Usefulness of virtual touch tissue quantification for predicting the presence of esophageal varices in patients with liver cirrhosis.

BACKGROUND AND AIM: Measuring the hepatic venous pressure gradient (HVPG) is an established technique to detect increased portal pressure and predict the presence of esophageal varices (EVs); however, the risk of the test is greater than the information it provides. This study aimed to clarify the usefulness of virtual touch tissue quantification (VTQ), which assesses liver stiffness, in predicting the presence of EVs in patients with liver cirrhosis by comparing it with HVPG. METHODS: Two hundred seventeen patients with liver cirrhosis underwent VTQ, HVPG measurement, and upper endoscopy. Patients were divided into three groups: group V, hepatitis C virus liver cirrhosis (n = 40); group A, alcoholic liver cirrhosis (n = 116); and group N, other liver cirrhosis (n = 61). In each group, we performed linear regression analysis of VTQ and HVPG data. The accuracy of VTQ and HVPG measurement in predicting the presence of EVs and high-risk EVs (EV category F2 and F3) was assessed by area under the receiver operating characteristic curve (AUROC). RESULTS: VTQ was significantly correlated with the HVPG in the whole patients and in each group, and both VTQ and HVPG values were significantly higher in patients with EVs and high-risk EVs than in those without. The AUROC for the presence of EVs for VTQ was 0.76 in the whole sample, 0.76 in group V, 0.79 in group A, and 0.67 in group N; and for HVPG, 0.92, 0.94, 0.93, and 0.88, respectively. For VTQ, the AUROC for the presence of high-risk EVs was 0.78 in the whole sample, 0.78 in group V, 0.73 in group A, and 0.73 in group N; and for HVPG, it was 0.85, 0.82, 0.85, and 0.82, respectively. CONCLUSION: VTQ was reliable at predicting the presence of EVs and high-risk EVs. Therefore, we propose that VTQ is a useful, noninvasive tool for predicting the presence of EVs in daily medical care.

Clinical features of 35 Down syndrome patients with transient abnormal myelopoiesis at a single institution.

Transient abnormal myelopoiesis (TAM) is a unique clonal myeloproliferation characterized by immature megakaryoblasts that occurs in 5-10% of neonates with Down syndrome (DS). Although TAM regresses spontaneously in most patients, approximately 20% of TAM cases result in early death, and approximately 20% of survivors develop acute megakaryoblastic leukemia (AMKL). We retrospectively reviewed records of 35 DS patients with TAM to determine the correlation between clinical characteristics and blast percentage. Thirteen of the 35 patients were classified as low blast percentage TAM (LBP-TAM), defined as TAM with a peak peripheral blast percentage ≤ 10%. Although no patient with LBP-TAM experienced systemic edema, disseminated intravascular coagulation, or early death, eight patients had elevated direct bilirubin levels (> 2 mg/dl) and one developed AMKL. All patients with LBP-TAM had serum markers of liver fibrosis that exceeded the normal limits, and two patients underwent liver biopsy to clarify the etiology of pathological jaundice. Taken together, our results suggest that patients with LBP-TAM may be at risk of liver fibrosis and liver failure, similarly to patients with classical TAM. Although these patients generally have a good prognosis, they should be carefully monitored for potential development of liver disease and leukemia.

Flux Growth and Magnetic Properties of Helimagnetic Hexagonal Ferrite Ba(Fe1-x Sc x )12O19 Single Crystals.

Fabricating large, high-crystalline-quality single-crystal samples of hexagonal ferrite Ba(Fe1-x Sc x )12O19 is the first important step to elucidating its helimagnetic structure and developing it for further applications. In this study, single crystals of Ba(Fe1-x Sc x )12O19 of various Sc concentrations x were successfully grown by the spontaneous crystallization method using Na2O-Fe2O3 flux. We determined the optimal starting composition of reagents for Ba(Fe1-x Sc x )12O19 growth as a function of x. In situ monitoring of the crystal nucleus generation accelerated the success of crystal growth. The obtained crystals comprised black and lamellate structures with a size of 13 mm × 8 mm × 2 mm and a surface of {001} orientation. X-ray diffraction and elemental analysis revealed that the obtained crystals were composed of single-phase Ba(Fe1-x Sc x )12O19 of high crystalline quality. The lattice constants a and c increased linearly with increasing x, thereby following Vegard's law. The temperature dependence of magnetization and the magnetization curves at 77 K of the x = 0.128 crystal exhibited behavior characteristics of helimagnetism. Neutron diffraction measurements of the x = 0.128 crystal exhibited magnetic satellite reflection peaks below 211 K, providing evidence that Ba(Fe1-x Sc x )12O19 behaves as a helimagnetic material.

Prevalence and Risk Factor for Antibiotic-resistant Escherichia coli Colonization at Birth in Premature Infants: A Prospective Cohort Study.

BACKGROUND: Escherichia coli causes neonatal early-onset sepsis (EOS) that is associated with high mortality and increasing antibiotic resistance. Thus, we estimated the prevalence, antibiotic susceptibility and risk factors for colonization of E. coli in premature infants at birth and characterized the pathogenicity of the isolates. METHODS: A prospective surveillance study was conducted at three Japanese perinatal centers between August 2014 and February 2017. Infants weighing <2 kg and/or at gestational age <35 weeks at birth were enrolled. We screened the mothers and neonates for E. coli colonization. Pulsed-field gel electrophoresis was used to analyze the relatedness between the maternal and neonatal isolates. Virulence factors for the isolates were determined using polymerase chain reaction. RESULTS: We enrolled 421 premature infants born to 382 mothers. The rate of colonization in mothers was 47.6%, comprising 5.9% extended-spectrum beta-lactamase-producing E. coli (ESBL-E) and 20.0% ampicillin-resistant strains. Ten (2.4%) infants exhibited colonization; ESBL-E and ampicillin-resistant strains colonized three and four infants, respectively. Three antibiotic-resistant, strain-positive infants developed EOS. Pulsed-field gel electrophoresis revealed vertical transmission of bacteria in four infants. Multivariate logistic regression analysis revealed that ESBL-E-positive mothers [odds ratio (OR), 19.2; 95% confidence interval (CI), 2.5-145.7)] and vaginal delivery (OR, 9.4; 95% CI, 1.7-50.7) were risk factors for neonatal colonization. The infant isolates possessed numerous virulence factors. CONCLUSIONS: Although the prevalence of E. coli-colonized premature infants at birth was low, the rate of antibiotic resistance and the attack rate for EOS were high. Infants with ESBL-E positive mothers should be closely monitored for EOS.

Flash Imaging Used in the Post-vascular Phase of Contrast-Enhanced Ultrasonography is Useful for Assessing the Progression in Patients with Hepatitis C Virus-Related Liver Disease.

Sonazoid is a commonly used contrast agent for characterizing liver tumors in ultrasonography (US). We performed flash imaging in the post-vascular phase of contrast-enhanced US (CEUS) to investigate associations between collapse of Sonazoid microbubbles (MB) and progression of liver disease. This study enrolled 409 patients (205 men, 204 women) with hepatitis C virus-related liver disease (CLD) between 2007 and 2017 (mean age 60 ± 14 y; range 20-90 y). In the post-vascular phase, 10 min after administering Sonazoid, flash imaging was performed to burst MB in the liver parenchyma; the range of bubble destruction was measured from the surface of the liver. The range of bubble destruction, stage of fibrosis, shear wave velocity (Vs), serologic markers and fibrosis-4 (FIB4) index were analyzed in 259 patients who underwent liver biopsy. Fibrosis stage was F0-1 in 108 patients, F2 in 73, F3 in 38 and F4 in 40. In 150 patients with cirrhosis, diagnosis was made based on imaging findings. The range of bubble destruction was 42.0 ± 10.4 mm in F0-1 patients, 42.9 ± 13.2 mm in F2, 51.5 ± 15.9 mm in F3 and 55.4 ± 17.3 mm in F4 and was significantly increased according to progression of fibrosis staging. The range of bubble destruction was positively correlated with Vs (r = 0.34; p < 0.01), total bilirubin (r = 0.25; p < 0.01) and FIB4 index (r = 0.38; p < 0.01). In contrast, the range of bubble destruction was negatively correlated with serum levels of albumin (r = -0.34; p < 0.01), platelet count (r = -0.35; p < 0.01) and prothrombin time (r = -0.36; p < 0.01). The results indicated that flash imaging in the post-vascular phase of CEUS was a non-invasive assessment and could predict disease progression in patients with CLD.

Hepatic arterialization can predict the development of collateral veins in patients with HCV-related liver disease.

PURPOSE: Arrival time parametric imaging (At-PI) using contrast-enhanced ultrasonography (CEUS) is a procedure for evaluating liver disease progression in chronic hepatitis C infection (CHC). We investigated At-PI diagnostic efficacy in predicting development of collateral veins. METHODS: In total, 171 CHC patients underwent CEUS and upper gastrointestinal (UGI) endoscopy before liver biopsy. Conventional US was performed before CEUS to identify paraumbilical veins (PV) or splenorenal shunts (SRS). After intravenous perflubutane, contrast dynamics of liver segments 5-6 and the right kidney were saved as raw data. At-PI image ratio of red (ROR) pixels to the entire liver was analyzed. Receiver operating characteristic (ROC) curves were generated to investigate the utility of At-PI for collateral vein identification. RESULTS: Conventional US revealed PV in two patients and SRS in five patients; UGI endoscopy detected esophageal varices (EV) in eight patients. Diagnostic capability of At-PI for detecting PV, SRS, and EV was satisfactory, and high for PV and SRS [PV; area under the ROC curve (AUROC) 0.929, cutoff value 77.9%, SRS; AUROC 0.970, cutoff value 82.0%, EV; AUROC 0.883, cutoff value 66.9%]. CONCLUSIONS: Evaluation of hepatic arterialization by At-PI was useful for predicting collateral vein development in CHC patients.

Comparison of neurodevelopmental outcomes between monochorionic and dichorionic twins with birth weight ≤ 1500 g in Japan: a register-based cohort study.

OBJECTIVE: To examine the relationship between chorionicity and neurodevelopmental outcomes in very low birth weight twins at 3 years of age. STUDY DESIGN: A retrospective cohort study of 3538 twins who were admitted to 91 tertiary perinatal centers in the Neonatal Research Network of Japan between 2003 and 2012. RESULTS: In a comparison of the followed-up 796 monochorionic twins and 786 dichorionic twins, the overall rate of neurodevelopmental impairment was higher in monochorionic twins; specifically, the rate of disability in the language-social area of the Japanese standardized developmental test was higher in monochorionic twins than in dichorionic twins (adjusted odds ratio, 1.55; 95% confidence interval, 1.07-2.25; P = 0.02). CONCLUSIONS: Chorionicity was associated with neurodevelopmental outcome (especially for language and social development) in a large cohort of very low birth weight twins who had a high rate of perinatal morbidity and neurodevelopmental impairment.

Effect of Hepatic Inflammation in Chronic Hepatitis C Infection on Fibrosis Assessment by Arrival Time Parametric Imaging.

Arrival time parametric imaging (At-PI) in contrast-enhanced ultrasonography is useful for assessing liver fibrosis in chronic hepatitis C (CHC) infection. The study aimed to elucidate the effect of hepatic inflammation on At-PI efficiency. Subjects were 159 CHC patients who underwent contrast-enhanced ultrasonography immediately before liver biopsy. Ultrasound contrast agent was injected, and contrast dynamics of the S5 to S6 region of the liver and right kidney were recorded for 40 seconds. The At-PI of liver parenchyma blood flow was generated using saved video clips. Hepatic blood flow during the first 5 seconds after starting contrast injection was displayed in red and that after another 5 seconds was displayed in yellow. The ratio of red (ROR) in At-PI images of the entire liver was measured with ImageJ. Ratio of red values of livers with different activity grades (0-3) were compared for each fibrosis (F) stage as determined by biopsy. Correlations of ROR with alanine aminotransferase (ALT) levels were analyzed using a linear regression line from the distribution map. Comparison of ROR for different activity grades in each F stage revealed no significant differences. Correlation coefficient R (P value) for ALT and ROR was R = -0.0094 (P = 0.43) at F0 to F1, R = -0.186 (P = 0.21) at F2, R = -0.233 (P = 0.27) at F3, and R = 0.041 (P = 0.89) at F4, with no significant correlation between ALT and ROR in any F stage. Hepatic inflammation in CHC infection does not affect At-PI diagnostic accuracy.

Perinatal Factors Affecting Serum Hepcidin Levels in Low-Birth-Weight Infants.

BACKGROUND: Hepcidin, an iron-regulatory hormone, plays a key role in preventing iron overload. Few studies have investigated the regulation of hepcidin in low-birth-weight (LBW) infants who are vulnerable to iron imbalance. OBJECTIVES: To identify perinatal factors associated with serum hepcidin levels in LBW infants. METHODS: Ninety-two LBW infants with a median gestational age (GA) of 32.6 weeks and birth weight of 1,587 g were prospectively enrolled. Serum hepcidin-25 (Hep25) levels were measured from umbilical cord blood using liquid chromatography-tandem mass spectrometry. The relationship between Hep25 levels and prematurity or other possible hepcidin-regulatory factors was evaluated. RESULTS: The median Hep25 level was 7.3 ng/mL (interquartile range: 2.85-16.38). log(Hep25) correlated with birth weight (r = 0.229, p = 0.028), log(interleukin-6 [IL-6]) (r = 0.408, p < 0.001), log(erythropoietin) (r = -0.302, p = 0.004), transferrin saturation (r = 0.29, p = 0.005), soluble transferrin receptor (r = -0.500, p < 0.001), and log(ferritin) (r = 0.696, p < 0.001). Serum iron and hemoglobin levels did not correlate with log(Hep25). Hep25 levels were higher among infants with chorioamnionitis and infants born vaginally and lower among infants born to mothers with pregnancy-induced hypertension than among infants without the respective characteristics. Stepwise multiple linear regression analysis confirmed the significant association of log(Hep25) with GA, log(IL-6), log(erythropoietin), and soluble transferrin receptor. CONCLUSIONS: Among LBW infants, GA, IL-6, erythropoietin, and soluble transferrin receptor were associated with Hep25 levels. Therefore, prematurity, inflammation, hypoxia, and erythropoietic activity may be important perinatal factors that affect hepcidin levels.

Serum α-fetoprotein concentration in extremely low-birthweight infants.

BACKGROUND: Extremely low-birthweight infants (ELBWI) are at greater risk of developing hepatoblastoma than are normal-weight infants. Serum α-fetoprotein (AFP) plays an important role as a tumor marker in the diagnosis of hepatoblastoma, therefore the aim of this study was to determine the changes in serum AFP concentration after birth in ELBWI. METHODS: Data were obtained for infants born between January 2005 and March 2008 with birthweight <1000 g who were followed up at Gunma Children's Medical Center with clinical examinations, including monitoring of the development of hepatoblastoma. The relationship between serum AFP concentration and age was analyzed up to 730 days after birth. RESULTS: Overall, 95 serum AFP measurements were obtained from 23 infants 30-730 days of age, with gestational age 24-32 weeks, and birthweight 498-982 g. Log10 (AFP [ng/mL]) was significantly correlated with log10 (age [days]) (r = -0.961, P = 0.000, n = 95), with the following regression formula: log10 (AFP [ng/mL]) = 11.063 - 3.752 log10 (age [days]) (adjusted R2  = 0.923, n = 95). The standard error of the estimate, mean log10 (age [days]), and the sum of squares for log10 (age [days]) were 0.363, 2.503, and 10.579, respectively. CONCLUSIONS: A correlation was found between serum AFP concentration and age in ELBWI, and the 95%CI of serum AFP concentration was determined for ELBWI up to 2 years after birth.

IP-10 Is Elevated in Virus-Induced Acute Exacerbations in Childhood Asthma.

OBJECTIVE: Viral infections and sensitization to aeroallergens are major factors in the exacerbation of asthma and its development during early childhood. However, the cytokine profiles and eosinophil activation status linked to the association between viral infections and sensitization to aeroallergens are incompletely understood. Here we investigated respiratory viruses, serum eosinophil cationic protein (ECP), and various cytokines/chemokines in acute exacerbation of childhood asthma. METHODS: We analyzed peripheral eosinophil counts, serum ECP, and 27 cytokines/chemokines in 76 virus-induced acute asthma cases with or without aeroallergen sensitization. Asthma due to sensitization was defined by a positive reaction to at least one aeroallergen in serum specific IgE antibody tests. Virus detection was performed using antigen detection kits and/or RT-PCR, followed by direct DNA sequencing analysis. Serum cytokines/chemokines were measured using a multi-cytokine detection system. RESULTS: Peripheral eosinophil counts and serum ECP and IL-5 levels were significantly elevated in sensitized cases compared with nonsensitized cases. Conversely, IP-10 values were significantly higher in nonsensitized cases. An inverse correlation between IP-10 and IL-5 production was identified in virus-induced acute exacerbations of asthma but not in controls. CONCLUSIONS: Cytokine profiles and eosinophil activation status might be different between sensitized and nonsensitized cases of virus-induced acute exacerbations of asthma.

Siladifluoromethylation and Difluoromethylation onto C(sp(3)), C(sp(2)), and C(sp) Centers Using Ruppert-Prakash Reagent and Fluoroform.

Siladifluoromethylations and difluoromethylations on sp(3), sp(2), and sp carbons of lithiated carbamates, arenes, and terminal alkynes, respectively, have been attained by employing the Ruppert-Prakash reagent (CF3TMS) and fluoroform (CF3H) as the CF2 sources. The advantage of this reaction is that the (sila)difluoromethylated compounds can be obtained by simple treatment of easily accessible substrates, lithium bases, and CF3TMS or CF3H. Furthermore, the products bearing the TMS group can be transformed into the valuable compounds with the CF2 fragment via the carbon-carbon bond forming reactions.

Virus detection and cytokine profile in relation to age among acute exacerbations of childhood asthma.

BACKGROUND: Little information is available regarding eosinophil activation and cytokine profiles in relation to age in virus-induced bronchial asthma. We therefore explored the association between age, respiratory viruses, serum eosinophil cationic protein (ECP), and cytokines/chemokines in acute exacerbations of childhood asthma. METHODS: We investigated viruses in nasal secretions from 88 patients with acute exacerbation of childhood asthma by using antigen detection kits and/or RT-PCR, followed by direct DNA sequencing analysis. We also measured peripheral eosinophil counts, and the serum levels of ECP and 27 types of cytokines/chemokines in 71 virus-induced acute asthma cases and 13 controls. RESULTS: Viruses were detected in 71(80.7%) of the 88 samples. The three major viruses detected were rhinoviruses, RS viruses, and enteroviruses; enteroviruses were found to be dominant in patients aged ≥3 years. There was no change in the levels of rhinoviruses and RS viruses between the two age groups, defined as children aged <3 years and children aged ≥3 years. Serum concentrations of ECP, IL-5, and IP-10 were significantly elevated in virus-induced acute asthma cases compared with controls. Serum ECP values were significantly higher in patients with virus-induced asthma at age ≥3 years compared with those aged <3 years. Among the 27 cytokines/chemokines, serum IP-10 was significantly higher in virus-induced asthma in patients <3 years than in those ≥3 years. Serum ECP and IL-5 production correlated significantly with age, whereas serum IP-10 showed an inverse correlation with age. CONCLUSIONS: Age-related differences in cytokine profiles and eosinophil activation may be related to virus-induced acute exacerbations of childhood asthma.

α-Difluoromethylation on sp(3) Carbon of Nitriles Using Fluoroform and Ruppert-Prakash Reagent.

Difluoromethylation on sp(3) carbon of various nitrile compounds with lithium base and fluoroform (CF3H), which is an ideal difluoromethylating reagent, is shown to provide the α-difluoromethylated nitrile products with an all-carbon quaternary center in moderate to high yields. The Ruppert-Prakash reagent (CF3TMS) is also applicable to the reaction, affording the α-siladifluoromethylated nitrile products, which can be utilized for sequential carbon-carbon bond-forming reactions. These reactions using 1.1 equiv of lithium base, 1.5-2.0 equiv of CF3H or CF3TMS, and easily accessible nitrile derivatives are completed in only a few minutes, resulting in the formation of valuable difluoromethylated compounds.

Ambipolar light-emitting organic single-crystal transistors with a grating resonator.

Electrically driven organic lasers are among the best lasing devices due to their rich variety of emission colors as well as other advantages, including printability, flexibility, and stretchability. However, electrically driven lasing in organic materials has not yet been demonstrated because of serious luminescent efficiency roll-off under high current density. Recently, we found that the organic ambipolar single-crystal transistor is an excellent candidate for lasing devices because it exhibits less efficient roll-off, high current density, and high luminescent efficiency. Although a single-mode resonator combined with light-emitting transistors (LETs) is necessary for electrically driven lasing devices, the fragility of organic crystals has strictly limited the fabrication of resonators, and LETs with optical cavities have never been fabricated until now. To achieve this goal, we improved the soft ultraviolet-nanoimprint lithography method and demonstrated electroluminescence from a single-crystal LET with a grating resonator, which is a crucial milestone for future organic lasers.

Age at onset of asthma and allergen sensitization early in life.

BACKGROUND: Epidemiological evidence indicates that the age at onset of asthma and allergen sensitization in early life is decreasing in people from Western countries. To explore latent trends, we conducted a retrospective examination of the age at onset of asthma and specific IgE antibodies against inhalant allergens in Japanese asthmatic children. METHODS: We conducted a case series study of 103 consecutive children with atopic type of asthma (aged 2 years to 16 years, mean age 9.4 ± 3.4 years). Diagnoses of asthma and allergic rhinitis were defined according to Japanese guidelines. The onset of asthma and allergic rhinitis was also defined as any report of asthma and allergic rhinitis confirmed by a physician. Allergen sensitization was evaluated as specific serum IgE levels for 9 common inhalant allergens in peripheral blood. Atopic type of asthma was defined as a being positive for at least one aeroallergen. RESULTS: Mean age at asthma onset was 2.3 ± 1.9 years, which is slightly lower than that of previous reports, including those published in Japan. A high prevalence rate of up to 80% was found for perennial antigens including Dermatophagoides spp. and house dust, as reported previously. Notably, some of the children aged at 1 year tested positive for these allergens. CONCLUSIONS: The age at onset of asthma seems to be decreasing in comparison with previous reports. Furthermore, the age at onset of allergen sensitization against inhalant allergens appears to follow this trend.

Problems with using total serum bilirubin as a criterion for phototherapy in extremely low-birthweight infants.

BACKGROUND: Despite the early use of phototherapy and exchange transfusion in premature infants based on total serum bilirubin (TSB), the reemergence of kernicterus has been reported. The aim of this study was to assess the validity of using TSB as the criterion for phototherapy in extremely low-birthweight infants (ELBWI). METHODS: We reviewed the medical charts of 43 ELBWI admitted to hospital between January 2009 and December 2010, and analyzed the relationship between TSB and unbound bilirubin (UB). RESULTS: No infant underwent exchange transfusion or developed acute bilirubin encephalopathy. There was a significant correlation between TSB and UB measured immediately before phototherapy during the first 7 days of life (r = 0.657, P < 0.001), but none thereafter (r = 0.120, P = 0.213). Thirty-seven percent of infants who underwent phototherapy during the first 7 days of life had suprathreshold USB but subthreshold TSB, whereas this rose to 97% thereafter. CONCLUSIONS: No correlation was observed between TSB and UB in ELBWI after the first 7 days of life, and almost all phototherapy sessions were initiated based on the UB criterion, even though TSB was below the accepted threshold. UB may be high if jaundice is evaluated solely on the basis of TSB.

Liver disease is frequently observed in Down syndrome patients with transient abnormal myelopoiesis.

Transient abnormal myelopoiesis (TAM) in neonates with Down syndrome (DS) is characterized by the transient appearance of blast cells, which resolves spontaneously. Approximately 20 % of patients with TAM die at an early age due to organ failure, including liver disease. We studied 25 DS-TAM patients retrospectively to clarify the correlation between clinical and laboratory characteristics and liver diseases. Early death (<6 months of age) occurred in four of the 25 patients (16.0 %), and two of those four patients died due to liver failure. Although physiologic jaundice improved gradually after a week, all DS patients had elevated D-Bil levels during the clinical course of TAM, except one who suffered early death. The median peak day of the WBC count, total bilirubin (T-Bil) and D-Bil levels was: day 1 (range day 0-57), day 8 (range day 1-55), and day 17 (range 1-53), respectively. Our results reveal that all patients with DS-TAM may develop liver disease irrespective of the absence or presence of symptoms and risk factors for early death. In patients of DS-TAM, careful observation of the level of D-Bil is needed by at least 1 month of age for the detection of liver disease risk.

Elevated macrophage inflammatory protein 1α and interleukin-17 production in an experimental asthma model infected with respiratory syncytial virus.

BACKGROUND: Respiratory syncytial virus (RSV) infection is associated with both the development and exacerbation of bronchial asthma. We examined eosinophil infiltration and the cytokine profiles of both airway and peripheral blood in antigen-sensitized mice infected with RSV to investigate the pathogenesis of exacerbations of asthma due to RSV infection. METHODS: Ovalbumin (OVA)-sensitized mice were challenged by OVA inhalation 3 times and then infected with RSV [10(5) TCID50 (50% of tissue culture infectious dose)/25 g body weight] or mock infection immediately after the last challenge. Animals from each group, namely, the control (PBS instead of OVA inhalation plus mock infection), RSV (PBS plus RSV), OVA (OVA plus mock) and OVA/RSV (OVA plus RSV) were analyzed. Analysis included evaluation of airway responsiveness to methacholine, pathological findings in the airway by hematoxylin and eosin (HE) and Luna staining, bronchoalveolar fluid (BALF) and peripheral leukocytes counts, and concentrations of multiple cytokines/chemokines in both BALF and serum. RESULTS: Airway responsiveness was significantly enhanced in the OVA and OVA/RSV groups compared with the control group. Levels of tissue and BALF eosinophils were higher in the OVA and OVA/RSV groups than in the RSV or control group. Significantly higher levels of macrophage inflammatory protein (MIP)-1α in BALF were observed in the OVA/RSV group compared with the 3 other groups. Production of serum IL-17 was also significantly elevated in the OVA/RSV group compared with the control or OVA group. CONCLUSIONS: These findings suggest that MIP-1α and IL-17 may play important roles in acute exacerbation of asthma induced by RSV in an animal model.

Feeding interval and postprandial intestinal blood flow in premature infants.

BACKGROUND: The feeding interval is an important factor in enteral feeding of premature infants. We investigated postprandial intestinal blood flow in stable very-low-birthweight infants fed at 2-h and 3-h intervals. METHODS: We used pulsed wave Doppler ultrasound to measure blood flow velocity of the superior mesenteric artery (SMA) before feeding and at 15, 30, 45, and 60 min after feeding. Measurements were made on the day of starting enteral nutrition (1 or 2 days of age), and at 3 and 5 days of age. A total of 21 studies were performed in seven infants fed every 2 h, and 54 studies were performed in 18 infants fed every 3 h. RESULTS: In infants fed every 2 h, SMA blood flow velocity increased from before feeding to 30 min after feeding and then decreased at 60 min after feeding. In infants fed every 3 h, SMA blood flow velocity increased after feeding, reaching a peak at 30 min. The correlation coefficients between the volume of milk per feed and the postprandial increase in time-averaged mean blood flow velocity were 0.398 (P = 0.074, n = 21) and 0.597 (P = 0.000, n = 54) in infants fed at 2-h and 3-h intervals, respectively. CONCLUSIONS: SMA blood flow velocity significantly increased after feeding in infants fed at 2-h and 3-h intervals. The volume of milk per feed might affect the postprandial increase in SMA blood flow velocity.