Influence of household pet ownership and filaggrin loss-of-function mutations on eczema prevalence in children: A birth cohort study

BACKGROUND

The association between pet exposure in infancy, early childhood eczema, and FLG mutations remains unclear.

METHODS

This was a birth cohort study performed in Tokyo, Japan. The primary outcome was current eczema based on questionnaire responses collected repeatedly from birth to 5 years of age. Generalized estimating equations and generalized linear modeling were used to evaluate the association.

RESULTS

Data from 1448 participants were used for analyses. Household dog ownership during gestation, early infancy, and 18 months of age significantly reduced the risk of current eczema. Household cat ownership also reduced the risk of current eczema, albeit without statistical significance. The combined evaluation of children from households with pets, be it cats, dogs or both, the risk of current eczema at 1-5 years of age was lower in those with household pet exposure ownership during gestation (RR = 0.59, 95 % CI 0.45-0.77) and at 6 months (RR = 0.49, 95 % CI 0.36-0.68). , Reduced risks of eczema were also observed at 2-5 (RR = 0.52, 95 % CI 0.37-0.73) and 3-5 years of age (RR = 0.50 95 % CI 0.35-0.74) when the respective household pet ownership were evaluated at 18 months and 3 years of age. These protective associations of reduced risk of eczema were only observed in children without FLG mutations.

CONCLUSIONS

Household dog and pet (dog, cat, or both) ownership was protective against early childhood eczema in a birth cohort dataset. This protective association was observed only in children without FLG mutations, which should be confirmed in studies with larger cohorts.

Lattice dynamics and carrier recombination in GaAs/GaAsBi nanowires

GaAsBi nanowires represent a novel and promising material platform for future nano-photonics. However, the growth of high-quality GaAsBi nanowires and GaAsBi alloy is still a challenge due to a large miscibility gap between GaAs and GaBi. In this work we investigate effects of Bi incorporation on lattice dynamics and carrier recombination processes in GaAs/GaAsBi core/shell nanowires grown by molecular-beam epitaxy. By employing photoluminescence (PL), PL excitation, and Raman scattering spectroscopies complemented by scanning electron microscopy, we show that increasing Bi-beam equivalent pressure (BEP) during the growth does not necessarily result in a higher alloy composition but largely affects the carrier localization in GaAsBi. Specifically, it is found that under high BEP, bismuth tends either to be expelled from a nanowire shell towards its surface or to form larger clusters within the GaAsBi shell. Due to these two processes the bandgap of the Bi-containing shell remains practically independent of the Bi BEP, while the emission spectra of the NWs experience a significant red shift under increased Bi supply as a result of the localization effect.

Enhanced early skin treatment for atopic dermatitis in infants reduces food allergy

BACKGROUND

Early-onset atopic dermatitis is a strong risk factor for food allergy, suggesting that early effective treatment may prevent transcutaneous sensitization.

OBJECTIVES

This study tested whether enhanced treatment of atopic dermatitis to clinically affected and unaffected skin is more effective in preventing hen's egg allergy than reactive treatment to clinically affected skin only.

METHODS

This was a multicenter, parallel-group, open-label, assessor-blind, randomized controlled trial (PACI [Prevention of Allergy via Cutaneous Intervention] study). This study enrolled infants 7-13 weeks old with atopic dermatitis and randomly assigned infants in a 1:1 ratio to enhanced early skin treatment or conventional reactive treatment using topical corticosteroids (TCSs). The primary outcome was the proportion of immediate hen's egg allergy confirmed by oral food challenge at 28 weeks of age.

RESULTS

This study enrolled 650 infants and analyzed 640 infants (enhanced [n = 318] or conventional [n = 322] treatment). Enhanced treatment significantly reduced hen's egg allergy compared with the conventional treatment (31.4% vs 41.9%, P = .0028; risk difference: -10.5%, upper bound of a 1-sided CI: -3.0%), while it lowered body weight (mean difference: -422 g, 95% CI: -553 to -292 g) and height (mean difference: -0.8 cm, 95% CI: -1.22 to -0.33 cm) at 28 weeks of age.

CONCLUSIONS

This study highlighted the potential of well-controlled atopic dermatitis management as a component of a hen's egg allergy prevention strategy. The enhanced treatment protocol of this trial should be modified before it can be considered as an approach to prevent hen's egg allergy in daily practice to avoid the adverse effects of TCSs. After remission induction by TCSs, maintenance therapy with lower potency TCSs or other topical therapies might be considered as alternative proactive treatments to overcome the safety concerns of TCSs.

[A CASE OF INDUCIBLE LARYNGEAL OBSTRUCTION UNSUCCESSFULLY TREATED AS SEVERE ASTHMA WAS WELL CONTROLLED AFTER APPROPRIATE DIAGNOSIS AND INSTRUCTION OF THERAPEUTIC BREATHING MANEUVERS]

BACKGROUND

Inducible laryngeal obstruction (ILO) refers to respiratory disorders caused by airflow limitation in the larynx, including vocal cord dysfunction, and may sometimes be misdiagnosed as bronchial asthma (BA). Here, we report the case of an 11-year-old boy diagnosed with BA in infancy. He was referred to our Allergy Center and was taking a high dose of inhaled corticosteroids (ICS) due to frequent coughing from the age of 10 years and persistent coughing following COVID-19 infection at the age of 11. However, the patient continued to experience frequent coughing attacks and repeated visits to the emergency department after inhalation of β₂-stimulants failed to improve his cough. We admitted him to the allergy center for examinations to assess the BA severity. In the airway hypersensitiveness test, saline inhalation performed prior to methacholine inhalation caused expiratory stridor and respiratory distress in the larynx, which worsened with β₂-stimulant inhalation. Based on these results, we ruled out BA and diagnosed ILO. We instructed him on breathing maneuvers, and he was able to respond appropriately when symptoms appeared. We then started reducing his ICS dose.

Pollen Food Allergy Syndrome in Allergic March

The association between pollen food allergy syndrome (PFAS) and allergic march remains unclear. In this prospective cohort study of the general population in Tokyo (T-Child Study), we found that sensitization to Cry j 1 and Fel d 1 at ages 5 and 9 years was associated with an increased risk of PFAS at 13 years old (at 5 years, Cry j 1: adjusted odds ratio aOR, 2.74; 95% confidence interval CI, 1.53–4.91; Fel d 1: aOR, 2.61; 95% CI, 1.31–5.19; at 9 years, Cry j 1: adjusted odds ratio aOR, 4.28; 95% confidence interval CI, 1.98–9.25; Fel d 1: aOR, 2.40; 95% CI, 1.33–4.32). In particular, sensitization to Bet v 1 at ages 5 and 9 years was associated with a strong risk of PFAS at the age of 13 years (at 5 years: aOR, 10.6; 95% CI, 2.64–42.5; at 9 years: aOR, 9.1; 95% CI, 4.71–17.6). PFAS risk by age 13 years was increased by any allergic symptom at 5 or 9 years, a combination of wheezing, eczema, and rhinitis, and Bet v 1 sensitization. Our findings suggest that PFAS may be associated with allergic march.

Pollen-food allergy syndrome and component sensitization in adolescents: A Japanese population-based study

Allergic rhino-conjunctivitis with pollen allergy has been prevalent worldwide and Pollen-food allergy syndrome (PFAS) refers to individuals with pollen allergy who develop oral allergy syndrome (OAS) on consuming fruits and vegetables. The prevalence of PFAS varies by region and that in Japanese adolescents remains to be elucidated. In this cross-sectional study, we examined the epidemiological characteristics of PFAS in a general population of Japanese adolescents according to pollen allergy, OAS, and IgE component sensitization. Participants comprised adolescents, at age 13 years, from a prospective birth cohort study in Japan. We administered questionnaires to collect information from parents regarding pollen allergy, PFAS and OAS at each child’s age 13 years. ImmunoCAP ISAC was used to assess IgE component sensitization. Among 506 participants with a complete questionnaire and ISAC measurement results, 56.5% had a history of hay fever, 16.0% had a history of OAS, 51.0% had pollen allergy, and 11.7% had a history of PFAS; additionally, 72.7% were sensitized to one or more tree, grass, and/or weed allergens. The most common sensitization (95.7%) among adolescents with pollen allergy was to Japanese cedar (Cry j 1). The most common causal foods were kiwi and pineapple (both 39.0%). Knowledge levels about PFAS were poor among affected adolescents. We found a high prevalence of PFAS among adolescents in Japan. Although it affects approximately 1/10 adolescents in the general population, public awareness regarding PFAS is poor. Interventional strategies are needed to increase knowledge and to prevent PFAS in the general population.

Polytypism in GaAs/GaNAs core-shell nanowires

We report the crystal structures of GaAs and GaAs/GaNAs/GaAs core-multishell nanowires (NWs). From statistical investigations by x-ray diffraction (XRD) and electron backscattered diffraction (EBSD) pattern analysis, we statistically and microscopically resolve the zinc-blende (ZB) and wurtzite (WZ) polytypism within the NWs. The XRD analysis shows a smaller fraction of WZ segments in the NWs with a larger concentration of nitrogen. With increasing nitrogen content in the GaNAs shell, the ZB peak position shifts toward higher angles and the WZ peak intensity decreases. The EBSD measurements also confirm the coexistence of ZB and WZ polytypes in all of the NWs. Their polytype switches along the length. Twin defects are observed in the ZB segments in all of the NWs. The unique grain map and grain size distribution show a decrease of the WZ segments in the GaAs/GaNAs/GaAs NW, in agreement with the XRD results. Microscopically, the local area where the polytype switches from WZ in the inner-core side to ZB toward the outer-shell surface is observed. Overall, we propose that the WZ polytype in the GaAs NWs decreases because of the strain induced by the growth of the GaNAs shell with a smaller lattice constant.

Impact of swimming school attendance in 3-year-old children with wheeze and rhinitis at age 5 years: A prospective birth cohort study in Tokyo

Background

In Japan, swimming school attendance is promoted as a form of therapy or as a prophylactic measure against asthma in young children. However, the putative beneficial effects have not been sufficiently verified.

Objective

The aim of the present study was to clarify whether or not swimming school attendance at age 3 years affects the onset and/or improvement of wheeze and rhinitis at age 5 years.

Methods

This study was a single-center, prospective, general, longitudinal cohort study (T-CHILD Study). Between November 2003 and December 2005, 1776 pregnant women were enrolled, and their offspring were followed up until age 5 years. Swimming school attendance at age 3 years and the presence of wheeze and/or rhinitis in the previous one year were examined using the International Study of Asthma and Allergies in Childhood (ISAAC) questionnaire. The relationship between swimming school attendance and wheeze and/or rhinitis was analyzed using multivariable logistic regression analysis.

Results

Data on the 1097 children were analyzed. At age 3 years, 126 (11.5%) children attended a swimming school, and at age 5 years, the prevalence of wheeze was 180 (16.4%) while that of rhinitis was 387 (35.3%). Swimming school attendance at age 3 showed no significant relationship with the development of either wheeze (aOR 0.83, 95% CI (0.43–1.60) or rhinitis (aOR 0.80, 95% CI (0.43–1.60) at age 5.

Conclusions

Swimming school attendance at age 3 years showed neither a preventive nor therapeutic effect on wheeze or rhinitis at age 5 years. There is thus no scientific evidence yet that swimming school attendance has a positive impact on the development of childhood wheeze or rhinitis.

Effects of growth temperature and thermal annealing on optical quality of GaNAs nanowires emitting in the near-infrared spectral range

We report on optimization of growth conditions of GaAs/GaNAs/GaAs core/shell/shell nanowire (NW) structures emitting at ∼1 μm, aiming to increase their light emitting efficiency. A slight change in growth temperature is found to critically affect optical quality of the active GaNAs shell and is shown to result from suppressed formation of non-radiative recombination (NRR) centers under the optimum growth temperature. By employing the optically detected magnetic resonance spectroscopy, we identify gallium vacancies and gallium interstitials as being among the dominant NRR defects. The radiative efficiency of the NWs can be further improved by post-growth annealing at 680 °C, which removes the gallium interstitials.

Superconductivity under pressure in the Dirac semimetal PdTe2

The Dirac semimetal PdTe₂ was recently reported to be a type-I superconductor (T _c   =  1.64 K, [Formula: see text] mT) with unusual superconductivity of the surface sheath. We here report a high-pressure study, [Formula: see text] GPa, of the superconducting phase diagram extracted from ac-susceptibility and transport measurements on single crystalline samples. T _c (p ) shows a pronounced non-monotonous variation with a maximum T _c   =  1.91 K around 0.91 GPa, followed by a gradual decrease to 1.27 K at 2.5 GPa. Surface superconductivity is robust under pressure as demonstrated by the large superconducting screening signal that persists for applied dc-fields [Formula: see text]. Surprisingly, for [Formula: see text] GPa the superconducting transition temperature at the surface [Formula: see text] is larger than T _c of the bulk. Therefore surface superconductivity may possibly have a non-trivial topological nature. We compare the measured pressure variation of T _c with recent results from band structure calculations and discuss the importance of a Van Hove singularity.

Avoidance of Hen's Egg Based on IgE Levels Should Be Avoided for Children With Hen's Egg Allergy

Background: Although hen's egg (HE) allergy was thought to be usually resolved by late childhood, majority of HE allergy patients with a high level of egg white (HEW)-specific IgE could not acquire tolerance for HE by age 8 years. Objective: The aim is to investigate whether the avoidance of HE until 6 years of age increased the risk of heated HE allergy at age 6 years. Methods: This was a retrospective case-control study. The HE tolerance children (n = 17) and children with low-dose HE reactor [a positive reaction to ≤ 4 g of heated HEW in oral food challenges (OFCs)] children (n = 26) were included based on the results of OFC at 6 years old. Multivariate logistic regression analysis was applied to examine the associations between HE avoidance until age 6 years and HE allergy status confirmed by OFC, adjusting the level of ovomucoid-specific IgE (OM-sIgE) during early infancy. Results: A lower proportion of strict avoidance of HE was observed in the HE tolerance group than in the low-dose HE reactor group (6 vs. 46%, p = 0.006). OM-sIgE levels in children younger than 2 years old were significantly higher in the low-dose HE reactor group than those in the HE tolerance group (median [interquartile], 26.7 UA/mL [11.9-53.4] vs. 7.9 UA/mL [0.35-23.4]; p =0.024). The avoidance of HE until 6 years of age increased the risk of heated HE allergy even after adjusting OM-sIgE levels. Conclusions: The long-term avoidance of HE from infancy increased the risk of heated HE allergy confirmed by OFC at age 6 years.

[A CASE OF EOSINOPHILIC GASTROENTERITIS FOUND BY PICA DURING ORAL IMMUNOTHERAPY]

Eosinophilic esophagitis has been reported as a complication of oral immunotherapy (OIT), but there are only a few reports of eosinophilic gastroenteritis (EGE) occurring after OIT. EGE causes eosinophil infiltration into the gastrointestinal (GI) tract and is characterized by various digestive symptoms. We report the case of a 6-year-old boy with EGE. He was diagnosed as having immediate-type food allergies (egg, milk and wheat) by oral food challenges at 1 year of age. OIT for each food was carried out, and the amounts of the offending foods were able to be gradually increased without causing any immediate-type allergy symptoms. However, the total IgE and specific IgE values were remarkably increased at the age of 4 years and 4 months. He first developed oral mucosa symptoms and vomiting at 4 years and 10 months of age, and they gradually worsened. Stopping eggs and milk alleviated the symptoms. Nevertheless, he still occasionally vomited. He started Pica eating disorder (sand and sponge) due to anemia from 5 years and 10 months of age and developed eosinophilia without diarrhea or bloody stool. Upper and lower GI tract endoscopic examinations found no bleeding. The GI mucosa showed eosinophil infiltration of more than 40/high-power field in the stomach and duodenum, so he was diagnosed with EGE. No eosinophils were found in the esophageal mucosa. His GI symptoms and anemia improved on a multiple-food-elimination diet. Patients undergoing OIT should be closely followed up for a long time, and those with GI symptoms should be evaluated by GI endoscopy.

Molecular beam epitaxial growth of dilute nitride GaNAs and GaInNAs nanowires

We report the growth of dilute nitride GaNAs and GaInNAs core-multishell nanowires (NWs) using molecular beam epitaxy assisted by a plasma source. Using the self-catalyst vapor-liquid-solid growth mode, these NWs were grown on Si(111) and silicon on insulator substrates. The GaNAs and GaInNAs shells contain nitrogen up to 3%. Axial cross-sectional scanning transmission electron microscopy measurements and energy-dispersive x-ray spectrometry confirm the formation of the core-multishell NW structure. We obtained high-quality GaNAs NWs with nitrogen compositions up to 2%. On the other hand, GaNAs containing 3% nitrogen, and GaInNAs NWs, show distorted structures; moreover, the optical emissions seem to be related to defects. Further optimisations of the growth conditions will improve these properties, promising future applications in nanoscale optoelectronics.

Strongly polarized quantum-dot-like light emitters embedded in GaAs/GaNAs core/shell nanowires

Recent developments in fabrication techniques and extensive investigations of the physical properties of III-V semiconductor nanowires (NWs), such as GaAs NWs, have demonstrated their potential for a multitude of advanced electronic and photonics applications. Alloying of GaAs with nitrogen can further enhance the performance and extend the device functionality via intentional defects and heterostructure engineering in GaNAs and GaAs/GaNAs coaxial NWs. In this work, it is shown that incorporation of nitrogen in GaAs NWs leads to formation of three-dimensional confining potentials caused by short-range fluctuations in the nitrogen composition, which are superimposed on long-range alloy disorder. The resulting localized states exhibit a quantum-dot like electronic structure, forming optically active states in the GaNAs shell. By directly correlating the structural and optical properties of individual NWs, it is also shown that formation of the localized states is efficient in pure zinc-blende wires and is further facilitated by structural polymorphism. The light emission from these localized states is found to be spectrally narrow (∼50-130 μeV) and is highly polarized (up to 100%) with the preferable polarization direction orthogonal to the NW axis, suggesting a preferential orientation of the localization potential. These properties of self-assembled nano-emitters embedded in the GaNAs-based nanowire structures may be attractive for potential optoelectronic applications.

Double-blind, placebo-controlled pilot trial of anthocyanin-rich purple sweet potato beverage on serum hepatic biomarker levels in healthy Caucasians with borderline hepatitis

The objective is to evaluate the efficacy of anthocyanin-rich purple-fleshed sweet potato (PSP) beverage on the serum levels of gamma-glutamyl transferase (GGT), aspartate aminotransferase (AST) and alanine aminotransferase (ALT) in healthy Caucasians with borderline hepatitis. Forty healthy Caucasians (41-69 years) consumed three bottles of the PSP beverage (177 mg anthocyanins per 125-ml bottle) or placebo (1.3 mg) per day for 8 weeks. Thirty-nine subjects completed the study and two subjects were excluded from statistical analysis. GGT levels in the PSP group on days 15 and 43 were lower (P=0.077 and 0.038, respectively), AST levels in the PSP group on days 29 and 43 were lower (P=0.010 and 0.045, respectively) and ALT level in the PSP group on day 43 was lower (P=0.037) than in the placebo group. The PSP beverage did not induce clinically relevant changes in other blood and clinical chemistry parameters.

Note: Application of CR-39 plastic nuclear track detectors for quality assurance of mixed oxide fuel pellets

A CR-39 plastic nuclear track detector was used for quality assurance of mixed oxide fuel pellets for next-generation nuclear power plants. Plutonium (Pu) spot sizes and concentrations in the pellets are significant parameters for safe use in the plants. We developed an automatic Pu detection system based on dense α-radiation tracks in the CR-39 detectors. This system would greatly improve image processing time and measurement accuracy, and will be a powerful tool for rapid pellet quality assurance screening.

Health benefits of fermented milk containing Bifidobacterium bifidum YIT 10347 on gastric symptoms in adults

We conducted a preliminary open trial (trial 1) and a double-blind, placebo-controlled, crossover trial (trial 2) to examine how fermented milk containing the probiotic Bifidobacterium bifidum YIT 10347 affects gastric and lower abdominal symptoms in adults taking no medication. In trial 1, subjects with or without gastric and lower abdominal symptoms ingested fermented milk containing B. bifidum YIT 10347 daily for 2 wk. In trial 2, subjects with gastric symptoms ingested fermented milk containing B. bifidum YIT 10347 (active preparation) or placebo daily for 2 wk, followed by crossover for 3 wk after a washout period. Before (baseline) and 1 and 2 wk after ingestion, subjects completed a questionnaire. In trial 1 (305 subjects), the prevalence of gastric and lower abdominal symptoms was 46 and 58%, respectively, at baseline. Ingestion of B. bifidum YIT 10347 significantly decreased the prevalence of gastric and lower abdominal symptoms from 45 to 33% at 1 wk and to 28% at 2 wk, and from 57 to 40% at 2 wk, respectively. In subjects with gastric symptoms at baseline, the average gastric symptom score per subject significantly decreased by 0.9 at 1 wk and 1.2 at 2 wk. In trial 2 (27 subjects), ingestion of the active preparation significantly decreased the average gastric symptoms score per subject by 1.0 at 1 wk and 1.1 at 2 wk, but ingestion of placebo milk had no effect. No side effects were reported by any subjects in either trial. We conclude that fermented milk containing B. bifidum YIT 10347 has the potential to provide health benefits by alleviating gastric symptoms in subjects taking no medication.

Monozygotic Twins with Discordant Sex

A nine-year-old girl with short stature was referred to the department of pediatrics at Kyushu University. The clinical diagnosis was Turner syndrome; karyotypic analysis performed on peripheral blood, using GTG techniques, demonstrated a 45,X/47,XYY (17:83) mosaicism. Her twin brother, a phenotypically normal male, had the same karyotype; 45,X/47,XYY (3:97) on peripheral blood. Their skin fibroblast karyotypes showed the same mosaicism, ie. 45,X/47,XYY (41:59 and 31:69 respectively). On eleven biochemical genetic markers the twin pair were concordant, thus the likelihood of monozygosity was 0.99527034. In addition, the analysis of variable number of tandem repeat (VNTR) markers revealed the likelihood of monozygosity to be 0.99944386. The most plausible explanation of the X/XYY mosaicism was nondisjunction of the Y in the first cleavage division of the 46,XY zygote. A disproportionate rate of cell populations with 45,X and 47.XYY in the twinning process of the X/XYY embryo, especially in the germ lines, would result in discordant sex in twin pairs.

Characteristics of a granular electronic system in Heusler-type Fe2+xV1-xAl

We report comprehensive measurements of the magnetic, transport, and thermal properties of the Heusler-type compound Fe2+xV1-xAl, with x values near the ferromagnetic quantum critical point, xc ∼ 0.05. At T ∼ 60 K, a prominent Schottky-like anomaly appeared in the specific heat; this anomaly was correlated with a smaller pseudo-gap formation in magnetic susceptibility, magnetoresistance, and thermoelectric power. Furthermore, a magnetic anomaly observed in the magnetic susceptibility and resistivity at T ∼ 4 K was suppressed significantly by applying a magnetic field. A magnetically inhomogeneous phase arose below T ∼ 60 K, which appeared to consist of ferromagnetic and paramagnetic clusters.

Effect of Bifidobacterium bifidum BF-1 on gastric protection and mucin production in an acute gastric injury rat model

Homeostasis in the stomach environment is maintained by the balance of protective factors such as gastric mucus and aggressive factors such as gastric acid, stress, alcohol, and drugs. An overload of aggressive factors that upsets this balance can induce gastric injury. Fermented milk that contains Bifidobacterium bifidum BF-1 (BF-1), a probiotic strain, and Streptococcus thermophilus YIT 2021 (ST) is known to improve Helicobacter pylori-associated gastritis in humans. Here, we investigated the gastroprotective potential of BF-1 in a rat model of acid-ethanol-induced acute gastric injury to fully elucidate its potential compared with ST. Living BF-1, ST, or vehicle was orally administrated to rats, and acid-ethanol gastric injury was induced 2h later. The gastric injury rate was determined and shown to be significantly lower in the BF-1 group than in the vehicle group, which showed a similar level to the ST group. The production of gastric mucin and the expression of several target genes associated with protection and inflammation were examined before and after induction of gastric injury. Interestingly, mucin 5ac (muc5ac) gene expression in gastric corpus samples and gastric mucin production in stomach samples from the BF-1 group, but not the ST group, were significantly higher than those in the respective samples from the vehicle group. These findings indicate that BF-1 has the potential to provide gastroprotection, alleviating acute gastric injury by enhancing the production of gastric mucin in a rat model.

Beneficial effect of oral administration of Lactobacillus casei strain Shirota on insulin resistance in diet-induced obesity mice

AIMS

This study aimed at determining whether oral administration of a probiotic strain, Lactobacillus casei strain Shirota (LcS), can improve insulin resistance, which is the underlying cause of obesity-associated metabolic abnormalities, in diet-induced obesity (DIO) mice.

METHODS AND RESULTS

DIO mice were fed a high-fat diet without or with 0·05% LcS for 4 weeks and then subjected to an insulin tolerance test (ITT) or oral glucose tolerance test (OGTT). Oral administration of LcS not only accelerated the reduction in plasma glucose levels during the ITT, but also reduced the elevation of plasma glucose levels during the OGTT. In addition, plasma levels of lipopolysaccharide-binding protein (LBP), which is a marker of endotoxaemia, were augmented in the murine models of obese DIO, ob/ob, db/db and KK-A(y) and compared to those of lean mice. LcS treatment suppressed the elevation of plasma LBP levels in DIO mice, but did not affect intra-abdominal fat weight.

CONCLUSIONS

LcS improves insulin resistance and glucose intolerance in DIO mice. The reduction in endotoxaemia, but not intra-abdominal fat, may contribute to the beneficial effects of LcS.

SIGNIFICANCE AND IMPACT OF THE STUDY

This study suggests that LcS has the potential to prevent obesity-associated metabolic abnormalities by improving insulin resistance.

Effect of Bifidobacterium bifidum fermented milk on Helicobacter pylori and serum pepsinogen levels in humans

Helicobacter pylori infection is an important risk factor for gastric diseases. Some probiotics are useful for suppressing H. pylori infection. Bifidobacterium bifidum YIT 4007 can improve the experimental gastric injury in rats and the disease stages on the gastric mucosa in peptic ulcer patients. We evaluated the fermented milk using a clone (BF-1) having the stronger ability to survive in the product than this parent strain to clarify the in vitro suppressive effect of BF-1 on H. pylori and the in vivo efficacy of BF-1 fermented milk on H. pylori and gastric health. In the mixed culture assay of BF-1 and H. pylori, the number of pathogens was decreased such that it was not detected after 48 h in the Brucella broth with a decrease in pH values. In the cell culture experiment with human gastric cells, the H. pylori infection-induced IL-8 secretion was suppressed by the preincubation of BF-1. In a human study of 12-wk ingestion (BF-1 group, n = 40; placebo group, n = 39) with a randomized double-blind placebo-control design, the H. pylori urease activity and gastric situation were evaluated using a urea breath test (UBT) and the serum pepsinogen (PG) levels as biomarkers for inflammation or atrophy, respectively. In the H. pylori-positive subjects, the difference (DeltaUBT) of the UBT value from the baseline value in the BF-1 group (n = 34) was lower than that in the placebo group (n = 35) at 8 wk. The baseline UBT values showed a negative correlation with DeltaUBT values at 8 and 12 wk in the BF-1 group but not in the placebo. In the PG-positive subjects classified by the PG test method, the BF-1 group was lower in DeltaUBT values than the placebo group at 8 and 12 wk. In the active gastritis class by PG levels, the BF-1 group was lower in their DeltaUBT values than the placebo at 8 and 12 wk. The PG I levels in the BF-1 group were lower than the placebo at 12 wk. The PG II levels in the BF-1 group did not change during the ingestion period, but the placebo was increased. The PG I/II ratios slightly decreased from baseline at 12 and 20 wk in the BF-1 and placebo groups. These patterns were also observed in the H. pylori-positive subjects. The improving rates of upper gastrointestinal symptomatic subjects and total symptom numbers in the BF-1 group were higher than those in the placebo. These results indicate that BF-1 fermented milk may affect H. pylori infection or its activity, gastric mucosal situation, and the emergence of upper gastrointestinal symptoms.

A double three-step theory of brain metastasis in mice: the role of the pia mater and matrix metalloproteinases

The brain is frequently affected by the spread of lung cancer, and haematogenous metastasis is a common route to brain metastasis. We therefore developed an isogenic brain metastasis model of lung cancer to use the Lewis lung carcinoma cell line and analysed dynamics of neoplastic cells after extravasation. Histological analysis revealed two characteristic patterns: metastatic foci exhibiting an angiocentric pattern were designated 'perivascular proliferations'; neoplastic cells infiltrating the brain parenchyma were designated 'invasive proliferations'. Electron microscopic observation of perivascular proliferations showed that neoplastic cells were confined to the perivascular space. In invasive proliferations, however, fragments of collagen fibre were observed in the gaps between neoplastic cells, indicating that the neoplastic cells had disintegrated the pia-glial membrane. We analysed the expressions of matrix metalloproteinase-2 (MMP-2) and MMP-9 by using both immunohistochemical analysis and real-time polymerase chain reaction analysis. MMP-2 expression was significantly higher in invasive proliferations. MMP-9 expression was significantly higher in day 7, but there was no significant difference in day 11. The pia-glial membrane and perivascular space are the barriers that neoplastic cells must overcome to infiltrate the brain. In conclusion, our findings suggest that brain metastasis requires two distinct processes.

Fluorescence studies on binding of pyrene and its derivatives to humic acid

Binding of pyrene (PyH) and its derivatives to humic acid (HA) has been studied by fluorescence spectroscopy. The nature of the interaction between HA and pyrene derivatives are extensively investigated by employing three derivatives ranging from anionic to cationic compounds: 1-pyrenebutylic acid (PyA), 1-pyrenemethanol (PyM), and 1-pyrenebutyltrimethylammonium bromide (PyB). Binding constants between HA and PyX (X=H, A, M, B) are obtained by steady-state fluorescence quenching techniques, and it is found that PyB has a markedly large binding constant among the pyrene family. This is attributed to a strong electrostatic interaction between cationic PyB and anionic HA. The result suggests that an electrostatic interaction plays a dominant role in binding of pyrenes to humic acid. The importance of electrostatic interaction was also confirmed by a salt effect on the binding constant. Influence of collisional quenching on the binding constant, which causes overestimation of the binding constant, was examined by time-resolved fluorescence spectroscopy as well as temperature effect in steady-state fluorescence measurements. It is elucidated that collisional quenching does not much bring overestimation into the binding constants.

Characterization of Jumping translocation breakpoint (JTB) gene product isolated as a TGF-beta1-inducible clone involved in regulation of mitochondrial function, cell growth and cell death

Jumping translocation breakpoint (JTB) is a gene located on human chromosome 1 at q21 that suffers an unbalanced translocation in various types of cancers, and potentially encodes a transmembrane protein of unknown function. The results of cancer profiling indicated that its expression was suppressed in many cancers from different organs, implying a role in the neoplastic transformation of cells. Recently, we isolated JTB as a TGF-beta1-inducible clone by differential screening. In this study, we characterized its product and biological functions. We found that it was processed at the N-terminus and located mostly in mitochondria. When expressed in cells, JTB-induced clustering of mitochondria around the nuclear periphery and swelling of each mitochondrion. In those mitochondria, membrane potential, as monitored with a JC-1 probe, was significantly reduced. Coinciding with these changes in mitochondria, JTB retarded the growth of the cells and conferred resistance to TGF-beta1-induced apoptosis. These activities were dependent on the N-terminal processing and induced by wild-type JTB but not by a mutant resistant to cleavage. These findings raised the possibility that aberration of JTB in structure or expression induced neoplastic changes in cells through dysfunction of mitochondria leading to deregulated cell growth and/or death.

Intake of purple sweet potato beverage affects on serum hepatic biomarker levels of healthy adult men with borderline hepatitis

OBJECTIVE

To examine the effect of purple sweet potato (PSP) beverage rich in acylated anthocyanins on serum hepatic biomarkers in healthy Japanese men.

DESIGN

A randomized, double-blind, placebo-controlled, parallel study.

SETTING

Kumamoto in Japan.

SUBJECTS

Healthy adult men (30-60 years) with borderline hepatitis who had one or more of serum gamma-glutamyl transferase (GGT), aspertate aminotransferase (AST) and alanine aminotransferase (ALT) levels over normal ranges, and who were negative for hepatitis virus were openly recruited by an advertisement. Of the 48 persons enrolled, 38 (mean age 43.0 years (30-54 years)) completed the study.

METHODS

The subjects were randomly assigned to the PSP group and the placebo group. During the 8-week intervention, the subjects in the PSP group consumed two bottles of the PSP beverage with acylated anthocyanins (200.3 mg anthocyanins per 125 ml per bottle) per day, and the subjects in the placebo group, two bottles of a placebo beverage (1.7 mg anthocyanins per 125 ml per bottle). All of the data measured were analyzed by two-way repeated measures analysis of variance (ANOVA) with groups and times. The data of the hepatic markers were analyzed using the Dunnett multiple comparison among the time points and t-test between groups at the same time point. Two-sided P<0.05 were defined as the level of significance.

RESULTS

Serum GGT, AST and ALT levels showed interactions (P<0.05) between the beverage groups and time; the others were not affected. The PSP beverage group showed lower hepatic marker levels than the placebo group during the ingestion period, particularly the GGT level (-14.1 IU/l, 95% Confidence intervel (CI) -25.4 to -2.7, P=0.017 at 2 weeks; -16.8 IU/l, 95% CI -36.2 to 2.5, P=0.081 at 4 weeks; -26.7 IU/l, 95% CI -47.6 to -5.7, P=0.014 at 6 weeks and -27.9 IU/l, 95% CI -49.9 to -5.9; P=0.014 at 8 weeks). No correlation between alcohol consumption and each hepatic biomarker level before and after the ingestion was observed.

CONCLUSION

The intake of the PSP beverage significantly decreased the serum levels of hepatic biomarkers, particularly the GGT level, in healthy men with borderline hepatitis.

Efficient engraftment of primary adult T-cell leukemia cells in newborn NOD/SCID/β2-microglobulinnull mice

Adult T-cell leukemia (ATL) develops via multiple oncogenic steps in human T-cell leukemia virus type I (HTLV-I) carriers. To better understand pathogenesis of ATL, we developed a novel xenogeneic engraftment model in which primary ATL cells are intravenously transplanted into neonatal nonobese diabetic (NOD)/severe-combined immunodeficiency (SCID)/beta2-microglobulin(null) (NOD/SCID/beta2m(null)) mice. Acute-type ATL cells engrafted in the peripheral blood and in the lymph nodes of recipients at a high efficiency. Engrafted ATL cells were dually positive for human CD4 and CD25, and displayed patterns of HTLV-I integration identical to those of donors by Southern blot analysis. These cells infiltrated into recipients' liver, and formed nodular lesions, recapitulating the clinical feature of each patient. In contrast, in smoldering-type ATL cases, multiple clones of ATL cells engrafted efficiently in NOD/SCID/beta2m(null) mice. When smoldering-type ATL cells were retransplanted into secondary NOD/SCID/beta2m(null) recipients, single HTLV-I-infected clones became predominant, suggesting that clones with dominant proliferative activity can be competitively selected in this xenogeneic system. Taken together, the NOD/SCID/beta2m(null) newborn system is useful to understand kinetics, metastasis, and disease progression of ATL in vivo.

Expression of cholesteryl ester transfer protein (CETP) in germinal centre B cells and their neoplastic counterparts

AIMS

Cholesteryl ester transfer protein (CETP) is known to facilitate the transfer of lipids between plasma lipoproteins. Previous studies on human tissues have determined that the spleen contains large amounts of CETP mRNA, while the exact location of CETP in such organs remains unknown. In the present study, our aim was to locate CETP protein expression at the cellular level in human normal and neoplastic lymphoid organs.

METHODS AND RESULTS

In-situ hybridization (ISH) and immunohistochemistry were applied to pathology specimens. A specific rabbit anti-CETP antibody was used for immunohistochemical analysis, together with another CETP-specific monoclonal antibody. A riboprobe for ISH was derived from CETP cDNA. Immunohistochemically, CETP was localized in germinal centre B cells and a proportion of marginal zone B cells. ISH showed that CETP mRNA was located mostly in the same areas. When 141 malignant lymphomas of various subtypes were studied, high expression of CETP, equivalent to that found in normal germinal centre B cells, was demonstrated in lymphoma subtypes that are currently regarded as the neoplastic counterparts of primarily germinal centre B cells.

CONCLUSION

CETP localizes B cells in germinal centres, a proportion of post-germinal centre B cells and their neoplastic counterparts.

Composition and conservation of the telomeric complex

The telomere is composed of telomeric DNA and telomere-associated proteins. Recently, many telomere-associated proteins have been identified, and various telomere functions have been uncovered. In budding yeast, scRap1 binds directly to telomeric DNA, and other telomere regulators (Sir proteins and Rif proteins) are recruited to the telomeres by interacting with scRap1. Cdc13 binds to the most distal end of the chromosome and recruits telomerase to the telomeres. In fission yeast and humans, TTAGGG repeat binding factor (TRF) family proteins bind directly to telomeric DNA, and Rap1 proteins and other telomere regulators are recruited to the telomeres by interacting with the TRF family proteins. Both organisms have Pot1 proteins at the most distal end of the telomere instead of a budding-yeast Cdc13-like protein. Therefore, fission yeast and humans have in part common telomeric compositions that differ from that of budding yeast, a result that suggests budding yeast has lost some telomere components during the course of evolution.

Inhibition of human telomerase by nucleotide analogues bearing a hydrophobic group

Telomerase, which synthesizes telomeric DNA in eukaryotic cells, is classified as a reverse transcriptase. To clarify the susceptibility of telomerase to nucleoside 5'-triphosphates bearing a hydrophobic group on the base moiety, we studied the inhibitory effects of 2',3'-dideoxy-5-styryluridine 5'-triphosphate analogues and 9-(beta-D-arabinofuranosyl)-2-(p-n-butylanilino)purine 5'-triphosphate analogues on telomerase activity using a quantitative 'stretch PCR' assay. 2',3'-Dideoxy-5-styryluridine 5'-triphosphate (StddUTP) showed more potent inhibition than 2',3'-dideoxythymidine 5'-triphosphate (ddTTP). On the other hand, 9-(beta-D-arabinofuranosyl)-2-(p-n-butylphenyl)guanine 5'-triphosphate (BuParaGTP) showed no inhibition, even though 9-(beta-D-arabinofuranosyl)guanine 5'-triphosphate (araGTP) is a potent inhibitor of telomerase. The influence on telomerase of hydrophobic substituents on the base moieties of nucleotides is described.

Telomerase-inhibitory effects of the triphosphate derivatives of some biologically active nucleosides

Telomerase is a ribonucleoprotein reverse transcriptase that uses its internal RNA moiety as a template for synthesis of telomere repeats. To clarify the susceptibility of telomerase to HIV-1 reverse transcriptase inhibitors (RT), we investigated the inhibitory effects of 3'-azido-3'-deoxythymidine 5'-triphosphate (AZTTP), which is known to be a potent HIV-1 RT inhibitor, and acyclovir triphosphate (ACVTP). Lineweaver-Burk plot analyses showed that the inhibition mode of these compounds was competitive with the substrate dNTP counterpart. However, inhibition by AZTTP was weak (Ki = 15 microM, Km of dTTP = 7.1 microM). Interestingly, ACVTP showed considerable inhibition. The Ki value of ACVTP was 5.0 microM, being smaller than the Km of dGTP (12 microM).

Human cord blood long-term engrafting cells are CD34+ CD38-

There have been controversies about CD34 and CD38 expression by human cord blood (CB) stem cells. Using the newborn NOD/SCID/beta2-microglobulin-null mouse assay that we recently developed, we examined the in vivo engrafting capability of human CB cells. Almost all of the 4-5 months engrafting cells were found in CD34(+) population. The capability of secondary reconstitution was found only in the CD34(+) cells. When the CD34(+) CB cells were separated into CD38(-) and CD38(+) subpopulations and tested for engraftment, the majority of the engrafting cells were detected in the CD38(-) subpopulation. These findings are consistent with the results from studies of murine stem cells and strongly indicate that the phenotype of human CB stem cells is CD34(+) CD38(-).

Evaluation of Bifidobacterium breve strain Yakult-fermented soymilk as a probiotic food

We evaluated the effects of Bifidobacterium breve-fermented soymilk on probiotic function. An administered strain of B. breve strain Yakult was capable of growing in soymilk with no additives as high as 10(9) CFU/ml. During storage of the fermented soymilk at 10 degrees C for 20 days, viable counts of the strain did not change. The growth inhibition of the strain in a bile-containing medium was lessened by the addition of soy protein. In human feeding experiments, the administered B. breve was recovered at a level of over 10(9) CFU/g faeces, accompanied by an increase in the total number of bifidobacteria. These results indicate that fermented soymilk with B. breve strain Yakult could be a novel type of probiotic food.

Soymilk products affect ethanol absorption and metabolism in rats during acute and chronic ethanol intake

In this study we evaluated the effects of soy products on ethanol metabolism during periods of acute and chronic consumption in rats. Gastric ethanol content and blood ethanol and acetaldehyde concentrations were investigated after the oral administration of ethanol (34 mmol/kg) plus soy products such as soymilk (SM) or fermented soymilk (FSM). The gastric ethanol concentration of the FSM group was greater than that of the control group, whereas portal and aortal blood ethanol concentrations of the FSM group were lower than in controls. The aortal acetaldehyde concentration in the FSM group was lower than that of the control group. The direct effect of isoflavones on liver function was investigated by using hepatocytes isolated from untreated rats. Genistein (5 micromol/L) decreased ethanol (P = 0.045) and tended to decrease acetaldehyde (P = 0.10) concentrations in the culture filtrate. Some variables of ethanol metabolism in the liver were investigated after chronic ethanol exposure for 25 d. Rats consumed a 5% ethanol fluid plus the SM diet, the FSM diet or a control diet. Microsomal ethanol oxidizing activity was significantly lower in the FSM group than the control group. Furthermore, cytosolic glutathione S-transferase activity was higher in the SM and FSM groups than in the control group. Acetaldehyde dehydrogenase activity (low K(m)) in the FSM group (P = 0.15), but not in the SM group (P = 0.31), tended to be greater than in the control group. The amount of thiobarbituric acid reacting substances in the liver of the SM and FSM groups tended to be less than that of the control group (P = 0.18 and 0.10, respectively). These results demonstrate that soymilk products inhibit ethanol absorption and enhance ethanol metabolism in rats.

Hypocholesterolemic effect of indigestible fraction of Chlorella regularis in cholesterol-fed rats

The effects of Chlorella regularis powder (CP) and Chlorella regularis indigestible fraction (CIF) on serum and liver lipid concentrations and on fecal steroid excretion were estimated in rats fed diets containing 5 g/kg cholesterol and 2.5 g/kg sodium cholate. The ingestion of 12.7% CP or 5.3% CIF did not influence food intake or growth. CP and CIF decreased the levels of serum cholesterol, but had no effect on the levels of serum triacylglycerol and phospholipid. Liver cholesterol contents were lower in the CP and CIF groups than in the control group, but CP and CIF did not affect liver triacylglycerol content. CP and CIF increased the total amount of fecal neutral steroids excreted, but did not modify the total bile acid excretion. However, the soluble bile acid concentrations of reconstituted fecal water in the rats fed CP and CIF diets were lower than the control value. Moreover, CP and CIF had a high bile acid binding capacity in vitro. These results indicated that CIF had a hypocholesterolemic effect and enhanced fecal neutral steroid excretion while decreasing the soluble fecal bile acid concentration.

Identification and analyses of the Xenopus TERT gene that encodes the catalytic subunit of telomerase

The Xenopus telomerase catalytic component gene, xTERT (Xenopus telomerase reverse transcriptase), has been cloned. The production of xTERT recombinant protein together with the proposed Xenopus telomerase RNA (xTR) (Chen et al., 2000. Cell 100, 503-514) in a rabbit reticulocyte lysate system led to the reconstitution of active telomerase, indicating that both products are functional telomerase components. Both xTERT expression and telomerase activity are high from the early to the late blastula stage. However, they are decreased at the gastrula stage and thereafter, suggesting that the xTERT expression level is the primary mechanism for regulating telomerase activity in Xenopus development. This is the first report of a non-mammalian vertebrate TERT gene. Sequence comparison of xTERT with human and mouse TERTs has uncovered four regions conserved in the amino-terminal halves of vertebrate TERT proteins, the functions of which will be discussed herein.

spRap1 and spRif1, recruited to telomeres by Taz1, are essential for telomere function in fission yeast

Telomeres are essential for genome integrity. scRap1 (S. cerevisiae Rap1) directly binds to telomeric DNA and regulates telomere length and telomere position effect (TPE) by recruiting two different groups of proteins to its RCT (Rap1 C-terminal) domain. The first group, Rif1 and Rif2, regulates telomere length. The second group, Sir3 and Sir4, is involved in heterochromatin formation. On the other hand, human TRF1 and TRF2, as well as their fission yeast homolog, Taz1, directly bind to telomeric DNA and negatively regulate telomere length. Taz1 also plays important roles in TPE and meiosis. Human Rap1, the ortholog of scRap1, negatively regulates telomere length and appears to be recruited to telomeres by interacting with TRF2. Here, we describe two novel fission yeast proteins, spRap1 (S. pombe Rap1) and spRif1 (S. pombe Rif1), which are orthologous to scRap1 and scRif1, respectively. spRap1 and spRif1 are independently recruited to telomeres by interacting with Taz1. The rap1 mutant is severely defective in telomere length control, TPE, and telomere clustering toward the spindle pole body (SPB) at the premeiotic horsetail stage, indicating that spRap1 has critical roles in these telomere functions. The rif1 mutant also shows some defects in telomere length control and meiosis. Our results indicate that Taz1 provides binding sites for telomere regulators, spRap1 and spRif1, which perform the essential telomere functions. This study establishes the similarity of telomere organization in fission yeast and humans.