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 Collapse

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Affiliation(s)

S N Santiesteban University of New Hampshire, Durham, New Hampshire 03824, USA
S Li University of New Hampshire, Durham, New Hampshire 03824, USA Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
D Abrams University of Virginia, Charlottesville, Virginia 22904, USA
S Alsalmi Kent State University, Kent, Ohio 44240, USA King Saud University, Riyadh 11451, Kingdom of Saudi Arabia
D Androic University of Zagreb, Zagreb, Croatia
K Aniol California State University, Los Angeles, California 90032, USA
J Arrington Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA Argonne National Laboratory, Lemont, Illinois 60439, USA
T Averett William and Mary, Williamsburg, Virginia 23185, USA
C Ayerbe Gayoso William and Mary, Williamsburg, Virginia 23185, USA
J Bane University of Tennessee, Knoxville, Tennessee 37966, USA
S Barcus William and Mary, Williamsburg, Virginia 23185, USA
J Barrow University of Tennessee, Knoxville, Tennessee 37966, USA Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
A Beck Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
V Bellini INFN Sezione di Catania, Italy
H Bhatt Mississippi State University, Mississippi State, Mississippi 39762, USA
D Bhetuwal Mississippi State University, Mississippi State, Mississippi 39762, USA
D Biswas Hampton University, Hampton, Virginia 23669, USA
A Camsonne Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
J Castellanos Florida International University, Miami, Florida 33199, USA
J Chen William and Mary, Williamsburg, Virginia 23185, USA
J-P Chen Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
D Chrisman Michigan State University, East Lansing, Michigan 48824, USA
M E Christy Hampton University, Hampton, Virginia 23669, USA Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
C Clarke Stony Brook, State University of New York, New York 11794, USA
S Covrig Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
R Cruz-Torres Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
D Day University of Virginia, Charlottesville, Virginia 22904, USA
D Dutta Mississippi State University, Mississippi State, Mississippi 39762, USA
E Fuchey University of Connecticut, Storrs, Connecticut 06269, USA
C Gal University of Virginia, Charlottesville, Virginia 22904, USA
F Garibaldi INFN, Rome, Italy
T N Gautam Hampton University, Hampton, Virginia 23669, USA
T Gogami Tohoku University, Sendai, Japan
J Gomez Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
P Guèye Hampton University, Hampton, Virginia 23669, USA Michigan State University, East Lansing, Michigan 48824, USA
T J Hague Kent State University, Kent, Ohio 44240, USA
J O Hansen Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
F Hauenstein Old Dominion University, Norfolk, Virginia 23529, USA
W Henry Temple University, Philadelphia, Pennsylvania 19122, USA
D W Higinbotham Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
R J Holt Argonne National Laboratory, Lemont, Illinois 60439, USA
C Hyde Old Dominion University, Norfolk, Virginia 23529, USA
K Itabashi Tohoku University, Sendai, Japan
M Kaneta Tohoku University, Sendai, Japan
A Karki Mississippi State University, Mississippi State, Mississippi 39762, USA
A T Katramatou Kent State University, Kent, Ohio 44240, USA
C E Keppel Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
P M King Ohio University, Athens, Ohio 45701, USA
L Kurbany University of New Hampshire, Durham, New Hampshire 03824, USA
T Kutz Stony Brook, State University of New York, New York 11794, USA
N Lashley-Colthirst Hampton University, Hampton, Virginia 23669, USA
W B Li William and Mary, Williamsburg, Virginia 23185, USA
H Liu Columbia University, New York, New York 10027, USA
N Liyanage University of Virginia, Charlottesville, Virginia 22904, USA
E Long University of New Hampshire, Durham, New Hampshire 03824, USA
A Lovato Physics Division, Argonne National Laboratory, Argonne, Illinois 60439, USA Computational Science Division, Argonne National Laboratory, Argonne, Illinois 60439, USA INFN-TIFPA Trento Institute for Fundamental Physics and Applications, 38123 Trento, Italy
J Mammei University of Manitoba, Winnipeg, MB R3T 2N2, Canada
P Markowitz Florida International University, Miami, Florida 33199, USA
R E McClellan Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
F Meddi INFN, Rome, Italy
D Meekins Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
R Michaels Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
M Mihovilovič Jožef Stefan Institute, 1000 Ljubljana, Slovenia Faculty of Mathematics and Physics, University of Ljubljana, 1000 Ljubljana, Slovenia Institut für Kernphysik, Johannes Gutenberg-Universität Mainz, DE-55128 Mainz, Germany
A Moyer Christopher Newport University, Newport News, Virginia 23606, USA
S Nagao Tohoku University, Sendai, Japan
D Nguyen University of Virginia, Charlottesville, Virginia 22904, USA
M Nycz Kent State University, Kent, Ohio 44240, USA
M Olson Saint Norbert College, De Pere, Wisconsin 54115, USA
L Ou Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
V Owen William and Mary, Williamsburg, Virginia 23185, USA
C Palatchi University of Virginia, Charlottesville, Virginia 22904, USA
B Pandey Hampton University, Hampton, Virginia 23669, USA
A Papadopoulou Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
S Park Stony Brook, State University of New York, New York 11794, USA
T Petkovic University of Zagreb, Zagreb, Croatia
S Premathilake University of Virginia, Charlottesville, Virginia 22904, USA
V Punjabi Norfolk State University, Norfolk, Virginia 23529, USA
R D Ransome Rutgers University, New Brunswick, New Jersey 08854, USA
P E Reimer Argonne National Laboratory, Lemont, Illinois 60439, USA
J Reinhold Florida International University, Miami, Florida 33199, USA
S Riordan Argonne National Laboratory, Lemont, Illinois 60439, USA
N Rocco Theoretical Physics Department, Fermi National Accelerator Laboratory, Batavia, Illinois 60510, USA
V M Rodriguez División de Ciencias y Tecnología, Universidad Ana G. Méndez, Recinto de Cupey, San Juan 00926, Puerto Rico
A Schmidt Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
B Schmookler Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
E P Segarra Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
A Shahinyan Yerevan Physics Institute, Yerevan, Armenia
S Širca Jožef Stefan Institute, 1000 Ljubljana, Slovenia Faculty of Mathematics and Physics, University of Ljubljana, 1000 Ljubljana, Slovenia
K Slifer University of New Hampshire, Durham, New Hampshire 03824, USA
P Solvignon University of New Hampshire, Durham, New Hampshire 03824, USA
T Su Kent State University, Kent, Ohio 44240, USA
R Suleiman Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
L Tang Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
Y Tian Syracuse University, Syracuse, New York 13244, USA
W Tireman Northern Michigan University, Marquette, Michigan 49855, USA
F Tortorici INFN Sezione di Catania, Italy
Y Toyama Tohoku University, Sendai, Japan
K Uehara Tohoku University, Sendai, Japan
G M Urciuoli INFN, Rome, Italy
D Votaw Michigan State University, East Lansing, Michigan 48824, USA
J Williamson University of Glasgow, Glasgow, G12 8QQ Scotland, United Kingdom
B Wojtsekhowski Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
S Wood Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
Z H Ye Argonne National Laboratory, Lemont, Illinois 60439, USA Tsinghua University, Beijing, China
J Zhang University of Virginia, Charlottesville, Virginia 22904, USA
X Zheng University of Virginia, Charlottesville, Virginia 22904, USA

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High accuracy spectroscopy of 3- and 4-body Λ hypernuclei at Jefferson Lab

JLab E12-19-002 Experiment is planned to measure the Λ-binding energies of 3ΛH [Jπ = 1/2+ or 3/2+(T = 0)] and 4ΛH (1+) at JLab Hall C. The expected accuracy for the binding-energy measurement is |ΔBtotal Λ | ≃ 70 keV. The accurate spectroscopy for these light hypernuclei would shed light on the puzzle of the small binding energy and short lifetime of 3ΛH, and the chargesymmetry breaking in the ΛN interaction. We aim to perform the experiment in 2025.

Study of Λn FSI with Λ quasi-free productions on the 3H(e, e′K+)X reaction at JLab

Abstract. An nnΛ is a neutral baryon system with no charge. The study of the pure Λ-neutron system such as nnΛ gives us information on the Λn interaction. The nnΛ search experiment (E12-17-003) was performed at JLab Hall A in 2018. In this article, the Λn FSI was investigated by a shape analysis of the 3H(e, e′K+)X missing mass spectrum, and a preliminary result for the Λn FSI study is given.

Cross-section measurement of virtual photoproduction of iso-triplet three-body hypernucleus, Λnn

Missing-mass spectroscopy with the 3H(e, e′K+) reaction was carried out at Jefferson Lab’s (JLab) Hall A in Oct–Nov, 2018. The differential cross section for the 3H(γ∗, K+)Λnn was deduced at ω = Ee − Ee′ = 2.102 GeV and at the forward K+-scattering angle (0° ≤ θγ∗K ≤ 5°) in the laboratory frame. Given typical predicted energies and decay widths, which are (BΛ, Γ) = (−0.25, 0.8) and (−0.55, 4.7) MeV, the cross sections were found to be 11.2 ± 4.8(stat.)+4.1−2.1(sys.) and 18.1 ± 6.8(stat.)+4.2−2.9(sys.) nb/sr, respectively. The obtained result would impose a constraint for interaction models particularly between Λ and neutron by comparing to theoretical calculations.

Study of the Λ/Σ0 electroproduction in the low-Q2 region at JLab

We performed an experiment using tritium and hydrogen cryogenic gas targets at Thomas Jefferson National Accelerator Facility (JLab) in 2018 (E12-17-003)[1, 2]. In this article, we discuss the Λ/Σ0 hyperon electroproduction from hydrogen target. Elementary Λ/Σ0 hyperon production processes are important not only for an absolute mass scale calibration in our experiment, but also for the study of the electroproduction mechanisms themselves. In this article, we reported the results of the differential cross section for the p(e, e’K+)Λ/Σ0 reaction at Q2 ∼ 0.5 (GeV/c)2.

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.

Three-year experience with risedronate therapy for patients with an increased fracture risk: assessment of proximal femoral bone density and geometry by DXA

BACKGROUND AND OBJECTIVE

We previously reported that risedronate improved the structural parameters of the proximal femur, as well as lumbar spine and proximal femoral bone mineral density (BMD), after 1 year of therapy by suppressing bone resorption in patients with an increased risk of fracture. Our practice-based observational study was subsequently extended to determine whether these effects were enhanced, maintained or attenuated after 3 years.

METHODS

A total of 174 patients (nine men and 165 postmenopausal women) with a mean age of 67.8 years who had osteoporosis or osteopenia and clinical risk factors for fracture started risedronate therapy. The BMD of the lumbar spine and proximal femur, as well as proximal femoral structural parameters, were evaluated by dual-energy x-ray absorptiometry with advanced hip assessment (AHA) software at baseline and every year for 3 years.

RESULTS

Data were available for 107 patients at 1 year, 80 patients at 2 years and 74 patients at 3 years. Lumbar spine, total hip and femoral neck BMD and the cross-sectional area (CSA) of the proximal femur increased from baseline after 1 year with levels being maintained after 2-3 years. The cross-sectional moment of inertia (CSMI) of the proximal femur increased from baseline after 1 year and the increase was enhanced after 2 years with levels being maintained after 3 years. The femoral strength index (FSI) increased from baseline after 1 and 2 years and the increase was enhanced after 3 years. The increases in proximal femoral CSMI and FSI were greater than those of total hip and femoral neck BMD after 3 years of therapy.

CONCLUSION

The present study showed the effects of risedronate therapy for 3 years on the BMD of the lumbar spine and proximal femur, as well as on proximal femoral structure, in patients with an increased risk for fracture.

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.

Risedronate improves proximal femur bone density and geometry in patients with osteoporosis or osteopenia and clinical risk factors of fractures: a practice-based observational study

The purpose of this practice-based observational study was to clarify the acute effect of risedronate on proximal femur bone mineral density (BMD) and structural geometry in patients with an increased risk of fractures. One hundred sixty-four patients (7 men and 157 postmenopausal women; mean age, 69.2 years) with osteoporosis or osteopenia and clinical risk factors of fractures were analyzed. All these patients were treated with risedronate for 1 year. Urinary levels of cross-linked N-terminal telopeptide of type I collagen (NTX) were measured at baseline and 4 months after the start of treatment. BMD of the lumbar spine and proximal femur and structural geometric parameters of the proximal femur were evaluated by dual-energy X-ray absorptiometry with advanced hip assessment (AHA) software at baseline and every 4 months. Urinary NTX levels significantly decreased after 4 months of treatment. BMD of the femoral neck and total hip significantly increased after 4, 8, and 12 months of treatment. Cross-sectional moment of inertia (CSMI) and cross-sectional area significantly increased after 4, 8, and 12 months of treatment. An increase in CSMI was apparently greater than those of proximal femur BMD after 4 months of treatment. These results suggest the acute (4 months) and sustained (12 months) effect of risedronate on proximal femur structural geometry as well as BMD as a result of suppression of bone resorption in patients with an increased risk of fractures.

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.

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.

Progression of pneumoconiosis in coal miners after cessation of dust exposure: a longitudinal study based on periodic chest X-ray examinations in Hokkaido, Japan

BACKGROUND

The progression rate of pneumoconiosis in retired coal miners over ten years has not been studied in Japan.

METHODS

A retrospective longitudinal study was undertaken using chest X-rays of 1091 pneumoconiosis subjects in Hokkaido, Japan between 1985 and 2005.

RESULTS

The final numbers of subjects were 207 (19% of the entry) after 1 decade and 85 (8%) after 2 decades. Sixty-two percent of 207 subjects after 1 decade and 29% of 85 showed progression in 2 decades. Thirty-one percent of ILO category 1 and 55% of category 2 subjects showed progression to complicated pneumoconiosis after 1 decade, and 6% (4 of 64) of category 1 and 6% (5 of 77) of category 2 subjects progressed to complicated pneumoconiosis during 2 decades.

CONCLUSION

The progression of pneumoconiosis was observed after the cessation of dust exposure, especially during the first 10 years.

Urinary trypsin inhibitor improves viability of the liver in brain-dead rats

BACKGROUND/AIMS

The present study examined the effect of urinary trypsin inhibitor (UTI) on liver injury in hypotensive brain-dead rats.

METHODS

Brain death was induced by inflating a balloon catheter placed in the epidural space. UTI (100,000 units/kg/hour) was intravenously administered from 30 min until 6 hours after the induction of brain death. Systemic hemodynamics and hepatic tissue flow (HTF) were measured, and blood samples and hepatic tissue specimens for morphological examinations were obtained during the experiments.

RESULTS

The induction of brain death caused a 30% decrease in both mean arterial pressure and HTF, and an increase in the serum transaminase level in comparison with sham-operated rats. Brain death also increased the serum concentration of cytokine-induced neutrophil chemoattractant (CINC) (4.4-fold), as well as the number of CINC-positive cells (4.4-fold) and sequestered neutrophils in the sinusoids (3.1-fold). Post-treatment of brain-dead rats with UTI restored the HTF and reduced serum transaminase level. UTI decreased plasma CINC level and the number of neutrophils and CINC-positive cells in the sinusoids.

CONCLUSIONS

The results suggest that treatment with UTI after the establishment of brain death improved the viability of the liver in hypotensive brain-dead rats by inhibiting CINC production.

The advantage of Kakita's method with pancreaticojejunal anastomosis for pancreatic resection

In 1996, we reported the technical aspects of our new method for end-to-side pancreatojejunostomy (Kakita's method) that we performed in combination with the Whipple procedure without any complications related to failure in the anastomosis. In this chapter, we will introduce our technique in end-to-end style pancreatojejunal anastomosis with fewer anastomotic complications. The purpose of this study was to review Kakita's method with pancreatoduodenectomy. From April 1990 to December 2005, 324 consecutive cases of pancreatoduodenectomy were performed in the Department of Surgery at Kitasato University. In our institute, reconstruction in pancreatoduodenectomy is basically performed according to a modified Child's procedure. Our method is simple and can be applied wherever an end-to-side pancreatojejunal anastomosis is required. It consists of three steps: First, a drainage tube is inserted into the pancreatic duct. The second step, which is the unique aspect of our method, is an attachment of the jejunal wall and the cut surface of the pancreas using a single-layer suture technique. This allows us not only to reduce the number of sutures but also to eliminate some of the complicated manipulations required by other methods. The jejunal wall fully covers the cut surface of the pancreas, leaving no uncovered area between the wall and the pancreas. Third, a direct anastomosis between the pancreatic duct and the mucosal layer of the jejunal loop is applied. In our series, pancreatojejunal anastomotic leakage occurred only in 4 out of 324 patients, which was 1.23%. All patients were successfully treated with conservative therapy using drainage for an extended period postoperatively. The newly devised pancreatojejunostomy in our department is a simple, safe, and reliable procedure with excellent results.

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.

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.

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.

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.

Fortified preterm human milk for very low birth weight infants

We studied the nutritional effects of two types of human milk fortifiers for very low birth weight infants. These studies suggest that fortified human milk provides nutritional advantages for very low birth weight infants. However, providing calcium and phosphorus with supplementation is necessary for the improvement of bone density.

[Membranous septal aneurysm with aortic regurgitation: a case report]

A case of membranous septal aneurysm with aortic regurgitation (AR) in a 13-year-old male was reported. As AR was progressed rapidly in this case, aneurysmorrhaphy of membranous septal aneurysm and aortic valve plication were performed. The postoperative coarse was uneventful. It was considered that the course of AR was prolapse of aortic valve related with membranous septal aneurysm.

Serial P-31 MR spectroscopy after fructose infusion in patients with chronic hepatitis

Serial changes in phosphorus metabolites after intravenous administration of fructose were compared between five healthy volunteers and five patients with chronic hepatitis by means of phosphorus-31 magnetic resonance (MR) spectroscopy. P-31 spectra were obtained every 5 minutes after intravenous drip infusion of 20% fructose at a dose of 0.5 g/kg of body weight. In the healthy volunteers, phosphomonoesters (PME) increased to 338% +/- 76% of the preadministration value at 15-20 minutes. Inorganic phosphate (Pi) was depleted in the first 15 minutes, then rebounded to 260% +/- 67% of the initial value. beta-adenosine triphosphate decreased to less than 50% of its initial value and then gradually recovered. In patients with chronic hepatitis, the increase of PME at 15-20 minutes (151% +/- 49% of the preadministration value) was significantly less than that in healthy volunteers (P less than .05). In addition, the rebound of Pi at 35-40 minutes (126% +/- 42%) was significantly less than that in healthy volunteers (P less than .05). In conclusion, P-31 MR spectroscopy with fructose administration is valuable in the functional evaluation of diffuse liver diseases.

[A case of spontaneous regression of malignant lymphoma, complicated with miliary tuberculosis, liver dysfunction and pancytopenia]

An 82-year-old woman was admitted to Iwamizawa Rosai Hospital, Cardiovascular Medicine, for detailed examination of an aneurysm of abdominal aorta. CT scan revealed marked swelling of para-aortic lymph nodes which regressed spontaneously in three months. She was re-admitted to our hospital because of general malaise and gait disturbance. Her chest X-ray on the second admission revealed miliary disseminated shadows, which were confirmed to be tuberculous granuloma by lung biopsy. She was initially well controlled with anti-tuberculosis drugs, followed by severe liver dysfunction and pancytopenia, and died of respiratory and cardiac failure. At autopsy, wide-spread malignant lymphoma and miliary tuberculosis of the lung were found. The cause of liver dysfunction was strongly suspected to be due to infiltration of the lymphoma cells to portal triads of the liver. Hemophagocytosis found in the bone marrow, spleen and liver might be consistent with clinically so-called "hemophagocytic syndrome", causing pancytopenia, associated with infection.

[MR imaging of splenic masses]

It has been reported that MR imaging of the spleen is unsuccessful in detecting focal lesions because there is not a significant difference in relaxation times between most tumors and surrounding normal spleen. We reviewed the MR imaging of 15 patients (5 cysts, 2 abscesses, 1 hemangioma, 5 malignant lymphomas, 2 metastatic tumors). In all cases, the difference in signal intensities between splenic tissue and mass lesions permitted detection of splenic lesions on MR images. But, malignant lesions were less visible than benign lesions.

[A case of coronary artery bypass grafting with right gastroepiploic artery for right coronary artery obstruction associated with aortitis syndrome]

A case of a 66 year-old female with aortitis syndrome with right coronary arterial obstruction, was reported. The coronary arteriogram showed total occlusion of the right coronary artery (segment 2). On the aortogram, stenosis of the left common carotid artery, kinking and aneurysm of the descending thoracic aorta were revealed. Because she developed frequent attacks of effort angina and the descending thoracic aneurysm was small in diameter 38 mm, coronary bypass grafting to the right coronary artery was performed using the in situ right gastroepiploic artery. Postoperative course was not eventful and chest pain disappeared. In such cases, the right gastroepiploic artery is useful for coronary artery bypass grafting.

[A case report of A-C bypass surgery in coronary atherosclerosis with anomalous origin of left coronary artery]

Anomalous coronary artery originating from the aorta without complicated congenital cardiac anomaly is rare. We describe a case with the left coronary artery originating from the right sinus of Valsalva. Cardiac catheterization revealed a left coronary artery transverse between the aorta and the pulmonary artery. Severe atherosclerotic stenosis was present at segment 3 of the right coronary artery. Electrocardiogram and myocardial scintigraphy revealed that the angina occurred due to stenosis of the right coronary artery. We tried PTCA, but could not pass the catheter through the stenosis. After PTCA, he complained of anterior chest pain frequently, so we performed an aortocoronary bypass operation to the right coronary artery with saphenous vein graft. Postoperative course was not eventful and angina disappeared.

Head and neck reconstruction with pectoralis major myocutaneous flap: CT evaluation

Sixty-one CT scans in 20 patients who had undergone head and neck reconstructive surgery using a pectoralis major myocutaneous (PM-MC) flap were retrospectively evaluated to assess the usefulness of Ct in the follow-up of these patients. The normal CT findings in patients with PM-MC flaps are described. Of 13 cases with tumor recurrence, CT examination correctly detected recurrent masses in all cases, including 3 in which there was no clinical sign of recurrence. Postoperative masses mimicking tumor recurrence included deformed breast tissue, hematomas, lymphoceles, and abscesses. Computed tomography was of great value in the detection of tumor recurrence, but careful interpretation is required because a postoperative complication or anatomic alteration may lead to the erroneous diagnosis of tumor recurrence.

[A case report of mycotic false aortic aneurysm associated with aortic regurgitation]

The patient was 63-year-old man, who underwent patch closure of VSP 37 days after onset. LVAD was required for weaning from CPB. Mediastinitis occurred after LVAD was removed. The mediastinum was irrigated using diluted antibiotics through the retrosternal drain. He discharged on 79th day postoperatively. False aortic aneurysm and marked AR was pointed out by cineangiography and enhanced CT scan two years after operation. AVR was performed through right thoracotomy, because false aortic aneurysm invaded the sternum. The aneurysmal wall was repaired with patch. Postoperatively, peritoneal dialysis was performed for two days. Flail chest made difficult weaning from the respirator. He died 11 days postoperatively due to respiratory failure. There remains the possibility that mediastinitis resulted in false aortic aneurysm and AR. It was esseutial to remove the foreign materials placed on the aorta for eradication of infection.

Nuclear DNA content, cytomorphologic features and clinical characteristics of small cell carcinoma of the lung

The relationship between the cytomorphologic features, the nuclear DNA patterns and the clinical prognosis of patients with small cell carcinoma of the lung was studied. In cases in the long-survival group (greater than or equal to 24 months), bronchial brushing smears contained a relatively high frequency of nuclei with large, irregular shapes and finely granular chromatin patterns, in comparison with patients in the short-survival group (less than or equal to 9 months); the correlation was not statistically significant, however. The incidence of cells with round or oval nuclei and finely granular chromatin patterns was higher in patients whose cells had hyperdiploid DNA patterns than for patients whose cells had near-diploid patterns; again, the difference was not statistically significant. Patients whose tumor cells had hyperdiploid DNA patterns had significantly shorter survival times than did patients whose tumor cells had near-diploid patterns. These results indicate that (1) judging the nuclear DNA pattern from the cytomorphologic features of small cell carcinoma is unreliable and (2) the nuclear DNA patterns are related to the clinical prognosis of patients with small cell carcinoma of the lung.