The impact of rising sea temperatures on an Arctic top predator, the narwhal.

Arctic top predators are expected to be impacted by increasing temperatures associated with climate change, but the relationship between increasing sea temperatures and population dynamics of Arctic cetaceans remains largely unexplored. Narwhals (Monodon monoceros) are considered to be among the most sensitive of Arctic endemic marine mammals to climate change due to their limited prey selection, strict migratory patterns and high site fidelity. In the context of climate change, we assume that the population dynamics of narwhals are partly influenced by changes in environmental conditions, with warm areas of increasing sea temperatures having lower abundance of narwhals. Using a unique large dataset of 144 satellite tracked narwhals, sea surface temperature (SST) data spanning 25 years (1993-2018) and narwhal abundance estimates from 17 localities, we (1) assessed the thermal exposure of this species, (2) investigated the SST trends at the summer foraging grounds, and (3) assessed the relationship between SST and abundance of narwhals. We showed a sharp SST increase in Northwest, Mideast and Southeast Greenland, whereas no change could be detected in the Canadian Arctic Archipelago (CAA) and in the Greenland Sea. The rising sea temperatures were correlated with the smallest narwhal abundance observed in the Mideast and Southeast Greenland (< 2000 individuals), where the mean summer sea temperatures were the highest (6.3 °C) compared to the cold waters of the CAA (0.7 °C) that were associated with the largest narwhal populations (> 40,000 individuals). These results support the hypothesis that warming ocean waters will restrict the habitat range of the narwhal, further suggesting that narwhals from Mideast and Southeast Greenland may be under pressure to abandon their traditional habitats due to ocean warming, and consequently either migrate further North or locally go extinct.

Nutrition labels in bar graph format deemed most useful for consumer purchase decisions using adaptive conjoint analysis.

This study estimated the effects of changing multiple levels and combinations of nutrition information format, load, expression, and order on consumers' perceptions of label usefulness in purchase decisions using adaptive conjoint analysis. A shopping mall intercept survey, which was administered by a marketing research firm, assessed consumer preferences for 12 label alternatives produced on Campbell's soup cans to portray nutrition information realistically; 252 of 258 respondents completed the computer interactive interview. Consumers significantly preferred the bar graph format to the bar graph/nutrient density and traditional label formats. Consumers considered the bar graph/nutrient density format to be as useful as the traditional label format. There was a highly significant difference among the three levels of information load; the most information load was preferred regardless of nutrient importance. Consumers significantly preferred nutrition information stated in absolute numbers and percentages vs in absolute numbers only in traditional, or in percentages only expressions. There was a significant difference between consumer preferences for the two types of information order. The findings indicate that consumers clearly preferred the nutrition label that displayed all nutrient values using a bar graph format, offered the most information load, and expressed nutrient values using both absolute numbers and percentages. Consumers also preferred nutrition information rearranged in an order that grouped nutrients that should be consumed in adequate amounts on the top, calories in the middle, and nutrients that should be consumed in lesser amounts on the bottom of the label.

Review of nutrition labeling formats.

This article examines nutrition labeling history as well as the findings of nine research studies of nutrition labeling formats. Nutrition labeling regulations were announced in 1973 and have been periodically amended since then. In response to requests from consumers and health care professionals for revision of the labeling system, the Food and Drug Administration initiated a three-phase plan for reform of nutrition labeling in 1990. President Bush signed the Nutrition Labeling and Education Act in November 1990. Literature analysis revealed that only nine studies with an experimental design have focused on nutrition labeling since 1971. Four were conducted before 1975, which was the year that nutrition labeling was officially implemented, two were conducted in 1980, and three were conducted after 1986. Only two of the nine studies supported the traditional label format mandated by the Code of Federal Regulations, and one study partially supported it. Four of the nine studies that evaluated graphic presentations of nutrition information found that consumer comprehension of nutrition information was improved with a graphic format for nutrition labeling: three studies supported the use of bar graphs and one study supported the use of a pie chart. Full disclosure (ie, complete nutrient and ingredient labeling) was preferred by consumers in two of the three studies that examined this variable. The third study supported three types of information disclosure dependent upon socioeconomic class. In those studies that tested graphics, a bar graph format was significantly preferred and showed better consumer comprehension than the traditional format.

Mild pantothenate deficiency in rats elevates serum triglyceride and free fatty acid levels.

Pantothenate-derived coenzymes are extensively involved in intermediary metabolism, particularly in the metabolism of lipids. Using a rat model of diet-induced pantothenate deficiency, we hoped in this study to relate pantothenate status, as indicated by serum pantothenate and hepatic coenzyme A, to levels of circulating triglycerides and free fatty acids. Although commercial "vitamin-free" casein contained approximately 3 mg total pantothenate per kilogram, marked changes in serum pantothenate and hepatic CoA still occurred during weeks when rats were fed purified diets supplemented with 0 to 1600 mg pantothenate per kilogram of diet. Conditions in different experiments included ad libitum or pair-feeding of 3- or 6-wk-old rats and blood sampling from 3 to 24 h after feeding. Under most conditions of mild pantothenate deficiency in which weight differences between groups were not statistically significant, serum triglyceride and free fatty acid levels were significantly elevated in pantothenate-deficient groups. Mild pantothenate deficiency appears to have observable in vivo effects on triglyceride metabolism before severe deficiency causes significant weight loss.

Enzymes for liberation of pantothenic acid in blood: use of plasma pantetheinase.

Reported normal concentrations for human whole-blood total pantothenic acid vary from 1.1 to 12 mumol/L. This wide range may partly arise from the various enzymes used for liberation of pantothenic acid from coenzyme A, particularly the source of pantetheinase. A purified pantetheinase from pig kidney had greater than 100 times the specific activity and less than 0.01 times the pantothenate content of other commonly used extracts. Endogenous pantetheinase activity in human plasma was identified (11.2 +/- 2.0 mumol pantothenate .min-1.L-1, n = 29) and found comparable to the activity usually added from exogenous sources for liberation of pantothenate from whole blood (1-13 mumol.min-1.L-1). Alkaline phosphatase alone liberated as much pantothenate from hemolyzed whole blood as did alkaline phosphatase with pantetheinase. Previous reports of total blood pantothenate may be elevated by pantothenate in the pantetheinase extracts, an unnecessary source of error. Whole-blood total pantothenate concentrations less than 4.6 mumol/L are normal and do not indicate deficiency, as is often currently quoted.

Pantethine lipomodulation: evidence for cysteamine mediation in vitro and in vivo.

Recent human studies suggest rapid in vivo hydrolysis of the lipid-lowering drug, pantethine, to the vitamin pantothenic acid and the small aminothiol compound, cysteamine. To test whether the active agent is a hydrolysis product, we repeated three experimental models of pantethine's effect with pantothenate and cysteamine. In vitro experiments with human fetal fibroblasts showed equivalent modulation of cholesterol and methyl sterol synthesis by pantethine, cysteamine, or cystamine (the disulfide of cysteamine), but pantothenate had no effect. Similarly, in vivo experiments with 0.5% cholesterol-fed rabbits showed oral pantethine or equimolar cystamine significantly lowered plasma cholesterol, while pantothenate, cystine, and 2-hydroxyethyl disulfide did not. Lastly, diabetic male rats (40 mg/kg streptozotocin) fed 0.1% pantethine and lower plasma free fatty acids after 2 weeks than controls, an effect not seen with pantothenate and largely duplicated by cystamine. The efficacy of pantethine has previously been attributed to altered vitamin metabolism and increased coenzyme A concentration. Pantethine did increase CoA levels 45% in rat liver homogenates while equivalent amounts of cystamine or pantothenate did not. However, a causal relationship between CoA levels and pantethine's action as a hypolipemic agent has never been shown. At least in 3 independent experimental models, the lipomodulating effect of pantethine appears instead to be mediated by the hydrolysis product cysteamine.

Dissociation and diurnal variation of prostaglandin E2 6-keto-prostaglandin-F1-alpha, and thromboxane B2 excretion in healthy females.

The existence of diurnal variation in renal function is well described. Prostaglandins are intimately involved with renal physiology, yet a diurnal variation in their excretion is not well documented. We collected 12 consecutive 2 hour urine specimens from 10 young healthy females and measured prostaglandin E2 [PGE2], thromboxane B2 [TXB2], and 6-keto-prostaglandin-F1-alpha by radioimmunoassay for each specimen. We also measured urine volume, urine sodium, and urine creatinine levels. Regression analysis was used to determine the best sine curve for time versus each set of mean values. Only the urinary excretion of PGE2 and TXB2, as well as water were found to significantly fit the generated sine curves. The curves for PGE2 and TXB2 showed a temporal dissociation in their peak and trough values. The excretion of PGE2 between 0800 hours and 2000 hours was significantly higher than during the hours of 2000 and 0800. The opposite was true for the TXB2 excretion. This data suggests that these two prostaglandins and water are excreted in a sine wave pattern. It also suggests that the excretion of PGE2 and TXB2 may respond to different time associated stimuli. We also showed a significant correlation between PGE2 excretion and both the excretion of water and sodium.

Pantothenic acid status of adolescents.

Information on human needs for pantothenic acid is limited and no recommended daily allowance has been established, although a safe and adequate level of 4-7 mg/day has been suggested for adults and adolescents. Pantothenic acid levels in urine, whole blood, and erythrocytes were determined by radioimmunoassay in 63 healthy adolescents. Dietary intakes were calculated and evaluated from 4-day diet records. Although 49% of the females and 15% of the males consumed less than 4 mg/day, average blood levels for both groups were in a normal range relative to other populations (411.9 +/- 102.8 ng/mL and 344.5 +/- 113.6 ng/mL, respectively). Dietary intake was highly correlated with urinary excretion (p less than 0.001). Levels of pantothenic acid in erythrocytes correlated well with dietary intake and urinary excretion. A model was developed to predict circulating levels of pantothenic acid from dietary intake and urinary excretion.

Cluster analysis to improve food classification within commodity groups.

Mathematical clustering algorithms were used to classify foods within dairy, grain, and fat commodity groups on the basis of nutrients with limited availability in the food supply as well as those posing a possible health risk due to excess consumption. The procedure overcomes the problem that has made objective and accurate grouping, i.e., dealing simultaneously with 10 or more nutrients, difficult. The clustering routine classifies foods on the basis of similar nutrient content for any number of food attributes and assigns a degree of association to each food to indicate its compositional similarity to a prototype food for the cluster group. Foods within dairy, grain, and fat commodity groups were clustered on the basis of similar content of vitamin B-6, calcium, iron, magnesium, folacin, zinc, and added sugar, fat, cholesterol, and sodium. Whole milk and natural cheese clustered together on the basis of their moderate nutrient and relatively high fat and sodium content. Whole wheat breads, pumpernickel bread, and pancakes from mix constituted a grain subgroup with highest nutrient content, lowest cholesterol and sugar, lower fat, and higher sodium. Other subgroups based upon similarities in attributes were identified within food commodity categories. The result is an expansion of some food groups to incorporate concepts of both nutritional adequacy and moderation of food components of current nutritional concern.

Nutrition intervention: panacea or Pandora's box?

Past intervention efforts have not been effective in solving the nutrition problems in either industrialized or developing nations. While it may be intellectually stimulating, arguing over the subtleties of various strategies does not serve to improve the nutritional well-being of populations and may actually be detrimental. Whether we are concerned about an excess of calories or an inadequate supply of calories, the issue of calories is critical worldwide. A nutrient density approach provides a unified, scientifically justifiable, comprehensive approach to improving the nutritional status of populations in both developed and developing countries.

Pantothenic acid status of pregnant and lactating women.

Pantothenic acid nutritional status was evaluated longitudinally in 26 pregnant women (experimental group) during their third trimester of pregnancy and at 2 weeks and 3 months postpartum. Seventeen nonpregnant and nonlactating women (control group) participated at the same time intervals. All the women were assessed by the intake calculated from a reported 2-day dietary record and by fasted blood, plasma, and 24-hour urinary levels of pantothenate determined by a radioimmunoassay. Estimated daily mean dietary pantothenate intake and the vitamin density for the experimental group were not statistically different from those for the control group. The dietary pantothenate intake averaged 2.75 mg/1,000 kcal. Average pantothenate blood level of the experimental group was lower than that of the control group. No significant difference was found between the two groups in the pantothenate levels of fasting plasma and urinary excretion. When they did not take pantothenic acid supplements, members of the experimental group had intakes less than the Estimated Safe and Adequate Daily Dietary Intake and lower mean blood values than the members of the control group. This suggests that pregnant and lactating women need to consume more pantothenate to maintain a blood vitamin level similar to that of nonpregnant women. This may be achieved by an increased caloric intake, if desirable, or by more careful selection of foods high in the nutrient.

Effect of pantothenic acid status on the content of the vitamin in human milk.

Seventeen lactating women who delivered preterm infants (between 28 to 34 wk of gestational age) and 26 nursing mothers of term infants participated in the study. Each term mother kept a record of 2-day dietary intakes, collected urines for 2 days, and provided fore and hind milk samples and a fasting blood sample at 2 and 12 wk postpartum. Each of preterm women provided fore and hind milk samples once a week for 16 wk starting 2 wk postpartum. The method of determining pantothenic acid content in milk samples was validated, and the vitamin was quantitated by the radioimmunoassay. The average pantothenate levels in fore and hind samples of preterm milk (3.31 and 3.72 micrograms/ml, respectively) were significantly (p less than 0.05) higher than those of term milk (2.64 and 2.48 micrograms/ml, respectively). No significant change was observed in pantothenic acid content within a feeding or with the progress of nursing in both groups. The vitamin content of human milk was compared with the minimum requirement of the Infant Formula Act of 1980. The pantothenate level in term milk was significantly (p less than 0.05) correlated with the vitamin level in maternal circulation and with that of the dietary intake and urinary excretion.

Double balanced chromosomal translocation carrier (6;8), (13;14)--a case report.

This paper reports the identification of a carrier of two different balanced chromosomal translocations (45,XX,-13,-14, + t(13q;14q), t(6;8) (p11;p12]. Ascertainment occurred during family studies following prenatal diagnosis performed because of advanced maternal age. Family pedigree and past reproductive difficulties also are reviewed, and the theoretical probability of producing a phenotypically normal offspring is explored. We are unaware of previously published observations in which two different balanced autosomal translocations are found in the same individual.

Purification and properties of a pantetheine-hydrolyzing enzyme from pig kidney.

A microsomal glycoprotein that catalyzes the hydrolysis of pantetheine to pantothenate and cysteamine was solubilized and purified to homogeneity as determined by sodium dodecyl sulfate electrophoresis. The enzyme from pig kidney cortex was solubilized on exposure to butanol and purified by heat treatment, ammonium sulfate fractionation, hydrophobic chromatography, and hydroxyapatite chromatography. The purified enzyme (Mr = 57,000) has a specific activity of 14 mumol of pantothenate produced per min/mg of protein, a value 35 times that previously reported. A method for localizing enzymatic activity on polyacrylamide gels is presented, and enzyme activity, protein, and carbohydrate are shown to migrate identically by electrophoresis on nondenaturing polyacrylamide gels. Amino acid analysis indicated an absorbance index E1%1cm (280 nm) of 11.3, and carbohydrate analysis revealed the presence of galactose, mannose, fucose, glucose, galactosamine, and sialic acid for a total carbohydrate composition of 11.8%. The enzymatic hydrolysis of various pantetheine analogs indicated the enzyme had a high specificity for the pantothenate moiety but a low specificity for the cysteamine portion.

Alcohol consumption and nutrient density of diets in the Nationwide Food Consumption Survey.

Alcoholic beverage data from the U.S. Department of Agriculture's Nationwide Food Consumption Survey (NFCS), 1977-78, were compared with apparent consumption data from the U.S. Department of Health and Human Services (DHHS). NFCS data indicate that only one-fifth of the alcohol estimated to be consumed by DHHS is reported at the household level. For those individuals consuming alcoholic beverages, energy levels were higher than for non-drinkers. Average daily nutrient intake for most nutrients was similar for drinkers and non-drinkers. The nutrient density of diets of drinkers was significantly lower than that of non-drinkers with respect to protein, fat, carbohydrate, calcium, iron, phosphorus, vitamin A, and thiamin.