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The goal of this study was to determine the effects of short-term feed withdrawal on reproductive and metabolic hormones during the luteal phase of the estrous cycle in mature ewes. Mature ewes observed in estrus were assigned randomly to control and fasted groups (n = 10 per group Trials 1 and 2). For Trials 1 and 2, control ewes had ad libitum access to feed, whereas fasted ewes were not fed from d 7 through 11 of their estrous cycle; on d 12, all ewes were treated with 10 mg of PG[F.sub.2[alpha]] and fasted ewes were given ad libitum access to feed. For Trial 1, blood samples were collected daily through fasting and at 2-h intervals following PG[F.sub.2[alpha]] for 72 h. Serum concentrations of insulin (P [less than or equal to] 0.002) and IGF-I (P [less than or equal to] 0.01), but not GH (P [greater than or equal to] 0.60), were decreased during fasting compared with fed ewes. Serum concentrations of 29 (P = 0.02) and 34 kDa (P = 0.04) IGFBP were greater in fasted ewes at 96 h after initiation of fasting than in control ewes. Two control and four fasted ewes in Trial I did not exhibit a preovulatory surge release of LH by 72 h. Therefore, Trial 2 was conducted so that the timing of the LH surge could be predicted following the collection of blood samples at 2-h intervals for 112 h and then at 6-h intervals until 178 h following PG[F.sub.2[alpha]], administration and realimentation. The magnitude of the preovulatory LH surge in Trial 2 was decreased (P = 0.009) and delayed (P = 0.04), and serum concentrations of estradiol were diminished (P [less than or equal to] 0.03) 12 h before the LH surge in fasted ewes. Ovulation rates were not influenced (P [greater than or equal to] 0.32) by fasting in Trials 1 and 2. Serum concentrations of progesterone in both Trials 1 and 2 were, however, greater (P < 0.001) in fasted than in control ewes. A third trial with ovariectomized ewes was conducted to determine whether the increased serum concentrations of progesterone observed in fasted ewes during Trials 1 and 2 were ovarian-derived. Ovariectomized ewes were implanted with progesterone-containing intravaginal implants and allotted to control (n = 5) or fasted (n =5) treatment groups and fed as described for Trials 1 and 2. Similar to intact ewes, serum concentrations of progesterone were approximately twofold greater (P < 0.001) in fasted than in control implanted ovariectomized ewes. In summary, feed withdrawal for 5 d during the luteal phase of the estrous cycle increased serum concentrations of progesterone and evoked endocrine changes that could perturb the subsequent estrous cycle. Key Words: Fasting, Ovulation Rates, Reproductive Hormones, Sheep

Two trials were conducted to determine the effect of energy source (ENG) and ruminally degradable protein (RDP) on lactating cow performance and intake and digestion in beef steers. In Trial 1, 78 cow-calf pairs were used in a 2 z 2 factorial design to determine the effect of ENG (corn or soyhulls; SH) and RDP (with our without sunflower meal) to a forage diet for lactating beef cows. The basal diet consisted of 75% grass hay (11.5% CP) and 25% wheat straw (7.4% CP). Supplement treatments and predicted RDP balances were corn (-415 g of RDP/d); SH (-260 g of RDP/d); corn plus RDP (0 g of RDP/d); or SH plus RDP (0 g of RDP/d). Data were analyzed as a split-plot in time, with pen as the experimental unit (two pens per treatment). No interaction between ENG and RDP was present (P [greater than or equal to] 0.08) for any response variable. No differences (P [greater than or equal to] 0.39) due to ENG or RDP were noted for BW, BCS, or milk yield; however, final calf weight tended to increase with ENG (P = 0.06). In Trial 2, a 5 x 5 Latin square was used to determine effects of ENG and RDP on intake and digestion in steers (686 [+ or -] 51 kg BW). Treatments were arranged as a 2 x 2 plus one factorial and comprised a control (CON; grass hay, 7% CP), grass hay plus 0.4% BW SH, grass hay plus 0.4% BW SH and 0.15% BW sunflower meal, grass hay plus 0.4% BW corn, and grass hay plus 0.4% BW corn and 0.2% BW sunflower meal. Preplanned contrasts included main effects of ENG and RDP, ENG x RDP interaction, and CON vs. supplemented (SUP) treatments. Supplementation increased total DMI compared with CON (P = 0.001), but forage DMI was greater (P = 0.001) for CON than for SUP. An ENG x RDP interaction occurred for forage DMI (P = 0.02); addition of RDP to corn decreased forage intake, whereas addition of RDP to SH had no effect. There was an ENG x RDP interaction (P = 0.001) for ruminal pH; pH tended to increase with RDP addition to SH (P = 0.07), but decreased with RDP addition to corn (P = 0.001). Supplementation increased ruminal ammonia compared with CON (P = 0.001). Likewise, RDP increased ruminal ammonia (P = 0.001). An interaction occurred for OM disappearance (OMD; P = 0.01). The RDP addition to SH numerically decreased OMD (P = 0.23), whereas RDP addition to corn numerically increased OMD (P = 0.14). Intake and digestion seem to respond differently to RDP addition depending on supplemental energy source. Both corn or SH seem to be suitable supplements for the quality of forage used in this trial. Addition of supplemental protein did not improve cow or calf performance. Key Words: Corn, Cows, Digestion, Protein, Soyhulls, Steers

Sixteen castrated male pigs (averaging 21.2 [+ or -] 4.9 kg) were used in two trials to investigate the effect of dietary amino acid content during the grower phase on growth performance and N balance. In each trial, pigs were assigned randomly to corn-soybean meal grower diets formulated to contain 5.0 or 11.0 g lysine/kg (as-fed basis). Common Finisher 1 and 2 diets were offered when pigs reached 51.2 [+ or -] 3.3 and 79.5 [+ or -] 3.4 kg, respectively. Pigs were placed in metabolism crates for a 9-d period during each of the grower, Finisher 1, and Finisher 2 phases when they weighed 43.3 [+ or -] 3.9, 70.4 [+ or -] 4.9, and 90.5 [+ or -] 3.8 kg, respectively, to determine N balance. Blood samples were taken from each pig periodically after an overnight fast. Pigs were allowed ad libitum access to feed and water, except during the three adaptation/collection periods. There were no diet x trial interactions; thus, the data were combined. Pigs fed the low-amino acid grower diet grew more slowly and less efficiently (P < 0.001) during the grower phase and had more ultrasound backfat (P = 0.010) at the end of the grower phase than those fed the high-amino acid grower diet. During the Finisher 1 phase, however, pigs fed the low-amino acid diet grew more efficiently (P = 0.012) than those fed the high amino acid diet, and the grower diet had no effect on overall weight gain, carcass traits, lean accretion, or meat quality scores. Although pigs fed the low-amino acid diet had less serum urea N (P < 0.001) and more glucose (P = 0.009) at 43.3 kg, there seemed to be no clear, long-term effect of the grower diet on serum metabolites. During the grower phase, pigs fed the high-amino acid diet consumed more N (P < 0.001), had higher apparent N digestibility (P = 0.041), N utilization (P = 0.027), and N retention (P < 0.001), and excreted more fecal (P = 0.034) and urinary (P < 0.001) N than those fed the low-amino acid diet. Pigs fed the low-amino acid grower diet, however, had a higher N utilization (P = 0.024) during the Finisher 1 phase, and excreted less urinary N during both the Finisher 1 (P = 0.029) and 2 (P = 0.027) phases than those fed the high-amino acid grower diet. These results indicate that pigs subjected to early dietary amino acid restrictions compensated completely and decreased N excretion during both the restriction and realimentation phases. Compensatory growth can, therefore, have a positive effect not only on the overall efficiency of pig production but also on environment. Key Words: Compensatory Growth, Dietary Restrictions, Nitrogen Balance, Pigs

The hindlimb arteriovenous difference (AVD) model was used to determine whether 30 mg/ kg of the nitric oxide synthase (NOS) inhibitor L-[N.sup.G]-nitroarginine methyl ester (hydrochloride; L-NAME) inhibited ovine NO synthesis and influenced muscle metabolism. Eight Border Leicester x Merino cross lambs (50 to 55 kg BW) were infused with saline (control) or saline containing L-NAME via an indwelling jugular vein catheter in a balanced randomized crossover design with 3 d between treatments. The abdominal aorta and deep femoral vein were catheterized for assessment of AVD of hind limb metabolism. Arterial hematocrit and insulin concentration and both arterial and venous concentrations of nitrate/nitrite (N[O.sub.x]), glucose, lactate, NEFA, and urea were determined. Infusion of L-NAME decreased arterial N[O.sub.x] concentrations (P = 0.049), indicating inhibition of systemic NO synthesis. Treatment had no effect on arterial (3.5 vs. 3.6 [+ or -] 0.19 mmol/L for control and L-NAME lambs, respectively; P = 0.39) or venous (3.3 vs. 3.4 [+ or-] 0.16 mmol/L, P = 0.55) plasma glucose concentrations or on glucose AVD (0.19 vs. 0.27 [+ or -] 0.065 mmol/L, P = 0.20). There was an interaction (P = 0.038) between time and treatment, such that LNAME initially increased the AVD of glucose (up to 180 m) divergent from control lambs. The response was then decreased before a possible inflection beyond 240 min. Infusion of L-NAME increased hindlimb venous NEFA (222 vs. 272 [+ or-] 13.2 [micro]mol/L, P = 0.007) and NEFA AVD (79.4 vs. -13.3 [+ or -] 31.5 [micro]mol/L, P = 0.018). These metabolic changes were independent of plasma insulin concentrations, which were not affected by L-NAME infusion (25.3 vs. 27.8 [+ or -] 3.62 mU/L, P = 0.85). The increase in hindlimb lipolysis after L-NAME infusion does not seem to be due to increased lipolysis of plasma triacylglycerol because circulating arterial (155 vs. 142 [+ or -] 20.8 [micro]mol/L, P = 0.58), venous (154 vs. 140 [+ or -] 20.5 [micro]mol/L, P = 0.50), and AVD (1.0 vs. 2.9 [+ or -] 3.17 [micro]mol/L, P = 0.38) triacylglycerol concentrations were unaffected by L-NAME infusion. In conclusion, these data indicate that infusion of 30 mg of L-NAME/kg inhibits NO synthesis, which in turn influences fat and carbohydrate metabolism in the ovine hindlimb independently of plasma insulin concentrations. Key Words: Glucose, Insulin, L-[N.sub.G]-Nitroarginine Methyl Ester (Hydrochloride), Nitric Oxide, Nonesterified Fatty Acids, Ovine

Clinical trials have noted hypocholesterolemic effects of soy protein intake, but the components responsible are not known. This meta-analysis of 8 randomized controlled trials was conducted to more precisely evaluate the effects of isoflavones on blood LDL cholesterol concentration independently of soy protein level. PubMed was searched for English-language 'randomized controlled trial' articles published from 1966 to 2003 that described the effects of soy protein isolate (SPI) intake with measured isoflavone levels on blood lipids in humans using the search terms 'soy protein,' 'isoflavones,' and 'cholesterol.' From 31 articles identified by the search, 8 articles (with 10 low vs. high isoflavone comparisons) were selected for the meta-analysis. Subjects in each comparison consumed similar dietary fat, cholesterol, and fiber; the reported body weight of subjects did not change significantly during treatment. Serum LDL cholesterol concentration in subjects who consumed SPI (mean 50 g/d) with high isoflavone content (mean intake 96 mg/d) decreased by 0.15 mmol/L (95% CI: 0.08 to 0.23 mmol/L; P < 0.0001) compared with those who consumed the same SPI level with low isoflavone content (mean intake 6 mg/d). Decreases in serum LDL cholesterol concentration in hypercholesterolemic and normocholesterolemic subjects were 0.18 mmol/L (95% CI: 0.01 to 0.35 mmol/L; P = 0.03) and 0.14 mmol/L (95% CI: 0.06, 0.23 mmol/L; P = 0.0008), respectively. With identical soy protein intake, high isoflavone intake led to significantly greater decreases in serum LDL cholesterol than low isoflavone intake, demonstrating that isoflavones have LDL cholesterol-lowering effects independent of soy protein. KEY WORDS: * isoflavones * LDL * cholesterol * soy protein * meta-analysis

The aim of the present study was to evaluate whether olive oils high in phenolic compounds influence the oxidative/antioxidative status in humans. Healthy men (n = 12) participated in a double-blind, randomized, crossover study in which 3 olive oils with low (LPC), moderate (MPC), and high (HPC) phenolic content were given as raw doses (25 mL/d) for 4 consecutive days preceded by 10-d washout periods. Volunteers followed a strict very low-antioxidant diet the 3 d before and during the intervention periods. Short-term consumption of olive oils decreased plasma oxidized LDL (oxLDL), 8-oxo-dG in mitochondrial DNA and urine, malondialdehyde in urine (P < 0.05 for linear trend), and increased HDL cholesterol and glutathione peroxidase activity (P < 0.05 for linear trend), in a dose-dependent manner with the phenolic content of the olive oil administered. At d 4, oxLDL after MPC and HPC, and 8-oxo-dG after HPC administration (25 mL, respectively), were reduced when the men were in the postprandial state (P < 0.05). Phenolic compounds in plasma increased dose dependently during this stage with the phenolic content of the olive oils at 1, 2, 4, and 6 h, respectively (P < 0.01). Their concentrations increased in plasma and urine samples in a dose-dependent manner after short-term consumption of the olive oils (P < 0.01). In conclusion, the olive oil phenolic content modulated the oxidative/antioxidative status of healthy men who consumed a very low-antioxidant diet. KEY WORDS: * olive oil * phenolic compounds * oxidative stress * oxidized LDL * DNA damage

A diet rich in fruits, vegetables, and low-fat dairy foods has been shown to lower blood pressure (BP) when all foods are provided. We compared the effect on BP (measured at home) of 2 different self-selected diets: a low-sodium, high-potassium diet, rich in fruit and vegetables (LNAHK) and a high-calcium diet rich in low-fat dairy foods (HC) with a moderate-sodium, high-potassium, high-calcium DASH-type diet, high in fruits, vegetables and low-fat dairy foods (OD). Subjects were randomly allocated to 2 test diets for 4 wk, the OD and either LNAHK or HC diet, each preceded by a 2 wk control diet (CD). The changes in BP between the preceding CD period and the test diet period (LNAHK or HC) were compared with the change between the CD and the OD periods. Of the 56 men and 38 women that completed the OD period, 43 completed the LNAHK diet period and 48 the HC diet period. The mean age was 55.6 [+ or -] 9.9 ([+ or -]SD) years. There was a fall in systolic pressure between and the CD and OD [-1.8 [+ or -] 0.5 mm Hg (P < 0.001)]. Compared with OD, systolic and diastolic BPs fell during the LNAHK diet period [-3.5 [+ or -] 1.0 (P < 0.001) and -1.9 [+ or -] 0.7 (P < 0.05) mmHg, respectively] and increased during the HC diet period [+3.1 [+ or -] 0.9 (P < 0.01) and +0.8 [+ or -] 0.6 (P = 0.15) mm Hg, respectively]. A self-selected low-sodium, high-potassium diet resulted in a greater fall in BP than a multifaceted OD, confirming the beneficial effect of dietary intervention on BP in a community setting. KEY WORDS: * home blood pressure * dietary sodium * dietary potassium * dietary calcium * community setting

Complementary feeding practices are often inadequate in developing countries, resulting in a significant nutritional decline between 6 and 18 mo of age. We assessed the effectiveness of an educational intervention to promote adequate complementary feeding practices that would be feasible to sustain with existing resources. The study was a cluster randomized controlled trial in communities in the state of Haryana in India. We developed the intervention through formative research. Eight communities were pair matched on their baseline characteristics; one of each pair was randomly assigned to receive the intervention and the other to no specific feeding intervention. Health and nutrition workers in the intervention communities were trained to counsel on locally developed feeding recommendations. Newborns were enrolled in all of the communities (552 in the intervention and 473 in the control) and followed up every 3 mo to the age of 18 mo. The main outcome measures were weights and lengths at 6, 9, 12, and 18 mo and complementary feeding practices at 9 and 18 mo. All analyses were by intent to treat. In the overall analyses, there was a small but significant effect on length gain in the intervention group (difference in means 0.32 cm, 95% CI, 0.03, 0.61). The effect was greater in the subgroup of male infants (difference in mean length gain 0.51 cm, 95% CI 0.03, 0.98). Weight gain was not affected. Energy intakes from complementary foods overall were significantly higher in the intervention group children at 9 mo (mean [+ or -] SD: 1556 [+ or -] 1109 vs. 1025 [+ or -] 866 kJ; P < 0.001) and 18 mo (3807 [+ or -] 1527 vs. 2577 [+ or -] 1058 kJ; P < 0.001). Improving complementary feeding practices through existing services is feasible but the effect on physical growth is limited. Factors that limit physical growth in such settings must be better understood to plan more effective nutrition programs. KEY WORDS: * complementary feeding * educational intervention * child growth * gender * cluster randomization

Previous studies indicated that physical characteristics of food influence satiety, but the relative importance of the oral, gastric, and intestinal behaviors of the food is unclear. The aim of this study was to investigate the satiating effects of 2 types of alginates, which gel weakly or strongly on exposure to acid, compared with guar gum whose viscosity is unaffected by acid. Subjects (n = 12; 3 men, 9 women) ingested a 325-mL sweetened, milk-based meal replacer beverage on 4 separate occasions, either alone as a control or including 1% by weight alginate or guar gum. Intragastric gelling, gastric emptying, and meal dilution were assessed by serial MRI while satiety was recorded for 4 h. MR images showed that all of the meals became heterogeneous in the stomach except for guar, which remained homogeneous. The alginate meals formed lumps in the stomach, with the strong-gelling alginate producing the largest volume. Although gastric emptying was similar for all 4 meals, the sense of fullness at the same gastric volume was significantly greater for all 3 viscous meals than for the control. Compared with the control meal, the strong-gelling alginate (P = 0.031) and guar (P = 0.041) meals increased fullness at 115 min, and the strong-gelling alginate decreased hunger by the 115-min (P = 0.041) and 240-min (P = 0.041) time points. Agents that gel on contact with acid may be useful additions to weight-reducing diets. We hypothesize that this effect is due to distension in the gastric antrum and/or altered transport of nutrients to the small intestine in the lumps. KEY WORDS: * satiety * MRI * intragastric gelling * humans

Programs providing cash transfers to poor families, conditioned upon uptake of preventive health services, are common in Latin America. Because of the consistent association between undernutrition and poverty, and the role of health services in providing growth promotion, these programs are supposed to improve children's growth. The impact of such a program was assessed in 4 municipalities in northeast Brazil by comparing 1387 children under 7 y of age from program beneficiary households with 502 matched nonbeneficiaries who were selected to receive the program but who subsequently were excluded as a result of quasi-random administrative errors. Anthropometric status was assessed 6 mo after benefits began to be distributed, and beneficiary children were 0.13 Z-scores lighter (weight-for-age) than excluded children, after adjusting for confounders (P = 0.024). The children's growth trajectories were reconstructed by copying up to 10 recorded weights from their Ministry of Health growth monitoring cards and by relating each weight to the child's age, gender, and duration of receipt of the program benefit in a random effects regression model. Totals of 472 beneficiary and 158 excluded children under 3 y of age were included in this analysis. Each additional month of exposure to the program was associated with a rate of weight gain 31 g lower than that observed in excluded children of the same age (P < 0.001). This failure to respond positively to the program may have been due to a perception that benefits would be discontinued if the child started to grow well. Nutrition programs should guard against giving the impression that poor growth will be rewarded. KEY WORDS: * cash transfer programs * childhood growth * Latin America * Brazil * quasi-experiment

Many studies have reported comparable hemoglobin response in subjects given intermittent and daily iron supplements. However, the effect of intermittent iron supplementation on impaired cognitive function, one of the serious consequences of iron deficiency among children, has not been studied. We investigated the effects of 1 d/wk (weekly) and 5 d/wk (daily) iron supplementation on changes in results of intelligence quotient (IQ), Thai language, and mathematics tests among Thai primary schoolchildren. A double-blind, randomized, placebo-controlled trial was conducted. Primary schoolchildren (n = 397) were randomly assigned to receive iron supplements daily or weekly or placebo. Ferrous sulfate (300 mg) or placebo tablets were given under direct observation by the researcher for 16 wk. Changes in IQ, and Thai language and mathematics scores were then compared. The increases in hemoglobin concentration were comparable in the weekly and daily iron supplementation groups but serum ferritin increased more in the children supplemented daily. Children receiving daily iron supplements, however, had a significantly lower increase in IQ (3 [+ or -] 12 points) than those receiving the supplement weekly (6 [+ or -] 12 points) or placebo (6 [+ or -] 12 points), whereas the last-mentioned two groups did not differ. Z-scores of Thai language and mathematics test results did not differ among the groups. We conclude that weekly iron supplementation is the regimen of choice in this study community. KEY WORDS: * intermittent iron supplementation * cognitive function * IQ * school performance

Wasting can occur at an early stage of HIV infection. Both reduced energy intake and increased resting energy expenditure (REE) have been considered as factors in wasting with predominant lean body mass loss, suggesting disturbances of protein metabolism. Our aim was to study protein-energy metabolism in relation to body composition and oral energy intake in asymptomatic patients with HIV infection but receiving no active antiretroviral therapy. Stable-weight asymptomatic male patients (n = 8) at stage A of HIV infection with a detectable viral load were compared with 9 healthy control men. Protein metabolism was studied in the postabsorptive state using a primed constant infusion of L-[1-[sup.13]C]leucine and L-[2-[sup.15]N]glutamine. REE was studied by indirect calorimetry, body composition by bioelectrical impedance, and energy intake by dietary records. BMI and lean body mass did not differ between patients and controls. In HIV-infected subjects, energy intake, protein breakdown, protein synthesis, and REE were 57% (P < 0.05), 18% (P < 0.05), 22% (P < 0.05) and 14% (P < 0.05) greater than in controls, respectively. REE and protein breakdown were correlated (r = 0.73, P < 0.05). The hormonal profile was normal in HIV-infected subjects with the exception of low urinary C-peptide and plasma reverse triiodothyronine. Plasma interleukin-6 and tumor necrosis factor-[alpha] were greater than in controls, but energy intake was 1.53 times the REE in the HIV-infected men. Thus, at the asymptomatic stage of HIV infection, increased protein turnover contributes to the increase in the REE. Moderate hyperphagia, which occurred despite increased levels of cytokines, in conjunction with increased protein synthesis maintains a normal body composition, without significant loss of lean body mass. KEY WORDS: * HIV * body composition * energy expenditure * hyperphagia * protein metabolism

Between 6 and 12 mo of age, blood levels of the (n-3) long-chain PUFA, docosahexaenoic acid (DHA), in breast-fed infants typically decrease due to diminished maternal DHA stores and the introduction of DHA-poor solid foods displacing human milk as the primary source of nutrition. Thus, we utilized a randomized, clinical trial format to evaluate the effect of supplemental DHA in solid foods on visual development of breast-fed infants with the primary outcome, sweep visual-evoked potential (VEP) acuity, as an index for maturation of the retina and visual cortex. At 6 mo of age, breast-fed infants were randomly assigned to receive 1 jar (113 g)/d of baby food containing egg yolk enriched with DHA (115 mg DHA/100 g food; n = 25) or control baby food (0 mg DHA; n = 26). Gravimetric measures were used to estimate the supplemental DHA intake which was 83 mg DHA/d in the supplemented group and 0 mg/d in controls. Although many infants in both groups continued to breast-feed for a mean of 9 mo, RBC DHA levels decreased significantly between 6 and 12 mo (from 3.8 to 3.0 g/100 g total fatty acids) in control infants, whereas RBC DHA levels increased by 34% from 4.1 to 5.5 g/100 g by 12 mo in supplemented infants. VEP acuity at 6 mo was 0.49 logMAR (minimum angle of resolution) and improved to 0.29 logMAR by 12 mo in controls. In DHA-supplemented infants, VEP acuity was 0.48 logMAR at 6 mo and matured to 0.14 logMAR at 12 mo (1.5 lines on the eye chart better than controls). At 12 mo, the difference corresponded to 1.5 lines on the eye chart. RBC DHA levels and VEP acuity at 12 mo were correlated (r = -0.50; P = 0.0002), supporting the need of an adequate dietary supply of DHA throughout 1 y of life for neural development. KEY WORDS: * (n-3) fatty acids * docosahexaenoic acid * neural development

Dietary CLA isomers were shown to reduce adipose tissues in growing animals, mainly in mice, but their effects in adult animals remain unclear. This study was conducted to determine whether these effects depend on the isomer fed, on physical activity, or on the initial level of body fat. Male Wistar rats (4 mo old) were fed for 6 wk diets containing either no CLA, the cis-9, trans-11 CLA isomer (10 g/kg), the trans-10, cis-12 CLA isomer (10 g/kg), or both isomers (10 g/kg each). Half of the rats were assigned to exercise by treadmill running (1 h/d, 22 m/min). The initial body fat level was normal (12.7%) in a first trial, and high (18.9%) in a second trial. Chemical and anatomical body compositions were determined by chemical analysis and organ dissection. In both trials, the CLA diets, whatever the isomer, had no effect on food intake and body weight changes, on body chemical composition (fat, protein and water contents or gains), or on the body anatomical composition (weights or gains in epididymal and perirenal adipose tissues, in liver and in 4 muscles). There was no interaction between CLA treatment and physical activity. In conclusion, adult male rats do not appear to be responsive to the fat-to-lean partitioning effect of CLA described in growing rats. This was not affected by exercise or initial body fat level. KEY WORDS: * CLA isomers * exercise * body composition * rats

The search for a reliable, convenient indicator of Zn status was the focus of research for several decades. Plasma Zn concentration is still the most widely used clinical measurement, despite the known problems of interpretation. More recently, researchers suggested that isotopically determined kinetic parameters, such as the exchangeable Zn pool (EZP), may more accurately and reliably reflect body Zn status. The objective of this study was to examine the relationship between net body Zn loss and gain during acute changes in dietary Zn intake with biochemical and kinetic indices of Zn status. Five men participated in an 85-d Zn depletion/repletion study. Net body Zn loss and gain were determined from the difference between dietary plus intravenously administered Zn and Zn excretion. Biochemical indicators of Zn status included plasma Zn, plasma alkaline phosphatase activity, and plasma retinol binding protein concentration. Following intravenous administration of [sup.70]Zn or [sup.67]Zn, a compartmental model was used to determine EZP mass, fractional Zn absorption, endogenous zinc excretion (EZE), and plasma Zn flux. The changes in total body zinc correlated best with changes in plasma Zn ([r.sup.2] = 0.826, P < 0.001), EZE ([r.sup.2] = 0.773, P < 0.001), and plasma Zn flux ([r.sup.2] = 0.788, P < 0.001). This study confirms that plasma Zn concentration is a valid indicator of whole-body Zn status in the absence of confounding factors; however, further research is needed to determine how kinetic parameters respond to conditions where plasma Zn concentration is known to be unreliable. KEY WORDS: zinc status biochemical indices * stable isotopes * kinetic analysis * compartmental model

Much remains unknown of the phylogeny and evolution of Mycobacterium tuberculosis, an organism that kills 2 million people annually. Using a population-based approach that analyzes multiple loci around the chromosome, [...]

Background. Disability in basic activities of daily living (ADLs) implies a loss of independence and increases the risk for hospitalization, nursing home admission, and death. Little is known about ways by which ADL disability can be prevented or reversed. The authors evaluated the efficacy of the Health Enhancement Program in preventing and reducing ADL disability in community-dwelling older adults. Methods. The authors analyzed data from a 12-month, randomized, single-blinded, controlled trial of a disability prevention, chronic disease self-management program involving 201 adults aged 70 years and older that was conducted from February 1995 to June 1996 at a senior center in western Washington state. Activities of daily living disability incidence, improvement, and worsening were assessed using intention-to-treat methods. Results. The cumulative incidence of ADL disability among those who were not ADL disabled at baseline (n = 56 in the intervention group, n = 57 in the control group) was modestly lower in the intervention group than in the control group at 12 months (14.3% vs 21.3 %, p = .466). Cumulative improvement in ADL function among those who reported any ADL disability at baseline (n = 41 in the intervention group, n = 43 in the control group) was greater in the intervention group at 12 months (80.5% vs 46.5%, p = .026). The likelihood for ADL improvement was greater in the intervention group compared with controls at 12 months (adjusted hazard ratio, 1.84; 95% confidence interval, 1.05 to 3.22; p = .020). Cumulative worsening of ADL function was slightly lower in the intervention group at 12 months (18.6% vs 26.5%, p = .237). Intervention participants tended to be at lower risk for ADL worsening (adjusted hazard ratio, 0.71; 95% confidence interval, 0.38 to 1.30; p = .266) compared with control participants. Conclusion. The Health Enhancement Program intervention led to improved ADL functioning in those who were disabled initially and thereby offers a promising strategy for limiting or reversing functional decline in disabled elderly persons.

This article, based on a Lawton Award Lecture, addresses the subject of the need to enhance the evidence base in our field in order to influence processes of policy development. Four issues are identified as critical to this: theory-driven targets of public health significance, use of appropriate and sophisticated approaches to research design and statistical modeling, development of instruments and measures, and conclusions that make a difference. Incentives are discussed with particular attention to regulatory approaches. A broad view of research is taken, with examples from studies of Alzheimer's disease and depression in late life. I conclude that new approaches to methodology will enhance our capacity to translate exciting new findings from the basic sciences into the development of therapeutics and that this will, in turn, enhance our capacity to inform the development of public policy. Key Words: Clinical trials, Alzheimer's disease, Depression, Methodology

The final results of the European Study Group for Pancreatic Cancer 1 Trial are reported and the interim results are updated. It is concluded that adjuvant chemotherapy has a significant survival benefit in patients with resected pancreatic cancer, whereas adjuvant chemoradiotherapy has a deleterious effect on survival.

The efficacy and safety of using fentanyl hydrochloride in comparison to a standard intravenous morphine patient-controlled pump is examined. The transdermal patient-controlled analgesia (PCA) delivery system is equivalent to a standard morphine intravenous (IV) patient-controlled analgesia (PCA) regimen in postoperative pain management.

A healthy 16 year old girl presents to her physician a two day history of sore throat, fatigue, fever and vomiting. In this case, the impatient clinicians initially marginalize the neck-related symptoms, whereas advance tests place the systemic findings into the context of antecedent pharyngitis.

A BODE index, a simple multidimensional grading system, was constructed on the basis that four factors predicted the risk of death in patients with chronic obstruction pulmonary disease (COPD), the body-mass index (B), the degree of airflow construction(O), dyspnea(D), and exercise capacity(E). After a trial done on 207 patients, it was concluded that the BODE index is better than the previous methods at predicting the risk factors causing death in patients with COPD.

The Women's Health Initiative (WHI) conducted a trial of estrogen and progestin in post-menopausal women. The trial concluded that relatively short-term use of estrogen plus progestin was associated with a decreased risk of colorectal cancer. However, colorectal cancer in women who took both were diagnosed at a more advanced stage than those who took placebo.

An updated and improved analysis of the European Study Group for Pancreatic Cancer (ESPAC-1) trial, the largest randomized trial of adjuvant therapy for pancreatic cancer, is reported. The attempts made to correct some of the limitations of the previous report are discussed.

A randomized trial was conducted to study the effect of self-help materials and telephone counseling on increasing cessation of smoking in teenagers. Results indicate that while self-help materials are effective, telephone-counseling approaches need more refinement to achieve the success got with adult populations.

The efficacy of involvement depending on the idea of implementation intentions to lessen the dietary fat intake is analyzed. The results are debated in relation to the utility of implementation intentions against the organized interventions to modify the behavior in general populations.

The impact of the intervention on multiple versus a single health behavior with adolescents is evaluated. Interventions are compared targeting physical activity and nutrition (PAN) concurrently verus physical activity (PA) alone.

Three trials of HIV prevention mediations instated to notify commissioning policies were examined. Research infers that though trials were produced through intricate processes involving numerous agencies, HIV commissioners were insignificant initiators.