Prevalence of hypertension and association of dietary mineral intake with blood pressure in healthy schoolchildren from northern Greece aged 7-15 years.

BACKGROUND AND AIMS: Pediatric hypertension is urgently increasing in Greece. The purpose of this study is to record the prevalence of hypertension in schoolchildren and to relate dietary minerals to blood pressure (BP). METHODS AND RESULTS: 308 males and 298 females, aged 7-15 years, from 10 schools in Northern Greece participated in the study. BP and dietary minerals were measured in all children. Twenty-seven and 12.3% of boys and 21.2 and 15.1% of girls were diagnosed with prehypertension systolic BP and systolic hypertension, respectively. For diastolic BP, 19 and 13.3% of boys and 21.5 and 15.1% of girls were diagnosed with prehypertension diastolic BP and diastolic hypertension, respectively. Systolic BP was significantly positively associated with age (beta: 0.283, 95% CI: 1.440-2.484, p < 0.001), BMI (beta: 0.267, 95% CI: 0.830-1.489, p < 0.001) and potassium (beta: 0.139, 95% CI: 0.001-0.005, p < 0.001) and negatively related to Ca (beta: -0.160, 95% CI: -0.012 to 0.002, p = 0.007). Diastolic BP was positively related only to BMI (beta: 0.194, 95% CI: 0.380-0.968, p < 0.001). CONCLUSION: The current study tried to estimate the prevalence of hypertension among children in Northern Greece. Early prevention through nutrition education programs on BP that include diet and exercise modifications is urgently needed in order to avoid certain chronic risk factors in early life.

Association of blood pressure, obesity and serum homocysteine levels in healthy children.

AIM: Obesity, hypertension and total serum homocysteine levels are well-known risk factors for cardiovascular disease in adults. However, there is limited data on the relation of these risk factors in children. METHODS: Five hundred twenty-four healthy school children aged 6-15 years participated in the study. BMI were used to categorize our subjects in normal overweight and obese groups based on Internationally Obesity Task Force criteria. RESULTS: The prevalence of overweight and obesity was 21.1% and 8.4% for boys and 17.6% and 7.3% for girls, respectively. Diastolic blood pressure (DBP), systolic blood pressure (SBP) and waist circumference (WC) were significantly higher in overweight and obese group compared to normal ones, whereas for homocysteine levels no difference was observed. Based on the results derived from the multiple regression analysis, BMI was positively related to energy intake (beta=0.247, p<0.001) and WC (beta=0.014, p<0.001). Both SBP and DBP were positively related to age ([beta=0.251, p<0.001] and [beta=0.301, p<0.001, respectively]), and BMI ([beta=0.096, p<0.001] and [beta=0.022, p<0.001], respectively). CONCLUSION: The current study revealed an association of blood pressure and WC with overweight and obesity in children, and even though these children may not have increased homocysteine levels, they still have enough reasons to reduce weight in order to avoid cardiovascular disease in their life later on.

Reference range of total serum homocysteine level and dietary indexes in healthy Greek schoolchildren aged 6-15 years.

Elevated total serum homocysteine (tHcy) may be a possible risk factor for CVD. A 5 micromol/l increase in tHcy is associated with an approximately 70 % increase in relative risk of CVD in adults. Data for children and adolescents are, however, limited. The purpose of the present study was to provide a reference range for tHcy and investigate any relationship between tHcy and nutritional indexes in a Greek paediatric population. tHcy, folate, vitamin B12 levels and dietary indexes were measured in 520 healthy schoolchildren (274 boys, 246 girls) aged 6-15 years. As in adults, the tHcy distribution skewed to the right, with a geometric mean for both genders of 7.4 (range 3.4-29 micromol/l). Concentrations were lower in young children and increased with age. No statistically significant difference in tHcy level was observed between gender. The 95th percentiles for the three age groups were as follows: 6-9 years, 9.98 micromol/l; 10-12 years, 10.62 micromol/l; 13-15 years, 14.4 micromol/l. Using Pearson's coefficient analysis, tHcy level was correlated with age, serum folate, BMI and systolic blood pressure. Dietary analysis showed that folate, vitamin B12 and fibre intake were inversely related with tHcy; conversely, sugar and fat were positively associated with tHcy. However, in multiple linear regression analysis, only age (odds ratio 0.246, P < 0.05) and folate (odds ratio -0.346, P < 0.05) were significantly and independently associated with tHcy. This study provides age-specific reference data regarding tHcy concentration in a Greek paediatric population. tHcy levels increased as a function of age. Serum folate levels were significantly and independently associated with tHcy levels.

The ketogenic diet in children with epilepsy.

Children with epilepsy, especially those facing intractable seizures, experience a great impact on the quality of their lives. Effective treatment is essential, and although new anti-epileptic drugs have shown an improved profile of action, still a substantial number of children look for more efficacious ways of treatment that are far away from potential toxicity and ineffectiveness. The ketogenic diet is a dietary therapy for epileptic children based on manipulation of metabolism principles and brain energetics. This regimen aims to produce a controlled ketonaemia through excessive dietary fat intake, little carbohydrates and adequate (for growth) protein. The present paper is a review of previous and current papers regarding the proposed mechanisms of the ketogenic diet's action, and the efficacy of the regimen on epileptic children. Unfortunately, a few small studies in sample size and duration tried to evaluate the potential risks of this regimen and their results were rather inconclusive. Further research needs to be done in order for the exact mechanism of the ketogenic diet to be clarified which will help to improve the diet's application, especially for vulnerable epileptic children as far as their growth is concerned.

Bioefficacy of L-lysine sulfate compared with feed-grade L-lysine-HCl in young pigs.

A pig growth assay was conducted to determine the relative biological value (RBV) of lysine from L-lysine sulfate compared with feed-grade L-lysine HCl. One hundred nursery pigs with an average initial BW of 9.5 +/- 1.5 kg were blocked by BW and gender and allotted randomly to five dietary treatments in five replicates of four pigs per pen. A corn-peanut meal diet containing 0.6% total lysine (as-fed basis) was supplemented with two levels (0.1 and 0.2%) of lysine from L-lysine-HCl or L-lysine sulfate. The RBV of L-lysine sulfate was determined using multiple regression slope-ratio methodology, with ADG and G:F as the response criteria. At the tested levels, linear responses for gain and G:F were obtained from increments of lysine from the two lysine sources. When ADG was regressed on supplemental lysine intake, the RBV of lysine in L-lysine sulfate was 99% of the RBV of lysine in L-lysine HCl. When G:F was regressed on supplemental lysine intake, the RBV of lysine in L-lysine sulfate was 97% of the RBV of lysine in L-lysine-HCl. The t-test analysis revealed that the RBV of lysine in L-lysine sulfate was not significantly different from the RBV of lysine in L-lysine HCl, which was assumed to be 100% bioavailable. In conclusion, L-lysine sulfate can replace L-lysine HCl in diets for growing swine.

Growth performance of different breed crosses of chicks fed diets with different protein and energy sources.

Six experiments (EXP) were conducted to evaluate growth performance of different breed crosses of broiler chicks fed diets containing soybean meal, soy protein isolate (SPI), soy protein concentrate (SPC), or rice and casein. Cornish x Plymouth Rock (C x PR; EXP 1, 3, 4, 5, and 6) or New Hampshire x Columbian (NH x C; EXP 2 and 4) cross chicks were used. The chicks were fed a corn-soybean meal (C-SBM) diet before allotment to treatment. The age of the chicks ranged from 5 to 9 d posthatching at the start of the EXP, and the assay periods ranged from 8 to 14 d. Initial weights were 194.9, 96.1, 102.1, 84.7 [84.1 (C x PR) or 85.3 (NH x C)], 101.8, and 145.1 g in EXP 1 to 6, respectively. A completely randomized design was used in all EXP, and treatments were replicated four to six times with four or five chicks each. All diets were formulated to meet the NRC nutrient requirements of chicks. In EXP 1 (C x PR male chicks) and EXP 2 (NH x C female chicks), gain and gain:feed (G:F) were greater (P < 0.01) in chicks fed the C-SBM diet compared with chicks fed diets containing SPI. In EXP 3, C x PR chicks were fed a C-SBM diet, a SPI-dextrose-cornstarch diet (dextrose:cornstarch, 1:1) formulated by Louisiana State University Agricultural Center (LSU) or a similar SPI diet (dextrose:cornstarch, 0.53:1) formulated by the University of Illinois (UI). Daily gain, average daily feed intake (ADFI), and G:F were increased (P < 0.01) in chicks fed the C-SBM diet relative to chicks fed the two SPI diets, and there were only minor differences between the two SPI diets. In EXP 4, the C x PR and NH x C male chicks were fed the same diets used in EXP 3. Daily gain and ADFI were greater in the C x PR and NH x C chicks fed the C-SBM diet relative to chicks fed the SPI diets (P < 0.01), but the increased average daily gain (ADG) and ADFI in chicks fed the C-SBM diet were much greater in the C x PR chicks (chick x C-SBM vs. SPI, P < 0.01). Daily gain, ADFI, and G:F were greater (P < 0.01) in C x PR chicks than in NH x C chicks. In EXP 5, ADG, ADFI, and G:F were greater (P < 0.04) in chicks fed the C-SBM diet compared with those fed a C-SPC diet. In EXP 6, C x PR chicks fed the C-SBM diet grew faster (P < 0.09) than those fed a rice and casein diet. Variable effects of diet on growth of chicks were affected by breed crosses of chicks.

Valine requirement of nursery pigs.

Six experiments were conducted to determine the true digestible valine requirement of 5- to 20-kg pigs. In Exp. 1, a valine-deficient diet for 5- to 10-kg pigs was developed and validated in terms of growth performance in response to supplemental L-valine. A different basal diet was validated for 10- to 20-kg pigs in Exp. 2. Both diets were demonstrated to be deficient in valine and to support performance equivalent to typical nursery diets when fortified with L-valine. In Exp. 3, true ileal digestibility of valine in the two basal diets was determined in eight pigs fitted with a simple T-cannula at the terminal ileum. Another four pigs received an enzymatically hydrolyzed casein-based diet to determine endogenous contributions to collected ileal digesta. The two diets were found to have true valine digestibilities of 82% (5- to 10-kg pigs) and 86% (10- to 20-kg pigs). In Exp. 4, 80 weaned pigs (5.8 kg) were offered the basal diet fortified with five incremental doses (0.08%) of L-valine. Weight gain increased quadratically (P < 0.05) with increasing levels of valine. Broken-line analysis revealed a true digestible valine requirement of 0.86 +/- 0.03%. In Exp. 5, the true digestible valine requirement of 10- to 20-kg pigs was estimated with 120 pigs (10.9 kg) using the second basal diet fortified with six incremental doses (0.05%) of L-valine. The data suggested a digestible valine requirement level of about 0.775%, which was reevaluated in Exp. 6, wherein pigs did not respond to levels of digestible valine higher than 0.775%. In conclusion, requirement estimates were 2.50 and 2.22 g of true digestible valine per megacalorie of ME for 5- to 10- and 10- to 20-kg pigs, respectively. These empirical estimates are in close agreement with recent estimates of the National Research Council Subcommittee on Swine Nutrition of 2.48 and 2.11 g of true digestible valine per megacalorie of ME, respectively.

True ileal digestibility of amino acids in sow's milk for 17-day-old pigs.

The digestibility of amino acids in sow's milk consumed by young pigs is currently unknown because of difficulties associated with collecting an adequate quantity of milk, and also problems in cannulating suckling pigs. A total of 14 kg of sow's milk was collected, two soluble indigestible markers (Co-EDTA and YbC13) were added, and the milk was fed to four pigs at 17 d of age that were fitted with a simple T-cannula at the terminal ileum. Another four cannulated pigs were offered a similar amount of a 20% DM liquid diet based on enzymatically hydrolyzed casein and lactose to assess endogenous amino acid losses. All pigs were fed about 875 g of each diet per day in 10 hourly meals from 0700 to 1700. Following 2 d of adaptation, ileal digesta were collected from 0800 to 1800 for 2 d. Diets and digesta were analyzed for amino acids using appropriate hydrolysis and preoxidation procedures. Average nitrogen true digestibility was 88%, whereas amino acid true digestibilities ranged from 84% (cystine and threonine) to 100% (methionine, histidine, and glutamic acid); the average for all amino acids was 92 +/- 4%. Based on average values, true digestibility of essential amino acids was not different from that of nonessential amino acids (P > 0.10). In whole milk, amino acids found in abundance in whey proteins (i.e., cystine, glycine, and threonine) were less (P < 0.05) digestible than amino acids predominating in casein proteins (i.e., glutamic acid, proline, and methionine). When true ileal digestible amino acid concentrations in sow's milk were expressed as ratios to digestible lysine, it appeared that threonine, tryptophan, and arginine were lower than what might be considered optimal. In conclusion, amino acids in sow's milk were highly digestible, but most of the amino acids had true ileal digestibility values significantly less than 100%.

Growth-promoting efficacy in young pigs of two sources of zinc oxide having either a high or a low bioavailability of zinc.

Commercial sources of zinc oxide (ZnO) differ widely in Zn relative bioavailability (RBV), but it is unknown whether growth-promoting efficacy in young pigs is influenced by RBV of the ZnO sources used. We compared a low-RBV (39%) ZnO manufactured by the Waelz process (W) to a high-RBV (93%) ZnO manufactured by the hydrosulfide process (HS). Antibacterial agents were included in the diet in only one of the four trials (Exp. 4). In Exp. 1, pigs (n = 36, 6.5 kg, 28 d of age) were randomly assigned in three replicates to receive 0, 1,500, or 3,000 mg Zn/kg from HS Zn in a 21-d growth assay. Growth rates and feed intake responded linearly (P < 0.01) to incremental doses of Zn. In Exp. 2, pigs (n = 60, 6.1 kg, 28 d of age) were randomly assigned in five replicates to receive either 0 or 1,500 mg W or HS Zn/kg during a 21-d feeding period. Growth performance was improved (P < 0.01) by the addition of ZnO. During wk 1, however, pigs receiving HS Zn grew faster (P < 0.03) than those receiving W Zn, but the difference diminished to a trend (P < 0.08) during wk 2. Morphology of duodenal, jejunal, and ileal intestinal sections was examined at d 21 of the assay, but neither source of ZnO had an effect on crypt depth or on villus height or width. In Exp. 3, weaned pigs (n = 48, 5.4 kg, 21 d of age) were randomly assigned in four replicates to the same dietary treatments as in Exp. 2 for a 17-d growth assay. Growth performance was improved (P < 0.05) by the addition of ZnO, but no difference was detected between the two sources. In Exp. 4, pigs (n = 60, 6.2 kg, 28 d of age) were randomly assigned in five replicates to receive either 0 or 1,500 mg/kg W or HS Zn in an 11-d growth assay wherein antimicrobial agents were included in the basal diet. Growth rates during the first 6-d were improved (P < 0.06) by the addition of ZnO, with a trend (P < 0.10) for greater weight gain in pigs receiving HS than in those fed W Zn. During the entire 11-d, however, there was no difference in growth rates between pigs fed the two sources of ZnO. In conclusion, RBV of Zn in ZnO did not substantially affect the growth-promoting efficacy of ZnO in young pigs fed diets with or without antimicrobial agents.

The effects of citric acid on phytate-phosphorus utilization in young chicks and pigs.

Several bioassays were conducted with young chicks and pigs fed phosphorus (P)-deficient corn-soybean meal diets. With diets for chicks containing .62% Ca and .42% P (.10% available P), graded doses of a citric acid + sodium citrate (1:1, wt:wt) mixture (0, 1, 2, 4, or 6% of diet) resulted in linear (P < .01) increases in both weight gain and tibia ash. Relative to chicks fed no citric acid, tibia ash (%) and weight gain (g/d) were increased by 43 and 22%, respectively, in chicks fed 6% citric acid. Additional chick trials showed that 6% citric acid alone or sodium citrate alone was as efficacious as the citric acid + sodium citrate mixture and that 1,450 U/kg of phytase produced a positive response in bone ash and weight gain in chicks fed a diet containing 6% citrate. Varying the Ca:available P ratio with and without citrate supplementation indicated that citric acid primarily affected phytate-P utilization, not Ca, in chicks. Moreover, chicks did not respond to citrate supplementation when fed a P-deficient (.13% available P), phytate-free casein-dextrose diet. Young pigs averaging 10 to 11 kg also were used to evaluate citric acid efficacy in two experiments. A P-deficient corn-soybean meal basal diet was used to construct five treatment diets that contained 1) no additive, 2) 3% citric acid, 3) 6% citric acid, 4) 1,450 U/kg phytase, and 5) 6% citric acid + 1,450 U/kg phytase. Phytase supplementation increased (P < .01) weight gain, gain:feed, and metatarsal ash, whereas citric acid addition increased only gain:feed (P < .05) and metatarsal ash (P < .08). A subsequent 22-d pig experiment was conducted to evaluate the effect of lower levels of citric acid (0, 1, 2, or 3%) or 1,450 U/kg phytase addition to a P-deficient corn-soybean meal diet. Phytase supplementation improved (P < .01) all criteria measured. Weight gain and gain:feed data suggested a response to citric acid addition, but this was not supported by fibula ash results (P > .10). The positive responses to phytase were much greater than those to citric acid in both pig experiments. Thus, dietary citric acid effectively improved phytate P utilization in chicks but had a much smaller effect in pigs.

Effects of pelleting and storage of a complex nursery pig diet on lysine bioavailability.

The effects of pelleting and storage of a complex nursery pig diet (28% lactose and 1.4% lysine) on lysine bioavailability were assessed in a chick bioassay. The nursery diet was steam-conditioned at 60 degrees C for 45 s and then pelleted through a 5-mm die with a depth of 38 mm. Samples of meal and pelleted diet were placed in metallic feeders in an occupied nursery facility for 1 wk (warm) or were stored at 4 degrees C (cool). For the standard-curve bioassay, a total of 144 8-d-old chicks were offered the following dietary treatments: 1 to 3) a basal diet (lysine deficient) and two levels (.08 and .16%) of added lysine (from L-lysine-HCl); 4 and 5) two positive controls (.7% added lysine with or without 10% of the nursery diet); and 6 to 9) basal diet plus 10% of one of the four nursery diet samples (meal or pellet stored cool or warm for 1 wk). Pelleting had no effect (P>.10) on lysine bioavailability, probably because pelleting conditions (temperature, humidity, and pellet size) were not aggressive enough to result in detectable effects on lysine utilization. However, storage in the nursery facility for 1 wk reduced (P<.03) lysine bioavailability by an average of 10%. No significant (P>.10) interactions were observed. Furthermore, true digestibility of lysine in the four pig diet samples was estimated in a cecectomized cockerel digestibility assay using 15 adult Single-Comb White Leghorn cockerels. Lysine digestibility in all samples was high (average of 94%) and was not affected (P>.10) by treatment. We conclude that the pelleting conditions used in our experiments did not decrease lysine utilization. More research is needed to define thermal processing conditions that might cause protein quality deterioration. However, typical warm and humid environmental conditions encountered in modern nursery facilities have a negative effect on protein quality of diets rich in reducing sugars and lysine.

Enzyme supplementation and particle size of wheat in diets for nursery and finishing pigs.

Three experiments were conducted to determine the effects of enzyme supplementation and particle size of wheat-based diets on growth performance and nutrient digestibility in nursery and finishing pigs. In Exp. 1, 180 weaned pigs (5.7 kg and 21 d of age) were fed diets in a 35-d growth assay without or with a Trichoderma longibrachiatium enzyme product (4,000 units of xylanase activity per gram of product) and with wheat ground to mean particle sizes of 1,300, 600, or 400 microm. Enzyme supplementation had no effect on ADG or gain/feed (P > 0.32), but there was a trend (P < 0.10) for greater digestibility of DM (d 6) in enzyme-supplemented diets. A particle size of 600 microm supported the greatest overall gain/feed (quadratic effect, P < 0.01). An interaction of enzyme supplementation with particle size occurred; gain/feed was improved (P < 0.01) with enzyme supplementation at the coarse (1,300 microm) particle size but not when the wheat was ground to 600 or 400 microm. In Exp. 2, 160 finishing pigs (67 kg) were fed a diet without or with the same enzyme used in Exp. 1 and wheat ground to 1,300 or 600 microm. No interactions occurred between enzyme supplementation and particle size of the wheat (P > 0.15). However, there were trends for greater gain/feed (P < 0.10) during the 67- to 93-kg phase of the experiment and for greater digestibility of DM (P < 0.10) and N (P < 0.07) with enzyme supplementation. When particle size was reduced from 1,300 to 600 microm, gain/feed was improved (P < 0.03) for the 93- to 114-kg phase of the growth assay, and digestibilities of DM (P < 0.02) and N (P < 0.04) were greater. In Exp. 3, 160 finishing pigs (63 kg) were given diets without or with the enzyme product and wheat ground to 600 or 400 microm. Enzyme supplementation improved ADG (P < 0.04) in the 90- to 115-kg phase but otherwise did not affect growth performance, carcass measurements, or stomach lesions. A particle size of 400 microm increased overall gain/feed (P < 0.04), digestibilities of DM and N (P < 0.01), and development of stomach lesions (P < 0.01). In conclusion, pigs did not benefit consistently from enzyme supplementation. However, wheat particle sizes of 600 and 400 microm supported the best overall performance in nursery and finishing pigs, respectively.

Single versus multiple deficiencies of methionine, zinc, riboflavin, vitamin B-6 and choline elicit surprising growth responses in young chicks.

A soy-protein isolate diet that was deficient in methionine (Met), zinc (Zn), riboflavin, vitamin B-6 and choline for chick growth (Assay 1) was used to study individual or multiple deficiencies of several of these nutrients. In all cases, adding all three deficient nutrients together resulted in growth responses that were superior to those resulting from supplementation with any pairs of deficient nutrients. In Assay 2, single addition of Zn but not of methionine or riboflavin produced a growth response, but the combination of either Zn and Met or Zn and riboflavin resulted in growth responses that were greater than the response elicited by Zn alone. Assay 3 involved individual or multiple deficiencies of choline, riboflavin and vitamin B-6, and individual additions suggested that choline was first limiting. Choline + riboflavin supplementation, however, produced marked growth and gain:food responses that were far greater than those resulting from supplemental choline or riboflavin alone. Moreover, the growth response to a combination of choline + pyridoxine (PN) was also greater than that obtained from any of the three nutrients fed alone; even PN + riboflavin (in the absence of choline) produced responses greater than those observed with the unsupplemented negative-control diet. In Assay 4, chicks responded to individual additions of riboflavin, PN or Met, and in Assay 5, to either riboflavin or PN; all two-way combinations resulted in growth rates that were far greater than those occurring with any single addition. The data from these experiments show that unlike the situation with three deficient amino acids, the expected responses to first-, second- and third-limiting B-vitamins or deficient vitamins combined with deficient levels of Zn or Met do not follow the expected pattern of response to first-, further response to first- and second- and an even further response to first-, second- and third-limiting nutrients.

Effects of omitting vitamin and trace mineral premixes and(or) reducing inorganic phosphorus additions on growth performance, carcass characteristics, and muscle quality in finishing pigs.

Three experiments were conducted to determine the effects of omitting vitamin and trace mineral premixes and(or) reducing inorganic phosphorus additions to finishing diets on growth performance, carcass characteristics, and muscle quality in pigs. In Exp. 1, a corn-soybean meal-based diet (.70% lysine, .65% Ca, and .55% P) was used as the control. Pigs (n = 128; average initial BW of 85.7 kg) were fed the control diet or the control diet without 1) the vitamin premix, 2) the trace mineral premix, or 3) both premixes. Omitting the premixes had no effect on ADG (P>.39); gain/feed (P>.17); carcass backfat thickness (P>.42); and marbling, color, and firmness of the longissimus muscle (P>.11). In Exp. 2, pigs (n = 128; average initial BW of 86.2 kg) were fed the control diet (.65% Ca and .53% P) used in Exp. 1 and the control diet without 1/3 (.56% Ca and .46% P), 2/3 (.51% Ca and .40% P), or all (.47% Ca and .31% P) of the added monocalcium phosphate (MCP). Omitting up to 2/3 of the MCP increased ADG (quadratic effect, P<.02) and had no effect on meat quality (P>.12), but backfat thickness increased slightly (quadratic effect, P<.02). In Exp. 3, pigs (n = 160; average initial BW of 86.6 kg) were fed the control diet used in Exp. 1 or the control without 1) the vitamin and trace mineral premixes, 2) 2/3 of the MCP, or 3) the premixes and 2/3 of the MCP. Treatment had no effects on ADG (P>.23), gain/feed (P>.94), stomach lesions (P>.37), or serum gamma globulins (P>.08). In conclusion, vitamin and trace mineral premixes and up to 2/3 of the supplemental MCP can be omitted during late finishing (i.e., approximately the final 30 d) to reduce nutrient excesses that increase cost of feeding and nutrients excreted in waste material.

Prevalence of migraine in schoolchildren and some clinical comparisons between migraine with and without aura.

OBJECTIVES: To determine the prevalence of migraine and its association with age, gender, and social class and to find out whether or not the headache and nonheadache characteristics differ between children with migraine, with and without aura, using the diagnostic criteria of the International Headache Society for childhood migraine. DESIGN: Population-based study in two stages comprising an initial screening questionnaire followed by telephone interviews of children with symptoms. SETTING: Eighteen kindergarten and 39 primary and secondary schools in Thessaloniki and its semiurban areas. SUBJECTS: Four thousand children, aged 4 to 15 years, representing a random sample of 5% of schoolchildren in Thessaloniki and its semiurban areas. MAIN OUTCOME MEASURES: (1) The prevalence of migraine, (2) the connection of migraine with social class, (3) differences in the occurrence of individual symptoms between migraine with and without aura. RESULTS: The results of the present study show that migraine prevalence was 6.2% (95% confidence interval [CI], 5.4 to 7.0). The estimated prevalences of migraine with and without aura were 2.8% (95% CI, 2.3 to 3.4) and 3.4% (CI, 2.8 to 4.0), respectively. The prevalence of migraine increased with age and it was found to be almost equal in boys and girls aged 7 to 9 years or younger, but in older age groups the prevalence was higher in girls than in boys. The data showed no evidence that connected migraine with social class. It also showed that except for the aura, the headache (e.g., frequency, duration, location, quality, and severity) and nonheadache (e.g., nausea, vomiting, phonophobia, and photophobia) characteristics were no different between children with migraine, with and without aura. In conclusion, our findings indicate that migraine is a common underdiagnosed cause of severe recurrent headache in children. The findings show that childhood migraine is not connected with social class and varies with age and gender, and that except for the aura, both migraine with and without aura are so similar in their headache and nonheadache clinical characteristics that a common pathogenesis is plausible.

Limiting order of amino acids in a low-protein corn-soybean meal-whey-based diet for nursery pigs.

Three trials were carried out with pigs between 5 and 8 wk of age to determine the limiting order of amino acids in a 13.5% CP corn-soybean meal-based diet containing 8% dried whey. The positive-control diet was a 19.2% CP corn-soybean meal-based diet (1.15% lysine), also with 8% dried whey. Amino acid additions to the low-protein, negative-control diet were based on levels needed to accomplish 110% of ideal ratios (to lysine, set at 1.15%). In Exp. 1, the addition of an amino acid mixture containing Lys, Trp, Thr, Met, Ile, and Val to the low-protein diet increased (P<.05) gain and gain: feed ratio, and these response traits were not different from those of pigs fed the 19.2% CP positive-control diet. Single deletion of Lys from the supplemental amino acid mixture depressed performance to a greater (P<.05) extent than single deletion of any of the other amino acids. Single deletions of Trp, Thr, Met, or Val decreased (P<.05) performance in a similar but lesser magnitude than the decrease caused by Lys deletion, whereas Ile deletion was without effect. Experiments 2 and 3 were designed to evaluate the limiting order of AA beyond Lys in the low-protein diet. Neither His nor Glu were found to be deficient, and, as in Exp. 1, deletion of Trp, Thr, Met, or Val from the supplemental amino acid mixture resulted in performance depressions (P<.05) that were similar. The results suggest that Lys is first-limiting and Trp, Thr, Met, and Val are equally second-limiting in a reduced protein (13.5% CP) corn-soybean meal-based diet with 8% whey for 10-kg pigs.