is a common theme that pervaded the workshop discussions, which was individual variability. Conclusions: It is this individual variability in the predisposition for obesity and in the biological response to weight loss that makes the biological component of appetite regulation so complicated. When this individual biological variability is placed in the context of the diverse environmental and behavioral pressures that also influence food eating behaviors, it is easy to appreciate the daunting complexities that arise with the self-regulation of appetite.

Objectives Understanding the dynamics of feeding is essential for preventing accelerated weight gain during infancy, a risk factor for obesity. Because infants satiate on larger volumes of cow milk formula (CMF) than CMF enriched with the free amino acid glutamate (CMF+glu), we used this model system to determine whether infants displayed consistent behaviors despite satiating on lower volumes.

We present the analyses results of two bulk Terminal Particles, C2112,7,171,0,0 and C2112,9,171,0,0, derived from the Jupiter-family comet 81P/Wild 2 returned by the Stardust mission. Each particle embedded in a slab of silica aerogel was pressed in a diamond cell. This preparation, as expected, made it difficult to identify the minerals and organic materials present in these particles. This problem was overcome using a combination of three different analytical techniques, viz. FE-SEM/EDS, IR, and Raman microspectroscopy that allowed identifying the minerals and small amounts of amorphous carbon present in both particles. TP2 and TP3 were dominated by Ca-free and low-Ca, Mg-rich, Mg,Fe-olivine. The presence of melilite in both particles is supported by IR microspectroscopy, but is not confirmed by Raman microspectroscopy, possibly because the amounts are too small to be detected. TP2 and TP3 show similar silicate mineral compositions, but Ni-free and low-Ni, subsulfur (Fe,Ni)S grains are present in TP2 only. TP2 contains indigenous amorphous carbon hot spots; no indigenous carbon was identified in TP3. These nonchondritic particles probably originated in a differentiated body. This work found an unanticipated carbon contamination following the FE-SEM/EDS analyses. It is suggested that organic materials in the embedding silica aerogel are irradiated during FE-SEM/EDS analyses creating a carbon gas that develops a strong fluorescence continuum. The combination of the selected analytical techniques can be used to characterize bulk Wild 2 particles without the need of extraction and removal of the encapsulating aerogel. This approach offers a relatively fast sample preparation procedure, but compressing the samples can cause spurious artifacts, viz. silica contamination. Because of the combination of techniques, we account for these artifacts.

Objective Smoking and obesity are independently associated with high consumption of high-fat foods in women. We tested whether the co-occurrence of smoking and obesity associates with reduced oral fat perception. Methods Four groups of women (14 obese smokers, 11 obese never-smokers, 10 normal-weight smokers, 12 normal-weight never-smokers) rated vanilla puddings that varied in fat content for perceived intensity of creaminess and sweetness, using the general Labeled Magnitude Scale (gLMS), and degree of pleasantness, using the hedonic gLMS. To determine the role of retronasal smell, subjects rated puddings with and without noseclips. Results For all groups, perception of creaminess grew with increasing fat concentrations; puddings with any amount of fat were perceived as sweeter than fat-free pudding, and sweetness was enhanced when tasted without noseclips. Overall, obese smokers perceived less creaminess, sweetness, and pleasure while tasting the puddings than did the other three groups (all P values

Steroid hormones largely exert their actions by activating nuclear receptors, which, as transcription factors, powerfully influence fundamental processes of neural development. Often, steroid receptor action demonstrates remarkable specificity under different developmental, anatomical or hormonal conditions. Yet, the mechanisms underlying such specificity are poorly understood. The present study examined the anatomically-specific regulation of progestin receptor (PR) expression by oestrogen receptor (ER) activation in the ventromedial nucleus (VMN) of the hypothalamus and the medial preoptic nucleus (MPN) of the neonatal female rat brain, using the selective oestrogen receptor modulators (SERMs), tamoxifen and ICI 182780 (ICI), in the presence or absence of oestradiol benzoate (EB) treatment. The results demonstrate that PR immunoreactivity (PR-ir) in the neonatal female MPN was significantly increased by EB and this increase was abolished by either tamoxifen or ICI treatment. In contrast, within the VMN of the same animals, EB had no effect on PR-ir and the SERMs only modestly decreased PR-ir. Interestingly, ICI acted as a true antagonist regardless of EB treatment, whereas tamoxifen acted as an ER agonist in the absence of EB in the MPN, but not the VMN, representing one of the first in vivo demonstrations of tissue-specific and oestradiol-independent effects of tamoxifen on ER activation. The present results indicate that PR expression is highly dependent on oestradiol and its receptor in the MPN, although it is independent of both oestradiol and ER activation within the neonatal VMN. These findings demonstrate the anatomically-specific actions of oestradiol and its receptor to induce PR in two brain regions controlling different aspects of female reproductive behaviours in adulthood.

Rat testis H1 proteins were poly(ADP-ribosyl)ated in vitro. The modifying product, poly(ADP-ribose), was found covalently bound to each histone variant at various extents and exhibited distinct structural features (linear and short, rather than branched and long chains). Interest was focused on the somatic H1a, particularly abundant in the testis, as compared with other tissues, and the testis-specific H1t, which appears only at the pachytene spermatocyte stage of germ cell development. These H1s were modified with poly(ADP-ribose) by means of two in vitro experimental approaches. In the first system, each variant was incubated with purified rat testis poly(ADP-ribose)polymerase in the presence of [(32)P] NAD. In parallel, poly(ADP-ribosyl)ated H1s were also prepared following incubation of intact rat testis nuclei with [(32)P] NAD. In both experiments, the poly(ADP-ribosyl)ated proteins were purified from the native forms by means of phenyl boronic agarose chromatography. The results from both analyses were in agreement and showed qualitative differences with regard to the poly(ADP-ribose) covalently associated with H1a and H1t. Comparison of the bound polymers clearly indicated that the oligomers associated with H1a were within 10-12 units long, whereas longer chains (

Although smell loss has several potential etiologies (e.g., head trauma, allergic rhinitis, and enlarged adenoids) that are common among children, studies evaluating the prevalence of olfactory dysfunction in the pediatric population are rare. Several challenges confront the clinician or researcher hoping to evaluate odor identification ability in young children. Children are likely to be unfamiliar with many of the odor stimuli used in adult tests and have limited ability to read and identify labels to select from alternative choices, which is the typical adult response option. Consequently, specialized forms of olfactory tests must be developed for this population. Based on the format of the San Diego Odor Identification Test(1) and the delivery system of the Brief Smell Identification Test,(2) we are developing a short form odor identification test utilizing standardized odor stimuli in which participants match 6 odorants to pictures of the odor source. The pilot version of this test is being administered to children between the ages of 3-17 as part of the pre-surgical intake evaluation at the A.I. duPont Hospital for Children and as part of basic research studies at the Monell Center. The hospital study population is broad and includes children undergoing ear, nose, and throat surgery as well as controls subjects (children undergoing general surgery), with approximately 50 children per week eligible for evaluation. To improve correct interpretation of the results, stimulus familiarity is evaluated by having the child's parent/guardian also complete the test and answer a short questionnaire about the child's experience with the various odor stimuli. The challenges confronted in studying this clinical population as well as extrapolation to larger populations will be discussed.

The 7kDa Sso7 is a basic protein particularly abundant in Sulfolobus solfataricus and is involved in DNA assembly. This protein undergoes in vitro ADP-ribosylation by an endogenous poly(ADP-ribose) polymerase-like enzyme. The circular dichroism spectrum of purified ADP-ribosylated Sso7 shows that this modification stabilizes the prevalent protein β-conformation, as suggested by shifting of negative ellipticity minimum to 220nm. Moreover, a short ADP-ribose chain (up to 6-mers) bound to Sso7 is able to reduce drastically the thermoprotective and DNA condensing ability of the protein, suggesting a possible regulatory role of ADP-ribosylation in sulfolobal DNA organization.

We report combined micro-infrared, micro-Raman, and field emission scanning electron microscope (FESEM) analyses of particles collected by the Stardust spacecraft during its flyby of comet 81P/Wild 2 on 2 January 2004 and successfully returned back to Earth on 15 January 2006. We present mid-infrared (IR) spectra of six of these particles. The CH2/CH3 ratios inferred from the infrared data are greater than those seen in organics in the diffuse interstellar medium, possibly indicating the presence of longer or less branched aliphatic chains. The micro-Raman data offer insights into the state of the order of the carbonaceous component present in the particles. Raman parameters for most of the particles span a similar range to that observed in interplanetary dust particles (IDPs) and the most primitive meteorites. Both the IR and Raman data imply the presence of a very labile carbonaceous component. Hydrated silicates may be present in two particles of Track 35, one of which may also contain carbonates, but further investigations with other techniques need to be performed to confirm these findings. In some cases, the analyses are difficult to interpret because of the presence of compressed aerogel mixed with the grains.

A wide variety of drugs, including alcohol (da-Silva et al., 1993; Kesaniemi, 1974; Lawton, 1985; Mennella and Beauchamp, 1991), enter breastmilk and affect the lactational processes of milk production and the behavior and physiology of the recipient infant (Dorman et al., 2001; Hale et al., 2004; Little et al., 1989; Mennella and Beauchamp, 1991; Mennella et al., 2005). Much less is known about how the dynamic physiological processes that occur during lactation influence the absorption, distribution, and elimination of drugs and how such changes in drug pharmacokinetics impact the health of lactating women (Dan et al., 1993; Mitani et al., 1987; Nahum et al., 2006). Several lines of evidence from human and animal models support the hypothesis that lactational state could alter drug pharmacokinetics. First, the growth of the mammary glands during lactation provides a new compartment of drug distribution, excretion (Clewell and Gearhart, 2002), and possibly metabolism as alcohol dehydrogenase (ADH) is expressed in breast tissue (Saleem et al., 1984; Triano et al., 2003). Second, the high nutritional demands associated with milk production coincide with remarkable changes in the gastrointestinal tract (Hammond, 1997; Hunt and Murray, 1958; Uvnas-Moberg et al., 1987). In rodents, lactation is associated with dramatic intestinal growth (e.g., increased height of the villi) and a generalized hypertrophy and hyperplasia of the mucosal epithelium (Hammond, 1997). Such lactation-induced changes in the gastrointestinal tract significantly extend the surface area of the intestines, which, in turn, may modulate nutrient as well as drug absorption. Third, the act of nursing results in a surge of hormones (e.g., oxytocin) and gastrointestinal regulatory peptides that modifies the rate of gastric emptying (Franceschini et al., 1990; Holst et al., 1986; Ohlsson et al., 2004; Uvnas-Moberg et al., 1987; Widstrom et al., 1984; Winberg, 2005) and, in turn, may modify the pharmacokinetics of a variety of orally administered drugs including alcohol (Oneta et al., 1998; Pang, 2003). Fourth, the hypertrophy of the liver (da-Silva et al., 1996; DeSantiago et al., 1998; Gordon et al., 1985), and altered liver enzyme levels and liver functioning during lactation (David et al., 2000; Tigas et al., 2002) may affect the liver’s oxidative capacity and, in turn, alter drug metabolism. For example, it has been suggested that the lactation-induced liver hypertrophy contributes to the significantly faster rate at which alcohol is eliminated in lactating when compared with nonlactating rats (Abel et al., 1979; Gordon et al., 1985). Similarly, reproductive state may alter the activity of enzymes (e.g., ADH, microsomal ethanol oxidizing system) responsible for the metabolism of alcohol in the liver as well as other sites (Badger et al., 2005; Gordon et al., 1985). Information on alcohol pharmacokinetics during lactation in humans is limited to one study of 5 lactating women and 8 nonlactating control women. Three of the women in the control group were tested within months of stopping breastfeeding and the parity of the other 5 was not reported. Nevertheless, the data revealed that blood alcohol levels peaked later and the mean area under the blood alcohol time curve (AUC), an indicator of systemic availability of the drug, was significantly smaller in lactating women (da-Silva et al., 1993). However, unlike that observed in rodents (Abel et al., 1979), there were no significant differences in alcohol elimination rates. The lack of differences in alcohol disappearance rates may be due to the lack of appropriate control groups or statistical power because of the limited sample size or both. Therefore, the hypothesis that alcohol is eliminated at a faster rate during lactation cannot be rejected. Given the physiological adaptations of the digestive system during lactation (Hammond, 1997; Hunt and Murray, 1958; Uvnas-Moberg et al., 1987), the present study tested the hypotheses that lactation alters alcohol pharmacokinetics and that the metabolic differences between lactating and nonlactating women would be more striking when analyzing alcohol pharmacokinetics when alcohol was consumed with a meal. To this end, we studied lactating women who were exclusively breast feeding a 2- to 5-month-old infant and 2 control groups of nonlactating women under 2 conditions: when alcohol was consumed following a meal or on an empty stomach. The first control group consisted of women who were exclusively formula-feeding similarly aged infants, whereas the other consisted of women who had never given birth. These 2 control groups were included to determine whether differences, if any, observed between the groups were due to lactation per se and not a consequence of the physiological changes that occur during pregnancy and parturition. Subjective ratings of mood and drug effects during the rising and falling portions of the blood alcohol concentration (BAC) time curve were also obtained to determine whether reproductive state was associated with changes in the biphasic effects of alcohol.

The rat testis chromatin fractions (soluble, S, and insoluble, P) were prepared by mild digestion of nuclei with DNAase I. They appeared to be different in specific biochemical features such as their transcriptional competence and protein patterns, the latter indicating according to results previously obtained, that the testis-specific H1t is preferentially associated to the soluble fraction, whereas the other H1 variants are localized in the pellet. S and P chromatins also differed in the distribution of the poly(ADP-ribosyl)ating system, (poly(ADP-ribose)polymerase, reaction product and acceptor proteins), detected by incubating nuclei with 32P-NAD. The 32P-modified H1s and core histones of both fractions, known as specific ADPribose target proteins, were separated by high performance liquid chromatography and it was demonstrated that the H1 variants from S and P are differently ADPribosylated, being H1t always the best acceptor, and that most of the ADPribosylated variants were solubilized after DNase I treatment. The further digestion of P chromatin with the nuclease produced a fraction (pP) devoid of most DNA, but particularly enriched in transcriptionally competent tracts. The low DNA content of pP chromatin, which reflects the typical feature of a nuclear matrix, corresponded to a relevant poly(ADPribosyl)ation, the highest as compared to S and P fractions. Moreover, long and branched chains of poly(ADP-ribose) were found associated to pP sample which resemble the products determined in the soluble chromatin.

Interplanetary dust particles (IDPs) and meteorites provide a unique opportunity to study extraterrestrial materials in the laboratory. Different Raman studies have shown that most of IDPs exhibit the characteristic amorphous carbon Raman feature. Different degrees of order have been recognized in the amorphous carbon phase of IDPs, testifying either to different origins or to different processing under different physical conditions (temperature, pressure, etc.). This paper presents a comparison between the amorphous carbon Raman features of IDPs and those of carbon dust analogues obtained in the laboratory by ion irradiation of carbon-containing frozen gases and by arc discharge. We propose a possible mechanism able to induce an ‘evolution’ of IDPs. In particular, amorphous carbon with different degrees of order could be indicative of different irradiation doses by solar wind particles and fast solar protons suffered by IDPs in the interplanetary medium before collection in the Earth's atmosphere. Copyright © 2004 John Wiley & Sons, Ltd.

The palatability of oral medications, many of which are quite bitter, plays an important role in achieving compliance in pediatric patients. We tested the hypothesis that the addition of a sodium salt to some, but not all, bitter tasting liquids enhances acceptance and reduces the perceived bitterness in 7- to 10-year-old children and their mothers. For both children and adults, sodium gluconate significantly suppressed the perceived bitterness and enhanced the acceptance of urea and caffeine whereas the reverse was true for another bitter stimulus, Tetralone. Because children preferred salted solutions more than did adults, these data suggest that the use of sodium salts may be an especially effective strategy for reducing the bitterness of some medicines and facilitating compliance among pediatric populations. However, based on sodium’s differential ability to inhibit bitterness, as has been shown here with children and adults, clearly each drug of interest must be evaluated separately.

A chromatin fraction, named pP fraction, was prepared from rat testis nuclei, which had been digested with nuclease in order to separate soluble and insoluble chromatin. This fraction resembled nuclear matrix as it was highly resistant to DNAase digestion, had a high content of proteins compared to the low DNA percentage, and a noticeable transcriptional activity. Moreover, poly(ADPribosyl)ation system (i.e., poly(ADPR)polymerase, poly(ADPribose), and acceptor proteins) was still present at high levels. In order to study whether it might be identified as the protein support surrounding chromatin loops, this pP fraction was further analyzed after 3 M NaCl extraction. The 3 M NaCl extract and the highly insoluble pellet, named Nuclear Matrix Pellet, were characterized as it regards DNA, newly synthesized RNA and proteins. Furthermore, poly(ADPribose) metabolism was analyzed by measuring both poly(ADPribose) polymerase and poly(ADPribose) glycohydrolase activities, poly(ADPribose) distribution and by identifying protein acceptors. The final pellet had features of nuclear matrix containing less than 10% DNA and high percentage of proteins; 28% of newly synthesized RNA was still associated with this fraction. Long and branched polyADPribose were found in the nuclear matrix-like pellet, although ADPribose acceptors (mainly H1 and core histones) appeared to be modified mostly with short ADPribose oligomers. Longest and branched polymers were retained on the top of protein gel, likely bound to automodified poly(ADPribose) polymerase. J. Cell. Biochem. 89: 688–697, 2003. © 2003 Wiley-Liss, Inc.

The poly(ADPribose) polymerase-like thermozyme from the hyperthermophilic archaeon S. solfataricus was found to bind DNA with high affinity and non-specifically. Binding was independent of base composition and length of the nucleic acid, and the protein showed a slight preference for the circular structure. By using pCMV-Neo-Bam plasmid as experimental model, the behaviour of the thermozyme upon binding with either circular or linear plasmid was analyzed. pCMV-Neo-Bam has a single HindIII site that allows to obtain the linear structure after digestion with the restriction enzyme. Intrinsic tryptophan-dependent fluorescence of poly(ADPribose) polymerase-like thermozyme noticeably changed upon addition of either circular or linear plasmid, showing the same binding affinity (K=2 x 10(9) M-1). However, experiments of protection against temperature and DNase I gave evidence that the thermozyme formed more stable complexes with the circular structure than with the linear pCMV-Neo-Bam. Increasing temperature at various DNA/protein ratios had a double effect to reduce the amount of circular DNA undergoing denaturation and to split the melting point towards higher temperatures. Nil or irrelevant effect was observed with the linear form. Similarly, DNase acted preferentially on the linear plasmid/protein complexes, producing an extensive digestion even at high protein/DNA ratios, whereas the circular plasmid was protected by the thermozyme in a dose-dependent manner. The complexes formed by archaeal poly(ADPribose) polymerase (PARPss) with the circular plasmid were visualized by bandshift experiments both with ethidium bromide staining and by labelling the circular plasmid with 32P. The stability of complexes was tested as a function of enzyme concentration and in the presence of a cold competitor and of 0.1% SDS. From the performed experiments, a number of 3-10 base pairs bound per molecule of enzyme was calculated, indicating a high frequency of binding. The presence of circular DNA was also able to increase by 80% the poly(ADPribose)polymerase-like activity, as compared to 25% activation induced by the linear pCMV-Neo-Bam.

Objective Contrary to the folklore which claims that drinking alcohol during lactation benefits both mother and infant, previous research in our laboratory revealed that breastfed infants consumed significantly less milk during the immediate hours after their mothers' consumption of an alcoholic beverage. Because breastfed infants are clearly capable of regulating milk intake, the present study tested the hypothesis that infants would compensate for the diminished milk intake if their mothers then refrained from drinking alcohol. Methods A within-subjects design that controlled for time of day was implemented because of the great individual and daily variation in both milk composition and intake. To this end, 12 exclusively breastfed infants and their mothers were tested on 2 days separated by 1 week. Each woman drank a 0.3 g/kg dose of alcohol in orange juice on one testing day and orange juice alone on the other; the order was counterbalanced. The infants' behaviors were monitored for the next 16 hr, the first 4 hr of monitoring on each test day occurred at the Monell Center. The infants fed on demand and immediately before and after each feeding, infants were weighed without a change in clothing. Results Consistent with previous findings, infants consumed significantly less milk during the 4 hr immediately after exposure to alcohol in mothers' milk compared with the control condition. Compensatory increases in intake were then observed during the 8 to 16 hr after exposure when mothers refrained from drinking alcohol. Conclusions These findings demonstrate that short-term exposure to small amounts of alcohol in mothers' milk produces distinctive changes in the infants' patterns of feeding.

Colorado potato beetle (Leptinotarsa decemlineata Say) adult longevity and fecundity were studied on transgenic potato clones expressing a Cry3B endotoxin of Bacillus thuringiensis (Bt). Adult longevity and fitness were studied for the first 3 weeks after emergence. Beetle reproductive biology on highly resistant clones, intermediary resistant clones and control potato plants was monitored by dissecting females after 7–15 days of feeding and also by analysing haemolymph protein content after 3 days of feeding. Feeding behaviour on transgenic plants expressing high toxin concentrations and on control plants was monitored individually for 36 newly emerged adult beetles feeding on leaf disks during the first two meals. Lethal Time50 for adult beetles feeding on transgenic clones as the sole source of food was not significantly shorter than for beetles on control clones reared in a growth chamber. Differences tended to be larger when the experiment was conducted in a greenhouse with a less optimal temperature range (LT50= 9.52 and 10.45 days for two transgenic clones and 13.86 for control). In contrast, female egg production on transgenic plants was almost totally inhibited. Dissection studies indicated that adult males living on high-level Bt-expressing transgenic potatoes were still able to mate and produce mobile sperm, but the females were impaired in their reproductive ability since their ovaries were generally not fully developed. An examination of the haemolymph revealed the protein concentration in females living on transgenic plants to be dramatically reduced (≅ 50%), and electrophoresis showed a reduced content of vitellogenin in these samples. Feeding behaviour of adult Colorado potato beetles was not affected by the different food plants; this indicates that transgenic potato plants were readily accepted as host plants by beetles. The effects of these findings on the use of transgenic plants as a means of L. decemlineata control are discussed.

The present study tested the hypothesis that around the age of weaning, human infants are more interactive with their environment immediately after breastfeeding. To this aim, we assessed 4- to 6-month-old infants' responsiveness to a rotating, musical mobile before breastfeeding on one test day, and after breastfeeding on another. Thirteen infants, fitted with miniature movement detectors on both their left leg and wrist, were videotaped for 4 consecutive min during which the mobile was alternately switched on and off in 1-min intervals. Although the infants showed no significant differences in limb activity as a function of the timing of a breastfeed, they looked at the mobile significantly longer when tested after breastfeeding. This finding suggests that breastfeeding has a substantial effect on 4- to 6-month-old infants' attentiveness to and interaction with their environment. © 2000 John Wiley & Sons, Inc. Dev Psychobiol 36: 40–48, 2000

The present series of studies aimed to investigate whether experience with a flavor in mothers' milk modifies the infants' acceptance of similarly flavored foods at weaning. First, we established, using methods developed in our laboratory, that the ingestion of carrot juice by lactating women produced a sensory change in their milk approximately 2 to 3 hr after the ingestion of the beverage. Second, we randomly formed two groups of breast-fed infants who had been fed cereal for a few weeks but had only experienced cereal prepared with water. Their mothers were asked to consume one of two types of beverages (i.e., carrot juice, water) during the exposure period. Each mother was observed feeding her infant cereal during four test sessions. The first two sessions occurred during the 2 days before the exposure period; in counterbalanced order, infants were fed cereal prepared with water on 1 testing day and cereal prepared with carrot juice on the other. These two test sessions were then repeated following the exposure period. The results demonstrated that the infants who had exposure to the flavor of carrots in their mothers' milk during the exposure period consumed less of the carrot-flavored cereal and spent less time feeding when compared to the control infants whose mothers consumed the water. This may be a form of sensory-specific satiety such that the infants become less responsive to a flavor that they have been extensively exposed to in the very recent past.

Previous research demonstrated that breast-feeding infants consumed significantly less milk during the immediate hours after their mothers consumed an acute dose of alcohol when compared with a nonalcoholic beverage. The present study tested the hypothesis that maternal alcohol consumption decreases the amount of milk available to the infant and alters milk composition in the short term. To this aim, 22 lactating women were tested on 2 days separated by 1 week; the women reported that they drank very little during pregnancy, but significantly increased alcohol intake during lactation. Each woman drank a 0.3 g/kg dose of alcohol in orange juice on one testing day and orange juice alone on the other; the order was counterbalanced. Immediately before drinking the beverage (baseline) and 2 hr after (postconsumption), women expressed their milk by using an electric breast pump until no milk had been secreted from either breast for 5 min. Although there was no difference in the energy content of the milk, maternal alcohol consumption slightly, but significantly, reduced the amount of milk produced by the lactating mother. These findings underscore the importance of determining whether and when infants compensate for the reductions in intake experienced at the breast following maternal alcohol consumption and how such changes impact on mother-infant interaction.

Contrary to medical folklore, previous research has demonstrated that alcohol consumption by lactating women diminished milk intake by their infants during breast feeding. To determine whether this decrease in milk consumption was due to the infants responding to the altered flavor of the milk that also resulted, we evaluated the infants' intake and sucking responses to alcohol-flavored human milk outside of the context of breast feeding, thereby separating the changes due to the infants response to the flavor from any other changes that could also result from acute maternal alcohol consumption such as alterations in milk ejection or the composition of milk. The testing procedure consisted of a two-bottle preference test that was composed of four, 60-sec trials in which the mother's milk flavored with alcohol was alternated with the mother's milk alone in an ABBA or BAAB design. Attached to the nipple of each bottle was a transducer that responded to pressure changes produced by the infants' suckling. There was no suppression of sucking or intake in response to the ethanol-flavored milk. Rather, the infants consumed significantly more and sucked more frequently when drinking the alcohol-flavored milk compared with the unaltered milk. That experience with the flavor of alcohol in mothers' milk modified the infants' responses to alcohol flavor is suggested by the relationship between the reported frequency of mothers' drinking during lactation and the infants' rhythm and frequency of sucking when feeding the alcohol-flavored milk. These findings indicate that infants can readily detect the flavor of alcohol in mother's milk but that the decrease in consumption at the breast after maternal alcohol consumption is apparently not due to the infants rejecting the flavor of alcohol in their mothers' milk.

A radical change. ? irradiation of a DOPC (cis lipid) vesicle suspension containing RNase A shows protein degradation with formation of DEPC (trans lipid). Thiyl radicals are the isomerizing agents, deriving from the degradation of methionine residues, which are formed in the water compartment and diffuse in the lipid bilayer, converting the as fatty acid residues to the trans isomers.

After listening to an audio-recorded conversation between a man and a woman, student-judges rated the number of interruptions and relative amount of talk initiated by each speaker. Different versions of this scripted conversation, which was recorded by two teams of actors, varied: (1) the presence or absence of simultaneous speech, (2) the gender of the speaker initiating simultaneous speech, and (3) the affective context of the conversation. Both men and women judges significantly overestimated the talkativeness of a woman who interrupted a man in an otherwise cooperative conversation. The findings indicate that commonsense conceptions of interruption correspond to those of conversation analysts, and suggest that women's interruptions of men are perceived as particularly intrusive violations of conversational rights.

Two studies investigated the human infant's response to salt during development. In the first study, measures of intake and sucking were obtained from two groups of infants, newborns and 4- to 8-month-olds, in response to brief presentations of two concentrations of salt (0.2 or 0.4 M) and water. For several measures of sucking and for intake, there were significant age and concentration effects. Generally, newborn infants tended to reject saline relative to water more than did 4- to 8-month-old infants. This result, consistent with previously published research, suggests a developmental change in salt acceptability and, probably, sensitivity in the human infant. In the second longitudinal study, the response to salted (0.15 M) versus unsalted formulas was evaluated monthly in infants 2 to 7 months of age. Again, a developmental change was observed: Based on some sucking measures, younger infants appeared to be indifferent to the salted formula relative to the unsalted formula whereas older infants tended to reject the salted formula, presumably because either it was less sweet than the unsalted formulas or because it was novel. These data are consistent with the hypothesis developed from animal model studies that during early human postnatal development, transductive elements sensitive to saltiness mature.