Novel Measurement of the Neutron Magnetic Form Factor from A=3 Mirror Nuclei.

The electromagnetic form factors of the proton and neutron encode information on the spatial structure of their charge and magnetization distributions. While measurements of the proton are relatively straightforward, the lack of a free neutron target makes measurements of the neutron's electromagnetic structure more challenging and more sensitive to experimental or model-dependent uncertainties. Various experiments have attempted to extract the neutron form factors from scattering from the neutron in deuterium, with different techniques providing different, and sometimes large, systematic uncertainties. We present results from a novel measurement of the neutron magnetic form factor using quasielastic scattering from the mirror nuclei ^{3}H and ^{3}He, where the nuclear effects are larger than for deuterium but expected to largely cancel in the cross-section ratios. We extracted values of the neutron magnetic form factor for low-to-modest momentum transfer, 0.6

Perioral movements and sucking pattern during bottle feeding with a novel, experimental teat are similar to breastfeeding.

OBJECTIVE: To measure intraoral pressure and perioral movement in infants during breastfeeding (BF) and feeding with experimental teat (ET). The teat has a wide base, firm shaft and a valve at the base, such that milk flows only when the baby provides a hold pressure. STUDY DESIGN: Twenty healthy term infants, between 1 and 8 months old, were enrolled in the study. Feeding sessions (BF and ET) were recorded using a digital video camera. During both BF and ET feeding sessions, recordings during feeding were taken of jaw and throat movements (n=20) as well as intraoral pressure (n=18). The efficiency of milk transfer and the angle of the mouth were also measured. RESULT: There was no significant difference in either the jaw or throat movements between BF and ET. The sucking burst pattern, the efficiency (ml min(-1)), and the angle of the mouth did not differ between both feeding methods. The intraoral negative pressure observed during ET was significantly smaller than that observed during BF. CONCLUSION: There were no significant differences in perioral movements. Although the value was smaller, a hold pressure was observed during ET. From these results, the novel, ET may decrease BF problems related to bottle use.

The diagnostic accuracy of high-resolution endoscopy, autofluorescence imaging and narrow-band imaging for differentially diagnosing colon adenoma.

BACKGROUND AND STUDY AIMS: Conventional colonoscopy can result in unnecessary biopsy or endoscopic resection due to its inability to distinguish adenomas from hyperplastic polyps. This study therefore evaluated the efficacy of high-resolution endoscopy (HRE), autofluorescence imaging (AFI), and narrow-band imaging (NBI) in discriminating colon adenoma from hyperplastic polyps. PATIENTS AND METHODS: This was a prospective multicenter study in patients undergoing AFI and NBI examinations. HRE, AFI, and NBI images were classified into two groups based on morphological characteristics, the predominant color intensities, and the visibility of meshed capillary vessels, respectively. Each of the endoscopic photographs were independently evaluated by a single endoscopist. The images were then assessed by three specialists and three residents, the latter having performed < 500 colonoscopies and < 30 NBI and AFI examinations. Diagnostic test statistics were calculated to compare the accuracy in differentiating colon adenoma from hyperplastic polyps for each method. RESULTS: A total of 183 patients were enrolled in the study and 339 adenomas and 85 hyperplastic polyps were identified. AFI and NBI could distinguish adenoma from hyperplastic polyps with an accuracy of 84.9 % and 88.4 %, respectively, whereas HRE exhibited an accuracy of 75.9 %. In the 358 lesions in which the AFI diagnosis was consistent with that of NBI, the accuracy, sensitivity, and specificity were high, at 91.9 %, 92.7 %, and 92.9 %, respectively. During the study comparing specialists and residents, AFI and NBI dramatically improved the diagnostic accuracy of residents from 69.1 % to 86.1 % and 84.7 %, respectively. CONCLUSIONS: Both AFI and NBI are considered to be feasible tools that can discriminate colon adenoma from hyperplastic polyps, and their use may be particularly beneficial for less-experienced endoscopists.

Hydrogen sensing properties of protective-layer-coated single-walled carbon nanotubes with palladium nanoparticle decoration.

Protective-layer-coated single-walled carbon nanotubes (SWNTs) with palladium nanoparticle decoration (Pd-SiO(2)-SWNTs) were fabricated and their sensing properties for hydrogen (H(2)) were investigated. SWNTs were coated with a 3-4 nm thick SiO(2) layer by pulsed laser deposition and subsequently decorated with Pd nanoparticles by electron beam evaporation. Even though the SWNTs were completely surrounded by a protective layer, Pd-SiO(2)-SWNTs responded to H(2) down to a concentration of 1 part per million. Compared with the Pd nanoparticle-decorated SWNTs without a protective layer (Pd-SWNTs), Pd-SiO(2)-SWNTs exhibited highly stable sensor responses with variations of less than 20%; Pd-SWNTs showed a variation of 80%. The density of the Pd-SWNTs significantly decreased after the sensing test, while that of the Pd-SiO(2)-SWNTs with the netlike structure remained unchanged. The hydrogen sensing mechanism of the Pd-SiO(2)-SWNTs was attributed to the chemical gating effect on the SWNTs due to dipole layer formation by hydrogen atoms trapped at the Pd-SiO(2) interface. Moreover, the relationship between H(2) concentration and sensor response can be described by the Langmuir isotherm for dissociative adsorption.

Maturational changes in the feeding behaviour of infants - a comparison between breast-feeding and bottle-feeding.

AIM: To obtain a better understanding of the changes in feeding behaviour from 1 to 6 months of age. By comparing breast- and bottle-feeding, we intended to clarify the difference in longitudinal sucking performance. METHODS: Sucking variables were consecutively measured for 16 breast-fed and eight bottle-fed infants at 1, 3 and 6 months of age. RESULTS: For breast-feeding, number of sucks per burst (17.8 +/- 8.8, 23.8 +/- 8.3 and 32.4 +/- 15.3 times), sucking burst duration (11.2 +/- 6.1, 14.7 +/- 8.0 and 17.9 +/- 8.8 sec) and number of sucking bursts per feed (33.9 +/- 13.9, 28.0 +/- 18.2 and 18.6 +/- 12.8 times) at 1, 3 and 6 months of age respectively showed significant differences between 1 and 6 months of age (p < 0.05). The sucking pressure and total number of sucks per feed did not differ among different ages. Bottle-feeding resulted in longer sucking bursts and more sucks per burst compared with breast-feeding in each month (p < 0.05). CONCLUSION: The increase in the amount of ingested milk with maturation resulted from an increase in bolus volume per minute as well as the higher number of sucks continuously for both breast- and bottle-fed infants.

Evaluation of the effect of 4 months of risedronate therapy on femoral strength using femoral strength analysis tools.

The effect of risedronate (2.5 mg once daily) on femoral strength was evaluated using Advanced Hip Assessment (AHA) for the first time in Japan. In total, 104 patients with primary osteoporosis and available data on bone mineral density (BMD; lumbar spine/proximal femur), urinary NTx (cross-linked N-telopeptides of type I collagen) and AHA-based parameters collected before and after 4 months of risedronate therapy were included in the analyses. Change and percentage change from baseline in these parameters were determined. Percentage change in femur strength index was 7.9 +/- 21.1% and 5.5 +/- 18.0% for the right and left femurs, respectively; both increases were statistically significant. Cross-sectional moment of inertia, cross-sectional area and mean neck width in the femoral neck region of interest also increased significantly in both femurs. Percentage change in lumbar spine BMD (L2 - L4) was 3.0 +/- 3.7%, and proximal femoral BMD was 1.1 +/- 3.1% and 0.7 +/- 3.2% in the right and left femurs, respectively, all showing a significant increase from baseline. Percentage change in urinary NTx was -41.5 +/- 30.5%, which was a significant decrease. Using AHA, this study showed that, in patients with primary osteoporosis, risedronate improved BMD and bone quality, thereby enhancing femoral strength as early as 4 months after treatment initiation.

Incidence and predicting factors of hypozincemia in very-low-birth-weight infants at near-term postmenstrual age.

We prospectively investigated serum zinc (Zn) concentrations and clinical factors in 118 very-low-birth-weight infants with a gestational age of 29.5 +/- (SD) 2.5 weeks and a birth weight of 1,194 +/- 254 g at near-term postmenstrual age. The 25th percentile of the serum Zn concentration was 7.0 micromol/l. The infants whose serum Zn concentrations were less than 7.0 micromol/l (defined as hypozincemia) did not have apparent symptoms of Zn deficiency. Multivariate logistic regression analyses demonstrated that hypozincemia was associated with factors such as weight gain (1-g/kg/day increase of weight; OR 1.1762, 95% CI 1.0414-1.3286) and serum albumin concentration (1-g/dl increase of serum albumin; OR 0.0816, 95% CI 0.0152-0.4372). The types of milk feeding did not affect the serum Zn concentrations in the study subjects. This study suggests that hypozincemia in very-low-birth-weight infants at near-term postmenstrual age is associated with greater weight gain and lower serum albumin concentration. Nutritional supply of Zn by human milk fortifier and preterm formula does not appear to meet the demands of rapidly growing very-low-birth-weight infants.

Leukemoid reaction and chronic lung disease in infants with very low birth weight.

OBJECTIVES: To analyze the relationship between the leukemoid reaction and chronic lung disease in very-low-birth-weight (VLBW) infants. METHODS: Neonates born weighing less than 1500 g without evidence of congenital anomalies and admitted to our hospital from October 1985 to December 1999 comprised our study. Leukemoid reaction was defined as a peripheral white blood cell (WBC) count of > or = 50 x 10(3)/microl. The infants who demonstrated a leukemoid reaction formed the study group, while the remainder formed the control group. The relationship between neonatal variables and WBC counts was studied. RESULTS: Fourteen of the 486 infants demonstrated WBC counts of > or = 50 x 10(3)/microl, with an incidence of 2.9%. Univariate analysis demonstrated a significant association between a leukemoid reaction and chronic lung disease following intrauterine infection. CONCLUSION: A leukemoid reaction was observed in 2.9% of VLBW infants in our neonatal intensive care unit. A significant association was demonstrated between the leukemoid reaction and chronic lung disease following intrauterine infection.

Protective effects of urinary trypsin inhibitor (UTI) on hepatic microvasculature in hypotensive brain-dead rats.

BACKGROUND/AIMS: We examined the protective effects of a protease inhibitor, urinary trypsin inhibitor (UTI), on livers of brain dead rats associated with systemic hemodynamic instability. METHODS: Brain death was induced by inflating a balloon catheter placed in the epidural space in rats followed by intravenous administration of UTI for 6 h. The hemodynamic, functional and morphological changes in the liver were examined. RESULTS: The induction of brain death resulted in a significant decrease in both mean arterial pressure (MAP) and hepatic tissue flow (HTF), and an increase in serum AST and cytokines such as tumor necrosis factor (TNF)-alpha and cytokine-induced neutrophil chemoattractant (CINC). An increase in the number of sequestered neutrophils and enhanced expressions of intercellular adhesion molecules (ICAM)-1 and CINC were also noted in the liver. The treatment with UTI significantly restored HTF to basal level without affecting MAP, and decreased the number of sequestered neutrophils in the hepatic sinusoids, suppressed the expression of ICAM-1 and CINC in the sinusoids, inhibited the production of serum TNF-alpha and CINC, and inactivated Kupffer cells. CONCLUSION: Intravenous administration of UTI is likely to ease unfavorable effects on the hepatic microvasculature evoked by brain death.

Estimated nutritional intake based on the reference growth curves for extremely low birthweight infants.

BACKGROUND: Although the optimal goal of extremely low birthweight (ELBW) infants has been debated, it can be argued that the best nutritional strategy for ELBW infants is one which achieves better growth while preventing neurological sequelae due to nutritional inadequacy, even if it does not mimic fetal growth. Our aim is to propose an advisable and practically feasible nutritional intake for ELBW infants. METHODS: We retrospectively investigated the nutritional intake in 16 ELBW infants (gestational age 26.7 weeks, birthweight 879.6 g), who exceeded the standard growth curves for Japanese infants of ELBW. We also analyzed the nutritional composition of human milk from 15 mothers delivering before term (PT milk) until the 12th week of lactation. The nutritional intake was calculated according to the composition of the parenteral and enteral regimen. RESULTS: The infants tolerated more than 100 mL/kg per day of milk until the fourth week of life. An average weight gain of more than 15 g/kg per day was achieved by the sixth week. An advisable nutritional intake capable of sustaining ELBW infants in a stable growing phase was calculated as the sum of the mean plus 1SD of the daily nutritional intake. CONCLUSIONS: To exceed the ordinary growth curves for ELBW Japanese infants, it was suggested that more than 100 mL milk/kg per day could be fed until the fourth week of life, while the advisable daily intake of nutrients after six weeks of life should be as follows: water 160 mL/kg, protein 3.2 g/kg, fat 7.4 g/kg, carbohydrate 12.8 g/kg, energy 544 kJ/kg, the following minerals in mg/kg: sodium 45, chloride 82, potassium 110, calcium 140, phosphorus 70, magnesium 11, zinc 0.5 and copper at 60 micrograms/kg. Further studies will be needed to confirm the safety and effectiveness of this advisable intake for ELBW infants.

Evaluation of bone density in newborn infants by computed x-ray densitometry.

We evaluated bone density in term and preterm infants using computed x-ray densitometry, which permits measurement of bone density with minimal disturbance to the infants in their incubators. Bone density, bone width, and bone length of the right radius were determined in 155 infants of appropriate weights for their gestational ages (23 to 41 weeks). A curve for intrauterine bone growth was extrapolated from these data. The mean coefficients of variations for variabilities for intra- and interobserver error for all measurements were < 3.5%. In 18 infants, measurements of the right forearm were obtained in two positions to confirm the validity of densitometric measurements. The mean coefficients of variation were 3.42% for bone density, 3.48% for bone width, and 0.21% for bone length. Bone density was significantly correlated with gestational age (r = 0.924) and birth weight (r = 0.921). Bone width and length were also correlated with gestational age (r = 0.866 and 0.937) and birth weight (r = 0.878 and 0.954). Our results suggest that computed x-ray densitometry is a useful method for evaluation of bone density in preterm infants, including those in an intensive care environment.

Effect of body position on the blood gases and ventilation volume of infants with chronic lung disease before and after feeding.

The effect of body position before and after tube feeding was evaluated in six extremely immature infants who were being mechanically ventilated because of chronic lung disease. Their mean birthweight and gestational age were 722.7 g (range, 540 to 994) and 24.9 weeks (range, 23.9 to 26.0), respectively. This study was performed at a mean postnatal age of 47.5 days (range, 21 to 85 days). The prone position resulted in a significant increase in arterial oxygen saturation before and after feeding, whereas the tidal volume demonstrated an increase only before feeding. Also the prone position showed a significant decrease in heart rate before and after feeding and a tendency to decrease transcutaneous carbon dioxide tension values before feeding. There were no significant differences in minute ventilation despite increased tidal volume in the prone position, most likely due to a decrement of the spontaneous respiratory rate in the prone positioning. We conclude that the prone position may offer an advantage over the supine position in the management of extremely immature infants with chronic lung disease before and after feeding.

Nutrient balance, metabolic response, and bone growth in VLBW infants fed fortified human milk.

The effects of fortification of preterm human milk were evaluated by comparing two groups of very low birth weight infants (birth weight < or = 1300 g, gestational age < or = 30 weeks): six fed preterm human milk fortified with a commercially available protein-mineral supplement (protein 0.7 g/dl, calcium 90 mg/dl, phosphorus 45 mg/dl) and seven fed unfortified preterm human milk. Nitrogen and energy balance studies were performed at an average age of 56 postnatal days. Nitrogen retention in the fortified group (348.2 +/- 70.5 mg/kg/day) was significantly greater than that in the unfortified group (196.0 +/- 50.0 mg/kg/day) and similar to that of fetuses of comparable gestational age. Energy stored by the two groups did not differ. At age 8 weeks, the infants in the fortified group had higher serum protein, higher serum albumin, and better mineral status (higher serum calcium and phosphorus and lower alkaline phosphatase and renal tubular reabsorption of phosphate). The bone density and width of the distal third radius, as measured by X-ray microdensitometry, were greater in the fortified group than in the unfortified group 12 weeks after birth. These results suggest that the supplement corrects any nutritional inadequacies of preterm human milk for very low birth weight infants.

Postnatal reference growth curves for very low birth weight infants.

To construct standard growth curves for Japanese infants of very low birth weight (VLBW) with birth weights of 500-1499 g, we reviewed longitudinal data provided by 54 neonatal intensive care units in Japan. A total of 382 surviving singleton infants, appropriate for gestational age infants, and who were free of neurological sequelae at more than 2.5 years of age, were enrolled. Growth curves, including body weight, head circumference and body length were generated for four ranges of birth weight: 500-749 g, 750-999 g, 1000-1249 g, and 1250-1499 g. When compared with previously published growth data from western countries, Japanese infants of VLBW showed greater weight loss, regained birth weight more slowly, and exhibited smaller average gains in weight, head circumference, and body length. The growth curves reported in western countries may not be useful as reference standards of early postnatal growth in Japan. The new growth curves are a more accurate reflection of current in-hospital growth trends in Japan.

Efficacy of synchronized IMV on weaning neonates from the ventilator.

This study evaluated the efficacy of a new patient-triggered ventilator that triggered the patient's inspiratory effort by detecting the change in airflow by means of a 'hot wire' anemometer. This ventilator was used in both the conventional and the synchronized intermittent mandatory ventilation (SIMV) modes in seven neonates. Values for blood gas, spontaneous breathing rate, tidal volume of spontaneous breaths and minute volume were compared in all seven neonates. The resistive work of spontaneous breathing in five neonates, obtained with synchronized intermittent mandatory ventilation was compared with the values obtained using conventional mechanical ventilation on the previous day of weaning from the ventilator. At each the inflation time studied (0.4, 0.3, 0.24 s), all mechanical breath occurred synchronously with infants' inspiratory efforts. The median trigger delay was 80 ms. Oxygenation was improved on the new system compared with the conventional system. Tidal volume of spontaneous breathing and minute volume were increased with SIMV compared with conventional mechanical ventilation, although the resistive work of spontaneous breathing was decreased with SIMV. The tidal volume of spontaneous breaths was more constant with SIMV versus conventional mechanical ventilation. Thus, the airway flow-triggered SIMV may lessen inspiratory muscle fatigue during weaning process. We conclude that the SIMV is useful in weaning neonates from the ventilator.

Postnatal growth curves of very low birthweight Japanese infants.

To construct standard growth curves for Japanese infants of very low birthweight, longitudinal data provided by 47 neonatal centers in Japan were reviewed. Data were collected on the growth of infants admitted to those units during 1986 and 1987 and who survived beyond 3 years of age. A total of 379 singleton infants, who were free of neurological sequelae and appropriate for gestational age, were enrolled. Those whose birthweights were more than 600 g and less than 1,500 g were grouped into nine weight categories separated by increments of 100 g. Data on the increase in weight and head circumference were compiled and analyzed until more than half the infants in each weight category had been discharged from each site. Growth curves of bodyweight and head circumference in the nine groups were constructed using polynomial regression analysis to define the curve of best fit. With increasing prematurity, significant trends of greater weight loss (P < 0.05), longer time to reach the lowest weight (P < 0.01) and a longer time to regain birthweight (P < 0.01) were observed. In addition, there was a significantly higher incidence of chronic lung disease in such groups (P < 0.0001). Growth curves were characterized by the average clinical profiles in each of the nine groups. We believe that these data will be useful in evaluating the growth of very low birthweight infants being cared for in modern neonatal intensive care units in Japan.

Effect of mean airway pressure on bronchial mucosal blood flow in rabbits with oleic acid-induced injury.

The effects of mean airway pressure (MAP) on bronchial mucosal blood flow at the carina in nine anesthetized adult rabbits undergoing high frequency ventilation were studied. The animals were given oleic acid to diminish lung compliance and to exclude the influences of increasing MAP on systemic venous return. Mucosal blood flow decreased significantly when MAP exceeded 14 cmH2O. Mucosal blood velocity tended to decrease as higher levels of MAP were applied. Mucosal blood volume decreased significantly when MAP exceeded 20 cmH2O. Hemodynamics, arterial blood gas values and pH were not changed significantly. Our data demonstrate that bronchial mucosal blood flow decreases at high levels of MAP even if cardiac output remains constant. Hence this decrease of bronchial mucosal blood flow may be due to the transmission of pressure to submucosal bronchial capillaries.