Evolution of beam distribution in crossing a Walkinshaw resonance.

The third-integer coupling resonance at ν(x)-2ν(z)=ℓ, known as the Walkinshaw resonance, is important in high-power accelerators. We find that, when the betatron tunes ramp through a Walkinshaw resonance the fractional emittance growth (FEG) is a universal function of the effective resonance strength: G(1,-2,ℓ)√[ε(xi)]|Δ(ν(x)-2ν(z))/Δn|(-1/2), where G(1,-2,ℓ) is the resonance strength; ε(xi) and ε(zi) are the initial horizontal and vertical emittances, respectively; and |Δ(ν(x)-2ν(z))/Δn| is the resonance crossing rate per revolution. At large effective resonance strengths, the FEG reaches an asymptotic maximum value (FEG)(max)~2ε(xi)/ε(zi) for ε(xi)>>1/2ε(zi) or ε(zi)/(2ε(xi)) for ε(xi)<<1/2ε(zi). There is little emittance exchange at ε(xi)=1/2ε(z), which can be used to minimize emittance growth in crossing a Walkinshaw resonance.

Los probioticos tienen eficacia clinica, microbiologica e inmunolólica en la diarrea infecciosa aguda / Probiotics have clinical efficacy, microbiological and immunological acute infectious diarrhea

La diarrea infecciosa aguda es una causa importante de morbilidad en la infancia y responsable de unacarga económica para las familias. Es este estudio se evaluó las características clínicas, microbiológicas,inmunológicas y efectos de los probióticos en diarrea infecciosa aguda.

Acute gastroenteritis caused by multiple enteric pathogens in children.

Of 303 children hospitalized with acute non-bloody, non-mucoid diarrhoea, 69 (22.8%) had polymicrobial infection, including 52 (17.2%) multiple viral infection and 17 (5.6%) viral and bacterial co-infection. Rotavirus had the most important role in both categories; thus the control of rotavirus infection is crucial for maintaining children's health in Taiwan.

Quadruple-bend achromatic low emittance lattice studies.

A quadruple-bend achromatic (QBA) cell, defined as a supercell made of two double-bend cells with different outer and inner dipole bend angles, is found to provide a factor of 2 in lowering the beam emittance relative to the more conventional double-bend achromat. The ratio of bending angles of the inner dipoles to that of the outer dipoles is numerically found to be about 1.5-1.6 for an optimal low beam emittance in the isomagnetic condition. The QBA lattice provides an advantage over the double-bend achromat or the double-bend nonachromat in performance by providing a small natural beam emittance and some zero-dispersion straight sections. A lattice with 12 QBA cells and a preliminary dynamic aperture study serves as an example.

Comparison of the effect of a cornstarch thickened formula and strengthened regular formula on regurgitation, gastric emptying and weight gain in infantile regurgitation.

The purpose of this study was to evaluate the efficacy of a specially selected cornstarch-supplemented formula on clinical symptoms, gastric emptying and weight gain in infants with regurgitation. We performed a prospective randomised trial evaluating the therapeutic efficacy of two different formula feedings (cornstarch-thickened formula, group A; 25% strengthened formula, group B) in 81 young infants with regurgitation/vomiting > or = 3 times/day. A Tc-99 m milk scintigraphy was performed at inclusion and after 2 months to quantify gastric emptying time; all studied infants underwent a 2-month period of clinical follow-up evaluating regurgitation and body weight gain. At inclusion, group A and B had a similar age and weight. After the 2-month period of intervention, regurgitation and vomiting had both greater decrease (both P < 0.001 at 1 and 2 months) in group A (from a score of 4.19 +/- 1.71 to 0.93 +/- 0.42) than in group B (from a score of 4.15 +/- 1.68 to 2.89 +/- 1.16). Non-regurgitation symptoms (irritability, cough, choking, night-waking) decreased (P = 0.045 at 1 month and 0.017 at 2 months) in group A (from a score of 18 at baseline to 3 after 8 weeks) as compared to group B (from a score of 18 at baseline to 11 after 8 weeks). Weight increased more in group A (29.1 +/- 3.9 g/day over 8 weeks) versus group B (23.6 +/- 3.5 g/day over 8 weeks) (P < 0.01 at 1 and 2 months) Gastric emptying improved significantly in group A as compared with group B (all P < 0.001 for T1/2, and residual volume at 60 and 90 min). Ingested feeding volume was significantly larger in the group receiving cornstarch-thickened formula, both at 4 weeks (109.4 +/- 24.5 vs. 98.5 +/- 23.6 mL/meal) (P: 0.042) and at 8 weeks (137.6 +/- 27.9 vs. 115.7 +/- 26.5 mL/meal) (P < 0.001). Cornstarch-thickened formula feeding decreases the frequency of regurgitation/vomiting, provides better body weight gain and has an accelerated gastric emptying in comparison to a 25% strengthened regular formula in infants with regurgitation.

Non-traumatic colon perforation in children: a 10-year review.

Colon perforation is an abdominal surgical emergency in the pediatric population, but is seldom reported when occurring from non-traumatic causes in children beyond the neonate. The goal of this study was to identify the clinical characteristics, management, and outcomes of non-traumatic colon perforation in children. Medical records for the 10-year period from September 1994 to September 2004 were reviewed for children beyond the neonate with non-traumatic colon perforation. Data gathered included age, gender, symptoms, duration of symptoms, physical findings, and length of postoperative hospital stay. Diagnostic information included laboratory data, radiographic imaging, and operative findings. Forty-four patients with non-traumatic colon perforation were recruited into this study. The mean age was 2.22 +/- 1.87 years; 91.4% of cases were younger than 5 years old. The most common presenting symptom was fever (97.7%); the most common sign was abdominal distention (93.1%). The mean duration of symptoms prior to admission was 6.19 days. Pneumoperitoneum was presented in 86.3% of patients by plain abdominal radiograph. Ascending and transverse colon were the most common perforation sites. Non-typhoid salmonella was the leading pathogen isolated, causing 20.4% of episodes. One case died due to Clostridium speticum infection. Non-traumatic colon perforation most commonly affects children younger than 5 years of age. It may be secondary to infection, especially non-typhoid salmonella. Plain abdominal radiograph can be an adjuvant tool for the high index of suspicion for colon perforation in children with abdominal distention and history of fever or diarrhea for more than 5 days.

Expression of adhesion molecules on T lymphocytes in young children and infants--a comparative study using whole blood lysis or density gradient separation.

We investigated the use of two sample preparation techniques (whole blood lysis [WBL], and Ficoll-Hypaque density separation [FDS]) for flow cytometric estimation of adhesion molecule (CD54, CD62L and CD11b) expression on T lymphocytes from children less than 2 years old, comparing the results with normal adult controls. Using WBL methods, young children had lower percentages of CD3+/CD54+ and CD3+/CD11b+ lymphocytes, but not of CD3+/CD62L+ lymphocytes than adult controls. FDS was associated with significantly higher percentages of CD3+/CD62L+ and CD3+/CD11b+ lymphocytes in young children and adults alike, while the percentages of CD3+/CD54+ cells from adults was not affected by FDS. The percent expression of CD54, CD62L, and CD11b on T cells from both children and adults were significantly higher following FDS, with a greater increase in CD11b expression on T cells from young children, reaching adult levels. The mean fluorescence intensity (MFI) of CD62L on T cells from young children, which was lower than that of adults using WBL preparation, was significantly higher following FDS, reaching adult levels. The higher levels of adhesion molecule expression associated with FDS did not result from T-cell activation, as assessed by CD69, CD25, and HLA-DR expression. Thus, adhesion molecule expression on T lymphocytes from young children is more sensitive to modification by isolation procedures than that on adult T cells. Caution should therefore be exercised in interpreting adhesion molecule expression data on T cells from children.

Congenital diaphragmatic hernia diagnosed by magnetic resonance imagine in late infancy: Report of one case.

We report the magnetic resonance imagine (MRI) findings of an 11-month-old baby with delay onset of congenital diaphragmatic hernia (CDH). The capability of visualizing diaphragmatic discontinuity, connecting bowel segments between abdomen and chest are clearly demonstrated. The various techniques of diagnosing diaphragmatic hernia are described and we emphasize the potential usefulness of MRI in CDH.

Interleukin-15 enhances CD4(+) CD45RA(+) expression on umbilical cord blood mononuclear cells.

The reduced incidence of graft-vs.-host disease following umbilical cord blood (CB) transplantation may be related to the functional immaturity of newborn T cells expressing mainly the naive CD45RA phenotype. Expansion of CD4(+) CD45RA(+) T cells using cytokines may benefit neonates and infants with human immunodeficiency virus (HIV) infection, as a preferential decline in CD4(+) CD45RA(+) cells has been noted as HIV disease progresses. The aim of the study was to investigate the effect of interleukin (IL)-15, a novel cytokine similar to IL-2 in biological activities, on CD45RA/RO expression and apoptosis in umbilical cord blood (CB) and adult peripheral blood (APB) mononuclear cells (MNCs). Prior to culture, CB MNCs contained a greater number of CD4(+) CD45RA(+) cells and fewer CD4(+) CD45RO(+) cells than did APB MNCs. When incubated with RPMI-1640 containing 10% fetal calf serum for 7 days, the percentage of CD45RA(+) cells within CD4(+) T cells (%CD45RA(+)/CD4(+)) significantly decreased compared to that of fresh CB MNCs. IL-15 exerted a dose-dependent increase of %CD45RA(+)/CD4(+) and a corresponding decrease of %CD45RO(+)/CD4(+) in CB MNCs, an effect not observed with APB MNCs treated with IL-15. The percentages of CD45RA(+) and CD45RO(+) expression within CD8(+) cells, however, were not influenced by IL-15, in either CB or APB MNCs. A greater number of CB MNCs underwent apoptosis than did APB MNCs after 7 days of culture in RPMI-1640 containing 10% fetal calf serum. IL-15 did not inhibit apoptosis but induced proliferation comparable to that achieved in APB MNCs. The ability of IL-15 to preferentially enhance the proliferation of CD4(+) CD45RA(+) cells in CB MNCs suggests a role for immunomodulative therapy in HIV-infected newborns and infants.

Phenotypic changes of T-lymphocyte subsets induced by interleukin-12 and interleukin-15 in umbilical cord vs. adult peripheral blood mononuclear cells.

The decreased incidence of graft-vs.-host disease found following umbilical cord blood (CB) transplantation, and the increased susceptibility of newborns to infections, have been attributed, in part, to functional and phenotypic immaturity of neonatal T cells. We investigated the phenotypic changes of CB T cells induced by two immunoregulary cytokines, interleukin (IL)-12 and IL-15, alone or in combination. Adult peripheral blood (APB) mononuclear cells (MNCs) were also tested for comparison. Prior to culture, the percentages of CD3+ CD8+, CD3+ CD25+, and CD3+ CD56+ cells were significantly lower in CB MNCs than in APB MNCs. IL-15, but not IL-12, significantly increased CD3+ CD8+ expression among the CB MNCs after 1 week of culture. Combining IL-12 and IL-15, however, resulted in decreased CB CD3+ CD8+ expression compared with IL-15 alone. The percentage of CD3+ CD25+ cells in CB MNCs spontaneously increased in the absence of cytokines, while that of CD3+ CD56+ cells in CB MNCs could not be enhanced with cytokines. In contrast, the percentages of CD3+ CD25+ and CD3+ CD56+ cells among the APB MNCs could be increased with IL-12, IL-15, and further with IL-12 and IL-15 combined. Thus, different patterns of T-cell subset changes were demonstrated between CB MNCs and APB MNCs in response to IL-12 and/or IL-15. These data may serve as a foundation for using cytokine therapy in newborns and children receiving CB transplants.

Sonographic evaluation of cellulitis in children.

Within a 3 year period from July 1996 to July 1999, a total of 105 children with clinical diagnosis of cellulitis were evaluated by ultrasonography. Eighty-six children (age range, 17 days to 15 years) fulfilling the sonographic criteria for diagnosis of cellulitis were enrolled into the study. The sonographic features were used to correlate with clinical symptoms and their duration, the peripheral leukocyte count, and the serum C-reactive protein level. Pus aspiration for immediate microscopic and later bacteriologic studies was carried out under sonographic guidance. Ultrasonographic features of cellulitis included subcutaneous tissue thickening without distortion and pus (25 cases, 29%), distortion of subcutaneous tissue without pus accumulation (26 cases, 30%), distortion of subcutaneous tissue with pus accumulation (19 cases, 23%), and distortion of tissue with abscess formation (16 cases, 18%). The presence of sonographic features of tissue distortion with or without pus accumulation, including abscess formation in children with cellulitis, correlated with a longer duration of symptoms (greater than 4 days), the presence of high-grade fever, higher peripheral leukocyte count, and higher serum C-reactive protein levels. Those patients who underwent sonographically guided aspiration or surgical intervention showed a shorter hospital stay and fever duration than those without such aspiration. Our results indicated that ultrasonography is of great value in managing cellulitis by providing information regarding the progression of inflammation. Sonographically guided aspiration of pus may be a treatment of choice, as it may decrease the need for operation.

Sonographic evaluation of the pancreatic duct in normal children and children with pancreatitis.

We investigated the diameter of pancreatic duct using ultrasonography in 51 children with pancreatitis and age-matched healthy control children over a 5 year period. The diameters of pancreatic duct and pancreatic body were measured simultaneously by sonography. The mean ages of children with acute pancreatitis and chronic pancreatitis were 9.7 +/- 3.9 and 10.3 +/- 3.1 years, respectively (range, 1 to 8 years). The mean age of normal children was 9.6 +/- 5.3 years. A significant difference was found in diameter of the pancreatic duct between children with acute and chronic pancreatitis versus that of age-matched control. In addition, a significant difference in diameter of the pancreatic body was found between children with acute pancreatitis and age-matched controls, but there was no marked difference in diameter of the pancreatic body between normal persons and those with chronic pancreatitis. The mean diameters of the pancreatic duct in acute pancreatitis and chronic pancreatitis were 2.34 +/- 0.47 mm and 2.84 +/- 0.67 mm, respectively, which was greater than that of normal children (1.65 +/- 0.45 mm). Pancreatic ducts with diameters greater than 1.5 mm in children between 1 and 6 years, greater than 1.9 mm at ages 7 to 12 years, or greater than 2.2 mm at ages 13 to 18 years were significantly associated with the presence of acute pancreatitis. Thirty-two patients, including 25 with acute pancreatitis and 7 with chronic pancreatitis, underwent follow-up measurement of pancreatic duct and serum lipase examination on at least three occasions. A good correlation between the diameter of pancreatic duct and serum lipase level was found. Thus, ultrasonography of the pancreatic duct is valuable in diagnosis and monitoring of pancreatitis in children.

The effect of interleukin-12 and interleukin-15 on CD69 expression of T-lymphocytes and natural killer cells from umbilical cord blood.

We investigated the effect of two immunoregulatory cytokines interleukin-12 (IL-12) and IL-15, alone or in combination, on CD69 expression of mononuclear cells (MNCs) obtained from umbilical cord blood (CB) and adult peripheral blood (APB). We established that (1) CD3/69, but not CD16/69, expression on CB MNCs could be increased with IL-12, IL-15 or both in 18-hour cultures, but to a lesser degree compared to that on corresponding APB MNCs, (2) CD3/69 expression on CB MNCs was significantly increased after 1 week's culture with IL-12, especially with IL-15, exceeding that on APB MNCs similarly activated and (3) CD16/69 expression on CB MNCs, but not APB MNCs, was greatly increased after 1 week's culture with IL-15. The combination of IL-12 + IL-15 resulted in greater CB CD3/69 expression than individual cytokines, while producing less of an effect on CD16/CD69 expression as compared to IL-15 alone. The results of our study indicate that neonatal T and NK cells readily respond to cytokine stimulation by upregulating CD69 expression, with a greater effect achieved using IL-15 compared to IL-12.

Effect of interleukin-15 and Flt3-ligand on natural killer cell expansion and activation: umbilical cord vs. adult peripheral blood mononuclear cells.

Expansion and activation of cord blood (CB) natural killer (NK) cells by cytokines might greatly benefit patients undergoing stem cell transplantation by increasing resistance against viral infections and providing graft-vs.-leukemia (GVL) effects through enhanced cytolytic abilities. We tested the ability of a recently cloned stem cell factor, Flt3-ligand (Flt3L), in combination with interleukin-15 (IL-15), to stimulate CB mononuclear cells (MNCs) to proliferate and differentiate into NK cells, in comparison with adult peripheral blood (APB) MNCs. Unstimulated CB MNCs had low NK and lymphokine-activated killer (LAK) activity compared with APB MNCs. A similar dose-dependent increase in NK and LAK activity and CD16/56 expression was found with IL-15 in CB and APB MNCs after 10 days of culture. The NK cytotoxicity (against K562 cells) of IL-15-treated CB MNCs was lower than that of corresponding APB MNCs, while IL-15-induced LAK activity (against Daudi cells) of CB MNCs was comparable to that of corresponding APB MNCs. IL-15 resulted in greater CD16/56 expression in CB MNCs compared with APB MNCs after 10 days of culture. Flt3L, alone or in combination with IL-15, had little effect on CD16/56 expression and cytotoxicity. Cytotoxic activities and CD16/56 expression did not alter after CD34 depletion of CB MNCs. We therefore concluded that CB NK cells could be greatly activated and expanded with IL-15, but not with Flt3L. The greater expression of CD16/56 induced by IL-15 in CB MNCs may originate from non-CD34+ NK progenitor cells.

Hepatobiliary involvement of Henoch-Schönlein purpura in children.

Hepatobiliary manifestation and its evolution in children with Henoch-Schönlein purpura (HSP) had been scarcely reported. Over a ten-year period between June 1988 and November 1998, medical charts of 225 children with the diagnosis of HSP encountered at Chang Gung Children's Hospital were reviewed. Those with the evidence of hepatobiliary involvement were enrolled in the study. The patients with hepatobiliary involvement were defined by having an elevated serum alanine transaminase (ALT) or gamma-glutamyl transferase (GGT), and the presence of abnormal sonographic findings involving liver, biliary system, and gallbladder. The patients included 9 boys and 11 girls with range of age from 3 to 11 years. The mean age of these patients was 6.5 +/- 3.7 years. Preceding upper respiratory tract infection was common in these patients (35%). The main clinical manifestation were distinct from typical abdominal symptoms of HSP, and included right upper quadrant pain (80%), nausea (45%), lethargy (20%), and vomiting (15%). Elevated serum ALT was noted in 15 cases (75%) and GGT in 6 cases (30%). Abdominal ultrasonography revealed hepatomegaly (15/20, 75%), and gallbladder wall thickening (5/20, 25%). No specific laboratory parameters were correlated with the hepatobiliary manifestation of HSP. Fourteen children (70%) received steroid therapy and disappearance of symptoms and sonographic resolution of hepatobiliary lesion was noted within 3-7 days of steroid therapy. All patients recovered completely except for one patient with hepatobiliary recurrence manifested as purpuric rash, abdominal pain, elevated GGT, and gallbladder wall thickening during 2-year follow-up.

Papillary cystic neoplasm of the pancreas in children: report of three cases.

Papillary cystic neoplasm of the pancreas is very rare in children. There were only 35 pediatric cases reported in the literature. We herein three children who had papillary cystic neoplasm of pancreas. They were female teenagers, and were pathologically diagnosed. The major presenting symptoms were abdominal pain and abdominal mass. Serum tumor markers of these patients showed normal results. A CT scan of these patients showed that this tumor was of pancreatic origin. These 3 tumors were localized to head, body, and tail, respectively. The mean maximal diameter of these tumors was 11.3 +/- 3 cm. Sonography and CT examination showed that the tumor was a heterogeneous mass with solid and cystic components. Angiography of this tumor showed a hypervascular mass with blood supply mainly from pancreatic branch of splenic artery. They all underwent tumor resection. All tumors contained some degree of internal hemorrhage or cystic degeneration and all were well encapsulated. Histologically, tumor cells generally showed solid and pseudopapillary growth around the fibrovascular stalks. No metastasis, mortality or recurrence was noted during follow-ups. In conclusion, CT scan helps to make a prospective diagnosis of papillary cystic neoplasm of pancreas. Our study confirmed that a papillary neoplasm of the pancreas is a low-grade malignant tumor. Surgical resection of the tumor is the mainstay of effective management.

Sonographic features related to volvulus in neonatal intestinal malrotation.

This 3 year prospective study evaluated the sensitivity and specificity of abdominal ultrasonography and color Doppler ultrasonography in 31 neonates with suspected malrotation or malrotation with volvulus. Water instillation was used to detect duodenal dilatation, edema, and malrotated bowels. Twenty patients with ultrasonographic characteristics of inversion of the superior mesenteric artery and superior mesenteric vein were later surgically proved to have malrotation. Nine of these 20 patients also had volvulus. Sonographic features suggestive of volvulus included duodenal dilation with tapering configuration (8 of 9 cases, 89%), fixed midline bowel (8 of 9 cases, 89%), whirlpool sign (8 of 9 cases, 89%), and dilation of the distal superior mesenteric vein (5 of 5 cases, 100%). The sensitivity and specificity of duodenal dilation with tapering configuration for detecting volvulus were 89% and 92%, respectively; of fixed midline bowel, 89% and 92%; of whirlpool sign, 89% and 92%; and of dilation of distal superior mesenteric vein, 56% and 73%. The results of this study indicate that ultrasonographic features of inversion of the superior mesenteric artery and superior mesenteric vein could aid in the diagnosis of malrotation, and certain sonographic features can also be used to evaluate volvulus, a condition requiring emergent operation.

Different articular outcomes of Still's disease in Chinese children and adults.

The clinical manifestations, treatment and course, and articular outcomes of 24 children with juvenile-onset Still's disease (JOSD) and 21 adults with adult-onset Still's disease (AOSD) were compared retrospectively. There was no significant difference in the initial clinical and laboratory manifestations except that more adults presented with a sore throat (81% vs. 46%, p = 0.03). Although serum ferritin was almost always elevated in both diseases, adults had significantly higher serum ferritin concentrations compared with those of children. Steroid treatment was required in 71% of children and 52% of adults, while disease-modifying antirheumatic drugs were used in 42% of children and 24% of adults during the course. Chronic arthritis (>6 months) occurred in comparable proportions of patients with JOSD and AOSD (46% vs 38%, p = 0.82), irrespective of the disease pattern (monocyclic or polycyclic). However, severe deforming arthritis with marked functional limitation occurred only in JOSD, particularly with polyarthritis at disease onset (more than five affected joints). In contrast, AOSD patients with chronic arthritis had a favourable functional outcome at the end of the follow-up. Our study suggested different articular outcomes of Still's disease in Chinese children and adults.

Factors associated with intestinal perforation in children's non-typhi Salmonella toxic megacolon.

BACKGROUND: To evaluate the risk factors for intestinal perforation in children with toxic megacolon caused by non-typhi Salmonella infection. METHODS: During an 11-year period we reviewed the records of children treated for non-typhi Salmonella infection. All of the subjects had positive stool culture for non-typhi Salmonella and were treated with intravenous ceftriaxone during hospitalization. Clinical data reviewed included demographic features, clinical manifestations, laboratory findings, radiologic findings, microbiology, therapeutic effect of hydration and rectal tube placement and the operative findings. Patients with toxic megacolon were defined as those having toxic appearance, diarrhea, high fever (>39 degrees C) and marked colon dilatation with maximal diameter > 1.5 times the width of the vertebra body of the first lumbar spine (L1-VB). To define the risk factors for patients with toxic megacolon complicated by intestinal perforation, patients were divided into two groups for analysis: P group, those complicated with intestinal perforation; and NP group, those without intestinal perforation. Differences in age, sex, severity of diarrhea, duration of fever, hemogram and its differential, culture, stool analysis, serum C-reactive protein (CRP), electrolytes, maximal colon diameter, medical therapy and timing of rectal tube insertion between the two groups were analyzed. Statistical analyses were conducted with chi square tests and multiple logistic regression. RESULTS: A total of 75 patients (P group, 27 patients; NP group, 48 patients) ages 4 months to 6 years were evaluated. With chi square analysis 7 variables were found to be significantly associated with intestinal perforation: age >1 year; fever >5 days; ratio of immature to total neutrophils >20%; serum CRP >200 mg/l; colon diameter >2.5 times the width of L1-VB; inadequate early hydration; and delay in rectal tube insertion. With multivariate analysis age >1 year, serum CRP >200 mg/l and colon diameter >2.5 times of width of L1-VB, inadequate early hydration and delay in rectal tube insertion were the most significant factors associated with intestinal perforation. CONCLUSION: Identification of patients with toxic megacolon associated with non-typhi Salmonella infection at risk for further intestinal perforation is possible. Early effective fluid resuscitation and rectal tube insertion may be helpful to prevent the occurrence of intestinal perforation.